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Experimental and modeling Study of Forest Fire Effect on Soil thermal Conductivity

Pedosphere 2016年第4期26卷 462-473页

作者： Kathleen m.SmItS Elizabeth KIRBY William J.mASSmAN Larry Scott BAGGEtt Center for the Experimental Study of Subsurface Environmental Processes Department of Civil and Environmental EngineeringColorado School of Mines USDA Forest Service Rocky Mountain Research Station

An understanding of soil thermal conductivity after a wildfire or controlled burn is important to land management and post-fire recovery efforts. Although soil thermal conductivity has been well studied for non-fire heated soils, comprehensive data that evaluate the long-term effect of extreme heating from a fire on the soil thermal conductivity are limited. the purpose of this study was to evaluate the long-term impact of fire on the effective thermal conductivity of soils by directly comparing fire-heated and no-fire control soils through a series of laboratory studies. the thermal conductivity was measured for ten soil samples from two sites within the manitou Experimental Forest, Colorado, USA, for a range of water contents from saturation to the residual degree of saturation. the thermal conductivity measured was compared with independent estimates made using three empirical models from literature, including the Campbell et al. （1994）, CSt~ and Konrad （2005）, and massman et al. （2008） models. Results demonstrate that for the test soils studied, the thermal conductivity of the fire-heated soils was slightly lower than that of the control soils for all observed water contents. modeling results show that the Campbell et al. （1994） model gave the best agreement over the full range of water contents when proper fitting parameters were employed. Further studies are needed to evaluate the significance of including the influence of fire burn on the thermal properties of soils in modeling studies.

关键词： controlled burn degree of saturation empirical model water content wildfire

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Impact of residual zircon on Nd-Hf isotope decoupling during sediment recycling in subduction zone

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Geoscience Frontiers 2019年第1期10卷 241-251页

作者： Chen Zhang m.Santosh Qun Luo Shu Jiang Luofu Liu Dongdong Liu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing Basin and Reservoir Research Center China University of Petroleum Beijing Energy & Geoscience Institute University of Utah School of Earth Sciences and Resources China University of Geosciences Beijing Department of Earth Sciences University of Adelaide Unconventional Natural Gas Institute China University of Petroleum Beijing

the subduction factories in convergent plate margins exert crucial control on recycling terrestrial components and returning to the overlying crust. the Nd and Hf isotopic systems provide potential tracers to evaluate these processes. Here we present a case where these isotopic systems are decoupled in a suite of granites from the Chinese Altai, showing a wide range of εHf(t) values(from -4.7 to +10.8) in contrast to a limited range of εNd(t) values(from -5.8 to -1.9). the zircon xenocrysts occurring frequently in these rocks show markedly negative εHf(t) values(from -34.3 to -6.5) and positive d7 Li values(from +12.5 to +18.2). We propose a model to explain the observed relationship between residual zircon and Nde Hf isotope decoupling. We suggest that the Altai granites originated from partial melting of subducted slab components under relatively low temperature conditions which aided the residual zircon from oceanic sediments to inherit and retain a significant amount of177 Hf in the source, thereby elevating the^(176) Hf/^(177) Hf ratio of the melt, and decoupling from the^(143) Nd/^(144) Nd ratio during the subsequent magmatic processes. Our study illustrates a case where sediment recycling in subduction zone contributes to decoupling of Nd and Hf isotopic systems, with former providing a more reliable estimate of the source characteristics of granitic magmas.

关键词： Nd and Hf isotope systematics Subduction tectonics Oceanic sediment melting Geochemical recycling Chinese Altai

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Geochronology and geochemistry of mafic dykes in the Helanshan complex: Implications for mesozoic tectonics in the North China Craton

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Geoscience Frontiers 2018年第6期9卷 1711-1724页

作者： Zhenghui Li Xiaoming Liu Yunpeng Dong m.Santosh Feifei Zhang Jie Xu State Key Laboratory of Continental Dynamics Department of Geology Northwest University Department of Earth Sciences Western University(Canada) School of Earth Sciences and Resources China University of Geosciences (Beijing) Department of Earth Sciences University of Adelaide

the Helanshan tectonic belt(HtB) is a major tectonic divide between the Alxa and Ordos blocks in the North China Craton. the geochronology and petrogenesis of the mafic dykes in the northern HtB are keys to understanding the tectonic evolution of this belt. the mafic dykes, intruded into the Neoarchean-Paleoproterozoic metamorphic basement, are mainly composed of diabase with a mineral assemblage of plagioclase(45%-60%), pyroxene(25%-35%), minor quartz and Fe-ti oxides. the LA-ICPmS U-Pb analysis of zircon grains from representative dykes yield a weighted mean age of 206 ± 1.9 ma, which represents the crystallization age of the dyke. the diabases show high contents of Fe_2 O_3~t(11.88-17.55 wt.%), low contents of SiO_2(45.65-50.95 wt.%) and mgO(3.31-5.50 wt.%) with low mg#(=100×mgO/(mgO + FeO) atomic ration) of 33-44. they are characterized by enrichment of light rare earth elements(LREEs) and large ion lithophile elements(LILEs)(e.g., Rb, Ba and Pb), and slight depletion of high field strength elements(HFSEs). these features suggest that the magma has undergone extensive fractionation of olivine and pyroxene but only minor crustal contamination during its evolution. their high Sm contents and La/Sm ratios, and low Sm/Yb ratios indicate that magma from which the dykes formed was derived from low degree(about 5%) partial melting of an enriched garnet + spinel lherzolite mantle source. together with regional geology, these geochemical and geochronological data suggest that the mafic dykes in the HtB were formed in an intracontinental extensional setting during the late triassic.

关键词： mafic dykes Geochemistry Zircon UePb geochronology Hf isotope Helanshan tectonic Belt North China Craton

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接受按摩的早产新生儿的迷走神经兴奋性、胃蠕动和体重增加

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世界核心医学期刊文摘（儿科学分册） 2005年第12期1卷 32-33页

作者： Diego m.A. Field t. Hernandez-Reif m. 郭战宏 touch Research Institute University of Miami School of Medicine P.O. Box 016820 Miami FL 33101 United StatesDr.

multiple studies have documented an increase in weight gain after 5 to 10 days of massage therapy for preterm neonates. the massaged preterm neonates did not consume more calories than the control neonates. One potential mechanism for these effects might involve massage-induced increases in vagal activity, which in turn may lead to increased gastric motility and thereby weight gain. Study design: the present randomized study explored this potential underlying mechanism by assessing gastric motility and sympathetic and parasympathetic nervous system activity in response to massage therapy (moderate pressure) versus sham massage (light pressure) and control conditions in a group of preterm neonates. Results: Compared with preterm neonates receiving sham massage, preterm neonates receiving massage therapy exhibited greater weight gain and increased vagal tone and gastricmotility during and immediately after treatment. Gastric motility and vagal tone during massage therapy were significantly related to weight gain. Conclusion: the weight gain experienced by preterm neonates receiving moderate-pressure massage therapy may be mediated by increased vagal activity and gastricmotility.

关键词：早产新生儿迷走神经兴奋迷走神经张力按摩治疗副交感神经系统随机研究潜在机制研究设计

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生物活性土壤中的管道覆盖层性能评价

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油气储运 1997年第9期16卷 54-59页

作者： Jack t.R.Van Boven G. Wilmott m. Worthingham R.G. 辛勇中国石油天然气管道科学研究院

给出了聚乙烯缠带、FBE覆盖层和挤出聚乙烯覆盖层在空气、水、粘土、沙土环境中的剥离性能试验结果,提出了导致覆盖层损坏的原因,建立了覆盖层抗微生物降解性能的试验方法。采用埋在实际土壤后进行阴极剥离测试的方法对覆盖层性能进行... 详细信息

给出了聚乙烯缠带、FBE覆盖层和挤出聚乙烯覆盖层在空气、水、粘土、沙土环境中的剥离性能试验结果,提出了导致覆盖层损坏的原因,建立了覆盖层抗微生物降解性能的试验方法。采用埋在实际土壤后进行阴极剥离测试的方法对覆盖层性能进行了分级,对阴极剥离敏感性从大到小的顺序为FBE、挤出聚乙烯和聚乙烯缠带。阴极剥离试验证明:在埋入含有产酸(APB)和硫酸盐还原菌(SRB)的粘土后,覆盖层较易剥离。

关键词：管道覆盖层生物活性土壤防腐油气储运

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Heritability of Heart Rate Response to Arousals in twins

Heritability of Heart Rate Response to Arousals in Twins

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中国睡眠研究会第九届学术年会

作者： Xiaoling Gao Ali Azarbarzin Brendan t.Keenan michele Ostrowski Frances m.Pack Bethany Staley Greg maislin Allan I.Pack magdy Younes Samuel t.Kuna Department of medicine and Center for Sleep and Circadian Neurobiology University of Pennsylvania Department of Respiration The second Hospital of Shanxi Medical University Sleep Disorders Centre University of Manitoba

Study Objectives:to determine if the large and highly reproducible inter-individual differences in heart rate(HR) response to arousals during non-REm sleep arise from a heritable ***:Post-hoc analysis of polysomnograms of same-sex monozygotic and dizygotic twin ***:Academic medical center and Research and Development Laboratory(YRt Limited).Participants:55 monozygotic(mean[±SD]age 29.2±6.9 years;14 male and 41 female pairs) and 36dizygotic(mean age 26.217.5 years;15 male and 21 female pairs) twin pairs with a normal ***:None measurements and Results:Arousals were scored using the 2007 American Academy of Sleep medicine *** intensity was scaled(between 0 and 9) using an automatic algorithm based on the change in EEG time and frequency characteristics and a training data *** rate response to arousal(AHR) was determined and averaged at each arousal intensity per *** calculated the average arousal duration,average arousal intensity,average AHR,AHR at a given arousal intensity,rate of AHR per arousal intensity,and arousal intensity threshold of *** the classical approach to assess broad sense heritability(h),the arousal intensity threshold of AHR(h=0.94) and average arousal intensity(h=1.05) showed the strongest evidence for heritability after age and sex *** was supported by a maximum likelihood based variance components estimation approach,with h(95%CI) estimates of 0.38(0.13,0.62) for arousal intensity threshold of AHR and 0.64(0.48,0.80) for average arousal *** approach also suggested significant additive genetic effects for the number of arousals,average arousal duration,and the average ***:Genetic factors explain a significant fraction of the phenotypic variability for the threshold of AHR to arousal and average arousal *** also suggest that the number and duration of arousals and the average AHR may be heritable traits.

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male-like testosterone levels inhibit oviposition in a female parrot： A breeding experiment in budgerigars

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Current Zoology 2015年第4期61卷 586-595页

作者： Stefanie E. R LAHAYE marcel EENS Veerle m. DARRAS Rianne PINXtEN University of Antwerp Research Group Ethology Antwerp Belgium KU Leuven Laboratory of Comparative Endocrinology B-3000 Louvain Belgium

Studies in several songbird species have shown that treating females with the androgenic steroid hormone testoste- rone （t） can negatively affect female reproductive behaviors and breeding success. As the effects of t on females appear to be species-specific, it is not clear if similar effects of high t occur in non-songbird species. Here, we studied the effects of t supplementation on female reproductive behavior and oviposition in the budgerigar, melopsittacus undulatus, a small monogamous parrot species with distinct sex differences in parental behavior. We experimentally increased t concentrations to male-like levels in t-treated females compared to controls and we allowed females to breed. We found no significant effects of treatment on the latency to enter the nestbox but t treatment significantly interfered with oviposition. Our results show that t-treated females were seven times less likely to produce a clutch than control females. As we found that t treatment had a strong inhibitory effect on oviposition, our results indicate that female budgerigars suffer fitness costs from male-like plasma t levels. therefore, it may be possible that, also in non-songbird species, selection for higher t levels in males is constrained by a correlated response to selection which imposes fitness costs on females in terms of reproduction. Evaluating whether or not this is indeed the case requires further work combining different approaches to the study of the evolution of male and female testosterone levels [Current Zoology 61 （4）： 586-595, 2015].

关键词： Female testosterone Reproductive behavior melopsittacus undulatus Breeding success Intralocus sexual conflict Antagonistic selection

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评估采用陶瓷切削刀具加工等温淬火球墨铸铁的切削性能

评估采用陶瓷切削刀具加工等温淬火球墨铸铁的切削性能

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第一届国际机械工程学术会议

作者： Goldbeng m Smith G t Littlefair G Berry J t Southampton Institute UK-Systems Engineering Faculty Research Centre mississippi State University USA-Department of Mechanical Engineering

等温淬火球墨铸铁的制造技术在近30年来得到很大的提高,占据了世界范围黑色金属生产市场的相当大的比例。现在应用包括:航天、汽车、运输和重工业。等温淬火球墨铸铁是一个经热处理的铸铁,它具有突出的力学性能,如:高耐磨性、较长的疲... 详细信息

等温淬火球墨铸铁的制造技术在近30年来得到很大的提高,占据了世界范围黑色金属生产市场的相当大的比例。现在应用包括:航天、汽车、运输和重工业。等温淬火球墨铸铁是一个经热处理的铸铁,它具有突出的力学性能,如:高耐磨性、较长的疲劳寿命、突出的抗拉强度和延展性,给设计者和工程师们提供了吸引人的材料,代替传统用钢。目前,铸造是唯一的制造工艺,它能够开发利用这个材料,典型的铸件包括:曲轴、推土机、推土铲和齿轮。然而,采用硬质或高速钢刀具不能生产具有满意或优良的表面性能寿命的工具或者是由于这种材料的切削性能较差。因为这种材料具有马氏体组织。本文的调查研究已经被应用到等温淬火球墨铸铁部件的生产制造中。包括:使用陶瓷刀具进行切削加工,目的在于当提高切削速度和进刀速率时确定切削性能。本文还提供了等温淬火球墨铸铁基本性能的技术回顾,包括各种各样的优点:良好的力学性能,以及独特的铸造工艺。此外,回顾围绕着相关的陶瓷刀具的背景信息和实验工艺过程和所获得的结果。

关键词： Ceramic Cutting tools ADI

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Genetic basis for body size variation between an anadromous and two derived lacustrine populations of threespine stickleback Gasterosteus aculeatus in southwest Alaska

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Current Zoology 2016年第1期62卷 71-78页

作者： Ella BOWLES Rebecca A. JOHNStON Stevi L. VANDERZWAN Sean m. ROGERS Department of Biological Sciences University of Calgary 2500 University Dr. N.W. Calgary Alberta T2N 1N4Canada

Body size is a highly variable trait among geographically separated populations. Size-assortative reproductive isolation has been linked to recent adaptive radiations of threespine stickleback （Gasterosteus aculeatus） into freshwater, but the genetic basis of the commonly found size differ- ence between anadromous and derived lacustrine sticklebacks has not been tested. We studied the genetic basis of size differences between recently diverging stickleback lineages in southwest Alaska using a common environment experiment. We crossed stickleback within one anadromous （Naknek River） and one lake （Pringle Lake） population and between the anadromous and two lake populations （Pringle and JoJo Lakes）, and raised them in a salinity of 4-6 ppt. the F1 anadromous and freshwater forms differed significantly in size, whereas hybrids were intermediate or exhibited dominance toward the anadromous form. Additionally, the size of freshwater Fls differed from their wild counterparts, with within-population Fls from Pringle Lake growing larger than their wild counterparts, while there was no size difference between lab-raised and wild anadromous fish. Sexual dimorphism was always present in anadromous fish, but not in freshwater, and not always in the hybrid crosses. these results, along with parallel changes among anadromous and fresh- water forms in other regions, suggest that this heritable trait is both plastic and may be under di- vergent and/or sexual selection.

关键词： adaptation body size common garden genetic basis threespine stickleback.

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An Unusual and Fatal Case of Perthes’ Syndrome

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Open Journal of Pediatrics 2020年第3期10卷 515-520页

作者： F. B. Balde I. Oualil I. Sidibe t. mukenge A. mahmoudi m. Berdai K. Khatalla Y. Bouabdallah Department of Pediatric Surgery Hassan II Hospital and University Centre Fez Morocco mother and Child Resuscitation Service Hassan II Hospital and University Centre Fez Morocco

Perthes syndrome includes cervical and facial cyanosis, subconjunctival haemorrhage, petechial haemorrhages on the face, neck, and upper chest, secondary to chest compression. We report a clinical case of Perthes’ syndrome in 3-year-old boy victims of chest crush by a tractor. Clinical examination found: a Glasgow score at 13/15, polypnea, tachycardia, hypotension;wound of the occipital scalp, a low abundance of hematuria, deformation of the left lower limb. Body scan: bilateral pneumothorax and pulmonary contusions, left hemothorax;lacerations at the medial and upper renal pole grade IV, a low abundance of retroperitoneal hematoma, fracture of the left femur. Biological assessment showed major metabolic disturbances with severe acute rhabdomyolysis and multi-visceral failure. Without clinical improvement, the patient died after 36 hours of intensive care.

关键词： Perthes Syndrome traumatic Asphyxia Complications Lethal

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