715 research outputs found
Sticking and sliding of lipid bilayers on deformable substrates
We examine here the properties of lipid bilayers coupled to deformable substrates. We show that by changing the extent of the substrate hydrophilicity, we can control the membrane–substrate coupling and the response of the bilayer to strain deformation. Our results demonstrate that lipid bilayers coupled to flexible substrates can easily accommodate large strains, form stable protrusions and open reversibly pores. These properties, which differ significantly from those of free standing membranes, can extend the applications of the current lipid technologies. Moreover, such systems better capture the mechanical architecture of the cell interface and can provide insights into the capacity of cells to reshape and respond to mechanical perturbations
Confined bilayers passively regulate shape and stress
Lipid membranes are commonly confined to adjacent subcellular structures or to artificial substrates and particles. We develop an experimental and theoretical framework to investigate the mechanics of confined membranes, including the influence of adhesion, strain, and osmotic pressure. We find that supported lipid bilayers respond to stress by nucleating and evolving spherical and tubular protrusions. In cells, such transformations are generally attributed to proteins. Our results offer insights into the mechanics of cell membranes and can further extend the applications of supported bilayers
Assessment of Children with Autism Spectrum Disorder and Post-Assessment Meeting with Parents: Some Issues of Planning and Professional Attitude
The authors, child psychiatrists and clinical psychologists, conducting team assessment of children with developmental disabilities (including autism spectrum disorder) for more than two decades, present some important in their view issues and recommendations concerning planning and proceeding of assessment and post-assessment meetings with parents. It is essential to ensure not only an accurate assessment protocol and diagnosis, but also to "attune" to parents in order to facilitate their understanding and more positive use of assessment outcome results. Parents need further support to "survive" psychically the post - assessment period and to provide for adequate interventions for their child
Confined bilayers passively regulate shape and stress
Lipid membranes are commonly confined to adjacent subcellular structures or to artificial substrates and particles. We develop an experimental and theoretical framework to investigate the mechanics of confined membranes, including the influence of adhesion, strain, and osmotic pressure. We find that supported lipid bilayers respond to stress by nucleating and evolving spherical and tubular protrusions. In cells, such transformations are generally attributed to proteins. Our results offer insights into the mechanics of cell membranes and can further extend the applications of supported bilayers.Peer ReviewedPostprint (author's final draft
Asperger’s Syndrome in a Clinical Sample: Reasons for Referral and Comorbidity
Asperger’s Syndrome (AS) is an autism spectrum disorder without mental retardation and language delay. AS often remains unrecognized until these children fail to adapt to school or kindergarten. The comorbid psychiatric disorders, achieving clinical significance, were considered as another pathway to diagnosis. This study is aimed to elucidate the reasons for referral, the frequency and the kinds of comorbidities in a clinical sample of consecutive cases of children and adolescents with AS. To this objective, clinical records of children and adolescents, who have received a DSM-IV diagnosis of AS after multidisciplinary assessment in a given time period were reviewed. After excluding 3 cases due to insufficient information, 24 cases of children and adolescents with Asperger’s Syndrome (23 boys and one girl) were identified. The mean age at the time of assessment and receiving diagnosis was 9.6 yrs. (age range 4 to 17 years). In twenty-one (87%) of the cases the reason for referral was an episode of disorganized behavior following an attempt to enrollthe child at school or kindergarten, and more rare referral occurred within the significant school transition period. In the remaining 3 cases, the reason for referral was a comorbid condition. Comorbid conditions identified at the moment of assessment include: ADHD documented in 4 cases, tics in 3 cases, obsessive-compulsive behaviors in 4 cases, Stereotypic Movement Disorder or Trichotilomania in 4 of the cases. Within the clinical sample, a priori expected to include relatively severe cases, a higher frequency of comorbidity was found as compared to the rates in the general population. Adjustment reactions and comorbidities occasioned the refer
Early Assessment of Mental Development in Children with Autism Spectrum Disorder (ASD) and other Neurodevelopmental Disorders - Sharing of Clinical Experience
The authors present a synthesised review of the methods for assessing mental development and autism, with an emphasis on the general tendency to reduce the age of diagnosis. Based on clinical experience, a number of particularities are described in terms of: testing, working with parents, observing and reflecting on the nature and meaning of autistic behaviours. On focus is a toolkit for detailed assessment of mental development that was elaborated within the inter-university cooperation between Sofia Medical University and Universite catholique de Louvain (UCL) - Belgium. Illustrated and discussed are typical profiles of cognitive and socio-communicative functioning of children with ASD and other neurodevelopmental disorders, which help a differential diagnosis to be made by the multidisciplinary clinical team. Further described are the advantages of early assessment of mental development as a basis for future educational and therapeutic programs
Shape transformations of lipid bilayers following rapid cholesterol uptake
High cholesterol levels in the blood increase the risk of atherosclerosis. A common explanation is that the cholesterol increase in the plasma membrane perturbs the shape and functions of cells by disrupting the cell signaling pathways and the formation of membrane rafts. In this work, we show that after enhanced transient uptake of cholesterol, mono-component lipid bilayers change their shape similarly to cell membranes in vivo. The bilayers either expel lipid protrusions or spread laterally as a result of the ensuing changes in their lipid density, the mechanical constraints imposed on them, and the properties of cyclodextrin used as a cholesterol donor. In light of the increasingly recognized link between membrane tension and cell behavior, we propose that the physical adaptation of the plasma membrane to cholesterol uptake may play a substantial role in the biological response
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Search for physics beyond the standard model in events with Ď„ leptons, jets, and large transverse momentum imbalance in pp collisions at [Formula: see text].
A search for physics beyond the standard model is performed with events having one or more hadronically decaying Ď„ leptons, highly energetic jets, and large transverse momentum imbalance. The data sample corresponds to an integrated luminosity of 4.98 fb-1 of proton-proton collisions at [Formula: see text] collected with the CMS detector at the LHC in 2011. The number of observed events is consistent with predictions for standard model processes. Lower limits on the mass of the gluino in supersymmetric models are determined
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