cssi/SciSciGPT-SciSciNet huggingface dataset:
Boryl/Borane Interconversion and Diversity of Binding Modes of Oxygenous Ligands in PBP Pincer Complexes of Rhodium

A series of Rh complexes derived from a PBP-type pincer ligand have been synthesized and characterized. It was previously reported that reaction of [(COD)RhCl]2 with 2,2′-bis(diisopropylphino)triphenylborane (1) resulted in a mixture of complexes containing a Z-type borane interaction (2-Cl), a boryl pincer (3a-Cl), and a η2 binding of the B–Ph bond to Rh (4-Cl). In this work, we demonstrate that analogous complexes are accessible by replacement of chloride with potentially bidentate acetylacetonate, carboxylate, and trifluoromethanesulfonate ligands. In addition, a new type of isomer was observed in complexes with acetate and pivalate, where the carboxylate bridges between Rh and B (3b-OAc, 3b-OPiv). All of these types of complexes are isomeric, and the preference for particular isomers for different anionic ligands varies. These isomers differ and are related by a change in the coordination mode of the oxygenous ligands and the migration of the Ph group between B and Rh.
Solution to EMI with indirect earthing of electronic equipment

This paper describes the procedure to find solution to electro-magnetic interference for equipment which are earthed indirectly or where passive earthing is implemented. There are situations where the equipment or the internal circuitry cannot be earthed and only certain parts of the equipment mandates the earth connection. Few examples are pressure sensor mounted on gas pipelines, RTD probe mounted on furnaces etc… In a particular case different methods were tried including filters, ferrites and protection devices, and finally the problem is solved with the help of bypass capacitor. This paper explains how the analysis is performed and how reached at the solution.
Telehealth is Face-to-Face Service Delivery

The Commentary contests the increasingly outdated and narrow use of the terminology 'face-to-face' (often abbreviated as F2F) to connote clinical interactions in which both the client and the practitioner are physically present in the same room or space. An expanded definition is necessary because when delivered synchronously via videoconferencing, telehealth also provides face-to-face services (i.e., the practitioner and the client view each other's faces). Terminology that uses face-to-face to connote only in-person care is limiting and perpetuates language that is out of line with progressive US regulatory language and broad interpretation within existing regulatory language. It is this author's hope that this commentary will raise awareness of the important policy implications associated with this seemingly minor distinction in terminology and impact the lingering misapplication of the term, face-to-face.
A SYSTEMATIC REVIEW ON APP-BASED INTERVENTIONS RELATED TO ALZHEIMER’S DISEASE OR DEMENTIA

Hundreds of smartphone applications are available to support people with Alzheimer’s disease or dementia (AD/dementia) and their caregivers. Smartphone applications may provide a unique and effective means of administering interventions. The purpose of this study was to systematically search and describe the literature on mobile apps used in interventions on AD/dementia and to evaluate the potential of apps to be implemented in AD/dementia interventions. A systematic review was conducted in April 2016 using a set of predetermined search terms in several scientific journal databases. Only English articles pertaining to interventions using smartphone apps were included in the final sample. App functions, target user groups, country, app platform and study design were coded for each study in the final sample. A final sample of 11 studies identified for this review were primarily feasibility and pilot studies with small sample sizes. Studies were mostly conducted in Europe, with Android being the preferred platform. Functions of the mobile apps mainly focused on occupational therapy to support people with AD/dementia, and cognitive assessment to allow early screening of cognitive impairment. Findings of the review provide support for the use of app-based interventions on AD/dementia. The lack of large sample studies with rigorous research design using mobile phone apps may signal a need for additional studies on the potential use of mobile apps to assist individuals with mild or moderate AD/dementia, their family caregivers and health professionals. Additional concerns include the reliability and validity of cognitive assessment tool administered by mobile apps.
Evaluation of radiation levels of various syringe shields containing Sm-153 lexidronam

2114 Objectives : Syringe shields are an essential component in the radiation safety program in a nuclear medicine department. Our facility evaluated radiation levels from Sm-153 lexidronam (Quadramet, Cytogen Corp, Princeton NJ), a mixed beta/gamma emitter having multiple beta (640-810 kev) and gamma (103 kev) emissions, utilizing various syringe shields. Methods : Three specific 5-ml syringe shields were evaluated including: Pro-Tec V (Biodex Medical, Shirley, NY), a tungsten shield with a lead glass window; Pro-Tec IV, (Biodex Medical, Shirley, NY), a total lead glass shield; a prototype beta syringe shield (Biodex Medical, Shirley, NY) consisting of lead encapsulated in acrylic with an acrylic window. Sm-153 lexidronam (127.3 mCi in 2.6 ml) was drawn into a 5-ml syringe and placed in the respective syringe shield. Radiation levels were measured at three or four specific locations on the surface of the shield using 3 x 3 mm thermoluminescent dosimeters (TLD) (Landauer Inc). Following placement, TLD’s were exposed for 30 minutes, removed and sent to Landauer for radiation exposure readings. In addition, two TLD’s were placed on an unshielded Sm-153 lexidronam dose (5 ml syringe) and exposed for 15 minutes, removed and sent to Landauer for radiation exposure readings. All radiation readings were corrected for activity decay. Results : Results of the study demonstrated greater than 99% attenuation from Sm-153 lexidronam for all syringe shields evaluated. The highest radiation reading on the surface of the unshielded Sm-153 lexidronam dose (127.3 mCi in a 5 ml syringe) was 205,614 mrad/hr. Radiation readings from the surface of the tungsten/leaded glass syringe shield (Pro-Tec V) were 440 mrad/hr (mean) and 317 mrad/hr for the tungsten and lead glass component, respectively. Radiation reading on the surface of the lead glass syringe shield (Pro-Tec IV) was 335 mrad/hr (mean). The radiation readings from the surface of the prototype beta syringe shield were 147 mrad/hr (mean) and 5,516 mrad/hr for the acrylic/lead and acrylic window, respectively. The greatest reduction in radiation levels was noted for the lead/acrylic component of the beta syringe shield, however, high radiation levels were also observed for the acrylic window component. The greatest overall reduction in radiation levels was measured using the leaded glass syringe shield (Pro-Tec IV). Conclusions : Greater than 99% attenuation was measured from Sm-153 lexidronam for all syringe shields evaluated. The greatest overall reduction in radiation levels was observed using the leaded glass syringe shield (Pro-Tec IV) which we are currently using in our nuclear medicine department.
An Analysis and Visualization Tool for Case Study Learning of Linguistic Concepts

We present an educational tool that integrates computational linguistics resources for use in non-technical undergraduate language science courses. By using the tool in conjunction with evidence-driven pedagogical case studies, we strive to provide opportunities for students to gain an understanding of linguistic concepts and analysis through the lens of realistic problems in feasible ways. Case studies tend to be used in legal, business, and health education contexts, but less in the teaching and learning of linguistics. The approach introduced also has potential to encourage students across training backgrounds to continue on to computational language analysis coursework.
The NOAA/CIMSS ProbSevere Model: Incorporation of Total Lightning and Validation

AbstractThe empirical Probability of Severe (ProbSevere) model, developed by the National Oceanic and Atmospheric Administration (NOAA) and the Cooperative Institute for Meteorological Satellite St...
Erosion of Metal Matrix Composites

Abstract Erosive wear of metal matrix composites is dependent on the properties of each of the constituents of the target, the properties and kinetic energy of the erodent, the size of the microstructure relative to the impact-affected zones, and the angle of impact. With additional dependent variables associated with the above factors, the mechanisms of erosion of metal matrix composites hinge on the material systems used and the erosion environment. An understanding of the rules governing metal matrix composite erosion can be developed by considering elements of the process, and where possible, contrasting these to some of the better understood erosion mechanisms of homogeneous materials. A simple reinforcement configuration in a composite with continuous, parallel fibres is suited for an initial analysis. For single or multiple impacts perpendicular to the direction of the fibres, the resulting crater's periphery is elliptical with the smaller axis corresponding to the direction of the fibres, i.e. the path of the greatest deformation constraint. If the impact particle trajectory is parallel to the fibres, the deformation penetration into the target surface is impeded more than lateral flow. Since the anisotropy of this type of composite is greater than that of a metal target, the flow asymmetry is more severe. For repeated impacts at one location, the kinetic energy lost in the formation of the crater by plastic deformation is affected by fibre reinforcement. As a result of local fibre fragmentation and work hardening during the repeated impacts the energy lost by plastic deformation approaches the value for the matrix for all fibre volume fractions and orientations. Particular erosion mechanisms depend on the relative size of an impact-produced crater and the damaged region in the composite's surface. The probability of contact of either phase or both simultaneously depends on the geometric features, spacing of phases and relative size of the microstructure of the composite. When the impact crater is small with respect to the dimensions of the constituents in the target face, the initial erosion depends on a combination of the erosion rates of the constituents, however, the surface does not remain plane, and the modified impact angle perturbs the erosion conditions. If the deformation crater is much larger than the size and spacing of the constituents in the microstructure, the combined phases contribute to the erosion properties, and these are independent of the location of the impact. The process, however, is dependent on the angle of the stream of erosive particles. Erodent particles are not rigid and consequently deform and fragment. Short-fibre α-Al 2 O 3 in a 6061 aluminum alloy, eroded by either SiC or Al 2 O 3 , deteriorates at a higher rate with the harder and tougher SiC. Other investigated systems are considered in this review. Because of the many variables associated with erosion of MMCs, improved definition of experimental techniques and analytical characterization of composites are necessary.
Statistics in Everyday Life

Often, when we are blazing a trail through the woods in unfamiliar territory, we get so caught up in cutting through the surrounding brambles that we lose track of the bigger forest in which we are (possibly) lost. Now that we have arrived at a clearing and have survived the challenge of finding our way, we can take stock of what we have accomplished and look forward to future prospects.
Pharmacologic Management of Acute Anaphylaxis

Prompt recognition and treatment of anaphylaxis are essential to assuring favorable clinical outcomes. Anaphylaxis has been defined as a serious allergic reaction that is rapid in onset and may cause death and is characterized by acute respiratory compromise and/or profound hypotension after injection or ingestion of an allergen. Once recognized, epinephrine is the treatment of choice and must be administered immediately, preferably via the intramuscular (IM) route in the anterolateral thigh and repeated every 5 min until clinical improvement. Other key measures include calling the emergency response team for assistance (i.e., 911); placing hypotensive patients in the supine position to improve cardiac output; maintenance of the airway; high flow oxygen; obtaining intravenous access; fluid resuscitation with crystalloid (i.e., normal saline) in the absence of a favorable response to IM epinephrine; and failing a response to all aforementioned interventions including IM epinephrine, intravenous administration of epinephrine, or a vasopressor agent (e.g., vasopressin). Glucocorticoids and antihistamines are generally recommended but considered secondary ancillary drugs. Following recovery, patients must be educated on future avoidance of causative agents and trained on self-administration of epinephrine with an auto-injector device, for future anaphylactic events after unforeseen allergen exposure.
Focusing the Inquiry: Specificity in the Merger Guidelines and Elsewhere

In June of 1982, the Department of Justice and the Federal Trade Commission issued revised merger guidelines.' The drafters had to choose between very general standards, that permit all relevant factors to be considered, and more specific bright line standards that, while easier to apply, might omit important factors. This choice is not unique to merger law. The same tradeoffs are also made in many other areas of antitrust in deciding whether to adopt the rule of reason or rules of per se illegality, or any of the gradations in between.2 A common reaction to the new Guidelines is that they err on the side of considering too many factors.3 They are seen as too vague and general, reducing to some extent the certainty and predictability of the old merger law.4 There is usually an honest recognition that the old law was occasionally too extreme in the other direction, and that some reform was needed to correct a situation where, in Justice Stewart's words, the only rule was that "the Government always wins."'5 The
MathChat: Computational Mathematics via a Social Machine

The main question of this research is: How does a social machine discover algorithmic mathematical knowledge? A social machine is a system of humans and computers engaged in some purposeful activity. To address the main question, an empiric and theoretical framework for algorithmic mathematical knowledge discovered by the social machine is proposed. The framework is derived from findings in Distributed Cognition documenting how collaborators evolve a mathematical algorithm. By combining Distributed Cognition with the standard Message Passing Model of Distributed Computing, a formalism is introduced to specify the activities of the social machine and its algorithmic knowledge. Furthermore, the software system MathChat is introduced which provides an online environment for social machines engaged in mathematical computations. An application of MathChat in network analysis education is described which outlines a social machine covered by the proposed framework.
Patterns of workplace discrimination across broad categories of disability.

OBJECTIVE The aim of this study was twofold: (a) to explore patterns of discrimination in relation to broad-basis categories of disability and (b) to investigate patterns of discrimination between allegations derived from charging parties with sensory impairments versus those with nonsensory impairments. Basis categories included physical, behavioral, neurological, and sensory impairments. RESEARCH METHOD Database mining, descriptive analysis, and Pearson's chi-square analyses were utilized to compare broad-basis categories. RESULTS In general, regardless of disability type, individuals experience the highest frequency and proportion of workplace discrimination in the areas of termination and reasonable accommodations. However, there are significant differences in the workplace discrimination experiences of the four broader groups. CONCLUSIONS Noteworthy differences exist regarding the experience of workplace discrimination among basis categories of disability, especially with respect to sensory impairment. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
Detection of Low-Frequency Mutations and Identification of Heat-Induced Artifactual Mutations Using Duplex Sequencing

We present a genome-wide comparative and comprehensive analysis of three different sequencing methods (conventional next generation sequencing (NGS), tag-based single strand sequencing (e.g., SSCS), and Duplex Sequencing for investigating mitochondrial mutations in human breast epithelial cells. Duplex Sequencing produces a single strand consensus sequence (SSCS) and a duplex consensus sequence (DCS) analysis, respectively. Our study validates that although high-frequency mutations are detectable by all the three sequencing methods with the similar accuracy and reproducibility, rare (low-frequency) mutations are not accurately detectable by NGS and SSCS. Even with conservative bioinformatical modification to overcome the high error rate of NGS, the NGS frequency of rare mutations is 7.0 × 10−4. The frequency is reduced to 1.3 × 10−4 with SSCS and is further reduced to 1.0 × 10−5 using DCS. Rare mutation context spectra obtained from NGS significantly vary across independent experiments, and it is not possible to identify a dominant mutation context. In contrast, rare mutation context spectra are consistently similar in all independent DCS experiments. We have systematically identified heat-induced artifactual variants and corrected the artifacts using Duplex Sequencing. Specific sequence contexts were analyzed to examine the effects of neighboring bases on the accumulation of heat-induced artifactual variants. All of these artifacts are stochastically occurring rare mutations. C > A/G > T, a signature of oxidative damage, is the most increased (170-fold) heat-induced artifactual mutation type. Our results strongly support the claim that Duplex Sequencing accurately detects low-frequency mutations and identifies and corrects artifactual mutations introduced by heating during DNA preparation.
Delegitimizing a Witness: Composition and Revision in Joshua 22

In Joshua 22, after the Transjordanian tribes fulfill their obligations they construct an altar by the River Jordan. In response, the Cisjordanian tribes assemble to wage war, yet a civil war is averted when they learn that this altar serves no sacrificial purpose. This article argues that Joshua 22 is the product of a base layer, an account of the Transjordanian tribes erecting an altar by the River Jordan, and a supplemental layer that revises and reshapes the cultic function of this altar.
The Confrontation between general relativity and experiment: A 1992 update

The status of experimental tests of general relativity and of theoretical frameworks for analysing them are reviewed. Einstein’s equivalence principle is well supported by experiments such as the Eotvos experiment, tests of special relativity, and the gravitational redshift experiment. Tests of general relativity have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected to half a percent using the binary pulsar, and new binary pulsar systems promise further improvements. The status of the “fifth force” is discussed, along with the frontiers of experimental relativity, including proposals for testing relativistic gravity with advanced technology and spacecraft.
Using Mobile Monitoring to Develop Hourly Empirical Models of Particulate Air Pollution in a Rural Appalachian Community

Most empirical air quality models (e.g., land use regression) focus on urban areas. Mobile monitoring for model development offers the opportunity to explore smaller, rural communities — an understudied population. We use mobile monitoring to systematically sample all daylight hours (7 am to 7 pm) to develop empirical models capable of estimating hourly concentrations in Blacksburg, VA, a small town in rural Appalachia (population: 182 635). We collected ∼120 h of mobile monitoring data for particle number (PN) and black carbon (BC). We developed (1) daytime (12-h average) models that approximate long-term concentrations and (2) spatiotemporal models for estimating hourly concentrations. Model performance for the daytime models is consistent with previous fixed-site and short-term sampling studies; adjusted R2 (10-fold CV R2) was 0.80 (0.69) for the PN model and 0.67 (0.58) for the BC model. The spatiotemporal models had comparable performance (10-fold CV R2 for the PN [BC] models: 0.42 [0.25]) to previou...
Does Race Influence Decision Making for Advanced Heart Failure Therapies

Background Race influences medical decision making, but its impact on advanced heart failure therapy allocation is unknown. We sought to determine whether patient race influences allocation of adva...
Frequency-Selective Planar Coil Architecture Modeling for WPT Access Control

In this paper, an approach to access control in wireless power transfer (WPT) systems via frequency-selective architecture is proposed. We perform modeling of planar square loop resonance behavior in GHz range using Ansys HFSS®. Power transfer efficiency is found from the accepted power and radiated power. Using a multi-coil design, where the transmitter and receiver switch between coils of different resonance frequencies in sync, can provide for effective access control. Modeling results for a prototype coil design that will lead to this functionality are presented and discussed.
Exploring Youtube Marketing Communication Among 200 Leading National Advertisers

This study is designed to explore how 200 leading national advertisers use Youtube.com as their communication tool. Content analysis was utilized for exploring current YouTube marketing communicati...
Effect of PPIs on symptomatic hypocalcemia after thyroidectomy: A retrospective cohort study

Objective To determine differences in incidence and duration of postoperative symptomatic hypocalcemia between those taking and those not taking proton pump inhibitors (PPIs) at the time of total or completion thyroidectomy. Methods A retrospective chart review of adult patients who underwent total or completion thyroidectomy at a tertiary medical center between January 2013 and January 2018 was performed. Development of symptomatic hypocalcemia, duration of symptoms, postoperative parathyroid hormone levels, PPI usage and emergency department (ED) visits were recorded. Results Data from 371 patients were analyzed. Sixty of 371 (16.2%) patients developed symptomatic hypocalcemia. Sixteen of 89 (18.0%) patients on a PPI developed symptomatic hypocalcemia compared to 44 of 282 (15.6%) not on a PPI (P = .63). The overall average duration of symptoms was 4.3 days (SD [SD] 3.77 days). The average duration of symptoms in those on a PPI was 4.8 days (SD 2.8 days) compared to 4.2 days (SD 4.1 days) in those not on a PPI (P = 0.16). Six of 282 patients (2.1%) not taking a PPI had a postoperative ED visit, compared to two of the 89 patients (2.3%) taking a PPI (P = 1.00). Conclusions There was no clinically significant difference in incidence and duration of symptomatic hypocalcemia or ED visits after total or completion thyroidectomy between patients that were and were not taking PPIs perioperatively. While the decision to continue PPI should be made on an individual basis, these data suggest that patients may be counseled to continue their PPI perioperatively without increased risk of symptomatic hypocalcemia. Level of evidence 3.
Constructing many-body dissipative particle dynamics models of fluids from bottom-up coarse-graining

Since their emergence in the 1990s, mesoscopic models of fluids have been widely used to study complex organization and transport phenomena beyond the molecular scale. Even though these models are designed based on results from physics at the meso- and macroscale, such as fluid mechanics and statistical field theory, the underlying microscopic foundation of these models is not as well defined. This paper aims to build such a systematic connection using bottom-up coarse-graining methods. From the recently developed dynamic coarse-graining scheme, we introduce a statistical inference framework of explicit many-body conservative interaction that quantitatively recapitulates the mesoscopic structure of the underlying fluid. To further consider the dissipative and fluctuation forces, we design a novel algorithm that parameterizes these forces. By utilizing this algorithm, we derive pairwise decomposable friction kernels under both non-Markovian and Markovian limits where both short- and long-time features of the coarse-grained dynamics are reproduced. Finally, through these new developments, the many-body dissipative particle dynamics type of equations of motion are successfully derived. The methodologies developed in this work thus open a new avenue for the construction of direct bottom-up mesoscopic models that naturally bridge the meso- and macroscopic physics.
Formation of a single drop of molten steel following bursting of liquid film in a vertical steel plate illuminated by a high energy laser

The formation and dynamics of a single drop of liquid under the influence of gravity can be experienced as everyday phenomena, and have been the subject of scientific investigations since at least the work of Leonardo da Vinci in the early 1500s and Mariotte in the 1680s. Experiences with liquid drops in everyday life are captured by poets and artists as well as scientists, whose theoretical and experimental investigations develop fundamental understanding of drops with size 107 m. This paper presents observations of the formation of a single liquid drop of molten steel following bursting of a liquid film formed by illuminating a steel plate by a high energy laser. The hole morphology is analyzed with a proposed kinematic model of hole expansion for the very early stages in the bursting of the hole. Estimates of the hole eccentricity, area, perimeter, and circularity obtained from the model are presented and discussed. Experimental measurements show that a single drop of liquid steel detaches from the end of a neck that then cools to room temperature. Measurements also show that the liquid drop oscillates while falling under gravity. No satellite drops are observed.
Overview of Icing Research at NASA Glenn

The aviation industry continues to deal with icing-related incidents and accidents on a regular basis. Air traffic continues to increase, placing more aircraft in adverse icing conditions more frequently and for longer periods. Icing conditions once considered rare or of little consequence, such as super-cooled large droplet icing or high altitude ice crystals, have emerged as major concerns for modern aviation. Because of this, there is a need to better understand the atmospheric environment, the fundamental mechanisms and characteristics of ice growth, and the aerodynamic effects due to icing, as well as how best to protect these aircraft. The icing branch at NASA Glenn continues to develop icing simulation methods and engineering tools to address current aviation safety issues in airframe, engine and rotorcraft icing.
Towards high-resolution fat-suppressed T1-mapping of atrial fibrosis in the left atrium: a fit-free three-point method

Background Atrial fibrosis identification by late gadolinium enhancement (LGE) CMR is important as a precursor to atrial fibrillation, and may impact the outcome of catheter ablation. However, the LGE enhancement in the thin atrial wall is difficult to accurately and reproducibly detect. We sought to improve identification of fibrosis through T1-mapping, generating an index of the extracellular volume fraction (ECV). In order to achieve high spatial resolution mapping for a narrow range of relevant T1-values (250-500ms) in a feasible scan time, we applied fit-free T1-mapping with only 3 TI values (3-pt). Preliminary data measuring the ECV of normal myocardium and the aortic valves—a thin fibrotic structure– are presented.
Cancer-associated serum galactosyltransferase activity. Demonstration in an animal model system.

Two different lines of solid tumors were produced in outbred hamsters by subcutaneous injection of polyoma transformed BHK cells. Growth of the tumors correlated with the appearance in serum of an electrophoretically distinct peak of galactosyltransferase: NeuAc-, Gal-free fetuin acceptor activity on polyacrylamide gels. This slow moving peak of enzyme activity (GT-HH) was detected before solid tumors could be grossly observed and the amount of activity in this peak was also found to be linearly related with growth of the tumor. GT-IIH was not detectable in control animals and separated from a faster migrating major area of serum galactosyltransferase activity (GT-IH) found in sera of both control and tumor-bearing hamsters. These two activities were shown to maintain their respective mobilities on re-electrophoresis. Solubilized enzyme derived from excised tumors demonstrated an electrophoretic mobility on polyacrylamide gels identical to that for GT-IIH present in serum from tumor-bearing animals. In contrast, enzyme activity solubilized from livers of both control or tumor-bearing hamsters showed a mobility similar to that of the faster moving serum galactosyltransferase enzyme activity, i.e. GT-IH. In addition, medium derived from nonconfluent BHKpy cells in tissue culture contained galactosyltransferase activity which co-electrophoresed with the slower migrating characteristics of galactosyltransferase activities derived from serum (control and tumor-bearing), solid tumors, liver and BHKpy cells in tissue culture were compared. All kinetic properties were similar with the exception that the Km UDP-galactose of GT-IIH (1.0 X 10(-5) M) was half that of GT-IH (2.0 X 10(-5) M).
Robust time and frequency domain estimation methods in adaptive control

A robust identification method was developed for use in an adaptive control system. The type of estimator is called the robust estimator, since it is robust to the effects of both unmodeled dynamics and an unmeasurable disturbance. The development of the robust estimator was motivated by a need to provide guarantees in the identification part of an adaptive controller. To enable the design of a robust control system, a nominal model as well as a frequency-domain bounding function on the modeling uncertainty associated with this nominal model must be provided. Two estimation methods are presented for finding parameter estimates, and, hence, a nominal model. One of these methods is based on the well developed field of time-domain parameter estimation. In a second method of finding parameter estimates, a type of weighted least-squares fitting to a frequency-domain estimated model is used. The frequency-domain estimator is shown to perform better, in general, than the time-domain parameter estimator. In addition, a methodology for finding a frequency-domain bounding function on the disturbance is used to compute a frequency-domain bounding function on the additive modeling error due to the effects of the disturbance and the use of finite-length data. The performance of the robust estimator in both open-loop and closed-loop situations is examined through the use of simulations.
RE1-silencing transcription factor (REST) and REST-interacting LIM domain protein (RILP) affect P19CL6 differentiation.

During cardiac development, the heart produces the atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). These peptides are found in high levels in cardiomyocytes and, like a number of other embryonic genes, are up-regulated in both failing and hypertrophied ventricles. At the transcriptional level, BNP and ANP genes are regulated through RE1 regulatory element, which binds RE1-silencing transcription factor (REST). REST/NRSF-interacting LIM domain protein (RILP) is required for the nuclear targeting and function of REST. In this study, the role of RILP and REST in cardiomyocyte development using a model system was studied by analyzing the expression of RILP and REST as well as several cardiac-specific genes during P19CL6 cell differentiation. Effects of RILP overexpression and transcriptional regulation of RILP in differentiating P19CL6 cells were also studied. RILP expression is transiently reduced during P19CL6 cell differentiation; however, REST expression remains unchanged. This transient reduction in RILP expression correlates with de-repression of sarcomeric myosin heavy chain, a marker for cardiomyocyte differentiation. Reporter gene analysis shows that RILP gene is down-regulated through 5′-regulatory elements before cardiac-specific gene expression. These results suggest that RILP expression and function control REST action more so than does REST expression and is an important regulatory role in cardiomyocyte differentiation.
Cloning humans? Biological, ethical, and social considerations

There are, in mankind, two kinds of heredity: biological and cultural. Cultural inheritance makes possible for humans what no other organism can accomplish: the cumulative transmission of experience from generation to generation. In turn, cultural inheritance leads to cultural evolution, the prevailing mode of human adaptation. For the last few millennia, humans have been adapting the environments to their genes more often than their genes to the environments. Nevertheless, natural selection persists in modern humans, both as differential mortality and as differential fertility, although its intensity may decrease in the future. More than 2,000 human diseases and abnormalities have a genetic causation. Health care and the increasing feasibility of genetic therapy will, although slowly, augment the future incidence of hereditary ailments. Germ-line gene therapy could halt this increase, but at present, it is not technically feasible. The proposal to enhance the human genetic endowment by genetic cloning of eminent individuals is not warranted. Genomes can be cloned; individuals cannot. In the future, therapeutic cloning will bring enhanced possibilities for organ transplantation, nerve cells and tissue healing, and other health benefits.
Thyrotropin-releasing hormone and phorbol esters stimulate sphingomyelin synthesis in GH3 pituitary cells. Evidence for involvement of protein kinase C.

Abstract Previous studies demonstrated that phorbol esters and thyrotropin-releasing hormone (TRH) stimulated phosphatidylcholine synthesis via protein kinase C in GH3 pituitary cells (Kolesnick, R. N. (1987) J. Biol. Chem. 262, 14525-14530). Since phosphatidylcholine may serve as the precursor for sphingomyelin synthesis, studies were performed to assess the effect of protein kinase C on sphingomyelin synthesis. The potent phorbol ester, 12-O-tetradecanoylphorbol 13-acetate (TPA), stimulated time- and concentration-dependent incorporation of 32Pi into the head group of sphingomyelin in cells short term labeled with 32Pi and resuspended in medium without radiolabel. TPA (10(-7) M) increased incorporation at a rate 1.4-fold of control after 2 h; EC50 congruent to 2 x 10(-9) M TPA. This correlated closely to TPA-induced phosphatidylcholine synthesis; EC50 congruent to 9 x 10(-10) M TPA. TRH (10(-7) M), which activates protein kinase C via a receptor-mediated mechanism, similarly stimulated 32Pi incorporation into sphingomyelin at a rate 1.5-fold of control; EC50 congruent to 5 x 10(-10) M TRH. This correlated closely with TRH-induced phosphatidylcholine and phosphatidylinositol synthesis; EC50 congruent to 2 x 10(-10) and 1.5 x 10(-10) M TRH, respectively. In cells short term labeled with [3H]palmitate, TRH induced a time- and concentration-dependent reduction in the level of [3H]ceramide and a quantitative increase in the level of [3H]sphingomyelin. Compositional analysis of the incorporated [3H]palmitate revealed that TRH increased radiolabel into both the sphingoid base and the fatty acid moieties of sphingomyelin. Similarly, TRH increased incorporation of [3H] serine into sphingomyelin to 145 +/- 8% of control after 3 h. TPA also stimulated these events. Like the effect of TRH on phosphatidylcholine synthesis, TRH-induced sphingomyelin synthesis was abolished in cells "down-modulated" for protein kinase C. In contrast, TRH-induced phosphatidylinositol synthesis still occurred in these cells. These studies suggest that protein kinase C stimulates coordinate synthesis of phosphatidylcholine and sphingomyelin. This is the first report of stimulation of sphingomyelin synthesis via a cell surface receptor.
The Lambert-Eaton myasthenic syndrome.

Publisher Summary The Lambert–Eaton myasthenic syndrome (LEMS) is a rare autoimmune condition where weakness results from a presynaptic abnormality of acetylcholine (ACh) release at the neuromuscular junction. LEMS begins in later life. LEMS may be first discovered when prolonged paralysis follows the use of neuromuscular blocking agents during surgery. Small cell lung cancer (SCLC) is the most common associated cancer. The classical clinical findings of LEMS are weakness, particularly of proximal muscles, reduced or absent muscle stretch reflexes, and dry mouth. The diagnosis can be confirmed by demonstrating characteristic abnormalities on electrodiagnostic studies. Autonomic function tests are abnormal in most LEMS patients, even when there are no clinical signs of autonomic dysfunction. These tests show evidence of sympathetic or parasympathetic dysfunction. LEMS patients with SCLC may have other paraneoplastic syndromes, such as inappropriate ADH secretion (SIADH), sensorimotor neuropathy, or cerebellar degeneration. Clinical features for MG are ocular muscle weakness, limb weakness (predominating in arms), and normal muscle stretch reflexes. Therapy must be tailored for each patient, based on the severity of weakness, underlying disease(s), life expectancy and response to previous treatment. The prognosis in LEMS patients is determined by presence and type of any underlying cancer, presence and severity of any associated autoimmune disease, and severity and distribution of weakness. Overlapping features of MG and LEMS include: clinical features of one condition but facilitation, or lack thereof, typical of the other; clinical and electrodiagnostic patterns typical of one condition initially, but changing to the other later; or electrodiagnostic patterns typical of MG in one muscle, and of LEMS in another. The ultimate diagnosis in patients with mixed features of MG and LEMS may be moot because many treatments are the same for both conditions.
Information transfer: past, present and future.

To provide the health scientist with the information he needs, when he needs it, is an age old problem. Various approaches to its solution are discussed. The remaining impediments to solution are intellectual, not technical or technologic.
Superallowed 0 + →0 + nuclear β decays: A new survey with precision tests of the conserved vector current hypothesis and the standard model

A new critical survey is presented of all half-life, decay-energy, and branching-ratio measurements related to 20 superallowed ${0}^{+}\ensuremath{\rightarrow}{0}^{+}\ensuremath{\beta}$ decays. Compared with our last review, there are numerous improvements: First, we have added 27 recently published measurements and eliminated 9 references, either because they have been superseded by much more precise modern results or because there are now reasons to consider them fatally flawed; of particular importance, the new data include a number of high-precision Penning-trap measurements of decay energies. Second, we have used the recently improved isospin symmetry-breaking corrections, which were motivated by these new Penning-trap results. Third, our calculation of the statistical rate function $f$ now accounts for possible excitation in the daughter atom, a small effect but one that merits inclusion at the present level of experimental precision. Finally, we have re-examined the systematic uncertainty associated with the isospin symmetry-breaking corrections by evaluating the radial-overlap correction using Hartree-Fock radial wave functions and comparing the results with our earlier calculations, which used Saxon-Woods wave functions; the provision for systematic uncertainty has been changed as a consequence. The new ``corrected'' $\mathcal{F}t$ values are impressively constant and their average, when combined with the muon lifetime, yields the up-down quark-mixing element of the Cabibbo-Kobayashi-Maskawa (CKM) matrix, ${V}_{\mathit{ud}}=0.97425\ifmmode\pm\else\textpm\fi{}0.00022$. The unitarity test on the top row of the matrix becomes $|{V}_{\mathit{ud}}|{}^{2}+|{V}_{\mathit{us}}|{}^{2}+|{V}_{\mathit{ub}}|{}^{2}=0.99995\ifmmode\pm\else\textpm\fi{}0.00061$. Both ${V}_{\mathit{ud}}$ and the unitarity sum have significantly reduced uncertainties compared with our previous survey, although the new value of ${V}_{\mathit{ud}}$ is statistically consistent with the old one. From these data we also set limits on the possible existence of scalar interactions, right-hand currents, and extra $Z$ bosons. Finally, we discuss the priorities for future theoretical and experimental work with the goal of making the CKM unitarity test even more definitive.
FATAL HAEMORRHAGE FROM THE INNOMINATE ARTERY AFTER TRACHEOSTOMY: A Case Report

SUMMARY A case of fatal haemorrhage from the innominate artery occurred a week after tracheostomy was performed. Control of the bleeding was tried unsuccessfully by hyperinflation of the cuff of the tracheostomy tube. The mechanism is erosion of the artery by the inferior border of the tracheostomy tube. Since the treatment of massive haemorrhage from the innominate artery is extremely difficult, the avoidance of low tracheostomies and the use of short and properly curved tracheostomy tubes may be effective in prevention of this fatal complication.
Reverse subclavian flap repair of hypoplastic transverse aorta in infancy.

Abstract Background . Management of hypoplastic aortic arch associated with coarctation in infancy can be challenging. Reverse subclavian flap aortoplasty plus coarctation resection offers simplicity without needing foreign material or cardiopulmonary bypass. Methods . Since 1988, 46 of 162 infants less than 3 months undergoing coarctation repair had hypoplastic arch enlargement with reverse subclavian flap aortoplasty. Median age was 11 days; mean weight was 3.2 kg. Thirty-seven patients (80%) had associated cardiac defects including single or multiple ventricular septal defects (14 infants), transposition of the great arteries (7), aortic or mitral stenosis (5), and complete atrioventricular septal defect (5 infants). Twenty-eight patients had pulmonary artery banding; 2 had an arterial switch operation through a separate median sternotomy. Results . There were two hospital deaths: one 4 months postoperatively in a patient requiring a Norwood procedure the next day for underestimated left ventricular hypoplasia; the other of sepsis more than 1 month postoperatively. On follow-up from 1 to 129 months (mean, 38 months), there were five recurrent obstructions: three at the coarctation site treated with balloon dilatation and two at the arch site. Twenty-six children had their heart defects corrected with 29 subsequent operations including an arterial switch operation for transposition of the great arteries/ventricular septal defect (3 infants), relief of aortic or mitral stenosis ± ventricular septal defect closure (5), multiple ventricular septal defect closure (3), a bidirectional Glenn (2), complete atrioventricular septal defect (2), and anomalous left coronary with ventricular septal defect repair (1 infant). Four children await debanding and ventricular septal defect closure or Glenn anastomosis. There have been two late deaths (overall survival, 91%). Conclusions . Reverse subclavian flap aortoplasty is excellent for relief of arch hypoplasia and coarctation in infants with low recurrence rates and acceptable operative and intermediate survival.
Intravenous tissue plasminogen activator and flow improvement in acute ischemic stroke patients with internal carotid artery occlusion.

Background and purpose It has been suggested that intravenous tissue plasminogen activator (TPA) would not lyse the large thrombus associated with internal carotid artery (ICA) occlusion and, therefore, would be ineffective in this setting. Vascular imaging, safety, and outcome of TPA therapy for ICA occlusion is not well described. Our goal was to determine the site of occlusion, early recanalization after TPA infusion, and its relationship to outcome. Methods We reviewed our database of all stroke patients treated with i.v. TPA between July 1997 and July 1999. We identified all cases with carotid occlusion suggested by transcranial Doppler (TCD) and angiography. Occlusion and recanalization were assessed by site including proximal ICA (prICA), terminal ICA (tICA), and middle cerebral artery (MCA). Baseline National Institutes of Health Stroke Scale (NIHSS) scores and follow-up Rankin scores were obtained. Results We treated 20 patients with carotid occlusion (age 63.9 +/- 10.8 years, 11 males, 9 females). Time to TPA infusion after stroke onset was 128 +/- 66 minutes. Baseline NIHSS scores were 16.4 +/- 5.4. Time to follow-up was 3.5 +/- 4.9 months (2 patients were lost to follow-up). Occlusion sites were prICA 40%, tICA 70%, and concurrent MCA 45%. Multiple sites were involved in 10/20 patients (50%). Among patients with pretreatment and posttreatment vascular imaging studies (n = 18), recanalization in the prICA and tICA was complete in 10%, partial in 16%, and none in 74%. MCA recanalization was complete in 35%, partial in 24%, and none in 41%. At follow-up, Rankin 0-1 was found in 8 patients (44%), Rankin 2-3 in 3 (17%), and Rankin 4-5 in 3 (17%). Mortality was 22% (n = 4) including 1 fatal intracerebral hemorrhage. Improvement was closely related to resumption of MCA flow (P Conclusions Most patients did not recanalize their ICA occlusion after intravenous TPA therapy. However, recanalization of associated proximal MCA clot, found in 45% of our patients, or improved MCA collateral flow was strongly associated with good outcome.
In Situ Rheometric Shearing Apparatus at the NIST Center for Neutron Research

Abstract A constant stress Couette cell rheometer has been modified to measure simultaneously the viscometric properties and neutron scattering intensities from the NIST Center for Neutron Research (NCNR) small angle neutron scattering (SANS) spectrometers. The apparatus was constructed to complement scattering radiation experiments of solutions under shear. The apparatus is capable of high accuracy measurements with viscosities that can range over about ten orders of magnitude. Sample plots showing simultaneous measurements of the viscosity and the anisotropic scattering patterns from micellar solutions are presented. The apparatus is easily adapted for light scattering.