A hybrid zone with coincident clines for autosomal and sex-specific markers in the Sorex araneus group.

In hybrid zones, endogenous counter-selection of hybrids is usually first expressed as reduced fertility or viability in hybrids of the heterogametic sex, a mechanism known as Haldane's rule. This phenomenon often leads to a differential of gene flow between sex-linked markers. Here, we address the possibility of a differential gene flow for Y chromosome, mtDNA and autosomal markers across the hybrid zone between the genetically and chromosomally well-differentiated species Sorex antinorii and Sorex araneus race Vaud. Intermarker comparison clearly revealed coincidental centre and very abrupt clines for all three types of markers. The overall level of genetic differentiation between the two species must be strong enough to hinder asymmetric introgression. Cyto-nuclear mismatches were also observed in the centre of hybrid zone. The significantly lower number of mismatches observed in males than in females possibly results from Y chromosome-mtDNA interactions. Results are compared with those previously reported in another hybrid zone between S. antinori and S. araneus race Cordon.

Gene-flow in a mosaic hybrid zone: is local introgression adaptive?

Genome-wide scans of genetic differentiation between hybridizing taxa can identify genome regions with unusual rates of introgression. Regions of high differentiation might represent barriers to gene flow, while regions of low differentiation might indicate adaptive introgression-the spread of selectively beneficial alleles between reproductively isolated genetic backgrounds. Here we conduct a scan for unusual patterns of differentiation in a mosaic hybrid zone between two mussel species, Mytilus edulis and M. galloprovincialis. One outlying locus, mac-1, showed a characteristic footprint of local introgression, with abnormally high frequency of edulis-derived alleles in a patch of M. galloprovincialis enclosed within the mosaic zone, but low frequencies outside of the zone. Further analysis of DNA sequences showed that almost all of the edulis allelic diversity had introgressed into the M. galloprovincialis background in this patch. We then used a variety of approaches to test the hypothesis that there had been adaptive introgression at mac-1. Simulations and model fitting with maximum-likelihood and approximate Bayesian computation approaches suggested that adaptive introgression could generate a "soft sweep," which was qualitatively consistent with our data. Although the migration rate required was high, it was compatible with the functioning of an effective barrier to gene flow as revealed by demographic inferences. As such, adaptive introgression could explain both the reduced intraspecific differentiation around mac-1 and the high diversity of introgressed alleles, although a localized change in barrier strength may also be invoked. Together, our results emphasize the need to account for the complex history of secondary contacts in interpreting outlier loci.

Soil Survey of Clay County, Iowa, 2005

The general soil map, which is a color map, shows the survey area divided into groups of associated soils called general soil map units. This map is useful in planning the use and management of large areas. To find information about your area of interest, locate that area on the map, identify the name of the map unit in the area on the color-coded map legend, then refer to the section General Soil Map Units for a general description of the soils in your area.

Les cures hybrides des lésions anévrismales [Hybrid treatment of aortic aneurysms]

The hybrid treatment of aortic aneurysms is indicated in patients having the ostia of supra aortic or visceral branches taken in to the aneurysm. Indeed, these lesions are not eligible for classic endovascular treatment because the existing endoprostheses cannot provide perfusion of the side branches without inducing major endoleaks. The surgical technique consists of 2 steps: firstly, a by-pass between normal aorta and the major aortic branches involved in the aneurysm is performed to guarantee the perfusion of the organs such as brain, bowel, and after endoprosthesis deployment. Secondly, the endoprosthesis is deployed using the classical technique to isolate the aneurysm. The hybrid approach provides safe and reliable treatment of complex aortic aneurysms with mortality and morbidity rate far below the classical open surgery.

Isotopic variation across the Audubon's-myrtle warbler hybrid zone.

Differences in seasonal migratory behaviours are thought to be an important component of reproductive isolation in many organisms. Stable isotopes have been used with success in estimating the location and qualities of disjunct breeding and wintering areas. However, few studies have used isotopic data to estimate the movements of hybrid offspring in species that form hybrid zones. Here, we use stable hydrogen to estimate the wintering locations and migratory patterns of two common and widespread migratory birds, Audubon's (Setophaga auduboni) and myrtle (S. coronata) warblers, as well as their hybrids. These two species form a narrow hybrid zone with extensive interbreeding in the Rocky Mountains of British Columbia and Alberta, Canada, which has been studied for over four decades. Isotopes in feathers grown on the wintering grounds or early on migration reveal three important patterns: (1) Audubon's and myrtle warblers from allopatric breeding populations winter in isotopically different environments, consistent with band recovery data and suggesting that there is a narrow migratory transition between the two species, (2) most hybrids appear to overwinter in the south-eastern USA, similar to where myrtle warblers are known to winter, and (3) some hybrid individuals, particularly those along the western edge of the hybrid zone, show Audubon's-like isotopic patterns. These data suggest there is a migratory divide between these two species, but that it is not directly coincident with the centre of the hybrid zone in the breeding range. We interpret these findings and discuss them within the context of previous research on hybrid zones, speciation and migratory divides.

A dynamic choice model of hybrid behavior in the attribute-space

This paper presents a dynamic choice model in the attributespace considering rational consumers that discount the future. In lightof the evidence of several state-dependence patterns, the model isfurther extended by considering a utility function that allows for thedifferent types of behavior described in the literature: pure inertia,pure variety seeking and hybrid. The model presents a stationaryconsumption pattern that can be inertial, where the consumer only buysone product, or a variety-seeking one, where the consumer buys severalproducts simultane-ously. Under the inverted-U marginal utilityassumption, the consumer behaves inertial among the existing brands forseveral periods, and eventually, once the stationary levels areapproached, the consumer turns to a variety-seeking behavior. An empiricalanalysis is run using a scanner database for fabric softener andsignificant evidence of hybrid behavior for most attributes is found,which supports the functional form considered in the theory.

Intraoperative angiography reloaded: a new hybrid operating theater for combined endovascular and surgical treatment of cerebral arteriovenous malformations: a pilot study on 25 patients.

BACKGROUND: Multimodality treatment suites for patients with cerebral arteriovenous malformations (AVM) have recently become available. This study was designed to evaluate feasibility, safety and impact on treatment of a new intraoperative flat-panel (FP) based integrated surgical and imaging suite for combined endovascular and surgical treatment of cerebral AVM. METHODS: Twenty-five patients with AVMs to treat with combined endovascular and surgical interventions were prospectively enrolled in this consecutive case series. The hybrid suite allows combined endovascular and surgical approaches with intraoperative scanner-like imaging (XperCT®) and intraoperative 3D rotational angiography (3D-RA). The impact of intraoperative multimodal imaging on feasibility, workflow of combined interventions, surgery, and unexpected imaging findings were analyzed. RESULTS: Twenty-five patients (mean age 38 ± 18.6 year) with a median Spetzler-Martin grade 2 AVM (range 1-4) underwent combined endovascular and surgical procedures. Sixteen patients presented with a ruptured AVM and nine with an unruptured AVM. In 16 % (n = 4) of cases, intraoperative imaging visualized AVM remnants ≤3 mm and allowed for completion of the resections in the same sessions. Complete resection was confirmed in all n = 16 patients who had follow-up angiography one year after surgery so far. All diagnostic and therapeutical steps, including angiographic control, were performed without having to move the patients CONCLUSION: The hybrid neurointerventional suite was shown to be a safe and useful setup which allowed for unconstrained combined microsurgical and neuroradiological workflow. It reduces the need for extraoperative angiographic controls and subsequent potential surgical revisions a second time, as small AVM remnants can be detected with high security.

Hybrid consumption paths in the attribute space: A model and application with scanner data

This paper presents and estimates a dynamic choice model in the attribute space considering rational consumers. In light of the evidence of several state-dependence patterns, the standard attribute-based model is extended by considering a general utility function where pure inertia and pure variety-seeking behaviors can be explained in the model as particular linear cases. The dynamics of the model are fully characterized by standard dynamic programming techniques. The model presents a stationary consumption pattern that can be inertial, where the consumer only buys one product, or a variety-seeking one, where the consumer shifts among varied products.We run some simulations to analyze the consumption paths out of the steady state. Underthe hybrid utility assumption, the consumer behaves inertially among the unfamiliar brandsfor several periods, eventually switching to a variety-seeking behavior when the stationary levels are approached. An empirical analysis is run using scanner databases for three different product categories: fabric softener, saltine cracker, and catsup. Non-linear specifications provide the best fit of the data, as hybrid functional forms are found in all the product categories for most attributes and segments. These results reveal the statistical superiority of the non-linear structure and confirm the gradual trend to seek variety as the level of familiarity with the purchased items increases.

Population based resource allocation: The use of hybrid risk adjustment

The emphasis on integrated care implies new incentives that promote coordinationbetween levels of care. Considering a population as a whole, the resource allocation systemhas to adapt to this environment. This research is aimed to design a model that allows formorbidity related prospective and concurrent capitation payment. The model can be applied inpublicly funded health systems and managed competition settings.Methods: We analyze the application of hybrid risk adjustment versus either prospective orconcurrent risk adjustment formulae in the context of funding total health expenditures for thepopulation of an integrated healthcare delivery organization in Catalonia during years 2004 and2005.Results: The hybrid model reimburses integrated care organizations avoiding excessive risktransfer and maximizing incentives for efficiency in the provision. At the same time, it eliminatesincentives for risk selection for a specific set of high risk individuals through the use ofconcurrent reimbursement in order to assure a proper classification of patients.Conclusion: Prospective Risk Adjustment is used to transfer the financial risk to the healthprovider and therefore provide incentives for efficiency. Within the context of a National HealthSystem, such transfer of financial risk is illusory, and the government has to cover the deficits.Hybrid risk adjustment is useful to provide the right combination of incentive for efficiency andappropriate level of risk transfer for integrated care organizations.

Hybrid risk adjustment for pharmaceutical benefits

This paper analyses the application of hybrid risk adjustment versus either prospective orconcurrent risk adjustment formulae in the context of funding pharmaceutical benefits for thepopulation of an integrated healthcare delivery organization in Catalonia during years 2002 and2003. We apply a mixed formula and find that a hybrid risk adjustment model increasesincentives for efficiency in the provision of low risk individuals at health organizations not only asa whole but also at each internal department compared to only prospective models by reducingwithin-group variation of drug expenditures.

A collagen-poly(lactic acid-co-ɛ-caprolactone) hybrid scaffold for bladder tissue regeneration.

Scaffold materials should favor cell attachment and proliferation, and provide designable 3D structures with appropriate mechanical strength. Collagen matrices have proven to be beneficial scaffolds for tissue regeneration. However, apart from small intestinal submucosa, they offer a limited mechanical strength even if crosslinking can enhance their mechanical properties. A more cell-friendly way to increase material strength is to combine synthetic polymer meshes with plastic compressed collagen gels. This work describes the potential of plastic compressed collagen-poly(lactic acid-co-ɛ-caprolactone) (PLAC) hybrids as scaffolds for bladder tissue regeneration. Human bladder smooth muscle and urothelial cells were cultured on and inside collagen-PLAC hybrids in vitro. Scaffolds were analyzed by electron microscopy, histology, immunohistochemistry, and AlamarBlue assay. Both cell types proliferated in and on the hybrid, forming dense cell layers on top after two weeks. Furthermore, hybrids were implanted subcutaneously in the backs of nude mice. Host cell infiltration, scaffold degradation, and the presence of the seeded bladder cells were analyzed. Hybrids showed a lower inflammatory reaction in vivo than PLAC meshes alone, and first signs of polymer degradation were visible at six months. Collagen-PLAC hybrids have potential for bladder tissue regeneration, as they show efficient cell seeding, proliferation, and good mechanical properties.

Nutrient leaching potential following application of papermill lime-sludge to an acidic clay soil

This experiment was carried out under greenhouse conditions with soil pots during 210 days, to evaluate the effect of calcitic papermill lime-sludge application (at the rates 0, 773, 1.547, and 2.320 mg kg-1 or respective equivalents to control, 2, 4, and 6 t ha-1), on chemical composition of soil leachate and its effects on eucalypt growth and yield. Highest soil leachate pH, SO4, and Na concentrations occurred in the 4 and 6 t ha-1 treatments. Soil leachate nitrate concentrations decreased with increasing lime-sludge rate. Soil leachate phosphate remained low (below the detection limit) in all treatments until 120 days, while the concentration increased in the lime-sludge treatments at 210 days (last sampling) in about 600 mg L-1. Lime-sludge decreased leachate Mg concentration, but had no significant effect among rates. Soil leachate Ca, K, B, Cu, Fe, and Zn did not change significantly for any lime-sludge application rates. The maximum NO3, Ca, Mg, K, and Na concentrations in the soil leachate occurred at 60 days after lime-sludge application (leaching equivalent to 1 pore volume), but for pH and SO4, the maximum occurred at 210 days (leaching equivalent to 4 pore volumes). Lime-sludge application decreased the concentration of exchangeable Al in the soil. Plant diameter growth and dry matter yield were increased with increasing lime-sludge rate. Beneficial effects on mineral nutrition (P, K, Ca, B, and Zn) of eucalypts were also obtained by the application of 4 and 6 t ha-1 of lime-sludge.

Modelling of weather radar echoes from anomalous propagation using a hybrid parabolic equation method and NWP model data

Contamination of weather radar echoes by anomalous propagation (anaprop) mechanisms remains a serious issue in quality control of radar precipitation estimates. Although significant progress has been made identifying clutter due to anaprop there is no unique method that solves the question of data reliability without removing genuine data. The work described here relates to the development of a software application that uses a numerical weather prediction (NWP) model to obtain the temperature, humidity and pressure fields to calculate the three dimensional structure of the atmospheric refractive index structure, from which a physically based prediction of the incidence of clutter can be made. This technique can be used in conjunction with existing methods for clutter removal by modifying parameters of detectors or filters according to the physical evidence for anomalous propagation conditions. The parabolic equation method (PEM) is a well established technique for solving the equations for beam propagation in a non-uniformly stratified atmosphere, but although intrinsically very efficient, is not sufficiently fast to be practicable for near real-time modelling of clutter over the entire area observed by a typical weather radar. We demonstrate a fast hybrid PEM technique that is capable of providing acceptable results in conjunction with a high-resolution terrain elevation model, using a standard desktop personal computer. We discuss the performance of the method and approaches for the improvement of the model profiles in the lowest levels of the troposphere.

Ambient seismic noise monitoring of a clay landslide: Toward failure prediction

Given that clay-rich landslides may become mobilized, leading to rapid mass movements (earthflows and debris flows), they pose critical problems in risk management worldwide. The most widely proposed mechanism leading to such flow-like movements is the increase in water pore pressure in the sliding mass, generating partial or complete liquefaction. This solid-to-liquid transition results in a dramatic reduction of mechanical rigidity in the liquefied zones, which could be detected by monitoring shear wave velocity variations. With this purpose in mind, the ambient seismic noise correlation technique has been applied to measure the variation in the seismic surface wave velocity in the Pont Bourquin landslide (Swiss Alps). This small but active composite earthslide-earthflow was equipped with continuously recording seismic sensors during spring and summer 2010. An earthslide of a few thousand cubic meters was triggered in mid-August 2010, after a rainy period. This article shows that the seismic velocity of the sliding material, measured from daily noise correlograms, decreased continuously and rapidly for several days prior to the catastrophic event. From a spectral analysis of the velocity decrease, it was possible to determine the location of the change at the base of the sliding layer. These results demonstrate that ambient seismic noise can be used to detect rigidity variations before failure and could potentially be used to predict landslides.