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61.
1. The effect of propionate on lipid synthesis in lymphocytes cultured for 24 hr and incubated for 2 hr was investigated. 2. [1-14C]-propionate was incorporated mainly into phospholipids in both control and concanavalin A (Con A) stimulated cultured lymphocytes. 3. The content of free coenzyme A markedly decreased in 2 hr incubated lymphocytes when propionate was added to the medium at concentrations from 10 to 100 mmol/l. 4. Propionate at 40 mmol/l decreased the incorporation of [1-14C]-palmitate into phospholipids (86%), triacylglycerol (87%) and cholesterol ester (98%) and increased in cholesterol (133%) of cultured lymphocytes. 5. Addition of propionate into the culture medium at 2.5 and 5.0 mmol/l concentrations markedly increased the activity of hydrolases of various acylCoA derivatives. 6. The results suggest that propionate may reduce the content of acylCoA and so its esterification and this might be important for the regulation of lymphocytes proliferation.  相似文献   
62.
1. The present study examines the effect of leptin on glucose transport and metabolism in incubated soleus muscle from male lean albino rats. 2. Insulin (100 microU/ml) increased glucose uptake by twofold while the leptin group (100 nmol/l) reached 75% of the insulin response after 1 hr of incubation. However, leptin did not potentiate the insulin effect on glucose uptake in soleus muscle. 3. Leptin elicited a significant increase (27.7%) in total lactate production, accompanied by a three-fold increment in glycogen synthesis from [U-14C]D-glucose. 4. Insulin raised glycogen synthesis by sixfold. The leptin plus insulin group increased glycogen synthesis by eightfold, which is equivalent to the sum of the separated leptin and insulin groups. 5. Leptin per se exerts an insulin-like effect stimulating glucose uptake, glycogen synthesis, and lactate formation and also seems to potentiate the effect of insulin on glucose incorporation into glycogen in incubated soleus muscle.  相似文献   
63.
Thiobarbituric acid reactant substances (TBARs) content, and the activities of glucose-6-phosphate dehydrogenase (G6PDh), citrate synthase (CS), Cu/Zn- and Mn-superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPX) were measured in the lymphoid organs (thymus, spleen, and mesenteric lymph nodes (MLN)) and skeletal muscles (gastrocnemius and soleus) of adrenodemedullated (ADM) rats. The results were compared with those obtained for sham-operated rats. TBARs content was reduced by adrenodemedullation in the lymphoid organs (MLN) (28%), thymus (40%) and spleen (42%)) and gastrocnemius muscle (67%). G6PDh activity was enhanced in the MLN (69%) and reduced in the spleen (28%) and soleus muscle (75%). CS activity was reduced in all tissues (MLN (75%), spleen (71%), gastrocnemius (61%) and soleus (43%)), except in the thymus which displayed an increment of 56%. Cu/Zn-SOD activity was increased in the MLN (126%), thymus (223%), spleen (80%) and gastrocnemius muscle (360%) and was reduced in the soleus muscle (31%). Mn-SOD activity was decreased in the MLN (67%) and spleen (26%) and increased in the thymus (142%), whereas catalase activity was reduced in the MLN (76%), thymus (54%) and soleus muscle (47%). It is particularly noteworthy that in ADM rats the activity of glutathione peroxidase was not detectable by the method used. These data are consistent with the possibility that epinephrine might play a role in the oxidative stress of the lymphoid organs. Whether this fact represents an important mechanism for the establishment of impaired immune function during stress remains to be elucidated.  相似文献   
64.
Occlusions and binocular stereo   总被引:10,自引:2,他引:8  
Binocular stereo is the process of obtaining depth information from a pair of cameras. In the past, stereo algorithms have had problems at occlusions and have tended to fail there (though sometimes post-processing has been added to mitigate the worst effects). We show that, on the contrary, occlusions can help stereo computation by providing cues for depth discontinuities.We describe a theory for stereo based on the Bayesian approach, using adaptive windows and a prior weak smoothness constraint, which incorporates occlusion. Our model assumes that a disparity discontinuity, along the epipolar line, in one eyealways corresponds to an occluded region in the other eye thus, leading to anocclusion constraint. This constraint restricts the space of possible disparity values, thereby simplifying the computations. An estimation of the disparity at occluded features is also discussed in light of psychophysical experiments. Using dynamic programming we can find the optimal solution to our system and the experimental results are good and support the assumptions made by the model.  相似文献   
65.
The present study carries out measurements and evaluations of whole‐body vibration (WBV) exposure in drivers of a cargo vehicle composition, traveling under different conditions of roads and loading, to compare and assess the health risk through the various criteria provided by vibration exposure standards. Using the acceleration data measured in the seat, the WBV exposure of the drivers is evaluated according to the criteria provided by five standards: three different versions of ISO 2631 (Part 1, 1985 and 1997; Part 5, 2004), the European Directive 2002/44/EC and the new Brazilian regulation NR‐15 published in 2014. Comparisons investigating the differences between the standards are presented. The results of the experimental data indicate that the current version of the NR‐15 is more restrictive than the other standards considered in this paper. Thus, these results can contribute to improve the criteria used in the new NR‐15.  相似文献   
66.

In recent years, the phenomenon of eSports has been a growing trend and consequently, in addition to players, other groups of users, including coaches and analysts, took an interest in online video games and the data extracted from them. Among many types of video games, one of the most widely played is the MOBA (Multiplayer Online Battle Arena) League of Legend (LoL) game. Similary to traditional sports, players and coaches/analysts analyse all game events, such as, players’ movements, to understand how they play to define new strategies and improve their performance. Our main goal is to get a better understanding of which visualizations techniques are more adequate to handle this type of spatio-temporal information data, associated to player performance analysis in video games. To address this goal, we inquired players to identify the analytical questions they need to support for performance analysis and designed the VisuaLeague prototype for the visualization of in-game player trajectories, using animated maps, and events during a LoL match. This paper presents a user study to evaluate the adequacy of animated maps and the analytical strategies followed by players when using spatio-temporal data to analyse player performance. The results support the adequacy of using the animated maps technique to convey information to users in this context. Moreover, they also point out towards a high degree of importance given to the spatio-temporal components of the data for player performance analysis.

  相似文献   
67.
This paper presents a control algorithm for reducing heat losses caused by clouds in large solar fields. The formulation is based on a Mixed Logical Dynamical (MLD) representation of the solar field plus the application of a Practical Nonlinear Model Predictive Controller (PNMPC) for calculating the optimal control action. The main purpose of the controller is to deactivate fields with inlet temperature greater than outlet temperature and to manipulate the oil flow rate of the activated fields for tracking the reference of the outlet temperature. A simplified lumped parameters model is used for prediction and simulation of the solar fields.  相似文献   
68.
We propose and evaluate a system for content-based visualization and exploration of music collections. The system is based on a modification of Kohonen’s Self-Organizing Map algorithm and allows users to choose the locations of clusters containing acoustically similar tracks on the music space. A user study conducted to evaluate the system shows that the possibility of personalizing the music space was perceived as difficult. Conversely, the user study and objective metrics derived from users’ interactions with the interface demonstrate that the proposed system helped individuals create playlists faster and, under some circumstances, more effectively. We believe that personalized browsing interfaces are an important area of research in Multimedia Information Retrieval, and both the system and user study contribute to the growing work in this field.  相似文献   
69.
Software and Systems Modeling - In recent years, there has been a growing interest in the use of reference conceptual models to capture information about complex and sensitive business domains...  相似文献   
70.
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