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1.
J Voice ; 37(2): 300.e11-300.e20, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33495036

RESUMO

BACKGROUND AND OBJECTIVE: In smoking cessation clinical research and practice, objective validation of self-reported smoking status is crucial for ensuring the reliability of the primary outcome, that is, smoking abstinence. Speech signals convey important information about a speaker, such as age, gender, body size, emotional state, and health state. We investigated (1) if smoking could measurably alter voice features, (2) if smoking cessation could lead to changes in voice, and therefore (3) if the voice-based smoking status assessment has the potential to be used as an objective smoking cessation validation method. METHODS: A systematic review of the scientific literature was conducted to compile studies on smoking status assessment based on voice features. We searched nine scientific databases for original studies involving the effects of smoking on voice features, the effects of smoking cessation on voice features. RESULTS: A total of 34 studies were identified for review. We found that fundamental frequency, jitter, shimmer, harmonics to noise ratio, and other voice features are affected by smoking and could be used to assess smoking status. CONCLUSION: Speech assessment of smoking status based on voice features has potential as a smoking status validation method, as it is simple, reliable, and less time-consuming. Furthermore, this study provides recommendations for future research on the objective speech assessment of smoking status based on voice features.


Assuntos
Fala , Qualidade da Voz , Humanos , Fumar , Reprodutibilidade dos Testes , Acústica da Fala
2.
New Phytol ; 234(5): 1639-1653, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35243647

RESUMO

The root economics space (RES) is multidimensional and largely shaped by belowground biotic and abiotic influences. However, how root-fungal symbioses and edaphic fertility drive this complexity remains unclear. Here, we measured absorptive root traits of 112 tree species in temperate and subtropical forests of China, including traits linked to functional differences between arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) hosts. Our data, from known mycorrhizal tree species, revealed a 'fungal-symbiosis' dimension distinguishing AM from ECM species. This divergence likely resulted from the contrasting mycorrhizal evolutionary development of AM vs ECM associations. Increased root tissue cortical space facilitates AM symbiosis, whereas increased root branching favours ECM symbiosis. Irrespective of mycorrhizal type, a 'root-lifespan' dimension reflecting aspects of root construction cost and defence was controlled by variation in specific root length and root tissue density, which was fully independent of root nitrogen content. Within this function-based RES, we observed a substantial covariation of axes with soil phosphorus and nitrate levels, highlighting the role played by these two axes in nutrient acquisition and conservation. Overall, our findings demonstrate the importance of evolved mycorrhizal symbiosis pathway and edaphic fertility in framing the RES, and provide theoretical and mechanistic insights into the complexity of root economics.


Assuntos
Micorrizas , Fertilidade , Raízes de Plantas/metabolismo , Solo , Microbiologia do Solo , Simbiose , Árvores
4.
PLoS One ; 16(10): e0258524, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34648573

RESUMO

With social and economic environment changes occurring in the world and deepening of the urbanization process, China's urban development exhibits a new phenomenon of growth and shrinkage fluctuations. The resource-based city shrinkage phenomenon is particularly prominent. Research on the commonalities and patterns of similar groups should be enhanced. We constructed an urban shrinkage evaluation index system from the three dimensions of population, economy and space. Accordingly, we explored the spatiotemporal evolution characteristics of 175 resource-based cities in China from a multidimensional perspective with the entropy method, shrinkage model and transfer matrix method. The results indicated that most resource-based cities in China occurred in the non-shrinking state, but their development speed gradually decreased or even presented stagflation. The shrinkage measure-related results in the different dimensions revealed that the number of shrinking cities is increasing. The population, economic and comprehensive shrinkage levels were mainly slight and remained stable. The number of cities experiencing moderate and severe shrinkage was relatively small and mostly encompassed short-term shrinkage. Spatial shrinkage demonstrated a clear administrative hierarchy difference. Moreover, the spatial distribution range of shrinking cities in each dimension expanded and exhibited obviously similar characteristics, i.e., shrinking cities were relatively concentrated in Northeast China, while they were more scattered in other regions. Furthermore, the geodetector technique was applied to reveal the influencing factors of resource-based city growth and shrinkage. Based on the results, the change in the secondary industry output value share at the start of the study was the primary factor. The impact of each employment structure indicator from 2014 to 2018 was particularly significant. Comprehensive exploration of the shrinkage characteristics of this particular group of cities and their development behavior from a multidimensional perspective can provide an important reference for the transformation and high-quality development of resource-based cities.


Assuntos
Reforma Urbana , China , Cidades , Humanos , Dinâmica Populacional , Análise Espaço-Temporal
5.
Nat Commun ; 10(1): 2203, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101818

RESUMO

The root economics spectrum (RES), a common hypothesis postulating a tradeoff between resource acquisition and conservation traits, is being challenged by conflicting relationships between root diameter, tissue density (RTD) and root nitrogen concentration (RN). Here, we analyze a global trait dataset of absorptive roots for over 800 plant species. For woody species (but not for non-woody species), we find nonlinear relationships between root diameter and RTD and RN, which stem from the allometric relationship between stele and cortical tissues. These nonlinear relationships explain how sampling bias from different ends of the nonlinear curves can result in conflicting trait relationships. Further, the shape of the relationships varies depending on evolutionary context and mycorrhizal affiliation. Importantly, the observed nonlinear trait relationships do not support the RES predictions. Allometry-based nonlinearity of root trait relationships improves our understanding of the ecology, physiology and evolution of absorptive roots.


Assuntos
Evolução Biológica , Raízes de Plantas/genética , Plantas/genética , Característica Quantitativa Herdável , Conjuntos de Dados como Assunto , Dinâmica não Linear , Fenótipo , Filogenia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/metabolismo , Plantas/anatomia & histologia , Plantas/metabolismo
6.
Artigo em Chinês | MEDLINE | ID: mdl-26541036

RESUMO

OBJECTIVE: To investigate the antimalarial activity of four choline derivatives against Plasmodium falciparum 3D7 strain growth in vitro. METHODS: Four choline derivatives MD [N-dodecyl-N-(2-hydroxyethyl)-N,N- dimethyl ammonium bromide], ED [N-dodecyl-N-(2-hydroxyethyl)-N,N-diethyl ammonium bromide], MT [N-tetradecyl-N- (2-hydroxyethyl)-N,N-dimethyl ammonium bromide], and ET [N-tetradecyl-N-(2-hydroxyethyl)-N,N-diethyl ammonium bromide] were dissolved separately in DMSO at serial concentrations (1-10(5) µmol/L). The solutions were diluted by 1,000-fold with RPMI 1640 medium. 20 µl drug-containing medium and 80 µl P. falciparum-infected erythrocyte suspension (2% final hematocrit and 0.3%-0.5% parasitemia) were added to each well of microtiter plates. Drug effect on the in vitro growth of P. falciparum was measured by SYBR Green I method. The half maximal inhibitory concentration (IC50) was calculated from dose-response curves. Artemisinine served as positive control. RESULTS: Artemisinine, MD, ED, MT, and ET showed different degrees of dose-dependent inhibition on P. falciparum growth. When the MD concentration was above 10 nmol/L, the inhibition rate increased significantly. Both ED and ET showed significant inhibitory effects at high concentrations, with inhibition rate of > 95% when their doses were > 10(4) nmol/L. The IC50 values of MD, ED, MT, and ET were 1 620, 33.9, 116, and 68.9 nmol/L, respectively, all significantly higher than that of artemisinine (5.7 nmol/L) (P < 0.05). CONCLUSION: The four choline derivatives show certain antimalarial activity, which is lower than that of artemisinine. Among the four derivatives, ED has the strongest antimalarial activity against P. falciparum 3D7 strain.


Assuntos
Plasmodium falciparum , Antimaláricos , Artemisininas , Benzotiazóis , Colina , Diaminas , Humanos , Malária Falciparum , Compostos Orgânicos , Quinolinas
7.
PLoS One ; 7(10): e47153, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23071740

RESUMO

BACKGROUND: Maternal deaths occur mostly in developing countries and the majority of them are preventable. This study analyzes changes in maternal mortality and related causes in Henan Province, China, between 1996 and 2009, in an attempt to provide a reliable basis for introducing effective interventions to reduce the maternal mortality ratio (MMR), part of the fifth Millennium Development Goal. METHODS AND FINDINGS: This population-based maternal mortality survey in Henan Province was carried out from 1996 to 2009. Basic information was obtained from the health care network for women and children and the vital statistics system, from specially trained monitoring personnel in 25 selected monitoring sites and by household survey in each case of maternal death. This data was subsequently reported to the Henan Provincial Maternal and Child Healthcare Hospital. The total MMR in Henan Province declined by 78.4%, from 80.1 per 100 000 live births in 1996 to 17.3 per 100 000 live births in 2009. The decline was more pronounced in rural than in urban areas. The most common causes of maternal death during this period were obstetric hemorrhage (43.8%), pregnancy-induced hypertension (15.8%), amniotic fluid embolism (13.9%) and heart disease (8.0%). The MMR was higher in rural areas with lower income, less education and poorer health care. CONCLUSION: There was a remarkable decrease in the MMR in Henan Province between 1996 and 2009 mainly in the rural areas and MMR due to direct obstetric causes such as obstetric hemorrhage. This study indicates that improving the health care network for women, training of obstetric staff at basic-level units, promoting maternal education, and increasing household income are important interventional strategies to reduce the MMR further.


Assuntos
Mortalidade Materna/tendências , Complicações na Gravidez/epidemiologia , China/epidemiologia , Feminino , Acessibilidade aos Serviços de Saúde/tendências , Humanos , Gravidez , Complicações na Gravidez/prevenção & controle , Saúde da População Rural , População Rural/tendências , População Urbana/tendências
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