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‣ Use of Leptospira spp. strains isolated in Brazil in the microscopic agglutination test applied to diagnosis of leptospirosis in cattle herds in eight brazilian states

Sarmento, Anna M. C.; Azevedo, Sergio S.; Morais, Zenaide M.; Souza, Gisele O.; Oliveira, Flavia C. S.; Goncales, Amane P.; Miraglia, Fabiana; Vasconcellos, Silvio A.
Fonte: REVISTA PESQUISA VETERINARIA BRASILEIRA; RIO JANEIRO Publicador: REVISTA PESQUISA VETERINARIA BRASILEIRA; RIO JANEIRO
Tipo: Artigo de Revista Científica
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Sarmento A.M.C., Azevedo S.S., Morais Z.M., Souza G.O., Oliveira F.C.S., Goncales A.P., Miraglia F. & Vasconcellos S.A. 2012. [Use of Leptospira spp. strains isolated in Brazil in the microscopic agglutination test applied to diagnosis of leptospirosis in cattle herds in eight brazilian states.] Emprego de estirpes Leptospira spp. isoladas no Brasil na microtecnica de soroaglutinacao microscopica aplicada ao diagnostico da leptospirose em rebanhos bovinos de oito estados brasileiros. Pesquisa Veterinaria Brasileira 32(7);601-606. Universidade de Sao Paulo, Faculdade de Medicina Veterinaria e Zootecnia, Departamento de Medicina Veterinaria Preventiva e Saude Animal, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508-270, Brazil. E-mail: savasco@usp.br The aim of this study was to investigate the adequacy of the use of autochthonous strains of leptospires isolated in Brazil, added to antigen collection of the microscopic agglutination test (MAT) applied to the diagnosis of bovine leptospirosis. By means of non-probability sampling, 109 farms and 9,820 cattle, females at reproductive age were chosen from 85 municipalities in the states of Goias, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Parana, Rio Grande do Sul, Santa Catarina and Sao Paulo. Among the 9...

‣ Modeling a Growth Instability in Stressed Boron Doped Silicon

Gray, Leonard J.; Kaplan, Ted; Aziz, Michael; Barvosa-Carter, William; Phan, Anh Vu
Fonte: Applied Computational Research Society; Nano science and technology institute Publicador: Applied Computational Research Society; Nano science and technology institute
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The effects of rate-enhancing dopants and externally applied stress on interfacial growth during silicon crystallization are modeled using advanced numerical methods. The boron doped crystalline Si is modeled as an isotropic linear elastic solid, and the amorphous as a viscous fluid with a time dependent viscosity to reflect structural relaxation. The e ffect of the dopant is included through its position dependent effect on the rate of crystallization at the interface. Appropriate coupling conditions across the boundary are defined, and both problems are solved using advanced boundary integral methods. The interface is advanced in time using the level set technique. The simulation results match well with experiments and support the fact that both stress and dopant-gradient e ffects, along with interface orientation e ffects, must be accounted for to explain the observed behavior. These new effects are of general relevance to the growth of all non-hydrostatically stressed solids, and are therefore important in film synthesis, with potentially significant applications in electronic devices and thin film coatings.; Engineering and Applied Sciences

‣ Application of harmonic coordinates to 2D interface problems on regular grids

Binford, Tommy L., Jr.
Fonte: Universidade Rice Publicador: Universidade Rice
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Finite difference and finite element methods exhibit first order convergence when applied to static interface problems where the grid and interface are not aligned. Although modified and unstructured grid methods would address the issue of misalignment for finite elements, application to large models of stratified media, such as those encountered in exploration geophysics, may require not only manual mesh manipulation but also more degrees of freedom than are ultimately necessary to resolve the solution. Instead using fitted or otherwise modified grids, this thesis details an improvement to an existing upscaling method that incorporates fine-scale variations of material properties by composing standard piecewise linear basis functions with a specific type of harmonic map. This technique requires that the problem domain be discretized using two meshes: one fine mesh where the harmonic map is computed to resolve fine-scale structures, and a coarse mesh where the solution to the problem is approximated. The implementation of this method in the literature restricts these composite basis functions to triangular elements in 2D leading to a non-conforming finite element method and suboptimal convergence. However, the support of these basis functions in harmonic coordinates is triangular. I present a mesh-mesh intersection algorithm that exploits this alternative representation to determine the true support of the composite basis functions in terms of the fine mesh. The result is a conforming...

‣ Harmonic Wavelets Procedures and Wiener Path and Integral Methods for Response Determination and Reliability Assessment of Nonlinear Systems/Structures

Kougioumtzoglou, Ioannis A.
Fonte: Universidade Rice Publicador: Universidade Rice
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In this thesis a novel approximate/analytical approach based on the concepts of stochastic averaging and of statistical linearization is developed for the response determination of nonlinear/hysteretic multi-degree-of-freedom (MDOF) systems subject to evolutionary stochastic excitation. The significant advantage of the approach relates to the fact that it is readily applicable for excitations possessing even non-separable evolutionary power spectra (EPS) circumventing ad hoc pre-filtering and pre-processing excitation treatments associated with existing alternative schemes of linearization. Further, the approach can be used, in a rather straightforward manner, in conjunction with recently developed design spectrum based analyses for obtaining peak response estimates without resorting to numerical integration of the nonlinear equations of motion. Furthermore, a novel approximate/analytical Wiener path integral based solution (PIS) is developed and a numerical PIS approach is extended to determine the response and first-passage probability density functions (PDFs) of nonlinear/hysteretic systems subject to evolutionary stochastic excitation. Applications include the versatile Preisach hysteretic model, recently applied in modeling systems equipped with smart material (shape memory alloys) devices used for seismic hazard risk mitigation. The approach is also applied to determine the capsizing probability of a ship...

‣ Novel Exogenous Agents for Improving Articular Cartilage Tissue Engineering

Responte, Donald Joseph
Fonte: Universidade Rice Publicador: Universidade Rice
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This thesis demonstrated the effects of exogenous stimuli on engineered articular cartilage constructs and elucidated mechanisms underlying the responses to these agents. In particular, a series of studies detailed the effects of chondroitinase-ABC (C-ABC), hyaluronic acid (HA), and TGF-β1 on the biochemical and biomechanical properties of self-assembled articular cartilage. Work with C-ABC showed that this catabolic agent can be employed to improve the tensile properties of constructs. When constructs were cultured for 6 weeks, treating with C-ABC at 2 weeks enhanced the tensile stiffness. Furthermore, treating at 2 and 4 weeks synergistically increased tensile properties and allowed compressive stiffness to recover to control levels. Another study showed that combining C-ABC and TGF-β1 synergistically enhanced the biochemical and biomechanical properties of neotissue. Microarray analysis demonstrated that TGF-β1 increased MAPK signaling in self-assembled neocartilage whereas C-ABC had minimal effects on gene expression. SEM analysis showed that C-ABC increased collagen fibril diameter and fibril density, indicating that C-ABC potentially acts via a biophysical mechanism. Constructs treated with C-ABC and TGF-β1 also showed stability and maturation in vivo ...

‣ A coupled finite volume and discontinuous Galerkin method for convection-diffusion problems

Yang, Xin
Fonte: Universidade Rice Publicador: Universidade Rice
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This work formulates and analyzes a new coupled finite volume (FV) and discontinuous Galerkin (DG) method for convection-diffusion problems. DG methods, though costly, have proved to be accurate for solving convection-diffusion problems and capable of handling discontinuous and tensor coefficients. FV methods have proved to be very efficient but they are only of first order accurate and they become ineffective for tensor coefficient problems. The coupled method takes advantage of both the accuracy of DG methods in the regions containing heterogeneous coefficients and the efficiency of FV methods in other regions. Numerical results demonstrate that this coupled method is able to resolve complicated coefficient problems with a decreased computational cost compared to DG methods. This work can be applied to problems such as the transport of contaminant underground, the CO 2 sequestration and the transport of cells in the body.

‣ Sponsored Program Annual Report / Applied Mathematics. Fiscal Year 2002

Fonte: Naval Postgraduate School (U.S.) Publicador: Naval Postgraduate School (U.S.)
Tipo: Relatório
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The Naval Postgraduate School has a strong Sponsored Program that has grown steadily to provide the faculty and staff support that is required to sustain a strong and viable graduate school. In fiscal year 2002, the Naval Postgraduate School had available over $80M in sponsored program funding. This amount included multi-year projects from FY01 and those continuing into FY03. The total expenditures in FY02 exceeded $57M. An overview of the NPS Program is provided below, as well as data for the organizational units involved in sponsored program activities.

‣ Accelerated Discontinuous Galerkin Solvers with the Chebyshev Iterative Method on the Graphics Processing Unit

Tullius, Toni Kathleen
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Thesis; Text Formato: 76 p.; application/pdf
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This work demonstrates implementations of the discontinuous Galerkin (DG) method on graphics processing units (GPU), which deliver improved computational time compared to the conventional central processing unit (CPU). The linear system developed when applying the DG method to an elliptic problem is solved using the GPU. The conjugate gradient (CG) method and the Chebyshev iterative method are the linear system solvers that are compared, to see which is more efficient when computing with the CPU's parallel architecture. When applying both methods, computational times decreased for large problems executed on the GPU compared to CPU; however, CG is the more efficient method compared to the Chebyshev iterative method. In addition, a constant-free upper bound for the DC spectrum applied to the elliptic problem is developed. Few previous works combine the DG method and the GPU. This thesis will provide useful guidelines for the numerical solution of elliptic problems using DG on the GPU.

‣ Viscosity Evaluation of Heavy Oils from NMR Well Logging

Yang, Zheng
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Thesis; Text Formato: 188 p.; application/pdf
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Heavy oil is characterized by its high viscosity, which is a major obstacle to both logging and recovery. Due to the loss of T 2 information shorter than the echo spacing ( TE ), estimation of heavy oil properties from NMR T 2 measurements is usually problematic. In this work, a new method has been developed to overcome the echo spacing restriction of NMR spectrometer during the measurement of heavy oil. A FID measurement supplemented the CPMG in an effort to recover the lost T 2 data. Constrained by the initial magnetization ( M 0 ) estimated from the FID and Curie's law and assuming lognormal distribution for bitumen, the corrected T 2 of bitumen can be obtained. This new method successfully overcomes the TE restriction of the NMR spectrometer and is nearly independent on the TE applied in the measurement. This method was applied in the measurement of systems at elevated temperatures (8 ∼ 90 °C) and some important petrophysical properties of Athabasca bitumen, such as hydrogen index ( HI ), fluid content and viscosity were evaluated by using the corrected T 2 . Well log NMR T 2 measurements of bitumen appear to be significantly longer than the laboratory results. This is likely due to the dissolved gas in bitumen. The T 2 distribution depends on oil viscosity and dissolved gas concentration...

‣ Psychometric properties of the Child Health Assessment Questionnaire (CHAQ) applied to children and adolescents with cerebral palsy

MORALES, Nivea de Macedo Oliveira; FUNAYAMA, Carolina Araujo Rodrigues; RANGEL, Viviane O.; FRONTAROLLI, Ana Claudia; ARAUJO, Renata R. H.; PINTO, Rogerio M. C.; REZENDE, Carlos H. A.; SILVA, Carlos H. M.
Fonte: BIOMED CENTRAL LTD Publicador: BIOMED CENTRAL LTD
Tipo: Artigo de Revista Científica
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Background: Cerebral palsy (CP) patients have motor limitations that can affect functionality and abilities for activities of daily living (ADL). Health related quality of life and health status instruments validated to be applied to these patients do not directly approach the concepts of functionality or ADL. The Child Health Assessment Questionnaire (CHAQ) seems to be a good instrument to approach this dimension, but it was never used for CP patients. The purpose of the study was to verify the psychometric properties of CHAQ applied to children and adolescents with CP. Methods: Parents or guardians of children and adolescents with CP, aged 5 to 18 years, answered the CHAQ. A healthy group of 314 children and adolescents was recruited during the validation of the CHAQ Brazilian-version. Data quality, reliability and validity were studied. The motor function was evaluated by the Gross Motor Function Measure (GMFM). Results: Ninety-six parents/guardians answered the questionnaire. The age of the patients ranged from 5 to 17.9 years (average: 9.3). The rate of missing data was low(< 9.3%). The floor effect was observed in two domains, being higher only in the visual analogue scales (<= 35.5%). The ceiling effect was significant in all domains and particularly high in patients with quadriplegia (81.8 to 90.9%) and extrapyramidal (45.4 to 91.0%). The Cronbach alpha coefficient ranged from 0.85 to 0.95. The validity was appropriate: for the discriminant validity the correlation of the disability index with the visual analogue scales was not significant; for the convergent validity CHAQ disability index had a strong correlation with the GMFM (0.77); for the divergent validity there was no correlation between GMFM and the pain and overall evaluation scales; for the criterion validity GMFM as well as CHAQ detected differences in the scores among the clinical type of CP (p < 0.01); for the construct validity...

‣ An exploratory analysis of large health cohort study using Bayesian networks

Shen, Delin
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 98 p.
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Large health cohort studies are among the most effective ways in studying the causes, treatments and outcomes of diseases by systematically collecting a wide range of data over long periods. The wealth of data in such studies may yield important results in addition to the already numerous findings, especially when subjected to newer analytical methods. Bayesian Networks (BN) provide a relatively new method of representing uncertain relationships among variables, using the tools of probability and graph theory, and have been widely used in analyzing dependencies and the interplay between variables. We used BN to perform an exploratory analysis on a rich collection of data from one large health cohort study, the Nurses' Health Study (NHS), with the focus on breast cancer. We explored the data from the NHS using BN to look for breast cancer risk factors, including a group of Single Nucleotide Polymorphisms (SNP). We found no association between the SNPs and breast cancer, but found a dependency between clomid and breast cancer. We evaluated clomid as a potential riskfactor after matching on age and number of children. Our results showed for clomid an increased risk of estrogen receptor positive breast cancer (odds ratio 1.52, 95% CI 1.11-2.09) and a decreased risk of estrogen receptor negative breast cancer (odds ratio 0.46...

‣ Neuromuscular modularity and behavioral correlates of motor control

Overduin, Simon Alexander
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 276 p.
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I studied organizational principles that may subserve the control and learning of forelimb movements. Among these principles, I focused on muscular coordination patterns, motor cortical excitability, and sensorimotor interactions. I found that muscle activity in grasping and reaching behaviors could be reconstructed by linear combinations of a small number of time-varying muscle synergies, each fit with coefficients unique to the behavior. However, the generalization of these synergies between behavioral conditions was limited, in part by the sensitivity of the extraction algorithm to stereotyped muscular relations within contrasted conditions. In reaching studies designed to assist or resist different movement directions, I found a gradual change in the structure, as well as recruitment, of synergies. When a perturbation was targeted to the activity within a single muscle, I found a transient, relative suppression of this muscle in response to descending motor commands. In other motor cortical microstimulation experiments, I confirmed that long-train microstimulation is able to evoke complex, convergent movements. Even during highly-trained reaching movements, I found that there was relatively little invariance of the muscular patterns in relation to kinematic variables coding for the hand's displacement and velocity.; (cont.) In two studies examining the kinematic consequences of modulating cortical excitability...

‣ The bioenergetics of walking and running in space suits

Carr, Christopher E. (Christopher Edward), 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 195 p.; 10695798 bytes; 10707819 bytes; application/pdf; application/pdf
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Space-suited activity is critical for human spaceflight, and is synonymous with human planetary exploration. Space suits impose kinematic and kinetic boundary conditions that affect movement and locomotion, and in doing so modify the metabolic cost of physical activity. Metabolic requirements, found to be significantly elevated in space-suited activity, are a major driver of the allowable duration and intensity of extravehicular activity. To investigate how space suited locomotion impacts the energetics of walking and running, I developed a framework for analyzing energetics data, derived from basic thermodynamics, that clearly differentiates between muscle efficiency and energy recovery. The framework, when applied to unsuited locomotion, revealed that the human run-walk transition in Earth gravity occurs when energy recovery for walking and running are approximately equal. The dependence of muscle efficiency on gravity -during locomotion and under a particular set of assumptions- was derived as part of the framework. Next, I collected and transformed data from prior studies of suited and unsuited locomotion into a common format, and performed regression analysis. This analysis revealed that in reduced gravity environments, running in space suits is likely to be more efficient...

‣ Effects of tool positions on borehole acoustic measurements : a stretched grid finite difference approach

Huang, Xiaojun, 1970-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 286 leaves; 19547723 bytes; 19547477 bytes; application/pdf; application/pdf
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This dissertation made three contributions to numerical simulation and borehole acoustic logging. The first one is a novel finite difference time domain algorithm that features non- uniform grid, wavelet-based difference operator and anisotropic perfectly matched layer. This algorithm reduces numerical reflections and wave distortions introduced by grid change to a minimum by sampling the physical space with gradually varying mesh. By coordinate stretching, the algorithm discretizes the physical space with variable grid, while solving the wave equation on a uniform mesh. That approach helps retain the advantages pertaining to uniform mesh. Further improvement in efficiency is achieved without losing accuracy by the development of a wavelet-based difference operator. By using a family of compactly supported wavelet function, the wavelet- based finite difference time domain algorithm allows less grid point per wavelength. Coordinate stretching is also employed in deriving an anisotropic perfectly matched layer, superior to currently available perfectly matched layer formulation which re quires field splitting, a process that results in more computer memory requirement for the storage of extra variables. Validations of the algorithm include comparison with analytical solutions...

‣ Combinatorial analysis of sequential firing patterns across multiple neurons decoding memory of sequential spatial experience in rat hippocampus

Lee, Albert K. (Albert Kimin), 1972-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 104 p.; 4541549 bytes; 4541356 bytes; application/pdf; application/pdf
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There is broad agreement that the hippocampus is crucially involved in the formation of richly-detailed, long term memories of events in humans. A key aspect of such memories is the temporal order and spatial context of the events experienced. Evidence from a wide variety of behavioral and electrophysiological experiments indicates that the rodent hippocampal spatial memory system is a model system for studying this type of memory in humans. Here, we develop a new combinatorial method for analyzing sequential firing patterns involving an arbitrary number of neurons based on relative time order. We then apply this method to decode memories of sequential spatial experience in the rat hippocampus during slow wave sleep. Specificaly, rats are trained to repeatedly run through a sequence of spatial receptive fields ("place fields") of hippocampal CA1 "place cells" in a fixed temporal order. The spiking activity of many such individual cells is recorded before (PRE), during (RUN), and after (POST) this experience. By treating each place field traversed as an individual event, the rat's experience in RUN can be represeted by the resulting sequence of place fields traversed, and therefore by the activity of the corresponding place cells. Then to characterize the extent to which the sequential nature of the RUN experience has been encoded into memory...

‣ Growing up virtual : the computational lessons of development

Lyons, Derek Eugen
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 205 p.; 7564590 bytes; 7589626 bytes; application/pdf; application/pdf
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Cognitive development is one of nature's most important mechanisms for creating robustly adaptive intelligent creatures. From felids to oscines, developing animals are capable of learning in adverse environments with a reliability that often outpaces the current state-of-the-art in artificial intelligence (AI) The purpose of this thesis, therefore, is to examine how insights from cognitive development might be applied to the design of AI architectures. Starting with a targeted review of the ethological literature, I identify the key computational lessons of development, the fundamental conceptual insights that suggest intriguing new strategies for behavioral organization. These insights are then employed in the design of a developmental behavior architecture in which a hierarchical motivation-based behavior system is coupled to a distributed set of domain-specific learning tools. The architecture is deployed in a synthetic character (Hektor the mouse) whose challenge is to learn to play a competitive card matching game successfully against a human user. Evaluation of Hektor's performance on this task, at both qualitative and quantitative levels of description, reveal that the developmental architecture is capable of surmounting complex learning objectives in a novel and efficient manner. I conclude that the architecture presented here represents a valuable starting point for further consideration of developmental design principles.; by Derek Eugen Lyons.; Thesis (S.M.)--Massachusetts Institute of Technology...

‣ Human-machine collaboration for rapid speech transcription

Roy, Brandon C. (Brandon Cain)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 127 p.
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Inexpensive storage and sensor technologies are yielding a new generation of massive multimedia datasets. The exponential growth in storage and processing power makes it possible to collect more data than ever before, yet without appropriate content annotation for search and analysis such corpora are of little use. While advances in data mining and machine learning have helped to automate some types of analysis, the need for human annotation still exists and remains expensive. The Human Speechome Project is a heavily data-driven longitudinal study of language acquisition. More than 100,000 hours of audio and video recordings have been collected over a two year period to trace one child's language development at home. A critical first step in analyzing this corpus is to obtain high quality transcripts of all speech heard and produced by the child. Unfortunately, automatic speech transcription has proven to be inadequate for these recordings, and manual transcription with existing tools is extremely labor intensive and therefore expensive. A new human-machine collaborative system for rapid speech transcription has been developed which leverages both the quality of human transcription and the speed of automatic speech processing. Machine algorithms sift through the massive dataset to find and segment speech. The results of automatic analysis are handed off to humans for transcription using newly designed tools with an optimized user interface. The automatic algorithms are tuned to optimize human performance...

‣ Medical ethics as practiced by students, nurses and faculty members in Shiraz University of Medical Sciences

BAZRAFCAN, LEILA; NABEIEI, PARISA; SHOKRPOUR, NASRIN; MOADAB, NEDA
Fonte: Shiraz University of Medical Sciences Publicador: Shiraz University of Medical Sciences
Tipo: Artigo de Revista Científica
Publicado em /01/2015 Português
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Introduction: Assuming any social role has obligations and fulfilling the related responsibilities has ethical aspects that must be addressed carefully. Each role requires extensive training, which usually takes place in university institutions. Ethics is applied in at least three academic areas, including: a) in education of students' personal growth, b) in patient care, and c) in university communion in population-based health care. Given the importance of this issue in the moral domain, this study examines the correlation among the students, nurses and teacher's opinions regarding principles of medical ethics at Shiraz University of Medical Sciences.

‣ Role of the secretome in manganese and carbon oxidation by filamentous ascomycete fungi

Zeiner, Carolyn Alexandra
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation; text Formato: application/pdf
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Fungi are the primary decomposers of recalcitrant plant and animal material in terrestrial environments, thereby serving as important drivers of global carbon cycling and climate dynamics and as mediators in renewable energy production. Degradation of organic litter is achieved through secretion of a large and diverse suite of extracellular enzymes and reactive metabolites, collectively referred to as the secretome. This thesis explores the secretomes of four filamentous Ascomycete fungi that were recently isolated from field sites and have the ability to oxidize manganese (Mn)(II) to Mn(III/IV) oxides: Alternaria alternata SRc1lrK2f, Stagonospora sp. SRC1lsM3a, Pyrenochaeta sp. DS3sAY3a, and Paraconiothyrium sporulosum AP3s5-JAC2a. Mn(II)-oxidizing fungi are of engineering and industrial interest due to their utility in the remediation of metal-contaminated waters and their ability to harness Mn(II) oxidation in the breakdown of lignocellulosic plant material. While the processes of Mn(II) oxidation and carbon oxidation are mediated by the secretome in white-rot Basidiomycete fungi, comparatively little is known about the oxidative capacity of the secretomes of Ascomycetes, particularly those of environmental isolates. Using a combination of microscopy and chemical assays...

‣ On Reverse Engineering in the Cognitive and Brain Sciences

Schierwagen, Andreas
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 23/01/2012 Português
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Various research initiatives try to utilize the operational principles of organisms and brains to develop alternative, biologically inspired computing paradigms and artificial cognitive systems. This paper reviews key features of the standard method applied to complexity in the cognitive and brain sciences, i.e. decompositional analysis or reverse engineering. The indisputable complexity of brain and mind raise the issue of whether they can be understood by applying the standard method. Actually, recent findings in the experimental and theoretical fields, question central assumptions and hypotheses made for reverse engineering. Using the modeling relation as analyzed by Robert Rosen, the scientific analysis method itself is made a subject of discussion. It is concluded that the fundamental assumption of cognitive science, i.e. complex cognitive systems can be analyzed, understood and duplicated by reverse engineering, must be abandoned. Implications for investigations of organisms and behavior as well as for engineering artificial cognitive systems are discussed.; Comment: 19 pages, 5 figures