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1.
Small ; : e2405909, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363818

RESUMO

Composite solid electrolytes (CSEs) have become one of the most promising solid-state electrolytes due to their favorable safety and flexibility. However, the weak interaction between inorganic fillers and polymer matrix leads to poor organic-inorganic interfacial compatibility, which degrades the electrochemical performance of CSEs. Herein, it is demonstrated that Li6.4La3Zr1.4Ta0.6O12 (LLZTO) can be chemically bonded to the polymer matrix by surface coordination of the 1,2-dithiolane group of lipoic acid (LA) with metal atoms on the surface of LLZTO through a combination of experimental investigations and theoretical calculations. The surface coordination not only enhances the interfacial compatibility between LLZTO and the polymer matrix, but also facilitates rapid Li+ transport, which leads to the ionic conductivity of the prepared CSE (P-V-M@LLZTO) as high as 6.1 × 10-4 S cm-1 at 30 °C. The excellent interface compatibility ensures a stable cycle of Li/P-V-M@LLZTO/Li symmetrical cell for more than 3500 h. As a result, LiFePO4/P-V-M@LLZTO/Li cell delivers the discharge capacity of 161 mAh g-1 after 5 cycles with a capacity retention of 81% after 500 cycles at 0.5C under 30 °C. This work demonstrates that surface coordination is an effective strategy to solve the inherent interfacial incompatibility problem in CSEs.

2.
Plant Physiol ; 193(4): 2768-2787, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37648267

RESUMO

The efficient infection of plants by the bacteria Xanthomonas campestris pv. campestris (Xcc) depends on its type III effectors (T3Es). Although the functions of AvrE family T3Es have been reported in some bacteria, the member XopAM in Xcc has not been studied. As XopAM has low sequence similarity to reported AvrE-T3Es and different reports have shown that these T3Es have different targets in hosts, we investigated the functions of XopAM in the Xcc-plant interaction. Deletion of xopAM from Xcc reduced its virulence in cruciferous crops but increased virulence in Arabidopsis (Arabidopsis thaliana) Col-0, indicating that XopAM may perform opposite functions depending on the host species. We further found that XopAM is a lipase that may target the cytomembrane and that this activity might be enhanced by its membrane-targeted protein XOPAM-ACTIVATED RESISTANCE 1 (AMAR1) in Arabidopsis Col-0. The binding of XopAM to AMAR1 induced an intense hypersensitive response that restricted Xcc proliferation. Our results showed that the roles of XopAM in Xcc infection are not the same as those of other AvrE-T3Es, indicating that the functions of this type of T3E have differentiated during long-term bacterium‒host interactions.


Assuntos
Arabidopsis , Xanthomonas campestris , Arabidopsis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Membrana/metabolismo , Virulência , Fatores de Virulência/metabolismo , Doenças das Plantas/microbiologia
3.
Eur J Oral Sci ; 132(1): e12966, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38062539

RESUMO

The objective of this study was to determine the effects on the colour of adding increasing concentrations of graphene to orthodontic fixed retainer adhesives and to evaluate changes in optical transmission during light curing and the resultant degree of conversion. Two different types of adhesives commonly used for fixed retainers were investigated: A packable composite (Transbond) and a flowable composite (Transbond Supreme). Graphene was added to the adhesives in three different concentrations (0.01, 0.05, and 0.1 wt%). Adhesives without graphene addition were set as control groups. A Minolta colourimeter was used to measure the colour and translucency parameters. Irradiance transmitted during curing was quantified using MARC Light Collector. Fourier-transform infrared spectroscopy was used to record degree of conversion. Data were statistically analysed with the Student's t-test and one-way ANOVA with Tukey's tests (α = 0.05). The findings showed that incorporating graphene darkened the adhesive colour significantly and reduced translucency. As the graphene concentration reached 0.1 wt%, samples became opaque; yet, no adverse effect on degree of conversion was observed. The addition of graphene reduces optical transmission of lingual retainer adhesives; the effect increases with graphene concentration.


Assuntos
Bis-Fenol A-Glicidil Metacrilato , Colagem Dentária , Grafite , Cimentos Dentários , Cimentos de Resina/química , Teste de Materiais , Resinas Compostas/química , Adesivos/química
4.
BMC Public Health ; 24(1): 292, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267909

RESUMO

BACKGROUND: High rates of health inequalities and chronic non-communicable diseases exist amongst the prison population. This places people in and/or released from prison at heightened risk of multimorbidity, premature mortality, and reduced quality of life. Ensuring appropriate healthcare for people in prison to improve their health outcomes is an important aspect of social justice. This review examines the global literature on healthcare interventions to detect, monitor and manage chronic non-communicable diseases amongst the prison population and people recently released from prison. METHODS: Systematic searches of EMBASE, MEDLINE, CINAHL, Web of Science, Scopus, and the Cochrane Library were conducted and supplemented by citation searching and review of the grey literature. The literature searches attempted to identify all articles describing any healthcare intervention for adults in prison, or released from prison in the past 1 year, to detect, monitor, or manage any chronic non-communicable illness. 19,061 articles were identified, of which 1058 articles were screened by abstract and 203 articles were reviewed by full text. RESULTS: Sixty-five studies were included in the review, involving 18,311 participants from multiple countries. Most studies were quasi-experimental and/or low to moderate in quality. Numerous healthcare interventions were described in the literature including chronic disease screening, telemedicine, health education, integrated care systems, implementing specialist equipment and staff roles to manage chronic diseases in prisons, and providing enhanced primary care contact and/or support from community health workers for people recently released from prison. These interventions were associated with improvement in various measures of clinical and cost effectiveness, although comparison between different care models was not possible due to high levels of clinical heterogeneity. CONCLUSIONS: It is currently unclear which interventions are most effective at monitoring and managing chronic non-communicable diseases in prison. More research is needed to determine the most effective interventions for improving chronic disease management in prisons and how these should be implemented to ensure optimal success. Future research should examine interventions for addressing multimorbidity within prisons, since most studies tested interventions for a singular non-communicable disease.


Assuntos
Doenças não Transmissíveis , Prisões , Adulto , Humanos , Agentes Comunitários de Saúde , Doenças não Transmissíveis/terapia , Qualidade de Vida
5.
Phys Chem Chem Phys ; 25(6): 4803-4809, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36692367

RESUMO

The exploration of efficient single-atom catalysts provides a prospective pattern for the sustainable development of electrocatalytic nitrogen fixation. We systematically researched the nitrogen reduction properties of catalysts with a single transition metal (TM) atom sandwiched between BN-doped graphdiyne and graphdiyne (labeled BN-TM-G) by first-principles calculations. The TM atom in the novel sandwich structure provides electrons to the adjacent B atom, which acts as the active site, thus driving the fixation and reduction of N2. In the BN-TM-G system, the NRR catalytic activity is bound up with the positive charge polarization level of the TM atom. Among them, BN-Sc-G, BN-Ti-G, BN-V-G, and BN-Cr-G systems showed higher catalytic ability, and the competitive HER was inhibited. In particular, the lowest limiting potential of BN-Cr-G is -0.63 V is promising for the NRR catalyst.

6.
Sensors (Basel) ; 23(11)2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37299903

RESUMO

The core of eLoran ground-based timing navigation systems is the accurate measurement of groundwave propagation delay. However, meteorological changes will disturb the conductive characteristic factors along the groundwave propagation path, especially for a complex terrestrial propagation environment, and may even lead to microsecond-level propagation delay fluctuation, seriously affecting the timing accuracy of the system. Aiming at this problem, this paper proposes a propagation delay prediction model based on a Back-Propagation neural network (BPNN) for a complex meteorological environment, which realizes the function of directly mapping propagation delay fluctuation through meteorological factors. First, the theoretical influence of meteorological factors on each component of propagation delay is analyzed based on calculation parameters. Then, through the correlation analysis of the measured data, the complex relationship between the seven main meteorological factors and the propagation delay, as well as their regional differences, are demonstrated. Finally, a BPNN prediction model considering regional changes of multiple meteorological factors is proposed, and the validity of the model is verified by long-term collected data. Experimental results show that the proposed model can effectively predict the propagation delay fluctuation in the next few days, and its overall performance is significantly improved compared with that of the existing linear model and simple neural network model.


Assuntos
Conceitos Meteorológicos , Redes Neurais de Computação , Modelos Lineares , Coleta de Dados
7.
Eur J Orthod ; 45(6): 645-661, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-37824794

RESUMO

OBJECTIVES: To systematically assess the scientific literature for the prevalence of failure rate of fixed orthodontic bonded retainer (FOBR). METHOD: Randomized clinical trials (RCTs) and prospective non-RCTs involving participants who had FOBR fitted were included. The Cochrane Central Register of Controlled Trials, Web of science, MEDLINE, and EMBASE via OVID were searched from inception to January 2023. Risk of bias was assessed using the Cochrane RoB 2 and Newcastle-Ottawa tools. The main outcome was the failure rate of FOBRs. The secondary outcome was to identify factors that can influence the failure of FOBR. Meta-analyses and sensitivity analyses were undertaken using Revman, version5.4. A random-effects model was used. Quality assessment using Grading of Recommendations Assessment, Development, and Evaluation. RESULTS: Thirty-four studies (25 RCTs and 9 prospective clinical studies) (3484 participants) were included in this review. The overall failure rate of bonded retainers, after excluding high-risk studies, was 35.22% (95% confidence interval [CI] 27.46-42.98). The failure rate is increased with the duration of follow up; with short-term follow-up rate 24.18% (95% CI 20.16-28.21), medium-term follow up 40.09% (95% CI 30.92-49.26), and long-term follow up 53.85% (95% CI 40.31-67.39). There is a low level of evidence to suggest there is no statistically significant difference in the failure rate of fixed retainers using direct versus indirect bonding methods, using liquid resin versus without liquid resin, and fibre-reinforced composite retainers compared to multi-stranded stainless steel retainers. DISCUSSION: There is low-quality evidence to suggest that the failure rate of FOBR is relatively high. There is a need for high-quality, well-reported clinical studies to assess factors that can influence the failure rate of FOBR. REGISTRATION: CRD42021190910.


Assuntos
Aparelhos Ortodônticos Fixos , Contenções Ortodônticas , Humanos , Prevalência , Estudos Prospectivos , Aço Inoxidável
8.
Sci Educ (Dordr) ; : 1-32, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37359259

RESUMO

Science educators report that students struggle with understanding, using, and evaluating the evidence underpinning scientific knowledge. However, there are not many studies focused on helping instructors address those difficulties. Here, we report on a laboratory instructor's scaffolding of students' evidentiary reasoning with and about evidence for evolutionary trees with guidance from the Conceptual Analysis of Disciplinary Evidence (CADE) framework, which links biological knowledge with epistemic considerations. To consider both domain-general and discipline-specific aspects of evidence, CADE was implemented to inform scaffolds in two ways: (1) generic evidence scaffolds (GES) reminded students of general epistemic considerations; (2) disciplinary evidence scaffolds (DES) explicitly reminded students of the disciplinary knowledge of relevance for considering biological evidence. An instructor's lab discussions were compared before and after they had a workshop with CADE. CADE helped the lab instructor facilitate students' evidentiary reasoning about evolutionary trees. In comparison to baseline, both GES and DES discussions covered more aspects and relationships among types of evidence for evolutionary tree-thinking and the instructor prompted more kinds of general epistemic considerations and biological knowledge. DES discussions emphasized the importance of disciplinary knowledge for research design. The CADE framework guided planning and implementation of intentional scaffolding aimed at guiding evidentiary reasoning. Supplementary Information: The online version contains supplementary material available at 10.1007/s11191-023-00435-6.

9.
Am J Orthod Dentofacial Orthop ; 162(5): 601-615.e2, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36031511

RESUMO

INTRODUCTION: Orthodontic fixed retainers are preferred as they depend less on patient compliance. Recently, researchers tried to use fiber-reinforced composite (FRC) to replace the multistranded stainless-steel wire (MSW) of the fixed retainers to enhance the mechanical properties and esthetics. This systematic review aimed to analyze the effectiveness of the FRC retainers. METHODS: We searched the electronic databases (May 1, 2021), including Medline, the Cochrane Library, EMBASE, PubMed, Web of Science, and CINAHL. We applied no language or date restrictions in the searches of the databases. Only randomized controlled trials (RCTs) and prospective clinical controlled trials were included. The revised Cochrane risk of bias tool for randomized trials and risk of bias in nonrandomized studies of interventions were used to evaluate the risk of bias in RCTs and non-RCTs, respectively. The outcomes were pooled using Review Manager 5.4. The primary outcome of this review was teeth relapse, and the secondary outcomes were bonded retainer failure rate, adverse effect on oral health, and patient's satisfaction. RESULTS: Eleven out of 99 studies, which included 873 participants, were used in this review, with the follow-up ranging from 6 months to 6 years. Ten studies compared the FRC retainers with MSW retainers, and 1 study compared FRC retainers with a different fiber material. Ten studies were RCT, and 1 was non-RCT. There was 0.39 less relapse with the FRC retainers than with MSW retainers (mean difference, -0.39; 95% confidence interval [CI], -0.41 to -0.37; P <0.00001). There was no statistically significant difference in the failure rate between the FRC and MSW with the whole retainer as an outcome unit risk ratio of 1.72 (95% CI, 0.57-5.14; P = 0.33) or with the teeth an as outcome unit risk ratio of 0.85 (95% CI, 0.47-1.52; P = 0.58). There was insufficient evidence to conduct the meta-analysis of the adverse effect on oral health and patient satisfaction. CONCLUSIONS: Low-quality evidence is available to suggest that the effectiveness of the FRC is comparable to the MSW with no significant difference in the failure rate. However, we have very low certainty on these results. It is worth conducting future robust clinical studies to assess the effectiveness of FRC retainers with long follow-up.

10.
Chemistry ; 27(63): 15562, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34730261

RESUMO

Invited for the cover of this issue are Ken Sakata, Yoshiaki Nishibayashi, and co-workers at The University of Tokyo and Toho University. The image depicts the propargylic substitution reaction of a propargylic alcohol with an N-monosubstituted hydrazone, where the nucleophilicity of the hydrazone is controlled by the choice of catalytic system. Read the full text of the article at 10.1002/chem.202103287.


Assuntos
Rutênio , Catálise , Cobre , Humanos , Hidrazonas
11.
Chemistry ; 27(63): 15650-15659, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34606139

RESUMO

Ruthenium- and copper-catalyzed propargylic substitution reactions of propargylic alcohol derivatives with N-monosubstituted hydrazones as ambident nucleophiles are achieved in which N-monosubstituted hydrazones exhibit impressive different reactivities depending on different catalytic systems, behaving as carbon-centered nucleophiles to give the corresponding propargylic alkylated products in ruthenium catalysis, or as nitrogen-centered nucleophiles to afford the corresponding propargylic aminated products in copper catalysis. DFT calculations were carried out to investigate the detailed reaction pathways of these two systems. Further transformation of propargylic substituted products affords the corresponding multisubstituted pyrazoles as cyclization products in good to high yields.

12.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3592-3598, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34402282

RESUMO

Thirteen compounds were isolated and purified from the leaves of Cinnamomum camphora by the macroporous resin,silica gel,and Sephadex LH-20 column chromatographies. Those compounds were further identified by IR,UV,MS,and NMR techniques:( 2 S)-1-( 3″,4″-methylenedioxy phenyl)-3-( 2',6'-dimethoxy-4'-hydroxyphenyl)-propan-2-ol( 1),( 2 R,3 R)-5,7-dimethoxy-3',4'-methylenedioxy flavanol( 2),9-hydroxysesamin( 3),sesamin( 4),piperitol( 5),kobusin( 6),(-)-aptosimon( 7),acuminatolide( 8),1ß,11-dihydroxy-5-eudesmene( 9),lasiodiplodin( 10),vanillin( 11),p-hydroxybenzaldehyde( 12),and p-hydroxybenzoic acid ethyl ester( 13). Compound 1 was a novel compound,and compounds 2,6,7,9 and 10 were isolated from Cinnamomum plants for the first time. Compounds 4,7 and 10 were found to possess good inhibitory effect on IL-6 production in LPS-induced BV2 cells at a concentration of 20 µmol·L-1 in the in vitro bioassay,with inhibition rates of 51. 26% ± 4. 13%,67. 82% ± 3. 77% and85. 81%±1. 19%,respectively.


Assuntos
Cinnamomum camphora , Cinnamomum , Anti-Inflamatórios/farmacologia , Folhas de Planta
13.
Angew Chem Int Ed Engl ; 60(20): 11231-11236, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33826795

RESUMO

The development of transition metal-catalyzed enantioselective propargylic substitution reactions has gained much progress in recent years, however, no successful example with phosphorus-centered nucleophiles has yet been reported until now. Herein, we report the first successful example of ruthenium-catalyzed enantioselective propargylic substitution reactions of propargylic alcohols with diarylphosphine oxides as phosphorus-centered nucleophiles. This synthetic approach provides a new method to prepare chiral phosphorus-containing organic compounds.

14.
Mol Plant Microbe Interact ; 31(9): 932-939, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29522378

RESUMO

Riboswitches are RNA elements that sense metabolites and control gene expression. Recently, the yybP-ykoY riboswitches were found to sense manganese (Mn2+) and regulate the expression of diverse genes. Here, we show that the leader RNA (a yybP-ykoY RNA) of yebN in Xanthomonas oryzae pv. oryzae also functions as a sensor of Mn2+. This leader RNA detects Mn2+ levels in plants and is essential to X. oryzae pv. oryzae virulence. Our data also indicate that Mn2+ is not only required as a microelement for plant growth but also acts as a defense molecule to inhibit pathogen growth. This finding highlights that Mn2+ plays important roles in pathogen-plant interactions and that the yebN leader RNA can be a target candidate for anti-X. oryzae pv. oryzae drug development.


Assuntos
Regiões 5' não Traduzidas/genética , Interações Hospedeiro-Patógeno , Oryza/genética , Doenças das Plantas/microbiologia , Riboswitch/genética , Xanthomonas/genética , Regulação Bacteriana da Expressão Gênica , Compostos de Manganês/metabolismo , Modelos Biológicos , Oryza/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , RNA Bacteriano/química , RNA Bacteriano/genética , Sulfatos/metabolismo , Virulência , Xanthomonas/patogenicidade
15.
Br J Cancer ; 118(1): 38-42, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29149104

RESUMO

BACKGROUND: We evaluated the cumulative incidence rate (CIR) of central nervous system (CNS) and non-CNS progression in alectinib-treated patients with anaplastic lymphoma kinase (ALK)-positive non-small-cell lung cancer (NSCLC) to determine the extent to which alectinib may treat or control CNS disease. METHODS: Patients with crizotinib-pretreated locally advanced or metastatic disease received alectinib 600 mg orally twice daily in two phase II trials. All patients underwent baseline imaging and regular centrally reviewed scans. RESULTS: At 24 months, the CIR for CNS progression was lower in patients without vs with baseline CNS metastases (8.0 vs 43.9%). Patients with baseline CNS disease and prior radiotherapy had a higher CIR of CNS progression than radiotherapy-naive patients (50.5 vs 27.4%) and a lower CIR of non-CNS progression (25.8 vs 42.5%). Adverse events leading to withdrawal occurred in 5.9% and 6.7% of patients with and without baseline CNS metastases, respectively. CONCLUSIONS: This analysis indicates a potential role for alectinib in controlling and preventing CNS metastases.


Assuntos
Quinase do Linfoma Anaplásico/genética , Carbazóis/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Piperidinas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Administração Oral , Adulto , Idoso , Carbazóis/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias do Sistema Nervoso Central/epidemiologia , Neoplasias do Sistema Nervoso Central/secundário , Progressão da Doença , Feminino , Humanos , Incidência , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Piperidinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Resultado do Tratamento , Adulto Jovem
16.
J Cardiothorac Vasc Anesth ; 31(5): 1580-1587, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28780362

RESUMO

OBJECTIVES: Prolonged mechanical ventilation (PMV) after surgical repair of acute type-A aortic dissection (ATAAD) is associated with an increased risk for mortality and morbidity. The goal of this study was to evaluate the influence of PMV on early and late outcomes and to identify the risk factors for PMV after ATAAD repair. DESIGN, SETTING, AND PARTICIPANTS: This study was a retrospective analysis of prospectively collected data, which resulted from a prior clinical trial. Clinical outcomes were analyzed in 121 patients with ATAAD (mean age 46.6 ± 10.4; 93 men) who underwent total arch replacement combined with a frozen elephant trunk implantation at a mean of 3.6 days from onset. Multivariate analysis was used to identify risk factors for PMV after surgery. MEASUREMENTS AND MAIN RESULTS: The primary endpoint of this study was the occurrence of PMV after ATAAD surgery. The secondary end-points were risk factors for PMV, in-hospital mortality, and 1-year survival. Thirty-five (28.9%) patients required PMV. The PMV group demonstrated a longer ventilation time and length of intensive care unit stay (129 ± 79 h and 167 ± 119 h v 19 ± 10 h and 32 ± 23 h, respectively, p < 0.001). Postoperative mortality was 6.6% (8 of 121), including 6 (17.2%) in the PMV and 2 (2.3%) in the non-PMV groups (p = 0.003). PMV was associated with increased in-hospital mortality (odds ratio 6.4; 95% confidence interval 1.1-36.0; p = 0.036). Follow-up was complete in 88.6% (98 of 113) of patients at a mean of 26 months (1-39 mo). Survival at 1 year was significantly lower in the PMV group compared with the non-PMV group (77.1% v 95.3%, p = 0.002). Risk factors for PMV were the level of serum lactate (mmol/L) at the end of surgery (odds ratio 1.189; 95% confidence interval 1.026-1.377; p = 0.021) and a lower preoperative platelet count (109/L) (odds ratio 0.918; 95% confidence interval 0.847-0.994; p = 0.034). CONCLUSION: In this study, the occurrence of PMV was 28.9% in patients with ATAAD. A lower preoperative platelet count and a higher serum lactate level after ATAAD surgery were risk factors for PMV. Identification of risk factors may be helpful for preventing PMV and improving outcomes after surgical repair of ATAAD.


Assuntos
Dissecção Aórtica/mortalidade , Dissecção Aórtica/cirurgia , Respiração Artificial/tendências , Doença Aguda , Adulto , Dissecção Aórtica/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Respiração Artificial/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo
17.
Angew Chem Int Ed Engl ; 56(17): 4819-4823, 2017 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-28371093

RESUMO

Although chiral quaternary ammonium and phosphonium salts are commonly used for asymmetric organocatalysis, the catalytic ability of chiral tertiary sulfonium salts has yet to be demonstrated in asymmetric synthesis. Herein, we show that chiral bifunctional trialkylsulfonium salts catalyze highly enantioselective conjugate additions of 3-substituted oxindoles to maleimides under base-free neutral phase-transfer conditions.

18.
Eur J Orthod ; 37(6): 651-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25700989

RESUMO

OBJECTIVE: To identify and qualify the scientific evidence on the immediate and long-term effects of rapid maxillary expansion on the midpalatal suture in growing teenage or young adults, the related articles were selected. MATERIALS AND METHODS: Literatures were searched in the electronic databases, including Medline, Embase, Web of Science, and Cochrane Library. A methodologic-quality scoring (13-point) scale was used to evaluate the quality of the studies. RESULTS: Twelve relevant articles were identified. Midpalatal suture opening during orthodontic treatment with rapid maxillary expansion (RME) amounted to 12-52.5 percent of the total screw expansion. After the treatment of RME, the midpalatal suture seemed to be recalcificated, so the expansion of the midpalatal suture was stable, but there was no consistent evidence on whether the midpalatal sutural opening was parallel or triangular. LIMITATIONS: The methodologic quality of the included studies was assessed rigorously and many deficiencies were found. CONCLUSIONS: The majority of the articles were judged to be of low quality. Therefore, we could not draw any accurate conclusion on the basis of evidence in this systematic review.


Assuntos
Suturas Cranianas/anatomia & histologia , Técnica de Expansão Palatina , Palato/anatomia & histologia , Adolescente , Calcificação Fisiológica/fisiologia , Humanos , Maxila/anatomia & histologia , Adulto Jovem
19.
Environ Monit Assess ; 187(12): 729, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26545373

RESUMO

Fluoroquinolones (FQs) are a widely prescribed group of antibiotics. They enter the aqueous environment, where they are frequently detected, and can lead to a threat to human health. Drinking water treatment plants (DWTPs) play a key role in removing FQs from potable water. This study investigated the occurrence and removal of four selected FQs (norfloxacin (NOR), ciprofloxacin (CIP), enrofloxacin (ENR), and ofloxacin (OFL)) in three urban DWTPs in China. The treatment efficacy for each system was simultaneously evaluated. Two of the examined DWTPs used conventional treatment processes. The third used conventional processes followed by additional treatment processes (ozonation-biologically activated carbon (ozonation-BAC) and membrane technology). The average concentrations of the four FQs in the source water and the finished water ranged from 51 to 248 ng/L and from <5 to 46 ng/L, respectively. Based on residual concentrations, the conventional treatment system had a low removal of FQs. In contrast, the addition of advanced treatment processes such as the ozonation-BAC and membranes, substantially improved the removal of FQs. The finding of this study has important implications: even though coagulation-sedimentation and chlorination treatment processes can remove most target FQs, the typical practice of advanced treatment processes is necessary for the further removal.


Assuntos
Antibacterianos/análise , Água Potável/química , Fluoroquinolonas/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Anti-Infecciosos , China , Ciprofloxacina/análise , Enrofloxacina , Monitoramento Ambiental , Norfloxacino , Ofloxacino
20.
Zhong Yao Cai ; 38(5): 894-8, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26767280

RESUMO

OBJECTIVE: In order to apply the thesis basis for screening the Paris varieties which was suitable for the environments, the quality of Paris herbs of different varieties cultivated in different locations of Three Gorges Reservoir was evaluated based on the identification of active compositions. METHODS: The content of saponins in Paris herbs was measured by HPLC method; The total content of saponins, the total content of flavonoids and the total content of polysaccharides were evaluated using ultraviolet-visible spectrophotometry; Then the contents of active chemical compositions were used for comparison of the Paris herbs of different varieties in different locations. RESULTS: Types and the contents of saponin I, saponin II, saponin VI and saponin VII were all various in different Paris varieties located in different locations; with the analyses of the total content of saponins, the total content of flavonoids and the total content of polysaccharides, it was suggested that the chemical compositions existed obvious differences in different cultivars. CONCLUSION: It is proved that Paris polyphylla var. yunnanensis and Paris polyphylla var. chinensis could be cultivated on a large scale, but the techniques in artificial cultivation should be studied further. At the same time,Paris bashanensis and Paris polyphylla var. pseudothibetica are good cultivars for planting.


Assuntos
Liliaceae/química , Plantas Medicinais/química , Saponinas/química , Cromatografia Líquida de Alta Pressão , Meio Ambiente
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