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Aim: Our aim was to assess the population structure, genetic diversity and demographic history of the wolverine (Gulo gulo) throughout its entire Eurasian range. Additionally, we aimed to contextualize and put into perspective the state of the endangered Fennoscandian population by emphasizing its connectivity to other populations. Location: The main study area covered most of the Eurasian wolverine range, with samples from Finland, Russia, Kazakhstan and Mongolia. Methods: Using a 495 bp fragment of the mitochondrial DNA control region and a frequently used set of 14 microsatellite markers on an extensive dataset of samples, we assessed the population structure, genetic diversity, and demographic history of wolverines with a variety of population genetic analyses. Results: According to both nuclear and mitochondrial genetic markers, Eurasian wolverines exhibit substructure, with the most distinct population located in Fennoscandia. The Fennoscandian population has undergone a genetic bottleneck, likely influencing its genetic diversity, which is notably the lowest in Eurasia. Genetic diversity in the rest of Eurasia gradually rises towards the central part of the range and decreases again in the east, although not as significantly as in the west. Main Conclusions: This study reveals the population structure of wolverines across Eurasia and provides direction for allocating conservation efforts to sustain a diverse and connected wolverine population. While most of the Eurasian populations seem to be well‐connected and genetically diverse, the Fennoscandian wolverines may need better connectivity to the other Eurasian populations to ensure gene flow and long‐term persistence. Our study further highlights the importance of considering the population genetic structure and diversity of the entire species range when planning management strategies. [ABSTRACT FROM AUTHOR]

Introduction: There is an increasing emphasis on exploring ways to improve students' transition from the classroom into the clinical environment. Diagnostic radiography (DR) students undergo rigorous theoretical and practical training before they are exposed to the clinical environment. It has been found that when DR students commence clinical learning in the workplace for the very first time, they experience difficulties in this transition. At the site of investigation, a newly integrated and dedicated clinical preparedness (CP) programme was offered; however, little is known about the DR students' perceptions of this programme. Methods: A qualitative approach coupled with a self‐developed, cross‐sectional research tool was employed. First‐year DR students were purposefully sampled against the inclusion and exclusion criteria. The principle of voluntary participation was upheld throughout the data collection process. The data were analysed using Braun and Clarke's six steps of thematic analysis. Results: Forty‐two responses were collected. Following a thematic analysis, two overarching themes were developed, namely: (1) reflections on the CP programme and (2) suggestions for future CP programmes. Conclusion: This study demonstrated the need for effective CP programmes as an approach to ease the transition of first‐year DR students from the classroom into the clinical environment. Several suggestions, for example, an extended CP programme and a clinical information pack were made for the offering of similar programmes in the future. [ABSTRACT FROM AUTHOR]

Anthropogenic pressures on nature have been causing population declines for centuries. Intensified persecution of apex predators, like the golden eagle, resulted in population bottlenecks during the 19th and 20th centuries. To study population genetics and demographic history of the golden eagle throughout its distribution, we collected museum samples from previously underrepresented regions, such as Russia and Central Asia. We used 12 microsatellite loci and a fragment of the mitochondrial DNA control region to re‐evaluate phylogeography of Eurasian golden eagles and study the impacts of the population bottleneck. Our results revealed a north–south genetic gradient, expressed by the difference between Mediterranean and Holarctic lineages, as well as genetically distinct Northern Europe and Central Asia and Caucasus regions. Furthermore, Northern Europe exhibited the lowest, whereas Central Asia and Caucasus had the highest genetic diversity. Although golden eagles maintained relatively high genetic diversity, we detected genetic signatures of the recent bottleneck, including reduced genetic diversity and a decline in the effective female population size around the year 1975. Our study improves the knowledge of the genetic composition of Eurasian golden eagles and highlights the importance of understanding their historical population dynamics in the face of ongoing and future conservation efforts. [ABSTRACT FROM AUTHOR]

Soil crusting (surface sealing) is widespread and serious in ecotouristic game parks and reserves in southern Africa, and especially South Africa. In this study, mineral soil crusts were found to be the problem in the Dinokeng Game Reserve (DGR), South Africa. Large areas of bare soil crusted areas were found in this reserve. The cause of this crusting was found to be historical agricultural practices such as cultivation with maize on non-arable soils and overgrazing by cattle. Negative impacts of soil crusting include reduction of water infiltration, leading to increased runoff and erosion and induced drought; inhibiting soil aeration; inhibiting germination and seedling emergence; and inhibiting root functioning and development. In this study in the DGR, a bare crusted area, where cultivation was abandoned 50 years before and there has been no recovery to rangeland since then, was selected for a field trial to determine the effectiveness of the application of various soil ameliorants on soil crust alleviation and improvement of water infiltration rate. The following ameliorants were evaluated: polyacrylamide (PAM) at levels of 5 and 20 kg/ha, gypsum at 2.5 t/ha, and molasses meal at 5 t/ha, as well as combinations of PAM and molasses meal, PAM and gypsum and gypsum and molasses meal. Brush packing, without any ameliorant applied, was also included as treatment, as well as a control with no treatments. PAM treatments increased final infiltration rate (FIR) by between 100–206%. The high efficacy of the lowest PAM treatment is at a cost of only USD 15 per hectare economically important. On the studied soil gypsum application reduced FIR by 81%, while molasses meal had minimal effect. These ameliorants can therefore not be recommended on such soil. [ABSTRACT FROM AUTHOR]

The excellent features of non‐invasive molecular imaging, its progressive technology (real‐time, whole‐body imaging and quantification), and global impact by a growing infrastructure for positron emission tomography (PET) scanners are encouraging prospects to investigate new concepts, which could transform clinical care of complex infectious diseases. Researchers are aiming towards the extension beyond the routinely available radiopharmaceuticals and are looking for more effective tools that interact directly with causative pathogens. We reviewed and critically evaluated (challenges or pitfalls) antibiotic‐derived PET radiopharmaceutical development efforts aimed at infection imaging. We considered both radiotracer development for infection imaging and radio‐antibiotic PET imaging supplementing other tools for pharmacologic drug characterization; overall, a total of 20 original PET radiotracers derived from eleven approved antibiotics. [ABSTRACT FROM AUTHOR]

There are several possible mechanisms by which combined oral contraceptives (COC) use increase venous thromboembolism (VTE) risk. Melodene® is a monophasic COC containing the third‐generation progestin Gestodene (GSD), which is associated with increased risk of VTE. Therefore, the aim of this study was to investigate the possible alterations in viscoelastic parameters of whole blood and plasma clots along with the biophysical characteristics of erythrocytes and specifically fibrin fibers in females using a COC containing GSD. GSD appeared to have a significant impact on the biophysical characteristics of fibrin fiber networks. When GSD is combined with ethinylestradiol the viscoelastic properties of whole blood clots tend to become more prothrombotic. The alterations to and aggregation of erythrocytes accompanied with spontaneous formation of a fibrin "blanket" provides a possible mechanism for the increased occurrence of "red" clots, which can lead to occlusions in the vascular system. Thus, the increased risk of VTE associated with these COCs can be attributed to these erythrocyte‐and‐fibrin‐rich‐clots occluding venous vessels. However, our findings also propose that these changes to the biophysical properties of both erythrocytes and fibrin, specifically spontaneous expansion of deformed fibrin networks, can also occlude vessels in the microcirculation, which could have lasting, subclinical complications for female users. We recommend that a thorough risk assessment, with specific focus on coagulation and other factors affecting fibrin formation, be done for each female before prescribing a GSD‐containing COC. Females that "qualify" then need to be monitored on a regular basis to lower the risk of thrombotic events. Research Highlights: Gestodene in combination with ethinyl estradiol significantly impacts the biophysical characteristics of erythrocytes and fibrin fiber networks.These changes, specifically spontaneous expansion of deformed fibrin networks, can occlude vessels in the microcirculation, which could have lasting, subclinical complications for the female user.The changes observed for specifically erythrocytes and fibrin show that the hormone formulation investigated contribute to a thrombogenic profile for female users [ABSTRACT FROM AUTHOR]

Abstract: Chiral analysis of dl‐amino acids was achieved by micellar electrokinetic chromatography coupled with UV‐excited fluorescence detection. The fluorescent reagent (+)‐1‐(9‐fluorenyl)ethyl chloroformate was employed as chiral amino acid derivatizing agent and sodium dodecyl sulfate served as pseudo‐stationary phase for separating the formed amino acid diastereomers. Sensitive analysis of (+)‐1‐(9‐fluorenyl)ethyl chloroformate‐amino acids was achieved applying a xenon‐mercury lamp for ultraviolet excitation, and a spectrograph and charge‐coupled device for wavelength‐resolved emission detection. Applying signal integration over a 30 nm emission wavelength interval, signal‐to‐noise ratios for derivatized amino acids were up to 23 times higher as obtained using a standard photomultiplier for detection. The background electrolyte composition (electrolyte, pH, sodium dodecyl sulfate concentration, and organic solvent) was studied in order to attain optimal chemo‐ and enantioseparation. Enantioseparation of 12 proteinogenic dl‐amino acids was achieved with chiral resolutions between 1.2 and 7.9, and detection limits for most derivatized amino acids in the 13–60 nM range (injected concentration). Linearity (coefficients of determination > 0.985) and peak‐area and migration‐time repeatabilities (relative standard deviations lower than 2.6 and 1.9%, respectively) were satisfactory. The employed fluorescence detection system provided up to 100‐times better signal‐to‐noise ratios for (+)‐1‐(9‐fluorenyl)ethyl chloroformate‐amino acids than ultraviolet absorbance detection, showing good potential for d‐amino acid analysis. [ABSTRACT FROM AUTHOR]

The complexity associated with how interventions result—or fail to result—in outcomes and how context matters is increasingly recognised. Logic models provide an important tool for handling complexity, with contrasting uses in programme evaluation and evidence synthesis. To reconcile these, we developed an approach that combines the strengths of both traditions, propose a taxonomy of logic models, and provide guidance on how to choose between approaches and types of logic models in systematic reviews and health technology assessments (HTA). The taxonomy distinguishes 3 approaches (a priori, staged, and iterative) and 2 types (systems‐based and process‐orientated) of logic models. An a priori logic model is specified at the start of the systematic review/HTA and remains unchanged. With a staged logic model, the reviewer prespecifies several points, at which major data inputs require a subsequent version. An iterative logic model is continuously modified throughout the systematic review/HTA process. System‐based logic models describe the system, in which the interaction between participants, intervention, and context takes place; process‐orientated models display the causal pathways leading from the intervention to multiple outcomes. The proposed taxonomy of logic models offers an improved understanding of the advantages and limitations of logic models across the spectrum from a priori to fully iterative approaches. Choice of logic model should be informed by scope of evidence synthesis, presence/absence of clearly defined population, intervention, comparison, outcome (PICO) elements, and feasibility considerations. Applications across distinct interventions and methodological approaches will deliver good practice case studies and offer further insights on the choice and implementation of logic modelling approaches. [ABSTRACT FROM AUTHOR]

Background: Evidence synthesis has seen major methodological advances in reducing uncertainty and estimating the sizes of the effects. Much less is known about how to assess the relative value of different outcomes. Objective: To identify studies that assessed preferences for outcomes in health conditions. Methods: Search strategy: we searched MEDLINE, EMBASE, PsycINFO and the Cochrane Library in February 2014. Inclusion criteria: eligible studies investigated preferences of patients, family members, the general population or healthcare professionals for health outcomes. The intention of this review was to include studies which focus on theoretical alternatives; studies which assessed preferences for distinct treatments were excluded. Data extraction: study characteristics as study objective, health condition, participants, elicitation method, and outcomes assessed in the study were extracted. Main results: One hundred and twenty‐four studies were identified and categorized into four groups: (1) multi criteria decision analysis (MCDA) (n = 71), (2) rating or ranking (n = 25), (3) utility eliciting (n = 5) and (4) studies comparing different methods (n = 23). The number of outcomes assessed by method group varied. The comparison of different methods or subgroups within one study often resulted in different hierarchies of outcomes. Conclusions: A dominant method most suitable for application in evidence syntheses was not identified. As preferences of patients differ from those of other stakeholders (especially medical professionals), the choice of the group to be questioned is consequential. Further research needs to focus on validity and applicability of the identified methods. [ABSTRACT FROM AUTHOR]

Unlabelled: A systematic review and meta-analysis were performed to determine the effect of therapeutic hypothermia using low-technology methods, in settings with facilities for intensive care, in term or near-term infants with hypoxic-ischaemic encephalopathy on mortality, neurological morbidity at discharge and neurological morbidity at 6-24 months.Conclusion: Meta-analysis of three randomised controlled studies showed that low-technology therapeutic hypothermia in an intensive care setting significantly reduced the mortality and the neurological morbidity in survivors at discharge. [ABSTRACT FROM AUTHOR]

Rationale, aims and objectives The physician assistant ( PA) is trained to perform clinical tasks traditionally performed by medical doctors ( MDs). Previous research showed no difference in the level of clinical skills of PAs compared with MDs in a specific niche, that is the specialty in which they are employed. However, MDs as well as PAs working within a specialty have to be able to recognize medical problems in the full scope of medicine. The objective is to examine PA students' level of general clinical skills across the breadth of clinical cases. Method A cross-sectional study was conducted. PA students and recently graduated MDs in the Netherlands were observed on their clinical skills by means of an objective structured clinical examination comprising five stations with common medical cases. The level of mastering history taking, physical examination, communication and clinical reasoning of PA students and MDs were described in means and standard deviation. Cohen's d was used to present effect sizes. Results PA students and MDs score about equal on history taking ( PA 5.8 ± 0.8 vs. MD 5.7 ± 0.7), physical examination ( PA 4.8 ± 1.3 vs. MD 5.4 ± 0.8) and communication ( PA: 8.2 ± 0.8 vs. MD: 8.6 ± 0.5) in the full scope of medicine. In the quality of the report, including the patient management plan, PA students scored a mean of 6.0 ± 0.6 and MDs 6.8 ± 0.6. Conclusions In this setting in the Netherlands, PA students and MDs score about equal in the appraisal of common cases in medical practice. The slightly lower scores of PA students' clinical reasoning in the full scope of clinical care may have raise attention to medical teams working with PAs and PA training programmes. [ABSTRACT FROM AUTHOR]

ABSTRACT A method of constructing multiband filtering functions from single-band functions using rational reactance mapping functions is presented. The technique can be applied to coupled-resonator filters with N pass-bands, each of arbitrary bandwidth and centre frequency. The resulting filter topologies are simple to implement and do not introduce cross-couplings beyond that of the original low-pass prototype. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:81-92, 2015. [ABSTRACT FROM AUTHOR]

Exercise training reduces sympathetic activity in hypertensive humans and rats. We hypothesized that the swimming exercisewould change the neurotransmission in the rostral ventrolateral medulla (RVLM), a key region involved in sympathetic outflow, and hemodynamic control in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Bilateral injections of kynurenic acid (KYN) were carried out in the RVLM in sedentary- (S-) or exercised- (E-) SHR and WKY rats submitted to swimming for 6 weeks. Rats were α-chloralose anesthetized and artificially ventilated, with Doppler flow probes around the lower abdominal aorta and superior mesenteric artery. Injections into the RVLM were made before and after i.v. L-NAME (nitric oxide synthase, NOS, inhibitor). Injections of KYN into the RVLM elicited a major vasodilation in the hindlimbmore than in the mesenteric artery in E-SHR compared to S-SHR, but similar decrease in arterial pressure was observed in both groups. Injections of KYN into the RVLM after i.v. L-NAME attenuated the hind limb vasodilation evoked by KYN and increased the mesenteric vasodilation in ESHR. Swimming exercise can enhance the hindlimb vasodilation mediated by peripheral NO release, reducing the activation of neurons with EAA receptors in the RVLM in SHR. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To compare 2 routine obstetric ultrasound protocols regarding number of clinically relevant events detected and total ultrasound workload. Methods: An interventional before-and-after study comparing 2 groups of 750 consecutive low-risk pregnant women was conducted. The 1st group was routinely offered mid-trimester ultrasound and selective ultrasound examinations for specific indications; the 2nd group was, in addition to this, offered a scan at 1st prenatal visit. Results: The groups were comparable at baseline, and 78% underwent booking scan. The expanded protocol showed no improvement in detection of most clinically relevant findings but did detect twins slightly earlier (P =0.3) and significantly reduced the number of presumed post-term deliveries (8.4% vs 13.1%; OR 0.61 [95% CI, 0.41–0.90]). Although more women were scanned at any point or <24weeks (P <0.001), the increase in women receiving a properly timed fetal anomaly scan was small (60.7% vs 52.3%; P =0.003). Total ultrasound workload increased by 74%, mainly because of more follow-up scans (323 vs 122) and more women being scanned for the 1st time >24weeks (146 vs 51; P <0.001). Conclusion: The results do not support a policy of routine booking scans and revealed no significant benefit apart from a small reduction in presumed post-term pregnancies. [Copyright &y& Elsevier]

SUMMARY Variation in masticatory induced stress, caused by shape changes in the human skull, is quantified in this article. A comparison on masticatory induced stress is presented subject to a variation in human skull shape. Non-rigid registration is employed to obtain appropriate computational domain representations. This procedure allows the isolation of shape from other variations that could affect the results. An added benefit, revealed through the use of non-rigid registration to acquire appropriate domain representation, is the possibility of direct and objective comparison and manipulation. The effect of mapping uncertainty on the direct comparison is also quantified. As shown in this study, exact difference values are not necessarily obtained, but a non-rigid map between subject shapes and numerical results gives an objective indication on the location of differences. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A goal in proteomics is the analysis of proteins by LC-MS. The proteins are enzymatically digested and the resulting peptides are chromatographically separated and introduced into a tandem MS. The obtained MS data are used for a search in sequence databases, providing identification scores for the proteins. A method to improve that score is to increase the chromatographic separation and peak capacity. In this study, the chromatographic conditions were optimized for a relatively large gradient time by varying the flow rate and gradient composition. The influence of the monolithic column length (15 and 64 cm) and particle diameter (1.8 μm; 15-cm length) on the sample peak capacity, productivity and identification score was studied. For comparison of gradient systems, a scaling factor was introduced to normalize the properties/performance of columns for material, diameter and length. As model proteins/digests, a simple (myoglobin) and a larger (BSA) protein were used. The smallest peak width, highest identification scores (54 and 89% for BSA and myoglobin, respectively) and productivity (5.0 and 4.0, respectively) were obtained for the 15-cm particulate column. The study also demonstrates that a further increase in the chromatographic performance is beneficial for BSA but hardly increases the identification score for the relatively small myoglobin. [ABSTRACT FROM AUTHOR]