bluuebunny/crossref_metadata_2025 huggingface dataset:
Resting States Affect Spontaneous BOLD Oscillations in Sensory and Paralimbic Cortex
Authors: McAvoy Mark , Larson-Prior Linda , Nolan Tracy S. , Vaishnavi S. Neil , Raichle Marcus E. , d'Avossa Giovanni
Published: May 2008

The brain exhibits spontaneous neural activity that depends on the behavioral state of the organism. We asked whether the blood oxygenation level-dependent (BOLD) signal reflects these modulations. BOLD was measured under three steady-state conditions: while subjects kept their eyes closed, kept their eyes open, or while fixating. The BOLD spectral density was calculated across brain voxels and subjects. Visual, sensory-motor, auditory, and retrosplenial cortex showed modulations of the BOLD spectral density by resting state type. All modulated regions showed greater spontaneous BOLD oscillations in the eyes closed than the eyes open or fixation conditions, suggesting that the differences were endogenously driven. Next, we examined the pattern of correlations between regions whose ongoing BOLD signal was modulated by resting state type. Regional neuronal correlations were estimated using an analytic procedure from the comparison of BOLD–BOLD covariances in the fixation and eyes closed conditions. Most regions were highly correlated with one another, with the exception of the primary visual cortices, which showed low correlations with the other regions. In conclusion, changes in resting state were associated with synchronous modulations of spontaneous BOLD oscillations in cortical sensory areas driven by two spatially overlapping, but temporally uncorrelated signals.
Activation and Molecular Targets of Peroxisome Proliferator‐Activated Receptor‐γ Ligands in Lung Cancer
Authors: Nemenoff Raphael A. , Weiser-Evans Mary , Winn Robert A.
Published: May 2008

Lung cancer is the leading cause of cancer death, and five‐year survival remains poor, raising the urgency for new treatment strategies. Activation of PPARγ represents a potential target for both the treatment and prevention of lung cancer. Numerous studies have examined the effect of thiazolidinediones such as rosiglitazone and pioglitazone on lung cancer cells in vitro and in xenograft models. These studies indicate that activation of PPARγ inhibits cancer cell proliferation as well as invasiveness and metastasis. While activation of PPARγ can occur by direct binding of pharmacological ligands to the molecule, emerging data indicate that PPARγ activation can occur through engagement of other signal transduction pathways, including Wnt signaling and prostaglandin production. Data, both from preclinical models and retrospective clinical studies, indicate that activation of PPARγ may represent an attractive chemopreventive strategy. This article reviews the existing biological and mechanistic experiments focusing on the role of PPARγ in lung cancer, focusing specifically on nonsmall cell lung cancer.
On Different Classes of Algebraic Polynomials with Random Coefficients
Authors: Farahmand K. , Grigorash A. , McGuinness B.
Published: May 2008

The expected number of real zeros of the polynomial of the form a0 + a1x + a2x2 + ⋯+anxn, where a0, a1, a2, …, an is a sequence of standard
Gaussian random variables, is known. For n large it is shown that this expected
number in (−∞, ∞) is asymptotic to (2/π)log n. In this paper, we show that
this asymptotic value increases significantly to when we consider a
polynomial in the form instead. We give the motivation for our choice of
polynomial and also obtain some other characteristics for the polynomial, such
as the expected number of level crossings or maxima. We note, and present,
a small modification to the definition of our polynomial which improves our
result from the above asymptotic relation to the equality.
The Role of PPARγ in Hepatocellular Carcinoma
Authors: Borbath Ivan , Horsmans Yves
Published: May 2008

Hepatocellular carcinoma (HCC) is the third leading cause of cancer‐related death worldwide. This cancer develops mainly in cirrhotic patients. The cirrhotic liver is considered to be a preneoplastic organ, suggesting the rationale for cancer prevention. PPARγ is a nuclear transcription factor whose activation leads to interaction in the metabolism of lipids, insulin sensitization of peripheral cells, anti‐inflammatory action. It can also induce differentiation and inhibits proliferation of cancer cells. Until now, data using PPARγ ligands in HCC have demonstrated mainly in in vitro models that its activation could be due to an antiproliferative effect. PPARγ ligand administration has also been associated with a diminution of liver fibrosis in animal models, and potentially also on tumoral cell death. Soma data show that the favorable effect of natural and synthetized PPARγ agonists could also be independent of PPARγ activation. Furthermore, in some situations, PPARγ antagonists have also an anticancer effect. Therefore, we can conclude that the link between activation of the PPARγ pathway and an anticancer activity is suggested but until now not firmly established in HCC.
Selected Area XPS Analysis for Identification of Pigment Compounds in Microscopic Paint Flakes
Authors: Joanne James Bryony , Cameron Rebecca , Baskcomb Camilla
Published: May 2008

The application of X-ray photoelectron spectroscopy to the analysis of paint flakes from a painting by Henry Fuseli (1741–1825) is presented. Historically, the application of XPS to art conservation and restoration studies has been limited by the poor spatial resolution of the technique. Presented here is the successful analysis of paint flakes in the order of 100 μm using “imaging” XPS in conjunction with selected area analysis. Raman microscopy failed to satisfactorily identify the compounds present in this instance, and energy dispersive spectroscopy could not differentiate between lead and sulphur (two of the elements of interest) due to the limited energy resolution inherent in that technique. Using XPS analysis of the lead 4f peak revealed that the pigment was a lead-based pigment, in this case comprising exclusively lead-sulphur compounds.
PPAR‐γ Thiazolidinedione Agonists and Immunotherapy in the Treatment of Brain Tumors
Authors: Lichtor Terry , Spagnolo Alessandra , Glick Roberta P. , Feinstein Douglas L.
Published: May 2008

Thiazolidinediones (TZDs) are selective agonists of the peroxisome proliferator‐activated receptor (PPAR) gamma, a transcription factor belonging to the superfamily of nuclear hormone receptors. Although activation of PPARγ by TZDs has been best characterized by its ability to regulate expression of genes associated with lipid metabolism, PPARγ agonists have other physiological effects including modulating pro‐ and anti‐inflammatory gene expression and inducing apoptosis in several cell types including glioma cells and cell lines. Immunotherapeutic approaches to reducing brain tumors are focused on means to reduce the immunosuppressive responses of tumors which dampen the ability of cytotoxic T‐lymphocytes to kill tumors. Initial studies from our lab show that combination of an immunotherapeutic strategy with TZD treatment provides synergistic benefit in animals with implanted tumors. The potential of this combined approach for treatment of brain tumors is reviewed in this report.
History and Diagnostic Significance of C‐Peptide
Authors: Brandenburg Dietrich
Published: May 2008

Starting with the epoch‐making discovery of proinsulin, C‐peptide has played an important interdisciplinary role, both as part of the single‐chain precursor molecule and as an individual entity. In the pioneering years, fundamental systematic experiments unravelled new biochemical mechanisms and chemical structures. After the first detection of C‐peptide in human serum, it quickly became a most useful independent indicator of insulin biosynthesis and secretion, finding application in a rapidly growing number of clinical investigations. A prerequisite was the development of specific immuno assays for proinsulin and C‐peptide.
Further milestones were: the chemical synthesis of several C‐peptides and the accomplishments in the synthesis of proinsulin; the detection of preproinsulin with its bearings on understanding protein biosynthesis; the pioneering role of insulin, proinsulin, C‐peptide, and mini‐C‐peptides in the development of recombinant DNA technology; and the discovery of the enzymes for the endoproteolytic processing of proinsulin into insulin and C‐peptide, completing the pathway of biosynthesis.
Today, C‐peptide continues to serve as a special diagnostic tool in Diabetology and related fields. Thus, its passive role is well established. Evidence for its active role in physiology and pathophysiology is more recent and is subject of the following contributions.
Exact Solutions of Rayleigh‐Stokes Problem for Heated Generalized Maxwell Fluid in a Porous Half‐Space
Authors: Xue Changfeng , Nie Junxiang
Published: May 2008

The Rayleigh‐Stokes problem for a generalized Maxwell fluid in a porous
half‐space with a heated flat plate is investigated. For the description of such a
viscoelastic fluid, a fractional calculus approach in the constitutive relationship
model is used. By using the Fourier sine transform and the fractional Laplace
transform, exact solutions of the velocity and the temperature are obtained.
Some classical results can be regarded as particular cases of our results, such
as the classical solutions of the first problem of Stokes for Newtonian viscous
fluids, Maxwell fluids, and Maxwell fluids in a porous half‐space.
Single-Trial Decoding of Bistable Perception Based on Sparse Nonnegative Tensor Decomposition
Authors: Wang Zhisong , Maier Alexander , Logothetis Nikos K. , Liang Hualou
Published: May 2008

The study of the neuronal correlates of the spontaneous alternation in perception elicited by bistable visual stimuli is promising for understanding the mechanism of neural information processing and the neural basis of visual perception and perceptual decision-making. In this paper, we develop a sparse nonnegative tensor factorization-(NTF)-based method to extract features from the local field potential (LFP), collected from the middle temporal (MT) visual cortex in a macaque monkey, for decoding its bistable structure-from-motion (SFM) perception. We apply the feature extraction approach to the multichannel time-frequency representation of the intracortical LFP data. The advantages of the sparse NTF-based feature extraction approach lies in its capability to yield components common across the space, time, and frequency domains yet discriminative across different conditions without prior knowledge of the discriminating frequency bands and temporal windows for a specific subject. We employ the support vector machines (SVMs) classifier based on the features of the NTF components for single-trial decoding the reported perception. Our results suggest that although other bands also have certain discriminability, the gamma band feature carries the most discriminative information for bistable perception, and that imposing the sparseness constraints on the nonnegative tensor factorization improves extraction of this feature.
Diffusion Enhanced Upconversion in Organic Systems
Authors: Monguzzi A. , Tubino R. , Meinardi F.
Published: May 2008

The upconverted fluorescence generation in a solution of multicomponent organic systems has been
studied as a function of the temperature to investigate the role of resonant energy transfer processes and of the molecular diffusion on the overall emission yield. The strong blue emission observed exciting the samples at 532 nm derives from a bimolecular triplet‐triplet annihilation between 9,10 diphenylanthracene molecules, which produces singlet excited states from which the higher energy emission takes place. Diphenylanthracene excited triplet states are populated by energy transfer from a phosphorescent donor (Pt(II)octaethylporphyrin) which acts as excitation light harvesting.
At low temperature, the experimental data on the efficiency of the transfer have been interpreted in the frame of a Dexter energy transfer in the Perrin approximation. At room temperature, the fast
diffusion of the molecules has been found to be the main factor which affects the energy transfer rates and the overall photon upconversion efficiency.
Fuzzy Coordinated PI Controller: Application to the Real‐Time Pressure Control Process
Authors: Kanagaraj N. , Sivashanmugam P. , Paramasivam S.
Published: May 2008

This paper presents the real‐time implementation of a fuzzy coordinated classical PI control scheme for controlling the pressure in a pilot pressure tank system. The fuzzy system has been designed to track the variation parameters in a feedback loop and tune the classical controller to achieve a better control action for load disturbances and set point changes. The error and process inputs are chosen as the inputs of fuzzy system to tune the conventional PI controller according to the process condition. This online conventional controller tuning technique will reduce the human involvement in controller tuning and increase the operating range of the conventional controller. The proposed control algorithm is experimentally implemented for the real‐time pressure control of a pilot air tank system and validated using a high‐speed 32‐bit ARM7 embedded microcontroller board (ATMEL AT91M55800A). To demonstrate the performance of the fuzzy coordinated PI control scheme, results are compared with a classical PI and PI‐type fuzzy control method. It is observed that the proposed controller structure is able to quickly track the parameter variation and perform better in load disturbances and also for set point changes.
TEM Nanostructural Study of Al-6Si-3Cu-Mg Melt-Spun Ribbons
Authors: López Ismeli Alfonso , Zepeda Cuauhtémoc Maldonado , Reyes Gonzalo González , Flores Ariosto Medina , Rodríguez Juan Serrato
Published: May 2008

Three quaternary Al-6Si-3Cu-xMg (x= 0.59, 3.80, and 6.78 wt.%) alloys were produced by melt-spun and characterized using X-ray diffractometry (XRD), transmission electron microscopy (TEM), and microhardness techniques. Obtained second phases were for the alloy with 0.59% Mg and (Q) for the alloys with 3.80 and 6.78% Mg. These phases are present as 30–50 nm or as 5–10 nm nanoparticles. Alloying elements content in solid solution increased, mainly for Si and Mg. The high alloying elements content in solid solution and the small -Al cell size for melt-spun alloys leads to microhardness values about 2 times higher than those of ingot counterparts. The microhardness increase for melt-spun alloys with 3.80 and 6.78% Mg depends on Mg content in solid solution.
Breast Tumor Simulation and Parameters Estimation Using Evolutionary Algorithms
Authors: Mital Manu , Pidaparti Ramana M.
Published: May 2008

An estimation methodology is presented to determine the breast tumor parameters using the surface temperature profile that may be obtained by infrared thermography. The estimation methodology involves evolutionary algorithms using artificial neural network (ANN) and genetic algorithm (GA). The ANN is used to map the relationship of tumor parameters (depth, size, and heat generation) to the temperature profile over the idealized breast model. The relationship obtained from ANN is compared to that obtained by finite element software. Results from ANN training/testing were in good agreement with those obtained from finite element model. After ANN validation, GA is used to estimate tumor parameters by minimizing a fitness function involving comparing the temperature profiles from simulated or clinical data to those obtained by ANN. Results show that it is possible to determine the depth, diameter, and heat generation rate from the surface temperature data (with 5% random noise) with good accuracy for the 2D model. With 10% noise, the accuracy of estimation deteriorates for deep‐seated tumors with low heat generation. In order to further develop this methodology for use in a clinical scenario, several aspects such as 3D breast geometry and the effects of nonuniform cooling should be considered in future investigations.
A Photocatalytic Active Adsorbent for Gas Cleaning in a Fixed Bed Reactor
Authors: Pucher Peter , Azouani Rabah , Kanaev Andrei , Krammer Gernot
Published: May 2008

Efficient photocatalysis for gas cleaning purposes requires a large accessible, illuminated active surface in a simple and compact reactor. Conventional concepts use powdered catalysts, which are nontransparent. Hence a uniform distribution of light is difficult to be attained. Our approach is based on a coarse granular, UV‐A light transparent, and highly porous adsorbent that can be used in a simple fixed bed reactor. A novel sol‐gel process with rapid micro mixing is used to coat a porous silica substrate with TiO2‐based nanoparticles. The resulting material posses a high adsorption capacity and a photocatalytic activity under UV‐A illumination (PCAA = photocatalytic active adsorbent). Its photocatalytic performance was studied on the oxidation of trichloroethylene (TCE) in a fixed bed reactor setup in continuous and discontinuous operation modes. Continuous operation resulted in a higher conversion rate due to less slip while discontinuous operation is superior for a total oxidation to CO2 due to a user‐defined longer residence time.
Multiple Gate Delay Tracking Structures for GNSS Signals and Their Evaluation with Simulink, SystemC, and VHDL
Authors: Hurskainen Heikki , Simona Lohan Elena , Hu Xuan , Raasakka Jussi , Nurmi Jari
Published: May 2008

Accurate delay tracking in multipath environments is one of the prerequisites of modern GNSS receivers.
Several solutions have been proposed in the literature, both feedback and feedforward. However, this
topic is still under active research focus, especially for mass‐market receivers, where selection of lowcomplexity,
nonpatented methods is preferred. Among the most encountered delay tracking structures
implemented in today′s receivers, we have the narrow correlator and the double‐delta correlators. Both
are heavily covered by various patents. The purpose of this paper is to introduce a new, generic structure,
called multiple gate delay (MGD) structure, which covers also the patented correlators but offers much
more flexibility in the design process. We show how the design parameters of such a structure can be
optimized, we argue the performance of this structure via detailed simulation results based on various
simulators, such as Matlab/Simulink‐based tool, GRANADA, and we test the implementation feasibility of
MGD structures on actual devices, via SystemC and FPGA prototyping. One of the main advantages of
the proposed structure is its high degree of flexibility, which allows the designer to choose among, to the
authors′ knowledge, nonpatented solutions with delay tracking accuracy comparable with that of the
current state‐of‐art trackers.
Access Network Selection Based on Fuzzy Logic and Genetic Algorithms
Authors: Alkhawlani Mohammed , Ayesh Aladdin
Published: May 2008

In the next generation of heterogeneous wireless networks (HWNs), a large number of different radio access technologies (RATs) will be integrated into a common network. In this type of networks, selecting the most optimal and promising access network (AN) is an important consideration for overall networks stability, resource utilization, user satisfaction, and quality of service (QoS) provisioning. This paper proposes a general scheme to solve the access network selection (ANS) problem in the HWN. The proposed scheme has been used to present and design a general multicriteria software assistant (SA) that can consider the user, operator, and/or the QoS view points. Combined fuzzy logic (FL) and genetic algorithms (GAs) have been used to give the proposed scheme the required scalability, flexibility, and simplicity. The simulation results show that the proposed scheme and SA have better and more robust performance over the random-based selection.
Role of Peroxisome Proliferator‐Activated Receptor Gamma and Its Ligands in the Treatment of Hematological Malignancies
Authors: Garcia-Bates Tatiana M. , Lehmann Geniece M. , Simpson-Haidaris Patricia J. , Bernstein Steven H. , Sime Patricia J. , Phipps Richard P.
Published: May 2008

Peroxisome proliferator‐activated receptor gamma (PPARγ) is a multifunctional transcription factor with important regulatory roles in inflammation, cellular growth, differentiation, and apoptosis. PPARγ is expressed in a variety of immune cells as well as in numerous leukemias and lymphomas. Here, we review recent studies that provide new insights into the mechanisms by which PPARγ ligands influence hematological malignant cell growth, differentiation, and survival. Understanding the diverse properties of PPARγ ligands is crucial for the development of new therapeutic approaches for hematological malignancies.
Cobalamin Deficiency in Elderly Patients: A Personal View
Authors: Andrès Emmanuel , Vogel Thomas , Federici Laure , Zimmer Jacques , Ciobanu Ecaterina , Kaltenbach Georges
Published: May 2008

Cobalamin (vitamin B12) deficiency is particularly common in the elderly (>65 years of age) but is often unrecognized because its clinical manifestations are subtle; however, they are also potentially serious, particularly from a neuropsychiatric and hematological perspective. In the elderly, the main causes of cobalamin deficiency are pernicious anemia and food-cobalamin malabsorption. Food-cobalamin malabsorption syndrome is a disorder characterized by the inability to release cobalamin from food or its binding proteins. This syndrome is usually caused by atrophic gastritis, related or unrelated toHelicobacter pyloriinfection, and long-term ingestion of antacids and biguanides. Management of cobalamin deficiency with cobalamin injections is currently well documented but new routes of cobalamin administration (oral and nasal) are being studied, especially oral cobalamin therapy for food-cobalamin malabsorption.
Asymptotic Behavior of Solutions for Nonlinear Volterra Discrete Equations
Authors: Messina E. , Muroya Y. , Russo E. , Vecchio A.
Published: May 2008

We consider nonlinear difference equations of unbounded order of the form ,  i = 0, 1, 2, …, where fj(x)  (j = 0, …, i) are suitable functions. We establish sufficient conditions for the boundedness and the convergence of xi as i → +∞. Some of these conditions are interesting mainly for studying stability of numerical methods for Volterra integral equations.
An Adaptive Resolution Computationally Efficient Short‐Time Fourier Transform
Authors: Qaisar Saeed Mian , Fesquet Laurent , Renaudin Marc
Published: May 2008

The short‐time Fourier transform (STFT) is a classical tool, used for characterizing the time varying signals. The limitation of the STFT is its fixed time‐frequency resolution. Thus, an enhanced version of the STFT, which is based on the cross‐level sampling, is devised. It can adapt the sampling frequency and the window function length by following the input signal local characteristics. Therefore, it provides an adaptive resolution time‐frequency representation of the input signal. The computational complexity of the proposed STFT is deduced and compared to the classical one. The results show a significant gain of the computational efficiency and hence of the processing power.
Death in Heart Failure
Authors: Henkel Danielle M. , Redfield Margaret M. , Weston Susan A. , Gerber Yariv , Roger Véronique L.
Published: May 2008

Background—

Mortality in patients with heart failure (HF) remains high, but causes of death are incompletely defined. As HF is a heterogeneous syndrome categorized according to the ejection fraction (EF), the association between EF and causes of death is important, yet elusive.

Methods and Results—

Community subjects with HF were classified according to the preserved (≥50%) and the reduced EF (<50%). Deaths were classified as due to coronary heart disease and other cardiovascular and noncardiovascular diseases. Among 1063 persons with HF, 45% had preserved EF with fewer cardiovascular risk factors and less coronary disease than those with reduced EF. At 5 years, survival was 45% (95% CI, 43% to 49%), and 43% of the deaths were noncardiovascular. The leading cause of death in subjects with preserved EF was noncardiovascular disease (49%) versus coronary heart disease (43%) for subjects with reduced EF. The proportion of cardiovascular deaths decreased from 69% in 1979–1984 to 40% in 1997–2002 (
P
=0.007) among subjects with preserved EF, which is in contrast to a modest change among those with reduced EF (77% to 64%,
P
=0.08). Advanced age, male sex, diabetes, smoking, and kidney disease were associated with an increased risk of all-cause and cardiovascular deaths. After adjustment, preserved EF was associated with a lower risk of cardiovascular death but not all-cause death.

Conclusions—

Community subjects with HF experience a persistently high mortality, and a large proportion of deaths is noncardiovascular. Cardiovascular disease before death is less in subjects with preserved EF, and they are less likely to experience cardiovascular deaths compared with those with reduced EF. In those with preserved EF, the proportion of cardiovascular deaths declined over time.
Long-Term Prospective, Randomized, Controlled Study Using Repetitive Education at Six-Month Intervals and Monitoring for Adherence in Heart Failure Outpatients
Authors: Bocchi Edimar Alcides , Cruz Fátima , Guimarães Guilherme , Pinho Moreira Luiz Felipe , Issa Victor Sarli , Ayub Ferreira Silvia Moreira , Chizzola Paulo Roberto , Souza Germano Emilio Conceição , Brandão Sara , Bacal Fernando
Published: May 2008

Background—

The effectiveness of heart failure disease management programs in patients under cardiologists’ care over long-term follow-up is not established.

Methods and Results—

We investigated the effects of a disease management program with repetitive education and telephone monitoring on primary (combined death or unplanned first hospitalization and quality-of-life changes) and secondary end points (hospitalization, death, and adherence). The REMADHE [Repetitive Education and Monitoring for ADherence for Heart Failure] trial is a long-term randomized, prospective, parallel trial designed to compare intervention with control. One hundred seventeen patients were randomized to usual care, and 233 to additional intervention. The mean follow-up was 2.47�1.75 years, with 54% adherence to the program. In the intervention group, the primary end point composite of death or unplanned hospitalization was reduced (hazard ratio, 0.64; confidence interval, 0.43 to 0.88;
P
=0.008), driven by reduction in hospitalization. The quality-of-life questionnaire score improved only in the intervention group (
P
<0.003). Mortality was similar in both groups. Number of hospitalizations (1.3�1.7 versus 0.8�1.3,
P
<0.0001), total hospital days during the follow-up (19.9�51 versus 11.1�24 days,
P
<0.0001), and the need for emergency visits (4.5�10.6 versus 1.6�2.4,
P
<0.0001) were lower in the intervention group. Beneficial effects were homogeneous for sex, race, diabetes and no diabetes, age, functional class, and etiology.

Conclusions—

For a longer follow-up period than in previous studies, this heart failure disease management program model of patients under the supervision of a cardiologist is associated with a reduction in unplanned hospitalization, a reduction of total hospital days, and a reduced need for emergency care, as well as improved quality of life, despite modest program adherence over time.
Hemodynamic, Hormonal, and Renal Actions of Adrenomedullin 2 in Experimental Heart Failure
Authors: Rademaker Miriam T. , Charles Christopher J. , Nicholls M. Gary , Richards A. Mark
Published: May 2008

Background—

Adrenomedullin 2 (AM2) is a novel member of the calcitonin gene-related peptide family that is thought to play a regulatory role in circulatory homeostasis under normal physiological conditions. The effects of AM2 in heart failure have not been investigated previously.

Methods and Results—

Two incremental doses of human AM2 (10 and 100 ng[kg�min] for 90 minutes each) were given by intravenous infusion to 8 sheep with pacing-induced heart failure. Compared with time-matched control infusions, AM2 produced dose-dependent increases in left ventricular dP/dt(max) (control 1168�138 mm Hg/s versus AM2 high-dose 1402�130 mm Hg/s;
P
<0.01) and cardiac output (2.09�0.66 L/min versus 3.81�0.30 L/min;
P
<0.001) and reductions in calculated total peripheral resistance (40�6 mm Hg(L�min) versus 21�4 mm Hg(L�min);
P
<0.001), mean arterial pressure (74.4�2.4 mm Hg versus 66.2�2.5 mm Hg;
P
<0.001), and left atrial pressure (23.3�1.0 mm Hg versus 18.8�1.3 mm Hg;
P
<0.001). AM2 administration also induced significant elevations in plasma cAMP (
P
<0.01) in association with rises in atrial (
P
<0.05) and brain (
P
<0.01) natriuretic peptides and plasma renin activity (
P
<0.01). Despite the increase in renin activity, plasma aldosterone levels were not significantly altered, whereas the aldosterone/plasma renin activity ratio was reduced (
P
=0.08). Plasma vasopressin, endothelin-1, and catecholamines levels were also unchanged by AM2. Renal effects of AM2 included increased excretion of sodium (
P
<0.05), cAMP (
P
<0.01), and creatinine (
P
<0.05), with augmented creatinine clearance (
P
<0.05), and a trend for urine output to rise (
P
=0.068).

Conclusion—

These results indicate that AM2 administration has favorable effects on cardiovascular, endocrine, and renal indexes in heart failure and identify the peptide as a potential therapeutic target in this disease.
Heart Failure Care in the Outpatient Cardiology Practice Setting
Authors: Fonarow Gregg C. , Yancy Clyde W. , Albert Nancy M. , Curtis Anne B. , Stough Wendy Gattis , Gheorghiade Mihai , Heywood J. Thomas , McBride Mark L. , Mehra Mandeep R. , O'Connor Christopher M. , Reynolds Dwight , Walsh Mary Norine
Published: May 2008

Background—

Few data exist regarding contemporary care patterns for heart failure (HF) in the outpatient setting. IMPROVE HF is a prospective cohort study designed to characterize current management of patients with chronic HF and ejection fraction ≤35% in a national registry of 167 US outpatient cardiology practices.

Methods and Results—

Baseline patient characteristics and data on care of 15381 patients with diagnosed HF or prior myocardial infarction and left ventricular dysfunction were collected by chart abstraction. To quantify use of therapies, 7 individual metrics (use of angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, β-blocker, aldosterone antagonist, anticoagulation, implantable cardioverter defibrillator, cardiac resynchronization therapy, and HF education) and composite metrics were assessed. Care metrics include only patients documented to be eligible and without contraindications or intolerance. Among practices, 69% were nonteaching. Patients were 71% male, with a median age of 70 years, and a median ejection fraction of 25%. Use of angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (80%) and β-blocker (86%) was relatively high in eligible patients in the outpatient cardiology setting; other metrics, such as aldosterone antagonist (36%), device therapy (implantable cardioverter defibrillator/cardiac resynchronization therapy with defibrillator, 51%; cardiac resynchronization therapy, 39%), and education (61%), showed lower rates of use. A median 27% of patients received all HF therapies for which they were potentially eligible on the basis of chart documentation. Use of guideline-recommended therapies by practices varied widely.

Conclusions—

These data are among the first to assess treatment in the outpatient setting since the release of the latest national HF guidelines and to demonstrate substantial variation among cardiology practices in the documented therapies provided to HF patients.
Time Course of Early Audiovisual Interactions during Speech and Nonspeech Central Auditory Processing: A Magnetoencephalography Study
Authors: Hertrich Ingo , Mathiak Klaus , Lutzenberger Werner , Ackermann Hermann
Published: May 2008

Cross-modal fusion phenomena suggest specific interactions of auditory and visual sensory information both within the speech and nonspeech domains. Using whole-head magnetoencephalography, this study recorded M50 and M100 fields evoked by ambiguous acoustic stimuli that were visually disambiguated to perceived /ta/ or /pa/ syllables. As in natural speech, visual motion onset preceded the acoustic signal by 150 msec. Control conditions included visual and acoustic nonspeech signals as well as visual-only and acoustic-only stimuli. (a) Both speech and nonspeech motion yielded a consistent attenuation of the auditory M50 field, suggesting a visually induced “preparatory baseline shift” at the level of the auditory cortex. (b) Within the temporal domain of the auditory M100 field, visual speech and nonspeech motion gave rise to different response patterns (nonspeech: M100 attenuation; visual /pa/: left-hemisphere M100 enhancement; /ta/: no effect). (c) These interactions could be further decomposed using a six-dipole model. One of these three pairs of dipoles (V270) was fitted to motion-induced activity at a latency of 270 msec after motion onset, that is, the time domain of the auditory M100 field, and could be attributed to the posterior insula. This dipole source responded to nonspeech motion and visual /pa/, but was found suppressed in the case of visual /ta/. Such a nonlinear interaction might reflect the operation of a binary distinction between the marked phonological feature “labial” versus its underspecified competitor “coronal.” Thus, visual processing seems to be shaped by linguistic data structures even prior to its fusion with auditory information channel.
The Attentional Blink Modulates Activity in the Early Visual Cortex
Authors: Hein Grit , Alink Arjen , Kleinschmidt Andreas , Müller Notger G.
Published: May 2008

The attentional blink (AB) documents a particularly strong case of visual attentional competition, in which subjects' ability to identify a second target (T2) is significantly impaired when it is presented with a short SOA after a first target (T1). We used functional magnetic resonance imaging to investigate the impact of the AB on visual activity in individually defined retinotopic representations of the target stimuli. Our results show reduction of neural response in V3 and marginally in V2 and V1, paralleling the behavioral AB effect. Reduction of visual activity was accompanied by reduced neural response in the inferior parietal cortex. This indicates that attentional competition modulates activity in higher-order parietal regions and the early visual cortex, providing a plausible neural basis of the behavioral AB effect.
Functional Representation of Living and Nonliving Domains across the Cerebral Hemispheres: A Combined Event-related Potential/Transcranial Magnetic Stimulation Study
Authors: Fuggetta Giorgio , Rizzo Silvia , Pobric Gorana , Lavidor Michal , Walsh Vincent
Published: May 2008

Transcranial magnetic stimulation (TMS) over the left hemisphere has been shown to disrupt semantic processing but, to date, there has been no direct demonstration of the electrophysiological correlates of this interference. To gain insight into the neural basis of semantic systems, and in particular, study the temporal and functional organization of object categorization processing, we combined repetitive TMS (rTMS) and ERPs. Healthy volunteers performed a picture–word matching task in which Snodgrass drawings of natural (e.g., animal) and artifactual (e.g., tool) categories were associated with a word. When short trains of high-frequency rTMS were applied over Wernicke's area (in the region of the CP5 electrode) immediately before the stimulus onset, we observed delayed response times to artifactual items, and thus, an increased dissociation between natural and artifactual domains. This behavioral effect had a direct ERP correlate. In the response period, the stimuli from the natural domain elicited a significant larger late positivity complex than those from the artifactual domain. These differences were significant over the centro-parietal region of the right hemisphere. These findings demonstrate that rTMS interferes with postperceptual categorization processing of natural and artifactual stimuli that involve separate subsystems in distinct cortical areas.
An Event-related Potential Study on Changes of Violation and Error Responses during Morphosyntactic Learning
Authors: Davidson Douglas J. , Indefrey Peter
Published: May 2008

Based on recent findings showing electrophysiological changes in adult language learners after relatively short periods of training, we hypothesized that adult Dutch learners of German would show responses to German gender and adjective declension violations after brief instruction. Adjective declension in German differs from previously studied morphosyntactic regularities in that the required suffixes depend not only on the syntactic case, gender, and number features to be expressed, but also on whether or not these features are already expressed on linearly preceding elements in the noun phrase. Violation phrases and matched controls were presented over three test phases (pretest and training on the first day, and a posttest one week later). During the pretest, no electrophysiological differences were observed between violation and control conditions, and participants' classification performance was near chance. During the training and posttest phases, classification improved, and there was a P600-like violation response to declension but not gender violations. An error-related response during training was associated with improvement in grammatical discrimination from pretest to posttest. The results show that rapid changes in neuronal responses can be observed in adult learners of a complex morphosyntactic rule, and also that error-related electrophysiological responses may relate to grammar acquisition.
Predictors for Peripheral and Carotid Revascularization in a Population-Based Cohort with Type 2 Diabetes
Authors: Bosevski Marijan , Borozanov Vladimir , Tosev Slavco , Peovska Irena , Meskovska-Bongard Snezana , Georgievska-Ismail Ljubica
Published: May 2008

The study was aimed to define the predictors for peripheral and carotid revascularization in type 2 diabetic population. In all, 279 patients with type 2 diabetes and peripheral arterial disease were enrolled in a cohort longitudinal study. Study population was followed up for 24 months for the need and performance of peripheral or carotid revascularization. Logistic regression analysis was conducted to identify variables predictive of revascularization, when lipid plasma levels, glycemia, arterial hypertension, blood pressures, ankle-brachial index, intima-media thickness, body mass index, waist circumference, and hip distances were put in a model. Total cholesterol and maximal value of carotid intima-media thickness were presented as factors that independently influenced the performed peripheral revascularization. Waist circumference is defined as independent factor associated with carotid endarterectomy. Measurement of carotid intima-media thickness, waist circumference, and plasma lipid levels in type 2 diabetes with manifested peripheral and carotid arterial disease should be recommended in a manner of proper risk stratification of this population.
Percutaneous Revascularization of Grafts Versus Native Coronary Arteries in Postcoronary Artery Bypass Graft Patients
Authors: Garcia-Tejada Julio , Velazquez Maite , Hernandez Felipe , Albarran Agustín , Rodriguez Sergio , Gomez Ivan , Andreu Javier , Tascon Juan
Published: May 2008

In patients with previous coronary artery bypass graft surgery, it is unknown whether better results may be obtained with percutaneous interventions of grafts versus native arteries. The clinical outcomes in 84 patients undergoing percutaneous interventions of either grafts (n = 31) or native arteries (n = 53) were compared. Procedural success rate was 95.3% (96.8% in the graft group vs 94.4% in the native group, P = .3). Mean follow-up was 19 ± 7 months. The incidence of major adverse events was 14.2% (12.9% vs 15.1% in the graft and native groups, respectively; P = .8), mortality rate was 3.5% (6.4% vs 1.8% in the graft and native groups, respectively; P = .3), and target-lesion revascularization was performed in 4.7% (6.4% vs 3.7% in the graft and native groups, respectively, P = .6). In conclusion, both graft or native percutaneous interventions were similar for immediate and midterm clinical outcomes. The relatively low risk need for target-lesion revascularization obtained with both strategies is encouraging.
One-Year Follow-up after Implantation of the EverFlex Nitinol Stent in Long Lesions of the Superficial Femoral Artery
Authors: Ruef Johannes
Published: May 2008

For treatment of complex superficial femoral artery lesions, suitable stent devices are required. The present study details the first long-term results with the long EverFlex nitinol stent. Forty-one EverFlex stents were implanted in 32 patients with either superficial femoral artery occlusions (n = 20) or stenoses (n = 12); mean lesion length was 13.3 cm (range = 8.0–39.0). Patients presented with clinical stage Fontaine IIb (n = 27), III (n = 4), or IV (n = 1). Stent lengths were 10 cm (n = 18), 12 cm (n = 6), or 15 cm (n = 17). Follow-up after 2 months indicated primary and secondary patency rates of 96.9% (n = 31) and 100% (n = 32); ABI improved from 0.57 to 0.91 ( P < .001). After 1 year, revascularization was performed in 6 patients (18.8%). Primary and secondary patency rates were 81.3% (n = 26) and 93.8% (n = 30). In this first long-term evaluation, the long EverFlex nitinol stent achieves excellent clinical results after implantation into complex superficial femoral artery lesions.
Comparison of Quantitative Coronary Angiography with Intracoronary Ultrasound. Can Quantitative Coronary Angiography Accurately Estimate the Severity of a Luminal Stenosis?
Authors: Bourantas Christos V. , Tweddel Ann C. , Papafaklis Michail I. , Karvelis Petros S. , Fotiadis Dimitrios I. , Katsouras Christos S. , Michalis Lampros K.
Published: May 2008

In this study we investigated the accuracy of monoplane and biplane quantitative coronary angiography in estimating the luminal dimensions, using intracoronary ultrasound as gold standard. Biplane angiography and intracoronary ultrasound were performed in 24 arterial segments. The end-diastolic intracoronary ultrasound frames were manually selected and segmented. In 2 end-diastolic X ray projections, quantitative coronary angiography was performed and a novel methodology was applied to register the segmented frames onto the processed angiographic images. The luminal areas determined by quantitative coronary angiography in 1 (monoplane) and 2 projections (mean) were compared with those determined by intracoronary ultrasound. The obtained correlation coefficients for the monoplane and mean estimations were 0.69 ±0.12 and 0.77 ± 0.08 respectively. It would appear that by increasing the angle between the biplane projections, the correlation between intracoronary ultrasound and mean estimations improves. Our results provide evidence that orthogonal biplane angiography is more reliable and should be preferred to assess luminal dimensions.
Avoiding and Managing Bleeding Complications in Patients with Non-ST-Segment Elevation Acute Coronary Syndromes
Authors: Potsis Thomas Z. , Katsouras Christos , Goudevenos John A.
Published: May 2008

Antithrombotic therapy coupled with early use of cardiac catheterization and revascularization have decreased morbidity and mortality rates in patients who have acute ischemic heart disease but who carry a risk for bleeding. Bleeding complications in patients with acute coronary syndromes are associated with worse clinical outcomes, including recurrent ischemic events and death. Determining the appropriate balance between preventing ischemic events and causing bleeding in patients with acute coronary syndromes present a challenging problem for clinicians. Antithrombotics studied in recent clinical trials that have focused on bleeding reduction include bivalirudin and fondaparinux. In this review, the incidence, predictors, and clinical outcomes associated with bleeding are discussed. Furthermore, the association between antithrombotic agents and bleeding and propose strategies to prevent bleeding complications are also discussed.
Statins and Heart Failure
Authors: Filippatos Theodosios D. , Mikhailidis Dimitri P.
Published: May 2008

Retrospective studies show that statin use prevents congestive heart failure and decreases mortality in patients with congestive heart failure; however, only one prospective study is available. In the Controlled Rosuvastatin Multinational Trial in Heart Failure study, rosuvastatin (10 mg/d) was compared with placebo in patients with advanced coronary heart disease—related congestive heart failure. There was no significant difference between rosuvastatin and placebo except for hospitalization rates. Statins must be given to all patients with coronary heart disease as early as possible because they may not work in patients with advanced congestive heart failure.
Effect of 80-Hour Workweek on Continuity of Care
Authors: McBurney Patricia G. , Gustafson Kristina K. , Darden Paul M.
Published: May 2008

Work limitations were mandated (2003) to increase safety and improve resident lifestyle. Is clinic continuity affected? Medical University of South Carolina pediatric residents' records for 6 months of 2002 (before regulation) and 2003 (after regulation) were reviewed. Continuity for physician formula, t tests, and multivariate linear regression were used. Continuity was calculated for 44 residents (2002) and 45 residents (2003). Mean continuity was 54% (2002) and 53% (2003; P = .5); continuity for well-child care visits was 78% (2002) and 73% (2003; P = .047). Continuity decreased most for interns (52% [2002], 47% [2003] for all visits; 76%, 67% for well-child care visits). In the multivariate model, year did not predict continuity. When only well-child care visits were considered, year showed a trend toward significance ( P = .07): 2003 had less continuity. Compared with third-year residents, interns had 8% points less continuity for all visits (6% points less for well-child care visits). Continuity can be maintained despite regulations. Interns are most vulnerable.
Conceptualizing Instructional Leadership
Authors: Reitzug Ulrich C. , West Deborah L. , Angel Roma
Published: May 2008

Instructional leadership has long been advocated as a primary responsibility of principals. What is unclear, however, is the role that instructional leadership plays in the current high-stakes testing era in the daily work lives of principals, how they practice as instructional leaders, and toward what instructional outcomes they strive. This study focused on how principals understand the relationship between their daily work and the improvement of instruction in their schools. The study incorporates the voices of 20 principals. Multiple conceptions of instructional leadership are identified and problematic aspects of these conceptions are discussed.