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Frequency of pathology and of some anomalies in skeletons of Bedouin living about 200 BP, uncovered in the Israeli Negev, is considered in relation to particular bone, sex, age-group, and kinds of defects. The environment of the Bedouin in relation to his “health-status” is noted. Two-thirds of the skeletons had one or more different bones with defects. Incidence of crania with defects was: males, 26%; females, 18%; the highest incidence occurred at age 35–49. Alveolar abscesses occurred in 28% of maxillae, 9% of mandibles. Of the long bones, the tibia was most frequently affected (15%): swelling of the shaft, relatively common, was apparently caused by bejel, a non-venereal form of syphilis, similar to yaws, endemic to the Bedouin. Forty-eight percent had defective vertebrae, usually an arthritic manifestation of one kind or another; half of this group had defects in more than one region of the spine. Defects also occurred relatively frequently in the innominata, sacrum, scapula, and clavicle, mostly arthritic lesions except in the sacrum in which the percentage with sacral hiatus was high. Average age at death was, males, 43 years, females, 33 years (adults only), and 28 years for all ages.  相似文献   

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From 1 January 1981 to 31 December 1982 information on all births to Bedouin Arab women residing in the Negev Desert of Israel showed a previously unreported seasonal pattern. The peak season, November-February, coincided with the period of cool temperatures and the Bedouin Arab cultural seasons of winter and spring. This pattern is different from those of Jewish and Christian groups in the same region, a difference not attributable to religion alone. Sociodemographic factors associated with the peak season of birth include traditional occupations of fathers, multiparae 2+, and traditional place of residence. This pattern has persisted over the past 15 years although it is less apparent among the more recently sedentarized Bedouin Arabs.  相似文献   

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Information collected on herding practices and economic activities of nine Bedouin households is used to define livelihood strategies and examine their economic viability. Large variations found in herding practices and other means of subsistence are a response to external policies and constraints which limit herding space and sources of income. Differential access to resources and different sociocultural norms are important factors. The identification and analysis of different livelihood strategies is a useful point of departure for discussing the development of Bedouin herding in the Negev and for formulating policy that is more effective and empathetic.  相似文献   

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Escherichia coli Capsule Bacteriophages II. Morphology   总被引:14,自引:8,他引:6       下载免费PDF全文
The Escherichia coli capsule bacteriophages (K phages) described herein are specific for certain capsular strains of E. coli, all of them test strains for different E. coli K antigens. The phages are not adsorbed to the acapsular mutants of their host organisms nor to similar strains with serologically and chemically different capsular polysaccharides. Thirteen E. coli (and one Klebsiella) K phages were visualized in the electron microscope. Most viruses are similar to P22 and thus belong to Bradley group C; however, one each of group A (long, contractile tail) and group B (long, noncontractile tail) was also found. All K phages were seen to carry spikes but no tail fibers were detected. These results suggest that the structures responsible for the recognition of the thick (about 400 nm or more) capsular polysaccharide gels are located in these spikes.  相似文献   

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Structure of adenovirus fibre. II. Morphology of single fibres   总被引:8,自引:0,他引:8  
Adenovirus type 2 fibres in crystals appear to be significantly longer than found previously (accompanying paper). We therefore examined isolated fibre by electron microscopy and measured a length of 370 A, consistent with the length found in the crystals. The specific N-terminal structure of the fibre caused a heterogeneity in the length that may at least partially explain the values of 280 to 310 A published previously. Green et al. described a 15 amino acid repeat in the primary structure of the shaft of the fibre thought to be associated with the specific three-dimensional folding of the shaft. We compared the adenovirus type 2 (with 22 repeats) and type 3 (with 6 repeats) fibre lengths and derived a contribution of 13.2 A to the length of the shaft per 15 amino acid repeat. Specific morphological features of the fibre are discussed in relation to its amino acid sequence.  相似文献   

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Although much morphometric overlap occurs among five geographical isolates of Heterodera glycines in Indiana, significant differences in means exist among the isolates for various comparisons of second-stage juveniles. By using combinations of means, most of the isolates can be distinguished from the rest: e.g., the Vanderburgh County isolate (southern Indiana) has the longest esophagus, tail, and tail terminus; the Vigo County isolate (also from the south) has the shortest esophagus; the White County isolate (northern Indiana) has the shortest tail and tail terminus and the greatest total length; the Benton County isolate (north) is the shortest. Morphological similarities and differences do not appear to be coordinated with reproductive behavioral patterns we observed in the northern versus the southern isolates.  相似文献   

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Factor analysis was used to identify the processes responsible for the changes in water quality in a stratified wastewater reservoir. These reservoirs are well suited to study hypertrophic conditions. In the epilimnion, the main source of variablility was the external loading due to variations in wastewater inputs and water level (volume) of the reservoir. The second source was the seasonal climatic changes affecting photosynthesis. The third source was differences between night and day processes affecting REDOX potential. In the hypolimnion, the main source of variability was organic loading but due to both external loading (wastewater inputs) and internal loading (compounds released from the sediments). The second source was related to the input of chlorophyll into the hypolimnion, which were external (entry of chlorophyll rich inflow from a waste stabilization pond) and/or internal (input of chlorophyll from upper layers due to water column mixing).  相似文献   

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Background

Developmental instability of shelled gastropods is measured as deviations from a perfect equiangular (logarithmic) spiral. We studied six species of gastropods at ‘Evolution Canyons I and II’ in Carmel and the Galilee Mountains, Israel, respectively. The xeric, south-facing, ‘African’ slopes and the mesic, north-facing, ‘European’ slopes have dramatically different microclimates and plant communities. Moreover, ‘Evolution Canyon II’ receives more rainfall than ‘Evolution Canyon I.’

Methodology/Principal Findings

We examined fluctuating asymmetry, rate of whorl expansion, shell height, and number of rotations of the body suture in six species of terrestrial snails from the two ‘Evolution Canyons.’ The xeric ‘African’ slope should be more stressful to land snails than the ‘European’ slope, and ‘Evolution Canyon I’ should be more stressful than ‘Evolution Canyon II.’ Only Eopolita protensa jebusitica showed marginally significant differences in fluctuating helical asymmetry between the two slopes. Contrary to expectations, asymmetry was marginally greater on the ‘European’ slope. Shells of Levantina spiriplana caesareana at ‘Evolution Canyon I,’ were smaller and more asymmetric than those at ‘Evolution Canyon II.’ Moreover, shell height and number of rotations of the suture were greater on the north-facing slopes of both canyons.

Conclusions/Significance

Our data is consistent with a trade-off between drought resistance and thermoregulation in snails; Levantina was significantly smaller on the ‘African’ slope, for increasing surface area and thermoregulation, while Eopolita was larger on the ‘African’ slope, for reducing water evaporation. In addition, ‘Evolution Canyon I’ was more stressful than Evolution Canyon II’ for Levantina.  相似文献   

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Liberian Negro deciduous dentitions have arch dimensions which significantly exceed those of a variety of White populations. Winged incisors were present in 14.3% of the Negro population, again exceeding White values. No differences were noted in incisal overbite or overjet. Diastemal spaces were greater in the Negro dentitions than in the White, but the significance of this is as yet unknown. An exceptional finding was the absolute lack of Class II (distocclusion) in the Negro series. A discussion of functional occlusion stressed the necessity for the inclusion of such dynamic factors as dental abrasion, mesial migration and physiological rest position in future studies of comparative dental anthropology.  相似文献   

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