bluuebunny/crossref_metadata_2025 huggingface dataset:
Effets de la coupe à blanc et de la coupe par bandes sur la régénération obtenue après 5 ans dans des pessières noires du Québec
Authors: Pominville Pierre , Ruel Jean-Claude
Published: March 2008

An experiment was conducted to compare the effects of traditional clear-cutting with those of strip cutting on regeneration of black spruce, Piceamariana (Mill.) B.S.P., stands on scarified and unscarified uplands and on lowlands. To that effect, regeneration surveys were done before cutting, in the following year, and 3 and 5 years after cutting. Five years after harvesting, strip cutting led to higher coniferous stocking than clear-cutting on scarified uplands and on lowlands. On unscarified uplands, the gain attributable to strip cutting was not significant. The coniferous stocking of strip cuts on scarified uplands was not greater than on unscarified uplands. So the efficiency of scarification could not be proved in that study. Stocking obtained after 5 years remained closely related to the one observed immediately after harvesting in the strip cufs as in the clear-cuttings. This is particularly true for balsam fir, Abiesbalsamea (L.) Mill. In the strip cuts, the balsam fir stocking was constant while the one of black spruce increased. This could have an impact on the evolution of the composition of the new stands and, consequently, on their vulnerability to spruce budworm, Choristoneurafumiferana (Clem.). The majority of the clear-cuttings were well regenerated 5 years after harvesting. Their average coniferous stocking was slightly above 60%. However, 48% of the clear-cuttings did not reach this level when only unscarified plots on uplands were considered. Advance growth was abundant in those plots but suffered high losses during harvesting. Consequently, reducing the losses during harvesting would result in a lower proportion of clear-cuttings with insufficient coniferous stocking 5 years after cutting. On the other hand, almost all the strip cuts with insufficient regeneration after harvesting were well regenerated 5 years later. Thus, strip cutting could be an interesting option on sites with insufficient advance growth and on sites well regenerated before cutting but where important losses during harvesting are anticipated.
A technique for estimating below-stump biomass of mature loblolly pine plantations
Authors: Kapeluck P.R. , Lear D.H. Van
Published: March 2008

A technique was developed for estimating below-stump biomass of mature loblolly pine (Pinustaeda L.). The technique required complete excavation of only three trees and partial excavation (taproot only) of 12 others. A regression methodology for roots > 0.6 cm diameter and traditional soil-core sampling for roots < 0.6 cm diameter formed the main elements of the technique. Strong relationships were found (1) between biomass of three diameter classes of lateral roots and their proximal end diameter and (2) between diameter at breast height and estimated below-stump biomass for roots > 0.6 cm diameter. This technique should be useful for estimating root biomass of plantations of loblolly pine and may be effective for large trees of other species.
RECONSTRUCTING DYNAMICS FROM OBSERVABLES: THE ISSUE OF THE DELAY PARAMETER REVISITED
Authors: TSONIS ANASTASIOS A.
Published: March 2008

In this tutorial/review we revisit the problem of choosing a proper delay when we reconstruct attractors. The effect of this delay is investigated thoroughly and a definite answer to this problem as well as a robust procedure to reconstruct attractors is presented.
DYNAMICS OF A HYPERCHAOTIC LORENZ SYSTEM
Authors: BARBOZA RUY
Published: March 2008

In this paper, we investigate the dynamics of the Lorenz system, linearly extended into one additional dimension. The system is hyperchaotic in a wide range of parameters. A theoretical and numerical study indicates that chaos and hyperchaos are produced with the help of a van der Pol-like oscillatory motion around a hypersaddle stationary point at the origin. Numerical experiments are presented, showing Lyapunov exponents, bifurcation diagrams and Poincaré sections.
ACTIVE CONTROL AND GLOBAL SYNCHRONIZATION OF THE COMPLEX CHEN AND LÜ SYSTEMS
Authors: MAHMOUD GAMAL M. , BOUNTIS TASSOS , MAHMOUD EMAD E.
Published: March 2008

Chaos synchronization is a very important nonlinear phenomenon, which has been studied to date extensively on dynamical systems described by real variables. There also exist, however, interesting cases of dynamical systems, where the main variables participating in the dynamics are complex, for example, when amplitudes of electromagnetic fields are involved. Another example is when chaos synchronization is used for communications, where doubling the number of variables may be used to increase the content and security of the transmitted information. It is also well-known that similar generalization of the Lorenz system to one with complex ODEs has been introduced to describe and simulate the physics of a detuned laser and thermal convection of liquid flows. In this paper, we study chaos synchronization by applying active control and Lyapunov function analysis to two such systems introduced by Chen and Lü. First we show that, written in terms of complex variables, these systems can have chaotic dynamics and exhibit strange attractors. We calculate numerically the values of the parameters at which these attractors exist. Active control and global synchronization techniques are then applied to study the phenomenon of chaos synchronization. Analytical criteria concerning the stability of these techniques are implemented and excellent agreement is found upon comparison with numerical experiments. In particular, studying the time evolution of "errors" (or differences between drive and control dynamics), we show that both techniques are very effective for controlling the behavior of these systems, even in regimes of very strong chaos.
WEAKLY CONNECTED OSCILLATORY NETWORK MODELS FOR ASSOCIATIVE AND DYNAMIC MEMORIES
Authors: CORINTO FERNANDO , BONNIN MICHELE , GILLI MARCO
Published: March 2008

Several studies in neuroscience have shown that nonlinear oscillatory networks represent bio-inspired models for information and image processing. Recent studies on the thalamo-cortical system have shown that weakly connected oscillatory networks (WCONs) exhibit associative properties and can be exploited for dynamic pattern recognition. In this manuscript we focus on WCONs, composed of oscillators that adhere to a Lur'e like description and are organized in such a way that they communicate one another, through a common medium. The main dynamic features are investigated by exploiting the phase deviation equation (i.e. the equation that describes the phase variation of each oscillator, due to weak coupling). Firstly a very accurate analytic expression of the phase deviation equation is derived, by jointly describing the function technique and the Malkin's Theorem. Furthermore, by using a simple learning algorithm, the phase-deviation equation is designed in such a way that given sets of patterns can be stored and recalled. In particular, two models of WCONs are presented as examples of associative and dynamic memories.
GALTON'S QUINCUNX: RANDOM WALK OR CHAOS?
Authors: JUDD KEVIN
Published: March 2008

In 1873 Francis Galton had constructed a simple mechanical device where a ball is dropped vertically through a harrow of pins that deflect the ball sideways as it falls. Galton called the device a quincunx, although today it is usually referred to as a Galton board. Statisticians often employ (conceptually, if not physically) the quincunx to illustrate random walks and the central limit theorem. In particular, how a Binomial or Gaussian distribution results from the accumulation of independent random events, that is, the collisions in the case of the quincunx. But how valid is the assumption of "independent random events" made by Galton and countless subsequent statisticians? This paper presents evidence that this assumption is almost certainly not valid and that the quincunx has the richer, more predictable qualities of a low-dimensional deterministic dynamical system. To put this observation into a wider context, the result illustrates that statistical modeling assumptions can obscure more informative dynamics. When such dynamical models are employed they will yield better predictions and forecasts.
INCREASING THE ENTROPY OF A RANDOM NUMBER GENERATOR USING n-SCROLL CHAOTIC ATTRACTORS
Authors: YALÇIN M. E.
Published: March 2008

The purpose of this paper is to investigate the effect of the number of scrolls on the measure-theoretic entropy of a random bit generator (RBG) based on multiscroll chaotic attractor. The binary output of the proposed RBG is obtained by sampling the output of the generalized nonlinearity of multiscroll chaotic attractor circuit which is in fact a noninvertible function. Our numeric simulations show that the entropy of the proposed random bit generator is increased by increasing the number of scrolls.
CRITICAL POINTS OF DISTANCE TO AN ε-SAMPLING OF A SURFACE AND FLOW-COMPLEX-BASED SURFACE RECONSTRUCTION
Authors: DEY TAMAL K. , GIESEN JOACHIM , RAMOS EDGAR A. , SADRI BARDIA
Published: March 2008

The distance function to surfaces in three dimensions plays a key role in many geometric modeling applications such as medial axis approximations, surface reconstructions, offset computations and feature extractions among others. In many cases, the distance function induced by the surface can be approximated by the distance function induced by a discrete sample of the surface. The critical points of the distance functions are known to be closely related to the topology of the sets inducing them. However, no earlier theoretical result has found a link between topological properties of a geometric object and critical points of the distance to a discrete sample of it. We provide this link by showing that the critical points of the distance function induced by a discrete sample of a surface fall into two disjoint classes: those that lie very close to the surface and those that are near its medial axis. This closeness is precisely quantified and is shown to depend on the sampling density. It turns out that critical points near the medial axis can be used to extract topological information about the sampled surface. Based on this, we provide a new flow-complex-based surface reconstruction algorithm that, given a tight ε-sample of a surface, approximates the surface geometrically, both in distance and normals, and captures its topology. Furthermore, we show that the same algorithm can be used for curve reconstruction.
Teaching the physiology of adaptation to hypoxic stress with the aid of a classic paper on high altitude by Houston and Riley
Authors: Tansey Etain A.
Published: March 2008

Many pathological conditions exist where tissues exhibit hypoxia or low oxygen tension. Hypoxic hypoxia arises when there is a reduction in the amount of oxygen entering the blood and occurs in healthy people at high altitude. In 1946, research sponsored by the United States Navy led to the collection and subsequent publication of masses of data demonstrating the physiological consequences and adaptations of ascent to high altitude. This article describes how a figure from a 1947 paper from the American Physiological Society Legacy collection (Houston CS, Riley RL. Respiratory and circulatory changes during acclimatization to high altitude. Am J Physiol 149: 565–588) may be used to allow students to review their understanding of some of the generalized effects of hypoxia on the body. In particular, this figure summarizes some of the adaptive responses that take place in the oxygen transport system as a consequence of prolonged hypoxia.
Beyond the printed page: physiology education without a textbook?
Authors: Stavrianeas Stasinos , Stewart Mark , Harmer Peter
Published: March 2008

Pedagogical innovations, ideas, and outcomes designed to enhance student learning in physiology courses are encouraged by our professional organizations and are actively discussed at conferences and in Advance in Physiological Education. Here, we report our experiment with freely available internet-based material as a substitute for the textbook for a single chapter on muscle physiology in a sophomore-level Human Physiology course. Student reactions to the textbookless curriculum were registered with the use of a questionnaire. Their responses indicated that they enjoyed the online material (animations, images, reviews, etc.), the emphasis on important concepts, and the variety of resources. Furthermore, students were almost unanimous in their praise for such pedagogical approaches to science education. Yet, students were reluctant to part with their textbooks. We believe that with subsequent iterations of this course we will be more successful at further separating the learning experience from the textbook. Reliance on freely available material may eventually relieve students from the burden of purchasing a costly textbook.
The journey of a sandwich: computer-based laboratory experiments about the human digestive system in high school biology teaching
Authors: Šorgo Andrej , Hajdinjak Zdravka , Briški Darko
Published: March 2008

Teaching high school students about the digestive system can be a challenge for a teacher when s/he wants to overcome rote learning of facts without a deeper understanding of the physiological processes inside the alimentary tract. A series of model experiments illustrating the journey of a sandwich was introduced into teaching high school biology. Using a computer equipped with a commercially available data-acquisition system and a couple of sensors, it was possible to illustrate the basic underlying physical and chemical principles of digestion to the students. Students were able to investigate, through hands-on activities, the chewing force of the jaws, importance of the mechanical breakdown of food, enzymatic activity of pepsin and amylase, antibacterial activity of hydrochloric acid, and importance of the villi for absorption. Students found the experiments interesting and helpful for understanding the digestive process. Furthermore, the results from testing indicated that the students had a deeper understanding of the physiological processes.
New ways of thinking about (and teaching about) intestinal epithelial function
Authors: Barrett Kim E.
Published: March 2008

This article summarizes a presentation made at the Teaching Refresher Course of the American Physiological Society, which was held at the Experimental Biology meeting in 2007. The intestinal epithelium has important ion transport and barrier functions that contribute pivotally to normal physiological functioning of the intestine and other body systems. These functions are also frequently the target of dysfunction that, in turn, results in specific digestive disease states, such as diarrheal illnesses. Three emerging concepts are discussed with respect to ion transport: the complex interplay of intracellular signals that both activate and inhibit chloride secretion; the role of multiprotein complexes in the regulation of ion transport, taking sodium/hydrogen exchange as an example; and acute and chronic regulation of colonic sodium absorption, involving both sodium channel internalization and de novo synthesis of new channels. Similarly, recently obtained information about the molecular components of epithelial tight junctions and the ways in which tight junctions are regulated both in health and disease are discussed to exemplify ways to teach about intestinal barrier properties. Finally, both genetically determined intestinal diseases and those arising as a result of infections and/or inflammation are described, and these can be used as the means to enhance the basic and clinical relevance of teaching about intestinal epithelial physiology as well as the impact that the understanding of such physiology has had on associated therapeutics. The article also indicates, where relevant, how different approaches may be used effectively to teach related concepts to graduate versus medical/professional student audiences.
Teaching pulmonary gas exchange physiology using computer modeling
Authors: Kapitan Kent S.
Published: March 2008

Students often have difficulty understanding the relationship of O2 consumption, CO2 production, cardiac output, and distribution of ventilation-perfusion ratios in the lung to the final arterial blood gas composition. To overcome this difficulty, I have developed an interactive computer simulation of pulmonary gas exchange that is web based and allows the student to vary multiple factors simultaneously and observe the final effect on the arterial blood gas composition (available at www.siumed.edu/medicine/pulm/vqmodeling.htm ). In this article, the underlying mathematics of the computer model is presented, as is the teaching strategy. The simulation is applied to a typical clinical case drawn from the intensive care unit to demonstrate the interdependence of the above factors as well as the less-appreciated importance of the Bohr and Haldane effects in clinical pulmonary medicine. The use of a computer to vary the many interacting factors involved in the arterial blood gas composition appeals to today's students and demonstrates the importance of basic physiology to the actual practice of medicine.
Variation in the 3-Hydroxyl-3-Methylglutaryl Coenzyme A Reductase Gene Is Associated With Racial Differences in Low-Density Lipoprotein Cholesterol Response to Simvastatin Treatment
Authors: Krauss Ronald M. , Mangravite Lara M. , Smith Joshua D. , Medina Marisa W. , Wang Dai , Guo Xiuqing , Rieder Mark J. , Simon Joel A. , Hulley Steven B. , Waters David , Saad Mohammed , Williams Paul T. , Taylor Kent D. , Yang Huiying , Nickerson Deborah A. , Rotter Jerome I.
Published: March 2008

Background—

Use of 3-hydroxyl-3-methylglutaryl-3 coenzyme A reductase (HMGCR) inhibitors, or statins, reduces cardiovascular disease risk by lowering plasma low-density lipoprotein cholesterol (LDL-C) concentrations. However, LDL-C response is variable and influenced by many factors, including racial ancestry, with attenuated response in blacks compared with whites. We hypothesized that single nucleotide polymorphisms in the gene encoding
HMGCR
, a rate-limiting enzyme in cholesterol synthesis and the direct enzymatic target of statins, contribute to variation in statin response.

Methods and Results—

Genomic resequencing of
HMGCR
in 24 blacks and 23 whites identified 79 single nucleotide polymorphisms. Eleven single nucleotide polymorphisms were selected to tag common linkage disequilibrium clusters. These single nucleotide polymorphisms and the common haplotypes inferred from them were tested for association with plasma LDL-C and LDL-C response to simvastatin treatment (40 mg/d for 6 weeks) in 326 blacks and 596 whites. Black carriers of H7 and/or H2 had significantly lower baseline LDL-C (
P
=0.0006) and significantly attenuated LDL-C response compared with black participants who did not carry either haplotype as measured by absolute response (−1.23±0.04 mmol/L, n=209, versus −1.45±0.06 mmol/L, n=117;
P
=0.0008) and percent response (−36.9±1.0% versus −40.6±1.3%;
P
=0.02), but no haplotype effect was observed in whites. Percent LDL-C response was lowest in carriers of both H2 and H7, all but one of whom were black (−28.2±4.9%, n=12 H2+H7 carriers, versus −41.5±0.5%, n=650 H2/H7 noncarriers;
P
=0.001). LDL-C responses in H7 and/or H2 noncarriers were indistinguishable between blacks and whites.

Conclusions—

HMGCR
gene polymorphisms are associated with reduced plasma LDL-C and LDL-C response to simvastatin, and these effects are most evident in blacks.
Consular Affairs in the EU: Visa Policy as a Catalyst for Integration?
Authors: Fernández Ana Mar
Published: March 2008

In recent years there has been increasing interest in the literature regarding the changes that European integration has meant for the external administration of the member states. This article seeks to contribute to this study through analysis of an area that has received little attention until now: the Europeanization of consular affairs in the field of visa issuance. The article analyses the common visa policy and discusses its consequences for member states' management of overseas consular affairs. The main conclusion reached is that this policy has been a catalyst for change in the working of consular services, which have become part of networks of intergovernmental cooperation and have been progressively informed by Community norms and procedures. However, it would be premature to say that this process of change is paving the way for the emergence of a European consular administrative sphere. For the moment, the integrated management of consular affairs in the field of visas continues to be a mainly state-controlled process.
Synthesis and Characterization of Srilankite Nanowires
Authors: Germain Marguerite , Fraundorf Philip , Lin Sam , Guliants Elena A. , Bunker Christopher E. , Buckner Steven W.
Published: March 2008

We describe the synthesis and characterization of srilankite (Ti2ZrO6) nanowires. The nanowires are produced via hydrothermal synthesis with a TiO2/ZrO2 mixture under alkaline conditions. The zirconium titanate nanowires have median diameters
of 60 nm and median lengths of 800 nm with the 〈022〉 axis along the length of the nanowire. Electron microscopy, energy dispersive X-ray spectroscopy, powder X-ray diffraction, and electron diffraction are used to characterize the phases and compare nanowires produced with varying
molar ratios of Ti and Zr. Electron diffraction patterns produced from single nanowires show highly crystalline nanowires displaying a compositional-ordering superlattice structure with Zr concentrated in bands within the crystal structure. This is in contrast to naturally occurring bulk srilankite
where Zr and Ti are randomly substituted within the crystal lattice. Streaking is observed in the electron diffraction patterns suggesting short-range ordering within the superlattice structure.
Europium(III) Complexes/Silica Hybrid Nanospheres Synthesized in Microemulsion
Authors: Wang Yan , Qin Weiping , Zhang Jisen , Cao Chunyan , Zhang Jishuang , Jin Ye , Ren Xinguang , Zhu Peifen , Wei Guodong , Wang Guofeng , Wang Lili
Published: March 2008

Eu(DBM)3 Phen/silica nanospheres with a uniform diameter of ∼40 nm and the characteristic fluorescence of Eu3+ ions have been synthesized by a microemulsion method. SEM and TEM analysis indicate that the hybrid nanospheres are core/shell structures with fine
spherical surfaces and that Eu(DBM)3 Phen has been successfully enveloped in the SiO2 spheres as chromophore cores. IR absorption spectra and photoluminescence spectra suggest that the hybrid nanoparticles are promising materials for bioassay.
Surfactant-Assisted Growth of Novel La2(MoO4)3 Dendritic Nanostructures via Facile Hydrothermal Processes
Authors: Zhang Na , Bu Wenbo , Xu Yunpeng , Jiang Danyu , Shi Jianlin
Published: March 2008

In this paper, we report for the first time the successful synthesis of novel uniform La2(MoO4)3 dendritic single-crystalline nanostructures via a surfactant-assisted hydrothermal approach. The dendritic nanostructure is composed of trunks with length
of several micrometers and plenty of side branches. Both of the trunks and the branches are composed of nanoflakes with thickness of 30–50 nm. The branches are oriented nearly parallel to each other and form an angle of about 45° to the trunk. The polyethylene glycol (PEG) acts as
a morphology-directing agent, and by adjusting the experimental parameters, the microstructure of the processed materials could be further controlled in a certain range. The action mechanism of the surfactant has been proposed. This method is a simple and economical route for nanostructure
fabrication and might provide a practical reference to the controlled synthesis of other micro-architectures. In addition, the photoluminescence properties of La2(MoO4)3:Eu dendritic nanostructures were studied.
Mesoscale Processes Contributing to Extreme Rainfall in a Midlatitude Warm-Season Flash Flood
Authors: Schumacher Russ S. , Johnson Richard H.
Published: March 2008

Observations and numerical simulations are used to investigate the atmospheric processes that led to extreme rainfall and resultant destructive flash flooding in eastern Missouri on 6–7 May 2000. In this event, a quasi-stationary mesoscale convective system (MCS) developed near a preexisting mesoscale convective vortex (MCV) in a very moist environment that included a strong low-level jet (LLJ). This nocturnal MCS produced in excess of 300 mm of rain in a small area to the southwest of St. Louis, Missouri. Operational model forecasts and simulations using a convective parameterization scheme failed to produce the observed rainfall totals for this event. However, convection-permitting simulations using the Weather Research and Forecasting Model were successful in reproducing the quasi-stationary organization and evolution of this MCS. In both observations and simulations, scattered elevated convective cells were repeatedly initiated 50–75 km upstream before merging into the mature MCS and contributing to the heavy rainfall. Lifting provided by the interaction between the LLJ and the MCV assisted in initiating and maintaining the convection. Simulations indicate that the MCS was long lived despite the lack of a convectively generated cold pool at the surface. Instead, a nearly stationary low-level gravity wave helped to organize the convection into a quasi-linear system that was conducive to extreme local rainfall amounts. Idealized simulations of convection in a similar environment show that such a low-level gravity wave is a response to diabatic heating and that the vertical wind profile featuring a strong reversal of the wind shear with height is responsible for keeping the wave nearly stationary. In addition, the convective system acted to reintensify the midlevel MCV and also caused a distinct surface low pressure center to develop in both the observed and simulated system.
Race/Ethnicity, Gender and Job Earnings across Metropolitan Areas in the United States: A Multilevel Analysis
Authors: Qingfang Wang
Published: March 2008

Using the US 5 per cent Public Use Microdata Samples (PUMS) and Census Summary Files from the year 2000, and a multilevel linear modelling strategy, this study examines the effects of a range of individual and metropolitan-area characteristics on the job earnings of US-born Whites and Blacks, foreign-born Hispanics and Asians, separately by men and women. The key findings suggest that macroeconomic structure and racial composition have significant influences on interracial and gender earnings disparities, although the direction and magnitude are different among groups. Results also show that all racial and gender groups would benefit from a more evenly distributed labour market among ethnic minorities and immigrants. With respect to gender issues, the earning gaps between racial groups are greater than between men and women. However, compared with men, women workers are more sensitive to macroeconomic conditions, racial residential segregation and labour market segmentation.
Comparative Analysis of the Social, Demographic and Economic Factors that Influenced Housing Choices in Spain in 1990 and 2000
Authors: Colom M. Consuelo , Molés M. Cruz
Published: March 2008

The housing market is an important sector in the economy of any country. Residential demand (also referred to as `housing consumption') depends on many demographic and social characteristics of the country's population and is also related to economic factors. The aim of the present paper was to evaluate the joint effects of economic, demographic and social factors on household behaviour with respect to housing choices. In addition, an attempt was made to determine the impact of recent economic and structural changes in Spanish society (in 1990 and 2000) on residential demand. It was found that the consequences of these structural changes will have medium- and long-term effects on housing demand and that the current economic situation has significantly affected the short-term changes in this demand.
A Study of Exchange and Emotions in Team Member Relationships
Authors: Tse Herman H. M. , Dasborough Marie T.
Published: March 2008

In this article we aim to generate theory about how individuals perceive their relationships with team members, and their emotional experiences within the team member exchange (TMX) process. Findings from qualitative and quantitative analyses are presented, with data collected from 25 full-time employees working within five teams in two organizations. The qualitative results reveal a variety of exchanges that occur within the team member relationships, including relationship-oriented exchanges and task-oriented exchanges. Team members highlighted the importance of friendship within the team context, and that they experienced positive and negative emotions in response to their TMX relationships. The quantitative results also indicated that positive emotions, rather than negative emotions, were associated with high-quality TMX relationships.
Integrative Health and the Management of Pain at the End of Life
Authors: Trevithick Susan G.
Published: March 2008

The blend of complementary alternative medicine (CAM) and traditional Western medicine is known as integrative medicine (IM). It is based on the mind, body, spirit, and community and supports the concept that healing is always possible, even when curing is not; IM is relationship-centered care requiring the active participation of the patient to become more self-aware, to think about their experiences of health and illness, to develop and maintain caring relationships, and to commit to effective communication with the healing team. An integrated treatment strategy to meet the integrative health care needs of the individual is then based on individual CAM therapies. The management of patients at the end of life is often managed through palliative care and acknowledges that dying is a normal part of life. Each healing journey of the mind, the body, and the spirit enriches the individual, the family, and the healing team.
Cultural Dimensions and Framing the Internet in China
Authors: Xiang Zhou
Published: March 2008

/ The current study introduces Hofstede's cultural dimensions into framing research by conducting a cross-cultural comparative analysis of news coverage of the Internet in China from 2000 to 2004 in Hong Kong, Singapore, the US and the UK. Differences were found in terms of both the salience of Internet-related issues and the use of news frames across societies. The patterns of cultural influence of cultural dimensions with interaction effects varied with different types of generic news frames (i.e. human interest, conflict, responsibility, morality and economic consequences). The dimension of long-/short-term orientation was found significant in determining the presence of most types of news frames.
A Matter of Culture
Authors: Yung Soo Kim  , Kelly James D.
Published: March 2008

/ The content of 628 news and feature photographs in 10 elite American and Korean newspapers was analyzed for differences in composition, subject number and subject identification. The Korean approach to photojournalism was purely descriptive while the American approach was more interpretive. Koreans presented far more news, emphasized the group and maintained a consistent composition. Americans ran more features, emphasized the individual and varied composition. Five profession-related factors either reinforce or reflect the observed cultural differences.
Twenty-five–year follow-up among survivors of childhood acute lymphoblastic leukemia: a report from the Childhood Cancer Survivor Study
Authors: Mody Rajen , Li Suwen , Dover Douglas C. , Sallan Stephen , Leisenring Wendy , Oeffinger Kevin C. , Yasui Yutaka , Robison Leslie L. , Neglia Joseph P.
Published: March 2008

Survivors of childhood acute lymphoblastic leukemia (ALL) are at risk for late effects of cancer therapy. Five-year ALL survivors (< 21 years at diagnosis; n = 5760 eligible, 4151 participants), diagnosed from 1970 to 1986 were compared with the general population and a sibling cohort (n = 3899). Cumulative mortality of 5760 5-year survivors was 13% at 25 years from diagnosis. Recurrent ALL (n = 483) and second neoplasms (SNs; n = 89) were the major causes of death. Among 185 survivors, 199 SNs occurred, 53% in the CNS. Survivors reported more multiple chronic medical conditions (CMCs; odds ratio [OR], 2.8; 95% CI, 2.4-3.2) and severe or life-threatening CMCs (OR, 3.6; 95% CI, 3.0-4.5) than siblings. Cumulative incidence of severe CMCs, including death, 25 years from diagnosis was 21.3% (95% CI, 18.2-24.4; 23.3% [95% CI, 19.4-27.2] and 13.4% [95% CI, 8.4-18.4] for irradiated and nonirradiated survivors, respectively). Survivors reported more adverse general and mental health, functional impairment, and activity limitations compared with siblings (P < .001). Rates of marriage, college graduation, employment, and health insurance were all lower compared with sibling controls (P < .001). Long-term survivors of childhood ALL exhibit excess mortality and morbidity. Survivors who received radiation therapy as part of their treatment or had a leukemia relapse are at greatest risk for adverse outcomes.
Exploring evidence-policy linkages in health research plans: A case study from six countries
Authors: Syed Shamsuzzoha B , Hyder Adnan A , Bloom Gerald , Sundaram Sandhya , Bhuiya Abbas , Zhenzhong Zhang , Kanjilal Barun , Oladepo Oladimeji , Pariyo George , Peters David H ,   Future Health Systems: Innovation for Equity
Published: March 2008

The complex evidence-policy interface in low and middle income country settings is receiving increasing attention. Future Health Systems (FHS): Innovations for Equity, is a research consortium conducting health systems explorations in six Asian and African countries: Bangladesh, India, China, Afghanistan, Uganda, and Nigeria. The cross-country research consortium provides a unique opportunity to explore the research-policy interface. Three key activities were undertaken during the initial phase of this five-year project. First, key considerations in strengthening evidence-policy linkages in health system research were developed by FHS researchers through workshops and electronic communications. Four key considerations in strengthening evidence-policy linkages are postulated: development context; research characteristics; decision-making processes; and stakeholder engagement. Second, these four considerations were applied to research proposals in each of the six countries to highlight features in the research plans that potentially strengthen the research-policy interface and opportunities for improvement. Finally, the utility of the approach for setting research priorities in health policy and systems research was reflected upon. These three activities yielded interesting findings. First, developmental consideration with four dimensions – poverty, vulnerabilities, capabilities, and health shocks – provides an entry point in examining research-policy interfaces in the six settings. Second, research plans focused upon on the ground realities in specific countries strengthens the interface. Third, focusing on research prioritized by decision-makers, within a politicized health arena, enhances chances of research influencing action. Lastly, early and continued engagement of multiple stakeholders, from local to national levels, is conducive to enhanced communication at the interface. The approach described has four main utilities: first, systematic analyses of research proposals using key considerations ensure such issues are incorporated into research proposals; second, the exact meaning, significance, and inter-relatedness of these considerations can be explored within the research itself; third, cross-country learning can be enhanced; and finally, translation of evidence into action may be facilitated. Health systems research proposals in low and middle income countries should include reflection on transferring research findings into policy. Such deliberations may be informed by employing the four key considerations suggested in this paper in analyzing research proposals.
Careful adjustment of Epo non-viral gene therapy for β-thalassemic anaemia treatment
Authors: Fabre Emmanuelle E , Bigey Pascal , Beuzard Yves , Scherman Daniel , Payen Emmanuel
Published: March 2008

Background

In situproduction of a secreted therapeutic protein is one of the major gene therapy applications. Nevertheless, the plasmatic secretion peak of transgenic protein may be deleterious in many gene therapy applications including Epo gene therapy. Epo gene transfer appears to be a promising alternative to recombinant Epo therapy for severe anaemia treatment despite polycythemia was reached in many previous studies. Therefore, an accurate level of transgene expression is required for Epo application safety. The aim of this study was to adapt posology and administration schedule of a chosen therapeutic gene to avoid this potentially toxic plasmatic peak and maintain treatment efficiency. The therapeutic potential of repeated muscular electrotransfer of light Epo-plasmid doses was evaluated for anaemia treatment in β-thalassemic mice.

Methods

Muscular electrotransfer of 1 μg, 1.5 μg, 2 μg 4 μg or 6 μg of Epo-plasmid was performed in β-thalassemic mice. Electrotransfer was repeated first after 3.5 or 5 weeks first as a initiating dose and then according to hematocrit evolution.

Results

Muscular electrotransfer of the 1.5 μg Epo-plasmid dose repeated first after 5 weeks and then every 3 months was sufficient to restore a subnormal hematrocrit in β-thalassemic mice for more than 9 months.

Conclusion

This strategy led to efficient, long-lasting and non-toxic treatment of β-thalassemic mouse anaemia avoiding the deleterious initial hematocrit peak and maintaining a normal hematocrit with small fluctuation amplitude. This repeat delivery protocol of light doses of therapeutic gene could be applied to a wide variety of candidate genes as it leads to therapeutic effect reiterations and increases safety by allowing careful therapeutic adjustments.
Adrenergic gene polymorphisms and cardiovascular risk in the NHLBI-sponsored Women's Ischemia Syndrome Evaluation
Authors: Pacanowski Michael A , Zineh Issam , Li Haihong , Johnson B Delia , Cooper-DeHoff Rhonda M , Bittner Vera , McNamara Dennis M , Sharaf Barry L , Merz C Noel Bairey , Pepine Carl J , Johnson Julie A
Published: March 2008

Background

Adrenergic gene polymorphisms are associated with cardiovascular and metabolic phenotypes. We investigated the influence of adrenergic gene polymorphisms on cardiovascular risk in women with suspected myocardial ischemia.

Methods

We genotyped 628 women referred for coronary angiography for eight polymorphisms in the α1A-, β1-, β2- and β3-adrenergic receptors (ADRA1A, ADRB1, ADRB2, ADRB3, respectively), and their signaling proteins, G-protein β 3 subunit (GNB3) and G-protein α subunit (GNAS). We compared the incidence of death, myocardial infarction, stroke, or heart failure between genotype groups in all women and women without obstructive coronary stenoses.

Results

After a median of 5.8 years of follow-up, 115 women had an event. Patients with the ADRB1 Gly389 polymorphism were at higher risk for the composite outcome due to higher rates of myocardial infarction (adjusted hazard ratio [HR] 3.63, 95% confidence interval [95%CI] 1.17–11.28; Gly/Gly vs. Arg/Arg HR 4.14, 95%CI 0.88–19.6). The risk associated with ADRB1 Gly389 was limited to those without obstructive CAD (n = 400, Pinteraction = 0.03), albeit marginally significant in this subset (HR 1.71, 95%CI 0.91–3.19). Additionally, women without obstructive CAD carrying the ADRB3 Arg64 variant were at higher risk for the composite endpoint (HR 2.10, 95%CI 1.05–4.24) due to subtle increases in risk for all of the individual endpoints. No genetic associations were present in women with obstructive CAD.

Conclusion

In this exploratory analysis, common coding polymorphisms in the β1- and β3-adrenergic receptors increased cardiovascular risk in women referred for diagnostic angiography, and could improve risk assessment, particularly for women without evidence of obstructive CAD.

Trial Registration

ClinicalTrials.gov NCT00000554.
Dietary potassium supplementation improves vascular structure and ameliorates the damage caused by cerebral ischemia in normotensive rats
Authors: Rigsby Christine' S , Pollock David M , Dorrance Anne M
Published: March 2008

Background

Dietary potassium supplementation in hypertensive rats is cardioprotective. This protection includes a blood pressure independent reduction in the amount of damage caused by cerebral ischemia. Therefore, we hypothesized that dietary potassium supplementation would improve the outcome of ischemic stroke by improving cerebral vessel structure in normotensive rats.

Methods

Wistar Kyoto (WKY) rats were fed a high (HK) or low potassium (LK) diet for six weeks from six weeks of age. At the end of treatment, cerebral ischemia was induced by middle cerebral artery (MCA) occlusion and the resultant infarct was quantified and expressed as a percentage of the hemisphere infarcted (%HI). MCA structure was assessed in an additional group of rats using a pressurized arteriograph.

Results

The cerebral infarct was significantly smaller in rats fed the HK diet, compared to rats fed the LK diet (21 ± 5.4 vs 33.5 ± 4.8 %HI HK vs LK p < 0.05). Vessel structure was improved in WKY rats fed the HK diet as indicated by an increase in the MCA lumen (298 ± 6.3 vs 276 ± 3.9 μm HK vs LK p < 0.05) and outer diameters (322 ± 7.6 vs 305 ± 4.8 μm HK vs LK p < 0.05). Wall thickness and area were unchanged, suggesting an outward euthrophic remodelling process. The HK diet had no effect on body weight or telemetry blood pressure.

Conclusion

These studies are the first to show a beneficial effect of dietary potassium in rats with normal blood pressure.
The first case report of dental floss pick-related injury presenting with massive hemoptysis: A case report
Authors: Huang Chun-Ta , Ho Chao-Chi , Tsai Yi-Ju , Yang Pan-Chyr
Published: March 2008

Introduction

A tracheobronchial foreign body is a rarely mentioned cause of massive hemoptysis. Although an aspirated toothpick is a well-known cause of traumatic injury to the respiratory tract, a similar device called a dental floss pick, which is much larger than a toothpick, has never been described as a tracheobronchial foreign body.

Case presentation

We report a case of massive hemoptysis in a 32-year-old man due to a dental floss pick in the left main bronchus. Flexible fiberoptic bronchoscopy was successful in removing the foreign body.

Conclusion

Tracheobronchial foreign body can be a medical emergency requiring immediate intervention and massive hemoptysis may be the presenting symptom. Flexible fiberoptic bronchoscopy is recommended as the first-line treatment modality for tracheobronchial foreign body removal. A dental floss pick may present as a tracheobronchial foreign body and can reside in the airway asymptomatically for many years.
Differentiation of angiogenic burden in human cancer xenografts using a perfusion-type optical contrast agent (SIDAG)
Authors: Wall Alexander , Persigehl Thorsten , Hauff Peter , Licha Kai , Schirner Michael , Müller Silke , von Wallbrunn Angelika , Matuszewski Lars , Heindel Walter , Bremer Christoph
Published: March 2008

Introduction

Use of fluorescence imaging in oncology is evolving rapidly, and nontargeted fluorochromes are currently being investigated for clinical application. Here, we investigated whether the degree of tumour angiogenesis can be assessed in vivo by planar and tomographic methods using the perfusion-type cyanine dye SIDAG (1,1'-bis- [4-sulfobutyl]indotricarbocyanine-5,5'-dicarboxylic acid diglucamide monosodium).

Method

Mice were xenografted with moderately (MCF7, DU4475) or highly vascularized (HT1080, MDA-MB435) tumours and scanned up to 24 hours after intravenous SIDAG injection using fluorescence reflectance imaging. Contrast-to-noise ratio was calculated for all tumours, and fluorochrome accumulation was quantified using fluorescence-mediated tomography. The vascular volume fraction of the xenografts, serving as a surrogate marker for angiogenesis, was measured using magnetic resonance imaging, and blood vessel profile (BVP) density and vascular endothelial growth factor expression were determined.

Results

SIDAG accumulation correlated well with angiogenic burden, with maximum contrast to noise ratio for MDA-MB435 (P < 0.0001), followed by HT1080, MCF7 and DU4475 tumours. Fluorescence-mediated tomography revealed 4.6-fold higher fluorochrome concentrations in MDA-MB435 than in DU4475 tumours (229 ± 90 nmol/l versus 49 ± 22 nmol/l; P < 0.05). The vascular volume fraction was 4.5-fold (3.58 ± 0.9% versus 0.8 ± 0.53%; P < 0.01), blood vessel profile density 5-fold (399 ± 36 BVPs/mm2 versus 78 ± 16 BVPs/mm2) and vascular endothelial growth factor expression 4-fold higher for MDA-MB435 than for DU4475 tumours.

Conclusion

Our data suggest that perfusion-type cyanine dyes allow assessment of angiogenesis in vivo using planar or tomographic imaging technology. They may thus facilitate characterization of solid tumours.
Functionally important segments in proteins dissected using Gene Ontology and geometric clustering of peptide fragments
Authors: Manikandan Karuppasamy , Pal Debnath , Ramakumar Suryanarayanarao , Brener Nathan E , Iyengar Sitharama S , Seetharaman Guna
Published: March 2008

We have developed a geometric clustering algorithm using backbone φ,ψ angles to group conformationally similar peptide fragments of any length. By labeling each fragment in the cluster with the level-specific Gene Ontology 'molecular function' term of its protein, we are able to compute statistics for molecular function-propensity and p-value of individual fragments in the cluster. Clustering-cum-statistical analysis for peptide fragments 8 residues in length and with only trans peptide bonds shows that molecular function propensities ≥20 and p-values ≤0.05 can dissect fragments within a protein linked to the molecular function.
Pivotal Advance: Th-1 cytokines inhibit, and Th-2 cytokines promote fibrocyte differentiation
Authors: Shao Diane D , Suresh Rahul , Vakil Varsha , Gomer Richard H , Pilling Darrell
Published: March 2008

CD14+ peripheral blood monocytes can differentiate into fibroblast-like cells called fibrocytes, which are associated with and are at least partially responsible for wound healing and fibrosis in multiple organ systems. Signals regulating fibrocyte differentiation are poorly understood. In this study, we find that when added to human PBMCs cultured in serum-free medium, the profibrotic cytokines IL-4 and IL-13 promote fibrocyte differentiation without inducing fibrocyte or fibrocyte precursor proliferation. We also find that the potent, antifibrotic cytokines IFN-γ and IL-12 inhibit fibrocyte differentiation. In our culture system, IL-1β, IL-3, IL-6, IL-7, IL-16, GM-CSF, M-CSF, fetal liver tyrosine kinase 3, insulin growth factor 1, vascular endothelial growth factor, and TNF-α had no significant effect on fibrocyte differentiation. IL-4, IL-13, and IFN-γ act directly on monocytes to regulate fibrocyte differentiation, and IL-12 acts indirectly, possibly through CD16-positive NK cells. We previously identified the plasma protein serum amyloid P (SAP) as a potent inhibitor of fibrocyte differentiation. When added together, the fibrocyte-inhibitory activity of SAP dominates the profibrocyte activities of IL-4 and IL-13. The profibrocyte activities of IL-4 and IL-13 and the fibrocyte-inhibitory activities of IFN-γ and IL-12 counteract each other in a concentration-dependent manner. These results indicate that the complex mix of cytokines and plasma proteins present in inflammatory lesions, wounds, and fibrosis will influence fibrocyte differentiation.