150 research outputs found
Residence time estimates for asymmetric simple exclusion dynamics on stripes
The target of our study is to approximate numerically and, in some particular
physically relevant cases, also analytically, the residence time of particles
undergoing an asymmetric simple exclusion dynamics on a stripe. The source of
asymmetry is twofold: (i) the choice of boundary conditions (different
reservoir levels) and (ii) the strong anisotropy from a nonlinear drift with
prescribed directionality. We focus on the effect of the choice of anisotropy
in the flux on the asymptotic behavior of the residence time with respect to
the length of the stripe. The topic is relevant for situations occurring in
pedestrian flows or biological transport in crowded environments, where lateral
displacements of the particles occur predominantly affecting therefore in an
essentially way the efficiency of the overall transport mechanism
Biliary atresia with hyaline cartilage at the porta hepatis: a novel finding of undetermined significance: a case report
Biliary atresia is an important cause of liver disease and morbidity in infants with unknown etiology. To date, only five cases of biliary atresia with hyaline cartilage at the porta hepatis have been described. We present the case of a 65-day-old male child, with further insight and detailed discussion of this heterotopia of undetermined significance.Keywords: biliary atresia, hyaline cartilage, liver diseas
Stem cell transplantation of children with Acute Leukemia
This article does not have an abstract
The High Time Resolution Universe Pulsar Survey -- XVIII. The reprocessing of the HTRU-S Low Lat survey around the Galactic centre using a Fast Folding Algorithm pipeline for accelerated pulsars
The HTRU-S Low Latitude survey data within 1of the Galactic Centre
(GC) were searched for pulsars using the Fast Folding Algorithm (FFA). Unlike
traditional Fast Fourier Transform (FFT) pipelines, the FFA optimally folds the
data for all possible periods over a given range, which is particularly
advantageous for pulsars with low-duty cycle. For the first time, a search over
acceleration was included in the FFA to improve its sensitivity to binary
pulsars. The steps in dispersion measure (DM) and acceleration were optimised,
resulting in a reduction of the number of trials by 86 per cent. This was
achieved over a search period range from 0.6-s to 432-s, i.e. 10 per cent of
the observation time (4320s), with a maximum DM of 4000 pc cm and an
acceleration range of m s. The search resulted in the
re-detections of four known pulsars, including a pulsar which was missed in
previous FFT processing of this survey. This result indicates that the FFA
pipeline is more sensitive than the FFT pipeline used in the previous
processing of the survey within our parameter range. Additionally, we
discovered a 1.89-s pulsar, PSR J1746-2829, with a large DM, located~0.5 from
the GC. Follow-up observations revealed that this pulsar has a relatively flat
spectrum() and has a period derivative of
s s, implying a surface magnetic field of
G and a characteristic age of yr. While the
period, spectral index, and surface magnetic field strength are similar to many
radio magnetars, other characteristics such as high linear polarization are
absent.Comment: 12 pages, 6 figures, 4 tables, Accepted for publication on Monthly
Notices of the Royal Astronomical Societ
The International Collaboration for Research methods Development in Oncology (CReDO) workshops: shaping the future of global oncology research
Low-income and middle-income countries (LMICs) have a disproportionately high burden of cancer and cancer mortality. The unique barriers to optimum cancer care in these regions necessitate context-specific research. The conduct of research in LMICs has several challenges, not least of which is a paucity of formal training in research methods. Building capacity by training early career researchers is essential to improve research output and cancer outcomes in LMICs. The International Collaboration for Research methods Development in Oncology (CReDO) workshop is an initiative by the Tata Memorial Centre and the National Cancer Grid of India to address gaps in research training and increase capacity in oncology research. Since 2015, there have been five CReDO workshops, which have trained more than 250 oncologists from India and other countries in clinical research methods and protocol development. Participants from all oncology and allied fields were represented at these workshops. Protocols developed included clinical trials, comparative effectiveness studies, health services research, and observational studies, and many of these protocols were particularly relevant to cancer management in LMICs. A follow-up of these participants in 2020 elicited an 88% response rate and showed that 42% of participants had made progress with their CReDO protocols, and 73% had initiated other research protocols and published papers. In this Policy Review, we describe the challenges to research in LMICs, as well as the evolution, structure, and impact of CReDO and other similar workshops on global oncology research
UEV-1 Is an Ubiquitin-Conjugating Enzyme Variant That Regulates Glutamate Receptor Trafficking in C. elegans Neurons
The regulation of AMPA-type glutamate receptor (AMPAR) membrane trafficking is a key mechanism by which neurons regulate synaptic strength and plasticity. AMPAR trafficking is modulated through a combination of receptor phosphorylation, ubiquitination, endocytosis, and recycling, yet the factors that mediate these processes are just beginning to be uncovered. Here we identify the ubiquitin-conjugating enzyme variant UEV-1 as a regulator of AMPAR trafficking in vivo. We identified mutations in uev-1 in a genetic screen for mutants with altered trafficking of the AMPAR subunit GLR-1 in C. elegans interneurons. Loss of uev-1 activity results in the accumulation of GLR-1 in elongated accretions in neuron cell bodies and along the ventral cord neurites. Mutants also have a corresponding behavioral defect—a decrease in spontaneous reversals in locomotion—consistent with diminished GLR-1 function. The localization of other synaptic proteins in uev-1-mutant interneurons appears normal, indicating that the GLR-1 trafficking defects are not due to gross deficiencies in synapse formation or overall protein trafficking. We provide evidence that GLR-1 accumulates at RAB-10-containing endosomes in uev-1 mutants, and that receptors arrive at these endosomes independent of clathrin-mediated endocytosis. UEV-1 homologs in other species bind to the ubiquitin-conjugating enzyme Ubc13 to create K63-linked polyubiquitin chains on substrate proteins. We find that whereas UEV-1 can interact with C. elegans UBC-13, global levels of K63-linked ubiquitination throughout nematodes appear to be unaffected in uev-1 mutants, even though UEV-1 is broadly expressed in most tissues. Nevertheless, ubc-13 mutants are similar in phenotype to uev-1 mutants, suggesting that the two proteins do work together to regulate GLR-1 trafficking. Our results suggest that UEV-1 could regulate a small subset of K63-linked ubiquitination events in nematodes, at least one of which is critical in regulating GLR-1 trafficking
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