Control Condition Research Articles

Acute Effects of Cadence-Controlled Walking on Cognition and Vascular Function in Physically Inactive Older Adults: A Randomized Crossover Study.

Cadence-controlled walking may be a desirable approach for older adults to self-monitor exercise intensity and achieve physical activity guidelines. We examined the acute effects of cadence-controlled walking on cognition and vascular function in physically inactive older adults. In a randomized crossover design, 26 participants (65% females, 67.8 ± 11.3years) underwent 30-min acute exercise (walking at 100steps/min) and control (sitting) conditions. We measured cognition, central blood pressure (BP), and arterial stiffness before, and immediately, after each condition. We observed significant Time × Condition interactions in the Flanker Inhibitory Control and Attention (Flanker) test and Dimensional Change Card Sort (DCCS) test scores, and in central systolic BP, central pulse pressure, and carotid to femoral pulse wave velocity (p < .05). The Flanker and DCCS scores significantly increased after walking (d = 0.4 and 0.5, respectively), but not after sitting. Central systolic BP, central pulse pressure, and carotid to femoral pulse wave velocity significantly increased after sitting but remained unchanged after acute walking (d = 0.4-0.2), with p-values < .05. After walking, significant correlations were observed between DCCS and diastolic BP and central pulse pressure change scores and change scores in central pulse wave velocity,Flanker, and DCCS (rs = -0.45 to -0.52). These findings suggest that a single bout of cadence-controlled walking elicited an immediate improvement in cognition and might have mitigated increases in arterial stiffness and central BP observed in the seated control condition. Further research is needed to examine the association between cognition and vascular function following acute exercise compared to control conditions. Our findings may have practical implications for developing daily physical activity recommendations for improving the cognitive health for successful aging.

The blushing brain: neural substrates of cheek temperature increase in response to self-observation.

Darwin proposed that blushing-the reddening of the face owing to heightened self-awareness-is 'the most human of all expressions'. Yet, relatively little is known about the underlying mechanisms of blushing. Theories diverge on whether it is a rapid, spontaneous emotional response that does not involve reflection upon the self or whether it results from higher-order socio-cognitive processes. Investigating the neural substrates of blushing can shed light on the mental processes underlying blushing and the mechanisms involved in self-awareness. To reveal neural activity associated with blushing, 16-20 year-old participants (n = 40) watched pre-recorded videos of themselves (versus other people as a control condition) singing karaoke in a magnetic resonance imaging scanner. We measured participants' cheek temperature increase-an indicator of blushing-and their brain activity. The results showed that blushing is higher when watching oneself versus others sing. Those who blushed more while watching themselves sing had, on average, higher activation in the cerebellum (lobule V) and the left paracentral lobe and exhibited more time-locked processing of the videos in early visual cortices. These findings show that blushing is associated with the activation of brain areas involved in emotional arousal, suggesting that it may occur independently of higher-order socio-cognitive processes. Our results provide new avenues for future research on self-awareness in infants and non-human animals.

Mental health literacy in Australian schools: evaluation of the Australian adapted youth education and support program

ABSTRACT Objective The prevalence of youth mental illness is increasing, and accessible preventative approaches, such as school-based mental health literacy programs, are needed. Mental health literacy is the ability to understand how to obtain and maintain good mental health. Schools are an ideal and accessible setting to base programs targeting mental health literacy. Method This study used a non-randomised waitlist control design to evaluate the effects of the Youth Education and Support (YES) program on mental health literacy, help seeking, and resilience for 38 Australian youth (12 male, 26 female) aged 12–16 years (M = 14.05, SD = 1.01). Data was analysed using t-tests, frequency analyses, mixed-model repeated measures analysis of variance, and directed content analysis. Results No significant interaction effect on mental health literacy from pre to post intervention was found between participants in the YES condition and control condition. Participants (n = 26) were significantly more likely to seek help from a helpline for suicidal ideation than control (n = 12) postintervention. Participants within the YES condition demonstrated significantly improved mental health literacy from pre to postintervention. Conclusions This study provides initial evidence supporting the inclusion of mental health literacy programs in Australian school environments.

The time course of Temporal Binding in social and nonsocial interactions.

Temporal Binding (TB) is the subjective compression of action-effect intervals. While the effects of nonsocial actions are highly predictable, it is not the case when interacting with conspecifics, who often act under their own volition, at a time of their choosing. Given the relative differences in action-effect predictability in non-social and social interactions, it is plausible that TB and its properties differ across these situations. To examine this, in two experiments, we compared the time course of TB in social and nonsocial interactions, systematically varying action-effect intervals (200-2,100 ms). Participants were told they were (a) interacting with another person via a live webcam, who was in fact a confederate (social condition), (b) interacting with pre-recorded videos (nonsocial condition), or (c) observing two pre-recorded videos (control condition; Experiment 2). Results across experiments showed greater TB for social compared to nonsocial conditions, and the difference was proportional to the action-effect intervals. Further, in Experiment 1, TB was consistently observed throughout the experiment for social interactions, whereas nonsocial TB decreased from the first to the second half of the experiment. In Experiment 2, the nonsocial condition did not differ from control, whereas the social condition did, exhibiting enhanced binding. We argue these results suggest that the sociality of an interaction modulates the 'internal clock' of time perception.

Social anxiety and attentional bias to negative emotional information: the relationship and intervention

BackgroundAccording to the cognitive behavioral model of social anxiety, attentional bias to negative emotional information causes and maintains anxiety. The goal of attentional bias modification (ABM) is to reduce anxiety by reducing attention bias to negative emotional information.MethodWe used questionnaires and experiments to explore the improvement effect of ABM training on social anxiety in college students. In Study 1, we used dot-probe tasks to investigate the attentional bias to negative emotional information and the relationship with social anxiety severity in college students. In Study 2, college students with high social anxiety were divided into two groups: attentional bias modification training task group (ABM) and attention control condition task group (ACC). The ABM group received a continuous intervention for 10 days to observe changes in social anxiety levels and attentional bias scores in the pretest and posttest stages.ResultsThe results showed that the correlation of attentional bias to negative emotional information and social anxiety severity was significant. Meanwhile, the high social anxiety participants responded more quickly to negative emotional information. After the intervention, social anxiety levels and attentional bias scores of the training group were significantly reduced.ConclusionsThe results showed that attentional bias modification training can reduce attentional bias to negative emotional information in college students with social anxiety and effectively improve their social anxiety.

Keeping the time: the impact of external clock-speed manipulation on time-based prospective memory

Several studies have suggested that time monitoring is important for appropriate time-based prospective memory (TBPM). However, it is still unknown if people actively use internal timing processes to monitor the approaching target time, and whether they do so by tracking the duration between clock digits, or by counting and matching the numerical progression of clock ticks' digits with the target time. Therefore, in the present study, we investigated whether a manipulation of the external time affected time monitoring and TBPM performance. In two experiments, participants performed two identical TBPM tasks: a first TBPM block with no clock-speed manipulation followed by a second TBPM block, where the clock-speed was manipulated as faster or slower (experimental conditions) or normal (control condition). The results showed that only participants in the slower clock condition increased time monitoring in the second compared to the first TBPM block (d = 0.42 and 1.70); moreover, particularly in Experiment 2, participants in the faster clock condition checked the clock significantly less frequently than participants in the slower clock (d = -1.70) and in the control condition (d = -0.98), but only during the 4th minute. No effect was found for TBPM performance. Overall, results suggested that people tracked the target time by counting and matching the numerical progression of clock ticks' digits with the target time. The findings are discussed considering the most recent theoretical advancements about the relationship between time perception and TBPM.

Lipoprotein lipase as a target for obesity/diabetes related cardiovascular disease

Worldwide, the prevalence of obesity and diabetes have increased, with heart disease being their leading cause of death. Traditionally, the management of obesity and diabetes has focused mainly on weight reduction and controlling high blood glucose. Unfortunately, despite these efforts, poor medication management predisposes these patients to heart failure. One instigator for the development of heart failure is how cardiac tissue utilizes different sources of fuel for energy. In this regard, the heart switches from using various substrates, to predominantly using fatty acids (FA). This transformation to using FA as an exclusive source of energy is helpful in the initial stages of the disease. However, over the progression of diabetes this has grave end results. This is because toxic by-products are produced by overuse of FA, which weaken heart function (heart disease). Lipoprotein lipase (LPL) is responsible for regulating FA delivery to the heart, and its function during diabetes has not been completely revealed. In this review, the mechanisms by which LPL regulates fuel utilization by the heart in control conditions and following diabetes will be discussed in an attempt to identify new targets for therapeutic intervention. Currently, as treatment options to directly target diabetic heart disease are scarce, research on LPL may assist in drug development that exclusively targets fuel utilization by the heart and lipid accumulation in macrophages to help delay, prevent, or treat cardiac failure, and provide long-term management of this condition during diabetes.

Smartphone usage during walking decreases the positive persistency in gait cycle variability

Gait cycle variability during steady walking, described by the stride interval time series, has been used as a gait-stability-related measure. In particular, the positive persistency in the stride intervals with 1/f-like fluctuation and reduction of the persistency are the well-documented metrics that can characterize gait patterns of healthy young adults and elderly including patients with neurological diseases, respectively. Here, we examined effects of a dual task on gait cycle variability in healthy young adults, based on the mean and standard deviation statistics as well as the positive persistency of the stride intervals during steady walking on a treadmill. Specifically, three gait conditions were examined: control condition, non-cognitive task with holding a smartphone in front of the chest using their dominant hand and looking fixedly at a blank screen of the smartphone, and cognitive motor task with holding a smartphone as in the non-cognitive task and playing a puzzle game displayed on the smartphone by one-thumb operation. We showed that only the positive persistency, not the mean and standard deviation statistics, was affected by the cognitive and motor load of smartphone usage in the cognitive condition. More specifically, the positive persistency exhibited in the control and the non-cognitive conditions was significantly reduced in the cognitive condition. Our results suggest that the decrease in the positive persistency during the cognitive task, which might represent the deterioration of healthy gait pattern, is caused endogenously by the cognitive and motor load, not necessarily by the reduction of visual field as often hypothesized.

The role of psychological formulation in inpatient settings in supporting staff empathy and therapeutic optimism for adults diagnosed with borderline personality disorder: A pre- and post-vignette study.

OBJECTIVES: National Health Service (NHS) values, such as empathy and therapeutic optimism, are integral when supporting service users with complex mental health presentations. There is some evidence to suggest that psychological formulation can increase empathy and optimism in healthcare professionals. This study, therefore, aimed to investigate whether a psychological formulation of a hypothetical service user with a complex presentation, typically labelled with a diagnosis of borderline personality disorder (BPD), increased empathy and therapeutic optimism in professionals working in mental health inpatient services. Sixty-six mental health professionals working in NHS inpatient services took part in a pre- and post-vignette study. Participants were asked to read a case vignette about a hypothetical service user, with a diagnostic label of BPD, and complete questionnaires capturing levels of empathy and therapeutic optimism. Participants were then randomized into two conditions and either asked to read the same information again (control condition) or read a psychological formulation based on the same hypothetical service user (intervention condition). The findings were analysed using a series of ANCOVAs/ANCOHETs. Two constructs of empathy (i.e. perspective taking and empathic concern), and therapeutic optimism significantly increased following exposure to the psychological formulation when compared to the control group condition. This study warrants further replication. These initial findings; however, indicate that psychological formulation can significantly increase the ability to perspective take, display empathic concern, and hold therapeutic optimism towards service users with a presentation associated with a diagnosis of BPD.

Temporal gamma tACS and auditory stimulation affect verbal memory in healthy adults.

Research suggests a potential of gamma oscillation entrainment for enhancing memory in Alzheimer's disease and healthy subjects. Gamma entrainment can be accomplished with oscillatory electrical, but also sensory stimulation. However, comparative studies between sensory stimulation and transcranial alternating current stimulation (tACS) effects on memory processes are lacking. This study examined the effects of rhythmic gamma auditory stimulation (rAS) and temporal gamma-tACS on verbal long-term memory (LTM) and working memory (WM) in 74 healthy individuals. Participants were assigned to two groups according to the stimulation techniques (rAS or tACS). Memory was assessed in three experimental blocks, in which each participant was administered with control, 40, and 60 Hz stimulation in counterbalanced order. All interventions were well-tolerated, and participants reported mostly comparable side effects between real stimulation (40 and 60 Hz) and the control condition. LTM immediate and delayed recall remained unaffected by stimulations, while immediate recall intrusions decreased during 60 Hz stimulation. Notably, 40 Hz interventions improved WM compared to control stimulations. These results highlight the potential of 60 and 40 Hz temporal cortex stimulation for reducing immediate LTM recall intrusions and improving WM performance, respectively, probably due to the entrainment of specific gamma oscillations in the auditory cortex. The results also shed light on the comparative effects of these neuromodulation tools on memory functions, and their potential applications for cognitive enhancement and in clinical trials.

Heat waves induce milkweed resistance to a specialist herbivore via increased toxicity and reduced nutrient content.

Over the last decade, a large effort has been made to understand how extreme climate events disrupt species interactions. Yet, it is unclear how these events affect plants and herbivores directly, via metabolic changes, and indirectly, via their subsequent altered interaction. We exposed common milkweed (Asclepias syriaca) and monarch caterpillars (Danaus plexippus) to control (26:14°C, day:night) or heat wave (HW) conditions (36:24°C, day:night) for 4 days and then moved each organism to a new control or HW partner to disentangle the direct and indirect effects of heat exposure on each organism. We found that the HW directly benefited plants in terms of growth and defence expression (increased latex exudation and total cardenolides) and insect her'bivores through faster larval development. Conversely, indirect HW effects caused both plant latex and total cardenolides to decrease after subsequent herbivory. Nonetheless, increasing trends of more toxic cardenolides and lower leaf nutritional quality after herbivory by HW caterpillars likely led to reduced plant damage compared to controls. Our findings reveal that indirect impacts of HWs may play a greater role in shaping plant-herbivore interactions via changes in key physiological traits, providing valuable understanding of how ecological interactions may proceed in a changing world.

Habitual Caffeine Use is Associated with Heightened Cortisol Reactivity to Lab-Based Stress in Two Samples.

Habitual caffeine consumption protects against depression, but through unclear mechanisms. Although habitual caffeine use predicts cortisol release to other acute stressors (e.g., exercise), this is less examined with lab-based psychosocial stress in healthy adults. Further, caffeine-induced cortisol increases may mask theory-predicted cortisol blunting to robust stress in people with elevated depression risk. In two samples, we tested whether acute (same-day) and habitual caffeine use would predict greater cortisol reactivity to lab-based stress, and whether caffeine would "mask" the effect of a depression risk factor, trait rumination, on blunted cortisol reactivity. In Sample 1, N = 128 emerging adults completed one of three Trier Social Stress Test conditions: non-evaluative Control, ambiguously evaluative Intermediate, or explicit Negative Evaluative. In Sample 2, N = 148 emerging adults completed either a Control or Negative Evaluative condition. In both samples, multilevel growth curve modeling indicated habitual (t = -1.99, p = .048; t = -2.73, p = .007, Samples 1 and 2 respectively), but not acute caffeine use predicted heightened cortisol reactivity as a function of condition. In Sample 1, the relationship between condition, rumination, and blunted cortisol was evident only in caffeine non-users, which differed from users (t = 2.82, p = .005), but in Sample 2 the predicted blunting pattern was evident regardless of caffeine use. This provides evidence that habitual caffeine use is associated with greater cortisol release under psychosocial lab-based stress and may mask the influence of psychosocial variables; future research should examine whether habitual caffeine-induced cortisol release has behaviorally activating effects that protect against depression.

Sextuple knockouts of a highly conserved and coexpressed AUXIN/INDOLE-3-ACETIC ACID gene set confer shade avoidance-like responses in Arabidopsis.

AUXIN/INDOLE-3-ACETIC ACIDs are transcriptional repressors for auxin signalling. Aux/IAAs of Arabidopsis thaliana display some functional redundancy. The IAA3/SHY2 clade (IAA1, IAA2, IAA3and IAA4) show strong sequence similarity, but no higher-order mutants have been reported. Here, through CRISPR/Cas9 genome editing, we generated loss-of-function iaa1/2/3/4 mutants. The quadruple mutants only exhibited a weak phenotype. Thus, we additionally knocked out IAA7/AXR2 and IAA16, which are coexpressed with IAA1/2/3/4. Remarkably, under white light control conditions, the iaa1/2/3/4/7/16 mutants exhibited a shade avoidance-like phenotype with over-elongated hypocotyls and petioles and hyponastic leaves. The sextuple mutants were highly sensitive to low light intensity, and the hypocotyl cells of the mutants were excessively elongated. Transcriptome profiling and qRT-PCR analyses revealed that the sextuple mutation upregulated IAA19/MSG2 and IAA29, two shared shade/auxin signalling targets. Besides, genes encoding cell wall-remodelling proteins and shade-responsive transcription regulators were upregulated. Using dual-luciferase reporter assays, we verified that IAA2/IAA7 targeted the promoters of cell wall-remodelling genes to inhibit their transcription. Our work indicates that the IAA1/2/3/4/7/16 gene set is required for the optimal integration of auxin and shade signalling. The mutants generated here should be valuable for exploring the complex interactions among signal sensors, transcription activatorsand transcription repressors during hormone/environmental responses.

A 10-min reduction in cerebral blood flow does not alter post-intervention executive function: evidence from lower-body negative pressure.

A single bout of exercise as well as exposure to a hypercapnic environment increases cerebral blood flow (CBF) and is an adaptation linked to a post-intervention executive function (EF) benefit. In the present investigation we sought to determine whether a transient reduction in CBF impairs EF. Accordingly, we employed 10-min -30 mmHg and -50 mmHg lower-body negative pressure (LBNP) interventions as well as a non-LBNP control condition. LBNP was employed because it sequesters blood in the lower legs and safely and reliably decreases CBF. Transcranial Doppler ultrasound was used to measure middle cerebral artery velocity (MCAv) to estimate CBF prior to and during LBNP conditions. As well, assessments of the inhibitory control component of EF (i.e., antipointing) were completed prior to (pre-) and immediately after (i.e., post-) each condition. Antipointing requires that an individual reach mirror-symmetrical to an exogenously presented target and is a task providing the resolution to detect subtle EF changes. Results showed that LBNP produced a 14% reduction in MCAv; however, null hypothesis, equivalence and Bayesian contrasts indicated that antipointing metrics did not vary from pre- to post-intervention, and LBNP-based changes in MCAv magnitude were not reliably correlated with antipointing planning times. Hence, a 10-min reduction in CBF did not impact the efficiency or effectiveness of an inhibitory control measure of EF.

Randomized Controlled Trial Evaluating the Effectiveness of a Direct-to-Consumer Marketing Video About Patients' Right to Evidence-Based Mental Health Care.

This study evaluated the impact of a direct-to-consumer (DTC) marketing video designed to educate the public about patients' rights to evidence-based mental health care (EBMHC). Participants (N = 632) were randomly assigned to an active DTC video condition, a control video condition, or a control condition without a video. Participants who watched the DTC video (vs. both control conditions) had significantly greater knowledge of patients' rights to EBMHC. Further, individuals who watched the DTC (vs. control) video reported significantly greater comfort with accessing care and perceived their assigned video as significantly more culturally sensitive. However, participants who watched the DTC video were not significantly different from both control conditions on self-report measures of self-efficacy in working with a provider, likelihood of asking a provider about one's rights, treatment-seeking intentions, and self-stigma. Findings suggest the potential for a DTC video to promote knowledge of EBMHC, though its impact on help-seeking perceptions and intentions was less promising.

Assessing the feasibility, acceptability, and initial efficacy of a multiple behavior change intervention addressing alcohol use, sexual risk taking, and bystander intervention.

Prevention programs that address the intersecting health problems of risky alcohol use, unsafe sexual behaviors, and sexual violence are needed. This pilot project assessed the feasibility, acceptability, and preliminary efficacy of a two-session group-based intervention, Sex Positive Lifestyles: Addressing Alcohol & Sexual Health (SPLASH), targeting these highly interconnected risks for college students across genders. A total of 217 participants (51.6% male, ages 18-24) took part in the SPLASH intervention or a nutrition/exercise control condition. SPLASH included three approaches aimed at reducing the incidence of alcohol problems, unsafe sex, and sexual victimization: normative feedback to modify misperceptions around peers' drinking, sexual behaviors, and support of bystander intervention; drinking and sexual-related protective behavioral strategy training to enhance safer drinking and sex-risk behaviors; and bystander intervention skills training to promote bystander efficacy and engagement. Participants completed baseline and follow-up (1-month and 6-month) online assessments. SPLASH demonstrated high acceptability and feasibility, as well as preliminary efficacy. SPLASH participants reported strong acceptability of the intervention, particularly its integrated content and interactive, in-person group format. Successful enrollment (70% randomized) and retainment point to the feasibility of recruiting students to this two-session in-person intervention. Results showed sustained trends toward more accurate perceived sex-related norms and indications of increasing bystander norms among intervention but not control participants. Results demonstrate the potential for SPLASH to effectively address the interrelated health risks of risky alcohol use, unsafe sex, and sexual violence on college campuses and point to the need for larger-scale studies.

Exploring the effect of cognitive load in scenarios of daily driving

AbstractAlthough driving to and from work is an unavoidable part of the working life of many people, little is known about the relationship between work-related and drive-related cognitive load in daily commuting. To explore those relationships, Study 1 examined the effect of a demanding driving period on the performance of a subsequent cognitive task (mimicking a home-to-work commuting scenario). That driving-related higher cognitive load than the control condition was associated with an increased accuracy in the following cognitive task. Study 2 examined the effects of a period of demanding cognitive tasks on the performance of a subsequent driving task (mimicking a work-to-home commuting scenario). Although no reliable effect on speed or lane keeping ability in a virtual motorway scenario was observed, the completion of tasks under the higher cognitive load condition before driving led to a modest increase in the distance kept from the car ahead. The two sets of findings suggest that moderate levels of cognitive load could modulate the performance in timely contiguous tasks. The process underpinning possible spillover effects with such timestamp is unknow but might be linked to the activation of long-lasting attentional processes involving alertness. Hence, this exploratory study can be a catalyst for future studies investigating the interplay between cognitive load and driving in scenarios of daily commuting.

Testing and evaluation of light clothing properties used in fire and rescue service units

In the testing room for examination products of the Fire Engineering and Expert Institute (FEEI) of the Ministry of the Interior of the Slovak Republic in Bratislava, the Slovak National Accreditation Service SNAS has granted accreditation. Accredited testing room with identification number no. S-084 performs tests applied in the field of personal protective equipment. The goal is to specify, determine, and, above all, verify the selected characteristics for emergency clothing (light emergency clothing - LEC) used by firefighters and rescuers in the Fire and Rescue Service units to determine the conditions for procurement and quality control of the LEC supplied. The results obtained during the examination of the properties of light emergency clothing will be used in the next steps of the research of the Product Assessment Department (PAD) FEEI of the Ministry of the Interior of the Slovak Republic. In contrast, individual parameters can be used to design new LEC. The basic meaning and purpose of any protective means are to protect a person who intervenes in a dangerous environment contaminated with chemical, biological or radioactive substances, for example, in industrial accidents connected with the release of dangerous substances (HAZMAT), in accidents of vehicles transporting HAZMAT and natural disasters or fires of various nature. Protecting from the external environment is one of the favourable inherent properties of personal protective work equipment (PPE).

Receptor-like cytoplasmic kinase 58 reduces tolerance of maize seedlings to low magnesium via promoting H2O2 over-accumulation.

ZmRLCK58, a negative growth regulator, reduces tolerance of maize seedlings to low Mg via enhancing H2O2 accumulation in the shoot. Magnesium (Mg) deficiency is one of critical limiting factors for crop production in widespread acidic soils worldwide. However, the molecular mechanism of crop response to Mg deficiency is still largely unclear. Here, we found higher concentrations of H2O2, soluble sugars, and starch (1.5-, 1.9-, and 1.4-fold, respectively) in the shoot of low-Mg-treated maize seedlings, compared with Mg sufficient plants under hydroponic culture. Consistent with over-accumulation of H2O2, transcriptome profiling revealed significant enrichment of 175 differentially expressed genes (DEGs) in "response to oxygen-containing compound" out of 641 DEGs in the shoot under low Mg. Among 175 DEGs, a down-regulated receptor-like cytoplasmic kinase ZmRLCK58 underwent a recent duplication event before Poaceae divergence and was highly expressed in the maize shoot. ZmRLCK58 overexpression enhanced H2O2 accumulation in shoots by 21.3% and 29.8% under control and low-Mg conditions, respectively, while reducing biomass accumulation compared with wild-type plants. Low Mg further led to 39.7% less starch accumulation in the ZmRLCK58 overexpression shoot and lower Mg utilization efficiency. Compared with wild-type plants, overall down-regulated expression of genes related to response to carbohydrate, photosynthesis, H2O2 metabolic, oxidation-reduction, and ROS metabolic processes in ZmRLCK58 overexpression lines preconditioned aforementioned physiological alterations. Together, ZmRLCK58, as a negative growth regulator, reduces tolerance of maize seedlings to low Mg via enhancing H2O2 accumulation.

Comparison of the Effects of a Roller Massager Intervention on the Rectus Femoris Between Lengthened and Slack Positions.

Kasahara, K, Konrad, A, Murakami, Y, Thomas, E, and Nakamura, M. Comparison of the effects of a roller massager intervention on the rectus femoris between lengthened and slack positions. J Strength Cond Res XX(X): 000-000, 2024-A roller massager (RM) is a type of foam rolling device, which previous studies have shown to be effective for acutely decreasing tissue hardness and increasing range of motion (ROM). However, these effects may differ with the RM intervention position (i.e., knee flexion or knee extension). Therefore, this study aimed to compare the acute effects of an RM intervention on the rectus femoris (RF) in the knee flexed and extended positions. The subjects were 14 healthy male college students (age, 22.6 ± 0.8 years). The RF of the dominant leg was tested. Three conditions were compared: a control condition with no intervention (CON), an RM intervention in knee extension (i.e., RM_extension), and a RM intervention in knee flexion (i.e., RM_flexion). The measurements were tissue hardness in the proximal (TH_pro), middle (TH_mid), and distal (TH_dis) portions of the RF, knee flexion ROM, pain pressure threshold (PPT), maximal voluntary isometric contraction (MVC-ISO) torque, and maximal voluntary concentric contraction (MVC-CON) torque in the RF before and immediately after the intervention. There were significant interaction effects of TH_mid and knee flexion ROM. Both RM_extension and RM_flexion conditions showed a significant (p < 0.01) decrease in TH_mid and an increase in knee flexion ROM, but there were no significant differences between conditions. There was a main effect for TH_pro and PPT (p < 0.05) but no significant interaction effect or main effect for TH_dis, MVC-ISO torque, and MVC-CON torque. The results showed that the RM intervention can effectively decrease tissue hardness and increase ROM, regardless of limb position (i.e., knee extension or flexion).