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International audience; We develop and characterize a wide angle static and dynamic light scattering under shear setup. The apparatus is suitable for the study of the structure and the dynamics of soft materials systems with sub-micron characteristic length scale. The shear device consists in two parallel plates and the optical setup allows to perform light scattering measurements in any plane that contains the gradient of the velocity field direction. We demonstrate several capabilities of our apparatus : a measurement of the evolution with shear of the first peak of the structure factor of a concentrated suspension of spherical particles, both in the compression and the extension quadrants of the shear flow, and the measurement of the velocity profile in dynamic light scattering. We present a theoretical treatment of light scattering under flow that takes into account the Gaussian character of the illumination and of the detection optical paths, in the case where the scattering volume extension is smaller than the gap of the flow cell, and compare with experimental measurements.

Electrically manipulating the quantum properties of nano-objects, such as atoms or molecules, is typically done using scanning tunnelling microscopes 1-7 and lateral junctions 8-13. The resulting nanotransport path is well established in these model devices. Societal applications require transposing this knowledge to nano-objects embedded within vertical solid-state junctions, which can advantageously harness spintronics 14 to address these quantum properties thanks to ferromagnetic electrodes and high-quality interfaces 15-17. The challenge here is to ascertain the device's effective, buried nanotransport path 18 , and to electrically involve these nano-objects in this path by shrinking the device area from the macro-17,19-22 to the nano-scale 23-25 while maintaining high structural/chemical quality across the heterostructure. We've developed a low-tech, resist-and solvent-free technological process that can craft nanopillar devices from entire in-situ grown heterostructures, and use it to study magnetotransport between two Fe and Co ferromagnetic electrodes across a functional magnetic CoPc molecular layer 26,27. We observe how spin-flip transport across CoPc molecular spin chains promotes a specific magnetoresistance effect, and alters the nanojunction's magnetism through spintronic anisotropy 28. In the process, we identify three magnetic units along the effective nanotransport path thanks to a macrospin model of magnetotransport. Our work elegantly connects the until now loosely associated concepts of spin-flip spectroscopy 2,3 , magnetic exchange bias 29,30 and magnetotransport 24,25 due to molecular spin chains, within a solid-state device. We notably measure a 5.9meV energy threshold for magnetic decoupling between the Fe layer's buried atoms and those in contact with the CoPc layer forming the so-called 'spinterface' 16. This provides a first insight into the experimental energetics of this promising low-power information encoding unit 31.

Polyclonal antibodies including purified antibody fractions and animal or human antisera may react with unknown antigens or antigens other than their main specificity in reactions that are best visualized by gel electroimmunoprecipitation methods (e.g., when analyzing complex antigen mixtures). The great advantage of gel immunoprecipitation approaches is that each immunoprecipitate contains antigen in a pure form and that the precipitate is separated by position, shape, and size from other precipitates in the complex patterns of crossed immunoelectrophoresis. The identification of the antigen content of such immunoprecipitates is important but challenging because of the very stable, high-affinity complex formation leading to precipitation in the gels. Here, we present detailed step-by-step recipes for identifying the antigen content of electroimmunoprecipitates.

Background The HPTN 071 (PopART) cluster-randomised trial provided door-to-door HIV testing services to a large proportion of individuals residing in 21 intervention communities in Zambia and South Africa from 2014 to 2017 and reached the UNAIDS first 90 target among women in Zambia, yet gaps remained among men and young adults. This cluster-randomised study nested in the HPTN 071 (PopART) trial sought to increase knowledge of HIV status across all groups by offering the choice of oral HIV self-testing in addition to routine door-to-door HIV testing services. Methods We nested this cluster-randomised trial in four HTPN 071 (PopART) intervention communities in northern Zambia. 66 zones (clusters) in these communities were randomly allocated (1:1) to either oral HIV self-testing plus routine door-to-door HIV testing services (HIV self-testing group) or the PopART standard of care of door-to-door HIV testing services alone (non- HIV self-testing group) over a 3-month period. All individuals aged 16 years or older were eligible for HIV testing. Randomisation was achieved by randomly selecting one allocation from a list of 10 000 possible allocations during a public ceremony. In HIV self-testing zones, trained lay-counsellors (known as community HIV care providers) visited households and offered eligible individuals the choice of HIV testing using HIV self-testing or routine door-to-door HIV testing services. For individuals aged 18 years or older whose partner was absent during the household visit, an HIV self-test kit could be left for secondary distribution to the absent partner. The primary outcome was knowledge of HIV status (defined as self-reporting HIV positive to the community HIV care providers or accepting an offer of HIV testing services). Outcomes were measured among households that were first visited, and individuals first enumerated as a household member during the HIV self-testing intervention period. We analysed data at the individual level using population-average logistic regression models, accounting for clustering of outcomes by zone, to estimate the effect of the intervention. This trial is registered with ClinicalTrials.gov, number NCT02994329. Findings Between Feb 1, and April 30, 2017, the community HIV care providers enumerated 13 267 eligible individuals in the HIV self-testing group and 13 706 in the non-HIV self-testing group. After intervention implementation, 9027 (68%) of 13 267 in the HIV self-testing group had knowledge of HIV status compared with 8952 (65%) of 13 706 in the non-HIV self-testing group (adjusted odds ratio 1·30, 95% CI 1·03–1·65; p=0·03). The effect differed by sex (pinteraction=0·01). Among men, knowledge of HIV status was higher in the HIV self-testing group than in the non-HIV self-testing group (3843 [60%] of 6368 vs 3571 [55%] of 6486; adjusted odds ratio 1·31, 95% CI 1·07–1·60; p=0·01). There was no evidence of a between-group difference among female participants. Interpretation Providing a choice of HIV self-testing during delivery of door-to-door HIV testing services increased knowledge of HIV status, driven by an effect among men. Lay counsellors have a vital role to play in adapting HIV self-testing interventions to local context.

Objective: To investigate the reliability and agreement of measures of lower extremity muscle strength, power and functional performance in patients with hip osteoarthritis at different time intervals, and to compare these with the same measures in healthy peers. Design: Intra-rater test-retest separated by 1, 2, or 2.5 weeks in patients, and 1 week in healthy peers. Subjects: Patients with hip osteoarthritis (age range 61–83 years) with 1 (n = 37), 2 (n = 35), or 2.5 weeks (n = 15) between tests, and 35 healthy peers (age range 63–82 years). Methods: Maximal isometric hip and thigh strength, leg extensor power, and functional performance (8-foot up&go, stair climbing, chair stand and 6-min walk) were measured in patients, and quadriceps strength, leg extensor power and functional performance were measured in healthy peers. Systematic error, reliability and agreement were calculated. Results: Most hip strength measurements for the most symptomatic extremity, and nearly all strength measurements for the least symptomatic lower extremity, declined after 1 week (p < 0.05), but not after a 2.5-week interval. In healthy peers, quadriceps strength was unchanged. Regardless of the time interval, leg extensor power was unchanged, while functional performances improved at retest for all participants. Conclusion: In patients with hip osteoarthritis leg extensor power is unaffected by the time interval between tests, in contrast to muscle strength and functional performance.

The aim of this work is to develop an algorithm based on causal entropic forces that induces swarming behavior. By using the concept of entropy we pursue a completely new approach to swarming. After discussing the significance of entropy and swarming in the context of complex systems we will approach the theoretical and methodological fundamentals of the work. The influence of the key parameters is examined to find a combination that creates swarm behavior.

PURPOSE: Our study identified factors common to a variety of populations and settings that may promote or inhibit uptake and adherence to falls-related interventions. DESIGN AND METHODS: Semistructured interviews to assess perceived advantages and barriers to taking part in falls-related interventions were carried out in six European countries with 69 people aged 68 to 97 years. The sample was selected to include people with very different experiences of participation or nonparticipation in falls-related interventions, but all individuals were asked about interventions that included strength and balance training. RESULTS: Attitudes were similar in all countries and contexts. People were motivated to participate in strength and balance training by a wide range of perceived benefits (interest and enjoyment, improved health, mood, and independence) and not just reduction of falling risk. Participation also was encouraged by a personal invitation from a health practitioner and social approval from family and friends. Barriers to participation included denial of falling risk, the belief that no additional falls-prevention measures were necessary, practical barriers to attendance at groups (e.g., transport, effort, and cost), and a dislike of group activities. IMPLICATIONS: Because many older people reject the idea that they are at risk of falling, the uptake of strength and balance training programs may be promoted more effectively by maximizing and emphasizing their multiple positive benefits for health and well-being. A personal invitation from a health professional to participate is important, and it also may be helpful to provide home-based programs for those who dislike or find it difficult to attend groups. Language: en

The California Verbal Learning Test (CVLT) is recognized as a standard clinical tool for assessing episodic memory difficulties in multiple sclerosis (MS), but its neural correlates have not yet been examined in detail in this patient population. We combined neuropsychological examination and diffusion tensor imaging (DTI) analysis in a group of MS patients (N = 50) and demographically matched healthy participants (N = 20). We investigated the degree of impairment of the uncinate fascicle (UF), the superior longitudinal fascicle (SLF), the fornix (FX) and the cingulum (CG). The patients were impaired on all CVLT parameters and the DTI parameters correlated moderately with disease-related variables. Regression analyses in the complete study sample showed that CVLT learning scores correlated with impairment of the right UF. This association reached marginal significance in the patient sample. In contrast to other studies claiming retrieval deficits, our results suggest that encoding and consolidation deficits may play a major role in verbal memory impairments in MS. The findings also provide evidence for an association between degree of myelination of prefrontal fibre pathways and encoding efficiency. Finally, DTI-derived measurements appear to reflect disease progression in MS. The results are discussed in light of functional MRI studies investigating compensatory brain activity during cognitive processing in MS.