Nanoporous Membranes of Densely Packed Carbon Nanotubes Formed by Lipid-Mediated Self-Assembly

Nanofiltration technology faces the competing challenges of achieving high fluid flux through uniformly narrow pores of a mechanically and chemically stable filter. Supported dense-packed 2D-crystals of single-walled carbon nanotube (CNT) porins with ∼1 nm wide pores could, in principle, meet these challenges. However, such CNT membranes cannot currently be synthesized at high pore density. Here, we use computer simulations to explore lipid-mediated self-assembly as a route toward densely packed CNT membranes, motivated by the analogy to membrane-protein 2D crystallization. In large-scale coarse-grained molecular dynamics (MD) simulations, we find that CNTs in lipid membranes readily self-assemble into large clusters. Lipids trapped between the CNTs lubricate CNT repacking upon collisions of diffusing clusters, thereby facilitating the formation of large ordered structures. Cluster diffusion follows the Saffman-Delbrück law and its generalization by Hughes, Pailthorpe, and White. On longer time scales, we expect the formation of close-packed CNT structures by depletion of the intervening shared annular lipid shell, depending on the relative strength of CNT-CNT and CNT-lipid interactions. Our simulations identify CNT length, diameter, and end functionalization as major factors for the self-assembly of CNT membranes

Climate and disease in historical urban space: evidence from 19th century Poznań, Poland

This study examines the relationship between temperature levels and precipitation amounts as explanatory variables for the probability of death due to waterborne and airborne diseases in historical urban space. To date, the literature has not focused on the climatological epidemiology of 19th century Polish urban areas. We used individual mortality data from Poznań parish death registers between 1850 and 1900. Each deceased individual was assigned average monthly temperature values and precipitation amounts in the month of death, LAG1 (1-month-lagged) temperature and LAG1 rainfall, and place of residence. We studied the relationship between weather conditions and mortality using formalized statistical models reflecting the discrete nature of the response data (via multinomial logistic regression). Lagged monthly average temperature levels and lagged monthly average precipitation amounts were better predictors of airborne and waterborne disease mortality than the concurrent (non-lagged) monthly averages. The lagged effects of temperature and precipitation on waterborne and airborne diseases were significant (except for the smooth lagged average monthly temperature effect for airborne diseases). There was also significant spatial heterogeneity (differences among city quarters) in the prevalence of deaths due to waterborne and airborne diseases.</p

Psychological preparation and postoperative outcomes for adults undergoing surgery under general anaesthesia

Acknowledgements We wish to dedicate this work to the memory of Christian Osmer, a dedicated, caring doctor who was committed to achieving the best care for his patients and their relatives. He saw his contribution to this project as a way of advancing best care for surgical patients. We are very grateful for his valuable input to this work and the pleasure we had in working with him. We are grateful to Karen Hovhanisyan (former Trials Search Co-ordinator, Cochrane Anaesthesia, Critical and Emergency Care Group (ACE)) for carrying out the electronic database searches and to Jane Cracknell (Managing Editor, ACE) for her support throughout the review process. We would also like to thank W Alastair Chambers and Manjeet Shehmar for clinical advice relating to judgements about general anaesthesia usage, and Yvonne Cooper and Louise Pike who retrieved documents and screened papers as research assistants in earlier stages of the review. We are grateful to the following colleagues who helped us with foreign language papers - either by screening papers or by providing translation: Stefano Carrubba, Chuan Gao, Chen Ji, Kate Rhie, Reza Roudsari and Alena Vasianovich. We would like to thank Andy Smith (content editor), Nathan Pace (statistical editor), Michael Donnelly, Allan Cyna and Michael Wang (peer reviewers), and Shunjie Chua (consumer referee) for their help and editorial advice during the preparation of this systematic review. We would also like to thank Andrew Smith (content editor), Nathan Pace (statistical editor), Michael Wang and Allan Cyna (peer reviewers), and Lynda Lane (Cochrane Consumer Network representative) for their help and editorial advice during the preparation of the protocol (Powell 2010). Sources of support Internal sources Manchester Centre for Health Psychology, University of Manchester, UK. An award of £2000 was received to support research assistant costs. External sources British Academy, UK. We received a small research grant of £7480 to support research assistant costs.Peer reviewedPublisher PD

Atomistic simulation of PDADMAC/PSS oligoelectrolyte multilayers: Overall comparison of tri- And tetra-layer systems

By employing large-scale molecular dynamics simulations of atomistically resolved oligoelectrolytes in aqueous solutions, we study in detail the first four layer-by-layer deposition cycles of an oligoelectrolyte multilayer made of poly(diallyl dimethyl ammonium chloride)/poly(styrene sulfonate sodium salt) (PDADMAC/PSS). The multilayers are grown on a silica substrate in 0.1 M NaCl electrolyte solutions and the swollen structures are then subsequently exposed to varying added salt concentration. We investigated the microscopic properties of the films, analyzing in detail the differences between three- and four-layer systems. Our simulations provide insights into the early stages of growth of a multilayer, which are particularly challenging for experimental observations. We found rather strong complexation of the oligoelectrolytes, with fuzzy layering of the film structure. The main charge compensation mechanism is for all cases intrinsic, whereas extrinsic compensation is relatively enhanced for the layer of the last deposition cycle. In addition, we quantified other fundamental observables of these systems, such as the film thickness, water uptake, and overcharge fractions for each deposition layer. This journal is © The Royal Society of Chemistry

Segmenting Motion Capture Data Using a Qualitative Analysis

Many interactive 3D games utilize motion capture for both character animation and user input. These applications require short, meaningful sequences of data. Manually producing these segments of motion capture data is a laborious, time-consuming process that is impractical for real-time applications. We present a method to automatically produce semantic segmentations of general motion capture data by examining the qualitative properties that are intrinsic to all motions, using Laban Movement Analysis (LMA). LMA provides a good compromise between high-level semantic features, which are difficult to extract for general motions, and lowlevel kinematic features, which often yield unsophisticated segmentations. Our method finds motion sequences which exhibit high output similarity from a collection of neural networks trained with temporal variance. We show that segmentations produced using LMA features are more similar to manual segmentations, both at the frame and the segment level, than several other automatic segmentation methods

The Water Load Test As a Measure of Gastric Interoception: Development of a Two-Stage Protocol and Application to a Healthy Female Population

The sensitivity for one’s own internal body signals (i.e., interoception) has been demonstrated to play an important role in the pathogenesis of eating and weight disorders. Most previous measures assessing interoceptive processing have not, or only partly, captured perception of hunger and satiety cues, which is a core aspect of interoceptive deficits in eating disorders. In addition, methods used to measure sensitivity to gastric signals are heterogeneous and findings inconsistent. The primary aim of the present study was to establish a standardised test to measure gastric interoception, and to provide normative data using a non-clinical adult sample. The two-step Water Load Test (WLT-II) involves ingestion of non-caloric water until perceived satiation (step 1) and until maximum fullness (step 2). The WLT-II consists of several variables: Besides volumes of water ingested until satiation and maximum fullness expressed in ml, percentage of satiation to maximum fullness is calculated as an individual index of gastric interoception that is not confounded with stomach capacity. Ninety-nine healthy women participated in the study. Measures included the WLT-II, the heartbeat tracking test, a self-report questionnaire assessing subjective sensations, and the Eating Disorder Inventory-2. Twenty-eight participants underwent test-retest of the WLT-II. Results suggest that the WLT-II is a valid and reliable measure of gastric interoception. Importantly, satiation volume and percentage of satiation to maximum fullness were strongly positively related to self-reported bulimic symptoms, indicating that the WLT-II could emerge as a useful clinical tool to measure interoceptive processing in the field of eating disorders

Enhanced sequential carrier capture into individual quantum dots and quantum posts controlled by surface acoustic waves

Individual self-assembled Quantum Dots and Quantum Posts are studied under the influence of a surface acoustic wave. In optical experiments we observe an acoustically induced switching of the occupancy of the nanostructures along with an overall increase of the emission intensity. For Quantum Posts, switching occurs continuously from predominantely charged excitons (dissimilar number of electrons and holes) to neutral excitons (same number of electrons and holes) and is independent on whether the surface acoustic wave amplitude is increased or decreased. For quantum dots, switching is non-monotonic and shows a pronounced hysteresis on the amplitude sweep direction. Moreover, emission of positively charged and neutral excitons is observed at high surface acoustic wave amplitudes. These findings are explained by carrier trapping and localization in the thin and disordered two-dimensional wetting layer on top of which Quantum Dots nucleate. This limitation can be overcome for Quantum Posts where acoustically induced charge transport is highly efficient in a wide lateral Matrix-Quantum Well.Comment: 11 pages, 5 figure

Urbanization and mortality in Britain, c. 1800-50.

In the long-running debate over standards of living during the industrial revolution, pessimists have identified deteriorating health conditions in towns as undermining the positive effects of rising real incomes on the 'biological standard of living'. This article reviews long-run historical relationships between urbanization and epidemiological trends in England, and then addresses the specific question: did mortality rise especially in rapidly growing industrial and manufacturing towns in the period c. 1830-50? Using comparative data for British, European, and American cities and selected rural populations, this study finds good evidence for widespread increases in mortality in the second quarter of the nineteenth century. However, this phenomenon was not confined to 'new' or industrial towns. Instead, mortality rose in the 1830s especially among young children (aged one to four years) in a wide range of populations and environments. This pattern of heightened mortality extended between c. 1830 and c. 1870, and coincided with a well-established rise and decline in scarlet fever virulence and mortality. The evidence presented here therefore supports claims that mortality worsened for young children in the middle decades of the nineteenth century, but also indicates that this phenomenon was more geographically ubiquitous, less severe, and less chronologically concentrated than previously argued.Leverhulme Trust (award RPG-2012-803) Wellcome Trust (award no. 103322