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We present the initial results from a program aimed at establishing a network of hot DA white dwarfs to serve as spectrophotometric standards for present and future wide-field surveys. These stars span the equatorial zone and are faint enough to be conveniently observed throughout the year with large-aperture telescopes. The spectra of these white dwarfs are analyzed in order to generate a non-local-thermodynamic-equilibrium model atmosphere normalized to Hubble Space Telescope colors, including adjustments for wavelength-dependent interstellar extinction. Once established, this standard star network will serve ground-based observatories in both hemispheres as well as space-based instrumentation from the UV to the near IR. We demonstrate the effectiveness of this concept and show how two different approaches to the problem using somewhat different assumptions produce equivalent results. We discuss the lessons learned and the resulting corrective actions applied to our program. [ABSTRACT FROM AUTHOR]

Cigarette smoking is considered to be a risk factor for several chronic diseases and even premature death. However, despite the importance of this detrimental habit, little seems known in terms of the overall toxicity potential of its ingredients in humans. In this study, a panel of genetically modified bioluminescent bioreporter bacteria was used to evaluate its usefulness in estimating the cigarette smoke's complex molecular mixture on a bacterial toxicity-bioreporter panel, both filtered or unfiltered. This work enabled to confirm the usefulness of cigarette filters, with better protection found in higher priced brands despite both having genotoxic and cytotoxic attributes. Quorum sensing interference was also shown, which may explain why cigarette smokers are at greater risk for pulmonary infections. Moreover, the findings of this study support the fact that the filter is a dominating contributor to reducing the harm caused by cigarette smoke. Increased efforts should be conducted to reduce the harmful effects of cigarette smoke, via increasingly effective filters. To conclude, the panel of bioreporter bacteria was found to be useful in the evaluation of the general effect of the toxic mixture found in cigarette smoke and therefore has the potential to be used in cigarette research, helping researchers pinpoint the reduction of toxicity when working with filter improvement., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: The COVID-19 pandemic is a demonstration of an unforeseen event that disrupts normal life routine and greatly affects medical training. With its outbreak, clinical studies in medical schools were discontinued throughout the country, and the pre-clinical studies channeled into online learning, like all other university teaching activities. Since similar situations occurred in most western countries, a methodological approach of online teaching is required - principles, goals and implementation, with reference to the tension between the duty of care versus the duty of maintaining the clinician's and student's health. In this paper we will present the dilemmas faced by the various medical education institutions in the world, along with the ways of coping and the experience gained from similar situations - including in Israel. We will discuss the techno-pedagogical principles that are at the heart of online teaching, demonstrate the experience gained in Israel and around the world, and offer a framework for comprehensive discussion for situations that threaten medical education learners. Finally, we will provide a list of online teaching resources for clinical teaching (that are mostly free and can be readily used by medical education faculties).

The lateral flow immunoassay (LFIA) is the most successful point-of-care testing (POCT) method to date. In the case of clinical biomarkers that require quantification, it remains a challenge to quantitate those biomarkers using the lateral flow immunoassay remains a challenge due to the cost of the reader and possibly the type of marker used. In the present work, a new concept of a platform LFIA device configuration is proposed in which different, aligned membrane components, some already existing in the classical lateral flow immunoassay, and the others created with special new functions in the present device. As the sample containing the target analyte passes through the aforementioned membranes, the target analyte will initially interact with a target-specific antibody-conjugated to horseradish peroxidase (HRP). Thereafter, the newly formed immunocomplex will diffuse through a proprietary capture membrane (that ensures that the nontarget-bound antibodies do not continue further and thus remain "captured" to that specific area). This is done by having the target molecules (or components thereof) immobilized onto the said capture layer. The target-bound immunocomplexes will then be allowed by the system configuration to continue further to the last layer, where the signal will be generated and quantified. Thus, in the absence of the target analyte in the sample, the free antibodies will be filtered at the capture layer by preimmobilized analyte molecules, thus preventing a false positive signal to occur. We validated the concept in the detection of dengue NS1 protein in view of making a triage test. The sample containing NS1 will first meet HRP-conjugated NS1-specific antibodies and become attached, thus producing an NS1-specific antibody-HRP immunocomplex. The sample then flows through the blocking layer, where the immunocomplex is unchallenged and thus allowed to reach the last "absorbent" pad, incorporating the substrate for the HRP marker. In the case of a positive test, a signal is generated, that is proportional to the amount of immunocomplexes (and therefore the NS1 concentration), and then analyzed and measured at the absorbent pad. Any unbound anti-NS1 antibody will be stopped at the blocking matrix by preimmobilized NS1, so there will be no false positive. As this study is the initial study of a novel configuration, much of the work comprised of optimization steps, such as determining the required NS1 membrane-immobilization concentration and the required target-specific capture antibody concentration. Our immunoassay was tested with spiked buffer and serum samples to mimic the clinical conditions, with a range of NS1 concentrations, and was found, at this time, to be fivefold more sensitive than a gold standard enzyme-linked immunosorbent assay (ELISA) test (5 ng mL -1 ) performed in our laboratory. This method shows another form of LFIA that has the potential to be quantitative (at least semiquantitative), albeit not solving the reader cost; however, unlike the regular LFIA, we do not use nanobeads but instead enzymes, allowing, in theory, greater sensitivity, while retaining the one-step procedure. The test is accurate and has low production costs., Competing Interests: The authors declare the following competing financial interest(s): The authors all declare that they do not have any conflicts of interest to declare, including financial, non-financial interests, relationships, direct employment nor stock ownership with a private sector entity connected to the present study, intellectual property or honoraria. The present study does form part of a patent filed in the name of two of the authors (TA, RM) in the ownership of their institution, including a third-party patent (PCT/SG2016/050578) (EE, RM)., (Copyright © 2020 American Chemical Society.)

Background: Proper glenoid position in total shoulder arthroplasty (TSA) is important. However, traditional glenoid version (GV) measurements overestimate retroversion on radiographs (XR) and computed tomography (CT).The fulcrum axis (FA) uses palpable surface landmarks and may be useful as an intra-operative guide. Also, the FA has not yet been validated on XR or CT in an arthritic population., Methods: Four observers measured FA and GV on the XR, CT and three-dimensional CT (3DCT) of 40 patients who underwent TSA at a single institution from 2009 to 2015. Reliability and accuracy of FA and GV were calculated for XR and CT, using 3DCT as the gold standard., Results: The mean FA and GV were 7.768° and 18.910° on XR; 6.23° and 12.920° on CT; and 8.100° and 7.740° on 3DCT, respectively. FA and GV were significantly different for XR and CT ( p  < 0.001) but not for 3DCT ( p  = 0.725). The inter-rater reliability, intra-rater reliability and accuracy of FA were not significantly different from GV and were 0.929 to 0.948, 0.779 to 0.974 and 0.674 to 0.705, respectively. However, the absolute difference of FA was closer to the gold standard (3DCT) than GV for XR (0.330° versus 11.172°) and CT (1.871° versus 5.178°) ( p  < 0.001)., Conclusions: FA showed comparable reliability and accuracy to GV. However, FA more accurately reflected the gold standard.

Integrating a dissolvable membrane into a sensor allows the control of sample flow, location and duration in critical areas. These time-barrier films stop the flow of samples until the membrane has dissolved, thus, for example, allowing increased exposure time between immunoreagents for the formation of greater numbers of immuno-complexes, ensuring higher sensitivity, reactivity, and helping to reduce false-positive signals. In this study, dissolvable polyvinyl alcohol (PVA) films are used in a 3D-printed sensor holder, which enables film integration without the use of glue. PVA is a synthetic hydrophilic linear polymer, its solubility is dependent on its molecular weight and degree of hydrolysis. Three types of PVAs films were tested herein: (1) PVA 1-Mw: 30⁻70 K, 87⁻90% hydrolyzed; (2) PVA 2-Mw: 31⁻50 K, 98⁻99% hydrolyzed and (3) PVA 3-Mw: 89⁻98 K, >99% hydrolyzed. The films were exposed to water in (1) the novel 3D-printed holder and (2) directly immersed into a water droplet. After comparing the time taken to dissolve PVA 1⁻3 films, PVA 1 films of 5⁻20% (w/v) are found to be most suitable as time barrier films, due to their optimal dissolution times and physical properties for integration into the customized 3D-printed holder.

Background: By 2020, the World Health Organization predicts that two-thirds of all diseases worldwide will be the result of lifestyle choices. Physicians often do not counsel patients about healthy behaviors, and lack of training has been identified as one of the barriers. Between 2010 and 2014, Hebrew University developed and implemented a 58-h Lifestyle Medicine curriculum spanning five of the 6 years of medical school. Content includes nutrition, exercise, smoking cessation, and behavior change, as well as health coaching practice with friends/relatives (preclinical years) and patients (clinical years). This report describes this development and diffusion process, and it also presents findings related to the level of acceptance of this student-initiated Lifestyle Medicine (LM) curriculum., Methods: Students completed an online semi-structured questionnaire after the first coaching session (coaching questionnaire) and the last coaching session (follow-up questionnaire)., Results: Nine hundred and twenty-three students completed the coaching questionnaire (296 practices were with patients, 627 with friends /relatives); and 784 students completed the follow-up questionnaire (208 practices were with patients, 576 with friends /relatives). They reported overall that health coaching domains included smoking cessation (263 students), nutrition (79), and exercise (117); 464 students reported on combined topics. Students consistently described a high acceptance of the curriculum and their active role in coaching. Further, most students reported that they were eager to address their own health behaviors., Conclusions: We described the development and acceptance of a student-initiated comprehensive LM curriculum. Students perceived LM as an important component of physicians' professional role and were ready to explore it both as coaches and in their personal lives. Thus, medical school deans might consider developing similar initiatives in order to position medical schools as key players within a preventive strategy in healthcare policy.

How black holes accrete surrounding matter is a fundamental yet unsolved question in astrophysics. It is generally believed that matter is absorbed into black holes via accretion disks, the state of which depends primarily on the mass-accretion rate. When this rate approaches the critical rate (the Eddington limit), thermal instability is supposed to occur in the inner disk, causing repetitive patterns of large-amplitude X-ray variability (oscillations) on timescales of minutes to hours. In fact, such oscillations have been observed only in sources with a high mass-accretion rate, such as GRS 1915+105 (refs 2, 3). These large-amplitude, relatively slow timescale, phenomena are thought to have physical origins distinct from those of X-ray or optical variations with small amplitudes and fast timescales (less than about 10 seconds) often observed in other black-hole binaries-for example, XTE J1118+480 (ref. 4) and GX 339-4 (ref. 5). Here we report an extensive multi-colour optical photometric data set of V404 Cygni, an X-ray transient source containing a black hole of nine solar masses (and a companion star) at a distance of 2.4 kiloparsecs (ref. 8). Our data show that optical oscillations on timescales of 100 seconds to 2.5 hours can occur at mass-accretion rates more than ten times lower than previously thought. This suggests that the accretion rate is not the critical parameter for inducing inner-disk instabilities. Instead, we propose that a long orbital period is a key condition for these large-amplitude oscillations, because the outer part of the large disk in binaries with long orbital periods will have surface densities too low to maintain sustained mass accretion to the inner part of the disk. The lack of sustained accretion--not the actual rate--would then be the critical factor causing large-amplitude oscillations in long-period systems.

Toxicants in water sources are of concern. We developed a tool that is affordable and easy-to-use for monitoring toxicity in water. It is a biosensor composed of disposable bioreporter pads (calcium alginate matrix with immobilized bacteria) and a non-disposable CMOS photodetector. Various parameters to enhance the sensor's signal have been tested, including the effect of alginate and bacterium concentrations. The effect of various toxicants, as well as, environmental samples were tested by evaluating their effect on bacterial luminescence. This is the first step in the creation of a sensitive and simple operative tool that may be used in different environments., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Case: A twenty-two-year-old male patient presented to our trauma center after a motor-vehicle accident in which he sustained multiple injuries, including a volar dislocation of the hamate and ipsilateral scapholunate dissociation. Following closed reduction of the hamate dislocation, open reduction and stabilization of these carpal injuries was undertaken two days post-injury via a dorsal approach. Percutaneous Kirschner wires were used as well as two mini suture anchors to repair the scapholunate ligament. The patient was immobilized for six weeks and Kirschner wires were removed at twelve weeks postoperatively., Conclusion: To our knowledge, hamate dislocation with scapholunate dissociation and its surgical treatment have not previously been described. Successful surgical treatment for this injury pattern may be performed dorsally via direct reduction and repair of the scapholunate ligament with percutaneous pinning of the affected carpal bones.

A 17-year-old adolescent boy presented with progressive lower back pain and fatigue., (Copyright 2015, SLACK Incorporated.)

Acute compartment syndrome is a surgical emergency and its diagnosis is more difficult in obtunded or insensate patients. We present the case of a 34-year-old woman who sustained a Gustilo-Anderson grade III open midshaft femur fracture with an isolated femoral vein injury treated with direct repair. She developed lower leg compartment syndrome at 48 hours postoperatively, necessitating fasciotomies. She was subsequently found to have a DVT in her femoral vein at the level of the repair and was started on therapeutic anticoagulation. This case highlights the importance of recognition of isolated venous injuries in a trauma setting as a risk factor for developing compartment syndrome.

Background: This prospective longitudinal study compared clinical and radiologic outcomes of total shoulder arthroplasty (TSA) using 3 different prosthetic designs, the Neer II system, the Bigliani-Flatow (BF), and a stemless prosthesis, the Total Evolutive Shoulder System (TESS)., Materials and Methods: Patients with advanced osteoarthritis of the glenohumeral joint who underwent TSA were followed up for 2 years. Four patient-oriented disability outcomes were used. The clinical data collected before surgery and at follow-up assessments during a 2-year period included active range of motion (ROM) in 6 directions and strength. Radiographic signs of glenoid and humeral component loosening were recorded. The incidence of humeral head subluxation was documented., Results: Seventy-four patients completed the study. There was a significant improvement in the 4 disability measures, ROM, and strength at 2 years in all 3 groups (P < .0001). Active external rotation at 90° abduction was statistically significantly lower in the Neer II group (P = .001). The incidence of lucent lines around the glenoid component was higher in the Neer II group (P = .0002). No statistically significant relationship was seen between type of prosthesis and patient satisfaction (P > 0.05)., Conclusions: The 3 types of TSA prostheses used in this study all provided significant improvement in pain and function and were associated with high patient satisfaction. The Neer II was associated with less active external rotation and more lucent lines., (Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.)

Surgery may be indicated in treating Madelung's deformity and numerous techniques have been described. This study reports the early clinical and radiological results of a radial biplanar opening wedge osteotomy and modified Darrach procedure, using the excised ulnar head as a trapezoidal bone graft. Between 2000 and 2008, five adult wrists with symptomatic Madelung's deformity underwent surgery. All patients were female, with an average age at surgery of 34 years. Assessment included range of movement, grip strength, DASH scores and radiological imaging. All patients improved both subjectively and objectively with regards to pain, functional range of movement, and appearance at mean follow-up of 55 months (range 14-113). All osteotomies united. One patient required removal of hardware for restricted rotation. This technique provided satisfactory results that are comparable to other studies, and avoids the use of iliac crest bone graft.

Purpose: Shoulder pain is a major musculoskeletal and economic concern in industrialized countries, with the rate of surgical failure reportedly higher in patients injured at work. The purposes of this study were (1) to examine the prevalence of identifiable causes of rotator cuff surgery failure and (2) to examine the relationship among the existence of these causes and outcome scores, patient expectations, and overall satisfaction., Methods: This was a cross-sectional study of patients who experienced continued impairments following surgical treatment for work-related injuries. The primary outcome was a disease-specific measure, the Western Ontario Rotator Cuff (WORC) index. Patients were categorized into two groups based on the existence of an identifiable reason for surgical failure vs. no reason for failure, as demonstrated by clinical and radiologic investigations and decided upon by a shoulder surgeon and a physical therapist. Analyses included a t-test for independent sample means, linear regression, non-parametric Wilcoxon test, and Fisher's exact test., Results: Thirty-eight consecutive patients were included in the study, and 24 causes of surgical failure were identified in 19 patients (50%). Overall, patients with findings of failure were more disabled according to the total WORC index and had higher levels of symptoms, emotional difficulties, and limitations in sports and recreational activities. Expectations and satisfaction levels were not significantly different between groups., Conclusion: Our results indicate that 50% of patients who reported failed surgery had at least one reason to explain their ongoing symptoms, emotional difficulties, and functional limitations.

A high-temporal resolution collection technique was applied to refine aerosol sampling in Jerusalem, Israel. Using stable lead isotopes, lead concentrations, synoptic data, and atmospheric modeling, we demonstrate that lead detected in the atmosphere of Jerusalem is not only anthropogenic lead of local origin but also lead emitted in other countries. Fifty-seven percent of the collected samples contained a nontrivial fraction of foreign atmospheric lead and had 206Pb/207Pb values which deviated from the local petrol-lead value (206Pb/207Pb = 1.113) by more than two standard deviations (0.016). Foreign 206Pb/207Pb values were recorded in Jerusalem on several occasions. The synoptic conditions on these dates and reported values of the isotopic composition of lead emitted in various countries around Israel suggest that the foreign lead was transported to Jerusalem from Egypt, Turkey, and East Europe. The average concentration of foreign atmospheric lead in Jerusalem was 23 +/- 17 ng/m3, similar to the average concentration of local atmospheric lead, 21 +/- 18 ng/ m3. Hence, the load of foreign atmospheric lead is similar to the load of local atmospheric lead in Jerusalem.

Clinical and radiographic assessment of the results of 40 Swanson silicone ulnar head prosthesis implants in three different patient groups is presented. Twenty-eight were done for treatment of rheumatoid arthritis, eight for ulnoradial impingement after the Darrach procedure, and four for ulnocarpal impingement resulting from malunited Colles' fractures. Patients were reviewed 12 to 48 months after operation (mean, 29 months). Seventy-eight percent of patients reported relief of pain and improved function. Radiologic examination showed that all patients exhibited resorption of the distal ulna (mean 4.4 mm) and that resorption was worst in the group with rheumatoid arthritis. Bone resorption about the implant predisposed the cap to both side-to-side tilt and pistoning of the prosthesis on supination and pronation. There was a 10% revision rate because of silicone synovitis. Although clinical results remain satisfactory for patients with rheumatoid arthritis and ulnocarpal impingement, the radiologic results suggest that Swanson ulnar head replacement should be restricted to elderly patients with rheumatoid arthritis.

Male rats were injected with 5, 10, and 20 mg diphenylhydantoin daily for two months and then caged for five days with cyclic females. Thereafter the males underwent necropsy, the organs of the genital tract were examined, and found to be unaffected. Blood testosterone and Leydig cell counts were normal. A significant reduction of fertility was observed which appears to be loss of libido on behavioural grounds. Except for similar behavioural changes described in human epileptics no further reports are available concerning anticonvulsants and fertility. Our findings indicate that there is no reason to suspect that diphenylhydantoin had endocrine-mediated effects on male fertility in the rat.

Malunions of distal radius fractures are commonplace. Patients are decreasingly willing to accept the disability that may be associated with them. While the first line of treatment is initial good fracture care, corrective osteotomies offer later opportunity for pain relief and improved function.

Intra-articular incongruity of the distal radius at the radiocarpal joint is a bad prognostic feature; reduction by closed or open operative techniques is important. However, both techniques have limitations. We describe a new technique of reduction of the lunate facet under radiographic control, with very limited operative exposure and tissue trauma. In two cases anatomic restoration of the radiocarpal joint was obtained by this technique and maintained with external and limited internal fixation. Follow-up results are very encouraging. Currently we suggest use of this simple technique when faced with an incongruous radiocarpal joint after unsatisfactory attempts at closed reduction.

Antigen presenting cells may have a direct bearing on the results of allotransplantation of bone. There is no doubt that these cells are neither T nor B lymphocytes and that they do reside in the bone marrow. Evidence suggests that these bone marrow cells are of the granulocyte lineage and that they initiate immunologic reactions in vitro. The removal of bone marrow that contains these cells from bone allografts would decrease the immunologic response to the implantation of such transplants.