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1.
Environ Monit Assess ; 195(12): 1550, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030894

RESUMO

Reservoir cascade systems have attracted the attention of scientists worldwide. The present study investigates the cascade of five reservoirs (R1, R2, R3, R4, and R5) along a 192-km water channel system located in the state of Ceará, in the Brazilian semiarid region. This cascade system was implemented in 2012 to promote water availability and security to the capital of Ceará and the strategic industry and port complex of the region. However, these reservoirs have faced a progressive degradation of water quality, which has resulted in intense eutrophication and high-water treatment costs. The study evaluates the dynamics of water quality from 2013 to 2021 along this reservoir cascade (from R1 to R5). The results revealed that water quality did not improve along the cascade system, differently from previous studies on reservoirs interconnected by natural rivers. This was attributed to the low water residence time and low capacity of pollutant removal along the man-made water channel system, as well as to the high internal phosphorus loads of the reservoirs. Multiple regression models involving the explanatory variables of total phosphorus, total nitrogen, chlorophyll-a, cyanobacteria, transparency, rainfall, and volume from upstream reservoirs were obtained to determine total phosphorus concentration in downstream reservoirs, considering different combinations of reservoir pairs in the cascade and different time delays. A clear trend of R2 decline with the distance between the upstream and downstream reservoirs was observed. For example, the R2 values for the correlations adjusted between R1 and R2 (48 km), R1 and R3 (172 km), R1 and R4 (178 km), and R1 and R5 (192 km) were 0.66, 0.32, 0.22, and 0.12, respectively. On the other hand, the adoption of time delays of the order of the cumulative residence times of the reservoirs promoted a significant improvement in the R2 values. For instance, the best correlation adjusted between R1 and R5 improved from R2 = 0.12 to 0.69 by considering a time delay of 21 months. This suggests that previous data from upstream reservoirs can be used to predict current and future total phosphorus concentration in downstream reservoirs. The results from this study are important to better understand the spatiotemporal dynamics of water quality in reservoir cascade systems and thus improve water resources management, especially in drylands.


Assuntos
Aquaporinas , Monitoramento Ambiental , China , Clorofila A , Monitoramento Ambiental/métodos , Eutrofização , Nitrogênio/análise , Fósforo/análise , Qualidade da Água
2.
J Thorac Dis ; 16(7): 4584-4596, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39144329

RESUMO

Background: Cardiovascular surgeries often require deep hypothermic circulatory arrest and cardiopulmonary bypass (CPB), which can disrupt blood clotting and lead to excessive bleeding. Traditional treatments involve transfusing blood and blood products, which can have adverse effects and place significant strain on the global blood supply. Research suggests that autologous platelet-rich plasmapheresis (aPRP) may reduce the need for transfusions by preserving blood components. However, the impact of aPRP on postoperative blood loss and clinical outcomes in cardiovascular surgery remains controversial. This study aimed to examine the effects of aPRP on postoperative blood loss and recovery in patients undergoing heart valve surgery. Methods: A total of 183 patients were divided into either aPRP or control groups. The aPRP group received aPRP before CPB, whereas the control group did not. The primary endpoint was postoperative bleeding between the groups. The secondary endpoints were postoperative bleeding risk factors and clinical outcome assessment. Logistic regression analysis with covariate adjustment was used to calculate these risk factors. Results: A total of 76 patients (41.5%) in the aPRP group and 107 patients (58.5%) in the control group were included in the analysis. No significant difference was found in the occurrence of postoperative bleeding [odds ratio (OR) =0.53, 95% confidence interval (CI): 0.28-1.00, P=0.05], and the aPRP group had fewer complications than the controls (OR =0.28, 95% CI: 0.10-0.68, P=0.009). However, after adjusting for the New York Heart Association (NYHA) classification, diabetes, arrhythmology, mean activated clotting time (ACTmean), CPB, bleeding, thoracotomy, and body mass index (BMI), there was a significant difference in postoperative bleeding (adjusted OR =0.47, 95% CI: 0.22-0.98, P=0.04) and complications (adjusted OR =0.23, 95% CI: 0.07-0.64, P=0.008) between the two groups. Conclusions: Preoperative aPRP can improve postoperative outcomes and reduce complications in patients undergoing heart valve surgery.

3.
Behav Sci (Basel) ; 13(5)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37232665

RESUMO

Drawing on Wigfield and Eccles's motivational theory, which is acclaimed for explaining individual behavioral intentions, this study investigated the extent to which different forms of motivation (i.e., self-efficacy, task value, and intrinsic and extrinsic motivations) predicted student behavioral feedback engagement (i.e., action on teacher feedback and feedback seeking) in English learning. The participants were 276 male and female students who were enrolled in a second-year full-time English language and literature program at two Chinese universities. Multiple regression analyses showed that task value emerged as the only motivational variable that significantly predicted both students' action on teacher feedback and feedback seeking. Intrinsic motivation significantly predicted action on teacher feedback, whereas extrinsic motivation and self-efficacy significantly predicted feedback seeking. Pedagogical implications for endeavors to support students in their engagement with feedback in learning English as a foreign language in China are discussed.

4.
Front Psychol ; 12: 664367, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34163407

RESUMO

BACKGROUND: As with cognitive function, the ability to recognize emotions changes with age. In the literature regarding the relationship between recognition of emotion and cognitive function during aging, the effects of predictors such as aging, emotional state, and cognitive domains on emotion recognition are unclear. This study was performed to clarify the cognitive functions underlying recognition of emotional facial expressions, and to evaluate the effects of depressive mood on recognition of emotion in elderly subjects, as well as to reproduce the effects of aging on the recognition of emotional facial expressions. MATERIALS AND METHODS: A total of 26 young (mean age = 20.9 years) and 30 elderly subjects (71.6 years) participated in the study. All subjects participated in face perception, face matching, emotion matching, and emotion selection tasks. In addition, elderly subjects were administered a multicomponent cognitive test: the Neurobehavioral Cognitive Status Examination (Cognistat) and the Geriatric Depression Scale-Short Version. We analyzed these factors using multiple linear regression. RESULTS: There were no significant differences between the two groups in the face perception task, but in the face matching, emotion matching, and emotion selection tasks, elderly subjects showed significantly poorer performance. Among elderly subjects, multiple regression analyses showed that performance on the emotion matching task was predicted by age, emotional status, and cognitive function, but paradoxical relationships were observed between recognition of emotional faces and some verbal functions. In addition, 47% of elderly participants showed cognitive decline in one or more domains, although all of them had total Cognistat scores above the cutoff. CONCLUSION: It might be crucial to consider preclinical pathological changes such as mild cognitive impairment when testing for age effects in elderly populations.

5.
Clin Ophthalmol ; 15: 3557-3562, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34465976

RESUMO

PURPOSE: Patients with polypoidal choroidal vasculopathy (PCV) may develop large submacular hemorrhages (SMHs), which may result in severe visual loss. This study was performed to determine the visual outcomes and prognostic factors of large SMHs secondary to PCV. PATIENTS AND METHODS: We retrospectively reviewed the medical records of patients diagnosed with PCV who developed a large SMH. The best-corrected visual acuity (BCVA) data were collected at the SMH development, 1 month, 1 year after the SMH development, and at the final visit. Patients' medical information also were collected and included age, gender, systemic hypertension, current regular use of an anticoagulant or antiplatelet medication, the initial area of the SMH, breakthrough vitreous hemorrhage, ocular treatment, and fellow eye status. Univariate and multiple regression analyses were performed to determine the prognostic factors for the BCVA 1 year after the development of large SMHs. RESULTS: Thirty eyes of 29 patients were included in this study. The mean area of the SMHs at the development was 17.0 disc areas. The mean follow-up period after the development of SMHs was 53.5 months. The mean BCVA at the development, 1 month, and 1 year after the development, and at the final visit were 20/151, 20/263, 20/138, and 20/152, respectively. Multiple regression analyses indicated that a SMH 20 disc areas or larger was a significant negative factor, and the BCVA 1 month after the development was a significant positive factor affecting the BCVA 1 year after the development of large SMHs. CONCLUSION: The increase in the initial area of SMH was correlated inversely with the BCVA 1 year after the development of SMH. The BCVA 1 month after the development may predict the BCVA 1 year after the development of a large SMH.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32764524

RESUMO

A healthy lifestyle and regular physical activity are highly recommended for older adults. However, there has been limited research into testing lifestyle intervention effects on physical activity in older adults with hypertension. The purpose of this study was to assess the association of lifestyle intervention effects with physical activity and blood pressure in older adults with hypertension, accounting for social support and perceived stress as control variables. This study performed a secondary analysis of a two-arm randomized controlled trial. A total of 196 participants were randomly assigned to a six-month lifestyle intervention group or a control group. Hierarchical multiple regression analyses demonstrated that lifestyle intervention effects were not significantly associated with improvements in physical activity and blood pressure, but the final regression models were statistically significant (all p < 0.001). The result revealed that only physical activity frequency at baseline was significantly related to improvement in physical activity. Systolic blood pressure (SBP) at baseline and monthly income were significantly associated with change in SBP, while age and diastolic blood pressure (DBP) at baseline were significantly related to change in DBP. The findings provide empirical evidence for developing and optimizing lifestyle interventions for future research and clinical practice in this population.


Assuntos
Hipertensão , Vida Independente , Estilo de Vida , Idoso , Pressão Sanguínea , California/epidemiologia , Exercício Físico , Feminino , Humanos , Hipertensão/prevenção & controle , Masculino
7.
Bioresour Technol ; 206: 23-35, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26836846

RESUMO

Methane production characteristics and chemical composition of 405 silages from 43 different crop species were examined using uniform laboratory methods, with the aim to characterise a wide range of crop feedstocks from energy crop rotations and to identify main parameters that influence biomass quality for biogas production. Methane formation was analysed from chopped and over 90 days ensiled crop biomass in batch anaerobic digestion tests without further pre-treatment. Lignin content of crop biomass was found to be the most significant explanatory variable for specific methane yields while the methane content and methane production rates were mainly affected by the content of nitrogen-free extracts and neutral detergent fibre, respectively. The accumulation of butyric acid and alcohols during the ensiling process had significant impact on specific methane yields and methane contents of crop silages. It is proposed that products of silage fermentation should be considered when evaluating crop silages for biogas production.


Assuntos
Biocombustíveis/análise , Produtos Agrícolas/química , Fermentação , Metano/análise , Biomassa , Lignina , Silagem/análise
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