bluuebunny/crossref_metadata_2025 huggingface dataset:
GEOMETRIC DETECTION OF CHAOS BY USING A DELAYED LORENZ MAP
Authors: OSAKA MOTOHISA
Published: February 2009

To detect determinism and instability geometrically, the Lorenz map zn+1 = f(zn), which projects a local maximum zn to the next local maximum zn+1 of the time series, is useful for such a thin attractor as the Lorenz attractor, but is not applicable for such a "fat" attractor as the Chua circuit. Hence, this study proposes a novel and simple method that is applicable for various attractors. It shows that a T-delayed Lorenz map zn+T = fT(zn), which projects a local maximum zn to the T-delayed local maximum zn+T, is more useful. It was found that the appearance of a parabolic image in a T-delayed Lorenz map is a sign of chaos.
MATHEMATICAL MODELING OF PROSTATE TUMOR GROWTH UNDER INTERMITTENT ANDROGEN SUPPRESSION WITH PARTIAL DIFFERENTIAL EQUATIONS
Authors: GUO QIAN , TAO YOUSHAN , AIHARA KAZUYUKI
Published: February 2009

Since most prostate tumors are initially hormone-sensitive, hormonal therapy with androgen suppression is a major treatment for them. In this hormonal therapy, however, a tumor relapse is a crucial problem. Androgen-independent tumor cells are considered to be responsible for such a relapse. These cells are not sensitive to androgen suppression but rather apt to proliferate even in an androgen-poor environment. Bruchovsky et al. proposed intermittent androgen suppression (IAS), which may prolong the relapse time when compared with continuous androgen suppression (CAS). IAS therapy is based on switching of medication through monitoring of the serum prostate-specific antigen (PSA). Namely, the medication is suspended when the PSA concentration falls below the lower threshold during on-treatment periods and it is reinstituted when the concentration exceeds the upper threshold during off-treatment periods. In this paper, we propose a model of partial differential equations (PDE) for IAS therapy, on the basis of our previous model of ordinary differential equations, under the assumption that the prostate tumor is a mixed assembly of androgen-dependent (AD) and androgen-independent (AI) cells. Numerical analysis compares the effect of the IAS therapy with that of the CAS therapy for different growth rates of the AI cells, which suggests an optimal protocol of the IAS therapy.
TEM INVESTIGATIONS ON CNT-ADDED HEXAGONAL WO3 FILMS FOR SENSING APPLICATIONS
Authors: SEDLÁCKOVÁ KATARÍNA , IONESCU RADU , BALÁZSI CSABA
Published: February 2009

In this work, nanocrystalline hexagonal tungsten oxide was prepared by acidic precipitation from sodium tungstate solution. TEM studies of nanopowders showed that the average size of the hexagonal nanoparticles is 30–50 nm. Novel nanocomposites were prepared by embedding a low amount of gold-decorated carbon nanotubes into the hex- WO 3 matrix. The addition of MWCNTs lowered the temperature range of sensitivity of hex- WO 3 nanocomposites to NO 2 hazardous gas. The sensitivity of hex- WO 3 with Au -decorated MWCNTs to NO 2 is at the temperature range between 25°C and 250°C.
ELECTROCHEMICAL DNA SENSOR TECHNOLOGY FOR MONITORING OF DRUG–DNA INTERACTIONS
Authors: ERDEM A. , KARADENIZ H. , CALISKAN A. , VASEASHTA A.
Published: February 2009

The objective of this investigation is to understand the nature and dynamics of binding small molecules to bio-macromolecules using electrochemical methods. The investigation pertaining to the design of site- and conformation-specific reagents provides a rationale for new studies of drug delivery design. Some anticancer drugs and DNA interactions have been undertaken by using a variety of techniques. Determination of interaction between DNA and DNA-targeted molecules would be valuable in the design of molecule-specific electrochemical biosensors for applications in diagnostics, development of drugs for chemotherapy, and as a biotechnological tool for DNA-based point-of-care diagnosis.
ORGANOPHOSPHATE ADSORPTION ON NANOSIZED SILICA AND SILICA/ALUMINA: SURFACE INTERACTIONS AND BEHAVIOR OF ADSORBENTS
Authors: SIU EULALIA Y. , ANDINO JEAN M.
Published: February 2009

Organophosphate compounds (OPs) are common in pesticides and can be highly toxic. Negative environmental impacts resulting from the release of OPs can be reduced with rapid detection, which relies on sensitive sampling techniques. In this work, nanosized silica and silica/alumina were tested for their ability and behavior in adsorbing gas-phase dimethyl methylphosphonate (DMMP). Surface interactions were probed using Fourier transform infrared (FT-IR) spectroscopy with attenuated total reflectance (ATR) to establish correlations between surface properties and adsorption behavior. Adsorption characteristics were also investigated by gas chromatography (GC) equipped with a flame ionization detector (FID). Silica and silica/alumina adsorbents were exposed to DMMP in a flow system. FT-IR spectroscopy revealed that physical interactions between the adsorbents and DMMP were attributed to the presence of surface silanol. GC-FID results showed that adsorption onto both silica and silica/alumina followed Langmuir isotherm behavior. Silica demonstrated superior adsorption behavior as compared to silica/alumina. The following Langmuir isotherm constants are representative of the data: 0.88 for silica and 0.82 for silica/alumina.
CONTROL OF AIRBORNE NANOPARTICLES RELEASE DURING COMPOUNDING OF POLYMER NANOCOMPOSITES
Authors: TSAI SU-JUNG CANDACE , ASHTER ALI , ADA EARL , MEAD JOEY L. , BARRY CAROL F. , ELLENBECKER MICHAEL J.
Published: February 2009

Polymer nanocomposites, which contain nanoparticles dispersed in a polymer matrix, provide improved properties at low filler loadings. These materials are already produced commercially, with twin-screw extrusion being the preferred process for compounding the nanoparticles and polymer melts. Several recent studies have demonstrated that nanoparticles can enter the body through inhalation, but the risk assessments for nanoparticle exposures are incomplete. Recently, concerns had been expressed that airborne nanoparticles released during compounding might present significant exposure to extruder operators. To assess the impact of the nanoparticles during twin-screw compounding of nanocomposites, researchers with experience in occupational and environmental health and polymer manufacturing monitored the compounding process for a model nanoalumina-containing nanocomposite using a TSI Fast Mobility Particle Spectrometer (FMPS). FMPS measurements were taken at background locations, source locations, and operators' breathing zones. In parallel to the FMPS real time measurement, airborne nanoparticles were collected using polycarbonate filters fitted with filmed grids driven by a personal air sampling pump. Filter samples were analyzed for particle morphology and elemental composition, and the results were found to be in good agreement with particle measurements by FMPS.

Engineering controls and administrative controls were applied to reduce particle release from the compounding process and other operations in the laboratory. The administrative controls dramatically eliminated nanoparticles in the laboratory air, reducing total concentration by as much as 53 000 particles/cm3. Engineering controls were investigated and significant reductions of particle release were attained. The primary solution to reduce exposure level of nanoalumina is to isolate the releasing source. Overall, the engineering controls and administrative controls were effective in reducing airborne nanoparticle release during compounding.
THE POTENTIAL INTRINSIC AND EXTRINSIC TOXICITY OF SILICA NANOPARTICLES AND ITS IMPACT ON MARINE ORGANISMS
Authors: ZHANG HUA , LEUNG YOLANDA , LOUDEN DANIEL , DE NYS ROCKY , LAMB ROBERT
Published: February 2009

The intrinsic and extrinsic toxicity of SiO 2 nanoparticles (Aerosil OX50, ϕ ~ 40 nm) are investigated with a comparison to the particles in micron size ( SiO 2 gel, ϕ ~ 1.5 μ m). Nanoparticles potentially functioned as a carrier of harmful substances transfer was assessed by examining the surface adsorption behavior of the nanoparticles towards γ-picoline (4-methylpyridine), recognized as one type of the marine pollutants, as well as the penetration behavior of the nanoparticles towards a typical marine macro-organism (Caulerpa taxifolia). Silica nanoparticle surface can take up to 2.6 molecules/nm2 of γ-picoline in an aqueous solution comparable to the marine environment. These nanoparticles can further travel onto the surface and into the bulk of the algae (Caulerpa taxifolia) with a depth of ~ 1 μm while carrying toxic γ-picoline. The integrated intrinsic and extrinsic toxicity of SiO 2 nanoparticles has a significant effect on the growth of the algae. The large surface area of the silica nanoparticles results in a high adsorption capability and allows the particles to participate in possible toxic carrier activities in water medium towards marine organisms.
A Standard and Software for Numerical Metadata
Authors: Eijkhout Victor , Fuentes Erika
Published: February 2009

We propose a standard for generating, manipulating, and storing metadata describing numerical problems, in particular properties of matrices and linear systems. The standard comprises:

–an API for metadata generating and querying software, and

–an XML format for permanent storage of metadata.

The API is open-ended, allowing for other parties to define additional metadata categories to be generated and stored within this framework. Furthermore, we present two software libraries, NMD and AnaMod, that implement this standard, and that contain a number of computational modules for numerical metadata. The libraries, more than simply illustrating the use of the standard, provide considerable utility to numerical researchers.
Extra-Precise Iterative Refinement for Overdetermined Least Squares Problems
Authors: Demmel James , Hida Yozo , Riedy E. Jason , Li Xiaoye S.
Published: February 2009

We present the algorithm, error bounds, and numerical results for extra-precise iterative refinement applied to overdetermined linear least squares (LLS) problems. We apply our linear system refinement algorithm to Björck’s augmented linear system formulation of an LLS problem. Our algorithm reduces the forward normwise and componentwise errors to
O
(
ε
w
), where
ε
w
is the working precision, unless the system is too ill conditioned. In contrast to linear systems, we provide two separate error bounds for the solution
x
and the residual
r
. The refinement algorithm requires only limited use of extra precision and adds only
O
(
mn
) work to the
O
(
mn
2
) cost of QR factorization for problems of size
m
-by-
n
. The extra precision calculation is facilitated by the new extended-precision BLAS standard in a portable way, and the refinement algorithm will be included in a future release of LAPACK and can be extended to the other types of least squares problems.
Algorithm 890
Authors: van den Berg Ewout , Friedlander Michael P. , Hennenfent Gilles , Herrmann Felix J. , Saab Rayan , Yilmaz Özgür
Published: February 2009

Sparco is a framework for testing and benchmarking algorithms for sparse reconstruction. It includes a large collection of sparse reconstruction problems drawn from the imaging, compressed sensing, and geophysics literature. Sparco is also a framework for implementing new test problems and can be used as a tool for reproducible research. Sparco is implemented entirely in Matlab, and is released as open-source software under the GNU Public License.
Multivariate partial fraction expansion
Authors: Stoutemyer David R.
Published: February 2009

The Derive computer-algebra program has Expand as one of the menu choices: The user is prompted for successively less main expansion variables, which can be all of the variables or any proper subset. It is clear how to proceed when the expression is a polynomial: Fully distribute with respect to all expansion variables, but collect as coefficient polynomials all terms that share the same exponents for the expansion variables. Derive uses a partially factored form, so the collected coefficient polynomials can be fortuitously partially factored.

For rational expressions the expand function does partial fraction expansion because it is the most useful kind of rational expansion. However, most other computer algebra systems and examples in the literature focus on partial fraction expansion with respect to only one variable, where any other variables are considered mere parameters. For consistency with multivariate polynomial expansion, we wanted a useful and well-defined meaning for multivariate partial fraction expansion. This paper provides such a definition and a corresponding algorithm.
On solving large systems of polynomial equations appearing In discrete differential geometry
Authors: Wolf Thomas
Published: February 2009

The poster describes methods that combined find all solutions of a very large overdetermined polynomial algebraic system for only up to 22 unknowns but with billions of equations all homogeneous of degree 8 with on average millions of terms each. This problem resulted from the classification of all integrable 3-dimensional scalar discrete quasilinear equations Q
3
= 0 on an elementary cubic cell of the lattice Z
3
.
Group actions on gröbner bases of saturated zero-dimensional binomial ideals
Authors: Caboara Massimo , Caruso Fabrizio
Published: February 2009

Fully saturated zero-dimensional binomial ideals (lattice ideals) describe lattices on Z
n
that are of interest in cryptanalysis. Gröbner basis computation for these ideals are computationally very intensive. We sketch a modified version of Buchberger's algorithm for lattice ideals that are closed with respect to a group action on their indeterminates. The main idea is to exploit the symmetries of such ideals to avoid performing S-polynomial reductions that are "equivalent" with respect to the group action. Using our techniques the number of S-polynomials to be considered can be reduced by a factor up to the order of the group.
Computing a rational in between
Authors: Emiris Ioannis , Mourrain Bernard , Tsigaridas Elias
Published: February 2009

We are interested in the following problem: Given two (distinct) real algebraic numbers in isolating interval representation, that is an isolating interval with rational endpoints and a square free polynomial with integer coefficients, can we compute a number between them as a rational function of the coefficients of the polynomials that define these two numbers?

Assume that the order of the two numbers is known (we will remove this assumption in the sequel). If we are given intervals that contain the real algebraic numbers and a procedure to refine them, we can solve our problem as follows: We refine the intervals until they become disjoint, this will happen eventually since we assume that the algebraic numbers are not equal, and then we compute a rational between the intervals, which separates the algebraic numbers. However, this iterative approach depends on separation bounds, e.g. [7]. We present a direct method, which is applicable when we allow in addition to compute the floor of a polynomial expression that involves real algebraic numbers.

The problem arises when we wish to compute rational numbers that isolate the roots of an integer polynomial of small degree, say ≤ 5 [2]. Also in geometry, in order to analyse the intersection of two quadrics
P
and
Q
[6], one needs to determine the real roots of the polynomial det(
P
+
xQ
) = 0, their multiplicities and a value in between each of these roots. Another motivation comes from the arrangement of quadrics [4] In this case a rational is needed separating two real roots of two polynomials with real algebraic numbers as coefficients. The real roots of such polynomials can be expressed as real algerbaic numbers and so we face the problem of computing a rational separating two real algebraic numbers.
The F5 criterion revised
Authors: Arri Alberto
Published: February 2009

The purpose of this work is to generalize the theory behind the "F5" algorithm presented by J.C. Faugère in [3] and its matrix variant described by M. Bardet in [1]. The F5 algorithm is an algorithm which computes the Gröbner basis of a given polynomial ideal
I
from its generators
F
= (
f
1 , ... ,
fm
). Faugère's main idea is to consider the expression of an element
p
∈
I
in terms of the generators,
p
= ∏

h
i
f
i

, and keep explicitly track of the leading term
S
(
p
) of the vector (
h
1
, ... ,
h
m
), taken in its normal form with respect to the module of syzygies of
F
. We provide a novel rigorous proof of a more general criterion than the one stated by Faugère, which establishes when a set of polynomials
G
is a Gröbner basis by considering the values
S
(
g
) for all
g
∈
G
; we further generalize our result by removing the requirement that the sequence
f
1
, ... ,
f
m
is a regular sequence. The criterion itself is based on the knowledge of the module LT(Syz
F
), we have however devised an algorithm which simultaneously computes (a subset of) LT(Syz
F
) and a Gröbner basis of
I
. We had written a first prototypal implementation in C++ using CoCoAlib [2] and we are currently working on a new implementation of the algorithm again in C++ from scratch.
KNOPPIX/Math
Authors: Hamada Tatsuyoshi , KNOPPIX/Math committers
Published: February 2009

KNOPPIX/Math offers many documents and mathematical software packages. Once you run the live system, you can enjoy a wonderful world of mathematical software without needing to install anything yourself. We will demonstrate how to boot and use this system.
Gender Differences in Procedure-Related Adverse Events in Patients Receiving Implantable Cardioverter-Defibrillator Therapy
Authors: Peterson Pamela N. , Daugherty Stacie L. , Wang Yongfei , Vidaillet Humberto J. , Heidenreich Paul A. , Curtis Jeptha P. , Masoudi Frederick A.
Published: February 2009

Background—

Women are at higher risk than men for adverse events with certain invasive cardiac procedures. Our objective was to compare rates of in-hospital adverse events in men and women receiving implantable cardioverter- defibrillator (ICD) therapy in community practice.

Methods and Results—

Using the National Cardiovascular Data Registry ICD Registry, we identified patients undergoing first-time ICD implantation between January 2006 and December 2007. Outcomes included in-hospital adverse events after ICD implantation. Multivariable analysis assessed the association between gender and in-hospital adverse events, with adjustment for demographic, clinical, procedural, physician, and hospital characteristics. Of 161 470 patients, 73% were male, and 27% were female. Women were more likely to have a history of heart failure (81% versus 77%,
P
<0.01), worse New York Heart Association functional status (57% versus 50% in class III and IV,
P
<0.01), and nonischemic cardiomyopathy (44% versus 27%,
P
<0.01) and were more likely to receive biventricular ICDs (39% versus 34%,
P
<0.01). In unadjusted analyses, women were more likely to experience any adverse event (4.4% versus 3.3%,
P
<0.001) and major adverse events (2.0% versus 1.1%,
P
<0.001). In multivariable models, women had a significantly higher risk of any adverse event (OR 1.32, 95% CI 1.24 to 1.39) and major adverse events (OR 1.71, 95% CI 1.57 to 1.86).

Conclusions—

Women are more likely than men to have in-hospital adverse events related to ICD implantation. Efforts are needed to understand the reasons for higher ICD implantation–related adverse event rates in women and to develop strategies to reduce the risk of these events.
Sudden Deaths in Young Competitive Athletes
Authors: Maron Barry J. , Doerer Joseph J. , Haas Tammy S. , Tierney David M. , Mueller Frederick O.
Published: February 2009

Background—

Sudden deaths in young competitive athletes are highly visible events with substantial impact on the physician and lay communities. However, the magnitude of this public health issue has become a source of controversy.

Methods and Results—

To estimate the absolute number of sudden deaths in US competitive athletes, we have assembled a large registry over a 27-year period using systematic identification and tracking strategies. A total of 1866 athletes who died suddenly (or survived cardiac arrest), 19±6 years of age, were identified throughout the United States from 1980 to 2006 in 38 diverse sports. Reports were less common during 1980 to 1993 (576 [31%]) than during 1994 to 2006 (1290 [69%],
P
<0.001) and increased at a rate of 6% per year. Sudden deaths were predominantly due to cardiovascular disease (1049 [56%]), but causes also included blunt trauma that caused structural damage (416 [22%]), commotio cordis (65 [3%]), and heat stroke (46 [2%]). Among the 1049 cardiovascular deaths, the highest number of events in a single year was 76 (2005 and 2006), with an average of 66 deaths per year (range 50 to 76) over the last 6 years; 29% occurred in blacks, 54% in high school students, and 82% with physical exertion during competition/training, whereas only 11% occurred in females (although this increased with time;
P
=0.023). The most common cardiovascular causes were hypertrophic cardiomyopathy (36%) and congenital coronary artery anomalies (17%).

Conclusions—

In this national registry, the absolute number of cardiovascular sudden deaths in young US athletes was somewhat higher than previous estimates but relatively low nevertheless, with a rate of <100 per year. These data are relevant to the current debate surrounding preparticipation screening programs with ECGs and also suggest the need for systematic and mandatory reporting of athlete sudden deaths to a national registry.
Mediterranean Diet and Incidence of and Mortality From Coronary Heart Disease and Stroke in Women
Authors: Fung Teresa T. , Rexrode Kathryn M. , Mantzoros Christos S. , Manson JoAnn E. , Willett Walter C. , Hu Frank B.
Published: February 2009

Background—

Several studies have documented an inverse association between adherence to the Mediterranean diet and risk of coronary heart disease (CHD), but few data are available on the relationship between Mediterranean diet and risk of stroke.

Methods and Results—

For the present study, 74 886 women 38 to 63 years of age in the Nurses’ Health Study, a cohort study of female nurses, without a history of cardiovascular disease and diabetes were followed up from 1984 to 2004. We computed an Alternate Mediterranean Diet Score from self-reported dietary data collected through validated food frequency questionnaires administered 6 times between 1984 and 2002. Relative risks for incident CHD, stroke, and combined fatal cardiovascular disease were estimated with Cox proportional-hazards models adjusted for cardiovascular risk factors. During 20 years of follow-up, 2391 incident cases of CHD, 1763 incident cases of stroke, and 1077 cardiovascular disease deaths (fatal CHD and strokes combined) were ascertained. Women in the top Alternate Mediterranean Diet Score quintile were at lower risk for both CHD and stroke compared with those in the bottom quintile (relative risk [RR], 0.71; 95% CI, 0.62 to 0.82;
P
for trend<0.0001 for CHD; RR, 0.87; 95% CI, 0.73 to 1.02;
P
for trend=0.03 for stroke). Cardiovascular disease mortality was significantly lower among women in the top quintile of the Alternate Mediterranean Diet Score (RR, 0.61; 95% CI, 0.49 to 0.76;
P
for trend<0.0001).

Conclusion—

A greater adherence to the Mediterranean diet, as reflected by a higher Alternate Mediterranean Diet Score, was associated with a lower risk of incident CHD and stroke in women.
Antihypertensive Prescriptions for Newly Treated Patients Before and After the Main Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial Results and Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure Guidelines
Authors: Muntner Paul , Krousel-Wood Marie , Hyre Amanda D. , Stanley Erin , Cushman William C. , Cutler Jeffrey A. , Piller Linda B. , Goforth Gary A. , Whelton Paul K.
Published: February 2009

Main results of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial were published in December 2002. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure, published in May 2003, recommended thiazide-type diuretics as initial pharmacological treatment alone or in combination with another drug in most patients with hypertension. To assess changes from before to after these publications, we compared antihypertensive medication prescriptions filled by patients who initiated pharmacological antihypertensive treatment in a large managed care organization during 3 time periods: (1) July 1, 2001, to June 30, 2002 (before these publications; n=1354); (2) July 1, 2003, to June 30, 2004 (to assess short-term changes; n=1542); and (3) July 1, 2004, to June 30, 2005 (to assess extended changes; n=1865). The percentage of patients initiating antihypertensive treatment with a thiazide-type diuretic increased from 30.6% to 39.4% (
P
<0.001) between 2001–2002 and 2003–2004, and the increase was maintained at 36.5% in 2004–2005 (
P
<0.001 compared with 2001–2002 and
P
=0.33 compared with 2003–2004). Among patients without diabetes mellitus, renal disease, a history of myocardial infarction, or heart failure, the percentage initiating pharmacological antihypertensive treatment with a thiazide-type diuretic increased from 33.1% in 2001–2002 to 43.4% in 2003–2004 (
P
<0.001) and remained increased (41.0%) in 2004–2005 (
P
<0.001 and
P
=0.23 compared with 2001–2002 and 2003–2004, respectively). Despite a sustained increase in the use of thiazide-type diuretics, this study indicates that an opportunity exists to increase adherence to the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure guidelines.
Fasting Plasma Glucose and Serum Lipids in Patients With Primary Aldosteronism
Authors: Matrozova Joanna , Steichen Olivier , Amar Laurence , Zacharieva Sabina , Jeunemaitre Xavier , Plouin Pierre-François
Published: February 2009

An association between primary aldosteronism and metabolism disorders has been reported. The aim of this retrospective study was to test for this association by comparison between large cohorts of patients with primary aldosteronism and with essential hypertension. We retrieved the records of 460 cases with primary aldosteronism (103 lateralized, 150 not lateralized, and 207 undetermined) and of 1363 controls with essential hypertension individually matched for age and sex. We compared clinical history; blood pressure levels; body mass index; levels of fasting plasma glucose and serum triglycerides; total, high-density lipoprotein, and low-density lipoprotein cholesterol; and the prevalence of diabetes mellitus and impaired fasting glucose among subtypes of primary aldosteronism, as well as between cases with primary aldosteronism and their matched controls. Fasting plasma glucose and serum lipid levels did not differ among the 3 subtypes of primary aldosteronism. The prevalence of impaired fasting glucose was lower in patients with primary aldosteronism than their matched controls, but the prevalence of hyperglycemia (impaired fasting glucose or diabetes mellitus) and blood levels of glucose and lipids did not differ between cases and controls. There was no significant difference between preoperative and postoperative levels of either fasting plasma glucose or serum lipids in patients who underwent adrenalectomy and had follow-up data available. The analysis of this large group of patients with primary aldosteronism and essential hypertension does not confirm a higher prevalence of carbohydrate or lipid metabolism disorders in the former. It is unlikely that the prevalence of metabolic syndrome differs significantly between patients with primary aldosteronism and those with essential hypertension.
Onset of Experimental Severe Cardiac Fibrosis Is Mediated by Overexpression of Angiotensin-Converting Enzyme 2
Authors: Masson Rachel , Nicklin Stuart A. , Craig Margaret Anne , McBride Martin , Gilday Kirsten , Gregorevic Paul , Allen James M. , Chamberlain Jeffrey S. , Smith Godfrey , Graham Delyth , Dominiczak Anna F. , Napoli Claudio , Baker Andrew H.
Published: February 2009

Angiotensin-converting enzyme (ACE) 2 is a recently identified homologue of ACE. There is great interest in the therapeutic benefit for ACE2 overexpression in the heart. However, the role of ACE2 in the regulation of cardiac structure and function, as well as maintenance of systemic blood pressure, remains poorly understood. In cell culture, ACE2 overexpression led to markedly increased myocyte volume, assessed in primary rabbit myocytes. To assess ACE2 function in vivo, we used a recombinant adeno-associated virus 6 delivery system to provide 11-week overexpression of ACE2 in the myocardium of stroke-prone spontaneously hypertensive rats. ACE2, as well as the ACE inhibitor enalapril, significantly reduced systolic blood pressure. However, in the heart, ACE2 overexpression resulted in cardiac fibrosis, as assessed by histological analysis with concomitant deficits in ejection fraction and fractional shortening measured by echocardiography. Furthermore, global gene expression profiling demonstrated the activation of profibrotic pathways in the heart mediated by ACE2 gene delivery. This study demonstrates that sustained overexpression of ACE2 in the heart in vivo leads to the onset of severe fibrosis.
Atorvastatin Restores Endothelial Function in Offspring of Protein-Restricted Rats in a Cholesterol-Independent Manner
Authors: Torrens Christopher , Kelsall Christopher J. , Hopkins Laura A. , Anthony Frederick W. , Curzen Nick P. , Hanson Mark A.
Published: February 2009

Maternal protein restriction in rats leads to endothelial dysfunction and decreased NO bioavailability in the offspring. Statins (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) are recognized to have pleiotropic actions including increasing NO bioavailability and reducing inflammation and oxidative damage. This study assessed statin treatment on vascular function in a model of endothelial dysfunction, which is independent of dyslipidemia. Wistar rats were fed a control (18% casein) or protein-restricted (9% casein) diet throughout pregnancy. At weaning, a subset of the protein-restricted group was given atorvastatin (10 mg/kg per day) in the drinking water. At 145 days of age, offspring were euthanized by CO
2
inhalation. Plasma samples were collected for markers of inflammation, vascular reactivity of the thoracic aorta, and small mesenteric arteries were assessed on the wire myograph, and tissues were snap frozen for molecular biology analysis. Thoracic aorta endothelial-dependent vasodilatation was attenuated in the male offspring from both protein-restricted groups compared with controls (
P
<0.05) but was similar in females (
P
value not significant). Endothelial-dependent dilatation of mesenteric arteries was attenuated in male and female protein-restricted offspring (
P
<0.05) and was corrected by atorvastatin. Maternal protein restriction increased plasma inflammatory markers granulocyte chemotactic protein, lipocalin-2, and β
2
-microglobulin in male and C-reactive protein in female offspring (
P
<0.05). Atorvastatin had no effect on inflammatory markers in the males but restored C-reactive protein to control levels in the females (
P
<0.05). Aortic and mesenteric artery mRNA levels of endothelial NO synthase, superoxide dismutase 1, and tumor necrosis factor-α were unchanged. These data suggest that atorvastatin can restore endothelial function in this model, but its effects are gender specific and dependent on the vascular bed.
Attenuation of Cuff-Induced Neointimal Formation by Overexpression of Angiotensin II Type 2 Receptor-Interacting Protein 1
Authors: Fujita Teppei , Mogi Masaki , Min Li-Juan , Iwanami Jun , Tsukuda Kana , Sakata Akiko , Okayama Hideki , Iwai Masaru , Nahmias Clara , Higaki Jitsuo , Horiuchi Masatsugu
Published: February 2009

Recently we have cloned angiotensin II type 2 receptor–interacting protein 1 (ATIP1) as a novel protein that interacts specifically with the C-terminal tail of the angiotensin II type 2 receptor; however, the pathophysiological roles of ATIP1 in vascular remodeling are still unknown. Here, we generated ATIP1-transgenic (ATIP1-Tg) mice expressing mouse ATIP1 and investigated the role of ATIP1 in vascular remodeling using these transgenic mice. ATIP1-Tg mice exhibited no significant difference in blood pressure compared with wild-type (WT) mice. Angiotensin II type 2 receptor mRNA expression in the femoral artery was increased in injured femoral arteries, reaching a peak at 7 days after operation in WT mice, and a similar result of angiotensin II type 2 receptor expression was observed in ATIP1-Tg mice. In ATIP1-Tg mice, neointimal formation of the femoral artery 14 days after cuff placement was significantly smaller than that in WT mice. 5-Bromo-2′-deoxyuridine incorporation was significantly reduced in the injured arteries of ATIP1-Tg mice compared with WT mice. In ATIP1-Tg mice, superoxide anion production and the expression of a proinflammatory cytokine, tumor necrosis factor-α, were markedly attenuated. Moreover, cell proliferative signaling, such as extracellular signal-regulated kinase phosphorylation, was significantly attenuated in ATIP1-Tg mice compared with WT mice. Taken together, these results suggest that ATIP1 plays an important role in cuff-induced vascular remodeling in mice.
Web Survey Design
Authors: Shropshire Kevin O. , Hawdon James E. , Witte James C.
Published: February 2009

Using data from Survey2001, we analyze how visual images embedded in a web-based survey can (1) reduce nonresponse in the specific case that a respondent prematurely terminates the survey and (2) preserve measurement validity. Page-by-page progression through the survey is modeled as a survival process with early termination seen as failure. While images had no apparent effect on the termination process, respondent interest in the survey topic was linked to early termination. These results highlight the importance of placing interest-related questions early in the survey to better control for the effects of interest-driven attrition. Moreover, these findings suggest that an interactional information system approach, one that not only collects data but also pushes relevant information to respondents, may serve to generate or maintain interest and in the process reduce survey attrition.
Estimation for Volunteer Panel Web Surveys Using Propensity Score Adjustment and Calibration Adjustment
Authors: Lee Sunghee , Valliant Richard
Published: February 2009

A combination of propensity score and calibration adjustment is shown to reduce bias in volunteer panel Web surveys. In this combination, the design weights are adjusted by propensity scores to correct for selection bias due to nonrandomized sampling. These adjusted weights are then calibrated to control totals for the target population and correct for coverage bias. The final set of weights is comprised of multiple components, and the estimator of a total no longer takes a linear form. Therefore, approximate methods are needed to derive variance estimates. This study compares three variance estimation methods through simulation. The first method resembles what is used in commercial statistical software based on squared residuals. The second approach uses a variance estimator originally derived for the generalized regression estimator. The third method uses jackknife replication. Results indicate bias reduction is crucial for valid variance estimation and favor the replication method over the other approaches.
Designing Scalar Questions for Web Surveys
Authors: Christian Leah Melani , Parsons Nicholas L. , Dillman Don A.
Published: February 2009

This paper explores how the visual design of scalar questions influences responses in web surveys. We present the results of five experiments embedded in two web surveys of university students. We find that consistently presenting the positive end of the scale first did not impact responses but increases response times. Displaying the categories in multiple columns influence how respondents process the scale and increase response times. Separating the midpoint, ``don't know'' option, or endpoints spatially does not impact responses when the visual and conceptual midpoint align. Removing the graphical layout of the scale influences responses when lower numbers indicate more positive categories and increases response time. Finally, response times are longer for polar point scales with numeric labels, but there are no differences in responses. Overall, our results suggest that the visual design of response scales impacts measurement, but that some manipulations produce larger and more significant differences than others.
Race, Culture, Politics, and Urban Renewal
Authors: Avila Eric , Rose Mark H.
Published: February 2009

When historians refer to “urban renewal,” they are not describing one singular policy. After 1945, as Andrew Highsmith, Irene Holliman, and Guian McKee show, leaders of renewal efforts in Flint, Atlanta, and Philadelphia assumed that a combination of slum clearance, office towers, and expressways would bring white, middle-class people back to downtown. Surprisingly, African American leaders in Flint and Atlanta often cooperated in these plans. In Philadelphia, however, Mayor Frank Rizzo, known as a racist, used renewal funds to create jobs for African American and Puerto Rican women. Federal officials also financed suburbanization, thus channeling resources away from the nation's inner cities and leaving behind a wake of dilapidated infrastructure and racialized poverty. White Americans attributed renewal and suburbanization to the work of markets, overlooking the decisive hand of politicians and public policy. The skewed effects of these renewal and suburbanization programs denote a time “when affirmative action was white.”
From Crackertown to Model City?
Authors: Holliman Irene V.
Published: February 2009

This article uses Atlanta as a case study to examine how proponents of two visions of urban renewal came into conflict in the mid-1960s. Atlanta's mayor, aldermen, and city planners, in conjunction with a few white downtown business associations and some of the city's African American middle class, believed that the purpose of federal renewal funding was to ensure economic growth for the city, either by protecting central business district property values from nearby slums or by constructing new revenue-generating structures. Many of the city's poorer residents rallied alongside housing advocates, civil rights organizations, and neighborhood activists, believing that federal renewal funding should be used to replace deteriorating housing stock, whether with new public housing or low-cost housing built by private developers. This article demonstrates how and where leaders expressing these two visions of urban renewal competed for limited funds, site selection, and planning control.
When Focusing on Negative and Positive Attributes of the Self Elicits More Inductive Self-Judgment
Authors: Klein William M. P. , Monin Matthew M.
Published: February 2009

Self-judgments can range from inductive (i.e., based on relevant characteristics, behaviors, and past experiences) to deductive (i.e., inferred from general beliefs about the self) depending on the situation. Previous work demonstrated that focusing on positive attributes—particularly under threat—can elicit less inductive self-judgment. In this article, the authors tested the hypothesis that priming negative attributes of the self would lead to more inductive self-judgment. The authors also tested whether focusing on positive attributes would lead to more inductive self-judgment in a context where one is constrained to think inductively. In three studies with disparate manipulations, the authors looked at how well participants' self-reported risk factors for health problems were related to their risk perceptions for these health problems. Both hypotheses were supported. The authors discuss implications of these findings for theoretical approaches to self-judgment and practical concerns about the reliability and validity of self-judgments.
The Moderating Role of Autonomy and Control on the Benefits of Written Emotion Expression
Authors: Weinstein Netta , Hodgins Holley S.
Published: February 2009

Two studies examined the hypothesis that relative to control motivation, autonomy motivation is associated with effective written expression and regulation, leading to positive emotional, physical, and cognitive outcomes over time. Participants viewed a Hiroshima—Nagasaki documentary in each of two sessions. Study 1 showed that dispositionally autonomous participants, particularly those who expressed, had positive well-being, energy, and memory after the second viewing. Study 2 explored benefits of situational motivation by priming autonomy and control. Results showed that dispositionally controlled individuals received the same benefits as autonomous individuals only when primed with autonomy and encouraged to express. Coding of writing content revealed that the benefits of autonomy were mediated by nondefensive and effective emotional processing, as reflected in greater use of self-referencing and cognitive mechanism words and lower use of concrete words. Results support the expectation that autonomy relates to effective expression and emotion regulation, leading to positive functioning over time.
Sample size determination for the non-randomised triangular model for sensitive questions in a survey
Authors: Tian Guo-Liang , Tang Man-Lai , Zhenqiu Liu  , Ming Tan  , Tang Nian-Sheng
Published: February 2009

Sample size determination is an essential component in public health survey designs on sensitive topics (e.g. drug abuse, homosexuality, induced abortions and pre or extramarital sex). Recently, non-randomised models have been shown to be an efficient and cost effective design when comparing with randomised response models. However, sample size formulae for such non-randomised designs are not yet available. In this article, we derive sample size formulae for the non-randomised triangular design based on the power analysis approach. We first consider the one-sample problem. Power functions and their corresponding sample size formulae for the one- and two-sided tests based on the large-sample normal approximation are derived. The performance of the sample size formulae is evaluated in terms of (i) the accuracy of the power values based on the estimated sample sizes and (ii) the sample size ratio of the non-randomised triangular design and the design of direct questioning (DDQ). We also numerically compare the sample sizes required for the randomised Warner design with those required for the DDQ and the non-randomised triangular design. Theoretical justification is provided. Furthermore, we extend the one-sample problem to the two-sample problem. An example based on an induced abortion study in Taiwan is presented to illustrate the proposed methods.
Stochastic models of sequence evolution including insertion—deletion events
Authors: Miklós István , Novák Ádám , Satija Rahul , Lyngsø Rune , Hein Jotun
Published: February 2009

Comparison of sequences that have descended from a common ancestor based on an explicit stochastic model of substitutions, insertions and deletions has risen to prominence in the last decade. Making statements about the positions of insertions-deletions (abbr. indels) is central in sequence and genome analysis and is called alignment. This statistical approach is harder conceptually and computationally, than competing approaches based on choosing an alignment according to some optimality criteria. But it has major practical advantages in terms of testing evolutionary hypotheses and parameter estimation. Basic dynamic approaches can allow the analysis of up to 4—5 sequences. MCMC techniques can bring this to about 10—15 sequences. Beyond this, different or heuristic approaches must be used. Besides the computational challenges, increasing realism in the underlying models is presently being addressed. A recent development that has been especially fruitful is combining statistical alignment with the problem of sequence annotation, making statements about the function of each nucleotide/amino acid. So far gene finding, protein secondary structure prediction and regulatory signal detection has been tackled within this framework. Much progress can be reported, but clearly major challenges remain if this approach is to be central in the analyses of large incoming sequence data sets.
The Korean press and Hwang’s fraud
Authors: Park Jaeyung , Jeon Hyoungjoon , Logan Robert A.
Published: February 2009

This case study explores why South Korean journalists overlooked allegations of scientific misconduct against South Korean scientist Dr. Woo Suk Hwang and even indirectly defended him in 2005—6. Nineteen journalists, who covered Hwang’s story for five of South Korea’s leading daily newspapers, were interviewed. The interviewees added insights about the news coverage of the Hwang scandal not identified in previous literature, such as the difficulties among journalists to suspend their personal disbelief about the criticisms and evidence against Hwang. The findings suggest the news judgments that occurred in Korean newsrooms during the Hwang scandal reflected a socially constructed process of negotiation among news media professionals and between journalists and scientists. The findings also suggest it may be best to consider journalistic mores within a multidimensional framework that includes journalistic perceptions of socio-cultural norms, internal newsroom standards for evidence, newsroom competence and training, normative journalism ethics, news gathering techniques, perceived dissonance and professed risk avoidance.
Research and reporting on the development of sex in fetuses: gendered from the start
Authors: Dingel Molly J. , Sprague Joey
Published: February 2009

Research into human genetics has been expanding rapidly and most people learn about that research from mass media. Because prior research finds gender bias in aspects of both science and the media, we investigate the messages presented to the public concerning the relationship between biology and gender, taking as a case research on the genetic development of sexual difference before birth. We examine both the science that is getting media attention and the form that coverage takes. We find that gendered assumptions direct the science but also that scholarly discourse makes gender biases in method and interpretation accessible to scientific critique. On the other hand, mass media reporting ignores feminist critiques, marginalizes women and dramatically reinscribes gendered beliefs about the inherent superiority of men and the biological basis for gender differences in personality and behavior.
Public understanding of science and technology embedded in complex institutional settings
Authors: Lach Denise , Sanford Stephanie
Published: February 2009

We use a constructivist analysis to describe how citizens learn and integrate highly technical scientific information about a new technology (bioremediation) within the context of a risk-based relationship with a federal agency in their own backyards. We engaged members of the general public in a workshop process where they produced a consensus report that describes how bioremediation works, characterizes the scientific issues not yet addressed, and sets the problem within the context of institutional arrangements for the production of knowledge. On the basis of their social roles in their communities, they applied new knowledge to their own experiences and worked at ways to translate their understanding of the technology into information that could be used in their multiple roles as learners in the workshop, as well as citizens and family members outside the workshop.