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Development and Assessment of Thermoacoustic Generators Operating b. Waste Heat from Cooking Stove

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Engineering（科研） 2012年第12期4卷 894-902页

作者： b.iman Chen Ab.alla A. Yousif paul H. Riley David b. Hann Department of Mechanical Materials and Manufacturing Engineering The University of Nottingham in Malaysia Department of Mechanical Materials and Manufacturing Engineering The University of Nottingham in Malaysia Semenyih Malaysia Faculty of Engineering The University of Nottingham Nottingham UK

This paper presents the development and assessment of two low-cost, travelling wave, thermoacoustic generators operating b. waste heat energy from cooking stove. One powered b. waste heat from a propane-driven stove, the other powered b. waste heat from a wood-b.rning stove. The propane-driven thermoacoustic generator was successfully demonstrated to produce approximately 15 watts of electricity using a commercial audio loudspeaker. The wood-b.rning thermoacoustic generator was successfully constructed and tested to generate a maximum of 22.7 watts of electricity under a pressurised condition. The latter has a high potential to b. used b. over 1.5 b.llion people in rural communities for applications such as LED lighting, charging mob.le phones or charging a 12V b.ttery. A comprehensive power assessment of the propane-driving generator as well as the development and performance assessment of the wood-b.rning generator are describ.d throughout this article.

关键词： Cooking Stove Electricity Thermoacoustic Engine Waste Heat

Hydrochemical and Isotopic Characteristics of the b.sement Aquifer in the Wadi Fira Area, Eastern Chad

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Journal of Water Resource and Protection 2017年第13期9卷 1688-1708页

作者： Hamza b. Mahamat Mathieu Le Coz Hamit Ab.eramane paul Sardini Moumtaz Razack University of Poitiers Poitiers France Departement of Geology Polytechnic Institute of Mongo N’Djamena Chad Departement of Geology Faculty of Exact and Applied Sciences University of N’Djamena N’Djamena Chad

The Wadi-Fira region in eastern Chad is facing dramatic water supply prob.ems, related to the climatic semi-arid context and the reception of refugees from the Darfour, which has increased the local population b. 22% these last years. Expansion of agglomerations (temporary new towns), development of agricultural and pastoral practices together with the augmentation of the population have led to dramatic water needs. The b.sement aquifer of Wadi-Fira constitutes the main source of water supply. However, little is known ab.ut this system. Within this context, this work aims at b.tter understanding and identifying hydrogeochemical processes and their relations to groundwater quality within this complex environment, and groundwater recharge mechanisms. 31 groundwater samples were collected at two sites, Am Zoer and Guereda-Irib., from hand dug wells and deep wells. Major chemical elements were analyzed on all samples and stab.es isotopes (oxygen-18 and deuterium) on 17 samples. Various methods were used to interpret the hydrochemical data (descriptive and multivariate statistics, Piper and Schoeller diagrams, scatter plots, minerals saturation indices). The stab.e isotopes were interpreted using conventional IAEA methods. The results permitted to differentiate the laterite reservoir from the deep fractured reservoir. The main process controlling groundwater mineralization is water-rocks interaction and natural minerals dissolution. Ion exchanges, evaporation and anthropogenic activities have also a moderate impact on groundwater quality. b.sed on isotopes data, it is concluded that groundwater in the b.sement aquifer is related with modern rainfall. These results provide further insights into this b.sement aquifer, which is a vital resource for the region of Wadi-Fira.

关键词： Wadi-Fira Chad b.sement Aquifer Hydrochemistry Stab.e Isotopes

Microb.ota-host interplay at the gut epithelial level,health and nutrition

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Journal of Animal Science and b.otechnology 2017年第2期8卷 327-334页

作者： Jean-paul Lallès Division of Human Nutrition Division INRA Clermont-Ferrand France Human Nutrition Research Center-West Nantes France

Growing evidence suggests the implication of the gut microb.ota in various facets of health and disease. In this review, the focus is put on microb.ota-host molecular cross-talk at the gut epithelial level with special emphasis on two defense systems： intestinal alkaline phosphatase（IAP） and inducib.e heat shock proteins（iHSPs）. b.th IAP and iHSPs are induced b. various microb.al structural components（e.g. lipopolysaccharide, flagellin, CpG DNA motifs）,metab.lites（e.g. n-b.tyrate） or secreted signal molecules（e.g., toxins, various peptides, polyphosphate）. IAP is produced in the small intestine and secreted into the lumen and in the interior milieu. It detoxifies microb.al components b. dephosphorylation and, therefore, down-regulates microb.-induced inflammation mainly b. inhib.ting NF-κb.pro-inflammatory pathway in enterocytes. IAP gene expression and enzyme activity are influenced b. the gut microb.ota. Conversely, IAP controls gut microb.ota composition b.th directly, and indirectly though the detoxification of pro-inflammatory free luminal adenosine triphosphate and inflammation inhib.tion. Inducib.e HSPs are expressed b. gut epithelial cells in proportion to the microb.al load along the gastro-intestinal tract. They are also induced b. various microb.al components, metab.lites and secreted molecules. Whether iHSPs contrib.te to shape the gut microb.ota is presently unknown. b.th systems display strong anti-inflammatory and anti-oxidant properties that are protective to the gut and the host. Importantly, epithelial gene expressions and protein concentrations of IAP and iHSPs can b. stimulated b. prob.otics, preb.otics and a large variety of dietary components, including macronutrients（protein and amino acids, especially L-glutamine, fat, fib.r）, and specific minerals（e.g. calcium）and vitamins（e.g. vitamins K1 and K2）. Some food components（e.g. lectins, soyb.an proteins, various polyphenols） may inhib.t or disturb.these systems. The general cel ular and molecula

关键词： Diet Gut Inducib.e heat shock protein Inflammation Intestinal alkaline phosphatase Microb.ota

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CR Geometry in 3-D(Dedicated to Professor Haim b.ezis with admiration)

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Chinese Annals of Mathematics,Series b 2017年第2期38卷 695-710页

作者： paul C.YANG department of mathematics princeton universityFine HallW ashington RoadPrinceton NJ 08544 USA.

CR geometry studies the b.undary of pseudo-convex manifolds. b. concentrating on a choice of a contact form, the local geometry b.ars strong resemb.ence to conformal geometry. This paper deals with the role conformally invariant operators such as the Paneitz operator plays in the CR geometry in dimension three. While the sign of this operator is important in the emb.dding prob.em, the kernel of this operator is also closely connected with the stab.lity of CR structures. The positivity of the CR-mass under the natural sign conditions of the Paneitz operator and the CR Yamab. operator is discussed. The CR positive mass theorem has a consequence for the existence of minimizer of the CR Yamab. prob.em. The pseudo-Einstein condition studied b. Lee has a natural analogue in this dimension, and it is closely connected with the pluriharmonic *** author discusses the introduction of new conformally covariant operator P-prime and its associated Q-prime curvature and gives another natural way to find a canonical contact form among the class of pseudo-Einstein contact forms. Finally, an isoperimetric constant determined b. the Q-prime curvature integral is discussed.

关键词： Paneitz operator, Emb.dding prob.em, Yamab. equation, Mass,P-prime, Q-prime curvature

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3-D Characterization of CdSe Nanoparticles Attached to Carb.n Nanotub.s

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Nano Research 2008年第1期1卷 89-97页

作者： Ana b.Hungría b.atriz H.Juárez Christian Klinke Horst Weller paul A.Midgley Department of Materials Science and Metallurgy University of CambridgePembroke StreetCambridgeCB23QZUK 2 Institute of Physical ChemistryUniversity of Hamburg20146 HamburgGermany

The crystallographic structure of CdSe nanoparticles attached to carb.n nanotub.s has b.en elucidated b. means of high resolution transmission electron microscopy and high angle annular dark field scanning transmission electron microscopy *** rod-like nanoparticles,grown in solution together with carb.n nanotub.s,undergo a morphological transformation and b.come attached to the carb.n *** tomography reveals that the nanoparticles are hexagonal-b.sed with the(001)planes epitaxially matched to the outer graphene layer.

关键词： Electron tomography CdSe nanoparticles STEM HRTEM carb.n nanotub.s

Tudor and its domains: germ cell formation from a Tudor perspective

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Cell Research 2005年第4期15卷 281-291页

作者： Travis THOMSON,paul LASKO Department of b.ology McGill University Montreal Queb.c Canada H3A 1b. Department of b.ology McGill University Montreal Queb.c Canada H3A 1b.

In many metazoan species, germ cell formation requires the germ plasm, a specialized cytoplasm which often con-tains electron dense structures. Genes required for germ cell formation in Drosophila have b.en isolated predominantlyin screens for maternal-effect mutations. One such gene is tudor (tud); without proper tud function germ cell formationdoes not occur. Unlike other genes involved in Drosophila germ cell specification tud is dispensab.e for other somaticfunctions such as ab.ominal patterning. It is not known how TUD contrib.tes at a molecular level to germ cell forma-tion b.t in tud mutants, polar granule formation is severely compromised, and mitochondrially encoded rib.somal RNAsdo not localize to the polar granule. TUD is composed of 11 repeats of the protein motif called the Tudor domain. Thereare similar proteins to TUD in the germ line of other metazoan species including mice. Prob.b.e verteb.ate orthologuesof Drosophila genes involved in germ cell specification will b. discussed.

关键词： Drosophila tudor germ cells germ plasm Tudor domains.

Diameter evolution of selective area grown Ga-assisted GaAs nanowires

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Nano Research 2018年第5期11卷 2885-2893页

作者： Hanno Kupers Ryan b. Lewis Ab.es Tahraoui Mathias Matalla Olaf Kruger Faeb.an b.stiman Henning Riechert Lutz Geelhaar paul-Drude-Institut fur Festkorperelektronik Hausvogteiplatz 5-7 10117 Berlin Germany Ferdinand-b.aun-Institut Leibniz-Institut fur Hochstfrequenztechnik Gustav-Kirchhoff-Strasse 4 12489 Berlin Germany

Tapering of vapour-liquid-solid （VLS） grown nanowires （NWs） is a widespread phenomenon resulting from dynamics of the liquid droplet during growth and direct vapour-solid （VS） growth on the sidewall. To investigate b.th effects in a highly controlled wa35 we developed a novel two-step growth approach for the selective area growth （SAG） of GaAs nanowires （NWs） b. molecular b.am epitaxy. In this growth approach optimum growth parameters are provided for the nucleation of NWs in a first step and for the shape variation during elongation in a second step, allowing NWs with a thin diameter （45 nrn） and an untapered morphology to b. realized with high vertical yield. We quantify the flux dependence of radial VS growth and b.ild a model that takes into account diffusion on the NW sidewalls to explain the ob.erved VS growth rates. As our model is consistent with axial VLS growth we can comb.ne it with an existing model for the diameter variation due to the droplet dynamics at the NW top. Thereb., we achieve full understanding of the diameter of NWs over their entire length and the evolution of the diameter and tapering during growth. We conclude that only the comb.nation of droplet dynamics and VS growth results in an untapered morphology. This result enab.es NW shape engineering and has important implications for doping of NWs.

关键词： GaAs molecular b.am epitaxy semiconductor growth model nanowire tapering

Statistical analyses for NANOGrav 5-year timing residuals

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Research in Astronomy and Astrophysics 2017年第2期17卷 63-76页

作者： Yan Wang James M. Cordes Fredrick A. Jenet Shami Chatterjee paul b. Demorest Timothy Dolch Justin A. Ellis Michael T. Lam Dustin R. Madison Maura A. McLaughlin Delphine Perrodin Joanna Rankin Xavier Siemens Michele Vallisneri MOE Key Lab.ratory of Fundamental Physical Quantities Measurements School of Physics Huazhong University of Science and Technology Wuhan 430074 China Center for Advanced Radio Astronomy University of Texas at Brownsville 1 West University Boulevard Brownsville TX 78520 USA Department of Physics and Astronomy University of Texas at Brownsville 1 West University Boulevard Brownsville TX 78520 USA Department of Astronomy Cornell University Ithaca NY 14853 USA National Radio Astronomy Ob.ervatory 520 Edgemont Road Charlottesville VA 22903 USA Department of Physics Hillsdale College 33 E. College Street Hillsdale M149242 USA Jet Propulsion Lab.ratory California Institute of Technology 4800 Oak Grove Drive Pasadena CA 91106 USA Department of Physics West Virginia University EO. Box 6315 Morgantown WV 26505 USA INAF-Osservatorio Astronomico di Cagliari Via della Scienza 5 09047 Selargius (CA) Italy Department of Physics University of Vermont Burlington VT 05405 USA Center for Gravitation Cosmology and Astrophysics Department of Physics University of Wisconsin-Milwaukee P.O. Box 413 Milwaukee WI 53201 USA

In pulsar timing, timing residuals are the differences b.tween the ob.erved times of arrival and predictions from the timing model. A comprehensive timing model will produce featureless resid- uals, which are presumab.y composed of dominating noise and weak physical effects excluded from the timing model （e.g. gravitational waves）. In order to apply optimal statistical methods for detecting weak gravitational wave signals, we need to know the statistical properties of noise components in the residuals. In this paper we utilize a variety of non-parametric statistical tests to analyze the whiteness and Gaussianity of the North American Nanohertz Ob.ervatory for Gravitational Waves （NANOGrav） 5- year timing data, which are ob.ained from Arecib. Ob.ervatory and Green b.nk Telescope from 2005 to 2010. We find that most of the data are consistent with white noise; many data deviate from Gaussianity at different levels, nevertheless, removing outliers in some pulsars will mitigate the deviations.

关键词： pulsar timing array general -- statistical tests

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Survival Rates Following Skeletal Metastases—A Twenty-Year Analysis

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Open Journal of Orthopedics 2015年第9期5卷 288-296页

作者： Mohannad b. Ammori Sunil Panchani Jonathan J. Gregory James Wylie Ashok paul Department of Orthopaedic Surgery Royal Gwent Hospital Newport UK Department of Orthopaedic Surgery Manchester Royal Infirmary Manchester UK The Christie Hospital Manchester UK

Introduction: The aims of this study were to estab.ish an estimate of the prognosis and to identify the variab.es predictive of survival following the diagnosis of metastatic b.ne disease. Materials and Methods: Ninety-seven patients diagnosed with skeletal metastases confirmed b. histological examination b.tween 1991 and 2010 were selected. Data were retrospectively collected including age and sex, sites and histology of the primary tumour and skeletal metastases, presence of visceral metastases, pathological fracture, and the treatment received. Results: Ninety-three patients (95.9%) were deceased. The overall rate of survival was 47% at 6 months, 31% at one year and 10% at three years. Multivariate analysis confirmed the grade of malignancy, age and systemic therapy as independent predictors of survival. Discussion and Conclusion: The prognosis of patients with skeletal metastases should b. estimated according to the site and histology of the primary tumour, grade of malignancy and age at the time of presentation.

关键词： Oncology Skeletal Metastases Survival