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In 2018, an Ionplus 200 kV MIni-CArbon DAting System (MICADAS) accelerator mass spectrometer (AMS) was installed at the Laboratory of AMS Dating and the Environment, Nanjing University (NJU-AMS Laboratory), China. The NJU-AMS Laboratory is largely devoted to research on radiocarbon dating and 14C analysis in fields of earth, environmental and archaeological sciences. The laboratory has successfully employed various pretreatment methods, including routine pretreatment of tree rings, buried wood and subfossil wood, seeds, charcoal, pollen concentrates, organic matter, and shells. In this study, operational status of the NJU-AMS is presented, and results of radiocarbon measurements made on different sample types are reported. Measurements on international standards, references of known age, and blank samples demonstrate that the NJU-AMS runs stably and has good reproducibility on measurement of single samples. The facility is capable of measuring 14C in samples with the precision and accuracy that meet the requirements for investigating annual 14C changes, history-prehistory age dating, and Late Quaternary stratigraphic chronology research.
Natural zeolites may represent one of the greatest under-utilized resources of the mineral world. Even with their unique character and properties, issues of consistency, homogeneity and purity preclude them from many premium applications. We report a simple method to upgrade mineral sedimentary Na-chabazite from the well known Bowie, Arizona, deposit to near synthetic purity and consistency. During this alkaline-silicate digestion process, initially soft chabazite ore granules gain substantial mechanical strength. This may allow direct employment in adsorption and purification processes without the need for binding and forming. These granules manifest significantly improved adsorption properties, including enhanced water and CO2 adsorptivity.
Mineral chabazite has shown the unusual ability to surface template nanometal particles, especially Ag. A chabazite analog was synthesized from delaminated metakaolin. The chabazite formed retained the platy morphology of the base clay. This morphology is ideal for displaying surface-supported nanometal particles. The synthetic chabazite analog demonstrated the ability to form and support large concentrations of Ag nanoparticles, as observed in the related natural mineral. Due to greater Al content, the synthetic chabazite manifests significantly improved capacity for the formation of such Ag nanoparticles. As in the case of the mineral chabazite, surface Ag nanoparticles of high uniformity were observed in the range of 5–6 nm.
Patient-reported outcome measures provide valuable insights into health status after neurologic disease, but their relationships with function-based outcome measures remain incompletely understood. Here we evaluate the relationship between these two classes of measure using dimensionality-reduction techniques in patients after acute stroke and examine their associated patterns of neuroanatomical injury.
Participants and Methods:
Fifty-four adults with upper extremity motor deficits were serially assessed at four time points after stroke with functional outcome measures (Upper Extremity Fugl-Meyer, Barthel Index, modified Rankin Scale, Box and Blocks, 9- Hole Peg, Grip Strength) as well as patient-reported measures (PROMIS-Global Physical, Mental, and Social Health, Patient Health Questionnaire-9) of health status. At each timepoint after stroke, exploratory and confirmatory factor analysis were performed to identify and confirm the underlying factorial structure of the entire battery of outcome measures. Multivariate linear regression analysis was used to determine the amount of variance explained by clinical and demographic characteristics on extracted factors. Voxel-Based Lesion Symptom Mapping was used to examine the relationship between factors and patterns of neuroanatomical injury.
Results:
In the battery of stroke outcome measures, two factors were identified and retained, accounting for >78% of the overall variance across outcomes at every timepoint. Function-based measures loaded onto Factor 1 separately from patient-reported measures which loaded onto Factor 2. Results were consistent at each serial timepoint after stroke. Pre-stroke disability (p=0.03) and amount of damage to the corticospinal tract (p=0.001), explained significant variance in performance on Factor 1 (function-based outcomes), whereas education (p=0.01) and socioeconomic status (p=0.04) explained significant variance in performance on Factor 2 (PROMs). While function-based measures were related to injury to subcortical brain regions known to be important for motor function, patient-reported measures were related to injury to cortical brain regions including the insula and inferior parietal lobe, known to be important for affective processing and social cognition.
Conclusions:
Two distinct factors representing function-based and patient-reported measures of health status were extracted from the study battery of stroke outcome measures scored across the first year post-stroke. Each factor was associated with injury to brain regions concordant with the content of the represented assessments. These findings emphasize the distinct behavioral elements and neuroanatomical underpinnings of function-based and patient-reported outcome measures after stroke and have potential implications for precision rehabilitation.
Edited by
Dan Chamberlain, University of Turin,Aleksi Lehikoinen, Finnish Museum of Natural History, University of Helsinki,Kathy Martin, University of British Columbia, Vancouver
Alpine grassland and nival zones are characterized by variable environmental conditions, compressed breeding seasons, and limited resources such as food and nest site availability. As a result, high elevation habitats around the world contain an impressive diversity of unique bird species, highly specialized to thrive in challenging environmental conditions with limited breeding opportunities. In this chapter, we highlight the global diversity of alpine habitats and avifaunal communities. We first define general features of alpine and nival zones, before providing an overview of these habitats across 10 major regions around the world. Assembling a global list of alpine breeding birds, we then summarize what makes alpine avifauna unique and how communities vary regionally. Specifically, we focus on traits that characterize how species interact with their environment: i) alpine specialization and endemism, ii) nesting strategies, and iii) migration behaviour. Finally, we address some of the main eco-evolutionary drivers that shape these alpine communities, including climate, vegetation structure, food availability, and species interactions. We conclude by discussing the critical role snow dynamics play in maintaining many alpine bird communities and highlight the concerning trends associated with a rapidly changing climate that are putting pressure on alpine birds.
The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE), underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate masks and respirators exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus.
Design:
The 2 arms of the study included (1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment and (2) PPE treatment with MBL for 5 cycles of decontamination to determine maintenance of PPE performance.
Methods:
MBL treatment was used to inactivate coronaviruses on 3 N95 filtering facepiece respirator (FFR) and 2 medical mask models. We inoculated FFR and medical mask materials with 3 coronaviruses, including SARS-CoV-2, and we treated them with 10 µM MB and exposed them to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5 cycles of decontamination using multiple US and international test methods, and the process was compared with the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method.
Results:
Overall, MBL robustly and consistently inactivated all 3 coronaviruses with 99.8% to >99.9% virus inactivation across all FFRs and medical masks tested. FFR and medical mask integrity was maintained after 5 cycles of MBL treatment, whereas 1 FFR model failed after 5 cycles of VHP+O3.
Conclusions:
MBL treatment decontaminated respirators and masks by inactivating 3 tested coronaviruses without compromising integrity through 5 cycles of decontamination. MBL decontamination is effective, is low cost, and does not require specialized equipment, making it applicable in low- to high-resource settings.
We present a quasi-incompressible Navier–Stokes–Cahn–Hilliard (q-NSCH) diffuse interface model for two-phase fluid flows with variable physical properties that maintains thermodynamic consistency. Then, we couple the diffuse domain method with this two-phase fluid model – yielding a new q-NSCH-DD model – to simulate the two-phase flows with moving contact lines in complex geometries. The original complex domain is extended to a larger regular domain, usually a cuboid, and the complex domain boundary is replaced by an interfacial region with finite thickness. A phase-field function is introduced to approximate the characteristic function of the original domain of interest. The original fluid model, q-NSCH, is reformulated on the larger domain with additional source terms that approximate the boundary conditions on the solid surface. We show that the q-NSCH-DD system converges to the q-NSCH system asymptotically as the thickness of the diffuse domain interface introduced by the phase-field function shrinks to zero ($\epsilon \rightarrow 0$) with $\mathcal {O}(\epsilon )$. Our analytic results are confirmed numerically by measuring the errors in both $L^{2}$ and $L^{\infty }$ norms. In addition, we show that the q-NSCH-DD system not only allows the contact line to move on curved boundaries, but also makes the fluid–fluid interface intersect the solid object at an angle that is consistent with the prescribed contact angle.
Wellness is a term encompassing many aspects of the human experience, including physical health. Much of the regulation and maintenance of the human body occurs via hormonal expression. The human endocrine organs include the pituitary, adrenals, thyroid, testes, and ovaries, and produce many of the hormones responsible for maintaining homeostasis and optimal cellular function [1]. Many factors can alter hormonal expression, including aging, environmental toxins, disease, nutrition, and even stress [1]. Hormonal imbalances often lead to poorer health outcomes and decreased wellness in the long run. This chapter will give an overview of the most common endocrine disorders, how they impact wellness, and what has been done to improve patient quality of life (QOL).
When modelling subnational mortality rates, we should consider three features: (1) how to incorporate any possible correlation among subpopulations to potentially improve forecast accuracy through multi-population joint modelling; (2) how to reconcile subnational mortality forecasts so that they aggregate adequately across various levels of a group structure; (3) among the forecast reconciliation methods, how to combine their forecasts to achieve improved forecast accuracy. To address these issues, we introduce an extension of grouped univariate functional time-series method. We first consider a multivariate functional time-series method to jointly forecast multiple related series. We then evaluate the impact and benefit of using forecast combinations among the forecast reconciliation methods. Using the Japanese regional age-specific mortality rates, we investigate 1–15-step-ahead point and interval forecast accuracies of our proposed extension and make recommendations.
We consider a compositional data analysis approach to forecasting the age distribution of death counts. Using the age-specific period life-table death counts in Australia obtained from the Human Mortality Database, the compositional data analysis approach produces more accurate 1- to 20-step-ahead point and interval forecasts than Lee–Carter method, Hyndman–Ullah method and two naïve random walk methods. The improved forecast accuracy of period life-table death counts is of great interest to demographers for estimating survival probabilities and life expectancy, and to actuaries for determining temporary annuity prices for various ages and maturities. Although we focus on temporary annuity prices, we consider long-term contracts that make the annuity almost lifetime, in particular when the age at entry is sufficiently high.
A compact circularly polarized (CP) rectenna with low profile and high efficiency based on the artificial magnetic conductor (AMC) is proposed in this paper. The receiving CP antenna is a coplanar stripline fed dual rhombic loop with an AMC reflector. The proposed AMC reflector not only improves the antenna gain to 9.8 dBi but also decreases the profile to 0.1 λ0. The AMC reflector also makes the antenna have a harmonic suppression function so the low pass filter between the rectifying circuit and the antenna could be omitted and the rectenna has a compact structure. According to the measured results, the rectenna has the highest conversion efficiency of 76% on the load of 240 Ω with the received power of 117.5 mW. When the linearly polarized transmitting antenna is rotated, the conversion efficiency of the CP rectenna maintains a constant high conversion efficiency of 74%. The compact structure and CP operation of the rectenna made it a good candidate of the wireless battery for some electronic devices and far-distance microwave power transmission.
The Chinese Loess Plateau, the world’s largest and oldest loess record, preserves evidence of Asia’s long-term dust source dynamics, but there is uncertainty over the source of the deposits. Recent single-grain detrital zircon U-Pb age analysis has progressed this issue, but debates remain about source changes, and the generation and interpretation of zircon data. To address this, we analyze different groupings of new and existing datasets from the Loess Plateau and potential sources. We also present the results of a first high resolution sampling, multi-proxy provenance analysis of Beiguoyuan loess using U-Pb dating of detrital zircons and detrital garnet geochemistry. The data shows that some small source differences seem to exist between different areas on the Loess Plateau. However, sediment source appears to be unchanging between loess and palaeosols, supporting a recent material recycling hypothesis. Our zircon and garnet data demonstrates, however, that Beiguoyuan experienced a temporary, abrupt source shift during the last glacial maximum, implying that local dust sources became periodically active during the Quaternary. Our results highlight that grouping data to achieve bigger datasets could cause identification of misleading trends. Additionally, we suggest that multi-proxy single-grain approaches are required to gain further insight into Chinese Loess Plateau dust sources.
Little is known about the joint mental health effects of air pollution and tobacco smoking in low- and middle-income countries.
Aims
To investigate the effects of exposure to ambient fine particulate matter pollution (PM2.5) and smoking and their combined (interactive) effects on depression.
Method
Multilevel logistic regression analysis of baseline data of a prospective cohort study (n=41785). The 3-year average concentrations of PM2.5 were estimated using US National Aeronautics and Space Administration satellite data, and depression was diagnosed using a standardised questionnaire. Three-level logistic regression models were applied to examine the associations with depression.
Results
The odds ratio (OR) for depression was 1.09 (95% CI 1.01–1.17) per 10 μg/m3 increase in ambient PM2.5, and the association remained after adjusting for potential confounding factors (adjusted OR = 1.10, 95% CI 1.02–1.19). Tobacco smoking (smoking status, frequency, duration and amount) was also significantly associated with depression. There appeared to be a synergistic interaction between ambient PM2.5 and smoking on depression in the additive model, but the interaction was not statistically significant in the multiplicative model.
Conclusions
Our study suggests that exposure to ambient PM2.5 may increase the risk of depression, and smoking may enhance this effect.
The validity and reliability of the informant AD8 in primary healthcare has not been established. Therefore, the present study examined the validity and reliability of the informant AD8 in government subsidized primary healthcare centers in Singapore.
Methods:
Eligible patients (≥60 years old) were recruited from primary healthcare centers and their informants received the AD8. Patient-informant dyads who agreed for further cognitive assessments received the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Clinical Dementia Rating (CDR), and a locally validated formal neuropsychological battery at a research center in a tertiary hospital.
Results:
1,082 informants completed AD8 assessment at two primary healthcare centers. Of these, 309 patients-informant dyads were further assessed, of whom 243 (78.6%) were CDR = 0; 22 (7.1%) were CDR = 0.5; and 44 (14.2%) were CDR≥1. The mean administration time of the informant AD8 was 2.3 ± 1.0 minutes. The informant AD8 demonstrated good internal consistency (Cronbach's α = 0.85); inter-rater reliability (Intraclass Correlation Coefficient (ICC) = 0.85); and test–retest reliability (weighted κ = 0.80). Concurrent validity, as measured by the correlation between total AD8 scores and CDR global (R = 0.65, p < 0.001), CDR sum of boxes (R = 0.60, p < 0.001), MMSE (R = −0.39, p < 0.001), MoCA (R = −0.41, p < 0.001), as well as the formal neuropsychological battery (R = −0.46, p < 0.001), was good and consistent with previous studies. Construct validity, as measured by convergent validity (R ≥ 0.4) between individual items of AD8 with CDR and neuropsychological domains was acceptable.
Conclusions:
The informant AD8 demonstrated good concurrent and construct validity and is a reliable measure to detect cognitive dysfunction in primary healthcare.
Drowning is a major public health concern, yet little is known about the characteristics of drowning patients. The objectives of this study were to describe the demographic and clinical characteristics of out-of-hospital cardiac arrest (OHCA) attributed to drowning in Ontario and to compare the characteristics of OHCA attributed to drowning to those of presumed cardiac etiology.
Methods:
A retrospective, observational study was carried out of consecutive OHCA patients of drowning etiology in Ontario between August 2006 and July 2011. Bivariate analysis was used to evaluate differences between drowning and presumed cardiac etiologies.
Results:
A total of 31,763 OHCA patients were identified, and 132 (0.42%) were attributed to drowning. Emergency medical services treated 98 patients, whereas the remaining 34 met the criteria for legislative death. Overall, 5.1% of drowning patients survived to hospital discharge. When compared to patients of presumed cardiac etiology, drowning patients were younger and their arrest was more likely to be unwitnessed, present with a nonshockable initial rhythm, occur in a public location, and receive bystander cardiopulmonary resuscitation (CPR). A nonsignificant trend was noted for drowning cases to more frequently have a public access AED applied. There were no significant differences in the gender ratio or paramedic response times. Drowning patients were more likely to be transported to hospital but had a trend to be less likely to arrive with a return of spontaneous circulation. They were also morelikely to be admitted to hospital but had no difference in survival to hospital discharge.
Conclusions:
Significant differences exist between OHCA of drowning and presumed cardiac etiologies. Most drownings are unwitnessed, occur in public locations, and present with nonshockable initial rhythms, suggesting that treatment should focus on bystander CPR. Future initiatives should focus on strategies to improve supervision in targeted locations and greater emphasis on bystander-initiated CPR, both of which may reduce drowning mortality.