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Mouse models in male fertility research

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Asian Journal of Andrology 2011年第1期13卷 139-151页

作者： Duangporn Jamsai Moira K o＇Bryan Department of Anatomy and Developmental Biology The Australian Research Council （ARC） Centre of Excellence in Biotechnology and Development Monash University Melbourne Victoria 3800 Australia

Limited knowledge of the genetic causes of male infertility has resulted in few treatment and targeted therapeutic options. Although the ideal approach to identify infertility causing mutations is to conduct studies in the human population, this approach has progressed slowly due to the limitations described herein. Given the complexity of male fertility, the entire process cannot be modeled in vitro. As such, animal models, in particular mouse models, provide a valuable alternative for gene identification and experimentation. Since the introduction of molecular biology and recent advances in animal model production, there has been a substantial acceleration in the identification and characterization of genes associated with many diseases, including infertility. Three major types of mouse models are commonly used in biomedical research, including knockoutJknockin/gene-trapped, transgenic and chemical-induced point mutant mice. Using these mouse models, over 400 genes essential for male fertility have been revealed. It has, however, been estimated that thousands of genes are involved in the regulation of the complex process of male fertility, as many such genes remain to be characterized. The current review is by no means a comprehensive list of these mouse models, rather it contains examples of how mouse models have advanced our knowledge of post-natal germ cell development and male fertility regulation.

关键词： infertility male fertility mouse models spermatogenesis

Modelling the smart farm

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Information Processing in Agriculture 2017年第3期4卷 179-187页

作者： Michael J.o’Grady Gregory M.P.o’Hare School of Computer Science University College DublinBelfieldDublin 4Ireland Earth Institute University College DublinBelfieldDublin 4Ireland

Smart farming envisages the harnessing of Information and Communication Technologies as an enabler of more efficient,productive,and profitable farming *** technologies do not suffice on their own;rather they must be judiciously combined to deliver meaningful information in near ***-support tools incorporating models of disparate farming activities,either on their own or in combination with other models,offer one popular approach;exemplars include GPFARM,APSIM,GRAZPLAN amongst many *** models tend to be generic in nature and their adoption by individual farmers is *** technologies offer an opportunity to remedy this situation;farm-specific models that can reflect near real-time events become tractable using such *** on the development,and application of farm-specific models is at a very early *** paper thus presents an overview of models within the farming enterprise;it then reviews the state-of the art in smart technologies that promise to enable a new generation of enterprise-specific models that will underpin future smart farming enterprises.

关键词： Smart agriculture Modelling Sensing Internet of things

Are Ni/and Ni5Fe1/biochar catalysts suitable for synthetic natural gas production?A comparison with g-Al2o3 supported catalysts

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Green Energy & Environment 2023年第3期8卷 744-756页

作者： M.Gonzalez-Castano C.Morales J.C.Navarro de Miguel J.H.Boelte o.Klepel J.I.Flege H.Arellano-García Department of Process and Plant Technology Brandenburg University of Technology(BTU)Cottbus-SenftenbergPlatz der Deutschen 1Cottbus03046Germany Applied Physics and Semiconductor Spectroscopy Brandenburg University of Technology Cottbus-SenftenbergKonrad-Zuse-Strasse 1Cottbus03046Germany Department of Inorganic Chemistry Institute of Materials Science of SevilleConsejo Superior de Investigaciones Cientificas(CSIC)Universidad de Sevilla(US)Avenida Americo Vespucio 49Seville41092Spain Institute of Materials Chemistry Brandenburg University of Technology Cottbus–SenftenbergUniversitatsplatz 1SenftenbergD-01968Germany

Among challenges implicit in the transition to the post-fossil fuel energetic model,the finite amount of resources available for the technological implementation of Co_(2) revalorizing processes arises as a central *** development of fully renewable catalytic systems with easier metal recovery strategies would promote the viability and sustainability of synthetic natural gas production circular *** Ni and NiFe catalysts supported over g-Al_(2)o_(3) oxide as reference materials,this work evaluates the potentiality of Ni and NiFe supported biochar catalysts for Co_(2) *** development of competitive biochar catalysts was found dependent on the creation of basic sites on the catalyst *** lower Turn over Frequencies than Ni/Al catalyst,the absence of basic sites achieved over Ni/C catalyst was related to the depleted catalyst *** NiFe catalysts,analogous Ni_(5)Fe_(1) alloys were constituted over both alumina and biochar *** highest specific activity of the catalyst series,exhibited by the NiFe/C catalyst,was related to the development of surface basic sites along with weaker NiFe-C interactions,which resulted in increased Ni0:Nio surface populations under reaction *** summary,the present work establishes biochar supports as a competitive material to consider within the future low-carbon energetic panorama.

关键词： Biochar catalysts Carbon catalysts Ni catalysts NiFe alloy Bimetallic catalysts Synthetic natural gas Co_(2)methanation

Continuous synthesis of iron oxide （Fe3o4） nanoparticles via thermal decomposition

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Particuology 2016年第3期14卷 47-53页

作者： William Glasgow Ben Fellows Bin Qi Taghi Darroudi Christopher Kitchens Longfei Ye Thomas M. Crawford o. Thompson Mefford Department of Material Science and Engineering Center for Optical Materials Science and Engineering Technologies Clemson University 91 Technology Drive Anderson SC29625 USA Electron Microscopy Laboratory Department of Materials Science and Engineering Clemson University Clemson SC29625 USA Department of Chemical and Biomolecular Engineering Clemson University Clemson SC 29634 USA Department of Physics and Astronomy and Smart State Center for Experimental Nanoscale Physics University of South Carolina 712 Main Street Columbia SC29208 USA

Iron oxide nanoparticles have become of great interest in the medical field for their potential uses in areas such as biomagnetic imaging and hypothermia cancer treatment. Traditionally, particles for these applications are produced through batch-based methodologies. Herein, we demonstrate an alternative continuous flow production method for the synthesis of Fe304 iron oxide nanoparticles. Advantages of continuous flow over the batch method include consistent formation of uniformly spherical particles, thorough mixing of reactants, and capacity for high-volume particle production. In this study, a continu- ous flow reaction mechanism was proposed in which stoichiometric control of reactants had the potential to control final particle size. The project was conducted under the supposition that the iron oleatelligand ratio in the precursor was the greatest size control factor, with a higher ratio resulting in smaller parti- cles. The resulting particles produced by this continuous method were characterized by high-resolution transmission electron microscopy, X-ray diffraction, and magnetometry.

关键词： Continuous flow Iron oxide MagnetiteSynthesis

Towards long-multitemporal change detection using SVI differencing by integrated DWT ISoCLUS: a model for forest temporal dynamics mapping

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International Journal of Digital Earth 2011年第2期4卷 108-132页

作者： Yashon o.oumaa Ryutaro Tateishi Tateishi Laboratory Centre for Environmental Remote Sensing(CEReS)Graduate School of Science and TechnologyChiba University1-33 Yayoi-choInage-kuChiba 263-8522Japan Tateishi Laboratory Centre for Environmental Remote Sensing(CEReS)Chiba University1-33 Yayoi-choInage-kuChiba 263-8522Japan

Characterisation and mapping of land cover/land use within forest areas over long-multitemporal intervals is a complex *** complexity is mainly due to the location and extent of such areas and,as a consequence,to the lack of full continuous cloud-free coverage of those large regions by one single remote sensing *** order to provide improved long-multitemporal forest change detection using Landsat MSS and ETMin part of *** rainforest,and to develop a model for forest change monitoring,wavelet transforms analysis was tested against the ISoCLUS algorithm for the derivation of changes in natural forest cover,as determined using four simple ratio-based Vegetation Indices:Simple Ratio(SR),Normalised Difference Vegetation Index(NDVI),Renormalised Difference Vegetation Index(RDVI)and modified simple ratio(MSR).Based on statistical and empirical accuracy assessments,RDVI presented the optimal index for the case *** overall accuracy statistic of the wavelet derived change/no-change was used to rank the performances of the indices as:RDVI(91.68%),MSR(82.55%),NDVI(79.73%)and SR(65.34%).The integrated discrete wavelet transformISoCLUS(DWTISoCLUS)result was 42.65%higher than the independent ISoCLUS approach in mapping the change/no-change *** methodology suggested in this study presents a cost-effective and practical method to detect land-cover changes in support of decision-making for updating forest databases,and for long-term monitoring of vegetation changes from multisensor *** current research contributes to Digital Earth with regards to geo-data acquisition,data mining and representation of one forest systems.

关键词： digital earth long-multitemporal forest change detection Spectral Vegetation Index Differencing(SVID) ISoCLUS discrete wavelet transform(DWT) integrated DWTISoCLUS

PGE mineralization and melt composition of chromitites in Proterozoic ophiolite complexes of Eastern Sayan,Southern Siberia

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Geoscience Frontiers 2017年第4期8卷 721-731页

作者： o.Kiseleva S.Zhmodik V.S.Sobolev Institute of Geology and Mineralogy SB RAS Novosibirsk State University

The ospino-Kitoi and Kharanur ultrabasic massifs represent the northern and southern ophiolite branches respectively of the Upper onot ophiolitic nappe and they are located in the southeastern part of the Eastern Sayan（SEPES ophiolites）.Podiform chromitites with PGE mineralization occur as lensoid pods within dunites and rarely in harzburgites or serpentinized *** chromitites are classified into type I and type Ⅱ based on their Cr~#.Type I（Cr~# = 59-85） occurs in both northern and southern branches,whereas type Ⅱ（Cr~# = 76-90） occurs only in the northern *** contents range from ∑PGE 88-1189 ppb,Pt/Ir0.04-0.42 to ∑PGE 250-1700 ppb,Pt/Ir 0.03-0.25 for type I chromitites of the northern and southern branches *** type Ⅱ chromitites of the northern branch have ∑PGE contents higher than that of type Ⅰ（468-8617 ppb,Pt/Ir 0.1-0.33）.Parental melt compositions,in equilibrium with podiform chromitites,are in the range of boninitic melts and vary in Al_2o_3,Tio_2 and Feo/Mgo contents from those of type I and type Ⅱ *** melt compositions for type Ⅰ chromitites are（Al_2o_3）_（melt） = 10.6—13.5 wt.%,（Tio_2）_（melt） = 0.01-0.44 wt.%,（Fe/Mg）_（melt） = 0.42-1.81;those for type Ⅱ chromitites are：（Al_2o_3）_（melt） = 7.8-10.5 wt.%,（Tio_2）_（melt） = 0.01-0.25 wt.%,（Fe/Mg）_（melt） = *** are further divided into os-Ir-Ru（Ⅰ） and Pt-Pd（Ⅱ） based on their PGE *** type Ⅰ chromitites show only the os-Ir-Ru pattern whereas type Ⅱ shows both os-Ir-Ru and Pt-Pd *** mineralization in type Ⅰ chromitites is represented by the os-Ir-Ru system,whereas in type Ⅱ it is represented by the os-Ir-Ru-Rh-Pt *** results indicate that chromitites and PGE mineralization in the northern branch formed in a suprasubduction setting from a fluid-rich boninitic melt during active ***,the chromitites and PGE mineralization of the southern branch could have formed in a spreading zone *** peridotites have

关键词： Chromitites PGE mineralization os-Ir-Ru and Pt-Pd patterns ophiolite Eastern Sayan Parental melt

Distribution of heavy metals in soils of Port Harcourt and its environs, Niger Delta, Nigeria

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Chinese Journal of Geochemistry 2011年第4期30卷 415-421页

作者： Minapuye I odigi Lucky o. Ukren Hycienth o. Nwankwoala Department of Geology University of Port Harcourt

Geochemical evaluation of the distribution of heavy metals in soils of Port Harcourt and its environs in the Niger Delta region is presented in respect of anthropogenic factor and index of geoaccumulation. Sixteen (16) soil samples were collected from two horizons (0-10 cm and 100 cm) from the various grids and analyzed. The geo-chemical analyses showed the vertical and horizontal distributions of heavy metals. The results showed the ranges of the metals determined as follows: Pb (6.86-2.49)×10-6, with an average of 4.63×10-6; Cd (0.05-0.00)×10-6, with an average of 0.02×10-6, As (0.01-0.00)×10-6, with an average of 0.00×10-6. Cu (15.36-10.80) ×10-6, with an average of 13.36×10-6, and V (1.36-0.20)×10-6, with an average of 0.94×10-6. Quantification of the degree of pollution was carried out using anthropogenic factor (AF) and index of geoaccumulation (Igeo). The Igeo values of 0.06, 0.02 and 0.00 for Pb, Cd and As, respectively indicate low-level contamination while Zn (1.14) and V (1.40) show me-dium-level contamination. The sources of contamination are attributed to urbanized anthropogenic activities. The majority of the samples analyzed show that the AF values are less than 1 with the exception of vanadium (V) whose AF values range from 2.73 to 13.60×10-6. Vanadium is more enriched than As, Cd, Pb, and Cu. The order of degrees of anthropogenic contamination and index of geoaccumulation in the soil is V >Zn >Pb >Cu >Cd >AS. Metals were retained near the top soil and their concentrations in the deepest horizons were lower and normal for uncontaminated soils. Metal concentrations in the top soil horizons were significantly related to distance from the industrial and hu-man activities.

关键词：三角洲地区重金属尼日尔土壤周围地区尼日利亚地积累指数污染程度

Incipient low-temperature formation of MAX phase in Cr–Al–C films

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Journal of Advanced Ceramics 2018年第2期7卷 143-151页

作者： o.CRISAN A.D.CRISAN National Institute for Materials Physics

Ceramic-metallic MAX phase of chromium aluminium carbide ternary compounds was successfully obtained through deposition by DC sputtering onto Si substrates. A study of the influence of substrate temperature and in-air post-annealing on the film crystallinity and oxidation was undertaken. Scanning electron microscopy （SEM）, wavelength-dispersive X-ray analysis （WDSX）, and X-ray diffraction （XRD） were used for film characterization. It is shown that, at substrate temperature of about 450℃, as-deposited films are amorphous with small nanocrystals. Subsequent annealing in air at 700℃ leads to film crystallization and partial oxidation. WDSX spectroscopy shows that the films oxidise to a depth of around 120 nm, or 5% of total film thickness which amounts at around 2.68 ixm. As a novelty, this demonstrates the possibility of in-air crystallization of Cr2AlC films without significant oxidation. Materials Analysis Using Diffraction （MAUD） software package for a full-profile analysis of the XRD patterns （Rietveld-type） was used to determine that, as a result of annealing, the average crystallite size changes from 7 to 34 nm, while microstrain decreases from 0.79% to 0.24%. A slight tendency of preferential growth along the （10 10） direction has been observed. Such texturing of the microstructure has the potential of inducing beneficial anisotropic fracture behaviour in the coatings, potentially interesting for several industrial applications in load-bearing devices.

关键词： ternary carbides DC sputtering annealing crystallization X-ray diffraction (XRD) wavelength-dispersive X-ray analysis (WDSX)

Influence of strong preformed particle gels on low permeable formations in mature reservoirs

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Petroleum Science 2016年第1期13卷 77-90页

作者： Mahmoud o.Elsharafi Baojun Bai Mc Coy School of Engineering Midwestern State University Department of Geological Sciences & Engineering Missouri University of Science and Technology

In mature reservoirs,the success of preformed particle gel（PPG） treatment rests primarily on the ability of the PPG to reduce and/or plug the high permeable formations,but not damage the low permeable *** test models（filtration test model and pressure test model）were used to determine the effect of PPG on low permeable *** work used a strong preformed particle gel,Daqing（DQ） gel made by a Chinese *** particle gel sizes were ranged from 30 to 120 mesh for this *** are sized in a millimeter or micrometer,which can absorb over a hundred times their weight in *** gel strength was approximately 6500 Pa for a completely swollen PPG with 1 %（weight percentage） NaCl solution（brine）.0.05 %,1 %,and 10 % NaCl solutions were used in *** core permeability was measured before and after PPG *** relationship between cumulative filtration volumes versus filtration times was *** results indicate that DQ gels of a particle size of 30–80 mesh did not damage the cores of a low permeability of 3–25 m *** DQ gels of a smaller particle size ranging from 100 to 120 mesh damaged the core and a cake was formed on the core *** results also indicate that more damage occurred when a high load pressure（400 psi） was applied on the high permeability cores（290–310 m D）.The penetration of the particle gelsinto the low permeable formations can be decreased by the best selection of gel types,particle sizes,and brine concentrations.

关键词： formations reservoirs mature permeability sandstone permeable filtration rock sizes porosity