Nanometre-scale optical property fluctuations in Cu2ZnSnS4 revealed by low temperature cathodoluminescence

Band tailing is a major contributing factor to the large open circuit voltage (Voc) deficit that is currently limiting Cu2ZnSnS4 (CZTS) photovoltaic devices. It occurs in highly doped, highly compensated semiconductors and gives rise to a non-uniform electronic band structure. Here we report spatially resolved fluctuations in CZTS optical properties using low temperature cathodoluminescence (CL) in a scanning electron microscope (SEM). Principal component analysis reveals three CL peaks whose relative intensity vary across domains ~ 100 nm in size. It is not known whether the non-uniform optical properties are due to changes in composition or due to structural order-disorder at constant composition. Measurement of composition with energy dispersive X-ray (EDX) analysis in an SEM and ordering with Micro-Raman mapping revealed CZTS to be uniform within the spatial resolution (estimated at ~ 0.4 µm and 1.1 µm respectively) and sensitivity of the two techniques. The CL results are consistent with the presence of band tailing in CZTS

Relating resting-state fMRI and EEG whole-brain connectomes across frequency bands.

Whole brain functional connectomes hold promise for understanding human brain activity across a range of cognitive, developmental and pathological states. So called resting-state (rs) functional MRI studies have contributed to the brain being considered at a macroscopic scale as a set of interacting regions. Interactions are defined as correlation-based signal measurements driven by blood oxygenation level dependent (BOLD) contrast. Understanding the neurophysiological basis of these measurements is important in conveying useful information about brain function. Local coupling between BOLD fMRI and neurophysiological measurements is relatively well defined, with evidence that gamma (range) frequency EEG signals are the closest correlate of BOLD fMRI changes during cognitive processing. However, it is less clear how whole-brain network interactions relate during rest where lower frequency signals have been suggested to play a key role. Simultaneous EEG-fMRI offers the opportunity to observe brain network dynamics with high spatio-temporal resolution. We utilize these measurements to compare the connectomes derived from rs-fMRI and EEG band limited power (BLP). Merging this multi-modal information requires the development of an appropriate statistical framework. We relate the covariance matrices of the Hilbert envelope of the source localized EEG signal across bands to the covariance matrices derived from rs-fMRI with the means of statistical prediction based on sparse Canonical Correlation Analysis (sCCA). Subsequently, we identify the most prominent connections that contribute to this relationship. We compare whole-brain functional connectomes based on their geodesic distance to reliably estimate the performance of the prediction. The performance of predicting fMRI from EEG connectomes is considerably better than predicting EEG from fMRI across all bands, whereas the connectomes derived in low frequency EEG bands resemble best rs-fMRI connectivity

Part of the Family:Children’s Experiences with Their Companion Animals in the Context of Domestic Violence and Abuse

Purpose: Children who experience Domestic Violence and Abuse (DVA) draw on a range of strategies to manage the complex dynamics of family life. This article explored children’s experiences of their relationships with pets and other animals, considering how children understood these relationships.Methods: This qualitative study is based on semi-structured interviews and visual methods-based research with 22 children (aged 9–17), drawn from a larger study on how children cope with DVA. The data were analysed using reflexive thematic analysis.Findings: Five themes are discussed: Part of the family explores how children positioned animals as relational beings who occupied an important place in their lives; caring for animals considers the reciprocal caring relationship children described; listening and support details how children interacted with animals to allow themselves to feel more heard and supported; in the theme control and abuse, we consider children’s experiences of perpetrators’ use of companion animals as part of a pattern of abuse and control; and in disruption, uncertainty and loss, we discuss how children feel and relate to their animals when leaving situations of domestic abuse.Conclusions: The implications of our analysis are considered in relation to providing support for children impacted by domestic abuse, and the importance of ensuring companion animals are provided for in housing policy and planning for domestic abuse survivors

Épica, crónicas y genealogías. En torno a la historicidad de la Leyenda de los infantes de Lara

[ES] Este trabajo analiza la historicidad de la narración épica conocida como Leyenda de los Infantes de Lara. Frente a la visión tradicional, que atribuía a este relato una gran fidelidad a los hechos históricos, se sugiere una imagen más compleja, que mezcla elementos nuevos y más antiguos: 1) Un posible núcleo histórico consistente en la historia de Ruy Velázquez; 2) Una parte más compacta formada por la trama de la venganza de sangre, que enlaza la traición con la venganza de Mudarra. Frente a la idea tradicional de que la venganza es una completa ficción elaborada mucho tiempo después, se sugiere que traición y venganza constituyen una unidad lógica, aunque no se relacione con hechos históricos concretos. Es muy probable que el núcleo central de la leyenda, tal y como nos ha llegado, sea más bien un conjunto amplio de temas y motivos entretejidos con hechos históricos más o menos desfigurados. Finalmente, todas estas piezas cobran sentido en su contexto geográfico: la leyenda parece estar reflejando un conflicto entre Lara y Salas, leído desde el punto de vista de Salas, con una clara hostilidad hacia Lara.Peer reviewe

Variable echo time imaging for detecting the short T2* components of the sciatic nerve: a validation study

OBJECTIVE: The aim of this study was to develop and validate an MRI protocol based on a variable echo time (vTE) sensitive to the short T2* components of the sciatic nerve. MATERIALS AND METHODS: 15 healthy subjects (M/F: 9/6; age: 21-62) were scanned at 3T targeting the sciatic nerve at the thigh bilaterally, using a dual echo variable echo time (vTE) sequence (based on a spoiled gradient echo acquisition) with echo times of 0.98/5.37 ms. Apparent T2* (aT2*) values of the sciatic nerves were calculated with a mono-exponential fit and used for data comparison. RESULTS: There were no significant differences in aT2* related to side, sex, age, and BMI, even though small differences for side were reported. Good-to-excellent repeatability and reproducibility were found for geometry of ROIs (Dice indices: intra-rater 0.68-0.7; inter-rater 0.70-0.72) and the related aT2* measures (intra-inter reader ICC 0.95-0.97; 0.66-0.85) from two different operators. Side-related signal-to-noise-ratio non-significant differences were reported, while contrast-to-noise-ratio measures were excellent both for side and echo. DISCUSSION: Our study introduces a novel MR sequence sensitive to the short T2* components of the sciatic nerve and may be used for the study of peripheral nerve disorders

Appropriate use criteria for transesophageal echocardiography in Greece: A single center experience

Introduction The American College of Cardiology Foundation (ACCF) along with the American Society of Echocardiography (ASE) have enabled an accurate and clinically oriented evaluation of echocardiography indications by introducing Appropriate Use Criteria (AUC). Aim This study was designed to evaluate the degree of implementation of AUC for transesophageal echocardiography (TEE) during daily clinical practice in a tertiary university hospital in Greece during the era of economic recession. Materials and Methods From November 2014 to May 2014, we prospectively enrolled 300 patients who were examined in the Echocardiography Laboratory of the First University Cardiology. We recorded the participants' demographic and clinical characteristics using questionnaires and followed a scoring process according to ACCF guidelines to classify patients into an appropriate, inappropriate or uncertain category. The primary endpoint was to assess the association between the class of appropriateness and abnormal TEE results. Results In 89.4% of patients labelled appropriate, TEE was abnormal and significantly higher compared to patients of uncertain eligibility (50%) and to patients for whom TEE was considered to be inappropriate (35%) (p < 0.001). Subgroup analysis revealed a positive association between AUC and an increased possibility for abnormal TEE in female subjects (p = 0.001) as well as in patients who were younger than 50 years old (p < 0.001). A significant association was finally established between AUC and abnormal findings in TEE in patients with no risk factors (p = 0.028) and in patients with more than 3 risk factors (p = 0.013). Conclusion TEE constitutes a medical practice with an optimal cost/effectiveness ratio and should be further encouraged in our country in accordance with the austerity policy as long as the AUC are generally applied

Investigation of the effects of atmospheric pressure cold plasma on human cells and tissues

Atmospheric pressure cold plasma (APCP) is a novel tool in medicine for tissue disinfection. We recently reported that 2 minutes of APCP generated by a new portable device that ionizes a flow of helium gas exerted an antimicrobial effect, mainly due to the action of reactive oxygen species (ROS) (P. Brun et al., 2012). Since ROS induced DNA lesions that could lead to point mutations, before using plasma in medical treatment it is important to ascertain the safe usage of this device. In the study presented, we analysed the presence of ROS levels, pre-mutagenic 8-oxodeoxyguanosine (8-OHdG) and the expression of OGG1, a DNA glycosylase specific for the removal of 8-OHdG lesions in cell (fibroblasts and keratocytes) cultures. ROS levels in APCP-exposed microorganisms and keratocytes were detected by 2’,7’-dichlorofluorescein diacetate (HDCF-DA) fluorescence; the potential genotoxic effects of plasma were evaluated by analyses of cell cycle distribution, externalization of phosphatidylserine, HPLC determination of 8-OHdG expression, qRT-PCR and Western blotting of OGG1 gene and protein, at set time intervals. Our results demonstrated that APCP induced ROS formation in exposed human cells, a transient 8-OHdG expression and a consequent adaptative OGG1 response at the transcriptional and translational level. In conclusion, the short application of APCP to cells and tissues has a disinfection effect and leads to time-restricted ROS generation and to oxidative-stress related responses

Pilot Study on Quantitative Cervical Cord and Muscular MRI in Spinal Muscular Atrophy: Promising Biomarkers of Disease Evolution and Treatment?

Introduction: Nusinersen is a recent promising therapy approved for the treatment of spinal muscular atrophy (SMA), a rare disease characterized by the degeneration of alpha motor neurons (αMN) in the spinal cord (SC) leading to progressive muscle atrophy and dysfunction. Muscle and cervical SC quantitative magnetic resonance imaging (qMRI) has never been used to monitor drug treatment in SMA. The aim of this pilot study is to investigate whether qMRI can provide useful biomarkers for monitoring treatment efficacy in SMA. Methods: Three adult SMA 3a patients under treatment with nusinersen underwent longitudinal clinical and qMRI examinations every 4 months from baseline to 21-month follow-up. The qMRI protocol aimed to quantify thigh muscle fat fraction (FF) and water-T2 (w-T2) and to characterize SC volumes and microstructure. Eleven healthy controls underwent the same SC protocol (single time point). We evaluated clinical and imaging outcomes of SMA patients longitudinally and compared SC data between groups transversally. Results: Patient motor function was stable, with only Patient 2 showing moderate improvements. Average muscle FF was already high at baseline (50%) and progressed over time (57%). w-T2 was also slightly higher than previously published data at baseline and slightly decreased over time. Cross-sectional area of the whole SC, gray matter (GM), and ventral horns (VHs) of Patients 1 and 3 were reduced compared to controls and remained stable over time, while GM and VHs areas of Patient 2 slightly increased. We found altered diffusion and magnetization transfer parameters in SC structures of SMA patients compared to controls, thus suggesting changes in tissue microstructure and myelin content. Conclusion: In this pilot study, we found a progression of FF in thigh muscles of SMA 3a patients during nusinersen therapy and a concurrent slight reduction of w-T2 over time. The SC qMRI analysis confirmed previous imaging and histopathological studies suggesting degeneration of αMN of the VHs, resulting in GM atrophy and demyelination. Our longitudinal data suggest that qMRI could represent a feasible technique for capturing microstructural changes induced by SMA in vivo and a candidate methodology for monitoring the effects of treatment, once replicated on a larger cohort

Proteomic analysis of the Plasmodium male gamete reveals the key role for glycolysis in flagellar motility.

BACKGROUND: Gametogenesis and fertilization play crucial roles in malaria transmission. While male gametes are thought to be amongst the simplest eukaryotic cells and are proven targets of transmission blocking immunity, little is known about their molecular organization. For example, the pathway of energy metabolism that power motility, a feature that facilitates gamete encounter and fertilization, is unknown. METHODS: Plasmodium berghei microgametes were purified and analysed by whole-cell proteomic analysis for the first time. Data are available via ProteomeXchange with identifier PXD001163. RESULTS: 615 proteins were recovered, they included all male gamete proteins described thus far. Amongst them were the 11 enzymes of the glycolytic pathway. The hexose transporter was localized to the gamete plasma membrane and it was shown that microgamete motility can be suppressed effectively by inhibitors of this transporter and of the glycolytic pathway. CONCLUSIONS: This study describes the first whole-cell proteomic analysis of the malaria male gamete. It identifies glycolysis as the likely exclusive source of energy for flagellar beat, and provides new insights in original features of Plasmodium flagellar organization

a novel plasma source for sterilization of living tissues

A source for the production of low-power plasmas at atmospheric pressure, to be used for the nondamaging sterilization of living tissues, is presented. The source, powered by radiofrequency and working with a helium flow, has a specific configuration, studied to prevent the formation of electric arcs dangerous to living matter. It is capable of killing different types of bacteria with a decimal reduction time of 1?2?min; on the contrary, human cells such as conjunctival fibroblasts were found to be almost unharmed by the plasma. A high concentration of OH radicals, likely to be the origin of the sterilizing effect, is detected through their UV emission lines. The effect of the UV and the OH radicals on the fibroblasts was analysed and no significant effects were detected