首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Morphological variations of the deciduous dentition are as useful as those of the permanent dentition for determining the biological affinities of human populations. This paper provides material on morphological variations of deciduous teeth of the prehistoric Japanese population from the Late and the Latest Jomon Period (ca. 2000–ca. 300 B.C.). The expression of nonmetric traits of the deciduous teeth in the Jomon sample shows a closer affinity with modern Japanese and Native American samples than with American White, Asiatic Indian, and African samples. However, the frequency of shoveling in deciduous upper incisors in the Jomon sample is lower than those in modern Japanese and Native American samples. The Jomon sample also expresses a much higher frequency of cusp 6 in deciduous lower second molars than seen in modern Japanese, Ainu, and Native American samples. The frequency in the Jomon sample is equal to that in the Australian Aboriginal sample, which shows cusp 6 most frequently among the samples compared. A somewhat low incidence of incisor shoveling in the Jomon sample was also reported in the permanent dentition (Turner [1976] Science 193:911–913, [1979] Am. J. Phys. Anthropol. 51:619–635, [1987] Am. J. Phys. Anthropol. 73:305–321, [1990] Am. J. Phys. Anthropol. 82:295–317; T. Hanihara [1992] Am. J. Phys. Anthropol. 88:163–182, 88:183–196). However, the frequency of cusp 6 in the Jomon sample shows no significant difference from those of Northeast Asian or Native American samples in the permanent dentition (Turner [1987] Am. J. Phys. Anthropol. 73:305–321; T. Hanihara [1992] Am. J. Phys. Anthropol. 88:1–182, 88:183–196). Evidently, some nonmetric traits express an inter-group difference only in the deciduous dentition. © 1995 Wiley-Liss, Inc.  相似文献   

2.
Kelly Bulkeley 《Dreaming》1999,9(1):101-109
This essay explores the complex interplay of dreams and film, using an analysis of The Wizard of Oz (1939) and A Nightmare on Elm Street (1984) to illustrate how an interdisciplinary approach can provide fruitful insights into how dreams influence films, and films influence dreams. The essay suggests that reflecting on the dreams-film connection can deepen our understanding of the cultural dimensions of human development, particularly in the context of modern American culture. By using the methodological resources of psychology, sociology, history, film criticism, and theology, the essay argues more generally that the interdisciplinary analysis of films offers significant new possibilities for the development of dream studies. Kelly Bulkeley, Ph.D.  相似文献   

3.
Previous research (Tague [1994] Am. J. Phys. Anthropol. 95:27–40) has shown an age effect in pubic bone length among adult women. Tague found that in three prehistoric Native American skeletal samples, women aged 18–24 had a significantly shorter linea terminalis than did women aged 25 and older. The purpose of this research is to determine whether such a difference can be discerned in other female skeletal samples. Three female skeletal samples were used in this analysis: 75 African-American and 42 European-American females aged 18–39 from the Hamann-Todd Collection (collected between 1893 and 1938; Iscan, 1990) and 99 African-American females aged 18–39 from the Terry Collection (collected between 1914 and 1965; Cobb, 1933; Iscan, 1990). Several chord measurements of pubic bone length along the linea terminalis were analyzed by one-tailed t-tests of the separate samples subdivided into two age groups: 18–24 and 25–39 years. Of 15 comparisons between age groups, none differed significantly by age group within each sample. It is concluded that the observed significant difference in pubic bone length in the Native American female skeletal samples cannot be replicated in other samples and that there is no age effect on pubic bone length in the samples tested in this analysis. Tague's findings reflect either the occurrence of late menarche in prehistoric populations or differential survivorship. Am J Phys Anthropol 106:323–328, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

4.
5.
The adhesion of primary chondrocytes to polyelectrolyte multilayer films, made of poly(l-lysine) (PLL) and hyaluronan (HA), was investigated for native and crosslinked films, either ending by PLL or HA. Crosslinking the film was achieved by means of a water-soluble carbodiimide in combination with N-hydroxysulfosuccinimide. The adhesion of macrophages and primary chondrocytes was investigated by microscopical techniques (optical, confocal, and atomic), providing useful information on the cell/film interface. Native films were found to be nonadhesive for the, primary chondrocytes, but could be degraded by macrophages, as could be visualized by confocal laser scanning microscopy after film labeling. Confocal microscopy images show that these films can be deformed by the condrocytes and that PLL diffuses at the chondrocyte membrane. In contrast, the cells adhered and proliferated well on the crosslinked films, which were not degraded by the macrophages. These results were confirmed by a MTT test over a 6-d period and by atomic force microscopy observations. We thus prove that chemical crosslinking can dramatically change cell adhesion properties, the cells being more stably anchored on the crosslinked films. Both authors kcontributed equally.  相似文献   

6.
The 13C off-resonance rotating frame spin–lattice relaxation technique is applicable to the study of protein rotational diffusion behavior in a variety of experimental situations. The original formalism of James and co-workers (1978) (J. Am. Chem. Soc. Vol. 100, pp. 3590–3594) incorporated random isotropic reorientational motion of a rigid spherical rotor with no provision for backbone or side-chain carbonyl group internal motion. Here we demonstrate that the failure to include such internal motion may lead to erroneous rotational correlation time determinations for overall reorientational motion. The effect becomes severe for protein molecular masses in excess of 100 kD. Inclusion of both backbone and side-chain carbonyl carbon internal motion, using reasonable parameters derived from the literature [R. Levy and M. Karplus (1979), Chemical Physics Letters, Vol. 65, pp. 4–11; G. Careri, P. Fasella, and E. Gratton (1975), Critical Reviews in Biochemistry, Vol. 3, pp. 141–164; G. Lipari, A. Szabo, and R. Levy (1982), Nature, Vol. 300, pp. 197–198], plus corrections for anisotropic tumbling [C. F. Morgan, T. Schleich, G. H. Caines, and D. Michael (1990), Biopolymers, Vol. 29, pp. 469–480] and microscopic viscosity [S. H. Koenig (1980), ACS Symposium. Series, Vol. 127, pp. 157–176], leads to reliable values for the correlation time describing overall protein reorientation up to molecular masses of approximately 1000 kD. © 1993 John Wiley & Sons, Inc.  相似文献   

7.
Kenneth Lunn (ed.), Hosts, Immigrants, and Minorities: Historical Responses to Newcomers in British Society, 1870–1914; Folkestone: Dawson, 1980, 377 pp., £15.00.

Colin Holmes, Antisemitism in British Society, 1876–1939; London: Arnold, 1979, 328 pp., £13.50.

Gisela C. Lebzelter, Political Antisemitism in England, 1918–39; London: Macmillan, in association with St Antony's College, Oxford, 1978, 222 pp., £10.00.

Kenneth Lunn & Richard C. Thurlow (eds), British Fascism: Essays on the Radical Right in Inter‐War Britain; London: Croom Helm, 1980, 234 pp., £12.95.  相似文献   

8.

Objectives

Limited studies have focused on how European contact and colonialism impacted Native American oral microbiomes, specifically, the diversity of commensal or opportunistically pathogenic oral microbes, which may be associated with oral diseases. Here, we studied the oral microbiomes of pre-contact Wichita Ancestors, in partnership with the Descendant community, The Wichita and Affiliated Tribes, Oklahoma, USA.

Materials and Methods

Skeletal remains of 28 Wichita Ancestors from 20 archeological sites (dating approximately to 1250–1450 CE) were paleopathologically assessed for presence of dental calculus and oral disease. DNA was extracted from calculus, and partial uracil deglycosylase-treated double-stranded DNA libraries were shotgun-sequenced using Illumina technology. DNA preservation was assessed, the microbial community was taxonomically profiled, and phylogenomic analyzes were conducted.

Results

Paleopathological analysis revealed signs of oral diseases such as caries and periodontitis. Calculus samples from 26 Ancestors yielded oral microbiomes with minimal extraneous contamination. Anaerolineaceae bacterium oral taxon 439 was found to be the most abundant bacterial species. Several Ancestors showed high abundance of bacteria typically associated with periodontitis such as Tannerella forsythia and Treponema denticola. Phylogenomic analyzes of Anaerolineaceae bacterium oral taxon 439 and T. forsythia revealed biogeographic structuring; strains present in the Wichita Ancestors clustered with strains from other pre-contact Native Americans and were distinct from European and/or post-contact American strains.

Discussion

We present the largest oral metagenome dataset from a pre-contact Native American population and demonstrate the presence of distinct lineages of oral microbes specific to the pre-contact Americas.  相似文献   

9.
Objective: Data on Native American children and adolescents are rarely reported along with other racial and ethnic groups. The Healthy Kids Project is part of an effort to describe the prevalence of overweight and obesity in a racially mixed rural area where Native American, Hispanic, African American, and white children reside. Methods and Procedures: We measured height and weight of students in Anadarko, Oklahoma public schools (n = 1,980) in 2002–2003. All available students (95.7%) whose parents had not opted out of school health assessments were included. From these data, we calculated BMI (weight (kg) / height (m2)) and used the International Obesity Task Force reference to classify children into BMI categories. Results: Native American, Hispanic, African American, and white children who live and attend school in the same surroundings are at risk of overweight and obesity. White children had the lowest combined prevalence of overweight and obesity (37.6%), and Native American children had the highest (53.8%) followed closely by African American (51.7%) and Hispanic children (50.5%). Discussion: The childhood obesity epidemic includes all racial and ethnic groups to different degrees. In a rural public school, Native American, Hispanic, and African children had higher rates of overweight/obesity than white children.  相似文献   

10.
The Emma field cricket, Teleogryllus emma (Ohmachi & Matsuura), distributed between 43°N and 30°N in the Japanese archipelago, is univoltine and overwinters in the egg stage. Its eggs hatch on the slope of the Oishi Dam (38.03°N, 139.57°E, 160–170 m a.s.l.) in late June, adults begin emerging from late August, and oviposition lasts until early October. Oviposition is limited to the period when the water level of the Oishi Dam is low. The period from egg hatching to adult emergence is approximately 1 month shorter than that of the T. emma population on the Arakawa riverside (38.09°N, 139.57°E, 29 m a.s.l.), which is approximately only 7 km from the Oishi Dam. The egg and body sizes of T. emma on the slope of the Oishi Dam were smaller than those of T. emma on the Arakawa riverside, and the egg and nymphal periods were shorter; these variations were inherited by the next generation of T. emma. The egg period, nymphal period and head width of T. emma on the dam slope correspond to those of the populations near 40°N. Several traits of the T. emma population on the dam slope were naturally selected by adapting to the isolated environment, resulting in the genetic variations. However, their variations were small and the period after isolation is short, suggesting that it is in the early stages of speciation.  相似文献   

11.
Thermodynamics of contact angle phenomena is strongly affected by the presence of thin liquid films. However, at present, studies for CO2/brine/mineral systems only consider the films apart from contact angles. In this paper, molecular dynamics (MD) simulations have been performed to simultaneously investigate the interrelationship between water film thicknesses and water contact angles. Two types of contact angles were considered namely Young’s contact angle (no water film is present) and contact angle with film (a stable film is present). The results showed that as Young’s contact angle increased, film thickness decreased which leading to increasing of contact angle with film. The effects of CO2-mineral pre-contact have also been investigated and it has been found that on mediate hydrophilic surfaces (Q3), water films were present when CO2 droplets were placed above the surfaces, however, water films were absent when CO2 droplets directly contact with the surfaces. This phenomenon implies that water films on mineral surfaces have a possibility to rupture and a film rupture mechanism for CO2 adhesion on hydrated mineral surfaces was proposed. These results may provide new information on interactions among CO2, water/brine and mineral to better understand the behaviour of CO2 during geologic sequestration.  相似文献   

12.
EDITORIAL     
C. D. PRIEST 《Ostrich》2013,84(1):25-34
Olver, M. D. &; Kuyper, M. A. 1978. Breeding biology of the Whitebreasted Cormorant in Natal. Ostrich 49:25-30.

From 1972–1975 Whitebreasted Cormorants Phalacrocorax carbo bred at the Cedara Dam, Natal, South Africa (29 32S, 30 17E), and from 1973 they fished for food at Midmar Dam, 5 km away and carried the food back to the nestlings. Breeding occurred from April to October and was preceded by a period of courtship. Nesting material was collected by the males and the nests built by the females. The mean clutch size for 1972–1973 was 3,1. Both parents incubated the eggs and guarded the nest and chicks. Growth of the chicks was studied in 1972–1973. The mean number of chicks reared was 1,6 per nest although seven nests contained three nestlings. At 28 days they left the nest when alarmed, but could not fly until 49 days old. The average flying age appeared to be about 53 days. The height of the nests above the ground seemed to determine the nest leaving age. Of the 186 eggs laid in the 60 nests observed over two years, 74% hatched. Fledging success was 52% of eggs laid and 69% of eggs hatched. Chick mortality seemed to be caused mainly by falling from the nests and dying of starvation.  相似文献   

13.
To study the effect of brain signals on the biosynthesis of juvenile hormone by the corpora allata of the grey fleshfly Neobellieria bullata, exposed corpora allata connected to the brain were surgically removed from sugar-fed flies and incubated in vitro with L -[3H-methyl]methionine. After incubation, the media together with the tissues were analyzed by HPLC. [3H]Juvenile hormone III (JH III), [3H]JH III bisepoxide (BE), [3H]methyl farnesoate (MF) and an unknown [3H]labeled metabolite (Un) were identified as the primary products. The rate of synthesis of [3H]JH III bisepoxide was higher than that of [3H]JH III, [3H]MF and [3H]Un. Two days after a liver meal, female flies synthesized more JH III, MF, BE, and the Un than did males. Synthesis of JH III, BE, and MF in females was lower during the previtellogenic, sugar-feeding period than during the vitellogenic liver-feeding period. Isolated corpus cardiacum–corpus allatum (CC-CA) complexes that were incubated in vitro synthesized less JH III, MF, and BE, as compared to complexes that were attached to the brain, indicating that the brain probably modulates the biosynthesis of JH III, MF, and BE in the corpora allata. Upon incubation of brain–CC–CA complexes with Neb-TMOF (10–8 M), Neb-colloostatin (10–8 M), ovarian, or brain extracts resulted in significant inhibition of JH III and BE biosynthesis in the presence of ovarian extracts. These results indicate that allatostatin-like factors are present in the ovary of the flesh fly. Arch. Insect Biochem. Physiol. 37:248–256, 1998. © 1998 Wiley–Liss, Inc.  相似文献   

14.

“Women's film” in Hollywood is associated both with the genre of melodrama, the “weepie”, and with female spectatorship. In the Indian context of popular Hindi cinema, first, genre analysis itself is a questionable line of inquiry since several genres, the melodrama, musical, gangster, or mystery, combine in a single film, known locally as the masala (spicy) film; and second, films are scarcely divided by a gendered viewership. Yet I identify “women's films” as a distinct category in Hindi cinema, emerging around the ‘70s. These women's films typically center on female protagonists, dramatize their victimization and vindication; by the ‘80s under a range of influences these films mutated into rape‐revenge narratives.

However, another strain emerged within the ‘70s’ “women's film,” which drew on cinema's rich visual iconographic tradition of the sight gag, promulgating the comedic/tomboy heroine figure. It favored laughing and mocking patriarchal structures rather than surrendering to them in tears. Focusing on Ramesh Sippy's Sita aur Gita [1972] emblematic of this trend I explore theoretical concerns about associating genres with gender. In keeping with recent poststructuralist theories about gender and media ‘consumption I show how the film destabilized clear‐cut gender identification and stood for a promising trend that was sadly undercut. Thus, while genre might still be a useful analytical tool for Hindi cinema, defining women's film as female‐centered narratives is a viable category as long as we appreciate the instability in gendered viewer identification.  相似文献   

15.
D. C. H. Plowes 《Ostrich》2013,84(3):133-144
Olver, M.D. 1984. Breeding biology of the Reed Cormorant. Ostrich 55:133-140.

The breeding biology of the Reed Cormorant Phalacrocorax africanus was studied at Cedara Dam, Natal, South Africa, from 1973 to 1975. Breeding occurred from November to February and was preceded by a period of courtship. Mean clutch size was 3,6 eggs and mean egg measurements were 44,2 x 29,5 mm. The average incubation period was 23,3 days. Young leave the nest at 28 days when alarmed but cannot fly until 35 days old. Hatching success was 84,1%, and fledging success 60,6%.  相似文献   

16.
Buccal bioadhesive films, releasing topical drugs in the oral cavity at a slow and predetermined rate, provide distinct advantages over traditional dosage forms. The aim of present study was to prepare and evaluate buccal bioadhesive films of clotrimazole for oral candidiasis. The film was designed to release the drug at a concentration above the minimum inhibitory concentration for a prolonged period of time so as to reduce the frequency of administration of the available conventional dosage forms. The different proportions of sodium carboxymethylcellulose and carbopol 974P (CP 974P) were used for the preparation of films. Carbopol was used to incorporate the desired bioadhesiveness in the films. The films were prepared by solvent casting method and evaluated for bioadhesion, in vitro drug release and effectiveness against Candida albicans. In vitro drug release from the film was determined using a modified Franz diffusion cell while bioadhesiveness was evaluated with a modified two-arm balance using rabbit intestinal mucosa as a model tissue. Films containing 5% CP 974P of the total polymer were found to be the best with moderate swelling along with favorable bioadhesion force, residence time and in vitro drug release. The microbiological studies revealed that drug released from the film could inhibit the growth of C. albicans for 6 h. The drug release mechanism was found to follow non-Fickian diffusion.  相似文献   

17.
We describe a modification and post‐functionalization technique for a donor–acceptor–donor type monomer; 6‐(4,7‐bis(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐5‐yl)‐2H‐benzo[d][1,2, 3]triazol‐2‐yl)hexan‐1‐amine. Folic acid was attached to the fluorescent structure. The conjugation was confirmed via NMR and Fourier transform infrared analyses. Cytotoxicity was investigated and the comparison of association of targeted monomeric structures in tumor cells was monitored via fluorescence microscopy. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:952–959, 2014  相似文献   

18.
Summary Key factor analysis techniques were used to examine factors determining the abundance of a population of non-pest Colias. The number of individuals entering each successive life stage in the sample population are summarized in life tables for 1975 to 1979. Survivorship to the adult is a relatively consistent proportionality (-x=1.2%, S.D.=1.14; 1975–1979). Factors resulting in reduced natality and, less importantly, mortality during larval diapause determine the population trends for C. alexandra. Egg mortality, pre-diapause larval mortality and postdiapause mortality contribute little to these trends. Possible key sources contributing to reduced natality are examined. Mortality of adults (including removal by collectors), poor weather conditions during the oviposition period, unseasonal snow or drought which affect nectar sources or oviposition sites are among the factors which cause reduced natality and result in population depression.  相似文献   

19.
A protocol is presented for an efficient and practical approach to the synthesis of enantiomerically pure bicyclo[3.3.0]octane derivatives from achiral Cs‐symmetric bicyclo[3.3.0]octane‐2,8‐dione using a diastereomeric resolution‐selective deprotection method. This method affords chiral building blocks having bicyclo[3.3.0]octane framework with the same site of diastereotopic carbonyl functional group. Chirality 27:364–369, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

20.
Recent work (Hizi and Yagil [1974] Eur. J. Biochem. 45: 211–221, and Kelly et. al. [1975] Fed. Proc. 34: 881) suggests that the marked increase in rat liver glucose-6-phosphate dehydrogenase activity which is observed upon feeding an animal a high carbohydrate diet does not involve an increase in the total amount of enzyme present. In contrast, the data presented herein involving immunological titrations of rat liver glucose-6-phosphate dehydrogenase indicates that the increase in enzyme activity resulting from feeding a high carbohydrate diet does involve an increase in the total amount of enzyme present.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号