Improved limits on photon velocity oscillations

The mixing of the photon with a hypothetical sterile paraphotonic state would have consequences on the cosmological propagation of photons. The absence of distortions in the optical spectrum of distant Type Ia supernov\ae allows to extend by two orders of magnitude the previous limit on the Lorentz-violating parameter $\delta$ associated to the photon-paraphoton transition, extracted from the abscence of distortions in the spectrum of the cosmic microwave background. The new limit is consistent with the interpretation of the dimming of distant Type Ia supernov\ae as a consequence of a nonzero cosmological constant. Observations of gamma-rays from active galactic nuclei allow to further extend the limit on $\delta$ by ten orders of magnitude.Comment: 10 pages, 4 Postscript figures, use epsfig, amssym

The reproducibility of SfM algorithms to produce detailed Digital Surface Models: the example of PhotoScan applied to a high-alpine rock glacier

In geomorphology, PhotoScan is a software that is used to produce Digital Surface Models (DSMs). It constructs 3D environments from 2D imagery (often taken by Unmanned Aerial Vehicles (UAV)) based on Structure-from-Motion (SfM) and Multi- View Stereo (MVS) principles. However, unpublished computer-vision algorithms used, contain random elements which can affect the accuracy of the outputs. For this letter, ten model runs with identical inputs were performed on UAV imagery of a rock glacier to analyse the magnitude of the variation between the different model outputs. This variation was quantified calculating the standard deviation of each cell value in the respective DSMs and derivatives (curvature). Places with steep slope gradients have considerably more DSM variation (up to 10 cm) but stay within the range of the model’s accuracy (10 vertical cm) for 88 – 96% of the area. The edges of the model also show a larger variability (0.10 – 3 m), related to a lower number of overlapping images. These results should be accounted for when performing a geomorphological research at centimetre scale using PhotoScan, especially in areas with a complex relief. Using medium-quality runs, additional oblique viewpoints and respecting a minimum of five overlapping images can minimize the software’s variations

BIOTEX-biosensing textiles for personalised healthcare management.

Textile-based sensors offer an unobtrusive method of continually monitoring physiological parameters during daily activities. Chemical analysis of body fluids, noninvasively, is a novel and exciting area of personalized wearable healthcare systems. BIOTEX was an EU-funded project that aimed to develop textile sensors to measure physiological parameters and the chemical composition of body fluids, with a particular interest in sweat. A wearable sensing system has been developed that integrates a textile-based fluid handling system for sample collection and transport with a number of sensors including sodium, conductivity, and pH sensors. Sensors for sweat rate, ECG, respiration, and blood oxygenation were also developed. For the first time, it has been possible to monitor a number of physiological parameters together with sweat composition in real time. This has been carried out via a network of wearable sensors distributed around the body of a subject user. This has huge implications for the field of sports and human performance and opens a whole new field of research in the clinical setting

Capsicumicine, a new bioinspired peptide from red peppers prevents staphylococcal biofilm in vitro and in vivo via a matrix anti-assembly mechanism of action

Staphylococci are pathogenic biofilm-forming bacteria and a source of multidrug resistance and/or tolerance causing a broad spectrum of infections. These bacteria are enclosed in a matrix that allows them to colonize medical devices, such as catheters and tissues, and that protects against antibiotics and immune systems. Advances in antibiofilm strategies for targeting this matrix are therefore extremely relevant. Here, we describe the development of the Capsicum pepper bioinspired peptide “capsicumicine.” By using microbiological, microscopic, and nuclear magnetic resonance (NMR) approaches, we demonstrate that capsicumicine strongly prevents methicillin-resistant Staphylococcus epidermidis biofilm via an extracellular “matrix anti-assembly” mechanism of action. The results were confirmed in vivo in a translational preclinical model that mimics medical device-related infection. Since capsicumicine is not cytotoxic, it is a promising candidate for complementary treatment of infectious diseases

Red pepper peptide coatings control Staphylococcus epidermidis adhesion and biofilm formation

Medical devices (indwelling) have greatly improved healthcare. Nevertheless, infections related to the use of these apparatuses continue to be a major clinical concern. Biofilms form on surfaces after bacterial adhesion, and they function as bacterial reservoirs and as resistance and tolerance factors against antibiotics and the host immune response. Technological strategies to control biofilms and bacterial adhesion, such as the use of surface coatings, are being explored more frequently, and natural peptides may promote their development. In this study, we purified and identified antibiofilm peptides from Capsicum baccatum (red pepper) using chromatography- tandem mass spectrometry, MALDI-MS, MS/MS and bioinformatics. These peptides strongly controlled biofilm formation by Staphylococcus epidermidis, the most prevalent pathogen in device-related infections, without any antibiotic activity. Furthermore, natural peptide-coated surfaces dislayed effective antiadhesive proprieties and showed no cytotoxic effects against different representative human cell lines. Finally, we determined the lead peptide predicted by Mascot and identified CSP37, which may be useful as a prime structure for the design of new antibiofilm agents. Together, these results shed light on natural Capsicum peptides as a possible antiadhesive coat to prevent medical device colonization

Homology-directed repair in rodent zygotes using Cas9 and TALEN engineered proteins

International audienceThe generation of genetically-modified organisms has been revolutionized by the development of new genome editing technologies based on the use of gene-specific nucleases, such as meganucleases, ZFNs, TALENs and CRISPRs-Cas9 systems. The most rapid and cost-effective way to generate genetically-modified animals is by microinjection of the nucleic acids encoding gene-specific nucleases into zygotes. However, the efficiency of the procedure can still be improved. In this work we aim to increase the efficiency of CRISPRs-Cas9 and TALENs homology-directed repair by using TALENs and Cas9 proteins, instead of mRNA, microinjected into rat and mouse zygotes along with long or short donor DNAs. We observed that Cas9 protein was more efficient at homology-directed repair than mRNA, while TALEN protein was less efficient than mRNA at inducing homology-directed repair. Our results indicate that the use of Cas9 protein could represent a simple and practical methodological alternative to Cas9 mRNA in the generation of genetically-modified rats and mice as well as probably some other mammals

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

Análise descritiva das internações hospitalares por traumatismo do olho e da órbita ocular em caráter de urgência no Brasil

Head and facial injuries account for 50% of trauma deaths, with common causes being motorcycle accidents and violence. Orbital fractures are complex due to their three-dimensional anatomy and the main ophthalmological manifestations include low visual acuity, hyphema and ophthalmoplegia, resulting from edema, hemorrhage and various injuries. This work aims to analyze the epidemiological profile of hospital morbidity due to trauma to the eye and ocular orbit as an emergency in Brazil. This quantitative and retrospective ecological study used data from SIH/SUS in DATASUS, collected in June 2024. Variables included region, age group, sex and color/race. During the period analyzed, 13,230 hospitalizations were recorded. The distribution by age group shows that the majority of hospitalizations occurred between 20 and 49 years old (49.61%). Regarding color/race, 38.84% of patients were mixed race, 32.31% white, 4.43% black, 1.18% yellow, and 0.14% indigenous. The highest frequency of hospitalizations was among male individuals, mixed race, aged between 30 and 39 years old, residing in the Southeast region.Lesões na cabeça e face representam 50% das mortes por trauma, com causas comuns sendo acidentes motociclísticos e violência. Fraturas orbitais são complexas devido à anatomia tridimensional e as principais manifestações oftalmológicas incluem baixa acuidade visual, hifema e oftalmoplegia, decorrentes de edemas, hemorragias e lesões diversas. Este trabalho visa analisar o perfil epidemiológico da morbidade hospitalar por traumatismo do olho e órbita ocular em caráter de urgência no Brasil. Este estudo ecológico quantitativo e retrospectivo utilizou dados do SIH/SUS no DATASUS, coletados em junho de 2024. As variáveis incluíram região, faixa etária, sexo e cor/raça. No período analisado, foram registradas 13.230 internações. A distribuição por faixa etária mostra que a maioria das internações ocorreu entre 20 e 49 anos (49,61%). Quanto à cor/raça, 38,84% dos pacientes eram pardos, 32,31% brancos, 4,43% pretos, 1,18% amarelos, e 0,14% indígenas. A maior frequência de internações foi entre indivíduos do sexo masculino, de cor parda, com idade entre 30 e 39 anos, residentes na região Sudeste.&nbsp;&nbsp