bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Biomechanical Analysis of the Effects of Bouncing the Barbell in the Conventional Deadlift
Authors: Krajewski Kellen T. , LeFavi Robert G. , Riemann Bryan L. 
Published: February 2018

Abstract
Krajewski, K, LeFavi, R, and Riemann, B. A biomechanical analysis of the effects of bouncing the barbell in the conventional deadlift. J Strength Cond Res 33(7S): S70–S77, 2019—The purpose of this study is to analyze biomechanical differences between the bounce and pause styles of deadlifting. Twenty physically active males performed deadlifts at their 75% one-repetition maximum testing using both pause and bounce techniques in a within-subjects randomized study design. The average peak height the barbell attained from the 3 bounce style repetitions was used to compute a compatible phase for analysis of the pause style repetitions. Net joint moment impulse (NJMI), work, average vertical ground reaction force (vGRF), vGRF impulse, and phase time were computed for 2 phases, liftoff to peak barbell height and the entire ascent. Additionally, the ankle, knee, hip, and trunk angles at the location of peak barbell bounce height were computed. During the liftoff to peak barbell height phase, although each of the joints demonstrated significantly less NJMI and work during the bounce style, the hip joint was impacted the most. The average vGRF was greater for the bounce; however, the vGRF impulse was greater for the pause. The NJMI results for the ascent phase were similar to the liftoff to peak barbell height phase, whereas work was significantly less for the bounce condition compared with the pause condition across all 3 joints. Strength and conditioning specialists using the deadlift should be aware that the bounce technique does not allow the athlete to develop maximal force production in the early portion of the lift. Further analyses should focus on joint angles and potential vulnerability to injury when the barbell momentum generated from the bounce is lost.
Improved Performance in Master Runners Competing in the European Championships Between 1978 and 2014
Authors: Schneider Anaïs L. , Nikolaidis Pantelis T. , Knechtle Beat 
Published: February 2018

Abstract
Schneider, AL, Nikolaidis, PT, and Knechtle, B. Improved performance in master runners competing in the European championships between 1978 and 2014. J Strength Cond Res 33(9): 2559–2569, 2019—The performance trends in elite runners have been well investigated, but we have no knowledge about performance trends and the difference between the sexes in elderly runners competing at a high level in varying distances. The purpose of this study was to investigate the performance of these age groups. Data from 17 European Championships held between 1978 and 2014 were analyzed for various race distances (i.e., 100, 200, 400, 800, 1,500, 5,000, 10,000 m, and marathon). Running speed for the top 8 female and male finalists for each age group (35–99 years, split into 5-year gaps) and each race distance were included. A 2-way analysis of variance compared the effects of sex, race distance, age group and calendar year on speed. Subsequent comparisons between race distances, age groups, or calendar years were performed using a post hoc Bonferroni’s test. Our analysis shows that men were faster than women in all distances, and the difference between the sexes was greater in the shorter distances. Speed was higher for shorter distances than for longer distances. Younger participants were faster than older ones, and the effect of age group was the largest for the 200 m. There was a minor effect of calendar year on speed in the 100, 20, 1,500, 10,000 m and marathon, and a minor calendar year × sex interaction on running speed was shown for the 200 m. For athletes and coaches, the current study demonstrates that both male and female athletes improved their running performance over time and that the sex gap may have reached its limit.
Using a Load-Velocity Relationship to Predict One repetition maximum in Free-Weight Exercise: A Comparison of the Different Methods
Authors: Hughes Liam J. , Banyard Harry G. , Dempsey Alasdair R. , Scott Brendan R. 
Published: February 2018

Abstract
Hughes, LJ, Banyard, HG, Dempsey, AR, and Scott, BR. Using a load-velocity relationship to predict one repetition maximum in free-weight exercise: a comparison of the different methods. J Strength Cond Res 33(9): 2409–2419, 2019—The purpose of this study was to investigate the reliability and validity of predicting 1 repetition maximum (1RM) in trained individuals using a load-velocity relationship. Twenty strength-trained men (age: 24.3 ± 2.9 years, height: 180.1 ± 5.9 cm, and body mass: 84.2 ± 10.5 kg) were recruited and visited the laboratory on 3 occasions. The load-velocity relationship was developed using the mean concentric velocity of repetitions performed at loads between 20 and 90% 1RM. Predicted 1RM was calculated using 3 different methods discussed in existing research: minimal velocity threshold 1RM (1RMMVT), load at zero velocity 1RM (1RMLD0), and force-velocity 1RM methods (1RMFV). The reliability of 1RM predictions was examined using intraclass correlation coefficient (ICC) and coefficient of variation (CV). 1RMMVT demonstrated the highest reliability (ICC = 0.92–0.96, CV = 3.6–5.0%), followed by 1RMLD0 (ICC = 0.78–0.82, CV = 8.2–8.6%) and 1RMFV (ICC = −0.28 to 0.00, CV = N/A). Both 1RMMVT and 1RMLD0 were very strongly correlated with measured 1RM (r = 0.91–0.95). The only method which was not significantly different to measured 1RM was the 1RMLD0 method. However, when analyzed on an individual basis (using Bland-Altman plots), all methods exhibited a high degree of variability. Overall, the results suggest that the 1RMMVT and 1RMLD0 predicted 1RM values could be used to monitor strength progress in trained individuals without the need for maximal testing. However, given the significant differences between 1RMMVT and measured 1RM, and the high variability associated with individual predictions performed using each method, they cannot be used interchangeably; therefore, it is recommended that predicted 1RM is not used to prescribe training loads as has been previously suggested.
Frequency Speed of Kick Test Performance Comparison Between Female Taekwondo Athletes of Different Competitive Levels
Authors: Santos Jonatas Ferreira da Silva , Franchini Emerson 
Published: February 2018

Abstract
Santos, JFS and Franchini, E. Frequency speed of kick test performance comparison between female taekwondo athletes of different competitive levels. J Strength Cond Res 32(10): 2934–2938, 2018—Construct validity is a desirable characteristic in any performance test to differentiate athletes. However, no taekwondo-specific test was investigated with this purpose. The purpose of this study was to compare female taekwondo athletes grouped in different competitive levels. Forty-two female taekwondo athletes divided into International/National (median [interquartile range]; n = 21, age: 20 [18–25] years; body mass: 60 [53–72] kg; height: 164 [161–170] cm; and practice time: 8 [5–13] years) and State/Regional group (median [interquartile range]; n = 21; age: 18 [17–25] years; body mass: 57 [52–63] kg; height: 165 [160–172] cm; and practice time: 5 [2–8] years) volunteered to participate in this study. The female taekwondo athletes performed frequency speed of kick test (FSKT) with 10 seconds (FSKT10s) and intermittent 90 seconds (FSKTmult) during the competitive period. Differences between international/national and state/regional group were observed, with superiority to international/national group, for FSKT10s (U = 114.5, p = 0.007, ESr (effect size) = −0.42 [small]), FSKT1 (U = 127.0, p = 0.016, ESr = −0.37 [small]), FSKT2 (U = 108.5, p = 0.004, ESr = −0.45 [small]), FSKT3 (U = 127.0, p = 0.015, ESr = −0.37 [small]), and FSKTtotal (U = 124.0, p = 0.015, ESr = −0.38 [small]). Based on the results of this study, the FSKT seems to be a good tool to discriminate performance of female taekwondo athletes and could be used by coaches and athletes in their evaluation routines.
Effect of Barbell Load on Vertical Jump Landing Force-Time Characteristics
Authors: Lake Jason P. , Mundy Peter D. , Comfort Paul , McMahon John J. , Suchomel Timothy J. , Carden Patrick 
Published: February 2018

Abstract
Lake, JP, Mundy, PD, Comfort, P, McMahon, JJ, Suchomel, TJ, and Carden, P. Effect of barbell load on vertical jump landing force-time characteristics. J Strength Cond Res 35(1): 25–32, 2021—The aim of this study was to quantify the effect that barbell load has on the jump height and force-time characteristics of the countermovement jump (CMJ). Fifteen strength-trained men (mean ± SD: age 23 ± 2 years, mass 84.9 ± 8.1 kg, and height 1.80 ± 0.05 m) performed 3 CMJs with no additional load, and with barbell loads of 25, 50, 75, and 100% of body mass on 2 force plates recording at 1,000 Hz. Propulsion and landing force-time characteristics were obtained from force-time data and compared using analysis of variance and effect sizes. Jump height decreased significantly as load increased (26–71%, d = 1.80–6.87). During propulsion, impulse increased with load up to 75% of body mass (6–9%, d = 0.71–1.08), mean net force decreased (10–43%, d = 0.50–2.45), and time increased (13–50%, d = 0.70–2.57). During landing, impulse increased as load increased up to 75% of body mass (5 to 12%, d = 0.54–1.01), mean net force decreased (13–38%, d = 0.41–1.24), and time increased (20–47%, d = 0.65–1.47). Adding barbell load to CMJ significantly decreases CMJ height. Furthermore, CMJ with additional barbell load increases landing phase impulse. However, while mean net force decreases as barbell load increases, landing time increases so that jumpers are exposed to mechanical load for longer. Practitioners should exercise caution when implementing loaded CMJ to assess their athletes.
The Match Heart Rate and Running Profile of Elite Under-21 Hurlers During Competitive Match-Play
Authors: Young Damien , Mourot Laurent , Beato Marco , Coratella Giuseppe 
Published: February 2018

Abstract
Young, D, Mourot, L, Beato, M, and Coratella, G. The match heart rate and running profile of elite under-21 hurlers during competitive match-play. J Strength Cond Res 32(10): 2925–2933, 2018—The aims of the current study were to examine the physical and physiological demands of elite under-21 male hurling match-play across halves of play and between positions. Global positioning systems (10 Hz) and heart rate (HR) monitors were used to collect data from 95 players during 10 games. Total distance (TD), relative speed, high-speed running (HSR), sprint distance, total sprints, and mean length of sprint was 6,688 ± 942 m, 112 ± 16 m·min−1, 661 ± 203 m, 274 ± 111 m, 18 ± 8 m, and 16 ± 5 m, respectively. Players' mean HR (HRmean) and peak HR (HRpeak) was 165 ± 9 b·min−1 and 190 ± 7 b·min−1, respectively. Decrements in TD (p < 0.05, effect size [ES] = 0.81), HSR (p < 0.05, ES = 0.69), and HRmean (p < 0.05, ES = 0.80) were found between halves. Full backs covered significantly less TD than half backs (p < 0.05, ES = −1.24), midfielders (p < 0.05, ES = −1.39), and half forwards (p < 0.05, ES = −1.85). Half forwards covered a greater TD than full forwards (p < 0.05, ES = 0.94), greater HSR than full backs (p < 0.05, ES = 1.13), and greater sprint distance than half backs (p < 0.05, ES = 1.41). Between-half decreases were evident in TD, HSR, and HRmean, with no significant positional differences observed in TD, HSR, number of sprints, length of sprint, HRpeak, and HRmean between half backs, midfielders, and half forwards. The current findings provide data that coaches should consider to customize training program design for under-21 hurlers.
A Genomic Reference Panel for Drosophila serrata
Authors: Reddiex Adam J , Allen Scott L , Chenoweth Stephen F 
Published: February 2018

Abstract
Here we describe a collection of re-sequenced inbred lines of Drosophila serrata, sampled from a natural population situated deep within the species endemic distribution in Brisbane, Australia. D. serrata is a member of the speciose montium group whose members inhabit much of south east Asia and has been well studied for aspects of climatic adaptation, sexual selection, sexual dimorphism, and mate recognition. We sequenced 110 lines that were inbred via 17-20 generations of full-sib mating at an average coverage of 23.5x with paired-end Illumina reads. 15,228,692 biallelic SNPs passed quality control after being called using the Joint Genotyper for Inbred Lines (JGIL). Inbreeding was highly effective and the average levels of residual heterozygosity (0.86%) were well below theoretical expectations. As expected, linkage disequilibrium decayed rapidly, with r2 dropping below 0.1 within 100 base pairs. With the exception of four closely related pairs of lines which may have been due to technical errors, there was no statistical support for population substructure. Consistent with other endemic populations of other Drosophila species, preliminary population genetic analyses revealed high nucleotide diversity and, on average, negative Tajima’s D values. A preliminary GWAS was performed on a cuticular hydrocarbon trait, 2-Me-C28 revealing 4 SNPs passing Bonferroni significance residing in or near genes. One gene Cht9 may be involved in the transport of CHCs from the site of production (oenocytes) to the cuticle. Our panel will facilitate broader population genomic and quantitative genetic studies of this species and serve as an important complement to existing D. melanogaster panels that can be used to test for the conservation of genetic architectures across the Drosophila genus.
A Metagenome-Wide Association Study and Arrayed Mutant Library Confirm Acetobacter Lipopolysaccharide Genes Are Necessary for Association with Drosophila melanogaster
Authors: White K Makay , Matthews Melinda K , Hughes Rachel C , Sommer Andrew J , Griffitts Joel S , Newell Peter D , Chaston John M 
Published: February 2018

Abstract
A metagenome wide association (MGWA) study of bacterial host association determinants in Drosophila predicted that LPS biosynthesis genes are significantly associated with host colonization. We were unable to create site-directed mutants for each of the predicted genes in Acetobacter, so we created an arrayed transposon insertion library using Acetobacter fabarum DsW_054 isolated from Drosophila. Creation of the A. fabarum DsW_054 gene knock-out library was performed by combinatorial mapping and Illumina sequencing of random transposon insertion mutants. Transposon insertion locations for 6,418 mutants were successfully mapped, including hits within 63% of annotated genes in the A. fabarum DsW_054 genome. For 45/45 members of the library, insertion sites were verified by arbitrary PCR and Sanger sequencing. Mutants with insertions in four different LPS biosynthesis genes were selected from the library to validate the MGWA predictions. Insertion mutations in two genes biosynthetically upstream of Lipid-A formation, lpxC and lpxB, show significant differences in host association, whereas mutations in two genes encoding LPS biosynthesis functions downstream of Lipid-A biosynthesis had no effect. These results suggest an impact of bacterial cell surface molecules on the bacterial capacity for host association. Also, the transposon insertion mutant library will be a useful resource for ongoing research on the genetic basis for Acetobacter traits.
Geomorfologia estrutural, morfotectônica e morfometria da folha Cartagena 1:100.000–Colômbia
Authors: Furrier Max , Vargas Cuervo Germán 
Published: February 2018

Este trabajo presenta una nueva caracterización geomorfológica de la región de Cartagena de Indias (Plancha 23 igac), se ha elaborado una cartografía morfoestructural, morfométrica y tectónica. Desde el punto de vista geomorfológico, el relieve está dominado por la presencia de dos cinturones rocosos estructurales: la Serranía de San Jacinto y la Serranía del Sinú. El primer cinturón, se localiza en el sector oriental de la zona y se compone principalmente de rocas sedimentarias de la Formación San Cayetano del Paleoceno, que desarrollan cimas de filos de gran altura. El Cinturón de la Serranía del Sinú, se presenta al oeste del Cinturón de San Jacinto, separado por la falla Villa Nueva - El Totumo. Allí se presenta la formación geológica más antigua del área de edad Oligoceno-Mioceno. Los sectores de menor relieve corresponden a las planicies y formas suavemente inclinadas y onduladas compuestas por depósitos no consolidados de tipo aluvial y coluvial de edad cuaternario. A partir de la interpretación de imágenes de satélite de tipo óptico y de radar y el uso de modelos digitales de terreno, en conjunto con las observaciones de campo, análisis de perfiles topográficos y la cartografía geomorfológica, se puede concluir que la tectónica cenozoica es el factor más importante en la configuración del relieve en la zona, que se evidencia por la configuración morfométrica de la red de drenaje.
Resiliencia comunitaria frente a los desastres naturales: caleta Tumbes, región del Biobío, Chile
Authors: Flores Cisternas Paulina Tiare , Sanhueza Contreras Rodrigo Alejandro 
Published: February 2018

Se analizó la resiliencia comunitaria de caleta Tumbes frente a un desastre natural y su Plan de Reconstrucción, según cinco dimensiones. Para ello, se aplicaron encuestas a la población. Los resultados indicaron que las dimensiones más sólidas de resiliencia son la identidad cultural asociada a la actividad pesquera; la autoestima colectiva, donde destacan aspectos de topofilia; y el humor social asociado a la manera colectiva de enfrentar situaciones adversas. Las dimensiones más débiles fueron la honestidad gubernamental comunitaria y la estructura social cohesionada. Respecto del Plan de Reconstrucción, los proyectos finalizados fueron evaluados favorablemente, aun cuando no contribuyeron a mejorar la resiliencia, dada la baja participación de la comunidad en su elaboración, lo que generó nuevos conflictos sociales.
Effect of endocrine disruptor phytoestrogens on the immune system: Present and future
Authors: Csaba György 
Published: February 2018

Endocrine disruptors (EDs) are bound by steroid receptors, have steroid-like effects, and by this, negatively influence hormone-regulated processes. Phytoestrogens, which are consumed in enormously high amount by man, are also EDs; however, in contrast to industrial or communal EDs, in some cases have beneficial effects. As immune cells have steroid (first of all, estrogen) nuclear and plasma membrane receptors, which bind phytostrogens (genistein, daidzein, etc.), the development, lifespan, and function of them are deeply influenced by phytoestrogens. They can provoke perinatal faulty hormonal imprinting with lifelong consequences. However, faulty imprinting can be developed not only perinatally but also in other critical periods of life, as weaning, adolescence, and even in continuously dividing cells (e.g., hemopoietic cells) during the whole life. This means that the phytoestrogens could cause direct – instant or long-lasting – steroid effects and durable imprinting effects. As the effect of hormonal imprinting is epigenetically inherited, the phytoestrogen’s effects appear in the progeny generations, and the generationally repeated disruptor effects will be different from the present ones. This could also be manifested in the amount, type, and appearance of autoimmune diseases. The consumption of soy is enormously growing, and its immune effect is extended. As the immune system influences basic physiological processes, it seems likely that evolutionary alterations will be observed. In this case, some phytoestrogens will be needed for the normal life of man, as it happened in the case of vitamins A and D, which are already life-important exohormones. However, quantitatively or qualitatively enormous amount of phytoestrogens will cause pathological and epigenetically inherited alterations.
Internet gaming disorder in Lebanon: Relationships with age, sleep habits, and academic achievement
Authors: Hawi Nazir S. , Samaha Maya , Griffiths Mark D. 
Published: February 2018

Background and aims
The latest (fifth) edition of the Diagnostic and Statistical Manual of Mental Disorders included Internet gaming disorder (IGD) as a disorder that needs further research among different general populations. In line with this recommendation, the primary objective of this was to explore the relationships between IGD, sleep habits, and academic achievement in Lebanese adolescents.

Methods
Lebanese high-school students (N = 524, 47.9% males) participated in a paper survey that included the Internet Gaming Disorder Test and demographic information. The sample’s mean average age was 16.2 years (SD = 1.0).

Results
The pooled prevalence of IGD was 9.2% in the sample. A hierarchical multiple regression analysis demonstrated that IGD was associated with being younger, lesser sleep, and lower academic achievement. While more casual online gamers also played offline, all the gamers with IGD reported playing online only. Those with IGD slept significantly less hours per night (5 hr) compared with casual online gamers (7 hr). The school grade average of gamers with IGD was the lowest among all groups of gamers, and below the passing school grade average.

Conclusions
These findings shed light on sleep disturbances and poor academic achievement in relation to Lebanese adolescents identified with IGD. Students who are not performing well at schools should be monitored for their IGD when assessing the different factors behind their low academic performance.
Efeito da prática do suporte de peso corporal na função motora de crianças
Authors: Reitz Geison Sebastião , De Oliveira Deise Ferreira , De Souza Crippa Patrícia Vieira , Roesler Helio 
Published: February 2018

OBJETIVO. Avaliar a influência do Suporte de Peso Corporal (SPC) sobre a função motora de crianças não deambulantes. MÉTODOS. Participaram do estudo oito crianças que não apresentavam o padrão de marcha. Foi realizada a identificação do desempenho da função motora grossa por meio da Gross Motor Function Classification Measure (GMFM) e da flexibilidade por meio do Teste Flexiteste, antes e após 10 sessões e um período de retenção durante 3 meses de tratamento com SPC em esteira ergométrica. Tendo assistência de dois terapeutas que auxiliavam em pontos chaves de joelho e tornozelo simulando o padrão de marcha da criança. As sessões foram realizadas uma vez por semana, durante 30 minutos, por um período de 3 meses e o mesmo de retenção. RESULTADOS. O GMFM apresentou aumento das pontuações obtidas pré/pós-tratamento e retenção nos itens deitar/rolar e sentar, já o item engatinhar/ajoelhar mostrou diferença significativa apenas no período pré/pós-tratamento. A variável flexibilidade apresentou diferença significativa entre o pré e pós-tratamento e no pós-tratamento com o período de retenção. CONCLUSÃO. O tratamento com SPC em esteira ergométrica pode potencializar o desempenho funcional de crianças não-deambulantes, possibilitando a evolução de sua função motora grossa e flexibilidade.