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The tectonics and mineral systems of Proterozoic Western Australia:Relationships with supercontinents and global secular change

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Geoscience Frontiers 2018年第2期9卷 295-316页

作者： A.R.A.Aitken S.A.Occhipinti m.D.Lindsay A.Joly H.m.Howard S.P.Johnson J.A.Hollis C.V.Spaggiari I.m.Tyler T.C.mcCuaig m.C.Dentith Centre for Exploration Targeting The University of Western AustraliaPerthWestern AustraliaAustralia The Geological Survey of Western Australia Department of Mines and PetroleumPerthWestern AustraliaAustralia BHP Billiton 125 St Georges TerracePerthAustralia ARC Centre of Excellence for Core to Crust Fluid Systems Centre for Exploration TargetingSchool of Earth SciencesThe University of Western AustraliaAustralia Resource Potentials PerthAustralia Department of Geology The Ministry of Mineral ResourcesGreenland GovernmentGreenland

The cratonisation of Western Australia during the Proterozoic overlapped with several key events in the evolution of Earth. These include global oxidation events and glaciations, as well as the assembly,accretionary growth, and breakup of the supercontinents Columbia and Rodinia, culminating in the assembly of Gondwana. Globally, Proterozoic mineral systems evolved in response to the coupled evolution of the atmosphere, hydrosphere, biosphere and lithosphere. Consequently, mineral deposits form preferentially in certain times, but they also require a favourable tectonic setting. For Western Australia a distinct plate-margin mineralisation trend is associated with Columbia, whereas an intraplate mineralisation trend is associated with Rodinia and Gondwana, each with associated deposit types. We compare the current Proterozoic record of ore deposits in Western Australia to the estimated likelihood of oredeposit formation. Overall likelihood is estimated with a simple matrix-based approach that considers two components: The "global secular likelihood" and the "tectonic setting likelihood". This comparative study shows that at least for the studied ore-deposit types, deposits within Western Australia developed at times, and in tectonic settings compatible with global databases. Nevertheless, several deposit types are either absent or poorly-represented relative to the overall likelihood models. Insufficient exploration may partly explain this, but a genuine lack of deposits is also suggested for some deposit types. This may relate either to systemic inadequacies that inhibited ore-deposit formation, or to poor preservation. The systematic understanding on the record of Western Australia helps to understand mineralisation processes within Western Australia and its past connections in Columbia, Rodinia and Gondwana and aids to identify regions of high exploration potential.

关键词： mineral systems Tectonics Australia

Comparison of Ground Water Bacterial Cell Sizes from the Agricultural, Domestic and Industrial Areas of mysore District, Karnataka State, India

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应用与环境生物学报 2008年第4期14卷 503-509页

作者： Wadie Ahmed mokbel Sadanand m Yamakanamardi Aquatic microbial Ecology Research Laboratory Department of Studies in Zoology University of Mysore Manasagangotri Mysore-570006 Karnataka State India

A two-year study on temporal variations in the ground water heterotrophic bacterial cell sizes of free living bacteria (FLB) and particle bound bacteria (PBB) from the agricultural, domestic and industrial areas was carried out from February 2005 to January 2007. The overall mean cell length of FLB and PBB was similar in all the ground water studied. However, the season wise grouped data revealed significant seasonal changes in cell length of FLB and PBB, as smaller bacteria were noticed during rainy season in the ground water in agricultural area in both the years, and only in the second year of study in domestic and industrial areas. Generally, it was noticed that there were summer maximum and rainy minimum values of the cell length of PBB in the ground water in agricultural, domestic and industrial areas in the second year of study. The Pearson's correlations showed the presence of 8 (in agricultural area), 5 (in domestic) and 3 (in industrial) significant correlations with environmental (Physico-chemical) parameters, respectively. The regression analysis revealed that as much as 12% of variation in the mean length of FLB was due to NO3 (+) in agricultural area and 9% due to total solids (+) in domestic area. However, the 8 % variation in bacterial cell size of FLB was due to mg (+) in industrial area. Whereas, 13 % variation in mean length of PBB was due to SO4 (+) in agricultural area and 10% due to total anions of strong acid (TASA) (+) in domestic area. Furthermore, 10 % of variation was due to PO4 (+) in industrial area. Thus, the statistical analysis revealed that several environmental variables were potentially responsible for some of the temporal variations in aquatic heterotrophic bacterial cell size, suggesting probably the stressed environment in these ecosystems.

关键词：地下水微生物细胞环境保护

Neoadjuvant therapy for pancreas cancer: Past lessons and future therapies

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World Journal of Gastroenterology 2014年第42期20卷 15564-15579页

作者： Jeffrey m Sutton Daniel E Abbott Department of Surgery Division of Surgical Oncology University of Cincinnati Medical Center

Pancreatic adenocarcinoma remains a most deadly malignancy, with an overall 5-year survival of 5%. A subset of patients will be diagnosed with potentially resectable disease, and while complete surgical resection provides the only chance at cure, data from trials of postoperative chemoradiation and/or chemotherapy demonstrate a modest survival advantage over those patients who undergo resection alone. As such, most practitioners believe that completion of multimodality therapy is the optimal treatment. However, the sequence of surgery, chemotherapy and radiation therapy is frequently debated, as patients may benefit from a neoadjuvant approach by initiating chemotherapy and/or chemoradiation prior to resection. Here we review the rationale for neoadjuvant therapy, which includes a higher rate of completion of multimodality therapy, minimizing the risk of unnecessary surgical resection for patients who develop early metastatic disease, improved surgical outcomes and the potential for longer overall survival. However, there are no prospective, randomized studies of the neoadjuvant approach compared to a surgeryfirst strategy; the established and ongoing investigations of neoadjuvant therapy for pancreatic cancer are discussed in detail. Lastly, as the future of therapeutic regimens is likely to entail patient-specific genetic and molecular analyses, and the treatment that is best applied based on those data, a review of clinically relevant biomarkers in pancreatic cancer is also presented.

关键词： Pancreatic cancer Neoadjuvant therapy Chemotherapy Chemoradiation Biomarkers

Analysis of mathematics and Numerical Pattern Formation in Superdiffusive Fractional multicomponent System

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Advances in Applied mathematics and mechanics 2017年第6期9卷 1438-1460页

作者： Kolade m.Owolabi Abdon Atangana Institute for Groundwater Studies Faculty of Natural and Agricultural SciencesUniversity of the Free StateBloemfontein 9300South Africa

In this work,we examine the mathematical analysis and numerical simulation of pattern formation in a subdiffusive multicomponents fractional-reactiondiffusion system that models the spatial interrelationship between two preys and predator *** major result is centered on the analysis of the system for linear *** of the main model reflects that the dynamical system is locally and globally asymptotically *** propose some useful theorems based on the existence and permanence of the species to validate our theoretical *** and efficient methods in space and time are formulated to handle any space fractional reaction-diffusion *** numerically present the complexity of the dynamics that are theoretically *** simulation results in one,two and three dimensions show some amazing scenarios.

关键词： Asymptotically stable coexistence Fourier spectral method numerical simulations predator-prey fractional multi-species system

An Efficient Allocation for Lung Transplantation Using Ant Colony Optimization

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Intelligent Automation & Soft Computing 2023年第2期35卷 1971-1985页

作者： Lina m.K.Al-Ebbini Biomedical Systems and Informatics Engineering Department Hijjawi for Engineering TechnologyYarmouk UniversityIrbid21163Jordan

A relationship between lung transplant success and many features of recipients’/donors has long been ***,modeling a robust model of a potential impact on organ transplant success has proved *** this study,a hybrid feature selection model was developed based on ant colony opti-mization(ACO)and k-nearest neighbor(kNN)classiﬁer to investigate the rela-tionship between the most deﬁning features of recipients/donors and lung transplant success using data from the United Network of Organ Sharing(UNOS).The proposed ACO-kNN approach explores the features space to identify the representative attributes and classify patients’functional status(i.e.,quality of life)after lung *** efﬁcacy of the proposed model was veriﬁed using 3,684 records and 118 input features from the *** developed approach examined the reliability and validity of the lung allocation *** results are promising regarding accuracy prediction to be 91.3%and low computational time,along with better decision capabilities,emphasizing the potential for automatic classiﬁcation of the lung and other organs allocation *** addition,the proposed model recommends a new perspective on how medical experts and clinicians respond to uncertain and challenging lung alloca-tion *** such ACO-kNN model,a medical professional can sum-marize information through the proposed method and make decisions for the upcoming transplants to allocate the donor organ.

关键词： Ant colony optimization(ACO) lung transplantation feature subset selection quality of life(QoL)

Experimental and numerical analyses of pure copper during ECFE process as a novel severe plastic deformation method

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Progress in Natural Science:materials International 2014年第1期24卷 68-74页

作者： m.Ebrahimi F.Djavanroodi Department of mechanical Engineering Iran University of Science and Technology Department of mechanical Engineering Imperial College

In this paper,a new severe plastic deformation method called equal channel forward extrusion(ECFE) process has been proposed and investigated by experimental and numerical approaches on the commercial pure copper billets. The experimental results indicated that the magnitudes of yield strength,ultimate tensile strength and Vickers micro-hardness have been markedly improved from 114 mPa,204 mPa and68 HV as the annealed condition to 269 mPa,285 mPa and 126 HV after the fourth pass of ECFE process,respectively. In addition,scanning electron microscopy observation of the samples showed that the average grain size of the as-received state which is about 22 μm has been reduced to 1.4 μm after the final pass. The numerical investigation suggested that although one pass ECFE process fabricates material with the mean effective strain magnitude of about 1,the level of imposed effective plastic strain gradually diminishes from the circumference to the center of the deformed billet.

关键词： SPD ECFE Tensile test HV SEm Effective strain

Design of hypersonic wavecatcher intake at mach 12 with rectangular-to-elliptical shape transition

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Propulsion and Power Research 2023年第2期12卷 167-179页

作者： Feng-Yuan Zuo Sannu mölder State Key Laboratory for Strength and Vibration of mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China Ryerson University TorontoOntarioCanada

Wavecatcher(inward-turning)intake flows,at design mach 12,are investigated numerically,to display the effect of wall temperature on flow structures and intake *** experiments on shock wave/boundary layer interaction are used to validate the Spalart-Allmaras turbulence model for reproducing the features of hypersonic *** of hypersonic intake flow are performed at different wall temperatures,including isothermal T_(w)Z 300 K,T_(w)Z 1000 K,T_(w)Z 2000 K,and the adiabatic *** shock structures,impinging shock positions,surface streamlines,and the development of internal streamwise vortices are *** mass-averaged performance of intake flow shows that,when the wall temperature changes from T_(w)Z 300 K to adiabatic,the mass capture coefficient decreases from 0.991 to 0.933,the total pressure recovery decreases from 0.200 to 0.083,while exit section mach number decreases from 4.478 to *** results suggest that the osculating design method of wavecatcher intake design can successfully be extended to mach 12,while capturing all airflow at isothermal wall conditions.

关键词： Wavecatcher intake Hypersonic Wall-temperature Aerodynamic Shock structures

A supply chain management in a single-vendor and a singlebuyer integrated inventory model with backorders under imperfect production system

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Journal of Control and Decision 2017年第4期4卷 195-233页

作者： m.Vijayashree R.Uthayakumar The Gandhigram Rural Institute-Deemed University GandhigramIndia

Lead time is an essential factor in any supply chain and inventory management *** stochastic inventory models,lead time is often viewed as a prescribed constant or a random variable that is not subject to *** many practical situations,lead times can be controlled by paying additional *** this viewpoint,notion of the crashing cost into stochastic inventory model,in which lead time can be controlled by additional *** researchers have developed various analytical inventory models we have considered the piecewise linear *** in this proposed model,we derive the mathematical model which is developed by incorporating three types of lead time crashing cost functions(i)exponential function,(ii)polynomial function and(iii)negative exponential *** integrated inventory model is recognized to find the optimal solutions of order quantity,lead time,total cost for buyer,total cost for vendor and the total number of deliveries from the single-vendor to the single-buyer in one production run.A solution process is suggested for solving the proposed model and numerical examples to illustrate the feature of the proposed model,and examined the effect of the key parameters on the optimal solution and managerial implications are *** examples show that this model offers significant improvements over existing models.A computer code using the software matlab is developed to derive the optimal *** main contribution of this paper is developing a mathematical model and an effective solution procedure to find the optimal ***,a graphical representation of the computational algorithm is represented by a flowchart in each model.

关键词： Integrated inventory model supply chain management lead time crashing cost

Thermal stability of biological tissues and their behavior in cold conditions： A mathematical model

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International Journal of Biomathematics 2016年第5期9卷 25-36页

作者： m. A. Khanday Fida Hussaint Department of mathematics University of Kashmir Srinagar 190006 Jammu and Kashmir India

This paper presents an application of finite element method to study the thermoreg- ulatory behavior of three layers of human dermal parts with varying properties. The investigation of temperature distributions in epidermis, dermis and subcutaneous tissue together with Crank-Nicholson scheme at various atmospheric conditions was carried out. The finite element method has been applied to obtain the numerical solution of gov- erning differential equation for one-dimensional unsteady state bioheat equation using suitable values of parameters that affect the heat transfer in human body. The outer skin is assumed to be exposed to cold atmospheric temperatures and the loss of heat due to convection, radiation and evaporation has been taken into consideration. The important parameters like blood mass flow rate, metabolic heat generation rate and thermal conductivity are taken heterogeneous in each layer according to their distinct physiological and biochemical activities. The temperature profiles at various nodal points of the skin and in vivo tissues have been calculated with respect to the severe cold ambient temperatures. The conditions under which hypothermia, non-freezing and freezing injuries develop were illustrated in the graphs.

关键词： Finite element method bioheat equation Cran^Nicholson method