Últimos itens adicionados do Acervo: Proceedings Nature

Nature é uma das mais prestigiosas e antigas revistas científicas do mundo: sua primeira edição é de 4 de novembro de 1869. Entre as inúmeras descobertas científicas publicadas na Nature estão a dos raios X, da estrutura em dupla hélice do ADN e o buraco na camada de ozônio.

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‣ Double burden of malnutrition among urban Bengalee adolescent boys in Midnapore, West Bengal, India

S Bisai; R Khongsdier; K Bose; D Mahalanabis
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
Malnutrition is an important public health problem worldwide. Therefore a study was undertaken to assess the prevalence of adolescent thinness, overweight and obesity in Midnapore town, West Bengal, India. A total of 974 adolescent boys aged 10-18 years were selected following multistage cluster sampling method from three higher secondary schools. Data was collected using pretested questionnaire following standard technique. Presence of thinness was evaluated using the cut-off values of international survey as suggested by Cole et al (2007). While overweight and obesity was determine by using international cut-off values develop by Cole et al (2000) based on international surveys as recommended by IOTF. Overall the prevalence of thinness, overweight and obesity were 20.8%, 14.9% and 3.8%, respectively. This study developed age specific smooth BMI percentile values using LMS method. Moreover, the study also developed BMI cut-off values to define thinness, overweight and obesity. In conclusion, the present analyses indicated that the prevalence of adolescent undernutrition is still a major problem. In addition, there was also an emerging trend for overweight/obesity, thereby indicating a double burden of malnutrition as observed in other developing countries.

‣ Strong and weak competitors can coexist in the same niche

Lev V. Kalmykov; Vyacheslav L. Kalmykov
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
The competitive exclusion principle postulates that two trophically identical but fitness different species can not stably coexist in the same niche. However, this principle contradicts the observed nature's species richness. This fact is known as the biodiversity paradox. Here, using a simple cellular automaton model, we mechanistically show how two trophically identical, but fitness different species may stably coexist in the same niche. As environment is stable and any trade-offs are absent in this model, it strongly violates the competitive exclusion principle.

‣ Generalized Theory of Life

Vyacheslav L. Kalmykov
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
The paper is mathematically, physically and biologically inspired - it is a deductive attempt of the biologist to find the most appropriate language for modelling of life. Applications of mathematical structures - groupoids, groups, categories, functors and monads, which are the most effective for the description of the complex objects, are discussed. Some new conceptions and interpretations were introduced: unified classification of complex systems; the generalized conception about stationary states of any autonomous agent ("Statology"); the total quantitative criterions of evolutionary direction; the generalized group of symmetry. The definitions of information, entropy, organization, behavior, evolution, creation, life, culture, cognition were formulated. An actually closed and potentially opened ecosystem was introduced as the elementary object of organization and evolution of life. Evolution considered as process of generating of a concrete group G of permutations of elements of ecosystems, which is based on activities of the intrinsic autonomous agents. Life was considered as the way of realization of extreme principles of physics through co-organizing of behavior of the ecosystem elements and through dilating borders of the ecosystem by an interiorization of an extrinsic environment.

‣ Deletion of the rat trpc4 gene and its influence on motivated responding for natural reward

William D. Klipec; Bridget Deeney; Claire Williamson; Kami Wenzel; Phuong Nguyen; Eric Ostertag; Donald C. Cooper
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
TRPC4 ion channels are expressed extensively in corticolimbic brain regions and a subpopulation of midbrain dopamine neurons. TRPC4 knockout (KO) rats show reduced sociability and social exploration, but show no differences in simple and complex strategic learning compared to normal wild type (WT) rats. Using water reward, we found no differences between TRPC4-KO and WT rats in the break point on a progressive ratio schedule of reinforcement. Although deletion of the trpc4 gene alters social interaction/anxiety it does not appear to affect motivation for natural rewards. Current experiments are underway testing the role of trpc4 gene deletion on cocaine reward (see www.neuro-cloud.net/nature-precedings/klipec3 for updates and collaborations).

‣ Visual Molecular Dynamics Investigations of the Impact of Hydrophobic Nanoparticles on Prognosis of Alzheimer’s Disease and Cancers

I. C. Baianu; M Charles; V. I. Prisecaru
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
The possible impact of hydrophobic lectin nanoparticles on the prognosis and progression of Alzheimer's disease (AD) and cancers was investigated by Visual Molecular Dynamics (VMD) computer modeling programs available from the Beckmann Advanced Research Institute at the University of Illinois at Urbana. Our results indicate the possibility of impeding pathological aggregation of certain proteins such as modified tau- or beta-amyloid that are currently being considered as possible causes of Alzheimer's disease. VMD programs serve as useful tools for investigation hydrophobic protein aggregation that may play a role in aging of human populations.

‣ Angiogenesis in Chronic Obstructive Pulmonary Disease

Alessandro Matarese; Gaetano Santulli
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
Angiogenesis is a crucial component of lung pathophysiology, not only in cancer but also in other disorders, such as chronic obstructive pulmonary disease (COPD). In COPD angiogenesis is definitely able to control and orchestrate the progression of airway remodeling. Herein, we provide several remarkable translational aspects of angiogenesis in COPD, exploring both basic and clinical research in this field. Indeed, we present a number of pro- and anti-angiogenic factors, which can be also used as potential biomarkers to monitor disease progression. This pre-print has subsequently been published at http://www.unisa.it/uploads/7100/06.pdf

‣ Nonlinear Models of Neural and Genetic Network Dynamics

I. C. Baianu
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
A categorical and Łukasiewicz-Topos framework for Łukasiewicz LM-Algebraic Logic models of nonlinear dynamics in complex functional systems such as neural networks, genomes and cell interactomes is proposed. Łukasiewicz Algebraic Logic models of genetic networks and signaling pathways in cells are formulated in terms of nonlinear dynamic systems with n-state components that allow for the generalization of previous logical models of both genetic activities and neural networks.

‣ Inhaled Insulin: Intrapulmonary or Intranasal?

Danish Ahmed; Sweta Kumari; Shruti Mishra; Shivangi Jaiswal
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Poster
Português
Initial attempts delivered the insulin hormone intramuscularly, intravenously, and eventually subcutaneously. Other routes of administration of the drug were explored. These included oral, rectal, sublingual, buccal, transdermal, vaginal, intramuscular, intrapulmonary, and intranasal delivery systems. The purpose of these latter studies was to determine a noninjectable method to deliver insulin to patients with type 1 and 2 diabetes that would effectively lower blood sugar, control hemoglobin A1c (in much later studies), and allow patients a simpler, less invasive, and more direct control oftheir underlying disease process. In January 2006 the United States Food and Drug Administration approved Exubera (Pfizer Pharmaceuticals, New York, NY) as the first pulmonary inhaled insulin. In actuality attempts to explore various methods to deliver insulin using intrapulmonary delivery had occurred since1925.

‣ Chloroplast and Cell Imaging at Submicron Resolution by Two-Photon Excitation

I C. Baianu
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
Novel, two-photon NIR excitation fluorescence correlation microspectroscopy tests and preliminary results were presented in this article with submicron resolution for concentrated suspensions of functional cells and chloroplast membranes. Related developments of these technique involve applications of Fluorescence Cross-Correlation Spectroscopy (FCCS) detection to monitoring: DNA- telomerase interactions, DNA hybridization kinetics, ligand-receptor interactions, and HIV-HBV testing.

‣ From Machine Learning to Learning Machines - A Perspective toward Personalized Medicine

Malay Bhattacharyya
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Português
We describe how to learn a network using a bottom-up approach by building networks from expression profiles. Then we can analyze these networks with different graph mining approaches and by studying topological behaviors. Finally, how we can achieve personalized medicine from the network biology.

‣ Mining Co-expression Graphs: Applications to MicroRNA Regulation and Disease Analysis

Malay Bhattacharyya
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Português
MicroRNAs (miRNAs) are known to translationally repress or post-transcriptionally regulate mRNAs and are responsible for many diseases. We are preparing a comprehensive framework of co-expression analysis to figure out co-expression, differential co-expression and co-expression dynamics within multiple phenotypes in expression profiles. The purpose is to elucidate the disease association of miRNAs via co-regulatory pattern analysis.

‣ Some Concepts of Graph Theory

Malay Bhattacharyya
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Português
We present some preliminary concepts of graph theory with interesting and easy examples.

‣ Fundamentals of Molecular Biology

Malay Bhattacharyya
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Português
We present some basic concepts of molecular biology and the related open problems.

‣ Mapping from Statistical to Biological Proximity

Malay Bhattacharyya
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Português
We verify whether the proximity claimed by state-of-the-art statistical similarity measures are indeed biologically appropriate or not. We present some analytical results on it.

‣ Co-expression Toggling of MicroRNAs in Alzheimer’s Brain

Malay Bhattacharyya
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Poster
Português
We present the findings on how microRNA expression profiles changes in Alzheimer's brain.

‣ Better Analysis, Better Acceptance ‐Take up the Challenge of Publishing in Bioinformatics

Malay Bhattacharyya
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Português
This presentation teaches the novice in bioinformatics research to publish quality analysis in good venues.

‣ Mining the Largest Quasi-clique in Human Protein Interactome

Sanghamitra Bandyopadhyay; Malay Bhattacharyya
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Português
A clique is a complete subgraph of a graph. Often, a clique is interpreted as a dense module of vertices within a graph. However, in many real-world situations, the classical problem of finding a clique is required to be relaxed. This motivates the problem of finding quasicliques that are almost complete subgraphs of a graph. In sparse and very large scale-free networks, the problem of finding the largest quasi-clique becomes hard to manage with the existing approaches. Here, we propose a heuristic algorithm in this paper for locating the largest quasi-clique from the human protein-protein interaction networks. The results show promise in computational biology research by the exploration of significant protein modules.

‣ Integration of Co-expression Networks for Gene Clustering

Malay Bhattacharyya; Sanghamitra Bandyopadhyay
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Conferência ou Objeto de Conferência
Português
Simultaneous overexpression or underexpression of multiple genes, used in various forms as probes in the high-throughput microarray experiments, facilitates the identification of their underlying functional proximity. This kind of functional associativity (or conversely the separability) between the genes can be represented proficiently using co-expression networks. The extensive repository of diversified microarray data encounters a recent problem of multi-experimental data integration for the aforesaid purpose. This paper highlights a novel integration method of gene co-expression networks, based on the search for their consensus network, derived from diverse microarray experimental data for the purpose of clustering. The proposed methodology avoids the bias arising from missing value estimation. The method has been applied on microarray datasets arising from different category of experiments to integrate them. The consensus network, thus produced, reflects robustness based on biological validation.

‣ Kinetic resolution of racemates under chiral catalysis: connecting the dots

Sosale Chandrasekhar
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
The current theory of the titled phenomenon is apparently based on an inconsistent use of concentration units, as employed in the derivation of the fundamental equations. Thus, manifestly, whilst the relation between extent of conversion and e.e. is derived with mole fractions, the succeeding kinetic equations employ units of molarity. This invalidates the derivation in the general case. Fortuitously, however, it is applicable in the majority of simple cases, wherein the total number of moles involved in the reaction remains constant. Herein is presented a rigorous approach which is generally valid.

‣ Synchronized Mammalian Cells in Culture: A Comparison of Normal and KB Cancer Cell Growth

I. C. Baianu
Fonte: Nature Preceedings Publicador: Nature Preceedings
Tipo: Manuscript
Português
Experimentation and tests with cells in culture and cell synchronization or synchrony are important in order to be able to make both reliable and high-sensitivity measurements. This is also very important for mechanistic studies of cell division control, oncogenesis and tumor growth. A comparison is made in this article between the initially synchronized cell growth of rabbit and KB cells in synchronized cultures.