Publications by authors named "Natalie Holt"

The optimum length for force generation () increases as activation is reduced, challenging classic theories of muscle contraction. Although the activation dependence of is seemingly consistent with length-dependent Ca sensitivity, this mechanism cannot explain the apparent force dependence of or the effect of series compliance on activation-related shifts in . We have tested a theory proposing that the activation dependence of relates to force depression resulting from shortening against series elasticity.

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The jaw muscles of the southern alligator lizard, Elgaria multicarinata, are used in prolonged mate-holding behavior, and also to catch fast prey. In both males and females, these muscles exhibit an unusual type of high endurance known as sustained force in which contractile force does not return to baseline between subsequent contractions. This phenomenon is assumed to facilitate the prolonged mate-holding observed in this species.

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AbstractMuscle-tendon unit (MTU) morphology and physiology are likely major determinants of locomotor performance and therefore Darwinian fitness. However, the relationships between underlying traits, performance, and fitness are complicated by phenomena such as coadaptation, multiple solutions, and trade-offs. Here, we leverage a long-running artificial selection experiment in which mice have been bred for high levels of voluntary running to explore MTU adaptation, as well as the role of coadaptation, multiple solutions, and trade-offs, in the evolution of endurance running.

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Article Synopsis
  • Muscle performance is crucial for animal movement and greatly influences behavior, ecology, and evolution, making it important to analyze muscle dynamics from a mechanical perspective.
  • Traditional biomechanics focused on muscle work capacity (Wmax), but recent research emphasizes the importance of muscle power capacity and introduces a new constraint based on kinetic energy capacity (Kmax), which is linked to muscle shortening speed.
  • The ratio of Kmax to Wmax defines a similarity index (Γ), suggesting a shift in understanding musculoskeletal dynamics and inspiring new hypotheses about how evolutionary adaptations shape muscle design.
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Skeletal muscle powers animal movement through interactions between the contractile proteins, actin and myosin. Structural variation contributes greatly to the variation in mechanical performance observed across muscles. In vertebrates, gross structural variation occurs in the form of changes in the muscle cross-sectional area : fibre length ratio.

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Background While several studies have suggested that anesthesia and surgical care episodes provide an opportunity to improve the diagnosis and treatment of hypertension, few studies have implemented and tested pragmatic care coordination efforts for this population. The present study aimed to examine the effects of same-day primary care referral vs. usual care on outpatient hypertension treatment among patients with elevated preoperative clinic blood pressure (BP).

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Purpose: The sociopolitical context in which transgender and gender-diverse (TGD) people live has significant effects on mental health. We examined whether perceptions of context (TGD people's perceptions of how TGD people were viewed) differed across four United States (U.S.

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The field of behavioral neuroendocrinology has only begun to explore the lived experiences of transgender and gender diverse (TGD) people exposed to stigma. In light of escalating attacks and legislation targeting TGD people in the United States, it is crucial to examine the physiological pathways through which gender minority stressors become embodied, impact health, and contribute to health inequities. The Trans Resilience and Health Study included baseline data collection from fall 2019 to spring 2020 from a sample of 124 TGD people, reflecting a diversity of gender identities (e.

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Background: Veterans Affairs (VA) implemented the Veteran-centered Whole Health System initiative across VA sites with approaches to implementation varying by site.

Purpose: Using the Consolidated Framework for Implementation Research (CFIR), we aimed to synthesize systemic barriers and facilitators to Veteran use with the initiative. Relevance to healthcare quality, systematic comparison of implementation procedures across a national healthcare system provides a comprehensive portrait of strengths and opportunities for improvement.

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Ensuring that mental health professionals are appropriately trained to provide affirming and sensitive care to transgender and gender diverse (TGD) adults is one mechanism that may reduce the marginalization sometimes experienced by TGD adults in mental health contexts. In this study, mental health professionals (n=142) completed an online survey documenting the sources and types of training received to provide TGD-sensitive care; and, shared a self-assessment of their comfort, competence, and ability to provide TGD-sensitive care. Findings revealed that the majority of the mental health professionals in the study (approximately 81%) received specific training to work with TGD clients from a variety of sources.

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Transgender and gender diverse (TGD) individuals often must undergo a psychosocial assessment and receive a letter of support from a mental health care provider to access gender-affirming medical care (GAMC). This study describes TGD individuals' perceptions of barriers and benefits of the assessment process and uses thematic analysis to explore TGD individuals' opinions on how mental health care should or should not be related to gender-affirming medical care. Two hundred and eighteen TGD participants completed an online survey.

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Objective: Geographic location can affect access to appropriate, affirming mental health care for sexual and gender minority (SGM) individuals, especially for those living in rural settings. Minimal research has examined barriers to mental health care for SGM communities in the southeastern United States. The objective of this study was to identify and characterize perceived barriers to obtaining mental health care for SGM individuals living in an underserved geographic area.

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Purpose Of Review: We describe recent research regarding access to affirming mental health services for transgender and gender-diverse (TGD) adults and explore new resources available for therapists to inform evidence-based practice with TGD clients.

Recent Findings: Barriers and facilitators at all socioecological levels impact TGD adults' mental health help-seeking. TGD adults often interface with mental health providers while accessing gender-affirming medical care, though new standards of care are likely to alter this typically common path to mental health services.

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A trade-off between locomotor speed and endurance occurs in various taxa, and is thought to be underpinned by a muscle-level trade-off. Among four replicate high runner (HR) lines of mice, selectively bred for voluntary wheel-running behavior, a negative correlation between average running speed and time spent running has evolved. We hypothesize that this trade-off is due to changes in muscle physiology.

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Latinx immigrants experience substantial disparities in mental health treatment access, particularly for posttraumatic stress disorder (PTSD). The availability of brief, flexible interventions in Spanish may assist in reducing these disparities. Written Exposure Therapy (WET) is a five-session PTSD intervention that appears as effective as longer, gold-standard interventions, but has yet to be tested among Latinx immigrants.

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Lesbian, gay, bisexual, transgender, queer, and other sexual and gender minority (LGBTQ+) individuals experience health inequities and barriers to accessing appropriate, affirming care. Little is known about differing health care experiences within the LGBTQ+ population, particularly among individuals living in underserved areas. This study explored health care experiences and utilization among LGBTQ+ subgroups: lesbian and gay cisgender individuals (n = 258), bisexual+ cisgender individuals (n = 71), and transgender and gender-diverse individuals (n = 80).

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Individuals who identify as transgender or gender diverse (TGD) are presenting at mental health clinicians' offices with increasing frequency. Many TGD clients are seeking care related to affirming their gender identity but also may present with anxiety, depression, trauma, substance abuse, or other problems for which a clinician may commonly provide services. Some clinicians may hesitate to accept TGD clients into their practice if they have little specialized training to work with this population in an affirming manner, especially in more underserved areas where a generalist practice is the norm.

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Objective: Transgender and gender diverse (TGD) people face various challenges when seeking therapy. Given this, we wanted to understand more about TGD people's perceptions of providers and how these compare to researcher ratings of providers on metrics of affirming practice.

Method: The sample included 158 TGD adults ( = 33.

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Movement is an integral part of animal biology. It enables organisms to escape from danger, acquire food, and perform courtship displays. Changing the speed or vertical position of a body requires mechanical energy.

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Treatments of Posttraumatic Stress Disorder (PTSD) often evidence high rates of dropout, ranging from 25% to 40%, among English-speaking samples. Written Exposure Therapy (WET), a novel manualized treatment for PTSD, evidences lower dropout rates and noninferiority to CPT, one of the most efficacious interventions for PTSD. Spanish-speaking Latinxs often experience greater dropout and barriers to care.

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There is a growing literature of clinical recommendations for transgender and gender diverse (TGD) affirming behavioral health care, yet it is unknown to what extent these recommendations are rooted in evidence-based practice (EBP). This systematic review included 65 articles published between 2009 and 2018 with recommendations for behavioral health services with TGD adults, emphasizing general clinical care. Coded variables included type of article, participant demographics, aspects of EBP, and whether care was informed by objective assessment.

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Recommendations for health care providers working with transgender and gender diverse (TGD) individuals emphasize affirming clients' identities, such as using correct pronouns and name, however it is unknown how often gender specialists adhere to such recommendations. Websites and intake forms of gender specialists were coded for use of affirming language, asking for pronouns and chosen name, and mention of TGD specialties and resources. Most websites identified the provider's specialty to work with TGD individuals, though much fewer provided additional resources concerning TGD issues and only half of intake forms included affirming language.

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