1,279 research outputs found
Reptiles sold as traditional medicine in Xipamanine and Xiquelene Markets (Maputo, Mozambique).
Zootherapy plays a role in healing practices in Mozambican society. Although several studies have focused on ethnobotany and traditional medicine in the country, little research has been conducted on the use of reptiles in zootherapy. The aim of this study was therefore to fill this gap by assessing the reptile species traded for traditional medicine in the Xipamanine and Xiquelene Markets in Maputo, Mozambique. We found that few reptile species are traded domestically for traditional medicine and that their use appears to be in decline in Mozambique. Our findings also suggest that the domestic trade of reptiles for traditional medicines in Maputo markets is unlikely to have a significant impact on the conservation of reptiles in Mozambique. However, we suggest that international trade with South Africa is likely having a larger impact, given observations of Mozambican nationals selling a diverse range of fauna in urban traditional medicine markets in Johannesburg and Durban.SP201
A Glimpse Far into the Future: Understanding Long-term Crowd Worker Quality
Microtask crowdsourcing is increasingly critical to the creation of extremely
large datasets. As a result, crowd workers spend weeks or months repeating the
exact same tasks, making it necessary to understand their behavior over these
long periods of time. We utilize three large, longitudinal datasets of nine
million annotations collected from Amazon Mechanical Turk to examine claims
that workers fatigue or satisfice over these long periods, producing lower
quality work. We find that, contrary to these claims, workers are extremely
stable in their quality over the entire period. To understand whether workers
set their quality based on the task's requirements for acceptance, we then
perform an experiment where we vary the required quality for a large
crowdsourcing task. Workers did not adjust their quality based on the
acceptance threshold: workers who were above the threshold continued working at
their usual quality level, and workers below the threshold self-selected
themselves out of the task. Capitalizing on this consistency, we demonstrate
that it is possible to predict workers' long-term quality using just a glimpse
of their quality on the first five tasks.Comment: 10 pages, 11 figures, accepted CSCW 201
Rat interleukin-2-activated natural killer (A-NK) cell-mediated lysis is determined by the presence of CD18 on A-NK cells and the absence of major histocompatibility complex class I on target cells
The precise mechanism by which target cells are recognized and subsequently lysed by interleukin-2-activated natural killer (A-NK) cells is poorly understood. In this study the role of major histocompatibility complex (MHC) class I and adhesion molecules in the recognition and lysis of tumor cells was investigated in a syngeneic Wag rat model. Preincubation of tumor cells with F(ab′)2 fragments of anti-MHC class I monoclonal antibody (mAb) OX18 strongly enhanced the A-NK cell-mediated lysis. Also normal syngeneic cells such as T cells and A-NK cells became highly sensitive for lysis by A-NK cells after preincubation with mAb OX18. Two other mAb against MHC class I had no effect on lysis of target cells. These data indicate that masking of MHC class I on syngeneic tumor and normal cells by mAb OX18 is sufficient for A-NK cells to recognize target cells as non-self, resulting in lysis. In addition, we found that the presence of mAb against the β2 (CD18)-integrins blocked the lysis of all tumor cell lines by A-NK cells in 51Cr-release assays, also when target cells were preincubated with mAb OX18. Because of the absence of CD18 on most tumor cells we concluded that a CD18-associated integrin on A-NK cells is essential for lysis of target cells. These results show that in this syngeneic rat model CD18 on A-NK cells together with MHC class I on tumor cells determine A-NK cell-mediated lysis. Furthermore, we hypothesize that the anti-MHC class I OX18 recognizes an epitope on rat MHC class I which is, or is very close to, the restriction element determining A-NK cell-mediated lysis
Analyses of multiplicity distributions with \eta_c and Bose-Einstein correlations at LHC by means of generalized Glauber-Lachs formula
Using the negative binomial distribution (NBD) and the generalized
Glauber-Lachs (GGL) formula, we analyze the data on charged multiplicity
distributions with pseudo-rapidity cutoffs \eta_c at 0.9, 2.36, and 7 TeV by
ALICE Collaboration and at 0.2, 0.54, and 0.9 TeV by UA5 Collaboration. We
confirm that the KNO scaling holds among the multiplicity distributions with
\eta_c = 0.5 at \sqrt{s} = 0.2\sim2.36 TeV and estimate the energy dependence
of a parameter 1/k in NBD and parameters 1/k and \gamma (the ratio of the
average value of the coherent hadrons to that of the chaotic hadrons) in the
GGL formula. Using empirical formulae for the parameters 1/k and \gamma in the
GGL formula, we predict the multiplicity distributions with \eta_c = 0.5 at 7
and 14 TeV. Data on the 2nd order Bose-Einstein correlations (BEC) at 0.9 TeV
by ALICE Collaboration and 0.9 and 2.36 TeV by CMS Collaboration are also
analyzed based on the GGL formula. Prediction for the 3rd order BEC at 0.9 and
2.36 TeV are presented. Moreover, the information entropy is discussed
Semi-automatic standardized analysis method to objectively evaluate near-infrared fluorescent dyes in image-guided surgery
Significance: Near-infrared fluorescence imaging still lacks a standardized, objective method to evaluate fluorescent dye efficacy in oncological surgical applications. This results in difficulties in translation between preclinical to clinical studies with fluorescent dyes and in the reproduction of results between studies, which in turn hampers further clinical translation of novel fluorescent dyes. Aim: Our aim is to develop and evaluate a semi-automatic standardized method to objectively assess fluorescent signals in resected tissue. Approach: A standardized imaging procedure was designed and quantitative analysis methods were developed to evaluate non-targeted and tumor-targeted fluorescent dyes. The developed analysis methods included manual selection of region of interest (ROI) on white light images, automated fluorescence signal ROI selection, and automatic quantitative image analysis. The proposed analysis method was then compared with a conventional analysis method, where fluorescence signal ROIs were manually selected on fluorescence images. Dice similarity coefficients and intraclass correlation coefficients were calculated to determine the inter- and intraobserver variabilities of the ROI selections and the determined signal- and tumor-to-background ratios. Results: The proposed non-targeted fluorescent dyes analysis method showed statistically significantly improved variabilities after application on indocyanine green specimens. For specimens with the targeted dye SGM-101, the variability of the background ROI selection was statistically significantly improved by implementing the proposed method. Conclusion: Semi-automatic methods for standardized quantitative analysis of fluorescence images were successfully developed and showed promising results to further improve the reproducibility and standardization of clinical studies evaluating fluorescent dyes.</p
Semi-automatic standardized analysis method to objectively evaluate near-infrared fluorescent dyes in image-guided surgery
Significance: Near-infrared fluorescence imaging still lacks a standardized, objective method to evaluate fluorescent dye efficacy in oncological surgical applications. This results in difficulties in translation between preclinical to clinical studies with fluorescent dyes and in the reproduction of results between studies, which in turn hampers further clinical translation of novel fluorescent dyes. Aim: Our aim is to develop and evaluate a semi-automatic standardized method to objectively assess fluorescent signals in resected tissue. Approach: A standardized imaging procedure was designed and quantitative analysis methods were developed to evaluate non-targeted and tumor-targeted fluorescent dyes. The developed analysis methods included manual selection of region of interest (ROI) on white light images, automated fluorescence signal ROI selection, and automatic quantitative image analysis. The proposed analysis method was then compared with a conventional analysis method, where fluorescence signal ROIs were manually selected on fluorescence images. Dice similarity coefficients and intraclass correlation coefficients were calculated to determine the inter- and intraobserver variabilities of the ROI selections and the determined signal- and tumor-to-background ratios. Results: The proposed non-targeted fluorescent dyes analysis method showed statistically significantly improved variabilities after application on indocyanine green specimens. For specimens with the targeted dye SGM-101, the variability of the background ROI selection was statistically significantly improved by implementing the proposed method. Conclusion: Semi-automatic methods for standardized quantitative analysis of fluorescence images were successfully developed and showed promising results to further improve the reproducibility and standardization of clinical studies evaluating fluorescent dyes.</p
Multiplicity Studies and Effective Energy in ALICE at the LHC
In this work we explore the possibility to perform ``effective energy''
studies in very high energy collisions at the CERN Large Hadron Collider (LHC).
In particular, we focus on the possibility to measure in collisions the
average charged multiplicity as a function of the effective energy with the
ALICE experiment, using its capability to measure the energy of the leading
baryons with the Zero Degree Calorimeters. Analyses of this kind have been done
at lower centre--of--mass energies and have shown that, once the appropriate
kinematic variables are chosen, particle production is characterized by
universal properties: no matter the nature of the interacting particles, the
final states have identical features. Assuming that this universality picture
can be extended to {\it ion--ion} collisions, as suggested by recent results
from RHIC experiments, a novel approach based on the scaling hypothesis for
limiting fragmentation has been used to derive the expected charged event
multiplicity in interactions at LHC. This leads to scenarios where the
multiplicity is significantly lower compared to most of the predictions from
the models currently used to describe high energy collisions. A mean
charged multiplicity of about 1000-2000 per rapidity unit (at ) is
expected for the most central collisions at .Comment: 12 pages, 19 figures. In memory of A. Smirnitski
The spatio-temporal pattern of Argentine shortfin squid (Illex argentinus) abundance in the Spanish bottom-trawl fishery in the southwest Atlantic.
The Argentine shortfin squid (Illex argentinus) is a common neritic species occurring in waters off Brazil, Uruguay, Argentina, and the Falkland/Malvinas Islands in the southwest
Atlantic. Illex is the most important cephalopod species in the area and plays a significant role in the ecosystem. It is object of major fisheries using both trawlers (mostly from European countries) and jigging vessels (mainly from Asian countries) and the actual total annual catch could reach up to 700 thousand tons. Fishery and biological information collected by scientific observers aboard commercial trawlers between 1988 and 2003 was analysed in relation to physical and environmental factors to establish the spatio-temporal pattern of the species distribution. The data included 26 168 fishing haul records, of which 11103 were positive. CPUE (Catch Per Unit Effort, kg⋅hr-1) was used as abundance index. The analyses of the general spatio-temporal pattern of fish abundance, and the influence of environmental factors, such as SST, SBT and depth on squid abundance and distribution, was based on correlation, variograms, and time-series maps created using GIS. The areas of the highest densities were found in deep waters of the High Seas between 44.5º S – 47.0º S outside the Argentinean EEZ and to the north-west of the Islands in February–May. The correlations between squid abundance and cloud index at different moon phases were also analyzed
Observational diagnostics of gas in protoplanetary disks
Protoplanetary disks are composed primarily of gas (99% of the mass).
Nevertheless, relatively few observational constraints exist for the gas in
disks. In this review, I discuss several observational diagnostics in the UV,
optical, near-IR, mid-IR, and (sub)-mm wavelengths that have been employed to
study the gas in the disks of young stellar objects. I concentrate in
diagnostics that probe the inner 20 AU of the disk, the region where planets
are expected to form. I discuss the potential and limitations of each gas
tracer and present prospects for future research.Comment: Review written for the proceedings of the conference "Origin and
Evolution of Planets 2008", Ascona, Switzerland, June 29 - July 4, 2008. Date
manuscript: October 2008. 17 Pages, 6 graphics, 134 reference
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