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1.
J Formos Med Assoc ; 120(1 Pt 1): 234-241, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32414667

RESUMO

BACKGROUND/PURPOSE: Metabolites in blood have been found associated with the occurrence of vascular diseases, but its role in the functional recovery of stroke is unclear. The aim of this study is to investigate whether the untargeted metabolomics at the acute stage of ischemic stroke is able to predict functional recovery. METHODS: One hundred and fifty patients with acute ischemic stroke were recruited and followed up for 3 months. Fasting blood samples within 7 days of stroke were obtained, liquid chromatography and mass spectrometry were applied to identify outcome-associated metabolites. The patients' clinical characteristics and identified metabolites were included for constructing the outcome prediction model using machine learning approaches. RESULTS: By using multivariate analysis, 220 differentially expressed metabolites (DEMs) were discovered between patients with favorable outcomes (modified Rankin Scale, mRS ≤ 2 at 3 months, n = 77) and unfavorable outcomes (mRS ≥ 3 at 3 months, n = 73). After feature selection, 63 DEMs were chosen for constructing the outcome prediction model. The predictive accuracy was below 0.65 when including patients' clinical characteristics, and could reach 0.80 when including patients' clinical characteristics and 63 selected DEMs. The functional enrichment analysis identified platelet activating factor (PAF) as the strongest outcome-associated metabolite, which involved in proinflammatory mediators release, arachidonic acid metabolism, eosinophil degranulation, and production of reactive oxygen species. CONCLUSION: Metabolomics is a potential method to explore the blood biomarkers of acute ischemic stroke. The patients with unfavorable outcomes had a lower PAF level compared to those with favorable outcomes.

2.
Sci Total Environ ; 753: 141774, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33207436

RESUMO

Atmospheric fine particulate matter (PM2.5) causes severe haze in China and is regarded as a threat to human health. The health effects of PM2.5 vary location by location due to the variation in size distribution, chemical composition, and sources. In this study, the cytotoxicity effect, oxidative stress, and gene expression regulation of PM2.5 in Chengdu and Chongqing, two typical urban areas in southern China, were evaluated. Urban PM2.5 in summer and winter significantly inhibited cell viability and increased reactive oxygen species (ROS) levels in A549 cells. Notably, PM2.5 in winter exhibited higher cytotoxicity and ROS level than summer. Moreover, in this study, PM2.5 commonly induced cancer-related gene expression such as cell adhesion molecule 1 (PECAM1), interleukin 24 (IL24), and cytochrome P450 (CYP1A1); meanwhile, PM2.5 commonly acted on cancer-related biological functions such as cell-substrate junction, cell-cell junction, and focal adhesion. In particular, PM2.5 in Chengdu in summer had the highest carcinogenic potential among PM2.5 at the two sites in summer and winter. Importantly, cancer-related genes were uniquely targeted by PM2.5, such as epithelial splicing regulatory protein 1 (ESRP1) and membrane-associated ring-CH-type finger 1 (1-Mar) by Chengdu summer PM2.5; collagen type IX alpha 3 chain (COL9A3) by Chengdu winter PM2.5; SH2 domain-containing 1B (SH2D1B) by Chongqing summer PM2.5; and interleukin 1 receptor-like 1 (IL1RL1) and zinc finger protein 42 (ZNF423) by Chongqing winter PM2.5. Meanwhile, important cancer-related biological functions were specially induced by PM2.5, such as cell cycle checkpoint by Chengdu summer PM2.5; macromolecule methylation by Chengdu winter PM2.5; endoplasmic reticulum-Golgi intermediate compartment membrane by Chongqing summer PM2.5; and cellular lipid catabolic process by Chongqing winter PM2.5. Conclusively, in the typical urban areas of southern China, both summer and winter PM2.5 illustrated significant gene regulation effects. This study contributes to evaluating the adverse health effects of PM2.5 in southern China and providing public health suggestions for policymakers.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , China , Monitoramento Ambiental , Regulação da Expressão Gênica , Humanos , Material Particulado/análise , Material Particulado/toxicidade , Estações do Ano , Fatores de Transcrição
3.
Phys Chem Chem Phys ; 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33155610

RESUMO

Propionaldehyde is one of the most abundant aldehydes, which are an important class of volatile organic compounds. In this work, the rate coefficient of the reaction of the simplest Criegee intermediate CH2OO with propionaldehyde (CH3CH2CHO) was measured for the first time in a flash photolysis reaction tube by using the OH laser-induced fluorescence (LIF) method at temperature and pressure in the range of 283 to 318 K and 5 to 200 Torr. This reaction is observed to be pressure- and temperature-dependent. The measured rate coefficient at 50 Torr is in the vicinity of the high-pressure limit value of (3.23 ± 0.49) × 10-12 cm3 s-1 at 298 K, which is in agreement with a previously reported theoretical result of 2.44 × 10-12 cm3 s-1. The Arrhenius plot of the temperature-dependent rate coefficients yields an activation energy of (-1.99 ± 0.23) kcal mol-1.

4.
Lipids Health Dis ; 19(1): 231, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33143696

RESUMO

BACKGROUND: Data on the relationship between nontraditional lipid profiles [total cholesterol (TC)/high-density lipoprotein cholesterol (HDL-C) ratio, triglyceride (TG)/HDL-C ratio, low-density lipoprotein cholesterol (LDL-C)/HDL-C ratio, non-high-density lipoprotein cholesterol (non-HDL-C)] and the risk of peripheral artery disease (PAD) are limited. The present study investigated the relationship of nontraditional lipid indices with PAD in hypertensive patients. METHODS: This cross-sectional study was performed among 10,900 adults with hypertension. Participants were diagnosed with PAD when their ankle-brachial index (ABI) was < 0.9. The association between nontraditional lipid profiles and PAD was examined using multivariate logistic regression analysis and the restricted cubic spline. RESULTS: All nontraditional lipid indices were independently and positively associated with PAD in a dose-response fashion. After multivariable adjustment, the per SD increments of the TC/HDL-C, TG/HDL-C, LDL-C/HDL-C ratios and non-HDL-C were all significantly associated with 37, 14, 40, and 24% higher risk for PAD, respectively. The adjusted ORs (95% CI) for PAD were 1.77 (1.31, 2.40), 1.71 (1.25, 2.34), 2.03 (1.50, 2.74), and 1.70 (1.25, 2.31) when comparing the highest tertile to the lowest tertile of the TC/HDL-C, TG/HDL-C, LDL-C/HDL-C ratios and non-HDL-C, respectively. CONCLUSIONS: Among Chinese hypertensive adults, all nontraditional lipid indices were positively associated with PAD, and the LDL-C/HDL-C and TC/HDL-C ratios were better than the other nontraditional lipid indices for predicting PAD. These findings may improve the risk stratification of cardiovascular disease and dyslipidemia management. TRIAL REGISTRATION: CHiCTR, ChiCTR1800017274 . Registered 20 July 2018.

5.
Chem Soc Rev ; 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33135691

RESUMO

Over the past two decades, the development and application of ynamide chemistry have received more and more attention. Ynamides have proven to be versatile reagents for organic synthesis, and have been widely applied to the rapid assembly of a diverse range of structurally complex N-containing molecules, especially the valuable N-heterocycles. In comparison with the well-established transition metal-catalyzed reactions of ynamides, metal-free ynamide transformations have relatively seldom been exploited. Recently, Brønsted acid-mediated reactions of ynamides represent significant advances in ynamide chemistry. This review summarizes the latest trends and developments of Brønsted acid-mediated reactions of ynamides, including cycloaddition, cyclization, intramolecular alkoxylation-initiated rearrangement, oxygen atom transfer reactions and hydro-heteroatom addition reactions.

6.
Am J Sports Med ; : 363546520962774, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33136424

RESUMO

BACKGROUND: A repaired rotator cuff (RC) often heals with interposed scar tissue, making repairs prone to failure. Urine-derived stem cells (USCs), with robust proliferation ability and multilineage differentiation, can be isolated from urine, avoiding invasive and painful surgical procedures for harvesting the cells. These advantages make it a novel cell source for autologous transplantation to enhance RC healing. HYPOTHESIS: Implantation of an autogenous USC sheet to the injury site will enhance RC healing. STUDY DESIGN: Controlled laboratory study. METHODS: USCs isolated from urine were cultured using ascorbic acid and transforming growth factor ß3 to form a cell sheet. Sixteen male mature beagles underwent bilateral shoulder surgery. The right shoulder underwent infraspinatus tendon (IT) insertion detachment and repair only, and the other was subjected to IT insertion detachment and repair, followed by autogenous USC sheet implantation. Among the animals, 3 received a Dil (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate)- labeled USC sheet implant in the right shoulder and were sacrificed at postoperative 6 weeks for cell tracking. The other animals were sacrificed at postoperative 12 weeks, and the IT-humerus complexes were harvested for gross observation, micro-computed tomography evaluation and histological analysis (n = 5), and mechanical testing (n = 8). Additionally, 13 unpaired canine cadaveric shoulders were included as native controls. RESULTS: Micro-computed tomography analysis showed that the USC sheet group had a significant increase in bone volume/total volume and trabecular thickness at the RC healing site when compared with the control group (P < .05 for all). Histologically, the Dil-labeled USC sheet was still visible at the RC healing site, which suggested that the implanted USCs remained viable at postoperative 6 weeks. Meanwhile, the healing interface in the USC sheet group regenerated significantly more enthesis-like tissue than did that of the control group (P < .05). Additionally, the healing interface in the USC sheet group presented a larger fibrocartilage area, more proteoglycan deposition, and higher collagen birefringence than did that of the control group (P < .05 for all). Biomechanically, the USC sheet group showed significantly higher failure load and stiffness versus the control group (P < .05 for all). CONCLUSION: A USC sheet was able to enhance RC healing in a canine model. CLINICAL RELEVANCE: The findings of the study showed that USC sheet implantation could serve as a practical application for RC healing.

7.
Brief Bioinform ; 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33140820

RESUMO

Effective drug discovery contributes to the treatment of numerous diseases but is limited by high costs and long cycles. The Quantitative Structure-Activity Relationship (QSAR) method was introduced to evaluate the activity of a large number of compounds virtually, reducing the time and labor costs required for chemical synthesis and experimental determination. Hence, this method increases the efficiency of drug discovery. To meet the needs of researchers to utilize this technology, numerous QSAR-related web servers, such as Web-4D-QSAR and DPubChem, have been developed in recent years. However, none of the servers mentioned above can perform a complete QSAR modeling and supply activity prediction functions. We introduce Cloud 3D-QSAR by integrating the functions of molecular structure generation, alignment, molecular interaction field (MIF) computing and results analysis to provide a one-stop solution. We rigidly validated this server, and the activity prediction correlation was R2 = 0.934 in 834 test molecules. The sensitivity, specificity and accuracy were 86.9%, 94.5% and 91.5%, respectively, with AUC = 0.981, AUCPR = 0.971. The Cloud 3D-QSAR server may facilitate the development of good QSAR models in drug discovery. Our server is free and now available at http://chemyang.ccnu.edu.cn/ccb/server/cloud3dQSAR/ and http://agroda.gzu.edu.cn:9999/ccb/server/cloud3dQSAR/.

8.
Mikrochim Acta ; 187(12): 637, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33146801

RESUMO

A miniaturized and integrated bioassay was developed based on molybdenum disulfide (MoS2) field-effect transistor (FET) functionalized with bovine serum albumin-folic acid (BSA-FA) for monitoring FOLR1. We performed the electrical test of FOLR1 within the range 100 fg/mL to 10 ng/mL, and the limit of detection was 0.057 pg/mL. The ultrahigh sensitivity of the bioassay was realized by ligand-protein interaction between FA and FOLR1, with a ligand-protein binding ratio of 3:1. The formation of FA-FOLR1 was confirmed with ELISA. The binding affinity dissociation constant KD was 12 ± 6 pg/mL. This device can work well for FOLR1 detection in human serum, which presents its promising application in point-of-care diagnosis. This study supports the future applications of such ligand-protein-based bioassays in the clinical practices. Graphical abstract MoS2-based FET device for detecting folate receptor 1 (FOLR1) was fabricated. The molecular folic acid as a probe can specifically bound to FOLR1 with a high affinity.

9.
Mol Biol Evol ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33170928

RESUMO

The Taiwanese people are composed of diverse indigenous populations and the Taiwanese Han. About 95% of the Taiwanese identify themselves as Taiwanese Han, but this may not be a homogeneous population because they migrated to the island from various regions of continental East Asia over a period of 400 years. Little is known about the underlying patterns of genetic ancestry, population admixture, and evolutionary adaptation in the Taiwanese Han people. Here, we analyzed the whole-genome SNP genotyping data from 14,401 individuals of Taiwanese Han collected by the Taiwan Biobank and the whole-genome sequencing data for a subset of 772 people. We detected four major genetic ancestries with distinct geographic distributions (i.e., Northern, Southeastern, Japonic, and Island Southeast Asian ancestries) and signatures of population mixture contributing to the genomes of Taiwanese Han. We further scanned for signatures of positive natural selection that caused unusually long-range haplotypes and elevations of hitchhiked variants. As a result, we identified 16 candidate loci in which selection signals can be unambiguously localized at five single genes: CTNNA2, LRP1B, CSNK1G3, ASTN2, and NEO1. Statistical associations were examined in 16 metabolic-related traits to further elucidate the functional effects of each candidate gene. All five genes appear to have pleiotropic connections to various types of disease susceptibility and significant associations with at least one metabolic-related trait. Together, our results provide critical insights for understanding the evolutionary history and adaption of the Taiwanese Han population.

10.
Phys Chem Chem Phys ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33169125

RESUMO

Covering about 70% of the earth's surface, water contains considerable energy that remains unexploited. Superhydrophobic surfaces (SHSs) possess excellent water repellency, and energy conversion based on SHSs has opened up a new avenue for efficient collection and utilization of water energy. Therefore, it is of great significance to efficiently prepare SHSs and apply them for energy conversion in different fields. In this review, we first summarize the fabrication methods of SHSs, and then provide an overview of the energy conversion forms based on SHSs. Finally, the related applications corresponding to the energy conversion forms are introduced, including renewable energy collection and utilization, wearable device design, use of liquid sensors, surface cooling and heat dissipation, self-propelled devices, droplet manipulation and lab-on-a-chip devices; and their challenges and future perspectives are highlighted.

11.
Int J Pharm ; : 120081, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33189810

RESUMO

The concept of skin-specific drug delivery with a spatio-temporal control has just recently received concerns in dermatology. Inspired by the progress in smart materials and their perspective application in medicine science, development of stimuli responsive drug delivery systems with skin-specificity has become possible, which has led to a new era in the localized treatment of skin diseases. This review highlights both the internal and external stimuli that have been employed in this field, with a focus on their implication on the rational design of pharmaceutical formulations, especially those nanoscale drug carriers that are able to provide release of payloads with a precise spatio-temporal control in response to specific stimuli. Also, the strategy of dual stimuli responsive drug delivery systems will be discussed for further improvement of the efficacy of skin drug delivery. The prominent examples of the established approaches are described as comprehensive and current as possible. The review is expected to provide some inspiration for utilizing different stimuli for realizing the site-specific and on-demand drug delivery to the skin.

12.
Harmful Algae ; 99: 101911, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33218437

RESUMO

The phytoplankton Phaeocystis globosa thrives in a wide range of marine regions and plays an important role in climate control. It can also form harmful algal blooms (HABs) that threaten environments and impact important coastal infrastructures. Mechanisms underlying the formation of P. globosa blooms still remain poorly understood. Accumulating evidence suggests that P. globosa has high genetic diversity and different P. globosa strains may have differential contributions to the development of P. globosa blooms. However, due to the lack of molecular markers with adequate resolution for distinguishing P. globosa genetic diversity, such differential contributions by different P. globosa strains could not be accurately ascertained. As such, high-resolution molecular markers need to be developed and applied to distinguish P. globosa genetic diversity. In this study, we undertook to define high-resolution molecular marker by assembling and comparing the whole chloroplast genomes of P. globosa strains isolated from different regions of the world. Through comparative analysis of P. globosa cpDNAs and detection of single nucleotide variations (SNVs), a molecular marker pgcp1 with improved resolution was developed. The pgcp1 demonstrated the highest resolution compared with other regions including 18S rDNA V4 region, 28S rDNA D1-D2 region and rbcL region, through genetic distance and phylogenetic analysis of 13 P. globosa strains. Molecular analysis of environmental samples and strains collected in multiple expeditions from a wide range of ocean regions including multiple regions in China, Vietnam, Thailand and Western Pacific using pgcp1 as the molecular marker displayed high genetic diversity of P. globosa with at least four major P. globosa clades. In conclusion, we have developed pgcp1 as a high-resolution molecular marker for the harmful algal bloom species P. globosa, which can be used to track intra-species genetic diversity and dynamics of P. globosa during bloom development.

13.
Anal Chim Acta ; 1140: 18-29, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33218480

RESUMO

BACKGROUND: Metabolomics strategy was perform to identify the novel serum biomarkers linked to schizophrenia with the assistance of transcriptomics analysis. METHODS: Two analytical platforms, UPLC-Q-TOF MS/MS and 1H NMR, were used to acquire the serum fingerprinting profiles from a total of 112 participants (57 healthy controls and 55 schizophrenia patients). The differential metabolites were primarily selected after statistical analyses. Meanwhile, GSE17612 dataset downloaded from GEO database was implemented WGCNA analysis to discover crucial genes and corresponding biological processes. Based on metabolomics analysis, the metabolic distinctions were explored under the aid of transcriptomics. Then using Boruta algorithm identified the biomarkers, and LASSO regression analysis and Random Forest algorithm were used to evaluate the performance of the diagnostic model constructed by biomarkers selected. RESULTS: A total of four metabolites (α-CEHC, neuraminic acid, glyceraldehyde and asparagine) were selected as the biomarkers to establish diagnosis model. The performance of this model showed a higher accuracy rate to distinguish schizophrenia patients from healthy controls (area under the receive operating characteristic curve, 0.992; precision recall curve, 1.000, the mean accuracy of random forest algorithm, 95.00%). CONCLUSIONS: A four-biomarker model (α-CEHC, neuraminic acid, glyceraldehyde and asparagine) seems to be a good model for diagnosing schizophrenia patients. It might be helpful to guide the future studies on permitting early intervention designed to prevent disease progression.

15.
HIV Med ; 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33197141

RESUMO

OBJECTIVES: Despite being a key population in whom to initiate pre-exposure prophylaxis (PrEP), the awareness of and willingness to use PrEP are still unclear in Chinese young men who have sex with men (YMSM). We report factors associated with PrEP awareness and willingness in the population. METHODS: From 1 August to 31 December 2018, 495 participants aged 15-24 years were included in a cross-sectional study about awareness of and willingness to use PrEP among YMSM. Logistic regression models were used to identify factors associated with two outcomes: awareness of PrEP; and willingness to use PrEP. RESULTS: Among 495 eligible participants, 129 participants (26.1%) knew about PrEP. PrEP awareness among YMSM was associated with higher education level [adjusted odds ratio (aOR) = 1.812, 95% CI: 1.113-2.951] and previous HIV testing (aOR = 3.507, 95% CI: 1.261-9.752). YMSM with shorter local residence time (aOR = 0.317, 95% CI: 0.101-0.992) and internet-based partner-seeking (aOR = 0.171, 95% CI: 0.096-0.305) were less likely to be aware of PrEP. In those with previous knowledge of PrEP, 36 (27.9%) conveyed their willingness to use it. PrEP willingness was associated with internet-based partner-seeking (aOR = 9.593, 95% CI: 1.965-46.844). The main barriers influencing those who knew about PrEP but refused to use it were the high price of PrEP (69.9%), the need to use condoms consistently (52.7%), and concerns about side effects (39.8%) and effectiveness of prevention (22.6%). CONCLUSIONS: Chinese YMSM have low awareness of and willingness to use PrEP. Adequate PrEP promotions should be implemented, especially on the Internet and dating software.

16.
Nutrients ; 12(11)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198366

RESUMO

High birth weight indicates the future risk of obesity and increased fat mass in childhood. Maternal gestational diabetes mellitus (GDM) or overweight are powerful predictors of high birth weight. Studies on probiotic supplementation during pregnancy have reported its benefits in modulating gut microbiota composition and improving glucose and lipid metabolism in pregnant women. Therefore, probiotic intervention during pregnancy was proposed to interrupt the transmission of obesity from mothers to newborns. Thus, we performed a meta-analysis to investigate the effect of probiotic intervention in pregnant women with GDM or overweight on newborn birth weight. We searched PubMed, EMBASE, Cochrane Library, and Web of Science databases up to 18 December 2019. Randomized controlled trials (RCTs) comparing pregnant women with GDM or overweight who received probiotic intervention during pregnancy with those receiving placebo were eligible for the analysis. Newborn birth weights were pooled to calculate the mean difference with a 95% confidence interval (CI). Two reviewers assessed the trial quality and extracted data independently. Seven RCTs involving 1093 participants were included in the analysis. Compared with the placebo, probiotics had little effect on newborn birth weight of pregnant women with GDM or overweight (mean difference = -10.27, 95% CI = -90.17 to 69.63, p = 0.801). The subgroup analysis revealed that probiotic intake by women with GDM decreased newborn birth weight, whereas probiotic intake by obese pregnant women increased newborn birth weight. Thus, no evidence indicates that probiotic intake by pregnant women with GDM or overweight can control newborn birth weight.

17.
Palliat Med ; : 269216320972041, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33198575

RESUMO

BACKGROUND: Evaluating the need for palliative care and predicting its mortality play important roles in the emergency department. AIM: We developed a screening model for predicting 1-year mortality. DESIGN: A retrospective cohort study was conducted to identify risk factors associated with 1-year mortality. Our risk scores based on these significant risk factors were then developed. Its predictive validity performance was evaluated using area under receiving operating characteristic analysis and leave-one-out cross-validation. SETTING AND PARTICIPANTS: Patients aged 15 years or older were enrolled from June 2015 to May 2016 in the emergency department. RESULTS: We identified five independent risk factors, each of which was assigned a number of points proportional to its estimated regression coefficient: age (0.05 points per year), qSOFA ⩾ 2 (1), Cancer (4), Eastern Cooperative Oncology Group Performance Status score ⩾ 2 (2), and Do-Not-Resuscitate status (3). The sensitivity, specificity, positive predictive value, and negative predictive value of our screening tool given the cutoff larger than 3 points were 0.99 (0.98-0.99), 0.31 (0.29-0.32), 0.26 (0.24-0.27), and 0.99 (0.98-1.00), respectively. Those with screening scores larger than 9 points corresponding to 64.0% (60.0-67.9%) of 1-year mortality were prioritized for consultation and communication. The area under the receiving operating characteristic curves for the point system was 0.84 (0.83-0.85) for the cross-validation model. CONCLUSIONS: A-qCPR risk scores provide a good screening tool for assessing patient prognosis. Routine screening for end-of-life using this tool plays an important role in early and efficient physician-patient communications regarding hospice and palliative needs in the emergency department.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33199637

RESUMO

A key step of decision making is to determine the value associated with each option. The evaluation process often depends on the accumulation of evidence from multiple sources, which may arrive at different times. How evidence is accumulated for value computation in the brain during decision making has not been well studied. To address this problem, we trained rhesus monkeys to perform a decision-making task in which they had to make eye movement choices between two targets, whose reward probabilities had to be determined with the combined evidence from four sequentially presented visual stimuli. We studied the encoding of the reward probabilities associated with the stimuli and the eye movements in the orbitofrontal (OFC) and the dorsolateral prefrontal (DLPFC) cortices during the decision process. We found that the OFC neurons encoded the reward probability associated with individual pieces of evidence in the stimulus domain. Importantly, the representation of the reward probability in the OFC was transient, and the OFC did not encode the reward probability associated with the combined evidence from multiple stimuli. The computation of the combined reward probabilities was observed only in the DLPFC and only in the action domain. Furthermore, the reward probability encoding in the DLPFC exhibited an asymmetric pattern of mixed selectivity that supported the computation of the stimulus-to-action transition of reward information. Our results reveal that the OFC and the DLPFC play distinct roles in the value computation during evidence accumulation.

19.
Biomater Sci ; 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33201168

RESUMO

The whole is a collection of parts and fulfills specific functions that the parts do not have. In this work, 50 nm Au NPs were in situ synthesized and close packed into a superorganism-like superstructure by means of microgel 3D networks. The combined microgel is endowed with ultra-wide absorption in visible and near-infrared regions between 500 and 1100 nm in spite of Au NPs not having this property. The strong collective plasmon coupling between neighboring Au NPs induces high photothermal conversion efficiency of the microgel system under irradiation at various laser wavelengths. Due to the good loading capability, microgels with nanocomposites can also load photosensitive drugs simultaneously and be used for combined cancer treatments of photothermal therapy and photodynamic therapy.

20.
J Hazard Mater ; : 124504, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33229261

RESUMO

Ordinary Portland cement (OPC) clinker mainly consist four minerals, tricalcium silicate (C3S), dicalcium silicate (C2S,), tricalcium aluminate (C3A), and tetracalcium aluminoferrite (C4AF). To learn the doping behaviors of Zn in OPC clinker, a series of samples were prepared by calcinating the mixtures of CaCO3, SiO2, Al2O3, Fe2O3, and ZnO. Our results from energy-dispersive spectroscopy, X-ray diffraction and density functional theoretical simulations show that a small amount of ZnO enter C3S and C2S by replacing Ca ions while most incorporate into C4AF by substituting Fe atoms, resulting in a decrease of C3A in OPC as dosage increases. Further analyses from partial density of states and distributions of bond order-bond length indicate that the doping preference can be ascribed to the similar electron contributions and small structure distortions between host and guest ions. Unlike the strong Fe‒O bond, the newly formed Zn‒O is much weaker. The weak Zn‒O may be responsible for the limited solubility of Zn in C4AF. These results provide a possibility of increasing solubility of Zn in OPC clinker by increasing the contents of C3A and C4AF, thus will be very meaningful in the synthesis of OPC clinker by utilizing Zn-bearing alternative raw materials.

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