Showing papers by "University of Connecticut published in 1990"

The American College of Rheumatology 1990 Criteria for the Classification of Fibromyalgia. Report of the Multicenter Criteria Committee.

Abstract: To develop criteria for the classification of fibromyalgia, we studied 558 consecutive patients: 293 patients with fibromyalgia and 265 control patients. Interviews and examinations were performed by trained, blinded assessors. Control patients for the group with primary fibromyalgia were matched for age and sex, and limited to patients with disorders that could be confused with primary fibromyalgia. Control patients for the group with secondary-concomitant fibromyalgia were matched for age, sex, and concomitant rheumatic disorders. Widespread pain (axial plus upper and lower segment plus left- and right-sided pain) was found in 97.6% of all patients with fibromyalgia and in 69.1% of all control patients. The combination of widespread pain and mild or greater tenderness in greater than or equal to 11 of 18 tender point sites yielded a sensitivity of 88.4% and a specificity of 81.1%. Primary fibromyalgia patients and secondary-concomitant fibromyalgia patients did not differ statistically in any major study variable, and the criteria performed equally well in patients with and those without concomitant rheumatic conditions. The newly proposed criteria for the classification of fibromyalgia are 1) widespread pain in combination with 2) tenderness at 11 or more of the 18 specific tender point sites. No exclusions are made for the presence of concomitant radiographic or laboratory abnormalities. At the diagnostic or classification level, the distinction between primary fibromyalgia and secondary-concomitant fibromyalgia (as defined in the text) is abandoned.

Sampling-Based Approaches to Calculating Marginal Densities

Abstract: Stochastic substitution, the Gibbs sampler, and the sampling-importance-resampling algorithm can be viewed as three alternative sampling- (or Monte Carlo-) based approaches to the calculation of numerical estimates of marginal probability distributions. The three approaches will be reviewed, compared, and contrasted in relation to various joint probability structures frequently encountered in applications. In particular, the relevance of the approaches to calculating Bayesian posterior densities for a variety of structured models will be discussed and illustrated.

Sampling-based approaches to calculating marginal densities

Abstract: Stochastic substitution, the Gibbs sampler, and the sampling-importance-resampling algorithm can be viewed as three alternative sampling- (or Monte Carlo-) based approaches to the calculation of numerical estimates of marginal probability distributions. The three approaches will be reviewed, compared, and contrasted in relation to various joint probability structures frequently encountered in applications. In particular, the relevance of the approaches to calculating Bayesian posterior densities for a variety of structured models will be discussed and illustrated.

Illustration of Bayesian Inference in Normal Data Models Using Gibbs Sampling

Abstract: The use of the Gibbs sampler as a method for calculating Bayesian marginal posterior and predictive densities is reviewed and illustrated with a range of normal data models, including variance components, unordered and ordered means, hierarchical growth curves, and missing data in a crossover trial. In all cases the approach is straightforward to specify distributionally and to implement computationally, with output readily adapted for required inference summaries.

The biochemical basis for discoloration in fresh meat: a review

Abstract: The color of fresh meat is an extremely important characteristic influencing the consumer's purchase decision. The stability of pigments in meat is highly variable and is governed by a variety of factors. The effects of exogenous factors (i.e., storage and display conditions) have been well researched. The control of these variables currently offers the best means for maximizing meat color stability. Biochemical factors which are inherent to the meat itself have received far less research attention and an understanding of these presents the greatest potential for prolonging color stability in fresh meat.

Phase transitions and critical fluctuations in the visual coordination of rhythmic movements between people.

Abstract: By watching each other's lower oscillating leg, 2 seated Ss kept a common tempo and a particular phase relation of either 0 degrees (symmetric mode) or 180 degrees (alternate mode). This study investigated the differential stability of the 2 phase modes. In Experiment 1, in which Ss were instructed to remain in the initial phase mode, the alternate phase mode was found to be less stable as the frequency of oscillation increased. In addition, analysis of the nonsteady state cycles revealed evidence of a switching to the symmetric phase mode for the initial alternate phase mode trials. In Experiments 2 and 3, Ss were instructed to remain at a noninitial phase angle if it was found to be more comfortable. The transition observed between the 2 phase modes satisfies the criteria of a physical bifurcation--hysteresis, critical fluctuations, and divergence--and is consonant with previous findings on transitions in limb coordination within a person.

Principles of igneous and metamorphic petrology

Abstract: This textbook provides a basic understanding of the formative processes of igneous and metamorphic rock through quantitative applications of simple physical and chemical principles. The book encourages a deeper comprehension of the subject by explaining the petrologic principles rather than simply presenting the student with petrologic facts and terminology. Assuming knowledge of only introductory college-level courses in physics, chemistry, and calculus, it lucidly outlines mathematical derivations fully and at an elementary level, and is ideal for intermediate and advanced courses in igneous and metamorphic petrology. The end-of-chapter quantitative problem sets facilitate student learning by working through simple applications. They also introduce several widely-used thermodynamic software programs for calculating igneous and metamorphic phase equilibria and image analysis software. With over 350 illustrations, this revised edition contains valuable new material on the structure of the Earth's mantle and core, the properties and behaviour of magmas, recent results from satellite imaging, and more.

Cardiomyopathy of overload. A major determinant of prognosis in congestive heart failure.

Abstract: MORE than 80 years ago, Sir James MacKenzie1 noted: "The more I study the symptoms of heart failure, and the more I reflect on the part played by the heart muscle, the more convinced I am that... heart failure is due to the exhaustion of the reserve force of the heart muscle." Except for the cardiac glycosides, however, therapy for congestive heart failure generally has focused on the systemic signs and symptoms that appear when the failing heart becomes unable to meet the hemodynamic demands of the body, rather than on abnormalities in the heart muscle itself, which both cause . . .

Hierarchical Bayesian Analysis of Changepoint Problems

Abstract: SUMMARY A general approach to hierarchical Bayes changepoint models is presented. In particular, desired marginal posterior densities are obtained utilizing the Gibbs sampler, an iterative Monte Carlo method. This approach avoids sophisticated analytic and numerical high dimensional integration procedures. We include an application to changing regressions, changing Poisson processes and changing Markov chains. Within these contexts we handle several previously inaccessible problems.

Evidence for horizontal transmission of the P transposable element between Drosophila species.

Abstract: Several studies have suggested that P elements have rapidly spread through natural populations of Drosophila melanogaster within the last four decades. This observation, together with the observation that P elements are absent in the other species of the melanogaster subgroup, has lead to the suggestion that P elements may have entered the D. melanogaster genome by horizontal transmission from some more distantly related species. In an effort to identify the potential donor in the horizontal transfer event, we have undertaken an extensive survey of the genus Drosophila using Southern blot analysis. The results showed that P-homologous sequences are essentially confined to the subgenus Sophophora. The strongest P hybridization occurs in species from the closely related willistoni group. A wild-derived strain of D. willistoni was subsequently selected for a more comprehensive molecular examination. As part of the analysis, a complete P element was cloned and sequenced from this line. Its nucleotide sequence was found to be identical to the D. melanogaster canonical P, with the exception of a single base substitution at position 32. When the cloned element was injected into D. melanogaster embryos, it was able to both promote transposition of a coinjected marked transposon and induce singed-weak mutability, thus demonstrating its ability to function as an autonomous element. The results of this study suggest that D. willistoni may have served as the donor species in the horizontal transfer of P elements to D. melanogaster.

Bacterial Cell Division

Abstract: ▪ Abstract Formation of the bacterial division septum is catalyzed by a number of essential proteins that assemble into a ring structure at the future division site. Assembly of proteins into the c...

Walking Together: A Paradigmatic Social Phenomenon

Abstract: The everyday concept of a social group is approached by examining the concept of going for a walk together, an example of doing something together, or "shared action". Two analyses requiring shared personal goals are rejected, since they fail to explain how people walking together have obligations and rights to appropriate behavior, and corresponding rights of rebuke. An alternative account is proposed: those who walk together must constitute the "plural subject" of a goal (roughly, their walking alongside each other). The nature of plural subjecthood, the thesis that social groups are plural subjects, and the relation of these ideas to Rousseau's and Hobbes's, are briefly explored.

Anteromedial tibial tubercle transfer without bone graft

Abstract: We followed 30 patients for more than 2 years after anteromedial tibial tubercle transfer for persistent patellofemoral pain associated with patellar articular degeneration Twelve of these patients were followed more than 5 years We report 93% good and excellent results subjectively and 89% good and excellent results objectively The quality of improvement was sustained in all 12 of the patients who were evaluated again after more than 5 years from surgery When examined separately, 75% of those patients with advanced patellar arthrosis achieved a good result; none of these patients achieved an excellent result Postoperative continuous passive motion has markedly reduced the incidence of stiffness Serious complications such as compartment syndrome, infection, and skin slough were avoided completely in 51 consecutive cases Patellofemoral contact pressure studies in five cadaver knees have shown that anteromedial tibial tubercle transfer can provide substantial reduction of patellofemoral contact stress while helping to balance medial and lateral facet pressures This surgical procedure is mechanically and clinically successful for alleviating intractable pain related to patellar malalignment and articular degeneration This procedure enables the majority of appropriately selected patients with malalignment and patellar articular degeneration to resume increased levels of activity with substantially diminished pain

Carrier system and method for the introduction of genes into mammalian cells

Abstract: A targetable gene delivery system is provided for introducing foreign genes into mammalian cells. The system employs a soluble targetable DNA complex and utilizes receptor-mediated endocytosis to endow cell specificity. The soluble DNA-carrying complex is formed by non-covalently binding a ligand conjugate with the foreign gene. The conjugate, in turn, is formed by bonding receptor-specific ligands such as asialoglycoproteins to polycations such as polylysine through covalent bonds such as disulfide bonds. The system exhibits a high degree of cell specificity and offers potential for the treatment of inherited genetic disorders.

Polymer Blends Containing Liquid Crystals: A Review

Abstract: This paper reviews the literature of polymer blends containing low and high molar mass liquid crystals. Low molar mass liquid crystals have been used as plasticizers for thermoplastic polymers and in applications such as electro-optics, optical recording media, and membranes. High molar mass liquid crystalline polymers have been primarily used in polymer blends as processing aids and as an incipient reinforcing phase for “self-reinforced” materials. This review discusses the phase behavior, rheology, and mechanical properties of these blends.

Disorders of patellofemoral alignment.

Abstract: Disorders of patellofemoral alignment. J Fulkerson;K Shea; The Journal of Bone & Joint Surgery

Metabolism of carotenoid pigments in birds.

Abstract: Carotenoid pigments are an important component in the plumage of birds. The metabolic precursors are dietary in origin but many species have the capacity to chemically modify and selectively deposit the pigments. The ensuing plumage patterns are important in communication and identification. The bright yellows, oranges, and reds are due mostly to xanthophylls; keto and hydroxy carotenes. Some are deposited unmodified (e.g., lutein) whereas others are modified chemically (canthaxanthin, astaxanthin). Early workers concentrated on demonstrating that feather carotenoids were derived from the diet and deposited selectively. Progress in defining and solving biological problems depended on advances in chemical and analytical techniques. Subsequent investigation showed that various plumage colormorphs, seasonal plumage changes or colors in common mutant, were due to relatively simple chemical changes in carotenoids but had profound biological consequences. Equally important was the realization that many of these processes were under genetic control. Validation came from feeding studies of flamingos and finches. Recent studies have employed the plumage carotenoids to test hypotheses of genetic divergence, to relate plumage color to environmental process, and to demonstrate the influence of synthetic changes on color. Understanding the processes has advanced with the introduction of high-resolution separation techniques and the ability to determine both conformation and absolute configuration. The next steps will be in the direction of understanding the enzymatic modification, transport, and tissue selectivity of feather carotenoids.

Comparison of Cognitive-Behavioral, Relaxation, and Self-Modeling Interventions for Depression among Middle-School Students.

Abstract: The efficacy of short-term cognitive-behavioral therapy, relaxation training, and self-modeling interventions for the treatment of depression among middle school students was investigated. Sixty-ei...

One More Time: Do Female and Male Managers Differ?

Abstract: Executive Overview There has been a dramatic change in the “face” of management over the last two decades. That face is now female more than one-third of the time. What are the implications for the practice of management? Most of us are aware of traditional stereotypes about male-female differences, but how well do these stereotypes apply to the managerial ranks? Do male and female managers differ in their basic responses to work situations and their overall effectiveness (and if so, in what ways), or are they really quite similar? This article reviews the research evidence gathered on these questions since women managers were first noticed by researchers in the mid-1970s. The implications of this review are discussed, and contrasted with recommendations offered in recent articles by Jan Grant in Organizational Dynamics and Felice Schwartz in Harvard Business Review. The title of the article is styled after the title of Frederick Herzberg's classic 1968 Harvard Business Review article, “One More Time: How...

Alkylmercury species in the equatorial Pacific

Abstract: HIGH levels of mercury in piscivorous fish constitute a long-standing health hazard1–6. Monomethyl mercury, the main form of mercury in fish, is more toxic than inorganic mercury. But although something is known of the ability of organisms to methylate mercury7,8, the sources, synthesis and fate of methyl mercury in aquatic waters are not well understood. Inorganic and alkylated mercury has been studied in natural waters9–11, precipitation and the atmosphere12,13. We now report evidence of monomethyl and dimethyl mercury in the low-oxygen waters of the equatorial Pacific. The presence of these species has important implications for our understanding of the biogeochemical cycling of mercury in the marine environment. Although the source of monomethyl mercury in open-ocean fish is still unknown, our data show that a pathway exists for the accumulation of methylated mercury in marine pelagic fish.

Linear intensity dependence of a two-photon transition rate.

Abstract: At low intensities the rate of two-photon transitions in an atom driven by parametrically down-converted light may be linear in intensity. Such a violation of the usual perturbative law arises from strong correlations between pairs of photons.

Biphasic effects of prostaglandin E2 on bone formation in cultured fetal rat calvariae: interaction with cortisol.

Abstract: Previous studies have shown that prostaglandin E2 (PGE2) has both inhibitory and stimulatory effects on the incorporation of proline into collagenase-digestible protein (CDP) in cultured fetal rat calvaria. The present studies were undertaken to analyze further these biphasic effects of PGE2. PGE2 increased [3H]thymidine incorporation at 24 h, and this effect was enhanced in the presence of cortisol (10-8 and 10-7M). An inhibitory effect on CDP labeling was observed at 96 h with PGE2 (10-6 M) in the absence or presence of indomethacin (10-6 M), but not in the presence of cortisol (10-8 or 10-7 M). When the central osteoblast-rich bone and periosteum were analyzed separately, the inhibitory effect of PGE2, with or without indomethacin, was confined to the central bone. Addition of aphidicolin (30 μM), an inhibitor of cell replication, did not prevent the inhibitory effect of PGE2 on CDP labeling. Analysis of labeled collagen by polyacrylamide gel electrophoresis showed a decrease in labeling of type I coll...

Host–parasitoid associations in patchy environments

Abstract: STUDIES of insect host–parasitoid interactions have contributed much to the consensus that spatial patchiness is important in the regulation of natural populations1–5. A variety of theoretical models predict that host and parasitoid populations, although unstable in the absence of environmental heterogeneity, may persist at roughly steady overall densities in a patchy environment owing to variation in levels of parasitism from patch to patch. Observed patterns of parasitism, however, have a variety of forms (with variation in attack rates among patches depending directly or indirectly on host density, or showing variation uncorrelated with host density). There is some confusion about the dynamical consequences of these different forms6,7. Here we first show how the dynamical effects of all these forms of environmental heterogeneity can be assessed by a common criterion. This 'CV2 > 1 rule' states that the overall population densities will remain roughly steady from generation to generation if the coefficient of variation squared (CV2) of the density of searching parasitoids in the vicinity of each host exceeds approximately unity. By partitioning CV2 into components, we show that both direct and inverse patterns of dependence on host density, and density-independent patterns, all contribute to population regulation in the same way. Second, we show how a maximum-likelihood method can be applied to the kind of field data that are usually available (that is, percentage parasitism versus local host density) to estimate the components of CV2. This analysis indicates that heterogeneity is large enough to stabilize dynamics in 9 of 34 published studies, and that density-independent heterogeneity is the main factor in most cases.

Improved Fourier transform profilometry for the automatic measurement of 3D object shapes

Abstract: By using a defocused optical field with a Ronchi grating to get a quasi-sine optical field and by using a grating ii phase shifting technique, the fundamental spectrum modulated by the object height distribution can theoretically be extended from 0 to 2f0 ( f0 is the carrier frequency of the optical field) without overlapping the zero component and other higher spectra. Consequently, the measurable slope of height variation can be extended to nearly three times that of the unimproved Fourier transform profilometry method. This paper gives the theory and experiment results of the improved Fourier transform profilometry.

Assessment of four ambulatory blood pressure monitors and measurements by clinicians versus intraarterial blood pressure at rest and during exercise

Abstract: The accuracy of 4 different ambulatory blood pressure (BP) monitors was assessed by comparing them to simultaneous intraarterial BP (contralateral brachial artery) during rest, isometric and dynamic (bicycle) exercise in 48 hypertensive patients undergoing invasive hemodynamic evaluation. The differences between the intraarterially determined BP and values obtained by the various monitors were then compared to differences between BP measured directly and by 2 clinicians using a standard mercury column in 10 additional hypertensive patients. The monitors studied were the Accutracker II (auscultatory with mandatory electrocardiographic gating), Colin ABPM 630 (auscultatory or oscillometric), Del Mar Pressurometer IV (auscultatory with optional electrocardiographic gating) and SpaceLabs 90202 (oscillometric). During rest, the differences between intraarterially and clinician-determined systolic and diastotic BP were 4 ± 8 and −4 ± 6 mm Hg, respectively. The Accutracker II and Colin ABPM 630 using the auscultatory method showed less disparity and closer limits of agreement (2 standard deviations of the mean difference) with intraarterial BP than the clinicians' measurements, whereas the other units showed similar or greater limits of agreement. During both isometric and dynamic exercise, mean BP differences between intraarterial and clinician determinations were similar to those at rest but the limits of agreement increased. The limits of agreement between intraarterial and monitor-derived BP also increased during exercise compared to differences observed at rest. The Accutracker II and Colin ABPM 630 using the auscultatory method had limits of agreement with intraarterial BP that were either similar to or less than the clinicians', whereas the Colin monitor using the oscillometric method and the Del Mar Pressurometer IV showed greater disparity. The SpaceLabs unit produced only error codes in 8 of 10 subjects during dynamic exercise. Thus, these data show that at rest, noninvasive ambulatory BP monitors are similar in accuracy to clinicians in BP determination but during exercise there are differences among the monitors that make some of them unsuitable for measurements while in motion.