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101.
Land tenure rights reflect the deeper structures of society, particularly gender distinctions in relation to land. Considering the structural differences between patrilineal and matrilineal customary tenure systems in East Timor are understudied, this paper explores men and women’s experiences in accessing land under such arrangements. The comparative analysis of two patrilineal with one matrilineal land tenure systems in Ainaro and Manufahi districts suggests a significant degree of flexibility within both systems with respect to the norms of gendered inheritance. Therefore, the binary constructs of ‘patrilineal’ and ‘matrilineal’ societies are limiting. Both men and women in these communities may acquire land rights under different circumstances, mainly through negotiations with their parents or hamlet chief. Daughters in the patrilineal communities could inherit family land upon their parents’ death and sons in the matrilineal community could gain land by cultivating and maintaining unclaimed customary land. Empirical evidence show that inheritance principally determines usufruct rights to land, but marriage exchange practices complicates a deeper understanding of traditional East Timorese land rights.
Pyone Myat ThuEmail:
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102.
The matrix of the C2-ungrouped Tarda meteorite contains abundant smectite minerals that swell and crumble when exposed to polar liquids, causing the sample to rapidly slake. This phenomenon presents a serious challenge when polishing the meteorite, as common polishing liquids used on carbonaceous chondrites, such as water, ethanol, ethylene glycol, and isopropyl alcohol, are polar and will cause the sample to swell, making it unsuitable for some analyses. Hexane and mineral oil are nonpolar liquids that were found to not induce swelling on highly expansive montmorillonite-clay analog material and were effectively integrated into a polishing procedure for Tarda. Here, we detail a procedure for mounting, cutting, and polishing the Tarda meteorite to prepare a surface that is suitable for a variety of sensitive techniques, such as electron microprobe analysis. This work offers a practical methodology for the preparation of other clay-rich samples, which may include the recently returned Ryugu and Bennu materials.  相似文献   
103.
Entanglement in marine debris is a contributing factor in Steller sea lion (SSL; Eumetopias jubatus) injury and mortality. We quantified SSL entanglement by debris type, sex and age class, entanglement incidence, and estimated population level effects. Surveys of SSL haul-outs were conducted from 2000-2007 in Southeast Alaska and northern British Columbia. We recorded 386 individuals of all age classes as being either entangled in marine debris or having ingested fishing gear. Packing bands were the most common neck entangling material (54%), followed by rubber bands (30%), net (7%), rope (7%), and monofilament line (2%). Ingested fishing gear included salmon fishery flashers (lures: 80%), longline gear (12%), hook and line (4%), spinners/spoons (2%), and bait hooks (2%). Entanglement incidence was 0.26% (SD = 0.0064, n = 69 sites). “Lose the Loop!” Simple procedures such as cutting entangling loops of synthetic material and eliminating the use of packing bands can prevent entanglements.  相似文献   
104.
Optically stimulated luminescence dating of Late Quaternary glaciogenic sediments was undertaken in critical areas of the Himalayas of northern Pakistan in order to examine the timing of glaciation. The dates demonstrate that several glaciations occurred during the last glacial cycle. In Swat, the Grabral 2 Stade and the Kalam I Stade were dated at ca. 77 ka and ca. 38 ka, respectively. The error on the former date is large and it is conceivable that the moraines may have formed during the early part of Oxygen Isotope Stage 3 rather than during Oxygen Isotope Stage 4. The Kalam I Stade, however, clearly represents a glaciation during Oxygen Isotope Stage 3. The oldest moraines and those at the lowest altitude in the Indus valley at Shatial have an age of ca. 60 ka. These also relate to a major glacial advance during Oxygen Isotope Stage 3. A younger series of moraines, the Jalipur Tillite, and glaciofluvial sands at Liachar in the Indus valley, and moraines at Rampur–Tarshing have ages of ca. 27 ka, ca. 21–23 ka and ca. 15 ka, respectively. These dates show that glaciers also occupied parts of the Indus valley during Oxygen Isotope Stage 2. These dates and the morphostratigraphy show that glaciation in the Pakistani Himalaya was more extensive during the early part of the last glacial cycle and that the local last glacial maximum in Pakistan was asynchronous with the maximum extent of Northern Hemisphere ice sheets. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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Sand beach ridges are considered to be derived either from aeolian processes and/or waves but their deposition by individual or multiple storms has not been investigated in any detail. We use numerical meteorological and oceanographic models to determine the origin of a sequence of 29 shore parallel sand beach ridges in northeastern Australia. The results suggest that the ridges were constructed by waves and that the final form or height of the ridges is a function of high-energy tropical cyclone generated waves plus storm tides. Hence these landforms archive a nearly 6000 year long history of intense tropical cyclones. The record implies that these extreme tempests occur considerably more frequently than that suggested by the short historical record for this region. The genesis of this sand beach ridge plain has implications for the interpretation of similar sequences elsewhere along the northeast coast of Australia and in comparable environments globally. If other similar sand beach ridge plains have also been deposited by like processes it stands to reason that these long-term records of high intensity tropical cyclones can be used to ascertain a regional scale risk assessment from this hazard.  相似文献   
107.
We examined aluminosilicate glasses containing a variety of network modifying to intermediate cations (Li, La, Sc, and Fe), quenched from melts at 1 atm to 8 GPa, to further investigate the role of cation field strength in Al coordination changes and densification. 27Al Nuclear Magnetic Resonance Spectroscopy (NMR) reveals that the mean Al coordination increases with increasing pressure in the Li-containing glasses, which can be explained by a linear dependence of fractional change in Al coordination number on cation field strengths in similar K-, Na-, and Ca-containing aluminosilicate glasses (K < Na < Li < Ca). Measured recovered densities follow a similar linear trend. In contrast, the La-containing glasses have significantly lower mean Al coordination numbers at given pressures than the cation field strength of La and glass density would predict. La L3 X-ray absorption fine structure (XAFS) spectroscopy results indicate a significant increase with pressure in average La-O bond distances, suggesting that La and Al may be “competing” for higher coordinated sites and hence that both play a significant role in the densification of these glasses, especially in the lower pressure range. However, in Na aluminosilicate glasses with small amounts of Sc, 45Sc NMR reveals only modest Sc coordination changes, which do not seem to significantly affect the mean Al coordination values. For a Li aluminosilicate glass, 17O MAS and multiple quantum magic angle spinning (3QMAS) NMR data are consistent with generation of more highly coordinated Al at the expense of non-bridging oxygen (NBO), whereas La aluminosilicate glasses have roughly constant O environments, even up to 8 GPa. Finally, we demonstrate that useful 23Na and 27Al MAS NMR spectra can be collected for Ca-Na aluminosilicate glasses containing up to 5 wt.% Fe oxide. We discuss the types of structural changes that may accompany density increases with pressure and how these structural changes are affected by the presence of different cations.  相似文献   
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Recently, mode converted shear waves (C‐waves) have been shown to enable overpressure prediction in media where primary wave acquisition is inhibited by gas and fluid effects – C‐wave moveout is analysed and a long standing relationship between differential stress and primary‐wave (P‐wave) velocity is modified and employed. Though pore‐pressure prediction based on C‐waves is supported by empirical evidence from laboratory and field experiments, a theoretical justification has yet to be developed. In this research note, we provide a supporting algebra for the original relationship between pore pressure and C‐wave velocity.  相似文献   
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