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11.
Tracer studies using 32 P labelled superphosphate and rock phosphate were conducted in microplots in a field experiment on rice-rice-greengram cropping system. The trial revealed that in all the rice crops studied, P uptake and P use efficiency were higher in superphosphate treated plots than in rock phosphate applied ones. P uptake was improved with organic manuring through application of green manure or crop residues like long rice stubbles. While superphosphate performed well either with or without organic manuring, rock phosphate performed fairly well only with organic manuring. Fairly good P use efficiency could be obtained in the system when green manuring and rock phosphate application in the first crop was followed by superphosphate and long stubble incorporation in the second crop. Apparent recovery values also showed nearly the same results. But tracer studies were found to be definitely superior in the evaluation of fertilizers. 相似文献
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Estimating the mass of asteroid 253 mathilde from tracking data during the NEAR flyby 总被引：1，自引：0，他引：1
DK Yeomans J Barriot DW Dunham RW Farquhar JD Giorgini CE Helfrich AS Konopliv JV McAdams JK Miller WM Owen DJ Scheeres SP Synnott BG Williams 《Science (New York, N.Y.)》1997,278(5346):2106-2109
The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter. 相似文献
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A group of 19 Merino rams was used to determine: (i) if body weight, age and testis characteristics are different between high (HR) and low-ranked (LR) rams, and (ii) how the competition between HR and LR rams for oestrous ewes affect their courtship and mating behaviour. Hierarchy was determined using the food competition test. The five first and five last ranked rams were individually exposed to oestrous ewes in pen tests, and the frequency of different courtship behavioural units, mounts and mates, and the time from test onset to each mate was recorded. The sexual behaviour of the five first ranked and the five last ranked rams was also tested in competition, pairing a HR and a LR ram. Age, body weight, body condition score, scrotal circumference, and testis firmness and resilience from HR and LR were not different. The display of courtship behavioural units was lower when rams were tested in competition but was not affected by the rank of the rams. The number of mates per test from HR rams was lower than that observed in LR rams when tested alone. While the number of mates decreased in LR rams in competition tests, it was not affected in HR rams. In summary, there was no relation between social rank and body weight, age or testis characteristics. LR rams were more effective than HR rams when mating oestrous ewes without competition. However, in competitive tests, although all rams modified their courtship strategies, LR rams were more affected by the presence of dominant rams than HR rams were by the presence of LR rams. 相似文献
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ABSTRACTA long-term fertilizer experiment was initiated in kharif 2007 in a maize–wheat sequence at the Experimental Farm of Department of Soil Science, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya, Palampur under the network of All India Coordinated Research Project on Soil Test Crop Response (STCR) Correlation Studies. The experiment consisted of eight treatments (control, general recommended dose, soil test based, farmers’ practice, target yield of 25 (rabi)/30 (kharif) and 35 (rabi)/40 (kharif) q ha?1 either with or without 5 t ha?1 farm yard manure) replicated thrice in a randomized block design. All the passive and active pools of soil organic matter (SOM) were highest under STCR treatments for target yield 35 q ha?1 + farmyard manure (FYM). The highest value of both humic and fulvic acids under STCR treatment for target yield 35 q ha?1 with FYM was statistically at par with treatment for target yield 25 q ha?1 with FYM. The R2 value indicated that about 96% to 98% of the total variation in grain yield was attributable to SOM fractions. The contribution of all fractions of SOM towards the total variation in straw yield was 96% to 97%. 相似文献
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Cook AF Shoemaker EM Smith BA Danielson GE Johnson TV Synnott SP 《Science (New York, N.Y.)》1981,211(4489):1419-1422
A quadruple long exposure of Io in eclipse exhibits faint auroral emission from the eruptive plumes. No luminous spots in the vents, predicted by Gold, were observed. Heat from the interior of Io appears to be the predominant source of energy in the plumes. 相似文献
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Caio JX Abimussi Thais M Menegheti Juliana T Wagatsuma Beatriz P Floriano André MM Arruda Paulo SP dos Santos Valéria NLS Oliva 《Veterinary anaesthesia and analgesia》2014,41(5):516-525
ObjectiveTo compare two concentrations of ropivacaine administered for tumescent local anesthesia (TLA) in dogs undergoing mastectomy.Study designProspective randomized clinical study.AnimalsSeventeen bitches of various breeds, aged 12 ± 2 years and weighing 10 ± 6.5 kg requiring total unilateral or bilateral mastectomy.MethodsDogs were premedicated with acepromazine (0.04 mg kg?1) and morphine (0.4 mg kg?1) intramuscularly. Anesthesia was induced with propofol (2.5 mg kg?1) and midazolam (0.2 mg kg?1) intravenously, followed by intubation and maintenance with isoflurane and TLA. Dogs were randomly allocated to receive TLA either with 0.1% ropivacaine (group G1) or with 0.05% ropivacaine (group G05). TLA was performed by insertion of a multihole needle under the skin and infusion of ropivacaine and lactated Ringer’s solution at a fixed volume of 15 mL kg?1. Ropivacaine concentrations in arterial blood were measured by high-performance liquid chromatography. Post-operative pain was assessed using two scales (University of Melbourne pain scale and a modified composite measure pain scale) and von Frey filaments, 4 hours after TLA and at 1 hour intervals until sensitivity was regained. A score above 30% of the maximum possible score was considered a positive indicator of pain.ResultsPeak plasma concentrations of ropivacaine were measured 240 minutes after TLA in G1. Low concentrations were measured in G05 for 60 minutes, with subsequent increase. Analgesic rescue and return of sensitivity occurred at 7 ± 2.3 and 7 ± 1.9 hours (mean ± SD) after TLA for G1 and G05, respectively.Conclusions and clinical relevanceTumescent local anesthesia with ropivacaine provided satisfactory post-operative analgesia that lasted for several hours, with no difference in duration between the concentrations. No serious side effects were attributed to TLA. Results indicated that 0.05% ropivacaine provided adequate analgesia for mastectomy, however, more studies are required to support this conclusion. 相似文献
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R Bathgate N Mace K Heasman G Evans WMC Maxwell SP de Graaf 《Reproduction in domestic animals》2013,48(6):893-898
Successful sex‐sorting of goat spermatozoa and subsequent birth of pre‐sexed kids have yet to be reported. As such, a series of experiments were conducted to develop protocols for sperm‐sorting (using a modified flow cytometer, MoFlo SX®) and cryopreservation of goat spermatozoa. Saanen goat spermatozoa (n = 2 males) were (i) collected into Salamon's or Tris catch media post‐sorting and (ii) frozen in Tris–citrate–glucose media supplemented with 5, 10 or 20% egg yolk in (iii) 0.25 ml pellets on dry ice or 0.25 ml straws in a controlled‐rate freezer. Post‐sort and post‐thaw sperm quality were assessed by motility (CASA), viability and acrosome integrity (PI/FITC‐PNA). Sex‐sorted goat spermatozoa frozen in pellets displayed significantly higher post‐thaw motility and viability than spermatozoa frozen in straws. Catch media and differing egg yolk concentration had no effect on the sperm parameters tested. The in vitro and in vivo fertility of sex‐sorted goat spermatozoa produced with this optimum protocol were then tested by means of a heterologous ova binding assay and intrauterine artificial insemination of Saanen goat does, respectively. Sex‐sorted goat spermatozoa bound to sheep ova zona pellucidae in similar numbers (p > 0.05) to non‐sorted goat spermatozoa, non‐sorted ram spermatozoa and sex‐sorted ram spermatozoa. Following intrauterine artificial insemination with sex‐sorted spermatozoa, 38% (5/13) of does kidded with 83% (3/5) of kids being of the expected sex. Does inseminated with non‐sorted spermatozoa achieved a 50% (3/6) kidding rate and a sex ratio of 3 : 1 (F : M). This study demonstrates for the first time that goat spermatozoa can be sex‐sorted by flow cytometry, successfully frozen and used to produce pre‐sexed kids. 相似文献
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CB Johnson KJ Stafford SP Sylvester RN Ward S Mitchinson DJ Mellor 《New Zealand veterinary journal》2013,61(6):433-437
AIM: To use the electroencephalogram (EEG) to ascertain whether the response of the cerebral cortex to the noxious stimulus of castration varied with age in lambs. METHODS: Two groups of East Friesian lambs were selected according to age; the mean age of the younger group (n=21) was 12 (SD 2) days and the older group (n=20) was 29 (SD 1) days. Anaesthesia was induced via mask using 4% halothane in oxygen, and maintained using 1.5% halothane in oxygen at a flow rate of 4 L/min. Once a stable plane of anaesthesia had been achieved, data collection of EEG and electrocardiographic (ECG) readings commenced, and the lambs were castrated 15 min later, using rubber rings. Median and 95% spectral edge frequencies (F95) and total EEG power (ptot) were derived from data from the EEG. RESULTS: Following castration, there was an increase in the median frequency (F50) in the younger lambs (p=0.002), and an increase in ptot in both groups (p=0.05), which was of greater magnitude in the older lambs. There were no significant changes in the F95. Both younger and older lambs exhibited a transient bradycardia (p=0.001 and p=0.01, respectively). CONCLUSIONS: These differences in the cortical response between the two groups suggest that 2-week-old lambs undergo a qualitatively different perception of the noxious stimulus of castration compared to 4-week-old lambs. 相似文献
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Abstract CASE HISTORY: In 2008, a 3-year-old female Labrador Retriever was presented for routine breeding soundness evaluation. CLINICAL FINDINGS: Vaginal endoscopy revealed an 8-cm long and 1-cm thick vaginal septum. Surgical resection of the septum was performed under general anaesthesia using a bipolar high-frequency resectoscope. Three months later the bitch was naturally mated and subsequently delivered five male and two female puppies without complications. Both female puppies were examined at the age of 12 and 15 months and showed a vaginal septum with a diameter of 0.3 and 0.5 cm, respectively. DIAGNOSIS: Vaginal septa in three related bitches. CLINICAL RELEVANCE: This is the first report describing the use of a bipolar high-frequency resectoscope for vaginal surgery in dogs. The septum could be resected quickly, with preservation of surrounding structures. Furthermore, it is the first report collecting information about familial presentation of vaginal septa in female dogs. Based on this case, we suggest that consideration should be given to the possible risk of inheritance of vaginal septa before considering surgical resection and breeding of female dogs. 相似文献