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This research details a survey of current Taiwanese college students and their study habits, leisure reading, and internet use. In the current project, we surveyed students in the fall of 2015 (n=965). We found that the students studied less than three hours per week, read for pleasure about the same amount of time, but spent over twenty hours a week on the internet. Students are not following their professor's expectations. We conclude by discussing the implications for further research in this area.

Soil microplastic (MP) pollution is a growing global environmental issue leading to a series of ecosystem problems and functional losses. However, understanding the advances and trends in soil MP pollution research proved to be difficult based on individual studies. Herein, CiteSpace visualization analysis software was used to sort the literature obtained on soil MP research from the Web of Science (WoS) TM core collection database, and bibliometric analysis of publication volume, country/region, keywords and other information was conducted. Results showed that soil microplastics (MP) research had much lower publication volume than hydrological system MP research, and was still in its developing stage. However, the number of research hotspots in soil MP research increased continuously since 2018. Countries such as China, the United States, the Netherlands and Australia have published more papers in this field than other countries, and collaboration among research institutions is strong. The source, pollution status, analysis methods and toxic effects of MPs in soils are current research hotspots. In the future, the focus of MP research in terrestrial ecosystems should shift from ecotoxicology to the impact of MPs on ecosystems and earth system feedback. The bibliometric analysis results of this study can serve as a reference for in-depth studies of the pollution status of MPs in soils. For MP soil pollution research, cross-background, cross-institution, cross-country cooperation and cross-disciplinary roles should be encouraged to accelerate the growth and diversification of the field.

Pot and field trials were conducted to explore the combined effect of biochar (BC) with topdressing silicon (Si) on Cd uptake by rice and grain yield in Cd-contaminated paddy soil. The treatments, including BC applied before transplanting (TBC), topdressing Si applied in the soil at the jointing stage (JSi) and BC combined with topdressing Si (TBC + JSi), were designed in a complete random block, and treatment without application of BC and Si was used as a control (CK). Results showed that Cd concentration in milled rice treated with TBC + JSi was decreased by 34.62%, 22.73% and 10.53%, respectively, when compared to CK, TBC and JSi, with the concentration being only 0.17 mg·kg−1. At rice maturity, available Cd in the soil was reduced by 7.98% (TBC), 4.76% (JSi) and 6.02% (TBC + JSi) when compared with CK, while the concentrations of total Cd were 32.07% (TBC), 27.85% (JSi) and 35.44% (TBC + JSi) higher than CK. Moreover, BC and Si increased the Cd sequestrated by leaves markedly, especially for TBC + JSi, which was much higher than TBC and JSi. Therefore, the transfer of Cd from leaf to milled rice was greatly decreased by TBC + JSi. In addition, a synergy effect of TBC + JSi on rice yield was also found. Compared with CK, the grain yields of TBC, JSi and TBC+ JSi were increased by 8.35%, 8.20% and 18.74%, respectively. Nutrient contents in soil and rice plants were also elevated by the application of BC and Si to a certain extent; for example, the contents of nitrogen (N), phosphorus (P), potassium (K) and Si in soil treated with TBC + JSi were raised by 8.96–60.03% when compared with CK. Overall, the combined application of BC with topdressing Si not only increases soil nutrients significantly, promotes their uptake by rice and boosts grain yield, but also effectively inhibits Cd transfer and reduces its accumulation in rice, which ultimately guarantees milled rice security. These results also imply that the combined application of biochar with topdressing silicon might be considered as an effective agronomic measure to decrease the milled-rice Cd in Cd-contaminated paddy soil, which would guarantee food security.

In order to fully capture the substantive spatial effect, linear and varying coefficient effects of regressors, and space–time correlations of disturbances, this paper introduces a new fixed effects partially linear varying coefficient spatial autoregressive model (PLVCSARM) with disturbances correlated in space and time. Its profile quasi-maximum likelihood estimators (PQMLEs) are constructed. Under some mild conditions, the consistency and asymptotic normality of the PQMLEs are derived. Simulation results show that the proposed estimates perform well in finite sample cases. • A new fixed effects PLVCSARM with disturbances correlated in space and time is proposed for economic or financial space–time panel data. • This model can study the substantive spatial effect, linear and varying coefficient effects of regressors, space–time correlations of disturbances, and avoid "curse of dimensionality". • The constructed PQMLEs satisfy consistency and asymtotic normality, and perform well in finite sample cases. [ABSTRACT FROM AUTHOR]

Silicon (Si) is commonly applied as base-fertilizer or foliar-topdressing to palliate the uptake-translocation-accumulation of cadmium (Cd) in rice through Si–Cd antagonism. However, little is known about the fate of Cd in rice rhizosphere soil and its eco-environmental effects under different Si treatments. Here, systematic works had been carried out to elucidate the Cd species, soil properties, and environmental risks in rice rhizosphere driven by different Si soil-fertilization regimes including CK (without Si-addition), TSi (added before transplanting stage), JSi (added at jointing stage), and TJSi (split into two equal parts, added half before transplanting and another half at jointing stage). Results showed that TJSi outperformed the rest of fertilization regimes. The solid-phase-Cd concentrations treated with TSi, TJSi and JSi were increased by 4.18%, 5.73% and 3.41%, respectively, when compared to CK. The labile Cd (F1+F2) proportion of TJSi was reduced by 16.30%, 9.30% and 6.78%, respectively, when compared to CK, TSi, and JSi. Simultaneously, the liquid-phase-Cd concentration was appreciably suppressed by TJSi throughout the rice lifecycle, while TSi mainly abated Cd dissociation during the vegetative period, and JSi attenuated it during the grain-filling stage. The mobility factor of Cd treated with TJSi was the lowest, which was significantly lower than that of TSi (9.30%) and JSi (6.78%), respectively. Similarly, the oral exposure risk of TJSi was reduced by 4.43% and 32.53%; and the food-chain exposure risk of TJSi was decreased by 13.03% and 42.78%. Additionally, TJSi was the most effective in promoting enzyme activities and nutrient content in rhizosphere soil. Overall, TJSi is more positive and sustainable than TSi and JSi in reconstructing Cd-contaminated rhizosphere environments and abating the environmental risks of Cd. Agronomic practices in Cd-contaminated paddy soils can be informed by applying Si-fertilizer separately before transplanting and at jointing stage to achieve soil welfare and food security. The fertilization regime of TJSi had more positive and long-lasting rhizosphere effects than TSi and JSi on Cd species, soil functionality, and environmental risks. The immobilization of Cd in solid-phase of rice rhizosphere soil was enhanced by TJSi through converting the geochemical fractions of Cd and regulating its balance across the solid-liquid interface. The soil available nutrients (N, P, K and Si) of TJSi were increased higher than those of TSi and JSi as well as the stronger activities of soil enzymes such as PPO, POD, UE, and SC. Compared to TSi and JSi, the oral exposure risk to Cd treated by TJSi was reduced by 4.43% and 32.53%, respectively; and the food chain exposure risk to Cd was decreased by 13.03% and 42.78%, respectively. In conclusion, TJSi could be an effective and novel agronomic practice for the Cd immobilization, soil functionality promotion, and environmental risk reduction. [Display omitted] • A contrasting effect of Si application regimes on rice rhizosphere was assessed. • TJSi had the better effect on Cd immobilization in rice rhizosphere soil. • TJSi exerted a great passivation-driven efficiency on Cd species in rhizosphere. • The lowest environmental risk of Cd was achieved by TJSi. • TJSi improved soil attributes and reconstructed a safer rhizosphere. [ABSTRACT FROM AUTHOR]

Copyright of Global Media Journal: Canadian Edition is the property of Global Media Journal: Canadian Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Documentation & Bibliotheques is the property of Les Editions ASTED inc and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Documentation & Bibliotheques is the property of Les Editions ASTED inc and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Some previous works have focused on dose-response relationship between cocoa consumption and blood pressure in Caucasians. As black subjects have lower nitric oxide bioavailability, the aim of this work was to determine the dose-effect relation between cocoa and blood pressure in black Africans., Method: One hundred and thirty healthy black African males aged 18-30 were randomly assigned into four groups: three groups consuming 10 g, 5 g, or 2 g of cocoa powder daily for three weeks and one control group that did not consume cocoa. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured on day 1 (D1, before any subject consumed cocoa), D8, D15, and D22. Means of the parameters at each of the four visits and changes of the means were compared among the groups., Results: Significant decrease in SBP was noted in consumers of 10 g compared to controls in the 1st week, and compared to consumers of 2 g in the 2nd and 3rd weeks of follow-up. Means and changes of DBP were statistically similar among the four groups., Conclusion: Among our cohort, decrease in SBP was significantly greater in the heavy cocoa consumer group (10 g) compared to the low consumer group (2 g), but there was no statistically significant difference when compared with the intermediate consumer group (5 g). The dose-response relationship between cocoa consumption and changes in SBP was not linear. No relationship was found between cocoa consumption and DBP., (© 2021 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Background: In Caucasians, regular consumption of cocoa induces a drop in arterial blood pressure via an increase in nitric oxide (NO) production. However, black individuals have a different NO biodisponibility compared to Caucasians. The aim of this study was to determine, in black Africans, the physiological variations in arterial blood pressure among cocoa consumers., Method: In total, 49 male black African volunteers, aged between 18 and 30 years old, were randomized into two groups; those consuming 10 g of cocoa powder per day (1,680 mg of flavonoids per day) for 3 weeks (consumer group), and those not consuming cocoa (control group). Systolic (SBP) and diastolic blood pressures (DBP), and heart rate (HR) were measured in the morning on an empty stomach (fasting), on day (D) 1 (without cocoa), D8, D15, and D22. Data were collected by groups and by subgroups established according to the level of SBP, DBP, or HR on D1. The means and variations of the means (between D1 and the subsequent days) of the recorded parameters were calculated and compared between groups and between subgroups., Results: On D8, the variations in SBP in the consumer group were significantly different from the control group (-3.72 ± 6.01 versus 0.57 ± 6.66 mmHg; p = 0.02). Between the control and consumer subgroups according to SBP, no statistical difference in the means or variations in SBP was noted. On D8 and D22, the variations in the SBP of consumers with SBP ≥ 110 mmHg on D1 were significantly different from those of other consumers (D8: -6.55 ± 5.96 versus -1.1 ± 4.93 mmHg; p = 0.01; D22: -6.63 ± 7.77 versus 0.35 ± 5.58 mmHg; p = 0.01). In the subgroups with a DBP < 75 mmHg on D1, the mean DBP of the consumers was significantly lower than that of the controls on D8 (65 ± 5 versus 69 ± 6 mmHg; p = 0.03)., Conclusion: In young black African men living in Côte d'Ivoire, regular consumption of cocoa resulted in a decrease in SBP and DBP. The decrease in SBP appeared to be greater the higher the baseline SBP was., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Siransy-Balayssac, Ouattara, Ahiboh, Youzan, Gouh, Yao, Ehouman, Dah and Bogui.)

Introduction: Maximal voluntary ventilation (MVV) and flow expiratory volume in the first second (FEVı) are important spirometric parameters. They are both gender-dependent. However, estimating the MVV, which is widely practiced in cardiopulmonary function testing, by multiplying FEVı by a constant value (equal to MVV/FEVı ratio) does not seem to take this into account. The purpose of this study was to compare the MVV/FEVı ratio by gender among healthy young adults., Methods: This cross-sectional prospective study involved 67 medical sciences students, including 36 females of the same race, height, and age group. Their ventilatory function was assessed using a computerized spirometer, according to international recommendations. Pearson's test made it possible to correlate different spirometric parameters and linear regression was established between MVV and FEVı. The nonparametric Kruskal-Wallis test was used to compare the MVV/FEVı ratio between females and males. Comparisons by gender were made also between our data and previous prediction equations., Results: In both females and males, FEVı was the spirometric parameter with which MVV had the highest correlation (r = .91 in females, r = .63 in males). A comparison of the means of the MVV/FEVı ratio by gender showed a statistically significant (p < .005) decrease in females (35.68 vs. 38.87). The previous prediction equations showed statistically significant under and overestimation of MVV values when gender was not taken into account., Conclusion: For the same height, age, and race, the ratio MVV/FEVı was significantly lower for females. So, the use of a preset constant value in estimating the MVV without taking gender into account was methodologically questionable. This work, which could have clinical implications, would benefit from being confirmed in a larger population., (© 2020 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

In Africa, abnormal high blood pressure is common and affects young subjects. The risk of organ damage and mortality increases with blood pressure level. Therefore, the purpose of this study was to assess the blood pressure profile of a black African population aged between 18 and 30 years in Côte d'Ivoire. Five hundred fifty-one healthy black African students, men and women, with sedentary lifestyle, aged between 18 and 30 years were selected. Systolic (SBP) and diastolic (DBP) blood pressures and heart rate were recorded after 5 min of rest. Regression models were used to estimate the effects of age, gender, and body mass index (BMI) on SBP and DBP. Each increase of 1 year in age and 1 kg/m 2 of BMI is significantly associated, respectively, with an increase of 20% (p = .002) and 17% (p = .008) in the risk of having an SBP ≥ 130 mmHg. The same risk is 3.8 times greater for men than women (p = .01). Among subjects with SBP < 120 mmHg, men have an SBP 5.22 mmHg higher than women (p < .001). The increase in the age of 1 year is significantly correlated with a rise of 36% of having a DBP ≥ 85 mmHg (p = .0001). Also, in men population, the age increase of 1 year is associated with a rise of 41% of having a DBP ≥ 85 mmHg (p = .0001). Among young black African students aged between 18 and 30 years in Côte d'Ivoire, SBP is positively associated with male gender, age, and BMI. For DBP, it is only an increase with age., (© 2020 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Recent publications focusing on sleep-wake alternation, using actigraphic recordings in hunter-gatherers, stressed the existence of a potential effect of electricity availability on sleep habits. These reports prompted us to achieve a new analysis of the polysomnographic data already obtained in healthy African volunteers in equatorial Africa during two different investigations. Comparison of the 24-h polysomnographic sleep patterns were done between 9 volunteers sleeping in a laboratory in Abidjan (Abidjan cohort) and 11 villagers living in electricity-free bush villages (Sinfra cohort). Sleep was lighter in the villagers, with more stage 1 and less slow wave sleep (SWS). Latency to SWS was also shorter. Total sleep time, however, was not different between the two groups. There were no indications as to whether the observed differences were attributable to the availability of electrical power. Reactivity of human sleep structure to the environment was discussed in terms of multifactorial influences such as daylight length, temperature, humidity, electromagnetic field, time of sleep onset, thermoregulatory mechanisms, stress or anxiety., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Abstract The longer QT interval duration observed in women compared to men is usually attributed to sexual hormones. The aim of our study was to investigate, among black African women, the influence of hormonal variations during the menstrual cycle on the duration of the QT interval. Fourteen young black African women, healthy, sedentary, aged 24 ± 1.7 years, with a regular menstrual cycle (28 ± 1 days) were selected from 59 volunteers. At each phase of their menstrual cycle, menstrual 2.9 ± 0.6 days, follicular 13 ± 1.5 days, and luteal 23.1 ± 1.4 days, an electrocardiogram was performed in supine position after a resting period of 30 min, to measure QT interval duration. QT interval was corrected by Bazett's (QTcb) and Fridericia's (QTcf) formulae. Then, blood samples were obtained to measure estradiol, progesterone, and serum electrolytes (K(+), Ca(2+), Mg(2+)). There was no significant difference in uncorrected QT intervals between the three phases of the menstrual cycle. It was the same for QTcb and QTcf. Moreover, during the menstrual cycle, we did not observe any correlation between each QT, QTcb, QTcf, and estradiol levels which raised during the follicular phase (356.61 ± 160.77 pg/mL) and progesterone levels which raised during the luteal phase (16.38 ± 5.88 ng/mL). Finally, the method of Bland and Altman demonstrated that the corrections of QT by Bazett and Fridericia formulae were not interchangeable. The results of this study showed that high levels of estradiol and progesterone in young black African women did not influence the QT, QTcb and QTcf intervals duration during the menstrual cycle.

Very few studies have investigated the effects of exercise on the biological parameters involved in vaso-occlusive events in sickle cell anaemia (SCA). The aim of this study was to test how a mild-moderate endurance exercise modulates oxidative stress, nitric oxide bioavailability and endothelial activation in SCA patients and healthy individuals. Eleven patients with SCA and 15 healthy subjects completed a 20-min duration submaximal cycling exercise at ≈45 Watts. Plasma markers of oxidative stress, antioxidant activity, endothelial activation and nitric oxide bioavailability were investigated before and after the exercise. Nitric oxide levels, anti-oxidant capacity, soluble (s)E-selectin and sP-selectin did not change in response to this exercise. Except for the malondialdehyde levels, which increased in the two groups, the other markers of oxidative stress remained unchanged in both groups in response to exercise. Soluble vascular cell adhesion molecule 1 levels were increased at the end of exercise in both groups. sL-selectin decreased and soluble intercellular adhesion molecule 1 increased with exercise in SCA patients only. The present data suggest that patients with SCA may undertake mild-moderate physical activities without any acute clinical complications, but care should be taken because oxidative stress and endothelial activation significantly increased in some patients., (© 2013 John Wiley & Sons Ltd.)