cssi/SciSciGPT-SciSciNet huggingface dataset:
2‐(2‐Bromoethyl)‐2‐methyl‐1,3‐dioxolane

(1; X = Br) [37865-96-6] C6H11BrO2 (MW 195.06) InChI = 1S/C6H11BrO2/c1-6(2-3-7)8-4-5-9-6/h2-5H2,1H3 InChIKey = SZLPRRVCSGZARF-UHFFFAOYSA-N (2; X = I) [53750-51-9] C6H11IO2 (MW 242.06) InChI = 1S/C6H11IO2/c1-6(2-3-7)8-4-5-9-6/h2-5H2,1H3 InChIKey = SXVDTZCWOQEFBN-UHFFFAOYSA-N (3; X = Cl) [57398-28-4] C6H11ClO2 (MW 150.60) InChI = 1S/C6H11ClO2/c1-6(2-3-7)8-4-5-9-6/h2-5H2,1H3 InChIKey = QGUGADJGHOKRSF-UHFFFAOYSA-N (methyl vinyl ketone equivalent; alkylating agents for attaching a 3-ketobutyl group to various nucleophiles; the derived organometallic reagents attach this group to electrophilic centers such as carbonyl groups; major use in the synthesis of monoprotected 1,4-, 1,5-, and 1,6-diketones and related 1,n-difunctional compounds) Physical Data: X = Cl: bp 40–43 °C/1 mmHg; 73–74 °C/14 mmHg. X = Br: bp 42–46 °C/0.4 mmHg; 64–68 °C/9 mmHg; 84–88 °C/12 mmHg, 88–94 °C/27 mmHg. X = I: decomposes on distillation. Preparative Methods: X = Br or I: addition of methyl vinyl ketone to a two-phase mixture of benzene and conc aq HX, followed by drying of the benzene phase, addition of ethylene glycol, and removal of water with a Dean–Stark trap.1b,2 X = Cl: acetalization of 4-chloro-2-butanone with ethylene glycol;3 the chloro ketone was made by acylation of ethylene4 but, presumably, can also be made as above. Other preparations of these and related 4-halo-2-butanone acetals have been reported.5 Purification: X = Cl or Br: vacuum distillation from a trace of sodium bicarbonate; X = I: filter through a small plug of alumina; the acetal should not be distilled. Handling, Storage, and Precautions: even purified samples contain some β-halo ketone which slowly loses HX, catalyzing further decomposition. Store at ≥0 °C.
Parallel Computation of Surrogate Models for Potential Energy Surfaces

In this paper we describe a parallel algorithm for generating interpolatory approximations to molecular potential energy surfaces. We show how that algorithm can be applied to efficiently model a transition from a stable ground state, to an excited state, and finally to a different stable ground state.
POLYMER EDUCATION IN U.S. COLLEGES AND UNIVERSITIES: REFERENCE SOURCES AND GUIDES

In the 1967 film, The Graduate, Mr. Robinson gave Dust in Hoffman's character, Benjamin, the scene‐stealing career suggestion, “plastics!” Although Benjamin appeared indifferent to the oracle‐like advice, thousands of other graduates have since helped to make plastics, or polymers, a popular career choice. Today, the U.S. polymer‐based industries (plastics, rubber, fibers, paints, films, membranes, coatings, and adhesives) employ more than a million workers and need 10,000 new graduates yearly to support their growth. Yet, despite the emphasis industry and government place on formal training in polymer science and engineering (hereafter called PSE), academia has given the rapidly developing field a cool reception. Science writer Joseph Alper notes:
Differential regulation of collagen, glycosaminoglycan, fibronectin, and collagenase activity production in cultured human adult dermal fibroblasts by interleukin 1-alpha and beta and tumor necrosis factor-alpha and beta

In order to clarify the role played by immunologically derived cytokines in dermal connective tissue synthesis and degradation, we investigated the effect of human recombinant (hu-r) interleukin (IL) 1-alpha and beta, hu-r tumor necrosis factor (TNF)-alpha and beta, hu-r IL 2, and hu-r granulocyte-macrophage colony-stimulating factor (GM-CSF) on the production of collagen, glycosaminoglycan, fibronectin, and collagenase activity by three lines of cultured human adult dermal fibroblasts. Our results show that 24-72 h treatment of confluent fibroblast cultures with IL 1-alpha or beta or TNF-alpha or beta causes concentration (1 to 1 X 10(4) U/ml) dependent increases in collagen, glycosaminoglycan, and collagenase activity production, but decreases in fibronectin production. In contrast, treatment with IL 2 and GM-CSF had no effect on fibroblast functions. The data show that IL 1-alpha and beta and TNF-alpha and beta differentially regulate fibroblast functions, and that increases in catabolic functions like collagenase activity production are more than tenfold greater than increases in anabolic functions like collagen production. When these results are considered along with other reports, they suggest that IL 1 and TNF may play predominately a catabolic role in situ during dermal fibrotic responses by directly inhibiting fibronectin production and indirectly causing the degradation of collagen and glycosaminoglycan by significantly increasing dermal fibroblast elaboration of collagenase and proteoglycanase activities.
Physical studies of RNA involvement in bacteriophage lambda DNA replication and prophage excision.

Abstract Non-diffusible genetic elements in bacteriophage λ DNA replication and λ prophage excision have been analyzed by the DNA-cutting assay of Freifelder and Kirschner (1971) and Freifelder et al. (1972). The mutant ti12, which affects a unique site for replication in or near the origin of replication (Dove et al., 1971), makes λ DNA partially refractory to replicative DNA-cutting. RNA synthesis in the vicinity of the origin, of replication seems to control the susceptibility of λ DNA to replicative DNA-cutting (Dove et al., 1969). Analogously, RNA synthesis in the vicinity of the left-hand prophage terminus seems to control excisional DNA-cutting of derepressed λ DNA, as predicted by the studies of Davies et al. (1972). These physical studies confirm previous genetic analyses and imply that the elements involved act at a very early stage in replication and in excision.
Coupon rationing and rent-seeking bureaucrats

Prices perform an important rationing function in market economies. When government price controls contravene this function, alternative rationing procedures come into play. This note is concerned with formal coupon rationing and, in particular, with the tendency of democratic governments to legally prohibit market exchange of ration coupons. Participants in such a market have nothing to gain and potentially much to lose from such restrictions. Hence, the tendency of policy-makers even to consider, much less adopt, such restrictions might seem rather puzzling. However, it will be argued here that a 'black' market in coupons offers a greater opportunity for bureaucratic rent-seeking than does a white market. In addition, producers of the rationed commodity may also benefit from legal prohibition of coupon exchange. Thus such prohibition may reflect a dominance of bureaucratic and/or producer interest in that government decision. In the case of a shortage created by a price ceiling, three common alternatives to the prohibited price rationing are queueing, supplier favoritism and formal government rationing. Of these three, the latter is likely to have widespread political appeal if the shortage is severe and prolonged. Queueing, for example, simply substitutes a time price for that component of the market-clearing money price which consumers are forbidden to pay and is likely, in many cases, to reduce the consumer's surplus of many individuals to below that which they would achieve in the absence of the price control.1 Reliance on supplier favoritism may also be undesirable from the standpoint of many consumers, especially if the supplier is able to set up an implicit market for his 'favors' which effectively raises the price of the rationed commodity to the consumer. Formal rationing by the government eliminates both of the above sources of added costs to consumers. The government simply distributes among consumers 'rights' to purchase the rationed commodity at the regulated price. At the time of purchase of a unit of the rationed commodity, the consumer must surrender not only the money price of the commodity but
Air Travel Consumer Protection: Metric for Passenger On-Time Performance

The raison d'etre for the national air transportation system (ATS) is the movement of passengers and cargo. Thus, passenger trip time performance is positively correlated with passenger satisfaction, airfare elasticity, and airline profits. Regulatory consumer information available to airline passengers provides measures of trip performance by using the percentage of on-time flights or on-time percentage (OTP) (e.g., 15-OTP metric). Researchers have shown that these flight-based metrics are poor proxies for passenger trip time performance. First, these metrics do not include the trip delays accrued by passengers rebooked because of canceled flights (which account for 40% of the overall passenger trip delays). Second, the metrics do not quantify the magnitude of the delay (only the likelihood) and thus fail to provide the consumer with a useful assessment of the impact of a delay (such as missed connections on next mode of transportation). A new consumer protection metric, expected value of passenger trip ...
Managing the Euro: European Central Bank Exchange Rate Policy Preferences

For a year following the launch of the euro, the European Central Bank (ECB) seemed indifferent to the currency's depreciation. Then the ECB changed to a policy position of trying to bolster the external value of the euro. This paper seeks to explain these patterns of positions on the ECB's external monetary policy. I argue that the ECB's policy on the exchange rate is a function of its commitment to domestic price stability in the euro zone. In other words, the ECB's concern with the euro's exchange rate centers solely on what that exchange rate can do to inflation. This focus on price stability is a function of the interests of the ECB in maintaining its own image of competence in European society.
Kumārila’s Buddhist

The pūrvapakṣa of the Śūnyavāda chapter of Kumārila’s Ślokavārttika (vv. 10-63) is the longest continuous statement of a Buddhist position in that work. Philosophically, this section is of considerable interest in that the arguments developed for the thesis that the form (ākāra) in cognition belongs to the cognition, not to an external object, are cleverly constructed. Historically, it is of interest in that it represents a stage of thinking about the two-fold nature of cognition and the provenance of the ākāra that is clearly more advanced than Dignāga but not quite as sophisticated as Dharmakīrti. In particular, although one may see an anticipation of Dharmakīrti’s famous sahopalambhaniyama argument in this text, it is not yet fully spelled out.
Food deprivation does not potentiate glucose taste reactivity responses of chronic decerebrate rats

The chronic supracollicular decerebrate (CD) rat fails to increase meal size in response to systemic/metabolic aspects of food deprivation. Here we asked whether or not deprivation increases immediate oral motor responding to taste stimuli (taste reactivity) in CD rats, as it does in neurologically intact controls. The responses of CD rats were evaluated as functions of glucose concentration and deprivation state, with taste reactivity responses recorded myographically during 15-s intraoral infusions and during 45-s post-infusion periods. Five glucose concentrations (0, 3.2, 6. 25, 12.5, 25%) were each presented three times during each test session. The rats were tested when not-deprived (i.e. receiving their full complement of gavage feedings), deprived (23.5 h) of food and water, and deprived of food but not water. The number of oral motor responses emitted increased monotonically with stimulus concentration; during oral infusions the increase was greatest over the lower half of the concentration range, whereas responding increased linearly with concentration in the post-infusion period. This CD response profile resembled that obtained previously with neurologically intact rats tested according to the same protocols. In contrast to results obtained in intact rats, deprivation did not influence the CD's response to glucose at any concentration or for any observation period. Although the caudal brainstem may receive and process information associated with deprivation state, neural interactions between forebrain and brainstem structures appear necessary for the behavioral expression of deprivation effects on meal size or, as we can now conclude, on immediate oral motor responses to taste stimuli.
Migración y estrés aculturativo: una perspectiva teórica sobre aspectos psicológicos y sociales presentes en los migrantes latinos en Estados Unidos

Since migration and the resulting acculturation process are such complex, multifaceted phe­ nomena, the aim of this article is to analyze the economic, social, political, and cultural factors involved. To achieve this, the author examines theoretically different empirical studies and papers related to the migratory experience. The article also describes the main reasons why Hispanic immigrants leave their countries of origin, as well as the main factors linked to the acculturation process and the acculturative stress immigrants experience during their stay in the United States.
Conditional tradeoffs between aging and organismal performance of Indy long-lived mutant flies

Alterations that extend the life span of animals and yeast typically involve decreases in metabolic rate, growth, physical activity, and/or early-life fecundity. This negative correlation between life span and the ability to assimilate and process energy, to move, grow, and reproduce, raises questions about the potential utility of life span extension. Tradeoffs between early-life fitness and longevity are central to theories of the evolution of aging, which suggests there is necessarily a price to be paid for reducing the rate of aging. It is not yet clear whether life span can be extended without undesirable effects on metabolism and fecundity. Here, we report that the long-lived Indy mutation in Drosophila causes a decrease in the slope of the mortality curve consistent with a slowing in the rate of aging without a concomitant reduction in resting metabolic rate, flight velocity, or age-specific fecundity under normal rearing conditions. However, Indy mutants on a decreased-calorie diet have reduced fecundity, suggesting that a tradeoff between longevity and this aspect of performance is conditional, i.e., the tradeoff can occur in a stressful environment while being absent in a more favorable environment. These results provide evidence that there do exist mechanisms, albeit conditional, that can extend life span without significant reduction in fecundity, metabolic rate, or locomotion.
Religiosity is an Important Part of Coping with Grief in Pregnancy After a Traumatic Second Trimester Loss

Women (n = 15) who were pregnant after a traumatic late pregnancy loss (termination because of fetal death or serious anomalies) completed psychometric screening tests and scales, including the Perinatal Grief Scale (PGS), the Impact of Event Scale (IES), the Duke Depression Inventory (DDI), the Generalized Anxiety Disorder-7 (GAD), and the Hoge Scale for Intrinsic Religiosity (IR). Despite a mean elapsed time since the prior loss of 27 (range, 7–47) months, half (7/15, 47%) of the combined groups had high levels of grief on the PGS. Multiple positive scores on psychometric tests were frequent: Sixty percent (9/15) had high scores on the PGS Active Grief subscale or on the IES. Forty percent (6/15) had a high score on the DDI, and 17% (3/15) on the GAD. IR scores significantly and negatively correlated with scores on the Despair subscale of the PGS. The results from this pilot study suggest that high levels of grief and PTS symptoms are significant problems for pregnant women who have suffered late loss of a wanted pregnancy. Religiosity may play an important part in maternal coping during these stressful pregnancies.
Sensor fusion at different levels of data abstraction

A unified information fusion, decision and control scheme is presented at different levels of data abstraction for multisensor-based robotic systems. It is based on the framework of Bayesian networks. Shannon's measure of mutual information and error-based measures are used in the decision of information sources.
Characteristics of VHF Capacitively Coupled Plasmas in a 300 mm Etch Chamber

Summary form only given. We have investigated the characteristics of VHF capacitively coupled plasmas produced in a modified applied materials chamber. The chamber had a 14-inch diameter upper electrode (source) that was driven at 10 to 160 MHz and a 300 mm diameter electrostatic chuck with a ceramic process kit that was driven at 13.56 MHz (bias). Diagnostics employed include RF diagnostics to measure the voltage and current, Bdot probes to measure the spatial magnetic fields, a microwave interferometer to measure the line-integrated electron density, a hairpin microwave resonator to measure the spatially resolved electron density, absorption spectroscopy to determine the argon metastable temperature and density, laser induced fluorescence (LIF) to determine the spatial distribution of the excited species, and spatially resolved optical emission. Scaling of the plasma parameters with frequency, power and pressure, and implications to energy deposition models will be discussed
Rational Choice and the Limits of Theoretical Generality

Claims that rational choice analysis represents a general theory of social processes raise questions not only about rational choice but about the very idea of theoretical generality. Logically, a t...
Brain Region-Specific Changes in N-Acylethanolamine Contents with Time of Day

The N-acylethanolamines (NAEs) exert important behavioral, physiological, and immunological effects through actions at cannabinoid and other receptors. We measured concentrations of three NAEs, the Km and Vmax for fatty acid amide hydrolysis (FAAH), FAAH protein and FAAH mRNA in prefrontal cortex, hippocampus, hypothalamus, amygdala, striatum, and cerebellum at 4 h intervals, starting at 03:00. Significant differences in N-arachidonylethanolamine contents among the times examined occur in the prefrontal cortex (PFC), hippocampus, hypothalamus, and striatum. N-Oleoylethanolamine concentrations exhibit large fluctuations over the day in the cerebellum, including a threefold decrease between 19:00 and 23:00. N-Palmitoylethanolamine and N-oleoylethanolamine were significantly, positively correlated in all regions examined except the hypothalamus. FAAH Km values are significantly affected by time of day in PFC, hippocampus and amygdala and FAAH Vmax values are significantly affected in PFC, hippocampus and cerebellum. However, correlational data indicate that FAAH does not play a primary role in the circadian regulation of the NAE concentrations. FAAH protein expression is not significantly different among the harvest times in any brain region examined. Concentrations of 2-arachidonoylglycerol are significantly affected by time of harvest in the striatum and cerebellum, but not in other brain regions. Together, these data indicate that the NAEs exhibit diverse patterns of change with time of day that are likely the result of alterations in biosynthesis, and support the hypothesis that N-arachidonylethanolamine is a tonic activator of cannabinoid receptor signaling. Concentrations of the endocannabinoid, anandamide (AEA) exhibit significant variability over the day that is brain region specific. It is our hypothesis that AEA is a tonic regulator of cannabinoid receptor activity in brain and that the changes in AEA content over the day reflect differences in AEA regulation of basal tone. The hypothesized patterns of tonic CB1 receptor activity in four brain regions are shown in this figure.
Influence of heating rate on the condensational instability

We determine by analysis and numerical simulation the effect that various heating rates have on the linear and nonlinear evolution of a typical plasma within a solar magnetic flux tube subject to the condensational instability. We first derive a dispersion relation for infinitesimal disturbances to a condensationally unstable fluid subject to heating rates which are functions of temperature and thermal pressure. This relation leads to an algebraic model for predicting solar flux tube stability in the longwavelength limit as a function of temperature. We find that linear stability depends strongly on the heating rate. We then present the results of numerical simulations of the nonlinear evolution of the condensational instability in a solar magnetic flux tube. Different heating rates lead to quite different nonlinear evolution, as evidenced by the behaviour of the global internal energy. Almost all of the heating rates that we consider produce saturation in bifurcated states, but at somewhat different temperatures and mass densities.
Effects of electric field gradient on an anti-plane crack in piezoelectric ceramics

An anti-plane, semi-infinite crack in polarized ceramics is analyzed using the theory of elastic dielectrics with electric field gradient. The effects of electric field gradient on electromechanical fields around the crack is examined.
An ACTH-producing small cell lung cancer expresses aberrant glucocorticoid receptor transcripts from a normal gene

ACTH production by non-pituitary tumors is generally not suppressible by exogenous glucocorticoid administration. We had postulated that defects in the glucocorticoid receptor (GR) signaling system might be responsible for this apparent glucocorticoid resistance and had previously demonstrated that DMS-79 cells, derived from an ectopic ACTH-producing tumor, express an abnormal GR mRNA. In this DMS-79 cell GR the sequence normally derived from exons 8 and 9 is replaced by sequence unmatched in the DNA databases. The protein encoded by this mRNA lacks the steroid-binding domain and does not function as a ligand-activated transcription factor. In the present work, we sought to identify the origin of the novel GR mRNA sequence. Southern blot analysis of DMS-79 genomic DNA showed no major structural alteration of the GR gene. Southern blotting of cosmid clones of the normal GR gene revealed that the novel DMS-79 GR mRNA sequence is derived from intron G, between exons 7 and 8. No splice site mutations were found in PCR-amplified DMS-79 DNA fragments surrounding the downstream splice junctions. Further sequencing indicated that the aberrant GR transcript appears to be generated by use of a consensus cleavage/polyadenylation signal found 3650 base pairs into the normal intron G. We conclude that abnormal GR pre-mRNA processing rather than a GR gene mutation confers glucocorticoid resistance on DMS-79 cells.
On the existence of random measure preserving bijections

Abstract This paper establishes the existence of an invariant probability measure on the set Π of measure-preserving bijections of the unit interval. In fact, the measure may be further restricted to be a Baire-measure. This result is compared with Aumann's (1967) and Aumann and Shapley's (1974) impossibility theorems.
A decade experience with infrainguinal revascularization in a dialysis-dependent patient population

Abstract Objective: Although previous series have reported outcomes of lower extremity (LE) revascularization in patients with end-stage renal disease, the issue of LE bypass for limb salvage in this group has not been resolved. We herein present the largest series to date of a 10-year single-institution experience with LE bypass in patients with dialysis dependence. Methods: With prospectively entered data from a university teaching hospital's vascular registry, we reviewed the records of all patients with dialysis dependence who underwent LE arterial bypass between January 1, 1990, and May 31, 1999. Results: A total of 146 consecutive patients (177 limbs) underwent infrainguinal revascularization, of whom nearly all (92%) had diabetes and tissue loss (91%). The in-hospital mortality rate was 3% (five patients). The rates for perioperative congestive heart failure, myocardial infarction, arrhythmia, and wound infection were 2%, 3%, 5%, and 10%, respectively. The actuarial graft primary and secondary patency rates at 1 and 3 years were 84% and 85%, and 64% and 68%, respectively. The limb salvage rates were 80% and 80% at 1 and 3 years. The 1-year and 3-year cumulative survival rates were 60% and 18%, respectively. At 5 years, survival was poor with only 5% of the entire cohort of 146 patients still alive. Multivariate logistic regression analysis at 6 months identified age (odds ratio, 0.96, 0.91) and number of years on dialysis (odds ratio, 0.79, 0.74) as significant (P
Delayed mortality in adult chickens exposed to 1 atmosphere oxygen.

Age dependence of resistance of chickens to 100 percent oxygen at one atm /OAP/, noting delayed mortality in adult birds
Daughters’ Maternal Grandsires in Sire Evaluation

Abstract First lactation records of 808,796 artificially sired cows in the Northeast United States were used to compare sire evaluations with and without maternal grandsires in the model. Maternal grandsires were identified on 55.7% of the records. Including maternal grandsire increased percent filled subclasses in absorbed best linear unbiased prediction equations by 43% (Guernseys) to 95% (Holsteins). Rank correlations between sire evaluations for the two models ranged from .91 (Ayrshires) to .97 (Holsteins). Product moment correlations ranged from .92 to .98. Holstein sires changed an average of 52 kg of milk. Negative assortative mating (good sires and poor maternal grandsires) was observed in the Guernsey and Brown Swiss breeds. Positive assortative mating (good sires and good maternal grandsires) occurred in the Ayrshires, Holsteins, and Jerseys. Including maternal grandsires of cows in the model is a step toward utilizing more genetic relationships in a practical sire evaluation system.
Interactive y-ӯ Diagrams On A Personal Computer

A computer program has been written which allows the user to draw a y-ӯ diagram on the computer screen. Based on the diagram data, the system prescription is calculated. The first order properties such as effective focal length, pupil size and pupil position are also determined. The program can modify a system by lens bending or thickening, and by conjugate and stop shifts. The software runs on IBM PCs and compatibles.
ICV administration of anti-NPY antisense oligonucleotide: effects on feeding behavior, body weight, peptide content and peptide release.

Neuropeptide-Y (NPY) is a potent stimulator of feeding, and chronic administration of the peptide has been shown to increase body weight. This study determined the chronic effects of repeated daily injections of an antisense phosphorothioate oligonucleotide complementary to the rat mRNA for NPY (aNPY) on food intake, feeding behavior and body weight change in rats. Five μg of the aNPY oligonucleotide in ten μl of vehicle or a missense control oligonucleotide were administered intracerebroventricularly (ICV) for seven consecutive days. Cumulative food intake, meal size and meal duration were significantly lowered in aNPY-treated animals. Body weight change of aNPY-injected animals was significantly lower than controls, and the effect was reversed after treatments ceased. A two-bottle taste aversion paradigm was employed to determine the behavioral specificity of the anorectic effect, and the phosphorothioate oligonucleotide was found not to be aversive at the dosage used. Following an additional five day injection period, animals were killed and paraventricular nuclei (PVN) were dissected. In vitro release and tissue content of NPY from this brain area were evaluated by heterologous radioimmunoassay. Content of NPY was unchanged in this brain area. Paradoxically, in vitro release of NPY was increased in aNPY-treated animals.
Amino acid requirements for growth of the rabbit blastocyst in vitro

Ten amino acids, namely, arginine, histidine, lysine, tryptophane, methionine, phenylalanine, leucine, valine, threonine and serine were indispensable for growth of rabbit blastocysts in vitro; others were nonessential. Of all the essential amino acids, arginine and lysine were required in relatively high concentrations, 10−2 M and 10−3 M, respectively, for optimum growth. Complete omission of the non-essential amino acids from the medium markedly reduced blastocyst growth. Interaction between serine and glycine demonstrated a partial sparing action on serine by glycine, similar to that observed between methionine and cysteine. The amino acid composition of a culture medium capable of providing continuous and consistent growth of rabbit blastocysts in vitro is described.
Unifying Themes in the Oeuvre of John M. Headley

The great variety of historical figures and themes found in the published works of John Headley since 1963 reveal a unity of themes and values. The numerous persons whom Headley studied all envisioned a humane universal order even as they moved from theoretical reflection to actual political implementation. His more recent work holds up the European legacy of human rights, democracy, and freedom that have become a Western gift and challenge to non-Western cultures.
Bifurcation analysis of pressure-drop oscillations and the Ledinegg instability

Abstract Pressure-drop oscillations and the Ledinegg instability are analyzed from the perspective of dynamical systems theory. An integral formulation is developed to model the two-phase flow system. Instability criteria independent of the actual two-phase flow model are derived for the two phenomena. It is shown that the pressure-drop oscillation limit-cycles occur after a super-critical Hopf bifurcation. In an extension of the analysis, an effort is made to clarify the mechanisms of the pressure-drop type oscillations and Ledinegg instability. The two phenomena are classified from the angle of bifurcation theory, and the differences are outlined.
Crosslinked Collagen Films Stiffen the Nucleus of Marrow Stromal Cells and Promote Osteogenesis

Commitment of stem cells to different lineages is regulated by many cues in the microenvironment, and pluripotent marrow stromal cells (MSCs) prove particularly sensitive to matrix mechanical cues. MSCs were cultured on nano-thin highly ordered collagen films in which we tune the mechanical properties with enzymatic crosslinking by transglutaminase while the films maintain the same nanostructure. Cells pull on the collagen films, and visibly deform the fibrils when not cross-linked, and cells cultured on cross-linked films initially respond by altering their morphology, acto-myosin organization and nuclear shape. Mechanically anisotropic, native collagen films promote strong polarization and orientation along the highly aligned fibrils, whereas cross-linked films cause cells to spread isotropically and stiffen their nucleus with increased lamin-A/C expression. The morphology on cross-linked films appears osteoblastic and the early osteogenic transcription factor RUNX2 and the later marker osteonectin are indeed upregulated in comparison to cells on pristine collagen films. On other hand stiffening the nucleus by Lamin-A overexpression enhances osteogenesis. We also found positive correlation between matrix and nucleus mechanics and that they have a synergistic effect on MSCs differentiation potential. The results demonstrate that stem cells and their nuclei are highly sensitive to the detailed nanomechanics of their matrix.
A mathematical model of two-trophic-level aquatic systems with two complementary nutrients

Abstract A model of phytoplankton, zooplankton, and two complementary nutrients, nitrogen and phosphorus, that simulates the dynamics of their interactions in lakes or oceans is presented. The paper studies a mathematical model, based on a modified Michaelis-Menten kinetics, for the phytoplankton uptake of the two nutrients, and a herbivore-density dependent grazing rate. Given the parameters of the system, we answer the basic questions about persistence, extinction, and limiting behavior of the microorganisms. The analytical studies demonstrate the role of the total system nutrients in governing system behavior and in turn in governing water quality control. Features of the model system include behavior determined solely by the total system nutrients, nitrogen and phosphorus. A conclusion robust for the model is the coupling of nitrogen and phosphorus cycles in more realistic dynamics that increase the effectiveness of water quality-control programs.
Natural Gas Seepage On The South Texas Shelf

An area of extensive gas seepage was found on the South Texas shelf. The seep area extends for a distance of about 25 mi on a transect out from the coast at latitude 26/sup 0/ 10'N. Water depths are in the 65-130 m range. During nine samplings in 1975-77, elevated near-bottom concentrations of methane (up to 500 nl/l.), ethane (0.6 nl/l.), and propane (0.5 nl/l.), compared with nearby surface and other near-bottom waters, were observed. Anomalous gaseous hydrocarbon levels were also observed in the interstitial waters at three stations sampled in the region. Ethane and propane concentrations were typically one order of magnitude higher in these sediments compared with typical South Texas shelf sediments. The C/sub 1/:(C/sub 2/ + C/sub 3/) ratios in the sediments were as low as 14:1, indicating that the seepage may be of a petrogenic origin and not from shallow biogenic (microbial) sources. Significantly higher percentages of hydrocarbonoclastic bacteria were observed in the seep area. These may be a direct result of hydrocarbon seepage.
Enhancing the attractiveness of the SDR

Abstract Despite significant growth in their use there has been no new allocation of SDRs since 1981. This paper describes recent improvements in the SDR's usefulness and explores ideas for further enhancement, in the expectation that an increase in the demand for SDRs would improve the prospects for further allocation. Wide use of the SDR as a unit of account and arrangements linking the IMF's official SDR with private ones should increase the demand for SDR to nominated users. Ideas examined include giving the SDR a constant real value, payment clearing arrangements linking official and private SDRs, and development of forward transactions.
Stress and Coping in Women Living with HIV: A Meta-Analytic Review

To examine effects between stressors and coping mechanisms on behavioral health outcomes a meta-analysis was conducted using forty empirical articles which sampled 7,602 adult women living with HIV/AIDS in the U.S. (M = 36.3 years). Three independent reviewers conducted searches in abstract databases from 1997 to present day. Articles reporting effect sizes amongst psychosocial stressors and coping mechanisms with indices of behavioral/mental health were selected. The meta-analyses revealed that in a time frame characterized by the widespread availability of anti-retroviral medication, poor mental health outcomes were predicted, in a similar manner, by psychosocial stress and HIV/AIDS symptomology. Significant effects were also observed with functional impairment, though to a lesser degree. Coping by avoidance and social isolation predicted more severe mental health outcomes. Spirituality and positive reappraisal predicted greater psychological adaptation than did social support seeking. Despite advancements in anti-retroviral treatment for women, HIV/AIDS symptoms and acute and/or chronic psychosocial stress pose the same threat to behavioral and mental health. In the face of these stressors, positive reframing appears to promote psychological adaptation in a way which may lead to positive health outcomes in women living with HIV/AIDS.
Continuous orthonormalization for multi-point problems for linear ordinary differential equations

The method of continuous orthonormalization is formulated for multi-point boundary value problems for linear ordinary differential equations. A representation of the solution is obtained in terms of solutions of well-defined initial value problems. The degrees of freedom in this representation are reduced at successive boundary points until the solution is completely known at the last boundary point. A modified back-integration then provides the solution over the whole interval. Some stiff and oscillatory three-point and periodic boundary value problems are solved numerically to illustrate the method.
Integrative Structure Determination of the Components of the Nuclear Pore Complex by X-Ray Crystallography, Small Angle X-Ray Scattering, Electron Microscopy, NMR, and Comparative Modeling

The Nuclear Pore Complex (NPC, ∼50 MDa) is the sole passageway for the transport of macromolecules across the nuclear envelope. The NPC plays a key role in numerous critical cellular processes such as transcription, and many of its components are implicated in human diseases such as cancer. Previous work (ref 1, 2) defined the relative positions of its 456 constituent proteins (nucleoporin or Nups), based on spatial restraints derived from biophysical, electron microscopy, and proteomic data. Further elucidation of the evolutionary origin, transport mechanism, and assembly of the NPC will require higher resolution information. As part of an effort to improve upon the resolution and accuracy of the NPC structure, we set out to determine the atomic structures of the NPC components. Because it proved difficult to determine the atomic structures of whole Nups by X-ray crystallography alone, we are relying on multiple datasets that are combined computationally by our Integrative Modeling Platform (IMP) package (http://salilab.org/imp). In particular, we developed an integrative modeling approach that benefits from crystallographic structures of fragments of the protein or its homologs, Solution Small Angle X-ray Scattering (SAXS) profiles of the protein and its fragments (ref 3), NMR, and negative stain Electron Microscopy (EM) micrographs of the protein. Each dataset is converted into a set of spatial restraints on the protein structure, followed by finding a model that satisfies the restraints as well as possible using a Monte Carlo / molecular dynamics optimization procedure. The approach will be illustrated by its application to yeast Nup133.1. Alber et al., Nature 450, 683-694 (2007).2. Alber et al., Nature 450, 695-701 (2007).3. Forster et al., J Mol Biol 382 (4), 1089-1106 (2008).
Modeling and design of planar parallel-connection flexible hinges for in- and out-of-plane mechanism applications

Abstract The paper studies the planar parallel-connection, small-deformation flexible hinge chains formed of serially-coupled individual segments with variable cross-sections. It introduces the concept of virtual flexible hinge that is quasi-statically equivalent to the actual parallel-hinge configuration. General compliance and stiffness matrices are formulated for the virtual hinge under in-plane and out-of-plane loads by combining the transformed compliances of the individual hinge segments. Two classes are specifically analyzed: one comprises geometrically parallel, straight-axis hinge designs and the other includes concentric, circular-axis hinge configurations. From each class, particular designs with identical and transversely symmetric hinges of right circularly corner-filleted geometry are further investigated. Specifically, the behavior of parallelogram mechanisms with straight-axis hinges and of stage devices with circular-axis hinges is analyzed. Their elastic responses are validated by finite element analysis and their stiffnesses are subsequently studied in terms of offset geometric parameters.
Vascular α-adrenergic blocking properties of quinidine

The specificity of the alpha-adrenergic vascular blockade by quinidine was tested in the intact dog, in rabbit isolated aortic strips, and in rats under ganglionic blockade. Quinidine did not affect the pressor response of angiotensin II in dogs, the contractile response of histamine nor angiotensin II in aortic strips, nor the dose-pressor response curve of the alpha-agonist, B-HT 933 in the rat. However, the pressor effect of adrenaline and noradrenaline (NA) were significantly reduced in dogs, and the dose-response curves to NA in aortic strips and to the alpha-agonist, phenylephrine in rats was shifted to the right in a parallel manner by quinidine. In the rat, quinidine is at least 14 times more potent in antagonizing the vasopressor effect of an alpha 1-vs. and alpha 2-adrenoceptor agonist.
Numerical Simulation of 3D EM Borehole Measurements Using an hp-Adaptive Goal-Oriented Finite Element Formulation

We describe two different algorithms for automatic generation (without any user interaction) of optimal goal-oriented grids within a 3D higher-order Finite Element (FE) package, in context of simulation of electromagnetic borehole resistivity measurements for the assessment of rock formation properties. The first algorithm is based on transferring a two-dimensional optimal grid obtained from a 2D self-adaptive method. The resulting grid enables fast simulations (few seconds per logging position), although the accuracy of the final 3D results may be compromised in the case of highly deviated wells when combined with rapid spatial variations in electrical conductivity. For those cases, we developed a second algorithm based on a fully automatic three-dimensional goal-oriented strategy that, although it is considerably slower, it guarantees accurate results. A proper combination of both algorithms enables highly accurate numerical simulations of a variety of 3D resistivity logging measurements at different frequencies. This is illustrated in the manuscript with a Through Casing Resistivity (TCR) model problem. Numerical results corresponding to laterolog measurements indicate that differential voltage measurements remain sensitive to the 3D effects of various 3D sources and receivers only in deviated wells. In vertical wells, measurements are insensitive to the 3D effects of the sources and receivers. Thus, the resulting 3D combined effect (due to the use of 3D sources and receivers and deviation of the well) is different from the superposition of individual 3D effects.
Light Ion Sources for ICF

PBFA II, Sandia National Laboratories' (SNLA) advanced light-ion accelerator [1] (now under construction), will deliver a 30-MV, 5 MA lithium ion beam to an Inertial Confinement Fusion (ICF) target. Although most ICF experiments have been performed with proton beams, lithium ions were selected for PBFA II for several reasons. The use of lithium enables a large anode-cathode spacing, resulting in less impedance change during the pulse. Lithium ions have less magnetic deflection in the diode, so they can be focused for a longer period of time. Also, since the ionization potential of Li+ is low, while that of L++ is very large, a Li+ source should be achievable without significant contamination from Li++ Ions heavier than Li+ would require operating voltages greater than 30 MV, or the ions would have to be accelerated in a multiple charged state. The selection of the lithium option for PBFA II has made the development of a suitable lithium source one of the highest priority areas in the light-ion ICF program. Following that decision in the fall of 1983, SNLA organized a comprehensive ion source program to develop an optimum lithium source for PBFA II and to understand near-term sources.
An efficient frequency-domain algorithm for discrete orthogonal basis restoration

Discrete orthogonal basis restoration (DOBR) is a robust method for the inverse solution of linear systems of the type [A][o]=(i), where [A] may be either shift variant or invariant. Presented in this work is the derivation of a frequency-domain DOBR algorithm that significantly improves computational efficiency. Substantial reductions in the number of arithmetic operations are possible when system stationarity allows the use of precalculated DOBR characteristic vector sets, and sampling of the signal is rapid relative to the highest frequency of interest. More modest improvements in computational efficiency (10%-40%) are obtained when the entire DOBR algorithm must be executed. In addition to reducing the number of floating-point operations and storage requirements, the frequency-domain DOBR algorithm lessens the deleterious effects of perturbations in [A] on the inverse solution.
Half-life and spin of 60 Mn g

A value of 0.28{+-}0.02 s has been deduced for the half-life of the ground state of {sup 60}Mn, in sharp contrast to the previously adopted value of 51{+-}6 s. Access to the low-spin {sup 60}Mn ground state was accomplished via {beta} decay of the 0{sup +} {sup 60}Cr parent nuclide. New low-energy states in {sup 60}Mn have been identified from {beta}-delayed {gamma}-ray spectroscopy. The new, shorter half-life of {sup 60}Mn{sup g} is not suggestive of isospin-forbidden {beta} decay, and new spin and parity assignments of 1{sup +} and 4{sup +} have been adopted for the ground and isomeric {beta}-decaying states, respectively, of {sup 60}Mn.
A new method for one-dimensional linear feature transformations

Abstract We propose a method for finding a linear transformation of an initial pattern space into a one-dimensional new space, which optimizes the L2 distance between density functions. We use an orthogonal expansion with Hermite functions to compute the criterion; we discuss both the truncation and the statistical variation error for this expansion. To avoid false local optima caused by sample variation, we choose the starting point with a coarse step optimization method. Experimental results with two-class and multi-class, both unimodal and multimodal, are presented.
The propagation of parametric uncertainty via polytopes

We consider the discrete dynamical system x(k+1)= A(k)x(k) with n2independently varying uncertainties in the entries of A (\cdot) . Although the set of possible states X(k) at time k is not necessarily convex, we show that the convex hull of this set can be recursively propagated forward in time.
Evidence for a Dimethyl Sulfide Precursor in Milk

Abstract The dimethyl sulfide (Me 2 S) content of milk was increased by heating which indicated the presence of a heat labile Me 2 S precursor compound. A quantitative gas chromatographic method was employed to demonstrate that the precursor remained in the skimmilk fraction. A concentration procedure, involving dialysis and lyophilization, yielded sufficient compound for characterization. The precursor was identified as an S-methyl-methionine sulfonium salt on the basis of its thin-layer chromatographic mobility and the heat instability of the compound. Heating of samples caused the disappearance of the compound with a subsequent increase in the content of homoserine and Me 2 S.
Prevalence of Pathogenic Escherichia coli in Recreational Waters

The prevalence of pathogenic Escherichia coli in recreational waters has rarely been quantified. Standard enumerative methods do not identify these pathogens, and thus may not accurately assess the health risk associated with recreational water. A collection of E. coli isolated from bathing waters and adjacent drainage ditches of Maumee Bay State Park (MBSP) on the southwest shore of Lake Erie was examined for the presence of virulence genes characteristic of enterohemorrhagic (EHEC), enteropathogenic (EPEC), and enterotoxigenic (ETEC) E. coli pathogens. The collection, 472 isolates, was screened by DNA-DNA hybridization using gene fragments of heat-labile toxin (lta, ETEC), heat-stable toxin (sta, ETEC), intimin (eaeA, EHEC, and EPEC) and enterohemolysin (hlyA, EHEC). Hybridization results were confirmed by polymerase chain reaction. Four isolates were shown to carry eaeA. The results indicate that E. coli containing virulence genes do exist as a fraction of the E. coli population at MBSP.