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Stalking as paranoid attachment: a typological and dynamic model.

Stalking encompasses a wide range of behavioral patterns, risk factors, interpersonal dynamics, and dangerousness. To account for these diverse phenomena, we propose that stalking behavior is best conceptualized by a dynamic interaction of attachment styles and psychodynamic phenomena. This paper articulates a model that explains stalking behavior within the framework of attachment theory. Four prototypical configurations of stalkers and their victims are developed. Each configuration is discussed in terms of a pattern of internal representations, affective constellations, combinations of aggression and narcissism, and potential for future violence. The four configurations proposed here are maintained through stalkers' over ideational linkage fantasies and projective identifications, which range from shame-prone and needy idealization to malevolent torment of the victim. Our model arrays erotomanic, jealous, and persecutory attachments along a continuum of increasingly paranoid and pathological identifications. We argue that these prototypical attachment configurations provide a theoretically driven means of differentiating phases of stalking, and as such provide useful leads in the empirical study and clinical assessment, treatment, and management of stalkers.

Adult↗

Changes in repolarization dynamicity and the assessment of the arrhythmic risk.

At the present time, the assessment of the arrhythmic risk from surface ECG recordings is built on time-domain and frequent-domain analysis of high resolution ECG acquisition together with interlead variability of QT interval duration (QT dispersion). The corresponding raw ECG tracings are obtained in resting conditions. However, the dynamic aspects of the ECG signal is a rapidly evolving matter of interest. In addition to the beat-to-beat oscillations of the ventricular repolarization amplitude (QT alternans), there is growing evidence that the patterns of QT interval shortening with increasing heart rate are linked to susceptibility to ventricular arrhythmias. In this report, we will mainly address the association between QT dynamicity and the risk of developing torsades de pointes.

Anti-Arrhythmia Agents↗

High temporal resolution dynamic contrast MRI in a high risk group for placenta accreta.

Antenatal diagnosis of placenta accreta with MR is not easy even now because T2-weighted images (T2WI) cannot differentiate chorionic villi from decidua basalis. We performed dynamic contrast MRI to study whether trophoblastic villi could be separately demonstrated from the decidua basalis, and whether the contrast resolution between the placenta and myometrium could improve compared to T2WI. Six pregnant women with prior cesarean section were examined at 34-38 gestational weeks. Sagittal T2-weighted images with fast spin echo sequences and dynamic contrast studies with fast field echo sequence every 10-14 s after contrast injection were performed. We analyzed the enhancing pattern of the placenta and compared the contrast between placenta and myometrium. We reviewed medical records to identify complications during the placental delivery and the complications of their newborns. In the early phase after contrast enhancement, multiple foci of the strong lobular enhancement were observed in all cases. Other parts of placenta were slowly but strongly enhanced following them. We speculated that the former corresponded to intervillous space and the latter decidua basalis. The contrast between placenta and myometrium tended to be distinct near the inner cervical os on both T2WI and dynamic contrast study. On the other hand, it was indistinct in the upper part of the uterine body on T2WI despite it was clearly demonstrated on dynamic contrast study. The placentae were delivered without any complication in all cases. Although two neonates showed fetal distress, none of the infant remained any sequelae at the time of the discharge. The other four were well although one of them complicated with meconium staining. As dynamic contrast MRI can differentiate chorionic villi and decidua basalis, and can provide excellent contrast between placenta and myometrium at anywhere within the uterus, it may be a promising technique for antepartum diagnosis of the placenta accreta.

Chorionic Villi↗

An object-oriented framework for dynamic ecosystem modeling: application for integrated risk assessment.

Ecological risk assessment requires the integration of a wide range of data on anthropogenic processes, ecological processes and on processes related to environmental fate and transport. It is a major challenge to assemble a simulation system that can successfully capture the dynamics of complex ecological systems and an even more serious challenge to be able to adapt such a simulation to shifting and expanding analytical requirements and contexts. The dynamic information architecture system (DIAS) is a flexible, extensible, object-based framework for developing and maintaining complex simulations. DIAS supports simulations in which the real-world entities that make up ecological systems are represented as software 'entity objects'. The object-oriented integrated dynamic landscape analysis and modeling system (OO-IDLAMS) provides a good example of how DIAS has been used to build a suite of models for the purpose of assessing the ecological impacts of military land use and land management practices. OO-IDLAMS is a prototype conservation modeling suite that provides military environmental managers and decision-makers with a strategic, integrated and adaptive approach to natural resources planning and ecosystem management. The OO-IDLAMS prototype used Fort Riley, Kansas as a case study to demonstrate DIAS' capabilities to offer flexibility, interprocess dynamics and cost-effective reuse of code for ecosystem modeling and simulation. DIAS can also readily lend itself to other applications in ecological risk assessment. It has great potential for the integration of ecological models (associated with biological uptake and effects) with environmental fate and transport models. A DIAS ecological risk assessment application could be used to predict the magnitude and extent of ecological risks and evaluate remedy effectiveness in a timely and cost-effective manner.

Animals↗

Dynamic neuro-immune regulation of psychiatric risk loci in human neurons.

The prenatal environment influences neurodevelopment and subsequent clinical trajectories for psychiatric outcomes in childhood and adolescence. Yet it remains unclear if the impact of maternal and fetal immune activation varies with distinct polygenic risk profiles. Therefore, here we catalogue genotype and environment (GxE) interactions, contrasting allele-specific regulatory activity between inflammatory contexts. We report a cue-specific neuronal massively parallel reporter assay (MPRA) of 220 loci from genome-wide association study (GWAS) linked to ten brain traits/disorders, empirically dissecting the impact of interleukin-6 (IL-6) and interferon-alpha (IFNα) on transcriptional activity. Of 1,469 active candidate regulatory risk elements (MPRA-active CRSs) across three conditions, we identify 316 with dynamic variant-specific effects (MPRA-QTLs) in human induced pluripotent stem cell (hiPSC)-derived glutamatergic neurons. Broadly, across hundreds of variants, neuronal immune-mediated regulatory activity is driven by differences in transcription factor binding and chromatin accessibility, the gene targets of which show pleiotropic enrichments for brain, metabolic, and immune disorders. Dynamic genetic regulation mediates immune effects, informing our understanding of mechanisms governing pleiotropy and variable penetrance. Understanding neurodevelopmental GxE interactions will inform mental health trajectories and resolve mechanisms mediating prenatal risk.

dynamic expression quantitative trait loci↗

The Estimate of Risk of Adolescent Sexual Offense Recidivism (ERASOR): preliminary psychometric data.

The Estimate of Risk of Adolescent Sexual Offense Recidivism (ERASOR) is an empirically guided checklist designed to assist clinicians to estimate the short-term risk of a sexual reoffense for youth aged 12-18 years of age. The ERASOR provides objective coding instructions for 25 risk factors (16 dynamic and 9 static). To investigate the psychometric properties, risk ratings were collected from 28 clinicians who evaluated 136 adolescent males (aged 12-18 years) following comprehensive, clinical assessments. Preliminary psychometric data (i.e., interrater agreement, item-total correlation, internal consistency) were found to be supportive of the reliability and item composition of the tool. ERASOR ratings also significantly discriminated adolescents based on whether or not they had previously been sanctioned for a prior sexual offense.

Adolescent↗

HUMTRN and EFFECTS: age and sex specific dosimetric and physiological human population dynamics models for dose assessment.

A human simulation model called HUMTRN and a population risk assessment model called EFFECTS were developed at Los Alamos National Laboratory as a major component of the BIOTRAN environmental risk assessment model. HUMTRN simulates growth using dietary and physiological characteristics and kinetics of radionuclides to predict radiation doses to selected organs of both sexes in different age groups. The model called EFFECTS was interfaced with output from HUMTRN to predict cancer risks in a dynamic human population. EFFECTS is based on the National Research Council Committee on the Biological Effects of Ionizing Radiation (BEIR)-III radiation cancer mortality estimates from the U.S. population mortality and natality estimates for both sexes between the ages of 1 and 70. These models track radiation intake from air, water, and food, calculate uptake in major growing organs, and estimate cancer mortality risks. This report documents the use of an IBM Personal Computer AT to run HUMTRN and EFFECTS. Air, water, and food contaminant concentrations are provided as input to HUMTRN, which then provides input for EFFECTS. The limitations of this approach are also discussed.

Age Factors↗

Risk factors and their effects on the dynamic process of smoking relapse among veteran smokers.

Smoking cessation programs can help smokers make a successful attempt at quitting, but many initial quitters relapse over time. This study aims to identify risk factors for smoking relapse and examine the influence of these factors on the dynamic relapse process in an outpatient smoking cessation program for veterans. Baseline information included socio-demographic description, medical and psychiatric comorbidities, smoking history and behavior, nicotine dependence, smoking motives, and confidence in the ability to quit. The intervention involved a 4-session group therapy consisting of cognitive and pharmacological treatments. The 189 initial quitters by program completion were followed via a telephone interview 6 months later. We identified six risk factors associated with relapse within the first 6 months post quit. Furthermore, we described characteristics of the dynamic process of smoking relapse and studied the influence of the identified risk factors on the relapse curve. The effects of these risk factors can be categorized into two patterns. Annual income and age at smoking initiation showed a delayed action that influenced the relapse curve after several weeks post quit, whereas age, number of smoking coworkers, history of schizophrenia, and number of sessions attended modified the relapse process soon after quitting. The information will be useful in targeting veteran smokers who are at high risk for relapse, choosing the optimal time for post-cessation services, and developing strategies accordingly.

Adult↗

A probabilistic transmission dynamic model to assess indoor airborne infection risks.

The purpose of this article is to quantify the public health risk associated with inhalation of indoor airborne infection based on a probabilistic transmission dynamic modeling approach. We used the Wells-Riley mathematical model to estimate (1) the CO2 exposure concentrations in indoor environments where cases of inhalation airborne infection occurred based on reported epidemiological data and epidemic curves for influenza and severe acute respiratory syndrome (SARS), (2) the basic reproductive number, R0 (i.e., expected number of secondary cases on the introduction of a single infected individual in a completely susceptible population) and its variability in a shared indoor airspace, and (3) the risk for infection in various scenarios of exposure in a susceptible population for a range of R0. We also employ a standard susceptible-infectious-recovered (SIR) structure to relate Wells-Riley model derived R0 to a transmission parameter to implicate the relationships between indoor carbon dioxide concentration and contact rate. We estimate that a single case of SARS will infect 2.6 secondary cases on average in a population from nosocomial transmission, whereas less than 1 secondary infection was generated per case among school children. We also obtained an estimate of the basic reproductive number for influenza in a commercial airliner: the median value is 10.4. We suggest that improving the building air cleaning rate to lower the critical rebreathed fraction of indoor air can decrease transmission rate. Here, we show that virulence of the organism factors, infectious quantum generation rates (quanta/s by an infected person), and host factors determine the risk for inhalation of indoor airborne infection.

Air Microbiology↗

Dynamic vessel wall properties and their reproducibility in subjects with increased cardiovascular risk.

OBJECTIVE: To determine reproducibility figures of dynamic arterial wall properties such as cross-sectional compliance (CC) and distensibility (DC) in subjects with increased cardiovascular risk, in comparison with healthy adults. METHODS: A total of 34 persons were divided into three groups with varying cardiovascular risk factors. Diameters (D) and diameter changes (deltaD) during the heart cycle of both common carotid (CCA) and right common femoral (CFA) arteries were measured by a vessel wall movement detector system. Blood pressures (BP) were recorded non-invasively by a semi-automated oscillometric device. CC (=piD(deltaD/2deltaP) in unit mm2/kPa) and DC (=2deltaD/D)/deltaP in unit 10(-3)/kPa) were calculated from the above-mentioned parameters. Measurements were performed twice during one visit and twice again with a time interval of at least 3 days to determine intra-observer intra- and intersession variability. RESULTS: Reproducibility figures of CC and DC of the CCA varied between 8 and 12%, and between 13 and 22% for the CFA. Intra-observer intra- and intersession variability were similar in the three groups. CONCLUSIONS: In our studies the reproducibility of dynamic vascular wall properties determined by ultrasound was good. Despite differences in the absolute values for CC and DC in groups with increased cardiovascular risk, mean reproducibility figures remained at a similar level (8-12%) as in healthy volunteers.

Adult↗

Marked improvements in outcomes of contemporary percutaneous coronary intervention in patients with diabetes mellitus.

We sought to determine if advances in percutaneous coronary intervention (PCI) are associated with better outcomes among patients with diabetes mellitus (DM). Patients with DM enrolled in the National Heart, Lung, and Blood Institute (NHLBI) early PTCA Registry (1985-1986) were compared to those in the subsequent contemporary Dynamic Registry (1999-2002) for in-hospital and one-year cardiovascular outcomes. The study population included 945 adults with DM, 325 from the PTCA Registry and 620 from the Dynamic Registry. Multivariable Cox regression models were built to estimate the risk of clinical events. Dynamic Registry patients were older, had more noncardiac comorbidities, and a lower mean ejection fraction (50.5% vs 57.8%, P < or = 0.001) compared to the PTCA Registry patients. The incidence of in-hospital mortality (1.9% vs 4.3%, P < or = 0.05), myocardial infarction (MI) (1.0% vs 7.4%, P <or = 0.001), and coronary artery bypass grafting (CABG) (0.8% vs 6.2%, P < or = 0.001) were all significantly lower and independent of the use of stents. One-year adverse events including MI (4.9% vs 11.0%, P < or = 0.001), CABG (6.4% vs 15.0%, P < or = 0.001), and need for repeat revascularization (18.7% vs 33.3%, P < or = 0.001) were all lower in the Dynamic Registry. The relative risk of death at 1 year was significantly less for patients in the Dynamic Registry (RR 0.56, 0.34; 0.92, P = 0.02). Although Dynamic Registry patients with diabetes had more advanced coronary disease, in-hospital and late adverse events were lower. A combination of the use of stents and an increase in adjunctive medical therapy are likely responsible for the observed improvements in outcomes in contemporary PCI.

Angioplasty, Balloon, Coronary↗

Predicting fall risks in an elderly population: computer dynamic posturography versus electronystagmography test results.

OBJECTIVES/HYPOTHESIS: Falls are the leading cause of morbidity and mortality for persons aged 65 years and older, with more than 2 million people falling and sustaining serious injury annually. This study compared computer dynamic posturography (CDP) and electronystagmography (ENG) results as predictors of falls. STUDY DESIGN: Retrospective. METHODS: Thirty-three patients over the age of 65 years who presented to a balance disorders and falls prevention clinic were used for this study (22 women and 11 men, with an average age of 78.0 y and a mean fall rate of 3.5 times). All had experienced at least one fall in the year before visiting the clinic and were tested with both CDP and ENG. The CDP results were divided into subcategories (sensory organization testing and limits of stability); ENG results were divided into four categories (ocular motor, rotational chair, positional, and caloric studies). RESULTS: Test findings were classified as normal or abnormal based on age-matched normative data. Of the patients in the study, 27.3% were normal for one type of testing and abnormal for the other. Twenty-six patients (78.8%) had abnormal results on CDP, and 20 individuals (60.6%) showed ENG abnormalities (42.4% for ocular motor, 28.6% for positional, 13.6% for caloric, and 11.2% for rotational chair studies). The limits of stability category was significant in predicting multiple falls. CONCLUSION: For this population, CDP was determined to be a more sensitive test for identifying patients who have fallen, with limits of stability testing the most significant part of the CDP battery; for ENG studies, the best falls indicator was the ocular motor battery.

Accidental Falls↗

HIV infection dynamics and intervention experiments in linked risk groups.

A multigroup transmission model is described to study the spread of the human immunodeficiency virus (HIV) in linked risk groups. The model permits simultaneous investigation of the increase in the number of persons infected with HIV in three main risk groups: promiscuous homo/bisexual men (two levels of promiscuity), intravenous drug users (men and women) and promiscuous heterosexual men and women. Three modes of transmission are considered: anal and vaginal intercourse and needle sharing. The high dimensional parameter space is connected with the HIV incidence through a transmission matrix. This matrix summarizes the annual effective contact rates due to the three transmission modes. The model helps to clarify which data are needed to disentangle the relative contribution of the within- and between-group transmission routes. The model can be used to perform theoretical experiments. Given a specification of a baseline, the potential use of the model is illustrated by a simulation describing the effect of blocking the transmission through needle sharing. Reference is made to the HIV/AIDS epidemic in The Netherlands. The results of the study show that the model can play a part in the classification of HIV prevalence patterns in linked risk groups, in the study of the interaction between the main risk groups and in the theoretical evaluation of intervention measures.

Female↗

Azaspiracid shellfish poisoning: unusual toxin dynamics in shellfish and the increased risk of acute human intoxications.

A number of recent acute human intoxications in Europe from the consumption of Irish mussels have been attributed to the presence of a new class of toxins named azaspiracids. The study demonstrates that azaspiracids behave differently from other polyether toxins, and this accounts for most false-negative results in the mouse bioassay employed by regulatory agencies to detect azaspiracids. Typically, polyether toxins are concentrated in the digestive glands of shellfish, but this is not always the situation with azaspiracids. Liquid chromatography-mass spectrometry (LC-MS), especially multiple tandem MS methods, have been applied to demonstrate that azaspiracid (AZA1) and its methyl- and demethyl- analogues, AZA2 and AZA3 respectively, are distributed throughout shellfish tissues. Using conventional mouse bioassay protocols, only 0-40% of the total azaspiracid content of shellfish was used in the assay, which could directly account for false-negative results. It was also observed that the toxin profiles differed significantly in various mussel tissues with AZA1 as the predominant toxin in the digestive glands and AZA3 predominant in the remaining tissues.

Acute Disease↗

Medical application of engineering risk analysis and anesthesia patient risk illustration.

The engineering risk analysis method can be extended to include some human and organizational factors and can be used in the medical domain; this transfer is illustrated by a description of a study of anesthesia patient risk. This study involves first a dynamic analysis of accident risks. The model is then extended by relating the basic events of accident scenarios to the state of the practitioner described by the probability of personal problems that may affect his or her level of competence and alertness. These potential problems, in turn, are linked (by probabilistic relations) to the way the system is managed. This extension of the analytical framework allows assessment of the effect of particular types of practitioner problems and therefore of corresponding risk mitigation measures on the probability of the different accident scenarios. The risk analysis model can then be used as a management tool that permits setting priorities among patient safety measures, based either on the sole benefits of the corresponding decrease of patient risk or on a cost-to-benefit ratio. This probabilistic approach constitutes a departure from the classic risk studies exclusively based on statistical frequencies because it involves both available statistics and expert opinions. It is commonly used in engineering for systems for which there is not enough information at the time when decisions need to be made. I show here how the probabilistic model can be used in the medical field to support patient safety decisions before complete data sets can be gathered or in cases in which some key factors are not directly observable.

Anesthesia↗

A dynamic model to assess microbial health risks associated with beneficial uses of biosolids.

There is increasing interest in the development of a microbial risk assessment methodology for regulatory and operational decision making. This document presents a methodology for assessing risks to human health from pathogen exposure using a population-based model that explicitly accounts for properties unique to an infectious disease process, specifically secondary transmission and immunity. To demonstrate the applicability of this risk-based method, numerical simulations were carried out for a case study example in which the route of exposure was direct consumption of biosolids-amended soil and the pathogen present in the soil was enterovirus. The output from the case study yielded a decision tree that differentiates between conditions in which the relative risk from biosolids exposure is high and those conditions in which the relative risk from biosolids is low. This decision tree illustrates the interaction among the important factors in quantifying risk. For the case study example, these factors include biosolids treatment processes, the pathogen shedding rate of infectious individuals, secondary transmission, and immunity. Further refinement in methods for determining biosolids exposures under field conditions would certainly increase the utility of these approaches.

Decision Trees↗

The association between the purchase of a handgun and homicide or suicide.

OBJECTIVES: The purpose of this study was to determine whether purchase of a handgun from a licensed dealer is associated with the risk of homicide or suicide and whether any association varies in relation to time since purchase. METHODS: A case-control study was done among the members of a large health maintenance organization. Case subjects were the 353 suicide victims and 117 homicide victims among the members from 1980 through 1992. Five control subjects were matched to each case subject on age, sex, and zip code of residence. Handgun purchase information was obtained from the Department of Licensing. RESULTS: The adjusted relative risk of suicide was 1.9 (95% confidence interval [CI] = 1.4, 2.5) for persons with a history of family handgun purchase from a registered dealer. The adjusted relative risk for homicide, given a history of family handgun purchase, was 2.2 (95% CI = 1.3, 3.7). For both suicide and homicide, the elevated relative risks persisted for more than 5 years after the purchase. CONCLUSIONS: Legal purchase of a handgun appears to be associated with a long-lasting increased risk of violent death.

Adolescent↗