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To reduce environmental pollution and reliance on fossil resources, polyethylene terephthalate as the most consumed synthetic polyester needs to be recycled effectively. However, the existing recycling methods cannot process colored or blended polyethylene terephthalate materials for upcycling. Here we report a new efficient method for acetolysis of waste polyethylene terephthalate into terephthalic acid and ethylene glycol diacetate in acetic acid. Since acetic acid can dissolve or decompose other components such as dyes, additives, blends, etc., Terephthalic acid can be crystallized out in a high-purity form. In addition, Ethylene glycol diacetate can be hydrolyzed to ethylene glycol or directly polymerized with terephthalic acid to form polyethylene terephthalate, completing the closed-loop recycling. Life cycle assessment shows that, compared with the existing commercialized chemical recycling methods, acetolysis offers a low-carbon pathway to achieve the full upcycling of waste polyethylene terephthalate.
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To evaluate the pollution level of toxic elements in edible mushrooms from Jilin Province, China, the lead, cadmium, mercury, and arsenic content present in them were monitored and evaluated. A total of 610 edible mushroom samples, including fresh and dried, were collected from nine cities in the Jilin Province. The concentrations of lead, cadmium, mercury, and arsenic ranged from 0.007 to 3.31, 0.006 to 48.52, 0.003 to 0.56, and 0.008 to 57.34 mg/kg, respectively, in dried samples, and 0.007 to 0.06, 0.006 to 0.17, 0.003 to 0.06, and 0.008 to 0.12 mg/kg, respectively, in fresh samples. The concentration of cadmium and arsenic exceeded the standard (Cd ≤ 0.2 mg/kg, Cd of Lentinus edodes ≤ 0.5 mg/kg, and As ≤ 0.5 mg/kg) in some mushroom samples. The bioconcentration levels of lead, cadmium, mercury, and arsenic depended on the edible mushroom species, environment, and the physicochemical properties of lead, cadmium, mercury, and arsenic. The results of the single factor pollution index, a method used to calculate the level of single elements in substances, showed that all edible mushrooms were at the level of unpolluted except Tricholoma matsutake and Pleurotus eryngii. The comprehensive factor (P) for T. matsutake was 1.093. The comprehensive factor pollution index, a method used to calculate the level of combined mixture in substances, was in the unpolluted level, except for T. matsutake. The pollution index results showed that cadmium and arsenic concentrations were lightly polluting in some mushroom samples. The health risk index for arsenic was the highest. Therefore, more attention should be paid to arsenic contamination in T. matsutake and P. eryngii in the Jilin Province, China. PRACTICAL APPLICATION: In this paper, we evaluated the contamination levels and associated safety issues of four toxic elements, lead, cadmium, mercury, and arsenic, in edible mushrooms. The results showed that cadmium and arsenic concentrations were lightly polluting in some mushroom samples.
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Agaricales , Arsênio , Contaminação de Alimentos , Metais Pesados , Medição de Risco , Agaricales/química , Arsênio/análise , Cádmio/análise , China , Contaminação de Alimentos/análise , Chumbo/análise , Mercúrio/análise , Metais Pesados/análiseRESUMO
The mediating effects of psychological resilience on quality of life among older adults were rarely examined empirically. Based on the literature on the relationship between psychological resilience and quality of life and the factors associated with psychological resilience among older adults, a theoretical model was proposed with the hypothesis that psychological resilience would mediate the relationships between both filial support and sense of community and life satisfaction among older adults. The research used a cross-sectional design. Non-probability sampling method was applied to recruit 418 community-dwelling older adults in two adjacent cities in Fujian, China in 2017. A face-to-face structured Chinese questionnaire was adopted to collect data. The structural equation modeling showed that psychological resilience mediated the relationships between both filial support and sense of community and life satisfaction. The findings confirmed the positive impacts of psychological resilience on older adults' life satisfaction and highlighted the importance of family and community contexts to older adults' psychological resilience and life satisfaction. Interventions and programmes that aim to promote filial support towards older adults and enhance their sense of community would contribute to both their psychological resilience and life satisfaction.
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Satisfação Pessoal , Qualidade de Vida/psicologia , Resiliência Psicológica , Apoio Social , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/psicologia , China , Estudos Transversais , Feminino , Humanos , Vida Independente/psicologia , Masculino , Índice de Gravidade de Doença , Inquéritos e QuestionáriosRESUMO
OBJECTIVES: To investigate the value of liver stiffness in rats with various degrees of hepatic sinusoidal obstruction syndrome (HSOS) induced by monocrotaline by comparing liver histopathologic findings. METHODS: Seventy rats were randomly divided into a control group (n = 10), a low-dose monocrotaline group (n = 30), and a high-dose monocrotaline group (n = 30). After successful modeling, the liver shear wave velocity (SWV) by Virtual Touch tissue imaging quantification (Siemens Medical Solutions, Mountain View, CA) and the alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin levels of the groups were obtained on days 3 and 5, and the intergroup differences were compared. Liver histopathologic characteristics were analyzed to evaluate the degrees of HSOS, and the scores were recorded. RESULTS: On days 3 and 5, the total bilirubin, AST, and ALT, levels and liver SWV in the low- and high-dose groups were elevated; the portal vein velocity (PVV) of these groups was decreased compared with the control group; and the high-dose rats showed higher serum AST and ALT levels than the low-dose rats. The high-dose rats had a lower PVV than the low-dose rats at day 3. The liver SWV values had significant correlations with the histologic score and PVV. In a multivariate analysis, the liver SWV (ß = 0.813; P < .001) was independently associated with the histopathologic score. CONCLUSIONS: Liver stiffness as measured by Virtual Touch tissue imaging quantification increases with the severity of HSOS and can be recommended as a marker for diagnosis and assessment of HSOS.
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Técnicas de Imagem por Elasticidade/métodos , Hepatopatia Veno-Oclusiva/diagnóstico por imagem , Hepatopatia Veno-Oclusiva/patologia , Animais , Modelos Animais de Doenças , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Ratos , Reprodutibilidade dos TestesRESUMO
PURPOSE: To investigate the impact of disease duration on the ocular surface during the course of type 2 diabetes mellitus compared with nondiabetic controls. METHODS: One hundred twenty diabetic patients were divided into three groups according to disease duration: less than 5 years, 5-10 years, and over 10 years. All eyes were imaged using a corneal topographer (Oculus Keratograph 5M). Tear film measurements and meibography were also recorded. Meibomian gland changes were scored from 0 to 6 (meiboscore). RESULTS: The noninvasive breakup time first (NIKBUT-1st) and noninvasive breakup time average (NIKBUT-avg) were significantly shorter in the over 10 years diabetic group compared with the control group (P=0.0056 and P=0.010, resp.). Tear meniscus height (TMH) was significantly lower in the over 10 years diabetic group compared with the control group (P=0.0016) and the 5 years group (P=0.0061). We also found that more patients in the over 10 years diabetic group showed bulbar and limbal hyperemia compared with the control group (bulbar hyperemia: P=0.049; limbal hyperemia: P=0.026). The meiboscore in the over 10 years diabetic group was significantly higher compared with the other three groups (P < 0.05). Bulbar hyperemia showed a significant negative correlation with NIKBUT-1st in the over 10 years diabetic group (r=-0.35 and P < 0.05). CONCLUSION: Ocular surface damage in long-term type 2 diabetes is more severe than that in patients with shorter disease duration.
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BACKGROUND: To evaluate the role of free-hand transperineal targeted prostate biopsy using multiparametric magnetic resonance imaging-transrectal ultrasound (mpMRI-TRUS) fusion in Chinese men with repeated biopsy. METHODS: A total of 101 consecutive patients suspicious of prostate cancer (PCa) at the mpMRI scan and with prior negative biopsy and elevated PSA values were prospectively recruited at two urological centers. Suspicious areas on mpMRI were defined and graded using PI-RADS score. Targeted biopsies (TB) were performed for each suspicious lesion and followed a 12-core systematic biopsy (SB). Results of biopsy pathology and whole-gland pathology at prostatectomy were analyzed and compared between TB and SB. The risk for biopsy positivity was assessed by univariate and multivariate logistic regression analysis. RESULTS: Fusion biopsy revealed PCa in 41 of 101 men (40.6%) and 25 (24.8%) were clinically significant. There was exact agreement between TB and SB in 74 (73.3%) men. TB diagnosed 36% more significant cancer than SB (22 vs 13 cases, P = 0.012). When TB were combined with SB, an additional 14 cases (34.1%) of mostly significant PCa (71.4%) were diagnosed (P = 0.036). TB had greater sensitivity and accuracy for significant cancer than SB in 26 men with whole-gland pathology after prostatectomy. PI-RADS score on mpMRI was the most powerful predictor of PCa and significant cancer. CONCLUSIONS: Free-hand transperineal TB guided with MRI-TRUS fusion imaging improves detection of clinical significant PCa in Chinese men with previously negative biopsy. PI-RADS score is a reliable predictor of PCa and significant cancer.
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Imageamento por Ressonância Magnética , Próstata/patologia , Neoplasias da Próstata/patologia , Ultrassonografia de Intervenção , Idoso , Humanos , Hidroxietilrutosídeo , Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Imagem Multimodal/métodos , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico por imagem , RetoRESUMO
While researchers are aware that a mix of Local Ecological Knowledge (LEK), community-based resource management institutions, and higher-level institutions and policies can facilitate pastoralists' adaptation to climate change, policy makers have been slow to understand these linkages. Two critical issues are to what extent these factors play a role, and how to enhance local adaptation through government support. We investigated these issues through a case study of two pastoral communities on the Tibetan Plateau in China employing an analytical framework to understand local climate adaptation processes. We concluded that LEK and community-based institutions improve adaptation outcomes for Tibetan pastoralists through shaping and mobilizing resource availability to reduce risks. Higher-level institutions and policies contribute by providing resources from outside communities. There are dynamic interrelationships among these factors that can lead to support, conflict, and fragmentation. Government policy could enhance local adaptation through improvement of supportive relationships among these factors. While central government policies allow only limited room for overt integration of local knowledge/institutions, local governments often have some flexibility to buffer conflicts. In addition, government policies to support market-based economic development have greatly benefited adaptation outcomes for pastoralists. Overall, in China, there are still questions over how to create innovative institutions that blend LEK and community-based institutions with government policy making.
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Criação de Animais Domésticos , Mudança Climática , Conservação dos Recursos Naturais , Política Ambiental , Relações Comunidade-Instituição , Humanos , Conhecimento , Pessoa de Meia-Idade , Formulação de Políticas , TibetRESUMO
By using a multilayer composite ab initio method ONION-G3B3, we calculated O-H bond dissociation enthalpies (BDEs) of 58 oximes that were measured experimentally. Experimental BDEs derived from thermal decomposition kinetics and calorimetric measurements were found to be consistent with the theory. However, the electrochemical method was found to give questionably high BDEs possibly due to errors in the measurement of pKa's or redox potentials. Subsequently, the performances of a variety of DFT functionals including B3LYP, B3P86, B3PW91, BHandH, BHandHLYP, BMK, PBE1PBE, MPW1KCIS, mPWPW91, MPW1B95, and MPW1K were tested to calculate oxime O-H BDEs, where ROBHandHLYP was found to be the most accurate. By using this method, we calculated O-H BDEs of over 140 oximes in a systematic fashion. All of the calculated O-H BDEs fell in the range from 76.8 to 89.8 kcal/mol. An amino group on the azomethine carbon was found to strengthen the O-H bond, whereas bulky alkyl substituents on oximes decreased O-H BDEs due to their large steric-strain-relieving effects in the process of O-H bond cleavage. Para substituents had little effect on the BDEs of benzaldoximes and phenyl methyl ketoximes. Finally, on the basis of a spin distribution calculation, aryl-, alkyl-, and carbonyl-substituted iminoxyl radicals were found to be sigma-radicals, whereas amino-substituted iminoxyl radicals were of pi-structure.
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Hidrogênio/química , Oximas/química , Oxigênio/química , TermodinâmicaRESUMO
N,O-Bidentate compounds were systematically evaluated as phosphine-free ligands for Pd-catalyzed C-C bond-formation reactions through kinetic measurements. Pd(quinoline-8-carboxylate)2 was identified as one of the most efficient, yet still low-priced, phosphine-free catalysts for Heck as well as Suzuki reactions of unactivated aryl bromides with high turnover numbers up to ca. 10,000.