cssi/SciSciGPT-SciSciNet huggingface dataset:
Have Randomized Controlled Trials of Neuroprotective Drugs Been Underpowered?: An Illustration of Three Statistical Principles

Background and Purpose —The results of phase III trials of neuroprotective drugs for acute ischemic stroke have been disappointing. We examine the question of whether these trials may have been underpowered. Methods —Computer simulations were based on the binomial distribution. Results —We illustrate that even small overestimates of the efficacy of an intervention can lead to a serious reduction in statistical power, that the use of data from phase II studies tends to lead to such overestimation, and that a minimum clinically important difference derived with cost-effectiveness modeling techniques is considerably smaller than might be suggested by intuition. Conclusions —We recommend placing more emphasis on minimum clinically important differences when planning stroke trials, with these differences being derived from an assessment of the public health impact obtained in conjunction with the use of epidemiological and cost-effectiveness models. Even small benefits, when averaged over a sufficiently large number of cases, will, in total, accrue to a large positive impact on the public health.
School Counselor Inclusion: A Collaborative Model to Provide Academic and Social‐Emotional Support in the Classroom Setting

The increasingly diverse student demographics reflect a myriad of needs in the interrelated arenas of educational achievement, social-behavioral adjustment, and career development, while federal legislation, the ethical standards of the American School Counselor Association (ASCA; 2004a), and the ASCA (2005a) National Model have emphasized academic achievement and success for all students. This article describes a new model of school counselor “inclusion” that involves collaboration with classroom teachers and changes the setting of school counselor interventions to the classroom for small-group and individual work.
Statistical analysis on the effect of capacitance mismatch in a high-resolution successive-approximation ADC

This paper describes the statistical analysis of the effect of capacitance mismatch on the accuracy of a high-resolution successive-approximation analog-to-digital converter (ADC), which employs a split capacitor array to achieve high resolution. An analysis has been made for the following two types of capacitor digital-to-analog converters (DACs). One is the capacitor DAC with binary-weighted capacitor array. The other is that which uses the segmented capacitor array for the upper bits to relax the matching requirement. The analysis was verified using the Monte-Carlo simulation with capacitance mismatch. This analysis clarifies the required capacitance matching for a given ADC resolution and provides with a guideline for the optimum design. © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Manifestation of Hybrid Vigor in RNA Synthesis Parameters by Corn Seedling Protoplasts in the Presence and Absence of Gibberellic Acid

Summary We have investigated several parameters of RNA synthesis in seedling protoplasts of a heterotic maize hybrid and its inbred parents in the presence and absence of the transcription-stimulating phytohormone gibberellic acid (GA 3 ). In the absence of GA 3 , seedling protoplasts of the three genotypes differ in kinetics of [ 3 H] uridine incorporation into acid-insoluble material, total amount of label incorporated into RNA after 6 h of incubation, and the content of poly(A) + RNA. Protoplasts from hybrid plants synthesize a greater amount of poly(A) + RNA than protoplasts of the inbred parents. In the presence of GA 3 at a concentration of 10 −7 M, protoplasts from hybrid plants exhibit a superior response to hormone in both the initial rate of [ 3 H]uridine incorporation into acid-insoluble material and the percentage increase in poly(A) + RNA content. The significance of these data to an understanding of the role of RNA metabolism in the generation of hybrid vigor is discussed.
The effect of varying carboxylate ligation on the electronic environment of N2Ox (x = 1–3) nonheme iron: A DFT analysis

Mononuclear nonheme iron oxygenase (MNO) enzymes contain a subclass of metalloproteins capable of catalyzing the O2-dependent hydroxylation of unactivated substrates at a ferrous ion center coordinated to a highly conserved His-His-Glu/Asp motif. These enzymes, which utilize additional reducing equivalents obtained from the decarboxylation of a coordinated α-ketoglutarate (αKG) cofactor, do not readily interact with O2 in the absence of αKG binding. Density functional theory calculations with the B3LYP functional were performed to gain insight into the electrochemical behavior of three sets of FeII/III complexes containing a core N, N, O facial binding motif in which the number of carboxylate ligands was systematically altered, to provide one, two (cis) or three (fac) labile sites. The calculated trend in FeII/IIIreduction potentials was observed to parallel that observed in cyclic voltammetry experiments, showing a decrease in potential (stabilized oxidized state) with increasing carboxylate ligation. This trend does not appear to be the result of differential charge on the metal complex. Changes in the redox-active molecular orbital (RAMO) energy due to covalent effects dominate across the series of complexes when chloride is modeled as the labile ligand, with the π anti-bonding nature of the RAMO being an important factor. With water molecules as the labile ligands, however, a much steeper redox dependence on the number of carboxylate ligands is observed and this effect seems to be largely electrostatic in origin. Differential relaxation of the occupied molecular orbitals in the ferric complexes appears to contribute to the redox trend as well. Finally, these observations are placed in the context of MNO enzyme mechanisms.
Magnetocrystalline Anisotropy of Single-Crystal Europium Oxide

The first-order cubic anisotropy constant ${K}_{1}$ in EuO single crystal was measured as a function of temperature and applied field by the static torque method. The value at $T=0\ifmmode^\circ\else\textdegree\fi{}$K is ${K}_{1}(0)=\ensuremath{-}(4.36\ifmmode\pm\else\textpm\fi{}0.1)\ifmmode\times\else\texttimes\fi{}{10}^{5}$ erg/${\mathrm{cm}}^{3}$. The variation of ${K}_{1}$ with $T$ and $H$ is uniquely described by the behavior of the measured magnetic moment $\ensuremath{\sigma}(H, T)$. The observed relationship between $\frac{{K}_{1}(H, T)}{{K}_{1}(0, 0)}$ and $\frac{\ensuremath{\sigma}(H, T)}{\ensuremath{\sigma}(0, 0)}$ is explained by a theory of single-ion interaction with the cubic crystal potential. The cubic crystal-field splitting parameter ${b}_{4}=(21.2\ifmmode\pm\else\textpm\fi{}0.5)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ ${\mathrm{cm}}^{\ensuremath{-}1}$/ion obtained from ${K}_{1}(0)$ is compared with results for ${\mathrm{Eu}}^{++}$ ions in various other materials.
Human-robot team dynamic performance in assisted living environments

In this work it is assumed that some interaction must occur when introducing robots into an environment for the purpose of assisting humans. This interaction may take several forms, but the one considered here is following, which means the robot(s) should follow the human. The robot should maintain some distance but keep him/her in its line of sight to prevent losing the target. In a human environment, this is a challenging task due to the corners or doorways that a human may disappear through or around. Here, the task of maintaining a line of sight to the human while turning a corner is modeled as a rotation of the human-robot team, in order to determine the performance requirements for the robots. The development of a description for a team rotation is the key element in the proposed work. The methodology is illustrated using omnidirectional robots with mass, inertia, and actuator limitations.
Double-resonance laser-induced grating spectroscopy of nitric oxide

Abstract Double-resonance laser-induced grating spectroscopy (LIGS), including two-color laser-induced grating spectroscopy (TC-LIGS) and degenerate four-wave mixing (DFWM) spectroscopy, has been used to probe the E 2Σ, ν=0←A 2Σ, ν′=0←X 2Π 1 2 , ν″=0 double-resonance transitions in NO. Several different double-resonance schemes have been implemented and their relative merits are discussed. The results demonstrate that double-resonance LIGS shows considerable promise for obtaining state-selective absorption spectra of rovibronically excited states for a wide variety of molecules.
Fasting ketosis in the adrenalectomized and cortisone-treated rat.

C concerning the role of the adrenal cortex in ketone metabolism have been colored by the universal finding that ketonuria during fasting or after phloridzin poisoning is essentially abolished by adrenalectomy. (Evans, 1936; MacKay and Barnes, 1937; MacKay and Wick, 1939; Samuels and Conant, 1944; Segaloff and Many, 1952). On the other hand when blood ketone levels have been measured in adrenalectomized animals values not grossly different from normal have been found frequently and it has become apparent that failure of renal excretion of ketone bodies is a large factor accounting for the absence of ketonuria after adrenalectomy (Mirsky, 1938; Shipley and Long, 1938; MacKay and Wick, 1939, MacKay et al, 1946; Banner 1953). Recently it has been reported from this laboratory (Scott and Engel, 1953) that both cortisone and hydrocortisone depress fasting and coldstress ketosis in the rat, a result consistent with the report of Kinsell et al. (1952) that ACTH and cortisone block fasting ketosis in man. This finding plus observations on the effect of changes in the circulation on fasting ketosis led us to reinvestigate the effect of adrenalectomy on fasting ketosis. It is well known that the circulation of the adrenalectomized rat not maintained with hormone is not up to par. In the normal rat depression of the circulation by a small hemorrhage inhibits fasting ketosis while frank hemorrhagic shock actually lowers blood ketone levels (Engel and Hewson, 1953). It seemed possible that enhanced ketonemia might be a feature of the state of adrenal insufficiency but is obscured by the ketone-lowering effect of the suboptimal circulation of this preparation. Careful search of the literature revealed one report (Thaddea and Kuhn, 1937) indicating that adrenal insufficiency in the cat may in fact be associated with elevated blood ketone levels during fasting and that these may be restored to normal by treatment with adrenal cortical extract.
Formation of well-defined MgO layers

Abstract Oxide layers of approximately 10 A in thickness have been formed in several laboratories by exposure of the Mg(0001) surface to oxygen exposures of 100 Langmuirs or less. Although there is good agreement of the oxygen uptake profiles in these studies, the structure and composition of these films are sensitive to the order of the metal surface and to the conditions of film growth. We review here the physical properties of MgO films as probed by spectroscopic techniques, and the application of these materials as models of the surface of bulk MgO. Studies of the chemical properties of oxide films may lead to identification of the active sites on bulk oxides, as well as providing information, complementing that from spectroscopic techniques, useful for characterizing the films themselves.
Hierarchical faceted metadata in site search interfaces

One of the most pressing usability issues in the design of large web sites is that of the organization of search results. A previous study on a moderate-sized web site indicated that users understood and preferred dynamically organized faceted metadata over standard search. We are now examining how to scale this approach to very large collections, since it is difficult to present hierarchical faceted metadata in a manner appealing and understandable to general users. We have iteratively designed and tested interfaces that address these design challenges; the most recent version is receiving enthusiastic responses in ongoing usability studies.
Evidence for coordinate regulation of the A system for amino acid transport and the mRNA for the alpha 1 subunit of the Na+,K(+)-ATPase gene in Chinese hamster ovary cells.

Abstract Previous work suggested that the structural gene for the A system transporter and the mRNA for the alpha subunit of the Na+,K(+)-ATPase in Chinese hamster ovary cells CHO-K1 [wild type (WT)] are coordinately controlled by regulatory gene R1. This conclusion was based on analysis of a mutant for the A system, alar4. This mutant had a constitutive level of A system transport activity equal to the level found in derepressed WT cells and a 4 times increase in abundance of the alpha 1 subunit of Na+,K(+)-ATPase mRNA over that found in repressed WT. The level of Na+ per cell in alar4 was not significantly greater than that found in the WT. To further characterize the likely coregulation of both genes, we have studied the A system activity and Na+,K(+)-ATPase mRNA alpha 1-subunit levels in cells grown under various conditions that result in repression or derepression of the A system in the WT. System A activity increased up to 2-3 times the basal transport rate (repressed state) and Na+,K(+)-ATPase mRNA alpha 1-subunit levels showed a 3-fold increase after amino acid starvation (derepressed state). These changes occurred along with a decrease in intracellular Na+ levels. N-Methyl-alpha-aminoisobutyric acid and beta-alanine, previously shown to be corepressors for the A system, prevented to a similar extent A system derepression and Na+,K(+)-ATPase mRNA alpha 1-subunit accumulation. On the other hand, phenylalanine and lysine, amino acids that are not corepressors of the A system, failed to significantly prevent derepression of both genes. Hybrids between the WT and alar4 have the phenotype of the WT when grown under repressed conditions. These results give further support to the proposition that both the A system transporter and mRNA for the alpha 1 subunit of the Na+,K(+)-ATPase are coordinately controlled by regulatory gene R1 and elevated Na+ concentrations are not involved. No Na+,K(+)-ATPase activity was detected in derepressed cells. Activity was restored by the addition of monensin. However, this activity was no greater than that obtained in repressed cells. Indications are that the reduced Na+ content in derepressed cells inhibits Na+,K(+)-ATPase activity and that conditions that favored derepression do not allow for de novo synthesis of the Na+,K(+)-ATPase.
Intraoperative percutaneous gastrostomyfor routine use in major urologic surgery

We describe a simple modification of the Russell technique that enables us to perform rapidly an effective gastrostomy at the time of major pelvic or retroperitoneal surgery without employing endoscopy or radiography
Pulse height defect due to electron interaction in the dead layers of Ge(li) γ-Ray detectors

Study shows the pulse-height degradation of gamma ray spectra in germanium/lithium detectors to be due to electron interaction in the dead layers that exist in all semiconductor detectors. A pulse shape discrimination technique identifies and eliminates these defective pulses.
Why another botanical magazine

To serve as a common meeting place for botanists, interested primarily in fundamental principles, and others who are concerned with economic applications of those principles and with the industrial utilization of plants and plant products.
Protein sequencing with radioisotopes

Recently, attention in a number of areas has been focused on proteins which are available only in trace quantities. For example refined immunological and pharmacological techniques have helped in the identification of specific cell surface antigens and hormone receptors, the potency of which allows them to exert a profound biological effect even when present at relatively low concentrations and when confined to one or a few tissues. Their low abundance, however, poses major problems in their isolation and characterization. Other proteins, although abundant in their mature form are known to be synthesized as precursors, whose metabolic lability prevents their isolation for chemical studies in anything but trace quantities. Sequence studies have been important in answering key biochemical and genetic questions concerning these proteins and we have attempted, in this article, to outline various approaches to the problem. The basic chemistry involved in protein sequence determination has remained essentially unchanged since the development by Edman of the sequential degradation reaction which degrades proteins or peptides by removing one residue at a time from the amino-terminus as shown in Fig. 1. The entire process has. been automated; instruments which perform lo-20 repetitive cycles of Edman degradation per day have been developed for sequencing proteins either under liquid phase conditions or with the proteins attached to solid supports. One factor which determines the amount of protein which must be used for sequence work is the sensitivity with which 5-anilinothiazolinones or their derivatives can be identified and quantified after sequencing. Back hydrolysis of thiazolinones to amino acids with hydriodic acid allows quantitative analysis of sequencer samples by amino acid analysis. The most sensitive amino acid analysers are capable ofquantitating approximately 10 lo moles of amino acid and this imposes a practical limit of lo-‘1O-s moles of protein for extended sequence determinations. Thiazolinones can alternatively be converted into phenylthiohydantoin (PTH) derivatives which can be identified by thin layer chromatography, gas liquid chromatoN 179
Three Faces of Empowerment: Expanding the Theory of Empowerment in Community Development

Empowerment as a process in leadership education is seen as fundamental to community development. Often, empowerment is considered only from the individual, psychological perspective in community development interventions. That is, practitioners may arguethat individuals basically empower themselves through personal knowledge, attitudes, and behavior (self-empowerment). The extensive literature on empowerment also makes clear that empowerment is an outcome of interpersonal (mutual empowerment) and collective social action (social empowerment). The extent to which community developers are incorporating these dimensions into their interventions via leadership education is explored. The results of the literature review indicate that these interventions fall short of fully utilizing what we know about empowerment and its role in community development.
Dark adaptation of the frog's rods

Abstract Using sodium aspartate Ringer's and isolated frog retinas we have recorded gross potentials from the frog's 502 (rhodopsin) rods. Substantial dark adaptation is seen at the receptor in the isolated retina in which little or no rod pigment regeneration occurs. Lights that bleach only a fraction of a per cent of rod pigment substantially decrease rod sensitivity, but sensitivity quickly returns to the prebleach level. With lights that bleach measurable amounts of pigment, the rods recover their sensitivity more slowly and show a permanent loss in sensitivity.
Comparison of visual and textual languages via task modeling

In order for comparative studies of programming languages to be meaningful, differences between the languages need to be carefully studied and well understood. Languages that appear to differ only in syntax (for example, visual vs. textual syntax) may in fact differ greatly in usability. Such differences can confound comparative studies unless they are controlled for. In this paper, we examine the usefulness of fine-grained task modeling for studying the usability of programming languages. We focus on program entry, and demonstrate how to create models of program entry tasks for both visual and textual languages. We also demonstrate how to derive performance time estimates from the models using keystroke-level analysis. A by-product of the model building is a collection of functional-level models that can serve as building blocks for modeling higher-level visual programming tasks. We then report on a comparative study of languages with the same semantics but different syntax (visual and textual). Model-based time predictions of program entry tasks were compared to observed times from an empirical study. The time estimates for the visual condition greatly overestimated the observed times. The primary source of the overestimates appeared to be the time estimate for pointing with the mouse. We then look at three different approaches to improving program entry models. We report on a separate study to calibrate the mouse-pointing time estimate, and demonstrate improved correlation between predicted and observed times with the new estimate. We also apply task modeling to program editing activities, in order to model error recovery behavior during program entry. Finally, we discuss language-specific customization of the keystroke-level operator for mental preparation. We conclude that task modeling is a useful technique for studying differences in the usability of programming languages at the keystroke level.
The use of honey as a carbohydrate in infant feeding

Summary Ten healthy male infants have been studied during the first 6 months of their lives for a total of 151 weeks. Formulas for all infants were restricted to either evaporated or dried milk and carbohydrate, with additional supplements of pure vitamin or mineral solutions. The response of the infants to honey as a source of carbohydrate has been contrasted with their response when receiving karo corn syrup. The general well-being of the infant, the number of stools per day, and weight gains have been used to determine the value of honey in regular feedings. Besides these criteria, blood sugar tolerance studies have been employed to contrast the response to honey with that resulting from administration of other common sources of carbohydrate. From these studies it is concluded that honey is easily digested, being absorbed more rapidly than most sugars during the first fifteen minutes after ingestion. It is well tolerated by the infant and does not cause diarrhea. It may facilitate weight gains, since there was a slight tendency for greater average gains per day to occur on lower calorie intakes when honey was included in the formulas. It would seem, therefore, that honey is a type of carbohydrate which is well suited to the infant's needs and probably should be recommended for wider use in infant dietaries.
A polarographic assay of cellulase activity.

Cellulase activity, or the susceptibility of cellulosic substrates to cellulolytic degradation, can be measured polarographically by coupling the liberation of glucose with oxygen consumption. The polarographic assay couples cellulase with an excess mixture of β-1,4-glucosidase (EC 3.2.1.21), glucose oxidase (EC 1.1.3.4), mutarotase (EC 5.1.3.3), and catalase (EC 1.11.1.6). Glucose oxidase couples β-d-glucose formation, the end product of cellulose hydrolysis, with the consumption of oxygen. Thus, the enzyme-coupled system provides a means of continuously monitoring cellulase activity, or the susceptibility of cellulosic substrates to enzymatic degradation, by measuring oxygen consumption in the reaction medium. The assay is capable of detecting glucose concentrations as low as 5 μg ml−1 and is particularly well suited for measuring cellulase activity in complex mixtures in which conventional assay methods cannot be used.
Seismic noise on Rarotonga: Surface versus downhole

Seismic noise data are presented from the new Global Seismographic Network station, RAR, on the Island of Rarotonga in the South Pacific. Data from the first new borehole site in the GSN are compared with a surface vault installation. Initial indications from the data show that borehole siting on a small island significantly reduces long-period (>20 s) horizontal seismic noise levels during the daytime, but little or no improvement is evident at periods shorter than 20 s or on the vertical component. The goal of the Incorporated Research Institutions for Seismology (IRIS) GSN program is broad, uniform coverage of the Earth with a 128-station network. To achieve this goal and provide coverage in oceanic areas, many stations will be sited on islands. A major siting consideration for these new stations is whether to build a surface vault or drill a borehole. Neither option is inexpensive. The costs for drilling a cased hole and a borehole sensor are large, but the benefit of a borehole site is that seismic noise is reduced during certain periods when a surface installation may be subject to wind, weather, and thermal effects. This benefit translates into recording greater numbers of smaller earthquakes and higher signal-to-noise ratio.
A Comparison of Patients with Endoscopic Esophageal Perforations and Patients with Boerhaave's Syndrome

A review was conducted to ascertain whether patients who suffered spontaneous postemetic esophageal rupture (Boerhaave's syndrome) experienced higher morbidity and mortality than patients who had endoscopic iatrogenic esophageal perforations. Review of the records of three medical centers from 1960 to 1985 identified 11 patients with Boerhaave's syndrome (group B) and 19 with iatrogenic perforations (group E). In group B, four patients were diagnosed greater than 24 h after perforation. Nine were treated surgically; of these one died. Two group B patients who were treated conservatively survived. In group E, only four patients were diagnosed greater than 24 h after perforation. Of 19 patients, 15 were treated surgically and four, medically. In group E, three patients died (one surgically and two conservatively treated). This study suggests that there is little difference in mortality between the two groups of patients as long as the diagnosis is made early and therapy is instituted promptly.
Role of Trehalose in Ascospores of Neurospora Tetrasperma

The anthrone-positive material extractable in 80 percent alcohol, whose disappearance is correlated with the breaking of dormancy, has been found to be a non-reducing sugar which yields only glucose upon hydrolysis. On the basis of its crystal structure, infrared spectrum, melting point, specific rotation, and chromatographic properties, this material has been identified as trehalose.
Minor and trace sterols in marine invertebrates V. isolation, structure elucidation and synthesis of 3β-hydroxy-26,27-bisnorcholest-5-en-24-one from the sponge Psammaplysilla Purpurea

Abstract The free sterol mixture of the sponge Psammaplysilla purpurea was shown to contain aplysterol as the major constituent. In addition to other sterols such as 5,7-cholestadien-3β-ol, cholesterol, 5α-cholestan-3β-ol, 24e-methylcholesta-5,22-dien-3β-ol, 24e-methylcholesterol, 24e-ethylcholesta-5,22-dien-3β-ol and 24,28-dehydroaplysterol, a new minor sterol was isolated and shown by spectral analysis as well as partial synthesis to be 3β-hydroxy-26,27-bisnorcholest-5-en-24-one. The sterol mixture contains no other short side chain or 24-keto sterols except for small amounts of 3β-hydroxypregn-5-en-20-one and 3β-hydroxy-5α-pregnan-20-one.
Isolation and Nucleotide Sequence of Canine Glucose-6-phosphatase mRNA: Identification of Mutation in Puppies with Glycogen Storage Disease Type Ia☆☆☆

Abstract Two Maltese puppies with massive hepatomegaly and failure to thrive had isolated deficient glucose-6-phosphatase (G-6-Pase) activity in liver and kidney and pathological findings compatible with GSD-Ia. To identify the mutation, we cloned G-6-Pase canine cDNA by RT–PCR with primers from the murine G-6-Pase gene sequence. The canine G-6-Pase cDNA is 2346 bp, with a 5′ untranslated region of 87 bp, a coding region of 1071 bp, and a 3′ untranslated region of 1185 bp. The difference between the canine and human sequences is in the 3′ untranslated region. A greater than 90% amino acid sequence homology was seen with canine, human, murine, and rat G-6-Pase. G-6-Pase cDNA from affected and control puppies revealed complete homology except at nt position 450, which showed a guanine to cytosine (G to C) transversion resulting in substitution of a methionine by isoleucine at codon 121 (M121I) in all five clones studied. The loss of an Nco I restriction site on genomic DNA amplified with primers flanking the mutation allowed us to prove that affected puppies were homozygous for the mutation and parents were heterozygous carriers. The mutant G-6-Pase cDNA had 15 times less enzyme activity than wild-type cDNA following transient transfection. Northern blot analysis of puppies with GSD-Ia revealed increased G-6-Pase mRNA, compared to normal controls. Increased G-6-Pase mRNA was also seen in normal fasted puppies compared to littermates in the fed state, suggesting that the increased G-6-Pase mRNA is a physiologic response to fasting. This is the first report of a molecularly confirmed naturally occurring animal model of GSD-Ia. The establishment of a breeding colony of this dog strain will facilitate studies on the role of G-6-Pase gene in glucose homeostasis, in pathophysiology of disease, and development of novel therapeutic approaches such as gene therapy.
Doping vs alloying in amorphous hydrogenated boron carbide

Abstract We have grown amorphous hydrogenated boron carbide thin films with boron concentrations ranging from 0 to 18 atomic percent by plasma decompostion of a feedstock of diborane and methane. The chemical composition, optical bandgap, and electrical conductivity activation energy data provide convincing evidence that this material is an alloy at high boron concentrations. On the other hand, the electrical conductivity prefactors, which are proportional to the acceptor densities, demonstrate that the boron also acts like a dopant, with increasing boron concentrations leading to increasing acceptor densities. Finally, the samples with the highest boron concentrations also had the highest hydrogen concentrations — 61 atomic percent — strongly suggesting that this material is a tenuous boron-carbon matrix with plenty of methyl, methylene and borene groups hung from the matrix.
Principles of calculating alignment signals in complex resonant optical interferometers

In the long-baseline laser interferometers that are now under construction to measure gravitational waves, the alignment of the optical components with respect to the incoming laser beam is crucial for maintaining maximum phase sensitivity. We present a basic formalism to calculate the effects of misalignment and beam distortions analytically in an arbitrarily complex optical system, including coupled cavities and Michelson interferometer configurations coupled with cavities. The electromagnetic field is decomposed into a superposition of higher-order Gaussian modes, while misaligned and distorting optical components along with free-space propagators are represented by matrix operators that act on the state vectors in this basis. We show how to deduce useful alignment signals generally, in order to design angular control systems.
Homemakers' household‐work time in single‐parent and two‐parent families

The purpose of this study was to determine if a significant difference existed between single-parent family homemakers and two-parent family homemakers regarding the amount of time spent in selected household tasks. The examination of the impacts of selected socio-demographic variables on the amount of time spent in total household work and the component tasks by the homemakers was also a part of this study.
Influences of Social Context on Parent Guidance and Low-Income Preschoolers' Independent and Guided Math Performance.

Mathematical knowledge at school entry predicts school achievement, and children from low-income families are at risk for low math achievement. The study purpose was to observe low-income parents' numeracy guidance in two contexts, a board game and a number concept assessment, and to compare preschoolers' independent and guided math performances. Eighteen four-year-olds enrolled in Head Start participated with one parent. Although parents employed guidance for a wider range of math activities during the number assessment activity as compared with the board game, the total guidance provided in each context did not differ. In both contexts, children performed at a higher level when guided by a parent as compared with independent math performance. Parental reports of home numeracy practices were positively correlated with children's math abilities but not with observed parent guidance. The findings provide further support for the importance of adult guidance in order to enhance children's opportunities to re...
Economic Evaluation of Treatment of Gastro-Oesophageal Reflux Disease in the United States

Gastro-oesophageal reflux disease (GORD), including endoscopically confirmed reflux oesophagitis of grade II and above [termed severe erosive oesophagitis (SEO)], is a common but difficult to diagnose illness. Symptoms are often not closely correlated with pathological findings. A decision analysis found empirical therapy based on initial treatment with omeprazole to be a dominant strategy for SEO compared with ranitidine or phase I therapy. Phase I therapy, the most common treatment, includes antacids, cessation of smoking, reduction of alcohol consumption, weight loss, dietary changes, and elevating the head of the bed. A subsequent randomised controlled trial found that omeprazole was a more cost-effective strategy than ranitidine plus metoclopramide; clinical outcome was better in the omeprazole-treated group than in the rani-tidine/metoclopramide group, while cost was similar in both groups. However, the changing of treatment strategies (e.g. modifying dosages and regimens), or new surgical interventions, require periodic re-evaluation of the cost-effectiveness of all alternative therapies for GORD.
Sequence-dependent structural variations of hammerhead RNA enzymes

The discovery of in vivo catalytic activity for the hammerhead RNA self-cleaving domain has led to the development of a new class of sequence-specific RNA endonucleases. Two such ribozymes have been synthesized using in vitro transcription with T7 polymerase and their structures have been studied by optical spectroscopy, nuclear magnetic resonance and nondenaturing gel electrophoresis. These data show the presence of a stable hairpin consisting of a double helical stem and a tetranucleotide loop in both RNA enzymes. Additional structure, with different stabilities, is also observed in both RNA enzymes. The half-lives for cleavage of the complementary RNA substrates by these two RNA enzymes have been previously shown to differ by a factor of 50. The data presented here suggest that this rate difference may be a result of the formation of catalytically inactive conformations in the RNA enzyme which interfere with formation of the enzyme-substrate complex.
Multidisciplinary design optimisation under uncertainty: an information model approach

The design of a multi–purpose vehicle capable of performing diverse missions in diverse environmental conditions requires a multi–disciplinary approach. Uncertain missions implied by a multi–purpose design goal and uncertain environmental conditions resulting from multiple operating theatres involve tradeoffs in vehicle performance. An information model approach to handling tradeoffs is presented. The design process is conceptualized as proceeding in stages. At each stage, the design problem is decomposed from the top down into design levels and interacting components having uncertain elements on each level. The components may require different knowledge bases and models with different mathematical structures, time and size scales, calling for higher–level coordination. Component performances are modelled as random functions of uncertainties considered as deterministic variables. Information models are developed making use of second–order statistics of the random performance functions and an algebra of their reduced–order representations. Decision–making proceeds from the bottom up. Higher–level design decisions, the result of tradeoffs between alternative component designs, are based on the information models of the component performance functions. Preferred overall designs are determined within a finite set of feasible designs by means of multi–criteria optimisation methods without using mathematical programming. The methodology is illustrated by a simplified two–component vehicle design problem.
Nanoscale Characterization of Elemental Partitioning between Gamma and Gamma Prime Phases in René 88 DT Nickel-Base Superalloy

The chemical partitioning of alloying elements between the disordered γ and ordered γ′ phases in the nickel-base superalloy Rene 88 DT, has been characterized in detail using three-dimensional atom probe tomography (3DAP) coupled with energy-filtered transmission electron microscopy (EFTEM) studies. After a homogenization treatment followed by a water quench, it is observed that the morphology of the γ′ precipitates remains near spherical even after long aging times. Compositional variation, observed between small (<5 nm) and larger γ′ precipitates, reduces with increasing aging time, while the compositional gradient across the γ/γ′ interface decreases. The process of growth of γ′ precipitates seems to occur through coalescence of adjacent γ′ precipitates, facilitated through the formation of “necks” between adjacent precipitates. These necks are observed to have intermediate elemental concentration values between the matrix and the γ′ precipitate compositions.
Monolithic GaAs surface acoustic wave chemical microsensor array

A four-channel surface acoustic wave (SAW) chemical sensor array with associated RF electronics is monolithically integrated onto one GaAs IC. The sensor operates at 690 MHz from an on-chip SAW based oscillator and provides simple DC voltage outputs by using integrated phase detectors. This sensor array represents a significant advance in microsensor technology offering miniaturization, increased chemical selectivity, simplified system assembly, improved sensitivity, and inherent temperature compensation.
An accurate interconnect thermal model using equivalent transmission line circuit

This paper presents an accurate interconnect thermal model for analyzing the temperature distribution of an on-chip interconnect wire. The model addresses the ambient temperatures and the heat transfer rates of the packaging materials. Particularly, the model considers the effect of the interconnect temperature gradients. The paper employs an equivalent transmission line circuit to obtain the temperature distribution solution from the model. Then an O (n) algorithm is introduced to compute the interconnect temperatures. Experimental results demonstrate the accuracy of the thermal model, by comparisons with the computational fluid dynamics tool FLUENT.
Effects of Mn and Fe Levels on Bacillus subtilis Spore Resistance and Effects of Mn2+, Other Divalent Cations, Orthophosphate, and Dipicolinic Acid on Protein Resistance to Ionizing Radiation

Spores of Bacillus subtilis strains with (wild type) or without () most DNA-binding /-type small, acid-soluble proteins (SASP) were prepared in medium with additional MnCl2 concentrations of 0.3 Mt o 1 mM. These haploid spores had Mn levels that varied up to 180-fold and Mn/Fe ratios that varied up to 300-fold. However, the resistance of these spores to desiccation, wet heat, dry heat, and in particular ionizing radiation was unaffected by their level of Mn or their Mn/Fe ratio; this was also the case for wild-type spore resistance to hydrogen peroxide (H2O2). However, spores were more sensitive to H2O2 when they had high Mn levels and a high Mn/Fe ratio. These results suggest that Mn levels alone are not essential for wild-type bacterial spores’ extreme resistance properties, in particular ionizing radiation, although high Mn levels sensitize spores to H2O2, probably by repressing expression of the auxiliary DNA-protective protein MrgA. Notably, Mn 2 complexed with the abundant spore molecule dipicolinic acid (DPA) with or without inorganic phosphate was very effective at protecting a restriction enzyme against ionizing radiation in vitro, and Ca 2 complexed with DPA and phosphate was also very effective in this regard. These latter data suggest that protein protection in spores against treatments such as ionizing radiation that generate reactive oxygen species may be due in part to the spores’ high levels of DPA conjugated to divalent metal ions, predominantly Ca 2 , much like high levels of Mn 2 complexed with small molecules protect the bacterium Deinococcus radiodurans against ionizing radiation.
Normal Faulting and Lateral Shear in Northeastern California

Extension of the Earth's crust is necessarily related to normal faulting. Causes of the necessary extension are obscure, however, and have been the subject of a variety of explanations. In northeastern California there is strong indication that the extension is the product of deep-seated right-lateral shear deformation related to the Walker Lane. Tectonic evidence, sharply etched in volcanic materials, suggests that (1) in a broad zone of lateral shear, normal faulting is due to the dynamic tension of the shear deformation and will differ in nature from that produced by compressive stress fields, and (2) an older set of Walker Lane lineaments exists which has been rotated away from present lateral stress and is now under constructional controls. Northeastern California provides evidence for the hypothesis suggested by Wise in 1963.
Benign and Malignant Breast Tumours: Epidemiological Similarities

Reproductive risk factors were estimated for 783 cases of cystic disease of the breast, 155 fibroadenoma, 94 miscellaneous breast conditions, and 284 breast cancers. Controls were matched for age, race, ever-married status, time of hospitalization and pay status. The most consistent attributes are a tendency to be still premenopausal, to have had her first pregnancy beyond the age of twenty-five years (or to have had none), and to have had fewer total pregnancies than the control. All are associated with a longer menstrual life prior to onset of the disease than the controls. Findings for cystic disease are compared with other studies. Patients with benign breast disease share some of the demonstrated risk factors for breast cancer.
Development of a skin for intuitive interaction with an assistive robot

Assistive robots for persons with physical limitations need to interact with humans in a manner that is safe to the user and the environment. Early work in this field centered on task specific robots. Recent work has focused on the use of the MANUS ARM and the development of different interfaces. The most intuitive interaction with an object is through touch. By creating a skin for the robot arm which will directly control its movement compliance, we have developed a novel and intuitive method of interaction. This paper describes the development of a skin which acts as a switch. When activated through touch, the skin will put the arm into compliant mode allowing it to be moved to the desired location safely, and when released will put the robot into non-compliant mode thereby keeping it in place. We investigated four conductive materials and four insulators, selecting the best combination based on our design goals of the need for a continuous activation surface, the least amount of force required for skin activation, and the most consistent voltage change between the conductive surfaces measured during activation.
I-III-VI2 (Copper Chalcopyrite-based) Thin Films for Photoelectrochemical Water-Splitting Tandem-Hybrid Photocathode

This presentation will investigate various parameters regarding the use of I-III-VI2 Copper Chalcopyrite-based materials for use in tandem-hybrid photocathodes capable of splitting water into hydrogen and oxygen gases in an acidic electrolyte. Constituent parts (fabricated at HNEI) of a proposed monolithically integrated hybrid photovoltaic/photoelectrochemical (PV/PEC) device were characterized separately and combined theoretically using electronic and optical models to simulate tandem operation to first indicate feasibility of matching existing materials. Robust CGSe2 photocathodes were focused on for the PEC cells and CIGSe2 and CISe2 devices were evaluated for the PV cells. Simulation suggested the hybrid PV/PEC system could pass enough light to produce up to 15.87mA/cm2, validating the feasibility and warranting the fabrication of stacked PV/PEC devices.
Do Partners With Children Know About Firearms in Their Home? Evidence of a Gender Gap and Implications for Practitioners

OBJECTIVE: The gender gap describing the apparent differences in male and female reports of firearm-ownership and -storage habits has never been evaluated among individuals who live in the same household. Thus, the objective of this study was to examine the level of agreement on household firearms and storage practices among cohabiting partners. METHODS: Data for this investigation came from follow-up telephone interviews of participants who underwent a randomized, controlled trial to test the effect of home-safety counseling, including firearm safety, on behavior change. Baseline interviews were conducted at a level 1 pediatric emergency department in North Carolina with adults who took a child or adolescent who was under his or her care to a pediatric emergency department. Follow-up interviews were conducted via telephone at 18 months after intervention with participants who reported household firearms at baseline. Participants then were asked whether their partners could be contacted for a separate telephone interview. The measured outcomes were number and type of household firearms and firearm-storage practices. The strength of agreement between partners' reported firearm-ownership and -storage practices was measured with the kappa statistic. RESULTS: Seventy-six partner-respondent pairs completed the study (62% response rate). Most initial respondents were white (89%), female (76%), and college graduates (52%); the median age was 37. There were no same-gender partners, and 91% reported that they were spouses. There was not perfect agreement among male and female partners with regard to the presence of household firearms. More men (80%) reported the presence of household firearms than did women (72%; kappa = .64). The discordance between partner pairs regarding the number of household firearms and type was poor to fair (kappa = .35 and .34, respectively). Although similar proportions of men and women reported storing any household firearms loaded (10%) and storing all household firearms locked up (63% men and 62% women), the kappa values demonstrated only moderate agreement (kappa = .56-.60). Most men (88%) and women (83%) reported that firearm storage was the husband's responsibility; 82% of men compared with 17% of women reported that they personally owned all of the firearms. CONCLUSIONS: A gender gap does exist in the reporting of firearm ownership with regard to the number and type of firearms owned. There are also differences in reported firearm-storage practices, which are likely related to the finding that men were reported to be the primary owner of firearms in most households as well as the person more commonly responsible for firearm storage. Firearm-safety counseling should include male partners in the history-taking process to improve knowledge about the presence and storage patterns of household firearms.