bluuebunny/crossref_metadata_2025 huggingface dataset:
Disability and risk of school related injury
Authors: Ramirez M , Peek-Asa C , Kraus J F
Published: February 2004

Objective:Approximately six million children with disabilities attend school in the United States. Cognitive and physical limitations may compromise their ability to handle environmental hazards and hence increase their risk for injury. The objective of this study was to describe the epidemiology of school related injury among children enrolled in 17 special education schools in one large, urban school district.

Design:Altogether 6769 schoolchildren with disabilities were followed up from 1994–98. Injury and population data were collected from pupil accident reports and existing school records. Associations were estimated through generalized estimating equations.

Results:A total of 697 injuries were reported for a rate of 4.7/100 students per year. Children with multiple disabilities had a 70% increased odds of injury compared with the developmentally disabled (odds ratio (OR) 1.7, 95% confidence interval (CI) 1.3 to 2.3). The physically disabled (OR 1.4, 95% CI 1.0 to 1.9) had a modest increased odds of injury. Cuts, bruises, and abrasions composed almost three fourths of all injuries; almost half of these injuries were to the face. Falls (34%) and insults by other students (31%) were the most common external causes. More than a fourth of injuries were sports related, and 21% occurred on the playground/athletic field. Injury patterns differed across disabilities.

Conclusions:Although limited to one school district, the population studied is the largest cohort thus far of schoolchildren with disabilities. With this large study base, potentially high risk groups were identified and circumstances of injury described. This information is imperative for developing and improving school based injury prevention measures.
Are older drivers actually at higher risk of involvement in collisions resulting in deaths or non-fatal injuries among their passengers and other road users?
Authors: Braver E R , Trempel R E
Published: February 2004

Objectives:With more older drivers on the road, public concern has been expressed about their impact on traffic safety. This study revisited the question of driver age in relation to the risks of older drivers and others sharing the road with them, including pedestrians, passengers in the same vehicle, and occupants of other vehicles.

Methods:Using United States federal data on fatal and non-fatal crashes, injury rates per driver were calculated for different types of road users. In addition, using data supplied by nine insurers, insurance claims per insured vehicle year were examined by driver age. The reference drivers were aged 30–59.

Results:For fatal crashes, older drivers’ major impact on road users other than themselves was an increase in death rates among their passengers, who also tended to be elderly and thus more vulnerable to injuries (rate ratio (RR) for drivers aged 75+ 2.52; 95% confidence interval (CI) 2.39 to 2.66). For non-fatal crashes, drivers aged 75+ had a RR of 1.10 (95% CI 0.98 to 1.24) for involvement in collisions resulting in injuries to other passenger vehicles’ occupants compared with 30–59 year old drivers. The oldest drivers (aged 85+) had significant increases in insurance claims for injuries to other road users in crashes in which they were deemed at fault (RR 1.8; 95% CI 1.71 to 1.89).

Conclusions:These findings suggest that the oldest drivers, a group with low average annual mileage, do pose some increased risks to occupants of other vehicles, and pose the most serious risks to themselves and their passengers.
A UNIQUENESS THEOREM OF THE 3-DIMENSIONAL ACOUSTIC SCATTERING PROBLEM IN A SHALLOW OCEAN WITH A FLUID-LIKE SEABED
Authors: GILBERT ROBERT P. , OU MIAO-JUNG
Published: February 2004

This paper shows that under the assumption of the out-going radiation conditions at infinity, the time-harmonic acoustic scattered field off a sound-soft solid in a shallow ocean with a fluid-like seabed is unique in [Formula: see text]. Here M1 is the water part, M2 the seabed, [Formula: see text] the waveguide and Ω the solid object. The associated modal problem is studied and a representation formula for the solution in terms of the Green's function is derived.
SYNCHRONOUS COOPERATIVE PARRONDO'S GAMES
Authors: MIHAILOVIĆ ZORAN , RAJKOVIĆ MILAN
Published: January 2004

Inspired by asynchronous cooperative Parrondo's games we introduce two new types of games in which all players simultaneously play game A or game B or a combination of these two games. These two types of games differ in the way a combination of games A and B is played. In the first type of synchronous games, all players simultaneously play the same game (either A or B), while in the second type players simultaneously play the game of their choice, i.e. A or B. We show that for these games, as in the case of asynchronous games, occurrence of the paradox depends on the number of players. An analytical result and an algorithm are derived for the probability distribution of these games.
MEASURING ELECTROCHEMICAL NOISE RESISTANCE FROM A WIRE BEAM ELECTRODE SURFACE FOR CORROSION RATE AND PATTERN DETERMINATION
Authors: TAN YONG-JUN
Published: January 2004

Electrochemical noise resistance (Rn), a new means of determining corrosion rates, has been considered to have only limited value since it offers little that cannot be achieved by conventional electrochemical methods. Aiming at overcome this limitation, a novel technique has been developed by combining the Rn method and an electrochemically-integrated electrode array namely the wire beam electrode (WBE). This combined Rn-WBE method effectively has extended the applicability of the Rn method from a uniform electrode surface to a nonuniform electrode surface. This present work is designed to examine the advantages and limitations of the Rn-WBE method in determining corrosion rates and patterns. The Rn-WBE method, together with other WBE based methods, was applied to corrosion systems of different characteristics. It was found that the Rn-WBE method has advantages over other WBE based methods when applying to a relatively uniform WBE surface. Both Rn-WBE method and the WBE based overpotential-galvanic current method were found to be similarly applicable to nonuniform WBE surfaces. However, the Rn-WBE method was found not applicable to low noise level corrosion systems. Some related issues regarding Rn calculation such as trend removal have also been clarified in this paper.
ELECTROCHEMICAL CURRENT OSCILLATIONS DURING LOCALIZED CORROSION OF IRON
Authors: SAZOU DIMITRA , PAGITSAS MICHAEL
Published: January 2004

In the present work the onset of current oscillations at late stages of iron pitting corrosion in chloride containing sulfuric acid solutions is further studied. By increasing the chloride concentration and potential, repassivation of iron becomes gradually unlikely giving rise to the formation of salt layers in front of the iron electrode and electropolishing processes. Occurrence of qualitative changes in electrochemical current oscillations as the chloride concentration and potential are varied is shown and discussed. Analysis of the transient behavior of current vs. time curves occurring before the establishment of a specific oscillatory pattern, reflect changes in the composition of salt layers in front of the electrode. At a critical potential value (bifurcation potential, E bif ) the system exhibits a transition from one type of oscillations (beating, aperiodic bursting) to another (chaotic oscillations of small amplitude). The temporal behavior of the system at potentials E < E bif is associated with a characteristic average time between bursts indicative of crisis-induced intermittency. In terms of physicochemical processes, the E bif coincides with the repassivation potential used in steady-state pitting corrosion studies to indicate different states of dissolution due to changes in the pit chemistry. Since the present system exhibits a non-steady passive-active transition state we suggest that E bif implies a transition from the electropolishing state dissolution to a passive-active state dissolution due to changes in the concentration of chloride and hydrogen ions inside pits.
ON THE STUDY OF ELECTROCHEMICAL TURBULENT NOISE IN A STIRRED VESSEL
Authors: MARTEMIANOV S. , DANAILA L.
Published: January 2004

Electrochemical measurements of turbulent fluctuations of limiting diffusion current have been performed in a stirred reactor, where an axisymmetric mean flow is produced using a small cylindrical impeller. We used an electrochemical probe with three electrodes: two small circular electrodes geometrically included in another circular, large electrode. The first small electrode was in the centre of the large electrode, the second small electrode was near the leading edge. An electrochemical reaction is carried out on the surface of the electrodes, under conditions that the reaction rate is fast enough and the concentration of the reacting species is zero at the probe surface. Three signals are simultaneously measured, when the probe is placed very close to the agitator extremity.

Spectral and wavelets analysis emphasize the presence of spikes for the three signals. There is significant evidence to indicate that a strong local energy concentration appears, at some particular frequencies. Further signal analysis is performed by calculating third-order and fourth-order structure functions (e.g. the skewness and flatness factors respectively). For each electrode, a different qualitative behaviour could be noted. This is an unexpected result for a "perfectly agitated" stirred reactor.
MODELING AND PARAMETRIC STUDY OF A FABRIC DRAPE
Authors: BRUNIAUX PASCAL , GHITH ADEL , VASSEUR CHRISTIAN
Published: January 2004

The objective of this study is to develop a fabric drape mathematical model in order to simulate the dynamic behavior of a textile structure. Simulation of fabric drape is a significant issue in textile research, which contributes to advances within the framework of virtual models and clothing simulation. In the first part of this paper, the existing methods dealing with the fabric simulation are presented. In the following part, a mathematical model that has been selected for simulation is given. The third part is devoted to the identification of unknown parameters. Each parameter corresponds to a predefined test. In order to obtain reliable results, very specific samples were realized, testing the fabric weave method and the influence of the yarn nature. This choice is guided by industrial needs. Moreover, the proposed method enables a sensitivity analysis of the model parameters. Finally, in the fourth part, several simulation results are presented and they are compared with practical results by analyzing textile structural deformation according to parameter variation.
A SYSTEM IDENTIFICATION APPROACH TO ESTIMATING COMPLEX IMPEDANCE SPECTRA FROM ELECTROCHEMICAL NOISE DATA
Authors: DE LEÓN GERARDO MIRAMONTES , FARDEN DAVID C. , McBRIDE LYLE E.
Published: January 2004

A system identification approach for the analysis of electrochemical noise data is proposed. The most common techniques, used by many investigators, are based on: (i) the ratio of sample standard deviations, which gives no information about the frequency dependence of the electrode impedance, or (ii) Power Spectral Density estimates, which deliver the modulus of the spectrum with large variations at the lowest frequencies. Phase is, almost invariably, not included. In this work, the electrochemical cell is modeled by an input-output model. With the application of system identification techniques, it is possible to identify values of the parameters of the system model. It is shown that this approach delivers a description of the system under study with: smooth electrode impedance curves, and magnitude and phase information. Some results obtained with the most common electrochemical noise analysis techniques are presented for comparison with the proposed approach. A theoretical limitation of the proposed approach appears if a perfect symmetry between both electrodes is considered.
COMPLEX SYSTEMS IN LANGUAGE EVOLUTION: THE CULTURAL EMERGENCE OF COMPOSITIONAL STRUCTURE
Authors: SMITH KENNY , BRIGHTON HENRY , KIRBY SIMON
Published: January 2004

Language arises from the interaction of three complex adaptive systems — biological evolution, learning, and culture. We focus here on cultural evolution, and present an Iterated Learning Model of the emergence of compositionality, a fundamental structural property of language. Our main result is to show that the poverty of the stimulus available to language learners leads to a pressure for linguistic structure. When there is a bottleneck on cultural transmission, only a language which is generalizable from sparse input data is stable. Language itself evolves on a cultural time-scale, and compositionality is language's adaptation to stimulus poverty.
COMMUNITY STRUCTURE IN JAZZ
Authors: GLEISER PABLO M. , DANON LEON
Published: January 2004

Using a database of jazz recordings we study the collaboration network of jazz musicians. We define the network at two different levels. First we study the collaboration network between individuals, where two musicians are connected if they have played in the same band. Then we consider the collaboration between bands, where two bands are connected if they have a musician in common. The community structure analysis reveals that these constructions capture essential ingredients of the social interactions between jazz musicians. We observe correlations between recording locations, racial segregation and the community structure. A quantitative analysis of the community size distribution reveals a surprising similarity with an e-mail based social network recently studied.
AN ASTROPHYSICAL BASIS FOR A UNIVERSAL ORIGIN OF LIFE
Authors: COLGATE STIRLING A. , RASMUSSEN STEEN , SOLEM JOHNDALE C. , LACKNER KLAUS
Published: January 2004

We propose a universal, astrophysically based theory of the origin of life on Earth and on other rocky planets as well. Life is an information system where the information content grows because of selection. It must start with the minimum possible information, or the minimum possible departure from thermodynamic equilibrium. It also requires thermodynamically free energy that is accessible by means of its information content. Hence, for its origin, we look for the most benign circumstance or minimum entropy variations over long times with abundant free energy. The unique location for this condition is the pore space in the first few kilometers of the earth's surface. The free energy is derived from the condensed products of the chemical reactions taking place in the cooling nebula e.g. iron oxides and fixed hydrocarbon, ( CH 2)16 and the benign environment is the thermal and radiation isolation of the earth's crust. We discuss how this environment occurs naturally and universally astrophysically. We then propose several chemical routes to the formation of life with a minimum entropy departure from thermodynamic equilibrium.
COUPLED GROWING NETWORKS
Authors: ZHENG DAFANG , ERGÜN GÜLER
Published: January 2004

We introduce and solve a model which considers two coupled networks growing simultaneously. The dynamics of the networks is governed by the new arrival of network elements (nodes) making preferential attachments to pre-existing nodes in both networks. The model segregates the links in the networks as intra-links, cross-links and mix-links. The corresponding degree distributions of these links are found to be power-laws with exponents having coupled parameters for intra- and cross-links. In the weak coupling case, the model reduces to a simple citation network. As for the strong coupling, it mimics the mechanism of the web of human sexual contacts.
DECISION SPREAD IN THE CORPORATE BOARD NETWORK
Authors: BATTISTON STEFANO , WEISBUCH GÉRARD , BONABEAU ERIC
Published: January 2004

The boards of large corporations sharing some of their directors are connected in complex networks. Boards are responsible for corporations' long-term strategy and are often involved in decisions about a common topic related to the belief in economical growth or recession. We are interested in understanding under which conditions a large majority of boards making the same decision can emerge in the network. We present a model where board directors are engaged in a decision-making dynamics based on "herd behavior." Boards influence each other through shared directors. We find that imitation of colleagues and opinion bias due to the interlock do not trigger an avalanche of identical decisions over the board network, whereas the information about interlocked boards' decisions does. There is no need to invoke global public information, nor external driving forces. This model provides a simple endogenous mechanism to explain the fact that boards of the largest corporations of a country can, in the span of a few months, make the same decisions about general topics.
Pyruvate and citric acid cycle carbon requirements in isolated skeletal muscle mitochondria
Authors: Messer Jeffrey I. , Jackman Matthew R. , Willis Wayne T.
Published: February 2004

Carbohydrate depletion precipitates fatigue in skeletal muscle, but, because pyruvate provides both acetyl-CoA for mainline oxidation and anaplerotic carbon to the citric acid cycle (CAC), the mechanism remains obscure. Thus pyruvate and CAC kinetic parameters were independently quantified in mitochondria isolated from rat mixed skeletal muscle. Mitochondrial oxygen consumption rate ( Jo) was measured polarographically while either pyruvate or malate was added stepwise in the presence of a saturating concentration of the other substrate. These substrate titrations were carried out across a physiological range of fixed extramitochondrial ATP free energy states (ΔGP), established with a creatine kinase energy clamp, and also at saturating [ADP]. The apparent Km,malate for mitochondrial Jo ranged from 21 to 32 μM, and the apparent Km,pyruvate ranged from 12 to 26 μM, with both substrate Km values increasing as ΔGP declined. Vmax for both substrates also increased as ΔGP fell, reflecting thermodynamic control of Jo. Reported in vivo skeletal muscle [malate] are >10-fold greater than the Km,malate determined in this study. In marked contrast, the Km,pyruvate determined is near the [pyruvate] reported in muscle approaching exhaustion associated with glycogen depletion. When data were evaluated in the context of a linear thermodynamic force-flow (ΔGP- Jo) relationship, the ΔGP- Jo slope was essentially insensitive to changes in [malate] in the range observed in vivo but decreased markedly with declining [pyruvate] across the physiological range. Mitochondrial respiration is particularly sensitive to variations in [pyruvate] in the physiological range. In contrast, physiological [malate] exerts very little, if any, influence on mitochondrial pyruvate oxidation measured in vitro.
The mTOR/p70 S6K1 pathway regulates vascular smooth muscle cell differentiation
Authors: Martin Kathleen A. , Rzucidlo Eva M. , Merenick Bethany L. , Fingar Diane C. , Brown David J. , Wagner Robert J. , Powell Richard J.
Published: February 2004

Vascular smooth muscle cells (VSMC) in mature, normal blood vessels exhibit a differentiated, quiescent, contractile morphology, but injury induces a phenotypic modulation toward a proliferative, dedifferentiated, migratory phenotype with upregulated extracellular matrix protein synthesis (synthetic phenotype), which contributes to intimal hyperplasia. The mTOR (the mammalian target of rapamycin) pathway inhibitor rapamycin inhibits intimal hyperplasia in animal models and in human clinical trials. We report that rapamycin treatment induces differentiation in cultured synthetic phenotype VSMC from multiple species. VSMC treated with rapamycin assumed a contractile morphology, quantitatively reflected by a 67% decrease in cell area. Total protein and collagen synthesis were also inhibited by rapamycin. Rapamycin induced expression of the VSMC differentiation marker contractile proteins smooth muscle (SM) α-actin, calponin, and SM myosin heavy chain (SM-MHC), as observed by immunoblotting and immunohistochemistry. Notably, we detected a striking rapamycin induction of calponin and SM-MHC mRNA, suggesting a role for mTOR in transcriptional control of VSMC gene expression. Rapamycin also induced expression of the cyclin-dependent kinase inhibitors p21cip and p27kip, consistent with cell cycle withdrawal. Rapamycin inhibits mTOR, a signaling protein that regulates protein synthesis effectors, including p70 S6K1. Overexpression of p70 S6K1 inhibited rapamycin-induced contractile protein and p21cip expression, suggesting that this kinase opposes VSMC differentiation. In conclusion, we report that regulation of VSMC differentiation is a novel function of the rapamycin-sensitive mTOR signaling pathway.
Evidence for functional estrogen receptors α and β in human adipose cells: regional specificities and regulation by estrogens
Authors: Dieudonné M. N. , Leneveu M. C. , Giudicelli Y. , Pecquery R.
Published: February 2004

Adipocytes are estrogen-responsive cells, but the quantitative expression and transcriptional regulation of the estrogen receptors (ER-α and ER-β) in human adipocytes and their precursor cells are unclear. Using real-time quantitative PCR, we have demonstrated that both ER-α and ER-β mRNA are expressed in human mature adipocytes with a large predominance of ER-α mRNA. Moreover, ER-α mRNA is identically expressed whatever the anatomic origin (intraabdominal and subcutaneous) of the adipocytes and the gender. ER-β mRNA levels are higher in women compared with men, without regional differences. 17β-Estradiol in vitro upregulates expression of both ER-α and ER-β mRNA in subcutaneous adipocytes from women but only the ER-α mRNA in subcutaneous and intra-abdominal adipocytes from men. In preadipocytes, only the ER-α subtype was present. In the latter cells, estrogens in vitro had no influence on ER-α expression (mRNA and protein). The present study also shows that estrogens in vitro increase the AP-1, SP-1, and estrogen response element DNA binding activities in differentiated but not in confluent preadipocytes, suggesting that ER become functional during the course of adipogenesis. On the whole, these data are consistent with a predominant role of the ER-α subtype in mediating the effects of estrogens on human adipose tissue development and metabolism.
Osmoregulation of vasopressin release and gene transcription under acute and chronic hypovolemia in rats
Authors: Kondo Noriko , Arima Hiroshi , Banno Ryouichi , Kuwahara Shinobu , Sato Ikuko , Oiso Yutaka
Published: February 2004

Although acute decreases in plasma volume are known to enhance the osmotically induced arginine vasopressin (AVP) release, it is unclear whether there is also such interaction at the level of gene transcription. It also remains to be established how sustained changes in plasma volume affect the osmoregulation. In this study, we examined how acute and chronic decreases in blood volume affected the osmoregulation of AVP release and gene transcription in rats. Acute hypovolemia was induced by intraperitoneal injection of polyethylene glycol (PEG), and chronic hypovolemia was induced by 3 days of water deprivation (WD) or 12 days of salt loading (SL). Rats were injected with isotonic or hypertonic saline, and plasma AVP levels and AVP heteronuclear (hn)RNA expression in the supraoptic and paraventricular nuclei, an indicator of gene transcription, were examined in relation to plasma osmolality in each group. Plasma AVP levels were correlated with plasma Na levels in all groups. Whereas the regression lines relating plasma AVP to Na were almost identical among control, WD, and SL groups, the thresholds of plasma Na for AVP release were significantly decreased only in the PEG group. AVP hnRNA levels were also correlated with plasma Na levels in control and PEG groups, and the thresholds were significantly decreased in the PEG group. In contrast, there was no significant correlation of AVP hnRNA and plasma Na levels in WD and SL groups. Thus it was demonstrated that acute and chronic reduction in plasma volume affected the osmoregulation of AVP release and gene transcription in different ways.
Forearm vascular control during acute hyperglycemia in healthy humans
Authors: Reed Ann S. , Charkoudian Nisha , Vella Adrian , Shah Pankaj , Rizza Robert A. , Joyner Michael J.
Published: February 2004

The vascular endothelium is a site of pathological changes in patients with diabetes mellitus that may be related to severe chronic hyperglycemia. However, it is unclear whether transient hyperglycemia alters vascular function in an otherwise healthy human forearm. To test the hypothesis that acute, moderate hyperglycemia impairs endothelium-dependent forearm vasodilation, we measured vasodilator responses in 25 healthy volunteers (11 F, 14 M) assigned to one of three protocols. In protocol 1, glucose was varied to mimic a postprandial pattern (i.e., peak glucose ∼11.1 mmol/l) commonly observed in individuals with impaired glucose tolerance. Protocol 2 involved 6 h of mild hyperglycemia (∼7 mmol/l). Protocol 3 involved 6 h of euglycemia. Glucose concentration was maintained with a variable systemic glucose infusion. Insulin concentrations were maintained at ∼65 pmol/l by means of a somatostatin and “basal” insulin infusion. Glucagon and growth hormone were replaced at basal concentrations. Forearm blood flow (FBF) was calculated from Doppler ultrasound measurements at the brachial artery. In each protocol, FBF dose responses to intrabrachial acetylcholine (ACh) and sodium nitroprusside (NTP) were assessed at baseline and at 60, 180, and 360 min of glucose infusion. Peak endothelium-dependent vasodilator responses to ACh were not diminished by hyperglycemia in any trial. For example, peak responses to ACh during protocol 2 were 307 ± 47 ml/min at euglycemic baseline and 325 ± 52, 353 ± 65, and 370 ± 70 ml/min during three subsequent hyperglycemic trials ( P = 0.46). Peak endothelium-independent responses to NTP infusion were also unaffected. We conclude that acute, moderate hyperglycemia does not cause short-term impairment of endothelial function in the healthy human forearm.
Bovine mammary gene expression profiling using a cDNA microarray enhanced for mammary-specific transcripts
Authors: Suchyta Steven P. , Sipkovsky Sue , Halgren Robert G. , Kruska Rachael , Elftman Michael , Weber-Nielsen Miriam , Vandehaar Michael J. , Xiao Lan , Tempelman Robert J. , Coussens Paul M.
Published: February 2004

A cDNA microarray resource enhanced for transcripts specific to the bovine mammary gland (BMAM) has been developed and used in pilot studies to examine gene expression profiles in the mammary gland. One goal driving development of this resource was to shed some light on the pathways and mechanisms specifically related to bovine mammary gland growth and development. To accomplish this, gene expression patterns from bovine adipose, liver, adrenal, lymph, spleen, thymus, gut, and developing mammary tissue were compared using the BMAM microarray. We have thus identified a putative set of 16 genes being preferentially expressed in developing mammary gland. Another of our long-term goals is to elucidate the genes and pathways associated with bovine lactation and involution and to use these as a model for human mammary gland development as it relates to human breast cancer risks. To begin this process, we conducted a pilot study, comparing gene expression profiles of lactating bovine mammary tissue against nonlactating tissue on the BMAM microarray. Our results have yielded many novel and interesting genes exhibiting differential expression in lactating mammary tissue, including oncogenes (VAV3, C-myc), mediators of apoptosis (Caspase 8), and cell cycle regulators (LASP1).
Genetic interaction between a maternal factor and the zygotic genome controls the intestine length in PRM/Alf mice
Authors: Aubin-Houzelstein Geneviève , Da Silva Nelly R. , Bellier Sylvain , Salaün Pierrick , Montagutelli Xavier , Panthier Jean-Jacques
Published: February 2004

Postoperative management of small and large bowel resections would be helped by use of intestinotrophic molecules. Here, we present a mouse inbred strain called PRM/Alf that is characterized by a selective intestinal lengthening. We show that PRM/Alf intestine is one-third longer compared with other inbred strains. The phenotype is acquired mostly during the postnatal period, before weaning. Its genetic determinism is polygenic, and involves a strong maternal effect. Cross-fostering experiments revealed that the dam’s genotype acts synergistically with the offspring’s genotype to confer the longest intestine. Moreover, genes in the offspring have a direct effect on intestine length. Possible involvement of milk growth factors and identification of candidate genes are discussed.
Murine Cytomegalovirus Infection Increases Aortic Expression of Proatherosclerotic Genes
Authors: Burnett Mary Susan , Durrani Sarfraz , Stabile Eugenio , Saji Motoyasu , Lee Cheol W. , Kinnaird Tim D. , Hoffman Eric P. , Epstein Stephen E.
Published: February 2004

Background—

The possible etiologic role of infection in cardiovascular disease is still debated. Having previously demonstrated that murine cytomegalovirus (MCMV) infection of apolipoprotein (apo) E
−/−
mice increases atherosclerotic lesion size, we determined if MCMV infection produces proatherogenic changes in aortic gene expression. Additionally, in cholesterol-fed C57BL/6J mice, we examined the effects of MCMV infection on aortic lesion area.

Methods and Results—

C57BL/6J apoE
−/−
and wild-type C57BL/6J mice were infected with MCMV. At various time points, aortas were collected and pooled. Total RNA was extracted and hybridized to Affymetrix murine chips or analyzed for specific gene expression using TaqMan reverse transcription–polymerase chain reaction. Data from infected and uninfected mice were compared. A separate group of cholesterol-fed C57BL/6J mice were infected with MCMV, and lesion area in the aortic sinus was assessed using oil red O staining. Acute MCMV infection altered aortic expression of atherogenic genes in young apoE
−/−
and C57BL/6J mice—specifically, monocyte chemoattractant protein-1, monokine induced by interferon-γ, and interferon-γ inducible protein 10. Acute infection in adult 9-month-old apoE
−/−
mice with well-established lesions increased aortic expression of monocyte chemoattractant protein-1. Atherosclerotic lesion area in cholesterol-fed C57BL/6J mice was increased after infection with MCMV.

Conclusions—

MCMV infection significantly increases atherosclerotic lesion area and aortic expression of atherogenic genes. These infection-induced effects indicate mechanisms by which cytomegalovirus may contribute to atherosclerotic disease initiation and progression and to the precipitation of clinical events. These results additionally add to data compatible with the concept that infection does play an important role in atherosclerotic disease.
Pulse Pressure Is an Independent Predictor for the Progression of Aortic Wall Calcification in Patients With Controlled Hyperlipidemia
Authors: Miwa Yoshikazu , Tsushima Motoo , Arima Hisatomi , Kawano Yuhei , Sasaguri Toshiyuki
Published: February 2004

Recent epidemiological studies suggested that calcifications of the aorta and the coronary arteries are important predictors for cardiovascular morbidity and mortality. However, the relation between blood pressure components and the progression of vascular wall calcification has remained unclear. We quantified calcium deposits in the abdominal aorta as the percentage of aortic calcification volume (%ACV) using computed tomography in patients with hyperlipidemia. Those who had aortic calcification were treated with lipid-lowering agents and followed-up for >2 years (6.3±3.2 years). The relationship between the components of blood pressure and the increase in %ACV per year (Δ%ACV/year) was assessed in subjects in whom serum lipid levels were well controlled during the follow-up periods. An age- and sex-adjusted correlation analysis showed that Δ%ACV/year was significantly correlated to body mass index (
r
=0.229,
P
=0.015), systolic blood pressure (
r
=0.244,
P
=0.009), and pulse pressure (
r
=0.359,
P
<0.001). A multivariate regression analysis revealed that pulse pressure is an independent and the most sensitive predictor for Δ%ACV/year (β=0.389,
P
<0.001) among the blood pressure components. These results suggested that increase in pulse pressure promotes the progression of vascular calcification.
Traveltime calculation and prestack depth migration in tilted transversely isotropic media
Authors: Kumar Dhananjay , Sen Mrinal K. , Ferguson Robert J.
Published: January 2004

The principal objective of our work is to develop a technique for prestack depth migration in tilted transversely isotropic (TTI) media in which the axis of symmetry is not vertical and may be spatially varying. Such models are required to image seismic data in geologically complex regions such as the Canadian Foothills. We have developed a 2D Kirchhoff integral‐based migration algorithm in which the traveltime computation comprises the major task. Among the existing traveltime computation algorithms such as ray tracing with interpolation, ray bending, and eikonal solvers, a direct or a brute force approach of traveltime computation is generally highly robust. We have modified a direct method of first‐arrival P‐wave traveltime computation in 2D media that accounts for TTI. The algorithm requires that the group velocity be computed at each gridpoint, using either an analytic solution or by an approximate Fourier series expansion. The P‐wave traveltime contours computed for complex geologic models show the pronounced effects from TTI media. Our results, using laboratory P‐wave data collected over a physical model of an anisotropic thrust sheet, reveal that a 2D Kirchhoff migration based on our traveltime algorithm (TTI model) images the structure beneath the thrust sheet very well. The vertical transversely isotropic (assuming a vertical axis of symmetry) or isotropic imaging introduces false anticlinal structures. We compare our results with those obtained by a recursive‐extrapolation method and find that our approach images the underside of one of the thrust sheets better.
Inversion of magnetotelluric data for 2D structure with sharp resistivity contrasts
Authors: de Groot‐Hedlin Catherine , Constable Steven
Published: January 2004

We have developed a linearized algorithm to invert noisy 2‐D magnetotelluric data for subsurface conductivity structures represented by smooth boundaries defining sharp resistivity contrasts. We solve for both a fixed number of subsurface resistivities and for the boundary locations between adjacent units. The boundary depths are forced to be discrete values defined by the mesh used in the forward modeling code. The algorithm employs a Lagrange multiplier approach in a manner similar to the widely used Occam method. The main difference is that we penalize variations in the boundary depths, rather than in resistivity contrasts between a large number of adjacent blocks. To reduce instabilities resulting from the breakdown of the linear approximation, we allow an option to penalize contrasts in the resistivities of adjacent units.

We compare this boundary inversion method to the smooth Occam inversion for two synthetic models, one that includes a conductive wedge between two resistors and another that includes a resistive wedge between two conductors. The two methods give good agreement for the conductive wedge, but the solutions differ for the more poorly resolved resistive wedge, with the boundary inversion method giving a more geologically realistic result. Application of the boundary inversion method to the resistive Gemini subsalt petroleum prospect in the Gulf of Mexico indicates that the shape of this salt feature is accurately imaged by this method, and that the method remains stable when applied to real data.
Relative performance of moveout‐based multiple‐suppression methods for amplitude variation with offset (AVO) analysis and common midpoint (CMP) stacking
Authors: Alvarez Gabriel , Larner Ken
Published: January 2004

We apply three moveout‐based methods for multiple suppression to simple synthetic common midpoint (CMP) gathers and compare their performance in terms of level of multiple rejection and, more importantly, in terms of (1) suitability of processed output for use in analysis of amplitude variations with offset (AVO), (2) primary‐to‐multiple amplitude (p/m) ratio of the data after CMP stacking, and (3) preservation of primary wavelet shape and amplitude on the stack. The three approaches are filtering in the frequency–wavenumber f–k domain, the Hampson method of filtering in the parabolic Radon transform domain, and a hybrid method that improves upon Hampson's approach by using a variation of Harlan's statistical pattern recognition approach to separate primaries from multiples in the parabolic Radon transform domain.

The f–k approach is unsuitable prior to AVO analysis; moreover, it is little better in suppressing the multiples than the CMP stack itself. Hampson's method performs considerably better and is suitable for both purposes, although it can yield distorted AVO response where multiples are relatively strong on input. At about 50% additional computation effort over that of Hampson's method, the hybrid approach has superior treatment of amplitude behavior with offset. For many situations, the hybrid method yields up to twice the primary‐to‐multiples amplitude ratio on the CMP stack.
Voriconazole in Fungal Keratitis Caused by Scedosporium apiospermum
Authors: Prats Hernández Carmen , Tello Francisca Llinares , José Amparo Burgos San , Otaolaurruchi Juan Selva , Baines Juan Pablo Ordovás
Published: February 2004

OBJECTIVE

To describe the first case, to the best of our knowledge, of posttraumatic Scedosporium apiospermum (ScA) keratitis successfully treated with systemic and topical voriconazole.

CASE SUMMARY

A 19-year-old man was admitted to the hospital with an incisive wound of his left eye and the cornea totally sectioned after trauma with a cutter used in gardening. Initial empirical treatment was followed by systemic and topical voriconazole, and the eye did not have to be enucleated. Five months after the trauma, a penetrating keratoplasty and chamber intraocular lens implantation was performed with a favorable visual outcome.

DISCUSSION

ScA keratitis is rare, but it must be suspected if a history of ocular injury with contaminated objects exists. Among the antifungals available to treat ScA keratitis, voriconazole has shown advantages such as the lowest minimum inhibitory concentration and the availability of an oral formulation.

CONCLUSION

Voriconazole shows promise as an effective alternative to conventional antifungals in the treatment of ScA keratitis. It is available both as oral and intravenous preparations, which is a great advantage in these lengthy infections.
Immunopeptidometric Assay for Enzymatically Active Prostate-Specific Antigen
Authors: Wu Ping , Zhu Lei , Stenman Ulf-Håkan , Leinonen Jari
Published: February 2004

Background: Determinations of certain forms of prostate-specific antigen (PSA) have been shown to increase the specificity for prostate cancer (PCa). One such variant, proteolytically active PSA, is a potentially useful tumor marker, but it is not specifically recognized by antibodies. Using phage display libraries, we previously identified a “family” of peptides that bind specifically to active PSA. We used these to develop an immunopeptidometric assay (IPMA) that specifically detects this form of PSA.

Methods: Microtitration plates coated with a PSA antibody were used to capture PSA, and a PSA-binding glutathione S-transferase (GST) fusion peptide was used as a tracer. Bound tracer was detected with an antibody to GST labeled with a europium chelate. PSA isoenzymes with high and low enzymatic activity were used to study binding specificity.

Results: The IPMA detected enzymatically active PSA but not internally cleaved PSA and pro-PSA, which are enzymatically inactive. The assay detected 1–10% of free PSA in serum from PCa patients.

Conclusions: Peptides identified by phage display can be used to develop assays with unique specificities for enzymatically active PSA. IPMA represents a new assay principle with wide potential utility.
High-Level Multiplex Genotyping of Polymorphisms Involved in Folate or Homocysteine Metabolism by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry
Authors: Meyer Klaus , Fredriksen Åse , Ueland Per Magne
Published: February 2004

Background: Increased plasma total homocysteine (tHcy), a risk factor for cardiovascular disease, is related to genetic, environmental, and nutritional factors, in particular folate status. Future large epidemiologic studies of the genetic basis of hyperhomocysteinemia will require high-throughput assays for polymorphisms of genes related to folate and Hcy metabolism.

Method: We developed a high-level multiplex genotyping method based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the detection of 12 polymorphisms in 8 genes involved in folate or Hcy metabolism. The assay includes methylenetetrahydrofolate reductase (MTHFR) 677C>T and 1298A>C, methionine synthase (MTR) 2756A>G, methionine synthase reductase (MTRR) 66A>G, cystathionine β-synthase (CBS) 844ins68 and 699C>T, transcobalamin II (TCII) 776C>G and 67A>G, reduced folate carrier-1 (RFC1) 80G>A, paraoxonase-1 (PON1) 575A>G and 163T>A, and betaine homocysteine methyltransferase (BHMT) 742G>A.

Results: The failure rate of the assay was ≤1.7% and was attributable to unsuccessful DNA purification, nanoliter dispensing, and spectrum calibration. Most errors were related to identification of heterozygotes as homozygotes. The mean error rate was 0.26%, and error rates differed for the various single-nucleotide polymorphisms. Identification of CBS 844ins68 was carried out by a semiquantitative approach. The throughput of the MALDI-TOF MS assay was 1152 genotypes within 20 min.

Conclusions: This high-level multiplex method is able to genotype 12 polymorphisms involved in folate or Hcy metabolism. The method is rapid and reproducible and could facilitate large-scale studies of the genetic basis of hyperhomocysteinemia and associated pathologies.
Evaluation of an intervention program for the reduction of bullying and victimization in schools
Authors: Baldry Anna C. , Farrington David P.
Published: January 2004

The present study evaluates the effect of an intervention program on the reduction of bullying and victimization in schools with a sample of 239 students aged 10–16 years old in Rome, Italy. The program deals with bullying and violence. It consists of three videos and a booklet that help students to develop the social cognitive competence skills to understand the negative consequences of aggressive behavior. The intervention was evaluated using an experimental design with pre‐test and post‐test analyses. Students were randomly allocated to experimental or control classes. Students completed a self‐report questionnaire in which they were asked to indicate on a 5–point scale how often they were victimized or bullied others. Victimization and bullying were assessed by using questions about specific types of actions, a composite measure of victimization and bullying, and a single question about victimization and bullying in general. Results showed that the program worked best for older students, but not for younger ones who in some cases reported an increased level of victimization after the intervention. For older students there was a decrease in victimization according to the sum of types of behavior for the experimental group, but an increase for the control group. The same result was found for direct victimization, having belongings stolen, and being called nasty names. Therefore, the program seemed to be beneficial for older students but possibly damaging for younger students. It is suggested that the program could have worked better with older students because of the cognitive skills it required. Younger students could have reported higher levels of bullying after the intervention because they became more sensitized to the topic of bullying. Aggr. Behav. 30:1–15, 2004. © 2004 Wiley‐Liss, Inc.
Does perpetrator punishment satisfy victims' feelings of revenge?
Authors: Orth Ulrich
Published: January 2004

Criminal victimization often provokes strong feelings of revenge. Two studies were conducted to investigate whether legal punishment of the perpetrator reduces victims' feelings of revenge. A cross‐sectional study of 174 crime victims revealed that punishment severity does not predict feelings of revenge at a time several years after the trial. A longitudinal study of 31 crime victims revealed that, for the time interval from a few weeks before the trial to a few weeks after the trial, punishment severity significantly predicts a decrease in feelings of revenge; nevertheless intraindividual and interindividual stability of these feelings was high. Taken together, results of the two studies suggest that perpetrator punishment only partially, and moreover only transitorily, satisfies victims' feelings of revenge. Therefore, satisfaction of victims' feelings of revenge cannot be taken as empirical justification for tightening of sentencing norms. Aggr. Behav. 30:62–70, 2004. © 2004 Wiley‐Liss, Inc.
Association between measures of aggression and bullying among juvenile and young offenders
Authors: Ireland Jane L. , Archer John
Published: January 2004

This study addresses the relationship between aggression and behaviors indicative of bullying in a sample of incarcerated male juvenile and young offenders. The study also addresses whether or not offenders who bully others and/or are bullied themselves can be identified by the type of aggression that they report. Ninety‐five juvenile and 196 young offenders completed a self‐report behavioral checklist (DIPC: Direct and Indirect Prisoner Behavior Checklist) that addressed their experience of and involvement in behaviors indicative of bullying. They also completed the Aggression Questionnaire (AQ), a measure of physical and verbal aggression, anger and hostility. Four categories of offenders were identified from the DIPC ‐ pure bullies, pure victims, those who were both bullies and victims (bully/victims), and those not‐involved in bullying behavior. As predicted, behaviors measured on the DIPC that were indicative of ‘bullying others’ correlated positively with scores on the AQ. There was no indication, however, that physical AQ and physical bullying on the DIPC were the same constructs. There was a closer association between verbal AQ scores and verbal bullying on the DIPC. Bullies and bully/victims reported higher levels of physical and verbal aggression, and bully/victims reported higher levels of hostility and anger, than the other categories. It is concluded that although there are similarities between the AQ and the DIPC, there is no evidence that they are measuring the same type of aggression, although different groups involved in bullying can be partly distinguished by their scores on the AQ. Aggr. Behav. 30:29–42, 2004. © 2004 Wiley‐Liss, Inc.