bluuebunny/crossref_metadata_2025 huggingface dataset:
Economic Benefits Assessment of Accelerated Pavement Testing Research in California
Authors: du Plessis L. , Nokes W. A. , Mahdavi M. , Burmas N. , Holland T. J. , Lee E.-B.
Published: December 2011

A cost–benefit analysis method for determining the economic benefits of heavy vehicle simulator testing was evaluated. The University of California and its research partners began conducting accelerated pavement testing in 1994 on behalf of the California Department of Transportation. The authors present the findings of a pilot project intended to define a method suitable for measuring the direct economic benefits of heavy vehicle simulator testing in California. The chosen method was based on a cost–benefit analysis initially developed in Australia and later enhanced and applied in South Africa to determine economic benefits of their respective accelerated pavement testing programs. Results of a case study applying the Australian–South African method to heavy vehicle simulator tests conducted in California are presented. The case study evaluated benefits (in cost savings) from heavy vehicle simulator tests performed to validate innovative pavement mixes and designs proposed for the rehabilitation of a high-traffic urban Interstate route in the Los Angeles, California, area. Although local conditions in these countries differed significantly, the method was successfully applied and consistently showed positive results, presented as discounted net present value and benefit–cost ratio. Sensitivity analysis is recommended to determine a range of savings instead of a single benefit–cost ratio.
Measuring Influence of Accessibility on Accident Severity with Structural Equation Modeling
Authors: Kim Karl , Pant Pradip , Yamashita Eric
Published: December 2011

Structural equation modeling (SEM) is a confirmatory, multivariate technique used to examine causal relationships between variables. Related to path analysis with a goal of selecting a model that best explains underlying relationships between variables, SEM is a useful tool for traffic safety research. This study examined the severity of crashes in terms of factors commonly attributed to accidents. These factors included human, vehicle, and roadway factors, along with accessibility measures that were considered relevant in previous studies. In this study, SEM was used to test an a priori model of crash severity. The analysis was carried out in a two-step process. The measurement model was first tested with a confirmatory factor analysis. After the validity of the measurement model was established, a four-latent-factor structural model was run. With an acceptable model fit, the magnitude of standardized path coefficients from the exogenous latent variables provided a means to assess the relative importance of the latent factors on crash severity. The results showed that the human latent factor was the most influential. Although a positive statistical relationship existed between roadway factors and crash severity, accessibility factors had the opposite effect on crash severity, that is, increased accessibility was shown to reduce crash severity.
Effects of Mobile Phone Use on Accident Risk
Authors: Elvik Rune
Published: December 2011

This paper provides a meta-analysis of studies that have evaluated the effects of the use of a mobile phone while a person is driving on the risk of accident. The paper illustrates the difficulties of doing meta-analyses when studies are few and bad. Two main groups of studies were formed: one consisted of six studies that reported the actual use of mobile phones at the time of an accident; the other consisted of seven studies with less-precise information about the use of mobile phones at the time of accident. One study belonged to both groups. Study findings were heterogeneous even within these small groups. The trim-and-fill technique suggested the presence of publication bias, but its effects on summary estimates of risk varied according to whether a fixed-effects or random effects model of meta-analysis was used. Evidence from the epidemiological studies was not consistent with the findings of effects on driver behavior from driving simulator studies.
Analysis of Naturalistic Driving Event Data
Authors: Jovanis Paul P. , Aguero-Valverde Jonathan , Wu Kun-Feng , Shankar Venky
Published: December 2011

Naturalistic driving studies have been conducted over the past 5 years or more and have commonly reviewed video and kinematic data to identify and analyze crash, near-crash, and critical-incident events. But statistical methods that are applicable to these event data are needed. This paper addresses two issues in model development for naturalistic driving event data: the test for omitted-variable bias and the exploration of the advantages of hierarchical model structures in data analysis. With roadway departure event data from the 100-Car Naturalistic Driving Study conducted at Virginia Tech Transportation Institute, Blacksburg, Virginia, logit models were used to estimate the probability that a crash or a near crash would occur, rather than a critical incident. The models indicated a substantial omitted-variable bias for estimation of the effect of context variables but little difference for driver variables. These tests indicated that modeling of naturalistic event data should have included variables that described the attributes of the event, the driver, and the context to reduce the likelihood of bias. Hierarchical model structures offer the advantage of driver-level predictors to parameterize the effects of event attributes and contexts. The models thus reflect how driver decisions are executed: drivers with particular characteristics (one level) find themselves in contexts in which they execute specific driving maneuvers (second level), which lead to certain outcomes. Suggestions for further research include testing with additional data sets and potential applications to analysis of crash surrogates.
Development of Micromechanics Models and Innovative Sensor Technologies to Evaluate Internal Frost Damage of Concrete
Authors: Dai Qingli , Yu Xiong , Ng Kenny , Liu Zhen
Published: December 2011

Internal frost damage is a major problem affecting the durability of concrete in cold regions. Micromechanics models and innovative sensor technologies were used to study the mechanisms of frost damage in concrete. Crystallization pressure resulting from ice nucleation within capillary pores is the primary cause of internal frost damage of concrete. Crystallization pressure of a cylinder pore was formulated with interface energy balance with thermodynamics analysis. Crystallization pressure on the pore wall was input for fracture simulation with the extended finite element model on a homogeneous beam sample with a vertical cylinder pore; this simulation led to a straight line. An image sample was obtained with imaging process and ellipse fitting techniques to capture microstructure of a tested specimen. Crack simulation of this image sample with the same cylinder pore under crystallization pressure matched fracture patterns of the single-edge-notched bending specimen. Extended finite element model simulation results were verified by open-mode fracture behavior in middle-notched single-edge-notched bending and freezing tests. An innovative time-domain reflectometry sensor was developed to nondestructively monitor the freezing process. Data show that sensor signals from time-domain reflectometry can detect the freezing degree, an important input parameter. Studies indicate that the micromechanics models and time-domain reflectometry sensor techniques can help practitioners evaluate internal frost damage of concrete. Future work will incorporate sensor measurements into micromechanics models to predict, in real time, internal frost damage process in concrete specimens. The goal of this study was to provide practical nondestructive testing and computational tools for designing concrete that is resistant to freezing damage.
Cyclic Heat Island Impacts on Traditional versus Pervious Concrete Pavement Systems
Authors: Haselbach Liv , Boyer Michelle , Kevern John T. , Schaefer Vernon R.
Published: December 2011

As the world becomes more urbanized, concerns over the urban heat island (UHI) are more pronounced. Increased urban temperatures have a negative affect on the natural and human environment by producing increased energy usage and smog formation. Pervious concrete pavement is one technology that may help mitigate increased urban temperatures. Temperature data from an instrumented site in Iowa and heat storage phenomena for various weather patterns are presented. The site contains both pervious concrete pavement with a solar reflectance index (SRI) of 14 and traditional concrete pavement with an SRI of 37. Leadership in Energy and Environmental Design (LEED) accepted a high SRI (>29) as one method to characterize a cool surface. Heat capacities of both systems were studied along with a sensitivity analysis of the inputs. The research supports the conclusion that even though pervious concrete may have a much lower SRI than traditional concrete made with similar materials, it can be considered a cool pavement option. In addition, daytime rainfalls combined with the internal high surface area result in significantly more removal of stored heat from the system, with a more rapid mitigation of UHI impacts and reduction in the potential for thermal shock from impervious surface runoff.
Migration, Agribusiness and Nutritional Status of Children under Five in Northwest Mexico
Authors: Ortega María-Isabel , Rosales Cecilia , Zapien Jill Guernsey de , Aranda Patricia , Castañeda Alejandro , Saucedo Socorro , Montaño Cecilia , Contreras Alma
Published: December 2011

The aim of this study was to examine the nutritional status of children of Mexican migrant worker families under five years of age within the context of global food markets. The sample included 404 children less than five years old from farms and agricultural communities in northwest Mexico. Prevalence of stunting and underweight of children appeared very similar to that of indigenous children from the national sample survey (difference 0.9 and 1.6 percentage points, respectively). Compared to the national sample of Mexican children, stunting and underweight seemed higher in migrant children (difference 17.7 and 4.5 percentage points, respectively), but wasting, an indicator of both chronic and acute undernutrition, appeared to indicate a process of nutritional recuperation. Migrant children living in poverty and suffering from chronic undernutrition, poor performance and scarce education opportunities, can be expected to eventually become agricultural workers with low productivity and poor general health. Consumer’s demands on social and environmental standards of fresh food production in developed countries could be an opportunity to impact the lives of migrant agricultural workers, their families and communities.
Oligosaccharides Might Contribute to the Antidiabetic Effect of Honey: A Review of the Literature
Authors: Erejuwa Omotayo O. , Sulaiman Siti A. , Wahab Mohd S. Ab
Published: December 2011

Evidence shows that honey improves glycemic control in diabetes mellitus. Besides its hypoglycemic effect, studies indicate that honey ameliorates lipid abnormalities in rats and humans with diabetes. The majority of these studies do not examine the mechanisms by which honey ameliorates glycemic and/or lipid derangements. The gut microbiota is now recognized for its ability to increase energy harvest from the diet and alter lipid metabolism of the host. Recently available data implicate a causal role of these gut microbes in the pathophysiology of obesity, insulin resistance, and diabetes mellitus. In this review, we present some of the latest findings linking gut microbiota to pathogenesis of obesity, insulin resistance, and diabetes mellitus. The review also underlines data that demonstrate the beneficial effects of oligosaccharides on various abnormalities commonly associated with these disorders. Based on the similarities of some of these findings with those of honey, together with the evidence that honey contains oligosaccharides, we hypothesize that oligosaccharides present in honey might contribute to the antidiabetic and other health-related beneficial effects of honey. We anticipate that the possibility of oligosaccharides in honey contributing to the antidiabetic and other health-related effects of honey will stimulate a renewed research interest in this field.
Neonaucline, a New Indole Alkaloid from the Leaves of Ochreinauclea maingayii (Hook. f.) Ridsd. (Rubiaceae)
Authors: Mukhtar Mat Ropi , Osman Norfaizah , Awang Khalijah , Hazni Hazrina , Qureshi Ahmad Kaleem , Hadi A. Hamid A. , Zaima Kazuma , Morita Hiroshi , Litaudon Marc
Published: December 2011

A new indole alkaloid; neonaucline (1), along with six known compounds–Cadamine (2), naucledine (3), harmane, benzamide, cinnamide and blumenol A–were isolated from the leaves of Ochreinauclea maingayii (Rubiaceae). In addition to that of compound 1, 13C-NMR data of cadamine (2) and naucledine (3) were also reported. Structural elucidations of these alkaloids were performed using spectroscopic methods especially 1D- and 2D-NMR, IR, UV and LCMS-IT-TOF. The excellent vasorelaxant activity on isolated rat aorta was observed for the alkaloids 1–3 after injection of each sample at 1 × 10−5 M.
Animal mon frère, toi Un livre, une histoire, une logique
Authors: Vegh Isidoro
Published: December 2011

Résumé L’auteur revient sur «?l’affaire?» Tausk et la relation problématique entre lui, Freud et son analyste, Helene Deutsch, révélée en son temps par Paul Roazen.
Rien en savoir
Authors: Mevel Françoise
Published: December 2011

Résumé Être un «?bon parent?» se mesure aussi, actuellement, à l’inscription de l’enfant dans le cadre scolaire. Si l’enfant résiste à ce savoir, le champ social a inventé des signifiants catégoriels?: «?enfants tyrans?», «?enfants précoces?», «?phobies scolaires?». Cette injonction à la performance scolaire fait osciller l’économie familiale entre effondrement parental et excitation enfantine. Une thérapie familiale vient illustrer le propos de l’auteur, particulièrement une séance où le travail autour d’une phrase écrite métaphorisera l’évolution de la structure familiale.
Shaping the alliance management agenda: a capability approach
Authors: Duysters Geert , Saebi Tina , De Man Ard-Pieter
Published: December 2011

Over the past years, the topic of alliance capability has captured the attention of numerous alliance scholars. This emerging research stream claims that a main cause for alliance success lies in the partner's individual capability to manage their alliances. This editorial paper reviews the main contributions and advancements in alliance capability literature and draws lessons from this literature on how alliance capability research has fundamentally reshaped the research agenda in alliance management.
Rapid determination of patulin in medicinal hawthorn fruits by HPLC-MS/MS
Authors: Xiang L. , Gao Y. , Liu D. , Yang M.
Published: December 2011

An HPLC-tandem mass spectrometry method was developed for the determination of patulin (PAT) in dried
medicinal hawthorn fruit, a well-known traditional medicine in China. Liquid-liquid extraction was applied in the
sample preparation. Multiple reaction monitoring was performed at m/z 153/109 for PAT and m/z 317/273 for
internal standard zearalenone in the negative ion mode with electrospray ionisation source. Good linearity was
achieved when spiked PAT concentrations were in the range of 10-500 μg/kg, with coefficient being 0.9993. The
limit of quantitation was 10 μg/kg. The extraction recoveries for the spiked PAT at concentrations of 20, 100 and
400 μg/kg were 64.5%, 64.6% and 63.9%, respectively, with relative standard deviations of 1.25%, 2.82% and 2.61%.
The intra-day and inter-day precision were in the range of 2.2-9.6% and 5.9-6.4%. This rapid, sensitive and reliable
method was applied in 25 batches of medicinal hawthorn fruit, in which PAT was detected in 8 batches, including
those that were baked or charred.
Labra de época romana en Hispania
Authors: Morillo Ángel , Salido Domínguez Javier
Published: December 2011

Los lavabos, pilas o tazas de fuente circulares son elementos funcionales y decorativos bastante comunes en el mundo romano donde recibían el nombre de labra. Dentro de esta categoría se han incluido a menudo también las tazas rectangulares, para las que se prefiere reservar el término alvei. En el ámbito de la antigua Hispania estos elementos han pasado bastante desapercibidos, lo que obedece a un problema de publicación más que de una ausencia en el registro arqueológico. En algunas ocasiones, la confusión terminológica ha llevado a identificar las fuentes no como el elemento arquitectónico o escultórico del que brotaba el agua, sino con el espacio físico donde se ubicó aquel. La revisión historiográfica de los labra documentados hasta el momento en la Península Ibérica, tanto en ámbitos públicos como privados, nos ha permitido analizar su procedencia, tipología, funcionalidad y material de fabricación, además de su contexto arqueológico. Fabricados en marmora de diferentes variedades, locales e importados, las tazas de fuente, que presentan diferentes tamaños y morfología, suelen estar vinculadas a edificios termales, así como a atrios y peristilos.
El Templum Divi Claudii. Decoración y elementos arquitectónicos para su reconstrucción
Authors: Domingo Javier Á. , Mar Ricardo , Pensabene Patrizio
Published: December 2011

Hasta el momento disponíamos de pocos datos del Templum Divi Claudii, dedicado por Agripina a su difunto esposo divinizado; apenas un esquemático dibujo realizado en el s. XVI de la pieza de la FUR correspondiente al templo, así como algunos escasos fragmentos de esta misma planta marmórea correspondientes al temenos. Sin embargo, gracias a la localización de algunos elementos de la decoración arquitectónica del templo, ahora, finalmente, podemos realizar una reconstrucción volumétrica del edificio y descubrir cómo su construcción participó plenamente de la tradición de la arquitectura gigantesca iniciada por Augusto con el templo de Mars Ultor. Sus medidas, prácticamente idénticas a las de este templo, ofrecen además la posibilidad de vincular a los emperadores Claudio y Vespasiano, restaurador del Claudianum, con Augusto.
Cubierta de sarcófago con el ciclo de Jonás hallada en Carranque (Toledo)
Authors: Fernández Ochoa Carmen , Bendala Galán Manuel , García-Entero Virginia , Vidal Álvarez Sergio
Published: December 2011

En el presente trabajo se da a conocer la tapa de sarcófago hallada en el yacimiento de Carranque (Toledo) en la campaña de 2009. La pieza, conservada casi íntegramente, fue reutilizada como parte del sistema de cubierta de una de las tumbas que formó parte de la necrópolis visigoda instalada sobre parte del antiguo Palatium tardorromano durante el siglo VII. Se trata de una tapa de sarcófago tipo frontis en cuyo frente se representa el ciclo del profeta Jonás que aparece en tres escenas consecutivas que cubren la totalidad del frente. Los análisis petrológicos realizados en el ICAC han permitido confirmar que se trata de mármol de Estremoz y, por tanto, que nos hallamos ante una pieza elaborada en un taller hispano de excelente calidad que estuvo en funcionamiento en las últimas décadas del siglo IV d.C., momento en el que datamos la pieza hallada en Carranque.
Las excavaciones de Gabriel Llabrés, Rafael Isasi y Juan Llabrés en la ciudad romana de Pollentia (Alcudia, Mallorca) (1923-1946)
Authors: Vallori Márquez Bartomeu , Orfila Pons Margarita , Cau Ontiveros Miguel Ángel
Published: December 2011

La tradición arqueológica en la ciudad romana de Pollentia (Alcudia, Mallorca) se remonta a la intervención de G. Llabrés y R. Isasi en 1923. Sus trabajos se prolongaron con cierta regularidad hasta 1946 y afectaron a amplias zonas realizando hallazgos destacables. En este artículo, se presenta el resultado de la consulta de documentación inédita acerca de estas intervenciones. Esto ha permitido reconstruir las campañas de excavación, especialmente las de 1942 a 1946, muy poco conocidas hasta ahora, y situarlas en la planta general del yacimiento, lo que supone un avance significativo en el conocimiento topográfico de esta ciudad romana de provincias.
Effect of Prenatal Exposure to Lead on Estrogen Action in the Prepubertal Rat Uterus
Authors: Tchernitchin Andrei N. , Gaete Leonardo , Bustamante Rodrigo , Báez Aracelly
Published: December 2011

Lead is a widely spread environmental pollutant known to affect both male and female reproductive systems in humans and experimental animals and causes infertility and other adverse effects. The present paper investigated the effects of prenatal exposure to lead on different parameters of estrogen stimulation in the uterus of the prepubertal rat. In prenatally and perinatally exposed rats, estrogen-induced endometrial eosinophilia, endometrial stroma edema, and eosinophil migration towards the endometrium, and uterine luminal epithelial hypertrophy are enhanced while several other responses to estrogen appear unchanged. These effects may contribute to decrease in fertility following prenatal exposure to lead. The striking difference between most of these effects of prenatal exposure and the previously reported effects of chronic exposure to lead suggests that prenatal exposure to lead may neutralize the effects of chronic exposure to lead, providing partial protection of cell function against the adverse effects of chronic exposure to lead. We propose that the mechanism involved, named imprinting or cell programming, persisted through evolution as a nongenetic adaptive mechanism to provide protection against long-term environmental variations that otherwise may cause the extinction of species not displaying this kind of adaptation.
Squares and Pegs
Authors: Mooney Edward S. , Sherry L. Bair
Published: December 2011

Student solutions are given to a geoboard problem involving the Pythagorean theorem.
Damage domains of chemically reacting industrial facilities. An adequate identification model for Bhopal‐like scenarios
Authors: Benikhlef Taha , Benazzouz Djamel , Izquierdo José M. , Sanchez Miguel
Published: December 2011

This paper focuses on the improvement of solutions to some of the problems that arise in chemical and petrochemical risk assessment studies, namely those associated with potentially undue grouping in sequences of events, caused by different time evolutions. It provides an adequate work‐horse simulation model of risky scenarios able to explore a large amount of transients at a reasonable and viable cost. It is specifically suitable for the transfer of modern dynamic reliability techniques, originated in the nuclear domain, to the chemical engineering environment. As an application, it presents results of a case study to analyse Bhopal‐like scenarios. We found the model adequate to discriminate and filter out the myriad of success scenarios expected in well‐protected installations, screening necessary to focus the risk studies on damage situations. © 2011 Curtin University of Technology and John Wiley & Sons, Ltd.
Surface modification of polypropylene membrane by acrylate epoxidized soybean oil to be used in water treatment
Authors: Palacios‐Jaimes Martha Liliana , Cortes‐Guzman Fernando , González‐Martínez David Alejandro , Gómez‐Espinosa Rosa María
Published: December 2011

Surface modification of a microporous polypropylene (PP) membrane was performed by graft polymerization of acrylated epoxidized soybean oil (AESO) using UV radiation. This is a simple, environmentally friendly, and low cost method. The factors affecting the grafting degree such as monomer concentration and reaction time were studied. The morphological and microstructure changes of the membrane were characterized by scanning electron microscopy (SEM) and information regarding elemental composition was obtained by energy dispersive X‐ray spectroscopy (EDS). Surface functionalization was studied by X‐ray photoelectron spectroscopy (XPS). Thermal properties were analyzed by differential scanning calorimetry (DSC). The hydrophilicity increment was confirmed by pure water contact angle and swelling measurements. The filtration capability of the modified membrane was analyzed by determining color, turbidity, and chemical oxygen demand (COD) removal from a residual raw water. The results indicated that the contact angle of pure water on the grafted membrane decreased from 90° to 57°. The modified membrane shows filtration capability by removing color in 52% and reducing 95% of turbidity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Novel poly(azomethine‐urethane)s and their polyphenol derivatives derived from aliphatic diisocyanate compound: Synthesis and thermal characterization
Authors: Kaya İsmet , Kamacı Musa
Published: December 2011

Until now, only a few kinds of poly(azomethine‐urethane)s (PAMUs) including aromatic hydroxy benzaldehyde and aminophenol compounds were obtained and studied with thermal degradation steps. However, oligo/polyphenol‐based PAMUs have not been synthesized yet. In this study, some kinds of this class of PAMUs were synthesized in three steps. At the first step polyurethane (PU) was synthesized by the copolymerization reaction of 2,4‐dihydroxybenzaldehyde with hexamethylene diisocyanate (HDI) under argon atmosphere. At the second step, the poly(azomethine‐urethane)s (PAMUs) were obtained by graft copolymerization of the preformed PU with aminophenols (2‐aminophenol, 3‐aminophenol, and 4‐aminophenol). At the last step the obtained PAMUs were converted to the polyphenol derivatives via oxidative polycondensation reaction (OP). The structures of the obtained compounds were confirmed by FTIR, UV‐vis, 1H‐NMR, and 13C‐NMR techniques. The number‐average molecular weight (Mn), weight average molecular weight (Mw) and polydispersity index (PDI) values of the synthesized compounds were determined by the size exclusion chromatography (SEC). The synthesized compounds were also characterized by solubility tests, TG‐DTA, and DSC. Fluorescence measurements were carried out in various concentrated DMF solutions to determine the optimum concentrations to obtain the maximal PL intensities. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Development of a compact capillary electrophoresis–chemiluminescence system with ultra‐fast peroxyoxalate reaction to monitor the hydrolysis of rhodamine 6G
Authors: Zhu Jinkun , Shu Lu , Zhang Fan , Li Zicheng , Wang Qingjiang , He Pingang , Fang Yuzhi
Published: December 2011

A simple and effective capillary electrophoresis–chemiluminescence (CE–CL) detection system was developed based on an ultra‐fast bis(2,4,6‐trichlorophenyl)oxalate (TCPO) chemiluminescence (CL) reaction (0.6 s duration) that avoided overlapping peaks and peak tailing. Through a series of static injection experiments, this unusually rapid CL reaction was ascribed to the catalytic effect of imidazole in the tetrahydrofuran solvent, which has been rarely utilized in such investigations. A possible mechanism is given to explain the results. Under the optimized conditions, rhodamine 6 G (R6G) and its hydrolysis product (R6G‐COOH) could be efficiently separated through electrophoresis in 7 min, with sensitive CL detection in the proposed CE–CL system. In this way, the alkaline hydrolysis of R6G was monitored, followed by estimation of relative rate constants and activation energy. This finding and application should be helpful in further study for the TCPO CL reaction, and revealed an attractive opportunity for simplifying the CE–CL system, such as in a microchip device. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and Characterization of Photoswitchable Fluorescent SiO2 Nanoparticles
Authors: May Florian , Peter Michael , Hütten Andreas , Prodi Luca , Mattay Jochen
Published: December 2011

Switchable fluorescent silica nanoparticles have been prepared by covalently incorporating a fluorophore and a photochromic compound inside the particle core. The fluorescence can be switched reversibly between an on‐ and off‐state via energy transfer. The particles were synthesized using different amounts of the photoswitchable compound (spiropyran) and the fluorophore (rhodamine B) in a size distribution between 98 and 140 nm and were characterized in terms of size, switching properties, and fluorescence efficiency by TEM, and UV\Vis and fluorescence spectroscopy.
Phosphofructokinase type 1 kinetics, isoform expression, and gene polymorphisms in cancer cells
Authors: Moreno‐Sánchez Rafael , Marín‐Hernández Alvaro , Gallardo‐Pérez Juan Carlos , Quezada Héctor , Encalada Rusely , Rodríguez‐Enríquez Sara , Saavedra Emma
Published: December 2011

Kinetic analysis of PFK‐1 from rodent AS‐30D, and human HeLa and MCF‐7 carcinomas revealed sigmoidal [fructose 6‐phosphate, Fru6P]‐rate curves with different Vm values when varying the allosteric activator fructose 2,6 bisphosphate (Fru2,6BP), AMP, Pi, NH, or K+. The rate equation that accurately predicted this behavior was the exclusive ligand binding concerted transition model together with non‐essential hyperbolic activation. PFK‐1 from rat liver and heart also exhibited the mixed cooperative‐hyperbolic kinetic behavior regarding activators. Lowering pH induced decreased affinity for Fru6P, Fru2,6BP, citrate, and ATP (as inhibitor); as well as decreased Vm and increased content of inactive (T) enzyme forms. High K+ prompted increased (Fru6P) or decreased (activators) affinities; increased Vm; and increased content of active (R) enzyme forms. mRNA expression analysis and nucleotide sequencing showed that the three PFK‐1 isoforms L, M, and C are transcribed in the three carcinomas. However, proteomic analysis indicated the predominant expression of L in liver, of M in heart and MCF‐7 cells, of L > M in AS‐30D cells, and of C in HeLa cells. PFK‐1M showed the highest affinities for F6P and citrate and the lowest for ATP (substrate) and F2,6BP; PFK‐1L showed the lowest affinity for F6P and the highest for F2,6BP; and PFK‐1C exhibited the highest affinity for ATP (substrate) and the lowest for citrate. Thus, the present work documents the kinetic signature of each PFK‐1 isoform, and facilitates the understanding of why this enzyme exerts significant or negligible glycolysis flux‐control in normal or cancer cells, respectively, and how it regulates the onset of the Pasteur effect. J. Cell. Biochem. 113: 1692–1703, 2012. © 2011 Wiley Periodicals, Inc.
Proteomic identification of PSF and p54(nrb) as topBP1‐interacting proteins
Authors: Kuhnert Anja , Schmidt Uta , Monajembashi Shamci , Franke Claudia , Schlott Bernhard , Grosse Frank , Greulich Karl Otto , Saluz Hans‐Peter , Hänel Frank
Published: December 2011

TopBP1 is a BRCT domain‐rich protein that is structurally and functionally conserved throughout eukaryotic organisms. It is required for the initiation of DNA replication and for DNA repair and damage signalling. To further dissect its biological functions, we explored TopBP1‐interacting proteins by co‐immunoprecipitation assays and LC‐ESI‐MS‐analyses. As TopBP1 binding partners we identified p54(nrb) and PSF, and confirmed the physical interactions by GST pull‐down assays, co‐immunoprecipitations and by yeast two‐hybrid experiments. Recent evidence shows an involvement of p54(nrb) and PSF in DNA double‐strand break repair (DSB) and radioresistance. To get a first picture of the physiological significance of the interaction of TopBP1 with p54(nrb) and PSF we investigated in real time the spatiotemporal behaviour of the three proteins after laser microirradiation of living cells. Localisation of TopBP1 at damage sites was noticed as early as 5 s following damage induction, whereas p54(nrb) and PSF localised there after 20 s. Both p54(nrb) and PSF disappeared after 200 s while TopBP1 was retained at damage sites significantly longer suggesting different functions of the proteins during DSB recognition and repair. J. Cell. Biochem. 113: 1744–1753, 2012. © 2012 Wiley Periodicals, Inc.
Overexpression of 5‐lipoxygenase and its relation with cell proliferation and angiogenesis in 7,12‐dimethylbenz(α)anthracene‐induced rat mammary carcinogenesis
Authors: Chatterjee Mary , Das Subhadeep , Roy Kaushik , Chatterjee Malay
Published: December 2011

The present study was performed to investigate the critical role of 5‐lipoxygenase (5‐LOX) in 7,12‐dimethylbenz(α)anthracene (DMBA)‐induced rat mammary inflammation associated carcinogenesis. Female Sprague–Dawley rats at 50 days of age were treated with 7,12‐dimethylbenz(α)anthracene (DMBA; 0.5 mg/100 g body weight) by a single tail vein injection, followed by administration of zileuton (2000 mg/kg diet) from week 7 until the termination of the study at 31 wk. 5‐LOX protein expression, 5‐hydroxyeicosatetraenoic acid (5‐HETE), and leukotriene B4 (LTB4) production in rat mammary tissue were analyzed at 6, 12, and 24 wk post‐DMBA injection. Rate of cell proliferation was analyzed by bromodioxyuridine labeling index (BrdU‐LI). Microvessel density, level of VEGF, and MMP‐2 were also measured. DMBA induces inflammation in rat mammary gland as early as 6 wk. 5‐LOX is upregulated in DMBA treated rats right from 6 wk when compared with their normal counterparts. An overexpression of 5‐LOX is accompanied with increase in 5‐HETE, LTB4 production and high BrdU‐LI with an increase of two key angiogenic factors for tumorigenesis; MMP‐2 and VEGF. It was found that 5‐LOX specific inhibitor brought about substantial protection against DMBA‐induced mammary carcinogenesis. Histological findings showed substantial repair of hyperplastic lesions. There was a significant reduction in the rate of cell proliferation and expression of angiogenic factors, MMP‐2 and VEGF. 5‐LOX plays an important role in DMBA‐induced inflammation associated carcinogenesis via activation of MMP‐2 and VEGF. 5‐LOX expression can be considered as a critical event in controlling the process of mammary tumor development. © 2011 Wiley Periodicals, Inc.
Evaluation of combined bevacizumab plus irinotecan therapy in brain tumors using magnetic resonance imaging measures of relative cerebral blood volume
Authors: Pechman Kimberly R. , Donohoe Deborah L. , Bedekar Devyani P. , Kurpad Shekar N. , Schmainda Kathleen M.
Published: December 2011

Frequently, bevacizumab is combined with chemotherapeutics such as irinotecan, motivated by studies showing improved clinical outcomes compared with historical controls. However, no systematic studies have been performed to determine if and how these drugs should be combined for optimal therapeutic response. The purpose of this study was to characterize the temporal combinations of bevacizumab and irinotecan by measuring the contrast‐agent enhanced tumor volumes and relative cerebral blood volume using dynamic susceptibility contrast imaging. The studies, performed in the U87 brain tumor model, show a vascular normalization window with bevacizumab monotherapy and are consistent with clinical indications of no additional benefit in the addition of irinotecan to bevacizumab therapy. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Hydrogen desorption from a Si(111)1×1 surface studied by sum frequency generation spectroscopy and microscopy
Authors: Hien Khat Thi Thu , Miyauchi Yoshihiro , Kikuchi Masahiro , Mizutani Goro
Published: December 2011

We studied isothermal hydrogen desorption from a Si(111)1×1 surface at temperatures of ~711, 732, 752, and 771 K by observing sum frequency generation (SFG). Peak shift and width broadening of the Si‐H vibration occurred with increase of heating time. We also obtained SFG intensity images of monohydride species on the surface after heating for 10 s at temperatures of 592, 625, 666, 728, and 752 K. The SFG intensity images with a spatial resolution of 5 µm indicated that the hydrogen desorption was homogeneous. This result suggests that the hydrogen atoms diffused homogeneously on the Si(111)1×1 surface. Copyright © 2011 John Wiley & Sons, Ltd.
In vivo dopaminergic and behavioral responses to acute cocaine are altered in adenosine A2A receptor knockout mice
Authors: Wells Lisa , Opacka‐Juffry Jolanta , Fisher Donald , Ledent Catherine , Hourani Susanna , Kitchen Ian
Published: December 2011

Adenosine, acting on adenosine A2A receptors (A2ARs), regulates addictive processes induced by drugs of abuse. This study investigates the role of A2A adenosine receptors in neurochemical and behavioral responses to an acute cocaine challenge. Changes in the extracellular levels of dopamine (DA) in the nucleus accumbens (NAc) of mice lacking A2A adenosine receptors and wild type (WT) littermates after an acute cocaine (20 mg/kg) administration were evaluated by in vivo microdialysis studies. Locomotor effects induced by cocaine were measured during the microdialysis procedure. Cocaine‐evoked increases in extracellular DA were not sustained in mice lacking A2ARs in comparison with wild‐type mice (P < 0.05). Cocaine administration significantly increased ambulatory activity in both genotypes. However, overall locomotor activity was further increased, whereas rest and small local movement measures were significantly attenuated in the A2AR knockout mice compared with WT littermates (P < 0.05). Our findings support an important role for adenosine A2AR in modulating the acute effects of cocaine, as demonstrated by the decrease in cocaine‐evoked dopaminergic transmission in the NAc. Furthermore, the results support an important antagonistic role of A2AR in vivo in regulating psychostimulant‐induced hyperlocomotion. Synapse, 2012. © 2011 Wiley Periodicals, Inc.
Multiple Lymphatic Basin Drainage from Cutaneous Melanoma as a Prognostic Factor
Authors: Piñero Antonio , de Torre Carlos , Martínez‐Escribano Jorge , Campillo Juana , Canteras Manuel , Nicolás Francisco
Published: December 2011

Background

There is some controversy in the literature regarding the possible prognostic value of cases of multiple lymphatic basin drainage (MLBD). The purpose of this work was to study the differences in prognosis depending on whether there is MLBD from primary cutaneous melanoma.

Methods

We conducted a cohort analysis from a prospective database, and 112 consecutive patients with cutaneous melanoma were included. Sentinel lymph node biopsy (SLNB) was done in all of them. MLBD was defined as the occurrence of two or more different nodal basins from the same lesion. The demographic and clinical data for cases with a single nodal drainage basin and MLBD were statistically compared using Fisher’s exact test, the χ2 test, or Mann–Whitney’s test according to the type of variables studied. Multivariate analysis also was performed on the disease‐free survival rate using logistic regression analysis. The distribution of disease‐free survival was determined using a Cox proportional risk model.

Results

Only gender (27% men and 8% women; P = 0.01) and the localization of the primary tumor in the trunk (P < 0.001) were associated with the presence of MLBD. It also was observed that the cases with a high Breslow thickness or with MLBD were only associated with a worse disease‐free survival rate in cases with positive (P < 0.01 and P = 0.047, respectively) and negative (P < 0.011 and P = 0.019, respectively) SLNB.

Conclusions

This study suggests that both Breslow thickness and the presence of MLBD are statistically significant independent prognostic factors of disease‐free survival in patients with cutaneous melanoma.
Relationship Between Linguistic Antonyms in Momentary and Retrospective Ratings of Happiness and Sadness
Authors: Kööts Liisi , Realo Anu , Allik Jüri
Published: December 2011

Momentary ratings of affective states with a pair of strict antonyms (“happy” vs. “sad”) were studied with an experience-sampling method in a group of 110 participants during 14 consecutive days at 7 randomly determined occasions per day. Before and after the experimental session participants also retrospectively rated how happy or sad they had been during the previous 2 weeks. Multilevel analysis showed that, at the level of single measurement trials, the momentary ratings of happiness and sadness were moderately negatively correlated (r = –.32, p < .001). A between-subject correlation of the two antonyms, however, was in a positive direction (r = .13, p = .123). Participants experienced mixed feelings during a considerable number of measurement trials, whereas the tendency to feel mixed emotions was predicted by all Big Five personality traits except Agreeableness. A configural frequency analysis (CFA) demonstrated that, although there was no strict bipolarity between momentary ratings of happiness and sadness, they were nevertheless used in an exclusive manner in many occasions.
Fixed recurrence and slip models better predict earthquake behavior than the time‐ and slip‐predictable models: 1. Repeating earthquakes
Authors: Rubinstein Justin L. , Ellsworth William L. , Chen Kate H. , Uchida Naoki
Published: December 2011

The behavior of individual events in repeating earthquake sequences in California, Taiwan and Japan is better predicted by a model with fixed inter‐event time or fixed slip than it is by the time‐ and slip‐predictable models for earthquake occurrence. Given that repeating earthquakes are highly regular in both inter‐event time and seismic moment, the time‐ and slip‐predictable models seem ideally suited to explain their behavior. Taken together with evidence from the companion manuscript that shows similar results for laboratory experiments we conclude that the short‐term predictions of the time‐ and slip‐predictable models should be rejected in favor of earthquake models that assume either fixed slip or fixed recurrence interval. This implies that the elastic rebound model underlying the time‐ and slip‐predictable models offers no additional value in describing earthquake behavior in an event‐to‐event sense, but its value in a long‐term sense cannot be determined. These models likely fail because they rely on assumptions that oversimplify the earthquake cycle. We note that the time and slip of these events is predicted quite well by fixed slip and fixed recurrence models, so in some sense they are time‐ and slip‐predictable. While fixed recurrence and slip models better predict repeating earthquake behavior than the time‐ and slip‐predictable models, we observe a correlation between slip and the preceding recurrence time for many repeating earthquake sequences in Parkfield, California. This correlation is not found in other regions, and the sequences with the correlative slip‐predictable behavior are not distinguishable from nearby earthquake sequences that do not exhibit this behavior.
Analysis of cirrus in the tropical tropopause layer from CALIPSO and MLS data: A water perspective
Authors: Wang Tao , Dessler Andrew E.
Published: December 2011

Two mechanisms are thought to be primarily responsible for the formation of cirrus in the Tropical Tropopause Layer (TTL): detrainment from deep convective anvils and in situ initiation. By analyzing water vapor (H2O) measurements from the Aura Microwave Limb Sounder (MLS) and ice water content (IWC) measurements from the Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO), we identify TTL cirrus that contain too much ice to have been formed in situ—and therefore must be of convective origin. Analyzing 3 years of CALIPSO measurements (2008–2010), we found three maxima in the occurrence of convective cirrus: equatorial Africa, the tropical western Pacific, and South America. Over the entire tropics, we found that convective cirrus occur more frequently during boreal winter‐spring and less frequently during boreal summer‐fall. The convective fractions of cirrus also increase until the cold point tropopause is reached in most seasons—implying higher probabilities of cirrus around the tropopause being of convective origin. Averaged over 3 years, we find that at least ∼30% of cirrus in the TTL are definitely of convective origin.
Representations of quantum superalgebra U
q[gl(2|1)] in a coherent state basis and generalization
Authors: Kien Nguyen Cong , Ky Nguyen Anh , Nam Le Ba , Van Nguyen Thi Hong
Published: December 2011

The coherent state method has proved to be useful in quantum physics and mathematics. This method, more precisely, the vector coherent state method, has been used by some authors to construct representations of superalgebras but almost, to our knowledge, it has not yet been extended to quantum superalgebras, except Uq[osp(1|2)], one of the smallest quantum superalgebras. In this article the method is applied to a bigger quantum superalgebra, namely Uq[gl(2|1)], in constructing q–boson-fermion realizations and finite-dimensional representations which, when irreducible, are classified into typical and nontypical representations. This construction leads to a more general class of q–boson-fermion realizations and finite-dimensional representations of Uq[gl(2|1)] and, thus, at q = 1, of gl(2|1). Both gl(2|1) and Uq[gl(2|1)] have found different physics applications, therefore, it is meaningful to construct their representations.
Measurement of second hyperpolarizability components of a conjugated polymer
Authors: Yu Haibin , Deng Xiaoxu , Zhu Xiaohui , Li Honggen , Chen Xianfeng , Wei Wei , Liu Feng
Published: December 2011

A method has been proposed to determine the components of the second hyperpolarizability γ(-ω4;ω3,ω2,ω1) of a conjugated polymer in the off-resonant region based on the attenuated-total-reflection technique. By doing a least-square fit to the experimental data of γ(-ω;0,0,ω) for the quadratic electro-optic effect, the frequency-independent term of the components of γ(-ω4;ω3,ω2,ω1) is obtained, from which the components of γ(-ω4;ω3,ω2,ω1) are determined.
Relativistic many-electron calculations of Cr3+ L2,3-edge x ray absorption near-edge structures for Cr3+:α-Al2O3 and α-Cr2O3 and magnetic circular dichroism of Cr3+L2,3-edge x ray absorption near-edge structures for Cr3+:α-Al2O3
Authors: Watanabe Shinta , Nagasaki Takanori , Ogasawara Kazuyoshi
Published: December 2011

We performed first-principles calculations for Cr3+ L2,3-edge x ray absorption near-edge structures (XANES) of Cr3+:α-Al2O3 (ruby) and α-Cr2O3 and magnetic circular dichroism (MCD) of Cr3+ L2,3-edge XANES of ruby using a relativistic multielectron method. In order to investigate the lattice relaxation effects for ruby, theoretical studies were carried out using the three types of model clusters, including the lattice relaxation effects. These theoretical XANES spectra for both ruby and α-Cr2O3 well reproduced the experimental XANES spectra. The lattice relaxation effects on the XANES spectra for ruby were very small, while the results of configuration analysis of the many-electron wave function indicated that the mixing between L2 and L3 edges was significantly large in Cr3+ L2,3-edge XANES spectra for both ruby and α-Cr2O3. In addition, XANES spectra showed that the L3-edge component significantly mixed in the L2-edge peaks, while the L3-edge component also significantly contributed to the intensity of L2-edge. The theoretical MCD spectra for ruby also well reproduced the experimental one. We also investigated the validity of the sum rules quantitatively by comparing the magnetic moments calculated from the theoretical spectra using the sum rules and those calculated directly from the explicit many-electron wave functions. The orbital moments by both methods were almost zero, and the spin moments had 10% difference between these methods. The results of the configuration analysis indicated that the magnitude of the mixing between L2 and L3 edges could be the major cause of this discrepancy.