Osteoblasts infill irregular pores under curvature and porosity controls: A hypothesis-testing analysis of cell behaviours

The geometric control of bone tissue growth plays a significant role in bone remodelling, age-related bone loss, and tissue engineering. However, how exactly geometry influences the behaviour of bone-forming cells remains elusive. Geometry modulates cell populations collectively through the evolving space available to the cells, but it may also modulate the individual behaviours of cells. To factor out the collective influence of geometry and gain access to the geometric regulation of individual cell behaviours, we develop a mathematical model of the infilling of cortical bone pores and use it with available experimental data on cortical infilling rates. Testing different possible modes of geometric controls of individual cell behaviours consistent with the experimental data, we find that efficient smoothing of irregular pores only occurs when cell secretory rate is controlled by porosity rather than curvature. This porosity control suggests the convergence of a large scale of intercellular signalling to single bone-forming cells, consistent with that provided by the osteocyte network in response to mechanical stimulus. After validating the mathematical model with the histological record of a real cortical pore infilling, we explore the infilling of a population of randomly generated initial pore shapes. We find that amongst all the geometric regulations considered, the collective influence of curvature on cell crowding is a dominant factor for how fast cortical bone pores infill, and we suggest that the irregularity of cement lines thereby explains some of the variability in double labelling data as well as the overall speed of osteon infilling.Comment: 14 pages, 11 figures, Appendi

Coupled Ostrovsky equations for internal waves in a shear flow

In the context of fluid flows, the coupled Ostrovsky equations arise when two distinct linear long wave modes have nearly coincident phase speeds in the presence of background rotation. In this paper, nonlinear waves in a stratified fluid in the presence of shear flow are investigated both analytically, using techniques from asymptotic perturbation theory, and through numerical simulations. The dispersion relation of the system, based on a three-layer model of a stratified shear flow, reveals various dynamical behaviours, including the existence of unsteady and steady envelope wave packets.Comment: 47 pages, 39 figures, accepted to Physics of Fluid

Antimicrobial activities of marine fungi from Malaysia

Copyright 2011 Elsevier B.V., All rights reserved.Peer reviewedPublisher PD

High-performance computing and communication models for solving the complex interdisciplinary problems on DPCS

The paper presents some advanced high performance (HPC) and parallel computing (PC) methodologies for solving a large space complex problem involving the integrated difference research areas. About eight interdisciplinary problems will be accurately solved on multiple computers communicating over the local area network. The mathematical modeling and a large sparse simulation of the interdisciplinary effort involve the area of science, engineering, biomedical, nanotechnology, software engineering, agriculture, image processing and urban planning. The specific methodologies of PC software under consideration include PVM, MPI, LUNA, MDC, OpenMP, CUDA and LINDA integrated with COMSOL and C++/C. There are different communication models of parallel programming, thus some definitions of parallel processing, distributed processing and memory types are explained for understanding the main contribution of this paper. The matching between the methodology of PC and the large sparse application depends on the domain of solution, the dimension of the targeted area, computational and communication pattern, the architecture of distributed parallel computing systems (DPCS), the structure of computational complexity and communication cost. The originality of this paper lies in obtaining the complex numerical model dealing with a large scale partial differential equation (PDE), discretization of finite difference (FDM) or finite element (FEM) methods, numerical simulation, high-performance simulation and performance measurement. The simulation of PDE will perform by sequential and parallel algorithms to visualize the complex model in high-resolution quality. In the context of a mathematical model, various independent and dependent parameters present the complex and real phenomena of the interdisciplinary application. As a model executes, these parameters can be manipulated and changed. As an impact, some chemical or mechanical properties can be predicted based on the observation of parameter changes. The methodologies of parallel programs build on the client-server model, slave-master model and fragmented model. HPC of the communication model for solving the interdisciplinary problems above will be analyzed using a flow of the algorithm, numerical analysis and the comparison of parallel performance evaluations. In conclusion, the integration of HPC, communication model, PC software, performance and numerical analysis happens to be an important approach to fulfill the matching requirement and optimize the solution of complex interdisciplinary problems

Perilaku Dan Musuh Alami Kupu Endemik Sulawesi Papilio Blumei: Acuan Dalam Konservasi

Papilio blumei is an endemic butterfly of Sulawesi and especially in Bantimurung Bulusaraung National Park. This research was to observed of the behaviour and natural enemies of P. blumei in Bantimurung Bulusaraung National Park. The behaviour of the insect were mating, foraging, competiting, ovipositing and mud-puddling. Life table was used for analysis of mortality factors, therefore the number of mortality was analyzed by key-factors formulation. The result indicated that mating strategies is patrolling. Foraging activity of the sixth instar was the highest compared to the other instars and the lowest one activity of the prapupa stadium of P. blumei. Nectar host plants for the imago of butterfly were Sarcosephalum latifolius and Eugenia sp. There was Scudderia sp. as an interspesific competitor for larval P. blumei. The intraspesific competitor of the imago stage was male of P. blumei. Female P. blumei laid eggs on abaxial leaf E.hupehensis and the eggs hatched after six days. The larva of P. blumei has a overheating behaviour and the adults has a mud puddling. The natural enemies of P.blumei is Trichogramma sp., with k value = 0.381, Pteromalus sp., with k value = 0.125 and Formica sp., with k value = 0.096

A conducting domain surface boundary applied to hybrid FEM-FDTD Electromagnetic Models

A modified boundary surface between the two domains in the hybrid FEM-FDTD technique is presented. This permits a heterogeneous surface to be imposed, allowing selected parts to be represented as being conducting or non-conducting. This enables a reduced surface size to be used in cases where an antenna is above a conducting plane, as well as facilitating a range of other practical scenarios. Examples presented show stable results and good agreement with published data

Rebuilding a Framework for Learning: Rethinking Structural Design Instruction in an Architectural Curriculum

Architectural design relies upon structural design principles to help gracefully resist the stresses of building elements that enclose spaces. This discipline and expertise of integration typically takes years to develop but unfortunately, instead of teaching these skills side-by-side with coordinated expectations for escalating levels of expertise, representation, and analysis, these courses have frequently been separated from each other in architectural curricula. The oppositional pedagogical methodologies and differential expectations for development that occur as a result of this have adverse consequences for student learning and practical preparedness. This paper, intended for a national target audience of university faculty and practitioners, will outline a series of major curricular changes made to Iowa State University’s structural design course for architecture students which was explicitly reconfigured to address these concerns. Three specific lab assignments will be presented—one from the beginning, middle, and end of the new structural modules—to show how this new sequence has expanded and coordinated the range of curricular considerations within the structural coursework through the use of interactive, design-based learning activities and elevated expectations for course content. The paper will describe the critical aspects of the new curricular format and the corresponding innovations in learning activities in order to demonstrate how these three labs serve as benchmarks of demonstrated learning objectives in the sequence. Examples of student work will be shown, and an assessment of the efficacy of the assignments will be presented including reflections upon lessons learned and suggestions for future improvements

Contingent Valuation Method: Valuing Cultural Heritage

Cultural heritage is not easy to be valued in a market because it is a very unique product which gives a community (ies), nation(s) an identity and a sense of belonging. Debate on the valuation of cultural heritage surrounds despite growing attention by economists and policy makers. The attention on the estimation of economic values for cultural goods and services has been great by economics throughout the past two decades (Choi, et al., 2009; Kaminski, McLoughlin, & Sodagar, 2007; Navrud & Ready, 2002, Noonan, 2003; Venkatachalam, 2004). The two stated preference methods which are commonly used in valuing non-use goods; i.e. contingent valuation method and choice modelling. Each of these two valuation method has its own strengths and weaknesses and may even complement each other depending on the parameters of the study. However, according to Kaminski et al., 2007; Noonan, 2003, the usage of choice modelling to estimate cultural values has been limited due to the growing usage of contingent valuation. Therefore, this paper will discuss contingent valuation method in valuing amenities and aim to contribute the knowledge on contingent valuation method for nonmarket goods. (Abstract by author

Synthesis and Theoretical Study of 4-(2-methyl-4-oxoquinazoline-3(4H)-yl) Benzoic acid with Some Transition Metal Ions

New complexes of the type [ML2(H2O)2] ,[FeL2(H2O)Cl] and [VOL2] were M=Co(II),Ni(II) and Cu(II) ,L=4-(2-methyl-4-oxoquinazoline-3(4H)-yl) benzoic acid were synthesized and characterized by element analysis, magnetic susceptibility ,molar conductance ,FT-IR and UV-visible. The studies indicate that the L acts as doubly monodentate bridge for metal ions and form mononuclear complexes. The complexes are found to be octahedral except V(IV) complex is square pyrimde shape . The structural geometries of compounds were also suggested in gas phase by theoretical treatments, using Hyper chem-6 program for the molecular mechanics and semi-empirical calculations, addition heat of formation(?Hf ?) and binding energy (?Eb)for the free ligands and it’s metal complexes were calculated by using PM3 method .PM3 was used to evaluate the vibration spectra of ligand and compare the theoretically calculated wave numbers with experimental values ,the theoretically obtained frequencies agreed calculation helped to assign unambiguously the most diagnostic bands

Numerical analysis of spray-dic modeling for fruit concentration drying process into powder based on computational fluid dynamic

The drying process is most popular preservation methods. It is important in producing the powder and natural dye by concentration fruit drying. Spray-DIC is one of the concentration techniques for drying process using the nozzle flow application in computational fluid dynamic. The mathematical modeling for drying process in this paper includes mass conservation and energy conservation of fruit concentration based on partial differential equation. The discretization of mathematical model will use the finite difference method with the initial and boundary conditions of nozzle flow application. The mathematical modeling computes numerical in sequential algorithm. Jacobi and Gauss-Seidel scheme will use to solve the linear system of mathematical modeling. The execution time, no of iteration, accuracy, root mean square error and maximum error are measured for investigating the numerical analysis. The results show the Gauss Seidel method is the alternative method compared to Jacobi method for solving the Spray-DIC modeling