cssi/SciSciGPT-SciSciNet huggingface dataset:
Analysis of the propagation dynamics and Gouy phase of Airy beams using the fast Fresnel transform algorithm

There is great interest in Airy beams because they appear to propagate in a curved path. These beams are usually generated by inserting a cubic phase mask onto the input plane of a Fourier transform system. Here, we utilize a fast Fresnel diffraction algorithm to easily derive both the propagation dynamics and the Gouy phase shift for these beams. The trajectories of these beams can be modified by adding additional linear and quadratic phase terms onto the cubic phase mask. Finally, we have rewritten the equations regarding the propagating Airy beams completely in laboratory coordinates for use by experimentalists. Experimental results are included. We expect that these results will be of great importance in applications of Airy beams.
A Contingent Claims Analysis of Price Level-Adjusted Mortgages

This paper examines the performance of alternative mortgage instruments in an environment of stochastic price fluctuations. The two most widely discussed contracts that deal with inflation are the adjustable-rate mortgage (ARM) and the price level-adjusted mortgage (PLAM). The former compensates for inflation by paying the nominal interest rate, which contains a component reflecting the rate of inflation. Nonetheless, even without explicit nominal amortization, this results in real amortization and hence a tilting effect. In addition, the inflation component of the nominal interest rate is shown to reflect only anticipated and not actual inflation, and so the real value of an ARM fluctuates due to unanticipated inflation. A PLAM suffers from none of these defects. To the extent that one is interested in a mortgage whose properties reflect the underlying real environment, the price level-adjusted mortgage is the ideal instrument.
An Accurate Interferometric Referencing Method for Resonance Tracking in Lab-on-chip Applications

Repeatability of resonance detection for on-chip microring resonators is systematically studied. An efficient interferometric method is presented to improve the accuracy by more than one order of magnitude in an 8 nm bandwidth, without any temperature control.
Transjugular intrahepatic portosystemic shunt (TIPS) for Budd-Chiari syndrome or portal vein thrombosis: review of indications and problems.

Abstract OBJECTIVE: The aim of this study was to evaluate the role of transjugular intrahepatic portosystemic shunt (TIPS) in patients who present with portal vein thrombosis (PVT) or Budd-Chiari Syndrome (BCS). METHODS: Nine patients with recent PVT and four patients with BCS underwent TIPS. The diagnosis was confirmed by color Doppler ultrasound and by angiogram in most patients. Patients were followed clinically and had TIPS checked periodically for patency. The end point was mortality, subsequent surgical shunting or orthotopic liver transplantation (OLT). RESULTS: TIPS was placed in 13 of 15 (87%) patients with BCS or PVT. The mean decrease in pressure gradient was 56%. Median and mean follow-up were 14 months and 16.9 months. Procedure related complications occurred in two of 13 (15%), both in the PVT group. Direct procedural mortality was one of 13 (8%). The majority of patients with PVT (five of eight) underwent OLT. Of the remaining three, one patient subsequently developed a cavernous transformation of portal vein but is stable, one patient is stable, without further variceal bleeding, and one patient died because of multiple organ failure. In patients with BCS, three of four (75%) did well with TIPS, but one patient required immediate surgical shunting after occlusion of the TIPS. Two patients underwent OLT and the fourth patient is stable 2 yr later but has cirrhosis on biopsy. CONCLUSIONS: In patients with BCS, TIPS placement is effective and can be used as a bridge to liver transplantation. TIPS in the noncavernous PVT group should only be recommended when cirrhosis and uncontrollable variceal bleeding are present.
Mutual information for automated unwarping of rat brain autoradiographs.

Abstract An automated multimodal warping based on mutual information metric (MI) as a mapping cost function is demonstrated. Mutual information ( I ) is calculated from a two-dimensional (2D) gray scale histogram of an image pair, and MI (=− I ) provides a matching cost function which can be effective in registration of two- or three-dimensional data sets independent of modality. Most histological image data, though information rich and high resolution, present nonlinear deformations due to the specimen sectioning and need reconstitution into deformation-corrected volumes prior to geometric mapping to an anatomical volume for spatial analyses. Section alignment via automatic 2D registrations employing MI as a global cost function and thin-plate-spline (TPS) warping is applied to deoxy- d -[ 14 C]glucose autoradiographic image slices of a rat brain with video reference images of the uncut block face to reconstitute a cerebral glucose metabolic volume data. Unlike the traditional feature-based TPS warping algorithms, initial control points are defined independently from feature landmarks. Registration quality using automated multimodal image warping is validated by comparing MIs of the image pair registered by automated affine registration and manual warping method. The MI proves to be a robust objective matching cost function effective for automatic multimodality warping for 2D data sets and can be readily applied to volume registrations.
The sandy beach fauna of Egypt

Abstract Intertidal sand beaches along the Mediterranean and Gulf of Suez Egyptian coast were examined in 1985. Mediterranean beaches were characterized by few species, low density, and no Lessepsian migrants. A total of 78 species were collected from sandy beaches in the Gulf of Suez with species richness increasing with decreasing exposure to wave action. The Gulf of Suez fauna was not as diverse as the Gulf of Elat fauna due to lower species equitability and differences in exposure regime. Oil pollution is suggested as a possible explanation for the lowered density of fauna within the Gulf of Suez as compared to the Gulf of Elat.
Promoting Communication between Health Care Providers and Educators of Chronically III Children

Since children with chronic illness need the skills and technical expertise of both health professionals and educators, these groups must learn to work together in a team effort on behalf of the child. In order to maximize communications between the health care providers and educators in special educational programs it is necessary to understand concepts about chronic illness and the ways that health professionals are trained and work within the medical care system and the local community. Suggestions are made about the type of information that educators should obtain from and communicate to health care providers and issues that may enhance effective communication with those in the health system.
Validation of Facilitated Communication

This study reports the results of an attempt to validate a young adult's use of facilitated communication. The individual, Philip, had made allegations of sexual abuse against his father. These allegations were conveyed to two facilitators, one a special education teacher and the other an instructional aide. A comprehensive battery of procedures was developed and then administered to examine the likelihood that Philip could have authored the allegations. Results of the assessment failed to support Philip's possessing the necessary communication skills to have authored the allegations. Charges against his father were subsequently dismissed. While findings of this investigation cannot be generalized beyond Philip, the procedures and accompanying rationale may be useful to other examiners who are engaged in validation activities with facilitated communicators. Implications and proposed guidelines for testing the validation of this method of communication are presented.
The Road to CONSER—Taken by the Health Sciences Library System, University of Pittsburgh

The Health Sciences Library System (HSLS) at the University of Pittsburgh decided to become a member of Cooperative Online Serials (CONSER) in 2003. This came at a time when the library was acquiring an increasing number of electronic journal titles, and recent changes in serials cataloging practices resulted in a need for more bibliographic records conforming to current standards. This article explains the factors involved in the library's decision to join CONSER and then describes the process undertaken by HSLS to become an independent CONSER member, including initial decision-making, record review, and finally reflections on the overall experience.
Newspaper Micropayments and Millennial Generation Acceptance: A Brand Loyalty Perspective

AbstractHow willing are consumers to make micropayments for online news? By exploring that question, this study seeks to not only fill a void in the literature but also address a very practical, yet necessary component to a model the industry appears poised to adopt. Using a brand loyalty scale, this study surveyed undergraduate and graduate students at a large Southeastern U.S. university to find out their general willingness to adopt micropayments. The study indicated that brand loyalty increases user likelihood to adopt micropayments for online newspapers.
Spontaneous activity of clam intestinal muscle

Abstract 1. 1. Longitudinal, non-striated muscle of the cardiac segment of intestine taken from the clams Mercenaria and Spisula show spontaneous constractions, both tonic and phasic, and ganglionic-like electrical discharges associated primarily with the phasic contractions. 2. 2. The evidence—the disruption of spontaneous activity by MS-222, the enhancement by 5-HT, the antagonism between 5-HT and MS-222, the localization of electrical activity to the posterior end of the gut segment where nervous elements are concentrated, the pattern of electical discharges, and the lack of close correspondence between electrical and mechanical records— strongly suggests that the electrical activity recorded originates in nervous elements.
Identifying the presence of a disulfide linkage in peptides by the selective elimination of hydrogen disulfide from collisionally activated alkali and alkaline earth metal complexes

We report a new method for identifying disulfide linkages in peptides using mass spectrometry. This is accomplished by collisional activation of singly charged cationic alkali and alkaline earth metal complexes, which results in the highly selective elimination of hydrogen disulfide (H2S2). Complexes of peptides possessing disulfide bonds with sodium and alkaline earth metal are generated using electrospray ionization (ESI). Isolation followed by collision induced dissociation (CID) of singly charged peptide complexes results in selective elimination of H2S2 to leave newly formed dehydroalanine residues in the peptide. Further activation of the product yields sequence information in the region previously short circuited by the disulfide bond. For example, singly charged magnesium and calcium ion bound complexes of [Lys8]-vasopressin exhibit selective elimination of H2S2 via low-energy CID. Further isolation of the product followed by CID yields major b- and z-type fragments revealing the peptide sequence ...
Increasing carbon dioxide from five percent to ten percent improves rabbit blastocyst development from cultured zygotes.

One-cell rabbit zygotes were cultured at 39°C in basal synthetic medium II (BSM-II) with 5%, 10%, or 15% CO2 and humidified air to determine the effect of CO2 concentration on development in vitro. After 4 days in culture, 37% of the embryos grown in 10% or 15% CO2 had reached the hatching blastocyst stage, but only 10% of the embryos were hatching when cultured under 5% CO2 (P = 0.01). Over all blastocysts, cell numbers were 207, 246, and 205 for the 5%, 10%, and 15% CO2 treatments, respectiveiy. In a second experiment to determine if there was a beneficial effect, particularly at the blastocyst stage, of a higher concentration of CO2, embryos were cultured 4 days in either 5% or 10% CO2 or for 2 days in 5% CO2 followed by 2 days in 10% CO2. The numbers of blastomeres per embryo and embryo diameter were greater (P > 0.05) in embryos cultured continuously in 10% CO2 or in 10% CO2 only during days 3 and 4 of culture than in embryos cultured continuously in 5% CO2. In a third experiment, one-cell rabbit zygotes were cultured with 5% or 10% CO2 in a defined, protein-free medium consisting of 1:1 RPMI 1640 and Dulbecco's modified Eagle's medium. The proportion of embryos hatching and cell counts were significantly greater (P > 0.01) when cultured in the presence of 10% CO2. These data indicate that a 10% CO2 atmosphere exerts a beneficial effect on the development of zygotes into expanding and hatching rabbit blastocysts in vitro. © 1992 Wiley-Liss, Inc.
Concepts of the Display of Medical Images

Display is the step of the imaging chain in which the image is put into a form viewable by an observer. The objectives of display can be qualitative or quantitative, and each requires different display approaches. For each objective, producing a high-quality result requires facing issues in both the space and intensity dimensions. In the spatial dimension the major choices are of sampling and interpolation. In the intensity dimension the major choices are of sampling, display scales, assignment by the display device of display scale values to display-driving intensities, and contrast enhancement. Concepts and approaches, but not hardware, for each of these choices will be presented.
An update on human interleukin-1: from molecular biology to clinical relevance

Interleukin-1 (IL-1) represents a family of polypeptides with a wide range of biological activities. At least two dissimilar gene products have been cloned; there are probably more. The human IL-1 family plays an important role in the pathogenesis of many diseases and functions as a key mediator of the host response to various infectious, inflammatory, and immunologic challenges. Recombinant mouse (pI 5) and recombinant human (pI 7) IL-1's are being used to confirm the multiple biological properties of IL-1's but considerable investigation is required before the specific activities (biological units per milligram of protein) are established for each human IL-1 form. Some IL-1 biological activities such as the induction of hepatic acute-phase protein synthesis have been demonstrated in invertebrates predating the evolution of lymphocytes. IL-1 is highly inflammatory and increases the concentration of metabolites of arachidonic acid, most notably prostaglandin E2, in brain, muscle, chondrocytes, and synovial fibroblasts. The synthesis of leukotrienes also is involved in the mechanism of its action on certain tissues. The cloning and expression of human IL-1 genes will expand our understanding of IL-1 in various diseases through improved detection systems and the use of cDNA probes; the development of IL-1 antagonists, as well as the use of IL-1 as an immunomodulator, is presently being considered.
INFLUENCE OF INSULIN AND ENVIRONMENTAL FACTORS ON GLUCOSE UPTAKE IN EPIDIDYMAL FAT TISSUE.

Abstract An 8- to 10-fold stimulation by insulin of glucose uptake by epididymal fat tissue was obtained in serial incubations of this tissue in a simplified medium composed of tris (hydroxymethyl) aminomethane chloride, CO 2 , and glucose. The replacement of chloride ions in the incubation medium by acetate or other anions resulted in an increase in the glucose uptake by epididymal fat tissue in the absence of insulin to a level approaching the rate obtained in the medium in the presence of insulin. This effect is not readily reversed by addition of chloride ions to the medium after the incubation period. Chloride ions, therefore, appear necessary for the maintenance of insulin responsiveness of the system. During incubation in tris chloride, there is a rapid appearance of significant quantities of sodium and potassium into the incubation medium. This ionic redistribution did not influence significantly the normal basal glucose uptake or its stimulation by insulin. The presence of the hormone also did not influence the rate of appearance of these ions in the incubation medium. It is suggested that the sodium ions appearing in the incubation medium are derived primarily from the intercellular space. The stimulation of glucose uptake by amorphous (zinc-low) insulin in a zinc-free tris chloride medium was similar to that observed in a zinc-containing system. The uptake of zinc ions into the tissues was not markedly influenced by insulin. As the pH of the incubation medium is increased from 6 to 7, glucose uptake by insulin-treated tissue increased while that of tissue without insulin remained constant. In the region from pH 7 to 8, the uptake by insulin-stimulated tissue remained maximal while the uptake by tissue without insulin increased to this level, thus abolishing the insulin effect. The effects of pH on the basal glucose uptake were not reversed by readjusting the pH after the incubation period. There was no marked difference in the rate of utilization of α- and β-glucose by epididymal fat tissue in the presence or absence of insulin under conditions where two- or threefold differences in rate would have been expected if one of the forms was specifically utilized by the system. Lineweaver-Burk plots of glucose uptake as a function of glucose concentration in the presence and absence of insulin indicate the action of insulin is primarily in increasing the uptake of glucose by epididymal fat tissue at low glucose concentrations. The apparent K m of the system in the absence of insulin is about 60 m M , and in the presence of this hormone is 7 m M . The maximal glucose uptake, about 2 μmoles/100 mg. tissue per hour, is obtained at high levels of glucose and is not significantly affected by insulin. These data are consistent with a role of insulin on a rate-limiting step in the process (probably glucose transport). It is suggested that various treatments of the tissue which are reported here to increase the glucose uptake in the absence of insulin probably affect the permeability of the cells.
Clinical utility of magnetic resonance imaging in pediatric neurosurgical patients

The clinical utility of magnetic resonance imaging in pediatric neurosurgical patients was reviewed in a series of 126 scans. MRI was determined to be superior or equivalent to other imaging techniques in the evaluation of intracranial hypertension, developmental abnormalities, or acute conditions involving the spinal cord. In 74% of the scans performed because of these clinical problems, adequate data were obtained for both specific anatomic diagnosis and surgical planning. The scan proved equivalent to CT in the imaging of structural abnormalities associated with seizure disorders or degenerative conditions. In acute head injuries and generalized infections of the central nervous system, MRI offered no advantage in diagnostic specificity, and had significant logistic limitations.
Mid-infrared laser reflectance of moist soils.

The effect of varying moisture content on the mid-infrared (9–11-μm) laser backscatter reflectance of different soils was investigated experimentally. Total reflectance was separated into a diffuse and a coherent component. Consistent with observations in the visible and near-infrared spectral regimes, the diffuse mid-infrared reflectance values decrease with increasing gravimetric moisture content. At low moisture contents, this phenomenon is attributed to increased forward scattering, while total internal reflection at the water–air interface results in lower reflectance values at higher moisture contents. The coherent component, however, increases initially for low moisture content as a result of the reduction in surface roughness on moistening, decreases subsequently, and then tends to increase again as the moisture content nears the field capacity of the soil. An empirical model based on the above physical mechanisms is developed for the diffuse component and tested by using the measured data. It is conjectured that the laser reflectance is sensitive to moisture in the surface layer (≃ 0.25-mm depth) and thus may have the potential to monitor near-surface soil moisture.
Investigation of red oil decomposition by simulated Hanford tank wastes

Abstract Samples of ‘red oil’ have been placed in contact with simulated Hanford tank wastes, and Differential Scanning Calorimetry used to compare energetic content both before and after exposure to these waste simulants. Of the 85 samples studied, 44 samples had their energy content reduced by 90% or more following contact with waste simulant, while 77 of the 85 samples showed at least a 50% fall in energy content. All 85 samples showed at least some reduction in energetic content. The duration of contact between red oil and waste simulant was generally a few hours or days, and the overwhelming majority of the data suggest that contact times of several years, as would be typical in Hanford waste tanks, would further reduce the energy content of red oil to negligible quantities.
Terahertz Detection with Tunneling Quantum Dot Intersubband Photodetector

The characteristics of a tunnel quantum dot intersublevel photodetector, designed for the absorption of terahertz radiation, are described. The absorption region consists of self-organized In0.6Al0.4As/GaAs quantum dots with tailored electronic properties. Devices exhibit spectral response from 20 to 75 m 4 THz with peak at 50 m. The peak responsivity and specific detectivity of the device are 0.45 A/W and 108 cm Hz1/2 /W, respectively, at 4.6 K for an applied bias of 1 V. Response to terahertz radiation is observed up to 150 K. © 2006 American Institute of Physics. DOI: 10.1063/1.2233808
Pregnancy and Vasculitis

Until recently, the prognosis associated with many forms of systemic vasculitis was quite grim. Advances in this field have allowed us to begin to focus on issues related to quality of life such as fertility, conception, and pregnancy among women with vasculitis. Because the systemic vasculitides are rare diagnoses, many important questions remain unanswered. Overall, it seems that women who have inactive vasculitis may not be subject to unusual complications during pregnancy, but our understanding of the interaction between pregnancy and specific forms of vasculitis continues to evolve.
Digital control of a coupled fluidized-bed thermal processing system for tar sands

A digital control system, consisting of an HP-1000 host computer, an HP-2250 interface, and several actuators and sensors, was used to control a laboratory unit for the thermal processing of tar sand. The unit included two coupled fluidized beds for pyrolyzing the bitumen content of the tar sand and combusting the resulting coke left behind on the sand. The condensed pyrolyzate is suitable for upgrading to a synthetic crude oil. The control system for solids retention times in both fluidized beds included four pressure gauges, two dp cells, two pressure transmitters and two solids-flow control valves. A digital proportional-integral-derivative (PID) algorithm plus valve linearization to eliminate hysteresis of control valves were found to be the best control method. The preferred control constants, (Kc = 80, τi = 40, τd = 0 for the pyrolysis reactor, and Kc = 50, τi = 5, τd = 0 for the combustion reactor), were found experimentally. The temperature in the pyrolysis reactor (450–550°C) could be controlled by the amount of energy transferred into the combustion reactor from the surroundings. An SCR power controller was used to regulate power into a heating wire wrapped around the combustion reactor wall. The best PID algorithm controller constants, (Kc = 1000, τi = 10, τd = 0) for controlling the thermal cracking of bitumen in the pyrolysis reactor were found experimentally. From the controlled variable responses, it was concluded that the digital control system used here was much superior to the analog controllers used previously.
O2(b1ϵg+ → X 3ϵg−) emission following HO2 photodissociation by KrF laser photons

Abstract HO2 produced by three-body reaction H + O2 + M → HO2 + M was photoexcited using a KrF laser (248 nm). The O2(b 1ϵg+ → X3ϵg−) emission band was observed following photodissociation of HO2. The primary product of HO2 photodissociation is likely to be O(1D), which then transfers its energy to O2 to form O2(b 1ϵg+).
Calculated properties of fully hydrogenated single layers of BN, BC2N, and graphene: Graphane and its BN-containing analogues

Carbon is an attractive material for hydrogen adsorption due to its light weight, variety of structures, and ability to both physisorb and chemisorb hydrogen. Recently, fully hydrogenated graphene layers (``graphane'') have been predicted to exist [J. O. Sofo et al., Phys. Rev. B 75, 15340 (2007)], and experimentally observed [D. C. Elias et al., Science 323, 610 (2009)]. In this work, we examine analogs of graphane, in particular ${\text{BNH}}_{2}$ and ${\text{BC}}_{2}{\text{NH}}_{4}$. Unlike graphene, these materials have a band gap without hydrogenation. Our results indicate that the hydrogenation product of BN is metastable: the fully hydrogenated compound ${\text{BNH}}_{2}$ is higher in energy than hexagonal BN sheets plus ${\text{H}}_{2}$ molecules, in sharp contrast with graphane. We find that ${\text{BC}}_{2}{\text{NH}}_{4}$ is energetically very close to hexagonal ${\text{BC}}_{2}\text{N}+2{\text{H}}_{2}$ molecules. Furthermore, our examination of the relative binding strengths of rows of symmetry related hydrogen atoms on ${\text{BC}}_{2}{\text{NH}}_{4}$ shows that this compound is marginally higher in energy than ${\text{BC}}_{2}{\text{NH}}_{2}$ plus an ${\text{H}}_{2}$ molecule, with the hydrogen atoms in ${\text{BC}}_{2}{\text{NH}}_{2}$ absorbed on the carbon sites. These remaining hydrogen atoms are not as strongly bound as in graphane, indicating that the average hydrogen chemisorption energy is controllable by changing the carbon content in the B-C-N layer.
Idealism held hostage: Jimmy Carter's rhetoric on the crisis in Iran

This essay argues that Carter's perceived passivity during the Iranian hostage crisis largely derived from the idealism of his rhetoric. Carter's public talk was grounded in an idealist's terminology which was distinctive because of its emphasis upon genus—specifically, his definition of who Americans were and what they were like—and the application of that genus to crisis problem‐solving. According to Carter, U.S. policies not only had to achieve pragmatic results, but also had to be consistent with his definition of the nation's moral character. Through such arguments, the President constrained his ability to take effective action and failed to provide citizens with evidence that his policies would work. Carter's discourse demonstrates the role that both idealism and pragmatism play in successful presidential crisis rhetoric.
Carbon-13 nuclear magnetic resonance studies of cerebroside derivatives and their properties in lecithin bilayers (1).

Abstract The 13C NMR chemical shifts and spin-lattice relaxation times of D-galactosylsphingosine derivatives in CDCl3-CD3OD and in egg-yolk lecithin vesicles in D2O, and of N-acetylpsychosine micelles, are reported. Results with sonicated, unilamellar vesicles containing cerebroside and EYLa show that (1) cerebrosides decrease the fluidity of the lecithin bilayer membrane and have the greatest effect on the glycerol backbone and choline methyl carbons. (2) N-acetylpsychosine experiences a greater freedom of motion in the galactose region than does cerebroside and does not reduce the fluidity of the lecithin as much as cerebroside. (3) Ac-Psy/EYL vesicles formed are permeable to Yb3+ but cerebroside/lecithin vesicles are not. (4) The choline groups on the inner bilayer surface are less mobile than those on the outer surface according to preliminary T1 measurements of the Yb3+-separated resonances. (5) Yb3+-induced chemical shifts of choline methyl and choline C H 2 OP peaks in mixed cerebroside-lecithin vesicle systems indicate a small preference for cerebroside in the outside monolayer. The data show that these molecules have significant effects on bilayer conformational mobilities, particularly near the surface, and thus demonstrate one mechanism for modulation of cell surface properties by glycosphingolipids.
Human Tissue Distribution of Cyclodiene Pesticides—Hawaii 1964-1973

Data have been presented covering symptoms of acute exposure to cyclodiene pesticides in adults and infants in Hawaii. Varying concentrations of heptachlor epoxide, dieldrin, DDT, DDE, and DDD were found in human autopsy material, with the highest levels of heptachlor epoxide in bone marrow and liver and those of dieldrin in kidney and gonad. Maximum concentration of dieldrin in human milk was 0.25 ppm on an extracted lipid basis; in fetal tissues, 1.46 ppm; and in maternal tissues, 2.04 ppm. There was correlation between dieldrin concentration in household dust and human blood serum. The general baseline levels of cyclodiene pesticides were lower in Hawaii than the rest of the United States.
Second-harmonic generation spectroscopic study of silicon nanocrystals embedded in SiO2

Cross-polarized 2-beam second-harmonic generation, with enhanced signal from both the nano-interface and nanocrystal bulk, supplemented with spectroscopic ellipsometry and Raman spectroscopy, has been applied spectroscopically to study the embedded Si NCs of different sizes.
Problems with the differential receiver operating characteristic (DROC) method

Most papers in these proceedings present ideas that work. This is the story of an idea that did not work as intended. The differential receiver operating characteristic (DROC) method was proposed about 8 years ago. It was intended to measure the difference in performance between two imaging modalities. It was expected that the DROC method could outperform the ROC method in statistical power. This expectation has not been borne out and the author no longer recommends the DROC method. The purpose of this paper is to present a critical look at this method, why the author initially believed it should work, the assumptions involved and the fallacies. The author believes there is value to this frank account as it has yielded, at least for the author, new insights into ROC analysis. The author concludes with a few personal reflections on his experience with this project and advice on how to deal with negative results.
Cortisol Determination and the Dexamethasone Suppression Test: A Review

• The possibility that unreliability of plasma cortisol level determinations might interfere with the use of the dexamethasone suppression test (DST) in clinical practice was evaluated by examining published data on the reliability of plasma cortisol determinations as well as a comparison of two radioimmunoassay (RIA) methods with a competitive protein binding assay (CPBA). Significant discrepancies between various methods of plasma cortisol level determinations have been reported in most, but not all, studies. The most widely used method, RIA kits, may not produce levels comparable with those produced by the CPBA, used in a recent effort to standardize the DST for use in psychiatry. The use of the DST by physicians should be preceded by an assessment of the validity of the cortisol level determinations in the critical range for the DST by the laboratory they use.
On the small N Performance of bootstrap and bayes extended and unextended set compound rules for classification between N( -1,1)and N(1,1)†

We study a situation in which N independent classifications between N(- 1; 1) and N(1,1) are to be faced simultaneously. This problem was the featured example in Robbins′ (1951) introduction of the compound decision problem and has been used many times since to illustrate various aspects of the developing theory of compound and empirical Bayes decisions. We here study the moderate N risk behavior of recently developed so-called “extended” bootstrap and Bayes procedures for the prob!em. The behavicr of :hese rules is compared to that of the bootstrap and Bayes rules originally suggested by Robbins.
Uniqueness for the harmonic map flow from surfaces to general targets

LetM be a two-dimensional compact Riemannian manifold with smooth (possibly empty) boundary,N an arbitrary compact manifold. Ifu andv are weak solutions of the harmonic map flow inH 1(Mx[0,T]; N) whose energy is non-increasing in time and having the same initial datau 0∈H1(M, N) (and same boundary values if ∂M≠O) thenu=v. Combined with a result of M. Struwe, this shows any suchu is smooth in the complement of a finite subset ofM×(0,T)c.
Masking of auditory brainstem responses in young and aged gerbils

Auditory brainstem responses (ABR) were recorded in the presence of low-pass (1 kHz cutoff) or high-pass (8 kHz cutoff) filtered noise in young (4-8 month) and aged (36 month) gerbils. For low-pass maskers, aged gerbils had higher masked thresholds at 2 and 4 kHz than young subjects. This was true for all aged subjects, including those with quiet thresholds similar to those of young controls. For high-pass masking, the majority of aged subjects had higher masked thresholds at 2 and 4 kHz than young controls; however, aged subjects with relatively normal quiet thresholds had masked thresholds similar to those of young subjects. A modified power-law (MPL) model was used to predict masked thresholds for aged subjects. Thresholds measured in the presence of low-pass noise were higher than predicted in many of the aged subjects, particularly those with near-normal quiet thresholds. In contrast, thresholds measured in the presence of the high-pass masker were similar to the predicted thresholds. These results suggest that: (a) excess masking occurred in aged subjects for low-pass, but not high-pass, maskers; (b) the excess masking occurred independently of quiet thresholds; and (c) excess upward spread of masking was related to the spectrum of the masker and not the 2 and 4 kHz regions of the auditory periphery.
Clinical benefit of power-injectable port systems: A prospective observational study

Abstract Objective To prospectively evaluate the clinical benefit of a central venous port system, which is approved for contrast media injection during contrast enhanced computed tomography. Materials and methods At a university teaching hospital, 98 patients (59 female, 39 male; median age 61.7 years; range 23–83) had a power-injectable central venous port catheter system implanted. All implantations were performed under ultrasonographic and fluoroscopic guidance by interventional radiologists. Procedure related immediate (up to 24 h after implantation), early ( Results An overall complication rate of 0.69 for 1,000 catheter days in 78 evaluated ports was recorded (12 ports affected, 15.4%). During the observational period, 40 of 104 contrast enhanced computed tomography scans were performed utilizing the port for contrast media administration (38.5%). 30 catheter tip retractions of more than 3 cm were observed in 82 patients (36.6%). Overall, tip dislocations were statistically more frequent in the female subgroup. Conclusion The complication rate found in this study is comparable to those, which have been published for standard port systems. The utilization of the device for contrast media injection during contrast enhanced computed tomography scans should be increased. Finally, the port capsule has to be carefully positioned and fixed to prevent migration.
Failure in Composite Angle Structures Part I: Initial Failure

Failure in composite angle structures was studied experimentally and analyzed using Hill and an augmental Hill-Tsai failure criteria. In general, there were two possible failure modes, i.e., initial transverse matrix cracking due to bending stress, and final delamina tion due to through-the-thickness normal stress in the curved region. Depending on the layup, some laminates could fail in delamination without experiencing transverse matrix cracking. The 3-D Hill failure criterion was found excellent in predicting failure of this type of composite structure.
Renal dysplasia associated with in utero exposure to gentamicin and corticosteroids.

We report on a patient with renal cystic dysplasia, whose mother was given gentamicin and corticosteroids early in pregnancy. We speculate that these drugs may be implicated in abnormal nephrogenesis in humans. This speculation is based on gentamicin-induced small kidneys (oligonephronia) in the rat. Renal cystic disease has been demonstrated following glucocorticoid administration early in gestation. We realize that there is no proof for a causal relationship between gentamicin and/or glucocorticoids in the pathogenesis of this patient's renal disease. However, it is possible that renal cystic dysplasia in humans is not solely the result of a genetic defect. © 1995 Wiley-Liss, Inc.
Analysis by the reductive-cleavage method of linkage positions in a polysaccharide containing 4-linked D-glucopyranosyluronic residues.

Abstract The fate of 4-linked d -glucopyranosyluronic residues under reductive-cleavage conditions was investigated by using the Klebsiella aerogenes type 54 strain A3 capsular polysaccharide. Treatment of the fully methylated polysaccharide with triethylsilane and trimethylsilyl trifluoromethanesulfonate in dichloromethane, followed by in situ acetylation, yielded 1,5-anhydro-2,3,4,6-tetra- O -methyl- d -glucitol, 3,4-di- O -acetyl-1,5-anhydro-2,6-di- O -methyl- d -glucitol, and 3- O -acetyl-1,5- anhydro-2,4-di- O -methyl- l -fucitol, as expected, but the expected product of reductive cleavage of the 4-linked d -glucopyranosyluronic residue, namely, methyl 3- O - acetyl-2,6-anhydro-4,5-di- O -methyl- l -gulonate, was not observed. Instead, methyl 2- O -acetyl-3,6-anhydro-4,5-di- O -methyl- l -gulonate ( 6 ) was identified as the sole product of reductive cleavage of the 4-linked d -glucopyranosyluronic residue. That compound 6 arose as a result of rearrangement during reductive cleavage rather than by reductive cleavage of a 5-linked d -glucofuranosyluronic residue, was established by reductive cleavage of the fully methylated polysaccharide following reduction of its ester groups with either lithium aluminum hydride or lithium aluminum deuteride. The products of the latter reductive cleavage were the same as before, except for the absence of 6 and the presence of 4,6-di- O -acetyl-1,5- anhydro-2,3-di- O -methyl- d -glucitol, or its 6,6-dideuterio isomer. Although the reductive-cleavage technique is suitable for the direct analysis of polysaccharides containing 4-linked- d -glucopyranosyluronic residues, it does not establish whether the uronic residue is a 4-linked pyranoside or a 5-linked furanoside. The expected product is, however, derived from the 4-linked d -glucopyranosyluronic residue after sequential methylation, reduction of its ester group and reductive cleavage.
Lack of Evidence for the Direct Activation of Endothelial Cells by Adult Female and Microfilarial Excretory-Secretory Products

Lymphangiectasia (dilation of the lymphatic vessel (LV)) is pathognomonic for lymphatic filariasis. In both infected humans and animal models of infection, lymphangiectasia is not restricted to the site of the worm nest, but is found along the infected vessel. These observations argue that soluble products secreted by the worm could be mediating this effect by activating the lymphatic endothelial cells (LEC) lining the vessel. We tested the ability of filarial Excretory-Secretory products to activate LECs, but were unable to detect a direct effect of the Excretory-Secretory products on the activation of LEC as assessed by a variety of approaches including cellular proliferation, cell surface molecule expression and cytokine and growth factor production (although other mediators used as positive controls did induce these effects). Collectively, these results do not support the hypothesis that Excretory-Secretory products directly activate LECs.
Engineering the spatial selectivity of surfaces at the nanoscale using particle lithography combined with vapor deposition of organosilanes.

Particle lithography is a practical approach to generate millions of organosilane nanostructures on various surfaces, without the need for vacuum environments or expensive instrumentation. This report describes a stepwise chemistry route to prepare organosilane nanostructures and then apply the patterns as a spatially selective foundation to attach gold nanoparticles. Sites with thiol terminal groups were sufficiently small to localize the attachment of clusters of 2−5 nanoparticles. Basic steps such as centrifuging, drying, heating, and rinsing were used to generate arrays of regular nanopatterns. Close-packed films of monodisperse latex spheres can be used as an evaporative mask to spatially direct the placement of nanoscopic amounts of water on surfaces. Vapor phase organosilanes deposit selectively at areas of the surface containing water residues to generate nanostructures with regular thickness, geometry, and periodicity as revealed in atomic force microscopy images. The area of contact underneath t...
The effect in humans of exercise on relationship between simultaneously measured 133Xe and 24Na clearances

In four normal men the clearance rates of 133Xe and 24Na from a forearm muscle depot were followed at rest and during and after light to maximal forearm exercise. At rest the clearance rates were similar, but with maximal exercise the clearance of 24Na increased only 10 times compared to 30 times for the clearance of 133Xe, indicating a diffusion limited clearance of 24Na at high blood flows. The data were used to calculate a permeability-surface area product for the transport of sodium from tissue to blood, a measure of the maximal diffusion capacity for sodium. This value increased successively with rising work load and about sixfold from rest to maximal exercise. The increase with exercise is considered to reflect an increase in capillary surface area and probably also variations in a nonuniform capillary circulation.
Congenital pulmonary airway malformation (congenital cystic adenomatoid malformation) with multiple extrapulmonary anomalies: Autopsy report of a fetus at 19 weeks of gestation

Congenital pulmonary airway malformation, or congenital cystic adenomatoid malformation, is postulated to be a disorder of pulmonary airway morphogenesis and encompasses 5 different types with distinct levels or stages of tracheobronchial development. We present a unique case of type 2 congenital pulmonary airway malformation with a previously undocumented combination of multiple extrapulmonary anomalies, featuring ipsilateral multicystic renal dysgenesis, contralateral renal agenesis, and ovarian germ cell hypoplasia, diagnosed in a 19-week gestational age fetus by autopsy. Epithelial cells comprising the pulmonary lesions were positive for thyroid transcription factor-1, surfactant protein-B, and cytokeratin-7 but negative for cytokeratin-20 immunostainings, with the pattern seen in normal terminal bronchioles. Chromosomal analysis showed a normal female karyotype, despite a high estimated risk for Down syndrome suggested by the low maternal serum alpha-fetoprotein level.
Real-time optical monitoring of epitaxial growth: pulsed chemical beam epitaxy of GaP and InP homoepitaxy and heteroepitaxy on Si

We present a study of the real-time monitoring of the homoepitaxial growth of GaP, InP, and the growth of InP/GaP and GaP/Si(001) heterostructures, combining single wavelength p-polarized reflectance (PRS), reflectance-difference spectroscopy (RDS), and laser light scattering (LLS) during pulsed chemical beam epitaxy with tertiarybutylphosphine, triethylgallium, and trimethylindium sources. The growth rate and the bulk optical properties are revealed by PRS with submonolayer resolution over 1000A of film growth. The surface topography is monitored by LLS providing additional information on the evolution of the surface roughness as well as the nucleation/growth mechanism. The optical surface anisotropy, which is related to surface reconstruction and/or surface morphology, is monitored by RDS and compared with the results of PRS and LLS. The results are discussed with respect to the deposition kinetics, in particular as a function of the V:III flux ratio. The pulsed supply of chemical precursors causes a periodic alteration of the surface composition, which is observed as correlated periodic changes in the RD and PR signals, confirming the high sensitivity of both methods to surface chemistry.
Phenotypic heterogeneity of Gross virus-induced thymic lymphomas in the rat: cellular origins and migratory properties.

Abstract Neoplastic thymocytes from rat thymic lymphoma-leukemias induced by the rat-adapted Gross leukemia virus (RAGV) were analyzed for a variety of differentiation markers. The neoplasms from individual rats all expressed the antigenic phenotype MP + , W3/13 + , Thy-1 + , RT-1 + , RT-7 + , W3/25 − . However, approximately two-thirds of the neoplasms were positive for the OX 8 antigen, and one-third were negative. The OX 8 − neoplasms only involved the thymus, whereas approximately 40% of the OX 8 + neoplasms involved the spleen as well as the thymus. Virtually all OX 8 + and OX 8 − neoplastic cells contained terminal deoxynucleotidyl transferase (TdT), and both OX 8 + and OX 8− lymphomas expressed the lactate dehydrogenase (LDH)-5′ isozyme and the primary, but not the secondary, ADA isozyme. This enzymatic phenotype is characteristic of thymocyte precursors, but not thymocytes. Our results therefore indicate that RAGV-induced lymphomas arise from transformed prethymic TdT + cells which contain the LDH-5′ and the primary ADA isozymes. These preleukemic cells presumably migrate to the thymus where they express the RT-7 pan-T-cell antigen and, in some instances, the OX 8 antigen during the development of overt leukemia. The OX 8 + neoplasms, being more differentiated than their OX 8 − counterparts, then migrate to peripheral lymphoid tissues.
A depressive endophenotype of mild cognitive impairment and Alzheimer's disease.

Background Alzheimer’s disease (AD) is a devastating public health problem that affects over 5.4 million Americans. Depression increases the risk of Mild Cognitive Impairment (MCI) and AD. By understanding the influence of depression on cognition, the potential exists to identify subgroups of depressed elders at greater risk for cognitive decline and AD. The current study sought to: 1) clinically identify a sub group of geriatric patients who suffer from depression related cognitive impairment; 2) cross validate this depressive endophenotype of MCI/AD in an independent cohort.
Calibrating ESCA and ellipsometry measurements of perfluoropolyether lubricant thickness

X-ray reflectivity (XRR) has been used as an absolute measurement of the thickness of perfluoropolyether (PFPE) lubricant layers on silicon substrates to determine the validity of thickness measurements by electron spectroscopy for chemical analysis (ESCA) and ellipsometry. Excellent agreement is found between these three methods, provided that a 25 /spl Aring/ escape depth for the PFPE film is used in ESCA and the bulk refractive index of the PFPE is used in ellipsometry. It is also essential to properly account for adventitiously adsorbed hydrocarbons.
Contact and crack problems for an elastic wedge

The contact and the crack problems for an elastic wedge of arbitrary angle are considered. The problem is reduced to a singular integral equation which, in the general case, may have a generalized Cauchy kernel. The singularities under the stamp as well as at the wedge apex were studied, and the relevant stress intensity factors are defined. The problem was solved for various wedge geometries and loading conditions. The results may be applicable to certain foundation problems and to crack problems in symmetrically loaded wedges in which cracks initiate from the apex.
Paramagnetic Pd2+ ions in trigonal sites of CsMgCl3 crystals

Abstract Crystals of CsMgCl 3 grown from melts containing small amounts of PdCl 2 exhibit a noticeable coloration indicating the incorporation of Pd 2+ ions into the lattice. The EPR spectra of the crystals contain the features characteristic of a S=1 ion in a trigonal site with spin Hamiltonian parameters of: g ∥ = 2.18, g ‖ = 2.16, and |D| = 0.25 cm −1 . This paper describes the spectra and discusses the unusual paramagnetic ground state for Pd 2+ .