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This chapter interrogates assumptions behind the models used both in cost-effectiveness analysis, and to set global targets. The models neglected to address how human rights realities, such as health sector discrimination and legal barriers, might undermine the optimistic scenarios the models predicted would result from scale-up of testing and treatment. The lack of quantitative research showing that addressing human rights would have a measurable impact on health, and that such work was cost-effective, meant that it was easy to exclude these and similarly unquantified considerations from biomedical scael-up. Thus in many countries, the work of addressing stigma, discrimination, criminalization, and gender inequality, while frequently cited as rhetorically important, is in practice an afterthought in planning, financing and implementing the HIV response. The second part of the chapter returns to Grenada to observe community activists and health officials wrestling with the challenges of quantification, as they debate which questions to ask in the study. While the global mathematical models aimed at simplicity in order to drive decision-makers to prioritize funding HIV programs, the CVC study wrestled with the problem of how best to capture local complexities and protect the fragile thread of trust they were beginning to establish with hidden communities.
Each individual in the population has a distinct maximum growth potential, and the growth curve may vary depending on the response to nutrient intake, growth phase and variability among animals. The present study aimed to (1) model weight gain (WG) response to methionine+cystine (Met+Cys) supply using different mathematical functions, (2) identify functions that better fit the growth responses of pullets, (3) determine the Met+Cys requirements that maximize WG based on breeding standards and (4) partition the Met+Cys requirements for WG and maintenance. Three trials were performed using 1448 laying-type pullets. We adopted a completely randomized design with eight treatments and six replicates. The first trial (2 to 6 weeks, P1) used 15 pullets per experimental unit. The second and third trials (8 to 12 weeks, P2; 14 to 18 weeks, P3) were used eight pullets per replicate. The Met+Cys levels were obtained using a dilution technique. The mathematical functions used to describe WG responses to Met+Cys intake were broken line, broken line with curvilinear ascendancy, Michaelis–Menten, saturation kinetics and three logistic and three exponential models. Models were selected using the Bayesian information criterion and evaluated by residual analysis. It was possible to model the responses using the studied functions. The best functions were obtained by logistic and sigmoidal models in P1 and P2, and with the broken line by the curvilinear ascendancy model in P3. The Met+Cys intake that determined the maximum potential for WG (WGmax) in P1, P2 and P3 were 313, 381 and 318 mg/day, respectively. The Met+Cys requirements for WG were 20, 22 and 27 mg/g, and for maintenance were 214, 53 and 30 mg/kgBW0.75 for P1, P2 and P3, respectively.
I review the hypothesis that neither space nor quantum mechanics is fundamental, and both are emergent from a more fundamental description that is neither. This fundamental description is a completion of quantum mechanics based on relational hidden variables. Here, relational means that they give a fuller description, not of an individual particle but of a network of relations among particles. This completion of quantum mechanics does not live in space, rather space is an emergent description of an underlying network of relations. Since locality is, in this sense, emergent, locality can be disordered, and one of the effects of this is quantum nonlocality. This summarizes a line of thought that weaves through many of my papers on quantum foundations, from the early 1980s to the present.
Non-destructive means for estimating Dioscorea bulbifera biomass will help gauge its management efficacy over time. Herein, we developed allometric equations to estimate total and fractional biomass components, and densities of aerial bulbils and underground tubers of field grown Dioscorea bulbifera in Florida. We selected four naturally infested sites representing its southern, central, and northern distribution in Florida and measured three independent variables (vine densities, stem diameters, and top heights) of 84 (21 site-1) discrete D. bulbifera patches during late October-early December of 2012. We destructively harvested D. bulbifera biomass, sorted by tubers, stems, leaves and bulbils, counted units of bulbils and underground tubers (dependent variables) and dried to a constant weight. Mean percentages of tuber, stem, leaf, and bulbil fractions in total biomass were 42.0, 15.6, 26.0 and 16.4, respectively. We developed parameterized multiplicative prediction models and regression equations for each dependent variable. Slopes of relationships among independent and dependent variables varied by biomass and density (bulbil and tuber) of plant components. Multiplied values of independent variables: all three for total, tuber, stem and leaf biomass; two (vine-base diameter*patch height) for bulbil biomass; and two (vine density*patch height) for bulbil density; and only one (stem density) for tuber-density provided best (R2 based) prediction values. These models will provide non-destructive methods for estimating biomass components and density of vegetative propagules of naturally growing D. bulbifera. Models are critical for understanding the performance of D. bulbifera in its exotic range, estimating biomass to project control costs, and comparing biomass components and bulbil/tuber densities during pre- and post-management periods to gauge control efficacy.
Loop quantum gravity has formalized a robust scheme in resolving classical singularities in a variety of symmetry-reduced models of gravity. In this essay, we demonstrate that the same quantum correction that is crucial for singularity resolution is also responsible for the phenomenon of signature change in these models, whereby one effectively transitions from a `fuzzy' Euclidean space to a Lorentzian space-time in deep quantum regimes. As long as one uses a quantization scheme that respects covariance, holonomy corrections from loop quantum gravity generically leads to nonsingular signature change, thereby giving an emergent notion of time in the theory. Robustness of this mechanism is established by comparison across a large class of midisuperspace models and allowing for diverse quantization ambiguities. Conceptual and mathematical consequences of such an underlying quantum-deformed spacetime are briefly discussed.
To measure the role of water, sanitation and hygiene (WASH) practices on recovery from stunting and assess the role of timing of stunting on the reversal of this phenomenon
Data from the MAL-ED multi-country birth cohort study was used for the current analysis. Generalised linear mixed-effects models were used to estimate the probability of reversal of stunting with WASH practice and timing of stunting as the exposures of interest.
Seven different countries across three continents.
A total of 612 children <2 years of age.
We found that not WASH practice but timing of stunting had statistically significant association with recovery from stunting. In comparison with the children who were stunted at 6 months, children who were stunted at 12 months had 1·9 times (β = 0·63, P = 0·03) more chance of recovery at 24 months of age. And, children who were stunted at 18 months of age even had higher odds (adjusted OR = 3·01, β = 1·10, P < 0·001) of recovery than children who were stunted at 6 months. Additionally, mother’s height (β = 0·59, P = 0·04) and household income (β = 0·02, P < 0·05) showed statistically significant associations with the outcome.
The study provided evidence for the role of timing of stunting on the recovery from the phenomenon. This novel finding indicates that the programmes to promote linear growth should be directed at the earliest possible timepoints in the course of life.
Huencú Nazar es un sitio arqueológico a cielo abierto localizado en el Sistema Lagunar Hinojo-Las Tunas (región pampeana, Argentina) que fue ocupado durante el Holoceno tardío (ca. 3000 aP). En un área de 5.000 m2 se distribuyen 22 fogones, escondrijos de roca y concentraciones de rocas granitoides. En uno de los sectores excavados se registraron fogones en cubeta y el uso de huesos de Lama guanicoe (Artiodactyla, Camelidae) como combustible. El uso de combustible óseo permitió solucionar el problema de los residuos molestos para la comodidad de las personas ubicadas alrededor de los fogones. En torno a las estructuras de combustión se depositaron materiales relacionados con la subsistencia y la tecnología.
Regression modelling involving heavy-tailed response distributions, which have heavier tails than the exponential distribution, has become increasingly popular in many insurance settings including non-life insurance. Mixed Exponential models can be considered as a natural choice for the distribution of heavy-tailed claim sizes since their tails are not exponentially bounded. This paper is concerned with introducing a general family of mixed Exponential regression models with varying dispersion which can efficiently capture the tail behaviour of losses. Our main achievement is that we present an Expectation-Maximization (EM)-type algorithm which can facilitate maximum likelihood (ML) estimation for our class of mixed Exponential models which allows for regression specifications for both the mean and dispersion parameters. Finally, a real data application based on motor insurance data is given to illustrate the versatility of the proposed EM-type algorithm.
This commentary presents some reflections on the peculiar position obsessive-compulsive personality disorder (OCPD) has among Cluster C PDs. Based on epidemiological, factor-analytic, and cognitive considerations, it is argued that OCPD deviates from avoidant and dependent PD. First, epidemiological research shows that in the general population OCPD is not associated with markers of poor functioning and unfortunate living circumstances. On the contrary, positive associations between OCPD and such markers are found. Moreover, disproportionally few people with OCPD seek mental health care. Second, based on a second-order factor analysis on a large data set that confirms the cluster structure in PDs, it is argued that OCPD has a deviant position, relatively weakly loading on the cluster-C factor. Third, research on cognitive processes and structures in PDs indicates that OCPD deviates from avoidant and dependent PD in several ways, including sharing an interpretation style with nonpatients, and in not reporting vulnerable cognitive-emotional states. Dysfunctional cognitive characteristics might be pushed out of awareness by powerful overcompensatory strategies that are more characteristic for Cluster B than for Cluster C. Alternatively, OCPD is characterized more by deviant cognitive processes than by specific content of schemas. OCPD’s dysfunctional core should be clarified.
Mild cognitive impairment (MCI), as a stage in the cognitive continuum between normal ageing and dementia, is mainly characterized by memory impairment. The aims of this study were to examine CANTAB measures of temporal changes of visual memory in MCI and to evaluate the usefulness of the baseline scores for predicting changes in cognitive status.
The study included 201 participants aged over 50 years with subjective cognitive complaints. Visual memory was assessed with four CANTAB tests [paired associates learning (PAL), delayed matching to sample (DMS), pattern recognition memory (PRM) and spatial span (SSP)] administered at baseline and on two further occasions, with a follow-up interval of 18–24 months. Participants were divided into three groups according to the change in their cognitive status: participants with subjective cognitive complaints who remained stable, MCI participants who remained stable (MCI-Stable) and MCI participants whose cognitive deterioration continued (MCI-Worsened). Linear mixed models were used to model longitudinal changes, with evaluation time as a fixed variable, and multinomial regression models were used to predict changes in cognitive status.
Isolated significant effects were obtained for age and group with all CANTAB tests used. Interactions between evaluation time and group were identified in the PAL and DMS tests, indicating different temporal patterns depending on the changes in cognitive status. Regression models also indicated that CANTAB scores were good predictors of changes in cognitive status.
Decline in visual memory measured by PAL and DMS tests can successfully distinguish different types of MCI, and considered together PAL, DMS, PRM and SSP can predict changes in cognitive status.
Diagnostic reliability receives cursory attention in the literature with wide ranges of kappa coefficients often interpreted as “adequate.” Moreover, the vast majority of personality disorder (PD) kappa estimates, including those reviewed by Flory (this chapter), are derived from the audio/video recording method. This method results in inflated estimates of diagnostic reliability, which provides limited insight into whether patients would receive the same diagnosis at different hospitals or clinics and whether researchers are studying similar patients. A more rigorous and ecologically valid method for assessing diagnostic reliability is the test-retest method. Although echoing some of Flory’s points, the authors here disagree with her assertion that categorical PDs demonstrate acceptable reliability. In fact, the reliability of categorical PDs assessed using the test-retest method is far lower than the DSM-5 conceptualization would indicate. Moreover, the test-retest diagnostic reliability of categorical PDs fails to achieve minimal benchmarks established in the “normal” personality literature, indicating critical problems for the DSM-5 categorical model. If the goal is to provide optimal patient care and advance clinical science, then adopting the trait-based dimensional model of personality pathology from section III of DSM-5 is necessary.
In our rejoinder to the excellent commentaries provided by Macfie, Noose, and Gorrondona (This Volume) and Davies and Thompson (This Volume), we discuss three key directions for research and clinical work that emerge from our chapter on environmental and sociocultural influences on personality disorders. First, it is critical to recognize the importance of early caregiving environments and family processes in the etiology of personality pathology. Second, identifying transactional models that integrate biological, psychological and sociocultural influences may move the field towards a more holistic and multifaceted understanding of the underpinnings of personality pathology. Third and finally, expanding the use of dimensional models of personality pathology may contextualize these transactional relationships and facilitate more rapid advances in our understanding and conceptualizations of (mal)adaptive expressions of personality traits. Dimensional models may further facilitate consideration of socioeconomic, cultural and geopolitical influences in evaluating and defining the maladaptiveness of specific traits and behaviors. Increasing our focus on contextual, environmental, and sociocultural influences in research design, assessment, and case conceptualization will improve personality research and clinical care.
Animal models are critical for the study of mental disorders and their treatments but are repeatedly criticized for problems with validity and reproducibility. One approach to enhance validity and reproducibility of models is to use test batteries rather than single tests. Yet, a question regarding batteries is whether one can expect a consistent individual behavioral phenotype in mice across tests that can be presumed to be part of the same construct.
The present study was designed to explore the relationship between the behaviors of mice across tests in some variations of test batteries for depression- and anxiety-like behaviors.
Female and male healthy, intact and untreated mice from the ICR and black Swiss strains were used in four separate experiments. With some variations, mice were exposed to a battery of behavioral tests representing affective- and anxiety-like behaviors. Data were analyzed for differences between sexes and for correlations between behaviors within and across the tests in the battery.
No differences were found between the sexes. With very few exceptions, we found correlations within tests (when one test has more than one measure or is repeated) but not across different tests within the battery.
The results cast some doubt on the utility of behavioral test batteries to represent different facets of emotional behavior in healthy intact outbred mice, without any interventions or treatments. Additional studies are designed to explore whether stronger relationship between the tests will appear after manipulations or drug treatments.
Evans et al. (this volume) reviewed prominent dimensional measures of personality, discussed the clinical usefulness of these measures, and provided an overview of personality assessment issues. This commentary focuses on the clinical utility and applications of personality traits and assessment, as well as factors relevant to bridging the research-to-practice gap. In order to adequately disseminate and implement evidence-based personality assessments into practice, personality pathology researchers should be taking active steps to move the empirical base (e.g., validated models of personality, evidence-based assessments, aspects of clinical utility) into application. The process of translating these traits and measures into practice may include assessing barriers to use among practitioners, addressing matters of acceptability and feasibility, and providing training and consultation to practitioners. The authors review benefits of including adaptive traits in assessment and practice (e.g., assist with collaborative treatment planning, decrease stigma), provide commentary on the incremental utility of dysfunction including the use of external correlates, and outline the importance of bipolarity of dimensional trait measures.
Townsend’s model of attached eddies for boundary layers is revisited within a quasi-linear approximation. The velocity field is decomposed into a mean profile and fluctuations. While the mean is obtained from the nonlinear equations, the fluctuations are modelled by replacing the nonlinear self-interaction terms with an eddy-viscosity-based turbulent diffusion and stochastic forcing. Under this particular approximation, the resulting fluctuation equations remain linear, enabling solutions to be superposed, the same theoretical idea used in the original attached eddy model. By leveraging this feature, the stochastic forcing is determined self-consistently by solving an optimisation problem which minimises the difference between the Reynolds shear stresses from the mean and fluctuation equations, subject to a constraint that the averaged Reynolds shear-stress spectrum is sufficiently smooth in the spatial wavenumber space. The proposed quasi-linear approximation is subsequently applied to channel flow for Reynolds number
ranging from 500 to 20 000. The best result is obtained when the Reynolds stress is calculated by retaining only the two leading proper orthogonal decomposition modes, which further filters out the modelling artefact caused by the unphysical stochastic forcing. In this case, the resulting turbulence intensity profile and energy spectra exhibit the same qualitative behaviour as direct numerical simulation (DNS) data throughout the entire wall-normal domain, while reproducing the early theoretical predictions of the original attached eddy model within a controlled approximation to the Navier–Stokes equations. Finally, the proposed quasi-linear approximation reveals that the peak streamwise and spanwise turbulence intensities may deviate slightly from the logarithmic scaling with the Reynolds number for
, and the supporting evidence is presented using the existing DNS data.
In addition to identifying important biological and psychosocial correlates of personality disorders, recent research has illuminated environmental and sociocultural factors that influence the development, expression, and maintenance of personality disorders. In particular, cross-national and cross-cultural comparisons indicate that the expression, meaning, and impact of specific personality traits and behaviors differ across gender roles, historical periods, and cultural and socioeconomic groups. Moreover, whereas interpersonal and attachment theories have historically underscored the importance of parent-child relationships, emotional attunement, and early childhood adversity in the formation and continuation of personality pathology, recent behavioral genetic studies suggest that unique, non-shared environmental influences account for as much or more variance in personality disorders as shared influences among family members. Additional sources of sociocultural and environmental influence on personality disorders include peer and romantic relationships. Increasingly, integrative theories highlight the importance of considering interactions and transactions across biological, psychological, and sociocultural systems in understanding the etiology of personality disorders. These theoretical and empirical advances have important implications for personality disorder research and clinical practice, and point to the potential utility of considering cross-cultural diagnostic validity when evaluating dimensional or categorical diagnostic models.
In a thoughtful and scholarly review, Paris (this volume) considers a variety of challenges and controversies besetting the personality disorders field. The author of this commentary concurs with most of his arguments. However, he examines three unresolved conceptual challenges in the personality disorders field that are largely unmentioned by Paris: (1) the relation between general personality traits and personality pathology, along with the possibility that some personality disorders reflect maladaptive configurations (interactions) among these traits; (2) the distinction between basic tendencies and characteristic adaptations, along with the possibility that criterion sets for some personality disorders (e.g., borderline personality disorder) reflect complex admixtures of both; (3) the implications of recently developed network models of psychopathology for conceptualizing personality disorders. Aided by statistical advances, the personality disorders field has made impressive scientific progress in some respects, but it needs to invest more of its time and energy addressing foundational conceptual questions.
Mortality volatility is crucially important to many aspects of index-based longevity hedging, including instrument pricing, hedge calibration and hedge performance evaluation. This paper sets out to develop a deeper understanding of mortality volatility and its implications on index-based longevity hedging. First, we study the potential asymmetry in mortality volatility by considering a wide range of generalised autoregressive conditional heteroskedasticity (GARCH)-type models that permit the volatility of mortality improvement to respond differently to positive and negative mortality shocks. We then investigate how the asymmetry of mortality volatility may impact index-based longevity hedging solutions by developing an extended longevity Greeks framework, which encompasses longevity Greeks for a wider range of GARCH-type models, an improved version of longevity vega, and a new longevity Greek known as “dynamic Delta”. Our theoretical work is complemented by two real-data illustrations, the results of which suggest that the effectiveness of an index-based longevity hedge could be significantly impaired if the asymmetry in mortality volatility is not taken into account when the hedge is calibrated.
Intergenerational transfers measured in several currencies (e.g. co-residence, contact, proximity and support) have been always considered important indicators for family solidarity. Most of the studies on intergenerational transfers examine the structural characteristics of such exchanges (as distance, frequency, type, motives), emphasising the potential positive association between the structure and the quality of parent–child relationships. Additionally, while most surveys include questions on the structural indicators of family exchanges, it is still uncommon for them to contain assessments of the relationships between parents and their adult children as well. Using the Italian 2009 Family Survey, this study analyses the satisfaction of parent–child relationships for parents aged 65 and older. After examining the association of such a variable with the structural indicators of intergenerational exchanges (frequency of contact), we explored the individual factors associated with satisfaction of relationships with a child using multilevel multinomial models. Overall, older Italian parents report high satisfaction in their relationships with their adult children. Additionally, a not strong, but statistically significant association between structure (contact) and satisfaction was found. This study shows how high satisfaction of relationships with children is positively associated with being a mother and being married and negatively associated with bad health status. Some of the variables considered have different impacts between the sexes of parents. Additionally, a better appreciation of relationships with daughters compared to sons was found, especially for fathers.