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1.
Org Biomol Chem ; 22(14): 2819-2823, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38511315

RESUMEN

An efficient method was developed for the one-pot construction of C-B and C-I via visible light-induced transformation of nitroarenes. This protocol relies on the photochemical properties of nitroarenes under visible light, followed by reduction with B2pin2 and diazotization with tBuONO. An array of arylboronates and iodobenzenes were constructed smoothly after excitation with purple LEDs at room temperature. In addition, the synthetic utility of this method was further demonstrated in the late-stage modification of a drug molecule. The advantages of this strategy include metal-free system, mild reaction conditions and acceptable substrate scope.

2.
Mikrochim Acta ; 191(6): 326, 2024 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740583

RESUMEN

Migration is an initial step in tumor expansion and metastasis; suppressing cellular migration is beneficial to cancer therapy. Herein, we designed a novel biogated nanoagents that integrated the migration inhibitory factor into the mesoporous silica nanoparticle (MSN) drug delivery nanosystem to realize cell migratory inhibition and synergistic treatment. Antisense oligonucleotides (Anti) of microRNA-330-3p, which is positively related with cancer cell proliferation, migration, invasion, and angiogenesis, not only acted as the locker for blocking drugs but also acted as the inhibitory factor for suppressing migration via gene therapy. Synergistic with gene therapy, the biogated nanoagents (termed as MSNs-Gef-Anti) could achieve on-demand drug release based on the intracellular stimulus-recognition and effectively kill tumor cells. Experimental results synchronously demonstrated that the migration suppression ability of MSNs-Gef-Anti nanoagents (nearly 30%) significantly contributed to cancer therapy, and the lethality rate of the non-small-cell lung cancer was up to 70%. This strategy opens avenues for realizing efficacious cancer therapy and should provide an innovative way for pursuing the rational design of advanced nano-therapeutic platforms with the combination of cancer cell migratory inhibition.


Asunto(s)
Movimiento Celular , Quimioterapia Combinada , Nanopartículas , Neoplasias , Dióxido de Silicio , Movimiento Celular/efectos de los fármacos , Dióxido de Silicio/química , Quimioterapia Combinada/métodos , Neoplasias/tratamiento farmacológico , Sistema de Administración de Fármacos con Nanopartículas/química , Sistema de Administración de Fármacos con Nanopartículas/uso terapéutico , Nanopartículas/química , Nanopartículas/uso terapéutico , Nanopartículas/ultraestructura , Células A549 , Microscopía Electrónica de Transmisión , Humanos
3.
Mikrochim Acta ; 191(3): 127, 2024 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-38334844

RESUMEN

A one-target-many-trigger signal model sensing strategy is proposed for quickly, sensitive and on-site detection of the environmental pollutant p-aminophenol (PAP) by use of a commercial personal glucose meter (PGM) for signal readout with the core-shell "loading-type" nanomaterial MSNs@MnO2 as amplifiable nanoprobes. In this design, the mesoporous silica nanoparticles (MSNs) nanocontainer with entrapped signal molecule glucose is coated with redoxable manganese dioxide (MnO2) nanosheets to form the amplifiable nanoprobes (Glu-MSNs@MnO2). When encountered with PAP, the redox reaction between the MnO2 and PAP can induce the degradation of the outer layer of MSNs@MnO2, liberating multiple copies of the loaded glucose to light up the PGM signal. Owing to the high loading capability of nanocarriers, a "one-to-many" relationship exists between the target and the signal molecule glucose, which can generate adequate signal outputs to achieve the requirement of on-site determination of environmental pollutants. Taking advantage of this amplification mode, the developed PAP assay owns a dynamic linear range of 10.0-400 µM with a detection limit of 2.78 µM and provides good practical application performance with above 96.7 ± 4.83% recovery in environmental water and soil samples. Therefore, the PGM-based amplifiable sensor for PAP proposed can accommodate these requirements of environment monitoring and has promising potential for evaluating pollutants in real environmental samples.


Asunto(s)
Aminofenoles , Nanoestructuras , Óxidos , Compuestos de Manganeso , Glucosa , Dióxido de Silicio
4.
Angew Chem Int Ed Engl ; : e202407193, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744679

RESUMEN

As a leading contender to replace lead halide perovskites, tin-based perovskites have demonstrated ever increasing performance in solar cells and light-emitting diodes (LEDs). They tend to be processed with dimethyl sulfoxide (DMSO) solvent, which has been identified as a major contributor to the Sn(II) oxidation during film fabrication, posing a challenge to the further improvement of Sn-based perovskites. Herein, we use NMR spectroscopy to investigate the kinetics of the oxidation of SnI2, revealing that autoamplification takes place, accelerating the oxidation as the reaction progresses. We propose a mechanism consistent with these observations involving water participation and HI generation. Building upon these insights, we have developed low-temperature Sn-based perovskite LEDs (PeLEDs) processed at 60 °C, achieving enhanced external quantum efficiencies (EQEs). Our research underscores the substantial potential of low-temperature DMSO solvent processes and DMSO-free solvent systems for fabricating oxidation-free Sn-based perovskites, shaping the future direction in processing Sn-containing perovskite materials and optoelectronic devices.

5.
Int J Neuropsychopharmacol ; 26(10): 655-668, 2023 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-37025079

RESUMEN

BACKGROUND: Although thought of as a multimodal-acting antidepressant targeting the serotonin system, more molecules are being shown to participate in the antidepressant mechanism of vortioxetine. A previous report has shown that vortioxetine administration enhanced the expression of rapamycin complex 1 (mTORC1) in neurons. It has been well demonstrated that mTORC1 participates in not only the pathogenesis of depression but also the pharmacological mechanisms of many antidepressants. Therefore, we speculate that the antidepressant mechanism of vortioxetine may require mTORC1. METHODS: Two mouse models of depression (chronic social defeat stress and chronic unpredictable mild stress) and western blotting were first used together to examine whether vortioxetine administration produced reversal effects against the chronic stress-induced downregulation in the whole mTORC1 signaling cascade in both the hippocampus and medial prefrontal cortex (mPFC). Then, LY294002, U0126, and rapamycin were used together to explore whether the antidepressant effects of vortioxetine in mouse models of depression were attenuated by pharmacological blockade of the mTORC1 system. Furthermore, lentiviral-mTORC1-short hairpin RNA-enhanced green fluorescence protein (LV-mTORC1-shRNA-EGFP) was adopted to examine if genetic blockade of mTORC1 also abolished the antidepressant actions of vortioxetine in mice. RESULTS: Vortioxetine administration produced significant reversal effects against the chronic stress-induced downregulation in the whole mTORC1 signaling cascade in both the hippocampus and mPFC. Both pharmacological and genetic blockade of the mTORC1 system notably attenuated the antidepressant effects of vortioxetine in mice. CONCLUSIONS: Activation of the mTORC1 system in the hippocampus and mPFC is required for the antidepressant actions of vortioxetine in mice.


Asunto(s)
Antidepresivos , Hipocampo , Ratones , Animales , Vortioxetina/farmacología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Antidepresivos/farmacología , Antidepresivos/metabolismo , Corteza Prefrontal/metabolismo , Sirolimus/farmacología
6.
Int J Neuropsychopharmacol ; 26(10): 680-691, 2023 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-37603290

RESUMEN

BACKGROUND: Although depression has been a serious neuropsychiatric disorder worldwide, current antidepressants used in clinical practice have various weaknesses, including delayed onset and low rates of efficacy. Recently, the development of new antidepressants from natural herbal medicine has become one of the important research hotspots. Cucurbitacin B is a natural compound widely distributed in the Cucurbitaceae and Cruciferae families and has many pharmacological activities. The present study aimed to investigate whether cucurbitacin B possess antidepressant-like effects in mice. METHODS: The antidepressant-like effects of cucurbitacin B on mice behaviors were explored using the forced swim test, tail suspension test, open field test, sucrose preference test, and a chronic unpredictable mild stress model of depression together. Then, western blotting and immunofluorescence were used to examine the effects of cucurbitacin B on the brain-derived neurotrophic factor (BDNF)-tyrosine kinase B (TrkB) signaling cascade and neurogenesis in the hippocampus of mice. Furthermore, BDNF-short hairpin RNA, K252a, and p-chlorophenylalanine methyl ester were adopted together to determine the antidepressant mechanism of cucurbitacin B. RESULTS: It was found that administration of cucurbitacin B indeed produced notable antidepressant-like effects in mice, which were accompanied with significant promotion in both the hippocampal BDNF-TrkB pathway and neurogenesis. The antidepressant mechanism of cucurbitacin B involves the hippocampal BDNF-TrkB system but not the serotonin system. CONCLUSIONS: Cucurbitacin B has the potential to be a novel antidepressant candidate.


Asunto(s)
Antidepresivos , Factor Neurotrófico Derivado del Encéfalo , Depresión , Animales , Humanos , Ratones , Antidepresivos/farmacología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Depresión/tratamiento farmacológico , Depresión/metabolismo , Modelos Animales de Enfermedad , Hipocampo , Estrés Psicológico/tratamiento farmacológico , Estrés Psicológico/metabolismo
7.
Mol Psychiatry ; 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36434056

RESUMEN

Elucidating the molecular mechanism underlying the hyperactivity of the hypothalamic-pituitary-adrenal axis during chronic stress is critical for understanding depression and treating depression. The secretion of corticotropin-releasing hormone (CRH) from neurons in the paraventricular nucleus (PVN) of the hypothalamus is controlled by salt-inducible kinases (SIKs) and CREB-regulated transcription co-activators (CRTCs). We hypothesised that the SIK-CRTC system in the PVN might contribute to the pathogenesis of depression. Thus, the present study employed chronic social defeat stress (CSDS) and chronic unpredictable mild stress (CUMS) models of depression, various behavioural tests, virus-mediated gene transfer, enzyme-linked immunosorbent assay, western blotting, co-immunoprecipitation, quantitative real-time reverse transcription polymerase chain reaction, and immunofluorescence to investigate this connection. Our results revealed that both CSDS and CUMS induced significant changes in SIK1-CRTC1 signalling in PVN neurons. Both genetic knockdown of SIK1 and genetic overexpression of CRTC1 in the PVN simulated chronic stress, producing a depression-like phenotype in naive mice, and the CRTC1-CREB-CRH pathway mediates the pro-depressant actions induced by SIK1 knockdown in the PVN. In contrast, both genetic overexpression of SIK1 and genetic knockdown of CRTC1 in the PVN protected against CSDS and CUMS, leading to antidepressant-like effects in mice. Moreover, stereotactic infusion of TAT-SIK1 into the PVN also produced beneficial effects against chronic stress. Furthermore, the SIK1-CRTC1 system in the PVN played a role in the antidepressant actions of fluoxetine, paroxetine, venlafaxine, and duloxetine. Collectively, SIK1 and CRTC1 in PVN neurons are closely involved in depression neurobiology, and they could be viable targets for novel antidepressants.

8.
Mikrochim Acta ; 190(3): 99, 2023 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-36809414

RESUMEN

A versatile DNA nanomachine detection system has been developed via the combination of DNAzyme with catalytic hairpin assembly (CHA) technology for achieving accurate and sensitive detection of lead ions (Pb2+). In the presence of target Pb2+, capture DNA nanomachine formed by AuNP and DNAzyme recognized and reacted with Pb2+, which yielded an "active" DNAzyme, that induced the cleavage of substrate strand, and then released the initiator DNA (TT) for CHA. With the help of the initiator DNA TT, self-powered CHA was activated to achieve the signal amplification reaction in the detection of DNA nanomachine. Meanwhile, the initiator DNA TT was released and hybridized with the other H1 strand to initiate another CHA, replacement, and turnovers, producing enhanced fluorescence signal of fluorophore FAM (excitation 490 nm/emission 520 nm) for sensitive determination of Pb2+. Under the optimized conditions, the DNA nanomachine detection system revealed high selectivity toward Pb2+ in the concentration range 50-600 pM, with the limit of detection (LOD) of 31 pM. Recovery tests demonstrated that the DNA nanomachine detection system has excellent detection capability in real samples. Therefore, the proposed strategy can be extended and act as a basic platform for highly accurate and sensitive detection of various heavy metal ions.


Asunto(s)
Técnicas Biosensibles , ADN Catalítico , Plomo , ADN , Iones
9.
Expert Syst Appl ; 213: 118841, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36157791

RESUMEN

The outbreak of COVID-19 brings almost the biggest explosions of scientific literature ever. Facing such volume literature, it is hard for researches to find desired citation when carrying out COVID-19 related research, especially for junior researchers. This paper presents a novel neural network based method, called citation relational BERT with heterogeneous deep graph convolutional network (CRB-HDGCN), for COVID-19 inline citation recommendation task. The CRB-HDGCN contains two main stages. The first stage is to enhance the representation learning of BERT model for COVID-19 inline citation recommendation task through CRB. To achieve the above goal, an augmented citation sentence corpus, which replaces the citation placeholder with the title of the cited papers, is used to lightly retrain BERT model. In addition, we extract three types of sentence pair according citation relation, and establish sentence prediction tasks to further fine-tune the BERT model. The second stage is to learn effective dense vector of nodes among COVID-19 bibliographic graph through HDGCN. The HDGCN contains four layers which are essentially all sub neural networks. The first layer is initial embedding layer which generates initial input vectors with fixed size through CRB and a multilayer perceptron. The second layer is a heterogeneous graph convolutional layer. In this layer, we expand traditional homogeneous graph convolutional network into heterogeneous by subtly adding heterogeneous nodes and relations. The third layer is a deep attention layer. This layer uses trainable project vectors to reweight the node importance simultaneously according to both node types and convolution layers, which further promotes the performance of learnt node vectors. The last decoder layer recovers the graph structure and let the whole network trainable. The recommendation is finally achieved by integrating the high performance heterogeneous vectors learnt from CRB-HDGCN with the query vectors. We conduct experiments on the CORD-19 and LitCovid datasets. The results show that compared with the second best method CO-Search, CRB-HDGCN improves MAP, MRR, P@100 and R@100 with 21.8%, 22.7%, 37.6% and 21.2% on CORD-19, and 29.1%, 25.9%, 15.3% and 11.3% on LitCovid, respectively.

10.
BMC Public Health ; 22(1): 810, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35459156

RESUMEN

BACKGROUNDS: Many literature reviews summarized relationships between screen time and child health, but they only included a few studies conducted in Chinese children and adolescents. The potential influence of screen time may vary by social context. The current systematic review and meta-analysis aimed to evaluate relationships between screen time and health issues among Chinese school-aged children and adolescents. METHODS: Peer-reviewed articles written in Chinese and English were retrieved from CNKI, Wanfang, PubMed, Embase, and Web of Science from inception to June 2020. The Downs & Black checklist was applied to assess study quality. Meta analyses used random effect models and mixed effects model to calculate pooled adjusted odds ratios and 95% confidence intervals. Heterogeneity, sensitivity, and publication bias were assessed using Q and I2 statistics, "one-study removed" analysis, the funnel plot, trim and fill analysis, and classical fail-safe N, respectively. RESULTS: In total, we identified 252 articles reporting 268 studies with unique samples. These studies investigated relationships between screen time and health issues of adiposity, myopia, psycho-behavioral problems, poor academic performance, cardiometabolic disease risks, sleep disorder, poor physical fitness, musculoskeletal injury, sub-health, and miscellaneous issues of height and pubertal growth, injury, sick leave, and respiratory symptoms. Proportions of studies reporting positive relationships with screen time were lowest in adiposity (50.6%) and higher in myopia (59.2%) and psycho-behavioral problems (81.8%). Other health issues were examined in 10 or less studies, all of which had more than half showing positive relationships. The pooled odds ratio from 19 studies comparing health risks with the screen time cutoff of 2 hours per day was 1.40 (95% CI: 1.31 to 1.50, I2 = 85.9%). The pooled effect size was 1.29 (95% CI: 1.20 to 1.39) after trimming 7 studies for publication bias adjustments. CONCLUSIONS: Findings exclusively generated from Chinese school-aged children and adolescents resonate those mainly from western countries. Evidence suggests that higher levels of screen time are related with greater risks of various health issues, although the relationships appear to be weak and intertwined with other confounding factors. Future studies need to investigate health-specific dose effects and mechanisms of screen time.


Asunto(s)
Miopía , Tiempo de Pantalla , Adolescente , Niño , China/epidemiología , Humanos , Aptitud Física
11.
Bioprocess Biosyst Eng ; 45(7): 1137-1147, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35624323

RESUMEN

Solid-phase microbial fuel cell (SMFC) can accelerate the removal of organic pollutants through the electrons transfer between microorganisms and anodes in the process of generating electricity. Thus, the characteristics of the anode material will affect the performance of SMFCs. In this study, corn stem (CS) is first calcined into a 3D macroporous electrode, and then modified with carbon nanotubes (CNTs) through electrochemical deposition method. Scanning electron microscope analysis showed the CS/CNT anode could increase the contact area on the surface. Furthermore, electrochemical impedance spectroscopy and cyclic voltammetry analysis indicated the electrochemical double-layer capacitance of the CS/CNT anode increased while its internal resistance decreased significantly. These characteristics are crucial for increasing bacterial adhesion capability and electron transfer rate. The maximum output voltage of the SMFC with CS/CNT anode was 158.42 mV, and the removal rate of petroleum hydrocarbon (PH) reached 42.17%, 2.72 times that of unmodified CS. In conclusion, CNT-modified CS is conducive to improve electron transfer rate and microbial attachment, enhancing the removal efficiency of PH in soil.


Asunto(s)
Fuentes de Energía Bioeléctrica , Nanotubos de Carbono , Petróleo , Fuentes de Energía Bioeléctrica/microbiología , Electrodos , Hidrocarburos , Nanotubos de Carbono/química , Suelo , Zea mays
12.
J Org Chem ; 86(23): 17244-17248, 2021 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-34807586

RESUMEN

The development of a novel environmental benign and sustainable synthetic method for highly efficient construction and direct C-H functionalization of N-heterocycles remains a pivotal central research topic for organic and medicinal chemistry. Herein, a novel visible-light-enabled biomimetic aza-6π electrocyclization for efficient assembly of diverse pyridines and further tandem Minisci-type reaction were developed. A broad spectrum of polysubstituted picolinaldehydes were readily constructed with high efficacy and good functional group tolerance under metal- and oxidant-free conditions.


Asunto(s)
Luz , Piridinas , Catálisis , Metales
13.
Sensors (Basel) ; 21(2)2021 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-33477895

RESUMEN

This paper addresses the problem of evaluating vehicle failure modes efficiently during the driving process. Generally, the most critical factors for preventing risk in potential failure modes are identified by the experience of experts through the widely used failure mode and effect analysis (FMEA). However, it has previously been difficult to evaluate the vehicle failure mode with crisp values. In this paper, we propose a novel hybrid scheme based on a cost-based FMEA, fuzzy analytic hierarchy process (FAHP), and extended fuzzy multi-objective optimization by ratio analysis plus full multiplicative form (EFMULTIMOORA) to evaluate vehicle failure modes efficiently. Specifically, vehicle failure modes are first screened out by cost-based FMEA according to maintenance information, and then the weights of the three criteria of maintenance time (T), maintenance cost (C), and maintenance benefit (B) are calculated using FAHP and the rankings of failure modes are determined by EFMULTIMOORA. Different from existing schemes, the EFMULTIMOORA in our proposed hybrid scheme calculates the ranking of vehicle failure modes based on three new risk factors (T, C, and B) through fuzzy linguistic terms for order preference. Furthermore, the applicability of the proposed hybrid scheme is presented by conducting a case study involving vehicle failure modes of one common vehicle type (Hyundai), and a sensitivity analysis and comparisons are conducted to validate the effectiveness of the obtained results. In summary, our numerical analyses indicate that the proposed method can effectively help enterprises and researchers in the risk evaluation and the identification of critical vehicle failure modes.

14.
Blood Press ; 29(1): 3-12, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31718311

RESUMEN

Purposes: Many studies have indicated that orthostatic hypotension (OH) may be a risk factor for dementia and stroke, but the results have been inconsistent. To further ascertain the links between OH and cognition or stroke, a meta-analysis was performed.Methods: The Chinese Biomedical Database, PubMed, Web of Science, and the Cochrane Library database were searched (up to March 2019) to identify prospective cohort studies that examined the associations between OH and the risks of stroke and dementia among adult populations. Subgroup analyses and meta-regression analyses were conducted to identify sources of heterogeneity. We also performed Begg's test and Egger's test to assess publication bias.Results: A total of 3490 articles were identified, and 18 prospective observational cohort studies were ultimately included. Among these studies, eight prospective studies were about stroke, nine studies were about cognition and one study reported data about both stroke and dementia. Meta-analysis revealed an association between OH and worse cognition (hazard ratio (HR): 1.18, 95% confidence interval (CI): 1.03-1.35, I2 = 69.5%). For dementia, the pooled HR was 1.30, with 95% CI: 1.14-1.48, I2 = 31.0%. In addition, we found that OH was associated with a higher risk of stroke (HR: 1.36, 95% CI = 1.17-1.57, I2 = 67.3%). No publication bias was detected.Conclusion: This meta-analysis provides evidence that OH was associated with worse cognition. OH accounted for a 30% increase in the risk of dementia and a 36% increase in the risk of stroke.


Asunto(s)
Demencia/etiología , Hipotensión Ortostática/complicaciones , Accidente Cerebrovascular/etiología , Adulto , Cognición , Estudios de Cohortes , Bases de Datos como Asunto , Humanos , Estudios Prospectivos
15.
Bioprocess Biosyst Eng ; 43(3): 383, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31820097

RESUMEN

It has been brought to our attention that in our article, explanations about cable bacteria are not rigorous. We apologize for these and note the specific reporting issues and errors below, with their corrections.

16.
Bioprocess Biosyst Eng ; 43(3): 373-381, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31659438

RESUMEN

In this paper, a graphene/Fe2O3 (G/Fe2O3) modified anode was prepared through a simple one-step hydrothermal reduction method to improve the performance of microbial fuel cell (MFC). The power density of MFC with the G/Fe2O3 anode was 334 ± 4 mW/m2, which was 1.72 times and 2.59 times that of MFC with a graphene anode and an unmodified anode, respectively. Scanning electron microscopy and iron reduction rate experiment showed that G/Fe2O3 materials had good biocompatibility. Furthermore, microbial community analysis results indicated that the predominant populations on the anode biofilm belonged to Enterobacteriaceae, and the abundance of Desulfovibrio increased in the presence of the Fe2O3. Thus, the combination of graphene and Fe2O3 provided high electrical conductivity to facilitate extracellular electron transfer (EET) and improved biocompatibility to promote the exoelectrogenic bacteria formation. Therefore, G/Fe2O3 is an effective anode material for enhancing the performance of MFCs.


Asunto(s)
Fuentes de Energía Bioeléctrica , Carbono/química , Electrodos , Compuestos Férricos/química , Grafito/química , Biopelículas , Cristalografía por Rayos X , Desulfovibrio/metabolismo , Enterobacteriaceae/metabolismo , Hierro/química , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión
17.
Opt Express ; 27(16): 22890-22897, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31510573

RESUMEN

The phenomenon of vortex beams passing through a diffraction plate with rotationally symmetric superposition of spiral pinholes array is investigated. The variations of the topological charges of vortex beams are theoretically analyzed, numerically simulated and experimentally observed. It proves that the obtained topological charge value (l) is a combination of that of incident beam (l0) and the number of the spiral structures (m). The relationship is l = Mm-l0, where M is an integer. With this study, we proved that spiral transmission structures can also achieve the variations of the topological charge of a vortex beam. And this method is simple and costless. With the advantages of this method, it might have important applications in optical communications and optical tweezers.

18.
Environ Health ; 18(1): 98, 2019 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-31771610

RESUMEN

BACKGROUND: Very few studies have focused on the relationship between ambient apparent temperature (AT) and admission of mental and behaviour disorders (MDs). Therefore, a time-series study was conducted in Yancheng, China, to explore the effects of AT on the daily emergency admissions of patients with MDs over the period of 2014-17. METHODS: A quasi-Poisson generalized linear model (GLM) combined with a distributed lag non-linear model (DLNM) was adopted to explore the associations after adjusting for time trend, day of the week, humidity, sunshine duration, rainfall, holidays and air pollutants. In the subgroup analysis, the modification effects of age and sex were also examined. RESULTS: Overall, 8438 cases of MDs emergency admissions were identified. With the apparent temperature with the minimum number of admissions (- 3.4 °C) serving as a reference, a positive correlation emerged between high AT and daily emergency admissions of patients with MDs in Yancheng, China, with the lagged effect of 1 to 5 days. The subgroup analysis demonstrated a positive relationship between AT and MDs emergency admissions among males and individuals younger than 45 years old, with no lagged effect. CONCLUSIONS: The results will provide important scientific evidence for mental health policy-makers and practitioners for possible intervention, especially among the vulnerable populations.


Asunto(s)
Hospitalización/estadística & datos numéricos , Calor/efectos adversos , Trastornos Mentales/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , China/epidemiología , Ciudades , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Factores de Tiempo , Adulto Joven
19.
Molecules ; 24(4)2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30769949

RESUMEN

Clerodane diterpenoids are the main bioactive constituents of Croton crassifolius and are proved to have multiple biological activities. However, quality control (QC) research on the constituents are rare. Thus, the major research purpose of the current study was to establish an efficient homogenate extraction (HGE) process combined with a sensitive and specific ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC⁻MS) technique together for the rapid extraction and determination of clerodane diterpenoids in C. crassifolius. All calibration curves showed good linearity (r > 0.9943) within the test ranges and the intra- and inter-day precisions and repeatability were all within required limits. This modified HGE⁻UHPLC⁻MS method only took 5 min to extract nine clerodane diterpenoids in C. crassifolius and another 12 min to quantify these components. The results indicated that the quantitative analysis based on UHPLC⁻MS was a feasible method for QC of clerodane diterpenoids in C. crassifolius, and the findings outlined in the current study also inferred the potential of the method in the QC of clerodane diterpenoids in other complex species of plants.


Asunto(s)
Cromatografía Líquida de Alta Presión , Croton/química , Diterpenos/química , Espectrometría de Masas , Extractos Vegetales/química , Fraccionamiento Químico , Diterpenos/análisis , Diterpenos/farmacología , Estructura Molecular , Extractos Vegetales/análisis , Extractos Vegetales/farmacología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
J Nanosci Nanotechnol ; 18(8): 5770-5776, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29458638

RESUMEN

In this paper, we developed an environmental friendly, cost effective, simple and green approach to reduce graphene oxide (GO) by a sulfate-reducing bacterium Desulfovibrio desulfuricans. The D. desulfuricans reduces exfoliated GO to reduced graphene oxide (rGO) at 25 °C in an aqueous solution without any toxic and environmentally harmful reducing agents. The rGO was characterized with X-ray Diffraction, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Transmission Electron Microscope, X-ray Photoelectron Spectroscopy and Raman Spectroscopy. The analysis results showed that rGO had excellent properties and multi-layer graphene sheets structure. Furthermore, we demonstrated that D. desulfuricans, one of the primary bacteria responsible for the biocorrosion of various metals, might reduce GO to rGO on the surface of copper and prevented the corrosion of copper, which confirmed that electrophoretic deposition of GO on the surface of metals had great potential on the anti-biocorrosion applications.

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