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31.
The snake melon, Cucumis melo subsp. melo Flexuosus Group, is a cucurbit crop that was grown and esteemed in Mediterranean lands in antiquity and classical times. Images of snake melons appear in ancient Egyptian wall paintings and sculptures and in mosaics from the Roman Empire. The sikyos of Greek, the cucumis of Latin, and the qishu’im of Hebrew, thought by many to be cucumbers, Cucumis sativus, have now been identified as snake melons. Less iconographic and written evidence exists concerning the appreciation of snake melons during the medieval period. The present work focuses on some philologically based evidence of the importance of snake melons leading into and including the medieval period, with two specific objectives. One was to trace the records of the Hebrew epithet piqqus, which applied to removal of the hairs of young cucurbit fruits, and the Arabic epithet faqqous, used historically and to the present day to designate snake melons. Another objective was to re-affirm how piqqus was actually conducted, as mandated in the second-century code of Jewish Oral Law known as the Mishna. Various conjugational forms of the Hebrew word piqqus were found in writings dating from 200 CE to approximately 600 CE. Evidence is presented that further establishes the exact meaning of piqqus as the rubbing off of the hairs of young cucurbit fruits. The Arabic word faqqous was found in writings dating from the beginning of the tenth century and through to the end of the medieval period in the fifteenth century, the writers hailing from Andalusia in the west to Iraq in the east. These writings suggest that the snake melon was a familiar vegetable across a wide geographic belt throughout the medieval period.  相似文献   
32.
The identification of MHC class II-restricted antigenic peptides for inclusion into vaccines and/or as diagnostic test reagents for mycobacterial infections remains a high research priority. To expedite discovery of such peptides, numerous bioinformatic tools have been developed to predict whether a given peptide is likely to form a stable binding interaction with MHC class II molecules. However, no prediction tool dedicated to the identification of bovine MHC (BoLA) class II-restricted peptides is currently available. Using experimental immunogenicity data derived from the stimulation of whole blood of Mycobacterium bovis-infected cattle with 105 individual M. bovis-derived peptides, we have compared the ability of a novel BoLA DRB3 structure-based prediction method (Hepitom) with the human MHC class II binding predictor model ProPred in predicting peptides that induce bovine T-cell activation. When a stringent cut off for considering peptide antigenicity was applied, the sensitivities of Hepitom and ProPred in detecting immunogenic peptides were 62% and 77%, respectively. In contrast, the Hepitom model showed greater specificity, with values of 66% and 34% for Hepitom and ProPred, respectively. Using all peptides, seven out of eleven M. bovis proteins were identified as being highly immunogenic. All but one of these antigens were also identified when just the Hepitom predicted peptides were used, while only four of the seven were identified using the ProPred predicted peptides. In conclusion, we demonstrate that the Hepitom model is a useful pre-screening tool to select peptides for further immunogenicity studies in cattle without major impact on the identification of antigenic M. bovis proteins.  相似文献   
33.
Harry S. Paris 《Euphytica》2000,115(3):191-196
Alternating intense (dark) and light stripes on the fruits are a fairly common feature of Cucurbita pepo, a highly variable species encompassing various kinds of pumpkins, squash, and gourds. The intense stripes can be narrow and broken or broad and contiguous. Narrow, broken intense striping is conferred by allele l-1 St, which is dominant to allele l-1 for non-striped, lightly colored fruits and recessive to allele L-1 for non-striped, intensely colored fruits. Cocozelle-type squash often exhibit broad, contiguous intense stripes. The inheritance of this characteristic was studied by transferring it from cocozelle squash and preparing nearly isogenic lines having broad-striped, narrow-striped, and non-striped light-colored fruits. In the broad-striped near-isogenic line, the intense stripes averaged 37% wider than in its narrow-striped counterpart. The broad-striped line was crossed with the narrow-striped line, the non-striped light-colored line, and the non-striped intense-colored `Fordhook Zucchini'. Broad striping was dominant to narrow striping and to non-striped light and conferred by a single gene; it was recessive to non-striped intense. The gene for broad striping was found to be allelic to that for narrow striping and to that for non-stripe dintense and is herein assigned the symbol l-1 BSt. Dominance relationships at the l-1 locus were observed to be L-1>l-1 BSt >l-1 St >l-1. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
34.
建立了番茄动态生长的功能模型,从个体和器官的角度,研究生物量在植物体内的生产和分配规律、器官的动态生长规则。模型根据蒸腾作用计算物质的生产;根据节间、叶柄、叶片和果实等器官的汇强和扩展规律对物质进行分配;根据与物质量的动态关系计算各器官的几何尺寸;利用试验数据对模型参数进行估计。通过对参数进行比较和分析得出它们对各器官生长的影响程度和器官本身的扩展规律。并对模型输出与测量数据的拟合程度进行了残差分析,验证了模型的合理性和有效性。  相似文献   
35.
Paris  A.  Bonardi  S.  Bacci  C.  Boni  E.  Salmi  F.  Bassi  L.  Brindani  F. 《Veterinary research communications》2010,34(1):145-148

The aim of the study was to evaluate the sensitivity of two m-PCR methods for the quantitative determination of E. coli O157:H7 in foodstuffs. Genomic serotyping was carried out on bacterial cultures, and the necessary time was optimized to increase the resolution of the method. Subsequently, artificial contamination trials using meat were conducted to assess method accuracy in foodstuffs and pursue the genetic typing of pathogens. Measurement thresholds were shown to range between 105 and 106 CFU/mL, but were reduced by four logarithmic cycles in 80% of samples. Relative to the meat contamination trials, serotypes were identified after 24 hours, corresponding to 10 CFU/mL inoculum, with higher rates seen when m-TSB was used for enrichment. Inoculated samples were found to contain three virulence factors (hlyA, eaeA, and stx1).

  相似文献   
36.
Tropical Animal Health and Production - The aim was to monitor the growth, the dry mass accumulation curve, and the structural photosynthetic components of forage peanut pasture, in different...  相似文献   
37.
Wines from three important wine-producing regions, Stellenbosch, Robertson, and Swartland, in the Western Cape Province of South Africa, were analyzed by ICP-MS and the elemental composition used in multivariate statistical analysis to classify the wines according to geographical origin. The method is based on the assumption that the provenance soil is an important contributor to the trace element composition of a wine. A total of 40 elements were determined in 40 wines. Of these, 20 elements: Li, B, Mg, Al, Si, Cl, Sc, Mn, Ni, Ga, Se, Rb, Sr, Nb, Cs, Ba, La, W, Tl, and U showed differences in their means across the three areas. In a stepwise discriminant analysis procedure, functions based on linear combinations of the log-transformed element concentrations of Al, Mn, Rb, Ba, W, and Tl were generated to correctly classify wines from each region. In an alternative approach, a pairwise discriminant analysis procedure, not previously used in wine provenance studies, was tested. In this procedure, the classification was done in three steps, with each step classifying a wine as coming from a certain region or not. The combination of elements characterizing wines from a particular region was different in each region. The discriminant functions were based on the following elements: Al, Mn, Rb, Ba, and W for Stellenbosch; Se, Rb, Cs, and Tl for Robertson; and Al, Mn, Rb, Sr, Ba, and Tl for Swartland. After this procedure, the classification of the wines into one of the groups was 100% successful.  相似文献   
38.
A 4-year-old, male Jack Russell terrier was presented for a 6-month history of progressive right hemiparesis with episodic cervical hyperesthesia. The neurological examination showed a right-sided, upper motoneuron syndrome and partial Horner's syndrome. Two magnetic resonance imaging (MRI) examinations were performed 3 months apart and revealed a persistent cervical intramedullary hematoma. A dorsal myelotomy was performed. A subacute hematoma was confirmed histologically without underlying lesions. Eighteen months later, the dog's clinical signs were minimal. Two MRI examinations were performed 2 weeks and 5 months after surgery and revealed regressing signal abnormalities at the surgical site, consistent with a surgical scar.  相似文献   
39.
40.
不同光截获下番茄形态结构的动态模拟与比较   总被引:2,自引:0,他引:2  
为研究不同光截获对番茄植株形态结构的影响,基于结构-功能互反馈建模原理建立了番茄结构-功能模型。采用基于番茄拓扑结构的多目标估算方法,利用实验观测数据对模型进行多目标校准和验证。对局部遮阴和无遮阴栽培条件下番茄植株的生长过程进行动态模拟,并对不同生长阶段番茄植株的形态结构、器官周期累积生物量以及器官三维形态输出进行比较,结果表明:无遮阴栽培条件下,番茄植株茎杆节间短粗,叶片和果实较大。而局部遮阴栽培条件下番茄植株茎杆细长,叶片稀薄,果实较小。不同光截获下模型的输出结果与观测数据拟合较好,验证了模型的有效性。  相似文献   
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