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1.
BMC Psychiatry ; 21(1): 427, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465307

RESUMO

BACKGROUND: This study aimed to describe the prevalence and lifetime criteria profiles of DSM-5 alcohol use disorder (AUD) and the transitions from alcohol use to disorder in Chifeng, China. METHODS: Face-to-face interviews were conducted using Composite International Diagnostic Interview-3.0 (CIDI-3.0) among 4528 respondents in Chifeng. RESULTS: The weighted lifetime and 12-month prevalence of DSM-5 AUD were 3.03 and 1.05%, respectively. Mild lifetime AUD was the most prevalent severity level (69.53%). The two most common criteria were "failure to quit/cutdown" and "drinking more or for longer than intended." Lifetime prevalence was 65.59% for alcohol use, and 22.97% for regular drinking. Male and domestic violence were risk factors for the transition from alcohol use to regular drinking or AUD and from regular drinking to AUD. Younger age was risk factor for the transition to AUD from alcohol use or regular drinking. Poverty (OR = 2.49) was risk factor for the transition from alcohol use to regular drinking. The earlier drinkers were more likely to develop to regular drinking (OR = 2.11). CONCLUSION: AUD prevalence in Chifeng was not as high as that in Western countries. The study revealed that multiple risk factors might contribute to the transition across different stages of alcohol use. Further research should explore the underlying mechanisms.


Assuntos
Transtornos Relacionados ao Uso de Álcool , Alcoolismo , Consumo de Bebidas Alcoólicas/epidemiologia , Transtornos Relacionados ao Uso de Álcool/diagnóstico , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Alcoolismo/diagnóstico , Alcoolismo/epidemiologia , China/epidemiologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Masculino , Prevalência , Fatores de Risco
2.
Carbohydr Polym ; 267: 118233, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119185

RESUMO

Cellulose nanofibers (CNFs) aerogel was prepared via simple covalent crosslinking and freeze-drying method. The porous cellulose aerogel possessed high specific surface area and high metal-chelating capacity, which showed fast adsorption kinetics and high adsorption capacity (440.60 mg g-1) in static uranium adsorption process. In the dynamic filtration system, the maximum adsorption capacity reached 194 mg g-1 with the initial concentration of 10 mg L-1. In addition, the CNFs aerogel possessed excellent selectivity and good regeneration ability for uranium adsorption. The integrated analyses of attenuated total reflection Fourier transform infrared (ATR-FTIR), X-Ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS) suggested that the predominant UO22+ species formed inner-sphere surface complexes with two active carboxyl groups in the coordination model. This strategy may provide a sustainable route for development of efficient biomass-based adsorbents for selective uranium removal from aqueous solution.

3.
Inflammation ; 44(4): 1370-1380, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33630211

RESUMO

L-arginine (Arg), a semi-essential amino acid, has recently been shown to attenuate inflammatory response during cardiovascular disease. NLRP3 inflammasome serves a central role in amplification of cellular inflammation. In this study, we aimed to confirm the modulatory effect of Arg on NLRP3 inflammasome and the underlying mechanisms in vascular endothelial cells (ECs). Arg suppressed NLRP3 inflammasome activation in ECs stimulated with lipopolysaccharide (LPS) and adenosine triphosphate (ATP). Moreover, treatment with Arg increased the expression of the deacetylase sirtuin 1 (SIRT1) in ECs. Importantly, knockdown of SIRT1 abolished the inhibitory potential of Arg on the activation of NLRP3 inflammasome. Further study indicated that Arg also alleviated LPS plus ATP-induced the generation of reactive oxygen species (ROS) in ECs. In addition, Arg may regulate NLRP3 inflammasome activation partly through suppression of ROS production. In combination, we speculate that Arg exerts an inhibitory effect on the activation of NLRP3 inflammasome in ECs, which may be partly mediated by SIRT1 and ROS.

4.
Surgery ; 169(6): 1333-1339, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33461779

RESUMO

BACKGROUND: This meta-analysis was performed to evaluate the effect of Seprafilm® on postoperative small bowel obstruction. METHODS: A literature search was conducted in the PubMed and EMBASE databases through August 2020. The pooled risk ratios as well as the corresponding 95% confidence intervals were calculated using RevMan 5.3 software. RESULTS: A total of 9 clinical control trials involving 4,351 patients (2,123 in the Seprafilm® group and 2,228 in the control group) were included. The overall analysis showed that the pooled risk ratio was 0.45 (95% confidence interval = 0.34-0.60; P < .00001), indicating that the risk of postoperative small bowel obstruction can be significantly decreased by the application of Seprafilm®. Similarly, an obvious effect of Seprafilm® on reducing the rate of postoperative small bowel obstruction was also shown in the subgroup analyses by population (adult participants), study design (randomized control study or nonrandomized control study), region (Japan or Korea), follow-up duration (2 years or 5 years), and sheet number of Seprafilm® (1 sheet or >1 sheet). CONCLUSION: In conclusion, the use of Seprafilm® is beneficial for decreasing the rate of postoperative small bowel obstruction.


Assuntos
Carboximetilcelulose Sódica/administração & dosagem , Ácido Hialurônico/administração & dosagem , Obstrução Intestinal/prevenção & controle , Intestino Delgado , Membranas Artificiais , Complicações Pós-Operatórias/prevenção & controle , Abdome/cirurgia , Humanos , Fatores de Risco
5.
Angew Chem Int Ed Engl ; 60(13): 7174-7179, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33415810

RESUMO

Self-sorting plays a crucial role in living systems such as the selective assembly of DNA and specific folding of proteins. However, the self-sorting of artificial helical polymers such as biomacromolecules has rarely been achieved. In this work, single-handed helical poly(phenyl isocyanide)s bearing pyrene (Py) and naphthalene (Np) probes were prepared, which exhibited interesting self-sorting properties driven by both helicity and molecular weight (Mn ) in solution, solid state, gel, and on the gel surface as well. The polymers with the same helix sense and similar Mn can self-sort and assemble into well-defined two-dimensional smectic architectures and form stable gels in organic solvents. In contrast, mixed polymers with opposite handedness or different Mn were repulsive to each other and did not aggregate. Moreover, the gels of helical polymers with the same handedness and similar Mn can recognize themselves and adhere together to form a gel.

6.
Inorg Chem ; 59(16): 11298-11304, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32799460

RESUMO

It is urgent to find a catalyst with high selectivity and efficiency for the reduction of CO2 by renewable electric energy, which is the important means to reduce the greenhouse effect. In this work, we report that the metal-organic framework (MOF) indium-based 1,4-benzenedicarboxylate (In-BDC) catalyzes CO2 to formate with a Faradaic efficiency (FEHCOO-) of more than 80% in a wide voltage range between -0.419 and -0.769 V (vs. reversible hydrogen electrode, RHE). In-BDC performs at a maximum FEHCOO- of 88% at -0.669 V (vs. RHE) and a turnover frequency of up to 4798 h-1 at -1.069 V (vs. RHE). The long-term durability of 21 h and reusability of the electrocatalyst are clearly demonstrated. It opens up a new opportunity to utilize MOF with novel metal motifs for the efficient electroreduction of CO2.

7.
J BUON ; 25(3): 1504-1511, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32862597

RESUMO

PURPOSE: In the present investigation the hydrophilic drug doxorubicin (DOX) was successfully incorporated with the drug carrier GE11 which serves as marker for tumor cells in non small cell lung cancer(NSCLC) to form the liposomal formulation. METHODS: The formulation was fabricated in two steps: one being the preparation of liposomal formulation using reverse phase evaporation method and second is synthesis of DSPE-PEG 2000 - GE 11complex. RESULTS: Thus prepared liposomes when evaluated via scanning electron spectroscopy showed smooth and spherical surface with particle size ranging between 102±0.3 to 120±0.5 nm. The percent encapsulation efficiency was 65.34 with highest drug release of 98% up to 45 h. The cytotoxic study revealed the non-toxic nature of carrier protein (i.e. GE11). The microbiological study has shown the antibiotic efficiency of liposomal formulation to be comparable with pure drug. In vivo cellular uptake study showed efficiency of GE11 protein in accumulation in tumor cells. The study conducted in mice showed more reduction in tumor size with liposomal formulation (312 mm3) than with pure drug (540 mm3). CONCLUSION: DOX loaded liposomes with GE11 as carriers were successfully formulated by using reverse phase evaporation method. The prepared liposomal formulation was found to be most effective in combating cancer cells when compared to pure drug.


Assuntos
Doxorrubicina/análogos & derivados , Doxorrubicina/farmacologia , Lipossomos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Lipossomos/química , Camundongos , Camundongos Nus , Tamanho da Partícula , Peptídeos/química , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
8.
Carbohydr Polym ; 245: 116627, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32718662

RESUMO

Uranium extraction from seawater is considered as an efficient strategy to meet the increasing demands of uranium. Amidoxime has been reported as one of the most efficient groups for uranium affinity. Herein, amidoximated cellulose fibers were synthesized by grafting polyacrylonitrile (PAN) onto cellulose fibers followed by amidoxime modification. The amidoximated cellulose fibers showed maximum adsorption capacity of 52.88 mg g-1 (pH = 5.0), and its static adsorption process was well fitted with Langmuir model and Pseudo-second-order kinetics. The adsorption mechanism was attributed to the chelating reaction between uranyl complexes and amidoximated cellulose fibers. The prepared fibers were further fabricated into nonwoven membrane for dynamic adsorption, and the breakthrough curves were well fitted to Dose-Response model. The amidoximated cellulose fiber membrane showed a good adsorption capacity of 1.22 mg g-1 at pH 8.0 after filtrating 10.0 L simulated seawater, demonstrating promising efficient engineering materials for uranium extraction from seawater.


Assuntos
Celulose/química , Membranas Artificiais , Oximas/química , Água do Mar/química , Urânio/química , Resinas Acrílicas/química , Adsorção , Celulose/síntese química , Filtração/métodos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Cinética , Espectroscopia Fotoeletrônica , Polimerização , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Angew Chem Int Ed Engl ; 59(38): 16675-16682, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32543000

RESUMO

Controlling the self-assembly morphology of π-conjugated block copolymer is of great interesting. Herein, amphiphilic poly(3-hexylthiophene)-block-poly(phenyl isocyanide)s (P3HT-b-PPI) copolymers composed of π-conjugated P3HT and optically active helical PPI segments were readily prepared. Taking advantage of the crystallizable nature of P3HT and the chirality of the helical PPI segment, crystallization-driven asymmetric self-assembly (CDASA) of the block copolymers lead to the formation of single-handed helical nanofibers with controlled length, narrow dispersity, and well-defined helicity. During the self-assembly process, the chirality of helical PPI was transferred to the supramolecular assemblies, giving the helical assemblies large optical activity. The single-handed helical assemblies of the block copolymers exhibited interesting white-light emission and circularly polarized luminescence (CPL). The handedness and dissymmetric factor of the induced CPL can be finely tuned through the variation on the helicity and length of the helical nanofibers.

10.
Onco Targets Ther ; 13: 2807-2817, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32308415

RESUMO

Background: Irinotecan (IRI) is considered an option for second-line treatment of advanced gastric cancer; however, acquired drug resistance currently limits its clinical application. Recently, many researchers have shown that autophagy plays a crucial role in the resistance of tumor cells to chemotherapy and radiotherapy. In this study, we investigated the relationship between autophagy and antitumor activity of IRI in gastric cancer cells. Methods: We used MTT assay, flow cytometry and immunofluorescence staining to detect viability, apoptosis and autophagy in gastric cancer. Western blotting assay was used to determine the expression of LC3, Beclin-1, P62, cleaved PARP and Caspase 3. In vivo animal study was performed finally. Results: We found that IRI treatment dose- and time-dependently inhibited growth and induced apoptosis in gastric cancer cells. Moreover, IRI treatment caused autophagy in these cells, whereas autophagy inhibitors-3-methyladenine (3-MA), chloroquine (CQ), and Beclin-1 small interfering RNA (siRNA)-suppressed cytotoxicity of IRI. A mechanistic analysis showed that IRI-induced autophagy and apoptosis were related to increased reactive oxygen species (ROS) accumulation and activation of the JNK- and p38-MAPK pathways. Further in vivo experiments revealed that IRI suppressed tumor growth, induced autophagy, and stimulated the JNK- and p38-MAPK pathways, whereas 3-MA attenuated these effects. Conclusion: Taken together, these results indicate that IRI stimulates the ROS-related JNK- and p38-MAPK pathways to promote autophagy-dependent apoptosis. Thus, a combination of IRI with a pharmacological autophagy enhancer may be a promising therapeutic strategy against gastric cancer.

11.
Water Sci Technol ; 81(1): 52-61, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32293588

RESUMO

A fiber-network chitosan film with three-dimensional interconnected structure was prepared in an alkali/urea solution and regenerated from an ethanol/water coagulation solution. The surface morphology and structure were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), N2 adsorption-desorption, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). Batch adsorption for uranium U(VI) was conducted to investigate the effects of pH, contact time and initial uranium concentration on adsorption capacity. The adsorption of CS-80% was in good agreement with the pseudo-second-order kinetic model and Langmuir isotherm model. The three-dimensional interconnected structure provided more active sites and favored the diffusion of uranium solute, and therefore enhanced the adsorption capacity. The maximum adsorption capacity at pH 5 was 196.735 mg/g. The adsorption mechanism was attributed to chelation and coordination of uranium with -NH2 and -OH groups on chitosan molecules.


Assuntos
Quitosana , Urânio , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
12.
Int J Biol Macromol ; 157: 10-16, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32335109

RESUMO

Pasting and rheological properties of starch from soft rice and two traditional rice varieties were analyzed. Soft rice starch was found to have a low pasting temperature of 67.2 °C, with a high system viscosity, including peak and trough viscosity. The storage modulus and loss modulus of soft rice starch were high and showed good viscoelasticity. The amylose content of soft rice starch was found to be 11.3%, classifying it was low amylose content type. Compared with japonica rice starch, soft rice starch had lower solubility but higher swelling power, gel consistency, and water binding capacity. The medium particle size and volume mean particle size of soft rice starch were the highest. The average molecular weight of soft rice starch was 5.4 × 107. The molecular density and proportion of short amylopectin side chains, with a range of 6-12, were the highest among all varieties tested. These findings provide a theoretical basis for the processing of soft rice starch and breeding of high-quality rice.


Assuntos
Oryza/química , Amido/química , Amilopectina/análise , Amilose/análise , Elasticidade , Solubilidade , Viscosidade , Água/química
13.
Carbohydr Polym ; 233: 115838, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32059891

RESUMO

In this study, TiO2 nanocrystals were synthesized in the scaffold of cellulose nanocrystal (CNC) using in situ hydrolysis, where the morphology and size of TiO2 was controlled by CNC's functional groups and surface charge. The resulting TiO2/CNC nanocomposites showed a superior photocatalytic activity for Cr(VI) reduction under visible light (λ > 420 nm) due to the combined effects of small TiO2 size and ligand-to-metal charge transfer (LMCT) complex between CNC and TiO2. It was found that the charge-enriched CNC not only acted as a template to direct the crystal growth of TiO2, but also played essential roles on light harvesting and charge transfer thereby promoting the photoreduction of Cr(VI). The demonstrated system represents a unique pathway to develop a lower cost and efficient purification material for remediation of Cr(VI).

14.
J Hazard Mater ; 391: 122020, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32058226

RESUMO

Short activated carbon fibers (ACF) with high surface area were fabricated via carbonization in N2 and activation in CO2 at high temperatures, with cellulose fibers as the raw materials. The obtained ACF were subsequently deposited into the support layer of a polyethersulfone (PES) ultrafiltration membrane by a facile filtration process to obtain the sandwich structured ACF-PES composite membrane. The hormone (17ß-estradiol, E2) adsorption kinetics and isotherm of ACF in static conditions, as well as E2 removal by filtration with the ACF-PES composite membrane were investigated. In static conditions, ACF rapidly and efficiently adsorbs E2 evidenced by a high removal of >97 %. The fitting of second order kinetics and linear (Henry) adsorption isotherm models indicated the availability of easily accessible adsorption sites. Besides, such efficient E2 adsorption was contributed by many interactions between E2 and ACF, namely hydrophobic interactions, hydrogen bonding and π-π stacking. The incorporation of ACF in a PES membrane resulted in a minor loss of filtration flux compared with the control membrane, but significantly improved E2 removal through adsorption pathway. With only 1.0 mg ACF incorporated (loading 2.0 g/m2), the composite membrane could reject 76 % of E2 from a 100 ng/L solution at a flux of 450 L/m2∙h, demonstrating that ACF-PES can overcome the permeability-selectivity trade-off of traditional UF membranes.

15.
Water Res ; 168: 115182, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634706

RESUMO

Low-molecular-weight organic acids (LMWOAs) are ubiquitous in the aquatic environment and consequently may affect the heavy metal transport in aquifer systems. In this study, the influences of LMWOAs on the transport of Cd2+ under different pH conditions in saturated porous media were evaluated. For this, three LMWOAs such as acetic acid, tartaric acid, and citric acid were employed. A two-site nonequilibrium transport model was applied to simulate the transport data. Under acidic conditions (pH 5.0), the results indicated that LMWOAs inhibited the transport of Cd2+ even at the low concentrations of organic acids (i.e., 0.05 and 0.1 mM). The inhibition effects might be attributed to the complexation role of the sand surface-bound organic acids and also electrostatic interaction. Meanwhile, the inhibition effects of LMWOAs on Cd2+ transport in the following order of citric acid > tartaric acid > acetic acid, which was also in agreement with the decreasing complex stability constants between Cd2+ and LMWOAs. This order may be dependent on their molecular structures (i.e., amount and type of functional groups) and complexing strength. Interestingly, when the LMWOA concentrations 0.5 mM, tartaric acid and citric acid still inhibited Cd2+ transport, while acetic acid slightly enhanced the Cd2+ mobility due to its weaker complexing strength. However, under neutral conditions (pH 7.0), LMWOAs generally enhanced the transport of Cd2+. The transport-enhancement of LMWOAs was ascribed to the formation of stable aqueous non-adsorbing Cd-organic acid complexes. In addition, citric acid could obviously inhibit the transport of Cd2+ under competitive transport conditions (i.e., with competing cations), which is mainly due to different complex affinities of citric acid to Pb2+ and Cd2+. These findings demonstrate that LMWOAs may inhibit or facilitate Cd2+ transport under different environmental conditions. Thus, environmental assessment concerning the transport of heavy metals should consider the roles of organic acids.


Assuntos
Poluentes do Solo , Cádmio , Peso Molecular , Porosidade , Solo
16.
Integr Zool ; 15(3): 202-212, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31773863

RESUMO

The blue sheep is an endemic species to the Qinghai-Tibet Plateau and surrounding regions. It has been regarded as having 2 subspecies: Pseudois nayaur nayaur and P. n. szechuanensis. However, such a classification remains controversial. Herein, we analyze 10 microsatellite loci and part of the mitochondrial control region for clarification in such taxonomic debates. We use samples from 168 individuals from 6 geographic populations covering almost all the distribution areas of the species in China to carry out comparisons. Phylogenetic trees derived from both the microsatellite and mitochondrial markers combined with the discriminant analysis of principal components (DAPC) and the STRUCTURE analysis reveal that the individuals in the Helan Mountains are well grouped with a distinct evolutionary lineage and are significantly different from the other populations of P. n. szechuanensis according to Fst values, implying that this isolated population should be categorized as a valid subspecies; namely, Pseudois nayaur alashanicus. The isolation-by-distance (IBD) analysis shows a significant positive relationship between genetic and geographical distances among the populations.


Assuntos
Repetições de Microssatélites , Ruminantes/classificação , Animais , China , Variação Genética , Mitocôndrias/genética , Filogenia , Ruminantes/genética , Análise de Sequência de DNA/veterinária , Ovinos/classificação , Ovinos/genética
17.
Pak J Pharm Sci ; 32(5): 2139-2147, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31813880

RESUMO

Different polymorphic forms can affect the performance of the drug product. In addition, isomorphic crystals show different chemical and physical properties due to the changes in the crystal habit. However, it is unclear whether the crystal habit results in different pharmacological activity. The aim of this study was to investigate whether the pharmacological effect of ibuprofen could be affected due to the variety of the crystal habit. Solvent change technique and conventional fusion method were carried out to modify the characteristics of ibuprofen. The physicochemical properties of each were investigated using powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC) techniques. Results of scanning electron microscopy (SEM) analysis revealed differences in the surface characteristics of the crystals obtained. Further study revealed that the samples crystallized exhibited the remarkable variation on the dissolution profiles in different dissolution medium. Moreover, in vivo antinociceptive and anti-inflammatory findings demonstrated that the crystal habit modifications resulted in the different therapeutic efficacy. Taken together, these results indicate that the modification of the crystal habit had a great influence on the in vivo pharmacological activity of ibuprofen crystals.


Assuntos
Ibuprofeno/química , Ibuprofeno/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Varredura Diferencial de Calorimetria/métodos , Química Farmacêutica/métodos , Cristalização/métodos , Camundongos , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Pós/química , Pós/farmacologia , Ratos , Ratos Wistar , Solubilidade/efeitos dos fármacos , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X/métodos
18.
Environ Sci Process Impacts ; 21(7): 1153-1163, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31157350

RESUMO

Tetracycline is one of the most commonly used antibiotics in the world. Eventually, large amounts of this contaminant will enter into the subsurface environment, where a variety of ions exist. In this study, the effects of divalent metal cations (Mg2+, Ca2+, Pb2+ and Cu2+) and inorganic anions (Cl-, NO3-, SO42- and H2PO4-) on the transport of tetracycline in saturated porous media were investigated. Both batch and column experiments were conducted to determine the interactions between tetracycline and sand. Batch sorption experimental results showed that the presence of divalent metal cations could increase the sorption of tetracycline onto sand due to the cation-bridging mechanism. When Na+ was the counterion in the background solution, anions caused a significant decrease in tetracycline sorption owing to the occupation of some adsorption sites by anions and the decrease of electrostatic attraction. Column experiments indicated that the inhibition effects of divalent cations followed the order of Cu2+ > Pb2+ > Ca2+ ≈ Mg2+; the regular pattern might be related to their different complexing strengths. The presence of inorganic anions enhanced the mobility of tetracycline following the order of H2PO4- > SO42- > NO3- > Cl-. Transport-enhancement effects of anions were ascribed to competition between inorganic anions and tetracycline for deposition sites on sand surfaces. However, when Ca2+ was the counterion, the differences in the breakthrough curve of tetracycline among three inorganic anions (i.e., SO42-, NO3- and Cl-) were very small. In this case, the transport-inhibiting effects of anions could be counterbalanced by the transport-enhancement effects of the cation-bridging effect. Also, the two-site nonequilibrium transport model was applied to analyze the transport data. Findings from this study improve our understanding of the transport of tetracycline in saturated aquifer materials.


Assuntos
Ânions/química , Cátions Bivalentes/química , Modelos Teóricos , Dióxido de Silício/química , Tetraciclina/análise , Poluentes Químicos da Água/análise , Adsorção , Porosidade , Tetraciclina/química , Poluentes Químicos da Água/química
19.
RSC Adv ; 9(69): 40565-40576, 2019 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-32215205

RESUMO

Nanocellulose, which can be derived from any cellulosic biomass, has emerged as an appealing nanoscale scaffold to develop inorganic-organic nanocomposites for a wide range of applications. In this study, titanium dioxide (TiO2) nanocrystals were synthesized in the cellulose nanocrystal (CNC) scaffold using a simple approach, i.e., hydrolysis of a titanium oxysulfate precursor in a CNC suspension at low temperature. The resulting TiO2 nanoparticles exhibited a narrow size range between 3 and 5 nm, uniformly distributed on and strongly adhered to the CNC surface. The structure of the resulting nanocomposite was evaluated by transmission electron microscopy (TEM) and X-ray diffraction (XRD) methods. The growth mechanism of TiO2 nanocrystals in the CNC scaffold was also investigated by solution small-angle X-ray scattering (SAXS), where the results suggested the mineralization process could be described by the Lifshitz-Slyozov-Wagner theory for Ostwald ripening. The demonstrated TiO2/CNC nanocomposite system exhibited excellent performance in dye degradation and antibacterial activity, suitable for a wide range of environmental remediation applications.

20.
J Affect Disord ; 243: 360-365, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30266027

RESUMO

BACKGROUND: Previous studies about comorbidity have primarily focused on disorders based on diagnostic criteria instead of symptoms. This study aimed to describe the prevalence and risk factors of anxiety comorbid depression based on a population-based sample in Chifeng City Inner Mongolia and explored the gender differences of depressive subtypes in anxiety patients. METHODS: This study was a cross-sectional study conducted among 6376 community residents. Logistics analysis and multiple-group latent class analysis was used in exploring the risk factors and subtypes of anxiety comorbid depressive symptoms. RESULTS: A total of 4528 respondents were interviewed in this study. The lifetime prevalence estimates for anxiety in the total sample was 5.70%. Among residents who had ever had anxiety, most of them reported having depressive symptoms while 15.79% of them met the criteria of MDD. Logistics analysis showed childhood adversities were associated with anxiety comorbid depressive symptoms. The results of multiple-group latent class analysis showed that the latent class probabilities were different between males and females. CONCLUSION: The prevalence rates of comorbidity were similar to the reports of previous regional surveys in China with statistically significant differences of comorbidity occurring between males and females. Precision prevention should therefore be targeted towards different kinds of populations.


Assuntos
Transtornos de Ansiedade/epidemiologia , Transtorno Depressivo Maior/epidemiologia , Adulto , Ansiedade/epidemiologia , China/epidemiologia , Comorbidade , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Análise de Classes Latentes , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Sexuais
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