Splitting full matrix algebras over algebraic number fields

Let K be an algebraic number field of degree d and discriminant D over Q. Let A be an associative algebra over K given by structure constants such that A is isomorphic to the algebra M_n(K) of n by n matrices over K for some positive integer n. Suppose that d, n and D are bounded. Then an isomorphism of A with M_n(K) can be constructed by a polynomial time ff-algorithm. (An ff-algorithm is a deterministic procedure which is allowed to call oracles for factoring integers and factoring univariate polynomials over finite fields.) As a consequence, we obtain a polynomial time ff-algorithm to compute isomorphisms of central simple algebras of bounded degree over K.Comment: 15 pages; Theorem 2 and Lemma 8 correcte

Avalanches in the Weakly Driven Frenkel-Kontorova Model

A damped chain of particles with harmonic nearest-neighbor interactions in a spatially periodic, piecewise harmonic potential (Frenkel-Kontorova model) is studied numerically. One end of the chain is pulled slowly which acts as a weak driving mechanism. The numerical study was performed in the limit of infinitely weak driving. The model exhibits avalanches starting at the pulled end of the chain. The dynamics of the avalanches and their size and strength distributions are studied in detail. The behavior depends on the value of the damping constant. For moderate values a erratic sequence of avalanches of all sizes occurs. The avalanche distributions are power-laws which is a key feature of self-organized criticality (SOC). It will be shown that the system selects a state where perturbations are just able to propagate through the whole system. For strong damping a regular behavior occurs where a sequence of states reappears periodically but shifted by an integer multiple of the period of the external potential. There is a broad transition regime between regular and irregular behavior, which is characterized by multistability between regular and irregular behavior. The avalanches are build up by sound waves and shock waves. Shock waves can turn their direction of propagation, or they can split into two pulses propagating in opposite directions leading to transient spatio-temporal chaos. PACS numbers: 05.70.Ln,05.50.+q,46.10.+zComment: 33 pages (RevTex), 15 Figures (available on request), appears in Phys. Rev.

Recent advances in pediatric anesthesia

Writing about advances in a field of medicine normally includes some pride about progress which one was witness to or even a participant in. The younger one is, the more enthusiastically every advance is lauded and welcomed. This is human nature and nothing to be complained about. However, when anesthesiologists, having worked and struggled in the field of pediatric anesthesia for about 40 years, look back to past advances, a more realistic, even painful picture comes to mind. There was a price which a considerable number of patients had to pay for progress, ruined health or even death. This experience of decades of practice is rarely presented in the literature but should not be forgotten when we proudly remember advances in pediatric anesthesia

European traditional tomatoes galore: a result of farmers' selection of a few diversity-rich loci

[EN] The high phenotypic diversity observed among European traditional tomato varieties was created by traditional farmer-driven selection by inadvertently combining a very few polymorphic loci subjected to balancing selection. A comprehensive collection of 1254 tomato accessions, corresponding to European traditional and modern varieties, early domesticated varieties, and wild relatives, was analyzed by genotyping by sequencing. A continuous genetic gradient between the traditional and modern varieties was observed. European traditional tomatoes displayed very low genetic diversity, with only 298 polymorphic loci (95% threshold) out of 64 943 total variants. European traditional tomatoes could be classified into several genetic groups. Two main clusters consisting of Spanish and Italian accessions showed higher genetic diversity than the remaining varieties, suggesting that these regions might be independent secondary centers of diversity with a different history. Other varieties seem to be the result of a more recent complex pattern of migrations and hybridizations among the European regions. Several polymorphic loci were associated in a genome-wide association study with fruit morphological traits in the European traditional collection. The corresponding alleles were found to contribute to the distinctive phenotypic characteristic of the genetic varietal groups. The few highly polymorphic loci associated with morphological traits in an otherwise a low-diversity population suggests a history of balancing selection, in which tomato farmers likely maintained the morphological variation by inadvertently applying a high selective pressure within different varietal types.This work was supported by the European Commission H2020 research and innovation program through TRADITOM grant agreement no. 634561, G2P-SOL, grant agreement no. 677379, and HARNESSTOM grant agreement no. 101000716. MP is grateful to the Spanish Ministerio de Ciencia e Innovacion for a postdoctoral grant (IJC2019-039091-I/AEI/10.13039/501100011033).Blanca Postigo, JM.; Pons Puig, C.; Montero-Pau, J.; Sánchez-Matarredona, D.; Ziarsolo, P.; Fontanet, L.; Fisher, J.... (2022). European traditional tomatoes galore: a result of farmers' selection of a few diversity-rich loci. Journal of Experimental Botany. 73(11):3431-3445. https://doi.org/10.1093/jxb/erac07234313445731

Atlas of phenotypic, genotypic and geographical diversity present in the European traditional tomato

[EN] The Mediterranean basin countries are considered secondary centres of tomato diversification. However, information on phenotypic and allelic variation of local tomato materials is still limited. Here we report on the evaluation of the largest traditional tomato collection, which includes 1499 accessions from Southern Europe. Analyses of 70 traits revealed a broad range of phenotypic variability with different distributions among countries, with the culinary end use within each country being the main driver of tomato diversification. Furthermore, eight main tomato types (phenoclusters) were defined by integrating phenotypic data, country of origin, and end use. Genome-wide association study (GWAS) meta-analyses identified associations in 211 loci, 159 of which were novel. The multidimensional integration of phenoclusters and the GWAS meta-analysis identified the molecular signatures for each traditional tomato type and indicated that signatures originated from differential combinations of loci, which in some cases converged in the same tomato phenotype. Our results provide a roadmap for studying and exploiting this untapped tomato diversity.We thank Universitat Illes Balears, the Greek Gene Bank (GGB-NAGREF), Universita degli Studi Mediterranea Reggio Calabria, the CRB-Leg (INRA-GAFL)", the Genebank of CNR-IBBR (Bari, Italy) and ARCA 2010 for seed sharing. CNR-IBBR also acknowledges the seed donors, the Leibniz Institute of Plant Genetics and Crop Plant Research, Maria Cristina Patane (CNR-IBE, Catania, Italy) and La Semiorto Sementi SRL, as well as Mrs. Roberta Nurcato for technical assistance. IBMCP-UPV acknowledges Maurizio Calduch (ALCALAX) for technical assistance and Mario Fon for English grammar editing. This work was supported by European Commission H2020 research and innovation program through TRADITOM grant agreement No.634561, G2P-SOL, grant agreement No. 677379, and HARNESSTOM grant agreement No. 101000716. Clara Pons and Mariola Plazas are grateful to Spanish Ministerio de Ciencia e Innovacion for postdoctoral grants FJCI-2016-29118 and IJC2019-039091I/AEI/10.13039/501100011033; Joan Casals to a Serra Hunter Fellow at Universitat Politècnica de Catalunya.Pons Puig, C.; Casals, J.; Palombieri, S.; Fontanet, L.; Riccini, A.; Rambla Nebot, JL.; Ruggiero, A.... (2022). Atlas of phenotypic, genotypic and geographical diversity present in the European traditional tomato. Horticulture Research. 9:1-16. https://doi.org/10.1093/hr/uhac112116

LSST: from Science Drivers to Reference Design and Anticipated Data Products

(Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg$^2$ field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5$\sigma$ point-source depth in a single visit in $r$ will be $\sim 24.5$ (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg$^2$ with $\delta<+34.5^\circ$, and will be imaged multiple times in six bands, $ugrizy$, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg$^2$ region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to $r\sim27.5$. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie

The Trichoderma koningii aggregate species

The morphological concept of Trichoderma koningii is found to include several species that differ from each other in details of phenotype (including conidium morphology, growth rate) and biogeography. Phylogenetic analysis utilizing partial sequences of the translation-elongation factor 1 alpha (tef1), as well as fragments of actin and calmodulin genes, indicate that phenotypic characters typical of T. koningii evolved independently in three well-separated main lineages. Combined molecular and phenotype data lead to the development of a taxonomy with the recognition of twelve taxonomic species and one variety within the three lineages. These lineages include: (1) T. koningii and T. ovalisporum and the new species T. caribbaeum var. caribbaeum, T. caribbaeum var. aequatoriale, T. dorotheae, T. dingleyae, T. intricatum, T. koningiopsis, T. petersenii and T. taiwanense; (2) the new species T. rogersonii and T. austrokoningii, and (3) the new anamorph T. stilbohypoxyli

Impact of COVID-19 on global burn care.

Worldwide, different strategies have been chosen to face the COVID-19-patient surge, often affecting access to health care for other patients. This observational study aimed to investigate whether the standard of burn care changed globally during the pandemic, and whether country´s income, geographical location, COVID-19-transmission pattern, and levels of specialization of the burn units affected reallocation of resources and access to burn care. The Burn Care Survey is a questionnaire developed to collect information on the capacity to provide burn care by burn units around the world, before and during the pandemic. The survey was distributed between September and October 2020. McNemar`s test analyzed differences between services provided before and during the pandemic, χ2 or Fisher's exact test differences between groups. Multivariable logistic regression analyzed the independent effect of different factors on keeping the burn units open during the pandemic. The survey was completed by 234 burn units in 43 countries. During the pandemic, presence of burn surgeons did not change (p = 0.06), while that of anesthetists and dedicated nursing staff was reduced (<0.01), and so did the capacity to manage patients in all age groups (p = 0.04). Use of telemedicine was implemented (p < 0.01), collaboration between burn centers was not. Burn units in LMICs and LICs were more likely to be closed, after adjustment for other factors. During the pandemic, most burn units were open, although availability of standard resources diminished worldwide. The use of telemedicine increased, suggesting the implementation of new strategies to manage burns. Low income was independently associated with reduced access to burn care. [Abstract copyright: Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.

Structure-function studies of an engineered scaffold protein derived from stefin A. I: Development of the SQM variant

Non-antibody scaffold proteins are used for a range of applications, especially the assessment of protein–protein interactions within human cells. The search for a versatile, robust and biologically neutral scaffold previously led us to design STM (stefin A triple mutant), a scaffold derived from the intracellular protease inhibitor stefin A. Here, we describe five new STM-based scaffold proteins that contain modifications designed to further improve the versatility of our scaffold. In a step-by-step approach, we introduced restriction sites in the STM open reading frame that generated new peptide insertion sites in loop 1, loop 2 and the N-terminus of the scaffold protein. A second restriction site in ‘loop 2’ allows substitution of the native loop 2 sequence with alternative oligopeptides. None of the amino acid changes interfered significantly with the folding of the STM variants as assessed by circular dichroism spectroscopy. Of the five scaffold variants tested, one (stefin A quadruple mutant, SQM) was chosen as a versatile, stable scaffold. The insertion of epitope tags at varying positions showed that inserts into loop 1, attempted here for the first time, were generally well tolerated. However, N-terminal insertions of epitope tags in SQM had a detrimental effect on protein expression