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| Registros recuperados: 2.284 | |
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| Shan-Huah Wu; Wei-Chun Chao; Chang-Fu Hsieh. |
| Spatial patterns of conspecific trees are considered as the consequences of biological interactions and environmental influences. They also reflect species interactions in plant communities. However, biological attributes are often neglected while deliberating the factors shaping species distributions. As rising attentions are paid to spatial patterns of tropical forest trees, we noticed that seven Center of Tropical Forest Sites and four Forest Dynamic Plots in Asia and America have presented analogously high proportions of species with aggregated conspecific individuals coincidently. This phenomenon is distinctive and repudiates fundamental ecology hypotheses which suggested dispersed distributions of conspecific tropical trees due to intensive density... |
| Tipo: Manuscript |
Palavras-chave: Ecology. |
| Ano: 2008 |
URL: http://precedings.nature.com/documents/1670/version/1 |
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| Hiroki Asari; Anthony M. Zador. |
| Acoustic processing requires integration over time. However classical linear encoding models, which typically integrate over a few hundred milliseconds, have failed to account fully for neural responses in the auditory cortex. We have used in vivo intracellular recording to measure neuronal integration times in anesthetized rats. Probing with natural sounds and other stimuli, we found that context-dependent effects in the primary auditory cortex could last for surprisingly long, up to four seconds or longer in some neurons. Thalamic neurons showed only a much faster form of adaptation, indicating that the long-lasting form originated in the cortex. Restricting knowledge of the stimulus history to only a few hundred milliseconds reduced the predictable... |
| Tipo: Manuscript |
Palavras-chave: Neuroscience. |
| Ano: 2008 |
URL: http://precedings.nature.com/documents/2282/version/1 |
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| Ajeet Ajeet. |
| The purpose of present work is to introduce the binding of existing drugs to the trans-disciplinary protein with the help of docking procedures. Docking procedures allows virtually screening a database of compounds and predict the strongest binder based on various scoring functions. This work has been performed with the help of Molegro Virtual docker, in which two drugs are docked with their corresponding and non-corresponding (trans-disciplinary) protein. Results reveals that the protein-ligand interaction energy, hydrogen bond energy and MolDock scores provided by molegro virtual docker, between legands (Levodopa and Acyclovir) and trans-disciplinary proteins have been equivalent or even better than that of between legands and corresponding proteins. |
| Tipo: Manuscript |
Palavras-chave: Pharmacology; Bioinformatics. |
| Ano: 2011 |
URL: http://precedings.nature.com/documents/6702/version/1 |
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| Pinar Wennerberg; Sonja Zillner. |
| Formal knowledge about human anatomy, radiology or diseases is necessary to support clinical applications such as medical image search. This machine processable knowledge can be acquired from biomedical domain ontologies, which however, are typically very large and complex models. Thus, their straightforward incorporation into the software applications becomes difficult. In this paper we discuss first ideas on a statistical approach for modularizing large medical ontologies and we prioritize the practical applicability aspect. The underlying assumption is that the application relevant ontology fragments, i.e. modules, can be identified by the statistical analysis of the ontology concepts in the domain corpus. Accordingly, we argue that most frequently... |
| Tipo: Manuscript |
Palavras-chave: Bioinformatics. |
| Ano: 2009 |
URL: http://precedings.nature.com/documents/3522/version/1 |
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| Sierra Rayne. |
| Sumac is the common name for a genus (Rhus) with >250 individual species of flowering plants in the family Anacardiaceae. These plants are globally distributed in temperate and tropical regions and can grow on marginal lands, making them strong candidates for renewable bioproduct sources. Despite the extensive historical use of some members of Rhus spp. for tannins and other commercial phenolics, little is known about the non-phenolic components of extracts and essentials oils. The current review highlights opportunities available to extend these limited prior studies to other sumac species, and for obtaining value-added compounds to complement already established phenolic extractions in these commercial plant species. To date, a number of... |
| Tipo: Manuscript |
Palavras-chave: Chemistry; Plant Biology. |
| Ano: 2011 |
URL: http://precedings.nature.com/documents/5926/version/1 |
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| Youn Jo Ko; Won Ho Jo. |
| Several prokaryotic ClC proteins have been demonstrated to function as exchangers that transport both chloride ions and protons simultaneously in opposite directions. However, the path of the proton through the ClC exchanger and how the protein brings about the coupled movement of both ions are still unknown. In the present work, we demonstrate that a previously unknown secondary water pore is formed inside a ClC exchanger by using an atomistic molecular dynamics (MD) simulation. From the systematic simulations, it was determined that the glutamate residue exposed to the intracellular solution, E203, plays an important role as a trigger for the formation of the secondary water pore. Based on our simulation results, we conclude that protons in the ClC... |
| Tipo: Manuscript |
Palavras-chave: Biotechnology; Chemistry. |
| Ano: 2008 |
URL: http://precedings.nature.com/documents/2168/version/1 |
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| Koji Inui; Tomokazu Urakawa; Koya Yamashiro; Naofumi Otsuru; Yasuyuki Takeshima; Ryusuke Kakigi. |
| The cortical mechanisms underlying echoic memory and change detection were investigated using an auditory change-related component (N100c) of event-related brain potentials. N100c was elicited by paired sound stimuli, a standard followed by a deviant, while subjects watched a silent movie. The amplitude of N100c elicited by a fixed sound pressure deviance (70 dB vs. 75 dB) was negatively correlated with the logarithm of the interval between the standard sound and deviant sound (1 ~ 1000 ms), while positively correlated with the logarithm of the duration of the standard sound (25 ~ 1000 ms), indicating that the temporal representation of echoic memory is logarithmic. The amplitude of N100c elicited by a deviance in sound pressure, sound frequency and sound... |
| Tipo: Manuscript |
Palavras-chave: Neuroscience. |
| Ano: 2009 |
URL: http://precedings.nature.com/documents/3652/version/1 |
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| Michael McCarthy; Colin Thompson; Hugh Possingham. |
| Conservation reserves are one of the most important tools for managing biodiversity. Ever since Diamond, based on theory of island biogeography, proposed that a single large reserve was preferable to several small reserves of the same total area, there has been an enduring debate about the veracity of his assertion. The so-called SLOSS debate - should we have a Single Large reserve Or Several Small reserves - features in every conservation text book and is central to conservation theory. Population dynamic models suggest that the design that minimizes the risk of extinction of species is case-specific, with the optimal number of reserves ranging between one and very many. Uncertainty is pervasive in ecology, but, the previous analyses of the SLOSS debate... |
| Tipo: Manuscript |
Palavras-chave: Ecology. |
| Ano: 2009 |
URL: http://precedings.nature.com/documents/3387/version/1 |
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| Jianhua Wang; Xuebin Zhang; Dayong Zhou; Qingguo Wang; Dan Li. |
| *Purpose:* To investigate the MR imaging of _Bifidobacterium longum_ and _Clostridium novyi-NT_ labeling with superparamagnetic iron oxide (SPIO) nanoparticles.

*Materials and methods:* Tubes containing _B. longum_-SPIO, Free-SPIO, _B. longum_ and PYG Medium were incubated under anaerobic condition in _in vitro_ experiment. Transmission electron microscope and Prussian blue staining were used to demonstrate intra-bacteria nanoparticles. R~2~^*^ mapping and R~2~ mapping were reconstructed after MR scanning. _B. longum_-SPIO and _C. novyi_-NT-SPIO were injected respectively _in vivo_ to show whether it might be traced by MR imaging.

*Results:* Magnetosomes in bacteria were observed by... |
| Tipo: Manuscript |
Palavras-chave: Biotechnology; Cancer; Microbiology. |
| Ano: 2009 |
URL: http://precedings.nature.com/documents/3435/version/1 |
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| Zhongtao Zhang. |
| Here I advance a hypothesis that neurodegeneration is a natural process associated with aging due to the loss of genetic redundancy following a mathematical model R(t) = R0(1-αe(βC+γI+δEt)t), where the calorie intake (C) and immune response (I) play critical roles. The early onset of neurodegenerative diseases such as Alzheimer’s disease is due to metabolic imbalance or chronic immune reactions to various infections. Therefore, the potential treatment options for neurodegenerative diseases are to modulate metabolism and immune response. |
| Tipo: Manuscript |
Palavras-chave: Neuroscience. |
| Ano: 2011 |
URL: http://precedings.nature.com/documents/6324/version/1 |
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| Meysam Shafiee Ardestani; Ebrahim Ghasemi-Nejad. |
| Abderaz Formation at its type section with an age of Turonian-early Campanian and a thickness of 300 m contains light grey shale and marl. The study of the planktonic foraminifera in isolated form led to differentiate three morphotype groups. The first group is characterized by trochospiral tests usually indicate shallow waters, the second group contains forms with strong ornamentations and the primary keels representing mid waters and finally compact trochospiral tests with keels known as deep water indices are included in the third group. Studies on the morphotypes showed a regressive cycle for Abderaz Formation. Also the planktonic to benthic ratio was calculated using Depth = e^(3.58718 + (0.03534 × %*p)^ equilibrium which explains that at the... |
| Tipo: Manuscript |
Palavras-chave: Ecology; Earth & Environment. |
| Ano: 2009 |
URL: http://precedings.nature.com/documents/2787/version/1 |
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| Andrey V. Zhuravlev. |
| Conodonts are considered now as specific group of early Chordata or even Vertebrata. Fifteen tooth-like conodont elements of seven morphological types compose the oral apparatus of conodonts. The elements demonstrate complex morphology. All the elements bear polygonal micro-ornamentation. The ornamentation is considered as representing imprints of the epithelium cells. Ecological dependencies of the cell sizes are known for some recent organisms.
The maximum cell sizes are characteristic of optimal environmental conditions. Thus, one can supposes that decreasing in cell imprint size in the conodonts marks disturbance in water temperature or/and oxygen content.
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| Tipo: Manuscript |
Palavras-chave: Earth & Environment. |
| Ano: 2007 |
URL: http://precedings.nature.com/documents/659/version/1 |
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| Xiaohan Yang; Gerald A. Tuskan; Timothy J. Tschaplinski; (Max) Zong-Ming Cheng. |
| Flowering plants (angiosperms) appeared on Earth rather suddenly approximately 130 million years ago and underwent a massive expansion in the subsequent 10-12 million years. Current molecular phylogenies have predominantly identified _Amborella_, followed by _Nymphaea_ (water lilies) or _Amborella_ plus _Nymphaea_, in the ANITA clade (_Amborella_, Nymphaeales, Illiciaceae, Trimeniaceae and Austrobaileyaceae) as the earliest angiosperm. However, developmental studies suggest that the earliest angiosperm had a 4-cell/4-nucleus female gametophyte and a diploid endosperm represented by _Nymphaea_, suggesting that _Amborella_, having an 8-cell/9-nucleus female gametophyte and a triploid endosperm, cannot be representative of the basal angiosperm. This... |
| Tipo: Manuscript |
Palavras-chave: Ecology; Plant Biology; Evolutionary Biology. |
| Ano: 2007 |
URL: http://precedings.nature.com/documents/320/version/1 |
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| Xiaolin Zhang. |
| The neuron, when considered as a signal processing device, itsinputs are the frequency of pulses received at the synapses, and its output is the frequency of action potentials generated- in essence, a neuron is a pulse frequency signal processing device. In comparison, electrical devices use either digital or analog signals for communication or processing, and the mathematics behind these subjects is well understood. However, in regards to pulse frequency processing devices, there has not yet been a clear and persuasive mathematical model to describe the functions of neurons. It goes without saying that such a model is very important, not only for understanding neuron and neural system behavior, but also for undeveloped potential applications in industry.... |
| Tipo: Manuscript |
Palavras-chave: Neuroscience. |
| Ano: 2008 |
URL: http://precedings.nature.com/documents/1703/version/1 |
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| Akhilesh V. Singh. |
| This study was undertaken to assess the potential of highly substitute acetylated sago starch (SS) to be used as a platform for controlled drug delivery. The acetylated sago starch was synthesized and the two parameters i.e. duration of reaction and temperature were optimized. FT-IR spectra showed the corresponding group attachment in the modified form. XRD pattern exhibits change in the physical nature i.e. from crystalline to amorphous. Swelling, hydration and viscosity value exhibits decrease in the respective values in comparison to its native form which is due a to decrease in its hydrophilic value. |
| Tipo: Manuscript |
Palavras-chave: Chemistry. |
| Ano: 2011 |
URL: http://precedings.nature.com/documents/5768/version/1 |
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| Registros recuperados: 2.284 | |
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