Variance in heat tolerance in bumble bees correlates with species geographic range and is associated with several environmental and biological factors.

Globally, insects have been impacted by climate change, with bumble bees in particular showing range shifts and declining species diversity with global warming. This suggests heat tolerance is a likely factor limiting the distribution and success of these bees. Studies have shown high intraspecific variance in bumble bee thermal tolerance, suggesting biological and environmental factors may be impacting heat resilience.

Physiological consequences of U.S. Army Ranger training.

Purpose: Soldiers are expected to maintain a high degree of physical readiness as operational demands can severely degrade performance capabilities. This study examined the physiological consequences of U.S.

Novel nutritional immune formula maintains host defense mechanisms.

Military combat and training stress induce immune changes that increase the risk of infection and ultimately influence soldiers' performance and readiness. Strenuous military training/assessment provides a uniform stress and the opportunity to evaluate nutritional strategies to minimize stress-induced immune changes that predispose soldiers to infection. Immunological changes and effects of a novel nutritional immune formula (NNIF) were examined prospectively in a double-blind, controlled study of 200 soldiers attending Special Forces Assessment and Selection School.

Detection times and analytical performance of commercial urine opiate immunoassays following heroin administration.

The Federal Workplace Drug Testing Program changed urine screening and confirmation cutoff concentrations for opiate testing from 300 to 2000 ng/mL in 1998. Morphine was the designated target compound. An additional heroin metabolite, 6-acetylmorphine (6-AM), was added to the testing procedure with a cutoff concentration > or = 10 ng/mL.

Retrospective study of urinalysis for dl-amphetamine and dl-methamphetamine analysis under current Department of Defense guidelines.

Under current Department of Defense (DOD) directive, the laboratories certified to conduct urinalyis testing in support of the DOD Drug Deterrence Program are required to conduct dl-isomer analysis on all specimens that confirm at a concentration greater than 500 ng/mL methamphetamine (METH). Although the same cutoff concentration is required for amphetamine (AMP) reporting, there is no requirement for dl-isomer analysis of AMP-positive specimens. Of the 894,823 specimens screened by the Army Drug Testing Laboratory at Ft.

Exertional fatigue, sleep loss, and negative energy balance increase susceptibility to hypothermia.

The purpose of this study was to determine how chronic exertional fatigue and sleep deprivation coupled with negative energy balance affect thermoregulation during cold exposure. Eight men wearing only shorts and socks sat quietly during 4-h cold air exposure (10 degreesC) immediately after (<2 h, A) they completed 61 days of strenuous military training (energy expenditure approximately 4,150 kcal/day, energy intake approximately 3,300 kcal/day, sleep approximately 4 h/day) and again after short (48 h, SR) and long (109 days, LR) recovery. Body weight decreased 7.

Physical performance and metabolic recovery among lean, healthy men following a prolonged energy deficit.

Previous studies have demonstrated that full recovery from weight loss may take months or years. The present investigation examined short-term recovery (5 wks "post") of physical performance (muscular strength, muscular power, vertical jump), body composition, metabolic hormones (testosterone, luteinizing hormone, sex hormone binding globulin, insulin-like growth factor-1, triiodothyronine, thyroxine, thyroid binding globulin, and thyroid-stimulating hormone) and metabolic markers (transferrin, ferritin, prealbumin, glycerol, nonesterified fatty acids, high-density lipoproteins, and lactate) in 10 healthy young men after an 8-week Army course with an energy deficit (1000 kcal/d) and loss of body mass (-12%). Subjects ate ad libitum after the course ended ("post").

Carbohydrate-electrolyte solution effects on physical performance of military tasks.

Background: Physical performance of military tasks can deteriorate during field training.

Hypothesis: Drinking a carbohydrate-electrolyte (CHO-E) beverage during military relevant training would improve fluid and caloric intake, and better sustain physical performance.

Methods: Some 27 volunteers restricted to approximately 2600 kcal.

Effects of food restriction in military training on T-lymphocyte responses.

In a stress model which included food restriction, we examined the effects of physically rigorous military training and increased caloric intake on T-lymphocyte responses and lymphocyte subsets. T-lymphocyte proliferation and release of soluble receptor for interleukin-2 (slL-2R) in vitro were measured in two separate training classes of male U.S.

Use of bioelectrical impedance analysis measurements as predictors of physical performance.

Through its association with fat-free mass (FFM), bioelectrical impedance analysis (BIA) offers an alternative to physical performance testing. We examined the relations between stature2/resistance (S2/R), FFM, and muscular strength in data from three studies of young military men and women. Resistance was measured at 50 kHz by using the conventional tetrapolar electrode method.

Regional fat placement in physically fit males and changes with weight loss.

The abdomen is the principal site of fat deposition in men, and because abdominal fat is readily mobilized during exercise, the relative proportion of fat in the abdominal site may negatively correlate with the amount of regular physical activity, and even with physical fitness. This study presents data for regional fatness in 165 fit young men (U.S.

Kinetics of nitrogen oxide production following experimental thermal injury in rats.

Nitric oxide is biosynthesized from the amino acid L-arginine by the enzyme nitric oxide synthase. Nitric oxide is a vasodilator, a neurotransmitter, and may modulate immune function. The experiments presented here were performed to determine whether the synthesis of nitric oxide is increased following experimental burn injury in rats.

A rabbit model of inhalation injury.

In the course of developing a model of inhalation injury, the relationship between the severity of pulmonary injury and specific techniques and doses of smoke exposure was examined in pairs of rabbits simultaneously exposed to smoke. In group I (5 pairs), one animal in each pair was exposed to smoke with a breath hold (BH) at the end of each exposure; the second animal received an exposure producing the same level of carboxyhemoglobin without BH. In group II (6 pairs), both animals were exposed to 25 units of smoke simultaneously, with BH.

Simultaneous determination of lactulose and mannitol in urine of burn patients by gas-liquid chromatography.

Ratios of lactulose/mannitol excretion in urine have been used to assess the extent of intestinal permeability in various disease and trauma conditions. Reported studies have used this technique to correlate altered gastrointestinal mucosal permeability to translocation of bacteria and endotoxin, leading to occult sepsis in burn patients. Enzymatic methods of analysis for urine concentrations of mannitol and lactulose were used in these studies.

The interaction of burn injury and zinc nutriture as assessed by the humoral response to sheep red blood cells in a burn rat model.

Clinical and animal studies suggest that burn injury induces alterations in zinc metabolism. It also has been established that zinc nutriture can cause alterations in the immune response, but there is a paucity of information concerning the interrelationship between burn injury, zinc nutriture and the immune response. In the present study, rats were subjected to full skin thickness dorsal scald injuries covering 30 per cent of the total body surface and then maintained on sufficient or deficient zinc intake.

Alterations in intestinal permeability after thermal injury.

Alterations in intestinal permeability have been postulated to occur after thermal injury. We evaluated the status of intestinal permeability during the first 2 postburn weeks in 15 subjects by measuring the differential excretion of enterally administered lactulose and mannitol. The mean age and burn size of the patients were 32.

Investigation of the validity of postural evaluation skills in assessing lumbar lordosis using photographs of clothed subjects.

Data for this study was collected at the 1988 Texas Physical Therapy Association Annual Conference with approval through the state Research Committee. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Army, the Department of Defense, or the US. Government.

Electrophysiologic responses of human sural nerve to temperature.

The purpose of this study was to assess the conduction, specifically the latency and amplitude of the sensory nerve action potential (SNAP), of the sural nerve as a function of intraneural temperature of the leg. The electrophysiologic responses of the sural nerve were determined at different temperatures in 22 healthy adults. Distal sensory latency and amplitude of the sural SNAP was determined at 1 degree C intervals over a limb temperature range of 23 degrees to 40 degrees C.

A comparison of actual and apparent lumbar lordosis in black and white adult females.

The purposes of this study were to investigate differences in lumbar lordosis in black and white adult females and to explain the clinical impression that blacks have a greater lordosis than whites. An actual lumbosacral lordosis angle (ALS) was measured from a standing right lateral lumbosacral radiograph using the angle formed from the intersection of lines drawn across the top of the second lumbar vertebral body (L2) and across the top of the sacrum. An actual lumbo-lumbar angle (ALL) was measured in the same manner, except the second line was drawn across the bottom of the fifth vertebral body (L5).

Investigation of the flexible ruler as a noninvasive measure of lumbar lordosis in black and white adult female sample populations.

The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Army, the Department of Defense, or the U.S. Government.

The effect of burn injury and zinc nutriture on fecal endogenous zinc, tissue zinc distribution, and T-lymphocyte subset distribution using a murine model.

The interrelationship among burn injury, zinc metabolism, and circulating T-lymphocyte distribution was studied using a rat model. Sixty Sprague-Dawley male rats were fed a zinc-deficient (less than 0.5 ppm) semipurified diet and given daily subcutaneous injections of 1 mg Zn/kg body wt for 14 days.

Trace mineral supplementation of burn patients: a national survey.

Much research effort has been devoted to determination of caloric and protein requirements in burn patients. Although it is generally accepted that trace mineral requirements increase concomitantly with caloric and protein needs, little research has been conducted to document that assumption. Our survey was undertaken to assess current practice and identify research needs.

Cadmium-induced suppression of the primary immune response and acute toxicity in mice: differential interaction of zinc.

Four groups of 6-week-old C3H mice were injected sc with either sterile saline, 2.8 mg Cd/kg body weight, 2.8 mg Zn/kg body weight, or 2.