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1.
The development of permanent premolar and molar teeth was examined in mandibular radiographs from wild sika deer (Cervus nippon) of known ages (74 males, 66 females, 4 unknown; age range 1–54 months) from Hyogo Prefecture. Tooth development was scored according to the method described by Brown & Chapman (1991a, b). Stage‐specific scores for all molar and premolar teeth were summed, and simple cubic regression analysis was used to analyse the relationship between the total score and age in months. Our analysis showed a strong cubic correlation between the total score and chronological age in months. The equation obtained from this analysis was used to estimate age within a 95% prediction interval in seven archaeological specimens from the Asahi archaeological site in central Japan. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

2.
黄山风景区客流波动的多时间尺度特征分析   总被引:1,自引:0,他引:1  
基于黄山风景区1987年1月至2010年12月的月度客流数据,运用TRAMO/SEATS方法和小波分析方法分析了黄山风景区客流的季节性变化和多时间尺度特征,结果表明:黄山风景区客流季节性变化显著,不仅存在月度波动性,而且季节性波动呈现年度变化性,客流淡季过长,淡季与平季、旺季落差过大是黄山风景区面临的经营难题;具有6个月、12个月、29个月和60个月不同时间尺度的周期变化,其中12个月的周期振荡最为明显,具有全域性;另外,6个月和12个月的时间特征尺度体现了黄山风景区客流由于季节性因素形成的年内季节性变化和年间的周期性变化,而29个月和60个月的时间特征尺度初步判断为由我国旅游业波动周期、景区外围区域经济周期和危机事件冲击影响共同作用所形成.最后,本文提出了一些对应性策略.  相似文献   

3.
The authors have completed structural and compositional analysis of Roman hydraulic concrete using large cores taken from a variety of maritime structures. In 2005 an 8 m3 block of hydraulic, pozzolanic concrete was built in the sea at Brindisi (Italy), applying the materials and procedures specified by the Roman architect Vitruvius. Cores were taken at 6 months and 12 months after construction and subjected to the same analyses as the first‐century bc cores from pilae associated with the Villa of the Domitii Ahenobarbi at Santa Liberata. Results show that a slight variation on the Vitruvian formula yields results closest to the Roman material, and that substantial curing requires 12 months.  相似文献   

4.
With regards to children who are born shortly before their mother's death (index), the cumulative proportion of survival up to 60 months of age was significantly lower (0.39 vs. 0.81) than those born just before the last child (penultimate) of the same mother. Such a difference is mainly due to high mortality in the first six months of age. Over the period between 1974 and 2005, survival improved among the penultimate but not the index children. For index children, the cumulative proportion of survival up to 60 months of age was significantly higher (0.79 vs. 0.51) if adopted by other households by the age of 15 days compared to those who stayed in their own households. Again for index children, the cumulative proportion of survival up to 60 months of age was significantly higher (0.82 vs. 0.70) for those who stayed in their own households where a grandmother was present compared to the presence of other female household members.  相似文献   

5.
This article examines the effects of abnormal floods on agricultural wages in Bangladesh. Drawing upon the district‐wise monthly real wage data for the period 1979–2000, it shows that wages decline sharply in the regions that are severely inundated for a long period of time. Wages may remain depressed in these regions even in the post‐flood months. However, wages increase in the flood months in the regions that remain submerged for short durations. The article examines the district‐wise crop yield data to explain these results in terms of the impact of flood on agricultural productivity, and therefore the demand for labour.  相似文献   

6.
Moisture transfer in the walls in direct contact with the ground leads to the migration of soluble salts, which are responsible for many building pathologies. The treatment of rising damp in historical heritage walls is a very complex procedure. The traditional techniques currently used to minimize rising damp are, in most cases, slight effective or too expensive, especially when dealing with walls of considerable thickness and/or heterogeneous materials such as the historical monuments. The main purpose of this work is to present the experimental results of the rising damp treatment conducted, over 3 years, in the Vilar de Frades Church, in northern Portugal, using the wall-base ventilation technology. The results showed that, for this particular climate conditions, the best solution is to operate seasonally, with outside air admitted to the system during summer months and inside air admitted to the system during winter months.  相似文献   

7.
The period July–September 1982 was the peak of geomagnetic activity during the 21st solar cycle. There were four very severe storms, which covered the strongest period of geomagnetic disturbances seen in recent years, namely the storms on 13/14 July, 7 August, 6/7 September and 21/22 September 1982. The present paper analyzes the corresponding ionospheric behaviour during these major magnetic storms, along with the storms that occurred around the local summer months during the preceding years within both hemispheres of the East Asia-Oceanian sector. It is shown that during the summer months in the low-latitudes and lower mid-latitudes of this sector the strong geomagnetic storms generally result in depletion of the ionospheric electron content and electron concentration at the F-region peak during both day-time and night-time. The situation in summer is quite different from other seasons and is basically unrelated to SSC time or/and maximum disturbance time and duration.  相似文献   

8.
The (30 mb) stratospheric temperatures at the North Pole during the winter months (November–February) showed large QBO (Quasibiennial Oscillations) but of an intermittent nature, different for different months and not matching in phase with the QBO of the tropical zonal wind. When the QBO was minimized by moving averages over two successive (yearly winter) values and then further over three successive values, the resultant series showed clear solar cycle variations with lags or leads of ~ (0–2) yr for temperature maxima with respect to sunspot maxima. However, in solar cycle 21 from 1978 onwards, temperatures seem to be more depressed, indicating enhanced stratospheric cooling in recent years, probably due to an increase of greenhouse gases. No relationship with El Nino events is indicated.  相似文献   

9.
Unusually large fontanelles were found in four skeletons of children from a cemetery in the North West Province of South Africa. These remains date from the last decade of the 19th and first half of the 20th century. Three small infants (two of about nine months, and one of about six months) and one child (of about three years) were affected. In the case of the three‐year‐old child pathologic changes were evident on the rest of the skeleton, which probably resulted in the delayed closure. The cause of the unusually large fontanelles in the other three individuals is less clear. Some possibilities are discussed, but it seems as though general hardship and malnutrition, congenital syphilis or other infectious diseases like rubella syndrome may be involved. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

10.
中外滑雪旅游的比较研究   总被引:6,自引:0,他引:6  
韩杰  韩丁 《人文地理》2001,16(3):26-30
本文就滑雪旅游历史进程、自然地理条件、滑雪地与滑雪场建设、客源市场状况等方面进行中外对比,旨在促进我国滑雪旅游业稳步、持续地发展。  相似文献   

11.
Abstract

An automated monitoring station, with climate sensors and a three-dimensional array of soil moisture sensors, was installed to document moisture-content changes in backfilled soil covering an Ancestral Pueblo an ‘great house’ at Chaco Culture National Historic Park, New Mexico, USA. The objective was to evaluate the performance of a geomembrane installation in the soil. Prior to its installation of the geomembrane, we observed that precipitation in winter and spring penetrated only 60–90cm into the fill during the first year after backfilling. A significant amount of moisture evaporated from the surface during the summer months, consequently the driest region was at the surface. In the following twenty-four months we observed continued dissipation of the trapped moisture towards the surface. The installation of the geomembrane system during the second year maintained a stable and dry soil environment, indicating effective surface removal of precipitation and preventing moisture penetration deeper into the soil.  相似文献   

12.
The determination of the kinematic parameters of travelling ionospheric disturbances (TIDs) is an essential basis for their physical understanding and investigation of their possible excitation mechanisms. This paper describes a method to determine these parameters on the basis of combined radio interferometric observations and measurements of differential Doppler shift observed for NNSS satellites.The analysis of Dutch interferometric and differential Doppler observations, based on this method, shows that the average direction of propagation of a sample of medium scale TIDs observed during the first three months of 1982 and 1983 is towards about 10° west of south; the speeds and horizontal ‘wavelengths’ are typical for medium scale TIDs. The results are in satisfactory agreement with those of similar research performed at Nançay (France) more than 4 yr later and using a different methodology, but not with results obtained at Nançay during the same winter months as used in the present study. Differences may indicate that TID parameters vary with geographic location and time.  相似文献   

13.
This article examines postwar British foreign policy by analysingthe decision-making process in Whitehall during the ‘deadlinecrisis’, the months between Khrushchev's ultimatum inNovember 1958 and Macmillan's famous voyage of discovery inFebruary 1959. The role played by the then British governmentduring this critical period of the Cold War was widely ignoreduntil the opening of the British archives for the late 1950sand early 1960s, under the thirty-year rule. Since then, scholarshave paid more attention to it. Diplomatic history is affectedgreatly by lack of access to public records; by utilizing previouslywithheld government documents, this paper results in a considerablereassessment of Britain's policy during the early cirisis months.Contrary to conventional wisdom, it argues that Macmillan'scontinuous attempts to shape alliance policy from behind thecurtain put alliance consensus at risk, provoked a deep breachof confidence and so diminshed his scope for effective actionseverely. His visit to Moscow did, in fact, achieve very little,if anything at all.  相似文献   

14.
15.
This article examines the response of a large Buddhist organization, Soka Gakkai, to the Tohoku earthquake and tsunami of March 2011. While this response was significant, it has not been reported in Japanese national news. An important question that is emerging for development agencies and academics as they look back over the response to the crisis, is how people possibly survived for the first few days and months, given that government aid did not reach some people for up to two months. This article highlights one significant early response and points to the problem of how to overcome the victim/helper dualism which is rooted in much failing NGO aid and development projects.  相似文献   

16.
Georg Simon Ohm's work in the field of electricity led to what is now considered to be the most fundamental law of electrical circuits, Ohm's Law. Much less known is that only months earlier, Ohm had published another law—one that differed significantly from the now accepted one. The latter entailed a logarithmic relation between the length of the conductor and a parameter that Ohm called “loss of force.” This paper discusses how Ohm came up with an initial law that he felt compelled to correct a few months later. We analyze Ohm's publication as well as his laboratory notes, relating them to our own laboratory experiences while using the replication method to study his work. We also discuss the conceptual background of Ohm's work. We conclude that he was significantly influenced by French studies in the field of electricity, most notably the ones by Charles Augustin Coulomb.  相似文献   

17.
The finding of a male red deer (Cervus elaphus L.) skeleton at Brandýs nad Labem (Central Bohemia, Czech Republic) dated to the Únětice culture (Early Bronze Age), radiocarbon dated to 1881–1679 cal BC (P 93 %), unique in the region, was analysed archaeozoologically. The depositing of a whole, unbutchered and entirely undamaged, but curled up body of a stag in a relatively small pit dug into the bottom of a large storage pit undoubtedly had some kind of special meaning or significance. It is interpreted as the burial of a ritually sacrificed beast. The deer male aged 2.5–3 years, with a withers height ca 129 cm, was in good health and had well-developed antlers. The stag most probably died between January and April, probably more towards the spring, but exactly how it died is unclear. The ritual appears to have been quite complex since it included a fire at the bottom of the storage pit. Deposition in a place designed for storage could suggest a ceremony relating to a sacrifice for prosperity and a good harvest. Despite a lack of evidence for the use of deer in rituals and the symbolic sphere during the Bronze Age, deer burials and the symbolic significance of the stag are known from other archaeological cultures and ethnicities. Interestingly, the entire foreleg of a younger red deer (aged 4–7 months), an isolated humerus of another young fawn (0.5–2 months) and the remains of two dog puppies (3.5–4.5 months) were present in upper horizons of the storage pit, which could also have a special meaning.  相似文献   

18.
The goal of the isotopic analysis of hair and nail from Puruchuco-Huaquerones is to reconstruct short term paleodiet using the stable isotopes of carbon and nitrogen in one centimetre increments of hair and two discrete points (distal and proximal) on the nail. This sampling method allows for the reconstruction of diet on a monthly basis (hair) and also diet at two periods (nail): four months and two weeks antemortem. The analysis of these two tissues demonstrates that diet varied from month to month and that food was not stored in any significant quantity. The patterning of the isotope data appears to be closely tied to the agricultural cycle, although a vertical economy cannot be rejected as an alternative explanation. Isotope data for both short (e.g., hair and nail) and long term diet (e.g., bone) are similar; this is interpreted as evidence for the continuity of the settlement in this area. There are no significant differences in the season of death between males or females or between the winter and summer months. The slightly higher mortality rate in the summer may be due to crop failure and subsequent food shortages.  相似文献   

19.
Two pyriform formations were identified within a bundle of linen bandages wrapping a 15–18 months old Early Dynastic mummy. The upper one was taken out of the bandages and examined to ascertain its nature.  相似文献   

20.
In August 1833, a party of American missionaries with their wives and children took up residence at Taiohae on Nukuhiva, one of the three islands that comprise the northern group of the Marquesas, only to abandon their station eight months later in April 1834. This paper looks at the journal records of those few months and considers the pressure that cross-cultural encounter placed on American notions of gender and the domestic ideology that underwrites it. Desperate to make a home in an alien land, the missionaries oversaw the construction of a residential compound but, as the months progressed, it became increasingly obvious that the walls they built were not secure. Far from being a place of respite, the compound was continuous with the native landscape and an indigenous sexual culture the missionaries could only register with disgust. Despite the best efforts of the female missionaries to model Christian family life, the peculiar domestic architecture of the mission dwellings formed not the desired proscenium between savage and civil but a more disorienting hall of mirrors in which Marquesan concepts of sexuality and space dissolved the distinction between public and private on which American notions of gender depended. Accordingly, the fate of the Marquesan mission allows us to revisit many of the critical commonplaces that circulate around women and Pacific missionary endeavour.  相似文献   

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