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Is diabetes a causal agent for colorectal cancer? Pathophysiological and molecular mechanisms

World Journal of gastroenterology 2011年第4期17卷 444-448页

作者： Olga giouleme Michael d diamantidis Marios g Katsaros department of gastroenterology First Propedeutic Department of Internal Medicine Aristotle University of Thessaloniki AHEPA General Hospital

The possible relationship between diabetes mellitus (dM) and colorectal cancer (CRC), concerning pathophysiological and molecular mechanisms is highlighted in this review. The most recent and complete articles and developments in this particular field were thoroughly reviewed. Common risk factors, such as obesity, sedentary lifestyle, and Western diet between dM and CRC, led to the theory that dM might be a causal agent for CRC development. Various studies have connected type 2 dM and CRC, either proximal or distal, in both sexes. Additionally, chronic insulin treatment has been linked with increased colorectal tumor risk among type 2 diabetic patients. Interestingly, elevated hemoglobin A1c has been proven to be an independent predictor of aggressive clinical behavior in CRC patients. These mechanisms include the insulin-like growth factor-hyperinsulinemia theory and the participation of oncogenic intracellular signaling pathways. Furthermore, it has been proposed that Cox-2 inhibitors might have a role in decreasing the incidence of CRC. Finally, the use of statins to reduce the risk for colon cancer in patients with diabetes has remained controversial. diabetic patients over 50 should receive counseling regarding their elevated risk for CRC, and screening colonoscopy should be recommended before initiating insulin therapy. However, there are no current guidelines, and this strategy is not yet applicable to some countries, as the corresponding risk would not allow screening colonoscopy to be adopted. There is strong evidence to indicate that dM is a causal agent for CRC development. This conclusion provides new impetus for re-evaluating CRC screening worldwide.

关键词： diabetes mellitus Colorectal cancer Molecular oncogenic pathways Screening

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Micro-scale Abrasion and Medium Load Multiple Scratch Tests of PVd Coatings

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材料热处理学报 2004年第05B期25卷 1199-1202页

作者： S. Poulat d.g Teer Teer Coatings Ltd Droitwich Worcestershire.U.K.Teer Coatings Ltd Droitwich Worcestershire.U.K.

Micro-scale abrasion testing is widely used to determine the abrasion resistance of thin film coatings; it is a simple technique that can easily be used as part of a quality control procedure, but it has got the disadvantage of not allowing an easy study of the wear mechanisms involved: it is difficult to estimate the load applied on each abrasive particles in the contact between the loaded ball and the specimen. The possibility of using progressive loading scratch testing, a method widely used to assess the adhesion of thin film coatings, to model the abrasive wear of coatings has been studied in the past; the use of multiple scratch tests to study the wear mechanisms corresponding to a single abrasion scratch event has also been studied in the case of bulk materials (ceramics and hard metals). Two coatings, deposited by Closed Field Unbalanced Magnetron Sputter Ion Plating (CFUBMSIP) on ASP23 powder metallurgy steel substrate are chosen to be representative of the use of protective coatings in industry: titanium nitride, which is widely used to prevent tool wear, and TCL graphit-iC?, which is widely used as a wear resistant solid lubricant coating. The two coatings are first characterised by using a standard quality control procedure: their thickness is determined by the cap grinding method, their adhesion by progressive loading scratch. Then micro-scale abrasion tests performed with a slurry at a concentration which promotes grooving wear, and medium load multiple scratch tests performed with diamond indenters are completed; the results of these tests are analysed and compared to determine if there is any correlation between the two sets of results; the multiple scratch tests wear tracks are also observed to determine the wear mechanisms involved.

关键词：微量磨损乱痕硬度试验 PVd 薄膜涂层

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Maternal effects, malaria infections and the badge size of the house sparrow

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Chinese Birds 2015年第4期6卷 215-224页

作者： Philip L.g.Birget Stephen d.Larcombe St Peter’s College University of Oxford Institute of Evolutionary Biology University of Edinburgh Edward grey Institute of Field Ornithology University of Oxford Centre de Recherche de la Tour du Valat Jesus College University of Oxford Institute of Biodiversity Animal Health and Comparative Medicine University of Glasgow

Background: The evolution of sexual signals is not only determined by immediate sexual selection but also by selection arising from the environment and the interaction with developmental *** this study we aimed to investigate how the badge size of male house sparrows(Passer domesticus) is correlated to avian malaria infections as well as to prenatal testosterone exposure,measured as the 2d:4d digit *** rationale behind this study is that the immunosuppressive effect of maternal testosterone deposition combined with the fitness cost imposed by parasites may cause important trade-offs to the development of secondary sexual ***: Assuming that vector abundance is a key variable associated with infection risk by avian malaria,we caught adult male sparrows from eight different populations in the Camargue,France,four of which were located in a vector-controlled area,and the other four in an untreated *** each bird we measured its badge size,digit ratio and took blood to determine its infections *** used PCR to identify the malaria parasite species and strain that caused the ***: Contrary to our expectation,prevalence of disease did not differ across the vector-treatment regions,with around 80 % of birds being infected in both areas,and those infections were caused largely by a single strain,Plasmodium relictum *** infected birds had a badge size not significantly different from uninfected males,there was a condition-dependent association between badge size,infection status and maternal testosterone ***: This study illustrates that the complexity of temporal and ecological dimensions makes the relationships between disease,testosterone-related traits and secondary sexual signals that have been previously reported less general than thought.

关键词： Avian malaria digit ratio Passer domesticus Sexual signals

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Optimal Placement and Sizing of distributed generation Using Metaheuristic Algorithm

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Computer Systems Science & Engineering 2022年第5期41卷 493-509页

作者： d.Nageswari N.Kalaiarasi g.geethamahalakshmi department of Electrical and Electronics Engineering RMK College of Engineering and Technology(RMKCET)Thiruvallur601206India department of Electrical and Electronics Engineering RMK Engineering CollegeGummidipoondi601206India

Power loss and voltage uncertainty are the major issues prevalently faced in the design of distribution *** such issues can be resolved through effective usage of networking reconfiguration that has a combination of distributed generation(dg)units from distribution *** this point of view,optimal placement and sizing of dgs are effective ways to boost the performance of power *** optimum allocation of dgs resolves various problems namely,power loss,voltage profile improvement,enhanced reliability,system stability,and *** research works have been conducted to address the distribution system problems in terms of power loss,energy loss,voltage profile,and voltage stability depending upon optimal dg *** this motivation,the current study designs a Chaotic Artificial Flora Optimization based on Optimal Placement and Sizing of dgs(CAFO-OPSdg)to enhance the voltage profiles and mitigate the power ***,the CAFO algorithm is derived from the incorporation of chaos theory concept into conventional artificial flora optimization AFO algorithm with an aim to enhance the global optimization *** fitness function of CAFO-OPSdg algorithm involves voltage regulation,power loss minimization,and penalty *** consider the actual power system scenario,the penalty factor acts as an important element not only to minimize the total power loss but to increase the voltage profiles as *** experimental validation of the CAFO-OPSdg algorithm was conducted against IEEE 33 Bus system and IEEE 69 Bus *** outcomes were examined under various test *** results of the experiment established that the presented CAFO-OPSdg model is effective in terms of reducing the power loss and voltage deviation and boost-up the voltage profile for the specified system.

关键词： Voltage profile enhancement loss minimization distributed generation optimal dg sizing optimal dg placement metaheuristics

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A Shrinkage Estimator for Combination of Bioassays

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Acta Mathematicae Applicatae Sinica 2007年第3期23卷 467-476页

作者： Jian Xiong d.g. Chen Zhen-hai Yang College of Applied Sciences Beijing University of Technology Beijing 100022 China School of Mathematics and Information Science Guangzhou University Guangzhou 510006 China department of Mathematics and Statistics South Dakota State University Brookings SD 57007 USA

A shrinkage estimator and a maximum likelihood estimator are proposed in this paper for combination of bioassays. The shrinkage estimator is obtained in closed form which incorporates prior information just on the common log relative potency after the homogeneity test for combination of bioassays is accepted. It is a practical improvement over other estimators which require iterative procedure to obtain the estimator for the relative potency. A real data is also used to show the superiorities for the newly-proposed procedures.

关键词： Common log relative potency parallel-line bioassay slope-ratio bioassay prior information,posterior distribution marginal sufficiency

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Sewage Sludge Usage in Cotton Crop: I. Influence on SoilProperties

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Pedosphere 1999年第2期9卷 147-152页

作者： C.d.TSAdILAN d．g．dIMOYIANNIS 等 NationalAgriculturalResearchFoundation InstituteofSoilClassificationandMappingLarissa41335Greece Na

A field experiment with cotton was conducted on a well drained, calcareous, clay loamy Typic Xerochreptto investigate the utility of sewage sludge as a partial substitute for fertilizers and the influence of its application on the basic soil properties and heavy metal concentrations. The experimental design was completelyrandomized blocks with five treatments replicated four times each. Sewage sludge came from the treatmentplant of the municipality of Volos, Central greece, with the following characteristics: organic matter content36.6 %, pH (H2O 1:5) 6.89, CaCO3 53.4 g kg-1 , total N 26.5 g kg--1, total P 33.5 g kg--1 , and total K 968mg kg--1 soil. Heavy metal concentrations were Cd 5.24, Pb 442, Ni 38, Cu 224, Zn 1 812, and Mn 260 mgkg--1 dry weight, respectively. The soil was high in potassium (K) and poor in available phosphorus (P). Theresults showed that sewage sludge application increased cotton yield and K and P concentrations in cottonleaves. Soil pH was reduced in the case of higher sewage sludge rate. Electrical conductivity, organic mattercontent, total N, and available P were significantly increased. Total concentrations of Zn, Pb, and Cu wereslightly increased. dTPA-extractable Zn, Cu and Mn were also significantly increased. Available forms ofall heavy metals, except Cd, were significantly correlated with organic matter content in a positive way andnegatively with soil pH.

关键词： cotton heavy metals sewage sludge soil properties

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Simulations of granular flow along an inclined plane using the Savage-Hutter model

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Particuology 2012年第2期10卷 236-241页

作者： Minglong Fei Qicheng Sun deyu Zhong gordon g.d.Zhou State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

In this work a velocity-dependent friction is introduced into a depth-averaged 5avage-Hutter dynamical model for shallow granular flows. The process of granular material flowing along an inclined plane and then depositing on a horizontal plane is simulated. The surface profiles and evolution of various types of energy are investigated and compared when using the standard Coulomb-type friction versus velocity- dependent friction. Interestingly, there is a small difference between the two different types of friction.

关键词： granular flowsdynamics frictionSavage-Flutter model

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Ellipsometric Spectra and Optical Properties of Anisotropic SrBi2Ta2O9 Films

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Chinese Physics Letters 2004年第2期21卷 266-268页

作者：莫党刘毅 g.d.Hu J.B.Xu StateKeyLaboratoryofOptoelectronicMaterialsandTechnologiesanddepartmentofPhysics ZhongshanUniversityGuangzhou510275 NormalCollege ShenzhenUniversityShenzhen518060 departmentofElectronicEngineeringandMaterialScienceandTechnologyResearchCenter TheChineseUniversityofHongKongHongKong

Ellipsometric spectra of the SrBi2Ta2O9 (SBT) films of (200) and (0010) predominant orientation are measured and analysed in the range of photon energy from 2 to 5eV. The results show that the oriented SBT films appear to be strongly anisotropic. The ellipsometric spectra of the (200)-predominant SBT films are different from those of the (0010)-predominant films. We suggest an analysis model for these oriented films and perform the fitting of the anisotropic ellipsometric spectra. The refractive index and the extinction coefficient of the ordinary ray and the extraordinary ray for these oriented SBT films are obtained. The ordinary refractive index is larger than the extraordinary one.

关键词： Anisotropy

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Wet chemical synthesis of La_(9.83–x)Sr_xSi_6O_(26+δ)(0≤x≤0.50) powders, characterization of intermediate and final products

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Journal of Rare Earths 2015年第3期33卷 320-326页

作者： Kioupis d. Argyridou M. gaki A. Kakali g. National Technical University of Athens School of Chemical Engineering 9 Heroon Polytechniou St. Athens 15773 Greece

In this paper we reported the preparation and extensive characterization of La9.83–x Sr x Si6O26＋δ（0≤x≤0.50） precursors, intermediate and final products. The sintering reactions, the phase formation, the structure as well as the powders＇ morphology were studied by means of thermogravimetric analysis, X-ray diffraction（XRd）, Fourier-transform infrared spectroscopy（FTIR） and scanning electron microscopy（SEM）. Moreover, the effect of stoichiometry on precursor＇s structure and morphology as well as on intermediate and final products was reported. As was concluded pure La9.83Si6O26＋δ, La9.38Sr0.45Si6O26＋δ and La9.33Sr0.50Si6O26＋δ could be prepared after sintering at 1400 °C for 20 h while La9.68Sr0.15Si6O26＋δ and La9.53Sr0.30Si6O26＋δ compounds contained minor traces（〈3.5%） of La2Si2O7 secondary phase. Concerning the synthesis, there have been no previous reports on the preparation of pure La9.83Si6O26＋δ, La9.38Sr0.45Si6O26＋δ and La9.33Sr0.50Si6O26＋δ compounds. The final powders consisted of spherical particles and an increase of Sr content seemed to inhibit sintering phenomena. The existence of interstitial oxygen at intermediate crystallographic positions of apatite structure had great effect on Si O4 sub-structure distortion. The increase of Sr content led to a major reduction of interstitial oxygen quantity and the refutation of silicon tetrahedron distortion.

关键词： lanthanum silicates synthesis modified Pechini method characterization rare earths

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Implementation aspects of a phase-field approach for brittle fracture

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 417-428页

作者： g.d.HUYNH X.,ZHUANg H.NgUYEN-XUAN Institute of Continuum Mechanics Leibniz-Universitat Hannover30167 HannoverGermany Center for Interdisciplinary Research in Technology Ho Chi Minh CityUniversity of Technology (HUTEH)Ho Chi Minh City Vietnam

This paper provides a comprehensive overview of a phase-field model of fracture in solid mechanics setting. We start reviewing the potential energy governing the whole process of fracture including crack initiation, branching or merging. Then, a discretization of system of equation is derived, in which the key aspect is that for the correctness of fracture phenomena, a split into tensile and compressive terms of the strain energy is performed, which allows crack to occur in tension, not in compression. For numerical analysis, standard finite element shape functions are used for both primary fields including displacements and phase field. A staggered scheme which solves the two fields of the problem separately is utilized for solution step and illustrated with a segment of Python code.

关键词： phase-field modeling FEM staggered scheme fracture

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