To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Recent infection testing algorithms (RITA) for HIV combine serological assays with epidemiological data to determine likely recent infections, indicators of ongoing transmission. In 2016, we integrated RITA into national HIV surveillance in Ireland to better inform HIV prevention interventions. We determined the avidity index (AI) of new HIV diagnoses and linked the results with data captured in the national infectious disease reporting system. RITA classified a diagnosis as recent based on an AI < 1.5, unless epidemiological criteria (CD4 count <200 cells/mm3; viral load <400 copies/ml; the presence of AIDS-defining illness; prior antiretroviral therapy use) indicated a potential false-recent result. Of 508 diagnoses in 2016, we linked 448 (88.1%) to an avidity test result. RITA classified 12.5% of diagnoses as recent, with the highest proportion (26.3%) amongst people who inject drugs. On multivariable logistic regression recent infection was more likely with a concurrent sexually transmitted infection (aOR 2.59; 95% CI 1.04–6.45). Data were incomplete for at least one RITA criterion in 48% of cases. The study demonstrated the feasibility of integrating RITA into routine surveillance and showed some ongoing HIV transmission. To improve the interpretation of RITA, further efforts are required to improve completeness of the required epidemiological data.
To systematically review studies from Irish prisons that estimate the prevalence of major mental illness, alcohol and substance misuse, and homelessness at the time of committal.
Healthcare databases were searched for studies quantifying the point prevalence for each outcome of interest. Searches were augmented by scanning of bibliographies and searches of governmental and non-governmental websites. Proportional meta-analyses were completed for each outcome.
We found eight, six and five studies quantifying the point prevalence of major mental illness, substance misuse, and homelessness respectively. Considerable heterogeneity was found for each subgroup (except psychosis where substantial heterogeneity was observed) and random effects models were used to calculate pooled percentages. The pooled percentage for psychotic disorder was 3.6% [95% confidence interval (CI) 3.0–4.2%], for affective disorder 4.3% (95% CI 2.1–7.1%), for alcohol use disorder 28.3% (95% CI 19.9–37.4%), for substance use disorder 50.9% (95% CI 37.6–64.2%) and for those who were homeless on committal 17.4% (95% CI 8.7–28.4%).
Estimates for the prevalence of psychotic illness and substance abuse amongst Irish prisoners are in keeping with international estimates of morbidity in prisons, whilst those for affective disorders are lower. The prevalence of homelessness in committal to Irish prisons is higher than some international estimates. Rates for psychoses, alcohol and substance misuse as well as homelessness in Irish prisons are significantly higher than the general population prevalence of these vulnerabilities. A need for service development is discussed.
We investigate the approximation of quadratic Dirichlet
-functions over function fields by truncations of their Euler products. We first establish representations for such
-functions as products over prime polynomials times products over their zeros. This is the hybrid formula in function fields. We then prove that partial Euler products are good approximations of an
-function away from its zeros and that, when the length of the product tends to infinity, we recover the original
-function. We also obtain explicit expressions for the arguments of quadratic Dirichlet
-functions over function fields and for the arguments of their partial Euler products. In the second part of the paper we construct, for each quadratic Dirichlet
-function over a function field, an auxiliary function based on the approximate functional equation that equals the
-function on the critical line. We also construct a parametrized family of approximations of these auxiliary functions and prove that the Riemann hypothesis holds for them and that their zeros are related to those of the associated
-function. Finally, we estimate the counting function for the zeros of this family of approximations, show that these zeros cluster near those of the associated
-function, and that, when the parameter is not too large, almost all the zeros of the approximations are simple.
In 2011 the Incidence Assay Critical Path Working Group reviewed the current state of HIV incidence assays and helped to determine a critical path to the introduction of an HIV incidence assay. At that time the Consortium for Evaluation and Performance of HIV Incidence Assays (CEPHIA) was formed to spur progress and raise standards among assay developers, scientists and laboratories involved in HIV incidence measurement and to structure and conduct a direct independent comparative evaluation of the performance of 10 existing HIV incidence assays, to be considered singly and in combinations as recent infection test algorithms. In this paper we report on a new framework for HIV incidence assay evaluation that has emerged from this effort over the past 5 years, which includes a preliminary target product profile for an incidence assay, a consensus around key performance metrics along with analytical tools and deployment of a standardized approach for incidence assay evaluation. The specimen panels for this evaluation have been collected in large volumes, characterized using a novel approach for infection dating rules and assembled into panels designed to assess the impact of important sources of measurement error with incidence assays such as viral subtype, elite host control of viraemia and antiretroviral treatment. We present the specific rationale for several of these innovations, and discuss important resources for assay developers and researchers that have recently become available. Finally, we summarize the key remaining steps on the path to development and implementation of reliable assays for monitoring HIV incidence at a population level.
Navigators help rural older adults with advanced illness and their families connect to needed resources, information, and people to improve their quality of life. This article describes the process used to engage experts – in rural aging, rural palliative care, and navigation – as well as rural community stakeholders to develop a conceptual definition of navigation and delineate navigation competencies for the care of this population. A discussion paper on the important considerations for navigation in this population was developed followed by a four-phased Delphi process with 30 expert panel members. Study results culminated in five general navigation competencies for health care providers caring for older rural persons and their families at end of life: provide patient/family screening; advocate for the patient/family; facilitate community connections; coordinate access to services and resources; and promote active engagement. Specific competencies were also developed. These competencies provide the foundation for research and curriculum development in navigation.
Observations of metal absorption lines in the spectra of QSOs out to z > 6 are providing an important probe into the enrichment and ionization state of the intergalactic medium (IGM) at the tail end of reionization. Using simulations with four different feedback models, including the Illustris and Sherwood simulations, we investigate how the overall incidence rate and equivalent width distribution of metal-line absorbers varies with the galactic wind scheme. The low-ionization absorbers are reasonably insensitive to the feedback implementation, with all models reasonably close to the observed incidence rate of O i absorbers. However, all of our models struggle to reproduce the observations of C iv, which is probing overdensities close to the mean at z ~ 6, suggesting that the metals are not being transported out into the IGM efficiently enough in these simulations.
This study is a subjective synthesis of the work of many academics, supervisors and practitioners on the topic of liquidity and many of its multiple aspects. It borrows heavily and freely from those works in the pursuit of coherence, as this subject can be both confused and confusing. Although many hypotheses, both established and speculative, are referred to, none is proposed in this paper. In order to be of possible use to a range of readers, it roams from the most basic and elementary to some of the most recent and advanced. In pursuit of brevity and readability, in many instances it can do little more than introduce a particular feature and leave further investigation to the reader. Liquidity is clearly a topic with much unfinished business. Our ambition in writing this paper is threefold: first, to raise awareness amongst actuaries of the wide-ranging implications for actuarial work of liquidity; second, to bring some coherence to the manifold measures and uses of the concept of liquidity by attempting to synthesise some of the key elements of knowledge today; finally, to highlight some of the more high profile and open questions relevant for actuarial work. This paper makes many references to behaviour during the crisis and its aftermath; however, it is not intended to be a forensic analysis of the crisis attributing causality. The crisis has simply served as an experiment during which many things became observable.
We present an integrated readout technique for interrogating the suspension height of micro-electro-mechanical systems (MEMS) structures. This readout technique is envisaged to be useful in applications such as MEMS-based biological and chemical sensing, where it is necessary to obtain the accurate position of a MEMS beam. The approach is based on the suspended MEMS structure modulating light transmission in an underlying optical waveguide via Fabry-Perrot phenomena. The performance of the technique is predicted via finite difference time domain (FDTD) simulations the results of which are confirmed by experimental measurements.
Hemangioblastomas are benign vascular tumors of the central nervous system that occur sporadically or in association with von Hippel-Lindau disease. These tumors are characteristically composed of a dense capillary network with intervening stromal/interstitial cells. To date, the histogenesis of hemangioblastoma remains unclear. We hypothesize that hemangioblastomas arise from a defective mesodermal stem cell, which gives rise to the atypical vasculature.
To test our hypothesis, we have characterized the cellular composition of hemangioblastomas by immunophenotyping pluripotent and committed stem cells and vascular endothelial cells.
Our findings show that hemangioblastoma endothelial cells are positive for CD133, a stem and progenitor cell marker. Vascular endothelial cells also expressed nuclear Oct4. In addition to the endothelium, both CD133 and Oct4 were present in stromal and perivascular cells. Interestingly, neither the endothelium nor the stromal cells expressed Sox2 or Nanog suggesting a committed stem cell phenotype.
From these findings, we believe that hemangioblastoma stromal cells are committed stem cells producing both vascular cell types. The findings also show an unusual CD133-positive endothelial phenotype in hemangioblastoma.
Contemporary tort theory is dominated by a debate between legal economists and corrective-justice theorists. Legal economists suppose that tortfeasors and tortious wrongs are false targets for cheapest cost-avoiders and avoidable future losses. Corrective-justice theorists argue powerfully that the economic account of tort as search for cheapest cost-avoiders with respect to future accidents does not capture the most fundamental fact about tort adjudication, namely, that the reason we hold defendants liable in tort is that they have wronged their victims and should therefore repair the harm they have done. Deterring cheapest cost-avoiders from committing future harms no more justifies imposing liability in tort than deterring future crime justifies hanging the innocent. This is a powerful critique of the economic theory of tort, but it overshoots the mark. As an account of tort law, corrective justice puts the cart before the horse Tort is a law of wrongs, not just a law of redress for wrongs. Repairing harm wrongly done is the next best way of complying with an obligation not to do harm wrongly in the first place. Rights and remedies form a unity in which rights have priority. Corrective justice is thus an essential but subordinate aspect of tort. This paper develops this line of criticism of corrective-justice theory and offers an alternative account of tort that places primary norms of harm avoidance and respect for rights at its center. On this conception, tort is—as the corrective-justice theorists rightly insist—a law of wrongs, but its distinctiveness lies in the content and character of the wrongs with which it is concerned. At its core, tort is concerned with protecting essential conditions of individual agency.
Our study describes the synthesis of novel nanoscale Pd cage and wires whose sizes and shapes are templated by mesoporous matrices. The templates used are cubic phase MCM-48 and hexagonal phase CnMCM-41 (n = 16, and 22), SBA-15, which have pore diameters of ∼3, ∼3.8, ∼4.7, and ∼9 nm, respectively. For Pd@MCM-48, the Pd metal forms spherical domains (∼38 nm) consisting of three dimensionally interconnected into Pd arrays; for Pd@SBA-15 and Pd@MCM-41, the Pd metal forms of one-dimensional wires. Etching out the matrix produces porous Pd cages (pore sizes of ∼1.5 - 2.0 nm) with retaining original domain sizes of ∼38 nm; similarly Pd@SBA-15 and Pd@MCM-41 afford freestanding Pd nanowires. All the materials are examined by TEM, XRD, BET, and EDAX analysis. Furthermore, the thermal behavior of Pd nanowire is briefly described.
The magnetic properties of nanosized iron-oxo molecular clusters have been investigated via Mössbauer spectroscopy and compared to those of silica coated iron-oxide nanoparticles. The clusters, prepared by controlled hydrolytic iron polymerization reactions, contain a ∼ 1.2 nm diameter magnetic core of spin-coupled iron ions surrounded by a shell of benzoate ligands. The nanoparticles, prepared via sol-gel synthesis, contain a ∼ 4.0 nm average diameter γ-Fe2O3 core coated by a shell of SiO2. Both systems exhibit magnetic bistability at low temperatures with estimated magnetic anisotropy constants of Keff = 0.63x105 J/m3 for the clusters and Keff = 0.55 ×105 J/m3 for the particles. The similar values of Keff indicate that these two systems experience similar degrees of strain at the core/shell interface. This is further supported by the values of the quadrupole splitting, ΔEQ=0.77 mm/s for the clusters and ΔEQ=0.75 mm/s for the particles, pointing to same degree of distortion from pure octahedral or tetrahedral symmetry at the iron coordination sites for either system. Implications of these observations for the surface atomic structure of γ-Fe2O3 nanoparticles are discussed.
We present a dynamical effective medium theory (EMT) of the dielectric properties of nanoparticle aggregates formed from DNA-linked gold nanoparticles. Experimental measurements show that such aggregateshave reduced UV extinction and plasmon bands that are considerably red-shifted and broadened relative to the plasmon absorption feature observed in spectra of dispersed colloid. The EMT, which can be used to reproduce the observed spectral changes, is tested by comparing aggregate spectra calculated using the EMT dielectric function with spectra from explicit coupled particle calculations, and good agreement is found. The EMT dielectric function is used as well in discrete dipole calculations to calculate extinction spectra for a variety of aggregate shapes not amenable to analytic solution, and the sensitivity of the spectra to aggregate shape is examined. We find that the spectra are only weakly sensitive to aggregate shape, and conclude that, when calculating extinction of the DNA-linked aggregates for comparison with experiment, spherical shapes can be assumed.
DNA was used as a scaffold for the binding of gold nanoparticles using a standard chemical technique. A DNA template was designed with amino-modified thymines located every 3.7 nm, which would allow the attachment of the carboxylic acid functionalized gold nanoparticles. The gold particles were covalently bound to the amino groups on the DNA using standard 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) chemistry in the presence of a competitor to block excess gold binding sites. The products were analyzed by transmission electron microscopy (TEM) and atomic force microscopy (AFM).
A direct synthesis of (001) oriented nanostructured CoPt thin films has been successfully achieved using a 880 J pulsed Dense Plasma Focus (DPF) device operating in a non-optimized focus mode with a low charging voltage of about 8 kV. The (001) oriented fct structured L10 phase nanostructured CoPt thin films have been synthesized directly in as-deposited sample, as verified by XRD results, without any post deposition annealing. The SEM imaging results show that nanostructured CoPt were achieved in non-optimized focus mode with agglomerate/particle size ranging from 10 to 55 nm. Furthermore, the VSM analysis shows that the as-deposited samples in non-optimized focus mode have higher coercivity (due to direct L10 phase) as compared the annealed sample and the as-deposited sample of optimized focus mode operation.
Interpenetrating Al2O3/Al composites were created by liquid-metal infiltration of alumina preforms with three-dimensional periodicity produced by a robotic deposition method. Volume-averaged lattice strains in the alumina phase were measured by synchrotron x-ray diffraction at various uniaxial compression stresses up to 350 MPa. Load transfer, which is experimentally found to occur between the aluminum and the alumina phase, is in agreement with simple rule of mixtures models. Spatially resolved measurements showed variations in load transfer at different positions within the composite for the elastic-, plastic-, and damage-deformation regimes. Using phase-enhanced imaging, the extent of damage within the composites was observed.