A helping strand: A method to selectively form copper nanoparticles in solution using double‐stranded DNA has been developed. The size of the nanoparticles is controlled by the length of the dsDNA ...template, and single‐stranded DNA did not act as a template (see scheme). Single‐stranded overhangs in dsDNA were used to prepare a nanostructure in which two metallized dsDNA segments were linked together by a nonmetallized rigid linker.
The bacterial wilt disease of solanaceous crops incited by Ralstonia solanacearum is a menace to the production of solanaceous vegetables all over the world. Among the agro climatic zones of West ...Bengal, India growing solanaceous vegetables, the maximum and minimum incidence of bacterial wilt was observed in Red and Lateritic zone (42.4%) and Coastal and Saline zone (26.9%), respectively. The present investigation reports the occurrence of bacterial wilt of Bottle gourd by R. solanacearum Sequevar 1-48 for the first time in India. Two new biovars (6 and 3b) along with biovar 3 have been found to be prevalent in West Bengal. Under West Bengal condition, the most predominant Sequevar was I-48 (75%) followed by I-47 (25%). Low genetic variation (18.9%) among agro climatic zones (ACZs) compared to high genetic variation (81.1%) within revealed occurrence of gene flow among these ACZs. Standard genetic diversity indices based on the concatenated sequences of the seven genes revealed ACZ-6 as highly diverse among five agro climatic zones. The multi locus sequence analysis illustrated occurrence of synonymous or purifying selection in the selected genes in West Bengal and across world. Under West Bengal conditions maximum nucleotide diversity was observed for the gene gyrB. Occurrence of significant recombination was confirmed by pairwise homoplasy test (theta = 0.47*) among the RSSC isolates of West Bengal, belonging to Phylotype I. Phylotype I isolates of West Bengal are involved in exchange of genetic material with Phylotype II isolates. In case of worldwide RSSC collection, eleven significant recombination events were observed among the five phylotypes. Phylotype IV was genetically most diverse among all the Phylotypes. The most recombinogenic phylotype was Phylotype III. Further, the most diverse gene contributing to the evolution of RSSC worldwide was observed to be endoglucanase (egl).
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Racemates often have lower solubility than enantiopure compounds, and the mixing of enantiomers can enhance the aggregation propensity of peptides. Amyloid beta (Aβ) 42 is an aggregation‐prone ...peptide that is believed to play a key role in Alzheimer's disease. Soluble Aβ42 aggregation intermediates (oligomers) have emerged as being particularly neurotoxic. We hypothesized that the addition of mirror‐image d‐Aβ42 should reduce the concentration of toxic oligomers formed from natural l‐Aβ42. We synthesized l‐ and D‐Aβ42 and found their equimolar mixing to lead to accelerated fibril formation. Confocal microscopy with fluorescently labeled analogues of the enantiomers showed their colocalization in racemic fibrils. Owing to the enhanced fibril formation propensity, racemic Aβ42 was less prone to form soluble oligomers. This resulted in the protection of cells from the toxicity of l‐Aβ42 at concentrations up to 50 μm. The mixing of Aβ42 enantiomers thus accelerates the formation of non‐toxic fibrils.
The mixing of the two enantiomers of Aβ42 leads to a drastic acceleration of fibrillization. By using fluorescently labeled analogues, it was shown that the degree of enantiomer colocalization in racemic fibrils is high. The reduced propensity of the racemate to yield oligomeric aggregation intermediates resulted in inhibition of the toxicity of the natural l‐Aβ42 enantiomer in the racemate.
The Mirik lake is a well-known tourist destination in the Darjeeling Himalayan region of West Bengal. In the last few decades, the lake area experienced a surge in demand for the hospitality industry ...with the consequences of unrestricted municipal town growth. On this perspective, this research work addresses the contemporary problems of the Mirk municipality area involving the lake system using technologies of remote sensing and GIS. In accordance with the primary objective, the detailed land use/land cover change analysis of the past twenty years shows a significant escalating trend in built-up area as it has increased from 149.85 ha in 2000 to 178.25 ha in 2020, where the lake expresses a steady reduction of its perennial part. The gradual shrinkage in the lake area may become of grave concern and therefore, this particular work tries to examine the water quality parameters of Mirik lake. Analyses have shown that the lake shrinkage may be attributed to waste disposal, landfill pollution etc., substantially contributed to the raised level of suspended sediment concentration (3724.26 mg/lit in 2020) near the boundaries. Moreover, the outcome of the developed water pollution model identifies that the western and south-western parts of the lake are the most polluted regions and confirms numerous inlets of the western side push up the level of phosphorus, nitrogen and biological oxygen demand in lake water. Such lake degradation is a real threat to the mountainous lacustrine environment, and it requires comprehensive plans for better management practices at some regular interregnum.
Trade-off between energy conservation and efficiency is one of the most important issues in designing Wireless Sensor Network (WSN) based applications. Network life time is primarily determined by ...the life time of battery. Recently, energy harvesting techniques that will recharge the battery in different non-conventional ways are being investigated by researchers. In this paper, an adaptive cross layer protocol is proposed which will provide trade off between energy harvesting time and active time for message transmission with the aim of increasing network lifetime. Depending on the value of various network parameters like, remaining energy of node, node density, message density in a particular region of the network, the cross-layer protocol will change its policy. The paper also proposes a cluster head selection method that ensures maximum network life time and higher quality of service. The result shows an overall increase in network lifetime as compared to other protocols.
There are different methods of optimizing energy usage of sensor nodes for increasing the life time of wireless sensor network. The first node death time is considered to be the effective life time ...of any network. Therefore, our objective is to adopt such routing algorithms and node deployment policy so that no individual node dies sooner while others are alive. There are different reasons for the early death of first node, which at extreme cases may lead to partition of the network. One of the important reasons for which node energy might run out early is that number of transmitted messages per geographic area unit is different. A node is more likely to run out of its energy earlier than the others in an area where message density is high. Therefore, if we can predict the areas in the network where message density is likely to be higher than the rest of the area in the network, then we can increase node density while aiming at uniform energy dissipation. The nodes which reside nearer to the sink node face huge traffic load that lead to non-uniform energy dissipation. Hence, node density nearer to the sink node has to be increased. In this paper, to increase the lifespan of wireless sensor network, we explore this concept to obtain the best possible solution.
The decline of honey bee (Apis mellifera L.) populations is of great concern around the world. Among the several key drivers, dissemination of pests and pathogens is potential one. Chalkbrood is very ...common fungal disease of honey bee, caused due to Ascosphaera apis. In the present study, survey was conducted regarding the prevalence of diseases in A. mellifera beekeeping in Gangetic plains of West Bengal, India. Results confirmed the occurrence of chalkbrood disease in different apiaries, where dead and mummified bee larvae with cotton like chalky white or greyish-black covering were found as physical symptoms of the disease. From three surveyed apiaries, a total of 16 hives out of 113 hives were found to be infected with the diseases; and 46 frames out of 132 frames from the infected 16 hives were found to be affected by the pathogen. Microscopic examination reflected that nearly 87% of the samples collected from the infected frame were found to be positive for the spore of Ascosphaera. The fungus associated with the disease was isolated on Potato Dextrose Agar medium, pure cultured and its genomic DNA was isolated to perform PCR and based on 18s rDNA sequencing by using specific primer pair of ITS-1 and ITS-4, the fungus was identified as Ascosphaera apis.
Keywords: 18s rDNA, Bees, Necrotrophs, Phylogeny
Lentil is a food legume grown in the Indo-Gangetic plains including lower Gangetic Bengal (LGB). Lentil productivity in this zone is severely impeded because of the prevalence of several biotic cues. ...Plausible reports regarding the status of disease scenario and the associated risk factors are missing. Therefore, judicious crop management strategies are lacking. An intensive survey of 267 farmers' fields was conducted over 3 years in major lentil-growing districts of LGB to evaluate the disease incidence and prevalence. Additional insights were generated, apprehending isolation and characterisation of associated pathogens through spore morphology and molecular markers as well as elucidating the role of biophysical factors in influencing disease development. Climate change has shifted the disease dimension of lentil and precipitated new disease complexes of great risk, which was reflected through geospatial mapping results in the present study. The prevalence of three major diseases, namely collar rot (
), lentil blight complex (LBC) incited by both
and
, and lentil rust (
), was ascertained through cultural and molecular studies and contextualised through pathogenicity appraisal. This study is the first to investigate the complex mixed infection of
and
, successfully isolating
in India, and confirming the pathogens through sequencing by using internal transcribed spacer (ITS) primers and
-specific Glycerol-3-phosphate dehydrogenase 1 (gpd1) and gpd2 primers. Unlike late planting, early planting promoted collar rot infestation. LBC and rust incidence were magnified in late planting. Soil texture resulted in the spatial distribution of collar rot disease. The surveyed data also highlighted the potential role of resistant cultivars and cropping pattern intervention to ensure associational resistance towards addressing the disease bottleneck in lentil.
In the wireless sensor network, several sensor devices are distributed in an environment with a goal to collect data and then forward it to a base station which could be then later used for some ...study such as changes in the environment. They are distributed across environment and are fitted with a battery. Due to their small size the size of battery is also small. Several protocols are designed to reduce the energy consumption to improve the network life. One of the famous protocols is Low Energy Adaptive Clustering Hierarchy (LEACH). In this paper, our main focus is to make changes to the original LEACH protocol to reduce energy consumption. We designed two algorithms: Modified Multihop (MMH) LEACH and Modified Cluster Head (MCH) LEACH. Both the algorithms perform better than the original LEACH protocol in terms of remaining energy. Network life is also improved when they were distributed in a bigger environment. The energy consumption is reduced than the original LEACH protocol.
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