Antiracism defined as equitable sociocultural interactions in prekindergarten: Classroom racial composition makes a difference     

Stephanie M. Curenton  Shana E. Rochester  Jacqueline Sims  Nneka Ibekwe-Okafor  Iheoma U. Iruka  Arlene G. García-Miranda  Jessica Whittaker 《Child development》2022,93(3):681-698

This study used secondary data from the My Teaching Partner-Math/Science 2013–2016 randomized control trial to explore whether equitable sociocultural classroom interactions (see Curenton et al., 2019) were associated with the skills of 105 four- and five-year-olds (52% boys; drawn from 20 unique video recordings of preschool teachers/classrooms; 43% were Black, Latine, Asian, or other racially marginalized learners). Equitable interactions predicted children's skills with effect sizes ranging from small (0.01–0.44) to large (1.00). Moderation analyses revealed that when classrooms had more racially marginalized learners, teachers’ use of equitable disciplinary and personalized learning practices were associated with higher executive functioning gains across prekindergarten. Findings illustrate how classroom composition can be a key indicator between equitable classroom interactions and young children's early skills.  相似文献   

External quality assessment for the RIA of thyroid related hormones: Second phase     

Ajay Kumar  D. H. Shah  M. G. R. Rajan  U. R. Thakare  S. M. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):159-164

An external quality assessment was conducted to assess the performance of various laboratories for RIA of thhyroid related hormones in two phases. In the first phase thirty five laboratories participated. At the end of first phase a meeting cum workshop was organised to discuss the results of first phase, difficultires faced by the participants and pinpoint the short oming. A second phase was then initiated with an objective of improvement in the performance, if any, where twelve samples from four pools were distributed to twenty four laboratories who participated for the second phase. The overall return of the results increased significantly from 71.8% (1586/2208) for the first phase to 92.4% (732/792) for the second phase. The inter laboratory %CV for T₃, T₄ and TSH were lower during the second phase (30.6%, 19.0% and 31.6% respectively) as compared to those observed during first phase (36.3%, 22.7% and 52.8% respectively). Similarly, there was an improvement in reproducibility of ALTM as %CV for T₃, T₄ and TSH decreased from 6.0%, 9.8% and 13.4% respectively to 4.5%, 4.6% and 8.5% respectively. The individual performances of the participating laboratories viz. bias, variability of bias and imprecision also showed a trend towards improvement as percent laboratories having desirable or acceptable results for T₃, T₄ and TSH increased from 10.7%, 60.7% and 0.0% respectively to 20.8%, 66.7% and 22.2% respectively. External quality assessment thus appears to be beneficial in assessing the performane of a laboratory in comfparison with other laboratories and indeed helps in improving the performance.  相似文献   

Bond graphs for thermal energy transport and entropy flow     

Jean U. Thoma 《Journal of The Franklin Institute》1971

The transport of thermal energy in thermodynamics is described as the product of entropy flow and of the absolute temperature, in analogy to the volume flow and pressure in oil hydraulics and to electric charge flow (= current) and voltage in electronics. Bond graphs are shown to be especially suitable to describe the splitting of applied thermal energy into internal energy and external mechanical work. Transformers and the 0- and 1-junctions of Paynter can illustrate various entropy flow processes, including Carnot engines and heat exchangers. Entropy flow in heat conduction is distinguished from entropy convection, or transport by moving mass, where the entropy/temperature characteristic or equation of state is important. Irreversibilities are represented by impedance transformers reducing temperature and increasing entropy flow but conserving power.  相似文献   

Feasibility of determination of fertile period in Indian women based on urinary hormone estimations     

Meena Desai  U. M. Donde  M. Ikram Khatkhatay 《Indian journal of clinical biochemistry : IJCB》2001,16(1):127-131

Baseline data available on the excretory profiles of estrone giucuronide (E₁G), pregnanediol glucuronide (PdG) and luteinising hormone (LH) on human menstrual cycles (n=104) was retrospectively analysed for identifying the limits of fertile period (FP) to be used as natural method of family planning. The limits of fertile period are suggested based on centile distribution of E₁G and PdG levels during defined phase of menstrual cycle. Two approaches, which do not involve any mathematical calculation are suggested. In approach A, fertile period is said to have started when E₁G value of 35 ng/ml is reached and is said to have ended when the PdG value of 2 μg/ml on two consecutive days is obtained. The criteria were applied to 30 test cycles in whom authentic fertile period was identified based on excretory profiles of E₁G, PdG and LH throughout the menstrual cycles. When approach A was followed the authentic fertile period was covered in 27 cycles giving an accuracy of 90% with a mean fertile period length of 9.11+1.9 days. In approach B, the cut off limit of E₁G value was increased to 55 ng/ml in order to reduce the days of abstinence. Though the length of the fertile period was reduced to 7.2+1.5 days the accuracy of the approach was 66.6%. Thus the approach A which has accuracy of 90% may appeal to determined couples who wish to practice family planning by periodic abstinence or restrict the use of barrier methods.  相似文献   

Hopf bifurcation and synchronization of a five-dimensional self-exciting homopolar disc dynamo using a new fuzzy disturbance-observer-based terminal sliding mode control     

Zhouchao Wei  Amin Yousefpour  Hadi Jahanshahi  Uǧur Erkin Kocamaz  Irene Moroz 《Journal of The Franklin Institute》2021,358(1):814-833

Having found hidden hyperchaos in a 5D self-exciting homopolar disc dynamo, we study the existence of a Hopf bifurcation, which leads to unstable limit cycles bifurcating from a stable equilibrium. Hidden chaos with only stable equilibria can be observed from the Hopf bifurcation: a typical way to enable hidden attractors to be located. We then provide a new fuzzy controller, and a fast fuzzy disturbance observer, based on terminal sliding mode control for synchronization of the hyperchaotic system. Fuzzy inference is considered to weaken the chattering phenomena. Using Lyapunov stability theory, the stability of the closed-loop system is proved. Finally, simulations of synchronization are illustrated to show the efficient performance of the designed control method via external disturbances and dynamic uncertainties.  相似文献   

Neuromuscular control and running economy is preserved in elite international triathletes after cycling     

Bonacci J  Saunders PU  Alexander M  Blanch P  Vicenzino B 《Sports biomechanics / International Society of Biomechanics in Sports》2011,10(1):59-71

Running is the most important discipline for Olympic triathlon success. However, cycling impairs running muscle recruitment and performance in some highly trained triathletes; though it is not known if this occurs in elite international triathletes. The purpose of this study was to investigate the effect of cycling in two different protocols on running economy and neuromuscular control in elite international triathletes. Muscle recruitment and sagittal plane joint angles of the left lower extremity and running economy were compared between control (no preceding cycle) and transition (preceded by cycling) runs for two different cycle protocols (20-minute low-intensity and 50-minute high-intensity cycles) in seven elite international triathletes. Muscle recruitment and joint angles were not different between control and transition runs for either cycle protocols. Running economy was also not different between control and transition runs for the low-intensity (62.4 +/- 4.5 vs. 62.1 +/- 4.0 ml/min/kg, p > 0.05) and high-intensity (63.4 +/- 3.5 vs. 63.3 +/- 4.3 ml/min/kg, p > 0.05) cycle protocols. The results of this study demonstrate that both low- and high-intensity cycles do not adversely influence neuromuscular control and running economy in elite international triathletes.  相似文献   

Complex three-dimensional high aspect ratio microfluidic network manufactured in combined PerMX dry-resist and SU-8 technology     

Meier RCh  Badilita V  Brunne J  Wallrabe U  Korvink JG 《Biomicrofluidics》2011,5(3):34111-3411110

In this paper we present a new fabrication method that combines for the first time popular SU-8 technology and PerMX dry-photoresist lamination for the manufacturing of high aspect ratio three-dimensional multi-level microfluidic networks. The potential of this approach, which further benefits from wafer-level manufacturing and accurate alignment of fluidic levels, is demonstrated by a highly integrated three-level microfluidic chip. The hereby achieved network complexity, including 24 fluidic vias and 16 crossing points of three individual microchannels on less than 13 mm(2) chip area, is unique for SU-8 based fluidic networks. We further report on excellent process compatibility between SU-8 and PerMX dry-photoresist which results in high interlayer adhesion strength. The tight pressure sealing of a fluidic channel (0.5 MPa for 1 h) is demonstrated for 150 μm narrow SU-8/PerMX bonding interfaces.  相似文献   

Algorithmic thinking development through physical computing activities with Arduino in STEM education     

Sarı  Uğur  Pektaş  Hüseyin Miraç  Şen  Ömer Faruk  Çelik  Harun 《Education and Information Technologies》2022,27(5):6669-6689

Education and Information Technologies - The need to benefit from information technologies in the twenty-first century digital age is increasing in all economies to overcome problems and...  相似文献   

The dissection room experience: A factor in the choice of organ and whole body donation—A Nigerian survey          下载免费PDF全文

Emeka G. Anyanwu  Emmanuel N. Obikili  Augustine U. Agu 《Anatomical sciences education》2014,7(1):56-63

The psychosocial impact of human dissection on the lives of medical and health science students has been noted. To assess the impact of the dissection room experience on one's willingness to become a whole body and organ donor, the attitudes of 1,350 students and professionals from the medical, health, and non‐health related disciplines to body and organ donation were studied. The participants were broken into categories according to degree of exposure to human dissection. Participants who were never exposed to the dissection experience showed more willingness to donate their bodies than those who were exposed. With the exception of the physiotherapy department, the students and professionals from the health science departments who were exposed to the dissection room but never engaged in dissection showed the most unwillingness to donate their bodies (P < 0.001). An unwillingness to donate oneself was noted as one of the negative impacts associated with exposure to the dissection room. Willingness to donate an organ correlated positively with the level of exposure to the dissection room (P < 0.001). Most of the reasons for unwillingness were traceable to negative perceptions of the dissection room as a result of poor and disrespectful management of the human cadavers. Anat Sci Educ. 7: 56–63. © 2013 American Association of Anatomists.  相似文献   

Literatur-Neuerscheinungen     

U. Mohr 《Sportwissenschaft》1976,6(3):345-346

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