4,449 research outputs found
Statistical regularities across trials bias attentional selection
Previous studies have shown that attentional selection can be biased toward locations that are likely to contain a target and away from locations that are likely to contain a distractor. It is assumed that through statistical learning, participants are able to extract the regularities in the display, which in turn biases attentional selection. The present study employed the additional singleton task to examine the ability of participants to extract regularities that occurred across trials. In four experiments, we found that participants were capable of picking up statistical regularities concerning target positions across trials both in the absence and presence of distracting information. It is concluded that through statistical learning, participants are able to extract intertrial statistical associations regarding subsequent target location, which in turn biases attentional selection. We argue here that the weights within the spatial priority map can be dynamically adapted from trial to trial such that the selection of a target at a particular location increases the weights of the upcoming target location within the spatial priority map, giving rise to a more efficient target selection
Adeno-associated virus serotype rh.10 displays strong muscle tropism following intraperitoneal delivery
Recombinant adeno-associated virus (rAAV) is an attractive tool for basic science and translational medicine including gene therapy, due to the versatility in its cell and organ transduction. Previous work indicates that rAAV transduction patterns are highly dependent on route of administration. Based on this relationship, we hypothesized that intraperitoneal (IP) administration of rAAV produces unique patterns of tissue tropism. To test this hypothesis, we investigated the transduction efficiency of 12 rAAV serotypes carrying an enhanced green fluorescent protein (EGFP) reporter gene in a panel of 12 organs after IP injection. Our data suggest that IP administration emphasizes transduction patterns that are different from previously reported intravascular delivery methods. Using this approach, rAAV efficiently transduces the liver, pancreas, skeletal muscle, heart and diaphragm without causing significant histopathological changes. Of note, rAAVrh.10 showed excellent muscle transduction following IP administration, highlighting its potential as a new muscle-targeting vector
Relationship between neonatal dacryocystitis and cesarean section and the treatment of neonatal dacryocystitis
AIM: To explore the treatment of neonatal dacryocystitis of different ages and the relationship between caesarean section and neonatal dacryocystitis.<p>METHODS: A total of 260 cases(260 eyes)of children with neonatal dacryocystitis were divided into 1-3 months group, 4-6 months group, 7-12 months group and 13-24 months group, Each group was respectively given the lacrimal sac massage, lacrimal passage irrigation and probing of lacrimal passage method. Curative effect of each method was observed in different groups. Analysis was made to determine whether caesarean section was the cause of neonatal dacryocystitis.<p>RESULTS: The comparison between 1-3 months group and 4-6 months group showed significant difference(<i>χ</i><sup>2</sup>=19.89, <i>P</i><0.05). Lacrimal sac massage was effective for babies under 6 months, particularly in 1-3 months babies. The curative effect of lacrimal passage irrigation in four groups was compared, and there was statistical significance in the difference between the curative effect of each group(<i>χ</i><sup>2</sup>=54.95, <i>P</i><0.05). The difference between the 1-3 months group and 4-6 months group was <i>χ</i><sup>2</sup>=0.00003, <i>P</i>>0.05, lacrimal passage irrigation of these two groups showed no significant difference in efficacy. The comparison result between the other two groups showed no significant difference(<i>P</i><0.05), lacrimal passage irrigation effects are different from each group. The comparison result between 7-12 months group and 13-24 months group was <i>χ</i><sup>2</sup>=10.29, <i>P</i><0.05. Infants born by cesarean section accounted for 85% of all cases. <p>CONCLUSION:Lacrimal sac massage can exert very good therapeutic effects in infants less than 3 months. The curative effects of irrigation of lacrimal passage are quite good in babies under 12 months. Probing of lacrimal passage has a good curative effect in 7-12 months infants, but a poor curative effect in babies over 12 months. Caesarean section is an important cause for neonatal dacryocystitis
Nonparametric and semi-parametric panel data models: recent developments
ABSTRACT: In this paper, we provide an intensive review of the recent developments for semiparametric and fully nonparametric panel data models that are linearly separable in the innovation and the individual-specific term. We analyze these developments under two alternative model specifications: fixed and random effects panel data models. More precisely, in the random effects setting, we focus our attention in the analysis of some efficiency issues that have to do with the so-called working independence condition. This assumption is introduced when estimating the asymptotic variance-covariance matrix of nonparametric estimators. In the fixed effects setting, to cope with the so-called incidental parameters problem, we consider two different estimation approaches: profiling techniques and differencing methods. Furthermore, we are also interested in the endogeneity problem and how instrumental variables are used in this context. In Addition, for practitioners, we also show different ways of avoiding the so-called curse of dimensionality problem in pure nonparametric models. In this way, semiparametric and additive models appear as a solution when the number of explanatory variables is large
1,2-Bis(1,3-dithiol-2-ylidene)hydrazine
The title molecule, C6H4N2S4, has a crystallographically imposed centre of symmetry located at the mid-point of the N—N single bond. The molecule is essentially planar: the two five-membered rings form a dihedral angle of 0.17 (6)°. The crystal packing exhibits short intermolecular S⋯S contacts of 3.549 (2) Å
Blood Pressure Reduction Combining Baroreflex Restoration for Stroke Prevention in Hypertension in Rats
Blood pressure reduction is an important and effective strategy in stroke prevention in hypertensives. Recently, we found that baroreflex restoration was also crucial in stroke prevention. The present work was designed to test the hypothesis that a combination of blood pressure reduction and baroreflex restoration may be a new strategy for stroke prevention. In Experiment 1, the effects of ketanserin (0.3, 1, 3, 10 mg/kg), amlodipine (0.3, 1, 2, 3 mg/kg) and their combination (1 + 0.3, 1 + 1, 1 + 2, 1 + 3 mg/kg) on blood pressure and baroreflex sensitivity (BRS) of stroke-prone spontaneously hypertensive rats (SHR-SP) were determined under conscious state. It was found that both amlodipine and ketanserin decreased blood pressure dose-dependently. Ketanserin enfanced BRS from a very small dose but amlodipine enfanced BRS only at largest dose used. At the dose of 1 + 2 mg/kg (ketanserin + amlodipine), the combination possessed the largest synergism on blood pressure reduction. In Experiments 2 and 3, SHR-SP and two-kidney, two-clip (2K2C) renovascular hypertensive rats received life-long treatments with ketanserin (1 mg/kg) and amlodipine (2 mg/kg) or their combination (0.5 + 1, 1 + 2, 2 + 4 mg/kg). The survival time was recorded and the brain lesion was examined. It was found that all kinds of treatments prolonged the survival time of SHR-SP and 2K2C rats. The combination possessed a significantly better effect on stroke prevention than mono-therapies. In conclusion, combination of blood pressure reduction and baroreflex restoration may be a new strategy for the prevention of stroke in hypertension
Recommended from our members
Dietary Intake of Fatty Acids, Total Cholesterol, and Stomach Cancer in a Chinese Population.
To investigate the associations between dietary fatty acids and cholesterol consumption and stomach cancer (SC), we analyzed data from a population-based case-control study with a total of 1900 SC cases and 6532 controls. Dietary data and other risk or protective factors were collected by face-to-face interviews in Jiangsu Province, China, from 2003 to 2010. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multiple unconditional logistic regression models and an energy-adjusted method. The joint associations between dietary factors and known risk factors on SC were examined. We observed positive associations between dietary saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and total cholesterol and the development of SC, comparing the highest versus lowest quarters. Increased intakes of dietary SFAs (p-trend = 0.005; aOR, 1.11; 95% CI, 1.01-1.22 with a 7 g/day increase as a continuous variable) and total cholesterol (p-trend < 0.001; aOR, 1.13; 95% CI, 1.06-1.22 with a 250 mg/day increase as a continuous variable) were monotonically associated with elevated odds of developing SC. Our results indicate that dietary SFAs, MUFAs, and total cholesterol are associated with stomach cancer, which might provide a potential dietary intervention for stomach cancer prevention
Raw Garlic Consumption and Risk of Liver Cancer: A Population-Based Case-Control Study in Eastern China.
Although the major risk factors for liver cancer have been established, preventive factors for liver cancer have not been fully explored. We evaluated the association between raw garlic consumption and liver cancer in a large population-based case-control study in Eastern China. The study was conducted in Jiangsu, China, from 2003 to 2010. A total of 2011 incident liver cancer cases and 7933 randomly selected population-controls were interviewed. Epidemiological data including raw garlic intake and other exposures were collected, and serum markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection were assayed. Overall, eating raw garlic twice or more per week was inversely associated with liver cancer, with an adjusted odds ratio (aOR) of 0.77 (95% confidence interval (CI): 0.62-0.96) compared to those ingesting no raw garlic or less than twice per week. In stratified analyses, high intake of raw garlic was inversely associated with liver cancer among Hepatitis B surface antigen (HBsAg) negative individuals, frequent alcohol drinkers, those having history of eating mold-contaminated food or drinking raw water, and those without family history of liver cancer. Marginal interactions on an additive scale were observed between low raw garlic intake and HBsAg positivity (attributable proportion due to interaction (AP) = 0.31, 95% CI: -0.01-0.62) and heavy alcohol drinking (AP = 0.28, 95% CI: 0.00-0.57). Raw garlic consumption is inversely associated with liver cancer. Such an association shed some light on the potential etiologic role of garlic intake on liver cancer, which in turn might provide a possible dietary intervention to reduce liver cancer in Chinese population
Expressions of Neuregulin 1β and ErbB4 in Prefrontal Cortex and Hippocampus of a Rat Schizophrenia Model Induced by Chronic MK-801 Administration
Recent human genetic studies and postmortem brain examinations of schizophrenia patients strongly indicate that dysregulation of NRG1 and ErbB4 may be important pathogenic factors of schizophrenia. However, this hypothesis has not been validated and fully investigated in animal models of schizophrenia. In this study we quantitatively examined NRG1 and ErbB4 protein expressions by immunohistochemistry and Western blot in the brain of a rat schizophrenia model induced by chronic administration of MK-801 (a noncompetitive NMDA receptor antagonist). Our data showed that NRG1β and ErbB4 expressions were significantly increased in the rat prefrontal cortex and hippocampus but in different subregions. These findings suggest that altered expressions of NRG1 and ErbB4 might be attributed to the schizophrenia. Further study in the role and mechanism of NRG1 and ErbB4 may lead to better understanding of the pathophysiology for this disorder
- …