Weed seed inactivation in soil mesocosms via biosolarization with mature compost and tomato processing waste amendments          下载免费PDF全文

Yigal Achmon  Jesús D Fernández‐Bayo  Katie Hernandez  Dlinka G McCurry  Duff R Harrold  Joey Su  Ruth M Dahlquist‐Willard  James J Stapleton  Jean S VanderGheynst  Christopher W Simmons 《Pest management science》2017,73(5):862-873

  相似文献   

Effect of management of organic wastes on inactivation of Brassica nigra and Fusarium oxysporum f.sp. lactucae using soil biosolarization          下载免费PDF全文

Jesus Dionisio Fernández‐Bayo  Tara E Randall  Duff R Harrold  Yigal Achmon  Kelley V Hestmark  Joey Su  Ruth M Dahlquist‐Willard  Thomas R Gordon  James J Stapleton  Jean S VanderGheynst  Christopher W Simmons 《Pest management science》2018,74(8):1892-1902

  相似文献   

Six separate sex chromosome anomalies in an Arabian mare     

L R Klunder  R A McFeely  J P Willard 《Equine veterinary journal》1990,22(3):218-220

  相似文献   

Recovery of alpine tundra under protection after damage by human activities in the rocky mountains of Colorado     

Beatrice E. Willard  Ph.D. 《Biological conservation》1971

Visitors to Rocky Mountain National Park are especially attracted to its easily accessible alpine tundra, which widely dominates the landscape above tree-limit. A remarkable summer highway, Trail Ridge Road, traverses more than twelve miles (19 km ) of tundra, rising in its highest tract to elevations of over 12,000 feet (3,658 m). Visitor activities are largely confined to the immediate vicinity of ‘black-top’ parking areas located at points of special interest, but many persons do venture out along the established pathways. Only a few visitors each year are venturesome enough, or take the time, to wander at leisure over the gently rolling land. Trampling by the visitors kills plants and initiates erosion processes which eventually remove all plants and the finer organic and mineral soil particles. The present study was undertaken to get information on the processes and rates involved in the recovery of the tundra when protected from further visitor effects by channelling their movement along paths, and by erecting exclosures. Observations made over a 4-year period showed almost complete recovery of vegetation which had been trampled for only one year. In an area which had been trampled for 26 years, there was an increase in vegetative growth, but the potentially dominant species, Kobresia myosuroides, still had reduced vigour, and some of the other important species in the natural association were still absent. One are that had been severely damaged during 38 years of trampling showed no improvement after four years of protection. The time-factor in tundra recovery is quite shocking. We estimate that some tundra that has been damaged by only a few seasons of human activity will require hundreds of years, possibly even a thousand, to rebuild a natural and persistent (climax) ecosystem.  相似文献   

Isolation-perfusion of ovine hind limbs. III. Perfusate lysine levels.     

J A Boling  J C Willard  W R Burris 《Journal of animal science》1977,45(4):832-836

  相似文献   

Natural selection of parental ability to vary the sex ratio of offspring   总被引：67，自引：0，他引：67  

R L Trivers  D E Willard 《Science (New York, N.Y.)》1973,179(68):90-92

Theory and data suggest that a male in good condition at the end of the period of parental investment is expected to outreproduce a sister in similar condition, while she is expected to outreproduce him if both are in poor condition. Accordingly, natural selection should favor parental ability to adjust the sex ratio of offspring produced according to parental ability to invest. Data from mammals support the model: As maternal condition declines, the adult female tends to produce a lower ratio of males to females.  相似文献   

Interobserver variation among histopathologic evaluations of intestinal tissues from dogs and cats   总被引：1，自引：0，他引：1  

Willard MD  Jergens AE  Duncan RB  Leib MS  McCracken MD  DeNovo RC  Helman RG  Slater MR  Harbison JL 《Journal of the American Veterinary Medical Association》2002,220(8):1177-1182

  相似文献   

Intestinal crypt lesions associated with protein-losing enteropathy in the dog     

Willard MD  Helman G  Fradkin JM  Becker T  Brown RM  Lewis BC  Weeks BR 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(3):298-307

Six dogs were diagnosed with protein losing enteropathy (PLE). There was no evidence of inappropriate inflammatory infiltrates or lymphangiectasia in multiple mucosal biopsies of the small intestine of 4 of the dogs. The 5th and 6th dogs had obvious lymphangiectasia and a moderate infiltrate of inflammatory cells in the intestinal mucosa. All 6 dogs had a large number of dilated intestinal crypts that were filled with mucus, sloughed epithelial cells, and/or inflammatory cells. Whether PLE occurs in these dogs because of protein lost from the dilated crypts into the intestinal lumen or whether the dilated crypts are a mucosal reaction due to another undetermined lesion that is responsible for alimentary tract protein loss is unknown. However, when large numbers of dilated intestinal crypts are present, they appear to be associated with PLE even if there are no other remarkable lesions in the intestinal mucosa.  相似文献   

Nutrient and mineral composition during shoot growth in seven species of Phyllostachys and Pseudosasa bamboo consumed by giant panda          下载免费PDF全文

A. L. Christian  K. K. Knott  C. K. Vance  J. F. Falcone  L. L. Bauer  G. C. Fahey Jr  S. Willard  A. J. Kouba 《Journal of animal physiology and animal nutrition》2015,99(6):1172-1183

During the annual period of bamboo shoot growth in spring, free‐ranging giant pandas feed almost exclusively on the shoots while ignoring the leaves and full‐ height culm. Little is known about the nutritional changes that occur during bamboo shoot growth, if nutritional changes differ among species, or how these changes might influence forage selection. Our objective was to examine the nutrient and mineral composition during three phases of shoot growth (<60, 90–150 and >180 cm) for seven species of bamboo (Phyllostachys (P.) aurea, P. aureosulcata, P. bissetii, P. glauca, P. nuda, P. rubromarginata, Pseudosasa japonica) fed to captive giant pandas at the Memphis Zoo. Total dietary fiber content of bamboo shoots increased (p < 0.0001) from an overall species average of 61% dry matter (DM) at < 60 cm to 75% DM at shoot heights > 180 cm, while crude protein, fat and ash exhibited significant declines (p < 0.05). Phyllostachys nuda had the overall greatest (p = 0.007) crude protein (21% DM) and fat (4% DM) content, and lowest overall total fibre (61% DM) content compared to the other species examined. In contrast, Pseudosasa japonica had the overall lowest crude protein and fat, and relatively higher fibre content (9%, 3% and 74% respectively). Concentrations of Zn and Fe were highest in shoots <60 cm (10–50 μg/g DM) and decreased (p < 0.05) during growth in all species examined. Concentrations of Ca, Cu, Mn, Na and K varied among species and were largely unaffected by growth stage. Due to their higher concentrations of nutrients and lower fibre content in comparison to culm and leaf, bamboo shoots should be a major component of captive giant panda diets when available.  相似文献   

Effect of strenuous exercise on urine concentrations of homovanillic acid, cortisol, and vanillylmandelic acid in sled dogs     

Durocher LL  Hinchcliff KW  Williamson KK  McKenzie EC  Holbrook TC  Willard M  Royer CM  Davis MS 《American journal of veterinary research》2007,68(1):107-111

OBJECTIVE: To determine whether prolonged exercise by conditioned sled dogs affects urine concentrations of homovanillic acid (a metabolite of dopamine), vanillylmandelic acid (a metabolite of norepinephrine and epinephrine), and cortisol. ANIMALS: 24 conditioned Alaskan sled dogs (2 to 8.5 years old) that were in training for a multiday endurance race. PROCEDURES: Voided urine samples were collected from 4 groups of dogs (randomly selected from 54 dogs) after no exercise (control group; n = 6 dogs), completion of a 160km run (group A; 3), completion of a 420-km run (group B; 7), and completion of a 560-km run (group C; 6). Urine cortisol concentrations were determined by use of an immunoassay technique; urine vanillylmandelic acid and homovanillic acid concentrations were measured via high-performance liquid chromatography. RESULTS: Compared with the control group, urine cortisol concentration in groups A, B, and C was significantly different (5.33 x 10(4) +/- 2.62 x 10(4) microg/dL vs 1.04 x 10(4) +/- 2.31 x 10(5) microg/dL, 8.88 x 10(4) +/- 5.49 x 10(4) microg/dL, and 6.31 x 10(4) +/- 5.09 x 10(4) microg/dL, respectively). Urine homovanillic acid concentration did not differ among the 4 groups. Vanillylmandelic acid was not detected in any urine samples. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that prolonged exercise by sled dogs did not affect urine homovanillic acid concentration but did increase urinary cortisol secretion, which is indicative of adrenocortical stimulation. The apparent lack of vanillylmandelic acid in voided urine samples requires further investigation.  相似文献