cssi/SciSciGPT-SciSciNet huggingface dataset:
Cleaning methods, gas adsorption and corrosion characteristics of a (100) chromium single crystal using low energy electron diffraction☆

Methods for obtaining an atomically clean surface of a Cr(100) single crystal are described. Adsorption of the diatomic gases, nitrogen, carbon monoxide and oxygen, respectively, appear to result in a crystal structure with the face centered interstitial positions of the originally b.c.c. chromium structure occupied by the gas molecules or atoms in question. The adsorbed gases can be removed from the surface by heating the crystal to about 50 °C after nitrogen adsorption, 100 °C after CO adsorption and 300 °C after oxygen adsorption. Initial sticking probabilities are 0.03 for N2, 0.2 for CO and 0.3 for 02. The non-corrosive character of chromium is attributed to a strongly bound amorphous layer of chromic oxide, formed by heating atomieally clean chromium to 800 °C in oxygen at exposures of 10−6 Torr-min, or above. This amorphous layer can be removed by 1000 V argon ion bombardment.
Determination of carbonate-bound barium in foraminifera and corals by isotope dilution plasma-mass spectrometry

Abstract The trace-metal content of biogenic carbonates reflects seawater concentrations only if one can selectively determine the portion of metal bound into the Ca lattice site. We have developed a procedure to purify benthic foraminifera shells of extraneous sedimentary, organic and diagenetic Ba. The purification procedure involves treatment similar to those developed for the determination of Cd in foraminifera shells but with the addition of an alkaline-DTPA step to dissolve away sedimentary barite associated with the shells. Paired-sample studies and partial dissolution of benthic foraminifera confirm the effectiveness of this procedure. Ba/Ca is determined on the purified shells by measurement of Ba by isotope dilution inductively coupled plasma-mass spectrometry (ID-ICP-MS) and Ca by flame atomic absorption. Long-term precision of the foraminifera Ba/Ca determinations is between ±2% and ±3%. We have also developed a rapid procedure for ID-ICP-MS determination of Ba in aragonite coral samples with routine precisions of
Casein kinase I phosphorylates and destabilizes the β-catenin degradation complex

Wnt signaling plays a key role in cell proliferation and development. Recently, casein kinase I (CKI) and protein phosphatase 2A (PP2A) have emerged as positive and negative regulators of the Wnt pathway, respectively. However, it is not clear how these two enzymes with opposing functions regulate Wnt signaling. Here we show that both CKIδ and CKIɛ interacted directly with Dvl-1, and that CKI phosphorylated multiple components of the Wnt-regulated β-catenin degradation complex in vitro, including Dvl-1, adenomatous polyposis coli (APC), axin, and β-catenin. Comparison of peptide maps from in vivo and in vitro phosphorylated β-catenin and axin suggests that CKI phosphorylates these proteins in vivo as well. CKI abrogated β-catenin degradation in Xenopus egg extracts. Notably, CKI decreased, whereas inhibition of CKI increased, the association of PP2A with the β-catenin degradation complex in vitro. Additionally, inhibition of CKI in vivo stabilized the β-catenin degradation complex, suggesting that CKI actively destabilizes the complex in vivo. The ability of CKI to induce secondary body axes in Xenopus embryos was reduced by the B56 regulatory subunit of PP2A, and kinase-dead CKIɛ acted synergistically with B56 in inhibiting Wnt signaling. The data suggest that CKI phosphorylates and destabilizes the β-catenin degradation complex, likely through the dissociation of PP2A, providing a mechanism by which CKI stabilizes β-catenin and propagates the Wnt signal.
Use of Irrigation in Selection for Soybean Yield Potential under Drought

The impact of selection in irrigated environments on improving seed yield in drought environments has not been extensively researched in soybean [Glycine max (L.) Merr.]. Our objectives were to evaluate cultivar x irrigation interaction, its impact on selection for yield in drought environments, and drought tolerance in soybean: drought tolerance being defined as better relative yield ranking in drought environments than in nondrought environments. Seven data sets were obtained from Arkansas trials of Maturity Group V cultivars. Each contained data from irrigated and nonirrigated trials from one location from two consecutive years with drought. Significance of genotype x irrigation interaction was determined for each set along with heritability of yield in both irrigation treatments and the genetic correlations of irrigated and nonirrigated yield from one year with nonirrigated yield in the other year. Rank correlations and crossover interactions between irrigation treatments were analyzed. The effect of selection in both irrigation treatments on yield in drought environments was simulated. Genotype x irrigation interaction was significant in six data sets. Entry-mean heritability was higher in the irrigated trials (0.74) than in nonirrigated trials (0.37). Rank changes between irrigated and nonirrigated treatments rarely consisted of large yield differences. The genetic correlations of yield from irrigated and nonirrigated trials from one year with yield from nonirrigated trials in another year were nearly equal. The results indicated that selection from irrigated trials would improve yield in drought environments better than selection from nonirrigated trials. Drought tolerant reactions occurred in only 16% of the two-cultivar comparisons. While several cultivars appeared tolerant, their yield in drought environments was not superior to several less tolerant cultivars. Nonirrigated trials may be useful in identifying a few unadapted cultivars.
Online Students' Expectations: Enhancing the Fit between Online Students and Course Design:

Learner analysis and needs assessments are basic elements of all instructional design models and are of concern to those designing distance education courses. Mismatches between students' expectations and actual course features may impact learning. This investigation surveyed 249 geographically dispersed online students for the course features they valued and the course features included in their distance education courses. Results revealed general agreement between course features desired by students and those included in their current courses, however, there were mismatches; particularly concerning the use of instant messaging, team assignments, and creating biography pages. Implications for online course design are presented.
Agents that cause enlargement of sebaceous glands in hairless mice. II. Ultraviolet radiation.

We have developed a murine model to measure the effects on sebaceous glands of ultraviolet (UV) radiation. Hairless mice were irradiated with Westinghouse FS-40 tubes filtered to attenuate the radiation below 290 nm. Emission was mainly in the UVB range (peak, 313 nm). Single and multiple exposures were given with fractions or multiples of one minimal erythemal dose (MED). Biopsies, fixed for light microscopy, were stained with H & E. Under high power, sebocytes of 30 glands per specimen were counted and the means determined. A single exposure of 1 MED caused a significant increase in sebocyte count, as did thrice-weekly exposures to 0.5 MED for 3 weeks. One 3-MED exposure produced sebocyte necrosis, yet 30 exposures at 4 MED failed to ablate the glands. In both cases there was rebound enlargement which had not returned to control levels by the end of the studies (24–30 weeks). Prolonged irradiation produced maximum enlargement in a few weeks. Thus, in a manner similar to other skin components, the response of sebaceous glands to UV radiation is one of hyperplasia.
Biological markers in panic states: lactate-induced panic and mitral valve prolapse.

Abstract Anxious patients, and more specifically, patients experiencing panic attacks, are thought to have a significant biological component to their illness. This study looks at two promising biological markers associated with this patient population—mitral valve prolapse and lactate-induced panic. We present our findings, which further characterize clinical and biological aspects of these two markers.
The giant dipole resonance excited by α-capture

Abstract We have studied the reactions 24Mg(α,γ)28Si from E α = 5.3 MeV to 14.5 MeV , 26 Mg(α,γ) 30Si from 4.0 MeV to 13.5 MeV and 28Si(α,γ)32S from 7.0 MeV to 12.0 MeV. These α-energies lead into the region of the giant dipole resonance in the compound nucleus. The yield of γ-rays leading to the ground state of the final nucleus, γ0, was studied for each of the three targets; and for 24Mg(α,γ) the radiation γ1 going to the first excited state was also studied with resonable accuracy. The angular distributions of γ0, which were measured in 100 keV steps over a wide range of energies for the 24Mg and 26Mg targets and at two energies for the 28Si target, showed a dominant electric-dipole transition. This indicates that the (α,γ0) reactions lead predominantly through the giant dipole resonance in 28Si and 30Si and most likely also in 32S. The gamma-ray yield, which was measured in steps of 30 or 100 keV over the energy ranges studied, exhibited strong fluctuations in each case. For α-capture both in 24Mg and 26Mg, statistical analysis of the fluctuations showed that the reactions proceed nearly 100% through compound-nucleus formation and that the average width of the compound-nucleus resonances is about 60 keV. The integrated cross sections of these three alpha-capture reactions led to the conclusion that formation of the giant resonance by alpha capture is strongly inhibited - even in cases in which the alpha capture is isospin allowed. This is expected since the giant dipole resonance is supposed to consist predominantly of particle-hole states. Earlier experiments of proton capture by 27Al had shown that only a small part of the giant dipole resonance in 28Si leaks into the more complicated nucleon configurations of the compound nucleus. The observation that this part of the giant dipole resonance in 28Si decays with comparable strength by α-particle and proton emission indicates that it has a strong admixture of isospin T = 0.
Recommendations for Physical Activity in Patients with Multiple Sclerosis

For many years, patients with multiple sclerosis (MS), an inflammatory demyelinating disease of the central nervous system, have been advised to avoid exercise. MS is believed to be autoimmune in origin, mediated by activated T cells which penetrate the blood-brain barrier and attack myelin. The pathophysiology, with respect to function is an impairment of saltatory conduction, specifically, slowing of conduction speed and/or conduction block. Symptoms can temporarily worsen on exposure to heat or during physical exercise.
Minimization of Oxidative Flavor Deterioration in Refrigerated, Batter‐Breaded Restructured Pork Nuggets by Glandless Cottonseed Flour in the Meat or Coating

Pork shoulders were restructured into nuggets with 0.5% NaCl, 0.25% polyphosphate and 3.0% water or with the three additives plus 1.5% defatted glandless cottonseed flour (GCF). Restructured nuggets were batter-breaded with either commercial coating ingredients or commercial ingredients plus GCF. The coated nuggets were prefried in vegetable oil and stored at 4°C for 0 or 9 days before reheating when needed. Thiobarbituric acid values and sensory warmed-over flavor scores of products showed that oxidative flavor deterioration in batter-breaded pork nuggets can be minimized by incorporating GCF into either the meat or the coating system. The GCF additions did not have adverse effects on coating pick-up and palatability.
Alternatives to Migration in the United States: Policy Issues and Economic Impact

Despite public opinion favoring reduced immigration, U.S. immigration policy since the 1980s has led to increased inflows of both legal and unauthorized immigrant workers, and migrants accounted for 12% of the U.S. population and 16% of its workforce in 2010. Given this disjuncture, this article explores practical alternatives to high levels of immigration in managing the U.S. workforce. The U.S. economy could reduce foreign-born employment by increasing employment among native workers, by increasing investment in technology and other enhancements to productivity, or by reducing production in immigrant-intensive industries. The article explores the feasibility of these alternatives in relation to current demographic and labor market conditions, possible policy tools, and the likely economic costs and benefits. The analysis reveals that the greatest economic benefits may be gained from enhancements to productivity, which would allow for reduced immigration without loss of output, whereas the reduction of U...
Bone mineral density in adolescent women using depot medroxyprogesterone acetate.

Purpose To present current data on bone mineral density (BMD) in adolescent women using the long-acting contraceptive depot medroxyprogesterone acetate (DMPA) and also to discuss the importance of developing maximal bone mass during adolescence to offset bone demineralization later in life. Data Sources Research-based articles in the medical literature, review articles, and recommendations from the American Academy of Pediatrics and the National Osteoporosis Foundation. Conclusions Osteoporosis is a preventable disease that affects millions of Americans, particularly older women. Factors influencing the attainment and maintenance of peak bone mass during childhood and adolescence affect the future risk of fractures. Although longitudinal studies conducted on adolescent women using DMPA are very limited, findings suggest that adolescents are losing bone density during a time of expected bone accretion. Implications for Practice Clinicians must consider all the risks and benefits when prescribing contraceptives to adolescents. By themselves, the findings related to BMD and DMPA use by adolescents are not sufficient to limit the use of DMPA as a contraceptive method. However, clinicians must take into account the addition of other modifying factors associated with BMD that may contribute to overall bone loss in adolescent females. More prospective data on the long-term use of DMPA by adolescents are needed to determine DMPA's effect on bone loss and to determine if bone loss is transient in adolescents.
Polar and auroral phenomena: a review of U.S. progress during 1979 - 1982.

The quadrennium 1979-1982 has been a highly active time in the field of polar and auroral research, with nearly 400 research papers and thirty general or topical review papers written by U.S. authors. This paper highlights progress in understanding auroral morphology, precipitating particle fluxes, the spectra and sources of upward-flowing particles, large-scale Birkeland currents, and theoretical and experimental advances in auroral-scale electrodynamics. Global electrodynamics, active experiments, plasma waves, and auroral aeronomy, although certainly 'polar and auroral phenomena', are discussed in other papers in this issue.
Stabilizing effect of caffeine on a respirationally unstable strain of yeast.

Abstract A respirationally unstable strain R6U2 of haploid yeast spontaneously produced respiration-deficient (RD) mutants in unusually high frequencies. Addition of small doses up to 1200 mg/l of caffeine to the culture media considerably reduced the production of RD mutants. The effect was only temporary and the RD mutants again appeared in high frequencies when the cultures were freed from caffeine. It was demonstrated that caffeine rendered the strain more stable and reduced the production of mutant progeny from the normal but unstable mother cells.
Synthetic Receptors For Anion Recognition

The recognition of anions using abiotic hosts is an area of interest in the field of molecular recognition, which recently has been rapidly expanding. The variety of shapes and sizes of anionic targets has resulted in rather elaborate receptor designs that have made it possible to investigate the properties of anion recognition. These efforts are directed towards modeling the molecular-recognition characteristics of enzymes and focused on industrial applications such as sensing and separation. Within this context, this paper focuses on research done within the Anslyn group directed at physical studies of recognition systems and the use of these data in other fields.
Credibility crises: the dollar in the early 1980s

Abstract From October 1979 to February 1985, forward rates systematically underpredicted the strength of the US dollar. In this paper we argue that the explanation of this phenomenon is the existence of a peso problem. We identify two peso problem periods. The first one is related to the change in monetary regime in October 1979 and to the private sector doubts about the Federal Reserve commitment to lower money growth and inflation. The second peso problem period is related to the private sector anticipation of the dollar's depriciation beginning in March 1985.
Compositions of three low-FeO ordinary chondrites: Indications of a common origin with the H chondrites

Abstract Burnwell, EET 96031, and LAP 04575 are ordinary chondrites (OC) that possess lower than typical olivine Fa content than has been established for the H chondrites (
Poisons and antidotes among the Taman of West Kalimantan, Indonesia

Etude sur la medecine traditionelle et indigene des Tamans en Kalimantan, Indonesie, concernant les poisons et antidotes utilises en cas de grave maladie. Les poisons et antidotes, faits d'huiles differentes, sont l'objet de traites et d'echanges, sont lies aux formules et paroles magiques et font partie de spheres de pouvoir.
Large-scale preparation of sodium-potassium ATPase from kidney outer medulla

Large-scale preparation of sodium-potassium ATPase from kidney outer medulla. Background Large amounts of Na,K-ATPase are needed for studies involving protein chemistry. Preparation of Na,K-ATPase from kidney by the widely used, rapid procedure of Jorgensen ( Biochim Biophys Acta 356:36-52, 1974; Methods Enzymol 156:29-43, 1988) includes labor-intensive dissection of tissue from the outer medulla and centrifugation into a step gradient of sucrose solution. Methods In a large-scale modification presented here, tissue was dissected with a surgical instrument, a rongeur, and centrifugation was simply a five times repeated differential centrifugation. The procedure took seven days and 68 person-hours of work. Results The yield of activity from 26 kg of whole kidneys was 6600 units (μmol Pi/min) in one preparation. The amount of protein was 240 mg and the specific activity was 28 μmol Pi/min per mg protein. Conclusions There is a significant saving of labor to obtain a product with a specific activity similar to that commonly obtained. The microsomal fraction may be useful for preparing other membrane proteins from the outer medulla.
COERCION, OWNERSHIP, AND THE REDISTRIBUTIVE STATE: JUSTIFICATORY LIBERALISM'S CLASSICAL TILT

Justificatory liberalism is liberal in an abstract and foundational sense: it respects each as free and equal, and so insists that coercive laws must be justified to all members of the public. In this essay I consider how this fundamental liberal principle relates to disputes within the liberal tradition on “the extent of the state.” It is widely thought today that this core liberal principle of respect requires that the state regulates the distribution of resources or well-being to conform to principles of fairness, that all citizens be assured of employment and health care, that no one be burdened by mere brute bad luck, and that citizens' economic activities must be regulated to insure that they do not endanger the “fair value” of rights to determine political outcomes. I argue in this essay: (1) a large family of liberal views are consistent with the justificatory liberals project, from classical to egalitarian formulations (but not socialist ones); (2) overall, the justificatory project tilts in the direction of classical formulations.
The Framework of Essences in Spinoza's Ethics

As is well known, Spinoza's ontology consists of the one substance and its modes, so that individuals such as me and my friends, and even our pets and our cars, are modes of the one substance.1 Mod...
Polymorphisms in the CRP gene moderate an association between depressive symptoms and circulating levels of C-reactive protein

Although many studies have found psychological depression associated with higher circulating levels of C-reactive protein (CRP), not all findings are consistent. Since DNA sequence variation in the CRP gene has also been shown to predict plasma CRP levels, we hypothesized that plasma CRP may covary with depressive symptomatology as a function of allelic variation in the CRP gene. We tested this hypothesis in 868 healthy community volunteers of European ancestry. Depressive symptomatology was measured using the Center for Epidemiological Studies-Depression (CESD) scale, and plasma CRP was assayed from whole blood. Three polymorphisms [rs1417938 (A/T), rs1800947 (C/G) and rs1205 (C/T)] were genotyped and three-locus haplotypes were generated. Regression models adjusting for demographic and lifestyle-related covariates showed no direct association of CESD depression scores with CRP. In regression models adjusting for age, gender, education, smoking status and statin use, one CRP haplotype (T-G-C) was associated with CRP level (p=0.014) and a second haplotype (A-G-T) showed marginal association (p=0.064, respectively). Neither haplotype was related to depressive symptoms. However, plasma CRP was predicted by the interaction of A-G-T haplotype with depressive symptomatology (p=0.009). Higher CESD scores were associated positively with CRP levels among individuals with the A-G-T haplotype (p=0.004). In secondary analyses, body mass index was found to partially account for the moderating effects of the A-G-T haplotype on the association of depression with circulating CRP. In conclusion, we found that haplotypic variation in the CRP locus moderates an association of depressive symptoms with circulating CRP, which is partially mediated by BMI.
Interstrand complex formation of purine oligonucleotides and their nonionic analogs: the model system of d(AG)8 and its complement, d(CT)8.

We have investigated the role of purines in interstrand complex formation with regard to substitution of the negatively-charged, phosphodiester backbone by a nonionic, internucleoside linkage. Using the purine oligomer, d(AG)8, its methylphosphonate analog, d(AG)8, and the complementary pyrimidine oligomer, d(CT)8, as a model system, the stoichiometry, conformation, and stability of complexes formed at pH 8 were studied by spectroscopic and electrophoretic methods. When there is only one oligomer species in solution, d(AG)8 behaves as a single-stranded molecule. In contrast, the d(AG)8 oligomer readily forms an intermolecular self-complex, particularly in the presence of magnesium ion. Using either purine oligomer, duplexes can form with the d(CT)8 strand which differ in terms of their conformation and in the dependence of their thermal stability on sodium and magnesium ions. All studies show that a stable triplex forms with a 1:2 d(CT)8:d(AG)8 stoichiometry which does not require high concentrations of s...
The X-Ray Spectra of VY Sculptoris Stars Are Not Blackbodies

Using ASCA data, we find, contrary to other researchers using ROSAT data, that the X-ray spectra of the VY Sculptoris stars TT Arietis and KR Aurigae are poorly fitted by an absorbed blackbody model but are well fitted by an absorbed thermal plasma model. The different conclusions about the nature of the X-ray spectrum of KR Aur may be due to differences in the accretion rate since this star was in a high optical state during the ROSAT observation but in an intermediate optical state during the ASCA observation. TT Ari, on the other hand, was in a high optical state during both observations and so directly contradicts the hypothesis that the X-ray spectra of VY Scl stars in their high optical states are blackbodies. Instead, based on theoretical expectations and the ASCA, Chandra, and XMM spectra of other nonmagnetic cataclysmic variables, we believe that the X-ray spectra of VY Scl stars in their low and high optical states are due to hot thermal plasma in the boundary layer between the accretion disk and the surface of the white dwarf, and we appeal to the acquisition of Chandra and XMM grating spectra to test this prediction.
Reference priors when the stopping rule depends on the parameter of interest

Priors related to Jeffreys's prior and the reference priors of Berger and Bernardo are developed for experiments where a stopping rule is given. These noninformative priors depend on a function of the expected stopping time. In a one-parameter experiment with a stopping rule, the Jeffreys prior is shown to be improved by taking the stopping rule into account, based on a criterion using frequentist coverage probabilities. In a multiparameter experiment, however, the Jeffreys prior depends on the stopping rule in an inappropriate fashion. In the latter case the reference prior effectively accounts for the stopping rule. The motivation for this work was in part the statistical importance of the problem and the lack of noninformative priors for experiments when a stopping rule is given, and in part a wish to develop an interesting application of a recently developed method of deriving reference prior by Berger and Bernardo.
Researchers consider U.S. Southwest's response to warmer, drier conditions

In 2000, the popular press frequently referred to reports that the southwestern United States might experience a shift from relatively wet to dry conditions during the next couple of decades (see http://topex-www.jpl.nasa.gov/discover/PDO.html). These predictions stemmed from observations that the Pacific Decadal Oscillation (PDO) appeared to abruptly change from a “positive” to a “negative” phase in 1999 (Figure 1). During the mid-twentieth century, a similar negative phase of the PDO was accompanied by prolonged dry conditions in the southwest. By extrapolation, some climatologists predicted future drought in the southwest. Such a change would heavily affect land use planning in the region, because national demographics have stressed the region's resources over the past century From 1990 to 2000, for instance, the population of Nevada and Arizona increased by almost 2.3 million people (http://www.census.gov/population/www/cen2000/respop.html). To discuss potential scenarios of landscape and ecosystem response to 25 years of hot and dry climate, scientists from diverse disciplines gathered at the University of Arizona in April 2001. The objectives of this workshop were to address evidence supporting predictions of warmer and drier climate and the possible landscape responses (http://geology.wr.usgs.gov/sw-workshop/).
Induction of genomic instability after an acute whole-body exposure of mice to 56Fe ions

Abstract The purpose of this study was to evaluate dose–response relationships for the in vivo induction of micronuclei (MN) as a measure of both initial radiation damage and the induction of genomic instability. These measurements were made in mouse blood erythrocytes as a function of radiation dose, radiation quality, time after irradiation, and the genetic background of exposed individuals. Blood samples were collected from two strains of mouse (CBA/CaJ and C57BL/6J) at different times up to 3 months following a whole-body exposure to various doses of 1 GeV/amu 56 Fe ions (0, 0.1, 0.5 and 1.0 Gy, at the dose rate of a 1 Gy/min) or 137 Cs gamma rays (0, 0.5, 1.0 and 3.0 Gy, at the dose rate of 0.72 Gy/min). Blood-smear slides were stained with acridine orange (AO). The frequencies of MN were measured in mature normochromatic-erythrocytes (MN-NCEs) and in immature polychromatic-erythrocytes (MN-PCEs). Effects of both types of radiation on erythropoiesis were also evaluated. As a measure of cell progression delay, a dose-dependent decrease in numbers of PCEs was observed at day 2 post-exposure in both strains, regardless of radiation quality. Subsequently, the levels of PCEs increased in all exposed mice, reaching control levels (or higher) by day 7 post-exposure. Further, at day 2 after the exposure, there was no increase in the frequency of MN-PCEs in CBA/CaJ mice exposed to 56 Fe ions while the frequency of MN-PCEs elevated as a function of dose in the C57BL/6J mice. At day 4, there was no dose related increase in MN-NCEs in either strain of mouse exposed to 137 Cs gamma rays. Additionally, at the early sacrifice times (days 2 and 4), 56 Fe ions were slightly more effective (per unit dose) in inducing MN-NCEs than 137 Cs gamma rays in CBA/CaJ mice. However, there was no increase in the frequency of MN-NCEs at late times after an acute exposure to either type of radiation. In contrast, both types of radiation induced increased MN-PCEs frequencies in irradiated CBA/CaJ mice, but not C57BL/6J mice, at late times post-exposure. This finding indicates the potential induction of genomic instability in hematopoietic cells of CBA/CaJ mice by both types of radiation. The finding also demonstrates the influence of genetic background on radiation-induced genomic instability in vivo.
A Novel Microstrip to Coplanar Waveguide Transition for Flip-Chip Interconnection using Electromagnetic Coupling

A novel compact microstrip to coplanar waveguide (CPW) transition is proposed for flip-chip interconnection. Broadband performance of the transition is simulated and agrees well with measured results. A good interconnection between microstrip line on a motherboard to CPW on a flip-chip is accomplished without any vias. For 10dB return loss, the microstrip-to-CPW transition and the microstrip-to-flip-chip interconnection present 170% and 140% bandwidth, respectively.
Quantum oscillations in the ultrasonic absorption in p-type PbSe

Abstract Analysis of quantum oscillations in the ultrasonic absorption in p-type PbSe indicates that the carriers are located in four equivalent 〈111〉 “ellipsoids”. At high carrier concentrations each “ellipsoid” appears to be compressed along its major axis.
Providing an analytic structure for key system design choices

The design of a system, especially a system architecture, requires the balancing of multiple performance parameters with the system cost and other implementation issues. Multi-attribute utility theory provides a structured, coherent framework for conducting an analysis in which system designs are evaluated on multiple performance parameters. This paper describes the application of multi-attribute utility analysis to the design of the Worldwide Digital Signal Systems Architecture (WWDSA), a telecommunications system, by the United States' Defense Communications Agency (now called the Defense Information Systems Agency). The advantages of using multi-attribute utility theory during the system design are highlighted. In addition, we discuss several key analytical issues that led to this application being a success in the eyes of the decision makers.
Morphological, Biochemical and Immunohistochemical Studies on Heart Development in Cardiac Mutant Axolotls, Ambystoma mexicanum

SYNOPSIS. A naturally-occurring genetic mutation, designated c for “cardiac lethal” in axolotls, Ambystoma mexicanum , is proving to be a useful model for studying myofibrillogenesis in differentiating heart cells. In this paper I describe morphological, biochemical and immunofluorescence studies which compare the contractile proteins in normal and mutant hearts. In addition, morphological studies on anterior endoderm, an important heart inductor tissue in salamanders, are reviewed. Detailed electron microscopic studies show that normal heart myocytes contain numerous well-organized myofibrils. Although mutant heart cells contain a few myosin and actin filaments, there are no organized myofibrils. Instead, amorphous proteinaceous collections are prominent in the peripheral cytoplasm of the cell where myofibrils would be expected to first form. SDS-polyacrylamide gel electrophoresis shows that actin is present in almost normal amounts in mutant hearts, myosin heavy chain is reduced and tropomyosin is virtually absent. Immunofluorescence studies reveal that myosin, α-actinin and tropomyosin are located prominently in theorganized myofibrils of normal heart cells. In mutant hearts myosin is localized almost exclusively in the amorphous collections at the cell peripheries, α-actinin also is distributed mainly in the peripheral cell cytoplasm. There is almost no staining for tropomyosin. Heavy meromyosin (HMM) binding experiments demonstrate that the actin in mutant heart cells is contained within the amorphous collections in a non-filamentous state and the addition of HMM causes its polymerization into filaments. In view of these findings, we undertook studies to determine whether there might be a causal relationship between theabsence of tropomyosin in mutants and the failure of actin to form into filaments. Our results indeed show that addition of tropomyosin to glycerinated mutant hearts or homogenates of mutant hearts causes the amorphous actin to form into filaments. Thus, this single gene mutation results in mutant heart cells having reduced, but significant, amounts of myosin and actin, even though non-filamentous, and substantial amounts of α-actinin. There is almost no tropomyosin. It is implied that the drastic reduction of tropomyosin in mutant cells is somehow related to the failure of normal myofilament formation, which in turn would seem to be an essential step in the normal organization of myofibrils.
Mathematics, Mind, and Necessity in Wittgenstein's Later Philosophy

Etude du concept de verite necessaire dans les ecrits logiques et mathematiques de Wittgenstein, qui engendre une conception de la personne fondee sur les lois de la pensee appartenant a un langage logico-mathematique ahistorique originaire au monde et a la vie humaine, d'une part, et qui decrit le comportement rationnel de la personne en fonction de l'activite complexe qui forme sa vie, d'autre part. Examinant l'idee d'un echafaudage de la pensee et du langage, ainsi que l'interpretation des regles et des pratiques constitutives, chez Wittgenstein, l'A. montre que sa philosophie tardive distingue la necessite logique de l'existence de la necessite physique du monde
The effect of bilirubin on the human platelet.

When platelets are obtained from the neonate or from adult subjects and incubated with indirect-reacting bilirubin, varying degrees of morphologic changes occur. These changes are platelet swelling and filamentous membrane formation frequently associated with platelet aggregation and even cell lysis. When platelets are pretreated with bilirubin and used in thromboplastin generation tests, impaired generation is noted. The addition of bilirubin to whole blood does not affect plasma coagulation factor assays but does impair or inhibit clot retraction. It is suggested that these abnormalities in morphology and platelet function are related to an inhibiting effect of bilirubin on ATP-ADP-dependent systems.
System-level abstraction semantics

Raising the level of abstraction is widely seen as the solution for closing the productivity gap in system design. They key for the success of this approach, however, are well-defined abstraction levels and models. In this paper, we present such system level semantics to cover the system design process. We define properties and features of each model. Formalization of the flow enables design automation for synthesis and verification to achieve the required productivity gains. Through customization, the semantics allow creation of specific design methodologies. We applied the concepts to system languages SystemC and SpecC. Using the example of a JPEG encoder, we will demonstrate the feasibility and effectiveness of the approach.
Interactions of Encephalitozoon cuniculi Polar Tube Proteins

Microsporidia are eukaryotic, obligate intracellular organisms defined by small spores that contain a single invasion organelle, the polar tube, which coils around the interior of the spore. When these parasites infect host cells, the polar tube is discharged from the anterior pole of the spore, pierces the cell, and transfers sporoplasm into the cytoplasm of the host. Three polar tube proteins (PTP1, PTP2, and PTP3) have been identified in this structure. The interactions of these proteins in the assembly and function of the polar tube are not known. This study was undertaken to examine the protein interactions of the Encephalitozoon cuniculi polar tube proteins (EcPTPs). Immunofluorescence and immunoelectron microscopy confirmed the colocalization of EcPTP1, EcPTP2, and EcPTP3 to the polar tube. Experiments using cross-linkers indicated that EcPTP1, EcPTP2, and EcPTP3 form a complex in the polar tube, which was confirmed by immunoprecipitation using EcPTP1 antiserum. Yeast two-hybrid analysis revealed that full-length EcPTP1, EcPTP2, and EcPTP3 interact with each other in vivo. Both the N and C termini of EcPTP1 were involved in these interactions, but the central region of this protein, which contains a repetitive motif, was not. Further studies of polar tube proteins and their structural interactions may help elucidate the formation of the polar tube during the invasion process.
Kinetics of dithionite reduction of the heme nonapeptide of cytochrome c.

Abstract The kinetics of dithionite reduction of the oxidized heme nonapeptide fragment of horse heart cytochrome c have been measured as a function of ionic strength at pH 7 and pH 9 by the stopped-flow technique. Dithionite concentration dependences indicate that the radical anion monomer, SO 2 XXX , is the active reductant. The pH 7 ionic strength dependence suggests that the heme peptide is reacting as a negatively charged molecule (its overall charge is calculated to be − 1). Comparison of these results with the known rate of dithionite reduction of cytochrome c indicates that the heme nonapeptide has substantially greater inherent reactivity than cytochrome c , perhaps due to the greater accessibility of the heme.
The cost of Pitt's Caribbean campaigns, 1793-1798.

In October I 796, it was claimed in the house of commons that almost every person in the country knew someone who had died in the military campaigns then being fought out in the Caribbean.' In less than four years, the government of William Pitt had sent well over 6o,ooo soldiers to the West Indies to reinforce the 6,ooo already stationed there. While fearing the threat to Britain's slave colonies of France's proselytizing revolutionaries, the ministry more particularly had hoped to profit from the political chaos in the French West Indies and to conquer these extremely valuable possessions for the British empire.2 The great influx of unacclimatized troops, however, fuelled a massive pandemic of yellow fever which raged throughout the Caribbean and decimated each wave of reinforcements.3 As early as August I 794, the level of mortalities in the West Indies had aroused public alarm, and by I796 rumours of the numbers dead and of the great costs incurred 'were topics of general conversation and complaint'.4 The Foxite whigs accused the government of weakening the country's defences in the greedy pursuit of overseas gains and of allowing troops to suffer through incompetence and neglect. A 'violent debate' took place in the commons in April but the ministry managed to avoid producing any mortality statistics.5 During the autumn, however, public disquiet increased. Rumours seeped back to Britain of huge losses suffered by the troops who had sailed with Sir Ralph Abercromby only nine months before in what was the greatest expedition ever to have left Great Britain. A correspondent of Edmund Burke informed him that, according to undisclosed official returns, IO,000 men had perished in just fifty-two days. It was at this time that Burke added to the later printings of his Regicide peace the famous line about fighting to conquer a cemetery.6 The names of officers who had died of yellow fever now appeared frequently in the obituary columns. In the October debates, British losses in the French colony of Saint Domingue (modern Haiti) were singled out for condemnation,7 for it was there that British policy had most signally failed. The following May, the whigs compelled the ministry
A miniaturized AC magnetic susceptometer for detecting biomolecules tagged to magnetic nanoparticles

We demonstrate a miniaturized AC magnetic susceptometer to detect biomolecules tagged to magnetic nanoparticles (MNPs). The proposed compact susceptometer measures the magnetic relaxation spectrum of biomolecules tagged with MNPs in an aqueous suspension. The relaxation time corresponds to the Brownian relaxation time and depends on the hydrodynamic size of the MNPs. Conventional susceptometers are bulky, expensive and are designed for extreme conditions (e.g. low temperature or high DC magnetic field). Our handheld prototype is composed of AC current source, precise millimeter sized differential sensing coils, and a ultra-sensitive lock-in amplifier. The performances were verified for 15, 25nm Fe 3 O 4 -COOH MNPs suspended in solution. The result for each sample show the peak frequency of imaginary susceptibility is inversely proportional to effective hydrodynamic size of MNPs.
Analysing narrative productions in older school-age children and adolescents with fetal alcohol syndrome: An experimental tool for clinical applications

The most devastating teratogenic effect of alcohol on the unborn child is fetal alcohol syndrome (FAS). FAS is a permanent birth defect that results in lifelong disruptions in cognitive, linguistic and social development. One of the most debilitating effects of prenatal alcohol exposure involves the development and use of social communication. Deficits in social communication jeopardize academic success and appear to play a major role in the maladaptive and dysfunctional behaviours present in older school-age children and adolescents with FAS. The ability to manage longer units of social discourse is a defining feature of adolescent language. Narratives are extended texts that occur frequently in the language of the classroom and in a variety of meaningful social contexts. The demands of narratives provide clinicians with a window of opportunity from which to examine the social-communicative processes of youngsters with FAS. In this paper we introduce an experimental protocol that has been designed to sam...
Modification of cysteine residues in vitro and in vivo affects the immunogenicity and antigenicity of major histocompatibility complex class I-restricted viral determinants.

In studying the subdominant status of two cysteine-containing influenza virus nuclear protein (NP) determinants (NP39–47 and NP218–226) restricted by H-2Kd, we found that the antigenicity of synthetic peptides was enhanced 10–100-fold by treatment with reducing agents, despite the fact that the affinity for Kd was not enhanced. Reducing agents also markedly enhanced the immunogenicity of cysteine-containing peptides, as measured by propagation of long-term T cell lines in vitro. Similar enhancing effects were obtained by substituting cysteine with alanine or serine in the synthetic peptides, demonstrating that sulfhydryl modification of cysteine is responsible for the impaired antigenicity and immunogenicity of NP39–47 and NP218–226. We found similar effects for two widely studied, cysteine-containing peptides from lymphocytic choriomeningitis virus. The major modifications of cysteine-containing synthetic peptides are cysteinylation and dimerization occurring through cysteine residues. We demonstrate that both of these modifications occur in cells synthesizing a cytosolic NP218–226 minigene product and, further, that T cells specific for cysteinylated NP218–226 are induced by influenza virus infection in mice, demonstrating that this modification occurs in vivo. These findings demonstrate that posttranslational modifications affect the immunogenicity and antigenicity of cysteine-containing viral peptides and that this must be considered in studying the status of such peptides in immunodominance hierarchies.
Hormonal Control of Gene Expression in the Ovary

The maturation of ovarian follicles involves several sequential stages: initiation, growth, selection, ovulation, and luteinization (Fig. 1). Although the factor(s) that initiates the growth of “resting” primordial follicles remain elusive, the key endocrine events controlling follicular growth in mammals have been known for many years. For example, once follicles have begun to grow, basal concentrations of the gonadotropins, FSH and LH, maintain growth up until the small antral stage. Small antral follicles are selected to continue growth by subtle increases in basal concentrations of gonadotropins, such as those that occur at menses in primates (1) or at the end of pregnancy in rodents (2). Once selected, the growing dominant follicle(s) acquires specific functional characteristics that permit it to differentiate to the preovulatory stage and synthesize estradiol. Increased serum estradiol triggers the surge of gonadotropins that, in turn, stimulates the preovulatory follicle(s) to ovulate and luteinize...
Using computer conferencing to improve productivity in the 90s

Three case studies in the use of computer conferencing are discussed. The first use of conferencing is for the exchange of ideas among the members of a tightly knit project team. The second case involves the use of a computer conference to conduct a task force to a rapid conclusion at minimal cost. The process and results are discussed for both. The third use of conferencing is an experiment underway to improve communications and manage a large group of projects that have the involvement of three separate, and sometimes contending, organizations spread over two countries. >
Dexrazoxane-associated risk for secondary malignancies in pediatric Hodgkin's disease: a claim without compelling evidence.

TO THEEDITOR: The title of a recent article by Tebbi et al 1 claims that dexrazoxane poses a risk, and that it is responsible for a higher incidence of secondary acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) and other second malignant neoplasms (SMNs) in children with Hodgkin’s disease (HD) treated with dexrazoxane plus doxorubicin, bleomycin, vincristine, and etoposide (ABVE) or dose-intensified ABVE with prednisone and cyclophosphamide (ABVE-PC) as well as radiotherapy (POG 9426 [low-stage HD] and 9425 [advanced-stage HD]). This claim is based on 10 SMNs (including eight AML/MDS) in 478 patients. Differences in the incidence of SMNs between children randomly assigned to receive dexrazoxane versus no dexrazoxane concomitantly with chemotherapy to evaluate its efficacy as a cardiopulmonary protectant show no statistical significance by simple Fisher’s exact tests (of 239 patients, eight [3.35%] v two [0.84%] with SMNs, respectively, and P .11; six [2.51%] v two [0.84%] with AML/ MDS, respectively, and P .24), nor by the more conventional and appropriate time-to-event analysis used by the authors (P .06 for SMNs;P .16 for AML/MDS). Only after adjusting for race, age, and sex in a different analysis using a Poisson regression model were the authors able to achieve aP value below .05 for any type of SMN (P .02 for SMNs; P .10 for AML/MDS), even though the authors demonstrated no imbalance between arms for race, age, or sex. We would regard this as scant statistical evidence, particularly in a trial that, as the authors observe, was not “designed for statistical comparison of leukemia and SMN risk.” 1 Dexrazoxane is a US Food and Drug Administration–approved, established protectant against doxorubicin-induced cardiotoxicity in patients with breast cancer 2 and is also cardioprotective in acute lymphoblastic leukemia of childhood, 3 as well as with other malignancies. 4 No evidence shows that this protection has impaired the effectiveness (survival) of doxorubicin-treated patients or that it has caused any new or clinically relevant sequelae (infection, hemorrhage, deaths, or necessity for change of dosage). Some 16 clinical trials in seven different countries over the past 10 years involving more than 500 patients have not reported a single case of AML as a result of combining dexrazoxane with doxorubicin plus fluorouracil and cyclophosphamide (the FAC regime). 4