Galactic cosmic ray exposure estimates for SAGE-3 mission in polar orbit

An analysis of the effects of galactic cosmic ray (GCR) exposures on charge-coupled devices (CCDs) was performed for the SAGE-III 5-year mission in sun-synchronous orbit between 1996 and 2001. A detailed environment model used in conjunction with a geomagnetic vertical cut-off code provides the predicted 5-year fluence of GCR ions. A computerized solid model of the spacecraft was used to define the effective shield thickness distribution around the CCD detector. The particle fluences at the detector location are calculated with the Langley heavy-ion transport code, and these fluences are used in conjunction with estimated nuclear stopping powers to evaluate dosimetric quantities related to the detector degradation. A previous study analyzing effects of trapped particle and solar flare protons indicated an approximate 20 percent reduction in detector sensitivity for the mission. The galactic cosmic ray contribution was thought to be relatively small and therefore was not previously analyzed. The present study provides quantification of the GCR effects, which are found to contribute less than 1 percent of the total environment degradation

What are the benefits of treating sleep apnea?

There is little benefit to treating patients with sleep apnea who do not have daytime sleepiness. For patients with symptoms, treating those with moderate to severe sleep apnea is more reliably associated with benefits than treating those with a mild case. Benefits include: decreased daytime sleepiness; improvements in subjective sleep quality in patient and sleep partner; improved psychologic well-being, cognitive function, and quality of life; decreased numbers of traffic accidents; and small decreases in blood pressure. (Grade of recommendation: B-, based primarily on cohort studies and case series and a small number of randomized controlled trials [RCTs]

Synthetic biodegradable polymers as orthopedic devices,"

Abstract Polymer scientists, working closely with those in the device and medical "elds, have made tremendous advances over the past 30 years in the use of synthetic materials in the body. In this article we will focus on properties of biodegradable polymers which make them ideally suited for orthopedic applications where a permanent implant is not desired. The materials with the greatest history of use are the poly(lactides) and poly(glycolides), and these will be covered in speci"c detail. The chemistry of the polymers, including synthesis and degradation, the tailoring of properties by proper synthetic controls such as copolymer composition, special requirements for processing and handling, and mechanisms of biodegradation will be covered. An overview of biocompatibility and approved devices of particular interest in orthopedics are also covered

Use of Monofilament Line, Reflective Tape, Beach-Balls, and Pyrotechnics for Controlling Grackle Damage to Citrus

The effectiveness of monofilament line, reflective tape, beach-balls and pyrotechnics (propane cannons and shotgun scare shells) in reducing damage to citrus by great-tailed grackles was tested in the lower Rio Grande Valley of southern Texas. Results indicate that these treatments can produce reduction in damage. Whether the treatments are economically advisable for a grower depends on the history of grackle damage to the grove and grove size. Only large amounts of damage in large groves justify costs associated with implementation of these methods

Use of Monofilament Line, Reflective Tape, Beach-Balls, and Pyrotechnics for Controlling Grackle Damage to Citrus

The effectiveness of monofilament line, reflective tape, beach-balls and pyrotechnics (propane cannons and shotgun scare shells) in reducing damage to citrus by great-tailed grackles was tested in the lower Rio Grande Valley of southern Texas. Results indicate that these treatments can produce reduction in damage. Whether the treatments are economically advisable for a grower depends on the history of grackle damage to the grove and grove size. Only large amounts of damage in large groves justify costs associated with implementation of these methods

The effects of 10 days of separate heat and hypoxic exposure on heat acclimation and temperate exercise performance

Adaptations to heat and hypoxia are typically studied in isolation but are often encountered in combination. Whether the adaptive response to multiple stressors affords the same response as when examined in isolation is unclear. We examined 1) the influence of overnight moderate normobaric hypoxia on the time course and magnitude of adaptation to daily heat exposure and 2) whether heat acclimation (HA) was ergogenic and whether this was influenced by an additional hypoxic stimulus. Eight males [V̇o2max = 58.5 (8.3) ml·kg-1·min-1] undertook two 11-day HA programs (balanced-crossover design), once with overnight normobaric hypoxia (HAHyp): 8 (1) h per night for 10 nights [[Formula: see text] = 0.156; SpO2 = 91 (2)%] and once without (HACon). Days 1, 6, and 11 were exercise-heat stress tests [HST (40°C, 50% relative humidity, RH)]; days 2-5 and 7-10 were isothermal strain [target rectal temperature (Tre) ~38.5°C], exercise-heat sessions. A graded exercise test and 30-min cycle trial were undertaken pre-, post-, and 14 days after HA in temperate normoxia (22°C, 55% RH; FIO2 = 0.209). HA was evident on day 6 (e.g., reduced Tre, mean skin temperature (T̄sk), heart rate, and sweat [Na+], P < 0.05) with additional adaptations on day 11 (further reduced T̄sk and heart rate). HA increased plasma volume [+5.9 (7.3)%] and erythropoietin concentration [+1.8 (2.4) mIU/ml]; total hemoglobin mass was unchanged. Peak power output [+12 (20) W], lactate threshold [+15 (18) W] and work done [+12 (20) kJ] increased following HA. The additional hypoxic stressor did not affect these adaptations. In conclusion, a separate moderate overnight normobaric hypoxic stimulus does not affect the time course or magnitude of HA. Performance may be improved in temperate normoxia following HA, but this is unaffected by an additional hypoxic stressor

Editorial:Cross adaptation and cross tolerance in human health and disease

Human physiological responses to heat, cold, hypoxia, microgravity, hyperbaria, hypobaria and fasting are well studied in isolation. However, in the natural world these stressors are often combined or experienced sequentially (Tipton, 2012). Studies examining human responses to these more realistic, yet relatively complex, circumstances remain sparse, but could provide important insights into an emerging area within human physiology: cross-adaptation (Figure 1)(Lunt et al., 2010; Gibson et al., 2017). Much of the current state of knowledge involves data demonstrating benefits of exercising in hot conditions, prior to performance in hypoxia (Gibson et al., 2015; Heled et al., 2012; Lee et al., 2014a, 2014b, 2016; Salgado et al., 2017; White et al., 2016), with cold to hypoxia (Lunt et al., 2010), hypoxia to heat (Sotiridis et al., 2018), combined stressors (Neal et al., 2017; Takeno et al., 2001), and more mechanistic (signalling) data from animal models exposed to substantive volumes of stress (Maloyan & Horowitz, 2002, 2005). The role of nutrient availability and the nutrient-exercise interactions which drive phenotypic adaptations to skeletal muscle exposed to a multitude of stressors is also a growing field of interest (Hawley, Lundby, Cotter, & Burke, 2018). This research topic includes publications which address both clinical and exercise-centric aspects allied to Cross-adaptation and Cross-tolerance in Human Health and Disease