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IGC 2004——Urbino International Workshop to discuss some new concepts in global tectonics

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Episodes 2005年第1期28卷 55-57页

作者： jan Passava GEOCHIM Courses Czech Geological Survey

In the context of the 32^nd International Geological Congress, the University of Urbino which is about to celebrate its 500^th anniversary hosted the post-Congress Workshop PWO-09 from 29^th to 31^st August 2004 dedicated to “New Concepts in Global Tectonics：Emphasis on Some Fundamental Questions in Geology”, convened and organized by Forese Carlo Wezel.

关键词： 2004年世界地质学大会地质构造学术成果成岩作用

Electrodynamics of Abrikosov vortices： the field theoretical formulation

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Frontiers of physics 2011年第4期6卷 357-369页

作者： Aron J. Beekman jan Zaanen Instituut-Lorentz for Theoretical Physics Universiteit Leiden P. O. Box 9506 2300 RA Leiden The Netherlands

Electrodynamic phenomena related to vortices in superconductors have been studied since their prediction by Abrikosov, and seem to hold no fundamental mysteries. However, most of the effects are treated separately, with no guiding principles. We demonstrate that the relativistic vortex worldsheet in spacetime is the object that naturally conveys all electric and magnetic information, for which we obtain simple and concise equations. Breaking Lorentz invariance leads to down-to-earth Abrikosov vortices, and special limits of these equations include for instance dynamic Meissner screening and the AC Josephson relation. On a deeper level, we explore the electrodynamics of two-form sources in the absence of electric monopoles, in which the electromagnetic field strength itself acquires the characteristics of a gauge field. This novel framework leaves room for unexpected surprises .

关键词： Abrikosov vortex, electromagnetism, Maxwell equations, differential geometry multivalued fields

Bright trions in direct-bandgap silicon nanocrystals revealed by low-temperature single-nanocrystal spectroscopy

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Light(Science & Applications) 2015年第1期4卷 179-186页

作者： Katerina Kusova Ivan Pelant jan Valenta Institute of Physics of the ASCR v.v.i.Cukrovarnicka 1016200 Prague 6Czech Republic Faculty of Mathematics and Physics Charles UniversityKe Karlovu 512116 Prague 2Czech Republic

Strain-engineered silicon nanocrystals(SiNCs)have recently been shown to possess direct ***,we report the observation of a rich structure in the single-nanocrystal photoluminescence spectra of strain-engineered direct-bandgap SiNCs in the temperature range of 9–300 *** relationship between individual types of spectra is discussed,and the numerical modeling of spectral diffusion of the experimentally acquired spectra reveals a common origin for most *** intrinsic spectral shape is shown to be a structure that contains three peaks,approximately 150 meV apart,each of which possesses a Si phonon *** spectral lines,reaching ≤ meV at 20 K,are *** observed temperature dependence of the spectral structure can be assigned to the radiative recombination of positively charged trions,in contrast to several previous reports linking a very similar shape to phonons in the surface capping *** result serves as strong additional support for the direct-bandgap nature of the investigated SiNCs.

关键词： direct bandgap low-temperature single-nanocrystal spectroscopy silicon nanocrystals trions

Debris Flows Risk Analysis and Direct Loss Estimation:the Case Study of Valtellina di Tirano,Italy

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Journal of Mountain Science 2014年第2期11卷 288-307页

作者： jan BLAHUT Thomas GLADE Simone STERLACCHINI Department of Engineering Geology Institute of Rock Structure and Mechanics Academy of Sciences of the Czech Republic Geomorphic Systems and Risk Research Group Department of Geography and Regional Research University of Vienna Institute for the Dynamic of Environmental Processes National Research CouncilCNR-IDPA

andslide risk analysis is one of the primary studies providing essential instructions to the subsequent risk management process. The quantification of tangible and intangible potential losses is a critical step because it provides essential data upon which judgments can be made and policy can be formulated. This study aims at quantifying direct economic losses from debris flows at a medium scale in the study area in Italian Central Alps. Available hazard maps were the main inputs of this study. These maps were overlaid with information concerning elements at risk and their economic value. Then, a combination of both market and construction values was used to obtain estimates of future economic losses. As a result, two direct economic risk maps were prepared together with risk curves, useful to summarize expected monetary damage against the respective hazard probability. Afterwards, a qualitative risk map derived using a risk matrix officially provided by the set of laws issued by the regional government, was prepared. The results delimit areas of high economic as well as strategic importance which might be affected by debris flows in the future. Aside from limitations and inaccuracies inherently included in risk analysis process, identification of high risk areas allows local authorities to focus their attention on the “hot-spots”, where important consequences may arise and local （large） scale analysis needs to be performed with more precise cost-effectiveness ratio. The risk maps can be also used by the local authorities to increase population’s adaptive capacity in the disaster prevention process.

关键词： Debris flows Risk analysis Economic losses Central Alps Italy

Dynamic Actin Controls Polarity Induction de novo in Protoplasts

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Journal of Integrative Plant Biology 2013年第2期55卷 142-159页

作者： Beatrix Zaban jan Maisch Peter Nick Botanical Institute Molecular Cell Biology Karlsruhe Institute of Technology

Cell polarity and axes are central for plant morphogenesis. To study how polarity and axes are induced de novo, we investigated protoplasts of tobacco Nicotiana tabacum cv. BY-2 expressing fluorescently- tagged cytoskeletal markers. We standardized the system to such a degree that we were able to generate quantitative data on the temporal patterns of regeneration stages. The synthesis of a new cell wall marks the transition to the first stage of regeneration, and proceeds after a long preparatory phase within a few minutes. During this preparatory phase, the nucleus migrates actively, and cytoplasmic strands remodel vigorously. We probed this system for the effect of anti-cytoskeletal compounds, inducible bundling of actin, RGD-peptides, and temperature. Suppression of actin dynamics at an early stage leads to aberrant tripolar cells, whereas suppression of microtubule dynamics produces aberrant sausage- like cells with asymmetric cell walls. We integrated these data into a model, where the microtubular cytoskeleton conveys positional information between the nucleus and the membrane controlling the release or activation of components required for cell wall synthesis. Cell wall formation is followed by the induction of a new cell pole requiring dynamic actin filaments, and the new cell axis is manifested as elongation growth perpendicular to the orientation of the aligned cortical microtubules.

关键词： Actin axis formation microtubules polarity induction tobacco BY-2 protoplasts.

Break of symmetry in regenerating tobacco protoplasts is independent of nuclear positioning

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Journal of Integrative Plant Biology 2016年第9期58卷 799-812页

作者： Linda Brochhausen jan Maisch Peter Nick Molecular Cell Biology Botanical Institute Karlsruhe Institute of Technology Katserstr. 2 D-76133 Karlsruhe Germany

Nuclear migration and positioning are crucial for the morphogenesis of plant cells. We addressed the potential role of nuclear positioning for polarity induction using an experimental system based on regenerating protoplasts, where the induction of a cell axis de novo can be followed by quantification of specific regeneration stages. Using overexpression of fluorescently tagged extranuclear （perinu- clear actin basket, kinesins with a calponin homology domain （KCH）） as well as intranuclear （histone H2B） factors of nuclear positioning and time-lapse series of the early stages of regeneration, we found that nuclear position is no prerequi- site for polarity formation. However, polarity formation and nuclear migration were both modulated in the transgenic lines, indicating that both phenomena depend on factors affecting cytoskeletal tensegrity and chromatin structure. We integrated these findings into a model where retrograde signals are required for polarity induction. These signals travel via the cytoskeleton from the nucleus toward targets at the plasma membrane.

关键词： Axis formation cytoskeleton nuclear migration polarity induction tobacco BY-2 protoplast

Endoscopic ultrasound-guided transrectal drainage of a pelvic abscess after Hinchey Ⅱ sigmoid colon diverticulitis: A case report

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World Journal of Clinical Cases 2023年第12期11卷 2848-2854页

作者： jan Drnovšek ŽanČebron jan Grosek Jurij janež Department of Gastroenterology University Medical Centre LjubljanaLjubljana 1000Slovenia Faculty of Medicine University of LjubljanaLjubljana 1000Slovenia Department of Abdominal Surgery University Medical Centre LjubljanaLjubljana 1000Slovenia

BACKGROUND Acute diverticulitis is one of the most prevalent complications of diverticular disease and may result in abscess formation, perforation, fistula formation, obstruction, or bleeding. Diverticular abscesses may be initially treated with antibiotics and/or percutaneous drainage and/or surgery. Endoscopic ultrasound(EUS)-guided drainage techniques are increasingly used as a minimally invasive alternative to percutaneous or surgical approaches, as they are associated with better treatment outcomes, shorter recovery time and duration of *** SUMMARY A 57-year-old female presented to the emergency department on account of abdominal pain and fever. Clinical examination revealed tenderness in the left lower abdominal quadrant, with elevated inflammatory markers in laboratory tests. Abdominal computed tomography(CT) revealed an 8 cm × 8 cm × 5 cm well-encapsulated abscess of the sigmoid colon, surrounded by numerous diverticula. A diagnosis of Hinchey Ⅱ diverticular abscess was made, and the patient was admitted and commenced on appropriate antibiotic treatment. A transrectal EUS showed a fluid collection in direct contact with the sigmoid colon. Transluminal drainage was performed, and a lumen-apposing metal stent was inserted into the abscess collection. A follow-up CT scan showed a regression of the collection. The patient’s general condition improved, and the stent was removed during a follow-up transrectal EUS that revealed no visible *** We report the first successful management of a pelvic abscess in patient with Hinchey Ⅱ acute diverticulitis using EUS-guided transluminal drainage in Slovenia. The technique appears effective for well-encapsulated intra-abdominal abscesses larger than 4 cm in direct contact with the intestinal wall of left colon.

关键词： Acute diverticulitis Diverticular disease Pelvic abscess Endoscopic drainage Case report

Hospital-based care for people living with HIV/AIDS in Ibadan,South Western Nigeria

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Asian Pacific Journal of Tropical Medicine 2009年第2期2卷 68-71页

作者： Olwookere SA Fatiregun aa Fayemi AF Department of Medicine State HospitalAsubiaroOsogboNigeria Department of Epidemiology Medical Statistics and Environmental HealthFaculty of Public HealthCollege of MedicineUniversity of IbadanIbadanNigeria Department of Medicine University College HospitalIbadanNigeria

Objective:To describe the pattern of admission-defining ailments and outcomes of care among people living with human immunodeficiency virus(HIV) /acquired immune deficiency syndrome(AIDS)(PLWHA) who presented for treatment at a tertiary health care institution in ***:We reviewed the hospital records of all patients admitted for AIDS and AIDS-related illnesses at the University College Hospital,Ibadan, Nigeria,from january 2005 to january ***:Seventy-two PLWHA were admitted during the study *** were 39 females(54.2%) and 33(45.8%) ***-seven(95%) PLWHA presented with *** 12(17%) were already receiving highly active antiretroviral therapy before *** -three patients(60%) commenced antiretroviral(ARV) therapy on ***-three patients(46%) had pulmonary tuberculosis,10(14%) had extrapulmonary tuberculosis,21(29.1%) had diarrhoea-related illnesses,20(28%) had anaemia,and nine(12.5%) presented with ***-nine patients(40.3%) were discharged home,and 43(59.7%) died before ***-nine patients(95.6%) were judged to be indigent,and required financial *** contributory causes of death included pulmonary tuberculosis in 21(48.8%),diarrhoeal diseases in five(11.6%),anaemia in five(11.6%),coma in nine(20.9%), and pneumonia in three(7.1%).Conclusion:Tuberculosis was the major admission-defining ailment among PLWHA.

关键词： Hospital Care Tuberculosis PLWHA

Sediment generation and soil mound denudation in areas of high-density tree throw along a river valley in the Jura Mountains, Switzerland

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Journal of Mountain Science 2021年第2期18卷 377-391页

作者： Philip GREENWOOD jan BAUER Nikolaus J KUHN Physical Geography&Environmental Change Research Group Department of Environmental SciencesUniversity of BaselKlingelbergstrasse 27Basel-4056Switzerland

A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous Jura region of northwest *** aims of the work were to assess sediment generation and annual sediment transport rates by tree throw on forested hillslopes,and to document surface hydrology characteristics on four fresh soil mounds associated with recent tree throws over a 24-day monitoring *** the soil mounds,average sediment recovery ranged from 7.7-28.2 g(dry weight),equivalent to a suspended sediment concentration of 145.2-327.8 g L^(-1),and runoff coefficients ranged from 1.0%-4.2%.Based on a soil bulk density value of 1,044 kg m^(-3),upslope runoff generation areas were denuded by an average 0.14 mm by the end of the 24-day monitoring period,representing an erosion rate equivalent to 2.1 mm yr^(-1).A ca.50 cm high soil mound could therefore feasibly persist for around 200-250 *** tree throw work,the dimensions of 215 individual tree throws were measured and their locations mapped in 12 separate locations along the river valley representing a cumulative area equivalent to 5.3 ha(***,43 per ha).Tree throws generated a total of 20.1 m^(3) of fine-sediment(<2 mm diameter),or the equivalent of 3.8×10^(-4) m^(3) m^(-2).The process of tree throw was originally attributed to two extreme weather events that occurred in west and central Europe in late December *** the 18-year period since both storms,this represents an annual sediment transport rate of 2.7×10^(-5) m^(3) m^(-1) yr^(-1).Exploring the relationship with wind on fall direction,65.5%of tree throws(143)generally fell in a downslope direction irrespective of hillslope aspect on which they were *** infers that individual storms may not have been responsible for the majority of tree throws,but instead,could be associated with root *** the high density of tree throws and their relative maturity(average age 41 years),we hypothesise that once tr

关键词： Tree throw Hillslope processes Sediment generation mechanism Sediment transport rate Soil mound Ibach river valley