bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detection and characterization of breast tumours by time-domain scanning optical mammography
Authors: Rinneberg H. , Grosenick D. , Moesta K. , Wabnitz H. , Mucke J. , Wübbeler G. , Macdonald R. , Schlag P. 
Published: March 2008

AbstractThe paper gives a short overview of various methods of optical mammography, emphasizing scanning time-domain mammography. The results of a clinical study on time-domain optical mammography are reviewed, comprising 154 patients carrying a total of 102 carcinomas validated by histology. A visibility score attributed to each carcinoma as qualitative measure of tumour detectability indicates acceptable sensitivity but poor specificity for discrimination between malignant and benign lesions. Likewise, a multi-variate statistical analysis yields sensitivity and specificity between 80% and 85% for tumour detection and discrimination with respect to normal (healthy) breast tissue, but values less than 70% for discrimination between malignant and benign breast lesions, being too low to be of clinical relevance. For 87 of the 88 tumours detected retrospectively in both projection optical mammograms, optical properties and tissue parameters were derived based on the diffraction of photon density waves by a spherical inhomogeneity as forward model. Following injection of a bolus of indocyanine green as non-targeted absorbing contrast agent, dynamic contrast-enhanced time-domain optical mammography was carried out on a small number of patients, but no differences in wash-out kinetics of indocyanine green between tumours and healthy breast tissue were observed.
Infrared sensors in spacecraft that monitor planet Earth
Authors: Norton P. 
Published: March 2008

AbstractInfrared sensors provide a backbone for many of the instruments flown by National Aeronautics and Space Administration (NASA) and National Oceanic and Atmospheric Administration (NOAA) that monitor conditions on planet Earth. This paper gives an overview of some of those missions and infrared sensors used in the spacecraft instruments. Basic properties of the sensors are described and the evolution of sensor complexity is presented by example. Future trends pointing towards more sophisticated sensors in the future are discussed.
On the Alexandroff decomposition theorem
Authors: Avallone Anna , Barbieri Giuseppina , Vitolo Paolo 
Published: March 2008

Abstract
We prove an Alexandroff decomposition type theorem, which extends a decomposition theorem proved in [de LUCIA, P.—MORALES, P.: Decomposition of group-valued measures in orthoalgebras, Fund. Math. 158 (1998), 109–124].
Experimental and modeling study of catalytic reaction of glucose isomerization: Kinetics and packed‐bed dynamic modeling
Authors: Dehkordi Asghar Molaei , Safari Iman , Karima Muhammad M. 
Published: March 2008

AbstractThe kinetics and equilibrium of isomerization reaction of D‐glucose to D‐fructose have been investigated using a commercial immobilized glucose isomerase (IGI), Sweetzyme type IT®, in a batch stirred‐tank reactor. The batch experimental data were used to model the reaction kinetics using the well‐known Michaelis–Menten rate expression. The kinetic model was utilized in a dynamic‐mathematical model for a packed‐bed reactor to predict the concentration profiles of D‐glucose and D‐fructose within the reactor. The experimental results for the fractional conversion of D‐glucose in the packed‐bed reactor of IGI catalyst indicated that the model prediction of the transient and steady‐state performance of the packed‐bed reactor was satisfactory and as such could be used in the design of a fixed‐bed IGI catalytic reactor. Moreover, the influences of axial mixing term, particle Re number, and axial peclet number (Pea) on the performance capability of the packed‐bed reactor of IGI catalyst were investigated. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Drops, slugs, and flooding in polymer electrolyte membrane fuel cells
Authors: Kimball Erin , Whitaker Tamara , Kevrekidis Yannis G. , Benziger Jay B. 
Published: March 2008

AbstractThe process of flooding has been examined with a single‐channel fuel cell that permits direct observation of liquid water motion and local current density. As product water flows through the largest pores in the hydrophobic GDL, drops detach from the surface, aggregate, and form slugs. Flooding in polymer electrolyte membrane (PEM) fuel cells occurs when liquid water slugs accumulate in the gas flow channel, inhibiting reactant transport. Because of the importance of gravity, we observe different characteristics with different orientations of the flow channels. Liquid water may fall away from the GDL and be pushed out with minimal effect on the local current density, accumulate on the GDL surface and cause local fluctuations, or become a pulsating flow of liquid slugs and cause periodic oscillations. We show that flooding in PEM fuel cells is gravity‐dependent and the local current densities depend on dynamics of liquid slugs moving through the flow channels. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Experimental study on a new process of producing hydrogen in consumption of water and coal
Authors: Zhou Yaping , Jia Chunxiao , Zhang Yu , Liu Chunfeng , Huang Desheng , Sun Yan , Zhou Li 
Published: March 2008

AbstractA new process of producing pure H2 in consumption of H2O and carbon is presented. It contains three reactions: (1) Steam reacts with FeO at 800°C generating pure H2 and Fe3O4/Fe2O3; (2) Fe3O4/Fe2O3 are reduced to FeO by CO at same temperature while CO changes to CO2; (3) The produced CO2 reacts with carbon generating CO at 900°C. The net product of the process is H2 and CO. Theoretical energy gain of the new process is much higher than 1.0 and is energetically more than autarky. Some CO satisfies the process energy requirement and the surplus CO outputs as by‐product. Experiments proved the feasibility of the process with indication of the importance to control the extent of reduction. The prominent advantages embedded allow the process applied in large‐scale to trade coal for hydrogen. As such, instead of burning coal, hydrogen is burnt wherever energy is consumed. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Cross‐sectional analysis of long bones, occupational activities and long‐distance trade of the Classic Maya from Xcambó—Archaeological and osteological evidence
Authors: Maggiano Isabel S. , Schultz Michael , Kierdorf Horst , Sosa Thelma Sierra , Maggiano Corey M. , Tiesler Blos Vera 
Published: March 2008

AbstractXcambó is a Classic period Maya site (250–700 AD) situated on the northern coast of Yucatan, Mexico. Archaeological evidence suggests that the site began as a salt production center but adopted a more administrative role as a commercial port in the Late Classic period. Economic growth, depending on its magnitude, could have affected the daily occupations of Xcambó's inhabitants. However, this is difficult to infer from the archaeological record. The aim of this study was to directly evaluate this possibility through skeletal analysis. Since diaphyseal robusticity and shape are predominantly influenced by mechanical loading history, long bone cross‐sections can be used to access activity patterns. To this end, humeri and femora of 47 male and 35 female adult specimens from two Xcambó population samples were scrutinized. Our analysis satisfies general archaeological expectations and provides additional information on the population's physical response to economic growth. Decreasing robusticity and femoral anterior–posterior rigidity indicate an overall decrease in physical workload and mobility, concomitant with the site's increasing administrative function. We also observed a significant decrease in sexual dimorphism, possibly attributable to the differential response of male and female physical work spheres during socioeconomic change. In general, our findings suggest even nonsubsistence based socioeconomic change can significantly affect the bone structure of a population, rendering activity analysis an important aspect of the reconstruction of living conditions of past populations. Am J Phys Anthropol, 2008. © 2008 Wiley‐Liss, Inc.
A Heterogeneous‐Catalyst‐Based, Microwave‐Assisted Protocol for the Synthesis of 2,2′‐Bipyridines
Authors: Moore Lucas R. , Vicic David A. 
Published: March 2008

AbstractA new method of preparing 2,2′‐bipyridines with short reaction times by using microwave assistance and heterogeneous catalysts has been developed. With a Negishi‐like protocol, it was found that Ni/Al2O3–SiO2 afforded 2,2′‐bipyridine products in up to 86 % yield in 1 h. Palladium supported on alumina also provided yields of 2,2′‐bipyridines comparable to those seen for homogeneous PEPPSITM (1,3‐diisopropylimidazol‐2‐ylidene)(3‐chloropyridyl)palladium(II)dichloride) and tetrakis(triphenylphosphanyl)palladium complexes.
Intuitive prediction: ecological validity versus representativeness
Authors: Cahan Sorel , Snapiri Tchia 
Published: March 2008

AbstractInsufficiently regressive intuitive predictions have been attributed to mistaken reliance on the representativeness heuristic. In contrast, we suggest that intuitive predictions stem from a conceptualization of ‘goodness of prediction’ that differs from the accepted statistical definition in terms of error minimization, namely, ecological validity—that is, representation of the substantive characteristics of the predicted variable Y and its distribution as well as of the relationship between Y and the predictor X—rather than minimization of prediction errors. Simultaneous satisfaction of the above representation requirements is achieved by multivalued prediction: The prediction of different Y′ values for the same X value, resulting in conditional distributions Y′|X for at least some X values. Empirical results supporting this hypothesis are presented and discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Detrimental effects of tobacco smoke exposure during development on postnatal lung function and asthma
Authors: Wang Lei , Pinkerton Kent E. 
Published: March 2008

AbstractExposure to environmental tobacco smoke (ETS) during fetal development and early postnatal life is perhaps the most ubiquitous and hazardous of children's environmental exposures. The developing lung is highly susceptible to ETS. A large body of literature links both prenatal maternal smoking and children's ETS exposure to decreased lung growth. This review summarizes the state of the knowledge, including both human epidemiology and laboratory animal experiments, linking ETS, lung development, and respiratory outcomes. Important issues discussed include lung development and lung function and asthma in relation to ETS exposure during critical windows of growth. Prenatal exposure to ETS is associated with impaired lung function and increased risk of developing asthma, whereas postnatal exposure mainly acts to trigger respiratory symptoms and asthma attacks, but it also plays an important role in the occurrence of asthma in children. This review provides evidence that avoidance of ETS exposure both before and after birth is beneficial to long‐term respiratory health, because airway function in later life is believed to be largely determined by lung development occurring in utero and in early infancy. Birth Defects Research (Part C) 84:54–60, 2008. © 2008 Wiley‐Liss, Inc.
Insulin‐like growth factor‐induced signals activate mitochondrial respiration
Authors: Unterluggauer Hermann , Hütter Eveline , Viertler Hans‐Peter , Jansen‐Dürr Pidder 
Published: March 2008

AbstractFrom experiments with lower eukaryotes it is known that the metabolic rate and also the rate of aging are tightly controlled by the insulin‐like growth factor (IGF)/insulin signal transduction pathway. The mitochondrial theory of aging implies that an increased metabolic rate leads to increased mitochondrial activity; increased production of reactive oxygen species due to these alterations would speed up the aging process. To address the question if mitochondrial activity is influenced by insulin/IGF signaling, we have established an experimental system to determine the influence of IGF‐I‐dependent signaling on mitochondrial function. We used DU145 prostate cancer cells, known for the intact IGF signal transduction pathway, to address the influence of IGF receptor activation on mitochondrial function by high‐resolution respirometry. These experiments revealed that indeed mitochondrial function is regulated by IGF signaling, and up‐regulation of respiration seems to require phosphoinositide 3‐kinase/AKT signaling, but is independent of IGF effects on cell cycle progression. Collectively these data establish a regulatory cross‐talk between insulin/IGF signal transduction and mitochondrial function, two major pathways implicated in controlling the rate of aging.
Management of patients with refractory migraine and PFO: Is MIST I Relevant?
Authors: Tobis Jonathan 
Published: March 2008

AbstractThe results of the randomized clinical trial entitled: Migraine Intervention with Starflex Technology (MIST), produced surprising and disappointing results on the effect of PFO closure to decrease migraine headaches. There have been allegations of misrepresentation of the effectiveness of this device. These issues have significant implications in how randomized clinical trials are performed that will impact current and future planned trials of PFO closure to treat migraine headaches. © 2008 Wiley‐Liss, Inc.
Percutaneous revascularization of subclavian artery chronic occlusion with dual cerebral artery protection
Authors: Shah Nehal , Nee Lisa M. , Raval Amish N. 
Published: March 2008

AbstractPercutaneous intervention for symptomatic subclavian artery chronic occlusion is an occasionally performed, minimally invasive alternative to surgical bypass. Potential complications include stroke, perforation, and recanalization failure. We discuss a case of successful percutaneous revascularization of symptomatic subclavian artery chronic occlusion using coronary devices and dual cerebral embolic protection. © 2008 Wiley‐Liss, Inc.
Color‐coded duplex ultrasound for diagnosis of renal artery stenosis and as follow‐up examination after revascularization
Authors: Zeller Thomas , Bonvini Robert F. , Sixt Sebastian 
Published: March 2008

AbstractCurrently, angiography is still considered to be the gold standard for the diagnosis of a renal artery stenosis (RAS). However, angiography is invasive and carries the potential risk of haematoma, pseudoaneurysm, contrast agent induced nephropathy, and athermanous embolization. Color‐coded duplex ultrasound is a noninvasive frequently repeatable bed‐side examination and is currently the only diagnostic method to reliably differentiate between a hemodynamically relevant or irrelevant stenosis using the side‐to‐side difference of the intrarenal resistance index (RI). There is a highly specific correlation between a side difference of the RI of >0.05 and an at least 70% angiographic diameter stenosis. All other duplex parameters like a peak systolic flow velocity >200 cm/sec or a renal aortic flow velocity ratio >3.5 are correlated to a 50 or 60% angiographic diameter stenosis and offer therefore indeed a high sensitivity in terms of detecting a RAS; however, the specificity detecting a hemodynamically relevant RAS is low. Provided that duplex ultrasound is performed by an experienced physician with an adequate machine it should be the preferred imaging method. The present article gives an overview about the literature related to duplex based diagnosis of RAS and as a follow‐up diagnostic procedure following RAS revascularization. © 2008 Wiley‐Liss, Inc.
Percutaneous transthoracic ventricular puncture for diagnostic and interventional catheterization
Authors: Lim D. Scott , Ragosta Michael , Dent John M. 
Published: March 2008

AbstractObjective: To describe our experience in a case series of patients requiring percutaneous direct ventricular puncture and sheath placement for diagnosis or intervention. Background: Access to the right or left ventricle for percutaneous interventions is limited in patients with mechanical prostheses in either the tricuspid, or mitral and aortic positions. Methods: After coronary angiography, direct ventricular puncture under ultrasound and fluoroscopic guidance was performed. At end of case, protamine was given to reverse the heparin, and sheaths were pulled with purse‐string suture closure of the skin entrance. Results: For right ventricular access, 8‐ to 9‐F sheaths were placed from subxiphoid approach in 2 patients to allow conduit and pulmonary artery interventions. For left ventricular access in patients with mitral and aortic prostheses, 4‐ to 8‐F sheaths were placed from apical approach to allow diagnostic evaluation in 1 and interventions in 5 to occlude perivalvular mitral leaks and postoperative ventricular septal defect. Complication in one consisted of intercostal vein injury resulting in hemothorax requiring chest tube drainage. Conclusion: In this small cases series, direct ventricular puncture allowed the intervention to proceed with up to 9‐F sheath size. Attention to puncture site relative to intercostal vascular anatomy is warranted. © 2008 Wiley‐Liss, Inc.
Hybrid balloon pulmonary valvuloplasty in a 700‐g infant: Thinking outside the box
Authors: Holzer Ralf J. , Sisk Matt , Phillips Alistair 
Published: March 2008

AbstractThis report describes a unique Hybrid approach to balloon pulmonary valvuloplasty in a 700‐g premature infant with pulmonary valve stenosis and very poor right ventricular function. © 2008 Wiley‐Liss, Inc.
Percutaneous removal of an embolized port catheter: Description of a new coaxial recovery technique including a case‐report
Authors: Burzotta Francesco , Romagnoli Enrico , Trani Carlo 
Published: March 2008

AbstractThe achievement of coaxiality between recovery device and embolized tubular foreign bodies like central venous catheters is a key point to achieve percutaneous removal. To facilitate this target, we designed a coaxial retrieval loop‐snare device using amodified coronary guiding catheter and a coronary 0.014″ guidewire. This new technique has been bench tested and then successfully used to remove a long Port‐A catheter's fragment embolized into the right sided heart. © 2008 Wiley‐Liss, Inc.
Synthesis and Complexation of Multiarmed Cycloveratrylene‐Type Ligands: Observation of the “Boat” and “Distorted‐Cup” Conformations of a Cyclotetraveratrylene Derivative
Authors: Sumby Christopher J. , Gordon Keith C. , Walsh Tim J. , Hardie Michaele J. 
Published: March 2008

AbstractInvestigations of a previously reported ligand, hexakis(2‐pyridylmethyl)cyclotricatechylene (1), and a new tetrameric bridging ligand, octakis(2‐pyridylmethyl)cyclotetracatechylene (2), the latter constructed on a larger cyclotetraveratrylene (CTTV) scaffold, are described. Variable‐temperature NMR studies support a “sofa” conformation for 2, akin to studies on the parent compound. The coordination chemistry of 2 and its smaller trimeric homologue have also been investigated with silver(I), copper(II) and palladium(II) salts. An unexpected chelating mode was observed for 1 in the structure of DMF⊂[Pd3Cl6(1)]⋅DMF, whereby the palladium cations bridge two veratrole subunits rather than chelating within a single subunit. In the structure of [Ag4(2)][Co(C2B9H11)2]4⋅2.8 CH3CN⋅ H2O, ligand 2 adopts a “boat” conformation, whereas in [Pd4Cl8(2)]⋅4 H2O, 1H NMR spectroscopic studies and calculations indicate that the ligand is present in a previously unobserved “distorted‐cup” conformation. This conformation was calculated to be approximately 90 kJ mol−1 lower in energy than the alternative “sofa” conformation. Thus, coordination‐induced conformational control over CTTV derivatives offers new routes to exploit the host–guest chemistry of these compounds.
The online assignment of the absolute configuration of natural products: HPLC‐CD in combination with quantum chemical CD calculations
Authors: Bringmann Gerhard , Gulder Tobias A.M. , Reichert Matthias , Gulder Tanja 
Published: March 2008

AbstractThe application of modern online methods, e.g., HPLC‐MS/MS and HPLC‐NMR, allows the elucidation of constitutions and relative configurations of new natural products directly from crude extracts. To additionally establish the full absolute configurations of such secondary metabolites without the necessity of first isolating the compounds, we have introduced HPLC‐CD coupling (CD = circular dichroism) into natural product analysis, taking advantage of the different chiroptical properties of stereoisomers, in particular of enantiomers. In combination with quantum chemical CD calculations this method allows the stereochemical characterization of (even structurally unprecedented) chiral molecules, thus avoiding the—often risky—merely empirical assignment by comparison with the CD spectra of related compounds with known absolute stereostructures, or by other methods such as, e.g., the exciton chirality approach. This review presents the experimental requirements for the hyphenation and the theoretical background of the calculation of UV and CD spectra, which is then exemplified by some recent HPLC‐CD applications to the elucidation of absolute configurations of most diverse compounds of mainly natural origin. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Systolic Function as a Predictor of Mortality and Quality of Life in Long‐term Survivors with Heart Failure
Authors: McNamara Robert L. , Austin Bethany A. , Wang Yongfei , Smith Grace L. , Vaccarine Viola , Krumholz Harlan M. 
Published: March 2008

AbstractBackgroundPatients with heart failure (HF) and preserved ejection fraction (EF) have been shown to have high mortality rates, comparable to those with reduced EF. Thus, long‐term survivors of HF, regardless of ejection fraction, are a select group. Little is known about disease‐related quality of life (QOL) and health status in these patients.HypothesisPreserved EF in patients with heart failure independently predicts long‐term survival, health related quality of life (QOL), or functional status.MethodsThe study followed a cohort of 413 patients consecutively hospitalized for HF between March 1996 and September 1998. In July 2005, information was collected about their mortality, health related QOL as defined by disease‐specific Kansas City Cardiomyopathy Questionnaire (KCCQ) scores, and functional decline as defined by limitations in Activities of Daily Living (ADL) scores.ResultsThe primary outcomes were mortality, QOL, and functional decline. At follow‐up, 8.1 years after enrollment, overall mortality was 76% (314/413). Adjusted for age, gender, renal insufficiency, diabetes mellitus, hypertension, HF, and respiratory disease, those with decreased ejection fraction (EF < 40%) had higher mortality compared with those with preserved ejection fraction (hazard ratio [HR] 1.42; confidence interval [CI] = 1.13, 1.80, p = 0.003). The KCCQ scores, including Clinical Summary Scores and Symptom Limitation Scores, as well as ADL limitations, were not significantly different in the survivors with preserved or decreased EF.ConclusionsHeart failure patients with preserved EF have a modest survival advantage compared with those with decreased EF, but health related QOL scores and functional decline in survivors are similar regardless of systolic function. Copyright © 2008 Wiley Periodicals, Inc.