Experimental acoustic scene analysis using One-Eighth spherical fraction microphone array

This paper investigates the performance of one-eighth Spherical Fraction Microphone Array through experimental measurement to analyze acoustic scenes in one-eighth of space. The array geometry is designed to be placed in a room corner at the junction of three acoustically rigid walls. Two prototypes are built with 8 and 16 microphones, respectively. The sampling strategy is discussed and a spatial aliasing analysis is carried out both analytically and by numerical simulations. The array performances are evaluated through Spherical Fraction Beamforming (SFB). This approach is based on the decomposition of the acoustic pressure field in a rigid bounded domain. The localization angular error and Directivity Index criterion are evaluated for both arrays. In a first experiment, the arrays are mounted in an eighth of space built inside an anechoic room. The results are compared with simulation and show consistency. The theoretical limitations of SFB in a rigid bounded one-eighth of space are retrieved experimentally. These limitations are also observed in a real configuration: an office room. Further investigations on SFB are also conducted in the case of a virtual scene constructed with two sound sources.

Consumption of alcohol-based hand rub in French nursing homes: results from a nationwide survey, 2018-2019

This study assessed the hand hygiene performance in French nursing homes using the consumption of alcohol-based hand rubs (AHRs) as a surrogate. Nursing homes from the 17 French regions were contacted to collect their AHR consumption and occupancy in 2018 and 2019. A total of 1290 nursing homes from 15 French regions participated in the survey. The estimated median number of hand hygiene actions per resident-day was 1.48 (interquartile range: 1.04-2.03) in 2018 and 1.60 (1.10-2.26) in 2019. A significantly higher AHR consumption was observed in public nursing homes with an infection control team or link nurse.

Clinical implementation of deep-learning based auto-contouring tools-Experience of three French radiotherapy centers

Deep-learning (DL)-based auto-contouring solutions have recently been proposed as a convincing alternative to decrease workload of target volumes and organs-at-risk (OAR) delineation in radiotherapy planning and improve inter-observer consistency. However, there is minimal literature of clinical implementations of such algorithms in a clinical routine. In this paper we first present an update of the state-of-the-art of DL-based solutions. We then summarize recent recommendations proposed by the European society for radiotherapy and oncology (ESTRO) to be followed before any clinical implementation of artificial intelligence-based solutions in clinic. The last section describes the methodology carried out by three French radiation oncology departments to deploy CE-marked commercial solutions. Based on the information collected, a majority of OAR are retained by the centers among those proposed by the manufacturers, validating the usefulness of DL-based models to decrease clinicians' workload. Target volumes, with the exception of lymph node areas in breast, head and neck and pelvic regions, whole breast, breast wall, prostate and seminal vesicles, are not available in the three commercial solutions at this time. No implemented workflows are currently available to continuously improve the models, but these can be adapted/retrained in some solutions during the commissioning phase to best fit local practices. In reported experiences, automatic workflows were implemented to limit human interactions and make the workflow more fluid. Recommendations published by the ESTRO group will be of importance for guiding physicists in the clinical implementation of patient specific and regular quality assurances.

Consommations d’antibiotiques pendant la première vague COVID-19 dans les établissements de santé

Introduction

Lors de la première vague de l’épidémie de COVID-19, la réduction d’activité des établissements de santé (ES), notamment en chirurgie, a pu entraîner un moindre recours aux antibiotiques. Toutefois, l’accueil de nombreux patients atteints de COVID-19 a engendré la prescription de traitements antibiotiques visant à prévenir ou traiter des (suspicions de) surinfections bactériennes. Les consommations d’antibiotiques au premier trimestre 2020 (début de première vague) ont été comparées à celles du deuxième trimestre (pic de la première vague) afin d’estimer l’impact de l’épidémie sur l’utilisation d’antibiotiques.

Matériels et méthodes

Les consommations d’antibiotiques à visée systémique dispensés dans les services d’hospitalisation complète ont été recueillies pour la période du 1^er janvier au 31 mars 2020 (T1) puis du 1^er avril au 30 juin 2020 (T2), dans des ES volontaires participant à la surveillance nationale SPARES, et ayant indiqué avoir accueilli ou non des patients COVID-19. Elles ont été exprimées en nombre de doses définies journalières (DDJ) pour 1000 journées d’hospitalisation (JH) et comparées entre T1 et T2 dans les secteurs d’activité clinique de réanimation, médecine et soins de suite et réadaptation (SSR) (test de Wilcoxon des rangs signés).

Résultats

Dans les 118 ES ayant accueilli des patients COVID-19 (C+) en T1 et T2 et les 75 ES n’en ayant pas accueilli (C−), l’activité en nombre de JH avait diminué de 14 % et 13 % respectivement. La consommation globale d’antibiotique était plus faible en T2 par rapport à T1 dans 35 secteurs de réanimation C+ (−19 %), 72 secteurs de médecine C+ (−9 %) et 25 secteurs de médecine C− (−19 %), ainsi que dans 37 SSR C− (−14 %). En réanimation, les consommations d’azithromycine, ceftriaxone, cefotaxime et amoxicilline–acide clavulanique étaient significativement plus faibles en T2 et celle de ceftazidime significativement plus élevée. La consommation d’antibiotiques était plus élevée en T2 dans 43 secteurs de SSR C+ (+6 %), avec une consommation de ceftriaxone significativement plus élevée.

Conclusion

Globalement, la pression de sélection antibiotique semble avoir été plus faible en T2 dans les ES volontaires ayant fourni des données de consommation par secteur d’activité clinique, qu’ils aient accueilli ou non des patients COVID-19. Cette tendance peut être liée à la réduction d’activité liée, d’une part, aux déprogrammations, et d’autre part, au confinement qui a réduit le nombre d’infections nécessitant potentiellement une hospitalisation. De plus, la mobilisation des comités anti-infectieux a pu conduire à la diffusion de recommandations de bon usage des antibiotiques pour les patients COVID-19 avant même la parution de l’avis du HCSP en juin. Toutefois, s’agissant de données agrégées de dispensation et non de données individuelles d’administration, un effet stockage en T1 ne peut être écarté. L’effet à moyen terme sur les résistances bactériennes reste à évaluer.

An Integrated Biophysical Model for Predicting the Clinical Pharmacokinetics of Transdermally Delivered Compounds

The delivery of therapeutic drugs through the skin is a promising alternative to oral or parenteral delivery routes because dermal drug delivery systems (D³S) offer unique advantages such as controlled drug release over sustained periods and a significant reduction in first-pass effects, thus reducing the required dosing frequency and level of patient noncompliance. Furthermore, D³S find applications in multiple therapeutic areas, including drug repurposing. This article presents an integrated biophysical model of dermal absorption for simulating the permeation and absorption of compounds delivered transdermally. The biophysical model is physiologically/biologically inspired and combines a holistic model of healthy skin with whole-body physiology-based pharmacokinetics through dermis microcirculation. The model also includes the effects of chemical penetration enhancers and hair follicles on transdermal transport. The model-predicted permeation and pharmacokinetics of select compounds were validated using in vivo data reported in the literature. We conjecture that the integrated model can be used to gather insights into the permeation and systemic absorption of transdermal formulations (including cosmetic products) released from novel depots and optimize delivery systems. Furthermore, the model can be adapted to diseased skin with parametrization and structural adjustments specific to skin diseases.

Automation in radiotherapy treatment planning: Examples of use in clinical practice and future trends for a complete automated workflow

Modern radiotherapy treatment planning is a complex and time-consuming process that requires the skills of experienced users to obtain quality plans. Since the early 2000s, the automation of this planning process has become an important research topic in radiotherapy. Today, the first commercial automated treatment planning solutions are available and implemented in a growing number of clinical radiotherapy departments. It should be noted that these various commercial solutions are based on very different methods, implying a daily practice that varies from one center to another. It is likely that this change in planning practices is still in its infancy. Indeed, the rise of artificial intelligence methods, based in particular on deep learning, has recently revived research interest in this subject. The numerous articles currently being published announce a lasting and profound transformation of radiotherapy planning practices in the years to come. From this perspective, an evolution of initial training for clinical teams and the drafting of new quality assurance recommendations is desirable.

Multiple stressors shape invertebrate assemblages and reduce their trophic niche: A case study in a regulated stream

Few studies have addressed how the diversity of basal resources change with stream regulation and the potential consequences on river biota. We sampled invertebrates above and below a series of dams, over two years, at both downwelling and upwelling zones. In each zone, we recorded the daily temperature and flow variations, estimated the algal development, measured the available resources, and analysed carbon and nitrogen stable isotope compositions of the invertebrate community. The number of hydrological pulses were typically higher below the dams than above the dams especially during high-flow periods whereas the groundwater outlets had minor effects on invertebrate assemblages. Invertebrate abundance, richness and diversity tended to decrease below the dams. Co-inertia analysis showed that flow and temperature variations, and eutrophication explained most of the variance in the invertebrate assemblages, which comprised a higher number of resilient taxa below than above the dams. The proportions of pesticide-sensitive invertebrates were lower below the dams and ovoviviparous and more generalist taxa were prominent. We did not observe the expected CPOM decrease and FPOM increase downstream. Accordingly, the proportions of each functional feeding group were remarkably similar above and below the dams despite the long distance between the sectors (>100 kms). The diversity of basal resources used within assemblages progressively increased downstream above dams. In contrast, the diversity of resources used by organisms below the dams decreased from upstream to downstream suggesting a significant influence of flow regulation on aquatic food webs. Finally, the shorter trophic chains for the invertebrate assemblages below the dams suggests that the effects of stream regulation and eutrophication induced a simplification of food webs. To our knowledge, this study is the first to connect taxonomic and functional trait changes in response to multiple stressors with the associated modifications in isotopic niches within aquatic invertebrate assemblages.

CONTEXT

Understanding how stream regulation and associated anthropogenic pressures act on aquatic assemblages and trophic niches is necessary to guide management actions.

GOAL

We aimed to investigate the functional responses (traits and trophic niches) of aquatic invertebrate assemblages to stream regulation and eutrophication.

METHODS

We used univariate and multivariate analyses to compare the invertebrate assemblages above and below the dams and to assess the contributions of hydrology (including groundwater supplies to the river), temperature and eutrophication to the variability in the composition of invertebrate assemblages. We also considered the relative utilization of a selected set of traits describing invertebrate resilience, resistance and specialization to address the potential functional effects of stream regulation on invertebrate assemblages. Finally, carbon and nitrogen isotope analyses allowed us to characterize the length and width of invertebrate assemblage food webs as related to the availability and diversity of basal resources.

RESULTS

Invertebrate abundance and richness generally decreased below the dams, with the highest impacts on insect taxa. Co-inertia analysis showed that stream regulation and eutrophication were main drivers of the aquatic invertebrate assemblages. The analysis separated the sites above and below the dams according to flow and temperature variation, whereas eutrophication appeared as a secondary stressor that separated the sites within each sector. Furthermore, the series of dams resulted in (i) a higher proportion of resilient (e.g., multivoltine) and resistant (ovoviviparous) taxa and a majority of generalists in assemblages below dams, (ii) an impact on the classical dynamics of CPOM (decrease) and FPOM (increase) sources from upstream to downstream, and (iii) a reduction in the diversity of resource use and in the trophic chain length of invertebrate assemblages below dams. The cooler and less oxygenated upwelling zones had lower invertebrate abundance; however, contrary to our expectation, the variation in the groundwater supply did not affect the composition of epigean invertebrate assemblages.

CONCLUSION

This study provides insights about the impacts of flow regime alteration and eutrophication on food webs that may have been caused by regulation of permanent streams. To our knowledge, this is the first to connect taxonomic and functional trait changes in response to multiple stressors with the associated modifications in energy fluxes in aquatic invertebrate assemblages. This study suggests that bed stability, which is associated with a reduction in channel mobility below the dams and with moderate eutrophication, may provide the shelter and resources that can locally favour invertebrate assemblage dynamics and lessen the effects of flow regulation. In addition, the study suggests that the biological trait-based approach and isotope analysis are complementary approaches for addressing ecosystem functioning. The relative utilization of traits indicates the functional potential of aquatic invertebrate assemblages to face multiple stressors whereas isotope analysis is an expression of the actual effect of the stressors on the trophic structure of aquatic invertebrate assemblages.

Patterns of antibiotic use in hospital-acquired infections

BACKGROUND

Monitoring the use of antimicrobials in hospitalized patients is critical owing to the risk of resistance selection. This study aimed to describe the patterns of antimicrobial prescription for the most frequent healthcare-associated infections (HAIs) in France, relating drugs and microbiological data.

METHODS

We used data from the 2017 point-prevalence survey of HAI and antimicrobial use in France, a large nationally representative sample survey of inpatients. We sought unambiguous correspondence between individual indications of antibiotic regimen and HAI sites to determine which molecules were directed towards which pathogen, considering its resistance profile.

RESULTS

Among 75,698 adult patients from 401 hospitals, 5.1% had an active HAI and 4.3% were being treated for an HAI. The two most frequent antibiotic indications were lower respiratory tract (LRTI, 27.7%) and urinary tract infections (UTI, 18.4%). For LRTI, the most prescribed antibiotic was amoxicillin-clavulanic acid (27.6%) and most frequently isolated pathogens (each accounting for around 17% of isolates) were Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. Meticillin-resistant S. aureus LRTI was more likely to be treated with linezolid. For UTI, ofloxacin, ceftriaxone, amoxicillin/co-amoxiclav were most-prescribed (∼13% each) and E. coli predominantly isolated (52.0%). Extended-spectrum beta-lactamase-producing E. coli UTI were more likely treated by fosfomycin, pivmecillinam or ertapenem.

CONCLUSIONS

This study provides a baseline of antimicrobial use in relation to microbiological information in patients with the most common HAIs. These results can serve to direct future efforts in antimicrobial stewardship. Our work could be extended to a broader population, notably in Europe where similar surveys have been conducted.

Prevalence and impact of patient suicide in psychiatrists: Results from a national French web-based survey

BACKGROUND

Patient suicide (PS) is known to be a frequent and challenging occupational hazard for mental health professionals. No study previously explored the prevalence and impact of PS in a large sample of French psychiatrists.

METHOD

A national web-based survey was performed between September and December 2019 to assess (a) the prevalence of the exposure to PS, (b) the emotional, traumatic and professional impacts of PS, and (c) the perceived support in the aftermath of PS in French psychiatrists. Participants were contacted through email to answer the online 62-item questionnaire, including a measure of traumatic impact through the Impact of Event Scale-Revised. Emotional and professional impacts and perceived support were assessed through dedicated items.

RESULTS

A total of 764 psychiatrists fully completed the survey. Of them, 87.3% reported an exposure to PS and 13.7% reported PTSD symptoms afterward. Guilt, sadness and shock were the most frequent emotions. Among the exposed psychiatrists, 15.1% have temporarily considered changing their career path. The most emotionally distressing PS occurred during their ten first years of practice or during residency. A total of 37.1% of respondents felt unsupported and 50.4% reported that no team meeting had been organized in the aftermath. The feeling of responsibility for the death was strongly associated with negative impacts.

CONCLUSION

Our results entail considerations to prevent negative mental health outcomes in psychiatrists after PS. Notably, our results advocate for the implementation of educational programs during psychiatric residency and postvention programs in healthcare settings to effectively help psychiatrists in dealing with PS.

Estimation of heart rate from tracheal sounds recorded for the sleep apnea syndrome diagnosis

Obstructive sleep apnea is a common sleep disorder with a high prevalence and often accompanied by significant snoring activity. To diagnose this condition, polysomnography is the standard method, where a neck microphone could be added to record tracheal sounds. These can then be used to study the characteristics of breathing, snoring or apnea. In addition cardiac sounds, also present in the acquired data, could be exploited to extract heart rate. The paper presents new algorithms for estimating heart rate from tracheal sounds, especially in very loud snoring environment. The advantage is that it is possible to reduce the number of diagnostic devices, especially for compact home applications. Three algorithms are proposed, based on optimal filtering and cross-correlation. They are tested firstly on one patient presenting significant pathology of apnea syndrome, with a recording of 509 min. Secondly, an extension to a database of 16 patients is proposed (16 hours of recording). When compared to a reference ECG signal, the final results obtained from tracheal sounds reach an accuracy of 81% to 98% and an RMS error from 1.3 to 4.2 bpm, according to the level of snoring and to the considered algorithm.

Gathering at the top? Environmental controls of microplastic uptake and biomagnification in freshwater food webs

Microplastics are ubiquitous in the environment, with high concentrations being detected now also in river corridors and sediments globally. Whilst there has been increasing field evidence of microplastics accumulation in the guts and tissues of freshwater and marine aquatic species, the uptake mechanisms of microplastics into freshwater food webs, and the physical and geological controls on pathway-specific exposures to microplastics, are not well understood. This knowledge gap is hampering the assessment of exposure risks, and potential ecotoxicological and public health impacts from microplastics. This review provides a comprehensive synthesis of key research challenges in analysing the environmental fate and transport of microplastics in freshwater ecosystems, including the identification of hydrological, sedimentological and particle property controls on microplastic accumulation in aquatic ecosystems. This mechanistic analysis outlines the dominant pathways for exposure to microplastics in freshwater ecosystems and identifies potentially critical uptake mechanisms and entry pathways for microplastics and associated contaminants into aquatic food webs as well as their risk to accumulate and biomagnify. We identify seven key research challenges that, if overcome, will permit the advancement beyond current conceptual limitations and provide the mechanistic process understanding required to assess microplastic exposure, uptake, hazard, and overall risk to aquatic systems and humans, and provide key insights into the priority impact pathways in freshwater ecosystems to support environmental management decision making.

Energy transport and light propagation mechanisms in organic single crystals

Unambiguous information about spatiotemporal exciton dynamics in three-dimensional nanometer- to micrometer-sized organic structures is difficult to obtain experimentally. Exciton dynamics can be modified by annihilation processes, and different light propagation mechanisms can take place, such as active waveguiding and photon recycling. Since these various processes and mechanisms can lead to similar spectroscopic and microscopic signatures on comparable time scales, their discrimination is highly demanding. Here, we study individual organic single crystals grown from thiophene-based oligomers. We use time-resolved detection-beam scanning microscopy to excite a local singlet exciton population and monitor the subsequent broadening of the photoluminescence (PL) signal in space and on pico- to nanosecond time scales. Combined with Monte Carlo simulations, we were able to exclude photon recycling for our system, whereas leakage radiation upon active waveguiding leads to an apparent PL broadening of about 20% compared to the initial excitation profile. Exciton-exciton annihilation becomes important at high excitation fluence and apparently accelerates the exciton dynamics leading to apparently increased diffusion lengths. At low excitation fluences, the spatiotemporal PL broadening results from singlet exciton diffusion with diffusion lengths of up to 210 nm. Surprisingly, even in structurally highly ordered single crystals, the transport dynamics is subdiffusive and shows variations between different crystals, which we relate to varying degrees of static and dynamic electronic disorders.

Effects of azacitidine in 93 patients with IDH1/2 mutated acute myeloid leukemia/myelodysplastic syndromes: a French retrospective multicenter study

Isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) mutations in Myeloid Neoplams (MNs) exhibit DNA hypermethylation via 2-hydroxyglutarate (2HG) over-production. Clinical impact of azacitidine (AZA) remains inconsistent in IDH1/2-mutated MNs and the potential of serum 2HG as a suitable marker of response to AZA is unknown. To address these questions, we retrospectively analyzed 93 MNs patients (78 AML, 11 MDS, 4 CMML) with IDH1/2 mutations treated with AZA. After a median of 5 cycles of AZA, overall response rate was 28% (including 15% complete remission) and median OS was 12.3 months (significantly shorter in AML compared to MDS/CMML patients). In multivariate analysis of AML patients, DNMT3A mutation was associated with shorter OS while IDH1/2 mutation subtypes had no independent impact. No difference was observed in serum 2HG levels upon AZA treatment between responding and refractory patients suggesting that serum 2HG cannot be used as a surrogate marker of AZA response.

3D reconstructions, 4D imaging and postprocessing with CT in musculoskeletal disorders: Past, present and future

Three-dimensional (3D) imaging and post processing are common tasks used daily in many disciplines. The purpose of this article is to review the new postprocessing tools available. Although 3D imaging can be applied to all anatomical regions and used with all imaging techniques, its most varied and relevant applications are found with computed tomography (CT) data in musculoskeletal imaging. These new applications include global illumination rendering (GIR), unfolded rib reformations, subtracted CT angiography for bone analysis, dynamic studies, temporal subtraction and image fusion. In all of these tasks, registration and segmentation are two basic processes that affect the quality of the results. GIR simulates the complete interaction of photons with the scanned object, providing photorealistic volume rendering. Reformations to unfold the rib cage allow more accurate and faster diagnosis of rib lesions. Dynamic CT can be applied to cinematic joint evaluations a well as to perfusion and angiographic studies. Finally, more traditional techniques, such as minimum intensity projection, might find new applications for bone evaluation with the advent of ultra-high-resolution CT scanners. These tools can be used synergistically to provide morphologic, topographic and functional information and increase the versatility of CT.