bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of ontogenetic changes in gene expression in the fathead minnow (Pimephales promelas)
Authors: Johns Sonia M. , Kane Michael D. , Denslow Nancy D. , Watanabe Karen H. , Orlando Edward F. , Villeneuve Dan L. , Ankley Gerald T. , Sepúlveda Maria S. 
Published: March 2009

AbstractRecently, researchers have begun looking at changes in gene expression in the fathead minnow (Pimephales promelas) after contaminant exposure as a way to develop biomarkers of exposure and effects. However, the bulk of this research has been conducted on adults, with few studies focusing on early life stages. Expression of selected genes important in growth, development, and reproduction in teleosts was quantified by quantitative polymerase chain reaction during different developmental time periods (from 0 to 28 d postfertilization [dpf]). Over the developmental period studied, there was a significant up-regulation of growth hormone mRNA and no significant changes in the expression of insulin-like growth factor 1. Thyroid hormone receptors A and B were detected in 4 dpf embryos and their expression stayed relatively constant. The variation in cytochrome P45019A mRNA expression was large during the first week of development, returning to 0 dpf expression levels thereafter. Estrogen receptor 2B was up-regulated during the first three weeks postfertilization, returning to prehatch values by 28 dpf. Expression of hydroxysteroid dehydrogenase 3B and steroidogenic acute regulatory protein increased after the third or fourth week postfertilization, respectively. Vitellogenin exhibited a large degree of variation within time points, especially after day 15, and a significant up-regulation for this gene was observed at 7 and 10 dpf. Knowledge of the normal changes in gene expression during embryo and larval development will allow for better experimental design and selection of suitable biomarkers when testing the potential toxicological effects of contaminants in this model fish species.
Trends in Perinatal and Infant Health Disparities Between Rural American Indians and Alaska Natives and Rural Whites
Authors: Baldwin Laura-Mae , Grossman David C. , Murowchick Elise , Larson Eric H. , Hollow Walter B. , Sugarman Jonathan R. , Freeman William L. , Hart L. Gary 
Published: March 2009

Objectives. We examined disparities in perinatal care, birth outcomes, and infant health between rural American Indian and Alaska Native (AIAN) persons and rural Whites over time.Methods. We compared perinatal and infant health measures for 217 064 rural AIAN births and 5 032 533 rural non-Hispanic White births.Results. Among American Indians and Alaska Natives, unadjusted rates of inadequate prenatal care (1985–1987, 36.3%; 1995–1997, 26.3%) and postneonatal death (1985–1987, 7.1 per 1000; 1995–1997, 4.8 per 1000) improved significantly. However, disparities between American Indians and Alaska Natives and Whites in adjusted odds ratios (AORs) of postneonatal death (1985–1987, AOR = 1.55; 95% confidence interval [CI] = 1.41, 1.71; 1995–1997, AOR = 1.46; 95% CI = 1.31, 1.64) and adjusted risk ratios (ARRs) of inadequate prenatal care (1985–1987, ARR = 1.67; 95% CI = 1.65, 1.69; 1995–1997, ARR = 1.84; 95% CI = 1.81, 1.87) persisted.Conclusions. Despite significant decreases in inadequate prenatal care and postneonatal death among American Indians and Alaska Natives, additional measures are needed to close persistent health gaps for this group.
On some infinite dimensional linear groups
Authors: Kurdachenko Leonid , Sadovnichenko Alexey , Subbotin Igor 
Published: March 2009

Abstract
Let F be a field, A be a vector space over F, and GL(F,A) the group of all automorphisms of the vector space A. A subspace B of A is called nearly G-invariant, if dimF(BFG/B) is finite. A subspace B is called almost G-invariant, if dimF(B/CoreG(B)) is finite. In the present article we begin the study of subgroups G of GL(F,A) such that every subspace of A is either nearly G-invariant or almost G-invariant. More precisely, we consider the case when G is a periodic p′-group where p = charF.
Hydrogen adsorption on Pd(133) surface
Authors: Tomaszewska Agnieszka , StÄ™pieÅ„ ZdzisÅ‚aw 
Published: March 2009

Abstract
An approach based on measurements of the total energy distribution (TED) of field emitted electrons is used in order to examine properties of the Pd(133) from the aspect of hydrogen adsorption. The most favourable sites offered to a hydrogen atom to be adsorbed are indicated and an attempt to ascribe the peaks of the enhancement factor R in the TED spectrum to the specific adsorption sites is made.
The structure of average turbulent flow field
Authors: Heinloo Jaak 
Published: March 2009

Abstract
A mathematical formalism to reflect the turbulent hierarchic eddy structure in an average turbulence description is discussed. The formalism is founded on simultaneous application of turbulent flow field splitting procedures by the motion variability and by the motion order explained in the paper. It is shown that this formalism permits the outlining of different types of cascading processes in turbulent media within the turbulence average description.
Crystalline silicon solar cells with high resistivity emitter
Authors: Panek P. , Drabczyk K. , Zięba P. 
Published: March 2009

AbstractThe paper presents a part of research targeted at the modification of crystalline silicon solar cell production using screen-printing technology. The proposed process is based on diffusion from POCl3 resulting in emitter with a sheet resistance on the level of 70 Ω/□ and then, shaped by high temperature passivation treatment. The study was focused on a shallow emitter of high resistivity and on its influence on output electrical parameters of a solar cell. Secondary ion mass spectrometry (SIMS) has been employed for appropriate distinguishing the total donor doped profile. The solar cell parameters were characterized by current-voltage characteristics and spectral response (SR) methods. Some aspects playing a role in suitable manufacturing process were discussed. The situation in a photovoltaic industry with emphasis on silicon supply and current prices of solar cells, modules and photovoltaic (PV) systems are described. The economic and quantitative estimation of the PV world market is shortly discussed.
Design of the Dynamic Positioning System for the Drillship Glomar C. R. Luigs
Authors: Virk G.S. , Chiu Hin , Deter D.R. , van der Stoep C. 
Published: March 2009

Abstract
Glomar C. R. Luigs is a state of the art, ultra-deep water, drillship, equipped with Nautronix ASK 5003 dynamic positioning controller, which controlsthe thrust vector from six (6), 5 MW each, azimuthing thrusters to providesuperb stationkeeping capability. The system meets the ABS class requirementsfor DPS-3. The basic elements of a Dynamic Positioning System (DPS) are:Sensor System,Controller,Thruster System,Power System.
Theemphasis of this paper is on the thruster system. The thruster design has beenoptimized to satisfy the conflicting requirements for stationkeeping andpropulsion.
The paper briefly discusses the preliminary analytical studies to estimatethe DP power requirements and size the thruster system to satisfy thestationkeeping requirement for the specified metocean design criteria. This wasfollowed by a full complement of scale model tests for stationkeeping, seakeeping, propulsion, and wind tunnel tests. The paper discusses how theresults of the model tests were utilized to calibrate the analytical predictionmodel in order to predict the expected prototype performance.
The paper discusses the correction factors to the open water thrusterperformance for hull-thruster, thruster-thruster, and thruster-appendagesinteractions, in order to predict the inservice performance of the thrusters inthe stationkeeping mode. The forbidden zones for thruster operation weredeveloped from these interaction studies in order to provide input to the DPcontroller for optimum thruster performance. The influence on thrust of thecross-coupled side forces due an oblique inflow will also be discussed. Thepaper attempts to present a unified methodology for the thruster design inorder to achieve optimum stationkeeping and propulsion performance.

Introduction
Global Marine pioneered drilling from a floater, particularly a drillship. Adrillship's mobility, payload capacity, safety record, and ability to head intothe weather, gave it a tremendous advantage to operate in almost allgeographical regions of the world, albeit seasonal operation in harsh weatherareas. After the advent of jackup and semisubmersible drilling units, the useof a drillship declined in comparison, as the former's unique design featuresfound an optimum application for specific geographical areas.
Start-Up and Shut-In Issues for Subsea Production of High Paraffinic Crudes
Authors: Thomason William H. 
Published: March 2009

Abstract
A major flow assurance challenge is the production and transport of highparaffinic crudes in offshore fields where subsea flow lines and exportpipelines are involved. The challenge is particularly great when the sea watertemperature is lower than the pour point of the crude being produced andtransported. This paper describes flow assurance issues (with emphasis onstart-up and shut-in) for handling subsea production and transportation ofparaffinic crudes. Physical performance data for crudes are needed toplan/design for start-up, shut-in, and steady state operations. Theseperformance data include cloud point, pour point, gel strength, and viscosityas a function of temperature, shear rate, and dissolved gas. Examples of thesedata for high paraffinic crudes and how they were used to design productionsystems and develop operating guidelines for start-ups and shut-ins arepresented. Examples of transient flow computations for planned productionsystems are also presented. The principle focus of the examples are for subseasystems in which the seawater temperature is below the pour point temperatureof the produced crude.

Introduction
In its effort to find reliable and economic sources of oil, the offshore oilindustry continues to encounter and successfully handle more and morechallenging production environments. One of these is the production of highparaffinic crudes in offshore fields where subsea flow lines and exportpipelines are involved. The challenge is particularly great when the sea watertemperature is lower than the pour point of the crude being produced andtransported. Provisions for handling flow assurance issues such as crudegelling, wax deposition control, and high viscosities must be incorporated inthe system design and operation. Since many of the possible provisions forhandling flow assurance involve significant cost, their need and potentialeffectiveness must be properly evaluated, and their application selectedwisely.
The paper discusses a process for planning and designing systems for subseatransport of high paraffinic crudes. The process involves data collection toinclude measurement of the crude properties, assessment of the thermalconditions that the crude will experience, and assessment of the impact of gas, water, and terrain. With these crude property data and an estimate of the rangeof environmental conditions, one can then develop a plan to best handle theproduced crude and enable recovery from shut-ins and low flow rateconditions.
Glycoconjugates: Structure and Biosynthesis
Authors: Williams Spencer J 
Published: March 2009

AbstractCarbohydrates are frequently found attached to lipids (e.g., glycoglycerolipids and glycosphingolipids), proteins (glycoproteins and proteoglycans), or in some cases, both (glycosylphosphatidylinositol‐anchored proteins). Three main types of protein modification are found in vertebrates:N‐linked glycosylation,O‐linked glycosylation, and the attachment of glycosylphosphatidylinositol anchors; also, a fourth rarer type,C‐mannosylation, is found. In the main types, the biosynthesis of glycoconjugates occurs in two specialized, membranous biosynthetic compartments within the cell: the endoplasmic reticulum and the Golgi apparatus. Degradation of glycoconjugates occurs in another specialized membranous digestive compartment: the lysosome. The two major groups of enzymes that mediate the biosynthesis and degradation of glycoconjugates are glycosyltransferases and glycoside hydrolases. This article will review the classification and mechanisms of glycosyltransferases and glycoside hydrolases and give an overview of their roles in the biosynthesis and degradation of vertebrate glycoconjugates: glycolipids, glycoproteins, proteoglycans, and glycosylphosphatidylinositol anchors.
Ion Channels
Authors: Andersen Olaf S. , Ingólfsson Helgi I. , Lundbæk Jens A. 
Published: March 2009

Abstract
Ion channels catalyze the transmembrane movement of small inorganic ions across biological membranes. They do so by forming continuous, hydrophilic pores through which ions can cross the barrier imposed by the lipid bilayer hydrophobic core. Ion channels serve many functions: they underlie the changes in membrane potential that control many cell functions, including the propagated electrical signaling (the action potentials) in electrically excitable cells; they allow for the bulk movement of ions across cell membranes. In this article we summarize key features of ion channels, with special emphasis on the channels in the plasma membrane—their structure and catalytic power, the generation of membrane potential changes, the regulation (or gating) that underlies normal channel function, and how channel function can be modulated by small molecules.
Proteasome, Chemistry of
Authors: Osmulski Pawel A , Tokmina‐Lukaszewska Monika , Endel Lydia , Sosnowska Renata , Gaczynska Maria 
Published: March 2009

AbstractThe proteasome is a multisubunit and multifunctional intracellular protease widespread from Archaebacteria to Eukaryota. In the latter, the proteasome is an essential enzyme and a convergence point of the ubiquitin‐proteasome pathway (UPP), which provides the major venue for intracellular controlled proteolysis. In the most basic scenario, proteins are tagged by multiple copies of ubiquitin, as such recognized by the proteasome, then deubiquitinated, unfolded, and degraded to short peptides. Following up the evolutionary ladder, the proteasome assemblies gain complexity and diversity. Nevertheless, all of them share the essential catalytic core: a compartmentalized protease exhibiting a common architecture and catalytic mechanism. The core is a tube‐shaped particle built from four stacked heptameric rings with active sites concealed inside the two internal rings and self‐activated during its assembly. Hydroxyl and amino groups of Thr1 forming a catalytic dyad are employed to break peptide bonds using the N‐terminal nucleophile‐type mechanism. The proteasomes of higher Eukaryota are equipped with six active sites of specificities imposed by three distinct binding pockets. Binding of additional protein regulators to the core extends its capabilities into new functions, for example, processing of polyubiquitinated substrates. In the serendipitous twist, the proteasome recently became an attractive target for anti‐cancer and anti‐inflammatory drugs, which propelled studies on the mechanism of actions of the enzyme.
Transcription: Initiation
Authors: Martin Craig T. , Mironova Olga S. 
Published: March 2009

AbstractInitiation of transcription is a complex process, requiring melting of the DNA duplex at a sequence‐defined location,de novosynthesis of an initial dinucleotide, polymerization/growth from that dinucleotide to a larger oligonucleotide in an extended RNA‐DNA hybrid, displacement and threading of the 5′ end of the RNA into an exit channel, and release of the initial promoter contacts. These events are necessarily driven energetically by growth of the RNA‐DNA hybrid. It has long been expected and is now becoming structurally clear that stress inherent in this transformation leads to instability during this phase and is a source of the abortive release of short RNA products that is characteristic of RNA polymerases. That apparently unrelated single and multisubunit RNA polymerases share extensive mechanistic (but not structural) homology, likely reflects the demands of the process.
DNA‐Conjugated Organic Chromophores inDNAStacking Interactions
Authors: Filichev Vyacheslav V. , Pedersen Erik B. 
Published: March 2009

AbstractSince the discovery of the intercalation of acridine derivatives into DNA (1961), chemists have synthesized many intercalators tethered to DNA. Advances in the chemical synthesis of modified nucleosides along with progress in oligonucleotide synthesis have made it possible to introduce organic chromophores in any desired position of the sequence. As an outcome of such fascinating research, we gained a deeper knowledge and understanding of nucleic acid structures, which is pivotal for future progress within nucleic acid technology and for development of novel approaches in drug design. The current review presents those efforts in the design of intercalators/organic chromophores as oligonucleotide conjugates that form a foundation for the generation of novel nucleic acid architectures.
Small Molecules that Target Schizophrenia
Authors: Martenyi, MD, PhD Ferenc 
Published: March 2009

AbstractSince the discovery of chlorpromazine in 1953, the number of antipsychotic medications has increased tremendously. Most of these drugs affect the dopaminergic neurotransmission (primarily blocking dopamine D2receptors). Antipsychotics registered until 2008 could be classified into 3 groups based on receptor occupancy profile rather than using their chemical structure. Conventional (or first‐generation antipsychotics, like haloperidol and fluphenazine) with a predominant D2receptor affinity have benefits in the treatment of delusions and hallucinations (positive symptoms of schizophrenia), which are parallel with a characteristic side‐effect profile of extrapyramidal symptoms (EPS) and prolactin elevation. Atypical antipsychotics—which are characterized by a higher antagonist affinity to serotonin (5‐hydroxytryptamine, 5HT) 5HT2receptors than to dopamine D2receptors—are generally thought to be effective in alleviation of negative symptoms (such as anhedonia, and lack of motivation) beyond the positive symptoms domain of schizophrenia, with a reduced EPS burden (such as clozapine, olanzapine, risperidone). A third group of novel antipsychotics has a partial dopamine agonist profile (aripiprazole), with a lack of or minimal EPS. The nondopaminergicN‐methyl‐D‐aspartate (NMDA) antagonist model of schizophrenia raised new gulatamatergic targets for treatment. NMDA antagonists ketamine and phencyclidine produce wide range of symptoms characteristic for schizophrenia, such as positive and negative symptoms as well as cognitive impairment. Compounds that blunt gulatamatergic activity (for example lamotrigine) or NMDA receptor glycine site allosteric agonists have both showed improvement of schizophrenic symptoms in combination with antipscychotics. The first compound that produced improvement in monotherapy for the treatment of schizophrenia is LY214023, which is a metabotropic Glutamate 2/3 (mGlu2/3) receptor agonist. This article reviews neurobiological background of treatments and clinical experiences proven in controlled clinical trials.
Pathogen‐Host Interactions: Chemical Biology Approach
Authors: Hett Erik C. , Hung Deborah T. 
Published: March 2009

AbstractMicrobes are continuously coevolving with their eukaryotic hosts. This process can result in a stable relationship of mutual benefit or an unstable relationship with pathologic consequences to the host. The latter relationship, which is known as the pathogen–host interaction, represents an ideal research area in which chemical biology can be applied to study the disease‐causing mechanisms of many bacterial pathogens. Chemical interference of pathogenicity can target specific virulence mechanisms of the pathogen or functions of the host organism involved in generating pathology. Small‐molecule modulators and their targets are extremely useful tools for studying specific mechanisms of disease and can help reveal novel cell biological processes. Promising compounds could also lead to the generation of novel paradigms for therapeutics. Here, we present examples of specific pathogen–host interactions and the chemical biological approaches that can be taken to both study and fight such pathogens.
Collaborative Intelligence = Respect
Authors: Kaseman Keith 
Published: March 2009

AbstractCultural projects today are often unprecedented in their complexity, scale and collaborative effort. Keith Kaseman, partner of Kaseman Beckman Advanced Strategies (KBAS), describes how building information modelling (BIM) enabled the realisation of the Pentagon Memorial in Arlington, Virginia. Twenty‐eight contractors and consultants were brought on board in the design and delivery of the monument's 184 ‘memorial units’, which collectively commemorate the individual lives lost at the Pentagon on 11 September 2001.
Electrically Conductive Thin Films Prepared from Layer‐by‐Layer Assembly of Graphite Platelets
Authors: Alazemi Mubarak , Dutta Indrajit , Wang Feng , Blunk Richard H. , Angelopoulos Anastasios P. 
Published: March 2009

AbstractLayer‐by‐layer (LBL) assembly of carbon nanoparticles for low electrical contact resistance thin film applications is demonstrated. The nanoparticles consist of irregularly shaped graphite platelets, with acrylamide/ββ‐methacryl‐oxyethyl‐trimethyl‐ammonium copolymer as the cationic binder. Nanoparticle zeta (ζζ) potential and thereby electrostatic interactions are varied by altering the pH of graphite suspension as well as that of the binder suspension. Film thickness as a function of zeta potential, immersion time, and the number of layers deposited is obtained using Monte Carlo simulation of the energy dispersive spectroscopy measurements. Multilayer film surface morphology is visualized via field‐emission scanning electron microscopy and atomic‐force microscopy. Thin film electrical properties are characterized using electrical contact resistance measurements. Graphite nanoparticles are found to self‐assemble onto gold substrates through two distinct yet overlapping mechanisms. The first mechanism is characterized by logarithmic carbon uptake with respect to the number of deposition cycles and slow clustering of nanoparticles on the gold surface. The second mechanism results from more rapid LBL nanoparticle assembly and is characterized by linear weight uptake with respect to the number of deposition cycles and a constant bilayer thickness of 15 to 21 nm. Thin‐film electrical contact resistance is found to be proportional to the thickness after equilibration of the bilayer structure. Measured values range from 1.6 mΩ cm−2 at 173 nm to 3.5 mΩ cm−2 at 276 nm. Coating volume resistivity is reduced when electrostatic interactions are enhanced during LBL assembly.
Self‐Assembly of a Four‐Helix Bundle on a DNA Quadruplex
Authors: Rosenzweig Brooke A. , Hamilton Andrew D. 
Published: March 2009

AbstractCome together: A novel method for assembling monomers and controlling structure of a de novo helix bundle protein is described. A guanine (G)‐rich oligodeoxynucleotide scaffold forms a hydrogen‐bonded DNA quadruplex in the presence of potassium counterions, thereby inducing a helical structure and fourfold stoichiometry in conjugated, amphiphilic peptide sequences. The DNA scaffold shows potential for rapidly assembling designed proteins.magnified image
Sonochemical Synthesis of Highly Luminescent Zinc Oxide Nanoparticles Doped with Magnesium(II)
Authors: Xiong Huan‐Ming , Shchukin Dmitry G. , Möhwald Helmuth , Xu Yang , Xia Yong‐Yao 
Published: March 2009

AbstractA bright idea: Mg/ZnO nanoparticles that exhibit bright, stable photoluminescence both in colloidal dispersions and in the solid state are formed by doping MgII ions into ZnO nanoparticles by sonochemical synthesis. The changes in their band gaps and luminescence properties rely on the defect concentrations inside the ZnO nanoparticles; these concentrations are determined by the Mg/Zn molar ratios (see picture).magnified image