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1.
《Plains anthropologist》2013,58(99):23-31
Abstract

Archaeological reconnaissance in the valley of the Red River of the North indicates a heavy utilization of this area by Late Woodland peoples, especially manufacturers of Sandy Lake pottery. Artifact style, raw materials procurement, and the general pattern of northern Plains trade suggest the Red River area was integrated into a larger reticulum joining the northern Midwest woodlands with the northern Plains. Referring to this region as a “periphery” is acceptable only in a geographic sense, not a cultural-historical sense.  相似文献   

2.
《Plains anthropologist》2013,58(75):37-49
Abstract

The study of ceramics in the northwestern Plains has lagged since Wissler included “the lack of pottery” as one of the core Plains traits. In recent years, however, the poor development in ceramic studies is due to the lack of reported sites rather than a real void. The first part of this paper describes the Dune Buggy site and its large ceramic collection. In the second part, the pottery is identified as belonging to a non-Middle Missouri tradition and related to sites in northeastern Montana, southeastern Saskatchewan southwestern Manitoba and northwestern North Dakota. The combinations of profile, designs, and decoration appear to be heterogeneous, and an analogy is drawn to the historic period for the area to suggest an explanation for the apparent mixing. Specific problems include the lack of absolute dates and stratigraphic relationships, unpublished data, and potentially mixed components.  相似文献   

3.
《Plains anthropologist》2013,58(73):207-211
Abstract

Among the most common surface indicators of archaeological sites in south central Montana and northern Wyoming are the grey and red porcellanite flakes resulting from tool making activities. Although one of the major lithic materials used by prehistoric inhabitants of the northern plains region, porcellanite’s identity has remained relatively unknown. Amateur and professional archaeologist alike have loosely referred to this material as “metamorphosed siltstone”, “baked shale”, “Powder River chert”, “grey chert”, “fired brick”, “jasper”, etc. Similarly, fused glass is often misrepresented as obsidian. Because of its unique origin, definablearea of occurrence (the western coal region, the European coal fields, and perhaps other coalbearing areas), and its extensive utilization by the prehistoric populations of the region, porcellanite and fused glass deserve additional attention from archaeologists.  相似文献   

4.
Abstract

One of the primary characteristics distinguishing prokaryotic from eukaryotic cells is the absence of a nucleus with a clearly defined nuclear membrane. In prokaryotic cells the DNA is condensed into a structure called the nucleoid. This structure has also been referred to attimes as the nuclear body, prokaryotic nucleus, bacterial chromosome, folded genome, or folded bacterial chromosome. The nomenclature sometimes becomes confusing because unfolded bacterial DNA free of other components of the nucleoid has also been referred to as the bacterial chromosome. To avoid such confusion, it would be preferable to reserve the terms nucleoid or bacterial chromosome to describe the condensed prokaryotic DNA structures which have some features analogous to the eukaryotic metaphase chromosome and condensed interphase chromatin. If this convention is followed, the terms “folded chromosome” or “folded genome” become ambiguous because they could equally mean “folded nucleoid.” These latter terms will, therefore, be avoided throughout this article.  相似文献   

5.
Fossil samaras referred to the extant rutaceous genus Ptelea L. comprise an artificial collection of five distinct taxa with convergent fruit morphologies. Critical reexamination of these fossils revealed that only one of the five samara types can be referred to Ptelea. Two of the forms can be assigned without reservation to Tiliaceae (Pteleaecarpum = Craigia) or Caprifoliaceae (“Ptelea” cassioides [part], “Ptelea” miocenica [part]). Taxonomic affinities of the two remaining fruit types (“Pteleaeocenica, “Pteleacassioides [part]) are undetermined. Genuine fossil Ptelea samaras are restricted to Miocene floras in the western United States, including the Hog Creek (Weiser) and Succor Creek floras near the Oregon–Idaho border and the Stinking Water flora of east-central Oregon. These samaras bear the names P. miocenica Berry and P. enervosa H. V. Smith. The holotype of P. miocenica is a caprifoliaceous infructescence similar to that of Dipelta Maximowicz, so P. enervosa, previously considered a synonym of P. miocenica, is the valid combination for fossil Ptelea samaras. P. enervosa samaras are the oldest reliably determined fossil Ptelea fruits. These samaras indicate that the Toddalieae-Pteleinae lineage of subfamily Toddalioideae has been present in North America since the Miocene, rather than the Eocene as suggested by previously misidentified specimens.  相似文献   

6.
《Plains anthropologist》2013,58(37):300-317
Abstract

The often referred to but little understood “Fox Project” is re-examined through the use of the primary documents contained within the report Documentary History of the Fox Project: A Program of Action Anthropology (Gearing et al.,1960), Many basic questions are raised concerning the role of the “action” anthropologist in a native community. Through the use of the case study method, many of the pitfalls that await the unwary anthropologist in this type of endeavor are vividly illustrated. Finally, the need for independent evaluative studies of “action” projects is pointed out.  相似文献   

7.
《Plains anthropologist》2013,58(14):221-229
Abstract

A criticism is made of the identification of site 39LM57, the “Ft. Lookout II of the French Fur Trading Co.” in a recent publication of the River Basin Surveys Papers, Bureau of American Ethnology Bulletin, No. 176. Events in the history of the upper Missouri fur trade, 1822 to 1852, are examined to show that this site was not the location of a post operated by the “French Fur Trading Co. “between 1831 and 1840, or the “La Barge Post” of 1840-1851. The evidence is presented to substantiate the view that there was no “French Company” trading in the Fort Lookout area during the time indicated. Also it is stated that during the 1840’s, the post referred to as “Fort Lookout” was actually the Yankton trading house located on the east side of the Missouri, across the river from the traditional Fort Lookout area.  相似文献   

8.
《Plains anthropologist》2013,58(50):305-306
Abstract

Recent ethnographic work with Cree informants supports the hypothesis that the original Cree. term for “Blackfoot” Indians referred to animal (perhaps horse’s) hooves rather than to artificially blackened feet or moccasins.  相似文献   

9.
Purpose

The purpose of this study is to provide an integrated method to identify the resource consumption, environmental emission, and economic cost for mechanical product manufacturing from economic and ecological dimensions and ultimately to provide theoretical and data support of energy conservation and emission reduction for mechanical product manufacturing.

Methods

The applied research methods include environmental life cycle assessment (LCA) and life cycle cost (LCC). In life cycle environmental assessment, the inventory data are referred from Chinese Life Cycle Database and midpoint approach and EDIP2003 and CML2001 models of life cycle impact assessment (LCIA) are selected. In life cycle cost assessment, three cost categories are considered. The proposed environment and cost assessment method is based on the theory of social willingness to pay for potential environmental impacts. With the WD615 Steyr engine as a case, life cycle environment and cost are analyzed and evaluated.

Results and discussion

The case study indicates that, in different life cycle phases, the trend of cost result is generally similar to the environmental impacts; the largest proportion of cost and environmental impact happened in the two phases of “material production” and “component manufacturing” and the smallest proportion in “material transport” and “product assembly.” The environmental impact category of Chinese resource depletion potential (CRDP) accounted for the largest proportion, followed by global warming potential (GWP) and photochemical ozone creation potential (POCP), whereas the impacts of eutrophication potential (EP) and acidification potential (AP) are the smallest. The life cycle “conventional cost” accounted for almost all the highest percentage in each phase (except “material transport” phase), which is more than 80% of the total cost. The “environmental cost” and “possible cost” in each phase are relatively close, and the proportion of which is far below the “conventional cost.”

Conclusions

The proposed method enhanced the conventional LCA. The case results indicate that, in a life cycle framework, the environment and cost analysis results could support each other, and focusing on the environment and cost analysis for mechanical product manufacturing will contribute to a more comprehensive eco-efficiency assessment. Further research on the life cycle can be extended to phases of “early design,” “product use,” and “final disposal.” Other LCIA models and endpoint indicators are advocated for this environmental assessment. Environmental cost can also be further investigated, and the relevant social willingness to pay for more environmental emissions is advocated to be increased.

  相似文献   

10.
《Plains anthropologist》2013,58(98):287-305
Abstract

The Highwalker site is a two component prehistoric encampment located in the Pine Parklands region of southeastern Montana. The Late Prehistoric period occupation represents a briefly used, special purpose site occupied by a Native American group primarily engaged in the final butchering of bison and the processing of its by-products. Two radiocarbon samples date the Late Prehistoric period occupation between A.D. 1000 and A.D. 1100. Ceramics recovered from this component shed some light on the debate concerning “Crow Pottery” and Late Prehistoric period cultural systematics. The ceramics represent the earliest known representatives of a localized Powder River Basin pottery tradition which appears to be related to Extended Middle Missouri Tradition ceramics. These nomadic Powder River Basin ceramic-using groups maintained contact with the Middle Missouri village farmers and were influenced by their pottery technology. Later when the ethnographically known Crow moved into the area, the Powder River Basin hunting groups either were amalgamated into Crow society or were driven from the area.  相似文献   

11.
AimsMelatonin is a hormone synthesized principally in the pineal gland that has been classically associated with endocrine actions. However, several lines of evidence suggest that melatonin plays a role in pain modulation. This paper reviews the available evidence on melatonin's analgesic effects in animals and human beings.Main methodsA medline search was performed using the terms “melatonin”, “inflammatory pain”, “neuropathic pain”, “functional pain”, “rats”, “mice”, “human”, “receptors”, “opioid” and “free radicals” in combinations.Key findingsThe antinociceptive effect of melatonin has been evaluated in diverse pain models, and several findings show that melatonin receptors modulate pain mechanisms as activation induces an antinociceptive effect at spinal and supraspinal levels under conditions of acute and inflammatory pain. More recently, melatonin induced-antinociception has been extended to neuropathic pain states. This effect agrees with the localization of melatonin receptors in thalamus, hypothalamus, dorsal horn of the spinal cord, spinal trigeminal tract, and trigeminal nucleus. The effects of melatonin result from activation of MT1 and MT2 melatonin receptors, which leads to reduced cyclic AMP formation and reduced nociception. In addition, melatonin is able to activate opioid receptors indirectly, to open several K+ channels and to inhibit expression of 5-lipoxygenase and cyclooxygenase 2. This hormone also inhibits the production of pro-inflammatory cytokines, modulates GABAA receptor function and acts as a free radical scavenger.SignificanceMelatonin receptors constitute attractive targets for developing analgesic drugs, and their activation may prove to be a useful strategy to generate analgesics with a novel mechanism of action.  相似文献   

12.
ObjectivesThe aim of this study was to determine the association of “ABO” and “Rhesus” blood groups with incidence of breast cancer.MethodsIn this study, we identified 70 research documents from data based search engines including “PubMed”, “ISI-Web of Knowledge”, “Embase” and “Google Scholar”. The research papers were selected by using the primary key-terms including “ABO blood type”, “Rhesus” blood type and “breast cancer”. The research documents in which “ABO” and “Rhesus” blood types and breast cancer was debated were included. After screening, we reviewed 32 papers and finally we selected 25 research papers which met the inclusion criteria and remaining documents were excluded.ResultsBlood group “A” has high incidence of breast cancer (45.88%), blood group “O” has (31.69%); “B” (16.16%) and blood group “AB” has (6.27%) incidence of breast cancer. Blood group “A” has highest and blood group “AB” has least association with breast cancer. Furthermore, “Rhesus +ve” blood group has high incidence of breast cancer (88.31%) and “Rhesus –ve” blood group has least association with breast cancer (11.68%).ConclusionBlood group “A” and “Rhesus +ve” have high risk of breast cancer, while blood type “AB” and “Rhesus –ve” are at low peril of breast cancer. Physicians should carefully monitor the females with blood group “A” and “Rh +ve” as these females are more prone to develop breast cancer. To reduce breast cancer incidence and its burden, preventive and screening programs for breast cancer especially in young women are highly recommended.  相似文献   

13.
BackgroundMost recalcitrant infections are associated to colonization and microbial biofilm development. These biofilms are difficult to eliminate by the immune response mechanisms and the current antimicrobial therapy.AimTo describe the antifungal of micafungin against fungal biofilms based in the scientific and medical literature of recent years.MethodsWe have done a bibliographic retrieval using the scientific terms “micafungin”, “activity”, “biofilm”, “Candida”, “Aspergillus”, “fungi”, “mycos”*, susceptibility, in PubMed/Medline from the National Library of Medicine from 2006 to 2009.ResultsMost current antifungal agents (amphotericin B and fluconazole) and the new azole antifungals have no activity against fungal biofilms. However, micafungin and the rest of echinocandins are very active against Candida albicans, Candida dubliniensis, Candida glabrata, and Candida krusei biofilms but their activities are variable and less strong against Candida tropicalis and Candida parapsilosis biofilms. Moreover, they have not activities against the biofilms of Cryptococcus y Trichosporon.ConclusionsThe activity of micafungin against Candida biofilms gives more strength to its therapeutic indication for candidaemia and invasive candidiasis associated to catheter, prosthesis and other biomedical devices.  相似文献   

14.
《Comptes Rendus Palevol》2018,17(3):201-219
Heavy-duty scrapers are documented as a specific morphotype in ancient African and Eurasian toolkits from the Oldowan into the Acheulian. They are characterized by a flat platform perpendicularly oriented to a carinated edge. The convex surface of that edge displays semi-peripheral, unidirectional removals associated with steep retouch and/or crush marks. This morphotype has been described from numerous sites covering a long temporal scale and are diversely referred to in French as “rostro-carénés” or “nucléus-racloirs” and in English as “massive scrapers”, “core scrapers”, “large scrapers”, or “heavy end-scrapers”. Morpho-technological definitions and interpretations are reviewed to track the origin and evolution of heavy-duty scrapers over time and space. Results show that tools referred to as heavy-duty scrapers were made on thick cobbles during the Oldowan, and later, at the onset of the Acheulian, on Large Flakes, while smaller-sized items in Late Acheulian sites assume end-scraper morphologies. But should all of these tools really be grouped under a single denomination? Experimental work explores whether heavy-duty scrapers are the result of knapping processes, or if their morphology could be derived from other kinds of activities. Chronological continuity of the attributes specific to heavy-duty scrapers points to their role in ancient toolkits, suggesting that these scarce but ubiquitous primitive implements are, on equal footing with chopper-cores, one of the oldest morphotypes in the world.  相似文献   

15.
PurposeThough the number of women scientists is increasing over the years, studies show that they are still under-represented in leadership roles. The purpose of this work is to establish the percentage of women Medical Physicists (wMPs) that have participated in European scientific events and evaluate it as an indication of the current position of women in the field of Medical Physics in Europe and to propose possible ways to encourage their participation.Materials and MethodsData regarding the participants in European scientific events of Medical Physics were collected. The participants were divided into categories according to the program of the events and their gender was identified. The percentage of wMPs in each category was evaluated.ResultsThe participation of wMPs attending courses is greater than 50%. The categories with the greatest participation are “Organizing Committees”, “Chairpersons-Moderators” and “Oral Presentations”. The categories with the lower participation of wMPs are “Scientific Committee”, “Symposiums” and “Invited Speakers”. None of wMPs were represented as “Course Directors”.ConclusionsThe attendance of wMPs in courses is slightly greater than average. However, wMPs do not have an equally important recognition in special invited roles in conferences. They are still under-represented in “Scientific Committees”, “Invited Speakers”, “Symposiums” and “Course directors”. wMPs should be encouraged to participate even more actively in European conferences and the organizing committees should invite more wMPs in special roles. More studies concerning the status of female MPs in each country separately should be encouraged as they will help in understanding the position of wMPS in Europe.  相似文献   

16.
《IRBM》2020,41(6):354-363
ObjectivesAfter a century of spectacular advances, healthcare systems are facing unprecedented crisis, linked to shortage of health human resources and health technologies. In fact, availability of care depends on both technological and human resources of health. The objective of this study is to develop indicators that can measure qualitatively human resources and technologies of health in healthcare facilities, in order to assess availability of care in sub-Saharan African countries.Materials and MethodsRegarding “health technology” related to “medical devices”, an indicator called “TechSan” for “Technologies de Santé” was previously developed and published (Ndione FB et al. (2019) [6]). To address the deficiencies in usual indicators related to health human resources, a second indicator called “RhSan” for “Ressources humaines de santé” in French is proposed. This indicator assigns a weight to each health worker taking into account his specific “level of medical knowledge” and “experience”. In order to correlate “RhSan” with “TechSan”, a third indicator called “RhTech” is also developed to assess matches between “health technologies” and “health human resources” and establish realistic availability of care. These indicators have the advantage to be consolidated by specialty such as laboratory, imaging, surgery, and “mother and child care”.ResultsThe application of TechSan, RhSan and RhTech to data collected in Senegal in 2016, enabled to assess the distribution of “health technology” and “health human resources” in this country. They also permit the mapping of care availability per specialty in Senegal. The results show a strong oversupply of Dakar in terms of both human resources and technologies of health compared to other Senegalese regions. Oppositely, Sedhiou, Kaffrine, Matam and Kédougou are poorly endowed showing limits of the Senegalese health pyramid system.ConclusionTechSan, RhSan and RhTech can provide reliable decision-making tools in order to elaborate health policies in sub-Saharan African countries on more rigorous basis.  相似文献   

17.
The ice formation in a water body is examined for the computation of temperature field, phase change and a moving ice–water interface whose location is not known à priori. This is classically referred to as the Stefan problem [Rubinstein, L.I. (1971) The Stefan Problem (American Mathematical Society, Providence, Rhode Island 02904]. Based on the Duvaut [Duvaut, G. (1973) “Résolution d'un problème de Stefan” C.R. Acad. Sci. Paris 276, 1461–1463] transformation, the governing equations for heat conduction are formulated within a variational principle that is readily amenable to a standard finite element solution without remeshing. Numerical simulation results pertaining to the freezing of tumour tissue in a multi-cryoprobe cryosurgery are presented. These results lend both quantitative and graphical support to the current empirical standards of “effective therapy” in view of refining clinical applications.  相似文献   

18.
PurposeTo propose a “staggered overlap” technique in volumetric modulated arc therapy (VMAT) for craniospinal irradiation (CSI) and compare the dose distribution and plan robustness with “overlap” technique and “gradient optimization” approach.Methods and Materials6 patients previously treated in our clinic were retrospectively selected. 9 VMAT plans of each patient were optimized with “staggered overlap”, “overlap” and “gradient optimization” in overlapping region of 3 cm, 6 cm, and 9 cm separately. For the “staggered overlap” plan, adjacent field sets were intentionally overlapped by staggering field edges in an appropriate step size to avoid sharp dose gradient. Evaluation metrics including V95%, D2%, D98%, conformity number (CN) and homogeneity index (HI) were employed to evaluate the dose distribution. Moreover, shifts of the upper spinal field isocenter in each direction were performed to simulate junction errors for robustness analysis.ResultsThe CN and HI of VMAT plans with “staggered overlap” were 0.82 (0.811–0.822) and 0.113 (0.112–0.114), while they were 0.778 (0.776–0.782) and 0.131 (0.130–0.131) for plans with “gradient optimization”. In the robustness study, <3% dose deviations were found for 5 mm shifts in lateral and vertical directions with all techniques. In cranial-caudal direction, “overlap” technique created hot spots (D2% > 170%) and cold spots (D98% < 44%) in the junction region with 10 mm shifts. The dose deviations were decreased to 22% for plans with “staggered overlap” and 9 cm overlapping region.Conclusion“Staggered overlap” technique provides better plan quality as compared to “gradient optimization” approach and makes the plan more robust against junction errors as compared to “overlap” technique.  相似文献   

19.
BackgroundHowever, broad adoption of herbal remedies for giardiasis is at present hampered by uncertain findings of investigation not always sufficiently powered. This study was aimed at systematically reviewing the existing literature in herbal medicines to treat giardiasis.MethodsThis review was carried out 06- PRISMA guideline and registered in the CAMARADES-NC3Rs Preclinical Systematic Review and Meta-Analysis Facility (SyRF) database. The search was performed in five databases which are Scopus, PubMed, Web of Science, EMBASE, and Google Scholar without time limitation for all published articles (in vitro, in vivo, and clinical studies). The searched words and terms were: “Giardia”, “giardiasis”, “extract”, “essential oil”, “herbal medicines”, “anti-Giardia”, “In vitro”, “In vivo”, “clinical trial” etc.ResultsOut of 1585 papers, 40 papers including 28 in vitro (70.0%), 7 in vivo (17.5%), 2 in vitro/ in vivo (5.0%), and 3 clinical trials (7.5%) up to 2020, met the inclusion criteria for discussion in this systematic review. The most widely used medicinal plants against Giardia infection belong to the family Lamiaceae (30.0%) followed by Asteraceae (13.5%), Apiaceae (10.5%). The most common parts used in the studies were aerial parts (45.0%) followed by leaves (27.4%) and seeds (7.5%). The aqueous extract (30.0%), essential oil (25.4%) and hydroalcholic and methanolic (10.5%) were considered as the desired approaches of herbal extraction, respectively.ConclusionThe current review showed that the plant-based anti-Giardia agents are very promising as an alternative and complementary resource for treating giardiasis since had low significant toxicity. However, more studies are required to elucidate this conclusion, especially in clinical systems.  相似文献   

20.
AimA systemic review and analysis of evolution journey of indices, such as conformity index (CI), homogeneity index (HI) and gradient index (GI), described in the literature.BackgroundModern radiotherapy techniques like VMAT, SRS and SBRT produce highly conformal plans and provide better critical structure and normal tissue sparing. These treatment techniques can generate a number of competitive plans for the same patients with different dose distributions. Therefore, indices like CI, HI and GI serve as complementary tools in addition to visual slice by slice isodose verification while plan evaluation. Reliability and accuracy of these indices have been tested in the past and found shortcomings and benefits when compared to one another.Material and methodsPotentially relevant studies published after 1993 were identified through a pubmed and web of science search using words “conformity index”, “Homogeneity index”, “Gradient index”,” Stereotactic radiosurgery”,” stereotactic Body radiotherapy” “complexity metrics” and “plan evaluation index”. Combinations of words “plan evaluation index conformity index” were also searched as were bibliographies of downloaded papers.Results and conclusionsMathematical definitions of plan evaluation indices modified with time. CI definitions presented by various authors tested at their own and could not be generalized. Those mathematical definitions of CI which take into account OAR sparing grant more confidence in plan evaluation. Gradient index emerged as a significant plan evaluation index in addition to CI whereas homogeneity index losing its credibility. Biological index base plan evaluation is becoming popular and may replace or alter the role of dosimetrical indices.  相似文献   

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