2,663 research outputs found
Identifying suitable substrates for high-quality graphene-based heterostructures
We report on a scanning confocal Raman spectroscopy study investigating the
strain-uniformity and the overall strain and doping of high-quality chemical
vapour deposited (CVD) graphene-based heterostuctures on a large number of
different substrate materials, including hexagonal boron nitride (hBN),
transition metal dichalcogenides, silicon, different oxides and nitrides, as
well as polymers. By applying a hBN-assisted, contamination free, dry transfer
process for CVD graphene, high-quality heterostructures with low doping
densities and low strain variations are assembled. The Raman spectra of these
pristine heterostructures are sensitive to substrate-induced doping and strain
variations and are thus used to probe the suitability of the substrate material
for potential high-quality graphene devices. We find that the flatness of the
substrate material is a key figure for gaining, or preserving high-quality
graphene.Comment: 6 pages, 5 figure
The PLAC1-homology region of the ZP domain is sufficient for protein polymerisation
BACKGROUND: Hundreds of extracellular proteins polymerise into filaments and matrices by using zona pellucida (ZP) domains. ZP domain proteins perform highly diverse functions, ranging from structural to receptorial, and mutations in their genes are responsible for a number of severe human diseases. Recently, PLAC1, Oosp1-3, Papillote and CG16798 proteins were identified that share sequence homology with the N-terminal half of the ZP domain (ZP-N), but not with its C-terminal half (ZP-C). The functional significance of this partial conservation is unknown. RESULTS: By exploiting a highly engineered bacterial strain, we expressed in soluble form the PLAC1-homology region of mammalian sperm receptor ZP3 as a fusion to maltose binding protein. Mass spectrometry showed that the 4 conserved Cys residues within the ZP-N moiety of the fusion protein adopt the same disulfide bond connectivity as in full-length native ZP3, indicating that it is correctly folded, and electron microscopy and biochemical analyses revealed that it assembles into filaments. CONCLUSION: These findings provide a function for PLAC1-like proteins and, by showing that ZP-N is a biologically active folding unit, prompt a re-evaluation of the architecture of the ZP domain and its polymers. Furthermore, they suggest that ZP-C might play a regulatory role in the assembly of ZP domain protein complexes
The Role of Solid Friction in the Sedimentation of Strongly Attractive Colloidal Gels
We study experimentally and theoretically the sedimentation of gels made of
strongly aggregated colloidal particles, focussing on the long time behavior,
when mechanical equilibrium is asymptotically reached. The asymptotic gel
height is found to vary linearly with the initial height, a finding in stark
contrast with a recent study on similar gels [Manley \textit{et al.} 2005
\textit{Phys. Rev. Lett.} \textbf{94} 218302]. We show that the asymptotic
compaction results from the balance between gravity pull, network elasticity,
and solid friction between the gel and the container walls. Based on these
ingredients, we propose a simple model to account for the dependence of the
height loss on the initial height and volume fraction. As a result of our
analysis, we show that the static friction coefficient between the gel and the
container walls strongly depends on volume fraction: the higher the volume
fraction, the weaker the solid friction. This nonintuitive behavior is
explained using simple scaling arguments.Comment: 13 pages, 5 figures. Submitted to JSTA
Neurodevelopmental consequences in offspring of mothers with preeclampsia during pregnancy: underlying biological mechanism via imprinting genes
Purpose
Preeclampsia is known to be a leading cause of mortality and morbidity among mothers and their infants. Approximately 3â8% of all pregnancies in the US are complicated by preeclampsia and another 5â7% by hypertensive symptoms. However, less is known about its long-term influence on infant neurobehavioral development. The current review attempts to demonstrate new evidence for imprinting gene dysregulation caused by hypertension, which may explain the link between maternal preeclampsia and neurocognitive dysregulation in offspring.
Method
Pub Med and Web of Science databases were searched using the terms âpreeclampsia,â âgestational hypertension,â âimprinting genes,â âimprinting dysregulation,â and âepigenetic modification,â in order to review the evidence demonstrating associations between preeclampsia and suboptimal child neurodevelopment, and suggest dysregulation of placental genomic imprinting as a potential underlying mechanism.
Results
The high mortality and morbidity among mothers and fetuses due to preeclampsia is well known, but there is little research on the long-term biological consequences of preeclampsia and resulting hypoxia on the fetal/child neurodevelopment. In the past decade, accumulating evidence from studies that transcend disciplinary boundaries have begun to show that imprinted genes expressed in the placenta might hold clues for a link between preeclampsia and impaired cognitive neurodevelopment. A sudden onset of maternal hypertension detected by the placenta may result in misguided biological programming of the fetus via changes in the epigenome, resulting in suboptimal infant development.
Conclusion
Furthering our understanding of the molecular and cellular mechanisms through which neurodevelopmental trajectories of the fetus/infant are affected by preeclampsia and hypertension will represent an important first step toward preventing adverse neurodevelopment in infants
1st EFORT European Consensus: Medical & Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devices
Innovations in Orthopaedics and Traumatology have contributed to the achievement of a high-quality level of care in musculoskeletal disorders and injuries over the past decades. The applications of new implants as well as diagnostic and therapeutic techniques in addition to implementation of clinical research, have significantly improved patient outcomes, reduced complication rates and length of hospital stay in many areas.
However, the regulatory framework is extensive, and there is a lack of understanding and clarity in daily practice what the meaning of clinical & preâclinical evidence as required by the MDR is. Thus, understanding and clarity are of utmost importance for introduction of new implants and implant-related instrumentation in combination with surgical technique to ensure a safe use of implants and treatment of patients.
Therefore EFORT launched IPSI, The Implant and Patient Safety Initiative, which starting from an inaugural workshop in 2021 issued a set of recommendations, notably through a subsequent Delphi Process involving the National Member Societies of EFORT, European Specialty Societies as well as International Experts. These recommendations provide surgeons, researchers, implant manufacturers as well as patients and health authorities with a consensus of the development, implementation, and dissemination of innovation in the field of arthroplasty.
The intended key outcomes of this 1st EFORT European Consensus on âMedical & Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devicesâare consented, practical pathways to maintain innovation and optimisation of orthopaedic products and workflows within the boundaries of MDR 2017/745. Open Access practical guidelines based on adequate, state of the art pre-clinical and clinical evaluation methodologies for the introduction of joint replacements and implant-related instrumentation shall provide hands-on orientation for orthopaedic surgeons, research institutes and laboratories, orthopaedic device manufacturers, Notified Bodies but also for National Institutes and authorities, patient representatives and further stakeholders.
We would like to acknowledge and thank the Scientific Committee members, all International Expert Delegates, the Delegates from European National & Specialty Societies and the Editorial Team for their outstanding contributions and support during this EFORT European Consensus
Aspects and Challenges of Resource Use Measurement in Health Economics:Towards a Comprehensive Measurement Framework
BACKGROUND: While the methods for conducting health economics research in general are improving, current guidelines provide limited guidance regarding resource use measurement (RUM). Consequently, a variety of methods exists, yet there is no overview of aspects to consider when deciding on the most appropriate RUM methodology. Therefore, this study aims to (1) identify and categorize existing knowledge regarding aspects of RUM, and (2) develop a framework that provides a comprehensive overview of methodological aspects regarding RUM. METHODS: Relevant articles were identified by enrolling a search string in six databases and handsearching the DIRUM database. Included articles were descriptively reviewed and served as input for a comprehensive framework. Health economics experts were involved during the process to establish the frameworkâs face validity. RESULTS: Forty articles were included in the scoping review. The RUM framework consists of four methodological RUM domains: âWhom to measureâ, addressing whom to ask and whom to measure; âHow to measureâ, addressing the different approaches of measurement; âHow often to measureâ, addressing recall period and measurement patterns; and âAdditional considerationsâ, which covers additional aspects that are essential for further refining the methodologies for measurement. Evidence retrieved from the scoping review was categorized according to these domains. CONCLUSION: This study clustered the aspects of RUM methodology in health economics into a comprehensive framework. The results may guide health economists in their decision making regarding the selection of appropriate RUM methods and developing instruments for RUM. Furthermore, policy makers may use these findings to review study results from an evidence-based perspective. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40273-021-01048-z
Exploring the identification, validation, and categorization of costs and benefits of education in mental health: the PECUNIA project
BackgroundMental health problems can lead to costs and benefits in other sectors (e.g. in the education sector) in addition to the healthcare sector. These related costs and benefits are known as intersectoral costs and benefits (ICBs). Although some ICBs within the education sector have been identified previously, little is known about their extensiveness and transferability, which is crucial for their inclusion in health economics research.ObjectivesThe aim of this study was to identify ICBs in the education sector, to validate the list of ICBs in a broader European context, and to categorize the ICBs using mental health as a case study.MethodsPreviously identified ICBs in the education sector were used as a basis for this study. Additional ICBs were extracted from peer-reviewed literature in PubMed and grey literature from six European countries. A comprehensive list of unique items was developed based on the identified ICBs. The list was validated by surveying an international group of educational experts. The survey results were used to finalize the list, which was categorized according to the care atom.ResultsAdditional ICBs in the education sector were retrieved from ninety-six sources. Fourteen experts from six European countries assessed the list for completeness, clarity, and relevance. The final list contained twenty-four ICBs categorized into input, throughput, and output.ConclusionBy providing a comprehensive list of ICBs in the education sector, this study laid further foundations for the inclusion of important societal costs in health economics research in the broader European context
Clarifying terminology and definitions in education services for mental health users:A disambiguation study
In the wake of the mental health crisis in children and adolescents, the coordination of education and mental health services has become a global priority. However, differing terminologies and classifications across sectors, hinder effective comparison. The classification in education focuses mainly on outputs like qualifications or throughputs like teaching programs. This proof-of-concept study tested the applicability of a standard classification of health services, the Description and Evaluation of Services and DirectoriEs (DESDE), to evaluate education services for mental health users in the context of Spain and The Netherlands. It was conducted alongside the PECUNIA project, that sought to develop methods for the assessment of mental health costs and outcomes in different sectors. The study followed an ontoterminology approach involving: 1) identification of services from a predefined list of 46 resource-use items, 2) disambiguation of identified services with the DESDE, and classifying them as accurate, ambiguous, vague or confuse; and 3) external validation by an expert panel. The analysis was conducted at the level of type of resource, target population and care provision. From the initial list, only ten of the resources could be categorized as services using DESDE, and not activities, interventions or professionals. Only four of them (8,65%) were accurate across all disambiguation categories. Experts were unaware of terminology problems in classification of service provision in the education sector. Classifications and glossaries can clarify service naming, description and costing allowing comparative effectiveness analysis and facilitating cross-sectoral planning. This should be grounded in common methodologies, tools, and units of analysis
Clarifying terminology and definitions in education services for mental health users: A disambiguation study
In the wake of the mental health crisis in children and adolescents, the coordination of education and mental health services has become a global priority. However, differing terminologies and classifications across sectors, hinder effective comparison. The classification in education focuses mainly on outputs like qualifications or throughputs like teaching programs. This proof-of-concept study tested the applicability of a standard classification of health services, the Description and Evaluation of Services and DirectoriEs (DESDE), to evaluate education services for mental health users in the context of Spain and The Netherlands. It was conducted alongside the PECUNIA project, that sought to develop methods for the assessment of mental health costs and outcomes in different sectors. The study followed an ontoterminology approach involving: 1) identification of services from a predefined list of 46 resource-use items, 2) disambiguation of identified services with the DESDE, and classifying them as accurate, ambiguous, vague or confuse; and 3) external validation by an expert panel. The analysis was conducted at the level of type of resource, target population and care provision. From the initial list, only ten of the resources could be categorized as services using DESDE, and not activities, interventions or professionals. Only four of them (8,65%) were accurate across all disambiguation categories. Experts were unaware of terminology problems in classification of service provision in the education sector. Classifications and glossaries can clarify service naming, description and costing allowing comparative effectiveness analysis and facilitating cross-sectoral planning. This should be grounded in common methodologies, tools, and units of analysis
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