cssi/SciSciGPT-SciSciNet huggingface dataset:
Predictions of moiré excitons in twisted two-dimensional organic–inorganic halide perovskites

Recent breakthrough in synthesizing arbitrary vertical heterostructures of Ruddlesden–Popper (RP) perovskites opens doors to myriad quantum optoelectronic applications. However, it is not clear whether moire excitons and flat bands can be formed in such heterostructures. Here, we predict from first principles that twisted homobilayers of RP perovskite, MA2PbI4, can host moire excitons and yield flat energy bands. The moire excitons exhibit unique and hybridized characteristics with electrons confined in a single layer of a striped distribution while holes localized in both layers. Nearly flat valence bands can be formed in the bilayers with relatively large twist angles, thanks to the presence of hydrogen bonds that strengthen the interlayer coupling. External pressures can further increase the interlayer coupling, yielding more localized moire excitons and flatter valence bands. Finally, electrostatic gating is predicted to tune the degree of hybridization, energy, position and localization of moire excitons in twisted MA2PbI4 bilayers.
Associations of DNA Methylation Mortality Risk Markers with Congenital Microcephaly from Zika Virus: A Study of Brazilian Children Less than 4 Years of Age.

BACKGROUND Zika virus (ZIKV)-associated congenital microcephaly is an important contributor to pediatric death, and more robust pediatric mortality risk metrics are needed to help guide life plans and clinical decision making for these patients. Although common etiologies of pediatric and adult mortality differ, early life health can impact adult outcomes-potentially through DNA methylation. Hence, in this pilot study, we take an early step in identifying pediatric mortality risk metrics by examining associations of ZIKV infection and associated congenital microcephaly with existing adult DNA methylation-based mortality biomarkers: GrimAge and Zhang's mortality score (ZMS). METHODS Mortality measures were calculated from previously published HumanMethylationEPIC BeadChip data from 44 Brazilian children aged 5-40 months (18 with ZIKV-associated microcephaly; 7 normocephalic, exposed to ZIKV in utero; and 19 unexposed controls). We used linear models adjusted for chronological age, sex, methylation batch and white blood cell proportions to evaluate ZIKV and mortality marker relationships. RESULTS We observed significant decreases in GrimAge-component plasminogen activator inhibitor-1 [PAI-1; β = -2453.06 pg/ml, 95% confidence interval (CI) -3652.96, -1253.16, p = 0.0002], and ZMS-site cg14975410 methylation (β = -0.06, 95% CI -0.09, -0.03, p = 0.0003) among children with microcephaly compared to controls. PAI-1 (β = -2448.70 pg/ml, 95% CI -4384.45, -512.95, p = 0.01) and cg14975410 (β = 0.01, 95% CI -0.04, 0.06, p = 0.64) results in comparisons of normocephalic, ZIKV-exposed children to controls were not statistically significant. CONCLUSION Our results suggest that elements of previously-identified adult epigenetic markers of mortality risk are associated with ZIKV-associated microcephaly, a known contributor to pediatric mortality risk. These findings may provide insights for efforts aimed at developing pediatric mortality markers.
AL type cardiac amyloidosis: a devastating fatal disease.

Cardiac amyloidosis is a rare entity with a grave prognosis. Due to the low index of suspicion secondary to non-specific symptoms, it is often diagnosed at an advanced stage with multi-organ involv...
Get It? Got It. Good! Enhancing New Product Acceptance by Facilitating Resolution of Extreme Incongruity:

Abstract Highly innovative products may offer consumers greater benefits than incrementally new products, yet they have a higher failure rate. The current research addresses the challenge faced by new products that are extremely different from existing offerings by drawing on theory regarding the evaluation of schema incongruity. The authors posit that consumers' acceptance of extremely incongruent products will increase when firms use strategies that facilitate cognitive flexibility and thus the likelihood that consumers will be able to make sense of incongruent new products. The authors examine the influence of three manipulations of cognitive flexibility—positive affect, a future (vs. past) launch description, and a cognitive flexibility prime—on evaluations of new products. The results from four experiments show that these factors facilitate participants' ability to make sense of extremely incongruent new products and that incongruity resolution leads to more positive evaluations. The results also ind...
Patient and in-hospital predictors of post-discharge opioid utilization: Individualizing prescribing after radical prostatectomy based on the ORIOLES initiative.

OBJECTIVE Judicious opioid stewardship would match each patient's prescription to their true medical necessity. However, most prescribing paradigms apply preset quantities and clinical judgment without objective data to predict individual use. We evaluated individual patient and in-hospital parameters as predictors of post-discharge opioid utilization after radical prostatectomy (RP) to provide evidence-based guidance for individualized prescribing. METHODS A prospective cohort of patients who underwent open or robotic RP were followed in the Opioid Reduction Intervention for Open, Laparoscopic, and Endoscopic Surgery (ORIOLES) initiative. Baseline demographics, in-hospital parameters, and inpatient and post-discharge pain medication utilization were tabulated. Opioid medications were converted to oral morphine equivalents (OMEQ). Predictive factors for post-discharge opioid utilization were analyzed by univariable and multivariable linear regression, adjusting for opioid reduction interventions performed in ORIOLES. RESULTS Of 443 patients, 102 underwent open and 341 underwent robotic RP. The factors most strongly associated with post-discharge opioid utilization included inpatient opioid utilization in the final 12 hours before discharge (+39.6 post-discharge OMEQ if inpatient OMEQ was >15 vs. 0), maximum patient-reported pain score (range 0-10) in the 12 hours before discharge (+27.6 OMEQ for pain score ≥6 vs. ≤1), preoperative opioid use (+76.2 OMEQ), and body mass index (BMI; +1.4 OMEQ per 1 kg/m2). A final predictive calculator to guide post-discharge opioid prescribing was constructed. CONCLUSIONS Following RP, inpatient opioid use, patient-reported pain scores, prior opioid use, and BMI are correlated with post-discharge opioid utilization. These data can help guide individualized opioid prescribing to reduce risks of both overprescribing and underprescribing.
Islamic Societies to the Nineteenth Century: A Global History

First published in 1988, Ira Lapidus' A History of Islamic Societies has become a classic in the field, enlightening students, scholars, and others with a thirst for knowledge about one of the world's great civilizations. This book, based on fully revised and updated parts one and two of this monumental work,describes the transformations of Islamic societies from their beginning in the seventh century, through their diffusion across the globe, into the challenges of the nineteenth century. The story focuses on the organization of families and tribes, religious groups and states, showing how they were transformed by their interactions with other religious and political communities. The book concludes with the European commercial and imperial interventions that initiated a new set of transformations in the Islamic world, and the onset of the modern era. Organized in narrative sections for the history of each major region, with innovative, analytic summary introductions and conclusions, this book is a unique endeavour.
Special Pavement Requirements for Jet Aircraft Operations

Exhaust heat and blast factors in ground operations of modern jet aircraft applicable to both commercial and military categories; performance requirements and capabilities of conventional portland cement concrete and bituminous concrete pavements subjected to jet aircraft operations; use of nonstandard paving materials and construction methods; critical areas of pavements defined; procedures followed by Corps of Engineers, US Army.
Surgical Management of Proliferative Diabetic Retinopathy

Every case represents a unique surgical challenge. This is especially true when performing surgical interventions in patients with advanced proliferative diabetic retinopathy (PDR) and tractional retinal detachment (TRD). Various tips and surgical techniques for dealing with these challenging cases will be reviewed. However, it is important to remember that the surgical approach will need to be customized for each individual situation.
Does Forced Sexual Contact Have Criminogenic Effects? An Empirical Test of Derailment Theory

According to derailment theory, tactics girls and women use to survive a history of abuse, strategies shaped by their abuse, and societal reactions to it estrange them from non-deviant social networks and situations and increase the likelihood of criminal offending and the application of criminal labels. This process is self-reinforcing, with interactions of substance abuse, sexual deviance, criminal offending, and social control constraining choices through alienation and stigmatization. In short, a dynamic of cumulative disadvantage is set in place that puts some women at greater risk for involvement with the legal system. Empirical evaluation of this theory suggests that alienation from and marginal positions in pro-social networks have parallels in anti-social networks sufficient to decrease the likelihood of criminal offending and contact with crime control agencies.
Visual navigation using a single camera

We assess the usefulness of monocular recursive motion estimation techniques for vehicle navigation in the absence of a model for the environment. For this purpose we extend a recently proposed recursive motion estimator, the Essential filter, to handle scale estimation. We examine experimentally the accuracy with which the motion and position of the vehicle may be computed on an 8000 frame indoors sequence. The issues of sampling time frequency and number of necessary features in the environment are addressed systematically. >
Isolation and characterization of MMS-sensitive mutants of Saccharomyces cerevisiae

We have isolated mutants sensitive to methyl methanesulfonate (MMS) in Saccharomyces cerevisiae. Alleles of rad1, rad4, rad52, rad55 and rad57 were found amoung these mms mutants. Twenty-nine of the mms mutants which complement the existing radiation-sensitive (rad and rev) mutants belong to 22 new complementation groups. Mutants from five complementation groups are sensitive only to MMS. Mutants of 11 complementation groups are sensitive to UV or X rays in addition to MMS, mutants of six complementation groups are sensitive to all three agents. The cross-sensitivities of these mms mutants to UV and X rays are discussed in terms of their possible involvement in DNA repair. Sporulation is reduced or absent in homozygous diploids of mms mutants from nine complementation groups.
Divergent stereoselectivity in the photoaddition of alkanals and medium ring cycloalkenes

Abstract Photocycloaddition of alkanals and cycloheptene, cyclooctene, and 1,5-cyclooctadiene results in stereoisomeric oxetanes, the composition of which depends on the concentration of starting alkene.
Rerum vulgarium fragmenta : From Manuscript to Print

After describing the close relation between Petrarch’s and Dante’s conceptions of canzone form, this article explores the formats followed by Petrarch and his scribe Giovanni Malpaghini in their transcriptions in Vat. Lat. 3195. Giovanni’s traditional horizontal format allows for certain striking effects of collocation (as of 125-126) and for minimal page turns in canzoni; however, the vertical format of the sestinas and the vertical alignment of even-numbered verses in Petrarch’s own transcriptions of sonnets and canzoni suggest a gradually increasing sense of the possibilities of vertical format.
Large fetal sacrococcygeal teratomas: could early delivery improve outcome?

Objective: To determine if gestational age (GA) at delivery or tumor size impacts outcome in neonates with very large sacrococcygeal teratomas (SCTs). Methods: Re
Switched-resistor tuning technique for highly linear G m -C filter design

A new tuning technique is proposed to enable highly linear active G m -C filter design. The transconductance cells of the G m -C filter are tuned using switched resistors (SRs) which change the equivalent reference resistance of each cell. In the master tuning circuit, a feedback loop containing a continuous-time comparator is used to force the equivalent resistance of an SR branch to be equal to that of a switched-capacitor (SC) branch. Thus, using the output of the loop with an automatically adjusted duty cycle, all time constants of the G m -C filter can be tuned simultaneously. A second-order low-pass Butterworth filter model was developed and simulated. The result verified the effectiveness and excellent linearity of the proposed tuning method.
Transport of LRF from CSF to Hypophysial Portal and Systemic Blood and the Release of LH

The capacity of the median eminence to transport LRF from CSF to hypophysial portal blood and the efficacy of intraventricularly and intravenously administered LRF in releasing LH were studied. Ten to 15 min after 125 ng LRF was injected intraventricularly, LRF was detected in portal blood. The maximal rate of transport ranged from 35 to more than 200 pg'min. The rates of transport were much less following the administration of 25 or 5 ng LRF. When these same quantities of LRF were injected intraventricularly into rats with intact pituitary glands, plasma LH levels increased in proportion to the dose of LRF. The releasing action of LRF was long, and 120 min after the administration of 125 ng LRF, the concentration of plasma LH was 40- to 50-fold greater than the control level. Intravenous injection of 5, 25, or 125 ng LRF caused corresponding increases in LH release. Intravenously administered LRF stimulated LH release slightly faster than did LRF given intraventricularly, but the effect of intraventricul...
The international space station X-ray crystallography facility

Abstract This paper presents an overview of the X-ray Crystallography Facility (XCF) currently under development by UAB/CBSE with major support from three contractors. The XCF is to be used on the International Space Station (ISS) for analysis of macromolecular protein crystals grown on the ISS. A brief summary of protein crystal growth experience on the Space Shuttle Orbiter over nearly 15 years is presented, followed by an explanation of reasons for and advantages of a crystal analysis laboratory on the ISS to support protein crystal growth on that space vehicle. The major elements (called prime items) of the XCF are then described, with emphasis on the critical technologies which have been invented or adapted for the ISS and which could also have scientific and commercial applications outside the ISS arena. The crystal preparation prime item is the first of these major elements. The crystal preparation prime item harvests, prepares, and cryogenically preserves crystals by telerobotic techniques completely controlled by crystallographers on the ground. The X-ray diffraction prime item is the second of these major elements. An advanced X-ray source has been invented and developed for this single-crystal diffraction application. This source is described, together with an advanced goniometer and X-ray detector. The third of these major elements is the command, control, and data prime item which implements command, control and data acquisition from remote ground laboratories, as well as by the ISS crew. A realistic operational scenario is postulated for the XCF on the ISS. This scenario has been analyzed in detail to show that the resources required for the XCF operation are well within the bounds of resources to be available on the ISS. A full rack integrated prototype has been constructed, tested, and evaluated and demonstrates full feasibility of the XCF for the ISS application.
General ecology of the cassiduloid urchin Cassidulus caribbearum

Cassidulus caribbearum, a representative of the echinoid order Cassiduloida, occurs in localized populations of high densities (up to 100 m-2) among the islands of the Puerto Rico bank in the eastern Caribbean Sea. These small (up to 35 mm) urchins are burrowers, principally in shallow-water areas with coarse sand bottom. Locomotion is achieved by ditaxic waves, passing from the front to the rear of large movable spines on the lateral portions of the ventral surface; this mechanism is unique among echinoids. Digging was most effective in sand grain sizes most closely approximating those of the environment (0 to 1ϕ). These urchins are somewhat selective deposit feeders, which ingest substrate particles primarily in the size range 0 to 1ϕ. Individuals ingest sand more or less continuously; complete passage of sand through the gut takes an average of 6 h in the laboratory. Aristotle's lantern is present in young juveniles (test length <1.0 mm), but is resorbed before the urchins reach a test length of 5.0 mm. The gut shows similarities in gross morphology to the spatangoid gut. Oxygen consumption is comparable to that of other tropical echinoids of similar wet weight. C. caribbearum broods its large (350 μm) yolky eggs among the aboral spines for 10 to 12 days, at which time young urchins crawl off into the sand. Successive, overlapping broods are produced, so that frequently two broods of different developmental stages are present on a single urchin. Single urchins may brood continuously for up to 4 months or more. Throughout the year, at least 50% of all individuals over 18 mm were found brooding, with a maximum of 85% of all individuals brooding in mid-summer. The sex ratio of the population in all areas sampled was greater than 5 females to 1 male. No evidence of protandric hermaphroditism was found. Growth rate, measured from tagged indivuduals and from increase in median size in population samples, was between 0.5 and 1.0 mm month-1. Mortality was due primarily to predation by the gastropod Cassis tuberosa, although occasional, episodic mortality was caused by physical factors such as heavy storm swells.
Rate of diastolic Ca release from the sarcoplasmic reticulum of intact rabbit and rat ventricular myocytes

The sarcoplasmic reticulum (SR) of cardiac myocytes loses Ca during rest. In the present study, we estimated the rest-dependent unidirectional Ca efflux from the SR in intact rabbit and rat ventricular myocytes. We determined the time course of depletion of the SR Ca content (assessed as the amount of Ca released by caffeine) after inhibition of the SR Ca-ATPase by thapsigargin. Before rest intervals in Na-containing, Ca-free solution, a 3-min preperfusion with 0Na,0Ca solution was performed to deplete Nai but keep the SR Ca content constant. The decrease in Nai should stimulate Ca efflux via Na/Ca exchange when Nao is reintroduced. Thapsigargin treatment was limited to the last 2 min of preperfusion with 0Na,0Ca solution to minimize SR Ca loss before addition of Na, while attaining complete block of the SR Ca pump. Total SR Ca content was estimated from the [Ca]i transient evoked by caffeine, taking into account passive cellular Ca buffering. The time constants for SR Ca loss after thapsigargin were 385 and 355 s, whereas the pre-rest SR Ca content was estimated to be 106 and 114 microM (mumol/l nonmitochondrial cell volume) in rabbit and rat myocytes, respectively. The unidirectional Ca efflux from the SR was similar in the two cell types (rabbit: 0.27 microM s-1; rat: 0.32 microM s-1). These values are also comparable with that estimated from elementary Ca release events ("Ca sparks," 0.2–0.8 microM s-1). Thus, resting leak of Ca from SR may be primarily via occasional openings of SR Ca release channels.(ABSTRACT TRUNCATED AT 250 WORDS)
In vivo kinematic behavior of the radio-capitate joint during wrist flexion–extension and radio-ulnar deviation

The capitate is often considered the "keystone" of the carpus, not simply because of its central and prominent position in the wrist, but also because of its mechanical interactions with neighboring bones. The purpose of this study was to determine in vivo three-dimensional capitate kinematics. Twenty uninjured wrists were investigated using a recently developed, non-invasive markerless bone registration (MBR) technique. Surface contours of the capitate, third metacarpal and radius were extracted from computed tomography images of seven wrist positions and the three-dimensional motions of the capitate and third metacarpal were calculated with respect to the radius in wrist flexion-extension and radio-ulnar deviation. We found that in vivo capitate motion does not simply occur about a single pivot point like a universal joint, as demonstrated by non-intersecting rotation axes for different capitate motions. The distance between flexion and ulnar deviation axes was 3.9+/-2.0 mm, and the distance between extension and ulnar deviation axes was 3.9+/-1.4 mm. Furthermore, capitate axes for males tended to be located more distally than axes for females. However, we believe that this result is related to subject size and not to gender. We also found that there is minimal relative motion between the capitate and third metacarpal during these in vivo wrist motions. These findings demonstrate the complexity of capitate kinematics, as well as the different mechanisms through which wrist flexion, extension, radial deviation and ulnar deviation occur.
Photocurrents on passive and active-passive metals

Abstract Metals generally corrode faster in the light than they do in the dark because of the interaction of photons with the passive film. In order to explain this photo-effect, the passive film is modelled as a semiconductor. This study shows the relationship between the corrosion currents and the photocurrents (light-induced corrosion) of passive and active-passive metals. (An “active” metal generally corrodes freely, while a “passive” metal corrodes very slowly due to protection by a passive film. An “active-passive” metal has a transition where it changes from “active” to “passive” behavior.) The question is what impact do the semiconductor properties of the passive film have on the corrosion rates of the base metal? Photocurrents and corrosion currents were measured on Zr, Ti, Zn, Sn, Fe and Cu immersed in 1N sulfuric acid and/or 1N KOH. The results show that the passive region corresponds to depleted n-type semiconductor. The onset of the photocurrent (flat-band potential) always occurs after the onset of passivity. Non-reversible photocurrent voltammograms often signify the formation of a new oxide film. It is postulated that the active dissolution region corresponds to the degenerate passive film.
Light: Quantum throttling to reveal space-time ripples

Squeezing the uncertainty out of light will bring better optical communications and could flush out Einstein's elusive gravitational waves
Markets for Partially Contractible Knowledge: Bootstrapping versus Bundling

discuss how a seller can appropriate rents when selling knowledge that lacks legal property rights by solving either an expropriation or a valuation problem and then analyze how seller rents increase when a portion of the intellectual property (IP) can be protected. The analysis shows that a sequential strategy in which the protected portion of the IP is sold prior to selling the unprotected IP is superior to selling both portions of the IP as a bundle. (JEL: D23, L14, O31)
High-temperature properties of gases

Computational chemistry is being applied at NASA Ames Research Center to a variety of problems in chemistry, physics, and materials sciences. Supercomputers and modern computational chemistry techniques have provided a powerful new tool to help fill NASA's continuing need for information about the properties of gases and materials as well as their interaction. For example, radiative transition probabilities, spectroscopic constants, bond dissociation energies, transport properties, and chemical reaction rates for molecules can be determined computationally just as reliably as by experiment. Recent results on the radiative transition probabilities of the strongly radiating systems of air species, based on state-of-the-art computational chemistry calculations, are presented and compared with experimental data.
Coronary neovascularization as a specific sign for left atrial appendage thrombus in mitral stenosis

Abstract It is well known that heart rate (HR) fluctuates in time and that this variation is closely related to changes in the neural activity to the heart. 1,2 Therefore, HR variability represents a noninvasive parameter for studying the autonomic control to the heart. Recently, it has been shown that HR variability is a powerful independent prognostic factor in patients with coronary artery disease 3 and a low HR variability count has been found to be related to sudden death. 4 Spectrum analysis of HR may provide further information, since HR variability possesses 2 major components that have been shown to relate to different patterns of neural control to the heart. 5,6 Patients with congestive heart failure (CHF) have a complex abnormality of the autonomic control to the heart 7 that also affects some HR characteristics. 8 These abnormalities may be determined either by a selective reduction of the vagal outflow to the heart or by a more complex abnormality. This investigation was undertaken to evaluate the components of HR variability in normal persons and patients with CHF, and their 24-hour behavior.
Role of the Transition Metal in Metallaborane Chemistry. Reactivity of (Cp*ReH2)2B4H4 with BH3·thf, CO, and Co2(CO)8

The reaction of Cp*ReCl4, [Cp*ReCl3]2, or [Cp*ReCl2]2 (Cp* = η5-C5Me5) with LiBH4 leads to the formation of 7-skeletal-electron-pair (7-sep) (Cp*ReH2)2(B2H3)2 (1) together with Cp*ReH6. Compound 1 is metastable and eliminates H2 at room temperature to generate 6-sep (Cp*ReH2)2B4H4 (2). The reaction of 2 with BH3·thf produces 7-sep (Cp*Re)2B7H7, a hypoelectronic cluster characterized previously. Heating of 2 with 1 atm of CO leads to 6-sep (Cp*ReCO)(Cp*ReH2)B4H4 (3). Both 2 and 3 have the same bicapped Re2B2 tetrahedral cluster core structure. Monitoring the reaction of 2 with CO at room temperature by NMR reveals the formation of a 7-sep, metastable intermediate, (Cp*ReCO)(Cp*ReH2)(B2H3)2 (4), which converts to 3 on heating. An X-ray structure determination reveals two isomeric forms (4-cis and 4-trans) in the crystallographic asymmetric unit which differ in geometry relative to the disposition of the metal ancillary ligands with respect to the Re−Re bond. The presence of these isomers in solution is corr...
Isomer distribution during methyl fucoside, formation by the fischer method. Further support for the previously proposed reaction mechanism☆

Abstract The formation of the four methyl L -fucosides by the Fischer reaction in boiling methanol, with a strongly acidic ion-exchange resin as catalyst, was followed by gas-liquid chromatography of their trimethylsilyl ethers. The initial rapid formation of all four methyl fucosides differs markedly and predictably from the behavior Of D -galactose, which is enantiomeric with L -fucose except for the presence of the hydroxyl group at C-6 in the latter. It also differs somewhat from the behavior of L -arabinose, which is enantiomeric except for the absence of the methyl group at C-5. The initial boiling methanol solution may contain 5% of an L -fucofuranose, in addition to 38% of α- L -fucopyranose and 57% of β- L -fucopyranose. The final equilibrium mixture contains ≈6% of methyl α- L -fucofuranoside, 13% of β- L -fucofuranoside, 54% of methyl α- L -fucopyranoside, and 27% of methyl β- L -fucopyranoside.
Effects of natural sediment features on survival of the phoxocephalid amphipod, Rhepoxynius abronius

Effects of sediment particle size and water content on the survival of the amphipod, Rhepoxynius abronius, were examined by manipulating these natural sediment features within static laboratory microcosms. Mean amphipod survival in fine, uncontaminated, field sediments (≥ 80% silt-clay) can be 15% lower than survival in native sediment. Storage of sediments at 4°C over 7–14 days did not change sediment toxicity, but handling (i.e. elutriation and recombination) of muddy sediments increased toxicity. Sediment particle size and organic content had greater impact on the survival of R. abronius than did sediment water content in modifying amphipod survival, but we could not independently separate the effects of these two sediment variables. A new set of criteria is proposed to interpret toxicity results from the amphipod bioassay in the light of the mortality associated with fine sediment particle size. The efficacy of these criteria to separate mortality caused by fine particles and chemical contaminants was tested by analyzing field survey data from 78 Puget Sound (WA) Urban sites. Using our new criteria, the toxicity of these sediments was found to closely reflect the degree of chemical contamination. We propose that an approach similar to this be undertaken for toxicity tests whenever natural environmental factors induce mortality above background levels.
Hospital policy changes in obstetric patient movement

In preparation for health care reform, many hospitals are contemplating redesigning their physical facilities and altering patient care policies. Uses a large Texas hospital as the subject of this study which was considering implementing policy changes in obstetric patient care along with constructing labour, delivery, recovery room suites. Uses simulation models based on Markovian patient movement to analyse whether their proposed changes will improve overall operational efficiency. The existing as well as proposed obstetric patient movement systems were developed and comparisons made based on average length of stay and total per‐patient cost to the hospital. The quantitative models proved useful in improving decision making with regard to the alternatives. Argues that the methodology can be extended to other hospitals who seek to streamline patient movement to enhance efficiency and patient convenience.
THE EFFECT OF DECREASING MORTALITY ON THE PREVALENCE OF CEREBRAL PALSY (CP) IN A GEOGRAPHICALLY BASED COHORT OF VERY LOW BIRTH WEIGHT (VLBW) INFANTS BORN 1982 TO 1994 ♦ 1231

This study was designed to analyze whether increasing survival of VLBW infants during the 1980's and 1990's has increased risk of CP among survivors. The study cohort consisted of 2076 consecutively born infants, with birth weight 500 to 1500 gms and no major anomaly, born 7/1/82 - 6/30/94 to a resident of a 17-county region in North Carolina. 199 infants (10%) were lost to follow-up. At one year of age, 1282 (94%) of the 1369 surviving infants were examined at our medical center. The diagnosis of CP was made only if the examining pediatrician and a pediatric physical therapist agreed on the diagnosis. To analyze trends across time we categorized infants into six two-year epochs according to year of birth, and applied the Cochran-Armitage X2 to 2 × 6 tables for the binary outcomes of CP and mortality. In the Table “healthy” refers to survival without CP; “CP rate”, to the number of CP cases /100 live births; and “CP risk”, to the number of CP cases /100 survivors. Mortality was fairly constant through 1990 and then began to decrease in 1990-94 [p < 0.001]. The risk of CP was constant from 1982 to 1988, decreased slightly 1988-90, and was lowest in 1990-94 [p = 0.003]. These secular trends in mortality and CP risk remained significant when adjusting for birth weight, gestational age, and gender. Thus, the increasing survival of VLBW infants in the 1980's and 1990's has not resulted in an increased risk of CP among survivors.
OH reaction kinetics of gas-phase α- and γ-hexachlorocyclohexane and hexachlorobenzene

Rate constants for the gas-phase reactions of the hydroxyl radical (OH) with α- and γ-hexachlorocyclohexane (α- and γ-HCH) and hexachlorobenzene (HCB) were measured over the temperature range 346−386 K. The experiments were carried out in He diluent gas at approximately 1 atm, in a 160-mL quartz chamber. OH was produced by the photolysis of ozone in the presence of H2O, and reactants in the chamber were monitored by online mass spectrometry. The rate constants measured at elevated tem peratures were extrapolated by the Arrhenius equation, and OH reaction rate constants at 298 K were estimated for each compound. These rate constants at 298 K (in units of 10-13 cm3 s-1) were α-HCH, 1.4; γ-HCH, 1.9; and HCB, 0.27. Atmospheric lifetimes based on OH reactions (τOH) were also estimated (in units of days): α-HCH, 120; γ-HCH, 96; and HCB, 940. These relatively high atmospheric lifetimes indicate that these compounds can be transported great distances through the atmosphere before removal processes associated wit...
A missense mutation in the neutrophil cytochrome b heavy chain in cytochrome-positive X-linked chronic granulomatous disease.

Abstract A membrane-bound cytochrome b, a heterodimer formed by a 91-kD glycoprotein and a 22-kD polypeptide, is a critical component of the phagocyte NADPH-oxidase responsible for the generation of superoxide anion. Mutations in the gene for the 91-kD chain of this cytochrome result in the X-linked form of chronic granulomatous disease (CGD), in which phagocytes are unable to produce superoxide. Typically, there is a marked deficiency of the 91-kD subunit and the cytochrome spectrum is absent (X- CGD). In a variant form of CGD with X-linked inheritance, affected males have a normal visible absorbance spectrum of cytochrome b, yet fail to generate superoxide (X+ CGD). The size and abundance of the mRNA for the 91-kD subunit and its encoded protein were examined and appeared normal. To search for a putative mutation in the coding sequence of the 91-kD subunit gene, the corresponding RNA from an affected X+ male was amplified by the polymerase chain reaction and sequenced. A single nucleotide change, a C----A transversion, was identified that predicts a nonconservative Pro----His substitution at residue 415 of the encoded protein. Hybridization of amplified genomic DNA with allele-specific oligonucleotide probes demonstrated the mutation to be specific to affected X+ males and the carrier state. These results strengthen the concept that all X-linked CGD relates to mutations affecting the expression or structure of the 91-kD cytochrome b subunit. The mechanism by which the Pro 415----His mutation renders the oxidase nonfunctional is unknown, but may involve an impaired interaction with other components of the oxidase.
Reduced Tolerance for Heat Stress Environments Caused by Protective Lotions.

There have been complaints of excessive heat after applying skin protective lotions. The purpose of this study was to determine if oil-base or alcohol-base protective lotions interfere with the body's cooling mechanisms during moderate work in heat stress conditions, and if so, then to identify the mechanisms. This was accomplished by evaluating the effect of lotions on thermoregulation as measured by rectal temperatures, local sweat rates, and total water losses during exercise at elevated temperatures. In comparison to the control, after about thirty minutes, the skin lotion tests resulted in a more hyperthermic condition, as measured by rectal temperatures.
Solvent effects on the proton internal chemical shifts of some meta-substituted nitrobenzenes

Abstract The proton chemical shifts in 3-X-nitrobenzenes (X = NO 2 , Br, NH 2 ) were determined in thirteen solvents ranging over dielectric constant of 2 to 60. It was found that the internal chemical shifts taken between pairs of nonequivalent hydrogens with at least one ortho substituent were in generally good agreement with the reaction field theory.
Buprenorphine Is a Weak Partial Agonist That Inhibits Opioid Receptor Desensitization

Buprenorphine is a weak partial agonist at μ-opioid receptors that is used for treatment of pain and addiction. Intracellular and whole-cell recordings were made from locus ceruleus neurons in rat brain slices to characterize the actions of buprenorphine. Acute application of buprenorphine caused a hyperpolarization that was prevented by previous treatment of slices with the irreversible opioid antagonist β-chlornaltrexamine (β-CNA) but was not reversed by a saturating concentration of naloxone. As expected for a partial agonist, subsaturating concentrations of buprenorphine decreased the [Met]5enkephalin (ME)-induced hyperpolarization or outward current. When the ME-induced current was decreased below a critical value, desensitization and internalization of μ-opioid receptors was eliminated. The inhibition of desensitization by buprenorphine was not the result of previous desensitization, slow dissociation from the receptor, or elimination of receptor reserve. Treatment of slices with subsaturating concentrations of etorphine, methadone, oxymorphone, or β-CNA also reduced the current induced by ME but did not block ME-induced desensitization. Treatment of animals with buprenorphine for 1 week resulted in the inhibition of the current induced by ME and a block of desensitization that was not different from the acute application of buprenorphine to brain slices. These observations show the unique characteristics of buprenorphine and further demonstrate the range of agonist-selective actions that are possible through G-protein-coupled receptors.
A large deletion in the CFTR gene in CBAVD

Purpose: Most cystic fibrosis mutation screening methods do not detect large exon deletions or duplications in the cystic fibrosis transmembrane regulator gene. We looked for such mutations in congenital bilateral absence of the vas deferens patients in whom routine screening assays had identified only one or no cystic fibrosis transmembrane regulator gene mutations. Methods: DNA samples from 48 men with congenital bilateral absence of the vas deferens were tested for exonic deletions and duplications in the cystic fibrosis transmembrane regulator gene using a laboratory-developed semiquantitative fluorescent PCR assay. Results: Semi-quantitative fluorescent PCR identified a large deletion in one (2%) of the 48 patients. This patient, previously characterized as carrying only the IVS8-5T mutation, was found to have a deletion of exons 22-24 of the cystic fibrosis transmembrane regulator gene. In a second patient with the IVS8-5T mutation, we identified a one-base pair insertion in exon 17b that disrupted the reading frame. Conclusions: Analysis of the cystic fibrosis transmembrane regulator gene for exon deletions and duplications should be included for complete study of CBAVD patients, especially those considering assisted reproduction.
Polarity and lymphocyte fate determination

Polarity within lymphocytes has been recognized to regulate a variety of processes, including migration, signaling, and the execution of effector function. It has been recently proposed, however, that this polarized behavior may also serve a different purpose in lymphocytes that have not yet encountered their foreign antigen — to coordinate asymmetric cell division. Asymmetric division is an evolutionarily conserved mechanism allowing a single cell to give rise to two distinct daughter cells from inception. In this review, recent findings in polarity and asymmetric division in lymphocytes are discussed.
Parkin Protects against Mitochondrial Toxins and β-Amyloid Accumulation in Skeletal Muscle Cells

Mutations in the ubiquitin ligase-encoding Parkin gene have been implicated in the pathogenesis of autosomal recessive Parkinson disease. Outside of the central nervous system, Parkin is prominently expressed in skeletal muscle. We have found accumulations of Parkin protein in skeletal muscle biopsies taken from patients with inclusion body myositis, a degenerative disorder in which intramyofiber accumulations of the β-amyloid peptide are pathognomonic. In comparing primary cultures of skeletal muscle derived from parkin knock-out and wild-type mice, we have found the absence of parkin to result in greater sensitivity to mitochondrial stressors rotenone and carbonyl cyanide 3-chlorophenylhydrazone, without any alteration in sensitivity to calcium ionophore or hydrogen peroxide. Utilizing viral expression constructs coding for the Alzheimer disease and inclusion body myositis-linked β-amyloid precursor protein and for its metabolic byproducts Aβ42 and C100, we found that parkin knock-out muscle cells are also more sensitive to the toxic effects of intracellular Aβ. We also constructed a lentiviral system to overexpress wild-type Parkin and have shown that boosting the levels of parkin expression in normal skeletal muscle cultures provides substantial protection against both mitochondrial toxins and overexpressed β-amyloid. Correspondingly, exogenous Parkin significantly lowered Aβ levels. These data support the hypothesis that in myocytes parkin has dual properties in the maintenance of skeletal muscle mitochondrial homeostasis and in the regulation of Aβ levels.
Noninvasive cardiac activation imaging of ventricular arrhythmias during drug-induced QT prolongation in the rabbit heart.

Background Imaging myocardial activation from noninvasive body surface potentials promises to aid in both cardiovascular research and clinical medicine. Objective To investigate the ability of a noninvasive 3-dimensional cardiac electrical imaging technique for characterizing the activation patterns of dynamically changing ventricular arrhythmias during drug-induced QT prolongation in rabbits. Methods Simultaneous body surface potential mapping and 3-dimensional intracardiac mapping were performed in a closed-chest condition in 8 rabbits. Data analysis was performed on premature ventricular complexes, couplets, and torsades de pointes (TdP) induced during intravenous administration of clofilium and phenylephrine with combinations of various infusion rates. Results The drug infusion led to a significant increase in the QT interval (from 175 ± 7 to 274 ± 31 ms) and rate-corrected QT interval (from 183 ± 5 to 262 ± 21 ms) during the first dose cycle. All the ectopic beats initiated by a focal activation pattern. The initial beat of TdPs arose at the focal site, whereas the subsequent beats were due to focal activity from different sites or 2 competing focal sites. The imaged results captured the dynamic shift of activation patterns and were in good correlation with the simultaneous measurements, with a correlation coefficient of 0.65 ± 0.02 averaged over 111 ectopic beats. Sites of initial activation were localized to be ~5 mm from the directly measured initiation sites. Conclusions The 3-dimensional cardiac electrical imaging technique could localize the origin of activation and image activation sequence of TdP during QT prolongation induced by clofilium and phenylephrine in rabbits. It offers the potential to noninvasively investigate the proarrhythmic effects of drug infusion and assess the mechanisms of arrhythmias on a beat-to-beat basis.
AN EVALUATION OF STATE ENTERPRISE ZONE POLICIES

Our analysis looks at the impact of state enterprise zones in six states (California, Florida, New Jersey, New York, Pennsylvania, and Virginia) on housing values, occupancy rates, and economic well-being of zone residents. Zones did not lead to increased housing prices or occupancy rates, nor did they positively impact income and employment.
Wearable-based Mobile App for Decision Making: The Case of a Safe Workplace

In this paper, we present the concept for the Decision Compass mobile app, an application based on wearable devices meant to enforce safety in the workplace. We illus-trate how data gathered by wearable devices can identify situations of cognitive-dissonance and may be combined with additional contextual information to identify safety related hazards. Our application is designed not only to alert on safety hazards but also to provide resolutions in cases of explicit regulation violations. Finally, we describe future directions to add customized resolutions based on gradual learning of the individual preferences.
The relation of esteem and vocational counseling to range of incorporation scores

Abstract Range of incorporation scores is a potential outcome measure of vocational counseling. Post-test analysis was used to examine the relation of vocational counseling and esteem to 69 Vietnam veterans' ranges of incorporation scores. Measures of esteem and incorporation for eight professions were obtained from 36 veterans who had just completed 10 hr of group counseling and 33 who were just beginning counseling. ANOVA of the ranges of the incorporation scores indicated that high-esteem veterans had higher ranges than low-esteem veterans ( p p ⩽ .10).
VITAL TOOTH BLEACHING: SENSITIVITY AND PULPAL CONSIDERATIONS

For some patients, sensitivity and discomfort follow vital tooth bleaching. Clinical observations, however, suggest these are reversible episodes with no irreversible long-term effects. Using milder peroxide formulations or gels diminishes postoperative discomfort. The author recommends careful treatment when patients have large restorations, cervical erosion or enamel cracks. Fluoride treatment, sealing restorations and premedication may lessen discomfort.
The use of radiotelemetry to evaluate electrographic seizures in rats with kainate-induced epilepsy

Temporal lobe epilepsy in humans is a chronic condition with a highly variable temporal evolution. Animal models of this disorder have been developed to recapitulate many of the characteristics seen in humans with temporal lobe epilepsy. These animal models generate chronic spontaneous electrographic and motor seizures with a progressive increase in frequency over many months. In order to understand the underlying cellular and molecular mechanisms driving epileptogenesis, a practical means for accurately assessing seizure progression over this extended time period must be devised. In this report, we describe the use of a three-channel radiotelemetry system to record spontaneous electrographic interictal "spikes" and seizure activity from the cortical surface and the two hippocampi. This approach has allowed continuous recording before, during, and several months after kainate-induced status epilepticus. The important advantages of this approach are the potential for long-term continuous electrographic recording with comparatively unrestricted behavior; the disadvantages include increased cost, surgical difficulty and lower frequency-response in the recordings.
The analysis of repeated‐measures data on schizophrenic reaction times using mixture models

Reaction times for schizophrenic individuals in a simple visual tracking experiment can be substantially more variable than for non-schizophrenic individuals. Current psychological theory suggests that at least some of this extra variability arises from an attentional lapse that delays some, but not all, of each schizophrenic's reaction times. Based on this theory, we pursue models in which measurements from non-schizophrenics arise from a normal linear model with a separate mean for each individual, whereas measurements from schizophrenics arise from a mixture of (i) a component analogous to the distribution of response times for non-schizophrenics and (ii) a mean-shifted component. We fit four mixture models within this framework, where the distinctions between models arise from assumptions about the variance of the shifted observations and the exchangeability of schizophrenic individuals. Some of these models can be fit by maximum likelihood using the EM algorithm, and all can be fit using the ECM algorithm, where the covariance matrices associated with the parameters are calculated by the SEM and SECM algorithms, respectively. Bayesian model monitoring using posterior predictive checks is invoked to discard models that fail to reproduce certain observed features of the data and to stimulate the development of better models.