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Early geoscientists recognized that salt marsh sediment overlying terrestrial deposits (e.g., soil containing the preserved, in-situ stumps of freshwater trees) represented submergence of the older, buried landscape at a time in the past (e.g., Bartram, 1791; Lyell, 1849). After the development of radiocarbon dating in the late 1940s (e.g., Libby 1961) it became possible to determine when salt marsh sediment was deposited and sea-level research began to focus first on building and then on interpreting Holocene relative sea level (RSL) curves (e.g., Bradley, 1953; Redfield and Rubin, 1962; Bloom and Stuiver, 1963; van de Plassche et al. 1989; Gehrels et al. 1996; Shennan and Horton, 2002). Conceptually relative sea level (RSL) is the elevation of the sea surface relative to the land surface at a specific location and averaged over a period of time to negate the influence of tides and seasonal to annual variability. For example, RSL measured by tide gauges is often expressed as a monthly or annual average, while RSL reconstructions from coastal sediment are inherently time averaged over several years to decades. A variety of physical processes acting on local-to-global spatial scales and on temporal scales from minutes to millennia can cause RSL to change across space and through time. Therefore, measured or reconstructed RSL is specific to a time and place and is often the net outcome of multiple processes acting simultaneously. Proxy-based RSL reconstructions generated by interrogation of salt marsh sediment preserved in the coastal stratigraphic record are valuable in advancing our understanding of Holocene climate (e.g., Kemp et al. 2011), the structure of Earth’s interior (e.g., the viscosity and structure of the mantle; e.g., Shennan and Horton, 2002; Engelhart et al. 2011a), and of physical driving mechanisms of past, present, and future sea-level change (e.g., Kopp et al. 2016).
The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
This is the first report on the association between trauma exposure and depression from the Advancing Understanding of RecOvery afteR traumA(AURORA) multisite longitudinal study of adverse post-traumatic neuropsychiatric sequelae (APNS) among participants seeking emergency department (ED) treatment in the aftermath of a traumatic life experience.
We focus on participants presenting at EDs after a motor vehicle collision (MVC), which characterizes most AURORA participants, and examine associations of participant socio-demographics and MVC characteristics with 8-week depression as mediated through peritraumatic symptoms and 2-week depression.
Eight-week depression prevalence was relatively high (27.8%) and associated with several MVC characteristics (being passenger v. driver; injuries to other people). Peritraumatic distress was associated with 2-week but not 8-week depression. Most of these associations held when controlling for peritraumatic symptoms and, to a lesser degree, depressive symptoms at 2-weeks post-trauma.
These observations, coupled with substantial variation in the relative strength of the mediating pathways across predictors, raises the possibility of diverse and potentially complex underlying biological and psychological processes that remain to be elucidated in more in-depth analyses of the rich and evolving AURORA database to find new targets for intervention and new tools for risk-based stratification following trauma exposure.
Virus outbreaks such as the current SARS-CoV-2 pandemic are challenging for health care workers (HCWs), affecting their workload and their mental health. Since both, workload and HCW's well-being are related to the quality of care, continuous monitoring of working hours and indicators of mental health in HCWs is of relevance during the current pandemic. The existing investigations, however, have been limited to a single study period. We examined changes in working hours and mental health in Swiss HCWs at the height of the pandemic (T1) and again after its flattening (T2).
We conducted two cross-sectional online studies among Swiss HCWs assessing working hours, depression, anxiety, and burnout. From each study, 812 demographics-matched participants were included into the analysis. Working hours and mental health were compared between the two samples.
Compared to prior to the pandemic, the share of participants working less hours was the same in both samples, whereas the share of those working more hours was lower in the T2 sample. The level of depression did not differ between the samples. In the T2 sample, participants reported more anxiety, however, this difference was below the minimal clinically important difference. Levels of burnout were slightly higher in the T2 sample.
Two weeks after the health care system started to transition back to normal operations, HCWs' working hours still differed from their regular hours in non-pandemic times. Overall anxiety and depression among HCWs did not change substantially over the course of the current SARS-CoV-2 pandemic.
Growing evidence showed that coronavirus disease 2019 (COVID-19) infection may present with neurological manifestations. This review aimed to determine the neurological manifestations and complications in COVID-19.
We conducted a systematic review and meta-analysis that included cohort and case series/reports involving a population of patients confirmed with COVID-19 infection and their neurologic manifestations. We searched the following electronic databases until April 18, 2020: PubMed, Embase, Scopus, and World Health Organization database (PROSPERO registration number: CRD42020180658).
From 403 articles identified, 49 studies involving a total of 6,335 confirmed COVID-19 cases were included. The random-effects modeling analysis for each neurological symptom showed the following proportional point estimates with 95% confidence intervals: “headache” (0.12; 0.10–0.14; I2 = 77%), “dizziness” (0.08; 0.05–0.12; I2 = 82%), “headache and dizziness” (0.09; 0.06–0.13; I2 = 0%), “nausea” (0.07; 0.04–0.11; I2 = 79%), “vomiting” (0.05; 0.03–0.08; I2 = 74%), “nausea and vomiting” (0.06; 0.03–0.11; I2 = 83%), “confusion” (0.05; 0.02–0.14; I2 = 86%), and “myalgia” (0.21; 0.18–0.25; I2 = 85%). The most common neurological complication associated with COVID-19 infection was vascular disorders (n = 23); other associated conditions were encephalopathy (n = 3), encephalitis (n = 1), oculomotor nerve palsy (n = 1), isolated sudden-onset anosmia (n = 1), Guillain–Barré syndrome (n = 1), and Miller–Fisher syndrome (n = 2). Most patients with neurological complications survived (n = 14); a considerable number of patients died (n = 7); and the rest had unclear outcomes (n = 12).
This review revealed that neurologic involvement may manifest in COVID-19 infection. What has initially been thought of as a primarily respiratory illness has evolved into a wide-ranging multi-organ disease.
This paper provides an up-to-date review of the problems related to the generation, detection and mitigation of strong electromagnetic pulses created in the interaction of high-power, high-energy laser pulses with different types of solid targets. It includes new experimental data obtained independently at several international laboratories. The mechanisms of electromagnetic field generation are analyzed and considered as a function of the intensity and the spectral range of emissions they produce. The major emphasis is put on the GHz frequency domain, which is the most damaging for electronics and may have important applications. The physics of electromagnetic emissions in other spectral domains, in particular THz and MHz, is also discussed. The theoretical models and numerical simulations are compared with the results of experimental measurements, with special attention to the methodology of measurements and complementary diagnostics. Understanding the underlying physical processes is the basis for developing techniques to mitigate the electromagnetic threat and to harness electromagnetic emissions, which may have promising applications.
Objectives: To adequately monitor the course of cognitive functioning in persons with moderate to severe dementia, relevant cognitive tests for the advanced dementia stages are needed. We examined the ability of a test developed for the advanced dementia stages, the Severe Impairment Battery Short version (SIB-S), to measure cognitive change over time. Second, we examined type of memory impairment measured with the SIB-S in different dementia stages. Methods: Participants were institutionalized persons with moderate to severe dementia (N = 217). The SIB-S was administered at 6-month intervals during a 2-year period. Dementia severity at baseline was classified according to Global Deterioration Scale criteria. We used mixed models to evaluate the course of SIB-S total and domain scores, and whether dementia stage at baseline affected these courses. Results: SIB-S total scores declined significantly over time, and the course of decline differed significantly between dementia stages at baseline. Persons with moderately severe dementia declined faster in mean SIB-S total scores than persons with moderate or severe dementia. Between persons with moderate and moderately severe dementia, there was only a difference in the rate of decline of semantic items, but not episodic and non-semantic items. Conclusions: Although modest floor and slight ceiling effects were noted in severe and milder cases, respectively, the SIB-S proved to be one of few available adequate measures of cognitive change in institutionalized persons with moderate to severe dementia. (JINS, 2019, 25, 204–214)
Malformed data-structures can lead to runtime errors such as arbitrary memory access or corruption. Despite this, reasoning over data-structure properties for low-level heap manipulating programs remains challenging. In this paper we present a constraint-based program analysis that checks data-structure integrity, w.r.t. given target data-structure properties, as the heap is manipulated by the program. Our approach is to automatically generate a solver for properties using the type definitions from the target program. The generated solver is implemented using a Constraint Handling Rules (CHR) extension of built-in heap, integer and equality solvers. A key property of our program analysis is that the target data-structure properties are shape neutral, i.e., the analysis does not check for properties relating to a given data-structure graph shape, such as doubly-linked-lists versus trees. Nevertheless, the analysis can detect errors in a wide range of data-structure manipulating programs, including those that use lists, trees, DAGs, graphs, etc. We present an implementation that uses the Satisfiability Modulo Constraint Handling Rules (SMCHR) system. Experimental results show that our approach works well for real-world C programs.
The episodic memory system allows us to experience the emotions of past, counterfactual, and prospective events. We outline how this phenomenological experience can convey motivational incentives for farsighted decisions. In this way, we challenge important arguments for Mahr & Csibra's (M&C's) conclusion that future-oriented mental time travel is unlikely to be a central function of episodic memory.
Radiocarbon (14C) activity in groundwater can be used to determine subsurface residence time up to ∼40 kyr, providing crucial information on dynamic properties of groundwater and on paleoclimate. However, commonly applied sampling methods for dissolved inorganic carbon (DIC-14C) are prone to low level of modern atmospheric contamination, resulting in underestimation of groundwater ages that cluster around 30–40 kyr. We extract CO2 gas from groundwater using a device originally developed for studies of noble gas radionuclides. Carbon is collected in the gas phase, eliminating the possibility of fostering microbial activities and aqueous chemical reactions during sample storage. This method collects CO2-14C and radiokrypton (81Kr and 85Kr) samples simultaneously. The presence of any shorter-lived 85Kr is used to evaluate the degree of atmospheric contamination during sampling or mixing of young groundwater. Most groundwater samples showed lower CO2-14C activities than those of DIC-14C, presumably due to the absence of atmospheric contamination. Samples with 81Kr age exceeding 150 kyr have no detectable CO2-14C except where mixing sources of young groundwater is suspected. These field data serve as confirmations for the reliability of the newly presented sample collection and CO2-14C method, and for the outstanding roles of radiokrypton isotopes in characterizing old groundwater.
Since its development, the Qualidem has had items that were considered unsuited for people with very severe dementia. This study attempted to investigate the applicability of all Qualidem items in people with all stages of dementia severity.
Four data sets that contained Qualidem observations on people with dementia were combined. Dementia severity was categorized based on the Global Deterioration Scale (GDS), with a dichotomization of very severe dementia (GDS 7) and others (GDS 1–6). Unidimensional latent-trait models (Mokken scaling) were estimated to fit the Qualidem responses in the overall sample and the dichotomized groups. Scalability was assessed using coefficients of homogeneity (Loevinger's H), while reliability was assessed with Cronbach's α and ρ.
Combining the four databases resulted in 4,354 Qualidem measurements. The scalability of all scales was considered acceptable in the overall sample, as well is in the subgroups (all H > 0.3). Additionally, the reliability was good–excellent in the scales: “positive affect,” “positive self-image,” “care relationship,” and “negative affect.” Reliability was questionable–acceptable for “feeling at home,” “social relations,” “social isolation,” and “restless tense behavior.” Reliability was poor for “having something to do.”
Statistical considerations allow using all Qualidem items in all dementia stages. Future research should determine balance of statistical- versus conceptual-based reasoning in this academic debate.
A recent theoretical literature highlights the role of endogenous firm entry as an internal amplification mechanism of business cycle fluctuations. The amplification mechanism works through the competition effect (CE) and the variety effect (VE). This paper tests the significance of this amplification mechanism, quantifies its importance, and disentangles the CE and VE. To this end, we estimate a medium-scale real business cycle model with firm entry for the U.S. economy. The CE and VE are estimated to be statistically significant. Together, they amplify the volatility of output by 8.5% relative to a model in which both effects are switched off. The CE accounts for most amplification, whereas the VE only plays a minor role.
Forest carbon sequestration plays an important role in reducing the build-up of greenhouse gases that are known to contribute to global climate change. However, private landowners will supply less carbon sequestration than would be socially desirable if they are unable to capture the economic value of sequestration. We examine the viability of offering landowners property tax subsidies for forest carbon sequestration (referred to as a ‘tax-based subsidy approach’). Waiving property taxes on forestland provides incentives for landowners to afforest non-forested land and/or sustain forests that are at risk of deforestation. We focus on 17 Tennessee counties and one Kentucky county, constituting one of 179 Bureau of Economic Analysis areas in the United States, as a case study. Higher forestland net return from waiving property taxes increases the share of forestland in the 18 counties, which in turn increases the accumulation of carbon in the forest ecosystem, suggesting that this is a viable approach. The annualized county-level cost of supplying forest carbon sequestration using a tax-based subsidy ranges between US$15.56 and US$563.58 per carbon tonne across the 18 counties. Relevant government agencies can use these estimates to target selected counties for more cost-effective adoption of the county-level tax-based subsidy approach.
Here, we investigate the effect of divalent metal (Zn2+, Cd2+ and Hg2+) on the structural and optoelectronic properties of methylammonium lead iodide perovskite materials prepared by the two-step deposition process. The incorporation of Cd2+ significantly improved the grain size, crystallinity, and charge carrier lifetime of CH3NH3PbI3. The inclusion of Hg2+ and Zn2+ improved the grain size compare to the control sample but adversely affected the optoelectronic properties of perovskite films. The Hg- and Zn-based impurities were formed on the surface of the films, which increased the charge trap density and lead to high non-radiative recombination rate. Time resolved photoluminescence measurements indicated that the Cd and Zn point defects do not create deep-level trap states, but the Zn-modified film showed a low lifetime due to morphology changes in the film and particle segregation on the surface.
Most patients born with CHD nowadays reach adulthood, and thus quality of life, life situation, and state of medical care aspects are gaining importance in the current era. The present study aimed to investigate whether patients’ assessment depends on their means of occupation. The findings are expected to be helpful in optimising care and for developing individual treatment plans.
The present study was based on an online survey conducted in cooperation with patient organisations. Participants were recruited from the database of the German National Register for Congenital Heart Defects. In total, 1828 individuals (777 males, 1051 females) took part. Participants were asked to rate aspects such their state of health on a six-tier scale (1=worst specification). Response behaviour was measured against the background of occupational details.
Training for or pursuing a profession was found to be significantly associated with participants’ rating of five of the six examined aspects (p<0.05). Sex seemed to play an important part in four of the six aspects.
An optimal treatment plan for adults with CHD should always consider aspects such as sex and employment status. To work out such an optimal and individual treatment plan for each adult CHD patient, an objective tool to measure patients’ actual CHD-specific knowledge precluding socially accepted response bias would be very useful.
This sequential nonrandomized intervention study investigated the role of preemptive isolation precautions plus ultrarapid polymerase chain reaction screening for methicillin-resistant Staphylococcus aureus (MRSA). Compared with no prophylactic isolation plus conventional microbiology MRSA screening, nosocomial MRSA colonization and total MRSA incidence per 10,000 patient days significantly decreased.
We present recent observation results of Sgr A* at millimeter obtained with VLBI arrays in Korea and Japan.
7 mm monitoring of Sgr A* is part of our AGN large project. The results at 7 epochs during 2013-2014, including high resolution maps, flux density and two-dimensional size measurements are presented. The source shows no significant variation in flux and structure related to the G2 encounter in 2014. According to recent MHD simulations by kawashima et al., flux and magnetic field energy can be expected to increase several years after the encounter; We will keep our monitoring in order to test this prediction.
Astrometric observations of Sgr A* were performed in 2015 at 7 and 3.5 millimeter simultaneously. Source-frequency phase referencing was applied and a combined ”core-shift” of Sgr A* and a nearby calibrator was measured. Future observations and analysis are necessary to determine the core-shift in each source.