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Incidence for depression increases during the perinatal period. Risk factors for depression may differentially affect each time period.
To assess demographic, psychological and obstetric risk factors that differentially affect prenatal and postpartum depression
A total of 169 subjects participated. Assessment was conducted during the first trimester, second trimester, third trimester, within a month after childbirth, and a month after childbirth. Demographic and obstetric measures, as well as psychological measures, including the Edinburgh Postnatal Depression Scale were conducted. Multiple regression and the Mann-Whitney U test were performed to examine the association between variables and depression scores.
Depression score was higher during the postpartum period than the prenatal period. Younger age was associated with depression during the first trimester. In the second trimester, less education, a history of depression and having stress within a year significantly affected depression scores. Smoking, artificial abortion and lack of support from family and parents correlated with depression during the third trimester. Within a month after childbirth, psychiatric and depression history, smoking, stress level within a year and lack of family support were associated with depression. At a month after childbirth, those who were primiparous and not breastfeeding had significantly higher depression scores.
This study identifies various risk factors for each gestational and postpartum period and suggests differential interventions for different perinatal periods.
It has been suggested that a cellularly unstable laminar flame, which is freely propagating in unbounded space, can accelerate and evolve into a turbulent flame with the neighbouring flow exhibiting the basic characteristics of turbulence. Famously known as self-turbulization, this conceptual transition in the flow regime, which arises from local interactions between the propagating wrinkled flamefront and the flow, is critical in extreme events such as the deflagration-to-detonation transition (DDT) leading to supernova explosions. Recognizing that such a transition in the flow regime has not been conclusively demonstrated through experiments, in this work, we present experimental measurements of flow characteristics of flame-generated ‘turbulence’ for expanding cellular laminar flames. The energy spectra of such ‘turbulence’ at different stages of cellular instability are analysed. A subsequent scaling analysis points out that the observed energy spectra are driven by the fractal topology of the cellularly unstable flamefront.
This SHEA white paper identifies knowledge gaps and challenges in healthcare epidemiology research related to coronavirus disease 2019 (COVID-19) with a focus on core principles of healthcare epidemiology. These gaps, revealed during the worst phases of the COVID-19 pandemic, are described in 10 sections: epidemiology, outbreak investigation, surveillance, isolation precaution practices, personal protective equipment (PPE), environmental contamination and disinfection, drug and supply shortages, antimicrobial stewardship, healthcare personnel (HCP) occupational safety, and return to work policies. Each section highlights three critical healthcare epidemiology research questions with detailed description provided in supplementary materials. This research agenda calls for translational studies from laboratory-based basic science research to well-designed, large-scale studies and health outcomes research. Research gaps and challenges related to nursing homes and social disparities are included. Collaborations across various disciplines, expertise and across diverse geographic locations will be critical.
The nonlinear evolution of electron Weibel instability in a symmetric, counterstream, unmagnetized electron–positron e−/e+ plasmas is studied by a 2D particle-in-cell (PIC) method. The magnetic field is produced and amplified by the Weibel instability, which extracts energy from the plasma anisotropy. A weakly relativistic drift velocity of 0.5c is considered for two counterstreaming e−/e+ plasma flows. Simulations show that in a homogeneous e−/e+ plasma distribution, the magnetic field amplifies exponentially in the linear regime and rapidly decays after saturation. However, in the case of inhomogeneous e−/e+ plasma distribution, the magnetic field re-amplifies at post-saturation. We also find that the amount of magnetic field amplification at post-saturation depends on the strength of the density inhomogeneity of the upstream plasma distribution. The temperature calculation shows that the finite thermal anisotropy exists in the case of an inhomogeneous plasma distribution which leads to the second-stage magnetic field amplification after the first saturation. Such density inhomogeneities are present in a variety of astrophysical sources: for example, in supernova remnants and gamma-ray bursts. Therefore, the present analysis is very useful in understanding these astrophysical sources, where anisotropic density fluctuations are very common in the downstream region of the relativistic shocks and the widely distributed magnetic field.
Understanding the clinical risk factors for COVID-19 disease severity and outcomes requires a combination of data from electronic health records and patient reports. To facilitate the collection of patient-reported data, as well as accelerate and standardize the collection of data about host factors, we have constructed a COVID-19 survey. This survey is freely available to the scientific community to send electronically for patients to complete online. This patient survey is designed to be comprehensive, yet not overly burdensome, to gather data useful for a range of clinical investigations, and to accommodate a wide variety of implementation settings including at a COVID-19 testing site, at home during infection or after recovery, and/or for individuals while they are hospitalized. A widely adopted standardized survey that can be implemented online with minimal resources can serve as a critical tool for combining and comparing data across studies to improve our understanding of COVID-19 disease.
Previous research has suggested an association between depression and subsequent acute stroke incidence, but few studies have examined any effect modification by sociodemographic factors. In addition, no studies have investigated this association among primary care recipients with hypertension.
We examined the anonymized records of all public general outpatient visits by patients aged 45+ during January 2007–December 2010 in Hong Kong to extract primary care patients with hypertension for analysis. We took the last consultation date as the baseline and followed them up for 4 years (until 2011–2014) to observe any subsequent acute hospitalization due to stroke. Mixed-effects Cox models (random intercept across 74 included clinics) were implemented to examine the association between depression (ICPC diagnosis or anti-depressant prescription) at baseline and the hazard of acute stroke (ICD-9: 430–437.9). Effect modification by age, sex, and recipient status of social security assistance was examined in extended models with respective interaction terms specified.
In total, 396 858 eligible patients were included, with 9099 (2.3%) having depression, and 10 851 (2.7%) eventually hospitalized for stroke. From the adjusted analysis, baseline depression was associated with a 17% increased hazard of acute stroke hospitalization [95% confidence interval (CI) 1.03–1.32]. This association was suggested to be even stronger among men than among women (hazard ratio = 1.29, 95% CI 1.00–1.67).
Depression is more strongly associated with acute stroke incidence among male than female primary care patients with hypertension. More integrated services are warranted to address their needs.
Electroconvulsive therapy (ECT) remains irreplaceable in the treatment of several psychiatric conditions. However, evidence derived using data from a national database to support its safety is limited. The aim of this study was to investigate in-hospital mortality among patients with psychiatric conditions treated with and without ECT.
Using data from the Taiwan National Health Insurance Research Database from 1997 to 2013, we identified 828,899 inpatients with psychiatric conditions, among whom 0.19% (n = 1571) were treated with ECT.
We found that ECT recipients were more frequently women, were younger and physically healthier, lived in more urbanized areas, were treated in medical centers, and had longer hospital stays. ECT recipients had lower odds of in-hospital mortality than did those who did not receive ECT. Moreover, no factor was identified as being able to predict mortality in patients who underwent ECT. Among all patients, ECT was not associated with in-hospital mortality after controlling for potential confounders.
ECT was indicated to be safe and did not increase the odds of in-hospital mortality. However, ECT appeared to be administered only on physically healthy but psychiatrically compromised patients, a pattern that is in opposition with the scientific evidence supporting its safety. Moreover, our data suggest that ECT is still used as a treatment of last resort in the era of modern psychiatry.
We herein report an experimental study to explore the effects of impact inertia, film thickness and viscosity on the dynamics of shape deformation of a drop impacting a liquid film. We have identified that the spreading dynamics shows a weak dependence on impact inertia, but strongly depends on the film thickness. For a thick film, the liquid surface deforms and absorbs part of the impact energy, and hence inhibits spreading of the drop. For a thin film, the drop motion is restricted by the bottom solid substrate, promoting spreading. The periodicity of the capillary controlled shape oscillation, on the other hand, is found to be independent of impact inertia and film thickness. The damping of the shape oscillation shows strong dependence on the film thickness, in that the oscillation decays faster for smaller film thicknesses, due to the enhanced viscous loss.
We herein report an experimental study on the morphological evolution of a vortex ring formed inside a liquid pool after it is impacted and penetrated by a coalescing drop of the same liquid. The dynamics of the penetrating vortex ring along with the deformation of the pool surface has been captured using simultaneous high-speed laser induced fluorescence and shadowgraph techniques. It is identified that the motion of such a vortex ring can be divided into three stages, during which inertial, capillary and viscous effects alternatingly play dominant roles to modulate the penetration process, resulting in linear, non-monotonic and decelerating motion in these three stages respectively. Furthermore, we also evaluate the relevant time and length scales of these three stages and subsequently propose a unified description of the downward motion of the penetrating vortex ring. Finally, we use the experimental data for a range of drop diameters and impact speeds to validate the proposed scaling.
Little is known about long-term employment outcomes for patients with first-episode schizophrenia-spectrum (FES) disorders who received early intervention services.
We compared the 10-year employment trajectory of patients with FES who received early intervention services with those who received standard care. Factors differentiating the employment trajectories were explored.
Patients with FES (N = 145) who received early intervention services in Hong Kong between 1 July 2001 and 30 June 2002 were matched with those who entered standard care 1 year previously. We used hierarchical clustering analysis to explore the 10-year employment clusters for both groups. We used the mixed model test to compare cluster memberships and piecewise regression analysis to compare the employment trajectories of the two groups.
There were significantly more patients who received the early intervention service in the good employment cluster (early intervention: N = 98 [67.6%]; standard care: N = 76 [52.4%]; P = 0.009). In the poor employment cluster, there was a significant difference in the longitudinal pattern between early intervention and standard care for years 1–5 (P < 0.0001). The number of relapses during the first 3 years, months of full-time employment during the first year and years of education were significant in differentiating the clusters of the early intervention group.
Results suggest there was an overall long-term benefit of early intervention services on employment. However, the benefit was not sustained for all patients. Personalisation of the duration of the early intervention service with a focus on relapse prevention and early vocational reintegration should be considered for service enhancement.