期刊文献+
共找到2,021篇文章
< 1 2 102 >
每页显示 20 50 100
Dynamics of information diffusion and disease transmission in time-varying multiplex networks with asymmetric activity levels
1
作者 谢笑笑 霍良安 +1 位作者 董雅芳 程英英 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期690-699,共10页
While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer ... While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer coupling model to explore the interactions between information and disease.The upper layer describes the diffusion of disease-related information,and the lower layer represents the disease transmission.We then use power-law distributions to examine the influence of asymmetric activity levels on dynamic propagation,revealing a mapping relationship characterizing the interconnected propagation of information and diseases among partial nodes within the network.Subsequently,we derive the disease outbreak threshold by using the microscopic Markov-chain approach(MMCA).Finally,we perform extensive Monte Carlo(MC)numerical simulations to verify the accuracy of our theoretical results.Our findings indicate that the activity levels of individuals in the disease transmission layer have a more significant influence on disease transmission compared with the individual activity levels in the information diffusion layer.Moreover,reducing the damping factor can delay disease outbreaks and suppress disease transmission,while improving individual quarantine measures can contribute positively to disease control.This study provides valuable insights into policymakers for developing outbreak prevention and control strategies. 展开更多
关键词 information diffusion disease transmission asymmetric activity levels quarantine strength
下载PDF
Diagnostic value of plasminogen activity level in acute mesenteric ischemia 被引量:3
2
作者 Yusuf Gunerhan Neset Koksal +2 位作者 Munire Kayahan Yavuz Eryavuz Hilal Sekban 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第16期2540-2543,共4页
AIM: To investigate the changes in plasminogen activity level during mesenteric ischemia. METHODS: We performed laparotomy in 90 female Wistar-Albino rats (average weight 230 g). In sham groups (SL) (GroupsⅠand Ⅱ) t... AIM: To investigate the changes in plasminogen activity level during mesenteric ischemia. METHODS: We performed laparotomy in 90 female Wistar-Albino rats (average weight 230 g). In sham groups (SL) (GroupsⅠand Ⅱ) the superior mesenteric artery (SMA) and vein (SMV) were explored, but not tied. In SMA groups (Groups Ⅲ and Ⅳ) the SMA was ligated, and in SMV groups (Groups Ⅴ and Ⅵ) the SMV was ligated. On re-laparatomy 2 mL of blood was drawn at 1 h in groupsⅠ, Ⅲ and Ⅴ, and at 3 h in groups Ⅱ, Ⅳ and Ⅵ. Plasminogen levels were assessed and comparisons were made between groups and within each group. RESULTS: The mean plasminogen activity in the SL group was significantly higher than SMA (25.1 ± 10.8 vs 11.8 ± 4.6, P < 0.001) or SMV (25.1 ± 10.8 vs 13.7 ± 4.4, P < 0.001) groups both at 1 h and at 3 h (29.8 ± 8.9 vs 15.1 ± 5.7, P < 0.0001; 29.8 ± 8.9 vs 14.2 ± 2.9, P < 0.0001). There were no significant differences between the values of SMA and SMV groups at 1 h (P = 0.28) and at 3 h (P = 0.71). In each group, plasminogen activity levels did not change significantly between the two measurements performed at 1 h and 3 h. CONCLUSION: We conclude that blood plasminogen activities decrease during early phases of both arterial and venous mesenteric ischemia which may be a useful marker for early diagnosis. 展开更多
关键词 Mesenteric ischemia NECROSIS activity level
下载PDF
Measurement invariance and latent mean differences of the Chinese version physical activity self-efficacy scale across gender and education levels 被引量:1
3
作者 Han Chen Jun Dai Yong Gao 《Journal of Sport and Health Science》 SCIE 2019年第1期46-54,共9页
Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has... Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has rarely been conducted in China. The current study aims to examine(1) the unidimensionality of a shortened Chinese version of PA self-efficacy scale(S-PASESC);(2) the measurement invariance of S-PASESC across gender and levels of education;(3) the latent factor mean difference between gender and levels of education;(4) the direct effects of self-efficacy on PA by different gender and education levels; and(5) the comparisons of the direct effects of self-efficacy on PA across gender and education levels.Methods: The participants were 5 th through 11 th grade public school students recruited from 7 cities located in different geographic regions of China. The final data include a total of 3003 participants(49.7% boys) who have completed the scales.Results: Confirmatory factor analysis(CFA) test supported the unidimensionality of S-PASESC. The S-PASESC is invariant across gender and 3 levels of education at both configural, full metric, and full scalar levels. Findings from latent mean comparisons showed that boys reported higher PA self-efficacy than girls. Students' perceived PA self-efficacy tend to decrease from elementary to high school. Finally, self-efficacy positively related to PA by groups of different gender and education levels and the relationship between self-efficacy and PA is stronger among middle school boys than girls.Conclusion: Findings suggest S-PASESC is a valid scale for measuring Chinese students' PA self-efficacy. 展开更多
关键词 Chinese adolescents Education levels Factor analysis GENDER LATENT mean comparison MEASUREMENT INVARIANCE Physical activity SELF-EFFICACY scale
下载PDF
A study of the relationship between expression level of TRF1 protein and telomerase activity in human acute leukemia 被引量:4
4
作者 施继敏 黄河 +1 位作者 陈巧芳 林茂芳 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第2期154-158,共5页
Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase, Methods: A quantitativ... Objective: To study the expression level of TRF1 (telomeric repeat binding factor 1) protein in human acute leukemia and relationship between expression level of TRF1 protein and telomerase, Methods: A quantitative Western±Blot technique was developed using anti±TRF1^33±277 monoclonal antibody and GST±TRFI purity protein as a standard to further determine the expression level of TRF1 protein in total proteins extracted from clinical specimens. Results: Bone marrow tissues of 20 acute leukemia patients were studied, 11 healthy donors' bone marrows were taken as a control. The expression level of TRF1 protein was significantly higher (P〈0.01) in normal bone marrow ((2.2174±0.462) μg/μl) than that of acute leukemia patients ((0.7544±0.343) μg/μl), But there was no remarkable difference between ALL and ANLL patients ((0.6184±0.285) μg/μl vs (0.8454±0.359) μg/μl, P〉0.05). After chemotherapy, TRFI expression level of patients with complete remission elevated ((0.7724±0.307)/μg/μl vs (1.6834±0,344)μg/μl, P〈0.01 ), but lower than that of normal ((2.2174±0.462)/μg/μl, P〈0.01). There was no significantly difference after chemotherapy ((0.7264±0.411) μg/μl vs (0.895±0.339) μg/μl,p〉0.05). TRF1 expression level of patients with complete remission is higher than that of patients without complete remission ((1,683±0.344)μg/μl vs (0.895±0.339)μg/μl P〈0.01). All samples were determined for telomerase activity. It was confirmed that the activity of telomerase in normal bone marrow was lower than that of acute leukemia patients ((0.125±0.078) μg/μl vs (0.765±0.284)μg/μl, P〈0.01). There was no significant difference of expression level ofTRF I protein between ALL and ANLL patients ((0.897±0.290) μg/μl vs (0.677±0.268) μg/μl, P〉0.05). After chemotherapy, telomerase activity of patients with complete remission decreased ((0.393±0.125) μg/μl), but was still higher than that of normal ((0.125±0.078) μg/μl, P〈0.01). Conclusion: The expression level of TRF1 protein has correlativity to the activity of telomerase (P〈0.001). 展开更多
关键词 Acute leukemia (AL) Human telomeric repeat binding factor protein 1 (TRFI) Monoclonal antibody Expression level of TRF1 protein Telomerase activity
下载PDF
Evolution of the Level of Sunspot Activity in Solar Cycles I. Evolution in the Descending Phase 被引量:2
5
作者 Jia-Long Wang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2006年第3期354-362,共9页
Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the e... Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the evolution of the level is statistically studied for the period from the month which is just 48 months before the minimum to the minimum in the descending phase, using the observed data of Solar Cycles 10 to 22. Our results show (1) for 46 months (94%) of the studied 49 months it is found that for a given month, the distribution of the 13 pairs which come from the 13 solar cycles on a log Ri - Di plane may be fitted by a straight line with a correlation coefficient larger than the critical one at confidence level a = 5%, and for 36 months (73%) the fitting is even better, for a = 1%; (2) time variations of these two parameters and their correlations in the studied period can be described respectively by functions of time, whose main trends may be expressed by a linear or simple curvilinear function; (3) the evolutionary path of the level of sunspot activity may be represented by a logarithmic function as log/~ = 0.704 lnDi - 0.291. 展开更多
关键词 Sun - sunspots - active level evolution
下载PDF
ENSO Index Variations and Links with Solar and Volcanic Activity
6
作者 Valentina V. Zharkova Irina Vasilieva 《Natural Science》 2024年第4期25-44,共20页
In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SP... In this paper, we investigated the Oceanic Niño Index (ONI), for simplicity called in this paper an El Nino Southern Oscillation (ENSO) index in 1950-2023 by applying the wavelet spectral transform and the IBM SPSS correlations analysis. ONI follows the three months’ current measurements of the average temperature of the sea surface in the East-Central tropical part of the Pacific Ocean nearby the international line of the date change over the average sea surface temperature over the past 30 years. The ENSO index is found to have a strong (>87%) correlation with the Global Land-Ocean Temperature (GLOT). The scatter plots of the ENSO-GLOT correlation with the linear and cubic fits have shown that the ENSO index is better fit by the cubic polynomial increasing proportionally to a cubic power of the GLOT variations. The wavelet analysis allowed us to detect the two key periods in the ENSO (ONI) index: 4 - 5 years and 12 years. The smaller period of 4.5 years can be linked to the motion of tectonic plates while the larger period of 12 years is shown to have a noticeable correlation of 25% with frequencies of the underwater (submarine) volcanic eruptions in the areas with ENSO occurrences. Not withholding any local terrestrial factors considered to contribute to the ENSO occurrences, we investigated the possibility of the volcanic eruptions causing ENSO to be also induced by the tidal forces of Jupiter and Sun showing the correlation of the underwater volcanic eruption frequency with the Jupiter-Earth distances to be 12% and with the Sun-Earth distances, induced by the solar inertial motion, in January, when the Earth is turned to the Sun with the southern hemisphere where the ENSO occurs, to become 15%. Hence, the underwater volcanic eruptions induced by tidal forces of Jupiter and Sun can be the essential additional factors imposing this 12 year period of the ENSO (ONI) index variations. 展开更多
关键词 Sun: Magnetic Field Sun: Solar activity Sun: Inertial Motion Earth: Temperature Earth: Sea level Earth: Ice Area
下载PDF
Antiepileptic activity of lobeline isolated from the leaf of Lobelia nicotianaefolia and its effect on brain GABA level in mice
7
作者 Abrar M Tamboli Rukhsana A Rub +1 位作者 Pinaki Ghosh SL Bodhankar 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第7期537-542,共6页
Objective:To investigate the anticonvulsant activity of the lobeline isolated from the Lobelia nicotianaefolia in chemoconvulsant-induced seizures and its biochemical mechanism by investigating relationship between se... Objective:To investigate the anticonvulsant activity of the lobeline isolated from the Lobelia nicotianaefolia in chemoconvulsant-induced seizures and its biochemical mechanism by investigating relationship between seizure activities and altered gamma amino butyric acid(GABA)in brain of mice in Pentylenetetrazol(PTZ) seizure models.Methods:The anticonvulsant activity of the isolated lobelinc(5,10,20 and 30 mg/kg.i.p.) was investigated in PTZ and strychnine induced seizures in mice and the effect of isolated lolieline on brain GABA level in seizures induced by PTZ.Diazepam was used as reference anticonvulsant drugs for comparison.Results:Isolated lobeliue(10,20 and 30 nig/kg.up.) significautly delayed and antagonized(P < 0.050-0.001)the onset of PTZ-induced seizures.It also antagonized strychnine induced seizures.The mortality was also prevented in the test group of animals.In biochemical evaluation,isolated lolieline(5,10and 20 mg/kg,i.p.) significantly increased the brain GABA level.And at dose of 30 mg/kg GABA level showed slight decrease in PTZ model.Conclusions:In our findings,isolated lolieline(20mg/kg) exhibited potent anticonvulsant activity against PTZ induced seizures.Also a biochemical evaluation suggested significant increase in harain GABA level at 20 nig/kg up.of isolated lolieline.Hence,we may propose that lolieline reduces epileptic seizures by enhancing the GABA release supporting the GABAergic mechanism. 展开更多
关键词 LOBELIA nicotianaefolia Lobeline BRAIN GABA level ANTIEPILEPTIC activity Pentylenetetrazol(PTZ) STRYCHNINE
下载PDF
Body Composition, Dietary Intake and Physical Activity Level of Sedentary Adult Indian Women
8
作者 Gurpreet Kaur Kiran Bains Harpreet Kaur 《Food and Nutrition Sciences》 2012年第11期1577-1585,共9页
Age related changes in body composition are associated with long term dietary intake profiles. Age related increase in body fat is primarily attributed to decline in physical activity and basal metabolic rate as well ... Age related changes in body composition are associated with long term dietary intake profiles. Age related increase in body fat is primarily attributed to decline in physical activity and basal metabolic rate as well as dietary intake. The study was designed to assess the body composition, dietary intake and physical activity level of sedentary adult women of different age groups. A cross-sectional study was conducted on 152 sedentary adult women comprised of students and faculty from Punjab Agricultural University, Ludhiana. The relationship of body composition with dietary factors and physical activity level of women in four age groups i.e. 21 - 30, 31 - 40, 41 - 50 and 51 - 60 years was determined. A gradual increase (p ≤ 0.05) in anthropometric and body composition parameters such as weight, waist circumference, hip circumference, body mass index, fat mass and visceral fat rating was observed with the advancement of age. The lean body mass was decreased significantly (p ≤ 0.05) as the age progressed, the values for four age groups being 74.9, 68.9, 62.8 and 60.9%, respectively. Contrary to this fat mass increased with age, the corresponding values for four age groups being 15.7, 21.4, 26.6 and 29.2 kg, respectively. The percent adequacy of protein by four age groups was 69.6, 78.2, 80.0 and 66.3, respectively when compared to RDA while fat intake was much higher i.e. 245.5, 271.8, 288.4 and 250.8%, respectively. The energy intake was inadequate among all age groups, however, a significant (p ≤ 0.05) differ- ence was observed in daily energy consumption between the age groups. The mean physical activity level (PAL) of the subjects ranged between 1.49 - 1.60. The physical activity level values showed that majority of the subjects (87% - 94%) were having sedentary life style. Age is a crucial factor associated with body composition. A high fat mass and low lean body mass of the subjects was observed. Their diets were low in protein but high in fat. Majority of the subjects from different age groups had sedentary life style. A diet with higher protein and lesser fat combined with exercise can help in sustaining optimum body composition. 展开更多
关键词 LEAN Body MASS FAT MASS DIETARY Factors Physical activity level
下载PDF
Effects of Physical Activity Levels on Fatigue Perception in Patients with Parkinson’s Disease and Neurologically Healthy Individuals
9
作者 Paulo Cezar Rocha dos Santos Fabio Augusto Barbieri +2 位作者 Diego Orcioli-Silva Lucas Simieli Lilian Teresa Bucken Gobbi 《Health》 2014年第21期2927-2933,共7页
Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical a... Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical activity practice, there are only few studies that verified the influence of the levels of physical activity on fatigue in patients with PD. Objective: The aim of this study was to compare perception of fatigue between individuals with PD and neurologically healthy individuals (control group), considering the physical activity levels;and to verify the relation between physical activity levels and fatigue dimensions for individuals with PD and control group. Methods: Eighty individuals (40 patients with PD and 40 control individuals) participated in this study. Physical activity levels were evaluated through Modified Baecke Questionnaire for Older Adults. Multidimensional Fatigue Inventory (MFI) was used in order to evaluate fatigue dimensions (general, physical and mental fatigue, reduced motivation and activity). MANOVA two-way and Pearson linear correlation test were performed to analyze the data. Results: Patients with PD presented higher levels of fatigue, in all dimensions evaluated by MFI, comparing to control individuals. There was no association between physical activity levels and perception of fatigue for patients with PD and control individuals. Conclusion: Patients with PD showed increased perception of fatigue when compared to control individuals, due to PD characteristics. In addition, the perception of fatigue’s symptom was not influenced and had no relation by the level of physical activity. 展开更多
关键词 Parkinson’s Disease SYMPTOM of FATIGUE Physical activity levels NON-MOTOR SYMPTOM
下载PDF
Physical Activity Level and Adult Saudi Health Related Quality of Life
10
作者 Salwa B. El-Sobkey 《Open Journal of Therapy and Rehabilitation》 2014年第3期106-133,共28页
Purpose: Physical inactivity in Saudi Arabia is a growing challenge to public health. This study aimed to define the relationship between the physical activity level (PAL) and adult Saudi health-related quality of lif... Purpose: Physical inactivity in Saudi Arabia is a growing challenge to public health. This study aimed to define the relationship between the physical activity level (PAL) and adult Saudi health-related quality of life (HRQoL). Methods: Participants of this study were 100 Saudi adult aged from 18 - 70 years. The 36-Item Short-Form Health Status Survey (SF-36) was used to measure the participant’s HRQoL. The SF-36 is comprised of 8 domains. The electronic version of the General Practice Physical Activity Questionnaire was used to categorize participants in terms of physical activity level into;inactive, moderately inactive, moderately active, and active. Descriptive and inferential statistical tests were used to treat the collected data. Results: Results showed that only 17% of the Saudi adults had active PAL. The PAL had significantly positive relationship with 4 domains of HRQoL including: physical functioning (P = 0.004), role limitations caused by physical health problems (P = 0.048), vitality (P = 0.009), and general health (P = 0.044). Results also confirmed that the younger the subject, the higher the PAL (P = 0.0001) and the better the HRQoL. This is true for all domains except the role limitations caused by emotional problems and emotional wellbeing. Conclusion: The poor physical activity level of adult Saudi negatively impacts their HRQoL. 展开更多
关键词 SAUDI PHYSICAL activity level SAUDI Health Related Quality of Life SF-36 Survey General Practice PHYSICAL activity QUESTIONNAIRE
下载PDF
What Is the Relation between Aerobic Capacity and Physical Activity Level in Adults with Congenital Heart Disease?
11
作者 Kelly Ferri Maite Doñate +5 位作者 Mireia Parra Guillermo ROviedo Myriam Guerra-Balic Laia Rojano-Doñate Nicole Blackburn Ricard Serra-Grima 《Congenital Heart Disease》 SCIE 2021年第6期585-595,共11页
Background:Aerobic capacity(AC)in adults with congenital heart disease(CHD)is often reduced,mainly due to low confidence levels towards physical activity(PA).The main objective of this study was to estimate the associ... Background:Aerobic capacity(AC)in adults with congenital heart disease(CHD)is often reduced,mainly due to low confidence levels towards physical activity(PA).The main objective of this study was to estimate the association between PA level and AC(measured as peak of oxygen consumption,VO_(2peak))in adults with CHD.Methods:A total of 183 individuals(83 women and 100 men;mean(SD)age 36.9(11.0)years old)from Vall d’Hebron Hospital,Barcelona-Spain in 2019,participated in this cross-sectional study.The AC was assessed by cardiopulmonary exercise testing(CPET)using a treadmill ramp protocol.Considering values of metabolic equivalent of task(MET,MET-min·week-1)obtained by the short International Physical Activity Questionnaire(IPAQ),participants were divided into three categories of PA:health-enhancing PA(HEPA),minimally active,and inactive.Results:Median(SD)PA was 2737.2(2835.7)MET-min·week-1,with 60 participants(32.8%)reporting HEPA,91(49.7%)minimally active,and 32(17.5%)inactivity.Participants demonstrated a mean VO_(2peak) of 28.9(8.8)mL·Kg^(-1)·min^(-1),showing AC values on average 13%lower than expected in a healthy population.Overall,PA and AC were positively associated.Adjusting for sex and age,an increase of 1000 MET-min·week^(-1) was associated with an increase in VO_(2peak) of 0.8 units(95%CI 0.4–1.2;p<0.001).There were no differences in the degree of increase between sexes(p=0.427).Conclusion:These findings suggest that an increase in PA in patients with CHD significantly improves their AC,and hence,could be recommended when the goal is to improve their physical condition. 展开更多
关键词 Physical activity level aerobic capacity congenital heart disease
下载PDF
Is HOMO Energy Level a Good Parameter to Characterize Antioxidant Activity 被引量:1
12
作者 Hong Yu ZHANG De Zhan CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第8期727-730,共4页
Semiempirical quantum chemical method AM1 was employed to calculate the highest occupied molecular orbital (HOMO) energy levels (E-HOMO) for various types of antioxidants. It was verified that the correlation between ... Semiempirical quantum chemical method AM1 was employed to calculate the highest occupied molecular orbital (HOMO) energy levels (E-HOMO) for various types of antioxidants. It was verified that the correlation between logarithm of free radical scavenging rate constants (1gks) and E-HOMO substantially arises from the correlation between E-HOMO and O-H bond dissociation energies (BDE) of antioxidants. Furthermore, E-HOMO were poorly correlated with the logarithm of relative free radical scavenging rate constants (1gk(3)/k(1)) for various types of antioxidants that possess complex structures (r = 0.5602). So in a broad sense, E-HOMO was not an appropriate parameter to characterize the free radical scavenging activity of antioxidants. 展开更多
关键词 AM1 ANTIOXIDANT free radical HOMO energy level O-H bond dissociation energy structure-activity relationship
下载PDF
EFFECT OF MILD HYPOTHERMIA ON ACTIVITY NITRIC OXIDE SYNTHASE IN CORTICAL NEURONS AND GLYCEMIA LEVELS OF NEONATAL RATS WITH HYPOXIC ISCHEMIC BRAIN DAMAGE
13
作者 Li Zhankui, Li Ruilin, Gou Yale et al (Department of Pediatrics, Second Affiliated Hospital, Xi′an Medical University) 《Journal of Pharmaceutical Analysis》 CAS 1999年第2期128-128,共1页
Through investigating the effect of mild hypothermia on activity of nitric oxide snythase (NOS) in cortical neurons and glycemia levels of neonatal rats with hypoxic ischemic brain damage (HIBD). We studied the mecha... Through investigating the effect of mild hypothermia on activity of nitric oxide snythase (NOS) in cortical neurons and glycemia levels of neonatal rats with hypoxic ischemic brain damage (HIBD). We studied the mechanism of protecting hypoxic ischemic neurons of mild hypothermia. We established neonatal rat HIBD models, used NOS immunohistochemistry and glycemia determination by micromethod. The number of cortical NOS positive neurons after hypoxic ischemia was significantly decreased as compared with controls. The glycemia levels was significantly increased than that controls. No significant difference was found in number of cortical NOS positive neurons and glycemia levels between 31℃ and 34℃ mild hypothemia. The results imply that hypothermia can decrease overproduction of NO through inhibiting the increase of the activity of NOS, and increase the glycemia levels, thus protect the hypoxic ischemic neurons. 展开更多
关键词 MILD RATS EFFECT OF MILD HYPOTHERMIA ON activity NITRIC GLYCEMIA levelS OF NEONATAL RATS WITH HYPOXIC ISCHEMIC BRAIN DAMAGE
下载PDF
Terrestrial Temperature, Sea Levels and Ice Area Links with Solar Activity and Solar Orbital Motion
14
作者 Valentina V. Zharkova Irina Vasilieva 《Natural Science》 2023年第9期233-255,共23页
This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eig... This paper explores the links between terrestrial temperature, sea levels and ice areas in both hemispheres with solar activity indices expressed through averaged sunspot numbers together with the summary curve of eigenvectors of the solar background magnetic field (SBMF) and with changes of Sun-Earth distances caused by solar inertial motion resulting from the gravitation of large planets in the solar system. Using the wavelet analysis of the GLB and HadCRUTS datasets two periods: 21.4 and 36 years in GLB, set and the period of about 19.6 years in the HadCRUTS are discovered. The 21.4-year period is associated with variations in solar activity defined by the summary curve of the largest eigenvectors of the SBMF. A dominant 21.4-year period is also reported in the variations of the sea level, which is linked with the period of 21.4 years detected in the GLB temperature and the summary curve of the SBMF variations. The wavelet analysis of ice and snow areas shows that in the Southern hemisphere, it does not show any links to solar activity periods while in the Northern hemisphere, the ice area reveals a period of 10.7 years equal to a usual solar activity cycle. The TSI in March-August of every year is found to grow with every year following closely the temperature curve, because the Sun moves closer to the Earth orbit owing to gravitation of large planets (solar inertial motion, SIM), while the variations of solar radiation during a whole year have more steady distribution without a sharp TSI increase during the last two centuries. The additional TSI contribution caused by SIM is likely to secure the additional energy input and exchange between the ocean and atmosphere. 展开更多
关键词 Sun: Magnetic Field Sun: Solar activity Sun: Inertial Motion Earth: Temperature Earth: Sea level Earth: Ice Area
下载PDF
Impact assessment of climate change and human activities on annual highest water level of Taihu Lake 被引量:9
15
作者 Qing-fang HU Yin-tang WANG 《Water Science and Engineering》 EI CAS 2009年第1期1-15,共15页
The annual highest water level of Taihu Lake (Zm) is very significant for flood management in the Taihu Basin. This paper first describes the inter-annual and intra-annual traits of Zm from 1956 to 2000. Then, using... The annual highest water level of Taihu Lake (Zm) is very significant for flood management in the Taihu Basin. This paper first describes the inter-annual and intra-annual traits of Zm from 1956 to 2000. Then, using the Mann-Kenall (MK) and Spearman (SP) nonparametric tests, the long-term change trends of area precipitation and pan evaporation in the Taihu Basin are determined. Meanwhile, using the Morlet wavelet transformation, the fluctuation patterns and change points of precipitation and pan evaporation are analyzed. Also, human activities in the Taihu Basin are described, including land use change and hydraulic project construction. Finally, the relationship between Zm, the water level of Taihu Lake 30 days prior to the day of Zm (Z0), and the 30-day total precipitation and pan evaporation prior to the day of Zm (P and E0, respectively) is described based on multi-linear regression equations. The relative influence of climate change and human activities on the change of Zm is quantitatively ascertained. The results demonstrate that: (1) Zm was distinctly higher during the 1980-2000 period than during the 1956-1979 period, and the 30 days prior to the day of Zm are the key phase influencing Zm every year; (2) P increased significantly at a confidence level of 95% during the 1956-2000 period, while the reverse was true for E0; (3) The relationship between Zm, P and E0 distinctly changed after 1980; (4) Climate change and human activities together caused frequent occurrences of high Zm after 1980; (5) Climate change caused a substantially greater Zm difference between the 1956-1979 and 1980-2000 periods than human activities. Climate change, as represented by P and E0, was the dominant factor raising Zm, with a relative influence ratio of 83.6%, while human activities had a smaller influence ratio of 16.4%. 展开更多
关键词 climate change human activities annual highest water level Taihu Lake
下载PDF
Effect of water level fluctuations on temporal-spatial patterns of foraging activities by the wintering Hooded Crane(Grus monacha) 被引量:7
16
作者 Dongmei Zhang Lizhi Zhou Yunwei Song 《Chinese Birds》 CSCD 2015年第3期169-177,共9页
Background:The Yangtze River floodplain provides important wintering habitats for Hooded Cranes(Grus monacha) in China.Fluctuations in the water level change foraging habitat and food availability,affecting their temp... Background:The Yangtze River floodplain provides important wintering habitats for Hooded Cranes(Grus monacha) in China.Fluctuations in the water level change foraging habitat and food availability,affecting their temporal-spatial patterns of foraging activities.It is of considerable importance to investigate the effect of these fluctuations on food availability for wintering Hooded Cranes and their foraging response to these changes.Understanding their behavior patterns is beneficial in protecting the wintering crane population and restoring their wintering habitats.Methods:A field survey of the winter behavior of cranes was carried out at Shengjin Lake from November in 2013 to April in 2014.Habitat variables,as well as the spatial distribution and behavior patterns of wintering cranes at their foraging sites during five stages of water level fluctuation were collected.Based on this data we analyzed the relationship of foraging behavior relative to water level fluctuations and habitat types.Results:The foraging habitats used by Hooded Cranes varied at the different water level stages.As the water level decreased,the use of meadows and mudflats increased.When the water dropped to its lowest level,the use by the Hooded Crane in the mudflats reached a peak.There were statistically significant differences in time budget in the three types of habitats over the five stages of the water level.In the mudflats,the foraging behavior and maintenance behavior varied significantly with the water level,while the alert behavior showed little variation.Analysis of a generalized linear model showed that the five water level stages and three habitat types had a significant effect on foraging behavior,while the combined effect of these two variables was significant on the foraging time budget and the length of foraging activity of the Hooded Crane.Conclusions:With the decrease in the water level,the use of mudflats by Hooded Cranes increased correspondingly.Food availability in different habitats was affected by changes in the water level.The Hooded Crane adjusted its foraging patterns and made full use of the three available types of habitat in order to acquire enough food in response to fluctuations in the water level. 展开更多
关键词 Water level FLUCTUATIONS FORAGING activity Temporal-spatial pattern Hooded CRANE GRUS monacha
下载PDF
Does knowledge of physical activity recommendations increase physical activity among Chinese college students? Empirical investigations based on the transtheoretical model 被引量:3
17
作者 Kahar Abula Peter Gropel +1 位作者 Kai Chen Jürgen Beckmann 《Journal of Sport and Health Science》 SCIE 2018年第1期77-82,共6页
Background: Based on the transtheoretical model, the current study investigated whether awareness of physical activity(PA) recommendations had an impact on the stages of PA behavior change and levels of PA among Chine... Background: Based on the transtheoretical model, the current study investigated whether awareness of physical activity(PA) recommendations had an impact on the stages of PA behavior change and levels of PA among Chinese college students.Methods: In Study 1, with a cross-sectional study design, 9826 students were recruited, and their knowledge of international PA recommendations,PA stage distribution, and self-reported PA level were surveyed. Pearson's χ2 test was used to test whether those participants who were aware and not aware of PA guidelines were equally distributed across the stages of PA behavior, and independent t test was conducted to test the group difference in the actual levels of PA. In Study 2, 279 students who were not aware of the PA recommendations were randomly allocated to either an intervention group or a control group, and only those in the intervention group were presented with international PA guidelines. In both groups,students' PA stages and PA level were examined before the test and then 4 months post-test. Mc Nemar's test for correlated proportions and repeated-measures analysis of variance were conducted to examine the changes in PA stage membership and PA level after the intervention.Results: Study 1 results revealed that only 4.4% of the surveyed students had correct knowledge of PA recommendations. Those who were aware of the recommendations were in later stages of PA behavior(χ~2(4) = 167.19, p < 0.001). They were also significantly more physically active than those who were not aware of the recommendations(t(443.71) = 9.00, p < 0.001, Cohen's d = 0.53). Study 2 results demonstrated that the intervention group participants who were at the precontemplation and contemplation stages at the pre-test each progressed further in the PA stages in the post-test(χ~2(1) = 112.06, p < 0.001; χ~2(1) = 118.76, p = 0.03, respectively), although no significant change in PA level was observed(t(139) < 1, p = 0.89).Conclusion: The results showed that awareness of the PA recommendations was associated with higher stages and levels of PA behavior, and a brief educational exposure to PA recommendations led to improved stages of PA behavior but no change in the levels of PA among Chinese college students. More effective public health campaign strategies are needed to promote the dissemination of the PA recommendations and to raise the awareness of the Chinese student population. 展开更多
关键词 Behavior change Physical activity level Physical activity recommendations Public health policy Stages of change Transtheoretical model
下载PDF
Mediating role of physical activity in the relationship between psychological distress and intimate relationships among stroke patients 被引量:1
18
作者 Chang-Yue Luo Peng Jiao +2 位作者 Shu-Min Tu Lin Shen Yong-Mei Sun 《World Journal of Psychiatry》 SCIE 2023年第12期1096-1105,共10页
BACKGROUND Stroke patients often experience psychological distress,which can impact their intimate relationships with spouses,subsequently influencing their treatment and recovery.Physical activity is considered a key... BACKGROUND Stroke patients often experience psychological distress,which can impact their intimate relationships with spouses,subsequently influencing their treatment and recovery.Physical activity is considered a key rehabilitation method for stroke patients.This paper aims to analyze whether psychological distress affects intimate relationship between spouses through physical activity.AIM To explore the mediating effect of physical activity between psychological distress and intimate relationship in stroke patients.METHODS A total of 256 stroke patients who underwent treatment at the First People’s Hospital of Shangqiu between July 2021 and July 2022 were enrolled in this study.The participants completed questionnaires,including the Kessler Psychological Distress Scale(K10),the Quality of Relationship Index(QRI),International Physical Activity Questionnaire,and a general information questionnaire.Data analysis were performed using SPSS 23.0.The Harman test was employed to detect common method deviations,and Spearman correlation was used for correlation analysis.The mediating effect was assessed using Process 3.4.1,with significance testing of the regression coefficients conducted using the bias-corrected percentile Bootstrap method(5000 iterations,95%confidence interval).Statistical significance was set at P<0.05.RESULTS The results showed that patients scored an average of 21.61±6.44 points on the K10,32.40±6.19 points on the QRI;the median physical activity level according to the International Physical Activity Questionnaire was 1861(566,2846)MET·min/w.The level of physical activity(the physical activity intensity of the patients reflected by the Interna-tional Physical Activity Questionnaire-Long Form scale)negatively correlated with psychological distress and intimacy(P<0.05),and positively correlated with each other(P<0.05),with the correlation stronger at lower physical activity levels compared to higher ones.The mediating effect of physical activity between psychological distress and intimate relationship was calculated to be 40.23%.Bootstrap analysis further validated the results.The mediating effect of psychological distress on intimate relationships through physical activity level was-0.284,with a confidence interval of-0.409 to-0.163,excluding 0,confirming a significant mediating effect of psychological distress on intimate relationships.CONCLUSION Physical activity significantly affects relationship between psychological distress and intimate relationships among stroke patients.Addressing the role of physical activity may have implications for improving patient outcomes and rehabilitation strategies. 展开更多
关键词 STROKE Cross-sectional study Psychological distress Intimate relationship Mediating effect Physical activity level
下载PDF
Comparison of daily physical activity parameters using objective methods between overweight and normal-weight children
19
作者 Jonghoon Park Kazuko Ishikawa-Takata +5 位作者 Sangjik Lee Eunkyung Kim Kiwon Lim Hyungryul Kim In-Sook Lee Shigeho Tanaka 《Journal of Sport and Health Science》 SCIE 2018年第2期210-217,共8页
Purpose: The purpose of the present study was to determine if there were any differences in various aspects of physical activity such as energy expenditure, intensity, and type of activity between normal-weight and ov... Purpose: The purpose of the present study was to determine if there were any differences in various aspects of physical activity such as energy expenditure, intensity, and type of activity between normal-weight and overweight boys.Methods: Children aged 9—12 years were recruited from 2 elementary schools located in different urban districts in Republic of Korea. The present study included 45 Korean boys, of which 19 were normal-weight and 26 were overweight. Daily physical activity was estimated over the same 1-week study period under free-living conditions using the doubly labeled water(DLW) method and a tri-axial accelerometer. Resting metabolic rate(RMR) was measured using the Douglas bag method and open-circuit indirect calorimetry. We calculated the physical activity level(PAL) as the total energy expenditure(TEE)/RMR.Results: PAL was not significantly different between the groups. In the accelerometer data, time spent in locomotive moderate-to-vigorous physical activity(MVPA) was significantly lower in overweight boys than in normal-weight subjects, whereas other variables including non-locomotive activity did not differ between groups. In addition, among all participants, time spent in total locomotive activity was significantly associated with PAL. Time spent in locomotive MVPA was significantly associated with PAL.Conclusion: Overweight boys may be less physically active based on locomotive MVPA, which was positively related with PAL. Our findings suggest that the contribution of locomotive MVPA to the increase in PAL was relatively significant. 展开更多
关键词 Accelerometer Doubly labeled water Korean elementary boys Locomotive moderate-to-vigorous physical activity Obesity Physical activity level
下载PDF
Active Contours and Mumford-Shah Segmentation Based on Level Sets
20
作者 NASSIR H.SALMAN 刘重庆 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第1期48-53,共6页
This paper is to detect regions (objects) boundaries, also to isolate and extract individual components from a medical image. This can be done using an active contours to detect regions in a given image, based on tech... This paper is to detect regions (objects) boundaries, also to isolate and extract individual components from a medical image. This can be done using an active contours to detect regions in a given image, based on techniques of curve evolution, Mumford Shah functional for segmentation and level sets. The paper classified the images into different intensity regions based on Markov random field, then detected regions whose boundaries are not necessarily defined by gradient by minimizing an energy of Mumford Shah functional for segmentation which can be seen as a particular case of the minimal partition problem. In the level set formulation, the problem becomes a mean curvature flow like evolving the active contour, which will stop on the desired boundary. The stopping term does not depend on the gradient of the image, as in the classical active contour and the initial curve of level set can be anywhere in the image, and interior contours are automatically detected. The final image segmentation is one closed boundary per actual region in the image. 展开更多
关键词 active counters level set methods SEGMENTATION energy minimization shape recovery Markov random field
下载PDF
上一页 1 2 102 下一页 到第
使用帮助 返回顶部