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With the rapidly advancing perovskite solar cell (PSC) technology, dedicated interface engineering is critical for improving device stability. Atomic layer deposition (ALD) grown metal oxide films have drawn immense attention for the fabrication of stable PSC. Despite the advantages of ALD, the deposition of metal oxides directly on bare perovskite has so far not been achieved without damaging the perovskite layer underneath. In addition, the changes to the physicochemical and electronic properties at the perovskite interface upon exposure to the ALD precursors can alter the material and hence device functionality. Herein, we report on a synchrotron-based hard X-ray photoelectron spectroscopy (HAXPES) investigation of the interface between metal halide perovskite (MHP) absorber and ALD-SnO 2 electron transport layer. We find clear evidence for the formation of new chemical species (nitrogen compound, lead dihalides) and an upward band bending in the MHP and downward band bending in the SnO 2 towards the MHP/ALD-SnO 2 interface. The upward bending at the interface forms an electron barrier layer of ∼400 meV, which is detrimental to the PSC performance. In addition, we assess the effectiveness of introducing a thin interlayer of the organic electron transport material Phenyl-C61-butyric acid methyl ester (PCBM) between MHP and ALD-SnO 2 to mitigate the effects of ALD deposition. [Display omitted] • Direct probe of the chemical and electronic properties at the buried halide perovskite/ ALD-SnO 2 layers by HAXPES. • Interfacial defects from degraded formamidinium due to chemical reactions between perovskite and ALD precursors. • Suggested band bending at the perovskite/ALD-SnO 2 interface, resulting in an electron barrier detrimental to device operation. • Use of PCBM interlayer between perovskite and SnO 2 partly mitigates the chemical reactions. [ABSTRACT FROM AUTHOR]

Using density functional theory (DFT) calculations and angle-resolved photoemission spectroscopy (ARPES) the structural and electronic properties of graphene on the surface and subsurface Co–Ir alloy are investigated upon the intercalation of Co in graphene/Ir(111). It is found computationally that the interaction strength between graphene and substrate is strongly affected by the composition and nature of an alloy, implying the large difference in the electronic structure of monolayer graphene on Co x Ir 1− x /Ir(111) and Ir/Co x Ir 1− x /Ir(111). Our theoretical results are supported by ARPES data, which demonstrate the disappearance of the Dirac cone when graphene lies on Co and its restoration upon the formation of the subsurface Co–Ir alloy. [Display omitted] • The composition and position of CoIr alloy affects the graphene layer morphology. • The presence of Co at the interface tends to destroy the Dirac cone. • The Dirac cone is preserved if subsurface Co–Ir alloy is formed. [ABSTRACT FROM AUTHOR]

Thoracic endometriosis is defined as the ectopic presence of endometrial glands and stroma in lung or pleura and constitutes an uncommon cause of spontaneous pneumothorax in nonsmoker women in childbearing age. From 2000 to 2014, 18 (7.3%) women of 246 had a histologically proven endometriosis-related pneumothorax. The examination of thoracic samples was performed on formalin-fixed, paraffin-embedded hematoxylin and eosin–stained slides. Immunohistochemistry was carried out on all samples. The pathologic findings included endometriosis foci appearing as a triad of endometrial glands, stroma, and hemosiderin-laden macrophages in 8 patients. In the remaining 10 patients, minute nests of endometrial stroma were recognized at histologic examination and immunohistochemistry. One patient displayed diaphragmatic endometriosis and pulmonary lymphangioleiomyomatosis. Thoracic endometriosis is an uncommon cause of recurrent pneumothorax necessitating histologic confirmation. The histologic diagnosis of endometriosis may be challenging on small pleural or lung biopsies because endometriosis mostly appears as minute nests of endometrial stromal cells. Here, we present our experience on thoracic endometriosis: considering frequent interpretation difficulties of biopsy samples, we propose a multidisciplinary diagnostic algorithm. [ABSTRACT FROM AUTHOR]

Highlights: [•] Coiled coils are abundant domains important for protein–protein oligomerisation. [•] Prediction of their oligomer states remains challenging. [•] We tested the algorithm, LOGICOIL, on coiled-coils from tenascins and thrombospondins. [•] LOGICOIL outperforms current widely used algorithms. [•] Conserved features of trimerising and pentamerising coiled-coils were identified. [Copyright &y& Elsevier]

Abstract: This paper presents an experimental investigation on the effect of concrete compressive strength and confinement method on confined high and ultra high-strength concrete (HSC and UHSC) specimens. A total of 55 fiber reinforced polymer (FRP) confined concrete specimens were tested under monotonic axial compression. All specimens were cylinders with 152mm diameter and 305mm height and confined by carbon FRP (CFRP). Three different concrete mixes were examined, with average compressive strengths of 35, 65 and 100MPa. The effect of the confinement method was also examined with FRP-wrapped specimens compared to FRP tube-encased specimens. Axial and lateral behavior was recorded to observe the axial stress–strain relationship and lateral strain behavior for concentric compression. Ultimate axial and lateral conditions are tabulated and the complete stress–strain curves have been provided. The experimental results presented in this paper provide a performance comparison between FRP-confined conventional normal-strength concrete (NSC) and the lesser understood area of FRP-confined HSC and UHSC. The results of this experimental study clearly indicate that above a certain confinement threshold, FRP-confined HSC and UHSC exhibits highly ductile behavior, however for the same normalized confinement pressures, axial performance of FRP-confined concrete reduces as concrete strength increases. The results also indicate that ultimate conditions of FRP-wrapped specimens are similar to those confined by FRP tubes, however a performance difference is evident at the transition region. The performance of 10 existing stress–strain models were assessed against the experimental datasets and the performance of these models discussed. The results of this model assessment revealed the need for further development for stress–strain models developed specifically for FRP-confined HSC or UHSC. [Copyright &y& Elsevier]

Recently, with the aim of decreasing the environmental impact of concrete, developing an environmentally friendly construction material using industrial by-products has received great attention. This study aims for developing an eco-friendly construction material using industrial by-products as alternatives to cement, namely fly ash (FA) and ground granulated blast furnace slag (GGBS), and green nanoparticles (un-calcined high- (HH) and low-halloysite kaolin (LH)). 12 batches of cement-based and geopolymer mortars were manufactured, and their setting time, efflorescence, and compressive and splitting tensile strength were evaluated. Scanning electron microscopy (SEM) was performed to characterize the microstructure of the mortars. Production cost and embodied CO 2 of the mortars were also investigated. The results reveal that increasing kaolin content increases the setting time of the geopolymer, with mortars containing LH having a higher setting time than those containing HH. Incorporating HH leads to an increase (up to 6% at 6% HH) in the compressive strength of geopolymer, whereas incorporating LH results in a decrease (up to 6% at 9% LH) in the compressive strength of geopolymer. The results also show that both geopolymers containing HH and LH exhibit a higher splitting tensile strength (30–32% and 11–18%, respectively) than that of the companion geopolymers with no kaolin. Although the production cost of geopolymers is currently higher (∼40%) than that of the cement-based mortars, it is shown that their embodied CO 2 is significantly lower (∼134%), even when un-calcined kaolin is used in the geopolymer. These findings are promising and indicate the significant potential of using un-calcined kaolin materials in geopolymers towards cleaner production of structural grade construction materials. • Low- (LH) and high-halloysite kaolin (HH) were added to waste-based geopolymers. • Mechanical, microstructure, cost and embodied CO 2 of geopolymers were studied. • Setting time of geopolymers increases with increased kaolin content. • Adding HH causes an increase in compressive and tensile strength of geopolymers. • Geopolymer even with un-calcined kaolin has less embodied CO 2 than conventional mortar. [ABSTRACT FROM AUTHOR]

Highlights • First design-oriented model to acurately predict complete stress-strain curve of FRP-confined normal- and high-strength concrete. • Model predicts compressive strength of FRP-confined concrete more accurately than existing models. • Ultimate axial strain is determined using readily available input data with accuracy comparable to that of best performing existing models. • Simple and accurate expressions are proposed to predict axial stress and strain at the transition point. Abstract This study presents a simple yet powerful design-oriented model that makes use of commonly available input data to predict the axial stress–strain behavior of fiber reinforced polymer (FRP)-confined concrete in circular sections. The approach of identifying the most influential parameters on the axial compressive behavior of FRP-confined concrete and developing new expressions based on these parameters by balancing accuracy and simplicity of use was adopted. A comprehensive experimental test database of FRP-confined normal-strength and high-strength concrete (NSC and HSC) was compiled and used in the model development. Although the proposed expressions to predict the axial stress and strain at the ultimate and transition point of the stress-strain curve were simple, the results show that they performed as good as or better than the best performing existing models. Based on these expressions a model to predict the complete axial stress-strain curve of FRP-confined concrete was developed and verified against the available experimental data. The proposed model is applicable to both FRP-confined NSC and HSC with compressive strengths up to 120 MPa, and is the first accurate design-oriented model to provide the complete stress-strain curve of FRP-confined HSC. [ABSTRACT FROM AUTHOR]

Abstract: An important application of FRP composites is as a confining material for concrete, in both the seismic retrofit of existing reinforced concrete columns and in the construction of concrete-filled FRP tubes as earthquake-resistant columns in new construction. Reliable design of these structural members necessitates clear understanding and accurate modeling of the stress–strain behavior of FRP-confined concrete. To that end, a great number of studies have been conducted in the past two decades, which has led to the development of a large number of models to predict the stress–strain behavior of FRP-confined concrete under axial compression. This paper presents a comprehensive review of 88 models developed to predict the axial stress–strain behavior of FRP-confined concrete in circular sections. Each of the reviewed models and their theoretical bases are summarized and the models are classified into two broad categories, namely design-oriented and analysis-oriented models. This review summarizes the current published literature until the end of 2011, and presents a unified framework for future reference. To provide a comprehensive assessment of the performances of the reviewed models, a large and reliable test database containing the test results of 730 FRP-confined concrete cylinders tested under monotonic axial compression is first established. The performance of each existing stress–strain model is then assessed using this database, and the results of this assessment are presented through selected statistical indicators. In the final part of the paper, a critical discussion is presented on the important factors that influenced the overall performances of the models. A close examination of results of the model assessment has led to a number of important conclusions on the strengths and weaknesses of the existing stress–strain models, which are clearly summarized. Based on these observations, a number of recommendations regarding future research directions are also outlined. [Copyright &y& Elsevier]

The application of antisense technology to study physiological and disease processes continues to mature. Antisense approaches are among the most direct means to use genomic sequence information. When developing therapeutics, applications range from early target validation in discovery to the therapeutic product. In this review, we describe the application of antisense oligonucleotides (ASOs) to identify genes that are important in controlling angiogenesis. High-throughput assays in vitro have been used to evaluate many gene targets. Genes that appear to be important in angiogenesis are then evaluated further in animal models of ocular angiogenesis. The ability of ASOs to reduce target-gene expression in the appropriate cells in the eye raises the possibility that this class of compounds could be used for target validation in vivo, and also be developed as a novel class of therapeutics in their own right. [Copyright &y& Elsevier]

• First systematic review to compare cognitive to exercise interventions for brain health in aging. • Cognitive training improves brain microstructural outcomes, measured with DWI. • Exercise training improve brain macrostructural outcomes, like grey or white matter. • Both trainings modulated BOLD signal changes during cognitive tasks. • Much heterogeneity in literature yet interventions show promise to enhance cognition. Aging is associated with cognitive decline. Importantly cognition and cerebral health is enhanced with interventions like cognitive (CT) and exercise training (ET). However, effects of CT and ET interventions on brain magnetic resonance imaging outcomes have never been compared systematically. Here, the primary objective was to critically and systematically compare CT to ET in healthy older adults on brain MRI outcomes. A total of 38 studies were included in the final review. Although results were mixed, patterns were identified: CT showed improvements in white matter microstructure, while ET demonstrated macrostructural enhancements, and both demonstrated changes to task-based BOLD signal changes. Importantly, beneficial effects for cognitive and cerebral outcomes were observed by almost all, regardless of intervention type. Overall, it is suggested that future work include more than one MRI outcome, and report all results including null. To better understand the MRI changes associated with CT or ET, more studies explicitly comparing interventions within the same domain (i.e. resistance vs. aerobic) and between domains (i.e. CT vs. ET) are needed. [ABSTRACT FROM AUTHOR]

This study presents the results of the first experimental research on the axial compressive behavior of ultra-high-strength steel (UHSS) fiber reinforced concrete-filled FRP tubes (UHSSFR-CFFT). 24 circular UHSSFR-CFFT specimens were prepared and tested under axial compression to study the influence of unconfined concrete strength and fiber type. CFFTs were manufactured with glass, carbon and basalt reinforced polymer (GFRP, CFRP and BFRP) tubes with concrete compressive strengths (f′ co) ranging from 35 to 105 MPa. Axial and lateral behavior were examined closely, including variation of lateral behavior along height of specimen. The results showed that the influence of concrete compressive strength on axial compressive behavior of UHSSFR-CFFTs is dependent on fiber type. For a similar normalized lateral confining pressure of FRP jacket at ultimate (f lu / f′ co), axial stress enhancement ratios (k 1) were observed to decrease with an increase in f′ co for all three fiber types. On the other hand, the obtained axial strain enhancement ratios (k 2) indicated that k 2 is influenced more by f lu / f′ co than f′ co. Comparison of the recorded values of k 1 and k 2 for UHSSFR-CFFT with FRP-confined plain concrete showed similar trends on the influence of (f′ co) on k 1 , but an opposite trend was observed for k 2 of BFRP-confined specimens of the current study, in which k 2 increased with increasing f′ co. The results showed that the shape of the lateral strain-to-axial strain curves for UHSSFR CFRP- and BFRP-confined concrete specimens were similar to those of FRP-confined plain concrete, and this relationship was not influenced noticeably by f′ co. Conversely, the obtained shape of the lateral strain-to-axial strain curves for UHSSFR GFRP-confined specimens was noticeably different when compared to FRP-confined plain concrete, with this behavior influenced by f′ co. Finally, the results indicated that the addition of UHSS fibers in CFRP-confined specimens did not alter the influence of f′ co on strain reduction factor (k ɛ) where a decrease was observed by increasing f′ co. However, the converse outcome was observed for GFRP- and BFRP-confined specimens where an increase in k ɛ was observed when increasing f′ co. [ABSTRACT FROM AUTHOR]

• The effect of the length-to-thickness ratio is significant on the masonry strength. • Current correction factors of the masonry codes overestimate the strength of prisms. • Micro-modeling method is used simulate the behavior of masonry prisms. • New correction factors are proposed to account for the length-to-thickness ratio. The compressive strength of concrete masonry depends on the dimensions of the test prisms. The available international masonry codes apply correction factors based on the height-to-thickness ratio to modify the strength obtained from different sizes of prisms. In this study, finite element models were developed to investigate the accuracy of this approach. Simplified micro-modeling method was used to simulate the behavior of masonry prisms which was verified against experimental results. A parametric study was then performed to examine the effect of key parameters on the compressive strength of masonry. The effect of the length-to-thickness ratio of masonry prisms was found to be significant on the compressive strength and should be considered together with the well understood effect of height-to-thickness ratio to calculate the correction factors. It was also shown that the current correction factors provided in the masonry codes lead to overestimating the strength of masonry prisms. New correction factors have been proposed accounting both the height-to-thickness and length-to-thickness ratio to reliably and safely estimate the compressive strength of masonry prisms. [ABSTRACT FROM AUTHOR]

This paper presents a detailed study on the development of axial, lateral and Von Mises strains measured by contact and non-contact methods under axial compression fiber reinforced polymer (FRP) confined and unconfined concrete specimens. The focus of the study was on the correlation between macro responses and localized deformations and the effects of FRP confinement on the localization of deformations. A total of 10 specimens were experimentally tested with a range of instrumentation to measure different types of strain. Digital image correlation (DIC) was used to obtain full-field strain evolution during compressive loading of concrete specimens confined with various fiber reinforced polymers. The effect of confinement material on the compressive behavior and strain distribution of FRP-confined concrete was investigated. The evolution of axial, lateral and Von Mises strains were recorded and examined during axial loading, including post-peak strain softening behavior. Data recorded by the typical contact method of linear variable displacement transformers (LVDTs) and strain gauges were used to validate the non-contact DIC method. The results obtained from DIC data in this study showed that expansion of shear zone for unconfined concrete is more localized than FRP-confined specimens. The results also show that specimens confined with CFRP induced homogenous compressive behavior, whereas GFRP and BFRP specimens with lower lateral stiffness displayed local strain concentration and less homogenous response. It was also observed that DIC provides a more accurate estimation of the ultimate condition compared to the contact methods due to the ability of DIC to capture the evolution of full-field strains. [ABSTRACT FROM AUTHOR]

Highlights • Experimental study on concrete columns strengthened with fiber reinforced concrete jacket. • Using high-strength polyethylene fiber for column jacketing. • Interaction of fiber and steel reinforcement in the retrofitting jacket. • Effect of fiber ratio and steel reinforcement ratio on the behavior of retrofitted columns. • Axial force enhancement ratio and axial strain enhancement ratio of the retrofitted columns. Abstract This paper presents an experimental study on the axial compressive behavior of concrete columns retrofitted and confined by fiber-reinforced concrete (FRC) jackets. Three different engineered cementitious composite (ECC) mixes containing high-strength polyethylene fibers at three fiber volume fractions of 0%, 1%, and 2%, and one ultra-high performance cementitious composite (UHP) mix at fiber volume fraction of 4%, were prepared to produce FRC jackets around the core concrete. Horizontal stirrups were used in the FRC jackets with three different horizontal reinforcement ratios to investigate the effect of the level of confinement and the interaction between the conventional reinforcement and fibers. The results show that specimens having no fiber or stirrup in their retrofitting jacket exhibit a brittle behavior and only those containing both stirrup and fiber provide a ductile behavior. It was also observed that the lateral strain of the jacket layer at a given axial strain increased with an increase in the fiber content, indicating an increased rate of dilation for the jacket concrete at a higher fiber volume fraction. It was also found that the best solution to enhance both ductility and strength of columns using FRC jacket is to include a minimum of both fiber content and reinforcement in the jacketing layer. The observations of this study reveal the great potential of the use of FRC jackets in retrofitting of structural members, especially columns in seismic regions. [ABSTRACT FROM AUTHOR]

Tooth enamel secreted by ameloblasts (AMs) is the hardest material in the human body, acting as a shield to protect the teeth. However, the enamel is gradually damaged or partially lost in over 90% of adults and cannot be regenerated due to a lack of ameloblasts in erupted teeth. Here, we use single-cell combinatorial indexing RNA sequencing (sci-RNA-seq) to establish a spatiotemporal single-cell census for the developing human tooth and identify regulatory mechanisms controlling the differentiation process of human ameloblasts. We identify key signaling pathways involved between the support cells and ameloblasts during fetal development and recapitulate those findings in human ameloblast in vitro differentiation from induced pluripotent stem cells (iPSCs). We furthermore develop a disease model of amelogenesis imperfecta in a three-dimensional (3D) organoid system and show AM maturation to mineralized structure in vivo. These studies pave the way for future regenerative dentistry. [Display omitted] • Single-cell census of human tooth development (9–22 gw) defines the major cell types • TopPath analysis identifies key signaling pathways in human ameloblast development • Human ameloblast differentiation achieved from iPSCs for future enamel studies • 3D organoid system models amelogenesis imperfecta, advancing enamel therapies Alghadeer et al. identify, using advanced sequencing techniques, key insights into the development and regeneration of tooth enamel. By identifying regulatory mechanisms and successfully differentiating human ameloblasts in vitro , this study may define tools for future therapies targeting enamel-related genetic diseases and advancements in regenerative dentistry. [ABSTRACT FROM AUTHOR]

Collagen triple helices fold slowly and inefficiently, often requiring adjacent globular domains to assist this process. In the Streptococcus pyogenes collagen-like protein Scl2, a V domain predicted to be largely a-helical, occurs N-terminal to the collagen triple helix (CL). Here, we replace this natural trimerization domain with a de novo designed, hyperstable, parallel, three-stranded, a-helical coiled coil (CC), either at the N terminus (CC-CL) or the C terminus (CL-CC) of the collagen domain. CD spectra of the constructs are consistent with additivity of independently and fully folded CC and CL domains, and the proteins retain their distinctive thermal stabilities, CL at ∼37 °C and CC at >90 °C. Heating the hybrid proteins to 50 °C unfolds CL, leaving CC intact, and upon cooling, the rate of CL refolding is somewhat faster for CL-CC than for CC-CL. A construct with coiled coils on both ends, CC-CL-CC, retains the ∼37 °C thermal stability for CL but shows less triple helix at low temperature and less denaturation at 50 °C. Most strikingly however, in CC-CL-CC, the CL refolds slower than in either CC-CL or CL-CC by almost two orders of magnitude. We propose that a single CC promotes folding of the CL domain via nucleation and in-register growth from one end, whereas initiation and growth from both ends in CC-CL-CC results in mismatched registers that frustrate folding. Bioinformatics analysis of natural collagens lends support to this because, where present, there is generally only one coiled-coil domain close to the triple helix, and it is nearly always N-terminal to the collagen repeat. [ABSTRACT FROM AUTHOR]

Plusieurs études suggèrent que les interventions multimodales, combinant la remédiation cognitive, l'entraînement cognitif et l'exercice physique, peuvent avoir un impact positif sur les performances cognitives et le bien-être. Toutefois, ces interventions, souvent peu écologiques, peuvent engendrer un stress important. Le présent projet vise à documenter l'effet physiologique et neurocognitif d'une visite au musée auprès de personnes en santé. Cette étude vise à recruter six participants adultes. Ils auront à remplir des questionnaires (Visual analog stress, ASTA, Warwick-Edinburgh Mental Well-being Scale, EQ-5D) et devront compléter une brève batterie neuropsychologique, avant et après la visite muséale. Cette visite sera réalisée avec un système d'imagerie cérébrale portable qui permettra de mesurer l'activité cérébrale sur la majeure partie du cortex. Une diminution significative des performances aux échelles de mesures du stress et de l'état anxieux sont attendues ainsi qu'une augmentation significative du score à l'échelle de mesure du bien-être et ce, entre le début et la fin de la visite du musée. De plus, il est attendu d'observer une augmentation de l'activité corticale (cortex préfrontal) corrélée à la diminution de l'état de stress entre le début et la fin de la visite. Ce projet permettra de fournir des informations utiles pour proposer une intervention accessible et écologique visant à diminuer l'état anxieux et le stress tout en favorisant une augmentation de la perception de bien-être pour les patients et pour la population en général. Projet MOB-MBAM : Caractériser l'interaction environnement–personne lors d'une visite muséale : une étude de faisabilité de collectes de données multiples et ponctuelles de la mobilité dans l'espace public. Volet 2 : les 6 sous-projets. [ABSTRACT FROM AUTHOR]