299 research outputs found

    CMOs, Duration Risk and a New Mortgage

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    This article presents an alternative mortgage that retains the fixed-rate feature of a fixed-rate mortgage (FRM), but accelerates the principal amortization when interest rates rise, exposing the buyer to less duration risk in a rising interest rate environment. This mortgage, labeled the adjustable amortization mortgage (AAM), is shown to have lessened interest rate risk for the buyer as well as lower default risk, suggesting that it should be priced higher (at a lower rate of interest) than the typical FRM. It is also shown that mortgage-backed securities collateralized by an AAM have much less price volatility than mortgage-backed securities backed by FRMs.

    The Zero-Coupon/Interest-Only Fixed-Rate Mortgage: An Alternative for Funding Low-to-Moderate Income Housing

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    This proposal sets forth a concept for the public/private finance of owner-occupied, single-family homes for first-time homebuyers utilizing federal guarantees and private sector mortgages. Proposed funding requires no new tax revenues. The security that the program revolves around is a Zero-coupon/Interest-only Fixed-rate mortgage (ZIF). The ZIF has the potential to improve the allocation of resources for subsidizing low-income housing, to reduce risk exposure to rapidly declining property values, and to improve the self-esteem of a group of Americans who have been depressed for far too long by making homeownership a reality.

    Application of asymptotic expansions of maximum likelihood estimators errors to gravitational waves from binary mergers: the single interferometer case

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    In this paper we describe a new methodology to calculate analytically the error for a maximum likelihood estimate (MLE) for physical parameters from Gravitational wave signals. All the existing litterature focuses on the usage of the Cramer Rao Lower bounds (CRLB) as a mean to approximate the errors for large signal to noise ratios. We show here how the variance and the bias of a MLE estimate can be expressed instead in inverse powers of the signal to noise ratios where the first order in the variance expansion is the CRLB. As an application we compute the second order of the variance and bias for MLE of physical parameters from the inspiral phase of binary mergers and for noises of gravitational wave interferometers . We also compare the improved error estimate with existing numerical estimates. The value of the second order of the variance expansions allows to get error predictions closer to what is observed in numerical simulations. It also predicts correctly the necessary SNR to approximate the error with the CRLB and provides new insight on the relationship between waveform properties SNR and estimation errors. For example the timing match filtering becomes optimal only if the SNR is larger than the kurtosis of the gravitational wave spectrum

    Phylogeny of Lantana, Lippia, and related genera (Lantaneae: Verbenaceae)

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    Premise: Lantana and Lippia (Verbenaceae) are two large Linnean genera whose classification has been based on associated fruit traits: fleshy vs. dry fruits and one vs. two seed-bearing units. We reconstruct evolutionary relationships and the evolution of the two fruit traits to test the validity of these traits for classification. Methods: Previous studies of plastid DNA sequences provided limited resolution for this group. Consequently, seven nuclear loci, including ITS, ETS, and five PPR loci, were sequenced for 88 accessions of the Lantana/Lippia clade and three outgroups. Results: Neither Lantana nor Lippia is monophyletic. Burroughsia, Nashia, Phyla, and several Aloysia species are included within the clade comprising Lantana and Lippia. We provide a hypothesis for fruit evolution and biogeographic history in the group and their relevance for classification. Conclusions: Fleshy fruits evolved multiple times in the Lantana/Lippia clade and thus are not suitable taxonomic characters. Several sections of Lantana and Lippia and the small genera are monophyletic, but Lippia section Zappania is broadly paraphyletic, making circumscription of genera difficult. Lippia sect. Rhodolippia is a polyphyletic group characterized by convergence in showy bracts. Species of Lantana sect. Sarcolippia, previously transferred to Lippia, are not monophyletic. The clade originated and diversified in South America, with at least four expansions into both Central America and the Caribbean and two to Africa. The types species of Lantana and Lippia occur in small sister clades, rendering any taxonomy that retains either genus similar to its current circumscription impossible.Fil: Lu Irving, Patricia. University of Washington; Estados UnidosFil: Bedoya, Ana M.. University of Washington; Estados UnidosFil: Salimena, Fátima R. G.. Universidade Federal de Juiz de Fora; BrasilFil: dos Santos Silva, Tânia R.. Universidade Estadual de Feira de Santana; BrasilFil: Viccini, Lyderson F.. Universidade Federal de Juiz de Fora; BrasilFil: Bitencourt, Cássia. Universidade Estadual de Feira de Santana; BrasilFil: Thode, Verônica. Universidade Federal do Rio Grande do Sul; BrasilFil: Cardoso, Pedro H.. Universidade Federal Do Rio de Janeiro. Museu Nacional; BrasilFil: O'Leary, Nataly Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Olmstead, Richard. University of Washington; Estados Unido

    Estado actual de la investigación arqueometalúrgica prehistórica en la provincia de Málaga

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    The lack of data on prehistoric metallurgical activities in Málaga made local prehistorians think that all the metal artefacts recovered in the province were of non-local origin. As a result of a project funded by the Junta de Andalucía, new data have been collected and we can begin to outline the development and socioeconomic importance that metal technologies have in different parts of Málaga throughout prehistory.La práctica inexistencia de datos sobre actividades metalúrgicas prehistóricas en Málaga y el vacío investigador que sobre este aspecto existía en la provincia habían creado un estado de opinión entre los prehistoriadores locales tendente a considerar como de origen extraprovincial la totalidad de los artefactos metálicos prehistóricos recuperados. Como resultado de un proyecto subvencionado por la Junta de Andalucía, estos datos que faltaban comienzan ahora a ser recuperados, y se puede empezar a trazar un esbozo general del desarrollo e importancia socieconómica que este grupo de tecnologías tuvieron en los diversos ambientes geográficos de la provincia de Málaga durante la prehistoria

    Delegation of GP-home visits to qualified practice assistants: assessment of economic effects in an ambulatory healthcare centre

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    <p>Abstract</p> <p>Background</p> <p>Against the background of a decreasing number of general practitioners (GPs) in rural regions in Germany, the AGnES-concept (AGnES = GP-supporting, community-based, e-health-assisted, systemic intervention) supports the delegation of regular GP-home visits to qualified practice assistants. The concept was implemented and evaluated in different model projects in Germany.</p> <p>To explore the economic effects of this concept, the development of the number of home visits in an ambulatory healthcare centre was analysed and compared with the number of home visits in the surrounding county.</p> <p>Methods</p> <p>Information about GP-home visits was derived from reimbursement data of the ambulatory healthcare centre and a statutory health insurance. Information about home visits conducted by AGnES-practice assistants was collected from the project documentation over a time period of 12 consecutive quarter years, four quarter years before the beginning of the project and 8 quarter years while the project was implemented, considering background temporal trends on the population level in the study region.</p> <p>Results</p> <p>Within the ambulatory healthcare centre, the home visits by the GPs significantly decreased, especially the number of medically urgent home visits. However, the overall rate of home visits (conducted by the GPs and the AGnES-practice assistants together) did not change significantly after implementation of the AGnES-concept. In the surrounding county, the home visit rates of the GPs were continuous; the temporal patterns were approximately equal for both usual and urgent home visits.</p> <p>Conclusion</p> <p>The results of the analyses show that the support by AGnES-practice assistants led to a decrease of GP-home visits rather than an induction of additional home visits by the AGnES-practice assistants. The most extended effect is related to the medically urgent home visits rather than to the usual home visits.</p

    Role of adenylate cyclase 9 in the pharmacogenomic response to dalcetrapib clinical paradigm and molecular mechanisms in precision cardiovascular medicine

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    Following the neutral results of the dal-OUTCOMES trial, a genome-wide study identified the rs1967309 variant in the adenylate cyclase type 9 (ADCY9) gene on chromosome 16 as being associated with the risk of future cardiovascular events only in subjects taking dalcetrapib, a CETP (cholesterol ester transfer protein) modulator. Homozygotes for the minor A allele (AA) were protected from recurrent cardiovascular events when treated with dalcetrapib, while homozygotes for the major G allele (GG) had increased risk. Here, we present the current state of knowledge regarding the impact of rs1967309 in ADCY9 on clinical observations and biomarkers in dalcetrapib trials and the effects of mouse ADCY9 gene inactivation on cardiovascular physiology. Finally, we present our current model of the interaction between dalcetrapib and ADCY9 gene variants in the arterial wall macrophage, based on the intracellular role of CETP in the transfer of complex lipids from endoplasmic reticulum membranes to lipid droplets. Briefly, the concept is that dalcetrapib would inhibit CETP-mediated transfer of cholesteryl esters, resulting in a progressive inhibition of cholesteryl ester synthesis and free cholesterol accumulation in the endoplasmic reticulum. Reduced ADCY9 activity, by paradoxically leading to higher cyclic AMP levels and in turn increased cellular cholesterol efflux, could impart cardiovascular protection in rs1967309 AA patients. The ongoing dal-GenE trial recruited 6145 patients with the protective AA genotype and will provide a definitive answer to whether dalcetrapib will be protective in this population.Cardiolog

    Diversity in sound pressure levels and estimated active space of resident killer whale vocalizations

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    Author Posting. © The Author, 2005. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Journal of Comparative Physiology A: Sensory, Neural, and Behavioral Physiology 192 (2006): 449-459, doi:10.1007/s00359-005-0085-2.Signal source intensity and detection range, which integrates source intensity with propagation loss, background noise and receiver hearing abilities, are important characteristics of communication signals. Apparent source levels were calculated for 819 pulsed calls and 24 whistles produced by free-ranging resident killer whales by triangulating the angles-of-arrival of sounds on two beamforming arrays towed in series. Levels in the 1-20 kHz band ranged from 131-168 dB re 1μPa @1m, with differences in the means of different sound classes (whistles: 140.2 ± 4.1 dB; variable calls: 146.6 ± 6.6 dB; stereotyped calls: 152.6 ± 5.9 dB), and among stereotyped call types. Repertoire diversity carried through to estimates of active space, with “long-range” stereotyped calls all containing overlapping, independently-modulated high-frequency components (mean estimated active space of 10-16km in sea state zero) and “short-range” sounds (5-9 km) included all stereotyped calls without a high-frequency component, whistles, and variable calls. Short-range sounds are reported to be more common during social and resting behaviors, while long-range stereotyped calls predominate in dispersed travel and foraging behaviors. These results suggest that variability in sound pressure levels may reflect diverse social and ecological functions of the acoustic repertoire of killer whales.Funding was provided by WHOI’s Ocean Ventures Fund and Rinehart Coastal Research Center and a Royal Society fellowship

    Characterization of Synaptically Connected Nuclei in a Potential Sensorimotor Feedback Pathway in the Zebra Finch Song System

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    Birdsong is a learned behavior that is controlled by a group of identified nuclei, known collectively as the song system. The cortical nucleus HVC (used as a proper name) is a focal point of many investigations as it is necessary for song production, song learning, and receives selective auditory information. HVC receives input from several sources including the cortical area MMAN (medial magnocellular nucleus of the nidopallium). The MMAN to HVC connection is particularly interesting as it provides potential sensorimotor feedback to HVC. To begin to understand the role of this connection, we investigated the physiological relation between MMAN and HVC activity with simultaneous multiunit extracellular recordings from these two nuclei in urethane anesthetized zebra finches. As previously reported, we found similar timing in spontaneous bursts of activity in MMAN and HVC. Like HVC, MMAN responds to auditory playback of the bird's own song (BOS), but had little response to reversed BOS or conspecific song. Stimulation of MMAN resulted in evoked activity in HVC, indicating functional excitation from MMAN to HVC. However, inactivation of MMAN resulted in no consistent change in auditory responses in HVC. Taken together, these results indicate that MMAN provides functional excitatory input to HVC but does not provide significant auditory input to HVC in anesthetized animals. We hypothesize that MMAN may play a role in motor reinforcement or coordination, or may provide modulatory input to the song system about the internal state of the animal as it receives input from the hypothalamus
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