743 research outputs found
Color Capable Sub-Pixel Resolving Optofluidic Microscope and Its Application to Blood Cell Imaging for Malaria Diagnosis
Miniaturization of imaging systems can significantly benefit clinical diagnosis in challenging environments, where access to physicians and good equipment can be limited. Sub-pixel resolving optofluidic microscope (SROFM) offers high-resolution imaging in the form of an on-chip device, with the combination of microfluidics and inexpensive CMOS image sensors. In this work, we report on the implementation of color SROFM prototypes with a demonstrated optical resolution of 0.66 µm at their highest acuity. We applied the prototypes to perform color imaging of red blood cells (RBCs) infected with Plasmodium falciparum, a particularly harmful type of malaria parasites and one of the major causes of death in the developing world
Local Charge of the nu=5/2 Fractional Quantum Hall State
Electrons in two dimensions and strong magnetic fields effectively lose their
kinetic energy and display exotic behavior dominated by Coulomb forces. When
the ratio of electrons to magnetic flux quanta in the system is near 5/2, the
unique correlated phase that emerges is predicted to be gapped with
fractionally charged quasiparticles and a ground state degeneracy that grows
exponentially as these quasiparticles are introduced. Interestingly, the only
way to transform between the many ground states would be to braid the
fractional excitations around each other, a property with applications in
quantum information processing. Here we present the first observation of
localized quasiparticles at nu=5/2, confined to puddles by disorder. Using a
local electrometer to compare how quasiparticles at nu=5/2 and nu=7/3 charge
these puddles, we are able to extract the ratio of local charges for these
states. Averaged over several disorder configurations and samples, we find the
ratio to be 4/3, suggesting that the local charges are e/3 at seven thirds and
e/4 at five halves, in agreement with theoretical predictions. This
confirmation of localized e/4 quasiparticles is necessary for proposed
interferometry experiments to test statistics and computational ability of the
state at nu=5/2.Comment: 6 pages, 4 figures corrected titl
Screening and breeding for insect resistance in pea, lentil, faba bean and chickpea
Although grain legumes are considered to be particularly susceptible to
insect damage, few studies have quantified these losses in farmers’ fields.
Insecticides can protect each of the; legumes from pest damage, but plant
resistance appears to be an attractive alternative, particularly for developing
countries. Large differences in susceptibility to the major insect pests have
been detected in the germplasm of each of pea, faba bean, lentil and
chickpea, but there are no reports of successful exploitation of genotypes
bred for resistance. Methods of screening and breeding for resistance are
described, with particular reference to Heliothis armigera on chickpea. The
dangers of breeding crops under protected conditions, for subsequent use in
farmers’ fields where protection is not afforded, are emphasized
Quasi-Particle Tunneling in Anti-Pfaffian Quantum Hall State
We study tunneling phenomena at the edge of the anti-Pfaffian quantum Hall
state at the filling factor . The edge current in a single
point-contact is considered. We focus on nonlinear behavior of two-terminal
conductance with the increase in negative split-gate voltage. Expecting the
appearance of the intermediate conductance plateau we calculate the value of
its conductance by using the renormalization group (RG) analysis. Further, we
show that non-perturbative quasi-particle tunneling is effectively described as
perturbative electron tunneling by the instanton method. The two-terminals
conductance is written as a function of the gate voltage. The obtained results
enable us to distinguish the anti-Pfaffian state from the Pfaffian state
experimentally.Comment: 5 pages, 4 figure
The role of the cytoskeleton in capacitaftive calcium entry in myenteric glia
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73680/1/j.1365-2982.2003.00406.x.pd
Social interaction, noise and antibiotic-mediated switches in the intestinal microbiota
The intestinal microbiota plays important roles in digestion and resistance
against entero-pathogens. As with other ecosystems, its species composition is
resilient against small disturbances but strong perturbations such as
antibiotics can affect the consortium dramatically. Antibiotic cessation does
not necessarily restore pre-treatment conditions and disturbed microbiota are
often susceptible to pathogen invasion. Here we propose a mathematical model to
explain how antibiotic-mediated switches in the microbiota composition can
result from simple social interactions between antibiotic-tolerant and
antibiotic-sensitive bacterial groups. We build a two-species (e.g. two
functional-groups) model and identify regions of domination by
antibiotic-sensitive or antibiotic-tolerant bacteria, as well as a region of
multistability where domination by either group is possible. Using a new
framework that we derived from statistical physics, we calculate the duration
of each microbiota composition state. This is shown to depend on the balance
between random fluctuations in the bacterial densities and the strength of
microbial interactions. The singular value decomposition of recent metagenomic
data confirms our assumption of grouping microbes as antibiotic-tolerant or
antibiotic-sensitive in response to a single antibiotic. Our methodology can be
extended to multiple bacterial groups and thus it provides an ecological
formalism to help interpret the present surge in microbiome data.Comment: 20 pages, 5 figures accepted for publication in Plos Comp Bio.
Supplementary video and information availabl
Pretreatment Vitamin D Concentrations Do Not Predict Therapeutic Outcome to Anti-TNF Therapies in Biologic-Naïve Patients With Active Luminal Crohn's Disease
This is final version. Available on open access from Oxford University Press via the DOI in this recordData Availability:
Individual participant deidentified data that underlie the results reported in this article will be available immediately after publication for a period of 5 years. The data will be made available to investigators whose proposed use of the data has been approved by an independent review committee. Analyses will be restricted to the aims in the approved proposal. Proposals should be directed to [email protected]. To gain access, data requestors will need to sign a data access agreement.BACKGROUND AND AIMS: Vitamin D has a regulatory role in innate and adaptive immune processes. Previous studies have reported that low pretreatment vitamin D concentrations are associated with primary non-response (PNR) and non-remission to anti-TNF therapy. This study aimed to assess whether pretreatment 25-hydroxyvitamin D concentrations predicted PNR and non-remission to infliximab and adalimumab in patients with active luminal Crohn's disease. METHODS: 25-Hydroxyvitamin D concentrations were measured in stored baseline samples from 659 infliximab- and 448 adalimumab-treated patients in the Personalised Anti-TNF Therapy in Crohn's disease (PANTS) study. Cut-offs for vitamin D were deficiency 50 nmol/L. RESULTS: About 17.1% (189/1107; 95% CI, 15.0-19.4) and 47.7% (528/1107; 95% CI, 44.8-50.6) of patients had vitamin D deficiency and insufficiency, respectively. 22.2% (246/1107) of patients were receiving vitamin D supplementation. Multivariable analysis confirmed that sampling during non-summer months, South Asian ethnicity, lower serum albumin concentrations, and non-treatment with vitamin D supplementation were independently associated with lower vitamin D concentrations. Pretreatment vitamin D status did not predict response or remission to anti-TNF therapy at week 14 (infliximab Ppnr = .89, adalimumab Ppnr = .18) or non-remission at week 54 (infliximab P = .13, adalimumab P = .58). Vitamin D deficiency was, however, associated with a longer time to immunogenicity in patients treated with infliximab, but not adalimumab. CONCLUSIONS: Vitamin D deficiency is common in patients with active Crohn's disease. Unlike previous studies, pretreatment vitamin D concentration did not predict PNR to anti-TNF treatment at week 14 or nonremission at week 54.National Institute for Health and Care Research (NIHR)CORECrohn's & Colitis UKC3AbbVieMerck Sharp & DohmeNAPP PharmaceuticalsPfizerCelltrion HealthcareEuropean Crohn’s Colitis Organisation (ECCO)European Society of Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN
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