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1.
J Environ Sci (China) ; 146: 217-225, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38969449

RESUMO

Membrane fouling is a bottleneck issue that hindered the further application of ultrafiltration technology. To alleviate membrane fouling, coagulation-ultrafiltration (C-UF) process using polyaluminum chloride (PACl) and PACl-Al13 with high proportion of Al13O4(OH)247+ as coagulants, respectively, were investigated at various pH conditions. Results indicated that an increase in solution pH contributed to larger floc size and looser floc structure for both PACl and PACl-Al13. It was conducive to the formation of more porous cake, as evidenced by mean pore area and pore area distribution of cake, leading to lower reversible fouling. Furthermore, humic acid (HA) removal presented a trend of first increasing and then decreasing with the increase of pH. The optimal HA removal was achieved at pH 6 regardless of coagulant type, suggesting that the slightest irreversible fouling should be occurred at this point. Interestingly, the irreversible fouling with PACl coagulant achieved a minimum value at pH 9, while the minimal irreversible fouling with PACl-Al13 was observed at pH 6. We speculated that the cake formed by PACl could further intercept HA prior to UF process at alkaline pH. Furthermore, compared with PACl, PACl-Al13 had a stronger charge neutralization ability, thus contributing to more compact floc structure and higher HA removal at various pH conditions. By UF fractionation measurement, higher HA removal for PACl-Al13 was due to higher removal of HA with molecular weight less than 50 kDa.


Assuntos
Substâncias Húmicas , Membranas Artificiais , Ultrafiltração , Ultrafiltração/métodos , Substâncias Húmicas/análise , Floculação , Hidróxido de Alumínio/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Eliminação de Resíduos Líquidos/métodos
2.
Org Biomol Chem ; 21(15): 3073-3078, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36786411

RESUMO

Herein we describe a self-acid-enabled chemo-, regio-, and stereospecific cis-hydrophenoxylation of ynamides under reagent-free conditions. The presence of a non-polar solvent such as toluene was found to be beneficial to facilitate the rate-limiting proton transfer between phenols and ynamides to form an intimate ion pair, which is followed by a swift nucleophilic attack of the phenolate oxygen on keteniminium, fulfilling the overall hydrofunctionalization event. This protocol is operationally simple and easily scalable, tolerates a wide variety of functional groups, and shows good compatibility with the requirements of modern green chemistry.

3.
Environ Res ; 212(Pt B): 113285, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35483411

RESUMO

The mechanisms governing interactions among various natural organic matter (NOM) fractions and the subsequently impact on ultrafiltration process have not been systematically studied. In this work, bovine serum albumin (BSA), humic acid (HA), sodium alginate (SA) were applied as model NOM to explore the influence of the interactions among NOM on ultrafiltration process. Results indicated that tryptophan-like fluorescence fraction was the dominant reaction fraction of HA to react with SA and BSA. Different interactions among model NOM not only changed the interception order of fluorescence fractions by ultrafiltration from fulvic acid-like, humic-like and tryptophan-like in BSA/HA mixture to tryptophan-like, humic-like and fulvic acid-like in BSA/HA/SA/kaolin mixture, but also remarkably influence the membrane fouling behavior. In BSA/HA mixture, new-generated aggregates with molecular weight (MW) of 10 kDa could not pass though ultrafiltration membrane and mainly contributed to chemical reversible fouling. In BSA/HA/SA mixture, SA simultaneously reacted with BSA and HA to generate aggregates with larger MW which could be washed down by physical cleaning. In BSA/HA/SA/kaolin mixture, the aggregates with MW of 10 kDa and chemical reversible fouling were disappeared due to the adsorption role of kaolin. These findings could further improve our understanding regarding membrane fouling mechanisms of raw water with different components.


Assuntos
Ultrafiltração , Purificação da Água , Alginatos/química , Substâncias Húmicas/análise , Caulim/química , Membranas Artificiais , Soroalbumina Bovina/química , Triptofano , Ultrafiltração/métodos , Purificação da Água/métodos
4.
Phys Chem Chem Phys ; 21(38): 21438-21444, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31531470

RESUMO

Magnon-driven interfacial magnetoelectric coupling in Co/PMN-PT multiferroic heterostructures is investigated at room temperature. The electric field controlled ferromagnetic resonance field possesses a loop-like curve, with a large resonance field shift between positive and negative remanent polarizations, which confirms a non-volatile strong magnetoelectric coupling. However, with a non-magnetic Ta layer inserted at the Co/PMN-PT interface, a piezostrain-induced butterfly-like curve of the resonance field versus applied electric field of the Co/Ta/PMN-PT multiferroic heterostructure is observed. Further, the non-volatile behavior of the resonance field changing with the applied electric field can be obtained, consistent with the result of polarization versus applied electric field curve, which can be attributed to the magnon-driven interfacial magnetoelectric coupling, showing a strong correlation of magnetization of Co thin film and the polarization of PMN-PT. The result is promising for the design of future multiferroic devices.

6.
Nat Commun ; 15(1): 7428, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198391

RESUMO

Considering the indispensable significance and utilities of meta-substituted pyridines in medicinal, chemical as well as materials science, a direct meta-selective C-H functionalization of pyridines is of paramount importance, but such reactions remain limited and highly challenging. In general, established methods for meta C-H functionalization of pyridines rely on the utilization of tailored electrophilic reagents to realize the intrinsic polarity match. Herein, we report a complementary electrochemical methodology; diverse nucleophilic sulfinates allow meta-sulfonylation of pyridines through a redox-neutral dearomatization-rearomatization strategy by a tandem dearomative cycloaddition/hydrogen-evolution electrooxidative C-H sulfonation of the resulting oxazino-pyridines/acid-promoted rearomatization sequence. Besides, several salient features, including exclusive regiocontrol, remarkable substrate/functional group compatibility, scale-up potential, and facile late-stage modification, have been demonstrated, which further contributes to the practicality and adaptability of this approach.

7.
J Affect Disord ; 361: 674-683, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38908554

RESUMO

Administration mode of patient-reported outcome measures (PROMs) may influence responses. We assessed if Patient Health Questionnaire-9 (PHQ-9), Edinburgh Postnatal Depression Scale (EPDS) and Hospital Anxiety and Depression Scale - Depression subscale (HADS-D) item responses and scores were associated with administration mode. We compared (1) self-administration versus interview-administration; within self-administration (2) research or medical setting versus private; and (3) pen-and-paper versus electronic; and within interview-administration (4) in-person versus phone. We analysed individual participant data meta-analysis datasets with item-level data for the PHQ-9 (N = 34,529), EPDS (N = 16,813), and HADS-D (N = 16,768). We used multiple indicator multiple cause models to assess differential item functioning (DIF) by administration mode. We found statistically significant DIF for most items on all measures due to large samples, but influence on total scores was negligible. In 10 comparisons conducted across the PHQ-9, EPDS, and HADS-D, Pearson's correlations and intraclass correlation coefficients between latent depression symptom scores from models that did or did not account for DIF were between 0.995 and 1.000. Total PHQ-9, EPDS, and HADS-D scores did not differ materially across administration modes. Researcher and clinicians who evaluate depression symptoms with these questionnaires can select administration methods based on patient preferences, feasibility, or cost.


Assuntos
Questionário de Saúde do Paciente , Escalas de Graduação Psiquiátrica , Humanos , Feminino , Escalas de Graduação Psiquiátrica/normas , Medidas de Resultados Relatados pelo Paciente , Psicometria , Depressão/diagnóstico , Depressão/psicologia , Adulto , Depressão Pós-Parto/diagnóstico , Depressão Pós-Parto/psicologia , Inquéritos e Questionários/normas
8.
Food Chem ; 429: 136919, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37494754

RESUMO

A functional bipolar electrode-electrochemiluminescence (BPE-ECL) platform based on biocathode reducing oxygen was constructed for detecting electrochemically active bacteria (EAB) in this paper. Firstly, thiolated trimethylated chitosan quaternary ammonium salt (TMC-SH) layer was assembled on the gold-plated cathode of BPE. TMC-SH contains quaternary ammonium salt branch chain, which can inhibit the growth of microorganisms on the surface or in the surrounding environment while absorbing bacteria. Then, the peristaltic pump was used to flow all of the samples through the cathode, and the EAB was electrostatically adsorbed on the electrode surface. Finally, applying a constant potential to the BPE, bacteria can catalyze electrochemical reduction of O2, and decrease the overpotential of O2 reduction at the cathode, which in turn generates an ECL reporting intensity change at the anode. In this way, live and dead bacteria can be distinguished, and the influence of complex food substrates on detection can be greatly reduced.


Assuntos
Compostos de Amônio , Técnicas Biossensoriais , Medições Luminescentes , Técnicas Eletroquímicas , Eletrodos
9.
Artigo em Inglês | MEDLINE | ID: mdl-37489073

RESUMO

OBJECTIVE: To evaluate the degree that the Cochin Hand Function Scale (CHFS) generates scores that are comparable across language, sex, and disease subtype. METHODS: We included participants enrolled in the Scleroderma Patient-centered Intervention Network (SPIN) Cohort who completed the CHFS at their baseline assessment between April 2014 and September 2020. Confirmatory factor analysis (CFA) was used to test unidimensionality, and multiple indicator multiple cause (MIMIC) models were used for differential item functioning (DIF) analysis based on language, sex, and disease subtype. Both intraclass correlation coefficient (ICC) and Pearson's correlation were calculated using factor scores obtained from unadjusted and DIF-adjusted MIMIC models to evaluate agreement and correlation between scores. RESULTS: A total of 2,155 participants were included. CFA with covarying error terms supported a good fit of the model (χ2 [127] = 1,754.671; P < 0.001; Tucker-Lewis index = 0.985; comparative fit index = 0.987; root mean square error of approximation = 0.077). Nine items displayed statistically significant DIF for language of administration, 10 items for sex, and 10 items for disease subtype. However, the overall impact of DIF was negligible when comparing factor scores that did and did not account for DIF (ICC = 0.999; r = 0.999). CONCLUSION: The CHFS has score comparability in systemic sclerosis regardless of participants' language, sex, and disease subtype.

10.
Polymers (Basel) ; 14(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36080694

RESUMO

The mechanical properties of epoxy resin can be enhanced by adding nanofillers into its matrix. This study researches and compares the impacts of adding nanofillers with different dimensions, including two-dimensional boron nitride and zero-dimensional silica, on the mechanical and toughness properties of epoxy resin. At low fractions (0-2.0 wt%), 2DBN/epoxy composites have a higher Young's modulus, fracture toughness and critical strain energy release rate compared to SiO2/epoxy composites. However, the workability deteriorated drastically for BN/epoxy composites above a specific nanofiller concentration (2.0-3.0 wt%). BN prevents crack growth by drawing and bridging. SiO2 enhances performance by deflecting the crack direction and forming voids. Additionally, the dimension and content of nanofiller also influence glass transition temperature and storage modulus significantly.

11.
Sci Adv ; 8(51): eade6455, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36563149

RESUMO

The function of robots in extreme environments is regarded as one of the major challenges facing robotics. Here, we demonstrate that acidophilic microalgae biomotors can maintain their swimming behavior over long periods of time in the harsh acidic environment of the stomach, thus enabling them to be applied for gastrointestinal (GI) delivery applications. The biomotors can also be functionalized with a wide range of cargos, ranging from small molecules to nanoparticles, without compromising their ability to self-propel under extreme conditions. Successful GI delivery of model payloads after oral administration of the acidophilic algae motors is confirmed using a murine model. By tuning the surface properties of cargos, it is possible to modulate their precise GI localization. Overall, our findings indicate that multifunctional acidophilic algae-based biomotors offer distinct advantages compared to traditional biohybrid platforms and hold great potential for GI-related biomedical applications.

12.
Phys Chem Chem Phys ; 13(11): 4881-7, 2011 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-21221432

RESUMO

We describe a robust and facile approach to the selective modification of patterned porous films via layer-by-layer (LBL) self-assembly. Positively charged honeycomb-patterned films were prepared from polystyrene-block-poly(N,N-dimethyl-aminoethyl methacrylate) (PS-b-PDMAEMA) and a PS/PDMAEMA blend by the breath figure method followed by surface quaternization. Alginate and chitosan were alternately deposited on the films via LBL self-assembly. The assembly on the PS-b-PDMAEMA film exhibits two stages with different growth rates, as elucidated by water contact angles, fluorescence microscopy, and quartz crystal microbalance results. The assembly can be controlled on the top surface or across all surfaces of the film by changing the number of deposition cycles. We confirm that there exists a Cassie-Wenzel transition with an increase in deposition cycles, which is responsible for the tunable assembly. For the PS/PDMAEMA film, the pores can be completely wetted and the polyelectrolytes selectively assemble inside the pores, instead of on the top surface. The controllable selective assembly forms unique hierarchical structures and opens a new route for surface modification of patterned porous films.


Assuntos
Metacrilatos/química , Nylons/química , Poliestirenos/química , Alginatos/química , Quitosana/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Porosidade
13.
J Craniofac Surg ; 21(6): 1831-3, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21119433

RESUMO

OBJECTIVE: The purpose of this study was to assess the diagnosis, treatment, and prognosis of aggressive fibromatosis in the head and neck. METHODS: This is a retrospective study of patients with aggressive fibromatosis who underwent surgical interventions during the 9-year period from 2001 to 2010. Aggressive fibromatosis is treated by resection with an adequate safety margin. Radiotherapy is given to patient with tumor that cannot be completely removed. RESULTS: Four patients with aggressive fibromatosis were identified under the 2005 World Health Organization classification guidelines, which, here reported, have been surgically treated. The lesions were located in the buccal mucosa in 1 patient, the tongue in 1 patient, and neck in 2 patients. Then, they were all treated by aggressive local resection. One patient who had a partially resected tumor underwent radiotherapy. The follow-up period ranged from 7 to 107 months. CONCLUSIONS: For the cases of tumor that can be completely removed, the prognosis is excellent. Otherwise, the tumor is vulnerable to relapse. We recommend radiotherapy in patients who have unresectable or partially resected tumor when the tumor is adjacent to vital structures. Patients with aggressive fibromatosis should remain in long-term follow-up.


Assuntos
Fibromatose Agressiva/cirurgia , Neoplasias de Cabeça e Pescoço/cirurgia , Adulto , Idoso , Feminino , Fibromatose Agressiva/diagnóstico , Seguimentos , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/cirurgia , Neoplasias Bucais/cirurgia , Terapia Neoadjuvante , Recidiva Local de Neoplasia/cirurgia , Neoplasia Residual , Radioterapia Adjuvante , Estudos Retrospectivos , Neoplasias da Língua/cirurgia , Resultado do Tratamento
14.
Sci Rep ; 10(1): 14347, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873837

RESUMO

Magnon-tuning non-volatile magnetic dynamics is investigated in a CoZr/PMN-PT structure by measuring ferromagnetic resonance at room temperature. The electric-field control of ferromagnetic resonance shows loop-like behavior, which indicates non-volatile electric-field control of the magnetism. Further, fitting the curves of in-plane rotating angle versus ferromagnetic resonance field under different electric fields shows that the effective magnetic field changes in loop-like manner with the electric field. The resulting change in non-volatile saturation magnetization with electric field is consistent with that of a polarization electric field curve. A 1.04% change of saturation magnetization is obtained, which can be attributed to a magnon-driven magnetoelectric coupling at the CoZr/PMN-PT interface. This magnon-driven magnetoelectric coupling and its dynamic magnetic properties are significant for developing future magnetoelectric devices.

15.
J BUON ; 24(1): 130-135, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30941961

RESUMO

PURPOSE: The prime objective of the present study was to investigate the anticancer properties of angustifoline against COLO-205 human colon cancer cells. Its effects on cell autophagy, apoptosis, cell invasion and cell migration, and cell cycle arrest were also evaluated in the current study. METHODS: WST-1 assay was used to study cytotoxic effects of the compound on the cell viability. Effects on apoptosis and cell cycle arrest were evaluated by flow cytometry. In vitro wound healing assay and matrigel assay were carried out to study the effects of angustifoline on cell migration and cell invasion respectively. To confirm autophagy, we evaluated the expression of several autophagy-associated proteins using Western blot assay along with transmission electron microscopy (TEM). RESULTS: The findings indicated that angustifoline induced dose- and time-dependent cytotoxicity in COLO-205 human colon cancer cells along with inhibiting cancer cell colony formation. Angustifoline-treated cells exhibited cell shrinkage along with distortion of the normal cell morphology. Angustifoline-treated cells were also arrested in the G2/M phase of the cell cycle, showing strong dose-dependence. The compound also led to inhibition of cell migration and cell invasion. The results showed that treatment of these cells led to generation of autophagic cell vesicles. Furthermore, it was observed that the expression of Beclin-1 and LC3-II proteins was significantly upregulated in the angustifoline-administered COLO-205 cells. CONCLUSIONS: In brief, the present study hints towards the potent anticancer potential of the natural product angustifoline against COLO-205 human colon cancer cells with in depth mechanistic studies.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia , Movimento Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Esparteína/análogos & derivados , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Esparteína/farmacologia , Células Tumorais Cultivadas
16.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 31(5): 472-5, 2013 Oct.
Artigo em Zh | MEDLINE | ID: mdl-24298796

RESUMO

OBJECTIVE: To study the relationship between velopharyngeal morphology and velopharyngeal function in operated cleft palate patients with velopharyngeal competence (VPC) with levator veli palatini retropositioning according to Sommerlad. METHODS: Three groups were included in the study. The experimental group comprised 18 incomplete cleft patients (group T1) repaired with VPC repaired with levator veli palatini retropositioning according to Sommerlad and 14 incomplete cleft patients (group T2) with velopharyngeal incompetence (VPI) repaired with Langenbeck's technique. The control group was composed of 13 normal adults. The outcome of the velopharyngeal function by nasopharyngoscopy and lateral cephalogram was assessed. Skeletal landmarks and measurements were derived from the tracing of lateral cephalograms. The measurements included velar length, pharyngeal depth, and adequate ratio of velar length to pharyngeal depth. The cranial base, cervical vertebrae, posterior nasal spine, and the position of the posterior pharyngeal wall (PPW) in the pharyngeal triangle were also analyzed. All data were subjected to student's t-test of statistical significance. RESULTS: All 18 subjects in group T1 obtained complete velopharyngeal closure. Velopharyngeal closure in seven, five, and two subjects in group T2 was 70%, 50% to 70%, and less than 50%, respectively, according to the results of nasopharyngoscopy. The lateral velar length (25.7 mm + 2.3 mm) in group T1 was similar to that of the control group (29.9 mm + 2.7 mm) (P > 0.05). The pharyngeal depth in group T1 was shorter than that in the other two groups, and the adequate ratio (1.43 + 0.26) was similar to that in the normal group (1.45 + 0.26). Group T2 had a significantly short velar length (22.9 mm + 2.3 mm) and normal pharyngeal depth, resulting in a small length/depth ratio (0.95 + 0.14) than that in group T1 and the control group. PPW in the pharyngeal triangle was positioned superiorly in group T2 compared with the control group. CONCLUSION: The velopharyngeal morphology of operated cleft palate patients with VPC with levator veli palatini retropositioning according to Sommerlad was found to be similar to that of the normal control group. VPI cleft palate patients are characterized by a shorter palate, smaller adequate ratio (< 1.0), slightly counterclockwise-rotated pharyngeal triangle, and superiorly positioned PPW.


Assuntos
Fissura Palatina , Palato Mole , Adulto , Humanos , Músculos Palatinos , Faringe , Insuficiência Velofaríngea
17.
Chemosphere ; 76(5): 721-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19427660

RESUMO

The effects of water vapor on the activity of the copper based catalysts with different supports such as CuO/gamma-Al2O3, CuO/SiO2 and CuO/TiO2 for styrene combustion were investigated. The catalytic activity of the catalysts was tested in the absence of and presence of water vapor and the catalysts were characterized. Temperature programmed desorption (TPD) experiments and diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) measurements were conducted in order to estimate and explain the water effects. Results showed that the existence of water vapor had a significant negative effect on the catalytic activity of these copper based catalysts due to the competition adsorption of water molecule. DRIFTS studies showed that the catalyst CuO/gamma-Al2O3 had the strongest adsorption of water, while the catalyst CuO/TiO2 had the weakest adsorption of water. H2O-TPD studies also indicated that the order of desorption activation energies of water vapor on the catalysts or the strength of interactions of water molecules with the surfaces of the catalysts was CuO/gamma-Al2O3>CuO/SiO2>CuO/TiO2. As a consequence of that, the CuO/TiO2 exhibited the better durability to water vapor, while CuO/gamma-Al2O3 had the poorest durability to water vapor among these three catalysts.


Assuntos
Cobre/química , Estireno/química , Água/química , Adsorção , Óxido de Alumínio/química , Catálise , Difusão , Dióxido de Silício/química , Temperatura , Titânio/química , Volatilização , Difração de Raios X
18.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 25(4): 251-4, 2009 Jul.
Artigo em Zh | MEDLINE | ID: mdl-19873711

RESUMO

OBJECTIVE: To investigate the application of titanium mesh and free forearm flap for reconstruction of maxillary defect resulted from tumor resection. METHODS: From 2004 to 2008, 19 cases with maxillary tumor underwent tumor resection. The defects were reconstructed immediately with titanium mesh for bony defects and free forearm flap for oral mucosa defects. RESULTS: 16 cases achieved satisfactory functional and cosmetic results. The speech assessment was good without oronasal reflux. The titanium mesh was exposed and infected in 3 cases. Then the meshes were taken out and the defects were covered with the forearm flap to close the oronasal fistula. The midface was slightly depressed with no functional morbidity. CONCLUSIONS: It is simple and practical to reconstruct maxillary defect with titanium mesh and free forearm flap. Both the functional and cosmetic results are satisfactory.


Assuntos
Antebraço/cirurgia , Transplante de Pele , Retalhos Cirúrgicos , Telas Cirúrgicas , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Neoplasias Maxilares/cirurgia , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Titânio , Adulto Jovem
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