cssi/SciSciGPT-SciSciNet huggingface dataset:
Placing an upper limit on cryptic marine sulphur cycling

The oxygen isotopic composition of seawater sulphate in oxygen-deficient waters records the degree of in situ sulphur cycling. The sulphur cycle has been suggested to play an important part in closing the marine fixed nitrogen budget in oxygen-deficient regions of the ocean. This paper combines oxygen and sulphur isotope data of seawater sulphate and modelling work and finds that previous estimates for sulphur-driven remineralization and fixed nitrogen loss are near the upper limit for what is possible taking into account in situ sulphate isotope data. A quantitative understanding of sources and sinks of fixed nitrogen in low-oxygen waters is required to explain the role of oxygen-minimum zones (OMZs) in controlling the fixed nitrogen inventory of the global ocean. Apparent imbalances in geochemical nitrogen budgets1 have spurred numerous studies to measure the contributions of heterotrophic and autotrophic N2-producing metabolisms (denitrification and anaerobic ammonia oxidation, respectively)2,3. Recently, ‘cryptic’ sulphur cycling was proposed as a partial solution to the fundamental biogeochemical problem of closing marine fixed-nitrogen budgets in intensely oxygen-deficient regions4. The degree to which the cryptic sulphur cycle can fuel a loss of fixed nitrogen in the modern ocean requires the quantification of sulphur recycling in OMZ settings. Here we provide a new constraint for OMZ sulphate reduction based on isotopic profiles of oxygen (18O/16O) and sulphur (33S/32S, 34S/32S) in seawater sulphate through oxygenated open-ocean and OMZ-bearing water columns. When coupled with observations and models of sulphate isotope dynamics and data-constrained model estimates of OMZ water-mass residence time, we find that previous estimates for sulphur-driven remineralization and loss of fixed nitrogen from the oceans are near the upper limit for what is possible given in situ sulphate isotope data.
2-5A antisense treatment of respiratory syncytial virus

Although a prominent cause of upper and lower respiratory tract disease in infants and the elderly, clinical options for treatment of respiratory syncytial virus (RSV) infections remain limited. Historically, attempts to develop vaccines have been unsuccessful, and rapid viral mutation rates have stifled development of several small molecule-based antiviral agents. Thus, targeted approaches to block RSV replication, including humanized monoclonal antibodies and nucleic acid-based strategies (antisense and RNA interference), have emerged as potentially viable drug development options.
Periapical inflammation and bacterial penetration after coronal inoculation of dog roots filled with RealSeal 1 or Thermafil.

Abstract Introduction The purpose of this study was to subject 2 carrier-based root filling products to a 4-month microbial challenge in a dog model with histologic markers to assess periapical inflammation and bacterial penetration of the 2 filling materials. Histologic evidence of bacterial penetration and periapical inflammation were the outcome parameters used to compare the products. Methods Teeth were aseptically prepared and then filled with carrier-based Resilon (RealSeal 1 [RS-1], n = 25) or with carrier-based gutta-percha (Thermafil, n = 25) and were left exposed for 4 months. The first control group received a coronal seal over either RS-1 or Thermafil root fillings (n = 8). A second control group was instrumented and left completely empty (n = 8). Results Histologic evidence of periapical inflammation was observed in 29% of the Thermafil group and in 9% of the RS-1 group. This difference was only significant when controlling for a possible tooth position effect on inflammation presence ( P P P = .002). Conclusions RS-1 appeared to resist bacterial penetration more effectively than Thermafil under the conditions of this study.
Discovering and managing quantitative association rules

Although association rule mining has been studied in the literature for quite a while and numerical attributes are prevalent, perhaps surprisingly, the state-of-the-art quantitative association rule mining is rather inefficient and ineffective in discovering all useful rules. In this paper, we propose a novel divide and conquer two-phase algorithm, which is guaranteed to find all good rules efficiently. We further devise an optimization technique for performance. Moreover, we discuss a few issues with managing and using the discovered quantitative association rules. We perform a comprehensive experimental study which shows that our algorithm is one to two orders of magnitude faster than the state-of-the-art one. In addition, we discover significantly more rules that are useful for prediction.
Railroads: Recent Books and Neglected Problems

I. The qualities a textbook should have, 152. — Estimation of Vanderblue, 156; Jones, 156; Haney, 157; Miller, 159. — II. Neglected Problems: governmental problem, 160; division of through rates, 162; terminals, 163; physical geography, 164; other fields of transportation than railroads, 165.
Static Inventory Models and Inflationary Cost Increases

(1980). Static Inventory Models and Inflationary Cost Increases. The Engineering Economist: Vol. 26, No. 2, pp. 91-112.
Independent tuning of quality factor and unity-gain frequency in a transconductance-capacitance integrator

It is shown that the quality factor and unity-gain frequency of a recently proposed transconductance-capacitance integrator can be tuned practically independently of each other, without using extra devices. Computer simulation is used to verify the concept.
Heparin inhibition and polyamine stimulation of a glycogen synthase kinase (PC0.7) from rabbit skeletal muscle.

Abstract A rabbit skeletal muscle glycogen synthase kinase, designated PC 0.7 ( A. A. DePaoli-Roach, Z. Ahmad, and P. J. Roach, 1981, J. Biol. Chem. 256 , 8955–8962 ), has been shown to belong to that class of casein and phosvitin kinases inhibited by heparin. The heparin concentration required for half-maximal inhibition (I 0.5 ) was in the range 0.04–0.15 μg/ml when glycogen synthase, phosvitin, or β-casein A were substrates for phosphorylation. Heparin also inhibited (I 0.5 = 0.05 μg/ml) the previously observed autophosphorylation of the β-subunit ( M r 25,000) of the protein kinase. The enzyme was also affected by the polyamines spermine and spermidine, but less so by putrescine. With glycogen synthase or β-casein A as substrates, spermine and spermidine stimulated PC 0.7 activity although the extent depended on Mg 2+ concentration. With phosvitin as substrate, spermine and spermidine activated at low Mg 2+ levels but spermine inhibited at higher Mg 2+ concentrations. KCl at 0.05 to 0.15 m considerably alleviated heparin inhibition, and also tended to reverse spermine effects on measured activity. Histone and spermine suppressed the inhibition by heparin. Heparin and polyamine effects on PC 0.7 are thus interdependent and also modified by various factors including ionic strength, Mg 2+ , and histone. Careful consideration must be given to such interactions in assessing any possible physiological relevance of effectors such as heparin or polyamines.
Scaling behaviour in the growth of companies

A SUCCESSFUL theory of corporate growth should include both the external and internal factors that affect the growth of a company1–18. Whereas traditional models emphasize production-related influences such as investment in physical capital and in research and development18, recent models10–20 recognize the equal importance of organizational infrastructure. Unfortunately, no exhaustive empirical account of the growth of companies exists by which these models can be tested. Here we present a broad, phenomenological picture of the dependence of growth on company size, derived from data for all publicly traded US manufacturing companies between 1975 and 1991. We find that, for firms with similar sales, the distribution of annual (logarithmic) growth rates has an exponential form; the spread in the distribution of rates decreases with increasing sales as a power law over seven orders of magnitude. A model wherein the probability of a company's growth depends on its past as well as present sales accounts for the former observation. As the latter observation applies to companies that manufacture products of all kinds, organizational structures common to all firms might well be stronger determinants of growth than production-related factors, which differ for companies producing different goods.
Size disparity in pediatric lung transplantation

Donor scarcity and the limitations of organ preservation dictate that a wide size range be used to maximize effective donor utilization in pulmonary transplantation. Problems of size disparity are magnified in the pediatric population, where relevant dimensions vary considerably by age. There have been 10 pediatric lung recipients (7 bilateral, 2 single, 1 heart-lung) at our institution since 1991. The age range was 3 to 26 years (mean, 13.7), and the weight range was 15 to 57 kg (mean, 33.6). Diagnoses included cystic fibrosis (5), pulmonary fibrosis (2), pulmonary hypertension (2), and arteriovenous malformation (1). The donor-to-recipient weight ratio ranged from 0.45 to 1.9, and the donor-to-recipient thoracic height ratio ranged from 0.6 to 1.6. Lobar resection and delayed chest closure was required in one case and was successful. Cardiopulmonary bypass was used electively in seven cases. No reexplorations for bleeding were necessary. Two of the three hospital deaths resulted from right ventricular failure, judged to be secondary to excessive pulmonary artery pressures intraoperatively associated with small donor allografts. Elective bypass had not been used. Inhaled nitric oxide (6 patients) and/or extracorporeal membrane oxygenation (2 patients) were used for temporary postoperative support. The hospital survival rate was 70% (7/10). One late death occurred 14 months postoperatively and was caused by obliterative bronchiolitis. The authors conclude that size disparity is a significant problem in pediatric lung transplantation. However, with elective use of cardiopulmonary bypass and aggressive postoperative support, a broad size range can be used.
Radial head prosthesis micromotion characteristics: Partial versus fully grit-blasted stems.

Background Compared to fully textured prosthetic stems, partial texturing lessens bone loss due to stress shielding and makes removal easier. However, initial press-fit stability is necessary for bone ingrowth. Hypothesis There is no significant difference in the initial stability of radial head prostheses that are partially grit-blasted compared to those that are fully grit-blasted. Materials and methods Cadaveric radii were implanted with partial or fully grit-blasted radial head prostheses. Micromotion of the stem at the isthmus of the canal and stem tip were measured under circumstances simulating eccentric loads. Results Micromotion was not significantly different in the fully grit-blasted stems (isthmus, 11 ± 1 μm; tip, 21 ± 2 μm) and partially grit-blasted stems (isthmus, 13 ± 2 μm; tip, 25 ± 2 μm) ( P = 0.4). The direction of loading had no effect on micromotion characteristics in either the fully or partially grit-blasted stems ( P = .07). Discussion Micromotion is comparable in partially and fully grit-blasted radial head prosthetic stems. For both stem surfaces, micromotion was well within the range that is conducive for bone ingrowth. A partially textured stem might have less bone loss due to stress shielding, making it easier to remove without destroying bone. Conclusion The initial stability of a radial head stem that is partially grit-blasted only at the proximal end is comparable to that of a radial head stem that is grit-blasted along its entire length.
A hydrophobic site in human prothrombin present in a calcium-stabilized conformer.

Human prothrombin and prothrombin fragment 1 were demonstrated to bind to Phenyl-TSK columns in the presence of 5.0 mM calcium ions but not in the presence of either magnesium ions or manganese ions. The calcium-dependent interaction of prothrombin fragment 1 is markedly reduced upon oxidation of approximately one mole of tryptophan per mole of protein. The ability of prothrombin fragment 1 to inhibit prothrombin activation by factor Xa in the presence of calcium ions and phospholipid is also markedly reduced by reaction with N-bromosuccinimide. These results provide the first demonstration of a calcium-specific site in prothrombin outside of the “GLA domain”.
The suspension notation for lambda terms and its use in metalanguage implementations

Abstract Many metalanguages and logical frameworks have emerged in recent years that use the terms of the lambda calculus as data structures. A common set of questions govern the suitability of a representation for lambda terms in the implementation of such systems: α-convertibility must be easily recognizable, sharing in reduction steps, term traversal and term structure must be possible, comparison and unification operations should be efficiently supported and it should be possible to examine terms embedded inside abstractions. Explicit substitution notations for lambda calculi provide a basis for realizing such requirements. We discuss here the issues related to using one such notation—the suspension notation of Nadathur and Wilson—in this capacity. This notation has been used in two significant practical systems: the Standard ML of New Jersey compiler and the Teyjus implementation of λ-Prolog. We expose the theoretical properties of this notation, highlight pragmatic considerations in its use in implementing operations such as reduction and unification and discuss its relationship to other explicit substitution notations.
Whose dignity, which capacity?

Although no consensus exists on health policy issues, most people can agree that health care spending in the United States is excessive and unsustainable. In 2010, the United States spent $2.6 tril...
Inexpensive, semi‐automated system for measuring mechanical properties of soft tissues

Stiffness and strength are important properties of many tissues, but standard material-testing equipment is expensive, often ill-suited for testing soft tissues, and rarely accessible to biologists. We describe a system built around a microcomputer and an electronic balance which is particularly well-suited for measuring stress and strain in small samples of soft tissue. We use a discarded floppy disk drive as a linear actuator to strain the sample, while an electronic balance measures the tension (used to calculate stress). We give an algorithm for a program to drive a microcomputer which controls the floppy disk drive via its parallel port and records the balance measurements via its serial port. We used this system to obtain stress-strain curves from a sample of latex rubber and a sample of soft insect cuticle. Three tests of the rubber sample gave nearly identical results, with smooth, J-shaped stress-strain curves. The stress-strain curves gave a modulus elasticity value of 1.72 Mpa over the steep, straight region, well within the range for natural latex rubber. We also tested a sample of abdominal cuticle from a caterpillar (Manduca sexta). The caterpillar cuticle had a J-shaped stress-strain curve with a modulus of elasticity of 2.11 Mpa over the steep part of the curve. J. Exp. Zool. 284:374–378, 1999. © 1999 Wiley-Liss, Inc.
UV laser photochemistry of CF2Cl2

Abstract The focused ArF laser irradiation of CF 2 Cl 2 at room temperature has been investigated and emission from the CF(A 2 Σ + -X 2 Π), CF(B 2 Δ-X 2 Π), and CF 2 ( 1 B 1 -X 1 A 1 ) systems has been found. Also, under conditions of a high pressure of Ar diluent, C( 1 P 1 - 1 S 0 ) emission has been noted.
Do genes on rat chromosomes 9, 13, 16, 18, and 20 contribute to regulation of breathing?

As part of a large scale, high through-put physiologic genomics study, we sought to determine whether genes on rat chromosomes 9, 13, 16, 18, and 20 contribute to phenotypic differences in the control of breathing between two inbred rat strains (SS/Mcw and BN/Mcw). Through a chromosomal substitution breeding strategy, we created 5 consomic rat strains (SS.BN9, SS.BN13, SS.BN16, SS.BN18, and SS.BN20), which were BN/Mcw homozygous at only one chromosome and SS/Mcw homozygous at all other chromosomes. Standard plethsmography was used to assess eupneic breathing and ventilatory responses to CO2 (FiCO2=0.07) and hypoxia (FiCO2=0.12), and PaCO2 during treadmill exercises provided the index of the exercise hyperpnea. There were no robust differences in eupneic breathing between any strains. The ventilatory response to CO2 was 150% greater (P<0.001) in the SS/Mcw rats than in the BN/Mcw rats and all consomic strains had the SS/Mcw phenotype. Hyperventilation during hypoxia did not differ between the parental and the consomic strains, but ventilation during hypoxia was greater (P<0.001) in the SS/Mcw than in the BN/Mcw, and the SS.BN9, and SS.BN18 appeared to acquire this BN/Mcw phenotype. The hyperventilation during treadmill walking was greater (P<0.006) in the BN/Mcw and the SS.BN18 rats than in the SS/Mcw rats. Finally, the duration of the apnea following an augmented breath (post sigh apnea, PSA) was greater (P<0.001) in the BN/Mcw and the SS.BN9 rats than all other strains. We conclude that the robust difference between the parental strains in ventilatory CO2 sensitivity is not due to genotypic differences on the 5 chromosomes studied to date, but genotypic differences on chromosomes 9 and 18 contribute to differences in ventilatory responses to hypoxia, exercise, and/or to the differences in the PSA.
Measuring product category involvement: A multitrait-multimethod study

Several scales have been developed to measure consumer product involvement. Little research, however, has been done to validate these operationalizations. The present study used data from 106 students at 2 points in time to assess the convergent, discriminant, and criterion-related validity of 3 of these measures: Zaichkowsky’s Personal Involvement Inventory, Laurent and Kapferer’s Consumer Involvement Profile Inventory, and Mittal’s Involvement Scale. A multitraitmultimethod matrix analysis provided evidence for the convergent and discriminant validity of the 3 product involvement scales. All 3 scales also showed discriminant validity with 2 measures of global, marketplace involvement. Correlations with several criterion measures demonstrated criterion-related validity. Whereas the Zaichkowsky scale possessed excellent internal consistency, the Mittal scale may also be used because of its short length, convenience, and validity. The Laurent and Kapferer scale possesses validity, but had lower internal consistency.
Microposts With Embedded Nanowires to Control Substrate Stiffness

Cells can sense the stiffness of their substrate and respond through mechanotransduction pathways that lead to changes in cell contractility1. Studies to measure the mechanical response of cells have been primarily performed on passive substrates that do not change stiffness as a cell matures. This paper presents a novel substrate that has local regions of higher stiffness. In the current setup, polymer microposts are stiffened with nickel nanowires in random locations. An experiment was run with cells seeded onto the posts which resulted in a promising trend of an increase in cell force per post as the percentage of stiff posts seen by the cell increased.Copyright © 2012 by ASME
Nonlinear optical transmission of nanographene and its composites

Low-cost broad-band optical limiters based on nanographene have been studied, finding optical-limiting properties superior to those of current standards, carbon fullerenes (C60) solutions and carbon black suspensions. Further examination indicates that the presence of π conjugation improves the optical-limiting responses. Superior limiting performance is retained regardless of solvent viscosity and polarity, a unique feature of graphene not observed in C60 and carbon black. Graphene suspensions in organic solvents can work under 10 Hz laser pulses without losing excellent limiting performance. More significantly, outstanding limiting properties are also preserved in a gel matrix. These nanographene-based optical limiters can thus work in solutions and solid matrixes for devices used for protecting human eyes and optical sensors from high-power lasers.
Misorientation and tetragonal distortion in heteroepitaxial vapor-Grown III–V structures†

Heteroepitaxial deposits of III–V vapor phase epitaxy (VPE) alloys on (001) substrates have been found to exhibit distortions such that: 1. the epitaxial layers are not parallel to the substrate but are inclined to it by as much as 2°, and 2. the epitaxial lattice is tetragonally distorted normal to the substrate with c/a ratios as high as 1.003. These effects habe been observed in non-graded (abrupt) and in compositionally graded (both step and continuous) layers of InxGa1−xP, GaAsxP1−x, and InxGa1−xAs on GaAs and GaP substrates and vary with the amount of lattice mismatch. Misorientation is shown to be a general phenomena in VPE growth associated with relieved lattice mismatch (regardless of the grading technique employed), whereas tetragonal distortion is felt to be a manifestation of the Poisson effect normal to the substrate associated with unrelived lattice mismatch and is shown to be dependent on grading technique. Possible device effects are also discussed. Es wurde gefunden, das durch Dampfphasenepitaxie abgeschiedene heteroepitaxiale III–V-Legierungen auf (001)-Substraten Verzerrungen in folgender Weise zeigen: 1. Die epitaxialen Schichten liegen nicht parallel zum Substrat, sondern sind zu ihm um etwa 2° geneigt, 2. Das Gitter der Epitaxieschicht ist normal zum Substrat tetragonal verzerrt mit c/a-Verhaltnissen bei 1,003. Diese Effekte wurden sowohl in nicht-graduierten (abrupten) als auch in verbindungsmasig graduierten (stufenweise oder kontinuierlich) Schichten von InxGa1−xP, GaAsxP1−x und InxGa1−xAs auf GaAs- und GaP-Substraten beobachtet und verandern sich mit dem Betrag der Gitter-Fehlanpassung. Es wird gezeigt, das Fehlorientierung allgemein bei Dampfphasenepitaxie auftritt und mit „abgebauter” (z. B. durch Versetzungen) Gitter-Fehlanpassung verbunden ist (unabhangig von der benutzten Gradationstechnik), wahrend tetragonale Verzerrung ein Ausdruck des Poisson-Effektes normal zum Substrat zu sein scheint, mit „nicht-abgebauter” Gitter-Fehlanpassung verbunden und abhangig von der Gradationstechnik ist. Mogliche Effekte in Halbleiterbauelementen werden auch diskutiert.
UPCONVERSION SPECTROMETRY FOR ASTROPHYSICAL APPLICATIONS

Black body measurements and absorption spectra of methane near 3.3 microns are presented and used as examples in a discussion of upconversion spectrometry for astrophysical application. Factors determining the system conversion efficiency and the minimum detectable flux for a typical system are presented. The spectrometer described uses an Argon-ion laser and a temperature turned LiNbO3 crystal in a CW mode. Satisfactory agreement between measured and calculated performance parameters is obtained. An estimate of the highest performance parameters attainable using current technology is given.
An assessment of the emissions inventory processing systems EMS-2001 and SMOKE in grid-based air quality models.

Abstract In the United States, emission processing models such as Emissions Modeling System-2001 (EMS-2001), Emissions Preprocessor System-Version 2.5 (EPS2.5), and the Sparse Matrix Operator Kernel Emissions (SMOKE) model are currently being used to generate gridded, hourly, speciated emission inputs for urban and regional-scale photochemical models from aggregated pollutant inventories. In this study, two models, EMS-2001 and SMOKE, were applied with their default internal data sets to process a common inventory database for a high ozone (O3) episode over the eastern United States using the Carbon Bond IV (CB4) chemical speciation mechanism. A comparison of the emissions processed by these systems shows differences in all three of the major processing steps performed by the two models (i.e., in temporal allocation, spatial allocation, and chemical speciation). Results from a simulation with a photochemical model using these two sets of emissions indicate differences on the order of ±20 ppb in the predic...
Economic burden and disparities in healthcare resource use among adult patients with cardiac arrhythmia.

Background As of 2012, approximately 4.3 million Americans experience some form of cardiac arrhythmia (CA). Assessment of economic burden and healthcare resource use on the overall CA population is limited.
Singing Against Apartheid: ANC Cultural Groups and the International Anti-Apartheid Struggle*

This article explores the ways in which music, together with cultural forms such as poetry, theatre and dance, was used to garner international support for the struggle against apartheid. It focuses on two of the African National Congress's most significant projects in this realm: Mayibuye, an agitprop group that achieved considerable success in Europe in the 1970s; and Amandla, which travelled widely as a party ambassador during the 1980s, offering large-scale performances incorporating music, theatre and dance. A central motivation for the article was documenting the work of these two ensembles, both of which made significant contributions to the development of cultural activity and yet remain virtually undocumented in the history of the movement and the struggle. The article's primary analytical interest is in how black South African popular culture came to play a role in the movement's work in exile, how it was recruited and re-packaged in order to appeal to foreign audiences, and the relationship bet...
Investigating the classroom learning environment of resilient and non-resilient students from inner-city elementary schools

Abstract The serious educational, community, and family problems facing students in urban cities present a formidable challenge to educators. One factor that has been found to be positively associated with student achievement in inner-city schools is the quality of the classroom learning environment. The study reported in this chapter addresses the problems of students in these schools by drawing upon two distinct and emerging theoretical frameworks: educationally resilient students and classroom learning environments. The results of the study indicated that resilient students had higher motivation and more positive perceptions of their learning environments.
The Influence of Dormancy‐Inducing Desiccation Treatments on the Respiration and Germination of Sorghum

Seeds of sorghum (Sorghum vulgare Pers.) dried in a forced-air dryer from an initial moisture content of 12 percent to either 10 percent or 7 percent exhibited physiological dormancy. Dormancy was more marked in seeds dried to 7 percent than to 10 percent moisture, and was more pronounced in germination at 15° or 20° than at 25°C. Expression of dormancy at the lower temperatures was influenced decidedly by the four germination media (paper towels, blotters, sand, and soil). Percent dormancy was lowest in towels and highest in soil. Osmotic tension is suggested to be a factor influencing dormancy in these media. Dormancy was relieved by cutting the integumentary membrane or by rehydration of dried seeds. Respiration rates were lower and respiratory quotients higher in dormant seeds than in the controls. Differences in respiration rates were detected within 2 hours after the start of imbibition. Dormancy and differences in respiration rates appear to be associated with changes induced in the seeds by drying.
Thermal analysis and measurement of a solar pond prototype to study the non-convective zone salt gradient stability

Abstract Solar ponds combine solar energy collection with long-term storage and can provide reliable thermal energy at temperature ranges from 50 to 90 °C. A solar pond consists of three distinct zones. The first zone, which is located at the top of the pond and contains the less dense saltwater mixture, is the absorption and transmission region, also known as the upper convective zone (UCZ). The second zone, which contains a variation of saltwater densities increasing with depth, is the gradient zone or non-convective zone (NCZ). The last zone is the storage zone or lower convective zone (LCZ). In this region, the density is uniform and near saturation. The stability of a solar pond prototype was experimentally performed. The setup is composed of an acrylic tube with a hot plate emulating the solar thermal energy input. A study of various salinity gradients was performed based on the Stability Margin Number (SMN) criterion, which is used to satisfy the dynamic stability criterion. It was observed that erosion of the NCZ was accelerated due to mass diffusion and convection in the LCZ. It can be determined that for this prototype the density of the NCZ is greatly affected as the SMN reaches 1.5.
Oligomerization of ethene and propene over composite zeolite catalysts

Abstract The conversion of ethene and propene over a series of composite zeolite catalysts has been studied in a fixed-bed reactor. The composite catalysts were synthesized by incorporating 1 to 10 wt.-% of HAlZSM-5 (molar ratio SiO2/Al2O3=35) zeolite in a silica-alumina matrix. The silica-alumina matrix contained 15 wt.-% Al2O3 and was prepared by the cogelation method. Pure ethene and propene were used as the feed gases. Experiments were conducted over a temperature range of 200 to 600°C at a space velocity of 3.4±0.1 galkene/gcatalyst/h and atmospheric pressure. In addition, a few experiments were carried out at the space velocities of 34 and 68 h−1. For all the catalysts, ethene and propene conversion increases with increasing reaction temperature. In the case of propene, the conversion increases rapidly over a narrow temperature range, for a ZSM-5 zeolite content of 10 wt.-%. However, a moderate increase with temperature was observed when ethene was the reactant and the composite catalyst had a zeolite loading of less than 10 wt.-%. With both reactants, silica-alumina catalysts containing 5 and 10 wt.-% ZSM-5 exhibited activities much greater than the pure silica-alumina. The selectivity of the reaction remained comparable to that of silica-alumina however, not of HAIZSM-5. The concomitant formation of aromatic hydrocarbons and lower alkanes (C1–C4), indicates that hydrogen transfer reactions occur on all catalysts. This transfer reaction is sensitive to the zeolite content of the composite. Both the amorphous silica-alumina and the pure HAIZSM-5 zeolite exhibit high aromatization activity, because of hydrogen transfer, whereas, at intermediate zeolite loading (5 wt.-%), the hydrogen transfer activity is lower, resulting in higher alkenes. For both the 5% and 10% zeolite composites, the coke content expressed as a percentage of the converted propene was less than 1.5 wt.-%, a value close to that for the pure HAIZSM-5 zeolite. In contrast, the amorphous silica-alumina as well as the 1.5 wt.-% of zeolite composite resulted in a larger coke fraction. Furthermore, the temperature-programmed oxidation profiles indicate that the coke could be oxidized more easily in the case of 5% zeolite composite than the 10% zeolite composite or the pure zeolite.
Comparisons of ectomycorrhizae on pinyon pines (Pinus edulis; Pinaceae) across extremes of soil type and herbivory

Using field and greenhouse studies, we examined the relationships among pinyon pines (Pinus edulis), their ectomycorrhizal mutualists, and their moth herbivores as a function of soil fertility. We studied two soil types-the ash and cinder soils of the San Francisco volcanic field and nearby sandy loam soils. In the field, pinyons growing in cinders suffered from reduced moisture, negative nitrogen mineralization rates, low phosphate levels, reduced growth, and high moth herbivory relative to pinyons growing in sandy loam. Pinyons growing in cinders also had twofold higher levels of ectomycorrhizal colonization than their noncinder counterparts. Similarly, in the greenhouse, seedlings grown in cinders had higher levels ofectomycorrhizal colonization and greater numbers of ectomycorrhizae than seedlings grown in sandy loam. Seedling shoot growth was significantly enhanced by ectomycorrhizae in both soils. These patterns support three conclusions. First, field and greenhouse studies demonstrated that trees growing in nutrient-poor soils had higher levels of ectomycorrhizal colonization than trees growing in better soils. Second, across soil types, variation in ectomycorrhizal colonization was better predicted by soil fertility than by herbivory. However, herbivory negatively affected ectomycorrhizae in the stressful cinder environment. Third, although mycorrhizae can be parasitic under some conditions, ectomycorrhizae had mutualistic impacts on pinyon seedlings across the environmental extremes we studied.
Pharmacokinetic and Toxicity Studies of AZT (Zidovudine) Following Perfusion of Human Term Placenta for 14 Hours

Multiple exposures to AZT (Zidovudine) for 14 hr were examined in the dually perfused human term placental lobule in order to determine the pharmacokinetics of transfer, as well as several viability parameters of toxicity. In each experiment, three separate additions of AZT at a concentration of 3.8 mM was added to the maternal reservoir, and perfusate samples were obtained from both the maternal and the fetal compartments for determinations of AZT, glucose, lactate, oxygen, and human chorionic gonadotropin (hCG) concentrations. During 14 hr of continuous exposure to this high concentration of AZT, the production of hCG was significantly reduced by 75% when compared to the 2-hr control period before the administration of AZT. In addition, lactate production was reduced by 45% after AZT administration. Such changes in hCG and lactate production were not observed in separate experiments conducted over the same time interval, but with no AZT added. Based upon a lack of total perfusion fluid loss, changes in fetal arterial pressure, and histopathology, placental lobule integrity was maintained throughout the perfusion period. Further, AZT readily crossed the placenta into the fetal compartment reaching equilibrium with maternal levels within 60-90 min after addition of each administration of AZT. Based upon AZT levels in the fetal perfusate, AZT does not accumulate against a concentration gradient and therefore appears to be diffusion limited. Placental tissues obtained from perfused, partially perfused, and nonperfused regions at the conclusion of the experiment were analyzed for AZT levels. Substantial AZT levels in the nonperfused tissues indicated that AZT is a freely diffusible compound. The results of the current study demonstrate that high concentrations of AZT alter placental function resulting in reduced production of hCG and lactate.
Creep Strain Measurement of an Actual Leadfree Solder Interconnect Using Digital Image Correlation

Creep behavior of the solder joint is one of the critical concerns in reliability of the electronic package, especially above half of the homologous temperatures. Considering melting point of the lead free solder alloys, creep deformation can be dominantly occur even at room temperature.Among the three phase of the creep curve, the steady state strain rate in secondary phase is the most important design parameter to predict life time of the solder joint. To measure the strain rate of the solder during the creep deformation, several studies conducted creep test using bulk solder samples. However, mechanical properties of the bulk solder are different from actual solder joint due to its microstructure and intermetallic layer. Thus, creep behavior of the actual solder ball need to be measured to obtain the realistic creep data. In this study, the constant creep rate of the actual solder ball in ball grid array (BGA) packages is measured using 2D Digital Image Correlation (DIC) measurement technique.Three lead free BGA packages, SAC105, SAC305 and Sn/Cu/Ni alloy (SCN) are used for the creep test. While 9.78 N, 19.56 N, and 29.34 N of the compressive loads are applied at 20°C, 40°C, 60°C and 90°C to each type of the specimen, a microscopic images of the cross sectioned surface of the solder ball are captured. The series of images are sequentially taken during the predetermined time interval and transferred to DIC software to generate full-filled surface displacement data. From the displacement data, constant creep rate of the actual solder ball is acquired.Copyright © 2012 by ASME
Lithospheric structure across the Transantarctic Mountains constrained by an analysis of gravity and thermal structure

The Transantarctic Mountains demarcate the boundary between the highly extended lithosphere of the West Antarctic Rift System and the Proterozoic East Antarctic Craton. Although the last stage of relief development was in the Eocene, the TAM retain peak elevations in excess of 4500 m. This combination of old age and high relief are difficult to reconcile, and the mechanism(s) responsible for uplift and support of this mountain range remain elusive and controversial. Recent seismic studies provide key constraints on the crustal structure. Here we constrain the lithospheric structure across this boundary by forward modeling of the gravity based on a density structure that reflects the thermal structure. Our results show that the observed very-long wavelength (>500km) gravity anomaly can be modeled by a West Antarctic lithosphere ~60 km thick, and an East Antarctic lithosphere ~250 km thick. In addition, the gravity anomaly associated with the TAM can be modeled by including the thermal effects of heat producing elements concentrated in the crust.
Angiotensin II Type 2 Receptors and Nitric Oxide Sustain Oxygenation in the Clipped Kidney of Early Goldblatt Hypertensive Rats

Angiotensin-converting enzyme inhibitors (ACEIs) decrease the glomerular filtration rate and renal blood flow in the clipped kidneys of early 2-kidney, 1-clip Goldblatt hypertensive rats, but the consequences for oxygenation are unclear. We investigated the hypothesis that angiotensin II type 1 or angiotensin II type 2 receptors or NO synthase mediate renal oxygenation responses to ACEI. Three weeks after left renal artery clipping, kidney function, oxygen (O 2 ) use, renal blood flow, renal cortical blood flow, and renal cortical oxygen tension (Po 2 ) were measured after acute administration of an ACEI (enalaprilat) and after acute administration of ACEI following acute administration of an angiotensin II type 1 or angiotensin II type 2 receptor blocker (candesartan or PD-123,319) or an NO synthase blocker ( N G -nitro-l-arginine methyl ester with control of renal perfusion pressure) and compared with mechanical reduction in renal perfusion pressure to the levels after ACEI. The basal renal cortical Po 2 of clipped kidneys was significantly lower than contralateral kidneys (35±1 versus 51±1 mm Hg; n=40 each). ACEI lowered renal venous Po 2 , cortical Po 2 , renal blood flow, glomerular filtration rate, and cortical blood flow and increased the renal vascular resistance in the clipped kidney, whereas mechanical reduction in renal perfusion pressure was ineffective. PD-123,319 and N G -nitro-l-arginine methyl ester, but not candesartan, reduced the Po 2 of clipped kidneys and blocked the fall in Po 2 with acute ACEI administration. In conclusion, oxygen availability in the clipped kidney is maintained by angiotensin II generation, angiotensin II type 2 receptors, and NO synthase. This discloses a novel mechanism whereby angiotensin can prevent hypoxia in a kidney challenged with a reduced perfusion pressure.
Resilient image sensor networks in lossy channels using compressed sensing

Data loss in wireless communications greatly affects the reconstruction quality of wirelessly transmitted images. Conventionally, channel coding is performed at the encoder to enhance recovery of the image by adding known redundancy. While channel coding is effective, it can be very computationally expensive. For this reason, a new mechanism of handling data losses in wireless multimedia sensor networks (WMSN) using compressed sensing (CS) is introduced in this paper. This system uses compressed sensing to detect and compensate for data loss within a wireless network. A combination of oversampling and an adaptive parity (AP) scheme are used to determine which CS samples contain bit errors, remove these samples and transmit additional samples to maintain a target image quality. A study was done to test the combined use of adaptive parity and compressive oversampling to transmit and correctly recover image data in a lossy channel to maintain Quality of Information (QoI) of the resulting images. It is shown that by using the two components, an image can be correctly recovered even in a channel with very high loss rates of 10%. The AP portion of the system was also tested on a software defined radio testbed. It is shown that by transmitting images using a CS compression scheme with AP error detection, images can be successfully transmitted and received even in channels with very high bit error rates.
Metalloproteinases Damage the Insulin Receptor to Cause Insulin Resistance in Spontaneously Hypertensive Rats

The elegant study by Delano and Schmid-Schonbein1 points to a potentially very important overlap of an insulin resistance mechanism with hypertension in the spontaneously hypertensive rat (SHR). Their investigation will likely be important to both the obese and hypertensive populations. With the national and international emphasis on obesity and its attendant cardiovascular problems, there is a tendency to forget that essential hypertension affects about the same percentage of humans as does serious obesity and an even higher percentage of the population than does type 2 diabetes mellitus. Obesity leading to insulin resistance and, in severe situations, type 2 diabetes mellitus, does have a genetic predisposition that the patient’s lifestyle can mitigate. However, hypertension even in the lean population has an established genetic basis and often develops despite every attempt to avoid inappropriate lifestyle issues. There is obviously an overlap of the obese and hypertensive genetic populations and likely a sharing of some mechanisms to cause many of their common vascular and cardiac pathologies. The existence of insulin resistance in the SHR came to attention in 1988 by a study by Horl et al.2 At the time, this seemed rather unusual, because the SHR is generally quite lean, and the dependence of insulin resistance on some degree of obesity was a common concept. In 1991, Reaven and Chang3 and Reaven4 questioned whether the insulin resistance leads to hypertension or vice versa in the SHR and hypertensive humans. The interest in hypertension and insulin resistance since 1988 has generated >200 articles dealing with various issues of insulin resistance in the SHR with something of the order of 5000 articles on insulin resistance and blood pressure abnormalities in humans and animals. We in clinical and basic sciences have been so well informed on this issue that we collectively take …
The Course and Prognosis of Different Types of Chronic Airflow Limitation in a General Population Sample from Arizona: Comparison with the Chicago “COPD” Series

Recently reported data from a general population study in Tucson, Arizona have shown that subjects who have an “asthmatic bronchitic” type of chronic airways obstruction have a much more benign course than equally impaired subjects who have the typical smoking-induced, and presumably emphysematous, form of disease. These data are reviewed briefly. Findings in these subjects are then compared with those in “COPD” patients enrolled in an “emphysema clinic” in Chicago many years ago; patients with asthmatic features had been systematically excluded from the Chicago series. The rate of decline in FEV1 and mortality of Arizona subjects considered to have “typical COPD” were remarkably similar to those in the Chicago series after accounting for age and initial FEV1, but Arizona subjects with features suggesting “chronic asthmatic bronchitis” had a much more favorable prognosis than either of the “COPD” groups. These different forms of chronic airways obstruction should be distinguished in clinical or epidemiolo...
The Illinois Underground Storage Tank Fund: Tanks for Nothing

At the expense of those who use petroleum in Illinois, the Underground Storage Tank (UST) Fund provides tank owners and operators with the financial support they need to remediate leaking UST sites. Little has been written on the sociodemographic factors that influence UST site remediation because most analysts characterize “open” tank sites (those in need of remediation) using only descriptive statistics. I examine how socioeconomic variables and the passage of time influence the distribution of open sites within Illinois and find that only time contributes to the likelihood that a site will remain open. This result suggests that reducing the reimbursement timeline for tank owners and operators should be considered as an effective strategy for increasing remediation rates, both within Illinois and throughout the United States. Related Articles Neill, Katharine A., and John C. Morris. 2012. “A Tangled Web of Principals and Agents: Examining the Deepwater Horizon Oil Spill through a Principal–Agent Lens.” Politics & Policy 40 (4): 629-656. http://onlinelibrary.wiley.com/doi/10.1111/j.1747-1346.2012.00371.x/abstract Pautz, Michelle C. 2009. “Trust between Regulators and the Regulated: A Case Study of Environmental Inspectors and Facility Personnel in Virginia.” Politics & Policy 37 (5): 1047-1072. http://onlinelibrary.wiley.com/doi/10.1111/j.1747-1346.2009.00210.x/abstract Shrock, Peter. 2010. “Changes in Relationships between State Characteristics and Regulatory Enforcement over Time.” Politics & Policy 38 (5): 991-1013. http://onlinelibrary.wiley.com/doi/10.1111/j.1747-1346.2010.00261.x/abstract Related Media DeHaan, Patrick. 2012. “Illinois Gas Prices Now the Highest in Continental U.S.” CBS. August 7. http://chicago.cbslocal.com/2012/08/07/illinois-gas-prices-now-the-highest-in-continental-u-s/ Illinois Environmental Protection Agency. 2008. Illinois Underground Storage Tank Fund Guide. May. http://www.epa.state.il.us/land/lust/ust-fund.html