20 GHz instantaneous bandwidth RF spectrum analyzer with high time-resolution

International audienceWe report on the experimental demonstration of a multi-gigahertz bandwidth RF spectrum analyzer exhibiting a resolution below 20 MHz, based on spectral hole burning in a rare-earth ion-doped crystal. To be compatible with demanding real-time spectrum monitoring applications, our demonstrator is designed to reach a high time resolution. For this purpose, we implemented the so-called "rainbow" architecture in which the spectral components of the incoming signal are angularly separated by the crystal, and are then acquired with a pixelated photodetector. The Tm 3+ :YAG crystal is programmed with a semiconductor DFB laser which frequency scan is servo-controlled and synchronized with the angular scan of a resonant galvanometric mirror, while a high-speed camera is used to acquire the spectra. In the perspective of future implementation within a system, the crystal is cooled below 4 K with a closed-cycle cryostat. With this setup, we have been able to monitor and record the spectrum of complex microwave signals over an instantaneous bandwidth above 20 GHz, with a time resolution below 100 µs, 400 resolvable frequency components and a probability of intercept of 100 %

Role of the K+-Cl- Cotransporter KCC2a Isoform in Mammalian Respiration at Birth

In central respiratory circuitry, synaptic excitation is responsible for synchronizing neuronal activity in the different respiratory rhythm phases, whereas chloride-mediated inhibition is important for shaping the respiratory pattern itself. The potassium chloride cotransporter KCC2, which serves to maintain low intraneuronal Cl- concentration and thus render chloride-mediated synaptic signaling inhibitory, exists in two isoforms, KCC2a and KCC2b. KCC2 is essential for functional breathing motor control at birth, but the specific contribution of the KCC2a isoform remains unknown. Here, to address this issue, we investigated the respiratory phenotype of mice deficient for KCC2a. In vivo plethysmographic recordings revealed that KCC2a-deficient pups at P0 transiently express an abnormally low breathing rate and a high occurrence of apneas. Immunostainings confirmed that KCC2a is normally expressed in the brainstem neuronal groups involved in breathing (pre-Botzinger complex, parafacial respiratory group, hypoglossus nucleus) and is absent in these regions in the KCC2a(-/-) mutant. However, in variously reduced in vitro medullary preparations, spontaneous rhythmic respiratory activity is similar to that expressed in wild-type preparations, as is hypoglossal motor output, and no respiratory pauses are detected, suggesting that the rhythm-generating networks are not intrinsically affected in mutants at P0. In contrast, inhibitory neuromodulatory influences exerted by the pons on respiratory rhythmogenesis are stronger in the mutant, thereby explaining the breathing anomalies observed in vivo. Thus, our results indicate that the KCC2a isoform is important for establishing proper breathing behavior at the time of birth, but by acting at sites that are extrinsic to the central respiratory networks themselves.Peer reviewe

Trends in COVID-Related Activity in Sentinel Family Medicine Practices: An Observational Study

Objectives: During the COVID pandemic, data collected in family medicine were scarce. The COVID-FM project aimed to monitor trends of COVID-related activity in family medicine practices of the canton of Vaud, Switzerland, during the year 2021.Methods: Practitioners were invited to join an ad hoc sentinel surveillance system. Online data collection was based on daily activity reports and monthly questionnaires. Participants categorized daily counts of consultations and phone calls into predefined categories. Data were reported and discussed on a weekly basis with public health authorities.Results: On the target of 50 physicians, 37 general physicians from 32 practices finally constituted the COVID-FM sentinel network, contributing to 901 practice-weeks of surveillance in family medicine and 604 in paediatrics. In paediatrics, COVID-related activity corresponded mostly to COVID-19 diagnostic consultations (2911/25990 face-to-face consultations = 11.2%) while in family medicine, other COVID-related topics—such as questions on vaccination—predominated (4143/42221 = 9.8%).Conclusion: COVID-related consultations constituted an important part of primary care practices’ activity in 2021. Monitoring COVID-related activity in primary care provided health authorities with valuable information to guide public health action

Novos periódicos científicos: o caso do Laboratório de Periódicos Científicos UFSC

The creation of new scientific journals is a challenge for institutions and editors. This paper aims to describe the periodicals of the Laboratory; detail the performance of each title; and reflect on the conditions for the creation of new titles. The methodology is the application of a checklist based on the periodic evaluation criteria to analyze the problems of the papers and the issues. The results show that the Incubator has 8 journals. The main problems identified are: the maintenance of periodicity; the authors’ formation and affiliation identification in the articles; the keywords formatting; and the division of articles into sections. The conclusion shows the need to be careful in creating new titles, because the difficulty with maintenance is underestimated by editors and publishers.A criação de periódicos científicos é um desafio para instituições e editores. Este trabalho tem como objetivos: descrever os periódicos do Laboratório; detalhar o desempenho de cada título; e refletir sobre as condições de criação de novos títulos. A metodologia usada é a aplicação de um checklist elaborado com base nos critérios de avaliação de periódicos para analisar os problemas dos artigos e dos fascículos. Os resultados mostram que a Incubadora tem oito periódicos. Os principais problemas encontrados nos periódicos são: a manutenção da periodicidade; a identificação da formação e filiação dos autores nos artigos; a formatação das palavras-chave; e a divisão dos artigos em seções. A conclusão mostra a necessidade de cuidado na criação de novos títulos, pois a dificuldade com a manutenção é subestimada pelos editores e instituições

Galactosaminogalactan, a New Immunosuppressive Polysaccharide of Aspergillus fumigatus

A new polysaccharide secreted by the human opportunistic fungal pathogen Aspergillus fumigatus has been characterized. Carbohydrate analysis using specific chemical degradations, mass spectrometry, 1H and 13C nuclear magnetic resonance showed that this polysaccharide is a linear heterogeneous galactosaminogalactan composed of α1-4 linked galactose and α1-4 linked N-acetylgalactosamine residues where both monosacharides are randomly distributed and where the percentage of galactose per chain varied from 15 to 60%. This polysaccharide is antigenic and is recognized by a majority of the human population irrespectively of the occurrence of an Aspergillus infection. GalNAc oligosaccharides are an essential epitope of the galactosaminogalactan that explains the universal antibody reaction due to cross reactivity with other antigenic molecules containing GalNAc stretches such as the N-glycans of Campylobacter jejuni. The galactosaminogalactan has no protective effect during Aspergillus infections. Most importantly, the polysaccharide promotes fungal development in immunocompetent mice due to its immunosuppressive activity associated with disminished neutrophil infiltrates

Comparative Analysis of ESBL-Positive Escherichia coli isolates from Animals and Humans from the UK, the Netherlands and Germany

The putative virulence and antimicrobial resistance gene contents of extended spectrum β-lactamase (ESBL)-positive E. coli (n=629) isolated between 2005 and 2009 from humans, animals and animal food products in Germany, The Netherlands and the UK were compared using a microarray approach to test the suitability of this approach with regard to determining their similarities. A selection of isolates (n=313) were also analysed by multilocus sequence typing (MLST). Isolates harbouring blaCTX-M-group-1 dominated (66%, n=418) and originated from both animals and cases of human infections in all three countries; 23% (n=144) of all isolates contained both blaCTX-M-group-1 and blaOXA-1-like genes, predominantly from humans (n=127) and UK cattle (n=15). The antimicrobial resistance and virulence gene profiles of this collection of isolates were highly diverse. A substantial number of human isolates (32%, n=87) did not share more than 40% similarity (based on the Jaccard coefficient) with animal isolates. A further 43% of human isolates from the three countries (n=117) were at least 40% similar to each other and to five isolates from UK cattle and one each from Dutch chicken meat and a German dog; the members of this group usually harboured genes such as mph(A), mrx, aac(6’)-Ib, catB3, blaOXA-1-like and blaCTX-M-group-1. forty-four per cent of the MLST-typed isolates in this group belonged to ST131 (n=18) and 22% to ST405 (n=9), all from humans. Among animal isolates subjected to MLST (n=258), only 1.2% (n=3) were more than 70% similar to human isolates in gene profiles and shared the same MLST clonal complex with the corresponding human isolates. The results suggest that minimising human-to-human transmission is essential to control the spread of ESBL-positive E. coli in humans

Relating bars with the environment in the nearby Universe

We study the correlation between the fraction of barred spiral galaxies and environmental parameters of galaxies to understand in which environments the bars are more commonly found. For this purpose we apply the Blanton et al. technique to a sample of spiral galaxies drawn from the Nair & Abraham catalogue. Our results agree with previous findings in which the fraction of barred galaxies is almost insensitive to environment.Comment: 4 pages, 1 figure, accepted in MNRAS Letter

Action versus Result-Oriented Schemes in a Grassland Agroecosystem: A Dynamic Modelling Approach

Effects of agri-environment schemes (AES) on biodiversity remain controversial. While most AES are action-oriented, result-oriented and habitat-oriented schemes have recently been proposed as a solution to improve AES efficiency. The objective of this study was to compare action-oriented, habitat-oriented and result-oriented schemes in terms of ecological and productive performance as well as in terms of management flexibility. We developed a dynamic modelling approach based on the viable control framework to carry out a long term assessment of the three schemes in a grassland agroecosystem. The model explicitly links grazed grassland dynamics to bird population dynamics. It is applied to lapwing conservation in wet grasslands in France. We ran the model to assess the three AES scenarios. The model revealed the grazing strategies respecting ecological and productive constraints specific to each scheme. Grazing strategies were assessed by both their ecological and productive performance. The viable control approach made it possible to obtain the whole set of viable grazing strategies and therefore to quantify the management flexibility of the grassland agroecosystem. Our results showed that habitat and result-oriented scenarios led to much higher ecological performance than the action-oriented one. Differences in both ecological and productive performance between the habitat and result-oriented scenarios were limited. Flexibility of the grassland agroecosystem in the result-oriented scenario was much higher than in that of habitat-oriented scenario. Our model confirms the higher flexibility as well as the better ecological and productive performance of result-oriented schemes. A larger use of result-oriented schemes in conservation may also allow farmers to adapt their management to local conditions and to climatic variations

Canine idiopathic chronic hepatitis

Canine idiopathic hepatitis is a common disease, categorized histologically by presence of hepatocellular apoptosis or necrosis, a variable mononuclear or mixed inflammatory cell infiltrate, regeneration and fibrosis. Clinical signs are vague and non-specific, but there are known breed, age and gender predispositions. Results of clinical pathology are non-specific, but usually include elevations in liver enzymes and function impairment; a liver biopsy is required for diagnosis. Management involves around the use of an anti-inflammatory dose of glucocorticoids and other supportive and symptomatic therapies including ursodeoxycholic acid, antioxidants, diuretics, and diet. The prognosis is variable, but there are known prognostic indicators, especially the presence of portal hypertensio