bluuebunny/crossref_metadata_2025 huggingface dataset:
Pedestrian Simulation Modeling Study for World Trade Center Memorial
Authors: Monteleone Michael F. , Veraart Niek , Chough Suany , Aviles Wendy
Published: December 2008

The development of the World Trade Center (WTC) Memorial site is one of the most important design projects in U.S. history. Since the site is so venerated, the experience of individuals visiting the site has been an extremely important issue to the designers and planners. As a result, it was essential that the site provide a peaceful, nonstressful environment to the thousands of visitors who are expected on a daily basis. As part of the design process, the Lower Manhattan Development Corporation and the National September 11 Memorial and Museum at the World Trade Center began a joint effort in August 2005 to study the movement of pedestrians on the memorial site. It is anticipated that a large number of visitors, employees, and commuters will traverse the site throughout the day. A detailed description of the methodology used to analyze the projected pedestrian activity on the WTC site, including the two-dimensional real-time software used to provide a graphical representation of people's movements across the site, is provided. In addition, several key issues were examined, including an evaluation of the physical design (queuing, ticketing, landscaping, etc.), visitor experience, operational efficiency, and security and safety concerns through the use of this customized and finely grained procedure. The analysis results have enabled planners, designers, and developers to visualize and measure the functionality of the WTC Memorial site from a pedestrian perspective, including how these pedestrians will affect the entire WTC site.
Walking Speed of Older Pedestrians who use Canes or Walkers for Mobility
Authors: Arango Jorge , Montufar Jeannette
Published: December 2008

Findings are presented of a follow-up study conducted in Winnipeg, Canada, to investigate the walking speed of older pedestrians who use walkers or canes for mobility. The results are from research conducted to understand the differences between the normal and the crossing walking speeds of older pedestrians who use walkers or canes for mobility at signalized intersections. This walking speed is also compared with that of older pedestrians who ambulate without assistive devices. For the purposes of this research, normal walking speed is the speed at which pedestrians walk without needing to cross any intersection, and crossing walking speed is that at which pedestrians walk when crossing a signalized intersection. The research found that in all cases the normal speed is lower than the crossing walking speed for older pedestrians with or without assistive devices. There are no seasonal differences in the normal walking speed of older pedestrians with walkers or canes. However, the crossing walking speed is higher in winter than in summer. Regarding gender issues, older men walk faster than older women when assistive devices are not used. However, there are no gender differences in walking speed when pedestrians use walkers or canes for mobility. Although this research shows that using the current walking-speed assumption of 1.2 m/s (4.0 ft/s), as recommended in the U.S. Manual on Uniform Traffic Control Devices, almost all older pedestrians needing walkers or canes for mobility would be excluded in the design process, it also shows other information that would be valuable for improved urban planning, transit operations, and other transportation engineering applications.
Marked-Crosswalk Dilemma
Authors: Mitman Meghan Fehlig , Ragland David R. , Zegeer Charles V.
Published: December 2008

Primarily in response to several landmark safety studies, and as an official or unofficial policy, many agencies across the United States have elected to remove marked crosswalks at uncontrolled intersections or have shown resistance to installing them in the first place. This approach results in unacceptable pedestrian mobility restrictions, yet such restrictions are often not considered in policy making. As such, there is a need for roadway system owners to develop strategic safety guidelines to address the marked-crosswalk dilemma. Since 2005, the Traffic Safety Center at the University of California, Berkeley, in a study funded by the California Department of Transportation, has focused on developing a better understanding of driver and pedestrian behavior and safety in both marked and unmarked crosswalks in an effort to recommend more informed crosswalk policies. The study was designed to fill key gaps in the literature by analyzing pedestrian and driver behavior and knowledge of right-of-way laws regarding marked and unmarked crosswalks. The study also focused on driver and pedestrian behavior in multiple-threat scenarios, the most common type of pedestrian collisions at uncontrolled intersections. Results are summarized from field observations of driver and pedestrian behavior at marked and unmarked crosswalks on low-speed two-lane and multilane roads. The behavioral observations are interpreted in light of findings reported by Mitman and Ragland from surveys and focus groups regarding driver and pedestrian knowledge of right-of-way laws. The discussion concludes with recommendations for a comprehensive crosswalk safety policy to strategically address crash risk at uncontrolled crosswalks.
Accessible Pedestrian Signals at Complex Intersections
Authors: Scott Alan C. , Barlow Janet M. , Bentzen Billie Louise , Bond Tamara L. Y. , Gubbe Douglas
Published: December 2008

Pedestrians with vision impairments often have to cross streets at unfamiliar signalized intersections. The results are reported of research on crossings by blind pedestrians at complex intersections before and after the installation of accessible pedestrian signals (APS) and again following the installation of innovative device features. Objective data on measures of street crossing performance by 56 participants were obtained at four intersections, two each in Charlotte, North Carolina, and Portland, Oregon. The analysis includes broad measures of crossing timing, wayfinding, and independence. After APS installation, delay in starting to cross was reduced by approximately 2 s, and there was significant improvement in independently determining a safe time to cross, beginning to cross during the “Walk” signal, and completing crossings before the onset of perpendicular traffic. Some measures of wayfinding and related measures of independence also improved in Portland. Additional device features introduced after the first postinstallation testing session led to additional improvements in wayfinding during a second postinstallation test in Charlotte.
Visibility and Conspicuity of Detectable Warnings for Pedestrians with Visual Impairments
Authors: Jenness James W. , Singer Jeremiah
Published: December 2008

Detectable warnings are standardized tactile walking surfaces located at the end of curb ramps and train platforms to identify the potential hazard. A study was conducted to determine which detectable warning colors and patterns are visually detectable and conspicuous to pedestrians with visual impairments and to provide recommendations related to color, pattern, and contrast of detectable warnings for placement on sidewalks. Fifty individuals with low vision viewed each of 13 detectable warnings individually on four different types of simulated sidewalk. The set of detectable warnings included both solid colors and black-and-white patterns. The outcomes of interest were visual detection distance, participants’ descriptions of detectable warning colors, and participants’ ratings of each detectable warning's conspicuity against a particular simulated sidewalk. Detection distance results indicate that pedestrians with visual impairments were able to see most combinations of detectable warning and sidewalk from 8 ft away, but fewer were able to see them at greater distances. Detectable warnings that were similar in color to the sidewalk were seen by few participants, indicating that visual cues provided by the truncated-dome texture itself are not sufficient to ensure visual detection. The luminance contrast between the detectable warning and the sidewalk was an important factor for predicting the likelihood that a detectable warning would be seen. Besides luminance contrast, regression analyses indicated that some other characteristics of detectable warnings were generally associated with high detection rates and high conspicuity ratings, including color (reds and yellows rather than achromatic) and reflectance (lighter colors rather than darker colors). Additional recommendations for detectable warning visual characteristics are provided.
Planning for Enrollment Growth
Authors: Miller Michael A.
Published: December 2008

This paper summarizes the methodology and preliminary results from a nearly 2-year study for the Wake County Public Schools System in North Carolina. The size and complexity of this system have provided the opportunity for the Operations Research and Education Laboratory to expand the successful Integrated Planning for School and Community program to encompass a projected enrollment of more than 250,000 students in 2025 and a diverse network of municipality and county land use plans. The goals of this project are to provide flexible, data-driven decision science tools for the location of future school sites and attendance boundaries and to cultivate an environment among Wake County planners and school administration that will foster effective communication of common goals.
Children's Biking for Nonschool Purposes
Authors: Tal Gil , Handy Susan
Published: December 2008

In recent years, transportation planning has devoted new attention to the goal of increasing the nonmotorized trips of children and adults, both as a means of increasing physical activity and as a means of reducing motorized trips. For children, much discussion has focused on the journey to school, with little attention to nonschool trips. In this study, patterns of travel of both children and their parents to youth soccer games in Davis, California, are examined. The study aims to identify factors influencing mode choice among children and parents to soccer games for the Davis American Youth Soccer Organization. Data come from a survey of 1,084 parents accompanying their children to Saturday soccer games. Over three-quarters of players and their parents drove to the game on the day of the survey, with fewer than 20% biking. Multivariate models show that distance to games is a significant deterrent to bicycling or walking to them, while players who bike to school and whose parents regularly bicycle are significantly more likely to bicycle to games.
Novel Strategies to Improve the Anticancer Action of 5-Fluorouracil by Using Drug Delivery Systems
Authors: Arias José L.
Published: December 2008

Because of the fundamental importance of new therapeutic routes for cancer treatment, a number of systems based on colloidal particles as vehicles for the delivery of the anticancer drug 5-fluorouracil have been devised. The target is always to provide the proper dose of the antitumor agent only at the desired locus of action, thus reducing the unwanted side effects. In this review, the main strategies and the more significant results in the development of 5-fluorouracil carriers for cancer treatment are discussed.
A Preliminary Pharmacokinetic Study of Betulin, the Main Pentacyclic Triterpene from Extract of Outer Bark of Birch (Betulae alba cortex)
Authors: Jäger Sebastian , Laszczyk Melanie N. , Scheffler Armin
Published: December 2008

During the last two decades triterpenes have attracted attention because of their pharmacological potential. Triterpene extract (TE) from outer bark of birch consisting mainly of betulin is able to form an oleogel which was successfully tested in the treatment of actinic keratosis. Some aspects of TE in vitro pharmacology are already known. Now we show preliminary pharmacokinetics of betulin and results of a subchronic toxicity study of TE in rats and dogs. Because of poor aqueous solubility of the TE-triterpenes (< 0.1 μg/mL respectively), for pharmacokinetic studies it was suspended in sesame oil (rats, i.p.) and PEG 400 / 0.9 % NaCl (dogs, s.c.). I.p. administered, betulin, the main component of TE, shows time dependency over a period of 4 h and reaches a dose-independent serum level of 0.13 μg/mL. Dose dependency was observed with s.c. administration. At 300 mg/kg a maximum plasma concentration of 0.33 μg/mL betulin was detected after 28 daily applications. The subchronic toxicity study showed no toxicity of TE in rats (i.p.) and dogs (s.c.). In conclusion, triterpene extract from birch bark is safe, its betulin is bioavailable and in addition to published triterpene biological activities TE provides high potential for further pharmaceutical and pharmacological research.
Conformational Mobility of GOx Coenzyme Complex on Single-Wall Carbon Nanotubes
Authors: Liu Feng , Ye Xue-song , Wu Tao , Wang Chang-Tao , Shen Jia-wei , Kang Yu
Published: December 2008

A critical issue in bioelectrochemical applications that use electrodes modified by Single Wall Carbon Nanotubes (SWCNTs) is to ensure high activity of the catalytic site of an immobilized enzyme protein interacting with nanomaterials. Since Flavin Adenine Dinucleotide (FAD), a coenzyme of glucose oxidase (GOx), is the active center of the catalytic site, conformation of which could determine the activity of enzyme, it is important to understand the dynamic mechanism of its conformational mobility while GOx is adsorbed on SWCNTs with multiple orientations. However, this dynamic mechanism still remains unclear at the atomic level due to the coenzyme being embedded in the apo-GOx and the limitations of appropriate experimental methods. In this study, a molecular dynamics (MD) simulation was performed to investigate the conformational mobility mechanism of the coenzyme. The trajectory and the interaction energy clearly indicate that the adsorption of GOx onto SWCNTs plays an important role in the conformational mobility of the coenzyme, and its mobility is greatly affected by the distribution of water molecules due to it being hydrophobic.
Animal Models of Collagen‐Induced Arthritis
Authors: Wagner Stéphanie , Bindler Julien , Andriambeloson Emile
Published: December 2008

Collagen‐induced arthritis in rats is associated with inflammatory polyarthritis, sharing clinical and pathological features with those of human rheumatoid arthritis (RA). Described in this unit is a protocol for consistently inducing arthritis in female Lewis rats by immunizing them with bovine type II collagen (CII) emulsified in complete Freund's adjuvant. This model is of value not only in defining the underlying pathogenesis of RA, but also as a tool for evaluating pharmacological strategies for treating this condition. Curr. Protoc. Pharmacol. 43:5.51.1‐5.51.8. © 2008 by John Wiley & Sons, Inc.
In Vitro Assay of Angiogenesis: Inhibition of Capillary Tube Formation
Authors: McGonigle Sharon , Shifrin Victor
Published: December 2008

The growth of new blood vessels, or angiogenesis, is a naturally occurring process in both health and disease states. An area of active research, regulation of angiogenesis, is being studied as an approach for the treatment of cancer and a range of other disorders having vascular proliferation as a component. The process of angiogenesis is very complex and occurs in multiple steps, with a major involvement of endothelial cells. Various in vivo models have been developed to assess inhibitors of angiogenesis. As these are generally technically difficult and labor intensive, with observed effects difficult to quantify, they do not lend themselves to compound screening. Rather they are used for confirmatory studies. In contrast, in vitro assays developed to model various steps in the angiogenesis process are easy to perform and lend themselves to high‐throughput analysis. Described in this unit is an in vitro assay that can be employed to investigate endothelial differentiation inhibitors through assessment of their effects on capillary tube formation by endothelial cells on Matrigel. Curr. Protoc. Pharmacol. 43:12.12.1‐12.12.7. © 2008 by John Wiley & Sons, Inc.
Aquificales
Authors: Bonch‐Osmolovskaya Elizaveta
Published: December 2008

Based on 16S ribosomal
ribonucleic acid
(rRNA) genes sequence comparisons, the order Aquificales represents a very deep phylogenetic branch within the bacterial domain. Some Aquificales relatives have an upper temperature limit of growth at 95°C. Together with members of the order Thermotogales, they represent bacteria with the highest growth temperatures known so far. However, unlike Thermotogales, most of the members of the order Aquificales are aerobic or anaerobic lithoautotrophs, using energy of molecular hydrogen, or of reduced sulfur compounds to support their growth.
Translation Control byRNA
Authors: Goldman Emanuel
Published: December 2008

Translation control by RNA (ribonucleic acid) refers to the process by which protein synthesis is regulated by structural elements in RNA (primary, secondary or tertiary), oftencis‐acting in the messenger RNA encoding the protein being synthesized, and alsotrans‐acting in a number of systems.
Transgenic Animal Models of B‐ and T‐Cell Autoreactivity
Authors: Radic Marko Z
Published: December 2008

Transgenic animals can be made to express self‐reactive antigen receptors by constructing heritable genetic modifications of their germline. The development of transgenic technology has been used to learn about the pathogenic role and regulation of autoreactive B and T lymphocytes. Examples highlighted here include T‐cell receptors that contribute to T‐cell‐mediated diabetes mellitus and B‐cell receptors against facultative or obligate self antigens that are regulated by B‐cell anergy or clonal deletion. An unexpected finding was the discovery of receptor editing in B cells expressing site‐directed, transgenic
antideoxyribonucleic acid
(DNA) B‐cell receptors. In these B cells, the products of further immunoglobulin gene rearrangements displace the autoreactive antigen receptor. Notably, the same anti‐DNA receptor can participate in an autoimmune response, if the immunoglobulin transgene is backcrossed on an autoimmune genetic background. Because the analysis of transgenic antigen receptors has led to many exciting discoveries it is likely that transgenic animals will remain front and centre of immunology research for years to come.
Flooding‐Stress in Plants
Authors: Sachs Martin M
Published: December 2008

Flooding is a stress that crop plants frequently encounter and results in huge economic losses. Studies on the effects of flooding at the molecular level may lead to improvements that will result in flood‐tolerant crop plants.

Key concepts

Flooding leads to a deprivation of oxygen in plants. Many plants respond to oxygen deprivation with adaptations that allow short‐term survival. Some plants show excellent tolerance to anoxia.
Apoptosis: Morphological Criteria and Other Assays
Authors: Gobe Glenda , Harmon Brian
Published: December 2008

Apoptosis is a morphologically and biochemically distinct mode of cell death that uses the cell's own energy and genetic control for death to occur. It is central to many physiological processes such as morphogenesis, homeostasis and differentiation. In disease, apoptosis is responsible for loss of functioning tissue as well as negating and over‐riding cell proliferation in disorders such as neoplasias and cancers.
History of Neuroscience
Authors: Glickstein Mitchell
Published: December 2008

This review traces the history of neuroscience from its origins to recent times. Early physicians recognized that the brain controls sensation and movement, learning and thought, and that communication between the brain and the body is by way of the spinal cord. A fundamental principle of nervous system structure is the neuron doctrine, the idea that brain and spinal cord are made up of individual elements called neurons, which may touch one another but do not fuse. Communication among neurons and activation of muscles is accomplished in most cases by release of a chemical transmitter substance. Understanding of the nature of electrical signalling in the nervous system culminated in the discovery of the ionic basis of the action potential. Early observations of the effect of brain injury on speech and language, sensation and movement revealed that different parts of the brain and spinal cord are specialized for different functions. The development of techniques for single‐cell recording in animals and computer‐based imaging in humans showed that there are multiple cortical areas dedicated to further processing of the sensory message, and control of movement.
Macroecology
Authors: Hawkins Bradford A , Diniz‐Filho José Alexandre Felizola
Published: December 2008

Macroecology is ecology at large spatial scales, focusing on identifying the ecological and evolutionary forces that influence patterns in body size, geographic range size, abundance, diversity and related macroevolutionary trends. The field has traditionally focused on across‐species comparisons, but recent work has begun to analyse macroecological patterns from a geographical perspective. This change makes the links between ecological traits and diversity patterns more explicit and provides a unified approach for understanding a range of large‐scale ecological patterns. Newly developed analytical methods also make it possible to partition geographical patterns into components comprising the species‐level adaptive responses of assemblages to environmental gradients and phylogenetic patterns arising from species turnover. Macroecology is founded on the principle that the study of geographic‐scale species assemblages can conceptually link a number of different biological disciplines.
Parasites and Pathogens: Avoidance
Authors: Thieltges David W , Poulin Robert
Published: December 2008

Parasites and pathogens are usually harmful, and thus hosts have developed numerous pre‐contact measures to avoid infection in the first place. These avoidance measures range from camouflage to a variety of behavioural measures such as movement and fly‐repelling behaviour, habitat choice and migration, selective foraging, group forming and mate choice. In case avoidance fails, a second line of post‐contact defences (e.g. immune system) comes into place which is treated elsewhere and thus only briefly discussed.
Post‐fertilization Reproductive Strategies
Authors: van Dijk René E , Székely Tamás
Published: December 2008

Animals have diverse strategies that improve the success of their offspring after mating (i.e. post‐fertilization reproductive strategies); the most common ones are parental care and offspring provisioning. The type, mode and duration of parental care exhibited by males and females depend on social and nonsocial environment, and on genetic and phylogenetic constraints. We overview five rapidly developing areas of parental care research, and conclude that sexual conflict between parents, social interactions and environmental conditions play important roles in determining post‐fertilization reproductive strategies.
Eye Disorders: Hereditary
Authors: Kaplan Josseline , Rozet Jean‐Michel
Published: December 2008

Hereditary visual deficiencies can result from isolated or associated alterations of any structure of the eye. The identification of the molecular bases of ophthalmologic disorders has revived interest in several conditions forgotten since their original description. Besides, the deciphering of the molecular bases of these conditions has confirmed preexisting hypothesis on their pathophysiology, but for others, the discovery of the disease gene has added further complexity to the disease process. Two contradictory concepts were particularly highlighted. Several phenotypes described as different clinical entities were brought together by the identification of mutations in the same gene, and conversely, some conditions clinically assigned the same name were proved to be genetically and physiopathologically heterogeneous. In both situations, when established, genotype–phenotype correlations made genetic studies easier and allowed having a better knowledge of the prognosis in infants. Finally, progress during the last 20 years, allow today the development of specific therapeutic approaches.
Asthma: Genetics
Authors: Willis‐Owen Saffron AG
Published: December 2008

Asthma is an inflammatory disease of the small airways of the lung. It is strongly influenced by genetic factors. Specific genes have been shown to predispose to the disease by a variety of mechanisms. High‐throughput approaches towards disease gene identification are now being applied, and have already led to important insights into disease aetiology.
Human Gene Nomenclature
Authors: Bruford Elspeth A
Published: December 2008

The HUGO Gene Nomenclature Committee (HGNC) was founded in 1977 to provide a single worldwide authority to assign standardized human gene symbols, and remains one of the essential components of human gene and genome management. The HGNC has two overriding goals: providing a unique nomenclature for every human gene, and ensuring that this information is freely available, widely disseminated and universally recognized. Effective communication between the scientific community, healthcare professionals and the general public is key to our understanding of the wealth of information encoded in the human genome. It is important for future progress in this field that each of these groups refer to the same gene by the same unique name and symbol, in discussions and in publications, and the HGNC aims to facilitate this by assigning such names and symbols to every human gene.

Key concepts

standardization of gene nomenclature; utility of standardized gene names; gene names in genome databases; gene naming guidelines; gene naming across species; gene families.
Sustainable Use of Populations and Overexploitation
Authors: Heino Mikko , Enberg Katja
Published: December 2008

Sustainable use refers to exploiting a resource so that the resource is not depleted or permanently damaged. Sustainability is an internationally accepted minimal goal in managing biological resources. However, many populations are managed under more stringent goals, for example obtaining maximum sustainable biological or economic yield. Overexploitation refers to exploitation that is more intensive than such specific goals. While overexploitation is not sensible from societal point of view, in practice overexploitation often occurs because of the conflicting interests between individual exploiters and the public, and because individual exploiters often are maximizing short rather than long‐term benefits. When sustainable exploitation is attempted, significant practical challenges remain in determining particular exploitation levels that would guarantee chosen management goals. Good intentions may be ruined if uncertainty is not properly accounted for, and overexploitation may also result from lack of precaution.
Cytotoxicity of Aberrant Proteins
Authors: Ashok Aarthi , Hegde Ramanujan S
Published: December 2008

A wide range of diseases are caused by the generation of aberrant proteins that for one reason or another are not functionally equivalent to the normal version. Here, we consider the basic cellular principles that govern the generation of aberrant proteins, their normal metabolism and in the case of disease, their adverse effects on cellular function.

Key concepts

The organization of proteins inside cells is highly regulated at many levels.

Proteins that are not folded correctly or not trafficked to their intended destination are aberrant and have the potential to cause cellular dysfunction.

Numerous quality control systems constantly detect and degrade aberrant proteins.

Failure to either recognize or promptly degrade aberrant proteins can lead to their accumulation, and in some cases, their aggregation.

Misfolded or mislocalized proteins can interact inappropriately with other cellular factors to cause toxicity.

Most diseases of protein misfolding probably have multiple mechanisms that operate simultaneously to cause pathology.
Macrophages in Lipid and Immune Homeostasis
Authors: Neyen Claudine D , Gordon Siamon
Published: December 2008

Many components of the immune system play diverse roles in lipid metabolism and vice versa. Macrophage immune functions, including pathogen clearance and apoptotic cell removal, are regulated by lipids but also generate effectors that impact on lipid homeostasis. Oxidized lipids, byproducts of the oxidative burst, activate nuclear receptors, which not only orchestrate lipid homeostasis but also cross‐regulate NFκB‐driven immune responses. Activation of macrophages leads to cytokine production and induction of the acute phase response, accompanied by systemic lipid changes. Lipoproteins and their components, as well as lipid transport molecules, are emerging as novel actors in innate immune defence.
Ecosystem Engineers
Authors: Gutiérrez Jorge L , Jones Clive G
Published: December 2008

Ecosystem engineers
, or more precisely
physical ecosystem engineers
, are organisms that change the abiotic environment by physically altering structure. As a consequence they often, but not invariably, have effects on other biota and their interactions, and on ecosystem processes. The physical ecosystem engineering concept interconnects a number of important ecological and evolutionary concepts and is particularly relevant to environmental management.
Photon Activation Analysis
Authors: Segebade Christian , Berger Achim
Published: December 2008

In photon activation analysis (PAA), nuclides of the analyte elements in the material sample under study are converted to radioactive nuclides through exposure to high‐energy photons. Characteristic radiation upon disintegration of these radionuclides (preferably γ quanta) is then measured with appropriate spectrometers. PAA is not an “absolute” method; hence, the samples under investigation have to be irradiated together with a comparative material sample (calibration material) with well‐known chemical composition. After spectroscopic measurement of both samples, the quantitative evaluation is performed by comparison of the two resulting element spectra, basically following the same procedure as in most instrumental methods, e.g. ICP, AAS, etc. The particular advantages of this method are freedom from blank values; reduced danger of contamination; and, since frequent investigations can be carried out “nondestructively”, easy handling of materials that are difficult to treat chemically, e.g. certain refractory metals, dusts, ashes, etc. Another advantage is the option to study very small samples (a few milligrams) as well as very large ones (up to kilogram amounts). Basically, there are no limitations concerning the nature of material studied but matrices like lead or other heavy elements raise the limit of detection considerably, and separation techniques have to be used.
TLX1 (HOX11) Immortalization of Embryonic Stem Cell–Derived and Primary Murine Hematopoietic Progenitors
Authors: Hawley Robert G. , Hawley Teresa S. , Cantor Alan B.
Published: December 2008

The ability to generate genetically engineered cell lines is of great experimental value. They provide a renewable source of material that may be suitable for biochemical analyses, chromatin immunoprecipitation assays, structure‐function studies, gene function assignment, and transcription factor target gene identification. This unit describes protocols for TLX1 (HOX11)‐mediated immortalization of murine hematopoietic progenitors derived from in vitro differentiated murine embryonic stem cells, or from primary mouse fetal liver or bone marrow. A wide variety of hematopoietic cell types have been immortalized using these procedures including erythroid, megakaryocytic, monocytic, myelocytic, and multipotential cell types. These lines are typically cytokine dependent for their survival and growth. Curr. Protoc. Stem Cell Biol. 7:1F.7.1‐1F.7.19. © 2008 by John Wiley & Sons, Inc.
Control of Charge Transport in Iridium(III) Complex‐Cored Carbazole Dendrimers by Generation and Structural Modification
Authors: Gambino Salvatore , Stevenson Stuart G. , Knights Kevin A. , Burn Paul L. , Samuel Ifor D. W.
Published: December 2008

Here, the charge transporting properties of a family of highly phosphorescent iridium(III) complex‐cored carbazole dendrimers designed to have improved charge transport by incorporating carbazole units into the dendrons are studied. Firstly, the effect of the dendrimer generation and the role of dendron for materials with one dendron per ligand of the core are considered. It is shown, in contrast to previously reported light‐emitting dendrimers, that in this case the carbazolyl‐based dendrons have an active role in charge transport. Next, the effect on the charge transport of attaching two dendrons per ligand to the dendrimer core is explored. In this latter case, for the so called “double dendron” material a highly non‐dispersive charge transport behavior is observed, together with a time‐of‐flight mobility of the order of 10−3 cm2 V−1 s−1. Furthermore the lowest energetic disorder parameter (σ) ever reported for a solution‐processed conjugated organic material is found, σ <  20 meV.
Balancing Intermolecular and Molecule–Substrate Interactions in Supramolecular Assemblies
Authors: de Oteyza Dimas G. , Silanes Iñaki , Ruiz‐Osés Miguel , Barrena Esther , Doyle Bryan P. , Arnau Andrés , Dosch Helmut , Wakayama Yutaka , Ortega J. Enrique
Published: December 2008

Self‐assembly of functional supra‐molecular nanostructures is among the most promising strategies for further development of organic electronics. However, a poor control of the interactions driving the assembling phenomena still hampers the tailored growth of designed structures. Here exploration of how non‐covalent molecule‐substrate interactions can be modified on a molecular level is described. For that, mixtures of DIP and F16CuPc, two molecules with donor and acceptor character, respectively are investigated. A detailed study of their structural and electronic properties is performed. In reference to the associated single‐component layers, the growth of binary layers results in films with strongly enhanced intermolecular interactions and consequently reduced molecule‐substrate interactions. This new insight into the interplay among the aforementioned interactions provides a novel strategy to balance the critical interactions in the assembly processes by the appropriate choice of molecular species in binary supra‐molecular assemblies, and thereby control the self‐assembly of functional organic nanostructures.
Hearing loss among Ohio farm youth: A comparison to a national sample
Authors: Renick Katherine M. , Crawford J. Mac , Wilkins J.R.
Published: December 2008

Background

Hearing loss is prevalent among adults in the farming community, with some evidence it begins in childhood. Our objective was to compare hearing thresholds of Ohio farm youth to published data on national norms.

Methods

Baseline data were collected on youth (n = 212) in 1994–1996 with follow‐up (n = 132) in 2003–2004 including pure‐tone air conduction thresholds at 0.5, 1, 2, 3, 4, 6, and 8 kHz.

Results

When compared to nationally‐representative data, study youth had a higher prevalence of hearing loss. The high‐frequency range was most affected, particularly at 6 kHz where nearly 50% of the farm youth exhibited some degree of hearing loss at baseline testing. The prevalence of noise‐induced threshold shifts, characterized by an audiometric notch, was nearly twice that of the national sample.

Conclusions

These data suggest that hearing loss, which is common among adult farmers, may be problematic for farm youth as well. Am. J. Ind. Med. 52:233–239, 2009. © 2008 Wiley‐Liss, Inc.
Expression of Orexin A and Its Receptor 1 in the Vestibular Glands of the Cattle Genital Tract
Authors: Pavone Luigi Michele , Tafuri Simona , Avallone Luigi , Staiano Norma , Vittoria Alfredo
Published: December 2008

The hypothalamic peptide orexin A (oxA) binds specifically the G‐protein–coupled orexin receptor 1 (ox1R). It is involved in many physiological functions including the regulation of food intake, sleep–wake cycle, arterial blood pressure, heart rate, and sexual behavior. The localization of oxA in adrenal glands, stomach, bowel, pancreas, and testis has recently been assessed. Here, we provide the first evidence for the expression of oxA and ox1R in the vestibular glands of mammalian genital tract. Anat Rec, 2009. copy; 2008 Wiley‐Liss, Inc.
Phenotypic Plasticity and Function of the Hard Palate in Growing Rabbits
Authors: Menegaz Rachel A. , Sublett Samantha V. , Figueroa Said D. , Hoffman Timothy J. , Ravosa Matthew J.
Published: December 2008

Morphological variation related to differential loading is well known for many craniomandibular elements. Yet, the function of the hard palate, and in particular the manner in which cortical and trabecular bone of the palate respond to masticatory loads, remains more ambiguous. Here, experimental data are presented that address the naturalistic influence of biomechanical loading on the postweaning development and structure of the hard palate. A rabbit model was used to test the hypothesis that variation in the morphology of the hard palate is linked to variation in masticatory stresses. Rabbit siblings were divided as weanlings into soft and hard/tough dietary treatment groups of 10 subjects each and were raised for 15 weeks until subadulthood. MicroCT analyses indicate that rabbits subjected to elevated masticatory loading developed hard palates with significantly greater bone area, greater cortical bone thickness along the oral lamina, and thicker anterior palates. Such diet‐induced levels of palatal plasticity are comparable to those for other masticatory elements, which likely reflect osteogenic responses for maintaining the functional integrity of the palate vis‐à‐vis elevated stresses during unilateral mastication. These data support a role for mechanical loading in the determination of palatal morphology, especially its internal structure, in living and fossil mammals such as the hominin Paranthropus. Furthermore, these findings have potential implications for the evolution of the mammalian secondary hard palate as well as for clinical considerations of human oral pathologies. Anat Rec 2009. © 2008 Wiley‐Liss, Inc.
Assessment of Axonal Growth into Collagen Nerve Guides Containing VEGF‐Transfected Stem Cells in Matrigel
Authors: Kempton Laurence B. , Gonzalez Mark H. , Leven Robert M. , Hughes W. Frank , Beddow Sara , Santhiraj Yaveen , Archibald Simon J. , El Hassan Bassem , Shott Susan , Kerns James M.
Published: December 2008

The early events associated with axonal growth into 10‐mm nerve gaps were studied histologically in the rat sciatic nerve model to determine if the outgrowth of blood vessels, Schwann cells, and axons could be enhanced. In the first two experimental groups, collagen nerve guides were filled with either saline or Matrigel. Marrow‐derived mesenchymal stem cells (MSCs) were added to Matrigel in two other groups, one of which contained cells transfected with VEGF (MSC/VEGF). After 21 days, the injury site was exposed, fixed, sectioned, and volume fractions of the conduit contents were determined by point counting. The bioresorbable collagen conduits appropriately guided the axons and vessels in a longitudinal direction. The volume fraction of axons was significantly greater in the group with saline when compared with all three groups with Matrigel. This measure had a significant positive correlation with actual counts of myelinated axons. The blood vessel volume fraction in the Matrigel group decreased compared with the saline group, but was restored in the MSC/VEGF group. All Matrigel groups had comparable cellularity and showed a distribution of residual Matrigel in acellular zones. The saline group, by contrast, sustained a network of delicate fibroblastic processes that compartmentalized the nerve and its natural matrix as it became infiltrated by axons as minifascicles. In conclusion, the reduction of axonal outgrowth in the Matrigel groups, when compared with the saline group, suggests that Matrigel may impede the early regenerative process even when enriched by the addition of MSCs or VEGF‐transfected cells. Anat Rec, 2009. © 2008 Wiley‐Liss, Inc.
A survey of modern authorship attribution methods
Authors: Stamatatos Efstathios
Published: December 2008

Authorship attribution supported by statistical or computational methods has a long history starting from the 19th century and is marked by the seminal study of Mosteller and Wallace (1964) on the authorship of the disputed “Federalist Papers.” During the last decade, this scientific field has been developed substantially, taking advantage of research advances in areas such as machine learning, information retrieval, and natural language processing. The plethora of available electronic texts (e.g., e‐mail messages, online forum messages, blogs, source code, etc.) indicates a wide variety of applications of this technology, provided it is able to handle short and noisy text from multiple candidate authors. In this article, a survey of recent advances of the automated approaches to attributing authorship is presented, examining their characteristics for both text representation and text classification. The focus of this survey is on computational requirements and settings rather than on linguistic or literary issues. We also discuss evaluation methodologies and criteria for authorship attribution studies and list open questions that will attract future work in this area.
Do open‐access journals in library and information science have any scholarly impact? A bibliometric study of selected open‐access journals using Google Scholar
Authors: Mukherjee Bhaskar
Published: December 2008

Using 17 fully open‐access journals published uninterruptedly during 2000 to 2004 in the field of library and information science, the present study investigates the impact of these open‐access journals in terms of quantity of articles published, subject distribution of the articles, synchronous and diachronous impact factor, immediacy index, and journals' and authors' self‐citation. The results indicate that during this 5‐year publication period, there are as many as 1,636 articles published by these journals. At the same time, the articles have received a total of 8,591 Web citations during a 7‐year citation period. Eight of 17 journals have received more than 100 citations. First Monday received the highest number of citations; however, the average number of citations per article was the highest in D‐Lib Magazine. The value of the synchronous impact factor varies from 0.6989 to 1.0014 during 2002 to 2005, and the diachronous impact factor varies from 1.472 to 2.487 during 2000 to 2004. The range of the immediacy index varies between 0.0714 and 1.395. D‐Lib Magazine has an immediacy index value above 0.5 in all the years whereas the immediacy index value varies from year to year for the other journals. When the citations of sample articles were analyzed according to source, it was found that 40.32% of the citations came from full‐text articles, followed by 33.35% from journal articles. The percentage of journals' self‐citation was only 6.04%.
Hinterlüftete Außenwände, konstruiert aufgrund der von Karl Gertis erarbeiteten bauphysikalischen Grundlagen
Authors: Cziesielski Erich
Published: December 2008

Die grundlegende Arbeit über die Wirkungsweise und die geometrischen Randbedingungen bei der Konstruktion hinterlüfteter Außenwandkonstruktionen hat Karl Gertis mit seiner Habilitationsschrift verfasst. Auch in der geplanten Neufassung von DIN 18516‐1:2008‐09 wird auf die grundlegenden Ergebnisse seiner Arbeit unverändert zugegriffen werden. Weiterführende Arbeiten wurden unter anderem über die anzusetzenden Windlastannahmen und die korrosionshemmende Wirkung hinterlüfteter Außenwände von Janser und Marquardt durchgeführt. Durch die nachträgliche Montage von hinterlüfteten Außenwandkonstruktionen auf die geschädigten Wände des Großtafelbaus kann sowohl die Wärmedämmung verbessert werden als auch eine Sanierung der Fugen erfolgen; insbesondere wird aber durch das Aufbringen hinterlüfteter Außenwandkonstruktionen der Korrosionsschutz wesentlich verbessert. Im Folgenden werden die Wirkmechanismen hinsichtlich der Reduzierung der Windlast und des Korrosionsschutzes beschrieben.
Schalldämmung mit Vakuumisolationspaneelen: Messung und rechnerische Modellierung
Authors: Maysenhölder Waldemar
Published: December 2008

Die Luftschalldämmung von Vakuumisolationspaneelen (VIP) mit verschiedenen Stützmaterialien (Kieselsäure, Polyurethan u. a.) wurde messtechnisch im Prüfstand erfasst und rechnerisch mit dem IBP‐Programm LAYERS modelliert. Außerdem wurden mithilfe von Modalanalysen E‐Moduln und Verlustfaktoren bestimmt. Die untersuchten VIP verhalten sich akustisch in erster Näherung wie homogene, elastisch isotrope Platten. Dies ergibt sich aus dem Vergleich zwischen gemessenen und berechneten Schalldämmkurven. Die bewerteten Schalldämm‐Maße Rw liegen zwischen 18 und 29 dB, was in erster Linie durch die Masse des VIP bestimmt ist. Diskrepanzen zwischen E‐Moduln aus den Modalanalysen und den für LAYERS benutzten Werten lassen darauf schließen, dass die Frequenzabhängigkeit der elastischen Moduln – und damit auch der Verlustfaktoren – im Allgemeinen nicht vernachlässigbar ist. Bei Beschädigung (“Belüftung”) eines VIP verschlechtert sich die Schalldämmung in aller Regel – zum Teil drastisch, insbesondere wenn das Stützmaterial zusammensackt und das Paneel im oberen Teil sehr dünn und leicht wird. Mehrschichtige Aufbauten mit integriertem VIP (z. B. leichte Fassadenpaneele) erreichten im Prüfstand nicht ganz die aufgrund von LAYERS‐Prognosen erwartete Schalldämmung. Dies dürfte hauptsächlich auf die teilweise mangelhafte Verklebung der Schichten zurückzuführen sein. Mit LAYERS wurde gezeigt, dass sich eine VIP‐Verkleidung einer Massivwand in der Regel nicht negativ auf deren Schalldämmung auswirkt.
Ergebnisse einer Evaluierung von Energiekonzepten für Bürogebäude und Schlussfolgerungen für die Energieeffizienz und das Raumklima
Authors: Plesser Stefan , Kuchen Ernesto , Fisch M. Norbert
Published: December 2008

Bürogebäude sind seit den 1970‐er Jahren Teil öffentlicher Diskussion und intensiver wissenschaftlicher Untersuchungen. Eine Dringlichkeit erhielt der Untersuchungsbedarf von Energieeffizienz und Nutzerkomfort in den letzten 15 Jahren im Zuge der Entwicklung hin zu weitgehend verglasten Fassaden: die öffentliche Schelte für Architekten und Ingenieure sowie auch die teilweise fragwürdig geführte Fachdiskussion brachten Informationsdefizite zum Vorschein. Mit dem Ziel, dieses Informationsdefizit zu reduzieren, wurde das Forschungsprojekt “Evaluierung von Energiekonzepten für Bürogebäude (EVA)” durchgeführt. Es wurden 19 Bürogebäude untersucht.
Passivhaus contra bioclimatic design
Authors: Krainer Alesš
Published: December 2008

In recent years, Passivhaus has become religious movement. It steals into various European strategic documents like Action Plan for Energy Efficiency: Realising the Potential (2006) and Resolution of European Parliament (2007/2106(INI)). This article deals with the concept of internal environment and compares the passive and the bioclimatic concepts.
Adapting buildings to climate changes
Authors: Radu Adrian , Vasilache Maricica , Avram Costel
Published: December 2008

Attic floors are a favoured solution in refurbishing/rehabilitating residential buildings as well as for new buildings in Romania, under the conditions of climate changes and especially for adapting to the global warming phenomenon. Optimizing the thermal protection during the hot season can be made by a layer of ventilated air disposed directly under the roof covering. In order to analyse the ventilation process, and to establish design recommendations the authors have used a physical small scale model, in laboratory conditions, according the Grashof criterion. The paper is presenting a profitable utilization of similitude conditions leading to opportunities of analysing the indoor ventilation in passive system for a better energy efficiency.