Validity, Reliability, and Usefulness of My Jump 2 App for Measuring Vertical Jump in Primary School Children

There is a persistent need in sport science for developing a measuring tool that is affordable, portable, and easy to use. We aimed to examine the concurrent validity and test-retest reliability of the My Jump 2 app compared to a validated OptoJump instrument for measuring jump performance during the squat jump (SJ), countermovement jump (CMJ), and CMJ free arms (CMJAM) in primary school children. A total of 48 participants (11-14 years age), volunteered to participate in this research. The jumps were recorded with a validated OptoJump photoelectric cell system and a concurrent device (iPhone X through My Jump 2 app) at the same time. The participants repeated the testing procedure after two weeks to assess the reliability of the measurements (ICC). Systematic bias between sessions and tools was evaluated using the paired samples t-test and Bland and Altman analysis. High test-retest reliability (ICC > 0.89) was observed for all measures' in-between conditions. Very large correlations in the total sample were observed between the My Jump 2 app and OptoJump for SJ (r = 0.97, p = 0.001), CMJ (r = 0.97, p = 0.001), and CMJAM (r = 0.99, p = 0.001). Bland and Altman's plot depicting limits of agreement for the total sample between the OptoJump and My Jump 2 show that the majority of data points are within the 95% CIs. The results of this study suggest that My Jump 2 is a valid, reliable, and useful tool for measuring jump performance in primary school children

Feasibility and Performance of the Microwave Thermal Rocket Launcher

Beamed-energy launch concepts employing a microwave thermal thruster are feasible in principle, and microwave sources of sufficient power to launch tons into LEO already exist. Microwave thermal thrusters operate on an analogous principle to nuclear thermal thrusters, which have experimentally demonstrated specific impulses exceeding 850 seconds. Assuming such performance, simple application of the rocket equation suggests that payload fractions of 10% are possible for a single stage to orbit (SSTO) microwave thermal rocket. We present an SSTO concept employing a scaled X-33 aeroshell. The flat aeroshell underside is covered by a thin-layer microwave absorbent heat-exchanger that forms part of the thruster. During ascent, the heat-exchanger faces the microwave beam. A simple ascent trajectory analysis incorporating X-33 aerodynamic data predicts a 10% payload fraction for a 1 ton craft of this type. In contrast, the Saturn V had 3 non-reusable stages and achieved a payload fraction of 4%

Productive characteristics of four maternal lines of rabbit

The objective of this study was to compare litter size traits and kindling interval in four Spanish maternal lines of rabbit (A, V, H y LP) selected for litter size at weaning. At the origin, line V had a higher litter size (total, alive, weaned and marketed) than line A. Also, LP and H lines had higher litter sizes than line A.Ragab Ghanem, MM. (2009). Productive characteristics of four maternal lines of rabbit. http://hdl.handle.net/10251/14404Archivo delegad

Collagens in avian neural crest development: distribution in vivo and migration-promoting ability in vitro

This study examines the spatiotemporal distribution of collagen (Col) types I-V and IX during neural crest development in vivo and their ability to support neural crest cell movement in vitro. Col I, III and IV were widespread throughout the embryo, including the neural crest migratory pathways, whereas Col II, V and IX preferentially localized to regions from which migrating neural crest cells were absent. Col I-IV and IX occurred both in association with basement membranes and within interstitial matrices, whereas Col V only was detected in juxtaposition to basement membranes. Although initially distributed throughout the rostrocaudal extent of the somitic sclerotome, Col I and III rearranged to the caudal portion with progressive neural crest cell migration through the rostral portion of the sclerotome. This rearrangement does not occur in neural crest-ablated embryos, suggesting that it is a direct consequence of neural crest cell migration. The perinotochordal matrix, avoided by neural crest cells, contained a metameric Col II/IX immunoreactivity along the rostrocaudal axis which alternated with that of Col I and III. In contrast, Col IV and V were not observed in this matrix, but lined the basement membranes of the notochord and ventrolateral neural tube. To determine their functional significance for neural crest cell migration in vivo, purified collagens were tested for their ability to promote neural crest cell motility in vitro. Neural crest cell migration on isolated collagens was most pronounced on Col I and IV, whereas Col II, V and the triple-helical fragment of Col VII were unable to support cell motility. Substrata created by copolymerization of Col I and fibronectin, or Col I and laminin-nidogen, supported cell motility better than Col I alone, whereas both Col V and a cartilage-type chondroitin sulfate proteoglycan reduced cell movement on Col I. Fibronectin bound to pre-immobilized monomeric Col I, II or V had a reduced ability to support neural crest cell movement when compared to fibronectin alone. A similar reduction was seen for Col IV bound to the low density heparan sulfate proteoglycan from the EHS mouse tumor. The results demonstrate that Col I-IX are differentially distributed in the early avian embryo. During neural crest development several of these collagens undergo dynamic reorganizations that correlate with the migration of neural crest cells. Furthermore, various collagens possess distinct abilities to support neural crest cell migration in vitro, and their migration-promoting activity can be modulated by their conformation and/or association with other matrix components

The Willingness to Pay for Beach Scenery and its Preservation in Italy

In order to understand the multiple values of landscape, this paper suggests an evaluative methodology that takes into account a quantitative approach, public opinion, and an economic estimation. This study analyzes the coastal scenery of 40 Italian beaches using a fuzzy logic and a Contingent Valuation (CV). Each site was classified into five categories: Class I beaches were littorals with high natural settings; Class II sites were natural and semiurban beaches having low influences by anthropic structures; Classes III, IV, and V had lower evaluations due to poor physical and human condition. A questionnaire survey analyzed beach users’ preferences, judgment, and Willingness to Pay (WTP). Results suggest that landscape judgment is directly correlated to scenery assessment; therefore, beaches of Class I and II were judged beautiful while beaches of Class IV and V had poor judgments. Similarly, the importance given to the landscape was highest in Class I and II than in the others. WTP for the conservation of the selected beaches was about €16 per season. Our findings suggest that people are disposed to pay more for a beach with the top-grade of scenery (Class I and II) and low grade of urbanization. Moreover, WTP would rise for females and for nonresident users with an academic degree, which appreciated the coastal landscape

Reconsidering the evidence on returns to T&V extension in Kenya

The authors revisit the widely disseminated results of a study (Bindlish and Evenson 1993, 1997) of the impact of the training and visit (T&V) system of management for public extension services in Kenya. T&V was introduced in Kenya by the World Bank and has since been supported through two successive projects. The impact of the projects continues to be the subject of much debate. The authors'paper suggests the need for greater vigilance in empirical analysis, especially about the quality of data used to support Bank policy and the need to validate potentially influential findings. Using household data from 1990, Bindlish and Evenson found the returns from extension to be very high. But the authors find that the returns estimated by Binslish and Evenson suffer from data errors, and limitations imposed by cross-sectional data. After correcting for several data processing and measurement errors, the authors show the results to be less robust than reported by Bindlish and Evenson and highly sensitive to regional effects. When region-specific effects are included, a positive return to extension cannot be established, using Bindlish and Evenson's data set and cross-sectional model specifications. After testing the robustness of results using a number of tests, the authors could not definitively establish the factors underlying strong regional effects, largely because of the limitations imposed by the cross-sectional framework. Household panel data methods would have allowed greater control for regional effects and would have yielded better insight into the impact of extension. The impact on agricultural productivity in Kenya expected from T&V extension services is not discernible from the available data, and the impact may vary across districts. The hypothesis that T&V had no impact in Kenya between 1982 and 1990 cannot be rejected. The sample data fail to support a positive rate of return on the investment in T&V.Agricultural Knowledge&Information Systems,Statistical&Mathematical Sciences,Environmental Economics&Policies,Labor Policies,Economic Theory&Research,Economic Theory&Research,Health Economics&Finance,Agricultural Knowledge&Information Systems,Environmental Economics&Policies,Statistical&Mathematical Sciences

Cluster Analysis of Maize Inbred Lines

The determination of diversity among inbred lines is important for heterosis breeding. Sixty maize inbred lines were evaluated for their eight agro morphological traits during winter season of 2011 to analyze their genetic diversity. Clustering was done by average linkage method. The inbred lines were grouped into six clusters. Inbred lines grouped into Clusters II had taller plants with maximum number of leaves. The cluster III was characterized with shorter plants with minimum number of leaves. The inbred lines categorized into cluster V had early flowering whereas the group into cluster VI had late flowering time. The inbred lines grouped into the cluster III were characterized by higher value of anthesis silking interval (ASI) and those of cluster VI had lower value of ASI. These results showed that the inbred lines having widely divergent clusters can be utilized in hybrid breeding programme

FRACTURE ENERGY OF ILLITIC RAMMED EARTH WITH HIGH WATER-CLAY RATIO

The article is focused on design of mixture of rammed earth, producing, testing and determination of fracture energy of unfired rammed earth and its stress-strain curve in tensile bending test. Three different mixtures of rammed earth were designed and tested. The amount of water and binder is one of the key properties of the rammed earth, the amount of the water is expressed by the water-clay ratio. Mechanical properties of the earth material highly depend on the composition of sand, clay and water. The prescription AGL III with 80 % of sand, 20 % of clay and 0.400 water-clay ratio reached the maximum value of fracture energy 4.858±0.002 J/m2 and set AGL V had the minimum value 1.934±0.310 J/m2

Hrabianki Szembekówny - pionierki archeologii wielkopolskiej z przełomu XIX i XX wieku

Archaeological interests of the Szembek earls from Siemianice near Kępno (southern Wielkopolska) have spread over many generations starting from the middle of the 19th century until the present time. This is well exemplified by activities of Jadwiga (1883-1939) and Zofia (1884-1974) Szembek. In the years 1897-1908, both sisters undertook systematic and model excavations of the multicultural cemetery (-ies) at Siemianice near Kępno (Bronze Age 11, Bronze Age V - HaD; the Late La Téne - Early Roman Iron Age) and cemetery at Lipie near Kępno (Bronze Age V). Jadwiga Szembek excavated also multicultural settlement at Tarnowica near Jaworów (western Ukraine) in 1924 and 1927. An origin and development of archaeological interests of the Szembek sisters, along with a detailed analysis of their field works, was reconstructed on the basis of unpublished archive materials and old literature of the subject. Assessment of their achievements in this field, according to both previous and current criteria, made possible to support opinion by Prof. Józef Kostrzewski who rated the Szembek sisters among archaeologists of the most outstanding merit before 1918.Archaeological interests of the Szembek earls from Siemianice near Kępno (southern Wielkopolska) have spread over many generations starting from the middle of the 19th century until the present time. This is well exemplified by activities of Jadwiga (1883-1939) and Zofia (1884-1974) Szembek. In the years 1897-1908, both sisters undertook systematic and model excavations of the multicultural cemetery (-ies) at Siemianice near Kępno (Bronze Age 11, Bronze Age V - HaD; the Late La Téne - Early Roman Iron Age) and cemetery at Lipie near Kępno (Bronze Age V). Jadwiga Szembek excavated also multicultural settlement at Tarnowica near Jaworów (western Ukraine) in 1924 and 1927. An origin and development of archaeological interests of the Szembek sisters, along with a detailed analysis of their field works, was reconstructed on the basis of unpublished archive materials and old literature of the subject. Assessment of their achievements in this field, according to both previous and current criteria, made possible to support opinion by Prof. Józef Kostrzewski who rated the Szembek sisters among archaeologists of the most outstanding merit before 1918

Genetic divergence studies for yield and quality traits in high protein landraces of rice (Oryza sativa L.)

The present study was undertaken to study the extent of genetic diversity in high protein rice landraces with respect to yield, yield components and quality characters. In this direction, 30 high protein rice landraces, collected from different parts of country by ICAR-Indian Institute of Rice Research (ICAR-IIRR), Hyderabad along with the high protein check, CR DHAN 310 were evaluated during Kharif 2021 at ICAR-IIRR farm located at International Crops Research Institute of Semi Arid Tropics (ICRISAT), Hyderabad. The study examined the genetic divergence of high protein rice cultures for yield, quality and nutritional parameters. Multivariate analysis techniques of Mahalanobis D2 and Principal Component Analysis (PCA) were used to estimate the genetic diversity in the experimental material. In Mahalanobis D2, the 31 high protein rice cultures were divided into six clusters. Cluster I had highest number of rice cultures (19), followed by Cluster III and V with five, four cultures, respectively. The clusters, II, IV, VI were mono-genotypic. It was discovered that grouping of these cultures into several clusters was random and was not related to geographical diversity. Inter-cluster distances between clusters V and VI were maximum. Cluster V had also exhibited higher intra-cluster distance. Further, Cluster VI had showed maximum yield plant-1, grains per panicle-1, zinc content and test weight, while, Cluster V had recorded high protein content. The greatest contribution to genetic divergence was recorded by yield plant-1 (21.60%), followed by iron (10.54%) and zinc content (9.54%). In Principal Component Analysis, the first five Principal Components (PCs) with eigen values >1 accounted for cumulative contribution of 67.69% to the total variability. The three traits, yield plant-1, iron content, and amylose content contributed the most to variability. The 2D scatter diagram exhibited 18 different clusters, out of which 11 clusters were mono-genotypic. Mahalanobis D2 Statistic and PCA concluded maximum genetic diversity between the landraces, JAK 248-3 and JAK 638 with JAK 611