cssi/SciSciGPT-SciSciNet huggingface dataset:
Current diagnosis and management of Zollinger-Ellison syndrome.

The treatment of patients with Zollinger-Ellison syndrome (ZES) has undergone dramatic evolution during the past decade. Although initially regarded as an incurable tumor, resection of gastrinoma for potential cure has been reported in 30% to 40% of selected patients in recent series. Conversely, although definitive control of acid hypersecretion is achieved by total gastrectomy, histamine (H2)-receptor antagonists and the newly introduced agents omeprazole and somatostatin analogues allow effective medical therapy of gastric acid overproduction. Confirmation of the diagnosis is best achieved with the I.V. secretin stimulation test, and tumor localization techniques are mandatory to identify candidates for operative tumor resection. Intraoperative sonography and careful exploration are required for tumor removal; successful tumor resection is associated with prolonged survival. The majority of patients (60%) are still found to have malignant disease at the time of diagnosis, but 10-year overall survival commonly exceeds 40%. The presence of multiple endocrine neoplasia type I (MEN-I) is seen in 10% to 25% of patients; correction of hypercalcemia alone may have therapeutic benefit in some ZES patients, and while gastrinoma resection is rarely possible, MEN-I patients demonstrate prolonged survival. The choice of medical rather than surgical therapy for acid hypersecretion depends on the suitability of each patient for careful and repeated endoscopic and chemical studies, versus the likelihood of a successful postoperative outcome. Socioeconomic, geographic, and related medical factors in each case may dictate the form of long-term antisecretory therapy. Exploration for possible tumor resection is indicated for virtually all patients who have no documented metastatic disease.
One Hundred Years of Labor Control: Violence, Militancy, and the Fairtrade Banana Commodity Chain in Colombia:

This paper explores the role of Fairtrade certification in mediating banana production relations in Uraba, Colombia. While the country has long been incorporated into the world banana economy, the region's fraught history of dispossession, exploitation, and resistance make it a useful site through which to consider its more recent articulation into the Fairtrade banana commodity chain. In some respects, the emergence of Fairtrade in Uraba could be framed as a win–win. Banana growers have enrolled in certified commodity chains as a way to add value, stabilize their position in a volatile global market, and bring additional resources to workers. However, Fairtrade's role in reframing Uraba as a site of ethical banana production has been contingent upon multiple forms of marginalization and devaluation, expressed in their most extreme form through an armed conflict that swept the region during the last two decades of the 20th century. Fieldwork conducted with banana workers and growers in Uraba suggests that...
Comment on "Quasiclassical transport at a van Hove singularity in cuprate superconductors"

A Comment on the Letter by D. M. Newns, et al., Phys. Rev. Lett. 73, 1695 (1994). The authors of the Letter offer a Reply.
Opening wedge trapezial osteotomy as possible treatment for early trapeziometacarpal osteoarthritis: a biomechanical investigation of radial subluxation, contact area, and contact pressure.

Purpose Radial subluxation and cartilage thinning have been associated with initiation and accelerated development of osteoarthritis of the trapeziometacarpal joint. Few investigators have reported on the benefits of opening wedge trapezial osteotomy for altering the contact mechanics of the trapeziometacarpal joint as a possible deterrent to the initiation or progression of osteoarthritis. We used cadaveric specimens to determine whether opening wedge osteotomy of the trapezium was successful in reducing radial subluxation of the metacarpal base and to quantify the contact area and pressure on the trapezial surface during simulated lateral pinch. Methods We used 8 fresh-frozen specimens in this study. The flexor pollicis longus, abductor pollicis longus, adductor pollicis, abductor pollicis brevis, and flexor pollicis brevis/opponens pollicis tendons were each loaded to simulate the thumb in lateral pinch position. We measured radial subluxation from anteroposterior radiographs before and after placement of a 15° wedge. We used real-time sensors to analyze contact pressure and contact area distribution on the trapezium. Results Center of force in the normal joint under lateral pinch loading was primarily located in the dorsal region of the trapezium. After wedge placement, contact pressure increased in the ulnar-dorsal region by 76%. Mean contact area increased in the ulnar-dorsal region from 0.05 to 0.07 cm 2 , and in the ulnar-volar region from 0.003 to 0.024 cm 2 . The average reduction in joint subluxation was 64%. Conclusions The 15° opening wedge osteotomy of the trapezium reduced radial subluxation of the metacarpal on the trapezium and increased contact pressure and contact area away from the diseased compartments of the trapezial surface. Trapezial osteotomy addresses the 2 preeminent theories about the initiation and progression of osteoarthritis. Clinical relevance By reducing radial subluxation and altering contact pressure and contact area, trapezial osteotomy may prove an alternative to first metacarpal extension osteotomy or ligament reconstruction in early stages of degenerative arthritis of the trapeziometacarpal joint.
Dispersion-Relation Fluorescence Spectroscopy

Because of its ability to study specifically labeled structures, fluorescence microscopy is the most widely used technique for investigating live cell dynamics and function. Fluorescence correlation spectroscopy is an established method for studying molecular transport and diffusion coefficients at a fixed spatial scale. We propose a new approach, dispersion-relation fluorescence spectroscopy (DFS), to study the transport dynamics over a broad range of spatial and temporal scales. The molecules of interest are labeled with a fluorophore whose motion gives rise to spontaneous fluorescence intensity fluctuations that are analyzed to quantify the governing mass transport dynamics. These data are characterized by the effective dispersion relation. We report on experiments demonstrating that DFS can distinguish diffusive from advection motion in a model system, where we obtain quantitatively accurate values of both diffusivities and advection velocities. Because of its spatially resolved information, DFS can distinguish between directed and diffusive transport in living cells. Our data indicate that the fluorescently labeled actin cytoskeleton exhibits active transport motion along a direction parallel to the fibers and diffusive in the perpendicular direction.
1723 INCREASED VENTILATORY DRIVE AND IMFROVED LOAD COMPENSATION WITH CAFFEINE THERAPY

To evaluate the effect of caffeine therapy (CT) on ventilatory response of growing preterm infants to a combined inspiratory and expiratory resistive load (R), 6 infants were studied before and during CT. Mean ± SEM, BW=1730±58gm, GA=32.7±0.8 wks, study age=22.3±4.9 wks, study weight=2231±132gm, CT level=10.0±1.3 mg/dl. These infants had no lung disease at birth. Pulmonary mechanics (dynamic lung compliance, inspiratory and expiratory resistance, and total pulmonary resistance) were normal at the time of study. Pulmonary measurements: tidal volume (VT), respiratory frequency (f), minute ventilation (MV), peak inspiratory flow (VI), peak expiratory flow (VE), inspiratory time/total respiratory time (TI/TT), and esophageal pressure (Pes) were obtained before and 60 sec after the application of R. A variable resistor was used to administer a separate load of 50 (R1) and 100 (R2) cm H2O/L/sec. Mean ± SEM control values were VT=7.6±0.9ml/kg, f=66.4±6.1 breaths/min, MV=491. 7±65. 2ml/min/kg, TI/TT=0.47±0.01, VI=3.10± 0.57L/min, VE=2.61±0.52L/min, Pes=8.4± 1.2cm H2O. Application of R1 and R2 resulted in an increase in Pes which is a measure of respiratory drive. This response was significantly greater (p<.05) during CT. Furthermore, there was no change in VT during CT, which significantly decreased with application of R prior to therapy. These data demonstrate that CT is associated with increased ventilatory drive and improved load compensation.
Testing and verifying concurrent objects

Abstract A concurrent object is a data structure shared by concurrent processes. We present a two-pronged approach for establishing the correctness of implementations of concurrent objects. Our approach is based on a notion of correctness called linearizability : each concurrent object has a sequential specification, which describes how it behaves in sequential executions. Each concurrent execution is required to be equivalent to some sequential execution. We advocate using both testing and verification as complementary approaches for showing a concurrent object is linearizable. We first describe a simulation environment for simulating, testing, and analyzing implementations of concurrent objects. We can use the simulator to gain assurance that an implementation is correct or to detect errors in an incorrect one. The simulator provides a systematic way to testing implementations of any data type. Whereas testing is useful in practice, verification is more definitive. We provide a library of verified concurrent objects; specifically, we give the specifications, implementations, and proofs of correctness for the FIFO queue, semiqueue, and stuttering queue data types. Implementors of objects of other data types can use our library by following the patterns of design and proof that we give; at the same time, clients of our library need not reimplement commonly used abstractions from scratch and are freed from the tedium of their verification.
The Number of Real Zeros of the Single Parameter Mittag-Leffler Function for Parameter Values Between 1 and 2

The single parameter Mittag-Leffler function, which is a generalization of the exponential function, occurs naturally in the solution of physical problems involving fractional calculus and its zeros play a significant role in the dynamic solutions. It is known that the Mittag-Leffler function has a finite number of real zeros in the range of parameter values between 1 and 2, which is quite relevant for many physical problems. However, the number of real zeros for a given parameter value in this range is not known. An iteration formula for calculating the number of real zeros of the Mittag-Leffler function for any value of the parameter in the range between 1 and 2 is presented.Copyright © 2005 by ASME
The Forgotten Minorities: Health Disparities of the Lesbian, Gay, Bisexual, and Transgendered Communities

Iwoke up early that morning for an appointment with my primary care provider; I did not want to be late because I was a new patient and had waited a month for the appointment. Since I had moved across town to attend college, it was no longer feasible to go to my long-time primary care provider (PCP). Although seeing a new PCP made me slightly apprehensive, I had no idea that I would leave the physician’s office feeling ashamed. The office seemed like any other office—pamphlets about women’s health were displayed in a holder attached to the wall, there were comfortable chairs for waiting, and magazines were lying on a table ready for perusal. The receptionist at the front desk was friendly and welcoming. At check-in, I began to describe my medical history on a patient intake form that listed the typical medical questions that one would expect. Then I reached the section of the intake form that requested demographic information. One question asked for “Current relationship status” and the response options were: Single; Married; and Widowed. I didn’t fit any of those descriptions. I also noticed the omissions of questions concerning sexual orientation and gender identity. Thus, I checked the box for single despite my two-year long relationship with my partner. When the nurse led me to the exam room to assess my vital signs, she made small talk and we laughed a little, which made me slightly more comfortable. When the PCP came into the room, she introduced herself and shook my hand. We reviewed the information in my intake form together and everything seemed straightforward until she asked me if I was sexually active. I told her that I was, to which she replied, “Would you like birth control?” When I told her that I didn’t need it, she proceeded to tell me about unwanted pregnancy and the benefits of birth control, even though I did not request this information. She asked, “So, are you using protection to prevent pregnancy?” I simply said, “I don’t have sex with men.” That statement was met with a long pause as she just stared at me. The moment seemed to linger forever and I did not know which of us was more uncomfortable. “So, you’re a lesbian?” she asked, to which I quickly replied, “I’m gay.” I suddenly felt embarrassed. She sighed deeply as if to indicate that what I had just
A retinoic acid-inducible skin-specific gene (RIS-1/psoriasin): molecular cloning and analysis of gene expression in human skin in vivo and cultured skin cells in vitro

A retinoic acid (RA) inducible skin-specific gene transcript (RIS-1) was isolated by differential hybridization screening of a RA-treated human skin cDNA library. The library was constructed from pooled RNA derived from normal adult human skin treated with all trans-RA for 4 h (n = 6) and 12 h (n = 6) in vivo. RIS-1 cDNA corresponded to a 0.6 kb transcript that was barely detectable in normal adult human skin but was significantly induced by 8 h in RA-treated compared to vehicle-treated skin (range 1.1-3.6 fold). Prolonged RA treatment for up to 24 h further increased relative RIS-1 mRNA levels by 1.3-5.5 fold. HPLC analysis of the RA content of 0.1% RA-treated skin in vivo revealed significant levels at 6 h (18.8-120.6 ng RA/g wet weight tissue; approximately 240 nM), immediately preceding the time point at which the increased RIS-1 mRNA level was first seen. This concentration of RA also induced the mRNA levels for cellular RA binding protein II (1.6-19 fold), a marker of RA activity in human skin. RIS-1 mRNA was detected by Northern and dot blotting only in normal skin but not in any other normal human tissues examined, indicating a tissue-specific pattern of gene expression. RIS-1 transcripts were detected at very low levels in untreated cultured human epidermal keratinocytes, while no expression was seen in dermal fibroblasts and melanocytes, the other major cell types in skin. Southern analysis of human and mouse DNA indicated the existence of evolutionarily conserved sequences for RIS-1 between these two species. The polypeptide sequence derived from the partial RIS-1 cDNA was found to be identical to the calcium binding domain found in 'psoriasin', a gene whose expression appears to be increased in the skin of psoriasis patients.
Elastic percolation models for cohesive mechanical failure in heterogeneous systems

We introduce a class of models for microstructural damage and cohesive macromechanical failure in heterogeneous systems. Our models are based on random networks of Hooke-type springs with load limit, such that a spring breaks irreversibly if stretched beyond a critical length ${u}_{c}$. We consider several special cases in which both the spring constant $k$ and ${u}_{c}$ are distributed quantities, and we show that the macroscopic response of the system depends crucially on the form of the probability distribution functions (PDF's) for $k$ and ${u}_{c}$. If the first inverse moment of the PDF is finite, it appears that macromechanical failure occurs by means of a sharp transition, in which a single crack spans the entire system ("brittle failure"). By contrast, if the first inverse moment is infinite, many cracks appear in the system. Then, at a certain microdamage level, as defined by the fraction of broken springs, all moduli of the system vanish ("pseudobrittle failure") and the system undergoes a percolationlike transition.
The effect of pH in intensive microalgal cultures. I. Biomass regulation

Two freshwater and two marine algal species were grown in intensive continuous cultures at a fixed dilution rate of 0.5 day −1, but at varying pH levels in the range 7.6 to 10.6. Both freshwater species, Scenedesmus obliquas (Turp.) Kutz. and Chlorella vulgaris Beij., grew up to pH 10.6 although C. vulgaris was more adversely affected by alkaline pH than was Scenedesmus obliquas. Of the marine species, Phaeodactylum tricornutum (TFX-1) Bohlin was hardly affected by varying pH up to its maximum tolerable level of 10.3, whereas growth of Dunaliella tertiolecta (Dun) Butcher was adversely affected by increasing pH and ceased when the pH exceeded 9.3. These results are consistent with the general observations that many marine species cannot tolerate alkaline pH values much above 9.5. Moreover, the unique ability of Phaeodactylum tricornutum to grow at pH > 10 probably is a major factor contributing to its well documented success in large-scale outdoor cultures that are poorly buffered. It is difficult to separate metabolic from purely chemical factors that influence the pH tolerance limits of the individual species. The lower pH limits were, however, distinctly controlled by the production of alkalinity concomitant with NO−3 uptake, whereas the upper pH limits in the case of Scendesmus obliquus and Phaeodactylum tricornutum seemed to be regulated primarily by metabolic control. In no case was the availability of inorganic carbon an influencing factor in setting the maximum attained pH.
Minimization of Degradation Through Prognosis Based Control for a Damaged Aircraft Actuator

In this paper we present a formulation of an aircraft systems model for prognosis-based control. An aircraft systems model with hydraulic actuators for control surfaces is developed in SIMULINK and is connected with a model for predicting degradation of an actuator. An LQR based feedback control is employed to compensate for changes in the plant dynamics and a feedforward controller is used to achieve better performance through set-point tracking, while taking into account the current actuator degradation rate. The advantage of the combination of feedback and feedforward control strategies is then demonstrated through reduction of degradation of the actuator while achieving a minimum loss of performance using constrained optimization.Copyright © 2009 by ASME
The effect of increasing the response rate in S1 and S2 on stimulus generalization and the peak shift

In the present study it was found that differentially increasing the response rate in both S1 and S2 by changing from Mult VI 5- VI 5-min reinforcement schedule to Mult VI 1- VI 3-min schedule produced a peak shift in five of six pigeons. The results suggest that a change in reinforcement density independent of a response rate reduction in S2 is a sufficient condition to produce the peak shift.
A new simulation method for the determination of forces in polymer/colloid systems

We introduce a new simulation method, which we call the contact-distribution method, for the determination of the Helmholtz potential for polymer/colloid systems from lattice Monte-Carlo simulations. This method allows one to obtain forces between finite or semi-infinite objects of any arbitrary shape and dimensions in the presence of polymer chains in solution or physisorbed or chemisorbed at interfaces. We illustrate the application of the method using two examples: (i) the interaction between the tip of an atomic force microscope (AFM) and a single, end-grafted polymer chain and (ii) the interaction between an AFM tip and a polymer brush. Numerical results for the first two cases illustrate how the method can be used to confirm and extend scaling laws for forces and Helmholtz potentials, to examine the effects of the shapes and sizes of the objects and to examine conformational transitions in the polymer chains.
HumaniTech1: A Discipline‐Centered Approach to Technology at UCI

Purpose – To share with readers how HumaniTech evolved and has matured over 18 years.Design/methodology/approach – A description of a programmatic infrastructure that emphases technology in the humanities for teaching and research purposes.Findings – As more institutions define and focus on how technology is driving their disciplines and changing how scholarship is being created, more connections are being made to educate the scholars about opportunities for improved ways to teach, incorporate new resources and methodologies to better define and further their craft. Implementing media to study and capture information is a moving target with new products and technologies being announced often.Research limitations/implications – This visit to HumaniTech does not capture everything but focuses on how technology in the humanities at one institution has addressed the need to raise the bar and share how colleagues are using information in their field and what this may mean for scholarly publishing.Practical imp...
On‐line support groups: An investigation of relationships among source credibility, dimensions of relational communication, and perceptions of emotional support

This study examined perceptions of dimensions of relational communication, source credibility, and emotional support among (N = 94) on‐line support group users. The results indicated there was a positive relationship between emotional support and immediacy, similarity, receptivity and equality. Emotional support were negatively related to dominance, and formality. Finally, perceptions of source credibility were also related to perceptions of emotional support and perceptions of relational communication.
College Students' Reactions To Social Scientific Experimentation

A random sample of undergraduate students were interviewed to study (a) their attitudes about and reactions to social science experiments and (b) the effects such attitudes and reactions may have on the validity of experimental research. It was found that the majority of the respondents had rather definite reactions to experiments, most of them generally favorable. Although the models of subjects and experiments proposed by various writers in the field received some support, none of the models was sufficiently complex to account for the range of responses exhibited by the respondents.
Discrete crosslinked fibrin microthread scaffolds for tissue regeneration.

Received 9 June 2006; revised 11 August 2006; accepted 28 August 2006Published online 31 January 2007 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jbm.a.31057Abstract: In this study, we report on the development ofdiscrete ﬁbrin microthreads as well as novel scaffolds com-posed of arrays of ﬁbrin threads. These scaffolds exhibitmechanical properties that are signiﬁcantly greater thanﬁbrin gels and cellular responses suggesting that the mate-rials are conducive to the development of organized,aligned tissues. Fibrin microthreads were produced bycoextruding solutions of 70 mg/mL ﬁbrinogen and 6 U/mL thrombin through small diameter polyethylene tubing.Uncrosslinked ﬁbrin microthreads averaged 55–65 mminhydrated diameter and achieved ultimate tensile strengthsapproaching 4.5 MPa. The strengths and stiffnesses of themicrothreads were approximately twofold greater whenthe materials were treated with exposure to ultraviolet(UV) light. Although UV crosslinking attenuated ﬁbroblastproliferation, uncrosslinked ﬁbrin microthreads supportedﬁbroblast attachment, proliferation, and alignment, sug-gesting that they represent a viable biomaterial for thealigned regeneration of tissues. Because of the physiologicroles of ﬁbrin matrices in the early phase of wound heal-ing, we anticipate that these ﬁbrin-based microthreads willdirect the spatially and temporally complex processes ofcell-mediated tissue ingrowth and regeneration. 2007Wiley Periodicals, Inc. J Biomed Mater Res 82A: 104–112,2007Key words: ﬁbrin; tissue regeneration; threads; woundhealing
Data envelopment analysis with stochastic data

Data envelopment analysis (DEA) has proven to be a useful technique in evaluating the efficiency of decision making units that produce multiple-outputs using multiple-inputs. However, the ability to estimate efficiency reliably is hampered in the presence of measurement error and other statistical noise. A main and legitimate criticism of all deterministic models is the inability to separate out measurement error from inefficiency, both of which are unobserved. In this paper, we consider panel data models of efficiency estimation. One DEA model that has been used averages cross-sectional efficiency estimates across time and has been shown to work relatively well. In this paper, it is shown that this approach leads to biased efficiency estimates and provide an alternative model that corrects this problem. The approaches are compared using simulated data for illustrative purposes.
Psychiatric Symptoms Associated with Anabolic Steroids: A Controlled, Retrospective Study

AbstractThis investigation characterized the symptom patterns and mental status changes precipitated by anabolic steroid abuse. Twenty male weightlifters who were currently using anabolic steroids were compared to 20 male weightlifters who had never used steroids. The steroid users had significantly (p < 0.005) more somatic, depressive, anxiety, hostility, and paranoid complaints when using steroids than when they were not using the drugs. When contrasted to the weightlifter controls, the steroid users had a significantly (p < 0.005) greater number of complaints of depression, anxiety, and hostility during cycles of steroid use. However, no differences in the frequency of major mental disorders were found between the two groups. It is concluded that the organic affective changes associated with anabolic steroid abuse usually present as a subsyndromal depressive disorder of insufficient severity to be classified as a psychiatric disorder.
Solvated electron: Criticism of a suggested correlation of chemical potential with optical absorption energy☆

Abstract A recent theoretical treatment of the absorption spectrum of the solvated electron, es-, maintains that rigorously μ0 ⩾ -0.75Eav which gives empirical relationship, μ0 ⩾ - (0.93 ± 0.02)Emax. For es- in a particular solvent at a temperature and pressure; μ0, Eav and Emax are standard chemical potential, average energy of the absorption spectrum and the energy at the absorption maximum respectively. The temperature and pressure effects on the absorption spectrum of es- in water and liquid ammonia do not support the equality sign in the above cited relationships. The implications of inequality expressed above are discussed for es- in water and liquid ammonia.
Three-dimensional reconstruction of curves from pairs of projection views in the presence of error I. Algorithms

We have previously described an approach to 3D intracerebral vascular reconstruction that uses an MRA as a reconstruction base. Additional vessels seen only by angiography are added by segmenting 2D curves from projection angiograms and reconstructing these curves into 3D, building upon the MRA. Intracerebral vascular reconstruction is difficult for at least two reasons. First, 2D curves must be associated on projection images even when the human eye cannot do so. Second, 3D curves must be reconstructed in the presence of errors such as misregistration, image distortion, and misdefinition of 2D curves. This paper is the first of two that address the specific issue of reconstruction of a 3D curve from a given pair of 2D curves in the presence of error. The method explicitly separates what can and cannot be determined from a pair of projection views. It is also capable of recognizing interruptions produced by viewplane errors, of continuing reconstruction beyond such interruptions, and of localizing and estimating the magnitude of the interruptions. These measurements can also be used to estimate the lengths of regional disparities between a pair of 2D curves, leading to a quantitative estimate of the capacity of a pair of 2D curves to combine to create a 3D object (match value). Match values can be used, in turn, as part of the strategy for automatically associating pairs of 2D curves. This paper provides methods for reconstructing a given pair of 2D curves into 3D in the presence of error and for calculating match values. Error analysis is given in the companion report.
The Triple Entente and the Triple Alliance 1880–1914: A Collective Goods Approach

The distribution of burdens in alliances may be explained in terms of public and private outputs. A joint product model is applied to the Triple Alliance and Triple Entente, using generalized least squares-auto regressive moving average (GLS-ARMA) techniques and time series data. Results indicate that countries regarded allies' military effort more as complements than as substitutes, though several examples of free-riding behavior are noted. The method used here may provide more accurate estimation of publicness problems than is found in the usual static tests.
Decay of isolated surface features driven by the Gibbs-Thomson effect in an analytic model and a simulation

A theory based on the thermodynamic Gibbs-Thomson relation is presented that provides the framework for understanding the time evolution of isolated nanoscale features (i.e., islands and pits) on surfaces. Two limiting cases are predicted, in which either diffusion or interface transfer is the limiting process. These cases correspond to similar regimes considered in previous works addressing the Ostwald ripening of ensembles of features. A third possible limiting case is noted for the special geometry of {open_quotes}stacked{close_quotes} islands. In these limiting cases, isolated features are predicted to decay in size with a power-law scaling in time: A{proportional_to}(t{sub 0}{minus}t){sup n}, where A is the area of the feature, t{sub 0} is the time at which the feature disappears, and n=2/3 or 1. The constant of proportionality is related to parameters describing both the kinetic and equilibrium properties of the surface. A continuous-time Monte Carlo simulation is used to test the application of this theory to generic surfaces with atomic scale features. A method is described to obtain macroscopic kinetic parameters describing interfaces in such simulations. Simulation and analytic theory are compared directly, using measurements of the simulation to determine the constants of the analytic theory. Agreement between the two is very goodmore » over a range of surface parameters, suggesting that the analytic theory properly captures the necessary physics. It is anticipated that the simulation will be useful in modeling complex surface geometries often seen in experiments on physical surfaces, for which application of the analytic model is not straightforward. {copyright} {ital 1997} {ital The American Physical Society}« less
Modulation of apoptotic signaling pathways to promote survival of endothelial cells by gene therapy

Purpose Corneal transplantation is the most common transplantation worldwide. Surgeons and eye banks face major problems: (1) shortage of tissue in aging populations, (2) loss of high-quality tissue due to cell loss during storage, (3) graft failure. It has been demonstrated that EC loss is mediated by the cells’ intrinsic death machinery resulting in apoptosis. Identification of survival strategies could raise the availability of tissue, with a significant impact on transplantation by lowering graft rejection rate. The purpose of this study different apoptotic pathways and to determine the protective effect of the anti-apoptotic proteins bcl-xL and p35. Methods Intrinsic (mitochondria-mediated) and extrinsic (ligand-mediated) apoptotic pathways were selectively activated to provoke apoptosis of murine and human corneal endothelial cells suspensions and corneas. Gene transfer of bcl-xL or p35 was accomplished, survival of EC was determined by flow cytometry and laser scanning microscopy. Results Interestingly, we were able to determine distinct differences in cell survival enhancement depending on the type of overexpressed protein. Whereas uninfected controls showed significant EC death, gene-therapeutically treated EC demonstrated significantly increased cell survival. We will present data on the efficacy of certain anti-apoptotic proteins in select pathways. Conclusion Exploring inhibitory strategies of EC death can lead to clinically relevant survival strategies with significant impact on corneal grafting.
Microdissection and microcloning of mid-chromosome 4: genetic mapping of 41 microdissection clones.

Available genetic information places the mouse db (diabetes) gene approximately 5 cM distal to Ifa on mid/distal mouse chromosome 4. These data have indicated that there is a relevant paucity of genetic markers that map to this region of chromosome 4. To increase the density of the genetic map on mid-chromosome 4, the authors have applied the techniques of microdissection and microcloning of the mid-portion of mouse chromosome 4. A total of 47 RFLPs from the microdissection library were used to type the progeny of three C57BL/6J Mus spretus backcrosses. The resulting composite genetic map positions seven known genes, 41 microclones, and three other anonymous markers to a region of approximately 21 cM on mid-chromosome 4 extending from b to Lck. The density of markers in this region of chromosome 4 should be sufficient to initiate the physical mapping of this subchromosomal segment, facilitating efforts to clone the db gene, as well as other uncloned mutant loci in this region of chromosome 4. 30 refs., 3 figs., 1 tab.
Object-motion measurements using pulse-echo acoustical speckle and two-dimensional correlation

A basic theory of acoustical speckle and cross-correlation is described which utilizes the ubiquitous wave characteristics in ultrasonics. A computer-based pulse-echo system has been developed. It is interfaced to a VAX11/780 computer which operates the system and performs the data analysis. Data from three tests using specimens of steel, aluminum and Plexiglas are discussed. On each specimen, a pulse-echo scan of a scattering surface is made over some area which represents reference configuration. After the surface is displaced, a pulse-echo scan is made over the same area. A small region of the displaced configuration is correlated with the reference as a measure of object motion.
Gene mediated insulin-like growth factor-I delivery to the synovium.

Abstract The feasibility of articular gene therapy using insulin-like growth factor-I transgene expression in synovial tissues was assessed in vitro by transfection of synovial explant and monolayer cultures. Synovial membrane was harvested from horses and distributed for explant culture in multiwell plates or digested for monolayer culture in multiwell plates and chamber slides. Synovial monolayers were cultured for 48 h after infection with 0, 100, 200, or 500 moi adenovirus-IGF-I (AdeIGF-I) to establish an optimum dose. Explants were then either infected with AdeIGF-I or adenoviral LacZ and cultured for 8 days, treated with 100 ng/ml recombinant IGF-I as a positive control, or remained as uninfected untreated culture controls. Expression of IGF-I in explants and monolayers was assessed by in situ hybridization and quantitative polymerase chain reaction (PCR), and translation confirmed by IGF-I radioimmunoassay (RIA) and tissue immunoreaction. Effects of IGF-I on synovial function was assessed by proteoglycan and hyaluronan assay, and northern blot assessment of decorin and collagen type I expression. Significant transgene expression in synovial cells was present for all AdeIGF-I concentrations. Similarly, medium IGF-I concentrations were significantly elevated in AdeIGF-I infected synovial monolayer and explant cultures at all time points. Peak IGF-I concentration of 246±43 ng/ml developed in explant cultures on day 4; IGF-I levels in control explant groups were unchanged over baseline values. In situ hybridization and immunolocalization for IGF-I indicated focal IGF-I expression in intimal and subintimal layers of infected explants, with diffuse immunoreaction throughout infected subintimal and fibrous layers. For monolayer cultures, intracellular immunoreaction to IGF-I was markedly higher in infected cells, and was most prominent at 100 moi. Effects of IGF-I on synoviocyte cultures were evident on northern blots, which showed decreased decorin expression and elevated type I collagen production in AdeIGF-I infected monolayers. Proteoglycan concentration in the medium from explant cultures rose over the initial 4 days but was similar between treatment groups. The concentration of hyaluronan in medium from explant cultures did not differ significantly within or between treated and control groups during the 8-day study period. These data indicate that IGF-I can be successfully introduced to synovial structures by adenoviral vectors and results in effective IGF-I ligand synthesis without untoward synovial morphologic effects.
Preparation and characterization of metal oxide/polyimide nanocomposites

In an effort to introduce low levels of electrical conductivity into space durable polyimides while maintaining optical clarity, nanocomposites containing metal oxides were prepared and characterized. Polymeric materials that exhibit space environmental durability, high optical transmission, low solar absorptivity and sufficient electrical conductivity for electrostatic charge dissipation are needed for future ultra-lightweight, deployable spacecraft. Samples were prepared by the addition of the metal oxide to a pre-made polyimide solution and by the synthesis of the polyimide in the presence of the metal oxide. Sonication was used to aid in the dispersion of the metal oxide particles in N,N-dimethylacetamide prior to mixing. Thin films were prepared and characterized for thermal and mechanical properties, solar absorptivity, thermal emissivity, electrical conductivity, optical transmission and degree of dispersion of the metal oxide particles. The effect of the metal oxide particles on the polyimide properties will be discussed.
Bioavailability of Reversibly Sorbed and Desorption-Resistant 1,3-Dichlorobenzene from a Louisiana Superfund Site Soil

Microcosm batch studies were conducted to study the biodegradation of 1,3-dichlorobenzene (1,3-DCB) from the aqueous (soil free) and soil phases. For soil phase experiments, a freshly contaminated soil and a soil containing only the desorption-resistant or irreversibly bound or non-labile fraction of the contaminant were used. These experiments were designed to simulate biodegradation at Superfund site assuming sorption/desorption equilibrium was reached. The presence of the soil reduced the rates of biodegradation significantly. Nearly 100% of the total 1,3-DCB in the aqueous phase was biodegraded by enriched bacterial cultures within 7 days compared to about 55% over a 6-week incubation period from the freshly contaminated soil. The biodegradation in the soils containing only the desorption-resistant fraction of the contaminant was considerably lower (about 30%). It is believed that for freshly contaminated soil, 1,3-DCB readily desorbed into the aqueous phase and was available for microbial consumption whereas for soils containing mostly the desorption-resistant fraction of 1,3-DCB, the contaminant availability was limited by the mass transfer into the aqueous phase. Our earlier studies concluded that about 20–30% of the sorbed contaminant is tightly bound (even larger for weathered or aged soils) and is not easily extractable. This fraction is typically present in micropores or chemically bound to soil humic matter and thus is not readily accessible for microbial utilization. The findings presented here for 1,3-DCB are in agreement with those reported for other chemicals in the literature and could have implications to the current remedy, the monitored natural attenuation at the Petro Processors Inc. Superfund site in Louisiana.
Sequence Of Development Of Postural Reactions By Infants With Down Syndrome

SUMMARY The sequential development of postural reactions was examined in 20 infants with Down syndrome aged two to 24 months, and was compared to the sequence for non-handicapped infants. Protective reactions appeared relatively earlier in the sequential pattern for infants with Down syndrome than for non-handicapped infants. The study documents dissimilar sequences of postural reaction development for the two infant groups. The data suggest that both the delay and the dissimilar sequence of postural reactions should be considered when evaluating the motor development and movement quality of infants with Down syndrome. RESUME Le developpement des reactions posturales de nourrissons mongoliens Le developpement sequentiel des reactions posturales a ete etudie chez 20 nourrissons mongoliens âges de deux a 24 mois et compare a la sequence observee chez des nourrissons non handicapes. Des reactions de defense apparaissent relativement plus precocement dans la distribution sequentielle des mongoliens que chez les nourrissons non-handicapes. L'etude souligne des sequences de developpement de reactions posturales dissemblables entre les deux groupes de nourrissons. Les donnees suggerent de considerer a la fois le retard et la dissemblance des sequences de reactions posturales lors de l'evaluation du developpement moteur et de la qualite du mouvement chez les nourrissons mongoliens. ZUSAMMENFASSUNG Entwicklung von Stellreaktionen bei Kindern mit Down-Syndrom Bei 20 Kindern mit Down-Syndrom im Alter zwischen zwei und 24 Monaten wurde der Entwicklungsverlauf von Stellreaktionen untersucht und mit dem bei nicht behinderten Kindern verglichen. Die protektiven Reaktionen erschienen in Sequenzmuster der Kinder mit Down-Syndrom relativ fruher als bei den nicht behinderten Kindern. Die Studie dokumentiert einen ungleichen Entwicklungsverlauf der Stellreaktionen bei beiden Gruppen. Die Daten weisen darauf hin, das sowohl die Verzogerung, als auch der unterschiedliche Entwicklungsverlauf der Stellreaktionen berucksichtigt werden sollten, wenn bei Kindern mit Down-Syndrom die motorische Entwicklung und das Bewegungsmuster beurteilt werden. RESUMEN Desarrollo de las reacciones posturales en ninos con sindrome de Down Se examino el desarrollo secuencial de las reacciones posturales en 20 lactantes con sindrome de Down y de edades entre dos y 24 meses y fue comparado con la secuencia observada en ninos normales. Las reacciones de proteccion aparecieron relativamente mas pronto en los esquemas secuenciales en ninos con el sindrome de Down que en los normales. El estudio muestra unas secuencias de desarrollo postural disimilares en los dos grupos. Los datos sugieren que tanto el retraso como la secuencia disimilar en las reacciones posturales, deben ser tomados en consideracion al evaluar el desarrollo motor y la cualidad de movimiento en ninos con sindrome de Down.
Association between SLC20A1 and sodium-lithium countertransport.

BACKGROUND Sodium-lithium countertransport (SLC) is a premorbidity marker of essential hypertension. Evidence from linkage analysis and kinetic studies in humans have suggested that SLC20A1 variations may affect SLC activity as measured in erythrocytes and leukocytes. SLC20A1 encodes a sodium-dependent phosphate cotransporter, and is widely expressed on the mammalian plasma membrane. In this study, we investigated the relationship between SLC20A1 and SLC activity. METHODS By means of gene expression profiling, we studied the expressions of SLC20A1 in individuals with high SLC activity as compared to those with low SLC activity. In order to investigate the allelic association of SLC20A1 with SLC, we genotyped six tag single-nucleotide polymorphisms (tSNPs) in SLC20A1 in subjects from the Rochester Family Heart Study (RFHS) involving 1,815 individuals from 252 pedigrees of mixed European ancestry. The genetic association of SLC20A1 with SLC was assessed by Sequential Oligogenic Linkage Analysis Routines (SOLAR). RESULTS Expression levels of SLC20A1 were higher in individuals with high SLC activity than in those with low SLC activity. Four SNPs in SLC20A1 were associated with SLC activity after adjusting for age, sex, body mass index, triglycerides, and antihypertensive drug treatment (P ≤ 0.05). The strongest evidence of association was in respect of rs4849091 (P = 0.001), and this association remained significant even after correction for multiple tests. CONCLUSIONS Allelic variations in SLC20A1 were associated with the levels of SLC activity, thereby supporting the hypothesis that SLC20A1 is involved in determining SLC activity.
Disruptive mRNA folding increases translational efficiency of catechol-O-methyltransferase variant

Catechol-O-methyltransferase (COMT) is a major enzyme controlling catecholamine levels that plays a central role in cognition, affective mood and pain perception. There are three common COMT haplotypes in the human population reported to have functional effects, divergent in two synonymous and one nonsynonymous position. We demonstrate that one of the haplotypes, carrying the non-synonymous variation known to code for a less stable protein, exhibits increased protein expression in vitro. This increased protein expression, which would compensate for lower protein stability, is solely produced by a synonymous variation (C(166)T) situated within the haplotype and located in the 5' region of the RNA transcript. Based on mRNA secondary structure predictions, we suggest that structural destabilization near the start codon caused by the T allele could be related to the observed increase in COMT expression. Our folding simulations of the tertiary mRNA structures demonstrate that destabilization by the T allele lowers the folding transition barrier, thus decreasing the probability of occupying its native state. These data suggest a novel structural mechanism whereby functional synonymous variations near the translation initiation codon affect the translation efficiency via entropy-driven changes in mRNA dynamics and present another example of stable compensatory genetic variations in the human population.
Fruit and vegetable food frequencies by fourth and fifth grade students: validity and reliability.

Due to the increased emphasis on fruit and vegetable (F+V) consumption and a desire to use the simplest dietary assessment method appropriate to determine F+V intake, we assessed the reliability and validity of weekly and monthly fruit and vegetable food frequency questionnaires (F+V FFQ) among fourth and fifth grade students by comparing them to food records previously validated through school lunch observations.The multiethnic sample (primarily African-American and Caucasian) included predominantly lower-middle socioeconomic students from 10 classes at one elementary school. F+V FFQ were printed on optical scanning forms and classroom administered on two occasions. Students completed preprinted food record forms at school and received new forms weekly. To allow comparison between the F+V FFQ and food records, a dietitian abstracted information from the records according to a written protocol and transferred it to F+V FFQ forms covering respective time periods. F+V FFQ were converted to estimated daily s...
Comprehensive Management of Trichotillomania in a Young Autistic Girl

The coexistence of trichotillomania and autistic disorder has rarely been reported in psychiatric literature. The current study describes successful treatment of trichotillomania in a young autistic girl, using combined clomipramine and behavioral therapy. Neither behavioral therapy, clomipramine, methylphenidate, buspirone, nor naltrexone was effective in monotherapeutic trials. We postulate a synergistic effect of combined treatment with clomipramine and behavioral therapy, suggesting that both pharmacological and behavioral treatment of hair pulling may be necessary for many patients. This model is consistent with the extant literature and suggests that future clinical trials of clomipramine for trichotillomania, in both developmentally disabled and normal subjects, must evaluate this multimodal approach.
Real‐Time Object‐Oriented Distributed Computing

The sections in this article are 1 Fundamental Issues in RT OO Distributed Computing 2 Design and Execution Tools 3 Basic Design Style: Multilevel Multistep Design