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1.
Cell Mol Biol (Noisy-le-grand) ; 69(8): 209-213, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37715382

RESUMO

Diabetic nephropathy (DN) is considered to be a kidney disease caused by diabetes. In recent years, the incidence of DN has been on the rise, which is also a major challenge in the treatment and prognosis of the disease. Therefore, the search for new biomarkers of DN is urgent and has important clinical significance for reducing the morbidity and mortality of DN. In this study, two datasets GSE1009 and GSE142153 were selected to extract expression profile-based data from DN glomerular samples, and 238 differentially expressed genes (DEGs) were screened. Then, through enrichment analysis, the biological function of DEGs involved in DN disease was preliminarily explored. Subsequently, the STRING website was used to construct a protein-protein interaction map (PPI) to find 10 key genes (CHEK1, ITGB3, COL4A2, COL4A5, COL4A3, COL4A4, CCNB2, CCNB1, TPX2, KIF11), Which play an important role in the progression of DN disease and are closely related to other genes. CHEK1 was the focus of this study, and the expression level of CHEK1 in glomerular epithelial cell models was verified by qRT-PCR. Our results suggest that CHEK1 is a potential biomarker of the degree of damage to DN glomerular epithelial cells.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Humanos , Nefropatias Diabéticas/genética , Relevância Clínica , Biologia Computacional , Células Epiteliais , Quinase 1 do Ponto de Checagem/genética
2.
Compr Rev Food Sci Food Saf ; 22(4): 3105-3129, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37199492

RESUMO

Food preservation is a critical issue in ensuring food safety and quality. Growing concern around industrial pollution of food and demand for environmentally sustainable food has led to increased interest in developing effective and eco-friendly preservation techniques. Gaseous ClO2 has gained attention for its strong oxidizing properties, high efficacy in microorganism inactivation, and potential for preserving the attributes and nutritional quality of fresh food while avoiding the formation of toxic byproducts or unacceptable levels of residues. However, the widespread use of gaseous ClO2 in the food industry is limited by several challenges. These include large-scale generation, high cost and environmental considerations, a lack of understanding of its mechanism of action, and the need for mathematical models to predict inactivation kinetics. This review aims to provide an overview of the up-to-date research and application of gaseous ClO2 . It covers preparation methods, preservation mechanisms, and kinetic models that predict the sterilizing efficacy of gaseous ClO2 under different conditions. The impacts of gaseous ClO2 on the quality attributes of fresh produce and low-moisture foods, such as seeds, sprouts, and spices, are also summarized. Overall, gaseous ClO2 is a promising preservation approach, and future studies are needed to address the challenges in large-scale generation and environmental considerations and to develop standardized protocols and databases for safe and effective use in the food industry.


Assuntos
Desinfetantes , Gases , Gases/farmacologia , Contagem de Colônia Microbiana , Desinfetantes/química , Cinética , Conservação de Alimentos/métodos , Sementes
3.
Opt Lett ; 47(14): 3616-3619, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35838744

RESUMO

Nanowires (NWs) are essential building blocks of photonic devices for guiding light waves. However, the controlled synthesis of non-circular NWs remains challenging. Herein, we develop a bottom-up approach for the fabrication of high-quality elliptical gold NWs with finely tuned geometry engineering by using an advanced ion-track template technology. Compared to ordinary NWs, the rotational symmetry breaking leads to highly polarization-dependent plasmonic responses. Modal analysis shows that the lowest dipolar HE1 mode splits into two branches where the attenuation of the long-range branch decreases by 40%, while the short-range branch has a stronger enhanced near-field. Novel, to the best of our knowledge, plasmonic Fabry-Pérot resonances on finite NWs are measured. Our method can be extended to fabricate non-circular NWs with other materials, holding potential for novel applications from quantum to collective scales.

4.
Environ Res ; 209: 112732, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35077715

RESUMO

Decomposing cyanobacterial bloom-induced black blooms been seen as an issue in the management of freshwater ecosystems, but its effect on sulfate-reducing bacteria (SRB) in shallow freshwater lakes is not clear. The objective of this study is to present an in-depth investigation of black bloom effects on the activities and composition of SRB, as well as the interactions between SRB and other bacteria. Water and surface sediments samples were collected from a shallow freshwater lake during black and non-black blooms. Sulfate reduction rates (SRRs) in the water column were determined from the linear regression of sulfate depletion with time. Quantitative real-time polymerase chain reactions (qPCRs), targeting the dsrA gene and Illumina sequencing of 16S rDNA, were used to estimate the SRB population and SRB community structures, respectively. Our data indicate that although a higher abundance of SRB was responsible for the higher SRR in the bottom water (34.09 ±â€¯2.37 nmol mL-1 day-1) than in the surface water (14.57 ±â€¯2.91 nmol mL-1 day-1) during black blooms, cell-specific sulfate reduction rates (csSRRs) in the distinct water layers were not significantly different (P = 0.95), with the value of approximately 0.017 fmol cell-1 day-1. Additionally, Desulfomicrobium and Desulfovibrio were the two main genera of SRB in the water column during black bloom season, while Desulfobulbus, Desulfobacca and Desulfatiglans genera were identified in the sediments of both the black and non-black blooms in genera pools. Each SRB genus preferentially associated with bacteria for specific functions in the bacterial co-occurrence network, regardless of whether black booms occurred or not. These results extend our knowledge on the importance of SRB during black blooms and the adaptation of SRB to environmental changes in freshwater lakes.


Assuntos
Cianobactérias , Lagos , Ecossistema , Eutrofização , Lagos/química , Sulfatos
5.
J Nanobiotechnology ; 20(1): 514, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463277

RESUMO

BACKGROUND: The prevalence of viral infectious diseases has become a serious threat to public safety, economic and social development. Vaccines have been served as the most effective platform to prevent virus transmission via the activation of host immune responses, while the low immunogenicity or safety, the high cost of production, storage, transport limit their effective clinical application. Therefore, there is a need to develop a promising strategy to improve the immunogenicity and safety of vaccines. METHODS: We developed a splenic-targeting biomimetic nanovaccine (NV) that can boost protective humoral and cellular immunity against african swine fever virus (ASFV) infection. The universal PLGA nanoparticles (CMR-PLGA/p54 NPs) coated with mannose and CpG (TLR9 agonist) co-modified red blood cell (RBC) membrane were prepared, which comprised a viral antigen (p54) and can be served as a versatile nanovaccine for elevating protective immunity. RESULTS: CMR-PLGA/p54 NVs could be effectively uptaken by BMDC and promoted BMDC maturation in vitro. After subcutaneous immunization, antigen could be effectively delivered to the splenic dendritic cells (DCs) due to the splenic homing ability of RBC and DC targeting capacity of mannose, which promoted antigen presentation and DCs maturation, and further elicited higher levels of cytokines secretion and specific IgG titers, CD4+ and CD8+ T cells activation and B maturation. Moreover, NVs demonstrated notable safety during the immunization period. CONCLUSIONS: This study demonstrates the high potential of CMR-PLGA NPs as vaccine delivery carriers to promote humoral and cellular immune responses, and it provides a promising strategy to develop safe and effective vaccines against viral infectious diseases.


Assuntos
Vírus da Febre Suína Africana , Viroses , Animais , Suínos , Biomimética , Manose , Linfócitos T CD8-Positivos
6.
Atmos Environ (1994) ; 2762022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35814352

RESUMO

A number of studies have found differing associations of disease outcomes with PM2.5 components (or species) and sources (e.g., biomass burning, diesel vehicles and gasoline vehicles). Here, a unique method of fusing daily chemical transport model (Community Multiscale Air Quality Modeling) results with observations has been utilized to generate spatiotemporal fields of the concentrations of major gaseous pollutants (CO, NO2, NOx, O3, and SO2), total PM2.5 mass, and speciated PM2.5 (including crustal elements) over North Carolina for 2002-2010. The fused results are then used in chemical mass balance source apportionment model, CMBGC-Iteration, which uses both gas constraint and particulate matter concentrations to quantify source impacts. The method, as applied to North Carolina, quantifies the impacts of ten source categories and provides estimates of source contributions to PM2.5 concentrations. The ten source categories include both primary sources (diesel vehicles, gasoline vehicles, dust, biomass burning, coal-fired power plants and sea salt) and secondary components (ammonium sulfate, ammonium bisulfate, ammonium nitrate and secondary organic carbon). The results show a steady decrease in anthropogenic source impacts, especially from diesel vehicles and coal-fired power plants. Secondary pollutant components accounted for approximately 70% of PM2.5 mass. This study demonstrates an ability to provide spatiotemporal fields of both PM components and source impacts using a chemical transport model fused with observation data, linked to a receptor-based source apportionment method, to develop spatiotemporal fields of multiple pollutants.

7.
BMC Musculoskelet Disord ; 23(1): 254, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292004

RESUMO

BACKGROUND: This study was aimed to develop a novel dynamic measurement technique for testing the material properties and investigating the effect of continuous compression load on the structural and mechanical properties of human heel pad during actual gait. METHODS: The dual fluoroscopic imaging system (DFIS) and dynamic foot-ground contact pressure-test plate were used for measuring the material properties, including primary thickness, peak strain, peak stress, elastic modulus, viscous modulus and energy dissipation rate (EDR), both at time zero and following continuous loading. Ten healthy pilot subjects, aged from 23 to 72 (average: 46.5 ± 17.6), were enrolled. A "three-step gait cycle" is performed for all subjects, with the second step striking at a marked position on the force plate with the heel to maintain the location of the tested foot to be in the view of fluoroscopes. The subjects were measured at both relaxed (time-zero group) and fatigue (continuous-loading group) statuses, and the left and right heels were measured using the identical procedures. RESULTS: The peak strain, peak stress, elastic modulus, and EDR are similar before and after continuous load, while the viscous modulus was significantly decreased (median: 43.9 vs. 20.37 kPa•s; p < 0.001) as well as primary thicknesses (median: 15.99 vs. 15.72 mm; p < 0.001). Age is demonstrated to be moderately correlated with the primary thicknesses both at time zero (R = -0.507) and following continuous load (R = -0.607). The peak stress was significantly correlated with the elastic modulus before (R = 0.741) and after continuous load (R = 0.802). The peak strain was correlated with the elastic modulus before (R = -0.765) and after continuous load (R = -0.801). The correlations between the viscous modulus and peak stress/ peak strain are similar to above(R = 0.643, 0.577, - 0.586 and - 0.717 respectively). The viscous modulus is positively correlated with the elastic modulus before (R = 0.821) and after continuous load (R = 0.784). CONCLUSIONS: By using dynamic fluoroscopy combined with the plantar pressure plate, the in vivo viscoelastic properties and other data of the heel pad in the actual gait can be obtained. Age was negatively correlated with the primary thickness of heel pad and peak strain, and was positively correlated with viscous modulus. Repetitive loading could decrease the primary thickness of heel pad and viscous modulus.


Assuntos
Marcha , Calcanhar , Idoso , Fenômenos Biomecânicos , , Calcanhar/diagnóstico por imagem , Humanos , Projetos Piloto
8.
J Med Internet Res ; 24(11): e40361, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36427233

RESUMO

BACKGROUND: Electronic medical records (EMRs) of patients with lung cancer (LC) capture a variety of health factors. Understanding the distribution of these factors will help identify key factors for risk prediction in preventive screening for LC. OBJECTIVE: We aimed to generate an integrated biomedical graph from EMR data and Unified Medical Language System (UMLS) ontology for LC, and to generate an LC health factor distribution from a hospital EMR of approximately 1 million patients. METHODS: The data were collected from 2 sets of 1397 patients with and those without LC. A patient-centered health factor graph was plotted with 108,000 standardized data, and a graph database was generated to integrate the graphs of patient health factors and the UMLS ontology. With the patient graph, we calculated the connection delta ratio (CDR) for each of the health factors to measure the relative strength of the factor's relationship to LC. RESULTS: The patient graph had 93,000 relations between the 2794 patient nodes and 650 factor nodes. An LC graph with 187 related biomedical concepts and 188 horizontal biomedical relations was plotted and linked to the patient graph. Searching the integrated biomedical graph with any number or category of health factors resulted in graphical representations of relationships between patients and factors, while searches using any patient presented the patient's health factors from the EMR and the LC knowledge graph (KG) from the UMLS in the same graph. Sorting the health factors by CDR in descending order generated a distribution of health factors for LC. The top 70 CDR-ranked factors of disease, symptom, medical history, observation, and laboratory test categories were verified to be concordant with those found in the literature. CONCLUSIONS: By collecting standardized data of thousands of patients with and those without LC from the EMR, it was possible to generate a hospital-wide patient-centered health factor graph for graph search and presentation. The patient graph could be integrated with the UMLS KG for LC and thus enable hospitals to bring continuously updated international standard biomedical KGs from the UMLS for clinical use in hospitals. CDR analysis of the graph of patients with LC generated a CDR-sorted distribution of health factors, in which the top CDR-ranked health factors were concordant with the literature. The resulting distribution of LC health factors can be used to help personalize risk evaluation and preventive screening recommendations.


Assuntos
Registros Eletrônicos de Saúde , Neoplasias Pulmonares , Humanos , Estudos Retrospectivos , Unified Medical Language System , Neoplasias Pulmonares/epidemiologia , Hospitais
9.
Zhongguo Zhong Yao Za Zhi ; 47(21): 5757-5764, 2022 Nov.
Artigo em Zh | MEDLINE | ID: mdl-36471993

RESUMO

Taking Pudilan Xiaoyan Oral Liquid as a demonstration, the effective delivery of quality markers in alcohol precipitation of Chinese medicine oral liquid preparations was studied. With the transfer rates of adenosine, corynoline, cichoric acid, baicalin, and wogonin as evaluation indexes, the effect of the density of concentrate before alcoholic precipitation, volume fraction of ethanol, stirring speed, temperature of concentrated solution, stirring time, alcohol concentration, alcohol precipitation time, alcoholic precipitation temperature, alcohol addition rate, and the pH of concentrate on the alcohol precipitation process was investigated by Plackett-Burman trial design, thus obtaining the key factors that influenced the alcohol precipitation process. The key factors were further optimized by Box-Behnken design to determine the optimal alcohol precipitation conditions. When the density of concentrate before alcoholic precipitation was 1.12 g·mL~(-1), the pH of concentrate was 6.86, and the alcohol concentration was 50.00%, the transfer rates of baicalin and wogonin were 91.86% and 87.78%, respectively. When the density of concentrate before alcoholic precipitation was 1.13 g·mL~(-1), the concentration of alcohol was 74.50%, and the alcoholic precipitation temperature was 17.0 ℃, the transfer rates of adenosine, corynoline, and cichoric acid were 85.95%, 71.62% and 83.19%, respectively. The method of optimizing alcohol precipitation techniques and determining the parameters of Pudilan Xiaoyan Oral Liquid by response surface methodology is reasonable and feasible, which provides guidance and experience for the effective delivery of quality markers in Chinese medicine oral liquid preparations.


Assuntos
Medicamentos de Ervas Chinesas , Etanol , Adenosina , Precipitação Química
10.
Biomacromolecules ; 22(2): 546-556, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33449619

RESUMO

Silk fibroin films are used in tissue engineering due to their biocompatibility, optical clarity, and slow biodegradability. However, the relatively smooth surface and low permeability of these systems may limit some applications; thus, here, a method was developed to generate nano-pores in methanol or ethanol-treated silk fibroin films. The first step was to induce the formation of nanoparticles (50-300 nm diam.) in silk fibroin solutions by autoclaving. After drying in air, the films formed were treated to induce silk ß-sheet structures, which condense the bulk silk phase and nanoparticles and phase separation and enlarge the space of bulk silk phase and nanoparticles. These films were then extracted with water to allow the condensed nanoparticles to escape, leaving homogeneous nano-pores (50-300 nm) in the silk fibroin matrix. The introduction of nano-pores resulted in enhanced permeability and minimized loss of the mechanical properties of the nano-porous silk fibroin films (NSFs) when compared to the un-autoclaving-treated silk fibroin films. NSFs promoted cell (human fibroblasts) proliferation and oxygen/nutrition perfusion and significantly enhanced the complete skin-thickness wound healing in a rat model, suggesting the potential use in tissue regeneration or as wound dressing biomaterials for clinical applications.


Assuntos
Fibroínas , Nanopartículas , Animais , Materiais Biocompatíveis , Ratos , Seda , Engenharia Tecidual , Cicatrização
11.
Nano Lett ; 20(10): 7594-7599, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32936650

RESUMO

Non-Hermitian systems, with symmetric or antisymmetric Hamiltonians under the parity-time (PT) operations, can have entirely real or imaginary eigenvalues. This fact has led to surprising discoveries such as loss-induced lasing and topological energy transfer. A merit of anti-PT systems is free of gain, but in recent efforts on making anti-PT devices, nonlinearity is still required. Here, counterintuitively, we show how to achieve anti-PT symmetry and its spontaneous breaking in a linear device by spinning a lossy resonator. Compared with a Hermitian spinning device, significantly enhanced optical isolation and ultrasensitive nanoparticle sensing are achievable in the anti-PT-broken phase. In a broader view, our work provides a new tool to study anti-PT physics, with such a wide range of applications as anti-PT lasers, anti-PT gyroscopes, and anti-PT topological photonics or optomechanics.

12.
Int J Mol Sci ; 21(4)2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32085613

RESUMO

The black layer (BL) is traditionally used as an indicator for kernel harvesting in maize, as it turns visibly dark when the kernel reaches physiological maturity. However, the molecular roles of BL in kernel development have not been fully elucidated. In this work, microscopy images showed that BL began to appear at a growth stage earlier than 10 days after pollination (DAP), and its color gradually deepened to become dark as the development period progressed. Scanning electron microscopy observations revealed that BL is a tissue structure composed of several layers of cells that are gradually squeezed and compressed during kernel development. Laser-capture microdissection (LCM) was used to sample BL and its neighboring inner tissue, basal endosperm transfer layer (BETL), and outer tissue, inner epidermis (IEP), from 20 DAP of kernels. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry profiling (MALDI-TOF MS profiling) detected 41, 104, and 120 proteins from LCM-sampled BL, BETL, and IEP, respectively. Gene ontology (GO) analysis indicated that the 41 BL proteins were primarily involved in the response to stress and stimuli. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis found that the BL proteins were enriched in several defense pathways, such as the ascorbate and aldarate metabolic pathways. Among the 41 BL proteins, six were BL-specific proteins that were only detected from BL. Annotations of five BL-specific proteins were related to stress responses. During kernel development, transcriptional expression of most BL proteins showed an increase, followed by a decrease, and reached a maximum zero to 20 DAP. These results suggest a role for BL in stress responses for protecting filial tissue against threats from maternal sides, which helps to elucidate the biological functions of BL.


Assuntos
Microdissecção e Captura a Laser , Proteômica , Sementes/metabolismo , Estresse Fisiológico , Zea mays/fisiologia , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Genoma de Planta , Anotação de Sequência Molecular , Peptídeos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Coloração e Rotulagem , Zea mays/genética , Zea mays/crescimento & desenvolvimento
13.
Opt Express ; 27(20): 27649-27662, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684529

RESUMO

We propose how to mechanically control photon blockade (PB) and photon-induced tunneling (PIT) in an optomechanical system. We show that single-photon blockade (1PB) and two-photon blockade (2PB) can emerge by tuning mechanical driving parameters. Moreover, by varying the strength of mechanical driving, PIT can be converted into 1PB or 2PB, or vice versa, with the constant optical frequency. We refer to this effect as PIT-1PB or PIT-2PB switch. In addition, the switch between 1PB and 2PB can also be realized with this strategy. This mechanical engineering of quantum optical effects can be understood from the shifts of energy levels induced by external mechanical pumping. Our results not only pave the way towards devising new schemes for quantum light switch but also, on a more fundamental level, could shed light on the nonclassicality of the few-photon states.

14.
Molecules ; 24(18)2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527535

RESUMO

The study reported on the isolation of a metalloprotease named EH2 from Pseudoalteromonas sp. H2. EH2 maintained more than 80% activity over a wide pH range of 5-10, and the stability was also nearly independent of pH. Over 65% activity was detected at a wide temperature range of 20-70 °C. The high stability of the protease in the presence of different surfactants and oxidizing agents was also observed. Moreover, we also investigated the antioxidant activities of the hydrolysates generated from porcine and salmon skin collagen by EH2. The results showed that salmon skin collagen hydrolysates demonstrated higher DPPH (1,1-diphenyl-2-picrylhydrazyl) (42.88% ± 1.85) and hydroxyl radical (61.83% ± 3.05) scavenging activity than porcine skin collagen. For oxygen radical absorbance capacity, the hydrolysates from porcine skin collagen had higher efficiency (7.72 ± 0.13 µmol·TE/µmol). Even 1 nM mixed peptides could effectively reduce the levels of intracellular reactive oxygen species. The two types of substrates exerted the best antioxidant activity when hydrolyzed for 3 h. The hydrolysis time and type of substrate exerted important effects on the antioxidant properties of hydrolysates. The hydrolyzed peptides from meat collagens by proteases have good antioxidant activity, which may have implications for the potential application of marine proteases in the biocatalysis industry.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Peptídeo Hidrolases/química , Peptídeo Hidrolases/isolamento & purificação , Peptídeos/química , Peptídeos/isolamento & purificação , Pseudoalteromonas/enzimologia , Colágeno/metabolismo , Ativação Enzimática , Estabilidade Enzimática , Espaço Extracelular , Humanos , Concentração de Íons de Hidrogênio , Hidrólise
15.
Phys Rev Lett ; 121(15): 153601, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30362805

RESUMO

We propose how to create and manipulate one-way nonclassical light via photon blockade in rotating nonlinear devices. We refer to this effect as nonreciprocal photon blockade (PB). Specifically, we show that in a spinning Kerr resonator, PB happens when the resonator is driven in one direction but not the other. This occurs because of the Fizeau drag, leading to a full split of the resonance frequencies of the countercirculating modes. Different types of purely quantum correlations, such as single- and two-photon blockades, can emerge in different directions in a well-controlled manner, and the transition from PB to photon-induced tunneling is revealed as well. Our work opens up a new route to achieve quantum nonreciprocal devices, which are crucial elements in chiral quantum technologies or topological photonics.

16.
J Magn Reson Imaging ; 43(1): 75-87, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26094886

RESUMO

PURPOSE: To explore mild cognitive dysfunction and/or spatial working memory impairment in patients with primary onset middle-age type 2 diabetes mellitus (T2DM] using ethology (behavior tests) and blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI). MATERIALS AND METHODS: Eighteen primary onset T2DM patients and 18 matched subjects with normal blood glucose levels were all tested using the Montreal cognitive assessment scale test, the Wechsler Memory Scale Chinese-revised test, and scanned using BOLD-fMRI (1.5T, EPI sequence) while performing the n-back task to find the activation intensity of some cognition-related areas. RESULTS: The ethology results showed that T2DM patients had a mild cognitive impairment and memory dysfunction (P < 0.05). The fMRI scan identified a neural network consisting of bilateral dorsolateral prefrontal cortex (DLPFC), bilateral premotor area (PreMA), bilateral parietal lobe (PA), and anterior cingulate cortex (ACC) / supplementary motor area (SMA) that was activated during the n-back task, with right hemisphere dominance. However, only the right PA and ACC/SMA showed a load effect via quantitative analysis in the T2DM group; the activation intensity of most working memory-related brain areas for the T2DM group were lower than for the control group under three memory loads. Furthermore, we found that the activation intensity of some cognition-related areas, including the right insular lobe, left caudate nucleus, and bilateral hippocampus/parahippocampal gyrus were lower than the control group under the memory loads. CONCLUSION: Diabetes-related brain damage of primary onset middle-age T2DM patients with right DLPFC-posterior parietal lobe and parahippocampal gyrus default network causes impairment of spatial working memory and mild cognitive dysfunction.


Assuntos
Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Hipocampo/fisiopatologia , Transtornos da Memória/fisiopatologia , Adulto , Mapeamento Encefálico/métodos , Transtornos Cognitivos/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Transtornos da Memória/diagnóstico , Transtornos da Memória/etiologia , Memória de Curto Prazo , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Phys Chem Chem Phys ; 18(5): 4134-43, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26782968

RESUMO

A multi-leveled theoretical investigation combining TD-DFT (B3LYP and CAM-B3LYP) methods and a semi-empirical method was conducted to determine the structure-related spectral properties of T-series dendrimers composed of nearly hundreds of atoms, based on a proposed molecular model. Both one- and two-photon absorption spectra of the dendrimer molecules were well reproduced. The "antenna effect" in the dendrimers molecule was theoretically studied. The process of excitation energy localization from chromophores in the branches to the pyrene core before the fluorescence emission was visualized using contours of the charge different density (CDD) between the electronic states. Conclusions based on the theoretical model were drawn about the observed photophysical properties of T-series dendrimers as follows: (a) increasing the generation of a branch would enhance the absorption of photons with a wavelength below 430 nm; (b) enlarging the conjugation of branches would enhance the coupling among the chromophores and would lower the excitation energy;

18.
Appl Opt ; 55(9): 2393-8, 2016 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-27140579

RESUMO

Yarn tension is an important parameter for assuring textile quality. In this paper, an optical method to measure microtension of moving yarn automatically in the winding system is proposed. The proposed method can measure microtension of the moving yarn by analyzing the captured images. With a line laser illuminating the moving yarn, a linear array CCD camera is used to capture the images. Design principles of yarn microtension measuring equipment based on computer vision are presented. A local border difference algorithm is used to search the upper border of the moving yarn as the characteristic line, and Fourier descriptors are used to filter the high-frequency noises caused by unevenness of the yarn diameter. Based on the average value of the characteristic line, the captured images were classified into sagging images and vibration images. The average value is considered a sag coordinate of the sagging images. The peak and trough coordinates of the vibration are obtained by change-point detection. Then, according to axially moving string and catenary theory, we obtain the microtension of the moving yarn. Experiments were performed and compared with a resistance strain sensor, and the results prove that the proposed method is effective and of high accuracy.

19.
Opt Express ; 22 Suppl 6: A1567-75, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25607314

RESUMO

A two-axis tracking scheme designed for <250x concentration realized by a single-axis mechanical tracker and a translation stage is discussed. The translation stage is used for adjusting positions for seasonal sun movement. It has two-dimensional x-y tracking instead of horizontal movement x-only. This tracking method is compatible with planar waveguide solar concentrators. A prototype system with 50x concentration shows >75% optical efficiency throughout the year in simulation and >65% efficiency experimentally. This efficiency can be further improved by the use of anti-reflection layers and a larger waveguide refractive index.


Assuntos
Fontes de Energia Elétrica , Lentes , Fotometria/instrumentação , Robótica/instrumentação , Energia Solar , Ressonância de Plasmônio de Superfície/instrumentação , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Movimento (Física) , Refratometria/instrumentação , Espalhamento de Radiação
20.
Opt Express ; 22 Suppl 2: A198-204, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24922228

RESUMO

We present a lens-to-channel waveguide solar concentrator, where the lens array and the channel waveguide act as the primary and the secondary concentrator. Sunlight collected by the lens array is coupled into channel waveguides and exits from one end of the tapered waveguide directly onto photovoltaic cells. A 45°coupler is placed at each lens focal point to couple light into the waveguides. This configuration eliminates any inherent decoupling losses. We provide a detailed math model and simulation results using exemplar system parameters, showing that this structure can achieve 800x concentration at 89.1% optical efficiency under ±0.7° incidence angle.

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