排序方式： 共有28条查询结果，搜索用时 25 毫秒
21.
Ann C. Miller Nancy Rumaldo Guadalupe Soplapuco Alicia Condeso Betsy Kammerer Shannon Lundy Fabiola Faiffer Andy Montañez Karen Ramos Naysha Rojas Carmen Contreras Maribel Muñoz Hilda Valdivia Daojing Vilca Nandy Córdova Patricia Hilario Martha Vibbert Leonid Lecca Sonya Shin 《Child development》2021,92(6):e1275-e1289
This study is a randomized controlled trial of a 12-week community-based group parenting intervention (“CASITA”) in Lima, Peru. CASITA improved neurodevelopment in a pilot study of 60 Peruvian children and subsequently scaled to 3,000 households throughout the district. The objective of this study was to assess intervention effectiveness when implemented at scale. A total of 347 children ages 6–20 months (52.7% male, 100% identified as “mestizo”) at risk for developmental difficulties were randomized to immediate or delayed CASITA. At 3 months after enrollment, the immediate arm showed significantly higher overall development, based on the Extended Ages and Stages Questionnaire and Home Observation for Measurement of the Environment scores (Cohen’s ds = .36 and .31, respectively). Programs demonstrably effective at scale could help address children’s development risks worldwide. 相似文献
22.
Dirt absorption on the ski running surface — quantification and influence on the gliding ability 总被引：2，自引：2，他引：0
We propose a thesis that minimising dirt on the running surface of skis improves the surface glide. Waxing usually improves the gliding ability of skis in the short term. But how does waxing affect pollution absorption in the long term? In this study a number of skis with a transparent base and a white background were treated by steel scraping and with different glide waxes. The gliding ability of waxed and unwaxed skis, the sliding surface whiteness and the hydrophobicity were tested and documented. Tests were performed before and after the skis had been used for different distances. It was observed that all the waxed skis (regardless of the wax used) absorbed more dirt than unwaxed, and as a result all waxed skis lose their glide ability sooner than unwaxed (freshly scraped) skis in wet snow conditions. 相似文献
23.
Xiaowei Li Kejun Feng Long Li Lu Yang Xiaoshu Pan Hoda Safari Yazd Cheng Cui Juan Li Leonid Moroz Yujia Sun Bang Wang Xiang Li Tong Huang Weihong Tan 《国家科学评论(英文版)》2020,7(12):1933
Lipid–oligonucleotide conjugates (LONs) are powerful molecular-engineering materials for various applications ranging from biosensors to biomedicine. Their unique amphiphilic structures enable the self-assembly and the conveyance of information with high fidelity. In particular, LONs present remarkable potential in measuring cellular mechanical forces and monitoring cell behaviors. LONs are also essential sensing tools for intracellular imaging and have been employed in developing cell-surface-anchored DNA nanostructures for biomimetic-engineering studies. When incorporating therapeutic oligonucleotides or small-molecule drugs, LONs hold promise for targeted therapy. Moreover, LONs mediate the controllable assembly and fusion of vesicles based on DNA-strand displacements, contributing to nanoreactor construction and macromolecule delivery. In this review, we will summarize the general synthesis strategies of LONs, provide some characterization analysis and emphasize recent advances in bioanalytical and biomedical applications. We will also consider the relevant challenges and suggest future directions for building better functional LONs in nanotechnology and materials-science applications. 相似文献
24.
Leonid Suschenya 《Higher Education in Europe》1995,20(4):42-49
The work and the prospects of the Belarussian Academy of Sciences are described. The Academy, like other institutions in Belarus, has suffered greatly since the period of transition began in 1990. The Academy and its constituent institutes are struggling to continue providing their traditional leadership in regard to basic and applied research in all disciplines. In some areas, particularly in the hard sciences, Belarussian researchers continue to chalk up internationally recognized successes; however, the size of the research staff in the republic has declined by 50 per cent since 1990, and there is difficulty in recruiting new blood. The basic problem is one of finance; however, the Academy is trying to tap several sources of funding including the government. It is also taking steps to influence the training of young scientists and academics and to forge links with the Academies of other countries. At all costs, Belarus must not lose its scientific potential. 相似文献
25.
Alejandra Ferreira de Loza Manuel Jimenez-Lizarraga Leonid Fridman 《Journal of The Franklin Institute》2012,349(4):1416-1429
This paper tackles the problem of a two-player differential game affected by matched uncertainties with only the output measurement available for each player. We suggest a state estimation based on the so-called algebraic hierarchical observer for each player in order to design the Nash equilibrium strategies based on such estimation. At the same time, the use of an output integral sliding mode term (also based on the estimation processes) for the Nash strategies robustification for both players ensures the compensation of the matched uncertainties. A simulation example shows the feasibility of this approach in a magnetic levitator problem. 相似文献
26.
The aim of this research was to examine the relationship between exposure to classroom noise and the psychological well-being
of full-time teaching staff in 14 preschool settings located across Western Sydney. The participants comprised 25 teachers,
each of whom was administered a range of instruments. The results indicated that 40% of teachers were subjected to daily or
peak noise exposures beyond the maximum permissible levels according to the Australian Occupational Health and Safety (OH&S)
standard. Further, the unique contribution of daily noise dose received by the staff to the prediction of their vocational
strain, interpersonal strain, and defensive functioning was evident through multiple regression analyses. It was concluded
that vocational strain amongst preschool teachers may be related, in part, to a combination of elevated daily doses of noise,
and years of teaching experience. 相似文献
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The principal contribution of this note is to avoid the parametric resonance effect and attenuate the payload oscillations in an overhead-crane system subject to periodic variations in the base support. Considering an appropriate sliding output with relative degree one, we present the sliding mode control design based on the Super-Twisting Algorithm (STA), ensuring finite time convergence to the desired sliding surface for the linear periodic system with Lipschitz continuous matched and unmatched uncertainties bounded together by their gradients by known functions. The suggested approach also provides chattering phenomenon attenuation. Obtained results are verified experimentally. 相似文献