Mosquitoes transmit major communicable diseases such as dengue, malaria, filariasis, Japanese encephalitis, chikungunya, and so on. Vector control is important in epidemic disease situations as there is an urgent need to develop new and improved mosquito control methods that are economical and effective yet safe for non-targeted organisms. In the present study, silver nanoparticles (AgNPs) were synthesized from the aqueous leaf extract of neem plant (Azadirachta indica), and their effects on mosquito vectors (Aedes aegypti and Culex quinquefasciatus) were assessed. The synthesised AgNPs were characterized by UV-vis spectroscopy, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction analysis (XRD). The nanoparticles have maximum absorption at 442 ± 1.5 nm with an average size of 41-60 nm. The XRD data showed six well-defined diffraction peaks, corresponding to a relative intensity of the crystal structure of metallic silver 36.42, 100.00, 53.70, 14.20, 16.05, and 6.79, respectively. The FT-IR data showed strong prominent peaks in different ranges, reflecting its complex nature. The mosquito larvae were exposed to varying concentrations of AgNPs synthesized from the neem leaves under investigation (0.07-25 mg/l) for 24 h; this revealed larvicidal activity of AgNPs with LC50 and LC90 values of 0.006 and 0.04 mg/l for A. aegypti, respectively. Further, the LC50 and LC90 values were also identified as 0.047 and 0.23 mg/l for Cx. quinquefasciatus, respectively. The result obtained from this study presents biosynthesized silver nanoparticle from A. indica as the biolarvicidal agent with the most potential for mosquito control.

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Entomopathogenic bacteria to control mosquitoes are a promising environmentally friendly alternative to synthetic pesticides. In the present study, a novel mosquitocidal bacterium was isolated from marine soil collected from east coastal areas at Pondicherry (India). 16S rRNA gene sequence alignment depicted that this isolate belonged to Bacillus cereus VCRC-B520 (NCBI: KC-119192). Biochemical studies on bacterial growth, biomass, and toxin production have revealed that this strain could possibly be helpful in the production of a biopesticide in mosquito control. Toxicity assay with B. cereus against mosquito larvae has shown that the filariasis vector, Culex quinquefasciatus, is more susceptible than the other two species (Anopheles stephensi and Aedes aegypti). The LC50 and LC90 values for C. quinquefasciatus were 0.30 and 2.21 mg/L, respectively. No effect of B. cereus was found on nontargeted organisms. SDS-PAGE analysis and protein purification result from the cell mass of B. cereus have shown that a well-perceptible polypeptide was the dependable factor (85 kDa) for mosquitocidal action. Protein characterization (M/S MALDI-TOF) has shown that it is an endotoxin-specific insecticidal protein, namely "Cry4Aa". Phylogenetic analyses of 16S rDNA gene sequence from this marine isolate have revealed the presence of homology among closely related Bacillus strains. Therefore, considerable interest has been shown on the identification of a potential mosquitocidal bacterium from marine environment (B. cereus), which was not reported earlier in view of the current scenario of the rapid development of resistance to Bacillus sphaericus in mosquito vector control program.

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A novel mosquitocidal bacterium was isolated from marine soil. 16S rRNA gene sequence alignment depicted that this isolate belonged to the strain, Enterobacter cloacae VCRC-B519 (NCBI: KC119193). Biochemical studies such as bacterial growth, biomass production and protein (toxin) synthesis showed that the strain is plausibly useful for mosquito control. It showed an increasing pattern of toxicity for Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti, without negative effects for non-targeted organisms Chironomus riparius, Daphnia cephalata and Notonecta glauca. The qualitative analysis of the E. cloacae showed that three polypeptides (M.wt: 25, 30 and 50 kDa) were associated to the toxicity observed. The characterisation of these polypeptides (M/S MALDI-TOF)showed that they are enzymatic in nature. Consequently, the peptide sequences are identified to be polysugar degrading enzymes (25 kDa), cell wall associated hydrolases (30 kDa) and amino peptidase (50 kDa). Phylogenetic analyses of 16S rDNA gene sequence of E. cloacae revealed the occurrence of homology with closely related Enterobacter species. Therefore, it is concluded that the marine bacterium (Enterobacter cloacae)is possibly of use for the biological control of mosquito immatures.

The advent of technologies and equipments in Information Technology and Communication has increased the use of smart phones and social media by all people irrespective of age and gender. Many times people find social media posts as the outlet for draining all their emotions. Depression is a common mental health problem that ranges from low mood and loss of interest to persistent feeling of sadness and self-destruction. Mental Health Experts are interested in analyzing the physical and social media behavior of patients to diagnose depression. Attention Mechanism imitates the human cognitive of considering only the most relevant data needed for a particular analysis. LSTM is a state-of-the-art Recurrent Neural Network architecture used for depression analysis. In this paper we are further improving the LSTM Algorithm by proposing an Attention Mechanism that makes the model robust and improved. This major role of our Attention Mechanism is identifying the Prime Words and Supporting words that are relevant for the analysis. Distance is calculated between non-prime words and prime words, weights are assigned based on this calculation, higher weight being given to most relevant words. Making use of Attention helps us to focus only on the relevant data and neglect the irrelevant data.

Claude Berge [1] introduced the concept of strong stable set S in a graph. These sets are independent and any vertex outside S can have at most one neighbour in S. This concept was generalized by E . Sampathkumar and L. Pushpalatha [5]. A maximal independent set is a minimal dominating set. What type of domination will result from maximal semi-strong sets? This new type of domination which we call us -Three-connected domination is initiated and studied in this paper.