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Effects of porosity heterogeneity on chemical dissolution-front instability in fluid-saturated rocks

Journal of Central South University 2017年第3期24卷 720-725页

作者： ZHAO Chong-bin peter SCHAUBS Bruce HOBBS Computational Geosciences Research Centre Central South University Changsha 410083 China CSIRO Mineral Resource National Research Flagship R O. Box 1130 Bentley WA 6102 Australia School of Earth and Environment The University of Western Australia Crawley WA 6009 Australia

Homogeneity and heterogeneity are two totally different concepts in *** the particle length scale,rocks exhibit strong heterogeneity in their constituents and *** the heterogeneity of porosity obeys the random uniform distribution,both the mean value and the variance of porosities in the heterogeneous porosity field can be used to reflect the overall heterogeneous characteristics of the porosity *** main purpose of this work is to investigate the effects of porosity heterogeneity on chemical dissolution front instability in fluid-saturated rocks by the computational simulation *** related computational simulation results have demonstrated that:1) since the propagation speed of a chemical dissolution front is inversely proportional to the difference between the final porosity and the mean value of porosities in the initial porosity field,an increase in the extent of the porosity heterogeneity can cause an increase in the mean value of porosities in the initial porosity field and an increase in the propagation speed of the chemical dissolution front.2) An increase in the variance of porosities in the initial porosity field can cause an increase in the instability probability of the chemical dissolution front in the fluid-saturated rock.3) The greater the mean value of porosities in the initial porosity field,the quicker the irregular morphology of the chemical dissolution front changes in the supercritical chemical dissolution *** means that the irregular morphology of a chemical dissolution front grows quicker in a porosity field of heterogeneity than it does in that of homogeneity when the chemical dissolution system is at a supercritical stage.

关键词： porosity heterogeneity chemical dissolution front instability computational simulation porous rocks

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Meiotic crossover： what controls the breaks？

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Asian Journal of Andrology 2011年第2期13卷 191-192页

作者： Katherine Ewen peter Boag Department of Growth and Reproduction RigshospitaletCopenhagen Denmark Department of Biochemistryand Molecular Biology Monash University ClaytonAustralia

Meiotic crossover （CO） formation establishes the physical linkagesbetween duplicated meiotic chromosomes. These COs are required for the segregation of chromosomes into the developing gametes and subsequent exchange of genetic material between maternal and paternal chromo- somes. Ultimately, meiotic CO recombination represents the fundamental advantage of sexual reproduction and helps drive genetic diversity.

关键词： Cobalt Chromosomes Histones Regulations Economic distribution

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From fundamental quantum optics to quantum information technology:the personal journey of Sir peter Knight

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Advanced Photonics 2021年第6期3卷 3-7页

作者： Xiaosong Ma peter Knight Nanjing University School of PhysicsNanjingChina the Physics Department at Imperial College the UK National Quantum Technology Programme Strategic Advisory Board the National Physical Laboratory Quantum Metrology Institute

Xiaosong Ma:What inspired you to choose quantum optics as your major when you were a student,and can you share your experience or research journey in this field?peter Knight:Quantum optics,as a discipline,was more or less formed during the time I’ve been active in the area.I started thinking about things that we would now call quantum optics in the middle of the 1960s when I was a student.

关键词： optics quantum Quantum

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Novel pharmacological strategies to prevent aortic complications in Marfan syndrome

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Journal of Geriatric Cardiology 2011年第4期8卷 254-257页

作者： peter Matt Friedrich Eckstein Division of Cardiac Surgery Basel University HospitalSpitalstrasse 21CH-4031 BaselSwitzerland

The Marfan syndrome(MFS)is a systemic connective tissue disorder caused by mutations in the FBN1 *** molecular studies,most performed in mouse models,revealed that the MFS is more a developmental abnormality with broad and complex effects on the morphogenesis and function of multiple organ ***1 haploinsufficiency and dysregulated transforming growth factor-beta(TGF-β)signaling seem to be critical for clinical manifestations in MFS including aortic root *** root aneurysm and aortic dissection represent the main causes of morbidity and mortality in *** importantly,TGF-βantagonism through angiotensin II type 1 receptor blockers(ARBs),for example losartan,has been shown to prevent and possibly reverse aortic root dilatation in a mouse model of MFS.A first human study on a small pediatric cohort confirmed those promising results in reducing the aortic root growth over a follow-up period of 12 to 47 ***,a large multicenter trial has been set up and results should be available *** therapeutic strategies which might be combined with losartan include traditionalβ-blockade,doxycyclin and *** management could offer the first potential for primary prevention of clinical manifestations in MFS.

关键词： Marfan syndrome aneurysm angiotensin receptor blocker

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Neuronal changes resulting in up-regulation of alpha-1 adrenoceptors after peripheral nerve injury

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Neural Regeneration Research 2014年第14期9卷 1337-1340页

作者： peter D.Drummond Centre for Research on Chronic Pain and Inflammatory Diseases Murdoch University Perth Western Australia Australia

Under normal conditions, the sympathetic neurotransmitter noradrenaline inhibits the production and release of pro-inflammatory cytokines. However, after peripheral nerve and tissue injury, pro-inflammatory cytokines appear to induce the expression of the alphalA-adreno- ceptor subtype on immune cells and perhaps also on other cells in the injured tissue. In turn, noradrenaline may act on up-regulated alphal-adrenoceptors to increase the production of the pro-inflammatory cytokine interleukin-6. In addition, the release of inflammatory mediators and nerve growth factor from keratinocytes and other cells may augment the expression of alphal-adrenoceptors on peripheral nerve fibers. Consequently, nociceptive afferents acquire an abnormal excitability to adrenergic agents, and inflammatory processes build. These mechanisms could contribute to the development of sympathetically maintained pain in conditions such as post-herpetic neuralgia, cutaneous neuromas, amputation stump pain and complex regional pain syndrome.

关键词： alphal-adrenoceptors up-regulation peripheral nerve injury nerve growth factor pro-inflammatory mediators complex regional pain syndrome

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P2X receptors in maintenance and differentiation of neural progenitor cells

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Neural Regeneration Research 2014年第23期9卷 2040-2041页

作者： Henning Ulrich peter Illes Departamento de Bioquímica Instituto de Química Universidade de Sao Paulo Rudolf-Boehm-Institut für Pharmakologie und Toxikologie der Universitat Leipzig

Purinergic receptors are among the first cell surface receptors expressed during embryonic development （Burnstock and Ulrich, 2011）. These are characterized based on their pharmacological properties of being activated by adenosine or purine/pyrimidine nucleotides as P1 and P2 receptors. P2 receptors are further classified by their structure as P2Y metabotropic and P2X ionotropic receptors.

关键词： P2X receptors in maintenance and differentiation of neural progenitor cells

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Volcanic Risk Perception and Coping Strategies from Mounts Cameroon and Nyiragongo Eruptions, Central Africa: A Comparative Analysis

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Journal of Geoscience and Environment Protection 2024年第6期12卷 161-189页

作者： Mabel N. Wantim Innocent Bradriyo Asong F. Zisuh Louis M. Balgawa Mero Yannah Katcho Karume Nde-Fon peter Bih Amban Nchini L. Wayih Emmanuel V. Yenshu Samuel N. Ayonghe Unit of Disaster Risk Management Department of Environmental Science University of Buea Buea Cameroon Observatoire Volcanologique de Goma (OVG) Goma Democratic Republic of the Congo Institute of Geological and Mining Research (IRGM) Yaounde Cameroon Faculty of Health Sciences University of Buea Buea Cameroon Faculty of Social and Management Sciences University of Buea Buea Cameroon

Approximately 2,000,000 people are exposed to volcanic risks in communities situated at the flanks of Mounts Cameroon (MC) and Nyiragongo (MN) volcanoes in Central Africa. This study therefore sought to investigate risk perception from four previous eruptions of MC, namely the 1959, 1982, 1999, and 2000 eruptions;and two previous eruptions of MN: 1977 and 2002. The study was initiated with co-design workshops held with major stakeholders in the cities of Buea and Goma at the flanks of MC and MN, respectively, in 2017, to develop the research objectives for the study. A non-random questionnaire survey was later conducted within 14 and 15 communities in Buea and Goma respectively, on the effects, perceived risks, and coping strategies for the chosen eruptions. Three age groups (18 - 30, 31 - 45 and >45 years) and gender (male and female) were considered. The population at the flanks of both volcanoes cited scientific and indigenous factors to be responsible for eruptions from these volcanoes. At MC and MN, ≥45% of the sampled participants (with a higher female population) perceived that the sampled eruptions posed a very high risk to the population. In terms of the effects, the age group of 18 - 30 was the least knowledgeable. In terms of direct effect on persons, over 90% of participants at MC and MN attested that they were overcome by fear/panic. On measures to cope with any likely eruption, the following order was established at the flanks of both volcanoes: sensitization of population, use of religious (prayers) and of traditional/indigenous strategies. In terms of future coping strategies, while the males at MC maintained sensitization as the favourite option, 62% of the males at MN opted for traditional/indigenous strategies. The female population at both MC and MN showed a higher preference for religious strategies like prayers.

关键词： Risk Perception Mount Cameroon Mount Nyiragongo Indigenous Buea Goma

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Semen analysis from an epidemiologic perspective

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Asian Journal of Andrology 2010年第1期12卷 91-94页

作者： Jens peter Ellekilde Bonde Department of Environmental and Occupational Medicine Copenhagen University Hospital Bispebjerg Bakke 23 2400Copenhagen NV Denmark

The fifth edition of the World Health Organization （WHO） manual for semen analysis includes for the first time reference values for human semen characteristics. This paper considers whether such values will help to resolve the intensely debated data indicating temporal and geographical shifts in sperm counts and hypotheses that anthropogenic activities that result in the release of chemicals into the environment are detrimental to male reproductive health. The reasons that these reference values will not fulfil these purposes are also explained. Although established reference values for semen characteristics are of limited value in analytical epidemiologic research, the WHO guidelines are of utmost importance for supporting the development of appropriate research protocols. Moreover, in spite of its limitations, semen analysis is still a useful research tool in epidemiological research, and no superior alternatives are on the horizon.

关键词： decline epidemiology reference values research semen analysis sperm counts

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One photon-per-bit receiver using near-noiseless phase-sensitive amplification

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Light(Science & Applications) 2020年第1期9卷 543-549页

作者： Ravikiran Kakarla Jochen Schroder peter A.Andrekson Photonics Laboratory Department of Microtechnology and Nanoscience(MC2)Chalmers University of Technology412-96 GothenburgSweden

Space communication for deep-space missions,inter-satellite data transfer and Earth monitoring requires high-speed data *** reach is fundamentally dictated by the available transmission power,the aperture size,and the receiver sensitivity.A transition from radio-frequency links to optical links is now seriously being considered,as this greatly reduces the channel loss caused by diffraction.A widely studied approach uses power-efficient formats along with nanowire-based photon-counting receivers cooled to a few Kelvins operating at speeds below 1 Gb/***,to achieve the multi-Gb/s data rates that will be required in the future,systems relying on pre-amplified receivers together with advanced signal generation and processing techniques from fibre communications are also *** sensitivity of such systems is largely determined by the noise figure(NF)of the pre-amplifier,which is theoretically 3 dB for almost all ***-sensitive optical amplifiers(PSAs)with their uniquely low NF of 0 dB promise to provide the best possible sensitivity for Gb/s-rate long-haul free-space ***,we demonstrate a novel approach using a PSA-based receiver in a free-space transmission experiment with an unprecedented bit-error-free,black-box sensitivity of 1 photon-per-information-bit(PPB)at an information rate of 10.5 Gb/*** system adopts a simple modulation format(quadrature-phase-shift keying,QPSK),standard digital signal processing for signal recovery and forward-error correction and is straightforwardly scalable to higher data rates.

关键词： receiver amplifier noise

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Synthetic biodegradable functional polymers for tissue engineering:a brief review

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Science China Chemistry 2014年第4期57卷 490-500页

作者： GUO BaoLin MA peter X Center for Biomedical Engineering and Regenerative Medicine Frontier Institute of Science and Technology Xi'an Jiaotong University Department of Biomedical Engineering University of Michigan Department of Biologic and Materials Sciences University of Michigan Macromolecular Science and Engineering Center University of Michigan Department of Materials Science and Engineering University of Michigan

Scaffolds play a crucial role in tissue engineering. Biodegradable polymers with great processing flexibility are the predominant scaffolding materials. Synthetic biodegradable polymers with well-defined structure and without immunological concerns associated with naturally derived polymers are widely used in tissue engineering. The synthetic biodegradable polymers that are widely used in tissue engineering, including polyesters, polyanhydrides, polyphosphazenes, polyurethane, and poly(glycerol sebacate) are summarized in this article. New developments in conducting polymers, photoresponsive polymers, amino-acid-based polymers, enzymatically degradable polymers, and peptide-activated polymers are also discussed. In addition to chemical functionalization, the scaffold designs that mimic the nano and micro features of the extracellular matrix(ECM) are presented as well, and composite and nanocomposite scaffolds are also reviewed.

关键词： synthetic biodegradable polymers functional polymers scaffolds tissue engineering

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