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91.
Jun Won Kim Bung-Nyun Kim Johanna Inhyang Kim Young Sik Lee Kyung Joon Min Hyun-Jin Kim Jaewon Lee 《PloS one》2015,10(11)
Introduction
Social network analysis has emerged as a promising tool in modern social psychology. This method can be used to examine friend-based social relationships in terms of network theory, with nodes representing individual students and ties representing relationships between students (e.g., friendships and kinships). Using social network analysis, we investigated whether greater severity of ADHD symptoms is correlated with weaker peer relationships among elementary school students.Methods
A total of 562 sixth-graders from two elementary schools (300 males) provided the names of their best friends (maximum 10 names). Their teachers rated each student’s ADHD symptoms using an ADHD rating scale.Results
The results showed that 10.2% of the students were at high risk for ADHD. Significant group differences were observed between the high-risk students and other students in two of the three network parameters (degree, centrality and closeness) used to assess friendship quality, with the high-risk group showing significantly lower values of degree and closeness compared to the other students. Moreover, negative correlations were found between the ADHD rating and two social network analysis parameters.Conclusion
Our findings suggest that the severity of ADHD symptoms is strongly correlated with the quality of social and interpersonal relationships in students with ADHD symptoms. 相似文献92.
93.
94.
Joon Sang Lee 《Journal of Plant Biology》2010,53(1):19-23
Stomata usually open when leaves are transferred from darkness to light. However, reverse-phase stomatal opening in succulent
plants has been known. CAM plants such as cacti and Opuntia ficus–indica achieve their high water use efficiency by opening their stomata during the cool, desert nights and closing them during the
hot, dry days. Signal transduction pathway for stomatal opening by blue light photoreceptors including phototropins and the
carotenoid pigment zeaxanthin has been suggested. Blue light regulated signal transduction pathway on stomatal opening could
not be applied to CAM plants, but the most possible theory for a nocturnal response of stomata in CAM plants is photoperiodic
circadian rhythm. 相似文献
95.
Autotrophic and heterotrophic respiration in needle fir and Quercus-dominated stands in a cool-temperate forest, central Korea 总被引:3,自引:0,他引:3
Na-yeon Lee Jin-Woo Koo Nam Jin Noh Joon Kim Yowhan Son 《Journal of plant research》2010,123(4):485-495
To investigate annual variation in soil respiration (R
S) and its components [autotrophic (R
A) and heterotrophic (R
H)] in relation to seasonal changes in soil temperature (ST) and soil water content (SWC) in an Abies holophylla stand (stand A) and a Quercus-dominated stand (stand Q), we set up trenched plots and measured R
S, ST and SWC for 2 years. The mean annual rate of R
S was 436 mg CO2 m−2 h−1, ranging from 76 to 1,170 mg CO2 m−2 h−1, in stand A and 376 mg CO2 m−2 h−1, ranging from 82 to 1,133 mg CO2 m−2 h−1, in stand Q. A significant relationship between R
S and its components and ST was observed over the 2 years in both stands, whereas a significant correlation between R
A and SWC was detected only in stand Q. On average over the 2 years, R
A accounted for approximately 34% (range 17–67%) and 31% (15–82%) of the variation in R
S in stands A and Q, respectively. Our results suggested that vegetation type did not significantly affect the annual mean
contributions of R
A or R
H, but did affect the pattern of seasonal change in the contribution of R
A to R
S. 相似文献
96.
97.
Alexey Rivkin Sean P. Ahearn Stephanie M. Chichetti Christopher L. Hamblett Yudith Garcia Michelle Martinez Jed L. Hubbs Michael H. Reutershan Matthew H. Daniels Phieng Siliphaivanh Karin M. Otte Chaomin Li Andrew Rosenau Laura M. Surdi Joon Jung Bethany L. Hughes Jamie L. Crispino George N. Nikov Richard E. Middleton Christopher M. Moxham Mark S. Shearman 《Bioorganic & medicinal chemistry letters》2010,20(7):2279-2282
The development of a novel series of purines as γ-secretase modulators for potential use in the treatment of Alzheimer’s disease is disclosed herein. Optimization of a previously disclosed pyrimidine series afforded a series of potent purine-based γ-secretase modulators with 300- to 2000-fold in vitro selectivity over inhibition of Notch cleavage and that selectively reduces Αβ42 in an APP-YAC transgenic mouse model. 相似文献
98.
99.
Xuefei Tan Richland W. Tester Gregory R. Luedtke Sarvajit Chakravarty Babu J. Mavunkel John J. Perumattam Qing Lu Imad Nashashibi Joon Jung Jie Hu Albert Liclican Ramona Almirez Jocelyn Tabora Vinh Tran Maureen Laney Daniel E. Levy Sundeep Dugar 《Bioorganic & medicinal chemistry letters》2010,20(3):828-831
Derivatives of the 4-fluorobenzyl dimethylpiperazine-indole class of p38α MAP kinase inhibitors are described. Biological evaluation of these compounds focused on maintaining activity while improving pharmacokinetic (PK) properties. Improved properties were observed for structures bearing substitutions on the benzylic methylene. 相似文献
100.
Gigun Lee Kwanwoo You Taesam Kang Kwang Joon Yoon Jeong Oog Lee Jung Keun Park 《仿生工程学报(英文版)》2010,7(2):168-174
<正> We proposed a dynamic model identification and design of an H-Infinity (i.e.H_∞) controller using a LightweightPiezo-Composite Actuator (LIPCA).A second-order dynamic model was obtained by using input and output data, and applyingan identification algorithm.The identified model coincides well with the real LIPCA.To reduce the resonating mode that istypical of piezoelectric actuators, a notch filter was used.A feedback controller using the H_∞ control scheme was designed basedon the identified dynamic model; thus, the LIPCA can be easily used as an actuator for biomemetic applications such as artificialmuscles or macro/micro positioning in bioengineering.The control algorithm was implemented using a microprocessor, analogfilters, and power amplifying drivers.Our simulation and experimental results demonstrate that the proposed control algorithmworks well in real environment, providing robust performance and stability with uncertain disturbances. 相似文献