cssi/SciSciGPT-SciSciNet huggingface dataset:
Detrimental genes with partial selfing and effects on a neutral locus.

Gene and genotypic frequencies for a deleterious mutant in mutation selection balance are derived for an infinite population undergoing partial self-fertilization. These provide formulations of mean survival and the mutational load. Obtained also are the average number of mutant genes and affected individuals stemming from a single mutant.As a concomitant effect on frequencies at a neutral locus the mutational load is distributed disproportionately among the neutral genotypes. For partially recessive mutant genes on the 1, 1-sh, 1-s scale, the effect is to increase the frequency of the heterozygote and to decrease the frequencies of homozygotes at the neutral locus relative to the frequencies expected with complete neutrality. This apparent overdominance at the neutral locus has been shown to be connected with identity disequilibrium rather than linkage disequilibrium. It increases generally as s and h decrease, and as the proportion of self-fertilization and the degree of linkage increase. The apparent overdominance with complete linkage is generally less than double that for free recombination. For partially dominant mutant genes, h ≥ ½, the effects on the frequencies of heterozygote and homozygotes at the neutral locus are reversed.
Postprandial energy expenditure in whole-food and processed-food meals: implications for daily energy expenditure

Background: Empirical evidence has shown that rising obesity rates closely parallel the increased consumption of processed foods (PF) consumption in USA. Differences in postprandial thermogenic responses to a whole-food (WF) meal vs. a PF meal may be a key factor in explaining obesity trends, but currently there is limited research exploring this potential link. Objective: The goal was to determine if a particular PF meal has a greater thermodynamic efficiency than a comparable WF meal, thereby conferring a greater net-energy intake. Design: Subjective satiation scores and postprandial energy expenditure were measured for 5-6 h after isoenergetic meals were ingested. The meals were either ‘whole’ or ‘processed’ cheese sandwiches; multi-grain bread and cheddar cheese were deemed whole, while white bread and processed cheese product were considered processed. Meals were comparable in terms of protein (15-20%), carbohydrate (40-50%), and fat (33-39%) composition. Subjects were healthy women (n=12) and men (n=5) studied in a crossover design. Results: There were no significant differences in satiety ratings after the two meals. Average energy expenditure for the WF meal (13± 14.1 kcal, 19.9% of meal energy) was significantly larger than for the PF meal (73± 10.2 kcal, 10.7% of meal energy). Conclusion: Ingestion of the particular PF meal tested in this study decreases postprandial energy expenditure by nearly 50% compared with the isoenergetic WF meal. This reduction in daily energy expenditure has potential implications for diets comprised heavily of PFs and their associations with obesity. Keywords: diet; nutrition; DIT; food processing; energy; metabolism; obesity (Published: 2 July 2010) Citation: Food & Nutrition Research 2010, 54 : 5144 - DOI: 10.3402/fnr.v54i0.5144
Applications of radiation measurements in arms control and nonproliferation

Abstract Radiation measurements play a vital role in the development and implementation of U.S. arms control and nonproliferation policy. The President's Nonproliferation and Export Control Policy reflects the changing realities of a post-Cold-War world and makes nonproliferation one of our nation's highest priorities. Key elements of the Policy concern international controls on plutonium and highly-enriched uranium. Current DOE work contributing to arms control and nonproliferation policy implementation is described with an emphasis on the role of radiation measurements.
Analyzing effect of generation size in intra-session network coding for multiple flows of TCP traffic

With the advancement in network coding, the congestion avoidance problems in TCP are now being explored from the perspective of a network coding paradigm. Some of the challenges in incorporating network coding along with TCP are the complexity involved in implementation, added redundancy in the network, and added latency due to packet processing. Several methods have been proposed to intelligently combine packets of opposite flows, and/or use two different types of network coding to improve the throughput of the network. However, very few papers have focussed on the effect of redundancy introduced due to network coding and the corresponding effect of the number of packets combined, also known as generation size. Also, none of the previous papers have presented an optimizing model demonstrating the effect of inherent redundancy introduced by network coding for multiple flows in TCP. This paper proposes a simple mathematical framework for optimizing the sending rate for TCP with network coding and the generation size at the sources for multiple flows. The analysis enforces the idea that an adaptive generation size sensitive to losses prevents undesirable packet drops in the network.
From Bacon to Banks: the vision and the realities of pursuing science for the common good.

Abstract Francis Bacon’s call for philosophers to investigate nature and “join in consultation for the common good” is one example of a powerful vision that helped to shape modern science. His ideal clearly linked the experimental method with the production of beneficial effects that could be used both as “pledges of truth” and for “the comforts of life.” When Bacon’s program was implemented in the following generation, however, the tensions inherent in his vision became all too real. The history of the Royal Society of London, from its founding in 1660 to the 42-year presidency of Joseph Banks (1778–1820), shows how these tensions led to changes in the way in which both the experimental method and the ideal of the common good were understood. A more nuanced understanding of the problems involved in recent philosophical analyses of science in the public interest can be achieved by appreciating the complexity revealed from this historical perspective.
Sterile syringe access conditions and variations in HIV risk among drug injectors in three cities.

Aim Better sterile syringe access should be associated with a lower likelihood of syringe re-use and receptive syringe sharing, although few empirical studies have examined gradients in syringe access using both individual and ecological data. In this study, we compare syringe re-use and receptive syringe sharing among injection drug users (IDUs) with syringe exchange program (SEP) and legal over-the-counter pharmacy access with limits on syringes that can be purchased, exchanged or possessed to IDUs with no pharmacy sales but unlimited syringe access through SEPs. We address three questions: (1) Does residing in an area with no legal syringe possession increase the likelihood of police contact related to possessing drug paraphernalia? (2) Among direct SEP users, is use of more permissive SEPs associated with less likelihood of syringe re-use and receptive syringe sharing? (3) Among non-SEP users, is residing in an area with pharmacy access associated with lower likelihood of syringe re-use and receptive syringe sharing? Design Quantitative survey of IDUs recruited from SEPs, subject nomination and outreach methods. Multivariate analyses compared police contact, syringe re-use and receptive syringe sharing among IDUs recruited in three cities. Findings In multivariate analyses, we found that police contact was associated independently with residing in the area with no legal possession of syringes; among SEP users, those with access to SEPs without limits had lower syringe re-use but not lower syringe sharing; and that among non-SEP users, no significant differences in injection risk were observed among IDUs with and without pharmacy access to syringes. Conclusion We found that greater legal access to syringes, if accompanied by limits on the number of syringes that can be exchanged, purchased and possessed, may not have the intended impacts on injection-related infectious disease risk among IDUs.
The Value of the Self in Relation to Fear of Death

A theoretical position on death anxiety advanced by previous authors was tested in this study. Diggory and Rothman reasoned that we try to extend objects that are valued highly, while those of low ...
An optimal O(n) algorithm for identifying line segments from a sequence of chain codes

Abstract An optimal algorithm for identifying straight lines in chain codes is described. The algorithm turns the complicated problem of determining the straightness of digital arcs into a simple task by constructing a passing area around the pixels. It also solves the problem of detecting all straight segments from a sequence of chain codes in O(n) time, where n is the length of the sequence. It has been found that this algorithm is not only simple and intuitive, but also highly efficient.
Unraveling the Reactive Species of a Functional Non-Heme Iron Monooxygenase Model Using Stopped-Flow UV−Vis Spectroscopy

Low-temperature stopped-flow electronic spectroscopy was utilized to resolve the intermediates formed in the reaction of a diiron(II) compound, Fe2(H2Hbamb)2(N-MeIm)2 (H4HBamb = 2,3-bis(2-hydroxybenzamido)dimethylbutane), 1, with the oxygen atom donors 2,6-dimethyliodosylbenzene and p-cyanodimethylaniline N-oxide and the mechanistic probe hydroperoxide 2-methyl-1-phenylprop-2-yl hydroperoxide (MPPH). Previous studies showed that 1 is capable of catalytically oxidizing cyclohexane to cyclohexanol (300 turnovers) via a pathway involving the heterolytic cleavage of the O−O bond of MPPH (>98% peroxide utilization). We now report intimate details of the formation of the reactive intermediate and its subsequent decay in the absence of substrates. The reaction, which is independent of the nature of the oxidant, proceeds in three consecutive steps assigned as (i) oxygen-atom transfer to one of the iron centers of 1 to form an FeIVO species, 2, (ii) ligand rearrangement to 3, and (iii) internal collapse of the ter...
The statistical analysis of insect phenology.

ABSTRACT We introduce two simple methods for the statistical comparison of the temporal pattern of life-cycle events between two populations. The methods are based on a translation of stage-frequency data into individual ‘times in stage’. For example, if the stage-k individuals in a set of samples consist of three individuals counted at time t1 and two counted at time t2, the observed times in stage k would be (t1, t1; t1; t2, t2). Times in stage then can be compared between two populations by performing stage-specific t-tests or by testing for equality of regression lines of time versus stage between the two populations. Simulations show that our methods perform at close to the nominal level, have good power against a range of alternatives, and have much better operating characteristics than a widely-used phenology model from the literature.
HOUSING CROWDING EFFECTS ON CHILDREN'S WELLBEING

The degree to which children grow up in crowded housing is a neglected but potentially important aspect of social inequality. Poor living conditions can serve as a mechanism of social stratification, affecting children's wellbeing and resulting in the intergenerational transmission of social inequality. This paper reports an investigation of housing crowding on children's academic achievement, behavior, and health in the US and Los Angeles, a city with atypically high levels of crowding. We use data from the Panel Study of Income Dynamics' Child Development Supplement and the Los Angeles Family and Neighborhood Survey to explore the effect of living in a crowded home on an array of child wellbeing indicators. We find that several dimensions of children's wellbeing suffer when exposed to crowded living conditions, particularly in Los Angeles, even after controlling for socioeconomic status. The negative effects on children raised in crowded homes can persist throughout life, affecting their future socioeconomic status and adult wellbeing.
Heat measurements applied to biochemical analysis: Glucose in human serum

Abstract Microcalorimetric measurement of enthalpy change for the hexokinase catalyzed reaction of ATP with glucose (inTRIS/HCl buffer containing MgCl 2 ) was carried out with glucose concentrations from zero to 1350 mg · liter −1 . A linear relationship between measured heat and glucose concentration was found, from which the reaction enthalpy was calculated to be −61.4 kJ·mole −1 . This linear relation, combined with calorimetric measurements of the same process carried out with 0.15 ml samples of human serum, was used to calculate glucose concentrations in the serum. For 45 samples containing glucose levels ranging from 420 to about 4000 mg · liter −1 the results show only slight systematic differents from measurements made by the glucose oxidase procedure of Gochman and Schmitz.
The effect of treating air samples with magnesium perchlorate for water removal during analysis for non‐methane hydrocarbons

A comparison has been made between two cryogenic preconcentration - high resolution gas chromatography techniques for the analysis of non-methane hydrocarbons in ambient air, one involving treatment of air samples with magnesium perchlorate to remove water, the other involving analysis without treatment. Recoveries of C1-, C2-, and C3-substituted benzenes in treated samples were 80%, 50%, and 50%, respectively. Incomplete recovery of C7-C9n-1-olefins was also observed. C2-C8 hydrocarbons and C2-C6n-1-olefins were recovered with greater than 90% efficiency. Analyses of certified audit samples containing a mixture of C2-C8 aliphatic and aromatic hydrocarbons at the 20 ppbv level in humidified zero-grade air indicated that the accuracy of the technique for untreated air samples was approximately 90%. The use of magnesium perchlorate for water removal cannot be recommended for the analysis of non-methane hydrocarbons in ambient air.
The significance of Aleš Hrdlička's “Neanderthal phase of man”: A historical and current assessment

Ales Hrdlicka's hypothesis on a Neandertal phase of human evolution is examined in light of current data and interpretations on Neandertals. Hrdlicka's interpretations are related to his ideas regarding the peopling of the New World. A major early statement of Hrdlicka's views on Neandertal was his Huxley Memorial Lecture of 1927. We assess this formulation and subsequent development of his hypothesis. Hrdlicka's position is compared with the “presapiens” and “pre-neandertal” hypotheses on the basis of current theory and data.
Calcite crystal growth rate inhibition by polycarboxylic acids

Abstract Calcite crystal growth rates measured in the presence of several polycarboxyclic acids show that tetrahydrofurantetracarboxylic acid (THFTCA) and cyclopentanetetracarboxylic acid (CPTCA) are effective growth rate inhibitors at low solution concentrations (0.01 to 1 mg/L). In contrast, linear polycarbocylic acids (citric acid and tricarballylic acid) had no inhibiting effect on calcite growth rates at concentrations up to 10 mg/L. Calcite crystal growth rate inhibition by cyclic polycarboxyclic acids appears to involve blockage of crystal growth sites on the mineral surface by several carboxylate groups. Growth morphology varied for growth in the absence and in the presence of both THFTCA and CPTCA. More effective growth rate reduction by CPTCA relative to THFTCA suggests that inhibitor carboxylate stereochemical orientation controls calcite surface interaction with carboxylate inhibitors.
Release of Chlorambucil from Poly(N‐isopropylacrylamide) Hydrogels with β‐Cyclodextrin Moieties

The present work is focused on investigating the behavior of controlled drug release poly(N-isopropylacrylamide) (PNIPA) hydrogels in the presence of beta-cyclodextrin (beta-CD). For this purpose, three types of NIPA hydrogels with beta-CD moieties were synthesized with different architectures according to our previous studies. An anti-cancer drug (chlorambucil, CLB), which can form an inclusion complex with beta-CD, was selected for loading and in vitro release studies. The drug was loaded into hydrogels via a swelling method. DSC was used to study the interactions between the CLB molecules and the polymers. The results indicate that the CLB-polymer interactions are at the molecular level. Loading CLB into these polymers can result in an evident decrease in the glass transition temperature (T(g)), and the variation of T(g) (DeltaT(g)) depends on the structures of the polymers and their beta-CD content. The controlled release experiments show that the presence of beta-CD can markedly enhance CLB release from shrunken PNIPA hydrogels and increase the ratio of CLB released in total drug loading content. Release profile of CLB from hydrogels 1a-c and 4 at pH 1.4 and 7.4, at 37 degrees C.
Gregor Mendel and "Myth-Conceptions"

,entitled“ScientiﬁcMyth-Conceptions”(Allchin,2003), the author aptly criticized “popular histories of science that romanticize scien-tists, inﬂate the drama of their discoveries and cast scientists and the process of sci-ence in monumental proportion” (p. 329). The ﬁrst example cited of such romanticism isGregor Mendel. However, there is also tendency among some historians, such as Monaghanand Corcos (1990) and Di Trocchio (1991), to disparage Mendel’s contributions withclaims that contradict his original writings (Orel, 1996; Orel & Hartl, 1994; Fairbanks& Rytting, 2001). Such is also the case with the depiction of Gregor Mendel in Allchin’sarticle.FollowingtheleadofMonaghanandCorcos(1990),thearticlecreditsMendel’sprincipleof independent assortment not to him but to geneticists who worked several years after therediscovery of his work. It states: “in his classic 1865
Detailed Operating Characteristics Of A 30-Kw Ammonia Arcjet Engine With A Contoured Nozzle

Detailed experimental investigations were conducted to define the operating characteristics of a 30-kW type, arcjet engine with a contoured nozzle. The experiments were conducted in a fully instrumented facility with the engine mounted on a thrust stand. Engine performance was mapped over a power range of 10.6 to 23.0 kW with a mass flow range of 0.175 to 0.350 g/s. The data is presented in graphical form with the relationships between arc potential, arc current, power, thrust, specific impulse and thrust efficiency presented. This paper provides the first detailed accounting of arcjet operation with a contoured nozzle. Further theoretical and experimental work needs to be done to fully explain many of the features exhibited by the data.
Information assimilation research at the University of Michigan for the ARPA unmanned ground vehicle project

The goal of ARPA's Unmanned Ground Vehicle project is to demonstrate the use of small teams of cooperating autonomous robots (2 - 4 vehicles) to carry out military tasks in an outdoor environment. The role of the University of Michigan within the project focuses on aspects of mission planning, assimilation of information provided by multiple agents, and the interaction between planning and perception. The two aspects of this work related to sensor fusion are planning observation points to maximally reduce hypothesis uncertainty, and information sharing in multivehicle scenarios to reduce the amount of perception required. Observation point planning combines the system's current knowledge about an object with the uncertainty model used to characterize observations for data fusion in order to select optimal points for additional observations. Information sharing selects those detected features in the environment which are predicted to be most useful to other cooperating vehicles in the future, adding them to the multiagent system's model of the environment while ignoring less useful features.
Changes in Substance use during the Transition to Adulthood: A Comparison of College Students and Their Noncollege Age Peers

This study examines transitions in alcohol, cigarette, and marijuana use and alcohol- and marijuana-related problems from late adolescence through young adulthood. Men and women who attend college are compared to their peers who do not to determine if the situational/socialization effects of college are unique during this developmental period. Prospective data from a community sample were collected at ages 18, 21, and 30 years. ANOVAs revealed that 18 year olds who transition out of high school, regardless of college status, reported higher levels of substance use than their peers who were still in high school. In addition, nonstudents compared to college students reported higher levels of cigarette and marijuana use in adolescence, emerging adulthood, and young adulthood and higher levels of alcohol- and marijuana-related problems in adolescence and young adulthood. Latent growth curve analyses revealed that college status was related to lower levels of alcohol and marijuana problems at age 18, greater i...
Portraits of Johann Joachim Quantz

The discovery of a hitherto unknown portrait reputedly of Johann Joachim Quantz, prompted the following examination of the known 18th-century portraits of the German musician. Quantz was among the most successful musicians of his time: a distinguished flautist, composer, and author of an important lateBaroque treatise on performance practice, Versuch einer Answeisung die Fl6te transversiere zu spielen (Berlin, 1752). He was born in 1697; from 1718 he served in Dresden (and Warsaw) as an oboist, and later flautist, at the court of the Elector of Saxony and King of Poland, Augustus II (1670-1733) and his successor Augustus III (1696-1763). He is, however, best remembered as the teacher and court musician of Frederick
A clinical study of complete heart block.

Abstract Complete heart block meeting our criteria is uncommon. Arteriosclerotic heart disease was the chief etiologic factor in 90 out of 49,000 patients on whom electrocardiographic studies were made. Overdigitalization was the most frequent toxic cause. The QRS configuration or duration is considered an unreliable index of the position of the pacemaker, since bundle branch block frequently may coexist with complete heart block. Isuprel (isopropyl norepinephrine) was found to be the most useful drug in our series, regardless of the underlying mechanism producing attacks. In only three of our patients was ventricular fibrillation considered the mechanism producing symptoms. The prognosis depends upon the stability of the idioventricular pacemaker, the presence of symptoms, and the underlying mechanism producing attacks. With some exceptions, however, the prognosis of symptomatic complete heart block is generally poor.
IMPACT OF UNLICENSED ASSISTIVE PERSONNEL ON PATIENT SATISFACTION : AN INTEGRATIVE REVIEW OF THE LITERATURE

A literature review was conducted of 16 research articles examining the relationship between implementation of a model of care utilizing unlicensed assistive personnel (UAP) and patient satisfaction. In nine of the articles, the implementation of the UAP model was found to increase patient satisfaction. In seven articles, the implementation of the UAP model was found to have no effect on patient satisfaction. In addition, two research articles also were reviewed that related patient satisfaction to continuity of care and aspects of caring behaviors. Discussion of these articles included research problems, methodology, findings, and conclusions.
The influence of geomagnetic and solar variabilities on lower thermosphere density

Abstract Atmospheric density measurements near 200 km from the Satellite Electrostatic Triaxial Accelerometer (SETA) experiment are analyzed for geomagnetic and solar flux variability effects. Data from the SETA experiment, onboard two satellites, are available for the periods of May to November 1982, and July 1983 to March 1984. The data utilized the span ±79.5° latitude, and are available for both day (1030 LT) and night (2230 LT). Annual and semiannual density variations are removed and regression analyses are performed on the residuals using a series of lagged 3 h K p indices to determine and remove geomagnetic fluctuations. Densities are found to increase by as much as 134% in response to an increase in the K p index from 1 to 6. Monthly curves are generated for the K p regression coefficients to delineate seasonal-latitudinal and day/night dependences, which reflect the effects of mean meridional advection of disturbances from high to low latitudes. Further analyses are performed comparing measured densities with MSISE-90 predictions. Results show that the model is able to capture many of the prominent features, but does not fully predict the level of variability for the individual disturbance periods analyzed. After the geomagnetic effects are removed, the residual densities are interpreted in terms of solar flux variability. The daily-averaged SETA density residuals are strongly correlated with long-term solar flux variability, and exhibit a much greater dependence on the 27-day solar rotation period than MSISE-90 predictions. Variations in residual density of the order of 10–20% occur in association with day-to-day and 27-day solar flux variations. The MSIS model does not accurately predict the magnitude of these short-term density variations in response to solar activity.
Influence of venture capitalists on high tech management

Abstract The use of venture capital to finance high technology firms has increased dramatically in recent years. Venture capitalists often decide which high tech firms will receive financial backing; once financing is approved, they may exercise a great deal of influence on the firm's management. This study investigates the role of the venture capitalist in the management of the high tech firm. A body of literature on institutional power and organizational dependence is used as the theoretical framework for this research. Attention is directed toward the nature of venture capital influence, extent of influence, and factors moderating that influence. Results show that venture capitalists are deeply involved in establishing policies and monitoring managerial activities in high tech firms. The extent of influence is moderated by such factors as stage in the organizational life cycle, size of the venture capitalist, lead position of the venture capitalist, perceived firm performance, and background of entrepreneur.
Kinetic undercooling in solidification of a hypereutectic Al-Si alloy; Effect of solidifying within a ceramic preform composite

Dendrite tip temperature measurements are reported for the hypereutectic alloy Al-30% Si, directionally solidified as a bulk (non-composite) alloy, and also as the matrix of a fibrous metal matrix composite. Over the range of tip velocities studied (10-1000 mu m s) the primary Si tip undercooling in the directionally solidified bulk alloy increases slightly with increasing tip velocity, and indicates, by its large value, the presence of significant kinetic undercooling. This is in contrast with solidification of the composite, in which the primary Si tip undercooling decreases markedly with increasing tip velocity and is in quantitative agreement with theory for cellular solidification with no kinetic undercooling. These results, supported by metallographic observations, indicate that "wetting" of the alumina fibers by the growing silicon phase in the composite essentially eliminates the kinetic barrier to growth of primary Si crystals. The underlying mechanism is rationalized on the basis of macroscopic capillaric analysis at the solid/fiber/liquid juncture. This juncture is shown to be significantly more efficient in nucleating new facet planes than is are-entrant twin plane corner. (C) 1997 Acta Metallurgica Inc.
SU-FF-T-131: Clinical Use of Linear Array MOSFET for Urethral Dose Verification in Prostate High Dose Rate Brachytherapy

Purpose: To investigate the use of linear array MOSFET as in vivo dosimetry detector to determine the urethral dose for a single and multiple fraction during the prostate HDR treatment. Method and Materials: Commercially available Linear Array MOSFETs with 5 individual MOSFET was inserted into the 18 gage Foley catheter right after the HDR prostate implant. Measurements were performed in 25 patients receiving total of 2400cGy HDR boost in 4 fractions with 600cGy per fraction. The urethra dose was measured right after first fraction for all the patients and also subsequent fraction in 5 patients in terms of reproducibility of urethra dose. The exact location of the MOSFET was determined using radio‐opaque marker and the point dose for each MOSFET was determined using CT‐base treatment planning.Results: A Linear Array MOSFETs was placed in such a way that the first MOSFET being slightly above the bladder neck with the average reading of 75%±18% of the prescribed dose since it is beyond the base of the prostate. The dose was increased to maximum of 128% of the total dose within the prostate gland and decreased to 40% or less of the total dose beyond the apex of the gland. There was an excellent correlation of 2.8% between the MOSFET reading and treatment planningdose calculations. The MOSFET reading comparison between first and second fraction also correlated within 2.3%. Conclusion:MOSFETs are suitable for in vivodosimetry during prostate high dose rate brachyhterpy not only to verify the dose across the urethra but also to verify that the needles are maintained in its exact same position as the first fraction. Any unexpected variation in urethra dose compared to initial treatment plan can be corrected in the subsequent fraction as a result of this dose verification procedure.
Convergence and error estimates for finite element solutions of elastohydrodynamic lubrication

Abstract By using a formulation of EHL problems which employs a nonlinear variational inequality and an exterior penalty method, convergence of finite element approximations to the EHL problem is studied. It is shown that the finite element method for the penalized problem is convergent. Then an a priori error estimate of the finite element solution is derived. Numerical experiments are performed for both line contact and point contact problems. In cases of light loads, first-order convergence in the H 1 -norm for pressure approximation by linear elements and second-order convergence for quadratic elements are achieved as predicted. One order higher convergence in the L 2 -norm is also observed as expected.
A reliability test of standard-based quantitative PCR: exogenous vs endogenous standards.

Abstract The quantitative measurement of gene expression requires consistent and reliable standards. At least two categories of standards, endogenous and exogenous, are currently used for quantitative PCR. The reliability of these two methods, however, has not been carefully compared. We hypothesized that a reliable quantitative PCR assay would be able to detect known dilutions of a given single-stranded (ss-) cDNA. By measuring VEGF ss-cDNA copy numbers or signal ratios of GAPDH/VEGF in 10× and 100× diluted samples of two original ss-cDNA preparations, an exogenous recombinant DNA standard (a VEGF-mimic plasmid) and an endogenously expressed GAPDH standard were tested for their ability to detect dilution factors. Using the recombinant DNA standard, the dilution factor was detected as 10·3 and 135·0 in 10× and 100× diluted samples of the original CaSki cell ss-cDNA, respectively. The detected dilution factors were 12·3 and 226·2, respectively, in 10× and 100× diluted ss-cDNA from U-251 MG cells. On the other hand, with the endogenous GAPDH standard, the dilution factors were detected as 2·7 and 8·0 in the same 10× and 100× dilutions of the original U-251 MG cell ss-cDNA. Using the same endogenous GAPDH standard, the detected dilution factors were both 4·8 in 10× and 100× dilutions of the original CaSki cell ss-cDNA. It was also found that the number of endogenous copies of GAPDH mRNA was about 1000 times higher than VEGF. The high internal lockup ratio of GAPDH vs VEGF copy numbers and the requirement for additional primer pairs make the use of an abundant endogenous standard an unreliable choice in quantitative or semi-quantitative PCR. In contrast, exogenous standard-based quantitative PCR was shown to be an accurate and reliable method for the quantitation of gene expression.
Numerical grid methods for quantum-mechanical scattering problems

We show how the finite-element method can be implemented using a discrete variable representation to provide an efficient means for directly solving the time-independent Schr\"odinger equation on a multidimensional numerical grid. For collision problems, an exterior complex scaling transformation obviates the need for explicit imposition of asymptotic boundary conditions, making the method particularly useful for studying three-body breakup. The method is illustrated by studying an analytically solvable two-dimensional (2D) breakup problem as well as a 2D model problem with exponential potentials.
Hepatitis G virus infection in patients with hepatitis C virus infection undergoing liver transplantation

Abstract BACKGROUND & AIMS: Hepatitis G virus (HGV) is transmissible by blood transfusion, but its role in chronic liver disease is unknown. The aim of this study was to determine the prevalence of HGV infection in patients infected with hepatitis C virus (HCV) undergoing transplantation and evaluate the effects of HGV coinfection on the course of posttransplantation HCV infection. METHODS: One hundred twenty-four patients infected with HCV undergoing liver transplantation were studied. Serum samples were tested for HCV and HGV RNA; HCV RNA was quantitated by branched DNA assay, and HCV genotype was determined. RESULTS: The prevalence of pretransplantation and posttransplantation HGV infection was 24% and 28%, respectively. Pre-transplantation HGV infection was positively correlated with posttransplantation HGV infection (P CONCLUSIONS: Although HGV coinfection is frequent in patients with end- stage HCV disease undergoing liver transplantation, there is no association between the presence of HGV coinfection and the severity of liver disease post-transplantation, graft, or patient survival. (Gastroenterology 1996 Dec;111(6):1569-75)
Cumulative response of ecosystem carbon and nitrogen stocks to chronic CO2 exposure in a subtropical oak woodland

Summary Rising atmospheric carbon dioxide (CO2) could alter the carbon (C) and nitrogen (N) content of ecosystems, yet the magnitude of these effects are not well known. We examined C and N budgets of a subtropical woodland after 11 yr of exposure to elevated CO2. We used open-top chambers to manipulate CO2 during regrowth after fire, and measured C, N and tracer 15N in ecosystem components throughout the experiment. Elevated CO2 increased plant C and tended to increase plant N but did not significantly increase whole-system C or N. Elevated CO2 increased soil microbial activity and labile soil C, but more slowly cycling soil C pools tended to decline. Recovery of a long-term 15N tracer indicated that CO2 exposure increased N losses and altered N distribution, with no effect on N inputs. Increased plant C accrual was accompanied by higher soil microbial activity and increased C losses from soil, yielding no statistically detectable effect of elevated CO2 on net ecosystem C uptake. These findings challenge the treatment of terrestrial ecosystems responses to elevated CO2 in current biogeochemical models, where the effect of elevated CO2 on ecosystem C balance is described as enhanced photosynthesis and plant growth with decomposition as a first-order response.
Multiagent Traffic Management: A Reservation-Based Intersection Control Mechanism

Traffic congestion is one of the leading causes of lost productivity and decreased standard of living in urban settings. Recent advances in artificial intelligence suggest vehicle navigation by autonomous agents will be possible in the near future. In this paper, we propose a reservation-based system for alleviating traffic congestion, specifically at intersections, and under the assumption that the cars are controlled by agents. First, we describe a custom simulator that we have created to measure the different delays associated with conducting traffic through an intersection. Second, we specify a precise metric for evaluating the quality of traffic control at an intersection. Using this simulator and this metric, we show that our reservation-based system can perform two to three hundred times better than traffic lights. As a result, it can smoothly handle much heavier traffic conditions. We show that our system very closely approximates an overpass, which is the optimal solution for the problem with which we are dealing.
Nod1 Is an Essential Signal Transducer in Intestinal Epithelial Cells Infected with Bacteria That Avoid Recognition by Toll-Like Receptors

The transcription factor NF-κB in human intestinal epithelial cells plays a central role in regulating genes that govern the onset of mucosal inflammatory responses following intestinal microbial infection. Nod1 is a cytosolic pattern recognition receptor in mammalian cells that senses components of microbial peptidoglycans and signals the activation of NF-κB. The aim of these studies was to assess the functional importance of Nod1 in activating NF-κB and NF-κB proinflammatory target genes in human intestinal epithelium. Human colon epithelial cells that constitutively express Nod1 were used as a model intestinal epithelium. These cells do not signal through Toll-like receptor 4 (TLR4) or respond to bacterial lipopolysaccharide, but they express functional TLR5 and interleukin 1 (IL-1) receptors that signal the activation of NF-κB in response to bacterial flagellin or IL-1 stimulation. Stable expression of dominant negative (DN) Nod1 in colon epithelial cells prevented IκB kinase and NF-κB activation in response to infection with enteroinvasive Escherichia coli. In contrast, DN Nod1 did not eliminate IL-1 or flagellin-stimulated NF-κB activation. Inhibition of NF-κB was accompanied by inhibition of NF-κB target genes that provide signals for the mucosal influx of neutrophils during intestinal infection. We conclude that signaling through Nod1 is required for activating NF-κB in human intestinal epithelial cells infected with gram-negative enteric bacteria that can bypass TLR activation. Signaling through Nod1 provides the intestinal epithelium with a backup mechanism for rapidly activating innate immunity during infection with a group of highly invasive pathogenic gram-negative bacteria.
A new deterministic network reliability measure

We introduce and study properties of a new definition of connectivity and reliability which we call “mean connectivity.” The usual definition of cohesion which is used in survivability or reliability analysis is local in that it is the minimum size of an edge cutset. Mean connectivity involves an average time to connectivity, where the average is over random sequences of the edges of a graph. Aside from intuitive appeal, the new definition is shown to have desirable mathematical properties.
S waves generated by small seismic sources

Observations of S waves from small earthquakes recorded at near distances indicate that the relative S wave generation extends over a wide range. Similar measurements from underground nuclear explosions indicate a ratio of S to P wave generation to be below the observed values for 70 % of the earthquakes studied. The observation of S waves from small events at teleseismic distances is made difficult by interference of microseisms in the period range where S waves may be expected. The observation is also made difficult by the physical requirement that two horizontal component seismographs are required to obtain good resolution of S wave motion. Some measurements have been made at the University of Michigan by means of three-component seismometers in arrays to obtain better resolution of S wave motion. The results of these measurements suggest that improvements in S wave signal/noise ratios similar to those obtained for P waves are possible. The use of S waves from small events at teleseismic distances should not be considered of value as a method of detection. It does, however, offer promise as an added method of identification for small seismic events.
AN EXPERIMENTAL INVESTIGATION OF RESEARCH TOURNAMENTS

I. INTRODUCTION Research tournaments have played an important role in the economic growth of nations since the earliest stages of the Industrial Revolution. For example, the golden age of steam locomotion was spawned by a research tournament sponsored by the Liverpool and Manchester Railway in 1829.(1) More recently, research tournaments have been used to create a variety of products ranging from fuel-efficient refrigerators (Langreth [1994]) and digital televisions (Economist [1993]), to high-tech fighter aircraft for the military (Schwartz et al. [1991]). Today, scientists and lawmakers are even considering the use of a research contest to propel the development of the first manned space mission to Mars.(2) Despite the recurring popularity of research tournaments over the last two hundred years, the first theoretical model for evaluating their efficiency was not published until Taylor's [1995] seminal work. Taylor's model provides a theoretical basis for evaluating the effect the number of competitors and tournament duration have on the amount of effort expended by contestants in a research tournament. Taylor proved that, by limiting the number of competitors in a research tournament and charging each competitor an entry fee, research tournament sponsors can induce an efficient amount of innovative effort. Fullerton and McAfee [1999] extended research tournament theory to include competitions with heterogeneous contestants, showing for a large class of contests the optimal number of competitors is two and sponsors can induce the best qualified competitors to enter the tournament by holding specialized all-pay entry auctions. Although the economic intuition behind these research tournaments is straightforward, the empirical calculations required to compute their equilibrium strategies are very complex, and it is an empirical question as to whether individuals are able to compute these strategies. Therefore, to investigate the predictive power of research tournament models, we conducted a series of laboratory experiments to test Taylor's seminal research tournament theory by examining whether subjects in a controlled economic laboratory setting can be induced to expend the predicted amount of research and development (RD x = 0. Each new innovation is drawn, with recall, from the distribution of innovations allowing each competitor to retain the best draw across all T periods of the tournament. …
Permanent pacemaker requirement after concomitant surgical ablation for atrial fibrillation.

In their recent review of ablation options for atrial fibrillation, Pinho-Gomes et al. [1] omitted permanent pacemaker requirement as a complication of surgical ablation. In their series of 594 patients undergoing concomitant surgical ablation of atrial fibrillation, of whom 6.9% required permanent pacemakers postoperatively, Pecha et al. [2] identified biatrial lesion sets as a statistically significant risk factor for permanent pacemaker insertion after surgical ablation, confirming the findings of Soni et al. [3] in their series of 305 patients. We analysed 17 983 patients undergoing valve surgery with concomitant ablation identified from the Nationwide Inpatient Sample between 2002 and 2010. This administrative database is sponsored by the Agency for Healthcare Research and Quality, and contains information on all inpatient episodes in approximately one-fifth of US hospitals selected to provide a representative sample of national practice: the individual hospitals sampled vary each year. Pacemakers were implanted in 6.9% of patients undergoing valve surgery. After adjusting for baseline patient comorbidity, concomitant ablation procedure [odds ratio (OR) 1.31, 95% confidence interval (CI) 1.27–1.41] was one of the main independent predictors of permanent pacemaker implantation in patients undergoing valve surgery. In patients undergoing ablation, valve procedures associated with the greatest risk of permanent pacemaker requirement were mitral replacement (OR 1.37, 95% CI 1.2–1.67) and combined mitral replacement and tricuspid valve surgery (OR 1.79, 95% CI 1.69– 2.77) (isolated aortic valve replacement was used as the reference). Mitral repair was less likely to result in permanent pacemaker (OR 0.84, 95% CI 0.72–0.98), unless concomitant tricuspid surgery was undertaken (OR 1.79, 95% CI 1.37–2.33). These surgical predictors of permanent pacemaker requirement are consistent with data from a previous single-centre series [4], and the overall incidence of pacemaker insertion we observed is similar to that reported in an analysis of the Society of Thoracic Surgeons database [5]. The main limitation of the Nationwide Inpatient Sample in this context is that it does not provide information on the ablation lesion sets employed, or provide sufficient data to adjust for other potential confounding variables. However, this analysis indicates that patients undergoing concomitant surgical ablation at the time of valve surgery have a significantly increased risk of postoperative permanent pacemaker requirement in comparison with those who do not undergo concomitant ablation.
Biometric score fusion through discriminative training

In the multibiometric systems, various matcher/modality scores are fused together to provide better performance than the individual matcher scores. In [1] the authors have proposed a likelihood ratio test (LRT) based fusion technique for the biometric verification task that outperformed several other classifiers. They model the genuine and the imposter densities by the finite Gaussian mixture models (GMM, a generative model) whose parameters are estimated using the maximum likelihood (ML) criteria. Lately, the discriminative training methods and models have been shown to provide additional accuracy gains over the generative models, in multiple applications such as the speech recognition, verification and text analytics[5, 7]. These gains are based on the fact that the discriminative models are able to partially compensate for the unavoidable mismatch, which is always present between the specified statistical model (GMM in this case) and the true distribution of the data which is unknown. In this paper, we propose to use a discriminative method to estimate the GMM density parameters using the maximum accept and reject (MARS) criteria[8]. The test results using the proposed method on the NIST-BSSRI multimodal dataset indicate improved verification performance over a very competitive maximum likelihood (ML) trained system proposed in [1].
Teachers' Experiences with Inclusive Classrooms: Implications for Special Education Reform

Teachers completed a survey of attitudes toward several basic assumptions regarding inclusion of children with mild disabilities; perceptions of self-efficacy, competence, and teaching satisfaction; and judgments of the appropriateness of classroom adaptations. Respondents included 185 regular education teachers in traditional classrooms, and 71 regular education and 64 special education teachers who co-taught children in inclusive classrooms. Special education teachers held the most positive views of inclusion, as well as the highest perceptions of self-efficacy, competency, and satisfaction. Regular education teachers in the inclusive classrooms tended to report views similar to those of their special education counterparts. Regular classroom teachers in traditional classrooms held the least positive perceptions in these areas and viewed classroom adaptations as less feasible and less frequently used than did teachers in those classrooms in which the “protected resource” of two teachers was provided. Te...