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diesel and welding aerosols in an underground mine

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International Journal of Mining Science and Technology 2020年第4期30卷 449-454页

作者： Aleksandar d.Bugarski Teresa L.Barone jon A.Hummer National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

Researchers from the National Institute for Occupational Safety and Health(NIOSH)conducted a study in an isolated zone of an underground mine to characterize aerosols generated by:(1)a diesel-powered personnel carrier vehicle operated over a simulated light-duty cycle and(2)the simulated repair of existing equipment using manual metal arc welding(MMAW).Both the diesel-powered vehicle and MMAW process contributed to concentrations of nano and ultrafine aerosols in the mine *** welding process also contributed to aerosols with electrical mobility and aerodynamic mobility count median diameters of approximately 140 and 480 nm,*** welding particles collected on the filters contained carbon,iron,manganese,calcium,and aluminum.

关键词： diesel aerosols Welding aerosols Underground mining Size distribution

Application of Multi-well Subsidence Analysis of the Beryl Embayment,Viking Graben,Northern North Sea

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Acta Geologica Sinica(English Edition) 2006年第5期80卷 693-704页

作者： dOU Lirong jon d. TURNER Roger A. SCRUTTON China National Oil and Gas Exploration and development Corporation CNPC Beijing 100034 China department of Geology ＆ Geophysics The University of Edinburgh Edinburgh EH9 3JW Scotland UK

The Beryl Embayment is situated at the south end of the North Viking Graben in the North Sea. Three sets of normal faults, with N-S, NW-SE and NE-SW orientations, have been recognized in the Beryl Embayment. High-resolution subsidence analysis of 73 wells, combined with some seismic data, has been used to document Middle to Late Jurassic subsidence patterns in this area. The high temporal resolution achieved （1 to 2 million years per data point） has also allowed an assessment to be made of temporal evolution of faults with different orientations, and a study made of how and when the East Shetland Fault was linked and controlled sedimentary facies distributions. The results indicate that the East Shetland Fault can be divided into northern and southern parts which were linked together during the Early-Mid Oxfordian. The Mid-Late Jurassic syn-rift phase can be divided into four stages： minor active extension stage during the Bathonian-Middle Callovian, early syn-rotational stage during the Late Callovian-Early-Mid Oxfordian, syn-rotational climax stage during the Late Oxfordian-Early Volgian, and late syn-rotational stage during the Mid-Late Volgian. The results also show that there was a sequential variation of extension direction of active normal faults with different orientations, with an overall shift in the dominant orientation of active normal faults from N-S in the Bathonian-Middle Oxfordian, through NNW-SSE in the Late Oxfordian-Early Volgian （≈N30°E）, to NW-SE （≈N45°E） in the Mid-Late Volgian.

关键词： high-resolution subsidence analysis normal fault rift basin Beryl Embayment Viking Graben

PERIPHERAL MECHANISMS ANd MOdULATION IN INFLAMMATORY PAIN

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神经解剖学杂志 2001年第B7期17卷 39-40页

作者： jon d. LEVINE NIH Pain Center University of California San Francisco USA MD PhD

Recently there have been several major advances in our understanding of pathophysiological mechanisms in primary afferent nociceptors that may contribute to enhanced nociception (hyperalgesia) in response to injury, in a variety of clinical states. These include contributions of specific second messenger signaling pathways and ionic conductances. Important roles for specific second messenger systems in acute primary

关键词：炎症性疼痛调节外周机制电生理试验

Sperm speed is associated with sex bias of siblings in a human population

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Asian Journal of Andrology 2013年第1期15卷 152-154页

作者： Jim A Mossman jon Slate Tim R Birkhead Harry d Moore Allan A Pacey department of Ecology and Evolutionary Biology Box G Brown University Providence Rhode Island 02912 USA department of Animal and Plant Sciences University of Sheffield Western Bank Sheffield S10 2TN UK Centre for Stem Cell Biology Department of Biomedical Sciences University of Sheffield Western Bank Sheffield $10 2TN UK Academic Unit of Reproductive and developmental Medicine Department of Human Metabolism School of Medicine and Biomedical Sciences Sheffield $10 2SF UK

Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis, Markedly, fewer studies have investigated those risk factors that result in reduced sperm quality, such as poor sperm motility. The speed at which sperm swim is a major predictor of fertility and is extremely variable in human populations. It has been hypothesized that offspring sex may be adaptively manipulated to maximize the offspring＇s reproductive fitness （e.g., parents with genes for good male fertility traits, such as high sperm speed, would produce primarily sons and fewer daughters because the offspring will inherit advantageous male fertility genes）. Conversely, parents with poor male fertility genes would produce primarily daughters, We tested whether there was an association between how fast a man＇s sperm swam and the sex bias of his siblings in a sample of men attending clinic for fertility investigations with their partner and with a wide range of semen characteristics, including sperm speed. We found that the sex bias of a man＇s siblings is associated with his sperm speed; men with female-biased siblings had significantly slower sperm （judged using computer-assisted sperm analysis （CASA）） than men from male-biased sibships. This observation suggests family composition is an important factor that needs to be considered in future edidemiological and clinical studies of human fertility,

关键词： computer-assisted sperm analysis (CASA) fertility intralocus sexual conflict male offspring sex ratio sexual antagonism

Mafic Archean continental crust prohibited exhumation of orogenic UHP eclogite

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Geoscience Frontiers 2021年第5期12卷 411-420页

作者： Richard M.Palin James d.P.Moore Zeming Zhang Guangyu Huang jon Wade Brendan dyck department of Earth Sciences University of OxfordOxford OX13ANUnited Kingdom Earth Observatory of Singapore Nanyang Technological UniversitySingapore Institute of Geophysics SGEESVictoria University of WellingtonWellingtonNew Zealand Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China department of Earth Environmental and Geographical SciencesUniversity of British ColumbiaKelowna V1V 1V7Canada

The absence of ultrahigh pressure(UHP)orogenic eclogite in the geological record older than c.0.6 Ga is problematic for evidence of subduction having begun on Earth during the Archean(4.0-2.5 Ga).Many eclogites in Phanerozoic and Proterozoic terranes occur as mafic boudins encased within low-density felsic crust,which provides positive buoyancy during subduction;however,recent geochemical proxy analysis shows that Archean continental crust was more mafic than previously thought,having greater proportions of basalt and komatiite than modern-day ***,we show via petrological modelling that secular change in the petrology and bulk composition of upper continental crust would make Archean continental terranes negatively buoyant in the mantle before reaching UHP *** or delaminated Archean continental crust passes a point of no return during metamorphism in the mantle prior to the stabilization of coesite,while Proterozoic and Phanerozoic terranes remain positively buoyant at these *** orogenic eclogite may thus readily have formed on the Archean Earth,but could not have been exhumed,weakening arguments for a Neoproterozoic onset of subduction and plate ***,isostatic balance calculations for more mafic Archean continents indicate that the early Earth was covered by a global ocean over 1 km deep,corroborating independent isotopic evidence for large-scale emergence of the continents no earlier than c.3 *** findings thus weaken arguments that early life on Earth likely emerged in shallow subaerial ponds,and instead support hypotheses involving development at hydrothermal vents in the deep ocean.

关键词： Archean Eclogite Exhumation Secular change Geodynamics density

No trade-off between trichome production and tolerance to leaf and inflorescence damage in a natural population of Arabidopsis lyrata

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Journal of Plant Ecology 2014年第4期7卷 373-383页

作者： Adriana Puentes jonÅgren department of Plant Ecology and Evolution Evolutionary Biology Centre(EBC)Uppsala UniversityNorbyvägen 18DSE-75236 UppsalaSweden

Aims Early models of plant defense conceived resistance and tolerance to herbivore damage as mutually exclusive *** for this idea has been equivocal and studies on these two strategies are still needed to understand the evolution of defenses in natural *** Arabidopsis lyrata,the production of trichomes,a documented resistance trait,has been associated with a fitness cost in the absence of *** examined whether trichome production is also associated with reduced tolerance to simulated herbivore *** We conducted a field experiment in a natural swedish population of *** where we inflicted leaf(0 vs.50%of the area of each leaf removed)and inflorescence damage(0 vs.50%of inflores-cences removed)to trichome-producing and glabrous plants in a factorial *** examined the response(survival,growth and reproduction)of the plants to the imposed damage over 2 *** Findingstrichome-producing plants were not less tolerant than glabrous plants to simulated herbivore damage(no significant morph×leaf damage or morph×inflorescence damage interactions).Inflorescence and leaf damage had independent negative effects on the performance of damaged *** damage reduced rosette size the year of damage,but effects on reproductive output in the year of damage,and on survival and reproductive performance the following year were weak and not statistically *** damage significantly reduced the number of flowers,fruits and seeds the year of damage,but not in the following *** of morph,the study population was more tolerant to leaf than to inflorescence *** results indicated no trade-off between trichome production and tolerance,suggesting that these two defense mechanisms have the potential to evolve indepen-dently in this *** population.

关键词： plant defense fitness costs resistance traits defoliation florivory

Nuclear Phytochrome B Regulates Leaf Flattening through Phytochrome Interacting Factors

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Molecular Plant 2014年第11期7卷 1693-1696页

作者： Henrik Johansson jon Hughes department of Plant Physiology Justus Liebig University D35390 Giessen Germany

dear Editor, Plants are equipped with an array of photorecep- tors to measure UV-B, blue, red, and far-red light in order to monitor their light environment. However, although both synergistic and antagonistic interactions have been described between blue and red light signals （Casal, 2000）, little is known about how different light signals are inte- grated into modulate plant growth and development.

关键词： ARABIdOPSIS PHOTOTROPIN AUXIN PIF4 LIGHT

differences in characteristics of patients with and without known risk factors for hepatocellular carcinoma in the United States

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World Journal of Gastroenterology 2007年第5期13卷 781-784页

作者： jon d dorfman Richard Schulick Michael A Choti Jean-Francois H Geschwind Ihab Kamel Michael Torbenson Paul J Thuluvath department of Surgery The Johns Hopkins University School of Medicine Baltimore MD 21205 United States department of Radiology The Johns Hopkins University School of Medicine Baltimore MD 21205 United States department of Pathology The Johns Hopkins University School of Medicine Baltimore MD 21205 United States department of Medicine The Johns Hopkins University School of Medicine Baltimore MD 21205 United States

AIM： To examine the clinical characteristics of a subgroup of patients with hepatocellular carcinoma （HCC） and compare them to those with known risk factors. METHOdS： We used the HCC database of 306 patients seen at our institution from January 1, 1995 to december 31, 2001. Of the 306 patients, 63 （20%, group 1） had no known risk factors （hepatitis C virus, hepatitis B virus, alcohol, hemochromatosis or cirrhosis from any cause） and 243 （group 2） had one or more risk factors. RESULTS： The median age was similar in both groups, but there were disproportionate numbers of younger （〈 30 years old）, older （〉 80 years） patients, women （33% vs 18%）, and Caucasians （81% vs 52%） in group 1 as compared to group 2. There were fewer Asians （2% vs 11%） and African Americans （13% vs 27%） in group 1. Abdominal pain （70% vs 37%） was more common while gastrointestinal bleeding （0% vs 11%） and ascites （4% vs17%） were less common in group i compared to group 2. Group 1 had larger tumor burden （median size 9.4 cm vs 5.7 cm） at the time of presentation, but there were no differences in the site （right, left or bilateral lesions）, or number of tumors between the two groups. CONCLUSION： HCC patients without identifiable risk factors have different characteristics and clinical presentation compared to those with known risk *** of cirrhosis and larger tumor burden may explain the differences in the presenting symptoms.

关键词： Hepatocellular carcinoma Patient charaocteristics Risk factors

Electrons matter in ferromagnetic criticality

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Science Bulletin 2021年第14期66卷 1369-1371页

作者： Joe d.Thompson jon M.Lawrence Los Alamos National Laboratory Los AlamosNM 87545USA University of California IrvineCA 92697USA

When elemental iron is cooled from high temperatures,magnetic moments carried by its d-electrons begin a continuous transition to a state of parallel aligned moments below its Curie temperature T_(C)of about 1040 *** established in the mid-1900s,the statistical physics of this second order phase transition is universal,independent of the ordering temperature,material structure and chemical composition as well as the character of moment-bearing electrons.

关键词： transition 铁磁 character