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1.
J Med Virol ; 96(2): e29442, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38294063

RESUMO

Starting from May 31, 2023, the local transmission of monkeypox (Mpox) in mainland China began in Beijing. Till now, the transmission characteristics have not been explored. Based on the daily Mpox incidence data in the first 3 weeks of Beijing (from May 31 to June 21, 2023), we employed the instant-individual heterogeneity transmission model to simultaneously calculate the effective reproduction number (Re ) and the degree of heterogeneity (k) of the Beijing epidemic. We additionally simulated the monthly infection size in Beijing from July to November and compared with the reported data to project subsequent transmission dynamics. We estimated Re to be 1.68 (95% highest posterior density [HPD]: 1.12-2.41), and k to be 2.57 [95% HPD: 0.54-83.88], suggesting the transmission of Mpox in Beijing was supercritical and didn't have considerable transmission heterogeneity. We projected that Re fell in the range of 0.95-1.0 from July to November, highlighting more efforts needed to further reduce the Mpox transmissibility. Our findings revealed supercritical and homogeneous transmission of the Mpox epidemic in Beijing. Our results could serve as a reference for understanding and predicting the ongoing Mpox transmission in other regions of China and evaluating the effect of control measures.


Assuntos
Epidemias , Mpox , Humanos , Mpox/epidemiologia , China/epidemiologia , Pequim , Número Básico de Reprodução
2.
Reprod Biol Endocrinol ; 21(1): 8, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36703171

RESUMO

STUDY QUESTION: To construct prediction models based on the Bayesian network (BN) learning method for the probability of fertilization failure (including low fertilization rate [LRF] and total fertilization failure [TFF]) in assisted reproductive technology (ART) treatment. A BN model was developed to predict TFF/LFR. The model showed relatively high calibration in external validation, which could facilitate the identification of risk factors for fertilization disorders and improve the efficiency of in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment. WHAT IS KNOWN ALREADY: The prediction of TFF/LFR is very complex. Although some studies attempted to construct prediction models for TFF/LRF, most of the reported models were based on limited variables and traditional regression-based models, which are unsuitable for analyzing real-world clinical data. Therefore, none of the reported models have been widely used in routine clinical practice. To date, BN modeling analysis is a prominent and increasingly popular machine learning method that is powerful in dealing with dynamic and complex real-world data. STUDY DESIGN, SIZE, DURATION: A retrospective study was performed with 106,640 fresh embryo IVF/ICSI cycles from 2009 to 2019 in one of China's largest reproductive health centers. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 106, 640 cycles were included in this study, including 97,102 controls, 4,339 LFR cases, and 5,199 TFF cases. Twenty-four predictors were initially included, including 13 female-related variables, five male-related variables, and six variables related to IVF/ICSI treatment. BN modeling analysis with tenfold cross-validation was performed to construct the predictive model for TFF/LFR. The receiver operating characteristic (ROC) curves and the corresponding area under the curves (AUCs) were used to evaluate the performance of the BN model. MAIN RESULTS AND THE ROLE OF CHANCE: All twenty-four predictors were first organized into seven hierarchical layers in a theoretical BN model, according to prior knowledge from previous literature and clinical practice. A machine-learning BN model was generated based on real-world clinical data, containing a total of eighteen predictors, of which the infertility type, ART method, and number of retrieved oocytes directly influence the probabilities of LFR/TFF. The prediction accuracy of the BN model was 91.7%. The AUC of the TFF versus control groups was 0.779 (95% CI: 0.766-0.791), with a sensitivity of 71.2% and specificity of 70.1%; the AUC of of TFF versus LFR groups was 0.807 (95% CI: 0.790-0.824), with a sensitivity of 49.0% and specificity of 99.0%. LIMITATIONS, REASON FOR CAUTION: First, our study was based on clinical data from a single center, and the results of this study should be further verified by external data. In addition, some critical data (e.g., the detailed IVF laboratory parameters of the sperm and oocytes used for insemination) were not available in this study, which should be given full consideration when further improving the performance of the BN model. WIDER IMPLICATIONS OF THE FINDINGS: Based on extensive clinical real-world data, we developed a BN model to predict the probabilities of fertilization failures in ART, which provides new clues for clinical decision-making support for clinicians in formulating personalized treatment plans and further improving ART treatment outcomes. STUDY FUNDING/COMPETING INTEREST(S): Dr. Y. Wang was supported by grants from the Beijing Municipal Science & Technology Commission (Z191100006619086). We declare that there are no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Fertilização in vitro , Sêmen , Masculino , Feminino , Gravidez , Humanos , Estudos Retrospectivos , Teorema de Bayes , Fertilização in vitro/métodos , Técnicas de Reprodução Assistida , Fertilização , Taxa de Gravidez
3.
J Environ Manage ; 325(Pt A): 116534, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36419282

RESUMO

Long-term continuous hourly measurements of ambient volatile organic compounds (VOCs) are scarce at the regional scale. In this study, a one-year hourly measurement campaign of VOCs was performed in Lvliang, Linfen, and Yuncheng in the heavily polluted Fenhe Plain region in China. The VOC average (±standard deviation, std) concentrations in Lvliang, Linfen, and Yuncheng were 44.4 ± 24.9, 45.7 ± 24.9, and 37.5 ± 25.0 ppbv, respectively. Compared to published data from the past two decades in China, the observed VOCs were at high concentration levels. VOCs in the Fenhe Plain cities were significantly impacted by industrial sources according to calculated emission ratios but were less affected by liquefied petroleum gas and natural gas (LPG/NG) and traffic emissions than those in megacities abroad. The emission inventories and observation data were combined for verification and identification of the key VOC species and sources controlling ozone (O3). Industrial emissions were the largest source of VOCs, accounting for 65%-79% of the total VOC emissions, while the coking industry accounted for 45.2%-66.0%. The emission inventories significantly underestimated oxygenated VOC (OVOC) emissions through the verification of VOC emission ratios. O3 control scenarios were analyzed by changing VOC/NOX reduction ratios through a photochemical box model. O3 control strategies were formulated considering local pollution control plans, emission inventories, and O3 formation regimes. The O3 reduction of reactivity-control measures was comparable with emission-control measures, ranging from 16% to 41%, which was contrary to the general perception that ozone formation potential (OFP)-based measures were more efficient for O3 reduction. Sources with high VOC emissions are accompanied by high OFP on the Fenhe Plain, indicating that the control of high-emission sources can effectively mitigate O3 pollution on this region.


Assuntos
Ozônio , Compostos Orgânicos Voláteis , Cidades , China , Poluição Ambiental
4.
PLoS Comput Biol ; 18(12): e1010078, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36455043

RESUMO

The transmission heterogeneity of an epidemic is associated with a complex mixture of host, pathogen and environmental factors. And it may indicate superspreading events to reduce the efficiency of population-level control measures and to sustain the epidemic over a larger scale and a longer duration. Methods have been proposed to identify significant transmission heterogeneity in historic epidemics based on several data sources, such as contact history, viral genomes and spatial information, which may not be available, and more importantly ignore the temporal trend of transmission heterogeneity. Here we attempted to establish a convenient method to estimate real-time heterogeneity over an epidemic. Within the branching process framework, we introduced an instant-individualheterogenous infectiousness model to jointly characterize the variation in infectiousness both between individuals and among different times. With this model, we could simultaneously estimate the transmission heterogeneity and the reproduction number from incidence time series. We validated the model with data of both simulated and real outbreaks. Our estimates of the overall and real-time heterogeneities of the six epidemics were consistent with those presented in the literature. Additionally, our model is robust to the ubiquitous bias of under-reporting and misspecification of serial interval. By analyzing recent data from South Africa, we found evidence that the Omicron might be of more significant transmission heterogeneity than Delta. Our model based on incidence data was proved to be reliable in estimating the real-time transmission heterogeneity.


Assuntos
Epidemias , Humanos , Incidência , Surtos de Doenças , África do Sul/epidemiologia
5.
Vaccines (Basel) ; 10(4)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35455246

RESUMO

Omicron, the latest SARS-CoV-2 Variant of Concern (VOC), first appeared in Africa in November 2021. At present, the question of whether a new VOC will out-compete the currently predominant variant is important for governments seeking to determine if current surveillance strategies and responses are appropriate and reasonable. Based on both virus genomes and daily-confirmed cases, we compare the additive differences in growth rates and reproductive numbers (R0) between VOCs and their predominant variants through a Bayesian framework and phylo-dynamics analysis. Faced with different variants, we evaluate the effects of current policies and vaccinations against VOCs and predominant variants. The model also predicts the date on which a VOC may become dominant based on simulation and real data in the early stage. The results suggest that the overall additive difference in growth rates of B.1.617.2 and predominant variants was 0.44 (95% confidence interval, 95% CI: -0.38, 1.25) in February 2021, and that the VOC had a relatively high R0. The additive difference in the growth rate of BA.1 in the United Kingdom was 6.82 times the difference between Delta and Alpha, and the model successfully predicted the dominating process of Alpha, Delta and Omicron. Current vaccination strategies remain similarly effective against Delta compared to the previous variants. Our model proposes a reliable Bayesian framework to predict the spread trends of VOCs based on early-stage data, and evaluates the effects of public health policies, which may help us better prepare for the upcoming Omicron variant, which is now spreading at an unprecedented speed.

6.
Biosaf Health ; 4(1): 1-5, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34977529

RESUMO

Although significant achievements have shown that the coronavirus disease 2019 (COVID-19) resurgence in Beijing, China, was initiated by contaminated frozen products and transported via cold chain transportation, international travelers with asymptomatic symptoms or false-negative nucleic acid may have another possible transmission mode that spread the virus to Beijing. One of the key differences between these two assumptions was whether the virus actively replicated since, so far, no reports showed viruses could stop evolution in alive hosts. We studied severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequences in this outbreak by a modified leaf-dating method with the Bayes factor. The numbers of single nucleotide variants (SNVs) found in SARS-CoV-2 sequences were significantly lower than those called from B.1.1 records collected at the matching time worldwide (P = 0.047). In addition, results of the leaf-dating method showed ages of viruses sampled from this outbreak were earlier than their recorded dates of collection (Bayes factors > 10), while control sequences (selected randomly with ten replicates) showed no differences in their collection dates (Bayes factors < 10). Our results which indicated that the re-emergence of SARS-CoV-2 in Beijing in June 2020 was caused by a virus that exhibited a lack of evolutionary changes compared to viruses collected at the corresponding time, provided evolutionary evidence to the contaminated imported frozen food should be responsible for the reappearance of COVID-19 cases in Beijing. The method developed here might also be helpful to provide the very first clues for potential sources of COVID-19 cases in the future.

7.
BMC Med Genomics ; 14(1): 257, 2021 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-34717601

RESUMO

BACKGROUND: Type 2 Diabetes (T2D) is the result of a combination of genes and environment. The identified genetic loci can only explain part of T2D risk. Our study is aimed to explore the association between CTNNA3 single nucleotide polymorphisms (SNPs) and T2D risk. METHODS: We conducted a 'case-control' study among 1002 Chinese Han participants. Four candidate SNPs of CTNNA3 were selected (rs10822745 C/T, rs7920624 A/T, rs2441727 A/G, rs7914287 A/G), and logistic regression analysis was used to evaluate the association between candidate SNPs and T2D risk. We used single factor analysis of variance to analyze the differences of clinical characteristics among different genotypes. In this study, haplotype analysis was conducted by plink1.07 and Haploview software and linkage disequilibrium (LD) was calculated. The interaction of candidate SNPs in T2D risk was evaluated by multi-factor dimensionality reduction (MDR). Finally, we conducted a false-positive report probability (FPRP) analysis to detect whether the significant findings were just chance or noteworthy observations. RESULTS: The results showed that CTNNA3-rs7914287 was a risk factor for T2D ('T': OR = 1.33, p = 0.003; 'TT': OR = 2.21, p = 0.001; 'TT' (recessive): OR = 2.09, p = 0.001; Log-additive: OR = 1.34, p = 0.003). The results of subgroup analysis showed that rs7914287 was significantly associated with the increased risk of T2D among participants who were older than 60 years, males, smoking, drinking, or BMI > 24. We also found that rs2441727 was associated with reducing the T2D risk among participants who were older than 60 years, smoking, or drinking. In addition, rs7914287 was associated with T2D patients with no retinal degeneration; rs10822745 and rs7920624 were associated with the course of T2D patients. High density lipoprotein levels had significant differences under different genotypes of rs10822745. Under the different genotypes of rs7914287, the levels of aspartate aminotransferase, alanine aminotransferase and gamma-glutamyltransferase were also significantly different. CONCLUSION: We found that CTNNA3 genetic polymorphisms can be used as a new genetic signal of T2D risk in Chinese Han population. Especially, CTNNA3-rs7914287 showed an outstanding and significant association with T2D risk in both overall analysis and subgroup analysis.


Assuntos
Diabetes Mellitus Tipo 2/genética , Etnicidade/genética , Polimorfismo de Nucleotídeo Único , alfa Catenina/genética , Estudos de Casos e Controles , China , Diabetes Mellitus Tipo 2/etnologia , Humanos
8.
JAMA Netw Open ; 4(9): e2123634, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34505887

RESUMO

Importance: Twin pregnancy is a common occurrence in pregnancies conceived with in vitro fertilization (IVF), but the absolute risk of adverse obstetric outcomes stratified by IVF, twin or singleton pregnancy, and maternal age are unknown. Objective: To estimate the absolute risk of adverse obstetric outcomes at each maternal age among twin pregnancies conceived with IVF. Design, Setting, and Participants: This retrospective cohort study included pregnant women with infants born from January 1, 2013, to December 31, 2018, based on the Hospital Quality Monitoring System in China. Data were analyzed from September 1, 2020, to June 30, 2021. Exposures: Twin pregnancy with IVF (IVF-T), singleton pregnancy with IVF (IVF-S), twin pregnancy with non-IVF (nIVF-T), and singleton pregnancy with non-IVF (nIVF-S). Main Outcomes and Measures: Sixteen obstetric outcomes, including 10 maternal complications (gestational hypertension, eclampsia and preeclampsia, gestational diabetes, placenta previa, placental abruption, placenta accreta, preterm birth, dystocia, cesarean delivery, and postpartum hemorrhage) and 6 neonatal complications (fetal growth restriction, low birth weight, very low birth weight, macrosomia, malformation, and stillbirth). Results: Among 16 879 728 pregnant women aged 20 to 49 years (mean [SD] age, 29.2 [4.7] years), the twin-pregnancy rates were 32.1% in the IVF group and 1.5% in the non-IVF group (relative risk, 20.8; 95% CI, 20.6-20.9). The most common adverse obstetric outcomes after pregnancy conceived with IVF were cesarean delivery (88.8%), low birth weight (43.8%), preterm birth (39.6%), gestational diabetes (20.5%), gestational hypertension and preeclampsia and eclampsia (17.5%), dystocia (16.8%), and postpartum hemorrhage (11.9%). The absolute risk of most adverse obstetric outcomes in each subgroup presented in 2 dominant patterns: Pattern A indicated the absolute risk ranging from IVF-T to nIVF-T to IVF-S to nIVF-S, and pattern B indicated the absolute risk ranging from IVF-T to IVF-S to nIVF-T to nIVF-S. Both patterns showed an elevated obstetric risk with increasing maternal age in each subgroup. Conclusions and Relevance: In this cohort study, twin pregnancy, IVF, and advanced maternal age were independently associated with adverse obstetric outcomes. Given these findings, promotion of the elective single embryo transfer strategy is needed to reduce multiple pregnancies following IVF technologies. Unnecessary cesarean delivery shouldh be avoided in all pregnant women.


Assuntos
Fertilização in vitro , Idade Materna , Complicações na Gravidez/epidemiologia , Gravidez de Gêmeos , Adulto , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez/etiologia , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
9.
BMC Pulm Med ; 21(1): 213, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34233676

RESUMO

OBJECTIVE: Chronic obstructive pulmonary disease (COPD) is a complicated multi-factor, multi-gene disease. Here, we aimed to assess the association of genetic polymorphisms in LINC01414/ LINC00824 and interactions with COPD susceptibility. METHODS: Three single nucleotide polymorphisms (SNPs) in LINC01414/LINC00824 was genotyped by Agena MassARRAY platform among 315 COPD patients and 314 controls. Logistic analysis adjusted by age and gender were applied to estimate the genetic contribution of selected SNPs to COPD susceptibility. RESULTS: LINC01414 rs699467 (OR = 0.73, 95% CI 0.56-0.94, p = 0.015) and LINC00824 rs7815944 (OR = 0.56, 95% CI 0.31-0.99, p = 0.046) might be protective factors for COPD occurrence, while LINC01414 rs298207 (OR = 2.88, 95% CI 1.31-6.31, p = 0.008) risk-allele was related to the increased risk of COPD in the whole population. Rs7815944 was associated with the reduced risk of COPD in the subjects aged > 70 years (OR = 0.29, p = 0.005). Rs6994670 (OR = 0.57, p = 0.007) contribute to a reduced COPD risk, while rs298207 (OR = 7.94, p = 0.009) was related to a higher susceptibility to COPD at age ≤ 70 years. Rs298207 (OR = 2.54, p = 0.043) and rs7815944 (OR = 0.43, p = 0.028) variants was associated COPD risk among males. Rs7815944 (OR = 0.16, p = 0.031) was related to the reduced susceptibility of COPD in former smokers. Moreover, the association between rs298207 genotype and COPD patients with dyspnea was found (OR = 0.50, p = 0.016), and rs7815944 was related to COPD patients with wheezing (OR = 0.22, p = 0.008). CONCLUSION: Our finding provided further insights into LINC01414/LINC00824 polymorphisms at risk of COPD occurrence and accumulated evidence for the genetic susceptibility of COPD.


Assuntos
Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/genética , RNA Longo não Codificante/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , China , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade
10.
Artigo em Inglês | MEDLINE | ID: mdl-34068947

RESUMO

Few studies have examined the transmission dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in rural areas and clarified rural-urban differences. Moreover, the effectiveness of non-pharmaceutical interventions (NPIs) relative to vaccination in rural areas is uncertain. We addressed this knowledge gap through using an improved statistical stochastic method based on the Galton-Watson branching process, considering both symptomatic and asymptomatic cases. Data included 1136 SARS-2-CoV infections of the rural outbreak in Hebei, China, and 135 infections of the urban outbreak in Tianjin, China. We reconstructed SARS-CoV-2 transmission chains and analyzed the effectiveness of vaccination and NPIs by simulation studies. The transmission of SARS-CoV-2 showed strong heterogeneity in urban and rural areas, with the dispersion parameters k = 0.14 and 0.35, respectively (k < 1 indicating strong heterogeneity). Although age group and contact-type distributions significantly differed between urban and rural areas, the average reproductive number (R) and k did not. Further, simulation results based on pre-control parameters (R = 0.81, k = 0.27) showed that in the vaccination scenario (80% efficacy and 55% coverage), the cumulative secondary infections will be reduced by more than half; however, NPIs are more effective than vaccinating 65% of the population. These findings could inform government policies regarding vaccination and NPIs in rural and urban areas.


Assuntos
COVID-19 , SARS-CoV-2 , China/epidemiologia , Simulação por Computador , Surtos de Doenças , Humanos
11.
PLoS Comput Biol ; 16(9): e1008122, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32881984

RESUMO

Spread of HIV typically involves uneven transmission patterns where some individuals spread to a large number of individuals while others to only a few or none. Such transmission heterogeneity can impact how fast and how much an epidemic spreads. Further, more efficient interventions may be achieved by taking such transmission heterogeneity into account. To address these issues, we developed two phylogenetic methods based on virus sequence data: 1) to generally detect if significant transmission heterogeneity is present, and 2) to pinpoint where in a phylogeny high-level spread is occurring. We derive inference procedures to estimate model parameters, including the amount of transmission heterogeneity, in a sampled epidemic. We show that it is possible to detect transmission heterogeneity under a wide range of simulated situations, including incomplete sampling, varying levels of heterogeneity, and including within-host genetic diversity. When evaluating real HIV-1 data from different epidemic scenarios, we found a lower level of transmission heterogeneity in slowly spreading situations and a higher level of heterogeneity in data that included a rapid outbreak, while R0 and Sackin's index (overall tree shape statistic) were similar in the two scenarios, suggesting that our new method is able to detect transmission heterogeneity in real data. We then show by simulations that targeted prevention, where we pinpoint high-level spread using a coalescence measurement, is efficient when sequence data are collected in an ongoing surveillance system. Such phylogeny-guided prevention is efficient under both single-step contact tracing as well as iterative contact tracing as compared to random intervention.


Assuntos
Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , HIV-1/classificação , HIV-1/genética , Algoritmos , Biologia Computacional , Simulação por Computador , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Humanos , Filogenia
12.
Artigo em Inglês | MEDLINE | ID: mdl-32456346

RESUMO

COVID-19 caused rapid mass infection worldwide. Understanding its transmission characteristics, including heterogeneity and the emergence of super spreading events (SSEs) where certain individuals infect large numbers of secondary cases, is of vital importance for prediction and intervention of future epidemics. Here, we collected information of all infected cases (135 cases) between 21 January and 26 February 2020 from official public sources in Tianjin, a metropolis of China, and grouped them into 43 transmission chains with the largest chain of 45 cases and the longest chain of four generations. Utilizing a heterogeneous transmission model based on branching process along with a negative binomial offspring distribution, we estimated the reproductive number R and the dispersion parameter k (lower value indicating higher heterogeneity) to be 0.67 (95% CI: 0.54-0.84) and 0.25 (95% CI: 0.13-0.88), respectively. A super-spreader causing six infections was identified in Tianjin. In addition, our simulation allowing for heterogeneity showed that the outbreak in Tianjin would have caused 165 infections and sustained for 7.56 generations on average if no control measures had been taken by local government since 28 January. Our results highlighted more efforts are needed to verify the transmission heterogeneity of COVID-19 in other populations and its contributing factors.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Pneumonia Viral/transmissão , COVID-19 , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Surtos de Doenças , Humanos , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , SARS-CoV-2
13.
Clin Exp Pharmacol Physiol ; 46(4): 398-403, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30570785

RESUMO

The study introduced a homogeneous orthogonal diffusion model to describe the diffusion pattern of agents in the rat brain. Magnetic resonance imaging was performed post-injection of paramagnetic drugs into the caudatum of the rat brain at predetermined time intervals. The signal intensity on magnetic resonance images was converted to agents' concentration, and the standard least square method was employed to estimate the diffusion coefficients. The diffusion coefficients calculated along the three orthogonal axes were D1  = (0.0097 ± 0.0036) mm2 /h, D2  = (0.0153 ± 0.0033) mm2 /h, and D3  = (0.0293 ± 0.0155) mm2 /h; the clearance rate constant was k = (0.2177 ± 0.0112)/h. The theoretical homogeneous orthogonal model can enhance our knowledge on both the biophysical characteristics of brain extracellular space and the interstitial drug delivery in the brain.

14.
Wei Sheng Yan Jiu ; 47(3): 395-398, 2018 May.
Artigo em Chinês | MEDLINE | ID: mdl-30082005

RESUMO

OBJECTIVE: To investigate the prevalence of central obesity among different gender and age groups of floating population employment in 5 surveillance sites of Xinjiang Uygur Autonomous Region. METHODS: 1491 floating population aged > 18 years old were selected through multistage clustering sampling method, stratified by 6 major industries in5 sites of Xinjiang Uygur Autonomous Region( Xinhe County, Yining County, Tianshan District, Hetian County and Kashi City) in 2012. Unified questionnaire( including basic information, behavioral risk factors, etc. ), designed by China CDC, were used to collect information by face-to-face interviews. Height, weight and waist circumference were measured by unified equipment. RESULTS: The average age was( 35. 73 ± 11. 61) years old. Male and female accounted for 48. 02%( 716/1491) and 51. 98%( 775/1491)each. Han, Uygur and other ethnic group accounted for 75. 59%( 1127/1491), 18. 31%( 273/1491) and 6. 10%( 91/1491). The prevalence of central obesity was 25. 62%( 382/1491) of floating population in 5 surveillance sites of Xinjiang Uygur Autonomous Region, 50-59 years age group( 45. 63%) and the obese group( 86. 15%) in BMI were the highest prevalence of central obesity. There was statistical significance on prevalence of central obesity in different age groups floating population( χ~2= 77. 295, P <0. 001), and in different BMI groups floating population( χ~2= 648. 619, P < 0. 001). CONCLUSION: Floating population aged 50-59 years old and obese in BMI of Xinjiang Uygur Autonomous Region were key groups for prevention and control of central obesity.


Assuntos
Povo Asiático/estatística & dados numéricos , Emprego , Obesidade Abdominal/epidemiologia , Vigilância da População , Adolescente , Criança , China , Etnicidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade , Prevalência , Fatores de Risco
15.
Radiat Oncol ; 10: 28, 2015 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-25623899

RESUMO

PURPOSE: To compare the dosimetric differences between jaw tracking technique (JTT) and static jaw technique (SJT) in dynamic intensity-modulated radiotherapy (d-IMRT) and assess the potential advantages of jaw tracking technique. METHODS: Two techniques, jaw tracking and static jaw, were used respectively to develop the d-IMRT plans for 28 cancer patients with various lesion sites: head and neck, lungs, esophageal, abdominal, prostate, rectal and cervical. The dose volume histograms (DVH) and selected dosimetric indexes for the whole body and for organs at risk (OARs) were compared. A two dimensional ionization chamber Array Seven29 (PTW, Freiburg, Germany) and OCTAVIUS Octagonal phantom (PTW, Freiburg, Germany) were used to verify all the plans. RESULTS: For all patients, the treatment plans using both techniques met the clinical requirements. The V5, V10, V20, V30, V40 (volumes receiving 5, 10, 20, 30 and 40 Gy at least, respectively), mean dose (Dmean) for the whole body and V5, V10, V20, Dmean for lungs in the JTT d-IMRT plans were significantly less than the corresponding values of the SJT d-IMRT plans (p < 0.001). The JTT d-IMRT plans deposited lower maximum dose (Dmax) to the lens, eyes, brainstem, spinal cord, and right optic nerve, the doses reductions for these OARs ranged from 2.2% to 28.6%. The JTT d-IMRT plans deposited significantly lower Dmean to various OARs (all p values < 0.05), the mean doses reductions for these OARs ranged from 1.1% to 31.0%, and the value reductions depend on the volume and the location of the OARs. The γ evaluation method showed an excellent agreement between calculation and measurement for all techniques with criteria of 3%/3 mm. CONCLUSIONS: Both jaw tracking and static jaw d-IMRT plans can achieve comparable target dose coverage. JTT displays superior OARs sparing than SJT plans. These results are of clinical importance, especially for the patients with large and complex targets but close to some highly radio-sensitive organs to spare, and for patients with local recurrent or secondary primary malignant lesion within a previously irradiated area.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Registro da Relação Maxilomandibular/métodos , Arcada Osseodentária/efeitos da radiação , Neoplasias/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Arcada Osseodentária/fisiologia , Registro da Relação Maxilomandibular/instrumentação , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Órgãos em Risco/efeitos da radiação , Radiometria/métodos , Dosagem Radioterapêutica , Estudos Retrospectivos
16.
J Theor Biol ; 353: 170-8, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-24631047

RESUMO

Reliable functioning is crucial for the survival and development of the genetic regulatory networks in living cells and organisms. This functional reliability is an important feature of the networks and reflects the structural features that have been embedded in the regulatory networks by evolution. In this paper, we integrate this reliability into network reconstruction. We introduce the concept of dependency probability to measure the dependency of functional reliability on network edges. We also propose a method to estimate the dependency probability and select edges with high contributions to functional reliability. We use two real examples, the regulatory network of the cell cycle of the budding yeast and that of the fission yeast, to demonstrate that the proposed method improves network reconstruction. In addition, the dependency probability is robust in calculation and can be easily implemented in practice.


Assuntos
Redes Reguladoras de Genes , Saccharomycetales/genética , Schizosaccharomyces/genética , Ciclo Celular/genética , Modelos Genéticos , Probabilidade , Reprodutibilidade dos Testes , Saccharomycetales/citologia , Schizosaccharomyces/citologia
17.
Asian Pac J Trop Med ; 4(8): 594-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21914533

RESUMO

Hainan is an island province in south China with a high frequency of unconventional emergencies due to its special geographic location and national military defense role. Given the limited transportation route from Hainan to the outside world, self-rescue is more important to Hainan Province than other provinces in China and it is therefore imperative to establish an independent, scientific as well as efficient provincal disaster medical system in Hainan. The regulatory role for vulnerability analysis/assessment has been demonstrated in establisment of disaster medical system in varoius countries and or regions. In this paper, we attempt to describe/propose how to adopt vulnerability assessment through mathematical modeling of major biophysical social vulnerability factors to establish an independent, scientific, effieicnt and comprehensive provincial disaster medical system in Hainan.


Assuntos
Defesa Civil/organização & administração , Planejamento em Desastres/organização & administração , Serviços Médicos de Emergência/organização & administração , China , Defesa Civil/métodos , Planejamento em Desastres/métodos , Desastres , Serviços Médicos de Emergência/métodos , Geografia , Humanos , Modelos Organizacionais
18.
Opt Express ; 17(15): 12582-7, 2009 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-19654661

RESUMO

Continuous-wave (cw) laser action around 2 microm in Ho(3+)-doped Lu(2)SiO(5) (LSO) was demonstrated in this paper. Cryogenically cooled by liquid nitrogen, a 10-mm long Tm-sensitized (6% at.) Ho(0.4% at.):LSO produced a maximum output power of 3 W at 2.07 microm for incident diode power of 11 W at 786 nm, and a slope efficiency of 35% with respect to incident pump power. To achieve room-temperature operation of Tm, Ho:LSO laser, a 1-mm long microchip crystal was pumped by a high brightness diode, generating an output power of greater than 80 mW and a slope efficiency of 26% at 2.08 microm. Using a 1.91 microm Tm:YLF laser as an in-band pump source, room-temperature cw operation of singly-doped Ho: Lu(2)SiO(5) laser at 2106 nm was attained with a maximum output power of 2.8 W and a slope efficiency of 35% corresponding to absorbed pump power.

19.
Opt Lett ; 33(18): 2161-3, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18794964

RESUMO

Single-frequency output power of 7.3 W at 2.09 mum from a monolithic Ho:YAG nonplanar ring oscillator (NPRO) is demonstrated. Resonantly pumped by a Tm-doped fiber laser at 1.91 mum, the Ho:YAG NPRO produces 71% of slope efficiency with respect to absorbed pump power and nearly diffraction-limited output with a beam quality parameter of M(2) approximately 1.1.

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