1,011 research outputs found

    Attitudes and Perceptions toward Affirmative Action Programs: An Application of Institutional Theory

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    Due to the continuing controversy surrounding the use of affirmative action programs in organizational hiring and promotion practices, we conducted a study to model individualsā€™ attitudes, beliefs, and perceptions toward affirmative action (AA) programs considering social influences and an institutional theory framework. To conduct the study we surveyed 413 managers and supervisors from three large hotel companies in the pacific western and southeastern United States. Results indicate that institutional and social forces positively influenced participantsā€™ general perceptions of AA in the workplace. Influences from social interaction exhibited a negative relationship upon attitudes toward the experience and practice of AA, specifically related to AA hires and organizational issues stemming from AA rather than the legislation itself

    Optimal set of grid size and angular increment for practical dose calculation using the dynamic conformal arc technique: a systematic evaluation of the dosimetric effects in lung stereotactic body radiation therapy

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    Purpose To recommend the optimal plan parameter set of grid size and angular increment for dose calculations in treatment planning for lung stereotactic body radiation therapy (SBRT) using dynamic conformal arc therapy (DCAT) considering both accuracy and computational efficiency. Materials and methods Dose variations with varying grid sizes (2, 3, and 4 mm) and angular increments (2Ā°, 4Ā°, 6Ā°, and 10Ā°) were analyzed in a thorax phantom for 3 spherical target volumes and in 9 patient cases. A 2-mm grid size and 2Ā° angular increment are assumed sufficient to serve as reference values. The dosimetric effect was evaluated using doseā€“volume histograms, monitor units (MUs), and dose to organs at risk (OARs) for a definite volume corresponding to the doseā€“volume constraint in lung SBRT. The times required for dose calculations using each parameter set were compared for clinical practicality. Results Larger grid sizes caused a dose increase to the structures and required higher MUs to achieve the target coverage. The discrete beam arrangements at each angular increment led to over- and under-estimated OARs doses due to the undulating dose distribution. When a 2Ā° angular increment was used in both studies, a 4-mm grid size changed the dose variation by up to 3ā€“4% (50 cGy) for the heart and the spinal cord, while a 3-mm grid size produced a dose difference of \u3c1% (12 cGy) in all tested OARs. When a 3-mm grid size was employed, angular increments of 6Ā° and 10Ā° caused maximum dose variations of 3% (23 cGy) and 10% (61 cGy) in the spinal cord, respectively, while a 4Ā° increment resulted in a dose difference of \u3c1% (8 cGy) in all cases except for that of one patient. The 3-mm grid size and 4Ā° angular increment enabled a 78% savings in computation time without making any critical sacrifices to dose accuracy. Conclusions A parameter set with a 3-mm grid size and a 4Ā° angular increment is found to be appropriate for predicting patient dose distributions with a dose difference below 1% while reducing the computation time by more than half for lung SBRT using DCAT

    Reciprocal Relationship Between Depression and Internet Gaming Disorder in Children: A 12-month Follow-Up of the iCURE Study Using Cross-Lagged Path Analysis

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    Objectives: Previous studies have reported an association between Internet gaming disorder (IGD) and depression, but the directionality of the relationship remains unclear. Therefore, we examined the reciprocal relationship between level of depressive symptoms and IGD among children in a longitudinal study. Methods: Research panels for this study consisted of 366 elementary-school students in the iCURE study. All participants were current Internet users, so they could be considered an at-risk population for IGD. Self-reported severity of IGD features and level of depression were assessed by the Internet Game Use-Elicited Symptom Screen and Childrenā€™s Depression Inventory, respectively. Follow-up assessment was completed after 12Ā months. We fitted cross-lagged structural equation models to investigate the association between the two variables at two time points contemporaneously. Results: The cross-lagged analysis revealed that level of depression at baseline significantly predicted severity of IGD features at the 12-month follow-up (Ī²ā€‰=ā€‰0.15, pā€‰=ā€‰.003). Severity of IGD features at baseline also significantly predicted level of depression at the 12-month follow-up (Ī²ā€‰=ā€‰0.11, pā€‰=ā€‰.018), controlling for possible confounding factors. Conclusions: The cross-lagged path analysis indicates a reciprocal relationship between severity of IGD features and level of depressive symptoms. Understanding the reciprocal relationship between depressive symptoms and severity of IGD features can assist in interventions to prevent both conditions. These findings provide theoretical support for prevention and remediation plans for IGD and depressive symptoms among children

    PD-1 deficiency protects experimental colitis via alteration of gut microbiota

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    Programmed cell death-1 (PD-1) is a coinhibitory molecule and plays a pivotal role in immune regulation. Here, we demonstrate a role for PD-1 in pathogenesis of inflammatory bowel disease (IBD). Wild-type (WT) mice had severe wasting disease during experimentally induced colitis, while mice deficient for PD-1 (PD-1(-/-)) did not develop colon inflammation. Interestingly, PD-1(-/-) mice cohoused with WT mice became susceptible to colitis, suggesting that resistance of PD-1(-/-) mice to colitis is dependent on their gut microbiota. 16S rRNA gene-pyrosequencing analysis showed that PD-1(-/-) mice had altered composition of gut microbiota with significant reduction in Rikenellaceae family. These altered colon bacteria of PD-1(-/-) mice induced less amount of inflammatory mediators from colon epithelial cells, including interleukin (IL)-6, and inflammatory chemokines. Taken together, our study indicates that PD-1 expression is involved in the resistance to experimental colitis through altered bacterial communities of colon.112Ysciescopuskc

    Manipulation of Rat Movement via Nigrostriatal Stimulation Controlled by Human Visually Evoked Potentials

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    Here, we report that the development of a brain-to-brain interface (BBI) system that enables a human user to manipulate rat movement without any previous training. In our model, the remotely-guided rats (known as ratbots) successfully navigated a T-maze via contralateral turning behaviour induced by electrical stimulation of the nigrostriatal (NS) pathway by a brain-computer interface (BCI) based on the human controller's steady-state visually evoked potentials (SSVEPs). The system allowed human participants to manipulate rat movement with an average success rate of 82.2% and at an average rat speed of approximately 1.9 m/min. The ratbots had no directional preference, showing average success rates of 81.1% and 83.3% for the left-and right-turning task, respectively. This is the first study to demonstrate the use of NS stimulation for developing a highly stable ratbot that does not require previous training, and is the first instance of a training-free BBI for rat navigation. The results of this study will facilitate the development of borderless communication between human and untrained animals, which could not only improve the understanding of animals in humans, but also allow untrained animals to more effectively provide humans with information obtained with their superior perception.11Ysciescopu

    Exploratory, cognitive, and depressive-like behaviors in adult and pediatric mice exposed to controlled cortical impact

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    Objective Sequelae of behavioral impairments associated with human traumatic brain injury (TBI) include neurobehavioral problems. We compared exploratory, cognitive, and depressive-like behaviors in pediatric and adult male mice exposed to controlled cortical impact (CCI). Methods Pediatric (21 to 25 days old) and adult (8 to 12 weeks old) male C57Bl/6 mice underwent CCI at a 2-mm depth of deflection. Hematoxylin and eosin staining was performed 3 to 7 days after recovery from CCI, and injury volume was analyzed using ImageJ. Neurobehavioral characterization after CCI was performed using the Barnes maze test (BMT), passive avoidance test, open-field test, light/dark test, tail suspension test, and rotarod test. Acutely and subacutely (3 and 7 days after CCI, respectively), CCI mice showed graded injury compared to sham mice for all analyzed deflection depths. Results Time-dependent differences in injury volume were noted between 3 and 7 days following 2-mm TBI in adult mice. In the BMT, 2-mm TBI adults showed spatial memory deficits compared to sham adults (P<0.05). However, no difference in spatial learning and memory was found between sham and 2-mm CCI groups among pediatric mice. The open-field test, light/dark test, and tail suspension test did not reveal differences in anxiety-like behaviors in both age groups. Conclusion Our findings revealed a graded injury response in both age groups. The BMT was an efficient cognitive test for assessing spatial/non-spatial learning following CCI in adult mice; however, spatial learning impairments in pediatric mice could not be assessed

    Depression and suicide risk prediction models using blood-derived multi-omics data

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    More than 300 million people worldwide experience depression; annually, ~800,000 people die by suicide. Unfortunately, conventional interview-based diagnosis is insufficient to accurately predict a psychiatric status. We developed machine learning models to predict depression and suicide risk using blood methylome and transcriptome data from 56 suicide attempters (SAs), 39 patients with major depressive disorder (MDD), and 87 healthy controls. Our random forest classifiers showed accuracies of 92.6% in distinguishing SAs from MDD patients, 87.3% in distinguishing MDD patients from controls, and 86.7% in distinguishing SAs from controls. We also developed regression models for predicting psychiatric scales with R2 values of 0.961 and 0.943 for Hamilton Rating Scale for Depression???17 and Scale for Suicide Ideation, respectively. Multi-omics data were used to construct psychiatric status prediction models for improved mental health treatment

    Inhibitory Effects of Cytosolic Ca 2+

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    Intracellular Ca2+ ([Ca2+]i) is platelet aggregation-inducing molecule and is involved in activation of aggregation associated molecules. This study was carried out to understand the Ca2+-antagonistic effect of ginsenoside Ro (G-Ro), an oleanane-type saponin in Panax ginseng. G-Ro, without affecting leakage of lactate dehydrogenase, dose-dependently inhibited thrombin-induced platelet aggregation, and the half maximal inhibitory concentration was approximately 155ā€‰Ī¼M. G-Ro inhibited strongly thrombin-elevated [Ca2+]i, which was strongly increased by A-kinase inhibitor Rp-8-Br-cAMPS compared to G-kinase inhibitor Rp-8-Br-cGMPS. G-Ro increased the level of cAMP and subsequently elevated the phosphorylation of inositol 1, 4, 5-triphosphate receptor I (IP3RI) (Ser1756) to inhibit [Ca2+]i mobilization in thrombin-induced platelet aggregation. Phosphorylation of IP3RI (Ser1756) by G-Ro was decreased by PKA inhibitor Rp-8-Br-cAMPS. In addition, G-Ro inhibited thrombin-induced phosphorylation of ERK 2 (42ā€‰kDa), indicating inhibition of Ca2+ influx across plasma membrane. We demonstrate that G-Ro upregulates cAMP-dependent IP3RI (Ser1756) phosphorylation and downregulates phosphorylation of ERK 2 (42ā€‰kDa) to decrease thrombin-elevated [Ca2+]i, which contributes to inhibition of ATP and serotonin release, and p-selectin expression. These results indicate that G-Ro in Panax ginseng is a beneficial novel Ca2+-antagonistic compound and may prevent platelet aggregation-mediated thrombotic disease
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