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Open AccessReview No Reprieve for Tasmanian Rock Art

Arts 2013, 2(4), 182-224; doi:10.3390/arts2040182

Received: 17 August 2013 / Revised: 24 September 2013 / Accepted: 24 September 2013 / Published: 17 October 2013

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Abstract

The Australian State of Tasmania, at latitude 42 degrees south, became an island about 8,000 years ago when the sea rose to its present level, following the melting of polar and glacial ice that covered much of the land mass. After that time,

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The Australian State of Tasmania, at latitude 42 degrees south, became an island about 8,000 years ago when the sea rose to its present level, following the melting of polar and glacial ice that covered much of the land mass. After that time, the Tasmanian Aboriginal rock art developed independently of mainland Australia, with its form being basically linear with some naturalistic figures and a predominance of cupules. The petroglyphs with one lithophone site occur on various rock substrates varying in hardness from granite to sandstone. Many sites exist along the western coastline that borders the Southern Ocean where the landscape in some places has changed little since the arrival of Europeans in 1803. The significance of this Tasmanian Aboriginal cultural heritage along what is now known as the Tarkine Coast, named after an Aboriginal band that once inhabited this area, was recognised by the Australian Government in February 2013 when a 21,000 ha strip, 2 km wide, was inscribed on its National Heritage Register, being one of 98 special places listed in the country. However, politics and racism hamper its management. This paper is based on the results of 40 years of field recording of the Tasmanian Aboriginal rock art sites, many of which remain unpublished. Full article

(This article belongs to the collection World Rock Art)

Open AccessArticle Spatially Interpolated Disease Prevalence Estimation Using Collateral Indicators of Morbidity and Ecological Risk

by Peter Congdon

Int. J. Environ. Res. Public Health 2013, 10(10), 5011-5025; doi:10.3390/ijerph10105011

Received: 25 August 2013 / Revised: 1 October 2013 / Accepted: 8 October 2013 / Published: 14 October 2013

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Abstract

This paper considers estimation of disease prevalence for small areas (neighbourhoods) when the available observations on prevalence are for an alternative partition of a region, such as service areas. Interpolation to neighbourhoods uses a kernel method extended to take account of two types

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This paper considers estimation of disease prevalence for small areas (neighbourhoods) when the available observations on prevalence are for an alternative partition of a region, such as service areas. Interpolation to neighbourhoods uses a kernel method extended to take account of two types of collateral information. The first is morbidity and service use data, such as hospital admissions, observed for neighbourhoods. Variations in morbidity and service use are expected to reflect prevalence. The second type of collateral information is ecological risk factors (e.g., pollution indices) that are expected to explain variability in prevalence in service areas, but are typically observed only for neighbourhoods. An application involves estimating neighbourhood asthma prevalence in a London health region involving 562 neighbourhoods and 189 service (primary care) areas. Full article

(This article belongs to the Special Issue Spatial Epidemiology)

Open AccessArticle Synthesis of Microspherical LiFePO₄-Carbon Composites for Lithium-Ion Batteries

by Linghui Yu, Dandan Cai, Haihui Wang and Maria-Magdalena Titirici

Nanomaterials 2013, 3(3), 443-452; doi:10.3390/nano3030443

Received: 27 June 2013 / Revised: 16 July 2013 / Accepted: 17 July 2013 / Published: 22 July 2013

Abstract

This paper reports an “all in one” procedure to produce mesoporous, micro-spherical LiFePO₄ composed of agglomerated crystalline nanoparticles. Each nanoparticle is individually coated with a thin glucose-derived carbon layer. The main advantage of the as-synthesized materials is their good performance at high

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This paper reports an “all in one” procedure to produce mesoporous, micro-spherical LiFePO₄ composed of agglomerated crystalline nanoparticles. Each nanoparticle is individually coated with a thin glucose-derived carbon layer. The main advantage of the as-synthesized materials is their good performance at high charge-discharge rates. The nanoparticles and the mesoporosity guarantee a short bulk diffusion distance for both lithium ions and electrons, as well as additional active sites for the charge transfer reactions. At the same time, the thin interconnected carbon coating provides a conductive framework capable of delivering electrons to the nanostructured LiFePO₄. Full article

(This article belongs to the Special Issue Nanomaterials in Energy Conversion and Storage)

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Open AccessArticle Chelator-Accelerated One-Pot ‘Click’ Labeling of Small Molecule Tracers with 2-[¹⁸F]Fluoroethyl Azide

by Eva Galante, Bent Wilhelm Schoultz, Matthias Koepp and Erik Årstad

Molecules 2013, 18(5), 5335-5347; doi:10.3390/molecules18055335

Received: 8 April 2013 / Revised: 16 April 2013 / Accepted: 3 May 2013 / Published: 10 May 2013

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Abstract

2-[¹⁸F]Fluoroethyl azide ([¹⁸F]FEA) can readily be obtained by nucleophilic substitution of 2-azidoethyl-4-toluenesulfonate with [¹⁸F]fluoride (half-life 110 min), and has become widely used as a reagent for ‘click’ labeling of PET tracers. However, distillation of [¹⁸F]FEA

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2-[¹⁸F]Fluoroethyl azide ([¹⁸F]FEA) can readily be obtained by nucleophilic substitution of 2-azidoethyl-4-toluenesulfonate with [¹⁸F]fluoride (half-life 110 min), and has become widely used as a reagent for ‘click’ labeling of PET tracers. However, distillation of [¹⁸F]FEA is typically required, which is time-consuming and unpractical for routine applications. In addition, copper(I)-catalyzed cycloaddition of [¹⁸F]FEA with non-activated alkynes, and with substrates containing labile functional groups, can be challenging. Herein, we report a highly efficient and practical ligand-accelerated one-pot/two-step method for ‘click’ labeling of small molecule tracers with [¹⁸F]FEA. The method exploits the ability of the copper(I) ligand bathophenanthrolinedisulfonate to accelerate the rate of the cycloaddition reaction. As a result, alkynes can be added directly to the crude reaction mixture containing [¹⁸F]FEA, and as cyclisation occurs almost immediately at room temperature, the reaction is tolerant to labile functional groups. The method was demonstrated by reacting [¹⁸F]FEA with a series of alkyne-functionalized 6-halopurines to give the corresponding triazoles in 55–76% analytical radiochemical yield. Full article

(This article belongs to the Special Issue PET Chemistry in Molecular Imaging)

Open AccessArticle Drama & Demigods: Kingship and Charisma in Shakespeare’s England

by Kristin M.S. Bezio

Religions 2013, 4(1), 30-50; doi:10.3390/rel4010030

Received: 3 December 2012 / Revised: 17 January 2013 / Accepted: 18 January 2013 / Published: 22 January 2013

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Abstract

Shakespearean charisma, with its medieval roots in both religion and politics, served as a precursor to Max Weber’s later understanding of the term. The on-stage portrayal of charismatic kingship in the twilight of the Tudor dynasty was not coincidental; facing the imminent death

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Shakespearean charisma, with its medieval roots in both religion and politics, served as a precursor to Max Weber’s later understanding of the term. The on-stage portrayal of charismatic kingship in the twilight of the Tudor dynasty was not coincidental; facing the imminent death of a queen, the English nation was concerned about the future of the monarchy. Through the depiction of the production and deterioration of royal charisma, Shakespeare presents the anxiety of a population aware of the latent dangers of charismatic authority; while Elizabeth managed to perpetuate an unprecedented degree of long-term charismatic rule, there could be no certainty that her successor would be similarly capable. Shakespeare’s second tetralogy — known as the Henriad — examines this royal charisma as it appears both under crisis and in the process of what Weber would later characterize as routinization. While Henry IV (Bolingbroke) originally makes use of charisma to ensure his succession to Richard II’s throne, he loses his charismatic authority in the process. Henry V, by contrast, makes use of deliberate crisis — his claim to the French crown — in order to restore royal charisma. Henry V’s success, however, cannot last, and his son’s reign is a disastrous reminder that charisma is, as Weber will later argue, inherently unstable. Full article

(This article belongs to the Special Issue Charisma, Medieval and Modern) Printed Edition available

Open AccessArticle Assessing the Impact of Socioeconomic Variables on Small Area Variations in Suicide Outcomes in England

by Peter Congdon

Int. J. Environ. Res. Public Health 2013, 10(1), 158-177; doi:10.3390/ijerph10010158

Received: 23 October 2012 / Revised: 14 December 2012 / Accepted: 20 December 2012 / Published: 27 December 2012

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Abstract

Ecological studies of suicide and self-harm have established the importance of area variables (e.g., deprivation, social fragmentation) in explaining variations in suicide risk. However, there are likely to be unobserved influences on risk, typically spatially clustered, which can be modeled as random effects.

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Ecological studies of suicide and self-harm have established the importance of area variables (e.g., deprivation, social fragmentation) in explaining variations in suicide risk. However, there are likely to be unobserved influences on risk, typically spatially clustered, which can be modeled as random effects. Regression impacts may be biased if no account is taken of spatially structured influences on risk. Furthermore a default assumption of linear effects of area variables may also misstate or understate their impact. This paper considers variations in suicide outcomes for small areas across England, and investigates the impact on them of area socio-economic variables, while also investigating potential nonlinearity in their impact and allowing for spatially clustered unobserved factors. The outcomes are self-harm hospitalisations and suicide mortality over 6,781 Middle Level Super Output Areas. Full article

(This article belongs to the Special Issue Social and Economical Determinants of Health)

Open AccessArticle Unconventional Cadherin Localization in Honey Bee Gonads Revealed Through Domain-Specific Apis mellifera E- and N-Cadherin Antibodies Indicates Alternative Functions

by Mônica M. Florecki and Klaus Hartfelder

Insects 2012, 3(4), 1200-1219; doi:10.3390/insects3041200

Received: 13 August 2012 / Revised: 2 November 2012 / Accepted: 6 November 2012 / Published: 22 November 2012

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Abstract

As key factors in intercellular adhesion processes, cadherins play important roles in a plethora of developmental processes, including gametogenesis. In a previous study on cadherin localization in the gonads of honey bees, performed with heterologous pan-cadherin antibodies, we detected these proteins as (i)

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As key factors in intercellular adhesion processes, cadherins play important roles in a plethora of developmental processes, including gametogenesis. In a previous study on cadherin localization in the gonads of honey bees, performed with heterologous pan-cadherin antibodies, we detected these proteins as (i) associated with cell membranes, (ii) as homogeneously distributed throughout the cytoplasm, and (iii) as nuclear foci in both somatic and germline cells, raising the possibility of alternative functions. To further investigate such unusual intracellular cadherin localization we produced specific antibodies against the N- and C-terminal domains of honey bee N- and E-cadherin. A 160 kDa protein was recognized by the E-cadherin antibodies as well as one of approximately 300 kDa from those raised against N-cadherin. In gonad preparations, both proteins were detected as dispersed throughout the cytoplasm and as nuclear foci in both germline and somatic cells of queen and worker ovarioles, as well as in the testioles of drones. This leads us to infer that cadherins may indeed be involved in certain signaling pathways and/or transcriptional regulation during gametogenesis. In late oogenesis stages, immunolabeling for both proteins was observed at the cell cortex, in conformity with a role in cell adhesion. In testioles, E-cadherin was seen in co-localization with fusomes, indicating a possible role in cyst organization. Taken together, the distribution of N- and E-cadherins in honey bee gonads is suggestive of alternative roles for cadherins in gametogenesis of both sexes. Full article

(This article belongs to the Special Issue Honey Bee)

Open AccessArticle A Free Energy Principle for Biological Systems

by Friston Karl

Entropy 2012, 14(11), 2100-2121; doi:10.3390/e14112100

Received: 17 August 2012 / Revised: 1 October 2012 / Accepted: 25 October 2012 / Published: 31 October 2012

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Abstract

This paper describes a free energy principle that tries to explain the ability of biological systems to resist a natural tendency to disorder. It appeals to circular causality of the sort found in synergetic formulations of self-organization (e.g., the slaving principle) and models

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This paper describes a free energy principle that tries to explain the ability of biological systems to resist a natural tendency to disorder. It appeals to circular causality of the sort found in synergetic formulations of self-organization (e.g., the slaving principle) and models of coupled dynamical systems, using nonlinear Fokker Planck equations. Here, circular causality is induced by separating the states of a random dynamical system into external and internal states, where external states are subject to random fluctuations and internal states are not. This reduces the problem to finding some (deterministic) dynamics of the internal states that ensure the system visits a limited number of external states; in other words, the measure of its (random) attracting set, or the Shannon entropy of the external states is small. We motivate a solution using a principle of least action based on variational free energy (from statistical physics) and establish the conditions under which it is formally equivalent to the information bottleneck method. This approach has proved useful in understanding the functional architecture of the brain. The generality of variational free energy minimisation and corresponding information theoretic formulations may speak to interesting applications beyond the neurosciences; e.g., in molecular or evolutionary biology. Full article

(This article belongs to the Special Issue The Information Bottleneck Method)

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Open AccessArticle Molecular Identification of Chronic Bee Paralysis Virus Infection in Apis mellifera Colonies in Japan

by Tomomi Morimoto, Yuriko Kojima, Mikio Yoshiyama, Kiyoshi Kimura, Bu Yang and Tatsuhiko Kadowaki

Viruses 2012, 4(7), 1093-1103; doi:10.3390/v4071093

Received: 7 June 2012 / Revised: 15 June 2012 / Accepted: 23 June 2012 / Published: 29 June 2012

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Abstract

Chronic bee paralysis virus (CBPV) infection causes chronic paralysis and loss of workers in honey bee colonies around the world. Although CBPV shows a worldwide distribution, it had not been molecularly detected in Japan. Our investigation of Apis mellifera and Apis cerana japonica

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Chronic bee paralysis virus (CBPV) infection causes chronic paralysis and loss of workers in honey bee colonies around the world. Although CBPV shows a worldwide distribution, it had not been molecularly detected in Japan. Our investigation of Apis mellifera and Apis cerana japonica colonies with RT-PCR has revealed CBPV infection in A. mellifera but not A. c. japonica colonies in Japan. The prevalence of CBPV is low compared with that of other viruses: deformed wing virus (DWV), black queen cell virus (BQCV), Israel acute paralysis virus (IAPV), and sac brood virus (SBV), previously reported in Japan. Because of its low prevalence (5.6%) in A. mellifera colonies, the incidence of colony losses by CBPV infection must be sporadic in Japan. The presence of the (−) strand RNA in dying workers suggests that CBPV infection and replication may contribute to their symptoms. Phylogenetic analysis demonstrates a geographic separation of Japanese isolates from European, Uruguayan, and mainland US isolates. The lack of major exchange of honey bees between Europe/mainland US and Japan for the recent 26 years (1985–2010) may have resulted in the geographic separation of Japanese CBPV isolates. Full article

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Open AccessArticle Neotenic Phenotype and Sex Ratios Provide Insight into Developmental Pathways in Reticulitermes flavipes (Isoptera: Rhinotermitidae)

by Jian Hu and Brian T. Forschler

Insects 2012, 3(2), 538-552; doi:10.3390/insects3020538

Received: 16 April 2012 / Revised: 13 May 2012 / Accepted: 14 May 2012 / Published: 4 June 2012

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Abstract

Several thousand Reticulitermes flavipes (Kollar) including worker, nymph, soldier, neotenic and alate castes were collected from three pine logs brought into the laboratory on dates five years apart. The neotenics, all nymphoid, were divided into three groups based on the extent of cuticle

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Several thousand Reticulitermes flavipes (Kollar) including worker, nymph, soldier, neotenic and alate castes were collected from three pine logs brought into the laboratory on dates five years apart. The neotenics, all nymphoid, were divided into three groups based on the extent of cuticle pigmentation and termed regular neotenics (RN), black-headed neotenics (BHN) or black neotenics (BN). All castes, from Log A, in 2008, provided a neutral sex ratio except BHN (N = 378) and BN (N = 51) which were exclusively male while the soldiers (N = 466) were female-biased. This information suggests that there is a sex-linked bifurcation along the path for termite development with a male-biased neotenic or female-biased soldier as the choice. In contrast, termites collected in 2004 from Log B provided sex ratios that included a female biased RN (N = 1017), a neutral soldier (N = 258) and male biased BHN (N = 99) and workers (N = 54). Log C, collected in 2009, provided female biased soldiers (N = 32), RNs (N = 18) and BHNs (N = 4) and only male BN (N = 5). Eight laboratory cultures, ranging in age from five to 14 years old, also were sampled and all castes sexed. The census included a 14-year old queen-right colony, an 8-year old polyandrous colony and six colonies provided nymphs and male-biased worker populations. Together these data indicate a flexible caste determination system providing a unique opportunity for a better understanding of the flexible developmental options available in R. flavipes that we discuss relative to the literature on Reticulitermes ontogeny. Full article

(This article belongs to the Special Issue Feature Papers 2012)

Open AccessArticle Primary Prevention of Lead Exposure—Blood Lead Results at Age Two Years

by Carla Campbell, Edward Gracely, Mary Tran, Naomi Starkey, Hans Kersten, Peter Palermo, Nancy Rothman, Laura Line and Tine Hansen-Turton

Int. J. Environ. Res. Public Health 2012, 9(4), 1216-1226; doi:10.3390/ijerph9041216

Received: 14 March 2012 / Revised: 30 March 2012 / Accepted: 5 April 2012 / Published: 11 April 2012

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Abstract

Objectives: The Philadelphia Lead Safe Homes (LSH) Study was designed to evaluate whether educational and environmental interventions in the first year of life for families of newborns increased knowledge of lead exposure prevention and were associated with less elevation of blood lead

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Objectives: The Philadelphia Lead Safe Homes (LSH) Study was designed to evaluate whether educational and environmental interventions in the first year of life for families of newborns increased knowledge of lead exposure prevention and were associated with less elevation of blood lead levels (BLLs) for these children, when compared to children receiving standard care. Methods: The current study performed descriptive statistics on the second-year BLL data for both groups and compared these using chi-square tests for proportions and unpaired t-tests for means. Results: A BLL result was found for 159 (50.6%) of the 314 LSH cohort children and 331 (52.7%) of the 628 control children (p = 0.1). Mean and standard deviation for age at draw was 23.8 (3.4) months versus 23.6 (3.1) months (P = 0.6). Geometric mean BLLs were 3.7 versus 3.5 µg/dL (P = 0.4). The percentages of the cohort group with a BLL of ≥20, ≥10 and ≥5 μg/dL, respectively, were 0.6%, 5% and 30%; for the controls 1.2%, 6.6%, and 25%. These percentages were not significantly different between groups. Conclusion: A comparison of geometric mean BLLs and percentages above several BLL cut points drawn at age two years in a group of urban newborns benefitting from study interventions versus a group of similar urban children did not yield statistically significant differences. Both groups had relatively lower lead levels when compared to historical cohort groups, which may reflect a continuing downward trend in BLLs in U.S. children. The interventions did result in benefits to the families such as an increase in parental knowledge about lead exposure prevention and in-home wet cleaning activity, and a decrease in lead dust levels in study homes. Full article

(This article belongs to the Special Issue Maternal and Child Health)

Open AccessProduct Review A Preliminary Study on Elimination of Colonies of the Mound Building Termite Macrotermes gilvus (Hagen) Using a Chlorfluazuron Termite Bait in the Philippines

by Partho Dhang

Insects 2011, 2(4), 486-490; doi:10.3390/insects2040486

Received: 25 August 2011 / Revised: 1 November 2011 / Accepted: 2 November 2011 / Published: 10 November 2011

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Abstract

The effectiveness of a chlorfluazuron termite bait in eliminating colonies of the termite species Macrotermes gilvus (Hagen) was evaluated under field conditions. Three active termite mounds were chosen for this study, two acted as test mounds and the other as the control. Four

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The effectiveness of a chlorfluazuron termite bait in eliminating colonies of the termite species Macrotermes gilvus (Hagen) was evaluated under field conditions. Three active termite mounds were chosen for this study, two acted as test mounds and the other as the control. Four In-Ground Stations (IGS) were installed around each mound. Interception occurred almost immediately in all the stations, which were subsequently baited. The control mound was fed a bait matrix lacking the active ingredient. Stations were re-baited every 2 weeks for 10–12 weeks until bait consumption ceased in the test mounds. The mounds were left undisturbed for four more weeks before being destructively sampled. The desiccated remains of workers, soldiers, late instars and queen were found upon sampling the treated mounds. A few live termites were located in one treated mound but were darkly pigmented indicating bait consumption. The control mound remained healthy and did not show any visible sign of negative impact. The bait successfully suppressed or eliminated both M. gilvus colonies within 16 weeks from commencement of feeding. Full article

(This article belongs to the Special Issue Termite Management and Control - Special Issue Dedicated in Memory of Dr. Kunio Tsunoda)

Open AccessArticle Deriving Fuel Mass by Size Class in Douglas-fir (Pseudotsuga menziesii) Using Terrestrial Laser Scanning

by Carl Seielstad, Crystal Stonesifer, Eric Rowell and Lloyd Queen

Remote Sens. 2011, 3(8), 1691-1709; doi:10.3390/rs3081691

Received: 1 July 2011 / Revised: 26 July 2011 / Accepted: 4 August 2011 / Published: 16 August 2011

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Abstract

Requirements for describing coniferous forests are changing in response to wildfire concerns, bio-energy needs, and climate change interests. At the same time, technology advancements are transforming how forest properties can be measured. Terrestrial Laser Scanning (TLS) is yielding promising results for measuring tree

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Requirements for describing coniferous forests are changing in response to wildfire concerns, bio-energy needs, and climate change interests. At the same time, technology advancements are transforming how forest properties can be measured. Terrestrial Laser Scanning (TLS) is yielding promising results for measuring tree biomass parameters that, historically, have required costly destructive sampling and resulted in small sample sizes. Here we investigate whether TLS intensity data can be used to distinguish foliage and small branches (≤0.635 cm diameter; coincident with the one-hour timelag fuel size class) from larger branchwood (>0.635 cm) in Douglas-fir (Pseudotsuga menziesii) branch specimens. We also consider the use of laser density for predicting biomass by size class. Measurements are addressed across multiple ranges and scan angles. Results show TLS capable of distinguishing fine fuels from branches at a threshold of one standard deviation above mean intensity. Additionally, the relationship between return density and biomass is linear by fuel type for fine fuels (r² = 0.898; SE 22.7%) and branchwood (r² = 0.937; SE 28.9%), as well as for total mass (r² = 0.940; SE 25.5%). Intensity decays predictably as scan distances increase; however, the range-intensity relationship is best described by an exponential model rather than 1/d². Scan angle appears to have no systematic effect on fine fuel discrimination, while some differences are observed in density-mass relationships with changing angles due to shadowing. Full article

(This article belongs to the Special Issue Laser Scanning in Forests)

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Open AccessArticle A Multilevel Model for Comorbid Outcomes: Obesity and Diabetes in the US

by Peter Congdon

Int. J. Environ. Res. Public Health 2010, 7(2), 333-352; doi:10.3390/ijerph7020333

Received: 16 November 2009 / Accepted: 21 January 2010 / Published: 27 January 2010

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Abstract

Multilevel models are overwhelmingly applied to single health outcomes, but when two or more health conditions are closely related, it is important that contextual variation in their joint prevalence (e.g., variations over different geographic settings) is considered. A multinomial multilevel logit regression approach

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Multilevel models are overwhelmingly applied to single health outcomes, but when two or more health conditions are closely related, it is important that contextual variation in their joint prevalence (e.g., variations over different geographic settings) is considered. A multinomial multilevel logit regression approach for analysing joint prevalence is proposed here that includes subject level risk factors (e.g., age, race, education) while also taking account of geographic context. Data from a US population health survey (the 2007 Behavioral Risk Factor Surveillance System or BRFSS) are used to illustrate the method, with a six category multinomial outcome defined by diabetic status and weight category (obese, overweight, normal). The influence of geographic context is partly represented by known geographic variables (e.g., county poverty), and partly by a model for latent area influences. In particular, a shared latent variable (common factor) approach is proposed to measure the impact of unobserved area influences on joint weight and diabetes status, with the latent variable being spatially structured to reflect geographic clustering in risk. Full article

(This article belongs to the Special Issue Advances in Epidemiology)

Open AccessArticle Estimating Prevalence of Coronary Heart Disease for Small Areas Using Collateral Indicators of Morbidity

by Peter Congdon

Int. J. Environ. Res. Public Health 2010, 7(1), 164-177; doi:10.3390/ijerph7010164

Received: 20 November 2009 / Accepted: 14 January 2010 / Published: 18 January 2010

Cited by 5 | Viewed by 6718 | PDF Full-text (1328 KB) | HTML Full-text | XML Full-text

Abstract

Different indicators of morbidity for chronic disease may not necessarily be available at a disaggregated spatial scale (e.g., for small areas with populations under 10 thousand). Instead certain indicators may only be available at a more highly aggregated spatial scale; for example, deaths

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Different indicators of morbidity for chronic disease may not necessarily be available at a disaggregated spatial scale (e.g., for small areas with populations under 10 thousand). Instead certain indicators may only be available at a more highly aggregated spatial scale; for example, deaths may be recorded for small areas, but disease prevalence only at a considerably higher spatial scale. Nevertheless prevalence estimates at small area level are important for assessing health need. An instance is provided by England where deaths and hospital admissions for coronary heart disease are available for small areas known as wards, but prevalence is only available for relatively large health authority areas. To estimate CHD prevalence at small area level in such a situation, a shared random effect method is proposed that pools information regarding spatial morbidity contrasts over different indicators (deaths, hospitalizations, prevalence). The shared random effect approach also incorporates differences between small areas in known risk factors (e.g., income, ethnic structure). A Poisson-multinomial equivalence may be used to ensure small area prevalence estimates sum to the known higher area total. An illustration is provided by data for London using hospital admissions and CHD deaths at ward level, together with CHD prevalence totals for considerably larger local health authority areas. The shared random effect involved a spatially correlated common factor, that accounts for clustering in latent risk factors, and also provides a summary measure of small area CHD morbidity. Full article

(This article belongs to the Special Issue Cardiovascular Diseases and Public Health)

Open AccessArticle Maximum Entropy Estimation of Transition Probabilities of Reversible Markov Chains

by Erik Van der Straeten

Entropy 2009, 11(4), 867-887; doi:10.3390/e11040867

Received: 21 September 2009 / Accepted: 10 November 2009 / Published: 17 November 2009

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Abstract

In this paper, we develop a general theory for the estimation of the transition probabilities of reversible Markov chains using the maximum entropy principle. A broad range of physical models can be studied within this approach. We use one-dimensional classical spin systems to

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In this paper, we develop a general theory for the estimation of the transition probabilities of reversible Markov chains using the maximum entropy principle. A broad range of physical models can be studied within this approach. We use one-dimensional classical spin systems to illustrate the theoretical ideas. The examples studied in this paper are: the Ising model, the Potts model and the Blume-Emery-Griffiths model. Full article

(This article belongs to the Special Issue Maximum Entropy)

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