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1.
Journal of Physiology and Biochemistry - The browning of white adipose tissue (WAT) has attracted considerable attention in the scientific community as a popular strategy for enhancing energy...  相似文献   
2.
The objective of this study was to assess the species composition, abundance and habitat association of non-volant small mammals from grassland, Acacia woodland, farmland, riverine forest, bushland and wooded grassland habitats in Gibe Sheleko National Park, southwestern Ethiopia. Data were collected using 49 Sherman live traps in 70 × 70 m sized girds and visual observations from December 2018 to August 2020. A total of 937 small mammals belonging to 10 species were captured and directly identified. The identified small mammal species and their relative abundance include Arvicanthis niloticus (7.04%), Crocidura olivieri (1.92%), Grammomys dolichurus (3.84%), Lemniscomys striatus (10.25%), Mastomys awashensis (24.55%), Mastomys natalensis (33.83%), Mus tenellus (0.85%), Myomys fumatus (6.30%), Rattus rattus (4.70%) and Stenocephalemys albipes (6.72%). Hystrix cristata, Xerus rutilus and Tachyoryctes splendens were documented through observation. The highest number of species (6) was registered at farmland and wooded grassland followed by bushland and riverine forest (5) and Acacia woodland and grassland (4). Lemniscomys striatus, M. awashensis and M. natalensis were common in all habitats. More, 216 (23.05%) individuals were recorded in farmland, while the least, 111 (11.85%) were recorded in Acacia woodland. The study area has various topographical land settings additional study is needed using different traps.  相似文献   
3.
We propose a two-stage model for time series data of counts from multiple locations. This method fits first-stage model(s) using the technique of iteratively weighted filtered least squares (IWFLS) to obtain location-specific intercepts and slopes, with possible lagged effects via polynomial distributed lag modeling. These slopes and/or intercepts are then taken to a second-stage mixed-effects meta-regression model in order to stabilize results from various locations. The representation of the models from the stages into a combined mixed-effects model, issues of inference and choices of the parameters in modeling the lag structure are discussed. We illustrate this proposed model via detailed analysis on the effect of air pollution on school absenteeism based on data from the Southern California Children's Health Study.  相似文献   
4.
This study examines the association between a household's degree of vulnerability to food crisis and the incidence of deaths using primary survey data carried out to look at the demographic consequences of drought and famine in the drought-prone areas of northern Ethiopia. Retrospective data on the occurrences of deaths within a household were collected for the period 1984 to 1994. Consistent with previous studies, the findings confirm that mortality was clustered among the age groups 1-4 and 5-9 and varied considerably by famine and non-famine years. Enormous variation in incidence of deaths was also observed by region, ethnicity and religion. Most importantly, the analysis provides substantial evidence that the level of household vulnerability to food crisis is strongly related to the number of hunger-related deaths reported in a household.  相似文献   
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6.
The purpose of this study was to provide evidence on the fact that the observed decrease in EMG activity of the gastrocnemius medialis (GM) at pronounced knee flexed positions is not only due to GM insufficiency, by examining muscle fascicle lengths during maximal voluntary contractions at different positions. Twenty-two male long distance runners (body mass: 78.5+/-6.7 kg, height: 183+/-6 cm) participated in the study. The subjects performed isometric maximal voluntary plantar flexion contractions (MVC) of their left leg at six ankle-knee angle combinations. To examine the resultant ankle joint moments the kinematics of the left leg were recorded using a Vicon 624 system with 8 cameras operating at 120 Hz. The EMG activity of GM, gastrocnemius lateralis (GL), soleus (SOL) and tibialis anterior (TA) were measured using surface electromyography. Synchronously, fascicle length and pennation angle values of the GM were obtained at rest and at the plateau of the maximal plantar flexion using ultrasonography. The main findings were: (a) identifiable differences in fascicle length of the GM at rest do not necessarily imply that these differences would also exist during a maximal isometric plantar flexion contraction and (b) the EMG activity of the biarticular GM during the MVC decreased at a pronounced flexed knee-joint position (up to 110 degrees ) despite of no differences in GM fascicle length. It is suggested that the decrease in EMG activity of the GM at pronounced knee flexed positions is due to a critical force-length potential of all three muscles of the triceps surae.  相似文献   
7.

Background

Ethiopia has the largest cattle population in Africa. The vast majority of the national herd is of indigenous zebu cattle maintained in rural areas under extensive husbandry systems. However, in response to the increasing demand for milk products and the Ethiopian government''s efforts to improve productivity in the livestock sector, recent years have seen increased intensive husbandry settings holding exotic and cross breeds. This drive for increased productivity is however threatened by animal diseases that thrive under intensive settings, such as bovine tuberculosis (BTB), a disease that is already endemic in Ethiopia.

Methodology/Principal Findings

An extensive study was conducted to: estimate the prevalence of BTB in intensive dairy farms in central Ethiopia; identify associated risk factors; and characterize circulating strains of the causative agent, Mycobacterium bovis. The comparative intradermal tuberculin test (CIDT), questionnaire survey, post-mortem examination, bacteriology, and molecular typing were used to get a better understanding of the BTB prevalence among dairy farms in the study area. Based on the CIDT, our findings showed that around 30% of 2956 tested dairy cattle from 88 herds were positive for BTB while the herd prevalence was over 50%. Post-mortem examination revealed gross tuberculous lesions in 34/36 CIDT positive cattle and acid-fast bacilli were recovered from 31 animals. Molecular typing identified all isolates as M. bovis and further characterization by spoligotyping and MIRU-VNTR typing indicated low strain diversity within the study area.

Conclusions/Significance

This study showed an overall BTB herd prevalence of 50% in intensive dairy farms in Addis Ababa and surroundings, signalling an urgent need for intervention to control the disease and prevent zoonotic transmission of M. bovis to human populations consuming dairy products coming from these farms. It is suggested that government and policy makers should work together with stakeholders to design methods for the control of BTB in intensive farms in Ethiopia.  相似文献   
8.
Few randomized trials attempt to improve insulin sensitivity and associated metabolic risks in overweight Latino youth. The purpose of this study is to examine the effects of a modified carbohydrate nutrition program combined with strength training on insulin sensitivity, adiposity, and other type 2 diabetes risk factors in overweight Latino adolescents. In a 16‐week randomized trial, 54 overweight Latino adolescents (15.5 ± 1.0 years) were randomly assigned to: (i) Control (C; n = 16), (ii) Nutrition (N; n = 21), or (iii) Nutrition + Strength training (N+ST; n = 17). The N group received modified carbohydrate nutrition classes (once per week), while the N+ST received the same nutrition classes plus strength training (twice per week). The following were measured at pre‐ and postintervention: strength by 1‐repetition maximum, dietary intake by 3‐day records, body composition by dual‐energy X‐ray absorptiometry, glucose/insulin indices by oral glucose tolerance test (OGTT) and intravenous glucose tolerance test with minimal modeling. Across intervention group effects were tested using analysis of covariance with post hoc pairwise comparisons. A significant overall intervention effect was found for improvement in bench press (P < 0.001) and reductions in energy (P = 0.05), carbohydrate (P = 0.04) and fat intake (P = 0.03). There were no significant intervention effects on insulin sensitivity, body composition, or most glucose/insulin indices with the exception of glucose incremental area under the curve (IAUC) (P = 0.05), which decreased in the N and N+ST group by 18 and 6.3% compared to a 32% increase in the C group. In conclusion, this intense, culturally tailored intervention resulted in no significant intervention effects on measured risk factors with the exception of a beneficial effect on glycemic response to oral glucose.  相似文献   
9.
The aim of the study was to examine the external knee adduction moments in a group of older and younger adults while descending stairs and thus the possibility of an increased risk of knee osteoarthritis due to altered knee joint loading in the elderly. Twenty-seven older and 16 younger adults descended a purpose-built staircase. A motion capture system and a force plate were used to determine the subjects' 3D kinematics and ground reaction forces (GRF) during locomotion. Calculation of the leg kinematics and kinetics was done by means of a rigid, three-segment, 3D leg model. In the initial portion of the support phase, older adults showed a more medio-posterior GRF vector relative to the ankle joint, leading to lower ankle joint moments (P<0.05). At the knee, the older adults demonstrated a more medio-posterior directed GRF vector, increasing in knee flexion and adduction in the second part of the single support phase (P<0.05). Further, GRF magnitude was lower in the initial and higher in the mid-portions of the support phase for the elderly (P<0.05). The results show that older adults descend stairs by using the trailing leg before the initiation of the double support phase more compared to the younger ones. The consequence of this altered control strategy while stepping down is a more medially directed GRF vector increasing the magnitude of external knee adduction moment in the elderly. The observed changes between leading and trailing leg in the elderly may cause a redistribution of the mechanical load at the tibiofemoral joint, affecting the initiation and progression of knee osteoarthritis in the elderly.  相似文献   
10.
Innate immunity represents the first line of defense against invading pathogens in the respiratory tract. Innate immune cells such as monocytes, macrophages, dendritic cells, NK cells, and granulocytes contain specific pathogen-recognition molecules which induce the production of cytokines and subsequently activate the adaptive immune response. c-di-GMP is a ubiquitous second messenger that stimulates innate immunity and regulates biofilm formation, motility and virulence in a diverse range of bacterial species with potent immunomodulatory properties. In the present study, c-di-GMP was used to enhance the innate immune response against pertussis, a respiratory infection mainly caused by Bordetella pertussis. Intranasal treatment with c-di-GMP resulted in the induction of robust innate immune responses to infection with B. pertussis characterized by enhanced recruitment of neutrophils, macrophages, natural killer cells and dendritic cells. The immune responses were associated with an earlier and more vigorous expression of Th1-type cytokines, as well as an increase in the induction of nitric oxide in the lungs of treated animals, resulting in significant reduction of bacterial numbers in the lungs of infected mice. These results demonstrate that c-di-GMP is a potent innate immune stimulatory molecule that can be used to enhance protection against bacterial respiratory infections. In addition, our data suggest that priming of the innate immune system by c-di-GMP could further skew the immune response towards a Th1 type phenotype during subsequent infection. Thus, our data suggest that c-di-GMP might be useful as an adjuvant for the next generation of acellular pertussis vaccine to mount a more protective Th1 phenotype immune response, and also in other systems where a Th1 type immune response is required.  相似文献   
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