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A New General Allometric Biomass Model Nature Precedings
Wei Sheng Zeng; Shou Zheng Tang.
To implement monitoring and assessment of national forest biomass, it is becoming the trend to develop generalized single-tree biomass models suitable for large scale forest biomass estimation. Considering that the theoretical biomass allometric model developed by West et al. [1,2] was statistically different from the empirical one, the two parameters in the most commonly used biomass equation M=aDb were analyzed in this paper. Firstly, based on the knowledge of geometry, the theoretical value of parameter b was deduced, i.e., b=7/3(~2.33), and the comparison with many empirical studies conducted throughout the globe indicated that the theoretical parameter could describe soundly the average allometric relationship between aboveground biomass M and D...
Tipo: Manuscript Palavras-chave: Ecology.
Ano: 2011 URL: http://precedings.nature.com/documents/6704/version/2
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A New General Allometric Biomass Model Nature Precedings
Wei Sheng Zeng; Shou Zheng Tang.
To implement monitoring and assessment of national forest biomass, it is becoming the trend to develop generalized single-tree biomass models suitable for large scale forest biomass estimation. Considering that the theoretical biomass allometric model developed by West et al. [1,2] was statistically different from the empirical one, the two parameters in the most commonly used biomass equation M=aDb were analyzed in this paper. Firstly, based on the knowledge of geometry, the theoretical value of parameter b was deduced, i.e., b=7/3(≈2.33), and the comparison with many empirical studies conducted throughout the globe indicated that the theoretical parameter could describe soundly the average allometric relationship between aboveground biomass M...
Tipo: Manuscript Palavras-chave: Ecology.
Ano: 2011 URL: http://precedings.nature.com/documents/6704/version/1
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A new mathematical model for radiation cell killing mechanism: Target cumulating model Nature Precedings
Zhao Liang; Wu Shixiu; Xie Congyin; Zhang Li.
There are numerous mathematical or statistical models have been given out for radiation cell killing mechanism. Unfortunately, none of the model could explain the mechanism perfectly. The more advanced model for it is still necessary to be researched. Following common assumption, a new theoretical model named "target cumulating" model is induced from the molecular and particle physics level. The result of theoretical calculation gives the equation of cell survival rate corresponding to delivered dose and other sensitivity parameters. In addition to fit the cell survival curve well, the new model showed advantages with comparing to previous models. Also, the new model predicts or explains some phenomenon that had been observed in...
Tipo: Manuscript Palavras-chave: Cancer.
Ano: 2009 URL: http://precedings.nature.com/documents/2880/version/1
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A New Method for Characterization of Natural Zeolites and Organic Nanostructure using Atomic Force Microscopy Nature Precedings
Domenico P. R. O. F. Fuoco.
In order to study and develop an economic solution to environmental pollution in water, a wide variety of materials were investigated. Natural zeolites emerge from that research as the best in class of this category. Zeolites are natural materials relatively abundant and non biodegradable, economic and good to perform processes of environmental remediation. This paper contains a full description of a new method to characterize superficial properties of natural zeolites of exotic provenience (Caribbean Islets) with atomic force microscopy (AFM). AFM works with the optical microscope simplicity and the high resolution typical of a transmission electron microscope (TEM). Structural information of mesoporous material is obtained using scanning and transmission...
Tipo: Manuscript Palavras-chave: Chemistry.
Ano: 2012 URL: http://precedings.nature.com/documents/6828/version/1
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A new multicompartmental reaction-diffusion modeling method links transient membrane attachment of E. coli MinE to E-ring formation Nature Precedings
Satya N. V. Arjunan; Masaru Tomita.
Many important cellular processes are regulated by reaction-diffusion (RD) of molecules that takes place both in the cytoplasm and on the membrane. To model and analyze such multicompartmental processes, we developed a lattice-based Monte Carlo method, Spatiocyte that supports RD in volume and surface compartments at single molecule resolution. Stochasticity in RD and the excluded volume effect brought by intracellular molecular crowding, both of which can significantly affect RD and thus, cellular processes, are also supported. We verified the method by comparing simulation results of diffusion, irreversible and reversible reactions with the predicted analytical and best available numerical solutions. Moreover, to directly compare the localization...
Tipo: Manuscript Palavras-chave: Developmental Biology; Microbiology; Bioinformatics.
Ano: 2009 URL: http://precedings.nature.com/documents/3845/version/1
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A new outlook towards kidney injuries Nature Precedings
Mahesh Satwekar; Abhijeet Satwekar.
Acute and chronic progression of injury to the kidney leads to the failure of the renal system and has become an increasingly important cause of morbidity and mortality. Present diagnosis detects the condition only after irreversible loss of 70 percent of kidney function. Current research is focused only on the clinical manifestations after the kidney injuries and not towards the exact cause of the condition. Here we propose a new outlook- that there is an involvement of a pathogen in the pathogenesis of kidney injuries. Basis for our proposal is given by the similarity of the pathogenesis events occurring between a classical example of hepatitis and kidney injuries. Furthermore, literature regarding the role of early kidney injury biomarkers in innate...
Tipo: Manuscript Palavras-chave: Biotechnology; Immunology; Microbiology.
Ano: 2012 URL: http://precedings.nature.com/documents/7021/version/1
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A new phylogenetic comparative method: detecting niches and transitions with continuous characters Nature Precedings
Carl Boettiger.
Traditional information criteria approaches can lead to misleading model choice in comparative phylogenetics. I present examples of these weaknesses using a classic data set on Anoles lizards. I describe a more robust comparison by likelihood ratio. I then discuss a new class of models to capture the transition process between evolutionary regimes.
Tipo: Presentation Palavras-chave: Bioinformatics; Evolutionary Biology.
Ano: 2010 URL: http://precedings.nature.com/documents/4615/version/1
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A new potential radiosensitizer: ammonium persulfate modified WCNTs Nature Precedings
Jian-She Yang; Bo-Zhang Yu; Wen-Xin Li.
Radiotherapy plays a very important role in cancer treatment. Radiosensitizers have been widely used to enhance the radiosensitivity of cancer cells at given radiations. Here we fabricate multi-walled carbon nanotubes with ammonium persulfate, and get very short samples with 30-50 nanometer length. Cell viability assay show that f-WCNTs induce cell death significantly. We hypothesize that free radicals originated from hydroxyl and carbonyl groups on the surface of f-WCNTs lead cell damage.
Tipo: Manuscript Palavras-chave: Biotechnology; Cancer; Chemistry.
Ano: 2007 URL: http://precedings.nature.com/documents/1421/version/1
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A normalization technique for next generation sequencing experiments Nature Precedings
Günter Klambauer; Karin Schwarzbauer; Andreas Mayr; Sepp Hochreiter.
Next generation sequencing (NGS) are these days one of the key technologies in biology. NGS' cost effectiveness and capability of finding the smallest variations in the genome makes them increasingly popular. For studies aiming at genome assembly, differences in read count statistics do not affect the outcome. However, these differences bias the outcome if the goal is to identify structural DNA characteristics like copy number variations (CNVs). Thus a normalization step must removed such random read count variations subsequently read counts from different experiments are comparable. Especially after normalization the commonly used assumption of Poisson read count distribution in windows on the chromosomes is more justified. Strong deviations of...
Tipo: Poster Palavras-chave: Genetics & Genomics; Molecular Cell Biology; Bioinformatics.
Ano: 2010 URL: http://precedings.nature.com/documents/4710/version/1
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A normalization technique for next generation sequencing experiments Nature Precedings
Günter Klambauer; Karin Schwarzbauer; Andreas Mayr; Sepp Hochreiter.
Next generation sequencing (NGS) are these days one of the key technologies in biology. NGS' cost effectiveness and capability of finding the smallest variations in the genome makes them increasingly popular. For studies aiming at genome assembly, differences in read count statistics do not affect the outcome. However, these differences bias the outcome if the goal is to identify structural DNA characteristics like copy number variations (CNVs). Thus a normalization step must removed such random read count variations subsequently read counts from different experiments are comparable. Especially after normalization the commonly used assumption of Poisson read count distribution in windows on the chromosomes is more justified. Strong deviations of...
Tipo: Poster Palavras-chave: Genetics & Genomics; Molecular Cell Biology; Bioinformatics.
Ano: 2010 URL: http://precedings.nature.com/documents/4710/version/2
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A Note on Measures of Single Timeseries Activity in Resting-State fMRI Studies Nature Precedings
Xi-Nian Zuo.
In statistics, signal processing and mathematical finance, a time series is a sequence of data points, measured typically at successive times spaced at uniform time intervals. Here, I only focus on the discrete time series. The motivation of writing this methodology note is to clarify the relationship between the measures to quantify activity of an observed timeseries. Particularly, focus one several measures used in recently emerged field of resting-state fMRI studies. Although all these measures have been extensively developed in EEG or other timeseries studies, many researchers focusing on various applications in or new comers to this new field need to know existed measures and the relationships among these measures.
Tipo: Manuscript Palavras-chave: Neuroscience; Bioinformatics.
Ano: 2010 URL: http://precedings.nature.com/documents/4379/version/1
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A Note On The Denisova Cave mtDNA Sequence Nature Precedings
Niccolo Caldararo.
The recently published Altai fossil sequence from Denisova Cave was purported to be so different from anatomically modern humans, yet have the physiological landmarks of that species designation. When the published sequence was examined it was found that segments in the mtDNA hypervariable regions could be found to align with that of anatomically modern humans if one introduced an insertion at a position found in Neanderthals. Some other points of interest arise from a reconsideration of the sequences for other published samples and Neanderthals from the same perspective.
Tipo: Manuscript Palavras-chave: Evolutionary Biology.
Ano: 2010 URL: http://precedings.nature.com/documents/5360/version/1
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A Note On The Denisova Cave mtDNA Sequence Nature Precedings
Niccolo Caldararo; Michael Guthrie.
The recently published Altai fossil sequence from Denisova Cave was purported to be so different from anatomically modern humans, yet have the physiological landmarks of that species designation. When the published sequence was examined it was found that segments in the mtDNA hypervariable regions could be found to align with that of anatomically modern humans if one introduced an insertion at a position found in Neanderthals. Some other points of interest arise from a reconsideration of the sequences for other published samples and Neanderthals from the same perspective.
Tipo: Manuscript Palavras-chave: Genetics & Genomics; Evolutionary Biology.
Ano: 2011 URL: http://precedings.nature.com/documents/5360/version/3
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A Note On The Denisova Cave mtDNA Sequence Nature Precedings
Niccolo Caldararo; Michael Guthrie.
The recently published Altai fossil sequence from Denisova Cave was purported to be so different from anatomically modern humans, yet have the physiological landmarks of that species designation. When the published sequence was examined it was found that segments in the mtDNA hypervariable regions could be found to align with that of anatomically modern humans if one introduced an insertion at a position found in Neanderthals. Some other points of interest arise from a reconsideration of the sequences for other published samples and Neanderthals from the same perspective.
Tipo: Manuscript Palavras-chave: Genetics & Genomics; Evolutionary Biology.
Ano: 2012 URL: http://precedings.nature.com/documents/5360/version/4
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A Note On The Denisova Cave mtDNA Sequence Nature Precedings
Niccolo Caldararo; Michael Guthrie.
The recently published Altai fossil sequence from Denisova Cave was purported to be so different from anatomically modern humans, yet have the physiological landmarks of that species designation. When the published sequence was examined it was found that segments in the mtDNA hypervariable regions could be found to align with that of anatomically modern humans if one introduced an insertion at a position found in Neanderthals. Some other points of interest arise from a reconsideration of the sequences for other published samples and Neanderthals from the same perspective.
Tipo: Manuscript Palavras-chave: Genetics & Genomics; Evolutionary Biology.
Ano: 2011 URL: http://precedings.nature.com/documents/5360/version/2
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A novel alveolar Krebs cycle-triggered CO2 sensing mechanism regulates regional pulmonary ventilation. Nature Precedings
Rainer Kiefmann; Paula Keller; Oliver Tritt; Kai Heckel; Sascha Tank; Martina Kiefmann; Leoni Schulte-Uentrop; Alwin Goetz.
Pulmonary perfusion disorders provoke atelectasis in order to minimize ventilation/perfusion mismatch. However, the underlying mechanisms remain unknown. Because intraalveolar CO2 concentration ([CO2]iA) declines as a consequence of poor pulmonary perfusion we postulated the existence a novel alveolar CO2-sensing mechanism which adapts the ventilation to perfusion. Real-time fluorescence imaging of rat lungs revealed that low [CO2]iA decreased cytosolic and increased mitochondrial Ca2+ in alveolar epithelial cells (AEC), leading to reduction of surfactant secretion and alveolar ventilation. Mitochondrial inhibition by ruthenium red or rotenone blocked the hypocapnia-induced responses. In cultured Type 2 AEC hypocapnia decreased cytosolic Ca2+ independently...
Tipo: Manuscript Palavras-chave: Molecular Cell Biology.
Ano: 2011 URL: http://precedings.nature.com/documents/6185/version/1
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A novel apparatus/protocol designed for optogenetic manipulation and recording of individual neurons during a motivation and working memory task in the rodent Nature Precedings
Samuel Dolzani; Donald C. Cooper.
Innovative molecular tools allow neuroscientists to study neural circuitry associated with specific behaviors. Consequently, behavioral methods must be developed to interface with these new molecular tools in order for neuroscientists to identify the causal elements underlying behavior and decision-making processes. Here we present an apparatus and protocol for a novel Go/No-Go behavioral paradigm to study the brain attention and motivation/reward circuitry in awake, head-restrained rodents. This experimental setup allows: (1) Painless and stable restraint of the head and body; (2) Rapid acquisition to simple or complex operant tasks; (3) Repeated electrophysiological single and multiple unit recordings during ongoing behavior; (4) Pharmacological and...
Tipo: Manuscript Palavras-chave: Neuroscience; Pharmacology.
Ano: 2012 URL: http://precedings.nature.com/documents/7152/version/1
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A novel class of endogenous shRNAs in human cells Nature Precedings
Tongjun Gu; James Q. Yin; Yanwei Xu; ZhengHua Dai; Zhengge Qiu; Shenzhong Feng; Xiang Yi; Ling Jiang; Hongjie Zhang.
Until now it is still not clear how many types and amounts of small RNAs (sRNAs) exist in humans. Here we report the identification of 1258 distinct sRNAs derived from intronic regions of protein-coding genes in human with a new approach. These endogenous short hairpin RNAs (shRNAs) appear to be similar to exogenous shRNAs in structure, have a broad distribution in the stem length, and function as microRNAs (miRNAs), small interfering RNAs (siRNA) and/or piwi-interacting RNAs (piRNAs). Except for a few shRNAs, the majority of shRNAs are not phylogenetically conserved. They are differentially expressed in different cells and at diverse developmental stages. Overall, their expression levels are lower than miRNAs', but can be detected by quantitative...
Tipo: Manuscript Palavras-chave: Biotechnology.
Ano: 2008 URL: http://precedings.nature.com/documents/1531/version/1
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A novel _Drosophila_ post-genomic CNS drug discovery model detects tetraethylammonium chloride with therapeutic potential Nature Precedings
Priyanka Singh; Farhan Mohammad*; Abhay Sharma.
A _Drosophila_ behavioral and transcriptomic model of locomotor plasticity induced by chronic pentylenetetrazole (PTZ) has recently been developed. In this model, two of the five antiepileptic drugs (AEDs) tested, sodium valproate (NaVP) and levetiracetam (LEV), not ethosuximide (ETH), gabapentin (GBP) and vigabatrin (VGB), ameliorate development of chronic PTZ induced locomotor alteration. Transcriptomic effect of the AEDs and PTZ in fly head has been described. Here, we analyze microarray expression profile of heads of flies treated with the convulsants tetraethylammonium chloride (TEA) and pilocarpine hydrochloride (PILO). Strikingly, microarray clustering placed TEA, not PILO, with LEV and NaVP in one group that was distinct from the other one...
Tipo: Manuscript Palavras-chave: Genetics & Genomics; Neuroscience; Pharmacology; Bioinformatics.
Ano: 2009 URL: http://precedings.nature.com/documents/3418/version/1
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A novel Drosophila transcriptomic and behavioral model detects potassium chloride with therapeutic potential Nature Precedings
Farhan Mohammad; Priyanka Singh; Abhay Sharma.
In a newly described _Drosophila_ model, two of the five antiepileptic drugs (AEDs) tested, sodium valproate (NaVP) and levetiracetam (LEV), not ethosuximide (ETH), gabapentin (GBP) and vigabatrin (VGB), ameliorate development of chronic pentylenetetrazole (PTZ) induced locomotor alteration. To further characterize the model, we analyze here the microarray expression profile of heads of flies treated with depolarizing compound potassium chloride (KCl). Surprisingly, microarray clustering showed unexpected similarity among KCl, LEV and NaVP. Further, like the two effective AEDs in the fly model, KCl regulated genes overrepresented ribosomal pathway. Interestingly, KCl also ameliorated development of locomotor deficit in the chronic PTZ model. Both...
Tipo: Manuscript Palavras-chave: Genetics & Genomics; Neuroscience; Pharmacology; Bioinformatics.
Ano: 2009 URL: http://precedings.nature.com/documents/3429/version/1
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