FATIGUE-INDUCED SEX DIFFERENCES FOR EXPLOSIVE NEUROMUSCULAR CHARACTERISTICS OF THE PLANTAR FLEXORS

Previous research on fatigue using isometric contractions suggests that females are more fatigue resistant than males, but less is clear regarding fatigue induced by dynamic contractions. PURPOSE: To determine sex differences for explosive voluntary neuromuscular characteristics of the plantar flexors (PFs) during a dynamic fatiguing task. METHODS: Recreationally active males (n=14; 22.4±2.2 yrs) and females (n=15; 20.9±2.5 yrs) performed a fatiguing task of the PFs consisting of 60 maximal isotonic contractions at 30% of their maximal isometric strength using a dynamometer. Peak power (PP), optimal velocity (OV), and optimal torque (OT) were calculated from the first five contractions of the fatigue task and five maximal isotonic contractions performed after the fatigue task. Power was calculated as the product of angular velocity and torque and PP was recorded. In addition, velocity and torque at the moment in time PP occurred were recorded as OV and OT, respectively. Rate of electromyography rise for the medial gastrocnemius (RERMG) and soleus (RERSOL) was calculated as the linear slope of the normalized electromyography-time curve. Two-way (time ´ group) repeated measures ANOVAs were used to determine sex differences across time. RESULTS: Regardless of sex, PP (-16%; pppSOL remained unchanged for both sexes (-6%; p\u3e0.05), while RERMG was only reduced in males (-21%;p=0.001). CONCLUSION: Our data indicate that explosive contractile characteristics are diminished similarly in males and females during a dynamic fatiguing task, but it appears the muscle-specific physiological mechanisms may differ between sexes

Age-Related Reduction in High-Velocity Power and Myofiber Morphology and Composition

Power is diminished more dramatically at higher contraction velocities in older adults. It has been suggested that this may reflect age-related changes in single myofiber morphology or composition. PURPOSE: To examine power, muscle activation, and single myofiber morphology and composition between young (YM) and older (OM) males. METHODS: Power, or torque × velocity, was recorded during isokinetic knee extensions at 60°·s-1 and 180°·s-1 in healthy, untrained YM (n=15; 20.7±2.2 yrs) and OM (n=15; 71.6±3.9 yrs). The relative increase in power from 60°·s-1 to 180°·s-1 was recorded for each participant. Electromyography amplitude of the vastus lateralis (VL) was normalized to its peak from a maximal isometric contraction to calculate muscle activation. VL tissue samples were obtained from a sub-sample (YM=13; OM=11) via microbiopsy and immunofluorescence was used to identify type I and IIa myofibers for subsequent analysis of cross-sectional area (CSA). Independent samples t-tests were used to compare groups and select correlations were assessed. RESULTS: Relative increase in power was greater in YM (159% vs. 115%; p=0.005). Muscle activation was similar between groups (p\u3e0.05). Individual fiber type compositions and CSA were similar between groups (p\u3e0.05), but type IIa:type I myofiber size ratio was lower in OM (-31.15%; p=0.002). Myofiber size nor composition data correlated with the relative power increase (p\u3e0.05). CONCLUSION: OM had smaller type IIa myofibers relative to type I myofiber size, which may reflect age-related motor unit remodeling. Nevertheless, and albeit a smaller sample size, myofiber size nor composition were associated with the age-related diminishment in relative power increase

The Return of a Judicial Artifact?: How the Supreme Court Could Examine the Question of the Nondelegation Doctrine’s Place in Future Cases

Undergraduate Textual or Investigativ

Query Resolution for Conversational Search with Limited Supervision

In this work we focus on multi-turn passage retrieval as a crucial component of conversational search. One of the key challenges in multi-turn passage retrieval comes from the fact that the current turn query is often underspecified due to zero anaphora, topic change, or topic return. Context from the conversational history can be used to arrive at a better expression of the current turn query, defined as the task of query resolution. In this paper, we model the query resolution task as a binary term classification problem: for each term appearing in the previous turns of the conversation decide whether to add it to the current turn query or not. We propose QuReTeC (Query Resolution by Term Classification), a neural query resolution model based on bidirectional transformers. We propose a distant supervision method to automatically generate training data by using query-passage relevance labels. Such labels are often readily available in a collection either as human annotations or inferred from user interactions. We show that QuReTeC outperforms state-of-the-art models, and furthermore, that our distant supervision method can be used to substantially reduce the amount of human-curated data required to train QuReTeC. We incorporate QuReTeC in a multi-turn, multi-stage passage retrieval architecture and demonstrate its effectiveness on the TREC CAsT dataset.Comment: SIGIR 2020 full conference pape

Taking on the network: Making space for the identity play of networked publics

This thesis is positioned in the field of communication design research and seeks to critically examine the practice and potential of identity play by digitally networked publics. It defines identity play as entailing a form of identity design practiced by participating publics themselves. The research contributes an understanding of the role of the designer in the entangled networks of digital public space by treating identity design agencies as co-produced with audiences and materials. The thesis locates identity play as part of a productive tradition of anonymous pseudonymity practices. It challenges design assumptions of anonymity as a contemporary privacy problem and of identity as detached and preexisting. The thesis elucidates an intra-active interpretation of identity design as on-going processes of collectively re-making network apparatuses and identity phenomena, moving beyond the limits of centralising and commercial models. It constructs the designer-researcher's role in making space for identity play through taking on the network. The Creative Exchange (CX) – a UK Arts & Humanities Research Council Knowledge Exchange Hub – provided the space to collaborate and research with diverse consortia of designer-researcher participants and their networked audiences to explore the possibilities of digital public space. The methodology employed by the thesis is grounded theory research through design underpinned by a "diffractive" research stance, with theory and practice read iteratively through each other. I have collected and critically analysed data using "design conversations" with materials, participants and audiences, through multiple projects and prototypes, bounded by the CX Hub and its activities over five years. The thesis constructs three prototype design patterns to make space for the identity play of networked publics from my practice as a designer-researcher: Sticking together, Fashioning our own belongings and Taking on the network. Each pattern produces an intersection of practices of identity design, networked public participation and design research. The design pattern of Sticking together offers ways of using assemblage to create anonymity and reputation. It calls for and requires the solidarity of collective assembly and ways to make identity play commonplace. Fashioning our own belongings investigates possessions as embodied networked apparatuses of identity, and audience relations as belonging. This design pattern grasps network function and fosters pseudonymity (dis)ownership. Taking on the network is formulated as a performance of inversion by publics through the resistance of the carnivalesque and the responsibility of infrastructural inversions. Taking on the network provides the overarching framework for the design patterns to take on the functions and models of cloud infrastructures. These findings demonstrate how identity design by publics requires active forms of network literacy that comprehend the network intra-actively, and that it is possible to take on the network by contesting cloud identity apparatuses and models. The design patterns make space for the identity play that, importantly, enables critical and creative anonymity practices to take place. The research offers identity play as a public critical infrastructure with benefits for the resilience and creativity of networked publics. It lends support to designers to reconfigure their part in identity design. The original contributions to knowledge are: (1) prototype design patterns for making space for the identity play of networked publics; (2) an articulation of the design space for identity play; (3) a diffractive form of design pattern that entails multiple intersecting practices; and (4) an intra-active interpretation of the discipline of identity design

Pathways to Credentials: Does the Timing of Earning an Industry Certification in High School Influence Postsecondary Educational Outcomes?

Earning industry certifications helps people prepare for jobs in a range of careers. Doing so in secondary school may help students prepare for college as well. Using administrative data on two cohorts of first-time 9th graders in Florida, we examined whether earning a certification was associated with postsecondary enrollment and degree attainment and whether the timing of the certification influenced that relationship. Earning a certification in high school prepared students for success in both 2-year and 4-year colleges. However, the patterns of certifications and college enrollment and degree attainment differed based on when students earned the certification. For early earners the certification was more closely associated with enrollment and attainment at 4-year colleges; for later earners, the certification was closely associated with enrollment and attainment in 2-year colleges

Late High School Dropouts characteristics, experiences, and changes across cohorts : descriptive analysis report /

Titre de l'écran-titre (visionné le 15 juin 2009)

Gibt es einen wissenschaftlichen Konsens zur Wirtschaftlichkeit nachhaltiger Immobilien?

ZusammenfassungEs besteht ein klarer wissenschaftlicher und gesellschaftlicher Konsens über die Schlüsselrolle, die Gebäuden und der gebauten Umwelt bei der Reduzierung von Treibhausgasemissionen und Ressourcenverbrauch zukommt. Unklar ist jedoch, inwieweit Umweltziele und ökonomische Rentabilität im Immobilienbereich miteinander einhergehen. Dieser Artikel analysiert 42 internationale Studien zur Rentabilitaet von Immobilien mit Nachhaltigkeitszertifikaten anhand einer Metaanalyse und kommt zu dem Schluss, dass diese Gebäude zumindest ein moderater Preis- und Mietpraemium erzielen. Obwohl es Hinweise darauf gibt, dass Studien, die positive Ergebnisse berichten, mit höherer Wahrscheinlichkeit veröffentlicht wurden, liefern diese Studien dennoch einen Anhhaltspunkt dafür, dass nachhaltiges Bauen und Sanieren vom Markt als wirtschaftlich sinnvoll erkannt und entsprechend bepreist wird. Dabei ist allerdings zu bedenken, dass der wirtschaftliche Erfolg umweltgerechter Immobilieninvestments unter anderem auch davon abhängt, inwieweit Marktmechanismen etabliert werden können, die ein effiziente Verteilung von Risiko und Rendite ermöglichen, wie zum Beispiel grüne Mietverträge oder Energiespar-Contracting.</jats:p

Parler and the Road to the Capitol Attack: Investigating Alt-Tech Ties to January 6

The January 6, 2021 mob assault on the U.S. Capitol exposed deep fissures between Americans and shook the very foundations of the country. The violence that day and the tech industry's response to the tsunami of polarizing content triggered a major public debate over how social media and tech companies manage their platforms and services and the impact of content moderation policies on polarization, extremism, and political violence in the United States. That debate is also now playing out in Congress where the House Select Committee to Investigate the January 6th Attack on the United States Capitol is now underway. One big question is: How did niche social media sites geared toward far-right audiences, like Parler, contribute to polarization around the 2020 presidential election and to what extent did Parler and other platforms factor into the January 6 attack? The first in a series of investigations into the impact of the alt-tech movement on U.S. national security, this report provides an initial snapshot of observations culled from an ongoing analysis of open source data related to the Capitol attack.Based, in part, on an early assessment of a cache of an estimated 183 million Parler posts publicly archived after Parler was temporarily deplatformed, the analysis in this report offers unique insights into online and offline early warning signs of the potential for election-related violence in the year-long run up to the Capitol attack. On the streets and online, the networked effects of poor platform governance across the internet during the 2020 presidential election were notable on mainstream and fringe social media sites. Nevertheless, the combined impact of Parler's loose content moderation scheme as well as data-management practices and platform features—either by design or neglect, or both—may have made the social media startup especially vulnerable to strategic influence campaigns that relied heavily on inauthentic behavior like automated content amplification and deceptive techniques like astroturfing

Noncognitive skills in the classroom

This book provides an overview of recent research on the relationship between noncognitive attributes (motivation, self efficacy, resilience) and academic outcomes (such as grades or test scores). We focus primarily on how these sets of attributes are measured and how they relate to important academic outcomes. Noncognitive attributes are those academically and occupationally relevant skills and traits that are not “cognitive”—that is, not specifically intellectual or analytical in nature. We examine seven attributes in depth and critique the measurement approaches used by researchers and talk about how they can be improved.Publishe