Flexible automated system for laser modified layer by layer assembly.

An open-source automated system for laser modified layer by layer assembly is described. This flexible system, the first designed to be used with this process, can be used to fabricate a range of laser patterned, layer by layer thin films. The Arduino microcontroller-based system features a stepper motor-controlled turntable that holds solutions and water rinses for dipping.

The impact of COVID-19 pandemic on the dynamic correlations between gold and U.S. equities: evidence from multifractal cross-correlation analysis.

This study exploits multifractal cross-correlation analysis (MFCCA) to investigate the impact of the COVID-19 pandemic on the cross-correlations between gold and U.S. equity markets using 1-min high-frequency data from January 1, 2019, to December 29, 2020.

Three-dimensional control of layer by layer thin films via laser modification.

A novel modification to the traditional layer by layer process that adds three-dimensional control to the technique is introduced. In this modification to the process, the substrate is irradiated with laser light during the polycation and/or polyanion dipping cycles. An array of PAH/PCBS polymer thin films were fabricated using the laser modified approach with varied bilayer numbers, laser powers, and laser irradiation times.

Can news-based economic sentiment predict bubbles in precious metal markets?

This study examines the role of market sentiment in predicting the price bubbles of four strategic metal commodities (gold, silver, palladium, and platinum) from January 1985 to August 2020. It is the first to investigate this topic using sentiment indices, including news-based economic and consumer-based sentiments developed using different methods. We observed the role of sentiment as a reliable indicator of future bubbles for some metal commodities and found that bubbles were regularly concomitant with bearish sentiments for gold and platinum.

COVID-19 and the volatility interlinkage between bitcoin and financial assets.

We investigate the effects of COVID-19 on volatility connectedness between bitcoin and five traditional financial assets from the gold, oil, foreign exchange, stock, and bond markets, employing high-frequency data. The empirical analyses are carried out using the wavelet coherence approach and dynamic frequency-domain connectedness method. Our results generally indicate that the volatility dynamics between bitcoin and the financial assets are weak or negative before the pandemic while they become positive during the pandemic times for most of the assets.

Comprehensive Physical Activity Assessment During U.S. Army Basic Combat Training.

Alemany, JA, Pierce, JR, Bornstein, DB, Grier, TL, Jones, BH, and Glover, SH. Comprehensive physical activity assessment during U.S.

Training for Muscular Strength: Methods for Monitoring and Adjusting Training Intensity.

Linear loading, the two-for-two rule, percent of one repetition maximum (1RM), RM zones, rate of perceived exertion (RPE), repetitions in reserve, set-repetition best, autoregulatory progressive resistance exercise (APRE), and velocity-based training (VBT) are all methods of adjusting resistance training intensity. Each method has advantages and disadvantages that strength and conditioning practitioners should be aware of when measuring and monitoring strength characteristics. The linear loading and 2-for-2 methods may be beneficial for novice athletes; however, they may be limited in their capacity to provide athletes with variation and detrimental if used exclusively for long periods of time.

Dynamic Strength Index: Relationships with Common Performance Variables and Contextualization of Training Recommendations.

The purposes of this study were to examine the relationships between dynamic strength index (DSI) and other strength-power performance characteristics and to contextualize DSI scores using case study comparisons. 88 male and 67 female NCAA division I collegiate athletes performed countermovement jumps (CMJ) and isometric mid-thigh pulls (IMTP) during a pre-season testing session as part of a long-term athlete monitoring program. Spearman's correlations were used to assess the relationships between DSI and CMJ peak force, height, modified reactive strength index, peak power and IMTP peak force and rate of force development (RFD).

Offspring Self-Disclosure Predicts Substance-Related Outcomes in an Emergency Department Sample of Young Adults with Traumatic Injury.

Background: Hundreds of thousands of individuals visit the emergency department (ED) every year, with many visits occurring following alcohol misuse. Parent-child relationship factors are associated with alcohol-related outcomes. For example, offspring choice to self-disclose information about their lives to parents, rather than parents actively soliciting this information, is associated with substance use.

The effect of digital media on children in their formative years.

Over the past 2 decades, personal digital devices have evolved to become portable, attractive, readily accessible, interactive, and ubiquitous. Although digital and social media have evidence-based benefits, including early learning, exposure to new ideas and knowledge, and increased opportunities for social contact and support, unsupervised and unchecked use of personal digital devices can have negative consequences for the physical and mental health of children in their formative years.The widespread use of portable digital devices has been accompanied by a concomitant rise in the prevalence of physical and mental health issues in children.

The density bias: Capuchin monkeys (Sapajus apella) prefer densely arranged items in a food-choice task.

In the current work, we investigated whether capuchin monkeys preferred densely distributed resources to sparsely distributed resources in a 2-choice discrimination task with edible rewards. Capuchin monkeys were biased to select a denser food set over the same number of food items in a sparsely arranged set. Furthermore, increased density of the larger food set facilitated discrimination performance in quantity comparisons with a true difference in set size.

Intrasession and Intersession Reliability of Countermovement Jump Testing in Division-I Volleyball Athletes.

Carroll, KM, Wagle, JP, Sole, CJ, and Stone, MH. Intrasession and intersession reliability of countermovement jump testing in Division-I volleyball athletes. J Strength Cond Res 33(11): 2932-2935, 2019-The countermovement jump (CMJ) is a reliable and noninvasive test of lower-body neuromuscular performance.

Recommendations for Measurement and Management of an Elite Athlete.

Athletes who merit the title 'elite' are rare and differ both quantitatively and qualitatively from athletes of lower qualifications. Serving and studying elite athletes may demand non-traditional approaches. Research involving elite athletes suffers because of the typical nomothetic requirements for large sample sizes and other statistical assumptions that do not apply to this population.

A Multi-Campus Pilot Feasibility Evaluation of a Bystander-Based Sexual Violence Prevention Program: Exploring the Influence of Drinking Behaviors on Bystander Behavior.

Researchers and policy makers are devoting considerable attention to the development and evaluation of sexual violence prevention programming for college campuses. Although several programs have been developed over the last decade, questions remain about whether programs can be effectively implemented across diverse campuses and whether individual-level factors like alcohol use moderate program effectiveness. The purpose of this pilot study was to evaluate the impact of a brief, sexual violence prevention program-The Men's Program-on two diverse campuses.

Preliminary Scale of Reference Values for Evaluating Reactive Strength Index-Modified in Male and Female NCAA Division I Athletes.

The purpose of this analysis was to construct a preliminary scale of reference values for reactive strength index-modified (RSI). Countermovement jump data from 151 National Collegiate Athletic Association (NCAA) Division I collegiate athletes (male n = 76; female n = 75) were analyzed. Using percentiles, scales for both male and female samples were constructed.

Force-Time Differences between Ballistic and Non-Ballistic Half-Squats.

The purpose of this study was to examine the force-time differences between concentric-only half-squats (COHS) performed with ballistic (BAL) or non-ballistic (NBAL) intent across a range of loads. Eighteen resistance-trained men performed either BAL or NBAL COHS at 30%, 50%, 70%, and 90% of their one repetition maximum (1RM) COHS. Relative peak force (PF) and relative impulse from 0⁻50 ms (Imp50), 0⁻90 ms (Imp90), 0⁻200 ms (Imp200), and 0⁻250 ms (Imp250) were compared using a series of 2 × 4 (intent × load) repeated measures ANOVAs with Bonferroni post hoc tests.

Injuries in Collegiate Women's Volleyball: A Four-Year Retrospective Analysis.

A four-year retrospective analysis of injury data was conducted on a collegiate (NCAA Division I) women's volleyball team. Twenty athletes (Year 1: age = 19.4 ± 0.

Exploring the solitaire illusion in guppies (Poecilia reticulata).

The solitaire illusion is a numerosity illusion that occurs when the spatial arrangement of items influences quantity estimation. To date, this illusion has been reported in monkeys, although it seems to be weaker compared with its prevalence in humans, and no study has investigated whether nonprimate species perceive it. In the present work, we asked whether a more distantly related species, fish, perceived the solitaire illusion.

Power-Time Curve Comparison between Weightlifting Derivatives.

This study examined the power production differences between weightlifting derivatives through a comparison of power-time (P-t) curves. Thirteen resistance-trained males performed hang power clean (HPC), jump shrug (JS), and hang high pull (HHP) repetitions at relative loads of 30%, 45%, 65%, and 80% of their one repetition maximum (1RM) HPC. Relative peak power (PP), work (W), and P-t curves were compared.

Jumping Performance is Preserved but Not Muscle Thickness in Collegiate Volleyball Players After a Taper.

Bazyler, CD, Mizuguchi, S, Sole, CJ, Suchomel, TJ, Sato, K, Kavanaugh, AA, DeWeese, BH, and Stone, MH. Jumping performance is preserved but not muscle thickness in collegiate volleyball players after a taper. J Strength Cond Res 32(4): 1020-1028, 2018-The purpose of this study was to examine changes in muscle architecture and jumping performance in NCAA division I women's volleyball players throughout a competitive season and in preparation for conference championships.

PTSD symptoms predict outcome in trauma-informed treatment of intimate partner aggression.

Objective: This study sought to extend findings from a randomized controlled trial of the Strength at Home Men's Program (SAH-M) for intimate partner aggression (IPA) in military veterans by examining the impact of pretreatment posttraumatic stress disorder (PTSD) symptoms on treatment efficacy, and by examining new data on postintervention follow-up for individuals who received SAH-M after completing the enhanced treatment as usual (ETAU) wait-list control condition.

Method: Using data from 125 male veterans who attended the SAH-M program immediately after an intake assessment or after waiting 6-month in the ETAU condition, this study used generalized linear modeling to examine predictors of physical and psychological IPA over a 9-month period of time.

Results: PTSD symptoms at intake significantly predicted both physical and psychological IPA use, even after accounting for the effects of treatment condition, time, and number of sessions attended.

Phase Characteristics of the Countermovement Jump Force-Time Curve: A Comparison of Athletes by Jumping Ability.

Sole, CJ, Mizuguchi, S, Sato, K, Moir, GL, and Stone, MH. Phase characteristics of the countermovement jump force-time curve: a comparison of athletes by jumping ability. J Strength Cond Res 32(4): 1155-1165, 2018-The purpose of this study was to compare the phase characteristics of the countermovement jump (CMJ) force-time (F-t) curve between athletes based on jumping ability.