The artificial production of translucent streaks on egg shells and various factors influencing their development     

C. Tyler  N. Standen 《British poultry science》1969,10(4):359-369

It is well known that translucent streaks can develop on egg shells due to damage to the surface of the shell. These “artifacts” have been produced under standard conditions and a study of them shows that the rate of development of the translucent areas up to their maximum brightness as measured by a scoring system can be expressed in simple mathematical terms. Having established this it was then possible to show that the rate of development of these translucent areas was (a) inversely related to the time of marking after the egg was laid, (b) directly proportional to external temperature and (c) affected by relative humidity so that a humidity between 10 and 30 per cent gave the maximum rate of development.

Replacing the egg content with water or alcohol gave some interesting results.

It was also found that the translucent streaks were weaker than corresponding opaque areas of the shell. The width of the streak produced under standard conditions varied greatly between the different eggs.

The reasons for these various findings are discussed.  相似文献   

Determination of nitrogen and protein content of meat and meat products     

R C Benedict 《Journal of the Association of Official Analytical Chemists》1987,70(1):69-74

Chemical and instrumental methods for determination of nitrogen and protein are reviewed for their mode of action and utility in analysis of meat proteins and products. Although the Kjeldahl digestion method is satisfactory for determining total nitrogen, it is imprecise for determining total protein content. Presence of variable amounts of nonprotein nitrogenous components and of connective tissue proteins such as collagen and elastin produces error if the formula (N X 6.25) is used to calculate crude protein. Such fibrous proteins have higher nitrogen levels (over 18%) than other muscle proteins (about 16%), and a higher than actual protein value will be determined unless a lower conversion factor is used to correct for their content. To determine meat protein content more accurately, a combination of Kjeldahl determination with one or more additional tests to correct for nonprotein and fibrous protein content is recommended. The choice of the additional method(s) is based on the user's requirement for protein characterization, available time, type of meat product, and sample size.  相似文献   

Structural evidence for the authenticity of the human retinoblastoma gene   总被引：87，自引：0，他引：87  

Y K Fung  A L Murphree  A T'Ang  J Qian  S H Hinrichs  W F Benedict 《Science (New York, N.Y.)》1987,236(4809):1657-1661

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ANOTHER STATE PARK NEEDED     

Benedict RC 《Science (New York, N.Y.)》1915,41(1066):827-828

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SURFACE-COLLECTING ON THE ALBATROSS     

Benedict JE 《Science (New York, N.Y.)》1886,7(165):300-301

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Demonstrating decline of an iconic species under sustained indigenous harvest – The pig-nosed turtle (Carettochelys insculpta) in Papua New Guinea     

Carla C. Eisemberg  Mark Rose  Benedict Yaru  Arthur Georges 《Biological conservation》2011,144(9):2282-2288

Papua New Guinea has astonishing biological and cultural diversity which, coupled with a strong community reliance on the land and its biota for subsistence, add complexity to monitoring and conservation and in particular, the demonstration of declines in wildlife populations. Many species of concern are long-lived which provides additional challenges for conservation. We provide, for the first time, concrete evidence of a substantive decline in populations of the pig-nosed turtle (Carettochelys insculpta); an important source of protein for local communities. Our study combined matched village and market surveys separated by 30 years, trends in nesting female size, and assessment of levels and efficacy of harvest, each of which was an essential ingredient to making a definitive assessment of population trends. Opportunities for an effective response by local communities to these declines needs to consider both conservation and fisheries perspectives because local communities consider the turtle a food resource, whereas the broader global community views it as a high priority for conservation. Our study in the Kikori region is representative of harvest regimes in most rivers within the range of the species in Papua New Guinea, and provides lessons for conservation of many other wildlife species subject to harvest.  相似文献   

Cloning and expression of desoxyhemigossypol-6-O-methyltransferase from cotton (Gossypium barbadense)     

Liu J  Benedict CR  Stipanovic RD  Magill CW  Bell AA 《Journal of agricultural and food chemistry》2002,50(11):3165-3172

Terpenoids play an important role in defense against insects and pathogens in cotton. These terpenoids contain phenolic groups. Metabolites in which the phenolic group has been converted to a methoxy group are less toxic to most insects and pathogens and thus may alter resistance. Here is reported the cloning of a gene from Gossypium barbadense that encodes the enzyme that methylates the phenolic group of desoxyhemigossypol (dHG) exclusively at the 6-position, dHG-6-O-methyltransferase (dHG-6-OMT). Partial peptide sequences from digests of purified dHG-6-OMT were used to design primers for RT-PCR amplification of cDNA fragments from poly(A) mRNA. Fragments were extended to full length using 5' and 3' RACE. The resulting cDNA codes for a 365-residue polypeptide with a calculated molecular weight of 40.6 kDa, in agreement with the molecular mass of purified dHG-6-OMT. When expressed in Escherichia coli, the bacterial lysates showed a high specificity for the methylation of desoxyhemigossypol, differentiating the cloned gene from other pathogen-induced methyltransferases.  相似文献   

A plant miRNA contributes to antibacterial resistance by repressing auxin signaling   总被引：1，自引：0，他引：1  

Navarro L  Dunoyer P  Jay F  Arnold B  Dharmasiri N  Estelle M  Voinnet O  Jones JD 《Science (New York, N.Y.)》2006,312(5772):436-439

Plants and animals activate defenses after perceiving pathogen-associated molecular patterns (PAMPs) such as bacterial flagellin. In Arabidopsis, perception of flagellin increases resistance to the bacterium Pseudomonas syringae, although the molecular mechanisms involved remain elusive. Here, we show that a flagellin-derived peptide induces a plant microRNA (miRNA) that negatively regulates messenger RNAs for the F-box auxin receptors TIR1, AFB2, and AFB3. Repression of auxin signaling restricts P. syringae growth, implicating auxin in disease susceptibility and miRNA-mediated suppression of auxin signaling in resistance.  相似文献   

Metrics for quantifying antimicrobial use in beef feedlots     

Katharine M. Benedict  Sheryl P. Gow  Richard J. Reid-Smith  Calvin W. Booker  Paul S. Morley 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(8):841-848

Accurate antimicrobial drug use data are needed to enlighten discussions regarding the impact of antimicrobial drug use in agriculture. The primary objective of this study was to investigate the perceived accuracy and clarity of different methods for reporting antimicrobial drug use information collected regarding beef feedlots. Producers, veterinarians, industry representatives, public health officials, and other knowledgeable beef industry leaders were invited to complete a web-based survey. A total of 156 participants in 33 US states, 4 Canadian provinces, and 8 other countries completed the survey. No single metric was considered universally optimal for all use circumstances or for all audiences. To effectively communicate antimicrobial drug use data, evaluation of the target audience is critical to presenting the information. Metrics that are most accurate need to be carefully and repeatedly explained to the audience.  相似文献   

Plasma D‐Dimer Concentrations during Experimental EHV‐1 Infection of Horses     

L.S. Goehring  G. Soboll Hussey  M. Gomez Diez  K. Benedict  L.K. Maxwell  P.S. Morley  M.M. Sloet van Oldruitenborgh‐Oosterbaan  D.P. Lunn 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2013,27(6):1535-1542

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