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Early Results of Urothelial carcinoma Screening in a Risk Population of coke Workers:Urothelial carcinoma among coke Workers

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Biomedical and Environmental Sciences 2010年第4期23卷 300-304页

作者： GIBERTI c GALLO f ScHENONE M GENOVA A Department of Surgery Division of Urology San Paolo Hospital Savona Italy Service of Industrial Medicine Italiana Coke Industry S.r.l

Objective To present the protocol and the early results of a urothelial carcinoma （Uc） screening analysis performed in a risk population of coke workers. Methods Between June 2006 and October 2008, 171 male workers （mean age 43 years）, employed in a Ligurian coke plant （Italiana coke S.r.l） and exposed to polycyclic aromatic hydrocarbons （PAHs） for a median period of 16 years, underwent screening for Uc. Urological evaluation included medical history, physical examination, routine laboratory tests, urine analysis, urinary cytology and ucyt＋ assay. In the event of signs and symptoms suggestive of Uc or positive urinary tests, the workers were also subjected to urinary ultrasonography and cystoscopy with biopsy of any suspicious lesions. Results Regarding the laboratory tests, 19/171 （11%） ucyt＋ samples were considered inadequate and were excluded from the outcomes assessment. Overall, urine analysis, cytology and ucyt＋ were positive in 18/152 （12%） subjects who showed no evidence of Uc at the scheduled check-ups. No significant association was identified between marker positivity and occupational activity. conclusions Our results fail to show an increased risk of Uc among the coke workers evaluated. However, they will need to be confirmed in the future by a larger enrollment and a longer follow-up in order to assess the definitive risk for Uc after exposure to coke.

关键词： Bladder cancer Screening Occupation Risk factor Urinary markers

computer-aided morphometry of liver inflammation in needle biopsies

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World Journal of Gastroenterology 2005年第44期11卷 6995-7000页

作者： N Dioguardi B franceschini c Russo f Grizzi Scientific Direction

AIM: To introduce a computer-aided morphometric method for quantifying the necro-inflammatory phase in liver biopsy specimens using fractal geometry and Delaunay's ***: Two-micrometer thick biopsy sections taken from 78 chronic hepatitis c virus-infected patients were immunohistochemically treated to identify the inflammatory cells. An automatic computer-aided image analysis system was used to define the inflammatory cell network defined on the basis of Delaunay's triangulation,and the inflammatory cells were geometrically classified as forming a cluster (an aggregation of a minimum of three cells) or as being irregularly distributed within the tissue. The phase of inflammatory activity was estimated using Hurst's ***: The proposed automatic method was rapid and objective. It could not only provide rigorous results expressed by scalar numbers, but also allow the state of the whole organ to be represented by Hurst's exponent with an error of no more than 12%.cONcLUSION: The availability of rigorous metrical measures and the reasonable representativeness of the status of the organ as a whole raise the question as to whether the indication for hepatic biopsy should be revised by establishing clear rules concerning the contraindications suggested by its invasiveness and subjective interpretation.

关键词： Biopsy Grading Image analysis fractal geometry Topography Delaunay

Variable retention harvesting in the Douglas-fir region

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Ecological Processes 2020年第1期9卷 83-92页

作者： Jerry f.franklin Daniel c.Donato School of Environmental and forest Science College of the EnvironmentUniversity of WashingtonSeattleWA 98195USA Washington Department of Natural Resources OlympiaWA 98504USA

Variable retention harvesting evolved in the Douglas-fir region of the Pac.fic Northwest gradually in response to increasing dissatisfaction with the ecological consequences of clear-cutting,from the standpoint of wildlife habitat and other important forest *** is a harvesting technique that can provide for retention(continuity)of such structures as large and old live trees,snags,and *** retention is based on the natural model of the biological legacies that are typically left behind following natural disturbances,such as wildfire,wind,and *** retention is also an important technique for fulfilling the first silvicultural principle of ecological forestry,that of providing for continuity in structure,function,and composition between forest *** history and current application of variable retention approaches on forests in western Washington and Oregon states(USA),where many of the fundamental concepts were first developed and applied,is described in this article.

关键词： Biological legacies Ecological forestry Biodiversity conservation Long-term sustainability Washington and Oregon states

Modelling and mapping third dimension in a spatial database

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International Journal of Digital Earth 2011年第6期4卷 505-520页

作者： f.Donera c.Bıyık Department of Geomatics Engineering Gumushane UniversityGumushaneTurkey Department of Geomatics Engineering Karadeniz Technical UniversityTrabzonTurkey

In this paper,an overview of phases for modelling and mapping third dimension of spatial objects in a database is presented based on a selected spatial database management system(DBMS).These phases include(1)defining a spatial reference system for representing three-dimensional(3D)objects with real-world coordinates,(2)geometric modelling of 3D objects in the database,(3)3D spatial indexing for fast accessing/querying the 3D data,3D spatial queries and representation of 3D ***,a case study is performed to assess needs,possibilities and potential limitations of 3D data modelling in the spatial database.

关键词： spatial database geo-data 3D data modelling GIS digital earth

Strain Hardening and Strain Rate Sensitivity Behaviors of Advanced High Strength Steels

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Journal of Iron and Steel Research International 2013年第6期20卷 68-74页

作者： f Ozturk A Polat S Toros R c Picu Department of Mechanical Engineering Nigde University Department of Mechanical Aerospace and Nuclear Engineering Rensselaer Polytechnic InstituteTroy 12180 New York USA

The mechanical properties of commercial dual phase （DP）, transformation induced plasticity （TRIP）, and high strength low alloy （HSLA-340） steel sheets are investigated and compared at various strain rates ranging from 0.001 7to 0.17 s-1 at ambient *** steel outperforms the other two materials , having comparable ductility and twice as large strength relative to DP *** has larger strength and much larger ductility than *** exceuent ductility of TRIP800is due to its high strain hardening capability , which promotes stable plastic *** is observed that the strain hardening rate in TRIP800does not decrease to zero at failure , as common in most materials in which failure is preceded by necking.

关键词： steel advanced high strength steel HSLA DP TRIP hardening

Response of an old landslide to reservoir filling: A case history

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Science china(Technological Sciences) 2005年第Z1期48卷 27-32页

作者： L.G. Tham c.f. Lee Department of civil Engineering University of Hong Kong Hong Kong China

Unfavorable hydrodynamic evolution is considered as the major cause leading to reservoir slope instability and is often modeled by numerical method. However, this simulation is seldom checked by systematic.field instrumentation. Taking the opportunity of filling the Three Gorges Reservoir, a system was established in Xietan landslide to monitor reservoir water level, subground water level, seepage pressure, rainfall and deformation, etc. The monitored data during reservoir filling shows that: (1) The water level rise in the bank lags behind the reservoir filling and the lag time depends on the bank permeability; (2) rainfall-induced subground water rise and its lag time is closely correlated to hourly rainfall, indicating that it is not feasible or sufficient to use daily rainfall for analysis; (3) the effect of inverse seepage during reservoir filling on stability is ephemeral and reservoir filling is the major cause leading to bank instability.

关键词： reservoir filling, old landslide, monitoring system, water level, deformation.

Modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies

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Research in Astronomy and Astrophysics 2011年第12期11卷 1429-1448页

作者： James Q.feng c.f.Gallo Superconix Inc 2440 Lisbon AvenueLake ElmoMN 55042USA

We present an efficient, robust computational method for modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies. With appropriate mathematical treatments, the apparent numerical difficulties associated with singularities in computing elliptic integrals are completely removed. Using a boundary element discretization procedure, the governing equations are transformed into a linear algebra matrix equation that can be solved by straightforward Gauss elimination in one step without further iterations. The numerical code implemented according to our algorithm can accurately determine the surface mass density distribution in a disk galaxy from a measured rotation curve （or vice versa）. for a disk galaxy with a typical flat rotation curve, our modeling results show that the surface mass density monotonically decreases from the galactic center toward the periphery, according to Newtonian dynamics. In a large portion of the galaxy, the surface mass density follows an approximately exponential law of decay with respect to the galactic radial coordinate. Yet the radial scale length for the surface mass density seems to be generally larger than that of the measured brightness distribution, suggesting an increasing mass-tolight ratio with the radial distance in a disk galaxy. In a nondimensionalized form, our mathematical system contains a dimensionless parameter which we call the ＂galactic rotation number＂ that represents the gross ratio of centrifugal force and gravitational force. The value of this galactic rotation number is determined as part of the numerial solution. Through a systematic computational analysis, we have illustrated that the galactic rotation number remains within 4-10% of 1.70 for a wide variety of rotation curves. This implies that the total mass in a disk galaxy is proportional to V02 Rg, with V0 denoting the characteristic rotation velocity （such as the ＂flat＂ value in a typical ro- tation curve） and Rg the radius of the galacti

关键词： galaxy: disk -- galaxies: general -- galaxies: kinematics and dynamics -- galaxies: structure -- methods: numerical and analytical

DYNAMIc cOMPAcTION Of PURE cOPPER POWDER USING PULSED MAGNETIc.fORcE

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 277-283页

作者： H.P. Yu c.f. Li National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin 150001 China

The compaction of pure cu powder was carried out through a series of experiments using dynamic magnetic pulse compaction, and the effects of process parameters, such as discharge energy and compacting direction, on the homogeneity and the compaction density of compacted specimens were presented and discussed. The results indicated that the compaction density of specimens increased with the augment of discharge voltage and time. During unidirectional compaction, there was a density gradient along the loading direction in the compacted specimen, and the minimum compaction density was localized to the center of the bottom of the specimen. The larger the aspect ratio of a powder body, the higher the compaction density of the compacted specimen. And high conductivity drivers were beneficial to the increase of the compaction density. The iterative and the double direction compaction were efficient means to manufacture the homogeneous and high-density powder parts.

关键词： magnetic pulse compaction copper powder compaction density electromagnetic.forming

A RANS-Vof Numerical Model to Analyze the Output Power of An OWc-WEc Equipped with Wells and Impulse Turbines in A Hypothetical Sea-State

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china Ocean Engineering 2020年第6期34卷 760-771页

作者： Paulo R.f.Teixeira Rafael A.A.c.Gonçalves Eric Didier Engineering School Universidade Federal do Rio Grande-FURGRio GrandeRS 96203-900Brazil Harbours and Maritime Structures Division Hydraulics and Environment DepartmentLaboratório Nacional de Engenharia Civil-LNECLisbon 1700-066Portugal

Wave energy is a renewable source with significant amount in relation to the global demand. A good concept of a device applied to extract this type of energy is the onshore oscillating water column wave energy converter(OWc-WEc). This study shows a numerical analysis of the diameter determination of two types of turbines, Wells and Impulse, installed in an onshore OWc device subjected to a hypothetical sea state. commercial software fLUENT?,which is based on RANS-Vof(Reynolds-Averaged Navier-Stokes equations and Volume of fluid technique), is employed. A methodology that imposes air pressure on the chamber, considering the air compressibility effect, is used. The mathematical domain consists of a 10 m deep flume with a 10 m long and 10 m wide OWc chamber at its end(geometry is similar to that of the Pico's plant installed in Azores islands, Portugal). On the top of the chamber, a turbine works with air exhalation and inhalation induced by the water free surface which oscillates due to the incident wave. The hypothetical sea state, represented by a group of regular waves with periods from 6 to 12 s and heights from 1.00 to 2.00 m(each wave with an occurrence frequency), is considered to show the potential of the presented methodology. Maximum efficiency(relation between the average output and incident wave powers) of46% was obtained by using a Wells turbine with the diameter of 2.25 m, whereas the efficiency was 44% by an Impulse turbine with the diameter of 1.70 m.

关键词： wave energy oscillating water column Wells turbine Impulse turbine RANS-Vof compressible air