Optimal vaccination in a stochastic epidemic model of two non-interacting populations

Developing robust, quantitative methods to optimize resource allocations in response to epidemics has the potential to save lives and minimize health care costs. In this paper, we develop and apply a computationally efficient algorithm that enables us to calculate the complete probability distribution for the final epidemic size in a stochastic Susceptible-Infected-Recovered (SIR) model. Based on these results, we determine the optimal allocations of a limited quantity of vaccine between two non-interacting populations. We compare the stochastic solution to results obtained for the traditional, deterministic SIR model. For intermediate quantities of vaccine, the deterministic model is a poor estimate of the optimal strategy for the more realistic, stochastic case.Comment: 21 pages, 7 figure

Small Employer Perspectives On The Affordable Care Act's Premiums, SHOP Exchanges, And Self-Insurance

Beginning January 1, 2014, small businesses having no more than fifty full-time-equivalent workers will be able to obtain healthinsurance for their employees through Small Business Health OptionsProgram (SHOP) exchanges in every state. Although the Affordable Care Act intended the exchanges to make the purchasing of insurance moreattractive and affordable to small businesses, it is not yet known how they will respond to the exchanges. Based on a telephone survey of 604 randomly selected private firms having 3 -- 50 employees, we found that both firms that offered health coverage and those that did not rated most features of SHOP exchanges highly but were also very price sensitive.More than 92 percent of nonoffering small firms said that if they were to offer coverage, it would be "very" or "somewhat" important to them that premium costs be less than they are today. Eighty percent of offering firms use brokers who commonly perform functions of benefit managers -- functions that the SHOP exchanges may assume. Twenty-six percent of firms using brokers reported discussing self-insuring with their brokers. An increase in the number of self-insured small employers could pose a threat to SHOP exchanges and other small-group insurance reforms

An Analysis of the Changes in the Prevalence of Camallanus Oxycephalus (Nematoda: Camallanidae) in Western Lake Erie

Author Institution: Center for Lake Erie Area Research and The Department of Zoology, Ohio State UniversitySTROMBERG, PAUL C. AND CRITES, JOHN L. An Analysis of the Changes in the Prevalence of Camallanus oxycephalus (Nematoda: Camallanidae) in Western Lake Erie. Ohio J. Sci. 75(1): 1, 1975. Distribution of Camallanus oxycephalus was studied in 16 species of fishes in western Lake Erie during the summer and autumn of 1972. This study was compared to studies done in 1927 and 1957. Analysis of the frequency of infection in these fishes indicates that Camallanus has become more abundant in the lake. This increase has occurred since 1957. The increase in prevalence appears related to changes in plankton, benthos and fish communities of the western basin. The importance of hostparasite contact frequency and its relation to parasite population density and regulation is discussed

Court Interpreter Training in the Language Laboratory

Demographic studies and statistics from state and federal courts indicate agrowing need for Spanish-English court interpreters with special training in consecutiveand simultaneous court interpretation. The authors conducted a survey of 466 ofCalifornia's Spanish-English court interpreters to determine what the Spanish-Englishcourt interpreter's strongest skills needs are. Survey results are reported in this article,and the five strongest skills training needs are identified. The authors indicate how thelanguage laboratory may efficiently be used to develop and enhance these five skillsand how it may best serve a court interpreter training program. Emphasis is onapplying the work of G.A. Miller and the training techniques of Robert Ingram toSpanish-English court interpreter training

The Origin of the External Basins of the Betics, Southern Spain, and Their Use in Interpreting the Orogenic History

The Betic mountain chain of Southern Spain, together with the Rif Mountains of N.W. Africa forms the western-most extension of the Alpine mountain chain in Europe. The Orogen formed as a direct result of the interaction between the African and Iberian plates which took place from the late Cretaceous onwards. The origin of the Betics is far from understood and there are several conflicting hypotheses concerning the origin of the Orogen. There are two major external basins to the Betic Orogen in Southern Spain, the Guadalquivir Basin and the Gibraltar Arc Flysch, and both provide important insights into its tectonic history. The Guadalquivir Basin lies on the northern margin of the External Zone Tertiary fold-thrust belt of the Betic Orogen and south of the Palaeozoic Iberian Meseta. It can be subdivided into structurally distinct regions, an undeformed autochthonous basin which lies to the north of a deformed allochthonous basin. The origin of the Guadalquivir Basin (previously interpreted as being the foreland basin to the Orogen) is questioned. Structured sedimentological and provenance studies demonstrate that the Guadalquivir Basin is not a foreland basin because; 1. It formed as an integral part of the destruction of the Iberian passive margin during which time thin skinned thrusting generated a basin on the northern margin of the External Zones, 2. The fill and unconformities of this basin were controlled by eustasy rather by the tectonic incursion of an orogenic wedge being driven onto the Iberian Margin, 3. The basin did not form by the downward flexure of the lithosphere in response to an orogenic load. Therefore the basin cannot be considered to be a true foreland basin. The clastic sedimentation in the Guadalquivir Basin was controlled by the emergence of the External Zone thrust sheet, during the late Miocene, which was related to the thin skinned thrusting. During this time the recycling of material, that had originally been derived from the Palaeozoic Iberian Meseta. took place. A thrusting event at the the end of the Miocene/ early Pliocene led to the destruction of the Guadalquivir Basin which was subdivided into the allochthon and autochthon seen today. The Gibraltar Arc flysch nappes link the External Rif of North Africa to the External Zone of Southern Spain. The largest unit of the Gibraltar Arc is the Aljibe Flysch which can be subdivided into the Beneiza Flysch and Aljibe Arenites, which are Oligo-Miocene in age. The Beneiza Flysch is characterised by thin sandstones and siltstones that are interpreted to have been deposited by turbiditic currents. These pass rapidly upwards into the thick bedded and super-mature Aljibe Arenites, which are entirely dominated by water escape- structures. The contact between these two units marks a dramatic change in the depositional environment at the beginning of the Miocene. The Aljibe Flysch is interpreted as recording the development of a basin plain that became tectonically segregated at the beginning of the Miocene, at which time new and tectonically confined basins developed. Tectonic instabilities created elsewhere in the External Zone resulted in mobilisation of large amounts of sediment which was rapidly deposited in the newly created basins. The flysch units have subsequently been thrust westwards post-Lower Miocene during which time peridotites were emplaced into mid-crustal levels Consideration of the tectonic and sedimentary history of the Guadalquivir Basin and Gibraltar Arc Flysch provides an important insight into the tectonic history of the Betic Orogen. Data collected during the study of these basins, combined with important new published data from the Alboran Sea and Ronda Peridotites, has resulted in the rejection of the widely accepted 'extensional collapse' model and in the identification of strike-slip tectonism and transcurrent movements as the main mechanism for the building of the Betic Orogen. Miocene transcurrent movements in the Betic area resulted in the break up the Iberian passive margin, the emplacement of metamorphic terranes and in the formation of thrusts in the Gibraltar Arc through a complicated history of transtension and transpression in the region of the Alboran sea

Development and initial testing of the self‐care of chronic illness inventory

Aim The aim was to develop and psychometrically test the self‐care of chronic illness Inventory, a generic measure of self‐care. Background Existing measures of self‐care are disease‐specific or behaviour‐specific; no generic measure of self‐care exists. Design Cross‐sectional survey. Methods We developed a 20‐item self‐report instrument based on the Middle Range Theory of Self‐Care of Chronic Illness, with three separate scales measuring Self‐Care Maintenance, Self‐Care Monitoring, and Self‐Care Management. Each of the three scales is scored separately and standardized 0–100 with higher scores indicating better self‐care. After demonstrating content validity, psychometric testing was conducted in a convenience sample of 407 adults (enrolled from inpatient and outpatient settings at five sites in the United States and ResearchMatch.org). Dimensionality testing with confirmatory factor analysis preceded reliability testing. Results The Self‐Care Maintenance scale (eight items, two dimensions: illness‐related and health‐promoting behaviour) fit well when tested with a two‐factor confirmatory model. The Self‐Care Monitoring scale (five items, single factor) fitted well. The Self‐Care Management scale (seven items, two factors: autonomous and consulting behaviour), when tested with a two‐factor confirmatory model, fitted adequately. A simultaneous confirmatory factor analysis on the combined set of items supported the more general model. Conclusion The self‐care of chronic illness inventory is adequate in reliability and validity. We suggest further testing in diverse populations of patients with chronic illnesses

Professional Reading

The Teaching of Ethics in the Militar