Turbulent drag on a low-frequency vibrating grid in superfluid He-4 at very low temperatures

We present measurements of the dissipative turbulent drag on a vibrating grid in superfluid He-4 over a wide range of (low) frequencies. At high velocities, the dissipative drag is independent of frequency and is approximately the same as that measured in normal liquid He-4. We present measurements on a similar grid in superfluid He-3-B at low temperatures which shows an almost identical turbulent drag coefficient at low frequencies. However, the turbulent drag in He-3-B is substantially higher at higher frequencies. We also present measurements of the inertial drag coefficient for grid turbulence in He-4. The inertial drag coefficient is significantly reduced by turbulence in both superfluid and normal liquid He-4

Experimental nonlocal and surreal Bohmian trajectories

Weak measurement allows one to empirically determine a set of average trajectories for an ensemble of quantum particles. However, when two particles are entangled, the trajectories of the first particle can depend nonlocally on the position of the second particle. Moreover, the theory describing these trajectories, called Bohmian mechanics, predicts trajectories that were at first deemed “surreal” when the second particle is used to probe the position of the first particle. We entangle two photons and determine a set of Bohmian trajectories for one of them using weak measurements and postselection. We show that the trajectories seem surreal only if one ignores their manifest nonlocality.Full Tex

What Predicts Hospital Admissions in Community-Dwelling People With Parkinsonism?

Objectives: Previous studies have looked at the reasons for hospital admission in people with parkinsonism (PwP), yet few have looked at factors that precipitate admission. Methods: People with parkinsonism with a diagnosis of idiopathic Parkinson disease of Hoehn and Yahr stage III-V and those with Parkinson plus syndromes were assessed for motor and nonmotor symptoms, quality of life, and functional performance. Logistic regression was used to investigate predictors of hospital admission over the subsequent 2 years. Results: Overall, 162 patients consented to be part of the study. Seventy-one PwP (43.8%) had at least 1 hospital admission, and 17 (10.5%) patients had 3 or more admissions to hospital. Poorer cognition, more nonmotor symptoms, poorer quality of life, slower timed-up-and-go test scores, and abnormal swallow predicted a subsequent hospital admission. Discussion: Our study emphasizes the importance of nonmotor symptoms in predicting admission. A cost–benefit analysis of early intervention to prevent admission should be considered

Deficiency of the zinc finger protein ZFP106 causes motor and sensory neurodegeneration

Acknowledgements We are indebted to Jim Humphries, JennyCorrigan, LizDarley, Elizabeth Joynson, Natalie Walters, Sara Wells and the whole necropsy, histology, genotyping and MLC ward 6 teams at MRC Harwell for excellent technical assistance. We thank the staff of the WTSI Illumina Bespoke Team for the RNA-seq data, the Sanger Mouse Genetics Project for the initial mouse characterization and Dr David Adams for critical reading of the manuscript. We also thank KOMP for the mouse embryonic stem cells carrying the knockout first promoter-less allele (tm1a(KOMP)Wtsi) within Zfp016. Conflict of Interest statement. None declared. Funding This work was funded by the UK Medical Research Council (MRC) to A.A.-A. and a Motor Neurone Disease Association (MNDA) project grant to A.A.-A. and EMCF. D.L.H.B. is a Wellcome Trust Senior Clinical Scientist Fellow and P.F. is a MRC/MNDA Lady Edith Wolfson Clinician Scientist Fellow. Funding to pay the Open Access publication charges for this article was provided by the MRC grant number: MC_UP_A390_1106.Peer reviewedPublisher PD

Incorporating prior knowledge improves detection of differences in bacterial growth rate

BACKGROUND: Robust statistical detection of differences in the bacterial growth rate can be challenging, particularly when dealing with small differences or noisy data. The Bayesian approach provides a consistent framework for inferring model parameters and comparing hypotheses. The method captures the full uncertainty of parameter values, whilst making effective use of prior knowledge about a given system to improve estimation. RESULTS: We demonstrated the application of Bayesian analysis to bacterial growth curve comparison. Following extensive testing of the method, the analysis was applied to the large dataset of bacterial responses which are freely available at the web-resource, ComBase. Detection was found to be improved by using prior knowledge from clusters of previously analysed experimental results at similar environmental conditions. A comparison was also made to a more traditional statistical testing method, the F-test, and Bayesian analysis was found to perform more conclusively and to be capable of attributing significance to more subtle differences in growth rate. CONCLUSIONS: We have demonstrated that by making use of existing experimental knowledge, it is possible to significantly improve detection of differences in bacterial growth rate

Increased levels of macrophage inflammatory proteins result in resistance to R5-tropic HIV-1 in a subset of elite controllers

Elite controllers (ECs) are a rare group of HIV seropositive individuals who are able to control viral replication without antiretroviral therapy. The mechanisms responsible for this phenotype, however, have not been fully elucidated. In this study, we examined CD4+ T cell resistance to HIV in a cohort of elite controllers and explored transcriptional signatures associated with cellular resistance. We demonstrate that a subgroup of elite controllers possess CD4+ T cells that are specifically resistant to R5-tropic HIV while remaining fully susceptible to X4-tropic and vesicular stomatitis virus G (VSV-G)-pseudotyped viruses. Transcriptome analysis revealed 17 genes that were differentially regulated in resistant elite controllers relative to healthy controls. Notably, the genes encoding macrophage inflammatory protein 1α (MIP-1α), CCL3 and CCL3L1, were found to be upregulated. The MIP-1α, MIP-1β, and RANTES chemokines are natural ligands of CCR5 and are known to interfere with HIV replication. For three elite controllers, we observed increased production of MIP-1α and/or MIP-1β at the protein level. The supernatant from resistant EC cells contained MIP-1α and MIP-1β and was sufficient to confer R5-tropic resistance to susceptible CD4+ T cells. Additionally, this effect was reversed by using inhibitory anti-MIP antibodies. These results suggest that the T cells of these particular elite controllers may be naturally resistant to HIV infection by blocking R5-tropic viral entr

Effect of a Brief Video Intervention on Incident Infection among Patients Attending Sexually Transmitted Disease Clinics

In a controlled trial at three urban STD clinics, Lee Warner and colleagues find that showing an educational video in waiting rooms reduced new infections by approximately 10%

Structure of Escherichia coli AdhP (ethanol-inducible dehydrogenase) with bound NAD

The crystal structure of AdhP, a recombinantly expressed alcohol dehydrogenase from Escherichia coli K-12 (substrain MG1655), was determined to 2.01 angstroms resolution. The structure, which was solved using molecular replacement, also included the structural and catalytic zinc ions and the cofactor nicotinamide adenine dinucleotide (NAD). The crystals belonged to space group P21, with unit-cell parameters a = 68.18, b = 118.92, c = 97.87 angstroms, beta = 106.41 degrees. The final R-factor and R-free were 0.138 and 0.184, respectively. The structure of the active site of AdhP suggested a number of residues that may participate in a proton relay, and the overall structure of AdhP, including the coordination to structural and active-site zinc ions, is similar to those of other tetrameric alcohol dehydrogenase enzymes.YesThe manuscript was peer-reviewed by two anonymous reviewers