Morphology, productivity and forage quality of Leucaena leucocephala as influenced by irrigation under field conditions     

Maher J. Tadros  Naji K. Al-Mefleh  Paul Chandler 《Agroforestry Systems》2012,86(1):73-81

A field study was conducted to investigate the effect of water deficit on the morphology, productivity, and quality of Leucaena leucocephala (Lam.) De Wit. Five main irrigation levels were applied based on actual evapotranspiration (AET): 0.25, 0.50, 0.75, 1.00, and 1.25 of the AET. Plant height, number of leaves and branches, and root length and diameter were measured. Fresh and dry weights were recorded at harvest, and crude protein was analyzed in leaves and roots. The results showed that morphological and yield characteristics were affected by the amount of water applied. The number of leaves remaining at the end of 21?weeks of growth was 65, 84, 93, 87 and 102 at 0.25, 0.50, 0.75, 1.00, and 1.25 AET. Root length and diameter increased with increasing irrigation. The greatest root length (66.5?cm) at 1.00 AET did not differ significantly from that at 1.25 AET (58.8?cm). The dry yield at 0.50, 0.75 and 1.00 AET showed an increased trend per plant in each treatment. Similarly, leaf crude protein showed a trend of increase with increasing irrigation although values were not significantly different between the levels of irrigation. The moisture content ranged from 60 to 63?% in leaves and 32?C35?% in branches across the five treatments. The analysis of water use efficiency showed that the 0.50 AET plants produced 2.6?kg?ha^?1?mm^?1 of dry forage compared to 1.8?kg?ha^?1?mm^?1 at 0.75 AET. The results showed that 0.50 or 0.75 AET represents the best irrigation level for L. leucocephala cultivation, producing a total dry yield of 0.68 and 0.72?t?ha^?1, respectively, in our study.  相似文献   

Laryngoplasty in Standing Horses          下载免费PDF全文

Fabrice Rossignol DVM  Dipl EVCS  Amélie Vitte DVM  Josef Boening DVM  Dipl ECVS  Michael Maher DVM  Antoine Lechartier DVM  Olivier Brandenberger DVM  Manuel Martin‐Flores DVM  Dipl ACVA  Hayley Lang DVM  Wade Walker DVM  Norm G. Ducharme DVM  Dipl ACVS 《Veterinary surgery : VS》2015,44(3):341-347

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Trends in cow numbers and culling rate in the Irish cattle population, 2003 to 2006     

Maher P  Good M  More S 《Irish veterinary journal》2008,61(7):455-463

Cows are the main economic production units of Ireland's cattle industry. Therefore, demographic information, including overall numbers and survival rates, are relevant to the Irish agricultural industry. However, few data are available on the demographics of cows within a national population, either in Ireland or elsewhere, despite the recent development of comprehensive national cattle databases in many EU Member States. This study has sought: to determine the rate of cow culling from the national herd; to determine the rate of culling by type (dairy, beef), age, method of exit, date of exit and interval between last calving and exit; to calculate the national cow on-farm mortality rate; and to compare the Irish rates with published data from other countries. This work was conducted using data recorded in the national Cattle Movement Monitoring System (CMMS). Culling refers to the exit of cows from the national herd, as a result of death but regardless of reason, and cow-culling rate was calculated as the number of cow exits (as defined above) each year divided by the number of calf births in the same year. Culling rate was determined by type (dairy or beef), date of birth, method of exit (slaughter or on-farm death), month of exit and interval between last calving and exit. The average cow-culling rate during 2003 to 2006 was 19.6% (21.3% for dairy, 18% for beef). While comparisons must be treated with caution, it concluded that the overall rates of culling in Ireland fell within published internationally accepted norms. The on-farm mortality rate of 3.2-4.1% was similar to that reported in comparable studies.  相似文献   

Lunar surface magnetic fields and their interaction with the solar wind: results from lunar prospector   总被引：1，自引：0，他引：1  

RP Lin  DL Mitchell  DW Curtis  KA Anderson  CW Carlson  J McFadden  MH Acuna  LL Hood  A Binder 《Science (New York, N.Y.)》1998,281(5382):1480-1484

The magnetometer and electron reflectometer experiment on the Lunar Prospector spacecraft has obtained maps of lunar crustal magnetic fields and observed the interaction between the solar wind and regions of strong crustal magnetic fields at high selenographic latitude (30 degreesS to 80 degreesS) and low ( approximately 100 kilometers) altitude. Electron reflection maps of the regions antipodal to the Imbrium and Serenitatis impact basins, extending to 80 degreesS latitude, show that crustal magnetic fields fill most of the antipodal zones of those basins. This finding provides further evidence for the hypothesis that basin-forming impacts result in magnetization of the lunar crust at their antipodes. The crustal magnetic fields of the Imbrium antipode region are strong enough to deflect the solar wind and form a miniature (100 to several hundred kilometers across) magnetosphere, magnetosheath, and bow shock system.  相似文献   

Bioactivity Potential of Marine Natural Products from Scleractinia-Associated Microbes and In Silico Anti-SARS-COV-2 Evaluation     

Eman Maher Zahran  Amgad Albohy  Amira Khalil  Alyaa Hatem Ibrahim  Heba Ali Ahmed  Ebaa M. El-Hossary  Gerhard Bringmann  Usama Ramadan Abdelmohsen 《Marine drugs》2020,18(12)

Marine organisms and their associated microbes are rich in diverse chemical leads. With the development of marine biotechnology, a considerable number of research activities are focused on marine bacteria and fungi-derived bioactive compounds. Marine bacteria and fungi are ranked on the top of the hierarchy of all organisms, as they are responsible for producing a wide range of bioactive secondary metabolites with possible pharmaceutical applications. Thus, they have the potential to provide future drugs against challenging diseases, such as cancer, a range of viral diseases, malaria, and inflammation. This review aims at describing the literature on secondary metabolites that have been obtained from Scleractinian-associated organisms including bacteria, fungi, and zooxanthellae, with full coverage of the period from 1982 to 2020, as well as illustrating their biological activities and structure activity relationship (SAR). Moreover, all these compounds were filtered based on ADME analysis to determine their physicochemical properties, and 15 compounds were selected. The selected compounds were virtually investigated for potential inhibition for SARS-CoV-2 targets using molecular docking studies. Promising potential results against SARS-CoV-2 RNA dependent RNA polymerase (RdRp) and methyltransferase (nsp16) are presented.  相似文献   

Energetic radiation produced during rocket-triggered lightning     

Dwyer JR  Uman MA  Rassoul HK  Al-Dayeh M  Caraway L  Jerauld J  Rakov VA  Jordan DM  Rambo KJ  Corbin V  Wright B 《Science (New York, N.Y.)》2003,299(5607):694-697

Using a NaI(Tl) scintillation detector designed to operate in electrically noisy environments, we observed intense bursts of energetic radiation (> 10 kiloelectron volts) during the dart leader phase of rocket-triggered lightning, just before and possibly at the very start of 31 out of the 37 return strokes measured. The bursts had typical durations of less than 100 microseconds and deposited many tens of megaelectron volts into the detector. These results provide strong evidence that the production of runaway electrons is an important process during lightning.  相似文献   

Quantifying Transport Between the Tropical and Mid-Latitude Lower Stratosphere     

CM Volk  JW Elkins  DW Fahey  RJ Salawitch  GS Dutton  JM Gilligan  MH Proffitt  M Loewenstein  JR Podolske  K Minschwaner  JJ Margitan  KR Chan 《Science (New York, N.Y.)》1996,272(5269):1763-1768

Airborne in situ observations of molecules with a wide range of lifetimes (methane, nitrous oxide, reactive nitrogen, ozone, chlorinated halocarbons, and halon-1211), used in a tropical tracer model, show that mid-latitude air is entrained into the tropical lower stratosphere within about 13.5 months; transport is faster in the reverse direction. Because exchange with the tropics is slower than global photochemical models generally assume, ozone at mid-latitudes appears to be more sensitive to elevated levels of industrial chlorine than is currently predicted. Nevertheless, about 45 percent of air in the tropical ascent region at 21 kilometers is of mid-latitude origin, implying that emissions from supersonic aircraft could reach the middle stratosphere.  相似文献   

Lead and Helium Isotope Evidence from Oceanic Basalts for a Common Deep Source of Mantle Plumes     

BB Hanan  DW Graham 《Science (New York, N.Y.)》1996,272(5264):991-995

Linear arrays in lead isotope space for mid-ocean ridge basalts (MORBs) converge on a single end-member component that has intermediate lead, strontium, and neodymium isotope ratios compared with the total database for oceanic island basalts (OIBs) and MORBs. The MORB data are consistent with the presence of a common mantle source region for OIBs that is sampled by mantle plumes. 3He/4He ratios for MORBs show both positive and negative correlation with the 206Pb/204Pb ratios, depending on the MORB suite. These data suggest that the common mantle source is located in the transition zone region. This region contains recycled, oceanic crustal protoliths that incorporated some continental lead before their subduction during the past 300 to 2000 million years.  相似文献   

Very long baseline interferometric observations made with an orbiting radio telescope     

Levy GS  Linfield RP  Ulvestad JS  Edwards CD  Jordan JF  DI Nardo SJ  Christensen CS  Preston RA  Skjerve LJ  Stavert LR  Burke BF  Whitney AR  Cappallo RJ  Rogers AE  Blaney KB  Maher MJ  Ottenhoff CH  Jauncey DL  Peters WL  Nishimura T  Hayashi T  Takano T  Yamada T  Hirabayashi H  Morimoto M  Inoue M  Shiomi T  Kawaguchi N  Kunimori H 《Science (New York, N.Y.)》1986,234(4773):187-189

An orbiting spacecraft and ground observatories have been used to obtain interferometric observations of cosmic radio sources. The Tracking and Data Relay Satellite System (TDRSS) was used as the orbiting observatory in conjunction with two 64- meter radio telescopes at ground observatories, one in Australia and one in Japan. The quasars 1730-130 (NRAO 530), 1510-089, and 1741-038 were observed at a frequency of 2.3 gigahertz, and a maximum projected baseline of 1.4 earth diameters was achieved. All quasar observations for which valid data were acquired resulted in detected fringes. Many of the techniques proposed for a dedicated very long baseline interferometry observatory in space were used successfully in this experiment.  相似文献   

Characterization of a novel coronavirus associated with severe acute respiratory syndrome     

Rota PA  Oberste MS  Monroe SS  Nix WA  Campagnoli R  Icenogle JP  Peñaranda S  Bankamp B  Maher K  Chen MH  Tong S  Tamin A  Lowe L  Frace M  DeRisi JL  Chen Q  Wang D  Erdman DD  Peret TC  Burns C  Ksiazek TG  Rollin PE  Sanchez A  Liffick S  Holloway B  Limor J  McCaustland K  Olsen-Rasmussen M  Fouchier R  Günther S  Osterhaus AD  Drosten C  Pallansch MA  Anderson LJ  Bellini WJ 《Science (New York, N.Y.)》2003,300(5624):1394-1399

In March 2003, a novel coronavirus (SARS-CoV) was discovered in association with cases of severe acute respiratory syndrome (SARS). The sequence of the complete genome of SARS-CoV was determined, and the initial characterization of the viral genome is presented in this report. The genome of SARS-CoV is 29,727 nucleotides in length and has 11 open reading frames, and its genome organization is similar to that of other coronaviruses. Phylogenetic analyses and sequence comparisons showed that SARS-CoV is not closely related to any of the previously characterized coronaviruses.  相似文献