cssi/SciSciGPT-SciSciNet huggingface dataset:
On the initial growth of atomic layer deposited TiO2 films on silicon and copper surfaces

Abstract Atomic layer deposition (ALD) of TiO2 using tetrakis(diethylamino)titanium precursor and H2O was studied on silicon and copper surfaces in order to examine differences in nucleation. Both surfaces were patterned on the same substrate to assure identical deposition conditions. Spectral ellipsometry, X-ray photoelectron spectroscopy and surface profilometry were used to probe nucleation phenomena, growth rates, and surface morphology on both surfaces. The TiO2 deposition on copper was found to exhibit a significant induction period of about 20–25 ALD cycles with no observable TiO2 during the first 10–15 cycles on the copper side; in contrast, no such inhibited growth was observed in the TiO2 deposition on silicon. This result opens up potential for selective ALD of TiO2 films on silicon-based substrates patterned with a metal without the use of a mask, a self-assembled monolayer or soft lithography which is impractical for some nanoscale semiconductor fabrication processes. After film nucleation, the TiO2 growth rate on both surfaces was found to be 0.10 nm/cycle.
Reasoning about non-immediate triggers in biological networks

Modeling molecular interactions in signalling networks is important from various perspectives such as predicting side effects of drugs, explaining unusual cellular behavior and drug and therapy design. Various formal languages have been proposed for representing and reasoning about molecular interactions. The interactions are modeled as triggered events in most of the approaches. The triggering of events is assumed to be immediate: once an interaction is triggered, it should occur immediately. Although working well for engineering systems, this assumption poses a serious problem in modeling biological systems. Our knowledge about biological systems is inherently incomplete, thus molecular interactions are constantly elaborated and refined at different granularity of abstraction. The model of immediate triggers can not consistently deal with this refinement. In this paper we propose an action language to address this problem. We show that the language allows for refinements of biological knowledge, although at a higher cost in terms of complexity.
A high resolution transmission electron microscope study of early stage precipitation on dislocation lines in Al-Zn-Mg

The weak beam transmission electron microscopy technique was employed to study the early stages of precipitation on dislocation lines in Al-3.87 wt pct Zn-1.79 wt pct Mg. The heterogeneous precipitation sequence was found to follow the homogeneous sequence in this alloy. The interaction between the initial coherent precipitate particles and the strain fields of the catalyzing dislocations produced “gaps” of background intensity at precipitate locations along the otherwise continuous weak beam images of the dislocation lines. A simple model was developed to relate a distribution of measured weak beam gap lengths to a particle size distribution at a given aging treatment. In this manner the growth kinetics of the initial precipitate phase was observed; it was found that the precipitation followed the Cottrell-Bilbyt 2/3law, suggesting that matrix dislocations may assist the growth of heterogeneous precipitates in a manner analogous to grain boundary “collector plates.” Weak beam microscopy was found to be superior to standard bright field microscopy for the current study. Particles too small to be visible in bright field were revealed in weak beam. Weak beam observations also indicated that the coherent precipitate particles were positioned asymmetrically about the dislocation cores.
PROBABILITY-POSSIBILITY TRANSFORMATIONS: A COMPARISON

After a brief discussion of the relationship between probability theory and possibility theory, the paper overviews the various proposed probability-possibility transformations. Principles by which these transformations are justified are critically examined, which results in some conclusions as well as the identification of issues that require further research.
Selectivity of chromatin-remodelling cofactors for ligand-activated transcription.

An array of regulatory protein and multi-subunit cofactors has been identified1 that directs eukaryotic gene transcription. However, establishing the specific functions of various related cofactors has been difficult owing to the limitations inherent in assaying transcription in animals and cells indirectly. Here we describe, using an integrated chromatin-dependent reconstituted transcription reaction, the purification and identification of a multi-subunit cofactor (PBAF)2 that is necessary for ligand-dependent transactivation by nuclear hormone receptors. A highly related cofactor, human SWI/SNF3, and the ISWI-containing chromatin-remodelling complex ACF4 both fail to potentiate transcription. We also show that transcriptional activation mediated by nuclear hormone receptors requires TATA-binding protein (TBP)-associated factors (TAFs) as well as the multi-subunit cofactors ARC5/CRSP6. These studies demonstrate functional selectivity amongst highly related complexes involved in gene regulation and help define a more complete set of factors and cofactors required to activate transcription.
Historical landmarks in progress relating to iron chlorosis in plants

Abstract Iron deficiency has long been considered to be the most difficult of nutrient deficiencies in plants to understand and to correct. After the landmark discovery in 1843 that lime‐induced chlorosis was a form of iron deficiency, progress was slow for the next 100 years. Many, but not all, of the scientific giants who made significant progress on understanding iron chlorosis and iron physiology in plants in the 1940's and 1950's have passed away. Thome was certain that ferrous iron was the key to understanding the disorder. Kliman had suggested uptake of Pe in the ferrous form. Iljin found that iron chlorotic leaves had high levels of free amino acids, high levels of citrate and total organic acids, were high in P and K and low in Ca concentrations. These are the criteria that generally identify iron chlorosis. Shive and his students found an Fe‐Mn interaction through which Fe deficiency can be induced. Warm found that lime‐induced chlorosis in grapes could be largely prevented if resistant rootstoc...
The Schützenberger Group of an H-class in the Semigroup of Binary Relations

K. A. Zaretskii has associated a lattice V(α) with each binary relation α, and he has shown that Hα is isomorphic with the group of all automorphisms of V(α) if Hα is a group. This result is extended in this paper by showing that for any binary relation α, the Schutzenberger group Γ (Hα) is isomorphic with the group of all automorphisms of V(α).
Driver contrast sensitivity and reaction times as measured through a salt-covered windshield

Abstract Background The objective of this study was to use contrast sensitivity measurements to determine the effect of windshield salt film on driver vision. This effect simulates road salt spray that dries in place on a vehicle windshield during winter driving conditions. Methods Ten emmetropic subjects were tested to assess contrast sensitivity functions through windshields that were clear compared with the same stimuli as viewed through windshields coated with salt film. Achromatic stimuli were generated by a VisionWorks system and were presented at 4 spatial frequencies (0.5, 3, 10, and 20 cycles per degree). Results A significant reduction in contrast sensitivity through the salt film was found at all spatial frequencies. In addition, reaction time to detect the stimuli was also found to be increased significantly at 2 of the 4 spatial frequencies through the saline-covered windshield. Conclusion The results of this study indicate that windshield salt film reduces the ability to detect high and low contrast objects in a simulated driving environment as well as increases the subjects’ reaction times.
On tightness of partial sums from strictly stationary, absolutely regular sequences of B-valued random variables

Abstract For strictly stationary, absolutely regular sequences of random variables taking their values in a separable real Banach space, the property of tightness of the partial sums follows from tightness of the bounded linear functionals of those sums. The same is true for “shift-tightness.”
On ‘Maxwell's laws’ of individual behaviour

Abstract Any theory of choice under uncertainty in which choice depends on locally linear evaluations of univariate probability density functions has precisely two testable implications. These are 1. (a) d ũ = Ω 2. (b) ★d★ ũ = φ. Here φ, ũ , and Ω are differential forms, φ a zero-form, ũ a one-form, and Ω a two-form. d is the exterior derivative operator on forms, and ★ is the Hodge star operator. In this letter we explain in a non-technical way the meaning and import of equations (a) and (b). A fuller treatment will be found in Russell (1989).
Regional coronary flow with increased right ventricular output in anesthetized dogs.

Abstract In this study of acute right ventricular volume overloading in anesthetized dogs, right ventricular coronary blood flow increased, probably in response to the effect of increased right ventricular pressure on myocardial oxygen needs. Left-to-right shunts with small elevations in right ventricular pressure had compensatory coronary vasodilatation which increased coronary flow. However, shunts with right ventricular hypertension had no further fall in coronary resistance and failed to have an additional increase in coronary flow. This suggests that with acute right ventricular volume overloading the presence of right ventricular hypertension increases myocardial oxygen needs but limits the ability of the coronary vessels to increase flow. Should myocardial oxygen needs increase and the coronary vessels be unable to increase myocardial perfusion, relative coronary insufficiency may occur.
Serum corticosterone concentrations in immature captive whitetip reef sharks, Triaenodon obesus

Serum concentrations of the steroid hormone corticosterone were monitored over a four-year period in two male and two female immature captive whitetip reef sharks, Triaenodon obesus. Corticosterone concentrations in the serum ranged from 69–999 pg/ml (319.8 ± 31.9; n = 36) for males and 3–246 pg/ml (116.0 ± 15.1; n = 32) for females. Males had significantly higher values than females (P < 0.001). No significant difference was detected between females; however, a significant difference was observed between the two males. No seasonality was observed in corticosterone levels. Corticosterone levels in elasmobranchs are only 10% the levels of the principal glucocorticoid, 1α-hydroxycorticosterone, but the assay is inexpensive and readily available, and, once individual ranges are established, the corticosterone concentrations have utility. Our data suggest that, after these baseline levels are established for individual sharks, long-term monitoring of serum corticosterone in captive populations may be utilized to monitor health or, conversely, stress. © 1993 Wiley-Liss, Inc.
Performance Characteristics of the Aerosol Collectors of the Autonomous Pathogen Detection System (APDS)

This research analyzes the physical performance characteristics of the aerosol collectors of the autonomous pathogen detection system (APDS) that was recently developed by the Lawrence Livermore National Laboratory. The APDS is capable of continuous and fully autonomous monitoring for multiple airborne threat organisms and can be used as part of a monitoring network for urban areas and major public gatherings. The system has already been successfully tested with airborne Bacillus anthracis and Yersinia pestis biowarfare agents. The APDS aerosol collection system consists of a PM-style cap to remove large particles and a low-pressure drop virtual impactor preconcentrator positioned in front of a wetted-wall cyclone. The aerosol collectors operate at flow rates as high as 3750 l/min and collect airborne particles into 4 ml of liquid for subsequent detection. In our tests we determined the overall collection efficiency of the system by measuring the difference between inlet and outlet particle concentrations...
Making Learning Visible through Documentation: Creating a Culture of Inquiry among Pre-Service Teachers

This article explores the use of documentation—to observe, record, and interpret the learning of children and their pre-service teachers to make that learning visible in order to point to it and engage in a collaborative dialogue. Inspired by the work of the Reggio Emilia infant-toddler and pre-schools in Italy, this study extends the idea of documenting young children’s individual and group learning to adult learning in a graduate seminar with nine pre-service teachers. Shifts made to teaching a seminar included professor and pre-service teachers co-constructing the meaning of a learning group, following a protocol to look at children’s work, sharing public reflections, interpreting the learning that took place both between and in each seminar. The explicit effort to document adult learning led to creating a collective body of knowledge that extended to documenting children’s learning in elementary inclusive classrooms.
EFFECT OF AL PARTICLE SIZE ON THE THERMAL DEGRADATION OF AL/TEFLON MIXTURES

Abstract Reactive mixtures of aluminum (Al) and polytetrafluoroethylene (PTFE or Teflon) have applications in propellants, explosives, and pyrotechnics. This study examines the thermal degradation behavior of Teflon and nanometer scale Al particles compared with micron-scale Al particles. Differential scanning calorimetry and thermo-gravimetric analyses were performed in an argon environment on both nanometer and micron scale particulate mixtures revealing lower ignition temperatures and larger exothermic activity for the nanometer Al/Teflon mixture. This increased ignition sensitivity and exothermicity is caused by a pre-ignition reaction unique to the nano-Al mixture. Experiments suggest that the pre-ignition reaction mechanism is controlled by the fluorination of the Al particle passivation shell. Micron-scale Al particles have a lower specific surface area and therefore the influence of the passivation shell promoting a pre-ignition reaction is reduced. Chemical kinetics are discussed along with parti...
Statistics for measuring the efficiency of electronic information retrieval

As electronic information searching with different software strategies and interactive systems becomes the only way to access desired holdings, the need to measure the efficiency of individual search strategies becomes critical to the research process that drives our choice of systems and instruction. Formal experimental research depends on the choice and use of an appropriate statistical technique. The relationship, between two dichotomously categorized variables distributed on an underlying continuous distribution is a tetrachoric correlation. This statistic was described at least as long ago as the turn of the century (Pearson, 1901, Philosophical Transactions of the Royal Society of London, 195A, pp. 1–47). It is a special case of a Pearson r and may be considered as an estimate of the product moment correlation (Guilford & Fruchter, 1978, Fundamental Statistics in Psychology and Education, 6th ed.). There are a number of ways that a researcher could use this statistic in a research design to measure information searching efficiency. The use of the tetrachoric correlation for experimental research and hypothesis testing of the efficiency of computerized information searching is described and illustrated. © 1996 John Wiley & Sons, Inc.
Continuous ice core melter system with discrete sampling for major ion, trace element and stable isotope analyses.

We present a novel ice/firn core melter system that uses fraction collectors to collect discrete, high-resolution ( 32 trace elements by inductively coupled plasma sector field mass spectrometry (ICP-SMS), and stable oxygen and hydrogen isotopes by isotope ratio mass spectrometry (IRMS). The new continuous melting with discrete sampling (CMDS) system preserves an archive of each sample, reduces the problem of incomplete particle dissolution in ICP-SMS samples, and provides more precise trace element data than previous ice melter models by using longer ICP-SMS scan times and washing the instrument between samples. CMDS detection limits are similar to or lower than those published for ice melter systems coupled directly to analytical instruments and are suitable for analyses of polar and mid−low-latitude ice cores. Analysis of total calcium and sulfur by ICP-SMS and calcium ion, s...
Immunoglobulins as glycoproteins—I determination of neutral sugars and hexosamines in bovine gamma globulin by hexosamines in bovine gamma globulin by gas-liquid chromatography☆

Abstract Techniques for analysis of immunoglobulin neutral sugars and hexosamines are described, including details of hydrolysis, acetylation, formation of trimethylsilyl derivatives, and their detection by gas-liquid chromatography. Data obtained with bovine gamma globulin are presented.
Is there Kveim responsiveness in Crohn's disease?

Summary No microscopically positive Kveim reactions were observed among 23 patients with Crohn's disease. The Kveim-test suspensions employed in this study, spleen J and K 12, were potent and specific as judged by the high proportion of positive Kveim reactions (83–87%) concurrently evoked by the suspensions in 30 patients with sarcoidosis and by the negative Kveim reactions among 15 patients with non-granulomatous disorders. These uniformly negative results are not in accord with recent reports of frequent positive Kveim reactions in patients with Crohn's disease. Closer scrutiny of the specificity of various lots of Kveim-test suspensions now in use may be required to explain the discordant results of Kveim testing in patients with Crohn's disease.
New linear codes from constacyclic codes

One of the main challenges of coding theory is to construct linear codes with the best possible parameters. Various algebraic and combinatorial methods along with computer searches are used to construct codes with better parameters. Given the computational complexity of determining the minimum distance of a code, exhaustive searches are not feasible for all but small parameter sets. Therefore, codes with certain algebraic structures are preferred for both theoretical and practical reasons. In this work we focus on the class of constacyclic codes to first generate all constacyclic codes exhaustively over small finite fields of order up to 9 to create a database of best constacyclic codes. We will then use this database as a building block for a search algorithm for new quasi-twisted codes. Our search on constacyclic codes has revealed 16 new codes, i.e. codes with better parameters than currently best-known linear codes. Given that constacyclic codes are well known, this is a surprising result. Moreover, using the standard constructions of puncturing, shortening or extending a given code, we also derived 55 additional new codes from these constacyclic codes. Hence, we achieved improvements on 71 entries in the database of best-known codes. We use a search strategy that is comprehensive, i.e. it computes every constacyclic code for a given length and shift constant, and it avoids redundantly examining constacyclic codes that are equivalent to either cyclic codes or other constacyclic codes.
Myeloperoxidase binds to low-density lipoprotein: potential implications for atherosclerosis

Myeloperoxidase (MPO), an abundant heme enzyme released by activated phagocytes, catalyzes the formation of a number of reactive species that can modify low-density lipoprotein (LDL) to a form that converts macrophages into lipid-laden or ‘foam’ cells, the hallmark of atherosclerotic lesions. Since MPO has been shown to bind to a number of different cell types, we investigated binding of MPO to LDL. Using the precipitation reagents phosphotungstate or isopropanol, MPO co-precipitated with LDL, retaining its catalytic activity. The association of MPO with LDL was confirmed using native gel electrophoresis. MPO was also found to co-precipitate with apolipoprotein B-100-containing lipoproteins in whole plasma. No precipitation of MPO was observed in lipoprotein-deficient plasma, and there was a dose-dependent increase in precipitation following addition of LDL to lipoprotein-deficient plasma. Binding of MPO to LDL could potentially enhance site-directed oxidation of the lipoprotein and limit scavenging of reactive oxygen species by antioxidants.
A comparison of differential and integral equations of radiative transfer

Abstract The equations of radiative transfer and of statistical equilibrium of a two-level atom are solved by means of differential and integral equations for a one-dimensional medium. The numerical solutions are compared to the analytic solution. It is found that the integral equation for piecewise quadratic source functions gives more accurate results than does the differential equation.
Initial Validation of a Scale Measuring Self-Efficacy of Breast Self-Examination among Low-Income Mexican American Women

This paper presents the initial validation of a bilingual (English/Spanish) scale designed to assess intensity of perceived self-efficacy for breast self-examination (BSE) among low-income Mexican ...
Tailored Transport through Vertically Aligned Carbon Nanofibre Membranes; Controlled Synthesis, Modelling, and Passive Diffusion Experiments

The ability to control the permeability of a synthetic membrane structure formed by a spatially stochastic forest of vertically aligned carbon nanofibres is demonstrated. Control of membrane pore size and morphology was achieved by varying the thickness of a uniform, conformal coating of SiO2 on the nanofibre surfaces. Characterization of passive diffusion using fluorescence microscopy and labelled latex beads confirms the ability to alter membrane permeability. Further, statistically reproducible transport regimes are predicted for the spatially stochastic membrane as a function of the nanofibre diameter by a Monte Carlo simulation technique. Realizing predictable nanoscale behaviour in a microscopically random, statistical structure is essential for applications requiring controlled, species specific transport.
Correlation between dysplasia and mutations of six tumor suppressor genes in Barrett's esophagus.

Abstract Background . Barrett's esophagus (BE) may progress to adenocarcinoma through dysplastic progression. Classification of dysplasia in BE has significant interobserver variability. Our objective was to determine whether genetic alterations in BE correlate with degrees of histologic dysplasia. Methods . Fixed tissue from 37 patients with BE and adenocarcinoma was studied for six tumor suppressor genes. Tissues were microdissected and analyzed for loss of heterozygosity. Microdissection of individual crypts showing metaplasia and dysplasia were performed and analyzed for 23 of the 37 patients whose tumors were heterozygous for at least four of the six genes studied. Results . Frequency of alterations for MXI1, hOGG1, p53, MTS1, DCC, and APC were 7 of 32 (22%), 12 of 35 (34%), 12 of 26 (46%), 17 of 30 (57%), 17 of 27 (63%), and 23 of 36 (64%), respectively. Analysis of BE demonstrated that crypts with metaplasia, low-grade dysplasia, and high-grade dysplasia strongly correlated with alterations in tumor suppressor genes ( p Conclusions . This pilot study demonstrates that genetic analysis can be performed on individual crypts in patients with BE, and that alterations may facilitate objective classification of the severity of dysplasia.
Seasonal diets of insectivorous birds using canopy gaps in a bottomland forest

Little is known about how insectivorous bird diets are influenced by arthropod availability and about how these relationships vary seasonally. We captured birds in forest-canopy gaps and adjacent mature forest during 2001 and 2002 at the Savannah River Site in Barnwell County, South Carolina, and flushed their crops to gather information about arthropods eaten during four periods: spring migration, breeding, postbreeding, and fall migration. Arthropod availability for foliage- and ground-gleaning birds was examined by leaf clipping and pitfall trapping. Coleopterans and Hemipterans were used by foliage- and ground-gleaners more than expected during all periods, whereas arthropods in the orders Araneae and Hymenoptera were used as, or less than, expected based on availability during all periods. Ground-gleaning birds used Homopterans and Lepidopterans in proportions higher than availability during all periods. Arthropod use by birds was consistent from spring through fall migration, with no apparent seasonal shift in diet. Based on concurrent studies, heavily used orders of arthropods were equally abundant or slightly less abundant in canopy gaps than in the surrounding mature forest, but bird species were most frequently detected in gaps. Such results suggest that preferential feeding on arthropods by foliage-gleaning birds in gap habitats reduced arthropod densities or, alternatively, that bird use of gap and forest habitat was not determined by food resources. The abundance of arthropods across the stand may have allowed birds to remain in the densely vegetated gaps where thick cover provides protection from predators.
Human ultrasonic speech perception

Bone-conducted ultrasonic hearing has been found capable of supporting frequency discrimination and speech detection in normal, older hearing-impaired, and profoundly deaf human subjects. When speech signals were modulated into the ultrasonic range, listening to words resulted in the clear perception of the speech stimuli and not a sense of high-frequency vibration. These data suggest that ultrasonic bone conduction hearing has potential as an alternative communication channel in the rehabilitation of hearing disorders.
Transcriptional and epigenetic regulation of B cell development.

B cell development starts in the bone marrow where hematopoietic stem cells (HSCs) progress through sequential developmental stages, as it differentiates into a naive B cell expressing surface immunoglobulin. In the periphery, B cells that encounter antigen can further differentiate into antibody-secreting plasma cells. In this review, we focus on two factors, E47 and ELL2, which play important roles in the regulation of B cell development in the bone marrow and differentiation of mature B cells into plasma cells in the periphery, respectively. First, E47 activity is required for B cell development in the bone marrow. In addition, we have identified a cell-intrinsic role for E47 in regulating efficient self-renewal and long-term multilineage bone marrow reconstitution potential of HSCs. Second, we explored the role of transcription elongation factors in the super elongation complex (SEC), including ELL2 (eleven-nineteen lysine-rich leukemia factor) in driving poly(A) site choice and plasma cell development. We found that elongation factors impel high levels of IgH mRNA production and alternative processing at the promoter proximal, secretory-specific (sec) poly(A) site in plasma cells by enhancing RNA polymerase II modifications and downstream events. The sec poly(A) site, essentially hidden in B cells, is found by SEC factors in plasma cells.
Performance Criteria for Evaluating Economic Development Potential: An Operational Approach

This paper considers the problem of devising relatively objective criteria, based on past performance, for selecting underdeveloped countries with immediate development potential. The question is of practical importance to foreign aid policy, since those countries which are most rapidly adapting their economic and sociopolitical organization in a direction favorable to economic development are also those in which the economic productivity of foreign capital transfers is likely to be highest. Our concern, then, is with criteria for identifying a set of promising countries as potential foreign aid recipients. In principle, two kinds of approaches can be used to study this question. The first starts from a theoretical model of the development process, estimates it statistically, and then, by analytical methods or sensitivity studies, finds those combinations of values of the relevant parameters which correspond to stagnation, moderate growth, and good growth performance. Each country is then assigned to that group which its parameter combination most closely approximates. This is the essence of the approach used in Chenery and Strout, "Foreign Assistance and Economic Development." 1 The second approach is more empirical in nature. It determines statistically by an analysis of variance, those linear combinations of country performance characteristics which best discriminate among various groups of countries.2 The sense in which the derived functions discriminate best among groups is that they represent those linear combinations of characteristics, each of which, seriatim (given * The authors are indebted to Frank Adelman, George Dalton, and Jonathan Hughes for valuable comments, and to Donald Morrison for the computer program which was used in these computations. The work was financed by NSF grant GS-1235.
Performance of Wideband Digital Receivers in Jamming

Advances in analog-to-digital conversion and digital signal processing may allow new wideband receiver architectures to be built. For example, a receiver could sample a much wider bandwidth than is needed for a single user to communicate. This wideband receiver might be able to simultaneously demodulate the signals of multiple users that occupy different subbands. If a transmitted signal uses frequency hopping, the receiver could generate useful side information for the decoding process by continually monitoring the level of interference in all subbands. Because the analog-to-digital converter (ADC) has finite resolution and operates over a limited range, it is possible that a strong signal can prevent weaker ones from being reliably captured. If multiple users are communicating, this interference may be caused by the near/far problem. However, a jammer can also attempt to disrupt communication by taking advantage of the ADC's limitations. Because of the receiver's wide bandwidth, the jammer might not even need to occupy a frequency subband used by the signal of interest. Instead, it might only transmit in the much wider band sampled by the receiver with sufficiently high power to overload the ADC. The susceptibility of wideband digital receivers to jammers attacking their ADCs will be considered. Receiver implementation and signaling techniques to reduce the effectiveness of this jamming threat will also be examined.
Specification of sense-organ identity by a Caenorhabditis elegans Pax-6 homologue

The Pax-6 transcription-factor gene, containing a paired domain and a paired-type homeodomain, is conserved in structure and ubiquitously present among Metazoa. It is required for development of the central nervous system, and is mutated in human aniridia, mouse and rat small eye and Drosophila eyeless. We identified the Pax-6 gene of the nematode Caenorhabditis elegans in genetic studies of male tail morphology. C. elegans Pax-6 encodes at least two independent genetic functions. One, like other Pax-6 genes, contains paired and homeodomains; this constitutes the genetic locus vab-3. The other, described here, is expressed from an internal promoter and contains only the homeodomain portion; this constitutes the genetic locus mab-18. The mab-18 form of the gene is expressed in a peripheral sense organ and is necessary for specification of sense-organ identity. Its function in this context could be to regulate the expression of cell recognition and adhesion proteins required for sense-organ assembly.
Optical properties of CsI(Na) and heat-treated pure CsI

Abstract On the basis of the similarity of luminescence properties of CsI(Na) crystals and heat-treated crystals of pure CsI excited in the long wavelength tail of the fundamental absorption, the effect of sodium in CsI(Na) is tentatively explained.
Absence of higher-order corrections to low-energy theorems in non-abelian gauge theories

Abstract Using the renormalization group approach, we present a new proof for the absence of higher-order corrections to the low-energy theorem for the matrix element of the divergence of the axial-vector current between the vacuum and two-photon states in spontaneously broken gauge theories.
The Diagnosis and Treatment of Tardive Disorders

Abstract Drugs that block dopamine receptors (dopamine receptor blocking agents; DRBA) may cause a variety of movement disorder syndromes. Among these syndromes are the tardive disorders, which are characterized by an onset weeks to years after the start of DRBA therapy and persist or even worsen after DRBA discontinuation. The tardive disorders may sometimes be permanent. The most common tardive disorders are oral–buccal–lingual dyskinesia, tardive dystonia, and tardive akathisia. The clinical characteristics and treatment of these syndromes are reviewed. Initial evaluation of a patient with a tardive disorder should focus on whether the offending DRBA may be discontinued, and whether the symptoms are severe enough to warrant symptomatic therapy. If it is necessary to continue antipsychotic therapy, consideration should be given to the novel antipsychotic clozapine, which does not cause tardive syndromes and may even ameliorate them. In general, the dopamine depletors reserpine and tetrabenazine are the most effective agents in the symptomatic treatment of the tardive syndromes. Other medications used in the treatment of the tardive syndromes are also reviewed.
Unusual elevation of IgE levels during childhood

IgE levels in children 5 to 15 years of age were much higher than in their parents. The high IgE levels may result in part from a compensation for low IgA levels in children and in part from intestinal infestations.
Apparent drug resistance in epilepsy

To elucidate possible sources of error in the assessment of drug-resistant epilepsy questionnaires were sent, at least one year after hospital discharge, to 259 patients hospitalized between 1. 1. and 31. 12. 1986 because of epilepsy. Information thus obtained included whether and what seizures had occurred after discharge and what drugs had been taken. Answers were received from 173 patients (67%). They revealed that 18 patients (12 men and 6 women; mean age 29.6 [16-58] years) had, before hospitalization, been wrongly thought to have epilepsy resistant to antiepileptic drugs, significantly more often (P less than 0.05) those with generalized epilepsy (21.2%) than with focal seizures (7.4%) or those with both generalized and focal attacks (9.4%). In five patients increasing the dosage of a drug currently taken stopped the seizures. In 12 patients at least one new drug was introduced, in seven of them as a differentiated choice guided by type of seizure and kind of epilepsy. In 11 of these patients the dosage of other drugs could be reduced or the drug discontinued altogether. In one woman seizures stopped after clonazepam had been discontinued. With two exceptions (mesuximide) success was achieved with just one of five standard antiepileptic drugs or by individually determined combinations of them. These results indicate that even in apparent drug resistance absence from seizures can be achieved in many cases of epilepsy if treatment strictly follows accepted principles.
Following homology in singularly perturbed systems

Abstract The fast systems associated to a system of first-order equations where a small parameter multiplies the derivatives (hereinafter, an SPMD system) are obtained by stretching time by a factor of one over the small parameter and then reducing the small parameter to zero. Curves of isolated invariant sets associated to the fast system serve as approximate solutions to the SPMD system over finite intervals in the following sense: A manifold of initial points representing non-zero homology α in the Morse-Conley index of the invariant set at the left endpoint has a submanifold which is carried by the flow of the SPMD system to a manifold representing that non-zero homology class in the index of the invariant set at the right endpint which is the continuation of α along the curve of invariants sets. This is a type of linearization of the approximation problem since the continuation of homology classes along the curve of invariant sets is given by a linear transformation which varies functorially with the curve of invariant sets. Examples are given for systems in R 2 and R 3 . The results are used elsewhere to prove existence theorems for two point boundary value problems to obtain solutions with boundary and interior transition layers.
Peristomal pyoderma gangrenosum and inflammatory bowel disease

Pyoderma gangrenosum (PG) is a debilitating skin disease most often associated with inflammatory bowel disease and is a reportedly rare cause of peristomal ulceration. The lesions of PG rapidly evolve from small, erythematous pustules to deep, painful, pyogenic ulcers within hours to days of onset. Although the behavior and the appearance of the lesions of peristomal PG are diagnostic, a lack of familiarity with PG often leads to misdiagnosis and inappropriate therapy. This study reports four cases of peristomal PG and discusses the 20 previously reported cases in patients with inflammatory bowel disease. Seventy-five percent of patients were female and 67% had Crohn's disease. All patients had colitis, including all of the patients with Crohn's disease, 82% of whom had additional perineal complications. The diagnosis of peristomal PG was based on clinical appearance alone in 83% of cases. The onset of peristomal PG ranged from 2 weeks to 3 years following ostomy. The response to medical therapy was variable. All cases (17 of 17) treated with high-dose corticosteroids and local wound care responded, but five cases required additional therapy. No patient was successfully treated with stoma revision. Risk factors for the development of peristomal PG include Crohn's colitis, female gender, and perineal disease. While most patients respond well to systemic steroids and local wound care, up to one third of patients require long-term medical management. (Arch Surg. 1994;129:769-772)
Somatosensory-Evoked Potentials During Aortic Coarctation Repair

Objective: To determine the incidence of somatosensoryevoked potential (SSEP) changes and the interventions based on these changes during aortic coarctation repair. Design: Retrospective review. Setting: Single-institution, university hospital. Participants: Eighty-four children who had undergone surgical repair of aortic coarctation from January 1984 to May 1996. Interventions: SSEPs were monitored in all patients throughout the procedure. A persistent decrease in amplitude greater than 50% from baseline was considered significant. Duration of SSEP changes in relation to the time course of surgical repair and whether a surgical or anesthetic intervention resulted from a change in SSEPs were documented. Measurements and Main Results: Eighty-four patients underwent 87 surgical procedures. SSEP changes occurred in 40% of the procedures: 38.5% with repair and 15% with test clamp, with 9% occurring during both test clamp and repair. Interventions, which included repositioning the aortic crossclamp, elevating blood pressure, and aborting surgery, occurred in 26.4% of all procedures based on SSEP changes. No patient sustained a neurologic deficit. Conclusion: This is the largest series to date describing the use of SSEPs in aortic coarctation repair. These SSEP changes were often immediately amenable to changes in surgical and anesthetic management. SSEP changes and interventions based on these changes occurred with a considerable frequency.
Light field rendering

A number of techniques have been proposed for flying through scenes by redisplaying previously rendered or digitized views. Techniques have also been proposed for interpolating between views by warping input images, using depth information or correspondences between multiple images. In this paper, we describe a simple and robust method for generating new views from arbitrary camera positions without depth information or feature matching, simply by combining and resampling the available images. The key to this technique lies in interpreting the input images as 2D slices of a 4D function the light field. This function completely characterizes the flow of light through unobstructed space in a static scene with fixed illumination. We describe a sampled representation for light fields that allows for both efficient creation and display of inward and outward looking views. We hav e created light fields from large arrays of both rendered and digitized images. The latter are acquired using a video camera mounted on a computer-controlled gantry. Once a light field has been created, new views may be constructed in real time by extracting slices in appropriate directions. Since the success of the method depends on having a high sample rate, we describe a compression system that is able to compress the light fields we have generated by more than a factor of 100:1 with very little loss of fidelity. We also address the issues of antialiasing during creation, and resampling during slice extraction. CR Categories: I.3.2 [Computer Graphics]: Picture/Image Generation — Digitizing and scanning, Viewing algorithms; I.4.2 [Computer Graphics]: Compression — Approximate methods Additional keywords: image-based rendering, light field, holographic stereogram, vector quantization, epipolar analysis
Husserl's theory of wholes and parts and the methodology of nursing research

Abstract Whenever the name Edmund Husserl appears in the context of nursing research, what correctly comes to mind is the phenomenological approach to qualitative methodology. Husserl is not only considered the founder of phenomenology, but his broad concept development also contributed to the demise of positivism and inspired fruitful approaches to the social sciences. In this spirit of inspiration, it must be expressed that Husserl's theory of wholes and parts, and particularly his differentiation of parts into ‘pieces’ and ‘moments’, is very helpful in guiding the selection of research methods across the board in nursing science. The purpose of this paper is to highlight a frame of reference for nursing researchers to use in examining the essential nature of that which is being studied. This frame of reference is the Husserlian philosophy of ‘pieces’ and ‘moments’ in relation to the whole. ‘Pieces’ are independent parts of the whole that are subject to isolability in study, whereas ‘moments’ are nonindependent parts, which cannot be detached, presented, or studied apart from the whole. The intent is to propose this frame of reference as a philosophical base from which nursing researchers may better select among paradigms and methodological approaches in regard to the essential nature (‘pieces’ or ‘moments’) of that which they are researching.
Childhood injuries in the United States. Mortality, Morbidity, and cost.

• National estimates of the mortality, morbidity, and cost of childhood injuries are presented by specific causes. Motor vehicle–related inuries, homicide, and suicide are the leading causes of childhood injury deaths. Falls and sports-related injuries are the leading causes of hospitalizations and emergency department visits. We estimate that unintentional childhood injuries cost the nation $7.5 billion in 1982. The highest direct costs per year for unintentional injuries are attributable to falls, sports, and motor vehicle occupant injuries, while the highest indirect costs are related to motor vehicle occupant injuries, pedestrian injuries, and drowning. Injury accounts for 78% of the total fatalities among late adolescents (age 15 to 19 years), the pediatric age group at highest risk for injury mortality. A stronger federal and state commitment is needed to prevent childhood injury. (AJDC.1990;144:649-652)
Interpersonal emotion regulation as a mechanism of social support in depression

Although social support is widely considered to be protective against depression, the mechanisms through which it acts on depressive psychopathology are not well known. This integrative review argues that emotion regulation serves as such a mechanism. First, the literature on the effects of social support on depression is reviewed, with an emphasis on open empirical questions regarding mechanisms linking support and depression. Then, the literature on emotion regulation is reviewed, highlighting its importance as a mechanism in the psychopathology of depression. Finally, potential interpersonal influences on depressive emotion regulation and dysregulation are suggested, drawing from theory and research on psychotherapy and on close relationships. The review suggests that emotion regulation is responsive to interpersonal influences, and that this responsiveness may account for the effects of social support on depression. Implications of an interpersonal perspective for basic and clinical research on depression, close relationships, and emotion regulation are discussed.
Immunohistochemical mapping of galanin-like neurons in the rat central nervous system

Using an antiserum generated in rabbits against synthetic galanin (GA) and the indirect immunofluorescence method, the distribution of GA-like immunoreactive cell bodies and nerve fibers was studied in the rat central nervous system (CNS) and a detailed stereotaxic atlas of GA-like neurons was prepared. GA-like immunoreactivity was widely distributed in the rat CNS. Appreciable numbers of GA-positive cell bodies were observed in the rostral cingulate and medial prefrontal cortex, the nucleus interstitialis striae terminalis, the caudate, medial preoptic, preoptic periventricular, and preoptic suprachiasmatic nuclei, the medial forebrain bundle, the supraoptic, the hypothalamic periventricular, the paraventricular, the arcuate, dorsomedial, perifornical, thalamic periventricular, anterior dorsal and lateral thalamic nuclei, medial and central amygdaloid nuclei, dorsal and ventral premamillary nuclei, at the base of the hypothalamus, in the central gray matter, the hippocampus, the dorsal and caudoventral raphe nuclei, the interpeduncular nucleus, the locus coeruleus, ventral parabrachial, solitarii and commissuralis nuclei, in the A1, C1 and A4 catechaolamine areas, the posterior area postrema and the trigeminal and dorsal root ganglia. Fibers were generally seen where cell bodies were observed. Very dense fiber bundles were noted in the septohypothalamic tract, the preoptic area, in the hypothalamus, the habenula and the thalamic periventricular nucleus, in the ventral hippocampus, parts of the reticular formation, in the locus coeruleus, the dorsal parabrachial area, the nucleus and tract of the spinal trigeminal area and the substantia gelatinosa, the superficial layers of the spinal cord and the posterior lobe of the pituitary. The localization of the GA-like immunoreactivity in the locus coeruleus suggests a partial coexistence with catecholaminergic neurons as well as a possible involvement of the GA-like peptide in a neuroregulatory role.
Response to Comment by W.A. Myers and P.K. Kuroda on “Actinide abundances in ordinary chondrites”

One aspect of our recent paper (HAGEE et al., 1990) on actinide abundances in ordinary chondrites is estimation of the amount of ^(244)Pu present in these meteorites at the time of their formation. This estimate is based on the quantity of ^(244)Pu spontaneous fission Xe, a component whose resolution from other Xe components present must be based on observed isotopic compositions in the meteorite and assumed compositions for the contributing components. In their comments, MYERS and KURODA (1991) advocate a different approach to component analysis of Xe than the one we used and arrive at correspondingly different estimates of fission Xe and ^(244)Pu abundances.