Transformations among large c conformal field theories

We show that there is a set of transformations that relates all of the 24 dimensional even self-dual (Niemeier) lattices, and also leads to non-lattice objects that however cannot be interpreted as a basis for the construction of holomorphic conformal field theory. In the second part of this paper, we extend our observations to higher dimensional conformal field theories build on extremal partition functions, where we generate c=24k theories with spectra decomposable into the irreducible representations of the Fischer-Griess Monster. We observe interesting periodicities in the coefficients of extremal partition functions and characters of the extremal vertex operator algebras.Comment: 14 pages, minor corrections, new references adde

Quantum Relativity of Subsystems

One of the most basic notions in physics is the partitioning of a system into subsystems, and the study of correlations among its parts. In this work, we explore these notions in the context of quantum reference frame (QRF) covariance, in which this partitioning is subject to a symmetry constraint. We demonstrate that different reference frame perspectives induce different sets of subsystem observable algebras, which leads to a gauge-invariant, frame-dependent notion of subsystems and entanglement. We further demonstrate that subalgebras which commute before imposing the symmetry constraint can translate into non-commuting algebras in a given QRF perspective after symmetry imposition. Such a QRF perspective does not inherit the distinction between subsystems in terms of the corresponding tensor factorizability of the kinematical Hilbert space and observable algebra. Since the condition for this to occur is contingent on the choice of QRF, the notion of subsystem locality is frame-dependent.Comment: 8+9 pages, 1 figur

TEST METHODS FOR GEAR LUBRICANTS

Vrsta baznog ulja, viskoznost ulja, vrsta i sadržaj aditiva imaju značajan utjecaj na tipična oštećenja zupčanika. Općenito nije moguće jednostavno brojčano odrediti utjecaj maziva na sposobnost podnošenja opterećenja temeljem poznavanja fizikalno-kemijskih podataka o ulju. Stoga su razvijeni mnogobrojni ispitni postupci za procjenu mehaničko-tehnoloških svojstava maziva. Jednostavna i jeftina ispitivanja na probnim stolovima često pokazuju lošu korelaciju s praksom. Iz iskustva i sustavnog istraživanja moguće je pokazati da ispitivanje maziva za zupčanike može biti izvedeno na odgovarajući način samo u uređajima za ispitivanje zupčanika koja koriste specificiranu geometriju zupčanika [1]. Dugogodišnjim radom razvijen je normirani FZG probni stol sa čelnim zupčanicima s vanjskim ozubljenjem te unaprijeđen za različite vrste simulacija oštećenja zupčanika. Uobičajeni FZG uljni test A/8,3/90 široko je korišten za ocjenu svojstava ulja za industrijske zupčanike s obzirom na zaribavanje. Ulja za zupčanike vozila razine GL4 mogu se ispitivati u Step testu A10/16.6R/90, a ulja za osovine razine GL5 u Shock testu S-A10/16.6R/90. Za male brzine se može primijeniti test trošenja C/0.05/90:120. Utjecaj maziva na mikropiting ili mikrotočkastu koroziju zupčanika moguće je procijeniti pomoću kratkog testa za dodatnu provjeru GFKT-C/8,3/90. Postoje različita ispitivanja pitinga ili točkaste korozije poput testa s jednostrukim stupnjem opterećenja PT-C/9:10/90 ili testa primjene PTX-C/SNC/90. Cilj rada je opisati utjecaj maziva na različite načine oštećenja u zupčanicima, kako kvantificirati taj utjecaj u ispitnim postupcima i kako rezultate ispitivanja predstaviti kao "značajne veličine" za mazivo u postupcima ocjenjivanja sposobnosti štetnog opterećenja.Base oil type, oil viscosity, additive type and content have a strong influence on typical gear failures. In general it is not possible to quantify the lubricant influence on load carrying capacity simply from the knowledge of physical or chemical oil data. Therefore many test methods were developed for the evaluation of mechanical-technological lubricant properties. Simple low-cost bench test methods often show poor correlation with practice. From experience and systematic investigations it can be shown that testing of gear lubricants can adequately be performed only in gear test rigs using specified test gear geometry [1]. In continuous work over many years the standard FZG back-to-back gear test rig was developed and improved for different types of gear failure simulation. The standard FZG oil test A/8,3/90 is widely used for the evaluation of the scuffing properties of industrial gear oils. Automotive gear oils of GL4 level can be tested in the step test A10/16.6R/90, axle oils of GL5 level in the shock test S-A10/16.6R/90. For the slow speed regime the wear test C/0.05/90:120/12 can be applied. The influence of lubricants on the micropitting performance of gears can be evaluated in a screening short test GFKT-C/8,3/90 or in the full micropitting test GF-C/8,3/90. Different pitting tests are available as single stage test PT-C/9:10/90 or application test PTX-C/SNC/90. The aim of the paper is to describe the influence of the lubricant on the different failure modes in gears, how to quantify this influence in adequate test methods and how to introduce the results of such tests as “strength values” for the lubricant into load carrying capacity rating methods

TEST METHODS FOR GEAR LUBRICANTS

Vrsta baznog ulja, viskoznost ulja, vrsta i sadržaj aditiva imaju značajan utjecaj na tipična oštećenja zupčanika. Općenito nije moguće jednostavno brojčano odrediti utjecaj maziva na sposobnost podnošenja opterećenja temeljem poznavanja fizikalno-kemijskih podataka o ulju. Stoga su razvijeni mnogobrojni ispitni postupci za procjenu mehaničko-tehnoloških svojstava maziva. Jednostavna i jeftina ispitivanja na probnim stolovima često pokazuju lošu korelaciju s praksom. Iz iskustva i sustavnog istraživanja moguće je pokazati da ispitivanje maziva za zupčanike može biti izvedeno na odgovarajući način samo u uređajima za ispitivanje zupčanika koja koriste specificiranu geometriju zupčanika [1]. Dugogodišnjim radom razvijen je normirani FZG probni stol sa čelnim zupčanicima s vanjskim ozubljenjem te unaprijeđen za različite vrste simulacija oštećenja zupčanika. Uobičajeni FZG uljni test A/8,3/90 široko je korišten za ocjenu svojstava ulja za industrijske zupčanike s obzirom na zaribavanje. Ulja za zupčanike vozila razine GL4 mogu se ispitivati u Step testu A10/16.6R/90, a ulja za osovine razine GL5 u Shock testu S-A10/16.6R/90. Za male brzine se može primijeniti test trošenja C/0.05/90:120. Utjecaj maziva na mikropiting ili mikrotočkastu koroziju zupčanika moguće je procijeniti pomoću kratkog testa za dodatnu provjeru GFKT-C/8,3/90. Postoje različita ispitivanja pitinga ili točkaste korozije poput testa s jednostrukim stupnjem opterećenja PT-C/9:10/90 ili testa primjene PTX-C/SNC/90. Cilj rada je opisati utjecaj maziva na različite načine oštećenja u zupčanicima, kako kvantificirati taj utjecaj u ispitnim postupcima i kako rezultate ispitivanja predstaviti kao "značajne veličine" za mazivo u postupcima ocjenjivanja sposobnosti štetnog opterećenja.Base oil type, oil viscosity, additive type and content have a strong influence on typical gear failures. In general it is not possible to quantify the lubricant influence on load carrying capacity simply from the knowledge of physical or chemical oil data. Therefore many test methods were developed for the evaluation of mechanical-technological lubricant properties. Simple low-cost bench test methods often show poor correlation with practice. From experience and systematic investigations it can be shown that testing of gear lubricants can adequately be performed only in gear test rigs using specified test gear geometry [1]. In continuous work over many years the standard FZG back-to-back gear test rig was developed and improved for different types of gear failure simulation. The standard FZG oil test A/8,3/90 is widely used for the evaluation of the scuffing properties of industrial gear oils. Automotive gear oils of GL4 level can be tested in the step test A10/16.6R/90, axle oils of GL5 level in the shock test S-A10/16.6R/90. For the slow speed regime the wear test C/0.05/90:120/12 can be applied. The influence of lubricants on the micropitting performance of gears can be evaluated in a screening short test GFKT-C/8,3/90 or in the full micropitting test GF-C/8,3/90. Different pitting tests are available as single stage test PT-C/9:10/90 or application test PTX-C/SNC/90. The aim of the paper is to describe the influence of the lubricant on the different failure modes in gears, how to quantify this influence in adequate test methods and how to introduce the results of such tests as “strength values” for the lubricant into load carrying capacity rating methods

Identification of Microbial and Proteomic Biomarkers in Early Childhood Caries

The purpose of this study was to provide a univariate and multivariate analysis of genomic microbial data and salivary mass-spectrometry proteomic profiles for dental caries outcomes. In order to determine potential useful biomarkers for dental caries, a multivariate classification analysis was employed to build predictive models capable of classifying microbial and salivary sample profiles with generalization performance. We used high-throughput methodologies including multiplexed microbial arrays and SELDI-TOF-MS profiling to characterize the oral flora and salivary proteome in 204 children aged 1–8 years (n = 118 caries-free, n = 86 caries-active). The population received little dental care and was deemed at high risk for childhood caries. Findings of the study indicate that models incorporating both microbial and proteomic data are superior to models of only microbial or salivary data alone. Comparison of results for the combined and independent data suggests that the combination of proteomic and microbial sources is beneficial for the classification accuracy and that combined data lead to improved predictive models for caries-active and caries-free patients. The best predictive model had a 6% test error, >92% sensitivity, and >95% specificity. These findings suggest that further characterization of the oral microflora and the salivary proteome associated with health and caries may provide clinically useful biomarkers to better predict future caries experience

Tracers as Essential Tools for the Investigation of Physical and Chemical Processes in Groundwater Systems

In complex environmental systems, tracers are indispensable tools for the investigation of various physical, chemical, and biological processes. From the large variety of tracers employed by EAWAG in the aquatic environment, we present some examples relevant to groundwater research. Some tracers (e.g., 222Rn, 3H/3He, chlorofluorocarbons) allow the time since groundwater infiltration to be determined; this information can be used to quantify process rates such as flow velocities, recharge and reaction rates. Other tracers (e.g., conductivity, isotopes of oxygen or boron) can be used to quantify mixing ratios between waters of different origin, for instance, to study the admixture of leachate from a landfill to an aquifer. In contrast to these inert tracers, chemically reactive tracers (e.g., nitroaromatic compounds) can be used to study subsurface biogeochemical transformation processes, e.g. the reduction of contaminants under anaerobic conditions. The successful use of tracers in the study of environmental systems requires highly developed analytical facilities for a broad palette of tracer measurements and a careful choice of appropriate tracers for each specific problem

Computational strategies for dissecting the high-dimensional complexity of adaptive immune repertoires

The adaptive immune system recognizes antigens via an immense array of antigen-binding antibodies and T-cell receptors, the immune repertoire. The interrogation of immune repertoires is of high relevance for understanding the adaptive immune response in disease and infection (e.g., autoimmunity, cancer, HIV). Adaptive immune receptor repertoire sequencing (AIRR-seq) has driven the quantitative and molecular-level profiling of immune repertoires thereby revealing the high-dimensional complexity of the immune receptor sequence landscape. Several methods for the computational and statistical analysis of large-scale AIRR-seq data have been developed to resolve immune repertoire complexity in order to understand the dynamics of adaptive immunity. Here, we review the current research on (i) diversity, (ii) clustering and network, (iii) phylogenetic and (iv) machine learning methods applied to dissect, quantify and compare the architecture, evolution, and specificity of immune repertoires. We summarize outstanding questions in computational immunology and propose future directions for systems immunology towards coupling AIRR-seq with the computational discovery of immunotherapeutics, vaccines, and immunodiagnostics.Comment: 27 pages, 2 figure