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Full-Text Articles in Physical Sciences and Mathematics

Modeling In Microbial Batch Culture And Its Parameter Identification, Zhaohua Gong, Chongyang Liu, Enmin Feng Nov 2009

Modeling In Microbial Batch Culture And Its Parameter Identification, Zhaohua Gong, Chongyang Liu, Enmin Feng

Chongyang Liu

In this paper, the nonlinear dynamical system of batch fermentation is investigated in the bioconversion of glycerol to 1,3-propanediol(1,3-PD) by Klebsiella pneumoniae. Taking account of the kinetic behavior and experimental results in the batch cultures, we propose a two-stage dynamical system to formulate the fermentation process. Then some properties of the proposed system are proved. In view of the big errors between observations and numerical simulation results, we subsequently establish a parameter identification model to identify parameters in the system. The identifiability of the model is also discussed. Finally, in order to find the optimal parameters of the identification model, …


Estructura Y Composición Florística Del Bosque De La Llanura Aluvial En La Amazonía Peruana: I. El Bosque Alto, Gustav Nebel, Lars Peter Kvist, Jerome K. Vanclay, Henning Christensen, Luis Freitas, Juan Ruiz Nov 2009

Estructura Y Composición Florística Del Bosque De La Llanura Aluvial En La Amazonía Peruana: I. El Bosque Alto, Gustav Nebel, Lars Peter Kvist, Jerome K. Vanclay, Henning Christensen, Luis Freitas, Juan Ruiz

Professor Jerome K Vanclay

Three peruvian flood plain forests adjacent to the Ucayali river were sampled using nine one hectare permanent sample plots in which stems exceeding 10 cm DBH were identified and measured. These plots have been measured 4 times during 1993- 1997, and provide the basis for the results reported here. Three plots were established in each of the three forest types high restinga, low restinga, and tahuampa, characterized in part by and annual inundation of 1, 2 and 4 months per year, respectively. Stem density varies from 446 to 601 per ha, and the basal area ranges between 20-29 m2/ha. A …


Estructura Y Composición Florística Del Bosque De La Llanura Aluvial Inundable De La Amazonía Peruana: Ii. El Sotobosque De La Restinga, Gustav Nebel, Jens Dragsted, Jerome K. Vanclay Nov 2009

Estructura Y Composición Florística Del Bosque De La Llanura Aluvial Inundable De La Amazonía Peruana: Ii. El Sotobosque De La Restinga, Gustav Nebel, Jens Dragsted, Jerome K. Vanclay

Professor Jerome K Vanclay

Structure and floristic composition of small trees and shrubs (1.5 m height to 10 cm DBH) are described in two flood plain forests of the lower Ucayali river, Peruvian Amazon. The forests are of high and low restinga type, on an annual average flooded around 1 and 2 months, respectively. The soils are nutrients rich entisolls, and the vegetation forms closed high canopy forests with presence of emergents. A total of 25 permanent sample plots covering 0.64 ha were established. They are nested within six quadratic one-hectare permanent sample plots where large individuals (>= 10 cm DBH) were inventoried. …


Functional Transition In The Floral Receptacle Of The Sacred Lotus (Nelumbo Nucifera): From Thermogenesis To Photosynthesis, R. E. Miller, J. R. Watling, Sharon A. Robinson Nov 2009

Functional Transition In The Floral Receptacle Of The Sacred Lotus (Nelumbo Nucifera): From Thermogenesis To Photosynthesis, R. E. Miller, J. R. Watling, Sharon A. Robinson

Sharon Robinson

The receptacle of the sacred lotus is the main source of heat during the thermogenic stage of floral development. Following anthesis, it enlarges, greens and becomes a fully functional photosynthetic organ. We investigated development of photosynthetic traits during this unusual functional transition. There were two distinct phases of pigment accumulation in receptacles. Lutein and photoprotective xanthophyll cycle pigments accumulated first with 64% and 95% of the maximum, respectively, present prior to anthesis. Lutein epoxide comprised 32% of total carotenoids in yellow receptacles, but declined with development. By contrast, more than 85% of maximum total chlorophyll, β-carotene and Rubisco were produced …


Responses Of Plants In Polar Regions To Uvb Exposure : A Meta-Analysis, K. K. Newsham, Sharon A. Robinson Nov 2009

Responses Of Plants In Polar Regions To Uvb Exposure : A Meta-Analysis, K. K. Newsham, Sharon A. Robinson

Sharon Robinson

We report a meta-analysis of data from 34 field studies into the effects of UV-B radiation on Arctic and Antarctic bryophytes and angiosperms. The studies measured plant responses to decreases in UV-B radiation under screens, natural fluctuations in UV-B irradiance, or increases in UV-B radiation applied from fluorescent UV lamps. Exposure to UV-B radiation was found to increase the concentrations of UV-B absorbing compounds in leaves or thalli by 7% and 25% (expressed on a mass or area basis, respectively). UV-B exposure also reduced aboveground biomass and plant height by 15% and 10%, respectively, and increased DNA damage by 90%. …


Genetic Structure Of East Antarctic Populations Of The Moss Ceratodon Purpureus, L. J. Clarke, D. J. Ayre, Sharon A. Robinson Nov 2009

Genetic Structure Of East Antarctic Populations Of The Moss Ceratodon Purpureus, L. J. Clarke, D. J. Ayre, Sharon A. Robinson

Sharon Robinson

The capacity of the polar flora to adapt is of increasing concern given current and predicted environmental change in these regions. Previous genetic studies of Antarctic mosses have been of limited value due to a lack of variation in the markers or non-specificity of the methods used. We examined the power of five microsatellite loci developed for the cosmopolitan moss Ceratodon purpureus to detect genetically distinct clones and infer the distribution of clones within and among populations from the Windmill Islands, East Antarctica. Our microsatellite data suggest extraordinarily high levels of variation reported in RAPD studies were artificially elevated by …


Two Cys Or Not Two Cys? That Is The Question; Alternative Oxidase In The Thermogenic Plant Sacred Lotus, Nicole M. Grant, Yoshihiko Onda, Yusuke Kakizaki, Kkikukatsu Ito, Jennifer R. Watling, Sharon A. Robinson Nov 2009

Two Cys Or Not Two Cys? That Is The Question; Alternative Oxidase In The Thermogenic Plant Sacred Lotus, Nicole M. Grant, Yoshihiko Onda, Yusuke Kakizaki, Kkikukatsu Ito, Jennifer R. Watling, Sharon A. Robinson

Sharon Robinson

Sacred lotus (Nelumbo nucifera) regulates temperature in its floral chamber to 32°C to 35°C across ambient temperatures of 8°C to 40°C with heating achieved through high alternative pathway fluxes. In most alternative oxidase (AOX) isoforms, two cysteine residues, Cys1 and Cys2, are highly conserved and play a role in posttranslational regulation of AOX. Further control occurs via interaction of reduced Cys1 with α-keto acids, such as pyruvate. Here, we report on the in vitro regulation of AOX isolated from thermogenic receptacle tissues of sacred lotus. AOX protein was mostly present in the reduced form, and only a small fraction could …


Indicator Groups And Faunal Richness, Jerome K. Vanclay Oct 2009

Indicator Groups And Faunal Richness, Jerome K. Vanclay

Professor Jerome K Vanclay

Species richness is a popular indicator of ecosystem vitality, but is difficult to assess. Many natural resource managers seek an efficient bioindicator, but the link between candidate indicators and the richness of other taxononic groups remains elusive. A series of faunal surveys in the Mbalmayo Forest Reserve in Cameroon suggest that it may be possible to devise faunal bioindicators. The species richness of birds, of butterflies and of termites is significantly correlated with total faunal richness across eight species groups, suggesting that these groups may have potential as bioindicators, alone or in combination. Although expensive, further research is warranted because …


Site Index Equation For Smallholder Plantations Of Gmelina Arborea In Leyte Province, The Philippines, Jerome K. Vanclay, Jack Baynes, Edwin Cedamon Oct 2009

Site Index Equation For Smallholder Plantations Of Gmelina Arborea In Leyte Province, The Philippines, Jerome K. Vanclay, Jack Baynes, Edwin Cedamon

Professor Jerome K Vanclay

The equation SiteIndex = Height × Log(IndexYear+0.5) / Log(Age+0.5) is suggested as a robust way to classify site index of small private Gmelina arborea plantations in Leyte province in the Philippines. Estimates of site index from this equation correlate well with other indicators of site productivity, including the observed mean annual volume increment and soil depth. An alternative equation based on slope and soil depth offers an indication of potential site productivity on unforested sites where no crop trees are present.


Managing Water Use From Forest Plantations, Jerome K. Vanclay Oct 2009

Managing Water Use From Forest Plantations, Jerome K. Vanclay

Professor Jerome K Vanclay

Tree plantations have developed a reputation for excessive water use, with age commonly used as an explanatory variable to predict water loss – but many factors have the potential to affect plantation water use, and few of these alternatives have been considered. Changes in forest cover may be correlated with other environmental changes that may affect precipitation, transpiration, and runoff, indicating that more thorough investigation is required in both field and simulation studies. Several factors influencing water use by plantations are amenable to management control, so there is scope to design and manage forest plantations deliberately for water use efficiency. …


Integrative Analysis Of Cancer Genomic Data, Shuangge Ma Sep 2009

Integrative Analysis Of Cancer Genomic Data, Shuangge Ma

Shuangge Ma

In the past decade, we have witnessed a period of unparallel development in the field of cancer genomics. To address the same or similar biomedical questions, multiple cancer genomic studies have been independently designed and conducted. Cancer gene signatures identified from analysis of individual datasets often have low reproducibility. A cost-effective way of improving reproducibility is to conduct integrative analysis of datasets from multiple studies with comparable designs. To properly integrate multiple studies and conduct integrative analysis, we need to access various public data warehouses, retrieve experiment protocols and raw data, evaluate individual studies and select those with comparable designs, …


Multiple Loci Within The Major Histocompatibility Complex Confer Risk Of Psoriasis, Bing-Jian Feng, Liang-Dan Sun, Razieh Soltani-Arabshahi, Anne M. Bowcock, Rajan P. Nair, Philip Stuart, James T. Elder, Steven J. Schrodi, Ann B. Begovich, Goncalo R. Abecasis, Xue-Jun Zhang, Kristina P. Callis Duffin, Gerald G. Krueger, David E. Goldgar Jul 2009

Multiple Loci Within The Major Histocompatibility Complex Confer Risk Of Psoriasis, Bing-Jian Feng, Liang-Dan Sun, Razieh Soltani-Arabshahi, Anne M. Bowcock, Rajan P. Nair, Philip Stuart, James T. Elder, Steven J. Schrodi, Ann B. Begovich, Goncalo R. Abecasis, Xue-Jun Zhang, Kristina P. Callis Duffin, Gerald G. Krueger, David E. Goldgar

Steven J Schrodi

Psoriasis is a common inflammatory skin disease characterized by thickened scaly red plaques. Previously we have performed a genome-wide association study (GWAS) on psoriasis with 1,359 cases and 1,400 controls, which were genotyped for 447,249 SNPs. The most significant finding was for SNP rs12191877, which is in tight linkage disequilibrium with HLA-Cw*0602, the consensus risk allele for psoriasis. However, it is not known whether there are other psoriasis loci within the MHC in addition to HLA-C. In the present study, we searched for additional susceptibility loci within the human leukocyte antigen (HLA) region through in-depth analyses of the GWAS data; …


Triangle Network Motifs Predict Complexes By Complementing High-Error Interactomes With Structural Information, Bill Andreopoulos, Christof Winter, Dirk Labudde, Michael Schroeder Jun 2009

Triangle Network Motifs Predict Complexes By Complementing High-Error Interactomes With Structural Information, Bill Andreopoulos, Christof Winter, Dirk Labudde, Michael Schroeder

William B. Andreopoulos

Background
A lot of high-throughput studies produce protein-protein interaction networks (PPINs) with many errors and missing information. Even for genome-wide approaches, there is often a low overlap between PPINs produced by different studies. Second-level neighbors separated by two protein-protein interactions (PPIs) were previously used for predicting protein function and finding complexes in high-error PPINs. We retrieve second level neighbors in PPINs, and complement these with structural domain-domain interactions (SDDIs) representing binding evidence on proteins, forming PPI-SDDI-PPI triangles.

Results
We find low overlap between PPINs, SDDIs and known complexes, all well below 10%. We evaluate the overlap of PPI-SDDI-PPI triangles with …


A Tale Of Two Streets: Incorporating Grouping Structure In High Dimensional Data Mining, Shuangge Ma Jun 2009

A Tale Of Two Streets: Incorporating Grouping Structure In High Dimensional Data Mining, Shuangge Ma

Shuangge Ma

No abstract provided.


Regression When The Predictors Are Images, Philip T. Reiss Apr 2009

Regression When The Predictors Are Images, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Catena-Poly[[(Pyridine-Κn)Copper(Ii)]-Μ3-Pyridine-2,6-Dicarboxylato-Κ3o2:O2′,N,O6:O6′], Manoj Trivedi, Daya Shankar Pandey, Nigam P. Rath Mar 2009

Catena-Poly[[(Pyridine-Κn)Copper(Ii)]-Μ3-Pyridine-2,6-Dicarboxylato-Κ3o2:O2′,N,O6:O6′], Manoj Trivedi, Daya Shankar Pandey, Nigam P. Rath

Nigam Rath

In the title compound, [Cu(C7H3NO4)(C5H5N)]n, the CuII atom is in a slightly distorted octa­hedral coordination environment. Each CuII atom is bound to two N atoms and one O atom of the pyridine­dicarboxyl­ate (PDA) ligand in a tridentate manner, one N atom of the pyridine mol­ecule and two bridging carboxyl­ate O atoms of adjacent PDA ligands, leading to a linear one-dimensional chain running along the c axis. These chains are further assembled via weak C-H...O and [pi]-[pi] inter­actions into a three-dimensional supra­molecular network structure. The centroid-centroid distance between the [pi]-[pi] inter­acting pyridine rings is 3.9104 (13) Å. The two N atoms …


Researches On Copper. History & Metallurgy, Fathi Habashi Feb 2009

Researches On Copper. History & Metallurgy, Fathi Habashi

Fathi Habashi

The present volume is a collection of selected papers dealing with the extractive metallurgy of copper published by the author and his coworkers. They are reproduced here in a facsimile edition in 240 pages. In addition ten new chapters were specially written in 150 pages. The book is fully illustrated by many colored pictures, flowsheets, and diagrams. It is hoped that it will be useful for students, engineers, chemists, geologists, and for research workers.


Gold. History, Metallurgy, Culture, Fathi Habashi Feb 2009

Gold. History, Metallurgy, Culture, Fathi Habashi

Fathi Habashi

Gold, the first metal used by man, has a special place among metals. It plays an important role in society and in world economics. It caused unprecedented mass migrations on three continents, and at least one war. It was responsible for creating many large cities, is highly prized, has been the inspiration of numerous myths, was the ultimate goal of alchemists, stored in the vaults of banks, widely on display in oriental bazaars, and is generously used in decorating churches and temples. The present volume is composed of two parts: a collection of selected papers published by the author on …


Surface Reflectance Properties Of Antarctic Moss And Their Relationship To Plant Species, Pigment Composition And Photosynthetic Function, C. E. Lovelock, Sharon A. Robinson Feb 2009

Surface Reflectance Properties Of Antarctic Moss And Their Relationship To Plant Species, Pigment Composition And Photosynthetic Function, C. E. Lovelock, Sharon A. Robinson

Sharon Robinson

We investigated how surface reflectance properties and pigment concentrations of Antarctic moss varied over species, sites, microtopography, and with water content. We found that species had significantly different surface reflectance properties, particularly in the region of the red edge (approximately 700 nm), but this did not correlate strongly with pigment concentrations. Surface reflectance of moss also varied in the visible region and in the characteristics of the red edge over different sites. Reflectance parameters, such as the Photochemical Reflectance Index (PRI) and Cold Hard Band (CBH) were useful discriminators of site, microtopographic position and water content. The PRI was correlated …


Understanding The Tolerance Of Antarctic Mosses To Climate Change, Sharon A. Robinson, L J. Clarke Feb 2009

Understanding The Tolerance Of Antarctic Mosses To Climate Change, Sharon A. Robinson, L J. Clarke

Sharon Robinson

Climate change is expected to affect the high latitudes first and most severely, rendering Antarctica one of the most significant baseline environments for the study of global climate change. Despite this, there have been few long-term studies of the response of Antarctic vegetation to climate change. The Windmill Islands region supports some of the most extensive and best developed vegetation on continental Antarctica, with lush, green mossbeds along many of the lakes and melt streams close to Casey station. Over the past 12 years my University of Wollongong colleagues and I have studied the mosses of this region to better …


Synchronicity Of Thermogenic Activity, Alternative Pathway Respiratory Flux, Aox Protein Content, And Carbohydrates In Receptacle Tissues Of Sacred Lotus During Floral Development, Nicole M. Grant, Rebecca E. Miller, Jennifer R. Watling, Sharon A. Robinson Feb 2009

Synchronicity Of Thermogenic Activity, Alternative Pathway Respiratory Flux, Aox Protein Content, And Carbohydrates In Receptacle Tissues Of Sacred Lotus During Floral Development, Nicole M. Grant, Rebecca E. Miller, Jennifer R. Watling, Sharon A. Robinson

Sharon Robinson

The relationships between heat production, alternative oxidase (AOX) pathway flux, AOX protein, and carbohydrates during floral development in Nelumbo nucifera (Gaertn.) were investigated. Three distinct physiological phases were identified: pre-thermogenic, thermogenic, and post-thermogenic. The shift to thermogenic activity was associated with a rapid, 10-fold increase in AOX protein. Similarly, a rapid decrease in AOX protein occurred post-thermogenesis. This synchronicity between AOX protein and thermogenic activity contrasts with other thermogenic plants where AOX protein increases some days prior to heating. AOX protein in thermogenic receptacles was significantly higher than in post-thermogenic and leaf tissues. Stable oxygen isotope measurements confirmed that the …


Uv-B Screening Potential Is Higher In Two Cosmopolitan Moss Species Than In A Co-Occurring Antarctic Endemic Moss – Implications Of Continuing Ozone Depletion, J. L. Dunn, Sharon A. Robinson Feb 2009

Uv-B Screening Potential Is Higher In Two Cosmopolitan Moss Species Than In A Co-Occurring Antarctic Endemic Moss – Implications Of Continuing Ozone Depletion, J. L. Dunn, Sharon A. Robinson

Sharon Robinson

Concentrations of UV-B absorbing pigments and anthocyanins were measured in three moss species, over a summer growing season in Antarctica. Pigment concentrations were compared with a range of climatic variables to determine if there was evidence that pigments were induced by UV-B radiation, or other environmental parameters, and secondly if there were differences between species in their pigment responses. Significant seasonal differences in the potential UV-B screening pigments were found, with the two cosmopolitan species Bryum pseudotriquetrum and Ceratodon purpureus appearing better protected from the potentially damaging effects of ozone depletion than the Antarctic endemic Schistidium antarctici. Bryum pseudotriquetrum accumulated …


Contribution Of The Alternative Pathway To Respiration During Thermogenesis In Flowers Of The Sacred Lotus, Jennifer R. Watling, Sharon A. Robinson, Roger S. Seymour Feb 2009

Contribution Of The Alternative Pathway To Respiration During Thermogenesis In Flowers Of The Sacred Lotus, Jennifer R. Watling, Sharon A. Robinson, Roger S. Seymour

Sharon Robinson

We report results from in vivo measurements, using oxygen isotope discrimination techniques, of fluxes through the alternative and cytochrome respiratory pathways in thermogenic plant tissue, the floral receptacle of the sacred lotus (Nelumbo nucifera). Fluxes through both pathways were measured in thermoregulating flowers undergoing varying degrees of thermogenesis in response to ambient temperature. Significant increases in alternative pathway flux were found in lotus receptacles with temperatures 16°C to 20°C above ambient, but not in those with lesser amounts of heating. Alternative pathway flux in the hottest receptacles was 75% of the total respiratory flux. In contrast, fluxes through the cytochrome …


Modeling The Status And Threats To The Philippine Eagle In The Eastern Mindanao Biodiversity Corridor, Vicente Calag, Sean Fitzgerald, James Hafner, Jayson Ibanez, Alicia Johnson, Don Sluter Dec 2008

Modeling The Status And Threats To The Philippine Eagle In The Eastern Mindanao Biodiversity Corridor, Vicente Calag, Sean Fitzgerald, James Hafner, Jayson Ibanez, Alicia Johnson, Don Sluter

James A Hafner

The Philippines is among the most endemic-rich areas for all global biodiversity hotspots. Conserving that biodiversity presents multi-scaled challenges including the critical need for habitat and species level documentation as a basis for identifying conservation targets. This paper contributes to that need by describing the use of A Composite Bio-geographic Analysis (CBA) model to model the dynamics and inter-relationships between species distribution, nest, habitat and land use change, population distribution and access to the PA and to synthesize and evaluate data on the status and threats to the Philippine Eagle Pithecophaga jefferyi in the Mt. Hamiguitan Protected Area, one of …


Brain Activation For Reading And Listening Comprehension: An Fmri Study Of Modality Effects And Individual Differences In Language Comprehension., Augusto Buchweitz, Robert Mason, Tomitch Leda, Marcel Just Dec 2008

Brain Activation For Reading And Listening Comprehension: An Fmri Study Of Modality Effects And Individual Differences In Language Comprehension., Augusto Buchweitz, Robert Mason, Tomitch Leda, Marcel Just

Marcel Adam Just

No abstract provided.


Altering Cortical Connectivity: Remediation-Induced Changes In The White Matter Of Poor Readers, Timothy Keller, Marcel Just Dec 2008

Altering Cortical Connectivity: Remediation-Induced Changes In The White Matter Of Poor Readers, Timothy Keller, Marcel Just

Marcel Adam Just

No abstract provided.


Japanese And English Sentence Reading Comprehension And Writing Systems: An Fmri Study Of First And Second Language Effects On Brain Activation, Augusto Buchweitz, Robert A. Mason, Akiko Hasegawa, Marcel Adam Just Dec 2008

Japanese And English Sentence Reading Comprehension And Writing Systems: An Fmri Study Of First And Second Language Effects On Brain Activation, Augusto Buchweitz, Robert A. Mason, Akiko Hasegawa, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Atypical Frontal-Posterior Synchronization Of Theory Of Mind Regions In Autism During Mental State Attribution, Rajesh K. Kana, Timothy A. Keller, Vladimir L. Cherkassky, Nancy J. Minshew, Marcel Adam Just Dec 2008

Atypical Frontal-Posterior Synchronization Of Theory Of Mind Regions In Autism During Mental State Attribution, Rajesh K. Kana, Timothy A. Keller, Vladimir L. Cherkassky, Nancy J. Minshew, Marcel Adam Just

Marcel Adam Just

No abstract provided.


The Role Of The Theory-Of-Mind Cortical Network In The Comprehension Of Narratives, Robert Mason, Marcel Just Dec 2008

The Role Of The Theory-Of-Mind Cortical Network In The Comprehension Of Narratives, Robert Mason, Marcel Just

Marcel Adam Just

No abstract provided.


Fundamentals For Using Geographic Information Science To Measure The Effectiveness Of Land Conservation Projects, Robert G. Pontius Jr., Shaily Menon, Joseph Duncan, Shalini Gupta Dec 2008

Fundamentals For Using Geographic Information Science To Measure The Effectiveness Of Land Conservation Projects, Robert G. Pontius Jr., Shaily Menon, Joseph Duncan, Shalini Gupta

Shaily Menon

Some humans spend a tremendous amount of effort to change landscapes from a “natural” state to a “developed” state for a variety of desirable economic uses, such as urban, agriculture, transportation, and mining. Others spend a tremendous amount of effort to prevent such development in order to conserve the landscapes for a variety of important environmental uses, such as biodiversity maintenance, carbon storage, water filtration, and landslide prevention. It would be efficient in theory if a society were to focus its development efforts at locations that give the largest economic utility per area developed, and to focus its conservation efforts …