ASSESSING SEDIMENT REGIME ALTERATION OF THE LOWER DRAVA RIVER

Alterations to the sediment regime of the lower Drava River were assessed using the rescaled adjusted partial sums (RAPS) method and possible causes of these changes are discussed in this paper. The sudden alteration to sediment regime and the sharp decreases of suspended sediment concentration (SSC) at the two gauging stations in the lower Drava River began in the 1980s. Suspended sediment load decreased about 65% between 1967–1981 (0.922×106 t/year) and 2003–2017 (0.323×106 t/year) for the Botovo station. For the Donji Miholjac station, suspended sediment load decreased about 81% between 1971–1981 (1.383×106 t/year) and 2007–2017 (0.263×106 t/year). The construction and operation of reservoirs were the main reasons for these sharp alterations. SSC and flow discharge (Q) relationships were assessed by proposing a new form of a sediment rating curve (SRC). Compared with the traditional SRC approach, the new form of the SRC can better capture seasonal dynamics of SSC at daily and monthly time-scales

Tracking Energy Balance in Adolescents: Levels of Compliance, Energy Flux, and Learning

Background/Objective: Advancing knowledge about energy balance (EB) is important for helping to reverse the obesity epidemic in many modern societies. This study examined adolescents\u27 experience and perception of using an objective self-monitoring tool (SenseWear armband; SWA) and a portable diet journal to track EB for 7 days. Methods: Forty-five 6th grade students in a midwestern state of the United States [Caucasian: n = 34, 76%; age: 11.7 ± 1.8 years; body mass index (BMI): 20.84 ± 3.94] participated in the study. The SWA, diet journal, and semistructured individual interview were used to measure energy expenditure (EE) and physical activity (PA), energy intake (EI), and perception of the experience, respectively. Mixed methods were used to analyze quantitative and qualitative data. Results: It was found that the participants were physically active over the week (moderate-to-vigorous PA: 218.06 ± 26.50 minutes per day). Both SWA (% of wearing time: 85 ± 5%) and diet journal (days of using: 5.58 ± 2.15 days), especially the latter, were found to be under-used. A conceptual model depicting the adolescents\u27 experience and perception was established based on the results. Conclusion: The study indicates that the majority of adolescents were able to effectively use the SWA and the diet journal to track EB over time. Qualitative observations revealed that tracking EI and EE with these tools provided a valuable, experiential way for youth to learn about EB. The findings support the continued exploration of self-monitoring EB for promoting knowledge and awareness about EB among adolescents

Evaluation of a Concept-Based Physical Education Unit for Energy Balance Education

Background: Physical education (PE) is a key channel that impacts children’s decisions and behaviors for healthful living. This study evaluated the effects of a concept-based PE (CBPE) instructional unit, featured by energy balance (EB) education, on students’ knowledge learning, situational interest, cognitive, and physical engagements as well as teachers’ perceptions. Methods: Fourth and 5th grade students (n = 468) in a mid-western state of the United States were recruited as the participants. Four elementary schools were randomized to the CBPE or control groups. Students’ EB knowledge, situational interest, cognitive engagement, and physical engagement were measured by a knowledge test, the Situational Interest Scale—Elementary, written task sheets, and accelerometers, respectively, while teachers’ perceptions of the CBPE unit were captured by individual interviews at the end of the experiment. Results: The CBPE group showed a significant increase in EB knowledge, while the control did not. Both groups showed a similar increasing trend for situational interest over time, although the statistical results favored the control group. For physical engagement, the CBPE group demonstrated a statistically different but substantively similar level of in-class physical activity compared to the control group. The CBPE group also showed a moderate level of cognitive engagement throughout the unit. The PE teachers reported overall positive perceptions about teaching the CBPE unit. Conclusion: These results support the utility of the CBPE unit in enhancing EB education along with facilitating positive student interest and engagement as well as positive teaching experiences

Electron Bunch Train Excited Higher-Order Modes in a Superconducting RF Cavity

Higher-order mode (HOM) based intra-cavity beam diagnostics has been proved effectively and conveniently in superconducting radio-frequency (SRF) accelerators. Our recent research shows that the beam harmonics in the bunch train excited HOM spectrum, which have much higher signal-to-noise ratio than the intrinsic HOM peaks, may also be useful for beam diagnostics. In this paper, we will present our study on bunch train excited HOMs, including the theoretic model and recent experiments carried out based on the DC-SRF photoinjector and SRF linac at Peking University.Comment: Supported by National Natural Science Foundation of China (11275014

Learners\u27 Motivational Response to the Science, PE, & Me! Curriculum: A Situational Interest Perspective

Background: The Science, PE, & Me! (SPEM) curriculum is a concept-based physical education curriculum that offers students coherent educational experiences for constructing health-related fitness knowledge through movement experiences. The purpose of this study was to evaluate students’ motivational response to the SPEM curriculum from the situational interest perspective. Methods: The study used a cluster randomized controlled design in which 30 elementary schools in one of the largest metropolitan areas in the eastern United States were randomly assigned to an experimental or comparison condition. Although all students in the 3rd, 4th, and 5th grades in the targeted schools were eligible to participate in the study, a random sample of students from the experimental (n = 1749; 15 schools) and comparison groups (n = 1985; 15 schools) provided data. Students’ motivational response to the SPEM curriculum or comparison curriculum was measured using the previously validated Situational Interest Scale Elementary. Data were analyzed using structural mean modeling. Results: The results demonstrated that the experimental group (as reference group) showed significantly higher enjoyment (z = 2.01), challenge (z = 6.54), exploration (z = 12.195), novelty (z = 8.80), and attention demand (z = 7.90) than the comparison group. Conclusion: The findings indicate that the SPEM curriculum created a more situationally interesting context for learning than the comparison physical education curriculum

Using Sensewear Armband and Diet Journal to Promote Adolescents\u27 Energy Balance Knowledge and Motivation

Purpose: Educating adolescents about energy balance (EB) is essential for effective weight control. This study utilized the Sensewear (SWA) armband and a diet journal to promote adolescents\u27 EB knowledge and motivation. Methods: Ninety sixth graders were randomly assigned into the experimental group (n = 46) who utilized SWA and diet journal for 7 consecutive days or the control group (n = 44) who did not. Both groups were pre-and post-measured on EB knowledge, situational interest, and weight. The experimental group was tracked on motivation effort, energy expenditure (EE), and energy intake (EI). Results: EB knowledge significantly increased and situational interest remained stable (except for total interest and enjoyment) over time, but these changes did not favor the experimental group. Situational interest and motivation effort were correlated with EE, EI, and/or EB. Conclusion: Tracking EB using the SWA and diet journal is motivating but has limited efficacy in promoting adolescents\u27 EB knowledge. Using these two tools as educational technology in conjunction with a focused, systematic, and educational approach has the potential to leverage adolescents\u27 EB knowledge, motivation, as well as behaviors for living an energy-balanced lifestyle

Effects of water level fluctuation on thermal stratification in a typical tributary bay of Three Gorges Reservoir, China

Xiangxi River is a typical tributary of Three Gorges Reservoir (TGR) in China. Based on field observations in 2010, thermal stratification was significant in most months of the year. Through field data analysis and numerical simulations, the seasonal and spatial variation of thermal stratification as related to the impact of the operation of TGR were investigated. Thermal stratification was most pronounced from April to September in the Xiangxi River tributary. Air temperature (AT) and water level (WL) were the two dominant variables impacting thermal stratification. AT affected the surface water temperature promoting the formation of thermal stratification, and high WLs in TGR deepened the thermocline depth and thermocline bottom depth. These results provide a preliminary description of the seasonal variation and spatial distribution of thermal stratification, which is important for better understanding how thermal stratification affects algae blooms in Xiangxi River

Establishment of noncycloplegic methods for screening myopia and pre-myopia in preschool children

PurposePre-myopia, a non-myopic refractive state, is a key concern for myopia prevention because of its association with a significantly higher risk of myopia in children under 3 years of age. Amid the myopia pandemic, its onset at younger ages is increasing, yet research on screening methods for myopia and pre-myopia in preschool children remains limited. This study aimed to establish effective noncycloplegic screening methods for myopia and pre-myopia in preschool children.MethodsThis cross-sectional study included 16 kindergartens in Shanghai, China. Uncorrected distance visual acuity (UDVA) was recorded using a logMAR visual acuity chart. Pre- and post-cycloplegic refractions were obtained using an auto-refractor (TopconKR-800). Noncycloplegic axial length (AL) and corneal curvature radius (CR) were measured using the IOL Master-700. Logistic regression models were developed to establish accurate noncycloplegic screening methods for myopia and pre-myopia.ResultsA total of 1,308 children with a mean age of 4.3 ± 0.9 years were included; among them 640 (48.9%) were girls. The myopia prevalence rate was 2.8% (n = 36), and the prevalence of pre-myopia was 21.9% (n = 286). Pre-myopia screening (cycloplegic spherical equivalent [SE] ≤ −0.5 < SE ≤0.75 diopters [D]) using UDVA exhibited an area under the receiver operating curve (AUC) of 0.52, noncycloplegic SE had an AUC of 0.70 and AL had an AUC of 0.63. The accuracy of combining the SE and AL/CR ratio was among the best with the least number of checks used, and the AUC was 0.74 for pre-myopia screening and 0.94 for myopia screening (cycloplegic SE ≤ −0.5 D). The addition of UDVA did not further improve the accuracy.ConclusionUsing UDVA alone did not achieve good accuracy in pre-myopia or myopia screening of young children. Under non-cycloplegic conditions, the combination of AL/CR and SE demonstrated favorable results for pre-myopia and myopia screening of preschool children