381 research outputs found
Assessment of herbaceous biomass: A study in Rowghat mining areas of Chhattisgarh, India
We studied Rowghat sites of Chhattisgarh, India, with the objective to assess herbaceous layer composition, biomass and to prepare management implications for conservation of ecologically sensitive species in mined areas. Ten sites (Anjrel, Khodgaon, Khadkagaon, Takrel, Rav Dongri, Tarhur, Godenmar Dongri, Parmad Dongri, Bhusujkun Dongri and Bedhiyar Nala) were selected for the study. We randomly placed quadrats of 1x1 m size in each site. A sum of 36 species distributed in 15 families were encountered in Rowghat mining site. The total density of all herbs was highest (724000) in Bhusujkun Dongri followed by Khadkagaon (678000), Rav Dongri (662000) and lowest was recorded from Godenmar Dongri (502000). The density of herbs across the study area ranged from 9,000 (D. ciliaris) to 2,50,000 (S. viridis) in the areas of Tarhur and Bediyar Nala. The herb species were unevenly distributed across mined areas. The Chlorophytum tuberosum and Cassia tora were recorded only from Tarkel and Godenmar Dongri sites, respectively. The total belowground biomass ranged between 0.097 t/ha in Godenmar Dongri to 0.18 t/ha in Rav Dongri. An ecological approach is must to restore the collieries. Protection of ecologically sensitive herbs is necessary. Prolonged ban on mining activity in Rowghat forest area is needed to restore degraded forest
Modulation of HLA antigens in response to the binding of epidermal growth factor by A431 cells
AbstractIn a previous study [(1984) J. Cell Biol. 98, 725â731] we showed that the level of human MHC, HLA antigens on A431 carcinoma cells is reduced after these cells bind epidermal growth factor (EGF). Here we use flow cytometry to determine the effects of various doses and times of EGF treatment on HLA expression. We then show that the reduction in HLA expression is associated with a reduction in the level of phosphorylation of immunoprecipitable surface HLA antigens, although longer exposure of cells with EGF increased both surface HLA expression and their phosphorylation levels. Lateral diffusion of HLA antigens is lower in EGF-treated than in control cells. The lower diffusion coefficients measured may be causally related to the decreased phosphorylation of HLA antigens
Transcriptional Response of Selenopolypeptide Genes and Selenocysteine Biosynthesis Machinery Genes in Escherichia coli during Selenite Reduction
This work was supported by a United States Department of Agriculture-Cooperative State Research, Education, and Extension Service grant (no. 2009-35318-05032), a Biotechnology Research grant (no. 2007-BRG-1223) from the North Carolina Biotechnology Center, and a startup fund from the Golden LEAF Foundation to the Biomanufacturing Research Institute and Technology Enterprise (BRITE).Bacteria can reduce toxic selenite into less toxic, elemental selenium (Se0), but the mechanism on how bacterial cells reduce selenite at molecular level is still not clear. We used Escherichia coli strain K12, a common bacterial strain, as a model to study its growth response to sodium selenite (Na2SeO3) treatment and then used quantitative real-time PCR (qRT-PCR) to quantify transcript levels of three E. coli selenopolypeptide genes and a set of machinery genes for selenocysteine (SeCys) biosynthesis and incorporation into polypeptides, whose involvements in the selenite reduction are largely unknown. We determined that 5âmM Na2SeO3 treatment inhibited growth by âź50% while 0.001 to 0.01âmM treatments stimulated cell growth by âź30%. Under 50% inhibitory or 30% stimulatory Na2SeO3 concentration, selenopolypeptide genes (fdnG, fdoG, and fdhF) whose products require SeCys but not SeCys biosynthesis machinery genes were found to be induced âĽ2-fold. In addition, one sulfur (S) metabolic gene iscS and two previously reported selenite-responsive genes sodA and gutS were also induced âĽ2-fold under 50% inhibitory concentration. Our findings provide insight about the detoxification of selenite in E. coli via induction of these genes involved in the selenite reduction process.Publisher PDFPeer reviewe
Pregnancy outcome in a rare case of complex cyanotic congenital heart disease
A 28 year old primigravida with the very rare congenital heart condition of single ventricle with single atrium presented with 34 weeks gestation, and underwent caesarean section with minimal morbidity. As the condition is not known for survival into adulthood, the carrying of a pregnancy successfully to near term makes this an even rarer case
Rare case report of metastatic cervical carcinoma
Although carcinoma of cervix is among the most common malignancies in women, cutaneous metastasis is very unusual. Here we report a case of a parous woman diagnosed with adenocarcinoma of cervix who did not undergo chemotherapy in spite of being advised after initial surgery, presenting with cutaneous metastasis at the operative scar site 2 years later
Analysis of Sandwich Composites Using Anova Approach
Abstract--Sandwich construction finds its widespread application in the field of aerospace and consumer domain. Several types of core materials are used in the manufacture of sandwich composites. This paper provides an overview of the effect of foam core thickness and density of sandwich structure subjected to flatwise and edgewise compression followed by flexural test on PU foam based core material. Further ANOVA approach is used to determine the response surface methodology (RSM) of the specimen tested. Central composite design was adopted to study the RSM. The sandwich structure chosen here is made up of glass epoxy type and different density of 80kg/m 3 , 120kg/m 3 and 160kg/m 3 was chosen to study the mechanical properties
Crowdsourcing and Human Computation: Systems, Studies and Platforms
Crowdsourcing and human computation are transforming human-computer interaction, and CHI has led the way. The seminal publication in human computation was initially published in CHI in 2004 [1], and the first paper investigating Mechanical Turk as a user study platform has amassed over one hundred citations in two years [5]. However, we are just beginning to stake out a coherent research agenda for the field. This workshop will bring together researchers in the young field of crowdsourcing and human computation and produce three artifacts: a research agenda for the field, a vision for ideal crowdsourcing platforms, and a group-edited bibliography. These resources will be publically disseminated on the web and evolved and maintained by the community
Dynamics of conflicts in Wikipedia
In this work we study the dynamical features of editorial wars in Wikipedia
(WP). Based on our previously established algorithm, we build up samples of
controversial and peaceful articles and analyze the temporal characteristics of
the activity in these samples. On short time scales, we show that there is a
clear correspondence between conflict and burstiness of activity patterns, and
that memory effects play an important role in controversies. On long time
scales, we identify three distinct developmental patterns for the overall
behavior of the articles. We are able to distinguish cases eventually leading
to consensus from those cases where a compromise is far from achievable.
Finally, we analyze discussion networks and conclude that edit wars are mainly
fought by few editors only.Comment: Supporting information adde
Interpreting ambiguous âtraceâ results in Schistosoma mansoni CCA Tests: Estimating sensitivity and specificity of ambiguous results with no gold standard
Background The development of new diagnostics is an important tool in the fight against disease. Latent Class Analysis (LCA) is used to estimate the sensitivity and specificity of tests in the absence of a gold standard. The main field diagnostic for Schistosoma mansoni infection, Kato-Katz (KK), is not very sensitive at low infection intensities. A point-of-care circulating cathodic antigen (CCA) test has been shown to be more sensitive than KK. However, CCA can return an ambiguous âtraceâ result between âpositiveâ and ânegativeâ, and much debate has focused on interpretation of traces results. Methodology/Principle findings We show how LCA can be extended to include ambiguous trace results and analyse S. mansoni studies from both CĂ´te dâIvoire (CdI) and Uganda. We compare the diagnostic performance of KK and CCA and the observed results by each test to the estimated infection prevalence in the population. Prevalence by KK was higher in CdI (13.4%) than in Uganda (6.1%), but prevalence by CCA was similar between countries, both when trace was assumed to be negative (CCAtn: 11.7% in CdI and 9.7% in Uganda) and positive (CCAtp: 20.1% in CdI and 22.5% in Uganda). The estimated sensitivity of CCA was more consistent between countries than the estimated sensitivity of KK, and estimated infection prevalence did not significantly differ between CdI (20.5%) and Uganda (19.1%). The prevalence by CCA with trace as positive did not differ significantly from estimates of infection prevalence in either country, whereas both KK and CCA with trace as negative significantly underestimated infection prevalence in both countries. Conclusions Incorporation of ambiguous results into an LCA enables the effect of different treatment thresholds to be directly assessed and is applicable in many fields. Our results showed that CCA with trace as positive most accurately estimated infection prevalence
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