216 research outputs found

    Tea mosquito bug (Helopeltis spp.) – A devastating pest of cashew plantations in India: A review

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    More than 32 countries are growing cashew in the world, wherein India occupies largest area under cashew plantations (20%) and earning foreign exchange of over 5 000 crores per annum through export of cashew kernels and cashew nut shell liquid. Often, there is a serious loss in cashew nut yield due to attack of tea mosquito bug (Helopeltis spp., Heteroptera: Miridae) which is a major sucking pest of cashew plantations in India. Under severe out break conditions, yield losses are as high as 40-50%. There are three common species of Helopeltis, viz. H. antonii Signoret, H. bradyi Waterhouse and H. theivora Waterhouse found in west coast and H. antonii is most predominant in the east coast, though in east coast its occurrence is prevalent from Tamil Nadu to Odisha. Whereas, H. theivora is predominant species in north-east region. Besides cashew, a large number of host plants like, tea, guava, cocoa, neem, cinchona etc. are reported. The seasonality study suggested that the population of tea mosquito bug reaches its peak during the flushing, flowering and fruiting season in cashew, i.e. from November to February. As a management strategy, varietal screening suggested that no cashew varieties are resistant to tea mosquito bug infestation but Dhana and Bhaskara varieties are moderately susceptible. Therefore, even today only chemical means of tea mosquito bug management is adopted under commercial cashew plantation. As a biological control strategy, the solitary egg parasitoids, viz. Telenomus cuspis, Chaetostricha sp. and Erythmelus helopeltidis Gahan were specifically promising against Helopeltis. The adult parasitoid, Leiophron sp. is additional asset for natural control strategies of Helopeltis spp. on cashew. Recent researches have incorporated 117 species of spiders and 18 species of reduviids into cashew management strategies. Laboratory mass culture techniques of reduviids have also been standardized using wax moth larvae as prey. Adults of H. antonii and H. theivora were found to be infested by predatory mite, Leptus sp. attached ecdysial line from head and thorax. Moreover, sex pheromone based technology development is the need of the hour to manage this pest. In this paper, efforts have been made to review the literature pertaining to the pest taxonomy, biology, distribution, host plants, nature of damage, seasonality and management strategy of Helopeltis spp. focusing on Indian subcontinent, so as to bring out non-chemical based management strategies

    Effect of blanching treatments and dehydration methods on rehydration quality of khejri (Prosopis cineraria) pods

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    The khejri (Prosopis cineraria L. Druce), is a multipurpose leguminous tree of hot arid desert. Its tender pods are utilized for culinary purpose both in fresh and dehydrated conditions without ascertaining its quality aspect. Therefore, the present investigation was carried out to find out the effect of blanching treatments and dehydration methods on rehydration quality of khejri pods. The experiment consists of three methods of drying and six blanching treatments replicated thrice under completely randomised design (CRD). Both tender pods (harvested within 20 days of fruit set at green stage) and mature pods (harvested after 25 days of fruit set at colour turning stage) were taken for the study. Among various methods of drying; sun drying took minimum time (11 hours) while other methods took comparatively longer period for drying. Moreover, recovery per cent of pods did not vary significantly within the drying methods and blanching treatments. In general, tender pods recovery was less compared to matured pods. The rehydration ratio was maximum in pods blanched in hot water (5 min.) followed by control. Among different methods, the rehydration ratio was maximum in shade drying followed by sun drying and the least in tray drier. The storage life of dehydrated pods was more than 52 weeks in blanching treatment than only about 8 weeks in control (un-blanched pods). The appearance of sun dried pods was not good as brownish and grayish colour pods were observed. Whereas in case of pods dried in shade and tray drier were green in colour. The protein content was also higher in pods dehydrated either in shade or in tray drier but the differences among the blanching treatments were non-significant. Thus, it can be concluded that the tender pods dried after blanching in 2 per cent salt solution (5 min.) or blanched in 2 per cent salt solution (5 min.) + 0.1 per cent KMS (potassium metabisulphite) either in shade or in tray drier have overall good acceptability because of retention of green colour, higher protein content, good storage life, better appearance after rehydration, good culinary taste, overall higher hedonic rating and more hygienic conditions than open sun drying

    SOCIO-PSYCHOLOGICAL STUDY AMONG INJECTABLE DRUG USERS IN KATHMANDU VALLEY

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    On the background of ever increasing HIV transmission in our community through various routes, the psychosocial factors related with intravenous drug abuse has become necessary to be studied. Aim of the study was to assess the Socio-psychological factors that influence people to use drugs, especially to use Injectable drugs. We enrolled a sample of 393 Intravenous drug users, all male, in the Kathmandu Valley. Participants were administered a semi structured proforma to assess the psychosocial issues related with the drug intravenous drug abuse. Mean age of the sample was 27.76+ 4.86 years. Majority were single, unemployed, Hindu and by caste Newars, with education more than high school (SLC or more). The first psychoactive substance use by most of them was cannabis. The most frequently used psychoactive substance was injection Buprenorphine (Tidigesic), which was followed by mixture of various substances (opiates, benzodiazepines, antihistamines) and Diacetyl morphine (Brown sugar). Factors associated with the start of the drugs were for enjoyment, friend’s pressure and to alleviate mental tension. Many accepted Injectable drug use contributing to problems in mental, marital, social, economic and legal aspects of their life. Despite knowing the harms caused by the drugs majority persist on its use. A needle exchange programme has been viewed positively by many. Key words: buprenorphin, needle sharing, needle replacement, HIV transmission

    A ferromagnetic Eu-Pt surface compound grown below hexagonal boron nitride

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    One of the fundamental applications for monolayer-thick 2D materials is their use as protective layers of metal surfaces and in situ intercalated reactive materials in ambient conditions. Here we investigate the structural, electronic, and magnetic properties, as well as the chemical stability in air of a very reactive metal, Europium, after intercalation between a hexagonal boron nitride (hBN) layer and a Pt substrate. We demonstrate that Eu intercalation leads to a hBN-covered ferromagnetic EuPt2 surface alloy with divalent Eu2+ atoms at the interface. We expose the system to ambient conditions and find a partial conservation of the di-valent signal and hence the Eu-Pt interface. The use of a curved Pt substrate allows us to explore the changes in the Eu valence state and the ambient pressure protection at different substrate planes. The interfacial EuPt2 surface alloy formation remains the same, but the resistance of the protecting hBN layer to ambient conditions is reduced, likely due to a rougher surface and a more discontinuous hBN coating

    Effect of Layer-Stacking on the Electronic Structure of Graphene Nanoribbons

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    The evolution of electronic structure of graphene nanoribbons (GNRs) as a function of the number of layers stacked together is investigated using \textit{ab initio} density functional theory (DFT) including interlayer van der Waals interactions. Multilayer armchair GNRs (AGNRs), similar to single-layer AGNRs, exhibit three classes of band gaps depending on their width. In zigzag GNRs (ZGNRs), the geometry relaxation resulting from interlayer interactions plays a crucial role in determining the magnetic polarization and the band structure. The antiferromagnetic (AF) interlayer coupling is more stable compared to the ferromagnetic (FM) interlayer coupling. ZGNRs with the AF in-layer and AF interlayer coupling have a finite band gap while ZGNRs with the FM in-layer and AF interlayer coupling do not have a band gap. The ground state of the bi-layer ZGNR is non-magnetic with a small but finite band gap. The magnetic ordering is less stable in multilayer ZGNRs compared to single-layer ZGNRs. The quasipartcle GW corrections are smaller for bilayer GNRs compared to single-layer GNRs because of the reduced Coulomb effects in bilayer GNRs compared to single-layer GNRs.Comment: 10 pages, 5 figure

    Cryptic Eimeria genotypes are common across the southern but not northern hemisphere

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    The phylum Apicomplexa includes parasites of medical, zoonotic and veterinary significance. Understanding the global distribution and genetic diversity of these protozoa is of fundamental importance for efficient, robust and long-lasting methods of control. Eimeria spp. cause intestinal coccidiosis in all major livestock animals and are the most important parasites of domestic chickens in terms of both economic impact and animal welfare. Despite having significant negative impacts on the efficiency of food production, many fundamental questions relating to the global distribution and genetic variation of Eimeria spp. remain largely unanswered. Here, we provide the broadest map yet of Eimeria occurrence for domestic chickens, confirming that all the known species (Eimeria acervulina, Eimeria brunetti, Eimeria maxima, Eimeria mitis, Eimeria necatrix, Eimeria praecox, Eimeria tenella) are present in all six continents where chickens are found (including 21 countries). Analysis of 248 internal transcribed spacer sequences derived from 17 countries provided evidence of possible allopatric diversity for species such as E. tenella (FST values ⩽0.34) but not E. acervulina and E. mitis, and highlighted a trend towards widespread genetic variance. We found that three genetic variants described previously only in Australia and southern Africa (operational taxonomic units x, y and z) have a wide distribution across the southern, but not the northern hemisphere. While the drivers for such a polarised distribution of these operational taxonomic unit genotypes remains unclear, the occurrence of genetically variant Eimeria may pose a risk to food security and animal welfare in Europe and North America should these parasites spread to the northern hemisphere

    Analysis of Aurora kinase A expression in CD34+ blast cells isolated from patients with myelodysplastic syndromes and acute myeloid leukemia

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    Aurora kinase A, also known as aurora A, is a serine/threonine kinase that plays critical roles in mitosis entry, chromosome alignment, segregation, and cytokinesis. Overexpression of aurora A has been observed in many solid tumors and some hematopoietic neoplasms, but little is known about its expression in myeloid diseases. Because cytogenetic abnormalities play an essential role in the pathogenesis of myeloid malignancies, we hypothesized that aurora A deregulation may be involved in myelodysplastic syndromes and acute myeloid leukemia and contribute to the chromosomal instability observed in these diseases. We assessed aurora A mRNA levels in CD34+ bone marrow blasts from nine patients with acute myeloid leukemia, 20 patients with myelodysplastic syndromes, and five normal patients serving as controls. CD34+ blasts were isolated from bone marrow aspirate specimens using magnetic activated cell separation technology. RNA was extracted from purified CD34+ cells, and quantitative real-time reverse transcriptase polymerase chain reaction for aurora A was performed. Immunocytochemical analyses for total aurora A, phosphorylated aurora A, Ki-67, and activated caspase 3 were performed on cytospin slides made from purified CD34+ cells in myelodysplastic syndrome patients using standard methods. Aurora A mRNA and protein levels were correlated, as was aurora A mRNA level, with blast counts, cytogenetic abnormalities, and International Prognostic Scoring System score. We found that CD34+ cells in myelodysplastic syndromes and acute myeloid leukemia expressed aurora A at significantly higher levels (P = 0.01 and P = 0.01, respectively) than normal CD34+ cells. Aurora A mRNA levels correlated with total and phosphorylated protein levels (P = 0.0002 and P = 0.02, respectively). No significant correlation was found between aurora A mRNA level and blast count, blast viability, cytogenetic abnormalities, or the International Prognostic Scoring System score in patients with myelodysplastic syndromes. We conclude that aurora A is up-regulated in CD34+ blasts from myeloid neoplasms

    Synoptic analysis and WRF-Chem model simulation of dust events in the Southwestern United States

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    Dust transported from rangelands of the Southwestern United States (US) to mountain snowpack in the Upper Colorado River Basin during spring (March-May) forces earlier and faster snowmelt, which creates problems for water resources and agriculture. To better understand the drivers of dust events, we investigated large-scale meteorology responsible for organizing two Southwest US dust events from two different dominant geographic locations: (a) the Colorado Plateau and (b) the northern Chihuahuan Desert. High-resolution Weather Research and Forecasting coupled with Chemistry model (WRF-Chem) simulations with the Air Force Weather Agency dust emission scheme incorporating a MODIS albedo-based drag-partition was used to explore land surface-atmosphere interactions driving two dust events. We identified commonalities in their meteorological setups. The meteorological analyses revealed that Polar and Sub-tropical jet stream interaction was a common upper-level meteorological feature before each of the two dust events. When the two jet streams merged, a strong northeast-directed pressure gradient upstream and over the source areas resulted in strong near-surface winds, which lifted available dust into the atmosphere. Concurrently, a strong mid-tropospheric flow developed over the dust source areas, which transported dust to the San Juan Mountains and southern Colorado snowpack. The WRF-Chem simulations reproduced both dust events, indicating that the simulations represented the dust sources that contributed to dust-on-snow events reasonably well. The representativeness of the simulated dust emission and transport in different geographic and meteorological conditions with our use of albedo-based drag partition provides a basis for additional dust-on-snow simulations to assess the hydrologic impact in the Southwest US

    The Role of T cell PPAR γ in mice with experimental inflammatory bowel disease

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    <p>Abstract</p> <p>Background</p> <p>Peroxisome proliferator-activated receptor γ (PPAR γ) is a nuclear receptor whose activation has been shown to modulate macrophage and T cell-mediated inflammation. The objective of this study was to investigate the mechanisms by which the deletion of PPAR γ in T cells modulates immune cell distribution and colonic gene expression and the severity of experimental IBD.</p> <p>Methods</p> <p>PPAR γ flfl; CD4 Cre<sup>+ </sup>(CD4cre) or Cre- (WT) mice were challenged with 2.5% dextran sodium sulfate in their drinking water for 0, 2, or 7 days. Mice were scored on disease severity both clinically and histopathologically. Flow cytometry was used to assess lymphocyte and macrophage populations in the blood, spleen, and mesenteric lymph nodes (MLN). Global gene expression in colonic mucosa was profiled using Affymetrix microarrays.</p> <p>Results</p> <p>The deficiency of PPAR γ in T cells accelerated the onset of disease and body weight loss. Examination of colon histopathology revealed significantly greater epithelial erosion, leukocyte infiltration, and mucosal thickening in the CD4cre mice on day 7. CD4cre mice had more CD8<sup>+ </sup>T cells than WT mice and fewer CD4<sup>+</sup>FoxP3<sup>+ </sup>regulatory T cells (Treg) and IL10<sup>+</sup>CD4<sup>+ </sup>T cells in blood and MLN, respectively. Transcriptomic profiling revealed around 3000 genes being transcriptionally altered as a result of DSS challenge in CD4cre mice. These included up-regulated mRNA expression of adhesion molecules, proinflammatory cytokines interleukin-6 (IL-6) and IL-1β, and suppressor of cytokine signaling 3 (SOCS-3) on day 7. Gene set enrichment analysis (GSEA) showed that the ribosome and Krebs cycle pathways were downregulated while the apoptosis pathway was upregulated in colons of mice lacking PPAR γ in T cells.</p> <p>Conclusions</p> <p>The expression of PPAR γ in T cells is involved in preventing gut inflammation by regulating colonic expression of adhesion molecules and inflammatory mediators at later stages of disease while favoring the recruitment of Treg to the mucosal inductive sites.</p
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