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Appropriate Usage of Face Masks to Prevent SARS-CoV-2: Sharpening the Messaging Amid the COVID-19 Pandemic.
Practical computational advantage from the quantum switch on a generalized family of promise problems
The quantum switch is a quantum computational primitive that provides
computational advantage by applying operations in a superposition of orders. In
particular, it can reduce the number of gate queries required for solving
promise problems where the goal is to discriminate between a set of properties
of a given set of unitary gates. In this work, we use Complex Hadamard matrices
to introduce more general promise problems, which reduce to the known Fourier
and Hadamard promise problems as limiting cases. Our generalization loosens the
restrictions on the size of the matrices, number of gates and dimension of the
quantum systems, providing more parameters to explore. In addition, it leads to
the conclusion that a continuous variable system is necessary to implement the
most general promise problem. In the finite dimensional case, the family of
matrices is restricted to the so-called Butson-Hadamard type, and the
complexity of the matrix enters as a constraint. We introduce the ``query per
gate'' parameter and use it to prove that the quantum switch provides
computational advantage for both the continuous and discrete cases. Our results
should inspire implementations of promise problems using the quantum switch
where parameters and therefore experimental setups can be chosen much more
freely.Comment: 14 pages, 5 figures; more detailed Sections 4 and 5, added new
references for section 5, other minor change
Optimal estimation of high-dimensional unitary transformations
We propose an estimation procedure for -dimensional unitary
transformations. For , the unitary transformations close to the identity
are estimated saturating the quantum Cram\'er-Rao bound. For , the
estimation of all unitary transformations is also optimal with some prior
information. We show through numerical simulations that, even in the absence of
prior information, two-dimensional unitary transformations can be estimated
with greater precision than by means of standard quantum process tomography.Comment: 8+14 pages, 6 figure
Cryptococcosis in Atlántico, Colombia: an approximation of the prevalence of this mycosis and the distribution of the etiological agent in the environment
Geoenvironmental Analysis of Oil Extraction Activities in Urban and Rural Zones of Santa Elena Province, Ecuador
From an environmental viewpoint, oil wells can be considered a potential source of pollution when improperly managed. The Santa Elena province (Ecuador), located on the Pacific coast, currently has a residual crude oil extraction compared to production generated in the Amazon region of the country. However, this activity in the coastal zone is very near to urban and rural populations. Therefore, a detailed influence analysis of these wells on the environment is necessary. This work aims to analyse, from a geoenvironmental perspective, the oil wells impact located in a pilot zone (urban and rural) of the oil field studied and, complementarily, to describe their incidence on the community and territory. The methodological process includes (i) oil wells compilation and inventory within the study zone and selection of a pilot zone; (ii) contaminating factors identification generated by the wells infrastructure (mechanical and territorial) and their current state of activity (production or abandoned); (iii) environmental impacts analysis generated through the development of a cause-effect matrix and, finally, the evaluation of a method and results found through a focus group technique. The results reflect a negative impact on the land cover and vegetative-animal environment in the vicinity of the wells, caused by the continuous release of gases, metallic oxidation and bituminous exhumation. The overall impacts interpretation compiled indicates that comprehensive action is needed at the wells to control and minimise them. The implementation of new environmental strategies through zoning can help to achieve adequate land-use planning, thus combining the safe and sustainable use of the resource with the development of other community activities (urbanisation, tourism, industry, agriculture and fishing) and environmental protection.This work was carried out in collaboration with the ‘Peninsula Santa Elena Geopark Project’ with code no. 91870000.0000.381017, and ‘Factores Geoambientales de los pozos petroleros y su incidencia en el desarrollo territorial en los cantones Salinas y La Libertad de la provincia de Santa Elena’, with code no: 91870000.0000.385428, by UPSE University. Support for the project was also provided by the ‘Registry of geological and mining heritage and its impact on the defence and preservation of geodiversity in Ecuador’, academic research project by ESPOL University, CIPAT-01-2018
Classical Swine Fever Virus p7 Protein Interacts with Host Protein CAMLG and Regulates Calcium Permeability at the Endoplasmic Reticulum
We have previously shown that Classical Swine Fever Virus (CSFV) p7 is an essential nonstructural protein with a viroporin activity, a critical function in the progression of virus infection. We also identified p7 domains and amino acid residues critical for pore formation. Here, we describe how p7 specifically interacts with host protein CAMLG, an integral ER transmembrane protein involved in intracellular calcium release regulation and signal response generation. Detection of interaction as well as the identification of p7 areas mediating interaction with CAMLG was performed by yeast two-hybrid. p7-CAMLG interaction was further confirmed by confocal microscopy in eukaryotic cells, co-expressing both proteins. Mutant forms of p7 having substituted native residues identified as mediating interaction with CAMLG showed a decreased co-localization compared with the native forms of p7. Furthermore, it is shown that native p7, but not the mutated forms of p7 that fail to interact with CAMLG, efficiently mediates calcium permeability in the ER. Interestingly, viruses harboring some of those mutated forms of p7 have been previously shown to have a significantly decreased virulence in swine.ARS/USDA-University of Connecticut SCA# 58-1940-1-190 and ARS/USDA-University of the Basque Country NACA#8064-32000-056-18S
Focal accumulation of aromaticity at the CDRH3 loop mitigates 4E10 polyreactivity without altering its HIV neutralization profile
Broadly neutralizing antibodies (bnAbs) against HIV-1 are frequently associated with the presence of autoreactivity/polyreactivity, a property that can limit their use as therapeutic agents. The bnAb 4E10, targeting the conserved Membrane proximal external region (MPER) of HIV-1, displays almost pan-neutralizing activity across globally circulating HIV-1 strains but exhibits nonspecific off-target interactions with lipid membranes. The hydrophobic apex of the third complementarity-determining region of the heavy chain (CDRH3) loop, which is essential for viral neutralization, critically contributes to this detrimental effect. Here, we have replaced the aromatic/hydrophobic residues from the apex of the CDRH3 of 4E10 with a single aromatic molecule through chemical modification to generate a variant that preserves the neutralization potency and breadth of 4E10 but with reduced autoreactivity. Collectively, our study suggests that the localized accumulation of aromaticity by chemical modification provides a pathway to ameliorate the adverse effects triggered by the CDRH3 of anti-HIV-1 MPER bnAbs.This study was supported by the following Grants: European Commission (790012 SI H2020-MSCA-IF-2017) (E.R.); US NIAID, NIH grant R01 AI143563 (M.B. Z.); James B. Pendleton Charitable Trust (M.B.Z.); JSPS grant 20H03228 (J. M.M.C.); Spanish MCIU (RTI2018-095624-B-C21; MCIU/AEI/FEDER, UE) (J.L.N.), Basque Government (IT1196-19) (J.L.N.). C.E. acknowledges funding from Medical Research Council (grant number MC_UU_12010/unit programs G0902418 and MC_UU_12025), Wolfson Foundation, Deutsche Forschungsgemeinschaft (Excellence Cluster Balance of the Microverse, Collaborative Research Center 1278 Polytarget), Leibniz Association (Leibniz Campus Infectooptics), Wellcome Institutional Strategic Support Fund, Oxford internal funds (EPA Cephalosporin Fund and John Fell Fund), and support from the Micron Oxford Advanced Bioimaging Unit (Wellcome Trust funding 107457/Z/15/Z). This work was also supported by the Platform Project for Supporting Drug Discovery and Life Science Research [Basis for Supporting Innovative Drug Discovery and Life Science Research (BINDS)] from AMED (JP21am0101091). S.I. received a predoctoral fellowship from the BasqueGovernment. P.C. would like to acknowledge the University of the Basque Country (DOCREC18/01), the Basque Government (POS_2018_1_0066) and the European Commission (H2020-MSCA-IF-2019-ST project 892232 FILM-HIV) for funding his position. This research was also supported by the CIFAR Azrieli Global Scholar program (J-P.J.), the Ontario Early Researcher Awards program (J-P.J.), and the Canada Research Chairs program (J-P.J.). Part of the biophysical data presented in this manuscript were collected at the Hospital for Sick Children Structural & Biophysical Core facility supported by the Canada Foundation for Innovation and Ontario Research Fund
Affinity for the Interface Underpins Potency of Antibodies Operating In Membrane Environments
The contribution of membrane interfacial interactions to recognition of membrane-embedded antigens by antibodies is currently unclear. This report demonstrates the optimization of this type of antibodies via chemical modification of regions near the membrane but not directly involved in the recognition of the epitope. Using the HIV-1 antibody 10E8 as a model, linear and polycyclic synthetic aromatic compounds are introduced at selected sites. Molecular dynamics simulations predict the favorable interactions of these synthetic compounds with the viral lipid membrane, where the epitope of the HIV-1 glycoprotein Env is located. Chemical modification of 10E8 with aromatic acetamides facilitates the productive and specific recognition of the native antigen, partially buried in the crowded environment of the viral membrane, resulting in a dramatic increase of its capacity to block viral infection. These observations support the harnessing of interfacial affinity through site-selective chemical modification to optimize the function of antibodies that target membrane-proximal epitopes.We are grateful to Professor Ueda (Kyushu University) for valuable advice. C.D. acknowledges RES (Red Espanola de Supercomputacio ' n) for providing computational resources. S.I. received a pre-doctoral fellowship from the Basque Government. P.C. acknowledges a research associate contract from the University of the Basque Country (DOCREC18/01) and a postdoctoral fellowship from the Basque Government (POS_2018_1_0066).This study was supported by the following grants: European Commission (790012 SI H2020MSCA-IF-2017 to E.R., J.-P.J., and J.L.N.); US NIAID (NIH) (R01 AI143563 to M.B.Z.); James B. Pendleton Charitable Trust (to M.B.Z.); Grant-in-Aid for Scientific Research on Innovative Areas "Chemistry for Multimolecular Crowding Biosystems, JSPS KAKENHI (JP17H06349 to A.O.); JSPS KAKENHI (15K06962 and 20H03228 to J.M.M.C.); Spanish MINECO (BIO2015-64421R and MINECO/AEI/FEDER, UE to J.L.N.); Spanish MCIU (RTI2018-095624B-C21 and MCIU/AEI/FEDER, UE to J.L.N.); and the Basque Government (IT1196-19) (to J.L.N.). C.E. acknowledges funding from Medical Research Council (MC_UU_12010/unit programs G0902418 and MC_UU_12025), Wolfson Foundation, Deutsche Forschungsgemeinschaft (Research unit 1905, Excellence Cluster Balance of the Microverse, Collaborative Research Centre 1278 Polytarget), Wellcome Institutional Strategic Support Fund, Oxford internal funds (EPA Cephalosporin Fund and John Fell Fund), and support from the Micron Oxford Advanced Bioimaging Unit (Wellcome Trust funding 107457/Z/15/Z). This research was undertaken, in part, thanks to funding from the CIFAR Azrieli Global Scholar program (to J.-P.J.) and the Canada Research Chairs program (950-231604 to J.-P.J.). This work was also supported by the Platform Project for Supporting Drug Discovery and Life Science Research (Basis for Supporting Innovative Drug Discovery and Life Science Research [BINDS] from AMED JP19am0101091)
Whole-genome sequencing to determine origin of multinational outbreak of Sarocladium kiliense bloodstream infections
We used whole-genome sequence typing (WGST) to investigate an outbreak of Sarocladium kiliense bloodstream infections (BSI) associated with receipt of contaminated antinausea medication among oncology patients in Colombia and Chile during 2013-2014. Twenty-five outbreak isolates (18 from patients and 7 from medication vials) and 11 control isolates unrelated to this outbreak were subjected to WGST to elucidate a source of infection. All outbreak isolates were nearly indistinguishable (≤5 single-nucleotide polymorphisms), and >21,000 single-nucleotide polymorphisms were identified from unrelated control isolates, suggesting a point source for this outbreak. S. kiliense has been previously implicated in healthcare-related infections; however, the lack of available typing methods has precluded the ability to substantiate point sources. WGST for outbreak investigation caused by eukaryotic pathogens without reference genomes or existing genotyping methods enables accurate source identification to guide implementation of appropriate control and prevention measures. © 2016, Centers for Disease Control and Prevention (CDC). All rights reserved
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