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Carbon fibers passing current are subject to resistive heating. When failure occurs, this is related to their local temperature. The failure temperature and its location are estimated. The temperature variation is calculated using analytical models for electrical and thermal conductivities based on the temperature dependent electron–phonon relaxation time. In the absence of radiative heat loss, an analytic expression of temperature along the fiber is given from which a maximum possible emission current is derived and is governed by a single introduced parameter ω o. A method of treating the radiative heat loss is developed and is governed by a second parameter γ , which allows a rapid numerical means to calculate the correction to the analytic form. Heat variation along a thick carbon fiber is contrasted to that along a multi-walled carbon nanotube (MWNT): it is shown that the relative magnitude of ω o compared to γ determines that the analytical formula is a good approximation for MWNTs but requires numerical correction for fibers. Furthermore, it is shown that the analytical form of ω o specified a maximum current beyond which the carbon emitter fails due to thermal runaway. The theoretical models are used to interpret observed behavior of field emission from carbon fibers and the resulting damage they endure when the extracted field-emission current is high. Results from implementing the developed temperature variation model into the MICHELLE beam optics simulation code are presented, with an example application predicting the conditions for stable equilibrium operation as well as for the onset of fiber failure. [ABSTRACT FROM AUTHOR]

A methodology of modeling nonplanar surfaces, in which the microscale features of the emission sites can be orders of magnitude smaller than the mesoscale features defining the active emission area, has been developed and applied to both ordered arrays of identical emitters and random variations characteristic of a roughened surface. The methodology combines a general thermal-field-photoemission model for electron emission, a point charge model for the evaluation of field enhancement factors and surface geometry, and a Ballistic-Impulse model to account for the trajectories of electrons close to the cathode surface. How microscale and mesoscale features can both undermine the estimation of thermal-field emission parameters, such as characteristic field enhancement and total current predictions, as well as give rise to changes in the distribution of transverse velocity components used to estimate beam quality features such as emittance that are important to photocathodes, is quantified. The methodology is designed to enable both the proper characterization of emitters based on experimental current-voltage data and the development of a unit cell model of emission regions that will ease the emission model demands in beam optics codes. [ABSTRACT FROM AUTHOR]

Interpreting the Dataset The dataset was prepared by merging the main survey dataset with the diary survey dataset in IBM SPSS Statistics using respondents' unique ID, limiting the subsample to only those who contributed at least one diary survey entry. Using the Dataset The diary survey dataset described in this paper provides valuable information about the development of public perspectives and behaviors over the course of nearly one year during the COVID-19 pandemic. Following their first completed diary survey stage, reminders for the next survey stages were sent in two-week intervals from the time they completed their last diary survey stage. Keywords: COVID-19; vaccination; conspiracy theories; risk perception; information behavior EN COVID-19 vaccination conspiracy theories risk perception information behavior 1 4 4 05/05/22 20220502 NES 220502 Introduction Many psychological, sociological and communication challenges have emerged or become attenuated during the COVID-19 pandemic. [Extracted from the article]

Taking place annually in more than 400 cities, European Researchers' Night is a pan- European synchronized event that aims to bring researchers closer to the public. In this paper audience profiles are compared from events in 2019 and 2020. In 2019, face-to-face events reached an estimated 1.6 million attendees, while in 2020, events shifted online due to the COVID-19 pandemic and reached an estimated 2.3 million attendees. Focusing on social inclusion metrics, survey data is analyzed across two national contexts (Ireland and Malta) in 2019 (n = 656) and 2020 (n = 506). The results from this exploratory, descriptive study shed light on how moving public engagement with research online shifted audience profiles. Based on prior research about the digital divide in access and use of online media, hypotheses were proposed that online European Researchers' Night events would attract audiences with higher educational attainment levels and greater self-reported, subjective economic well-being. While changes were observed from 2019 to 2020, results for each hypothesis show a mixed picture. The first hypothesis was upheld for the highest education levels but failed for the lowest levels suggesting that the pivot to online events simultaneously attracted participants with no formal education and those with postgraduate qualifications, while attracting less of those with undergraduate or lower levels of education. The second hypothesis was not upheld, with online European Researchers' Night events attracting audiences with slightly higher levels of economic well-being compared to face-to-face events. The findings of this study indicate that European Researchers' Night events present a clear opportunity to measure the effects of the digital divide in relation to public engagement with research across Europe. [ABSTRACT FROM AUTHOR]

European Researchers' Night is an annual pan-European synchronized event devoted to public engagement with research. It was first held in 2005 and now occurs in over 400 cities across Europe, with the aim of bringing researchers closer to the general public. To investigate social inclusion in these events, we conducted survey research across three national contexts (Ireland, Malta and the UK) and events in seven cities between 2016 and 2019 (n = 1590). The results from this exploratory descriptive study confirmed one hypothesis, namely that event attendees had substantially higher levels of university qualification than the national publics. This is in line with wider patterns of unequal participation in public engagement with research activities based on socio-economic status. However, we also found mixed evidence on the prevalence of ethnic minority representation among event attendees compared to the general population, thus failing to uphold the second hypothesis that predicted an over-representation of white majority participants. This second finding diverges from existing research findings about ethnic diversity amongst science communication audiences, raising the possibility that some public engagement events are over-performing on this dimension of social inclusion. Overall, the findings demonstrate that European Researchers' Night has potential for addressing the critical goal of enhancing the diversity of audiences for public engagement with research, even as it falls short on the key metric of socio-economic diversity. [ABSTRACT FROM AUTHOR]

A model of a thermionic cathode in a planar diode in which the Poisson and Vlasov equations are solved in 3-D assuming an infinite magnetic field is presented. We explore how 2-D work function variations across the cathode surface may affect the transition between temperature-limited and space-charge-limited flow, commonly known as the “knee” of the Miram curve. We study a variety of work function distributions, both realistic and idealized, and demonstrate how emission from the lowest work function regions dominates the total anode current even when such regions make up a relatively small fraction of cathode area. Our model also illustrates the ability of cathodes to reach the full Child–Langmuir current despite the presence of a sizeable nonemitting region. We find that as the length scale of these work function variations decreases, the Miram knee grows sharper, indicating improved cathode performance. [ABSTRACT FROM AUTHOR]

This article discusses the linguistic issues which are involved in the interpretation of Rev 20:4–5. It demonstrates that the aorist tense-form of ἔζησαν in v. 4 neither necessarily nor even likely here results in the inchoative reading favored by premillennialist interpreters. It also provides two readings of v. 5 which fit naturally with a non-inchoative reading. [ABSTRACT FROM AUTHOR]

Purpose: Current guidelines for computed tomography (CT) after blunt trauma were developed to capture all intra-abdominal injuries (IAI). We hypothesize that current AST/ALT guidelines are too low leading to unnecessary CT scans for children after blunt abdominal trauma (BAT).Methods: Patients who received CT of the abdomen after blunt trauma at our Level I Pediatric Trauma Center were stratified into a high risk (HR) (liver/spleen/kidney grade ≥III, hollow viscous, or pancreatic injuries) and low risk (LR) (liver/kidney/spleen injuries grade ≤II, or no IAI) groups.Results: 247 patients were included. Of the 18 patients in the HR group, two required surgery (splenectomy and sigmoidectomy). Transfusion was required in 30% of grade III and 50% of grade IV injuries. Eleven (5%) patients in LR group were transfused for indications other than IAI, and none were explored surgically. Both AST (r = 0.44, p < 0.001) and ALT (r = 0.43, p < 0.001) correlated with grade of liver injury. Using an increased threshold of AST/ALT, 400/200 had a negative predictive value of 96% in predicting the presence of HR liver injuries.Conclusion: The current cutoff of liver enzymes leads to over-identification of LR injuries. Consideration should be given to an approach that aims to utilize CT in pediatric BAT that identifies clinically HR injury. [ABSTRACT FROM AUTHOR]

While it has recently become a common assumption that the traditional understanding of the grammar of John 3.16 ('For God so loved the world that ...') is misleading or simply inaccurate, this article demonstrates on the basis of parallel constructions from the ancient Greek corpus that οὕτως ... ὥστε, when used with ἀγαπάω, functions as a correlative intensifier–result pair, exactly as it is presented in the traditional understanding. [ABSTRACT FROM AUTHOR]

Axonopathy is a hallmark of many neurodegenerative diseases including glaucoma, where elevated intraocular pressure (ocular hypertension, OHT) stresses retinal ganglion cell (RGC) axons as they exit the eye and form the optic nerve. OHT causes early changes in the optic nerve such as axon atrophy, transport inhibition, and gliosis. Importantly, many of these changes appear to occur prior to irreversible neuronal loss, making them promising points for early diagnosis of glaucoma. It is unknown whether OHT has similarly early effects on the function of RGC output to the brain. To test this possibility, we elevated eye pressure in mice by anterior chamber injection of polystyrene microbeads. Five weeks post-injection, bead-injected eyes showed a modest RGC loss in the peripheral retina, as evidenced by RBPMS antibody staining. Additionally, we observed reduced dendritic complexity and lower spontaneous spike rate of On-αRGCs, targeted for patch clamp recording and dye filling using a Opn4 -Cre reporter mouse line. To determine the influence of OHT on retinal projections to the brain, we expressed Channelrhodopsin-2 (ChR2) in melanopsin-expressing RGCs by crossing the Opn4 -Cre mouse line with a ChR2-reporter mouse line and recorded post-synaptic responses in thalamocortical relay neurons in the dorsal lateral geniculate nucleus (dLGN) of the thalamus evoked by stimulation with 460 nm light. The use of a Opn4 -Cre reporter system allowed for expression of ChR2 in a narrow subset of RGCs responsible for image-forming vision in mice. Five weeks following OHT induction, paired pulse and high-frequency stimulus train experiments revealed that presynaptic vesicle release probability at retinogeniculate synapses was elevated. Additionally, miniature synaptic current frequency was slightly reduced in brain slices from OHT mice and proximal dendrites of post-synaptic dLGN relay neurons, assessed using a Sholl analysis, showed a reduced complexity. Strikingly, these changes occurred prior to major loss of RGCs labeled with the Opn4 -Cre mouse, as indicated by immunofluorescence staining of ChR2-expressing retinal neurons. Thus, OHT leads to pre- and post-synaptic functional and structural changes at retinogeniculate synapses. Along with RGC dendritic remodeling and optic nerve transport changes, these retinogeniculate synaptic changes are among the earliest signs of glaucoma. [ABSTRACT FROM AUTHOR]

Purpose: Simulation-based training has the potential to improve team-based care. We hypothesized that implementation of an in situ multidisciplinary simulation-based training program would improve provider confidence in team-based management of severely injured pediatric trauma patients.Methods: An in situ multidisciplinary pediatric trauma simulation-based training program with structured debriefing was implemented at a free-standing children's hospital. Trauma providers were anonymously surveyed 1 month before (pre-), 1 month after (post-), and 2 years after implementation.Results: Survey response rate was 49% (n = 93/190) pre-simulation, 22% (n = 42/190) post-simulation, and 79% (n = 150/190) at 2-year follow-up. These providers reported more anxiety (p = 0.01) and less confidence (p = 0.02) 1-month post-simulation. At 2-year follow-up, trained providers reported less anxiety (p = 0.02) and greater confidence (p = 0.01), compared to untrained providers.Conclusions: Implementation of an in situ multidisciplinary pediatric trauma simulation-based training program may initially lead to increased anxiety, but long-term exposure may lead to greater confidence.Level Of Evidence: II, Prospective cohort. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether falls from significant height occur more frequently in young children. We conducted a 10-year (2004-2014), comparative study using a retrospective cohort of 4713 children (< 18 years) from the Los Angeles county trauma database who were evaluated for a fall. Exposure was fall height, dichotomized into < 10 ft/low-risk fall and > 10 ft/high-risk fall. Primary outcome was age of fall. Secondary outcomes were disposition from emergency department, injuries, resource utilization, and mortality. Of all falls, 4481 (95%) were low-risk and 232 (5%) high-risk. High-risk falls were more frequent in children 1-3 years old (58 vs. 30%, p < 0.01), associated with higher frequency of intracranial hemorrhage (19 vs. 10%, p < 0.01), intubation (11 vs. 1%, p < 0.01), and neurosurgical procedure (2 vs. 0.8%, p = 0.04). There was no difference in mortality (0.86 vs. 0.13%, p = 0.06). In Los Angeles County, children 1-3 years old are most likely to suffer high-risk falls, which are associated with serious injury. Integration of fall prevention education into routine anticipatory guidance should be strongly considered for children 1-3 years old. [ABSTRACT FROM AUTHOR]

Cell phone use has been implicated in driver distraction and motor vehicle crashes, and more recently has been associated with distracted pedestrians. There are limited data on interventions aimed at this important public health issue. We hypothesized that the use of a visual intervention near street crossings would decrease the frequency of distracted behaviors of pedestrians. We performed a prospective observational cohort study examining painted sidewalk stencils reading, “Heads Up, Phones Down” as an intervention to decrease cell phone distractions amongst pedestrians. These stenciled messages were placed at a children’s hospital, middle school, and high school in Los Angeles County. Anonymous observations of pedestrian distractions (texting, talking on a phone, headphone use, and other) were conducted before, 1 week after, and 4 months after the intervention. Distractions were compared before and after intervention using Chi square tests. A total of 11,533 pedestrians were observed, with 71% children and 29% adults. Total distractions decreased from 23% pre-intervention to 17% 1 week after stencil placement (p < 0.01), but this was not sustained at 4 months (23%, p = 0.4). A sustained decrease was observed only for texting at 4 months post-intervention (8.5% vs. 6.8%, p < 0.01). A simple visual intervention reduced distracted cell phone usage in pedestrians crossing the street, but this was most effective early after the intervention. Future studies are warranted to determine how to sustain this effect over time and how to minimize other types of distractions. [ABSTRACT FROM AUTHOR]

Considering the lexical possibilities inherent within עַיןִ, this article proposes that the reference to "Leah's eyes" in Genesis 29:17 speaks not of her eyes but of her general appearance. [ABSTRACT FROM AUTHOR]

Background: A new type of influenza virus, known as type D, has recently been identified in cattle and pigs. Influenza D virus infection in cattle is typically asymptomatic; however, its infection in swine can result in clinical disease. Swine can also be infected with all other types of influenza viruses, namely A, B, and C. Consequently, swine can serve as a “mixing vessel” for highly pathogenic influenza viruses, including those with zoonotic potential. Currently, the only antiviral drug available targets influenza M2 protein ion channel is not completely effective. Thus, it is necessary to develop an M2 ion channel blocker capable of suppressing the induction of resistance to the genetic shift. To provide a basis for developing novel ion channel-blocking compounds, we investigated the properties of influenza D virus M2 protein (DM2) as a drug target. Results: To test the ion channel activity of DM2, the DNA corresponding to DM2 with cMyc-tag conjugated to its carboxyl end was cloned into the shuttle vector pNCB1. The mRNA of the DM2–cMyc gene was synthesized and injected into Xenopus oocytes. The translation products of DM2–cMyc mRNA were confirmed by immunofluorescence and mass spectrometry analyses. The DM2–cMyc mRNA-injected oocytes were subjected to the two-electrode voltage-clamp (TEVC) method, and the induced inward current was observed. The midpoint (Vmid) values in Boltzmann modeling for oocytes injected with DM2–cMyc RNA or a buffer were −152 and −200 mV, respectively. Assuming the same expression level in the Xenopus oocytes, DM2 without tag and influenza C virus M2 protein (CM2) were subjected to the TEVC method. DM2 exhibited ion channel activity under the condition that CM2 ion channel activity was reproduced. The gating voltages represented by Vmid for CM2 and DM2 were –141 and –146 mV, respectively. The reversal potentials observed in ND96 for CM2 and DM2 were −21 and −22 mV, respectively. Compared with intact DM2, DM2 variants with mutation in the YxxxK motif, namely Y72A and K76A DM2, showed lower Vmid values while showing no change in reversal potential. Conclusion: The M2 protein from newly isolated influenza D virus showed ion channel activity similar to that of CM2. The gating voltage was shown to be affected by the YxxxK motif and by the hydrophobicity and bulkiness of the carboxyl end of the molecule. [ABSTRACT FROM AUTHOR]

Depressed collectors have been utilized successfully for many years to improve the electrical efficiency of vacuum electron devices. Increasingly, pulsed, high-peak power accelerator applications are placing a premium on electrical efficiency. As RF systems are responsible for a large percentage of the overall energy usage at accelerator laboratories, methods to improve upon the state-of-the-art in pulsed high-power sources are desired. This paper presents a technique for self-biasing the stages in a multistage depressed collector. With this technique, the energy lost during the rise and fall times of the pulse can be recovered, separate power supplies are not needed, and existing modulators can be retrofitted. Calculations show that significant cost savings can be realized with the implementation of this device in high-power systems. In this paper, the technique is described along with experimental demonstration. [ABSTRACT FROM AUTHOR]

AJDISK is a 1-D large signal klystron simulator developed at Stanford Linear Accelerator Center. A brief discussion of AJDISK's simulation algorithm is given and fully developed to show how AJDISK was extended to enable sheet beam klystron simulations. The primary requirement for extending disk simulators to sheet beam simulators is a space charge equation. Therefore, the electric field due to an infinitely thin plate of charge (infinitely thin in the direction of propagation) in a rectangular drift tube is derived. The derivation is extended to a 2-D space charge equation in which the plate is split into a series of rods with varying positions in $y$ . The derived equations are compared with the numerical simulations and measurement. [ABSTRACT FROM AUTHOR]

Kosmahl and Branch's derivation for the electric field in a round beam gap is closely followed to derive the electric field for a sheet beam klystron gap. The wider of the two transverse dimensions of the gap is taken to be infinite in extent and the field is derived based on an approximation of the gap field at the drift tube edge. The electric field equations are generalized using a Fourier series representation of the gap field at the drift tube edge. The analytical results are compared with the numerical computations. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic repair of congenital duodenal obstruction has become popularized over the past decade. Comparative data on outcomes, however, are sparse. We hypothesized that laparoscopic repair of congenital duodenal obstruction could be performed with similar outcomes to traditional open repair. Patients and Methods: Medical records for all cases of congenital duodenal obstruction from 2005 to 2011 at three academic teaching hospitals were retrospectively reviewed. Patients were excluded from the analysis if they had confounding surgical diseases, did not have duodenoduodenostomy during the first hospital admission, had the repair performed before transfer from a referring hospital, or weighed less than 1.7 kg at the time of surgery. Analysis was performed as intention to treat, with laparoscopic converted to open cases included in the laparoscopic group. Results: Sixty-four cases were included in the analysis (44 open, 20 laparoscopic). Baseline characteristics were similar between the two groups with the exception that the open group, on average, underwent repair later than the laparoscopic group (6 days versus 4 days, respectively). Seven laparoscopic cases were converted to an open procedure (35%), most commonly for difficulty in exposing the decompressed distal duodenum. Laparoscopic repair did take significantly longer than open repair (145 minutes versus 96 minutes, respectively), but clinical outcomes were similar. Complications were rare and were similar between methods of repair. Two patients in the laparoscopic group required subsequent open revision. Conclusions: Laparoscopic duodenoduodenostomy for congenital duodenal obstruction is a technically challenging procedure with a steep learning curve. Despite a relatively high conversion rate, clinical outcomes remained similar to the traditional open repair in selected patients. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the impact of the use of a bedsideplaced spring-loaded silo (SLS) on practice patterns and on outcomes for infants with gastroschisis. Design: Retrospective review comparing neonates with gastroschisis treated before and after the implementation of selective SLS placement. Setting: Tertiary referral center. Patients: Of 91 consecutive neonates admitted for initial treatment of gastroschisis between January 1998 and August 2007, 45 were admitted before and 46 were admitted after implementation of the SLS. Main Outcome Measures: Immediate fascial closure rate, infection rate, time to fascial closure, time to initiation of enteral feeding, time to achievement of full enteral feeds, time of hyperalimentation requirement, and length of hospital stay. Results: The rate of immediate fascial closure was lower in the post implementation group (58% before vs 20% after implementation, P<.001). Overall length of stay, time to enteral feeding, and infection rates were not significantly different between the 2 groups. Conclusions: The use of an SLS placed at the bedside has resulted in lower immediate fascial closure rates for infants with gastroschisis without significant detrimental clinical outcome. The main benefit of using the bedside placed SLS is the avoidance of urgent surgical intervention. For patients undergoing delayed fascial closure, use of the bedside SLS resulted in shorter times to definitive fascial closure. [ABSTRACT FROM AUTHOR]

Hypothesis: Multimedia delivery of cognitive content paired with faculty-supervised partial task simulation for both excision of a simulated skin lesion with subsequent wound closure and hand-sewn bowel anastomosis would be an effective method for developing appropriate procedural skills among junior residents. Design: Prospective cohort study. Setting: University-based surgical residency. Participants: First- and second-year surgical residents (n = 45). Interventions: Surgical residents were given comprehensive instructional materials, including structured curricula with goals and objectives, text, figures, and narrated expert digital video, before the training session. A 4-hour, standardized, laboratory-based instruction session was then performed in small groups, which emphasized faculty-supervised practice. Residents were asked to (1) excise a skin lesion and close the wound and (2) perform hand-sewn bowel anastomosis. These 2 tasks were assessed before and after supervised practice. Performances were video recorded. Residents were surveyed before and after training. Main Outcome Measures: Time to completion and Objective Structured Assessment of Technical Skill global rating scale score based on video recordings were evaluated by blinded reviewers. Final product quality was measured by anastomotic leak pressure and by wound closure aesthetic quality. Results: Residents perceived the laboratory training to be equal to training in the operating room for skin closure and superior to training in the operating room for bowel anastomosis. Residents perceived time spent on both tasks to be "perfect." Mean objective scores improved significantly on 5 of 6 outcome measures. Conclusions: Junior resident surgical performance improved substantially with 4 hours of laboratory-based, faculty-supervised practice. Both first- and second-year residents benefited from this training. These data show that curriculum-driven, faculty-supervised instruction in a laboratory setting is beneficial in the training of junior surgical residents. [ABSTRACT FROM AUTHOR]