Energy: bechtel cost data     

Lovins AB 《Science (New York, N.Y.)》1979,204(4389):124-130

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Energy demand forecasts     

Lovins AB 《Science (New York, N.Y.)》1980,210(4469):480

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Energy: the "soft path"     

Lovins AB 《Science (New York, N.Y.)》1977,196(4297):1384-1385

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Stress and Parturition in the Pig*     

AB Lawrence  KA McLean  S Jarvis  CL Gilbert  JC Petherick 《Reproduction in domestic animals》1997,32(5):231-236

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The Effect of Season on Spermatozoa Motility,Plasma Membrane and Acrosome Integrity in Fresh and Frozen–Thawed Semen from Xinong Saanen Bucks          下载免费PDF全文

W Wang  J Luo  S Sun  L Xi  Q Gao  AB Haile  H Shi  W Zhang  H Shi 《Reproduction in domestic animals》2015,50(1):23-28

The aim of this study was to evaluate whether the season of ejaculate collection influences seminal quality parameters of pre‐ and post‐freeze–thawing in Xinong Saanen bucks. Ejaculates were collected from eight bucks throughout the four seasons (spring, summer, autumn and winter) in a 12 months’ time period, identified in the Northern Hemisphere. Semen samples were evaluated by the combinations of conventional and Computer‐Assisted Sperm Analysis (CASA) when fresh and after frozen–thawed, respectively. The results clearly demonstrated that season of ejaculate collection influenced (p < 0.05) fresh semen quality. Highest semen quality was observed during autumn. On the contrary, undesirable indices (significantly lower, p < 0.05) were observed in winter as compared with the other remaining seasons. CASA has clearly shown the influences of seasonal variations on semen motility parameters. Furthermore, season of ejaculate collection was also found to influence sperm freezability. Semen characteristics after frozen–thawed followed a similar pattern with that of fresh ejaculate except in spring. The results revealed that sperm quality was higher (p < 0.01) in summer and autumn than in spring and winter. In conclusion, seasonal variation influences semen quality in Xinong Saanen bucks. In addition to summer and autumn, fresh ejaculates in spring can also be successfully used for AI. Sperm from ejaculates collected during summer and autumn are more suitable for cryopreservation. Hence, it is possible to increase the efficiency of goat breeding by manipulating the seasonal variations of semen quality for immediate AI and/or cryopreservation.  相似文献   

RADIOGRAPHIC CHANGES IN TESTES OF BULLS INFECTED WITH BESNOITIOSIS   总被引：1，自引：0，他引：1  

Uri  Bargai  VMD AB  DVSc  Theodor  Nobel  DVM†  Shmuel  Pearl  DVM† 《Veterinary radiology & ultrasound》1984,25(5):235-239

Ten beef bulls infected with Besnoitiosis were examined radiographically and pathologically. Eight of these were slaughtered soon after diagnosis; two were left for a six-month observation period. The radiographic findings were focal and branching-tree calcification of the testes. Histopathologic examination proved these calcifications to be necrotic sections of the seminiferous tubules. Radiography of the testes as a means of evaluating the fertility status of the infected bull is recommended.  相似文献   

The Relationship Between Post‐Thaw Sperm DNA Integrity and Non‐Return Rate Among Norwegian Cross‐Bred Rams     

AB Nordstoga  A Krogens  A Ndtvedt  W Farstad  K Waterhouse 《Reproduction in domestic animals》2013,48(2):207-212

With the aim of investigating the relationship between sperm DNA integrity and non‐return rate (NRR) among Norwegian cross‐bred rams, semen from 15 individuals was examined by flow cytometry. Sperm Chromatin Structure Assay (SCSA) quantifies the proportion of spermatozoa with denatured DNA after in situ acid treatment, and the four parameters % DFI, % HDS, MEAN DFI and SD DFI are all different measures of DNA denaturation and maturation. Field fertility, reported as NRR 25 days after insemination was based on all inseminations from a large‐scale breeding programme and supplied by the Norwegian Association of Sheep and Goat Farmers. From each ram, four straws from four different weeks of the breeding season were analysed, and the associations between 25‐day NRR and the mean of the four SCSA parameters were tested using a logistic regression model. The results revealed no association between fertility and % DFI or % HDS, while SD DFI and MEAN DFI showed a significant negative association with NRR. Further, the SCSA values varied significantly between ejaculates within ram among some of the rams in the study. However, no significant association was seen between these intra‐individual differences in sperm DNA integrity and NRR. In conclusion, this study suggests an association between sperm DNA integrity and NRR for rams. However, further research must be conducted to confirm these findings and determine whether sperm DNA assessments can be applied to predict ram fertility.  相似文献   

Major compositional units of the moon: lunar prospector thermal and fast neutrons   总被引：2，自引：0，他引：2  

WC Feldman  BL Barraclough  S Maurice  RC Elphic  DJ Lawrence  DR Thomsen  AB Binder 《Science (New York, N.Y.)》1998,281(5382):1489-1493

Global maps of thermal and fast neutron fluxes from the moon suggest three end-member compositional units. A high thermal and low fast neutron flux unit correlates with the lunar highlands and is consistent with feldspathic rocks. The South Pole-Aitken basin and a strip that surrounds the nearside maria have intermediate thermal and fast neutron flux levels, consistent with more mafic rocks. There appears to be a smooth transition between the most mafic and feldspathic compositions, which correspond to low and high surface altitudes, respectively. The maria show low thermal and high fast neutron fluxes, consistent with basaltic rocks.  相似文献   

Lunar Fe and Ti abundances: comparison of lunar prospector and clementine data   总被引：3，自引：0，他引：3  

RC Elphic  DJ Lawrence  WC Feldman  BL Barraclough  S Maurice  AB Binder  PG Lucey 《Science (New York, N.Y.)》1998,281(5382):1493-1496

The Lunar Prospector neutron spectrometer data correlate well with iron and titanium abundances obtained through analysis of Clementine spectral reflectance data. With the iron and titanium dependence removed, the neutron spectrometer data also reveal regions with enhanced amounts of gadolinium and samarium, incompatible rare earth elements that are enriched in the final phases of magma crystallization. These regions are found mainly around the ramparts of the Imbrium impact basin but not around the other basins, including the much larger and deeper South Pole-Aitken basin. This result confirms the compositional uniqueness of the surface and interior of the Imbrium region.  相似文献   

Impact of Distillery Effluent on Soil Carbon and Nitrogen Dynamics in a Vertisol of Central India     

AK Biswas  Pankaj Sharma  KM Hati  S Ramana  AB Singh 《Communications in Soil Science and Plant Analysis》2018,49(17):2189-2196

Distilleries produce a huge quantity of effluents, popularly known as spent wash (SW), which when bio-methanated produce post-methanation effluents (PME). A field experiment on soybean–wheat system was conducted for five consecutive years in a Vertisol of central India to evaluate the effect of distillery effluent (DE) on soil carbon and nitrogen dynamics. Ten treatment combinations consisting of control, 100% NPK + Farmyard Manure (FYM), and graded level of SW and PME were applied. Total carbon content of soil increased significantly with applications of FYM and DE. SW was found superior in enhancing carbon content of soil in comparison to PME. Farmyard Manure contributed more carbon toward the recalcitrant pool, whereas DE contributed more carbon toward the active and slow pool. Nitrogen (N) availability was significantly improved with the application of DE. Balanced application of DE may act as amendment for increasing C and N stocks in Vertisol.  相似文献