Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Can Assoc Radiol J ; : 8465371241238917, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577746

RESUMO

PURPOSE: To assess the diagnostic utility of clinical magnetic resonance spectroscopy (MRS) and diffusion-weighted imaging (DWI) in distinguishing between histological grading and isocitrate dehydrogenase (IDH) classification in adult diffuse gliomas. METHODS: A retrospective analysis was conducted on 247 patients diagnosed with adult diffuse glioma. Experienced radiologists evaluated DWI and MRS images. The Kruskal-Wallis test examined differences in DWI and MRS-related parameters across histological grades, while the Mann-Whitney U test assessed molecular classification. Receiver Operating Characteristic (ROC) curves evaluated parameter effectiveness. Survival curves, stratified by histological grade and IDH classification, were constructed using the Kaplan-Meier test. RESULTS: The cohort comprised 141 males and 106 females, with ages ranging from 19 to 85 years. The Kruskal-Wallis test revealed significant differences in ADC mean, Cho/NAA, and Cho/Cr concerning glioma histological grade (P < .01). Subsequent application of Dunn's test showed significant differences in ADC mean among each histological grade (P < .01). Notably, Cho/NAA exhibited a marked distinction between grade 2 and grade 3/4 gliomas (P < .01). The Mann-Whitney U test indicated that only ADC mean showed statistical significance for IDH molecular classification (P < .01). ROC curves were constructed to demonstrate the effectiveness of the specified parameters. Survival curves were also delineated to portray survival outcomes categorized by histological grade and IDH classification. Conclusions: Clinical MRS demonstrates efficacy in glioma histological grading but faces challenges in IDH classification. Clinical DWI's ADC mean parameter shows significant distinctions in both histological grade and IDH classification.

2.
PLoS One ; 19(4): e0300245, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38568881

RESUMO

Recent labor market transformations brought on by digital and technological advances, together with the rise of the service economy since the 1980s, have subjected more workers to precarious conditions, such as irregular work hours and low or unpredictable wages, threatening their economic well-being and health. This study advances our understanding of the critical role employment plays in our health by examining how employment patterns throughout our working lives, based on work schedules, may shape our health at age 50, paying particular attention to the moderating role of social position. The National Longitudinal Survey of Youth-1979 (NLSY79), which has collected 30+ years of longitudinal information, was used to examine how employment patterns starting at ages 22 (n ≈ 7,336) might be associated with sleep hours and quality, physical and mental functions, and the likelihood of reporting poor health and depressive symptoms at age 50. Sequence analysis found five dominant employment patterns between ages 22 and 49: "mostly not working" (10%), "early standard hours before transitioning into mostly variable hours" (12%), "early standard hours before transitioning into volatile schedules" (early ST-volatile, 17%), "mostly standard hours with some variable hours" (35%), and "stable standard hours" (26%). The multiple regression analyses indicate that having the "early ST-volatile" schedule pattern between ages 22 and 49 was consistently, significantly associated with the poorest health, including the fewest hours of sleep per day, the lowest sleep quality, the lowest physical and mental functions, and the highest likelihood of reporting poor health and depressive symptoms at age 50. In addition, social position plays a significant role in these adverse health consequences. For example, whereas non-Hispanic White women reported the most hours of sleep and non-Hispanic Black men reported the fewest, the opposite was true for sleep quality. In addition, non-Hispanic Black men with less than a high school education had the highest likelihood of reporting poor health at age 50 if they engaged in an employment pattern of "early ST-volatile" between ages 22 and 49. In comparison, non-Hispanic White men with a college degree or above education had the lowest likelihood of reporting poor health if they engaged in an employment pattern of stable standard hours. This analysis underscores the critical role of employment patterns in shaping our daily routines, which matter to sleep and physical and mental health as we approach middle adulthood. Notably, the groups with relatively disadvantaged social positions are also likely to be subject to nonstandard work schedules, including non-Hispanic Blacks and people with low education; hence, they were more likely than others to shoulder the harmful links between nonstandard work schedules and sleep and health, worsening their probability of maintaining and nurturing their health as they approach middle adulthood.


Assuntos
Emprego , Admissão e Escalonamento de Pessoal , Masculino , Humanos , Feminino , Adulto , Adolescente , Pessoa de Meia-Idade , Estudos Longitudinais , Salários e Benefícios , Escolaridade
3.
Heart Rhythm ; 21(5): 600-609, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38266752

RESUMO

BACKGROUND: The motion relationship and time intervals of the pulsed-wave Doppler (PWD) spectrum are essential for diagnosing fetal arrhythmia. However, few technologies currently are available to automatically calculate fetal cardiac time intervals (CTIs). OBJECTIVE: The purpose of this study was to develop a fetal heart rhythm intelligent quantification system (HR-IQS) for the automatic extraction of CTIs and establish the normal reference range for fetal CTIs. METHODS: A total of 6498 PWD spectrums of 2630 fetuses over the junction between the left ventricular inflow and outflow tracts were recorded across 14 centers. E, A, and V waves were manually labeled by 3 experienced fetal cardiologists, with 17 CTIs extracted. Five-fold cross-validation was performed for training and testing of the deep learning model. Agreement between the manual and HR-IQS-based values was evaluated using the intraclass correlation coefficient and Spearman's rank correlation coefficient. The Jarque-Bera test was applied to evaluate the normality of CTIs' distributions, and the normal reference range of 17 CTIs was established with quantile regression. Arrhythmia subset was compared with the non-arrhythmia subset using the Mann-Whitney U test. RESULTS: Significant positive correlation (P <.001) and moderate-to-excellent consistency (P <.001) between the manual and HR-IQS automated measurements of CTIs was found. The distribution of CTIs was non-normal (P <.001). The normal range (2.5th to 97.5th percentiles) was successfully established for the 17 CTIs. CONCLUSIONS: Using our HR-IQS is feasible for the automated calculation of CTIs in practice and thus could provide a promising tool for the assessment of fetal rhythm and function.


Assuntos
Arritmias Cardíacas , Coração Fetal , Frequência Cardíaca Fetal , Humanos , Feminino , Estudos Prospectivos , Gravidez , Frequência Cardíaca Fetal/fisiologia , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Coração Fetal/diagnóstico por imagem , Coração Fetal/fisiologia , Idade Gestacional , Ultrassonografia Pré-Natal/métodos
4.
Huan Jing Ke Xue ; 44(9): 5253-5263, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699843

RESUMO

To study the sources and potential risks of heavy metals in soils of characteristic agricultural product producing areas is of great significance for the scientific management and safe utilization of soil and crop resources. The contents of heavy metals As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the 254 surface soil samples collected from the Heze oil peony planting area were determined. The content characteristics and correlation of heavy metals were analyzed using multivariate statistical methods. The sources of heavy metals in topsoil were analyzed using Igeo, PMF, and PCA/APCS. The ecological risks of the eight heavy metals were assessed through the potential ecological risk index (PERI). The results showed that the average contents of seven heavy metals in the soil were basically consistent with the background values of soil elements in Heze City, except that the average value of Cd was 1.44 times higher than the background value in Heze City. Correlation analysis and cluster analysis revealed that Pb, Hg, and Cd elements in the soil were greatly affected by human activities in the later period. The sources of eight heavy metals in the study area were natural sources, agricultural fertilizer sources, industrial coal sources, and domestic transportation sources, with the contribution rates of 81.31%, 15.45%, 2.74%, and 0.50%, respectively; 84.25% of the sites in the study area were at slight ecological risk, whereas the moderate risk and strong risk sites accounted for 14.96% and 0.79%, respectively. Among them, Cd and Hg were the dominant elements of ecological risk in the study area.

5.
Curr Med Imaging ; 19(9): 971-976, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36703588

RESUMO

Amide proton transfer (APT) imaging is a technique that reflects the level of amide proton transport of hydrogen ions in water to peptides and proteins within the tumour by using magnetic resonance imaging without contrast administration. This technique can more accurately reflect the protein level, pH value, and other relevant information within the tumour. Currently, APT is widely used in glioma research. In this paper, we briefly describe the research progress on this technique.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Prótons , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/metabolismo , Amidas , Glioma/diagnóstico por imagem , Glioma/cirurgia , Imageamento por Ressonância Magnética/métodos
6.
World J Clin Cases ; 10(24): 8568-8577, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36157801

RESUMO

BACKGROUND: Pancreatic segmental portal hypertension (PSPH) is the only type of portal hypertension that can be completely cured. However, it can easily cause varicose veins in the esophagus and stomach and hemorrhage in the digestive tract. AIM: To explore the application of computed tomography (CT) to examine the characteristics of PSPH and assess the risk level. METHODS: This was a retrospective analysis of CT images of 22 patients diagnosed with PSPH at our center. Spearman correlation analysis was performed using the range of esophageal and gastric varices (measured by the vertical gastric wall), the ratio of the width of the splenic portal vein to that of the compression site (S/C ratio), the degree of splenomegaly, and the stage determined by gastroscopy. This study examined whether patients experienced gastrointestinal bleeding within 2 wk and combined CT and gastroscopy to explore the connection between bleeding and CT findings. RESULTS: The range of esophageal and gastric varices showed the best correlation in the diagnosis of PSPH (P < 0.001), and the S/C ratio (P = 0.007) was correlated with the degree of splenomegaly (P = 0.021) and PSPH (P < 0.05). This study revealed that male patients were more likely than females to progress to grade 2 or grade 3 as determined by gastroscopy. CT demonstrated excellent performance, with an area under the curve of 0.879. CONCLUSION: CT can be used to effectively analyze the imaging signs of PSPH, and CT combined with gastroscopy can effectively predict the risk level of gastrointestinal bleeding.

7.
Soc Sci Q ; 102(5): 2394-2411, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34908614

RESUMO

OBJECTIVE: As labor markets in recent decades have become increasingly volatile and precarious, more workers are susceptible to working conditions threatening their economic security. COVID-19 has further laid bare such economic insecurity from holding a precarious job. We examined the association between precarious employment and the probability of losing income or a job during COVID-19 pandemic. METHODS: A multivariate regression analysis was conducted using a cross-sectional data set collected in May 2020 in the United States. RESULTS: Our results confirm a strong positive association between precarious employment and losing work or income. Specifically, holding part-time work in the service sector, and feeling disempowered in the workplace, receiving low material rewards, having few benefits, and experiencing obstacles in exercising rights all significantly doubled the probability of losing income or jobs. CONCLUSION: Our analysis underscores the increasing vulnerability faced by our workforce and how a public health crisis magnifies the dire consequences of a precarious job.

8.
Fam Process ; 59(3): 832-846, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32589267

RESUMO

The COVID-19 pandemic brings to the forefront the complex interconnected dilemmas of globalization, health equity, economic security, environmental justice, and collective trauma, severely impacting the marginalized and people of color in the United States. This lack of access to and the quality of healthcare, affordable housing, and lack of financial resources also continue to have a more significant impact on documented and undocumented immigrants. This paper aims at examining these critical issues and developing a framework for family therapists to address these challenges by focusing on four interrelated dimensions: cultural values, social determinants of health, collective trauma, and the ethical and moral responsibility of family therapists. Given the fact that family therapists may unwittingly function as the best ally of an economic and political system that perpetuates institutionalized racism and class discrimination, we need to utilize a set of principles, values, and practices that are not just palliative or after the fact but bring forth into the psychotherapeutic and policy work a politics of care. Therefore, a strong call to promote and advocate for the broader continuum of health and critical thinking preparing professionals to meet the challenges of health equity, as well as economic and environmental justice, is needed. The issues discussed in this paper are specific to the United States despite their relevance to family therapy as a field. We are mindful not to generalize the United States' reality to the rest of the world, recognizing that issues discussed in this paper could potentially contribute to international discourse.


La pandemia de la COVID-19 ha puesto en primer plano los dilemas complejos e interconectados de la globalización, la equidad sanitaria, la seguridad económica, la justicia ambiental y el trauma colectivo, afectando gravemente a las personas marginadas y de color de los Estados Unidos. Esta falta de acceso a asistencia sanitaria de calidad, a viviendas asequibles, y la falta de recursos económicos también continúan teniendo un efecto más significativo en los inmigrantes documentados e indocumentados. Este artículo tiene como finalidad analizar estas cuestiones críticas y desarrollar un marco para que los terapeutas familiares aborden estas dificultades centrándose en cuatro dimensiones interrelacionadas: valores culturales, determinantes sociales de salud, trauma colectivo, y responsabilidad ética y moral de los terapeutas familiares. Teniendo en cuenta el hecho de que los terapeutas familiares pueden funcionar inconscientemente como los mejores aliados de un sistema económico y político que perpetúa el racismo institucionalizado y el clasismo, necesitamos utilizar un conjunto de principios, valores y prácticas que no sea solo paliativo o a posteriori, sino que genere en el trabajo político y psicoterapéutico una política de asistencia. Por lo tanto, es necesario un reclamo firme de promover y abogar por un continuo más amplio de la salud y un pensamiento crítico que prepare a los profesionales para responder a las dificultades de la equidad sanitaria, así como de la justicia económica y ambiental, si fuera necesario. Las cuestiones tratadas en este artículo son específicas de los Estados Unidos a pesar de su relevancia para la terapia familiar como área. Somos conscientes de no generalizar la realidad de los Estados Unidos para el resto del mundo, y reconocemos que las cuestiones tratadas en este artículo podrían contribuir al discurso internacional.


Assuntos
Terapia Familiar/ética , Disparidades nos Níveis de Saúde , Pandemias/ética , Política , Racismo/ética , Betacoronavirus , COVID-19 , Mudança Climática , Infecções por Coronavirus/etnologia , Infecções por Coronavirus/psicologia , Disparidades em Assistência à Saúde , Humanos , Princípios Morais , Pneumonia Viral/etnologia , Pneumonia Viral/psicologia , Racismo/psicologia , SARS-CoV-2 , Determinantes Sociais da Saúde , Marginalização Social , Valores Sociais , Estados Unidos/epidemiologia
9.
Behav Brain Sci ; 42: e196, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31744559

RESUMO

It is emphasized that environmental predictability is another important condition that plays roles in slow strategies that are related to innovation; that economic inequality, except as measured by Gross Domestic Product (GDP) per capita, influences innovation; and that switching global life history from a slow to a fast strategy is a response adopted in response to new challenges during the post-Industrial Revolution period.

10.
Exp Ther Med ; 17(3): 1825-1830, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30783455

RESUMO

The present study aimed to explore the correlation between the dynamic serum levels of phospholipase A2 receptor (PLA2R), aldose reductase (AR) and superoxide dismutase 2(SOD2) antibodies with disease activity and treatment response in patients with idiopathic membranous nephropathy (IMN). The present study included 56 patients with IMN who were diagnosed through a renal biopsy and presenting with nephrotic syndrome. The patients were divided into two treatment groups: One treated with cyclophosphamide (CTX) and one with tacrolimus (FK506). Serum was collected prior to treatment, and at 1, 3, 6, 9 and 12 months after the start of the 12-month-long therapy. Samples were tested by ELISA to measure anti-PLA2R, anti-AR and anti-SOD2 antibody titers. In addition, urinary protein excretion, serum albumin (Alb) and other blood biochemical indexes were measured. Theanti-PLA2R antibody positivity rate was 71.43% in the patients prior to treatment. After 12 months of treatment, proteinuria and PLA2R antibody levels were decreased, whereas serum Alb was increased. There was no significant difference of remission rates between the CTX and FK506 groups. In conclusion, the results of the present study indicate that the anti-PLA2R antibody level is correlated with the severity of IMN, whereas anti-AR and anti-SOD2 antibody levels are not. In addition, there was no significant difference between the CTX and FK506 groups in regards to the remission rates of patients with IMN.

11.
Int J Behav Med ; 25(1): 141-149, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29030808

RESUMO

PURPOSE: Childhood overweight and obesity is on the rise in China and in Chinese cities in particular. The aim of this study is to explore the extent of income differences in childhood overweight in Shanghai, China, and examine demographic, social, and behavioral explanations for these differences. METHODS: Using the 2014 Child Well-Being Study of Shanghai, China-a survey that included extensive contextual information on children and their families in China's most populous city, prevalence rates and adjusted odds ratios of child overweight and obesity at age 7 were calculated by income tercile controlling for a wide variety of sociodemographic variables. RESULTS: District aggregate income increases the odds of child overweight/obesity, but only for boys. In contrast, rural hukou status was associated with lower odds of overweight/obesity for girls. CONCLUSIONS: Boys at age 7 are more likely to be overweight and obese than girls. District income further increases this likelihood for boys, while rural hukou status decreases this likelihood for girls, suggesting that preferences for boys and thinness ideals for girls may play a role in the income patterning of childhood overweight and obesity.


Assuntos
Índice de Massa Corporal , Características da Família , Obesidade Infantil/epidemiologia , Classe Social , Adolescente , Criança , China/epidemiologia , Feminino , Humanos , Masculino , Prevalência , População Rural/estatística & dados numéricos , Distribuição por Sexo , Fatores Sexuais , Magreza/epidemiologia , População Urbana/estatística & dados numéricos
12.
Artigo em Inglês | MEDLINE | ID: mdl-28926964

RESUMO

Using Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K), we investigated the relationship between poverty and academic trajectories for children in immigrant families in the United States. We used family socioeconomic status (SES) which considers parental education, parental occupation, and family income to define poverty in correspondence with the U.S. federal poverty threshold. Three dimensions of poverty were examined including depth (i.e., not-poor, near-poor, poor or extreme poor), stability (i.e., continuously or intermittently), and duration (i.e., for how many times in poverty). Our results indicated that living in poverty, particularly when it was extreme, volatile, and for long spell could compromise children's reading and math achievements during the first nine schooling years. Children of immigrants were doing as well as, if not better than, children of native-borns in certain areas (i.e., math) or in facing of certain pattern of poverty (i.e., long-spell). However, deep poverty and volatile changes in family SES could compromise academic achievements for children of immigrants throughout their first nine years of schooling, a period holds important key to their future success. Implications to practice and policy as well as future directions were discussed.


Assuntos
Sucesso Acadêmico , Escolaridade , Emigrantes e Imigrantes/estatística & dados numéricos , Pobreza , Classe Social , Adolescente , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Estados Unidos
13.
J Med Internet Res ; 19(5): e150, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28473306

RESUMO

BACKGROUND: Hospitalized patients in the United States experience falls at a rate of 2.6 to 17.1 per 1000 patient-days, with the majority occurring when a patient is moving to, from, and around the bed. Each fall with injury costs an average of US $14,000. OBJECTIVE: The aim was to conduct a technology evaluation, including feasibility, usability, and user experience, of a medical sensor-based Intranet of things (IoT) system in facilitating nursing response to bed exits in an acute care hospital. METHODS: Patients 18 years and older with a Morse fall score of 45 or greater were recruited from a 35-bed medical-surgical ward in a 317-bed Massachusetts teaching hospital. Eligible patients were recruited between August 4, 2015 and July 31, 2016. Participants received a sensor pad placed between the top of their mattress and bed sheet. The sensor pad was positioned to monitor movement from patients' shoulders to their thighs. The SensableCare System was evaluated for monitoring patient movement and delivering timely alerts to nursing staff via mobile devices when there appeared to be a bed-exit attempt. Sensor pad data were collected automatically from the system. The primary outcomes included number of falls, time to turn off bed-exit alerts, and the number of attempted bed-exit events. Data on patient falls were collected by clinical research assistants and confirmed with the unit nurse manager. Explanatory variables included room locations (zones 1-3), day of the week, nursing shift, and Morse Fall Scale (ie, positive fall history, positive secondary diagnosis, positive ambulatory aid, weak impaired gait/transfer, positive IV/saline lock, mentally forgets limitations). We also assessed user experience via nurse focus groups. Qualitative data regarding staff interactions with the system were collected during two focus groups with 25 total nurses, each lasting approximately 1.5 hours. RESULTS: A total of 91 patients used the system for 234.0 patient-days and experienced no bed falls during the study period. On average, patients were assisted/returned to bed 46 seconds after the alert system was triggered. Response times were longer during the overnight nursing shift versus day shift (P=.005), but were independent of the patient's location on the unit. Focus groups revealed that nurses found the system integrated well into the clinical nursing workflow and the alerts were helpful in patient monitoring. CONCLUSIONS: A medical IoT system can be integrated into the existing nursing workflow and may reduce patient bed fall risk in acute care hospitals, a high priority but an elusive patient safety challenge. By using an alerting system that sends notifications directly to nurses' mobile devices, nurses can equally respond to unassisted bed-exit attempts wherever patients are located on the ward. Further study, including a fully powered randomized controlled trial, is needed to assess effectiveness across hospital settings.


Assuntos
Acidentes por Quedas/prevenção & controle , Redes de Comunicação de Computadores/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Projetos Piloto , Estados Unidos
14.
Demography ; 54(1): 93-118, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28054253

RESUMO

Despite a large literature documenting the impact of childbearing on women's wages, less understanding exists of the actual employment trajectories that mothers take and the circumstances surrounding different paths. We use sequence analysis to chart the entire employment trajectory for a diverse sample of U.S. women by race/ethnicity and nativity in the first year following childbirth. Using data from the 1996-2008 panels of the Survey of Income and Program Participation and sample selection models, we find that women employed before childbirth show a high degree of labor market continuity. However, a notable share of them (24 %) took less stable paths by dropping out or scaling back work. In addition, mothers' attachment to the labor force is simultaneously supported by personal endowments and family resources yet constrained by economic hardship and job characteristics. Moreover, mothers' employment patterns differ by race/ethnicity and nativity. Nonwhite women (blacks, Hispanics, and Asians) who were employed before childbirth exhibited greater labor market continuation than white women. For immigrant women, those with a shorter length of residence were more likely to curtail employment than native-born women, but those with longer duration of residence show greater labor force attachment. We discuss the implications of these findings for income inequality and public policy.


Assuntos
Emprego/estatística & dados numéricos , Etnicidade/estatística & dados numéricos , Renda/estatística & dados numéricos , Parto , Grupos Raciais/estatística & dados numéricos , Adulto , Características da Família , Feminino , Humanos , Estudos Longitudinais , Fatores Socioeconômicos
15.
Nanoscale ; 8(46): 19359-19367, 2016 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-27845467

RESUMO

MnZn ferrite (MnZnFe2O4, MZF) nanoparticles (NPs) represent an intriguing class of magnetic NPs in terms of composition-tunable magnetic properties, but the ability to control the size and morphology is essential to exploit such properties. This report describes the findings of an investigation of the size and morphology controllability in terms of growth kinetics of the NPs in a thermochemical synthesis process. MZF NPs of different sizes were synthesized at different temperatures. In addition to shape evolution, the overall size of the as-synthesized magnetic NPs is shown to increase with the reaction temperature and reaction time, revealing that the size growth process can be described by an aggregative growth mechanism. While the apparent rate constant decreases with the reaction temperature, the growth factor remains at 1-2, consistent with a low-dimensionality growth mode. Higher temperature and longer reaction time apparently favor the formation of cubic shapes. The dependence of the overall average particle size on the reaction temperature yields a diffusional activation energy in the order of 10-20 kJ mol-1, a value slightly smaller than those reported for aggregative growth of other types of NPs in solutions. The unravelling of the kinetic parameters provides some new insights into the development of strategies for synthesizing MZF NPs with controllable sizes and shapes.

16.
Huan Jing Ke Xue ; 37(5): 1915-22, 2016 May 15.
Artigo em Chinês | MEDLINE | ID: mdl-27506048

RESUMO

Spatial variability of soil organic matter and its distribution pattern are the hot issues of soil scientific research. Selecting Haigouhe watershed as the study area, this paper mainly focused on the spatial variability, distribution pattern and its impact factors of SOM in the surface soil by classical statistics, Geo-statistics and "3S" technology. The results showed that: compared with the other black soil areas, the SOM content in Haigouhe watershed was a little lower, there was a spatial autocorrelation, and a moderate variability. Random factors, such as human activities, cultivation measures and so on, had little impact on the spatial variation, while the structural factors had a dominant function, and there was a remarkable spatial anisotropy of SOM. The SOM content reduced gradually from east to west with the familiar changes of height, so the co-kriging interpolation, selecting elevation as the co-variate, was employed to improve the accuracy. The spatial variability of SOM and its distribution pattern in Haigouhe watershed were greatly affected by topography and land use but weakly influenced by traffic, villages and other social factors. The surrounding environment of the samples would increase the uncertainty of spatial variability and interpolation of SOM and it cannot be ignored in future studies. In summary, it was a significant scientific research to analyze the spatial variability, distribution pattern of SOM and its main impact factors in a mollisol hilly watershed of China.


Assuntos
Monitoramento Ambiental , Solo/química , China , Meio Ambiente , Análise Espacial
17.
Ying Yong Sheng Tai Xue Bao ; 27(11): 3593-3599, 2016 Nov 18.
Artigo em Chinês | MEDLINE | ID: mdl-29696857

RESUMO

In a 3-year field experiment, effects of reducing N fertilizer, straw returning and dicyandiamide (DCD) application on wheat yield and nitrogen budgets under wheat-fallow system were studied in rain-fed region. The experiment was carried out in Yangling of Shaanxi Province, and 4 treatments were installed including no nitrogen (CK), 220 kg N·hm-2 and no straw returning (FP), 150 kg N·hm-2 and straw returning (OPT), 150 kg N·hm-2, 7.5 kg·hm-2 DCD and straw returning (OPT+DCD). The results showed there was no remarkable difference for wheat yield between OPT and FP, but the N use efficiency of the former was 6.1% more than that of the latter, and the apparent N loss ratio was 7.2% less. OPT+DCD increased the average yield of winter wheat by 10.4% and 7.9% respectively compared to OPT and FP, the N use efficiency of winter wheat increased by 20.8% and 28.1%, and the apparent N loss ratio decreased by 8.5% and 15.1%, respectively. NH4+-N content in 0-20 cm of soil increased, accordingly the NO3--N content decreased in 40 to 45 days when DCD was applied.


Assuntos
Agricultura/métodos , Fertilizantes , Guanidinas/química , Nitrogênio/química , Triticum/crescimento & desenvolvimento , China , Chuva , Solo
18.
Arch Gerontol Geriatr ; 60(1): 168-77, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25277446

RESUMO

This study investigates the trajectory of various dimensions of health status among the Chinese elderly in their late years. We used growth-curve analyses on a subsample (n≈2000) of the elderly from the Chinese Longitudinal Health Longevity Survey (CLHLS) who had longitudinal information from 1998 to 2005. Analyses controlled for a large set of individual and family characteristics. Our findings indicate that elderly who had relatively advantaged childhood socioeconomic status (SES) and who regularly engaged in physical and/or leisure activities had significantly healthier well-being than their respective counterparts on all dimensions considered. In addition, regularly participating in physical and/or leisure activities was associated with slow deterioration of health well-being among the Chinese elderly. The results indicate the potential benefits of engaging in physical and/or leisure activities, and consequently, the importance of implementing programs that promote such activities among elders in China.


Assuntos
Povo Asiático/psicologia , Cognição/fisiologia , Nível de Saúde , Saúde Mental , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Inquéritos Epidemiológicos , Humanos , Atividades de Lazer , Longevidade , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Satisfação Pessoal , Qualidade de Vida , Classe Social , Inquéritos e Questionários
19.
Child Dev ; 85(6): 2140-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25156308

RESUMO

This study is the first to test whether receipt of a federal child care subsidy is associated with children of immigrants' school readiness skills. Using nationally representative data (n ≈ 2,900), this study estimates the associations between subsidy receipt at age 4 and kindergarten cognitive and social outcomes, for children of immigrant versus native-born parents. Among children of immigrants, subsidized center-based care (vs. subsidized and unsubsidized home-based care) was positively linked with reading. Among children of native-born parents, those in subsidized center care displayed poorer math skills than those in unsubsidized centers, and more externalizing problems than those in unsubsidized home-based care.


Assuntos
Cuidado da Criança/economia , Desenvolvimento Infantil/fisiologia , Emigrantes e Imigrantes/educação , Financiamento Governamental/economia , Instituições Acadêmicas , Comportamento Infantil/fisiologia , Pré-Escolar , Feminino , Humanos , Estudos Longitudinais , Masculino , Matemática , Leitura , Estados Unidos/etnologia
20.
J Agric Food Chem ; 61(36): 8556-64, 2013 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-23957814

RESUMO

Antrodia cinnamomea is an edible fungus endemic to Taiwan that has been attributed with health promotion benefits. An A. cinnamomea mycelium health food product, which was produced by solid-state culture, was selected as the target for investigation in this study. Fourteen representative metabolites of A. cinnamomea mycelium (EMAC) were selected as index compounds to establish the metabolite profile for evaluation of EMAC product quality. It was also demonstrated that EMAC administration significantly reduced liver inflammation and serum oxidative stress in vivo. 4-Acetylantroquinonol B obtained by a bioactivity-guided fractionation from EMAC was able to not only inhibit LPS-induced nitric oxide formation in macrophages but also protect against ethanol-induced oxidative stress in liver cells. The results suggest this A. cinnamomea product might be a potent antioxidative and anti-inflammatory supplement for chemoprevention.


Assuntos
Anti-Inflamatórios , Anticarcinógenos , Antioxidantes , Antrodia/química , Alimentos Orgânicos , Micélio/química , Animais , Antrodia/metabolismo , Quimioprevenção , Etanol/farmacologia , Promoção da Saúde , Células Hep G2 , Humanos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Metaboloma , Camundongos , Camundongos Endogâmicos ICR , Óxido Nítrico/biossíntese , Estresse Oxidativo/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA