cssi/SciSciGPT-SciSciNet huggingface dataset:
The foraging ecology of the Gulf of Mexico stone crab Menippe adina (Williams et Felder)

Abstract Laboratory experiments were used to study prey species and size selection by the Gulf of Mexico stone crab Menippe adina (Williams et Felder) on oysters, i.e., Crassostrea virginica Gmelin and southern oyster drills Stramonita (Thais) haemastoma Grey. Stone crabs select smaller rather than larger oyster drills, and smaller rather than larger oysters. Two results support the idea that size selection in this crab is more the result of mechanical limitations to feeding on large prey than active choice for smaller prey. First, differences in size selection disappear when feeding rates are weighted by differences in handling times, which increase with prey size. Second, an estimate of prey value (tissue dry mass divided by handling time) does not differ dramatically with prey type or size, suggesting large variations in handling time obscure differences in prey energy content. Stone crabs select small oysters over small oyster drills. Stone crabs attack larger oyster drills more frequently than small oyster drills, and persist longer before rejecting them as prey. Neither attack frequency nor persistence increase significantly with increasing oyster size. We also studied aggressive interactions between stone crabs provided with oysters as prey and found that larger stone crabs had greater feeding rates than smaller crabs, and exhibited higher frequencies of dominant behaviors. Our results suggest that the relative importance of active choice vs. mechanical limitations in determining prey selection varies with the specific crab predator-prey system. Gulf of Mexico stone crabs may also affect oyster and oyster drill populations by selectively removing smaller individuals. Finally, smaller stone crabs may be forced to forage in suboptimal habitats, or at suboptimal times, by larger, more aggressive conspecifics.
Tradition and Change in the Chinese Business Enterprise

Until the recent emergence of a thriving economy along the China coast and among communities of Chinese diaspora all over the Pacific Rim, the history of Chinese business and entrepreneurship had received scant scholarly attention. The new interest, however, has also generated a great deal of confusing interpretations because so many of the successful Chinese business organizations and practices in contemporary East Asia do not seem to conform to Western or Japanese models. Moreover, Chinese traditional business ideology and institutions are often considered unprogressively clannish, lacking in the transformative power of entrepreneurship as well as in the spirit of communal trust. This contrasts rather sharply with the state of the field of business history in the United States, where it is far more developed and recognized. Thus, the history of the rise of large-scale, multi-unit, and professionally managed corporations from modest beginnings, as well as their crucial impact on the American economy, are...
Probabilistic Borda rule voting

An alternative voting system, referred to as probabilistic Borda rule, is developed and analyzed. The winning alternative under this system is chosen by lottery where the weights are determined from each alternative’s Borda score relative to all Borda points possible. Advantages of the lottery include the elimination of strategic voting on the set of alternatives under consideration and breaking the tyranny of majority coalitions. Disadvantages include an increased incentive for strategic introduction of new alternatives to alter the lottery weights, and the possible selection of a Condorcet loser. Normative axiomatic properties of the system are also considered. It is shown this system satisfies the axiomatic properties of the standard Borda procedure in a probabilistic fashion.
Marked medium effects on the substitution and the additionrearrangement-ejection reactions of (halomethyl) silanes with methoxides

Abstract Reactions of methoxides with (halomethyl)silanes at silicon are facilitated by aprotic solvents and cation separation.
Oxalate, calcium uptake and ATPase activity of sarcoplasmic reticulum vesicles.

Ca++-uptake and Mg++-Ca++-dependent ATPase activity of skeletal muscle sarcoplasmic reticulum vesicles were reciprocally affected by increasing the oxalate concentration from 0 to 4 mM. At 0-0:1 mM oxalate approximately 17% of the calcium was removed by the vesicles from the medium while the ATPase activity was maximal (∼0.66 μmoles Pi mg−1 protein min−1). Between 0.1 to 0.2 mM oxalate the ATPase activity was reduced to one-fifth but the uptake rose sharply and 100% of the 45Ca++ was removed from the medium. The uptake was maintained at this level at oxalate concentrations /gt0.4 mM but the ATPase activity remained inhibited. The kinetics of Ca++-uptake and ATPase activity were also differentially affected by oxalate. In the presence of oxalate, ruthenium red had only a very slight inhibitory effect on the calcium uptake. Addition of 0.1 mM EGTA removed 80% of the Ca++ from preloaded vesicles within 10 min. The formation of insoluble Ca-oxalate salt on the surface of the vesicle is suggested by these results. Calculations based on the Ksp of the calcium oxalate salt are presented to show its formation and the possible speciation of a Ca-oxalate complex which may affect the Ca++-uptake and ATPase activity.
Constriction of canine coronary arteries by platelet activating factor after brief ischemia

Abstract Platelet activating factor (PAF) has been suggested as a mediator of coronary spasm and acute myocardial ischemia. However, PAF can have either vasodilator or vasoconstrictor activities according to various reports. Because of the importance of endothelium in regulating vascular tone, we hypothesized that changes in endothelial function could modulate some of the observed differences in the activities of PAF. To test this hypothesis, PAF was infused directly into the left anterior descending coronary artery (LAD) of dogs at a rate of 0.3 μg/min before and after 20 min of LAD ligation followed by reperfusion. Coronary blood flow (CBF) was measured continuously via a Doppler flow probe. Likewise, responses to the endothelium dependent vasodilator, acetylcholine (ACh) were measured before and after the LAD ligation. Before ligation, PAF produced a vasodilatory response in the LAD, resulting in 28.4±11.0% increase in CBF and a 21.5±5.8% decrease in coronary vascular resistance (CVR). However, after ligation and subsequent reperfusion, 0.3 μg/min PAF produced vasoconstriction, resulting in a 10.2±8.7% decrease in CBF (p
Craft Unions and Minorities: Determinants of Change in Admission Practices

Race-based exclusionary practices of craft unions were the focus of intense political protest and legal action in the late 1960s and early 1970s. Previous research suggests that these pressures were followed by higher rates of minority entry into both apprentice programs and the trades themselves, but these analyses have not controlled for applicants' human capital characteristics nor for changing labor market conditions. In this paper, I analyze the success of minority and white applicants to a large craft union apprentice program before, during, and after a period of intense political conflict over discriminatory admission practices. I evaluate the predictions of the monopoly (bargaining power) model of discrimination, while controlling for variables relevant to human capital and split labor market (institutional) explanations. The results generally support the monopoly model explanation of the bases of change in discriminatory practices, while also indicating the importance of business cycle, human capital, and institutional processes in unionized construction labor markets.
DF analysis of NLSY IQ/achievement data: Nonshared environmental influences

Abstract DeFries and Fulker (1985) proposed DF analysis to measure genetic and shared environmental variance in kinship data. We use an adaption of DF analysis that can simultaneously account for genetic, shared environmental, and nonshared environmental influences within the same model. We fit this model to achievement measures from 5- to 12-year-old children from the National Longitudinal Survey of Youth (NLSY). The NLSY is a large national sample containing information to link kinship pairs at multiple levels, including cousins, half-siblings, and twins. One thousand forty-four pairs were identified by a kinship-linking algorithm. From five specific measures of intellectual ability we estimated median heritability of h 2 = .50 and shared environmental variance of c 2 = .16. We then tested for the presence of several specific nonshared influences. As predicted, differences between two related children in the number of books owned were related to differences in reading recognition scores, and trips to the museum were related to a measure of mathematical ability. A general measure of the home environment accounted for nonshared environmental variance in several specific measures of intelligence and in a general measure of cognitive ability.
Photoemission studies of the electronic structure of III–V semiconductor surfaces

Abstract The photoemission technique using synchroton radiation in the photon energy range 5–450 eV has been applied to the study of the electronic structure of some III–V semiconductor surfaces, prepared by cleavage in situ under ultrahigh vacuum conditions, ≲ 10 −11 Torr. For p-type GaAs(110), the Fermi level is pinned at the top of the valence band and thus no filled surface states extend into the band-gap. The situation is more complicated for n-type GaAs(110), where band bending easily can be introduced by extrinsic effects (impurities, cleavage quality, etc.) and push the Fermi level down to about midgap. Chemical shifts of inner core levels (3d for Ga and As) are used to obtain information on the bonding site of oxygen on the (110) surface. GaAs(110) can be exposed to atmospheric pressure of molecular oxygen without breaking the bonds between the surface atoms and the bulk. Oxygen is predominantly bonded to the As atoms on the surface. The oxidation behavior is strikingly different for GaSb(110) with formation of gallium and antimony oxides on the surface directly upon oxygen exposure. Heavier oxidation of GaAs(110) and breaking of the surface bonds will also be reported.
NIS interpretations: Race and the National Incidence Studies of Child Abuse and Neglect

Abstract The National Incidence Studies (NIS) of Child Abuse and Neglect are the primary estimates of actual child maltreatment rates in the United States. Findings from the NIS-2 of 1986, and the NIS-3, of 1993, have been presented as demonstrating that Blacks and Whites are maltreated at equal rates. The NIS-4, using 2006 data, was presented as showing markedly different findings from the prior NIS studies with regard to race. A supplementary NIS-4 report on race argued that differences between the NIS-3 and NIS-4 were due to better precision and an expanding income gap between Blacks and Whites between 1993 and 2006. This paper will demonstrate that the NIS-2 and NIS-3 did not, as is commonly believed, show equivalence between Black and White maltreatment rates and that the NIS-2, NIS-3 and NIS-4 do not differ markedly in their racial findings. Further, the large historical increase in the Black/White income gap cited in the NIS-4 race supplement derives from a simple failure to account for inflation. If left unaddressed, misinterpretations of NIS data will continue to misinform policy, cloud the issue of racial bias in the child welfare system and obscure the ongoing role of concentrated poverty in driving racial disproportionality.
The management of ovarian-cancer-caused bowel obstruction

Abstract The records of 518 patients with ovarian cancer between 1969 and 1977 were retrospectively analyzed. During the course of their disease, 127 patients developed intestinal obstruction. Obstructions occurred in 17 (13.9%) of stage I patients, 17 (16.8%) of stage II patients, 72 (30.0%) of stage III patients, 20 (36.4%) of stage IV patients, and in 1 of the 3 patients whose initial staging was unknown. At advanced stages, patients developed intestinal obstruction more quickly. Patients deemed terminal and thus inoperable survived an average of 2 months. Those treated surgically for these obstructions survived an average of 7 months. Colostomy patients lived for 6.6 months. The degree of obstruction, partial or complete, was not significantly related to survival. The median time of survival for all patients with obstruction was 112 days.
Functional and pathological significance of phospholipid asymmetry in erythrocyte membranes

The normal asymmetric distribution of phospholipids in the plasma membrane is perturbed in erythrocytes from patients with chronic myelogenous leukemia. Since experimentally-produced lipid-symmetric erythrocytes are more interactive with cells of the reticuloendothelial system than are their lipid-asymmetric counterparts, the biological recognition of chronic myelogenous leukemia erythrocytes by the reticuloendothelial system was examined. With one exception, all erythrocyte samples from patients with chronic/benign chronic myelogenous leukemia were more adherent to endothelial cells and more readily phagocytosed by macrophagesin vitro than were normal erythrocytes. Thus, these naturally occurring pathological erythrocytes display the same dysfunctional intercellular interactions as the laboratory models.
Cancer cells’ epigenetic composition and predisposition to histone deacetylase inhibitor sensitization

Normal cells are up to ten times more resistant to histone deacetylase inhibitors (HDACis)-induced cell death compared with transformed cells. The molecular processes underlying this selectivity for cancer cells are still not well understood. Although a differential response to oxidative stress and capacity to repair damaged DNA have been described in some systems, these cannot fully account for the sensitivity of cancer cells to HDACis since the heterogeneity of cancer cells prompts differential sensitivities to reactive oxygen species and generates a panoply of defective DNA repair mechanisms within given histologies, cancer cell lines and tumor xenografts. It seems also unlikely that the influence of HDACis on cancer treatments reside primarily on gene transcription, since gene-expression profiling aimed at defining correlation with response to HDACis in cancer cells indicates that less than 5% to approximately 20% of transcribed genes are altered by HDACis treatment. Moreover, the altered genes vary from cell line to cell line and between different HDACis. Therefore, no consistent picture of a target(s) or pathway(s) modulated by HDACis has emerged. One consistent parameter that has however been observed in peripheral blood mononuclear cells of patients treated with HDACi is the accumulation of acetylated histones. Because one of the primary functions of histone acetylation is to increase chromatin accessibility, this article will explore the possibility that intrinsic molecular and structural characteristics of cancer cells provide a selective advantage for HDACis sensitivity.
Staging laparoscopy in the management of intra-abdominal malignancies.

Abstract Background: Laparoscopy in the evaluation of intra-abdominal malignancies has become a debated issue. Proponents have claimed that it increases resectability rates, whereas opponents suggest that many patients require laparotomy regardless of the laparoscopic findings. The purpose of this study was to compare outcomes in patients undergoing staging laparoscopy versus those who were managed by initial exploratory laparotomy. Methods: The medical records of all patients during an 18-month period who underwent surgical evaluation for upper gastrointestinal or hepatobiliary malignancies were reviewed. Forty-eight patients underwent staging laparoscopy (SL) initially; 80 patients underwent initial exploratory laparotomy (EL). Data obtained included type of cancer, laparoscopic findings, laparoscopic determination of resectability, laparoscopic procedures, open determination of resectability, open procedures, and length of stay (LOS). Statistical analysis was done by using Fisher exact test or the Mann-Whitney U test. Results: The malignancies of 75% of patients were deemed resectable by SL. Of these, 77.8% were resected. This compares to 56.3% resectability rate in the EL group (P =.025). SL findings in patients with unresectable malignancies were carcinomatosis (75%), liver metastasis (33.3%), and direct invasion (16.7%). In the 8 false-negative SLs, 75% were unresectable as a result of vascular invasion and 25% for other reasons. Findings in the EL group whose malignancies were unresectable were carcinomatosis (34.3%), direct invasion (22.6%), liver metastasis (42.9%), and vascular invasion only (17.1%). Therefore 82.9% of patients in the EL group could have been determined to have unresectable malignancy by SL. In the EL group 22.5% of the laparotomies were nontherapeutic, whereas 4.2% of patients in the SL group underwent nontherapeutic laparotomy. Average LOS for unresectable patients in the SL group was 0.5 days, with 75% discharged the same day of operation. This compares to 10.9 days in the EL group (P
Infants' understanding of numerical transformations

This research explored infants' understanding of transformations that change the numerosity of a set. Do infants know how the insertion or deletion of a single object affects the relative numerosity of two sets? Four age groups (14-, 18-, 24- and 28-month-olds) were tested on problems involving sets whose numerosities were never greater than 2. The children were encouraged to find the set with more objects, after watching the experimenter cover up two sets and then transform one of them by performing either an insertion or a deletion. On the start-equal problems, the two sets had the same number of objects until the transformation was performed, so that when an object was inserted the transformed set always had more and when an object was deleted the untransformed set always had more. On the start-unequal problems, the initial numerosities of the two sets were varied so that these relations between the type of transformation that was performed and the relative numerosities of the two sets no longer held. One set initially had two objects in it and the other set had none. Insertions were performed on the smaller set, so that it still had less than the untransformed set; and deletions were performed on the larger set, so that it still had more than the untransformed set. Performance improved significantly across the four ages tested. However, every age group showed some understanding of the transformations. These results add to the growing body of evidence for an understanding of numerical relationships in infancy.
TH‐C‐350‐03: A Dosimetric Validation of RapidArc Treatment Plans for 5 Treatment Sites

Purpose: To compare calculated and delivered dose distributions from RapidArc™ (a form of volumetric modulated arc therapy, Varian Medical Systems). RapidArc is a novel approach for delivering single arc therapy in less than 2 minutes, while achieving dose distributions comparable to current IMRT. We report the first detailed dosimetric validation for 5 different tumour sites with RapidArc plans. Method and Materials: Clinical RapidArc plans were generated with a pre‐clinical version for single cases with glioblastoma multiforme, multiple brain metastases, nasopharynx‐, oropharynx‐ and pancreas carcinoma. All five plans were delivered with a Varian Linac and measured in a solid water phantom for 5 coronal planes, 2 cm separated, using double Gafchromic®EBT films. Plans were also measured using ionisation chamber arrays (MatriXX). Measured and calculated dose distributions were compared using 2D gamma evaluation with limits of 2mm and 3.5% (of typical PTV dose in phantom). Results: All 25 film measurements showed high agreement with calculations, with a mean gamma of 0.29 and on average 1% (maximum 3%) of the film surface exceeding a gamma of 1.0. Relatively strong spatial dose modulations could be measured, within 95–107% dose range in the PTV, which were not completely predicted by calculations. This could lead to local dose changes >3% when changing a plane by 2mm. MatriXX measurements corresponded better with dose calculations than film measurements, which may be due to the limited resolution of 7.6mm of MatriXX. Conclusion: RapidArc accurately delivers the planned dose distributions. Film measurements may be preferred for dosimetric verification as more dose modulation is detectable than with ionisation array measurements. A “2.5D” gamma evaluation taking into account multiple adjacent dose planes would show better agreement for film dosimetry. Our results indicate that RapidArc can be introduced into clinical practice. Conflict of Interest: Research was a collaboration with Varian Medical Systems.
Counterdiffusion of p-xylene/benzene and p-xylene/o-xylene in silicalite studied by the zero-length column technique

This paper describes the extension of the zero-length column (ZLC) method of measuring intracrystalline diffusion to the study of counterdiffusion. Theoretical ZLC response curves are derived for two simple models considering chemical potential gradient as the driving force for transport with the intrinsic mobilities either constant or inversely dependent on total loading. Experimental response curves for benzene−p-xylene and p-xylene−benzene in silicalite are shown to be consistent with the first of these models. The response curves conform quantitatively to the response predicted from this model using the measured pure component diffusivities. However, the behavior of the benzene−o-xylene and p-xylene−o-xylene systems does not conform to the simple model. The retardation caused by o-xylene is substantially greater than that predicted from the single-component diffusivity data. A simple microdynamic explanation is suggested to account for this apparent anomaly.
Suspending Routine Duty The Sociological Significance of Military Holidays and Ceremonies

Recently, the sociologist Amitai Etzioni developed a theory of the significance of holidays as “seedbeds of virtue” and agents of socialization. With minor modifications, Etzioni’s theory can shed light on the sociological significance of holiday celebrations and ceremonies in military organizations. This article focuses on two key aspects of military holidays that distinguish them from their civilian counterparts: (1) the centrality of the normative notion of “duty” in military culture and (2) the unique temporal constraints to which military holiday celebrations are subjected. Consistent with Etzioni’s claim that holidays function, in part, as agents of socialization, the authors examine holiday celebrations and ceremonies at a major organizational site of military socialization, the United States Air Force Academy. The authors explain how unique properties of military organizations and cultures shape the nature and sociological functions of holiday celebrations and ceremonies in the armed forces.
Redox control of retinoic acid receptor activity: a novel mechanism for retinoic acid resistance in melanoma cells.

Retinoic acid (RA) slows growth and induces differentiation of tumor cells through activation of RA receptors (RARs). However, melanoma cell lines display highly variable responsiveness to RA, which is a poorly understood phenomenon. By using Northern and Western blot analyses, we show that RA-resistant A375 and RA-responsive S91 melanoma cells express comparable levels of major components of RAR-signaling pathways. However, A375 cells have substantially higher intracellular reactive oxygen species (ROS) levels than S91 cells. Lowering ROS levels in A375 cells through hypoxic culture conditions restores RAR-dependent trans-activity, which could be further enhanced by addition of the antioxidant N-acetyl-cysteine. Hypoxia also enhances RAR activity in the moderately RA-responsive C32 cells, which have intermediate ROS levels. Conversely, increasing oxidative stress in highly RA-responsive S91 and B16 cells, which have low ROS levels, by treatment with H2O2 impairs RAR activity. Consistent with these observ...
On the continued fraction representation of computable real numbers

Abstract The continued fraction representation of real numbers is compared with other types of representations of real numbers in the context of recursive analysis. The main result states that a modification of the natural continued fraction representation, based on the concept of principal convergents of real numbers, is polynomially equivalent to the left cut representation in the sense that, for any given real number x , the two representations of x are computable from each other in polynomial time. Following from earlier studies on the left cut representation of real numbers, this result verifies the intuition that there is no efficient algorithm for implementing addition of real numbers in the continued fraction form. On the other hand, when considering computable real functions, the continued fraction representation behaves differently from the left cut representation: a computable real function must be continuous if it is defined as a mapping on Cauchy sequences of real numbers; it must be left-continuous, but is not necessarily continuous, if defined as a mapping on left cuts; and it ist necessarily left- or right-continuous if defined as a mapping on continued fractions.
Temperature in rubber moldings during injection molding cycle : simulation and experimentation

Measurements of temperature traces in a rubber compound are carried out during injection molding cycle. The measurements are performed using a special temperature measuring device inserted into molds having a cylindrical cavity. The measurements indicate complex temperature traces with a minimum and a maximum during molding cycle. Calculations of tem perature field are performed based on the finite difference solution of the two- dimensional transient heat conduction equation with convective heat transfer on the boundary. The predicted temperature traces, although qualitative, cor rectly simulate experimental observations.
Ice stream basal conditions from block‐wise surface data inversion and simple regression models of ice stream flow: Application to Bindschadler Ice Stream

[1] Widespread basal conditions controlling ice stream flows are still beyond the scope of direct observation, thus knowledge of their magnitudes and variabilities comes from inversion of surface measurements: ice velocities, surface elevations, and thicknesses. We present a new approach to implement a widely accepted inverse method on regular (10 × 10 km) blocks, smaller than the whole domain, to enhance the spatial resolution of calculated basal conditions. Inverted basal friction coefficients and calculated shear stress have sharp transitions and large variations in small areas. Overall, the obtained basal shear stress is very small in regions of fast flowing ice. The results of the inversion, along with the surface variables, are used to construct two simple regression models of Bindschadler Ice Stream (former Ice Stream D) that reproduce 96% of observed velocity variations. While highly idealized, these regression models are sufficiently informative to be considered as parameterizations for ice stream flow in large-scale ice sheet models which lack the spatial and temporal resolution necessary to simulate ice stream dynamics in detail.
Characterization of laser-induced air plasmas and thin films using third harmonic generation microscopy

Third harmonic microscopy is applied to probe electron densities in femtosecond laser-induced air plasmas, determine nonlinear susceptibilities of thin films, and image nascent, laser incubated, and laser damaged dielectric coatings with unprecedented contrast. The relative contribution of signals from the layer of interest and its surroundings is analyzed.
The role of brand credibility in predicting consumers' behavioural intentions in luxury restaurants

This study investigates the impact of brand credibility on consumers' brand purchase intention via various constructs. This study focuses on luxury restaurant brands and luxury restaurant patrons. A structural equation model is presented. The significant and positive impact of brand credibility on brand preference, information cost saved, brand prestige was conformed as well as their positive impact on behavioural intention, which tends to validate the proposed research framework. Implications concerning both research and managerial practices are offered.
Resolution of Converging Replication Forks by RecQ and Topoisomerase III

RecQ-like DNA helicases pair with cognate topoisomerase III enzymes to function in the maintenance of genomic integrity in many organisms. These proteins play roles in stabilizing stalled replication forks, the S phase checkpoint response, and suppressing genetic crossovers, and their inactivation results in hyperrecombination, gross chromosomal rearrangements, chromosome segregation defects, and human disease. Biochemical activities associated with these enzymes include the ability to resolve double Holliday junctions, a process thought to lead to the suppression of crossover formation. Using Escherichia coli RecQ and topoisomerase III, we demonstrate a second activity for this pair of enzymes that could account for their role in maintaining genomic stability: resolution of converging replication forks. This resolution reaction is specific for the RecQ-topoisomerase III pair and is mediated by interaction of both of these enzymes with the single-stranded DNA-binding protein SSB.
The Effect of Propranolol on Uncontrolled Rage Outbursts in Children and Adolescents with Organic Brain Dysfunction

This paper reviews our experience using propranolol, a β -adrenergic blocking agent, in 30 patients who had uncontrolled rage outbursts over a period of at least 6 months, starting in childhood or adolescence. All of these patients had concomitant organic brain dysfunction, ranging from minimal brain dysfunction to severe, uncontrolled seizures. All patients had prior unsuccessful medication treatment, consisting of trials on stimulants, neuroleptics, anticonvulsants, or combinations of these. The majority of patients also had prior psychotherapeutic intervention, all without success. In our retrospective study, more than 75% of the patients demonstrated moderate to marked improvement in control of rage outbursts and aggressive behavior. These data point to the merits of a controlled prospective study of the use of propranolol in treating neurologically impaired children and adolescents with uncontrolled rage outbursts. Journal of the American Academy of Child Psychiatry , 21, 2:129–135, 1982.
Volumetric properties of a nonionic microemulsion

Abstract A model nonionic microemulsion system was studied by dilatometric methods as a function of temperature (15–30°C) and volume fraction of dispersed phase, W 2 (0.2–0.01). From these measurements the partial specific volume, v 2 , of the dispersed phase was derived, and the results were extrapolated to infinite dilution to give v 2 0 . It was found that v 2 was linear with W 2 ; no breaks were evident, indicating that the microemulsion is “dilutable.” A plot of v 2 0 against temperature was slightly concave down, indicating that the microemulsion surface was a water structure breaker, as expected for a polyethylene oxide covering. The excess volume V E and partial excess volume ∂ v E /∂W 2 were also determined. Since V E was significantly different from zero, ideal mixing did not hold. The partial excess volume extrapolated to infinite dilution was found to be about −0.042 ml g −1 , which is also comparable to that found for polyethylene oxide, about −0.048 g −1 . The volume decrease on mixing for the microemulsion with the (nominal) value of 0.10 was found to be about 40 × 10 −4 ml g −1 , indicating that the microemulsion composition is closer to a lower critical solution temperature.
Formation and ethene substrate reactions of iridium(II) porphyrin metal-centered dπ radicals

Monomeric iridium(II) porphyrin complexes of tetrakis(2,4,6-trialkylphenyl)porphyrin ligands that are generated by photolysis of the Ir–Me derivatives are found to have the dxy2 dz22 dxz,yz3 ground electron configuration which differs from the dxy2 dxz,yz4 dz21 configuration observed for the Co(II) and Rh(II) analogs; reactions of these Ir(II) species with ethene reflect both the metallo-radical reactivity and the varying steric demands for the series of porphyrin ligands.
Pretraining context effects: Training assignment as feedback.

This study examined the effects of framing training program assignments on training outcomes. A model was developed that suggests that the framing of training assignments can provide feedback regarding past performance and result in different attitudinal and motivational levels going into training. Participants were randomly assigned to 2 differently framed training programs (remedial vs. advanced). Attributions regarding past performance were found to interact with training assignments to affect pretraining selfefficacy. Both perceptions of past performance and expected assignment were found to moderate the relationship between training assignment and fairness perceptions. Also, motivation to learn was a key variable linking pretraining characteristics and training outcomes. Implications for training effectiveness research and practice are discussed
Impact of setup variability on incidental lung irradiation during tangential breast treatment

Purpose: This study aimed to determine the variability in treatment setup during a 5-week course of tangential breast treatment for patients immobilized in a customized hemibody cradle, to assess the relationship between the height of the lung shadow on the tangential port film and the percentage of lung volume irradiated, and to estimate the impact of setup variabilities on irradiated lung volume. Methods: One hundred seventy-two port films were reviewed from 20 patients who received tangential beam treatment for breast cancer. The height of the lung shadow at the central axis (CLD) on each port film was compared to the corresponding simulator film as an assessment of setup variability. A three-dimensional dose calculation was performed, and the percentage of total lung volume within the field was correlated with the CLD. The three-dimensional dose calculation was repeated for selected patients with the location of the treatment beams modified to reflect typical setup variations. Results: The CLD measured on the port films was within 3 mm of that prescribed on the simulator film in 43% (74 of 172) of the port films. The variation was 3-5 mm in 26%, 5-10 mm in 25%, and >10 mm in 6%. The height of the lung shadow correlated with the percentage of lung volume included in the radiation field (r 2 = 0.6). Typical variations in treatment setup resulted in ≤5fb fluctuation in the absolute volume of ipsilateral lung irradiated. Conclusion: The current immobilization system used in our clinic provides a clinically acceptable reproducibility of patient setup. The height of the lung shadow is reasonably well correlated with the percentage of irradiated lung volume. During a typical 5-week course of radiotherapy, the ipsilateral irradiated lung volume fluctuates <5%.
Alcohol consumption and HIV disease progression: are they related?

Background: The relationship between alcohol consumption and HIV disease progression has received limited attention in the era of highly active antiretroviral therapy (HAART). Methods: We assessed CD4 cell count, HIV RNA levels, and alcohol consumption in the past month, defined as none, moderate, and at risk, in 349 HIV-infected people with a history of alcohol problems. We investigated the relationship between alcohol consumption and HIV disease markers CD4 cell count and HIV RNA level, stratified by HAART use, using multivariable regression. Results: No significant differences in CD4 cell count or HIV RNA level were found across the categories of alcohol consumption for patients who were not receiving HAART. However, among patients who were receiving HAART, log HIV RNA levels were significantly higher in those with moderate (2.17 copies/ml) and at-risk (2.73 copies/ml) alcohol use compared with none (1.73 copies/ml;p= 0.006). CD4 cell counts in those with moderate (368 cells/μl) and at-risk (360 cells/μl) alcohol use were lower than for subjects who reported none (426 cells/μl;p= 0.07). Conclusion: Among patients who have a history of alcohol problems and are receiving antiretroviral treatment, alcohol consumption was associated with higher HIV RNA levels and lower CD4 counts. No comparable association was found for similar patients who were not receiving HAART. Addressing alcohol use in HIV-infected patients, especially those who are receiving HAART, may have a substantial impact on HIV disease progression.
Solvent-driven symmetry of self-assembled nanocrystal superlattices—A computational study

The preference of experimentally realistic sized 4-nm facetted nanocrystals (NCs), emulating Pb chalcogenide quantum dots, to spontaneously choose a crystal habit for NC superlattices (Face Centered Cubic (FCC) vs. Body Centered Cubic (BCC)) is investigated using molecular simulation approaches. Molecular dynamics simulations, using united atom force fields, are conducted to simulate systems comprised of cube-octahedral-shaped NCs covered by alkyl ligands, in the absence and presence of experimentally used solvents, toluene and hexane. System sizes in the 400,000–500,000-atom scale followed for nanoseconds are required for this computationally intensive study. The key questions addressed here concern the thermodynamic stability of the superlattice and its preference of symmetry, as we vary the ligand length of the chains, from 9 to 24 CH2 groups, and the choice of solvent. We find that hexane and toluene are “good” solvents for the NCs, which penetrate the ligand corona all the way to the NC surfaces. We determine the free energy difference between FCC and BCC NC superlattice symmetries to determine the system's preference for either geometry, as the ratio of the length of the ligand to the diameter of the NC is varied. We explain these preferences in terms of different mechanisms in play, whose relative strength determines the overall choice of geometry. © 2012 Wiley Periodicals, Inc.
325 EFFECT OF HYPER- AND HYPOTHYROIDISM ON SERUM GROWTH HORMONE (rGH) IN THE DEVELOPING RAT

325 EFFECT OF HYPER- AND HYPOTHYROIDISM ON SERUM GROWTH HORMONE (rGH) IN THE DEVELOPING RAT
Visual stimulation of saccades in magnetically tethered Drosophila.

Flying fruit flies, Drosophila melanogaster, perform `body saccades', in which they change heading by about 90° in roughly 70 ms. In free flight, visual expansion can evoke saccades, and saccade-like turns are triggered by similar stimuli in tethered flies. However, because the fictive turns in rigidly tethered flies follow a much longer time course, the extent to which these two behaviors share a common neural basis is unknown. A key difference between tethered and free flight conditions is the presence of additional sensory cues in the latter, which might serve to modify the time course of the saccade motor program. To study the role of sensory feedback in saccades, we have developed a new preparation in which a fly is tethered to a fine steel pin that is aligned within a vertically oriented magnetic field, allowing it to rotate freely around its yaw axis. In this experimental paradigm, flies perform rapid turns averaging 35° in 80 ms, similar to the kinematics of free flight saccades. Our results indicate that tethered and free flight saccades share a common neural basis, but that the lack of appropriate feedback signals distorts the behavior performed by rigidly fixed flies. Using our new paradigm, we also investigated the features of visual stimuli that elicit saccades. Our data suggest that saccades are triggered when expanding objects reach a critical threshold size, but that their timing depends little on the precise time course of expansion. These results are consistent with expansion detection circuits studied in other insects, but do not exclude other models based on the integration of local movement detectors.
The relationship of breathing pattern to central chemoreceptor activity in infantile apnea

In order to assess the relationship of breathing pattern to the central chemoreceptor activity in infantile apnea, we studied 18 infants referred to our regional apnea center with 12 hour nocturnal pneumocardiograms and ventilatory response to 2% and 4% carbon dioxide inhalation. 70% of the infants had normal pneumocardiograms and 60% of the infants had normal ventilatory response to CO2. Nine infants (45%) had normal results in both tests. Our results indicate that in infants with a normal breathing pattern as assessed by pneumocardiogram 75% had normal central chemoreceptor activity, while 37.5% of infants with abnormal breathing pattern had abnormal ventilatory response to CO2.
POLYMYOSITIS ASSOCIATED WITH MONOCLONAL GAMMOPATHY

Abstract Three patients presented with gradual onset of proximal muscle weakness. Electromyography and muscle biopsy were abnormal in each patient and typical of myositis. All three had an IgG x monoclonal paraprotein in the serum. Examination of muscle biopsy specimens by direct immunofluorescence revealed linear deposits of IgG x along the sarcolemmal basement membrane of individual fibres. Stains for λ light chains, other immunoglobulins, and complement components were negative. Plasmapheresis and immunosuppressive drugs produced clinical improvement in all three patients. Muscle biopsies were taken from two of the patients after plasma exchange and drug therapy and showed no immune deposits. These observations suggest a possible cause-and-effect relation between the serum paraprotein and the inflammatory myopathy in these patients.
Single-turnover kinetics of Saccharomyces cerevisiae inorganic pyrophosphatase.

Soluble inorganic pyrophosphatase (PPase), which converts inorganic pyrophosphate (PPi) into usable phosphate, is almost universally present as a central enzyme of phosphorus metabolism and uses divalent metal ion as a necessary cofactor. PPase from Saccharomyces cerevisiae (Y−PPase) is the best studied with respect to both structure and mechanism. Here we report the first combined use of stopped flow and quenched flow techniques to study the PPase reaction in both the forward (PPi hydrolysis) and back (PPi synthesis) directions. The results of these studies permit direct comparison of different divalent metal-ion effects (Mg2+, Mn2+, Co2+) on microscopic rate constants at pH 7.0. For the Mn−enzyme, on which all of the high-resolution X-ray studies have been conducted, they demonstrate that the rate-determining step changes as a function of pH, from hydrolysis of enzyme-bound PPi at low pH to release of the more tightly bound Pi at high pH. They also provide evidence for two kinetically important forms of...
Computed tomography assessment of response to therapy: tumor volume change measurement, truth data, and error.

RATIONALE AND OBJECTIVES: This article describes issues and methods that are specific to the measurement of change in tumor volume as measured from computed tomographic (CT) images and how these would relate to the establishment of CT tumor volumetrics as a biomarker of patient response to therapy. The primary focus is on the measurement of lung tumors, but the approach should be generalizable to other anatomic regions. MATERIALS AND METHODS: The first issues addressed are the various sources of bias and variance in the measurement of tumor volumes, which are discussed in the context of measurement variation and its impact on the early detection of response to therapy. RESULTS AND RESOURCES: Research that seeks to identify the magnitude of some of these sources of error is ongoing, and several of these efforts are described herein. In addition, several resources for these investigations are being made available through the National Institutes of Health-funded Reference Image Database to Evaluate Response to therapy in cancer project, and these are described as well. Other measures derived from CT image data that might be predictive of patient response are described briefly, as well as the additional issues that each of these metrics may encounter in real-life applications. CONCLUSIONS: The article concludes with a brief discussion of moving from the assessment of measurement variation to the steps necessary to establish the efficacy of a metric as a biomarker for response.
A theoretical study of electronic and vibrational properties of neutral, cationic, and anionic B24 clusters

The equilibrium geometries, electronic and vibrational properties, and static polarizability of B24, B, and B clusters are reported here. First-principles calculations based on density functional theory predict the staggered double-ring configuration to be the ground state for B24, B, and B, in contrast to the quasi-planar structure observed in small neutral and ionized Bn clusters with n ≤ 15. Furthermore, the (4 × B6) tubular structure is found to be relatively stable in comparison to the 3D cage structure. The presence of delocalized π and multicentered σ bonds appears to be the cause of the stability of the double-ring and tubular isomers. For the ground state of B24, the lower and upper bound of the electron affinity is 2.67 and 2.81 eV, respectively, and the vertical ionization potential is 6.88 eV. Analysis of the frequency spectrum of the double-ring and tubular isomers reveals the characteristic vibrational modes typically observed in carbon nanotubes. The corresponding IR spectrum also reflects the presence of some of these characteristic modes in the neutral and ionized B24, suggesting that double-ring and tubular structures can be considered as the building blocks of boron nanotubes. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Polo-like Kinase1 Is Required for Recruitment of Dynein to Kinetochores during Mitosis

Kinetochore dynein has been implicated in microtubule capture, correcting inappropriate microtubule attachments, chromosome movement, and checkpoint silencing. It remains unclear how dynein coordinates this diverse set of functions. Phosphorylation is responsible for some dynein heterogeneity (Whyte, J., Bader, J. R., Tauhata, S. B., Raycroft, M., Hornick, J., Pfister, K. K., Lane, W. S., Chan, G. K., Hinchcliffe, E. H., Vaughan, P. S., and Vaughan, K. T. (2008) J. Cell Biol. 183, 819–834), and phosphorylated and dephosphorylated forms of dynein coexist at prometaphase kinetochores. In this study, we measured the impact of inhibiting polo-like kinase 1 (Plk1) on both dynein populations. Phosphorylated dynein was ablated at kinetochores after inhibiting Plk1 with a small molecule inhibitor (5-Cyano-7-nitro-2-(benzothiazolo-N-oxide)-carboxamide) or chemical genetic approaches. The total complement of kinetochore dynein was also reduced but not eliminated, reflecting the presence of some dephosphorylated dynein after Plk1 inhibition. Although Plk1 inhibition had a profound effect on dynein, kinetochore populations of dynactin, spindly, and zw10 were not reduced. Plk1-independent dynein was reduced after p150Glued depletion, consistent with the binding of dephosphorylated dynein to dynactin. Plk1 phosphorylated dynein intermediate chains at Thr-89 in vitro and generated the phospho-Thr-89 phospho-epitope on recombinant dynein intermediate chains. Finally, inhibition of Plk1 induced defects in microtubule capture and persistent microtubule attachment, suggesting a role for phosphorylated dynein in these functions during prometaphase. These findings suggest that Plk1 is a dynein kinase required for recruitment of phosphorylated dynein to kinetochores.
Foreword: Special Section on Stability and Control of Electric Energy Systems With an Increasing Level of Non-Dispatchable Generating Sources

This special section is aimed at addressing important aspects of stability and control related to the increasing penetration of renewable resources. The section is comprised of six papers.