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1.
Mov Ecol ; 8: 39, 2020.
Article in English | MEDLINE | ID: mdl-33072330

ABSTRACT

BACKGROUND: Temperatures in arctic-boreal regions are increasing rapidly and pose significant challenges to moose (Alces alces), a heat-sensitive large-bodied mammal. Moose act as ecosystem engineers, by regulating forest carbon and structure, below ground nitrogen cycling processes, and predator-prey dynamics. Previous studies showed that during hotter periods, moose displayed stronger selection for wetland habitats, taller and denser forest canopies, and minimized exposure to solar radiation. However, previous studies regarding moose behavioral thermoregulation occurred in Europe or southern moose range in North America. Understanding whether ambient temperature elicits a behavioral response in high-northern latitude moose populations in North America may be increasingly important as these arctic-boreal systems have been warming at a rate two to three times the global mean. METHODS: We assessed how Alaska moose habitat selection changed as a function of ambient temperature using a step-selection function approach to identify habitat features important for behavioral thermoregulation in summer (June-August). We used Global Positioning System telemetry locations from four populations of Alaska moose (n = 169) from 2008 to 2016. We assessed model fit using the quasi-likelihood under independence criterion and conduction a leave-one-out cross validation. RESULTS: Both male and female moose in all populations increasingly, and nonlinearly, selected for denser canopy cover as ambient temperature increased during summer, where initial increases in the conditional probability of selection were initially sharper then leveled out as canopy density increased above ~ 50%. However, the magnitude of selection response varied by population and sex. In two of the three populations containing both sexes, females demonstrated a stronger selection response for denser canopy at higher temperatures than males. We also observed a stronger selection response in the most southerly and northerly populations compared to populations in the west and central Alaska. CONCLUSIONS: The impacts of climate change in arctic-boreal regions increase landscape heterogeneity through processes such as increased wildfire intensity and annual area burned, which may significantly alter the thermal environment available to an animal. Understanding habitat selection related to behavioral thermoregulation is a first step toward identifying areas capable of providing thermal relief for moose and other species impacted by climate change in arctic-boreal regions.

2.
Sports (Basel) ; 8(7)2020 Jul 17.
Article in English | MEDLINE | ID: mdl-32708930

ABSTRACT

Prior evidence demonstrates the efficacy by which plyometric activities during warm-up conditions augment the subsequent performance in power-centric exercise. We investigated the acute effects of loaded jump squats incorporated into a standard sprinters' warm-up protocol on subsequent sprint performance in collegiate track athletes. Sprint times of 22 male and female collegiate track athletes were measured in 10-m intervals during a 30-m sprint trial following a standard sprinters' warm-up routine with or without plyometric exercise. Subjects were tested on two separate occasions, once with loaded jump squats as the experimental treatment (two sets of eight jumps, load = 13% bodyweight) (PLYO) and once with time-equated rest as the control treatment (CON). Treatments were implemented following a standard sprinters' warm-up routine familiar to the subjects. A dependent T-test was used for comparison of sprint interval times between conditions with a significant effect indicated by a p-value < 0.05. Sprint time did not differ between CON vs. PLYO at the 10 m (PLYO = 1.90 ± 0.12 s vs. CON = 1.90 ± 0.11 s, p = 0.66), 20 m (PLYO = 3.16 ± 0.21 s vs. CON = 3.15 ± 0.19 s, p = 0.53), and 30 m (PLYO = 4.32 ± 0.32 s vs. CON = 4.31 ± 0.28 s, p = 0.61) intervals. There was no interaction between treatment and sex, sex-specific ranking (above vs. below sex-specific mean), or sprint event (short vs. short-long vs. long) for 10 m, 20 m, or 30-m interval sprint times. At least within the limits of the current investigation, no evidence was provided to suggest that jump squats loaded at 13% bodyweight are an effective means to acutely potentiate sprint performance in collegiate track athletes. However, a further examination of responders indicates that the present loaded jump squat protocol may preferentially potentiate sprint performance in faster male athletes.

3.
J Wildl Dis ; 48(4): 1088-91, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23060515

ABSTRACT

Free-ranging Alaskan moose calves (Alces alces gigas) were immobilized with 0.12 mg/kg sufentanil (S; n=16), 0.12 mg/kg sufentanil plus 0.27 mg/kg xylazine (SX; n=11), or 0.007 mg/kg carfentanil plus 0.36 mg/kg xylazine (CX; n=13). Immobilants were antagonized with 1.2 mg/kg naltrexone (S) or 1.2 mg/kg naltrexone plus 2.4 mg/kg tolazoline (SX, CX). There were no differences in induction (P ≥ 0.29) or processing (P ≥ 0.44) times between groups. Moose given either S or SX had significantly shorter recovery times than moose given CX (P=0.001) and recovery times from S were shorter than from SX (P=0.02). Oxygen saturation values for all groups averaged 85 ± 8%, but were significantly higher (P=0.048) for CX (89 ± 7%) than for S (82 ± 8%). Based on these data, sufentanil at 0.1 mg/kg or sufentanil at 0.1 mg/kg plus xylazine at 0.25 mg/kg could provide effective remote immobilization for Alaskan moose calves and could be substituted for carfentanil or thiafentanil should the need arise.


Subject(s)
Deer/physiology , Immobilization/veterinary , Narcotics/pharmacology , Sufentanil/pharmacology , Alaska , Anesthesia Recovery Period , Animals , Animals, Newborn , Animals, Wild , Dose-Response Relationship, Drug , Female , Fentanyl/analogs & derivatives , Fentanyl/pharmacology , Immobilization/methods , Male , Naltrexone/administration & dosage , Oxygen/blood , Respiration/drug effects , Time Factors , Tolazoline/administration & dosage , Xylazine/pharmacology
4.
Kidney Int ; 59(6): 2273-81, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11380831

ABSTRACT

BACKGROUND: High protein intake is an accepted risk factor for renal stone disease. Whether meat protein intake affects oxaluria, however, remains controversial in healthy subjects and in stone formers. This study was designed (1) to test the oxaluric response to a meat protein load in male recurrent idiopathic calcium stone formers (ICSFs) with and without mild metabolic hyperoxaluria (MMH and non-MMH, respectively), as well as in healthy controls, and (2) to seek for possible disturbed vitamin B(6) metabolism in MMH, in analogy with primary hyperoxaluria. METHODS: Twelve MMH, 8 non-MMH, and 13 healthy males were studied after five days on a high meat protein diet (HPD; 700 g meat/fish daily) following a run-in phase of five days on a moderate protein diet (MPD; 160 g meat/fish daily). In both diets, oxalate-rich nutrients were avoided, as well as sweeteners and vitamin C-containing medicines. Twenty-four-hour urinary excretion of oxalate was measured on the last day of each period, along with 4-pyridoxic acid (U(4PA)) and markers of protein intake, that is, urea, phosphate, uric acid, and sulfate. Serum pyridoxal 5' phosphate (S(P5P)) was measured after protein loading. RESULTS: Switching from MPD (0.97 +/- 0.18 g protein/kg/day) to HPD (2.26 +/- 0.38 g protein/kg/day) led to the expected rise in the urinary excretion rates of all markers of protein intake in all subjects. Concurrently, the mean urinary excretion of oxalate increased in ICSFs taken as a whole (+73 +/- 134 micromol/24 h, P = 0.024) as well as in the MMH subgroup (+100 +/- 144 micromol/24 h, P = 0.034) but not in controls (-17 +/- 63 micromol/24 h). In seven ICSFs (4 MMH and 3 non-MMH) but in none of the healthy controls (P = 0.016, chi square), an increment in oxaluria was observed and considered as significant based on the intra-assay coefficient of variation at our laboratory (8.5%). There was no difference in S(P5P)nd U(4PA)etween the groups after protein loading. CONCLUSION: Approximately one third of ICSFs with or without so-called MMH are sensitive to meat protein in terms of oxalate excretion, as opposed to healthy subjects. Mechanisms underlying this sensitivity to meat protein remain to be elucidated and do not seem to involve vitamin B(6) deficiency.


Subject(s)
Calcium/urine , Dietary Proteins/adverse effects , Hyperoxaluria/etiology , Kidney Calculi/etiology , Meat/adverse effects , Adult , Diet, Protein-Restricted , Dietary Proteins/pharmacokinetics , Glycolates/urine , Humans , Hyperoxaluria/diet therapy , Hyperoxaluria/metabolism , Kidney Calculi/diet therapy , Kidney Calculi/metabolism , Male , Middle Aged , Oxalates/urine , Pyridoxal Phosphate/urine , Pyridoxic Acid/urine , Pyridoxine/metabolism , Sulfates/urine
5.
Klin Med (Mosk) ; 69(10): 74-7, 1991 Oct.
Article in Russian | MEDLINE | ID: mdl-1766225

ABSTRACT

Extremely high frequency (EHF) radiation was performed in 95 outpatients with duodenal ulcer. Individual choice of the exposure site can improve the treatment results. The syndrome-oriented approach of the Chinese conventional medicine warrants an effective choice of the acupuncture loci and the prognosis of the outcome. A clinical syndrome was identified in which healing of the ulcer was achieved on week two of the treatment in 92.3 +/- 7.7% of the patients. It is suggested that EHF therapy provides positive responses in case of a valid exposure zone selection, the frequency being less important.


Subject(s)
Duodenal Ulcer/radiotherapy , Electromagnetic Fields , Adolescent , Adult , Evaluation Studies as Topic , Female , Humans , Male , Middle Aged , Time Factors
9.
J Genet Hum ; 23(1): 43-58, 1975 Mar.
Article in French | MEDLINE | ID: mdl-1165479

ABSTRACT

We have demonstrated a method for the estimation of the frequency, in any population, of female carriers of recessive conditions associated with the X chromosome. This estimation is possible, independently of the fertility (f) of carriers of the gene, when the frequency of the affection among men is known. (See article) The expected proportions under various conditions are shown in the formulae.


Subject(s)
Gene Frequency , Genes, Recessive , Sex Chromosomes , Female , Fertility , Heterozygote , Homozygote , Humans , Male , Models, Biological , Pedigree
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