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81.
A seven channel polystyrene (PS) microchip has been constructed using a micromilling machine and a high-temperature assembling. Protein A (PA) has been immobilized by a passive sorption on the microchannel walls. Two bioaffinity assays with human immunoglobulin G (hIgG) as a ligand have been carried out. (i) PA as the receptor and fluorescently labeled hIgG (FITC-hIgG) as the ligand, (ii) PA as the receptor with hIgG as the quantified ligand and fluorescently labeled goat anti-human IgG (FITC-gIgG) as the secondary ligand. One incubation step of the assays took only 5 min instead of hours typical for enzyme-linked immunosorbent assay applications. Calibration curves of the dependence of a fluorescence signal on the hIgG concentration in a sample have been obtained in one step due to a parallel arrangement of microchannels. A mathematical model of the PA-FITC-hIgG complex formation in the chip has been developed. The values of the kinetic constant of the PA-FITC-hIgG binding (kon=5.5 m3 mol−1 s−1) and the equilibrium dissociation constant of the formed complex (Kd≤3×10−6 mol m−3) have been obtained by fitting to experimental data. The proposed microchip enables fast evaluation of kinetic and equilibrium constants of ligand-receptor bioaffinity pairs and the ligand quantification. As the use of microfluidic chips for immunoassays is often limited by price, we used procedures and chemicals that allow for an inexpensive construction and operation of the microdevice, e.g., temperature assembling as a fabrication technique, detection via an ordinary digital camera, nonspecific polystyrene as a substrate, passive sorption of biomolecules as an immobilization technique, etc. 相似文献
82.
As the American population continues to become more diverse there is a need to provide children in early education with factual information about all ethnic groups to decrease prejudice. First, teachers must examine their own beliefs prior to implementing a multicultural approach into the curriculum. Three questions are presented that will assist teachers in evaluating their views and behaviors toward ethnic groups. Informative resources are provided for teachers to educate themselves, parents, and students. Through children's literature, instructional materials, and Internet sources, teachers can promote more positive attitudes among students and educate children to be respectful and accept the individuality of others. 相似文献
83.
Treatment practices for childhood posttraumatic stress disorder 总被引:4,自引:0,他引:4
OBJECTIVE: This study surveyed practices in treating childhood PTSD among child psychiatrists and non-M.D. therapists with self-identified interest in treating traumatized children. METHOD: An anonymous survey was mailed to 207 child psychiatrists ("medical") and 460 nonphysician ("non-medical") therapists inquiring about current interventions used to treat children with PTSD. RESULTS: Two hundred and forty-seven responses were received: of 77 medical and 82 nonmedical respondents who currently treat children with PTSD, a wide variety of modalities are used. Most preferred modalities among medical responders were pharmacotherapy, psychodynamic, and cognitive-behavioral therapy. Most preferred modalities among nonmedical respondents were cognitive-behavioral, family, and nondirective play therapy. Ninety-five percent of medical respondents used pharmacotherapy for this disorder; most preferred medications to treat childhood PTSD were selective serotonin reuptake inhibitors and alpha-adrenergic agonists. Several significant differences between medical and nonmedical practices were identified. CONCLUSIONS: There is little clinical consensus regarding the effectiveness of the many modalities used to treat traumatized children who have PTSD symptoms; empirical research is particularly needed to evaluate the efficacy of pharmacotherapy and EMDR. 相似文献
84.
Priscilla Savopoulos Stephanie Brown Peter J. Anderson Deirdre Gartland Christina Bryant Rebecca Giallo 《Child development》2022,93(4):e396-e411
The cognitive functioning of children who experience intimate partner violence (IPV) has received less attention than their emotional-behavioral outcomes. Drawing upon data from 615 (48.4% female) 10-year-old Australian-born children and their mothers (9.6% of mothers born in non-English speaking countries) participating in a community-based longitudinal study between 2004 and 2016, this study examined the associations between IPV in infancy and cognition in middle childhood (at age 10). Results showed that IPV in the first 12 months of life was associated with lower general cognitive ability and poorer executive attention but not working memory skills. IPV in middle childhood (in the 10th year postpartum) was not associated with cognition. This study provides evidence for the long-term impact of early life exposure to IPV on children's cognition, and points to the importance of early intervention to optimize development. 相似文献
85.
Instructional Science - Digital drawing can foster learning, but only if the drawing is of sufficient quality. Hence, the focus of the present study was to investigate whether and how two types of... 相似文献
86.
Lavoué Elise Kazemitabar Maedeh Doleck Tenzin Lajoie Susanne P. Carrillo Rubiela Molinari Gaëlle 《Educational technology research and development : ETR & D》2020,68(1):269-292
Educational technology research and development - This paper studies learners’ emotion awareness in university level academic contexts as a first step to help learners regulate their... 相似文献
87.
Yuen Mantak Chung Y. B. Lee Queenie A. Y. Lau Patrick S. Y. Chan Raymond M. C. Gysbers Norman C. Shea Peter M. K. 《International Journal for Educational and Vocational Guidance》2020,20(3):653-676
International Journal for Educational and Vocational Guidance - This study provides insights into how Chinese adolescents in Hong Kong interpret the concept of “meaning in life.” Data... 相似文献
88.
Magdalena M. Apanasionok Richard P. Hastings Corinna F. Grindle Richard C. Watkins Andreas Paris 《科学教学研究杂志》2019,56(7):847-880
A comprehensive review of the literature was conducted to identify current practice on teaching science to students with intellectual disability (ID) and/or Autism Spectrum Disorder (ASD) in relation to two review questions—students' science outcomes and students' and teachers' experiences of the interventions. Six databases related to education, psychology, and science were systematically searched. A detailed protocol can be viewed on PROSPERO (registration number: CRD42017057323). Thirty studies were identified that reported on science interventions and 20 on student/teacher experiences of the interventions. The majority of the studies targeted science vocabulary and concepts. Other targets included inquiry skills and comprehension skills. The majority of the interventions used components of systematic instruction (n = 23). Five studies focused on self-directed learning and two on comprehension-based instruction. Students and teachers reported positive experiences of the interventions. The findings suggest that components of systematic instruction in particular might be effective in teaching science content to students with ID and/or ASD. Further research is needed to explore the effectiveness of identified interventions on teaching more complex science skills and with students with severe disabilities. Some limitations related to the search strategy are highlighted. 相似文献
89.
90.
Hae Yeon Lee Jeremy P. Jamieson Adriana S. Miu Robert A. Josephs David S. Yeager 《Child development》2019,90(6):e849-e867
Grades often decline during the high school transition, creating stress. The present research integrates the biopsychosocial model of challenge and threat with the implicit theories model to understand who shows maladaptive stress responses. A diary study measured declines in grades in the first few months of high school: salivary cortisol (N = 360 students, N = 3,045 observations) and daily stress appraisals (N = 499 students, N = 3,854 observations). Students who reported an entity theory of intelligence (i.e., the belief that intelligence is fixed) showed higher cortisol when grades were declining. Moreover, daily academic stressors showed a different lingering effect on the next day's cortisol for those with different implicit theories. Findings support a process model through which beliefs affect biological stress responses during difficult adolescent transitions. 相似文献