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Investigation of Patterned Plasma Etching Processes for HJT-IBC Solar Cells: Keys to Maintaining a High Electronic Quality Surface
No full textInternational audienceWe examine a cell fabrication process involving a novel patterned plasma etching step to define the interdigitatedback-contact (IBC) structure for heterojunction (HJT) crystalline silicon (c-Si) solar cells. In this process, specificplasma surface treatments are necessary to achieve good device performance. X-ray Photoelectron Spectroscopy(XPS) and High-Resolution Transmission Electron Microscopy (HRTEM) are used to investigate the underlyingreasons for the effectiveness of these treatments. Two experimental conditions are explored: (1) etching thehydrogenated nanocrystalline silicon (nc-Si:H) and amorphous silicon (a-Si:H) layers down to c-Si surface beforedepositing the final doped layer, and (2) leaving a >5 nm intrinsic a-Si:H (i-a-Si:H) after etching. In the first case,a gentle NF3 etching step suffices to recover diode-like behavior without S-shape, but results in cells with verylow open-circuit voltage (VOC). In the second case, an additional H2 plasma cleaning step is required to recoverboth diode-like behavior without S-shape and good minority carrier lifetime (and high VOC). XPS analysis revealsthat both NF3 etching and H2 plasma can remove N, F, and O from the interface seen by the patterning plasma,although with different effectiveness for c-Si and a-Si:H surfaces. Critically, avoiding an air break between NF3etching and H2 plasma reduces oxidation at the interface between i-a-Si:H and the final doped layer to background levels, thereby achieving the best device performance. HRTEM provides supporting insights that explainthe necessity of the etching steps and the importance of stopping the etching at the i-a-Si:H layer before reachingthe c-Si surface
Influence of Inhaled Corticosteroids on Voice Quality: A Systematic Review
No full textInternational audienc
Global Trends in CD4 Measurement and Immunosuppression at ART Initiation Among Children With HIV
No full textInternational audienceEligibility for antiretroviral therapy is no longer based on immune criteria. In a global cohort of 97,453 children, between 2005 and 2021, we observed large declines in CD4 measurement, from 51% to 12% among <5 seconds, and from 74% to 20% among those 5–14 years of age. Lack of CD4 testing may negatively affect clinical care and surveillance of severe immune suppression
Evaluation of Muscle Synergy Flexibility Induced by a Muscle Nerve Block in Chronic Stroke Patients
No full textInternational audienceBackground: Drug treatments for gait disorders in post-stroke patients aim to reduce muscular hyperactivity. The analysis of muscle activity is essential to help clinicians understand these disorders. This study aimed to quantify changes in muscle synergies before (PRE) and after (POST) a rectus femoris nerve block. Methods: Gait analysis of 8 post-stroke patients before and immediately after nerve block. Muscle synergies were quantified from electromyographic signals. We have selected the account for variance, which indicates the effectiveness of the synergies, the recruitment selectivity index, which indicates the degree of multiplexing of the synergies, and the recruitment consistency index, which indicates the variability of the synergy activations across gait cycles. Results: A decrease in Variance Account For (VAF) is observed, showing a lack of robustness of the underlying muscle synergies between PRE and POST. We also note that spatial and temporal primitives result in different Index of Recruitment Selectivity (IRS) but similar Index of Recruitment Consistency (IRC) for PRE vs. POST. This shows that the synergies' activations remain consistent across cycles but are more distributed in POST than in PRE. Conclusions: The motor nerve block has not created new muscle synergies of the paretic limb during gait but indicates that there is flexibility in motor organization. This method of quantification may enable clinicians to assess the motor adaptation potential of their post-stroke patients
Perioperative C1-esterase inhibitor therapy to allow transplantation in a highly sensitized lung transplant candidate: three case reports
No full textInternational audienc
Cannabis and mental health in adolescents: changes in associations over 15 years
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A multiplexing system for quantifying oxygen fractionation factors in closed chambers
No full textInternational audienceThe study of isotopic ratios of atmospheric oxygen in fossilized air trapped in ice core bubbles provides information on variations in the hydrological cycle at low latitudes and productivity in the past. However, to refine these interpretations, it is necessary to better quantify fractionation of oxygen in the biological processes such as photosynthesis and respiration. We set up a system of closed biological chambers in which we studied the evolution of elemental and isotopic composition of O2 due to biological processes. To easily replicate experiments, we developed a multiplexing system which we describe here. We compared measurements of elemental and isotopic composition of O2 using two different measurement techniques: optical spectrometry (Optical-Feedback Cavity- Enhanced Absorption Spectroscopy, i.e. OF-CEAS technique), which enables higher temporal resolution and continuous data collection and isotopic ratio mass spectrometry (IRMS) with a flanged air recovery system, thus validating the data analysis conducted through the OF-CEAS technique. As a first application, we investigated isotopic discrimination during respiration and photosynthesis. We conducted a 5-day experiment using maize (Zea mays L.) as model species. The 18O discrimination value for maize during dark plant respiration was determined as - 17.8 ± 0.9 ‰ by IRMS and - 16.1 ± 1.1 ‰ by optical spectrometer. We also found a value attributed to the isotopic discrimination of terrestrial photosynthesis equal to + 3.2 ± 2.6 ‰ by IRMS and + 6.7 ± 3.8 ‰ by optical spectrometer. These findings were consistent with a previous study by Paul et al. (2023)
CHETNA-Brick Sector: Estimating GHG and Pollutant Emissions from Brick Kilns in India Using Sentinel-2 Imagery and Deep Learning
No full textInternational audienceIndia, the world&#8217;s second-largest brick producer, operates over 100,000 kilns. These kilns emit 170 kt of PM2.5 (15% of the national total) and 120 Mt of CO2 (6% of the national total) annually, along with substantial SOx and NOx emissions. Transitioning from traditional Fixed Chimney Bull&#8217;s Trench Kilns (FCBTKs) to cleaner technologies, such as Zigzag Kilns (ZZKs), has the potential to reduce coal consumption by 20% and particulate matter emissions by 70%. However, comprehensive datasets for kiln locations across India remain scarce. This study contributes to the CHETNA project (City-wise High-resolution carbon Emissions Tracking and Nationwide Analysis), which leverages artificial intelligence and advanced datasets to deliver high-resolution, near real-time daily CO2 and air pollutant emissions data for over 100 Indian cities.&#160;To address this gap, we leveraged Sentinel-2 imagery, with a spatial resolution of 10&#8211;20 m, to develop a cost-effective and scalable approach. Most existing studies focus on specific geographic areas, such as northern India, and rely on expensive, high-resolution satellite imagery that is often not readily available, limiting their broader applicability. In contrast, our study represents the first nationwide mapping of brick kilns in India, using openly accessible satellite data and advanced machine learning models.Using a curated dataset of 9,600 geo-tagged labels covering 18,000 km&#178;, we developed a method combining Sentinel-2 imagery with convolutional neural networks (CNN) to detect brick kilns and classify their operational technologies (e.g., FCBTK, Zigzag). Labels were annotated using Google Earth layers on QGIS and validated based on distinct visual features, such as oval or rectangular ochre-colored shapes. The model leverages RGB bands to detect active kilns, while the addition of NIR, SWIR, and NDVI metrics enhances its ability to identify abandoned kilns, often concealed by vegetation, and reduces false positives.The model achieved a precision of 0.90, a recall of 0.89, and an accuracy of 0.91 on the test set. Detected kiln centroids were highly accurate, with precise GPS coordinates matching their actual locations. Nationwide, the model identified 44,000 brick kilns in India for 2022. We benchmarked multiple models to optimize false positive reduction and improve technology classification. Building on these results, we applied the model to neighboring countries in the Indo-Gangetic Plain (IGP), spanning Pakistan, Bangladesh, and parts of Nepal, which also contribute significantly to the brick kiln industry, identifying approximately 20,000 kilns in 2022.Beyond location mapping, we are generating annual gridded emission maps for CO2 and pollutants such as PM2.5, black carbon, and NOx. These maps provide time-series insights into emission trends, reduce uncertainties in carbon and pollutant emissions, quantify reductions achieved through cleaner technologies, and identify regional hotspots. By focusing on underregulated, high-emission sectors like brick kilns, this study offers critical insights for targeted mitigation strategies and sustainable urban planning. It equips policymakers with tools to evaluate regulations and demonstrates the feasibility of using Sentinel-2 imagery for cost-efficient, large-scale monitoring.&#160
Challenges in Defining Clinical Complete Response to Systemic Therapy in Muscle-invasive Bladder Cancer: Insights from the EORTC STARBURST Project
No full textInternational audienc
<i>DMRT1</i> haploinsufficiency leads to secondary infertility in XY male rabbits
No full textInternational audienceAbstract DMRT1 is a key factor in testis development, where it is involved in sex determination and fertility. Mutations in DMRT1 have been described in humans, with patients presenting 46, XY Disorders of Sex Development (46, XY DSD) or infertility. In a previous study, we demonstrated that DMRT1 is a testis-determining factor in rabbits, with DMRT1−/− rabbits exhibiting a male to female XY sex reversal. In this study, we show that DMRT1 haploinsufficiency induces secondary infertility, with XY rabbits presenting oligospermia or even azoospermia at two years of age. We observed that sperm concentration decreases and sperm anomalies increase in DMRT1+/− rabbits at adulthood. Furthermore, spermatogenesis is impacted as early as 4 months (the earliest stage where spermatozoa are detected), with dysregulation of genes involved in spermatid maturation and oocyte/spermatozoa fusion, as well as overexpression of genes involved in the mitosis/meiosis transition of spermatogonial stem cells (SSCs). Finally, DMRT1 haploinsufficiency impacts the earliest stages of germ cell differentiation, with persistent proliferation and pluripotency in the postnatal period. In conclusion, our findings underscore DMRT1 as a crucial factor at various stages of testicular development, and reinforce its role in the multiple phenotypes observed in humans