cssi/SciSciGPT-SciSciNet huggingface dataset:
ROTATION AND TURBULENCE OF THE HOT INTRACLUSTER MEDIUM IN GALAXY CLUSTERS

Cosmological simulations of galaxy clusters typically find that the weight of a cluster at a given radius is not balanced entirely by the thermal gas pressure of the hot intracluster medium (ICM), with theoretical studies emphasizing the role of random turbulent motions to provide the necessary additional pressure support. Using a set of high-resolution, hydrodynamical simulations of galaxy clusters that include radiative cooling and star formation and are formed in a cold dark matter (CDM) universe, we find instead that in the most relaxed clusters rotational support exceeds that from random turbulent motions for radii 0.1-0.5 r 500, while at larger radii, out to 0.8 r 500, they remain comparable. We also find that the X-ray images of the ICM flatten prominently over a wide radial range, 0.1-0.4 r 500. When compared with the average ellipticity profile of the observed X-ray images computed for nine relaxed nearby clusters, we find that the observed clusters are much rounder than the relaxed CDM clusters within ≈0.4 r 500. Moreover, while the observed clusters display an average ellipticity profile that does not vary significantly with radius, the ellipticity of the relaxed CDM clusters declines markedly with increasing radius, suggesting that the ICM of the observed clusters rotates less rapidly than that of the relaxed CDM clusters out to ≈0.6 r 500. When these results are compared with those obtained from a simulation without radiative cooling, we find a cluster ellipticity profile in much better agreement with the observations, implying that overcooling has a substantial impact on the gasdynamics and morphology out to larger radii than previously recognized. It also suggests that the 10-20% systematic errors from nonthermal gas pressure support reported for simulated cluster masses, obtained from fitting simulated X-ray data over large radial ranges within r 500, may need to be revised downward. These results demonstrate the utility of X-ray ellipticity profiles as a probe of ICM rotation and overcooling which should be used to constrain future cosmological cluster simulations.
Modeling flooding extent from Hurricane Floyd in the coastal plains of North Carolina

In this article two modeling approaches were developed based on the use of US Geological Survey digital elevation model (DEM) data. These models were utilized to delineate the extent of flooding induced by precipitation from Hurricane Floyd in a portion of Pitt County, North Carolina. The patterns of flood extent derived from the two models were compared to the extent of flooding indicated on a digital aerial photograph taken two days after peak flood levels had been reached. In addition, floodplain boundaries based on Federal Emergency Management Agency Q3 maps were compared to the extent of flooding on the aerial photo. Actual emergency response operations undertaken through the Pitt County Emergency Operations Center during the flood event are described, and are used to provide a context for evaluating the potential utility of these models. The flood extents produced by the modeling methods performed well at representing the actual extent of the flooding.
Optimization of fetal oxygenation.

The respiratory gases, oxygen (02) and carbon dioxide (CO2), cross the human placenta in the same manner as they traverse the alveolar-capillary membrane, ~-a though it appears that more shunting occurs in the placenta than in the normal lung. Oxygenation of the fetus, however, is enhanced by certain maternal and fetal physiologic characteristics. Maternal influences are twofold: 1. Respiratory: the pregnancy-induced increase in tidal volume combined with the decrease in functional residual capacity leads to a reduction in CO2 [mean PaCO2 in 79 gravidae 31.9_l.8mmHg] and a small elevation in 02 [mean PaO2 in 70 gravidae 106.1 +7.7 mmHg] . 4 2. Hematologic: the pregnancy-induced increase in 2,3-diphosphoglycerate (2,3-DPG) shifts the oxyhemoglobin-dissociation curve to the right, 5 thus decreasing affinity (i.e., augmenting release) of O1 from the hemoglobin molecule. 6 Fetal characteristics are threefold: 1. The amount of hemoglobin is increased to 16-17 g/dl (vs 11-12 g/dl in the mother). 1'7
An evaluation of sustainable agriculture training in North Carolina

ABSTRACT In fall 1996, an evaluation of the impact of the SARE Chapter 3 (Professional Development Program) training in North Carolina was undertaken. The evaluation reviewed each of the objectives and outcomes of the North Carolina sustainable agriculture Strategic Plan. The evaluation determined that most of the objectives had been achieved and that it would be worthwhile to develop a new Strategic Plan for sustainable agriculture training. A new plan for 1998–2003 is now developed by the Sustainable Agriculture Task Force based on the evaluation report.
Myelin galactolipids: Mediators of axon-glial interactions?

The precise alignment of myelin segments along the length of the axon is essential for the saltatory propagation of an electrical impulse. Furthermore, node of Ranvier formation and function are dependent on the proper interactions between myelinating glial cells and the axon. Nevertheless, the molecules that regulate the placement and association of myelinating cells with axons remain largely unidentified. Recently, however, the analysis of mutant mice incapable of synthesizing the galactolipids of myelin has revealed defects in these processes. The galactolipid-deficient mice display alterations in the spacing of internodal segments along the axon: large unmyelinated gaps are common and overlapping myelin segments are observed. Moreover, the normal tight association between the lateral loops of the myelinating cell and the axonal membrane at the paranode region is also disrupted in these animals. Strikingly, there is a complete absence of transverse bands at the axon-glial junction, with the lateral loops frequently turning away from the axon. These data indicate that the galactolipids play an essential role in axon-glial interactions and node of Ranvier formation.
Consolidation Of Plasma-Sprayed Coatings By Laser Remelting

Plasma-sprayed coatings of corrosion and wear resisting alloys were laser surface melted, with the objective of densifying them and improving their adhesion to the substrate materials. Corrosion resisting coatings of titanium and of 316L stainless steel on steel substrates were remelted with good results. After laser processing, these initially porous coatings were fully dense and exhibited good surface quality. Results with wear resisting coatings were disappointing beause the hard wear resisting phases crack under the tensile stresses developed during cooling. Results are discussed in terms of the effects of the initial coating properties, the laser beam parameters, and other processing variables such as processing atmosphere and sample translation rates.© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Workers' Rights Provisions in Fast Track Authority, 1974-2007: An Historical Perspective and Current Analysis

This article examines the trajectory of workers' rights provisions in "fast track" authority legislation allowing the U.S. president to negotiate free trade agreements that Congress can only approve or reject, not amend. I begin my analysis with the Trade Act of 1974 and continue through the expiration of fast track authority in 1994. Against this backdrop, I critique the workers' rights negotiating objectives and priorities in the Bipartisan Trade Promotion Authority Act of 2002 (TPA). Relying on TPA's confused legislative history and basic rules of statutory interpretation, the article seeks to interpret TPA's workers' rights provisions. It concludes by examining the practical implications of TPA's workers' rights negotiating objectives and priorities, as currently applied, by assessing the workers' rights provisions in the trade accords concluded under TPA. Ultimately, I find that, despite pronouncements to the contrary, TPA is a step backward from the Trade Act of 1974, which instructed U.S. trade negotiators to ensure that "the global trading system, as governed by GATT, included an enforceable requirement that countries adhere to international fair labor standards."
Serum Medroxyprogesterone Acetate (MPA) Concentrations and Ovarian Function Following Intramuscular Injection of Depo-MPA

A sensitive radioimmunoassay measuring serum medroxyprogesterone acetate (MPA) has been developed in order to measure and correlate serum MPA concentrations and ovarian function in women following im administration of depo-MPA (DMPA), employing goat anti-MPA-3-(O-carboxymethyl) oxime-bovine serum albumin and MPA-3-(O-carboxymethyl) imino-125I-iodohistamine. In the 3 women studied, im injection of 150 mg of DMPA yielded brief initial serum MPA concentrations ranging from 1.5 to 3 ng/ml for a few days. Serum MPA concentrations gradually declined and remained relatively constant at about 1 ng/ml for 2 to 3 months, declined gradually thereafter reaching 0.2 ng/ml during the 6th month and became undetectable (<0.02 ng/ml) about 7½ to 9 months following administration. Serum estradiol remained at early to midfollicular phase levels for 4 to 6 months after DMPA injection and rose to preovulatory levels when serum MPA levels fell below 0.5 to 0.25 ng/ml. Ovulation, however, as evidenced by serum progesterone conc...
Design as a minority discipline in a software company: toward requirements for a community of practice

This paper provides a description of designers' work practices in a software company. We describe a participatory analysis of the diversity of working relations and roles of designers of IBM's Lotus software products. Designers are an example of a minority discipline - that is, a discipline whose members are often isolated in their work teams among coworkers with different training, backgrounds, and career paths. We explore differences between the practices of designers of Lotus software products and the published reports of design practices in group settings
Error propagation fuzzy control system

Abstract A concept of a fuzzy control system that adjusts itself upon the error propagation between the real system and the model is introduced. Different possible error outcomes are defined, namely, right (left) error, right (left) missed error, rule lost error, symmetry lost error, right (left) shift error, and nonresponsive error. An application to the truck backer-upper control problem is presented to corroborate the theory and demonstrate the utility of the approach to fuzzy control.
Examining the Psychosocial Functioning and Characteristics of Incarcerated Girls with a Substance Use Disorder

The purpose of this study was to identify the psychosocial characteristics of incarcerated girls with a substance use disorder. Profile analysis, the repeated measures extension of multivariate analysis of variance, was conducted to compare a state-based sample of incarcerated girls with (n = 140) and without (n = 63) a substance use disorder across multiple subscales of the Multidimensional Adolescent Assessment Scale. Girls with a substance use disorder had higher levels of problem severity. They were more likely to have problems related to alcohol use, drug use, aggression, and cognition. Incarcerated girls with a substance use disorder may benefit from intense interventions that focus on cognitive restructuring or cognitive recovery, and interventions that promote coping and stress management skills.
Democratic commitments are not always credible: Abortion and German reunification

Can states make credible commitments to respect concessions they make as part of national reunification agreements? German leaders negotiating reunification in 1990 had to reconcile West Germany’s more restrictive abortion policy with East Germany’s more permissive one, and agreed in 1990 to a compromise that seemed to preserve first-trimester abortion on demand in the Eastern states. By 1993, however, that compromise had been undone and the formerly West German policy prevailed throughout the country. This history challenges the theory that commitments made by democratic regimes are credible, especially since there were a number of international and domestic factors present in this case that other scholars have identified as enhancing credibility. We investigate the trajectory of unification-era German abortion policy and make two arguments: the decision by West German leaders to undo their earlier concessions was conscious rather than accidental, and despite Western attempts to reach a compromise that Easterners would see as credible the prevailing view in the East during the negotiations was that the Western commitment was uncertain at best. We conclude with some broader speculation about reunification, and suggest that promises made by a larger partner during negotiations over national reunification have inherent credibility problems that democratic institutions cannot by themselves solve. This implies that future reunifications, for example between North and South Korea or China and Taiwan, may be even more difficult to negotiate than currently recognized.
Loading and maintenance doses of digoxin in patients with normal renal function and those with severely impaired renal function.

T HE clinician may find the equations and terminology in this report confusing and difficult to follow. However, pharinacokinetic theory is of little use unless those familiar with the theory show how application of the theory is of practical importance. This paper is an attempt to do so with a drug that has presented many problems with respect to dosing and toxicity. It is really not important that the clinician completely understand how the results were calculated; it is important for him or her to remember the results for each drug for which the equations were applied. The arguments are presented in the text, and the equations in the Appendix, so that those familiar with pharmacokinetic theory can apply them to other drugs and produce still more practical information for the busy clinician. The principal role of the clinician, with respect to the aspect of medicine discussed in this report, is to determine the relationship between clinical effect and dose of a drug. The principal roles of the pharmaco-
Mass transfer in graded microstructure solid oxide fuel cell electrodes

A computational model is presented in which performance of a solid oxide fuel cell with functionally graded electrodes can be predicted. The model calculates operational cell voltages at varying electrode porosity and operational parameters, accounting for losses from mass transport through the porous electrodes, ohmic losses from current flow through the electrodes and electrolyte, and activation polarization. Specifically the physical phenomena that occur when the electrode is designed with a change in microstructure along its thickness are studied. Cell polarizations are investigated to find arrangements for which the minimal polarization occurs. Both diluted hydrogen fuel and partially reformed methane streams with internal reforming are investigated. It is concluded that performance benefits are seen when the electrodes are given an increase in porosity near the electrolyte interface for certain fuels and with satisfactory material properties. Enhanced reformation is observed in high tortuosity structures due to increased gas residence time within the electrode.
Population growth in planaria Dugesia tigrina (gerard). Regulation by the absolute number in the population.

Planaria reproduce by transverse fission. Isolated worms increase in number exponentially, while social animals at the same density are inhibited in terms of numerical increase, but over a 25 day period undergo a larger increase in mass. Isolated posterior fission products reproduce faster than isolated anterior fission products. Regulation of population growth is independent of density over a 16-fold range and regulatory factors cannot be demonstrated in the medium. Regulation of population growth depends on direct contact between animals. Fission period varies from individual to individual and from period to period for a given individual. Doubling time is related to the absolute number of individuals comprising the population as follows: PN = (PM · N)/(K + N), where PN is the doubling period of a population of N individuals, PM is the doubling time of an infinitely large population, N is the number of individuals in the population, and K is the number of individuals in a population the period of which is one-half PM. At 22°–24°C PM is estimated to be 43.3 days and K is 1.87 individuals. A model system assumes that inhibitor flows through the population from animal to animal from the slowest to the fastest animal in the population thus acting to synchronize population increase as well as to determine the rate of population growth. A possible source of the inhibitor is discussed.
Nicotinic modulation of GABAergic synaptic transmission in the spinal cord dorsal horn.

Abstract While the mechanisms underlying nicotinic acetylcholine receptor (nAChR)-mediated analgesia remain unresolved, one process that is almost certainly involved is the recently-described nicotinic enhancement of inhibitory synaptic transmission in the spinal cord dorsal horn. Despite these observations, the prototypical nicotinic analgesic (epibatidine) has not yet been shown to modulate inhibitory transmission in the spinal cord. Furthermore, while nAChRs have been implicated in short-term modulation, no studies have investigated the role of nAChRs in the modulation of long-term synaptic plasticity of inhibitory transmission in dorsal horn. Whole-cell patch clamp recordings from dorsal horn neurons of neonatal rat spinal cord slices were therefore conducted to investigate the short- and long-term effects of nicotinic agonists on GABAergic transmission. GABAergic synaptic transmission was enhanced in 86% of neurons during applications of 1 μM nicotine (mean increased spontaneous GABAergic inhibitory postsynaptic current (sIPSC) frequency was ∼500% of baseline). Epibatidine (100 nM) induced an increase to an average of ∼3000% of baseline, and this effect was concentration dependent (EC 50 = 43 nM). Nicotinic enhancement was inhibited by mecamylamine and DHβE, suggesting an important role for non-α7 nAChRs. Tetrodotoxin (TTX) did not alter the prevalence or magnitude of the effect of nicotine, but the responses had a shorter duration. Nicotine did not alter evoked GABAergic IPSC amplitude, yet the long-term depression (LTD) induced by strong stimulation of inhibitory inputs was reduced when paired with nicotine. These results provide support for a mechanism of nicotinic analgesia dependent on both short and long-term modulation of GABAergic synaptic transmission in the spinal cord dorsal horn.
Infrastructure and productivity: An extension to private infrastructure and it productivity

Abstract This paper incorporates both public and private infrastructure within the framework of a nonlinear production function. The theoretical model specifies a technological growth rate as a nonlinear function of government infrastructure and private infrastructure generated by the information sector of the economy—cable, wireless stations, satellites, internet facilities, broadcasting, etc. The time trend is included to capture the effect of all other variables. The empirical estimates generated by the model imply increasing returns to scale for the US economy in the last few years. The evaluation of the growth accounting equation implies that information technology was the largest contributing component to growth during the expansion of the 1990s.
On the role of the NAO in the recent northeastern Atlantic Arctic warming

[1] Studies such as those by Zhang et al. [1998] and Peterson et al. [2003] suggest that the northeastern Atlantic Arctic warmed in the early 1990s and that regional sea level pressure (SLP) variations and the NAO may be responsible. Sea surface temperature changes in Fram Strait and the Barents Sea depend, respectively, on SLP variations over the Barents Sea and Norwegian Sea. Since winter 1972, SLP over the Barents and Norwegian Seas has been unusually low during NAO+ winters. Little pressure field change occurred during NAO- winters or around the Denmark Strait, the normal location of the Icelandic Low. Simultaneously, the NAO+ mode became highly persistent on a month-to-month basis throughout the NAO+ winters and ultimately throughout all seasons during a multiyear episode in which the Arctic reached peak warming. A similar NAO+ persistence episode is shown to have occurred from 1920–1925, during another notable Arctic warming event.
Phospholipid metabolism in mitochondria and microsomes of rabbit liver during development

Abstract The protein, total phospholipid, phosphatidyl inositol, sphingomyelin, phosphatidyl choline, phosphatidyl serine, and phosphatidyl ethanolamine concentrations of mitochondria and microsomes have been determined m the liver of −12, −9, 0, +2, +9, and +14-day-old rabbits. The pattern of growth and development of the liver and liver mitochondria and microsomes was demonstrated by increased wet weight of the liver, by increased mitochondrial and microsomal protein concentration per whole tissue, and by increased mitochondrial and microsomal phospholipid phosphorus per whole tissue. The protein concentration per g of wet tissue was observed to increase in both mitochondria and microsomes after birth. The concentration of total and individual phospholipid phosphorus per mg of mitochondrial protein does not change during development and would suggest that the pattern of mitochondrial phospholipids has been established prior to the development interval studied (−12 to +14 days). This observation would suggest that the duplicating machinery for the phospholipids of membranes of rabbit-liver mitochondria has already been developed 12 days before birth. However, this is not true for the microsomes. The concentration of phospholipid phosphorus per mg of microsomal protein showed an increase in the amount of total phospholipid and phosphatidyl choline before birth and phosphatidyl ethanolamine and phosphatidyl inositol after birth. The incorporation of radioactive phosphorus into the phospholipid fractions of mitochondria and microsomes seemed to indicate a relatively constant rate of synthesis during development.
Hepatocellular carcinoma in young, mentally retarded HBsAg carriers without cirrhosis

In a Californian institution for the mentally retarded, surveillance by autopsy of all deaths (n = 138) identified three cases of hepatocellular carcinoma. Hepatocellular carcinoma cases occurred in young (mean age = 26 years) male carriers of HBsAg and were not associated with cirrhosis. They were of the nonfibrolamellar oncocytic type and were rapidly fatal. Hepatocellular carcinoma incidence in HBsAg carriers was estimated to be 246 times greater than United States males.
Thermal Hydraulics of Wellbores and Surface Lines During Steam/Hot Water Injection—Part I: Theoretical Model

A mathematical model is proposed for analyzing the thermal hydraulic behavior of wellbores and surface lines. The model discusses two-phase pressure drop and heat transfer for a variety of practical wellbore boundary conditions and includes theoretical formulations for calculating effects of geothermal gradient, transient heat flow to the surroundings of the wellbore, and radiation and convection heat transfer in the annulus. The model has been applied to evaluate the effects of insulation thickness, injection rate and injection time on steam temperature and quality. Some interesting performance behaviors are noted. The predictions of the model are compared with the results of other models and a field case.
The Effect of Dietary Copper Sulfate on Infectious Proventriculitis

Abstract Oral inoculation of day-old broiler chicks with a crude homogenate of affected proventricular tissue, or the same homogenate filtered through a .2 μm filter caused proventricular lesions similar to those responsible for carcass contamination of broilers at processing. Dietary copper sulfate (CUS) has also been shown to produce similar lesions. In this study, we investigated the interaction between crude proventriculus homogenate or filtered proventriculus homogenate and 1 g/kg CUS added to a standard chicken diet. Cobb × Cobb female broiler chicks were distributed into six groups with four replicate battery pens per group. Birds were fed either a standard broiler starter diet or the same diet with 1 g/kg CUS. Each dietary treatment was inoculated per os with 1 mL of either sterile saline, unfiltered homogenate, or filtered homogenate. Both crude and filtered homogenates had a much stronger affect on proventriculus score than did Cu by itself, resulting in no interaction between either homogenate or filtrate and CUS. There was a significant and possibly antagonistic interaction on proventriculus relative weights in the CUS by filtrate group during Week 1 and a synergistic interaction in the CUS by homogenate group during Week 4. Body weights were decreased in birds fed homogenate or CUS, but not in birds fed filtrate. There was a protective effect shown by filtrate on body weight of birds fed both filtrate and CUS only during Week 1. There was a synergistic decrease in body weight of birds fed homogenate and CUS during Week 2. Overall feed conversion efficiency was significantly decreased in the homogenate treatment (P = .04) and decreased in the birds fed CUS (P = .1). There was a (4.2 vs 2.3) (P = .1) decrease in feed conversion efficiency in birds fed both homogenate and CUS. Natural exposure to low levels of the infectious agent present in the homogenates may interact with excess dietary CUS, resulting in increased proventriculus size and decrease in body weight and feed conversion efficiency.
The Ventricular Gradient Revisited: Relation to the Area Under the Action Potential

The ventricular gradient G is shown to be related to the area ?under the cellular action potential. For ac-coupled amplifiers, ? is calculated by taking the resting potential for each cell to be zero. The contribution to G for a small volume of the heart is then proportional to the gradient of ?weighted by the transfer impedance or lead field Z. An expression is developed which relates the secondary T wave to the QRS complex and the shape of the action potential. This expression is evidently equivalent to a procedure originally proposed by Abildskov et al. [6].
Failure to capitalize on sharing good news with romantic partners: Exploring positivity deficits of socially anxious people with self-reports, partner-reports, and behavioral observations

Extending prior work on social anxiety and positivity deficits, we examined whether individual differences in social anxiety alter the ability to share and respond to the good news of romantic partners (i.e., capitalization support) and how this influences romantic relationship satisfaction and commitment. In this study of 174 heterosexual couples (average age of 21.5 with 58.3% identifying as Caucasian), greater social anxiety was associated with the provision and receipt of less supportive responses to shared positive events as measured by trait questionnaires, partner reports, and behavioral observations in the laboratory. In longitudinal analyses, individuals in romantic relationships with socially anxious partners who experienced inadequate capitalization support were more likely to terminate their relationship and report a decline in relationship quality six months later. As evidence of construct specificity, social anxiety effects were independent of depressive symptoms. Taken together, social anxiety influenced a person's ability to receive and provide support for shared positive events; these deficits had adverse romantic consequences. Researchers and clinicians may better understand social anxiety by exploring a wider range of interpersonal contexts and positive constructs. The addition of capitalization support to the social anxiety literature offers new insights into interpersonal approaches and treatments.
Cradle-to-gate life cycle impacts of redwood forest resource harvesting in northern California

Abstract The first life cycle impact assessment for redwood ( Sequoia sempervirens ) forest management activities (i.e. a cradle-to-sawmill gate input) including the growing, harvesting, and hauling of redwood sawlogs to a sawmill was completed. In the stump-to-truck timber harvesting analysis, primary transport activities such as skidding and yarding consumed the largest amount of fuel and consequently generated the greatest environmental impacts (50% of the total) compared with the other harvesting stages (felling, processing, and loading). Hauling sawlogs to the sawmill was also a major contributor to total greenhouse gas emissions, representing 20% of total emissions. The most efficient harvest method in terms of fuel consumption per m 3 of wood harvested was the manual ground-based system used in even-aged silvicultural operations, followed by the skyline harvesting methods. Relative to even-aged silvicultural systems, uneven-aged systems, often prescribed to meet environmental goals such as maintaining biodiversity and protecting wildlife habitats, used 20% more fuel per m 3 of redwood sawlogs harvested. This was because uneven-aged systems required an increased number of entries to harvest the same amount of wood as even-aged systems. The cradle-to-gate GHG emissions from redwood forest management activities including growing, harvesting and hauling the logs represent only 14% (17.13 kg CO 2 e/m 3 ) of the total GHG emissions (i.e. cradle-to-grave) associated with redwood decking lumber. The study results showed substantial differences in environmental impacts for the various harvesting operations and silvicultural systems for redwood forest management and operations. Therefore, the life cycle impact assessment results for the various redwood harvesting and silvicultural systems should be carefully considered when evaluating environmental performance of forest management activities along with other objectives.
Electrodiagnostic studies in the management and prognosis of neuromuscular disorders

Prognosis remains a neglected aspect of modern medical care and research, behind diagnosis and treatment. The very term “electrodiagnosis” implies as much. Despite this, much has been published regarding the use and benefit of electrodiagnostic techniques in assessing prognosis and assisting in management of patients after the diagnosis has been established. This information is often hidden or otherwise not emphasized. This review summarizes the literature regarding the use of such techniques for prognosis and management of disorders of lower motor neurons, peripheral nerves, neuromuscular transmission, and muscle. Muscle Nerve 29: 165–190, 2004
Structural economics of the U.S. rail freight industry: Concepts, evidence, and merger policy implications

Abstract The structure of the U.S. rail freight industry has dramatically changed in the past decade due to bankruptcies, mergers and deregulation. Historically, dozens of major railroads covered limited geographic areas, so that most shipments required connections of two or more carriers. There was considerable evidence that most carriers were operating at less than efficient scale. This article presents the basic concepts relating firm size to production costs and reviews empirical studies attempting to measure those relationships. We then review the implications of this evidence for future mergers, merger policy and the research agenda.
A new confirmation of voltage collapse via instantaneous time domain simulation

This paper aims at capturing the voltage collapse trajectories beyond the steady state loading limit for power systems immediately following a branch outage. Instantaneous Time Domain Simulations are done with two types of transmission line models: Bergeron Model, and Lumped Parameter Model. The constant power load is modeled as a voltage dependent impedance. The results are compared with the continuation power flow which assesses the steady state loadability of the system.
Can We Prevent Aspiration Pneumonia in the Nursing Home

Aspiration pneumonia is a significant cause of morbidity, hospitalization, and mortality in the nursing home population. Patients who aspirate have three times higher mortality than patients who do not aspirate. We discuss the factors known to increase the risk of aspiration and its consequences, and recognize some of the preventive measures for aspiration pneumonia. We suggest approaches to decrease the risk of this very prevalent syndrome.
A fork junction DNA–protein switch that controls promoter melting by the bacterial enhancer‐dependent sigma factor

Results of binding assays using DNA fork junction probes indicate that sigma 54 contains multiple determinants that regulate melting to allow RNA polymerase to remain in closed promoter complexes in order to respond to enhancers. Gel mobility shift studies indicate that the -12 promoter element and parts of sigma 54 act together to form a molecular switch that controls melting. The DNA sequences and the sigma 54 N-terminus help direct polymerase to the location within the -12 promoter element where melting will initiate. However, the fork junction that would lead to melting does not form, due to the action of an inhibitory DNA element. Such unregulated melting is inhibited further by the lack of availability of the single-strand binding elements, which are needed to spread opening from the junction to the transcription start site. Thus, in the absence of looping enhancer protein, proper regulation is maintained as the sigma 54 polymerase remains bound in an inactive state. These complex protein-DNA interactions allow the controls over protein recruitment and DNA melting to be separated, enhancing the diversity of accessible mechanisms of transcription regulation.
Optimal placement of replicas in trees with read, write, and storage costs

We consider the problem of placing copies of objects in a tree network in order to minimize the cost of servicing read and write requests to objects when the tree nodes have limited storage and the number of copies permitted is limited. The set of nodes that have a copy of the object is the residence set of the object. A node wishing to read the object will read the object from the closest node in the residence set. A node wishing to update the object will update the copy of the object at all the nodes in the residence set. Updates are propagated over a certain minimum spanning tree. The cost associated with a residence set equals the cost of servicing all the read and write requests and the storage costs for those copies. We describe an O(n/sup 3/p/sup 2/)-time algorithm for finding an optimal residence set of size p for an object in a tree with n nodes, taking into consideration the read, write, and storage costs. Furthermore, we describe a O(n/sup 3/p/sup 2//spl Lambda//sub max//sup 2/)-time algorithm for finding a minimum cost normal p-residence set for an object in a tree, this time also taking into account the load imposed by the nodes of the tree on the nodes in a residence set and their capacity constraints, where /spl Lambda//sub max/ is an upper bound on the capacity of each node of the tree.
A 20-Year Record of the Western Prairie Fringed Orchid (Platanthera praeclara): Population Dynamics and Modeling of Precipitation Effects

ABSTRACT: Western prairie fringed orchid (Platanthera praeclara) populations may be highly variable over time. It is thought that soil moisture, and potentially disturbance, play important roles in determining abundance and flowering in this species. We present data for a P. praeclara population in southwestern Minnesota that has been monitored annually for 20 years. The number of flowering orchids varied over this period from 0 to 722. We provide an empirical test of an earlier model of precipitation effects during phenological life stages of the orchid, finding that the model was no better than a simple null model that ignored variability in precipitation. We re-examined the relationship between number of flowering orchids and precipitation during phenological life stages based on a modern information theoretic (AIC), multimodel inference approach, and a larger data set. The models indicate the importance of precipitation during three phases of orchid life history: (1) mature growth in the previous year...
Mothers, Faggots, and Witnessing (Un)Contestable Experience:

In this essay, I make two suggestions about personal experience represented in writing. First, I suggest that this experience can be contested when the conditions and the representation of experience are critiqued rather than the experience itself. Second, I suggest that personal experience represented in writing, for example, an autoethnography, can also be “uncontestable” (Scott, 1991, p. 777). An autoethnography is not a disembodied text. A body, a subject, a vulnerable body and subject, is intertwined with and constituted by this text. As such, it becomes difficult to disentangle an autoethnographic representation from its corresponding, constituted-via-this-representation body and subject, thus making a critique of the text a critique of the life.
Notes on the Genus Aporpium (Auriculariales, Basidiomycota), with a New Species from Temperate Europe

A new polypore, Aporpium macroporum Niemela, Spirin & Miettinen, is described on the basis of material from Finland, Poland (Bialowieza National Park; type locality), European Russia, Belarus, Estonia, and Latvia. It grows primarily on fallen aspen trees and prefers old forests with abundant coarse woody debris. Aporpium caryae is an American taxon, and its European kin is A. canescens; A. macroporum differs from them in having wider pores, softer consistency, and paler colours. The spores of the new species are wider than in A. canescens, and longer than in A. caryae. The three species can be distinguished by their ribosomal DNA ITS sequences. We briefly discuss the heterobasidioid genera Aporpium, Elmerina and Protomerulius.
Vertically aligned BaTiO3 nanowire arrays for energy harvesting

Nano-electromechanical systems (NEMS) developed using piezoelectric nanowires (NWs) have gained immense interest in energy harvesting applications as they are able to convert several different forms of mechanical energy sources into electric power and thereby function as reliable power sources for ultra-low power wireless electronics. In this work, a piezoelectric NEMS vibrational energy harvester is fabricated through the development of a synthesis process for vertically aligned barium titanate (BaTiO3) nanowire (NW) arrays directly on a conductive substrate. These poled ferroelectric NW arrays are characterized through direct vibration excitation and demonstrated to provide efficient harvesting of mechanical vibrational energy producing an average power density of ∼6.27 μW cm−3 from 1g acceleration. In order to substantiate the superior energy harvesting performance of the newly developed BaTiO3 NW arrays, a direct comparison is made with conventional ZnO NW arrays. Here, we clearly report that the ferroelectric BaTiO3 NW NEMS energy harvester has ∼16 times greater power density than the ZnO NW NEMS energy harvester from the same acceleration input.
Diverse capacity for 2-methylhopanoid production correlates with a specific ecological niche

Molecular fossils of 2-methylhopanoids are prominent biomarkers in modern and ancient sediments that have been used as proxies for cyanobacteria and their main metabolism, oxygenic photosynthesis. However, substantial culture and genomic-based evidence now indicates that organisms other than cyanobacteria can make 2-methylhopanoids. Because few data directly address which organisms produce 2-methylhopanoids in the environment, we used metagenomic and clone library methods to determine the environmental diversity of hpnP, the gene encoding the C-2 hopanoid methylase. Here we show that hpnP copies from alphaproteobacteria and as yet uncultured organisms are found in diverse modern environments, including some modern habitats representative of those preserved in the rock record. In contrast, cyanobacterial hpnP genes are rarer and tend to be localized to specific habitats. To move beyond understanding the taxonomic distribution of environmental 2-methylhopanoid producers, we asked whether hpnP presence might track with particular variables. We found hpnP to be significantly correlated with organisms, metabolisms and environments known to support plant–microbe interactions (P-valueo10 � 6 ); in addition, we observed diverse hpnP types in closely packed microbial communities from other environments, including stromatolites, hot springs and hypersaline microbial mats. The common features of these niches indicate that 2-methylhopanoids are enriched in sessile microbial communities inhabiting environments low in oxygen and fixed nitrogen with high osmolarity. Our results support the earlier conclusion that 2-methylhopanoids are not reliable biomarkers for cyanobacteria or any other taxonomic group, and raise the new hypothesis that, instead, they are
Marginal costing methods highlight the contributing cost of comorbid conditions in Medicare patients: a quasi-experimental case-control study of ischemic stroke costs.

Background Cost of illness studies are needed to provide estimates for input into cost-effectiveness studies and as information drivers to resource allocation. However, these studies often do not differentiate costs associated with the disease of interest and costs of co-morbidities. The goal of this study was to identify the 1-year cost of ischemic stroke compared to the annual cost of care for a comparable non-stroke group of South Carolina (SC) Medicare beneficiaries resulting in a marginal cost estimate.
Silica-Encapsulated Nanoparticle Films as Surface Modifications for MEMS

In an effort to improve the reliability of microelectromechanical systems (MEMS), silica thin films deposited by chemical vapor deposition were used to encapsulate gold nanoparticle coatings. These composite coatings were shown to provide extremely durable films that significantly reduce the adhesion energy of silicon-based microcantilever beams. The results discussed suggest that encapsulating nanoparticle films with a durable silica thin film may lead to improved MEMS reliability.
Evaluation of patella viability after disruption of the arterial circulation

Fifty patients whose surgical approach violated the arterial geniculate circulation to the patella were evaluated to determine the subsequent effect on patella viability. Comparative postoperative radionuclide scans in 100 knees, 50 control and 50 surgical, revealed an avascular insult in only 7 knees (14%). It appears that the intratendinous circulation described by Bjorkstrom and Goldie protects the patella from an avascular insult in the presence of geniculate arterial disruption.
Crime, punishment, and recidivism - lessons from the National Hockey League.

Among the fundamental elements of the sport of ice hockey are the on-ice rules violations occasionally committed by players and the penalties assessed for those violations. During the 1998-99 season, the National Hockey League (NHL) for the first time experimented with the deployment of two on-ice referees for a selection of games instead of the customary single referee, significant in that only referees have the authority to call penalties. In this article, that experimental 1998-99 season provides the empirical setting for a test of the economic model of crime, which suggests that economic agents allocate time to legal and illegal activity by considering the benefits and costs of these activities. Here, those economic agents are NHL players. Empirically, relatively nonviolent illegal activity appears significantly influenced by benefits and costs, but particularly violent acts appear to occur more randomly. Particularly violent penalties increase when a second referee is deployed, suggesting a dominant ...
Online risk-based security assessment

The work described in this paper was motivated by a perceived increase in the frequency at which power system operators are encountering high stress in bulk transmission systems and the corresponding need to improve security monitoring of these networks. Online risk-based security assessment provides rapid online quantification of a security level associated with an existing or forecasted operating condition. One major advantage of this approach over deterministic online security assessment is that it condenses contingency likelihood and severity into indices that reflect probabilistic risk. Use of these indices in control room decision making leads to increased understanding of potential network problems, including overload, cascading overload, low voltages, and voltage instability, resulting in improved security-related decision making. Test results on large-scale transmission models retrieved from the energy-management system of a U.S. utility company are described.
Synthetic Seed for Clonal Production of Crop Plants1

Seed is the preferred planting vehicle for all crop plants due to ease of production and handling. For many crops (e.g. cereals, soybean etc.), genetically similar seed can be generated by self-pollination whereas, for others, uniform seed cannot be produced due to genetic self-incompatibilities as well as a variety of other reasons. In these latter instances, plants are propagated either vegetatively (e.g. fruit crops) or by genetically nonuniform seed (e.g. forage grasses). Even with self-pollinated crops, plants from different seeds are not genetically identical since they are subject to meiotic recombination during sexual reproduction (exceptions are crops that produce seed apomictically). Thus, elaborate and time consuming breeding systems have been developed in order to exploit hybrid vigor while maintaining seed uniformity.
Modeling a Society of Mobile Heterogeneous Individuals

This chapter describes a model of individuals moving about on a lattice. The system isdecentralizedin that there is no central authority deciding which individuals will remain where they are, which individuals will move, and to where they will move. Instead, on each time step, every individual on the lattice attempts to move at the same time (this is known as synchronous updating) and the movement is local in the sense that an individual can only move from his current lattice site location to an adjacent site and not to a site farther away. We want to avoid having individuals bumping into one another in the process of moving and since there is no traffic controller to coordinate the movements of people, two requirements are imposed on each individual that must be met in order for him to make a move, as opposed to remaining in place: the adjacent site that the individual is attempting to move to must not already be occupied by another individual and the move must not cause a collision with another individual trying to move onto the same site. As we show, we are able to express the rules governing movement subject to these conditions in a set of 28 rules, each having a very simple form. In subsequent chapters (except in the final chapter where nonlocal movement to faraway sites is allowed), these rules are used to incorporate the movement of individuals into other models of socioeconomic behavior since the mobility of individuals is a central feature in many human activities.
Parameters of the Man-Child Bond

Two sets of data have presented themselves to be analyzed. One set suggests a behavioral commonality which in turn suggests a similar factor or cluster of factors causing the commonality. The second set reveals systematic change in how the variables predictably relate to each other.