Exertional rhabdomyolysis in newly enrolled cadets of a military academy.

INTRODUCTION/AIMS: Exertional rhabdomyolysis (ER) often occurs during prolonged intense exercise in hot environments, posing a threat to the health of military personnel. In this study we aimed to investigate possible risk factors for ER and provide further empirical data for prevention and clinical treatment strategies. METHODS: A retrospective investigation of 116 concurrent ER cases was conducted. Conditional logistic regression analyses were performed to assess the association between each potential risk (or protective) factor and ER. The clinical characteristics of the 71 hospitalized patients were analyzed descriptively. RESULTS: After screening, the following variables significantly increased the risk of ER: shorter length of service (recruits; odds ratios [OR], 7.49; 95% confidence interval [CI], 2.58-21.75); higher body mass index (BMI; OR, 1.14, 95% CI, 1.03-1.26); lack of physical exercise in the last half year (less than once per month; OR, 3.20; 95% CI, 1.08-9.44); and previous heat injury (OR, 2.94; 95% CI, 1.26-6.89). Frequent fruit consumption (OR, 0.57; 95% CI, 0.33-0.99), active hydration habit (OR, 0.37; 95% CI, 0.20-0.67), water replenishment of more than 2 L on the training day (OR, 0.15; 95% CI, 0.05-0.45), and water replenishment of at least 500 mL within 1 hour before training (OR, 0.33; 95% CI, 0.12-0.88) significantly decreased the risk of ER. Of the 71 hospitalized patients, 41 (57.7%) were diagnosed with hypokalemia on admission. DISCUSSION: In military training, emphasis should be placed on incremental adaptation training before more intense training, and close attention should be given to overweight and previously sedentary recruits. Fluid replenishment before exercise, increased fruit intake, and proper potassium supplementation may help prevent ER.

The Influence of Teacher-Student Interaction on the Effects of Online Learning: Based on a Serial Mediating Model.

During the COVID-19 pandemic, online education has become an important approach to learning in the information era and an important research topic in the field of educational technology as well as that of education in general. Teacher-student interaction in online education is an important factor affecting students' learning performance. This study employed a questionnaire survey to explore the influence of teacher-student interaction on learning effects in online education as well as the mediating role of psychological atmosphere and learning engagement. The study involved 398 college students studying at Chinese universities as the research object. Participants filled out a self-report questionnaire. The study found that (1) the level of teacher-student interaction positively affected students' learning effects (r = 0.649, p < 0.01). (2) The psychological atmosphere mediated the positive effect of the level of teacher-student interaction on learning effects with mediating effect value of 0.1248. (3) Learning engagement mediated the positive effect of teacher-student interaction on learning effects with a mediating effect value of 0.1539. (4) The psychological atmosphere and learning engagement play a chain-mediating role in the mechanism of teacher-student interaction affecting students' learning effects; that is, teacher-student interaction promotes students' learning engagement by creating a good psychological atmosphere, which, in turn, influences learning effects. The mediating effect value was 0.0403. The results indicate that teacher-student interaction not only directly affects students' learning effects but also influences students' learning effects through the mediating effect of the psychological atmosphere and learning engagement.

Remarkably High Thermoelectric Efficiencies of the Half-Heusler Compounds BXGa (X = Be, Mg, and Ca).

The thermoelectric materials with high values of the dimensionless figure of merit (ZT) are among the most important new energy resources. Too much attention has been paid to the search of high-ZT thermoelectric materials, and the one with ZT = 5 has been reported recently. Here, a remarkably high ZT = 7.38 is predicted for the n-type half-Heusler compound of BCaGa at 700 K. To understand the high-ZT behavior, we studied electronic properties of BXGa (X = Be, Mg, and Ca) with first-principles calculations based on the density functional theory. The stabilities of the structures of BXGa (X = Be, Mg, and Ca) are confirmed by phonon dispersion. The transport properties are determined by the semiclassical Boltzmann transport theory. We evaluate the relaxation time by using the deformation potential theory and the lattice thermal conductivity based on the elastic coefficients. The results demonstrate that such a high efficiency of BCaGa arises from the intrinsic coordination of the ultralow lattice and electronic thermal conductivity and the larger power factor at certain carrier concentration and temperature. The high n-type power factor originates from the large relaxation time, which results in a light, twofold degenerate conduction-band pocket at the Γ point. In contrast, the power factors of BBeGa and BMgGa are smaller because of their flat-and-dispersive valence band. It is expected that the remarkable results for BXGa could encourage more experimental and theoretical investigations to develop efficient thermoelectric materials with BXGa.

Early Departure, Early Revival: A ''Free From Care'' Account of Negative Temporal Discounting.

According to the positive temporal discounting theory and our relevant observations, when faced with future losses, people should, and do, prefer delayed negative events (e.g., deferring paying taxes, debts, or tickets), which can lead to substantial individual and societal costs. However, a counterexample has been identified and it appears to depart from the prediction of positive temporal discounting when faced with negative events. This study proposed and investigated the novel free from care account for the reverse preference. Results of five laboratory and field studies showed that students preferred an immediate negative event (i.e., an English oral exam) when "something tying one up" was imposed, in which coping with a distraction induced by such a situation could play a mediating role. In particular, the addition of "something tying one up" was found to be an effective behavioral nudge in terms of reliability and reproducibility and should be simple for potential users to follow. Specifically, the association between being tied up and undergoing a negative event immediately in the present studies mirrored the association between outgroup threat and intergroup cooperation in the Robbers Cave experiment.

Spatiotemporal Dynamics of Scrub Typhus Transmission in Mainland China, 2006-2014.

BACKGROUND: Scrub typhus is endemic in the Asia-Pacific region including China, and the number of reported cases has increased dramatically in the past decade. However, the spatial-temporal dynamics and the potential risk factors in transmission of scrub typhus in mainland China have yet to be characterized. OBJECTIVE: This study aims to explore the spatiotemporal dynamics of reported scrub typhus cases in mainland China between January 2006 and December 2014, to detect the location of high risk spatiotemporal clusters of scrub typhus cases, and identify the potential risk factors affecting the re-emergence of the disease. METHOD: Monthly cases of scrub typhus reported at the county level between 2006 and 2014 were obtained from the Chinese Center for Diseases Control and Prevention. Time-series analyses, spatiotemporal cluster analyses, and spatial scan statistics were used to explore the characteristics of the scrub typhus incidence. To explore the association between scrub typhus incidence and environmental variables panel Poisson regression analysis was conducted. RESULTS: During the time period between 2006 and 2014 a total of 54,558 scrub typhus cases were reported in mainland China, which grew exponentially. The majority of cases were reported each year between July and November, with peak incidence during October every year. The spatiotemporal dynamics of scrub typhus varied over the study period with high-risk clusters identified in southwest, southern, and middle-eastern part of China. Scrub typhus incidence was positively correlated with the percentage of shrub and meteorological variables including temperature and precipitation. CONCLUSIONS: The results of this study demonstrate areas in China that could be targeted with public health interventions to mitigate the growing threat of scrub typhus in the country.

Spatiotemporal Clustering Analysis and Risk Assessments of Human Cutaneous Anthrax in China, 2005-2012.

OBJECTIVE: To investigate the epidemic characteristics of human cutaneous anthrax (CA) in China, detect the spatiotemporal clusters at the county level for preemptive public health interventions, and evaluate the differences in the epidemiological characteristics within and outside clusters. METHODS: CA cases reported during 2005-2012 from the national surveillance system were evaluated at the county level using space-time scan statistic. Comparative analysis of the epidemic characteristics within and outside identified clusters was performed using using the χ2 test or Kruskal-Wallis test. RESULTS: The group of 30-39 years had the highest incidence of CA, and the fatality rate increased with age, with persons ≥70 years showing a fatality rate of 4.04%. Seasonality analysis showed that most of CA cases occurred between May/June and September/October of each year. The primary spatiotemporal cluster contained 19 counties from June 2006 to May 2010, and it was mainly located straddling the borders of Sichuan, Gansu, and Qinghai provinces. In these high-risk areas, CA cases were predominantly found among younger, local, males, shepherds, who were living on agriculture and stockbreeding and characterized with high morbidity, low mortality and a shorter period from illness onset to diagnosis. CONCLUSION: CA was geographically and persistently clustered in the Southwestern China during 2005-2012, with notable differences in the epidemic characteristics within and outside spatiotemporal clusters; this demonstrates the necessity for CA interventions such as enhanced surveillance, health education, mandatory and standard decontamination or disinfection procedures to be geographically targeted to the areas identified in this study.

Spatiotemporal transmission dynamics of hemorrhagic fever with renal syndrome in China, 2005-2012.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is a rodent-borne disease caused by many serotypes of hantaviruses. In China, HFRS has been recognized as a severe public health problem with 90% of the total reported cases in the world. This study describes the spatiotemporal dynamics of HFRS cases in China and identifies the regions, time, and populations at highest risk, which could help the planning and implementation of key preventative measures. METHODS: Data on all reported HFRS cases at the county level from January 2005 to December 2012 were collected from Chinese Center for Disease Control and Prevention. Geographic Information System-based spatiotemporal analyses including Local Indicators of Spatial Association and Kulldorff's space-time scan statistic were performed to detect local high-risk space-time clusters of HFRS in China. In addition, cases from high-risk and low-risk counties were compared to identify significant demographic differences. RESULTS: A total of 100,868 cases were reported during 2005-2012 in mainland China. There were significant variations in the spatiotemporal dynamics of HFRS. HFRS cases occurred most frequently in June, November, and December. There was a significant positive spatial autocorrelation of HFRS incidence during the study periods, with Moran's I values ranging from 0.46 to 0.56 (P<0.05). Several distinct HFRS cluster areas were identified, mainly concentrated in northeastern, central, and eastern of China. Compared with cases from low-risk areas, a higher proportion of cases were younger, non-farmer, and floating residents in high-risk counties. CONCLUSIONS: This study identified significant space-time clusters of HFRS in China during 2005-2012 indicating that preventative strategies for HFRS should be particularly focused on the northeastern, central, and eastern of China to achieve the most cost-effective outcomes.

Surface enhanced Raman spectroscopic studies on magnetic Fe3O4@AuAg alloy core-shell nanoparticles.

A facile approach has been developed to fabricate multifunctional Fe3O4@AuAg alloy core-shell nanoparticles, owning the magnetism of the core and the surface enhanced Raman spectroscopy (SERS) activities of the alloy shell. By changing the amount of HAuCl4 and AgNO3, Fe3O4@AuAg alloy nanoparticles with different component ratios of Au and Ag were successfully prepared. The surface plasmon resonance of the composition was linearly tuned in a wide range by varying the molar fraction of Ag and Au, suggesting the formation of AuAg alloy shell. SERS and magnetic enrichment effects were investigated by using thiophenol (TP) as the probe molecule. The SERS intensity was strongly dependent on the molar ratios of Au and Ag and the excitation line. Enrichment for the molecules with low concentration and on line SERS monitoring experiments were performed through combining the magnetism of the core and the SERS effect of the alloy shell. The results revealed that the magnetic enrichment efficiency was dramatically increased due to the strong magnetism of Fe3O4 core. In addition, the Fe3O4@AuAg nanoparticles were also used in the microfluidic chip to continuously detect different flowing solution in the channel. The detection time and amount of analyte were successfully decreased.

Association between hemorrhagic fever with renal syndrome epidemic and climate factors in Heilongjiang Province, China.

The purpose of this study was to quantify the relationship between climate variation and transmission of hemorrhagic fever with renal syndrome (HFRS) in Heilongjiang Province, a highly endemic area for HFRS in China. Monthly notified HFRS cases and climatic data for 2001-2009 in Heilongjiang Province were collected. Using a seasonal autoregressive integrated moving average model, we found that relative humidity with a one-month lag (ß = -0.010, P = 0.003) and a three-month lag (ß = 0.008, P = 0.003), maximum temperature with a two-month lag (ß = 0.082, P = 0.028), and southern oscillation index with a two-month lag (ß = -0.048, P = 0.019) were significantly associated with HFRS transmission. Our study also showed that predicted values expected under the seasonal autoregressive integrated moving average model were highly consistent with observed values (Adjusted R(2) = 83%, root mean squared error = 108). Thus, findings may help add to the knowledge gap of the role of climate factors in HFRS transmission in China and also assist national local health authorities in the development/refinement of a better strategy to prevent HFRS transmission.

Spatiotemporal patterns of Japanese encephalitis in China, 2002-2010.

OBJECTIVE: The aim of the study is to examine the spatiotemporal pattern of Japanese Encephalitis (JE) in mainland China during 2002-2010. Specific objectives of the study were to quantify the temporal variation in incidence of JE cases, to determine if clustering of JE cases exists, to detect high risk spatiotemporal clusters of JE cases and to provide evidence-based preventive suggestions to relevant stakeholders. METHODS: Monthly JE cases at the county level in mainland China during 2002-2010 were obtained from the China Information System for Diseases Control and Prevention (CISDCP). For the purpose of the analysis, JE case counts for nine years were aggregated into four temporal periods (2002; 2003-2005; 2006; and 2007-2010). Local Indicators of Spatial Association and spatial scan statistics were performed to detect and evaluate local high risk space-time clusters. RESULTS: JE incidence showed a decreasing trend from 2002 to 2005 but peaked in 2006, then fluctuated over the study period. Spatial cluster analysis detected high value clusters, mainly located in Southwestern China. Similarly, we identified a primary spatiotemporal cluster of JE in Southwestern China between July and August, with the geographical range of JE transmission increasing over the past years. CONCLUSION: JE in China is geographically clustered and its spatial extent dynamically changed during the last nine years in mainland China. This indicates that risk factors for JE infection are likely to be spatially heterogeneous. The results may assist national and local health authorities in the development/refinement of a better preventive strategy and increase the effectiveness of public health interventions against JE transmission.

[Interactive effects of light intensity and nitrogen supply on fraxinus mandshurica seedlings growth, biomass, and nitrogen allocation].

With sand culture in greenhouse, the responses of Fraxinus mandshurica seedlings growth, biomass, and N allocation to 2 levels of light intensity and 4 levels of N supply were studied. The results showed that under low light intensity, the seedlings shoot/root ratio (S/R) and net N uptake rate (NNUR) increased significantly (P < 0.01), but their relative growth rate (RGR) and net assimilation rate (NAR) had a significant decrease (P < 0.01). The biomass of root, stem, leaf, and total plant under low light was decreased by 36.8% (P < 0.01), 1.7%, 12.7% (P < 0.05) , and 24.3% (P < 0.01), respectively, and the N allocation to leaf increased but that to root was in adverse. At the two light levels, N supply had an obvious promotion effect on the seedlings growth, and the S/R and the N allocation to leaf were increased obviously with increasing N supply. Significant interactive effects of light and N supply were observed on the seedlings diameter, S/R, RGR, and biomass allocation.

[Physiological processes and major regulating factors of nitrogen uptake by plant roots].

Soil nitrogen (N) is one of the mineral elements absorbed in large amount by plant roots, while global change could affect its availability, and furthermore, affect the carbon (C) allocation in terrestrial ecosystem. Therefore, the study of plant root N uptake and regulation becomes an important issue in predicting the structure and function of ecosystem. In the biosphere, plants are exposed to different N forms, and long-term biological evolution and environmental adaptation resulted in a significant distinction of plant root N uptake regions and metabolic processes, as well as the regulation of the N uptake. However, plant has formed different mechanisms and strategies for N uptake, because of their living in the soil with dominant sole N form for generations. In this paper, the research advances on how plant root absorbs N and which factors control the N absorption processes were reviewed, with the biological availability of different soil N forms (nitrate, ammonium and organic N), N uptake regions in root, N loading and transport in xylem, and uptake mechanisms of different N forms emphasized. The signal regulation of N uptake and the effects of environmental factors were also considered. Several issues about the present researches on plant root N uptake were discussed.

[Soil respiration in temperate secondary forest and Larix gmelinii plantation in Northeast China].

With Li-6400-09 chamber, the soil respiration rate in adjacent stands of temperate secondary forest and Larix gmelinii plantation in Maoershan Mountain of Heilongjiang Province was measured from May to October, 2006. The results showed that similar to the variation of soil temperature, the daily pattern of soil respiration could be expressed as a one-humped curve. Over the study period, soil respiration rate varied from 0.43 to 7.26 micromol CO2 x m(-2) x s(-1) in secondary forest, and from 0.63 to 4.70 micromol CO2 x m(-2) x s(-1) in L. gmelinii plantation. The maximum soil respiration rate occurred from July to August, and the minimum in October. From May to August, soil respiration rate was obviously higher in secondary forest than in L. gmelinii plantation. The respiration rate of litter layer during the study period varied from -0.65 to 1.26 micromol CO2 x m(-2) x s(-1) in secondary forest, and from -0.43 to 0.47 micromol CO2 x m(-2 ) x s(-1) in L. gmelinii plantation. Soil respiration had a strong exponential correlation with soil temperature, especially the temperature at 5 cm depth. The Q10 value at 5 cm depth was 3.61 and 3.07, respectively in secondary forest and L. gmelinii plantation. There was a significant correlation between soil respiration and the soil water content at 10-20 cm depth in secondary forest, but less correlation was observed between them in L. gmelinii plantation.