cssi/SciSciGPT-SciSciNet huggingface dataset:
The cattle are eating the forest

Honduras, a poor country, imports food while its fertile land is converted to pasture. What are the human and ecological consequences tor Honduras and other developing countries of this shift in land use?
Fast reactions with nano- and micrometer aluminum: A study on oxidation versus fluorination

Abstract The use of fluorine as an oxidizing agent in aluminum (Al)-based thermite reactions yields higher peak pressures and an increase in gas production compared with oxygen-containing oxidizers, such as molybdenum trioxide (MoO 3 ). Thus fluorination reactions have the potential to excel in situations that require high pressures and flame speeds. This study compares the combustion behaviors of Al/Teflon, Al/MoO 3 /Teflon, and Al/MoO 3 in an effort to determine the effects that the replacement of oxygen with fluorine has on the reaction dynamics in both open and confined burning configurations. Data were collected from pressure sensors and high-speed imaging. The mass percent of Al was varied from 10 to 90% to study the effects of composition. The composites were then further tested at the optimum stoichiometry using either 50 nm or 1–3 μm Al to examine the effect of Al particle size. The addition of Teflon in an open configuration hinders the reaction due to a loss of liberated gas. Confining the reaction enables the trapped gases to enhance convection, yielding increased flame speeds. For confined conditions, the reactions containing Teflon exhibit higher peak pressures but lower flame speeds than the reactions with MoO 3 . These results imply that a direct relationship between generated gas pressures and flame speeds does not generally exist when comparing different oxidizers. The theoretically predicted relationship for the relative flame speed versus relative particle size based on the melt-dispersion mechanism agrees with experimental data for all Al particle sizes and for the fluorination reaction. Particle synthesis parameters are suggested that could be controlled to enable micrometer-scale Al particles to achieve the performance of nanoscale Al particles. This is of significant practical importance, because nanoparticles are 30 to 50 times more expensive than the micrometer particles.
A generative model of working set dynamics

An algorithm for generating a page reference string which exhibits a given working set size behavior in the time domain is presented, and the possible applications of such a string are discussed. The correctness of the algorithm is proved, and its computational complexity found to be linear in the length of the string. A program implementing the algorithm, which is performed in one pass and requires very little space, is briefly described, and some experimental results are given.
Therapeutic innovation: ethical boundaries in the initial clinical trials of new drugs and surgical procedures.

This issue of Daedalus and the conferences from which it sprang seem to have been initiated by widespread concern over the pre cise details and clinical practices of human experimentation in bio medical research. By "human experimentation'' was meant either the intentional employment of normal human subjects as volunteers for physiologic experiments, or the study of patients (in a way that would not directly benefit them) to gather information on a disease or its treatment. While both of these ethical problems are worthy of consideration, they do not appear to me to present any severe on going ethical or technical difficulty in American medicine today. There are far more severe ethical problems in the Armed Forces, where chemical and biological warfare systems are studied on nor mal human volunteers who suffer the coercion intrinsic in military activity, or in the Space Program with its high lethality-potential in failed missions.
Laser-generated ultrasonic characterization of irradiated glass optical fibers

Abstract Glass optical fibers were irradiated from 100 krad (Si) to 1 Mrad (Si) with gamma radiation from a cobalt-60 source. The irradiated fibers were characterized with laser-generated ultrasonics as well as electron spin resonance techniques. Phosphorus- and germanium-based color centers were observed in the exposed fibers, and the intensity of the color centers was found to increase as the fibers were exposed to larger radiation doses. The extensional wave speed was found to decrease with increasing radiation exposure owing to elastic softening of the fiber. A linear relationship was inferred between the electron spin resonance intensity and the extensional wave speed.
Ozone-induced cell death occurs via two distinct mechanisms in Arabidopsis: the role of salicylic acid.

Summary Previous studies suggest that salicylic acid (SA) plays an important role in influencing plant resistance to ozone (O3). To further define the role of SA in O3-induced responses, we compared the responses of twoArabidopsisgenotypes that accumulate different amounts of SA in response to O3 and a SA-deficient transgenic Col-0 line expressing salicylate hydroxylase (NahG). The differences observed in O3-induced changes in SA levels, the accumulation of active oxygen species, defense gene expression, and the kinetics and severity of lesion formation indicate that SA influences O3 tolerance via two distinct mechanisms. Detailed analyses indicated that features associated with a hypersensitive response (HR) were significantly greater in O3-exposed Cvi-0 than in Col-0, and that NahG plants failed to exhibit these HR-like responses. Furthermore, O3-induced antioxidant defenses, including the redox state of glutathione, were greatly reduced in NahG plants compared to Col-0 and Cvi-0. This suggests that O3-induced cell death in NahG plants is due to the loss of SA-mediated potentiation of antioxidant defenses, while O3-induced cell death in Cvi-0 is due to activation of a HR. This hypothesis is supported by the observation that inhibition of NADPH-oxidases reduced O3-induced H2O2 levels and the O3-induced cell death in Cvi-0, while no major changes were observed in NahG plants. We conclude that although SA is required to maintain the cellular redox state and potentiate defense responses in O3 exposed plants, high levels of SA also potentiate activation of an oxidative burst and a cell death pathway that results in apparent O3 sensitivity.
Transient Method for Convective Heat Transfer Measurement With Lateral Conduction—Part I: Application to a Deposit-Roughened Gas Turbine Surface

The effect of lateral conduction on convective heat transfer measurements using a transient infrared technique over a rough surface is evaluated. The rough surface is a scaled model of gas turbine surface deposits. Comparisons are made between a full 3D finite volume analysis and a simpler ID transient conduction model. The surface temperature history was measured with a high resolution infrared camera during an impulsively started hot gas flow over the rough test plate at a flow Reynolds number of 750,000. The boundary layer was turbulent with the peak roughness elements protruding just above the boundary layer momentum thickness. The ID model underestimates the peak to valley variations in surface heat flux by up to a factor of 5 compared with the 3D model with lateral conduction. For the area-averaged surface heat flux, the ID model predicts higher values than a 3D model for the same surface temperature history. This is due to the larger surface area of the roughness peaks and valleys in the 3D model, which produces a larger initial input of energy at the beginning of the transient. For engineering purposes, where the net heat load into the solid is desired, this lower 3D model result must be multiplied by the wetted-to-planform surface area ratio of the roughness panel. For the roughness model in this study, applying this correction results in a 25% increase in the area-averaged roughness-induced Stanton number augmentation for the 3D rough surface model compared with a flat ID surface model at the same Reynolds number. Other shortcomings of the transient method for rough surface convective heat transfer measurement are identified.
Simple Method to Eliminate Interference between Ventricular Assist Devices and Cardiac Rhythm Devices

Background: Report on a simple solution to allow programming of defibrillators in the presence of a Heartmate II (Thoratec Corporation, Pleasanton, CA, USA) ventricular assist device. Ventricular assist devices have become increasingly utilized for patients waiting for heart transplantation as well as those who will be maintained on a permanent support. The Heartmate II, which was recently given Food and Drug Administration approval as a bridge-to-transplant device, has a particular anomaly that complicates patient management. The pulse width modulator of the Heartmate II produces electromagnetic noise that interferes with the ability to interrogate and program certain defibrillators, and explantation of the defibrillator has been reported as the only viable solution. Methods: The authors describe the use of cast-iron pans to reduce the electromagnetic interference between St. Jude Medical's first-generation Atlas family of defibrillators (St. Jude Medical, St. Paul, MN, USA) and the Heartmate II pump. Results: The use of a simple shielding protocol avoids the need to remove a pre-existing defibrillator from a patient receiving support from the Heartmate II ventricular assist device. Conclusions: The method described herein is important as future generations of medical devices may present different types of device-device interactions. Simple bedside methods to eliminate interference can potentially help patients who would otherwise need one or another device removed
Studies on the action of insulin in isolates adipose tissue cells II. 3′,5′-nucleotide phosphodiesterase and antilipolysis

Abstract 1. 1. In isolated fat cells the inhibition of lypolysis by insulin in the presence of ACTH, glucagon and epinephrine occured in a similar concentration range of insulin and exhibited noncompetitive characteristics. In contrast, the antagonism to caffeine was competitive. 2. 2. Ado-3′,5′- P caused lipolysis in fat cells incubated in a Tris-bicarbonate-albumin medium. Lipolysis induced by either Ado-3′,5′- P or by its dibutyryl derivative could not be blocked by insulin, indicating that the hormone neither interfered with lipase activation nor activated phosphodiesterase. 3. 3. 10 mM of imidazole lowered lipolysis stimulated by epinephrine and lipolysis from Ado-3′,5′- P but had no significant effect on lipolysis stimulated by N 6 , O 2 -di-butyryl-Ado-3′,5′- P . 4. 4. The greater part of the phosphodiesterase activity in the fat cell was found in the 700 × g sediment. When this fraction was subjected to ultrasonication or to mechanical homogenization, the enzyme activity was released and remained in the 100 000 × g supernatant. A pH optimum was found in the region of 7.0–7.5 with a K m =0.5 mM, a dependency on Mg 2+ and a preference for cyclic nucleotides with a purine base, similar to the rat liver enzyme. 5. 5. While inhibition of phosphodiesterase activity by theophylline and stimulation by cacodylate and imidazole were readily demonstrated, no stimulation by nicotinic acid or by insulin could be obtained when the compounds were added directly to the test mixture. A previous incubation of fat cells with insulin or nicotinic acid did not result in phosphodiesterase activation in homogenates. The data do not support the concept that insulin or nicotinic acid may act through the activation of phosphodiesterase.
Attentional retraining administered in the field reduces smokers' attentional bias and craving.

Objective Attentional retraining (AR) is a potential new treatment for addiction. AR trains addicts to attend away from drug-related cues, thereby reducing exposure to drug cues and reducing craving. We examined the utility of delivering AR to smokers on a personal digital assistant (PDA) in the natural environment. Method Smokers (N = 60) not seeking to quit were randomly assigned to an AR group or a control group (i.e., a group with no training). They carried a PDA with them for one week. They were prompted to complete four assessments daily, including three attentional retrainings (AR group) or three control trainings (control group), and one evaluation of attentional bias. AR was implemented using a modified visual probe task. Attentional bias was assessed using a standard visual probe task on the PDA. Results The AR group completed an average of 15.0 attentional retrainings and the control group completed an average of 14.9 control trainings. As hypothesized, attentional bias declined over the week in the AR group, but not in the control group, Group × Day interaction, F(1, 232) = 4.77, p = .03. AR also reduced craving ratings following a briefly presented picture containing smoking and nonsmoking features, group main effect, F(1, 234) = 3.89, p = .04. AR did not significantly influence smoking behavior. Conclusion AR can be administered on a mobile device in the natural environment, and AR can reduce attentional bias and craving.
Transfer records for transmitting casts to the laboratory

Accurate cast relationships are necessary to send a cast to the laboratory when transfer records are used. The technique described eliminates errors which might develop when unstable materials are used for record making and cast relating. The disadvantage is increased laboratory time. Approximately 45 minutes are required to fabricate each record.
Computer-aided design

This project is engaged in (a) a program of research into the application of the concepts and techniques of modern data processing to the design of mechanical parts, and (b) the further development of automatic programming systems for numerically controlled machine tools. The project is a cooperative venture between the Computer Applications Group of the Electronic Systems Laboratory and the Design and Graphics Division of the Mechanical Engineering Department, and is sponsored by the Manufacturing Methods Division of the USAF Air Material Command through Contract AF-33(600)-40604.
The reproducibility of luteinizing hormone surges following agonist trigger: analysis of 1792 agonist triggers

WITHDRAWN O-354 Wednesday, October 22, 2014 05:15 PM EGGDONORANEUPLOIDY RATES SIGNIFICANTLYDIFFER BETWEEN FERTILITY CENTERS. S. Munne, M. Alikani, J. Barritt, J. Hesla, B. Kaplan, M. Alper, D. McCulloh. Reprogenetics, Livingston, NJ; The Center for Human Reproduction, North Shore University Hospital, Manhasset, NY; ART Reproductive Center and Southern California Reproductive Center, Beverly Hills, CA; Oregon Reproductive Medicine, Portland, OR; Fertility Centers of Illinois, Highland Park, IL; Boston IVF, Waltham, MA; New York University Fertility Center, New York, NY. OBJECTIVE: To investigate if aneuploidy rates differ between fertility centers. Aneuploidy rates could differ due to differences in population age and infertility indication. However, any differences in aneuploidy rates between egg donor cycles are probably induced by differences in center-specific treatments. DESIGN: Aneuploidy rates in blastocysts from egg donation cycles from different fertility centers were compared. MATERIALS ANDMETHODS: 616 Egg donor cycles (average age 25.8 years) underwent blastocyst biopsy for PGS at 20 fertility centers. Biopsied samples were analyzed at the same reference laboratory by array CGH. Ploidy data were examined using multiple logistic regression considering the mean incidence of euploidy per patient to see whether euploidy rates differed among centers. Each facility was compared against the mean incidence of euploidy for all facilities. RESULTS: Different centers had significantly different incidences of euploidy and these were independent of the number of biopsied embryos and donor age. Euploidy rates significantly deviated from the average of 65% (0.65 0.01) in 7 of the 20 centers included, ranging from 42% to 80%. Four centers had significantly lower euploidy rates (0.42 0.10, 0.47 0.07, 0.51 0.03, 0.51 0.07) and 3 significantly higher (0.77 0.02, 0.79 0.03, 0.80 0.02).
Predicted gain and functional gain with transcranial routing of signal completely-in-the-canal hearing aids.

Transcranial routing of signal (TCROS) was accomplished using completely-in-the-canal (CIC) hearing aids in 5 profoundly unilaterally hearing-impaired individuals. The functional gain realized by t...
Drug Crops and Food Security: The Effects of Khat on Lives and Livelihoods in Northern Madagascar

Khat is a bushy plant whose leaves are chewed for their stimulant effect. Although khat has been a boon to the local economy, a suspected disadvantage is that there has been a decrease of land dedicated to rice and vegetable crops. Concerns about khat stem from genuine issues of food security but also from a moral panic targeted at this recreational drug crop. The major finding is that a decrease in vegetable production has not been primarily caused by khat but instead by a decline in the market for vegetables and decayed local infrastructure supporting vegetable production and transport. We also found that most farmers prefer to grow food crops alongside their khat, and many grow khat on marginal lands. Furthermore, khat helps many individual farmers increase food security because of the income it provides. The general significance is to point out that drug crops have a unique place in discussions of food security because of both the high amount that buyers are willing to pay and because of public condemnation of recreational drugs.
Influence of engineered titania nanotubular surfaces on bone cells.

A goal of current orthopedic biomaterials research is to design implants that induce controlled, guided, and rapid healing. In addition to acceleration of normal wound healing phenomena, these implants should result in the formation of a characteristic interfacial layer with adequate biomechanical properties. To achieve these goals, however, a better understanding of events at the bone–material interface is needed, as well as the development of new materials and approaches that promote osseointegration. Using anodization, titania interfaces can be fabricated with controlled nanoarchitecture. This study demonstrates the ability of these surfaces to promote osteoblast differentiation and matrix production, and enhance short- and long-term osseointegration in vitro. Titania nanotubular surfaces were fabricated using an anodization technique. Marrow stromal cells (MSCs) were isolated from male Lewis rats and seeded on these surfaces along with control surfaces. The interaction of cells with these surfaces was investigated in terms of their ability to adhere, proliferate and differentiate on them. The experiments were repeated three times with cells from different cultures. All the results were analyzed using analysis of variance (ANOVA). Statistical significance was considered at p<0.05. Furthermore, in vivo biocompatibility was assessed by implanting surfaces subcutaneously in male Lewis rat and performing histological analysis after 4 weeks. Our results indicate that the nanotubular titania surfaces provide a favorable template for the growth and maintainence of bone cells. The cells cultured on nanotubular surfaces showed higher adhesion, proliferation, ALP activity and bone matrix deposition compared to those grown on flat titanium surfaces. In vivo biocompatibility results suggest that nanotubular titania does not cause chronic inflammation or fibrosis. The fabrication routes of titania nano-architectures are flexible and cost-effective, enabling realization of desired platform topologies on existing non-planar orthopedic implants.
Sex-linked heritability of a sexually selected character in a natural population of Poecilia reticulata (Pisces: Poeciliidae) (guppies)

The relative extent of orange-pigmented spots in the colour patterns of male guppies, Poecilia reticulata, has previously been shown to be a basis for female choice. Parent–offspring and half-sib breeding experiments and selection experiments were conducted to determine if heritability of this character is maintained in the face of apparent sexual selection. The results demonstrate strong heritability of orange area. High father–son regression slopes, strong response to selection and a relatively small dam component of variance indicate that this character has Y-linked inheritance. This result for a quantitative character is in agreement with earlier work showing Y-linked inheritance of particular colour pattern elements in guppies. The high heritability of orange area suggests that this trait is probably not an indicator of fitness variation as postulated by some ‘good genes’ models for the evolution of female mate choice but that it does have the potential for further evolutionary change and elaboration.
Crystallographic studies on B12 binding proteins in eukaryotes and prokaryotes

The X-ray crystal structures of several important vitamin B12 binding proteins that have been solved in recent years have enhanced our current understanding in the vitamin B12 field. These structurally diverse groups of B12 binding proteins perform various important biological activities, both by transporting B12 as well as catalyzing various biological reactions. An in-depth comparative analysis of these structures was carried out using PDB coordinates of a carefully chosen database of B12 binding proteins to correlate the overall folding of the molecule with phylogeny, the B12 interactions, and with their biological function. The structures of these proteins are discussed in the context of this comparative analysis.
Independent pathways for water and solute movement across the cell membrane.

In published studies of the relationship between movement of nonelectrolytes across cell membranes and the lipid solubility of these test molecules, it is generally found that a number of the smaller, more water-soluble molecules deviate significantly from the general pattern relating permeability (or reflection coefficient) to lipid solubility. This is often true of the amides, for example, whose reflection coefficients are considerably lower than expected on the basis of lipid solubility. While this has been interpretep in terms of the movement of these solutes through aqueous channels in the membrane, it now appears that many of these “deviant” molecules may cross the membrane by means of carrier-mediated diffusion, independent of osmotic water flow. This has important implications for studies in which equivalent pore radius has been estimated from the reflection coefficients of small hydrophilic molecules, and for our present concepts of membrane structure.
American Indian Farm Planning: An Analytical Approach to Tribal Decision Making

A multiyear linear programming model is used to assist an American Indian tribe develop agricultural plans for its tribal farm. Five-year crop, livestock, and investment plans are generated consistent with the tribal resource base, goals, and decision-making structure. The model has influenced the tribal farm decision-making process and provided the primary farming guide for 1979 and 1980. Frequent communication with the tribe was crucial in developing the model. Adequate updating procedures will be important in future farm planning. 13 references.
Planetary science: shades of Titan.

Instruments aboard the Cassini spacecraft can ‘see’ through the dense atmosphere of Titan, Saturn's largest moon. Returned images hint at the existence of features such as ridges and valleys, and perhaps an icy volcano. The surface of Saturn's largest moon, Titan, is coated in a dense methane-rich atmosphere that prevents high-resolution imaging at visible wavelengths. During its first Titan flyby last October, the Cassini spacecraft's visual and infrared mapping spectrometer (VIMS) was able to reveal detailed surface structures, as reported in this issue. Notable features include a circular structure 30 km in diameter, thought to be a cryogenic dome. This may be volcanic, which could explain how the methane in Titan's atmosphere is replenished.
Influence of oxygen partial pressure on optoelectrical properties of aluminum-doped CdO thin films

Abstract Highly conducting and transparent aluminum-doped CdO thin films were deposited on quartz by ablating the sintered target of CdO containing 2 wt% of aluminum with a KrF excimer laser (λ = 248 nm and pulsed duration of 20 ns). The effect of oxygen partial pressure on structural, electrical, and optical properties was studied. It is observed that the (2 0 0) plane is highly preferred for the films grown under high oxygen pressure. The conductivity, carrier concentration and mobility of the films decrease with increase in the oxygen pressure after attaining maximum. Low resistivity (2.27 × 10−5 Ω cm), and high mobility (79 cm2 V−1 s−1) is observed for the film grown under oxygen pressure of 1.0 × 10−3 mbar. The optical band gap is found varying between 2.68 and 2.90 eV for various oxygen pressure.
A Cost Function Analysis of Import Demand and Growth in South Africa

Abstract This study investigates the substitutability relationships among capital, labor, and imported inputs for South Africa, utilizing the estimates obtained from an aggregate cost function. Our results are consistent with the hypothesis that capital is a substitute for both domestic labor and imports, but that labor and imports are complementary inputs. This latter result suggests that relaxing South African trade restrictions may have a positive impact, in both the long and the short run, on the demand for domestic labor. Other results suggest that the reduction of market impediments may also positively impact the production of investment goods and economic growth.
URINARY EXCRETION BY MAN OF 11β,17α,20α, 21-TETRAHYDROXY-4-PREGNEN-3-ONE AND THE 20β EPIMER

Reduction of the C-20 ketonic group to the 20α hydroxy and 20β epimer appears to be one of the major metabolic pathways of steroid metabolism in man. This study reports the identification of 11β,17α,20α,21-tetrahydroxy-4-pregnen-3-one and the 20β epimer isolated from extracts of the urine 1) from a man receiving adrenocorticotropin, 2) from a woman with hypopituitarism, after she had ingested 400 mg. of cortisol acetate, 3) from 3 “normal” men (a “pool”), and 4) from a normal man. These results confirm the findings of Peterson, Pieree and Kliman after administration of cortisol to normal men, and of Holness, Lunnon and Gray who found the 20β epimer after the administration of adrenocorticotropin. In addition this study reports the findings of the 20β epimers after administration of adrenocorticotropin, and both epimers in urine from normal men.
Memory for central and peripheral actions and props after varied post-event presentation

Purpose. The effects of varying post-event information (information was unchanged from the original event, misleading or added an incorrect detail) on memory for central and peripheral actions and props in a crime scene were examined. Methods. After pre-testing 105 undergraduates to obtain centrality ratings for target items (actions and props), 300 additional undergraduates were presented with slides of a crime followed by a narrative in which one target item was unchanged from the original presentation, one was changed (misleading), and one had an incorrect detail added. Participants were tested using one of four memory tests: item recognition, source recognition, cued recall or sentence completion (an indirect memory test). Results. Misinformation effects were found for all four dependent measures. People were more resistant to misleading central than peripheral information, and readily accepted incorrect added details in recognition tests, but rarely generated them in recall or sentence completion. Conclusions. Two major conclusions can be drawn. Peripheral items are more strongly influenced by misleading information than are central items, and those who provide a free account of what they witness are unlikely to include details, but may accept incorrect details when questioned. Implications for eyewitness testimony and future research in eyewitness memory are discussed.
Calibration-based models for correction of area estimates derived from coarse resolution land-cover data

Calibration-based area correction models provide improved estimates of cover-type proportions measured at coarse scales. Three separate regions (Plumas and Stanislaus National Forests and Lake Tahoe Basin) in the northern Sierra Nevada serve as test sites: the first for model calibration and the others for extrapolation and validation of the area correction methods. The use of one (or a few) large sites to calibrate models for extrapolative application over large areas represents a global test-site sampling strategy that most easily can be employed for the development of global land cover and land-cover change products. The inverse estimator, calibrated on scale-specific interclass transition matrices, produces the best overall results at the coarser scales for both validation sites. Good results probably occur because the conditional probabilities in the transition matrices implicitly carry information about the spatial organization of the landscape. This method performs poorly at finer scales, or in cases where the calibration and validation sites have dissimilar spatial organization, or class confusions. The slope estimator, calibrated on the coefficients of scale-specific proportion transition lines, produces improved estimates over uncorrected values at all scales. The slope estimator appears to generalize most successfully because it characterizes the basic tendency of small classes to diminish and large classes to increase in size as the landscape is represented at increasingly coarser scales. The positive results achieved using the inverse estimator and the slope estimator indicate potential for using such a posteriori calibration methods to improve coarse resolution land-cover area estimates over large regions.
Impact Factors and Emergency Medicine Journals

Abstract See related articles Fontanarosa PB: Impact factors and emergency medicine journals. Ann Emerg Med January 1998;31:107-109.]
Citric acid as the test meal for the 13C-urea breath test.

Abstract OBJECTIVE: Test meals are used in the urea breath test to slow gastric emptying and to increase the area of contact with the substrate. Recently, citric acid has been suggested as an improved liquid test meal. The mechanism is unknown and could act by delaying gastric emptying, decreasing the pH at the site of the bacteria, or both. Our aim was to evaluate the effects of citric acid test meals on urea hydrolysis in vivo, to identify the possible mechanism for enhanced urea hydrolysis, and to identify the minimum effective dose. METHODS: We compared the U.S. commercial 13C-urea breath test with four liquid test meals (200 ml of water) consisting of citric acid, ascorbic acid, sodium citrate, and glucose polymer and also after the subcutaneous administration of pentagastrin. We studied healthy volunteers with and without proven H. pylori infection (by serology and histology). 13C-urea was administered orally simultaneously with the liquid test meals or immediately after the pudding had been ingested. Breath samples were taken before and after oral administration of the 13C-urea. RESULTS: A dose response in urease activity was evident as the amount of citric acid was increased from 1 to 4 g. Citric acid at 1, 2, or 4 g produced significant increases in breath 13CO2 activity, compared with the commercial pudding (p CONCLUSIONS: The data are consistent with the marked effect of citric acid on gastric emptying and, possibly, distribution of the urea within the stomach being largely responsible for the enhanced urease activity with citric acid test meals. It should be possible to use a low dose of citric acid (e.g., 1 g per 200 ml) to enhance the simplicity and palatability of the test.
Effect of Aging on the Cardiothoracic Ratio of Men

The potential usefulness of chest radiographs in the assessment of physical dimensions was examined in 243 men (age range 20-95 years) who had been followed up for an average of 12.3 years. From 1,124 of these films, measurements of cardiac diameter (CD) and thoracic diameter (TD) were made, and the cardiothoracic ratio (CTR) was calculated. Cross-sectional age differences were associated with a tendency toward increases in the CD and CTR throughout the lifespans of the 243 men, regardless of the presence or absence of heart disease. The thoracic diameter (TD) was greater in middle-aged than in young subjects, but less in the oldest than in the middle-aged subjects. Cumulative percentage curves for the CTR showed a shift to higher fiftieth to ninetieth percentile values with age. However, among the subjects free of heart disease, only one (age 95) had a CTR exceeding 50 per cent. Longitudinal analysis data agreed with the cross-sectional data. Forty-nine deceased subjects were matched with living subjects of the same heart disease classifications. Increases in the CD and CTR were predictive of death in the group with heart disease but not in the group without identifiable heart disease. An increase in CD was not correlated with an increase in systolic blood pressure. The decline in TD appeared to reflect a decline in rib-cage mobility with aging.
Effect of diurnal sampling on the headspace composition of detached Nicotiana suaveolens flowers

Abstract Compounds emitted over a 24 hour sampling period by detached flowers of Nicotiana suaveolens were examined after collecting flowers at 12:00 and 24
X-ray photoelectron spectroscopy study of the interface between aluminum and spin-coated polyamic acid

The interfacial properties between pyromellitic dianhydride-oxydianiline (PMDA-ODA) and aluminum substrate have been studied by X-ray photoelectron spectroscopy. The spin-coating method was used to obtain ultra-thin films required to characterize the interface between the substrates and organic films. Adhesion between the substrate and the polyimide was accomplished by baking for about 5 h at 240°C without the use of an adhesion promoter.
The effect of bubble column diameter on gas holdup in fiber suspensions

Abstract Three bubble column diameters ( D = 10.2 , 15.2, and 32.1 cm) are employed to study the scale-up effect on gas holdup in air–water and air–water–cellulose fiber (hardwood, softwood, and BCTMP) systems. The effect of column diameter depends on flow regime and fiber mass fraction. When D ⩽ 15.2 cm , gas holdup decreases with increasing column diameter for the transitional and heterogeneous flow regime, and column diameter effects are negligible in the homogeneous flow regime. When D ⩾ 15.2 cm , gas holdup is only affected by column diameter in the transitional flow regime for an air–water system and low fiber mass fraction suspensions ( C ⩽ 0.25 % ); column diameter effects disappear at medium fiber mass fractions (e.g., C = 0.8 % ) but are significant at high fiber mass fractions (e.g., C = 1.4 % ).
Chromatographic separation of activated and unactivated forms of aldose reductase.

Abstract Chromatography of bovine kidney aldose reductase using Matrex Orange A affinity gel results in the separation of the unactivated and activated enzyme forms. The former washes through the column, while the latter is eluted with an NADPH step-gradient. The separated enzyme forms display Vmax and Km glycolaldehyde values, and relative sensitivities to inhibition by the aldose reductase inhibitor AL-1576 (spiro[2,7-difluorofluorene-9, 4′-imidazolidine]-2′,5′-dione), that are similar to those reported previously for the individual forms. However, because Vmax is 17-fold lower for the unactivated enzyme, the purification of aldose reductase via NADP(H) elution from a dye-ligand affinity matrix can result in the selective purification of only the activated enzyme form. These results have direct implications for the study of potential aldose reductase inhibitors, and may explain why linear double-reciprocal plots are commonly observed for enzyme prepared in this manner, while nonlinear plots are seen in other cases.
Aortic endograft infection due to Pasteurella multocida following a rabbit bite

Abdominal aortic endograft infection is a serious complication after an endovascular abdominal aortic aneurysm repair. Pasteurella multocida, a gram-negative bacterium, is a commonly found organism in the mouth flora of many house pets. We report a case of an aortic endograft infection caused by P multocida after a rabbit bite. Successful treatment was performed by extra-anatomic revascularization followed by endograft removal.
A Time-Domain Dynamic Model for Chatter Prediction of Cylindrical Plunge Grinding Processes

This paper presents a time-domain dynamic model, which simulates cylindrical plunge grinding processes under general grinding conditions. The model focuses on the prediction of grinding chatter boundaries and growth rates. Critical issues are considered in the model including: the distributed nonlinear force along the contact length, the geometrical interaction between the wheel and workpiece based on their surface profiles, the structure dynamics with multiple degrees of freedom for both the wheel and workpiece, the response delay due to spindle nonlinearities and other effects, and the effect of the motion perpendicular to the normal direction. A simulation program has been developed using the model to predict regenerative forces, dynamic responses, surface profiles, stability regions, and chatter growth rates. The model is validated using existing numerical and experimental results.
Temporal variation of cloud fraction : effects on a simulated sea-ice cover

The Arctic sea-ice cover is typically simulated using monthly-mean cloud fractions. To examine the sensitivity of sea-ice thickness and distribution to the more realistic case of cloud fractions that vary over synoptic time scales, we simulate the ice cover with a two-dimensional ice model and simple radiation parameterizations containing linear and non-linear cloudiness terms. Using a common non-linear parameterization with daily-varying, clear-sky/overcast cloud fractions that sum to the monthly mean rather than daily cloud fractions equal to the monthly mean, the simulated ice volume in the Arctic and peripheral seas increases by 38% overall with a net decrease in downwelling shortwave radiation of 26%. Mid-summer ice extent increases by 17%, while ice thickness doubles in the Kara and Barents seas. Since the ice model is shown to respond nearly linearly to day-to-day variations in downwelling radiation, the need to consider synoptic variability of cloud fraction depends on the non-linearity of the relationship between cloud fraction and radiation.
Void fraction and flow regime in adiabatic upward two-phase flow in large diameter vertical pipes

In pipes with very large diameters, slug bubbles cannot exist. For this reason, the characteristics of two-phase flow in large pipes are much different than those in small pipes. Knowledge of these characteristics is essential for the prediction of the flow in new nuclear reactor designs which include a large chimney to promote natural circulation. Two of the key parameters in the prediction of the flow are the void fraction and flow regime. Void fraction measurements were made in a vertical tube with diameter of 0.15 m and length of 4.4 m. Superficial gas and liquid velocities ranged from 0.1 to 5.1 m/s and from 0.01 to 2.0 m/s, respectively. The measured void fractions ranged from 0.02 to 0.83. Electrical impedance void meters at four axial locations were used to measure the void fraction. This data was verified through comparison with previous data sets and models. The temporal variation in the void fraction signal was used to characterize the flow regime through use of the Cumulative Probability Density Function (CPDF). The CPDF of the signal was used with a Kohonen Self-Organized Map (SOM) to classify the flow regimes at each measurement port. The three flow regimes used were termed bubbly, cap-bubbly, and churn flow. The resulting flow regime maps matched well with the maps developed previously through other methods. Further, the flow regime maps matched well with the criteria which were proposed based on Mishima and Ishii's (1984) criteria.
Oxytocin induced a biphasic increase in the intracellular Ca2+ concentration of porcine myometrial cells: participation of a pertussis toxin-insensitive G-protein, inositol 1,4,5-trisphosphate-sensitive Ca2+ pool, and Ca2+ channels

This study investigated the underlying mechanisms of oxytocin (OT)-induced increases in intracellular Ca 2+ concentrations ([Ca 2+ ] i ) in acutely dispersed myometrial cells from prepartum sows. A dose-dependent increase in [Ca 2+ ] i was induced by OT (0.1 nM to 1 μM) in the presence and absence of extracellular Ca 2+ ([Ca 2+ ] e ).[Ca 2+ ] i was elevated by OT in a biphasic pattern, with a spike followed by a sustained plateau in the presence of [Ca 2+ ] e . However, in the absence of [Ca 2+ ] e , the [Ca 2+ ] i response to OT became monophasic with a lower amplitude and no plateau, and this monophasic increase was abolished by pretreatment with ionomycin, a Ca 2+ ionophore. Administration of OT (1 μM) for 15 sec increased inositol 1,4,5-trisphosphate (IP 3 ) formation by 61%. Pretreatment with pertussis toxin (PTX, 1 μg/ml) for 2 hr failed to alter the OT-induced increase in [Ca 2+ ]; and IP 3 formation. U-73122 (30 nM to 3 μM), a phospholipase C (PLC) inhibitor, depressed the rise in [Ca 2+ ] i by OT dose dependently. U-73122 (3 μM) also abolished the OT-induced IP, formation. Thapsigargin (2 μM), an inhibitor of Ca 2+ -ATPase in the endoplasmic reticulum, did not increase [Ca 2+ ] i . However, it did time-dependently inhibit the OT-induced increase in [Ca 2+ ] i . Nimodipine (1 μM), a voltage-dependent Ca 2+ channel (VDCC) blocker, inhibited the OT-induced plateau by 26%. La 3+ (1 mM), a nonspecific Ca 2+ channel blocker, abrogated the OT-induced plateau. In whole-cell patch-clamp studies used to evaluate VDCC activities, OT (0.1 μM) increased Ca 2+ current (I Ca ) by 40% with no apparent changes in the current-voltage relationship. The OT-induced increase in I Ca reached the maximum in 5 min, and the increase was abolished by nimodipine (1 μM). These results suggested that (1) activation of OT receptors in porcine myometrium evokes a cascade in the PTX-insensitive G-protein-PLC-IP 3 signal transduction, resulting in an increase in [Ca 2+ ] i ; (2) the OT-induced increase in [Ca 2+ ] i is characterized by a biphasic pattern, in which the spike is predominately contributed by the intracellular Ca 2+ release from the IP 3 -sensitive pool, and to a lesser extent by Ca 2+ influx, whereas the plateau is from increased Ca 2+ influx; and (3) the influx is via VDCC and receptor-operated Ca 2+ channels
Experimental Demonstration of Hybrid Lattice Photonic Crystal Directional Couplers as Wavelength Selective Filters

We demonstrate a hybrid of rectangular and triangular lattices photonic crystal directional coupler. Both the FDTD and experimental results confirmed that the dispersion properties determined this extrumely frequency sensitive device.
The impact of reputation on analysts’ conflicts of interest: Hot versus cold markets

Abstract During periods of high IPO underpricing, unaffiliated all-star analysts from high reputation banks issue fewer strong-buy recommendations while unaffiliated all-star analysts from low reputation banks do not change their level of optimism. In contrast, unaffiliated non-star analysts from both high and low reputation banks issue more strong-buy recommendations. Consistent with the results on analyst optimism, the market reacts more favorably to strong-buy recommendations by unaffiliated all-star analysts from high reputation banks than other unaffiliated analysts during high IPO underpricing periods. Finally, we find that unaffiliated non-star analysts from low reputation banks reduce their coverage following an SEO if they are not selected as a part of the managing syndicate. Collectively, our results indicate that during periods of high IPO underpricing unaffiliated analysts face conflicts of interest, but personal-level reputation, and to a lesser extent bank-level reputation, plays a role in reducing this bias.
Deformation and annealing textures of copper deformed in plane strain and by rolling

Abstract Rolling is considered to result in plane strain deformation under certain conditions. The texture which results from rolling has been modelled under the assumption of plane strain deformation and also with some relaxation of constraints imposed by the plane strain criterion. The texture which results from the heavy cold rolling of copper and aluminum is very pronounced and generally results in the cube texture on annealing. In this paper a comparison between the textures of copper cold rolled and cold deformed by plane strain compression were examined. Of particular interest in the present study is to see whether there is any difference in the formation of cube texture on recrystallization of the specimens deformed by these two methods. Such an investigation has not been reported in the past. The deformation textures of copper channel die (plane strain) deformed to levels of 80%, 90% and 95% were found to be very similar to that of cold-rolled copper. At reductions of 80% and 90%, the channel-die-deformed copper also produced a stronger cube texture on recrystalization than did the rolled copper. However, at 95% reduction the reverse appeared to be the case. The intensity of the texture due to twins of the cube grains was found to increase slightly compared with the dramatic increase in cube intensity with increasing cold reduction for both rolled and channel-die-deformed specimens.
Nanotechnology and the public: Effectively communicating nanoscale science and engineering concepts

Researchers are faced with challenges when addressing the public on concepts and applications associated with nanotechnology. The goal of our work was to understand the public’s knowledge of nanotechnology in order to identify appropriate starting points for dialog. Survey results showed that people lack true understanding of concepts associated with atoms and the size of the nanoscale regime. Such gaps in understanding lead to a disappointing lack of communication between researchers and the public concerning fundamental concepts in nanoscale science and engineering. Strategies are offered on how scientists should present their research when engaging the public on nanotechnology topics.
Developmental expression of lipoxygenases in soybeans

Abstract The developmental expression of lipoxygenase(s) (LOX) was investigated in different soybean Glycine max L. Merr. tissues. Both LOX 1 and LOX 2 + 3 were observed to be present at high levels in axes and cotyledons as determined by Ouchterlony double diffusion, Western immunoblotting and conjugate diene activity assays. LOX 1 was not detectable in any other tissue. Axes and cotyledons contained high levels of LOX 2 + 3 as did pods, small leaves and in lesser amounts medium leaves, large leaves, roots ad stems. Northern analysis that the steady state level of mRNA coding for all three seed LOXs was high only in embryos. This very high expression of LOX in axes in comparison to cotyledons, which is the tissue generally thought to have the highest LOX activity, suggest that lipoxygenase might play a role in embryo development, growth or germination. Unlike LOX 1 or LOX 2, LOX 3 was present in a number of forms with slightly different pI values. A LOX isozyme from leaves was found too be different immunologically and had an altered pI when compared to the three seed LOXs, indicating that soybean leaves contain a LOX that is different that any of the previously characterized seed LOXs.