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1.
The late Neandertal sample from Vindija (Croatia) has been described as transitional between the earlier Central European Neandertals from Krapina (Croatia) and modern humans. However, the morphological differences indicating this transition may rather be the result of different sex and/or age compositions between the samples. This study tests the hypothesis that the metric differences between the Krapina and Vindija supraorbital samples are due to sampling bias. We focus upon the supraorbital region because past studies have posited this region as particularly indicative of the Vindija sample's transitional nature. Furthermore, the supraorbital region varies significantly with both age and sex.We analyzed four chords and two derived indices of supraorbital torus form as defined by Smith & Ranyard (1980, Am. J. phys. Anthrop.93, pp. 589-610). For each variable, we analyzed relative sample bias of the Krapina and Vindija samples using three sampling methods. In order to test the hypothesis that the Vindija sample contains an over-representation of females and/or young while the Krapina sample is normal or also female/young biased, we determined the probability of drawing a sample of the same size as and with a mean equal to or less than Vindija's from a Krapina-based population. In order to test the hypothesis that the Vindija sample is female/young biased while the Krapina sample is male/old biased, we determined the probability of drawing a sample of the same size as and with a mean equal or less than Vindija's from a generated population whose mean is halfway between Krapina's and Vindija's. Finally, in order to test the hypothesis that the Vindija sample is normal while the Krapina sample contains an over-representation of males and/or old, we determined the probability of drawing a sample of the same size as and with a mean equal to or greater than Krapina's from a Vindija-based population. Unless we assume that the Vindija sample is female/young and the Krapina sample is male/old biased, our results falsify the hypothesis that the metric differences between the Krapina and Vindija samples are due to sample bias.  相似文献   

2.
ABSTRACT

This article looks at the communal violence in Ambon, Poso, and Sambas in post-Suharto Indonesia from a comparative perspective. It explores why Ambon and Poso were seen as religious while Sambas was seen as ethnic despite the fact that in all three conflicts different religions and ethnicities fought each other. Examining the “ethnic” elements, this article advances three arguments: First, that the Poso and Ambon conflicts were no less ethnic than the Sambas conflict as they had similar “ethnic causes”. Second, that the religious narrative dominated in Ambon and Poso because it reflected the Islamic resurgence in Indonesia since the 1990s while the narrative in Sambas reflected that it was the latest round of a pre-existing anti-Madurese conflict which had already been “defined” as “ethnic”. Third, that the narratives were framed strategically, thus influencing the trajectory of the conflict but also responding to it.  相似文献   

3.
On the prehistoric site of Ploča Mičov Grad (Ohrid, North Macedonia) on the eastern shore of Lake Ohrid a total of 799 wooden elements were recorded from a systematically excavated area of nearly 100 square metres. Most of them are pile remains made of round wood with diameters up to almost 40 cm. A comprehensive dendrochronological analysis allows the construction of numerous well-replicated tree-ring chronologies for different species. High agreements between the chronologies prove that oak, pine, juniper, ash and hop-hornbeam can be crossdated. The chronologies are dated by means of radiocarbon dates and modelling using wiggle matching. An intensive settlement phase is attested for the middle of the 5th millennium BCE. Further phases follow towards the end of the 5th millennium BCE and in the 2nd millennium around 1800, 1400 and 1300 BCE. Furthermore, the exact, relative felling dates allow first insights into the minimum duration of the settlement phases, which lie between 17 and 87 years. The multi-centennial chronologies presented in this study can be used as a first robust dating basis for future research in the numerous not yet dated prehistoric lake shore settlements of the region with excellently preserved wooden remains.  相似文献   

4.
This study determined the potential for periphyton growth on artificial surfaces using plexiglas slides exposed for different lengths of time, orientations and depths in the lower, lentic area of River Krka during the summer of 1995. During the research period, 88 taxa were identified. The most abundant group was Bacillariophyceae with 57 taxa. Species Cyclotella comta (Ehr.) Kutz., Achnanthidium affine (Grunow) Czarn., Cocconeis placentula Ehr. and Eolimna minima (Grunow) Lange-Bertalot were present in all samples. The results show significant differences in abundance, number and composition of algae between growth surfaces and depths. The number of species present shows statistically significant differences with respect to all three variables (days of colonization, depth and orientation), while the total number of cells per square centimeter varies with respect to the days of colonization and the depth only. The highest growth potential was observed after 60 days of exposition on the upper side of the horizontally placed surface at a depth of 1 m. During the same exposition time, the lowest growth potential was noted on the vertical slide at a depth of 18 m. Physical and chemical parameters and their relations to algal periphyton assemblages were also monitored.  相似文献   

5.

Objective

Age at adiposity rebound (AR) is associated with obesity and Type 2 Diabetes in adults. The aim of the present study was to investigate the role of age at AR in adult fat mass, fat distribution and pubertal timing for a Swedish cohort.

Patients and Methods

This is a retrospective cohort study. Detailed growth charts were retrieved for the men participating in the population-based GOOD (Gothenburg Osteoporosis and Obesity Determinants) study (n = 573). Body composition was analysed using dual X-ray absorptiometry and computed tomography at 18–20 years of age. Age and BMI at AR were calculated using pediatric growth charts and AR was defined as the lowest BMI between 3 and 9 years of age.

Results

Subjects were divided into early (age at AR below 5.4 years of age), middle (age at AR 5.4 to 6.8 years of age) and late (age at AR after 6.8 years of age) age at AR tertiles. Subjects in the early age at AR tertile had higher young adult BMI (+8%), whole body fat mass (+34%) and amount of subcutaneous adipose tissue (+61%) than the subjects in the middle and late tertiles (p<0.01). The early age at AR tertile had an increased risk of obesity (Odds Ratio 4.1 [95% CI 1.2–13.9]) compared with the middle and late tertiles. In addition, the early age at AR tertile had Peak Height Velocity (PHV) 7 months earlier than the late tertile.

Conclusions

Early age at AR was associated with young adult obesity as a consequence of a high amount of subcutaneous adipose tissue in men. In addition we made the novel observation that early age at AR was associated with an early puberty in men.  相似文献   

6.

Background

The World Health Organization has recommended three rounds of mass drug administration (MDA) with antibiotics in districts where the prevalence of follicular trachoma (TF) is ≥10% in children aged 1–9 years, with treatment coverage of at least 80%. For districts at 5–10% TF prevalence it was recommended that TF be assessed in 1–9 year olds in each community within the district, with three rounds of MDA provided to any community where TF≥10%. Worldwide, over 40 million people live in districts whose TF prevalence is estimated to be between 5 and 10%. The best way to treat these districts, and the optimum role of testing for infection in deciding whether to initiate or discontinue MDA, are unknown.

Methods

In a community randomized trial with a factorial design, we randomly assigned 48 communities in four Gambian districts, in which the prevalence of trachoma was known or suspected to be above 10%, to receive annual mass treatment with expected coverage of 80–89% (“Standard”), or to receive an additional visit in an attempt to achieve coverage of 90% or more (“Enhanced”). The same 48 communities were randomised to receive mass treatment annually for three years (“3×”), or to have treatment discontinued if Chlamydia trachomatis (Ct) infection was not detected in a sample of children in the community after mass treatment (stopping rule(“SR”)). Primary outcomes were the prevalence of TF and of Ct infection in 0–5 year olds at 36 months.

Results

The baseline prevalence of TF and of Ct infection in the target communities was 6.5% and 0.8% respectively. At 36 months the prevalence of TF was 2.8%, and that of Ct infection was 0.5%. No differences were found between the arms in TF or Ct infection prevalence either at baseline (Standard-3×: TF 5.6%, Ct 0.7%; Standard-SR: TF 6.1%, Ct 0.2%; Enhanced-3×: TF 7.4%, Ct 0.9%; and Enhanced-SR: TF 6.2%, Ct 1.2%); or at 36 months (Standard-3×: TF 2.3%, Ct 1.0%; Standard-SR TF 2.5%, Ct 0.2%; Enhanced-3× TF 3.0%, Ct 0.2%; and Enhanced-SR TF 3.2%, Ct 0.7% ). The implementation of the stopping rule led to treatment stopping after one round of MDA in all communities in both SR arms. Mean treatment coverage of children aged 0–9 in communities randomised to standard treatment was 87.7% at baseline and 84.8% and 88.8% at one and two years, respectively. Mean coverage of children in communities randomized to enhanced treatment was 90.0% at baseline and 94.2% and 93.8% at one and two years, respectively. There was no evidence of any difference in TF or Ct prevalence at 36 months resulting from enhanced coverage or from one round of MDA compared to three.

Conclusions

The Gambia is close to the elimination target for active trachoma. In districts prioritised for three MDA rounds, one round of MDA reduced active trachoma to low levels and Ct infection was not detectable in any community. There was no additional benefit to giving two further rounds of MDA. Programmes could save scarce resources by determining when to initiate or to discontinue MDA based on testing for Ct infection, and one round of MDA may be all that is necessary in some settings to reduce TF below the elimination threshold.  相似文献   

7.
Ale? Hrdli?ka produced a tremendous amount of data in his career, much of which was published in a series of catalogs by the US National Museum. The Gulf States catalog, for example, contains raw craniometric data for over 700 individuals from the state of Florida alone. However, many of these skeletons are poorly sourced by Hrdli?ka, thus limiting their utility in modern bioarchaeological analyses where context is critical. In particular, the age of the skeletal material is often based solely on associated material culture and information on the sites themselves is not presented by Hrdli?ka. To address this impasse we attempted radiocarbon dates for 10 of the largest Florida sites published in the Gulf States catalog. In addition, archival data in the form of unpublished field notes and personal correspondence were accessed to better contextualize the radiocarbon dates and to provide some guidance on the degree of temporal variability at the sites. Eight AMS radiocarbon dates were successful. Archival data was of variable quality per site. In some cases very little is known about the provenience of the specimens. In other cases, however, individual burials could be allocated to specific strata within specific mounds. The relevance of using published raw data is discussed with respect to the Howells and Boas Immigrant datasets and the impact the dissemination of these resources has had on the discipline. Am J Phys Anthropol 145:163–167, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   

8.
Cys116, Lys240*, and Asp241* (asterisks indicate residues from the second subunit of the active dimer) at the active site of L-methionine γ-lyase of Pseudomonas putida (MGL_Pp) are highly conserved among heterologous MGLs. In a previous study, we found that substitution of Cys116 for His led to a drastic increase in activity toward L-cysteine and a decrease in that toward L-methionine. In this study, we examined some properties of the C116H mutant by kinetic analysis and 3D structural analysis. We assumed that substitution of Cys116 for His broke the original hydrogen-bond network and that this induced a significant effect of Tyr114 as a general acid catalyst, possibly due to the narrow space in the active site. The C116H mutant acquired a novel β-elimination activity and lead a drastic conformation change in the histidine residue at position 116 by binding the substrate, suggesting that this His residue affects the reaction specificity of C116H. Furthermore, we suggest that Lys240* is important for substrate recognition and structural stability and that Asp241* is also involved in substrate specificity in the elimination reaction. Based on this, we suggest that the hydrogen-bond network among Cys116, Lys240*, and Asp241* contributes to substrate specificity that is, to L-methionine recognition at the active site in MGL_Pp.  相似文献   

9.
10.
This paper contributes to the debate over the effectiveness of education policies in reducing overall health inequalities as compared to public health actions directed at the less-educated. Recentered Influence Function (RIF) regressions are used to decompose the contribution of education to the changing distribution of Body Mass Index (BMI) in France, between 1981 and 2003, into a composition effect (the shift in population education due to a massive educational expansion), and a structure effect (a changing educational gradient in BMI). Educational expansion has reduced overall BMI inequality by 3.4% for women and 2.3% for men. However, the structure effect on its own has produced a 10.9% increase in overall inequality for women, due to a steeper education gradient starting from the second quartile of the distribution. This structure effect on overall inequality is also large (7.6%) for men, albeit insignificant as it remains concentrated in the last decile. Educational expansion policies can thus reduce overall BMI inequalities; but attention must still be paid to the BMI gradient in education even for policies addressing overall rather than socioeconomic health inequalities.  相似文献   

11.
Native to North America, ruddy ducks Oxyura jamaicensis now occur in 21 countries in the western Palaearctic (including Iceland) and their expanding population threatens the native white-headed duck, Oxyura leucocephala, through hybridization and possibly competition for food and nest sites. We used mitochondrial DNA sequences and nuclear microsatellites to test whether the European ruddy duck population is descended solely from the captive population in the UK, which traces to seven individuals imported from the USA in 1948, or, alternatively, has been augmented by natural dispersal of birds from North America. Limited genetic diversity in the European population is consistent with a founder population as small as seven birds. In addition, shifts in allele frequencies at several loci, presumably due to genetic drift in the founding population, result in significant differentiation between the European and North American populations. Despite the recent separation of these populations, almost all individuals could be unambiguously assigned based on their composite genotypes, to one of two distinct populations, one comprising all of the European ruddy ducks we sampled (including those from Iceland and captive birds in the UK) and the other comprising all North American samples. Our results confirm that the European ruddy duck population is likely to derive solely from the captive population in the UK and we find no evidence of recent arrivals from North America or of admixture between ruddy ducks from Europe and North America.  相似文献   

12.
In the Late Pre-Roman Iron Age an underground granary in the village of Overbyg»rd was destroyed by fire and the contents were carbonised. Almost 2000 years later, analyses of the macroremains of the granary, which included a range of processed and unprocessed crops and weed seeds, showed that naked barley (Hordeum vulgare var. nudum) and bread wheat (Triticum aestivum s.l.) were the main crops cultivated, hulled barley (Hordeum vulgare) and flax (Linum usitatissimum) also played a role, whereas emmer (Triticum dicoccum) and gold of pleasure (Camelina sativa) were present as weeds or contaminants. The arable weed flora suggests that crops were sown in spring and that ecological conditions in the arable fields were very variable. The crops were harvested on the straw and may have spent some time drying and maturing in the fields before being transported home to be stored as severed ears in pest-proof granaries. Winnowing or, more probably, casting appears to have been used to clean the crop after threshing. It could not be ascertained if the crops had been sieved. Large collections of weed seeds in the granary were apparently the result of intentional gathering for food, rather than by-products of crop processing. In the light of the investigation it is suggested that future research into Iron Age agrarian practices should include both the analysis of archaeobotanical finds and a programme of practical experiments. This dual approach will give us a much better understanding of arable agriculture, not only in the Iron Age, but in prehistory as a whole.  相似文献   

13.
Dialectical Anthropology - Based on long-term ethnographic research, including documentary research, qualitative interviews and observations made at a Portuguese shelter for “sex trafficked...  相似文献   

14.

Background

Japanese encephalitis (JE) is very prevalent in China, but the incidence of JE among children has been greatly reduced by extensive promotion of vaccinations. The incidence of JE among adults, however, has increased in some parts of China.

Methods/Principal Findings

Data on JE in mainland China, in terms of incidence, gender, and age, were collected between 2004 and 2014. We conducted spatial and temporal analyses on data from different age groups. Generally, children aged 0–15 years still represent the major population of JE cases in China, despite the gradual decrease in incidence over years. However, the incidence of JE among adults in several provinces is notably higher than the national average, especially during the epidemic waves in 2006, 2009, and 2013. The JE cases in the 0–15-year-old group are distributed mainly in the area south of the Yangtze River, with peak incidence occurring from July to September. In the adult group, especially for those over 40 years old, the JE cases are concentrated mainly in the area north of the Yangtze River. JE incidence in the adult group in September and October is significantly greater compared to the other groups. Further analysis using Local Indicators of Spatial Association (LISA) reveals that the distribution of adult JE cases in the six provinces north of the Yangtze River, between north 30–35° latitude and east 110–130° longitude, is a hotspot for adult JE cases.

Conclusions/Significance

The rate of JE case increase for adults is much greater than for children and has become a public health issue. Therefore, studies on the necessity and feasibility of vaccinating adults who live in JE-endemic areas, but have never been vaccinated for JE, should become a new focus of JE prevention in the future.  相似文献   

15.
Most studies analysing the influence of socioeconomic deterioration on body size focus on the impact of food shortages and diseases on the growth in early childhood. To evaluate how socioeconomic conditions influence the growth during the adolescence, we tracked the body size of 15–19 year-olds over the last sixty years covering the socialist period (1951–1990), the war (1991–1995) and the transition to capitalistic economy. This study of Zagreb, Croatia, adolescent population provides information on the secular trend in height, weight and Body Mass Index (BMI) and examines their relation with Real Gross Domestic Product. From 1951 to 2010 the girls’ height approximately increased by 6.2 cm and weight by 6.8 kg, while the boys’ height increased by 12.2 cm and weight by 17.3 kg. Prior to 1991 mean BMI in girls was higher than in boys, but from 1991 on, the interrelation between the sexes has been opposite, possibly mirroring the cultural trends that started in mid-1970s and reflecting higher sensitivity of boys to the socioeconomic changes. In conclusion, the secular trend in body size over the investigated period reflects the positive economic trends interrupted by the war. The recent increase in BMI corresponds to the country's economic recovery and indicates the “nutrition transition”.  相似文献   

16.
Kolář  Jan  Kučerová  Andrea  Jakubec  Pavel  Vymazal  Jan 《Hydrobiologia》2017,794(1):347-358

Littorella uniflora (Plantaginaceae) is a scarce and declining aquatic plant in Europe. Its population has been strongly reduced by changes in fishpond management (eutrophication) in the Czech Republic since the 1950s. We studied its seed bank in both recent (n = 8) and historical localities (the last found from 1972 to 2000; n = 10) and tested the effects of sediment type and burial depth on seed germination using extracted seeds from two recent populations. The seeds were found in 60% of the historical localities, mostly in low densities (≤6 seeds per 3.75 l of sediment), and also in 100% of the recent localities in various densities (8–1390 seeds per 3.75 l of sediment); however, low germination rates (0–13.3%) were estimated. The seeds germinated best on wet filter paper, followed by nutrient-rich fishpond sediment, but poorly on sand mixed with different substrates. Burial depth significantly affected seed germination. The seeds germinated only on the soil surface and at the depth of 1 cm but no seed germinated at the depth of 3 and 5 cm. Besides low water transparency, both high rate of sediment accumulation and the absence of summer drainage may endanger L. uniflora populations in fishponds.

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17.
Metabolism of 25-hydroxyvitamin D3 (25-OH-D3) in pregnancy was investigated invitro in New Zealand White rabbits fed a rabbit chow. Kidney homogenates from pregnant mothers and fetuses were separately incubated with [3H]-25-OH-D3. The homogenates from fetuses produced significant amounts of [3H]-1α,25-dihydroxyvitamin D3 [1α,25-(OH)2-D3] from its precursor, while those from mothers predominantly produced [3H]-24,25-dihydroxyvitamin D3 [24,25-(OH)2-D3]. The identity of the radioactive metabolites produced from [3H]-25-OH-D3 was established by periodate cleavage and comigration with synthetic 1α,25-(OH)2-D3 or 24,25-(OH)2-D3 on high pressure liquid chromatography. These results clearly indicate that the fetal kidney is at least one of the sites of 1α,25-(OH)2-D3 synthesis in pregnancy.  相似文献   

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20.
Skull morphology results from the bone remodelling mechanism that underlies the specific bone growth dynamics. Histological study of the bone surface from Neanderthal mandible specimens of El Sidrón (Spain) provides information about the distribution of the remodelling fields (bone remodelling patterns or BRP) indicative of the bone growth directions. In comparison with other primate species, BRP shows that Neanderthal mandibles from the El Sidrón (Spain) sample present a specific BRP. The interpretation of this map allows inferences concerning the growth directions that explain specific morphological traits of the Neanderthal mandible, such as its quadrangular shape and the posterior location of the mental foramen.  相似文献   

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