cssi/SciSciGPT-SciSciNet huggingface dataset:
“TUMBLR TOLD ME…”: THE POLITICAL AND METHODOLOGICAL SIGNIFICANCE OFCONCEPTUALIZING SOCIAL MEDIA PLATFORMS AS LIVING ACTORS

This paper takes up the question of how “platform” can be understood when it comes to studies of digital discourse. I posit that this is an empirical and ethnographic question, rather than a purely theoretical one. Regardless of how scholars theorize social media platforms and other technologies, the people interacting with those technologies already have their own emic conceptualizations of what that technology is and how it functions and those understandings shape their social media experiences. This paper aims to explore the stakes of such local conceptualizations. I argue that many of tumblr.com's most active users conceptualize the social media platform as a living actor — a dynamic and agentive entity with whom these young people interact, rather than a space on which they interact or a medium through which they interact. Attending to this particular understanding of Tumblr-as-actor is crucial because it has so intimately shaped the processes by which my research participants have come to take up new political-ethical commitments and identities through their engagement with the platform. However, I suggest that new methodological approaches for the study of digital discourse are required if scholars are to truly take seriously an understanding of platform as agentive figure. To this end, I argue for the use of audio-visual screen capture technologies that concurrently record the content on a screen alongside the bodies of users themselves for analyzing in-the-moment interactions between user and platform.
Mapping features of pathological exercise using hierarchical-dimensional modeling.

OBJECTIVE Pathological exercise is common among those with eating disorders and has typically been characterized as excessive, compulsive, or compensatory in nature. Little is known about how pathological exercise is associated with other eating disorder behaviors or personality traits, or whether these associations differ between men and women. METHOD We used hierarchical dimensional modeling in three samples, including college women (N = 205), women with eating psychopathology (N = 268), and college men (N = 235), to examine latent associations between pathological exercise and eating disorder psychopathology, namely compulsivity, emotion regulation, and body dissatisfaction. RESULTS Using Goldberg's (2006) "bass-ackwards" method, we identified separate 10-factor solutions (women) or an 11-factor solution (men). A distinct muscle building factor arose in the three-factor solution for men, and it also notably arose in the six- and eight-factor solutions for community and college women, respectively, highlighting an important understudied motivation factor in both healthy and pathological exercise. Each solution accounted for 64.8% (college women), 51.9% (women with eating psychopathology), and 43.9% (college men) of the variance in excessive exercise, respectively. DISCUSSION Findings indicate that pathological exercise is associated with different psychological traits (e.g., poor emotion regulation, compulsivity) across populations, and such differences may necessitate unique treatment approaches tailored accordingly.
Translating genetic association of lipid levels for biological and clinical application

This review focuses on the foundational evidence from the last two decades of lipid genetics research and describes the current status of data-driven approaches for transethnic GWAS, fine-mapping, transcriptome informed fine-mapping, and disease prediction. Current lipid genetics research aims to understand the association mechanisms and clinical relevance of lipid loci as well as to capture population specific associations found in global ancestries. Recent genome-wide trans-ethnic association meta-analyses have identified 118 novel lipid loci reaching genome-wide significance. Gene-based burden tests of whole exome sequencing data have identified three genes—PCSK9, LDLR, and APOB—with significant rare variant burden associated with familial dyslipidemia. Transcriptome-wide association studies discovered five previously unreported lipid-associated loci. Additionally, the predictive power of genome-wide genetic risk scores amalgamating the polygenic determinants of lipid levels can potentially be used to increase the accuracy of coronary artery disease prediction. Lipids are one of the most successful group of traits in the era of genome-wide genetic discovery for identification of novel loci and plausible drug targets. However, a substantial fraction of lipid trait heritability remains unexplained. Further analysis of diverse ancestries and state of the art methods for association locus refinement could potentially reveal some of this missing heritability and increase the clinical application of the genomic association results.
Optical beam transformation using holographic spatial light modulators

Spatial light modulators produce beams with a desired phase pattern, which directly affects the beam’s power spatial distribution. We demonstrate an approach for creating holographic spatial light modulators, which are permanently recorded in a photosensitive glass and do not require electric power in order to operate. The essence of the approach is that by means of holographic recording, an arbitrary phase pattern is encoded into a transmitting volume Bragg grating. Upon Bragg reconstruction, the phase pattern is reconstructed in the diffracted beam. These spatial light modulators are tunable and could be achromatic in broad spectral range.
Missing trace reconstruction for 2D land seismic data with randomized sparse sampling

ABSTRACTAcquisition of high-quality land seismic data requires (expensive) dense source and receiver geometries to avoid aliasing-related problems. Alternatively, acquisition using the concept of c...
Spatial Decision Support Systems

This article is a revision of the previous edition article by G. Rushton, volume 22, pp. 14785–14788, © 2001, Elsevier Ltd.
Mode Conversions in Ionospheric Modification Experiments

We investigate resonance excitation of electrostatic and electromagnetic electron cyclotron harmonic waves by mode conversion during the recent ionospheric F-region modification experiments at Tromso (Norway) and Arecibo (Puerto Rico). Frequency band width for quenching of DM feature in the electromagnetic emission spectra from ionosphere is found to be about a few kHz which is in good agreement with the experimental results.
Incremental learning of perceptual categories for open-domain sketch recognition

Most existing sketch understanding systems require a closed domain to achieve recognition. This paper describes an incremental learning technique for open-domain recognition. Our system builds generalizations for categories of objects based upon previous sketches of those objects and uses those generalizations to classify new sketches. We represent sketches qualitatively because we believe qualitative information provides a level of description that abstracts away details that distract from classification, such as exact dimensions. Bayesian reasoning is used in building representations to deal with the inherent uncertainty in perception. Qualitative representations are compared using SME, a computational model of analogy and similarity that is supported by psychological evidence, including studies of perceptual similarity. We use SEQL to produce generalizations based on the common structure found by SME in different sketches of the same object. We report on the results of testing the system on a corpus of sketches of everyday objects, drawn by ten different people.
Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

Exposure to environmental tobacco smoke (ETS), which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies. Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing COPD. Participants were recruited from all 48 contiguous U.S. states by random digit dialing. Lifetime ETS exposure was ascertained by structured telephone interview. We used a standard epidemiologic approach to define COPD based on a self-reported physician diagnosis of chronic bronchitis, emphysema, or COPD. Higher cumulative lifetime home and work exposure were associated with a greater risk of COPD. The highest quartile of lifetime home ETS exposure was associated with a greater risk of COPD, controlling for age, sex, race, personal smoking history, educational attainment, marital status, and occupational exposure to vapors, gas, dusts, or fumes during the longest held job (OR 1.55; 95% CI 1.09 to 2.21). The highest quartile of lifetime workplace ETS exposure was also related to a greater risk of COPD (OR 1.36; 95% CI 1.002 to 1.84). The population attributable fraction was 11% for the highest quartile of home ETS exposure and 7% for work exposure. ETS exposure may be an important cause of COPD. Consequently, public policies aimed at preventing public smoking may reduce the burden of COPD-related death and disability, both by reducing direct smoking and ETS exposure.
An Aperitif on Arbitrage

An is an investment opportunity arbitrage opportunity that is guaranteed not to result in a loss and may (with positive probability) result in a gain. We have remarked that if an arbitrage opportunity exists, then prices will be adjusted to eliminate that opportunity.
Physiological Responses to Cachectin

Mammals infected with parasitic, bacterial or viral organisms or bearing tumours characteristically display a catabolic state and weight loss which can advance to cachexia (or wasting), shock and death. Although the phenomenon is commonly observed in many parasitic diseases its mechanism is not understood. We have identified and isolated a macrophage protein, cachectin, as the molecule that may be responsible for cachexia and shock. Cachectin is produced by macrophages in response to endotoxin or a number of other bacterial or protozoal products. The released cachectin acts as a hormone, binding to specific high affinity receptors and eliciting biological responses. In the adipocyte anabolic enzymes such as lipoprotein lipase are suppressed through the selective inhibition of mRNA production. An intriguing aspect of cachectin is its pivotal role in the pathogenesis of endotoxin-induced shock. Cachectin causes fever and anorexia and can induce lethal shock and tissue injury in experimental animals. During its chemical characterization cachectin was shown to be identical to tumour necrosis factor (TNF), a macrophage protein that kills tumour cells. This finding emphasizes the extensive range of effects associated with this protein. Cachectin has many properties in common with interleukin 1 but binds to a different receptor and lacks structural homology. Presumably, low levels of cachectin help the host in its battle to remove invasive pathogens, but extensive production of cachectin can lead to shock and catabolic stress hormone responses. These findings have added a new dimension to the biological properties of cachectin, its production, and its role in cachexia and shock.
Dialects, World Englishes and Education: Understanding Literacy From a Global Perspective

TESOL Quarterly welcomes evaluative reviews of publications relevant to TESOL professionals. Dialects, Englishes, Creoles, and Education Shondel Nero Linguistic Diversity And Teaching Nancy Commins and Ofelia Miramontes
The Shaping of Deduction in Greek Mathematics: A Study in Cognitive History

Introduction: a specimen of Greek mathematics 1. The lettered diagram 2. The pragmatics of letters 3. The mathematical lexicon 4. Formulae 5. The shaping of necessity 6. The shaping of generality 7. The historical setting Appendix: the main Greek mathematicians cited in the book.
A role-based access control model for information mediation

With the increasing demands for data integration and exchange among distributed heterogeneous sources, many applications require secure interoperation and the information sharing. Mediation techniques provide an extended amalgamation of searching and querying in heterogeneous systems, but enlarge the space of possible threats to local data sources. How to encourage data sharing while enforce required protection to resources is a challenging problem. Traditional access control mechanisms and methods are inadequate to reflect the heterogeneous environment and the flexible access control requirements. This paper presents a mediation security architecture for information integration based on role-based access control (RBAC). An adorned XML model (AXM) is used to homogenize security data modeling. Security requirements of mediation systems are specified by constraints over various RBAC dimensions. An incremental security enforcement method is proposed to integrate RBAC modules into the mediation architecture. The method supports adaptive and scalable design of secure mediation systems.
Losses in Optical Waveguides

Chapters 2 and 3 have explained cutoff conditions in waveguides and described the various optical modes which can be supported. Following the question as to which modes propagate, the next most important characteristic of a waveguide is the attenuation, or loss, that a light wave experiences as it travels through the guide. This loss is generally attributable to three different mechanisms: scattering, absorption and radiation. Scattering loss usually predominates in glass or dielectric waveguides, while absorption loss is most important in semiconductors and other crystalline materials. Radiation losses become significant when waveguides are bent through a curve.
Bulk and Solution Polymerizations Reactors

A great majority of polymers are made by bulk or solution polymerizations. Even when there is a competing process, such as gas-phase or emulsion polymerization, it is likely that bulk or solution process will coexist in order to produce special product grades. A common feature of most bulk or solution polymerizations is the need to remove unreacted monomer, by-products, and solvents from a highly viscous polymer melt (ref. to devolatilization). Temperature control is a key design issue for vinyl addition polymers while control of stoichiometry, including the removal of reaction by-products, is the major design issue for condensation polymerizations. Most high volume polymers are made in continuous processes consisting of one or more reactors in series followed by a devolatilization system. Most designs are flexible so that many product grades, including random copolymers, can be made in the same equipment. Keywords: bulk polymerization; solution polymerization; copolymerization; reactor design; stirred tank reactors; tubular reactors; temperature control; solvent recycling; by-product removal
Back surface fields for GaInP/sub 2/ solar cells

Back surface passivation of the GaInP top cell in GaInP/sub 2//GaAs two-terminal tandem cells is discussed. Because of the requirement of current matching of the top and bottom cell, the top cell must be made very thin (on the order of 1 mu m), and thus proper passivation of the top cell back surface is important in achieving high open-circuit voltages. A comparison is made of two candidate top-cell back surface fields: (1) an AlGaInP quarternary, and (2) GaInP/sub 2/ grown to give a bandgap higher than that of the base of the cell. >
Perinatal regulation of the cerebral circulation: role of nitric oxide and prostaglandins.

Nitric oxide (NO) influences cerebral vascular tone both in the normal fetus and in the hypoxemic fetus, but during postnatal life this regulating role of NO seems less prominent. It is therefore possible that under conditions when arterial oxygen content is at postnatal levels NO exerts no action on smooth muscle. We therefore examined the impact of NO on cerebral blood flow and vascular resistance in five near-term lamb fetuses during intrauterine ventilation and oxygenation. Four additional fetuses were pretreated with indomethacin to investigate a posible additional regulatory role of prostaglandins on cerebral vascular resistance. Cerebral blood flow(Qbrain) was measured using radionuclide-labeled microspheres. A tracheal tube was inserted to ventilate the fetus. After recovery, Qbrain and resistance in the cerebral vascular bed(Rcer) were measured during the following subsequent conditions: before and after increasing fetal arterial O2 content by ventilation with air, after inhibition of NO production with Nω-nitro-L-arginine during and after cessation of ventilation, and finally after infusion of L-arginine to increase nitric oxide production. Ventilation decreased Qbrain (95 ± 18 to 47 ± 15 mL/100 g/min) and increased Rcer.Nω-Nitro-L-arginine did not alter Qbrain (52 ± 13 mL/100 g/min) or Rcer during ventilation and oxygenation, indicating no modulating role of NO during higher arterial oxygen content. On cessation of ventilation, Po2 returned to fetal levels and Qbrain increased significantly, but did not return to baseline fetal values (83 ± 7 mL/min). Infusion of L-arginine increased Qbrain to baseline fetal levels (116± 30 mL/min). However, indomethacin pretreatment prevented the rise in cerebral blood flow after cessation of ventilation and after additional L-arginine infusion (Qbrain, 53 ± 20 and 52 ± 4 mL/100 g/min, respectively). These studies indicate that, during postnatal levels of arterial oxygen content, NO does not exert an action on smooth muscle cells of the cerebral resistance vessels as it does at lower arterial(fetal) oxygen content. They further show that prostaglandins are important in facilitating the full expression of NO-induced vasodilation.
Keynote speaker 1: Computational electromagnetics: Past, present, and future

Electromagnetics and Maxwell's equations have been instrumental in the conception of many electrical engineering technologies. It the beginning, it was telegraphy, and rotating machineries. Over the years, electromagnetics has given rise to numerous technologies like wireless communications, antennas, radar, and masers. On the optics side, simplified ray optics theory was used to design lenses and focusing systems. As many optical systems can be described by ray optics approximations, the first area that requires the full solution of Maxwell's equations is in microwave engineering, antenna design, and remote and subsurface sensing. Hence, there were pressing needs to design better antenna systems for communication, radar for target identification, and radio waves for remote sensing. While closed form solutions offered some physics insight, approximate solutions were invoked to further expand the insight of designers and engineers. When approximation solutions were exhausted, numerical methods or computational electromagnetics (CEM) were developed to further aid designers and engineers. As demand for numerical methods looms, fast and efficient methods of solving Maxwell's equations become a popular topic of research. There are essentially two classes of solvers for Maxwell's equations: differential equation solvers and integral equation solvers. While differential equation solvers use more unknowns than integral equation solvers, they are easy to implement and to maintain. Integral equation solvers, on the other hand, use fewer unknowns, but are more difficult to implement. They also yield dense matrix systems that are expensive to solve and store. However, the advent of fast solvers has greatly expedited their solution efficiency. As of this point, dense matrix systems with over three billion unknowns have been solved using fast solvers. Also, the path to large scale computing requires the use of iterative solvers. Over time, as the demand for CEM solvers grows, more complex structures with a disproportionate number of unknowns need to be solved. They give rise to ill-conditioned matrix systems. Hence, preconditi oners or domain decomposition methods are designed to reduce the ill conditioning of matrix system. The preconditioners will greatly expedite iterative solutions to these problems. Maxwell's equations are also intimately related to mathematical geometry and to quantum physics. Differential geometry concepts can be invoked to help in the selection of basis and testing functions in finding the matrix representations of Maxwell operators. Furthermore, even when quantum theory is invoked in the quantization of electromagnetic fields, the fields are still governed by Maxwell's equations. Therefore, solutions of Maxwell's equations are needed even in the quantum regime. Since photons play an important role in the manipulation of quantum information, the solutions of Maxwell's equations will be instrumental even in quantum optics or quantum electromagnetics. They will play an important role in the area of quantum computers and quantum information.
Effect of retained austenite on the yielding and deformation behavior of a dual phase steel

Abstract Tensile tests were conducted on a vanadium containing dual phase steel at temperatures between −53 and + 187°C to determine the effect of retained austenite stability on tensile properties. The transformation of retained austenite to martensite with stress/strain was shown to be a contributing factor in the yielding and strain hardening behavior of the dual phase steel. Increasing the stability of the austenite, by increasing the test temperature, caused the expected shift in the austenite to martensite strain transformation to higher strains. This led to a lower initial strain hardening exponent which increased with strain, compared to the ambient and sub-zero temperature deformation where the initial strain hardening exponent was higher but decreased with strain. The former behavior, which accentuated the strain hardening ability at higher strains, led to an increase in the uniform and total elongations, suggesting that the ductility of dual phase steels can be further improved by optimizing the stability of the retained austenite.
The dynamical nature of enzymatic catalysis.

ConspectusAs is well-known, enzymes are proteins designed to accelerate specific life essential chemical reactions by many orders of magnitude. A folded protein is a highly dynamical entity, best described as a hierarchy or ensemble of interconverting conformations on all time scales from femtoseconds to minutes. We are just beginning to learn what role these dynamics play in the mechanism of chemical catalysis by enzymes due to extraordinary difficulties in characterizing the conformational space, that is, the energy landscape, of a folded protein. It seems clear now that their role is crucially important. Here we discuss approaches, based on vibrational spectroscopies of various sorts, that can reveal the energy landscape of an enzyme–substrate (Michaelis) complex and decipher which part of the typically very complicated landscape is relevant to catalysis. Vibrational spectroscopy is quite sensitive to small changes in bond order and bond length, with a resolution of 0.01 A or less. It is this sensitivi...
The control network of Iapetus

A control network of the Saturnian satellite Iapetus has been established photogrammetrically from pictures taken by the two Voyager spacecraft. Coordinates of 62 control points have been computed and listed; pixel measurements of these points were made on 14 Voyager 1 and 66 Voyager 2 pictures. Some of these points are identified on the preliminary U.S. Geological Survey map of Iapetus and many are identified by name. The Voyager 1 and Voyager 2 pictures covered limited regions of the satellite's surface and contained no overlapping areas. The longitude system on Iapetus is defined by the crater Almeric; the 276 deg meridian passes through the center of this crater. The obliquity of Iapetus has been measured as 0.4 deg + or - 1.6 deg. The mean radius of Iapetus has been determined at 718 + or - 8 km.
The rise, fall and resurrection of group selection

The changing fate of group selection theory illustrates nicely the importance of studying the history of science. It was Charles Darwin that first used something like group selection to explain how natural selection could give rise to altruistic behavior and moral instinct. These instincts could be accommodated by his theory of evolution, he argued, if they had evolved ‘for the good of the community’. By the 1960s, group selection had a new and vocal advocate in V.C. Wynne-Edwards. But this gave critics of the theory that selection might act on groups, rather than at the level of individuals or genes, a definable target, and from the mid-1960s to the 1980s group selection was considered the archetypal example of flawed evolutionary thinking. However, at the end of the 20th century ideas of group selection re-emerged as an important component of a multilevel theory of evolution.
Reaktionen von Alkylmetallverbindungen der Metalle der Gruppe III in der Gasphase, 111) Homogene Cycloisomerisierung von 1,4- und 1,5-Dienen katalysiert durch gasförmiges Trialkylaluminium†

Diolefine mit einer oder zwei Methylengruppen zwischen den Doppelbindungen konnen in der Gasphase in Anwesenheit katalytischer Mengen von geeignetem, gasformigem Trialkylaluminium nahezu quantitativ in die entsprechenden Methylencyclopentan- und sekundar in die Methylcyclopentenderivate isomerisiert werden. Die Versuche wurden im Temperaturbereich 150–250°C in Reaktionsgefasen mit inaktivem Oberflachenbelag („Teflon”) durchgefuhrt. Bei den gewahlten experimentellen Bedingungen scheint die Reaktion pseudo-unimolekular und weitgehend homogen zwischen den freien Molekulen in der Gasphase zu verlaufen. Der Reaktionsmechanismus wird besprochen. Reactions of Alkylmetal Compounds of Metals of Group III in the Gas Phase, 111). —Homogeneous Cycloisomerization of 1,4- and 1,5-Dienes Catalyzed by Gaseous Trialkylaluminium) In the gas phase and in presence of catalytic quantities of trialkylaluminium diolefins having the double bonds separated by one or two methylene groups undergo nearly quantitative cyclization to methylenecyclopentane and in a second step to methylcyclopentene derivatives. Experiments were carried out in the temperature range 150 to 250°C in „Teflon”-coated reaction vessels. Unter the experimental conditions given, the reaction appears to be largely homogeneous in nature and follows pseudounimolecular kinetics. The reaction mechanism is discussed.
Institutions and Caribbean Economic Performance: Insights from Jamaica

We explore the impact of social institutions on economic performance in Jamaica through a reinterpretation of the plantation economic model. In its original form, the plantation model fails to develop a causal link between the plantation legacy and persistent underdevelopment. Despite its marginalization, the model remains useful for discussions on growth and development. Consequently, we offer a reappraisal using the causal insights from Kenneth Sokoloff and Stanley Engerman. We use two examples to demonstrate how inequality encourages the formation of institutions that are inconsistent with growth, and an empirical analysis to confirm the hypothesized relationship between inequality, institutions, and economic development. Since inequality is expected to influence growth indirectly, we use a structural specification, which follows William Easterly’s recent test of Sokoloff and Engerman’s argument. Our reliance on a time-series specification is unique. We demonstrate that the expectation that, on average, inequality and growth is negatively related and that institutions may compromise growth are accurate for Jamaica, the most cited Caribbean nation in the current discourse. Our results carry several policy implications, including support for the recent calls in Jamaica for political restructuring. However, both the paucity of similar studies and the importance of the implications for sustainable growth and development demand further analyses.
Effect of Attire on Obtaining Directions

120 middle-aged women gave more detailed directions or additional helpful suggestions and were more willing to respond to a college-age female requesting directions when the latter was dressed conventionally rather than as a “hippie.” The data are consistent with the assumption that attire mediates perception of similarity and thus influences helping behavior.
Factors influencing the germination of seeds of the potato

1. The percentage and velocity of germination of potato seeds was more satisfactory when planted 1/8-inch deep than when planted at a greater depth. 2. No significant differences were obtained between covering the seeds with soil, or with 50 per cent soil and 50 per cent sand, or with sand. 3. High temperatures reduced the percentage and velocity of germination. 4. Alternating the temperature between 20° and 30° was more satisfactory than a constant temperature of 25°. 5. A higher velocity of germination was obtained when the seeds and seed-ball debris were allowed to ferment before washing and drying. 6. Soaking the seed in an aqueous solution of potassium nitrate did not affect the percentage or the rate of germination.
Multilevel control of extracellular sucrose metabolism in Streptococcus salivarius by sucrose.

Summary: Standardized experimental conditions were established to test the role of sucrose in the regulation and control of its metabolism in Streptococcus salivarius. A fresh isolate of S. salivarius was used. The extracellular dextranase activity of cells grown on sucrose was 10-fold higher than that of cells grown on glucose, fructose or galactose. This activity increased in less than 5 min following the addition of sucrose to galactose-grown cells, a phenomenon which was affected by neither rifampicin nor chloramphenicol which inhibit transcription and translation, respectively. Extracellular fructanase activity was 2-fold higher when cells were grown on sucrose than when they were grown on the other sugars. This increase also occurred within 5 min, but was diminished by transcriptional and translational inhibitors. De novo synthesis was required for the production of extracellular glucosyltransferase (GTF) activity which, upon the addition of sucrose, became associated with the cell surface. Conversely, cell-associated fructosyltransferase (FTF) activity appeared to require genetic induction for its production and cell-surface association, but required sucrose for its release from the surface framework. Versatility in the control mechanisms of this complex set of enzymes allows their expression and function to be regulated at several widely separated stages in the life histories of these proteins.
Effect of a dental air turbine drill on the bacterial counts in air

Abstract The results of this study demonstrate that large numbers of microorganisms are liberated into the surrounding air when an air turbine drill is used for excavating procedures. The ejected contaminated water droplets, liberated into the air by the air propellent, cause a significant percentage increase in the number of organisms per cubic foot per minute of sampled air. Many of these contaminated particles bear a physical resemblance to a “droplet nucleus,” since they remain suspended for periods of up to 30 min. in the air. Further studies using longer-timed blood agar plates may show that these organism-bearing particles remain suspended in air for even longer periods of time. The dental profession should direct efforts towards eliminating this hazard, since it is possible to inhale highly pathogenic organisms while operaing on patients with communicable diseases.
Noninterferometric optical subtraction using reflection-electroabsorption modulators.

A noninterferometric technique for optical subtraction is demonstrated that employs a multiple-quantum-well reflection–electroabsorption modulator and provides lower insertion loss, larger contrast ratio, and linearity over a larger dynamic range than similar techniques previously reported.
Modulation of Progesterone Synthesis and Cytochrome P450 Levels in Rat Luteal Cells during Human Chorionic Gonadotropin-Induced Desensitized State*

Down-regulation of hCG receptors and a steroidogenic lesion in progesterone production were observed in isolated luteal cells after 24-h treatment of pseudopregnant rats with 50 IU hCG. The luteal cells from hCG-desensitized rats exhibited a complete loss of steroidogenic response to lipoproteins in both the absence and presence of hCG. This loss of response was not overcome by the addition of 25-hydroxycholesterol. To examine if the loss of steroidogenic response is due to a transient loss of steroidogenic enzymes or inadequate delivery of substrate cholesterol, cholesterol side-chain cleavage enzyme (P4508cc) activity was measured in the isolated mitochondria. No differences appeared in enzyme activity between control and hCG-treated groups. Furthermore, electron paramagnetic resonance spectra of mitochondrial cytochrome P4508cC from control and hCG-treated groups exhibited no appreciable differences in low spin electron paramagnetic resonance signal (g = 1.9, 2.2, and 2.4) or high spin EPR signal (g = ...
Microstructural pathways for the densification of slip cast alumina

Abstract The effect of slip casting condition and hence particle packing on densification and microstructural evolution was evaluated during isothermal sintering of a commercial alumina powder at 1350 °C. While there was significant effect of flocculation on solid volume fraction at short sintering times there appeared to be no inherent barrier to the eventual attainment of the same limiting solid volume fraction. Microstructural pathways based on average microstructural parameters and microstructural populations revealed no effect of casting condition on grain-scale pathways at this temperature. It is thought that microstructural pathways at higher length scales based on grain clusters will reveal the effect of slip casting independent of grain coarsening behavior.
Oral language skills of children with defective articulation.

Oral language achievement was studied in 100 matched subjects, half with defective articulation and half with normal speech. The following language scores were derived from the language samples: me...
Parenting, autonomy and self-care of adolescents with Type 1 diabetes.

In the United States T1DM is the predominant type of diabetes in youth, affecting about 1 in every 400-600 youth (National Institute of Diabetes and Digestive Diseases, 2005). During adolescence diabetes control worsens and disease management self-care behaviors decline ( Urbach et al, 2005; Pasquier-Fediaevsky, Chwalow, the PEDIAB Collaborative Group, & Tubian-Rufi, 2005); this contributes to long term diabetes complications (Silverstein, et al., 2005), and evokes fear and anxiety in parents (Gonder-Frederick et al., 2006; Streisand, et al. 2005). Further, T1DM is complex and demanding and must be integrated with the adolescents' quest for greater autonomy. Parents' concerns and fears about the teen's diabetes self-management abilities during this time can heighten parental attachment behavior and affect the parents' ability to support autonomy development necessary for effective self-care. In this study, we test an attachment model of adolescent cognitive autonomy development in T1DM. We examine maternal processes that can be heightened through strong activation of maternal attachment to assess their influence on autonomy and self-care. These processes include maternal separation anxiety, mother-adolescent conflict, and maternal behaviors in interaction with the adolescent. Maternal parenting processes may be especially important for those adolescents who have T1DM as mothers have responsibility for one-third of the diabetes management task for early adolescents (Drotar & Ievers, 1994), while fathers have responsibility on the average for less than one task (Dashiff, 2003).
Characterization by capillary electrophoresis of the surface glycoproteins of ovine lentiviruses before and after treatment with glycosidic enzymes

Ovine lentiviruses are a group of viruses that infect sheep and goats. These viruses contain a surface glycoprotein (SU) that is very similar among the viral strains. Sera from infected animals react equally well with SU from each strain. Monoclonal antibodies produced to SU can distinguish among some of the viral strains. In order to delineate these differences we treated SU from several viral strains with the glycosidic enzymes. These enzymes included a mixture of exoglycosidases, beta-N-acetyl glucosaminidase, neuraminidase and endoglycosidases D, F and H. After these treatments we observed changes in the reactivities of the monoclonal antibodies that were directed to SU. In order to characterize these changes on the surface epitopes, SU from the different viral strains were subjected to free zone capillary electrophoresis (CZE) using an 0.02 M phosphate buffer at pH 9.0 at a running voltage of 5 kV. Differences were readily seen between SU that had not been treated and SU that had been treated with the glycosidic enzymes. Each viral strain had a characteristic electropherogram. The electropherograms indicated that the heterogeneity of the charge on SU was increased after the enzyme treatments. From these results we have concluded that the carbohydrate moieties play an important role in contributing to the surface charge of SU. This charge affects the nature of its surface epitopes and has an impact on its biological function.
A spatial non-dynamic LQG controller: Part II, theory

For part I see ibid., p.3326-32 (2004). Fundamental theory is derived for control of adaptive optics used in astronomical telescopes, and for possible other applications involving shape control, vibrations, and other spatial control problems in which the control system acts much faster than a fixed process, or the observable and controllable subspaces are both finite dimensional. The theory is developed from a feedforward rather than feedback viewpoint. The LQG separation into estimation followed by deterministic control is shown to hold even under non-dynamic and feedforward formulation. Then observable and controllable subspaces can be defined, which must hold for a fixed process even in the dynamic case. An example of a dynamic process (adaptive optics) is given in which observability and controllability can be used to reduce the state space to finite dimension. Corresponding costs are evaluated, and compared with any linear controller in both feedforward and feedback.
Intersectin-1s: an important regulator of cellular and molecular pathways in lung injury

AbstractAcute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe syndromes resulting from the diffuse damage of the pulmonary parenchyma. ALI and ARDS are induced by a plethora of local or systemic insults, leading to the activation of multiple pathways responsible for injury, resolution, and repair or scarring of the lungs. Despite the large efforts aimed at exploring the roles of different pathways in humans and animal models and the great strides made in understanding the pathogenesis of ALI/ARDS, the only viable treatment options are still dependent on ventilator and cardiovascular support. Investigation of the pathophysiological mechanisms responsible for initiation and resolution or advancement toward lung scarring in ALI/ARDS animal models led to a better understanding of the disease’s complexity and helped in elucidating the links between ALI and systemic multiorgan failure. Although animal models of ALI/ARDS have pointed out a variety of new ideas for study, there are sti...
Investigation of TRV across circuit-breaker of series compensated double-circuit UHV transmission lines

State Grid Corporation of China plans to build the Huainan-Wannan-Zhebei-Huxi UHV double-circuit transmission project and install series capacitors (SCs) in Huainan-Wannan transmission lines. During the circuit breakers clearing system faults on series compensated transmission line, the transient recovery voltage (TRV) of circuit breaker may be increased due to the impact of series capacitor. If there is no countermeasure, the TRV may higher than the limit in circuit breaker standard. This phenomenon may result in the failure of clearing system fault and the damage of circuit breaker. This paper investigated the influences of series capacitor on TRV. In order to limit the TRV, the fast bypass series capacitor based on system protection and relay system is suggested.
Cisplatin ototoxicity in developing gerbils.

Abstract This experimental study was undertaken to investigate the dose-related effect of cisplatin exposure in young gerbils (2 weeks of age) and explore the relationship between different methods used to monitor auditory function after exposure to cisplatin. Four groups of animals, including a control group, were used. The treatment groups, D1 ( n =6), D2 ( n =7) and D3 ( n =6), received one, two, and three doses of cisplatin (5 mg/kg/dose), respectively, at weekly intervals. Treated animals were first exposed to cisplatin at 2 weeks of age. Distortion product otoacoustic emissions (DPOAE) and auditory brainstem responses (ABR) were measured in treated and control animals at 6 weeks of age. The effects of dose and frequency on the DPOAE amplitude, as well as the relationship between the DPOAE and the ABR thresholds were analyzed. Animals in the D1 and D3 groups demonstrated significant elevation of DPOAE and ABR thresholds. Interestingly, animals in the D2 group demonstrated a bimodal distribution of DPOAE and ABR responses, with four animals severely affected and three not showing an effect. A tendency for a bimodal distribution of DPOAE and ABR responses was also observed in the D1 group, at frequencies below 8 kHz.
Principles of competitive exclusion for discrete populations with reproducing juveniles and adults

Abstract We invent notions of dominance and weak dominance for discrete multi-species systems with competing juveniles and adults. In this model, both the juveniles and adults are allowed to reproduce. We prove that, a dominant species drives the dominated species to extinction. In discrete juvenile-adult systems that do not allow juveniles to reproduce, it is known that weak dominance is equivalent to dominance, provided all the growth functions are exponentials. We show that if juveniles are allowed to reproduce, then a weakly dominant species could be driven to extinction. It all the growth functions are exponential functions, we obtain sufficient conditions that guarantee the equivalence of weak dominance and dominance.
Titanium tetrachloride: an unusual agent with the potential to create severe burns.

Titanium tetrachloride (TiCl 4 ), an intermediate compound in the production of white pigment, can cause severe burns. Two cases are reported in which TiCl 4 created 18% to 20% total body surface area burns. These full-thickness injuries were the combined consequence of hydrochloric acid and the heat that was generated in areas where this otherwise stable compound was mixed with perspiration. TiCl 4 combined with water is extremely dangerous, and its immediate treatment-towel drying before irrigation-makes it unique among chemicals. Our experience suggests that in most cases grafting will be required. These chemical burns were self-limited and had no notable Systemic sequelae, Wound biopsy specimens taken on postburn days 3 and 6 were subjected to immunostaining that showed that TiCl 4 did not retard wound healing. Exposure time to TiCl 4 vapor will determine the pulmonary and ophthalmologic involvement in each case. Clinical awareness of the propensity of TiCl 4 to react with water-even when that water is in the form of perspiration-is vital because prompt management can limit the extent of injury.
Implementing the National Arthritis Action Plan: new population-based approaches to increasing physical activity among people with arthritis.

For the past 2 decades, community-based, person-focused intervention programs have provided opportunities for people with arthritis to increase their levels of physical activity, but true population-based approaches are just beginning to emerge. Although many authors appear to use the terms communityand population-based interchangeably, these terms actually reflect different dimensions of an intervention. Sharpe has provided a heuristic framework for conceptualizing community-based interventions (1). Community-based can be used to describe the setting or context of an intervention (the where of the intervention), whereas population-based can refer to the body of potential participants, which may be the entire population or a defined subgroup (the who of the intervention). As Sharpe described, community-based interventions may be population-based or more individually focused. Green and Kreuter clarify that a population-based approach must go beyond people who appear for treatment or turn out for an educational event (2). For the purpose of our discussion, we define a population-based intervention as one designed to reach out to most members of a defined population. Interest in population-based approaches for arthritis has been fueled by the publication of the National Arthritis Action Plan: A Public Health Strategy (NAAP), which catalyzed the public health system’s interest in arthritis and emphasized population-based approaches (3), and the recognition that person-focused, community-based programs, such as many of those reviewed by Boutaugh (4), are unlikely to reach large portions of the 70 million Americans with arthritis (5). Minor et al have shown that people with arthritis benefit from both structured exercise and the more broadly defined physical activity (which includes daily activities of moderate intensity such as walking, raking leaves, or washing the car); and person-focused, community-based programs have been developed by the Arthritis Foundation and others (6,7). However, little is know about effective population-based approaches to increase physical activity among persons with arthritis (PWA). The NAAP calls for the development of such population-based efforts (3). We will briefly review the NAAP and the Centers for Disease Control and Prevention (CDC) Arthritis Program that emerged from Congressional support of NAAP. We also will highlight physical activity initiatives being developed by the CDC and state health departments.
In Vitro Polymerization of a Functional Escherichia coli Amyloid Protein

Amyloid formation is characterized by the conversion of soluble proteins into biochemically and structurally distinct fibers. Although amyloid formation is traditionally associated with diseases such as Alzheimer disease, a number of biologically functional amyloids have recently been described. Curli are amyloid fibers produced by Escherichia coli that contribute to biofilm formation and other important physiological processes. We characterized the polymerization properties of the major curli subunit protein CsgA. CsgA polymerizes into an amyloid fiber in a sigmoidal kinetic fashion with a distinct lag, growth, and stationary phase. Adding sonicated preformed CsgA fibers to the polymerization reaction can significantly shorten the duration of the lag phase. We also demonstrate that the conversion of soluble CsgA into an insoluble fiber involves the transient formation of an intermediate similar to that characterized for several disease-associated amyloids. The CsgA core amyloid domain can be divided into five repeating units that share sequence and structural hallmarks. We show that peptides representing three of these repeating units are amyloidogenic in vitro. Although the defining characteristics of CsgA polymerization appear conserved with disease-associated amyloids, these proteins evolved in diverse systems and for different purposes. Therefore, amyloidogenesis appears to be an innate protein folding pathway that can be capitalized on to fulfill normal physiological tasks.