cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of PEG-based Biocompatible Polymers on the Response of Lipid Vesicles under External Stimuli

Cell membrane dysfunction due to loss of structure integrity is the pathology of tissue death in trauma, muscular dystrophies, reperfusion injuries and common diseases. It is now established that certain PEG-based biocompatible polymers, such as Poloxamer 188, Poloxamine 1107 and PEG, are effective in sealing of injured cell membranes, thus can prevent acute necrosis if delivered timely after injury. Despite these broad applications of PEG-based polymers for human health, the fundamental mechanisms how PEG-based polymers interact with cell membranes are still under debate. Here, the effects of PEG-based biocompatible polymers on phospholipid membrane integrity under external stimuli (osmotic stress and oxidative stress) were explored using model cell membranes - giant unilamellar vesicles. Through fluorescence leakage assays and time-lapse fluorescence microscopy, we directly monitored the loss of structural integrity of single fluorescent dye-loaded GUVs under different stimuli, and observed the effects of triblock copolymers on these damaged membranes. We find that the interaction of the polymers with the lipid membrane involves two stages: an adsorption (I) and an insertion (II) state. We propose that the adsorption of the polymers on the membrane surface is responsible for the cell membrane resealing process due to its corralling effect, which is evidenced by slow-down of surface hydration dynamics upon adsorption of the polymers. In the insertion state, on the other hand, the polymers disturb the packing of phospholipids due to the mismatch in size and hydrophobicity of the PPO block with the lipid hydrocarbon tails, increasing the membrane permeability. Our results indicate that the biomedical application of PEG-based polymers, either as cell membrane resealing agents or as accelerators for drug delivery, is directed by the delicate balance between the adsorption and insertion of the polymers to the cell membranes.
Evolution and Robots

Long discusses his use of autonomous robotic fish to study vertebrate biomechanics and evolution.
Stimulated chloride transport by isolated parietal cells.

Abstract A preparation of rabbit parietal cells has been shown to respond to effectors of gastric acid secretion. The cells were isolated, aligned at the interface of two aqueous phases, and the transport of Cl− from one phase to the other effected by the cells under various pharmacological stimuli, was measured. Ca2+, in contrast to Mg2+, was shown to be necessary to elicit a response with histamine. This response was inhibited by prostaglandin E1. Dibutyryl cyclic AMP was without effect. Carbachol and catecholamines also stimulated secretion, but this was not inhibited by prostaglandin E1. Because basal Cl− transport in the presence of Ca2+ is in a direction opposite to that of the stimulated transport (and to the low basal transport in the presence of Mg2+), at least two secrection mechanisms appear operative.
Measurement Of Ground State Copper Density Using Hook Spectroscopy

The density of ground state copper atoms has been measured in an operating large-bore copper laser using hook spectroscopy. In this method, dispersion, due to the copper resonance lines at 327.4 nm and 324.7 nm, is measured by placing the copper laser tube in one arm of a Mach-Zehnder interferometer illuminated by a broad bandwidth UV source. The light source was a Nd:YAG-laser-pumped dye laser which was modified to have a 15 nm bandwidth and then frequency doubled in a 3 mm thick KDP crystal, resulting in a UV beam with an 8 nm bandwidth. The Nd:YAG laser was synchronized with the copper laser, allowing a time resolution of 8 ns. Copper density was measured both as a function of time and as a function of radial position across the bore of the tube. The radial resolution was about 2 mm. The space-dependent data gives information about the gas temperature distribution since the density is inversely proportional to the temperature. The gas temperature distribution found in this way agrees well with the predictions of a simple heat-conduction model which assumes uniform power deposition. The power deposition found in this way was compared to that found by calorimetry.
ILP in the undergraduate curriculum

The paper discusses the teaching of instruction level parallelism (ILP) in undergraduate electrical engineering (EE) and computer engineering (CpE) curricula. An argument is made for justifying the teaching of this topic, usually taught in graduate courses, at the undergraduate level. A detailed account of the way this topic is actually taught at the author's University is given. The paper discusses the specific ILP subjects, presented to the students, along with the technical literature sources used.
Thoracoscopic lobectomy is associated with lower morbidity than open lobectomy: A propensity-matched analysis from the STS database

Background Several single-institution series have demonstrated that compared with open thoracotomy, video-assisted thoracoscopic lobectomy may be associated with fewer postoperative complications. In the absence of randomized trials, we queried the Society of Thoracic Surgeons database to compare postoperative mortality and morbidity following open and video-assisted thoracoscopic lobectomy. A propensity-matched analysis using a large national database may enable a more comprehensive comparison of postoperative outcomes. Methods All patients having lobectomy as the primary procedure via thoracoscopy or thoracotomy were identified in the Society of Thoracic Surgeons database from 2002 to 2007. After exclusions, 6323 patients were identified: 5042 having thoracotomy, 1281 having thoracoscopy. A propensity analysis was performed, incorporating preoperative variables, and the incidence of postoperative complications was compared. Results Matching based on propensity scores produced 1281 patients in each group for analysis of postoperative outcomes. After video-assisted thoracoscopic lobectomy, 945 patients (73.8%) had no complications, compared with 847 patients (65.3%) who had lobectomy via thoracotomy ( P P = .0004], reintubation [n = 18 (1.4%) vs 40 (3.1%); P = .0046], and blood transfusion [n = 31 (2.4%) vs n=60 (4.7%); P = .0028], as well as a shorter length of stay (4.0 vs 6.0 days; P P Conclusions Video-assisted thoracoscopic lobectomy is associated with a lower incidence of complications compared with lobectomy via thoracotomy. For appropriate candidates, video-assisted thoracoscopic lobectomy may be the preferred strategy for appropriately selected patients with lung cancer.
Digital extraction of interference fringe contours.

Two basic techniques for extracting interferogram contours have been discussed. The first is a global contour extracton technique based on the fast Fourier transform. The second extracts individual contours with a thinning algorithm using logical neighborhood transformations. (AIP)
Numerical Simulation of Gas Phase Growth Environment of Carbon Nanotube Synthesis by Plasma-Enhanced Chemical Vapor Deposition

The gas-phase growth environment of carbon nanotubes has been simulated using different published chemical reaction mechanisms for a gas mixture of methane and hydrogen. Detailed chemical analysis of the growth environment is important in identifying precursor species responsible for CNT formation and is useful in understanding fundamental mechanisms that ultimately could allow control of the CNT synthesis process. The present simulations seek to compare the roles of different gas phase reaction mechanisms and to identify precursors for CNT formation. The results show that inlet methane-hydrogen mixture converts primarily to a acetylene-hydrogen mixture, and C2 H2 , CH3 , H2 , and H are the main precursors formed in the plasma under experimentally verified CNT growth conditions in a microwave plasma reactor.© 2005 ASME
A New azacyanocarbon, C4N4: tricyanomethanimine

Abstract - 2,2-Dichloroethylene-1,1-dicarbonitrile reacted with sodium azide to give 2,2- diazidoethylene-1,1-dicarbonitrile, which underwent thermolysis to give tricyanomethanimine, C 4 N 4 . The latter is as reactive as TCNE toward electron-rich molecules.
The 'RASor's' edge: Ras proteins and matrix destruction in arthritis

The shared characteristics of rheumatoid arthritis (RA) and cancer, particularly their unchecked growth and invasive behaviors, have been apparent for some time. However, the molecular mechanisms underlying these similarities are not clear. In a recent issue of Arthritis Research & Therapy, Abreu and colleagues link a well-studied oncogene, Ras, with expression of matrix metalloproteinase-3 (MMP-3) in RA. Their study correlates expression of the Ras guanine nucleotide exchange factor RasGRF1 with MMP-3 expression in RA synovium. They elucidate a potential mechanism of regulation of MMP-3 expression in RA, suggesting a potential target for RA treatment.
Formed Visual Hallucinations After Metrizamide Myelography

About 12 hours after a 77-year-old woman underwent metrizamide myelography of the posterior fossa to elucidate the cause of downbeat nystagmus, she developed formed visual hallucinations consisting primarily of brightly colored geometric shapes, cloud formations, and human figures. Her white blood cell count was 26,000/mm% 3% and her serum creatine phosphokinase level was markedly increased to 438 units/liter. Two days later, the hallucinations had subsided, the white blood cell count had decreased to 17,000/mm% 3% , and the serum creatine phosphokinase level had decreased to 105 units/liter. The hallucinations were probably caused by penetration of the metrizamide into the temporal lobe and visual association cortex.
Recall as a function of method of presentation and individual differences in test anxiety

Subjects differing in test anxiety had four free recall trials with a list of words that could be organized by associates or rhymes. The words were presented in a simultaneous display, with related items either grouped together spatially or separated. Anxiety deficits in organization previously observed with single-item presentation were reduced, but low-anxiety subjects still recalled a greater number of words. Blocking related items led to superior performance overall, but spatial arrangement did not interact with anxiety level.
Pulmonary embolism and portal vein thrombosis in an immunocompetent adolescent with acute cytomegalovirus hepatitis

Cytomegalovirus infection is usually asymptomatic or resembles infectious mononucleosis with fever, pharyngitis, arthralgias, lymphadenopathy, and atypical lymphocytosis. Even though primary CMV infection is usually self-limited in healthy individuals, significant complications can develop in immunocompromised patients. Venous or arterial thromboembolic phenomena are uncommon, yet very serious complications of CMV infection. Most published reports describe immunosupressed patients after organ transplantation or in the presence of HIV co-infection. However, thrombotic events in CMV infected immunocompetent individuals may occur. We describe the case of an immunocompetent adolescent with acute cytomegalovirus hepatitis that was complicated with pulmonary embolism and portal vein thrombosis. To our knowledge, this is the first reported case in which these two thrombotic phenomena occurred simultaneously in an adolescent with no obvious predisposing factors for thrombosis in the setting of an acute CMV infection.
Reports of severe physical punishment and exposure to animal cruelty by inmates convicted of felonies and by university students

A self-report questionnaire designed to assess abusive childhood environments and exposure to animal cruelty was administered to 314 inmates in a prisoner classification center. Although high rates of physical punishment characterized the entire sample, persons charged with violent, but nonhomicidal crimes reported more severely punitive childhood histories than those charged with homicidal crimes, sex offenses, and nonviolent offenses. Some exposure to animal cruelty was widespread in the sample, but there was no association between experiencing animal cruelty and the type of crime committed. Moreover, there were only modest associations between animal cruelty experiences and the aversive childhood histories of the subjects, as well as the subjects' reported use of physical and sexual coercion in dating and intimate relationships. To determine whether the high base rate of exposure to animal cruelty was unique to the incarcerated sample, a follow-up study was completed with university undergraduates. Widespread exposure to some animal cruelty was reported by undergraduates; there were modest associations between reporting animal cruelty and reporting punitive and acrimonious childhood histories. In general, the findings were consistent with the hypothesis that there is an association between punitive childhood histories and antisocial behavior but not consistent with the hypothesis that exposure to animal cruelty is importantly related to antisocial behavior or child maltreatment.
Meiofaunal prominence and benthic seasonality in a coastal marine ecosystem.

The muds of a shallow (7 m) site in Narragansett Bay, Rhode Island contained higher abundances of meiofauna (averaging 17×106 individuals per m2 and ash free dry weight of 2.9 g/m2 during a 3 year period) than have been found in any other sediment. The majority of sublittoral muds, worldwide, have been reported to contain about 106 individuals per m2. This difference is attributed primarily to differences in sampling techniques and laboratory processing.Extremely high meiofaunal abundances may have also occurred because Narragansett Bay sediments were a foodrich environment. While the quantity of organic deposition in the bay is not unusually high for coastal waters, this input, primarily composed of diatom detritus, may contain an unusually high proportion of labile organics. Furthermore, meiofauna could have thrived because of spatial segregation of meiofauna and macrofauna. While meiofauna were concentrated at the sediment-water interface, most macrofauna were subsurface deposit feeders. Macrofaunal competition with, and ingestion of meiofauna may thus have been minimized.The seasonal cycles of meiofauna and macrofauna were similar. Highest abundances and biomass were observed in May and June and lowest values in the late summer and fall. Springtime increases of meiofaunal abundance were observed in all depth horizons, to 10 cm. We hypothesize that phytoplankton detritus accumulated in the sediment during the winter and early spring, and that the benthos responded to this store of food when temperatures rose rapidly in the late spring. By late summer, the stored detritus was exhausted and the benthos declined.
HIGH TEMPERATURE TESTING OF NICKEL WIRE BONDS FOR SiC DEVICES

ABSTRACT This paper reports our effort to study the failure mechanisms and high temperature behavior of Ni wire bonds. Ultrasonicwire bonding was used to bond 25 tm-diameter Ni wire to 7500A-thick Ni pads deposited on 3C-SiC substrates. A series ofhigh temperature experiments which include electrical characterization, annealing tests, and in situ pull tests were conductedto test the reliability of the wire bonds at temperatures up to 55OC. In situ pull tests were also performed on samplesprepared by thermosonic wire bonding. Scanning electron microscope (SEM) was used to investigate the formation of brittlecracks on the heel of the bonds, to compare the feet of new and used wedges, and to examine the surface texture of wirebonds exposed to high temperatures.Keywords: Wire Bonding, Silicon Carbide, Nickel, High Temperature, Pull Test, Ultrasonic Wire Bonding, ThermosonicWire Bonding, Wedge, Brittle Cracks. 1. INTRODUCTION The lack of a durable wire bonding technology is a major impediment to the implementation of SiC-based microfabricateddevices for high temerathre applications. We have recently developed a Ni wire bonding process suitable for SiC deviceswith Ni contact pads . Our process uses conventional wire bonding tools and wire diameters. To the best of our knowledge,the only other wire bonding process developed specifically for high temperature SiC devices uses 250 tm-diameter Al wire2,which is much larger than the 25 p.m-diameter wires used in conventional Au and Al wire bonding.Ni is attractive as a contact metal for high temperature SiC devices in that Ni has a melting temperature of l453C, forms anohmic contact to both n-type and p-type 3C-SiC substrates and is also available in wire diameters similar to that of the Aland Au bonding wires (e.g., 25 jim). For high temperature applications, it is desired that the contact pad and the wire be ofthe same material because intermetallic growth and interface corrosion, which can occur between dissimilar metals at hightemperatures3, results in a rapid degradation of bond strength and a shift in the principal failure mode from wire breaks tobond lifts. The stability of the wire bonds is threatened by such a problem, especially at elevated temperatures. Therefore,reliability should be improved when pad metallization and bonding wires are ofthe same material.
Bridging the Technology Gap: Building a Development Model for Rural Alaska

Using results from a three-year (2003–2006) National Science Foundation ”Partnership for Innovation“ project undertaken in Native Alaska, this paper addresses if and how Information Technologies (IT) can be incorporated into indigenous, geographically isolated environments in order to bring positive social and economic benefit to those who are often seen as the “victims,” rather than the beneficiaries, of economic globalization. Specifically, we argue that the merchandizing of Native crafts and their effective marketing via ecommerce may be used not to supplant indigenous social and economic structures but rather, to enhance and strengthen them. We conclude the paper with the acknowledgment that such change may be slow in coming, and that development in Native Alaska must be viewed as a long-term undertaking.
Effects of neonatal estrogen exposure on prostatic secretory genes and their correlation with androgen receptor expression in the separate prostate lobes of the adult rat.

Brief administration of estrogen to newborn rats permanently restricts prostatic growth and testosterone sensitivity in adulthood. Previous work demonstrated that neonatal exposure to estradiol benzoate produced lobe-specific imprints in prostatic androgen receptor (AR) expression. Epithelial cell AR was markedly reduced or absent in the adult ventral and dorsal lobes, which correlated with a lack of epithelial differentiation and responsiveness. While the lateral lobe also showed reduced growth and testosterone responsiveness after neonatal estradiol benzoate, normal cell differentiation and AR levels were observed within the adult epithelium. To determine the impact that these receptor imprints have on the functional capacity of adult tissue, we herein examined the expression of lobe-specific, androgen-dependent, or androgen-responsive secretory genes in prostates of rats given neonatal estradiol benzoate and directly compared this with epithelial cell AR using histological techniques. Sprague-Dawley ra...
Screening for Hazardous/Harmful Drinking and Depressive Symptoms in an At-Risk Emergency Department Population

Although co-occurring alcohol use and depression have been identified in many populations, wide-spread screening for these disorders has not occurred in many Emergency Departments (EDs). Co-morbidi...
Recall of Mathematical Problem Information: Solving Related Problems

When solving a new problem, a successful problem solver presumably uses information, procedures, and more general notions that have been obtained from previous experience and training. Gestalt psychologists (Duncker, 1945; Luchins, 1942) have demonstrated that prior experience with related problems may have a negative effect in certain new problem-solving situations. In recent years, attention has been focused on identifying the circumstances under which positive transfer occurs. Reed, Ernst, and Banerji (1974) examined performance on the "Missionaries and Cannibals" problem and one of its homomorphs and reported that subjects exhibited positive transfer between the similar problems only when they were told of the relationship between the problems and only when they solved the more difficult problem of the pair first. Kulm and Days (1979) used an information-theoretic approach to study transfer between problems with related structures. They reported that significant transfer occurred when subjects solved an equivalent puzzle problem (Missionaries and Cannibals) but not an equivalent algebraic problem. However, significant transfer was reported when solving a similar algebraic problem but not a similar puzzle problem. The solution of related problems appeared to help subjects focus on relevant strategies, but different problem contexts appeared to interfere with transfer. Simon and Hayes (1976) also reported that the "cover story," or problem context, may have a significant effect on a subject's problem-solving performance. All the investigations cited above involved college students and, with the exception of an algebraic problem in the Kulm and Days study, all involved the solution of puzzle problems-Missionaries and Cannibals, Tower of Hanoi, and their isomorphs or homomorphs. The present study sought to extend this work by using school-age subjects and mathematical word problems of the kind usually encountered in school. Furthermore, the study looked specifically at the role of memory in transfer between related problems.
Xylose and arabinose utilization by the rumen bacterium Butyrivibrio fibrisolvens.

The rumen bacterium Butyrivibrio fibrisolvens strain D1 co-utilized xylose and glucose in batch culture, but there was a marked preference for glucose over arabinose. When both pentoses were provided, xylose was preferred over arabinose. Strain D1 co-utilized a combination of either pentose and cellobiose, but preferred pentoses over maltose. Pentose sugars were depleted less rapidly in the presence of sucrose than controls containing only pentose. In contrast, B. fibrisolvens strain A38 exhibited a strong preference for disaccharides, including maltose, over either xylose or arabinose. Theoretical maximum growth yields for strain D1v in single-substrate continuous culture were highest for sucrose and cellobiose and the maintenance energy coefficient for arabinose was at least 3.8-fold greater than for other substrates. We suggest that B. fibrisolvens may have evolved a mechanism to utilize certain sugars before arabinose in order to avoid this high maintenance energy expenditure.
Stress-Strain Behavior of Sands Cemented by Microbially Induced Calcite Precipitation

AbstractMicrobial induced calcite precipitation (MICP) is a novel biomediated ground improvement method that can be used to increase the shear strength and stiffness of soil. The evolution of the shear strength and stiffness of sand subjected to undrained and drained shearing is evaluated using triaxial tests. MICP treated sands with cementation levels ranging from young, uncemented sand to a highly cemented sandstonelike condition are subjected to undrained shear. A transition from strain hardening to strain softening behavior and a corresponding transition of global to localized failure as cementation is increased is observed. Moderately cemented specimens are subjected to various stress paths, which result in a change to the shear strength and volumetric behavior. Shear wave velocity is used to nondestructively monitor the change in small-strain stiffness during shearing, which provides an indication of cementation degradation as a function of strain level. Because shear wave velocity is influenced by ...
Increased cortical porosity in type 2 diabetic postmenopausal women with fragility fractures

The primary goal of this study was to assess peripheral bone microarchitecture and strength in postmenopausal women with type 2 diabetes with fragility fractures (DMFx) and to compare them with postmenopausal women with type 2 diabetics without fractures (DM). Secondary goals were to assess differences in nondiabetic postmenopausal women with fragility fractures (Fx) and nondiabetic postmenopausal women without fragility fractures (Co), and in DM and Co women. Eighty women (mean age 61.3 ± 5.7 years) were recruited into these four groups (DMFx, DM, Fx, and Co; n = 20 per group). Participants underwent dual-energy X-ray absorptiometry (DXA) and high-resolution peripheral quantitative computed tomography (HR-pQCT) of the ultradistal and distal radius and tibia. In the HR-pQCT images volumetric bone mineral density and cortical and trabecular structure measures, including cortical porosity, were calculated. Bone strength was estimated using micro–finite element analysis (µFEA). Differential strength estimates were obtained with and without open cortical pores. At the ultradistal and distal tibia, DMFx had greater intracortical pore volume (+52.6%, p = 0.009; +95.4%, p = 0.020), relative porosity (+58.1%, p = 0.005; +87.9%, p = 0.011) and endocortical bone surface (+10.9%, p = 0.031; +11.5%, p = 0.019) than DM. At the distal radius DMFx had 4.7-fold greater relative porosity (p < 0.0001) than DM. At the ultradistal radius, intracortical pore volume was significantly higher in DMFx than DM (+67.8%, p = 0.018). DMFx also displayed larger trabecular heterogeneity (ultradistal radius: +36.8%, p = 0.035), and lower total and cortical BMD (ultradistal tibia: −12.6%, p = 0.031; −6.8%, p = 0.011) than DM. DMFx exhibited significantly higher pore-related deficits in stiffness, failure load, and cortical load fraction at the ultradistal and distal tibia, and the distal radius than DM. Comparing nondiabetic Fx and Co, we only found a nonsignificant trend with increase in pore volume (+38.9%, p = 0.060) at the ultradistal radius. The results of our study suggest that severe deficits in cortical bone quality are responsible for fragility fractures in postmenopausal diabetic women. © 2013 American Society for Bone and Mineral Research
Three-Dimensional Quantitative Structure–Activity Relationships for Androgen Receptor Ligands

Comparative molecular field analysis (CoMFA), a three-dimensional quantitative structure-activity relationship (3D-QSAR) paradigm, was used to examine androgen receptor-binding affinities of a series of structurally diverse natural, synthetic, and environmental chemicals of interest. The CoMFA/3D-QSAR model successfully illustrates that the overall steric and electrostatic properties of structurally diverse ligands for the androgen receptor are necessary and sufficient to describe the binding affinity. The practical utility of models of this type is demonstrated using parent compounds in the training set and known as well as putative biological metabolites as test set molecules. The ability of the model to accurately predict binding affinity of test set molecules suggests that structure-based 3D-QSAR models may be used to supplement the process of hazard identification. The application of 3D-QSAR models within a toxicological framework is, at present, limited by the quantity and quality of biological data for relevant biomarkers of toxicity.
Discussion point: are web-based eCRFs a compliance problem for industry?

Pharmaceutical companies often rely upon web-based electronic Case Report Forms (eCRFs) for clinical investigators to enter trial data at their site. Using web-based technology means that the investigator directly enters data onto the sponsor company's server via the Internet. Does this cause a problem with complying with international standards regarding data integrity? Copyright © 2010 John Wiley & Sons, Ltd.
A cost‐utility analysis of treatment for acute childhood idiopathic thrombocytopenic purpura (ITP)

Background The primary objective in the treatment of acute pediatric idiopathic thrombocytopenic purpura (ITP) is to rapidly increase the platelet count. Methods We built a decision analytic model to evaluate the cost-utility of four commonly used treatment strategies: intravenous immunoglobulin G (IVIG) 0.8 g/kg, anti-D 75 mcg/kg, methylprednisolone (30 mg/kg for 3 days), and prednisone (4 mg/kg/day for 4 days). In our baseline model, all children were hospitalized upon presentation, and discharged once the platelet count reached ≥20,000. We performed a literature search to estimate time to platelet count ≥20,000 for each strategy, as well as the probability of side effects. We obtained cost data and quality of life measures from institutional and published data sources. Results Total cost of one-time treatment for a 20 kg child was $786 with prednisone, $1,346 with methylprednisolone, $2,035 with anti-D, and $2,492 with IVIG. The strategies of IVIG and methylprednisolone were less effective and more expensive than anti-D and prednisone, respectively. Although anti-D caused the most rapid rise in platelet counts, the incremental cost-utility ratio (costs incurred by using anti-D instead of prednisone divided by health benefit of using anti-D instead of prednisone) was $7,616 per day of severe thrombocytopenia avoided, primarily due to the much higher medication cost of anti-D. Utilizing an outpatient model, the cost difference between anti-D and prednisone was even more striking. Conclusions The clinical benefit of anti-D is offset by a substantial cost increase. Although often overlooked in favor of newer agents, a brief course of high-dose prednisone is an inexpensive and effective treatment for acute ITP. Pediatr Blood Cancer 2007;48:173–180. © 2006 Wiley-Liss, Inc.
Spectral evidence for weathered basalt as an alternative to andesite in the northern lowlands of Mars

Mineral abundances derived from the analysis of remotely sensed thermal emission data from Mars have been interpreted to indicate that the surface is composed of basalt (Surface Type 1) and andesite (Surface Type 2)1. The global distribution of these rock types is divided roughly along the planetary dichotomy which separates ancient, heavily cratered crust in the southern hemisphere (basalt) from younger lowland plains in the north (andesite)1. But the existence of such a large volume of andesite is difficult to reconcile with our present understanding of the geological evolution of Mars. Here we reinterpret martian surface rock lithologies using mineral abundances from previous work1 and new mineralogies derived from a spectral end-member set representing minerals common in unaltered and low-temperature aqueously altered basalts. Our results continue to indicate the dominance of unaltered basalt in the southern highlands, but reveal that the northern lowlands can be interpreted as weathered basalt as an alternative to andesite. The coincidence between locations of such altered basalt and a suggested northern ocean basin implies that lowland plains material may be composed of basalts weathered under submarine conditions or weathered basaltic sediments transported into this depocentre.
Clinical investigation of fenoterol, a new bronchodilator, in asthma.

Abstract In a randomized, double-blind, noncrossover study, 28 asthmatic patients received either ephedrine or fenoterol (Th1165a) a new β 2 -sympathomimetic bronchodilator, for 90 days. Forced expiratory flows and volumes and plethysmography were performed after a single test dose on days 1, 45, and 90. The subjects' clinical course was followed for patient acceptance and side effects. Compared to ephedrine, Th1165a was demonstrated to be a potent bronchodilator with a prolonged duration of action. Adrenergic side effects were minimal, and no tolerance or toxicity was demonstrated.
The tremble dance of the honey bee : message and meanings

The nectar foragers of a honey bee colony, upon return to the hive, sometimes perform a mysterious behavior called the tremble dance. In performing this dance, a forager shakes her body back and forth, at the same time rotating her body axis by about 50° every second or so, all the while walking slowly across the comb. During the course of a dance, which on average lasts 30 min, the bee travels about the broodnest portion of the hive. It is shown experimentally that a forager will reliably perform this dance if she visits a highly profitable nectar source but upon return to the hive experiences great difficulty finding a food-storer bee to take her nectar. This suggests that the message of the tremble dance is “I have visited a rich nectar source worthy of greater exploitation, but already we have more nectar coming into the hive than we can handle.” It is also shown experimentally that the performance of tremble dances is followed quickly by a rise in a colony's nectar processing capacity and (see Nieh, in press and Kirchner, submitted) by a drop in a colony's recruitment of additional bees to nectar sources. These findings suggest that the tremble dance has multiple meanings. For bees working inside the hive, its meaning is apparently “I should switch to the task of processing nectar,” while for bees working outside the hive (gathering nectar), its meaning is apparently “I should refrain from recruiting additional foragers to my nectar source.” Hence it appears that the tremble dance functions as a mechanism for keeping a colony's nectar processing rate matched with its nectar intake rate at times of greatly increased nectar influx. Evidently the tremble dance restores this match in part by stimulating a rise in the processing rate, and in part by inhibiting any further rise in the intake rate.
Analysis of Catfish Pricing and Market Dynamics: The Role of Imported Catfish

The producer price of catfish is becoming relatively unstable compared to the trend in previous years, necessitating the need for a complete analysis of catfish pricing and market dynamics. An understanding of the price determination mechanisms in the catfish market and the relationships between producer price, domestic processed price, and import price are important because price variability can result in significant financial losses to the domestic catfish industry. This study used a cointegration procedure to examine the long-run relationships between domestic prices of catfish and imported price. Results from unit root and cointegration tests suggest that there is a long-run equilibrium relationship between pairs of these prices. Results from Granger causality tests and error-correction model estimations suggest that the market for domestic frozen fillets plays a significant role in the price determination of imported catfish. A similar relationship is found between producer price and frozen fillet price. Some significant measures that were estimated include a frozen fillet-producer long-run price transmission elasticity of 0.162, a frozen fillet-imported fillet long-run price transmission elasticity of 3.56, and a producer-frozen fillet short-run price transmission elasticity of 0.322. High levels of fillet prices appear to have influenced the level of catfish imports. As long as distributors and restauranteurs do not see a basis for paying a premium for U.S. catfish products, they will continue to purchase the lower-priced imported catfish and consequently imports will continue to increase.
Analysis of the wet pressing of paper pulp

Abstract The equations governing the motion of the paper sheet in a press nip and the anisotropic percolation of the water in the sheet, are derived in invariant form. In order to avoid restrictive assumptions on the configuration of the paper sheet, the system of coordinates is generated by the flow of fibrous material through the nip region. With the corresponding constitutive equations, the formulation consists of a system of partial differential equations for the metric tensor of the coordinate system, and for the water velocity. For practical use, the solution is then mapped back into a cartesian frame of reference. Quantities of industrial interest, such as the residual water content and stresses, as well as the press-induced anisotropy, can be calculated in principle. A Galerkin finite-element approximation is implemented using rectangular linear elements. Two case studies are presented, for large and small permeabilities, and the corresponding differences in water pressure and velocity are in general qualitative agreement with the observations. Finally, the predictive value of the model is demonstrated by the dependence of the solution on the imposed shear stress and its gradient across the sheet.
Automatic VLAN creation based on on-line measurement

Virtual LANs (VLANs) permit hosts connected to a LAN switch to be grouped together into logical groups as a function of some management policy rather than simply of their physical location. Commercial LAN switches support a variety of policies based on either physical or logical addresses, protocol types, tagged frames, or user defined rules. The objective of these policies is the same: to reduce the amount of traffic that needs to be routed by grouping together hosts which are likely to communicate with each other into the same virtual LAN. This paper proposes a novel and more direct approach, it shows how VLANs can be created and removed dynamically as a function of the measured traffic patterns across the network. This is both simpler than configuring many static rules and permits the VLAN configuration to adapt to the evolution in the traffic patterns. The latter point is especially important in future LANs supporting peer-to-peer continuous media services, such as IP telephony or video-conferencing, in which clusters of hosts come together to communicate with each other intensively for relatively short periods of time and then form into new clusters.
Characterization of norepinephrine binding to plasma proteins of the dog and the rabbit.

Abstract The binding of 3 H-norepinephrine (L 3 HNE, 1.0 × 10 −9 M) to plasma proteins of the dog and the rabbit was studied under controlled conditions. Destruction of NE occured less rapidly at 22° than at 37°. Binding measured at 22° was equivalent to that at 37°, while binding measured at 0° was greater than that at 37°. Therefore, losses of plasma NE were minimized by incubation of samples at 22° for no longer than 30 minutes. L 3 HNE binding was examined in the absence and presence of 10 −9 to 10 −2 M non-labeled LNE, DL-NE, DL-normetanephrine (NM), DL-epinephrine (E), dopamine (DA), and catechol (C). Specific binding of L 3 HNE varied in the range of NE concentrations (L 3 HNE + non-labeled NE) from 10 −9 M (18.7 ± 3.1%, rabbit; 25.6 ± 4.8%, dog) to 10 −6 M (10.8 ± 3.1%, rabbit; 15.2 ± 3.6%, dog). Calculated binding constants (K D ) were consistent with binding to circulating proteins such as globulins or albumin (4.2 ± 1.2 × 10 −5 M, rabbit; 5.4 ± 1.7 × 10 −5 M, dog). In plasma from both species, non-labeled DL-NE, LNE, E, DA, and C, but not NM (from 10 −9 to 10 −2 M) each significantly displaced L 3 HNE from its binding site in a manner similar to displacement produced by non-labeled NE. The results demonstrate that 1) NE is bound to plasma proteins, although to a lesser extent than had been reported by other investigators; and 2) the binding of catecholamines to plasma proteins may be mediated by the catechol ring.
Isozymic uniformity in the presence of environmentally induced morphological variation in Apis mellifera capensis

Apis mellifera capensis Escholtz specimens from South Africa and Federal Republic of Germany exhibited identical electrophoretic patterns for malate dehydrogenase and nonspecific esterases. However, adults from Federal Republic of Germany (which were reared in cells of larger diameter) were significantly larger than workers from native populations in South Africa, and the same in three body measurements (body length, head capsule width, and length of forewing) as A. mellifera subspp. specimens from Laramie, Wyo. Certain environmental factors appear to have at least as much influence as genetic components in determining final body size of adult worker bees in A. m. capensis.
Wnt signalling in Caenorhabditis elegans: regulating repressors and polarizing the cytoskeleton.

Abstract Wnt proteins are secreted, cysteine-rich glycoprotein ligands with numerous roles during animal development. Recent studies of endoderm induction during embryogenesis in the nematode Caenorhabditis elegans challenge the prevailing view that Wnt signalling specifies cell fate by converting transcriptional repressors into activators. Instead, a mitogen-activated protein kinase (MAPK)-related pathway converges with Wnt signalling in C. elegans to relieve transcriptional repression. Furthermore, Wnt signalling induces endoderm in part by aligning the mitotic spindle in a responding cell along the anterior–posterior body axis. To orient mitotic spindles, Wnt signalling might directly target the cytoskeleton, prior to any regulation of gene transcription in responding cells.
Molecular pharmacology of aromatase and its regulation by endogenous and exogenous agents.

Abstract Aromatase (estrogen synthase) is the cytochrome P450 enzyme complex that converts C 19 androgens to C 18 estrogens. Aromatase activity has been demonstrated in breast tissue in vitro, and expression of aromatase is highest in or near breast tumor sites. Thus, local regulation of aromatase by both endogenous factors as well as exogenous medicinal agents will influence the levels of estrogen available for breast cancer growth. The prostaglandin E 2 (PGE 2 ) increases intracellular cAMP levels and stimulates estrogen biosynthesis, and our recent studies have shown a strong linear association between CYP19 expression and the sum of COX-1 and COX-2 expression in breast cancer specimens. PGE 2 can bind to four receptor subtypes, EP 1 –EP 4 , which are coupled to different intracellular signaling pathways. In primary human breast stromal cell cultures, aromatase activity was significantly induced by PGE 2 , dexamethasone, and agonists for the EP 1 and EP 2 receptor subtypes. An EP 1 antagonist, SC-19220, inhibited the induction of enzyme activity by PGE 2 or 17-phenyltrinor-PGE 2 , an EP 1 agonist. Sulprostone, an EP 3 agonist, did not alter aromatase activity levels. Investigations are also underway on the regulation of aromatase by exogenous medicinal agents. Selective steroidal and nonsteroidal agents are effective in inhibiting breast tissue aromatase. The benzopyranone ring system is a molecular scaffold of considerable interest, and this scaffold is found in certain flavonoid natural products that have weak aromatase inhibitory activity. Our novel synthetic route for benzopyranones utilizes readily available salicylic acids and terminal alkynes as starting materials. The synthesis of flavones with diversity on the benzopyranone moiety and at the C-2 position occurs with good to excellent yields using these reaction conditions, resulting in an initial benzopyranone library of thirty compounds exhibiting enhanced and differential aromatase inhibition. Current medicinal chemistry efforts focus on diversifying the benzopyranone scaffold and utilizing combinatorial chemistry approaches to construct small benzopyranone libraries as potential aromatase inhibitors.
Component-Mode Reduced-Order Models for Geometric Mistuning of Integrally Bladed Rotors

Two methods that explicitly model airfoil geometry surface deviations for mistuning prediction in integrally bladed rotors are developed by performing a modal analysis on different degrees of freedom of a parent reduced-order model. The parent reduced-order model is formulated with Craig–Bampton component-mode synthesis in cyclic symmetry coordinates for an integrally bladed rotor with a tuned disk and airfoil geometric deviations. The first method performs an eigenanalysis on the constraint-mode degrees of freedom that provides a truncated set of interface modes, whereas the second method includes the disk fixed-interface normal mode in the eigenanalysis to yield a truncated set of ancillary modes. Both methods can use tuned or mistuned modes, where the tuned modes have the computational benefit of being computed in cyclic symmetry coordinates. Furthermore, the tuned modes only need to be calculated once, which offers significant computational savings for subsequent mistuning studies. Each geometric mist...
NO control: nitric oxide directly regulates substrate delivery to NOS. Focus on “Nitric oxide can acutely modulate its biosynthesis through a negative feedback mechanism on l-arginine transport in cardiac myocytes”

although the amino acid arginine is commonly associated with nitric oxide (NO) production via NO synthase (NOS), it also participates in the synthesis of urea, creatine, creatinine, agmatine, polyamines, as well as overall protein synthesis. Furthermore, it also influences hormone release (insulin,
The 1994 violent crime control and law enforcement act: An evaluation

August 1994 saw the passage of the Crime Control Bill in Congress. There was much criticism regarding such a bill. The Republicans were opposed to all crime prevention programs which did not look to emphasize stiffer prison sentences for the accused. This paper is an analysis of this bill and takes into consideration the history of the “Crime Control” model as developed by Herbert Packer. How does one control crime, and should we not emphasize more crime control strategy than ever before?
Fertility in patients with genetic deficiencies of cytochrome P450c17 (CYP17A1): combined 17-hydroxylase/17,20-lyase deficiency and isolated 17,20-lyase deficiency

CYP17A1 catalyzes the 17-hydroxylase and 17,20-lyase reactions, regulating the steroid hormones produced by the adrenal glands and gonads. Mutations that compromise all CYP17A1 activities are extremely rare and cause combined 17-hydroxylase/17,20-lyase deficiency. Clinically, combined 17-hydroxylase/17,20-lyase deficiency presents with hypertension, hypokalemia, primary amenorrhea, and sexual infantilism. A few mutations selectively impair 17,20-lyase activity, and some mutations in cofactor proteins cytochrome P450-oxidoreductase and cytochrome b5 also selectively disrupt 17,20-lyase activity. The defect in sex steroid synthesis impairs fertility in both male and female patients when the deficiency is severe. This paper reviews the genetics, steroidogenesis, and fertility impairments associated with these disorders.
Racial stereotyping and medicine: the need for cultural competence

In almost every nation in the world, increased burdens of morbidity and mortality afflict racial and ethnic minorities and new immigrant populations. In the United States, inferior health status has been documented for African-Americans, people of Hispanic origin, American Indians and some groups of