cssi/SciSciGPT-SciSciNet huggingface dataset:
An Underpinning of School Inequities: Asthma Absences and Lost Revenue in California Schools.

Author(s): Kreger, Mary; Sargent Cairoli, Katherine; Brindis, Claire D | Abstract: BACKGROUND:Asthma is epidemic in many locations in the United States. Asthma exacerbations pose serious health and education risks for students through school absences, school dropout, and introduction to the juvenile justice system. Accurate school district-level asthma data, currently in short supply, would enable early interventions that focus on specific geographic areas and racial and ethnic subgroups that have higher asthma prevalence. METHODS:To support the development of better local level data systems, we used two California student databases, as well as state education and financial databases, to develop two models to estimate school absences and to extrapolate their economic impact in lost school revenue. RESULTS:Analysis demonstrated subpopulations that are appropriate for early intervention: African American elementary school boys have 9.4 average absences per year, higher than other primary racial and ethnic groups. Students who miss ≥3 school days due to asthma account for $26 million of lost revenue. CONCLUSIONS:Accurate local level asthma data can identify subpopulations of students for whom environmental and treatment programs can be employed to reduce asthma absences and other related outcomes, and to reduce currently lost school revenues. Such programs also may diminish other asthma-related school inequities.
A density functional theory study of hydrogen recombination and hydrogen-deuterium exchange on Ga/H-ZSM-5

Density functional theory calculations have been carried out to determine the thermodynamic stability of various Ga species in gallium-exchanged ZSM-5, the thermodynamics of H2 adsorption, and the most favorable pathway for H2/D2 exchange. The portion of the zeolite associated with Ga was represented by a cluster containing 7, 21, or 33 atoms. The B3LYP hybrid method was used to account for the effects of electron exchange and correlation. The most likely form of Ga expected in freshly exchanged and calcined ZSM-5 is ZGa(OH)2. H2 reduction of this species is projected to produce ZGa(H)(OH) and ZGa(H)2. While the thermodynamics of H2 desorption from ZGa(H)2 are favorable, the process is projected to be slow because of a high activation barrier. The most favorable pathway for H2/D2 exchange over ZGa(H)2 proceeds via Z(D)(Ga(H)2(D)) as an intermediate. Similar calculations have been carried out for H2/D2 exchange over H-ZSM-5.
Home collection of products of conception: Can chromosomal analysis be obtained?

Abstract Introduction The majority of early pregnancy losses are due to chromosomal abnormalities, which can be evaluated by testing the products of conception (POCs). Traditionally, a dilation and curettage (D&C) is recommended to patients to obtain suitable tissue for analysis. This case series sought to determine whether patients with first-trimester pregnancy losses can successfully obtain analysis of POCs if they pass tissue with expectant management or misoprostol, rather than D&C. Materials and methods This is a retrospective cohort study of patients who desired analysis of POCs following an early pregnancy loss. The POCs were collected either at home by patients, or by providers following a D&C, and sent to an outside laboratory for single nucleotide polymorphism (SNP) microarray analysis. Results Of 50 identified patients, chromosomal analysis was successfully completed on: 22/34 (65%) of patients who passed pregnancy with misoprostol, 14/14 (100%) with D&C, and 1/2 (50%) with expectant management (x2, p = 0.03). Analysis was successful up to 9 days after tissue was collected, and 55 days after diagnosis of loss. Conclusion In our study, D&C was the superior method to obtain POCs for chromosomal analysis following a miscarriage, but medical and expectant management still had clinically acceptable success rates as well. Although further study is indicated, this small case series suggests that patient counselling regarding miscarriage management and desired chromosomal analysis should continue to include misoprostol and expectant management as inferior but still appropriate alternatives to D&C.
“The Size of the Self”: Minimalist Selves and Narrative Self-Constitution

This essay responds to skeptical queries directed against narrative by examining two views of the self in contemporary philosophical literature which can be traced back to two differing interpretations of Locke’s account of the relation between persons and selves. On the first (or “narrative self-constitution”) view, a persisting subject exists only by its (essentially, even if only implicitly, narrative) appropriation of different experiences over time. On the other (“minimalist”) view, selfhood is not something actively accomplished, but rather a (pre-reflective, pre-linguistic, pre-narrative) given of some sort, one that is shared not merely by self-conscious adult human beings but also by animals, children and the cognitively impaired; on this view, selfhood in this more restricted sense is a necessary precursor of, but not coextensive with, personhood, which requires in addition some form of higher-order cognition or reflection.
The non-commutative nth-Chern number (n ⩾ 1)

The theory of the higher Chern numbers in the presence of strong disorder is developed. Sharp quantization and homotopy invariance conditions are provided. The relevance of the result to the field of strongly disordered topological insulators is discussed.
Impedance Methods for Analyzing Stability Impacts of Inverter-Based Resources: Stability Analysis Tools for Modern Power Systems

Power systems around the world are undergoing a major transformation because of the increasing shares of renewable energy, growing deployment of energy storage systems, proliferation of distributed energy resources, electrification of other sectors, and so on. In the United States, wind and solar provided almost 10% of electricity in 2019. The U.S. Energy Information Administration, in its 2020 Annual Energy Outlook, forecasted that the share of electricity from renewables will reach 38% by 2050, of which more than 80% will come from wind and solar. Wind and solar, along with battery energy storage systems, interface with the grid using power electronic inverters; hence, they are collectively referred to as inverter-based resources (IBRs). The increasing annual share of electricity from IBRs in a power system means that during more times of the year, the system will operate at a much higher concentration of IBRs. Figure 1 presents the hourly share of wind and solar generation in the Electric Reliability Council of Texas (ERCOT) system in Texas in 2019. While the annual wind share was at 20%, the instantaneous percentage share was much higher. Moments of high shares of IBRs (g50%) will continue to grow as more IBRs will be deployed in a power system.
The influence of range hood exhaust orientation on capture efficiency

In this study a test procedure for determining capture efficiency (CE) of domestic range hoods, namely ASTM-E3087.18, was used to investigate how changing the exhaust orientation of residential ran...
Designer Nanomaterials through Programmable Assembly.

Nanoparticles have long been recognized for their unique properties arising from their nanoscale morphology. While these phenomena offer exciting potential applications across optics, electronics, magnetism, and catalysis, these specific functions often require a designed organization of particles. This organizational control includes the type of order as well as placement and orientation of particles of the same or different kinds relative to each other. Although self-assembly processes can lead to a plethora of structures, the key aspect of rational material fabrication-designability-is difficult to achieve. DNA nanotechnology offers the ability to introduce highly addressable bonds, tailor particle interactions, and control the geometry of bindings motifs. Together, these features uniquely position DNA-based methods to tackle the problem of building fully designed nanomaterials. Here, we discuss how developments in structural DNA nanotechnology have enabled greater control over 1D, 2D, and 3D particle organizations through programmable assembly. This review focuses on how the use of DNA binding between nano-components and DNA structural motifs has progressively allowed rational formation of prescribed particle organizations. We offer insight into how DNA-based motifs and elements can be further developed to control particle organizations and how particles and DNA can be integrated into nanoscale building blocks, so called 'material voxels', to realize designer nanomaterials with desired functions.
Terawatt attosecond x-ray source driven by a plasma accelerator

Plasma accelerators can generate ultra-high-brightness electron beams that open the door to light sources with a smaller physical footprint and properties un-achievable with conventional accelerator technology. In this paper, we show that electron beams from Plasma WakeField Accelerators can generate few-cycle coherent tunable soft x-ray pulses with TW peak power and a duration of tens of attoseconds, an order of magnitude more powerful, shorter, and with better stability than state-of-the-art X-ray Free Electron Lasers (XFELs). Such a light source would significantly enhance the ability to experimentally investigate electron dynamics on ultrafast timescales, having a broad-ranging impact across multiple scientific fields. Rather than starting from noise as in typical XFELs, the x-ray emission in this approach is driven by coherent radiation from a pre-bunched, high peak current electron beam of attosecond duration. This relaxes the restrictive tolerances that have hindered progress toward utilizing plasma accelerators as coherent x-ray drivers thus far, presenting a new paradigm for advanced accelerator light source applications.
Design of a computer controlled manipulator for robot research

The purpose of this paper is to describe the Jet Propulsion Laboratory Robot Research Project's manipulator, including the rationale behind the design and the detailed design trade-offs that were made. It is intended to assist other workers in Artificial Intelligence (AI) who need to develop manipulators for their own use. A discussion is presented of the constraints and requirements imposed on the manipulator which led to the basic design, which was developed by Stanford University's Artificial Intelligence Project. Further, detail is presented on the implementation of the basic configuration. The end result is a manipulator which reproduces the flexibility and speed of a human arm. The manipulator is designed to be integrated with a vehicle and is completely computer controlled. Human commands are injected only at the gross instruction level, with a digital computer generating the control level commands. The JPL requirements are for the manipulator to pick up irregular objects from the laboratory working area, or surface, and move them to an arbitrary position either on or off the vehicle, while avoiding any obstacles. The manipulator (Fig.1) has 6 degrees of freedom which allow the grasping device (hand) to be placed in any a rbitrary position with great flexibility. The joints from the base to the hand consist of two rotary joints, one linear joint and three rotary joints (2R, 1L, 3R using the nomenclature of Ref. 1). This allows the human waist, shoulder, arm and wrist motions to be reproduced. Manipulator reach is a maximum of 52" and an object of about 5 pounds may be lifted. The manipulator may reach an object in any part of a sphere that is not occupied (i.e., by the vehicle, floor, etc.). System response allows a maximum motion to be accomplished in about 5 seconds. Power is supplied by 6 permanent magnet DC torque motors geared directly to each link. For the first four inner rotary joints, harmonic drive gearing is used, with rack and pinion drive for the linear joint. For the outer rotary joint, spur gearing is used. DC power is provided through analog DC amplifiers to minimize electrical noise. Analog position and rate feedback information is provided. Brakes are used in each joint to provide holding torque.
Influence of Three Dimensional Effects on the Stress Intensity Factor for Compact Tension Specimens.

Abstract : The stress freezing technique of photoelasticity was utilized to study the stress intensity variation between full thickness and center slices of compact tension specimens for various crack lengths. Specimen geometries covered an a/w range of 0.3 to 0.7 and for values of w/B of 2 and 3.5 Normalized SIF results for geometries within ASTM E 399-72 specifications (i.e. w/B = 2.0, a/w = 0.50) agreed with the ASTM solution to within experimental error. However, for a/w values outside the ASTM range (0.45 to 0.55), experimental results were measurably higher than the ASTM results for w/B = 2.0 and averaged 13% higher for all a/w studied at w/B 3.5. The center slice SIF was found to be 5 to 10% higher than the through the thickness average on all tests. (AN)
Solubilization and Partial Purification of Protein Methylase III from Calf Thymus Nuclei

Abstract An enzyme which methylates the e-amino group of lysine residues in histones was solubilized from calf thymus nuclei. The enzyme was present in nuclei and was found in all the rat organs tested. Although the enzyme was not purified to high extent, practically all of the endogenous methylation activity (enzyme activity without added exogenous histone) was eliminated. The enzyme was most effective toward various histones, and especially arginine-rich histone. Polylysine was methylated to some extent. Zinc ion at a concentration of 2 x 10-3 m abolished the enzyme activity completely, but Mg++ ions were without effect. The Km value of the enzyme for S-adenosyl-l-methionine was 3.0 x 10-6 m. A simple assay method for the enzyme activity was also determined.
Crowd Work and Collective Learning

The process of assembling crowds to perform tasks constitutes a new form of work practice. The current practice forms a basis for future instructional and organisational design activity, providing opportunities for improvement in both individual and collective learning. In particular, feedback systems – from other crowd workers, from experts, and from computers – play a role in improving individual learning and performance. More generally, standardisation in this emerging industry may increase the portability of skills and create career ladders, important to both workers and employers.
Scope for process systems engineering studies in proton exchange membrane fuel cells (PEMFC): A review of opportunities

Publisher Summary Outlining the scope for process systems engineering studies in proton exchange membrane fuel cells (PEMFC), this chapter presents a review of opportunities. Proton exchange membrane fuel cells PEMFCs are currently in an advanced state of development with promising applications for portable power and power generation. In spite of this, even today, there are several critical issues that researchers are trying to address and resolve. This chapter highlights some of the important technological advancements made in the areas of (i) flow field design and (ii) water and thermal management. A review of the state-of-art in engineering and design in each of these areas are also summarized in the chapter. At the same time, it also highlight the areas where opportunities exist for process systems engineering activities such as, modeling and simulation, optimization, control, diagnostics, and fault-tolerant control. The focus of the research work being discussed in this article is the systems engineering of PEMFC with the help of both detailed models and reduced order models.
Akbulut's corks and h-cobordisms of smooth simply connected 4-manifolds

This is primarily an exposition, combining work of several authors (Curtis, Hsiang, Freedman, Stong, Matveyev, and Bizaca), of the proof that a smooth 5-dimensional h-cobordism between simply connected 4-manifolds is a product off of a contractible piece which itself is diffeomorphic to the 5-ball.
A differential equation approach for the analysis of the adaptive lattice filter

The convergence properties of an adaptive lattice filter using a stochastic gradient algorithm are investigated using differential equations. The mean of the PARCOR coefficients of the adaptive lattice filter is obtained by analyzing an associated ordinary differential equation (ODE). An efficient way to compute the statistics required for the solution of the ODE is presented. An expression for the variance of the PARCOR coefficients is derived from the stochastic differential equation (SDE) associated with the normalized error process. Simulation results are given to support the theoretical results. >
Unique two-cell co-culture assays show mutual dependence of macrophages and breast cancer cells in invasion

Proc Amer Assoc Cancer Res, Volume 45, 2004 1765 One of the key steps in the metastatic spread of tumors is the invasion of tumor cells into the surrounding connective tissue and blood vessels. The presence of increasing numbers of macrophages in primary tumors has been shown to correlate with poor prognosis. The possible mechanism supporting this observation was not available until recently, when a paracrine loop was proposed between the tumor cells and the macrophages mediated by the growth factors Epidermal growth factor (EGF) and Colony stimulating factor-1 (CSF-1). EGF was shown to be synthesized by macrophages and CSF1 by carcinoma cells in tumors exhibiting the paracrine interaction between these cell types. In order to further elucidate the paracrine loop we have reconstituted the paracrine loop in vitro. In a 2D assay, carcinoma cells (MTLn3) and macrophages (BAC) were co-cultured on glass and they exhibit polarization towards each other when stimulated with CSF-1. The effect is dependent on the activation of EGF receptors as evident by the absence polarization in the presence of EGFR blocking drugs. The mechanism of this polarization is being studied. In a 3D assay, these cells are co-cultured on glass and allowed to invade an overlaid collagen matrix. In this assay, optimum invasion occurs only in the presence of both cell types and requires CSF1, and EGF-R function. RTPCR demonstrates the expression of EGFR and CSF-1 message in the carcinoma cells and EGF and Colony stimulating factor-1 receptor message in the macrophages. Taken together these results along with the evidence published before by our group, indicate that the carcinoma cells and macrophages interact closely in a paracrine loop augmenting invasion and possibly intravasation and metastasis.
Homogenization technique of discrete atoms into smeared continuum

A homogenization technique was developed and presented to replace a discrete atomic domain by an equivalent continuum domain that could be discretized into finite elements. Equivalent material properties of the smeared continuum domain were computed from the atomic model. Using the developed technique, a computationally efficient analysis could be performed for a large size of domain by proper mixture of a discrete atomic region and a smeared continuum region. In addition, this technique provided a means for multi-scale analysis. Examples for static and dynamic analyses were provided to demonstrate the technique.
3-D reconstruction of the coronary artery tree from multiple views of a rotational X-ray angiography

To present an efficient and robust method for 3-D reconstruction of the coronary artery tree from multiple ECG-gated views of an X-ray angiography. 2-D coronary artery centerlines are extracted automatically from X-ray projection images using an enhanced multi-scale analysis. For the difficult data with low vessel contrast, a semi-automatic tool based on fast marching method is implemented to allow manual correction of automatically-extracted 2-D centerlines. First, we formulate the 3-D symbolic reconstruction of coronary arteries from multiple views as an energy minimization problem incorporating a soft epipolar line constraint and a smoothness term evaluated in 3-D. The proposed formulation results in the robustness of the reconstruction to the imperfectness in 2-D centerline extraction, as well as the reconstructed coronary artery tree being inherently smooth in 3-D. We further propose to solve the energy minimization problem using α-expansion moves of Graph Cuts, a powerful optimization technique that yields a local minimum in a strong sense at a relatively low computational complexity. We show experimental results on a synthetic coronary phantom, a porcine data set and 11 patient data sets. For the coronary phantom, results obtained using different number of views are presented. 3-D reconstruction error evaluated by the mean plus one standard deviation is below one millimeter when 4 or more views are used. For real data, reconstruction using 4 to 5 views and 256 depth labels averaged around 12 s on a computer with 2.13 GHz Intel Pentium M and achieves a mean 2-D back-projection error of 1.18 mm (ranging from 0.84 to 1.71 mm) in 12 cases. The accuracy for multi-view reconstruction of the coronary artery tree as reported from the phantom and patient studies is promising, and the efficiency is significantly improved compared to other approaches reported in the literature, which range from a few to tens of minutes. Visually good and smooth reconstruction is demonstrated.
Purification of Crotonyl‐CoA Reductase from Streptomyces collinus and Cloning, Sequencing and Expression of the Corresponding Gene in Escherichia coli

A crotonyl-CoA reductase (EC 1.3.1.38, acyl-CoA:NADP+trans -2-oxidoreductase) catalyzing the conversion of crotonyl-CoA to butyryl-CoA has been purified and characterized from Streptomyces collinus. This enzyme, a dimer with subunits of identical mass (48 kDa), exhibits a Km, = 18 μM for crotonyl-CoA and 15 μM for NADPH. The enzyme was unable to catalyze the reduction of any other enoyl-CoA thioesters or to utilize NADH as an electron donor. A highly effective inhibition by straight-chain fatty acids (Ki=9.5 μM for palmitoyl-CoA) compared with branched-chain fatty acids (Ki>400 μM for isopalmitoyl-CoA) was observed. All of these properties are consistent with a proposed role of the enzyme in providing butyryl-CoA as a starter unit for straight-chain fatty acid biosynthesis. The crotonyl-CoA reductase gene was cloned in Escherichia coli. This gene, with a proposed designation of ccr, is encoded in a 1344-bp open reading frame which predicts a primary translation product of 448 amino acids with a calculated molecular mass of 49.4 kDa. Several dispersed regions of highly significant sequence similarity were noted between the deduced amino acid sequence and various alcohol dehydrogenases and fatty acid synthases, including one region that contains a putative NADPH binding site. The ccr gene product was expressed in E. coli and the induced crotonyl-CoA reductase was purified tenfold and shown to have similar steady-state kinetics and electrophoretic mobility on sodium dodecyl sulfate/polyacrylamide to the native protein.
Uniqueness of Lipschitz extensions: Minimizing the sup norm of the gradient

In this paper we examine the problem of minimizing the sup norm of the gradient of a function with prescribed boundary values. Geometrically, this can be interpreted as finding a minimal Lipschitz extension. Due to the weak convexity of the functional associated to this problem, solutions are generally nonunique. By adopting G. Aronsson's notion of absolutely minimizing we are able to prove uniqueness by characterizing minimizers as the unique solutions of an associated partial differential equation. In fact, we actually prove a weak maximum principle for this partial differential equation, which in some sense is the Euler equation for the minimization problem. This is significantly difficult because the partial differential equation is both fully nonlinear and has very degenerate ellipticity. To overcome this difficulty we use the weak solutions of M. G. Crandall and P.-L. Lions, also known as viscosity solutions, in conjunction with some arguments using integration by parts.
Toeplitz Operators and Hankel Operators on the Hardy Space of the Unit Sphere

Abstract A sufficient condition is found for the product of two Toeplitz operators on the Hardy space of the unit sphere to be a compact perturbation of a Toeplitz operator. The condition leads to a criterion for a Hankel operator to be compact.
Interaction of Iron and Calcium Minerals in Coals and their Roles in Coal Dust-Induced Health and Environmental Problems

Epidemiological studies using pollutant gases (e.g., SO2) and particle characteristics (e.g., elemental carbon) indicate that products of fossil fuel combustion are important contributors to particulate matter (PM)-associated hospital admissions and mortality. Coal is one of the world’s most important fossil fuels, providing 40% of electricity worldwide. Besides individuals exposed to PM in ambient air, coal mining can cause adverse health effects in workers exposed to coal dusts at the workplace. Among the respiratory diseases, coal workers’ pneumoconiosis (CWP) has received the most attention because of its clear occupational association. The field of CWP research is one of the few areas in occupational health in which considerable epidemiological data are available. This offers a good opportunity to focus on the relationship between epidemiological data and physico-chemical and/or biological characteristics of coals. The objective of this review is to assess whether some physico-chemical parameters play a role in the observed regional differences in the prevalence of CWP among various coalmine regions. We mainly concentrate on the chemical interaction of two minerals, pyrite (FeS2) and calcite (CaCO3) in the coals and their role in causing occupational lung diseases (e.g., pneumoconiosis) and other environmental problems (e.g., acid mine drainage). Therefore, understanding the chemical interaction of the two minerals in the coal may lead to the identification of the causal components in coal dusts as well as in PM. Examples from U.S.A. coals are used to illustrate the chemical interaction and geological distribution of iron and calcium minerals in various coalmine regions and how the differences in levels of these types of minerals contribute to the observed regional differences in the prevalence of CWP. Molecular mechanisms leading to the CWP development are also discussed, particular in the aspects of oxidative stress and inflammation.
Characteristics of Prison Hospice Programs in the United States

Hospice programs have emerged over the last 40 years as both an effective and humane practice for responding to terminal illnesses in the free society. More recently, hospice has diffused throughout state, federal, and municipal correctional systems. Thus, we sought via a mailed survey of the 69 known prison hospice programs in the United States (response rate of 62%) to determine how prison hospice programs were similar or dissimilar to hospices in the free society. Our findings suggest that prison hospices have a more stringent screening process for volunteers and require more volunteer training prior to interacting with a hospice patient. Prison hospice programs tend to follow both the National Prison Hospice Association and the GRACE Project guidelines.
Incentives for microgeneration development in the U.S. and Europe

The growth of commercial and residential renewable energy generation systems is contingent upon the government providing incentives to make their investments profitable. In this regard, countries have different approaches to promote the expansion of microgeneration in their nations. This paper provides an overview on policies that individual states in the U.S. and countries in Europe have developed. This may facilitate current and future policy revisions considering the experience of other nations in promoting microgeneration.
Identification of Components in Iodinated Glycerol

Iodinated glycerol (CAS no. 5634-39-9), therapeutically used as an expectorant and source of organically bound iodine, was analyzed to determine the purity and composition of the chemical samples used in carcinogenicity and toxicity studies. The manufactured product is described by the patent and chemical literature as a mixture of two isomeric iodopropylideneglycerols (structures 1 and 2). The results of our studies, however, indicate that the two principal components of the product were 3-iodo-1,2-propanediol (IPD) and glycerol (GLY). Analyses from GC-MS (full scan electron impact) and carbon-13 nuclear magnetic resonance spectrometry provided conclusive identification of these components. The quantification of IPD and GLY in one of two samples of commercial product using GC-flame ionization detection indicated concentrations of 33 and 17%, respectively (Sample A). Similar concentrations were determined for a second sample from the same source (Sample B), which was a gratis sample procured approximately nine years after Sample A. Numerous minor components were also observed in these two samples. These components were tentatively identified as condensation products of glycerol and iodine-containing analogues. The iodopropylideneglycerol compounds, described in the patent, were not observed in either of the two samples.
Circuit models of stochastic genetic networks

We use analogies between chemistry and subthreshold electronics to develop fast, scalable, digitally programmable hardware models of stochastic genetic networks. We also present experimental results from a prototype 0.18µm CMOS chip that was designed for rapid simulations of gene activation, transcription and translation.
An Analysis of Academic Research Libraries Assessment Data: A Look at Professional Models and Benchmarking Data

Abstract This research provides the first review of publicly available assessment information found on Association of Research Libraries (ARL) members' websites. After providing an overarching review of benchmarking assessment data, and of professionally recommended assessment models, this paper examines if libraries contextualized their assessment activities for planning internal program improvements. Benchmarking data included LibQUAL + ® and SAILS. Professionally recommended assessment models included Return on Investment and the value-added framework. This research analyzes ARL members' annual reports, websites, and strategic plans to evaluate whether or not libraries used benchmarking assessment and endorsed assessment models to describe their value to the parent institution. The results of this research reveal inconsistencies among ARL members' reporting of assessment. The researchers offer examples of exemplary assessment reporting by three ARL members.
Cloning and expression of a new pregnancy-specific β1-glycoprotein member

Abstract Human pregnancy-specific β1-glycoproteins (PSGs) are a group of closely related placental glycoproteins and members of the immunoglobulin superfamily. To study possible functional roles of PSG, three type I cDNA ciones which encode PSG in a N-A1-A2-B2-C domain arrangement have been characterized in this laboratory. Now, we report the cloning of a type II cDNA (PSG9) which is 1512 bp and encodes a PSG of 332 amino acids in a N-A1-B2-C domain arrangement. In vitro expression experiments demonstrate that PSG9 encodes a 36 kDa nonglycosylated protein which is processed to a glycosylated protein of 46 kDa. Ribonuclease protection analyses show that PSG mRNAs that share sequence similarity with the PSG9 transcript are expressed in both human placenta and placental fibroblasts.
Interfaces with controlled toughness as mechanical fuses to isolate fibres from damage

A source of inadequate performance of metal matrix composites has been the loss of strength due to the reaction layers between the fibre and the surrounding metal matrix. Here, we propose that the traditional diffusion barrier coatings on the fibre can be utilized to serve as mechanical fuses to isolate the impinging reaction zone cracks by interface delamination. Requirements on the interface strength and toughness for the specific tailoring of the fibre-coating interface are given. Special problems associated with the graphite-aluminium system are identified. A double cantilever beam experiment has been developed to measure the work of separation of thin coatings (0.1 to 0.3 μm) from bulk substrates. This test has been successfully applied to measure the work of fracture of the interface between a planar pyrolytic graphite substrate with the same chemistry and closely related microstructure as that of the 10 μm Pitch-55 graphite fibre and SiC coatings on them. A value of 60 J m−2 was obtained for the critical energy release rate for the PG-SiC interface. Additional measurements of energy release rates in thin layers of glue used to model the aluminium matrix and in PG itself, have given values which account for the high toughness of the main interfaces through the accompanying inelastic deformation work in the glue and the PG while the crack travels along the interface.
Weak Foundations: The Economy of El Salvador in the Nineteenth Century

Weak Foundations: The Economy of El Salvador in the Nineteenth Century. Hector Lindo-Fuentes Berkeley: University of California Press, 1990. 239 pp. $34.95 (cloth). ISBN 0520–069277.
Modeling for insights, not numbers: the experiences of the energy modeling forum

It has often been contended that the primary goal of policy modeling should be the insights quantitative models can provide, not the precise-looking projections—i.e. numbers—they can produce for any given scenario. Students of the energy policy process, in particular, have noted that preoccupation with the plethora of detailed quantitative results produced by large-scale computer models has substantially impeded their influence on key policy decisions. The creation of the Energy Modeling Forum (EMF) at Stanford University in 1976 represents one potential remedy for that situation. The EMF was formed to foster better communication between the builders and users of energy models in energy planning and policy analysis. The EMF operates through ad hoc working groups, composed of national and, more recently, international energy modeling and policy experts. These working groups conduct studies concentrating on a single energy topic. The diversity of backgrounds of the working group members ensures that the language of the EMF studies is English, not computer. Each working group identifies existing models relevant to the study's focus. A series of tests is then designed by the group to illuminate the models' basic structure and behavior. A comparison of results is published in a widely distributed report that identifies the models' strengths and weaknesses in the context of the study's topic. Seven EMF studies have been initiated to date: (1) Energy and the economy, (2) Coal in transition, (3) Electric load forecasting, (4) Aggregate elasticity of energy demand, (5) US oil and gas supply, (6) World oil and (7) Macroeconomic impacts of energy shocks. Each EMF study has broadened the understanding of the nature of the relevant policy issues and the models that have been, are, or could be used to address them. The present paper describes how each study's key insights were developed in the context of a simplified analytical framework that provided the proper perspective for understanding the model results.
Synthesis, Structures, and Reactivity of Bis(dithiolene)molybdenum(IV,VI) Complexes Related to the Active Sites of Molybdoenzymes

The existence of a universal pterin dithiolene cofactor ligand for the molybdenum and tungsten oxotransferases supports a biological significance of the fundamental chemistry of mono- and bis(dithiolene) complexes of these elements. Members of the dimethyl sulfoxide (DMSO) reductase family of enzymes contain two pterin dithiolene ligands; at least one enzyme functions by using the minimal reaction couple MoIV + Me2SO ⇄ MoVIO + Me2S. Accordingly, the synthesis, structures, and reactivity of bis(dithiolene)Mo(IV,VI) complexes of benzene-1,2-dithiolate and related ligands have been investigated. A convenient synthesis of square pyramidal [MoIVO(S2C2R2)2]2- complexes is reported. Compounds of the type [Mo(S2C2R2)2(R‘NC)2], including [Mo(bdt)2(MeNC)2] (13), were prepared by reacting Na2(S2C2R2) and R‘NC with [MoCl4(MeCN)2] and were shown to be identical (R‘ = Me) to byproducts in the synthesis of [MoIVO(S2C2R2)2]2-. In one such reaction, the Fischer carbene complex [Mo(Me4bdt)2(MeNC)(CMe4bdt)] (16) was isolate...
Drug-induced gastrointestinal disease.

The gastrointestinal tract is a common target for adverse drug reactions. The resultant changes are often nonspecific (e.g., mucosal ulceration, intestinal infarction, motility disturbance) and in many cases no radiographically detectable lesion may occur. A comprehensive review of the reported drug-induced disorders of the digestive organs is herein presented and their radiographic manifestations are described.
A peculiar presentation of a large retrocardiac mass.

![Figure][1] [![Graphic][3] ][3] A 13-year-old young man with anxiety presented for echocardiogram after multiple emergency room visitations for atypical chest pain. An echocardiogram (A to E) displayed a fluid filled, tube-like structure posterior to the left atrium (LA) and parallel
Nanosecond-Pulsed Discharge Plasma Splitting of Carbon Dioxide

This paper reports on the study of repetitive nanosecond-pulsed discharge splitting of carbon dioxide (CO2) for the production of CO. Gas chromatography is used to analyze the composition of the reformed gas when CO2 is exposed to high-voltage (15 kV) very short (10 ns) electrical discharges that deposit as much as 0.4 mJ of energy at a rate of 30 kHz. Conversion rate and energy efficiency are obtained while the discharge pressure is varied between 2.4 and 5.1 atm. At the tested conditions, the maximum conversion rate and energy efficiency are found to be 7.3% and 11.5%, respectively. The energy efficiency drops slightly with increased pressure because of the decreased electric field and electron energy per molecule. An energy balance analysis of a set of CO2 plasma reactions reveals that the dominant dissociation pathway under these conditions passes through the excitation of CO2 (10.5 eV) followed by autodissociation into CO and O, which are often in excited states.
CORRELATES AND FITNESS CONSEQUENCES OF NATAL DISPERSAL IN SWAINSON'S HAWKS

Abstract. Natal dispersal is an important, yet often poorly studied, process in population ecology. Natal dispersal can affect population structure and individual fitness. We examined correlates of natal dispersal distances of a population of Swainson's Hawk (Buteo swainsoni) in northern California that has been monitored from 1979 to 2010. We examined the effects of sex, number of offspring fledged, population density, primary productivity around a nest site, and annual trends on dispersal from the natal site to the breeding site of individuals recruited into the breeding population. Female Swainson's Hawks dispersed farther than males. Natal dispersal was negatively correlated with primary productivity and was positively correlated with population density around the nest site. We found no correlation between natal dispersal distance and lifetime reproductive success of those individuals recruited into the breeding population, indicating no fitness costs of increased dispersal. We examined the potential ...
Organically modified silica nanoparticles as drug delivery vehicles in photodynamic therapy

To investigate the effect of hydrophobicity, charge and size of photosensitizers (PS) on their encapsulation efficiency in organically modified silica nanoparticles (ORMOSIL), a series of alkyl ether analogs of 2-(1′-hexyloxyethyl)-2-devinyl pyropheophorbide-a (HPPH) containing varied number of carbon units, HPPH with anionic and cationic functionalities, and HPPH analogs with molecular weight ranging from ~630 to 6000 Daltons were synthesized. Our preliminary results suggest that these factors play a significant role in encapsulation of the photosensitizers and their release from ORMOSIL nanoparticles. The synthesis and characterization of PS-encapsulated ORMOSIL and a comparative study on the effect of PS size, lipophilicity and charge on encapsulation efficiency, photophysical characteristics and release kinetics are discussed.
Modification of rat operant behavior by ozone exposure

Abstract Ozone exposure may induce extrapulmonary consequences, such as reductions in the spontaneous activity of rodents, or complaints in humans of lethargy, headache, chest discomfort, and other subjective symptoms. Further evidence of behavioral disruption was provided by this experiment. Twelve rats were trained to perform a bar-pressing response maintained by food reward. Food pellets were delivered according to a fixed interval 5-min reinforcement schedule. Exposures encompassed a range of concentrations from 0.1 to 2.0 ppm. A single exposure lasted 6 hr, and successive exposures were separated by at least 6 days. Compared to performance under control conditions (ambient air), response rates fell linearly from 0.1 to 1.4 ppm. During individual 6-hr exposures, the rates declined from the beginning to the end of the session. These results, given the sedentary nature of the task, reflect reduced inclination rather than impaired physiological capacity to respond.
A technique for calculating the mean time for equilibration of drug distribution using minimal structural assumptions

Disposition decomposition analysis is used as a framework to derive a parameter for the description of drug distribution kinetics. This parameter, denotedtd, is a measure of the mean time for equilibration of distribution in the absence of metabolic drug elimination. The derivation requires only the assumption that distribution is linear, and is generally valid as long as any nonlinearity is due to central nonlinear elimination. The mean time for equilibration of distribution,td, is evaluated in terms of the moments of the distribution function,h(t), derived by disposition decomposition analysis. Estimates oftd for several drugs are presented.
Inductance cardiography (thoracocardiography): a novel, noninvasive technique for monitoring left ventricular filling.

Abstract Purpose: Thoracocardiography noninvasively records left ventricular volume curves by an inductive plethysmographic transducer transversely encircling the chest near the xiphoid process. Amplitudes of thoracocardiographic curves track stroke volume as previously validated by thermodilution. We investigated whether thoracocardiographic curves reflect left ventricular filling. Materials and Methods: We studied nine men in horizontal and 30° head-up position during tidal breathing and Valsalva maneuvers. The ratio of peak slope of left ventricular volume curves during early rapid filling relative to that during atrial contraction (E/A ratio) and isovolumic relaxation time(interval from aortic component of second heart sound to early rapid filling onset) were measured with thoracocardiography and compared with Doppler-echocardiographic-derived indices of transmitral flow velocity. Results: Isovolumic relaxation times estimated by the two methods agreed closely (bias = -2 ms, limits of agreement = -28 to +24 ms, 75 comparisons). E/A ratios by thoracocardiography and Doppler echocardiography were significantly correlated (R = 0.53, n = 75, P Conclusions: Thoracocardiography reflects characteristics of left ventricular filling similarto Doppler echocardiography. Because it does not require hand-holding a transducer, thoracocardiography has the potential for continuous monitoring of mechanical cardiac performance.
Effects of creatine supplementation and three days of resistance training on muscle strength, power output, and neuromuscular function.

Previous studies have demonstrated increases in peak torque (PT) and decreases in acceleration time (ACC) after only 2 days of resistance training, and other studies have reported improvements in isokinetic performance after 5 days of creatine supplementation. Consequently, there may be a combined benefit of creatine supplementation and short-term resistance training for eliciting rapid increases in muscle strength, which may be important for short-term rehabilitation and return-to-play for previously injured athletes. The purpose of this study, therefore, was to examine the effects of 3 days of isokinetic resistance training combined with 8 days of creatine monohydrate supplementation on PT, mean power output (MP), ACC, surface electromyography (EMG), and mechanomyography (MMG) of the vastus lateralis muscle during maximal concentric isokinetic leg extension muscle actions. Twenty-five men (mean age +/- SD = 21 +/- 3 years, stature = 177 +/- 6 cm, and body mass = 80 +/- 12 kg) volunteered to participate in this 9-day, double-blind, placebo-controlled study and were randomly assigned to either the creatine (CRE; n = 13) or placebo (PLA; n = 12) group. The CRE group ingested the treatment drink (280 kcal; 68 g carbohydrate; 10.5 g creatine), whereas the PLA group received an isocaloric placebo (70 g carbohydrate). Two servings per day (morning and afternoon) were administered in the laboratory on days 1-6, with only 1 serving on days 7-8. Before (pre; day 1) and after (post; day 9) the resistance training, maximal voluntary concentric isokinetic leg extensions at 30, 150, and 270 degrees x s(-1) were performed on a calibrated Biodex System 3 dynamometer. Three sets of 10 repetitions at 150 degrees x s(-1) were performed on days 3, 5, and 7. Peak torque increased (p = 0.005; eta(2) = 0.296), whereas ACC decreased (p 0.05). There were no changes in MP, EMG, or MMG amplitude; however, EMG median frequency (MDF) increased, and MMG MDF increased at 30 degrees x s(-1), from pretraining to posttraining for both the CRE and PLA groups. These results indicated that 3 days of isokinetic resistance training was sufficient to elicit small, but significant, improvements in peak strength (PT) and ACC for both the CRE and PLA groups. Although the greater relative improvements in PT and ACC for the CRE group were not statistically significant, these findings may be useful for rehabilitation or strength and conditioning professionals who may need to rapidly increase the strength of a patient or athlete within 9 days.
Computational solution of the defect stream-function equation for nonequilibrium turbulent boundary layers

The derivation of the accurate, second-order, almost linear, approximate equation governing the defect stream function for nonequilibrium compressible turbulent boundary layers is reviewed. The similarity of this equation to the heat conduction equation is exploited in the development of an unconditionally stable, tridiagonal computational method which is second-order accurate in the marching direction and fourth-order accurate in the surface-normal direction. Results compare well with experimental data. Nonlinear effects are shown to be small. This two-dimensional method is simple and has been implemented on a programmable calculator.