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1.
Sci Total Environ ; 903: 166708, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37660809

RESUMO

Organophosphate esters (OPEs) have been used worldwide as organophosphate flame retardants (OPFRs) since brominated flame retardants (BFRs) were banned. Due to the toxicity of these OPEs, environmental concerns and ecological risks arose. However, there are still large gaps in the understanding of their toxicity to organisms and the mechanisms of toxicity. After collecting the existing toxicity information and obtaining molecular descriptors of OPEs, a partial least square (PLS) regression model was used in this study to quantify the structure-toxicity relationships of OPEs. Based on the regression results, the acute toxicity of the remaining OPEs lacking acute toxicity data was predicted, and the risk level of total common OPEs was classified. The acute toxicity of 15 chemicals was collected, and >1660 molecular structure descriptors were obtained. The cross-validation results of the partial least square regression indicated that two principal components met the regression requirements with the selected features, and the regression equations of these chemicals were generated with selected molecular descriptors. The influence of physicochemical properties, such as hydrophobicity/molecular weight, in traditional perception of OPE toxicity was not that obvious, and acute toxicity was mainly influenced by the autocorrelation coefficients. However, the regression results indicated that the correlation between autocorrelation coefficients calculated based on different physicochemical properties and toxicity was different. According to the prediction result based on PLS regression, CDP may pose a high risk and halogenated alkyl-substituted OPEs such as TCEP may be less toxic. The results of the present study may help inform the environmental management and risk assessment of emerging chemicals such as OPEs.

2.
Toxics ; 11(7)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37505523

RESUMO

Water quality criteria (WQC) for the protection of aquatic organisms mainly focus on the maximum threshold values of the pollutants that do not have harmful effects on aquatic organisms. The WQC value is the result obtained based on scientific experiments in the laboratory and data fitting extrapolation and is the limit of the threshold value of pollutants or other harmful factors in the water environment. Until now, many studies have been carried out on WQC for the protection of aquatic organisms internationally, and several countries have also issued their own relevant technical guidelines. Thus, the WQC method for the protection of aquatic organisms has been basically formed, with species sensitivity distribution (SSD) as the main method and the assessment factor (AF) as the auxiliary method. In addition, in terms of the case studies on WQC, many scholars have conducted relevant case studies on various pollutants. At the national level, several countries have also released WQC values for typical pollutants. This study systematically discusses the general situation, theoretical methodology and research progress of WQC for the protection of aquatic organisms, and deeply analyzes the key scientific issues that need to be considered in the research of WQC. Furthermore, combined with the specific characteristics of the emerging pollutants, some new ideas and directions for future WQC research for the protection of aquatic organisms are also proposed.

3.
IEEE Trans Pattern Anal Mach Intell ; 45(11): 13636-13652, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37467085

RESUMO

In this work, we explore neat yet effective Transformer-based frameworks for visual grounding. The previous methods generally address the core problem of visual grounding, i.e., multi-modal fusion and reasoning, with manually-designed mechanisms. Such heuristic designs are not only complicated but also make models easily overfit specific data distributions. To avoid this, we first propose TransVG, which establishes multi-modal correspondences by Transformers and localizes referred regions by directly regressing box coordinates. We empirically show that complicated fusion modules can be replaced by a simple stack of Transformer encoder layers with higher performance. However, the core fusion Transformer in TransVG is stand-alone against uni-modal encoders, and thus should be trained from scratch on limited visual grounding data, which makes it hard to be optimized and leads to sub-optimal performance. To this end, we further introduce TransVG++ to make two-fold improvements. For one thing, we upgrade our framework to a purely Transformer-based one by leveraging Vision Transformer (ViT) for vision feature encoding. For another, we devise Language Conditioned Vision Transformer that removes external fusion modules and reuses the uni-modal ViT for vision-language fusion at the intermediate layers. We conduct extensive experiments on five prevalent datasets, and report a series of state-of-the-art records.

4.
Toxics ; 11(5)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37235215

RESUMO

A total of 34 antibiotics from five major classes of antibiotics, including macrolides, sulfonamides, quinolones, tetracyclines and chloramphenicol, were considered as contaminants, considering the Yellow River Estuary as the study area. The distribution, sources and ecological risks of typical antibiotics in the Yellow River Estuary were investigated using an optimized solid-phase extraction pre-treatment and an Agilent 6410B tandem triple-quadrupole liquid chromatography-mass spectrometer for antibiotic detection. The results show that antibiotics were widely present in the water bodies of the Yellow River Estuary, with 14 antibiotics detected to varying degrees, including a high detection rate for lincomycin hydrochloride. Farming wastewater and domestic sewage were the primary sources of antibiotics in the Yellow River Estuary. The distribution characteristics of antibiotics in the study area were linked to the development of farming and social activities. The ecological risk evaluation of 14 antibiotics in the Yellow River Estuary watershed showed that clarithromycin and doxycycline hydrochloride were present at medium-risk levels, and lincomycin hydrochloride, sulfamethoxazole, methomyl, oxifloxacin, enrofloxacin, sulfadiazine, roxithromycin, sulfapyridine, sulfadiazine and ciprofloxacin were present at low-risk levels in the samples collected from water bodies of the Yellow River Estuary. This study provides novel, beneficial information for the assessment of the ecological risk presented by antibiotics in the Yellow River Estuary water bodies and provides a scientific basis for future antibiotic pollution control in the Yellow River Basin.

5.
J Pers Soc Psychol ; 125(3): 471-495, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37126053

RESUMO

Social science research has highlighted "honor" as a central value driving social behavior in Mediterranean societies, which requires individuals to develop and protect a sense of their personal self-worth and their social reputation, through assertiveness, competitiveness, and retaliation in the face of threats. We predicted that members of Mediterranean societies may exhibit a distinctive combination of independent and interdependent social orientation, self-construal, and cognitive style, compared to more commonly studied East Asian and Anglo-Western cultural groups. We compared participants from eight Mediterranean societies (Spain, Italy, Greece, Turkey, Cyprus [Turkish Cypriot and Greek Cypriot communities], Lebanon, Egypt) to participants from East Asian (Korea, Japan) and Anglo-Western (the United Kingdom, the United States) societies, using six implicit social orientation indicators, an eight-dimensional self-construal scale, and four cognitive style indicators. Compared with both East Asian and Anglo-Western samples, samples from Mediterranean societies distinctively emphasized several forms of independence (relative intensity of disengaging [vs. engaging] emotions, happiness based on disengaging [vs. engaging] emotions, dispositional [vs. situational] attribution style, self-construal as different from others, self-directed, self-reliant, self-expressive, and consistent) and interdependence (closeness to in-group [vs. out-group] members, self-construal as connected and committed to close others). Our findings extend previous insights into patterns of cultural orientation beyond commonly examined East-West comparisons to an understudied world region. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Emoções , Comportamento Social , Humanos , Estados Unidos , Japão , Grupos Raciais , Reino Unido , Autoimagem
6.
Cogn Emot ; 37(3): 466-485, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36852838

RESUMO

Previous research has found a rich lexicon of shame and guilt terms in Chinese, but how comparable these terms are to "shame" or "guilt" in English remains a question. We identified eight commonly used Chinese terms translated as "shame" and "guilt". Study 1 assessed the Chinese terms' intensities, social characteristics, and action tendencies among 40 Chinese speakers. Testing term production in the reverse direction, Study 2 asked another Chinese-speaking sample (N = 85) to endorse emotion terms in response to eight eliciting scenarios generated using each term's social characteristics from Study 1. A native English-speaking sample (N = 83) was also included to examine the production of English emotion terms and compare motivational tendencies cross-culturally. Using this cross-referencing method, we found that some of the Chinese terms shared similar social-functional characteristics to their English translation, but some had distinct profiles. The two large shame-like and guilt-like term categories yielded in Study 1 were replicated in Study 2's Chinese term-production task where larger-scale correspondences between categorised elicitors and term clusters were found. Meanwhile, English speakers' term use provided further evidence for the equivalence between some Chinese terms and "shame" or "guilt" both in terms of their social and motivational characteristics.


Assuntos
Culpa , Idioma , Vergonha , Humanos , Emoções
7.
J Environ Sci (China) ; 127: 495-507, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522080

RESUMO

Copper (Cu) exists in a variety of forms in different aquatic environments, and affects their bioavailability. In this study we provide a systematic review on toxicity of Cu which focuses on identifying evidence in the mechanisms of Cu toxicity, and apply an adverse outcome pathway (AOP) analysis to identify multiple potential mechanisms and their interactions of Cu toxicity to fish. This analysis process included the mechanisms of behavior toxicant, oxidative toxicant, ion regulation disruption toxicity, as well as endocrine disruption toxicity. It was found that at low levels of Cu exposure, swimming, avoid predators, locating prey and other sensory functions will be impaired, and the organism will suffer from metabolic alkalosis and respiratory acidosis following the inhibition of the carbonic anhydrase active. The main pathway of acute toxicity of Cu to fish is the inhibition of the Na+/K+-ATPase enzyme, and lead to reduced intracellular sodium absorption, as well as Cu-induced increased cell permeability, in turn resulting in increased sodium ion loss, leading to cardiovascular collapse and respiratory insufficiency. The endocrine disruption toxicity of Cu to fish caused growth inhibition and reproductive reduction. In addition, there are several key pathways of Cu toxicity that are affected by hardness (e.g., Ca2+) and intracellular DOC concentrations, including inhibiting Cu-induction, improving branchial gas exchange, altering membrane transport functions, decreasing Na+ loss, and increasing Na+ uptake. The results of the AOP analysis will provide a robust framework for future directed research on the mechanisms of Cu toxicity.


Assuntos
Rotas de Resultados Adversos , Poluentes Químicos da Água , Animais , Cobre/toxicidade , Cobre/análise , Disponibilidade Biológica , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Sódio , Peixes/metabolismo , Íons
8.
Front Pharmacol ; 13: 965770, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339553

RESUMO

Objective: The aim of this research was to investigate the therapeutic efficacy of lenvatinib combined with sequential transarterial chemoembolization (TACE) on primary hepatocellular carcinoma (HCC) and the effects on serum basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). Method: A total of 104 patients with primary HCC, admitted to People's Hospital of Leshan from April 2018 to January 2021, were selected as the study subjects and were divided into the TACE-LEN group (n = 53) who were treated with lenvatinib combined with sequential TACE and the TACE group (n = 51) who were treated with TACE alone, according to the appropriate treatment modalities. The clinical efficacy 8 weeks after treatment; the serum levels of total bilirubin, conjugated bilirubin, and alanine aminotransferase (ALT); the prothrombin time (PT); the indocyanine green retention rate at 15 min (ICGR15); and the serum bFGF and VEGF levels before treatment and at 8 weeks after treatment were compared between the two groups. The incidence of adverse events and the survival rates at 18 months were also recorded for both groups. COX regression analysis was used to analyze the risk factors affecting the survival of patients. Results: Eight weeks after treatment, the objective response rate was higher in the TACE-LEN group than in the TACE group (77.36% vs. 56.36%, p < 0.05), but there were no statistically significant differences in the bilirubin and ALT levels, the PT, and the ICGR15 between the two groups (p > 0.05). The serum bFGF and VEGF levels post-therapeutic were lower in the TACE-LEN group than in the TACE group (p < 0.05). The differences in the incidence of postoperative adverse events and the survival rate within 6 months were not statistically significant between the two groups (p > 0.05). In addition, the survival rates within 12 and 18 months after treatment were higher in the TACE-LEN group than in the TACE group than in the TACE group (81.1% vs. 64.7%, 69.8% vs. 49.1%, p < 0.05). ICG-R15 and treatment regimen are risk factors for survival. Conclusion: The worse the liver reserve is, the worse the prognosis is. The combination of TACE and lenvatinib showed better efficacy and longer survival than TACE monotherapy for HCC patients and reduced the levels of bFGF and VEGF.

9.
Bull Environ Contam Toxicol ; 108(6): 995-1000, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35322278

RESUMO

Water quality criteria (WQC) play an important role in the environmental management of pollutants in different countries or institutions. It has been found that endocrine disrupting chemicals (EDCs) can potentially alter functions of the endocrine system and consequently cause adverse effects in aquatic organisms. Therefore, the complicated modes of action and mechanisms of EDCs should be carefully considered in WQC studies. For example, the research regarding the WQC derivation of EDCs should prioritize sensitive aquatic species in consideration of the WQC derivation. Second, the chronic toxicity of EDCs should be of utmost concern. In addition, the appropriate effects and endpoints of EDCs should be carefully selected for the WQC derivation. Moreover, it was pointed out that some new methods should be taken into consideration in the WQC studies of EDCs in the near future.


Assuntos
Disruptores Endócrinos , Poluentes Ambientais , Poluentes Químicos da Água , Disruptores Endócrinos/toxicidade , Sistema Endócrino , Poluentes Ambientais/toxicidade , Poluentes Químicos da Água/toxicidade , Qualidade da Água
10.
IEEE Trans Pattern Anal Mach Intell ; 44(2): 710-722, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-30969916

RESUMO

With the maturity of visual detection techniques, we are more ambitious in describing visual content with open-vocabulary, fine-grained and free-form language, i.e., the task of image captioning. In particular, we are interested in generating longer, richer and more fine-grained sentences and paragraphs as image descriptions. Image captioning can be translated to the task of sequential language prediction given visual content, where the output sequence forms natural language description with plausible grammar. However, existing image captioning methods focus only on language policy while not visual policy, and thus fail to capture visual context that are crucial for compositional reasoning such as object relationships (e.g., "man riding horse") and visual comparisons (e.g., "small(er) cat"). This issue is especially severe when generating longer sequences such as a paragraph. To fill the gap, we propose a Context-Aware Visual Policy network (CAVP) for fine-grained image-to-language generation: image sentence captioning and image paragraph captioning. During captioning, CAVP explicitly considers the previous visual attentions as context, and decides whether the context is used for the current word/sentence generation given the current visual attention. Compared against traditional visual attention mechanism that only fixes a single visual region at each step, CAVP can attend to complex visual compositions over time. The whole image captioning model-CAVP and its subsequent language policy network-can be efficiently optimized end-to-end by using an actor-critic policy gradient method. We have demonstrated the effectiveness of CAVP by state-of-the-art performances on MS-COCO and Stanford captioning datasets, using various metrics and sensible visualizations of qualitative visual context.


Assuntos
Algoritmos , Políticas , Animais , Cavalos , Humanos
11.
IEEE Trans Pattern Anal Mach Intell ; 44(2): 684-696, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-30990419

RESUMO

Grounding natural language in images, such as localizing "the black dog on the left of the tree", is one of the core problems in artificial intelligence, as it needs to comprehend the fine-grained language compositions. However, existing solutions merely rely on the association between the holistic language features and visual features, while neglect the nature of composite reasoning implied in the language. In this paper, we propose a natural language grounding model that can automatically compose a binary tree structure for parsing the language and then perform visual reasoning along the tree in a bottom-up fashion. We call our model RvG-Tree: Recursive Grounding Tree, which is inspired by the intuition that any language expression can be recursively decomposed into two constituent parts, and the grounding confidence score can be recursively accumulated by calculating their grounding scores returned by the two sub-trees.RvG-Tree can be trained end-to-end by using the Straight-Through Gumbel-Softmax estimator that allows the gradients from the continuous score functions passing through the discrete tree construction. Experiments on several benchmarks show that our model achieves the state-of-the-art performance with more explainable reasoning.


Assuntos
Inteligência Artificial , Idioma , Algoritmos , Humanos , Aprendizagem
12.
Environ Pollut ; 274: 116586, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33529897

RESUMO

Cresyl diphenyl phosphate (CDP), as a kind of aryl substituted organophosphate esters (OPEs), is commonly used as emerging flame retardants and plasticizers detected in environmental media. Due to the accumulation of CDP in organisms, it is very important to discover the toxicological mechanism and metabolic process of CDP. Hence, liver microsomes of crucian carps (Carassius carassius) were prepared for in vitro metabolism kinetics assay to estimate metabolism rates of CDP. After 140 min incubation, the depletion of CDP accounted for 58.1%-77.1% (expect 0.5 and 2 µM) of the administrated concentrations. The depletion rates were best fitted to the Michaelis-Menten model (R2 = 0.995), where maximum velocity (Vmax) and Michaelis-Menten constant (Km) were 12,700 ± 2120 pmol min-1·mg-1 protein and 1030 ± 212 µM, respectively. Moreover, the in vitro hepatic clearance (CLint) of CDP was 12.3 µL min-1·mg-1 protein. Log Kow and bioconcentration factor (BCF) of aryl-OPEs were both higher than those of alkyl- and chlorinated-OPEs, indicating that CDP may easily accumulate in aquatic organisms. The results made clear that the metabolism rate of CDP was greater than those of other OPEs detected in liver microsomes in previous research. This paper was first of its kind to comprehensively investigate the in vitro metabolic kinetics of CDP in fish liver microsomes. The present study might provide useful information to understand the environmental fate and metabolic processes of these kinds of substances, and also provide a theoretical basis for the ecological risk assessment of emerging contaminants.


Assuntos
Carpas , Retardadores de Chama , Animais , Compostos de Bifenilo , Cinética , Microssomos Hepáticos , Organofosfatos , Fosfatos
13.
Chemosphere ; 262: 127768, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32777611

RESUMO

Heavy metals and antimicrobial resistant bacteria in livestock and poultry environments can cause declines in production and significant economic losses, leading to potential environmental and public health issues. In this study, the heavy metal pollution status of livestock breeding water bodies in the Dawen river basin of Shandong Province in China was evaluated, and a total of 10 heavy metals were measured. In addition, antimicrobial susceptibility tests were conducted for Escherichia coli strains isolated from the water samples. The results showed that among all the metals, copper, zinc, and iron were detected at each sampling point, followed by nickel (detection rate of 95.74%), arsenic (detection rate of 89.36%), selenium (detection rate of 68.09%), lead (detection rate of 27.66%), and mercury (detection rate of 12.77%). Cadmium and hexavalent chromium were not detected. The contents of nine heavy metals were below the existing water standard values in China, whereas the iron pollution index in the water body in the study area was large and may pose a potential risk. A total of 17 E. coli isolates showed different resistance to ß-lactams, aminoglycosides, tetracyclines, quinolone antibiotics and chloramphenicol, but were mainly resistant to ß-lactams and tetracyclines. The detection rate of the tetA resistance gene was relatively high, indicating the overuse of cephalosporins and tetracyclines. The results of the present study might provide evidence of metal pollution and theoretical basis on the treatment of colibacillosis in the livestock industries.


Assuntos
Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Monitoramento Ambiental/métodos , Escherichia coli/isolamento & purificação , Metais Pesados/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Antibacterianos/farmacologia , China , Indústria de Laticínios , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Fazendas , Rios/química , Rios/microbiologia , Águas Residuárias/microbiologia
14.
Chemosphere ; 266: 128989, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33228983

RESUMO

Following the world-wide ban of brominated flame retardants (BFRs), organophosphate esters (OPEs), which could potentially affect human health and ecosystem safety, have been frequently detected in various environmental media. However, the knowledge regarding the underlying toxicity effects of OPEs remains limited. In order to address these issues, this study reviewed the related reports which have been published in recent years. This analysis process included 12 OPEs, 10 model organisms, and 15 cell lines, which were used to systematically examine the mechanisms of endocrine disruption, neurotoxicity, hepatotoxicity, and cardiotoxicity, as well as reproductive and developmental toxicity. Subsequently, an adverse outcome pathway (AOP) framework of the toxicological effects of OPEs was built. The results demonstrated that multiple different pathways may lead to a single same adverse outcome (AO), and there was a certain degree of correlation among the different AOs. It was found that among all the 12 OPEs, tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) may potentially be the most toxic. In addition, rather than the parent chemicals, the metabolites of OPEs may also have different degrees of toxicity effects on aquatic organisms and humans. Overall, the results of the present study also suggested that an AOP framework should be built via fully utilizing the existing toxicity data of OPEs based on in vivo-in vitro-in silico to completely and deeply understand the toxic mechanisms of OPEs. This improved knowledge could then provide a theoretical basis for ecological risk assessments and water quality criteria research in the near future.


Assuntos
Rotas de Resultados Adversos , Retardadores de Chama , China , Ecossistema , Monitoramento Ambiental , Ésteres/toxicidade , Retardadores de Chama/análise , Retardadores de Chama/toxicidade , Humanos , Organofosfatos/toxicidade
15.
Environ Pollut ; 264: 114788, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32559856

RESUMO

Tris (1,3-dichloro-2-propyl) phosphate (TDCPP) is a type halogenated organophosphate flame retardants (OPFRs), which has been identified as contaminants of emerging concern (CECs). The use and production of OPFRs began to increase gradually when brominated flame retardants (BFRs) were banned. Halogenated OPFRs, especially TDCPP have been considered to lead to mutagenicity and carcinogenesis and major concerns have been raised regarding their toxicity. In this study, the toxicity effects and mechanisms of TDCPP were summarized and ecological risk assessment was made regarding its potential impact on freshwater organisms. TDCPP has been widely detected in ecosystems throughout the world, with observed toxicity effects on both humans and freshwater organisms. Inhalation of the dust was found to be the main exposure for humans. TDCPP could be metabolized in the human body, and medium stability was achieved in human body with the main metabolite BDCPP. Aside from mutagenicity and carcinogenesis, TDCPP was also found to have the potential for endocrine disruption and impairing the human reproductive system. Furthermore, this study reviewed the results of previous toxicity experiments, including acute toxicity, growth and development toxicity, neurotoxicity, and hepatotoxicity in freshwater organisms. Risk assessment was made using the safety threshold method by comparing the toxicity data with the exposure data in freshwater. HC5 (hazardous concentration for 5% of organisms) derived based on traditional endpoints of acute toxicity LC50 (median lethal concentration) or EC50 (concentration for 50% of maximal effect) was 877 µg/L. This value was much higher than the exposure concentration levels in the surface water with EXD90 (exposure data with cumulative probability 90%) of 65.22 ng/L. However, based on the growth and development toxicity data, the derived HC5 was 33.33 ng/L and the calculated MOS (margin of safety) was below 1. Therefore, the results validated the fact that the ecological risk of TDCPP could not be neglected for its growth and development toxicity.


Assuntos
Retardadores de Chama , Fosfatos , Ecossistema , Água Doce , Humanos , Organofosfatos , Compostos Organofosforados , Medição de Risco
16.
Molecules ; 25(3)2020 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-31991928

RESUMO

A highly efficient sulfonylation of para-quinone methides with sulfonyl hydrazines in water has been developed on the basis of the mode involving a tetrabutyl ammonium bromide (TBAB)-promoted sulfa-1,6-conjugated addition pathway. This reaction provides a green and sustainable method to synthesize various unsymmetrical diarylmethyl sulfones, showing good functional group tolerance, scalability, and regioselectivity. Further transformation of the resulting diarylmethyl sulfones provides an efficient route to some functionalized molecules.


Assuntos
Indolquinonas/química , Compostos de Amônio Quaternário/química , Sulfonas/química , Água/química , Catálise , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Solventes , Temperatura
17.
Bull Environ Contam Toxicol ; 103(6): 789-795, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31605158

RESUMO

Copper (Cu) bioavailability varies under water conditions. In the present study, the whole life of zebrafish was divided into three different life stages (larvae, juvenile and adult) based on the growth curve, then the influences of water hardness and dissolved organic carbon (DOC) concentration on the acute toxicity of zebrafish were respectively investigated. The results indicated that the life stages had significant effects on Cu toxicity. The larvae stage was less sensitive to Cu than both the juvenile and adult stages. With the increase of water hardness, the toxicity of Cu on zebrafish was decreased, a linear relationship was observed between water hardness and Cu toxicity, and the same was true for DOC concentration. The results showed that taking the 24 days juvenile zebrafish to study the water quality criteria of Cu was stable, sensitive and economical.


Assuntos
Cobre/toxicidade , Água Doce/química , Hidrocarbonetos/toxicidade , Larva/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Cobre/química , Dureza , Hidrocarbonetos/química , Solubilidade , Testes de Toxicidade Aguda , Poluentes Químicos da Água/química , Qualidade da Água/normas
18.
Int J Biol Macromol ; 141: 1035-1043, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31520702

RESUMO

In this work, natural polysaccharide product sodium alginate (SA) served as templates to prepare porous calcium silicate (CS) hydroxyapatite (HA) composite microspheres (CHCM) with high specific surface area by a new route combining ion exchange and calcination. CHCM played an important role in the fields of environmental protection with its large specific surface area, excellent adsorptive property, high mechanical strength and good regeneration performance. In order to explore its treatment capacity of wastewater, a series of eriochromeblue black R (EBBR) adsorption experiments were carried out. The equilibrium data fitted well with the Langmuir isotherm with a maximum adsorption capacity of 76.80 mg/g. Electrostatic interaction, ionic bonds and physical adsorption were responsible for the interactions between the EBBR and CHCM. Meanwhile, the CHCM maintained complete spherical and almost undamaged in the regeneration experiments, which confirmed its stability for cyclical usage. This paper demonstrates the role of natural polysaccharide product sodium alginate serving as templates to prepare useful products with potential wide applications.


Assuntos
Alginatos/química , Compostos de Cálcio/química , Corantes/química , Corantes/isolamento & purificação , Durapatita/química , Silicatos/química , Purificação da Água/métodos , Água/química , Adsorção , Cinética , Termodinâmica , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
19.
J Phys Condens Matter ; 29(42): 425601, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28737502

RESUMO

Based on a self-consistent method, we predict theoretically that there exist intrinsic plasmarons in graphene at nonzero temperature, with a well defined mode, as shown by the result of Landau damping. We find that there are sharp differences between the discussed system and the QCD/QED system. Firstly, the thermal mass is proportional to [Formula: see text] but not [Formula: see text]. Secondly, at [Formula: see text], the fermion channel and plasmaron channel are nearly degenerate, and furthermore the energy difference between fermion and plasmaron becomes larger and larger with increasing q in the region [Formula: see text]. Thirdly, the fermion behaves as a 'relativistic particle' with nonzero mass, and the plasmaron exhibits an abnormal dispersion at moderate momentum.

20.
J Diabetes Investig ; 8(4): 554-559, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27863107

RESUMO

AIMS/INTRODUCTION: To evaluate the glycometabolism and outcomes of gestational diabetes mellitus (GDM) patients according to the International Association of Diabetes and Pregnancy Study Group (IADPSG) criteria in China. MATERIALS AND METHODS: According to the results of a 75-g oral glucose tolerance test, 1,683 pregnant women were divided into three groups: (i) an increment GDM group (patients meet the IADPSG criteria, but not the previous Chinese criteria); (ii) a stock GDM group (patients meet both criteria); and (iii) a normal glucose tolerance group. Their glycometabolism outcomes, prepregnancy and postpartum body mass index were compared, as were maternal-fetal outcomes. RESULTS: The IADPSG and previous Chinese criteria diagnosed 12.4% and 5.5% of women with GDM. Pairwise comparison showed significant differences in 1-h plasma glucose, 2-h plasma glucose, HbA1c values and area under curve of glucose among all groups (P < 0.01). The fasting plasma glucose and postpartum body mass index of the stock group were significantly higher than those of the other two groups (P < 0.01). The incidences of hypertensive disorder complicating pregnancy and cesarean section of the normal glucose tolerance group were significantly lower than those of the other two groups (P < 0.001). No significant differences in patient age, prepregnancy body mass index, duration of pregnancy, prevalence of premature labor, premature rupture of membranes, neonatal jaundice, neonatal asphyxia or Ponderal Index were observed, but significant differences in macrosomia and neonatal hypoglycemia were observed (P < 0.05). CONCLUSIONS: The IADPSG criteria doubled the number of GDM patients. The cases of the increment patients were mild. The IADPSG criteria should be discussed fully before implementation in China.


Assuntos
Metabolismo dos Carboidratos , Diabetes Gestacional/metabolismo , Adulto , Feminino , Glucose/metabolismo , Humanos , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Adulto Jovem
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