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Trauma-informed care (TIC) is the practice of consciousness and awareness of trauma that guides educators in developing academic and behavioral support for students with exceptionalities who have experienced trauma. TIC can support students from the lens of Positive Behavioral Intervention Supports (PBIS) and Social Emotional Learning (SEL) within Multi-Tiered Systems of Support (MTSS). The purpose of this article is to explore the integration of TIC practices within classrooms that utilize the MTSS framework and to assist pre-service and in-service teachers with implementing TIC practices within inclusive and restrictive K-12 learning environments.

Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and Wildlife Service (USFWS) to streamline ESA decisions include multispecies recovery plans and habitat conservation plans. We address species status assessment (SSA), a USFWS process to inform ESA decisions from listing to recovery, within the context of multispecies and ecosystem planning. Although existing SSAs have a single-species focus, ecosystem-based research can efficiently inform multiple SSAs within a region and provide a foundation for transition to multispecies SSAs in the future. We considered at-risk grassland species and ecosystems within the southeastern United States, where a disproportionate number of rare and endemic species are associated with grasslands. To initiate our ecosystem-based approach, we used a combined literature-based and structured World Café workshop format to identify science needs for SSAs. Discussions concentrated on 5 categories of threats to grassland species and ecosystems, consistent with recommendations to make shared threats a focus of planning under the ESA: (1) habitat loss, fragmentation, and disruption of functional connectivity; (2) climate change; (3) altered disturbance regimes; (4) invasive species; and (5) localized impacts. For each threat, workshop participants identified science and information needs, including database availability, research priorities, and modeling and mapping needs. Grouping species by habitat and shared threats can make the SSA process and other planning processes for conservation of at-risk species worldwide more efficient and useful. We found a combination of literature review and structured discussion effective for identifying the scientific information and analysis needed to support the development of multiple SSAs. Article impact statement: Species status assessments can be improved by an ecosystem-based approach that groups imperiled species by shared habitats and threats.Mejoramiento de la Evaluación del Estado de una Especie bajo el Acta de Especies en Peligro de los Estados Unidos y Sus Consecuencias para los Retos de la Conservación Multiespecie a Nivel Mundial Resumen A pesar de su éxito, el Acta de Especies en Peligro de los E.U.A. (AEP) ha sido un reto de implementación por las limitaciones en su financiamiento, el retraso en la carga de trabajo y otros problemas. Conforme se intensifican las amenazas a la supervivencia de las especies y más especies resultan amenazadas, aumenta la necesidad de que la AEP y las políticas similares de otros países funcionen efectivamente. Los intentos por parte del Servicio Estadounidense de Pesca y Fauna (SEPF) para optimizar las decisiones de la AEP incluyen planes multiespecie de recuperación y planes de conservación de hábitat (PRH). Abordamos la evaluación del estado de las especies (EEE), un proceso del SEPF para orientar las decisiones del AEP desde el listado hasta la recuperación, dentro del contexto de la planeación multiespecie y de ecosistemas. Aunque las EEE existentes tienen un enfoque sobre una única especie, la investigación basada en el ecosistema puede orientar eficientemente a múltiples EEE dentro de una región y proporcionar una base para la transición a las EEE multiespecie en el futuro. Consideramos a las especies y los ecosistemas en riesgo de los pastizales del sureste de los Estados Unidos, en donde un número desproporcionado de especies raras y endémicas está asociado con los pastizales. Para iniciar nuestra estrategia basada en el ecosistema, usamos un formato de taller de World Café estructurado y basado en la literatura para identificar la necesidad de tener EEE. Las discusiones se centraron en cinco categorías de amenazas para las especies y ecosistemas de los pastizales, consistentes con las recomendaciones para volver a las amenazas compartidas un foco de la planeación bajo la AEP: (1) pérdida del hábitat, fragmentación y disrupción de la conectividad funcional; (2) cambio climático; (3) regímenes alterados de perturbación; (4) especies invasoras; y (5) impactos localizados. Para cada amenaza, los participantes del taller identificaron las necesidades científicas y de información, incluyendo la disponibilidad de bases de datos, prioridades de la investigación y necesidades de modelado y mapeado. La agrupación de las especies por hábitat y amenaza compartida puede hacer más eficientes y útiles el proceso de EEE y otros procesos de planeación de la conservación de especies en riesgo a nivel mundial. Encontramos una combinación de revisiones bibliográficas y discusiones estructuradas para identificar la información y el análisis necesarios para respaldar el desarrollo de múltiples EEE.尽管《美国濒危物种法案》 (U.S. Endangered Species Act, ESA) 已取得一定成功, 但由于资金限制、工作量积压及其它问题, 该法案的实施仍面临挑战。随着威胁的加剧和受到威胁的物种增加, 人们对于 ESA 及其它国家类似的保护法律和政策发挥有效作用的需求也越来越强烈。同时, 美国鱼类及野生动物管理局也在努力简化包括多物种恢复计划和栖息地保护计划在内的ESA决策过程。本研究以多物种和生态系统规划为背景, 进行了物种状态评估, 这是美国鱼类及野生动物管理局为物种从列入名录到恢复的一系列ESA决策提供信息的过程。现有的物种状态评估侧重于单一物种, 而基于生态系统的研究则可以有效地指导一个区域内多个物种状态评估过程, 并为未来向多物种状态评估过渡提供基础。本研究关注美国东南部濒危的草地物种和生态系统, 该地区草地稀有种和特有种的数量不成比例得高。为了实施基于生态系统的方法, 我们将基于文献和结构化世界咖啡馆研讨会的形式相结合, 以确定物种状态估计的科学需求。我们集中讨论了草地物种和生态系统面临的5类威胁, 并建议将共同存在的威胁作为ESA的规划重点, 这些威胁包括 (1) 栖息地丧失、破碎化和功能连接度中断; (2) 气候变化; (3) 干扰情况变化; (4) 入侵物种; (5) 局部地区的影响。研讨会参与者确定了每种威胁的科学需求和信息需求, 包括数据库可用性、优先研究内容以及建模和测绘需求。根据栖息地和共同威胁对物种进行分组, 可以使物种状态评估过程和全球其它濒危物种保护的规划过程更加有用和高效。我们发现, 将文献综述与结构化讨论相结合, 可以有效地确定支持多个物种状态评估发展所需的科学信息和分析。【翻译: 胡怡思; 审校: 聂永刚】.

Guided practice within explicit instruction has been shown to be an effective method for teaching academic and behavioral skills to students with emotional and behavioral disorders (EBD). The support provided through guided practice allows students to acquire new skills confidently and successfully. This article provides practitioners of students with and at risk for EBD steps for incorporating guided practice into their instructional routine.

Classroom management is cited as a frequent concern by many teachers. These concerns with classroom management are commonly rooted in a struggle to effectively engage students and a failure to form authentic relationships with students. Centering Culturally Relevant Pedagogy is crucial when effectively engaging and building authentic relationships with students – especially for Culturally and Linguistically Diverse students identified with Emotional Behavior Disorder (EBD). Mainly, teachers should hold a high self-efficacy of themselves and high expectations for their students, build and maintain authentic classroom communities, and demonstrate a passion for their work. Unfortunately, many teachers do not prioritize the need to be culturally responsive to their students’ families or the need to investigate their own cultural self-awareness. Additionally, these teachers often feel uninformed and ill-prepared to prioritize the aforementioned elements to successfully engage students in the classroom, as educator preparation programs often provide too little information, training, and reinforcement regarding the basics, as well as more specific strategies, of effective classroom management. Schools persistently fall short in providing an educational experience for students with EBD that leads to appropriate and desired educational outcomes due to a lack of teacher training in understanding the foundation and function of behavior, as well as how to appropriately address problematic behaviors. These shortcomings become particularly complex in classrooms with students with EBD, given the students’ multifaceted academic and social behavioral needs. Moreover, given the overrepresentation of African American males in the EBD disability category, the importance of specific cultural components cannot be ignored. Thus, when teachers do not structure their classroom culture in a manner that is Culturally Relevant, many students, especially African American male students with EBD, experience challenges meeting their goals to function properly in various environments—both in and out of the classroom. One strategy that teachers can use to improve their teaching of students with EBD is Classroom Management On-boarding (CMO-b). This paper identifies specific techniques that could guide the development of a plan for CMO-b that emphasizes the importance of the teacher-student relationship as the foundation for building a positive and effective classroom for teachers of students identified with EBD, and especially for African American male students.

Teacher praise is an evidence-based strategy shown to increase appropriate prosocial behavior and decrease disruptive behavior, particularly with elementary school age students. In this article, we provide direction and recommendations for using positive feedback with middle and high school students. A review of the research literature, guidelines for implementation, and online resources are presented, along with a case study example designed to apply the implementation guidelines in a secondary school setting.

The Council for Exceptional Children (CEC) recently released updated standards regarding how to determine whether any particular intervention may be deemed an evidence-based practice (EBP). As new criteria regarding the acceptance of any specific intervention as evidence-based become available, the question arises: Would the application of new standards to studies completed under the older guidelines result in changes to past conclusions? The current study examined if changes in EBP standards might change the classification of an exemplar practice that was previously designated as an EBP. In this case, we examined video modeling (VM), an accepted practice regarding skill acquisition in special education as an exemplar practice. In order to determine if the new CEC 2014 standards would impact a previously determined EBP finding, a re-examination of Bellini and Akullian's (2007) frequently cited meta-analysis that focused on VM as an intervention for individuals with autism spectrum disorders (ASD) was conducted. The results revealed that if Bellini and Akullian had conducted their review using updated CEC 2014 standards, VM applied to individuals with ASD would not have been classified as an EBP.

In this article, two instructional practices, Numbered Heads Together (NHT) and Carousel Brainstorming (CB), are discussed to guide instructors through the intentional practice of incorporating flexible groupings (CEC, HLP 17) in their daily instruction for the purpose of creating Culturally Relevant PK-12 Learning Communities for CLD Learners with Exceptionalities. Although NHT and CB are not the only approaches for implementing cooperative learning groups as an effective instructional tool, it is the authors’ premise that both practices successfully promote academic achievement and provide a positive, culturally relevant design for diverse learners, as well as a practitioner-friendly framework that is easily implemented. NHT and CB also serve as a means to provide students with a voice for their learning and to promote positive student behaviors. Regardless of the setting or identified disability, when facilitated with foresight and careful planning, evidence-based instructional best practices are supported, and inclusive course content is attained through the use of NHT and CB. Example lesson plans to intentionally incorporate both strategies are included within the article.

The current body of research on classroom environments identifies key proactive instructional strategies that when implemented effectively can reduce the likelihood of problematic behavioral incidents by students. One strategy known as active supervision has demonstrated positive outcomes across school settings, including classrooms, hallways, cafeterias, and playgrounds. In this article, authors provide a definition of active supervision, empirical support for its use, a detailed description of how to implement it, and resources for further study.

Note this manuscript has supplementary files that will only be available online and does not need to be included in the printed version. text for online abstract: The interpretation of behavior of from marginalized backgrounds is susceptible to prejudice, bias, and racist ideology. This is especially true when evaluations include subjective assessment of perceived challenging behaviors which has historically led to overrepresentation of student from marginalized backgrounds at-risk of or with an emotional disturbance. While Positive Behavior Intervention and Supports (PBIS) frameworks are increasingly used in schools to support students behaviorally and decrease the need for special education services, students of color continue to be overrepresented as needing supports within these frameworks. One possible cause for this overrepresentation is implicit bias in evaluation and intervention of behavior for marginalized students. In an effort to increase the cultural responsiveness of PBIS frameworks, we describe the incorporation of anti-racist actions and the concept of critical consciousness in evaluating student behavior.

Female athletes are at a greater risk for anterior cruciate ligament (ACL) injuries than males. Current training programs for ACL injury reduction focus on muscle strengthening, appropriate movement patterns, and balance training. However, there is limited research on effective strategies to teach youth female soccer athletes how to properly perform desired movements associated with a decreased risk of ACL injuries. Behavioral skills training (BST) programs have been shown to be effective in teaching a wide variety of skills, but research on applications to sports is limited. This study evaluated a BST package for teaching a stepwise agility program to 3 youth female soccer athletes that consisted of verbal instructions, modeling, rehearsal, and feedback, which included video replay. Results showed a significant improvement in the number of steps the participants performed correctly relative to baseline, as well as maintenance of skills at follow-up. Implications for coaches and athletes, as well as limitations and directions for future research, are discussed.

The current study examined the collateral effects of an antecedent intervention for decreasing speech volume on vocal stereotypy. After teaching the participant to use a conversational voice level by providing visual feedback from a decibel meter app, conversational voice levels were differentially reinforced in the presence of a green card. Differential effects in voice magnitude during a green-card condition and a no-card condition were demonstrated using an alternating-treatments design. Results showed a decrease in volume of speech during the green-card condition, an overall decrease in vocal stereotypy, and a decrease to zero levels in loud stereotypical vocalizations. The implications of these findings on the treatment of vocal stereotypy are discussed.

Previous research has shown that a classroom management package can be used to prevent challenging behaviors and promote positive student behavior. Replicating and extending previous resear...

Researchers have found that English teachers in the United States of America (USA) perceive providing writing instruction to students with emotional behavioral disorders (EBD) as a difficult task. This could be associated with the fact that students with EBD often work below skill level in the content area of writing compared to same age peers. Researchers continue to investigate interventions to increase academic outcomes for students with EBD. Utilizing a single case design, three middle school students with EBD were observed in a self-contained classroom to determine the effects of a traditional and technology based self-monitoring intervention focused on decreasing student off-task behaviors while increasing scores on writing assignments. The study took place in an urban school district within the Southeastern region of the USA. Results indicated that the first two intervention phases were equally as effective at reducing off-task behaviors. Additionally, the third intervention phase led to decreased off-task behaviors and increased writing scores for all students compared to the previous two phases. Social validity assessments indicated that the self-monitoring interventions were useful and relevant for teachers and students with EBD in the self-contained setting. Implications for teachers and educational researchers are discussed within this article.

In this article, the authors discuss how the emphasis on classroom-level Positive Behavior Interventions and Supports strategies can establish a foundation for an efficient classroom management program and be utilized as a resource. The strategies described are physical classroom, procedures and rules, explicit timing, and transition (PETT mnemonic). Each strategy can be particularly useful in assisting novice and veteran teachers provide instruction to students with emotional and behavioral disorders within inclusive or self-contained classrooms.

General education teachers, special education teachers, social workers, psychologists, and a myriad of specialists are responsible for delivering content to all students within inclusive environments. These educational teams continue to search for strategies that can be recommended or used in an inclusive environment. Researchers have discovered that an instructional strategy such as Numbered Heads Together (NHT) increases both academic and behavioral outcomes for students with and without disabilities. This article provides consultants, Response to Intervention (RtI) team members, and coteaching teams with a specific strategy of NHT that can be used by two or more professionals to develop lessons or deliver instruction using a coteaching or consultant approach with both professionals (consultant and general education teacher) assessing learner outcomes after the completion of the activity.

Federal mandates (Individuals With Disabilities Education Improvement Act, 2004; No Child Left Behind Act, 2001) require teachers to accommodate students with more diverse academic and behavioral needs in inclusive general educational settings. To assist general educators in meeting this instructional challenge, multi-tiered systems of support (MTSS) such as response to intervention (RtI) and positive behavior interventions and supports (PBIS) were established in schools nationwide. There is still a need, however, for classroom-based interventions with empirical support that are feasible to implement in whole-class settings and acceptable to teachers and students. Here, Numbered Heads Together (NHT), an alternative questioning strategy, is offered as a potentially effective Tier 1 intervention that can be used to improve student performance in general education classrooms. Extant research findings are described, procedures for using NHT in classroom settings are discussed, and future directions for research and practice are offered.

In common planning time (CPT), middle school educators have an opportunity to share their experience and expertise during a designated period. Common planning time is especially beneficial in the collaborative process in which special and general educators can address the needs of students with exceptionalities. This column provides an outline on the possible implementation and the virtual experience of CPT and also offers information on how special education topics can be incorporated within CPT.

Increased vascular stiffness is fundamental to hypertension, and its complications, including atherosclerosis, suggest that therapy should also be directed at vascular stiffness, rather than just the regulation of peripheral vascular resistance. It is currently held that the underlying mechanisms of vascular stiffness in hypertension only involve the extracellular matrix and endothelium. We hypothesized that increased large-artery stiffness in hypertension is partly due to intrinsic mechanical properties of vascular smooth muscle cells. After confirming increased arterial pressure and aortic stiffness in spontaneously hypertensive rats, we found increased elastic stiffness of aortic smooth muscle cells of spontaneously hypertensive rats compared with Wistar-Kyoto normotensive controls using both an engineered aortic tissue model and atomic force microscopy nanoindentation. Additionally, we observed different temporal oscillations in the stiffness of vascular smooth muscle cells derived from hypertensive and control rats, suggesting that a dynamic component to cellular elastic stiffness is altered in hypertension. Treatment with inhibitors of vascular smooth muscle cell cytoskeletal proteins reduced vascular smooth muscle cell stiffness from hypertensive and control rats, suggesting their participation in the mechanism. This is the first study demonstrating that stiffness of individual vascular smooth muscle cells mediates vascular stiffness in hypertension, a novel concept, which may elucidate new therapies for hypertension and for vascular stiffness.

Summary A spectral analysis approach was developed for detailed study of time-resolved, dynamic changes in vascular smooth muscle cell (VSMC) elasticity and adhesion to identify differences in VSMC from young and aged monkeys. Atomic force microscopy (AFM) was used to measure Young’s modulus of elasticity and adhesion as assessed by fibronectin (FN) or anti-beta 1 integrin interaction with the VSMC surface. Measurements demonstrated that VSMC cells from old vs. young monkeys had increased elasticity (21.6 kPa vs. 3.5 kPa or a 612% increase in elastic modulus) and adhesion (86 pN vs. 43 pN or a 200% increase in unbinding force). Spectral analysis identified three major frequency components in the temporal oscillation patterns for elasticity (ranging from 1.7 × 10−3 to 1.9 × 10−2 Hz in old and 8.4 × 10−4 to 1.5 × 10−2 Hz in young) and showed that the amplitude of oscillation was larger (P

The authors used an ABCBC design to compare the effects of a single-student response strategy and unison handraising strategy on a teacher and two middle school students (a targeted student and typical achieving student) during a 7th grade health science class. During baseline the teacher had high rates of redirections and low rates of praise statements and opportunities to respond. For the intervention conditions the teacher had slightly fewer redirections and increases in praise statements during unison handraising than during single-student responding. Both the targeted student and the typical achieving student demonstrated slightly higher, levels of on-task behavior, correct responses, and test score percentages during unison handraising compared with single-student responding. Furthermore, a discussion on study limitations, implications, and future research directions is included.

Rationale: Increased aortic stiffness, an important feature of many vascular diseases, eg, aging, hypertension, atherosclerosis, and aortic aneurysms, is assumed because of changes in extracellular matrix (ECM). Objective: We tested the hypothesis that the mechanisms also involve intrinsic stiffening of vascular smooth muscle cells (VSMCs). Methods and Results: Stiffness was measured in vitro both by atomic force microscopy (AFM) and in a reconstituted tissue model, using VSMCs from aorta of young versus old male monkeys ( Macaca fascicularis ) (n=7/group), where aortic stiffness increases by 200% in vivo. The apparent elastic modulus was increased ( P P Conclusions: These data support the novel concept, not appreciated previously, that increased vascular stiffness with aging is attributable not only to changes in ECM but also to intrinsic changes in VSMCs.

Previous research has demonstrated that Numbered Heads Together, a cooperative learning strategy, is more effective than traditional teacher-led instruction in academic areas such as social studies and science. The current study compared the effects of two types of Numbered Heads Together strategies with a baseline condition during 7th grade language arts lessons. Results indicated that three students with various disabilities had higher percent intervals of on-task behavior and daily quiz scores during either Heads Together condition. Teacher satisfaction ratings suggested that Heads Together was easy to implement, and all three students preferred this strategy to baseline instruction. A discussion of study limitations, implications, and future research directions is included.

Actin-myosin crossbridges form in a sarcomere under the control of calcium ions binding to the thin filament. Crossbridges first form weak attachments before they transform into strong bonds that generate force. An appropriately simplified model of this action is critical for developing higherlevel models of cardiac function. Models can be simplified by separating slower from faster processes, where the fast processes have achieved equilibrium. Processes in equilibrium can also be analyzed using the Ising model of statistical mechanics, which allows us to study a row of cooperatively interacting units - as occurs along the thin filament. Using these concepts, the sarcomere model was simplified to 3 states: (1) strong crossbridges attached to a regulatory unit (RU) on the thin filament that had calcium bound to it; (2) strong crossbridges attached to an RU without calcium; (3) an equilibrium mixture of detached and weakly attached crossbridges with and without calcium bound. This simplified model predicted steady-state relationships between force and calcium that reproduced the experimentally seen trend toward less cooperativity as force rises to more than half maximum. It also predicted a trend for clustering of strong crossbridges along the thin filament due to cooperative interactions.

A compact model of cardiac sarcomere dynamics is useful when developing integrated models of whole ventricular function. Kinetic models can be simplified by separating slower from faster processes. The representation of faster processes can then be reduced to their equivalent equilibrium relationships. Analysis of cooperativity within a cardiac sarcomere is also aided by dealing with equilibria, which can be analyzed using statistical thermodynamics. These principles guided the formulation of a compact kinetic model of cardiac sarcomere dynamics. In this scheme there were three slower processes: (1) reversible transitions between weak and strong crossbridges, (2) detachment of strong crossbridges, (3) dissociation of calcium from regulatory units (RUs) having a strong crossbridge. In the overall kinetic scheme, an individual RU could exist in 6 states: 3 states of crossbridge binding (none, weak, strong) interacting with 2 states of calcium binding (yes, no). Exchanges between the 4 states without strong crossbridges occurred by rapid equilibria. Thus, in the reduced model only 3 kinetic states remained: (1) strong crossbridges attached to RUs where calcium was bound, (2) strong crossbridges remaining attached even after calcium had dissociated, (3) the equilibrium mixture of the 4 remaining states. Since strong crossbridges appear to act independently, rate constants between these 3 states were considered independent of neighboring RUs. However, cooperativity between neighboring RUs exerted major impacts on the mixture of 4 states interacting rapidly as equilibria. Applying the linear Ising Model of statistical thermodynamics, the grand partition function characterizing interactions between neighboring RUs included activating effects from strong crossbridges as well as free calcium ions. This model predicted steady-state relationships between force and pCa (given as Hill plots) that reproduced the experimentally observed bend toward less cooperative slope near half activation.

Hypertension and aging are both recognized to increase aortic stiffness, but their interactions are not completely understood. Most previous studies have attributed increased aortic stiffness to changes in extracellular matrix proteins that alter the mechanical properties of the vascular wall. Alternatively, we hypothesized that a significant component of increased vascular stiffness in hypertension is due to changes in the mechanical and adhesive properties of vascular smooth muscle cells, and that aging would augment the contribution from vascular smooth muscle cells when compared with the extracellular matrix. Accordingly, we studied aortic stiffness in young (16-week-old) and old (64-week-old) spontaneously hypertensive rats and Wistar–Kyoto wild-type controls. Systolic and pulse pressures were significantly increased in young spontaneously hypertensive rats when compared with young Wistar–Kyoto rats, and these continued to rise in old spontaneously hypertensive rats when compared with age-matched controls. Excised aortic ring segments exhibited significantly greater elastic moduli in both young and old spontaneously hypertensive rats versus Wistar–Kyoto rats. were isolated from the thoracic aorta, and stiffness and adhesion to fibronectin were measured by atomic force microscopy. Hypertension increased both vascular smooth muscle cell stiffness and vascular smooth muscle cell adhesion, and these increases were both augmented with aging. By contrast, hypertension did not affect histological measures of aortic collagen and elastin, which were predominantly changed by aging. These findings support the concept that stiffness and adhesive properties of vascular smooth muscle cells are novel mechanisms contributing to the increased aortic stiffness occurring with hypertension superimposed on aging.

We review how deregulation, technological advance, and increased competitive rivalry have affected the size and health of the United States community banking sector and the quality and availability of banking products and services. We then develop a simple theoretical framework for analyzing how these changes have affected the competitive viability of community banks. Empirical evidence presented in this paper is consistent with the model’s prediction that regulatory and technological change has exposed community banks to intensified competition on the one hand, but on the other hand has left well-managed community banks with a potentially exploitable strategic position in the industry. We also offer an analysis of how the number and distribution of community banks may change in the future.

Experiments suggest that length changes alter activation in cardiac sarcomeres within a few milliseconds (Mateja & deTombe, 2012). Thus, the mechanism producing length-dependent activation must occur early in the contractile cycle, such as during the formation of weakly bound crossbridges. We hypothesized that a decrease in the energy required to form weak crossbridges would lead to greater probability of their formation. Such decrease in energy at longer sarcomere lengths could occur via reduction in both: (1) radial distance a crossbridge stretches to attach to actin, due to lattice spacing; (2) radial elastic crossbridge stiffness, due to influence of sarcomere length on modulators such as titin, myosin light chains, or myosin binding protein-C. We have previously developed a compact kinetic model of cardiac sarcomere dynamics (Hunter, BPS Meeting 2015). Parameters in this model were adjusted to produce the best fit with five experimental measures at constant sarcomere length (from others’ published data): (1) F-pCa relation, (2) alteration in F-pCa with addition of NEM-S1 strong crossbridges, (3) relation between kinetics of tension recovery and calcium concentration [k(TR)-pCa relation], (4) alteration in k(TR)-pCa with addition of NEM-S1, (5) shape of F-Ca loops during twitches. All five of these sets of experimental data were reasonably matched by the model using the best-fit set of parameters. Holding all other best-fit parameters constant, we then modified just the binding constant for weak crossbridges. An increased binding constant (due to lower energy to form a weak crossbridge) reproduced both of the following effects of increased sarcomere length: (1) shifted mid-point of F-pCa relation to lower [Ca++], (2) increased maximum force at saturating [Ca++]. Both of these experimental effects of increased sarcomere length are well known from published data (Dobesh, Konhilas, deTombe, 2002).

Although visco-elastic in general, the stress-strain relation of biomembranes is one-to-one or pseudo-elastic when being loaded after preconditioning. This pseudo-elastic relation is hypoelastic (i.e., it is not hyperelastic), yet much of the stress response can be characterized by a scalar function Ω that represents the work done (per unit reference volume) on the specimen during loading. (Since a pseudo-strain-energy function W is optimized to fit the test data and not the work done, Ω is not equal to W in general.) The remaining part tR of the stress response does no work during loading. With biaxial testing, Ω can be definitively determined from data. Moreover, for tests with the stretch directions coaxial to the axes of anisotropy, tR can be accurately characterized by a scalar function ω that depends on the strain. This paper is part 1 of 2 with “I. Theory” and “II. Application.”

This is the second paper of a 2 part series. In the first, a theoretical framework is developed that provides 3 enhancements for the constitutive theory of biomembranes. 1) Covariance amongst response terms is minimized, 2) the pseudo-strain-energy potential is redefined so as to be measurable, and 3) the stress response is decomposed into 2 parts—a hyperelastic part plus a hypoelastic-stress-residual. This paper illustrates the experimental advantages of this novel constitutive theory via analysis of biaxial test data obtained from chemically treated bovine pericardium.

This paper investigates the choice of financial advisors in mergers and acquisitions, the fees that the targets and the acquiring firms pay to these advisors, and the speed with which advisors complete transactions. Our sample includes 5337 merger deals announced during the period January 1995 to June 2000, that involved publicly traded targets and acquirers. We find that top-tier advisors are more likely to complete deals and to complete them in less time than lower tier advisors. However, the synergistic gains realized by the acquirers declined when top advisors were used. We also find that contingent fees play a significant role in expediting the deal completion. Surprisingly, we find that deals that are initiated by the advisors do not seem to take less time to complete. Our results suggest that the payment of larger advisory fees do not play an important role in determining the likelihood of completing the deal, but they are associated with greater acquisition gains realized by the acquirer. In addition, these synergistic gains are also associated with the switching by acquirers of their financial advisors within the same tier.

The ability of the Japanese stock market to appropriately price the riskiness of Japanese financial firms has been frequently questioned, particularly in light of Japan’s widespread financial distress in recent years and poor disclosure requirements. This paper examines the response in equity returns of Japanese banks to the failure of four commercial banks and two securities firms between 1995 and 1998. Using event study methodology, the analysis finds that share prices of surviving banks on the whole responded unfavorably to the failures and that financially weaker survivors were more adversely affected. This suggests that, despite the distress and alleged opaqueness, bank shareholders were able to use available indicators of financial condition both to incorporate new information quickly into stock prices and to differentiate among banks.

Central to this analysis is the identification of six rotation invariant scalars α 1–6 that succinctly define the strain in materials that have one family of parallel fibers arranged in laminae. These scalars were chosen so as to minimize covariance amongst the response terms in the hyperelastic limit, and they are termed strain attributes because it is necessary to distinguish them from strain invariants. The Cauchy stress t is expressed as the sum of six response terms, almost all of which are mutually orthogonal for finite strain (i.e. 14 of the 15 inner products vanish). For small deformations, the response terms are entirely orthogonal (i.e. all 15 inner products vanish). A response term is the product of a response function with its associated kinematic tensor. Each response function is a scalar partial derivative of the strain energy W with respect to a strain attribute. Applications for this theory presently include myocardium (heart muscle) which is often modeled as having muscle fibers arranged in sheets. Utility for experimental identification of strain energy functions is demonstrated by showing that common tests on incompressible materials can directly determine terms in W . Since the described set of strain attributes reduces the covariance amongst response terms, this approach may enhance the speed and precision of inverse finite element methods.

This paper provides a review of developments in the area of risk management at both the firm level and the macro-economy. We review rationales regarding why firms choose to manage risk, as well as new developments in measuring and managing risk in a dynamic setting. We also consider current risk sharing arrangements in light of the theory regarding optimal risk sharing. The paper concludes with some suggestions for additional research that emphasizes the importance of incorporating market incompleteness in an equilibrium setting. We also discuss the role of incompleteness at the macro-level and speculate on how derivatives markets may influence macro-economic stabilization policy.

A novel set of 5 strain invariants for materials exhibiting transversely isotropic behavior with respect to a reference configuration is developed through analysis of physical attributes of deformation. Experimental advantage for hyperelastic materials is demonstrated by showing that common tests can directly determine terms in W , the strain energy per unit reference volume. An analysis of symmetry allows the general form of W to be refined a priori. Moreover, this kinematics framework is potentially useful for solving inverse problems since the 5 response terms in the Cauchy stress t are mostly orthogonal (9 of the 10 mutual inner products vanish). For small deformation they are fully orthogonal (all 10 inner products vanish). A response term in t consists of an invariant response function multiplied by its associated kinematic tensor.

Some recent empirical evidence suggests that stock prices are not properly modeled as the present discounted value of expected dividends. In this paper, we estimate a present value model of stock price that is capable of explaining the observed long-term trends in stock prices. The model recognizes that firm managers control cash dividend payments. The model estimates indicate that stock price movements may be explained by managerial behavior.

A novel constitutive formulation is developed for finitely deforming hyperelastic materials that exhibit isotropic behavior with respect to a reference configuration. The strain energy per unit reference volume, W, is defined in terms of three natural strain invariants, K1–3, which respectively specify the amount-of-dilatation, the magnitude-of-distortion, and the mode-of-distortion. Distortion is that part of the deformation that does not dilate. Moreover, pure dilatation (K2=0), pure shear (K3=0), uniaxial extension (K3=1), and uniaxial contraction (K3=−1) are tests which hold a strain invariant constant. Through an analysis of previously published data, it is shown for rubber that this new approach allows W to be easily determined with improved accuracy. Albeit useful for large and small strains, distinct advantage is shown for moderate strains (e.g. 2–25%). Central to this work is the orthogonal nature of the invariant basis. If η represents natural strain, then {K1,K2,K3} are such that the tensorial contraction of (∂Ki/∂η) with (∂Kj/∂η) vanishes when i≠j. This result, in turn, allows the Cauchy stress t to be expressed as the sum of three response terms that are mutually orthogonal. In particular (summation implied) t=Ai∂W/∂Ki, where the ∂W/∂Ki are scalar response functions and the Ai are kinematic tensors that are mutually orthogonal.

This article investigates the impact of promotional expenditures or advertising on the performance and asset and liability characteristics of firms in the U.S. savings and loan industry over the period 1985 to 1989. The results of a simultaneous equation analysis on a sample of 2,534 thrifts in the Southeast region indicate that promotional expenditures had a strong positive impact on the profitability of their non-interest business activities. The promotional expenditures of thrifts were found to be positively related to their investment in nontraditional assets and their reliance on purchased funds. The findings indicate that promotional expenditures have increased due to the increased competition in the local markets as a result of the introduction of interstate banking during the period.

Myocardial relaxation is governed by the interplay of two macromolecular systems: (1) myofilaments and (2) calcium extruding pumps/exchangers. In myocardium from failing hearts, both systems act more slowly than normal, and cause relaxation to decelerate, which may impede early rapid filling and can often limit cardiac pumping ability--especially during exercise. Gene-based therapy to augment sluggish SERCA pumps is a possibility being currently investigated in research laboratories. In normal myocardium, the rate of dissociation of myosin crossbridges sets the rate of relaxation. In this case, relaxation is characterized by two features: (1) load-dependence and (2) displacement-dependence. Load-dependence derives from cooperative mechanisms acting among ensembles of crossbridges and myofilament regulatory proteins (troponin, tropomyosin); it allows contraction to be prolonged when more crossbridges are attached and mutually support each other. The rate of relaxation can still be rapid, however, as this cooperative system begins to collapse. Displacement-dependence is more important later in contraction, because tenuous crossbridge attachments cannot easily re-form after being disrupted when myofilaments slide along each other. Myofilaments control normal relaxation because the calcium extruding systems reduce calcium to near diastolic levels relatively early; however, when the relative timing of crossbridge dissociation versus calcium sequestration is altered, and calcium uptake is slowed (relative to crossbridges), then removal of calcium can become rate limiting instead. In this case, load- and displacement-dependence are less marked. Both the timing of calcium removal and the sensitivity of the myofilaments to calcium affect relaxation timing.