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We report on experimental observation of non-laminar proton acceleration modulated by a strong magnetic field in laser irradiating micrometer aluminum targets. The results illustrate the coexistence of ring-like and filamentation structures. We implement the knife edge method into the radiochromic film detector to map the accelerated beams, measuring a source size of 30–110 μm for protons of more than 5 MeV. The diagnosis reveals that the ring-like profile originates from low-energy protons far off the axis whereas the filamentation is from the near-axis high-energy protons, exhibiting non-laminar features. Particle-in-cell simulations reproduced the experimental results, showing that the short-term magnetic turbulence via Weibel instability and the long-term quasi-static annular magnetic field by the streaming electric current account for the measured beam profile. Our work provides direct mapping of laser-driven proton sources in the space-energy domain and reveals the non-laminar beam evolution at featured time scales.
To assess extent of a healthcare-associated outbreak of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) and to evaluate the effectiveness of infection control measures, including universal masking.
Design:
Outbreak investigation including 4 large-scale point-prevalence surveys.
Setting:
Integrated VA healthcare system with 2 facilities and 330 beds.
Participants:
Index patient and 250 exposed patients and staff.
Methods:
We identified exposed patients and staff and classified them as probable and confirmed cases based on symptoms and testing. We performed a field investigation and an assessment of patient and staff interactions to develop probable transmission routes. Infection prevention interventions included droplet and contact precautions, employee quarantine, and universal masking with medical and cloth face masks. We conducted 4 point-prevalence surveys of patient and staff subsets using real-time reverse-transcriptase polymerase chain reaction for SARS-CoV-2.
Results:
Among 250 potentially exposed patients and staff, 14 confirmed cases of coronavirus disease 2019 (COVID-19) were identified. Patient roommates and staff with prolonged patient contact were most likely to be infected. The last potential date of transmission from staff to patient was day 22, the day universal masking was implemented. Subsequent point-prevalence surveys in 126 patients and 234 staff identified 0 patient cases and 5 staff cases of COVID-19, without evidence of healthcare-associated transmission.
Conclusions:
Universal masking with medical face masks was effective in preventing further spread of SARS-CoV-2 in our facility in conjunction with other traditional infection prevention measures.
Social cognition has not previously been assessed in treatment-naive patients with chronic schizophrenia, in patients over 60 years of age, or in patients with less than 5 years of schooling.
Methods
We revised a commonly used measure of social cognition, the Reading the Mind in the Eyes Test (RMET), by expanding the instructions, using both self-completion and interviewer-completion versions (for illiterate respondents), and classifying each test administration as ‘successfully completed’ or ‘incomplete’. The revised instrument (RMET-CV-R) was administered to 233 treatment-naive patients with chronic schizophrenia (UT), 154 treated controls with chronic schizophrenia (TC), and 259 healthy controls (HC) from rural communities in China.
Results
In bivariate and multivariate analyses, successful completion rates and RMET-CV-R scores (percent correct judgments about emotion exhibited in 70 presented slides) were highest in HC, intermediate in TC, and lowest in UT (adjusted completion rates, 97.0, 72.4, and 49.9%, respectively; adjusted RMET-CV-R scores, 45.4, 38.5, and 34.6%, respectively; all p < 0.02). Stratified analyses by the method of administration (self-completed v. interviewer-completed) and by education and age (‘educated-younger’ v. ‘undereducated-older’) show the same relationship between groups (i.e. NC>TC>UT), though not all differences remain statistically significant.
Conclusions
We find poorer social cognition in treatment-naive than in treated patients with chronic schizophrenia. The discriminant validity of RMET-CV-R in undereducated, older patients demonstrates the feasibility of administering revised versions of RMET to patients who may otherwise be considered ineligible due to education or age by changing the method of test administration and carefully assessing respondents' ability to complete the task successfully.
Incentivizing the development of interdisciplinary scientific teams to address significant societal challenges usually takes the form of pilot funding. However, while pilot funding is likely necessary, it is not sufficient for successful collaborations. Interdisciplinary collaborations are enhanced when team members acquire competencies that support team success.
Methods:
We evaluated the impact of a multifaceted team development intervention that included an eight-session workshop spanning two half-days. The workshop employed multiple methods for team development, including lectures on empirically supported best practices, skills-based modules, role plays, hands-on planning sessions, and social interaction within and across teams. We evaluated the impact of the intervention by (1) asking participants to assess each of the workshop sessions and (2) by completing a pre/postquestionnaire that included variables such as readiness to collaborate, goal clarity, process clarity, role ambiguity, and behavioral trust.
Results:
The content of the team development intervention was very well received, particularly the workshop session focused on psychological safety. Comparison of survey scores before and after the team development intervention indicated that scores on readiness to collaborate and behavioral trust were significantly higher among participants who attended the workshop. Goal clarity, process clarity, and role ambiguity did not differ among those who attended versus those who did not.
Conclusions:
Multicomponent team development interventions that focus on key competencies required for interdisciplinary teams can support attitudes and cognitions that the literature on the science of team science indicate are predictive of success. We offer recommendations for the design of future interventions.
This article reviews the advancements and prospects of liquid cell transmission electron microscopy (TEM) imaging and analysis methods in understanding the nucleation, growth, etching, and assembly dynamics of nanocrystals. The bonding of atoms into nanoscale crystallites produces materials with nonadditive properties unique to their size and geometry. The recent application of in situ liquid cell TEM to nanocrystal development has initiated a paradigm shift, (1) from trial-and-error synthesis to a mechanistic understanding of the “synthetic reactions” responsible for the emergence of crystallites from a disordered soup of reactive species (e.g., ions, atoms, molecules) and shape-defined growth or etching; and (2) from post-processing characterization of the nanocrystals’ superlattice assemblies to in situ imaging and mapping of the fundamental interactions and energy landscape governing their collective phase behaviors. Imaging nanocrystal formation and assembly processes on the single-particle level in solution immediately impacts many existing fields, including materials science, nanochemistry, colloidal science, biology, environmental science, electrochemistry, mineralization, soft condensed-matter physics, and device fabrication.
United Nations (UN) personnel address a diverse range of political, social, and cultural crises throughout the world. Compared with other occupations routinely exposed to traumatic stress, there remains a paucity of research on mental health disorders and access to mental healthcare in this population. To fill this gap, personnel from UN agencies were surveyed for mental health disorders and mental healthcare utilization.
Methods
UN personnel (N = 17 363) from 11 UN entities completed online measures of generalized anxiety disorder (GAD), major depressive disorder (MDD), posttraumatic stress disorder (PTSD), trauma exposure, mental healthcare usage, and socio-demographic information.
Results
Exposure to one or more traumatic events was reported by 36.2% of survey responders. Additionally, 17.9% screened positive for GAD, 22.8% for MDD, and 19.9% for PTSD. Employing multivariable logistic regressions, low job satisfaction, younger age (<35 years of age), greater length of employment, and trauma exposure on or off-duty was significantly associated with all the three disorders. Among individuals screening positive for a mental health disorder, 2.05% sought mental health treatment within and 10.01% outside the UN in the past year.
Conclusions
UN personnel appear to be at high risk for trauma exposure and screening positive for a mental health disorder, yet a small percentage screening positive for mental health disorders sought treatment. Despite the mental health gaps observed in this study, additional research is needed, as these data reflect a large sample of convenience and it cannot be determined if the findings are representative of the UN.
In the 2015 review paper ‘Petawatt Class Lasers Worldwide’ a comprehensive overview of the current status of high-power facilities of ${>}200~\text{TW}$ was presented. This was largely based on facility specifications, with some description of their uses, for instance in fundamental ultra-high-intensity interactions, secondary source generation, and inertial confinement fusion (ICF). With the 2018 Nobel Prize in Physics being awarded to Professors Donna Strickland and Gerard Mourou for the development of the technique of chirped pulse amplification (CPA), which made these lasers possible, we celebrate by providing a comprehensive update of the current status of ultra-high-power lasers and demonstrate how the technology has developed. We are now in the era of multi-petawatt facilities coming online, with 100 PW lasers being proposed and even under construction. In addition to this there is a pull towards development of industrial and multi-disciplinary applications, which demands much higher repetition rates, delivering high-average powers with higher efficiencies and the use of alternative wavelengths: mid-IR facilities. So apart from a comprehensive update of the current global status, we want to look at what technologies are to be deployed to get to these new regimes, and some of the critical issues facing their development.
The thermal expansion behavior of polymer carbon nanotube (CNT) nanocomposites was investigated, and a micromechanical model was proposed to explain the highly nonlinear dependence of the coefficient of thermal expansion of the nanocomposite with CNT content for the CNT/polyimide nanocomposite. The microscopic analysis of CNT/polyimide matrix showed homogeneous dispersion of bundles composed of CNTs. Therefore, the proposed model to predict the thermal expansion behavior of the nanocomposite considered a random, homogeneous distribution of CNT bundles with a hierarchical arrangement of helical CNTs within the polymeric matrix. The CNT bundle morphology influenced the thermal expansion response of the nanocomposite through (i) bundle volume fraction and (ii) degree of helicity, affecting thermo-mechanical properties of the bundle. The effective, homogenized, properties of CNT bundles were determined by the elasticity based solution of the layered cylinder model. Bundle effective properties were used in the micromechanical model implementing the homogenized strain rule of the mixture expression to predict the thermal expansion behavior of nanocomposite in a wide range of CNT volume contents. The proposed micromechanical analytical model was found to correlate closely with the experimental results for polyimide/CNT nanocomposite films as measured using a digital image correlation method.
A fundamental problem of biology is to construct gene regulatory networks that characterize the operational interaction among genes. The term “gene” is used generically because such networks could involve gene products. Numerous inference algorithms have been proposed. The validity, or accuracy, of such algorithms is of central concern. Given data generated by a ground-truth network, how well does a model network inferred from the data match the data-generating network? This chapter discusses a general paradigm for inference validation based on defining a distance between networks and judging validity according to the distance between the original network and the inferred network. Such a distance will typically be based on some network characteristics, such as connectivity, rule structure, or steady-state distribution. It can also be based on some objective for which the model network is being employed, such as deriving an intervention strategy to apply to the original network with the aim of correcting aberrant behavior. Rather than assuming that a single network is inferred, one can take the perspective that the inference procedure leads to an “uncertainty class” of networks, to which belongs the ground-truth network. In this case, we define a measure of uncertainty in terms of the cost that uncertainty imposes on the objective, for which the model network is to be employed, the example discussed in the current chapter involving intervention in the yeast cell cycle network.
Introduction
From a translational perspective, we are interested in gene regulatory networks (GRNs) as a vehicle to derive optimal intervention strategies for regulatory pathologies, cancer being the salient example (see [1–3] for reviews and [4] for extensive coverage). Two basic intervention approaches have been considered for gene regulatory networks in the context of probabilistic Boolean networks (PBNs), external control and structural intervention [4], a key to intervention being that the dynamic behavior of a PBN can be modeled by a Markov chain, thereby making intervention in PBNs amenable to the theory of Markov decision processes. Perhaps we should note that the ability of Markov chains to model GRNs has a long history in translational genomics [5]. External control is based on externally manipulating the value of a control gene to beneficially alter the steady-state distribution, either indirectly via a one-step cost function [6] or directly via an objective function based on the steady-state distribution [7, 8].
Although the current literature offers some preliminary information about seeking feedback from various sources, a variable-centered approach has been adopted in which seeking feedback from supervisors and from subordinates was treated separately. We endeavored to extend this work through model-based cluster analysis, a person-centered approach, to identify distinct feedback source profiles in our sample of 209 front-line manager–supervisor dyads. Additionally, we aimed to explore whether such profiles differed between two feedback motives, perceived instrumental value and perceived image cost, as well as managers’ emotion regulation strategies. Results revealed six feedback source profiles and such profiles are associated not only with their perceived image cost and instrumental value but also with their emotion regulation strategies.
Future time orientation is essential if an employee is to be motivated to conduct activities that generate long-term rather than immediate gain, and which may involve risk. Given that feedback seeking requires the employee to slow down and seek input, it is surprising that little is known about the relationship between future time orientation and feedback seeking. Drawing upon psychological ownership theory and construal-level theory, we hypothesized a positive influence of future time orientation on feedback seeking from various sources (i.e., supervisors and co-workers). We also hypothesized job-based psychological ownership as a newly identified motive of feedback seeking and employed it to explain how future time orientation exerts influences. Tested with data from a sample of 228 subordinate–supervisor dyads from China, the results revealed that (1) future time orientation was positively related to feedback seeking from supervisors and co-workers and (2) job-based psychology ownership mediated the relationship between future time orientation and feedback seeking.
Mentoring received by protégés has been shown to play an important role in relieving protégés’ job-related stress. However, literature on the relationship between mentoring and job-related stress has yielded mixed and inconclusive results. Our research seeks to reconcile the conflicting implications by examining protégés’ individual traditionality and trust in mentor as moderators on the relationship between mentoring and job-related stress. We tested the hypotheses with data from a sample of 210 protégés from a large company in China. Results of our two-way and three-way interaction effect tests revealed that: (1) traditionality moderated the negative relationship between mentoring and job-related stress in such a way that the relationship was stronger for protégés with higher rather than lower traditionality; (2) the influence that mentoring had on job-related stress was strongest for protégés with both high traditionality and a high level of trust in mentor.
The advantages and limitations of image guidance systems for endoscopic sinus surgery are unclear. We report our experience and present a meta-analysis of the evidence.
Methods:
We performed a retrospective analysis of endoscopic sinus surgery procedures performed with versus without image guidance. A total of 355 cases was included. Primary outcomes included complication rates and time to revision surgery. A literature search was conducted to enable identification and analysis of studies of similar comparisons.
Results:
Within 1.5 years of the index sinus surgical procedure, the risk of revision surgery was significantly higher for patients treated with non-assisted versus computer-assisted endoscopic sinus surgery (p = 0.001). Meta-analysis did not indicate a reduction in complications or revision surgery procedures with the use of image guidance systems, although the majority of included studies showed a non-significant reduction in revision surgery.
Conclusion:
Our study offers some evidence that computer-assisted endoscopic sinus surgery may delay residual disease and reduce the requirement for revision surgery. Although this finding was not borne out in the meta-analysis, the majority of identified studies demonstrated a trend towards fewer revision procedures after computer-assisted endoscopic sinus surgery. This type of surgery may offer other advantages that are not easily measurable.
We have successfully developed a Seebeck coefficient Standard Reference Material (SRM™), Bi2Te3, that is essential for interlaboratory data comparison and for instrument calibration. Certification measurements were performed using a differential steady-state technique on 10 samples (15 measurements) randomly selected from a batch of 390 bars. The certified Seebeck coefficient values are provided from 10 to 390 K, and they are further supported by transient measurements. The availability of this SRM will validate measurement results, leading to a better understanding of the structure/property relationships and underlying physics of potential high-efficiency thermoelectric materials.
In order to investigate the dynamics of Septin4 (Sept4) expression and its function in the formation of fibrotic livers in mice infected with Schistosoma japonicum, we constructed the mouse model of S. japonicum egg-induced liver fibrosis for 24 weeks. Immunohistochemical staining, qRT-PCR and Western blot were used to detect the expression of Sept4 and α-smooth muscle actin (α-SMA). We found Sept4 localized in the perisinusoidal space where hepatic stellate cells (HSCs) distribute in the periphery of circumoval granulomas and the portal venule. The expression of Sept4 and α-SMA had a similar significant tendency of an up-regulation to a peak at 12 weeks post-infection (p.i.) followed by a down-regulation. At 24 weeks p.i. both were at a low level. These results suggest that Sept4 and α-SMA may interact together in HSCs. Based on this evidence, we hypothesize that Sept4 seems to be involved in the formation of inflammatory granulomata and subsequent liver fibrosis by regulating HSCs activation.
Both fish oil (FO) and curcumin have potential as anti-tumour and anti-inflammatory agents. To further explore their combined effects on dextran sodium sulphate (DSS)-induced colitis, C57BL/6 mice were randomised to four diets (2 × 2 design) differing in fatty acid content with or without curcumin supplementation (FO, FO+2 % curcumin, maize oil (control, MO) or MO+2 % curcumin). Mice were exposed to one or two cycles of DSS in the drinking-water to induce either acute or chronic intestinal inflammation, respectively. FO-fed mice exposed to the single-cycle DSS treatment exhibited the highest mortality (40 %, seventeen of forty-three) compared with MO with the lowest mortality (3 %, one of twenty-nine) (P = 0·0008). Addition of curcumin to MO increased (P = 0·003) mortality to 37 % compared with the control. Consistent with animal survival data, following the one- or two-cycle DSS treatment, both dietary FO and curcumin promoted mucosal injury/ulceration compared with MO. In contrast, compared with other diets, combined FO and curcumin feeding enhanced the resolution of chronic inflammation and suppressed (P < 0·05) a key inflammatory mediator, NF-κB, in the colon mucosa. Mucosal microarray analysis revealed that dietary FO, curcumin and FO plus curcumin combination differentially modulated the expression of genes induced by DSS treatment. These results suggest that dietary lipids and curcumin interact to regulate mucosal homeostasis and the resolution of chronic inflammation in the colon.