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1.
George Paul Meiu 《Ethnos》2015,80(4):472-496
ABSTRACT

In the 1980s, Samburu men from northern Kenya began migrating to coastal tourist resorts to sell souvenirs and perform traditional dances for European tourists. Many of them engaged in transactional sex or marriages with European women attracted to the image of the exotic African young male warrior. Through relationships with European women, some Samburu men managed to rapidly accumulate wealth, becoming so-called ‘young big-men’. As a way to transform their wealth into more durable forms of respectability, these men used their money to marry local women and speed up their ritual initiation into elderhood. Meanwhile, there also emerged the figure of ‘beach-boy elders’, men who aged before accumulating sufficient wealth. They returned to coastal tourist resorts, dressed as young warriors, and waited to find European partners. In the article, I argue that beach-boy elders and young big-men produce queer moments in the temporalities of ageing, in that they subvert normative expectations of ageing at the very same time that they seek to produce them.  相似文献   

2.
Several isolated cheek teeth and mandibular specimens of Rhinocerotidae (Mammalia, Perissodactyla) from the upper Miocene Namurungule Formation in Samburu Hills, Kenya, are redescribed. Previously, these specimens had been identified as Chilotheridium pattersoni, Chilotheridium sp., Paradiceros mukirii, and Paradiceros sp. They are reidentified here as documenting the genus Brachypotherium based on their bucco-lingually broad molariform upper premolars with short crochet and flattened buccal walls on both upper and lower molars, the latter having a shallow external groove. Comparisons with other Brachypotherium species suggest that the present specimens belong to Brachypotherium sp. cf. B. minor. The presence of Brachypotherium in the Samburu Hills, at ca. 9.5 Ma, is concordant with the paleoenvironment (presence of lacustrine and river environments) known for this locality during the early late Miocene.  相似文献   

3.
Antique Venetian trade beads used in Samburu women's marriage necklaces ( mporo ) have recently undergone intense recommodif ication in the transnational trade bead market concurrent with their appropriation by Euro-American women in both religious and secular domains. The article offers duai ethnographies of this mporo bead in order to advance anthropological understandings of precious objects in the context of globalization. Samburu and Euro-American desires for the "same" bead have been both reciprocal and distinct: Whereas Samburu desires for and exchange of mporo beads have been rooted in Samburu cultural forms, Euro-American desires for the same bead are linked to a kind of "fictional inalienability" that is not embedded in Samburu social relations but is instead rich in spiritual associations imagined through Euro-American women's vague understandings of the bead's "original" African owners. [Keywords: material culture, globalization, United States, Kenya, pastoralists]  相似文献   

4.
Male-centred aspects of political behaviour have generally remained the explanatory and interpretive focuses in analyses of the social organization of African pastoralists. While recent work on African pastoralists has shed increasing light on the lives of women, I argue that key assumptions underlying anthropological models of male dominance in these societies have been insufficiently challenged. Drawing on recent approaches in gender and social organization that highlight the mutual constitution of domestic and political domains, I examine comparative material from two well-known pastoralist societies: the Samburu of northern Kenya and the Nuer of southern Sudan. In doing so, I suggest strong linkages between male-dominated 'political spheres' and areas of domestic life in which the role of women is more significant – particularly processes of domestic food distribution. In re-examining central facets of Samburu politics – which are best known through Paul Spencer's seminal analysis of the gerontocratic aspects of Samburu political life – I suggest that the status and identities of Samburu men are in fundamental ways defined through their relationship to women as providers of food within Samburu households. Comparative material from the Nuer suggests, additionally, the strategic use of food by women in influencing male 'political spheres'. In comparing these cases, I suggest a more general model through which domestic processes of food allocation as realms of female-centred social action may be seen to play a central role in the forms and processes of pastoral 'political' life.  相似文献   

5.
BackgroundThe physio-chemical properties of blood contacting biomaterials play an important role in determining their hemocompatibility. It is shown in literature that surface roughness and porosity have significant effect on hemocompatibility. In this study, we use a biocompatible, low thrombogenic nanocomposite polymer called POSS-PCU to test this hypothesis: would porosity compromise the hemocompatibility of POSS-PCU. We compared the hemocompatibility of POSS-PCU films of various pore sizes with PTFE, which is a commercially available material used in most blood contacting devices.MethodsSterilized POSS-PCU films with different size pores were prepared as samples and porous PTFE film were selected as control. And all samples were subjected to SEM for topograpgy, mechanical test for characterization and hemocompatibility tests to evaluate contact activation, platelet adhesion and activation, as well as whole blood clotting response to the samples.ResultsWCA significantly increased with the pore size of POSS-PCU film, whereas both tensile stress and strain decreased significantly as the sizes of pores increased. However, when compared to PTFE film with same size pores, POSS-PCU films showed both higher tensile stress and strain. Pore size had little impact over POSS-PCU's surface chemistry groups as tested by FTIR analysis. Contact activation and platelet adhesion essay also showed no significant difference between different POSS-PCU samples. However, in whole blood reactions, POSS-PCU with pores size around 2–5 μm showed higher BCI than plain films and those with pores size around 35–45 μm. POSS-PCU showed lower thrombogencity and higher hemocompatibility comparing with porous PTFE on the aspects of platelet activation, adhesion and whole blood reaction.Summary and conclusionsPOSS-PCU polymer films as a biomaterial in chronic blood contacting implants show significant lower thrombogencity and higher hemocompatibility than porous PTFE film. It is desirable as a coating or covering material in small diameter stents for treating cardiovascular diseases, cerebral vascular diseases and peripheral arterial diseases.  相似文献   

6.
PurposeTo evaluate EBT3 for pre-treatment patient specific quality assurance (QA). The method we propose combines the experience gained in our center with the guidelines of the protocol proposed by Lewis et al. in 2012. To compare the multichannel approach with the single channel dosimetry.MethodsGafchromic® EBT3 films were irradiated both at linac and TomoTherapy and calibration curves were obtained. A series of irradiations with simple fields (uniform dose distributions on regular shaped targets) was performed. In a second stage, films were exposed to full clinical plans at linac (step and shoot IMRT and VMAT). At TomoTherapy dose maps were obtained for a clinical plan in three different coronal planes. Films were digitized using an Epson 10000XL scanner and FilmQA™ Pro software was employed for the analysis.ResultsThe measured calibration curves suggest that, at least for the two beams taken into account (6 MV linac and TomoTherapy), a single calibration can be successfully adopted for each film lot. The application of the multichannel optimization method strongly improves the results in terms of gamma passing rates of the comparison between measured and calculated maps.ConclusionsUp to now EBT films, although attractive, were not preferred for routine patient specific QA due to their complex and time consuming processing and to the challenging work of characterization. The application of the mentioned protocol, together with some additional precautions, and the adoption of the multichannel optimization dosimetry, make this detector a handy and reliable tool for patient specific QA.  相似文献   

7.
We describe and illustrate Coccinia pwaniensis Holstein from eastern Tanzania and southeast Kenya, and C. samburuensis Holstein from the Samburu area in Kenya. The new species were already recognised by Charles Jeffrey in 1967 and are now known from eight and four collections, respectively. Ongoing monographic work also revealed three new synonyms and the need for a new combination, Coccinia heterophylla (Hook. f.) Holstein.  相似文献   

8.
PurposeA method of calibrating radiochromic films for Gamma Knife® (GK) dosimetry was developed. The applicability and accuracy of the new method were examined.MethodsThe dose distribution for a sixteen millimeter single-shot from a GK was built using a reference film that was calibrated using the conventional multi-film calibration (MFC) method. Another film, the test film, from a different set of films was irradiated under the same conditions as the reference film. The calibration curve for the second set of films was obtained by assigning the dose distribution of the reference film to the optical density of the test film, point by point. To assess the accuracy of this single-film calibration (SFC) method, differences between gamma index pass rates (GIPRs) were calculated.ResultsThe SFC curves were successfully obtained with estimated errors of 1.46%. GIPRs obtained with the SFC method for films irradiated using a single-shot showed differences less than one percentage point when dose difference criterion (ΔD) was 2% and the distance to agreement criterion (Δd) was 1 mm. The GIPRs of the SFC method when the films were irradiated following a virtual target treatment plan were consistent with the GIPRs of the MFC method, with differences of less than 0.2 percentage points for ΔD = 1% and Δd = 1 mm.ConclusionThe accuracy of the SFC method is comparable to that of conventional multi-film calibration method for GK film dosimetry.  相似文献   

9.
AimTo determine the energy and dose dependence of GafChromic EBT3-V3 film over an energy range 0.2 mm Al HVL to 6 MV.BackgroundThe decay scheme of a brachytherapy source may be complex and the spectrum of energy can be wide. LiF TLDs are the golden standard recommended for dosimetric measures in brachytherapy, for their energy independence, but TLDs could be not available in some centres. An alternative way to perform dose measurements is to use GafChromic films, but they show energy dependence.Methods and materialsFilms have been irradiated at increasing dose with three different beams: 6 MV beam, TPR20, 10 = (0.684 ± 0.01), HVL = (2.00 ± 0.01)mmAl and HVL = (0.20 ± 0.01)mmAl. Calibration curves were generated using the same dose range (0cGy to 850cGy) for the three energies. Using the 6 MV calibration curve as reference, the film response in terms of net optical density (OD) was evaluated.ResultsThe difference in the calibration curve obtained by irradiating the film with 6 MV and 2 mm Al HVL energy beams is less than 3 %, within the calibration uncertainty, in the dose range 500-850cGy. The OD of EBT3-V3 film is significantly lower at 0.2 mmAl HVL compared to 6 MV, showing differences up to 25 %.ConclusionWithin the range 6 MV-2 mm Al HVL and dose higher than 500cGy, GafChromic EBT3-V3 films are energy independent. In this dose range, films can be calibrated in a simple geometry, using a 6 MV Linac beam, and can be used for brachytherapy sources dose measures. The use of EBT3 films can be extended to reference dosimetry in Ir-192 clinical brachytherapy.  相似文献   

10.
AimBlood irradiators (BI) initial acceptance testing and routine annual dosimetry checks require radiation dose measurements in order to comply with regulatory requirements.BackgroundTraditionally thermo-luminescence dosimeters (TLD) have been used to measure the dose. The EBT3 film is reported to be a better dosimeter for low energy X-rays than its predecessors EBT2 and EBT. To the best of our knowledge, the use of EBT3 films to perform dosimetry on X-ray based BI has not been reported yet.Materials and methodsWe performed routine radiation dosimetry checks using EBT3 films on a new X-ray based BI and compared the results with TLD dosimetry. Calibration films were irradiated with radiation beam from a Co-60 Gamma Knife (GK) radiosurgery machine and, alternatively, using an Ir-192 high dose rate (HDR) brachytherapy device. The films were calibrated to cover a wide dose range from 1 to 40 Gy. Such a wide dose range has not been reported yet in BI film dosimetry.ResultsWe obtained a relative difference of about 6.6% between doses measured using TLD and those measured using EBT3 films. Both irradiation methods using GK or HDR were found to be adequate for the calibration of the EBT3 Gafchromic films.ConclusionsWe recommend the use of EBT3 films in routine X-ray based BI dosimetry checks. The presented method takes advantage of available radiotherapy equipment that can be efficiently used for EBT3 films calibration. The method is fast, reproducible and saves valuable medical physicist's time.  相似文献   

11.
Jon  Holtzman 《American anthropologist》2001,103(4):1041-1058
In recent years, many Samburu women have begun to brew beer and liquor for sale to elders—including their own husbands. Drawing on "cooperative conflict" approaches to domestic processes, the essay examines brewing in reference to the economic and cultural position of men and women within Samburu households and society at large. Focusing in particular on the issues posed to each gender by the differential control of key resources by the other—food by women and cash by men—the essay views brewing as a negotiated structure through which men and women address the particular gender-based problems they encounter in daily life. [ gender, family, brewing, Africa ]  相似文献   

12.

Background

The Samburu region of northern Kenya is undergoing significant change, driven by factors including greater value on formal education, improvements in infrastructure and development, a shift from community to private ownership of land, increased sedentary lifestyles and global climate change. One outcome of these changes are an increasingly greater likelihood for adolescent boys to be enrolled in school rather than herding livestock on behalf of the family in a landscape shared with numerous native vegetation and wildlife species.

Methods

This study compared identification and knowledge of native plant species between boys enrolled in school with boys of similar age but primary responsibility as herders, called moran. Study participants walked an approximately 100 m path with 10 flagged points in which they were asked to identify any plant species at that point and associated facts of each species, within a 1 m radius.

Results

On average, moran identified 38 species compared to 20 for students, including nearly 13 (of a possible 15) species considered to have high cultural significance. Students identified an average of 8.6 culturally-significant plants. Further, moran shared nearly 18 correct facts about the plants, compared with ten for students. In addition, herding frequency was the only significant predictor of plant identification in a linear regression.

Conclusion

The results demonstrate that while formal education undoubtedly provides benefits to students, attendance in school in lieu of the traditional role of herders has consequences on young men in Samburu related to ability to identify native and culturally-significant plants. This further shows the importance for communities like those in Samburu undergoing change need to develop alternative options to transmit local traditional knowledge to its younger generations.
  相似文献   

13.
PurposeThe aim of this study is to report results of measurements of dose to the skin in vivo with radiochromic EBT films in treatments with helical tomotherapy.Methods and materialsIn vivo measurements were performed by applying pieces of radiochromic films to the skin or to the inner side of thermoplastic mask before the treatment. The sites of treatment included scalp, brain, head and neck, cranio-spinal axis and lower limbs. Skin dosimetry was performed in a patient who experienced grade 3–4 acute side effects to the skin shortly after the first treatment sessions. For each patient we measured the setup errors using the daily MVCT acquired for image guidance of the treatment. EBT films were read with a flatbed Epson Expression scanner and images were processed with an in-house written routine.ResultsA total of 96 measurements of dose to the skin performed on 14 patients. The mean difference and standard error of the mean difference between measured and TPS-calculated dose was ?9.2% ± 2.6% for all treatments, ?6.6% ± 2.6% for head and neck treatments. These differences were statistically significant at the 0.05 significance level (t-Student test). Planned dose and dose range in the region of measurements were not correlated with dose discrepancy.ConclusionsRadiochromic EBT films are suitable detectors for surface dose measurements in tomotherapy treatments. Results show that TPS overestimates dose to the skin measured with EBT radiochromic films. In vivo skin measurements with EBT films are a useful tool for quality assurance of tomotherapy treatments, as the treatment planning system may not give accurate dose values at the surface.  相似文献   

14.
An anthrax outbreak occurred in the Wamba area of southern Samburu, Kenya, between December 2005 and March 2006. The outbreak affected equids including the endangered Grevy's zebras (Equus grevyi), plain zebras (Equis Burchelli) and donkeys (Equus asinus). Most of the deaths were localized in Nkaroni area just west of Wamba town. The diagnosis of anthrax was rapidly confirmed by bacteriological methods. The relevant government departments, including the Kenya Wildlife Service and Veterinary Department, and other stakeholders were promptly informed. Fifty‐three Grevy's zebra and 26 plains zebras died from anthrax. An equal number (eighteen) of adult male and female Grevy's zebras succumbed to the disease. The outbreak affected immature and mature individuals equally. The dead plain zebras included fifteen adult females, two adult males and nine immature individuals. The Veterinary Department responded by vaccinating livestock while Kenya Wildlife Service vaccinated 620 Grevy's zebras within southern Samburu. Examination of sites at which carcasses of animals which succumbed to the disease were burnt, revealed that unsupervised burning did not eliminate anthrax spores in 42% of the cases (n = 14). There is an urgent need to incorporate strategic wildlife disease monitoring in the struggle to save Grevy's zebras and other endangered species.  相似文献   

15.
PurposePoint detectors are frequently used to measure patient's maximum skin dose (MSD) in fluoroscopically-guided interventional procedures (IP). However, their performance and ability to detect the actual MSD are rarely evaluated. The present study investigates the sampling uncertainty associated with the use of grids of point detectors to measure MSD in IP.MethodChemoembolisation of the liver (CE), percutaneous coronary intervention (PCI) and neuroembolisation (NE) procedures were studied. Spatial dose distributions were measured with XR-RV3 Gafchromic® films for 176 procedures. These distributions were used to simulate measurements performed using grids of detectors such as thermoluminescence detectors, with detector spacing from 1.4 up to 10 cm.ResultsThe sampling uncertainty was the highest in PCI and NE procedures. With 40 detectors covering the film area (36 cm × 44 cm), the maximum dose would be on average 86% and 63% of the MSD measured with Gafchromic® films in CE and PCI procedures, respectively. In NE procedures, with 27 detectors covering the film area (14 cm × 35 cm), the maximum dose measured would be on average 82% of the MSD obtained with the Gafchromic® films.ConclusionThermoluminescence detectors show good energy and dose response in clinical beam qualities. However the poor spatial resolution of such point-like dosimeters may far outweigh their good dosimetric properties. The uncertainty from the sampling procedure should be estimated when point detectors are used in IP because it may lead to strong underestimation of the MSD.  相似文献   

16.
Purposes: To assess performance of FilmQA Pro software for pre-treatment patient-specific quality assurance (QA), using radiochromic films and two commercial flatbed scanners. To evaluate a novel multichannel approach compared to the classical red channel evaluation.Material and methodsPatient films (mostly EBT2 films, one box of EBT3) were digitalized using successively two flatbed scanners: the A4-size Epson V750 and the A3-size Epson 10000XL. Prior to patient dose verification, basic characteristics of films and scanners were investigated. Patient films were analyzed using FilmQA Pro software, which enables to use the signal from all three colour channels (Red, Green, Blue).ResultsCompared to the red channel evaluation, multichannel evaluation presents better passing rates with regard to local gamma index. As expected, we obtained better results using A3-size scanner compared to A4-size scanner, especially when considering large region of interest. An observation of great interest was made for both scanners: after intensive use, a tilting in the blue transmittance profiles appeared in the lamp direction, making multichannel analysis unsuitable for accurate dose evaluation.  相似文献   

17.
PurposeThe purpose of this study was to compare the delivered dose to the expected intraoperative radiation therapy (IORT) dose with in vivo dosimetry. For IORT using electrons in accelerated partial breast irradiation, this is especially relevant since a high dose is delivered in a single fraction.MethodsFor 47 of breast cancer patients, in vivo dosimetry was performed with MOSFETs and/or GAFCHROMIC EBT2 films. A total dose of 23.33 Gy at dmax was given directly after completing the lumpectomy procedure with electron beams generated with an IORT dedicated mobile accelerator. A protection disk was used to shield the thoracic wall.ResultsThe results of in vivo MOSFET dosimetry for 27 patients and GAFROMIC film dosimetry for 20 patients were analysed. The entry dose for the breast tissue, measured with MOSFETs, (mean value 22.3 Gy, SD 3.4%) agreed within 1.7% with the expected dose (mean value 21.9 Gy). The dose in breast tissue, measured with GAFCHROMIC films (mean value 23.50 Gy) was on average within 0.7% (SD = 3.7%, range −5.5% to 5.6%) of the prescribed dose of 23.33 Gy.ConclusionsThe dose measured with MOSFETs and GAFROMIC EBT2 films agreed well with the expected dose. For both methods, the dose to the thoracic wall, lungs and heart for left sided patents was lower than 2.5 Gy even when 12 MeV was applied. The positioning time of GAFCHROMIC films is negligible and based on our results we recommend its use as a standard tool for patient quality assurance during breast cancer IORT.  相似文献   

18.
ObjectiveTo explore consultants'' and general practitioners'' perceptions of the factors that influence their decisions to introduce new drugs into their clinical practice.DesignQualitative study using semistructured interviews. Monitoring of hospital and general practice prescribing data for eight new drugs.SettingTeaching hospital and nearby general hospital plus general practices in Birmingham.Participants38 consultants and 56 general practitioners who regularly referred to the teaching hospital.ResultsConsultants usually prescribed new drugs only in their specialty, used few new drugs, and used scientific evidence to inform their decisions. General practitioners generally prescribed more new drugs and for a wider range of conditions, but their approach varied considerably both between general practitioners and between drugs for the same general practitioner. Drug company representatives were an important source of information for general practitioners. Prescribing data were consistent with statements made by respondents.ConclusionsThe factors influencing the introduction of new drugs, particularly in primary care, are more multiple and complex than suggested by early theories of drug innovation. Early experience of using a new drug seems to strongly influence future use.

What is already known on this topic

UK studies show that use of new drugs by general practitioners is influenced by consultants, the nature of the drug, and perceived risk

What this study adds

Consultants generally introduced fewer drugs than general practitioners, usually within their specialtyDecisions were said to be based mainly on the evidence from the scientific literature and meetingsGeneral practitioners prescribed more new drugs and the basis of decisions was more variedDoctors'' interpretations of using a new drug were not consistent  相似文献   

19.

The study of ethnographic film has turned to the study of indigenous productions, primarily nonfictional videos made by native persons for internal and external consumption. This study was prompted by the need to locate alternate ways of seeing that Nonwestern peoples may have. This paper suggests that it is important to study local genius by studying their fictional films as well, and suggests that newness may not be found at first encounter but later after native groups domesticate foreign technology and make it their own tool. In citing this, the paper describes the various genres of films within contemporary Gujarati cinema and how the hybridity of its present forms has been procured from several sources that make for a distinctiveness which underlines emergent creative social forces at play.  相似文献   

20.
Social structure is proposed to influence the transmission of both directly and environmentally transmitted infectious agents. However in natural populations, many other factors also influence transmission, including variation in individual susceptibility and aspects of the environment that promote or inhibit exposure to infection. We used a population genetic approach to investigate the effects of social structure, environment, and host traits on the transmission of Escherichia coli infecting two populations of wild elephants: one in Amboseli National Park and another in Samburu National Reserve, Kenya. If E. coli transmission is strongly influenced by elephant social structure, E. coli infecting elephants from the same social group should be genetically more similar than E. coli sampled from members of different social groups. However, we found no support for this prediction. Instead, E. coli was panmictic across social groups, and transmission patterns were largely dominated by habitat and host traits. For instance, habitat overlap between elephant social groups predicted E. coli genetic similarity, but only in the relatively drier habitat of Samburu, and not in Amboseli, where the habitat contains large, permanent swamps. In terms of host traits, adult males were infected with more diverse haplotypes, and males were slightly more likely to harbor strains with higher pathogenic potential, as compared to adult females. In addition, elephants from similar birth cohorts were infected with genetically more similar E. coli than elephants more disparate in age. This age-structured transmission may be driven by temporal shifts in genetic structure of E. coli in the environment and the effects of age on bacterial colonization. Together, our results support the idea that, in elephants, social structure often will not exhibit strong effects on the transmission of generalist, fecal-oral transmitted bacteria. We discuss our results in the context of social, environmental, and host-related factors that influence transmission patterns.  相似文献   

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