cssi/SciSciGPT-SciSciNet huggingface dataset:
The Safety of Aggressive Statin Therapy: How Much Can Low-Density Lipoprotein Cholesterol Be Lowered?

Recent clinical trials have consistently demonstrated that reducing low-density lipoprotein cholesterol to very low levels will substantially reduce cardiovascular morbidity and mortality. The lipid-lowering agents of choice are the statins, which are generally considered safe and effective. Of the various agents available, atorvastatin and rosuvastatin are the most powerful, followed by simvastatin. Serious adverse effects with statin therapy are uncommon and primarily involve effects on the liver and skeletal muscle. The risk increases with the statin dose and coadministration with other drugs metabolized by the same metabolic pathway, such as the cytochrome P-450 system. For patients who do not achieve adequate reduction in low-density lipoprotein cholesterol levels with statin therapy of moderate potency, the clinician can up-titrate the dose of the initial statin, institute combination therapy and carefully monitor for adverse effects, or switch to a lower dose of a more potent statin. The strategy chosen depends on the degree of lipid lowering required and on safety, cost, and compliance issues. This article reviews evidence concerning the benefits of reducing low-density lipoprotein cholesterol levels below currently established targets and addresses the question of whether intensive statin therapy is likely to increase the risk of adverse events or concomitant comorbidity.
Transverse dynamics and relaxation in spin-polarized or two-level Fermi systems.

A microscopic theory is proposed for transverse dynamics and zero-temperature attenuation in polarized Fermi liquids. The transport equations are a set of two coupled equations in two ``partial transverse densities,'' which do not reduce to a single equation in a mixed component of a single-particle distribution. The effective interaction is linked to an irreducible vertex by an integral equation, and cannot be given as a limit of a full vertex. A framework for a generalized nonlocal Landau theory is established. The spectrum of attenuating spin waves is calculated at arbitrary polarizations and densities.
Enhanced consumption of salient solutions following pedunculopontine tegmental lesions

Rats with lesions of the pedunculopontine tegmental nucleus (PPTg) reliably overconsume high concentration sucrose solution. This effect is thought to be indicative of response-perseveration or loss of behavioral control in conditions of high excitement. While these theories have anatomical and behavioral support, they have never been explicitly tested. Here, we used a contact lickometer to examine the microstructure of drinking behavior to gain insight into the behavioral changes during overconsumption. Rats received either excitotoxic (ibotenic acid) damage to all PPTg neuronal subpopulations or selective depletion of the cholinergic neuronal sub-population (diphtheria toxin-urotensin II (Dtx-UII) lesions). We offered rats a variety of pleasant, neutral and aversive tastants to assess the generalizability and specificity of the overconsumption effect. Ibotenic-lesioned rats consumed significantly more 20% sucrose than sham controls, and did so through licking significantly more times. However, the behavioral microstructure during overconsumption was unaffected by the lesion and showed no indications of response-perseveration. Furthermore, the overconsumption effect did not generalize to highly consumed saccharin. In contrast, while only consuming small amounts of quinine solution, ibotenic-lesioned rats had significantly more licks and bursts for this tastant. Selective depletion of cholinergic PPTg neurons had no effect on consumption of any tastant. We then assessed whether it is the salience of the solution which determines overconsumption by ibotenic-lesioned rats. While maintained on free-food, ibotenic-lesioned rats had normal consumption of sucrose and hypertonic saline. After mild food deprivation ibotenic PPTg-lesioned rats overconsumed 20% sucrose. Subsequently, after dietary-induced sodium deficiency, lesioned rats consumed significantly more saline than controls. These results establish that it is the salience of the solution which is the determining factor leading to overconsumption following excitotoxic PPTg lesion. They also find no support for response-perseveration contributing to this effect. Results are discussed in terms of altered dopamine (DA) and salience signaling.
Tocainide therapy for treatment of ventricular arrhythmias: assessment with ambulatory electrocardiographic monitoring and treadmill exercise.

Abstract Tocainide has shown promise in the acute suppression of ventricular arrhythmias and in the treatment of such arrhythmias considered refractory to other drugs. However, there is little experience with tocainide therapy using currently acceptable statistical end points in patients not receiving conventional antiarrhythmic drugs concurrently. Accordingly, a double-blind, crossover study design was used to compare the effects of 2 week periods of placebo therapy and small dose (400 mg every 8 hours) tocainide therapy in 10 patients with ventricular arrhythmias who were not receiving quinidlne, procainamide or disopyramide. Ventricular arrhythmias were assessed with 24 hour ambulatory electrocardiographic monitoring and treadmill exercise. Individual patients not responding to small dose tocainide with at least an 80 percent decrease in ventricular premature complexes on ambulatory monitoring were given doses of 600 mg and then 800 mg every 8 hours. Small dose tocainide therapy resulted in a decrease in ventricular premature complexes/hour from 364 ± 98 (standard error) to 127 ± 50 (p
Plastic biliary stent patency in patients with locally advanced pancreatic adenocarcinoma receiving downstaging chemotherapy.

Background Plastic stents in patients with biliary obstruction caused by pancreatic adenocarcinoma are typically exchanged at 3-month intervals. Plastic stents may have reduced durability in patients receiving chemotherapy. Objective To determine the duration of plastic biliary stent patency in patients undergoing chemotherapy for pancreatic adenocarcinoma. Design Retrospective, multicenter cohort study. Setting Three tertiary academic referral centers. Patients A total of 173 patients receiving downstaging chemotherapy for locally advanced or borderline resectable pancreatic adenocarcinoma from 1996 to 2013. Interventions Placement of 10F or larger plastic biliary stents. Main Outcome Measurements Primary outcome was overall duration of stent patency. Secondary outcomes included the incidence of premature stent exchange (because of cholangitis or jaundice) and hospitalization rates. Results A total of 233 plastic stents were placed, and the overall median duration of stent patency was 53 days (interquartile range [IQR] 25–99 days). Eighty-seven stents were removed at the time of surgical resection, and 63 stents were exchanged routinely per protocol. The remaining 83 stent exchanges were performed for worsening liver function test results, jaundice, or cholangitis, representing a 35.6% rate of premature stent exchange. The median stent patency duration in the premature stent exchange group was 49 days (IQR 25–91 days) with a 44.6% hospitalization rate. The overall rate of cholangitis was 15.0% of stent exchanges, occurring a median of 56 days after stent placement (IQR 26–89 days). Limitations Retrospective study. Conclusions Plastic biliary stents placed during chemotherapy/chemoradiation for pancreatic adenocarcinoma have a shorter-than-expected patency duration, and a substantial number of patients will require premature stent exchange. Consideration should be given to shortening the interval for plastic biliary stent exchange.
Understanding the requirements for developing open source software systems

Presents an initial set of findings from an empirical study of social processes, technical system configurations, organisational contexts and interrelationships that give rise to open software. The focus is directed at understanding the requirements for open software development efforts, and how the development of these requirements differs from those traditional to software engineering and requirements engineering. Four open software development communities are described, examined and compared to help discover what these differences may be. Eight kinds of software informalisms are found to play a critical role in the elicitation, analysis, specification, validation and management of requirements for developing open software systems. Subsequently, understanding the roles these software informalisms take in a new formulation of the requirements development process for open source software is the focus of the study. This focus enables the consideration of a reformulation of the requirements engineering process and its associated artefacts, or (in)formalisms, to better account for the requirements for developing open source software systems.
LA ENSEÑANZA DEL ESPAÑOL A HISPANOHABLANTES: PRAXIS Y TEORÍA. M. Cecilia Colombi and Francisco X. Alarcón (Eds.). Boston, MA: Houghton Mifflin, 1997. Pp. xiv + 343. $25.47 paper.

This edited volume consists of 20 chapters, and all but 3 are written in Spanish. The chapters are grouped under four major sections: the classroom, the standard language, teaching language through culture, and political aspects of the maintenance of Spanish. Each section is preceded by an overview.
Interaction of polyamines and magnesium with casein kinase II.

Abstract In reticulocytes, polyamines appear to be physiologically relevant activators of casein kinase II [ Hathaway, G. M. and Traugh, J. A. (1984) . J. Biol. Chem. , 259 , 7011–7015]. The mechanism by which polyamines and Mg 2+ interact to activate casein kinase II has been investigated. These studies were conducted by holding ionic strength constant at 0.10 m . At low Mg 2+ (2.5 m m ), activation by spermine resulted in a 33% decrease in the apparent K m for casein. Under these conditions, a 2.3-fold increase in the maximum velocity of the reaction was observed, and half-maximal stimulation was obtained with 275 μ m spermine. At a kinetically optimal Mg 2+ concentration of 12.5 m m , the effects of spermine on K m and V max were reduced, and the concentration of spermine required to give 50% of maximal stimulation was increased to 750 μ m . Kinetic data obtained at the two Mg 2+ concentrations indicated that Mg 2+ and spermine competed for the same form of the enzyme. Double-reciprocal plots of velocity versus Mg 2+ concentration showed downward curvature at Mg 2+ concentrations higher than 1 m m , and these results were interpreted as evidence for two binding sites on the enzyme with an apparent K m of 0.5 and 2.5 m m . Experiments carried out with ATP-Mg 2+ in the absence of excess MgCl 2 gave results consistent with an absolute requirement of the enzyme for the metal ion which could not be replaced by spermine. These results are consistent with the formation of an enzyme-activator complex. A model is proposed where spermine activates casein kinase II at one site on the enzyme at which MgCl 2 can also bind, while a second, high-affinity site exists exclusively for the metal ion.
Incidental Conversion to Sinus Rhythm from Atrial Fibrillation During External Jugular Venous Catheterization

External jugular venous (EJV) catheterization is a frequent method of gaining central venous access because of its low complication rate. We describe a unique experience during EJV in which a patient with chronic atrial fibrillation converted suddenly to a sustained sinus rhythm without perioperative complication from this event. Our experience depicts a rare consequence of the central catheter placement and we, as anesthesiologists, should be aware of its potential occurrence in the operating room.
The contribution of reactive carbon emissions from vegetation to the carbon balance of terrestrial ecosystems

About 2.4 Pg (1 Pg ¼ 10 15 g) of carbon is emitted annually into the atmosphere as reactive compounds and most of it is eventually oxidized to CO2. Isoprene, a-pinene, methanol, carbon monoxide and other compounds emitted by terrestrial vegetation contribute about half of the total flux and are estimated to produce about 1 Pg C as CO2 per year. The global average for vegetated surfaces is about 7 g C m � 2 per year but could exceed 100 g m � 2 per year at some tropical locations. The magnitude of these fluxes on both the landscape and global scales are small relative to the total carbon emission or deposition but are significant relative to the net fluxes. Reactive carbon fluxes are very sensitive to landcover and climate change and may vary significantly due to future perturbations. This paper summarizes what is known about reactive carbon emissions from vegetation including the magnitude of local, landscape, and global scale fluxes and their contribution to atmospheric CO2. Reasons for including this term in carbon flux models are presented as well as the potential importance on various spatial scales. Past, present and future reactive carbon emissions are expected to differ significantly and the implications of this are discussed. 2002 Elsevier Science Ltd. All rights reserved.
Assay, properties and tissue distribution of p-hydroxyphenylpyruvate hydroxylase.

Abstract Two methods for the assay of p -hydroxyphenylpyruvate hydroxylase ( p -hydroxyphenylpyruvate, ascorbate: O 2 oxidoreductase (hydroxylating), EC 1.14.2.2) activity are described. (1) Chemical method: The homogentisate formed was condensed with cysteine to yield a 1,4-thiazine with an absorption maximum at 390 nm. (2) Radiochemical assay: The release of 14 CO 2 from p -hydroxyphenyl[ carboxy - 14 C]-pyruvate was used as a measure of enzyme activity. Enzyme activation by certain reducing agents, pH optimum, tissue distribution, and fetal and adult enzyme activities are reported. Phenylpyruvate and 3,4-dihydroxyphenylpyruvate were substrates of the enzyme and were mutually competitive to p -hydroxyphenylpyruvate oxidation. The substrates, p -hydroxyphenylpyruvate and oxygen, are inhibitory at high concentration. Hydrogen peroxide, generated by the substrate and oxygen, may account for the observed substrate inhibition. The enzyme is found only in liver and kidney. The significance of these findings to phenylketonuria and tyrosinemia is discussed.
Communication apprehension in a first language and self‐perceived competence as predictors of communication apprehension in a second language: A study of speakers of English as a second language

This study addresses the communication apprehension of the non‐native English speaker in the U.S. Previous studies which have examined the implications of communication apprehension (CA) for bilingual, non‐native communicators have generated results which indicate that trait‐like CA is consistent across first and second language‐speaking situations. However, none of these studies have probed the cause of the cross‐linguistic consistency of CA. This research is designed to provide a scientific explanation for the etiology of CA by applying the communibiological paradigm to CA theory and research. By selecting the situational constraints of international students, this study tests a theory based on proposition 4 of the communibiological paradigm (Beatty & McCroskey w/Valencic, 2001, p. 128): “Environment or ‘situation’ has only a negligible effect on interpersonal behavior.” The results of this study replicate the strong relationship previously observed between CA in a first language and CA in a second lang...
Studying online: evaluation of an online study environment

This study evaluates student use of an online study environment. Its purposes were to (1) determine if college students will voluntarily use online study tools, (2) identify characteristics of users and nonusers of the tools, and (3) determine if the use of online study tools relates to course achievement. Approximately 25 % of students used the online tools for more than one hour before each of three examinations. In comparing use of the study tools provided, the largest number of students made use of the online lecture notes and the greatest amount of online study time was devoted to reviewing multiple choice questions. The perceived ease of access to the Internet differentiated tool users from nonusers. Study tool users scored higher on course examinations after accounting for measures of ability and study skill.
Diffuse scattering from rough surfaces

The problem of diffuse scattering from ocean surfaces defined by a normal stochastic process is under taken. It is assumed that the surface height profile is the sample mean of the number of profiles obtained for the random rough surface. Theoretical expressions for the returned power are developed by using the Helmholtz integral approach with Kirchhoff's approximations for the plane wave case. The plots of scattered power verus surface height roughness parameter are presented.
Fluid-structural interactions using Navier-Stokes flow equations coupled with shell finite element structures

A computational procedure is presented to study fluid-structural interaction problems for three-dimensional aerospace structures. The flow is modeled using the three-dimensional unsteady Euler/Navier-Stokes equations and solved using the finite-difference approach. The three dimensional structure is modeled using shell/plate finite-element formulation. The two disciplines are coupled using a domain decomposition approach. Accurate procedures both in time and space are developed to combine the solutions from the flow equations with those of the structural equations. Time accuracy is maintained using aeroelastic configuration-adaptive moving grids that are computed every time step. The work done by aerodynamic forces due to structural deformations is preserved using consistent loads. The present procedure is validated by computing the aeroelastic response of a wing and comparing with experiment. Results are illustrated for a typical wing-body configuration.
A blue-to-red energy-transfer thymidine analogue that functions in DNA.

The thymidine analogue 1 is a blue-to-red energy transfer cassette designed to absorb UV light in the 300 nm region and emit it as fluorescence at around 520 nm. When incorporated into DNA, the fluorescence intensity of this modified nucleobase is not significantly reduced by the surrounding structure in the oligonucleotides.
Optimal water cost from solar-powered multieffect distillation

Abstract This paper presents a short review of solar distillation followed by a description of conventional distillation methods and associated energy consumption. The paper then presents a system where solar energy is used to generate steam to drive a multieffect distillation plant. The system is optimized on the basis of minimum water cost . The analysis shows that enhancement of heat-transfer coefficients in the distillation section and increasing steam temperature from solar boiler result in lower water cost as well as increase the output per unit area of solar collectors. This study shows that a solar boiler producing saturated steam at 60 C in combination with an evaporator-condenser, developed and tested at this Laboratory, resulted in minimum water costs ranging from $1.40 to $3.70 per m3 for brackish water feed and $2.15 to $4.70 per m3 for seawater feed. At these conditions, the daily productivity per unit area of solar collectors ranged from 45 to 130 liters per m2. This study also shows that when the steam temperature was increased from 60 C to 88 C . the minimum water cost decreased from $2.15/m3 to $1.37/m3 for brackish water feed and from $3.60/m3 to $2.05/m3 for seawater feed. Also, at these conditions, the daily productivity per unit area of solar collector increased to 288 l/m2 for brackish water feed and to 151 l/m2 for seawater feed. These predicted values for the daily productivity are as much as seventy times the average productivity of simple solar stills at the assumed value of solar insolation.
On the difficulty of scalably detecting network attacks

Most network intrusion tools (e.g., Bro) use per-flow state to reassemble TCP connections and fragments in order to detect network attacks (e.g., SYN Flooding or Connection Hijacking) and preliminary reconnaissance (e.g., Port Scans). On the other hand, if network intrusion detection is to be implemented at high speeds at network vantage points, some form of aggregation is necessary. While many security analysts believe that such per-flow state is required for many of these problems, there is no clear proof that this is the case. In fact, a number of problems (such as detecting large traffic footprints or counting identifiers) have scalable solutions. In this paper, we initiate the study of identifying when and how a security attack detection problem can have a scalable solution. We use tools from Communication Complexity to prove that the common formulations of many well-known intrusion detection problems (detecting SYN Flooding, Port Scans, Connection Hijacking, and content matching across fragments) require per-flow state. Our theory exposes assumptions that need to be changed to provide scalable solutions to these problems; we conclude with some systems techniques to circumvent these lower bounds.
A one-dimensional model of mixed cohesive and non-cohesive sediment transport in open channels

A one-dimensional model has been developed to simulate mixed cohesive and non-cohesive sediment transport in open channels. Flocculation is considered by determining the floc settling velocity as function of sediment size, concentration, and bed shear stress. The critical shear stress of cohesive sediment erosion is related to the dry bed density that varies with time due to consolidation, and the critical shear stress of non-cohesive sediments is corrected when the cohesive fraction exceeds a certain limit such as 10%. Cohesive and non-cohesive sediment transport, bed change and bed-material sorting equations are solved in a coupled form. The model is tested using two field cases of mixed sediment transport in the Lower Fox River in USA and the Three Gorges Reservoir in China. The calculated results agree generally well with measured data.
Using a webcast support service: Experiences of in-person attendees of an implantable cardioverter defibrillator support group

Objective Most patients with implantable cardioverter defibrillators (ICDs) adjust well to living with the device; however, some experience difficulties. Support groups assist in coping with the psychologic effects of living with an ICD. The study's aim was to examine acceptability of the in-person attendees of an ICD support group that was cast on the Internet. Sample A patient satisfaction survey describing the participants' experience was used as a measure of acceptability in this non-experimental, survey, pilot study. Methods The survey assessed reactions of the in-person participants with ICDs (N = 46) to the introduction of webcasting and remote participation by other individuals with ICDs. Descriptive statistics were conducted. Results Participating in a webcasted support group was viewed as highly favorable, and responses indicated high satisfaction. Conclusion Participants were satisfied with the webcast technology, enabling broader access to patients. Research is needed to assess the acceptability and satisfaction among remote participants and the group's effectiveness on clinical outcomes.
Understanding Leadership's Moral Dimension

This paper examines morality in the context of a leadership practice defined not in terms of efficiency, but in terms of the unique relationship between leaders and followers. Included is a review ...
Angiotensin II binding sites in the rat fetus: characterization of receptor subtypes and interaction with guanyl nucleotides.

Abstract Angiotensin II (AII) receptor subtypes were studied in the 18-day gestation fetal rat, using two non-peptide AII antagonists: (2- n -butyl-4-chloro-5-hydroxymethyl-1-(2′-(1H-tetrazol-5-yl)biphenyl-4-yl)methyl)imidazol) (DuP 753; type 1 (AT 1 ) specific), and 1-(4-amino-3-methylpenyl)methyl-5-diphenacetyl-4,5,6,7-tetrahydro-1-H-imidazo[4,5-c]pyridine-6-carboxylic acid (PD 123 177; type 2 (AT 2 ) specific). Autoradiography using 125 I-[Sar 1 ,Ile 8 ]AII showed that 10 μM PD 123 177 decreased binding to near-nonspecific levels in skin, skeletal muscle and adrenal medulla, whereas 10 μM DuP 753 blocked binding in the liver and lung. Studies in skin and liver membranes confirmed the autoradiographic data: AT 1 receptors were predominant in the liver (95%), and AT 2 in the skin (97%). There was no cross-reactivity between receptor subtype and the heterologous antagonist up to a concentration of 10 μM. In both skin and liver, 2 mM dithiothreitol enhanced the binding of AT 2 receptors by increasing receptor affinity, but inhibited binding of AT 1 by decreasing the receptor number. In the absence of antagonists, guanyl nucleotides, added at equilibrium, caused marked dissociation of 125 I-AII binding in liver membranes, but had minimal effect in skin. However, dissociation occurred in the skin when AT 2 sites were blocked with 10 μM PD 123 177, and in liver, dissociation was not observed when AT 1 sites were blocked with DuP 753. Hence, in contrast to classical AII target tissues, which contain predominantly AT 1 , most of the sites in fetal skin and skeletal muscle are AT 2 . The demonstration that the effects of guanyl nucleotides are selective for receptor subtype suggests that the AT 1 receptor, but not the AT 2 , is coupled to cell function via guanyl nucleotide binding proteins. The functional importance of the AT 2 receptors and their role in fetal physiology is under current investigation.
ANALYSIS AND MEASUREMENT OF SOUND TRANSMISSION THROUGH A DOUBLE-WALLED CYLINDRICAL SHELL

Sound transmission through a double-walled cylindrical shell is studied. The solution that describes the system response is obtained by combining the solutions of two different models of the system. The first model, which describes the sound transmission due to the interaction between the acoustic waves and the bending waves in the shells, is formulated by three acoustic wave equations and two shell vibration equations. The second model describes the sound transmission by one-dimensional waves propagating through the layers of the shells and the air-gap. The transmission losses calculated from the two models are combined to represent the system response in the entire frequency range. Analytical solutions are compared to corresponding measured results, which shows reasonable agreements if the extent of the simplifications used in the analytical model is considered. The effects of important design parameters such as the air-gap size and the thickness ratio are studied using analytical solutions.
Cauchy-Difference Conservative Vector Fields for Dimension Two and Three

Let G be an abelian group and X a vector space over the rationals. If Φ: G → X its 1st Cauchy difference is the function K2Φ:G2 → X defined by K2Φ(x 1, x2) = Φ(x1 + x2) − Φ(x1) − Φ(x2) and in general for n = 2, 3, … the (n − 1)th Cauchy difference of Φ is the function, K nΦ: Gn → X, defined by % MathType!MTEF!2!1!+-% feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXanrfitLxBI9gBaerbd9wDYLwzYbItLDharqqt% ubsr4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq% -Jc9vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0x% fr-xfr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyuam% aaBaaaleaacaaIXaGaaGimaaqabaGccqGH9aqpciGGSbGaaiOBaiaa% ysW7caWGRbWaaSbaaSqaaiaadsfacaaIXaaabeaakiaac+cacaWGRb% WaaSbaaSqaaiaadsfacaaIYaaabeaakiabg2da9iabgkHiTmaabmaa% baGaamyramaaBaaaleaacaWGHbaabeaakiaac+cacaWGsbaacaGLOa% GaayzkaaGaey41aq7aaiWaaeaadaqadaqaaiaadsfadaWgaaWcbaGa% aGOmaaqabaGccqGHsislcaWGubWaaSbaaSqaaiaaigdaaeqaaaGcca% GLOaGaayzkaaGaai4laiaacIcacaWGubWaaSbaaSqaaiaaikdaaeqa% aOGaaGjbVlaadsfadaWgaaWcbaGaamysaaqabaGccaGGPaaacaGL7b% GaayzFaaaaaa!5C4A! $$K_{n}\Phi(x_{1},\cdot\cdot\cdot,\ x_{n})={\mathop \sum^n\limits_{r=1}}(-1)^{n-r}{\sum \limits_{\mid J\mid=r}}\Phi(x_{j})$$ where ϕ ≠ ⊆ I n = {1, 2, …, n} and x J = Σj∈JxJ. If Ψ: Gn → X(n = 2, 3, …) then its i-th partial Cauchy difference of order r(r = 2, 3, …), Kr (i)Ψ: Gn+r+1 → X, is its Cauchy difference of order r − 1 with respect to its i-th variable with all the other variables held fixed. For n = 2 we have K2 (1)Ψ(x1, x2, x3) = Ψ(x1 + x2, x3) − Ψ(x1, x3) − Ψ(x 2, x3) and K2 (2)Ψ(x1; x2, x3) = Ψ(x1, x2 + x3) − Ψ(x1, x2) − Ψ(x1, x3). In this paper if ƒ = : G n → xn the solution of K2 (i) ƒ j = K2 (j) ƒ i (i ≠ j) is given for n = 2 and 3.
Reactive Transport in Porous Media: A Comparison of Model Prediction with Laboratory Visualization

Groundwater transport models that accurately describe spreading of nonreactive solutes in an aquifer can poorly predict concentrations of reactive solutes. The dispersive term in the advection-dispersion equation can overpredict pore-scale mixing, and thereby overpredict homogeneous chemical reaction. We quantified this experimentally by imaging instantaneous colorimetric reactions between solutions of aqueous CuSO4 and EDTA4- within a 30-cm long translucent chamber packed with cryolite sand that closely matched the optical index of refraction of water. A charge-coupled device camera was used to quantify concentrations of blue CuEDTA2- within the chamber as it was produced by mixing of the two reactants at different flow rates. We compared these experimental results with a new analytic solution for instantaneous bimolecular reaction coupled with advection and dispersion of the product and reactants. For all flow rates, the concentrations of CuEDTA2- recorded in the experiments were about 20% less than predicted by the analytic solution, thereby demonstrating that models assuming complete mixing at the pore scale can overpredict reaction during transport.
Making Sense of Methods and Measurement: Reliability

Reliability in simulation research depends on the investigator’s ability to provide both a consistent experience and evaluation of student learning and performance. This column will focus on the concept of reliability as it relates to simulation research. Reliability is a measure of consistency or stability. In other words, if a participant’s performance is measured several times using the same instrument, then a similar score is achieved each time, given that nothing else has changed. If a student is evaluated in a simulated environment at the beginning and end of the semester, we would expect that the student’s overall performance would improve because the student has gained a semester’s worth of content knowledge and skills. A difference in scores from the beginning to the end of the semester doesn’t mean that the data from the instrument are unreliable but instead reflects the actual change in performance by that participant. If similar students at the same level (for example, beginning 2nd-year students) are all evaluated at the same time with the same instrument, and the scores are wildly different, we would suspect that the data from the instrument may be unreliable. Unreliable data from an instrument are not logical, generalizable, or transferrable. In other words, these data are unusable. In assessing reliability, one needs to examine both the test, or the simulation experience that allows the student to demonstrate his or her knowledge, skills, and behaviors, and the evaluation strategies that allow an observer to quantify and interpret the student’s demonstration of knowledge, skills, and behaviors (American Educational
Industry survey of wafer fab reticle quality control strategies in the 90nm-45nm design-rule age

Reticle quality control in wafer fabs is different from quality control in mask shops. Mask shop requirements are typically inspectability of mask-type, resolution and sensitivity, with the latter usually being the most important. Mask shop sensitivity requirements are also fairly absolute. All defects or imperfections of a certain specification have to be found 100 percent of the time, every time. Wafer fab requirements are an interplay between inspectability, sensitivity, and the economic cost of inspection versus the economic risk of not inspecting. Early warning and defect signatures versus absolute capture of all defects is a key distinction between wafer fabs and mask shops. In order to better understand the different strategies and approaches taken by wafer fabs for reticle quality control an industry-wide benchmark survey of leading wafer fabs was undertaken. This paper summarizes the results while retaining the different wafer fabs' anonymity and confidentiality. The approach taken for the survey was specifically designed to be impartial and independent of any tools, solutions or applications available from KLA-Tencor.
Triangle surfaces with discrete equivalence classes

We propose a technique that takes a triangulated surface as input and outputs a surface with the same topology but altered geometry such that each polygon falls into a set of discrete equivalence classes. We begin by describing an error function that measures how close the polygons are to satisfying this criteria. To optimize this error function, we first cluster triangles into discrete sets such that the assignment of sets minimizes our error. We then find canonical polygons for each set using nonlinear optimization. Next, we solve a Poisson equation to find positions of vertices such that the surface polygons match the canonical polygons as close as possible. We also describe how to incorporate a fairness criteria into the optimization to avoid oscillations of the surface. We iterate this entire process until we reach a user specified tolerance, possibly adding clusters during iteration to guarantee convergence. We have been able to successfully reduce the number of unique triangles to lie within a small percentage of the total number of triangles in the surface and demonstrate our technique on various examples.
The procyanidins of Douglas fir seedlings, callus and cell suspension cultures derived from cotyledons

Abstract While cotyledons of Douglas fir seedlings contain only 2–3% of their dry weight as procyanidins (mainly in an insoluble form), callus cultures and cell suspension cultures derived from them contain up to 40%. About 70–85% of the procyanidins isolated from these cell suspension cultures are soluble in 70% methanol, but insoluble in ethyl acetate. They can be separated into a minimum of 4 fractions, all of which have apparent molecular weights greater than that of a tetramer. Dimers, trimers or tetramers are absent or present in only trace amounts, but large amounts of catechin, and lesser amounts of epicatechin, are found in the ethyl acetate-soluble fraction.
Biologic Limits of Viability: Implications for Clinical Decision-making

After completing this article, readers should be able to: 1. Define the gestational range for extremely preterm birth. 2. Explain the difference between possibility and probability in reference to survival following extremely preterm birth. 3. Describe the key lung development required for adequacy of gas exchange. 4. Describe the renal functional limitations for water, sodium, and creatinine homeostasis in the first postnatal week of the extremely preterm infant. 5. List at least one structural and/or functional limitation of at least five organ systems that increases mortality risks for the extremely preterm infant. With the advent of neonatal intensive care in the 1960s, preterm infants born at progressively lower gestational ages began to survive. The progression of the decrement did not follow a recognizable relationship; rather, it was erratic as the knowledge base of neonatal physiology and pathology expanded and new technical capabilities for life support were developed. The most dramatic increase in survival of extremely preterm birth (<26 completed weeks’ gestation) came with the introduction of surfactant replacement therapy in the late 1980s. The increased use of maternal antenatal corticosteroid therapy for induction of lung maturation with threatened preterm delivery following the National Institute of Child Health and Human Development Consensus Conference recommendations in 1994 also contributed to improved survival. Since that time, the survival of infants of gestational ages as low as 22 weeks’ has been reported. The purpose of this article is to review the current understanding of the biologic factors limiting survival potential, particularly as they inform clinical decision-making. Viability or survival potential, when used in reference to a fetus, frequently is used to indicate the possibility for a fetus to be live born and capable of living to a specified endpoint of either a designated time, reaching a certain age or a landmark event, admission to a neonatal intensive care unit, …
Discussion of Corporate Governance Reform and Executive Incentives: Implications for Investments and Risk Taking

We discuss the strengths and weaknesses of the article by Cohen, Dey and Lys (CDL). Strengths include persuasive theoretical arguments for impacts of the Sarbanes Oxley Act (SOX) on corporate investment strategies and for several mechanisms through which firms influence changes in risky investments. CDL also provides intriguing opportunities for learning about impacts of external regulatory events and for enriching management accounting research and classroom discussions of management control. Weaknesses include (1) narrow scope, perhaps driven by archival data availability; (2) difficulties in implementing the research design and method; (3) possible bias of incentive and investment measures; (4) incomplete estimates of the effect of SOX on compensation, incentives, and investments; and (5) questionable control of endogeneity. We offer recommendations from extant literature to mitigate these weaknesses in future research.
Frequency analysis of CD4+CD8+ T cells cloned with IL-4

The coexpression of both CD4 and CD8 molecules on T cells occurs in the peripheral blood at a low frequency and can be generated transiently on CD4+ peripheral blood T cells by treatment with lectin which induces CD8 biosynthesis and cell surface expression. We have cloned T cells in a nonselective fashion from normal subjects in the presence of either IL-2, rIL-4 and IL-2, or rIL-4 and have examined the phenotypic expression of CD4 and CD8. The addition of excess rIL-4 increased the expression of CD8 on the surface of CD4+ T cell clones but did not increase CD4 expression on CD8+ T cell clones. There were three patterns of CD4 and CD8 expression observed: high density CD8 with no CD4 expression; high density CD4 with low CD8 expression; or high density CD4 with higher cell surface CD8 expression which was regulated by the presence of rIL-4. CD4+ T cell clones originally cultured in IL-2 and rIL-4 and subsequently grown in IL-2 alone exhibited decreased expression of the CD8 molecule. The increased expression of CD8 did not correlate with NK activity or lectin-dependent cytotoxicity in an antigen independent system. In addition, rIL-4 alone or in combination with IL-2 appeared to accelerate the growth curve of T cell clones as compared to IL-2 alone. These results show that IL-4 can upregulate CD8 expression on CD4+ T cell clones while not effecting CD4 expression on CD8+ T cell clones. As class I MHC is the ligand for the CD8 molecule, expression of CD8 induced by IL-4 on CD4+ T cells may allow for increased nonspecific cell to cell contact during the course of an inflammatory response.
Simultaneous Confidence Intervals for Functions of Variance Components in Random Models

Abstract Interval estimation of certain functions of variance components is of interest to research workers in all fields of applications in which the variance component model is used. Confidence intervals for linear functions and ratios of variance components have been proposed by several authors. For the most part, these intervals are approximate with unknown exact probabilities associated with their coverage. In this article a technique is given for the construction of simultaneous confidence intervals for the values of all continuous functions of the variance components in a balanced, general random linear model. These confidence intervals are conservative; that is, the actual confidence level cannot be less than any preset value. The proposed technique is easy to apply as it only requires the optimization of a given continuous function of the variance components over a bounded region. Several examples of continuous functions are considered, including linear functions and ratios of variance components...
A universal relationship for estimating clear sky insolation

An investigation of estimating clear sky insolation1 has been conducted. Some discrepancies have been found between the conventional method of estimation and the data. It has been noticed that the conventional method underestimates the insolation. A simpler, more elegant and more accurate “universal” relationship has been derived for estimating the annual mean daily clear sky insolation as a function of the latitude and altitude of a given location. As part of this derivation, two simple and accurate correlations have been obtained, i.e. for extraterrestrial insolation and for atmospheric attenuation.
Notch-1 Inhibition by Withaferin-A: A Therapeutic Target against Colon Carcinogenesis

Notch signaling plays a crucial role in the development of colon cancer; targeting the Notch pathway may sensitize colon cancers to various adjuvant agents. The focus of our current study is to identify natural compounds that target Notch signaling and that might be beneficial for the prevention and treatment of colon cancer. Withaferin-A (WA) is a bioactive compound derived from Withania somnifera, which inhibits Notch-1 signaling and downregulates prosurvival pathways, such as Akt/NF-kappaB/Bcl-2, in three colon cancer cell lines (HCT-116, SW-480, and SW-620). In addition, WA downregulated the expression of mammalian target of rapamycin signaling components, pS6K and p4E-BP1, and activated c-Jun-NH(2)-kinase-mediated apoptosis in colon cancer cells. We also established the molecular link between Notch/Akt/mammalian target of rapamycin signaling by complementary approaches (i.e., overexpression of Notch-1 or inhibition of Notch-1 by small interfering RNA). Our results suggest that WA inhibits Notch-mediated prosurvival signaling, which facilitates c-Jun-NH(2)-kinase-mediated apoptosis in colon cancer cell lines. These results underscore the anticancer activity of WA, which exhibits potential for further development for targeted chemotherapy and/or chemoprevention strategies in the context of colon cancer.
What is suppressed during binocular rivalry

To answer the question 'what is suppressed during binocular rivalry?" a series of three experiments was performed. In the first experiment observers viewed binocular rivalry between orthogonally oriented patterns. When the dominant and suppressed patterns were interchanged between the eyes observers continued seeing with the dominant eye, indicating that an eye, not a pattern, is suppressed during rivalry. In a second experiment it was found that a suppressed eye was able to contribute to stereopsis. A third experiment demonstrated that the predominance of an eye could be influenced by prior adaptation of the other eye, indicating that binocular mechanisms participate in the rivalry process.
Error performance analysis of signal superposition coded cooperative diversity

This paper analyzes the error performance of a coded cooperative diversity system employing the Euclidean superposition of two BPSK-modulated signals. For an example using a convolutional code on block fading channels, the results show excellent agreement with computer simulations. The analysis makes it possible to optimize the power allocation between the local and relay signals numerically, circumventing the need for time consuming Monte Carlo simulations. Similarly, the analysis demonstrates how the power allocation can be "tuned" to compensate for unbalanced uplink channels and/or to provide unequal error protection to the data from the two cooperating nodes.
Cytokines induce NF-κB in activated but not in quiescent rat hepatic stellate cells

The hepatic stellate cell (HSC), after a fibrogenic stimulus, is transformed from a quiescent to an activated phenotype, including the induction of responsiveness to a variety of agonists. We investigated the activation of nuclear factor-kappaB (NF-kappaB) and the expression of the NF-kappaB-responsive genes intercellular adhesion molecule 1 (ICAM-1) and macrophage inflammatory protein-2 (MIP-2) in freshly isolated and culture-activated HSC by tumor necrosis factor-alpha (TNF-alpha) or interleukin-1beta. Inhibitor-kappaB was rapidly (<15 min) degraded, and NF-kappaB activity was induced in culture-activated but not in freshly isolated HSC after cytokine stimulation. After 30 min of stimulation, immunofluorescence revealed that the NF-kappaB p65 subunit was predominantly found in the nuclei of activated HSC compared with the cytoplasmic localization in unstimulated cells. No nuclear translocation appeared in freshly isolated HSC after stimulation, despite the presence of functional TNF-alpha receptors. NF-kappaB nuclear translocation appeared first partially after 4-5 days and completely after 9 days in culture. Consistent with this time course TNF-alpha induced the mRNA of the NF-kappaB-dependent genes ICAM-1 and MIP-2 in activated but not in quiescent HSC. Therefore, cytokines induce NF-kappaB activity and ICAM-1 and MIP-2 mRNAs in activated but not in quiescent HSC, through a postreceptor mechanism of regulation.
Structural Effects and Translocation of Doxorubicin in a DPPC/Chol Bilayer: The Role of Cholesterol

We use molecular dynamics simulations to characterize the influence of cholesterol (Chol) on the interaction between the anticancer drug doxorubicin (DOX) and a dipalmitoyl phosphatidylcholine/Chol lipid bilayer. We calculate the potential of mean force, which gives us an estimate of the free energy barrier for DOX translocation across the membrane. We find free energy barriers of 23.1 ± 3.1 kBT, 36.8 ± 5.1 kBT, and 54.5 ± 4.7 kBT for systems composed of 0%, 15%, and 30% Chol, respectively. Our predictions agree with Arrhenius activation energies from experiments using phospholipid membranes, including 20 kBT for 0% Chol and 37.2 kBT for 20% Chol. The location of the free energy barrier for translocation across the bilayer is dependent on composition. As Chol concentration increases, this barrier changes from the release of DOX into the water to flip-flop over the membrane center. The drug greatly affects local membrane structure by attracting dipalmitoyl phosphatidylcholine headgroups, curving the membrane, and allowing water penetration. Despite its hydrophobicity, DOX facilitates water transport via its polar groups.
Current Concepts About Chromium Supplementation in Type 2 Diabetes and Insulin Resistance

Chromium has been established to be an essential trace element in mammals in regard to maintenance of normal carbohydrate metabolism. Studies that provided chromium to human subjects in documented deficiency states noted improved glucose levels. However, controversy exists as to whether dietary supplementation with chromium should be routinely recommended in subjects without documented deficiencies. Over the recent past, several well-designed clinical trials have provided evidence in favor of and against a beneficial effect of chromium. It appears that across all subject phenotypes (eg, lean and obese, insulin sensitive and insulin resistant), a consistent significant and beneficial effect of chromium may not be observed. Specifically, recent data fail to demonstrate significant improvement in carbohydrate metabolism in individuals with metabolic syndrome, impaired glucose tolerance, or consistently in individuals with type 2 diabetes. However, patient selection may be an important factor in determining clinical response, as it was concluded that a clinical response to chromium (ie, decreased glucose and improved insulin sensitivity) may be more likely in insulin-resistant individuals with type 2 diabetes who have more elevated fasting glucose and hemoglobin A1c levels.