Semen quality detection using time of flight and acoustic wave sensors

We report a real-time technique for assessing the number of motile sperm in a semen sample. The time of flight technique uses a flow channel with detection at the end of the channel using quartz crystal microbalances. Data presented suggests that a simple rigid mass model may be used in interpreting the change in resonant frequency using an effective mass for the sperm

The Spitzer c2d Survey of Nearby Dense Cores. V. Discovery of a VeLLO in the "Starless" Dense Core L328

This paper reports the discovery of a Very Low Luminosity Object (VeLLO) in the "starless" dense core L328, using the Spitzer Space Telescope and ground based observations from near-infrared to millimeter wavelengths. The Spitzer 8 micron image indicates that L328 consists of three subcores of which the smallest one may harbor a source, L328-IRS while two other subcores remain starless. L328-IRS is a Class 0 protostar according to its bolometric temperature (44 K) and the high fraction ~72 % of its luminosity emitted at sub-millimeter wavelengths. Its inferred "internal luminosity" (0.04 - 0.06 Lsun) using a radiative transfer model under the most plausible assumption of its distance as 200 pc is much fainter than for a typical protostar, and even fainter than other VeLLOs studied previously. Note, however, that its inferred luminosity may be uncertain by a factor of 2-3 if we consider two extreme values of the distance of L328-IRS (125 or 310 pc). Low angular resolution observations of CO do not show any clear evidence of a molecular outflow activity. But broad line widths toward L328, and Spitzer and near-infrared images showing nebulosity possibly tracing an outflow cavity, strongly suggest the existence of outflow activity. Provided that an envelope of at most ~0.1 Msunis the only mass accretion reservoir for L328-IRS, and the star formation efficiency is close to the canonical value ~30%, L328-IRS has not yet accreted more than 0.05 Msun. At the assumed distance of 200 pc, L328-IRS is destined to be a brown dwarf.Comment: 29 pages, 8 figures, 1 table, to be published in Astrophysical Journa

Adverse effects of adenovirus-mediated gene transfer of human transforming growth factor beta 1 into rabbit knees

To examine the effect of transforming growth factor (TGF)-β1 on the regulation of cartilage synthesis and other articular pathologies, we used adenovirus-mediated intra-articular gene transfer of TGF-β1 to both naïve and arthritic rabbit knee joints. Increasing doses of adenoviral vector expressing TGF-β1 were injected into normal and antigen-induced arthritis rabbit knee joints through the patellar tendon, with the same doses of an adenoviral vector expressing luciferase injected into the contralateral knees as the control. Intra-articular injection of adenoviral vector expressing TGF-β1 into the rabbit knee resulted in dose-dependent TGF-β1 expression in the synovial fluid. Intra-articular TGF-β1 expression in both naïve and arthritic rabbit knee joints resulted in significant pathological changes in the rabbit knee as well as in adjacent muscle tissue. The observed changes induced by elevated TGF-β1 included inhibition of white blood cell infiltration, stimulation of glycosaminoglycan release and nitric oxide production, and induction of fibrogenesis and muscle edema. In addition, induction of chondrogenesis within the synovial lining was observed. These results suggest that even though TGF-β1 may have anti-inflammatory properties, it is unable to stimulate repair of damaged cartilage, even stimulating cartilage degradation. Gene transfer of TGF-β1 to the synovium is thus not suitable for treating intra-articular pathologies

Substantial subpial cortical demyelination in progressive multiple sclerosis: have we underestimated the extent of cortical pathology?

Aim: Multiple sclerosis (MS) is an inflammatory demyelinating and neurodegenerative disease. Much of the complex symptomatology relates to pathology outside the classic white matter plaque, whereby lesions of the cortical grey matter, which are difficult to resolve by conventional clinical imaging, are in part predictive of outcome. We investigated the extent of grey matter pathology in whole coronal macrosections to reassess the contribution of cortical pathology to total demyelinating lesion area in progressive MS. Methods: Twenty-two cases of progressive MS were prepared as whole bi-hemispheric macrosections for histology, immunostaining and quantitative analysis of lesion number and relative area, leptomeningeal inflammation and microglial/macrophage activation. Results: Cortical grey matter demyelination was seen in all cases, which was more extensive than in white and deep grey matter (hippocampus, thalamus and basal ganglia) and accounted for 0.8%-60.2% of the entire measurable cortical ribbon. The pattern of cortical grey matter demyelination was predominantly subpial (mean 90.9%, range 60%-100%, of total cortical grey matter lesion area) and cases with the largest areas of subpial cortical lesions had more and larger deep grey matter lesions, greater numbers of activated microglia/macrophages, both in lesions as well as in normal cortical grey matter, together with elevated leptomeningeal inflammation and lymphoid-like structures. White matter lesion area was unchanged when compared with the progressive MS cases with little subpial cortical demyelination. Conclusion: Analysis of whole coronal macrosections reveals cortical demyelination is more extensive than reported by conventional histological methods. Cases of progressive MS with substantial subpial cortical demyelination that is independent of underlying white matter lesion area support the implications that these lesions may in-part arise through different pathogenetic mechanisms. Biomarkers and/or imaging correlates of this subpial pathology are required if we are to fully comprehend the clinical disease process

Quality of caesarean delivery services and documentation in first-line referral facilities in Afghanistan: a chart review

<p>Abstract</p> <p>Background</p> <p>Increasing appropriate use and documentation of caesarean section (CS) has the potential to decrease maternal and perinatal mortality in settings with low CS rates. We analyzed data collected as part of a comprehensive needs assessment of emergency obstetric and newborn care (EmONC) facilities in Afghanistan to gain a greater understanding of the clinical indications, timeliness, and outcomes of CS deliveries.</p> <p>Methods</p> <p>Records were reviewed at 78 government health facilities expected to function as EmONC providers that were located in secure areas of the country. Information was collected on the three most recent CS deliveries in the preceding 12 months at facilities with at least one CS delivery in the preceding three months. After excluding 16 facilities with no recent CS deliveries, the sample includes 173 CS deliveries at 62 facilities.</p> <p>Results</p> <p>No CS deliveries were performed in the previous three months at 21% of facilities surveyed; all of these were lower-level facilities. Most CS deliveries (88%) were classified as emergencies, and only 12% were referrals from another facility. General anesthesia was used in 62% of cases, and spinal or epidural anesthesia in 34%. Only 28% of cases were managed with a partograph. Surgery began less than one hour after the decision for a CS delivery in just 30% of emergency cases. Among the 173 cases, 27 maternal deaths, 28 stillbirths, and 3 early neonatal deaths were documented. In cases of maternal and fetal death, the most common indications for CS delivery were placenta praevia or abruption and malpresentation. In 62% of maternal deaths, the fetus was stillborn or died shortly after birth. In 48% of stillbirths, the fetus had a normal heart rate at the last check. Information on partograph use was missing in 38% of cases, information on parity missing in 23% of cases and indications for cesareans missing in 9%.</p> <p>Conclusions</p> <p>Timely referral within and to EmONC facilities would decrease the proportion of CS deliveries that develop to emergency status. While the substantial mortality associated with CS in Afghanistan may be partly due to women coming late for obstetric care, efforts to increase the availability and utilization of CS must also focus on improving the quality of care to reduce mortality. Key goals should be encouraging use of partographs and improving decision-making and documentation around CS deliveries.</p

Leadership Training in Undergraduate Medical Education: A Systematic Review

Background: This review seeks to characterize existing curricular interventions implemented to develop leadership skills in undergraduate medical students at LCME-accredited medical schools and elucidate best practices for leadership curriculum development. Methods: PRISMA guidelines were used to guide the review. Comprehensive literature searches of five databases retrieved peer-reviewed journal articles with empirical data published in English. Two phases of screening were conducted to identify studies describing leadership development curricular interventions, followed by data extraction and synthesis. Results: Comprehensive literature searching and hand searching identified 977 articles potentially eligible for inclusion, with a final set of 16 articles selected for the review. A majority of the leadership development programs targeted preclinical students, while others spanned the entire curriculum. "Mixed settings," including both classroom and clinical and community components were common. There was a wide range of cohort sizes spanning from over 100 students to fewer than 10. Using the competencies defined by Mangrulkar et al, we determined that all of the programs described leadership skills development, including conflict management and emotional intelligence. Out of the 16 selected studies, curricula that emphasized the development of skills were evidence-based medicine and practice, and 6 curricula targeted interprofessionalism. Conclusions: Leadership development needs to be standardized in undergraduate medical education, ideally using a competency-based framework to develop these standards. Longitudinal programs that had a didactic and project-based component received consistently high quality and effectiveness scores, as did programs with smaller cohort sizes that received more consistent mentorship and monetary investment from institutions

Electrode-induced lattice distortions in GaAs multi-quantum-dot arrays

Copyright © Materials Research Society 2019. Increasing the number of quantum bits while preserving precise control of their quantum electronic properties is a significant challenge in materials design for the development of semiconductor quantum computing devices. Semiconductor heterostructures can host multiple quantum dots that are electrostatically defined by voltages applied to an array of metallic nanoelectrodes. The structural distortion of multiple-quantum-dot devices due to elastic stress associated with the electrodes has been difficult to predict because of the large micrometer-scale overall sizes of the devices, the complex spatial arrangement of the electrodes, and the sensitive dependence of the magnitude and spatial variation of the stress on processing conditions. Synchrotron X-ray nanobeam Bragg diffraction studies of a GaAs/AlGaAs heterostructure reveal the magnitude and nanoscale variation of these distortions. Investigations of individual linear electrodes reveal lattice tilts consistent with a 28-MPa compressive residual stress in the electrodes. The angular magnitude of the tilts varies by up to 20% over distances of less than 200 nm along the length of the electrodes, consistent with heterogeneity in the metal residual stress. A similar variation of the crystal tilt is observed in multiple-quantum-dot devices, due to a combination of the variation of the stress and the complex electrode arrangement. The heterogeneity in particular can lead to significant challenges in the scaling of multiple-quantum-dot devices due to differences between the charging energies of dots and uncertainty in the potential energy landscape. Alternatively, if incorporated in design, stress presents a new degree of freedom in device fabrication