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We initiate the study of a new class of polynomials which we call quasi-subfield polynomials. First, we show that this class of polynomials could lead to more efficient attacks for the elliptic curve discrete logarithm problem via the index calculus approach. Specifically, we use these polynomials to construct factor bases for the index calculus approach and we provide explicit complexity bounds. Next, we investigate the existence of quasi-subfield polynomials.

Accumulating evidence argues for a more widespread use of therapeutic drug monitoring (TDM) to support individualized medicine, especially for therapies where toxicity and efficacy are critical issues, such as in oncology. However, development of TDM assays struggles to keep pace with the rapid introduction of new drugs. Therefore, novel approaches for faster assay development are needed that also allow effortless inclusion of newly approved drugs as well as customization to smaller subsets if scientific or clinical situations require. We applied and evaluated two machine-learning approaches i.e., a regression-based approach and an artificial neural network (ANN) to retention time (RT) prediction for efficient development of a liquid chromatography mass spectrometry (LC-MS) method quantifying 73 oral antitumor drugs (OADs) and five active metabolites. Individual steps included training, evaluation, comparison, and application of the superior approach to RT prediction, followed by stipulation of the optimal gradient. Both approaches showed excellent results for RT prediction (mean difference ± standard deviation: 2.08 % ± 9.44 % ANN; 1.78 % ± 1.93 % regression-based approach). Using the regression-based approach, the optimum gradient (4.91 % MeOH/min) was predicted with a total run time of 17.92 min. The associated method was fully validated following FDA and EMA guidelines. Exemplary modification and application of the regression-based approach to a subset of 14 uro-oncological agents resulted in a considerably shortened run time of 9.29 min. Using a regression-based approach, a multi drug LC-MS assay for RT prediction was efficiently developed, which can be easily expanded to newly approved OADs and customized to smaller subsets if required. [ABSTRACT FROM AUTHOR]

This article reports on the use of a digital application (EVALOE-SSD) for the professional development of teachers to improve the linguistic competence of their students. We conducted a multiple case study that involved five teachers and their students from different schools. Over a period of three months, the teachers used the digital application to assess their classes, make decisions and introduce changes in their teaching practices. The results show that the change process includes stages of progress and stages of regression, but in general the trend was to a progressive increase in scores. Therefore, the use of the digital application improved the competences of teachers and students, regardless of the type of school or students' age. This is shown in the cases of two teachers, which are analysed in greater depth. We believe that our findings are important as they document how self-reflection, stimulated by aids such as video recordings, reflective questions and pictures, facilitates a change in teaching practices. At the end of the programme, all the teachers stated that the experience of using the digital tool had clearly been enriching, and they had learnt and improved teaching practice linked to communicative competence. [ABSTRACT FROM AUTHOR]

Value functions are used in sports to determine the optimal action players should employ. However, most literature implicitly assumes that players can perform the prescribed action with known and fixed probability of success. The effect of varying this probability or, equivalently, "execution error" in implementing an action (e.g., hitting a tennis ball to a specific location on the court) on the design of optimal strategies, has received limited attention. In this paper, we develop a novel modeling framework based on Markov reward processes and Markov decision processes to investigate how execution error impacts a player's value function and strategy in tennis. We power our models with hundreds of millions of simulated tennis shots with 3D ball and 2D player tracking data. We find that optimal shot selection strategies in tennis become more conservative as execution error grows, and that having perfect execution with the empirical shot selection strategy is roughly equivalent to choosing one or two optimal shots with average execution error. We find that execution error on backhand shots is more costly than on forehand shots, and that optimal shot selection on a serve return is more valuable than on any other shot, over all values of execution error. [ABSTRACT FROM AUTHOR]

Copyright of Automatisierungstechnik is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dieser Beitrag setzt sich kritisch mit in zahlreichen Bereichen zunehmend umgesetzten Prozessen und den dahinterliegenden Begriffen der 'gamification' / 'Gamifizierung' auseinander, indem Unterschiede zwischen dem deutschsprachigen Begriff 'Spiel' und dem englischsprachigen Begriff 'game' produktiv gemacht werden. Im ersten Teil wird nach einer Diskussion einschlägiger theoretischer Ansätze eine heuristische Systematik in Anlehnung an Roger Caillois' Unterscheidung von paidia und ludus entworfen, durch die eine Schärfung des Gamifizierungs-Begriffs anhand einer Unterscheidung von Spiel und Game und den jeweiligen Derivaten (spielen, gamen, spielerisch, gamerisch etc.) ermöglicht wird. Die daraus generierte Arbeitsbestimmung von 'Gamifizierung' wird geprüft anhand eines im zweiten Teil gegebenen andragogischen Fallbeispiels, i.e. die aus autoethnographischer Perspektive beschriebene Teilnahme an einem zehntägigen Vipannasa-Meditationskurs in der Tradition von S.N. Goenka. Im dritten Teil werden der theoretische und ethnographische Teil zusammengeführt in Form einer Diskussion der in der goenkaschen Tradition erfolgten Gamifizierung buddhistischer Praktiken. [ABSTRACT FROM AUTHOR]

Enhancing the circular dichroism signals of chiral plasmonic nanostructures is vital for realizing miniaturized functional chiroptical devices, such as ultrathin wave plates and high-performance chiral biosensors. Rationally assembling individual plasmonic metamolecules into coupled nanoclusters or periodic arrays provides an extra degree of freedom to effectively manipulate and leverage the intrinsic circular dichroism of the constituent structures. Here, we show that sophisticated manipulation over the geometric parameters of a plasmonic stereo-metamolecule array enables selective excitation of its surface lattice resonance mode either by left- or right-handed circularly polarized incidence through diffraction coupling, which can significantly amplify the differential absorption and hence the intrinsic circular dichroism. In particular, since the diffraction coupling requires no index-matching condition and its handedness can be switched by manipulating the refractive index of either the superstrate or the substrate, it is therefore possible to achieve dynamic tuning and active control of the intrinsic circular dichroism response without the need of modifying structure parameters. Our proposed system provides a versatile platform for ultrasensitive chiral plasmonics biosensing and light field manipulation. [ABSTRACT FROM AUTHOR]

In 2017, we decided to start the annual series of MathCrypt Workshops in order to encourage more mathematicians and computational number theorists to propose and work on hard problems in cryptography. In fact, a Program Officer from NSF spoke at the first MathCrypt workshop in August and encouraged participants to apply to the NSF SaTC program for potential support for their research. The founders of MathCrypt, Jung Hee Cheon and Kristin Lauter, acted as Program Chairs, and were joined by Jintai Ding to form the Organizing Committee. [Extracted from the article]

We describe a framework for constructing an efficient non-interactive key exchange (NIKE) protocol for n parties for any n ≥ 2. Our approach is based on the problem of computing isogenies between isogenous elliptic curves, which is believed to be difficult. We do not obtain a working protocol because of a missing step that is currently an open mathematical problem. What we need to complete our protocol is an efficient algorithm that takes as input an abelian variety presented as a product of isogenous elliptic curves, and outputs an isomorphism invariant of the abelian variety. Our framework builds a cryptographic invariant map, which is a new primitive closely related to a cryptographic multilinear map, but whose range does not necessarily have a group structure. Nevertheless, we show that a cryptographic invariant map can be used to build several cryptographic primitives, including NIKE, that were previously constructed from multilinear maps and indistinguishability obfuscation. [ABSTRACT FROM AUTHOR]

This study analyzes how agri-food Entrepreneurial Assistance Programs (EAPs) create value for entrepreneurs. Using the MSU Product Center as a unit of analysis, the effect of agri-food EAP assistance on firms' venture evaluation, perceived legitimacy, and performance is examined. Results indicate that agri-food EAP assistance prevents untenable business ideas from launching, improves the survival of launched ventures and develops entrepreneurs' perceived legitimacy with trading partners. Further, results imply that targeted EAPs are a viable policy approach for promoting entrepreneurial activity in the agri-food industry, and that they can be particularly well suited to assisting nascent entrepreneurs. [ABSTRACT FROM AUTHOR]

C28H78Si10, monoclinic, Pn (no. 7), a = 21.413(4) Å, b = 9.8568(17) Å, c = 22.074(4) Å, β = 93.426(4)°, V = 4650.6(14) Å3, Z = 4, Rgt(F) = 0.0613, wRref(F2) = 0.1750, T = 296(2) K. [ABSTRACT FROM AUTHOR]

We improve on the first fall degree bound of polynomial systems that arise from a Weil descent along Semaev's summation polynomials relevant to the solution of the Elliptic Curve Discrete Logarithm Problem via Gröbner basis algorithms. [ABSTRACT FROM AUTHOR]

The employability of an aging population in a world of continuous and biased technical change is top of the political agenda. Due to endogenous human capital depreciation the effective retirement age is often below statutory retirement age resulting in permanent non‐employability of older workers. We analyze this phenomenon in a putty‐putty human capital vintage model and focus on education and the speed of human capital depreciation. Introducing a two‐stage education system with initial schooling and lifelong learning, not even lifelong learning turns out to be capable of aligning economic and statutory retirement. However, well‐designed education programs will keep more workers in highly productive activities at the end of their working life, and hence will substitute for simple social transfers, or for an early switch towards very low paid jobs. [ABSTRACT FROM AUTHOR]

We propose a variational model to simultaneous reconstruction and segmentation in emission tomography. As in the original Mumford-Shah model [] we use the contour length as penalty term to preserve edge information whereas a different data fidelity term is used to measure the information discrimination between the computed tomography data of the reconstructed object and the observed (or simulated) data. As data fidelity term we use the Kullback-Leibler divergence which originates from the Poisson distribution present in emission tomography. In this paper we focus on piecewise constant reconstructions which is a reasonable assumption in medical imaging. The segmenting contour as well as the corresponding reconstructions are found as minimizers of a Mumford-Shah-type functional over the space of piecewise constant functions. The numerical scheme is implemented by evolving the level-set surface according to the shape derivative of the functional. The method is validated for simulated data with different levels of noise. [ABSTRACT FROM AUTHOR]

Das Diskriminierungsverbot ist zwar ein wichtiger Grundsatz in der Europäischen Union (EU), über seine Auswirkungen innerhalb der Mitgliedsstaaten ist bisher allerdings wenig bekannt. Wir gehen davon aus, dass das Diskriminierungsverbot das Ausmaß von Lohndiskriminierung gegen EU-Ausländer auf den nationalen Arbeitsmärkten in der EU verringert. Diese Vermutung wird mit administrativen Prozessdaten überprüft, indem die Veränderungen von Lohnunterschieden zwischen vollzeitbeschäftigten deutschen und ausländischen Männern auf dem westdeutschen Arbeitsmarkt mit Juhn-Murphy-Pierce-Zerlegungen analysiert werden. Die Ergebnisse stützen die Hypothese: Während die Lohndiskriminierung für die meisten untersuchten Gruppen von EU-Ausländern nach dem Beitritt ihrer Herkunftsländer zurückgegangen ist, lässt sich für die meisten Ausländergruppen aus Drittstaaten gestiegene oder konstante Lohndiskriminierung beobachten. Die europäischen Nichtdiskriminierungsregeln und die mit ihnen verbundenen Übertragungsmechanismen wirken demnach in die intendierte Richtung. The prohibition of all types of discrimination is one of the tenets of the European Union (EU), but we know little about their effects in EU member states. Our hypothesis is that such regulations prevent within-job wage discrimination against EU foreigners in national labor markets. We test this assumption by decomposing changes in wage differences between German male employees and foreigners in the West German labor market by applying Juhn-Murphy-Pierce decompositions on administrative data. The findings generally support our hypothesis. While wage discrimination decreased for most groups of EU foreigners and for most rounds of EU enlargement, it rose for most groups of third-country nationals. We conclude that EU anti-discrimination provisions and case law ensuring free movement mitigate wage discrimination against EU foreigners in the German labor market. [ABSTRACT FROM AUTHOR]

Balanced budget requirements should achieve fiscal sustainability, avoid a burden on future generations and allow for flexible reactions to cyclical fluctuations in the economy. There are many types of balanced budget requirements and debt limitations with different stringency. These budget restraints have a significant effect when they are applicable. The overall effect on public debt is small since there are many ways to circumvent or evade the restraints. Therefore budget restraints have substantial negative side effects. Public debt is transferred into less controllable budget areas, the structure of governments becomes fragmented and the balance of power is shifted away from the democratically accountable legislature. [ABSTRACT FROM AUTHOR]

Phyllosilicates are among the most important stable minerals within the Earth's crust. Their use as geo-thermometer bears great potential for application to the thermal history of rocks within the stability range of layered silicates and was tested here. A high-resolution analytical technique combining focused ion beam (FIB) milling and analytical electron microscopy (AEM) analysis has been applied to a series of sandstone core samples from the Gulf Coast (Texas, U.S.A.). The nanoscale compositional variations of K-deficient mica and chlorite flakes show that rim compositions are the most likely to approach equilibrium compositions, whereas core compositions may be relict, especially for illite-like phases. These rim analyses were used to test existing empirical or thermodynamically formulated thermo(baro)meters against maximum temperatures, which are perfectly constrained for the selected samples as they were measured in situ during drilling (100-230 °C and 300-1200 bars). The results show that most of the empirical models overestimate the temperature, while thermodynamic models yields reasonable estimates for diagenetic to anchizonal conditions, especially if the Fe3+ content is taken into account. This study clearly shows that phyllosilicates thermometry is reliable when combined with an analytical technique giving access to the fine-scale compositional variations that may represent local equilibration, whereas using micrometric compositional analysis precludes trustworthy application of such thermometers. [ABSTRACT FROM AUTHOR]

Copyright of Turkish Journal of Biochemistry / Turk Biyokimya Dergisi is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives: Fetal neutrophilia is present in two-thirds of cases with the fetal inflammatory response syndrome (FIRS). The mechanisms responsible for this finding have not been elucidated. Granulocyte colony-stimulating factor (G-CSF) is the primary physiologic regulator of neutrophil production and plays a key role in the rapid generation and release of neutrophils in stressful conditions (i.e., infection). The objective of this study was to determine: 1) whether FIRS was associated with changes in fetal plasma G-CSF concentrations; and 2) if fetal plasma G-CSF concentrations correlated with fetal neutrophil counts, chorioamnionitis, neonatal morbidity/mortality and cordocentesis-to-delivery interval. Study design: Percutaneous umbilical cord blood sampling was performed in a population of patients with preterm labor (n=107). A fetal plasma interleukin-6 (IL-6) concentration >11 pg/mL was used to define FIRS. Cord blood G-CSF was measured by a sensitive and specific immunoassay. An absolute neutrophil count was determined and corrected for gestational age. Receiver operating characteristic (ROC) curve, survival analysis and Cox proportional hazard model were employed. Results: 1) G-CSF was detected in all fetal blood samples; 2) fetuses with FIRS had a higher median fetal plasma G-CSF concentration than those without FIRS (P<0.001); 3) a fetal plasma G-CSF concentration ≥134 pg/mL (derived from an ROC curve) was associated with a shorter cordocentesis-to-delivery interval, a higher frequency of chorioamnionitis (clinical and histological), intra-amniotic infection, and composite neonatal morbidity/mortality than a fetal plasma concentration below this cut-off; and 4) a fetal plasma G-CSF concentration ≥134 pg/mL was associated with a shorter cordocentesis-to-delivery interval (hazard ratio 3.2; 95% confidence interval 1.8-5.8) after adjusting for confounders. Conclusions: 1) G-CSF concentrations are higher in the peripheral blood of fetuses with FIRS than in fetuses without FIRS; and 2) a subset of fetuses with FIRS with elevated fetal plasma G-CSF concentrations are associated with neutrophilia, a shorter procedure-to-delivery interval, chorio-amnionitis and increased perinatal morbidity and mortality. [ABSTRACT FROM AUTHOR]

Transmembrane protein 192 (TMEM192) has been previously identified in proteomic analyses of lysosomal membranes. TMEM192 does not exhibit any significant homology to known protein families and possesses four potential transmembrane segments. To approach the molecular role of TMEM192, a detailed biochemical characterisation of this protein was performed. Expression constructs of fusion proteins containing TMEM192 and appended epitope tags were constructed. In HeLa cells these proteins were detected in membranes of lysosomes/late endosomes. To examine endogenous TMEM192, a TMEM192-specific antibody was generated and validated. With this antibody colocalisation of endogenous TMEM192 with lysosomal and late endosomal markers was demonstrated. Using Percoll density gradient centrifugation and immunoblotting, co-sedimentation of major portions of both TMEM192 and the lysosomal proteins LAMP-2 and cathepsin D into high-density fractions was observed. Interestingly, in contrast to many other lysosomal proteins no N-glycosylation of TMEM192 could be detected. Western blotting of reduced and non-reduced samples and co-immunoprecipitation experiments indicated TMEM192 to be a homodimer with one or more interchain disulphide bridges. TMEM192 was found to be strongly expressed in human kidney, liver, lung and pancreas tissue. The widespread tissue distribution could suggest an important role of TMEM192 for lysosomal function. [ABSTRACT FROM AUTHOR]

Gallstone disease is one of the most prevalent gastrointestinal disorders. In addition, the costs associated with the diagnosis and treatment of gallstone disease have been rapidly increasing. The etiology and pathogenesis of gallstone disease remains incompletely understood. Gallstone formation may result from a complex interaction of genetic and environmental factors. This article reviews the prevalence and risk factors associated with gallstone disease. Understanding the pathogenesis of gallstone disease could lead to the development of better therapeutic and preventive strategies for dealing with this disease. Clin Chem Lab Med 2009;47:795–807. [ABSTRACT FROM AUTHOR]

Recently available evidence emphasizes the role of cognitive skills in determining not only individual earnings but also national growth rates. While prior studies concentrated on just school attainment as a measure of human capital, the availability of more refined quality measures using student achievement assessments demonstrates the inadequacies of these pure quantity measures of schooling. Improving cognitive skills, such as those measured by PISA, has, however, proved difficult. The only viable approach appears to be improving the incentives for higher performance. But particularly the reactions to demand-side incentives indicate a requirement to focus incentives carefully on achievement. [ABSTRACT FROM AUTHOR]

Background: Gallstone analysis is important in determining the possible etiology of stone formation and the pathophysiology of cholelithiasis. Physical analysis using Fourier transform infrared spectroscopy (FT-IR), compared to chemical analysis, requires minimal sample volume, shows uniform sensitivity and specificity for all components and provides quantitative results with greater reproducibility. We studied the characteristics and distribution of gallstones using FT-IR in addition to the risk factors for gallstone formation in Korean patients. A better understanding of the mechanism underlying stone formation may help prevent gallstone development. Methods: Physical analysis of gallstones in 490 patients who underwent cholecystectomy was carried out using the FT-IR system 2000 (Perkin-Elmer Co.) and Spectrum™ software (Perkin-Elmer Co.). Visual inspection of the size, color, consistency and surface of the stones was compared with the physical characteristics. Clinical, demographic and laboratory findings were evaluated and compared with the gallstone components. Results: The FT-IR evaluation showed that most gallstones were composed of a single component (84.1%); cholesterol was the most commonly observed element among the major components (50%, 245/490). Morphological classification according to color, consistency and surface was different from the FT-IR composition analysis. There were significant differences in the components based on age, obesity, education level and the presence of diabetes mellitus. Conclusions: The results of this study show that physical analysis of gallstones with FT-IR provides important information on stone composition, distribution and risk factors. These study results will help improve our understanding of the pathophysiology of gallstone disease in the Korean population, where there is a high frequency of hepatobiliary disorders. Clin Chem Lab Med 2008;46:376–81. [ABSTRACT FROM AUTHOR]

The hemoglobin (Hb) substitution His→Gln at position α89, very common in avian Hbs, is considered to be responsible for the weak Bohr effect of avian Hbs. Phoenicopterus ruber ruber is one of the few avian Hbs that possesses His at α89, but it has not been functionally characterized yet. In the present study the Hb system of the greater flamingo ( P. ruber roseus), a bird that lives in Mediterranean areas, has been investigated to obtain further insight into the role played by the α89 residue in determining the strong reduction of the Bohr effect. Functional analysis of the two purified Hb components (HbA and HbD) of P. ruber roseus showed that both are characterized by high oxygen affinity in the absence of organic phosphates, a strong modulating effect of inositol hexaphosphate, and a reduced Bohr effect. Indeed, in spite of the close phylogenetic relationship between the two flamingo species, structural analysis based on tandem mass spectrometry of the αA chain of P. ruber roseus Hb showed that a Gln residue is present at position α89. [ABSTRACT FROM AUTHOR]

Conversion of the cellular isoform of the prion protein (PrPC) into the disease-associated isoform (PrPSc) plays a key role in the development of prion diseases. Within its cellular pathway, PrPC undergoes several posttranslational modifications, i.e., the attachment of two N-linked glycans and a glycosyl phosphatidyl inositol (GPI) anchor, by which it is linked to the plasma membrane on the exterior cell surface. To study the interaction of PrPC with model membranes, we purified posttranslationally modified PrPC from transgenic Chinese hamster ovary (CHO) cells. The mono-, di- and oligomeric states of PrPC free in solution were analyzed by analytical ultracentrifugation. The interaction of PrPC with model membranes was studied using both lipid vesicles in solution and lipid bilayers bound to a chip surface. The equilibrium and mechanism of PrPC association with the model membranes were analyzed by surface plasmon resonance. Depending on the degree of saturation of binding sites, the concentration of PrPC released from the membrane into aqueous solution was estimated at between 10-9 and 10-7 M. This corresponds to a free energy of the insertion reaction of -48 kJ/mol. Consequences for the conversion of PrPC to PrPSc are discussed. [ABSTRACT FROM AUTHOR]

Recent national concerns about student performance on PISA tests and similar assessments appear warranted because of the direct relationship between student cognitive skills and both individual earnings and national growth. The evidence on the impacts of school quality indicates very large economic effects. Available research shows, however, that improving school quality is difficult and not closely related to spending levels. One approach supported by research is improving teacher quality, which can yield sizable gains in student performance. Instituting appropriate policies to alter the teacher force will necessarily take significant time. [ABSTRACT FROM AUTHOR]

Using data from the 1983 and 1989 Federal Reserve Board Surveys of Consumer Finances, we quantify three findings about entrepreneurial saving decisions and their role in household wealth accumulation. First, entrepreneurial households own a substantial share of household wealth and income, and this share increases throughout the wealth distribution and the income distribution. Second, the portfolios of entrepreneurial households, even wealthy ones, are very undiversified, with the bulk of assets held within active businesses. Third, wealth-income ratios and saving rates are higher for entrepreneurial households even after controlling for age and other demographic variables. Taken together, these findings suggest that studies of household saving decisions in general and of the savings decisions of wealthy or high-income households in particular have paid insufficient attention to the role of entrepreneurial decisions and their role in wealth accumulation. [ABSTRACT FROM AUTHOR]