892 research outputs found
Confined photon modes with triangular symmetry in hexagonal microcavities in 2D photonic Crystals
We present theoretical and experimental studies of the size and thickness
dependencies of the optical emission spectra from microcavities with hexagonal
shape in films of two-dimensional photonic crystal. A semiclassical plane-wave
model, which takes into account the electrodynamic properties of quasi-2D
planar photonic microcavity, is developed to predict the eigenfrequencies of
the confined photon modes as a function of both the hexagon-cavity size and the
film thickness. Modes with two different symmetries, triangular and hexagonal,
are critically analyzed. It is shown that the model of confined photon modes
with triangular symmetry gives a better agreement between the predicted
eigenmodes and the observed resonances.Comment: 14 pages, 6 figure
The Influence of Infection and Colonization on Outcomes in Inpatients With COVID-19 : Are We Forgetting Something?
The COVID-19 epidemic has been a great challenge to health systems and especially hospitals. A prospective observational epidemiological study was planned as of February 26, 2020 in a tertiary hospital in the Valencia region. The total number of patients followed up with complete information during the first year was 2,448. Among other variables, the comorbidities of the patients were collected (and grouped in the Charson index), the stay in the intensive care unit (ICU), the co-infections, and the colonizations. Data on nosocomial infections due to said virus were also collected. The median days from the onset of symptoms to diagnosis were 4 + 4.6, while an additional 4.4 days had to pass for the patients to be admitted to the ICU. The factors associated with a higher risk of death were those with coinfection, especially with Candida auris [odds ratio (OR): 4.6], a situation that also occurred in the ICU (OR: 3.18). Charlson Index comorbidity and C. auris colonization were also very important both in general hospitalization and in the ICU
RSVP-TE Extensions to Provide Guarantee of Service to MPLS 1
Abstract. Independent Quality of Service (QoS) models need to be set up in IP and ATM integration and they are difficult to coordinate. This gap is bridged when MultiProtocol Label Switching (MPLS) is used for this purpose. We propose Guarantee of Service (GoS) to improve performance of privileged flows in congested MPLS networks. We first discuss the GoS requirements for the use in conjunction with MPLS. Then we propose a minimum set of extensions to RSVP-TE that allow signaling of GoS information across the MPLS domain
Versatile Graphene-Based Platform for Robust Nanobiohybrid Interfaces
Technologically useful and robust graphene-based interfaces for devices
require the introduction of highly selective, stable, and covalently bonded
functionalities on the graphene surface, whilst essentially retaining the
electronic properties of the pristine layer. This work demonstrates that highly
controlled, ultrahigh vacuum covalent chemical functionalization of graphene
sheets with a thiol-terminated molecule provides a robust and tunable platform
for the development of hybrid nanostructures in different environments. We
employ this facile strategy to covalently couple two representative systems of
broad interest: metal nanoparticles, via S-metal bonds, and thiol-modified DNA
aptamers, via disulfide bridges. Both systems, which have been characterized by
a multi-technique approach, remain firmly anchored to the graphene surface even
after several washing cycles. Atomic force microscopy images demonstrate that
the conjugated aptamer retains the functionality required to recognize a target
protein. This methodology opens a new route to the integration of high-quality
graphene layers into diverse technological platforms, including plasmonics,
optoelectronics, or biosensing. With respect to the latter, the viability of a
thiol-functionalized chemical vapor deposition graphene-based solution-gated
field-effect transistor array was assessed
Results of the implementation of a virtual microscope in a course of histology
[EN] The course of Anatomy and Histology is studied in the first year of Dentistry
at the University Cardenal Herrera CEU (Alfara del Patriarca, Spain). Its
practices consist on choose freely six different tissue samples and draw their
most representative features. These practices were made by optical
microscopy until 2014, and in 2015 was introduced the virtual microscope
exclusively. The aim of the study is to test whether this new teaching method
has improved the quality of exercise and the understanding shown by
students. First, the best exercises of both years were chosen, and from them
some drawings from the same tissue were compared. Some tissues which
samples for optical microscope were hard to obtain, were drawn for the very
first time thanks to the virtual microscope. Also, with the virtual microscopy
the drawings contained more details and definition. The understanding of the
structures improved, shown by a more functional, detailed and defined vision
of the tissues. The labels of the virtual microscope helped to the self-study
and avoided the loss of unnoticed structures. In conclusion, replacement of
optical microscope by the virtual microscope is a teaching improvement and
facilitates student learning.Alegre-MartÃnez, A.; MartÃnez-MartÃnez, MI.; Alfonso Sanchez, JL.; Morales Suárez-Varela, MM.; Llopis Gonzalez, A. (2016). Results of the implementation of a virtual microscope in a course of histology. En 2nd. International conference on higher education advances (HEAD'16). Editorial Universitat Politècnica de València. 169-176. https://doi.org/10.4995/HEAD16.2015.2626OCS16917
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Engineering protein assemblies with allosteric control via monomer fold-switching
The macromolecular machines of life use allosteric control to self-assemble, dissociate and change shape in response to signals. Despite enormous interest, the design of nanoscale allosteric assemblies has proven tremendously challenging. Here we present a proof of concept of allosteric assembly in which an engineered fold switch on the protein monomer triggers or blocks assembly. Our design is based on the hyper-stable, naturally monomeric protein CI2, a paradigm of simple two-state folding, and the toroidal arrangement with 6-fold symmetry that it only adopts in crystalline form. We engineer CI2 to enable a switch between the native and an alternate, latent fold that self-assembles onto hexagonal toroidal particles by exposing a favorable inter-monomer interface. The assembly is controlled on demand via the competing effects of temperature and a designed short peptide. These findings unveil a remarkable potential for structural metamorphosis in proteins and demonstrate key principles for engineering protein-based nanomachinery.This work was supported by the European Research Council (grant ERC-2012-ADG-323059 to V.M.) and by the PRODESTECH network funded through the CONSOLIDER program from the Spanish Government (grant CSD2009-00088). L.A.C. acknowledges support from Ministry of Economy and Competitiveness through grants BIO2016-78768-P and RYC-2013-13197. V.M. acknowledges additional support from the W.M.Keck Foundation and from the CREST Center for Cellular and Biomomolecular Machines (grant NSF-CREST-1547848). J.M.V. acknowledges additional support from Ministry of Economy and Competitiveness through grant BFU2016-75984.Peer reviewe
Wettability, polarity and water absorption of Quercus ilex leaves: effect of leaf side and age
Plant trichomes play important protective functions and may have a major influence on leaf surface wettability. With the aim of gaining insight into trichome structure, composition and function in relation to water-plant surface interactions, we analyzed the adaxial and abaxial leaf surface of Quercus ilex L. (holm oak) as model. By measuring the leaf water potential 24 h after the deposition of water drops on to abaxial and adaxial surfaces, evidence for water penetration through the upper leaf side was gained in young and mature leaves. The structure and chemical composition of the abaxial (always present) and adaxial (occurring only in young leaves) trichomes were analyzed by various microscopic and analytical procedures. The adaxial surfaces were wettable and had a high degree of water drop adhesion in contrast to the highly unwettable and water repellent abaxial holm oak leaf sides. The surface free energy, polarity and solubility parameter decreased with leaf age, with generally higher values determined for the abaxial sides. All holm oak leaf trichomes were covered with a cuticle. The abaxial trichomes were composed of 8% soluble waxes, 49% cutin, and 43% polysaccharides. For the adaxial side, it is concluded that trichomes and the scars after trichome shedding contribute to water uptake, while the abaxial leaf side is highly hydrophobic due to its high degree of pubescence and different trichome structure, composition and density. Results are interpreted in terms of water-plant surface interactions, plant surface physical-chemistry, and plant ecophysiology
Identification of Importin 8 (IPO8) as the most accurate reference gene for the clinicopathological analysis of lung specimens
<p>Abstract</p> <p>Background</p> <p>The accurate normalization of differentially expressed genes in lung cancer is essential for the identification of novel therapeutic targets and biomarkers by real time RT-PCR and microarrays. Although classical "housekeeping" genes, such as GAPDH, HPRT1, and beta-actin have been widely used in the past, their accuracy as reference genes for lung tissues has not been proven.</p> <p>Results</p> <p>We have conducted a thorough analysis of a panel of 16 candidate reference genes for lung specimens and lung cell lines. Gene expression was measured by quantitative real time RT-PCR and expression stability was analyzed with the softwares <it>GeNorm </it>and <it>NormFinder</it>, mean of |ΔCt| (= |Ct Normal-Ct tumor|) ± SEM, and correlation coefficients among genes. Systematic comparison between candidates led us to the identification of a subset of suitable reference genes for clinical samples: IPO8, ACTB, POLR2A, 18S, and PPIA. Further analysis showed that IPO8 had a very low mean of |ΔCt| (0.70 ± 0.09), with no statistically significant differences between normal and malignant samples and with excellent expression stability.</p> <p>Conclusion</p> <p>Our data show that IPO8 is the most accurate reference gene for clinical lung specimens. In addition, we demonstrate that the commonly used genes GAPDH and HPRT1 are inappropriate to normalize data derived from lung biopsies, although they are suitable as reference genes for lung cell lines. We thus propose IPO8 as a novel reference gene for lung cancer samples.</p
Suppressive Antibiotic Therapy in Prosthetic Joint Infections: A Multicentre Cohort Study
Objectives: The aim was to describe the effectiveness of suppressive antibiotic treatment (SAT) in routine clinical practice when used in situations in which removal of a prosthetic implant is considered essential for the eradication of an infection, and it cannot be performed.
Methods: This was a descriptive retrospective and multicentre cohort study of prosthetic joint infection (PJI) cases managed with SAT. SAT was considered to have failed if a fistula appeared or persisted, if debridement was necessary, if the prosthesis was removed due to persistence of the infection or if uncontrolled symptoms were present.
Results: In total, 302 patients were analysed. Two hundred and three of these patients (67.2%) received monotherapy. The most commonly used drugs were tetracyclines (39.7% of patients) (120/302) and cotrimoxazole (35.4% of patients) (107/302). SAT was considered successful in 58.6% (177/302) of the patients (median time administered, 36.5 months; IQR 20.75-59.25). Infection was controlled in 50% of patients at 5 years according to Kaplan-Meier analysis. Resistance development was documented in 15 of 65 (23.1%) of the microbiologically documented cases. SAT failure was associated with age <70 years (sub-hazard ratio (SHR) 1.61, 95% CI 1.1-2.33), aetiology other than Gram-positive cocci (SHR 1.56, 95% CI 1.09-2.27) and location of the prosthesis in the upper limb (SHR 2.4, 95% CI 1.5-3.84). SAT suspension was necessary due to adverse effects in 17 of 302 patients (5.6%).
Conclusions: SAT offers acceptable results for patients with PJI when surgical treatment is not performed or when it fails to eradicate the infection
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