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The suppression of ferroquadrupolar order in TmVO4 in a magnetic field is well-described by the transverse field Ising model, enabling detailed studies of critical dynamics near the quantum phase transition. We describe nuclear magnetic resonance measurements in pure and Y-doped single crystals. The non-Kramers nature of the ground state doublet leads to a unique form of the hyperfine coupling that exclusively probes the transverse field susceptibility. Our results show that this quantity diverges at the critical field, in contrast to the mean-field prediction. Furthermore, we find evidence for quantum critical fluctuations present near Tm-rich regions in Y-doped crystals at levels beyond which long-range order is suppressed, suggesting the presence of quantum Griffiths phases.

Abstract Background There is uncertainty about overdiagnosis in mammography screening. Methods We aimed to estimate the effect of screening on breast cancer incidence and overdiagnosis in the NHS Breast Screening Programme in England. The study included 57,493 cases and 105,653 controls, with cases defined as women diagnosed at ages 47–89 with primary breast cancer, invasive or ductal carcinoma in situ, in 2010 or 2011. Where possible, two controls were selected per case, matched on date of birth and screening area. Conditional logistic regression was used to estimate the effect of screening on breast cancer risk, with adjustment for potential self‐selection bias. Results were combined with national incidence data to estimate absolute rates of overdiagnosis. Overdiagnosis was calculated as the cumulative excess of cancers diagnosed in the age group 50–77 in a woman attending three‐yearly screening between ages 50 and 70 compared with a woman attending no screens. Results The estimated number of cases overdiagnosed in women attending all screens in the programme was 679.3 per 100,000 without adjustment for self‐selection bias and 261.2 per 100,000 with adjustment. These corresponded to an estimated 9.5% of screen‐detected cancers overdiagnosed without adjustment and 3.7% with adjustment for self‐selection. Conclusions The NHS Breast Screening Programme in England confers at worst modest levels of overdiagnosis.

Abstract TmVO4 exhibits ferroquadrupolar order of the Tm 4f electronic orbitals at low temperatures, and is a model system for Ising nematicity. A magnetic field oriented along the c-axis constitutes a transverse effective field for the quadrupolar order parameter, continuously tuning the system to a quantum phase transition as the field is increased from zero. In contrast, in-plane magnetic fields couple to the order parameter only at second order, such that orienting along the primary axes of the quadrupole order results in an effective longitudinal field, whereas orienting at 45 degrees results in a second effective transverse field. Not only do in-plane fields engender a marked in-plane anisotropy of the critical magnetic and quadrupole fluctuations above the ferroquadrupolar ordering temperature, but in-plane transverse fields initially enhance the ferroquadrupolar order, before eventually suppressing it, an effect that we attribute to admixing of the higher crystalline electric field levels.

Abstract We report the evolution of nematic fluctuations in FeSe1−x S x single crystals as a function of Sulfur content x across the nematic quantum critical point (QCP) x c ~ 0.17 via Raman scattering. The Raman spectra in the B 1g nematic channel consist of two components, but only the low energy one displays clear fingerprints of critical behavior and is attributed to itinerant carriers. Curie–Weiss analysis of the associated nematic susceptibility indicates a substantial effect of nemato-elastic coupling, which shifts the location of the nematic QCP. We argue that this lattice-induced shift likely explains the absence of any enhancement of the superconducting transition temperature at the QCP. The presence of two components in the nematic fluctuations spectrum is attributed to the dual aspect of electronic degrees of freedom in Hund’s metals, with both itinerant carriers and local moments contributing to the nematic susceptibility.

Abstract Background Improving capacities of health systems to quickly respond to emerging health issues, requires a health information system (HIS) that facilitates evidence‐informed decision‐making at the operational level. In many sub‐Saharan African countries, HIS are mostly designed to feed decision‐making purposes at the central level with limited feedback and capabilities to take action from data at the operational level. This article presents the case of an eHealth innovation designed to capacitate health district management teams (HDMTs) through participatory evidence production and peer‐to‐peer exchange. Methods We used an action research design to develop the eHealth initiative called “District.Team,” a web‐based and facilitated platform targeting HDMTs that was tested in Benin and Guinea from January 2016 to September 2017. On District.Team, rounds of knowledge sharing processes were organized into cycles of five steps. Quantitative and qualitative data were collected to assess the participation of HDMTs and identify enablers and barriers of using District.Team. Results Participation of HDMTs in District.Team varied between cycles and steps. In Benin, 79% to 94% of HDMTs filled in the online questionnaire per cycle compared to 61% to 100% in Guinea per cycle. In Benin, 26% to 41% of HDMTs shared a commentary on the results published on the platform while 21% to 47% participated in the online discussion forum. In Guinea, only 3% to 8% of HDMTs shared a commentary on the results published on the platform while 8% to 74% participated in the online discussion forum. Five groups of factors affected the participation: characteristics of the digital tools, the quality of the facilitation, profile of participants, shared content and data, and finally support from health authorities. Conclusion District.Team has shown that knowledge management platforms and processes valuing horizontal knowledge sharing among peers at the decentralized level of health systems are feasible in limited resource settings.

Adiabatic decompression of paraquadrupolar materials has significant potential as a cryogenic cooling technology. We focus on TmVO4, an archetypal material that undergoes a continuous phase transition to a ferroquadrupole-ordered state at 2.15 K. Above the phase transition, each Tm ion contributes an entropy of kB ln 2 due to the degeneracy of the crystal electric field groundstate. Owing to the large magnetoelastic coupling, which is a prerequisite for a material to undergo a phase transition via the cooperative Jahn--Teller effect, this level splitting, and hence the entropy, can be readily tuned by externally induced strain. Using a dynamic technique in which the strain is rapidly oscillated, we measure the adiabatic elastocaloric response of single-crystal TmVO4, and thus experimentally obtain the entropy landscape as a function of strain and temperature. The measurement confirms the suitability of this class of materials for cryogenic cooling applications and provides insight into the dynamic quadrupole strain susceptibility. [ABSTRACT FROM AUTHOR]

The suppression of ferroquadrupolar order in TmVO4 in a magnetic field is well-described by the transverse field Ising model, enabling detailed studies of critical dynamics near the quantum phase transition. We describe nuclear magnetic resonance measurements in pure and Y-doped single crystals. The non-Kramers nature of the ground state doublet leads to a unique form of the hyperfine coupling that exclusively probes the transverse field susceptibility. Our results show that this quantity diverges at the critical field, in contrast to the mean-field prediction. Furthermore, we find evidence for quantum critical fluctuations present near Tm-rich regions in Y-doped crystals at levels beyond which long-range order is suppressed, suggesting the presence of quantum Griffiths phases. [ABSTRACT FROM AUTHOR]

Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) are associated with motor impairments, with some children holding a comorbid diagnosis of Developmental Coordination Disorder (DCD). However, DCD is underdiagnosed in these populations and the volume abnormalities that contribute to explaining these motor impairments are poorly understood. In this study, motor abilities as measured by the Developmental Coordination Disorder Questionnaire (DCDQ) were compared between children with ADHD, children with ASD and typically developing (TD) children, aged 8–12 years old. Additionally, the association between the DCDQ scores (general coordination, fine motor/handwriting, control during movement, total) and regional volume abnormalities were explored in 6 regions of interest (pre-central gyrus, post-central gyrus, inferior parietal cortex, superior frontal gyrus, middle frontal gyrus, medial frontal gyrus), within each group and across all participants. Children with ASD and children with ADHD showed impaired motor abilities in all the DCDQ-derived scores compared to TD children. Additionally, most children with ASD or ADHD had an indication or suspicion of DCD. Within the ASD group, coordination abilities were associated with the volume of the right medial frontal gyrus, and within the ADHD group, the total DCDQ score was associated with the volume of the right superior frontal gyrus. This study underlines the importance of routinely checking motor abilities in populations with ASD or ADHD in clinical practise and contributes to the understanding of structural abnormalities subtending motor impairments in these disorders.

The overlap/distinctiveness between Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) has been increasingly investigated in recent years, particularly since the DSM-5 allows the dual diagnosis of ASD and ADHD, but the underlying brain mechanisms remain unclear. Although both disorders are associated with brain volumetric abnormalities, it is necessary to unfold the shared and specific volume abnormalities that could contribute to explain the similarities and differences in the clinical and neurocognitive profiles between ADHD and ASD. In this voxel-based morphometry (VBM) study, regional grey matter volumes (GMV) were compared between 22 children with ADHD, 18 children with ASD and 17 typically developing (TD) children aged 8 to 12 years old, controlling for age and total intracranial volume. When compared to TD children or children with ASD, children with ADHD had a larger left precuneus, and a smaller right thalamus, suggesting that these brain abnormalities are specific to ADHD relative to ASD. Overall, this study contributes to the delineation of disorder-specific structural abnormalities in ADHD and ASD.

Background: Differences in the reference intervals between dog breeds have been recognized for many years. Due to the importance of multi‐drug‐resistance 1‐deficient (MDR1) Collies in veterinary medicine, it is important to determine whether breed‐specific reference intervals are needed for this group. Objectives: The goal of this study was to establish plasma chemistry reference intervals for adult MDR1‐deficient Collies. Methods: Plasma samples collected from 110 healthy male and female adult MDR1‐deficient Collies were analyzed for 21 analytes on a Beckman AU480 clinical chemistry analyzer. Reference intervals were established using a nonparametric statistical method. Results: Reference intervals were established for 21 biochemical measurands in healthy adult MDR1‐deficient Collies. Conclusion: Plasma chemistry reference intervals for MDR1‐deficient Collies were clinically similar to intervals earlier created for Beagles. Intervals for male and female MDR1‐deficient Collies were very similar to each other. [ABSTRACT FROM AUTHOR]

Pre-hospital treatment of traumatic brain injury (TBI) with co-existing polytrauma is complicated by requirements for intravenous fluid volume vs. hypotensive resuscitation. A low volume, small particle-size-oxygen-carrier perfluorocarbon emulsion NVX-428 (dodecafluoropentane emulsion; 2% w/v) could improve brain tissue with minimal additional fluid volume. This study examined whether the oxygen-carrier NVX-428 shows safety and efficacy for pre-hospital treatment of TBI. Anesthetized swine underwent fluid percussion injury TBI and received 1 mL/kg IV NVX-428 (TBI-NVX) at 15 min (T15) or normal saline (no-treatment) (TBI-NON). Similarly, uninjured swine received NVX-428 (SHAM-NVX) or normal saline (SHAM-NON). Animals were monitored and measurements were taken for physiological and neurological parameters before euthanasia at the six-hour mark (T360). Histopathological analysis was performed on paraffin embedded tissues. Physiological, biochemical and blood gas parameters were not different, with the exception of a significant but transient increase in mean pulmonary artery pressure observed in the TBI-experimental group immediately after drug administration. There were no initial differences in brain oxygenation at baseline, but over time oxygen decreased ~50% in both TBI groups. Histological brain injury scores were similar between TBI-NVX and TBI-NON, although a number of subcategories (spongiosis-ischemic/dead neurons-hemorrhage-edema) in TBI-NVX had a tendency for lower scores. The cerebellum showed significantly lower spongiosis and ischemic/dead neuron injury scores and a lower number of Fluoro-Jade-B-positive cerebellar-Purkinje-cells after NVX-428 treatment compared to controls. NVX-428 may assist in mitigating secondary cellular brain damage.

The use of hemoglobin-based oxygen carriers (HBOC) as oxygen delivering therapies during hypoxic states has been hindered by vasoconstrictive side effects caused by depletion of nitric oxide (NO). OxyVita C is a promising oxygen-carrying solution that consists of a zero-linked hemoglobin polymer with a high molecular weight (~17 MDa). The large molecular weight is believed to prevent extravasation and limit NO scavenging and vasoconstriction. The aim of this study was to assess vasoactive effects of OxyVita C on systemic blood pressures and cerebral pial arteriole diameters. Anesthetized healthy rats received four intravenous (IV) infusions of an increasing dose of OxyVita C (2, 25, 50, 100 mg/kg) and hemodynamic parameters and pial arteriolar diameters were measured pre- and post-infusion. Normal saline was used as a volume-matched control. Systemic blood pressures increased (P ≤ 0.05) with increasing doses of OxyVita C, but not with saline. There was no vasoconstriction in small (

This article describes the use of an online survey tool called Survey Monkey, which can be used by school social workers and school social work educators for evaluation of practice, needs assessment, and program evaluation. Examples of questions are given. Principles of writing good survey questions are described. (Contains 2 tables and 1 footnote.)

Students and other members of a school community frequently experience grief and loss. This article uses a dual process model to describe students' grief and loss. It also describes the manifestations of grief at different stages of children's development, as well as interventions at different levels of the school environment. The ability to help others with the grief process begins with the school social worker's understanding of his or her own loss issues. Other important tasks for the school social worker include training other adults to help students with these issues and helping to create a caring community in the school.