Showing papers by "University of Rochester published in 1995"

Integration of visual and linguistic information in spoken language comprehension

Abstract: Psycholinguists have commonly assumed that as a spoken linguistic message unfolds over time, it is initially structured by a syntactic processing module that is encapsulated from information provided by other perceptual and cognitive systems. To test the effects of relevant visual context on the rapid mental processes that accompany spoken language comprehension, eye movements were recorded with a head-mounted eye-tracking system while subjects followed instructions to manipulate real objects. Visual context influenced spoken word recognition and mediated syntactic processing, even during the earliest moments of language processing.

Psychological Needs and the Facilitation of Integrative Processes

Abstract: The assumption that there are innate integrative or actualizing tendencies underlying personality and social development is reexamined. Rather than viewing such processes as either nonexistent or as automatic, I argue that they are dynamic and dependent upon social-contextual supports Pertaining to basic human psychological needs. To develop this viewpoint, I conceptually link the notion of integrative tendencies to specific developmental processes, namely intrinsic motivation; internalization; and emotional integration. These processes are then shown to be facilitated by conditions that fulfill psychological needs for autonomy, competence, and relatedness, and forestalled within contexts that frustrate these needs. Interactions between psychological needs and contextual supports account, in part, for the domain and situational specificity of motivation, experience, and relative integration. The meaning of psychological needs (vs. wants) is directly considered, as are the relations between concepts of integration and autonomy and those of independence, individualism, efficacy, and cognitive models of “multiple selves.”

Digital Video Processing

Abstract: Over the years, thousands of engineering students and professionals relied on Digital Video Processing as the definitive, in-depth guide to digital image and video processing technology. Now, Dr. A. Murat Tekalp has completely revamped the first edition to reflect todays technologies, techniques, algorithms, and trends. Digital Video Processing, Second Edition, reflects important advances in image processing, computer vision, and video compression, including new applications such as digital cinema, ultra-high-resolution video, and 3D video. This edition offers rigorous, comprehensive, balanced, and quantitative coverage of image filtering, motion estimation, tracking, segmentation, video filtering, and compression. Now organized and presented as a true tutorial, it contains updated problem sets and new MATLAB projects in every chapter. Coverage includes Multi-dimensional signals/systems: transforms, sampling, and lattice conversion Digital images and video: human vision, analog/digital video, and video quality Image filtering: gradient estimation, edge detection, scaling, multi-resolution representations, enhancement, de-noising, and restoration Motion estimation: image formation; motion models; differential, matching, optimization, and transform-domain methods; and 3D motion and shape estimation Video segmentation: color and motion segmentation, change detection, shot boundary detection, video matting, video tracking, and performance evaluation Multi-frame filtering: motion-compensated filtering, multi-frame standards conversion, multi-frame noise filtering, restoration, and super-resolution Image compression: lossless compression, JPEG, wavelets, and JPEG2000 Video compression: early standards, ITU-T H.264/MPEG-4 AVC, HEVC, Scalable Video Compression, and stereo/multi-view approaches

Metabolic effects of metformin in non-insulin-dependent diabetes mellitus.

Abstract: Background The metabolic effects and mechanism of action of metformin are still poorly understood, despite the fact that it has been used to treat patients with non-insulin-dependent diabetes mellitus (NIDDM) for more than 30 years. Methods In 10 obese patients with NIDDM, we used a combination of isotope dilution, indirect calorimetry, bioimpedance, and tissue-balance techniques to assess the effects of metformin on systemic lactate, glucose, and free-fatty-acid turnover; lactate oxidation and the conversion of lactate to glucose; skeletal-muscle glucose and lactate metabolism; body composition; and energy expenditure before and after four months of treatment. Results Metformin treatment decreased the mean (±SD) glycosylated hemoglobin value from 13.2±2.2 percent to 10.5±1.6 percent (P<0.001) and reduced fasting plasma glucose concentrations from 220±41 to 155±28 mg per deciliter (12.2±0.7 to 8.6±0.5 mmol per liter) (P<0.001). Although resting energy expenditure did not change, the patients lost 2.7±1.3 ...

Observation of top quark production in p̄p collisions with the collider detector at fermilab

Abstract: We establish the existence of the top quark using a $67{\mathrm{pb}}^{\ensuremath{-}1}$ data sample of $\overline{p}p$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ collected with the Collider Detector at Fermilab (CDF). Employing techniques similar to those we previously published, we observe a signal consistent with $t\overline{t}$ decay to $\mathrm{WWb}\overline{b}$, but inconsistent with the background prediction by $4.8\ensuremath{\sigma}$. Additional evidence for the top quark is provided by a peak in the reconstructed mass distribution. We measure the top quark mass to be $176\ifmmode\pm\else\textpm\fi{}8(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}10(\mathrm{syst})\mathrm{GeV}{/c}^{2}$, and the $t\overline{t}$ production cross section to be ${6.8}_{\ensuremath{-}2.4}^{+3.6}\mathrm{pb}$.

A developmental psychopathology perspective on child abuse and neglect

Abstract: Objective The purpose of this review is to conceptualize child abuse and neglect within a developmental psychopathology perspective. Toward this end, issues of definition and epidemiology, etiology, and sequelae are addressed. Method Research and theory on child abuse and neglect with relevance to a developmental perspective is reviewed. Results Considerable progress has been made in our understanding of the etiology and consequences of child abuse and neglect. Less progress has been made in utilizing this knowledge to inform treatment efforts. Conclusions Incorporation of a developmental psychopathology perspective into efforts to understand and ameliorate the adverse effects of child abuse and neglect holds considerable promise for advancing research and intervention in the area of child maltreatment. The importance of providing comprehensive and coordinated services that incorporate knowledge of how maltreated youngsters negotiate stage-salient issues of development is stressed. The provision of child-focused treatment, parent-based models of intervention, and ecologically driven approaches to prevention all can benefit from an understanding of the adverse effects that maltreatment exerts on the process of development.

Collapsible anvil assembly and applicator instrument

Abstract: A collapsible anvil assembly and applicator instrument for use with a surgical stapler. The collapsible anvil assembly includes an anvil shaft and a plurality of anvil segments, having staple clinching buckets thereon, flexibly affixed to the anvil shaft which are movable between a collapsed or radially inwardly deflected condition and an expanded or radially outwardly deflected condition. Immobilizing means in the form of an axially slidable locking ring is provided to fix and maintain the anvil segments in the expanded condition. Mounting element are also provided for subsequent detachable mounting of the anvil assembly on a surgical stapler. The collapsible anvil assembly may also include a suction purse stringing device which attracts and holds a surrounding tissue section within the anvil segments. Additionally, an axially slidable tissue holding ring or snap cap is provided to lock the held tissue section within the anvil segments.

Specific and General Knowledge, and Organizational Structure

Abstract: Specific knowledge is knowledge that is costly to transfer among agents and general knowledge is knowledge that is inexpensive to transmit. Because specific knowledge is costly to transfer, getting it used in decision-making requires decentralizing many decision rights in both the economy and in firms. Such delegation in turn creates two problems: the rights assignment problem (determining who should exercise a decision right), and the control or agency problem (ensuring that self-interested decision agents exercise their rights in a way that contributes to the organizational objective).

Evolution and Phylogeny of Wolbachia: Reproductive Parasites of Arthropods

Abstract: Wolbachia are cytoplasmically inherited bacteria found in reproductive tissues of many arthropod species. These bacteria are associated with reproductive alterations in their hosts, including parthenogenesis, reproductive incompatibility and feminization. A fine-scale phylogenetic analysis was done using DNA sequences from ftsZ, a rapidly evolving bacterial cell-cycle gene. fsZ sequences were determined for 38 different Wolbachia strains from 31 different species of insects and one isopod. The following results were found: (i) there are two major division of Wolbachia (A and B) which diverged 58-67 millions years before present based upon synonymous substitution rates; (ii) a general concordance is found between the ftsZ and 16S rDNA phylogenies, indicating that these represent bacterial strain (rather than simply gene) phylogenies; however, a possible example of recombination between A and B division bacteria may have occurred in the feminizing Wolbachia present in an isopod; (iii) extensive horizontal transmission of Wolbachia has occurred between insect taxa, including different insect orders; one strain in particular (designated Adm) shows extensive recent horizontal transmission; (iv) there is an association between the Wolbachia found in a parasitic wasp (Nasonia) and its fly host (Protocalliphora), suggesting exchange of bacteria between these species; (v) parthenogenesis induction has evolved several times among the Wolbachia; and (vi) some insects harbour infections with more than one Wolbachia strain, even within individual insects.

The G-protein-gated atrial K+ channel IKACh is a heteromultimer of two inwardly rectifying K(+)-channel proteins.

Abstract: Heart rate is slowed in part by acetylcholine-dependent activation of a cardiac potassium (K+) channel, IKACh. Activated muscarinic receptors stimulate IKACh via the G-protein beta gamma-subunits. It has been assumed that the inwardly rectifying K(+)-channel gene, GIRK1, alone encodes IKACh. It is now shown that IKACh is a heteromultimer of two distinct inwardly rectifying K(+)-channel subunits, GIRK1 and a newly cloned member of the family, CIR.

Coherence and congruence: two aspects of personality integration.

Abstract: Coherence and congruence-based measures of personality integration were related to a variety of healthy personality characteristics. Functional coherence was denned as occurring when participants' "personal strivings" (R. A. Emmons, 1986) help bring about each other or help bring about higher level goals. Organismic congruence was denned as occuring when participants strive for selfdetermined reasons or when strivings help bring about intrinsic rather than extrinsic higher level goals. Study 1 found the integration measures were related to each other and to inventory measures of health and well-being. Study 2 showed that these goal integration measures were also related to role system integration and were prospective predictors of daily mood, vitality, and engagement in meaningful as opposed to distracting activities.

Scaling theory of polyelectrolyte solutions

Abstract: We extend and generalize the scaling picture of de Gennes et al. and Pfeuty to both unentangled and entangled regimes of intrinsically flexible polyelectrolyte solutions. In semidilute solution the electrostatic persistence length of a polyelectrolyte is assumed to be proportional to the Debye screening length. If the salt concentration is low, the unentangled semidilute concentration regime spans three to four decades in polymer concentration. In this regime the dynamics of the chain is Rouse-like with viscosity weakly increasing with concentration η∼c 1/2 (Fuoss law), relaxation time decreasing with concentration τ Rouse ∼c -1/2 , and diffusion coefficient independent of concentration. Polyelectrolytes should form entanglements at the same relative viscosity as neutral polymer solutions (η≅50η s ). In the entangled regime of salt-free polyelectrolytes we predict the viscosity η∼c 3/2 , relaxation time to be independent of concentration, and diffusion coefficient D self ∼c -1/2 . Our predictions are found to compare favorably with experiments

Are Racial Stereotypes Really Fading? The Princeton Trilogy Revisited

Abstract: In this article, the authors identify three methodological short-comings of the classic Princeton trilogy studies: (a) ambiguity of the instructions given to respondents, (b) no assessment of respondents' level of prejudice, and (c) use of an outdated list of adjectives. These shortcomings are addressed in the authors' assessment of the stereotype and personal beliefs of a sample of University of Wisconsin students. In contrast to the commonly espoused fading stereotype proposition, data suggest that there exists a consistent and negative contemporary stereotype of Blacks. Comparing the data from the Princeton trilogy studies with those of the present study, the authors conclude that the Princeton trilogy studies actually measured respondents' personal beliefs, not (as typically assumed) their knowledge of the Black stereotype. Consistent with Devine's model, high- and low-prejudiced individuals did not differ in their knowledge of the stereotype of Blacks but diverged sharply in their endorsement of the ...

The Population Genetics of Speciation: The Evolution of Hybrid Incompatibilities

Abstract: Speciation often results from the accumulation of "complementary genes," i.e., from genes that, while having no deleterious effect within species, cause inviability or sterility when brought together with genes from another species. Here I model speciation as the accumulation of genic incompatibilities between diverging populations. Several results are obtained. First, and most important, the number of genic incompatibilities between taxa increases much faster than linearly with time. In particular, the probability of speciation increases at least as fast as the square of the time since separation between two taxa. Second, as Muller realized, all hybrid incompatibilities must initially be asymmetric. Third, at loci that have diverged between taxa, evolutionarily derived alleles cause hybrid problems far more often than ancestral alleles. Last, it is "easier" to evolve complex hybrid incompatibilities requiring the simultaneous action of three or more loci than to evolve simple incompatibilities between pairs of genes. These results have several important implications for genetic analyses of speciation.

Script, Counterscript, and Underlife in the Classroom: James Brown versus Brown v. Board of Education

Abstract: In this article, Kris Gutierrez, Betsy Rymes, and Joanne Larson demonstrate how power is constructed between the teacher and students. The authors identify the teacher's monologic script, one that potentially stifles dialogue and interaction and that reflects dominant cultural values, and the students' counterscripts, formed by those who do not comply with the teacher's view of appropriate participation. The authors then offer the possibility of a "third space" — a place where the two scripts intersect, creating the potential for authentic interaction to occur. Using an analysis of a specific classroom discourse, the authors demonstrate how, when such potential arises, the teacher and students quickly retreat to more comfortable scripted places. The authors encourage the join construction of a new sociocultural terrain, creating space for shifts in what counts as knowledge and knowledge representation.

Inclusion body myositis and myopathies.

Abstract: Preface Part I. Overview of Pathologic and Pathogenic Comparison Between Sporadic Inclusion-Body Myositis and Hereditary Inclusion-Body Myopathies: 1. Newest approaches to diagnosis and pathogenesis of sporadic inclusion-body myositis and hereditary inclusion-body myopathies, including molecular-pathologic similarities to Alzheimer disease Part II. Historical Perspective: 2: Evolving concepts of inclusion-body myositis Part III. Sporadic Inclusion-Body Myositis - Clinical and Diagnostic Considerations: 3: Sporadic inclusion-body myositis: Clinical and laboratory features and diagnostic criteria 4: Inclusion-body myositis: natural history 5: Uncommon clinico-pathological forms of sporadic inclusion-body myositis: Report of four cases 6: Inclusion-body myositis: pathological changes 7: Unusual pathological forms of inclusion-body myositis, and neuromuscular disorders with IBM-like changes 8: Electrophysiological findings in inclusion-body myositis 9: Genetic factors in sporadic inclusion-body myositis Part IV. Hereditary Inclusion-Body Myopathies - Clinical and Diagnostic Considerations: 10: Hereditary inclusion-body myopathy in Jews of Persian origin: Clinical and laboratory data 11. Hereditary inclusion-body myopathy (h-IBM) with quadriceps sparing: epidemiology and genetics 12: Familial autosomal-recessive inclusion-body myositis with asymptomatic leukoencephalopathy 13: Welander distal myopathy - clinical, pathophysiological, and molecular aspects 14. Tibial muscular dystrophy - clinical, genetic, and morphological characteristics 15. Distal myopathy with rimmed vacuoles, inclusion-body myositis and related disorders in Japan 16. Inclusion-body myopathies 17. Is the muscle fiber in inclusion body-myositis an antigen-presenting cell of an innocent bystander? 18. Viruses, immunodeficiency and inclusion-body myositis 19. Myonuclear abnormalities may play a central role in the pathogenesis of muscle fiber damage in inclusion-body myositis 20. Nuclear degeneration and rimmed vacuole formation in neuromuscular disorders 21. Mitochondrial alterations in sporadic inclusion-body myositis 22. mtDNA analysis in muscle of patients with sporadic inclusion-body myopathy Part V. Treatment: 23. Evaluation of treatment for sporadic inclusion-body myositis 24. Personal experience in treating sporadic inclusion-body myositis Subject index.

A framework for analysis of data quality research

Abstract: Organizational databases are pervaded with data of poor quality. However, there has not been an analysis of the data quality literature that provides an overall understanding of the state-of-art research in this area. Using an analogy between product manufacturing and data manufacturing, this paper develops a framework for analyzing data quality research, and uses it as the basis for organizing the data quality literature. This framework consists of seven elements: management responsibilities, operation and assurance costs, research and development, production, distribution, personnel management, and legal function. The analysis reveals that most research efforts focus on operation and assurance costs, research and development, and production of data products. Unexplored research topics and unresolved issues are identified and directions for future research provided. >

Memory representations in natural tasks

Abstract: The very limited capacity of short-term or working memory is one of the most prominent features of human cognition. Most studies have stressed delimiting the upper bounds of this memory in memorization tasks rather than the performance of everyday tasks. We designed a series of experiments to test the use of short-term memory in the course of a natural hand-eye task where subjects have the freedom to choose their own task parameters. In this case subjects choose not to operate at the maximum capacity of short-term memory but instead seek to minimize its use. In particular, reducing the instantaneous memory required to perform the task can be done by serializing the task with eye movements. These eye movements allow subjects to postpone the gathering of task-relevant information until just before it is required. The reluctance to use short-term memory can be explained if such memory is expensive to use with respect to the cost of the serializing strategy.

Emotions and emotion regulation in developmental psychopathology

Abstract: The understanding of emotions possesses important implications for elucidating normal as well as abnormal development. The contributions that the emotions have made for enhancing our understanding of psychopathology have been evident throughout history. In this article, an overview of the historical links between the emotions and psychopathology is presented. Despite its rich history, much contemporary theory and research on emotions has been conducted primarily within a nonpathology perspective. In recent decades, investigators have become more interested in examining the role and development of the emotions in atypical populations. It has been argued that the modularity of the emotions system requires a developmental model of emotion regulation.

A perpetual cascade of cytokines postirradiation leads to pulmonary fibrosis

Abstract: PURPOSE Radiation-induced pulmonary reactions have classically been viewed as distinct phases--acute pneumonitis and, later, fibrosis--occurring at different times after irradiation and attributed to different target cell populations. We prefer to view these events as a continuum, with no clear distinction between the temporal sequence of the different pulmonary reactions; the progression is the result of an early activation of an inflammatory reaction, leading to the expression and maintenance of a cytokine cascade. In the current study, we have examined the temporal and spatial expression of cytokine and extracellular matrix messenger ribonucleic acid (mRNA) abundance in fibrosis-sensitive mice after thoracic irradiation. METHODS AND MATERIALS Radiation fibrosis-prone (C57BL/6) mice received thoracic irradiation of 5 and 12.5 Gy. At Day 1, and 1, 2, 8, 16, and 24 weeks after treatment, animals were killed and lung tissue processed for light microscopy and isolation of RNA. Expression of cytokine and extracellular matrix mRNA abundance was evaluated by slot-blot analysis and cellular localization by in situ hybridization and immunochemistry. RESULTS One of the cytokines responsible for the inflammatory phase (IL-1 alpha) is elevated at 2 weeks, returns to normal baseline values, then increases at 8 weeks, remaining elevated until 26 weeks when lung fibrosis appears. Transforming growth factor-beta (TGF beta), a proliferative cytokine, is elevated at 2 weeks, persists until 8 weeks, and then returns to baseline values. In parallel with the cytokine cascade, the fibrogenic markers for CI/CIII/IV (collagen genes) correlate by showing a similar early and then later elevation of activity. For instance, the collagen gene expression of CI/CIII is a biphasic response with an initial increase at 1-2 weeks that remits at 8 weeks, remains inactive from 8 to 16 weeks, and then becomes elevated at 6 months when collagen deposition is recognized histopathologically. CONCLUSION These studies clearly demonstrate the early and persistent elevation of cytokine production following pulmonary irradiation. The temporal relationship between the elevation of specific cytokines and the histological and biochemical evidence of fibrosis serves to illustrate the continuum of response, which, we believe, underlies pulmonary radiation reactions and supports the concept of a perpetual cascade of cytokines produced immediately after irradiation, prompting collagen genes to turn on, and persisting until the expression of late effects becomes apparent pathologically and clinically.

Association of particulate air pollution and acute mortality: involvement of ultrafine particles?

Abstract: Recent epidemiological studies show an association between particulate air pollution and acute mortality and morbidity down to ambient particle concentrations below 100 micrograms/m3. Whether this association also implies a causality between acute health effects and particle exposure at these low levels is unclear at this time; no mechanism is known that would explain such dramatic effects of low ambient particle concentrations. Based on results of our past and most recent inhalation studies with ultrafine particles in rats, we propose that such particles, that is, particles below approximately 50 nm in diameter, may contribute to the observed increased mortality and morbidity In the past we demonstrated that inhalation of highly insoluble particles of low intrinsic toxicity, such as TiO2, results in significantly increased pulmonary inflammatory responses when their size is in the ultrafine particle range, approximately 20 nm in diameter. However, these effects were not of an acute nature and occurred only after prolonged inhalation exposure of the aggregated ultrafine particles at concentrations in the milligrams per cubic meter range. In contrast, in the course of our most recent studies with thermodegradation products of polytetrafluoroethylene (PTFE) we found that freshly generated PTFE fumes containing singlet ultrafine particles (median diameter 26 nm) were highly toxic to rats at inhaled concentrations of 0.7-1.0 x 10(6) particles/cm3, resulting in acute hemorrhagic pulmonary inflammation and death after 10-30 min of exposure. We also found that work performance of the rats in a running wheel was severely affected by PTFE fume exposure. These results confirm reports from other laboratories of the highly toxic nature of PTFE fumes, which cannot be attributed to gas-phase components of these fumes such as HF, carbonylfluoride, or perfluoroisobutylene, or to reactive radicals. The calculated mass concentration of the inhaled ultrafine PTFE particles in our studies was less than 60 micrograms/m3, a very low value to cause mortality in healthy rats. Aging of the fumes with concomitant aggregation of the ultrafine particles significantly decreases their toxicity. Since ultrafine particles are always present in the urban atmosphere, we suggest that they play a role in causing acute lung injury in sensitive parts of the population.