Bicycle helmet ventilation and comfort angle dependence

Five modern bicycle helmets were studied to elucidate some of the variations in ventilation performance, using both a heated manikin headform and human subjects (n=7). Wind speed and head angle were varied to test their influence on the measured steady-state heat exchange (cooling power) in the skull section of the headform. The cooling power transmitted by the helmets varied from about 60% to over 90% of that of the nude headform, illustrating the range of present manufacturer designs. Angling the head forward by 30° was found to provide better cooling power to the skull (up to 25%) for three of the helmets and almost equal cooling power in the remaining two cases. Comparisons of skull ventilation at these angles with human subjects strongly supported the headform result

Justice for sale: the rhetoric of for profit probation and rehabilitation

This work analyzes the rhetoric of for-profit probation and rehabilitation companies in the United States. In particular, this study examines how dichotomies have shifted our social understanding of the word “criminal” and created an environment where a justice system mediated by money can thrive. This study uses Kenneth Burke’s theories of identification and division, Ann E. Berthoff’s theories of dichotomies and dialectic, and Michel Foucault’s theories of power relations and ceremonies of punishment, and focuses on Paulo Freire’s practice of world building and James Porter et al’s practice of institutional critique to find points of intervention that are available to rhetoric and composition scholars. Chapter One argues that Reagan’s revival of the war on drugs reframed addicts as criminals in need of incarceration rather than persons in need of help. That rhetoric created a dialectic framework that made dichotomous points out of criminals and the rest of America. Chapter Two analyzes for-profit probation and rehabilitation companies as rhetorical constructs and examines how rhetorical agency is formed and articulated within those constructs. Further, Chapter Two offers insights from interviews to analyze how communication practices shape what it means to be a criminal in the United States and how they shape what is acceptable in punishing criminals. Interviews from participants that have been through both for-profit probation and rehabilitation companies, as well as document analysis of house bills, and rhetorical analysis of the ways for-profit companies market themselves to communities and potential employers are utilized to illustrate the gaps and fissures between how companies represent themselves and what their practices are. This study offers a reflection on and analysis of the communication practices of for-profit probation and rehabilitation companies, and is a stepping-stone to the active practice of institutional critique and world building

Radial Velocity Observations and Light Curve Noise Modeling Confirm That Kepler-91b is a Giant Planet Orbiting a Giant Star

Kepler-91b is a rare example of a transiting hot Jupiter around a red giant star, providing the possibility to study the formation and composition of hot Jupiters under different conditions compared to main-sequence stars. However, the planetary nature of Kepler-91b, which was confirmed using phase-curve variations by Lillo-Box et al., was recently called into question based on a re-analysis of Kepler data. We have obtained ground-based radial velocity observations from the Hobby-Eberly Telescope and unambiguously confirm the planetary nature of Kepler-91b by simultaneously modeling the Kepler and radial velocity data. The star exhibits temporally correlated noise due to stellar granulation which we model as a Gaussian Process. We hypothesize that it is this noise component that led previous studies to suspect Kepler-91b to be a false positive. Our work confirms the conclusions presented by Lillo-Box et al. that Kepler-91b is a 0.73+/-0.13 Mjup planet orbiting a red giant star.Comment: Published in Ap

Transpulmonary thermodilution using femoral indicator injection: a prospective trial in patients with a femoral and a jugular central venous catheter

INTRODUCTION: Advanced hemodynamic monitoring using transpulmonary thermodilution (TPTD) is established for measurement of cardiac index (CI), global end-diastolic volume index (GEDVI) and extra-vascular lung water index (EVLWI). TPTD requires indicator injection via a central venous catheter (usually placed via the jugular or subclavian vein). However, superior vena cava access is often not feasible due to the clinical situation. This study investigates the conformity of TPTD using femoral access. METHODS: This prospective study involved an 18-month trial at a medical intensive care unit at a university hospital. Twenty-four patients with both a superior and an inferior vena cava catheter at the same time were enrolled in the study. RESULTS: TPTD-variables were calculated from TPTD curves after injection of the indicator bolus via jugular access (TPTDjug) and femoral access (TPTDfem). GEDVIfem and GEDVIjug were significantly correlated (rm = 0.88; P < 0.001), but significantly different (1,034 +/- 275 vs. 793 +/- 180 mL/m2; P < 0.001). Bland-Altman analysis demonstrated a bias of +241 mL/m2 (limits of agreement: -9 and +491 mL/m2). GEDVIfem, CIfem and ideal body weight were independently associated with the bias (GEDVIfem-GEDVIjug). A correction formula of GEDVIjug after femoral TPTD, was calculated. EVLWIfem and EVLWIjug were significantly correlated (rm = 0.93; P < 0.001). Bland-Altman analysis revealed a bias of +0.83 mL/kg (limits of agreement: -2.61 and +4.28 mL/kg). Furthermore, CIfem and CIjug were significantly correlated (rm = 0.95; P < 0.001). Bland-Altman analysis demonstrated a bias of +0.29 L/min/m2 (limits of agreement -0.40 and +0.97 L/min/m2; percentage-error 16%). CONCLUSIONS: TPTD after femoral injection of the thermo-bolus provides precise data on GEDVI with a high correlation, but a self-evident significant bias related to the augmented TPTD-volume. After correction of GEDVIfem using a correction formula, GEDVIfem shows high predictive capabilities for GEDVIjug. Regarding CI and EVLWI, accurate TPTD-data is obtained using femoral access

Systemic Capillary Leak Syndrome associated with hypovolemic shock and compartment syndrome. Use of transpulmonary thermodilution technique for volume management

Systemic Capillary Leak Syndrome (SCLS) is a rare disorder characterized by increased capillary hyperpermeability leading to hypovolemic shock due to a markedly increased shift of fluid and protein from the intravascular to the interstitial space. Hemoconcentration, hypoalbuminemia and a monoclonal gammopathy are characteristic laboratory findings. Here we present a patient who suffered from SCLS with hypovolemic shock and compartment syndrome of both lower legs and thighs. Volume and catecholamine management was guided using transpulmonary thermodilution. Extended hemodynamic monitoring for volume and catecholamine management as well as monitoring of muscle compartment pressure is of crucial importance in SCLS patients