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Canonical models of costly signaling in international relations (IR) tend to assume costly signals speak for themselves: a signal's costliness is typically understood to be a function of the signal, not the perceptions of the recipient. Integrating the study of signaling in IR with research on motivated skepticism and asymmetric updating from political psychology, we show that individuals’ tendencies to embrace information consistent with their overarching belief systems (and dismiss information inconsistent with it) has important implications for how signals are interpreted. We test our theory in the context of the 2015 Joint Comprehensive Plan of Action (JCPOA) on Iran, combining two survey experiments fielded on members of the American mass public. We find patterns consistent with motivated skepticism: the individuals most likely to update their beliefs are those who need reassurance the least, such that costly signals cause polarization rather than convergence. Successful signaling therefore requires knowing something about the orientations of the signal's recipient.
Central-line–associated bloodstream infections (CLABSI) cause morbidity and mortality in critically ill children. We examined novel and/or modifiable risk factors for CLABSI to identify new potential targets for infection prevention strategies.
This single-center retrospective matched case-control study of pediatric intensive care unit (PICU) patients was conducted in a 60-bed PICU from April 1, 2013, to December 31, 2017. Case patients were in the PICU, had a central venous catheter (CVC), and developed a CLABSI. Control patients were in the PICU for ≥2 days, had a CVC for ≥3 days, and did not develop a CLABSI. Cases and controls were matched 1:4 on age, number of complex chronic conditions, and hospital length of stay.
Overall, 72 CLABSIs were matched to 281 controls. Univariate analysis revealed 14 risk factors, and 4 remained significant in multivariable analysis: total number of central line accesses in the 3 days preceding CLABSI (80+ accesses: OR, 4.8; P = .01), acute behavioral health needs (OR, 3.2; P = .02), CVC duration >7 days (8–14 days: OR, 4.2; P = .01; 15–29 days: OR, 9.8; P < .01; 30–59 days: OR, 17.3; P < .01; 60–89 days: OR, 39.8; P < .01; 90+ days: OR, 4.9; P = .01), and hematologic/immunologic disease (OR, 1.5; P = .05).
Novel risk factors for CLABSI in PICU patients include acute behavioral health needs and >80 CVC accesses in the 3 days before CLABSI. Interventions focused on these factors may reduce CLABSIs in this high-risk population.
Pott's puffy tumour is a rare complication of sinusitis. This osteomyelitis can affect the outer and inner tables of the frontal sinus. The treatment of Pott's puffy tumour combines medical and surgical approaches. Surgical approaches have traditionally been open, but endoscopic techniques have been adopted recently in select cases. The bony defect from debridement can be left alone, or closed with autografts or allografts.
To describe a technique for the reconstruction of a large skull vault after the debridement of extensive osteomyelitis of the anterior cranial vault.
Modified distraction osteogenesis is used in the cranial vault, to induce new bone formation. This is customarily used to lengthen long bones. The advantages of this technique include avoiding autologous grafts or alloplastic cranioplasty in the infected surgical bed, and allowing primary closure.
Early post-operative imaging results have been encouraging, with no reported complications.
Modified distraction osteogenesis is a novel technique in the primary reconstruction of calvarial bone.
Antibiotics are widely used by all specialties in the hospital setting. We evaluated previously defined high-risk antibiotic use in relation to Clostridioides difficile infections (CDIs).
We analyzed 2016–2017 data from 171 hospitals. High-risk antibiotics included second-, third-, and fourth-generation cephalosporins, fluoroquinolones, carbapenems, and lincosamides. A CDI case was a positive stool C. difficile toxin or molecular assay result from a patient without a positive result in the previous 8 weeks. Hospital-associated (HA) CDI cases included specimens collected >3 calendar days after admission or ≤3 calendar days from a patient with a prior same-hospital discharge within 28 days. We used the multivariable Poisson regression model to estimate the relative risk (RR) of high-risk antibiotic use on HA CDI, controlling for confounders.
The median days of therapy for high-risk antibiotic use was 241.2 (interquartile range [IQR], 192.6–295.2) per 1,000 days present; the overall HA CDI rate was 33 (IQR, 24–43) per 10,000 admissions. The overall correlation of high-risk antibiotic use and HA CDI was 0.22 (P = .003), and higher correlation was observed in teaching hospitals (0.38; P = .002). For every 100-day (per 1,000 days present) increase in high-risk antibiotic therapy, there was a 12% increase in HA CDI (RR, 1.12; 95% CI, 1.04–1.21; P = .002) after adjusting for confounders.
High-risk antibiotic use is an independent predictor of HA CDI. This assessment of poststewardship implementation in the United States highlights the importance of tracking trends of antimicrobial use over time as it relates to CDI.
Direct numerical simulations of high-speed mixing layers are used to characterize the effects of compressibility on the basis of local streamline topology and vortical structure. Temporal simulations of the mixing layers are performed using a finite volume gas-kinetic scheme for convective Mach numbers ranging from
. The focus of the study is on the transient development and the main objectives are to (i) investigate and characterize the turbulence suppression mechanism conditioned upon local streamline topology; and (ii) examine changes in the vortex vector field – distribution, magnitude and orientation – as a function of Mach number. We first reaffirm that kinetic energy suppression with increasing Mach number is due to a decrease in pressure–strain redistribution. Then, we examine the suppression mechanism conditioned upon topology and vortex structure. Conditional statistics indicate that (i) at a given Mach number, shear-dominated topologies generally exhibit more effective pressure–strain redistribution than vortical topologies; and (ii) for a given topology, the level of pressure–strain correlation mostly decreases with increasing Mach number. At each topology, with increasing Mach number, there is a corresponding decrease in turbulent shear stress and production leading to reduced kinetic energy. Further, as
increases, the proportion of vortex-dominated regions in the flow increases, leading to further reduction in the turbulent kinetic energy of the flow. Then, the orientation of vortical structures and direction of fluid rotation are examined using the vortex vector approach of Tian et al. (J. Fluid Mech., vol. 849, 2018, pp. 312–339). At higher
, the vortex vectors tend to be more aligned in the streamwise direction in contrast to low
wherein larger angles with streamwise direction are preferred. The connection between vortex orientation and kinetic energy production is also investigated. The findings lead to improved insight into turbulence suppression dynamics in high Mach number turbulent flows.
We study a DevOps software development process for a Product-Service System (PSS) using a design structure matrix (DSM) representation. We find unique features such as nested, planned iterations at differing rates which are not evident in conventional engineering development projects. We describe the impact of integrating ongoing operations into a development process and identify some of the enablers that lead to adoption of a DevOps process. We conclude by discussing the implications of our findings and raise questions for further research.
To increase knowledge of National Library of Medicine resources by using a train-the-trainer approach.
Workshops were held in spring 2016 to increase knowledge of 4 National Library of Medicine tools. Data were collected before the workshop and immediately, 3 months, and 1 year after the workshop. Knowledge questions were scored as 1 point per question; an aggregated knowledge score could range from 0 to 16 points. A paired t test assessed the change in knowledge from before to after the workshop.
Four workshops were hosted, with a total of 74 attendees. The response rate for the surveys ranged from 50% to 100%. Knowledge scores changed significantly from 7.2 to 11.9 (t = 15, P < .001). One year after the workshop, more of the participants reported having informally trained others (56.8%) than reported providing 1 or more formal training session (8.1%)(P < .001).
Objective measures of knowledge and information dissemination showed that the National Library of Medicine workshop was successful and resulted in both short- and long-term gains. This workshop could be repeated with other populations to further disseminate information regarding the National Library of Medicine tools, which could help improve disaster response.
We perform Lagrangian investigations of the dynamics of velocity gradients in compressible decaying turbulence. Specifically, we examine the evolution of the invariants of the velocity-gradient tensor. We employ well-resolved direct numerical simulations over a range of Mach number along with a Lagrangian particle tracker to examine trajectories of fluid particles in the space of the invariants of the velocity gradient tensor. This allows us to accurately measure the lifetimes of major topologies of compressible turbulence and provide an explanation of why some selective topologies tend to exist longer than the others. Further, the influence of dilatation on the lifetime of various topologies is examined. Finally, we explain why the so-called conditional mean trajectories (CMT) used previously by several researchers fail to predict the lifetime of topologies accurately.
To assess the feasibility of electronic data capture of postdischarge durations and evaluate total durations of antimicrobial exposure related to inpatient hospital stays.
Multicenter, retrospective cohort study.
Two community hospitals and 1 academic medical center.
Hospitalized patients who received ≥1 dose of a systemic antimicrobial agent.
We collected and reviewed electronic data on inpatient and discharge antimicrobial prescribing from April to September 2016 in 3 pilot hospitals. Inpatient antimicrobial use was obtained from electronic medication administration records. Postdischarge antimicrobial use was calculated from electronic discharge prescriptions. We completed a manual validation to evaluate the ability of electronic prescriptions to capture intended postdischarge antibiotics. Inpatient, postdischarge, and total lengths of therapy (LOT) per admission were calculated to assess durations of antimicrobial therapy attributed to hospitalization.
A total of 45,693 inpatient admissions were evaluated. Antimicrobials were given during 23,447 admissions (51%), and electronic discharge prescriptions were captured in 7,442 admissions (16%). Manual validation revealed incomplete data capture in scenarios in which prescribers avoided the electronic system. The postdischarge LOT among admissions with discharge antimicrobials was median 8 days (range, 1–360) with peaks at 5, 7, 10, and 14 days. Postdischarge days accounted for 38% of antimicrobial exposure days.
Discharge antimicrobial therapy accounted for a large portion of antimicrobial exposure related to inpatient hospital stays. Discharge prescription data can feasibly be captured through electronic prescribing records and may aid in designing stewardship interventions at transitions of care.
Vasodilation occurs as a result of the relaxation of the smooth muscle cells present in the walls of blood vessels. Various suitable models are available for the analysis of the vasoactive properties of drugs with therapeutic applications. But all these models have limitations, such as ethical issues and high cost. The purpose of this study is to develop an alternative model for studying the vasoactive properties of drugs using an in-ovo chicken embryo model. In the preliminary experiment, we used a well-known vasoconstrictor (adrenaline) and a vasodilator (spermine NoNoate) in the chick embryo area vasculosa and evaluated their concentration-response curve. Adrenaline (10 µM) and spermine NoNoate (10 µM) were administered in different arteries and veins and different positions of the right vitelline artery of the chick embryo. Results showed the middle of the vessel bed of the right vitelline artery having the best vasoactive effect compared to others. Finally, anti-hypertensive drugs, calcium channel blockers, and NOS agonists were administered in the chick embryo area vasculosa to validate the model. Results demonstrate that the chick embryo area vasculosa can be an alternative, robust, and unique in-ovo model for screening of anti-hypertensive drugs in real time.
The energy density of electrodeposition reactions makes them attractive for energy storage. Although its scientific inquiries nearly date back to the inception of electrochemistry, its behavior at microscopic dimensions (relevant to battery application) is mysteriously uncontrollable. We examine experimental reports of singular spatiotemporal evolutions with a hope to identify universality in deposition patterns. We conclude that a macroscopic mass transport instability cannot account for various growth morphologies and alludes to poorly understood materials interplay at smaller scales. We summarize representative characteristics of electrodeposition to encourage mechanistic investigations.
This paper presents a new method for creating and monitoring controlled localized negatively charged regions inside insulators with a scanning electron microscope (SEM). A localized buried charged region is created and observed close to the point where a high voltage primary beam (10 kV) strikes a metal–insulator–silicon specimen. The amount of buried charge within the insulator at any given moment can be dynamically monitored by detecting the appearance of a second peak in the secondary electron (SE) energy spectrum. SE energy spectral signals were obtained through the use of a compact high signal-to-noise energy analyzer attachment that was fitted on to the SEM specimen stage. An electrostatic model, together with Monte Carlo simulations, is presented to explain how the SE charge contrast effect functions. This model is then experimentally confirmed by using the SE energy spectral signal induced by a gallium ion beam inside a dual focused ion beam-SEM instrument.
This article provides a comprehensive examination of the time-series behavior of relationship banks around and during borrower distress. Relationship and outside loans have similar interest rates during distress and even 2 years prior to distress. Relative to outside loans in distress, relationship loans in distress have lower maturity. The fraction of bank lending given by relationship banks reduces during borrower distress. Overall, borrowers in distress do not derive benefits from relationship banks. These findings are inconsistent with models that suggest banks have an implicit commitment to help their borrowers in distress due to reputation concerns.
The present work aims to understand the effect of zinc and rare-earth element addition (i.e., 2 wt% Gd, 2 wt% Dy, and 2 wt% of Gd and Nd individually) on the microstructure evolution, mechanical properties, in vitro corrosion behavior, and cytotoxicity of Mg for biomedical application. The microstructure results indicate that the Mg–Zn–Gd alloy consists of the lamellar long period stacking ordered phase. The electrochemical and immersion corrosion behavior were studied in Hanks balanced salt solution. Enhanced corrosion resistance with reduced hydrogen evolution volume and magnesium (Mg2+) ion release were estimated for the Mg–Zn–Gd alloy as compared to the other two alloy systems. At the early stage of corrosion, formation of the oxide film inhibited the corrosion propagation. However, at the later stages, the breaking of the oxide film leads to shallow pitting mode of corrosion. The ultimate tensile strength of Mg–Zn–Gd–Nd is better than the other two alloys due to the uniform distribution of the Mg12Nd precipitate phase. The moderate strength in the Mg–Zn–Gd alloy is due to the low volume fraction of the secondary phase. The MTT (methylthiazoldiphenyl-tetrazolium bromide) assay study was carried out to understand the cell cytotoxicity on the alloy surfaces. Studies revealed that all three alloys had significant cellular adherence and no adverse effect on cells.
Vegetable and grain amaranths represent a vital source of micronutrients and protein in Asia and Africa. However, various foliar lepidopteran pests and stem-mining weevils hinder amaranth production. Insect-resistant cultivars can enhance the productivity of this crop. Here, we report on the performances of amaranth varieties screened for their resistance to insect pests under the field conditions at The World Vegetable Center stations in Asia and sub-Saharan Africa. We conducted two preliminary screening trials with a total of 263 entries from around the world in Taiwan and a third preliminary screening trial with 49 African-indigenous entries in Tanzania. Promising entries from these preliminary trials were collectively evaluated in an advanced screening trial in Tanzania, to identify lines resistant to foliar and stem-boring pests in East Africa. Four entries exhibited moderate resistance to foliar pests: TZ51 and TZ53 (Amaranthus cruentus), TZ34 (A. dubius) and TZ39 (Amaranthus sp.). Five entries showed moderate resistance to stem weevils: TZ06 and TZ27 (A. cruentus), TZ52 (A. graecizans), TZ59 (A. palmeri) and TZ07 (Amaranthus sp.). Lepidopteran pests affecting leaves were reared to adulthood and identified as Spoladea recurvalis (Crambidae), Spodoptera exigua (Noctuidae) and Spodoptera littoralis (Noctuidae). Stem weevil larvae were also reared and identified as: Neocleonus sannio Herbst, Gasteroclisus pr. rhomboidalis Boheman, Hypolixus pr. haerens Boheman and Baradine sp. (Curculionidae). These results highlight key amaranth pests in East Africa and identify insect-resistant entries that will be useful in breeding programmes and resistance studies.
In order to investigate the effect of dust production on the molecular absorption, we model the dust continuum and the 7.5 and 13.7 μm acetylene absorption features in the Spitzer IRS spectra of 148 carbon stars in the Large Magellanic Cloud (LMC). Our preliminary investigation does not find a strong correlation between the dust-production rate and the column density of acetylene for the LMC sample. However, we will construct more models at high optical depths and probe a larger range of dust properties for more robust results.
We derive azimuthally-averaged surface-brightness profiles of 16 AGB stars in the far-IR and sub-mm with the aim of studying the resolved historic mass loss in the extended circumstellar envelope. The PSF-subtracted extended component fluxes were found to be ∼40% of the total source flux. By fitting SEDs at each radial point we derive the dust temperature, column density and spectral index of emissivity via Bayesian inference. The measured dust-to-gas ratios were somewhat consistent with canonical values however with a large scatter.
Gas-to-dust ratios in Asymptotic Giant Branch (AGB) stars are used to calculate gas masses from measured dust masses and vice versa, but can vary widely and are rarely directly measured. In this work, we present spatially resolved gas and dust masses for a sample of 8 nearby AGB stars, using JCMT CO-line and continuum observations, and compare them. This serves as a pilot study for the Nearby Evolved Stars Survey (NESS; PI: P. Scicluna) project which will provide similar observations of ∼400 AGB stars in a volume-limited sample.
The asymptotic giant branch (AGB) stars with the reddest colors have the largest amounts of circumstellar dust. AGB stars vary in their brightness, and studies show that the reddest AGB stars tend to have longer periods than other AGB stars and are more likely to be fundamental mode pulsators than other AGB stars. Such stars are difficult to study, as they are often not detected at optical wavelengths. Therefore, they must be observed at infrared wavelengths. Using the Spitzer Space Telescope, we have observed a sample of very dusty AGB stars in the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) over Cycles 9 through 12 during the Warm Spitzer mission. For each cycle’s program, we typically observed a set of AGB stars at both 3.6 and 4.5 μm wavelength approximately monthly for most of a year. We present results from our analysis of the data from these programs.
We aim to analyse the co-added Herschel images of various categories of evolved stars in the LMC and SMC from the Herschel HERITAGE survey in order to identify, in a statistical sense, a cool historic dust mass component emitted by these sources. The fluxes derived from the co-added stacks can then be compared with those predicted by the GRAMS model grid in order to refine the DPRs estimated for the SMC and LMC.