Physiological Responses to Facemask Use during a Graded Treadmill Test in Healthy Male Adolescents and Young.

Background: we aimed to investigate the physiological impact of facemasks use during a graded treadmill exercise test in male adolescents and young adults.

Materials And Methods: Twenty-one males aged 15 to 28 volunteered. Participants completed four sessions with a 72-hour gap between each session.

High-density stable glasses formed on soft substrates.

Enabled by surface-mediated equilibration, physical vapour deposition can create high-density stable glasses comparable with liquid-quenched glasses aged for millions of years. Deposition is often performed at various rates and temperatures on rigid substrates to control the glass properties. Here we demonstrate that on soft, rubbery substrates, surface-mediated equilibration is enhanced up to 170 nm away from the interface, forming stable glasses with densities up to 2.

Water balance affects foliar and soil nutrients differently.

Water balance influences soil development, and consequently plant communities, by driving weathering of soil minerals and leaching of plant nutrients from the soil. Along gradients in water balance, soils exhibit process domains where chemical properties are relatively stable punctuated by pedogenic thresholds where soil chemical properties change rapidly with little additional change in water balance. We ask if plant macronutrient concentrations in leaves also exhibit non-linear trends along water balance gradients, and if so, how these non-linearities relate to those in soils.

Hemodynamic response and pulse wave analysis after upper- and lower-body resistance exercise with and without blood flow restriction.

Resistance exercise (RE) has been shown to elevate hemodynamics and pulse wave reflection. However, the effects of acute RE with blood flow restriction (BFR) on hemodynamics and pulse wave reflection are unclear. The purpose of this study was to evaluate the differences between upper- and lower-body RE with and without BFR on hemodynamics and pulse wave reflection.

Predictors of placental malaria in Upper West Regional Hospital-Ghana.

Background: Placental malaria (PM) poses life-threatening complications to pregnant women as they are at increased risk of maternal and perinatal morbidity and mortality associated with malaria. This study examined the factors associated with placental malaria in the Upper West Regional Hospital (UWR).

Methods: A cross-sectional hospital-based study was carried out among pregnant women delivering at Upper West Regional Hospital.

Energy drink expectancies among college students.

Since the late '90 s, energy drink consumption has increased. The purpose of this investigation was to examine energy drink expectancies of college students. The university registrar randomly selected fifty university classes to be surveyed.

Validity and reliability evidence for motor competence assessments in children and adolescents: A systematic review.

Valid and reliable tests of motor competence are necessary to allow researchers and practitioners to quantify levels of motor competence, identify skill deficiencies, and determine the effectiveness of motor skill interventions. The primary study aim was to systematically review the validity and reliability of scores derived from gross motor competence tests for typically developing child and adolescent populations. The secondary aim of this review was to identify the most prevalent motor skills assessed across all instruments.

Highlighting Contributions of Behavioral and Social Sciences in Advancing Public Health: Where We've Come, Where We're Headed.

Context: Social and behavioral sciences, a cross-disciplinary field that examines the interaction among behavioral, biological, environmental, and social factors, has contributed immensely to some public health achievements over the last century. Through collaboration with community organizations and partners, social and behavioral scientists have conducted numerous program interventions involving community engagement and advocacy efforts at the local, state, federal, and international levels.

Contributions Of Social And Behavioral Sciences: This article traces select historical underpinnings of the applications of social and behavioral sciences theories and evidence to public health and highlights 4 areas in which health education specialists have distinctly contributed to public health achievements by building on theory and evidence.

Setting boundaries: Utilization of time to boundary for objective evaluation of the balance error scoring system.

Subjective evaluations of balance performance, like the modified Balance Error Scoring System (mBESS), are highly popular. Alternatively, quantitative measures may offer additional clarity in identifying balance dysfunction. A novel measure to define balance impairments is time to boundary (TTB), which represents the amount of time available to make corrective postural adjustments prior to the centre of pressure (CoP) reaching the edge of the base of support.

Menaquinone Biosynthesis: Biochemical and Structural Studies of Chorismate Dehydratase.

Menaquinone (MK, vitamin K) is a lipid-soluble quinone that participates in the bacterial electron transport chain. In mammalian cells, vitamin K functions as an essential vitamin for the activation of several proteins involved in blood clotting and bone metabolism. MqnA is the first enzyme on the futalosine-dependent pathway to menaquinone and catalyzes the aromatization of chorismate by water loss.

Leveling the playing field: Evaluation of a portable instrument for quantifying balance performance.

Balance is a complex, sensorimotor task requiring an individual to maintain the center of gravity within the base of support. Quantifying balance in a reliable and valid manner is essential to evaluating disease progression, aging complications, and injuries in clinical and research settings. Typically, researchers use force plates to track motion of the center of gravity during a variety of tasks.

Guideposts and Roadblocks to the Career-Long Scholarly Engagement of Physical Education Teacher Education Faculty.

Purpose: Scholarship is essential for the growth and development of the physical education field. Over time, scholarship expectations have changed, forcing faculty members to alter time spent for research, teaching, and service. Social-cognitive career theory (SCCT) presents a model for understanding performance and persistence in an occupational environment.

Physiology in Medicine: Understanding dynamic alveolar physiology to minimize ventilator-induced lung injury.

Acute respiratory distress syndrome (ARDS) remains a serious clinical problem with the main treatment being supportive in the form of mechanical ventilation. However, mechanical ventilation can be a double-edged sword: if set improperly, it can exacerbate the tissue damage caused by ARDS; this is known as ventilator-induced lung injury (VILI). To minimize VILI, we must understand the pathophysiologic mechanisms of tissue damage at the alveolar level.

Averaging Trials Versus Averaging Trial Peaks: Impact on Study Outcomes.

Gait data are commonly presented as an average of many trials or as an average across participants. Discrete data points (eg, maxima or minima) are identified and used as dependent variables in subsequent statistical analyses. However, the approach used for obtaining average data from multiple trials is inconsistent and unclear in the biomechanics literature.

Is there more than one way to skin a newt? Convergent toxin resistance in snakes is not due to a common genetic mechanism.

Convergent evolution of tetrodotoxin (TTX) resistance, at both the phenotypic and genetic levels, characterizes coevolutionary arms races between amphibians and their snake predators around the world, and reveals remarkable predictability in the process of adaptation. Here we examine the repeatability of the evolution of TTX resistance in an undescribed predator-prey relationship between TTX-bearing Eastern Newts (Notophthalmus viridescens) and Eastern Hog-nosed Snakes (Heterodon platirhinos). We found that that local newts contain levels of TTX dangerous enough to dissuade most predators, and that Eastern Hog-nosed Snakes within newt range are highly resistant to TTX.

The deconvolution of differential scanning calorimetry unfolding transitions.

This paper is a review of a process for deconvolution of unfolding thermal transitions measured by differential scanning calorimetry. The mathematical background is presented along with illustrations of how the unfolding data is processed to resolve the number of sequential transitions needed to describe an unfolding mechanism and to determine thermodynamic properties of the intermediate states. Examples of data obtained for a simple two-state unfolding of a G-quadruplex DNA structure derived from the basic human telomere sequence, (TTAGGG)4TT are used to present some of the basic issues in treating the DSC data.

Mechanical breath profile of airway pressure release ventilation: the effect on alveolar recruitment and microstrain in acute lung injury.

Importance: Improper mechanical ventilation settings can exacerbate acute lung injury by causing a secondary ventilator-induced lung injury. It is therefore important to establish the mechanism by which the ventilator induces lung injury to develop protective ventilation strategies. It has been postulated that the mechanism of ventilator-induced lung injury is the result of heterogeneous, elevated strain on the pulmonary parenchyma.

Thermodynamics of forming a parallel DNA crossover.

The process of genetic recombination involves the formation of branched four-stranded DNA structures known as Holliday junctions. The Holliday junction is known to have an antiparallel orientation of its helices, i.e.

The relationships among fundamental motor skills, health-related physical fitness, and body fatness in South Korean adolescents with mental retardation.

The purpose of this study was to examine the following: (a) the relationships among the latent constructs of fundamental motor skills (FMS), health-related physical fitness (HRF), and observed body fatness in South Korean adolescents with mental retardation (MR); (b) the indirect effect of fundamental motor skills on body fatness when mediated by health-related fitness; and (c) whether the degree of MR and gender affects these relationships. Students ages 13 to 18 years (287 boys and 134 girls) were recruited for the study. Separate structural equation models were estimated based on gender and the level of disability: mild or moderate MR.

Differential scanning calorimetry.

Differential scanning calorimetry (DSC) has emerged as a powerful experimental technique for determining thermodynamic properties of biomacromolecules. The ability to monitor unfolding or phase transitions in proteins, polynucleotides, and lipid assemblies has not only provided data on thermodynamic stability for these important molecules, but also made it possible to examine the details of unfolding processes and to analyze the characteristics of intermediate states involved in the melting of biopolymers. The recent improvements in DSC instrumentation and software have generated new opportunities for the study of the effects of structure and changes in environment on the behavior of proteins, nucleic acids, and lipids.

Enthalpies of DNA melting in the presence of osmolytes.

The melting of DNA in the presence of osmolytes has been studied with the intention of obtaining information about how base pair stability is affected by changes in solution conditions. In previous investigations, the melting enthalpies were assumed to be constant as osmolalities change, but no systematic evaluation of whether this condition is true has been offered. This paper presents calorimetric data on the melting of two synthetic DNA samples in the presence of a number of common osmolytes.

Life-cycle aspects of poverty among older women.

This article focuses on the relationship between women's economic status earlier in their lives and their poverty status in old age. Previous research on the determinants of poverty among aged women has documented the socioeconomic and demographic correlates of the poor, and has examined the financial impact of adverse later-life events such as widowhood, deterioration of health, and loss of employment. Using data from the National Longitudinal Survey of Mature Women (NLSMW), we find that most women who experience these types of adverse events in their later years do not become poor and that a large majority of older NLSMW respondents who were poor in 1991-92 were poor earlier in their adult lives.

Thermodynamics of transfer of cholesterol from gel to fluid phases of phospholipid bilayers.

The partitioning of cholesterol between gel and fluid phases of model membrane bilayers has been studied by differential scanning calorimetry. The partition coefficients and thermodynamics of transfer between phases of dimyristoyl-, dipalmitoyl-, distearoyl- and diarachidoylphosphatidylcholines were determined using a regular solution model for the partitioning process. The partition coefficient, which is the ratio of cholesterol in fluid to gel phase lipid, varies from 2.