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1.
Nano Lett ; 15(3): 2168-73, 2015 Mar 11.
Article in English | MEDLINE | ID: mdl-25705928

ABSTRACT

An operando electrochemical stage for the transmission electron microscope has been configured to form a "Li battery" that is used to quantify the electrochemical processes that occur at the anode during charge/discharge cycling. Of particular importance for these observations is the identification of an image contrast reversal that originates from solid Li being less dense than the surrounding liquid electrolyte and electrode surface. This contrast allows Li to be identified from Li-containing compounds that make up the solid-electrolyte interphase (SEI) layer. By correlating images showing the sequence of Li electrodeposition and the evolution of the SEI layer with simultaneously acquired and calibrated cyclic voltammograms, electrodeposition, and electrolyte breakdown processes can be quantified directly on the nanoscale. This approach opens up intriguing new possibilities to rapidly visualize and test the electrochemical performance of a wide range of electrode/electrolyte combinations for next generation battery systems.

2.
Appetite ; 31(2): 159-70, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9792730

ABSTRACT

During the fasting month of Ramadan, Muslims abstain from food and drink from sunrise until sunset. This change of eating pattern provides an opportunity to investigate factors controlling hunger and thirst. A group of healthy Muslims (15 men and 26 women) living in Reading, U.K. made hourly ratings of their hunger, mood and thirst, and recorded their food and drink intake on specified days before, during and after Ramadan between January and March 1996. There were no significant changes in body weight over Ramadan. Rated hunger increased substantially during the daily fast, and hunger was higher for the women than the men during the earlier days of Ramadan, whereas later, on average, fasting levels of hunger were very similar for both sexes (significant gender x day interaction,p<0. 001). During Ramadan, the men tended to spend much of their time away from home, and may therefore have largely avoided eating-related cues during the daily fast. The women, however, were frequently involved in preparing food to be eaten later after sunset, which suggests an explanation for the results based on the external cue control of hunger. That is, unreinforced exposure to food cues in this context may have led to a decrease in the capacity of these cues to stimulate hunger.


Subject(s)
Appetite/physiology , Feeding Behavior/physiology , Food Preferences/physiology , Adult , Affect/physiology , Cues , Fasting , Female , Humans , Islam , Male , Middle Aged , Sex Factors , Thirst/physiology
3.
Int J Eat Disord ; 21(1): 77-82, 1997 Jan.
Article in English | MEDLINE | ID: mdl-8986520

ABSTRACT

OBJECTIVE: The current study investigated whether a concern with body shape and weight represents a distinct affective state, or whether it is better conceptualized as a highly specific form of anxiety. METHOD: The color-naming performance of women with a high Drive for Thinness score was examined under three experimental conditions: when a photograph of chocolate was present, when actual chocolate was present, and a control condition. High Drive for Thinness subjects demonstrated relatively impaired color naming of body shape words in the picture condition, but not in the food or control conditions. RESULTS: Although there was a significant impairment in the color naming of food words, this was unaffected by condition or degree of Drive for Thinness. DISCUSSION: The results are interpreted as supporting an analogy between weight/body shape concerns and subclinical phobic anxiety.


Subject(s)
Body Image , Color Perception , Food , Mood Disorders/psychology , Phobic Disorders/psychology , Vocabulary , Adolescent , Adult , Female , Humans , Mood Disorders/diagnosis , Phobic Disorders/diagnosis
4.
J Dairy Sci ; 80(12): 3308-15, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9436113

ABSTRACT

The objective of this study was to compare utilization of red clover (Trifolium pratense L.) and alfalfa (Medicago sativa L.) by lactating dairy cows. Red clover and alfalfa were harvested and conserved as silage at two maturities in 2 consecutive yr. Each year, diets containing experimental forages and supplemental grain were fed to 16 multiparous Holstein cows in early lactation in a replicated 4 x 4 Latin square lactation trial. Lactation performance and nutrient intake responses caused by forage type (red clover vs. alfalfa), maturity (early vs. late), and equivalent acid detergent fiber (ADF) content (yr 1, late alfalfa vs. late red clover; yr 2, early alfalfa vs. late red clover) were compared. Milk yield was not different between cows fed red clover or alfalfa in yr 1, but milk yield was higher for cows fed red clover in yr 2. When cows were fed alfalfa and red clover with similar ADF content, the milk yield of cows fed red clover was lower than that of cows fed alfalfa in yr 1, and milk yields were similar between cows fed alfalfa and red clover in yr 2. Milk protein yield and percentage were lower for cows fed red clover in yr 1 and 2, respectively. Intake of ADF and neutral detergent fiber was lower for cows fed red clover in both years. When red clover contained the same ADF content as did alfalfa, cows fed red clover ate less ADF, neutral detergent fiber, and dry matter, resulting in lower milk yield potential.


Subject(s)
Animal Feed , Animal Nutritional Physiological Phenomena , Lactation/physiology , Medicago sativa , Silage , Animals , Cattle , Dietary Fiber/administration & dosage , Dietary Fiber/metabolism , Dietary Proteins/administration & dosage , Digestion , Female , Fermentation , Hydrogen-Ion Concentration , Milk Proteins/analysis
5.
J Dairy Sci ; 76(9): 2632-43, 1993 Sep.
Article in English | MEDLINE | ID: mdl-8227665

ABSTRACT

Eight forages (alfalfa, birdsfoot trefoil, red clover, bromegrass, orchardgrass, perennial ryegrass, quackgrass, and timothy) at three maturities were evaluated for ruminal DM, CP, and NDF degradation kinetics. Duplicate dacron bags were incubated for 0, 3, 6, 10, 13, 25, 48, and 72 h in two late lactation Holstein cows fitted with ruminal cannulas over eight experimental periods. Species and maturity effects were observed for soluble, slow, and undegraded fractions; degradation rate; and ruminally degradable DM, CP, and NDF. Significant species by maturity interactions also were evident for fractions and ruminal degradabilities of DM, CP, and NDF. Legumes exhibited more extensive ruminal DM degradation than did grasses. No clear trends were evident in rate of ruminal CP degradation between legumes and grasses. Mature grasses were lowest in ruminally degradable CP. Legumes exhibited a higher undegraded fraction and faster degradation rate of slowly degraded NDF fractions, resulting in similar ruminally degraded NDF for legumes and grasses. Extensive differences in ruminal degradation kinetics existed between perennial legume and grass species and maturities. Species by maturity interactions were diverse, making categorization of degradation characteristics of legumes and grasses difficult.


Subject(s)
Animal Feed , Cattle/metabolism , Dietary Fiber , Dietary Proteins/metabolism , Rumen/metabolism , Animals , Digestion , Kinetics , Medicago sativa , Poaceae/metabolism
6.
J Wildl Dis ; 28(1): 95-101, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1548808

ABSTRACT

Six fallow deer (Dama dama) fawns died after receiving 25 to 150 infective larvae of Parelaphostrongylus tenuis. Fawns given higher doses usually died sooner (6 to 23 days) than those given lower doses (54 to 67 days). Early deaths were associated with severe acute peritonitis resulting from perforation of the intestinal wall; later deaths were associated with paralysis and inability to rise. Numerous adult P. tenuis were found within neural tissues of the brain and spinal cord in the three fawns with paralysis. One white-tailed deer (Odocoileus virginianus) exposed to infective larvae from the same source survived infection without exhibiting clinical signs and began passing larvae in feces 88 days post-exposure. At the doses used in this study, meningeal worm caused fatal infections in fallow deer. Results are compared to published observations of fallow deer naturally-infected with P. tenuis.


Subject(s)
Deer/parasitology , Metastrongyloidea/physiology , Nematode Infections/veterinary , Abomasum/pathology , Animals , Brain/parasitology , Brain/pathology , Intestine, Small/pathology , Lung/pathology , Meninges/pathology , Nematode Infections/mortality , Nematode Infections/parasitology , Peritoneal Diseases/pathology , Peritoneal Diseases/veterinary , Peritoneum/pathology , Spinal Cord/parasitology , Spinal Cord/pathology , Tissue Adhesions/pathology , Tissue Adhesions/veterinary
7.
J Wildl Dis ; 27(3): 446-51, 1991 Jul.
Article in English | MEDLINE | ID: mdl-1920665

ABSTRACT

Hides of nine elk, collected during the winter of 1986-1987 from the National Elk Refuge, Wyoming (USA) were examined for ectoparasites. Parasites recovered were mites, Psoroptes sp. (five elk); lice, Solenopotes ferrisi and Bovicola (Bovicola) longicornis (seven elk); and winter ticks, Dermacentor albipictus (nine elk). Three elk with severe scabies had an estimated 0.6 x 10(6), 3.8 x 10(6) and 6.5 x 10(6) mites, respectively. Densities of mites were much higher in skin regions with severe dermatitis. Skin lesions on elk with scabies consisted of dense, often moist, scabs extending along the dorsal and lateral thoracic regions of the body. Lesions attributed to winter ticks consisted of broken hair and alopecia on the dorsal portion of the lower neck, often extending in a "collar" around the neck.


Subject(s)
Deer/parasitology , Lice Infestations/veterinary , Mite Infestations/veterinary , Tick Infestations/veterinary , Animals , Anoplura , Dermacentor , Female , Lice Infestations/epidemiology , Lice Infestations/pathology , Male , Mite Infestations/epidemiology , Mite Infestations/pathology , Nymph , Phthiraptera , Skin/pathology , Tick Infestations/epidemiology , Tick Infestations/pathology , Wyoming/epidemiology
8.
J Wildl Dis ; 26(4): 535-7, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2250330

ABSTRACT

Dorsal-spined larvae in fecal samples from free-ranging white-tailed deer (Odocoileus virginianus) in Michigan and Pennsylvania were used as a source of larvae to infect a hand-raised white-tailed deer fawn. The fawn receive 200 third-stage larvae and passed dorsal-spined larvae in feces 66 days later. Muscleworm (Parelaphostrongylus andersoni), and meningeal worm (Parelaphostrongylus tenuis) were recovered at necropsy. Two white-tailed deer and seven wapiti (Cervus elaphus) exposed to larvae of the source from Pennsylvania harbored only P. tenuis. This is the first report of P. andersoni in the midwestern United States and extends the known range of this muscleworm in free-ranging white-tailed deer. Concurrent infections of P. andersoni and P. tenuis have not been established previously in experimentally infected fawns.


Subject(s)
Deer/parasitology , Nematode Infections/veterinary , Animals , Brain/parasitology , Feces/parasitology , Female , Male , Michigan/epidemiology , Muscles/parasitology , Nematoda/isolation & purification , Nematode Infections/epidemiology , Nematode Infections/parasitology , Spinal Cord/parasitology
9.
J Med Entomol ; 27(4): 656-60, 1990 Jul.
Article in English | MEDLINE | ID: mdl-2388241

ABSTRACT

Fasting metabolic rates, respiration rates, respiratory minute volumes, and fasted weights were measured on three yearling moose (Alces alces (L.)) (Artiodactyla: Cervidae) infested with 50,000 winter ticks. Dermacentor albipictus (Packard) (Acari: Ixodidae), and on two uninfested controls. Infestations produced no detectable effects on fasting metabolic rates or weight changes. The influence of tick-induced alopecia on lower critical temperatures could not be assessed because of warm temperatures during the winter and spring trials. Destruction of winter hair accompanied a reduction in respiratory minute volumes and respiration rates of heat-stressed moose.


Subject(s)
Alopecia/veterinary , Deer/parasitology , Energy Metabolism , Tick Infestations/veterinary , Alopecia/etiology , Alopecia/metabolism , Animals , Dermacentor , Tick Infestations/complications
10.
J Wildl Dis ; 26(3): 410-1, 1990 Jul.
Article in English | MEDLINE | ID: mdl-1974936

ABSTRACT

Infestations of winter ticks (Dermacentor albipictus) on two captive reindeer (Rangifer tarandus tarandus) are reported and may be associated with increased grooming and alopecia. Over 400,000 ticks were recovered from one reindeer. Few ticks (less than 25 ticks/animal) were found on three free-ranging woodland caribou (Rangifer tarandus caribou).


Subject(s)
Reindeer/parasitology , Tick Infestations/veterinary , Alberta/epidemiology , Animals , Dermacentor/isolation & purification , Female , Male , Tick Infestations/epidemiology
11.
Int J Parasitol ; 19(6): 691-3, 1989 Sep.
Article in English | MEDLINE | ID: mdl-2807724

ABSTRACT

Densities of winter ticks (Dermacentor albipictus) were determined on each of 20 moose (Alces alces) half-hides by dissolving 100 cm2 quadrats in potassium hydroxide solution. Data were then used to determine the optimum sampling fraction for estimating tick densities. Random sampling was applied to 20 additional half-hides of known tick density to assess the accuracy of the estimates. We conclude that random sampling of 15% of the quadrats produces a good estimate of tick density. Total numbers of ticks were highly correlated with tick density.


Subject(s)
Deer/parasitology , Dermacentor/growth & development , Skin/parasitology , Animals , Evaluation Studies as Topic , Parasitology/methods , Random Allocation , Ticks
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