104 results on '"S. Nicolay"'
Search Results
52. Epidermal inclusion cyst of the perianal region
- Author
-
S Nicolay, A De Schepper, and M Pouillon
- Subjects
Cyst ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Background: A 51-year-old previously healthy woman presented with a perianal mass. The mass has been there for some years and has gradually increased in size ever since with progressive pain when she sits. There was no history of trauma nor injections in this region. Clinically, the mass was not tender and rather soft, with superficially some focal harder spots. A large lipoma was suspected on clinical basis. An ultrasonography and subsequent MRI scan, including sequences following administration of gadolinium contrast medium were performed.
- Published
- 2014
- Full Text
- View/download PDF
53. Lattice-Matched GaN–InAlN Waveguides at $\lambda=1.55\ \mu$m Grown by Metal–Organic Vapor Phase Epitaxy
- Author
-
Daniel Hofstetter, Fabrizio R. Giorgetta, Esther Baumann, J.-F. Carlin, Eric Feltin, F. H. Julien, Sylvain Nicolay, Mauro Mosca, Nicolas Grandjean, Gottfried Strasser, S. Golka, A. Lupu, G. Pozzovivo, A LUPU, F JULIEN, S GOLKA, G POZZOVIVO, G STRASSER, E BAUMANN, F GIORGETTA, D HOFSTETTER, S NICOLAY, MOSCA M, E FELTIN, J - F CARLIN, and N GRANDJEAN
- Subjects
Materials science ,business.industry ,Optical communication ,Cladding (fiber optics) ,Epitaxy ,Lambda ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Metal ,Wavelength ,visual_art ,Lattice (order) ,visual_art.visual_art_medium ,Optoelectronics ,Metalorganic vapour phase epitaxy ,Electrical and Electronic Engineering ,business - Abstract
We report on the demonstration of low-loss, single-mode GaN-InAlN ridge waveguides (WGs) at fiber-optics telecommunication wavelengths. The structure grown by metal-organic vapor phase epitaxy contains AlInN cladding layers lattice-matched to GaN. For slab-like WGs propagation losses are below 3 dB/mm and independent of light polarization. For 2.6-mum-wide WGs the propagation losses in the 1.5- to 1.58-mum spectral region are as low as 1.8 and 4.9 dB/mm for transverse-electric- and transverse-magnetic-polarization, respectively. The losses are attributed to the sidewall roughness and can be further reduced by the optimization of the etching process.
- Published
- 2008
54. Nitride-based heterostructures grown by MOCVD for near- and mid-infrared intersubband transitions
- Author
-
Laurent Nevou, Nicolas Grandjean, Sylvain Nicolay, Marc Ilegems, Mauro Mosca, Raphaël Butté, Maria Tchernycheva, F. H. Julien, Eric Feltin, J.-F. Carlin, M. Mosca, S. Nicolay, E. Feltin, J.‐F. Carlin, R. Butté, M. Ilegem, N. Grandjean, M. Tchernycheva, L. Nevou, and F. H. Julien
- Subjects
Materials science ,Absorption spectroscopy ,Condensed matter physics ,business.industry ,MULTIPLE-QUANTUM WELLS ,MU-M ,Infrared spectroscopy ,chemistry.chemical_element ,Heterojunction ,Surfaces and Interfaces ,Chemical vapor deposition ,Nitride ,Condensed Matter Physics ,Settore ING-INF/01 - Elettronica ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry ,Materials Chemistry ,ABSORPTION ,Optoelectronics ,Metalorganic vapour phase epitaxy ,Electrical and Electronic Engineering ,business ,Indium ,Quantum well - Abstract
Intersubband (lSB) optical absorption in different nitride-based heterostructures grown by metal-organic chemical vapour deposition (MOCVD) is reported. The role of indium in AlInN/GaN multi-quantum wells (MQWs) is investigated. At high concentration (15%) AlInN is quasi lattice-matched to GaN and no cracks appear in the structure. At very low indium concentration (similar to 2%) the material quality is improved without decreasing the ISB transition wavelength with respect to the case of indium-free structures. Different mechanisms of strain relaxation in pure and 2% indium-doped AlN/GaN MQW structures are also investigated. ISB transition wavelengths of 2 urn for AlN/GaN MQWs, and 3 mu n for AlInN/GaN MQWs with 15% of In are achieved. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
- Published
- 2007
55. Intersubband Transitions in Nitride Based Quantum Wells
- Author
-
Nicolay, S., Mauro Mosca, Carlin, J., Feltin, E., Grandjean, N., Ilegems, M., S NICOLAY, MOSCA M, J-F CARLIN, E FELTIN, N GRANDJEAN, and M ILEGEMS
- Published
- 2005
56. Mid-infrared intersubband absorption in lattice-matched AlInN/GaN multiple-quantum wells
- Author
-
Marc Ilegems, Raphaël Butté, Eric Feltin, Mauro Mosca, Maria Tchernycheva, F. H. Julien, J.-F. Carlin, Laurent Nevou, Nicolas Grandjean, Sylvain Nicolay, S NICOLAY, M TCHERNYCHEVA, J-F CARLIN, L NEVOU, E FELTIN, R BUTTE', MOSCA M, FH JULIEN, N GRANDJEAN, and M ILEGEMS
- Subjects
GaN/AlN quantum ,Photoluminescence ,Materials science ,Physics and Astronomy (miscellaneous) ,Condensed matter physics ,Wide-bandgap semiconductor ,Gallium nitride ,quantum dots ,Molecular physics ,Condensed Matter::Materials Science ,chemistry.chemical_compound ,chemistry ,Quantum dot ,Excited state ,Ground state ,Quantum well ,Molecular beam epitaxy - Abstract
We report the observation of midinfrared intersubband (ISB) absorption in nearly lattice-matched AlInNGaN multiple-quantum-wells. A clear absorption peak is observed around 3 μm involving transitions from the conduction band ground state to the first excited state. In addition to ISB absorption, photoluminescence experiments were carried out on lattice- matched AlInNGaN single quantum wells in order to determine the spontaneous polarization discontinuity between GaN and Al0.82 In0.18 N compounds. The experimental value is in good agreement with theoretical predictions. Our results demonstrate that the AlInNGaN system is very promising to achieve crack-free and low dislocation density structures dedicated to intersubband devices in the 2-4 μm wavelength range.
- Published
- 2005
57. Indium surfactant effect on AlN/GaN heterostructures grown by metal-organic vapor-phase epitaxy: Applications to intersubband transitions
- Author
-
M. Ilegems, Mauro Mosca, Nicolas Grandjean, J.-F. Carlin, F. H. Julien, Maria Tchernycheva, L. Nevou, Sylvain Nicolay, Eric Feltin, S NICOLAY, E FELTIN, J-F CARLIN, MOSCA M, L NEVOU, M TCHERNYCHEVA, F H JULIEN, M ILEGEMS, and N GRANDJEAN
- Subjects
GaN/AlN quantum ,Materials science ,Photoluminescence ,Physics and Astronomy (miscellaneous) ,business.industry ,SUPERLATTICES ,Superlattice ,MULTIPLE-QUANTUM WELLS ,MU-M ,chemistry.chemical_element ,quantum dots ,Heterojunction ,RELAXATION ,Gallium nitride ,Epitaxy ,LAYERS ,GAN ,chemistry ,Quantum dot ,Optoelectronics ,business ,Absorption (electromagnetic radiation) ,Quantum well ,Indium - Abstract
We report on a dramatic improvement of the optical and structural properties of AlN/GaN multiple quantum wells (MQWs) grown by metal-organic vapor-phase epitaxy using indium as a surfactant. This improvement is observed using photoluminescence as well as x-ray diffraction. Atomic force microscopy shows different surface morphologies between samples grown with and without In. This is ascribed to a modified relaxation mechanism induced by different surface kinetics. These improved MQWs exhibit intersubband absorption at short wavelength (2 mu m). The absorption linewidth is as low as 65 meV and the absorption coefficient is increased by 85%.
58. Combining the Strengths of MS and NMR in Biochemometrics: A Case Study on Buddleja officinalis .
- Author
-
Wasilewicz A, Areesanan A, Kirchweger B, Nicolay S, Waltenberger E, Beniddir MA, Gründemann C, Rollinger JM, and Grienke U
- Abstract
Biochemometrics has emerged as promising strategy for the targeted identification of bioactive constituents from natural sources. It is based on the correlation of bioactivity data with chemical data to reveal constituents contributing to activity. Providing complementary data and structural information, MS- and NMR-based biochemometric approaches have both been separately applied in the past. The herein presented study is dedicated to the evaluation of a combined MS- and NMR-based biochemometric workflow for the unambiguous identification of bioactives. As an example, a flower extract of Buddleja officinalis Maxim. was selected to unravel bioactive constituents in the context of dry eye disease pathology. While NMR-based biochemometrics relies on heterocovariance analysis (HetCA) of
1 H NMR spectra using the previously established ELINA approach, a biochemometric molecular network was generated for the MS-based approach. Both analyses were performed in parallel and were ultimately combined to increase their power to identify the bioactive constituents from the complex mixture. As a result, phenylethanoid glycosides and triterpene saponins were discovered as main contributors for the antioxidant and cytotoxic effects of the extract. This article illustrates the advantages, opportunities, and limitations of MS and NMR in the context of biochemometrics.- Published
- 2024
- Full Text
- View/download PDF
59. Intuitive moral bias favors the religiously faithful.
- Author
-
Dayer A, Aswamenakul C, Turner MA, Nicolay S, Wang E, Shurik K, and Holbrook C
- Subjects
- Humans, Male, Female, Adult, New Zealand, Religion, United States, Young Adult, Altruism, Religion and Psychology, Middle Aged, Intuition, Adolescent, Morals
- Abstract
Belief in powerful supernatural agents that enforce moral norms has been theoretically linked with cooperative altruism and prosociality. Correspondingly, prior research reveals an implicit association between atheism and extreme antisociality (e.g., serial murder). However, findings centered on associations between lack of faith and moral transgression do not directly address the hypothesized conceptual association between religious belief and prosociality. Accordingly, we conducted two pre-registered experiments depicting a "serial helper" to assess biases related to extraordinary helpfulness, mirroring designs depicting a serial killer used in prior cross-cultural work. In both a predominantly religious society (the U.S., Study 1) and a predominantly secular society (New Zealand, Study 2), we successfully replicated previous research linking atheism with transgression, and obtained evidence for a substantially stronger conceptual association between religiosity and virtue. The results suggest that stereotypes linking religiosity with prosociality are both real and global in scale., (© 2024. The Author(s).)
- Published
- 2024
- Full Text
- View/download PDF
60. Pembrolizumab-associated myositis with striking extraocular muscle contrast enhancement.
- Author
-
Van Doeselaer L, Nicolay S, and De Ridder W
- Published
- 2024
- Full Text
- View/download PDF
61. Impact of Fermentation on the Phytochemical Profile and Bioactivity Characteristics of Aqueous Matricaria recutita L. Root Extracts.
- Author
-
Mailänder LK, Nosrati Gazafroudi K, Greiß M, Lorenz P, Nicolay S, Gründemann C, Stintzing FC, Daniels R, and Kammerer DR
- Subjects
- Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents isolation & purification, Microbial Sensitivity Tests, Gram-Negative Bacteria drug effects, Gram-Positive Bacteria drug effects, Humans, Water chemistry, Animals, Picrates antagonists & inhibitors, Biphenyl Compounds antagonists & inhibitors, Cell Survival drug effects, Plant Roots chemistry, Plant Roots metabolism, Matricaria chemistry, Matricaria metabolism, Plant Extracts chemistry, Plant Extracts pharmacology, Plant Extracts isolation & purification, Fermentation, Antioxidants pharmacology, Antioxidants chemistry, Antioxidants isolation & purification, Antioxidants metabolism, Phytochemicals chemistry, Phytochemicals pharmacology, Phytochemicals isolation & purification, Phytochemicals metabolism
- Abstract
While the flowers of Matricaria recutita L., German chamomile, are widely used for medicinal and cosmetic purposes, little is known about its roots, which are used in complementary medicine for the preparation of aqueous fermented extracts for the treatment of cramps and anxiety. To broaden the understanding of the active principles involved, a model fermentation approach was developed and fermentates were compared to commercially manufactured tinctures. Coumarins and hydroxycinnamates were among the major secondary metabolites characterized using HPLC-MS
n . After six months of fermentation and storage, low-molecular organic acids were detected by GC-MS. Fermentation contributed to the stabilization of antioxidant and radical scavenging activities, which were in a range of about 8-10 mg gallic acid equivalents/g dry weight and 20-24 mg trolox equivalents/g dry weight, determined by Folin-Ciocalteu and DPPH assays, respectively. In addition, antibacterial activities of the extracts against Gram-positive and -negative bacteria increased during the first week of fermentation. Fermentates were neither cytotoxic nor pro- or anti-inflammatory. Thus, fermentation of chamomile roots is a suitable method for the safe production of biofunctional aqueous chamomile root extracts that remain stable without the addition of synthetic preservatives., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)- Published
- 2024
- Full Text
- View/download PDF
62. Potential benefits of Malva sylvestris in dry-eye disease pathology in vitro based on antioxidant, wound-healing and anti-inflammatory properties.
- Author
-
Areesanan A, Nicolay S, Keller M, Zimmermann-Klemd AM, Potterat O, and Gründemann C
- Subjects
- Humans, Antioxidants pharmacology, Plant Extracts pharmacology, Reactive Oxygen Species pharmacology, Anti-Inflammatory Agents pharmacology, Wound Healing, Polyphenols pharmacology, Malva, Dry Eye Syndromes
- Abstract
Dry eye disease (DED) is a common chronic ocular surface disease. Available therapies are effective but often associated with side effects. This study investigates the potential of a Malva sylvestris L. flower extract and two defined preparations, a mucilage and a polyphenol rich fraction, on cells that are essential for the DED pathology. Furthermore, single compounds were isolated and characterised out of the polyphenol fraction. The M. sylvestris extract and its two fractions reduced reactive oxygen species (ROS) in an ultraviolet-induced model and promoted wound healing capacity of HCE-T cells, but only the polyphenol fraction and the flower extract exhibited significant radical scavenging activity. The flower extract and the polyphenol fraction inhibited cytokine secretion (IL-6, TNF-α, IL-8) from HCE-T cells and THP-1 cells. In contrast, the mucilage fraction led to an increase in mediator secretion. The NF-κB activity and calcium influx in THP-1 and Jurkat cells, respectively was decreased by treatment with the flower extract and the polyphenol fraction, whereas the mucilage fraction had no influence on these parameters. Moreover, the flower extract and the mucilage fraction at low concentration could stimulate meibomian gland cells' lipid accumulation. The isolated single compounds showed no effect on analysed parameters, except a coumarin derivative and malvin which showed ROS inhibition effects., Competing Interests: Declaration of Competing Interest All other authors declare no conflict of interest. The funding sponsors had no role in the design, writing and publishing strategy of the study, as well as in collection, analysis, or interpretation of the data., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
63. Exploring Immune Modulatory Effects of Cyclotide-Enriched Viola tricolor Preparations.
- Author
-
Retzl B, Zimmermann-Klemd AM, Winker M, Nicolay S, Gründemann C, and Gruber CW
- Subjects
- Humans, T-Lymphocytes, Plant Extracts pharmacology, Plant Extracts chemistry, Cyclotides chemistry, Viola chemistry, Plants, Medicinal, Inflammatory Bowel Diseases
- Abstract
Viola tricolor is a medicinal plant with documented application as an anti-inflammatory herb. The standard of care for the treatment of inflammatory bowel disease is immunosuppressive therapeutics or biologics, which often have undesired effects. We explored V. tricolor herbal preparations that are rich in an emerging class of phytochemicals with drug-like properties, so-called cyclotides. As an alternative to existing inflammatory bowel disease medications, cyclotides have immunomodulatory properties, and their intrinsic stability allows for application in the gastrointestinal tract, for instance, via oral administration. We optimized the isolation procedure to improve the yield of cyclotides and compared the cellular effects of violet-derived organic solvent-extracts, aqueous preparations, and an isolated cyclotide from this plant on primary human T lymphocytes and macrophages, i.e., cells that are crucial for the initiation and progression of inflammatory bowel disease. The hot water herbal decoctions have a stronger immunosuppressive activity towards proliferation, interferon- γ , and interleukin-21 secretion of primary human T cells than a DCM/MeOH cyclotide-enriched extract, and the isolated cyclotide kalata S appears as one of the active components responsible for the observed effects. This effect was increased by a longer boiling duration. In contrast, the DCM/MeOH cyclotide-enriched extract was more effective in reducing the levels of cytokines interleukin-6, interleukin-12, interleukin-23, tumor necrosis factor- α , and C - X-C motif chemokine ligand 10, secreted by human monocyte-derived macrophages. Defined cyclotide preparations of V. tricolor have promising pharmacological effects in modulating immune cell responses at the cytokine levels. This is important towards understanding the role of cyclotide-containing herbal drug preparations for future applications in immune disorders, such as inflammatory bowel disease., Competing Interests: The authors declare that they have no conflict of interest., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commecial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)
- Published
- 2023
- Full Text
- View/download PDF
64. Identifying barriers to preventive care among First Nations people at risk of lower extremity amputation: a qualitative study.
- Author
-
Wees T, Pandey M, Nicolay S, Windigo J, Bitternose A, and Kopriva D
- Abstract
Background: First Nations people in Canada are overrepresented among those who have undergone nontraumatic lower extremity amputation, and are more likely to be younger, have diabetic foot infections and have no previous revascularization procedures than non-First Nations populations who have undergone lower extremity amputations. We sought to identify access barriers for high-risk First Nations patients, explore patients' experiences with health care systems and identify solutions., Methods: Employing a community participatory research design, we engaged representatives from 2 communities. They assisted with research design and data analysis, and approved the final manuscript. Using a hermeneutic phenomenological approach and purposeful sampling, we conducted 5 semistructured focus groups between August and December 2021 with community health care teams and patients at risk for, or who had previously undergone, a nontraumatic lower extremity amputation., Results: Patients' ( n = 10) and community health care providers' ( n = 18) perspectives indicated that barriers to health care access led to delayed care and increased complications and risk for lower extremity amputations, leading to aggressive procedures upon receiving care. Barriers to care led to negative experiences at urban centres and aggressive procedures created further distrust, leading to care disengagement and poor outcomes. Patients and providers both suggested building stronger partnerships between urban and rural health care providers, improving education for patients and health care providers and identifying innovative strategies to improve patients' overall health., Interpretation: Systemic changes, health promotional program and reliable on-reserve primary care are needed to create equitable access for First Nation patients at risk for lower extremity amputations. The study results imply that health care delivery for First Nations patients at risk for lower extremity amputations can be improved through stronger partnership and communication between urban and community providers, and continued education and cultural competency training for urban health care providers., Competing Interests: Competing interests: Susanne Nicolay reports funding from Pfizer and honoraria from AIMS Saskatchewan and the Health Innovation and Public Policy Conference. She is director of Wellness Wheel. No other competing interests were declared., (© 2023 CMA Impact Inc. or its licensors.)
- Published
- 2023
- Full Text
- View/download PDF
65. Rear textured p-type high temperature passivating contacts and their implementation in perovskite/silicon tandem cells.
- Author
-
Walter A, Kamino BA, Moon SJ, Wyss P, Diaz Leon JJ, Allebé C, Descoeudres A, Nicolay S, Ballif C, Jeangros Q, and Ingenito A
- Abstract
Silicon solar cells based on high temperature passivating contacts are becoming mainstream in the photovoltaic industry. Here, we developed a high-quality boron-doped poly-silicon hole contact. When combined with a co-processed phosphorus-doped poly-silicon electron contact, high-voltage silicon bottom cells could be demonstrated and included in 28.25%-efficient perovskite/Si tandems. The active area was 4 cm
2 active area and the front electrode was screen-printed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2023
- Full Text
- View/download PDF
66. Wellness Wheel Clinics: A First Nation community-partnered care model improving healthcare access, from healthcare providers' perspectives.
- Author
-
Pandey M, Clark M, Beresh E, Nilson S, Kay C, Campbell T, Nicolay S, and Skinner S
- Subjects
- Humans, Aged, Community Health Services, Health Personnel, Indigenous Peoples, Health Services Accessibility, Health Facilities
- Abstract
First Nation people residing in rural and remote communities have limited primary healthcare access, which often affects chronic disease management leading to poor health outcomes. Individuals with lived experiences of chronic disease and substance use, along with health directors, advocated for improved services. Subsequently, an urban healthcare team in partnership with four First Nation communities developed an Outreach clinic to address healthcare access barriers. Established in 2016, this community-led clinic improves primary care access and chronic disease management in First Nation communities. Employing a qualitative research design, interviews were conducted with 15 clinic providers and 9 community members to explore the clinic's 1-year post-implementation impacts. Thematic data analysis indicated that engagement and approval by community leadership, support from Elders and community members and collaboration with existing community healthcare staff were crucial for establishing the Outreach clinic. Initial logistical challenges with space allocation, equipment, medical supplies, funding, staffing, medical records and appointment scheduling were resolved through community consultation and creative solutions. A nurse coordinator ensured continuity of care and was integral to ensuring clients receive seamless care. The commitment of the outreach team and the collective goal of providing client-centered care were instrumental in the clinic's success. In partnership with communities, access to healthcare in First Nation communities can be enhanced by coordinating Outreach clinics through existing community healthcare facilities., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2023
- Full Text
- View/download PDF
67. Understanding and Mitigating the Degradation of Perovskite Solar Cells Based on a Nickel Oxide Hole Transport Material during Damp Heat Testing.
- Author
-
Dussouillez M, Moon SJ, Mensi M, Wolff CM, Liu Y, Yum JH, Kamino BA, Walter A, Sahli F, Lauber L, Christmann G, Sivula K, Jeangros Q, Ballif C, Nicolay S, and Paracchino A
- Abstract
The development of stable materials, processable on a large area, is a prerequisite for perovskite industrialization. Beyond the perovskite absorber itself, this should also guide the development of all other layers in the solar cell. In this regard, the use of NiO
x as a hole transport material (HTM) offers several advantages, as it can be deposited with high throughput on large areas and on flat or textured surfaces via sputtering, a well-established industrial method. However, NiOx may trigger the degradation of perovskite solar cells (PSCs) when exposed to environmental stressors. Already after 100 h of damp heat stressing, a strong fill factor (FF) loss appears in conjunction with a characteristic S-shaped J-V curve. By performing a wide range of analysis on cells and materials, completed by device simulation, the cause of the degradation is pinpointed and mitigation strategies are proposed. When NiOx is heated in an air-tight environment, its free charge carrier density drops, resulting in a band misalignment at the NiOx /perovskite interface and in the formation of a barrier impeding hole extraction. Adding an organic layer between the NiOx and the perovskite enables higher performances but not long-term thermal stability, for which reducing the NiOx thickness is necessary.- Published
- 2023
- Full Text
- View/download PDF
68. Ultrathin ALD Aluminum Oxide Thin Films Suppress the Thermal Shrinkage of Battery Separator Membranes.
- Author
-
da Veiga LP, Jeanguenat C, Lisco F, Li HY, Nicolay S, Ballif C, Ingenito A, and Leon JJD
- Abstract
Thermal runaway is a major safety concern in the applications of Li-ion batteries, especially in the electric vehicle (EV) market. A key component to mitigate this risk is the separator membrane, a porous polymer film that prevents physical contact between the electrodes. Traditional polyolefin-based separators display significant thermal shrinkage (TS) above 100 °C, which increases the risk of battery failure; hence, suppressing the TS up to 180 °C is critical to enhancing the cell's safety. In this article, we deposited thin-film coatings (less than 10 nm) of aluminum oxide by atomic layer deposition (ALD) on three different types of separator membranes. The deposition conditions and the plasma pretreatment were optimized to decrease the number of ALD cycles necessary to suppress TS without hindering the battery performance for all of the studied separators. A dependency on the separator composition and porosity was found. After 100 ALD cycles, the thermal shrinkage of a 15 μm thick polyethylene membrane with 50% porosity was measured to be below 1% at 180 °C, with ionic conductivity >1 mS/cm. Full battery cycling with NMC532 cathodes demonstrates no hindrance to the battery's rate capability or the capacity retention rate compared to that of bare membranes during the first 100 cycles. These results display the potential of separators functionalized by ALD to enhance battery safety and improve battery performance without increasing the separator thickness and hence preserving excellent volumetric energy., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)
- Published
- 2022
- Full Text
- View/download PDF
69. Pet ownership issues encountered by geriatric professionals: Preliminary findings from an interdisciplinary sample.
- Author
-
Bibbo J, Johnson J, Drost JC, Sanders M, and Nicolay S
- Abstract
Pets often factor in older adults' health behaviors and decisions. However, the degree to which issues related to pet ownership are encountered or addressed by professionals working with this population remains unknown. The aim of this study was to identify specific issues stemming from pet ownership professionals had encountered in their work with older adults, people living with dementia, and care partners. An interdisciplinary (e.g., social services and healthcare) sample ( N = 462, 89.13% female, M
age = 53.02, SDage = 12.18) completed an online survey addressing pet ownership issues encountered in their work. Descriptive statistics, t-tests, and repeated measures ANOVAs were used to analyze quantitative data. A conventional content analysis was used to analyze open-ended responses to an item asking about "other" issues encountered in their work with these populations. The professionals estimated 46.29% of clients had been pet owners, 41.23% regularly asked about pets, and 79.22% had encountered issues related to pet ownership. Specific issues raised to the professionals varied by type of client. The professionals reported older adults most often raised getting pet items into the home and concerns about their pets' health. The issues most often raised by people living with dementia to the professionals were planning for the pet due to a housing transition and basic pet care. Care partners focused on basic pet care and planning for the pet due to a housing transition. The professionals themselves most often raised the issues of basic pet care, concerns about falling, and the pets' behavior. Professionals who entered clients' homes were more likely to raise issues stemming from pet ownership compared to those who reported they did not enter clients' homes in their current job, t (429.40) = 5.59, p < 0.00001. The eleven new issues identified by the content analysis (e.g., pets impeding care, people refusing care due to the pet) underscored how the health and wellbeing of people and their pets are linked. The results of this study provide strong evidence that professionals do encounter issues related to pet ownership. Including issues stemming from pet ownership into procedures, policies, and programs is likely to have positive impacts on those served by and working in the geriatric workforce., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Bibbo, Johnson, Drost, Sanders and Nicolay.)- Published
- 2022
- Full Text
- View/download PDF
70. Thermal Analysis of Parylene Thin Films for Barrier Layer Applications.
- Author
-
Buchwalder S, Borzì A, Diaz Leon JJ, Bourgeois F, Nicolier C, Nicolay S, Neels A, Zywitzki O, Hogg A, and Burger J
- Abstract
Biocompatible polymer films demonstrating excellent thermal stability are highly desirable for high-temperature (>250 °C) applications, especially in the bioelectronic encapsulation domain. Parylene, as an organic thin film, is a well-established polymer material exhibiting excellent barrier properties and is often the material of choice for biomedical applications. This work investigated the thermal impact on the bulk properties of four types of parylene films: parylene N, C, VT4, and AF4. The films, deposited using the standard Gorham process, were analyzed at varying annealing temperatures from room temperature up to 450 °C. Thermal properties were identified by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) methods, while X-ray diffraction (XRD) analysis showed the effect of high-temperature exposure on the structural properties. In addition to thermal and structural analysis, the barrier properties were measured through the helium transmission rate (HTR) and the water vapor transmission rate (WVTR). Fluorinated parylene films were confirmed to be exceptional materials for high-temperature applications. Parylene AF4 film, 25um thick, demonstrated excellent barrier performance after 300 °C exposure, with an HTR and a WVTR of 12.18 × 103 cm3 (STP) m−2 day−1 atm−1 and 6.6 g m−2 day−1, respectively.
- Published
- 2022
- Full Text
- View/download PDF
71. PULMONARY NODULE DETECTION IN CHEST CT USING A DEEP LEARNING-BASED RECONSTRUCTION ALGORITHM.
- Author
-
Franck C, Snoeckx A, Spinhoven M, El Addouli H, Nicolay S, Van Hoyweghen A, Deak P, and Zanca F
- Subjects
- Algorithms, Phantoms, Imaging, Radiation Dosage, Tomography, X-Ray Computed, Deep Learning, Radiographic Image Interpretation, Computer-Assisted
- Abstract
This study's aim was to assess whether deep learning image reconstruction (DLIR) techniques are non-inferior to ASIR-V for the clinical task of pulmonary nodule detection in chest computed tomography. Up to 6 (range 3-6, mean 4.2) artificial lung nodules (diameter: 3, 5, 8 mm; density: -800, -630, +100 HU) were inserted at different locations in the Kyoto Kagaku Lungman phantom. In total, 16 configurations (10 abnormal, 6 normal) were scanned at 7.6, 3, 1.6 and 0.38 mGy CTDIvol (respectively 0, 60, 80 and 95% dose reduction). Images were reconstructed using 50% ASIR-V and a deep learning-based algorithm with low (DL-L), medium (DL-M) and high (DL-H) strength. Four chest radiologists evaluated 256 series by locating and scoring nodules on a five-point scale. No statistically significant difference was found among the reconstruction algorithms (p = 0.987, average across readers AUC: 0.555, 0.561, 0.557, 0.558 for ASIR-V, DL-L, DL-M, DL-H)., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
- Full Text
- View/download PDF
72. The Brain-Heart Link: A Case Report of a Critically Located Multiple Sclerosis Lesion in the Brainstem Leading to Recurrent Takotsubo Syndrome.
- Author
-
Risseeuw F, Masrori P, Baar I, Nicolay S, Franssen C, and Willekens B
- Abstract
Various central nervous system (CNS) diseases, including neurovascular and neuroinflammatory diseases, can lead to stress cardiomyopathy, also known as Takotsubo syndrome (TTS). We present a case of a 69-year-old woman with cardiovascular comorbidities, suffering from repeated episodes of TTS and respiratory failure due to a critical lesion in the brainstem, leading to a diagnosis of multiple sclerosis (MS). Despite aggressive treatment, intractable and recurrent symptoms in our patient occurred. Repeated bouts of autonomic dysfunction and respiratory failure ultimately led to installment of palliative care and the patient passing away. TTS should raise suspicion for underlying neurological diseases. Thorough questioning of previous neurological symptoms and extensive neurological workup is warranted. MS should be considered as a trigger of TTS also in elderly patients with cardiovascular risk factors., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Risseeuw, Masrori, Baar, Nicolay, Franssen and Willekens.)
- Published
- 2021
- Full Text
- View/download PDF
73. Conservative Treatment of a Floating Mural Thrombus in the Descending Aorta.
- Author
-
Goedemé J, Berzenji L, Nicolay S, and Hendriks JMH
- Abstract
A 70-year-old woman was referred to the department of thoracic and vascular surgery after a floating mural thrombus was found in the distal aortic arch with extension into the proximal descending aorta. Imaging and clinical examination did not show signs of embolization and treatment with aspirin and low-molecular weight heparin was started. Follow-up after 2 weeks and 6 months showed a complete resolution of the aortic mural thrombus., Competing Interests: The authors declare no conflict of interest related to this article., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).)
- Published
- 2021
- Full Text
- View/download PDF
74. Vague abdominal pain after Roux-en-Y gastric bypass: not always an internal herniation: case report and literature review.
- Author
-
Allaeys T, Dhooghe V, Nicolay S, and Hubens G
- Subjects
- Female, Humans, Postoperative Complications diagnosis, Young Adult, Abdominal Pain etiology, Blind Loop Syndrome diagnosis, Blind Loop Syndrome etiology, Gastric Bypass adverse effects, Obesity surgery, Postoperative Complications etiology
- Abstract
Background: Roux-en-Y gastric bypass is a frequently carried out bariatric procedure, proven to be effective in the management of obesity and its accompanying health issues. Following its popularity, admission to the emergency department for abdominal pain is often seen with known early and late onset causes. We present a case of a young woman with vague abdominal pain years after her gastric bypass, who eventually underwent a resection of a 'candy cane' like biliopancreatic blind loop. Methods: A healthy 23-year-old woman has been suffering of vague abdominal complaints after a gastric bypass procedure 4 years earlier. Postprandial pain, diarrhoea and abdominal distension were present at a daily to weekly basis. Several investigations and management options were administered by surgeons, gastroenterologists as well as endocrinologists. On a performed explorative laparoscopy, a large blind loop at the entero-enteric anastomosis was seen and resected. Results: At current follow-up of 15 months the resection of the candy cane like blind end of the biliopancreatic loop resulted in a complete withdrawal of our patient's symptoms. A tentative diagnosis of bacterial overgrowth in the blind loop was made. Conclusions: Abdominal pain after gastric bypass is a frequent cause of admission to the emergency department. Besides the more serious complications, internal hernia is often withheld as possible diagnosis in the differential diagnosis of late onset, postprandial epigastric pain. This case report highlights another possibility. At initial surgery, a candy cane shaped blind loop should be avoided both at the gastro-jejunal as well as the entero-enteric anastomosis.
- Published
- 2020
- Full Text
- View/download PDF
75. Wellness Wheel Mobile Outreach Clinic: A Community-Led Care Model Improving Access to Care in Indigenous Communities.
- Author
-
Pandey M, Nicolay S, Clark M, Desjarlais V, Clay A, and Skinner S
- Published
- 2020
- Full Text
- View/download PDF
76. Bi-allelic expression of the RyR1 p.A4329D mutation decreases muscle strength in slow-twitch muscles in mice.
- Author
-
Elbaz M, Ruiz A, Nicolay S, Tupini C, Bachmann C, Eckhardt J, Benucci S, Pelczar P, Treves S, and Zorzato F
- Subjects
- Amino Acid Substitution, Animals, Male, Mice, Mice, Mutant Strains, Ryanodine Receptor Calcium Release Channel genetics, Gene Expression Regulation, Muscle Fibers, Slow-Twitch metabolism, Muscle Strength, Mutation, Missense, Ryanodine Receptor Calcium Release Channel biosynthesis
- Abstract
Mutations in the ryanodine receptor 1 ( RYR1 ) gene are associated with several human congenital myopathies, including the dominantly inherited central core disease and exercise-induced rhabdomyolysis, and the more severe recessive phenotypes, including multiminicore disease, centronuclear myopathy, and congenital fiber type disproportion. Within the latter group, those carrying a hypomorphic mutation in one allele and a missense mutation in the other are the most severely affected. Because of nonsense-mediated decay, most hypomorphic alleles are not expressed, resulting in homozygous expression of the missense mutation allele. This should result in 50% reduced expression of the ryanodine receptor in skeletal muscle, but its observed content is even lower. To study in more detail the biochemistry and pathophysiology of recessive RYR1 myopathies, here we investigated a mouse model we recently generated by analyzing the effect of bi-allelic versus mono-allelic expression of the RyR1 p.A4329D mutation. Our results revealed that the expression of two alleles carrying the same mutation or of one allele with the mutation in combination with a hypomorphic allele does not result in functionally equal outcomes and impacts skeletal muscles differently. In particular, the bi-allelic RyR1 p.A4329D mutation caused a milder phenotype than its mono-allelic expression, leading to changes in the biochemical properties and physiological function only of slow-twitch muscles and largely sparing fast-twitch muscles. In summary, bi-allelic expression of the RyR1 p.A4329D mutation phenotypically differs from mono-allelic expression of this mutation in a compound heterozygous carrier., Competing Interests: Conflict of interest—The authors declare that they have no conflicts of interest with the contents of this article., (© 2020 Elbaz et al.)
- Published
- 2020
- Full Text
- View/download PDF
77. Correlation Between Apparent Diffusion Coefficient Value on MRI and Histopathologic WHO Grades of Neuroendocrine Tumors.
- Author
-
Mebis W, Snoeckx A, Corthouts B, El Addouli H, Nicolay S, Van Hoyweghen A, Spinhoven M, and de Beeck BO
- Abstract
Background: The correlation of diffusion-weighted MRI and tumor aggressiveness has been established for different tumor types, which leads to the question if it could also apply for neuroendocrine tumors (NET)., Purpose: To investigate the possible correlation between apparent diffusion coefficient (ADC) value on magnetic resonance imaging (MRI) and histopathologic WHO-grades of NET., Material and Methods: Electronic patient records from patients presented at the multidisciplinary neuro-endocrine tumor board between November 2017 and April 2019 were retrospectively reviewed. Patients with both available MR imaging (primary tumor or metastasis) and known WHO tumor grade were included (n = 47). Average and minimum ADC values (avgADC; minADC) were measured by drawing a freehand ROI excluding only the outermost border of the lesion. The largest axial size (primary tumor) or most clearly delineated lesion (metastasis) was used., Results: Forty seven patients met the inclusion criteria (mean age 59 ± 12 SD; 24F/23M). Twenty one patients (45%) were diagnosed with WHO G1 tumor, 17 seventeen with G2 (36%) and nine with G3 (19%) tumor. Twenty eight primary tumors and 19 metastases were measured. A significant difference was found between low-grade (G1+G2) and high-grade (G3) tumors (Mann-Whitney; avgADC: p < 0,001; minADC: p = 0,001). There was a moderate negative correlation between WHO-grade and avgADC/minADC (Spearman; avgADC: -0,606; 95% CI [-0,773; -0,384]; minADC: -0,581; 95% CI [-0.759; -0.353])., Conclusion: Our data show a significant difference in both average and minimum ADC values on MRI between low and high grade NET. A moderate negative correlation was found between histopathologic WHO grade and ADC value., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2020 The Author(s).)
- Published
- 2020
- Full Text
- View/download PDF
78. Lesion detection on a combined "All-in-One" window compared to conventional window settings in thoracic oncology chest CT examinations.
- Author
-
Snoeckx A, Vuylsteke P, Broeckx BJG, Carpentier K, Corthouts R, Luyckx EA, Nicolay S, Hoyweghen AV, Spinhoven MJ, Cant J, and Parizel PM
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Lung Neoplasms diagnostic imaging, Male, Middle Aged, Retrospective Studies, Thoracic Neoplasms diagnostic imaging, Tomography, X-Ray Computed
- Abstract
Purpose: The purpose of this study was to investigate if lesion detection using a single "All-in-One" (AIO) window was non-inferior to lesion detection on conventional window settings in thoracic oncology chest computed tomography (CT) examinations., Materials and Methods: In a retrospective study, 50 consecutive chest CT examinations of 50 patients (31 men, 19 women; mean age 64±10 [SD] years, range: 35-82 years) containing 417 lesions, were reviewed by 6 radiologists, subdivided into 2 groups of 3 radiologists each, with similar levels of expertise in each group (senior staff member, junior staff member and radiology resident). All examinations were reviewed in conventional or AIO window settings by one of the groups. A 'lesion' was defined as any abnormality seen on the chest CT examination, including both benign and malignant lesions, findings in chest and upper abdomen, and measurable and non-measurable disease. Lesions were listed as 'missed' when they were not seen by at least two out of three observers. F-tests were used to evaluate the significance of the variables of interest within a mixed model framework and kappa statistics to report interobserver agreement., Results: On a reader level, 54/417 lesions (12.9%) were not detected by the senior staff member reading the studies in conventional window settings and 45/417 (10.8%) by the senior staff member reading the AIO images. For the junior staff member and radiology resident this was respectively 55/417 (13.2%) and 67/417 (16.1%) for the conventional window settings and 43/417 (10.3%) and 61/417 (14.6%) for the AIO window. On a lesion level, 68/417 (16.3%) were defined as 'missed' lesions (lesions not detected by at least 2 readers): 21/68 (30.9%) on the AIO-window, 30/68 (44.1%) on conventional views and 17/68 (25.0%) on both views. The use of the AIO window did not result in an increase of missed lesions (P>0.99). Interobserver agreement in both groups was similar (P=0.46). Regarding lesions that were categorized as 'missed' on the AIO window or on conventional window settings, there was no effect of location (chest or upper abdomen) (P=0.35), window (P=0.97) and organ (P=0.98)., Conclusions: A single AIO-window is non-inferior to multiple conventional window settings for lesion detection on chest CT examinations in thoracic oncology patients., (Copyright © 2019 Société française de radiologie. Published by Elsevier Masson SAS. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
79. Lesion measurement on a combined "all-in-one" window for chest CT: effect on intra- and interobserver variability.
- Author
-
Snoeckx A, Cant J, Franck C, Luyckx E, Carpentier K, Nicolay S, Van Hoyweghen A, Spinhoven MJ, Vuylsteke P, and Parizel PM
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Image Processing, Computer-Assisted standards, Lung Neoplasms diagnostic imaging, Male, Middle Aged, Multidetector Computed Tomography standards, Observer Variation, Reproducibility of Results, Retrospective Studies, Abdomen diagnostic imaging, Image Processing, Computer-Assisted methods, Multidetector Computed Tomography methods, Neoplasms diagnostic imaging, Thorax diagnostic imaging
- Abstract
Purpose: A newly developed image processing technique fuses conventional windows into a single 'All-In-One' (AIO) window. This study aims to evaluate variability of CT measurement of lesions in thoracic oncology patients on this novel AIO-window., Methods: Six radiologists with different levels of expertise measured 368 lesions of various size, origin and sharpness. All lesions were measured twice on the AIO-window and twice on the conventional window settings. Intraclass correlation coefficients and Bland-Altman plots were used to assess intra- and interobserver variability., Results: Overall intra-observer agreement for lesion diameters on the AIO-window and conventional window settings was 0.986 (95% Confidence interval (CI): 0.983-0.989) and 0.991 (95% CI 0.989-0.993) respectively. For interobserver agreement this was 0.982 (95% CI 0.979-0.985) (AIO) and 0.979 (95% CI 0.957-0.982) (conventional). For both the AIO and conventional windows, intra- and interobserver agreement were dependent on size, sharpness and reader experience. Measurement variability decreased with increasing lesion size. Regarding sharpness, inter- and intra-observer agreement ranged from 0.986-0.989 (AIO) and 0.985-0.992 (conventional) for well-defined lesions and from 0.978-0.983 (AIO) and 0.974-0.991 (conventional) for ill-defined lesions., Conclusions: Lesion diameters were consistently smaller on the AIO-window compared to conventional window settings. Overall intra- and interobserver variability rates were similar for the AIO-window and conventional window settings. We conclude that the AIO-window offers a reliable and reproducible alternative for measurement of thoracic lesions.
- Published
- 2019
- Full Text
- View/download PDF
80. Diagnostic and clinical features of lung cancer associated with cystic airspaces.
- Author
-
Snoeckx A, Reyntiens P, Carp L, Spinhoven MJ, El Addouli H, Van Hoyweghen A, Nicolay S, Van Schil PE, Pauwels P, van Meerbeeck JP, and Parizel PM
- Abstract
"Lung cancer associated with cystic airspaces" is an uncommon manifestation, in which lung cancer presents on imaging studies with a cystic area with associated consolidation and/or ground glass. With the widespread use of computed tomography (CT), both in clinical practice and for lung cancer screening, these tumors are being more frequently recognized. An association of this entity with smoking has been established with the majority of cases reported being in former and current smokers. The true pathogenesis of the cystic airspace is not yet fully understood. Different causes of this cystic airspace have been described, including a check-valve mechanism obstructing the small airways, lepidic growth of adenocarcinoma on emphysematous lung parenchyma, cyst formation of tumor and tumor growth along the wall of a pre-existing bulla. Adenocarcinoma is the commonest histological type, followed by squamous cell carcinoma. Two classification systems have been described, based on morphological features of the lesion, taking into account both the cystic airspace as well as the morphology of the surrounding consolidation or ground glass. The cystic component may mislead radiologists to a benign etiology and the many different faces on imaging can make early diagnosis challenging. Special attention should be made to focal or diffuse wall thickening and consolidation or ground glass abutting or interspersed with cystic airspaces. Despite their atypical morphology, staging and management currently are still similar to that of other lung cancer types. Although the rarity of this entity will hamper larger studies, numerous aspects regarding this particular lung cancer type still need to be unraveled. This manuscript reviews the CT-imaging findings and gives an overview of available data in the English literature on pathogenesis, histopathology and clinical findings. Differential diagnosis and pitfalls are discussed as well as future directions regarding staging and management., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.
- Published
- 2019
- Full Text
- View/download PDF
81. Fully textured monolithic perovskite/silicon tandem solar cells with 25.2% power conversion efficiency.
- Author
-
Sahli F, Werner J, Kamino BA, Bräuninger M, Monnard R, Paviet-Salomon B, Barraud L, Ding L, Diaz Leon JJ, Sacchetto D, Cattaneo G, Despeisse M, Boccard M, Nicolay S, Jeangros Q, Niesen B, and Ballif C
- Abstract
Tandem devices combining perovskite and silicon solar cells are promising candidates to achieve power conversion efficiencies above 30% at reasonable costs. State-of-the-art monolithic two-terminal perovskite/silicon tandem devices have so far featured silicon bottom cells that are polished on their front side to be compatible with the perovskite fabrication process. This concession leads to higher potential production costs, higher reflection losses and non-ideal light trapping. To tackle this issue, we developed a top cell deposition process that achieves the conformal growth of multiple compounds with controlled optoelectronic properties directly on the micrometre-sized pyramids of textured monocrystalline silicon. Tandem devices featuring a silicon heterojunction cell and a nanocrystalline silicon recombination junction demonstrate a certified steady-state efficiency of 25.2%. Our optical design yields a current density of 19.5 mA cm
- 2 thanks to the silicon pyramidal texture and suggests a path for the realization of 30% monolithic perovskite/silicon tandem devices.- Published
- 2018
- Full Text
- View/download PDF
82. Neurocomplications of Recreational Drug Use.
- Author
-
van den Hauwe L, Huyskens J, Nicolay S, Van Goethem JW, and Parizel PM
- Published
- 2017
- Full Text
- View/download PDF
83. Extracting oscillating components from nonstationary time series: A wavelet-induced method.
- Author
-
Deliège A and Nicolay S
- Abstract
This paper consists in the description and application of a method called wavelet-induced mode extraction (WIME) in the context of time-frequency analysis. WIME aims to extract the oscillating components that build amplitude modulated-frequency modulated signals. The essence of this technique relies on the successive extractions of the dominant ridges of wavelet-based time-frequency representations of the signal under consideration. Our tests on simulated examples indicate strong decomposition and reconstruction skills, trouble-free handling of crossing trajectories in the time-frequency plane, sharp performances in frequency detection in the case of mode-mixing problems, and a natural tolerance to noise. These results are compared with those obtained with empirical mode decomposition. We also show that WIME still gives meaningful results with real-life data, namely, the Oceanic Niño Index.
- Published
- 2017
- Full Text
- View/download PDF
84. Direct Imaging of Dopant Distribution in Polycrystalline ZnO Films.
- Author
-
Lorenzo F, Aebersold AB, Morales-Masis M, Ledinský M, Escrig S, Vetushka A, Alexander DT, Hessler-Wyser A, Fejfar A, Hébert C, Nicolay S, and Ballif C
- Abstract
Two fundamental requirements of transparent conductive oxides are high conductivity and low optical absorptance, properties strongly dependent on the free-carrier concentration of the film. The free-carrier concentration is usually tuned by the addition of dopant atoms; which are commonly assumed to be uniformly distributed in the films or partially segregated at grain boundaries. Here, the combination of secondary ion mass spectroscopy at the nanometric scale (NanoSIMS) and Kelvin probe force microscopy (KPFM) allows direct imaging of boron-dopant distribution in polycrystalline zinc oxide (ZnO) films. This work demonstrates that the boron atoms have a bimodal spatial distribution within each grain of the ZnO films. NanoSIMS analysis shows that boron atoms are preferentially incorporated into one of the two sides of each ZnO grain. KPFM measurements confirm that boron atoms are electrically active, locally increasing the free-carrier concentration in the film. The proposed cause of this nonuniform dopant distribution is the different sticking coefficient of Zn adatoms on the two distinct surface terminations of the ZnO grains. The higher sticking coefficient of Zn on the c+ surface restricts the boron incorporation on this side of the grains, resulting in preferential boron incorporation on the c- side and causing the bimodal distribution.
- Published
- 2017
- Full Text
- View/download PDF
85. Parasitic Absorption Reduction in Metal Oxide-Based Transparent Electrodes: Application in Perovskite Solar Cells.
- Author
-
Werner J, Geissbühler J, Dabirian A, Nicolay S, Morales-Masis M, Wolf SD, Niesen B, and Ballif C
- Abstract
Transition metal oxides (TMOs) are commonly used in a wide spectrum of device applications, thanks to their interesting electronic, photochromic, and electrochromic properties. Their environmental sensitivity, exploited for gas and chemical sensors, is however undesirable for application in optoelectronic devices, where TMOs are used as charge injection or extraction layers. In this work, we first study the coloration of molybdenum and tungsten oxide layers, induced by thermal annealing, Ar plasma exposure, or transparent conducting oxide overlayer deposition, typically used in solar cell fabrication. We then propose a discoloration method based on an oxidizing CO2 plasma treatment, which allows for a complete bleaching of colored TMO films and prevents any subsequent recoloration during following cell processing steps. Then, we show that tungsten oxide is intrinsically more resilient to damage induced by Ar plasma exposure as compared to the commonly used molybdenum oxide. Finally, we show that parasitic absorption in TMO-based transparent electrodes, as used for semitransparent perovskite solar cells, silicon heterojunction solar cells, or perovskite/silicon tandem solar cells, can be drastically reduced by replacing molybdenum oxide with tungsten oxide and by applying a CO2 plasma pretreatment prior to the transparent conductive oxide overlayer deposition.
- Published
- 2016
- Full Text
- View/download PDF
86. CT imaging features of atrioventricular shunts: what the radiologist must know.
- Author
-
Nicolay S, Salgado RA, Shivalkar B, Van Herck PL, Vrints C, and Parizel PM
- Abstract
Unlabelled: In the last decade, cardiac computed tomography (CT) has gained mainstream acceptance for the noninvasive exclusion of significant coronary disease in a selected population. Improvements in electrocardiogram (ECG)-triggered imaging techniques also allow, by extension, a proper evaluation of the complete heart anatomy. Given the increasing worldwide clinical implementation of cardiac CT for coronary artery evaluation, radiologists can, incidentally, be confronted with unfamiliar and previously unsuspected non-coronary cardiac pathologies, including congenital morphological defects. This presence of congenital heart disease (CHD) should not be overlooked, being the most common form of birth defect, with a total birth prevalence of 9.1 per 1000 live births worldwide [1]. The prevalence of adult patients with CHD is estimated to be 3000 per million adults [2]. Ventricular septal defects (VSDs) are the most frequent subtypes of CHD, accounting together with atrial septal defects (ASDs) for nearly half of all CHD cases [1]. While some small defects are rarely symptomatic and can go undetected for life, others are clinically significant and require adequate and timely medical intervention. In this article, we present the CT imaging features of atrioventricular (AV) shunts, highlighting both their embryological origins and associated relevant clinical features., Teaching Points: • Congenital heart disease (CHD) is the most common birth defect. • Ventricular and atrial septal defects account for nearly half of CHD cases. • Atrioventricular defects can frequently be detected on a cardiac CT. • Radiologists must be able to identify clinically significant atrioventricular defects.
- Published
- 2016
- Full Text
- View/download PDF
87. The Endovascular Treatment of Epistaxis.
- Author
-
Nicolay S, Van Der Zijden T, Voormolen M, d'Archambeau O, Maes J, De Belder F, and Parizel PM
- Abstract
Epistaxis or nosebleed is relatively common in the general population. Depending on the location of the bleeding in the nasal cavity, epistaxis can be divided in two types: anterior or posterior type. The anterior type is far more frequent, often self-limiting and, if needed, is relatively easy treatable. Posterior type epistaxis is rare and more likely to require medical attention. The cornerstone of the conservative therapy of posterior epistaxis is nasal packing. Only in patients with persistent or recurrent epistaxis, endovascular intervention or surgery is indicated. Both treatment options have a similar success and complication rate, but endovascular treatment, if feasible, has several advantages above surgical treatment. The choice of procedure should be made on a patient-to-patient basis, taking several parameters into account. In this pictorial essay we present an overview of the relevant radiological anatomy and a review of various causes of epistaxis, with the emphasis on the endovascular treatment.
- Published
- 2015
- Full Text
- View/download PDF
88. Effect of the thin-film limit on the measurable optical properties of graphene.
- Author
-
Holovský J, Nicolay S, De Wolf S, and Ballif C
- Abstract
The fundamental sheet conductance of graphene can be directly related to the product of its absorption coefficient, thickness and refractive index. The same can be done for graphene's fundamental opacity if the so-called thin-film limit is considered. Here, we test mathematically and experimentally the validity of this limit on graphene, as well as on thin metal and semiconductor layers. Notably, within this limit, all measurable properties depend only on the product of the absorption coefficient, thickness, and refractive index. As a direct consequence, the absorptance of graphene depends on the refractive indices of the surrounding media. This explains the difficulty in determining separately the optical constants of graphene and their widely varying values found in literature so far. Finally, our results allow an accurate estimation of the potential optical losses or gains when graphene is used for various optoelectronic applications.
- Published
- 2015
- Full Text
- View/download PDF
89. Organic-inorganic halide perovskite/crystalline silicon four-terminal tandem solar cells.
- Author
-
Löper P, Moon SJ, de Nicolas SM, Niesen B, Ledinsky M, Nicolay S, Bailat J, Yum JH, De Wolf S, and Ballif C
- Abstract
Tandem solar cells constructed from a crystalline silicon (c-Si) bottom cell and a low-cost top cell offer a promising way to ensure long-term price reductions of photovoltaic modules. We present a four-terminal tandem solar cell consisting of a methyl ammonium lead triiodide (CH3NH3PbI3) top cell and a c-Si heterojunction bottom cell. The CH3NH3PbI3 top cell exhibits broad-band transparency owing to its design free of metallic components and yields a transmittance of >55% in the near-infrared spectral region. This allows the generation of a short-circuit current density of 13.7 mA cm(-2) in the bottom cell. The four-terminal tandem solar cell yields an efficiency of 13.4% (top cell: 6.2%, bottom cell: 7.2%), which is a gain of 1.8%abs with respect to the reference single-junction CH3NH3PbI3 solar cell with metal back contact. We employ the four-terminal tandem solar cell for a detailed investigation of the optical losses and to derive guidelines for further efficiency improvements. Based on a power loss analysis, we estimate that tandem efficiencies of ∼28% are attainable using an optically optimized system based on current technology, whereas a fully optimized, ultimate device with matched current could yield up to 31.6%.
- Published
- 2015
- Full Text
- View/download PDF
90. Aberrant internal carotid artery presenting as a retrotympanic vascular mass.
- Author
-
Nicolay S, De Foer B, Bernaerts A, Van Dinther J, and Parizel PM
- Abstract
We report a case of a young woman with an aberrant right internal carotid artery (ICA) presenting as a retrotympanic reddish mass. This variant of the ICA represents the collateral pathway that is formed as a result of an embryological agenesis of the cervical segment of the ICA. The embryonic inferior tympanic artery is recruited to bypass the absent carotid segment. This hypertrophied vessel may be seen otoscopically and wrongfully considered to be a vascular middle ear tumor. Informing the otorhinolaryngologist of this important vascular variant not only obviates biopsy but also helps in careful preoperative planning of eventual middle ear procedures.
- Published
- 2014
- Full Text
- View/download PDF
91. A case of a temporal bone meningioma presenting as a serous otitis media.
- Author
-
Nicolay S, De Foer B, Bernaerts A, Van Dinther J, and Parizel PM
- Abstract
We report the imaging features of a case of a temporal bone meningioma extending into the middle ear cavity and clinically presenting as a serous otitis media. Temporal bone meningioma extending in the mastoid or the middle ear cavity, however, is very rare. In case of unexplained or therapy-resistant serous otitis media and a nasopharyngeal tumor being ruled out, a temporal bone computed tomography (CT) should be performed. If CT findings are suggestive of a temporal bone meningioma, a magnetic resonance imaging (MRI) examination with gadolinium will confirm diagnosis and show the exact extension of the lesion.
- Published
- 2014
- Full Text
- View/download PDF
92. Atraumatic bilateral scapular spine fracture several months after bilateral reverse total shoulder arthroplasty.
- Author
-
Nicolay S, De Beuckeleer L, Stoffelen D, Vanhoenacker F, and Pouillon M
- Subjects
- Aged, 80 and over, Female, Fractures, Bone rehabilitation, Humans, Radiography, Radionuclide Imaging, Scapula diagnostic imaging, Shoulder Joint diagnostic imaging, Shoulder Pain diagnosis, Arthroplasty, Replacement adverse effects, Fractures, Bone diagnosis, Fractures, Bone etiology, Scapula injuries, Shoulder Joint surgery, Shoulder Pain etiology
- Abstract
We report an 89-year-old woman with bilateral atraumatic scapular spine fracture several months after bilateral reverse total shoulder arthroplasty (RTSA). Recently, RTSA has gained popularity in the surgical treatment of complex shoulder disorders such as cuff tear arthropathy. However, scapular fractures may occur several months after surgery as a late complication of this procedure. In this case report we focus on a relatively uncommon subtype, the scapular spine fracture. Although well-known in the orthopedic literature, radiologists are less familiar with this complication. To the best of our knowledge, bilateral scapular fractures have not yet been reported.
- Published
- 2014
- Full Text
- View/download PDF
93. Epidermal inclusion cyst of the perianal region.
- Author
-
Nicolay S, De Schepper A, and Pouillon M
- Subjects
- Anal Canal diagnostic imaging, Anal Canal pathology, Diagnosis, Differential, Humans, Magnetic Resonance Imaging methods, Male, Middle Aged, Ultrasonography methods, Anus Diseases diagnostic imaging, Anus Diseases pathology, Epidermal Cyst diagnostic imaging, Epidermal Cyst pathology
- Published
- 2014
- Full Text
- View/download PDF
94. Analysis of PSII antenna size heterogeneity of Chlamydomonas reinhardtii during state transitions.
- Author
-
de Marchin T, Ghysels B, Nicolay S, and Franck F
- Subjects
- Chlamydomonas reinhardtii chemistry, Chlorophyll metabolism, Fluorescence, Kinetics, Light, Phosphorylation, Photosystem II Protein Complex metabolism, Thylakoids metabolism, Chlamydomonas reinhardtii physiology, Chlorophyll chemistry, Photosystem II Protein Complex chemistry, Thylakoids chemistry
- Abstract
PSII antenna size heterogeneity has been intensively studied in the past. Based on DCMU fluorescence rise kinetics, multiple types of photosystems with different properties were described. However, due to the complexity of fluorescence signal analysis, multiple questions remain unanswered. The number of different types of PSII is still debated as well as their degree of connectivity. In Chlamydomonas reinhardtii we found that PSIIα possesses a high degree of connectivity and an antenna 2-3 times larger than PSIIβ, as described previously. We also found some connectivity for PSIIβ in contrast with the majority of previous studies. This is in agreement with biochemical studies which describe PSII mega-, super- and core-complexes in Chlamydomonas. In these studies, the smallest unit of PSII in vivo would be a dimer of two core complexes hence allowing connectivity. We discuss the possible relationships between PSIIα and PSIIβ and the PSII mega-, super- and core-complexes. We also showed that strain and medium dependent variations in the half-time of the fluorescence rise can be explained by variations in the proportions of PSIIα and PSIIβ. When analyzing the state transition process in vivo, we found that this process induces an inter-conversion of PSIIα and PSIIβ. During a transition from state 2 to state 1, DCMU fluorescence rise kinetics are satisfactorily fitted by considering two PSII populations with constant kinetic parameters. We discuss our findings about PSII heterogeneity during state transitions in relation with recent results on the remodeling of the pigment-protein PSII architecture during this process., (© 2013.)
- Published
- 2014
- Full Text
- View/download PDF
95. Multiscale transparent electrode architecture for efficient light management and carrier collection in solar cells.
- Author
-
Boccard M, Battaglia C, Hänni S, Söderström K, Escarré J, Nicolay S, Meillaud F, Despeisse M, and Ballif C
- Subjects
- Equipment Design, Equipment Failure Analysis, Light, Particle Size, Refractometry, Scattering, Radiation, Electric Power Supplies, Electrodes, Nanostructures chemistry, Nanostructures ultrastructure, Nanotechnology instrumentation, Solar Energy
- Abstract
The challenge for all photovoltaic technologies is to maximize light absorption, to convert photons with minimal losses into electric charges, and to efficiently extract them to the electrical circuit. For thin-film solar cells, all these tasks rely heavily on the transparent front electrode. Here we present a multiscale electrode architecture that allows us to achieve efficiencies as high as 14.1% with a thin-film silicon tandem solar cell employing only 3 μm of silicon. Our approach combines the versatility of nanoimprint lithography, the unusually high carrier mobility of hydrogenated indium oxide (over 100 cm(2)/V/s), and the unequaled light-scattering properties of self-textured zinc oxide. A multiscale texture provides light trapping over a broad wavelength range while ensuring an optimum morphology for the growth of high-quality silicon layers. A conductive bilayer stack guarantees carrier extraction while minimizing parasitic absorption losses. The tunability accessible through such multiscale electrode architecture offers unprecedented possibilities to address the trade-off between cell optical and electrical performance., (© 2012 American Chemical Society)
- Published
- 2012
- Full Text
- View/download PDF
96. DNA replication timing data corroborate in silico human replication origin predictions.
- Author
-
Audit B, Nicolay S, Huvet M, Touchon M, d'Aubenton-Carafa Y, Thermes C, and Arneodo A
- Subjects
- Animals, Humans, DNA Replication, Genome, Human, Models, Genetic, Pattern Recognition, Automated methods
- Abstract
We develop a wavelet-based multiscale pattern recognition methodology to disentangle the replication- from the transcription-associated compositional strand asymmetries observed in the human genome. Comparing replication skew profiles to recent high-resolution replication timing data reveals that most of the putative replication origins that border the so-identified replication domains are replicated earlier than their surroundings whereas the central regions replicate late in the S phase. We discuss the implications of this first experimental confirmation of these replication origin predictions that are likely to be early replicating and active in most tissues.
- Published
- 2007
- Full Text
- View/download PDF
97. Human gene organization driven by the coordination of replication and transcription.
- Author
-
Huvet M, Nicolay S, Touchon M, Audit B, d'Aubenton-Carafa Y, Arneodo A, and Thermes C
- Subjects
- Base Sequence, Chromatin chemistry, DNA, Intergenic, Gene Duplication, Gene Order, Humans, Models, Genetic, Replication Origin, S Phase, DNA Replication, Genes, Transcription, Genetic
- Abstract
In this work, we investigated a large-scale organization of the human genes with respect to putative replication origins. We developed an appropriate multiscale method to analyze the nucleotide compositional skew along the genome and found that in more than one-quarter of the genome, the skew profile presents characteristic patterns consisting of successions of N-shaped structures, designated here N-domains, bordered by putative replication origins. Our analysis of recent experimental timing data confirmed that, in a number of cases, domain borders coincide with replication initiation zones active in the early S phase, whereas the central regions replicate in the late S phase. Around the putative origins, genes are abundant and broadly expressed, and their transcription is co-oriented with replication fork progression. These features weaken progressively with the distance from putative replication origins. At the center of domains, genes are rare and expressed in few tissues. We propose that this specific organization could result from the constraints of accommodating the replication and transcription initiation processes at chromatin level, and reducing head-on collisions between the two machineries. Our findings provide a new model of gene organization in the human genome, which integrates transcription, replication, and chromatin structure as coordinated determinants of genome architecture.
- Published
- 2007
- Full Text
- View/download PDF
98. Bifractality of human DNA strand-asymmetry profiles results from transcription.
- Author
-
Nicolay S, Brodie Of Brodie EB, Touchon M, Audit B, d'Aubenton-Carafa Y, Thermes C, and Arneodo A
- Subjects
- Base Sequence, Humans, Molecular Sequence Data, Chromosome Mapping methods, DNA chemistry, DNA genetics, Fractals, Sequence Analysis, DNA methods, Transcription, Genetic genetics
- Abstract
We use the wavelet transform modulus maxima method to investigate the multifractal properties of strand-asymmetry DNA walk profiles in the human genome. This study reveals the bifractal nature of these profiles, which involve two competing scale-invariant (up to repeat-masked distances less, or similar 40 kbp) components characterized by Hölder exponents h{1}=0.78 and h{2}=1, respectively. The former corresponds to the long-range-correlated homogeneous fluctuations previously observed in DNA walks generated with structural codings. The latter is associated with the presence of jumps in the original strand-asymmetry noisy signal S. We show that a majority of upward (downward) jumps co-locate with gene transcription start (end) sites. Here 7228 human gene transcription start sites from the refGene database are found within 2 kbp from an upward jump of amplitude DeltaS > or = 0.1 which suggests that about 36% of annotated human genes present significant transcription-induced strand asymmetry and very likely high expression rate.
- Published
- 2007
- Full Text
- View/download PDF
99. Functional modes of proteins are among the most robust.
- Author
-
Nicolay S and Sanejouand YH
- Subjects
- Computational Biology, Computer Simulation, Protein Structure, Tertiary, Data Interpretation, Statistical, Protein Conformation, Proteins chemistry
- Abstract
It is shown that a small subset of modes which are likely to be involved in protein functional motions of large amplitude can be determined by retaining the most robust normal modes obtained using different protein models. This result should prove helpful in the context of several applications proposed recently, like for solving difficult molecular replacement problems or for fitting atomic structures into low-resolution electron density maps. It may also pave the way for the development of methods allowing us to predict such motions accurately.
- Published
- 2006
- Full Text
- View/download PDF
100. Replication-associated strand asymmetries in mammalian genomes: toward detection of replication origins.
- Author
-
Touchon M, Nicolay S, Audit B, Brodie of Brodie EB, d'Aubenton-Carafa Y, Arneodo A, and Thermes C
- Subjects
- Animals, Base Composition, Base Sequence, Computational Biology methods, Genomics methods, Humans, Sequence Alignment, DNA genetics, DNA Replication genetics, Dogs genetics, Evolution, Molecular, Genome, Human, Mice genetics, Replication Origin genetics
- Abstract
In the course of evolution, mutations do not affect both strands of genomic DNA equally. This imbalance mainly results from asymmetric DNA mutation and repair processes associated with replication and transcription. In prokaryotes, prevalence of G over C and T over A is frequently observed in the leading strand. The sign of the resulting TA and GC skews changes abruptly when crossing replication-origin and termination sites, producing characteristic step-like transitions. In mammals, transcription-coupled skews have been detected, but so far, no bias has been associated with replication. Here, analysis of intergenic and transcribed regions flanking experimentally identified human replication origins and the corresponding mouse and dog homologous regions demonstrates the existence of compositional strand asymmetries associated with replication. Multiscale analysis of human genome skew profiles reveals numerous transitions that allow us to identify a set of 1,000 putative replication initiation zones. Around these putative origins, the skew profile displays a characteristic jagged pattern also observed in mouse and dog genomes. We therefore propose that in mammalian cells, replication termination sites are randomly distributed between adjacent origins. Taken together, these analyses constitute a step toward genome-wide studies of replication mechanisms.
- Published
- 2005
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.