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31.
Tillage loosens soil to depths of 75–150 mm (3–6 in.). As the soil is tilled, the failure path precedes the motion of the tillage tool. Previous studies have examined soil forces acting on a tine by predicting different soil failure patterns. This paper quantifies the rate and the path of the cracks associated with soil failure front. The propagation of the soil failure path by observing the temporal profile of the leading edge of the failure crack with respect to the tool motion was examined. Crack propagations were analysed for sweep operating at 4 km h−1 speed, and two operating depths of 75 and 100 mm using high-speed digital videography. Higher depth of operation showed distinct phases for crack development and propagation. Short and intermittent soil crack propagation with lower propagation growth rates was observed for shallow depth of operation. Crack growth rate has been observed to have a sinusoidal relation with time. 相似文献
32.
Rawlings CA Mahaffey MB Barsanti JA Canalis C 《Journal of the American Veterinary Medical Association》2003,222(6):759-61, 737
Urinary calculi were removed by means of laparoscopic-assisted cystoscopy in 3 dogs. Two small abdominal incisions were made--1 for a laparoscope and 1 for placement of a Babcock forceps to aid in grasping and lifting the urinary bladder to the abdominal wall. A cystoscope and instruments for calculi removal were passed through a small cystotomy. Biopsy of the urinary bladder or other abdominal organs could also be performed by use of this technique. Laparoscopic-assisted cystoscopy was minimally invasive and provided clear images of the mucosal surface of the urinary bladder and proximal portion of the urethra for easy retrieval of urinary calculi. An imaging procedure should be performed to ensure complete removal of calculi. 相似文献
33.
The present study was conducted to investigate the physiological responses of Vigna radiata L. to UV-B radiation and salicylic acid (SA) alone and in combination. The exposure of the seedlings to UV-B radiation significantly reduced biophysical parameters. The pigments viz., chlorophylls and carotenoids and protein decreased while sugar content increased in the seedlings on UV-B exposure. UV-B stress increased the activities of superoxide dismutase, catalase and peroxidase. SA appears to mitigate the adverse effect of UV-B radiation on the growth and metabolism of Vigna seedlings. 相似文献
34.
35.
Ram B. Kushwaha Ajay K. GuptaAnkur Sharma MVSc Dinesh K. DwivediPankaj Gupta MVSc Hans R. Bhardwaj PhD 《Journal of Equine Veterinary Science》2014
A 7-year-old mare was brought to the clinic with a history of falling 1 month earlier and bilateral mucosanguinous nasal discharge, respiratory distress, and bilateral swelling caudal to the posterior margin of vertical rami of mandibles for 3 weeks. Lateral radiography of the neck region revealed gas-filled soft tissue density caudal to the mandibles. Empyema of the guttural pouches was diagnosed and surgical drainage was planned by placement of a fenestrated tube. A skin incision was made at the dependent part of the swelling in Viborg's triangle on both sides; guttural pouches were exposed and mucosanguinous contents drained by lancing the pouches. Fenestrated tubes, prepared from the tubing of a urine collection bag, were fixed into the guttural pouches by anchoring to the wall of the pouches and skin. Postoperatively, 5 g of streptomycin plus 4 million IU of penicillin and 75 mg of meloxicam were administered intramuscularly for 7 days and 5 days, respectively. Guttural pouches were lavaged daily with 0.1% potassium permanganate solution (KMnO4) and 5% topical povidone iodine diluted with normal saline solution to 1%. Tubes from both sides were removed on the 14th postoperative day, and wounds healed by second intention. The animal recovered uneventfully. 相似文献
36.
S. V. Chanda K. Joshi P. P. Vaishnav Y. D. Singh 《Journal of Agronomy and Crop Science》1987,159(5):312-319
The factors controlling productivity (dry matter production) in a pearl millet ( Pennisetum americanum L. Leeke) hybrid BJ-104 and its inbred parents, J-104 and 5141-A , were investigated using the harvest interval and curve-fitting methods. During initial stages, the hybrid showed highest total dry weight, leaf dry weight and leaf area, than the inbred lines. However, with age these differences decreased considerably. The male parent attained total dry weight almost equal to the hybrid by d 45, whereas the female parent attained it by d59.
The derived growth parameters like RGR, LAR, LWR and SLA showed strong ontogenic decline. Further, considerable cultivar variations were also recorded. Importance of the growth parameters in determining productivity is discussed and it is emphasized that higher accumulation of dry matter during initial seedling stages may be an important factor. 相似文献
The derived growth parameters like RGR, LAR, LWR and SLA showed strong ontogenic decline. Further, considerable cultivar variations were also recorded. Importance of the growth parameters in determining productivity is discussed and it is emphasized that higher accumulation of dry matter during initial seedling stages may be an important factor. 相似文献
37.
Tiago de Oliveira F Chanda A Banerjee D Shan X Mondal S Que L Bominaar EL Münck E Collins TJ 《Science (New York, N.Y.)》2007,315(5813):835-838
Iron(V)-oxo species have been proposed as key reactive intermediates in the catalysis of oxygen-activating enzymes and synthetic catalysts. Here, we report the synthesis of [Fe(TAML)(O)]- in nearly quantitative yield, where TAML is a macrocyclic tetraamide ligand. Mass spectrometry, M?ssbauer, electron paramagnetic resonance, and x-ray absorption spectroscopies, as well as reactivity studies and density functional theory calculations show that this long-lived (hours at -60 degrees C) intermediate is a spin S = 1/2 iron(V)-oxo complex. Iron-TAML systems have proven to be efficient catalysts in the decomposition of numerous pollutants by hydrogen peroxide, and the species we characterized is a likely reactive intermediate in these reactions. 相似文献
38.
Langford DJ Crager SE Shehzad Z Smith SB Sotocinal SG Levenstadt JS Chanda ML Levitin DJ Mogil JS 《Science (New York, N.Y.)》2006,312(5782):1967-1970
Empathy is thought to be unique to higher primates, possibly to humans alone. We report the modulation of pain sensitivity in mice produced solely by exposure to their cagemates, but not to strangers, in pain. Mice tested in dyads and given an identical noxious stimulus displayed increased pain behaviors with statistically greater co-occurrence, effects dependent on visual observation. When familiar mice were given noxious stimuli of different intensities, their pain behavior was influenced by their neighbor's status bidirectionally. Finally, observation of a cagemate in pain altered pain sensitivity of an entirely different modality, suggesting that nociceptive mechanisms in general are sensitized. 相似文献
39.
Prospective evaluation of laparoscopic-assisted gastropexy in dogs susceptible to gastric dilatation 总被引:1,自引:0,他引:1
Rawlings CA Mahaffey MB Bement S Canalis C 《Journal of the American Veterinary Medical Association》2002,221(11):1576-1581
OBJECTIVE: To determine long-term outcome associated with laparoscopic-assisted gastropexy in prevention of gastric dilatation-volvulus (GDV) in susceptible dogs and to evaluate use of laparoscopy to correct GDV. DESIGN: Prospective study. ANIMALS: 25 client-owned large-breed dogs. PROCEDURE: 23 dogs susceptible to GDV were referred as candidates for elective gastropexy. These dogs had a history of treatment for gastric dilatation, clinical signs of gastric dilatation, or family members with gastric dilatation. Laparoscopic-assisted gastropexy was performed. One year after surgery, abdominal ultrasonography was performed to evaluate the attachment of the stomach to the abdominal wall. Two dogs with GDV were also treated with laparoscopic-assisted derotation of the stomach and gastropexy. RESULTS: None of the dogs developed GDV during the year after gastropexy, and all 20 dogs examined ultrasonographically had an intact attachment. Another dog was euthanatized at 11.5 months for unrelated problems. Two dogs with GDV successfully underwent laparoscopic-assisted gastropexy after the stomach was repositioned. CONCLUSIONS AND CLINICAL RELEVANCE: Laparoscopic-assisted gastropexy resulted in a persisting attachment between the stomach and abdominal wall, an absence of GDV development, and few complications. Dogs with a high probability for development of GDV should be considered candidates for minimally invasive gastropexy. Carefully selected dogs with GDV can be treated laparoscopically. 相似文献
40.
J. Perkins M. Reed L. Akanyang J. Atlhopheng R. Chanda L. Magole W. Mphinyane K. Mulale R. Sebego L. Fleskens B. Irvine M. Kirkby 《Land Degradation \u0026amp; Development》2013,24(5):463-477
It is increasingly recognised that tackling land degradation through more sustainable land management depends on incorporating multiple perspectives by using a variety of methods at multiple scales, including the perspectives of those who manage and/or use the land. This paper reports experience implementing a previously proposed methodological framework that is designed to facilitate knowledge sharing between researchers and stakeholders about land degradation severity and extent, and sustainable land management options. Empirical findings are presented from the Botswana site of the EU‐funded Desertification Mitigation and Remediation of Land project. The paper reflects upon the challenges and benefits of the proposed framework and identifies a number of benefits, notably related to insights arising from the integration of local and scientific knowledge, and the ownership of the sustainable land management strategies that emerged from the process. However, implementing the framework was not without challenges, and levels of poverty and formal education may limit the implementation of the framework in some developing world contexts. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献