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We describe an efficient implementation of cluster perturbation and Møller–Plesset Lagrangian energy series through the fifth order that targets the coupled cluster singles and doubles energy utilizing the resolution of the identity approximation. We illustrate the computational performance of the implementation by performing ground state energy calculations on systems with up to 1200 basis functions using a single node and by comparison to conventional coupled cluster singles and doubles calculations. We further show that our hybrid message passing interface/open multiprocessing parallel implementation that also utilizes graphical processing units can be used to obtain fifth order energies on systems with almost 1200 basis functions with a 90 min "time to solution" running on Frontier at Oak Ridge National Laboratory. [ABSTRACT FROM AUTHOR]

In this paper, we develop and analyze a number of perturbation series that target the coupled cluster singles and doubles (CCSD) ground state energy. We show how classical Møller–Plesset perturbation theory series can be restructured to target the CCSD energy based on a reference CCS calculation and how the corresponding cluster perturbation series differs from the classical Møller–Plesset perturbation series. Subsequently, we reformulate these series using the coupled cluster Lagrangian framework to obtain series, where fourth and fifth order energies are determined only using parameters through second order. To test the methods, we perform a series of test calculations on molecular photoswitches of both total energies and reaction energies. We find that the fifth order reaction energies are of CCSD quality and that they are of comparable accuracy to state-of-the-art approximations to the CCSD energy based on local pair natural orbitals. The advantage of the present approach over local correlation methods is the absence of user defined threshold parameters for neglecting or approximating contributions to the correlation energy. Fixed threshold parameters lead to discontinuous energy surfaces, although this effect is often small enough to be ignored, but the present approach has a differentiable energy that will facilitate derivation and implementation of gradients and higher derivatives. A further advantage is that the calculation of the perturbation correction is non-iterative and can, therefore, be calculated in parallel, leading to a short time-to-solution. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Drowning is the leading cause of death during flood disasters. Little is known about these deaths. Child death review teams review details of child deaths to understand circumstances and risk factors to inform prevention. METHODS: Using data entered in 2005 to 2021 for children ages 0 to 17 years from the National Fatality Review-Case Reporting System, we identified 130 drowning deaths directly attributed to natural disaster or weather incidents, and 14 deaths indirectly attributed to these incidents. Frequencies, proportions, and χ² statistics were used to describe selected measures and compare with other drowning deaths. RESULTS: Children who drowned as a direct result of a natural disaster- or weather-related incident were more likely to be aged >4 years (81% vs 40%, P < .001) and located in a rural or frontier setting (63% vs 30%, P < .001). They were more likely to be supervised at the time of the incident (61% vs 38%, P < .001), and it was more likely for additional children (35% vs 5%, P < .001) or adults (33% vs 3%, P < .001) to have perished. The indirect deaths were commonly a result of damage to protective barriers. CONCLUSIONS: The characteristics of natural disaster- or weather-related drowning deaths among children differ from other drowning deaths. Natural disaster- or weather-related drowning may warrant tailored drowning prevention strategies. Improved surveillance of all water-related deaths may be a proactive action leading to the development of these prevention strategies, whereas poststorm remediation of protective barriers can be used as a reactive prevention after a storm has passed. [ABSTRACT FROM AUTHOR]

We present here a massively parallel implementation of the recently developed CPS(D-3) excitation energy model that is based on cluster perturbation theory. The new algorithm extends the one developed in Baudin et al. [J. Chem. Phys., 150, 134110 (2019)] to leverage multiple nodes and utilize graphical processing units for the acceleration of heavy tensor contractions. Furthermore, we show that the extended algorithm scales efficiently with increasing amounts of computational resources and that the developed code enables CPS(D-3) excitation energy calculations on large molecular systems with a low time-to-solution. More specifically, calculations on systems with over 100 atoms and 1000 basis functions are possible in a few hours of wall clock time. This establishes CPS(D-3) excitation energies as a computationally efficient alternative to those obtained from the coupled-cluster singles and doubles model. [ABSTRACT FROM AUTHOR]

We demonstrate the effectiveness of seismic dense array surface wave focal spot imaging using USArray data from the western‐central United States. We study dispersion in the 60–310 s period range and assess the image quality of fundamental mode Rayleigh wave phase velocity maps. We apply isotropic spatial autocorrelation models to the time domain zero lag noise correlation wavefield data at distances of about one wavelength. Local estimates of the phase velocity, its uncertainty, and the regression quality imply overall better ZZ relative to ZR or RZ results. The extension of the depth resolution compared to passive surface wave tomography is demonstrated by the inversion of three clustered dispersion curves from different tectonic units. We observe anisotropic surface wave energy flux and the influence of body wave energy, but sensitivity tests at 60 s targeting the data range, correlation component, and processing choices show that the ZZ focal spots yield consistent high‐quality images compared to regional tomography results in the 60–150 s period range. In contrast, at 200–300 s the comparatively small scales of the imaged structures and the imperfect agreement with low‐resolution global tomography results highlight the persistent challenge to reconcile imaging results based on different data sources, theories, and techniques. Our study shows that surface wave focal spot imaging is an accurate, robust, local imaging approach. Better control over clean autocorrelation fields can further improve applications of this seismic imaging tool for increased resolution of the elastic structure below dense seismic arrays. Plain Language Summary: Seismic tomography is an established imaging method that estimates properties of the medium using information of the seismic waves that propagate between source and receiver. This concept is routinely applied to earthquake waves and also to waves that are reconstructed using seismic noise correlations, and has led to impressive high‐resolution images in areas with high seismic sensor density. Here we apply an alternative imaging approach that has been developed in ultrasound medical imaging to surface wave data from the dense seismic USArray covering the western‐central part of the contiguous United States. In contrast to tomography the focal spot method does not analyze propagating waves but properties of the spatial autocorrelation field. The seismic wave speed and potentially other medium properties are estimated at the location of each seismic sensor using data obtained at other dense array sensors that are closely spaced in terms of the wavelength. The focal spot imaging technique is elegant and simple to implement because it does not involve the solution of an inverse problem. In this work we demonstrate its effectiveness by reproducing images from available USArray tomography results. Key Points: The local Rayleigh wave speed can be estimated from the focal spot, the time domain spatial noise autocorrelation field at short distancesWe use USArray focal spots to image the elastic velocity structure in the 60−310 s period range and compare the results to tomographyClean seismic dense array focal spots can enhance vertical and lateral resolution and feature detection for improved imaging [ABSTRACT FROM AUTHOR]

We have extended cluster perturbation (CP) theory to comprehend the calculation of first order properties (FOPs). We have determined CP FOP series where FOPs are determined as a first energy derivative and also where the FOPs are determined as a generalized expectation value of the external perturbation operator over the coupled cluster state and its biorthonormal multiplier state. For S(D) orbital excitation spaces, we find that the CP series for FOPs that are determined as a first derivative, in general, in second order have errors of a few percent in the singles and doubles correlation contribution relative to the targeted coupled cluster (CC) results. For a SD(T) orbital excitation space, we find that the CP series for FOPs determined as a generalized expectation value in second order have errors of about ten percent in the triples correlation contribution relative to the targeted CC results. These second order models, therefore, constitute viable alternatives for determining high quality FOPs. [ABSTRACT FROM AUTHOR]

The convergence of the recently developed cluster perturbation (CP) expansions [Pawlowski et al., J. Chem. Phys. 150, 134108 (2019)] is analyzed with the double purpose of developing the mathematical tools and concepts needed to describe these expansions at general order and to identify the factors that define the rate of convergence of CP series. To this end, the CP energy, amplitude, and Lagrangian multiplier equations as a function of the perturbation strength are developed. By determining the critical points, defined as the perturbation strengths for which the Jacobian becomes singular, the rate of convergence and the intruder and critical states are determined for five small molecules: BH, CO, H2O, NH3, and HF. To describe the patterns of convergence for these expansions at orders lower than the high-order asymptotic limit, a model is developed where the perturbation corrections arise from two critical points. It is shown that this model allows for rationalization of the behavior of the perturbation corrections at much lower order than required for the onset of the asymptotic convergence. For the H2O, CO, and HF molecules, the pattern and rate of convergence are defined by critical states where the Fock-operator underestimates the excitation energies, whereas the pattern and rate of convergence for BH are defined by critical states where the Fock-operator overestimates the excitation energy. For the NH3 molecule, both forms of critical points are required to describe the convergence behavior up to at least order 25. [ABSTRACT FROM AUTHOR]

We describe a concise synthetic strategy for the preparation of heterocyclic [9]helicenes and a simple preparative‐scale protocol for the optical resolution of the resulting M‐ and P‐enantiomers. The helicenes were characterized by single‐crystal X‐ray diffraction along with a range of spectroscopic and computational techniques. A fluorescence quantum yield of up to 65 % was observed, and the chiroptical properties of both M‐ and P‐helicenes revealed large dissymmetry factors. The circularly polarized luminescence brightness reaches up to 17 M−1 cm−1, as measured experimentally and verified computationally, which makes this the highest circularly polarized luminescence brightness among heterocyclic helicenes. We describe how chiroptical properties (both circular dichroism and circularly polarized luminescence) can be described and predicted using quantum chemical calculations. The synthetic approach also reveals by‐products that originate from internal oxidation reactions, presumably mediated by the close proximity of the π‐surfaces in the helicene structure. [ABSTRACT FROM AUTHOR]

Photoswitches are molecular systems that are chemically transformed subsequent to interaction with light and they find potential application in many new technologies. The design and discovery of photoswitch candidates require intricate molecular engineering of a range of properties to optimize a candidate to a specific applications, a task which can be tackled efficiently using quantum chemical screening procedures. In this paper, we perform a large scale screening of approximately half a million bicyclic diene photoswitches in the context of molecular solar thermal energy storage using ab initio quantum chemical methods. We further device an efficient strategy for scoring the systems based on their predicted solar energy conversion efficiency and elucidate potential pitfalls of this approach. Our search through the chemical space of bicyclic dienes reveals systems with unprecedented solar energy conversion efficiencies and storage densities that show promising design guidelines for next generation molecular solar thermal energy storage systems. [ABSTRACT FROM AUTHOR]

Photoswitches are molecular systems that are chemically transformed subsequent to interaction with light and they find potential application in many new technologies. The design and discovery of photoswitch candidates require intricate molecular engineering of a range of properties to optimize a candidate to a specific applications, a task which can be tackled efficiently using quantum chemical screening procedures. In this paper, we perform a large scale screening of approximately half a million bicyclic diene photoswitches in the context of molecular solar thermal energy storage using ab initio quantum chemical methods. We further device an efficient strategy for scoring the systems based on their predicted solar energy conversion efficiency and elucidate potential pitfalls of this approach. Our search through the chemical space of bicyclic dienes reveals systems with unprecedented solar energy conversion efficiencies and storage densities that show promising design guidelines for next generation molecular solar thermal energy storage systems. [ABSTRACT FROM AUTHOR]

We analyze envelopes of 233 and 22 ML0.0 to ML1.8 earthquakes induced by two geothermal stimulations in the Helsinki, Finland, metropolitan area. We separate source spectra and site terms and determine intrinsic attenuation and the scattering strength of shear waves in the 3–200 Hz frequency range using radiative transfer based synthetic envelopes. Displacement spectra yield scaling relations with a general deviation from self‐similarity, with a stronger albeit more controversial signal from the weaker 2020 stimulation. The 2020 earthquakes also tend to have a smaller local magnitude compared to 2018 earthquakes with the same moment magnitude. We discuss these connections in the context of fluid effects on rupture speed or medium properties. Site terms demonstrate that the spectral amplification relative to two reference borehole sites is not neutral at the other sensors; largest variations are observed at surface stations at frequencies larger than 30 Hz. Intrinsic attenuation is exceptionally low with Qi−1 ${Q}_{\mathrm{i}}^{-1}$ values down to 2.4 × 10−5 at 20 Hz, which allows the observation of a diffuse reflection at the ∼50 km deep Moho. Scattering strength is in the range of globally observed data with Qsc−1 ${Q}_{\mathrm{s}\mathrm{c}}^{-1}$ between 10−3 and 10−4. The application of the employed Qopen analysis program to the 2020 data in a retrospective monitoring mode demonstrates its versatility as a seismicity processing tool. The diverse results have implications for scaling relations, hazard assessment and ground motion modeling, and imaging and monitoring using ballistic and scattered wavefields in the crystalline Fennoscandian Shield environment. Plain Language Summary: We analyze seismograms from earthquakes that were induced during two geothermal stimulation experiments in the Helsinki, Finland, metropolitan area, in 2018 and 2020. We process long signals including later parts of the seismograms to solve the persistent problem of separating the effects of the earthquake source process, of the bedrock, and of the ground immediately below a seismic sensor on the observed data. The high data quality allows us to measure systematic differences in some fundamental earthquake source parameters between events induced during the two stimulations. We attribute this to the effect of the fluids that were pumped into the 6 km deep rock formations. These observations are important since natural earthquakes and earthquakes induced by such underground engineering activities are governed by the same physical mechanisms. We also find that the bedrock in southern Finland is characterized by some of the lowest seismic attenuation values that have so far been measured in different tectonic environments. Last, the so‐called site effects at the instrument locations show a diverse amplification pattern in a wide frequency range, which is important for the assessment of shaking scenarios in the area. Key Points: We find lower stress drop values for events induced by the 2020 compared to the 2018 stimulation and a deviation from self‐similar scalingThe observation of a diffuse reflection at the 50 km deep Moho highlights the low intrinsic attenuation in the Fennoscandian ShieldSite effect terms between 3 and 200 Hz show diverse frequency and site dependent patterns with high‐frequency amplification [ABSTRACT FROM AUTHOR]

Photoswitch triads comprising two dihydroazulene (DHA) units in conjugation with a central trans‐azobenzene (AZB) unit were prepared in stepwise protocols starting from meta‐ and para‐disubstituted azobenzenes. The para‐connected triad had significantly altered optical properties and lacked the photoactivity of the separate photochromes. In contrast, for the meta‐connected triad, all three photochromes could be photoisomerized to generate an isomer with two vinylheptafulvene (VHF) units and a cis‐azobenzene unit. Ultrafast spectroscopy of the photoisomerizations revealed a fast DHA‐to‐VHF photoisomerization and a slower trans‐to‐cis AZB photoisomerization. This meta triad underwent thermal VHF‐to‐DHA back‐conversion with a similar rate of all VHFs, independent of the identity of the neighboring units, and in parallel thermal cis‐to‐trans AZB conversion. The experimental observations were supported by computation (excitation spectra and orbital analysis of the transitions). [ABSTRACT FROM AUTHOR]

We estimate vertical rotation rates for 204 earthquakes that were induced by the 2018 stimulation of the Espoo/Helsinki geothermal reservoir from wavefield gradients across geophone arrays. The array‐derived rotation rates from seismograms recorded at 6–9 km hypocentral distances vary between 10−9 and 10−7 rad s−1, indicating a comparable sensitivity to portable rotational instruments. Using co‐located observations of translational and rotational motion, we estimate the local propagation direction and the apparent phase speed of SH waves, and compare these estimates with those obtained by S wave beamforming. Propagation directions generally align with the earthquake back azimuths, but both techniques show deviations indicative of heterogeneous seismic structure. The rotational method facilitates a station‐by‐station approach that resolves site specific variations that are controlled by the local geology. We measure apparent S wave speeds larger than 5 km s−1, consistent with steep incidence angles and high propagation velocities in the Fennoscandian Shield. Plain Language Summary: Earthquakes generate seismic waves consisting of both translational (back‐and‐forth) and rotational ground motion. Translational motion is routinely measured by standard seismometers, but the observation of the rotational motion requires relatively expensive and rare instruments. In this study we estimate rotational ground motion caused by earthquakes using groups of translational seismometers. The computation of rotational motion from translational seismometers has been demonstrated before, but the novelty of our study is to use high‐quality recordings of earthquakes that were induced by the creation of a geothermal reservoir at 6 km depth in bedrock. We use our measurements of ground rotation to estimate the speed and direction in which the seismic waves are travelling when they reach the seismometers. We find that the direction in which the seismic waves travel usually points back to the earthquake location, but at some seismometers the waves arrive from a different direction. At these locations, it is likely that local geological features are altering the direction of the waves. We expect that our findings will provide access to approaches for determining earthquake characteristics and Earth structure that currently require highly specialized instruments. Key Points: Wavefield gradiometry is applied to arrays of translational seismometers to estimate rotational motions from induced earthquakesHigh‐quality records of M0.0 to M1.8 events obtained within 10 km hypocentral distance facilitate array‐based resolution of rotation ratesThe obtained apparent phase speed and wave propagation directions are linked to subsurface structure [ABSTRACT FROM AUTHOR]

The aim of this study was to describe the circumstances surrounding firework-related deaths in Denmark, locate similarities and compare findings to the other known literature. Autopsy files, including police reports, located through searches in the archives of the three Danish institutes of forensic medicine were accessed. Data describing the age, gender, toxicology findings, circumstances of the accident, cause of death, autopsy findings and type of fireworks were examined. Eight cases involving firework-related deaths matched the search criteria, two of which occurred on New Year's Eve. An unknown number of cases that had not been autopsied were confirmed to exist. Data from the included cases suggested that using illegal fireworks, being male and handling fireworks directly played a key role in deaths. Most notably, illegal fireworks account for few injuries overall but caused the most deaths found in this study. Firework-related deaths are a rare occurrence. Autopsy findings often reveal blast wave injury to be the cause of death. Only one of the eight decedents included in this study were intoxicated with alcohol. Thus it can be assumed that powerful illegal fireworks are, by themselves, a risk factor for a deadly accident, independent of alcohol intoxication. [ABSTRACT FROM AUTHOR]

Obesity is a preventable risk factor for breast cancer following menopause. Regardless of menopausal status, obese women who develop breast cancer have a worsened prognosis. Breast tissue is comprised of mammary epithelial cells organized into ducts and lobules and surrounded by adipose-rich connective tissue. Studies utilizing multiple in vivo models of obesity as well as human breast tissue have contributed to our understanding of how obesity alters mammary tissue. Localized changes in mammary epithelial cell populations, elevated secretion of adipokines and angiogenic mediators, inflammation within mammary adipose tissue, and remodeling of the extracellular matrix may result in an environment conducive to breast cancer growth. Despite these significant alterations caused by obesity within breast tissue, studies have suggested that some, but not all, obesity-induced changes may be mitigated with weight loss. Here, we review our current understanding regarding the impact of obesity on the breast microenvironment, how obesity-induced changes may contribute to breast tumor progression, and the impact of weight loss on the breast microenvironment. [ABSTRACT FROM AUTHOR]

We study temporal changes of seismic velocities associated with the 10 June 2016 M w 5.2 Borrego Springs earthquake in the San Jacinto fault zone, using nine component Green's function estimates reconstructed from daily cross correlations of ambient noise. The analysed data are recorded by stations in two dense linear arrays, at Dry Wash (DW) and Jackass Flat (JF), crossing the fault surface trace ∼3 km northwest and southeast of the event epicentre. The two arrays have 9 and 12 stations each with instrument spacing of 25–100 m. Relative velocity changes (δv / v) are estimated from arrival time changes in the daily correlation coda waveforms compared to a reference stack. The obtained array-average δv / v time-series exhibit changes associated with the Borrego Springs event, superposed with seasonal variations. The earthquake-related changes are characterized by a rapid coseismic velocity drop followed by a gradual recovery. This is consistently observed at both arrays using time- and frequency-domain δv / v analyses with data from different components in various frequency bands. Larger changes at lower frequencies imply that the variations are not limited to the near surface material. A decreasing coseismic velocity reduction with coda wave lapse time indicates larger coseismic structural perturbations in the fault zone and near-fault environment compared to the surrounding rock. Observed larger changes at the DW array compared to the JF array possibly reflect the northwestward rupture directivity of the Borrego Springs earthquake. [ABSTRACT FROM AUTHOR]

We present a new method for estimating time-series of relative seismic velocity changes (dv/v) within the Earth. Our approach is a Markov chain Monte Carlo (MCMC) technique that seeks to construct the full posterior probability distribution of the dv/v variations. Our method provides a robust, computationally efficient way to compute dv/v time-series that can incorporate information about measurement uncertainty, and any prior constraints that may be available. We demonstrate the method with a synthetic experiment, and then apply the MCMC algorithm to three data examples. In the first two examples we reproduce dv/v time-series associated with the response to the 2010 M 7.2 El Mayor-Cucapah earthquake at two sites in southern California, that have been studied in previous literature. In the San Jacinto fault zone environment we reproduce the dv/v signature of a deep creep slip sequence triggered by the El Mayor-Cucapah event, that is superimposed on a strong seasonal signal. At the Salton Sea Geothermal Field we corroborate the previously observed drop-and-recovery in seismic velocity caused by ground shaking related to the El Mayor-Cucapah event. In a third, new example we compute a month long velocity change time-series at hourly resolution at Piñon Flat, California. We observe a low amplitude variation in seismic velocity with a dominant frequency of 1 cycle per day, as well as a second transient signal with a frequency of 1.93 cycles per day. We attribute the 1-d periodicity in the dv/v variation to the combined effects of the diurnal tide and solar heating. The frequency of the signal at 1.93 cycles per day matches that of the lunar (semi-diurnal) tide. Analysis of the uncertainties in the Piñon Flat time-series shows that the error contains a signal with a frequency of 1 cycle per day. We attribute this variation to seismic noise produced by freight trains operating within the Coachella Valley. By demonstrating the applicability of the MCMC method in these examples, we show that it is well suited to tackle problems involving large data volumes that are typically associated with modern seismic experiments. [ABSTRACT FROM AUTHOR]

Herein, we report monomeric and dimeric norbornadiene‐quadricyclane molecular photoswitch systems intended for molecular solar thermal applications. A series of six new norbornadiene derivatives conjugated with benzothiadiazole as the acceptor unit and dithiafulvene as the donor unit were synthesized and fully characterized. The photoswitches were evaluated by experimentally and theoretically measuring optical absorption profiles and thermal conversion of quadricyclane to norbornadiene. Computational insight by density functional theory calculations at the M06‐2X/def2‐SVPD level of theory provided geometries, storage energies, UV‐vis absorption spectra, and HOMO‐LUMO levels that are used to describe the function of the molecular systems. The studied molecules exhibit absorption onset ranging from 416 nm to 595 nm due to a systemic change in their donor‐acceptor character. This approach was advantageous due to the introduction of benzothiadiazole and the dimeric nature of molecular structures. The best‐performing system has a half‐life of 3 days with quantum yields over 50 %. [ABSTRACT FROM AUTHOR]

We study temporal changes of seismic velocity (dv/v) in the crust around the central section of the San Jacinto fault zone (SJFZ), Southern California. Focusing on a 200‐day‐long period around April 2010, our analysis resolves two tens‐of‐days‐long successive episodes of reduced velocities that are compatible with signals from the long base strainmeter at the Piñon Flat Observatory. The imaged dv/v sequences are proxies for evolving material properties in the crust surrounding the SJFZ. The temporal and the spatial coincidence of the observed dv/v patterns with the occurrence of two proposed creep episodes suggest that the relative velocity changes reflect the response to deep creep events that follow the M7.2 El Mayor‐Cucapah earthquake and the M5.4 Collins Valley earthquake that occurred 94 days later on the San Jacinto fault. The main slip during the creep events was proposed to occur below 10‐km depth. Wavefield properties suggest sensitivity to medium changes above this source zone, in the top 10 km. The distribution of the obtained dv/v reductions shows a strong difference between large values to the west of the SJFZ and significantly smaller amplitudes to the east. The similarity to the seasonal velocity change pattern implies that the results are likely controlled by the contrast of mechanical properties across the fault, such as fault‐perpendicular shear modulus variations. Our analysis extends the spectrum of methods that can be used to study earthquake interaction, fault zone rheology and dynamics, triggering, and the interplay between creep episodes and earthquakes. Plain Language Summary: Motion along geologic fault zones not only occurs during small and large potentially devastating earthquakes. Some faults creep aseismically, which means the slip motion is too slow to generate earthquake waves. To develop a more complete understanding of fault behavior, it is important to detect and locate such creep transients. A particularly interesting problem is how earthquakes and episodic creep events, which tend to occur in a zone below the earthquakes, interact with each other. Creep events are usually detected using satellite‐based methods. In this study we applied the most modern ambient seismic wavefield analysis techniques to first detect and locate changes in the rock properties around a continental strike slip fault, the San Jacinto fault, Southern California, that are caused by two successive deep creep events along that fault. These results are supported by data from a colocated deformation meter that picked up signals from the same creep events that are thought to be triggered, initiated by the two earthquakes indicated in the title. The observed deformation patterns—they are not uniform along and across the fault—and their temporal evolution can help us better understand the processes that happen on and off faults in earthquake‐prone regions. Key Points: We observe seismic velocity change patterns that vary along and across the San Jacinto fault zoneThe time and frequency dependence of the changes suggests an upward migrating deformation patternTogether with strainmeter signals these results indicate a response to two deep creep events [ABSTRACT FROM AUTHOR]

In this paper, an analytical method to model the thermal resistance of windings made either of solid or litz wire is presented and validated by measurements. In addition, an extended numerical approach for litz wire windings, which also considers the twist pitch, is shown. With the presented model, it is possible to describe the thermal resistance of arbitrary wire arrangements. This approach can be used in straightforward thermal designs of magnetic devices, or it can be integrated in optimization procedures to improve the thermal designs of magnetic components. The analytical models are verified by measurements with nonpotted and epoxy-potted solid wire test setups and test setups for litz wire, which all show a good matching between the calculated and measured values. Besides the models for the thermal resistance between the winding layers, a method to simplify the thermal network of multilayer windings is presented. Finally, a thermal equivalent circuit of a test transformer has been calculated, which shows a good match between the measured and the predicted temperature distribution. [ABSTRACT FROM AUTHOR]

We have extended cluster perturbation (CP) theory to comprehend the Lagrangian framework of coupled cluster (CC) theory and derived the CP Lagrangian energy series (LCP) where the 2n + 1/2n + 2 rules for the cluster amplitudes and multipliers are used to get the energy corrections. We have also developed the variational CP ( L C P ) series, where the total cluster amplitudes and multipliers are determined through the same orders as in the LCP series, but the energy is obtained by inserting the total cluster amplitudes and multipliers in the Lagrangian. The energies of the L C P series have errors that are bilinear in the errors of the total cluster amplitudes and multipliers. Test calculations have been performed for S(D) and SD(T) orbital excitation spaces. With the exception of molecular systems that have a low lying doubly excited state compared to the electronic ground state configuration, we find that the fourth order models L C P S (D−4), L C P S D (T−4), and LCPSD(T−4) give energies of CC target state quality. For the L C P S (D−4) model, CC target state quality is obtained as the L C P S (D−4) calculation determines more than 99.7% of the coupled cluster singles and doubles (CCSD) correlation energy as the numerical deviations of the L C P S (D−4) energy from the CCSD energy were more than an order of magnitude smaller than the triples correlation contribution. For the L C P S D (T−4) and LCPSD(T−4) models, CC target state quality was obtained, given that the L C P S D (T−4) and LCPSD(T−4) calculations recover more than 99% of the coupled cluster singles doubles and triples (CCSDT) correlation contribution and as the numerical deviations of the L C P S D (T−4) and LCPSD(T−4) energies from the CCSDT energy were nearly and order of magnitude smaller than the quadruples correlation contribution. We, thus, suggest that the fourth order models may replace the full target CC models with no or very limited loss of accuracy. [ABSTRACT FROM AUTHOR]

The contribution of protected areas to biodiversity conservation is well attested but many taxa in many regions remain dependent on the unprotected wider landscape. To develop conservation plans for large mammals such as the Endangered pygmy hippopotamus Choeropsis liberiensis of West Africa's Upper Guinea Forests it is critical to understand the importance of unprotected land. Despite being a conservation priority, little is known about the habitat associations of this species, or its distribution across its range. Through a combination of field surveys, species distribution models and community questionnaires we investigated the use of unprotected areas by the pygmy hippopotamus in the Sierra Leone–Liberia border region. We found signs of the species in 128 of 525 1-km2 cells surveyed. Our analysis suggested that the species is reasonably widespread in this region and is associated with major rivers. It occurred close to, but rarely within, large areas of intact forest, and 80.4% of pygmy hippopotamus signs were recorded outside protected areas. The expansion of the protected area network in this area is unrealistic in Sierra Leone and to some extent in Liberia, mainly because of anthropogenic pressure and the overlap of proposed protected areas with mining and logging concessions. Thus pygmy hippopotamus conservation activities in the region need to include programmes on community lands while maintaining a robust network of protected forests. Community-based conservation of the pygmy hippopotamus may prove valuable for other threatened and endemic species that are not confined to protected areas in this region. [ABSTRACT FROM PUBLISHER]

Seismic wavefields interact with low-velocity fault damage zones. Waveforms of ballistic fault zone head waves, trapped waves, reflected waves and signatures of trapped noise can provide important information on structural and mechanical fault zone properties. Here we extend the class of observable fault zone waves and reconstruct in-fault reverberations or multiples in a strike-slip faulting environment. Manifestations of the reverberations are significant, consistent wave fronts in the coda of cross-correlation functions that are obtained from scattered earthquake waveforms and seismic noise recorded by a linear fault zone array. The physical reconstruction of Green's functions is evident from the high similarity between the signals obtained from the two different scattered wavefields. Modal partitioning of the reverberation wavefield can be tuned using different data normalization techniques. The results imply that fault zones create their own ambiance, and that the here reconstructed reverberations are a key seismic signature of wear zones. Using synthetic waveform modelling we show that reverberations can be used for the imaging of structural units by estimating the location, extend and magnitude of lateral velocity contrasts. The robust reconstruction of the reverberations from noise records suggests the possibility to resolve the response of the damage zone material to various external and internal loading mechanisms. [ABSTRACT FROM AUTHOR]

We observe seasonal seismic wave speed changes (dv/v) in the San Jacinto fault area and investigate several likely source mechanisms. Velocity variations are obtained from analysis of 6 yr data of vertical component seismic noise recorded by 10 surface and six borehole stations.We study the interrelation between dv/v records, frequency-dependent seismic noise properties, and nearby environmental data of wind speed, rain, ground water level, barometric pressure and atmospheric temperature. The results indicate peak-to-peak seasonal velocity variations of ∼0.2 per cent in the 0.5-2 Hz frequency range, likely associated with genuine changes of rock properties rather than changes in the noise field. Phase measurements between dv/v and the various environmental data imply that the dominant source mechanism in the arid study area is thermoelastic strain induced by atmospheric temperature variations. The other considered environmental effects produce secondary variations that are superimposed on the thermal-based changes.More detailed work with longer data on the response of rocks to various known external loadings can help tracking the evolving stress and effective rheology at depth. [ABSTRACT FROM AUTHOR]

This article describes the acquisition by Harvard University's library of a print of Robert Flaherty's short 1934 film in the Irish language, Oidhche Sheanchais (A night of storytelling), the apparent disappearance of all copies of the film after 1943, the rediscovery of Harvard's copy in 2012, and the restoration process that has ensued. The authors discuss the song and the maritime legend at the heart of the film, as well as the film's significance as an early ethnodocumentary. The Appendix provides, for the first time, the text of the film's soundtrack, with full English translation. [ABSTRACT FROM AUTHOR]

Abstract: Using seismic noise based monitoring techniques we find that seismic velocity variations ( ) observed with the borehole array of the Taiwan Chelungpu-fault Drilling Project (TCDP) are controlled by strong precipitation events associated with the Madden–Julian Oscillation (MJO), a dynamic intraseasonal atmospheric pattern in the tropical atmosphere. High-frequency noise (>1 Hz) excited by steady anthropogenic activity in the vicinity of the TCDP allows daily resolution of time series. Relatively large fluid discharge properties control the equilibration of the ground water table and hence seismic velocities on time scales smaller than the average precipitation recurrence interval. This leads to the observed synchronous 50–80 day periodicity in and rainfall records in addition to the dominant annual component. Further evidence for the governing role of hydraulic properties is inferred from the similarity of observed timing, amplitude, and recovery properties with synthetics generated by a combined model of ground water table changes and diffusive propagation of seismic energy. The lapse time (τ) dependent increase of amplitudes is controlled by the sensitivity of the diffuse wave field sampled at 1100 m depth to shallower water level fluctuations. The significant vertical offset between stations and water level explains the direct τ dependence which is opposite to the trend previously inferred from measurements at the surface. [Copyright &y& Elsevier]

We show that noise amplitudes at frequencies above 1 Hz exhibit strong seasonal variations in a broad southern California region. The results are based on 3-component seismic data recorded between 2002 and 2009 by 30 stations. Focusing on continuous 6-hr night-time segments, the seismograms are bandpass-filtered in nine frequency bands between 2 and 18 Hz. Squared amplitudes are median-filtered to reduce the influence of earthquake signals and integrated to yield half-hourly noise energy estimates. The 6-hr minimum energy values are converted back to ground velocity and used as representative daily noise level amplitudes. Notwithstanding various trends, drifts and other transient complexities, a common feature of the resulting time series in both the horizontal and vertical components are annual amplitude changes at all examined frequencies and all stations. The strength of amplitude variations shows no correlation with distance from the coast and some particularly clear seasonal changes are seen near topographic features in arid uninhabited areas. Comparison to meteorological data suggests that the main sources for the high-frequency noise field are variations of temperature and wind at the surface. In addition to acting directly on topographic irregularities and other surface features, these sources (and especially temperature changes) may also generate high-frequency noise by inducing multitudinous small-scale failures in the shallow crust. [ABSTRACT FROM AUTHOR]

Observations from laboratory, field and numerical work spanning a wide range of space and time scales suggest a strain dependent progressive evolution of material properties that control the stability of earthquake faults. The associated weakening mechanisms are counterbalanced by a variety of restrengthening mechanisms. The efficiency of the healing processes depends on local material properties and on rheologic, temperature, and hydraulic conditions. We investigate the relative effects of these competing non-linear feedbacks on seismogenesis in the context of evolving frictional properties, using a mechanical earthquake model that is governed by slip weakening friction. Weakening and strengthening mechanisms are parametrized by the evolution of the frictional control variable—the slip weakening rate R—using empirical relationships obtained from laboratory experiments. In our model, weakening depends on the slip of an earthquake and tends to increase R, following the behaviour of real and simulated frictional interfaces. Healing causes R to decrease and depends on the time passed since the last slip. Results from models with these competing feedbacks are compared with simulations using non-evolving friction. Compared to fixed R conditions, evolving properties result in a significantly increased variability in the system dynamics. We find that for a given set of weakening parameters the resulting seismicity patterns are sensitive to details of the restrengthening process, such as the healing rate b and a lower cutoff time, , up to which no significant change in the friction parameter is observed. For relatively large and small cutoff times, the statistics are typical of fixed large and small R values, respectively. However, a wide range of intermediate values leads to significant fluctuations in the internal energy levels. The frequency-size statistics of earthquake occurrence show corresponding non-stationary characteristics on time scales over which negligible fluctuations are observed in the fixed- R case. The progressive evolution implies that—except for extreme weakening and healing rates—faults and fault networks possibly are not well characterized by steady states on typical catalogue time scales, thus highlighting the essential role of memory and history dependence in seismogenesis. The results suggest that an extrapolation to future seismicity occurrence based on temporally limited data may be misleading due to variability in seismicity patterns associated with competing mechanisms that affect fault stability. [ABSTRACT FROM AUTHOR]

Habitat degradation alters the dynamics and composition of anuran assemblages in tropical forests. The effects of forest fragmentation on the composition of anuran assemblages are so far poorly known. We studied the joint influence of forest fragmentation and degradation on leaf-litter frogs. We specifically asked whether the processes structuring leaf-litter anuran assemblages in fragmented forests are the same as those in continuous forests. We analyzed anuran assemblages with respect to habitat characteristics, including fragmentation and degradation parameters. In comparison with continuous forests, species richness and diversity were lower and assemblage composition was altered in forest fragments. These changes seemed to be mainly caused by habitat degradation rather than forest fragmentation. Availability of aquatic sites for breeding, vegetation structure (including those variables indicating degradation), and leaf-litter cover had the most influence on the presence of single species. The comparatively small impact of fragmentation on anurans might be due to the location of the study area; it still possessed large tracts of continuous forest. These forest blocks may stabilize the regional rainforest climate and thus weaken the effects of fragmentation. [ABSTRACT FROM AUTHOR]

We perform a systematic parameter space study of the seismic response of a large fault with different levels of heterogeneity, using a 3-D elastic framework within the continuum limit. The fault is governed by rate-and-state friction and simulations are performed for model realizations with frictional and large scale properties characterized by different ranges of size scales. We use a number of seismicity and stress functions to characterize different types of seismic responses and test the correlation between hypocenter locations and the employed distributions of model parameters. The simulated hypocenters are found to correlate significantly with small L values of the rate-and-state friction. The final sizes of earthquakes are correlated with physical properties at their nucleation sites. The obtained stacked scaling relations are overall self-similar and have good correspondence with properties of natural earthquakes. [ABSTRACT FROM AUTHOR]

Using classical ex situ techniques (optical microscopy, Raman spectroscopy), differential scanning calorimetry, and two new in situ techniques for characterization during crystallization (high-temperature environmental scanning electron microscopy and high-temperature X-ray diffraction with a fast detector), the addition of B2O3 to SiO2–Al2O3–CaO glasses was examined to understand its impact on crystallization behavior. The conventional ex situ characterization reveals that B2O3 addition reduces crystal growth rate and also decreases the liquidus temperature. The in situ techniques provide complementary information on the crystallization kinetics. [ABSTRACT FROM AUTHOR]

A range of observations suggest the formation and maintenance of sealed and hence overpressured compartments in fluid-infiltrated fault zones. It is assumed that hydromechanical properties of regions with variable pore pressure states control the fault's stability and thus its characteristic response, that is, seismic or aseismic slip accumulation. We investigate in a systematic parameter space study the effects of spatial variations in pore pressure on spatiotemporal slip evolution along a hydraulically isolated fault plane. The 3-D continuum model is governed by rate-and-state friction and constitutive laws for porosity reduction. We show that the model response is sensitive to the degree of overpressurization and the efficiency of dilatant hardening mechanisms. Low pore pressures and small dilatancy effects result in unstable response types, whereas high pore pressures and large dilatant effects lead to stable and aseismic creep. Regions with an unstable response are shown to support most of the stresses accumulated during interseismic periods. Accelerated slip nucleates preferably in regions of low pore pressure. Statistical properties of model seismicity produce a wide range of event sizes for moderate and large earthquakes, in the case where dilatant mechanisms are inefficient. In case of efficient slip rate controlled porosity increase, less instabilities grow into large earthquakes. Final slip maps demonstrate the applicability of the chosen method to model seismicity controlled by frictional and hydraulic processes on a planar fault plane. The evolution of governing variables that depend on the pore pressure environment provide a conceptual basis for the interpretation of observed response characteristics. [ABSTRACT FROM AUTHOR]

The Special Unit of Psychological Attention at SUMMA 112 carried out a medium-term follow-up survey with a 185 victims sample three months after the terrorist attacks on 11th March 2004 in Madrid. The results are presented in this paper. A protocol designed ad hoc by the Unit and TOP-8 scale were administered by telephone. During the follow-up 54 percent of the victims sample (64 percent women) showed probable Posttraumatic Stress Disorder. 34 percent of victims received mental assistance one week after the terrorist attacks. A high number of respondents (83 percent) indicated a reduction of their initial symptoms during the survey, those which urged them to call SUMMA 112 emergency numbers in the first moments after the attacks. These results show the consequences on victims of a traumatic event and the relevance of immediate and close assistance in psychological crisis intervention in order to diminish the negative effects. [ABSTRACT FROM AUTHOR]

The paper describes the creation and activities undertaken by the Special Unit for Psychological Attention set up within Madrid's Emergency Medical Services (SUMMA 112) after the terrorist attacks in Madrid on the 11th of March, 2004. In addition, it describes psychological crisis interventions carried out by the Unit, both by telephone and at home, based on the principles of immediacy and close assistance. A follow-up protocol was also designed. This protocol was administered 3 months after the attacks to a sample of 250 subjects who had previously requested psychological assistance at the Unit. The initial results show that 64% of the direct victims suffered Postraumatic Stress Disorder. [ABSTRACT FROM AUTHOR]

Aging is associated with loss of the physical barriers and immune efficiency that typically control pathogens' access to and multiplication within the body, thus making infection more likely in elderly persons. Chronic diseases and other health factors, such as malnutrition and immobility, may increase susceptibility to and severity of infections, including foodborne illnesses, in elderly persons, as well as associated morbidity and mortality. Prevention is the best way to avoid foodborne illnesses, but older adults have long-established food preparation and handling practices, some of which may increase the likelihood of illness. Elderly persons rely on physicians as trusted sources of health information. Physicians and other health care professionals can help prevent and control foodborne diseases by educating their patients about the risks of foodborne illness, providing sound advice on safe food-handling and consumption practices, making rapid appropriate diagnoses, and reporting cases promptly to public health authorities. [ABSTRACT FROM AUTHOR]

Objective—To determine the incidence of regional lymph node metastasis in dogs with appendicular osteosarcoma and determine whether regional lymph node metastasis was associated with shortened disease-free interval or survival time. Design—Retrospective study. Animals—228 dogs with appendicular osteosarcoma in which regional lymph nodes were examined histologically at the time of limb amputation. Procedure—Information collected from the medical records included signalment; affected site; initial serum alkaline phosphatase activity; whether treatment involved adjuvant chemotherapy and, if so, chemotherapeutic agents administered and number of treatments; disease-free interval; and survival time. Results—10 (4.4%) dogs had histologic evidence of regional lymph node metastasis at the time of amputation. Median disease-free interval for dogs without regional lymph node metastasis (238 days; range, 0 to 1,067 days) was significantly longer than median disease-free interval for dogs with regional lymph node metastasis (48 days; range, 2 to 269 days). Median survival time for dogs without lymph node metastasis (318 days; range, 20 to 1,711 days) was significantly longer than median survival time for dogs with lymph node metastasis (59 days; range, 19 to 365 days). Conclusions and Clinical Relevance—Results suggest that regional lymph node metastasis is rare in dogs with appendicular osteosarcoma but that dogs with lymph node metastasis have a poorer prognosis than do dogs without. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The objective of this study was to design and develop food safety knowledge and attitude scales based on food-handling guidelines developed by a national panel of food safety experts. Design: Knowledge (n=43) and attitude (n=49) questions were developed and pilot-tested with a variety of consumer groups. Final questions were selected based on item analysis and on validity and reliability statistical tests. Subjects/setting: Knowledge questions were tested in Washington State with participants in low-income nutrition education programs (pretest/posttest n=58, test/retest n=19) and college students (pretest/posttest n=34). Attitude questions were tested in Ohio with nutrition education program participants (n=30) and college students (non-nutrition majors n=138, nutrition majors n=57). Statistical analyses performed: Item analysis, paired sample t tests, Pearson’s correlation coefficients, and Cronbach’s α were used. Results: Reliability and validity tests of individual items and the question sets were used to reduce the scales to 18 knowledge questions and 10 attitude questions. The knowledge and attitude scales covered topics ranked as important by a national panel of experts and met most validity and reliability standards. The 18-item knowledge questionnaire had instructional sensitivity (mean score increase of more than three points after instruction), internal reliability (Cronbach’s α >.75), and produced similar results in test-retest without intervention (coefficient of stability=.81). Knowledge of correct procedures for hand washing and avoiding cross-contamination was widespread before instruction. Knowledge was limited regarding avoiding food preparation while ill, cooking hamburgers, high-risk foods, and whether cooked rice and potatoes could be stored at room temperature. The 10-item attitude scale had an appropriate range of responses (item difficulty) and produced similar results in test-retest (P≤.01). Internal consistency ranged from α=.63 to .89. Students anticipating a career where food safety is valued had higher attitude scale scores than participants of extension education programs. Conclusions: Uses for the knowledge questionnaire include assessment of subject matter knowledge before instruction and knowledge gain after instruction. The attitude scale assesses an outcome variable that may predict food safety behavior. [Copyright &y& Elsevier]

To be effective in reducing the incidence of foodborne illness, consumers and food safety educators need information about behaviors that will decrease exposure to foodborne pathogens. A four-round Delphi technique was used to survey nationally recognized experts in food microbiology, epidemiology, food safety education, and food safety policy with the aim of identifying and ranking food-handling and consumption behaviors associated with 13 major foodborne pathogens. The food safety experts ranked behaviors related to keeping foods at safe temperatures as of primary importance in preventing illness caused by Bacillus cereus and Clostridium perfringens and of secondary importance in preventing illness caused by Staphylococcus aureus. The use of a thermometer to cook foods adequately was ranked as of primary importance for the prevention of illness caused by Campylobacter jejuni, Salmonella species, Escherichia coli O157:H7, Toxoplasma gondii, and Yersinia enterocolitica, with the avoidance of cross-contamination being ranked as of secondary importance for most of these pathogens. Hand washing was the top-ranked behavior for the prevention of shigellosis. The avoidance of certain foods that are likely to be contaminated was the top-ranked behavior for the prevention of illnesses caused by Listeria monocytogenes, Noroviruses, and Vibrio species. The expert panel's ranking of behaviors for the reduction of the risk of illness caused by major foodborne pathogens can enable consumers to make informed choices about food consumption and handling behaviors and can guide food safety educators in prioritizing their educational efforts. [ABSTRACT FROM AUTHOR]

A central event in sexual reproduction is the reduction in chromosome number that occurs at the meiosis I division. Most eukaryotes rely on crossing over between homologs, and the resulting chiasmata, to direct meiosis I chromosome segregation, yet make very few crossovers per chromosome pair . This indicates that meiotic recombination must be tightly regulated to ensure that each chromosome pair enjoys the crossover necessary to ensure correct segregation. Here, we investigate control of meiotic crossing over in Caenorhabditis elegans, which averages only one crossover per chromosome pair per meiosis , by constructing genetic maps of end-to-end fusions of whole chromosomes. Fusion of chromosomes removes the requirement for a crossover in each component chromosome segment and thereby reveals a propensity to restrict the number of crossovers such that pairs of fusion chromosomes composed of two or even three whole chromosomes enjoy but a single crossover in the majority of meioses. This regulation can operate over physical distances encompassing half the genome. The meiotic behavior of heterozygous fusion chromosomes further suggests that continuous meiotic chromosome axes, or structures that depend on properly assembled axes, may be important for crossover regulation. [Copyright &y& Elsevier]

Discusses the core meiotic recombination machinery that leads to the development of sexual reproduction in eukaryotes. Regeneration of the diploid chromosome complement in the subsequent generation; Assembly of the synaptonemal complex; Formation of crossovers in large chromosome segments.

Traditionally, nutrition educators have used a fairly global approach to teach food safety by teaching a broad range of safe food handling behaviors in the expectation that this will lead to the avoidance of foodborne illness. This approach can be confusing and lead to evaluation data that are difficult to interpret. This article suggests that food safety education and evaluation in the future be organized around five behavioral constructs: practice personal hygiene, cook foods adequately, avoid cross-contamination, keep foods at safe temperatures, and avoid food from unsafe sources. These five constructs are derived from data on actual outbreaks and estimated incidences of foodborne illness. Research is needed to establish reliable and valid evaluation measures for these five behavioral constructs. Evaluation instruments can be tailored to fit specific education programs. If evaluation instruments focus on these five behavior areas, the result will be meaningful evaluation data that can be more easily summarized across food safety education programs for consumers. [ABSTRACT FROM AUTHOR]

Examines food safety education programs aimed at decreasing the risk of foodborne diseases among consumers. Five major control factors for pathogens; Incidence of foodborne diseases; Consumer behaviors regarding food handling at home.

(1) Background: Altered levels of autoantibodies (aab) and their networks have been identified as biomarkers for various diseases. Neovascular age-related macular degeneration (nAMD) is a leading cause for central vision loss worldwide with highly variable inter- and intraindividual disease courses. Certain aab networks could help in daily routine to identify patients with a high disease activity who need to be visited and treated more regularly. (2) Methods: We analyzed levels of aab against Angiotensin II receptor type 1 (AT1-receptor), Protease-activated receptors (PAR1), vascular endothelial growth factor (VEGF) -A, VEGF-B, and VEGF-receptor 2 in sera of 164 nAMD patients. In a follow-up period of five years, we evaluated changes in functional and morphological characteristics. Using correlation analyses, multiple regression models, and receiver operator characteristics, we assessed whether the five aab have a clinical significance as biomarkers that correspond to the clinical properties. (3) Results: Neither the analyzed aab individually nor taken together as a network showed statistically significant results that would allow us to draw conclusions on the clinical five-year course in nAMD patients. (4) Conclusions: The five aab that we analyzed do not correspond to the clinical five-year course of nAMD patients. However, larger, prospective studies should reevaluate different and more aab to gain deeper insights. [ABSTRACT FROM AUTHOR]

Numerical experiments of seismic wave propagation in a laterally homogeneous layered medium explore subsurface imaging at subwavelength distances for dense seismic arrays. We choose a time-reversal approach to simulate fundamental mode Rayleigh surface wavefields that are equivalent to the cross-correlation results of three-component ambient seismic field records. We demonstrate that the synthesized 2-D spatial autocorrelation fields in the time domain support local or so-called focal spot imaging. Systematic tests involving clean isotropic surface wavefields but also interfering body wave components and anisotropic incidence assess the accuracy of the phase velocity and dispersion estimates obtained from focal spot properties. The results suggest that data collected within half a wavelength around the origin is usually sufficient to constrain the used Bessel functions models. Generally, the cleaner the surface wavefield the smaller the fitting distances that can be used to accurately estimate the local Rayleigh wave speed. Using models based on isotropic surface wave propagation we find that phase velocity estimates from vertical–radial component data are less biased by P -wave energy compared to estimates obtained from vertical–vertical component data, that even strong anisotropic surface wave incidence yields phase velocity estimates with an accuracy of 1 per cent or better, and that dispersion can be studied in the presence of noise. Estimates using a model to resolve potential medium anisotropy are significantly biased by anisotropic surface wave incidence. The overall accurate results obtained from near-field measurements using isotropic medium assumptions imply that dense array seismic Rayleigh wave focal spot imaging can increase the depth sensitivity compared to ambient noise surface wave tomography. The analogy to elastography focal spot medical imaging implies that a high station density and clean surface wavefields support subwavelength resolution of lateral medium variations. [ABSTRACT FROM AUTHOR]

Objectives. A multiagency intervention was implemented in Yakima County, Wash, to reduce the incidence of Salmonella serotype Typhimurium infections resulting from eating queso fresco (fresh cheese) made from raw milk, a traditional food in the Hispanic diet. Methods. A pasteurized-milk queso fresco recipe with taste and texture acceptable to the Hispanic community was developed. Trained Hispanic volunteers conducted safe cheese workshops, which were attended by more than 225 persons. Results. Workshop participants' acceptance of the new recipe was excellent and positive behavior changes were maintained over 6 months. Conclusions. Educational interventions in Hispanic communities can reduce the incidence of Salmonella Typhimurium associated with eating queso fresco. (Am J Public Health. 1999 ;89:1421-1424) [ABSTRACT FROM AUTHOR]

Proposes models for the role of mismatch pair functions in the generation of meiotic conversion gradients of Saccharomyces cerevisiae. Limitation of hybrid DNA flanking by the recognition of mismatches by mismatch repair enzymes; Restoration of Mendelian segregation with increasing distance from double strand break sites.