bluuebunny/crossref_metadata_2025 huggingface dataset:
Human cardiac high‐energy phosphate metabolite concentrations by 1D‐resolved NMR spectroscopy
Authors: Bottomley Paul A. , Atalar Ergin , Weiss Robert G.
Published: March 2007

We have developed a method that can measure high‐energy phosphate metabolite concentrations in humans with 1D resolved surface‐coil NMR spectroscopy. The metabolites are measured by phosphorus (31P) NMR spectroscopy, and the tissue water proton (1H) resonance from the same volume serves as an internal concentration reference. The method requires only the additional acquisition of a 1H data set, and a simple calibration, performed separately, to determine the ratio of the signal per proton to the signal per phosphorus nucleus. The quantification method is particularly useful for human cardiac spectroscopy, where it eliminates image‐based tissue volumetry and the corrections for signal sensitivity and phase nonuniformity necessary in prior approaches. Corrections are introduced to account for blood and fat contributions to the spectra. The method was validated on phantoms of phosphate of varying concentrations and on the human calf muscle. In calf, the adenosine triphosphate (ATP) and phosphocreatine (PCr) concentrations were 5.6 ± 1.6 (mean ± SD) and 26 ± 4 mmol/kg wet wt, respectively. In normal heart, [ATP] was 5.8 ± 1.6 and [PCr] was 10 ± 2 mmol/kg wet wt. These values are in excellent agreement with prior NMR studies and biopsy data. The protocol is easily accommodated within existing 1D cardiac patient protocols, and the same approach is advantageous for eliminating tissue volumetry and sensitivity corrections when measuring concentrations by 2D and 3D resolved spectroscopy.
Single‐shot diffusion MRI of human brain on a conventional clinical instrument
Authors: Liu Guoying , Van Gelderen Peter , Duyn Jeff , Moonen Chrit T. W.
Published: March 2007

A single‐shot diffusion MRI technique on a standard clinical 1.5T scanner is presented. The method incorporates the following elements: (a) an inversion RF pulse followed by a delay of 1.3 s to null cerebral spinal fluid (CSF) signal, (b) a stimulated echo sequence (TE=56 ms, TM=100 ms) to obtain strong diffusion weighting, (c) a single‐shot gradient‐ and spin‐echo (GRASE) sequence for imaging with a modified k‐space trajectory and Carr‐Purcell Meiboom‐Gill (CPMG)‐phase cycle. The trace of the diffusion coefficient obtained with this approach is in good agreement with values reported for animal brain, and for recent human studies. It is demonstrated that single‐shot diffusion imaging of human brain is feasible on an unmodified standard instrument without high‐gradient slew rate or extreme field homogeneity.
Metabolite 1H relaxation in normal and hyponatremic brain
Authors: Rooney William D. , Ebisu Toshihiko , Mancuso Anthony , Graham Steven , Weiner Michael W. , Maudsley Andrew A.
Published: March 2007

Proton spin relaxation rate constants in normal and hyponatremic rat brain were measured to determine the sensitivity of metabolite relaxation properties to cytotoxic edema and to quantify metabolite concentration in normal and edematous brain. Relaxation rate constants for protons of water and spectral regions with dominant contributions from methyl protons of cholines (Cho), creatines (Cr), N‐acetylaspartate (NA), and lactate (Lac), and for methylene protons of glutamate (Glu) were measured at 7 T. Changes in metabolite relaxation properties associated with cytotoxic edema were a decrease in the Cr longitudinal rate constant, from 0.63 ± 0.02 s−1 (mean ± SE) in controls to 0.50 ± 0.03 s−1 in edematous brain, and an increase in the transverse rate constant of NA from 5.3 ± 0.2 s−1 in controls to 6.6 ± 0.3 s−1 in edematous brain. Four hours after induction of hyponatremia, there was a 14% reduction in summed metabolite concentrations of Cho, Cr, and NA, and a 200% increase in Lac signal intensity. It is concluded that changes in both metabolite spin relaxation and detectable spin concentration accompany the cerebral pathology of cytotoxic edema complicated with secondary ischemia.
NMR studies on water and polymer diffusion in dextran gels. Influence of potassium ions on microstructure formation and gelation mechanism
Authors: Watanabe Tokuko , Ohtsuka Akihiro , Murase Norio , Barth Peter , Gersonde Klaus
Published: March 2007

At room temperature aqueous solutions of dextrans with concentrations >25% (w/w) exhibit a sol‐gel transition in the presence of >1.0 M potassium chloride. In dextrans the gelation was unexpected due to missing anionic groups that usually provide the binding sites for cations. The quantitative investigation of the gel formation is based on changes of the diffusibility of water and dextran chains. The apparent diffusion coefficients of bulk water (in the order of 10−6 cm2/s) and of water trapped in the junction zones as well as of polymer chains (in the order of 10−7 to 10−8 cm2/s) are determined by employing pulsed field gradient stimulated echo (PFGSTE) NMR. The restricted diffusion of bulk water in viscous sols and in soft and rigid gels has been quantitatively analyzed providing data for interbarrier distances (pore size), permeabilities of the diffusion barriers (density of junction zones) and interbarrier diffusion coefficients of water. Based on already published x‐ray structure data and in accordance with the diffusion data presented in this paper “potassium‐bonding” is assumed to be the most important interaction for the formation of a microstructure and for the stabilization of crosslinks. The ionic radius of the potassium ion perfectly fits to the cage established by six oxygen atoms of glucose units of three polymer chains. Other cations, such as Li+, Na+, Rb+ and Cs+, according to their nonfitting ionic radii, do not provoke dextran gelation under these conditions. The mechanism of the transitions from sol to soft gel and further to rigid gel is discussed on the basis of restricted diffusion and x‐ray structure data.
Frequency response of multi‐phase segmented k‐space phase‐contrast
Authors: Polzin Jason A. , Frayne Richard , Grist Thomas M. , Mistretta Charles A.
Published: March 2007

A theoretical analysis of the temporal frequency response of multi‐phase segmented k‐space phase‐contrast was developed. This includes the effects of both segment duration and the number of cardiac phases that are reconstructed. An increase in the number of views per segment and the corresponding increase in segment duration results in an increased smoothing or low‐pass filtering of the time‐resolved flow waveform. Reconstruction of all intermediate cardiac phases makes the Nyquist sampling frequency independent of the number of views per segment. This analysis was verified experimentally using a multi‐phase phase‐contrast segmented k‐space MR pulse sequence. This sequence reconstructs all intermediate cardiac phases and uses fractional segments at the end of the cardiac cycle if an entire segment does not fit. The use of fractional segments increases the portion of the cardiac cycle over which data are acquired.
Detecting cortical activities from fMRI time‐course data using the music algorithm with forward and backward covariance averaging
Authors: Sekihara Kensuke , Koizumi Hideaki
Published: March 2007

A method is proposed for processing time‐course fMRI data taken wKh successlve single‐shot echo‐planar imaging. The proposed method uses a two‐dimensional version of the multiple signal classification (MUSIC) algorithm and the technique called covariance averaging, both of which were developed in the field of sensor‐array processing. The proposed method consists of four steps: calculate the averaged data covariance matrix, determine the number of activities using this covariance matrix, estimate the locations of the activities, and estimate their time evolution curves. Computer simulation resutts showed that a nearly fourfold improvement in the spatial resolution can be attained due to the method's super‐resolution capability.
Pencil excitation with interleaved fourier velocity encoding: NMR measurement of aortic distensibility
Authors: Hardy Christopher J. , Bolster Bradley D. , McVeigh Elliot R. , Iben Icko E. T. , Zerhouni Elias A.
Published: March 2007

A technique is presented for rapidly and noninvasively determining aortic distensibiltty, by NMR measurement of pulse‐wave velocrty in the aorta. A cylinder of magnetization is excited along the aorta, wtth Fourier‐veloctty encoding and readout gradients applied along the cylinder axis. Cardiac gating and data interleaving improve the effective time resolution to as high as 3 ms. Wave velocities are determined from the position of the f oot of the flow wave in the velocity profiles. Evidence of helical flow distal to the aortic arch can be seen in normal subjects, while disturbed flow patterns are visible in patients with aneurysms and dissections.
Regional myocardial oxygen tension: 19F MRI of sequestered perfluorocarbon
Authors: Shukla Himu P. , Mason Ralph P. , Bansal Navin , Antich Peter P.
Published: March 2007

A novel noninvasive method of measuring local myocardial oxygen tension (pO2) In the perfused rat heart using 19F MRI is demonstrated. Tissue pO2 was determined on the basis of the 19F spin‐lattice relaxation rate (R1) of perflubron (perfluorooctyl bromide) sequestered in the heart after IV infusion of an emulsion. Spectroscopic measurement of R1 was previously used to measure a global weighted average of oxygen status. 19F MRI now provides 3D spatial resolution indicating local cardiac pO2 under normally perfused, globally ischemic, and regionally ischemic conditions.
Simultaneous 3D NMR spectroscopy of fluorine and phosphorus in human liver during 5‐fluorouracil chemotherapy
Authors: Li Chun‐Wei , Gonen Oded
Published: March 2007

Simultaneous multivoxel 31P and 19F 3D localized NMR spec‐troscopy is demonstrated on a phantom and in the liver of patients undergoing bolus‐infusion 5‐fluorouracil chemotherapy. The 19F and 31P spectra were localized with 8 × 8 × 8 3D chemical‐shift imaging, with both nuclei sharing the same field of view and voxel size (27 and 64 ml in phantom and liver, respectively) using a 1.5‐Tesla clinical imager with two RF channels and a dual‐tuned surface coil. The repetition time (TR = 0.26 s) and Ernst nutation angles (θE = 32° for 19F, 28° for 31P) were chosen to optimize the signal‐to‐noise ratio (SNR) per‐untt time for the 0.5‐ to 2‐s T1 range of the 19F and 31P metabolites of interest The overall examination time, including tuning, imaging, shimming and dual‐nuclear spectroscopy, was under 90 min. Simultaneous acquisition of 31P and 19F spectra will permit the study of the influence of hepatic and/or tumor metabolism on the uptake and catabolism of fluoropyrimidine drugs with no extra measurement time.
Improving the temporal resolution of functional MR imaging using keyhole techniques
Authors: Gao Jia‐Hong , Xiong Jinhu , Lai Song , Haacke E. Mark , Woldorff Marty G. , Li Jinqi , Fox Peter T.
Published: March 2007

Using a keyhole technique, it is shown that the data acquisition rate of gradient‐echo imaging for functional MRI (fMRI) studies can be increased substantially. The resulting enhancement of the temporal resolution of fMRIs was accomplished without modifying the hardware of a conventional MRI system. High spatial resolution fMRI images were first collected with conventional full k‐space acquisition and image reconstruction. Using the same data set, simulation reconstruction using the keyhole principle and zero‐padding were performed for comparison with the full k‐space reconstruction. No significant changes were found for fMRI images generated from the keyhole technique with a data sharing profile of 50% of the k‐space. As k‐space data sharing profiles increased to 75 and 87.5%, the keyhole fMRI images began to show only modest changes in activation intensity and area compared with the standard images. In contrast, zero‐padding fMRI images produced a significant disparity both in activation intensity and area relative to the truly high‐resolution fMRI images. The keyhole technique's ability to retain the intensity and area of fMRI information, while substantially reducing acquisition time, makes it a promising method for fMRI studies.
Optimization of torque‐balanced asymmetric head gradient coils
Authors: Alsop David C. , Connick Thomas J.
Published: March 2007

Local gradient coils can improve the performance of echo‐planar, diffusion, and short TE imaging in the brain. A modified singular value decomposition algorithm, which allows the rapid optimization and comparison of designs, was employed to optimize head size gradient coils. A theoretical expression for the torque on a cylindrical coil is presented and used to design coils that are free from torque while pulsed within a magnetic field. Gradient coils of various lengths both with and without torque constraints were compared; although torque‐free coils do not perform as well as unbalanced coils, asymmetric torque‐balanced coils can achieve comparable homogeneity with only a modest Increase in inductance and resistance. Both types of coils outperform body size gradient coils by a dramatic margin. A three‐axis head gradient designed using these techniques was constructed and used for brain imaging on a clinical scanner.
Fast interleaved echo‐planar imaging with navigator: High resolution anatomic and functional images at 4 tesla
Authors: Kim Seong‐Gi , Hu Xiaoping , Adriany Gregor , Uǧurbil Kâmil
Published: March 2007

Echo‐planar Imaging (EPI) Is sensitive to magnetic field inhomogeneities, which lead to signal loss and geometric distortions of the image. Magnetic field inhomogeneities induced by susceptibility differences, as encountered in the human body, increase with the magnetic field strength, thus, complicating implementation of high resolution EPI techniques on high magnetic field systems. These problems were overcome by using a fast multishot high resolution EPI method that uses variable flip angles, center‐out k‐space sampling, and navigator echoes. This approach maximizes signal‐to‐noise ratio, reduces flow artifacts, and permits correction of intersegment amplitude and phase variations, providing high spatial and temporal resolution. This scheme can be implemented with a single magnetization preparation for contrast that precedes the segments. The utility of this ultrafast segmented EPI technique with navigator is demonstrated for anatomic and functional imaging studies on the human brain at 4 T.
Fast 3D large‐angle spin‐echo imaging (3D FLASE)
Authors: Ma Jingfei , Wehrli Felix W. , Song Hee Kwon
Published: March 2007

A rapid steady‐state 3D spin‐echo imaging pulse sequence, based on the principle of nutating the spins by an angle greater than 90°, has been designed and implemented on a clinical 1.5‐T whole‐body MR scanner. The pulse sequence, denoted fast large‐angle spin‐echo (FLASE), has been optimized for high‐resolution imaging of tissues with short T2 and T2*. Features of FLASE include a minimum‐phase Shinnar‐Le Roux excitation pulse and distribution of phase‐ and slice‐encoding gradients before and after the 180° refocusing pulse to minimize the critical time delay between inversion and restoration of the residual longitudinal magnetization and for minimizing echo time. A Bloch equation analysis, corroborated by experimental data, shows FLASE signal‐to‐noise to be superior to its closest analog, 3D rapid spin‐echo excitation (RASEE) (Jara et al., Magn Reson Medicine 29, 528 (1993)), and 3D gradient‐recalled acquisition in steady state (GRASS). It is demonstrated that with judicious RF phase‐cycling and steady state operation, FLASE can produce high‐quality microimages free of intravoxel phase dispersion from susceptibility‐induced background gradients. The performance of the method is exemplified with ultra high‐resolution images of trabecular bone in vitro and in vivo In the human calcaneus and wrist at voxel sizes as low as 98 × 98 × 200 μm3. Finally, the contrast behavior of refocused FLASE can be altered by disrupting the steady state analogous to gradient echo imaging.
A Modified sub‐second fast‐STEAM sequence incorporating bipolar gradients for in vivo diffusion imaging
Authors: Yongbi Martin N. , Ding Shujun , Dunn Jeffrey F.
Published: March 2007

A modified high‐speed stimulated‐echo acquisition mode (STEAM) diffusion sequence (90°‐TE/2−90°‐TM‐[α‐TE/2‐STE]n) incorporating bipolar diffusion gradients that are less sensitive to macroscopic motion‐induced artifacts is presented. Diffusion encoding was performed only during the first echo interval (TE1) with bipolar gradients that were implemented on all three mutually orthogonal axes. Calibration measurements on phantoms filled with water, isopropanol, and dimethyl sulfoxide yielded apparent diffusion coefficients (ADC) consistent with published values. Non‐ECG‐triggered in vivo images acquired on rat brain with relatively high b values (˜450 s/mm2) indicated minimal motion artifacts. Evaluated ADCs averaged over the cortex, left mid‐brain, right mid‐brain, regions yielded (0.91 ± 0.02), (1.06 ± 0.02), (1.01 ± 0.03) × 10−3 mm2s−1, respectively.
Myocardial signal response to dipyridamole and dobutamine: Demonstration of the BOLD effect using a double‐echo gradient‐echo sequence
Authors: Li Debiao , Dhawale Paritosh , Rubin Patricia J. , Haacke E. Mark , Gropler Robert J.
Published: March 2007

The purpose of this study was to examine the differential myocardial signal responses due to the blood oxygen level dependent (BOLD) effect in magnetic resonance imaging (MRI) under differing conditions of myocardial oxygen supply and demand. The signal response was measured when myocardial blood flow was increased in excess of oxygen demand or when flow was increased in response to increased myocardial oxygen demand. Normal volunteers were studied using a segmented, interleaved, double‐echo, gradient‐echo sequence at baseline conditions and during pharmacological stress with either dipyridamole (n = 5) or dobutamine (n = 6). Changes in T2* in the myocardium during stress were calculated. Peak coronary flow velocity was measured at rest and during stress using a breath‐hold phase contrast technique. Administration of dipyridamole induced a 124 ± 27% increase in coronary blood flow which resulted in a 46 ± 22% increase in T2*, consistent with a decrease in myocardial venous deoxyhemoglobin concentration as myocardial oxygen supply exceeds demand. In contrast, the administration of dobutamine resulted in a 41 ± 25% increase in coronary blood flow but no significant change in T2* (−5 ± 19%), consistent with a lack of change in myocardial venous deoxyhemoglobin concentration and balanced oxygen supply and demand. Thus, alterations in the relationship between myocardial oxygen supply and demand appear to be detectable using BOLD MRI.
Observation and quantitation of lactate in oxidative and glycolytic fibers of skeletal muscles
Authors: Shen Dee , Gregory Carl D. , Dawson M. Joan
Published: March 2007

In 1H NMR spectroscopic studies of fatiguing skeletal muscles, two peaks consistently arise near 1.3 ppm, typically 15–20 Hz apart at 300 MHz. From a variety of NMR and biochemical evidence, both peaks are identified as lactate. Both the CH3 and CH protons of lactate experience the same shift in intact muscle; this rules out chemical bonding or complexation. The ratio of intensity of the two methyl peaks varies with muscle type and suggests a correlation with oxidative and glycolytic fiber populations. The shift can be accounted for by the presence of paramagnetic myoglobin in the oxidative fibers. Phantom studies, as well as oxygen, temperature, field, and orientation dependence of the muscle spectra are all consistent with an explanation based upon bulk magnetic susceptibility. It is concluded that the two lactate peaks represent separate contributions from glycolytic and oxidative muscle fibers.
13C‐NMR relaxation in glycogen
Authors: Overloop Kristen , Vanstapel Florent , Van Hecke Paul
Published: March 2007

This study is the first report on the multiexponential T2 relaxation of the 13C‐1 carbon of glycogen. In contrast to T1 relaxation, which does not display observable multiexponential decay behavior, T2 relaxation is described by a continuous distribution of T2 times. Changes in molecular weight and sample viscosity, which affect the overall mobility of the glycogen particle have little influence on T1 and T2 relaxation times. This is in contradiction with earlier results that T2 is dominated by the overall motion of the glycogen particles [L.‐H. Zang Biochemistry 29, 6815–6820 (1990)]. T1 depends strongly on the external field Bo and is almost temperature independent in the range 23–37°C whereas T2 is field independent and varies appreciably with temperature. The experimental T1 and T2 relaxation data are shown to be consistent with existing theoretical models for relaxation, suitably modified to include a distribution of correlation times for the internal motions. The presence of fast decaying components (short T2) in the FID implies broad line components in the frequency spectrum and the corresponding need to appropriately set the integration limits for the quantification of the glycogen peak.
Optimizing MRI signal‐to‐noise ratio for quadrature unmatched RF coils: Two preamplifiers are better than one
Authors: Sorgenfrei Birgit L. , Edelstein William A.
Published: March 2007

Using separate preamplifiers for the two outputs of a quadrature receive coil (and then combining the preamplifier outputs in a quadrature hybrid) provides a better signal‐to‐noise ratio (SNR) than is obtained by directly combining the quadrature outputs in a hybrid followed by a single preamplifier. The advantage of the two‐preamplifier configuration increases when the body coil impedance changes and is no longer matched to 50 ohms. Using 0.4 dB noise figure preamplifiers, theory predicts 1.53, 0.42, 0, 0.42, and 1.53 dB SNR advantage of the two‐preamplifier configuration over the one‐preamplifier arrangement at body coil impedances of 12.5, 25, 50, 100, and 200 ohms, respectively. Experimental hot/cold resistor noise figure measurements indicate 2.86, 0.65, 0.36, 0.83, and 1.40 dB noise figure advantage for the two preamplifier configuration relative to the one‐preamplifier configuration at those impedances. Empirical gains larger than theoretically calculated are attributable to insertion losses of various circuit elements, such as the quadrature hybrid, for the onepreamplifier configuration.
Estimation of in vivo proton intrinsic and cross‐relaxation rates in human brain
Authors: Chai Jyh‐Wen , Chen Clayton , Chen Joen Hor , Lee San‐Kan , Yeung Hong N.
Published: March 2007

By using on‐resonance binomial pulse saturation of the immobile component in tissues and by monitoring the time development of the longitudinal decay of the free water magnetization, it has been shown that it is possible to estimate physical model parameters not directly measurable by conventional methods. Since pulsed saturation is easy and safe to implement in a clinical MRI machine, it should be possible to estimate these parameters in vivo by the same means. In this article, we report the results of such estimates of the parameters of the principal components (gray and white matter) in brains of two normal volunteers.
Effects of blood flow modifiers on tumor metabolism observedin vivoby proton magnetic resonance spectroscopic imaging
Authors: Bhujwalla Zaver M. , Shungu Dikoma C. , Glickson Jerry D.
Published: March 2007

Perfusion plays a key role in tumor proliferation and therapeutic response. Tumor heterogeneity necessitates use of the highest spatial resolution to monitor metabolic correlates of blood flow changes. This is best achieved with1H NMR spectroscopy, which permits noninvasive acquisition of high resolution spectroscopic images (SI) of subcutaneous tumors in a relatively short scan time (e.g., 12‐25 μl voxels with signal‐to‐noise ratio 7:1 in 30 min at 4.7 T). This study seeks to identify1H spectroscopic indices of tumor blood flow. Proton SI of subcutaneous murine RIF‐1 tumors were recorded (a) before and after administration of nicotinamide (1 g/kg) toincreaseblood flow, and (b) before and after hydralazine (10 mg/kg) todecreaseflow. Nicotinamide produced a significant decrease in the total choline peak amplitudes, which subsequent high resolution NMR spectroscopy of tumor extracts revealed to be due to decreases in phosphocholine and glycerophosphocholine. The deamidation of nicotinamide to nicotinic acid, which is known to have hypolipidemic effects and to stimulate the formation of prostaglandins, may have sufficiently altered lipid metabolism to affect thein vivoconcentration of the NMR‐visible choline‐containing compounds. The main effect of hydralazine was a significant increase of lactate, which is consistent with a reduction of tumor blood flow.
Post‐acquisition correction of MR inhomogeneities
Authors: Lee Scott K. , Vannier Michael W.
Published: March 2007

Signal inhomogeneities in volumetric head MR scans are a major obstacle to segmentation and neuromorphometry. The fuzzy c‐means (FCM) statistical clustering algorithm was extended to estimate and retrospectively correct a multiplicative inhomogeneity field in T1‐weighted head MR scans. The method was tested on a mathematically simulated object and on seven whole head 3D MR scans. Once initial parameters governing operation of the algorithm were chosen for this class of images, results were obtained without intervention for individual MR studies. Post‐acquisition inhomogeneity correction by extended FCM clustering improved overall image uniformity and separability of gray and white matter intensities.
A Framework for Theory and Research on Adult Education Participation
Authors: Cookson Peter S.
Published: March 2007

Proposed is a comprehensive, multivariate, multi-realm theoretical framework with which to integrate and advance the theory and research on adult education participation (AEP). The elements of the ISSTAL model, as elaborated by D. H. Smith, are identified, defined, and exemplified in terms of the current literature on AEP. This article describes elements of the framework which have already been investigated and those for which there are gaps in the literature. Suggestions for further research to close those gaps are given. The framework has significance for theory and research on AEP as Well as more general theory-building efforts in adult education.
The Airway Tide in Transportation
Authors: Rentzel Delos W.
Published: March 2007

A break-through in air freight is here through use of more efficient cargo planes which will bring air costs near surface-carrier costs by 1965 and directly competitive by 1970. By that time, air cargo will swell to 4.5 billion ton-miles, a sevenfold increase over 1960 figures. Our increasing gross national product guarantees continuing demand for air cargo. Possibility of air carriage of all surface mail at costs competitive with surface costs is part of air cargo's bright future. Emerging nations, with planes as tools, can move directly onto the world's commercial pathways. Planes will continue to increase in value as economic and sociological tools in the world political struggle. The United States should preferably develop better short-haul passenger and freight planes; better cargo-handling containers and packaging; and a combination passenger-cargo plane rather than the costly Mach 3 transport, a "prestige" item due to cost the taxpayer as much as $600 million. Surface passenger and freight media face troubles and rising costs, whereas air-cargo firms envision lowering costs with better planes.
Manpower—A Prime Resource
Authors: Williams Ernest W.
Published: March 2007

Labor is the largest single cost element in all forms of transport. The skilled work force is also a major asset which makes possible the conduct of a vital and complicated business. Growth of competition among transport technologies, the growth of private and unregulated transport, and the uneven impact of public policy have put regulated carriers of all types under severe pressure. With freight rates controlled by competition and with wage rates and prices rising, extreme pressure to economize on labor and to devote available funds to cost-reducing developments has persisted for many years. Carrier types, especially the railroads, which have felt the combined impact of adverse government policy and the sharpening of competition have reduced their work forces drastically. Peculiarly difficult problems face them and their workers. To the extent that some types of transport have been overstimulated by public policy while others have been held back, similar maladjustments in the size of the labor force committed to each have been brought about. Movement toward a more rational system will require painful adjustment which should not be ignored in adjusting governmental policy.
China after Nixon
Authors: Mirsky Jonathan
Published: March 2007

China's development since the Cultural Revolution is proceeding in unusual directions. Lack of success in some areas and questionable goals in others do not detract from the innovative and creative aspects of the experiment which is based on the elimination of competition and the encouragement of mutual aid.
Education and Equality
Authors: Staaf Robert J. , Tullock Gordon
Published: March 2007

It is fairly clear that higher education, among other things, works a considerable income redistribution. In general, this redistribution is from the poor to those people who would be very well off even without education. The higher educational system increases the degree of income differentia tion in the society. People who have considerable natural talent, who would therefore have high incomes in any event, are given higher incomes at the expense of the taxpayer. There is a secondary aspect of income redistribution related to the higher educational system. It has been argued that the children of upper class parents gain more than the children of poor parents and that this difference is greater than the difference between the taxes paid to support education by these two groups. It is not certain that this is so; in any event, the question of the wealth of the parents of the students who receive the taxpayer's gift seems less important than the actual potential lifetime earnings of the recipients. Of course, it is possible to offset the regressive nature of the higher edu cational system by progressive measures in other parts of gov ernment; however, it would seem simpler to convert the higher educational system to one which provides less in the way of benefits for the rich at the expense of the poor.
Getting and Spending
Authors: Danziger Sheldon H. , Lampman Robert J.
Published: March 2007

The selected time series on income and consumption appear to give a clear picture of postwar change along the following lines: family incomes have grown substantially ; consumption patterns have shifted away from necessities; income inequality has not increased; and poverty and intergroup income differences have declined. However, the broad indicators on which these conclusions are based do not illuminate the processes by which income is generated, consumption is shared, and costs are borne. The authors raise a set of questions related to the measurement and interpretation of the indicators. The answers to these questions suggest that a time series does not speak for itself and that a careful analysis of postwar changes awaits specification of the socioeconomic processes that generate the indicators.
Race and Residence: The Shifting Basis of American Race Relations
Authors: Roof Wade Clark
Published: March 2007

Racially-segregated ghettos evolved in the early decades of this century, first in northern cities and later throughout the nation. Levels of urban residential segregation for blacks have remained high over the years and—unlike the earlier pattern for European immigrants—have not declined as blacks have made economic progress. Despite modest declines in segregation in the sixties, metropolitan decline in the seventies and structural shifts in employment conditions for blacks have resulted in growing concern for problems of de facto segregation. Mounting attention to housing discrimination and the residential basis of current black-white tensions are discussed.
Achieving a just Legal System: The Role of State Intermediate Appellate Courts
Authors: SPAETH EDMUND B.
Published: March 2007

State intermediate appellate courts are a most important part of our legal system. They enable the state's highest court to concentrate on a few cases; they guide the trial courts; and they often point the way to needed changes in the law. But they are overworked, with resulting delays and dissatisfaction. To improve their performance, and to increase their usefulness to the highest court and the trial courts, the following should be done: their decisions should be made final, subject to review only in the discretion of the state's highest court; they should not be divided into regional divisions or into specialized courts; they should in every case file a written opinion; their judges should be nominated on merit and confirmed by the legislature; and their staffs should be reorganized. Given modern caseloads, this would involve delegating some judicial responsibility to staff. But on balance, the gain would be greater than the loss, for the judges would be enabled to spend more of their time deciding cases.
A Five-Year Housing Forecast
Authors: SUMICHRAST MICHAEL
Published: March 2007

Even to attempt to make a long-term forecast seems like a useless and idiotic exercise. In the climate we live in today, we are not smart enough to see beyond a couple of days, or at most, a few weeks. Still, it has to be done, not just to fill the pages of magazines, but for planning purposes. So we look at possible scenarios under various assumptions. Housing, as we all know, is highly credit sensitive. Thus our assumptions are heavily weighted toward future developments in the financial markets. What we are actually saying is that if interest rates decline, more people will be willing—and able—to buy homes. If interest rates do not decline, people will not buy. There are three ways of looking at things: the optimistic, the pessimistic, and the most likely forecasts. All three will be mentioned in this article.
Quality, Cost, and Clinical Decisions
Authors: DONABEDIAN AVEDIS
Published: March 2007

Clinical decisions require determining the objectives of care as well as selecting and implementing a strategy of care. At the very least the optimal strategy balances the expected benefit and harm from technical interventions. Health care practitioners tend to specify optimal strategies based on what they consider to be best for patients, without regard to monetary cost. This is an absolutist definition of quality. Individuals may place different valuations on the outcomes, are concerned with the monetary costs to themselves, and are particularly sensitive to the attributes of the interpersonal relationship with the practitioners. Including all of these leads to an individualized definition of the quality of care. But this specification of quality may be in conflict with a social definition of quality, which takes into account social as well as individual monetary costs, externalities, and the social distribution of quality. The health care professions may respond to the conflict in several ways, which are described in this article as evasion, rejection and confrontation, anticipation, advocacy, active complicity, passive complicity, and ambiguous adaptations.
The Position of the USSR on Nuclear Weapons and Arms Control
Authors: KOCHETKOV YEVGENIY N.
Published: March 2007

The Soviet nuclear doctrine is to prevent nuclear war. Nuclear power in the hands of the USSR is a means of defense against nuclear attack. The Soviet Union has officially renounced first use of nuclear weapons and expects other nuclear nations to follow suit. Progress in the negotiations on strategic and European nuclear weapons can be achieved only on the basis of the principles of equality and equal security. The Soviet Union will do everything to keep the present strategic parity with the United States and will not allow the United States to gain nuclear superiority. Among the most urgent tasks of today is to prevent an extension of the arms race into outer space. Given goodwill, common sense, and the right principles, the USSR and the United States can cooperate successfully in the area of arms control and disarmament.
Presidential Decision Making and Opinion Polls
Authors: BEAL RICHARD S. , HINCKLEY RONALD H.
Published: March 2007

During the first 29 months of the Reagan administration the president's long-time pollster, Richard Wirthlin, met with Ronald Reagan more than 25 times to discuss politics and polls, and he delivered memoranda on the results of over 40 public opinion studies to the president's top three aides: Jim Baker, Mike Deaver, and Ed Meese. This is indicative of the ascendancy during the era of the modern presidency of opinion polls in the process that presidents must follow to establish a public agenda and build coalitions to secure support. A number of methodological, technological, political, and management factors have contributed to the rise of opinion polls in presidential decision making, to the point that they are omnipresent in this process. Decisions relating to federalism, the gender gap, fairness, unemployment, and deployment of intermediate nuclear forces in Western Europe have been affected by polls from various sources. The evidence generated indicates that opinion polls are probably more important after a presidential election than before it.
Economic Restructuring: The British Experience
Authors: ROSE DAVID , VOGLER CAROLYN , MARSHALL GORDON , NEWBY HOWARD
Published: March 2007

This article deals with certain aspects of British economic decline. After a short historical review of British economic performance, the phenomenon of deindustrialization is examined. Two major economic theories of deindustrialization are discussed alongside empirical evidence of the recent, rapid decline in Britain's manufacturing base and its worsening trade performance in goods and services. The effects of multinational corporations are also briefly examined. In the final section of the article, attention is given to some of the social and political aspects of deindustrialization. In particular, evidence on poverty, unemployment, and living standards in contemporary Britain is discussed in relation to a sociological model that attempts to explain certain apparent paradoxes of British society. This model is an extension of T. H. Marshall's pioneering work on citizenship and social class and serves to highlight both the continuing stabilizing effects of the modern status order and the possibility of further clashes between the competing claims of citizenship and social class.
Employee Benefits and Social Welfare: Complement and Conflict
Authors: ROOT LAWRENCE S.
Published: March 2007

Employee benefits constitute a major vehicle for the provision of income security for Americans. Since the 1940s, wage supplements, particularly in the form of pensions and health insurance, have expanded to provide protections that are the province of public programs in most other Western countries. Building upon the precedents of the welfare capitalism of the early 1900s, the growth of employee benefits has been actively stimulated by federal tax and regulatory policies. The emergence of employee benefits as a major source of income security and health insurance has reduced the aggregate need for public programs, but it has left those in lower-paying, less stable jobs—disproportionately women and minorities—both unprotected and with fewer political allies to press for improved protections. The implementation of the employee benefit programs has also created financial interests in the existing structure that would resist changes that would diminish their role.
The Politics of Religion in Revolutionary Nicaragua
Authors: DODSON MICHAEL
Published: March 2007

The Popular Insurrection in Nicaragua is examined against the backdrop of the grass-roots mobilization and protest that built up between 1968 and 1978. Particular attention is given to the linkages between grass-roots religious change and political mobilization. It is argued that the democratization of religious experience in the decade following the 1968 meeting of the Conference of Latin American Bishops in Medellín greatly facilitated the participation of the poor in the Nicaraguan Revolution, but that it also sowed the seeds of intrachurch conflict after the Triumph of the Revolution. Post-Triumph conflict between church and state and between the church hierarchy and the so-called popular church are then examined, with a view to showing that the major religious issue in revolutionary Nicaragua is not Marxism versus the church, but democratization in the church and in the political order.
Eastern and Southern European Immigrants: Expectations, Reality, and a New Agenda
Authors: KROMKOWSKI JOHN A.
Published: March 2007

Throughout the history of their settlement in America, Eastern and Southern European ancestry groups have varied dramatically. Yet there is a logic to combining all these groups into a single analytical category, based on the time of their arrival, their religious and cultural differences from other Americans, and their living memories of gaining freedom from serfdom and peonage. From 1924 to 1964, a national immigration policy of selection and restriction effectively excluded immigrants from these regions of Europe using flawed social scientific rationales that tagged Eastern and Southern Europeans as undesirable and inferior. By 1965, however, a fresh spirit of tolerance and consensus had come to prevail. The 1980 census data on ancestry populations and foreign-born persons from Eastern and Southern Europe sustain the notion that local variations should not be ignored. Finding the convergent issues of various ethnic populations remains on the American agenda of liberty and justice for all. Ancestry groups with recollections of the immigrant experience could become a pivotal force in resolving conflict during the next era of immigration.
Human Renewal in the Revitalization of the Industrial City
Authors: MANGUM GARTH , MANGUM STEPHEN
Published: March 2007

Forces following World War II caused a flow of industrial jobs to the suburbs, trapping a central-city minority population unable to compete for the office jobs remaining. Service jobs primarily for the women and a welfare system unwilling to support male-headed families contributed to family breakup. A variety of programs were introduced in response, but the better they worked the worse conditions became because the successful joined the flow to the suburbs. The result is a dual economy with a modern sector staffed by commuting expatriates overlaid on a native population basically unconnected to the city's economy. Since there are already more jobs than residents in the central city, economic development is largely irrelevant to them. The challenge is to bring the residents into the heart of the city's economy, yet create an environment that will encourage the successful to stay.
Nigeria Restrained: Foreign Policy under Changing Political and Petroleum Regimes
Authors: SHAW TIMOTHY M.
Published: March 2007

The cyclical pattern of Nigeria's external relations has followed that of its political constitution and petroleum production. Aspirations to great-power status in the 1970s have yielded to austerity and modesty in the 1980s. Yet core concerns about development, integration, and liberation continue despite a series of changes in governmental structure and oil profitability. Throughout, there have been lively debates about preferred policy directions and alternative analytic explanations, symptomatic of the openness of Nigeria's political culture. If its political economy can become more self-reliant and self-sustaining, then its foreign policy can yet be influential. But leadership in Africa requires the redefinition of established linkages with other, mainly Western, economic partners. If Nigeria can use the present period of economic difficulty to reduce its oil dependence, then its ambitions in and for Africa may yet be realized in the coming decade.
A Symposium: What Future Directions for Academic Exchange?
Authors: SEABURY PAUL , PYE A. KENNETH , BLITZ MARK , BILLINGTON JAMES H.
Published: March 2007

Forty years leaves nothing unchanged, and certainly not the Fulbright program. How have its objectives changed, how should they change? Four informed observers and former or present participants in Fulbright and other exchange programs here present their views. Paul Seabury argues for a more sharply focused Fulbright program in an age when it is only a drop in a sea of exchanges, and urges that that focus should serve national interests. James H. Billington suggests that Fulbright or part of it be upgraded to focus on “brighter students or future leaders.” Mark Blitz points out that the strong support the program now receives from the administration and in Congress is based not so much on the desire to “enhance academic opportunities or...`mutual understanding' ” but rather on the hope of improving prospects for democratic development, a central purpose of our foreign policy. A. Kenneth Pye emphasizes the traditional objective of mutual understanding, and the importance of avoiding politicization and respecting the independent role of the binational commissions; he presents a variety of proposals for improvement in the program.
The Retreat of Folly: Some Modest Replications of Inner-City Success
Authors: CURTIS LYNN A.
Published: March 2007

Community-based alternatives to the criminal justice system, like block watches and patrols, that seek to reduce opportunities for crime without addressing the causes of crime have, in part, become public relations gimmicks designed, at best, to assuage fear. Inner-city residents want more crime prevention along the lines of Argus, Centro, the Community Boards, and Umoja. Preliminary evaluation results from a national demonstration in inner-city neighborhoods show considerable success with bubble-up grass-roots initiatives that both address the causes of crime and reduce the opportunities for it. The demonstration suggests that inner-city community organizations can be more cost-effective than police in leading such initiatives. With technical assistance, the community groups, located in some of the nations' most devastated inner-city ghettoslums, were able to assemble the resources to continue on after their initial 30-month grants ran out. The total funding raised for such financial self-sufficiency exceeded the initial grants. The future lies in more ambitious replications of the principles underlying Argus, Centro, the Community Boards, and Umoja.
The Portland Formula: Family, Business, and Community
Authors: CLARK J. E.
Published: March 2007

The city of Portland recognizes that past solutions to reducing crime and violence have not worked. The innovations of the Clark administration are based on family, business, and community. Service centers provide family-like supports for high-risk youth and coordinate closely with job training and placement through one regional private industry council. The Portland police are becoming more citizen based. Top-down planning for youth employment through a leaders' round table, called Portland Investment, is being complemented with bubble-up thinking to start youth enterprises at the block level.
The President and Congress in the Media
Authors: LARSON STEPHANIE GRECO
Published: March 2007

The nature and determinants of presidential and congressional media coverage are described in this article, and the untested assumptions concerning political consequences of coverage are discussed. The argument that media coverage inherently enhances power, so that the president's influence is unconditionally increased at the expense of Congress's, is challenged through logic and example. The need to investigate the dynamics of media impact beyond public opinion, the nature of institutional coverage in various political settings, and the promise of congressional hearings for counterbalancing presidential coverage are discussed.