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Item Open Access Selected underutilized fruits of Northeast India for overall health improvement of humankind(University of North Bengal, 2023) Banerjee, Swarnendu; Sen, ArnabThe North-Eastern hill region in India is a significant agro-biodiversity hotspot with underutilized ethnomedicinal fruits essential for rural life. However, these fruits are often unknown due to lack of documentation, shrinking forest areas, and disappearance of indigenous culture. Plantderived products, particularly fruits, offer numerous benefits and are a promising alternative to current health -promoting medications due to their less expensive and less harmful side effects. Hence, the present study was conducted to collect wild edible fruits with ethnomedicinal values from India's North-Eastern hill region, considering their ethnomedicinal importance. Since these fruits are ethnomedicinal and nutritionally essential, this present investigation aims to explore bioactive phytocompounds from underutilized fruits and their health-beneficial role against some diseases. Fourteen fruit samples were collected from different locations in three states (West Bengal, Meghalaya, and Tripura) among them four fruits: Elaeagnus pyriformis (EP), Baccurea ramiflora (BR), Phyllanthus acidus (PA), and Prunus nepalensis (PN) were selected for further experiments while the remaining fruits were not considered based on DPPH assay. These four fruit extracts [EP (80.91±0.264%), BR (78.864±0.11%), PA (78.053±0.78%), PN (81.56±0.57%) at 200 μg/ml] exhibited higher free radical scavenging activity than the others when compared to the respective standard (ascorbic acid). With increasing concentrations of extracts (50-200 μg/ml), these fruit samples showed promising reactive oxygen species (ROS) scavenging power in the case of other in vitro assays [hydroxyl radical, hydrogen peroxide, nitric oxide, and hypochlorous and total antioxidant assay]. The study showed a strong positive correlation between antioxidant scavenging assay and total phenol and flavonoid content for all four fruit extracts, where EP showed the highest phenol (73.74631 ± 1.171 mg GAE/g DW) and flavonoid content (39.3726±0.6661 mg QE/g DW). High phenol and flavonoid content have been proved by FTIR analysis where EP, BR, PA, and PN extracts indicated the presence of significant peaks for polyphenolic OH, alkane, carboxylic acid, and amide-I at around (3419- 3439 cm-1), (2920-2927 cm-1), (1732- 1740 cm-1) and (1625-1648 cm-1) respectively. The present study was extended to analyze the identification of active phytocompounds in EP, BR, PA, and PN extracts using the GC-MS method. A total number of 38 phytocompounds have been identified in EP (11 compounds), BR (8 compounds), PA (8 compounds) and PN (11 compounds). It has been reported that fatty acids like octadecanoic acid (stearic acid), dodecanoic acid (lauric acid), and hexadecanoic acid (palmitic acid) were present in the fruit extracts that humans need in their diets. Apart from these, ellagic acid, Ƴ-sitosterol, 1,2- Longidione, n-hexadecanoic acid, and octadecanoic acid, 4H-Pyran-4-one, 2,3-dihydro-3,5 -dihydroxy-6-methyl each have anticancer, antidiabetic, nephroprotective, hypocholesterolemic, antibacterial, and antiinflammatory properties. Therefore, based on the study above, it is possible to indicate that EP, BR, PA, and PN extracts can potentially become powerful antioxidative agents in the future. Further LC-MS analysis allowed the identification of more than 75 polyphenols, including flavanols, flavonoids, anthocyanidins, alkaloids, steroids, vitamins, triterpenoids, phenylpropanoids, phenolic acids, and derivatives from four fruit samples (EP, BR, PA, PN). It has been reported that vitamin B9 has antioxidant and neuroprotective properties among these bio compounds and reduces the chances of lipid peroxidation. Reports suggested that flavonoids (trifolin, quercetin-3β-D-glucoside, kaempferol), flavonols (rutin), anthocyanidins (malvidin), phenolic acids (quinic acid, gallic acid, phenolic acid), phenylpropanoids (rosmerinic acid) are potent antioxidant and ROS scavengers. These have high antioxidant, anticancer, anti-inflammatory, hypolipidemic, and immunomodulatory properties. Fruit extracts were investigated against two Gram-positive (Bacillus subtilis, Staphylococcus aureus) and two Gram-negative (Escherichia coli, Salmonella typhimurium) pathogenic bacterial strains to see antimicrobial activity. Among all fruit extracts, PA showed perfect growth inhibitory activity against gram-positive and gram-negative bacteria at low doses (5mg/ml). At high doses (10mg/ml), EP, BR, PA, and PN (all four fruit extracts) showed a significant zone of inhibition against S. typhi (11.576 mm), E coli (14.256 mm), B. subtilis (13.964 mm), S. aureus (15.382 mm) respectively. The study demonstrated that active phytocompounds (beta-sitosterol, octadecanoic acid, γ-sitosterol, and squalene from fruits like EP, BR, PA, and PN, respectively) have potential growth inhibitory activities against pathogenic strains, which suggests these fruits could be used as herbal remedies for microorganism-related disorders. When the ACHN human renal adenocarcinoma cell line was exposed to varying doses of four fruit extracts (EP, BR, PA, and PN), after 48 hours of treatment, the MTT test results offered an interesting concentrationdependent decrease in cell viability, which ranges between 45% to 49% at the highest dose (300 μg/ml) of four (EP, BR, PA, and PN) fruit extracts. This MTT assay data was also supv ported by in silico molecular docking analysis where selected phytocompounds (Malvidin, Rosmerinic acid, Ellagic acid Quercetin for EP, BR, PA, and PN respectively) showed potential inhibitory activities against the MDM2 protein, which is a positive regulator for adenocarcinoma. Probably, this was the first report on the cytotoxic effects of these underutilized fruit extracts on the ACHN cell line. An increasing dose ((5, 10, 20, 40 mg/ L) of resveratrol (a potent polyphenol from EP) demonstrated protection against H2O2-induced oxidative injury and increased sperm viability by upregulating several frontline antioxidant and non-antioxidant enzymes such as SOD (165-172%), GSH (18.5- 91.43%) respectively, reducing ROS level [NOX (39-55%)] improving altered lipid metabolism and histological architectures (Sertoli cells and seminiferous tubules regenerates). In silico molecular docking study also supports this data where resveratrol showed good inhibitory potential (- 7.8kcal/mol) against stress protein NOX2. The different resveratrol treatments had better antioxidant activities than the standard antioxidant, ascorbic acid (AA). Therefore, this phyto compound might be a promising medicine against stress-mediated male infertility problems. Fruit wines (fermented alcoholic beverages) are traditionally popular in the cool climatic zones of Northeast India. A study on fruit wines in Northeast India found high antioxidant activity, medicinal potential, and significant anti-cancer activity in breast cancer cell-line studies. Metagenomic analysis revealed diverse probiotic bacterial species in the wine sample's microbial population, playing an essential role in anti-cancer properties. Overall, the study suggests wine has therapeutic and health benefits. The study also describes the green synthresis of silver nanoparticles (AgNPs) from silver nitrate utilizing EP fruit juice in an optimized process, which caused the solution's color to shift from yellow to brownish. UVVis spectroscopy, SEM, FESEM, EDX, XRD, and FTIR were used to characterize the AgNPs thoroughly to determine the existence and degree of bioactive compounds as a capping and reducing agent. Additionally, the antibacterial activity of AgNPs against human pathogenic microorganisms was shown to be substantial, and their antioxidant effectiveness was assessed. The anti-apoptotic protein Bcl- XL was employed in an in-silico molecular docking investigation to determine the efficacy of AgNPs as a powerful anti-cancerous agent. According to the results, nanoparticles are deemed harmless as they can alter how cancer cells typically initiate cell death by blocking their ABC transporters. A similar study was done using BR fruit juice, and surface morphology, size, and stability of biogenically synthesized AgNPs were determined by SEM, FESEM, HRTEM, EDX, XRD, and DLS. In this study, DPPH and other in vitro antioxidant assays explored the effect of these nanoparticles in treating oxidative stressrelated disorders. The antimicrobial assay revealed that AgNPs have potent antibacterial activity against both above mentioned gram-positive and gram-negative bacteria. Two human breast cancer cell lines were used in an MTT test to determine the anticancer effects. Results indicated that AgNPs were cytotoxic to the cell lines in a dose-dependent manner, with IC50 values of 110 mg/ml and 140 mg/ml, respectively, after 48 hours of treatment. We may conclude from this work that AgNPs are highly effective in preventing cancer. The study synthesized nanoparticles from Phyllanthus acidus fruit juice to investigate its clinical effects. The study compared the efficacy of raw fruit juice and nanoparticles on gentamicin-induced nephrotoxicity in a mouse model. The present study administered gentamicin (negative control) intraperitoneally to induce nephrotoxicity in the mice model. Several in vivo antioxidant and biochemical tests were performed to measure the efficacy of low and high doses of fruit juice and juicesynthesized nanoparticles in preventing renal injury. Results revealed that creatinine and urea levels significantly deteriorated by up to 1.13% and 1.49% in the high-dose P. acidus nanoparticles (PANH) group compared to the negative control group. After the application of PANH, major antioxidant (SOD, CAT) and nonantioxidant (GSH) enzymes were significantly enhanced compared to the gentamicin-treated group. Histopathological examination revealed that the glomerulus structure reappeared significantly in the PANH group. In silico molecular docking, analysis showed an inhibitory effect of fruit juice and fruit juice synthesized nanoparticles against inflammatory protein NFƙb. Findings indicated that PANH was more ameliorative over a high dose of P. acidus fruit juice (PAJH) towards kidney injury. Our findings generate scopes to explore the therapeutic potentials of PANH in treating kidney disorders. Now a days arsenic, a toxic metalloid, poses a significant threat to human health and agriculture. In India, the highly nutritious Vigna mungo (L.) Hepper (Blackgram) pulse crop, Urad, is highly contaminated, leading to failure in germination and reduced crop yield. This contamination is particularly prevalent in West Bengal, Murshidabad, and Malda districts, where blackgram is cultivated alongside other cash crops. The build-up of arsenic in grains endangers agricultural productivity and food security because arsenic stress inhibits seed germination and plant growth. To reduce Asphytotoxicity in plants and seedlings before they reach the reproductive stage, this study investigated the viaviii bility of seed-priming black gram plants with biogenic zinc oxide nanoparticles (ZnONPs). ZnONPs under stress considerably increased the germination rate of blackgram seeds (20– 23.33%) and other morphophysiological characteristics. Adding ZnONPs reduced the accumulation of malondialdehyde (21–69%) and reactive oxygen species (ROS) (hydrogen peroxide) by 23–67%. ZnONPs also led to an increase in the activity of antioxidant enzymes (superoxide dismutase by 28–68%, catalase by 20– 42%, guaiacol peroxidase by 19–49%, and ascorbate peroxidase by 26–39%) and the accumulation of osmoregulators. The findings suggest that ZnONPs significantly reduce Astoxicity by preventing its transfer from the root to the shoot. This work provides the first proof that ZnONP-based nano-priming effectively reduces Asstress in blackgram, indicating the possible application of this technique as a stress-relieving agent in Ascontaminated regions to boost yield and growth. Another important legume in the food chain such as peas (Pisum sativum L.) are rich in nutrients. However, arsenic (As) in the agroecosystem provides a considerable bottleneck to its productivity because of its severe effects on ontogeny, particularly in Southeast Asia. This work proposes biogenic ZnONPs as a rhizospheric nanoremediation technique to avoid Asgenotoxicity and increase crop production. In the negative control, germination rate, shoot length, and root length dropped by 62%, 16%, and 14.9%, respectively, above the normal control. As-toxicity caused fast oxidative bursts with worsening morphophysiological properties. Negative control experienced membrane damage (82.75% increase) and electrolyte leakage (2.6-fold increase) as a result of ROS buildup (12.8 and 9-fold increase in leaves and roots), overworked antioxidant defense, and loss ix of cellular homeostasis. According to the study, root tip cells under stress significantly increase nuclear area, nuclear fragmentation, and micronuclei formation. These findings suggest severe genomic instability and increased programmed cell death (with a 3.3-fold increase in early apoptotic cells) due to leaky plasma membranes and unrepaired DNA damage. ZnONPs adsorb into the rhizosphere and reduce As-toxicity, they improve the antioxidant response and reduce As-uptake in peas. As-interference is reduced by increased vacuolar sequestration of As due to improved phytochelatin fabrication. Better photosynthetic activity (1.3–1.9-fold increased chlorophyll autofluorescence), increased pollen viability, and less genotoxicity (reduced tail DNA in comet assay) were observed. The flowering time was also better (7.74– 19.36% reduction in flowering delay) with greater transcript abundance of GIGANTIA (GI), CONSTANS (CO), and FLOWERING LOCUS T (FT) genes. Pod number and seed zinc concentration increased up to a maximum of 37.5% (1.67-fold), whereas seed arsenic content was reduced when treated with ZnONPs. In our experiment, the maximum ZnONPs dose (400 mg/L) caused NP-toxicity in pea plants; however, up to 300 mg/L, the best stress alleviation was seen. Although blackgram and pea are highly significant pulse crops, the use of nanoparticles in reducing heavy metals or metalloid stress in these crops has never been reported. Through this investigation, we hope to fully assess the viability of using ZnONPs to reduce stress caused by As. Therefore the detailed study on underutilized fruits have shown their potentiality against several diseases like cancer, infertility, nephrotoxicity and improves human health in a drastic way.Item Open Access Evaluation of silica nanoparticles and their functionalization in the alleviation of salinity stress in two legumes -Lens Culinaris and Glycine Max(University of North Bengal, 2023) Sarkar, Mahima Misti; Roy, SwarnenduSoil salinity is one of the major environmental stresses that imparts drastic effects on plant growth and development. The adverse effects of salinity affect the overall plant health, resulting in impaired physiological and biochemical attributes. Poor health ultimately causes a loss in plant production rate and nutritional values. To overcome the negative effects of salinity and to improve the yield of crop plants, major emphasis has been given to the application of several fertilizers, pesticides, and fungicides. Moreover, the development of genetically modified crops has been advocated for the development of salt-tolerant crop plants. However, these have some drawbacks, such as genetic modification being timeconsuming and cost-consuming and applying chemical fertilizers hampering soil fertility. Moreover, the efficiency of fertilizers, considered important for improving crop yield, reduces soil fertility due to over-application, resulting in residual toxicity on crop plants. In this context, in the last decade, nanotechnology has emerged as an alternative strategy for the betterment of plant health as well as environmental stress alleviation. The idea behind using nanoparticles in crop improvement was to improve the efficiency of the bulk materials already used as agrochemicals. Because of having a high surface area to volume ratio, the nanomaterials facilitate easy uptake and render them more interactive with the cellular active components, thereby amplifying their efficiency. Though silica is not an essential element in plants, its deficiency creates various problems; thus, it is considered a semi-essential element. The application of silica nanoparticles (SiNPs) has excellent potential for crop improvement because it increases silica availability to plants. The synthesis of any nanoparticles demands an optimization process through which we can understand the ratios of components that should be used to get the actual shape, size, and surface charge. In this purview, the second chapter presents the synthesis, optimization, and characterization of SiNPs. SiNPs were optimized by varying the three important ingredients (TEOS, ethanol, and ammonia) through ‘Design Expert 13’ based ‘mixture design’, which revealed that the size of the SiNPs can be modified but not the surface charge. Using mixture design, we successfully obtained ~50 nm-sized SiNPs, which was confirmed through several analytical techniques. To study the potential of SiNPs in salinity stress alleviation, four concentrations of NaCl (for seedling and vegetative stage – 0, 100, 200, and 300 mM; for reproductive stage – 0, 200, 400, and 600 mM) in combination with four concentrations of SiNPs (0, 1, 5, and 10 g/L) were applied in two legume crops – lentil, and soybean, respectively (Chapters 3 and 4). The results depicted that both plants had better germination attributes under salinity after the application of SiNPs. In the seedling and vegetative stages, SiNPs were found to improve the plant’s health under salinity through improved plant height, relative water content, photosynthetic pigments, ionic and osmotic balance, antioxidant defense (enzymatic and/ non-enzymatic), membrane stability and reduced ROS accumulation. Similarly, in the reproductive stage of both legumes, applying SiNPs was also observed to reduce the salinity stress impacts through improved plant health, yield, and nutritional aspects of the seeds. The use of bare SiNPs has already been proven to have beneficial attributes for crop plants under salinity. However, very little research has focused on applying functionalized nanoparticles for crop improvement under environmental stresses. Surface functionalization of these nanoparticles with bioactive molecules has the potential to increase their efficiency in this regard. Thus, in chapters 5 and 6, the SiNPs surface was functionalized with two important sugars/osmolytes – glucose (GSiNPs) and trehalose (TSiNPs), respectively. Both surface functionalizations were confirmed using several analytical techniques, including FTIR, XRD, DLS with zeta potential, UV-visible spectroscopy, SEM, EDS, TEM, and AFM. Applying both GSiNPs and TSiNPs improved the health of lentil and soybean seedlings through improved height, photosynthetic pigments, ion balance, and antioxidant defense under salinity stress. In both plants, the improvement was found to be more profound with the use of GSiNPs and TSiNPs compared to the bare SiNPs. The bioassay experiments also proved that the functionalization of the SiNPs surface with glucose/trehalose increased the bioavailability and uptake of both silica and sugars in the seedlings. Thus, these studies can provide ample evidence of the greater efficacy of surface-functionalized nanoparticles in palliating salinity stress in plants. Apart from the morphological, physiological, and biochemical analyses, we performed the molecular and genetic background of the beneficial effects of surface functionalized SiNPs (TSiNPs) by performing the whole transcriptome analysis (RNA-Seq). The results revealed that the TSiNPs have regulatory roles on various genetic expression, which modulates various protein expressions, pathway functions, cellular components, molecular functions, and biological processes to confer progressive health benefits for lentil seedlings under salinity. More specifically, some of the genes involved in the providence of salinity stress tolerance (Sodium hydrogen exchanger, Potassium transporter, Cytochrome b6, sugar transporter, and ABC transporter G family member) were expressed highly in the presence of TSiNPs. Along with their beneficial effects on crop improvement, various nanoparticles have also been found to have toxic effects on plants, animals, and environmental elements. So before proceeding to the filed application and commercialization, the SiNPs must also be checked for their toxicity attributes. In this purview, the cytotoxicity and genotoxicity of the synthesized SiNPs were evaluated on the Allium cepa root tip, considering their applied concentration and size. Further, the toxicity effects of SiNPs were attempted for attenuation using surface functionalization with sugar molecules – GSiNPs and TSiNPs. The results showed that the SiNPs showed toxic effects after the 100 g/L concentration, and the 30 nm and 100 nm sized SiNPs showed more toxic effects than the 50 nm-sized nanoparticles. Further, the GSiNPs and TSiNPs were found to reduce the toxicity level of SiNPs even at higher concentrations (> 100 g/L). A toxicity study was also performed on soil microflora, and the results showed that the SiNPs, GSiNPs, and TSiNPs improved the soil microbial communities (mixed soil bacteria, phosphate solubilizers, nitrogen fixers, and silica solubilizers) in control (0 mM NaCl) as well as 300 mM NaCl stress conditions. Finally, the SiNPs, GSiNPs and TSiNPs were developed into nanoformulations (slowrelease type) using sodium alginate as internalizing polymers. The results of Chapter 9 revealed that the alginate internalization makes the silica and/or sugar release from SiNPs, GSiNPs, and TSiNPs at a slower rate, considering the effect of incubation time, pH, and temperature. These nanoformulations also improved the seedling growth even better than the bare and functionalized SiNPs, even in the presence of NaCl stress. However, the cost of production at the laboratory scale is relatively high, and our future emphasis is to make these nanoformulations cheaper so that they can handed over to the farmers for field application.Item Open Access Dwitiya biswajuddho samokalin o poroborti bangla natoke bashosthaner sonkot o samadhan : ekti porjalochona (1940-1980) দ্বিতীয় বিশ্বযুদ্ধ সমকালীন ও পরবর্তী বাংলা নাটকে বাসস্থানের সংকট ও সমাধান : একটি পর্যালোচনা (১৯৪০-১৯৮০)(University of North Bengal, 2023) Shannigrohi ষন্নিগ্রহী, Mallika মল্লিকা; Roy রায়, Ashit অসিতItem Open Access Thermophilic lignocellulose deconstructing microbial consortium: Mining of Cellulolytic glycoside hydrolases for saccharification of agro residues(University of North Bengal, 2023) Lepcha, Khusboo; Ghosh, ShilpiPlant cell wall lignocellulose is recognized as one of the most abundant source of fennentable sugars with potential use in the production of different value added products like biofuel and other chemicals. Deconstruction of the complex lignocellulose into useable monomers by microbial enzymes has been long adapted; however a major bottleneck in efficient bioconversion of cellwall polysaccharide by enzymes is that plant cell walls have evolved to resist enzymatic deconstruction - a factor collectively known as "biomass recalcitrance". Using a broader suite of enzymes for hydrolysis of cellulose and hemicelluloses to fennentable sugars would be a better approach to combat biomass recalcitrance. Ln nature also, lignocellulosic biomass is degraded with the cooperation of many microorganisms producing a variety of cellulolytic and hemicellulolytic enzymes under aerobic and anaerobic conditions. The biodegradation of cellulosic biomass through the use of microbial co-cultures or complex communities has been proposed as a highly efficient approach for biotechnological application, since it avoids the problems of feedback regulation and metabolite repression posed by isolated single strains. In this study microbial communities of lignocellulosic habitat of forest soil (FS) and goat rumen contents (GR) were adapted to grow and survive at higher temperatures in destarched wheat bran /rice straw as sole carbon source to generate four thennophilic microbial consortia amongst which the consortium developed from goat rumen contents bred on rice straw (GR~ RS) was selected for further analysis due to its better hydrolytic potential on the basis of enzyme assays and in-gel analysis. Characterisation of cellulolytic and xylanolytic potential of GR-RS revealed both the cellulolytic and xylanolytic potential to be thennophilic and thermostable over a broad range of pH. The enzymes were tolerant to and activated in the presence of many metal ions such as Magnesium, Calcium, Barium, Sodium etc. whereas it was greatly reduced to 10% by Hg2+. Comparative Taxonomic profiling of GR-RS-T (developed at 60°C) and GR-RS-M (developed at 37°C) by meta.genomic analysis revealed GR-RS-M had a majority of Proteobacteria (48.67%), Finnicutes (30.34%), Verrucomicrobia (5.45%), Bacteroidetes (5. 12%), Planctomyecetes (3.13%), wheras GR-RS-T exhibited majority of bacteria belonging to phyla Proteobacteria (34.65%), Bacteroidetes (31 %) and Finnicutes (30.83%). Analysis of differential transcriptional expression of cellulolytic and xylanolytic enzymes in GR-RR-T revealed that expression of cellulases and xylanases were mostly from Paenibacillus , Thermobacillus, Pseudoclostridium, Geobacillus, Clostridium etc in case of GR-RS-T whereas its expression were mostly from Klebsiella, Cellulomonas and Pseudoxanthomonas in case of GR-RS-M. The analysis of transcriptome for distribution of different classes of CAZymes revealed that GR-RS-T had GH (34%), GT (38%), CBM (17%), AA (I%), CE (9%) and PL (1 %) whereas GR-RS-M had GH (29%), GT (43%), CBM (16%), AA (3%), CE (8%) and PL (I%). It was also revealed that most families of GH, PL and AA had higher abundance in GRRS- M as compared to GR-RS-T based on the number of reads detected. The study highlights the significance of sub-culturing the lignocellulolytic population from goat rumen contents at 60°C which selects and maintains the therrnophiJic members for production of thermophilic GHs as also evidenced by in vitro analysis. Comparison of saccharification potential of Conso,tiurn Enzyme Preparation (CEP) from GR-RS-T with commercial cellulase blend (CCB) on biologically pretreated rice straw (Spent rice straw) revealed a much higher release by CCB as compared to CEP indicating the supreme potential of the former which has been designed and developed for commercial applications. SEM image of SRS control showed prominent holes and cracks on its surface as compared to the intact strucrure of URS control indicating the delignification of rice straw and loosening of its structure during the growth of P!eurotus sp on rice straw. The structure of URS and SRS after saccharification showed prominently higher level of disorganisation when CCB was used as compared to CEP which cotTelated with the release of reducing sugars from the substrates. The release of reducing sugars in case of SRS-CEP ( 175 mg/gm) was comparable to, in fact slightly higher than URS-CCB (158 mg/gm) indicating that the saccharification potential of CEP could be made comparable to CCB if biologically pretreated rice straw was used. The outcome of this research contributes to the growing interest in lignocellulose deconstruction by enzymes, and highlights the potential of biological pretreatment in enhancing sacbharification by GHs.Item Open Access Photophysical and sensorial behaviour of different chromophoric systems comprising electron donor-acceptor units(University of North Bengal, 2023) Rahman, Ziaur; Das, Sudhir KumarResearch on developing new electron donor–acceptor (EDA) based molecular systems, which benefit from extended π-conjugation, is a rapidly growing research area. That has resulted in several technological applications, including fluorescent dyes, laser dyes, brightening agents, metal sensors, pH sensors, bio-imaging, organic photovoltaics (OPVs), organic light-emitting diodes (OLEDs), and many more. The photophysical properties of donor (D)-acceptor (A) based molecular systems depend on the substitution pattern and the D-A unit's nature, making them prime derivatives for application in organic photonics. The most frequent method for tuning the photophysical properties of organic compounds is to connect an electron-rich “D” and an electron-deficient “A” group directly or indirectly. The π-linkage between the “D” and “A” units results in a D-π-A type of conjugated molecular system, where the photophysical/electronic properties of D-π-A systems can be tuned by either (i) changing the “D” or “A” unit strength or (ii) varying the π-linker between the “D” and “A” units. A wide range of D-A conjugated systems with varying “D” and “A” units have been developed for various applications in chemistry, physics, materials science, and biology. Because of their superior photophysical characteristics, these are used to develop and create various sensory materials for monitoring biological events and detecting various target analytes. Chemosensors based on photoluminescence are essential among the many approaches and methodologies because they have multiple benefits, such as on-site detection, real-time monitoring with rapid response, innately high sensitivity, and simplicity of handling compared to other techniques. Considering the real benefit of the chromo-fluorogenic EDA system, present thesis explores its practical benefit for detection of various target analytes. A brief summary of each chapter of the present thesis are given below one by one. Chapter 1: This chapter begins with a brief discussion of the EDA system-based chemosensors and then moves to the general principle and working mechanism for designing chemosensors based on different photophysical processes with examples. This chapter deals with the objectives and applications of the present work in the present context of scientific development. Chapter 2: This chapter explores the reversible acidochromic behavior of a benzoxazole-based scaffold (BPP), which is highly sensitive to the acid-base in the liquid and gas phases. With the addition of acid, the solution of BPP changes its color from yellow to pink fuchsia due to the transformation of its imine into quinonoid form. The color change is completely reversible in the presence of the base, confirming the reversible acidochromic behavior of the present BPP system. Further, a paper strips-based test kit has been demonstrated for the practical utility of the present acidochromic BPP to identify a trace amount of acid-base in solution and gas-phase, respectively. The mechanistic aspects of detecting acid-base and colorimetric change in the presence of acid-base have been explored by density functional theoretical investigations and 1H NMR experiments. Moreover, we have constructed a reconfigurable dual-output combinatorial INH/IMP logic gate. Chapter 3: This chapter highlights the investigation of anion interactions and recognition abilities of naphthalene derivative, [(E)-1-(((4-nitrophenyl) imino) methyl) naphthalen-2-ol], (NIMO) by UV–visible spectroscopically and colorimetrically. NIMO shows selective recognition of F− ions colorimetrically, and the naked eye observes a visual color change from yellow to pink. The F− ions recognition is fully reversible in the presence of HSO4− ions. The limit of F− ions detection by NIMO could be possible down to 0.033 ppm-level. A paper strips-based test kit has been demonstrated to detect F− ions selectively by the naked eye, and a smartphone-based method for accurate sample analysis in the non-aqueous medium has also been demonstrated. The pKa value calculation and DFT analysis support spectroscopic behavior to find a correlation with receptor analyte interaction. The optical response of NIMO towards the accumulation of F− ions and, subsequently, HSO4− ions as chemical inputs provide an opportunity to construct INH and IMP molecular logic gates. Chapter 4: In this chapter, a fluorosensor derived from 4-aminophthalimide, ((E)-5-((2-hydroxy benzylidene) amino) isoindoline-1, 3-dione, HID working with excited state intramolecular proton transfer (ESIPT) mechanism is synthesized and employed for the selective recognition of aluminum (Al3+) ions and picric acid (PA) based on 'off-on-off' fluorescence mechanism. The sensor HID shows a turn-on fluorescence response towards Al3+ ions in H2O/DMSO (9:1, V/V) with a rapid response time (2 minutes) and exceptional sensitivity (LOD = 0.77 μM). The binding constant (K) of HID with Al3+ ions is estimated to be 1.32 × 108 M-2. The 1:2 stoichiometries of the complex between HID and Al3+ ions are confirmed through Job's plot and 1H NMR spectral analysis. Al3+ chelated HID complex is further employed to detect explosive nitroaromatic compounds, especially PA. Furthermore, using these two chemically encoded inputs, and corresponding optical output, we constructed the INH molecular logic gate with Al3+ and PA. The HID chemosensor and Al3+ chelated HID complex are also applied to map Al3+ ions and PA in the living cell. The HID chemosensor and Al3+ chelated HID complex's performance toward detecting Al3+ ions, and PA demonstrates that it might be used as a signaling tool for analyzing biological and environmental samples. Chapter 5: This chapter attempts to introduced a photoluminescence ionic liquid and its application for detecting nitro explosives. Due to the rising menace of illicit actions and pollution aroused by explosive nitroaromatic compounds (NACs), the growth of an adept sensor for detecting these NACs is essential. Herein, in this communication, a photoluminescent IL-assimilated group of uniform materials based on organic salt (GUMBOS) and Nano-GUMBOS has been fabricated by integrating pyrene butyrate with a quaternary phosphonium IL (PbIL) via a simple ion exchange process. Neat PbIL shows a bright cyan color photoluminescence under a 365 nm UV lamp irradiation and is employed as photoluminescence security ink and picric acid (PA) detection among the tested NACs. By simple reprecipitation method, we have developed water-suspended crystalline pyrene assimilated nanoparticles, nPbIL, characterized by various analytical techniques. The PbIL-derived water-suspended nanomaterials, nPbIL, display a robust cyan color excimer-like emission, which turns blue (monomeric) due to adding PA over the other related NACs. This ratiometric cyan-to-blue photoluminescence change is due to the displacement of the anionic pyrene moiety of the nPbIL by the picrate anion. The fabricated organo nanosensor is enormously discerning and responsive towards PA with a LOD of 0.77 nM and is superior to many available in the literature. Additionally, a fluorogenic paper strip-based test kit experiment has been demonstrated to detect and quantify PA selectively in aqueous solvents amongst the other tested NACs. The present contribution evokes a novel approach to developing different IL-based chemosensors for detecting and quantifying various target analytes. Chapter 6: This chapter attempts to demonstrate the role of different mimics of G-series nerve agents and their detection method. There is a pressing need for rapid and accurate recognition of hazardous G-series nerve agents in the solution and vapor phases to protect individuals from undesirable wars and terrorist attacks. However, achieving this goal in practice presents significant challenges. This contribution introduces a specific and selective acridine-based fluorogenic sensor, AMA, which exhibits turn-on behavior from cyan to blue photoluminescence under the exposure of a 365 nm UV lamp in response to diethylchlorophosphate (DCP), a mimic of sarin gas, in both liquid and vapor phases, respectively. The mechanism underlying the identification of DCP using AMA has been elucidated through 1H-NMR titration investigation and HRMS analaysis. The fluorgenic, DCP-specific AMA shows an outstanding selectivity, excellent sensitivity, and a broad linear span of 15-38 μM, with an identification limit of 7.9 nM, which is found to be superb than many chemosensors available in the literature without any interference. To facilitate its potential practical applications, we have introduced an AMA-coated test kit utilizing Whatman-41 filter paper, which can be used as a handy and visual photonic device for on-spot identification of DCP as a mimic for sarin gas under the colonial crowding condition of other analogous analytes. Furthermore, we have demonstrated a fluorogenic dip-stick method to detect and quantify the DCP vapor under the exposure of a 365 nm UV lamp. Chapter VII: Finally, a brief summary of the present thesis and the future perspective from the present research work has been delineated in this chapter.Item Open Access Role and status of sherpa and tamang women in forest villages of Darjeeling hills : a comperative study(University of North Bengal, 2023) Lama, Dipika; Bhui, UjjwalTribals are the original inhabitants of the forest and are known by different names such as Vanyajati (forest communities) and Vanavasi (inhabitants of forests). Tribals depend on the forests for food, fuelwood, timber, material for crafts, fodder, and medicinal plants, and it is often the tribal women who collect these resources. They are also known as the “Sentinels or Custodians” of forest and its natural resources. Since time immemorial these people living in the forests have developed a cordial relationship with the forest and have vast knowledge about different plant species and other forest products used for different purposes. Women are the worst victims of environmental degradation as they are solely dependent on natural resources for their livelihood. Women all over the world share a special relationship with the environment and tend to be more concerned about the availability and access to natural resources. The knowledge that the tribal women possess is generally transmitted from generation to generation and it plays an important role in the conservation and uses of forest resources. This in turn helps in alleviating the problems at the local level and it will not further lead to the conflicting situation. Various researches all over the world show that both environmental and ecological security risks affect women more than the men. The traditional concept of security focuses on the protection of state from external military threats but now it is replaced by concepts such as economic security, food security, health security, environmental security, energy security, cyber security and human security. At present non-traditional security concepts are challenges to the survival and well being of people all over the world. The present study tries to show how the tribal women residing in the forest villages of the Eastern Himalayas play a significant role in protecting the forest environment as their livelihood revolves around it. On the other hand, these women play an important role in the family and society and help contribute to the overall development of society. With this background, the present study tries to investigate the role and status of Sherpa and Tamang women residing in the forest villages of Darjeeling Hills with the help of various indicators on socio-economic factors, historical background and the Sherpa and Tamang women's relationship with the forest and the various roles played by them in the conservation of the environment. The present study is conducted in the forest villages situated in the three subdivisions of Darjeeling Hills namely Darjeeling, Kurseong, and Kalimpong (presently Kalimpong subdivision is converted into a district). Darjeeling Hills is located in the northernmost part of West Bengal comprising both plains and the hills. Fifteen forest villages have been selected from Darjeeling subdivision, Kurseong subdivision and Kalimpong subdivision. From each subdivision five forest villages have been selected. Tribal communities such as Sherpas, Tamangs, Lepchas, and Bhutias are found in the study area. However, the tribal communities such as Sherpas and Tamangs are in maximum number and are found in a majority of the forest villages. So, women respondents from the Sherpa and Tamang communities have been selected for the present study. For the selection of the respondents stratified random sampling techniques have been used from the area under study. A total of 300 respondents have been selected. 150 each from Sherpa and Tamang women have been selected since it is based on the comparative study. From each subdivision, 100 respondents were interviewed and from each forest village, 20 respondents were selected. Primary and secondary techniques have been used for the collection of data. Primary data have been collected through intensive field surveys, face-to-face interaction, and observation, with the help of a semi-structured open-ended interview schedule. Whereas, secondary data is mostly collected from books, journals, newspapers, internet sources, census reports, and government reports provided by the panchayat office and the forest department. Different parameters were taken into consideration to understand the role and status of the Sherpa and Tamang women in the forest villages of Darjeeling Hills. The forest villages' geographical isolation makes them more vulnerable to initiating better economic activities for the villagers. Selected forest villages are located in different geographical settings. The majority of the forest villages are located in the hilly areas and other forest villages are located in the foothills. Since agriculture is the main occupation of the respondents, they grow different types of vegetables according to their geographical conditions. The entire agricultural operations such as seed selection, weeding, sowing, watering, and storing are performed by the women. Other economic activities include livestock rearing, daily wage workers, and other miscellaneous activities. At present, Sherpas residing in the forest villages are trying new avenues i.e. homestays and are making good profit out of it. They economically contribute to their families’ well-being which automatically enhances their status in the family and society. The role played by Sherpa and Tamang women for their family and society is commendable and their decision is crucial for the overall development of the society. Apart from these, their role in the protection of the environment is significant as they are very much concerned about the forest environment and are devoted to combating environmental degradation. Various governmental and nongovernmental agencies provided various facilities to these respondents which helped them in uplifting their status. The present study is divided into seven chapters and makes a modest attempt to study the Sherpa and Tamang communities in detail. The findings of the study will surely provide insight into the Sherpa and Tamang women who have been residing in the forest villages of Darjeeling Hills. Therefore, this study aims to delve into a deeper understanding of these tribal women residing in the Eastern Himalayas.Item Open Access Violation, resistance and repression : a study of crime, public disorder and control in colonial North Bengal (1864-1947)(University of North Bengal, 2023) Barman, Tushar Kanti; Bhattacharya, Dahlia; Khasnobish, Sudip'The concept or crime. criminality and public disorder and its control during colonial rule is one of the most debated issues chat added a new dimension to the arena of social histor~,. Crime is a social phenomenon and the simple definition or crime is that it is an action punishable by criminal law. No behavior or action can be ,iudged as crime without the legal provision or punishment. But it is di mcult to understand what the historical definition of crime in colonial India was. as the rulers who codified the criminality of Indians to all kinds of prejudices· against the people whom they ruled. Hence. the legal inspection of crime and criminality in colonial lndia was effectively a colonial construction. Similarly. the term ·public disorder' resulting from group actions. violating legal norms which are closely related to the concept of crime as traditionally understood. Therefore, public disorder is a situation in which public order is violated or threatened. Hereafter. widespread violent clashes between n,vo or more groups. such as communal riots. peasant's agitation. labour unrest. political violenc;c etc. would pose grave threats to public order. In the colonial discourse every widespread violent activity were treated as public disorder but for the Indians it ww, a survival or protest against the colonial oppressor. I lowcver, since the days of British inception. Northern Bengal had shown diverse forms of crime ranging from dacoity or gang robbery Lo (')ett_ offences. In North Bengal number of notorious gang dacoites has been found who were involved in land as well as river dacoities accompanied by murders. In fact. it was an unavoidable and direct outcome of the Company's terrible fiscal policy along with money-lenders who frequently charged exorbitant rates or interest. Hereafter, some of them had ,ioined in crime by accident. !'iOmc for poverty and some for rncre curiosity and some people also joined to help the poor and needy. On the contrary, couple of references and o11icial accounts show that, the crirninals of this region usually came from the lower ordel' of the society and they have been involved in various forms of crime. Dacoity wa~ hereditary. and the nolorious gang concealed themselves among the heterogeneous class. Among them a group of tribes like Choto B!,agrya M11chi, llh11r, Pa/war Dusadh, Pasi. ( 'hai11 ,\tlallah Sandars and Mallahs were considered by the British authority as 'dangerous' community and they came under the Criminal Tribes /\ct. They were involved in dacoities. burglaries. thefls and river crimes mainly. It was impossible for the police to trace them out. Most or the suspect. could easily escape away to adjacent dense forest and neighboring State. Similarly. crime related to property. skirmishes due to civil dispute. forgery, will ful murder out of suspicion remained high during this period in North Bt:ngal. This system victimized even women. There have been lots of instances wh<.!re women were abused. abducted and harassed in many ways. The civil disputes relating to crops and personal vendetta led Lo affray. Murder also rose due to personal disputes and fraud. Murder or the children and prostitutes for the sake of ornaments was also a widespread crime in some districts of North Bengal. In regards to the public order problem. 1he major issues of public disorder which rocked Northern part of Bengal were agrarian unrest, tea garden workers agitation. tailway workers unrest etc. which the historians have called survival or protest crimes. A class of educated intellectual citizens came forward against this British exploitation and oppression of the regime that was able to spread the form of British exploitation lO the masses in every canopy. Among the public order issues most important were the Rangpur Rebell ion, Indigo Revolt, Chatrishu movement. tea garden workers unrest e1c. Furthermore, affray and riots. rai lway industrial workers unrest was a particular type of violent collective ··offences'·, attended with or without loss of I ite, against person or persons. widespread in the countryside in the phase of colonial rule. It was usually an open shadow of violence between two armed parties over a variety of rural disputes. Although the colonial government did nor attach much irnportance to such criminal activity in the early stages. they gradually became alarmed as the level of crime increased. Because 1·he main target of the criminals was the English merchants. indigo factories. or the Zamindrrs, .lotedars and moneylenders who were loyal to the British government. So, all this crime and criminals threatened the colonial administration. To curb the crime and to establish peace in the second half of the nineteenth century the colonial government took various administrative measures in the districts of North Bengal. The British government was determined to put down offl!nces against property. individuul life and ensure public safety to create a politic.al and administrative environment conducive to trade and investment and to maximize revenue extraction. Therefore. it became an objective necessity from the colonial viewpoint Lo codify the law. create a colonial police force as a legitimate instrument of coercion. reform of the court of justice from tor to bottom and renovale the rudimentary prison network that enabled the devices of control to prevent crime and to force the law and order in this portion of the country. 1 Ience, imprisonment and development of prisons as a penal institution under the British Raj were a significant addition in the criminal justice system of colonial North 81.:ngal as well as India. Thus. the history of crime. public disorder and its control in colon.ial North Bengal clearly emerges as a significant area of study. I Ience, the objet:Live of Lhe study is divided into some crucial themes. Firstly, viewing crime as an ingredient of social history, the study dealt with the evolution of crime and criminals from the backdrop of socio-economic and regional diversity anu the nature of colonial policies and exploitations. Similarly, lhe study intends to seek the rapiJ devdopmenL of tea and railway industry and modernization of economy and the relationship between crime and industrialization and crime and scarcity. Secondly. the study also intends to bring out certain unexplored facts of the major issues of public order problems which rocked No1thern part of Bengal as a form of colonial discourse i.e. • Public Disorder'. The study tries to analyze their causes in brief and main focus lies with the violent activities of the common people and how the colonial authorities approach to tackle such disorders and the responses of the colonial administration and its changing perceptions regarding crime and public order issues. Thirdly. the study is to provide an analysis of historical trends of the various institutions that has been used by colonial Government in the forms of control mechanism like police. Court. Jai I etc .. and how through this method of control their surveillance gesture was being fulfilled.Item Open Access Emerging dimensions of cash management in industry with special reference to the industrial units located in North Bengal(University of North Bengal, 2023) Prasad, Pawan; Roy, DipenCash management is of paramount importance for the systematic running of all operational activities and the survival of a business firm. The study was undertaken to examine how the industrial units in North Bengal are undertaking this important task to ensure the survival and growth of their businesses. Given the weak industrial infrastructure and culture, the industrial units have the compulsion to apply prudent methods of cash management. This paper examined the convergence and divergence of receipts and payments. Pointing to the great divergence, the study recommends synchronization of receipts with payments without creating pressure on the finances of the company. The study used panel data analysis to explore the motives behind cash holdings. The findings from data analysis show that precautionary motives play the dominant role behind excessive cash holdings. Besides, the precautionary motive, the transaction motive is also playing a significant role in determining the cash holdings of the firms. The study also reflected that the percentage of cash holdings of the sample firms is, more or less, similar to Indian manufacturing firms. The introduction of electronic payment systems, the adoption of information technology, and innovations in the banking system are emerging dimensions that greatly influence cash management. Handling of physical currency and maintaining cash in hand are gradually reducing. The data revealed that doing transactions using physical currency has now reduced to ten per cent of total transactions. It means that soon cash management will be routed via bank accounts, which is likely to make a cashier and Cash Book almost obsolete. The study added recommendations for better synchronization of receipts and payments with the use of cash Budgets so that a payment failure as well as excessive cash holdings can be avoided. It will help to reduce the risk, hence the need for holding cash for precautionary needs.Item Open Access Vulnerability of agriculture and introduction of smart agricultural practices (SAPs): an assessment in Koch Bihar District, West Bengal(University of North Bengal, 2023) Das, Satyajit; Lepcha Nee Lama, IndiraThe agricultural system is crucial for food, nutrition and livelihood security in India and this sector of India occupies almost 43 per cent of India ׳s total geographical area (Arjun, 2013). The economy of Koch Bihar district is also based on agriculture as the cultivators and agricultural labourers constitute the main work force of this district, they share 32.3% and 34.7% of the total workers respectively (District Census Handbook, Koch Bihar, 2011). The area under marginal holdings with size of less than 1 hectare increased from 1, 28,277 hectares (46.69 per cent of total area) in 2000-01 to 1,32,758 hectares (48.46 per cent of total area) in 2005-06. Reciprocating this, area under medium-sized holdings (having average size of 4 hectares to less than 10 hectares) decreased drastically from 8,805 hectares to 2,094 hectares from 2000-01 to 2005-06. (District Statistical Hand Book, Koch Bihar, 2010-11). Inadequate marketing channels and infrastructure, long intermediation, lack of accurate and timely market information system etc. are also the major challenges to the agricultural marketing system in the district (Bhowmik, 2012). The agricultural activity primarily depends on weather and climatic condition and any variation of its pattern create the vulnerability in this sector. The vulnerability of agriculture leads to low level of production, increase input cost, low net profit etc (Sharma, 2021). The vulnerability ranks of Koch Bihar district is 54 among the 161 districts in the Indo-Gangetic Plains (Sehgal et al.2013). The decision-makers need to address the vulnerability of agriculture for different regions is important as the resources are limited and they also should plan various Smart Agricultural Practices (SAPs) based on vulnerability assessment, because the vulnerability of agriculture is possible to minimize by the adaptive capacity (Sehgal et al. 2013). So, there is an urgent need for the adoption of Smart Agricultural Practices (SAPs) to enhance the production and productivity through sustainable use of natural resources, reduce the input cost, increase the net profit, and generate employment. For the solution of the problems related to agricultural vulnerability, a detailed study and research work about vulnerability of agriculture and adoption of Smart Agricultural Practices (SAPs), is very crucial ( Reddy and Dixit, 2017). Keeping in view these problems, the present study entitled ‗Vulnerability of agriculture and introduction of Smart Agricultural Practices (SAPs): An assessment in Koch Bihar District, West Bengal. ‘ Consider six objectives such as (I) To identify the indicators of vulnerability of agriculture in Koch Bihar district. (II) To assess block wise spatial variation in vulnerability of agricultural within the district. (III) To study block wise Smart Agricultural practices (SAPs) and its determinants in Koch Bihar district. (IV) To study block wise farmers' awareness & adoption level of various Smart Agricultural practices (SAPs) in the study area. (V) To study the problems faced by the farmers‗ for adopting Smart Agricultural practices (SAPs) in the district. (VI) To suggest some suggestions for promotion of Smart Agricultural Practices (SAPs) in Koch Bihar district. The present study is based on both primary and secondary data. The primary data has been collected by using purposive and random sampling. A schedule has been prepared for the collection of primary data relating to determinants of Smart Agricultural Practices (SAPs), awareness level about Smart Agricultural practices (SAPs), adoption of Smart Agricultural Practices (SAPs), and to get in depth knowledge about the problems and prospects of Smart Agricultural Practices (SAPs). The sample villages are identified during the pilot survey from the 12 CD blocks in which the Smart Agricultural Practices have been run by the Government assistance or by farmer club. During the survey it was observed that paddy tranplanter, thresher, zero tillage practices in maize, mustard cultivation is very significant in the district and has rarely been practiced. For the collection of primary data related to this research work, two sampling technique have been adopted namely purposive sampling and random sampling without replacement. Use of paddy transplanter and thresher, zero tillage, Integrated Farming System (IFS) is practiced more or less in all the blocks of the district. Purposive sampling technique has been used to obtain the villages which follow Smart Agricultural Practices (SAPs). During the pilot survey 36 villages were identified among the 1132 villages of Koch Bihar district on the basis of zero tillage and various types of SAPs i.e. use of paddy transplanter, use of seed drill, drip and sprinkler irrigation, vermicompost, Integrated Farming System (IFS), use of mulching, bio-flock fishing and paddy cum fishing, crop insurance, Soil Health Card (SHC), Krishnan Credit Card (KCC) etc. Koch Bihar district has 12 Community Development Blocks and 1132 inhabited villages covering an area of 3387 sq.km. Samples have been taken from the selected 36 villages for the assessment of Smart Agricultural Practices (SAPs). To obtain the primary data at the household level random sampling technique without replacement has been used. For determining the sample size of unknown population, Cochran‘s formula (1963) was used. By applying 5% assumed population to the Cochran‘s formula, it gives the value of 73 as number of samples for each block which has been rounded off to 75. Thus 75×12 = 900 samples have been taken from the 36 villages. The number of samples at village level has been selected on the basis of how many villages having followed Smart Agricultural Practices (SAPs) in each block. The secondary data has been collected by reviewing various research articles related to the present work. The essential secondary data for monthly maximum temperature, monthly minimum temperature, mean monthly rainfall; net sown area/geographical area, productivity of food grains, average landholding of farmer, population density, organic carbon (C) content of soil; irrigated area, Human Development Index, cropping intensity, livestock density, villages electrified, villages with paved roads have been used for the present research work. The data has been collected from West Bengal District Statistical Hand Book (2015), Koch Bihar Bureau of Economics & Statistics (Government of West Bengal 2017), District Census Handbook (2011), District Gazetteer (2011), District Agricultural Annual Plan 2021, Krishi Vigyan Kendra (KVK) Koch Bihar, Agriculture Development Offices (ADO) of Koch Bihar district, research articles, reports etc. There are seven chapters in the thesis. The first chapter covers the significance, objective, hypotheses, sampling structure, data sources and methodology of the current study. The physical and socio-economic background of the study area is covered in the second chapter. In this chapter the agro-climatic location, geology, relief, drainage features, soils, and natural vegetation; climatic factors like rainfall and temperature, different extreme events; land holdings, population density, and KCC holder farmer, status of road connectivity at the block level also described. The third chapter deals with the various indicators and spatial variation of agricultural vulnerability in the study area. The fourth chapter depicted the socio-economic status and different types smart agricultural practices in the study area and also identify the different indicators that determine the adoption of smart agricultural practices (SAPs). The fifth chapter discusses the awareness and adoption level of various smart agricultural practices in different block of the study area. The chapter six addresses the main issues relating to the adoption of smart agricultural practices that makes remedial actions to resolve the issues and implement some new policy for the promotion of such smart technique in the study area in future. The chapter seven described the main findings of the research work as well as some suggestion strategies for the policy maker to development of this sector that will be important to the farming community of Koch Bihar district. Koch Bihar district belong to Terai-Tista Alluvial Zone which is fall in Eastern Himalayan Agro climatic region. The climatic condition of this district is humid to peri-humid with average 250–300 mm annual rainfall and the summer and winter temperature is in an around 33°C as the highest in the month of May, while the lowest temperature is 7°C in the month of January(SATSA, Koch Bihar District Unit). Physiographically there are two parts in this district, one is active alluvial plain another is recent alluvial plain and both are formed by Tista river. In orderly the soil of this study area is fall under Entisol and there are 4 soil series are found i.e. Lotafela, Matiarkuthi, Balarampur and Rajpur seriers (SATSA, Koch Bihar District Unit). The elevation of the study area varying between 30-50 meters above mean sea level is essentially a flat region with slight South-Eastern slope along which the main rivers (Tista, Torsa, Kaljani, Gadadhar, Raidhak, etc.) flow. Geographically this district located in the north-Easter part of West Bengal. The latitudinal and longitudinal extensions of the study area are 25°57ʹ57ʹʹN to 26°32ʹ58ʹʹN and 88°45ʹ28ʹʹE to 89°51ʹ50ʹʹE respectively. Total geographical area of this district is 338700 ha (3387 sq.km) of which 1146 ha is net sown area and 246491 ha is gross cropped area. There are 4 agricultural sub-divisions which occupies 12 blocks and 128 Gram Panchayats with 1132 inhabited villages (Census of India, 2011). Politically the northern and eastern part of Koch Bihar district is bounded by Jalpaiguri, Alipurduar district and the Assam state respectively. While the Southern, western, South-Western parts of the district are bounded by Bangladesh. Agricultural vulnerability defined as the latent probability of loss and damage of an agricultural system associated with climatic variability and the occurrence of an extreme climatic event, and the susceptibility of any individual or social group to its impacts. So, the vulnerability of agriculture is function of climatic exposure, sensitivity and adaptive capacity within the system and also the degree to which the agricultural system is susceptible to, or unable to cope with the adverse effects of climatic variability. The term exposure describes how much and how a system is exposed to major climatic variability. Sensitivity is the measure of how much a system is changed or impacted by internal, external, or occasionally both types of disruptions. Adaptive capacity is also defined as the potential or ability of a system, region or community to adjust to the effects or impacts of climate change. In case of exposure the blocks of Haldibari, Mekhliganj, Mathabhanga-I, Mathabhanga-II, Koch Bihar –I, Koch Bihar-II, Sitalkuchi and parts of Sitai, Dinhata-I, Tufanganj-I shows high to very high composite exposure ranging from 0.524 to 0.868. The higher rate of minimum temperature in kharif and rabi seasons and higher intensity of low and high rainfall in kharif season has resulted in extreme exposure in these blocks. Moderate to low exposure are found in south eastern and eastern parts of the district comprising of Tufanganj-II and Dinhata-II blocks with value ranging from 0.008 to 0.523. The reasons for low exposure in the above mentioned blocks are due to lower rate of change in maximum and minimum temperatures in kharif and rabi seasons and very low to moderate rainfall variability. In case of sensitivity the central and western parts of the district namely Mathabhanga-I (0.776), Mathabhanga-II (0.755), Sitalkuchi (0.727), Koch Bihar-I (0.755) are very highly sensitive owing to highest percentage of marginal and small farmer, high population density, low organic carbon content. The remeaning blocks Tufanganj-I(0.674), Tufanganj-II(0.667), Dinhata-I(0.687), Dinhata-II(0.689), Koch Bihar –II(0.645), Mekhliganj(0.617), Haldibari (0.406) and Sitai (0.472) have moderate to low sensitivity owing to average net sown area, productivity and low population density. The adaptive capacity in Koch Bihar-II, Dinhata-I, Dihata-II, Tufanganj-I, Haldibari blocks of the district is very low because of lower percentage of irrigated area and cropping intensity. The adaptive capacity is low in the blocks of Koch Bihar –I and Mathabhanga-II. There is moderate adapative capacity in Sitalkuchi and Tufanganj-II blocks. However Halibari, Mekhliganj, Sitai and Mathabhanga-I blocks shows in higher adaptive capacity comparatively, because More Female work participation in agricultural activity, more Irrigated area, more livestock density and frequently contact with extension services by the farmer. So the overall agricultural vulnerability ( Normalized ) very high in the blocks of Tufanganj-II (0.826), Tufanganj-I (0.833), Koch Bihar- II (0.838), Koch Bihar- I (1.00) due to high exposure and sensitivity and lower adaptive capacity. Agricultural vulnerability is high in the blocks of Dinhata-I (0.702) and Dinhata-II (0.743). Moderate agricultural vulnerability is found in Mekhliganj (0.292) and Sitalkuchi (0.458) block. The agricultural vulnerability is low in Sitai (0.00), Haldibari (0.0) and Mathabhanga –I (0.211). Even through these blocks have high exposure and sensitivity they have higher adaptive capacity. Smart Agriculture Practices (SAPs) are those practices, which increase farmers׳ income and agricultural productivity in a sustainable way that build resilience and capacity of agricultural systems to adapt or mitigate the adverse effects of the climatic variability, and also reduce the greenhouse gases while enhancing national food security. So, Smart Agriculture Practices (SAPs) are the alternative for food and livelihood to cope up with the agricultural vulnerability and helpful in mitigation the adverse effects of climate change and variability. It is clear from the above study that the adoption of Smart Agricultural Practices are strongly determined by the education, land type, land holding mass media exposure and extension contact that was obviously significant in all blocks of Koch Bihar district. Age group of more than 50 years, female gender, and neuclear family type are slightly negativily associated with Smart Agricultural Practices (SAPs) adoption, but there was no significant association because the regression models were insignificant in those cases. Findings clearly revealed the most aware as well as adopted SAPs are use of HYV seed, crop rotation and intercropping, Integrated Farming System (IFS), plant protection measure. On the other hand the least aware and adopted SAPs are soil test and use of Soil Health Card, mulching, zero tillage, Information and Communication technologies (ICTs), e-marketing, polyhouse vegetable and rainwater harvesting, crop insurance, smart animal husbandry. From the overall analysis it can be concluded that the awareness level of each smart agricultural practice is higher than the adoption of that respective practice in every block of this district. From the overall analysis it has been observed that though there are some prospects of Smart Agricultural Practices as it helps to build the agricultural system more resilient to climate change to reduce the production cost and increased yield and give better economic returns to the farmers. But the farmer of the district faces a number of problems in adoption of Smart Agricultural practices (SAPs). The most prominent problem is small and fragmented landholding for adopting integrated farming System (IFS) and different farm power machinery because most of the farmers are marginal and small farmer. The other issues such as scarcity of storage, agro processing unit and cooperative organization at local level, Lack of farm equipments and Inadequate farm inputs, lack of getting proper information and knowledge are also the barrier to adopt smart agricultural practices in the study area. The economy of the Koch Bihar district is basically agrarian type and the agricultural activity being practiced by the farmers is become vulnerable. However, some Smart Agricultural Practices (SAPs) are implemented by the central Government as National Initiative on Climate Resilient Agriculture (NICRA) project to minimize this challenged in this district but the farmers are facing various problems to adopt and utilize these practices properly. So, the present study is mainly concentrated to identify the indicators of agricultural vulnerability, to assess the variation in vulnerability of agricultural and also to identify farmers` awareness and the problems regarding adoption of Smart Agricultural Practices (SAPs) facing by the farmers in every blocks of this district. The present study is unique in this regard and the outcome of the present study surely give some inputs to the planners to implement new programs and project to cope up from the vulnerability in agricultural activity in Koch Bihar district.Item Open Access Metal free C- H Functionalization: a unique tool for library synthesis of functionalized 4- pyrimidiones(University of North Bengal, 2023) Roy, Sanjay; Das, SajalThe Present Thesis entitled as “Metal free C- H Functionalization: a unique tool for library synthesis of functionalized 4-pyrimidiones” has made some efforts to synthesize the diverse 4 pyrimidones with varied functional groups via different approaches and their applications in medicinal and pharmacological domains. Based on different direction and contents of the work; the thesis has been divided into four chapters. Chapter I: describes an introduction to present work, the “A brief review on C-H functionalization/activation and a literature study regarding the synthesis of 4Hpyrido[ 1,2-a]pyrimidin-4-one derivatives” Summarizes a brief review on pyrimidines and it was further subdivided into following points: 1) Origin, background theory, importance and current status of C-H Functionalization. 2) Use of C-H functionalization techniques in selective functionalization of heterocycles. 3) Importance of 4-pyrimidiones and current literature status 4) Different approaches of its synthesis and further derivatization Chapter II: describes “Microwave-assisted straight forward synthesis of 2-substituted alicyclic fused pyrimidone” We have divulged here a metal free- and MW assisted route to tetrahydro-4H-pyrido[1,2- a]pyrimidin-4-one and dihydropyrrolo[1,2-a]pyrimidin-4(6H)-one has been demonstrated by the reaction of aminoacrylates with lactams in presence of phosphorous pentachloride. This transformation comprises of the sequential formation of three new bonds to produce pyrimidone derivatives under mild reaction conditions and this strategy is well compatible for both electron deficient and electron rich amino-acrylates. This method is amenable for gram scale reaction.