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Late-life depression (LLD) is common and frequently co-occurs with neurodegenerative diseases of aging. Little is known about how heterogeneity within LLD relates to factors typically associated with neurodegeneration. Varying levels of anxiety are one source of heterogeneity in LLD. We examined associations between anxiety symptom severity and factors associated with neurodegeneration, including regional brain volumes, amyloid beta (Aβ) deposition, white matter disease, cognitive dysfunction, and functional ability in LLD.
Participants and Measurements:
Older adults with major depression (N = 121, Ages 65–91) were evaluated for anxiety severity and the following: brain volume (orbitofrontal cortex [OFC], insula), cortical Aβ standardized uptake value ratio (SUVR), white matter hyperintensity (WMH) volume, global cognition, and functional ability. Separate linear regression analyses adjusting for age, sex, and concurrent depression severity were conducted to examine associations between anxiety and each of these factors. A global regression analysis was then conducted to examine the relative associations of these variables with anxiety severity.
Results:
Greater anxiety severity was associated with lower OFC volume (β = −68.25, t = −2.18, p = .031) and greater cognitive dysfunction (β = 0.23, t = 2.46, p = .016). Anxiety severity was not associated with insula volume, Aβ SUVR, WMH, or functional ability. When examining the relative associations of cognitive functioning and OFC volume with anxiety in a global model, cognitive dysfunction (β = 0.24, t = 2.62, p = .010), but not OFC volume, remained significantly associated with anxiety.
Conclusions:
Among multiple factors typically associated with neurodegeneration, cognitive dysfunction stands out as a key factor associated with anxiety severity in LLD which has implications for cognitive and psychiatric interventions.
We study the dynamic interaction of two gravity currents in a confined porous layer, one heavier and one lighter, partly inspired by the practice of geological $\mathrm {CO}_2$ sequestration in oil fields. Two coupled nonlinear advective-diffusive equations are derived to describe the time evolution of the profile shape of both the upper (lighter) and lower (heavier) currents. At early times, the upper and lower currents remain separated and propagate independently. As time progresses, the currents approach each other and start to interact. We have identified eight different regimes of gravity current interaction at late times, impacted by four dimensionless parameters, representing the flow rate partition, ratio of buoyancy over the injection force, and the viscosity contrasts between the two injecting and displaced fluids. By defining appropriate similarity variables at either the early or late times, the governing partial differential equations (PDEs) reduce to different ordinary differential equations (ODEs), corresponding to the classic nonlinear diffusion solutions at early times and eight different self-similar solutions at late times when the currents attach to each other. It is of interest to note that in four of the eight regimes of late-time interaction (regimes 2, 6–8), self-similar solutions can be constructed by combining appropriately the three basic solutions (i.e. shock, rarefaction and travelling wave solutions) identified during single fluid injection in confined porous layers. In the four other regimes (regimes 1, 3–5), implicit solutions in the form of logarithm or error functions are obtained due to the influence of flow confinement and interaction of gravity currents. Potential implications of the model and solutions are also briefly discussed in the context of ${\rm CO}_2$-water co-flooding for simultaneous ${\rm CO}_2$ sequestration and oil recovery.
Evaluation of adult antibiotic order sets (AOSs) on antibiotic stewardship metrics has been limited. The primary outcome was to evaluate the standardized antimicrobial administration ratio (SAAR). Secondary outcomes included antibiotic days of therapy (DOT) per 1,000 patient days (PD); selected antibiotic use; AOS utilization; Clostridioides difficile infection (CDI) cases; and clinicians’ perceptions of the AOS via a survey following the final study phase.
Design:
This 5-year, single-center, quasi-experimental study comprised 5 phases from 2017 to 2022 over 10-month periods between August 1 and May 31.
Setting:
The study was conducted in a 752-bed tertiary care, academic medical center.
Intervention:
Our institution implemented AOSs in the electronic medical record (EMR) for common infections among hospitalized adults.
Results:
For the primary outcome, a statistically significant decreases in SAAR were detected from phase 1 to phase 5 (1.0 vs 0.90; P < .001). A statistically significant decreases were detected in DOT per 1,000 PD (4,884 vs 3,939; P = .001), fluoroquinolone orders (407 vs 175; P < .001), carbapenem orders (147 vs 106; P = .024), and clindamycin orders (113 vs 73; P = .01). No statistically significant change in mean vancomycin orders was detected (991 vs 902; P = .221). A statistically significant decrease in CDI cases was also detected (7.8, vs 2.4; P = .002) but may have been attributable to changes in CDI case diagnosis. Clinicians indicated that the AOSs were easy to use overall and that they helped them select the appropriate antibiotics.
Conclusions:
Implementing AOS into the EMR was associated with a statistically significant reduction in SAAR, antibiotic DOT per 1,000 PD, selected antibiotic orders, and CDI cases.
Most research on biased public sector hiring highlights local politicians’ incentives to distribute government positions to partisan supporters. Other studies instead point to the role of bureaucratic managers in allocating government jobs to close contacts. We jointly consider the relative importance of each source of biased hiring as an allocation problem between managers and politicians who have different preferences regarding public sector hiring and different abilities to realize those preferences. We develop a theoretical model of each actor’s relative leverage and relative preferences for different types of public sector positions. We empirically examine our theory using the universe of payroll data in Kenyan local governments from 2004 to 2013. We find evidence of both patronage and bureaucratic favoritism, but with different types of bias concentrated in different types of government jobs, as our theory predicts. Our results highlight the inadequacy of examining political patronage alone without incorporating the preferences and leverage of the bureaucratic managers who are intricately involved in hiring processes.
Tuberculosis (TB) infection prevention and control (IPC) in healthcare facilities is key to reducing transmission risk. A framework for systematically improving TB IPC through training and mentorship was implemented in 9 healthcare facilities in China from 2017 to 2019.
Methods:
Facilities conducted standardized TB IPC assessments at baseline and quarterly thereafter for 18 months. Facility-based performance was assessed using quantifiable indicators for IPC core components and administrative, environmental, and respiratory protection controls, and as a composite of all control types We calculated the percentage changes in scores over time and differences by IPC control type and facility characteristics.
Results:
Scores for IPC core components increased by 72% during follow-up when averaged across facilities. The percentage changes for administrative, environmental, and respiratory protection controls were 39%, 46%, and 30%, respectively. Composite scores were 45% higher after the intervention. Overall, scores increased most during the first 6 months. There was no association between IPC implementation and provincial economic development or volume of TB services.
Conclusions:
TB IPC policies and practices showed most improvement early during implementation and did not differ consistently by facility characteristics. The training component of the project helped increase the capacity of healthcare professionals to manage TB transmission risks. Lessons learned here will inform national TB IPC guidance.
This article examines how public opinion—notably political activism and protest, as well as threats of violence, and violence itself—shaped the eventual resolution of the 1876 election. While not discounting the bargaining or machinations of party elites in forging an ultimate compromise, the standard explanation in the scholarly literature, the emphasis here adds important texture and nuance to the conversation, and strongly suggests that public opinion (broadly construed) played a significant, if not exclusive, role in pressuring party leaders to compromise on the eventual Electoral Commission Act that resolved the crisis. In particular, a series of January 1877 demonstrations held across several key states, coupled with the threat of “menace” at the heart of the Southern rifle clubs that were prominent in the campaign and its aftermath, provided strong incentives to partisan leaders and especially members of Congress to seek compromise to resolve the electoral crisis. The article also addresses the contested nature of mass meetings and protests in this era—and in general—and how partisans seek to define terms and behaviors to suit their political positions.
This study describes the local Emergency Medical Services (EMS) response and patient encounters corresponding to the civil unrest occurring over a four-day period in Spring 2020 in Indianapolis, Indiana (USA).
Methods:
This study describes the non-conventional EMS response to civil unrest. The study included patients encountered by EMS in the area of the civil unrest occurring in Indianapolis, Indiana from May 29 through June 1, 2020. The area of civil unrest defined by Indianapolis Metropolitan Police Department covered 15 blocks by 12 blocks (roughly 4.0 square miles) and included central Indianapolis. The study analyzed records and collected demographics, scene times, interventions, dispositions, EMS clinician narratives, transport destinations, and hospital course with outcomes from receiving hospitals for patients extracted from the area of civil unrest by EMS.
Results:
Twenty-nine patients were included with ages ranging from two to sixty-eight years. In total, EMS transported 72.4% (21 of 29) of the patients, with the remainder declining transport. Ballistic injuries from gun violence accounted for 10.3% (3 of 29) of injuries. Two additional fatalities from penetrating trauma occurred among patients without EMS contact within and during the civil unrest. Conditions not involving trauma occurred in 37.9% (11 of 29). Among transported patients, 33.3% (7 of 21) were admitted to the hospital and there was one fatality.
Conclusions:
While most EMS transports did not result in hospitalization, it is important to note that the majority of EMS calls did result in a transport. There was a substantial amount of non-traumatic patient encounters. Trauma in many of the encounters was relatively severe, and the findings imply the need for rapid extraction methods from dangerous areas to facilitate timely in-hospital stabilization.
This article explores the growth of abortion-related businesses in New York State that emerged to encourage Canadian women to travel across the border to access care. Referral agencies and clinics advertised their services, publicized their fees, and competed with each other. Canadian women living near the border were used to crossing to access goods and services not available in their home market. Their practice of traveling to New York for abortions was shaped by their experiences as consumers. The media used the language of commerce to explain this phenomenon, describing those involved in referral agencies as entrepreneurs and businessmen, highlighting the profits being made and evaluating the services being offered.
This study aimed to develop an efficient data collection and curation process for all drugs and natural health products (NHPs) used by participants to the Canadian Longitudinal Study on Aging (CLSA). The three-step sequential process consisted of (a) mapping drug inputs collected through the CLSA to the Health Canada Drug Product Database (DPD), (b) algorithm recoding of unmapped drug and NHP inputs, and (c) manual recoding of unmapped drug and NHP inputs. Among the 30,097 CLSA comprehensive cohort participants, 26,000 (86.4%) were using a drug or an NHP with a mean of 5.3 (SD 3.8) inputs per participant user for a total of 137,366 inputs. Of those inputs, 70,177 (51.1%) were mapped to the Health Canada DPD, 20,729 (15.1%) were recoded by algorithms, and 44,108 (32.1%) were manually recoded. The Direct algorithm correctly classified 99.4 per cent of drug inputs and 99.5 per cent of NHP inputs. We developed an efficient three-step process for drug and NHP data collection and curation for use in a longitudinal cohort.
Currently, workers in sand casting face harsh environments and the operation safety is poor. Existing pouring robots have insufficient stability and load-bearing capacity and cannot perform intelligent pouring according to the demand of pouring process. In this paper, a hybrid pouring robot is proposed to solve these limitations, and a vision-based hardware-in-the-loop (HIL) control technology is designed to achieve the real-time control problems of simulated pouring and pouring process. Firstly, based on the pouring mechanism and the motion demand of ladle, a hybrid pouring robot with a 2UPR-2RPU parallel mechanism as the main body is designed. And the equivalent hybrid kinematic model was established by using Eulerian method and differential motion. Subsequently, a motion control strategy based on HIL simulation technique was designed and presented. The working space of the robot was obtained through simulation experiments to meet the usage requirements. And the stability of the robot was tested through the key motion parameters of the robot joints. Based on the analysis of pouring quality and trajectory, optimal dynamic parameters for the experimental prototype are obtained through water simulation experiments, the pouring liquid height area is 35–40 cm, the average flow rate of pouring liquid is 112 cm3/s, and the ladle tilting speed is 0.0182 rad/s. Experimental results validate the reasonableness of the designed pouring robot structure. Its control system realizes the coordinated movement of each branch chain to complete the pouring tasks with different variable parameters. Consequently, the designed pouring robot will significantly enhance the automation level of the casting industry.
We present a suite of large-eddy simulations (LES) of a wind farm operating in conventionally neutral boundary layers. A fixed 1.6 GW wind farm is considered for 40 different atmospheric stratification conditions to investigate effects on wind-farm efficiency and blockage, as well as related gravity-wave excitation. A tuned Rayleigh damping layer and a wave-free fringe-region method are used to avoid spurious excitation of gravity waves, and a domain-size study is included to evaluate and minimize effects of artificial domain blockage. A fully neutral reference case is also considered, to distinguish between a case with hydrodynamic blockage only, and cases that include hydrostatic blockage induced by the air column above the boundary layer and the excitation of gravity waves therein. We discuss in detail the dependence of gravity-wave excitation, flow fields and wind-farm blockage on capping-inversion height, strength and free-atmosphere lapse rate. In all cases, an unfavourable pressure gradient is present in front of the farm, and a favourable pressure gradient in the farm, with hydrostatic contributions arising from gravity waves at least an order of magnitude larger than hydrodynamic effects. Using respectively non-local and wake efficiencies $\eta _{nl}$ and $\eta _{w}$, we observe a strong negative correlation between the unfavourable upstream pressure rise and $\eta _{nl}$, and a strong positive correlation between the favourable pressure drop in the farm and $\eta _{w}$. Using a simplified linear gravity-wave model, we formulate a simple scaling for the ratio $(1-\eta _{nl})/\eta _{w}$, which matches reasonably well with the LES results.
Imagine that we are on a train, playing with some mechanical systems. Why can’t we detect any differences in their behavior when the train is parked versus when it is moving uniformly? The standard answer is that boosts are symmetries of Newtonian systems. In this article, I use the case of a spring to argue that this answer is problematic because symmetries are neither sufficient nor necessary for preserving its behavior. I also develop a new answer according to which boosts preserve the relational properties on which the behavior of a system depends, even when they are not symmetries.
This study introduces an analytical solution for the laminar entrance flow in circular pipes, aiming to confirm the occurrence of velocity overshoot. Velocity overshoot is characterised by the maximum axial velocity appearing near the pipe wall instead of the central axis. Similar to the previous studies, the analytical solution is derived from the parabolised Navier–Stokes equation; however, the specific approach used in linearising the momentum equation has not been attempted before. The accuracy of this analytical solution has been verified through a comprehensive comparison with various published experimental data. The existence of velocity overshoot at a short distance from the inlet, which is evident in numerous numerical calculations based on the full Navier–Stokes equations and corroborated by recent magnetic resonance (MR) velocimetry experiments, is identified analytically for the first time. The parabolised Navier–Stokes equation has inherent self-similarity with respect to the Reynolds number, implying that $Re$ is incorporated into the dimensionless variables rather than serving as an independent flow parameter. According to both MR velocimetry measurements and the present analytical solution, the self-similarity is not valid immediately following the pipe inlet, and this becomes more evident as $Re$ decreases; hence, the analytical solution derived from the parabolised Navier–Stokes equation cannot accurately predict the evolution of the velocity profile within this region near the pipe inlet.
The antibacterial, antifungal and antioxidant effects of halloysite nanoclay, Cloisite 10A (C10A) and Cloisite 15A (C15A) organonanoclays were examined in this study. The antimicrobial action was assessed using the agar-well method and the disc diffusion method. The free radical-scavenging effects of the clays were determined using the 2,2-diphenyl-1-picrylhydrazyl method. Halloysite showed antimicrobial activity against Pseudomonas aeruginosa, Enterococcus faecalis and Staphylococcus aureus. C10A was effective against both Gram-positive bacteria (S. aureus, Listeria monocytogenes, Bacillus subtilis and E. faecalis) and Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae and P. aeruginosa). Additionally, only C10A was found to have an antimicrobial effect on Candida glabrata of 18 mm amongst the tested clays. C15A showed an antimicrobial effect on S. aureus and K. pneumoniae. It was determined that the antifungal properties of organoclays were higher than those of halloysite. The most effective clay type was determined to be C10A. The positively charged inner surface of the halloysite nanoclay can provide a large area to which negatively charged free radicals can attach. The modified C15A used in this study has two long-chain alkyl groups attached, whereas the modified C10A has a single long-chain alkyl group and a benzyl group attached. It is proposed that the differences in these antimicrobial effects are due to the structures of the molecules. According to these results, organoclays as green source materials could be used as additives and coatings in food processing, biomedical devices, filters and paints due to their antimicrobial and antioxidant properties.
Reinforcement learning (RL) has been successfully applied to a wealth of robot manipulation tasks and continuous control problems. However, it is still limited to industrial applications and suffers from three major challenges: sample inefficiency, real data collection, and the gap between simulator and reality. In this paper, we focus on the practical application of RL for robot assembly in the real world. We apply enlightenment learning to improve the proximal policy optimization, an on-policy model-free actor-critic reinforcement learning algorithm, to train an agent in Cartesian space using the proprioceptive information. We introduce enlightenment learning incorporated via pretraining, which is beneficial to reduce the cost of policy training and improve the effectiveness of the policy. A human-like assembly trajectory is generated through a two-step method with segmenting objects by locations and iterative closest point for pretraining. We also design a sim-to-real controller to correct the error while transferring to reality. We set up the environment in the MuJoCo simulator and demonstrated the proposed method on the recently established The National Institute of Standards and Technology (NIST) gear assembly benchmark. The paper introduces a unique framework that enables a robot to learn assembly tasks efficiently using limited real-world samples by leveraging simulations and visual demonstrations. The comparative experiment results indicate that our approach surpasses other baseline methods in terms of training speed, success rate, and efficiency.
This research note contributes updated and extended point estimates of the ideological positions of Brazilian political parties and novel estimates of the positions of all presidents since redemocratization in 1985. Presidents and parties are jointly responsible for the operability of Brazil’s version of coalitional presidentialism. Locating these key political actors in a unidimensional left–right space over time reveals rising challenges to the institutional matrix, particularly since 2013. Ideological polarization among parties has sharply increased, presidents have become more distant from Congress, and the political center has become increasingly vacated. Coalitional presidentialism is being subjected to unprecedented ideological stress as President Luiz Inácio Lula da Silva begins his third term in office.