bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scintiphotographic Evaluation of Patients with Suspected Left Ventricular Aneurysm
Authors: RIGO PIERRE , MURRAY MALCOLM , STRAUSS H. WILLIAM , PITT BERTRAM 
Published: June 2012

Twenty-two patients with a history of myocardial infarction and suspected of having a left ventricular aneurysm were evaluated by routine clinical studies, gated cardiac blood pool scanning, and contrast left ventriculography.
Thirteen patients were found to have a localized left ventricular aneurysm and nine demonstrated diffuse left ventricular hypokinesis on contrast angiography. The patients with localized left ventricular aneurysms could not be separated from those with diffuse left ventricular hypokinesis on the basis of the routine clinical evaluation including the chest roentgenogram or the finding of ST-segment elevation in the electrocardiogram. Scintiphotographic studies identified the nine with diffuse hypokinesis and twelve of the thirteen with a localized left ventricular aneurysm. In one patient with a calcified left ventricular aneurysm filled with clot, the cardiac blood pool scan showed an area of akinesis which corresponded to that seen on contrast angiography, but the aneurysm could not be detected.

In nineteen of the patients in whom adequate measurements were obtained, left ventricular end-diastolic volume and ejection fraction by both contrast angiography and gated cardiac blood pool scintiphotography demonstrated a good correlation,
r
= 0.92 and 0.87, respectively. There was also a good correlation between the extent of left ventricular akinesis seen on contrast angiography and gated scintiphotography,
r
= 0.97.

This study demonstrates that biplane gated cardiac blood pool scans are useful in differentiating patients with localized left ventricular aneurysms from those with diffuse left ventricular hypokinesis.
Long-term Changes of Serum Cholesterol with Cholesterol-altering Drugs in Patients with Coronary Heart Disease
Authors: DETRE KATHERINE M. , SHAW LAWRENCE 
Published: June 2012

In a controlled secondary prevention trial of estrogen and cholesterol-lowering drugs on 570 veterans, all of whom had had one or more episodes of acute myocardial infarction, changes in serum cholesterol were followed for at least five years. The findings included the following:
1) Estrogen, 1.25 mg daily, had no appreciable effect on cholesterol level.
2) Aluminum nicotinate, 4 g/day, resulted in a 20% reduction in cholesterol level for about 2½ years after which levels slowly rose to a level 12% below the baseline level in good adherers; poor adherers had smaller ultimate changes.
3) Dextrothyroxine, 4 mg/day, had a sustained cholesterol-lowering effect of approximately 7% throughout the study.
The above values were obtained after adjusting for an underlying upward trend in all cholesterol values during the five-year observation period.
4) Discontinuation of both aluminum nicotinate and dextrothyroxine resulted in a significant rise in cholesterol within three months.
5) The 6% rise in the cholesterol level found in the control group over five years of follow-up could be attributed to aging and laboratory drift.
6) Regression toward the mean rather than pharmacological effect accounted for the greater response to treatment of patients with high initial cholesterol.
Deductive Echocardiographic Analysis in Infants with Congenital Heart Disease
Authors: SOLINGER ROBERT , ELBL FRANCISCO , MINHAS KAREEM 
Published: June 2012

A step-by-step approach to cardiac diagnosis utilizing a chest X-ray and echocardiography is described and used to study a normal infant and six infant patients with angiocardiographically-proven complex congenital heart malformations.
The heart is divided into three major anatomical segments in order to localize the atrial and ventricular chambers and determine the relationship of the great arteries. The atrial chambers are localized by noting the position of the liver on the X-ray. The right atrium is on the same side as the liver with few exceptions. The ventricular chambers are localized by echocardiographically identifying the tricuspid and mitral valves. They are a part of the morphologically right and left ventricles, respectively. As a general rule, the atrioventricular valve whose anterior leaflet is continuous with the posterior margin of a semilunar valve is the mitral valve. The atrioventricular valve whose anterior leaflet is not continuous with a posterior semilunar valve margin is the tricuspid valve. When the tricuspid valve is to the right of the mitral valve, the ventricles are in their normal positions (ventricular d-loop); when it is to the left, the ventricles are inverted (ventricular l-loop). The relationship of the great arteries is determined by echocardiographically identifying the semilunar valves and noting their positions relative to each other, the interventricular septum and the ventricular chambers. In a ventricular d-loop, the aortic valve is usually to the right of the pulmonary valve. In a ventricular l-loop, the opposite is true. As much as a 17% error may exist when transposition of the great arteries is a component of the malformation. Therefore, as additional aids in semilunar valve identification the R-C intervals of the valves (interval between R wave of electrocardiogram and valve closure on echogram) and outside diameters of the valve roots are measured. Usually the R-C interval is longer and, in the absence of pulmonary stenosis, the outside diameter greater for the pulmonary valve. The segmental diagnoses are then combined to obtain the "type" of heart, and a careful search is made for associated defects.
Using this approach, the positions of the atrial and ventricular chambers and the relationship of the great arteries were accurately determined in the six complex cardiac malformations studied.
Familial Atrial Dysrhythmia with A-V Block
Authors: AMAT-Y-LEON FERNANDO , RACKI ANTHONY J. , DENES PABLO , EICK ROBERT E. TEN , SINGER DONALD H. , BHARATI SAROJA , LEV MAURICE , ROSEN KENNETH M. 
Published: June 2012

This study is of a family with a syndrome of atrial fibrillation or flutter with advanced or complete atrioventricular (A-V) block, involving four members in two generations. Less serious arrhythmias were documented in another 15 members (three generations). Inheritance was by autosomal dominance with varying degrees of expression. An atrial biopsy was obtained in one of the members, a 40-year-old female who had atrial flutter with advanced A-V block proximal to the His bundle (H-V interval of 39 msec). Intracellular action potential (IAP) recordings from this tissue revealed: 1) partially depolarized cells with depressed IAP amplitude, 2) phase IV diastolic depolarization with spontaneous firing, 3) diminished excitability and responsiveness, and 4) decremental conduction with local block and re-entry. Histological findings revealed vacuolar degeneration, hypertrophy, and early necrosis of atrial cells.
In conclusion, the multiple IAP and pathologic abnormalities provide a basis for atrial dysrhythmia in this family. The etiology of the disease is unknown.
Thrombo-embolism in Acute and in Healed Myocardial Infarction
Authors: MILLER R. DREW , JORDAN ROBERT A. , PARKER ROBERT L. , EDWARDS JESSE E. 
Published: June 2012

The purpose of this investigation was to study the incidence and location of systemic arterial occlusion and pulmonary embolism in a consecutive series of cases of fatal acute myocardial infarction. Another consecutive series of cases in which healed myocardial infarction was demonstrated at necropsy was similarly studied. In none of the cases included in this study had anticoagulant therapy been employed.
Massive pulmonary embolism was the most frequent fatal thrombo-embolic complication found among the cases of acute myocardial infarction. Cerebral infarction was the most frequent fatal thrombo-embolic complication found among the cases of healed myocardial infarction. Cerebral infarction was the most frequent fatal systemic arterial thrombo-embolic lesion in both groups. Acute splenic and renal infarcts were frequently demonstrated but with one exception appeared to play an incidental role in the clinical course of the patients. Although systemic arterial occlusion was frequently found in association with intracardiac mural thrombi, there were many other cases in which evidence of systemic arterial occlusion was found in the absence of intracardiac mural thrombi. A positive correlation existed between the presence of pulmonary and systemic arterial occlusion and the occurrence of congestive cardiac failure.
The Treatment of Chronic Cor Pulmonale
Authors: HARVEY RÉJANE M. , FERRER M. IRENÉ , COURNAND ANDRÉ 
Published: June 2012

In this presentation stress has been laid upon the concept that the treatment, as well as the prognosis of chronic cor pulmonale depend upon the underlying pulmonary disease. It has long been known that the chief causes of chronic cor pulmonale are chronic obstructive pulmonary emphysema and various forms of fibrosis, particularly the pneumoconioses. An understanding of the difference between these diseases, both as to their pulmonary dysfunction and their circulatory complications, is crucial to success in therapy. Management of the patient with chronic pulmonary emphysema and (or pulmoniale is quite different from that of the subject with fibrosis and right heart involxemenit.
Unfortuniately, little as yet is known about the circulation in the pulmonary fibroses. In patients with pulmonary fibrosis as well as those with granulomas of the lung it would appear that the anatomic pulmonary lesion is chiefly responsible for the pulmonary hypertension, in contradistinction to the patients with emphysema. Inasmuch as the anatomic lesions are for the most part irreversible, so is the pulmonary hypertension. This has limited our therapeutic approach in this form of chronic cor pulmonale to rigorous restriction of physical activity directed at minimizing exacerbations of pulmonary hypertension.
While emphasis has been placed upon the difference in management of the patient with emphysema or fibrosis and cor pulmonale, nonetheless it should be remembered that in any individual patient these two conditions may coexist. In that event, intensive therapy directed at the sequellae of emphysema may be very rewarding.
The Heart in Anemia
Authors: PORTER WILLIAM B. , JAMES G. WATSON 
Published: June 2012

The following brief summary seems justified from the large volume of accumulated data dealing with the reaction of the cardiovascular system in the anemic patient.
There are four mechanisms operating in the anemic patient which may increase the supply of oxygen to the tissues when the oxygen carrying capacity of the blood is reduced. Under conditions of rest, a rapid velocity flow and tachycardia with an increase in minute volume of cardiac output is the first response to anemia. As compensation develops, tachycardia and increased velocity flow are largely replaced by selective shunting of blood and the removal of an increasing percentage of oxygen in the tissue capillaries from each gram of circulating hemoglobin.
These later physiologic mechanisms are best illustrated by patients with chronic parasitic anemias. Under conditions of physical stress each of the four physiologic mechanisms contribute in meeting the demands for increased oxygen requirements. Compensation is, however, never perfect; the status of the patient is determined by the reduction in hemoglobin, the tissue oxygen requirements, the presence of physical changes in the cardiovascular and pulmonary systems, degree of oxygen abstraction from the blood, and the selective shunting of blood.
In relatively acute anemia, dyspnea readily occurs on physical exercise. Reduction in the ventilatory capacity of the lung occurring in some anemic patients results from an over-all reduction in physical fitness due to the anemic state rather than to physical changes in the lung. In well compensated, chronic anemia, the vital capacity of the lungs is frequently above normal and similar to that observed in athletes and completely acclimatized, high altitude inhabitants.
In the absence of cardiovascular disease or physical or metabolic factors requiring increased cardiac output, true congestive heart failure rarely results from the anemic state.
Effort angina is uncommon in anemic patients and when present is usually related to underlying coronary artery disease.
Cardiac hypertrophy under certain conditions results from prolonged anemia. Since cardiac hypertrophy is rightly placed in the category of organic heart disease, one is justified in classifying chronic anemia as one of the etiologic factors in the production of heart disease.
Electrocardiographic Leads
Authors: MCFEE RICHARD , JOHNSTON FRANKLIN D. 
Published: June 2012

This paper is the first of a series of three which will deal with the relationship between the voltages in electrocardiographic leads and the electromotive forces of the heart. The general purpose of this series is to discuss various experimental and theoretic technics which can be used in the analysis of a given lead, and in the building up, or "synthesis," of leads having desired characteristics. The procedures used are based on a fundamental theorem which takes into account not only the irregular shape and conductivity of the body but also the spatial dispersion of the electromotive forces within the heart. It is closely related to the "lead vector" concept of Burger and van Milaan.
In this first paper the basic definitions and theorems are developed. The second paper discusses various methods of analysing leads. The third and last presents a number of systematic procedures for designing leads, both vectorcardiographic and unipolar. Such leads can have substantially higher accuracies than those now in use, because their design takes into account the shape and conductivity of the body and its tissues, and the eccentric and extended location of the heart.
A review of analogues of alkaline alteration with regard to long-term barrier performance
Authors: Savage D. 
Published: June 2012

AbstractCement and concrete will be used as fracture grouts, shotcrete, tunnel and borehole seals, and as matrices for waste encapsulationinter aliain geological repositories for radioactive wastes. Alteration of the host rock and/or swelling clay in waste package buffers and tunnel backfills by hyperalkaline solutions from cement/concrete may be deleterious to system performance through changes in the physicochemical properties of these barrier materials.Analogue systems (and timescales) relevant to the understanding of the alkaline disturbed zone include: industrial analogues, such as alkaline flooding of hydrocarbon reservoirs (up to 30 y), cement-aggregate reactions (up to 100 y) and the Tournemire tunnel (up to 125 y); and natural analogues, including the hyperalkaline springs at Maqarin, Jordan (more than 100,000 y), saline, alkaline lakes (more than 1,000,000 y) and certain fracture fillings in granites (more than 1,000,000 y).These systems show that alkaline alteration can be observed for thousands of years over distance scales of hundreds of metres under extreme conditions of hydraulic gradients in fractured rocks (Maqarin), but may be limited to a few centimetres over tens to a hundred years in mudstone (Tournemire). Important reaction mechanisms for retardation of alkaline fluids include: fluid mixing (alkaline oil floods, Maqarin), ion exchange (alkaline oil floods, Tournemire) and kinetic mineral dissolution-precipitation reactions (all systems studied). Qualitative and quantitative kinetic data for mineral reactions are available from cement aggregate reactions and the Searles Lake analogue, respectively. Short-term alteration observed in cement-aggregates is characterized by calcium silicate hydrate (C-S-H) minerals and incipient zeolite formation, whereas evidence from the Tournemire tunnel shows the growth of K-feldspar after relatively short time intervals (tens to a hundred years). There is a tendency for alkaline alteration to result in porosity decreases, but locally, porosity may be enhanced (e.g. near-injection well interactions in alkaline oil floods, or at fracture margins at Maqarin, Jordan). Data from industrial and natural analogues may thus supply some key data for bridging time and space scales between laboratory andin situexperiments on one hand and the requirements for safety assessment on the other.
Research and development for geological disposal of higher activity wastes: the role and expectations of the Environment Agency
Authors: Cailes C. R. , Barraclough I. , Smith R. E. , Thomson G. 
Published: June 2012

AbstractThe Environment Agency is the environmental regulator for the nuclear industry in England and Wales. We aim to ensure that any future Geological Disposal Facility (GDF) will meet our standards for protecting people and the environment during development, operation and following closure. We shall only grant an environmental permit for such a facility if the GDF developer submits an Environmental Safety Case (ESC) to the Environment Agency demonstrating that the proposed GDF will meet our standards. The ESC should be based on sound science and supported by appropriate research and development. The Environment Agency undertakes its own research programme to inform its regulatory decisions.
Sorption of Tc(IV) to some geological materials with reference to radioactive waste disposal
Authors: Hallam R. J. , Evans N. D. M. , Jain S. L. 
Published: June 2012

AbstractOne of the most important isotopes to be considered for disposal in the proposed UK Geological Disposal Facility (GDF) for higher-activity radioactive wastes will be99Tc, due to its long half-life, high fission yield and ability to migrate through the geosphere as the pertechnetate ion. Much of the Tc is likely to be in the lower Tc(IV) oxidation state due to the low Eh in the near field. Batch Tc(IV) sorption experiments have been performed from pH 3–13, using95mTc as a spike, in the presence of quartz, hematite, goethite, plagioclase feldspar, sand and shale. Solutions containing Tc(IV) were prepared at trace concentrations to avoid precipitation of TcO2. Values for the partition coefficient (Rd) were found to range from ∽4 up to ∽2 × 104cm3g–1. Rdwas heavily dependent on pH in all cases, with the highest values being found in the circumneutral area. These data will inform the performance assessment for the near-field behaviour of technetium in the UK's planned higher-activity wastes GDF. Surface complexation modelling has been performed, fitting the data using both monodentate and bidentate binding models.
Microbiological influences on fracture surfaces of intact mudstone and the implications for geological disposal of radioactive waste
Authors: Harrison H. , Wagner D. , Yoshikawa H. , West J. M. , Milodowski A. E. , Sasaki Y. , Turner G. , Lacinska A. , Holyoake S. , Harrington J. , Noy D. , Coombs P. , Bateman K. , Aoki K. 
Published: June 2012

AbstractThe significance of the potential impacts of microbial activity on the transport properties of host rocks for geological repositories is an area of active research. Most recent work has focused on granitic environments. This paper describes pilot studies investigating changes in transport properties that are produced by microbial activity in sedimentary rock environments in northern Japan. For the first time, these short experiments (39 days maximum) have shown that the denitrifying bacteria, Pseudomonas denitrificans, can survive and thrive when injected into flow-through column experiments containing fractured diatomaceous mudstone and synthetic groundwater under pressurized conditions. Although there were few significant changes in the fluid chemistry, changes in the permeability of the biotic column, which can be explained by the observed biofilm formation, were quantitatively monitored. These same methodologies could also be adapted to obtain information from cores originating from a variety of geological environments including oil reservoirs, aquifers and toxic waste disposal sites to provide an understanding of the impact of microbial activity on the transport of a range of solutes, such as groundwater contaminants and gases (e.g. injected carbon dioxide).
Potassium-bearing clinopyroxene: a review of experimental, crystal chemical and thermodynamic data with petrological applications
Authors: Safonov O. G. , Bindi L. , Vinograd V. L. 
Published: June 2012

AbstractAvailable experimental data on chemical composition and crystal structure of K-bearing clinopyroxenes are compiled together with the results of atomistic simulations and thermodynamic calculations of mineral equilibria. It is shown that the limited solubility of K2O in clinopyroxene from crustal rocks cannot be ascribed to the strong non-ideality of mixing between diopside (CaMgSi2O6) and K-jadeite (KAlSi2O6) components. The more likely reason is the instability of the potassic endmember with respect to other K-bearing phases. As the volume effects of typical K-jadeite-forming reactions are negative, the incorporation of K in the clinopyroxene structure becomes less difficult at higher pressure. Atomistic simulations predict that the thermodynamic mixing properties of diopside-K-jadeite solid-solutions at high temperature approach those of a regular mixture with a relatively small positive excess enthalpy. The standard enthalpy of formation(ΔfH° =—2932.7 kJ/mol), the standard volume(V° =6.479 J mol–1bar–1) and the isothermal bulk modulus(K0=145 GPa) of K-jadeite were calculated from first principles, and the standard entropy(S°= 141.24 J mol–1K–1) and thermal-expansion coefficient (α = 3.3 x 1CP–5K–1) of the K-jadeite endmember were estimated using quasi-harmonic lattice-dynamic calculations based on a force-field model. The estimated thermodynamic data are used to compute compositions of K-bearing clinopyroxenes in diverse mineral assemblages within a wideP-Tinterval. The review substantiates the conclusion that clinopyroxene can serve as an effective container for K at upper-mantle conditions.
A secondary ion mass spectrometry (SIMS) re-evaluation of B and Li isotopic compositions of Cu-bearing elbaite from three global localities
Authors: Ludwig T. , Marschall H. R. , Pogge von Strandmann P. A. E. , Shabaga B. M. , Fayek M. , Hawthorne F. C. 
Published: June 2012

AbstractCu-bearing elbaite from Paraíba (Brazil) is a highly-prized gem tourmaline. Specimens of similar quality from localities in Mozambique and Nigeria are being sold, and reliable provenance tools are required to distinguish specimens from the original locality from ‘Paraíba-type’ tourmaline from Africa. Here we present Li and B isotope analyses of Cu-bearing elbaite from all three localities and demonstrate the suitability of these isotope systems as a provenance tool. Isotopic profiles across chemically zoned grains revealed homogenous B and Li isotopic compositions, demonstrating a strong advantage of their application as a provenance tool as opposed to major, minor or trace element signatures.Li and B isotopes of all investigated samples of Cu-bearing elbaites from the three localities are within the range of previously published granitic and pegmatitic tourmaline. Anomalous isotope compositions published previously for these samples are corrected by our results.