Cumulative Hours Research Articles

Utility of Noncognitive Admission Variables in the Prediction of Academic Success

Background: Graduate healthcare education programs commonly rely on cognitive measures such as grade point average for admission to their programs. Noncognitive measures are also collected at the time of application, with less information known about their utility in prediction of academic outcomes. This analysis observed the following noncognitive admission domains and their relationship with PA student academic success: employment hours, shadowing experience hours, research hours, hours spent in extracurricular activities, healthcare related activity hours, leadership experience, patient care experience hours, teaching hours, and volunteerism hours.
 Objective: This archival analysis aims to determine if noncognitive admission variables are predictive of Physician Assistant National Certifying Examination (PANCE) failure or academic attrition at a West Texas Physician Assistant (PA) Program.
 Methods: Institutional Review Board exemption was obtained; then a series of univariate logistic regression models were constructed to predict using applicant self-reported cumulative experience hours. Five cohorts (n=235) were evaluated by noncognitive variables using R statistical software (version 4.1.2).
 Results: Patient care experience hours showed a positive association with PANCE failure, while healthcare and teaching experience had positive trends with attrition. High GPA was protective against attrition when controlled for employment, research, and shadowing experiences, and also when controlled for leadership and patient care experience. High GPA was not a protective factor for PANCE failures.
 Conclusion: Contrary to our hypotheses, increased self-reported experiences did not show a protective effect against PANCE failure or attrition but were instead detrimental.

Evaluation of Clinical and Machine Data of Critically Ill Adult COVID Patients with Acute Kidney Injury Exposed to Enhanced Hemoadsorption during CRRT

Introduction: The FDA authorized the emergency use of enhanced hemoadsorption with oXiris in critically ill adult COVID patients with respiratory failure or severe disease to reduce inflammation. In this study, we evaluated critically ill adult COVID patients with acute kidney injury (AKI) who were exposed versus not exposed to enhanced hemoadsorption with oXiris during continuous renal replacement therapy (CRRT). Methods: Retrospective cohort study of critically ill adult COVID patients with AKI requiring CRRT. Exposure to oXiris was defined as receiving oXiris for >12 cumulative hours and more than one-third of the time within the first 72 h of CRRT. Study outcomes included filter-specific performance metrics and clinical outcomes such as ventilator requirement, mortality, and dialysis dependence. Inverse probability treatment weighting was used to balance potential confounders in weighted regression models. Results: 14,043 h of CRRT corresponding to 85 critically ill adult patients were analyzed. Among these, 2,736 h corresponded to oXiris exposure (n = 25 patients) and 11,307 h to a standard CRRT filter (n = 60 patients). Transmembrane pressures (TMPs) increased rapidly and were overall higher with oXiris versus standard filter, but filter life (median of 36.3 vs. 33.1 h, p = 0.913, respectively) and filter/clotting alarms remained similar in both groups. In adjusted models, oXiris exposure was not independently associated with the composite of hospital mortality and dialysis dependence at discharge (OR 2.13, 95% CI: 0.98–4.82, p = 0.06), but it was associated with fewer ventilator (β = −15.02, 95% CI: −29.23 to −0.82, p = 0.04) and intensive care unit days (β = −14.74, 95% CI: −28.54 to −0.95, p = 0.04) in survivors. Discussion/Conclusion: In critically ill adult COVID patients with AKI requiring CRRT, oXiris filters exhibited higher levels of TMP when compared to a standard CRRT filter, but no differences in filter life and filter/clotting alarm profiles were observed. The use of oXiris was not associated with improvement in clinical outcomes such as hospital mortality or dialysis dependence at discharge.

Theoretical study of the effect of fuel injection start pressure on the characteristics of the combustion process, indicators, and braking efficiency of the 2CH10.5/13 type engine

Introduction: Over time, demands on internal combustion engines are increasing, with a focus on fuel efficiency, emissions reduction, improved reliability, and cost-effective production and operation. Studying diesel engines like the 2CH10.5/13 is relevant due to their significant potential in the modern world. The purpose of study is to investigate the theoretical effect of the initial fuel injection pressure on the combustion process, engine braking performance and efficiency. Materials and Methods: The paper describes the methods of choosing injectors for diesel engines with a high-pressure fuel system. Results and Discussion: Using mathematical calculations and modeling is an effective means to prevent engine operation issues. Developing a dedicated calculation method is necessary to understand the impact of diesel fuel ignition volume on engine performance parameters. The results of experimental studies, which included non-motorised, motorised, and operational tests of diesel nozzles, are also presented. Studies have shown that after 4,000 cumulative hours of operation, the residual life of the injector nozzles is insignificant, since the dynamic performance of the diesel engine decreases to the limit value (7%). Conclusions: This may indicate the need for regular maintenance and replacement of nozzles in accordance with the manufacturer’s recommendations.

Changes and relationship of climate and late-rice yield in chenzhou city of south hunan province of CHINA

The changes and relationship of climate parameters and late-rice yield per unit area during the growth periods of late-rice from 2010 to 2019 were quantitatively analyzed in order to provide scientific guidance for countermeasures against climate change and sustainable production of late-rice. The climate parameters include cumulative daily sunshine hours (S), mean daily temperature (T), cumulative daily precipitation (P), mean daily relative humidity (H), daily highest and lowest temperatures (Th and Tl), days of high temperatures (DT ≥ 30℃ and DTh ≥ 35℃) and low temperature (DTl < 15℃). Results showed that: (i) Late-rice yield was significantly increased quadratically from 5621.33 kg hm2 in 2010 to 6333.65 kg hm2 in 2019 with a mean of 5959.2 kg hm2. (ii ) According to the suitable climate conditions for growth of late-rice, T and P were low but H was suitable in the whole field growth period of late-rice, T was suitable in the transplanting-tillering stage, but was low in the booting-heading and milk ripening-mature stage. DT ≥ 30℃, DTh ≥ 35℃ and DTl < 15℃ was meanly 7.7, 7.5 and 6.4 d, respectively, which showed possible occurrence of the damages to late-rice due to high and low temperatures. iii) Only T, Th and Tl in the booting-heading stage showed significant positive correlation with year, and the optimal regression models were in quadratic and exponential types. The climate parameters of S, T and Th in the boot-heading stage were significantly positively correlated with late-rice yield, and the optimal regression models were all in quadratic types. Daily highest temperature (Th) affected late-rice yield most (61.04%), followed by T (36.50%), and S affected least (2.46%). Considering the current conflict in the field planting periods between tobacco and late-rice, late rice varieties needs to be bred with short growth period and high tolerance to both high and low temperatures. Bangladesh J. Bot. 52(2): 639-647, 2023 (June) Special

Changes and relationship of climate and late-rice yield in chenzhou city of south hunan province of CHINA

The changes and relationship of climate parameters and late-rice yield per unit area during the growth periods of late-rice from 2010 to 2019 were quantitatively analyzed in order to provide scientific guidance for countermeasures against climate change and sustainable production of late-rice. The climate parameters include cumulative daily sunshine hours (S), mean daily temperature (T), cumulative daily precipitation (P), mean daily relative humidity (H), daily highest and lowest temperatures (Th and Tl), days of high temperatures (DT ≥ 30℃ and DTh ≥ 35℃) and low temperature (DTl < 15℃). Results showed that: (i) Late-rice yield was significantly increased quadratically from 5621.33 kg hm2 in 2010 to 6333.65 kg hm2 in 2019 with a mean of 5959.2 kg hm2. (ii ) According to the suitable climate conditions for growth of late-rice, T and P were low but H was suitable in the whole field growth period of late-rice, T was suitable in the transplanting-tillering stage, but was low in the booting-heading and milk ripening-mature stage. DT ≥ 30℃, DTh ≥ 35℃ and DTl < 15℃ was meanly 7.7, 7.5 and 6.4 d, respectively, which showed possible occurrence of the damages to late-rice due to high and low temperatures. iii) Only T, Th and Tl in the booting-heading stage showed significant positive correlation with year, and the optimal regression models were in quadratic and exponential types. The climate parameters of S, T and Th in the boot-heading stage were significantly positively correlated with late-rice yield, and the optimal regression models were all in quadratic types. Daily highest temperature (Th) affected late-rice yield most (61.04%), followed by T (36.50%), and S affected least (2.46%). Considering the current conflict in the field planting periods between tobacco and late-rice, late rice varieties needs to be bred with short growth period and high tolerance to both high and low temperatures. Bangladesh J. Bot. 52(2): 639-647, 2023 (June) Special

Association of duration and intensity of exercise with phenotypic expression in hypertrophic cardiomyopathy

ObjectivesThere is limited data regarding the impact of exercise on phenotypic expression in hypertrophic cardiomyopathy (HCM). We aimed to investigate whether such an association exists in a cohort of genotype-positive HCM patients. MethodsIn this cross-sectional study of genotype-positive HCM families, we used structured questionnaires to obtain data regarding intensity and duration of exercise of participants starting at the age of 10, as well as data regarding exercise recommendations and their impact on quality of life (QOL). The association of cumulative metabolic-equivalent hours of exercise at different ages with different measures of phenotypic expression (maximal wall thickness, left atrial diameter, extent of late gadolinium enhancement) was analyzed. ResultsThe study included 109 patients from 55 families, including 43 male (39%) and 90 (83%) phenotype-positive. No association was identified between exercise duration or intensity with any of the phenotypic markers with the exception of greater cumulative exercise associated with younger age at presentation. Similar results were obtained when analysis was limited to exercise until the age of 20, until the age of 30 or only after 30.Among phenotype-positive patients, 89% recalled receiving recommendations regarding exercise restriction, 29% noted reduction in exercise level following such recommendations and 25% noted this having a significant impact on their QOL. ConclusionWe found no association between exercise intensity or duration and phenotypic expression in genotype-positive HCM patients. These findings are important for physician-patient discussions and support the recent trend towards more permissive exercise restrictions in HCM.

A Multi-Objective Tri-Level Algorithm for Hub-and-Spoke Network in Short Sea Shipping Transportation

Hub-and-Spoke (H&S) network modeling is a form of transport topology optimization in which network joins are connected through intermediate hub nodes. The Short Sea Shipping (SSS) problem aims to efficiently disperse passenger flows involving multiple vessel routes and intermediary hubs through which passengers are transferred to their final destination. The problem contains elements of the Hub-and-Spoke and Travelling Salesman, with different levels of passenger flows among islands, making it more demanding than the typical H&S one, as the hub selection within nodes and the shortest routes among islands are internal optimization goals. This work introduces a multi-objective tri-level optimization algorithm for the General Network of Short Sea Shipping (GNSSS) problem to reduce travel distances and transportation costs while improving travel quality and user satisfaction, mainly by minimizing passenger hours spent on board. The analysis is performed at three levels of decisions: (a) the hub node assignment, (b) the island-to-line assignment, and (c) the island service sequence within each line. Due to the magnitude and complexity of the problem, a genetic algorithm is employed for the implementation. The algorithm performance has been tested and evaluated through several real and simulated case studies of different sizes and operational scenarios. The results indicate that the algorithm provides rational solutions in accordance with the desired sub-objectives. The multi-objective consideration leads to solutions that are quite scattered in the solution space, indicating the necessity of employing formal optimization methods. Typical Pareto diagrams present non-dominated solutions varying at a range of 30 percent in terms of the total distance traveled and more than 50 percent in relation to the cumulative passenger hours. Evaluation results further indicate satisfactory algorithm performance in terms of result stability (repeatability) and computational time requirements. In conclusion, the work provides a tool for assisting network operation and transport planning decisions by shipping companies in the directions of cost reduction and traveler service upgrade. In addition, the model can be adapted to other applications in transportation and in the supply chain.

Few-shot structural repair decision of civil aircraft based on deep meta-learning

To solve the difficulties in extracting general features of few-shot high-dimensional structural health monitoring data and making accurate repair decision, a civil aircraft structural repair decision method based on deep meta-learning (DML) is proposed in this paper. Firstly, multi-source structural health monitoring data such as component name, cumulative flight hours, inspection level and state parameters are collected as model input. In addition, the damage condition, repair level and repair definition are used as data labels. Secondly, DML model is used for few-shot learning of repair cases. Monitoring data and corresponding labels make up different target datasets, which can be used for training of base-learner and meta-learner. Thirdly, the historical cases in manual are used for in-sample prediction by meta-learning model, while the new cases are utilized for out-of-sample prediction by fine-tuning the initialized deep meta-learning model. Finally, the aircraft aluminum lap joint damage dataset is used for case study. The results show that the proposed deep meta-learning model can achieve higher accuracy when dealing with few-shot high-dimensional input. Compared with other models, the task oriented DML model has more strong generalization ability and higher classification accuracy in analyzing multi-task cases.

Strengthening COVID-19 pandemic response coordination through public health emergency operations centres (PHEOC) in Africa: Review of a multi-faceted knowledge management and sharing approach, 2020-2021.

The coronavirus disease 2019 (COVID-19) pandemic disrupted health security program implementation and incremental gains achieved after the West African Ebola outbreak in 2016 across Africa. Following cancellation of in-person events, a multi-faceted intervention program was established in May 2020 by Africa Centres for Disease Control and Prevention (Africa CDC), the World Health Organisation, and partners to strengthen national COVID-19 response coordination through public health emergency operations centres (PHEOC) utilizing continuous learning, mentorship, and networking. We present the lessons learned and reflection points. A multi-partner program coordination group was established to facilitate interventions' delivery including webinars and virtual community of practice (COP). We retrieved data from Africa CDC's program repository, synthesised major findings and describe these per thematic area. The virtual COP recorded 1,968 members and approximately 300 engagements in its initial three months. Fifty-six webinar sessions were held, providing 97 cumulative learning hours to 12,715 unique participants. Zoom data showed a return rate of 85%; 67% of webinar attendees were from Africa, and about 26 interactions occurred between participants and facilitators per session. Of 4,084 (44%) participants responding to post-session surveys, over 95% rated the topics as being relevant to their work and contributing to improving their understanding of PHEOC operationalisation. In addition, 95% agreed that the simplicity of the training delivery encouraged a greater number of public health staff to participate and spread lessons from it to their own networks. This just-in-time, progressively adaptive multi-faceted learning and knowledge management approach in Africa, with a consequential global audience at the peak of the COVID-19 pandemic, served its intended audience, had a high number of participants from Africa and received greatly satisfactory feedback.

Performance investigation on soil disinfection with a compound parabolic concentrating solar collector system

Soil disinfection is a necessary step in solar greenhouses because of the soil borne diseases and pests caused by the continuous cultivation. However, the traditional physical soil disinfection methods lead to high energy consumption and high carbon emissions, chemical soil disinfection methods cause great soil pollution. Therefore, this study proposed a novel soil disinfection system that can avoid soil pollution and achieve solar-powered physical disinfection of planting soil. The proposed system collects solar energy with the trough compound parabolic concentrating solar collector system. The collected solar heat is continuously delivered by airflow to the heat exchange pipes buried in the soil. As a result, the soil temperature can be raised to the required level for a certain period to suppress the growth of weeds and kill pests and pathogenic bacteria. In this study, the variation trend of soil temperature in the actual greenhouse was measured in the field and compared with the calculation results. After 5 consecutive sunny days of continuous operation of the solar collector system, the maximum soil temperature on the surface, at the depth of 0.15 m and 0.3 m were 59 °C, 48.6 °C, and 43.4 °C, respectively. The duration of soil at a certain temperature can also reflect the disinfection effect, and the longest cumulative hours with the soil temperature at a depth of 0.15 m above 37 °C was 107.27 h. At the same time, the average microbial biomass carbon and the microbial biomass nitrogen decreased by 11.04 % and 8.56 %, respectively. Furthermore, the payback period of the system is 1.97 years and the greenhouse gas emissions can be reduced by about 410.82 kg CO2, 1.33 kg SO2, and 1.16 kg NOx every year. The research results indicate that this novel method of soil disinfection is feasible, which can improve soil temperature and achieve the purpose of soil disinfection. This study can provide a reference for green and low-carbon soil disinfection in solar greenhouses.

How Does Environmental Temperature Affect Farmworkers' Work Rates in the California Heat Illness Prevention Study?

Estimate the association between environmental temperature (wet bulb globe temperature [WBGT]) and work rate over the course of a workday. Repeated-measures regression was used to identify characteristics impacting work rate in a cross-sectional study of Latino farmworkers. Minute-by-minute work rate (measured by accelerometer) and WBGT were averaged over 15-minute intervals. Work rate decreased by 4.34 (95% confidence interval [CI], -7.09 to -1.59) counts per minute per degree Celsius WBGT in the previous 15-minute interval. Cumulative quarter hours worked (2.13; 95% CI, 0.82 to 3.45), age (-3.64; 95% CI, -4.50 to -2.79), and dehydration at the end of workday (51.37; 95% CI, 19.24 to 83.50) were associated with counts per minute as were gender, pay type (piece rate vs hourly) and body mass index ≥25 kg/m 2 . The effects of pay type and body mass index were modified by gender. Increased temperature was associated with a decrease in work rate.

Performance of Hourly Rainfall Simulations using WRF Meteorological Model for Calculation of Streamflow to Ta Trach Reservoir During 2020 Flood Season

More and more extreme weather events are frequently observed in Thua Thien Hue province in recent years, especially in 2020. Only 7 days from October 6-12, 2020, total rainfall measured at Thuong Nhat station is approximately 1900 mm, accounting for more than 50% of the total annual rainfall. So, it is necessary to ensure the effective operation for Ta Trach reservoir, a large reservoir with a basin area of ​​717 km2 in Thua Thien Hue. This study is initially to clarify the performance of hourly rainfall simulations and streamflow to Ta Trach reservoir using WRF and HEC-HMS hydro-meteorological models during the 2020 flood season, respectively. The results showed that on the scale of daily, the correlation between simulated and measured rainfall is quite good, most of the stations could be reached about 0,8. On the scale of hourly, these figures are about 0,5 and the trend of cumulative hourly rainfall simulated is consistent with measured values. Especially, the trend of simulated streamflow using directly hourly rainfall from WRF model to Ta Trach reservoir is consistent with the measurement streamflow although the errors are still seen to extent with the NASH index of about 0,65.

Estimating Yield and Economic Losses Induced by Ozone Exposure in South China Based on Full-Coverage Surface Ozone Reanalysis Data and High-Resolution Rice Maps

Surface ozone (O3) pollution is an emerging environmental abiotic stress that poses substantial risks to crop yield losses and food security worldwide, and especially in China. However, the O3-induced detrimental effects on double-season rice have rarely been investigated at large scales and over relatively long temporal spans. In this study, we estimated the crop production reductions and associated economic losses for double-season rice across southern China during 2013–2019, using a high spatial resolution surface ozone reanalysis dataset and rice distribution maps, and county-level production data, in combination with a locally derived exposure-response function for rice. Results show that AOT40 (cumulative hourly O3 exposure above 40 ppb) presented generally increasing trends over growing seasons in 2013–2019, spanning from 4.0 to 7.1 ppm h and 6.1 to 10.5 ppm h for double-early rice and double-late rice, respectively. Moreover, O3-induced relative yield losses ranged from 4.0% to 6.6% for double-early rice and 6.3% to 11.1% for double-late rice. Over the seven years, ambient O3 exposure resulted in crop production losses of 1951.5 × 104 tons and economic losses of 8,081.03 million USD in total. To combat the O3-induced agricultural risks, measures such as stringent precursors emission reductions and breeding O3-resistant cultivars should be continuously implemented in the future.

CO2-free hydrogen production via microwave-driven methane pyrolysis

Hydrogen will play an integral role in achieving net-zero emissions by 2050. Many studies have been focusing on green hydrogen, but this method is highly electricity intensive. Alternatively, methane pyrolysis can produce hydrogen without direct CO2 emissions and with modest electricity inputs, serving as a bridge from fossil fuels to renewable energies. Microwaves are an efficient method of adding the required energy for this endothermic reaction. This study introduces a new method of CO2-free hydrogen production via non-plasma methane pyrolysis using microwaves and carbon products of this process. Carbon particles in the fluidized bed absorb microwave energy and create a hot medium (>1200 °C) in contact with flowing methane. As a result, methane decomposes into hydrogen and solid carbon achieving over 90% hydrogen selectivity with ∼500 cumulative hours of experiments This modular pyrolysis system can be built anywhere with access to natural gas and electricity, enabling distributed hydrogen production.

Electrophysiology lab efficiency comparison between cryoballoon and point-by-point radiofrequency ablation: a German sub-analysis of the FREEZE Cohort study

BackgroundPulmonary vein isolation (PVI) is recommended to treat paroxysmal and persistent atrial fibrillation (AF). This analysis aimed to assess the hospital efficiency of single-shot cryoballoon ablation (CBA) and point-by-point radiofrequency ablation (RFA).MethodsThe discrete event simulation used PVI procedure times from the FREEZE Cohort study to establish the electrophysiology (EP) lab occupancy time. 1000 EP lab days were simulated according to an illustrative German hospital, including 3 PVI cases per day using CBA at one site and RFA at the other.ResultsThe analysis included 1560 CBA patients and 1344 RFA patients from the FREEZE Cohort. Some baseline patients’ characteristics were different between groups (age, AF type, and some concomitant diseases), without being statistically associated to ablation procedure time. Mean procedure time was 122.2 ± 39.4 min for CBA and 160.3 ± 53.5 min for RFA (p < 0.0001). RFA was associated with a more than five-fold increase of cumulative overtime compared to CBA over the simulated period (1285 h with RFA and 253 h with CBA). 70.7% of RFA lab days included overtime versus 25.7% for CBA. CBA was associated with more days with an additional hour at the end of the EP lab shift compared to RFA (47.8% vs 11.5% days with one hour left, respectively).ConclusionCBA is faster and more predictable than point-by-point RFA, and enables improvements in EP lab efficiency, including: fewer cumulative overtime hours, more days where overtime is avoided and more days with remaining time for the staff or for any EP lab usage.Clinical trial registration NCT01360008 (first registration 25/05/2011).

Analysis of Multiyear Blowing Snow Occurrences in the French Alps

Abstract Wind-driven snow transport has important implications for spatial–temporal heterogeneity of snow distribution and snowpack evolution in mountainous areas, such as the French Alps. Due to the paucity of near-surface observations, our knowledge on the spatiotemporal variability of blowing snow occurrences is rather limited. Based on multiyear in situ observations, the spatial–temporal variability in the occurrence of blowing snow events in the French Alps was presented to investigate potential links with ambient meteorological conditions. Statistical analysis of the observations demonstrates that blowing snow events are frequently observed with substantial spatiotemporal variability. Most stations experienced snow transport one out of every five days throughout winter, and the corresponding cumulative hours with blowing snow occurrence accounted for 8% of the month in winter. Blowing snow events generally last 4–8 h in winter and early spring. The likelihood of blowing snow occurrences increases with wind speed but with divergent patterns across snow types. The frequency of blowing snow occurrences with concurrent snowfall is substantially higher than that without concurrent snowfall, although high spatiotemporal variability was found. The considerable variation in snow transport frequency can be explained by contrasting meteorological conditions, local climate, snowpack properties, and topography (elevation and aspect). The temperature-based empirical scheme failed to recognize individual occurrence of blowing snow events because of the significantly overestimated threshold wind speeds, highlighting the importance of validation using in situ observations. Our results contribute to the understanding of spatiotemporal occurrence of blowing snow events and facilitate the development of blowing snow models.

Too Much or Nothing at All: Racialized Administrative Burdens and Higher Education Policy Communication in Texas

ABSTRACT Several states, including Texas, have implemented an “excess semester credit hours (ESCH)” policy. State ESCH policies assess a fee to students at public institutions when they exceed a set number of lifetime cumulative credit hours (e.g. students with more than the 120 credit hours needed for a bachelor’s degree). In this article, we investigate a case study of Texas public institutions’ communication of state ESCH policies. We analyze 119 documents collected from November 2019 to April 2020 to conduct a deductive content analysis of the websites using the theory of racialized administrative burdens. We did find that institutions frequently attended by students of color, such as two-year institutions and HBCUs, were the least likely to have information about the ESCH policy.

The optimisation of rapeseed yield and growth duration through adaptive crop management in climate change: evidence from China

Crop yield is influenced by plant growth and development; both are affected by climatic variables and crop management practices. Therefore, understanding the effects of climate variables and management practices on rapeseed (Brassica napus L.) yield and growth duration (GD) is essential for developing strategies for agricultural systems based on changing climatic conditions. Thus, we quantified the respective contributions of climate change and crop management to rapeseed yield and GD between 2008 and 2019 in China using a first-difference multivariate regression model. Our results showed that: i) based on observed rapeseed yield and phenological data, the average planting date was delayed by –1.1 to 9.5 days decade–1, the average maturity date was advanced by 4.4 to 9.9 days decade–1, the average GD was shortened by 6.0 to 19.6 days decade–1 and the average yield increased by 12.82 to 61.5 kg ha–1 year–1; ii) the relative contributions of climate change and crop management to winter rapeseed yield were changed from –20% to +39% and from +61% to +80%, respectively, and the relative contributions to GD were changed from –10% to +15% and from –85% to +97%, respectively; iii) among the three climatic factors considered in this study, the climatic factor that caused the most remarkable change in winter rapeseed yield and GD was different in different regions. Overall, compared with cumulative temperature, cumulative sunshine hours may be the most critical climate factor limiting rapeseed yield in the Yangtze River Basin, especially in the upper reaches of the Yangtze River. Our results suggest that stakeholders select highyielding cultivars to optimise crop management and adaptation strategies in different agroecological zones. Highlights - The growth duration of winter rapeseed was shortened, and the yield increased in most stations. - Crop management to changes in GD and yield of winter rapeseed was greater than the impact of climate change. - Cumulative sunshine hours may be the most critical climate factor limiting rapeseed yield in the Yangtze River Basin.

Rates of dehydration in hydrous, high-Fo, magmatic olivines

Natural olivine from the Etna Fall Stratified eruption (3930 BP) was dehydrated to determine hydrogen diffusivity. Dehydration was carried out in several time-steps, from 0.5 to 40 cumulative hours, in a 1 atm. furnace at 810 and 1000 °C. This starting material has high H2O concentration (∼50 ppm), high forsterite (Fo ∼ 90 %), and high fO2 (∼NNO + 1.2), reflecting characteristics of its host magma. H2O concentration was measured using Fourier transform infrared spectroscopy after each heating step. Spectral peaks were fit with Gaussian curves to determine the contribution from each H+ defect. Zonation profiles along each crystallographic direction were modelled using the ‘whole-block’ method to determine bulk and defect-specific H+ diffusivity.Our modelling reveals a common apparent diffusivity for all defects, which is faster along ([100]) than b ([010]) or c ([001]) by more than an order of magnitude. A common defect-specific diffusivity has not been found in experiments on pure forsterite, so it appears that the presence of Fe enables H+ from all defects to diffuse via the proton-polaron mechanism (supported by the observed anisotropy). However, the rates that we observe are slower than the proton-polaron mechanism, which supports the recent proposal by Ferriss et al. (2018) that the apparent diffusivity is rate-limited by reactions between H+ bound in defect sites and Fe2+. A coupled reaction and diffusion process may explain the observed decrease in diffusivity along a over time, as well as an apparent non-zero H2O concentration at the crystal edge. Both of these effects need to be considered when modelling H+ diffusion profiles to determine decompression rate – fixing the edge concentration to zero will underestimate the diffusion timescale.Arrhenius laws describing diffusion parallel to a (at the start and end of the experiments), b, and c are developed from the diffusivity at 810 and 1000 °C: Dastart=10-2.94exp-182000RT, Daend=10-4.63exp-154000RT, Db=10-2.35exp-243000RT,Dc=10-4.01exp-187000RT, where R is the gas constant 8.314 (J/mol K); T is the temperature (K), the units of the diffusivities (D) are in m2/s. A comparison of experimental dehydration studies on natural olivines reveals that the diffusivity during dehydration likely depends on how the olivine was experimentally hydrated. To avoid this experimental effect and understand the diffusivity operating during ascent in a volcanic conduit, crystals which are naturally hydrous (such as the Etna olivines in this study) are particularly useful. Despite some ambiguity in the literature owing to different experimental approaches, our results suggest that for the studied range of pressure and temperature, forsterite content is the major control on H+ diffusivity, while H2O concentration and the fO2 at which the crystal last equilibrated have a smaller effect within the ranges studied for magmatic olivines.

Heat Health Risk and Adaptability Assessments at the Subdistrict Scale in Metropolitan Beijing

Against the background of global climate change, the increasing heat health risk from the combined effect of changes in high temperature, exposure, vulnerability, and other factors has become a growing concern. Yet the low number of temperature observation stations is insufficient to represent the complex changes in urban heatwaves, and subdistrict-scale (town, township, neighborhood committee, and equivalent) heat health risk and adaptability assessments are still limited. In this study, we built daytime and nighttime high-temperature interpolation models supported by data from 225 meteorological stations in Beijing. The models performed well at interpolating the cumulative hours of high temperature and the interpolation quality at night was better than that during the day. We further established a methodological framework for heat health risk and adaptability assessments based on heat hazard, population exposure, social vulnerability, and adaptability at the subdistrict scale in Beijing. Our results show that the heat health risk hotspots were mainly located in the central urban area, with 81 hotspots during the day and 76 at night. The average value of the heat health risk index of urban areas was 5.60 times higher than that of suburban areas in the daytime, and 6.70 times higher than that of suburban areas in the night. Greater population density and higher intensity of heat hazards were the main reasons for the high risk in most heat health risk hotspots. Combined with a heat-adaptive-capacity evaluation for hotspot areas, this study suggests that 11 high-risk and low-adaptation subdistricts are priority areas for government action to reduce heat health risk in policy formulation and urban development.