cssi/SciSciGPT-SciSciNet huggingface dataset:
Fabric structure and mold curvature effects on preform permeability and mold filling in the RTM process. Part I. Experiments

Abstract Liquid composite molding (LCM) processes require the impregnation of a polymeric resin through a porous preform, being composed of glass, carbon, or kevlar fibers. The successful manufacture of composite parts through these methods is dependent on the successful filling of the mold cavity, expelling all air from within. Numerical simulations are being developed to model this process, and are powerful mold design tools. The accuracy of such simulations is strongly dependent on the specification of the preform permeability tensor throughout the mold cavity, being a numerical description of the resistance to resin flow. Changes in preform architecture can easily modify local permeability, and hence the mold filling. Corners in mold cavities are a potential sites for preform deformation, and are the focus of this study. A family of five molds have been studied, containing corner radii from 0.06 to 8.0 in. A detailed flow visualization study has been completed to investigate the influence of mold corner radii on flow front progression and injection pressure. While flow front progression was not significantly affected by different corner radii, injection pressures were found to be greater for the molds with smaller corner radii. Actual composite parts manufactured in the same molds have revealed that the molds are not of constant cavity thickness, as was the original goal. To determine the importance of corner radii on mold filling, it will be necessary to separate the effects of in-plane preform compression from any effect due to corners. To accomplish this goal, the experimental data presented here is being compared with detailed numerical studies, which will be presented in part II of this work.
The economic and law of rent control

What stirs most people against rent control laws in the United States and elsewhere are stories of people who have held apartments for many years and now pay absurdly low rents for them. There are important reasons for removing rent controls, but the shock value of a low rent is not one of them. Basu and Emerson construct a model of second-generation rent control, describing a regime that does not permit rent increases for sitting tenants - or their eviction. When an apartment becomes vacant, however, the landlord is free to negotiate a new contract with a higher rent. They argue that this stylized system is a good (though polar) approximation of rent control regimes that exist in many cities in India, the United States, and elsewhere. Under such a regime, if inflation exists, landlords prefer to rent to tenants who plan to stay only a short time. The authors assume that there are different types of tenants (where type refers to the amount of time tenants stay in an apartment) and that landlords are unable to determine types before they rent to a tenant. Contracts contingent on departure date are forbidden, so a problem of adverse selection arises. Short stayers are harmed by rent control while long-term tenants benefit. In addition, the equilibrium is Pareto inefficient. Basu and Emerson show that when tenant types are determined endogenously (when a tenant decides how long to stay in one place based on market signals) in the presence of rent control, there may be multiple equilibria, with one equilibrium Pareto-dominated by another. In other words, many lifestyle choices are made based on conditions in the rental housing market. One thing rent control may do is decrease the mobility of the labor force, because tenants may choose to remain in a city where they occupy rent-controlled apartments rather than accept a higher-paying job in another city. Basu and Emerson show that abolishing the rent control regime can do two things: Shift the equilibrium to a better outcome and result in lower rents, across the board. A version of this paper - a product of the Office of the Senior Vice President and Chief Economist, Development Economics - was presented at an Applied Microeconomics Workshop at Cornell University.
ASSESSMENT OF HYPOTHALAMO-ANTERIOR PITUITARY SECRETING CAPACITY IN CHILDREN ON THE BASIS OF A SINGLE TEST

A combination of insulin hypoglycemia with administration of the recently synthesised releasing hormones TRH and LH-RH allows almost complete evaluation of the anterior pituitary function in one single test. The combined test was performed in over 60 children with suspected hypothalamo-pituitary disorders. Insulin (0,1 U/kg) was injected intravenously followed by TRH (200 ug) followed by LH-RH (100 ug). Growtn hormone, ACTH, LH, FSH, TSH and cortisol were measured by radibimmunoassay and blood sugar by an enzymatic technique. The assays were shown to be specific and there were no cross reactions between the different hormones assayed. The normal response to insulin hypoglycemia is not altered by simultaneous injection of the releasing hormones. Similarly the TSH-response to TRH alone does not differ from that observed during a combined test. The combined test has proved to be useful for the differential diagnosis of short stature in children and various disorders of suspected pituitary hypothalamic origin. The diagnosis of an isolated or combined hormone deficiency can thus be made on the basis of a single test.
Testing ice microphysics parameterizations in the NCAR Community Atmospheric Model Version 3 using Tropical Warm Pool-International Cloud Experiment data

[1] Cloud properties have been simulated with a new double-moment microphysics scheme under the framework of the single-column version of NCAR Community Atmospheric Model version 3 (CAM3). For comparison, the same simulation was made with the standard single-moment microphysics scheme of CAM3. Results from both simulations compared favorably with observations during the Tropical Warm Pool–International Cloud Experiment by the U.S. Department of Energy Atmospheric Radiation Measurement Program in terms of the temporal variation and vertical distribution of cloud fraction and cloud condensate. Major differences between the two simulations are in the magnitude and distribution of ice water content within the mixed-phase cloud during the monsoon period, though the total frozen water (snow plus ice) contents are similar. The ice mass content in the mixed-phase cloud from the new scheme is larger than that from the standard scheme, and ice water content extends 2 km further downward, which is in better agreement with observations. The dependence of the frozen water mass fraction on temperature from the new scheme is also in better agreement with available observations. Outgoing longwave radiation (OLR) at the top of the atmosphere (TOA) from the simulation with the new scheme is, in general, larger than that with the standard scheme, while the surface downward longwave radiation is similar. Sensitivity tests suggest that different treatments of the ice crystal effective radius contribute significantly to the difference in the calculations of TOA OLR, in addition to cloud water path. Numerical experiments show that cloud properties in the new scheme can respond reasonably to changes in the concentration of aerosols and emphasize the importance of correctly simulating aerosol effects in climate models for aerosol-cloud interactions. Further evaluation, especially for ice cloud properties based on in situ data, is needed.
Crystal structures of penicillin-binding protein 6 from Escherichia coli.

Penicillin-binding protein 6 (PBP6) is one of the two main dd-carboxypeptidases in Escherichia coli, which are implicated in maturation of bacterial cell wall and formation of cell shape. Here, we report the first X-ray crystal structures of PBP6, capturing its apo state (2.1 A), an acyl-enzyme intermediate with the antibiotic ampicillin (1.8 A), and for the first time for a PBP, a preacylation complex (a “Michaelis complex”, determined at 1.8 A) with a peptidoglycan substrate fragment containing the full pentapeptide, NAM-(l-Ala-d-isoGlu-l-Lys-d-Ala-d-Ala). These structures illuminate the molecular interactions essential for ligand recognition and catalysis by dd-carboxypeptidases, and suggest a coupling of conformational flexibility of active site loops to the reaction coordinate. The substrate fragment complex structure, in particular, provides templates for models of cell wall recognition by PBPs, as well as substantiating evidence for the molecular mimicry by β-lactam antibiotics of the peptidoglycan...
Utilization of Pay-in Antenatal Leave Among Working Women in Southern California

Objectives: Examine antenatal leave arrangements among pregnant workers in California, and the occupational, demographic and well-being characteristics associated with leave taking. Unlike most states, California provides paid pregnancy leave up to 4 weeks antenatally and 6–8 weeks postnatally. Methods: Weighted data from postpartum telephone interviews conducted between July 2002 and November 2003 were analyzed for 1214 women participating in a case–control study of birth outcomes in Southern California. Eligible women worked at least 20 h/week during the first two trimesters of pregnancy or through the date of prenatal screening. The overall response rate was 73%. Results: Fifty-two percent of women took no leave, 32% took antenatal leave expecting to return to their job or employer sometime after giving birth, and 9% quit their jobs during pregnancy. For leave-takers with paid leave (69%), the state was the main source of pay (74%). Medical problems (52%) rather than maternity leave benefits (25%) were the most common stated reasons for taking leave. The strongest predictors of leave taking versus working through pregnancy were feeling stressed and tired (adjusted OR = 4.3, 95% CI [2.2–8.2]) and having young children (adjusted OR = 2.1, 95% CI [1.2–3.7]), followed by occupational factors (night shift, unfulfilling and inflexible work, short work tenure). Lack of employer-offered maternity leave benefits was associated with increased quitting relative to both leave taking and working through pregnancy. Conclusions: Maternity benefits influence quitting, but alone do not determine antenatal leave taking. Working pregnant women in California utilize leave cautiously and predominantly to cope with health problems, work dissatisfaction and fatigue.
The Akamai approach to achieving performance and reliability on the internet

In this talk, we will describe several issues that impact the performance, reliability, and security of dynamic applications running over the Internet. We will then describe some of the techniques used by Akamai to overcome these problems, as well as six basic design principles for achieving reliability in a large-scale, distributed, real-time system operating in an unreliable environment such as the Internet. The talk will be introductory in nature.
Constraints on the Calibration of Performance

Abstract We examined the effect of experimenter-controlled incentives and feedback on the calibration of performance. Subjects answered 36 reading comprehension and 8 mathematical multiple-choice questions and rated the accuracy of their responses. Perfect calibration was possible only when true and estimated test performance were approximately equal. Incentives for improved performance (i.e., doubling the credit people received for correct answers) adversely affected performance and calibration compared to the same incentives for improved calibration (i.e., doubling credit for minimizing the error between true and estimated performance). Feedback had no effect on performance or accuracy nor did it interact with the incentive variable. An examination of coefficient α suggested a strong response bias by individuals when calibrating their performance; individuals tended to rate their performance accuracy consistently regardless of item difficulty or whether they answered the item correctly. Educational implications were discussed.
The utility of cytopathology testing in lung transplant recipients.

Background Lung transplant recipients routinely undergo bronchoscopy, during which bronchoalveolar lavage (BAL) fluid and transbronchial biopsies are usually obtained. These specimens are typically sent for microbiology, histopathology and cytopathology testing. Cytopathology testing is expensive, and its diagnostic value is questionable. We hypothesized that cytopathology specimens have no additional diagnostic yield beyond that of microbiology and histopathology testing in the routine care of our lung transplant patients. Methods We reviewed all bronchoscopies performed on a cohort of patients who underwent lung transplantation between February 1999 and August 2002 at our institution. Demographic data, immunosuppressive therapy and the incidence of opportunistic infections in this cohort of 65 patients were reviewed. To ascertain the diagnostic value of cytopathology testing, microbiology and histopathology results from bronchoalveolar lavage and transbronchial biopsy tests were compared with cytopathology results. Results Three hundred sixty-six bronchoscopies were reviewed. Microbiologic and histopathology identified 51 cytomegalovirus-, 157 fungus- and 13 mycobacteria-positive specimens as well as respiratory syncitial virus, influenza A and B, enterovirus, actinomyces, Nocardia and mycoplasma. Cytopathology of BAL fluid identified only 3 cytomegalovirus- and 13 fungus-positive specimens. The only unique diagnoses made by cytopathology were 1 case of Aspergillus and 1 unidentifiable fungal element. Conclusions We conclude that routine cytopathology testing has little additive diagnostic value in bronchoscopic specimens from lung transplant recipients. Cytopathology results did not alter patient management in any of our 366 cases. Centers should consider discontinuing routine use of cytopathology testing of BAL fluid for surveillance or clinically indicated bronchoscopy, because the yield of this expensive test is extremely low in the setting of lung transplantation.
AN OPTIMAL MISTING METHOD FOR COOLING LIVESTOCK HOUSING

ABSTRACT The stress ratio (K) used in Janssen's equation for calculating grain pressure was determined for soybeans by four different methods. Static stresses were measured in a 0.91 m diameter x 2.743 m high model galvanized smooth steel bin. The four methods were: 1) measure vertical loads on the floor and wall separately; 2) measure vertical and hoop strains in the bin walls with six, two-element, rosette gages evenly spaced around the bin circumference at 15.2 cm above floor, 3) measure horizontal and shear loads at the bin wall with three ring load cells placed at different heights on the model bin wall (15.2, 61.0, and 106.7 cm above the floor); and 4) directly measure vertical and horizontal stresses within the grain mass using in-mass transducers (IMTs) at four different heights at the bin center (15.2, 61.0, 106.7, and 152.4 cm above the floor). A total of 18 replications were performed. For grain depths less than H/D = 2.8, K-ratio decreased with increasing depth of soybeans. At depths about three times the bin diameter (U/D = 3.0), the K-ratio approached a constant value that may be approximated by KQ = 1 - sin p, where p is the angle of internal friction of grain to grain.
Catherine of Siena's wisdom on discernment and her reception of Scripture

Catherine of Siena’s wisdom on discernment represents a significant development in the history of this essential Christian theme. Her teaching is the fruit of personal wisdom rather than formal study as she was an uneducated lay woman in fourteenth century Italy. In this article I show how Scripture was central to Catherine’s wisdom. First I show that she was exposed to Scripture primarily orally and that she assimilated what she heard through her life of prayer and relationship with God. I describe the central biblical themes at the heart of her teaching on discernment, namely growth in charity and capacity for truth, and I show how these are related to her wisdom on discernment. I then examine how Catherine applied her teaching through an analysis of a letter to Pope Gregory XI.
An Analysis of Convectively Coupled Kelvin Waves in 20 WCRP CMIP3 Global Coupled Climate Models

Abstract Output from 20 coupled global climate models is analyzed to determine whether convectively coupled Kelvin waves exist in the models, and, if so, how their horizontal and vertical structures compare to observations. Model data are obtained from the World Climate Research Program’s (WCRP’s) Coupled Model Intercomparison Project phase 3 (CMIP3) multimodel dataset. Ten of the 20 models contain spectral peaks in precipitation in the Kelvin wave band, and, of these 10, only 5 contain wave activity distributions and three-dimensional wave structures that resemble the observations. Thus, the majority (75%) of the global climate models surveyed do not accurately represent convectively coupled Kelvin waves, one of the primary sources of submonthly zonally propagating variability in the tropics. The primary feature common to the five successful models is the convective parameterization. Three of the five models use the Tiedtke–Nordeng convective scheme, while the other two utilize the Pan and Randall scheme...
Marco Polo: International Marketing Pioneer:

Marco Polo’s Travels is an account of a journey he made with his father and uncle to the court of Mongol emperor Kublai Khan. As such, it has long been recognized as one of the world’s great travel...
Helicity flip in exclusive deep-inelastic ϱ0 production

Abstract The European Muon Collaboration reports that in exclusive ϱ 0 production in deep-inelastic muon scattering from hydrogen and nitrogen targets, the ϱ 0 is found predominately in a longitudinally polarised state. The t -dependence is typical of a hard scattering process. The ϱ 0 's are claimed to be mainly produced by transverse photons. The cross section decreases as ( Q 2 ) −2 . While the latter is expected in a vector dominance model, the dominance of helicity flip is inconsistent with such a model. We show that it is possible to reconcile these experimental results in a simple hard scattering model. However, we must suppose the photons mainly longitudinal, in agreement with Donnachie and Landshoff.
Triangle, Parallelogram, and Trapezoid Orders

In his 1998 paper, Ryan classified the sets of unit, proper, and plain trapezoid and parallelogram orders. We extend this classification to include unit, proper, and plain triangle orders. We prove that there are 20 combinations of these properties that give rise to distinct classes of ordered sets, and order these classes by containment.
The representer method for two-phase flow in porous media

The representer method is applied to a one-dimensional two-phase flow model in porous media; capillary pressure and gravity are neglected. The Euler–Lagrange equations must be linearized, and one such linearization is presented here. The representer method is applied to the linear system iteratively until convergence, though a rigorous proof of convergence is out of reach. The linearization chosen is easy to calculate but does not converge for certain weights; however, a simple damping restores convergence at the cost of extra iterations. Numerical experiments are performed that illustrate the method, and quick comparison to the ensemble Kalman smoother is made.
Plate Heat Exchanger Adsorber for a Regenerative Adsorption Heat Pump

The state of the art in regenerative adsorption (solid-vapor) heat pumps achieved to date is a maximum Coefficient of Performance for Cooling (COPC ) of 1.1 with 70% regeneration of waste heat. A number of configurations for the heat exchanger within the adsorbent bed have been investigated, including concentric tube, shell and tube, serpentine flat pipe, spiral flat pipe, and single-pass plate type. However, to date, compact (or multiple pass plate) heat exchangers for use with adsorbent beds have not been studied. This investigation explains the challenges involved in this application, and describes the design and analysis of three configurations of a compact heat exchanger for use with solid adsorbent. The prinicipal figure of merit affecting both coefficient of performance, COPC , and specific cooling power, SCP (W cooling per kg adsorbent), is defined as NTU divided by the ratio of non-adsorbent (“dead”) to adsorbent (“live”) thermal masses. The best of the three configurations consists of thin adsorbent (zeolite) tiles epoxied to the heat exchanger plates (sheets) with screen wire pin fins in the oil passages to enhance heat transfer.Copyright © 2004 by ASME
Prior killing experience and the suppressive effects of punishment on the killing of mice by rats.

Summary The effect of punishment on mouse-killing by rats was studied in 20 rats that had only the minimum killing experience necessary to show that they were reliable killers, and 20 rats that were given more extensive killing experience before punishment. Half of the rats in each group were presented 1·0 ma shocks contingent upon killing and the others were punished with 2·0 ma shocks. After punishment the rats underwent recovery tests. Punishment suppressed killing in all 4 groups, and the experienced killers continued to kill longer after the institution of punishment and resumed killing sooner after punishment was discontinued than did relatively inexperienced killers. Neither the effect of punishment intensity nor the intensity × experience interaction was statistically significant.
Definition of Two Angiogenic Pathways by Distinct αv Integrins

Angiogenesis depends on cytokines and vascular cell adhesion events. Two cytokine-dependent pathways of angiogenesis were shown to exist and were defined by their dependency on distinct vascular cell integrins. In vivo angiogenesis in corneal or chorioallantoic membrane models induced by basic fibroblast growth factor or by tumor necrosis factor-α depended on α v β 3 , whereas angiogenesis initiated by vascular endothelial growth factor, transforming growth factor-α, or phorbol ester depended on α v β 5 . Antibody to each integrin selectively blocked one of these pathways, and a cyclic peptide antagonist of both integrins blocked angiogenesis stimulated by each cytokine tested. These pathways are further distinguished by their sensitivity to calphostin C, an inhibitor of protein kinase C that blocked angiogenesis potentiated by α v β 5 but not by α v β 3 .
Distribution and particle properties of the vacuolar apparatus of cardiac muscle tissue. I. Biochemical characterization of cardiac muscle lysosomes and the isolation and characterization of acid, neutral and alkaline proteases.

Five acid hydrolases were used to characterize cardiac tissue lysosomes by sedimentation characteristics of the particles, structure-linked latency of the enzymes, and optimum enzyme activity in the acid range. In addition, three cardiac proteases were isolated and partially characterized. Acid protease, pH 3.8, displayed 45% latency, was sedimentable at 50 000 g-min; had three isoenzymes with apparent mol. wt. 58 000, 23 000 and 20 000; Km = 0.86 g% and Vmax = 3.0 × 10−2min−1; was activated by mercaptoethylamine and slightly inhibited by iodoacetic acid. Neutral protease: studied at pH 7.4, had characteristics of a loosely bound membrane enzyme, being 85% free; had a bimodal distribution sedimenting with organelles at 50 000 g-min and 3 420 000 g-min; had three isoenzymes with mol. wit. 60 000, 18 000 and about 8000; Km = 0.86 g% and Vmax = 3.2 × 10−3min−1; was activated by cysteine and inhibited by dithiothreitol and iodoacetic acid. Alkaline protease: studied at pH 8.5, resembled neutral protease in distribution; was 93% free, had three isoenzymes with mol. wt. 60 000, 14 000, and about 7000; Km = 0.76 g% and Vmax = 1.63 × 10−3min−1; was activated by cysteine and inhibited by dithiothreitol and iodoacetic acid. Autolysis increased as pH increased, peaking at pH 8.5. Lipofuscin granules were isolated from rat heart and were shown to contain the following acid hydrolases: acid phosphatase, cathepsin D, β-glucuronidase, and aryl sulphatase.
Postoperative patient-controlled analgesia: Meta-analyses of initial randomized control trials

Abstract Study Objective : To compare outcomes during conventional analgesia (as-needed intramuscular dosing) and patient-controlled analgesia (PCA) in postoperative patients by analyzing data from published comparative trials. Design : Meta-analyses of 15 randomized control trials. Patients : Seven hundred eighty-seven adult patients (aged 16 to 65) undergoing various operative procedures. Interventions : Either PCA or conventional analgesia for postoperative pain control. Measurements and Main Results : Data were extracted on analgesic efficacy, analgesic use, patient satisfaction, length of hospital stay, and side effects. Meta-analyses of the data showed the following: (1) greater analgesic efficacy when PCA was used, with a mean additional benefit of 5.6 on a scale of 0 to 100 (SED, 2.2; p = 0.006); (2) a nonsignificant trend toward reduced analgesic use in PCA patients, based on a count of trials finding in one direction or the other ( p = 0.092); (3) a 42% difference in the proportion of patients expressing satisfaction over dissatisfaction (SED, 20%; p = 0.02), with PCA being preferred; (4) a nonsignificant trend toward shortening of length of hospital stay with PCA use (mean, 0.15 days, SED, 0.13; p = 0.24); (5) no significant differences in the occurrence of any side effect. Conclusions : Patient preference strongly favors PCA over conventional analgesia. Patients using PCA also obtain better pain relief than those using conventional analgesia, without an increase in side effects. Favorable effects of PCA upon analgesic usage and length of hospital stay did not in the initial trials attain statistical significance. Nonetheless, the favorable trends in the mean effect sizes for both outcomes argue that further studies of both outcomes should be performed to determine whether the favorable impact of PCA upon either may become statistically significant if larger numbers of patients are enrolled.
Design and fabrication of freeform glass concentrating mirrors using a high volume thermal slumping process

Abstract Concentrated photovoltaics (CPV) power is a form of clean and renewable energy. However, the cost of harvesting solar energy is still economically prohibitive as compared to more traditional electricity generation methods such as hydroelectric or fossil fuel power. In this study, an innovative, high volume but low cost thermal slumping process was proposed as an alternative method for manufacturing of glass mirrors for high concentration photovoltaic system. In this paper, first a freeform optical design was performed to create a two-stage concentrator with ±1° acceptance angle and uniform output irradiance. Ray-tracing simulation was performed to evaluate the optical design. A machinable ceramic, MACOR®, was tested as mold material for its preferred mechanical and chemical stability at high temperature conditions. To assist the development of the slumping process, finite element method (FEM) simulation was performed to compensate for the mold design for manufacturing errors in this process. Moreover, surface profile and surface roughness were measured to characterize the thermal slumping process. Different manufacturing parameters were tested to identify the proper slumping conditions. It is discovered that surface roughness of the inner surface of the slumped glass mirror remained unchanged after slumping under a pre-determined soaking temperature. This study established a methodology for low cost, high volume glass optics for possible solar concentrator applications.
Kin recognition within a seed and the effect of genetic relatedness of an endosperm to its compatriot embryo on maize seed development

As one of two sexual products resulting from double fertilization in angiosperms, the endosperm nourishes its compatriot embryo during seed development and/or germination and ultimately dies. Theoretical studies suggest that the genetic relatedness of an endosperm to its embryo in the same seed might determine the amount of resources ultimately available for the embryo during seed development. We took advantage of the phenomenon of heterofertilization in cultivated maize to empirically test whether genetic relatedness between a triploid embryo-nourishing endosperm and its compatriot diploid embryo impacts the process of resource allocation between these two sexually produced entities. We used genetically distinct maize inbred lines to perform two crossing experiments. Dry weights of dissected embryos and endosperms of mature heterofertilized and adjacent homofertilized kernels were compared. Embryo weight of heterofertilized kernels was significantly less than that of embryos of homofertilized kernels, whereas there was no significant difference in endosperm weight between the two types of kernels. Our results suggest that the degree of genetic relatedness of an endosperm to its compatriot embryo affects seed development and specifically the amount of maternal resources allocated to an endosperm that are eventually turned over to an embryo. The lower the coefficient of relatedness of an endosperm to its compatriot embryo, the smaller the embryo. Thus, the endosperm of a heterofertilized seed appears to behave less cooperatively with respect to resource transfer toward its less closely related embryo compared with the endosperm of a homofertilized seed.
Detection and Recognition of Photographic Detail. I. Empirical Data Applicable to the Prediction of Performance of Diffraction Limited Systems

Empirical data on visual detection and recognition of photographic detail as recorded on the photographic negative are presented in terms of sizes and contrasts in the object space. The performance of diffraction limited systems is given for five emulsions.
A miRNA Signature of Chemoresistant Mesenchymal Phenotype Identifies Novel Molecular Targets Associated with Advanced Pancreatic Cancer

In this study a microRNA (miRNA) signature was identified in a gemcitabine resistant pancreatic ductal adenocarcinoma (PDAC) cell line model (BxPC3-GZR) and this signature was further examined in advanced PDAC tumor specimens from The Cancer Genome Atlas (TCGA) database. BxPC3-GZR showed a mesenchymal phenotype, expressed high levels of CD44 and showed a highly significant deregulation of 17 miRNAs. Based on relevance to cancer, a seven-miRNA signature (miR-100, miR-125b, miR-155, miR-21, miR-205, miR-27b and miR-455-3p) was selected for further studies. A strong correlation was observed for six of the seven miRNAs in 43 advanced tumor specimens compared to normal pancreas tissue. To assess the functional relevance we initially focused on miRNA-125b, which is over-expressed in both the BxPC3-GZR model and advanced PDAC tumor specimens. Knockdown of miRNA-125b in BxPC3-GZR and Panc-1 cells caused a partial reversal of the mesenchymal phenotype and enhanced response to gemcitabine. Moreover, RNA-seq data from each of 40 advanced PDAC tumor specimens from the TCGA data base indicate a negative correlation between expression of miRNA-125b and five of six potential target genes (BAP1, BBC3, NEU1, BCL2, STARD13). Thus far, two of these target genes, BBC3 and NEU1, that are tumor suppressor genes but not yet studied in PDAC, appear to be functional targets of miR-125b since knockdown of miR125b caused their up regulation. These miRNAs and their molecular targets may serve as targets to enhance sensitivity to chemotherapy and reduce metastatic spread.
Stoichiometry, herbivory and competition for nutrients: simple models based on planktonic ecosystems.

Abstract Models are examined in which two prey species compete for two nutrient resources, and are preyed upon by a predator that recycles both nutrients. Two factors determine the effective relative supply of the nutrients, hence competitive outcomes: the external nutrient supply ratio, and the relative recycling of the two nutrients within the system. This second factor is governed by predator stoichiometry — its relative requirements for nutrients in its own biomass. A model with nutrient resources that are essential for the competing prey is detailed. Criteria are given to identify the limiting nutrient for a food chain of one competitor with the predator. Increased supply of this limiting nutrient increases predator density and concentration of this nutrient at equilibrium, while decreasing the concentration of a non-limiting nutrient. Changes in supply or recycling of a non-limiting nutrient affect only the concentration of that nutrient. Criteria for the invasion of a second prey competitor are presented. When different nutrients limit growth of the resident prey and the invader, increased supply or recycling of the invader's limiting nutrient assists invasion, while increased supply or recycling of the resident's limiting nutrient hinders invasion. If the same nutrient limits both resident and invader, then changes in supply and recycling have complex effects on invasion, depending on species properties. In a parameterized model of a planktonic ecosystem, green algae and cyanobacteria coexist over a wide range of nitrogen:phosphorus supply ratios, without predators. When the herbivore Daphnia is added, coexistence is eliminated or greatly restricted, and green algae dominate over a wide range of supply conditions, because the effective supply of P is greatly reduced as Daphnia rapidly recycles N.
Thermodynamic and kinetic analysis using AB initio calculations on dimethyl-ether radical+O2 reaction system

Reaction pathways and kinetics are analyzed on CH3OC·H2+O2 reaction system using ab initio calculations to determine tehrmodynamic properties of reactants, intermediate radicals, and transitionstate (TS) compounds. Enthalpies of formation (ΔHf298o) are determined using the CBS-q//MP2(full)/6-31G(d,p) method with isodesmic reactions. Entropies (S298o) and heat capacities (Cp(T) 300≤T/K≤1500) are determined using geometric parameters and vibrational frequencies obtained at the MP2(full)/6-31G(d,p) level of theory. Quantum Rice-Ramsperger-Kassel (QRRK) analysis is used to calculated energy-dependent rate constants, k(E), and the master equations is used to account for collisional stabilization. The dimethyl-ether radical CH3OC·H2 (ΔHf298o=0.1 kcal/mol) adds to O2 to form a peroxy radical CH3OCH2OO·(ΔHf298o=−33.9 kcal/mol). The peroxy radical can undergo dissociation back to reactants or isomerize via hydrogen shift (Ea,rxn=17.7 kcal/mol) to form a hydroperoxy alkyl radical C·H2OCH2OOH, (ΔHf298o=−26.5 kcal/mol). This alkyl radical can undergo β-scission reaction to formaldehyde (CH2O)+hydroperoxy methyl radical (C·H2OOH), (Ea, rxn=24.7 kcal/mol). The hydroperoxy methyl radical rapidly decomposes to a second CH2O plus OH. The reaction barriers for CH3OCH2 +O2 to 2 CH2O+OH are lower than the energy needed for reaction back to CH3OC·H2+O2, and provide a low-energy chain propagation path for dimethyl-ether oxidation. O H + C H 3 O C H 3 → C H 3 O C ⋅ H 2 + H 2 O ( 1 ) + ) C H 3 O C ⋅ H 2 + O 2 → 2 C H 2 O + O H ¯ ( 2 ) C H 3 O C H 3 + O 2 → 2 C H 2 O + H 2 O Comparison of calculated falloff with experiment indicates that the CBS-q calculated Ea, rxn for the TS of C·H2OCH2OOH→C·H2OOH+CH2O needs to be lowered in order to match the data of Sehested et al. Rate constants of important reactions are (k=A(T/K) exp(−Ea/RT}), A in cm3/(mol s), EA in kcal/mol): k1, (2.33×1063)(T/K)−16.89e−11.89/RT for CH3OC·H2+O2⇒CH3OCH2OO·; k3, (T/K)−5.46e−8.59/RT for CH3OC·H2+O2⇒CH2O+CH2O+OH at 1 atm..gif">
Public policy implications of an ethnically diverse elderly population

Social, economic, and health care trends demonstrating the rapid growth and diversity of elderly minority and ethnic groups have long-term repercussions for social support service systems in the United States. Current public policies designed for a homogeneous elderly population must become more flexible and must recognize and accommodate the needs of an increasingly diverse American society.
Endocannabinoids in Alzheimer's disease and their impact on normative cognitive performance: a case-control and cohort study.

Background Neuropathological, animal, and cell culture studies point to a role for the body's own endogenous cannabinoids (eCBs) system in Alzheimer's disease (AD) pathology and treatment. To date, no published studies have investigated the potential utility of circulating eCBs as diagnostic biomarkers for AD or the impact of central eCBs on cognition.
Mode of occurrence and environmental mobility of oil-field radioactive material at US Geological Survey research site B, Osage-Skiatook Project, northeastern Oklahoma

Abstract Two samples of produced-water collected from a storage tank at US Geological Survey research site B, near Skiatook Lake in northeastern Oklahoma, have activity concentrations of dissolved 226 Ra and 228 Ra that are about 1500 disintegrations/min/L (dpm/L). Produced-water also contains minor amounts of small (5–50 μm) suspended grains of Ra-bearing BaSO 4 (barite). Precipitation of radioactive barite scale in the storage tank is probably hindered by low concentrations of dissolved SO 4 (2.5 mg/L) in the produced-water. Sediments in a storage pit used to temporarily collect releases of produced-water have marginally elevated concentrations of “excess” Ra (several dpm/g), that are 15–65% above natural background values. Tank and pit waters are chemically oversaturated with barite, and some small (2–20 μm) barite grains observed in the pit sediments could be transferred from the tank or formed in place. Measurements of the concentrations of Ba and excess Ra isotopes in the pit sediments show variations with depth that are consistent with relatively uniform deposition and progressive burial of an insoluble Ra-bearing host (barite?). The short-lived 228 Ra isotope (half-life = 5.76 a) shows greater reductions with depth than 226 Ra (half-life = 1600 a), that are likely explained by radioactive decay. The 228 Ra/ 226 Ra activity ratio of excess Ra in uppermost pit sediments (1.13–1.17) is close to the ratio measured in the samples of produced-water (0.97, 1.14). Declines in Ra activity ratio (excess) with sediment depth can be used to estimate an average rate of burial of 4 cm/a for the Ra-bearing contaminant. Local shallow ground waters contaminated with NaCl from produced-water have low dissolved Ra (
Distributed implementation of an augmented state dynamic estimator

Load models are commonly approximated by fixed impedance type loads when formulating dynamic simulations. This is an acceptable approximation when using dynamic simulation for a specific initial operating condition and the study runs for a brief period typically to check system stability. When implementing an on-line dynamic estimator such assumptions may not be viable due to the load dynamics which are not typically known. Another difficulty is related to the sheer size of the problem when a large scale system is considered with several generators. This paper addresses these problems by extending the state vector to include network variables, thus eliminating the need to model loads and also by implementing a distributed yet synchronized solution algorithm that facilities simultaneous solutions by multiple areas. Previously studied Unscented Kalman Filter (UKF) is used and the proposed method is tested on the New-England 37-bus system.
Clinical significance of distal embolization after transluminal extraction atherectomy in diffusely diseased saphenous vein grafts

Standard balloon angioplasty of degenerated saphenous vein graft lesions may be complicated by distal embolization, particularly in the presence of intragraft thrombus. Transluminal extraction atherectomy may be useful in this setting because of its ability to remove particulate debris. This study was designed to identify the incidence and prognostic significance of distal embolization after transluminal extraction atherectomy in high-risk saphenous vein graft lesions. To address these issues the clinical course of 65 consecutive patients (86 high-risk saphenous vein graft lesions) was reviewed after extraction atherectomy. Distal embolization occurred in 11 (12.8%) of 86 high-risk lesions. The majority (63.6%) of these episodes occurred after adjunct balloon dilatation following uncomplicated use of the extraction atherectomy catheter. Correlates of distal embolization included patient age and the presence of intragraft thrombus. Major in-hospital complications developed more often in patients with distal embolization (46% vs 2% in those without distal embolization, p < 0.001), resulting in a reduced procedural success rate in this group (55% vs 91%, p = 0.01). We conclude that the risk of distal embolization after saphenous vein graft angioplasty, although potentially reduced, is not eliminated with transluminal extraction atherectomy, particularly in lesions with superimposed thrombus.
A Note on the Determinants of Recent Pupil Achievement

This analysis focuses on the average state scores in 2013 for reading and mathematics of fourth and eighth grade pupils taking the National Assessment of Educational Progress. Of the 19 possible determinants that are tested, two are most important: average pupil/teacher ratios in the state and the share of pupils coming from low income families who are eligible for free or low cost lunches. Most of the other variables focusing on pupil and school characteristics or on state policies such as expenditures on education, length of school year, or required attendance at kindergartens did not have a statistically significant impact.
A cautious view of putative precursors of serous carcinomas in the fallopian tubes of BRCA mutation carriers.

Abstract Objective To compare the frequency and distribution of candidate precursors of serous carcinoma in the fallopian tubes of BRCA mutation carriers to BRCA non-mutation carriers (controls) at risk-reducing bilateral salpingo-oophorectomy (RRSO). Methods 78 BRCA carriers (52 BRCA1, 26 BRCA2) and 23 controls underwent RRSO. Fallopian tubes were serially cross-sectioned, and adnexa were entirely submitted and examined by two gynecologic pathologists blinded to BRCA mutation status. The presence and location of serous tubal intraepithelial carcinoma (STIC), p53 overexpression (≥6 consecutively stained nuclei), Ki67 overexpression, atypia/low grade dysplasia and epithelial hyperplasia were compared between BRCA carriers and controls. Patient age was dichotomized: ≤50 and >50years. Results 9 (12%) BRCA carriers had occult carcinoma: 8 STIC and 1 stage IC tubal carcinoma with STIC. No occult carcinomas or STIC was seen in controls. STIC involved the distal tube in all cases and was multifocal in three cases. STIC was more common in women >50 (p=0.06). P53 overexpression was common in BRCA carriers (30%) and controls (43%) (p=0.5) and did not correlate with age. Only 5/9 (55%) of STIC exhibited p53 overexpression. 2 patients had Ki67 overexpression: both BRCA1 carriers with STIC. No difference in the frequency of atypia/low grade dysplasia or hyperplasia was observed between BRCA carriers and controls. Conclusions STIC is the dominant precursor of serous fallopian tube carcinoma in BRCA carriers. There is insufficient evidence to support p53 overexpression alone as a putative precursor. Atypia/low grade dysplasia and epithelial hyperplasia are not pre-neoplastic lesions of serous fallopian tube carcinoma.
Treatment of hypertension--a pragmatic approach.

Abstract Additional long-term studies of treated hypertensive patients are necessary before final conclusions can be reached. It would appear, however, from the controlled series of the Veterans Administration and others, and from a long-term study of private practice patients that: (1) blood pressure can be controlled in the vast majority of patients utilizing all of the presently available medications alone or in combination; (2) the occurrence of cerebral vascular hemorrhage, progressive renal failure, pulmonary edema, and the progression to hypertensive encephalopathy can be greatly reduced or eliminated by blood pressure control; and (3) it is possible that earlier treatment of the patient before he develops complications of coronary artery disease might significantly reduce the mortality rate from this complication. All of the studies to date have clearly demonstrated in different population groups and with differing initial criteria the simple fact that the usual complications and the progressive decrease in survival that have occurred in hypertensive patients can be reversed by adequate continuing antihypertensive drug therapy. Hypertension may indeed be a “reversible risk factor.”
Short-Term Fluctuations in U.S. Voting Behavior, 1896–1964

This paper develops several simple multivariate statistical models and applies them to explain fluctuations in the aggregate vote for the United States House of Representatives, over the period 1896-1964. The basic hypothesis underlying these models is that voters are rational in at least the limited sense that their decisions as to whether to vote for an incumbent administration depend on whether its performance has been “satisfactory” according to some simple standard. Because of data limitations, the analysis focuses on measures of economic performance, treating other aspects of an incumbent's performance, such as its handling of foreign affairs, as stochastic perturbations of the underlying relationship to be estimated. (Examination of residuals suggests this assumption is not unreasonable, at least during peacetime.) Possible effects of coattails from presidential races, of incumbency, and of secular trends in the underlying partisanship of the electorate are also taken into account. The models, estimated by maximum-likelihood methods, are found to be successful. Close to two-thirds of the variance in the vote series is accounted for, and the structural coefficients of the models are of the correct signs and of quite reasonable magnitudes. Economic growth, as measured by the changes in real per capita income, is the major economic variable; unemployment or inflation have little independent effect. Presidential coattails are also found to be of some importance.
Poor Relief in Ireland, 1851–1914. By Mel Cousins. (New York, NY: Peter Lang, 2011. Pp. xiii, 307. $68.95.)

To put a spin on the well‐worn American political maxim, the author argues in this book that poor‐relief policy in Ireland was essentially local. From 1851–1914, local poor‐law boards of guardians ...
Chemokine receptors in psoriasis.

Introduction: Psoriasis is a prevalent immune-mediated disease involving primarily the skin. Infiltrating leukocytes play key roles in driving the disease. Along with an array of adhesion proteins, leukocyte trafficking into tissue is controlled by chemoattractants, including chemokines, and their receptors. This review summarizes the data on roles for the chemokine system in psoriasis in order to highlight opportunities for inhibiting this system for therapeutic benefit. Areas covered: The review covers the roles of various leukocyte subsets in psoriasis, focusing on the chemokine receptors that are thought to be responsible for the trafficking of these cells into tissue. The review also discusses in some detail the significance of the IL-23/IL-17/IL-22 cytokine axis in disease. Expert opinion: Many of the new therapies developed for psoriasis are antibodies to neutralize cytokines that have pleiotropic functions in host defense. Inhibiting chemokine receptors can be accomplished using small molecules, a...
Operon prediction in cyanobacteria using comparative genomics

In this work, we performed a comprehensive analysis of the genome organization of eight publicly available cyanobacterial genomes and of the extensively studied Escherichia coli K12. Our comparison revealed striking similarities in organization of different microbial genomes. We examined the orientation of putative CDS, and distance distribution patterns between adjacent putative CDS in the whole genome as well as between genes within operons and across operon borders. Our results enabled us to calculate distance log-likeihoods for gene pairs to be part of the same operon and to apply this metric to predict operons in two newly sequenced cyanobacterial genomes, Synechococcus OS-A and OS-B'.