Early Dark Energy Can Resolve The Hubble Tension

Early dark energy (EDE) that behaves like a cosmological constant at early times (redshifts $z\gtrsim3000$) and then dilutes away like radiation or faster at later times can solve the Hubble tension. In these models, the sound horizon at decoupling is reduced resulting in a larger value of the Hubble parameter $H_0$ inferred from the cosmic microwave background (CMB). We consider two physical models for this EDE, one involving an oscillating scalar field and another a slowly-rolling field. We perform a detailed calculation of the evolution of perturbations in these models. A Markov Chain Monte Carlo search of the parameter space for the EDE parameters, in conjunction with the standard cosmological parameters, identifies regions in which $H_0$ inferred from {\it Planck} CMB data agrees with the SH0ES local measurement. In these cosmologies, current baryon acoustic oscillation and supernova data are described as successfully as in \LCDM, while the fit to {\it Planck} data is slightly improved. Future CMB and large-scale-structure surveys will further probe this scenario.Comment: v1: 4p+appendix, 3 figures. v2: small changes, notably estimates of bayesian evidence. matches the version published in PR

A novel REBOA system: Prototype and proof of concept

Background: Lower torso hemorrhage is a significant cause of death from injuries in combat. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been used to rescue patients successfully in the hospital setting, but its prehospital use is controversial. We designed a device that would be easy to use, safer in injured vessels, migration-resistant and amenable to a prehospital environment. Methods: We designed a novel, balloon-led device using common commercial materials. Thin latex rubber was reassembled in cylindrical conformation aligned to the shape of the aorta and invaginated into vinyl tubing. The catheter is placed into the femoral vessel, followed by expression of the balloon with CO2 inflation in a proximal direction to navigate and treat damaged pelvic vasculature, occluding the distal aorta. The system was tested on model aortas (both intact and injured cadaveric porcine aorta) with inline fluid flow and pressure monitoring to determine the maximum pressure the balloons could occlude. The device was also tested on a perfused human cadaveric model. Results: Flow was occluded with the balloon up to an average of 561.1 ± 124.3 mm Hg. It always ruptured before causing damage to the porcine aorta and was able to occlude injured iliac vessels and proceed to occlude the distal aorta. The device was effective in occluding the distal aorta of a perfused human cadaver. Conclusion: This novel, high-volume, low-pressure device can occlude the distal aorta in a simulated human aorta model, cadaveric porcine model and perfused human cadaver. It can occlude fluid flow to supraphysiologic pressures. It is easy to use, migration-resistant, able to navigate and treat injured pelvic vessels, and amenable to prehospital care

Observational study of the effects of age, diabetes mellitus, cirrhosis and chronic kidney disease on sublingual microvascular flow.

BACKGROUND: Sidestream dark field (SDF) imaging has been used to demonstrate microcirculatory abnormalities in a variety of critical illnesses. The microcirculation is also affected by advancing age and chronic comorbidities. However, the effect of these conditions on SDF microcirculatory parameters has not been well described. METHODS: SDF images were obtained from five groups of 20 participants: healthy volunteers under the age of 25, healthy volunteers over the age of 55, and clinic patients over the age of 55 with one of diabetes mellitus, cirrhosis and stage 5 chronic kidney disease. Microcirculatory parameters between the groups were then compared for significance using analysis of variance for parametric and the Kruskal-Wallis test for non-parametric data. RESULTS: Median microvascular flow index was 2.85 (interquartile range 2.75 to 3.0) for participants aged 55, 2.88 (2.75 to 3.0) for those with diabetes mellitus, 3.0 (2.83 to 3.0) for those with cirrhosis and 3.0 (2.78 to 3.0) for those with chronic kidney disease (P for difference between groups = 0.14). Similarly, there were no significant differences in the proportion of perfused vessels and perfused vessel density between the groups. CONCLUSIONS: Older age, diabetes, and chronic kidney and liver disease need not be considered confounding factors for comparison of SDF microcirculatory parameters in the critically ill

Pop-Up Library

Lane Library held a Pop-Up Library outside The Galley entrance on February 27, 2018. Books and DVDs were available to check out, and librarians provided answers to questions as well as outreach to inform the campus of library services

The activities of a selected group of high school girls with reference to clothing

Call number: LD2668 .T4 1937 S6

Vascular trauma: Does experience in the United States apply to a Canadian centre?

Trauma care has evolved similarly in the United States and Canada over the last 3 decades. Like much of modern trauma care, management of vascular trauma has been influenced by combat surgery experiences in recent wars. The American Association for the Surgery of Trauma sponsored the Prospective Observational Vascular Injury Treatment (PROOVIT) registry to document changes in the treatment of vascular trauma and determine outcomes in the US. However, differences in trauma populations and trauma systems between Canada and the US need to be considered. Here we compare the vascular trauma experience at a Canadian level I trauma centre over a 5-year period to the data in the PROOVIT registry

Injury profile suffered by targets of antipersonnel improvised explosive devices: prospective cohort study

Objective To describe pattern 1 injuries caused by the antipersonnel improvised explosive device (AP-IED) in comparison to those previously described for antipersonnel mines (APM). Design Prospective cohort study of 100 consecutive pedestrian victims of an AP-IED, with traumatic amputation without regard for gender, nationality or military status. Setting Multinational Medical Unit at Kandahar Air Field, Afghanistan. Participants One hundred consecutive patients, all male, 6–44 years old. Main outcome measures The details of injuries were recorded to describe the pattern and characterise the injuries suffered by the target of AP-IEDs. The level of amputation, the level of soft tissue injury, the fracture pattern (including pelvic fractures) as well as perineal, gluteal, genital and other injuries were recorded. Results Victims of AP-IED were more likely, compared with APM victims, to have multiple amputations (70.0% vs 10.4%; p\u3c0.001) or genital injury (26% vs 13%; p=0.007). Multiple amputations occurred in 70 patients: 5 quadruple amputations, 27 triple amputations and 38 double amputations. Pelvic fracture occurred in 21 victims, all but one of whom had multiple amputations. Severe perineal, gluteal or genital injuries were present in 46 patients. Severe soft tissue injury was universal, with injection of contaminated soil along tissue planes well above entry sites. There were 13 facial injuries, 9 skull fractures and 3 traumatic brain injuries. Eleven eye injuries were seen; none of the victims with eye injuries were wearing eye protection. The casualty fatality rate was at least 19%. The presence of more than one amputation was associated with a higher rate of pelvic fracture (28.6% vs 3.3%; p=0.005) and perineal–gluteal injury (32.6% vs 11.1%; p=0.009). Conclusion The injury pattern suffered by the target of the AP-IED is markedly worse than that of conventional APM. Pelvic binders and tourniquets should be applied at the point of injury to patients with multiple amputations or perineal injuries