cssi/SciSciGPT-SciSciNet huggingface dataset:
Learning eye movement patterns for characterization of perceptual expertise

Human perceptual expertise has significant influence on medical image inspection. However, little is known regarding whether experts differ in their cognitive processing or what effective visual strategies they employ for examining medical images. To remedy this, we conduct an eye tracking experiment and collect both eye movement and verbal description data from three groups of subjects with different medical training levels. Each subject examines and describes 42 photographic dermatological images. We then develop a hierarchical probabilistic framework to extract the common and unique eye movement patterns exhibited among multiple subjects' fixation and saccadic eye movements within each expertise-specific group. Furthermore, experts' annotations of thought units on the transcribed verbal descriptions are time-aligned with these eye movement patterns to identify their semantic meanings. In this work, we are able to uncover the manner in which these subjects alternated their viewing strategies over the course of inspection, and additionally extract their perceptual expertise so that it can be used for advanced medical image understanding.
Angiogenin as a molecular target for the treatment of prostate cancer

Angiogenin (ANG), a 14 kDa angiogenic ribonuclease, is upregulated in human prostate cancers, especially in hormone refractory diseases, and is the highest upregulated gene in Akt-driven prostate intraepithelial neoplasia (PIN) in mice. ANG has been shown to undergo nuclear translocation in both prostate cancer cells and cancer-associated endothelial cells where it binds to the promoter region of ribosomal DNA (rDNA) and stimulates ribosomal RNA (rRNA) transcription. ANG thus plays an essential role in prostate cancer progression by stimulating both cancer cell proliferation and tumor angiogenesis. A variety of ANG antagonists, including its antisense oligonucleotide, siRNA, soluble binding proteins, monoclonal antibody, enzymatic inhibitors, and nuclear translocation blockers, have all been shown to inhibit prostate cancer in various animal models. Accumulating evidence indicates that ANG is a molecular target for prostate cancer drug development.
Distributed Computing Column 57 Distributed Algorithms as Combinatorial Structures

For many distributed computing problems there exists a characterizing combinatorial structure. In other words, the existence of an algorithm for solving the problem on any graph G in time T (G) implies the existence of the structure in G with some parameter related to T (G), and vice versa. Such relations go back to classic examples, such as synchronizers and sparse spanners, and continue to emerge in recent studies of gossip algorithms and multicast algorithms in different communication settings. In this article, we give an overview of both old and recent results that illustrate these connections. We discuss how finding distributed algorithms as well as proving lower bounds can be reduced to studying combinatorial graph structures. “An algorithm must be seen to be believed” – Donald Knuth, The Art of Computer Programming
The Bone Morphogenetic Protein 1/Tolloid-like Metalloproteinases

A decade ago, bone morphogenetic protein 1 (BMP1) was shown to provide the activity necessary for proteolytic removal of the C-propeptides of procollagens I-III: precursors of the major fibrillar collagens. Subsequent studies have shown BMP1 to be the prototype of a small group of extracellular metalloproteinases that play manifold roles in regulating formation of the extracellular matrix (ECM). Soon after initial cloning of BMP1, genetic studies showed the related Drosophila proteinase Tolloid (TLD) to be necessary for the formation of the dorsal-ventral axis in early embryogenesis. It is now clear that the BMP1/TLD-like proteinases, conserved in species ranging from Drosophila to humans, act in dorsal-ventral patterning via activation of transforming growth factor beta (TGFbeta)-like proteins BMP2, BMP4 (vertebrates) and decapentaplegic (arthropods). More recently, it has become apparent that the BMP1/TLD-like proteinases are activators of a broader subset of the TGFbeta superfamily of proteins, with implications that these proteinases may be key in orchestrating the formation of ECM with growth factor activation and BMP signaling in morphogenetic processes.
Mercury's Atmosphere from Mariner 10: Preliminary Results

Analysis of data obtained by the ultraviolet experiment on Mariner 10 indicates that Mercury is surrounded by a thin atmosphere consisting in part of helium. The partial pressure of helium at the terminator is about 5 trillionths of a millibar. The total surface pressure of the atmosphere is less than about 2 billionths of a millibar. Upper limits are set for the abundance of various gases, including hydrogen, oxygen, carbon, argon, neon, and xenon. The wavelength dependence of Mercury's surface albedo is similar to that of the moon over a broad range of wavelengths from 500 to 1600 A. Strong signals were recorded by the airglow instrument as Mariner 10 passed through the cavity behind Mercury. They are as yet unexplained but may provide information on the properties of the local plasma.
Reversible thermo-responsive sieving matrix for oligonucleotide separation

A reversible thermo-responsive gel system, consisting of Pluronic copolymer mixture of F87 and F127, has been used to successfully carry out the separation of oligonucleotides, for the first time, by microchip-based capillary electrophoresis. Pluronic triblock copolymers F87 (E(61)P(40)E(61)) and F127 (E(99)P(69)E(99)), with E, P, and subscript denoting oxyethylene, oxypropylene, and segment length respectively, have a unique temperature dependent viscosity-adjustable property and a dynamic coating ability in aqueous solution, including 1 x TBE buffer. The mixture solution has a reversible thermo-responsive property and its sol-gel transition temperature can be adjusted ranging from about 17 degrees C to 38 degrees C by varying the relative weight ratio of F87 and F127 at an optimized concentration of approximately 30% (w/v) for oligonucleotide separations. Oligonucleotide sizing markers ranging from 8 to 32 base could be successfully separated in a 1.5 cm long separation channel by the mixture solution in its gel-like state. A 30% (w/v) with a F87/F127 weight ratio of 1 ratio 2 which has a "sol-gel" transition point of about 26 degrees C shows the best sieving ability. The sieving ability of the mixture solution was further confirmed in an Agilent Bioanalyzer 2100 system. Fast separation of oligonucleotides has been achieved within 40 s with one base resolution.
Use of Questionnaire Surveys in Forming Fishery Management Policy

Abstract The desirability of incorporating fishermen preferences into management decision making was identified. A questionnaire survey technique based on a random sample of residents was developed to obtain unbiased assessment of angler preference. The survey technique was tested in the Owasco Lake (New York) watershed. A random sample of 1,092 Owasco Lake Basin residents was used to evaluate their preference for fishing and fishery management policies. The questionnaire was pre-tested for question effectiveness and clarity. A total of 794 completed forms were returned (73%). Effect of non-response was estimated through a phone survey of 60 nonrespondents. Twenty-nine percent of Owasco Lake Basin households contained Owasco Lake fishermen. Of those who fished at Owasco, 21% preferred lake trout, 17% preferred rainbow trout, 15% preferred walleye, and 47% other species. The most frequently cited reasons for fishing were: “for relaxation,” “to get outdoors,” and “for fun.” The results represent an assessme...
Spatial and temporal patterns of transparency and light attenuation in the Salton Sea, California, 1997-1999

Swan, B.K., K.M. Reifel, M.A. Tiffany, J.M. Watts and S.H. Hurlbert. 2007. Spatial and temporal patterns of transparency and light attenuation in the Salton Sea, California, 1997-1999. Lake Reserv. Manage. 23:653-662. Transparency, as measured by Secchi disk depth (SD), and light attenuation (Kd(PAR)) were measured in the Salton Sea in 1997-1999. Linear regression models were used to evaluate the relative importance of phytoplankton and non-phytoplankton substances in determining SD and Kd(PAR). Paired measurements of SD and Kd(PAR) made in 1999 were used to track relative changes in the importance of light absorption and scattering processes. Phytoplankton biomass was a poor predictor of both SD and Kd(PAR) at mid-lake stations, and this is most likely due to high concentrations of non-phytoplankton substances such as inorganic particulate matter in the Salton Sea. During strong windstorms in the warmer part of the year, the upper water column mixes with hydrogen sulfide-laden bottom waters, causing large crashes in plankton populations. This previously reported phenomenon also strongly affects the light regime through the production of gypsum crystals, which scatter large portions of penetrating light. Since a large amount of variation in both SD and Kd(PAR) is not explained by phytoplankton biomass, any use of this relationship to forecast future changes in water clarity through nutrient reductions must be done with caution.
Medical therapy of Prinzmetal's variant angina.

Medical therapy for Prinzmetal's variant angina has been treatment of the acute attack with sublingual nitroglycerin. Prophylactic therapy has been more difficult, utilizing long-acting vasodilators that are limited because of their short half-life and side effects when therapeutic doses are used. Alpha-adrenergic blockade has been effective in some patients but is frequently associated with intolerable side effects or apparent development of tolerance to the drug. Preliminary experience from a randomized double-blind trial of diltiazem, a new calcium antagonist, has demonstrated a 90 percent reduction in pain episodes, with many patients becoming pain-free on the 240-mg daily dose. These data and the lack of adverse side effects demonstrate a dramatically effective therapy for patients with coronary artery spasm. Summary Nitroglycerin remains highly effective and the drug of choice for the acute treatment of angina due to coronary artery spasm. Long-acting nitrates and α-blockers are only partially useful for prophylaxis of angina attacks because of the high frequency of adverse side effects at therapeutic levels of these drugs. Based on multiple uncontrolled trials, calcium antagonists appear to be effective for the long-term prophylaxis. Preliminary experience with diltiazem in a randomized double-blind study indicates dramatic therapeutic efficacy with no adverse side effects in a small group of patients with classic Prinzmetal's angina.
Child Protective Services Investigations and the Transition to Foster Care: Children's Views:

During a pilot qualitative study about children's views of Child Protective Services (CPS) investigations, the problem for study broadened to include children's views of the transition to foster care generally. Findings indicated that (1) the CPS investigation was not an emotionally charged topic for these respondents, and (2) respondents were ambivalent about foster care, liking many aspects while also missing birth parents. Respondents (most in care for the first time) were in care for nonemergency reasons, and for brief periods (1 to 5 months). These circumstances may have influenced the findings. In some cases, videotape supplemented audiotape of research interviews. Videotape proved useful, but not necessary to establish findings. Implications for research, practice, and policy are provided.
Computer system for quantitative evaluation of an electrotactile vocoder for artificial hearing

A computer-controlled experimental electrotactile vocoder system is designed to evaluate quantitatively the transmission of speech information and to test various design options for tactual vocoders. The system is composed of a digital speech synthesizer, a digital vocoder, a computer-driven electrotactile display, and an adaptive controller for psychophysical experimentation. Samples of continua representing speech contrast types occurring in natural languages are synthesized by systematically manipulating selected subphonemic features. The synthesized speech stimuli are processed using a programmable vocoder and presented to the skin with an electrotactile display belt worn on the abdomen. Transmission of significant speech parameters is quantitatively evaluated using adaptive psychophysical techniques and labeling tests. The system is used to assess the potential of speech transmission through the skin and to evaluate different vocoder configurations and processing techniques for tactual vocoders to be used as artificial hearing devices by the deaf.
a-Plane GaN light emitting diodes on self-assembled Ni nano-islands

Nitride-based light emitting diodes (LEDs) have received great attention with emission wavelength from ultraviolet to green. However, conventional c-plane GaN LEDs suffer from polarization-related electric fields, which result in poor carrier recombination efficiency and red-shift in the emission wavelength. In order to reduce the undesirable polarization effects, non-polar plane GaN LEDs have been proposed and reported. But the non-polar films also suffer from poor crystalline quality and rough surface morphology, especially for hetero-epitaxy. Several research groups have reported high performance non-polar GaN-based LEDs grown on bulk GaN substrates [1]. However, high price, small size, and non-uniformity in the substrates also make them difficult for mass production. On the other hand, nano-patterned a-plane GaN on sapphire substrate has been proposed as a solution. It is thought of as a method to achieve low cost, large area, and high uniformity a-GaN on sapphire. In this paper, self-assembled Ni nano-islands [2] are applied to form a-plane GaN nanorod template. We also grew blue and green [3] nano-patterned a-plane GaN LEDs on those nanorod templates.
A study of the control of Nd3+ energy levels in fluorozirconate glasses

Abstract Nd3+-doped ZBLAN single-mode fibers have been fabricated and optical amplification around 1340 nm has been obtained. However no gain has been observed in the 1300 nm region, which is used in most of the current telecommunication systems. This problem is because of the existence of the excited state absorption (ESA). In order to improve gain characteristics around 1300 nm, ESA and fluorescence wavelengths must be controlled by changing the ligand field around Nd3+ ions. Some Nd3+-doped fluorozirconate-based glasses, in which other alkali elements were substituted for Nd were prepared and absorption, fluorescence and lifetime characteristics of the Nd3+ ions in the glasses were examined. As a result, it was found that the ESA wavelength was shifted by the alkali elements systematically.
Imine Hydrogenation by Tribenzylphosphine Rhodium and Iridium Complexes

The iridium complexes [Ir(PBz3)2(COD)]PF6 and [Ir(py)(PBz3)(COD)]PF6 are effective catalyst precursors for the homogeneous hydrogenation of N-(β-naphthylmethylene)aniline (NβNA) to naphthalene-2-ylmethylphenylamine (PBz3 = tribenzylphosphine; COD = 1,5-cyclooctadiene; py = pyridine). For comparative purposes, other iridium and rhodium catalysts modified with either PBz3 or PPh3 have been tested as catalysts for NβNA hydrogenation. A kinetic study of this reaction catalyzed by [Ir(PBz3)2(COD)]PF6, [Ir(py)(PBz3)(COD)]PF6, and [Rh(PPh3)2(COD)]PF6, together with in situ NMR experiments, has led us to propose catalytic cycles for the three precursors.
Juvenile and family mental health law in sociohistorical context

The mental health care of children and youth cannot be considered in historical context without looking more broadly at the treatment of delinquent, neglected, abused, dependent, and mentally and emotionally handicapped youngsters. Recognizing that there has always been overlap among these categories, policies toward such youngsters were and are intimately connected to the nature of the welfare system, the prevailing views of the rights of parents vis-a-vis the state, and society’s willingness to commit public resources to the care and treatment of “problem” children and youth. We began with an undifferentiated view of the problems of youth and the means useful in dealing with those problems. Increasing specialization of services has reflected not only scientific advances in our understanding of the problems of youth but also changes in social conditions. The spirit of a particular time has brought certain problems to our attention and supported action in relation to those socially defined problems. With these themes in mind, this Article provides a brief overview of the historical development of juvenile and family mental health law and policy in the United States. While the emphasis is on the development of mental health law and policy in the American sociohistorical context, the roots of such law and policy clearly predate even the establishment of the first American colonies.
Comparison of direct percutaneous endoscopic jejunostomy and PEG with jejunal extension

Abstract Background: Jejunostomy tubes can be placed endoscopically by means of percutaneous gastrostomy with jejunal extension (PEG-J) or by direct percutaneous jejunostomy. These 2 techniques were retrospectively compared in patients requiring long-term jejunal feeding. Method: An endoscopy database was used to identify all patients who underwent endoscopic jejunal feeding tube placement from January 1996 to May 2001. Patients with a history of upper GI surgery were excluded. There were 56 patients with a direct percutaneous jejunostomy and 49 with a percutaneous gastrostomy with jejunal extension. Patients in the direct percutaneous jejunostomy group received a 20F direct jejunostomy tube; a 20F PEG tube with a 9F jejunal extension was used in the percutaneous gastrostomy with jejunal extension group. Medical records for the period of 6 months after establishment of jejunal access were reviewed. Complications and need for further endoscopic intervention within this time frame were recorded. The duration of feeding tube patency (number of days from established jejunal access to first endoscopic reintervention) was compared for both groups. Results: Feeding tube patency was significantly longer in patients who had a direct percutaneous jejunostomy compared with those with a percutaneous gastrostomy with jejunal extension. Within the 6-month period, 5 patients with a direct percutaneous jejunostomy required endoscopic reintervention for tube dysfunction compared with 19 patients who had a percutaneous gastrostomy with jejunal extension ( p Conclusions: For patients who require long-term jejunal feeding, a direct percutaneous jejunostomy with a 20F tube provides more stable jejunal access compared with a percutaneous gastrostomy with jejunal extension with a 9F extension and has a lower associated rate of endoscopic reintervention. (Gastrointest Endosc 2002;56:890-4.)
The effect of wiping on skin resurfacing in a pig model using a high energy pulsed CO2 laser system.

Background. The impact of wiping in laser skin resurfacing has not been systematically studied. Methods. We examined the effects of wiping during single- and multiple-pass high energy pulsed CO2 laser skin resurfacing in a farm pig. Consequences of wiping were evaluated with regard to depth of residual thermal damage, tissue necrosis, and fibroplasia. Also, the impact of wiping on gross wound healing was observed. Wounds were followed for 21 days and biopsies were obtained on postoperative days 0, 1, and 21. Results. Immediate postoperative biopsies of single-pass wounds showed equivalent residual thermal damage regardless of wiping; in contrast, biopsies from multiple-pass sites without wiping showed more extensive and variable residual thermal damage than wiped sites. On postoperative day one, single pass sites without wiping were grossly less erythematous than wiped sites, and biopsies showed less extensive necrosis and inflammation. In contrast, multiple pass sites without wiping were grossly more erythematous than corresponding wiped sites, and biopsies revealed significantly increased and variable necrosis. After 21 days, multiple pass sites without wiping were grossly more erythematous and showed a thicker band of fibroplasia microscopy. Conclusions. For single pass wounds, not wiping decreased the level of wounding. In contrast, not wiping in multiple pass wounds significantly increased the depth and variability of residual thermal damage and necrosis, resulting in prolonged healing.
Oxygen Cycles and Metabolic Autoregulation

Rhythmical three to eight per minute cycles in oxygen availability are characteristic of recordings from chronically implanted open tip polarographic electrodes. These were demonstrated to be progressively decreased in amplitude as mean arterial blood pressure was raised from 75 mm Hg to 160 mm Hg, at which level they were abolished. Amplitude of these :ycles also decreased as BP was reduced below 75 mm Hg and they again disappeared at an iverage of 60 mm Hg. Oscillation frequency appeared to be a function of rate of metabolism, oeing reduced by anesthesia, hypothermia, and ischemia. An hypothesis is proposed which relates these oscillations to the feedback delay between metabolic generation of CO2 and the appropriate adjustment in tension of the pH sensitive muscle of the precapillary arteriole which in turn determines rate of local CO2 clearance. The changes in amplitude of the oxygen cycles may indicate alteration in pH reactivity of precapillary smooth muscle as a function of BP.
Signature Pedagogies for Social Foundations: Negotiating Social Foundations Teaching Practices in the Field of Education

The conflicts arising between the pedagogical preferences of the fields of instructional design and technology (IDT) and social foundations of education are substantial. This conflict is primarily one of pedagogical values separating the Social Foundations with its emphasis on critical and creative thinking and the presumption of value and theory neutrality inherent in IDT. This is a serious issue because, increasingly, educators use IDT models to translate Social Foundations courses with social justice and equity outcomes into online formats. Much is lost. This article offers a discussion of the theoretical grounding of IDT (task-analysis) versus social foundations in regards to implications for the instructional social organization of online social foundations classrooms. This article uses the notion of signature pedagogy to describe sociocultural literacies as a basic tenet in social foundations of education. By doing so, it is demonstrated how these important theoretical positions are currently playin...
Chloroform Pyrolysis: Experiment and Detailed Reaction Model

Abstract Chloroform was used as a model chlorocarbon system with high Cl/H ratio to investigate the thermal decomposition processes of chlorocarbons in pyrolytic reaction environments. The thermal decomposition of 1.0% chloroform in argon bath gas was studied to determine important chlorocarbon reaction pathways in pyrolysis. The reactions were studied in tubular flow reactors at a total pressure of 1 atm with residence times of 0.3-2.0 sec in the temperature range 535-800°C. A detailed kinetic reaction mechanism to describe the important features of products and reagent loss was developed. The mechanism is based on thermochemical principles and accurately describes the overall reaction process. We determine that the primary decomposition reaction pathway for chloroform is: CHCl3 → HCl +: CCl2 in the above temperature regime by combined experiment and modeling studies. High pressure limit rate constants obtained in this work for initially important decomposition of chloroform were determined as: A(1/sec.)...
Probabilistic Decline Curve Analysis of Barnett, Fayetteville, Haynesville, and Woodford Gas Shales

Abstract This paper presents a probabilistic decline curve workflow to model shale gas production from the Barnett, Fayetteville, Haynesville, and Woodford shales. Ranges of model input parameters for four gas shales are provided to guide the preparation of uniform and triangle probability distributions. The input parameter ranges represent realistic distributions of model parameters for specific gas shales.
Peer Reporting to Control Employee Theft

Organizations use many methods to control chronic losses due to theft. Since many studies indicate employee deviance is a significant problem, companies implement a series of countermeasures, including peer-reporting hotlines and incentives. This paper explores the dynamics of peer reporting, as well as current peer-reporting processes. Although study participants used peer reporting, the components of their programs varied widely.
Aldosterone breakthrough during aliskiren, valsartan, and combination (aliskiren + valsartan) therapy

Aldosterone levels increase in 30%-40% of patients on angiotensin-converting enzyme inhibitors and/or angiotensin receptor blockers over the long term. This "aldosterone breakthrough" may carry important clinical consequences given aldosterone's nonepithelial, pro-fibrotic actions. The renin inhibitor, aliskiren, by suppressing the renin-angiotensin-aldosterone system (RAAS) proximally, may limit breakthrough compared to conventional RAAS blockade. This open-label study (NCT01129557) randomized subjects to aliskiren 300 mg daily (A), valsartan 320 mg daily (V), or aliskiren 150 mg + valsartan 160 mg daily (A+V) for 9 months. Eligible subjects had proteinuria >300 mg/day, estimated glomerular filtration rate (eGFR) >45 mL/min/1.73 m(2), and systolic blood pressure (BP) >130 or diastolic BP >80 mm Hg. Serum and 24-hour urine aldosterone (indexed to 24-hour urine Na) were checked before initiation of therapy and at 3, 6, and 9 months. Aldosterone breakthrough was defined as a sustained increase from baseline aldosterone by study end. The study was intended to enroll 120 subjects but was terminated early by the sponsor. We present here the results of 33 subjects who completed the protocol, of which 12 were randomized to A, 11 were randomized to V, and 10 were randomized to A+V. Mean baseline eGFR was 75.5 (±23.3) mL/min/1.73 m(2); baseline proteinuria was 3104 (±2943) mg/day; and baseline BP was 134.7 (±10.5)/84.8 (±8.4) mm Hg. Three (27%) subjects on V, three (25%) subjects on A, and three (30%) subjects on A+V had aldosterone breakthrough. Mean proteinuria reduction was 31% from baseline in all subjects: 30% in subjects with breakthrough vs. 32% in subjects without breakthrough. Mean BP reduction was 11.0/8.8 mm Hg in all subjects: 8.4/6.1 mm Hg in subjects with breakthrough vs. 12.0/9.8 mm Hg in subjects without breakthrough. Aliskiren, alone or in combination with valsartan, did not reduce the incidence of aldosterone breakthrough in subjects with hypertension and proteinuria compared with conventional RAAS blockade.
New taxa and combinations in neotropical Juncus (Juncaceae)

Juncus arequipensis andJ. breviculmis are described as new species, andJ. ramboi subsp.colombianus as a new subspecies.Juncus arcticus Willd. var.mexicanus (Willd.), var.montanus (Engelm.), and var.andicola (Hook.) are proposed as new combinations.
Size and Surface Effects on the Phonon Properties of Small Particles

Measurements on thin films and surfaces have generated a need for a technique whereby one can calculate the phonon properties of small particles containing only a few hundred atoms. We have used moleculardynamic techniques to calculate the frequency distribution and various moments for five different particle configurations. Results are compared with the bulk solid. A model extending the Lennard-Jones and Devonshire cell model to surface environments is described. It is shown that this model replicates features of the more exact calculation. The frequency spectrum and various correlation functions are decomposed into contributions from the bulk, surface, and edge of a particle. The differences can be explained in terms of the local environment.
Multi-objective global optimization for hydrologic models

The development of automated (computer-based) calibration methods has focused mainly on the selection of a single-objective measure of the distance between the model-simulated output and the data and the selection of an automatic optimization algorithm to search for the parameter values which minimize that distance. However, practical experience with model calibration suggests that no single-objective function is adequate to measure the ways in which the model fails to match the important characteristics of the observed data. Given that some of the latest hydrologic models simulate several of the watershed output fluxes (e.g. water, energy, chemical constituents, etc.), there is a need for effective and efficient multi-objective calibration procedures capable of exploiting all of the useful information about the physical system contained in the measurement data time series. The MOCOM-UA algorithm, an effective and efficient methodology for solving the multiple-objective global optimization problem, is presented in this paper. The method is an extension of the successful SCE-UA single-objective global optimization algorithm. The features and capabilities of MOCOM-UA are illustrated by means of a simple hydrologic model calibration study.
Longitudinal acoustic mode in polymers. V. Nature of perturbing forces in n-paraffins and polymers

Binary mixtures of n-paraffins have been examined by Raman spectroscopy in order to elucidate the nature of the perturbations on the chains. For a short-chain species diluted in a longer-chain species, the longitudinal acoustic mode frequency of the former decreases from its value in the pure state to that corresponding to a chain with free ends. This observation, as well as others, confirms our previous suggestions that longitudinal perturbing forces are responsible for increasing this frequency over its unperturbed value. These results also provide new insights into the structures present in solid solutions of n-paraffins. They reemphasize the necessity of incorporating the effects of such perturbations in applications of the longitudinal acoustic mode to morphological studies of polymers.
A PRIMER OF NEGATIVE TEST DIMENSIONS AND DEGREES OF EMPTINESS FOR LATENT SETS

Applied blindly, the formula for the dimension of the intersection can give negative results. Extending Minkowski's definition of the dimension by ∊-neighborhoods to ∊-pseudo-neighborhoods, that is, replacing (A ∩ B)∊ with A∊ ∩ B∊, we introduce the notion of negative dimensions through several examples of random fractal constructions.
Chromosomal abnormalities in chronic lymphocytic leukemia.

Abstract Peripheral blood lymphocytes from five chronic lymphocytic leukemia (CLL) patients were cultured with PHA for 3–6 days. Chromosomal analysis with G-banding showed 25% of the diploid metaphases were pseudodiploid as a result of either a chromosomal deletion or a translocation. Abnormal clones with 18p− were seen in two patients, and two other patients had 18p− metaphases, but with other inconsistent abnormal chromosomes. None of the patients had trisomy 12, which has been thought by some to carry a poor prognosis. Although no conclusion can be reached regarding the significance of the chromosomal abnormalities in CLL, the type of chromosomal abnormalities in these patients suggests that they are the result of chromosomal breakage and abnormal repair.
The seeding of methane oxidation

Abstract Mixtures of light alkanes and oxygen can be converted into useful products by catalytic partial oxidation in excess fuel at moderate temperature. The relative importance of homogeneous chemistry in the reactions is still a subject of active debate, and, in this paper, the gas-phase partial oxidation of methane was simulated using detailed chemical reaction mechanisms. The sensitivity of homogeneous chemistry to the addition of trace amounts of radical and molecular species was analyzed to evaluate both the possibility of heterogeneous assistance to gas-phase reactions and the effectiveness of different species which might be added as promoters of particular product selectivities. Seeding of reaction mixtures with 2% of radicals reduced the homogeneous ignition delay time by only 50% at 1400 K. The delay was fairly insensitive to particular radical seeds because the radical pool adjusts rapidly. Seeding does not alter the product selectivity to CO and H 2 except at low conversion.
Laser microprobe study of sulfur isotope variation in a sea-floor hydrothermal spire, Axial Seamount, Juan de Fuca Ridge, eastern Pacific

Abstract The Axial Seamount site is located on the Juan de Fuca Ridge near the intersection of the Cobb-Eikenberg-Brown BEar seamount chain and the axial rift of the ridge. Several large (to 12 m) silica+sulfide+sulfate hydrothermal spires reflect high-temperature (to 300°C) hydrothermal activity. Laser microprobe analyses along traverses of five temporally distinct fluid conduits within an inactive high-temperature spire reveal significant temporal variation inδ 34 S, both within individual conduits and between conduits. The maximum intra-conduitδ 34 S variation (on wurtzite) is 5‰ and the maximum inter-conduit variation (on sphalerite) is 7.4‰ Inter-conduitδ 34 S variation occurs primarily due to variable amounts of seawater mixing with hydrothermal fluids within the spire; generallyδ 34 S mineral decreases through time due to lesser amounts of seawater that invade more mature, heavily mineralized spires. Intra-conduitδ 34 S variation has not been documented at this scale (5‰ within 1 mm), and the potential mechanisms responsible for this variation include: (1) within-spire seawater-hydrothermal fluid mixing, which also produces the inter-conduit variations, or (2) more deep-seated convection and redox processes in the sea-floor subsurface that alter theδ 34 S fluid . Mixing of hydrothermal fluid with seawater cannot produce a range ofδ 34 S mineral -values of this magnitude (5‰), and deeper subsurface processes are required. Such deep-seated processes may involve the opening of new fluid conduits in the subsurface, exposing fresh basalt which will increase the reduction potential of the rock system. This in turn will promote increased reduction of seawater sulfate in the hydrothermal fluid and attendant increases ofδ 34 S fluid . The fluids will ulti precipitate 34 S-enriched sulfide phases, although this excursion inδ 34 S-values is ephemeral and will last only until the fluid has exhausted the reducing potential of the new conduit. At this point, sulfate reduction will be sharply reduced andδ 34 S-values will correspondingly decrease. This process may explain the major (to +5‰) isotope excursions that occur within individual conduits on a very small (
Cancer risk assessment in a hereditary cancer prevention clinic and its first year's experience

BACKGROUND. Hereditary cancer accounts for 5-10% of the estimated 1.38 million cancer cases in 1997 and requires an approach to cancer prevention that is distinct from its sporadic counterpart based on its differing natural history. The laboratory advances in the molecular biology of hereditary cancer have recently resulted in the development of specialized hereditary cancer clinics with both broad and syndrome specific hereditary cancer assessment capabilities. A key question is how well these clinics can accomplish this new mission. METHODS. A total of 58 people underwent hereditary cancer risk assessment in the Creighton University Hereditary Cancer Prevention Clinic from September of 1995 to September of 1996. Assessment included construction of a detailed pedigree and a cancer-directed medical history and physical examination. Cancer education, genetic counseling, the option of DNA testing when appropriate, and cancer prevention recommendations based on cancer risk were provided. RESULTS. The 58 patients were comprised of 51 females (88%) and 7 males (12%) predominantly from the Omaha, Nebraska geographic region. Forty patients (69%) were cancer unaffected whereas 18 (31%) were cancer affected; patient age ranged from 6 to 70 years with a mean age of 40 years. Thirty (52%) of the patient families were diagnosed with a hereditary cancer syndrome, 24 (41%) were diagnosed with familial cancer risk, and 4 (7%) were diagnosed with sporadic cancer risk. Of the 30 families with hereditary cancer syndromes, only 4 (13%) individuals have so far undergone DNA testing due to a variety of emotional, financial, insurance, and technical barriers. CONCLUSIONS. The authors have successfully implemented a clinically applicable hereditary cancer prevention program based on their expertise in hereditary cancer risk assessment that offers DNA testing through a commercial laboratory to patients diagnosed with hereditary cancer syndromes. However, a number of barriers to DNA evaluations exist that will require discussion among the medical, legislative, insurance, and lay communities in addition to further research in hereditary cancer risk assessment, genetic counseling, and cancer prevention strategies.
Structure of child care education: Issues and implications for educators and practitioners

This paper focuses on the structure of child care education while integrating some major issues with respect to the role of the child care worker, the content of training and education, and research and evaluation. This overview is followed by discussions of pre-service and in-service training and education. The final section proposes that the development of educational programs and professionalization may be dependent to a large extent on the identification of the skills and competencies for child care workers which result in effective programs for children.
Spectrum of hemodynamic changes in cardiac tamponade

To investigate the pathophysiology of cardiac tamponade, the hemodynamics of 77 consecutive patients with >150 ml of pericardial effusion were studied. Patients were classified into 3 groups based on the equilibration of intrapericardial with right atrial and pulmonary arterial wedge pressures (mm Hg): group I (n = 16), intrapericardial pressure was less than right atrial and pulmonary arterial wedge pressures; group II (n = 13), intrapericardial pressure was equilibrated with right atrial but not pulmonary arterial wedge pressures; group III (n = 48), intrapericardial pressure was equilibrated with right atrial and pulmonary arterial wedge pressures. Pericardiocentesis produced the following changes: group I—significant (p < 0.03) decreases in intrapericardial pressure (7 ± 2 mm Hg), right atrial pressure (3 ± 2 mm Hg), pulmonary arterial wedge pressure (2 ± 2 mm Hg), and the inspiratory decrease in arterial systolic pressure (3 ± 4 mm Hg) but no significant change in cardiac output; group II—significant (p < 0.02) decreases in intrapericardial pressure (11 ± 5 mm Hg), right atrial pressure (6 ± 4 mm Hg), pulmonary arterial wedge pressure (4 ± 5 mm Hg), and inspiratory decrease in arterial systolic pressure (8 ± 7 mm Hg), and increase in cardiac output (1.1 ± 1.2 liters/min); group III—significant (p < 0.001) decreases in intrapericardial pressure (16 ± 7 mm Hg), right atrial pressure (9 ± 4 mm Hg), pulmonary arterial wedge pressure (8 ± 5 mm Hg), inspiratory decrease in arterial systolic pressure (17 ± 11 mm Hg), and increase in cardiac output (2.8 ± 1.5 liters/min). The changes after pericardiocentesis in all parameters were significantly (p < 0.05) greater in group III than in groups i or II except for the change in right atrial pressure, which was not significantly different in groups II versus III. The changes after pericardiocentesis indicate pericardial effusion caused the greatest abnormalities in group III but also caused significant abnormalities of pressure and flow in group II and of pressure alone in group I. Because hemodynamic alterations were noted in all groups, increasing in severity from groups I to III, it is concluded that cardiac tamponade is not an “all-or-none” phenomenon, and the severity of hemodynamic derangement rather than its presence or absence should be assessed in patients with pericardial effusion.
What did Russians Mean When They Called Themselves "Slaves of the Tsar"?

The Germans criticize the fact that here people of all ranks call themselves the “sovereign's slaves.” But they do not consider that among diem people call themselves “vassals,” and this word is not Latin, but German, and means “orphan,” and so all Germans once called themselves in their language. Similarly, the tide “knecht” was once dignified, and even today Scotsmen call their dignified cavaliers “knechts,” diat is, “slaves.“ —Iurii Krizhanich, Politika, 1663-66 The analysis of ritual plays an important role in efforts to reconstruct medieval mentalities. Often mute and always cryptic, medieval cultures rarely provide historians widi the rich programmatic texts that facilitate the study of political ideas. In response to this relative dearth of treatises and manifestoes, scholars have turned to various forms of symbolic behavior for clues concerning the character of the medieval mind. Students of Muscovy are certainly no exception. Recognizing that Old Russia was particularly “silent” (as George Florovsky put it), historians of late have turned their attention to the iconography of Russian life in an attempt to divine the nature of Muscovite ideology, and particularly political ideology.
Pattern recognition in molecular dynamics

Abstract An algorithm for the recognition of the formation of bound molecular states in the computer simulation of a dilute gas is presented. Applications to various related problems in physics and chemistry are pointed out. Data structure and decision processes are described. Performance of the FORTRAN program on the algorithm in cooperation with the molecular dynamics program is described and the results are presented.
Graph sparsification approaches to scalable integrated circuit modeling and simulations

Unlike traditional fast SPICE simulation techniques that rely on a variety of approximation approaches to trade off simulation accuracy for greater speed, SPICE-accurate integrated circuit (IC) simulations can truthfully predict circuit electrical behaviors, and therefore become indispensable for verification of large IC designs. Post-layout SPICE-accurate simulation should be able to encapsulate multi-million or even multi-billion devices that are coupled through complex parasitics and become an essential procedure for verification of nowadays nano-scale IC designs. Although many efficient numerical methods have been developed and adopted in the state-of-the-art SPICE-accurate circuit simulators for solving large sparse matrices involved in IC simulations, existing simulators may not be capable of handling extremely large-scale post-layout ICs in that the computation and memory cost can increase exponentially with the increase of circuit sizes and parasitics components. This paper introduces our recent effort in developing “truly scalable” SPICE-accurate nonlinear circuit simulation methods that can scale comfortably with extremely large-scale post-layout IC designs without sacrificing accuracy.
BLOCH OSCILLATIONS AND OTHER DYNAMICAL PHENOMENA OF ELECTRONS IN SEMICONDUCTOR SUPERLATTICES

We solve the time-dependent Schroedinger equation based on the complete Hamiltonian for independent electrons in ideal GaAs/Al{sub {ital x}}Ga{sub 1{minus}{ital x}}As superlattices, described by the conventional one-dimensional flat-band picture, subject to a uniform electric field {ital F}. Our approach consists of using high-accuracy numerical methods, thereby enabling us to avoid truncating the Hamiltonian or adopting other uncontrolled approximations. In suitable circumstances the electrons exhibit long-lived, time-periodic Bloch oscillations, in the form of either sinusoidal center-of-mass oscillations or a coherent breathing mode. Depending on the miniband structure of the superlattice, the value of {ital F}, and the form of the initial wave function, other dynamical phenomena can coexist with or even totally mask the Bloch oscillations. These are unbounded acceleration of a portion of the electron wave packet antiparallel to the electric field and intrawell oscillations. We provide the conditions under which each of these three basic dynamical elements occurs. We summarize the major results of our systematic investigation of the dependence of the electron dynamics on the entire parameter space of periodic potentials, field strengths, and initial wave functions.
Scalar wave solution for the scattering of a partially coherent beam from a statistically rough metallic surface

The scattering of a spatially partially coherent wave from a one-dimensional statistically rough metallic surface is investigated. Assuming a Gaussian Schell-model form for the incident field autocorrelation function, a closed-form expression for the scattered field autocorrelation function is derived using the physical optics approximation (Kirchhoff approximation). Two forms of the solution are derived—one applicable to very rough surfaces and the other applicable to moderately rough surfaces. It is shown that for very rough surfaces, the solution, under certain circumstances, remains Gaussian Schell model as has been previously reported. As such, closed-form expressions for the angular coherence radius and angular scattering radius are derived. These expressions are, in general, complicated functions of both the source (size and coherence properties) and surface parameters (surface height standard deviation and correlation length). It is demonstrated that for many scenarios of interest, the angular coherence radius can be safely approximated as a function of just the source parameters and the angular scattering radius can be simplified to a function of just the surface parameters. For the moderately rough surface solution, the scattered field autocorrelation function is, in general, not Gaussian Schell model and it is therefore not possible to derive analytical forms for the angular coherence radius or angular scattering radius. Nonetheless, the form of the autocorrelation function is physically intuitive and is discussed in this work. To verify the presented theoretical analysis, wave optics simulation results are presented and compared to the predictions of the analytical models. This analysis is concluded with a discussion of future work.
Identifying the default mode network structure using dynamic causal modeling on resting-state functional magnetic resonance imaging.

Abstract The default mode network is part of the brain structure that shows higher neural activity and energy consumption when one is at rest. The key regions in the default mode network are highly interconnected as conveyed by both the white matter fiber tracing and the synchrony of resting-state functional magnetic resonance imaging signals. However, the causal information flow within the default mode network is still poorly understood. The current study used the dynamic causal modeling on a resting-state fMRI data set to identify the network structure underlying the default mode network. The endogenous brain fluctuations were explicitly modeled by Fourier series at the low frequency band of 0.01–0.08 Hz, and those Fourier series were set as driving inputs of the DCM models. Model comparison procedures favored a model wherein the MPFC sends information to the PCC and the bilateral inferior parietal lobule sends information to both the PCC and MPFC. Further analyses provide evidence that the endogenous connectivity might be higher in the right hemisphere than in the left hemisphere. These data provided insight into the functions of each node in the DMN, and also validate the usage of DCM on resting-state fMRI data.
Evaluation of serologic Tests for Pneumocystis carinii antibody and antigenemia in patients with acquired immunodeficiency syndrome

Sera from 68 patients with acquired immunodeficiency syndrome and 135 controls were used to evaluate the indirect immunofluorescence and enzyme-linked immunosorbent assays for detection of antibodies to Pneumocystis carinii and a counterimmunoelectrophoresis assay for detection of circulating Pneumocystis antigen. None of these assays was helpful in the diagnosis of P. carinii pneumonia. An improved assay for antigenemia is needed to differentiate between clinical and subclinical infection.