Designed novel nuclear localizing anticancer peptide targets p53 negative regulator MDM2 protein.

Intracellular protein-protein interactions provide a major therapeutic target for the development of peptide-based anticancer therapeutic agents. MDM2 is the 491-residue protein encoded by the MDM2 oncogene. Being a ubiquitin-protein ligase, MDM2 represses the transcription ability of the tumor suppressor p53 by proteasome-mediated degradation. Under typical cellular circumstances, a sustained p53 expression level is maintained by negative regulation of MDM2, whereas under stress conditions, this is alleviated to increase the p53 level. Modulation of MDM2-p53 interaction via fabrication of an MDM2-interacting peptide could be a useful strategy to inhibit subsequent proteasomal degradation of p53 and initiation of p53 signaling leading to the initiation of p53-mediated apoptosis of tumor cells. Here, in this research work, a novel anticancer peptide mPNC-NLS targeting the nucleus and the MDM2 protein (p53 negative regulator) was designed to promote the p53 protein activity for the prevention of cancer. It induces effective apoptosis in both A549 and U87 cells and remains non-cytotoxic to normal lung fibroblast cells (WI38). Further, immunocytochemistry and Western blot results confirm that the designed mPNC-NLS peptide induces the apoptotic death of lung cancer cells via activation of p53 and p21 proteins and remarkably stifled the in vitro growth of 3D multicellular spheroids composed of A549 cells.

Design, in silico study, synthesis and evaluation of hybrid pyrazole substituted 1,3,5-triazine derivatives for antimalarial activity.

OBJECTIVES: Malaria is a significant global health challenge, particularly in Africa, Asia, and Latin America, necessitating immediate investigation into innovative and efficacious treatments. This work involves the development of pyrazole substituted 1,3,5-triazine derivatives as antimalarial agent. METHODS: In this study, ten compounds 7(a-j) were synthesized by using nucleophilic substitution reaction, screened for in silico study and their antimalarial activity were evaluated against 3D7 (chloroquine-sensitive) strain of P. falciparum. KEY FINDING: The present work involves the development of hybrid trimethoxy pyrazole 1,3,5-triazine derivatives 7 (a-j). Through in silico analysis, four compounds were identified with favorable binding energy and dock scores. The primary focus of the docking investigations was on the examination of hydrogen bonding and the associated interactions with certain amino acid residues, including Arg A122, Ser A108, Ser A111, Ile A164, Asp A54, and Cys A15. The IC50 values of the four compounds were measured in vitro to assess their antimalarial activity against the chloroquine sensitive 3D7 strain of P. falciparum. The IC50 values varied from 25.02 to 54.82 µg/mL. CONCLUSION: Among the ten derivatives, compound 7J has considerable potential as an antimalarial agent, making it a viable contender for further refinement in the realm of pharmaceutical exploration, with the aim of mitigating the global malaria load.

Substance P-Derived Extracellular-Matrix-Mimicking Peptide Hydrogel as a Cytocompatible Biomaterial Platform.

Self-assembled short peptide-based hydrogel platforms have become widely applicable biomedical therapeutic maneuvers for their soft, tunable architecture, which can influence cellular behavior and morphology to an inordinate extent. In this work, a short supramolecular hydrogelator peptide, substance P, has been designed and synthesized from the C terminus conserved "FFGLM" section of a biologically abundant neuropeptide by using a fusion approach. In addition, to incorporate a good hydrophobic-hydrophilic balance, the truncated pentapeptide segment was further C-terminally modified by the incorporation of an integrin-binding "RGD" motif. Thanks to its N-terminal Fmoc group, this octapeptide ensemble "FFGLMRGD" undergoes rapid self-assembly to give rise to an injectable, pH-responsive, hydrogel-based self-supporting platform that exhibited good cytocompatibility with the cultured mammalian cells under both 2D and 3D culture conditions without exerting any potent cytotoxic effect in a Live/Dead experiment. A rheological experiment demonstrated its hydrogel-like mechanical properties, including thixotropicity. The atomic force microscopy and field emission scanning electron microscopy images of the fabricated hydrogel show a tangled fibrous surface topography owing to the presence of the N-terminal Fmoc-FF residue. Furthermore, an in-vitro scratch assay performed on fibroblast cell lines confirmed the wound-ameliorating potency of this designed hydrogel; this substantiates its future therapeutic prospects.

Design and development of novel N-(4-aminobenzoyl)- l-glutamic acid conjugated 1,3,5-triazine derivatives as Pf-DHFR inhibitor: An in-silico and in-vitro study.

In the present work, a library of 120 compounds was prepared using various aliphatic and aromatic amines. Finally, 10 compounds were selected through in silico screening carrying 4-aminobenzoyl-l-glutamic acid and 1,3,5-triazine moiety. The docking results of compounds 4d16 and 4d38 revealed higher binding interaction with amino acids Asp54 (-537.96 kcal/mol) and Asp54, Phe116 (-618.22 kcal/mol) against wild (1J3I) and quadruple mutant (1J3K) type of Pf-DHFR inhibitors and were comparable to standard WR99210. These compounds were developed by facile and microwave-assisted synthesis via nucleophilic substitution reaction and characterized by different spectroscopic methods. In vitro antimalarial assay results also suggested that these two compounds were having higher antimalarial activity against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strain out of the ten synthesized compounds with IC50 13.25 µM and 14.72 µM, respectively. These hybrid scaffolds might be useful in the lead discovery of a new class of Pf-DHFR inhibitors.

In silico screening, synthesis, and antimalarial evaluation of PABA substituted 1,3,5-triazine derivatives as Pf-DHFR inhibitors.

OBJECTIVES: Drug resistance in malaria parasites necessitates the development of new antimalarial drugs with unique mechanisms of action. In the present research work, the PABA conjugated 1,3,5-triazine derivatives were designed as an antimalarial agent. METHODS: In this present work, a library of two hundred-seven compounds was prepared in twelve different series such as [4A (1-23), 4B(1-22), 4C(1-21), 4D(1-20), 4E(1-19), 4F(1-18), 4G(1-17), 4H(1-16), 4I(1-15), 4J(1-13), 4K(1-12) and 4L(1-11) ] respectively using different primary and secondary aliphatic and aromatic amines. Ten compounds were ultimately selected through in silico screening. They were synthesized by conventional and microwave-assisted methods followed by in vitro antimalarial evaluations performed in chloroquine-sensitive (3D7) and resistant (DD2) strains of P. falciparum. RESULTS: The docking results showed that compound 4C(11) had good binding interaction with Phe116, Met55 (-464.70 kcal/mol) and Phe116, Ser111 (-432.60 kcal/mol) against wild (1J3I) and quadruple mutant (1J3K) type of Pf-DHFR. Furthermore, in vitro, antimalarial activity results indicated that compound 4C(11) showed potent antimalarial activity against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strain of P. falciparum along with IC50 (14.90 µg mL-1) and (8.30 µg mL-1). CONCLUSION: These PABA-substituted 1,3,5-triazine compounds could be exploited to develop a new class of Pf-DHFR inhibitors as a lead candidate.

Invasion potential of the aquarium pet snail Planorbella trivolvis in India: impact of certain abiotic and biotic factors.

Planorbella trivolvis (ramshorn snail) is one of India's most extensively sold exotic aquarium pet snails. The unintentional or deliberate release of P. trivolvis may result in the colonisation and establishment as an invasive snail in freshwater ecosystems. However, the successful invasion of P. trivolvis will depend on several abiotic and biotic factors of the concerned freshwater ecosystem. We have assessed the possibility of overcoming the opposing factors in P. trivolvis invasion through laboratory-based experiments and examined the effects of household-derived pollutants on egg hatchability, adult survivability and fecundity, and temperature (15 to 35 °C) on growth, sexual maturity, and reproduction. Additionally, we have evaluated the potential of native predators as biotic resistance to invasion by prey-choice experiment. The results indicated that egg hatchability, adult survivability, and fecundity were reduced with increasing pollutant concentration. However, the same traits did not differ from a native freshwater snail, Indoplanorbis exustus. The fecundity of P. trivolvis increased with increasing body size, but no considerable differences at different temperature levels suggest a wide range of adaptation to temperature. Faster growth and the requirement of comparatively few days to attain sexual maturity were observed in the higher temperatures. The native predators, Glossiphonia weberi and Diplonychus rusticus, avoided P. trivolvis as prey over the alternative prey snails in most instances, suggesting the masking of biotic resistance against the colonisation. Our observations indicate that the chance dispersal of P. trivolvis from household or commercial aquaria may lead to a possible invasion of freshwater ecosystems under suitable conditions.

Monitoring tea plantations during 1990-2022 using multi-temporal satellite data in Assam (India).

Background: Tea is a valuable economic plant grown extensively in several Asian countries. The accurate mapping of tea plantations is critical for the growth and development of the tea industry. In eastern India, tea plantations have a significant role in its economy. Sonitpur, Jorhat, Sibsagar, Dibrugarh, and Tinsukia are major tea-producing districts in Assam. Due to the rapid increase in tea plantations and the burgeoning population, a detailed mapping and regular monitoring of tea plantations are imperative for understanding land use alteration. Objectives: The present study aims to analyse the dynamics of tea plantations from 1990 to 2022 at a decadal scale, using satellite data, such as Landsat-5 and Sentinel-2. Methods: A supervised classifier called Random Forest (RF) was deployed in the Google Earth Engine (GEE) platform to classify tea plantations. Results: The results showed significant growth in tea plantations in the district of Dibrugarh (112%), whereas the remaining districts had a growth rate of 45-89%. During 32 years (1990-2022), about 1280.47 km2 (78.71%) of areas of tea plantations expanded across five districts of Assam. Precision and recall were used to measure the accuracy of tea plantations classification, which exhibited considerably high F1 scores (0.80 to 0.96). Conclusions: This study helps to demonstrate the application of remote sensing techniques to evaluate the dynamics of tea plantations which can help policymakers to manage the tea estates and underlying changes in land cover.

Pharmacoinformatics-based identification of transmembrane protease serine-2 inhibitors from Morus Alba as SARS-CoV-2 cell entry inhibitors.

Transmembrane protease serine-2 (TMPRSS2) is a cell-surface protein expressed by epithelial cells of specific tissues including those in the aerodigestive tract. It helps the entry of novel coronavirus (n-CoV) or Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in the host cell. Successful inhibition of the TMPRSS2 can be one of the crucial strategies to stop the SARS-CoV-2 infection. In the present study, a set of bioactive molecules from Morus alba Linn. were screened against the TMPRSS2 through two widely used molecular docking engines such as Autodock vina and Glide. Molecules having a higher binding affinity toward the TMPRSS2 compared to Camostat and Ambroxol were considered for in-silico pharmacokinetic analyses. Based on acceptable pharmacokinetic parameters and drug-likeness, finally, five molecules were found to be important for the TMPRSS2 inhibition. A number of bonding interactions in terms of hydrogen bond and hydrophobic interactions were observed between the proposed molecules and ligand-interacting amino acids of the TMPRSS2. The dynamic behavior and stability of best-docked complex between TRMPRSS2 and proposed molecules were assessed through molecular dynamics (MD) simulation. Several parameters from MD simulation have suggested the stability between the protein and ligands. Binding free energy of each molecule calculated through MM-GBSA approach from the MD simulation trajectory suggested strong affection toward the TMPRSS2. Hence, proposed molecules might be crucial chemical components for the TMPRSS2 inhibition.

Implication of in silico studies in the search for novel inhibitors against SARS-CoV-2.

Corona Virus Disease-19 (COVID-19) is a pandemic disease mainly caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It had spread from Wuhan, China, in late 2019 and spread over 222 countries and territories all over the world. Earlier, at the very beginning of COVID-19 infection, there were no approved medicines or vaccines for combating this disease, which adversely affected a lot of individuals worldwide. Although frequent mutation leads to the generation of more deadly variants of SARS-CoV-2, researchers have developed several highly effective vaccines that were approved for emergency use by the World Health Organization (WHO), such as mRNA-1273 by Moderna, BNT162b2 by Pfizer/BioNTech, Ad26.COV2.S by Janssen, AZD1222 by Oxford/AstraZeneca, Covishield by the Serum Institute of India, BBIBP-CorV by Sinopharm, coronaVac by Sinovac, and Covaxin by Bharat Biotech, and the first US Food and Drug Administration-approved antiviral drug Veklury (remdesivir) for the treatment of COVID-19. Several waves of COVID-19 have already occurred worldwide, and good-quality vaccines and medicines should be available for ongoing as well as upcoming waves of the pandemic. Therefore, in silico studies have become an excellent tool for identifying possible ligands that could lead to the development of safer medicines or vaccines. Various phytoconstituents from plants and herbs with antiviral properties are studied further to obtain inhibitors of SARS-CoV-2. In silico screening of various molecular databases like PubChem, ZINC, Asinex Biol-Design Library, and so on has been performed extensively for finding effective ligands against targets. Herein, in silico studies carried out by various researchers are summarized so that one can easily find the best molecule for further in vitro and in vivo studies.

Analytical hierarchy process tool in Google Earth Engine platform: a case study of a tropical landfill site suitability.

Kolkata being a metropolitan city in India has its main municipal solid waste dumpsite situated at Dhapa just adjacent to the East Kolkata Wetlands (Ramsar site). The current prevalent situation at Dhapa is open dumping leading to various contaminations and hazards putting forth the need to look for alternative sites where the landfiilling operation can be shifted to using scientific methods. A user interface (UI)-based analytical hierarchy process (AHP) tool has been developed within the Google Earth Engine (GEE) cloud platform to find out the alternative dumping sites using geospatial layers. AHP function is not available as a native algorithm or developed by any researcher in GEE. The tool has three major functionalities, of which the first one handles the UI elements. The AHP procedure is within another function, and the last function integrates the AHP coefficients to the layers generating the final suitability layer. Users can also upload comparison matrix as GEE asset in the form of CSV file which gets automatically integrated into the AHP to calculate the coefficients and consistency ratio to generate the spatial suitability layers. This approach showcases a generalized AHP function within the GEE environment, which has been done for the first time. The tool is designed in the cloud platform which is dynamic, robust and suitable for use in various AHP-based suitability analysis in environmental monitoring and assessment.

In silico study, synthesis, and evaluation of the antimalarial activity of hybrid dimethoxy pyrazole 1,3,5-triazine derivatives.

Malaria continues to become a major global health problem, particularly in Sub-Saharan Africa, Asia, and Latin America. The widespread emergence of resistance to first-line drugs has further bolstered an urgent need for a new and cost-effective antimalarial(s). Thus, the present study enumerates the synthesis of novel hybrid dimethoxy pyrazole 1,3,5-triazine derivatives 7(a-j) and their in silico results short-listed three compounds with good binding energies and dock scores. Docking analysis shows that hydrogen-bonding predominates and typically involves key residues, such as Asp54, Tyr170, Ile164, and Arg122. The in vitro antimalarial evaluation of three top-ranked compounds (7e, 7g, and 7h) showed half-maximal inhibitory concentration values range from 53.85 to 100 µg/ml against chloroquine-sensitive strain 3D7 of Plasmodium falciparum. Compound 7e may be utilized as a lead for further optimization work in drug discovery due to good antimalarial activity.

Microwave-assisted synthesis of hybrid PABA-1,3,5-triazine derivatives as an antimalarial agent.

The present manuscript deals with the development of novel p-aminobenzoic acid (PABA) associated 1,3,5-triazine derivatives as antimalarial agents. The molecules were developed via microwave-assisted synthesis and structures of compounds were ascertained via numerous analytical and spectroscopic techniques. The synthesized compounds were also subjected to ADMET analysis. In a docking analysis, the title compounds showed high and diverse binding affinities towards wild (-162.45 to -369.38 kcal/mol) and quadruple mutant (-165.36 to -209.47 kcal/mol) Pf-DHFR-TS via interacting with Phe58, Arg59, Ser111, Ile112, Phe116. The in vitro antimalarial activity suggested that compounds 4e, 4b, and 4h showed IC50 ranging from 4.18 to 8.66 µg/ml against the chloroquine-sensitive (3D7) strain of Plasmodium falciparum. Moreover, compounds 4g, 4b, 4e, and 4c showed IC50 ranging from 8.12 to 12.09 µg/ml against chloroquine-resistant (Dd2) strain. In conclusion, our study demonstrated the development of hybrid PABA substituted 1,3,5-triazines as a novel class of Pf-DHFR inhibitor for antimalarial drug discovery.

Revisiting the levels of Aerosol Optical Depth in south-southeast Asia, Europe and USA amid the COVID-19 pandemic using satellite observations.

The countries around the world are dealing with air quality issues for decades due to their mode of production and energy usages. The outbreak of COVID-19 as a pandemic and consequent global economic shutdown, for the first time, provided a base for the real-time experiment of the effect of reduced emissions across the globe in abetting the air pollution issue. The present study dealt with the changes in Aerosol Optical Depth (AOD), a marker of air pollution, because of global economic shutdown due to the coronavirus pandemic. The study considered the countries in south and south-east Asia (SSEA), Europe and the USA for their extended period of lockdown due to coronavirus pandemic. Daily Aerosol Optical Depth (AOD) from Moderate-resolution imaging spectroradiometer (MODIS) and tropospheric column density of NO2 and SO2 from Ozone monitoring instrument (OMI) sensors, including meteorological data such as wind speed (WS) and relative humidity (RH) were analyzed during the pre-lockdown (2017-2019) and lockdown periods (2020). The average AOD, NO2 and SO2 during the lockdown period were statistically compared with their pre-lockdown average using Wilcoxon-signed-paired-rank test. The accuracy of the MODIS-derived AOD, including the changing pattern of AOD due to lockdown was estimated using AERONET data. The weekly anomaly of AOD, NO2 and SO2 was used for analyzing the space-time variation of aerosol load as restrictions were imposed by the concerned countries at the different points of time. Additionally, a random forest-based regression (RF) model was used to examine the effects of meteorological and emission parameters on the spatial variation of AOD. A significant reduction of AOD (-20%) was obtained for majority of the areas in SSEA, Europe and USA during the lockdown period. Yet, the clusters of increased AOD (30-60%) was obtained in the south-east part of SSEA, the western part of Europe and US regions. NO2 reductions were measured up to 20-40%, while SO2 emission increased up to 30% for a majority of areas in these regions. A notable space-time variation was observed in weekly anomaly. We found the evidence of the formation of new particles for causing high AOD under high RH and low WS, aided by the downward vertical wind flow. The RF model showed a distinguishable relative importance of emission and meteorological factors among these regions to account for the spatial variability of AOD. Our findings suggest that the continued lockdown might provide a temporary solution to air pollution; however, to combat persistent air quality issues, it needs switching over to the cleaner mode of production and energy. The findings of this study, thus, advocated for alternative energy policy at the global scale.

1,3,5-Triazine: A versatile pharmacophore with diverse biological activities.

1,3,5-Triazine and its derivatives have been the epicenter of chemotherapeutic molecules due to their effective biological activities, such as antibacterial, fungicidal, antimalarial, anticancer, antiviral, antimicrobial, anti-inflammatory, antiamoebic, and antitubercular activities. The present review represents a summarized report of the crucial biological activities possessed by substituted 1,3,5-triazine derivatives, with special attention to the most potent compounds.

Assessment of sal (Shorea robusta) forest phenology and its response to climatic variables in India.

Remote sensing-based observation provides an opportunity to study the spatiotemporal variations of plant phenology across the landscapes. This study aims to examine the phenological variations of different types of sal (Shorea robusta) forests in India and also to explore the relationship between phenology metrics and climatic parameters. Sal, one of the main timber-producing species of India, can be categorized into dry, moist, and very moist sal. The phenological metrics of different types of sal forests were extracted from Moderate Resolution Imaging Spectroradiometer (MODIS)-derived Enhanced Vegetation Index (EVI) time series data (2002-2015). During the study period, the average start of season (SOS) was found to be 16 May, 17 July, and 29 June for very moist, moist, and dry sal forests, respectively. The spatial distribution of mean SOS was mapped as well as the impact of climatic variables (temperature and rainfall) on SOS was investigated during the study period. In relation to the rainfall, values of the coefficient of determination (R2) for very moist, moist, and dry sal forests were 0.69, 0.68, and 0.76, respectively. However, with temperature, R2 values were found higher (R2 = 0.97, 0.81, and 0.97 for very moist, moist, and dry sal, respectively). The present study concluded that MODIS EVI is well capable of capturing the phenological metrics of different types of sal forests across different biogeographic provinces of India. SOS and length of season (LOS) were found to be the key phenology metrics to distinguish the different types of sal forests in India and temperature has a greater influence on SOS than rainfall in sal forests of India.

Recent trends in the development of peptide and protein-based hydrogel therapeutics for the healing of CNS injury.

Traumatic brain injury (TBI) and spinal cord injury (SCI) cause millions of deaths and permanent or prolonged physical disabilities around the globe every year. It generally happens due to various incidents, such as accidents during sports, war, physical assault, and strokes which result in severe damage to brain and spinal cord. If this remains untreated, traumatic CNS injuries may lead to early development of several neurodegenerative diseases like Alzheimer's, Parkinson, multiple sclerosis, and other mental illnesses. The initial physical reaction, which is also termed as the primary phase, includes swelling, followed by inflammation as a result of internal haemorrhage causing damage to indigenous tissue, i.e., axonal shear injury, rupture of blood vessels, and partial impaired supply of oxygen and essential nutrients in the neurons, thereby initiating a cascade of events causing secondary injuries such as hypoxia, hypotension, cognitive impairment, seizures, imbalanced calcium homeostasis and glutamate-induced excitotoxicity resulting in concomitant neuronal cell death and cumulative permanent tissue damage. In the modern era of advanced biomedical technology, we are still living with scarcity of the clinically applicable comparative non-invasive therapeutic strategies for regeneration or functional recovery of neurons or neural networks after a massive CNS injury. One of the key reasons for this scarcity is the limited regenerative ability of neurons in CNS. Growth-impermissive glial scar and the lack of a synthetic biocompatible platform for proper neural tissue engineering and controlled supply of drugs further retard the healing process. Injectable or implantable hydrogel materials, consisting majorly of water in its porous three-dimensional (3D) structure, can serve as an excellent drug delivery platform as well as a transplanted cell-supporting scaffold medium. Among the various neuro-compatible bioinspired materials, we are limiting our discussion to the recent advancement of engineered biomaterials comprising mainly of peptides and proteins due to their growing demand, low immunogenicity and versatility in the fabrication of neuro regenerative medicine. In this article, we try to explore all the recent scientific avenues that are developing gradually to make peptide and peptide-conjugated biomaterial hydrogels as a therapeutic and supporting scaffold for treating CNS injuries.

A bis-indole/carbazole based C5-curcuminoid fluorescent probe with large Stokes shift for selective detection of biothiols and application to live cell imaging.

A series of heterocyclic C5-curcuminoids (bis(arylmethylidene)acetones) (PJ1-PJ6) having a large Stokes shift (Δλ = 104-173 nm) have been synthesized for the selective detection of cysteine (Cys), homocysteine (Hcy) and glutathione (GSH) in living cells. The compounds were synthesized using a new methodology via deacetylation under microwave conditions. The photophysical properties of these compounds have been studied. Prominent colour changes from bright yellow to colourless in the presence of thiols were observed for PJ1. Live cell imaging has been employed with PJ1 for the utilization of the probe to detect homocysteine in A375 cells and apoptosis in AGS cells.

Acute and sub-chronic toxicity studies of Benincasa hispida (Thunb.) cogniaux fruit extract in rodents.

The objective of the present study was to evaluate the safety of standardized 70% ethanolic extract of Benincasa hispida fruit pulp (HABH) in rodents. Chemical characterization of HABH has been done by GC-MS and dimethylsulfoxonium formyl methylide, l-(+)-ascorbic acid and 2,6-dihexadecanoate were identified as major compounds in the extract. Acute oral toxicity study of HABH was done according to the Organization for Economic Cooperation and Development (OECD) guideline, by 'up and down' method, using the limit test at 2000 mg/kg, body weight in mice and were observed up to 14 days. In sub-chronic oral toxicity study, HABH was administered to Wistar rats at doses of 1000, 200 and 40 mg/kg b. w. per day for 90 days. In acute toxicity study, there was no mortality and no behavioural signs of toxicity at the limit test dose level (2000 mg/kg b. w.). In sub-chronic oral toxicity study, there was no significant difference observed in the consumption of food and water, body weight and relative organ weights. Haematological, serum biochemical and urine analysis revealed the non-adverse effects of prolonged oral consumption of HABH. The histopathologic examination did not show any differences in vital organs. Based on our findings, HABH, at dosage levels up to 1000 mg/kg b. w., is non-toxic and safe for long term oral consumption.

Are phenological variations in natural teak (Tectona grandis) forests of India governed by rainfall? A remote sensing based investigation.

Monitoring and assessment of vegetation phenology at the regional to global scale are essential to understand the characteristics of various biophysical parameters in terrestrial ecosystems. Passive optical remote sensing data have been used extensively in the recent past to study phenology of vegetation, also called land surface phenology, at diverse landscapes across the globe. In the present study, the moderate resolution imaging spectroradiometer (MODIS)-derived enhanced vegetation index (EVI) time series data (2000-2013) was used to study the phenology of dry and moist teak (Tectona grandis) forests of different biogeographic provinces of India. Four phenology metrics, viz., start of season (SOS), end of season (EOS), peak of season (POS) and length of season (LOS) were derived using the TIMESAT tool. The SOSs' of dry and moist teak were found during July-August. LOS of moist teak was found to be much longer (~ 48 days) than dry teak. Also, a significant difference of leaf area index (LAI) (~ 2.8) of dry and moist teak forests was noticed during peak season from MODIS LAI product (MOD15A2). Vegetation phenology is greatly responsive to the fluctuation of climatic parameters such as rainfall. Hence, pre-season cumulative rainfall data were analysed to understand the control of rainfall over phenological variations in natural teak forests of India. It was noticed that rainfall was reasonably well correlated with SOS (R2 = 0.57-0.72) for both types of teak forests. The study highlighted the efficacy of time series MODIS EVI data to study the phenological variations in different teak forest types of India in a data-limited situation.

Assessment of historical forest cover loss and fragmentation in Asian elephant ranges in India.

India is home of the largest remaining population of the Asian elephant (Elephas maximus L.) in the South and Southeast Asia. The forest loss and fragmentation is the main threat to the long-term survival of Asian elephants. In the present study, we assessed forest loss and fragmentation in the major elephant ranging provinces in India, viz., north-eastern, north-western, central, and southern since the 1930s. We quantified forest cover changes by generating and analyzing forest cover maps of 1930, 1975, and 2013, whereas fragmentation of contiguous forest areas was quantified by applying landscape metrics on the temporal forest cover maps. A total of 21.49% of the original forest cover was lost from 1930 to 1975, while another 3.19% forest cover was lost from 1975 to 2013 in the elephant ranges in India. The maximum forest loss occurred in the southern range (13,084 km2) followed by north-eastern (10,188 km2), central (5614 km2), and north-western (4030 km2) elephant ranges in the past eight decades. The forests in the central range were the most fragmented followed by southern, north-eastern, and north-western elephant ranges. The forest fragmentation in the southern range occurred at the fastest rate than central, north-eastern, and north-western ranges. The core forest areas shrunk by 39.6% from 1930 to 2013. The causative factors of forest change and situation of elephant-human conflict have been discussed. Study outcomes would be helpful in planning effective conservation strategies for Asian elephants in India.