cssi/SciSciGPT-SciSciNet huggingface dataset:
Morphology of Si(100) surfaces exposed to a remote H plasma

This study addresses the formation of roughness and near surface defects on Si(100) surfaces that are exposed to a remotely excited H plasma. The remote H plasma processing can be employed for in situ wafer cleaning. Atomic force microscopy, transmission electron microscopy, and residual gas analysis are used to measure the surface roughness, the near surface defects, and the etching, respectively. For remote H plasma exposures at substrate temperatures ≤300 °C, etching is observed along with a significant increase in the surface roughness and the formation of platelet defects in the near surface region. As the substrate temperature is increased to above 450 °C, etching is significantly reduced and no subsurface defects or increases in surface roughness are observed.
Managing Conflicts in Relational Contracts

A manager and a worker are in an infinitely repeated relationship in which the manager privately observes her opportunity costs of paying the worker. We show that the optimal relational contract generates periodic conflicts during which effort and expected profits decline gradually but recover instantaneously. To manage a conflict, the manager uses a combination of informal promises and formal commitments that evolves with the duration of the conflict. Finally, we show that liquidity constraints limit the manager’s ability to manage conflicts but may also induce the worker to respond to a conflict by providing more effort rather than less. (JEL C73, D74, D86, J33, J41, M12) Relational contracts often suffer from conflicts during which workers punish managers for broken promises. A common cause for such conflicts is disagreement over the availability and efficient use of funds. In a typical conflict of this sort, workers demand that a bonus be paid while managers insist that the necessary funds are either nonexistent or would be better spent on something else, such as an exceptional investment opportunity. One source of disagreement over the availability and efficient use of funds is asymmetric information. Managers are typically better informed about the challenges and opportunities that their firms face and therefore often have private information about the opportunity costs of paying their workers. The aim of this article is to explore optimal relational contracts in such a setting. For this purpose, we examine the repeated relationship between a manager and a worker in which the manager’s opportunity costs of paying the worker are stochastic and privately observed by her. In the optimal relational contract, the manager promises a bonus if opportunity costs are low but none if they are high. Conflicts therefore arise whenever the manager does not pay the bonus. To manage these conflicts, the manager relies on a combination of informal promises and formal commitments that evolves with the duration of the conflict. As a result, effort and expected profits decline during a conflict only gradually and then recover instantaneously. The same pattern is repeated over time.
Clustering, cold work, and the Mössbauer effect doublet structure in Cu-Ni-Fe alloys

Abstract The doublet structure observed in the high temperature Mossbauer effect spectra of Cu-Ni-Fe alloys is present in a random ally as well as in a metallurgically clustered alloy. The structure of the doublet is distorted by cold work.
APP substitutions V715F and L720P alter PS1 conformation and differentially affect Aβ and AICD generation

The 37–43 amino acid Ab peptide is the principal component of b-amyloid deposits in Alzheimer’s disease (AD) brain, and is derived by serial proteolysis of the amyloid precursor protein (APP) by b- and c-secretase. c-Secretase also cleaves APP at Val50 in the Ab numbering (e cleavage), resulting in the release of a fragment called APP intracellular domain (AICD). The aim of this study was to determine whether amino acid substitutions in the APP transmembrane domain differentially affect Ab and AICD generation. We found that the APPV715F substitution, which has been previously shown to dramatically decrease Ab40 and Ab42 while increasing Ab38 levels, does not affect in vitro generation of AICD. Furthermore, we found that the APPL720P substitution, which has been previously shown to prevent in vitro generation of AICD, completely prevents Ab generation. Using a fluorescence resonance energy transfer (FRET) method, we next found that both the APPV715F and APPL720P substitutions significantly increase the distance between the N- and C-terminus of presenilin 1 (PS1), which has been proposed to contain the catalytic site of c-secretase. In conclusion, both APPV715F and APPL720P change PS1 conformation with differential effects on Ab and AICD production.
Depression Before and After 9/11: The Interactive Relationship of Internal and Chance Health Locus of Control Beliefs

This study extends the body of scholarship on the stress process by comparing levels of depressive symptomatology before and after the terrorist attacks of 9/11 among students enrolled at a university far outside of the areas in which the attacks occurred and by examining the complex interactive relationship between symptoms of depression and the beliefs that one's own actions and chance occurrences can affect health outcomes (health locus of control beliefs). Findings indicate that (a) students who participated in the study after 9/11 reported significantly higher levels of depressive symptomatology and (b) the belief that one's own actions can affect health outcomes was significantly associated with fewer symptoms of depression only among students who also believed that chance can have an impact on health. These findings support Wong and Sroule's model of health locus of control “realism.”
Concordance of Self-Report and Measured Height and Weight of College Students

Abstract Objective This study examined associations between college students' self-report and measured height and weight. Methods Participants (N = 1,686) were 77% white, 62% female, aged 18–24 years (mean ± SD, 19.1 ± 1.1 years), and enrolled at 8 US universities. Body mass index (BMI) was calculated for self-report (via online survey); trained researchers measured height and weight and categorized them as normal (18.5 to Results Concordance of self-report vs objectively measured BMI groups using chi-square revealed that 93% were accurate, 4% were underestimated, and 2.7% were overestimated. Pearson correlations and adjusted linear regression revealed significant associations between self-report and measured BMI ( r = .97; P R 2 = .94). Concordance was also high between BMI categories (kappa = 0.77; P Conclusions and Implications Findings provide support for the utility of self-report height and weight for survey research in college students.
Model consequences and model affect: Their effects on imitation

Children’s imitation of a buttonpressing response was assessed as a function of model consequences and model affect. Three levels of model affect (positive, neutral, and negative) were orthogonally combined with three levels of model consequences (positive, neutral, and negative). There were no significant main or interaction effects. However, under positive model affect, subjects who observed the positive consequences model imitated significantly more than subjects who observed the no consequences model. A difference between comparable groups was not found under neutral model affect. These findings were replicated in a second experiment.
Assassination and Conflict Resolution in Laos

Ten cases of political homicide in Laos were intensively studied, with particular attention to the assassin, the victim, the homicidal event, the provocation, and the social context. Each assassination provided a resolution for a social dilemma which had proven refractory to other means of social problem solving. Certain demographic characteristics and psycho-social correlates of political homicide in Laos resemble those of other cultures.
Cerebral revascularization: a review.

A review of the development and current methods of surgical revascularization of the cerebral circulation is presented. In addition to the conventional superficial temporal artery to middle cerebral artery (STA-MCA) bypass, the techniques of interposition vein grafting and vertebrobasilar revascular
Understanding the black–white school discipline gap

Abstract At state and national levels, black students are more likely to be suspended from school, and conditional on misbehavior, receive stiffer penalties when compared with white students. Racial bias is often cited as a primary contributor to these gaps. Using infraction data from North Carolina, I investigate gaps in punishment within and across schools, and explore how student–teacher and student–principal race interactions affect discipline. I find a significant statewide gap in discipline that is largely generated by cross-school variation in punishment. In addition, there is little evidence that black students are treated differentially according to teacher or principal race.
Computer simulations of mass transport for nonidentical interacting molecules.

Abstract We have developed a system for simulating the mass transport properties of interacting nonidentical macromolecules where the association is of the form A + B ⇄ C , C + B ⇄ D . Our simulation programs operate in a minicomputer (PDP 1104) with 16K of core and provide results identical to methods previously usable only with large computers. We use a rectangular approximation for the centrifuge cell which greatly simplifies calculation, although it introduces a few percent error into any attempt at quantitative fitting of actual data. The program as written is directly applicable to gel chromatography, simply by substitution of flow for centrifugal field and dispersion for diffusion. Simulations of centrifuge results have been compared with experimental results for two systems which have been proposed to fit the association pattern described—nitrogenase components and an antigen-antibody interaction. In both cases the results of our simulations suggest that the accepted interpretation of the experimental results may need to be modified. For the antigen-antibody interaction, the presence of multivalent higher order complexes apparently is required to explain the centrifuge results. For nitrogenase, one cannot readily distinguish the case of association to form both 1:1 and 1:2 molar complexes from that of formation of only the 1:1 complex on the basis of the published data. Criteria for making such a discrimination are discussed.
Use of ultrasonic nebulizer during anesthesia.

Abstract With an ultrasonic nebulizer of low output such as the HNE we used, the input of fluid into the pulmonary system in newborn puppies is 1 ml/kg/hr. Caution should be used with higher-output nebulizers. With an ultrasonic nebulizer of low output in the anesthesia circuitry, a reasonable formula for fluid maintenance during operation is 5 ml/kg/hr. Without a nebulizer, this should be increased to 6 ml/kg/hr in neonates.
Rationale for decreasing the number of days of the hormone-free interval with use of low-dose oral contraceptive formulations.

The developers of the first oral contraceptive (OC) initially synthesized an orally active progestin that inhibited ovulation. However during the process of synthesizing norethynodrel the first oral active progestin a small amount of the estrogen mestranol was also synthesized. Therefore the first OC which was introduced in 1960 consisted of 9.85 mg of norethynodrel and as a result of the synthesizing process 0.15 mg of mestranol. The developers decided to administer this formulation once daily for 21 days followed by 7 hormone-free days to produce regular “natural” cyclic bleeding episodes that would ensure a user that she was not pregnant. During the 7 hormone-free days the superficial portion of the endometrium was sloughed producing a withdrawal bleeding episode that simulated menstruation. With the high doses of hormones used in the early OCs the long half-life of norethynodrel caused continued suppression of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels during the hormone-free interval thereby preventing follicular growth estradiol synthesis and ovulation during the days when the steroids were not being ingested. (excerpt)
Comparison of the effects of prototypical behavioral stimulants on locomotor activity and rotational behavior in rats

The present study was performed to characterize on rotational behavior the dose- and time-effect relationship of four prototypical behavioral stimulants that interact with dopamine systems via different mechanisms of action. Drug effects on rotational behavior was compared with effects on locomotor activity. The drugs examined were apomorphine (0.03-1.0 mg/kg), d-amphetamine (0.1-3.0 mg/kg), cocaine (3.0-56 mg/kg), and caffeine (10-100 mg/kg). SKF-38393 (0.3-10 mg/kg), a dopamine receptor agonist that has only modest effects on locomotor activity, was tested as a comparison. In rats with unilateral 6-hydroxydopamine (6-OHDA)-induced lesions of the nigrostriatal tract, d-amphetamine and cocaine dose dependently increased both the duration and the maximum number of turns/10 min, whereas apomorphine and caffeine increased only the duration of turning. There was a significant correlation of the effects of the four drugs on rotational behavior with effects on locomotor activity, but effects across drugs were not identical. Dose-response curves revealed potency differences among drugs in their effects on the two behaviors (e.g., apomorphine stimulated rotational behavior at a lower dose than it stimulated locomotor activity, whereas the converse was true with caffeine). Different mechanisms of action of these drugs might account for the differences in their effects on these behaviors.
Using contingent valuation to estimate the willingness of tourists to pay for urban forests: A study in Savannah, Georgia

Abstract This study estimated the monetary value of urban forests’ non-priced benefits to tourists. Data collected by a face-to-face self-administered survey of urban tourists in Savannah, Georgia, USA were used to estimate tourists’ willingness to pay (WTP) for urban forests by the contingent valuation method. Individual WTP was found higher among tourists with graduate school education. Results suggested that WTP for urban forests also increased significantly with income and destination loyalty of the tourists. Estimated mean and median WTP values were $11.25 (95% confidence interval: $7.34, $15.16) and $2.10 (95% confidence interval: $1.38, $2.82), respectively. Based on the estimated mean WTP, annual value of urban forests to tourists in Savanna in 2009 ranged from a minimum of $81 million to a maximum of $167 million with a 95% confidence interval. The annual value was $11.55 million (95% confidence interval: $7.59 million, $15.51 million) based on the estimated median WTP and assuming at least 50% of the tourists in Savannah would pay the median amount. As the mean was greatly influenced by extreme WTP values in the data, the annual value based on the median value was a more conservative estimate.
Rigorous Separation Design. 1. Multicomponent Mixtures, Nonideal Mixtures, and Prefractionating Column Networks

Currently, there is a lack of reliable computational methods to automatically synthesize separation networks within specific product targets. Computational methods exploring the combinatorial wealt...
A Kantian duty to commit suicide and its implications for bioethics.

Aside from one unfortunate phrase, I find the thrust of Dennis Cooley's analysis of the moral duty of the soon-to-be demented to commit suicide to be consistent with both Kant's writing and with th...
Supply Response in the U.S. Sheep Industry

A dynamic supply model of the U.S. sheep industry is constructed. The model incorporates restrictions on fixed capital and the demographic characteristics of the breeding flock. The model is estimated using least squares techniques and simulated to generate a matrix of short- and intermediate-run elasticity estimates. The estimates indicate that sheep supply is positively related to lamb price in the short run and the intermediate run (ten plus years), although inelastic in the short run. The supply response to wool price also is positive and quite elastic in the intermediate term. These results imply that both lamb and wool prices are important to the maintenance of the U.S. sheep industry.
Adenosine 3',5'-Cyclic Phosphate: Stimulation of Steroidogenesis in Sonically Disrupted Adrenal Mitochondria

Adenosine 3'5'-cyclic phosphate stimulated the conversion of added cholesterol to pregnenolone in "coupled" rat adrenal mitochondria provided with succinate, and in "leaky" mitochondria fortified with reduced nicotinamide adenine dinucleotide phosphate. Adenine nucleotides other than adenosine 3',5'-cyclic phosphate did not duplicate these actions. The cyclic nucleotide was also effective in supernatants from sonically disrupted mitochondria. The minimum effective concentration was 50 micromoles per liter or less. The results suggest that adenosine 3',5'-cyclic phosphate stimulates corticosteroidogenesis by activating the mitochondrial enzymes which are rate-limiting in the utilization of cholesterol.
Economic Feasibility of Substituting Fresh Poultry Litter for Ammonium Nitrate in Cotton Production

ABSTRACT Chicken broilers are Alabama's number one agricultural commodities, based on total state cash receipts of $1.7 billion in 1997. As of the beginning of the fourth quarter of 1998, the number of broiler chicks hatched was approximately 4 percent greater than in the previous year and total egg production in Alabama was 1.4 percent above the 1997 level. This poultry industry produces enormous amount of litter, which has been utilized as a fertilizer in crop production. The paper evaluates the economic feasibility of substituting broiler litter for ammonium nitrate in cotton production. Data utilized was from a field experiment conducted at Bell Mina Research Station, Alabama 1996–97. Simple linear programming was used for the analysis and sensitivity analysis was performed to determine the level of stability of the results of the basic models. The results indicate that at a maximum distance of 124 miles, fresh litter is a feasible substitute for ammonium nitrate in northern Alabama.
Micro-to-Macro Simulation: A Primer With a Labor Market Example

Simulation models, now widely used in the physical sciences, can also help economists in depicting the actions and interactions of individuals and firms through time. Such models can be built and run on any personal computer. They can illuminate a wide variety of issues that are difficult to analyze with an economist's conventional tool-kit and are especially useful in studying dynamic processes. Microsimulation models allow the analyst to produce simulated aggregate time series that are rigorously consistent with the assumptions made about behavior on the micro level. Thus, simulations provide a means of bridging the micro-macro split in economic analysis. This article provides an introduction to microsimulation: how it works, how to do it, its potential, and its drawbacks. It then allows readers, even those with no experience in computer programming, to work through the details of a simple microsimulation model. Readers can put this model on their PCs, watch it run through its paces, and experiment with their own modifications. With this model as an example, it should be fairly easy to create programs for new models on other subjects for use in theoretical exploration, empirical research, or classroom demonstrations. The demonstration model I present depicts the experience of individual workers during recession and recovery in the labor market. As the model runs, its internal "Census Bureau" performs surveys on the microlevel, and sums up to macrolevel variables. The model is simple, but it has some interesting applications. After explaining how to set it up, I use it to explore the effect of unemployment insurance on the level of unemployment, and to point up a common fallacy in current labor market literature.
Condensation polymers from diisocyanates with dihydrazides and hydrazine

Diisocyanates condense readily with hydrazine or hydrazine hydrate to give polyureylenes with the structure: Similarly, dihydrazides (NH2NHCOR′CONHNH2) condense with diisocyanates to give polymers with the structure: Tough films and fibers can be prepared from these polymers by conventional techniques. Solutions of some of these polymers are relatively unstable at elevated temperatures, the polymer apparently reverting to starting materials. Attempts to stabilize the solutions were unsuccessful.
Nutrient Limitation of the Macroalga Enteromorpha intestinalis Collected along a Resource Gradient in a Highly Eutrophic Estuary

We conducted a laboratory experiment to quantify nutrient (nitrogen and phosphorus) limitation of macroalgae collected along a gradient in water column nutrient availability in Upper Newport Bay estuary, a relatively nutrient-rich system in southern California, United States. We collectedEnteromorpha intestinalis and water for use in the experiment from five sites ranging from the lower end of the estuary to the head. Initial algal tissue N and P concentrations and molar N∶P ratios—as well as water column NO3 and total Kjeldahl nitrogen (TKN)—increased along a spatial gradient from the lower end toward the head. Water column soluble reactive phosphorus (SRP) varied among sites as well but did not follow a pattem of increasing from the seaward end toward the head. Algae from each site were assigned to one of four experimental treatments: control (C), nitrogen enrichment (+N), phosphorus enrichment (+P), and nitrogen and phosphorus enrichment (+N+P). Each week for 3 wk we replaced the water in each unit with the appropriate treatment water to mimic a poorly flushed estuary. After 3 wk, the degree of nutrient limitation ofE. intestinalis varied spatially with distance from the head of the estuary. Growth ofE. intestinalis collected from several sites increased with N enrichment alone and increased further when P was added in combination with N This indicated that N was limiting and that when N was sufficient, P became limiting. Sites from whichE. intestinalis exhibited nutrient limitation spanned the range of background water column NO3 (12.9±0.4 to 55.2±2.1 μM) and SRP (0.8±0.0 to 2.9±0.2 μM) concentrations. Algae that were N limited had initial tissue N levels ranging from 1.18±0.03 to 2.81±0.08% dry weight and molar N∶P ratios ranging from 16.75±0.39 to 26.40±1.98.
Comment on “Navier–Stokes Revisited,” H. Brenner, Physica A 349 (2005) 60

Abstract Brenner [Physica A 349 (2005) 60] has proposed that the diffusion creep velocity resulting from a concentration gradient along a surface is a consequence of a no-slip boundary condition on the fluid volume average velocity. It is shown that the proposed formula for the creep velocity contradicts Graham's law for isobaric diffusion in a passage, and is also in disagreement with a number of kinetic-theory studies.
Gallium nitride on silicon for consumer and scalable photonics

Gallium Nitride (GaN) is a unique material system that has been heavily exploited for photonic devices thanks to ultraviolet-to-terahertz spectral tunability. However, without a cost effective approach, GaN technology is limited to laboratory demonstrations and niche applications. In this investigation, integration of GaN on Silicon (100) substrates is attempted to enable widespread application of GaN based optoelectronics. Controlled local epitaxy of wurtzite phase GaN on on-axis Si(100) substrates is demonstrated via metal organic chemical vapor deposition (MOCVD). CMOScompatible fabrication scheme is used to realize [SiO2-Si{111}-Si{100}] groove structures on conventional 200-mm Si(100) substrates. MOCVD growth (surface treatment, nucleation, initiation) conditions are studied to achieve controlled GaN epitaxy on such grooved Si(100) substrates. Scanning electron microscopy and transmission electron microscopy techniques are used to determine uniformity and defectivity of the GaN. Our results show that aforementioned groove structures along with optimized MOCVD growth conditions can be used to achieve controlled local epitaxy of wurtzite phase GaN on on-axis Si(100) substrates.
Theory of surface enhanced Raman scattering

It is now generally accepted that more than one mechanism could be at work in enhancing the Raman signal from molecules adsorbed onto a rough surface. In this paper we present a simple surface coverage, surface roughness dependent model that accounts for one such mechanism. According to our model, each adsorbate is subjected to both polarizing and depolarizing fields from its oscillating neighbors. Competition between these two fields is shown to determine the magnitude of signal enhancement.
The Crystal and Molecular Structure of Bis(cyclopentadienyldicarbonylchromium) (CrCr)

Abstract The crystal structure of bis(cyclopentadienyldicarbonyl-chromium) has been determined by x-ray diffraction. The compound crystalizes in the triclinic system, space group P1¯(C1i, No. 2) with unit cell parameters: a, 7.829(3); b, 14.543(6); c, 6.588(2)A; α, 94.67(3), β, 110.70(3); γ, 104.04°(3); V, 699.1(4)A3; z=2. There are two independent molecules per unit cell located at the inversion centers at O,O,O and O, 1/2, O. The Cr Cr bond distances are, respectively 2.200(3) and 2.230(3), thus supporting their formulation as triple bonds. The Cp Cr Cr angles in the two molecules are 165.0° and 158.7°, respectively. The structural features are compared with those of Cp2Mo2(CO)4, which has a linear Cp Mo Mo Cp axis; and the differences rationalized in terms of electronic interactions of the Cp-ligand with the orbitals of the M2 unit. The differences observed in the structures of the two independent molecules are also related to the proposed bonding model and to packing considerations.
Pediatric lateral distraction injury of the lumbar spine: a case report

Abstract Background context Lateral distraction injuries represent a very rare pattern of injury with only five cases reported in the literature. Such injuries are a result of high-energy trauma and have a high association with severe concomitant injuries. All previous reports of this injury are in skeletally mature individuals, and this has not been previously described in young children. Purpose To report a case of a lateral distraction injury in a young child secondary to improper seat belt use. Study design Case report and review of the literature. Patient sample Case report of an 8-year-old girl involved in a highway speed head-on collision. Methods We report here on an 8-year-old girl who was lying supine in the backseat of a motor vehicle while wearing a lap belt when the vehicle was involved in a high-speed motor vehicle crash. She presented with focal back pain, abdominal pain, and a seat belt sign. Imaging demonstrated focal coronal plane deformity with unilateral ligamentous disruption. The patient was diagnosed with a ligamentous lateral distraction injury of the lumbar spine. This injury was treated with open reduction and posterior spinal fusion with pedicle screw fixation. Results The patient tolerated the procedure well and had an uneventful postoperative course. Conclusions In this case, we describe a lateral distraction injury in a young child secondary to improper seat belt use. This represents the first description of such an injury in this age group, and this case highlights the spectrum of injury caused by improper seat belt use in the pediatric population.
Predicting the Thermodynamic Stabilities and Oxidation Resistances of Silicide Cermets

Available infornaation on the thermodynamic stabilities of transition metal silicides is summarized and is used to demonstrate the calculation of the stability of silicidemetal mixtures. The cause of the outstanding oxidation resistance of certain silicides is analyzed, and the results are used to predict high oxidation resistance for several untested disilicides. Thermodynamic and structural arguments are applied to the prediction of compositions of thermodynamically stable and oxidation-resistant cermets.
Calcium and the skin.

Mother did not know how right she was in exhorting her children to drink milk. In addition to building strong bones and teeth, data have been accumulating that on an "ionic" level calcium regulates cell functions as diverse as insulin secretion, muscle contraction, and mast cell degranulation. In addition, calcium plays an important role in regulating proliferation and differentiation of the skin. Nature maintains steep calcium gradients in and outside cells that allows calcium to act as an internal messenger, translating extracellular signals into cellular responses. 1 Calcium is normally stored in the endoplasmic reticulum and mitochondria, and a low, free intracellular concentration in the cytoplasm is maintained (10- 7 mol/L). However, the free intracellular calcium is the physiologically active internal calcium. Calcium levels outside the cells and in the storage compartments are 10000 times higher than the free intracellular calcium concentration. Transport of small amounts of calcium from the
II. Introduction to a reappraisal of fear and trembling 1

The idea of a knighthood of faith which involves a ‘teleological suspension of the ethical‘ is the most arresting feature of Kierkegaard's Fear and Trembling. It amounts to a theological shock treatment. It is therefore understandable that critics and commentators who have discussed Fear and Trembling have focused their attention almost exclusively on this extreme notion of faith. Their preoccupation has been unfortunate, however.
Stability of AMP:pyrophosphate phosphoribosyltransferase, an autosomally determined enzyme in an X-linked disease. Identification of a destabilizer.

Abstract The stability of AMP: pyrophosphate phosphoribosyltransferases (AMP pyrophosphorylase) from erythrocytes of normal subjects and patients with Lesch-Nyhan disease has been studied. Storage of intact cells, but not lysates, led to increased heat stability of the normal but not the Lesch-Nyhan enzyme. Passage of lysates of stored normal erythrocytes through Sephadex gave a further increase in the heat stability of AMP pyrophosphorylase. Boiled extracts of stored erythrocytes contained a potent destabilizer of the enzyme which was identified as hypoxanthine. A heat stable form of AMP pyrophosphorylase was generated by pre-incubation with 5-phosphoribosyl i -pyrophosphate, a substrate. These observations suggest that the level of AMP pyrophosphorylase in the erythrocyte may be controlled by the relative concentrations of stabilizer and destabilizer. A variety of purine derivatives were destabilizers of the enzyme. Compounds with 6-amino substituents were active with the normal and Lesch-Nyhan enzyme but 6-hydroxypurines affected only normal AMP pyrophosphorylase. AMP pyrophosphorylases were purified 200-fold from normal and Lesch-Nyhan erythrocytes. The purified enzymes retained some of the differences in stability seen with crude lysates, but the destabilizing effect of purines was lost.
Membranous staphylococcal enteritis after antibiotic therapy; report of two cases.

Two fatal cases are reported of membranous enteritis associated with Staphylococcus aureus septicemia and the presence of staphylococci in the fibrinous enteric casts. Attention is directed to this as an apparent sequel of antibiotic therapy, consequent upon radical alterations of the normal intestinal bacterial relationships.
Minimality of some group-extension-type flows in terms of eigenvalues

We use our criterion for minimality of restrictions of compact minimal abelian flows to characterize minimality of group-extensions, products and restrictions of suspensions in terms of eigenvalues. In particular, we get a new proof of a theorem of Parry about minimality of group-extensions and generalize some theorems about minimality of products and restrictions of suspensions.
Melting Relations of the Common Rock-Forming Oxides

Geological science is concerned with the nature of the materials of the earth and particularly with the processes by which earth materials have been changed and modified. Laboratory studies of the melting behavior of the common rock-forming oxides have been an important adjunct to the observations of the field geologist. For the past fifty years investigators at the Geophysical Laboratory have been obtaining quantitative information on the melting relations of many of the important rock-forming minerals. These studies of the fundamental chemistry of igneous and metamorphic rocks have yielded much information of value to ceramists, metallurgists, and mineral technologists. This paper summarizes the most important phase-equilibrium studies of unary, binary, ternary, quaternary, and portions of quinary systems of the common rock-forming oxides-SiO2, Al2O3, FeO, Fe2O3, CaO, MgO, Na2O, and K2O.
CHEMISTRY OF 5‐PYRIMIDINECARBOXALDEHYDES

Selective hydrolysis of 2-amino-4,6-dichloro-5-pyrimidinecarboxaldehyde, 2, gave 2-amino-4-chloro-1,6-dihydro-6-oxo-5-pyrimidinecarboxaldehyde, 5. The oxime of 2 rearranged to 2-amino-4-chloro-1,6-dihydro-6-oxo-5-pyrimidinecarbonitrile, 8. Reaction of 8 with 4-phenylbutylamine resulted in the displacement of the 4-chloro atom to give compound 9. Hydrolysis of the cyano function of 9 gave amides 12, 13, and 14 depending on reaction conditions. A discussion of the 1H-nmr spectrum of 2-amino-1,6-dihydro-6-oxo-4-[(4-phenylbutyl)amino]-5- pyrimidinecarboxaldehyde, 6, is presented.
A Bayesian expert judgement model to determine lifetime distributions for maintenance optimisation

Preventive maintenance of mechanical equipment subject to random failures requires a lifetime distribution to establish an optimal maintenance interval. Typically, the optimal maintenance interval under an age replacement regimen is obtained by minimising the long term average cost of the maintenance activity. Only when the cost of maintaining the equipment preventively is less than the cost of failure of the equipment, can preventive maintenance be worthwhile. In practical contexts with an effective preventive maintenance policy, the estimation of such a lifetime distribution is complicated due to a lack of failure time data despite an abundance of right censored data, i.e. survival data of the component up to the time it was preventively maintained. Herein, we shall present a model for eliciting lifetime distributions via a histogram technique reminiscent of the method proposed by Van Noortwijk et al. (Van Noortwijk, J.A., et al., 1992. On the use of expert opinion for maintenance optimization. IEEE Tra...
CYTOLOGICAL STUDIES IN THE GENUS DESMODIUM; SOME CHROMOSOME COUNTS

THE GENUS Desmodium, commonly known as tick clover or beggarweed, contains over 250 species of annual or perennial herbs, shrubs, and small trees. The genus is widely distributed over the temperate and tropical regions of both hemispheres with many species occurring in North and South America. A number of the species are now pan-tropical in their distribution. According to Taubert (1894), the genus Desmodium is placed in the sub-tribe Desmodium of the tribe Hedysareae, sub-family Papilionoideae, family Leguminosae. This paper is the first of a series of reports on cytological studies in the genus. It includes confirmation of some previously reported counts and counts for eight species not reported previously. Early reports (Senn, 1938; Young, 1940) indicated that the basic chromosome number is x = 11. Turner and Fearing (1959) reported 2n = 20, for Desmodium salicifolium. This count by Turner and Fearing was the first report of a different base number, x = 10, thus indicating that the genus is not monobasic as reported earlier. One other report (Pritchard and Gould, 1964) gave 2n = 20 for D. gyroides. None of the earlier reports gave any indication of polyploidy within the genus.
A modified autoanalyzer II method for the determination of NO3‐N in water using a hollow‐Cd reduction coil

Abstract The Technicon AutoAnalyzer II (AAII) is used routinely by many laboratories for determination of NO3‐N in water. The methodology involves the use of a packed‐Cd column for reduction of NO3‐N to NO2‐N, which subsequently is determined colorimetrically. A newer instrument, the Technicon TRAACS 800, uses a hollow‐Cd coil for NO3 ‐N reduction. A method is described for adapting the hollow‐Cd coil to the AAII for determination of NO3‐N in water samples. This adaptation was found to increase throughput rate and to decrease the time required for column preparation.
Metamagnetic effects in hematite

Abstract In the region of the anti-ferromagnetic-weak ferromagnetic, AF-WF, phase transition of hematite experimental evidence for an unexplained susceptibility peak and for a value of χ⊥(AF)>χ⊥ (WF) has been observed which is based upon the field dependence of the magnetization. It can however be shown that these two effects are due primarily to a misinterpretation of the experimental results which are complicated by the AF-WF phase transition in combination with the inhomogeneities exhibited by most hematite crystals.
Two new subspecies of Herpetomonas muscarum (Leidy, 1856) Kent, 1880.

SYNOPSIS. Herpetomonas muscarum muscarum n. subsp. was isolated from Musca domestica L. In culture at 20 C it assumed the opisthomastigote (up to 15%), double-flagellate and flagellate promastigote forms. At 30 C or with 4% urea added to cultures at 20 C, the proportion of opisthomastigotes was greater (up to 40%). In experimentally infected flies only transient infections, which included both opisthomastigotes and promastigotes, occurred. The promastigotes were 15–30 μ long and the kinetoplast was small and subspherical or transversely elongate. H. muscarum ingenoplastis n. subsp. was isolated from Phormia regina (Meigen). In culture at 20 C almost all individuals were double-flagellate promastigotes 20–40 μ long and less than 1% were opisthomastigotes. At 30 C or with added urea there was no increase in the proportion of opisthomastigotes and the cultures were not vigorous. In experimentally infected flies opisthomastigotes were 5–39% of the population depending on the part of the gut sampled. In all stages the kinetoplast was large (1.5–2.5 μ long) and tear-drop-shaped with the point directed posteriorly. In artificially mixed cultures of H. m. muscarum and H. m. ingenoplastis the former predominated after a short time and eventually survived alone. A mixed culture that was about 98%H. m. muscarum was fed to Phormia regina and produced heavy pure infections of H. m. ingenoplastis, which lasted for 22 days with no indication of decline. No evidence of cyst formation was found in either subspecies.
The space of Lefebvre

The translation of The Production of Space into English is a major event for those, like myself, otherwise lacking access to so much of Lefebvre's work. Of the sixty-six volumes he published before his death last year, only six have previously appeared in this language. The availability of The Production of Space will now help advance for Lefebvre, in the English-speaking countries, the kind of influence he has long had in Europe. Some of the book's contents have filtered into English-only circles through the writings of others (Castells, Harvey, and, most explicitly, Gottdiener);2 some insights have come our way through more or less simultaneous invention. But almost two decades after being first published, the content is rich enough to reward sustained attention. This work makes an important contribution not only to urban theory but, if appropriately understood, to theory more generally.
Nanoparticle-cored dendrimers: synthesis and characterization.

The synthesis and characterization of a group of new dendrimersnamely, nanoparticle-cored dendrimers (NCDs)are described. These materials were obtained by the reduction of hydrogen tetrachloroaurate phase-transferred into toluene in the presence of Frechet-type polyaryl ether dendritic disulfide wedges of generation 1−5. These materials, possessing nanometer-sized gold clusters at the core and dendritic wedges radially connected to the core by Au−S bonds, were analyzed by TEM and TGA, and by UV, IR, and NMR spectroscopies. The number of branching units connected to the core decreased with the generation of the dendritic wedge, and this number changed from 2.18/nm2 for Au−G-2 to 0.27/nm2 for Au−G-5. This result suggests that, in the higher-generation NCDs, a large fraction of the surface area of the metal cluster is not passivated and is therefore available for catalytic activity.
Pressure patterns in the reticulum of the cow

Abstract Two mature holstein cows were used to ascertain reticular pressure patterns. A pressure-sensitive transmitter 2.54 cm in diameter and 20.32 cm long was passed down the esophagus to the reticulum. This transmitter sent a variable frequency signal which was decoded to indicate pressures from zero to 175 mm Hg. Continuous pressures were recorded. Rumination and nonrumination pressures were recorded and correlated to different activities such as standing, resting, drinking, and eating. The average length of contraction cycles was 42 sec in nonrumination whereas the average contraction cycle in rumination was 56 sec. Nonrumination patterns exhibited two pressure peaks per cycle whereas rumination had three peaks per cycle. The time interval between the first and second pressure peak of a cycle was approximately 3 sec in both rumination and nonrumination. In rumination the third pressure peak was approximately 3 sec after the second. Contraction pressure magnitudes varied with external activity of the cow. Peaks within each cycle were of different magnitude, usually the first peak was smaller than the second in nonrumination. During rumination, peak averages were similar for the first two peaks but greater for the third.
Frequency analysis of submerged cylindrical shells with the wave propagation approach

The wave propagation approach is extended to coupled frequency analysis of finite cylindrical shells submerged in a dense acoustic medium. Comparison of the results by the present method and numerical FEM/BEM has been carried out. A finite cylindrical shell enclosed with plate end-caps was modeled for coupled frequency analysis. The first eight coupled natural frequencies were obtained using SYSNOISE. These results are compared with the new method and good agreement has been found. With the new method the effects of shell parameters, m,n,h/R,L/R and boundary conditions, on the coupled frequencies are investigated. The coupled frequency curves are also u-shaped as the uncoupled frequency curves. As the circumferential mode n increases, the difference between the coupled and uncoupled frequencies reduces at small mode n, but increases after the n where the fundamental frequency is achieved. The effects of boundary conditions are significant at small mode n. Due to the coupling effects the transition of fundamental coupled frequency is earlier with the h/R ratios than that of the uncoupled case. Both the coupled and uncoupled frequencies increase with the h/R ratios, but at different rates which show the different coupling effects on the different wave modes. With the present method the calculation of coupled frequency of submerged cylindrical shells is relatively easy, quick but with good accuracy.
Ready, Set, Reset: Stimulus-Locked Periodicity in Behavioral Performance Demonstrates the Consequences of Cross-Sensory Phase Reset

The simultaneous presentation of a stimulus in one sensory modality often enhances target detection in another sensory modality, but the neural mechanisms that govern these effects are still under investigation. Here, we test a hypothesis proposed in the neurophysiological literature: that auditory facilitation of visual-target detection operates through cross-sensory phase reset of ongoing neural oscillations (Lakatos et al., 2009). To date, measurement limitations have prevented this potentially powerful neural mechanism from being directly linked with its predicted behavioral consequences. The present experiment uses a psychophysical approach in humans to demonstrate, for the first time, stimulus-locked periodicity in visual-target detection, following a temporally informative sound. Our data further demonstrate that periodicity in behavioral performance is strongly influenced by the probability of audiovisual co-occurrence. We argue that fluctuations in visual-target detection result from cross-sensory phase reset, both at the moment it occurs and persisting for seconds thereafter. The precise frequency at which this periodicity operates remains to be determined through a method that allows for a higher sampling rate.
Autoregulation of Coronary Blood Flow: Effect of Interarterial Pressure Gradients

In the normal heart, transient and adjusted steady state coronary flow rates in response to changes in perfusion pressure are not significantly affected by collateral flow into and from heart muscle surrounding the area perfused by a test artery. An active autoregulatory adjustment tends to counteract flow changes after perfusion pressure is changed. This adjustment is sometimes sufficient to increase vascular resistance above control values. Usually, however, coronary resistance decreases at higher perfusion pressures even though autoregulation is present. The experiments provide no evidence for reflex control of coronary resistance in response to increases in aortic pressure; the initial flow changes can be accounted for by the corresponding increase in perfusion pressure. It is necessary to examine the entire coronary flow pattern after a sudden change in perfusion pressure in order to formulate concepts which include all the important determinants of coronary blood flow.
Understanding Priorities for Service Attribute Improvement

To improve the overall quality of a service experience, managers often focus on enhancing particular attributes of the service. Yet identifying the attributes to improve—those with the greatest impact on customer satisfaction with the overall service—is often challenging. Generally, improving a poorly performing attribute provides a notable boost to the customer’s perceived overall experience, but further improvements have a diminishing positive effect. The task is further complicated by the fact that the point of diminishing returns, or more generally, the shape of attribute utility curves, likely differs by attribute. Thus, the priorities for attribute improvement may change as service performance changes. Marginal utility analysis (MUA), a new method for understanding the priorities for attribute improvement, is introduced. The method is demonstrated on a sample data set and compared to alternative techniques for understanding priorities including direct measures of customer priorities for improvement,...