Observations of large parallel electric fields in the auroral ionosphere

NASA Technical Reports Server (NTRS)

Mozer, F. S.

1976-01-01

Rocket borne measurements employing a double probe technique were used to gather evidence for the existence of electric fields in the auroral ionosphere having components parallel to the magnetic field direction. An analysis of possible experimental errors leads to the conclusion that no known uncertainties can account for the roughly 10 mV/m parallel electric fields that are observed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Japikse, C.

In January 1994, EPA signed an agreement with three private companies--Monsanto, DuPont, and General Electric (GE)--to develop a new remediation technology. Dubbed the ``lasagna`` process because of its layers, this technology cleans up liquid-borne organic and inorganic contaminants in dense, clay-like soils. Initial work is focused on removing chlorinated solvents. The lasagna process allows the soil to be remediated in situ by using low-voltage electric current to move contaminated ground water through treatment zones in the soil. Depending on the characteristics of the individual site, the process can be done in either a horizontal or vertical configuration. Lasagna partnership membersmore » are pursuing a range of options for developing the process for commercial use. Monsanto conducts research on the use of electric currents to move contaminants through soil. DuPont contributes expertise on the installation of vertical treatment zones and electrodes. GE performs computer-driven modeling of how contaminants move through soil.« less

A local network integrated into a balloon-borne apparatus

NASA Astrophysics Data System (ADS)

Imori, Masatosi; Ueda, Ikuo; Shimamura, Kotaro; Maeno, Tadashi; Murata, Takahiro; Sasaki, Makoto; Matsunaga, Hiroyuki; Matsumoto, Hiroshi; Shikaze, Yoshiaki; Anraku, Kazuaki; Matsui, Nagataka; Yamagami, Takamasa

A local network is incorporated into an apparatus for a balloon-borne experiment. A balloon-borne system implemented in the apparatus is composed of subsystems interconnected through a local network, which introduces modular architecture into the system. The network decomposes the balloon-borne system into subsystems, which are similarly structured from the point of view that the systems is kept under the control of a ground station. The subsystem is functionally self-contained and electrically independent. A computer is integrated into a subsystem, keeping the subsystem under the control. An independent group of batteries, being dedicated to a subsystem, supplies the whole electricity of the subsystem. The subsystem could be turned on and off independently of the other subsystems. So communication among the subsystems needs to be based on such a protocol that could guarantee the independence of the individual subsystems. An Omninet protocol is employed to network the subsystems. A ground station sends commands to the balloon-borne system. The command is received and executed at the system, then results of the execution are returned to the ground station. Various commands are available so that the system borne on a balloon could be controlled and monitored remotely from the ground station. A subsystem responds to a specific group of commands. A command is received by a transceiver subsystem and then transferred through the network to the subsystem to which the command is addressed. Then the subsystem executes the command and returns results to the transceiver subsystem, where the results are telemetered to the ground station. The network enhances independence of the individual subsystems, which enables programs of the individual subsystems to be coded independently. Independence facilitates development and debugging of programs, improving the quality of the system borne on a balloon.

Physics models of centriole replication.

PubMed

Cheng, Kang; Zou, Changhua

2006-01-01

Our previous pre-clinic experimental results have showed that the epithelialization can be enhanced by the externally applied rectangular pulsed electrical current stimulation (RPECS). The results are clinically significant for patients, especially for those difficult patients whose skin wounds need long periods to heal. However, the results also raise questions: How does the RPECS accelerate the epithelium cell proliferation? To answer these questions, we have previously developed several models for animal cells, in a view of physics, to explain mechanisms of mitosis and cytokinesis at a cellular level, and separation of nucleotide sequences and the unwinding of a double helix during DNA replication at a bio-molecular level. In this paper, we further model the mechanism of centriole replication during a natural and normal mitosis and cytokinesis to explore the mechanism of epithelialization enhanced with the externally applied RPECS at a bio-molecular level. Our models suggest: (1) Centriole replication is an information flowing. The direction of the information flowing is from centrioles to centrioles based on a cylindrical template of 9 x 3 protein microtubules (MTs) pattern. (2) A spontaneous and strong electromagnetic field (EMF) force is a pushing force that separates a mother and a daughter centrioles in centrosomes or in cells, while a pulling force of interacting fibers and pericentriolar materials delivers new babies. The newly born babies inherit the pattern information from their mother(s) and grow using microtubule fragments that come through the centrosome pores. A daughter centriole is always born and grows along stronger EMF. The EMF mostly determines centrioles positions and plays key role in centriole replication. We also hypothesize that the normal centriole replication could not been disturbed in centrosome in the epithelium cells by our RPECS, because the centrioles have two non-conducting envelope (cell and centrosome membranes), that protect the normal duplication. The induced electric field by externally applied RPECS could be mild compared with the spontaneous and natural electric field of the centrioles. Therefore, the centriole replication during the epithelium cellular proliferation may be directly, as well as indirectly (e.g., somatic reflex) accelerated by the RPECS.

Relation Between Lightning Activity of Summer and Winter Thunderclouds and Surface Electric Field Variation, Japan

NASA Technical Reports Server (NTRS)

Michimoto, K.; Shimura, T.; Suzuki, T.

1999-01-01

In winter, active convective clouds frequently form along the coastline of the Hokuriku district, in association with strong advection of Siberian air masses over the Sea of Japan. On the other hand, in summer, many thunderclouds form in the Kanto region in the afternoon every day. Summer and winter thunderclouds were investigated by field works, operation of the C- and X-band weather radars and a car-borne fieldmill. The investigation found a very close relation between the temporal variation of 3-dimensional radar echo and surface electric field magnitude detected by a car-borne fieldmill in the case of summer thunderclouds and winter convective clouds or thunderclouds. The study probed the close relation among radar echoes, quantity of thunderclouds and surface electric field magnitude in the summer and winter seasons. We think that summer thundercloud activity can basically be equated with winter thundercloud lightning activity, except that the magnitude of surface electric field under summer thunderclouds in the case of the Kanto region cannot be equated with that under winter thunderclouds in the case of the Hokuriku district in winter.

Global electrodynamics from superpressure balloons

NASA Technical Reports Server (NTRS)

Holzworth, R. H.; Hu, H.

1995-01-01

Electric field and conductivity measurements in the stratosphere between November 1992 and March 1993 have been made using superpressure balloons in the southern hemisphere. Over 400 payload-days of data have been made during a record setting experiment called ELBBO (Extended Life Balloon Borne Observatories). This experiment resulted in 4 flights aloft simultaneously for over 2 months including one flight which lasted over 4 months. Electrodynamical coupling between the atmosphere and ionosphere is studied using the measured electric fields, and a simple empirical model of the stratospheric conductivity. Altitude profiles of conductivity have been obtained from several superpressure balloon flights using the large end-of-flight altitude swings on the last few days of each flight (as the balloon begins to loose superpressure). Coupling between the fields and atmospheric inertial waves has been observed. Effects and dynamics of the global circuit suggest that standard models are missing significant phenomena. Large scale ionospheric convection activity has been studied from the polar cap to the middle latitudes. Cusp latitude fields have been continuously measured for many days in a row.

Ab initio design of laser pulses to control molecular motion

NASA Astrophysics Data System (ADS)

Balint-Kurti, Gabriel; Ren, Qinghua; Manby, Frederick; Artamonov, Maxim; Ho, Tak-San; Rabitz, Herschel; Zou, Shiyang; Singh, Harjinder

2007-03-01

Our recent attempts to design laser pulses entirely theoretically, in a quantitative and accurate manner, so as to fully understand the underlying mechanisms active in the control process will be outlined. We have developed a new Born-Oppenheimer like separation called the electric-nuclear Born-Oppenheimer (ENBO) approximation. In this approximation variations of both the nuclear geometry and of the external electric field are assumed to be slow compared with the speed at which the electronic degrees of freedom respond to these changes. This assumption permits the generation of a potential energy surface that depends not only on the relative geometry of the nuclei, but also on the electric field strength and on the orientation of the molecule with respect to the electric field. The range of validity of the ENBO approximation is discussed. Optimal control theory is used along with the ENBO approximation to design laser pulses for exciting vibrational and rotational motion in H2 and CO molecules. Progress on other applications, including controlling photodissociation processes, isotope separation, stabilization of molecular Bose-Einstein condensates as well as applications to biological molecules also be presented. *Support acknowledged from EPSRC.

CRIT II electric, magnetic, and density measurements within an ionizing neutral stream

NASA Technical Reports Server (NTRS)

Swenson, C. M.; Kelley, M. C.; Primdahl, F.; Baker, K. D.

1990-01-01

Measurements from rocket-borne sensors inside a high-velocity neutral barium beam show a-factor-of-six increase in plasma density in a moving ionizing front. This region was colocated with intense fluctuating electric fields at frequencies well under the lower hybrid frequency for a barium plasma. Large quasi-dc electric and magnetic field fluctuations were also detected with a large component of the current and the electric field parallel to B(0). An Alfven wave with a finite electric field component parallel to the geomagnetic field was observed to propagate along B(0), where it was detected by an instrumented subpayload.

Long Fuse, Big Bang: Thomas Edison, Electricity, and the Locus of Innovation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hargadon, Andrew

2012-10-22

Calls for breakthroughs in science and technology have never been louder, and yet the demand for innovation is made more challenging by public and political misconceptions surrounding where, when, and how it happens. Professor Andrew Hargadon uses historical research to advance our current understanding of the innovation process. He discussed the social and technical context in which electric light, and the modern electric power infrastructure, were born and considers its implications for managing innovation in science and technology today.

Investigating the Effect of Charge Hydration Asymmetry and Incorporating it in Continuum Solvation Framework

NASA Astrophysics Data System (ADS)

Mukhopadhyay, Abhishek

One of the essential requirements of biomolecular modeling is an accurate description of water as a solvent. The challenge is to make this description computationally facile - reasonably fast, simple, robust and easy to incorporate into existing software packages, yet accurate. The most rigorous procedure to model the effect of aqueous solvent is to explicitly model every water molecule in the system. For many practical applications, this approach is computationally too intense, as the number of required water atoms is on an average at least one order of magnitude larger than the number of atoms of the molecule of interest. Implicit solvent models, in which solvent molecules are replaced by a continuous dielectric, have become a popular alternative to explicit solvent methods. However, implicit solvation models often lack various microscopic details which are crucial for accuracy. One such missing effect that is currently missing from popular implicit models is the so called effect of charge hydration asymmetry (CHA). The missing effect of charge hydration asymmetry - the asymmetric response of water upon the sign of solute charge - manifests a characteristic, strong dependence of solvation free energies on the sign of solute charge. Here, we incorporate this missing effect into the continuum solvation framework via the conceptually simplest Born equation and also in the generalized Born model. We identify the key electric multipole moments of model water molecules critical for the various degrees of CHA effect observed in studies based on molecular dynamics simulations using different rigid water models. We then use this gained insight to incorporate this effect first into the Born model and then into the generalized Born model. The proposed framework significantly improves accuracy of the hydration free energy estimates tested on a comprehensive set of varied molecular solutes - monovalent and divalent ions, small drug-like molecules, charged and uncharged amino acid dipeptides, and small proteins. We finally develop a methodology to resolve the issue with unacceptably large uncertainty that stems from a variety of fundamental and technical difficulties in experimental quantification of CHA from charged solutes. Using the proposed corrections in the continuum framework, we untangle the charge-asymmetric response of water from its symmetric response, and further circumvent the difficulties by extracting accurate estimate propensity of water to cause CHA from accurate experimental hydration free energies of neutral polar molecules. We show that the asymmetry in water's response is strong, about 50% of the symmetric response.

Characterisation of structure-borne sound source using reception plate method.

PubMed

Putra, A; Saari, N F; Bakri, H; Ramlan, R; Dan, R M

2013-01-01

A laboratory-based experiment procedure of reception plate method for structure-borne sound source characterisation is reported in this paper. The method uses the assumption that the input power from the source installed on the plate is equal to the power dissipated by the plate. In this experiment, rectangular plates having high and low mobility relative to that of the source were used as the reception plates and a small electric fan motor was acting as the structure-borne source. The data representing the source characteristics, namely, the free velocity and the source mobility, were obtained and compared with those from direct measurement. Assumptions and constraints employing this method are discussed.

Outside the Hull Electric Propulsion for a Submarine

DTIC Science & Technology

1990-05-01

improvements. Outside The Hull Electric Propulsion ’OTHEP) uses an inverted geometry, squirrel-cage induction motor to drive a large hub-to-diameter ratio...which is used for shipboard air- borne noise prediction, is adapted to describe the noise which is radiated into the sea. With the estimated...123 5 4.2.3 Using the Forces as Input to Acoustic Analysis S. .. . . . . . .... . . . . . . . . . . . . .. . . . ... . . . . . . . 1 2

Viral contacts confound studies of childhood leukemia and high-voltage transmission lines.

PubMed

Sahl, J D

1994-05-01

Studies of childhood leukemia have reported a link with residential proximity to electric utility facilities. This paper elaborates on the hypothesis that residential proximity to electric utility transmission-systems is a surrogate for viral contacts, a potential confounder in these studies. While the causal implications of increased viral contacts is not established, the assumption made here is that a significant component of childhood leukemia has an infectious etiology. Increased viral contacts can result from residential mobility, being first born, or use of community childcare facilities. Re-analysis of existing studies should look specifically for the interaction between childhood leukemia, markers for viral contacts (e.g., residential mobility, birth order, use of outside childcare facilities), and residential proximity to high-voltage transmission lines. New study designs should include parameters to test directly for a virus-related infectious model for childhood leukemia.

A network-patch methodology for adapting agent-based models for directly transmitted disease to mosquito-borne disease.

PubMed

Manore, Carrie A; Hickmann, Kyle S; Hyman, James M; Foppa, Ivo M; Davis, Justin K; Wesson, Dawn M; Mores, Christopher N

2015-01-01

Mosquito-borne diseases cause significant public health burden and are widely re-emerging or emerging. Understanding, predicting, and mitigating the spread of mosquito-borne disease in diverse populations and geographies are ongoing modelling challenges. We propose a hybrid network-patch model for the spread of mosquito-borne pathogens that accounts for individual movement through mosquito habitats, extending the capabilities of existing agent-based models (ABMs) to include vector-borne diseases. The ABM are coupled with differential equations representing 'clouds' of mosquitoes in patches accounting for mosquito ecology. We adapted an ABM for humans using this method and investigated the importance of heterogeneity in pathogen spread, motivating the utility of models of individual behaviour. We observed that the final epidemic size is greater in patch models with a high risk patch frequently visited than in a homogeneous model. Our hybrid model quantifies the importance of the heterogeneity in the spread of mosquito-borne pathogens, guiding mitigation strategies.

Using affordable LED arrays for photo-stimulation of neurons.

PubMed

Valley, Matthew; Wagner, Sebastian; Gallarda, Benjamin W; Lledo, Pierre-Marie

2011-11-15

Standard slice electrophysiology has allowed researchers to probe individual components of neural circuitry by recording electrical responses of single cells in response to electrical or pharmacological manipulations(1,2). With the invention of methods to optically control genetically targeted neurons (optogenetics), researchers now have an unprecedented level of control over specific groups of neurons in the standard slice preparation. In particular, photosensitive channel rhodopsin-2 (ChR2) allows researchers to activate neurons with light(3,4). By combining careful calibration of LED-based photostimulation of ChR2 with standard slice electrophysiology, we are able to probe with greater detail the role of adult-born interneurons in the olfactory bulb, the first central relay of the olfactory system. Using viral expression of ChR2-YFP specifically in adult-born neurons, we can selectively control young adult-born neurons in a milieu of older and mature neurons. Our optical control uses a simple and inexpensive LED system, and we show how this system can be calibrated to understand how much light is needed to evoke spiking activity in single neurons. Hence, brief flashes of blue light can remotely control the firing pattern of ChR2-transduced newborn cells.

Fundamental Limits on the Imaging and Polarisation Properties of Far-Infrared Detectors

NASA Technical Reports Server (NTRS)

Thomas, Christopher N.; Withington, Stafford; Chuss, David T.; Wollack, Edward J.; Moseley, S. Harvey

2009-01-01

Far-infrared bolometric detectors are used extensively in ground-based and space-borne astronomy, and thus it is important to understand their optical behaviour precisely. We have studied the intensity and polarisation response of free-space bolometers, and shown that when the size of the absorber is reduced below a wavelength, the response changes from being that of a classical optical detector to that of a few-mode antenna. We have calculated the modal content of the reception patterns, and found that for any volumetric detector having a side length of less than a wavelength, three magnetic and three electric dipoles characterize the behaviour. The size of the absorber merely determines the relative strengths of the contributions. The same formalism can be applied to thin-film absorbers, where the induced current is forced to flow in a plane. In this case, one magnetic and two electric dipoles characterize the behaviour. The ability to model easily the intensity, polarisation, and straylight characteristics of electrically-small detectors will be of great value when designing high-performance polarimetric imaging arrays.

Developing Islamic Financial Products for Financing Solar Energy with a Special Reference to Qatar and Algeria

NASA Astrophysics Data System (ADS)

Tabet, Imene Nouar

Renewable energy has become an important part of the international energy mix. This thesis aims at developing Islamic financial schemes for financing photovoltaic solar energy roof-tops and solar farms. Being an evolving technology based sector with high capital expenditures imposed a challenge for this alternative source of energy to grow especially in countries where electricity costs are low and prices are heavily subsidised. The first two chapters provide a comprehensive overview of solar energy industry with the various policies and financing models that were developed and adopted in various countries. It is found that most of its growth was dependent on government support even in financing. Ijarah Sukuk were developed for financing roof-tops in Qatar, such that the house owners do not have to pay any amount and would get the solar panels at maturity where they would be entitled to their benefit. The cost would be borne by the investors who receive stable rental payments along with their capital throughout the financing period, while electric company would be provided with the electricity at a rate lower than its production cost, hence offering it subsidy savings; the lessee who lives in house would be provided with incentives in the form of electricity-pay break. Although the electricity sector in the country remains highly dependent on government support, the model, in its hypothetical example, provides investors with 8% Internal Rate of Return. On the other hand, Output-sharing Sukuk model is developed for financing solar farms in the context of Algeria, based on the known Islamic financial contract of Muzara'ah. The state-owned electric company contributes the land, the Sukuk holders own the panels, and the developer provides management of the farm. A hypothetical example is also given with calculation of cash flow and investors' Internal Rate of Return which comes to be 7.1029% per annum.

Simultaneous measurements of auroral particles and electric currents by a rocket-borne instrument system - Introductory remarks

NASA Technical Reports Server (NTRS)

Anderson, H. R.; Cloutier, P. A.

1975-01-01

A rocket-borne experiment package has been designed to obtain simultaneous in situ measurements of the pitch angle distributions and energy spectra of primary auroral particles, the flux of neutral hydrogen at auroral energies, the electric currents flowing in the vicinity of the auroral arc as determined from vector magnetic data, and the modulation of precipitating electrons in the frequency range 0.5-10 MHz. The experiment package was launched by a Nike-Tomahawk rocket from Poker Flat, Alaska, at 0722 UT on Feb. 25, 1972, over a bright auroral band. This paper is intended to serve as an introduction to the detailed discussion of results given in the companion papers. As such it includes a brief review of the general problem, a discussion of the rocket instrumentation, a delineation of the auroral and geomagnetic conditions at the time of launch, and comments on the overall payload performance.

Long term changes in electrical conductivity in stratosphere over Hyderabad (India), balloon borne results

NASA Astrophysics Data System (ADS)

Gupta, Surya

2012-07-01

The stratospheric conductivity plays important role in coupling processes between lower atmosphere and ionosphere. It is an important parameter of global electric circuit. The conductivity in troposphere and in stratosphere is mainly due to ionization produced by cosmic rays. The conductivity in stratosphere is measured mainly by balloon borne technique. In country-regionIndia, we had a national program IMAP (1982-1994) to measure conductivity and electric field in stratosphere from CityHyderabad (country-regionplaceIndia). Five institutes took part in this program. Namely NPL (CityNew Delhi), PRL (Ahmedabad), CESS (CityTrivandrum), IIG (Mumbai) and TIFR Balloon facility (CityplaceHyderabad). The vertical profiles on Ion Conductivity (both positive and negative) were measured from CityplaceHyderabad using different techniques. The measurements were done during different solar activity period. Measurements were done at float altitude also. It was observed that conductivity values in stratosphere is larger in high solar activity period compared to low solar activity period by 30%. This was a new finding and will be discussed in terms of composition change due to change in U.V. (200-300 nm) radiation intensity with solar activity. Over mid and polar latitude American scientists have conducted such measurements by balloon borne techniques (covering a period of about twenty-five years (1975-2000). Temporal variations of similar nature were also observed at mid-latitudes, while no correlation was seen at polar latitudes. The conductivity results of CityplaceHyderabad were compared with measurements carried out at different latitudes and different longitudes by other workers and will be discussed in this presentation.

Estimating patient-borne water and electricity costs in home hemodialysis: a simulation

PubMed Central

Nickel, Matthew; Rideout, Wes; Shah, Nikhil; Reintjes, Frances; Chen, Justin Z.; Burrell, Robert; Pauly, Robert P.

2017-01-01

Background: Home hemodialysis is associated with lower costs to the health care system compared with conventional facility-based hemodialysis because of lower staffing and overhead costs, and by transferring the treatment cost of utilities (water and power) to the patient. The purpose of this study was to determine the utility costs of home hemodialysis and create a formula such that patients and renal programs can estimate the annual patient-borne costs involved with this type of treatment. Methods: Seven common combinations of treatment duration and dialysate flows were replicated 5 times using various combinations of home hemodialysis and reverse osmosis machines. Real-time utility (electricity and water) consumption was monitored during these simulations. A generic formula was developed to allow patients and programs to calculate a more precise estimate of utility costs based on individual combinations of dialysis intensity, frequency and utility costs unique to any patient. Results: Using typical 2014 utility costs for Edmonton, the most expensive prescription was for nocturnal home hemodialysis (8 h at 300 mL/min, 6 d/wk), which resulted in a utility cost of $1269 per year; the least expensive prescription was for conventional home hemodialysis (4 h at 500 mL/min, 3 d/wk), which cost $420 per year. Water consumption makes up most of this expense, with electricity accounting for only 12% of the cost. Interpretation: We show that a substantial cost burden is transferred to the patient on home hemodialysis, which would otherwise be borne by the renal program. PMID:28401120

A Stochastic Tick-Borne Disease Model: Exploring the Probability of Pathogen Persistence.

PubMed

Maliyoni, Milliward; Chirove, Faraimunashe; Gaff, Holly D; Govinder, Keshlan S

2017-09-01

We formulate and analyse a stochastic epidemic model for the transmission dynamics of a tick-borne disease in a single population using a continuous-time Markov chain approach. The stochastic model is based on an existing deterministic metapopulation tick-borne disease model. We compare the disease dynamics of the deterministic and stochastic models in order to determine the effect of randomness in tick-borne disease dynamics. The probability of disease extinction and that of a major outbreak are computed and approximated using the multitype Galton-Watson branching process and numerical simulations, respectively. Analytical and numerical results show some significant differences in model predictions between the stochastic and deterministic models. In particular, we find that a disease outbreak is more likely if the disease is introduced by infected deer as opposed to infected ticks. These insights demonstrate the importance of host movement in the expansion of tick-borne diseases into new geographic areas.

Projecting Individualized Absolute Invasive Breast Cancer Risk in US Hispanic Women

PubMed Central

John, Esther M.; Slattery, Martha L.; Gomez, Scarlett Lin; Yu, Mandi; LaCroix, Andrea Z.; Pee, David; Chlebowski, Rowan T.; Hines, Lisa M.; Thompson, Cynthia A.; Gail, Mitchell H.

2017-01-01

Background: There is no model to estimate absolute invasive breast cancer risk for Hispanic women. Methods: The San Francisco Bay Area Breast Cancer Study (SFBCS) provided data on Hispanic breast cancer case patients (533 US-born, 553 foreign-born) and control participants (464 US-born, 947 foreign-born). These data yielded estimates of relative risk (RR) and attributable risk (AR) separately for US-born and foreign-born women. Nativity-specific absolute risks were estimated by combining RR and AR information with nativity-specific invasive breast cancer incidence and competing mortality rates from the California Cancer Registry and Surveillance, Epidemiology, and End Results program to develop the Hispanic risk model (HRM). In independent data, we assessed model calibration through observed/expected (O/E) ratios, and we estimated discriminatory accuracy with the area under the receiver operating characteristic curve (AUC) statistic. Results: The US-born HRM included age at first full-term pregnancy, biopsy for benign breast disease, and family history of breast cancer; the foreign-born HRM also included age at menarche. The HRM estimated lower risks than the National Cancer Institute’s Breast Cancer Risk Assessment Tool (BCRAT) for US-born Hispanic women, but higher risks in foreign-born women. In independent data from the Women’s Health Initiative, the HRM was well calibrated for US-born women (observed/expected [O/E] ratio = 1.07, 95% confidence interval [CI] = 0.81 to 1.40), but seemed to overestimate risk in foreign-born women (O/E ratio = 0.66, 95% CI = 0.41 to 1.07). The AUC was 0.564 (95% CI = 0.485 to 0.644) for US-born and 0.625 (95% CI = 0.487 to 0.764) for foreign-born women. Conclusions: The HRM is the first absolute risk model that is based entirely on data specific to Hispanic women by nativity. Further studies in Hispanic women are warranted to evaluate its validity. PMID:28003316

Determination of deuteron quadrupole moment from calculations of the electric field gradient in D{sub 2} and HD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pavanello, Michele; Tung Weicheng; Adamowicz, Ludwik

2010-04-15

We have carried out an accurate determination of the quadrupole moment of the deuteron nucleus. The evaluation of the constant is achieved by combining high accuracy Born-Oppenheimer calculations of the electric field gradient at the nucleus in the H{sub 2} molecule with spectroscopic measurements of the quadrupolar splitting in D{sub 2} and HD. The derived value is Q=0.285783(30) fm{sup 2}.

Non-linear 3-D Born shear waveform tomography in Southeast Asia

NASA Astrophysics Data System (ADS)

Panning, Mark P.; Cao, Aimin; Kim, Ahyi; Romanowicz, Barbara A.

2012-07-01

Southeast (SE) Asia is a tectonically complex region surrounded by many active source regions, thus an ideal test bed for developments in seismic tomography. Much recent development in tomography has been based on 3-D sensitivity kernels based on the first-order Born approximation, but there are potential problems with this approach when applied to waveform data. In this study, we develop a radially anisotropic model of SE Asia using long-period multimode waveforms. We use a theoretical 'cascade' approach, starting with a large-scale Eurasian model developed using 2-D Non-linear Asymptotic Coupling Theory (NACT) sensitivity kernels, and then using a modified Born approximation (nBorn), shown to be more accurate at modelling waveforms, to invert a subset of the data for structure in a subregion (longitude 75°-150° and latitude 0°-45°). In this subregion, the model is parametrized at a spherical spline level 6 (˜200 km). The data set is also inverted using NACT and purely linear 3-D Born kernels. All three final models fit the data well, with just under 80 per cent variance reduction as calculated using the corresponding theory, but the nBorn model shows more detailed structure than the NACT model throughout and has much better resolution at depths greater than 250 km. Based on variance analysis, the purely linear Born kernels do not provide as good a fit to the data due to deviations from linearity for the waveform data set used in this modelling. The nBorn isotropic model shows a stronger fast velocity anomaly beneath the Tibetan Plateau in the depth range of 150-250 km, which disappears at greater depth, consistent with other studies. It also indicates moderate thinning of the high-velocity plate in the middle of Tibet, consistent with a model where Tibet is underplated by Indian lithosphere from the south and Eurasian lithosphere from the north, in contrast to a model with continuous underplating by Indian lithosphere across the entire plateau. The nBorn anisotropic model detects negative ξ anomalies suggestive of vertical deformation associated with subducted slabs and convergent zones at the Himalayan front and Tien Shan at depths near 150 km.

Stability under scalar perturbations and quasinormal modes of 4D Einstein-Born-Infeld dilaton spacetime: exact spectrum

NASA Astrophysics Data System (ADS)

Destounis, Kyriakos; Panotopoulos, Grigoris; Rincón, Ángel

2018-02-01

We study the stability under scalar perturbations, and we compute the quasinormal modes of the Einstein-Born-Infeld dilaton spacetime in 1+3 dimensions. Solving the full radial equation in terms of hypergeometric functions, we provide an exact analytical expression for the spectrum. We find that the frequencies are purely imaginary, and we confirm our results by computing them numerically. Although the scalar field that perturbs the black hole is electrically neutral, an instability similar to that seen in charged scalar perturbations of the Reissner-Nordström black hole is observed.

[The clinical and cytogenetic characteristics of the children born to persons with a history of 1st- and 2d-degree acute radiation sickness as a result of the accident at the Chernobyl Atomic Electric Power Station].

PubMed

Stepanova, E I; Vaniurikhina, E A

1993-01-01

We have examined 15 children (born in 1987-1988), whose fathers liquidated the aftereffects of the accident at Chernobyl Nuclear Power Plant and suffered from acute radiation sickness of the 1st and 2nd stages and 50 children of the control group. The obtained data showed that the number of small developmental abnormalities (stigmas of dysembryogenesis) increased as well as the chromatid aberration frequency as compared with the control group.

Ab initio molecular dynamics in a finite homogeneous electric field.

PubMed

Umari, P; Pasquarello, Alfredo

2002-10-07

We treat homogeneous electric fields within density functional calculations with periodic boundary conditions. A nonlocal energy functional depending on the applied field is used within an ab initio molecular dynamics scheme. The reliability of the method is demonstrated in the case of bulk MgO for the Born effective charges, and the high- and low-frequency dielectric constants. We evaluate the static dielectric constant by performing a damped molecular dynamics in an electric field and avoiding the calculation of the dynamical matrix. Application of this method to vitreous silica shows good agreement with experiment and illustrates its potential for systems of large size.

What the R & D Man Needs in Scientific Furniture and Why.

ERIC Educational Resources Information Center

Hallenberg, E.X.

1964-01-01

The complexity of today's research laboratories requires a completely controllable environmental surrounding. Research facilities require carefully controlled temperatures, relative humidity, and moisture, and must be free of interference from air-borne sound, mechanical vibrations, and electrical sources. Also desirable are special power…

Projecting Individualized Absolute Invasive Breast Cancer Risk in US Hispanic Women.

PubMed

Banegas, Matthew P; John, Esther M; Slattery, Martha L; Gomez, Scarlett Lin; Yu, Mandi; LaCroix, Andrea Z; Pee, David; Chlebowski, Rowan T; Hines, Lisa M; Thompson, Cynthia A; Gail, Mitchell H

2017-02-01

There is no model to estimate absolute invasive breast cancer risk for Hispanic women. The San Francisco Bay Area Breast Cancer Study (SFBCS) provided data on Hispanic breast cancer case patients (533 US-born, 553 foreign-born) and control participants (464 US-born, 947 foreign-born). These data yielded estimates of relative risk (RR) and attributable risk (AR) separately for US-born and foreign-born women. Nativity-specific absolute risks were estimated by combining RR and AR information with nativity-specific invasive breast cancer incidence and competing mortality rates from the California Cancer Registry and Surveillance, Epidemiology, and End Results program to develop the Hispanic risk model (HRM). In independent data, we assessed model calibration through observed/expected (O/E) ratios, and we estimated discriminatory accuracy with the area under the receiver operating characteristic curve (AUC) statistic. The US-born HRM included age at first full-term pregnancy, biopsy for benign breast disease, and family history of breast cancer; the foreign-born HRM also included age at menarche. The HRM estimated lower risks than the National Cancer Institute's Breast Cancer Risk Assessment Tool (BCRAT) for US-born Hispanic women, but higher risks in foreign-born women. In independent data from the Women's Health Initiative, the HRM was well calibrated for US-born women (observed/expected [O/E] ratio = 1.07, 95% confidence interval [CI] = 0.81 to 1.40), but seemed to overestimate risk in foreign-born women (O/E ratio = 0.66, 95% CI = 0.41 to 1.07). The AUC was 0.564 (95% CI = 0.485 to 0.644) for US-born and 0.625 (95% CI = 0.487 to 0.764) for foreign-born women. The HRM is the first absolute risk model that is based entirely on data specific to Hispanic women by nativity. Further studies in Hispanic women are warranted to evaluate its validity. Published by Oxford University Press 2016. This work is written by US Government employees and is in the public domain in the US.

Optical Remote Sensing of Electric Fields Above Thunderstorms

NASA Astrophysics Data System (ADS)

Burns, B. M.; Carlson, B. E.; Lauben, D.; Cohen, M.; Smith, D.; Inan, U. S.

2010-12-01

Measurement of thunderstorm electric fields typically require balloon-borne measurements in the region of interest. Such measurements are cumbersome and provide limited information at a single point. Remote sensing of electric fields by Kerr-effect induced optical polarization changes of background skylight circumvents many of these difficulties and can in principle provide a high-speed movie of electric field behavior. Above-thundercloud 100 kV/m quasi-static electric fields are predicted to produce polarization changes at above the part in one million level that should be detectable at a ground instrument featuring 1 cm2sr geometric factor and 1 kHz bandwidth (though more sensitivity is nonetheless desired). Currently available optical and electronic components may meet these requirements. We review the principles of this measurement and discuss the current status of a field-ready prototype instrument currently in construction.

Born-Infeld Gravity Revisited

NASA Astrophysics Data System (ADS)

Setare, M. R.; Sahraee, M.

2013-12-01

In this paper, we investigate the behavior of linearized gravitational excitation in the Born-Infeld gravity in AdS3 space. We obtain the linearized equation of motion and show that this higher-order gravity propagate two gravitons, massless and massive, on the AdS3 background. In contrast to the R2 models, such as TMG or NMG, Born-Infeld gravity does not have a critical point for any regular choice of parameters. So the logarithmic solution is not a solution of this model, due to this one cannot find a logarithmic conformal field theory as a dual model for Born-Infeld gravity.

NASA upper atmosphere research program: Research summaries, 1990 - 1991. Report to the Congress and the Environmental Protection Agency

NASA Technical Reports Server (NTRS)

1992-01-01

The objectives, status, and accomplishments of the research tasks supported under the NASA Upper Atmosphere Research Program (UARP) are presented. The topics covered include the following: balloon-borne in situ measurements; balloon-borne remote measurements; ground-based measurements; aircraft-borne measurements; rocket-borne measurements; instrument development; reaction kinetics and photochemistry; spectroscopy; stratospheric dynamics and related analysis; stratospheric chemistry, analysis, and related modeling; and global chemical modeling.

[Study on a new prevention and control model on soil-borne parasitic diseases in rural areas of China].

PubMed

Li, Xue-Ming; Chen, Ying-Dan; Xu, Long-Qi; Zhou, Chang-Hai; Ou-Yang, Yi; Lin, Rui; Yang, Fang-Fang; Zhang, Xiao-Juan; Wang, Ge; Liu, Teng; Wang, Jing

2011-12-01

To explore a new prevention and control model on soil-borne parasitic diseases in rural areas of China. Eight provinces and autonomous regions were selected in China as demonstration areas implementing integrated control on soil-borne parasitic diseases. The integrated control measures included authority organization and harmonization, health education, deworming, and environment modification. After three years, the infection rates of soil-borne parasitic diseases were significantly decreased in these areas. There were three safe guard and organization modes, three health education modes, four mass worming medication modes, and two modes of water, toilet and environment changes. The work in the various demonstration areas was summarized which pointed out a new model with efficiency and local characteristics on soil-borne parasitic disease prevention and control.

A finite element study on the effects of midsymphyseal distraction osteogenesis on the mandible and articular disc.

PubMed

Kim, Ki-Nam; Cha, Bong-Kuen; Choi, Dong-Soon; Jang, Insan; Yi, Yang-Jin; Jost-Brinkmann, Paul-Georg

2012-05-01

To evaluate the biomechanical effect of midsymphyseal distraction osteogenesis with three types of distractors on the mandible and articular disc using a three-dimensional finite element model analysis. A virtual model of the mandible was produced from computed tomography scan images of a healthy 27-year-old man. On the finite element model of the mandible, expansion of the bone-borne, tooth-borne, and hybrid type distractors were simulated with the jaw-closing muscles. The displacement and stress distribution of the mandible and articular disc were analyzed. With the bone-borne appliance the alveolar process area was displaced more than the basal bone area. The tooth-borne appliance displaced the mandibular body in a parallel manner and showed high level of the von Mises stress in the alveolar process and the ramal region as well as in the condylar neck area. The hybrid type showed medium amount of displacement and stress distribution compared with the bone-borne and tooth-borne type. At the articular disc the compressive stress was concentrated in the anteromedial and posterolateral area, and it was highest in the tooth-borne distractor, followed by hybrid appliance and bone-borne appliance. The tooth-borne distractor produced more parallel bony widening in the midsymphyseal area and larger expansion in the molar region; however, it induced higher stress concentration on the articular disc than the hybrid appliance and bone-borne appliance. Whether any long-term side effects on the temporomandibular joint are anticipated, especially in tooth-borne distractor, remains to be investigated.

25 CFR 173.12 - Services from project.

Code of Federal Regulations, 2011 CFR

2011-04-01

... BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER CONCESSIONS, PERMITS AND LEASES ON.... When the facilities of the project make it possible to supply water for domestic purposes, electricity... borne by the permittee and the work must be in accordance with standard practices and accepted by the...

25 CFR 173.12 - Services from project.

Code of Federal Regulations, 2014 CFR

2014-04-01

... BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER CONCESSIONS, PERMITS AND LEASES ON.... When the facilities of the project make it possible to supply water for domestic purposes, electricity... borne by the permittee and the work must be in accordance with standard practices and accepted by the...

25 CFR 173.12 - Services from project.

Code of Federal Regulations, 2012 CFR

2012-04-01

... BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER CONCESSIONS, PERMITS AND LEASES ON.... When the facilities of the project make it possible to supply water for domestic purposes, electricity... borne by the permittee and the work must be in accordance with standard practices and accepted by the...

25 CFR 173.12 - Services from project.

Code of Federal Regulations, 2013 CFR

2013-04-01

... BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER CONCESSIONS, PERMITS AND LEASES ON.... When the facilities of the project make it possible to supply water for domestic purposes, electricity... borne by the permittee and the work must be in accordance with standard practices and accepted by the...

Engine-induced structural-borne noise in a general aviation aircraft

NASA Technical Reports Server (NTRS)

Unruh, J. F.; Scheidt, D. C.; Pomerening, D. J.

1979-01-01

Structural borne interior noise in a single engine general aviation aircraft was studied to determine the importance of engine induced structural borne noise and to determine the necessary modeling requirements for the prediction of structural borne interior noise. Engine attached/detached ground test data show that engine induced structural borne noise is a primary interior noise source for the single engine test aircraft, cabin noise is highly influenced by responses at the propeller tone, and cabin acoustic resonances can influence overall noise levels. Results from structural and acoustic finite element coupled models of the test aircraft show that wall flexibility has a strong influence on fundamental cabin acoustic resonances, the lightweight fuselage structure has a high modal density, and finite element analysis procedures are appropriate for the prediction of structural borne noise.

A high-performance electric field detector for space missions

NASA Astrophysics Data System (ADS)

Badoni, D.; Ammendola, R.; Bertello, I.; Cipollone, P.; Conti, L.; De Santis, C.; Diego, P.; Masciantonio, G.; Picozza, P.; Sparvoli, R.; Ubertini, P.; Vannaroni, G.

2018-04-01

We present the prototype of an Electric Field Detector (EFD) for space applications, that has been developed in the framework of the Chinese-Italian collaboration on the CSES (China Seismo-Electromagnetic Satellite) forthcoming missions. In particular CSES-1 will be placed in orbit in the early 2018. The detector consists of spherical probes designed to be installed at the tips of four booms deployed from a 3-axes stabilized satellite. The instrument has been conceived for space-borne measurements of electromagnetic phenomena such as ionospheric waves, lithosphere-atmosphere-ionosphere-magnetosphere coupling and anthropogenic electromagnetic emissions. The detector allows to measure electric fields in a wide band of frequencies extending from quasi-DC up to about 4 MHz , with a sensitivity of the order of 1 μV / m in the ULF band. With these bandwidth and sensitivity, the described electric field detector represents a very performing and updated device for electric field measurements in space.

Rotor compound concept for designing an industrial HTS synchronous motor

NASA Astrophysics Data System (ADS)

Kashani, M.; Hosseina, M.; Sarrafan, K.; Darabi, A.

2013-06-01

Recently, producing power with smaller amount of losses become as a goal in our daily life. Today, large amount of energy waste in power networks all around the world. The main reason is “resistive electric equipments” of power networks. Since early 1980s, simultaneous with the development of high temperature superconductive (HTS) technology, superconductors gently attracted the mankind attentions. Using superconductive equipments instead of conventional resistive ones are result in salient electric loss reduction in power systems. Especially to reduce losses in power networks superconductive industrial rotating machines can potentially perform a significant role. In early recent century, first generation of HTS rotating machines was born. But unfortunately they have long way to penetrate the commercial markets yet. In HTS rotating machines the conventional copper made windings are replaced with the HTS superconductors. In this paper an industrial HTS synchronous motor with YBCO coated conductor field windings was designed. As a new approach, model was equipped with a compound rotor that includes both magnetic and non-magnetic materials. So, large amount of heavy iron made part was replaced by light non-magnetic material such as G-10 fiberglass. Furthermore, in this structure iron loss in rotor could be reduced to its lowest value. Also less weight and more air gap energy density were the additional advantages. Regarding zero electric loss production in field windings and less iron loss in rotor construction, this model potentially is more effective than the other iron made HTS motors.

Country of birth, parental background and self-rated health among adolescents: a population-based study.

PubMed

Lindström, Martin; Modén, Birgit; Rosvall, Maria

2014-12-01

The aim of this study was to investigate differences according to country of birth and parental country of birth, in relation to poor self-rated health (SRH), in Swedish adolescents. The Scania public health survey among children and adolescents, conducted in 2012, is a cross-sectional study including most pupils in grade 9 (15 years old), including in 32 of 33 municipalities. The participation rate was 83% (9,791 of 11,735). We performed logistic regressions to investigate the association between the students' country of birth, parental country of birth and poor SRH. Boys born outside Europe had an odds ratio (OR) 2.1 (1.6-2.8) of poor SRH in the unadjusted model, which was reduced to 0.7 (0.4-1.3) in the multiple model, as compared to boys born in Sweden with both or one parent born in Sweden. Boys born in Europe had an OR 0.4 (0.2-0.9) of poor SRH, after multiple adjustments. Girls born in Sweden with both parents born abroad, and girls born outside of Europe had significantly lower ORs of poor SRH in the multiple model. In particular, adjustment for socio-demographic and psychosocial factors reduced the ORs of poor SRH among boys, but did so to a lesser extent among girls. Differences in socio-demographic and psychosocial factors explained the higher odds of poor SRH among boys born outside of Europe. Girls born in Sweden with both parents born abroad, and girls born outside Europe, had significantly lower ORs of poor SRH. Our results indicate that there are gender differences in the factors behind poor self-rated health, according to the country-related background of adolescents in Sweden. © 2014 the Nordic Societies of Public Health.

Generalized Born-Oppenheimer treatment of Jahn-Teller systems in Hilbert spaces of arbitrary dimension: theory and application to a three-state model potential.

PubMed

Varandas, A J C; Sarkar, B

2011-05-14

Generalized Born-Oppenheimer equations including the geometrical phase effect are derived for three- and four-fold electronic manifolds in Jahn-Teller systems near the degeneracy seam. The method is readily extendable to N-fold systems of arbitrary dimension. An application is reported for a model threefold system, and the results are compared with Born-Oppenheimer (geometrical phase ignored), extended Born-Oppenheimer, and coupled three-state calculations. The theory shows unprecedented simplicity while depicting all features of more elaborated ones.

Using the Gravity Model to Estimate the Spatial Spread of Vector-Borne Diseases

PubMed Central

Barrios, José Miguel; Verstraeten, Willem W.; Maes, Piet; Aerts, Jean-Marie; Farifteh, Jamshid; Coppin, Pol

2012-01-01

The gravity models are commonly used spatial interaction models. They have been widely applied in a large set of domains dealing with interactions amongst spatial entities. The spread of vector-borne diseases is also related to the intensity of interaction between spatial entities, namely, the physical habitat of pathogens’ vectors and/or hosts, and urban areas, thus humans. This study implements the concept behind gravity models in the spatial spread of two vector-borne diseases, nephropathia epidemica and Lyme borreliosis, based on current knowledge on the transmission mechanism of these diseases. Two sources of information on vegetated systems were tested: the CORINE land cover map and MODIS NDVI. The size of vegetated areas near urban centers and a local indicator of occupation-related exposure were found significant predictors of disease risk. Both the land cover map and the space-borne dataset were suited yet not equivalent input sources to locate and measure vegetated areas of importance for disease spread. The overall results point at the compatibility of the gravity model concept and the spatial spread of vector-borne diseases. PMID:23202882

Using the gravity model to estimate the spatial spread of vector-borne diseases.

PubMed

Barrios, José Miguel; Verstraeten, Willem W; Maes, Piet; Aerts, Jean-Marie; Farifteh, Jamshid; Coppin, Pol

2012-11-30

The gravity models are commonly used spatial interaction models. They have been widely applied in a large set of domains dealing with interactions amongst spatial entities. The spread of vector-borne diseases is also related to the intensity of interaction between spatial entities, namely, the physical habitat of pathogens’ vectors and/or hosts, and urban areas, thus humans. This study implements the concept behind gravity models in the spatial spread of two vector-borne diseases, nephropathia epidemica and Lyme borreliosis, based on current knowledge on the transmission mechanism of these diseases. Two sources of information on vegetated systems were tested: the CORINE land cover map and MODIS NDVI. The size of vegetated areas near urban centers and a local indicator of occupation-related exposure were found significant predictors of disease risk. Both the land cover map and the space-borne dataset were suited yet not equivalent input sources to locate and measure vegetated areas of importance for disease spread. The overall results point at the compatibility of the gravity model concept and the spatial spread of vector-borne diseases.

Geoelectrical investigation of oil contaminated soils in former underground fuel base: Borne Sulinowo, NW Poland

NASA Astrophysics Data System (ADS)

Zogala, B.; Dubiel, R.; Zuberek, W. M.; Rusin-Zogala, M.; Steininger, M.

2009-07-01

The survey has been carried out in the area of 0.23 km2 of the former military underground fuel base. The oil derivative products were observed in excavations and the laboratory tests confirmed the occurrence of hydrocarbons (>C12) in soils. The purpose of the survey was to determine the spatial extent of the contamination. The studied area is covered by postglacial sediments: sands, gravels and till. The first water table was observed at a depth of 10-12 m. The detailed electromagnetic measurements with Geonics EM31-MK2 conductivity meter were performed in the whole area of the former fuel base. Obtained results were elaborated statistically and the map of apparent electrical conductivity to a depth of 6 m was created. Many local low conductivity anomalies were observed. The measurements with Geonics EM34-3XL were performed along one A-A' profile and 1D electromagnetic modelling along with this profile was calculated to obtain the electrical conductivity cross-section to a depth of 30 m. Two-dimensional electrical resistivity imaging measurements were carried out along the same profile and the resistivity cross-section to a depth of 20 m was performed. Both conducivity and resistivity cross-sections show anomalous zones. The zones correlate with oil contaminated zones very well.

Non-Markovian quantum Brownian motion in one dimension in electric fields

NASA Astrophysics Data System (ADS)

Shen, H. Z.; Su, S. L.; Zhou, Y. H.; Yi, X. X.

2018-04-01

Quantum Brownian motion is the random motion of quantum particles suspended in a field (or an effective field) resulting from their collision with fast-moving modes in the field. It provides us with a fundamental model to understand various physical features concerning open systems in chemistry, condensed-matter physics, biophysics, and optomechanics. In this paper, without either the Born-Markovian or rotating-wave approximation, we derive a master equation for a charged-Brownian particle in one dimension coupled with a thermal reservoir in electric fields. The effect of the reservoir and the electric fields is manifested as time-dependent coefficients and coherent terms, respectively, in the master equation. The two-photon correlation between the Brownian particle and the reservoir can induce nontrivial squeezing dynamics to the particle. We derive a current equation including the source from the driving fields, transient current from the system flowing into the environment, and the two-photon current caused by the non-rotating-wave term. The presented results then are compared with that given by the rotating-wave approximation in the weak-coupling limit, and these results are extended to a more general quantum network involving an arbitrary number of coupled-Brownian particles. The presented formalism might open a way to better understand exactly the non-Markovian quantum network.

Model Simulation of Ionosphere Electron Density with Dynamic Transportation and Mechanism of Sporadic E Layers in Lower Part of Ionosphere

NASA Astrophysics Data System (ADS)

Lin, Y. C.; Chu, Y. H.

2015-12-01

There are many physical theories responsible for explanation the generation mechanism of sporadic E (Es) plasma irregularities. In middle latitude, it's generally believed that sporadic E layers occur in vertical ion convergent areas driven by horizontal neutral wind shear. The sporadic E layers appear characteristic of abundant metallic ion species (i.e., Fe+, Mg+, Na+), that lifetime are longer than molecular ions by a factor of several orders, have been demonstrated by rocket-borne mass spectrometric measurements. On the basic of the GPS Radio Occultation (RO), using the scintillations of the GPS signal-to-noise ratio and intense fluctuation of excess phase, the global and seasonal sporadic E layers occurrence rates could be retrieved. In our previous study we found there is averaged 10 kilometers shift in height between the COSMIC-retrieved sporadic E layer occurrence rate and the sporadic E occurrence rate modeled from considering the convergence/divergence of Fe+ vertical flux. There are many reasons that maybe result in the altitude differences, e.g., tidal wind with phase shift, electric field driven force, iron species distributions. In this research, the quantitative analyses for electric field drives Es layers translations in vertical direction are presented. The tidal wind driven sporadic E layers have been simulating by modeling several nonmetallic ions (O+(4S), O+(2D), O+(2p), N+, N2+, O2+, NO+) and metallic ions (Fe+, FeO2+, FeN2+, FeO+) with wind shear transportation. The simulation result shows the Fe+ particles accumulate at zonal wind shear convergent regions and form the thin sporadic E layers. With the electric field taking into account, the whole shape of sporadic E layers vertical shift 2~5 km that depending on what magnitude and direction of electric field is added.

Vector-Borne Pathogen and Host Evolution in a Structured Immuno-Epidemiological System.

PubMed

Gulbudak, Hayriye; Cannataro, Vincent L; Tuncer, Necibe; Martcheva, Maia

2017-02-01

Vector-borne disease transmission is a common dissemination mode used by many pathogens to spread in a host population. Similar to directly transmitted diseases, the within-host interaction of a vector-borne pathogen and a host's immune system influences the pathogen's transmission potential between hosts via vectors. Yet there are few theoretical studies on virulence-transmission trade-offs and evolution in vector-borne pathogen-host systems. Here, we consider an immuno-epidemiological model that links the within-host dynamics to between-host circulation of a vector-borne disease. On the immunological scale, the model mimics antibody-pathogen dynamics for arbovirus diseases, such as Rift Valley fever and West Nile virus. The within-host dynamics govern transmission and host mortality and recovery in an age-since-infection structured host-vector-borne pathogen epidemic model. By considering multiple pathogen strains and multiple competing host populations differing in their within-host replication rate and immune response parameters, respectively, we derive evolutionary optimization principles for both pathogen and host. Invasion analysis shows that the [Formula: see text] maximization principle holds for the vector-borne pathogen. For the host, we prove that evolution favors minimizing case fatality ratio (CFR). These results are utilized to compute host and pathogen evolutionary trajectories and to determine how model parameters affect evolution outcomes. We find that increasing the vector inoculum size increases the pathogen [Formula: see text], but can either increase or decrease the pathogen virulence (the host CFR), suggesting that vector inoculum size can contribute to virulence of vector-borne diseases in distinct ways.

In situ measurements and radar observations of a severe storm - Electricity, kinematics, and precipitation

NASA Technical Reports Server (NTRS)

Byrne, G. J.; Few, A. A.; Stewart, M. F.; Conrad, A. C.; Torczon, R. L.

1987-01-01

Electric field measurements made inside a multicell severe storm in Oklahoma in 1983 with a balloon-borne instrument are presented. The properties of the electric charge regions, such as altitude, thickness, and charge concentrations, are studied. These measurements are analzyed with meteorological measurements of temperature and humidity, and balloon tracking and radar observations. The relation between the electric charge structure and the precipitation and kinematic features of the storm is examined. The data reveal that the cell exhibits a bipolar charge structure with negative charge below positive charge. The average charge concentrations of the two regions are estimated as -1.2 and 0.15 nC/cu m, respectively; the upper positive charge is about 6 km in vertical extent, and the lower negative charge is less than 1 km in vertical extent.

Comparisons of the topographic characteristics and electrical charge distributions among Babesia-infected erythrocytes and extraerythrocytic merozoites using AFM

USDA-ARS?s Scientific Manuscript database

Tick-borne Babesia parasites are responsible for costly diseases worldwide. Improved control and prevention tools are urgently needed, but development of such tools is limited by numerous gaps in knowledge of the parasite-host relationships. We hereby used atomic force microscopy (AFM) and Kelvin pr...

The Born-Infeld vortices induced from a generalized Higgs mechanism.

PubMed

Han, Xiaosen

2016-04-01

We construct self-dual Born-Infeld vortices induced from a generalized Higgs mechanism. Two specific models of the theory are of focused interest where the Higgs potential is either of a | ϕ | 4 - or | ϕ | 6 -type. For the | ϕ | 4 -model, we obtain a sharp existence and uniqueness theorem for doubly periodic and planar vortices. For doubly periodic solutions, a necessary and sufficient condition for the existence is explicitly derived in terms of the vortex number, the Born-Infeld parameter, and the size of the periodic lattice domain. For the | ϕ | 6 -model, we show that both topological and non-topological vortices are present. This new phenomenon distinguishes the model from the classical Born-Infeld-Higgs theory studied earlier in the literature. A series of results regarding doubly periodic, topological, and non-topological vortices in the | ϕ | 6 -model are also established.

Effects of gestational age on brain volume and cognitive functions in generally healthy very preterm born children during school-age: A voxel-based morphometry study.

PubMed

Lemola, Sakari; Oser, Nadine; Urfer-Maurer, Natalie; Brand, Serge; Holsboer-Trachsler, Edith; Bechtel, Nina; Grob, Alexander; Weber, Peter; Datta, Alexandre N

2017-01-01

To determine whether the relationship of gestational age (GA) with brain volumes and cognitive functions is linear or whether it follows a threshold model in preterm and term born children during school-age. We studied 106 children (M = 10 years 1 month, SD = 16 months; 40 females) enrolled in primary school: 57 were healthy very preterm children (10 children born 24-27 completed weeks' gestation (extremely preterm), 14 children born 28-29 completed weeks' gestation, 19 children born 30-31 completed weeks' gestation (very preterm), and 14 born 32 completed weeks' gestation (moderately preterm)) all born appropriate for GA (AGA) and 49 term-born children. Neuroimaging involved voxel-based morphometry with the statistical parametric mapping software. Cognitive functions were assessed with the WISC-IV. General Linear Models and multiple regressions were conducted controlling age, sex, and maternal education. Compared to groups of children born 30 completed weeks' gestation and later, children born <28 completed weeks' gestation had less gray matter volume (GMV) and white matter volume (WMV) and poorer cognitive functions including decreased full scale IQ, and processing speed. Differences in GMV partially mediated the relationship between GA and full scale IQ in preterm born children. In preterm children who are born AGA and without major complications GA is associated with brain volume and cognitive functions. In particular, decreased brain volume becomes evident in the extremely preterm group (born <28 completed weeks' gestation). In preterm children born 30 completed weeks' gestation and later the relationship of GA with brain volume and cognitive functions may be less strong as previously thought.

A comparison of helicopter-borne electromagnetic systems for hydrogeologic studies

USGS Publications Warehouse

Bedrosian, Paul A.; Schamper, Cyril; Auken, Esben

2016-01-01

The increased application of airborne electromagnetic surveys to hydrogeological studies is driving a demand for data that can consistently be inverted for accurate subsurface resistivity structure from the near surface to depths of several hundred metres. We present an evaluation of three commercial airborne electromagnetic systems over two test blocks in western Nebraska, USA. The selected test blocks are representative of shallow and deep alluvial aquifer systems with low groundwater salinity and an electrically conductive base of aquifer. The aquifer units show significant lithologic heterogeneity and include both modern and ancient river systems. We compared the various data sets to one another and inverted resistivity models to borehole lithology and to ground geophysical models. We find distinct differences among the airborne electromagnetic systems as regards the spatial resolution of models, the depth of investigation, and the ability to recover near-surface resistivity variations. We further identify systematic biases in some data sets, which we attribute to incomplete or inexact calibration or compensation procedures.

The Vibration Ring. Phase 1; [Seedling Fund

NASA Technical Reports Server (NTRS)

Asnani, Vivake M.; Krantz, Timothy L.; Delap, Damon C.; Stringer, David B.

2014-01-01

The vibration ring was conceived as a driveline damping device to prevent structure-borne noise in machines. It has the appearance of a metal ring, and can be installed between any two driveline components like an ordinary mechanical spacer. Damping is achieved using a ring-shaped piezoelectric stack that is poled in the axial direction and connected to an electrical shunt circuit. Surrounding the stack is a metal structure, called the compression cage, which squeezes the stack along its poled axis when excited by radial driveline forces. The stack in turn generates electrical energy, which is either dissipated or harvested using the shunt circuit. Removing energy from the system creates a net damping effect. The vibration ring is much stiffer than traditional damping devices, which allows it to be used in a driveline without disrupting normal operation. In phase 1 of this NASA Seedling Fund project, a combination of design and analysis was used to examine the feasibility of this concept. Several designs were evaluated using solid modeling, finite element analysis, and by creating prototype hardware. Then an analytical model representing the coupled electromechanical response was formulated in closed form. The model was exercised parametrically to examine the stiffness and loss factor spectra of the vibration ring, as well as simulate its damping effect in the context of a simplified driveline model. The results of this work showed that this is a viable mechanism for driveline damping, and provided several lessons for continued development.

A new probability distribution model of turbulent irradiance based on Born perturbation theory

NASA Astrophysics Data System (ADS)

Wang, Hongxing; Liu, Min; Hu, Hao; Wang, Qian; Liu, Xiguo

2010-10-01

The subject of the PDF (Probability Density Function) of the irradiance fluctuations in a turbulent atmosphere is still unsettled. Theory reliably describes the behavior in the weak turbulence regime, but theoretical description in the strong and whole turbulence regimes are still controversial. Based on Born perturbation theory, the physical manifestations and correlations of three typical PDF models (Rice-Nakagami, exponential-Bessel and negative-exponential distribution) were theoretically analyzed. It is shown that these models can be derived by separately making circular-Gaussian, strong-turbulence and strong-turbulence-circular-Gaussian approximations in Born perturbation theory, which denies the viewpoint that the Rice-Nakagami model is only applicable in the extremely weak turbulence regime and provides theoretical arguments for choosing rational models in practical applications. In addition, a common shortcoming of the three models is that they are all approximations. A new model, called the Maclaurin-spread distribution, is proposed without any approximation except for assuming the correlation coefficient to be zero. So, it is considered that the new model can exactly reflect the Born perturbation theory. Simulated results prove the accuracy of this new model.

Carbon Dioxide Fluctuations Are Associated with Changes in Cerebral Oxygenation and Electrical Activity in Infants Born Preterm.

PubMed

Dix, Laura Marie Louise; Weeke, Lauren Carleen; de Vries, Linda Simone; Groenendaal, Floris; Baerts, Willem; van Bel, Frank; Lemmers, Petra Maria Anna

2017-08-01

To evaluate the effects of acute arterial carbon dioxide partial pressure changes on cerebral oxygenation and electrical activity in infants born preterm. This retrospective observational study included ventilated infants born preterm with acute fluctuations of continuous end-tidal CO 2 (etCO 2 ) as a surrogate marker for arterial carbon dioxide partial pressure, during the first 72 hours of life. Regional cerebral oxygen saturation and fractional tissue oxygen extraction were monitored with near-infrared spectroscopy. Brain activity was monitored with 2-channel electroencephalography. Spontaneous activity transients (SATs) rate (SATs/minute) and interval between SATs (in seconds) were calculated. Ten-minute periods were selected for analysis: before, during, and after etCO 2 fluctuations of ≥5  mm Hg. Thirty-eight patients (mean ± SD gestational age of 29 ± 1.8 weeks) were included, with 60 episodes of etCO 2 increase and 70 episodes of etCO 2 decrease. During etCO 2 increases, brain oxygenation increased (regional cerebral oxygen saturation increased, fractional tissue oxygen extraction decreased; P < .01) and electrical activity decreased (SATs/minute decreased, interval between SATs increased; P < .01). All measures recovered when etCO 2 returned to baseline. During etCO 2 decreases, brain oxygenation decreased (regional cerebral oxygen saturation decreased, fractional tissue oxygen extraction decreased; P < .01) and brain activity increased (SATs/minute increased, P < .05), also with recovery after return of etCO 2 to baseline. An acute increase in etCO 2 is associated with increased cerebral oxygenation and decreased brain activity, whereas an acute decrease is associated with decreased cerebral oxygenation and slightly increased brain activity. Combining continuous CO 2 monitoring with near-infrared spectroscopy may enable the detection of otherwise undetected fluctuations in arterial carbon dioxide partial pressure that may be harmful to the neonatal brain. Copyright © 2017 Elsevier Inc. All rights reserved.

The importance of excluded solvent volume effects in computing hydration free energies.

PubMed

Yang, Pei-Kun; Lim, Carmay

2008-11-27

Continuum dielectric methods such as the Born equation have been widely used to compute the electrostatic component of the solvation free energy, DeltaG(solv)(elec), because they do not need to include solvent molecules explicitly and are thus far less costly compared to molecular simulations. All of these methods can be derived from Gauss Law of Maxwell's equations, which yields an analytical solution for the solvation free energy, DeltaG(Born), when the solute is spherical. However, in Maxwell's equations, the solvent is assumed to be a structureless continuum, whereas in reality, the near-solute solvent molecules are highly structured unlike far-solute bulk solvent. Since we have recently reformulated Gauss Law of Maxwell's equations to incorporate the near-solute solvent structure by considering excluded solvent volume effects, we have used it in this work to derive an analytical solution for the hydration free energy of an ion. In contrast to continuum solvent models, which assume that the normalized induced solvent electric dipole density P(n) is constant, P(n) mimics that observed from simulations. The analytical formula for the ionic hydration free energy shows that the Born radius, which has been used as an adjustable parameter to fit experimental hydration free energies, is no longer ill defined but is related to the radius and polarizability of the water molecule, the hydration number, and the first peak position of the solute-solvent radial distribution function. The resulting DeltaG(solv)(elec) values are shown to be close to the respective experimental numbers.

VLF Trimpi modelling on the path NWC-Dunedin using both finite element and 3D Born modelling

NASA Astrophysics Data System (ADS)

Nunn, D.; Hayakawa, K. B. M.

1998-10-01

This paper investigates the numerical modelling of VLF Trimpis, produced by a D region inhomogeneity on the great circle path. Two different codes are used to model Trimpis on the path NWC-Dunedin. The first is a 2D Finite Element Method Code (FEM), whose solutions are rigorous and valid in the strong scattering or non-Born limit. The second code is a 3D model that invokes the Born approximation. The predicted Trimpis from these codes compare very closely, thus confirming the validity of both models. The modal scattering matrices for both codes are analysed in some detail and are found to have a comparable structure. They indicate strong scattering between the dominant TM modes. Analysis of the scattering matrix from the FEM code shows that departure from linear Born behaviour occurs when the inhomogeneity has a horizontal scale size of about 100 km and a maximum electron density enhancement at 75 km altitude of about 6 electrons.

A population-based study of tuberculosis epidemiology and innovative service delivery in Canada.

PubMed

Jensen, M; Lau, A; Langlois-Klassen, D; Boffa, J; Manfreda, J; Long, R

2012-01-01

To compare and interpret tuberculosis (TB) incidence rates in a Canadian population across two decennials (1989-1998 and 1999-2008) as a benchmark for World Health Organization targets and the long-term goal of TB elimination. The population under study was served by two urban clinics in the first decennial and two urban and one provincial clinic in the second. TB rates among Status Indians, Canadian-born 'others' and the foreign-born were estimated using provincial and national databases. Program performance was measured in on-reserve Status Indians in each decennial. In each decennial, the incidence rate in Status Indians and the foreign-born was greater than that in the Canadian-born 'others'; respectively 27.7 and 33.0 times in Status Indians, and 8.0 and 20.9 times in the foreign-born. Between decennials, the rate fell by 56% in Status Indians, 58% in Canadian-born 'others', and 18% in the foreign-born. On-reserve Status Indians had higher rates than off-reserve Status Indians, and the three-clinic model out-performed the two-clinic model among those on-reserve. Rates in the foreign-born varied by World Bank region, and were highest among those from Africa and Asia. Status Indians and the foreign-born are at increased risk of TB in Canada. Significant progress towards TB elimination has been made in Status Indians but not in the foreign-born.

Simulating the spread of malaria using a generic transmission model for mosquito-borne infectious diseases

NASA Astrophysics Data System (ADS)

Kon, Cynthia Mui Lian; Labadin, Jane

2016-06-01

Malaria is a critical infection caused by parasites which are spread to humans through mosquito bites. Approximately half of the world's population is in peril of getting infected by malaria. Mosquito-borne diseases have a standard behavior where they are transmitted in the same manner, only through vector mosquito. Taking this into account, a generic spatial-temporal model for transmission of multiple mosquito-borne diseases had been formulated. Our interest is to reproduce the actual cases of different mosquito-borne diseases using the generic model and then predict future cases so as to improve control and target measures competently. In this paper, we utilize notified weekly malaria cases in four districts in Sarawak, Malaysia, namely Kapit, Song, Belaga and Marudi. The actual cases for 36 weeks, which is from week 39 in 2012 to week 22 in 2013, are compared with simulations of the generic spatial-temporal transmission mosquito-borne diseases model. We observe that the simulation results display corresponding result to the actual malaria cases in the four districts.

The economics of nuclear power

NASA Astrophysics Data System (ADS)

Horst, Ronald L.

We extend economic analysis of the nuclear power industry by developing and employing three tools. They are (1) compilation and unification of operating and accounting data sets for plants and sites, (2) an abstract industry model with major economic agents and features, and (3) a model of nuclear power plant operators. We build a matched data set to combine dissimilar but mutually dependant bodies of information. We match detailed information on the activities and conditions of individual plants to slightly more aggregated financial data. Others have exploited the data separately, but we extend the sets and pool available data sets. The data reveal dramatic changes in the industry over the past thirty years. The 1980s proved unprofitable for the industry. This is evident both in the cost data and in the operator activity data. Productivity then improved dramatically while cost growth stabilized to the point of industry profitability. Relative electricity prices may be rising after nearly two decades of decline. Such demand side trends, together with supply side improvements, suggest a healthy industry. Our microeconomic model of nuclear power plant operators employs a forward-looking component to capture the information set available to decision makers and to model the decision-making process. Our model includes features often overlooked elsewhere, including electricity price equations and liability. Failure to account for changes in electricity price trends perhaps misled earlier scholars, and they attributed to other causes the effects on profits of changing price structures. The model includes potential losses resulting from catastrophic nuclear accidents. Applications include historical simulations and forecasts. Nuclear power involves risk, and accident costs are borne both by plant owners and the public. Authorities regulate the industry and balance conflicting desires for economic gain and safety. We construct an extensible model with regulators, plant operators, insurance companies, and consumers. The model possesses key attributes of the industry seldom found in combination elsewhere. We then add additional details to make the model truer to reality. The work extends and corrects existing literature on the definition, effects, and magnitudes of implicit subsidies resulting from liability limits.

COMMUNITY LEVEL ANALYSIS OF VECTOR-BORNE DISEASE

EPA Science Inventory

Ecological community structure is particularly important in vector-borne zoonotic diseases with complex life cycles. Single population models, such as the so-called Ross-Macdonald model (Baily, 1982), have been important in developing and characterizing our current understanding...

Positron Lifetime Modulation by Electric Field Induced Positronium Formation on a Gold Surface

DTIC Science & Technology

2012-03-22

Angular Momentum (3) ......................................................................... 11 Stopping Power (4...isotope from which it was born, diffused into the material before annihilation occurred. 6 The radioisotope used in this experiment is Na-22 which...that positrons may be useful in studying the internal structure of a wide variety of materials. The radioisotope positron source used in this

Immigration, race/ethnicity, and social and economic factors as predictors of breastfeeding initiation.

PubMed

Celi, Ann C; Rich-Edwards, Janet W; Richardson, Marcie K; Kleinman, Ken P; Gillman, Matthew W

2005-03-01

To determine the impact of immigration status as well as race/ethnicity and social and economic factors on breastfeeding initiation. Cohort. Multisite group practice in eastern Massachusetts. One thousand eight hundred twenty-nine pregnant women prospectively followed up in Project Viva. Whether the participant breastfed her infant. The overall breastfeeding initiation rate was 83%. In multivariate models that included race/ethnicity and social, economic, and demographic factors, foreign-born women were more likely to initiate breastfeeding than US-born women (odds ratio [OR], 3.2 [95% confidence interval (CI), 2.0-5.2]). In models stratified by both race/ethnicity and immigration status, and further adjusted for whether the mother herself was breastfed as an infant and the mother's parents' immigration status, US-born and foreign-born black and Hispanic women initiated breastfeeding at rates at least as high as US-born white women (US-born black vs US-born white women, OR, 1.2 [95% CI, 0.8-1.9], US-born Hispanic vs US-born white women, OR, 1.1 [95% CI, 0.6-1.9], foreign-born black vs US-born white women, OR, 2.6 [95% CI, 1.1-6.0], and foreign-born Hispanic vs US-born white women, OR, 1.8 [95% CI, 0.7-4.8]). Calculations of predicted prevalences showed that, for example, the 2.6-fold increase in odds for the foreign-born black vs US-born white women translated to an increase in probability of approximately 1.4. Higher maternal education and household income also predicted higher initiation rates. Immigration status was strongly associated with increased breastfeeding initiation in this cohort, implying that cultural factors are important in the decision to breastfeed. Immigrants of all races/ethnicities initiated breastfeeding more often than their US-born counterparts. In addition, US-born minority groups initiated breastfeeding at rates at least as high as their white counterparts, likely due in part to high levels of education and income as well as to access to a medical care system that explicitly supports breastfeeding.

Disparities in Health Care Coverage Among U.S. Born and Mexican/Central American Born Labor Workers in the U.S.

PubMed

Hammig, Bart; Henry, Jean; Davis, Donna

2018-01-31

We examined health insurance coverage among U.S. and Mexican/Central American (M/CA) born labor workers living in the U.S. Using data from the 2010-2015 National Health Interview Survey, we employed logistic regression models to examine health insurance coverage and covariates among U.S. and M/CA born labor workers. Prevalence ratios between U.S. and M/CA born workers were also obtained. U.S. born workers had double the prevalence of insurance coverage. Regarding private insurance coverage, U.S. born workers had a higher prevalence of coverage compared to their M/CA born counterparts. Among foreign born workers with U.S. citizenship, the odds of having insurance coverage was greater than that of noncitizens. Additionally, those who had lived in the U.S. for 10 or more years had higher odds of having health insurance coverage. Disparities in health care coverage exist between U.S. born and foreign born labor workers.

Interpregnancy interval and risk of autistic disorder.

PubMed

Gunnes, Nina; Surén, Pål; Bresnahan, Michaeline; Hornig, Mady; Lie, Kari Kveim; Lipkin, W Ian; Magnus, Per; Nilsen, Roy Miodini; Reichborn-Kjennerud, Ted; Schjølberg, Synnve; Susser, Ezra Saul; Øyen, Anne-Siri; Stoltenberg, Camilla

2013-11-01

A recent California study reported increased risk of autistic disorder in children conceived within a year after the birth of a sibling. We assessed the association between interpregnancy interval and risk of autistic disorder using nationwide registry data on pairs of singleton full siblings born in Norway. We defined interpregnancy interval as the time from birth of the first-born child to conception of the second-born child in a sibship. The outcome of interest was autistic disorder in the second-born child. Analyses were restricted to sibships in which the second-born child was born in 1990-2004. Odds ratios (ORs) were estimated by fitting ordinary logistic models and logistic generalized additive models. The study sample included 223,476 singleton full-sibling pairs. In sibships with interpregnancy intervals <9 months, 0.25% of the second-born children had autistic disorder, compared with 0.13% in the reference category (≥ 36 months). For interpregnancy intervals shorter than 9 months, the adjusted OR of autistic disorder in the second-born child was 2.18 (95% confidence interval 1.42-3.26). The risk of autistic disorder in the second-born child was also increased for interpregnancy intervals of 9-11 months in the adjusted analysis (OR = 1.71 [95% CI = 1.07-2.64]). Consistent with a previous report from California, interpregnancy intervals shorter than 1 year were associated with increased risk of autistic disorder in the second-born child. A possible explanation is depletion of micronutrients in mothers with closely spaced pregnancies.

A coordinated study of a storm system over the South American continent. 1. Weather information and quasi-DC stratospheric electric field data

NASA Astrophysics Data System (ADS)

Pinto, O.; Pinto, I. R. C. A.; Gin, R. B. B.; Mendes, O.

1992-11-01

This paper reports on a coordinated campaign conducted in Brazil, December 13, 1989, to study the electrical signatures associated with a large storm system over the South American continent. Inside the storm, large convective cells developed extending up to the tropopause, as revealed from meteorological balloon soundings. Quasi-DC vertical electric field and temperature were measured by zero-pressure balloon-borne payload launched from Cachoeira Paulista, Brazil. The data were supported by radar and GOES satellite observations, as well as by a lightning position and tracking system (LPATS). The analysis of infrared imagery supports the general tendency for lightning strikes to be near to but not exactly under the coldest cloud tops. In turn, the radar maps located the strikes near to but outside of the most intense areas of precipitation (reflectivity levels above 40 dBz). The balloon altitude and stratospheric temperature show significant variations in association with the storm. The quasi-DC vertical electric field remained almost during the whole flight in a reversed direction relative to the usual fair weather downward orientation with values as large as 4 V/m. A simple calculation based on a static dipole model of electrical cloud structure gives charges of some tens of coulombs. In contrast with most electric field measurements in other regions, no indication of an intensification of the vertical field in the downward fair weather orientation was observed. This fact is in agreement with past observations in the South American region and seems to be related to a particular type of storm that would occur with more frequency in this region. If so, such a difference may have an important role in the global atmospheric electrical circuit, considering that South America is believed to give a significant current contribution to the global circuit.

Prevalence of disability among US- and foreign-born Arab Americans: results from the 2000 US Census.

PubMed

Dallo, Florence J; Al Snih, Soham; Ajrouch, Kristine J

2009-01-01

Although the prevalence of disability for various racial and ethnic groups has been documented, little attention has been paid to Arab Americans in the United States. We estimated the age- and sex-adjusted prevalence of disability among older Arab Americans and examined the association between nativity status and self-reported physical and self-care disability before and after controlling for covariates. We used data from the 5% Public Use Microdata Samples of the 2000 US Census. Our sample included 4,225 individuals 65 years of age and older who identified with an Arab ancestry. Of these, 2,280 were foreign-born and 1,945 were US-born. The age- and sex-adjusted prevalence of having a physical disability was 31.2% for foreign- and 23.4% for US-born older Arab Americans, and the age- and sex- adjusted prevalence of having a self-care disability was 13.5% for foreign- and 6.8% for US-born Arab Americans. Iraqis reported the highest estimates for both disabilities (physical, 36.2%; self-care, 19.8%) compared to other Arab ethnic groups. In the crude model, foreign-born Arab Americans were more likely (OR=1.32; 95% CI=1.28, 1.36) to report a physical disability compared to US-born Arab Americans. When adjusting for English language ability in the final model, the odds of having a physical disability for foreign-born Arab Americans was protective compared to US-born Arab Americans (OR=0.92; 95% CI=0.88, 0.96). In the crude model, foreign-born Arab Americans were 1.82 times (95% CI=1.74, 1.90) more likely to report a self-care disability compared to US-born Arab Americans. In the fully adjusted model, this association was slightly attenuated (OR=1.32; 95% CI=1.24, 1.41). These findings indicate English language ability is associated with variations in reporting a physical disability. Future studies should include better measures of acculturation. Arab Americans are heterogeneous and should be disaggregated both by subgroups and from the white category in order to reveal a more accurate health and disease status profile for these groups. These efforts will assist in tailoring more effective interventions in reducing or preventing disability among Arab Americans 65 years of age and older. Copyright 2008 S. Karger AG, Basel.

Young adult outcomes of children born to teen mothers: effects of being born during their teen or later years.

PubMed

Lipman, Ellen L; Georgiades, Katholiki; Boyle, Michael H

2011-03-01

Children of teen mothers exhibit adverse outcomes through adolescence. It is unclear whether these adverse outcomes extend to adulthood and apply to all of her children, or only those born when she was a teen. We examine the associations between young adult functioning and being born to a teen mother aged ≤20 years at the time of birth (current teen), and being born to a teen mother later in her life (>21 years, prior teen). The 1983 Ontario Child Health Study (OCHS) and 2001 follow-up are used, including 2,355 participants 4 to 16 years old in 1983 with 2001 data. Using multilevel modeling we assessed the association between being born to a current versus prior teen mother, relative to a nonteen mother, and 2001 outcomes, controlling for individual and family level characteristics assessed in childhood. Being born to a teen mother (versus a nonteen mother) is associated with poorer educational achievement, life satisfaction, and personal income. Accounting for time of sample children's birth in teen mothers' lives, individuals born to current and prior teen mothers showed a ~0.8-year educational deficit, relative to individuals born to nonteen mothers in fully adjusted models. Individuals born to current teen mothers reported lower life satisfaction and personal income (-$7,262). There were no significant group differences at follow-up in mental or physical health between individuals born to nonteen mothers and those born to current or prior teen mothers. Although being born to a teen mother exerts a pervasive adverse effect on educational attainment, the adverse effects on life satisfaction and personal income appear to be selective for individuals born to a current teen mother. Further research is required to understand these differential effects. Copyright © 2011 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Dyadic contrast function and quadratic forward model for radio frequency tomography

NASA Astrophysics Data System (ADS)

Picco, Vittorio

Radio Frequency Tomography is an underground imaging technology that aims to reconstruct extended, deeply buried objects such as tunnels or Underground Facilities (UGF). A network of sensors collects scattered electromagnetic field samples, which are processed to obtain 2D or 3D images of the complex dielectric permittivity profile of the volume under investigation. Unlike systems such as Synthetic Aperture Radar (SAR) or Ground Penetrating Radar (GPR) which normally employ wide-band pulses, RF Tomography uses Continuous Wave (CW) signals to illuminate the scene. The information about the target is not retrieved by relying on bandwidth but by exploiting spatial, frequency and/or polarization diversity. Interestingly, RF Tomography can be readily adapted to obtain images of targets in free space. In this context, in the Andrew Electromagnetics Laboratory of the University of Illinois at Chicago, a measurement system aimed to validate experimentally the performance of RF Tomography has been designed and built. Experimental data have been used to validate its forward model, different inversion algorithms, its performance in terms of resolution and the ability of the system to distinguish between metallic and non-metallic targets. In the specific case of imaging of metallic targets, this thesis proposes to extend the capabilities of RF Tomography by introducing a dyadic permittivity contrast. Electromagnetic scattering from a thin, wire-like object placed in free space with its main axis at an angle with respect to the incident electric field is studied. It is possible to show that for this configuration a fundamental difference exists between a metallic and a dielectric object. This phenomenon can be modeled into Maxwell's equations by using a dyadic permittivity contrast, as it is commonly done when studying crystals. As a result a new formulation of the RF Tomography forward model is obtained, based on a dyadic contrast function. Reconstruction of this dyad allows to estimate not only the location and shape, but also the spatial orientation of the target. In addition, this dissertation proposes an alternative modification of the forward model which removes some limitations caused by the Born approximation. Traditionally, the Born approximation is used to linearize the inherently non-linear forward model. This approximation is valid if the scatterer is small and does not interact strongly with other objects. A quadratic forward model represents a more correct formulation of the scattering phenomenon, and it allows to attempt quantitative reconstruction. Numerical results are presented to highlight the advantages that such a formulation provides over the Born approximation.

An integrated model to simulate the scattering of ultrasounds by inclusions in steels.

PubMed

Darmon, Michel; Calmon, Pierre; Bèle, Bertrand

2004-04-01

We present a study performed to model and predict the ultrasonic response of alumina inclusions in steels. The Born and the extended quasistatic approximations have been applied and modified to improve their accuracy in the framework of this application. The modified Born approximation, called "doubly distorted wave (D(2)W) Born approximation" allowing to deal with various inclusion shapes, has been selected to be implemented in the CIVA software. The model reliability has been evaluated by comparison with Ying and Truell's exact analytical solution. In parallel, measurements have been carried out upon both natural and artificial alumina inclusions.

Neurogenesis and ontogeny of specific cell phenotypes within the hamster suprachiasmatic nucleus.

PubMed

Antle, Michael C; LeSauter, Joseph; Silver, Rae

2005-06-09

The hamster suprachiasmatic nucleus (SCN) is anatomically and functionally heterogeneous. A group of cells in the SCN shell, delineated by vasopressin-ergic neurons, are rhythmic with respect to Period gene expression and electrical activity but do not receive direct retinal input. In contrast, some cells in the SCN core, marked by neurons containing calbindin-D28k, gastrin-releasing peptide (GRP), substance P (SP), and vasoactive intestinal polypeptide (VIP), are not rhythmic with respect to Period gene expression and electrical activity but do receive direct retinal input. Examination of the timing of neurogenesis using bromodeoxyuridine indicates that SCN cells are born between embryonic day 9.5 and 12.5. Calbindin, GRP, substance P, and VIP cells are born only during early SCN neurogenesis, between embryonic days 9.5-11.0. Vasopressin cells are born over the whole period of SCN neurogenesis, appearing as late as embryonic day 12.5. Examination of the ontogeny of peptide expression in these cell types reveals transient expression of calbindin in a cluster of dorsolateral SCN cells on postnatal days 1-2. The adult pattern of calbindin expression is detected in a different ventrolateral cell cluster starting on postnatal day 2. GRP and SP expression appear on postnatal day 8 and 10, respectively, after the retinohypothalamic tract has innervated the SCN. In summary, the present study describes the ontogeny-specific peptidergic phenotypes in the SCN and compares these developmental patterns to previously identified patterns in the appearance of circadian functions. These comparisons suggest the possibility that these coincident appearances may be causally related, with the direction of causation to be determined.

Introducing time-dependent molecular fields: a new derivation of the wave equations

NASA Astrophysics Data System (ADS)

Baer, Michael

2018-02-01

This article is part of a series of articles trying to establish the concept molecular field. The theory that induced us to introduce this novel concept is based on the Born-Huang expansion as applied to the Schroedinger equation that describes the interaction of a molecular system with an external electric field. Assuming the molecular system is made up of two coupled adiabatic states the theory leads from a single spatial curl equation, two space-time curl equations and one single space-time divergent equation to a pair of decoupled wave equations usually encountered within the theory of fields. In the present study, just like in the previous study [see Baer et al., Mol. Phys. 114, 227 (2016)] the wave equations are derived for an electric field having two features: (a) its intensity is high enough; (b) its duration is short enough. Although not all the findings are new the derivation, in the present case, is new, straightforward, fluent and much friendlier as compared to the previous one and therefore should be presented again. For this situation the study reveals that the just described interaction creates two fields that coexist within a molecule: one is a novel vectorial field formed via the interaction of the electric field with the Born-Huang non-adiabatic coupling terms (NACTs) and the other is an ordinary, scalar, electric field essentially identical to the original electric field. Section 4 devoted to the visualization of the outcomes via two intersecting Jahn-Teller cones which contain NACTs that become singular at the intersection point of these cones. Finally, the fact that eventually we are facing a kind of a cosmic situation may bring us to speculate that singular NACTs are a result of cosmic phenomena. Thus, if indeed this singularity is somehow connected to reality then, like other singularities in physics, it is formed at (or immediately after) the Big Bang and consequently, guarantees the formation of molecules.

Feasibility of observer system for determining orientation of balloon borne observational platforms

NASA Technical Reports Server (NTRS)

Nigro, N. J.; Gagliardi, J. C.

1982-01-01

An observer model for predicting the orientation of balloon borne research platforms was developed. The model was employed in conjunction with data from the LACATE mission in order to determine the platform orientation as a function of time.

Effects of monocortical and bicortical mini-implant anchorage on bone-borne palatal expansion using finite element analysis.

PubMed

Lee, Robert J; Moon, Won; Hong, Christine

2017-05-01

Bone-borne palatal expansion relies on mini-implant stability for successful orthopedic expansion. The large magnitude of applied force experienced by mini-implants during bone-borne expansion may lead to high failure rates. Use of bicortical mini-implant anchorage rather than monocortical anchorage may improve mini-implant stability. The aims of this study were to analyze and compare the effects of bicortical and monocortical anchorages on stress distribution and displacement during bone-borne palatal expansion using finite element analysis. Two skull models were constructed to represent expansion before and after midpalatal suture opening. Three clinical situations with varying mini-implant insertion depths were studied in each skull model: monocortical, 1-mm bicortical, and 2.5-mm bicortical. Finite element analysis simulations were performed for each clinical situation in both skull models. Von Mises stress distribution and transverse displacement were evaluated for all models. Peri-implant stress was greater in the monocortical anchorage model compared with both bicortical anchorage models. In addition, transverse displacement was greater and more parallel in the coronal plane for both bicortical models compared with the monocortical model. Minimal differences were observed between the 1-mm and the 2.5-mm bicortical models for both peri-implant stress and transverse displacement. Bicortical mini-implant anchorage results in improved mini-implant stability, decreased mini-implant deformation and fracture, more parallel expansion in the coronal plane, and increased expansion during bone-borne palatal expansion. However, the depth of bicortical mini-implant anchorage was not significant. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Effects of monocortical and bicortical mini-implant anchorage on bone-borne palatal expansion using finite element analysis

PubMed Central

Lee, Robert J.; Moon, Won; Hong, Christine

2017-01-01

Introduction Bone-borne palatal expansion relies on mini-implant stability for successful orthopedic expansion. The large magnitude of applied force experienced by mini-implants during bone-borne expansion may lead to high failure rates. Use of bicortical mini-implant anchorage rather than monocortical anchorage may improve mini-implant stability. The aim of this study was to analyze and compare the effects of bicortical and monocortical anchorage on stress distribution and displacement during bone-borne palatal expansion using finite element analysis (FEA). Methods Two skull models were constructed to represent expansion prior to and after midpalatal suture opening. Three clinical situations with varying mini-implant insertion depths were studied in each skull model: monocortical, 1mm bicortical, and 2.5mm bicortical. FEA simulations were performed for each clinical situation in both skull models. Von Mises stress distribution and transverse displacement was evaluated for all models. Results Peri-implant stress was greater in the monocortical anchorage model compared to both bicortical anchorage models. In addition, transverse displacement was greater and more parallel in the coronal plane for both bicortical models compared to the monocortical model. Minimal differences were observed between the 1mm bicortical and 2.5mm bicortical models for both peri-implant stress and transverse displacement. Conclusions Bicortical mini-implant anchorage results in improved mini-implant stability, decreased mini-implant deformation and fracture, more parallel expansion in the coronal plane, and increased expansion during bone-borne palatal expansion. However, the depth of bicortical mini-implant anchorage was not significant. PMID:28457266

Maxwell, James Clerk (1831-79)

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

Born in Edinburgh, Scotland, worked at Cambridge on electric and magnetic fields and their interrelation. Entered a prize-winning essay for a competition on the subject `The Motion of Saturn's Rings' and showed that the rings could be stable only if they consisted of numerous small solid particles in Keplerian motion with the inner edge moving faster than the outer edge. GEORGE AIRY, a compet...

Bezier Curves: A Classroom Investigation

ERIC Educational Resources Information Center

Staples, Ed

2005-01-01

Pierre Bezier was born on September 1 in Paris, 1910. Choosing the career path of his father, he gained electrical and mechanical engineering degrees by the time he was 21 years old. He began working for the car company Renault and stayed there for the next 42 years. In 1977 he received a doctorate in mathematics. Bezier, at the age of 50 began…

Lovell, Alfred Charles Bernard [Sir Bernard] (1913-)

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

Physicist and astronomer, born in Oldland Common, Gloucestershire, England. Worked on cosmic rays at Manchester, researched radar in the Second World War, and afterwards with J S HEY procured an ex-army mobile radar unit used to detect V-2 rockets and attempted to detect cosmic ray showers with it. Interference from the electric trams at Manchester displaced the work to the university's botanical...

Malfunction of medical equipment as a result of mains borne interference.

PubMed

Railton, R; Currie, G D; Corner, G A; Evans, A L

1993-08-01

Medical equipment has become more intelligent as the manufacturers have incorporated the latest microprocessor based technology. Equipment malfunction can be caused at any time by inherent errors in the control program but it is particularly important that this is designed to cope with the effects of electrical interference which, in addition, may cause corruption of the software. We have considered interference found in the mains supply in the hospital environment. Using a test protocol with appropriate interference simulators, a wide range of medical equipment was removed temporarily from use and its immunity to electrical mains borne interference tested. Battery operated mains rechargeable devices were unaffected by mains voltage variations including drop-outs and sags whereas mains powered devices were affected to varying degrees of severity. In particular, repetitive drop-outs caused loss of power due to fuse blowing in some life support equipment. Impulses affected 25% and pulse bursts 50% of the equipment tested with some evidence that the more recent designs coped better. The EEC Directive on electro-medical compatibility compliance may cause the design of equipment to be improved but hospitals will have to cope with the above problems in their existing equipment for many years to come.

A systematic review of mathematical models of mosquito-borne pathogen transmission: 1970–2010

PubMed Central

Reiner, Robert C.; Perkins, T. Alex; Barker, Christopher M.; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M.; George, Dylan B.; Le Menach, Arnaud; Pulliam, Juliet R. C.; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A. T.; Garcia, Andres J.; Gatton, Michelle L.; Gething, Peter W.; Hartley, David M.; Johnston, Geoffrey; Klein, Eili Y.; Michael, Edwin; Lindsay, Steven W.; Lloyd, Alun L.; Pigott, David M.; Reisen, William K.; Ruktanonchai, Nick; Singh, Brajendra K.; Tatem, Andrew J.; Kitron, Uriel; Hay, Simon I.; Scott, Thomas W.; Smith, David L.

2013-01-01

Mathematical models of mosquito-borne pathogen transmission originated in the early twentieth century to provide insights into how to most effectively combat malaria. The foundations of the Ross–Macdonald theory were established by 1970. Since then, there has been a growing interest in reducing the public health burden of mosquito-borne pathogens and an expanding use of models to guide their control. To assess how theory has changed to confront evolving public health challenges, we compiled a bibliography of 325 publications from 1970 through 2010 that included at least one mathematical model of mosquito-borne pathogen transmission and then used a 79-part questionnaire to classify each of 388 associated models according to its biological assumptions. As a composite measure to interpret the multidimensional results of our survey, we assigned a numerical value to each model that measured its similarity to 15 core assumptions of the Ross–Macdonald model. Although the analysis illustrated a growing acknowledgement of geographical, ecological and epidemiological complexities in modelling transmission, most models during the past 40 years closely resemble the Ross–Macdonald model. Modern theory would benefit from an expansion around the concepts of heterogeneous mosquito biting, poorly mixed mosquito-host encounters, spatial heterogeneity and temporal variation in the transmission process. PMID:23407571

Mitigating nonlinearity in full waveform inversion using scaled-Sobolev pre-conditioning

NASA Astrophysics Data System (ADS)

Zuberi, M. AH; Pratt, R. G.

2018-04-01

The Born approximation successfully linearizes seismic full waveform inversion if the background velocity is sufficiently accurate. When the background velocity is not known it can be estimated by using model scale separation methods. A frequently used technique is to separate the spatial scales of the model according to the scattering angles present in the data, by using either first- or second-order terms in the Born series. For example, the well-known `banana-donut' and the `rabbit ear' shaped kernels are, respectively, the first- and second-order Born terms in which at least one of the scattering events is associated with a large angle. Whichever term of the Born series is used, all such methods suffer from errors in the starting velocity model because all terms in the Born series assume that the background Green's function is known. An alternative approach to Born-based scale separation is to work in the model domain, for example, by Gaussian smoothing of the update vectors, or some other approach for separation by model wavenumbers. However such model domain methods are usually based on a strict separation in which only the low-wavenumber updates are retained. This implies that the scattered information in the data is not taken into account. This can lead to the inversion being trapped in a false (local) minimum when sharp features are updated incorrectly. In this study we propose a scaled-Sobolev pre-conditioning (SSP) of the updates to achieve a constrained scale separation in the model domain. The SSP is obtained by introducing a scaled Sobolev inner product (SSIP) into the measure of the gradient of the objective function with respect to the model parameters. This modified measure seeks reductions in the L2 norm of the spatial derivatives of the gradient without changing the objective function. The SSP does not rely on the Born prediction of scale based on scattering angles, and requires negligible extra computational cost per iteration. Synthetic examples from the Marmousi model show that the constrained scale separation using SSP is able to keep the background updates in the zone of attraction of the global minimum, in spite of using a poor starting model in which conventional methods fail.

Mathematics ability and related skills in preschoolers born very preterm.

PubMed

Hasler, Holly M; Akshoomoff, Natacha

2017-12-12

Children born very preterm (VPT) are at risk for academic, behavioral, and/or emotional problems. Mathematics is a particular weakness and better understanding of the relationship between preterm birth and early mathematics ability is needed, particularly as early as possible to aid in early intervention. Preschoolers born VPT (n = 58) and those born full term (FT; n = 29) were administered a large battery of measures within 6 months of beginning kindergarten. A multiple-mediation model was utilized to characterize the difference in skills underlying mathematics ability between groups. Children born VPT performed significantly worse than FT-born children on a measure of mathematics ability as well as full-scale IQ, verbal skills, visual-motor integration, phonological awareness, phonological working memory, motor skills, and executive functioning. Mathematics was significantly correlated with verbal skills, visual-motor integration, phonological processing, and motor skills across both groups. When entered into the mediation model, verbal skills, visual-motor integration, and phonological awareness were significant mediators of the group differences. This analysis provides insights into the pre-academic skills that are weak in preschoolers born VPT and their relationship to mathematics. It is important to identify children who will have difficulties as early as possible, particularly for VPT children who are at higher risk for academic difficulties. Therefore, this model may be used in evaluating VPT children for emerging difficulties as well as an indicator that if other weaknesses are found, an assessment of mathematics should be conducted.

The Healthy Immigrant (Migrant) Effect: In Search of a Better Native-Born Comparison Group*

PubMed Central

Hamilton, Tod G.

2016-01-01

This paper evaluates whether immigrants’ initial health advantage over their U.S.-born counterparts results primarily from characteristics correlated with their birth countries (e.g., immigrant culture) or from selective migration (e.g., unobserved characteristics such as motivation and ambition) by comparing recent immigrants’ health to that of recent U.S.-born interstate migrants (“U.S.-born movers”). Using data from the 1999–2013 waves of the March Current Population Survey, I find that, relative to U.S.-born adults (collectively), recent immigrants have a 6.1 percentage point lower probability of reporting their health as fair or poor. Changing the reference group to U.S.-born movers, however, reduces the recent immigrant health advantage by 28%. Similar reductions in the immigrant health advantage occurs in models estimated separately by either race/ethnicity or education level. Models that examine health differences between recent immigrants and U.S-born movers who both moved for a new job—a primary motivation behind moving for both immigrants and the U.S.-born—show that such immigrants have only a 1.9 percentage point lower probability of reporting their health as fair or poor. Together, the findings suggest that changing the reference group from U.S.-born adults collectively to U.S.-born movers reduces the identified immigrant health advantage, indicating that selective migration plays a significant role in explaining the initial health advantage of immigrants in the United States. PMID:26463553

Development of Multi-Layered Floating Floor for Cabin Noise Reduction

NASA Astrophysics Data System (ADS)

Song, Jee-Hun; Hong, Suk-Yoon; Kwon, Hyun-Wung

2017-12-01

Recently, regulations pertaining to the noise and vibration environment of ship cabins have been strengthened. In this paper, a numerical model is developed for multi-layered floating floor to predict the structure-borne noise in ship cabins. The theoretical model consists of multi-panel structures lined with high-density mineral wool. The predicted results for structure-borne noise when multi-layered floating floor is used are compared to the measure-ments made of a mock-up. A comparison of the predicted results and the experimental one shows that the developed model could be an effective tool for predicting structure-borne noise in ship cabins.

Web-based GIS: the vector-borne disease airline importation risk (VBD-AIR) tool

PubMed Central

2012-01-01

Background Over the past century, the size and complexity of the air travel network has increased dramatically. Nowadays, there are 29.6 million scheduled flights per year and around 2.7 billion passengers are transported annually. The rapid expansion of the network increasingly connects regions of endemic vector-borne disease with the rest of the world, resulting in challenges to health systems worldwide in terms of vector-borne pathogen importation and disease vector invasion events. Here we describe the development of a user-friendly Web-based GIS tool: the Vector-Borne Disease Airline Importation Risk Tool (VBD-AIR), to help better define the roles of airports and airlines in the transmission and spread of vector-borne diseases. Methods Spatial datasets on modeled global disease and vector distributions, as well as climatic and air network traffic data were assembled. These were combined to derive relative risk metrics via air travel for imported infections, imported vectors and onward transmission, and incorporated into a three-tier server architecture in a Model-View-Controller framework with distributed GIS components. A user-friendly web-portal was built that enables dynamic querying of the spatial databases to provide relevant information. Results The VBD-AIR tool constructed enables the user to explore the interrelationships among modeled global distributions of vector-borne infectious diseases (malaria. dengue, yellow fever and chikungunya) and international air service routes to quantify seasonally changing risks of vector and vector-borne disease importation and spread by air travel, forming an evidence base to help plan mitigation strategies. The VBD-AIR tool is available at http://www.vbd-air.com. Conclusions VBD-AIR supports a data flow that generates analytical results from disparate but complementary datasets into an organized cartographical presentation on a web map for the assessment of vector-borne disease movements on the air travel network. The framework built provides a flexible and robust informatics infrastructure by separating the modules of functionality through an ontological model for vector-borne disease. The VBD‒AIR tool is designed as an evidence base for visualizing the risks of vector-borne disease by air travel for a wide range of users, including planners and decisions makers based in state and local government, and in particular, those at international and domestic airports tasked with planning for health risks and allocating limited resources. PMID:22892045

Web-based GIS: the vector-borne disease airline importation risk (VBD-AIR) tool.

PubMed

Huang, Zhuojie; Das, Anirrudha; Qiu, Youliang; Tatem, Andrew J

2012-08-14

Over the past century, the size and complexity of the air travel network has increased dramatically. Nowadays, there are 29.6 million scheduled flights per year and around 2.7 billion passengers are transported annually. The rapid expansion of the network increasingly connects regions of endemic vector-borne disease with the rest of the world, resulting in challenges to health systems worldwide in terms of vector-borne pathogen importation and disease vector invasion events. Here we describe the development of a user-friendly Web-based GIS tool: the Vector-Borne Disease Airline Importation Risk Tool (VBD-AIR), to help better define the roles of airports and airlines in the transmission and spread of vector-borne diseases. Spatial datasets on modeled global disease and vector distributions, as well as climatic and air network traffic data were assembled. These were combined to derive relative risk metrics via air travel for imported infections, imported vectors and onward transmission, and incorporated into a three-tier server architecture in a Model-View-Controller framework with distributed GIS components. A user-friendly web-portal was built that enables dynamic querying of the spatial databases to provide relevant information. The VBD-AIR tool constructed enables the user to explore the interrelationships among modeled global distributions of vector-borne infectious diseases (malaria. dengue, yellow fever and chikungunya) and international air service routes to quantify seasonally changing risks of vector and vector-borne disease importation and spread by air travel, forming an evidence base to help plan mitigation strategies. The VBD-AIR tool is available at http://www.vbd-air.com. VBD-AIR supports a data flow that generates analytical results from disparate but complementary datasets into an organized cartographical presentation on a web map for the assessment of vector-borne disease movements on the air travel network. The framework built provides a flexible and robust informatics infrastructure by separating the modules of functionality through an ontological model for vector-borne disease. The VBD‒AIR tool is designed as an evidence base for visualizing the risks of vector-borne disease by air travel for a wide range of users, including planners and decisions makers based in state and local government, and in particular, those at international and domestic airports tasked with planning for health risks and allocating limited resources.

Invasion of two tick-borne diseases across New England: harnessing human surveillance data to capture underlying ecological invasion processes

PubMed Central

Walter, Katharine S.; Pepin, Kim M.; Webb, Colleen T.; Gaff, Holly D.; Krause, Peter J.; Pitzer, Virginia E.; Diuk-Wasser, Maria A.

2016-01-01

Modelling the spatial spread of vector-borne zoonotic pathogens maintained in enzootic transmission cycles remains a major challenge. The best available spatio-temporal data on pathogen spread often take the form of human disease surveillance data. By applying a classic ecological approach—occupancy modelling—to an epidemiological question of disease spread, we used surveillance data to examine the latent ecological invasion of tick-borne pathogens. Over the last half-century, previously undescribed tick-borne pathogens including the agents of Lyme disease and human babesiosis have rapidly spread across the northeast United States. Despite their epidemiological importance, the mechanisms of tick-borne pathogen invasion and drivers underlying the distinct invasion trajectories of the co-vectored pathogens remain unresolved. Our approach allowed us to estimate the unobserved ecological processes underlying pathogen spread while accounting for imperfect detection of human cases. Our model predicts that tick-borne diseases spread in a diffusion-like manner with occasional long-distance dispersal and that babesiosis spread exhibits strong dependence on Lyme disease. PMID:27252022

Design and qualification of the interferometer for the GOSAT-2 spectrometer

NASA Astrophysics Data System (ADS)

Montembault, Yan; Moreau, Louis; Roux, Michel; Buijs, Henry; Soucy, Marc-André

2016-10-01

GOSAT-2 is the successor of the Greenhouse gases Observing SATellite (GOSAT, "IBUKI") launched in 2009 by Japan Aerospace Exploration Agency (JAXA). GOSAT-2 will continue and enhance space borne measurements of greenhouse gases started by GOSAT and monitor the impacts of climate change and human activities on the carbon cycle. It will also contribute to climate science and climate change related policies. The GOSAT-2 spacecraft will carry two earth observation instruments: FTS-2, the second generation of the TANSO-FTS and CAI-2, a Cloud and Aerosol Imager. Mitsubishi Electric Corporation is the prime contractor of GOSAT-2. Harris is the subcontractor of the spectrometer. ABB, who successfully designed, manufactured, and delivered the interferometer for the TANSO-FTS instrument for GOSAT, is currently delivering the modulator for the FTS-2 instrument to Mitsubishi Electric Corporation. Built on the TANSO-FTS heritage, FTS-2 is a thermal and near infrared sensor for carbon observation based on a Fourier transform spectrometer featuring larger optical throughput than TANSO-FTS. This paper presents an overview of the design of the FTS-2 interferometer as well as key qualification and performance verification activities conducted on the interferometer flight model.

The evaluation of a shuttle borne lidar experiment to measure the global distribution of aerosols and their effect on the atmospheric heat budget

NASA Technical Reports Server (NTRS)

Shipley, S. T.; Joseph, J. H.; Trauger, J. T.; Guetter, P. J.; Eloranta, E. W.; Lawler, J. E.; Wiscombe, W. J.; Odell, A. P.; Roesler, F. L.; Weinman, J. A.

1975-01-01

A shuttle-borne lidar system is described, which will provide basic data about aerosol distributions for developing climatological models. Topics discussed include: (1) present knowledge of the physical characteristics of desert aerosols and the absorption characteristics of atmospheric gas, (2) radiative heating computations, and (3) general circulation models. The characteristics of a shuttle-borne radar are presented along with some laboratory studies which identify schemes that permit the implementation of a high spectral resolution lidar system.

Mothers, Fathers, Peers, and Mexican-Origin Adolescents’ Sexual Intentions

PubMed Central

Killoren, Sarah E.; Updegraff, Kimberly A.; Christopher, F. Scott; Umaña-Taylor, Adriana J.

2011-01-01

Drawing on a symbolic-interaction perspective and a compensation model, the processes linking mother-and father-adolescent relationship qualities, deviant peer affiliations, and adolescents’ sexual intentions were investigated for 246 Mexican-origin youths born in the United States and in Mexico using multiple-group structural equation models. Deviant peer affiliations significantly mediated the relations between paternal acceptance and sexual intentions and between disclosure to mothers and sexual intentions for U.S.-born youths but not for Mexico-born youths. Findings highlight the importance of examining variability as a function of youth nativity. PMID:21278903

Effect of wind gusts on the motion of a balloon-borne observation platform

NASA Technical Reports Server (NTRS)

Nigro, N. J.; Johanek, F. M.

1982-01-01

The effect of wind gusts on the magnitude of the pendulation angles of a balloon-borne observation platform is determined. A system mathematical model is developed and the solution of this model is used to determine the magnitude of the observation platforms pendulation angles.

Big Bang Day: 5 Particles - 1. The Electron

ScienceCinema

None

2017-12-09

Simon Singh looks at the stories behind the discovery of 5 of the universe's most significant subatomic particles: the Electron, the Quark, the Anti-particle, the Neutrino and the "next particle". 1. The Electron Just over a century ago, British physicist J.J. Thompson experimenting with electric currents and charged particles inside empty glass tubes, showed that atoms are divisible into indivisible elementary particles. But how could atoms be built up of these so called "corpuscles"? An exciting 30 year race ensued, to grasp the planetary model of the atom with its orbiting electrons, and the view inside the atom was born. Whilst the number of electrons around the nucleus of an atom determines their the chemistry of all elements, the power of electrons themselves have been harnessed for everyday use: electron beams for welding,cathode ray tubes and radiation therapy.

Running reorganizes the circuitry of one-week-old adult-born hippocampal neurons.

PubMed

Sah, Nirnath; Peterson, Benjamin D; Lubejko, Susan T; Vivar, Carmen; van Praag, Henriette

2017-09-07

Adult hippocampal neurogenesis is an important form of structural and functional plasticity in the mature mammalian brain. The existing consensus is that GABA regulates the initial integration of adult-born neurons, similar to neuronal development during embryogenesis. Surprisingly, virus-based anatomical tracing revealed that very young, one-week-old, new granule cells in male C57Bl/6 mice receive input not only from GABAergic interneurons, but also from multiple glutamatergic cell types, including mature dentate granule cells, area CA1-3 pyramidal cells and mossy cells. Consistently, patch-clamp recordings from retrovirally labeled new granule cells at 7-8 days post retroviral injection (dpi) show that these cells respond to NMDA application with tonic currents, and that both electrical and optogenetic stimulation can evoke NMDA-mediated synaptic responses. Furthermore, new dentate granule cell number, morphology and excitatory synaptic inputs at 7 dpi are modified by voluntary wheel running. Overall, glutamatergic and GABAergic innervation of newly born neurons in the adult hippocampus develops concurrently, and excitatory input is reorganized by exercise.

Elastic scattering of spin-polarized electrons and positrons from 23Na nuclei

NASA Astrophysics Data System (ADS)

Jakubassa-Amundsen, D. H.

2018-07-01

Differential cross sections and polarization correlations for the scattering of relativistic spin-polarized leptons from unpolarized ground-state sodium nuclei are calculated within the distorted-wave Born approximation (DWBA). Various nuclear ground-state charge distributions are probed. Besides potential scattering, also electric C2 and magnetic M1 and M3 transitions are taken into account. It is shown that even for a light nucleus such as 23Na there are considerable electron-positron differences at high collision energies and large scattering angles. In particular, the symmetry of the Sherman function with respect to a global sign change, as predicted by the second-order Born approximation when replacing electrons by positrons, is broken whenever the diffraction structures come into play beyond 100 MeV.

BRNBOX v.1.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aldridge, David F.

Program BRNBOX conducts a systematic search through a pre-defined 3D volume of candidate sub-surface Born scattering points in order to identify the particular point that minimizes the misfit between predicted (i.e., calculated) and observed electromagnetic (EM) data. This global minimum misfit point is interpreted as the location where electrically conductive proppant is injected into a sub-surface petroleum reservoir in a hydraulic fracturing experiment.

Practical solutions to implementing "Born Semantic" data systems

NASA Astrophysics Data System (ADS)

Leadbetter, A.; Buck, J. J. H.; Stacey, P.

2015-12-01

The concept of data being "Born Semantic" has been proposed in recent years as a Semantic Web analogue to the idea of data being "born digital"[1], [2]. Within the "Born Semantic" concept, data are captured digitally and at a point close to the time of creation are annotated with markup terms from semantic web resources (controlled vocabularies, thesauri or ontologies). This allows heterogeneous data to be more easily ingested and amalgamated in near real-time due to the standards compliant annotation of the data. In taking the "Born Semantic" proposal from concept to operation, a number of difficulties have been encountered. For example, although there are recognised methods such as Header, Dictionary, Triples [3] for the compression, publication and dissemination of large volumes of triples these systems are not practical to deploy in the field on low-powered (both electrically and computationally) devices. Similarly, it is not practical for instruments to output fully formed semantically annotated data files if they are designed to be plugged into a modular system and the data to be centrally logged in the field as is the case on Argo floats and oceanographic gliders where internal bandwidth becomes an issue [2]. In light of these issues, this presentation will concentrate on pragmatic solutions being developed to the problem of generating Linked Data in near real-time systems. Specific examples from the European Commission SenseOCEAN project where Linked Data systems are being developed for autonomous underwater platforms, and from work being undertaken in the streaming of data from the Irish Galway Bay Cable Observatory initiative will be highlighted. Further, developments of a set of tools for the LogStash-ElasticSearch software ecosystem to allow the storing and retrieval of Linked Data will be introduced. References[1] A. Leadbetter & J. Fredericks, We have "born digital" - now what about "born semantic"?, European Geophysical Union General Assembly, 2014.[2] J. Buck & A. Leadbetter, Born semantic: linking data from sensors to users and balancing hardware limitations with data standards, European Geophysical Union General Assembly, 2015.[3] J. Fernandez et al., Binary RDF Representation for Publication and Exchange (HDT), Web Semantics 19:22-41, 2013.

Medical electricity and madness in the 18th century: the legacies of Benjamin Franklin and Jan Ingenhousz.

PubMed

Beaudreau, Sherry Ann; Finger, Stanley

2006-01-01

Benjamin Franklin had at least two accidents that resulted in electricity passing through his brain. In addition, he witnessed a patient's similar accident and performed an experiment that showed how humans could endure shocks to the head without serious ill effects, other than amnesia. Jan Ingenhousz, Franklin's Dutch-born medical correspondent better known for his discovery of photosynthesis, also had a serious accident that sent electricity though his head and, in a letter to Franklin, he described how he felt unusually elated the next day. During the 1780s, Franklin and Ingenhousz encouraged leading French and English electrical "operators" to try shocking the heads of melancholic and other deranged patients in their wards. Although they did not state that they were responding to Ingenhousz's and Franklin's suggestions, Birch, Aldini, and Gale soon did precisely what Ingenhousz and Franklin had suggested. These practitioners did not appear to induce convulsions in their mentally ill patients, but they still reported notable successes.

Socially optimal electric driving range of plug-in hybrid electric vehicles

DOE PAGES

Kontou, Eleftheria; Yin, Yafeng; Lin, Zhenhong

2015-07-25

Our study determines the optimal electric driving range of plug-in hybrid electric vehicles (PHEVs) that minimizes the daily cost borne by the society when using this technology. An optimization framework is developed and applied to datasets representing the US market. Results indicate that the optimal range is 16 miles with an average social cost of 3.19 per day when exclusively charging at home, compared to 3.27 per day of driving a conventional vehicle. The optimal range is found to be sensitive to the cost of battery packs and the price of gasoline. Moreover, when workplace charging is available, the optimalmore » electric driving range surprisingly increases from 16 to 22 miles, as larger batteries would allow drivers to better take advantage of the charging opportunities to achieve longer electrified travel distances, yielding social cost savings. If workplace charging is available, the optimal density is to deploy a workplace charger for every 3.66 vehicles. Finally, the diversification of the battery size, i.e., introducing a pair and triple of electric driving ranges to the market, could further decrease the average societal cost per PHEV by 7.45% and 11.5% respectively.« less

Dr. Alexander Garden, a Linnaean in colonial America, and the saga of five "electric eels".

PubMed

Finger, Stanley

2010-01-01

Alexander Garden (1730-1791) was born in Scotland, where he trained in medicine before settling in South Carolina in 1752. With a passion for collecting and a love of nature, he sent specimens to Linnaeus and his associates in Europe. In 1774, Garden observed and conducted electrical experiments on some "eels" that had survived the trip from Surinam to Charleston. His detailed observations and reasons for believing they emit electricity were read before the Royal Society of London and subsequently published. He also advised the sea captain who owned the eels on how to preserve them and where to deliver their bodies if they died en route to London. Although they did die en route, John Hunter of the Royal Society was able to provide excellent descriptions of their electric organs because they were so well preserved. The sequence of events that followed led to other live eels surviving the voyage to London, where they were observed to spark in darkness in 1776. This was a critical piece of evidence in favor of fish electricity and eventually for the more revolutionary idea that even human nerves and muscles might function electrically.

Primordial cosmology in mimetic born-infeld gravity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bouhmadi-Lopez, Mariam; Chen, Che -Yu; Chen, Pisin

Here, the Eddington-inspired-Born-Infeld (EiBI) model is reformulated within the mimetic approach. In the presence of a mimetic field, the model contains non-trivial vacuum solutions which could be free of spacetime singularity because of the Born-Infeld nature of the theory. We study a realistic primordial vacuum universe and prove the existence of regular solutions, such as primordial inflationary solutions of de Sitter type or bouncing solutions. Besides, the linear instabilities present in the EiBI model are found to be avoidable for some interesting bouncing solutions in which the physical metric as well as the auxiliary metric are regular at the backgroundmore » level.« less

Primordial cosmology in mimetic born-infeld gravity

DOE PAGES

Bouhmadi-Lopez, Mariam; Chen, Che -Yu; Chen, Pisin

2017-11-29

Here, the Eddington-inspired-Born-Infeld (EiBI) model is reformulated within the mimetic approach. In the presence of a mimetic field, the model contains non-trivial vacuum solutions which could be free of spacetime singularity because of the Born-Infeld nature of the theory. We study a realistic primordial vacuum universe and prove the existence of regular solutions, such as primordial inflationary solutions of de Sitter type or bouncing solutions. Besides, the linear instabilities present in the EiBI model are found to be avoidable for some interesting bouncing solutions in which the physical metric as well as the auxiliary metric are regular at the backgroundmore » level.« less

A comparative analysis of three vector-borne diseases across Australia using seasonal and meteorological models

PubMed Central

Stratton, Margaret D.; Ehrlich, Hanna Y.; Mor, Siobhan M.; Naumova, Elena N.

2017-01-01

Ross River virus (RRV), Barmah Forest virus (BFV), and dengue are three common mosquito-borne diseases in Australia that display notable seasonal patterns. Although all three diseases have been modeled on localized scales, no previous study has used harmonic models to compare seasonality of mosquito-borne diseases on a continent-wide scale. We fit Poisson harmonic regression models to surveillance data on RRV, BFV, and dengue (from 1993, 1995 and 1991, respectively, through 2015) incorporating seasonal, trend, and climate (temperature and rainfall) parameters. The models captured an average of 50–65% variability of the data. Disease incidence for all three diseases generally peaked in January or February, but peak timing was most variable for dengue. The most significant predictor parameters were trend and inter-annual periodicity for BFV, intra-annual periodicity for RRV, and trend for dengue. We found that a Temperature Suitability Index (TSI), designed to reclassify climate data relative to optimal conditions for vector establishment, could be applied to this context. Finally, we extrapolated our models to estimate the impact of a false-positive BFV epidemic in 2013. Creating these models and comparing variations in periodicities may provide insight into historical outbreaks as well as future patterns of mosquito-borne diseases. PMID:28071683

A comparative analysis of three vector-borne diseases across Australia using seasonal and meteorological models.

PubMed

Stratton, Margaret D; Ehrlich, Hanna Y; Mor, Siobhan M; Naumova, Elena N

2017-01-10

Ross River virus (RRV), Barmah Forest virus (BFV), and dengue are three common mosquito-borne diseases in Australia that display notable seasonal patterns. Although all three diseases have been modeled on localized scales, no previous study has used harmonic models to compare seasonality of mosquito-borne diseases on a continent-wide scale. We fit Poisson harmonic regression models to surveillance data on RRV, BFV, and dengue (from 1993, 1995 and 1991, respectively, through 2015) incorporating seasonal, trend, and climate (temperature and rainfall) parameters. The models captured an average of 50-65% variability of the data. Disease incidence for all three diseases generally peaked in January or February, but peak timing was most variable for dengue. The most significant predictor parameters were trend and inter-annual periodicity for BFV, intra-annual periodicity for RRV, and trend for dengue. We found that a Temperature Suitability Index (TSI), designed to reclassify climate data relative to optimal conditions for vector establishment, could be applied to this context. Finally, we extrapolated our models to estimate the impact of a false-positive BFV epidemic in 2013. Creating these models and comparing variations in periodicities may provide insight into historical outbreaks as well as future patterns of mosquito-borne diseases.

A comparative analysis of three vector-borne diseases across Australia using seasonal and meteorological models

NASA Astrophysics Data System (ADS)

Stratton, Margaret D.; Ehrlich, Hanna Y.; Mor, Siobhan M.; Naumova, Elena N.

2017-01-01

Ross River virus (RRV), Barmah Forest virus (BFV), and dengue are three common mosquito-borne diseases in Australia that display notable seasonal patterns. Although all three diseases have been modeled on localized scales, no previous study has used harmonic models to compare seasonality of mosquito-borne diseases on a continent-wide scale. We fit Poisson harmonic regression models to surveillance data on RRV, BFV, and dengue (from 1993, 1995 and 1991, respectively, through 2015) incorporating seasonal, trend, and climate (temperature and rainfall) parameters. The models captured an average of 50-65% variability of the data. Disease incidence for all three diseases generally peaked in January or February, but peak timing was most variable for dengue. The most significant predictor parameters were trend and inter-annual periodicity for BFV, intra-annual periodicity for RRV, and trend for dengue. We found that a Temperature Suitability Index (TSI), designed to reclassify climate data relative to optimal conditions for vector establishment, could be applied to this context. Finally, we extrapolated our models to estimate the impact of a false-positive BFV epidemic in 2013. Creating these models and comparing variations in periodicities may provide insight into historical outbreaks as well as future patterns of mosquito-borne diseases.

Prostate cancer screening behavior in men from seven ethnic groups: the fear factor.

PubMed

Consedine, Nathan S; Morgenstern, Amy H; Kudadjie-Gyamfi, Elizabeth; Magai, Carol; Neugut, Alfred I

2006-02-01

Rates of prostate cancer screening are known to vary among the major ethnic groups. However, likely variations in screening behavior among ethnic subpopulations and the likely role of psychological characteristics remain understudied. We examined differences in prostate cancer screening among samples of 44 men from each of seven ethnic groups (N = 308; U.S.-born European Americans, U.S.-born African Americans, men from the English-speaking Caribbean, Haitians, Dominicans, Puerto Ricans, and Eastern Europeans) and the associations among trait fear, emotion regulatory characteristics, and screening. As expected, there were differences in the frequency of both digital rectal exam (DRE) and prostate-specific antigen (PSA) tests among the groups, even when demographic factors and access were controlled. Haitian men reported fewer DRE and PSA tests than either U.S.-born European American or Dominican men, and immigrant Eastern European men reported fewer tests than U.S.-born European Americans; consistent with prior research, U.S.-born African Americans differed from U.S.-born European Americans for DRE but not PSA frequency. Second, the addition of trait fear significantly improved model fit, as did the inclusion of a quadratic, inverted U, trait fear term, even where demographics, access, and ethnicity were controlled. Trait fear did not interact with ethnicity, suggesting its effect may operate equally across groups, and adding patterns of information processing and emotion regulation to the model did not improve model fit. Overall, our data suggest that fear is among the key psychological determinants of male screening behavior and would be usefully considered in models designed to increase male screening frequency.

Generalized Born Models of Macromolecular Solvation Effects

NASA Astrophysics Data System (ADS)

Bashford, Donald; Case, David A.

2000-10-01

It would often be useful in computer simulations to use a simple description of solvation effects, instead of explicitly representing the individual solvent molecules. Continuum dielectric models often work well in describing the thermodynamic aspects of aqueous solvation, and approximations to such models that avoid the need to solve the Poisson equation are attractive because of their computational efficiency. Here we give an overview of one such approximation, the generalized Born model, which is simple and fast enough to be used for molecular dynamics simulations of proteins and nucleic acids. We discuss its strengths and weaknesses, both for its fidelity to the underlying continuum model and for its ability to replace explicit consideration of solvent molecules in macromolecular simulations. We focus particularly on versions of the generalized Born model that have a pair-wise analytical form, and therefore fit most naturally into conventional molecular mechanics calculations.

Time-dependent calculations of transfer ionization by fast proton-helium collision in one-dimensional kinematics

NASA Astrophysics Data System (ADS)

Serov, Vladislav V.; Kheifets, A. S.

2014-12-01

We analyze a transfer ionization (TI) reaction in the fast proton-helium collision H++He →H0+He2 ++ e- by solving a time-dependent Schrödinger equation (TDSE) under the classical projectile motion approximation in one-dimensional kinematics. In addition, we construct various time-independent analogs of our model using lowest-order perturbation theory in the form of the Born series. By comparing various aspects of the TDSE and the Born series calculations, we conclude that the recent discrepancies of experimental and theoretical data may be attributed to deficiency of the Born models used by other authors. We demonstrate that the correct Born series for TI should include the momentum-space overlap between the double-ionization amplitude and the wave function of the transferred electron.

Pathways linking racial/ethnic discrimination and sleep among U.S.-born and foreign-born Latinxs.

PubMed

Garcini, Luz M; Chirinos, Diana A; Murdock, Kyle W; Seiler, Annina; LeRoy, Angie S; Peek, Kristen; Cutchin, Malcom P; Fagundes, Christopher

2018-06-01

This study examined the association between racial/ethnic discrimination and sleep through psychological distress and body mass index (BMI), and determined whether the aforementioned associations vary between U.S. and foreign-born Latinxs. Participants were 1332 Latinx adults enrolled in the Texas City Stress and Health Study. Multistage sampling methods were used to select participants. A model linking racial/ethnic discrimination with sleep disturbances through direct and indirect (i.e., psychological distress and BMI) paths demonstrated good fit. Greater racial/ethnic discrimination was associated with greater psychological distress and higher BMI. Psychological distress and BMI were also significant predictors of sleep disturbances. The indirect path from racial/ethnic discrimination to sleep disturbances via psychological distress was significant. A model with parameters constrained to be equal between U.S.-born and foreign-born Latinxs suggested associations were comparable between these groups. Our study demonstrated the relevance of racial/ethnic discrimination to sleep disturbances, particularly its association via psychological distress among Latinxs.

Acculturation Models of Immigrant Soviet Adolescents in Israel

ERIC Educational Resources Information Center

Shamai, Shmuel; Ilatov, Zinaida

2005-01-01

This study probed acculturation in Israel of immigrant students from the former USSR from the perception of the host society and the students. The finding from a questionnaire distributed to Israeli-born and immigrant students indicated that most but not all of the Israel-born students applied an assimilatory model while the immigrants were split…

Seven challenges for modelling indirect transmission: Vector-borne diseases, macroparasites and neglected tropical diseases

PubMed Central

Hollingsworth, T. Déirdre; Pulliam, Juliet R.C.; Funk, Sebastian; Truscott, James E.; Isham, Valerie; Lloyd, Alun L.

2015-01-01

Many of the challenges which face modellers of directly transmitted pathogens also arise when modelling the epidemiology of pathogens with indirect transmission – whether through environmental stages, vectors, intermediate hosts or multiple hosts. In particular, understanding the roles of different hosts, how to measure contact and infection patterns, heterogeneities in contact rates, and the dynamics close to elimination are all relevant challenges, regardless of the mode of transmission. However, there remain a number of challenges that are specific and unique to modelling vector-borne diseases and macroparasites. Moreover, many of the neglected tropical diseases which are currently targeted for control and elimination are vector-borne, macroparasitic, or both, and so this article includes challenges which will assist in accelerating the control of these high-burden diseases. Here, we discuss the challenges of indirect measures of infection in humans, whether through vectors or transmission life stages and in estimating the contribution of different host groups to transmission. We also discuss the issues of “evolution-proof” interventions against vector-borne disease. PMID:25843376

Engine isolation for structural-borne interior noise reduction in a general aviation aircraft

NASA Technical Reports Server (NTRS)

Unruh, J. F.; Scheidt, D. C.

1981-01-01

Engine vibration isolation for structural-borne interior noise reduction is investigated. A laboratory based test procedure to simulate engine induced structure-borne noise transmission, the testing of a range of candidate isolators for relative performance data, and the development of an analytical model of the transmission phenomena for isolator design evaluation are addressed. The isolator relative performance test data show that the elastomeric isolators do not appear to operate as single degree of freedom systems with respect to noise isolation. Noise isolation beyond 150 Hz levels off and begins to decrease somewhat above 600 Hz. Coupled analytical and empirical models were used to study the structure-borne noise transmission phenomena. Correlation of predicted results with measured data show that (1) the modeling procedures are reasonably accurate for isolator design evaluation, (2) the frequency dependent properties of the isolators must be included in the model if reasonably accurate noise prediction beyond 150 Hz is desired. The experimental and analytical studies were carried out in the frequency range from 10 Hz to 1000 Hz.

Seven challenges for modelling indirect transmission: vector-borne diseases, macroparasites and neglected tropical diseases.

PubMed

Hollingsworth, T Déirdre; Pulliam, Juliet R C; Funk, Sebastian; Truscott, James E; Isham, Valerie; Lloyd, Alun L

2015-03-01

Many of the challenges which face modellers of directly transmitted pathogens also arise when modelling the epidemiology of pathogens with indirect transmission--whether through environmental stages, vectors, intermediate hosts or multiple hosts. In particular, understanding the roles of different hosts, how to measure contact and infection patterns, heterogeneities in contact rates, and the dynamics close to elimination are all relevant challenges, regardless of the mode of transmission. However, there remain a number of challenges that are specific and unique to modelling vector-borne diseases and macroparasites. Moreover, many of the neglected tropical diseases which are currently targeted for control and elimination are vector-borne, macroparasitic, or both, and so this article includes challenges which will assist in accelerating the control of these high-burden diseases. Here, we discuss the challenges of indirect measures of infection in humans, whether through vectors or transmission life stages and in estimating the contribution of different host groups to transmission. We also discuss the issues of "evolution-proof" interventions against vector-borne disease. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Cultural implications of differing rates of medically indicated and elective cesarean deliveries for foreign-born versus native-born taiwanese mothers.

PubMed

Huang, Chun-Che; Li, Chung-Yi; Yang, Chiang-Hsing

2012-07-01

The study aimed to assess the number of medically indicated and elective cesarean deliveries among foreign-born and native-born mothers in Taiwan. National Health Insurance (NHI) inpatient datasets in Taiwan between 2001 and 2003 showed 673,830 singleton deliveries, of which 66,687 were to foreign-born mothers and 607,143 were to Taiwan-born mothers. Univariate and multivariate logistic regression models were used to estimate the likelihood of using inpatient services for medically indicated and elective cesarean delivery. During the study period, foreign-born mothers were significantly less likely to undergo medically indicated (odds ratio [OR], 0.82; 95% confidence interval (95% CI), 0.79-0.85) and elective (OR, 0.50; 95% CI, 0.47-0.53) cesarean delivery than Taiwan-born mothers after adjusting for clinical and nonclinical factors. Foreign-born mothers aged 18-50 years are less likely to undergo medically indicated and elective cesarean delivery under Taiwan's NHI coverage. As the birth rate for immigrant women increases, cross-cultural maternity care during pregnancy and childbirth for immigrant mothers needs to be addressed.

Processing Satellite Data for Slant Total Electron Content Measurements

NASA Technical Reports Server (NTRS)

Stephens, Philip John (Inventor); Komjathy, Attila (Inventor); Wilson, Brian D. (Inventor); Mannucci, Anthony J. (Inventor)

2016-01-01

A method, system, and apparatus provide the ability to estimate ionospheric observables using space-borne observations. Space-borne global positioning system (GPS) data of ionospheric delay are obtained from a satellite. The space-borne GPS data are combined with ground-based GPS observations. The combination is utilized in a model to estimate a global three-dimensional (3D) electron density field.

A molecular Debye-Huckel theory of solvation in polar fluids: An extension of the Born model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Tiejun; Song, Xueyu

A dielectric response theory of solvation beyond the conventional Born model for polar fluids is presented. The dielectric response of a polar fluid is described by a Born response mode and a linear combination of Debye-Hückel-like response modes that capture the nonlocal response of polar fluids. The Born mode is characterized by a bulk dielectric constant, while a Debye-Hückel mode is characterized by its corresponding Debye screening length. Both the bulk dielectric constant and the Debye screening lengths are determined from the bulk dielectric function of the polar fluid. The linear combination coefficients of the response modes are evaluated inmore » a self-consistent way and can be used to evaluate the electrostatic contribution to the thermodynamic properties of a polar fluid. In conclusion, our theory is applied to a dipolar hard sphere fluid as well as interaction site models of polar fluids such as water, where the electrostatic contribution to their thermodynamic properties can be obtained accurately.« less

A molecular Debye-Huckel theory of solvation in polar fluids: An extension of the Born model

DOE PAGES

Xiao, Tiejun; Song, Xueyu

2017-12-06

A dielectric response theory of solvation beyond the conventional Born model for polar fluids is presented. The dielectric response of a polar fluid is described by a Born response mode and a linear combination of Debye-Hückel-like response modes that capture the nonlocal response of polar fluids. The Born mode is characterized by a bulk dielectric constant, while a Debye-Hückel mode is characterized by its corresponding Debye screening length. Both the bulk dielectric constant and the Debye screening lengths are determined from the bulk dielectric function of the polar fluid. The linear combination coefficients of the response modes are evaluated inmore » a self-consistent way and can be used to evaluate the electrostatic contribution to the thermodynamic properties of a polar fluid. In conclusion, our theory is applied to a dipolar hard sphere fluid as well as interaction site models of polar fluids such as water, where the electrostatic contribution to their thermodynamic properties can be obtained accurately.« less

Functional Limitations and Nativity Status among Older Arab, Asian, Black, Hispanic, and White Americans

PubMed Central

Dallo, Florence J.; Booza, Jason; Nguyen, Norma D.

2013-01-01

Background To examine the association between nativity status (foreign and US-born) by race/ethnicity (Arab, Asian, black, Hispanic, white) on having a functional limitation. Methods We used American Community Survey data (2001-2007; n=1,964,777; 65+ years) and estimated odds ratios (95% confidence intervals). Results In the crude model, foreign-born Blacks, Hispanics and Arabs were more likely, while Asians were less likely to report having a functional limitation compared to white. In the fully adjusted model, Blacks, Hispanics, and Asians were less likely, while Arabs were more likely to report having a functional limitation. In both the crude and fully adjusted models, US-born Blacks and Hispanics were more likely, while Asians and Arabs were less likely to report having a functional limitation compared to whites. Discussion Policies and programs tailored to foreign-born Arab Americans may help prevent or delay the onset of disability, especially when initiated shortly after their arrival to the US. PMID:24165988

A molecular Debye-Hückel theory of solvation in polar fluids: An extension of the Born model

NASA Astrophysics Data System (ADS)

Xiao, Tiejun; Song, Xueyu

2017-12-01

A dielectric response theory of solvation beyond the conventional Born model for polar fluids is presented. The dielectric response of a polar fluid is described by a Born response mode and a linear combination of Debye-Hückel-like response modes that capture the nonlocal response of polar fluids. The Born mode is characterized by a bulk dielectric constant, while a Debye-Hückel mode is characterized by its corresponding Debye screening length. Both the bulk dielectric constant and the Debye screening lengths are determined from the bulk dielectric function of the polar fluid. The linear combination coefficients of the response modes are evaluated in a self-consistent way and can be used to evaluate the electrostatic contribution to the thermodynamic properties of a polar fluid. Our theory is applied to a dipolar hard sphere fluid as well as interaction site models of polar fluids such as water, where the electrostatic contribution to their thermodynamic properties can be obtained accurately.

A molecular Debye-Hückel theory of solvation in polar fluids: An extension of the Born model.

PubMed

Xiao, Tiejun; Song, Xueyu

2017-12-07

A dielectric response theory of solvation beyond the conventional Born model for polar fluids is presented. The dielectric response of a polar fluid is described by a Born response mode and a linear combination of Debye-Hückel-like response modes that capture the nonlocal response of polar fluids. The Born mode is characterized by a bulk dielectric constant, while a Debye-Hückel mode is characterized by its corresponding Debye screening length. Both the bulk dielectric constant and the Debye screening lengths are determined from the bulk dielectric function of the polar fluid. The linear combination coefficients of the response modes are evaluated in a self-consistent way and can be used to evaluate the electrostatic contribution to the thermodynamic properties of a polar fluid. Our theory is applied to a dipolar hard sphere fluid as well as interaction site models of polar fluids such as water, where the electrostatic contribution to their thermodynamic properties can be obtained accurately.

Design of 280 GHz feedhorn-coupled TES arrays for the balloon-borne polarimeter SPIDER

NASA Astrophysics Data System (ADS)

Hubmayr, Johannes; Austermann, Jason E.; Beall, James A.; Becker, Daniel T.; Benton, Steven J.; Bergman, A. Stevie; Bond, J. Richard; Bryan, Sean; Duff, Shannon M.; Duivenvoorden, Adri J.; Eriksen, H. K.; Filippini, Jeffrey P.; Fraisse, A.; Galloway, Mathew; Gambrel, Anne E.; Ganga, K.; Grigorian, Arpi L.; Gualtieri, Riccardo; Gudmundsson, Jon E.; Hartley, John W.; Halpern, M.; Hilton, Gene C.; Jones, William C.; McMahon, Jeffrey J.; Moncelsi, Lorenzo; Nagy, Johanna M.; Netterfield, C. B.; Osherson, Benjamin; Padilla, Ivan; Rahlin, Alexandra S.; Racine, B.; Ruhl, John; Rudd, T. M.; Shariff, J. A.; Soler, J. D.; Song, Xue; Ullom, Joel N.; Van Lanen, Jeff; Vissers, Michael R.; Wehus, I. K.; Wen, Shyang; Wiebe, D. V.; Young, Edward

2016-07-01

We describe 280 GHz bolometric detector arrays that instrument the balloon-borne polarimeter spider. A primary science goal of spider is to measure the large-scale B-mode polarization of the cosmic microwave background (cmb) in search of the cosmic-inflation, gravitational-wave signature. 280 GHz channels aid this science goal by constraining the level of B-mode contamination from galactic dust emission. We present the focal plane unit design, which consists of a 16x16 array of conical, corrugated feedhorns coupled to a monolithic detector array fabricated on a 150 mm diameter silicon wafer. Detector arrays are capable of polarimetric sensing via waveguide probe-coupling to a multiplexed array of transition-edge-sensor (TES) bolometers. The spider receiver has three focal plane units at 280 GHz, which in total contains 765 spatial pixels and 1,530 polarization sensitive bolometers. By fabrication and measurement of single feedhorns, we demonstrate 14.7° FHWM Gaussian-shaped beams with <1% ellipticity in a 30% fractional bandwidth centered at 280 GHz. We present electromagnetic simulations of the detection circuit, which show 94% band-averaged, single-polarization coupling efficiency, 3% reflection and 3% radiative loss. Lastly, we demonstrate a low thermal conductance bolometer, which is well-described by a simple TES model and exhibits an electrical noise equivalent power (NEP) = 2.6 x 10-17 W/√Hz, consistent with the phonon noise prediction.

Active experiments using rocket-borne shaped charge barium releases. [solar-terrestrial magnetospheric physics

NASA Technical Reports Server (NTRS)

Wescott, E. M.; Davis, T. N.

1980-01-01

A reliable payload system and scaled down shaped charges were developed for carrying out experiments in solar-terrestrial magnetospheric physics. Four Nike-Tomahawk flights with apogees near 450 km were conducted to investigate magnetospheric electric fields, and two Taurus-Tomahawk rockets were flown in experiments on the auroral acceleration process in discrete auroras. In addition, a radial shaped charge was designed for plasma perturbation experiments.

The special theory of relativity as applied to the Born-Oppenheimer-Huang approach

NASA Astrophysics Data System (ADS)

Baer, Michael

2017-07-01

In two recent publications (Int. J. Quant. Chem. 114, 1645 (2014) and Mole. Phys. 114, 227 (2016)) it was shown that the Born-Hwang (BH) treatment of a molecular system perturbed by an external field yields a set of decoupled vectorial wave equations, just like in electro-magnetism. This finding led us to declare on the existence of a new type of Fields, which were termed Molecular Fields. The fact that such fields exist implies that at the vicinity of conical intersections exist a mechanism that transforms a passing-by electric beam into a field which differs from the original electric field. This situation is reminiscent of what is encountered in astronomy where Black Holes formed by massive stars may affect the nature of a near-by beam of light. Thus, if the non-adiabatic-coupling-terms (NACT) with their singular points may affect the nature of such a beam (see the above two publications), then it would be interesting to know to what extend NACTs (and consequently also the BH equation) will be affected by the special theory of relativity as introduced by Dirac. Indeed, while applying the Dirac approach we derived the relativistic affected NACTs as well as the corresponding BH equation.

Another Mexican birthweight paradox? The role of residential enclaves and neighborhood poverty in the birthweight of Mexican-origin infants.

PubMed

Osypuk, Theresa L; Bates, Lisa M; Acevedo-Garcia, Dolores

2010-02-01

Examining whether contextual factors influence the birth outcomes of Mexican-origin infants in the US may contribute to assessing rival explanations for the so-called Mexican health paradox. We examined whether birthweight among infants born to Mexican-origin women in the US was associated with Mexican residential enclaves and exposure to neighborhood poverty, and whether these associations were modified by nativity (i.e. mother's place of birth). We calculated metropolitan indices of neighborhood exposure to Mexican-origin population and poverty for the Mexican-origin population, and merged with individual-level, year 2000 natality data (n=490,332). We distinguished between neighborhood exposure to US-born Mexican-origin population (i.e. ethnic enclaves) and neighborhood exposure to foreign-born (i.e. Mexico-born) Mexican-origin population (i.e. immigrant enclaves). We used 2-level hierarchical linear regression models adjusting for individual, metropolitan, and regional covariates and stratified by nativity. We found that living in metropolitan areas with high residential segregation of US-born Mexican-origin residents (i.e. high prevalence of ethnic enclaves) was associated with lower birthweight for infants of US-born Mexican-origin mothers before and after covariate adjustment. When simultaneously adjusting for exposure to ethnic and immigrant enclaves, the latter became positively associated with birthweight and the negative effect of the former increased, among US-born mothers. We found no contextual birthweight associations for mothers born in Mexico in adjusted models. Our findings highlight a differential effect of context by nativity, and the potential health effects of ethnic enclaves, which are possibly a marker of downward assimilation, among US-born Mexican-origin women. Copyright 2009 Elsevier Ltd. All rights reserved.

A shock absorber model for structure-borne noise analyses

NASA Astrophysics Data System (ADS)

Benaziz, Marouane; Nacivet, Samuel; Thouverez, Fabrice

2015-08-01

Shock absorbers are often responsible for undesirable structure-borne noise in cars. The early numerical prediction of this noise in the automobile development process can save time and money and yet remains a challenge for industry. In this paper, a new approach to predicting shock absorber structure-borne noise is proposed; it consists in modelling the shock absorber and including the main nonlinear phenomena responsible for discontinuities in the response. The model set forth herein features: compressible fluid behaviour, nonlinear flow rate-pressure relations, valve mechanical equations and rubber mounts. The piston, base valve and complete shock absorber model are compared with experimental results. Sensitivity of the shock absorber response is evaluated and the most important parameters are classified. The response envelope is also computed. This shock absorber model is able to accurately reproduce local nonlinear phenomena and improves our state of knowledge on potential noise sources within the shock absorber.

From puddles to planet: modeling approaches to vector-borne diseases at varying resolution and scale.

PubMed

Eckhoff, Philip A; Bever, Caitlin A; Gerardin, Jaline; Wenger, Edward A; Smith, David L

2015-08-01

Since the original Ross-Macdonald formulations of vector-borne disease transmission, there has been a broad proliferation of mathematical models of vector-borne disease, but many of these models retain most to all of the simplifying assumptions of the original formulations. Recently, there has been a new expansion of mathematical frameworks that contain explicit representations of the vector life cycle including aquatic stages, multiple vector species, host heterogeneity in biting rate, realistic vector feeding behavior, and spatial heterogeneity. In particular, there are now multiple frameworks for spatially explicit dynamics with movements of vector, host, or both. These frameworks are flexible and powerful, but require additional data to take advantage of these features. For a given question posed, utilizing a range of models with varying complexity and assumptions can provide a deeper understanding of the answers derived from models. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Health spending among working-age immigrants with disabilities compared to those born in the US.

PubMed

Tarraf, Wassim; Mahmoudi, Elham; Dillaway, Heather E; González, Hector M

2016-07-01

Immigrants have disparate access to health care. Disabilities can amplify their health care burdens. Examine how US- and foreign-born working-age adults with disabilities differ in their health care spending patterns. Medical Expenditures Panel Survey yearly-consolidated files (2000-2010) on working-age adults (18-64 years) with disabilities. We used three operational definitions of disability: physical, cognitive, and sensory. We examined annual total, outpatient/office-based, prescription medication, inpatient, and emergency department (ED) health expenditures. We tested bivariate logistic and linear regression models to, respectively, assess unadjusted group differences in the propensity to spend and average expenditures. Second, we used multivariable two-part models to estimate and test per-capita expenditures adjusted for predisposing, enabling, health need and behavior indicators. Adjusted for age and sex differences, US-born respondents with physical, cognitive, sensory spent on average $2977, $3312, and $2355 more in total compared to their foreign-born counterparts (P < 0.01). US-born spending was also higher across the four types of health care expenditures considered. Adjusting for the behavioral model factors, especially predisposing and enabling indicators, substantially reduced nativity differences in overall, outpatient/office-based and medication spending but not in inpatient and ED expenditures. Working-age immigrants with disabilities have lower levels of health care use and expenditures compared to their US-born counterparts. Affordable Care Act provisions aimed at increasing access to insurance and primary care can potentially align the consumption patterns of US- and foreign-born disabled working-age adults. More work is needed to understand the pathways leading to differences in hospital and prescription medication care. Copyright © 2016 Elsevier Inc. All rights reserved.

Health Spending Among Working-Age Immigrants With Disabilities Compared To Those Born In The US

PubMed Central

Tarraf, Wassim; Mahmoudi, Elham; Dillaway, Heather E; Gonzalez, Hector M.

2016-01-01

Background Immigrants have disparate access to healthcare. Disabilities can amplify their healthcare burdens. Objective/Hypothesis Examine how US- and foreign-born working-age adults with disabilities differ in their healthcare spending patterns. Methods Medical Expenditures Panel Survey yearly-consolidated files (2000-2010) on working-age adults (18-64 years) with disabilities. We used three operational definitions of disability: physical, cognitive, and sensory. We examined annual total, outpatient/office-based, prescription medication, inpatient, and emergency department (ED) health expenditures. We tested bivariate logistic and linear regression models to, respectively, assess unadjusted group differences in the propensity to spend and average expenditures. Second, we used multivariable two-part models to estimate and test per-capita expenditures adjusted for predisposing, enabling, health need and behavior indicators. Results Adjusted for age and sex differences, US-born respondents with physical, cognitive, sensory spent on average $2,977, $3,312, and $2,355 more in total compared to their foreign-born counterparts (P<0.01). US-born spending was also higher across the four types of healthcare expenditures considered. Adjusting for the behavioral model factors, especially predisposing and enabling indicators, substantially reduced nativity differences in overall, outpatient/office-based and medication spending but not in inpatient and ED expenditures. Conclusions Working-age immigrants with disabilities have lower levels of healthcare use and expenditures compared to their US-born counterparts. Affordable Care Act provisions aimed at increasing access to insurance and primary care can potentially align the consumption patterns of US- and foreign-born disabled working-age adults. More work is needed to understand the pathways leading to differences in hospital and prescription medication care. PMID:26917103

Controlling Thermodynamic Properties of Ferromagnetic Group-IV Graphene-Like Nanosheets by Dilute Charged Impurity

NASA Astrophysics Data System (ADS)

Yarmohammadi, Mohsen; Mirabbaszadeh, Kavoos

2017-05-01

Using the Kane-Mele Hamiltonian, Dirac theory and self-consistent Born approximation, we investigate the effect of dilute charged impurity on the electronic heat capacity and magnetic susceptibility of two-dimensional ferromagnetic honeycomb structure of group-IV elements including silicene, germanene and stanene within the Green’s function approach. We also find these quantities in the presence of applied external electric field. Our results show that the silicene (stanene) has the maximum (minimum) heat capacity and magnetic susceptibility at uniform electric fields. From the behavior of theses quantities, the band gap has been changed with impurity concentration, impurity scattering strength and electric field. The analysis on the impurity-dependent magnetic susceptibility curves shows a phase transition from ferromagnetic to paramagnetic and antiferromagnetic phases. Interestingly, electronic heat capacity increases (decreases) with impurity concentration in silicene (germanene and stanene) structure.

Imitation by Second-Borns in Adult-Sibling Dyads.

ERIC Educational Resources Information Center

Hodapp, Albert F.; LaVoie, Joseph C.

Five- to seven-year-old second-born children from white, middle-class, intact families were the subjects for this study. Older siblings served as role model for each child, and the parent surrogate models were selected from a pool and trained to act as the child's real parent. The imitation task emphasized verbal, postural, and motor responses of…

First Experimental In Vivo Model of Enhanced Dengue Disease Severity through Maternally Acquired Heterotypic Dengue Antibodies

PubMed Central

Ng, Jowin Kai Wei; Zhang, Summer Lixin; Tan, Hwee Cheng; Yan, Benedict; Maria Martinez Gomez, Julia; Tan, Wei Yu; Lam, Jian Hang; Tan, Grace Kai Xin; Ooi, Eng Eong; Alonso, Sylvie

2014-01-01

Dengue (DEN) represents the most serious arthropod-borne viral disease. DEN clinical manifestations range from mild febrile illness to life-threatening hemorrhage and vascular leakage. Early epidemiological observations reported that infants born to DEN-immune mothers were at greater risk to develop the severe forms of the disease upon infection with any serotype of dengue virus (DENV). From these observations emerged the hypothesis of antibody-dependent enhancement (ADE) of disease severity, whereby maternally acquired anti-DENV antibodies cross-react but fail to neutralize DENV particles, resulting in higher viremia that correlates with increased disease severity. Although in vitro and in vivo experimental set ups have indirectly supported the ADE hypothesis, direct experimental evidence has been missing. Furthermore, a recent epidemiological study has challenged the influence of maternal antibodies in disease outcome. Here we have developed a mouse model of ADE where DENV2 infection of young mice born to DENV1-immune mothers led to earlier death which correlated with higher viremia and increased vascular leakage compared to DENV2-infected mice born to dengue naïve mothers. In this ADE model we demonstrated the role of TNF-α in DEN-induced vascular leakage. Furthermore, upon infection with an attenuated DENV2 mutant strain, mice born to DENV1-immune mothers developed lethal disease accompanied by vascular leakage whereas infected mice born to dengue naïve mothers did no display any clinical manifestation. In vitro ELISA and ADE assays confirmed the cross-reactive and enhancing properties towards DENV2 of the serum from mice born to DENV1-immune mothers. Lastly, age-dependent susceptibility to disease enhancement was observed in mice born to DENV1-immune mothers, thus reproducing epidemiological observations. Overall, this work provides direct in vivo demonstration of the role of maternally acquired heterotypic dengue antibodies in the enhancement of dengue disease severity and offers a unique opportunity to further decipher the mechanisms involved. PMID:24699622

A survey of solutions in a gravitational Born-Infeld theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chern, Jann-Long, E-mail: chern@math.ncu.edu.tw; Yang, Sze-Guang, E-mail: sgyang@math.ncu.edu.tw

2014-03-15

An elliptic equation that arises from a cosmic string model with the action of the Born-Infeld nonlinear electromagnetism, is considered. We classify and establish the uniqueness of radially symmetric solutions.

A Reaction-Diffusion Model of Vector-Borne Disease with Periodic Delays

NASA Astrophysics Data System (ADS)

Wu, Ruiwen; Zhao, Xiao-Qiang

2018-06-01

A vector-borne disease is caused by a range of pathogens and transmitted to hosts through vectors. To investigate the multiple effects of the spatial heterogeneity, the temperature sensitivity of extrinsic incubation period and intrinsic incubation period, and the seasonality on disease transmission, we propose a nonlocal reaction-diffusion model of vector-borne disease with periodic delays. We introduce the basic reproduction number R_0 for this model and then establish a threshold-type result on its global dynamics in terms of R_0 . In the case where all the coefficients are constants, we also prove the global attractivity of the positive constant steady state when R_0>1 . Numerically, we study the malaria transmission in Maputo Province, Mozambique.

Cohort Differences in Cognitive Aging and Terminal Decline in the Seattle Longitudinal Study

PubMed Central

Gerstorf, Denis; Ram, Nilam; Hoppmann, Christiane; Willis, Sherry L.; Schaie, K. Warner

2011-01-01

Life span researchers have long been interested in how and why fundamental aspects of human ontogeny differ between cohorts of people who have lived through different historical epochs. When examined at the same age, later born cohorts are often cognitively and physically fitter than earlier born cohorts. Less is known, however, about cohort differences in the rate of cognitive aging and if, at the very end of life, pervasive mortality-related processes overshadow and minimize cohort differences. We used data on 5 primary mental abilities from the Seattle Longitudinal Study (Schaie, 2005) to compare both age-related and mortality-related changes between earlier born cohorts (1886–1913) and later born cohorts (1914–1948). Our models covary for several individual and cohort differences in central indicators of life expectancy, education, health, and gender. Age-related growth models corroborate and extend earlier findings by documenting level differences at age 70 of up to 0.50 SD and less steep rates of cognitive aging on all abilities between 50 and 80 years of age favoring the later born cohort. In contrast, mortality-related models provide limited support for positive cohort differences. The later born cohort showed steeper mortality-related declines. We discuss possible reasons why often reported positive secular trends in age-related processes may not generalize to the vulnerable segment of the population that is close to death and suggest routes for further inquiry. PMID:21517155

A gravity model for the spread of a pollinator-borne plant pathogen.

PubMed

Ferrari, Matthew J; Bjørnstad, Ottar N; Partain, Jessica L; Antonovics, Janis

2006-09-01

Many pathogens of plants are transmitted by arthropod vectors whose movement between individual hosts is influenced by foraging behavior. Insect foraging has been shown to depend on both the quality of hosts and the distances between hosts. Given the spatial distribution of host plants and individual variation in quality, vector foraging patterns may therefore produce predictable variation in exposure to pathogens. We develop a "gravity" model to describe the spatial spread of a vector-borne plant pathogen from underlying models of insect foraging in response to host quality using the pollinator-borne smut fungus Microbotryum violaceum as a case study. We fit the model to spatially explicit time series of M. violaceum transmission in replicate experimental plots of the white campion Silene latifolia. The gravity model provides a better fit than a mean field model or a model with only distance-dependent transmission. The results highlight the importance of active vector foraging in generating spatial patterns of disease incidence and for pathogen-mediated selection for floral traits.

The antibiotic activity and mechanisms of sugarcane (Saccharum officinarum L.) bagasse extract against food-borne pathogens.

PubMed

Zhao, Yi; Chen, Mingshun; Zhao, Zhengang; Yu, Shujuan

2015-10-15

Sugarcane bagasse contains natural compositions that can significantly inhibit food-borne pathogens growth. In the present study, the phenolic content in sugarcane bagasse was detected as higher than 4 mg/g dry bagasse, with 470 mg quercetin/g polyphenol. The sugarcane bagasse extract showed bacteriostatic activity against the growth of Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salomonella typhimurium. Additionally, the sugarcane bagasse extract can increase the electric conductivity of bacterial cell suspensions causing cellular leaking of electrolytes. Results of sodium dodecyl sulfate polyacrylamide gel electrophoresis suggested the antibacterial mechanism was probably due to the damaged cellular proteins by sugarcane bagasse extract. The results of scanning electron microscopy and transmission electron microscopy showed that the sugarcane bagasse extract might change cell morphology and internal structure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Design and adaptation of a folded split ring resonator antenna for use in an animal-borne sensor

NASA Astrophysics Data System (ADS)

Dodson, S. C.; Wiid, P. G.; Niesler, T. R.

2018-03-01

We present the design, optimisation and practical evaluation of a folded split ring resonator (FSRR) antenna for the purpose of radio communication with an animal-borne sensor. We show that the measurements agree with the simulated results and that we are able to produce an electrically small antenna with low mismatch, high radiation efficiency and a quasi-isotropic radiation pattern. We then adapt the topology of the design from a circular to a rectangular shape, to completely fit inside the sensor enclosure. A quasi-isotropic pattern is maintained as well as low mismatch by appropriate tuning. There is a decrease in radiation efficiency which may be countered by a thinner substrate and retuning. We conclude that the adapted FSRR antenna is a suitable design for our application.

Models for the effects of host movement in vector-borne disease systems.

PubMed

Cosner, Chris

2015-12-01

Host and/or vector movement patterns have been shown to have significant effects in both empirical studies and mathematical models of vector-borne diseases. The processes of economic development and globalization seem likely to make host movement even more important in the future. This article is a brief survey of some of the approaches that have been used to study the effects of host movement in analytic mathematical models for vector-borne diseases. It describes the formulation and interpretation of various types of spatial models and describes a few of the conclusions that can be drawn from them. It is not intended to be comprehensive but rather to provide sufficient background material and references to the literature to serve as an entry point into this area of research for interested readers. Copyright © 2015 Elsevier Inc. All rights reserved.

Estimating secular changes in longitudinal growth patterns underlying adult height with the QEPS model: the Grow Up Gothenburg cohorts.

PubMed

Holmgren, Anton; Niklasson, Aimon; Nierop, Andreas F M; Gelander, Lars; Aronson, A Stefan; Sjöberg, Agneta; Lissner, Lauren; Albertsson-Wikland, Kerstin

2018-05-23

Over the past 150 years, humans have become taller, and puberty has begun earlier. It is unclear if these changes are continuing in Sweden, and how longitudinal growth patterns are involved. We aimed to evaluate the underlying changes in growth patterns from birth to adulthood by QEPS estimates in two Swedish cohorts born in 1974 and 1990. Growth characteristics of the longitudinal 1974 and 1990-birth cohorts (n = 4181) were compared using the QEPS model together with adult heights. There was more rapid fetal/infancy growth in girls/boys born in 1990 compared to 1974, as shown by a faster Etimescale and they were heavier at birth. The laterborn were taller also in childhood as shown by a higher Q-function. Girls born in 1990 had earlier and more pronounced growth during puberty than girls born in 1974. Individuals in the 1990 cohort attained greater adult heights than those in the 1974 cohort; 6 mm taller for females and 10 mm for males. A positive change in adult height was attributed to more growth during childhood in both sexes and during puberty for girls. The QEPS model proved to be effective detecting small changes of growth patterns, between two longitudinal growth cohorts born only 16 years apart.

Big Bang Day: 5 Particles - 1. The Electron

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2009-10-07

Simon Singh looks at the stories behind the discovery of 5 of the universe's most significant subatomic particles: the Electron, the Quark, the Anti-particle, the Neutrino and the "next particle". 1. The Electron Just over a century ago, British physicist J.J. Thompson experimenting with electric currents and charged particles inside empty glass tubes, showed that atoms are divisible into indivisible elementary particles. But how could atoms be built up of these so called "corpuscles"? An exciting 30 year race ensued, to grasp the planetary model of the atom with its orbiting electrons, and the view inside the atom was born.more » Whilst the number of electrons around the nucleus of an atom determines their the chemistry of all elements, the power of electrons themselves have been harnessed for everyday use: electron beams for welding,cathode ray tubes and radiation therapy.« less

How will climate change pathways and mitigation options alter incidence of vector-borne diseases? A framework for leishmaniasis in South and Meso-America

PubMed Central

Masante, Dario; Golding, Nicholas; Pigott, David; Day, John C.; Ibañez-Bernal, Sergio; Kolb, Melanie; Jones, Laurence

2017-01-01

The enormous global burden of vector-borne diseases disproportionately affects poor people in tropical, developing countries. Changes in vector-borne disease impacts are often linked to human modification of ecosystems as well as climate change. For tropical ecosystems, the health impacts of future environmental and developmental policy depend on how vector-borne disease risks trade off against other ecosystem services across heterogeneous landscapes. By linking future socio-economic and climate change pathways to dynamic land use models, this study is amongst the first to analyse and project impacts of both land use and climate change on continental-scale patterns in vector-borne diseases. Models were developed for cutaneous and visceral leishmaniasis in the Americas—ecologically complex sand fly borne infections linked to tropical forests and diverse wild and domestic mammal hosts. Both diseases were hypothesised to increase with available interface habitat between forest and agricultural or domestic habitats and with mammal biodiversity. However, landscape edge metrics were not important as predictors of leishmaniasis. Models including mammal richness were similar in accuracy and predicted disease extent to models containing only climate and land use predictors. Overall, climatic factors explained 80% and land use factors only 20% of the variance in past disease patterns. Both diseases, but especially cutaneous leishmaniasis, were associated with low seasonality in temperature and precipitation. Since such seasonality increases under future climate change, particularly under strong climate forcing, both diseases were predicted to contract in geographical extent to 2050, with cutaneous leishmaniasis contracting by between 35% and 50%. Whilst visceral leishmaniasis contracted slightly more under strong than weak management for carbon, biodiversity and ecosystem services, future cutaneous leishmaniasis extent was relatively insensitive to future alternative socio-economic pathways. Models parameterised at narrower geographical scales may be more sensitive to land use pattern and project more substantial changes in disease extent under future alternative socio-economic pathways. PMID:29020041

How will climate change pathways and mitigation options alter incidence of vector-borne diseases? A framework for leishmaniasis in South and Meso-America.

PubMed

Purse, Bethan V; Masante, Dario; Golding, Nicholas; Pigott, David; Day, John C; Ibañez-Bernal, Sergio; Kolb, Melanie; Jones, Laurence

2017-01-01

The enormous global burden of vector-borne diseases disproportionately affects poor people in tropical, developing countries. Changes in vector-borne disease impacts are often linked to human modification of ecosystems as well as climate change. For tropical ecosystems, the health impacts of future environmental and developmental policy depend on how vector-borne disease risks trade off against other ecosystem services across heterogeneous landscapes. By linking future socio-economic and climate change pathways to dynamic land use models, this study is amongst the first to analyse and project impacts of both land use and climate change on continental-scale patterns in vector-borne diseases. Models were developed for cutaneous and visceral leishmaniasis in the Americas-ecologically complex sand fly borne infections linked to tropical forests and diverse wild and domestic mammal hosts. Both diseases were hypothesised to increase with available interface habitat between forest and agricultural or domestic habitats and with mammal biodiversity. However, landscape edge metrics were not important as predictors of leishmaniasis. Models including mammal richness were similar in accuracy and predicted disease extent to models containing only climate and land use predictors. Overall, climatic factors explained 80% and land use factors only 20% of the variance in past disease patterns. Both diseases, but especially cutaneous leishmaniasis, were associated with low seasonality in temperature and precipitation. Since such seasonality increases under future climate change, particularly under strong climate forcing, both diseases were predicted to contract in geographical extent to 2050, with cutaneous leishmaniasis contracting by between 35% and 50%. Whilst visceral leishmaniasis contracted slightly more under strong than weak management for carbon, biodiversity and ecosystem services, future cutaneous leishmaniasis extent was relatively insensitive to future alternative socio-economic pathways. Models parameterised at narrower geographical scales may be more sensitive to land use pattern and project more substantial changes in disease extent under future alternative socio-economic pathways.

Sound transmission of cavity walls due to structure borne transmission via point and line connections.

PubMed

Davy, John L

2012-08-01

The author has published equations for predicting the air borne sound transmission of double leaf cavity walls due to the structure borne sound transmission across the air cavity via (possibly resilient) line connections, but has never published the full derivation of these equations. The author also derived equations for the case when the connections are rigid point connections but has never used them or published them or their derivations. This paper will present the full derivation of the author's theory of the air borne sound transmission of double leaf cavity walls due to the structure borne sound transmission across the air cavity via point or line connections which are modeled as four pole networks. The theoretical results will be compared with experimental results on wooden stud cavity walls from the National Research Council of Canada because the screw spacing is given for these results. This enables connections via studs and screws to be modeled as point connections and avoids the need to make any assumptions about the compliance of the equivalent point or line connections.

Early school attainment in late-preterm infants.

PubMed

Peacock, Philip J; Henderson, John; Odd, David; Emond, Alan

2012-02-01

To investigate whether infants born late-preterm have poorer school attainment compared to those born at term. This study used data from the Avon Longitudinal Study of Parents and Children. Key stage one (KS1) school assessment results were obtained from local education authorities. Logistic regression models were used to investigate the effect of gestation, that is, late-preterm (32-36 weeks) versus term (37-41 weeks), on success in KS1 teacher assessments. Regression models were adjusted for potential confounders, including maternal education and markers of socioeconomic status. There were 12 089 term infants and 734 late-preterm infants. 71% of late-preterm children were successful in KS1 assessments compared to 79% of those born at term (OR 0.64 (95% CI 0.53 to 0.78); p<0.001). This difference persisted on adjusting for potential confounders (OR 0.74 (95% CI 0.59 to 0.92); p=0.007). Children born late-preterm are less likely to be successful in early school assessments than those born at term. This group of vulnerable children warrants closer surveillance for early identification of potential educational failure.

Acculturation and drug addiction stigma among Latinos and African Americans: An examination of a church-based sample

PubMed Central

Flórez, Karen R.; Derose, Kathryn Pitkin; Breslau, Joshua; Griffin, Beth Ann; Haas, Ann C.; Kanouse, David E.; Stucky, Brian D.; Williams, Malcolm V.

2015-01-01

Background Substance use patterns among Latinos likely reflect changes in attitudes resulting from acculturation, but little is known about Latinos’ attitudes regarding drug addiction. Methods We surveyed a church-based sample of Latinos and African Americans (N=1,235) about attitudes toward drug addiction and socio-demographics. Linear regression models compared Latino subgroups with African-Americans. Results In adjusted models, Latinos had significantly higher drug addiction stigma scores compared to African Americans across all subgroups (U.S.-born Latinos, β = 0.22, p<.05; foreign-born Latinos with high English proficiency, β = 0.30, p<.05; and foreign-born Latinos with low English proficiency, β =0.49, p<.001). Additionally, Latinos with low English proficiency had significantly higher mean levels of drug use stigma compared Latinos with high proficiency (both foreign-born and U.S.-born). Discussion In this church-affiliated sample, Latinos’ drug addiction stigma decreases with acculturation, but remains higher among the most acculturated Latinos compared to African-Americans. These attitudes may pose a barrier to treatment for Latino drug users. PMID:25612923

Interpretations and pitfalls in modelling vector-transmitted infections.

PubMed

Amaku, M; Azevedo, F; Burattini, M N; Coutinho, F A B; Lopez, L F; Massad, E

2015-07-01

In this paper we propose a debate on the role of mathematical models in evaluating control strategies for vector-borne infections. Mathematical models must have their complexity adjusted to their goals, and we have basically two classes of models. At one extreme we have models that are intended to check if our intuition about why a certain phenomenon occurs is correct. At the other extreme, we have models whose goals are to predict future outcomes. These models are necessarily very complex. There are models in between these classes. Here we examine two models, one of each class and study the possible pitfalls that may be incurred. We begin by showing how to simplify the description of a complicated model for a vector-borne infection. Next, we examine one example found in a recent paper that illustrates the dangers of basing control strategies on models without considering their limitations. The model in this paper is of the second class. Following this, we review an interesting paper (a model of the first class) that contains some biological assumptions that are inappropriate for dengue but may apply to other vector-borne infections. In conclusion, we list some misgivings about modelling presented in this paper for debate.

Quantitative PCR for Tracking the Megaplasmid-Borne Biodegradation Potential of a Model Sphingomonad

PubMed Central

Hartmann, Erica M.; Badalamenti, Jonathan P.; Krajmalnik-Brown, Rosa

2012-01-01

We developed a quantitative PCR method for tracking the dxnA1 gene, the initial, megaplasmid-borne gene in Sphingomonas wittichii RW1's dibenzo-p-dioxin degradation pathway. We used this method on complex environmental samples and report on growth of S. wittichii RW1 in landfill leachate, thus furnishing a novel tool for monitoring megaplasmid-borne, dioxygenase-encoding genes. PMID:22492441

South Asian-White health inequalities in Canada: intersections with gender and immigrant status.

PubMed

Veenstra, Gerry; Patterson, Andrew C

2016-12-01

We apply intersectionality theory to health inequalities in Canada by investigating whether South Asian-White health inequalities are conditioned by gender and immigrant status in a synergistic way. Our dataset comprised 10 cycles (2001-2013) of the Canadian Community Health Survey. Using binary logistic regression modeling, we examined South Asian-White inequalities in self-rated health, diabetes, hypertension and asthma before and after controlling for potentially explanatory factors. Models were calculated separately in subsamples of native-born women, native-born men, immigrant women and immigrant men. South Asian immigrants had higher odds of fair/poor self-rated health, diabetes and hypertension than White immigrants. Native-born South Asian men had higher odds of fair/poor self-rated health than native-born White men and native-born South Asian women had lower odds of hypertension than native-born White women. Education, household income, smoking, physical activity and body mass index did little to explain these associations. The three-way interaction between racial identity, gender and immigrant status approached statistical significance for hypertension but not for self-rated health and asthma. Our findings provide modest support for the intersectionally inspired principle that combinations of identities derived from race, gender and nationality constitute sui generis categories in the manifestation of health outcomes.

Comparison Analysis of Recognition Algorithms of Forest-Cover Objects on Hyperspectral Air-Borne and Space-Borne Images

NASA Astrophysics Data System (ADS)

Kozoderov, V. V.; Kondranin, T. V.; Dmitriev, E. V.

2017-12-01

The basic model for the recognition of natural and anthropogenic objects using their spectral and textural features is described in the problem of hyperspectral air-borne and space-borne imagery processing. The model is based on improvements of the Bayesian classifier that is a computational procedure of statistical decision making in machine-learning methods of pattern recognition. The principal component method is implemented to decompose the hyperspectral measurements on the basis of empirical orthogonal functions. Application examples are shown of various modifications of the Bayesian classifier and Support Vector Machine method. Examples are provided of comparing these classifiers and a metrical classifier that operates on finding the minimal Euclidean distance between different points and sets in the multidimensional feature space. A comparison is also carried out with the " K-weighted neighbors" method that is close to the nonparametric Bayesian classifier.

Origin of the Counterintuitive Dynamic Charge in the Transition-Metal Dichalcogenides

NASA Astrophysics Data System (ADS)

Pike, Nicholas; van Troeye, Benoit; Dewandre, Antoine; Gonze, Xavier; Verstraete, Matthieu

Our recent first-principles calculations of the electronic and vibrational properties of the hexagonal transition-metal dichalcogenides reveal that their Born effective charges display a counterintuitive sign when compared to most other materials or transition-metal dichalcogenides with trigonal symmetry. We determine the origin of this counterintuitive sign by calculating the electronic, vibrational, and optical properties of these systems. We show that the sign of the Born effective charge is directly related to the electric field response of the electronic density, and, in turn, to the bonding characteristics of the material.There is a filled anti-bonding molecular orbital at the Fermi level, which is localized on the transition-metal atom and corresponds to a form of solid state π back-bonding in these material. We propose a method of determining if other materials display a similar counterintuitive sign, based on their bonding characteristics, and propose experiments which could measure the sign of the Born effective charge using different spectroscopies. The authors acknowledge the Belgian Fonds National de la Recherche Scientifique FNRS under PDR T.1077.15-1/7, a FRIA Grant, ULg, and from the Communauté Française de Belgique (ARC AIMED 15/19-09).

Balloon Measurements of Electric Fields in Thunderstorms: A Modern Version of Benjamin Franklin's Kite

NASA Astrophysics Data System (ADS)

Marshall, T. C.; Stolzenburg, M.

2006-12-01

One of Benjamin Franklin's most famous experiments was the kite experiment, which showed that thunderstorms are electrically charged. It is not as commonly noted that the kite experiment was also one of the the first attempts to make an in situ measurement of any storm parameter. Franklin realized the importance of making measurements close to and within storms, and this realization has been shared by later atomspheric scientists. In this presentation we focus on a modern version of Franklin's kite--instrumented balloons--used for in situ measurements of electric field and other storm parameters. In particular, most of our knowledge of the charge structure inside thunderstorms is based on balloon soundings of electric field. Balloon measurements of storm electricity began with the work of Simpson and colleagues in the 1930's and 1940's. The next major instrumentation advances were made by Winn and colleagues in the 1970's and 1980's. Today's instruments are digital versions of the Winn design. We review the main instrument techniques that have allowed balloons to be the worthy successors to kites. We also discuss some of the key advances in our understanding of thunderstorm electrification made with in situ balloon-borne instruments.

Basics of applied geothermal engineering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wehlage, E.F.

1976-01-01

The following chapters are included: (1) born of fire, (2) milestones with tectonics, (3) a world in geothermal review, (4) simple mechanical and electrical facts for geothermal, (5) elementary hydraulics and pumping, (6) elementary heat, (7) application of steam, (8) geothermal hydroponics, (9) designing for a geothermal diary, (10) review of geothermal prime movers for power production, (11) design procedures-geothermal house heating, (12) cooling with geothermal refrigeration, and (13) geothermal synthesis-new heat for the world. (MOW)

Modelling of high-frequency structure-borne sound transmission on FEM grids using the Discrete Flow Mapping technique

NASA Astrophysics Data System (ADS)

Hartmann, Timo; Tanner, Gregor; Xie, Gang; Chappell, David; Bajars, Janis

2016-09-01

Dynamical Energy Analysis (DEA) combined with the Discrete Flow Mapping technique (DFM) has recently been introduced as a mesh-based high frequency method modelling structure borne sound for complex built-up structures. This has proven to enhance vibro-acoustic simulations considerably by making it possible to work directly on existing finite element meshes circumventing time-consuming and costly re-modelling strategies. In addition, DFM provides detailed spatial information about the vibrational energy distribution within a complex structure in the mid-to-high frequency range. We will present here progress in the development of the DEA method towards handling complex FEM-meshes including Rigid Body Elements. In addition, structure borne transmission paths due to spot welds are considered. We will present applications for a car floor structure.

Long-term cognitive outcomes of infants born moderately and late preterm.

PubMed

Odd, David Edward; Emond, Alan; Whitelaw, Andrew

2012-08-01

To investigate whether infants born late preterm have poorer cognitive outcomes than term-born infants. A cohort study based on the Avon Longitudinal Study of Parents and Children. Cognitive measures were assessed between the ages of 8 and 11 years. Exposure groups were defined as moderate/late preterm (32-36 weeks' gestation) or term (37-42 wk). Regression models were used to investigate the association between gestational age and IQ. Seven hundred and forty-one infants (5.4% of total eligible population; 422 males, 319 females; mean (SD) birthweight 2495 g [489]) were born between 32 and 36 weeks' gestation. The analysis was based on 6957 infants with IQ data at age 11 (50% of eligible infants). In the adjusted model, children born moderately and late preterm had similar IQ scores to peers born at term (mean difference [95% confidence interval] -0.18 [-1.88 to 1.52]). However, the preterm infants had a higher risk of having special educational needs at school (odds ratio 1.56 [1.18-2.07]). Despite an increased risk of special educational needs, there is little evidence of a reduction in IQ, memory, or attention measures at school age in children born between 32 and 36 weeks' gestation. Although interpretation is limited by the amount of missing data, further work is needed to identify why these infants have increased educational needs. © The Authors. Developmental Medicine & Child Neurology © 2012 Mac Keith Press.

Comparison of the temperature-mortality relationship in foreign born and native born died in France between 2000 and 2009

NASA Astrophysics Data System (ADS)

Mercereau, Luc; Todd, Nicolas; Rey, Gregoire; Valleron, Alain-Jacques

2017-10-01

The daily temperature-mortality relationship is typically U shaped. The temperature of minimum mortality (MMT) has been shown to vary in space (higher at lower latitudes) and time (higher in recent periods). This indicates human populations adapt to their local environment. The pace of this adaptation is unknown. The objective of this study was to investigate the differences in the temperature-mortality relationship in continental France between foreign born and natives. Source data were the 5,273,005 death certificates of individuals living in continental France between 2000 and 2009 at the time of their death. Foreign-born deaths ( N = 573,384) were matched 1:1 with a native-born death based on date of birth, sex, and place of death. Four regions of France based on similarity of their temperatures profiles were defined by unsupervised clustering. For each of these four regions, variations of all causes mortality with season and temperature of the day were modeled and compared between four groups of foreign born (Maghreb, sub-Saharan Africa, Southern Europe, and Northern Europe) and matched groups of natives. Overall, the temperature-mortality relationship and MMT were close in foreign born and in native born: The only difference between foreign born and native born concerned the attributable mortality to cold, found in several instances larger in foreign born. There are little differences in France between the temperature-mortality relationships in native born and in foreign born. This supports the hypothesis of an adaptation of these populations to the temperature patterns of continental France, which for those born in Africa differ markedly from the climatic pattern of their birth country.

Comparison of the temperature-mortality relationship in foreign born and native born died in France between 2000 and 2009.

PubMed

Mercereau, Luc; Todd, Nicolas; Rey, Gregoire; Valleron, Alain-Jacques

2017-10-01

The daily temperature-mortality relationship is typically U shaped. The temperature of minimum mortality (MMT) has been shown to vary in space (higher at lower latitudes) and time (higher in recent periods). This indicates human populations adapt to their local environment. The pace of this adaptation is unknown. The objective of this study was to investigate the differences in the temperature-mortality relationship in continental France between foreign born and natives. Source data were the 5,273,005 death certificates of individuals living in continental France between 2000 and 2009 at the time of their death. Foreign-born deaths (N = 573,384) were matched 1:1 with a native-born death based on date of birth, sex, and place of death. Four regions of France based on similarity of their temperatures profiles were defined by unsupervised clustering. For each of these four regions, variations of all causes mortality with season and temperature of the day were modeled and compared between four groups of foreign born (Maghreb, sub-Saharan Africa, Southern Europe, and Northern Europe) and matched groups of natives. Overall, the temperature-mortality relationship and MMT were close in foreign born and in native born: The only difference between foreign born and native born concerned the attributable mortality to cold, found in several instances larger in foreign born. There are little differences in France between the temperature-mortality relationships in native born and in foreign born. This supports the hypothesis of an adaptation of these populations to the temperature patterns of continental France, which for those born in Africa differ markedly from the climatic pattern of their birth country.

First- and second-born adolescents' decision-making autonomy throughout adolescence.

PubMed

Campione-Barr, Nicole; Lindell, Anna K; Short, Stephen D; Greer, Kelly Bassett; Drotar, Scott D

2015-12-01

First- and second-born adolescents' and their parents' perceptions of adolescents' decision-making autonomy were compared from ages 12 to 19 in a longitudinal sample of 145 predominantly White, middle class families. Utilizing a multivariate, multilevel modeling approach, differences in perceptions of adolescents' autonomy between parents and each adolescent, as well as by social-cognitive domain were examined. The present study found that when comparing parents' perceptions of their children at the same age, second-borns were granted more autonomy regarding conventional issues than first-borns during early adolescence, but by later adolescence first-borns were granted more autonomy regarding prudential issues than second-borns. However, comparisons between adolescents' and siblings' perceptions showed no differences. Potential reasons for, and implications of, differences in perceptions of adolescent autonomy are discussed. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Waterspout as a special type of atmospheric aerosol dusty plasma

NASA Astrophysics Data System (ADS)

Rantsev-Kartinov, Valentin A.

2004-11-01

An analysis of databases of photographic images of oceanic surface revealed the presence of oceanic skeletal structures (OSS) [1] Rantsev-Kartinov V.A., Preprint . The OSSs presumably differ from the formerly found skeletal structures (SS) (Phys. Lett. A 306 (2002) 175) only by the fact that OSS are filled in with the closely packed blocks of a smaller size, up to thin, tens of microns-sized capillaries. The SSs in the Earth atmosphere were suggested [1] to be produced during atmospheric electricity activity by the volcanic-born dust. The fall-out of such SSs on the oceanic surface is a material source of OSS. Here we suggest that an OSS block [1] in the form of vertically oriented floating cylinder may be a stimulator of waterspout (WS). The main body of WS may be interpreted as a special type of atmospheric aerosol dusty plasma, and WS column - as a long-lived filament, being formed in the process of electric breakdown between the cloud and oceanic surface. The charged water drops aerosol may behave similar to microdust and lift upward to the cloud by the electrostatic force. With such a capillary&;electrostatic model of WS, it appears possible to interpret many effects related to WS.

Hy-wire measurements of atmospheric potential

NASA Astrophysics Data System (ADS)

Holzworth, Robert H.

1984-02-01

A method of directly measuring the electric potential drop across the lowest portion of the atmosphere by using an apparatus called Hy-wire is described. This tethered balloon-borne system has been operated extensively at altitudes near 0.62 km at which voltages over 150 k V were measured with a high impedance device. Also described are measurements of system parameters such as system capacitance (5.6 pf/m), impedance (1010Ω), and response time (tens of seconds). Hy-wire measurements from an around the-clock experiment at Wallops Island, Va., having a characteristic repetitive diurnal pattern of variability exceeding 40% of the mean, are presented. This diurnal pattern is discussed in terms of both local and global current sources. A demonstration using Hy-wire as a lightning channel model is also presented. These experiments have so far been conducted at mid-latitudes but can also be flown from other locations in an effort to determine whether the lowest atmospheric electric circuit is affected by high altitude and possibly global current systems, and if so how much. The data presented in this paper are not definitive about the source of potential variations. The data are, however, representative of the new Hy-wire technique and demonstrative of the potential usefulness of this technique.

Incorporating Born solvation energy into the three-dimensional Poisson-Nernst-Planck model to study ion selectivity in KcsA K+ channels

NASA Astrophysics Data System (ADS)

Liu, Xuejiao; Lu, Benzhuo

2017-12-01

Potassium channels are much more permeable to potassium than sodium ions, although potassium ions are larger and both carry the same positive charge. This puzzle cannot be solved based on the traditional Poisson-Nernst-Planck (PNP) theory of electrodiffusion because the PNP model treats all ions as point charges, does not incorporate ion size information, and therefore cannot discriminate potassium from sodium ions. The PNP model can qualitatively capture some macroscopic properties of certain channel systems such as current-voltage characteristics, conductance rectification, and inverse membrane potential. However, the traditional PNP model is a continuum mean-field model and has no or underestimates the discrete ion effects, in particular the ion solvation or self-energy (which can be described by Born model). It is known that the dehydration effect (closely related to ion size) is crucial to selective permeation in potassium channels. Therefore, we incorporated Born solvation energy into the PNP model to account for ion hydration and dehydration effects when passing through inhomogeneous dielectric channel environments. A variational approach was adopted to derive a Born-energy-modified PNP (BPNP) model. The model was applied to study a cylindrical nanopore and a realistic KcsA channel, and three-dimensional finite element simulations were performed. The BPNP model can distinguish different ion species by ion radius and predict selectivity for K+ over Na+ in KcsA channels. Furthermore, ion current rectification in the KcsA channel was observed by both the PNP and BPNP models. The I -V curve of the BPNP model for the KcsA channel indicated an inward rectifier effect for K+ (rectification ratio of ˜3 /2 ) but indicated an outward rectifier effect for Na+ (rectification ratio of ˜1 /6 ) .

Mathematical analysis of a power-law form time dependent vector-borne disease transmission model.

PubMed

Sardar, Tridip; Saha, Bapi

2017-06-01

In the last few years, fractional order derivatives have been used in epidemiology to capture the memory phenomena. However, these models do not have proper biological justification in most of the cases and lack a derivation from a stochastic process. In this present manuscript, using theory of a stochastic process, we derived a general time dependent single strain vector borne disease model. It is shown that under certain choice of time dependent transmission kernel this model can be converted into the classical integer order system. When the time-dependent transmission follows a power law form, we showed that the model converted into a vector borne disease model with fractional order transmission. We explicitly derived the disease-free and endemic equilibrium of this new fractional order vector borne disease model. Using mathematical properties of nonlinear Volterra type integral equation it is shown that the unique disease-free state is globally asymptotically stable under certain condition. We define a threshold quantity which is epidemiologically known as the basic reproduction number (R 0 ). It is shown that if R 0 > 1, then the derived fractional order model has a unique endemic equilibrium. We analytically derived the condition for the local stability of the endemic equilibrium. To test the model capability to capture real epidemic, we calibrated our newly proposed model to weekly dengue incidence data of San Juan, Puerto Rico for the time period 30th April 1994 to 23rd April 1995. We estimated several parameters, including the order of the fractional derivative of the proposed model using aforesaid data. It is shown that our proposed fractional order model can nicely capture real epidemic. Copyright © 2017 Elsevier Inc. All rights reserved.

Accuracy assessment of the linear Poisson-Boltzmann equation and reparametrization of the OBC generalized Born model for nucleic acids and nucleic acid-protein complexes.

PubMed

Fogolari, Federico; Corazza, Alessandra; Esposito, Gennaro

2015-04-05

The generalized Born model in the Onufriev, Bashford, and Case (Onufriev et al., Proteins: Struct Funct Genet 2004, 55, 383) implementation has emerged as one of the best compromises between accuracy and speed of computation. For simulations of nucleic acids, however, a number of issues should be addressed: (1) the generalized Born model is based on a linear model and the linearization of the reference Poisson-Boltmann equation may be questioned for highly charged systems as nucleic acids; (2) although much attention has been given to potentials, solvation forces could be much less sensitive to linearization than the potentials; and (3) the accuracy of the Onufriev-Bashford-Case (OBC) model for nucleic acids depends on fine tuning of parameters. Here, we show that the linearization of the Poisson Boltzmann equation has mild effects on computed forces, and that with optimal choice of the OBC model parameters, solvation forces, essential for molecular dynamics simulations, agree well with those computed using the reference Poisson-Boltzmann model. © 2015 Wiley Periodicals, Inc.

On proton excitation of forbidden lines in positive ions

NASA Astrophysics Data System (ADS)

Burgess, Alan; Tully, John A.

2005-08-01

The semi-classical impact parameter approximations used by Bahcall and Wolf and by Bely and Faucher, for proton excitation of electric quadrupole transitions in positive ions, both fail at high energies, giving cross sections which do not fall off correctly as constant/E. This is in contrast with the pioneering example of Seaton for Fe+13 and of Reid and Schwarz for S+3, both of whom achieve the correct functional form, but do not ensure the correct constant of proportionality. By combining the Born and semi-classical approximations one can obtain cross sections which have the full correct behaviour as E → ∞, and hence, rate coefficients which have the correct high temperature behaviour (~C/T1/2 with the correct value of C). We provide a computer program for calculating these. An error in Faucher's derivation of the Born formula is also discussed.

Some design considerations for a satellite-borne magnetograph

NASA Technical Reports Server (NTRS)

Rust, D. M.

1985-01-01

The design criteria for a compact magnetograph that can monitor solar magnetic fields from a free-flying satellite for 5 to 10 years are reviewed. The signal-to-noise ratio that can be obtained with a 10-cm f/10 refractor operated with a Fabry-Perot filter and a solid-state detector array is derived. The telescope measures the longitudinal component of the magnetic field for the entire solar disk in a few minutes at a 20-G threshold and at 3-arcsec resolution. The Fabry-Perot filter has a lithium niobate etalon, which can be tuned electrically and operated at a fixed tilt angle in such a manner that it cancels the solar rotational Doppler shifts in the transmitted spectrum. Principles of operation of various types of polarization modulators are presented, and it is concluded that photoelastic modulators and liquid-crystal devices hold the most promise for use in a satellite-borne magnetograph,

A flexible Bayesian hierarchical model of preterm birth risk among US Hispanic subgroups in relation to maternal nativity and education

PubMed Central

2011-01-01

Background Previous research has documented heterogeneity in the effects of maternal education on adverse birth outcomes by nativity and Hispanic subgroup in the United States. In this article, we considered the risk of preterm birth (PTB) using 9 years of vital statistics birth data from New York City. We employed finer categorizations of exposure than used previously and estimated the risk dose-response across the range of education by nativity and ethnicity. Methods Using Bayesian random effects logistic regression models with restricted quadratic spline terms for years of completed maternal education, we calculated and plotted the estimated posterior probabilities of PTB (gestational age < 37 weeks) for each year of education by ethnic and nativity subgroups adjusted for only maternal age, as well as with more extensive covariate adjustments. We then estimated the posterior risk difference between native and foreign born mothers by ethnicity over the continuous range of education exposures. Results The risk of PTB varied substantially by education, nativity and ethnicity. Native born groups showed higher absolute risk of PTB and declining risk associated with higher levels of education beyond about 10 years, as did foreign-born Puerto Ricans. For most other foreign born groups, however, risk of PTB was flatter across the education range. For Mexicans, Central Americans, Dominicans, South Americans and "Others", the protective effect of foreign birth diminished progressively across the educational range. Only for Puerto Ricans was there no nativity advantage for the foreign born, although small numbers of foreign born Cubans limited precision of estimates for that group. Conclusions Using flexible Bayesian regression models with random effects allowed us to estimate absolute risks without strong modeling assumptions. Risk comparisons for any sub-groups at any exposure level were simple to calculate. Shrinkage of posterior estimates through the use of random effects allowed for finer categorization of exposures without restricting joint effects to follow a fixed parametric scale. Although foreign born Hispanic women with the least education appeared to generally have low risk, this seems likely to be a marker for unmeasured environmental and behavioral factors, rather than a causally protective effect of low education itself. PMID:21504612

A flexible Bayesian hierarchical model of preterm birth risk among US Hispanic subgroups in relation to maternal nativity and education.

PubMed

Kaufman, Jay S; MacLehose, Richard F; Torrone, Elizabeth A; Savitz, David A

2011-04-19

Previous research has documented heterogeneity in the effects of maternal education on adverse birth outcomes by nativity and Hispanic subgroup in the United States. In this article, we considered the risk of preterm birth (PTB) using 9 years of vital statistics birth data from New York City. We employed finer categorizations of exposure than used previously and estimated the risk dose-response across the range of education by nativity and ethnicity. Using Bayesian random effects logistic regression models with restricted quadratic spline terms for years of completed maternal education, we calculated and plotted the estimated posterior probabilities of PTB (gestational age < 37 weeks) for each year of education by ethnic and nativity subgroups adjusted for only maternal age, as well as with more extensive covariate adjustments. We then estimated the posterior risk difference between native and foreign born mothers by ethnicity over the continuous range of education exposures. The risk of PTB varied substantially by education, nativity and ethnicity. Native born groups showed higher absolute risk of PTB and declining risk associated with higher levels of education beyond about 10 years, as did foreign-born Puerto Ricans. For most other foreign born groups, however, risk of PTB was flatter across the education range. For Mexicans, Central Americans, Dominicans, South Americans and "Others", the protective effect of foreign birth diminished progressively across the educational range. Only for Puerto Ricans was there no nativity advantage for the foreign born, although small numbers of foreign born Cubans limited precision of estimates for that group. Using flexible Bayesian regression models with random effects allowed us to estimate absolute risks without strong modeling assumptions. Risk comparisons for any sub-groups at any exposure level were simple to calculate. Shrinkage of posterior estimates through the use of random effects allowed for finer categorization of exposures without restricting joint effects to follow a fixed parametric scale. Although foreign born Hispanic women with the least education appeared to generally have low risk, this seems likely to be a marker for unmeasured environmental and behavioral factors, rather than a causally protective effect of low education itself.

Tracking reliability for space cabin-borne equipment in development by Crow model.

PubMed

Chen, J D; Jiao, S J; Sun, H L

2001-12-01

Objective. To study and track the reliability growth of manned spaceflight cabin-borne equipment in the course of its development. Method. A new technique of reliability growth estimation and prediction, which is composed of the Crow model and test data conversion (TDC) method was used. Result. The estimation and prediction value of the reliability growth conformed to its expectations. Conclusion. The method could dynamically estimate and predict the reliability of the equipment by making full use of various test information in the course of its development. It offered not only a possibility of tracking the equipment reliability growth, but also the reference for quality control in manned spaceflight cabin-borne equipment design and development process.

Term infants born at home in Peru are less likely to be hospitalised in the neonatal period than those born in hospital.

PubMed

Lavin, Tina; Preen, David B

2017-08-01

More than 50% of women worldwide give birth at home, but little is known about home birth and subsequent neonatal hospitalisation. The objective of the study was to investigate home birth and neonatal hospitalisation of term neonates in Peru. The relationship between birth setting [home - with or without skilled birth attendant (SBA), health centre, hospital] and neonatal hospitalisation (n = 1656) and incubator care (n = 1651) was investigated using data from the 2002 Young Lives Study. Infants were sampled from 20 sentinel sites across Peru. At each sentinel site 100 households with children aged 6-18 months were randomly sampled (therefore the sample only captured children surviving to 6 months of age). Multivariate regression modelling was used with models adjusted for a range of demographic and clinical factors. After adjustment, the odds of hospitalisation were lower in neonates born at home (with SBA OR 0.20, 95% CI 0.0-0.8, p = 0.021; without SBA OR = 0.4, 95% CI 0.2-0.7, p = 0.002) than in those born in hospital. Socio-demographic factors such as ethnicity, rural living, education, socio-economic status and access to transport did not influence neonatal hospitalisation, time in hospital, incubator care or time under incubator care. Neonates born at home were less likely to be hospitalised after birth owing to neonatal morbidity than neonates born in hospital. It is unclear whether this finding reflects poorer accessibility to hospital care for neonates born at home, or if neonates born at home required hospitalisation less frequently than neonates born in hospital owing to lower neonatal morbidity or other factors such as lower rates of medical intervention for home births. Further research is needed to explore the underlying mechanisms of these findings.

Mortality among US-born and immigrant Hispanics in the US: effects of nativity, duration of residence, and age at immigration.

PubMed

Holmes, Julia S; Driscoll, Anne K; Heron, Melonie

2015-07-01

We examined the effects of duration of residence and age at immigration on mortality among US-born and foreign-born Hispanics aged 25 and older. We analyzed the National Health Interview Survey-National Death Index linked files from 1997-2009 with mortality follow-up through 2011. We used Cox proportional hazard models to examine the effects of duration of US residence and age at immigration on mortality for US-born and foreign-born Hispanics, controlling for various demographic, socioeconomic and health factors. Age at immigration included 4 age groups: <18, 18-24, 25-34, and 35+ years. Duration of residence was 0-15 and >15 years. We observed a mortality advantage among Hispanic immigrants compared to US-born Hispanics only for those who had come to the US after age 24 regardless of how long they had lived in the US. Hispanics who immigrated as youths (<18) did not differ from US-born Hispanics on mortality despite duration of residence. Findings suggest that age at immigration, rather than duration of residence, drives differences in mortality between Hispanic immigrants and the US-born Hispanic population.

[Louse-borne typhus potential and new technologies in prediction of epidemic louse-borne typhus outburst].

PubMed

Boev, B V; Lobanov, A V; Khudobin, V V

2008-01-01

Features of louse-borne typhus in Russia in the middle of 20th century are considered. Study of the infection source, blood serum in patient after epidemic louse-borne typhus (ELBT) and agent (louse) was performed on territory with high morbidity of pediculosis and ELBT in the years of 2nd world war. New materials of seroimmunological examinations are represented. Priority data of lice morphology based on morphometrical data of lice, collected in Russia and world collection in Berlin are shown. Methods of ELBT prediction are given, special attention is paid to development of mathematic prognostic models based on new technologies.

Design and Evaluation of a Balloon-Borne Electric Field Sensor

DTIC Science & Technology

1976-10-18

on a Lume A? A.3 Total Induced Charge vs, Orientation AB APPENDIX B ELEMflUICS PACAE B.l Electrometer Amplifier BI B.Z2 Charge Aplifier Bl B.3...properties change with height? 3) How strongly are fields mapped between the ground and the ionosphere? Because of its ability to make accurate profile...then each conductor should reach the potential of the average atmospheric potential surrounding the probes. These probes probably are of limited use

Investigations in the ionosphere on Kosmos 378. IV. Structure of regions where electrons with energies 0. 5-12 keV and their convection are recorded

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khokhlov, M.Z.

1975-01-01

The position of regions where electron fluxes were recorded in November 1970 is analyzed from the data of satellite-borne charged particle analyzers. These regions are located at invariant latitudes ..lambda.. > 65/sup 0/ under geomagnetically quiet conditions and separate into low- and high-latitude zones. The electric drift speed in the high-latitude zone is estimated. 37 references.

Perceptions of Prostate Cancer Fatalism and Screening Behavior Between United States-Born and Caribbean-Born Black Males

PubMed Central

Cobran, Ewan K.; Wutoh, Anthony K.; Lee, Euni; Odedina, Folakemi T.; Ragin, Camille; Aiken, William; Godley, Paul A.

2013-01-01

Cancer fatalism is believed to be a major barrier for cancer screening in Black males. Therefore, the purpose of this study was to compare perceptions of prostate cancer (CaP) fatalism and predictors of CaP screening with Prostate Specific Antigen (PSA) testing between U.S.-born and Caribbean-born Black males. The Powe Fatalism Inventory and the Personal Integrative Model of CaP Disparity Survey were used to collect the following data from males in South Florida. Multivariate logistic regression models were constructed to examine the statistically significant predictors of CaP screening. A total of 211 U.S.-born and Caribbean-born Black males between ages 39–75 were recruited. Nativity was not a significant predictor of CaP screening with PSA testing within the last year (Odds ratio [OR] = 0.80, 95 % confidence interval [CI] = 0.26, 2.48, p = 0.70). Overall, higher levels of CaP fatalism were not a significant predictor of CaP screening with PSA testing within the last year (OR = 1.37, 95 % CI = 0.48, 3.91, p = 0.56). The study results suggest that nativity did not influence CaP screening with PSA testing. However, further studies are needed to evaluate the association between CaP screening behavior and levels of CaP fatalism. PMID:23576029

Thermodynamics of a Higher Dimensional Noncommutative Inspired Anti-de Sitter-Einstein-Born-Infeld Black Hole

NASA Astrophysics Data System (ADS)

González, Angélica; Linares, Román; Maceda, Marco; Sánchez-Santos, Oscar

2018-04-01

We analyze noncommutative deformations of a higher dimensional anti-de Sitter-Einstein-Born-Infeld black hole. Two models based on noncommutative inspired distributions of mass and charge are discussed and their thermodynamical properties such as the equation of state are explicitly calculated. In the (3 + 1)-dimensional case the Gibbs energy function of each model is used to discuss the presence of phase transitions.

Electrostatic Solvation Energy for Two Oppositely Charged Ions in a Solvated Protein System: Salt Bridges Can Stabilize Proteins

PubMed Central

Gong, Haipeng; Freed, Karl F.

2010-01-01

Abstract Born-type electrostatic continuum methods have been an indispensable ingredient in a variety of implicit-solvent methods that reduce computational effort by orders of magnitude compared to explicit-solvent MD simulations and thus enable treatment using larger systems and/or longer times. An analysis of the limitations and failures of the Born approaches serves as a guide for fundamental improvements without diminishing the importance of prior works. One of the major limitations of the Born theory is the lack of a liquidlike description of the response of solvent dipoles to the electrostatic field of the solute and the changes therein, a feature contained in the continuum Langevin-Debye (LD) model applied here to investigate how Coulombic interactions depend on the location of charges relative to the protein/water boundary. This physically more realistic LD model is applied to study the stability of salt bridges. When compared head to head using the same (independently measurable) physical parameters (radii, dielectric constants, etc.), the LD model is in good agreement with observations, whereas the Born model is grossly in error. Our calculations also suggest that a salt bridge on the protein's surface can be stabilizing when the charge separation is ≤4 Å. PMID:20141761

Three-Dimensional Finite Element Analysis of Stress Distribution and Displacement of the Maxilla Following Surgically Assisted Rapid Maxillary Expansion with Tooth- and Bone-Borne Devices.

PubMed

Dalband, Mohsen; Kashani, Jamal; Hashemzehi, Hadi

2015-04-01

The aim of this study was to investigate the displacement and stress distribution during surgically assisted rapid maxillary expansion under different surgical conditions with tooth- and bone-borne devices. Three-dimensional (3D) finite element model of a maxilla was constructed and an expansion force of 100 N was applied to the left and right molars and premolars with tooth-borne devices and the left and right of mid-palatal sutures at the first molar level with bone-borne devices. Five computer-aided design (CAD) models were simulated as follows and surgical procedures were used: G1: control group (without surgery); G2: Le Fort I osteotomy; G3: Le Fort I osteotomy and para-median osteotomy; G4: Le Fort I osteotomy and pterygomaxillary separation; and G5: Le Fort I osteotomy, para-median osteotomy, and pterygomaxillary separation. Maxillary displacement showed a gradual increase from G1 to G5 in all three planes of space, indicating that Le Fort I osteotomy combined with para-median osteotomy and pterygomaxillary separation produced the greatest displacement of the maxilla with both bone- and tooth-borne devices. Surgical relief and bone-borne devices resulted in significantly reduced stress on anchored teeth. Combination of Le Fort I and para-median osteotomy with pterygomaxillary separation seems to be an effective procedure for increasing maxillary expansion, and excessive stress side effects are lowered around the anchored teeth with the use of bone-borne devices.

Ross, macdonald, and a theory for the dynamics and control of mosquito-transmitted pathogens.

PubMed

Smith, David L; Battle, Katherine E; Hay, Simon I; Barker, Christopher M; Scott, Thomas W; McKenzie, F Ellis

2012-01-01

Ronald Ross and George Macdonald are credited with developing a mathematical model of mosquito-borne pathogen transmission. A systematic historical review suggests that several mathematicians and scientists contributed to development of the Ross-Macdonald model over a period of 70 years. Ross developed two different mathematical models, Macdonald a third, and various "Ross-Macdonald" mathematical models exist. Ross-Macdonald models are best defined by a consensus set of assumptions. The mathematical model is just one part of a theory for the dynamics and control of mosquito-transmitted pathogens that also includes epidemiological and entomological concepts and metrics for measuring transmission. All the basic elements of the theory had fallen into place by the end of the Global Malaria Eradication Programme (GMEP, 1955-1969) with the concept of vectorial capacity, methods for measuring key components of transmission by mosquitoes, and a quantitative theory of vector control. The Ross-Macdonald theory has since played a central role in development of research on mosquito-borne pathogen transmission and the development of strategies for mosquito-borne disease prevention.

Ross, Macdonald, and a Theory for the Dynamics and Control of Mosquito-Transmitted Pathogens

PubMed Central

Smith, David L.; Battle, Katherine E.; Hay, Simon I.; Barker, Christopher M.; Scott, Thomas W.; McKenzie, F. Ellis

2012-01-01

Ronald Ross and George Macdonald are credited with developing a mathematical model of mosquito-borne pathogen transmission. A systematic historical review suggests that several mathematicians and scientists contributed to development of the Ross-Macdonald model over a period of 70 years. Ross developed two different mathematical models, Macdonald a third, and various “Ross-Macdonald” mathematical models exist. Ross-Macdonald models are best defined by a consensus set of assumptions. The mathematical model is just one part of a theory for the dynamics and control of mosquito-transmitted pathogens that also includes epidemiological and entomological concepts and metrics for measuring transmission. All the basic elements of the theory had fallen into place by the end of the Global Malaria Eradication Programme (GMEP, 1955–1969) with the concept of vectorial capacity, methods for measuring key components of transmission by mosquitoes, and a quantitative theory of vector control. The Ross-Macdonald theory has since played a central role in development of research on mosquito-borne pathogen transmission and the development of strategies for mosquito-borne disease prevention. PMID:22496640

Beyond Born-Mayer: Improved models for short-range repulsion in ab initio force fields

DOE PAGES

Van Vleet, Mary J.; Misquitta, Alston J.; Stone, Anthony J.; ...

2016-06-23

Short-range repulsion within inter-molecular force fields is conventionally described by either Lennard-Jones or Born-Mayer forms. Despite their widespread use, these simple functional forms are often unable to describe the interaction energy accurately over a broad range of inter-molecular distances, thus creating challenges in the development of ab initio force fields and potentially leading to decreased accuracy and transferability. Herein, we derive a novel short-range functional form based on a simple Slater-like model of overlapping atomic densities and an iterated stockholder atom (ISA) partitioning of the molecular electron density. We demonstrate that this Slater-ISA methodology yields a more accurate, transferable, andmore » robust description of the short-range interactions at minimal additional computational cost compared to standard Lennard-Jones or Born-Mayer approaches. Lastly, we show how this methodology can be adapted to yield the standard Born-Mayer functional form while still retaining many of the advantages of the Slater-ISA approach.« less

Retracing the Evolutionary Path that Led to Flea-borne Transmission of Yersinia pestis

PubMed Central

Sun, Yi-Cheng; Jarrett, Clayton O.; Bosio, Christopher F.; Hinnebusch, B. Joseph

2014-01-01

Summary Yersinia pestis is an arthropod-borne bacterial pathogen that evolved recently from Yersinia pseudotuberculosis, an enteric pathogen transmitted via the fecal-oral route. This radical ecological transition can be attributed to a few discrete genetic changes from a still-extant recent ancestor, thus providing a tractable case study in pathogen evolution and emergence. Here, we determined the precise genetic and mechanistic basis of the evolutionary adaptation of Y. pestis to flea-borne transmission. Remarkably, only four minor changes in the bacterial progenitor, representing one gene gain and three gene losses, enabled transmission by flea vectors. All three loss-of-function mutations enhanced c-di-GMP-mediated bacterial biofilm formation in the flea foregut that greatly increased transmissibility. Our results suggest a step-wise evolutionary model in which Y. pestis emerged as a flea-borne clone, with each genetic change incrementally reinforcing the transmission cycle. The model conforms well to the ecological theory of adaptive radiation. PMID:24832452

Retracing the evolutionary path that led to flea-borne transmission of Yersinia pestis.

PubMed

Sun, Yi-Cheng; Jarrett, Clayton O; Bosio, Christopher F; Hinnebusch, B Joseph

2014-05-14

Yersinia pestis is an arthropod-borne bacterial pathogen that evolved recently from Yersinia pseudotuberculosis, an enteric pathogen transmitted via the fecal-oral route. This radical ecological transition can be attributed to a few discrete genetic changes from a still-extant recent ancestor, thus providing a tractable case study in pathogen evolution and emergence. Here, we determined the genetic and mechanistic basis of the evolutionary adaptation of Y. pestis to flea-borne transmission. Remarkably, only four minor changes in the bacterial progenitor, representing one gene gain and three gene losses, enabled transmission by flea vectors. All three loss-of-function mutations enhanced cyclic-di-GMP-mediated bacterial biofilm formation in the flea foregut, which greatly increased transmissibility. Our results suggest a step-wise evolutionary model in which Y. pestis emerged as a flea-borne clone, with each genetic change incrementally reinforcing the transmission cycle. The model conforms well to the ecological theory of adaptive radiation. Copyright © 2014 Elsevier Inc. All rights reserved.

Prostate and Colorectal Cancer Screening Uptake among US and Foreign-Born Males: Evidence from the 2015 NHIS Survey.

PubMed

Ilunga Tshiswaka, Daudet; Donley, Tiffany; Okafor, Anthony; Memiah, Peter; Mbizo, Justice

2017-06-01

Research suggests that prostate and colorectal cancers disproportionately affect men in the US, but little is known about the determinants of prostate-specific antigen (PSA) and colorectal cancer (CRC) screening uptake among US and foreign-born males. The purpose of this study was to investigate what factors influence prostate and colorectal cancer screening uptake among US-native born and foreign-born men. Using the 2015 National Health Interview Survey, we conducted bivariate and multivariate analyses to highlight factors associated with the uptake of prostate and colorectal cancer screening among US-native born and foreign-born men. The sample size consisted of 5651 men respondents, with the mean age of 59.7 years (SD = 12.1). Of these, more than two-fifths (42%) were aged 50-64 years old. With respect to race/ethnicity, the sample was predominantly non-Hispanic Whites (65.5%), 863 (15.6%) Hispanics, and 710 (12.4%) Blacks. Our analysis found higher rates of both US-born and foreign-born men aged 65 years or older, who had either a PSA or CRC screening tests than those aged <65 years. Results of the general multivariate model suggest that men under 50 years old, US-born and foreign-born alike, are statistically significantly less likely to have prostate or colorectal cancer screenings than men aged 65 years or above. This study highlights the influencing factors that encourage or discourage PSA and CRC screening uptake between US-native born and foreign-born men. The results of this inquiry provide an evidence-based blueprint for policymakers and interventionists seeking to address prostate and colorectal cancer among men.

The Influence Analysis of the Rainfall Meteorological Conditions on the Operation of the Balloon Borne Radar in Plateau

NASA Astrophysics Data System (ADS)

Li, Qiong; Geng, Fangzhi

2018-03-01

Based on the characteristics of complex terrain and different seasons’ weather in Qinghai Tibet Plateau, through statistic the daily rainfall that from 2002 to 2012, nearly 11 years, by Bomi meteorological station, Bomi area rainfall forecast model is established, and which can provide the basis forecasting for dangerous weather warning system on the balloon borne radar in the next step, to protect the balloon borne radar equipment’s safety work and combat effectiveness.

Calculation of Protein Heat Capacity from Replica-Exchange Molecular Dynamics Simulations with Different Implicit Solvent Models

DTIC Science & Technology

2008-10-30

rigorous Poisson-based methods generally apply a Lee-Richards mo- lecular surface.9 This surface is considered the de facto description for continuum...definition and calculation of the Born radii. To evaluate the Born radii, two approximations are invoked. The first is the Coulomb field approximation (CFA...energy term, and depending on the particular GB formulation, higher-order non- Coulomb correction terms may be added to the Born radii to account for the

A global network for the control of snail-borne disease using satellite surveillance and geographic information systems.

PubMed

Malone, J B; Bergquist, N R; Huh, O K; Bavia, M E; Bernardi, M; El Bahy, M M; Fuentes, M V; Kristensen, T K; McCarroll, J C; Yilma, J M; Zhou, X N

2001-04-27

At a team residency sponsored by the Rockefeller Foundation in Bellagio, Italy, 10-14 April 2000 an organizational plan was conceived to create a global network of collaborating health workers and earth scientists dedicated to the development of computer-based models that can be used for improved control programs for schistosomiasis and other snail-borne diseases of medical and veterinary importance. The models will be assembled using GIS methods, global climate model data, sensor data from earth observing satellites, disease prevalence data, the distribution and abundance of snail hosts, and digital maps of key environmental factors that affect development and propagation of snail-borne disease agents. A work plan was developed for research collaboration and data sharing, recruitment of new contributing researchers, and means of access of other medical scientists and national control program managers to GIS models that may be used for more effective control of snail-borne disease. Agreement was reached on the use of compatible GIS formats, software, methods and data resources, including the definition of a 'minimum medical database' to enable seamless incorporation of results from each regional GIS project into a global model. The collaboration plan calls for linking a 'central resource group' at the World Health Organization, the Food and Agriculture Organization, Louisiana State University and the Danish Bilharziasis Laboratory with regional GIS networks to be initiated in Eastern Africa, Southern Africa, West Africa, Latin America and Southern Asia. An Internet site, www.gnosisGIS.org, (GIS Network On Snail-borne Infections with special reference to Schistosomiasis), has been initiated to allow interaction of team members as a 'virtual research group'. When completed, the site will point users to a toolbox of common resources resident on computers at member organizations, provide assistance on routine use of GIS health maps in selected national disease control programs and provide a forum for development of GIS models to predict the health impacts of water development projects and climate variation.

A differential equation for the Generalized Born radii.

PubMed

Fogolari, Federico; Corazza, Alessandra; Esposito, Gennaro

2013-06-28

The Generalized Born (GB) model offers a convenient way of representing electrostatics in complex macromolecules like proteins or nucleic acids. The computation of atomic GB radii is currently performed by different non-local approaches involving volume or surface integrals. Here we obtain a non-linear second-order partial differential equation for the Generalized Born radius, which may be solved using local iterative algorithms. The equation is derived under the assumption that the usual GB approximation to the reaction field obeys Laplace's equation. The equation admits as particular solutions the correct GB radii for the sphere and the plane. The tests performed on a set of 55 different proteins show an overall agreement with other reference GB models and "perfect" Poisson-Boltzmann based values.

Social development of children born very preterm: a systematic review.

PubMed

Ritchie, Kirsten; Bora, Samudragupta; Woodward, Lianne J

2015-10-01

To review systematically studies examining the development of social competence in children born very preterm (VPT) (gestation <33 wks) and identify neonatal and family predictors. Peer-reviewed original articles were extracted from PubMed and PsycINFO following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Selection criteria included children born VPT and comparison children born at term, sample born after 1990, and children assessed between 0 and 17 years on at least one measure of social competence spanning social adjustment, performance, and/or social skills. Twenty-three studies were included. Seven focused on social competence and another 16 examined social competence within a range of outcomes. Study quality was low. Limitations included reliance on single informant data, cross-sectional measurement, use of brief screening tools, absence of child or peer report, and no conceptual model. In terms of social adjustment, 16 out of 21 studies found children born VPT had more peer problems and social withdrawal. Findings of social performance were mixed, with some studies suggesting differences in prosocial behavior (4/14) and others not. Social skills were assessed in four studies and showed children born VPT had poorer skills than children born at term. Predictors of social competence included gestational age, neonatal brain abnormalities, and family socio-economic status. Children born VPT have poorer social competence. These difficulties emerge early and persist throughout childhood. © 2015 Mac Keith Press.

Kinklike structures in models of the Dirac-Born-Infeld type

NASA Astrophysics Data System (ADS)

Bazeia, D.; Lima, Elisama E. M.; Losano, L.

2018-01-01

The present work investigates several models of a single real scalar field, engendering kinetic term of the Dirac-Born- Infeld type. Such theories introduce nonlinearities to the kinetic part of the Lagrangian, which presents a square root restricting the field evolution and including additional powers in derivatives of the scalar field, controlled by a real parameter. In order to obtain topological solutions analytically, we propose a first-order framework that simplifies the equation of motion ensuring solutions that are linearly stable. This is implemented using the deformation method, and we introduce examples presenting two categories of potentials, one having polynomial interactions and the other with nonpolynomial interactions. We also explore how the Dirac-Born-Infeld kinetic term affects the properties of the solutions. In particular, we note that the kinklike solutions are similar to the ones obtained through models with standard kinetic term and canonical potential, but their energy densities and stability potentials vary according to the parameter introduced to control the new models.

Coherent states, quantum gravity, and the Born-Oppenheimer approximation. I. General considerations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stottmeister, Alexander, E-mail: alexander.stottmeister@gravity.fau.de; Thiemann, Thomas, E-mail: thomas.thiemann@gravity.fau.de

2016-06-15

This article, as the first of three, aims at establishing the (time-dependent) Born-Oppenheimer approximation, in the sense of space adiabatic perturbation theory, for quantum systems constructed by techniques of the loop quantum gravity framework, especially the canonical formulation of the latter. The analysis presented here fits into a rather general framework and offers a solution to the problem of applying the usual Born-Oppenheimer ansatz for molecular (or structurally analogous) systems to more general quantum systems (e.g., spin-orbit models) by means of space adiabatic perturbation theory. The proposed solution is applied to a simple, finite dimensional model of interacting spin systems,more » which serves as a non-trivial, minimal model of the aforesaid problem. Furthermore, it is explained how the content of this article and its companion affect the possible extraction of quantum field theory on curved spacetime from loop quantum gravity (including matter fields).« less

Black hole solutions in mimetic Born-Infeld gravity

NASA Astrophysics Data System (ADS)

Chen, Che-Yu; Bouhmadi-López, Mariam; Chen, Pisin

2018-01-01

The vacuum, static, and spherically symmetric solutions in the mimetic Born-Infeld gravity are studied. The mimetic Born-Infeld gravity is a reformulation of the Eddington-inspired-Born-Infeld (EiBI) model under the mimetic approach. Due to the mimetic field, the theory contains non-trivial vacuum solutions different from those in Einstein gravity. We find that with the existence of the mimetic field, the spacelike singularity inside a Schwarzschild black hole could be altered to a lightlike singularity, even though the curvature invariants still diverge at the singularity. Furthermore, in this case, the maximal proper time for a timelike radially-infalling observer to reach the singularity is found to be infinite.

Black hole solutions in mimetic Born-Infeld gravity.

PubMed

Chen, Che-Yu; Bouhmadi-López, Mariam; Chen, Pisin

2018-01-01

The vacuum, static, and spherically symmetric solutions in the mimetic Born-Infeld gravity are studied. The mimetic Born-Infeld gravity is a reformulation of the Eddington-inspired-Born-Infeld (EiBI) model under the mimetic approach. Due to the mimetic field, the theory contains non-trivial vacuum solutions different from those in Einstein gravity. We find that with the existence of the mimetic field, the spacelike singularity inside a Schwarzschild black hole could be altered to a lightlike singularity, even though the curvature invariants still diverge at the singularity. Furthermore, in this case, the maximal proper time for a timelike radially-infalling observer to reach the singularity is found to be infinite.

Second-order Born calculation of coplanar symmetric (e, 2e) process on Mg

NASA Astrophysics Data System (ADS)

Zhang, Yong-Zhi; Wang, Yang; Zhou, Ya-Jun

2014-06-01

The second-order distorted wave Born approximation (DWBA) method is employed to investigate the triple differential cross sections (TDCS) of coplanar doubly symmetric (e, 2e) collisions for magnesium at excess energies of 6 eV-20 eV. Comparing with the standard first-order DWBA calculations, the inclusion of the second-order Born term in the scattering amplitude improves the degree of agreement with experiments, especially for backward scattering region of TDCS. This indicates that the present second-order Born term is capable to give a reasonable correction to DWBA model in studying coplanar symmetric (e, 2e) problems of two-valence-electron target in low energy range.

Black hole solutions in mimetic Born-Infeld gravity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Che-Yu; Bouhmadi-López, Mariam; Chen, Pisin

The vacuum, static, and spherically symmetric solutions in the mimetic Born-Infeld gravity are studied. The mimetic Born-Infeld gravity is a reformulation of the Eddington-inspired-Born-Infeld (EiBI) model under the mimetic approach. Due to the mimetic field, the theory contains non-trivial vacuum solutions different from those in Einstein gravity. Here, we find that with the existence of the mimetic field, the spacelike singularity inside a Schwarzschild black hole could be altered to a lightlike singularity, even though the curvature invariants still diverge at the singularity. Furthermore, in this case, the maximal proper time for a timelike radially-infalling observer to reach the singularitymore » is found to be infinite.« less

Black hole solutions in mimetic Born-Infeld gravity

DOE PAGES

Chen, Che-Yu; Bouhmadi-López, Mariam; Chen, Pisin

2018-01-23

The vacuum, static, and spherically symmetric solutions in the mimetic Born-Infeld gravity are studied. The mimetic Born-Infeld gravity is a reformulation of the Eddington-inspired-Born-Infeld (EiBI) model under the mimetic approach. Due to the mimetic field, the theory contains non-trivial vacuum solutions different from those in Einstein gravity. Here, we find that with the existence of the mimetic field, the spacelike singularity inside a Schwarzschild black hole could be altered to a lightlike singularity, even though the curvature invariants still diverge at the singularity. Furthermore, in this case, the maximal proper time for a timelike radially-infalling observer to reach the singularitymore » is found to be infinite.« less

Giovanni Aldini: from animal electricity to human brain stimulation.

PubMed

Parent, André

2004-11-01

Two hundred years ago, Giovanni Aldini published a highly influential book that reported experiments in which the principles of Luigi Galvani (animal electricity) and Alessandro Volta (bimetallic electricity) were used together for the first time. Aldini was born in Bologna in 1762 and graduated in physics at the University of his native town in 1782. As nephew and assistant of Galvani, he actively participated in a series of crucial experiments with frog's muscles that led to the idea that electricity was the long-sought vital force coursing from brain to muscles. Aldini became professor of experimental physics at the University of Bologna in 1798. He traveled extensively throughout Europe, spending much time defending the concept of his discreet uncle against the incessant attacks of Volta, who did not believe in animal electricity. Aldini used Volta's bimetallic pile to apply electric current to dismembered bodies of animals and humans; these spectacular galvanic reanimation experiments made a strong and enduring impression on his contemporaries. Aldini also treated patients with personality disorders and reported complete rehabilitation following transcranial administration of electric current. Aldini's work laid the ground for the development of various forms of electrotherapy that were heavily used later in the 19th century. Even today, deep brain stimulation, a procedure currently employed to relieve patients with motor or behavioral disorders, owes much to Aldini and galvanism. In recognition of his merits, Aldini was made a knight of the Iron Crown and a councillor of state at Milan, where he died in 1834.

Modelling the Wind-Borne Spread of Highly Pathogenic Avian Influenza Virus between Farms

PubMed Central

Ssematimba, Amos; Hagenaars, Thomas J.; de Jong, Mart C. M.

2012-01-01

A quantitative understanding of the spread of contaminated farm dust between locations is a prerequisite for obtaining much-needed insight into one of the possible mechanisms of disease spread between farms. Here, we develop a model to calculate the quantity of contaminated farm-dust particles deposited at various locations downwind of a source farm and apply the model to assess the possible contribution of the wind-borne route to the transmission of Highly Pathogenic Avian Influenza virus (HPAI) during the 2003 epidemic in the Netherlands. The model is obtained from a Gaussian Plume Model by incorporating the dust deposition process, pathogen decay, and a model for the infection process on exposed farms. Using poultry- and avian influenza-specific parameter values we calculate the distance-dependent probability of between-farm transmission by this route. A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 epidemic reveals that the wind-borne route alone is insufficient to explain the observations although it could contribute substantially to the spread over short distance ranges, for example, explaining 24% of the transmission over distances up to 25 km. PMID:22348042

Modelling the wind-borne spread of highly pathogenic avian influenza virus between farms.

PubMed

Ssematimba, Amos; Hagenaars, Thomas J; de Jong, Mart C M

2012-01-01

A quantitative understanding of the spread of contaminated farm dust between locations is a prerequisite for obtaining much-needed insight into one of the possible mechanisms of disease spread between farms. Here, we develop a model to calculate the quantity of contaminated farm-dust particles deposited at various locations downwind of a source farm and apply the model to assess the possible contribution of the wind-borne route to the transmission of Highly Pathogenic Avian Influenza virus (HPAI) during the 2003 epidemic in the Netherlands. The model is obtained from a Gaussian Plume Model by incorporating the dust deposition process, pathogen decay, and a model for the infection process on exposed farms. Using poultry- and avian influenza-specific parameter values we calculate the distance-dependent probability of between-farm transmission by this route. A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 epidemic reveals that the wind-borne route alone is insufficient to explain the observations although it could contribute substantially to the spread over short distance ranges, for example, explaining 24% of the transmission over distances up to 25 km.

Fourteen babies born after round spermatid injection into human oocytes

PubMed Central

Tanaka, Atsushi; Nagayoshi, Motoi; Takemoto, Youichi; Tanaka, Izumi; Kusunoki, Hiroshi; Watanabe, Seiji; Kuroda, Keiji; Takeda, Satoru; Ito, Masahiko; Yanagimachi, Ryuzo

2015-01-01

During the human in vitro fertilization procedure in the assisted reproductive technology, intracytoplasmic sperm injection is routinely used to inject a spermatozoon or a less mature elongating spermatid into the oocyte. In some infertile men, round spermatids (haploid male germ cells that have completed meiosis) are the most mature cells visible during testicular biopsy. The microsurgical injection of a round spermatid into an oocyte as a substitute is commonly referred to as round spermatid injection (ROSI). Currently, human ROSI is considered a very inefficient procedure and of no clinical value. Herein, we report the birth and development of 14 children born to 12 women following ROSI of 734 oocytes previously activated by an electric current. The round spermatids came from men who had been diagnosed as not having spermatozoa or elongated spermatids by andrologists at other hospitals after a first Micro-TESE. A key to our success was our ability to identify round spermatids accurately before oocyte injection. As of today, all children born after ROSI in our clinic are without any unusual physical, mental, or epigenetic problems. Thus, for men whose germ cells are unable to develop beyond the round spermatid stage, ROSI can, as a last resort, enable them to have their own genetic offspring. PMID:26575628

Fourteen babies born after round spermatid injection into human oocytes.

PubMed

Tanaka, Atsushi; Nagayoshi, Motoi; Takemoto, Youichi; Tanaka, Izumi; Kusunoki, Hiroshi; Watanabe, Seiji; Kuroda, Keiji; Takeda, Satoru; Ito, Masahiko; Yanagimachi, Ryuzo

2015-11-24

During the human in vitro fertilization procedure in the assisted reproductive technology, intracytoplasmic sperm injection is routinely used to inject a spermatozoon or a less mature elongating spermatid into the oocyte. In some infertile men, round spermatids (haploid male germ cells that have completed meiosis) are the most mature cells visible during testicular biopsy. The microsurgical injection of a round spermatid into an oocyte as a substitute is commonly referred to as round spermatid injection (ROSI). Currently, human ROSI is considered a very inefficient procedure and of no clinical value. Herein, we report the birth and development of 14 children born to 12 women following ROSI of 734 oocytes previously activated by an electric current. The round spermatids came from men who had been diagnosed as not having spermatozoa or elongated spermatids by andrologists at other hospitals after a first Micro-TESE. A key to our success was our ability to identify round spermatids accurately before oocyte injection. As of today, all children born after ROSI in our clinic are without any unusual physical, mental, or epigenetic problems. Thus, for men whose germ cells are unable to develop beyond the round spermatid stage, ROSI can, as a last resort, enable them to have their own genetic offspring.

Investigation of Radio Frequency Discharges and Langmuir Probe Diagnostic Methods in a Fast Flowing Electronegative Background Gas

DTIC Science & Technology

2007-12-01

Pinhero and others, 1998). The Air Force is currently developing the Electric Chemical Oxygen Iodine Laser (ElectriCOIL) system to replace the liquid...chemistry generator currently used in the Air Borne Laser (ABL) system (Zimmerman and others, 2003). The ElectriCOIL system produces in a radio...convected downstream is critical to improving the performance of the ABL system . The use of a second non-self sustained discharge operating at a lower

Relative permittivity in the electrical double layer from nonlinear optics

NASA Astrophysics Data System (ADS)

Boamah, Mavis D.; Ohno, Paul E.; Geiger, Franz M.; Eisenthal, Kenneth B.

2018-06-01

Second harmonic generation (SHG) spectroscopy has been applied to probe the fused silica/water interface at pH 7 and the uncharged 11 ¯ 02 sapphire/water interface at pH 5.2 in contact with aqueous solutions of NaCl, NaBr, NaI, KCl, RbCl, and CsCl as low as several 10 μM. For ionic strengths up to about 0.1 mM, the SHG responses were observed to increase, reversibly for all salts surveyed, when compared to the condition of zero salt added. Further increases in the salt concentration led to monotonic decreases in the SHG response. The SHG increases followed by decreases are found to be consistent with recent reports of phase interference and phase matching in nonlinear optics. By varying the relative permittivity employed in common mean field theories used to describe electrical double layers and by comparing our results to available literature data, we find that models recapitulating the experimental observations are the ones in which (1) the relative permittivity of the diffuse layer is that of bulk water, with other possible values as low as 30, (2) the surface charge density varies with salt concentration, and (3) the charge in the Stern layer or its thickness varies with salt concentration. We also note that the experimental data exhibit sensitivity depending on whether the salt concentration is increased from low to high values or decreased from high to low values, which, however, is not borne out in the fits, at least within the current uncertainties associated with the model point estimates.

Virulence, pathology, and pathogenesis of Pteropine orthoreovirus (PRV) in BALB/c mice: Development of an animal infection model for PRV.

PubMed

Egawa, Kazutaka; Shimojima, Masayuki; Taniguchi, Satoshi; Nagata, Noriyo; Tani, Hideki; Yoshikawa, Tomoki; Kurosu, Takeshi; Watanabe, Shumpei; Fukushi, Shuetsu; Saijo, Masayuki

2017-12-01

Cases of acute respiratory tract infection caused by Pteropine orthoreovirus (PRV) of the genus Orthoreovirus (family: Reoviridae) have been reported in Southeast Asia, where it was isolated from humans and bats. It is possible that PRV-associated respiratory infections might be prevalent in Southeast Asia. The clinical course of PRV is not fully elucidated. The virulence, pathology, and pathogenesis of two PRV strains, a human-borne PRV strain (isolated from a patient, who returned to Japan from Bali, Indonesia in 2007) and a bat-borne PRV (isolated from a bat [Eonycteris spelaea] in the Philippines in 2013) were investigated in BALB/c mice using virological, pathological, and immunological study methods. The intranasal inoculation of BALB/c mice with human-borne PRV caused respiratory infection. In addition, all mice with immunity induced by pre-inoculation with a non-lethal dose of PRV were completely protected against lethal PRV infection. Mice treated with antiserum with neutralizing antibody activity after inoculation with a lethal dose of PRV showed a reduced fatality rate. In this mouse model, bat-borne PRV caused respiratory infection similar to human-borne PRV. PRV caused lethal respiratory disease in an animal model of PRV infection, in which BALB/c mice were used. The BALB/c mouse model might help to accelerate research on the virulence of PRV and be useful for evaluating the efficacy of therapeutic agents and vaccines for the treatment and prevention of PRV infection. PRV was shown for the first time to be a causative virus of respiratory disease on the basis of Koch's postulations by the additional demonstration that PRV caused respiratory disease in mice through their intranasal inoculation with PRV.

Understanding trends in Australian alcohol consumption-an age-period-cohort model.

PubMed

Livingston, Michael; Raninen, Jonas; Slade, Tim; Swift, Wendy; Lloyd, Belinda; Dietze, Paul

2016-09-01

To decompose Australian trends in alcohol consumption into their age, period (survey year) and cohort (birth year/generation) components. In particular, we aimed to test whether recent declines in overall consumption have been influenced by reductions in drinking among recently born cohorts. Seven cross-sectional waves of the Australian National Drug Strategy Household Survey (1995-2013). Age, period and cohort effects were estimated using a linear and logistic cross-classified random-effects models (CCREMs). Australia A total of 124 440 Australians (69 193 females and 55 257 males), aged 14-79 years. Whether or not respondents consumed alcohol in the 12 months prior to the survey and, for those who did, the estimated volume of pure alcohol consumed, derived using standard quantity-frequency survey questions. Controlling for age and period effects, there was significant variation in drinking participation and drinking volume by birth cohort. In particular, male cohorts born between the 1965 and 1974 and female cohorts born between 1955 and 1974 reported higher rates of drinking participation (P < 0.05), while the most recent cohorts (born in the 1990s) had lower rates of participation (P < 0.01). Among drinkers, the most recently born cohort also had sharply lower average consumption volumes than older cohorts for both men and women (P < 0.01). Recent birth cohorts (born between 1995 and 1999) in Australia report significantly lower rates of both drinking participation and drinking volume than previous cohorts, controlling for their age distribution and overall changes in population drinking. These findings suggest that the recent decline in alcohol consumption in Australia has been driven by declines in drinking among these recently born cohorts. These trends are consistent with international shifts in youth drinking. © 2016 Society for the Study of Addiction.

Urbanization factors associated with childhood asthma and prematurity: a population-based analysis aged from 0 to 5 years in Taiwan by using Cox regression within a hospital cluster model.

PubMed

Lin, Sheng-Chieh; Lin, Hui-Wen

2015-04-01

Childhood asthma and premature birth are both common; however, no studies have reported urbanization association between asthma and prematurity and the duration of prematurity affect asthma development. We use Taiwan Longitudinal Health Insurance Database (LHID) to explore association between asthma and prematurity among children by using a population-based analysis. This is a retrospective cohort study with registration data derived from Taiwan LHID. We evaluated prematurely born infants and children aged <5 years (n = 532) and age-matched control patients (n = 60505) using Cox proportional hazard regression analysis within a hospital cluster model. Of the 61 037 examinees, 14 012 experienced asthma during the 5-year follow-up, including 161 (72.26 per 1000 person-years) infants and children born prematurely and 13 851 (40.27 per 1000 person-years) controls. The hazard ratio for asthma during 5-year follow-up period was 1.95 (95% confidence interval = 1.67-2.28) among children born prematurely. Boys born prematurely aged 0-2 years were associated with higher asthma rates compared with girls in non-premature and premature groups. Living in urban areas, those born prematurely were associated with higher rates of asthma compared with non-prematurity. Those born prematurely lived in northern region had higher asthma hazard ratio than other regions. Our analyses indicated that sex, age, urbanization level, and geographic region are significantly associated with prematurity and asthma. Based on cumulative asthma-free survival curve generated using the Kaplan-Meier method, infants born prematurely should be closely monitored to see if they would develop asthma until the age of 6 years.

[Socioeconomic costs of food-borne disease using the cost-of-illness model: applying the QALY method].

PubMed

Shin, Hosung; Lee, Suehyung; Kim, Jong Soo; Kim, Jinsuk; Han, Kyu Hong

2010-07-01

This study estimated the annual socioeconomic costs of food-borne disease in 2008 from a societal perspective and using a cost-of-illness method. Our model employed a comprehensive set of diagnostic disease codes to define food-borne diseases with using the Korea National Health Insurance (KNHI) reimbursement data. This study classified the food borne illness as three types of symptoms according to the severity of the illness: mild, moderate, severe. In addition to the traditional method of assessing the cost-of-illness, the study included measures to account for the lost quality of life. We estimated the cost of the lost quality of life using quality-adjusted life years and a visual analog scale. The direct cost included medical and medication costs, and the non-medical costs included transportation costs, caregiver's cost and administration costs. The lost productivity costs included lost workdays due to illness and lost earnings due to premature death. The study found the estimated annual socioeconomic costs of food-borne disease in 2008 were 954.9 billion won (735.3 billion won-996.9 billion won). The medical cost was 73.4 - 76.8% of the cost, the lost productivity cost was 22.6% and the cost of the lost quality of life was 26.0%. Most of the cost-of-illness studies are known to have underestimated the actual socioeconomic costs of the subjects, and these studies excluded many important social costs, such as the value of pain, suffering and functional disability. The study addressed the uncertainty related to estimating the socioeconomic costs of food-borne disease as well as the updated cost estimates. Our estimates could contribute to develop and evaluate policies for food-borne disease.

Validity of the Born approximation for beyond Gaussian weak lensing observables

DOE PAGES

Petri, Andrea; Haiman, Zoltan; May, Morgan

2017-06-06

Accurate forward modeling of weak lensing (WL) observables from cosmological parameters is necessary for upcoming galaxy surveys. Because WL probes structures in the nonlinear regime, analytical forward modeling is very challenging, if not impossible. Numerical simulations of WL features rely on ray tracing through the outputs of N-body simulations, which requires knowledge of the gravitational potential and accurate solvers for light ray trajectories. A less accurate procedure, based on the Born approximation, only requires knowledge of the density field, and can be implemented more efficiently and at a lower computational cost. In this work, we use simulations to show thatmore » deviations of the Born-approximated convergence power spectrum, skewness and kurtosis from their fully ray-traced counterparts are consistent with the smallest nontrivial O(Φ 3) post-Born corrections (so-called geodesic and lens-lens terms). Our results imply a cancellation among the larger O(Φ 4) (and higher order) terms, consistent with previous analytic work. We also find that cosmological parameter bias induced by the Born-approximated power spectrum is negligible even for a LSST-like survey, once galaxy shape noise is considered. When considering higher order statistics such as the κ skewness and kurtosis, however, we find significant bias of up to 2.5σ. Using the LensTools software suite, we show that the Born approximation saves a factor of 4 in computing time with respect to the full ray tracing in reconstructing the convergence.« less

Validity of the Born approximation for beyond Gaussian weak lensing observables

NASA Astrophysics Data System (ADS)

Petri, Andrea; Haiman, Zoltán; May, Morgan

2017-06-01

Accurate forward modeling of weak lensing (WL) observables from cosmological parameters is necessary for upcoming galaxy surveys. Because WL probes structures in the nonlinear regime, analytical forward modeling is very challenging, if not impossible. Numerical simulations of WL features rely on ray tracing through the outputs of N -body simulations, which requires knowledge of the gravitational potential and accurate solvers for light ray trajectories. A less accurate procedure, based on the Born approximation, only requires knowledge of the density field, and can be implemented more efficiently and at a lower computational cost. In this work, we use simulations to show that deviations of the Born-approximated convergence power spectrum, skewness and kurtosis from their fully ray-traced counterparts are consistent with the smallest nontrivial O (Φ3) post-Born corrections (so-called geodesic and lens-lens terms). Our results imply a cancellation among the larger O (Φ4) (and higher order) terms, consistent with previous analytic work. We also find that cosmological parameter bias induced by the Born-approximated power spectrum is negligible even for a LSST-like survey, once galaxy shape noise is considered. When considering higher order statistics such as the κ skewness and kurtosis, however, we find significant bias of up to 2.5 σ . Using the LensTools software suite, we show that the Born approximation saves a factor of 4 in computing time with respect to the full ray tracing in reconstructing the convergence.

Feasibility of observer system for determining orientation of balloon borne observational platforms

NASA Technical Reports Server (NTRS)

Nigro, N. J.; Gagliardi, J. C.

1982-01-01

The instantaneous orientation (i.e., the attitude) of the LACATE instrumentation platform with respect to a local vertical is discussed. An observer model for predicting the orientation of balloon-borne research platforms is described. Determination of the platform orientation as a function of time is addressed.

The Latino Paradox in Neighborhood Context: The Case of Asthma and Other Respiratory Conditions

PubMed Central

Cagney, Kathleen A.; Browning, Christopher R.; Wallace, Danielle M.

2007-01-01

Objectives. Evidence indicates that foreign-born Latinos have a health advantage compared with US-born persons of the same socioeconomic status. An explanation for this paradox has remained elusive. We examined the extent to which this paradox exists for the prevalence of asthma and other respiratory conditions. We then explored the role of neighborhood social context in understanding any observed advantage. We invoked theories of social organization, collective efficacy, and the urban ethnic enclave. Methods. We combined data from the Project on Human Development in Chicago Neighborhoods Community Survey with 2 other data sources and used hierarchical generalized linear modeling techniques. Results. We found a distinctly graded effect for asthma and other breathing problems among foreign-born Latinos, depending on community composition. Foreign-born Latinos embedded in a neighborhood that had a high percentage of foreign-born residents experienced a significantly lower prevalence of asthma and other breathing problems; those in communities that had a low percentage of foreign-born residents had the highest prevalence overall (even when compared with African Americans). Conclusions. Foreign-born Latinos have a respiratory health advantage only in enclave-like settings. Contexts such as these may provide the cohesiveness critical for effective prevention. PMID:17395846

Health Insurance Coverage and Access to Care Among US-Born and Foreign-Born Sexual Minorities.

PubMed

Gonzales, Gilbert; Dedania, Reema; Driscoll, Ryan

2018-06-26

Sexual minorities and immigrants face unique challenges to accessing health care in the United States. This study used data on nonelderly adults (n = 100,667) from the 2013-2016 National Health Interview Survey. Unadjusted prevalence estimates and multivariable logistic regression models (with and without interactions between immigration and sexual minority status) were used to compare health insurance coverage and access to care by immigration and sexual minority status. We did not find any differences in uninsurance, having a usual source of care, and a recent office visit by sexual orientation for US-born and foreign-born adults. However, compared to their heterosexual counterparts, US-born and foreign-born sexual minorities were more likely to have an emergency room visit in the prior year and report financial-related barriers to medical care, dental care, prescription medications, and mental health care. Foreign-born sexual minorities were more likely to have an emergency room visit and unmet mental health care needs due to cost compared to other subpopulations after controlling for sociodemographic characteristics. Broadening the knowledge and scope of research on sexual minority immigrants can inform targeted health policy approaches with the goal of achieving health equity for sexual minority immigrants.

Beyond-Born-Oppenheimer effects in sub-kHz-precision photoassociation spectroscopy of ytterbium atoms

NASA Astrophysics Data System (ADS)

Borkowski, Mateusz; Buchachenko, Alexei A.; Ciuryło, Roman; Julienne, Paul S.; Yamada, Hirotaka; Kikuchi, Yuu; Takahashi, Kakeru; Takasu, Yosuke; Takahashi, Yoshiro

2017-12-01

We present high-resolution two-color photoassociation spectroscopy of Bose-Einstein condensates of ytterbium atoms. The use of narrow Raman resonances and careful examination of systematic shifts enabled us to measure 13 bound-state energies for three isotopologues of the ground-state ytterbium molecule with standard uncertainties of the order of 500 Hz. The atomic interactions are modeled using an ab initio based mass-scaled Born-Oppenheimer potential whose long-range van der Waals parameters and total WKB phase are fitted to experimental data. We find that the quality of the fit of this model, of about 112.9 kHz (rms) can be significantly improved by adding the recently calculated beyond-Born-Oppenheimer (BBO) adiabatic corrections [J. J. Lutz and J. M. Hutson, J. Mol. Spectrosc. 330, 43 (2016), 10.1016/j.jms.2016.08.007] and by partially treating the nonadiabatic effects using distance-dependent reduced masses. Our BBO interaction model represents the experimental data to within about 30.2 kHz on average, which is 3.7 times better than the "reference" Born-Oppenheimer model. We calculate the s -wave scattering lengths for bosonic isotopic pairs of ytterbium atoms with error bars over two orders of magnitude smaller than previous determinations. For example, the s -wave scattering length for 174Yb is +5.55812 (50 ) nm.

Leading indicators of mosquito-borne disease elimination.

PubMed

O'Regan, Suzanne M; Lillie, Jonathan W; Drake, John M

Mosquito-borne diseases contribute significantly to the global disease burden. High-profile elimination campaigns are currently underway for many parasites, e.g., Plasmodium spp., the causal agent of malaria. Sustaining momentum near the end of elimination programs is often difficult to achieve and consequently quantitative tools that enable monitoring the effectiveness of elimination activities after the initial reduction of cases has occurred are needed. Documenting progress in vector-borne disease elimination is a potentially important application for the theory of critical transitions. Non-parametric approaches that are independent of model-fitting would advance infectious disease forecasting significantly. In this paper, we consider compartmental Ross-McDonald models that are slowly forced through a critical transition through gradually deployed control measures. We derive expressions for the behavior of candidate indicators, including the autocorrelation coefficient, variance, and coefficient of variation in the number of human cases during the approach to elimination. We conducted a simulation study to test the performance of each summary statistic as an early warning system of mosquito-borne disease elimination. Variance and coefficient of variation were highly predictive of elimination but autocorrelation performed poorly as an indicator in some control contexts. Our results suggest that tipping points (bifurcations) in mosquito-borne infectious disease systems may be foreshadowed by characteristic temporal patterns of disease prevalence.

Country-of-birth differences in adverse health behaviours among people with type 2 diabetes.

PubMed

Shamshirgaran, Seyed Morteza; Jorm, Louisa; Bambrick, Hilary; Hennessy, Annemarie

2015-06-01

To identify differences in patterns of adverse health behaviours among people with type 2 diabetes according to country or region of birth. Population-based study of 23,112 individuals with type 2 diabetes aged 45 years and older, from New South Wales, Australia. Self-reported questionnaire data and logistic regression models were used to estimate odds ratios for adverse health behaviours according to country or region of birth, adjusted for confounding factors. People with diabetes born in the Middle East and in the United Kingdom (UK) were more likely to be current smokers than those born in Australian, while those from Asia were less likely to be smokers. Relative to Australian-born people with diabetes, those born in the Middle East were more likely to have insufficient physical activity, while those born in Oceania, North West Europe and the UK were less likely. People with diabetes from Asia, North Africa, the Middle East and Sub-Saharan Africa were less likely to consume alcohol than those born in Australia, but people born in the UK were slightly more likely to consume alcohol. People with diabetes born in the UK, Asia, and North Africa were more likely than those born in Australia to have an inadequate intake of fruit and vegetables. Adverse health behaviours among people with type 2 diabetes varied markedly according to country or region of birth. Promoting smoking cessation and increasing physical activity levels among people with diabetes who were born in Middle Eastern countries are clear priorities. © 2014 Public Health Association of Australia.

Rabies Tracing of Birthdated Dentate Granule Cells in Rat Temporal Lobe Epilepsy

PubMed Central

Du, Xi; Zhang, Helen; Parent, Jack M.

2017-01-01

Objective To understand how monosynaptic inputs onto adult-born dentate granule cells (DGCs) are altered in experimental mesial temporal lobe epilepsy (mTLE) and whether their integration differs from early-born DGCs that are mature at the time of epileptogenesis. Methods A dual-virus tracing strategy combining retroviral birthdating with rabies virus-mediated putative retrograde trans-synaptic tracing was used to identify and compare presynaptic inputs onto adult- and early-born DGCs in the rat pilocarpine model of mTLE. Results Our results demonstrate that hilar ectopic DGCs preferentially synapse onto adult-born DGCs after pilocarpine-induced status epilepticus (SE) while normotopic DGCs synapse onto both adult- and early-born DGCs. We also find that parvalbumin+ and somatostatin+ interneuron inputs are greatly diminished onto early-born DGCs after SE. However, somatostatin+ interneuron inputs onto adult-born DGCs are maintained, likely due to preferential sprouting. Intriguingly, CA3 pyramidal cell backprojections that specifically target adult-born DGCs arise in the epileptic brain, while axons of interneurons and pyramidal cells in CA1 appear to sprout across the hippocampal fissure to preferentially synapse onto early-born DGCs. Interpretation These data support the presence of substantial hippocampal circuit remodeling after an epileptogenic insult that generates prominent excitatory monosynaptic inputs, both local recurrent and widespread feedback loops, involving DGCs. Both adult- and early-born DGCs are targets of new inputs from other DGCs as well as from CA3 and CA1 pyramidal cells after pilocarpine-treatment, changes that likely contribute to epileptogenesis in experimental mTLE. PMID:28470680

Psychosocial stress factors and intention to leave job: differences between foreign-born and Finnish-born general practitioners.

PubMed

Kuusio, Hannamaria; Heponiemi, Tarja; Vänskä, Jukka; Aalto, Anna-Mari; Ruskoaho, Juho; Elovainio, Marko

2013-06-01

Physicians' high dropout rate is a significant problem in primary care in many countries. One solution to this issue is to recruit internationally mobile physicians. This study explores the role of psychosocial factors in explaining intention to leave among GPs including potential differences between foreign-born and Finnish GPs. A cross-sectional questionnaire was sent to randomly-selected Finnish physicians (n = 7000) and all foreign-born physicians (n = 1297) living in Finland in the year 2010. The questionnaire was returned by 4333 physicians, of whom 832 were GPs. Of those 176 were foreign-born GPs. Intention to leave was more common among foreign-born GPs (59%) than among Finnish GPs (52%). High job demands were associated with higher intention to leave from primary care both in foreign-born (OR 1.90) and Finnish GPs (OR 2.20). This association remained among foreign-born GPs after adjusted the model for the country of origin or the reason for migration (OR 1.80, 1.82). Lack of job control, patient-related stress, and stresses related to teamwork were associated with higher intention to leave only among Finnish GPs (ORs 0.45, 1.75 and 1.99). There may be cultural differences in the psychosocial factors that enhance or prevent job involvement among physicians. Thus, novel thinking is needed in organizational development of GP work in order to better understand foreign-born physicians' specific needs in a target country. This study also suggests that lightening workload could help to attract more GPs, both foreign-born and Finnish, to primary care.

Strategic parenting, birth order, and school performance.

PubMed

Hotz, V Joseph; Pantano, Juan

2015-10-01

Fueled by new evidence, there has been renewed interest about the effects of birth order on human capital accumulation. The underlying causal mechanisms for such effects remain unsettled. We consider a model in which parents impose more stringent disciplinary environments in response to their earlier-born children's poor performance in school in order to deter such outcomes for their later-born offspring. We provide robust empirical evidence that school performance of children in the National Longitudinal Study Children (NLSY-C) declines with birth order as does the stringency of their parents' disciplinary restrictions. When asked how they will respond if a child brought home bad grades, parents state that they would be less likely to punish their later-born children. Taken together, these patterns are consistent with a reputation model of strategic parenting.

Strategic parenting, birth order, and school performance

PubMed Central

Pantano, Juan

2015-01-01

Fueled by new evidence, there has been renewed interest about the effects of birth order on human capital accumulation. The underlying causal mechanisms for such effects remain unsettled. We consider a model in which parents impose more stringent disciplinary environments in response to their earlier-born children’s poor performance in school in order to deter such outcomes for their later-born offspring. We provide robust empirical evidence that school performance of children in the National Longitudinal Study Children (NLSY-C) declines with birth order as does the stringency of their parents’ disciplinary restrictions. When asked how they will respond if a child brought home bad grades, parents state that they would be less likely to punish their later-born children. Taken together, these patterns are consistent with a reputation model of strategic parenting. PMID:26366045

Light-by-Light Scattering Constraint on Born-Infeld Theory

NASA Astrophysics Data System (ADS)

Ellis, John; Mavromatos, Nick E.; You, Tevong

2017-06-01

The recent measurement by ATLAS of light-by-light scattering in LHC Pb-Pb collisions is the first direct evidence for this basic process. We find that it excludes a range of the mass scale of a nonlinear Born-Infeld extension of QED that is ≲100 GeV , a much stronger constraint than those derived previously. In the case of a Born-Infeld extension of the standard model in which the U(1 ) Y hypercharge gauge symmetry is realized nonlinearly, the limit on the corresponding mass reach is ˜90 GeV , which, in turn, imposes a lower limit of ≳11 TeV on the magnetic monopole mass in such a U(1 ) Y Born-Infeld theory.

Using two detectors concurrently to monitor ambient dose equivalent rates in vehicle surveys of radiocesium contaminated land.

PubMed

Takeishi, Minoru; Shibamichi, Masaru; Malins, Alex; Kurikami, Hiroshi; Murakami, Mitsuhiro; Saegusa, Jun; Yoneya, Masayuki

2017-10-01

In response to the accident at Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP), vehicle-borne monitoring was used to map radiation levels for radiological protection of the public. By convention measurements from vehicle-borne surveys are converted to the ambient dose equivalent rate at 1 m height in the absence of the vehicle. This allows for comparison with results from other types of survey, including surveys with hand-held or airborne instruments. To improve the accuracy of the converted results from vehicle-borne surveys, we investigated combining measurements from two detectors mounted on the vehicle at different heights above the ground. A dual-detector setup was added to a JAEA monitoring car and compared against hand-held survey meter measurements in Fukushima Prefecture. The results obtained by combining measurements from two detectors were within ±20% of the hand-held reference measurements. The mean absolute percentage deviation from the reference measurements was 7.2%. The combined results from the two detectors were more accurate than those from either the roof-mounted detector, or the detector inside the vehicle, taken alone. One issue with vehicle-borne surveys is that ambient dose equivalent rates above roads are not necessarily representative of adjacent areas. This is because radiocesium is often deficient on asphalt surfaces, as it is easily scrubbed off by rain, wind and vehicle tires. To tackle this issue, we investigated mounting heights for vehicle-borne detectors using Monte Carlo gamma-ray simulations. When radiocesium is deficient on a road compared to the adjacent land, mounting detectors high on vehicles yields results closer to the values adjacent to the road. The ratio of ambient dose equivalent rates reported by detectors mounted at different heights in a dual-detector setup indicates whether radiocesium is deficient on the road compared to the adjacent land. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multi-agent systems in epidemiology: a first step for computational biology in the study of vector-borne disease transmission.

PubMed

Roche, Benjamin; Guégan, Jean-François; Bousquet, François

2008-10-15

Computational biology is often associated with genetic or genomic studies only. However, thanks to the increase of computational resources, computational models are appreciated as useful tools in many other scientific fields. Such modeling systems are particularly relevant for the study of complex systems, like the epidemiology of emerging infectious diseases. So far, mathematical models remain the main tool for the epidemiological and ecological analysis of infectious diseases, with SIR models could be seen as an implicit standard in epidemiology. Unfortunately, these models are based on differential equations and, therefore, can become very rapidly unmanageable due to the too many parameters which need to be taken into consideration. For instance, in the case of zoonotic and vector-borne diseases in wildlife many different potential host species could be involved in the life-cycle of disease transmission, and SIR models might not be the most suitable tool to truly capture the overall disease circulation within that environment. This limitation underlines the necessity to develop a standard spatial model that can cope with the transmission of disease in realistic ecosystems. Computational biology may prove to be flexible enough to take into account the natural complexity observed in both natural and man-made ecosystems. In this paper, we propose a new computational model to study the transmission of infectious diseases in a spatially explicit context. We developed a multi-agent system model for vector-borne disease transmission in a realistic spatial environment. Here we describe in detail the general behavior of this model that we hope will become a standard reference for the study of vector-borne disease transmission in wildlife. To conclude, we show how this simple model could be easily adapted and modified to be used as a common framework for further research developments in this field.

Phonon assisted carrier motion on the Wannier-Stark ladder

NASA Astrophysics Data System (ADS)

Cheung, Alfred; Berciu, Mona

2014-03-01

It is well known that at zero temperature and in the absence of electron-phonon coupling, the presence of an electric field leads to localization of carriers residing in a single band of finite bandwidth. In this talk, we will present an implementation of the self-consistent Born approximation (SCBA) to study the effect of weak electron-phonon coupling on the motion of a carrier in a biased system. At moderate and strong electron-phonon coupling, we supplement the SCBA, describing the string of phonons left behind by the carrier, with the momentum average approximation to describe the phonon cloud that accompanies the resulting polaron. We find that coupling to the lattice delocalizes the carrier, as expected, although long-lived resonances resulting from the Wannier-Stark states of the polaron may appear in certain regions of the parameter space. We end with a discussion of how our method can be improved to model disorder, other types of electron-phonon coupling, and electron-hole pair dissociation in a biased system.

Clinical utility of T-wave alternans

NASA Technical Reports Server (NTRS)

Armoundas, A. A.; Cohen, R. J.

1997-01-01

Electrical alternans represents a variation in the morphology of electrocardiographic complexes on an every-other-beat basis in an ABABAB... pattern. Apparent electrical alternans associated with pericardial effusion results from rotation of the heart in the pericardial sac, and not true alternation in electrical conduction patterns. In contrast, true electrical alternans results from an alternation in electrical conduction patterns in the heart itself. Repolarization alternans is true electrical alternans associated with the ST segment and T wave of the electrocardiogram (ECG). Here we will focus on T-wave alternans (TWA) and its association with susceptibility to ventricular tachyarrhythmias. Electrical alternans was reported in the literature as early as 1909. Historically, electrical alternans has been regarded as a fairly rare electrocardiographic abnormality. Case reports of electrical alternans have been associated with a variety of disease states, including acute ischemia, Prinzmetal's angina, a variety of electrolyte abnormalities, and the long QT syndrome. Interestingly, patients born with the prolonged QT syndrome have a very high incidence of sudden cardiac death at an early age. Schwartz and Malliani showed that patients with the prolonged QT syndrome who do not demonstrate alternans at rest, may evidence alternans during stress such as emotional excitement. Thus, over the years electrical alternans has been associated anecdotally with conditions associated with an increased risk of ventricular arrhythmias. In 1948, Kalter reviewed the world literature on electrical alternans and found a total of 41 reported cases. In addition, he reviewed clinical ectrocardiograms from 6059 patients and found five new cases (incidence of less than 1 in 1000 patients). Interestingly, he found a very high mortality, 62%, associated with this condition. Despite the clinical associations reported in the literature, the consensus view of electrical alternans until recent years has been that alternans is an electrocardiographic curiosity rarely encountered in clinical practice which, when identified, does not have specific clinical significance.

Age at migration and self-rated health trajectories after age 50: understanding the older immigrant health paradox.

PubMed

Gubernskaya, Zoya

2015-03-01

This research contributes to the "immigrant health paradox" debate by testing the hypothesis that older age at migration is associated with the increased risk of poor health in later life. Using the 1992-2008 Health and Retirement Study, I construct linear random-intercept models to estimate self-rated health (SRH) trajectories after age 50 for the native and foreign born by age at migration. At age 50, both Hispanic and non-Hispanic foreign born report better SRH compared with their native-born counterparts, net of race, gender, and education. Non-Hispanic foreign born who migrated after age 35 and Hispanic foreign born who migrated after age 18, however, experience steeper decline in SRH after age 50, which results in a health disadvantage vis-à-vis the native born in old age. Education has a smaller protective effect on SRH for the foreign born, especially those who migrated as adults. Age at migration is an important factor for understanding health status of older immigrants. Steeper health decline in later life of the foreign born who migrated in advanced ages may be related to longer exposure to unfavorable conditions in home countries and limited opportunities for incorporation in the United States. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Influence of vectors' risk-spreading strategies and environmental stochasticity on the epidemiology and evolution of vector-borne diseases: the example of Chagas' disease.

PubMed

Pelosse, Perrine; Kribs-Zaleta, Christopher M; Ginoux, Marine; Rabinovich, Jorge E; Gourbière, Sébastien; Menu, Frédéric

2013-01-01

Insects are known to display strategies that spread the risk of encountering unfavorable conditions, thereby decreasing the extinction probability of genetic lineages in unpredictable environments. To what extent these strategies influence the epidemiology and evolution of vector-borne diseases in stochastic environments is largely unknown. In triatomines, the vectors of the parasite Trypanosoma cruzi, the etiological agent of Chagas' disease, juvenile development time varies between individuals and such variation most likely decreases the extinction risk of vector populations in stochastic environments. We developed a simplified multi-stage vector-borne SI epidemiological model to investigate how vector risk-spreading strategies and environmental stochasticity influence the prevalence and evolution of a parasite. This model is based on available knowledge on triatomine biodemography, but its conceptual outcomes apply, to a certain extent, to other vector-borne diseases. Model comparisons between deterministic and stochastic settings led to the conclusion that environmental stochasticity, vector risk-spreading strategies (in particular an increase in the length and variability of development time) and their interaction have drastic consequences on vector population dynamics, disease prevalence, and the relative short-term evolution of parasite virulence. Our work shows that stochastic environments and associated risk-spreading strategies can increase the prevalence of vector-borne diseases and favor the invasion of more virulent parasite strains on relatively short evolutionary timescales. This study raises new questions and challenges in a context of increasingly unpredictable environmental variations as a result of global climate change and human interventions such as habitat destruction or vector control.

Influence of Vectors’ Risk-Spreading Strategies and Environmental Stochasticity on the Epidemiology and Evolution of Vector-Borne Diseases: The Example of Chagas’ Disease

PubMed Central

Pelosse, Perrine; Kribs-Zaleta, Christopher M.; Ginoux, Marine; Rabinovich, Jorge E.; Gourbière, Sébastien; Menu, Frédéric

2013-01-01

Insects are known to display strategies that spread the risk of encountering unfavorable conditions, thereby decreasing the extinction probability of genetic lineages in unpredictable environments. To what extent these strategies influence the epidemiology and evolution of vector-borne diseases in stochastic environments is largely unknown. In triatomines, the vectors of the parasite Trypanosoma cruzi, the etiological agent of Chagas’ disease, juvenile development time varies between individuals and such variation most likely decreases the extinction risk of vector populations in stochastic environments. We developed a simplified multi-stage vector-borne SI epidemiological model to investigate how vector risk-spreading strategies and environmental stochasticity influence the prevalence and evolution of a parasite. This model is based on available knowledge on triatomine biodemography, but its conceptual outcomes apply, to a certain extent, to other vector-borne diseases. Model comparisons between deterministic and stochastic settings led to the conclusion that environmental stochasticity, vector risk-spreading strategies (in particular an increase in the length and variability of development time) and their interaction have drastic consequences on vector population dynamics, disease prevalence, and the relative short-term evolution of parasite virulence. Our work shows that stochastic environments and associated risk-spreading strategies can increase the prevalence of vector-borne diseases and favor the invasion of more virulent parasite strains on relatively short evolutionary timescales. This study raises new questions and challenges in a context of increasingly unpredictable environmental variations as a result of global climate change and human interventions such as habitat destruction or vector control. PMID:23951018

Runoff delay exerts a strong control on the field-scale removal of manure-borne fecal bacteria with runoff

USDA-ARS?s Scientific Manuscript database

The microbial safety of surface waters is an ongoing issue which is threatened by the transport of manure-borne bacteria to water sources used for irrigation or recreation. Predictive modeling has become an effective tool to forecast the microbial quality of water duringprecipitation events, however...

General framework for comparative quantitative studies on transmission of tick-borne diseases using Lyme borreliosis in Europe as an example.

PubMed

Randolph, S E; Craine, N G

1995-11-01

Models of tick-borne diseases must take account of the particular biological features of ticks that contrast with those of insect vectors. A general framework is proposed that identifies the parameters of the transmission dynamics of tick-borne diseases to allow a quantitative assessment of the relative contributions of different host species and alternative transmission routes to the basic reproductive number, Ro, of such diseases. Taking the particular case of the transmission of the Lyme borreliosis spirochaete, Borrelia burgdorferi, by Ixodes ticks in Europe, and using the best, albeit still inadequate, estimates of the parameter values and a set of empirical data from Thetford Forest, England, we show that squirrels and the transovarial transmission route make quantitatively very significant contributions to Ro. This approach highlights the urgent need for more robust estimates of certain crucial parameter values, particularly the coefficients of transmission between ticks and vertebrates, before we can progress to full models that incorporate seasonality and heterogeneity among host populations for the natural dynamics of transmission of borreliosis and other tick-borne diseases.

Detection of lower tropospheric responses to solar energetic particles at midlatitudes.

PubMed

Nicoll, K A; Harrison, R G

2014-06-06

Solar energetic particles (SEPs) occasionally contribute additional atmospheric ionization beyond that arising from the usual galactic cosmic ray background. During an SEP event associated with a solar flare on April 11, 2013, the vertical ionization rate profile obtained using a balloon-borne detector showed enhanced ionization with a 26% increase at 20 km, over Reading, United Kingdom. Fluctuations in atmospheric electrical parameters were also detected at the surface, beneath the balloon's trajectory. As no coincident changes in geomagnetism occurred, the electrical fluctuations are very likely to be associated with increased ionization, as observed by the balloon measurements. The lack of response of surface neutron monitors during this event indicates that energetic particles that are not detected at the surface by neutron monitors can nevertheless enter and influence the atmosphere's weather-generating regions.

Free-Space Optical Interconnect Employing VCSEL Diodes

NASA Technical Reports Server (NTRS)

Simons, Rainee N.; Savich, Gregory R.; Torres, Heidi

2009-01-01

Sensor signal processing is widely used on aircraft and spacecraft. The scheme employs multiple input/output nodes for data acquisition and CPU (central processing unit) nodes for data processing. To connect 110 nodes and CPU nodes, scalable interconnections such as backplanes are desired because the number of nodes depends on requirements of each mission. An optical backplane consisting of vertical-cavity surface-emitting lasers (VCSELs), VCSEL drivers, photodetectors, and transimpedance amplifiers is the preferred approach since it can handle several hundred megabits per second data throughput.The next generation of satellite-borne systems will require transceivers and processors that can handle several Gb/s of data. Optical interconnects have been praised for both their speed and functionality with hopes that light can relieve the electrical bottleneck predicted for the near future. Optoelectronic interconnects provide a factor of ten improvement over electrical interconnects.

Ethnic differences in self reported health in Malmö in southern Sweden

PubMed Central

Lindstrom, M; Sundquist, J; Ostergren, P

2001-01-01

STUDY OBJECTIVE—The aim of this study was to investigate ethnic differences in self reported health in the city of Malmö, Sweden, and whether these differences could be explained by psychosocial and economic conditions.
DESIGN/SETTING/PARTICIPANTS—The public health survey in Malmö 1994 was a cross sectional study. A total of 5600 people aged 20-80 years completed a postal questionnaire. The participation rate was 71%. The population was categorised according to country of origin: born in Sweden, other Western countries, Yugoslavia, Poland, Arabic speaking countries and all other countries. The multivariate analysis was performed using a logistic regression model in order to investigate the importance of possible confounders on the differences by country of origin in self reported health. Finally, variables measuring psychosocial and economic conditions were introduced into the model.
MAIN RESULTS—The odds ratios of having poor self reported health were significantly higher among men born in other Western countries, Yugoslavia, Arabic speaking countries and in the category all other countries, as well as among women born in Yugoslavia, Poland and all other countries, compared with men and women born in Sweden. The multivariate analysis including age and education did not change these results. A huge reduction of the odds ratios was observed for men and women born in Yugoslavia, Arabic speaking countries and all other countries, and for women born in Poland after the introduction of the social network, social support and economic factors into the multivariate model.
CONCLUSIONS—There were significant ethnic group differences in self reported health. These differences were greatly reduced by psychosocial and economic factors, which suggest that these factors may be important determinants of self rated health in certain minority groups.


Keywords: self reported health; social network; social support PMID:11154248

Infants born preterm demonstrate impaired object exploration behaviors throughout infancy and toddlerhood.

PubMed

Lobo, Michele A; Kokkoni, Elena; Cunha, Andrea Baraldi; Galloway, James Cole

2015-01-01

Object exploration behaviors form the foundation for future global development, but little is known about how these behaviors are exhibited by infants born preterm. The study objective was to longitudinally compare a comprehensive set of object exploration behaviors in infants born preterm and infants born full-term from infancy into toddlerhood. Twenty-two infants born full-term and 28 infants born preterm were monitored as they interacted with objects throughout their first 2 years. Infants were provided up to 30 seconds to interact with each of 7 objects across 9 visits. Experimenters coded videos of infants' behaviors. Growth modeling and t tests were used to compare how much infants exhibited behaviors and how well they matched their behaviors to the properties of objects. Infants born preterm explored objects less in the first 6 months, exhibited less visual-haptic multimodal exploration, displayed reduced variability of exploratory behavior in a manner that reflected severity of risk, and were less able to match their behaviors to the properties of objects in a manner that reflected severity of risk. Infants born preterm with significant brain injury also had impaired bimanual abilities. There was a limited sample of infants born preterm with significant brain injury. Infants born preterm have impaired abilities to interact with objects even in the first months of life. This impairment likely limits the knowledge they acquire about objects and about how they can act on them; this limited knowledge may, in turn, impair their early learning abilities. These results highlight the need for assessment and intervention tools specific for object exploration in young infants. © 2015 American Physical Therapy Association.

Infants Born Preterm Demonstrate Impaired Object Exploration Behaviors Throughout Infancy and Toddlerhood

PubMed Central

Kokkoni, Elena; Cunha, Andrea Baraldi; Galloway, James Cole

2015-01-01

Background Object exploration behaviors form the foundation for future global development, but little is known about how these behaviors are exhibited by infants born preterm. Objective The study objective was to longitudinally compare a comprehensive set of object exploration behaviors in infants born preterm and infants born full-term from infancy into toddlerhood. Design Twenty-two infants born full-term and 28 infants born preterm were monitored as they interacted with objects throughout their first 2 years. Methods Infants were provided up to 30 seconds to interact with each of 7 objects across 9 visits. Experimenters coded videos of infants' behaviors. Growth modeling and t tests were used to compare how much infants exhibited behaviors and how well they matched their behaviors to the properties of objects. Results Infants born preterm explored objects less in the first 6 months, exhibited less visual-haptic multimodal exploration, displayed reduced variability of exploratory behavior in a manner that reflected severity of risk, and were less able to match their behaviors to the properties of objects in a manner that reflected severity of risk. Infants born preterm with significant brain injury also had impaired bimanual abilities. Limitations There was a limited sample of infants born preterm with significant brain injury. Conclusions Infants born preterm have impaired abilities to interact with objects even in the first months of life. This impairment likely limits the knowledge they acquire about objects and about how they can act on them; this limited knowledge may, in turn, impair their early learning abilities. These results highlight the need for assessment and intervention tools specific for object exploration in young infants. PMID:25169919

Effects of Nativity, Length of Residence, and County-Level Foreign-Born Density on Mental Health Among Older Adults in the U.S

PubMed Central

Choi, Sunha; Kim, Giyeon

2016-01-01

Using the 2004–2007 Medical Expenditure Panel Survey data that are linked to county-level data from the Area Health Resources Files, this study examined whether the healthy immigrant effect applies to mental health of foreign-born older adults. Additionally, testing a protective ethnic density effect on older foreign-born individuals’ mental health, this study examined how the percentage of foreign-born population in the county affected the relationship between older adults’ immigration status (U.S.-nativity and length of residence in the U.S.) and their mental health status. The sample included 29,011 individuals (level-1) from 920 counties (level-2) across 50 states and D.C. Using the Mental Component Summary of the Short-Form 12, the Kessler Index (K-6), and the Patient Health Questionnaire (PHQ-2), U.S.-born individuals (n = 24,225), earlier immigrants (≥15 years in the U.S.; n = 3866), and recent immigrants (<15 years in the U.S.; n = 920) were compared. The results indicate that recent immigrants showed worse mental health on all three measures compared with U.S.-born individuals and on the K-6 and PHQ-2 compared with earlier immigrants. Higher county-level foreign-born densities were associated with worse mental health status of individuals. However, the significant interactions found in the full conditional multilevel models indicated that the high foreign-born density functioned as a risk factor for worse mental health only among recent immigrants but not among the U.S.-born. In conclusion, the results revealed the vulnerability of older recent immigrants, especially those living in the counties with high foreign-born densities. PMID:26910461

Effects of Nativity, Length of Residence, and County-Level Foreign-Born Density on Mental Health Among Older Adults in the U.S.

PubMed

Choi, Sunha; Kim, Giyeon; Lee, Sungkyu

2016-12-01

Using the 2004-2007 Medical Expenditure Panel Survey data that are linked to county-level data from the Area Health Resources Files, this study examined whether the healthy immigrant effect applies to mental health of foreign-born older adults. Additionally, testing a protective ethnic density effect on older foreign-born individuals' mental health, this study examined how the percentage of foreign-born population in the county affected the relationship between older adults' immigration status (U.S.-nativity and length of residence in the U.S.) and their mental health status. The sample included 29,011 individuals (level-1) from 920 counties (level-2) across 50 states and D.C. Using the Mental Component Summary of the Short-Form 12, the Kessler Index (K-6), and the Patient Health Questionnaire (PHQ-2), U.S.-born individuals (n = 24,225), earlier immigrants (≥15 years in the U.S.; n = 3866), and recent immigrants (<15 years in the U.S.; n = 920) were compared. The results indicate that recent immigrants showed worse mental health on all three measures compared with U.S.-born individuals and on the K-6 and PHQ-2 compared with earlier immigrants. Higher county-level foreign-born densities were associated with worse mental health status of individuals. However, the significant interactions found in the full conditional multilevel models indicated that the high foreign-born density functioned as a risk factor for worse mental health only among recent immigrants but not among the U.S.-born. In conclusion, the results revealed the vulnerability of older recent immigrants, especially those living in the counties with high foreign-born densities.

Individual- and neighborhood-level contextual factors are associated with Mycobacterium tuberculosis transmission: genotypic clustering of cases in Michigan, 2004-2012.

PubMed

Noppert, Grace A; Yang, Zhenhua; Clarke, Philippa; Ye, Wen; Davidson, Peter; Wilson, Mark L

2017-06-01

Using genotyping data of Mycobacterium tuberculosis isolates from new cases reported to the tuberculosis (TB) surveillance program, we evaluated risk factors for recent TB transmission at both the individual- and neighborhood- levels among U.S.-born and foreign-born populations. TB cases (N = 1236) reported in Michigan during 2004 to 2012 were analyzed using multivariable Poisson regression models to examine risk factors for recent transmission cross-sectionally for U.S.-born and foreign-born populations separately. Recent transmission was defined based on spoligotype and 12-locus-mycobacterial interspersed repetitive unit-variable number tandem repeat typing matches of bacteria from cases that were diagnosed within 1 year of each other. Four classes of predictor variables were examined: demographic factors, known TB risk factors, clinical characteristics, and neighborhood-level factors. Overall, 22% of the foreign-born cases resulted from recent transmission. Among the foreign-born, race and being a contact of an infectious TB case were significant predictors of recent transmission. More than half (52%) of U.S.-born cases resulted from recent transmission. Among the U.S.-born, recent transmission was predicted by both individual- and neighborhood-level sociodemographic characteristics. Interventions aimed at reducing TB incidence among foreign-born should focus on reducing reactivation of latent infection. However, reducing TB incidence among the U.S.-born will require decreasing transmission among socially disadvantaged groups at the individual- and neighborhood- levels. This report fills an important knowledge gap regarding the contemporary social context of TB in the United States, thereby providing a foundation for future studies of public health policies that can lead to the development of more targeted, effective TB control. Copyright © 2017 Elsevier Inc. All rights reserved.

Acculturation and Maternal Health Behaviors

PubMed Central

Hawkins, Summer Sherburne; Gillman, Matthew W.; Shafer, Emily F.; Cohen, Bruce B.

2014-01-01

Background Although prior studies have shown disparities in maternal health behaviors according to race/ethnicity and acculturation, whether these patterns are evident among new immigrant populations remains unclear. Purpose To examine the associations among proxies of acculturation and maternal smoking during pregnancy and breastfeeding initiation within each major ethnic group in Massachusetts. Methods Data were from the Standard Certificate of Live Births on 1,067,375 babies by mothers from 31 ethnic groups for 1996–2009. Mothers reported whether they smoked during pregnancy and the birth facility recorded whether mothers started breastfeeding. The acculturation proxy combined mothers’ country of birth and language preference: U.S.-born, foreign-born English-speaking, and foreign-born non-English speaking. For each ethnic group, adjusted logistic regression models were conducted to examine associations between the acculturation proxy and whether mothers smoked or initiated breastfeeding. Data were analyzed from 2012 to 2013. Results A lower proportion of foreign-born mothers had a high school degree or private insurance than U.S.-born mothers. However, foreign-born mothers who were English (range of AORs=0.07–0.93) or non-English speakers (AORs=0.01–0.36) were less likely to smoke during pregnancy than their U.S.-born counterparts. Foreign-born mothers who were English (AORs=1.22–6.52) or non-English speakers (AORs=1.35–10.12) were also more likely to initiate breastfeeding compared to U.S.-born mothers, except for some mothers with Asian ethnicities. Conclusions The consistency of the associations of being foreign-born with less smoking and more breastfeeding suggests that for the majority of ethnic groups studied, acculturation in the U.S. results in poorer maternal health behaviors. PMID:24951043

Immigrant children's reliance on public health insurance in the wake of immigration reform.

PubMed

Pati, Susmita; Danagoulian, Shooshan

2008-11-01

We sought to determine whether the reversal of the public charge rule of the Illegal Immigration Reform and Immigrant Responsibility Act, which may have required families to pay for benefits previously received at no cost, led to immigrant children becoming increasingly reliant on public health insurance programs. We conducted a secondary data analysis focusing on low-income children sampled in the 1997 through 2004 versions of the National Health Interview Survey. Between 1997 and 2004, public health insurance enrollments and the numbers of uninsured foreign-born children in the United States increased by 3.1% and 2.7%, respectively. Using multinomial logistic regression models to account for the substantial differences in socioeconomic status between foreign-born and US-born children, we found that low-income US-born children were just as likely as foreign-born children to have public health insurance coverage (odds ratio [OR] = 1.16; 95% confidence interval [CI] = 0.89, 1.52) and that, after 2000, foreign-born children were 1.59 times (95% CI = 1.24, 2.05) more likely than were US-born children to be uninsured (vs publicly insured). In the wake of the reversal of the public charge rule, immigrant children are increasingly likely to be uninsured as opposed to relying on public health insurance.

Cohort Differences in Cognitive Aging in the Longitudinal Aging Study Amsterdam.

PubMed

Brailean, Anamaria; Huisman, Martijn; Prince, Martin; Prina, A Matthew; Deeg, Dorly J H; Comijs, Hannie

2016-09-30

This study aims to examine cohort differences in cognitive performance and rates of change in episodic memory, processing speed, inductive reasoning, and general cognitive performance and to investigate whether these cohort effects may be accounted for by education attainment. The first cohort (N = 705) was born between 1920 and 1930, whereas the second cohort (N = 646) was born between 1931 and 1941. Both birth cohorts were aged 65 to 75 years at baseline and were followed up 3 and 6 years later. Data were analyzed using linear mixed models. The later born cohort had better general cognitive performance, inductive reasoning, and processing speed at baseline, but cohort differences in inductive reasoning and general cognitive performance disappeared after adjusting for education. The later born cohort showed steeper decline in processing speed. Memory decline was steeper in the earlier born cohort but only from Time 1 to Time 3 when the same memory test was administered. Education did not account for cohort differences in cognitive decline. The later born cohort showed better initial performance in certain cognitive abilities, but no better preservation of cognitive abilities overtime compared with the earlier born cohort. These findings carry implications for healthy cognitive aging. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America.

Long-term in vivo single-cell tracking reveals the switch of migration patterns in adult-born juxtaglomerular cells of the mouse olfactory bulb

PubMed Central

Liang, Yajie; Li, Kaizhen; Riecken, Kristoffer; Maslyukov, Anatoliy; Gomez-Nicola, Diego; Kovalchuk, Yury; Fehse, Boris; Garaschuk, Olga

2016-01-01

The behavior of adult-born cells can be easily monitored in cell culture or in lower model organisms, but longitudinal observation of individual mammalian adult-born cells in their native microenvironment still proves to be a challenge. Here we have established an approach named optical cell positioning system for long-term in vivo single-cell tracking, which integrates red-green-blue cell labeling with repeated angiography. By combining this approach with in vivo two-photon imaging technique, we characterized the in vivo migration patterns of adult-born neurons in the olfactory bulb. In contrast to the traditional view of mere radial migration of adult-born cells within the bulb, we found that juxtaglomerular cells switch from radial migration to long distance lateral migration upon arrival in their destination layer. This unique long-distance lateral migration has characteristic temporal (stop-and-go) and spatial (migratory, unidirectional or multidirectional) patterns, with a clear cell age-dependent decrease in the migration speed. The active migration of adult-born cells coincides with the time period of initial fate determination and is likely to impact on the integration sites of adult-born cells, their odor responsiveness, as well as their survival rate. PMID:27174051

Immigrant Children's Reliance on Public Health Insurance in the Wake of Immigration Reform

PubMed Central

Danagoulian, Shooshan

2008-01-01

Objectives. We sought to determine whether the reversal of the public charge rule of the Illegal Immigration Reform and Immigrant Responsibility Act, which may have required families to pay for benefits previously received at no cost, led to immigrant children becoming increasingly reliant on public health insurance programs. Methods. We conducted a secondary data analysis focusing on low-income children sampled in the 1997 through 2004 versions of the National Health Interview Survey. Results. Between 1997 and 2004, public health insurance enrollments and the numbers of uninsured foreign-born children in the United States increased by 3.1% and 2.7%, respectively. Using multinomial logistic regression models to account for the substantial differences in socioeconomic status between foreign-born and US-born children, we found that low-income US-born children were just as likely as foreign-born children to have public health insurance coverage (odds ratio [OR] = 1.16; 95% confidence interval [CI] = 0.89, 1.52) and that, after 2000, foreign-born children were 1.59 times (95% CI = 1.24, 2.05) more likely than were US-born children to be uninsured (vs publicly insured). Conclusions. In the wake of the reversal of the public charge rule, immigrant children are increasingly likely to be uninsured as opposed to relying on public health insurance. PMID:18799772

Uncertainties in energy reconstruction of cosmic rays for ANITA III caused by differences in models of radio emission in atmospheric showers

NASA Astrophysics Data System (ADS)

Bugaev, Viatcheslav; Rauch, Brian; Schoorlemmer, Harm; Lam, Joe; Urdaneta, David; Wissel, Stephanie; Belov, Konstantin; Romero-Wolf, Andrew; Anita Collaboration

2015-04-01

The third flight of the high-altitude balloon-borne Antarctic Impulsive Transient Antenna (ANITA III) was launched on a high-altitude balloon from McMurdo, Antarctica on December 17th, 2014 and flew for 22 days. It was optimized for the measurement of impulsive radio signals from the charged component of extensive air showers initiated by ultra-high energy cosmic rays in the frequency range ~ 180 - 1200 MHz. In addition it is designed to detect radio impulses initiated by high-energy neutrinos interacting in the Antarctic ice, which was the primary objective of the first two ANITA flights. Based on an extensive set of Monte Carlo simulations of radio emissions from cosmic rays (CR) with the ZHAireS and CoREAS simulation packages, we estimate uncertainties in the electric fields at the payload due to different models used in the two packages. The uncertainties in the emission are then propagated through an algorithm for energy reconstruction of individual CR showers to assess uncertainties in the energy reconstruction. We also discuss optimization of this algorithm. This research is supported by NASA under Grant # NNX11AC49G.

Molecular dynamics studies of simple membrane-water interfaces: Structure and functions in the beginnings of cellular life

NASA Technical Reports Server (NTRS)

Pohorille, Andrew; Wilson, Michael A.

1995-01-01

Molecular dynamics computer simulations of the structure and functions of a simple membrane are performed in order to examine whether membranes provide an environment capable of promoting protobiological evolution. Our model membrane is composed of glycerol 1-monooleate. It is found that the bilayer surface fluctuates in time and space, occasionally creating thinning defects in the membrane. These defects are essential for passive transport of simple ions across membranes because they reduce the Born barrier to this process by approximately 40%. Negative ions are transferred across the bilayer more readily than positive ions due to favorable interactions with the electric field at the membrane-water interface. Passive transport of neutral molecules is, in general, more complex than predicted by the solubility-diffusion model. In particular, molecules which exhibit sufficient hydrophilicity and lipophilicity concentrate near membrane surfaces and experience 'interfacial resistance' to transport. The membrane-water interface forms an environment suitable for heterogeneous catalysis. Several possible mechanisms leading to an increase of reaction rates at the interface are discussed. We conclude that vesicles have many properties that make them very good candidates for earliest protocells. Some potentially fruitful directions of experimental and theoretical research on this subject are proposed.

An experimental investigation of mesospheric ionization

NASA Technical Reports Server (NTRS)

Mitchell, J. D.

1973-01-01

Mesospheric ionization and its variability are examined. Data were obtained primarily by the parachute-borne blunt probe technique conducted in coordinated rocket experiments at White Sands Missile Range, New Mexico and Wallops Island, Virginia. Electrical conductivity measurements and deduced charge density values from ten rocket launches are presented and discussed. Positive ion conductivity and electron density were found to be relatively invariant with height between 45 and 60 km. Variations in positive conductivity of a factor of two and enhancements in negative conductivity by as much as a factor of four were measured by the blunt probe. A simple lumped parameter ion chemistry model is shown to satisfactorily explain the charge density values for the undisturbed lower D-region. Implications of the data in terms of this model are considered. The principal loss mechanism for positive ions in the 45 to 60 km. region is concluded to be dissociative recombination. Electron densities deduced from the conductivity data are explained by detachment involving a minor neutral constituent which is mixed between 65 and 45 km. and then cuts off sharply below 45 km. A correlation study involving blunt probe measurements shows relatively good agreement between variations in positive conductivity and temperature.

Measurements of fireball onset

NASA Astrophysics Data System (ADS)

Scheiner, Brett; Barnat, Edward V.; Baalrud, Scott D.; Hopkins, Matthew M.; Yee, Benjamin T.

2018-04-01

Laser-based measurements of the characteristic features of fireball onset and stabilization in response to a stepped voltage applied to an anode immersed in a low pressure (100 mTorr) helium afterglow are reported. These include spatial and temporal evolution of metastable species, electron density, and electric field magnitude as measured by planar laser induced fluorescence, laser-collision induced fluorescence, and laser-induced fluorescence-dip spectroscopy, respectively. These measurements are found to be in qualitative agreement with recent particle-in-cell simulations and theoretical models [Scheiner et al., Phys. Plasmas 24, 113520 (2017)]. The measurements validate the simulations and models in which fireball onset was predicted to follow from the trapping of electrons born from electron impact ionization within a potential well created by a buildup of ions in the sheath. The experimental measurements also demonstrate transient features following the onset that were not present in previous simulations. New simulation results are presented which demonstrate that these features are associated with the abruptness of the voltage step used to initiate fireball onset. An abrupt step in the anode bias causes rapid displacement of ions and an associated plasma potential response following the sheath and fireball expansion.

High cancer mortality for US-born Latinos: evidence from California and Texas.

PubMed

Pinheiro, Paulo S; Callahan, Karen E; Gomez, Scarlett Lin; Marcos-Gragera, Rafael; Cobb, Taylor R; Roca-Barcelo, Aina; Ramirez, Amelie G

2017-07-11

Latinos born in the US, 36 million, comprise 65% of all US Latinos. Yet their cancer experience is nearly always analyzed together with their foreign-born counterparts, 19 million, who constitute a steady influx of truly lower-risk populations from abroad. To highlight specific cancer vulnerabilities for US-born Latinos, we compare their cancer mortality to the majority non-Latino white (NLW) population, foreign-born Latinos, and non-Latino blacks. We analyzed 465,751 cancer deaths from 2008 to 2012 occurring among residents of California and Texas, the two most populous states, accounting for 47% of US Latinos. This cross-sectional analysis, based on granular data obtained from death certificates on cause of death, age, race, ethnicity and birthplace, makes use of normal standardization techniques and negative binomial regression models. While Latinos overall have lower all-cancers-combined mortality rates than NLWs, these numbers were largely driven by low rates among the foreign born while mortality rates for US-born Latinos approach those of NLWs. Among Texas males, rates were 210 per 100,000 for NLWs and 166 for Latinos combined, but 201 per 100,000 for US-born Latinos and 125 for foreign-born Latinos. Compared to NLWs, US-born Latino males in California had mortality rate ratios of 2.83 (95% CI: 2.52-3.18) for liver cancer, 1.44 (95% CI: 1.30-1.61) for kidney cancer, and 1.25 (95% CI: 1.17-1.34) for colorectal cancer (CRC). Texas results showed a similar site-specific pattern. Specific cancer patterns for US-born Latinos, who have relatively high cancer mortality, similar overall to NLWs, are masked by aggregation of all Latinos, US-born and foreign-born. While NLWs had high mortality for lung cancer, US-born Latinos had high mortality for liver, kidney and male colorectal cancers. HCV testing and reinforcement of the need for CRC screening should be a priority in this specific and understudied population. The unprecedented proximity of overall rates between NLWs and US-born Latino populations runs counter to the prevailing narrative of Latinos having significantly lower cancer risk and mortality. Birthplace data are critical in detecting meaningful differences among Latinos; these findings merit not only clinical but also public health attention.

Where are you from? A validation of the Foreigner Objectification Scale and the psychological correlates of foreigner objectification among Asian Americans and Latinos.

PubMed

Armenta, Brian E; Lee, Richard M; Pituc, Stephanie T; Jung, Kyoung-Rae; Park, Irene J K; Soto, José A; Kim, Su Yeong; Schwartz, Seth J

2013-04-01

Many ethnic minorities in the United States consider themselves to be just as American as their European American counterparts. However, there is a persistent cultural stereotype of ethnic minorities as foreigners (i.e., the perpetual foreigner stereotype) that may be expressed during interpersonal interactions (i.e., foreigner objectification). The goal of the present study was to validate the Foreigner Objectification Scale, a brief self-report measure of perceived foreigner objectification, and to examine the psychological correlates of perceived foreigner objectification. Results indicated that the Foreigner Objectification Scale is structurally (i.e., factor structure) and metrically (i.e., factor loadings) invariant across foreign-born and U.S.-born Asian Americans and Latinos. Scalar (i.e., latent item intercepts) invariance was demonstrated for the two foreign-born groups and the two U.S.-born groups, but not across foreign-born and U.S.-born individuals. Multiple-group structural equation models indicated that, among U.S.-born individuals, perceived foreigner objectification was associated with less life satisfaction and more depressive symptoms, and was indirectly associated with lower self-esteem via identity denial, operationalized as the perception that one is not viewed by others as American. Among foreign-born individuals, perceived foreigner objectification was not significantly associated directly with self-esteem, life satisfaction, or depressive symptoms. However, perceived foreigner objectification was positively associated with identity denial, and identity denial was negatively associated with life satisfaction. This study illustrates the relevance of perceived foreigner objectification to the psychological well-being of U.S.-born Asian Americans and Latinos.

Healthy weight advantage lost in one generation among immigrant elementary schoolchildren in multi-ethnic, disadvantaged, inner-city neighborhoods in Montreal, Canada.

PubMed

Maximova, Katerina; O'Loughlin, Jennifer; Gray-Donald, Katherine

2011-04-01

We sought to determine if the rate of increase in body mass index (BMI) differs between first generation immigrant children (child and both parents born outside Canada); second generation immigrant children (child born in Canada with at least one parent born outside Canada); and native-born children (child and both parents born in Canada), and if the rate of increase varies across ethnic groups. Data were available from the evaluation of a 5-year heart health promotion program targeted to elementary school children from 24 schools in multi-ethnic, disadvantaged, inner-city neighborhoods in Montreal, Canada. Participants were 6392 children aged 9-12 years born in and outside of Canada. Height and weight were measured annually according to a standardized protocol. BMI increases with age were examined using individual growth models stratified by immigrant status grouping (first generation immigrant, second generation immigrant, native-born). On average, BMI increased by 0.59, 0.73, and 0.82 kg/m2 with each year of age among first generation immigrant, second generation immigrant, and native-born children, respectively. These differences held across four family origin grouping (Europe, Asia, Central/South America, and Other). The protective effect of immigrant status on BMI increases with age dissipated in second generation immigrant children, whose rate of increase was similar to that of native-born children. Because immigrants constitute the fastest growing segment of the Canadian population, it is important to understand the causes of the higher BMI increases with successive generations. Copyright © 2011 Elsevier Inc. All rights reserved.

Language functions in preterm-born children: a systematic review and meta-analysis.

PubMed

van Noort-van der Spek, Inge L; Franken, Marie-Christine J P; Weisglas-Kuperus, Nynke

2012-04-01

Preterm-born children (<37 weeks' gestation) have higher rates of language function problems compared with term-born children. It is unknown whether these problems decrease, deteriorate, or remain stable over time. The goal of this research was to determine the developmental course of language functions in preterm-born children from 3 to 12 years of age. Computerized databases Embase, PubMed, Web of Knowledge, and PsycInfo were searched for studies published between January 1995 and March 2011 reporting language functions in preterm-born children. Outcome measures were simple language function assessed by using the Peabody Picture Vocabulary Test and complex language function assessed by using the Clinical Evaluation of Language Fundamentals. Pooled effect sizes (in terms of Cohen's d) and 95% confidence intervals (CI) for simple and complex language functions were calculated by using random-effects models. Meta-regression was conducted with mean difference of effect size as the outcome variable and assessment age as the explanatory variable. Preterm-born children scored significantly lower compared with term-born children on simple (d = -0.45 [95% CI: -0.59 to -0.30]; P < .001) and on complex (d = -0.62 [95% CI: -0.82 to -0.43]; P < .001) language function tests, even in the absence of major disabilities and independent of social economic status. For complex language function (but not for simple language function), group differences between preterm- and term-born children increased significantly from 3 to 12 years of age (slope = -0.05; P = .03). While growing up, preterm-born children have increasing difficulties with complex language function.

A numerical analysis of the Born approximation for image formation modeling of differential interference contrast microscopy for human embryos

NASA Astrophysics Data System (ADS)

Trattner, Sigal; Feigin, Micha; Greenspan, Hayit; Sochen, Nir

2008-03-01

The differential interference contrast (DIC) microscope is commonly used for the visualization of live biological specimens. It enables the view of the transparent specimens while preserving their viability, being a non-invasive modality. Fertility clinics often use the DIC microscope for evaluation of human embryos quality. Towards quantification and reconstruction of the visualized specimens, an image formation model for DIC imaging is sought and the interaction of light waves with biological matter is examined. In many image formation models the light-matter interaction is expressed via the first Born approximation. The validity region of this approximation is defined in a theoretical bound which limits its use to very small specimens with low dielectric contrast. In this work the Born approximation is investigated via the Helmholtz equation, which describes the interaction between the specimen and light. A solution on the lens field is derived using the Gaussian Legendre quadrature formulation. This numerical scheme is considered both accurate and efficient and has shortened significantly the computation time as compared to integration methods that required a great amount of sampling for satisfying the Whittaker - Shannon sampling theorem. By comparing the numerical results with the theoretical values it is shown that the theoretical bound is not directly relevant to microscopic imaging and is far too limiting. The numerical exhaustive experiments show that the Born approximation is inappropriate for modeling the visualization of thick human embryos.

Past and future perspectives on mathematical models of tick-borne pathogens.

PubMed

Norman, R A; Worton, A J; Gilbert, L

2016-06-01

Ticks are vectors of pathogens which are important both with respect to human health and economically. They have a complex life cycle requiring several blood meals throughout their life. These blood meals take place on different individual hosts and potentially on different host species. Their life cycle is also dependent on environmental conditions such as the temperature and habitat type. Mathematical models have been used for the more than 30 years to help us understand how tick dynamics are dependent on these environmental factors and host availability. In this paper, we review models of tick dynamics and summarize the main results. This summary is split into two parts, one which looks at tick dynamics and one which looks at tick-borne pathogens. In general, the models of tick dynamics are used to determine when the peak in tick densities is likely to occur in the year and how that changes with environmental conditions. The models of tick-borne pathogens focus more on the conditions under which the pathogen can persist and how host population densities might be manipulated to control these pathogens. In the final section of the paper, we identify gaps in the current knowledge and future modelling approaches. These include spatial models linked to environmental information and Geographic Information System maps, and development of new modelling techniques which model tick densities per host more explicitly.

Can Horton hear the whos? The importance of scale in mosquito-borne disease.

PubMed

Lord, C C; Alto, B W; Anderson, S L; Connelly, C R; Day, J F; Richards, S L; Smartt, C T; Tabachnick, W J

2014-03-01

The epidemiology of vector-borne pathogens is determined by mechanisms and interactions at different scales of biological organization, from individual-level cellular processes to community interactions between species and with the environment. Most research, however, focuses on one scale or level with little integration between scales or levels within scales. Understanding the interactions between levels and how they influence our perception of vector-borne pathogens is critical. Here two examples of biological scales (pathogen transmission and mosquito mortality) are presented to illustrate some of the issues of scale and to explore how processes on different levels may interact to influence mosquito-borne pathogen transmission cycles. Individual variation in survival, vector competence, and other traits affect population abundance, transmission potential, and community structure. Community structure affects interactions between individuals such as competition and predation, and thus influences the individual-level dynamics and transmission potential. Modeling is a valuable tool to assess interactions between scales and how processes at different levels can affect transmission dynamics. We expand an existing model to illustrate the types of studies needed, showing that individual-level variation in viral dose acquired or needed for infection can influence the number of infectious vectors. It is critical that interactions within and among biological scales and levels of biological organization are understood for greater understanding of pathogen transmission with the ultimate goal of improving control of vector-borne pathogens.

Is an index of co-occurring unhealthy lifestyles suitable for understanding migrant health?

PubMed

Feng, Xiaoqi; Astell-Burt, Thomas; Kolt, Gregory S

2014-12-01

This study investigated variation in unhealthy lifestyles within Australia according to where people were born. Multilevel linear regression models were used to explore variation in co-occurring unhealthy lifestyles (from 0 to 8) constructed from responses to tobacco smoking, alcohol consumption, moderate-to-vigorous physical activity and a range of dietary indicators for 217,498 adults born in 22 different countries now living in Australia. Models were adjusted for socio-economic variables. Data was from the 45 and Up Study (2006-2009). Further analyses involved multilevel logistic regression to examine country-of-birth patterning of each individual unhealthy lifestyle. Small differences in the co-occurrence of unhealthy lifestyles were observed by country of birth, ranging from 3.1 (Philippines) to 3.8 (Russia). More substantial variation was observed for each individual unhealthy lifestyle. Smoking and alcohol ranged from 7.3% and 4.2% (both China) to 28.5% (Lebanon) and 30.8% (Ireland) respectively. Non-adherence to physical activity guidelines was joint-highest among participants born in Japan and China (both 74.5%), but lowest among those born in Scandinavian countries (52.5%). Substantial variation in meeting national dietary guidelines was also evident between participants born in different countries. The growing trend for constructing unhealthy lifestyle indices can hide important variation in individual unhealthy lifestyles by country of birth. Copyright © 2014. Published by Elsevier Inc.

The Generalized Born solvation model: What is it?

NASA Astrophysics Data System (ADS)

Onufriev, Alexey

2004-03-01

Implicit solvation models provide, for many applications, an effective way of describing the electrostatic effects of aqueous solvation. Here we outline the main approximations behind the popular Generalized Born solvation model. We show how its accuracy, relative to the Poisson-Boltzmann treatment, can be significantly improved in a computationally inexpensive manner to make the model useful in the studies of large-scale conformational transitions at the atomic level. The improved model is tested in a molecular dynamics simulation of folding of a 46-residue (three helix bundle) protein. Starting from an extended structure at 450K, the protein folds to the lowest energy conformation within 6 ns of simulation time, and the predicted structure differs from the native one by 2.4 A (backbone RMSD).

Runoff delay exerts a strong control on the field-scale removal of manure-borne fecal bacteria with runoff

USDA-ARS?s Scientific Manuscript database

The microbial safety of surface waters is an ongoing issue which is threatened by the transport of manure-borne bacteria to water sources used for irrigation or recreation. Predictive modeling has become an effective tool to forecast the microbial quality of water during precipitation events, howeve...

Protective and Risk Influences of Drug Use among a Multiethnic Sample of Adolescent Boys

ERIC Educational Resources Information Center

Galaif, E. R.; Newcomb, M. D.; Vega, W. A.; Krell, R. D.

2007-01-01

A measurement model was analyzed to demonstrate a differential distribution and cumulative exposure to psychosocial risk and protective influences of adolescent drug use among ethnically-diverse adolescent samples. The sample included U.S.-born (US) Latino (N = 837), foreign-born (FB) Latino (N = 447), White (N = 632), and African American (N =…

Improving Children's Life Chances: Estimates from the Social Genome Model

ERIC Educational Resources Information Center

Grannis, Kerry Searle; Sawhill, Isabel

2013-01-01

There is ample evidence that children born to poorer families do not succeed at the same rate as children born to the middle class. On average, low-income children lag behind on almost every cognitive, behavioral, emotional, and health measure. These gaps start early--some of the newest research suggests that cognitive gaps are detectable in…

TRACE METAL LEACHING BEHAVIOR STUDIED THROUGH THE USE OF PARAMETRIC MODELING OF WATER BORNE SOIL PARTICLES FRACTIONATED WITH A SPLIT-FLOW THIN CELL

EPA Science Inventory

Removal of pollutant-laden particles via engineered structures such as settling ponds is one goal of storm water management. Leaching of metals as a function of particle size affects the ability of settling ponds to remoe the polluted particle. In this investigation, water borne ...

Transmission bottlenecks and RNAi collectively influence tick-borne flavivirus evolution.

PubMed

Grubaugh, Nathan D; Rückert, Claudia; Armstrong, Philip M; Bransfield, Angela; Anderson, John F; Ebel, Gregory D; Brackney, Doug E

2016-07-01

Arthropod-borne RNA viruses exist within hosts as heterogeneous populations of viral variants and, as a result, possess great genetic plasticity. Understanding the micro-evolutionary forces shaping these viruses can provide insights into how they emerge, adapt, and persist in new and changing ecological niches. While considerable attention has been directed toward studying the population dynamics of mosquito-borne viruses, little is known about tick-borne virus populations. Therefore, using a mouse and Ixodes scapularis tick transmission model, we examined Powassan virus (POWV; Flaviviridae, Flavivirus ) populations in and between both the vertebrate host and arthropod vector. We found that genetic bottlenecks, RNAi-mediated diversification, and selective constraints collectively influence POWV evolution. Together, our data provide a mechanistic explanation for the slow, long-term evolutionary trends of POWV, and suggest that all arthropod-borne viruses encounter similar selective pressures at the molecular level (i.e. RNAi), yet evolve much differently due to their unique rates and modes of transmission.

Height of Northern Jordanian middle-class adults, born 1960-1990 in the response to improving socio-economic conditions.

PubMed

Abu Dalou, Ahmad Yosuf

2016-09-01

The purpose of this study is to document and explain secular trends in stature among Northern Jordanian men and women between the years of birth 1960 and 1990, as they relate to overall per capita socio-economic improvement, the stature of 360 adults from two Northern governorates, those of Jerash and Irbid, was measured. General linear model (GLM) was used to examine the effect of birth-decade, education level of subject, and their interaction on mean stature of each sex separately. GLM results revealed that women who were born during the following three decades pooled together (1951-1980) did not differ significantly in mean stature from those born during (1981-1990). Among men, stature of those born in the two pooled birth-decades together (1951-1970) did not significantly differ of those were born in the two pooled birth-decades (1971-1990). Copyright © 2016. Published by Elsevier B.V.

Comparative study of generalized born models: Born radii and peptide folding.

PubMed

Zhu, Jiang; Alexov, Emil; Honig, Barry

2005-02-24

In this study, we have implemented four analytical generalized Born (GB) models and investigated their performance in conjunction with the GROMOS96 force field. The four models include that of Still and co-workers, the HCT model of Cramer, Truhlar, and co-workers, a modified form of the AGB model of Levy and co-workers, and the GBMV2 model of Brooks and co-workers. The models were coded independently and implemented in the GROMOS software package and in TINKER. They were compared in terms of their ability to reproduce the results of Poisson-Boltzmann (PB) calculations and in their performance in the ab initio peptide folding of two peptides, one that forms a beta-hairpin in solution and one that forms an alpha-helix. In agreement with previous work, the GBMV2 model is most successful in reproducing PB results while the other models tend to underestimate the effective Born radii of buried atoms. In contrast, stochastic dynamics simulations on the folding of the two peptides, the C-terminus beta-hairpin of the B1 domain of protein G and the alanine-based alpha-helical peptide 3K(I), suggest that the simpler GB models are more effective in sampling conformational space. Indeed, the Still model used in conjunction with the GROMOS96 force field is able to fold the hairpin peptide to a native-like structure without the benefit of enhanced sampling techniques. This is due in part to the properties of the united-atom GROMOS96 force field which appears to be more flexible, and hence to sample more efficiently, than force fields such as OPLSAA. Our results suggest a general strategy which involves using different combinations of force fields and solvent models in different applications, for example, using GROMOS96 and a simple GB model in sampling and OPLSAA and a more accurate GB model in refinement. The fact that various methods have been implemented in a unified way should facilitate the testing and subsequent use of different methods to evaluate conformational free energies in different applications. Our results also bear on some general issues involved in peptide folding and structure prediction which are addressed in the Discussion.

Predictors of breastfeeding initiation in Hong Kong and Mainland China born mothers.

PubMed

Lok, Kris Yuet Wan; Bai, Dorothy Li; Tarrant, Marie

2015-11-03

In recent years there has been a steady influx of immigrants into Hong Kong from Mainland China, where breastfeeding patterns differ. Studies in other regions have found substantial differences in breastfeeding rates between native-born and immigrant mothers. The purpose of this study was to examine factors associated with breastfeeding initiation in Hong Kong born and Mainland China born mothers living in Hong Kong. We used a multi-center cross-sectional study design and recruited 2761 new mothers from the postnatal wards of all eight public hospitals in Hong Kong that offer obstetric services. We assessed breastfeeding status as well as various socio-demographic, maternal and birth characteristics. Chi-square tests and multivariable logistic regression were used to identify the predictors of breastfeeding initiation in Hong Kong born and Mainland China born participants. 80.3 % of Hong Kong and 81.1 % of Mainland Chinese born women initiated breastfeeding. In the fully adjusted models, multiparity (Odds Ratio [OR] 0.53, 95 % CI 0.43-0.66) and maternal smoking (OR 0.29, 95 % CI 0.18-0.45) were strongly associated with failure to initiate breastfeeding in both Hong Kong and Mainland China born participants. In Hong Kong born mothers, participants with lower maternal education and those who had a cesarean section were significantly less likely to breastfeed. For Mainland China born mothers, paternal smoking (OR 0.70, 95 % CI 0.49-0.99) and having a pregnancy-related health problem (OR 0.60, 95 % CI 0.38-0.94) were both additional risk factors for not breastfeeding. This study has identified predictors of breastfeeding initiation in Hong Kong and Mainland China born mothers. Given the current high breastfeeding initiation rates among both groups, antenatal breastfeeding education and promotion programmes need to specifically intervene with sub-groups of pregnant women at risk for not breastfeeding so that their efforts are more strategic and cost-effective.

Health impacts of large dams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lerer, L.B.; Scudder, T.

1999-03-01

Large dams have been criticized because of their negative environmental and social impacts. Public health interest largely has focused on vector-borne diseases, such as schistosomiasis, associated with reservoirs and irrigation projects. Large dams also influence health through changes in water and food security, increases in communicable diseases, and the social disruption caused by construction and involuntary resettlement. Communities living in close proximity to large dams often do not benefit from water transfer and electricity generation revenues. A comprehensive health component is required in environmental and social impact assessments for large dam projects.

Variation in birth outcomes by mother's country of birth among non-Hispanic black women in the United States.

PubMed

Elo, Irma T; Vang, Zoua; Culhane, Jennifer F

2014-12-01

Rates of prematurity (PTB) and small-for-gestational age (SGA) were compared between US-born and foreign-born non-Hispanic black women. Comparisons were also made between Sub-Saharan African-born and Caribbean-born black women and by maternal country of birth within the two regions. Comparisons were adjusted for sociodemographic, health behavioral and medical risk factors available on the birth record. Birth record data (2008) from all states (n = 27) where mother's country of birth was recorded were used. These data comprised 58 % of all singleton births to non-Hispanic black women in that year. Pearson Chi square and logistic regression were used to investigate variation in the rates of PTB and SGA by maternal nativity. Foreign-born non-Hispanic black women had significantly lower rates of PTB (OR 0.727; CI 0. 726, 0.727) and SGA (OR 0.742; CI 0.739-0.745) compared to US-born non-Hispanic black women in a fully adjusted model. Sub-Saharan African-born black women compared to Caribbean-born black women had significantly lower rates of PTB and SGA. Within each region, the rates of PTB and SGA varied by mother's country of birth. These differences could not be explained by adjustment for known risk factors obtained from vital records. Considerable heterogeneity in rates of PTB and SGA among non-Hispanic black women in the US by maternal nativity was documented and remained unexplained after adjustment for known risk factors.

Spatiotemporal Clustering of Mycobacterium tuberculosis Complex Genotypes in Florida: Genetic Diversity Segregated by Country of Birth

PubMed Central

Séraphin, Marie Nancy; Lauzardo, Michael; Morris, J. Glenn; Blackburn, Jason K.

2016-01-01

Background Tuberculosis (TB) is caused by members of the Mycobacterium tuberculosis complex (MTBC). Although the MTBC is highly clonal, between-strain genetic diversity has been observed. In low TB incidence settings, immigration may facilitate the importation of MTBC strains with a potential to complicate TB control efforts. Methods We investigated the genetic diversity and spatiotemporal clustering of 2,510 MTBC strains isolated in Florida, United States, between 2009 and 2013 and genotyped using spoligotyping and 24-locus MIRU-VNTR. We mapped the genetic diversity to the centroid of patient residential zip codes using a geographic information system (GIS). We assessed transmission dynamics and the influence of immigration on genotype clustering using space-time permutation models adjusted for foreign-born population density and county-level HIV risk and multinomial models stratified by country of birth and timing of immigration in SaTScan. Principal Findings Among the 2,510 strains, 1,245 were reported among foreign-born persons; including 408 recent immigrants (<5 years). Strain allelic diversity (h) ranged from low to medium in most locations and was most diverse in urban centers where foreign-born population density was also high. Overall, 21.5% of cases among U.S.-born persons and 4.6% among foreign-born persons clustered genotypically and spatiotemporally and involved strains of the Haarlem family. One Haarlem space-time cluster identified in the mostly rural northern region of Florida included US/Canada-born individuals incarcerated at the time of diagnosis; two clusters in the mostly urban southern region of Florida were composed predominantly of foreign-born persons. Both groups had HIV prevalence above twenty percent. Conclusions/Significance Almost five percent of TB cases reported in Florida during 2009–2013 were potentially due to recent transmission. Improvements to TB screening practices among the prison population and recent immigrants are likely to impact TB control. Due to the monomorphic nature of available markers, whole genome sequencing is needed to conclusively delineate recent transmission events between U.S. and foreign-born persons. PMID:27093156

A survey of basic reproductive ratios in vector-borne disease transmission modeling

NASA Astrophysics Data System (ADS)

Soewono, E.; Aldila, D.

2015-03-01

Vector-borne diseases are commonly known in tropical and subtropical countries. These diseases have contributed to more than 10% of world infectious disease cases. Among the vectors responsible for transmitting the diseases are mosquitoes, ticks, fleas, flies, bugs and worms. Several of the diseases are known to contribute to the increasing threat to human health such as malaria, dengue, filariasis, chikungunya, west nile fever, yellow fever, encephalistis, and anthrax. It is necessary to understand the real process of infection, factors which contribute to the complication of the transmission in order to come up with a good and sound mathematical model. Although it is not easy to simulate the real transmission process of the infection, we could say that almost all models have been developed from the already long known Host-Vector model. It constitutes the main transmission processes i.e. birth, death, infection and recovery. From this simple model, the basic concepts of Disease Free and Endemic Equilibria and Basic Reproductive Ratio can be well explained and understood. Theoretical, modeling, control and treatment aspects of disease transmission problems have then been developed for various related diseases. General construction as well as specific forms of basic reproductive ratios for vector-borne diseases are discusses here.

Design, Implementation, and Operational Methodologies for Sub-arcsecond Attitude Determination, Control, and Stabilization of the Super-pressure Balloon-Borne Imaging Telescope (SuperBIT)

NASA Astrophysics Data System (ADS)

Javier Romualdez, Luis

Scientific balloon-borne instrumentation offers an attractive, competitive, and effective alternative to space-borne missions when considering the overall scope, cost, and development timescale required to design and launch scientific instruments. In particular, the balloon-borne environment provides a near-space regime that is suitable for a number of modern astronomical and cosmological experiments, where the atmospheric interference suffered by ground-based instrumentation is negligible at stratospheric altitudes. This work is centered around the analytical strategies and implementation considerations for the attitude determination and control of SuperBIT, a scientific balloon-borne payload capable of meeting the strict sub-arcsecond pointing and image stability requirements demanded by modern cosmological experiments. Broadly speaking, the designed stability specifications of SuperBIT coupled with its observational efficiency, image quality, and accessibility rivals state-of-the-art astronomical observatories such as the Hubble Space Telescope. To this end, this work presents an end-to-end design methodology for precision pointing balloon-borne payloads such as SuperBIT within an analytical yet implementationally grounded context. Simulation models of SuperBIT are analytically derived to aid in pre-assembly trade-off and case studies that are pertinent to the dynamic balloon-borne environment. From these results, state estimation techniques and control methodologies are extensively developed, leveraging the analytical framework of simulation models and design studies. This pre-assembly design phase is physically validated during assembly, integration, and testing through implementation in real-time hardware and software, which bridges the gap between analytical results and practical application. SuperBIT attitude determination and control is demonstrated throughout two engineering test flights that verify pointing and image stability requirements in flight, where the post-flight results close the overall design loop by suggesting practical improvements to pre-design methodologies. Overall, the analytical and practical results presented in this work, though centered around the SuperBIT project, provide generically useful and implementationally viable methodologies for high precision balloon-borne instrumentation, all of which are validated, justified, and improved both theoretically and practically. As such, the continuing development of SuperBIT, built from the work presented in this thesis, strives to further the potential for scientific balloon-borne astronomy in the near future.

A Biopsychosocial Conceptual Framework of Postpartum Depression Risk in Immigrant and U.S.-born Latina Mothers in the United States.

PubMed

Lara-Cinisomo, Sandraluz; Girdler, Susan S; Grewen, Karen; Meltzer-Brody, Samantha

2016-01-01

In this review, we offer a conceptual framework that identifies risk factors of postpartum depression (PPD) in immigrant and U.S.-born Latinas in the United States by focusing on psychosocial and neuroendocrine factors. Although the evidence of the impact psychosocial stressors have on the development of PPD has been well-documented, less is known about the biological etiology of PPD or how these complex stressors jointly increase the risk of PPD in immigrant and U.S.-born Latinas in the United States. Using PubMed, CINAHL, and Embase, we reviewed the literature from 2000 to 2015 regarding psychosocial and physiological risk factors associated with PPD to develop a conceptual model for Latinas. Our search yielded 16 relevant studies. Based on our review of the literature, we developed a biopsychosocial conceptual model of PPD for Latinas in the United States. We make arguments for an integrated model designed to assess psychosocial and physiological risk factors and PPD in a high-risk population. Our framework describes the hypothesized associations between culturally and contextually relevant psychosocial stressors, neurobiological factors (e.g., hypothalamic-pituitary-adrenal [HPA] axis response system and oxytocin signaling), and PPD in Latinas in the United States. Future studies should evaluate prospectively the impact psychosocial stressors identified here have on the development of PPD in both immigrant and U.S-born Latinas while examining neuroendocrine function, such as the HPA axis and oxytocin signaling. Our conceptual framework will allow for the reporting of main and indirect effects of psychosocial risk factors and biomarkers (e.g., HPA axis and oxytocin function) on PPD in foreign- and U.S.-born postpartum Latinas. Copyright © 2016 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Correction of the near threshold behavior of electron collisional excitation cross-sections in the plane-wave Born approximation

NASA Astrophysics Data System (ADS)

Kilcrease, D. P.; Brookes, S.

2013-12-01

The modeling of NLTE plasmas requires the solution of population rate equations to determine the populations of the various atomic levels relevant to a particular problem. The equations require many cross sections for excitation, de-excitation, ionization and recombination. A simple and computational fast way to calculate electron collisional excitation cross-sections for ions is by using the plane-wave Born approximation. This is essentially a high-energy approximation and the cross section suffers from the unphysical problem of going to zero near threshold. Various remedies for this problem have been employed with varying degrees of success. We present a correction procedure for the Born cross-sections that employs the Elwert-Sommerfeld factor to correct for the use of plane waves instead of Coulomb waves in an attempt to produce a cross-section similar to that from using the more time consuming Coulomb Born approximation. We compare this new approximation with other, often employed correction procedures. We also look at some further modifications to our Born Elwert procedure and its combination with Y.K. Kim's correction of the Coulomb Born approximation for singly charged ions that more accurately approximate convergent close coupling calculations.

Geographic variations of the bird-borne structural risk of West Nile virus circulation in Europe

PubMed Central

Durand, Benoit; Tran, Annelise; Balança, Gilles

2017-01-01

The structural risk of West Nile Disease results from the usual functioning of the socio-ecological system, which may favour the introduction of the pathogen, its circulation and the occurrence of disease cases. Its geographic variations result from the local interactions between three components: (i) reservoir hosts, (ii) vectors, both characterized by their diversity, abundance and competence, (iii) and the socio-economic context that impacts the exposure of human to infectious bites. We developed a model of bird-borne structural risk of West Nile Virus (WNV) circulation in Europe, and analysed the association between the geographic variations of this risk and the occurrence of WND human cases between 2002 and 2014. A meta-analysis of WNV serosurveys conducted in wild bird populations was performed to elaborate a model of WNV seropositivity in European bird species, considered a proxy for bird exposure to WNV. Several eco-ethological traits of bird species were linked to seropositivity and the statistical model adequately fitted species-specific seropositivity data (area under the ROC curve: 0.85). Combined with species distribution maps, this model allowed deriving geographic variations of the bird-borne structural risk of WNV circulation. The association between this risk, and the occurrence of WND human cases across the European Union was assessed. Geographic risk variations of bird-borne structural risk allowed predicting WND case occurrence in administrative districts of the EU with a sensitivity of 86% (95% CI: 0.79–0.92), and a specificity of 68% (95% CI: 0.66–0.71). Disentangling structural and conjectural health risks is important for public health managers as risk mitigation procedures differ according to risk type. The results obtained show promise for the prevention of WND in Europe. Combined with analyses of vector-borne structural risk, they should allow designing efficient and targeted prevention measures. PMID:29023472

Pickup Ions in the Plasma Environments of Mars, Comets, and Enceladus

NASA Astrophysics Data System (ADS)

Cravens, T.; Rahmati, A.; Sakai, S.; Madanian, H.; Larson, D. E.; Lillis, R. J.; Halekas, J. S.; Goldstein, R.; Burch, J. L.; Clark, G. B.; Jakosky, B. M.

2015-12-01

Ions created within a flowing plasma by ionization of neutrals respond to the electric and magnetic fields associated with the flow becoming what are called pick-up ions (PUI). PUI play an important role in many solar system plasma environments and affect the energy and momentum balance of the plasma flow. PUI have been observed during several recent space missions and PUI data will be compared and interpreted using models. Pick-up oxygen ions were observed in the solar wind upstream of Mars by the Solar Energetic Particle (SEP) and Solar Wind Ion Analyzer (SWIA) instruments on NASA's MAVEN (Mars Atmosphere and Volatile EvolutioN) spacecraft. The pick-up oxygen ions are created when atoms in the hot corona are ionized by solar radiation and charge exchange with solar wind protons. The ion fluxes measured by SEP can constrain the oxygen escape rate from Mars. PUI were also been detected at distances of 10 - 100 km from the nucleus of comet 67P/Churyumov- Gerasimenko (67P/CG) by plasma instruments (IES and ICA) onboard the Rosetta Orbiter when the comet was at 3 AU. The newly-born cometary ions are accelerated by the solar wind motional electric field but remain un-magnetized, as suggested by pre-encounter models (Rubin et al., 2014). The inner magnetosphere of Saturn and the water plume of the icy satellite Enceladus provide a third example of PUI. H2O+ ions created by ionization of neutral water producing ions that are picked-up by the co-rotating magnetospheric plasma flow. These ions then undergo a complex interaction with the plume gas including collisions that convert most H2O+ ions to H3O+, as measured by the Ion and Neutral Mass Spectrometer (INMS) onboard the Cassini spacecraft.

Climate Predictors of the Spatial Distribution of Human Plague Cases in the West Nile Region of Uganda

PubMed Central

MacMillan, Katherine; Monaghan, Andrew J.; Apangu, Titus; Griffith, Kevin S.; Mead, Paul S.; Acayo, Sarah; Acidri, Rogers; Moore, Sean M.; Mpanga, Joseph Tendo; Enscore, Russel E.; Gage, Kenneth L.; Eisen, Rebecca J.

2012-01-01

East Africa has been identified as a region where vector-borne and zoonotic diseases are most likely to emerge or re-emerge and where morbidity and mortality from these diseases is significant. Understanding when and where humans are most likely to be exposed to vector-borne and zoonotic disease agents in this region can aid in targeting limited prevention and control resources. Often, spatial and temporal distributions of vectors and vector-borne disease agents are predictable based on climatic variables. However, because of coarse meteorological observation networks, appropriately scaled and accurate climate data are often lacking for Africa. Here, we use a recently developed 10-year gridded meteorological dataset from the Advanced Weather Research and Forecasting Model to identify climatic variables predictive of the spatial distribution of human plague cases in the West Nile region of Uganda. Our logistic regression model revealed that within high elevation sites (above 1,300 m), plague risk was positively associated with rainfall during the months of February, October, and November and negatively associated with rainfall during the month of June. These findings suggest that areas that receive increased but not continuous rainfall provide ecologically conducive conditions for Yersinia pestis transmission in this region. This study serves as a foundation for similar modeling efforts of other vector-borne and zoonotic disease in regions with sparse observational meteorologic networks. PMID:22403328

Neuronal apoptosis in the neonates born to preeclamptic mothers.

PubMed

Cosar, Hese; Ozer, Erdener; Topel, Hande; Kahramaner, Zelal; Turkoglu, Ebru; Erdemir, Aydin; Sutcuoglu, Sumer; Bagriyanik, Alper; Ozer, Esra Arun

2013-07-01

Preeclampsia may result in uteroplacental insufficiency and chronic intrauterine fetal distress. The aim of this study is to address this issue investigating neuronal apoptosis in an experimental model of preeclampsia and to evaluate the neurological outcome of the perinatal asphyxia in the neonates born to preeclamptic mother. Two out of four pregnant Sprague-Dawley rats (preeclamptic group) were given water containing 1.8% NaCl on gestation day 15 and 22 in order to establish the model of preeclampsia whereas other two (non-preeclamptic group) received normal diet. A model of perinatal asphyxia was established on the postnatal 7th day to one preeclamptic and one non-preeclamptic dam. Overall 23 pups born to overall four dams were decapitated to assess neuronal apoptosis by the TUNEL assay. The number of apoptotic neuronal cells was significantly higher in the preeclampsia groups in comparison with the control group (p = 0.006 and p = 0.006, respectively). It was also significantly higher in the asphyctic/non-preeclamptic group than the count in the control group (p = 0.01). There was also significant difference between both asphyctic groups (p = 0.003). We conclude that preeclampsia causes small babies for the gestational age and cerebral hypoplasia. Both preeclampsia and perinatal asphyxia can cause increased neuronal apoptosis in the neonatal brains. However, the prognosis for neurological outcome is much worse when the perinatal asphyxia occurs in newborns born to preeclamptic mothers.

Surveillance of vector-borne pathogens under imperfect detection: lessons from Chagas disease risk (mis)measurement.

PubMed

Minuzzi-Souza, Thaís Tâmara Castro; Nitz, Nadjar; Cuba, César Augusto Cuba; Hagström, Luciana; Hecht, Mariana Machado; Santana, Camila; Ribeiro, Marcelle; Vital, Tamires Emanuele; Santalucia, Marcelo; Knox, Monique; Obara, Marcos Takashi; Abad-Franch, Fernando; Gurgel-Gonçalves, Rodrigo

2018-01-09

Vector-borne pathogens threaten human health worldwide. Despite their critical role in disease prevention, routine surveillance systems often rely on low-complexity pathogen detection tests of uncertain accuracy. In Chagas disease surveillance, optical microscopy (OM) is routinely used for detecting Trypanosoma cruzi in its vectors. Here, we use replicate T. cruzi detection data and hierarchical site-occupancy models to assess the reliability of OM-based T. cruzi surveillance while explicitly accounting for false-negative and false-positive results. We investigated 841 triatomines with OM slides (1194 fresh, 1192 Giemsa-stained) plus conventional (cPCR, 841 assays) and quantitative PCR (qPCR, 1682 assays). Detections were considered unambiguous only when parasitologists unmistakably identified T. cruzi in Giemsa-stained slides. qPCR was >99% sensitive and specific, whereas cPCR was ~100% specific but only ~55% sensitive. In routine surveillance, examination of a single OM slide per vector missed ~50-75% of infections and wrongly scored as infected ~7% of the bugs. qPCR-based and model-based infection frequency estimates were nearly three times higher, on average, than OM-based indices. We conclude that the risk of vector-borne Chagas disease may be substantially higher than routine surveillance data suggest. The hierarchical modelling approach we illustrate can help enhance vector-borne disease surveillance systems when pathogen detection is imperfect.

Ticks and tick-borne pathogens of dogs along an elevational and land-use gradient in Chiriquí province, Panamá.

PubMed

Ferrell, A Michelle; Brinkerhoff, R Jory; Bernal, Juan; Bermúdez, Sergio E

2017-04-01

Systematic acarological surveys are useful tools in assessing risk to tick-borne infections, especially in areas where consistent clinical surveillance for tick-borne disease is lacking. Our goal was to identify environmental predictors of tick burdens on dogs and tick-borne infectious agents in dog-derived ticks in the Chiriquí Province of western Panama to draw inferences about spatio-temporal variation in human risk to tick-borne diseases. We used a model-selection approach to test the relative importance of elevation, human population size, vegetative cover, and change in landuse on patterns of tick parasitism on dogs. We collected 2074 ticks, representing four species (Rhipicephalus sanguineus, R. microplus, Amblyomma ovale, and Ixodes boliviensis) from 355 dogs. Tick prevalence ranged from 0 to 74% among the sites we sampled, and abundance ranged from 0 to 20.4 ticks per dog with R. sanguineus s.l. being the most commonly detected tick species (97% of all ticks sampled). Whereas elevation was the best single determinant of tick prevalence and abundance on dogs, the top models also included predictor variables describing vegetation cover and landuse change. Specifically, low-elevation areas associated with decreasing vegetative cover were associated with highest tick occurrence on dogs, potentially because of the affinity of R. sanguineus for human dwellings. Although we found low prevalence of tick-borne pathogen genera (two Rickettsia-positive ticks, no R. rickettsia or Ehrlichia spp.) in our study, all of the tick species we collected from dogs are known vectors of zoonotic pathogens. In areas where epidemiological surveillance infrastructure is limited, field-based assessments of acarological risk can be useful and cost-effective tools in efforts to identify high-risk environments for tick-transmitted pathogens.

Change in birth outcomes among infants born to Latina mothers after a major immigration raid.

PubMed

Novak, Nicole L; Geronimus, Arline T; Martinez-Cardoso, Aresha M

2017-06-01

Growing evidence indicates that immigration policy and enforcement adversely affect the well-being of Latino immigrants, but fewer studies examine 'spillover effects' on USA-born Latinos. Immigration enforcement is often diffuse, covert and difficult to measure. By contrast, the federal immigration raid in Postville, Iowa, in 2008 was, at the time, the largest single-site federal immigration raid in US history. We employed a quasi-experimental design, examining ethnicity-specific patterns in birth outcomes before and after the Postville raid. We analysed Iowa birth-certificate data to compare risk of term and preterm low birthweight (LBW), by ethnicity and nativity, in the 37 weeks following the raid to the same 37-week period the previous year ( n  =   52 344). We model risk of adverse birth outcomes using modified Poisson regression and model distribution of birthweight using quantile regression. Infants born to Latina mothers had a 24% greater risk of LBW after the raid when compared with the same period 1 year earlier [risk ratio (95% confidence interval) = 1.24 (0.98, 1.57)]. No such change was observed among infants born to non-Latina White mothers. Increased risk of LBW was observed for USA-born and immigrant Latina mothers. The association between raid timing and LBW was stronger among term than preterm births. Changes in birthweight after the raid primarily reflected decreased birthweight below the 5th percentile of the distribution, not a shift in mean birthweight. Our findings highlight the implications of racialized stressors not only for the health of Latino immigrants, but also for USA-born co-ethnics. © The Author 2017; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association

Hispanic Immigrant Father Involvement with Young Children in the United States: A Comparison with US-Born Hispanic and White non-Hispanic Fathers.

PubMed

Guendelman, Sylvia; Nussbaum, Juliet; Soliday, Ann; Lahiff, Maureen

2018-02-14

Objectives Fathering is known to foster child development and health, yet evidence on Hispanic immigrant fathers' involvement with their young children is sparse. This study assessed disparities in pregnancy intendedness and father involvement with children ages 0-4 among Hispanic immigrant co-resident fathers versus two reference groups: US-born Hispanic and US-born White fathers. We hypothesized that differentials in involvement were associated with socioeconomic and cultural factors. Methods Using 2011-2013 data from the National Survey of Family Growth (N = 598), we performed bivariate, logistic and linear regression analyses to assess disparities in pregnancy intendedness and five father involvement outcomes (physical care, warmth, outings, reading and discipline). The models controlled for socio-economic, structural, health and cultural covariates. Results Pregnancy intendedness did not differ significantly between Hispanic immigrant fathers and the two reference groups. Compared with US-born Hispanics, unadjusted models showed that immigrant fathers were less likely to engage in physical care, warmth and reading, (p ≤ 0.05) though the differences were attenuated when controlling for covariates. Hispanic immigrant fathers were less likely than US-born White fathers to engage in each of the father involvement outcomes (p ≤ 0.05), with the disparity in reading to their child persisting even after controlling for all covariates. Conclusions for Practice We found marked socio-economic and cultural differences between Hispanic immigrant and US-born Hispanic and White fathers which contribute to disparities in father involvement with their young children. Hispanic immigrant status is an important determinant of involved fathering and should be taken into account when planning public health policies and programs.

Imbalance between GABAergic and Glutamatergic Transmission Impairs Adult Neurogenesis in an Animal Model of Alzheimer’s Disease

PubMed Central

Sun, Binggui; Halabisky, Brian; Zhou, Yungui; Palop, Jorge J.; Yu, Guiqiu; Mucke, Lennart; Gan, Li

2009-01-01

SUMMARY Adult neurogenesis regulates plasticity and function in the hippocampus, which is critical for memory and vulnerable to Alzheimer’s disease (AD). Promoting neurogenesis may improve hippocampal function in AD brains. However, how amyloid β (Aβ), the key AD pathogen, affects the development and function of adult-born neurons remains unknown. Adult-born granule cells (GCs) in human amyloid precursor protein (hAPP) transgenic mice, an AD model, showed greater dendritic length, spine density, and functional responses than controls early in development, but were impaired morphologically and functionally during later maturation. Early inhibition of GABAA receptors to suppress GABAergic signaling or late inhibition of calcineurin to enhance glutamatergic signaling normalized the development of adult-born GCs in hAPP mice with high Aβ levels. Aβ-induced increases in GABAergic neurotransmission or an imbalance between GABAergic and glutamatergic neurotransmission may contribute to impaired neurogenesis in AD. PMID:19951690

Born Too Soon: What Can We Expect? Nature of Home Literacy Experiences for Children with Very Low Birth Weight

ERIC Educational Resources Information Center

Ragusa, G.

2009-01-01

This study documents the home literacy experiences of children born with very low birth weight (VLBW). The study's design was modelled after Purcell-Gates' study of social domains mediated by print as home literacy experiences. A design combining purposeful sampling, semi-structured data collection and descriptive case study analysis was employed…

Early Reading Achievement of Children in Immigrant Families: Is There an Immigrant Paradox?

ERIC Educational Resources Information Center

Palacios, Natalia; Guttmanova, Katarina; Chase-Lansdale, P. Lindsay

2008-01-01

This article examines whether longitudinal reading trajectories vary by the generational status of immigrant children as they begin formal schooling through the 3rd grade. The results of the hierarchical linear model indicated that 1st and 2nd generation children (i.e., those born in a foreign country and those born in the United States to…

Respiratory morbidity through the first decade of life in a national cohort of children born extremely preterm.

PubMed

Skromme, Kaia; Vollsæter, Maria; Øymar, Knut; Markestad, Trond; Halvorsen, Thomas

2018-03-07

Advances in perinatal care have markedly increased the prospects of survival for infants born extremely preterm (EP). The aim of this study was to investigate hospitalisation rates and respiratory morbidity from five to 11 years of age in a prospective national cohort of EP children born in the surfactant era. This was a national prospective cohort study of all children born in Norway during 1999 and 2000 with gestational age (GA) < 28 weeks or birth weight < 1000 grams, and of individually matched term-born controls recruited for a regional subsample. Data on hospital admissions, respiratory symptoms, and use of asthma medication was obtained by parental questionnaires at 11 years of age. Questionnaires were returned for 232/372 (62%) EP-born and 57/61 (93%) regional term-born controls. Throughout the study period, 67 (29%) EP-born and seven (13%) term-born controls were admitted to hospital (odds ratio (OR) 2.90, 95% confidence interval (CI): 1.25, 6.72). Admissions were mainly due to surgical procedures, with only 12% due to respiratory causes, and were not influenced by neonatal bronchopulmonary dysplasia (BPD) or low GA(≤ 25 weeks). Respiratory symptoms, asthma and use of asthma medication tended to be more common for EP-born, significantly so for medication use and wheeze on exercise. Neonatal BPD was a risk factor for medication use, but not for current wheeze. In multivariate regression models, home oxygen after discharge (OR 4.84, 95% CI: 1.38, 17.06) and parental asthma (OR 4.38, 95% CI: 1.69, 11.38) predicted current asthma, but neither BPD nor low GA were associated with respiratory symptoms at 11 years of age. Hospitalisation rates five to 11 years after EP birth were low, but twice those of term-born controls, and unrelated to neonatal BPD and low GA. Respiratory causes were rare. Respiratory complaints were more common in children born EP, but the burden of symptoms had declined since early childhood.

An electricity consumption model for electric vehicular flow

NASA Astrophysics Data System (ADS)

Xiao, Hong; Huang, Hai-Jun; Tang, Tie-Qiao

2016-09-01

In this paper, we apply the relationships between the macro and micro variables of traffic flow to develop an electricity consumption model for electric vehicular flow. We use the proposed model to study the quantitative relationships between the electricity consumption/total power and speed/density under uniform flow, and the electricity consumptions during the evolution processes of shock, rarefaction wave and small perturbation. The numerical results indicate that the proposed model can perfectly describe the electricity consumption for electric vehicular flow, which shows that the proposed model is reasonable.

Disparities in Chronic Disease Prevalence Among Non-Hispanic Whites: Heterogeneity Among Foreign-Born Arab and European Americans.

PubMed

Dallo, Florence J; Kindratt, Tiffany B

2016-12-01

We estimated and compared the sex- and age-adjusted prevalence of chronic diseases (diagnosis only and comorbidity) among US- and foreign-born whites from Europe and the Arab Nations and examined associations between region of birth and chronic disease. We evaluated 213,644 adults using restricted data from the National Health Interview Survey (2000-2011) by (1) chronic disease diagnosis only (heart disease, asthma, cancer, diabetes, ulcer, or obesity) and (2) comorbidity (none, diagnosis only, comorbid). We used logistic regression to examine associations between region of birth and chronic disease while controlling for confounders. Foreign-born whites from the Arab Nations had a higher prevalence of being diagnosed with ulcer (4 %) compared to US- and European-born whites (2 %). Foreign-born whites from the Arab Nations had a lower prevalence of comorbid cancer (1 %) and ulcer (3 %) yet had higher estimates of comorbid heart disease (18 %), asthma (5 %), and obesity (13 %) when compared to European-born whites (all ps < 0.05). Arab Americans had the highest prevalence of comorbid diabetes (8 %) compared to both European- (5 %) and US-born whites (6 %). In multivariate logistic regression models, Arab Americans had a lower odds of reporting cancer, heart disease, and asthma before and after controlling for covariates. Our study builds on existing literature for Arab Americans as the first study evaluating chronic disease prevalence among foreign-born whites from countries in the Arab League of Nations geographically located in the Middle East. Methodologically robust studies are needed to better understand the influence of acculturation, country of origin, and other characteristics influencing health among foreign-born whites.

Suboptimal care and maternal mortality among foreign-born women in Sweden: maternal death audit with application of the 'migration three delays' model.

PubMed

Esscher, Annika; Binder-Finnema, Pauline; Bødker, Birgit; Högberg, Ulf; Mulic-Lutvica, Ajlana; Essén, Birgitta

2014-04-12

Several European countries report differences in risk of maternal mortality between immigrants from low- and middle-income countries and host country women. The present study identified suboptimal factors related to care-seeking, accessibility, and quality of care for maternal deaths that occurred in Sweden from 1988-2010. A subset of maternal death records (n = 75) among foreign-born women from low- and middle-income countries and Swedish-born women were audited using structured implicit review. One case of foreign-born maternal death was matched with two native born Swedish cases of maternal death. An assessment protocol was developed that applied both the 'migration three delays' framework and a modified version of the Confidential Enquiry from the United Kingdom. The main outcomes were major and minor suboptimal factors associated with maternal death in this high-income, low-maternal mortality context. Major and minor suboptimal factors were associated with a majority of maternal deaths and significantly more often to foreign-born women (p = 0.01). The main delays to care-seeking were non-compliance among foreign-born women and communication barriers, such as incongruent language and suboptimal interpreter system or usage. Inadequate care occurred more often among the foreign-born (p = 0.04), whereas delays in consultation/referral and miscommunication between health care providers where equally common between the two groups. Suboptimal care factors, major and minor, were present in more than 2/3 of maternal deaths in this high-income setting. Those related to migration were associated to miscommunication, lack of professional interpreters, and limited knowledge about rare diseases and pregnancy complications. Increased insight into a migration perspective is advocated for maternity clinicians who provide care to foreign-born women.

Paternal Acculturation and Maternal Health Behaviors: Influence of Father's Ethnicity and Place of Birth.

PubMed

Cheng, Erika R; Taveras, Elsie M; Hawkins, Summer Sherburne

2018-05-01

Studies show disparities in maternal health behaviors according to acculturation, but whether paternal factors influence these patterns is unknown. We assessed the relationships between fathers' ethnicity and place of birth with maternal smoking during pregnancy and breastfeeding initiation overall and for 30 major ethnic groups. Data were from the Standard Certificate of Live Births on 1,053,096 births in Massachusetts between 1996 through 2010. We examined the concordance of maternal and paternal ethnicity and place of birth across three categories (United States-born white, United States-born Other ethnicity, and foreign-born), and then in relation to maternal smoking during pregnancy and breastfeeding initiation. Multivariable models adjusted for maternal age, marital status, education, plurality, parity, prenatal care, delivery source of payment, and year of birth. United States-born white mothers were less likely to smoke during pregnancy (adjusted odds ratio [AOR] 0.66; 95% confidence interval [CI]: 0.60, 0.73) and more likely to initiate breastfeeding (AOR 1.56; 95% CI: 1.46, 1.66) if their partners were foreign-born. In contrast, foreign-born mothers whose partners were United States-born of Other ethnicity or United States-born white had a 1.65-5.12 higher odds of smoking during pregnancy and were 26%-41% less likely (AORs 0.59-0.74) to initiate breastfeeding than if their partners were also foreign-born. Results were consistent across most racial/ethnic groups. Our findings offer new insight into the social pathways by which acculturation impacts maternal health behaviors and add to growing evidence that fathers are valuable to maternal health. Future efforts to understand how acculturation results in poorer maternal health behaviors should account for paternal influences.

Migration and geographic variations in blood pressure in Britain.

PubMed Central

Elford, J; Phillips, A; Thomson, A G; Shaper, A G

1990-01-01

OBJECTIVE--To evaluate the relative contributions of factors acting at different stages in life to regional differences in adult blood pressure. DESIGN--Prospective cohort study (British regional heart study). SETTING--One general practice in each of 24 towns in Britain. SUBJECTS--7735 Men aged 40-59 years when screened in 1978-80 whose geographic zone of birth and zone of examination were classified as south of England, midlands and Wales, north of England, and Scotland. Non-migrants (n = 3144) were born in the town where they were examined; internal migrants (n = 4147) were born in Great Britain but not in the town where they were examined; and international migrants (n = 422) were born outside Great Britain. MAIN OUTCOME MEASURES--Systolic and diastolic blood pressures and height. RESULTS--Regardless of where they were born, men living in the south of England had lower mean blood pressures than men living in Scotland (142.5/80.1 v 148.1/85.2 mm Hg). The effects of the place of birth and place of examination on adult blood pressure were examined in a multiple regression model. For internal migrants the modelled increase in mean systolic blood pressure across adjacent zones of examination was 2.1 mm Hg (95% confidence interval 1.3 to 2.9); for adjacent zones of birth the corresponding increase was 0.1 mm Hg (-0.7 to 0.7). The place of examination seemed to be a far more important determinant of mean adult blood pressure than the place of birth. Height is an accepted marker of genetic and early life influences. Regional differences in height were therefore analysed to test whether the multiple regression model could correctly distinguish between the influence of place of birth and place of examination. As expected, men born in Scotland were shorter on average than men born in the south of England irrespective of where they lived in Britain (172.6 cm v 175.1 cm for internal migrants). CONCLUSION--Regional variations in blood pressure were strongly influenced by where the men had lived for most of their adult lives rather than by where they were born and brought up. Among middle aged men, factors acting in adult life seemed to be more important determinants of regional differences in blood pressure than those acting early in life such as genetic inheritance, intrauterine environment, and childhood experience. PMID:2106957

Birth Origin Differentially Affects Depressive-Like Behaviours: Are Captive-Born Cynomolgus Monkeys More Vulnerable to Depression than Their Wild-Born Counterparts?

PubMed Central

Camus, Sandrine MJ.; Rochais, Céline; Blois-Heulin, Catherine; Li, Qin; Hausberger, Martine; Bezard, Erwan

2013-01-01

Background Adverse early-life experience might lead to the expression of abnormal behaviours in animals and the predisposition to psychiatric disorder (e.g. major depressive disorder) in Humans. Common breeding processes employ weaning and housing conditions different from what happens in the wild. Methods The present study, therefore, investigated whether birth origin impacts the possible existence of spontaneous atypical/abnormal behaviours displayed by 40 captive-born and 40 wild-born socially-housed cynomolgus macaques in farming conditions using an unbiased ethological scan-sampling analysis followed by multifactorial correspondence and hierarchical clustering analyses. Results We identified 10 distinct profiles (groups A to J) that significantly differed on several behaviours, body postures, body orientations, distances between individuals and locations in the cage. Data suggest that 4 captive-born and 1 wild-born animals (groups G and J) present depressive-like symptoms, unnatural early life events thereby increasing the risk of developing pathological symptoms. General differences were also highlighted between the captive- and wild-born populations, implying the expression of differential coping mechanisms in response to the same captive environment. Conclusions Birth origin thus impacts the development of atypical ethologically-defined behavioural profiles, reminiscent of certain depressive-like symptoms. The use of unbiased behavioural observations might allow the identification of animal models of human mental/behavioural disorders and their most appropriate control groups. PMID:23861787

Particle orbits in a force-balanced, wave-driven, rotating torus

DOE PAGES

Ochs, I. E.; Fisch, N. J.

2017-09-01

A wave-driven rotating torus is a recently proposed fusion concept where the rotational transform is provided by the E × B drift resulting from a minor radial electric field. This field can be produced, for instance, by the RF-wave-mediated extraction of fusion-born alpha particles. In this paper, we discuss how macroscopic force balance, i.e., balance of the thermal hoop force, can be achieved in such a device. We show that this requires the inclusion of a small plasma current and vertical magnetic field and identify the desirable reactor regime through free energy considerations. We then analyze particle orbits in thismore » desirable regime, identifying velocity-space anisotropies in trapped (banana) orbits, resulting from the cancellation of rotational transforms due to the radial electric and poloidal magnetic fields. The potential neoclassical effects of these orbits on the perpendicular conductivity, current drive, and transport are discussed.« less

Particle orbits in a force-balanced, wave-driven, rotating torus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ochs, I. E.; Fisch, N. J.

A wave-driven rotating torus is a recently proposed fusion concept where the rotational transform is provided by the E × B drift resulting from a minor radial electric field. This field can be produced, for instance, by the RF-wave-mediated extraction of fusion-born alpha particles. In this paper, we discuss how macroscopic force balance, i.e., balance of the thermal hoop force, can be achieved in such a device. We show that this requires the inclusion of a small plasma current and vertical magnetic field and identify the desirable reactor regime through free energy considerations. We then analyze particle orbits in thismore » desirable regime, identifying velocity-space anisotropies in trapped (banana) orbits, resulting from the cancellation of rotational transforms due to the radial electric and poloidal magnetic fields. The potential neoclassical effects of these orbits on the perpendicular conductivity, current drive, and transport are discussed.« less

Particle orbits in a force-balanced, wave-driven, rotating torus

NASA Astrophysics Data System (ADS)

Ochs, I. E.; Fisch, N. J.

2017-09-01

A wave-driven rotating torus is a recently proposed fusion concept where the rotational transform is provided by the E × B drift resulting from a minor radial electric field. This field can be produced, for instance, by the RF-wave-mediated extraction of fusion-born alpha particles. In this paper, we discuss how macroscopic force balance, i.e., balance of the thermal hoop force, can be achieved in such a device. We show that this requires the inclusion of a small plasma current and vertical magnetic field and identify the desirable reactor regime through free energy considerations. We then analyze particle orbits in this desirable regime, identifying velocity-space anisotropies in trapped (banana) orbits, resulting from the cancellation of rotational transforms due to the radial electric and poloidal magnetic fields. The potential neoclassical effects of these orbits on the perpendicular conductivity, current drive, and transport are discussed.

Nelson Spencer (1918-2002)

NASA Astrophysics Data System (ADS)

Brace, Larry; Carignan, George; Donahue, Tom; Nagy, Andrew; Hunten, Donald

Nelson Spencer, former chief of the Laboratory for Atmospheres at NASA/Goddard Space Flight Center, died on 31 August 2002 in Bethesda, Maryland, at the age of 84 due to complications from Parkinson's disease. He had been an AGU member (SPA) since 1950.He was born in Buffalo, New York, and graduated from the University of Michigan in 1941 with a degree in electrical engineering. Spencer served as a naval officer during World War II and attended Harvard and the Massachusetts Institute of Technology while in the service. After the war, he returned to the University of Michigan for graduate studies, earning his master's degree in electrical engineering in 1953. He soon became director of that department's Space Physics Research Laboratory (SPRL), and later, a full professor. In 1960, Spencer moved to Washington D.C. to lead Goddard's upper atmosphere research effort, serving for many years as chief of the Laboratory for Atmospheres. He retired in 1986.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Young, C.N.

The objectives of the SNAP-7D program were to design, manufacture, test and deliver a thirty-watt electric generating system for a modified U. S. Navy NOMAD-class weather buoy to be stationed in the Gulf of Mexico. The sixty-watt Sr/sup 90/ thermoelectric generator, the relay panel, the batteries, and the installation of the system in a boattype buoy are described. In addition to delivering the power supply, many tests were required for the SNAP-7D system to demonstrate its conformance to the contract statement of work. The electrical tests of the generator and of the system, the shock and vibration tests, and themore » tests at the environmental temperature extremes are discussed. (auth) Quantitative studies were made of the angular distribution of elastic and inelastic scattering of 25-kev electrons on noble gases, and the results were compared with scattering theory in the Born approximation. Results are presented in tables and graphs. (M.C.G.)« less

Survival rates of invasive breast cancer among ethnic Chinese women born in East Asia and the United States.

PubMed

Chuang, Shu-Chun; Chen, Wenping; Hashibe, Mia; Li, Gang; Zhang, Zuo-Feng

2006-01-01

Few studies have compared the breast cancer survival rates of US born ethnic Chinese women and the survival rates of Chinese immigrants. The main purpose of this study is to explore the difference of breast cancer survival rates between the two populations and compare the survival rates to those of Caucasians born in the US. Between 1973 and 2002, 365,215 women who had been diagnosed with primary invasive breast cancer (ICD-O-2 C500:C509) were recorded in the Surveillance, Epidemiology, and End Results (SEER) registries. Of the 316,881 breast cancer patients who were white, 180,835 (57%) were born in the United States, 20,983 (7%) were born elsewhere, and 115,063 (36%) had unknown birthplaces. Among the 3,634 breast cancer patients who were ethnically Chinese, 952 (26%) patients were born in the US, 1,356 (37%) were born in East Asia, 146 (4%) were born elsewhere, and 1,180 (33%) had unknown birthplaces. We compared the survival rates and estimated the risk ratios (RRs) by the Kaplan-Meier estimates and the Cox proportional hazards models. A lower 5-year overall survival rate of breast cancer was observed among Chinese women born in East Asia (0.74, 95% CI=0.72-0.77) than those born in the U.S. (0.79, 95% CI=0.76-0.81), with an adjusted hazards ratio of 1.22 (95% CI=1.06-1.40). The 5-year survival rates for SEER stage were higher among Chinese women born in the U.S. (localized: 0.90, 95% CI=0.87-0.93; regional: 0.71, 95% CI=66-0.77; distant: 0.16, 95% CI=0.06-0.25) than that among Chinese women born in East Asia (localized: 0.86, 95% CI=0.83-0.89; regional: 0.68, 95% CI=0.63-0.73; distant: 0.16, 95% CI=0.07-0.25). Higher 5-year survival rates among Chinese women born in the U.S. in comparison to Chinese women born in East Asia were also observed in different calendar years (1973-1980, 1981-1990, 1991-2002), in surgery and radiation therapy. Our analysis showed that among the Chinese breast cancer patients, women born in East Asia had lower 5-year survival rates than women born in the United States. SEER stage, grade, and tumor size appear to be important prognostic factors. The poor 5-year survival rates among Chinese women born in East Asia indicate potential problems of accessing medical facilities for early detection, diagnosis and treatment because of potential language and culture barriers, lower education level, as well as stress of the first generation of migrant Chinese women in the United States.

Climate change and Ixodes tick-borne diseases of humans

PubMed Central

Ostfeld, Richard S.; Brunner, Jesse L.

2015-01-01

The evidence that climate warming is changing the distribution of Ixodes ticks and the pathogens they transmit is reviewed and evaluated. The primary approaches are either phenomenological, which typically assume that climate alone limits current and future distributions, or mechanistic, asking which tick-demographic parameters are affected by specific abiotic conditions. Both approaches have promise but are severely limited when applied separately. For instance, phenomenological approaches (e.g. climate envelope models) often select abiotic variables arbitrarily and produce results that can be hard to interpret biologically. On the other hand, although laboratory studies demonstrate strict temperature and humidity thresholds for tick survival, these limits rarely apply to field situations. Similarly, no studies address the influence of abiotic conditions on more than a few life stages, transitions or demographic processes, preventing comprehensive assessments. Nevertheless, despite their divergent approaches, both mechanistic and phenomenological models suggest dramatic range expansions of Ixodes ticks and tick-borne disease as the climate warms. The predicted distributions, however, vary strongly with the models' assumptions, which are rarely tested against reasonable alternatives. These inconsistencies, limited data about key tick-demographic and climatic processes and only limited incorporation of non-climatic processes have weakened the application of this rich area of research to public health policy or actions. We urge further investigation of the influence of climate on vertebrate hosts and tick-borne pathogen dynamics. In addition, testing model assumptions and mechanisms in a range of natural contexts and comparing their relative importance as competing models in a rigorous statistical framework will significantly advance our understanding of how climate change will alter the distribution, dynamics and risk of tick-borne disease. PMID:25688022

Inactivation of a model coliphage virus in water by iodine

NASA Technical Reports Server (NTRS)

Brion, Gail M.; Silverstein, Joann

1992-01-01

Until now, NASA's space water reuse research program has not considered the transport of water-borne infectious enteric viruses; however, viral diseases probably are a signifficant concern in long-duration space missions. To simplify monitoring and prediction of pathogen distribution, model indicator strains historically have been used. In this research, the male specific RNA coliphage MS-2 is used as a model of enteric viruses due to their similar size and biochemical composition. Inactivation of some water-borne enteric viruses by iodine has previously been characterized. In this paper, iodine inactivation of the model coliphage MS-2 in buffered water is compared with earlier bench-scale disinfection survival data and with survival in iodinated simulated shower water used in a test water recycling system.

Bayesian data assimilation provides rapid decision support for vector-borne diseases

PubMed Central

Jewell, Chris P.; Brown, Richard G.

2015-01-01

Predicting the spread of vector-borne diseases in response to incursions requires knowledge of both host and vector demographics in advance of an outbreak. Although host population data are typically available, for novel disease introductions there is a high chance of the pathogen using a vector for which data are unavailable. This presents a barrier to estimating the parameters of dynamical models representing host–vector–pathogen interaction, and hence limits their ability to provide quantitative risk forecasts. The Theileria orientalis (Ikeda) outbreak in New Zealand cattle demonstrates this problem: even though the vector has received extensive laboratory study, a high degree of uncertainty persists over its national demographic distribution. Addressing this, we develop a Bayesian data assimilation approach whereby indirect observations of vector activity inform a seasonal spatio-temporal risk surface within a stochastic epidemic model. We provide quantitative predictions for the future spread of the epidemic, quantifying uncertainty in the model parameters, case infection times and the disease status of undetected infections. Importantly, we demonstrate how our model learns sequentially as the epidemic unfolds and provide evidence for changing epidemic dynamics through time. Our approach therefore provides a significant advance in rapid decision support for novel vector-borne disease outbreaks. PMID:26136225

Uncertainty associated with convective wet removal of entrained aerosols in a global climate model

NASA Astrophysics Data System (ADS)

Croft, B.; Pierce, J. R.; Martin, R. V.; Hoose, C.; Lohmann, U.

2012-11-01

The uncertainties associated with the wet removal of aerosols entrained above convective cloud bases are investigated in a global aerosol-climate model (ECHAM5-HAM) under a set of limiting assumptions for the wet removal of the entrained aerosols. The limiting assumptions for the wet removal of entrained aerosols are negligible scavenging and vigorous scavenging (either through activation, with size-dependent impaction scavenging, or with the prescribed fractions of the standard model). To facilitate this process-based study, an explicit representation of cloud-droplet-borne and ice-crystal-borne aerosol mass and number, for the purpose of wet removal, is introduced into the ECHAM5-HAM model. This replaces and is compared with the prescribed cloud-droplet-borne and ice-crystal-borne aerosol fraction scavenging scheme of the standard model. A 20% to 35% uncertainty in simulated global, annual mean aerosol mass burdens and optical depth (AOD) is attributed to different assumptions for the wet removal of aerosols entrained above convective cloud bases. Assumptions about the removal of aerosols entrained above convective cloud bases control modeled upper tropospheric aerosol concentrations by as much as one order of magnitude. Simulated aerosols entrained above convective cloud bases contribute 20% to 50% of modeled global, annual mean aerosol mass convective wet deposition (about 5% to 10% of the total dry and wet deposition), depending on the aerosol species, when including wet scavenging of those entrained aerosols (either by activation, size-dependent impaction, or with the prescribed fraction scheme). Among the simulations, the prescribed fraction and size-dependent impaction schemes yield the largest global, annual mean aerosol mass convective wet deposition (by about two-fold). However, the prescribed fraction scheme has more vigorous convective mixed-phase wet removal (by two to five-fold relative to the size-dependent impaction scheme) since nearly all entrained accumulation and coarse mode aerosols are assumed to be cloud-droplet borne or ice-crystal borne, and evaporation due to the Bergeron-Findeisen process is neglected. The simulated convective wet scavenging of entrained accumulation and coarse mode aerosols has feedbacks on new particle formation and the number of Aitken mode aerosols, which control stratiform and convective cloud droplet number concentrations and yield precipitation changes in the ECHAM5-HAM model. However, the geographic distribution of aerosol annual mean convective wet deposition change in the model is driven by changes to the assumptions regarding the scavenging of aerosols entrained above cloud bases rather than by precipitation changes, except for sea salt deposition in the tropics. Uncertainty in the seasonal, regional cycles of AOD due to assumptions about entrained aerosol wet scavenging is similar in magnitude to the estimated error in the AOD retrievals. The uncertainty in aerosol concentrations, burdens, and AOD attributed to different assumptions for the wet scavenging of aerosols entrained above convective cloud bases in a global model motivates the ongoing need to better understand and model the activation and impaction processes that aerosols undergo after entrainment into convective updrafts.

Impact of climate change upon vector born diseases in Europe and Africa using ENSEMBLES Regional Climate Models

NASA Astrophysics Data System (ADS)

Caminade, Cyril; Morse, Andy

2010-05-01

Climate variability is an important component in determining the incidence of a number of diseases with significant human/animal health and socioeconomic impacts. The most important diseases affecting health are vector-borne, such as malaria, Rift Valley Fever and including those that are tick borne, with over 3 billion of the world population at risk. Malaria alone is responsible for at least one million deaths annually, with 80% of malaria deaths occurring in sub-Saharan Africa. The climate has a large impact upon the incidence of vector-borne diseases; directly via the development rates and survival of both the pathogen and the vector, and indirectly through changes in the environmental conditions. A large ensemble of regional climate model simulations has been produced within the ENSEMBLES project framework for both the European and African continent. This work will present recent progress in human and animal disease modelling, based on high resolution climate observations and regional climate simulations. Preliminary results will be given as an illustration, including the impact of climate change upon bluetongue (disease affecting the cattle) over Europe and upon malaria and Rift Valley Fever over Africa. Malaria scenarios based on RCM ensemble simulations have been produced for West Africa. These simulations have been carried out using the Liverpool Malaria Model. Future projections highlight that the malaria incidence decreases at the northern edge of the Sahel and that the epidemic belt is shifted southward in autumn. This could lead to significant public health problems in the future as the demography is expected to dramatically rise over Africa for the 21st century.

Space-Borne Laser Altimeter Geolocation Error Analysis

NASA Astrophysics Data System (ADS)

Wang, Y.; Fang, J.; Ai, Y.

2018-05-01

This paper reviews the development of space-borne laser altimetry technology over the past 40 years. Taking the ICESAT satellite as an example, a rigorous space-borne laser altimeter geolocation model is studied, and an error propagation equation is derived. The influence of the main error sources, such as the platform positioning error, attitude measurement error, pointing angle measurement error and range measurement error, on the geolocation accuracy of the laser spot are analysed by simulated experiments. The reasons for the different influences on geolocation accuracy in different directions are discussed, and to satisfy the accuracy of the laser control point, a design index for each error source is put forward.

Acculturation and psychosocial stress show differential relationships to insulin resistance (HOMA) and body fat distribution in two groups of blacks living in the US Virgin Islands.

PubMed Central

Tull, Eugene S.; Thurland, Anne; LaPorte, Ronald E.; Chambers, Earle C.

2003-01-01

The objective of this study was to determine whether acculturation and psychosocial stress exert differential effects on body fat distribution and insulin resistance among native-born African Americans and African-Caribbean immigrants living in the US Virgin Islands (USVI). Data collected from a non-diabetic sample of 183 USVI-born African Americans and 296 African-Caribbean immigrants age > 20 on the island of St. Croix, USVI were studied. Information on demographic characteristics, acculturation and psychosocial stress was collected by questionnaire. Anthropometric measurements were taken, and serum glucose and insulin were measured from fasting blood samples. Insulin resistance was estimated by the homeostasis model assessment (HOMA) method. The results showed that in multivariate regression analyses, controlling for age, education, gender, BMI, waist circumference, family history of diabetes, smoking and alcohol consumption, acculturation was independently related to logarithm of HOMA (InHOMA) scores among USVI-born African Americans, but not among African-Caribbean immigrants. In contrast, among USVI-born African Americans psychosocial stress was not significantly related to InHOMA, while among African-Caribbean immigrants psychosocial stress was independently related to InHOMA in models that included BMI, but not in those which included waist circumference. This study suggests that acculturation and psychosocial stress may have a differential effect on body fat distribution and insulin resistance among native-born and immigrant blacks living in the US Virgin Islands. PMID:12911254

Dynamics of Zika virus outbreaks: an overview of mathematical modeling approaches.

PubMed

Wiratsudakul, Anuwat; Suparit, Parinya; Modchang, Charin

2018-01-01

The Zika virus was first discovered in 1947. It was neglected until a major outbreak occurred on Yap Island, Micronesia, in 2007. Teratogenic effects resulting in microcephaly in newborn infants is the greatest public health threat. In 2016, the Zika virus epidemic was declared as a Public Health Emergency of International Concern (PHEIC). Consequently, mathematical models were constructed to explicitly elucidate related transmission dynamics. In this review article, two steps of journal article searching were performed. First, we attempted to identify mathematical models previously applied to the study of vector-borne diseases using the search terms "dynamics," "mathematical model," "modeling," and "vector-borne" together with the names of vector-borne diseases including chikungunya, dengue, malaria, West Nile, and Zika. Then the identified types of model were further investigated. Second, we narrowed down our survey to focus on only Zika virus research. The terms we searched for were "compartmental," "spatial," "metapopulation," "network," "individual-based," "agent-based" AND "Zika." All relevant studies were included regardless of the year of publication. We have collected research articles that were published before August 2017 based on our search criteria. In this publication survey, we explored the Google Scholar and PubMed databases. We found five basic model architectures previously applied to vector-borne virus studies, particularly in Zika virus simulations. These include compartmental, spatial, metapopulation, network, and individual-based models. We found that Zika models carried out for early epidemics were mostly fit into compartmental structures and were less complicated compared to the more recent ones. Simple models are still commonly used for the timely assessment of epidemics. Nevertheless, due to the availability of large-scale real-world data and computational power, recently there has been growing interest in more complex modeling frameworks. Mathematical models are employed to explore and predict how an infectious disease spreads in the real world, evaluate the disease importation risk, and assess the effectiveness of intervention strategies. As the trends in modeling of infectious diseases have been shifting towards data-driven approaches, simple and complex models should be exploited differently. Simple models can be produced in a timely fashion to provide an estimation of the possible impacts. In contrast, complex models integrating real-world data require more time to develop but are far more realistic. The preparation of complicated modeling frameworks prior to the outbreaks is recommended, including the case of future Zika epidemic preparation.

Variation in Birth Outcomes by Mother’s Country of Birth Among Non-Hispanic Black Women in the United States

PubMed Central

Vang, Zoua; Culhane, Jennifer F.

2014-01-01

Rates of prematurity (PTB) and small-for-gestational age (SGA) were compared between US-born and foreign-born non-Hispanic black women. Comparisons were also made between Sub-Saharan African-born and Caribbean-born black women and by maternal country of birth within the two regions. Comparisons were adjusted for sociodemographic, health behavioral and medical risk factors available on the birth record. Birth record data (2008) from all states (n = 27) where mother’s country of birth was recorded were used. These data comprised 58 % of all singleton births to non-Hispanic black women in that year. Pearson Chi square and logistic regression were used to investigate variation in the rates of PTB and SGA by maternal nativity. Foreign-born non-Hispanic black women had significantly lower rates of PTB (OR 0.727; CI 0. 726, 0.727) and SGA (OR 0.742; CI 0.739–0.745) compared to US-born non-Hispanic black women in a fully adjusted model. Sub-Saharan African-born black women compared to Caribbean-born black women had significantly lower rates of PTB and SGA. Within each region, the rates of PTB and SGA varied by mother’s country of birth. These differences could not be explained by adjustment for known risk factors obtained from vital records. Considerable heterogeneity in rates of PTB and SGA among non-Hispanic black women in the US by maternal nativity was documented and remained unexplained after adjustment for known risk factors. PMID:24756226

Inflows of foreign-born physicians and their access to employment and work experiences in health care in Finland: qualitative and quantitative study

PubMed Central

2014-01-01

Background In many developed countries, including Finland, health care authorities customarily consider the international mobility of physicians as a means for addressing the shortage of general practitioners (GPs). This study i) examined, based on register information, the numbers of foreign-born physicians migrating to Finland and their employment sector, ii) examined, based on qualitative interviews, the foreign-born GPs’ experiences of accessing employment and work in primary care in Finland, and iii) compared experiences based on a survey of the psychosocial work environment among foreign-born physicians working in different health sectors (primary care, hospitals and private sectors). Methods Three different data sets were used: registers, theme interviews among foreign-born GPs (n = 12), and a survey for all (n = 1,292; response rate 42%) foreign-born physicians living in Finland. Methods used in the analyses were qualitative content analysis, analysis of covariance, and logistic regression analysis. Results The number of foreign-born physicians has increased dramatically in Finland since the year 2000. In 2000, a total of 980 foreign-born physicians held a Finnish licence and lived in Finland, accounting for less than 4% of the total number of practising physicians. In 2009, their proportion of all physicians was 8%, and a total of 1,750 foreign-born practising physicians held a Finnish licence and lived in Finland. Non-EU/EEA physicians experienced the difficult licensing process as the main obstacle to accessing work as a physician. Most licensed foreign-born physicians worked in specialist care. Half of the foreign-born GPs could be classified as having an ‘active’ job profile (high job demands and high levels of job control combined) according to Karasek’s demand-control model. In qualitative interviews, work in the Finnish primary health centres was described as multifaceted and challenging, but also stressful. Conclusions Primary care may not be able in the long run to attract a sufficient number of foreign-born GPs to alleviate Finland’s GP shortage, although speeding up the licensing process may bring in more foreign-born physicians to work, at least temporarily, in primary care. For physicians to be retained as active GPs there needs to be improvement in the psychosocial work environment within primary care. PMID:25103861

Inflows of foreign-born physicians and their access to employment and work experiences in health care in Finland: qualitative and quantitative study.

PubMed

Kuusio, Hannamaria; Lämsä, Riikka; Aalto, Anna-Mari; Manderbacka, Kristiina; Keskimäki, Ilmo; Elovainio, Marko

2014-08-07

In many developed countries, including Finland, health care authorities customarily consider the international mobility of physicians as a means for addressing the shortage of general practitioners (GPs). This study i) examined, based on register information, the numbers of foreign-born physicians migrating to Finland and their employment sector, ii) examined, based on qualitative interviews, the foreign-born GPs' experiences of accessing employment and work in primary care in Finland, and iii) compared experiences based on a survey of the psychosocial work environment among foreign-born physicians working in different health sectors (primary care, hospitals and private sectors). Three different data sets were used: registers, theme interviews among foreign-born GPs (n = 12), and a survey for all (n = 1,292; response rate 42%) foreign-born physicians living in Finland. Methods used in the analyses were qualitative content analysis, analysis of covariance, and logistic regression analysis. The number of foreign-born physicians has increased dramatically in Finland since the year 2000. In 2000, a total of 980 foreign-born physicians held a Finnish licence and lived in Finland, accounting for less than 4% of the total number of practising physicians. In 2009, their proportion of all physicians was 8%, and a total of 1,750 foreign-born practising physicians held a Finnish licence and lived in Finland. Non-EU/EEA physicians experienced the difficult licensing process as the main obstacle to accessing work as a physician. Most licensed foreign-born physicians worked in specialist care. Half of the foreign-born GPs could be classified as having an 'active' job profile (high job demands and high levels of job control combined) according to Karasek's demand-control model. In qualitative interviews, work in the Finnish primary health centres was described as multifaceted and challenging, but also stressful. Primary care may not be able in the long run to attract a sufficient number of foreign-born GPs to alleviate Finland's GP shortage, although speeding up the licensing process may bring in more foreign-born physicians to work, at least temporarily, in primary care. For physicians to be retained as active GPs there needs to be improvement in the psychosocial work environment within primary care.

Maternal pre-pregnancy BMI and offspring body composition in young adulthood: the modifying role of offspring sex and birth order.

PubMed

Chaparro, M Pia; Koupil, Ilona; Byberg, Liisa

2017-12-01

To investigate if the association between maternal pre-pregnancy BMI and offspring's body composition in late adolescence and young adulthood varies by offspring birth order and sex. Family cohort study, with data from registers, questionnaires and physical examinations. The main outcome under study was offspring body composition (percentage fat mass (%FM), percentage lean mass (%LM)) measured by dual-energy X-ray absorptiometry. Uppsala, Sweden. Two hundred and twenty-six siblings (first-born v. second-born; average age 19 and 21 years) and their mothers. In multivariable linear regression models, maternal pre-pregnancy BMI was positively associated with daughter's %FM, with stronger estimates for first-born (β=0·97, 95 % CI 0·14, 1·80) v. second-born daughters (β=0·64, 95 % CI 0·08, 1·20). Mother's BMI before her first pregnancy was associated with her second-born daughter's body composition (β=1·05, 95 % CI 0·31, 1·79 (%FM)) Similar results albeit in the opposite direction were observed for %LM. No significant associations were found between pre-pregnancy BMI and %FM (β=0·59, 95 % CI-0·27, 1·44 first-born; β=-0·13, 95 % CI-0·77, 0·52 second-born) or %LM (β=-0·54, 95 % CI-1·37, 0·28 first-born; β=0·11, 95 % CI-0·52, 0·74 second-born) for sons. A higher pre-pregnancy BMI was associated with higher offspring %FM and lower offspring %LM in late adolescence and young adulthood, with stronger associations for first-born daughters. Preventing obesity at the start of women's reproductive life might reduce the risk of obesity in her offspring, particularly for daughters.

Analysis of the sensitivity properties of a model of vector-borne bubonic plague.

PubMed

Buzby, Megan; Neckels, David; Antolin, Michael F; Estep, Donald

2008-09-06

Model sensitivity is a key to evaluation of mathematical models in ecology and evolution, especially in complex models with numerous parameters. In this paper, we use some recently developed methods for sensitivity analysis to study the parameter sensitivity of a model of vector-borne bubonic plague in a rodent population proposed by Keeling & Gilligan. The new sensitivity tools are based on a variational analysis involving the adjoint equation. The new approach provides a relatively inexpensive way to obtain derivative information about model output with respect to parameters. We use this approach to determine the sensitivity of a quantity of interest (the force of infection from rats and their fleas to humans) to various model parameters, determine a region over which linearization at a specific parameter reference point is valid, develop a global picture of the output surface, and search for maxima and minima in a given region in the parameter space.

Stratospheric free chlorine measured by balloon-borne in situ resonance fluorescence

NASA Technical Reports Server (NTRS)

Anderson, J. G.; Grassl, H. J.; Shetter, R. E.; Margitan, J. J.

1980-01-01

Eight balloon-borne in situ measurements of ClO in the stratosphere are analyzed and are compared with recent model calculations. While the use of in situ stratospheric studies of free radicals to test models by comparing observed and predicted concentration profiles is essential for a prognosis of changes in stratospheric ozone, resulting from future changes in stratospheric ozone, such studies provide only limited insight into the nature of stratospheric photochemistry, because natural variability and the large number of fast reactions which compete in the coupling among the key radicals frustrate a detailed comparison between a mean distribution provided by the models and an instantaneous distribution provided by a single observation.

Research on precise modeling of buildings based on multi-source data fusion of air to ground

NASA Astrophysics Data System (ADS)

Li, Yongqiang; Niu, Lubiao; Yang, Shasha; Li, Lixue; Zhang, Xitong

2016-03-01

Aims at the accuracy problem of precise modeling of buildings, a test research was conducted based on multi-source data for buildings of the same test area , including top data of air-borne LiDAR, aerial orthophotos, and façade data of vehicle-borne LiDAR. After accurately extracted the top and bottom outlines of building clusters, a series of qualitative and quantitative analysis was carried out for the 2D interval between outlines. Research results provide a reliable accuracy support for precise modeling of buildings of air ground multi-source data fusion, on the same time, discussed some solution for key technical problems.

2-D Fused Image Reconstruction approach for Microwave Tomography: a theoretical assessment using FDTD Model.

PubMed

Bindu, G; Semenov, S

2013-01-01

This paper describes an efficient two-dimensional fused image reconstruction approach for Microwave Tomography (MWT). Finite Difference Time Domain (FDTD) models were created for a viable MWT experimental system having the transceivers modelled using thin wire approximation with resistive voltage sources. Born Iterative and Distorted Born Iterative methods have been employed for image reconstruction with the extremity imaging being done using a differential imaging technique. The forward solver in the imaging algorithm employs the FDTD method of solving the time domain Maxwell's equations with the regularisation parameter computed using a stochastic approach. The algorithm is tested with 10% noise inclusion and successful image reconstruction has been shown implying its robustness.

Mitigating Insider Threat Using Human Behavior Influence Models

DTIC Science & Technology

2006-06-01

such as misdemeanors, lawsuits, divorce proceedings, or child custody suits. Major Legal Activity occurs when an employee experiences major legal...1994 Child born Change in Family (positive) 2002 Family trouble Change in Family (negative) 1995 Pay Raise Change in work environment (positive...and lawsuit Legal Activity (minor) 2003 Family trouble Change in Family (negative) 1997 Child born Change in Family (positive) 2003 Health Problem

Performance of a postnatal metabolic gestational age algorithm: a retrospective validation study among ethnic subgroups in Canada

PubMed Central

Hawken, Steven; Ducharme, Robin; Murphy, Malia S Q; Atkinson, Katherine M; Potter, Beth K; Chakraborty, Pranesh; Wilson, Kumanan

2017-01-01

Objectives Biological modelling of routinely collected newborn screening data has emerged as a novel method for deriving postnatal gestational age estimates. Validation of published models has previously been limited to cohorts largely consisting of infants of white Caucasian ethnicity. In this study, we sought to determine the validity of a published gestational age estimation algorithm among recent immigrants to Canada, where maternal landed immigrant status was used as a surrogate measure of infant ethnicity. Design We conducted a retrospective validation study in infants born in Ontario between April 2009 and September 2011. Setting Provincial data from Ontario, Canada were obtained from the Institute for Clinical Evaluative Sciences. Participants The dataset included 230 034 infants born to non-landed immigrants and 70 098 infants born to immigrant mothers. The five most common countries of maternal origin were India (n=10 038), China (n=7468), Pakistan (n=5824), The Philippines (n=5441) and Vietnam (n=1408). Maternal country of origin was obtained from Citizenship and Immigration Canada’s Landed Immigrant Database. Primary and secondary outcome measures Performance of a postnatal gestational age algorithm was evaluated across non-immigrant and immigrant populations. Results Root mean squared error (RMSE) of 1.05 weeks was observed for infants born to non-immigrant mothers, whereas RMSE ranged from 0.98 to 1.15 weeks among infants born to immigrant mothers. Area under the receiver operating characteristic curve for distinguishing term versus preterm infants (≥37 vs <37 weeks gestational age or >34 vs ≤34 weeks gestational age) was 0.958 and 0.986, respectively, in the non-immigrant subgroup and ranged from 0.927 to 0.964 and 0.966 to 0.99 in the immigrant subgroups. Conclusions Algorithms for postnatal determination of gestational age may be further refined by development and validation of region or ethnicity-specific models. However, our results provide reassurance that an algorithm developed from Ontario-born infant cohorts performs well across a range of ethnicities and maternal countries of origin without modification. PMID:28871012

Performance of a postnatal metabolic gestational age algorithm: a retrospective validation study among ethnic subgroups in Canada.

PubMed

Hawken, Steven; Ducharme, Robin; Murphy, Malia S Q; Atkinson, Katherine M; Potter, Beth K; Chakraborty, Pranesh; Wilson, Kumanan

2017-09-03

Biological modelling of routinely collected newborn screening data has emerged as a novel method for deriving postnatal gestational age estimates. Validation of published models has previously been limited to cohorts largely consisting of infants of white Caucasian ethnicity. In this study, we sought to determine the validity of a published gestational age estimation algorithm among recent immigrants to Canada, where maternal landed immigrant status was used as a surrogate measure of infant ethnicity. We conducted a retrospective validation study in infants born in Ontario between April 2009 and September 2011. Provincial data from Ontario, Canada were obtained from the Institute for Clinical Evaluative Sciences. The dataset included 230 034 infants born to non-landed immigrants and 70 098 infants born to immigrant mothers. The five most common countries of maternal origin were India (n=10 038), China (n=7468), Pakistan (n=5824), The Philippines (n=5441) and Vietnam (n=1408). Maternal country of origin was obtained from Citizenship and Immigration Canada's Landed Immigrant Database. Performance of a postnatal gestational age algorithm was evaluated across non-immigrant and immigrant populations. Root mean squared error (RMSE) of 1.05 weeks was observed for infants born to non-immigrant mothers, whereas RMSE ranged from 0.98 to 1.15 weeks among infants born to immigrant mothers. Area under the receiver operating characteristic curve for distinguishing term versus preterm infants (≥37 vs <37 weeks gestational age or >34 vs ≤34 weeks gestational age) was 0.958 and 0.986, respectively, in the non-immigrant subgroup and ranged from 0.927 to 0.964 and 0.966 to 0.99 in the immigrant subgroups. Algorithms for postnatal determination of gestational age may be further refined by development and validation of region or ethnicity-specific models. However, our results provide reassurance that an algorithm developed from Ontario-born infant cohorts performs well across a range of ethnicities and maternal countries of origin without modification. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Regulation of the Immune Response to α-Gal and Vector-borne Diseases.

PubMed

Cabezas-Cruz, Alejandro; Mateos-Hernández, Lourdes; Pérez-Cruz, Magdiel; Valdés, James J; Mera, Isabel G Fernández de; Villar, Margarita; de la Fuente, José

2015-10-01

Vector-borne diseases (VBD) challenge our understanding of emerging diseases. Recently, arthropod vectors have been involved in emerging anaphylactic diseases. In particular, the immunoglobulin E (IgE) antibody response to the carbohydrate Galα1-3Galβ1-(3)4GlcNAc-R (α-gal) following a tick bite was associated with allergies to red meat, cetuximab, and gelatin. By contrast, an anti-α-gal IgM antibody response was shown to protect against mosquito-borne malaria. Herein, we highlight the interplay between the gut microbiota, vectors, transmitted pathogens, and the regulation of the immune response as a model to understand the protective or allergic effect of α-gal. Establishing the source of α-gal in arthropod vectors and the immune response to vector bites and transmitted pathogens will be essential for diagnosing, treating, and ultimately preventing these emerging anaphylactic and other vector-borne diseases. Copyright © 2015 Elsevier Ltd. All rights reserved.

Change-point analysis data of neonatal diffusion tensor MRI in preterm and term-born infants.

PubMed

Wu, Dan; Chang, Linda; Akazawa, Kentaro; Oishi, Kumiko; Skranes, Jon; Ernst, Thomas; Oishi, Kenichi

2017-06-01

The data presented in this article are related to the research article entitled "Mapping the Critical Gestational Age at Birth that Alters Brain Development in Preterm-born Infants using Multi-Modal MRI" (Wu et al., 2017) [1]. Brain immaturity at birth poses critical neurological risks in the preterm-born infants. We used a novel change-point model to analyze the critical gestational age at birth (GAB) that could affect postnatal development, based on diffusion tensor MRI (DTI) acquired from 43 preterm and 43 term-born infants in 126 brain regions. In the corresponding research article, we presented change-point analysis of fractional anisotropy (FA) and mean diffusivities (MD) measurements in these infants. In this article, we offered the relative changes of axonal and radial diffusivities (AD and RD) in relation to the change of FA and FA-based change-points, and we also provided the AD- and RD-based change-point results.

Electric bicycle cost calculation models and analysis based on the social perspective in China.

PubMed

Yan, Xuetong; He, Jie; King, Mark; Hang, Wen; Zhou, Bojian

2018-05-10

Electric bicycles (EBs) are increasingly popular around the world. In April 2014, EB ownership in China reached 181 million. While some aspects of the impact of EBs have been studied, most of the literature analyzing the cost of EBs has been conducted from the buyer's point of view and the perspective of social cost has not been covered, which is therefore the focus of this paper. From the consumer's point of view, only the costs paid from purchase until retirement are included in the cost of EBs, i.e., the EB acquisition cost, battery replacement cost, charging cost, and repair and maintenance cost are included. Considered from the perspective of the social cost (including impact on the environment), costs that are not paid directly by consumers should also be included in the cost of EBs, i.e., the lead-acid battery scrap processing cost, the cost of pollution caused by wastewater, and the traffic-related costs. Data are obtained from secondary sources and surveys, and calculations demonstrate that in the life cycle of an EB, the consumer cost is 6386.2 CNY, the social cost is 10,771.2 CNY, and the ratio of consumer to social cost is 1:1.69. By comparison, the ratio for motor vehicles is 1:1.06, so that the share of the life cycle cost of EBs that is not borne by the consumer is much higher than that for motor vehicles, which needs to be addressed.

Dengue: recent past and future threats

PubMed Central

Rogers, David J.

2015-01-01

This article explores four key questions about statistical models developed to describe the recent past and future of vector-borne diseases, with special emphasis on dengue: (1) How many variables should be used to make predictions about the future of vector-borne diseases?(2) Is the spatial resolution of a climate dataset an important determinant of model accuracy?(3) Does inclusion of the future distributions of vectors affect predictions of the futures of the diseases they transmit?(4) Which are the key predictor variables involved in determining the distributions of vector-borne diseases in the present and future?Examples are given of dengue models using one, five or 10 meteorological variables and at spatial resolutions of from one-sixth to two degrees. Model accuracy is improved with a greater number of descriptor variables, but is surprisingly unaffected by the spatial resolution of the data. Dengue models with a reduced set of climate variables derived from the HadCM3 global circulation model predictions for the 1980s are improved when risk maps for dengue's two main vectors (Aedes aegypti and Aedes albopictus) are also included as predictor variables; disease and vector models are projected into the future using the global circulation model predictions for the 2020s, 2040s and 2080s. The Garthwaite–Koch corr-max transformation is presented as a novel way of showing the relative contribution of each of the input predictor variables to the map predictions. PMID:25688021

Birth order and risk of childhood cancer in the Danish birth cohort of 1973-2010.

PubMed

Schüz, Joachim; Luta, George; Erdmann, Friederike; Ferro, Gilles; Bautz, Andrea; Simony, Sofie Bay; Dalton, Susanne Oksbjerg; Lightfoot, Tracy; Winther, Jeanette Falck

2015-11-01

Many studies have investigated the possible association between birth order and risk of childhood cancer, although the evidence to date has been inconsistent. Birth order has been used as a marker for various in utero or childhood exposures and is relatively straightforward to assess. Data were obtained on all children born in Denmark between 1973 and 2010, involving almost 2.5 million births and about 5,700 newly diagnosed childhood cancers before the age of 20 years. Data were analyzed using Poisson regression models. We failed to observe associations between birth order and risk of any childhood cancer subtype, including acute lymphoblastic leukemia; all rate ratios were close to one. Further analyses stratified by birth cohort (those born between 1973 and 1990, and those born between 1991 and 2010) also failed to show any associations. Considering stillbirths and/or controlling for birth weight and parental age in the analyses had no effect on the results. Analyses by years of birth (those born between 1973 and 1990, and those born between 1991 and 2010) did not show any changes in the overall pattern of no association. In this large cohort of all children born in Denmark over an almost 40-year period, we did not observe an association between birth order and the risk of childhood cancer.

[Differential impact of social capital on mental health in the native-born and immigrant populations living in Catalonia (Spain)].

PubMed

Stoyanova, Alexandrina; Díaz-Serrano, Luis

2009-12-01

This study attempts to create a bridge between the literature on immigration and on social capital and health. The objectives were two-fold: firstly, to provide new empirical evidence on the association between social capital and health, using data from Catalonia for the first time and, secondly, to explore the possible existence of a differential impact of social capital on health between native-born residents and immigrants. We also distinguished between individual and community-level social capital. We used the 2006 Catalan Health Survey (ESCA 2006). To assess the relationship between social capital and mental health, we used multilevel models, estimated separately for native-born and immigrant residents. The results revealed a positive link between social capital and good mental health in Catalonia. However, this effect was stronger for individual than for community-level social capital. The results did not support the hypothesis of a differential impact between immigrants and native-born Catalans, but did indicate differences with respect to Spaniards born outside Catalonia. Geographic heterogeneity in the effect of individual social capital on mental health in both immigrants and native-born residents was also detected. We believe that enhancing social capital could potentially be an effective policy tool to achieve objectives related to health status improvement.

Topics in electron capture by fast ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsin, S.H.

1987-01-01

The post-collision interaction (PCI) model was applied, together with the eikonal approximation, to study the (n = 2,3) capture cross sections in p + H(ls) collisions. The results indeed improve the previous eikonal calculations for l = 0 cases, and agree quite well with present experimental data. Calculations using the strong-potential Born (SPB) approximation, with the Sil and McGuire technique, for capture into the np, nd levels are also presented. While these cross sections are smaller than cross sections for capture into the ns levels at high velocities, nevertheless the Thomas peak is clearly evident in both the absolute valuemore » m = 2, absolute value m = 1 and m = 0 magnetic substates in p + H(ls) collisions. Also calculated were corrections to the SPB using the Distorted-Wave Born formalism of Taulbjerg and Briggs. In the sense of a plane-wave Born expansion, all terms of the third Born approximation and all single switching fourth Born terms are included, but a peaking approximation is needed to reduce the calculation to tractable form. Effects of the higher terms are most visible in the valley between the Thomas peak and the forward peak. The Thomas peak is visible in the correction term, even though it includes no second Born contributions.« less

Internalized racism and mental health among African-Americans, US-born Caribbean Blacks, and foreign-born Caribbean Blacks.

PubMed

Mouzon, Dawne M; McLean, Jamila S

2017-02-01

The tripartite model of racism includes personally mediated racism, institutionalized racism, and the less-oft studied internalized racism. Internalized racism - or negative beliefs about one's racial group - results from cultural racism that is endemic in American society. In this project, we studied whether these negative stereotypes are associated with mental health among African-Americans and Caribbean Blacks. Using secondary data from the National Survey of American Life, we investigated the association between internalized racism and mental health (measured by depressive symptoms and serious psychological distress (SPD)) among these two groups. We also explored whether ethnicity/nativity and mastery moderate the association between internalized racism and mental health among African-Americans and Caribbean Blacks. Internalized racism was positively associated with depressive symptoms and SPD among all Black subgroups. However, internalized racism was a weaker predictor of SPD among foreign-born Caribbean Blacks than US-born Caribbean Blacks and US-born African-Americans. Additionally, higher mastery was protective against distress associated with internalized racism. Internalized racism is an important yet understudied determinant of mental health among Blacks. Future studies should take into account additional heterogeneity within the Black population (e.g. African-born individuals) and other potential protective mechanisms in addition to mastery (e.g. self-esteem and racial identity).

Correction of the near threshold behavior of electron collisional excitation cross-sections in the plane-wave Born approximation

DOE PAGES

Kilcrease, D. P.; Brookes, S.

2013-08-19

The modeling of NLTE plasmas requires the solution of population rate equations to determine the populations of the various atomic levels relevant to a particular problem. The equations require many cross sections for excitation, de-excitation, ionization and recombination. Additionally, a simple and computational fast way to calculate electron collisional excitation cross-sections for ions is by using the plane-wave Born approximation. This is essentially a high-energy approximation and the cross section suffers from the unphysical problem of going to zero near threshold. Various remedies for this problem have been employed with varying degrees of success. We present a correction procedure formore » the Born cross-sections that employs the Elwert–Sommerfeld factor to correct for the use of plane waves instead of Coulomb waves in an attempt to produce a cross-section similar to that from using the more time consuming Coulomb Born approximation. We compare this new approximation with other, often employed correction procedures. Furthermore, we also look at some further modifications to our Born Elwert procedure and its combination with Y.K. Kim's correction of the Coulomb Born approximation for singly charged ions that more accurately approximate convergent close coupling calculations.« less

Recasting the theory of mosquito-borne pathogen transmission dynamics and control.

PubMed

Smith, David L; Perkins, T Alex; Reiner, Robert C; Barker, Christopher M; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M; George, Dylan B; Le Menach, Arnaud; Pulliam, Juliet R C; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A T; Garcia, Andres J; Gatton, Michelle L; Gething, Peter W; Hartley, David M; Johnston, Geoffrey; Klein, Eili Y; Michael, Edwin; Lloyd, Alun L; Pigott, David M; Reisen, William K; Ruktanonchai, Nick; Singh, Brajendra K; Stoller, Jeremy; Tatem, Andrew J; Kitron, Uriel; Godfray, H Charles J; Cohen, Justin M; Hay, Simon I; Scott, Thomas W

2014-04-01

Mosquito-borne diseases pose some of the greatest challenges in public health, especially in tropical and sub-tropical regions of the world. Efforts to control these diseases have been underpinned by a theoretical framework developed for malaria by Ross and Macdonald, including models, metrics for measuring transmission, and theory of control that identifies key vulnerabilities in the transmission cycle. That framework, especially Macdonald's formula for R0 and its entomological derivative, vectorial capacity, are now used to study dynamics and design interventions for many mosquito-borne diseases. A systematic review of 388 models published between 1970 and 2010 found that the vast majority adopted the Ross-Macdonald assumption of homogeneous transmission in a well-mixed population. Studies comparing models and data question these assumptions and point to the capacity to model heterogeneous, focal transmission as the most important but relatively unexplored component in current theory. Fine-scale heterogeneity causes transmission dynamics to be nonlinear, and poses problems for modeling, epidemiology and measurement. Novel mathematical approaches show how heterogeneity arises from the biology and the landscape on which the processes of mosquito biting and pathogen transmission unfold. Emerging theory focuses attention on the ecological and social context for mosquito blood feeding, the movement of both hosts and mosquitoes, and the relevant spatial scales for measuring transmission and for modeling dynamics and control.

Recasting the theory of mosquito-borne pathogen transmission dynamics and control

PubMed Central

Smith, David L.; Perkins, T. Alex; Reiner, Robert C.; Barker, Christopher M.; Niu, Tianchan; Chaves, Luis Fernando; Ellis, Alicia M.; George, Dylan B.; Le Menach, Arnaud; Pulliam, Juliet R. C.; Bisanzio, Donal; Buckee, Caroline; Chiyaka, Christinah; Cummings, Derek A. T.; Garcia, Andres J.; Gatton, Michelle L.; Gething, Peter W.; Hartley, David M.; Johnston, Geoffrey; Klein, Eili Y.; Michael, Edwin; Lloyd, Alun L.; Pigott, David M.; Reisen, William K.; Ruktanonchai, Nick; Singh, Brajendra K.; Stoller, Jeremy; Tatem, Andrew J.; Kitron, Uriel; Godfray, H. Charles J.; Cohen, Justin M.; Hay, Simon I.; Scott, Thomas W.

2014-01-01

Mosquito-borne diseases pose some of the greatest challenges in public health, especially in tropical and sub-tropical regions of the world. Efforts to control these diseases have been underpinned by a theoretical framework developed for malaria by Ross and Macdonald, including models, metrics for measuring transmission, and theory of control that identifies key vulnerabilities in the transmission cycle. That framework, especially Macdonald's formula for R0 and its entomological derivative, vectorial capacity, are now used to study dynamics and design interventions for many mosquito-borne diseases. A systematic review of 388 models published between 1970 and 2010 found that the vast majority adopted the Ross–Macdonald assumption of homogeneous transmission in a well-mixed population. Studies comparing models and data question these assumptions and point to the capacity to model heterogeneous, focal transmission as the most important but relatively unexplored component in current theory. Fine-scale heterogeneity causes transmission dynamics to be nonlinear, and poses problems for modeling, epidemiology and measurement. Novel mathematical approaches show how heterogeneity arises from the biology and the landscape on which the processes of mosquito biting and pathogen transmission unfold. Emerging theory focuses attention on the ecological and social context for mosquito blood feeding, the movement of both hosts and mosquitoes, and the relevant spatial scales for measuring transmission and for modeling dynamics and control. PMID:24591453

Climate change and mosquito-borne disease.

PubMed Central

Reiter, P

2001-01-01

Global atmospheric temperatures are presently in a warming phase that began 250--300 years ago. Speculations on the potential impact of continued warming on human health often focus on mosquito-borne diseases. Elementary models suggest that higher global temperatures will enhance their transmission rates and extend their geographic ranges. However, the histories of three such diseases--malaria, yellow fever, and dengue--reveal that climate has rarely been the principal determinant of their prevalence or range; human activities and their impact on local ecology have generally been much more significant. It is therefore inappropriate to use climate-based models to predict future prevalence. PMID:11250812

[The mathematical modelling of the possible morbidity from epidemic louse-borne typhus under current conditions].

PubMed

Lukin, E P; Mikhaĭlov, V V; Oleĭchik, V L; Solodiankin, A I

1996-01-01

On the basis of their earlier formula for modeling the possible development of the epidemic process of louse-borne exanthematous typhus the authors have calculated the probability of the development of such process for high indices (10 -- 12 % of convalescents with louse contamination rate among them reaching 20 -- 40 %) characterizing this process. The number of sources of this infection (primary patients), as well as the rate of increase and scale of louse contamination of the population, are of prime importance for the prognostication of the development of the epidemic.

Rates of obstetric intervention during birth and selected maternal and perinatal outcomes for low risk women born in Australia compared to those born overseas.

PubMed

Dahlen, Hannah G; Schmied, Virginia; Dennis, Cindy-Lee; Thornton, Charlene

2013-05-01

There are mixed reports in the literature about obstetric intervention and maternal and neonatal outcomes for migrant women born in resource rich countries. The aim of this study was to compare the risk profile, rates of obstetric intervention and selected maternal and perinatal outcomes for low risk women born in Australia compared to those born overseas. A population-based descriptive study was undertaken in NSW of all singleton births recorded in the NSW Midwives Data Collection between 2000-2008 (n=691,738). Risk profile, obstetric intervention rates and selected maternal and perinatal outcomes were examined. Women born in Australia were slightly younger (30 vs 31 years), less likely to be primiparous (41% vs 43%), three times more likely to smoke (18% vs 6%) and more likely to give birth in a private hospital (26% vs 18%) compared to women not born in Australia. Among the seven most common migrant groups to Australia, women born in Lebanon were the youngest, least likely to be primiparous and least likely to give birth in a private hospital. Hypertension was lowest amongst Vietnamese women (3%) and gestational diabetes highest amongst women born in China (14%). The highest caesarean section (31%), instrumental birth rates (16%) and episiotomy rates (32%) were seen in Indian women, along with the highest rates of babies <10th centile (22%) and <3rd centile (8%). Lebanese women had the highest rates of stillbirth (7.2/1000). Similar trends were found in the different migrant groups when only low risk women were included. The results suggest there are significant differences in risk profiles, obstetric intervention rates and maternal and neonatal outcomes between Australian-born and women born overseas and these differences are seen overall and in low risk populations. The finding that Indian women (the leading migrant group to Australia) have the lowest normal birth rate and high rates of low birth weight babies is concerning, and attention needs to be focused on why there are disparities in outcomes and on effective models of care that might improve outcomes for this population.

Prostate Cancer Prognostic Factors Among Asian Patients Born in the US Compared to Those Born Abroad.

PubMed

Xu, Junjun; Goodman, Michael; Jemal, Ahemdin; Fedewa, Stacey A

2015-06-01

US surveillance data indicate that incidence of prostate cancer differs by place of birth among Asian men. However, it is less clear if the prognostic factors for prostate cancer also differ by place of birth. The study included 7,824 Asian prostate cancer patients diagnosed between 2004 and 2009 and reported to the Surveillance Epidemiology and End Results (SEER) program. Logistic regression models were used to evaluate the relation of place of birth (foreign born vs. US born) to three outcomes: prostate specific antigen (PSA) level, Gleason score, and T classification, adjusting for age, marital status, Rural-Urban Continuum Code, and SEER registry. All outcome variables were binary using different cutoffs: ≥ 4, ≥ 10 and ≥ 20 ng/ml for PSA; ≥ 7 and ≥ 8 for Gleason score; and ≥ T2 and ≥ T3 for T classification. Elevated PSA was more common among foreign born Asian men regardless of the cut point used. In the analysis comparing foreign born versus US born patients by ethnic group, the association with PSA was most pronounced at cut point of ≥ 20 ng/ml for Chinese men (OR 1.68, 95% CI 1.02-2.75), and at cut point of ≥ 4 ng/ml for Japanese men (OR 2.73, 95% CI 1.20-6.21). A statistically significant association with Gleason score was only found for Japanese men and only for the cutoff ≥ 7 (OR 1.71, 95% CI 1.12-2.61). There was no difference in clinical T classification between foreign-born and US-born Asian men. Inclusion of cases with missing place of birth or restriction of data to those who underwent radical prostatectomy did not substantially change the results. The data suggest that foreign-born Asian prostate cancer patients may have moderately elevated PSA levels at diagnosis compared with their US born counterparts. For the other prognostic markers, the associations were less consistent and did not form a discernible pattern.

Rates of obstetric intervention during birth and selected maternal and perinatal outcomes for low risk women born in Australia compared to those born overseas

PubMed Central

2013-01-01

Background There are mixed reports in the literature about obstetric intervention and maternal and neonatal outcomes for migrant women born in resource rich countries. The aim of this study was to compare the risk profile, rates of obstetric intervention and selected maternal and perinatal outcomes for low risk women born in Australia compared to those born overseas. Method A population-based descriptive study was undertaken in NSW of all singleton births recorded in the NSW Midwives Data Collection between 2000–2008 (n=691,738). Risk profile, obstetric intervention rates and selected maternal and perinatal outcomes were examined. Results Women born in Australia were slightly younger (30 vs 31 years), less likely to be primiparous (41% vs 43%), three times more likely to smoke (18% vs 6%) and more likely to give birth in a private hospital (26% vs 18%) compared to women not born in Australia. Among the seven most common migrant groups to Australia, women born in Lebanon were the youngest, least likely to be primiparous and least likely to give birth in a private hospital. Hypertension was lowest amongst Vietnamese women (3%) and gestational diabetes highest amongst women born in China (14%). The highest caesarean section (31%), instrumental birth rates (16%) and episiotomy rates (32%) were seen in Indian women, along with the highest rates of babies <10th centile (22%) and <3rd centile (8%). Lebanese women had the highest rates of stillbirth (7.2/1000). Similar trends were found in the different migrant groups when only low risk women were included. Conclusion The results suggest there are significant differences in risk profiles, obstetric intervention rates and maternal and neonatal outcomes between Australian-born and women born overseas and these differences are seen overall and in low risk populations. The finding that Indian women (the leading migrant group to Australia) have the lowest normal birth rate and high rates of low birth weight babies is concerning, and attention needs to be focused on why there are disparities in outcomes and on effective models of care that might improve outcomes for this population. PMID:23634802

Correlation Of Terrestrial gamma flashes, Electric fields, and Lightning strikes (COTEL) in thunderstorms using networked balloon payloads developed by university and community college students

NASA Astrophysics Data System (ADS)

Landry, B. J.; Blair, D.; Causey, J.; Collins, J.; Davis, A.; Fernandez-Kim, V.; Kennedy, J.; Pate, N.; Kearney, C.; Schayer, C.; Turk, E.; Cherry, M. L.; Fava, C.; Granger, D.; Stewart, M.; Guzik, T. G.

2017-12-01

High energy gamma ray flashes from terrestrial sources have been observed by satellites for decades, but the actual mechanism, assumed to be thunderstorm lightning, has yet to be fully characterized. The goal of COTEL, funded by NASA through the University Student Instrument Project (USIP) program, is to correlate in time TGF events, lightning strikes, and electric fields inside of thunderstorms. This will be accomplished using a small network of balloon-borne payloads suspended in and around thunderstorm environments. The payloads will detect and timestamp gamma radiation bursts, lightning strikes, and the intensity of localized electric fields. While in flight, data collected by the payloads will be transmitted to a ground station in real-time and will be analyzed post-flight to investigate potential correlations between lightning, TGFs, and electric fields. The COTEL student team is in its second year of effort having spent the first year developing the basic balloon payloads and ground tracking system. Currently the team is focusing on prototype electric field and gamma radiation detectors. Testing and development of these systems will continue into 2018, and flight operations will take place during the spring 2018 Louisiana thunderstorm season. The presentation, led by undergraduate Physics student Brad Landry, will cover the student team effort in developing the COTEL system, an overview of the system architecture, balloon flight tests conducted to date, preliminary results from prototype detectors, lessons learned for student-led science projects, and future plans.

Birth order and hospitalization for alcohol and narcotics use in Sweden.

PubMed

Barclay, Kieron; Myrskylä, Mikko; Tynelius, Per; Berglind, Daniel; Rasmussen, Finn

2016-10-01

Previous studies have shown that birth order is an important predictor of later life health as well as socioeconomic attainment. In this study, we examine the relationship between birth order and hospitalization for alcohol and narcotics use in Sweden. We study the relationship between birth order and hospitalization related to alcohol and narcotics use before and after the age of 20 using Swedish register data for cohorts born 1987-1994. We apply Cox proportional hazard models and use sibling fixed effects, eliminating confounding by factors shared by the siblings. Before age 20 we find that later born siblings are hospitalized for alcohol use at a higher rate than first-borns, and there is a monotonic increase in the hazard of hospitalization with increasing birth order. Second-borns are hospitalized at a rate 47% higher than first-borns, and third-borns at a rate 65% higher. Similar patterns are observed for hospitalization for narcotics use. After age 20 the pattern is similar, but the association is weaker. These patterns are consistent across various sibling group sizes. Later born siblings are more likely to be hospitalized for both alcohol and narcotics use in Sweden. These birth order effects are substantial in size, and larger than the estimated sex differences for the risk of hospitalization related to alcohol and drug use before age 20, and previous estimates for socioeconomic status differences in alcohol and drug abuse. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Salivary Telomere Length and Lung Function in Adolescents Born Very Preterm: A Prospective Multicenter Study.

PubMed

Hadchouel, Alice; Marchand-Martin, Laetitia; Franco-Montoya, Marie-Laure; Peaudecerf, Laetitia; Ancel, Pierre-Yves; Delacourt, Christophe

2015-01-01

Preterm birth is associated with abnormal respiratory functions throughout life. The mechanisms underlying these long-term consequences are still unclear. Shortening of telomeres was associated with many conditions, such as chronic obstructive pulmonary disease. We aimed to search for an association between telomere length and lung function in adolescents born preterm. Lung function and telomere length were measured in 236 adolescents born preterm and 38 born full-term from the longitudinal EPIPAGE cohort. Associations between telomere length and spirometric indices were tested in univariate and multivariate models accounting for confounding factors in the study population. Airflows were significantly lower in adolescents born preterm than controls; forced expiratory volume in one second was 12% lower in the extremely preterm born group than controls (p<0.001). Lower birth weight, bronchopulmonary dysplasia and postnatal sepsis were significantly associated with lower airflow values. Gender was the only factor that was significantly associated with telomere length. Telomere length correlated with forced expiratory flow 25-75 in the extremely preterm adolescent group in univariate and multivariate analyses (p = 0.01 and p = 0.02, respectively). We evidenced an association between telomere length and abnormal airflow in a population of adolescents born extremely preterm. There was no evident association with perinatal events. This suggests other involved factors, such as a continuing airway oxidative stress leading to persistent inflammation and altered lung function, ultimately increasing susceptibility to chronic obstructive pulmonary disease.

Diabetes is more lethal in Mexicans and Mexican Americans compared to non-Hispanic Whites

PubMed Central

Hunt, Kelly J; Gonzalez, Maria Elena; Lopez, Ruy; Haffner, Steve M; Stern, Michael P; Gonzalez-Villalpando, Clicerio

2012-01-01

Purpose To examine the mortality risk associated with diabetes in the Mexico City Diabetes Study (MCDS) and the San Antonio Heart Study (SAHS). Methods Prospective cohorts conducted 1990-2007 in MCDS and 1979-2000 in SAHS. Mortality risk was examined using Cox proportional hazard models in 1,402 non-Hispanic whites (NHW), 1,907 U.S.-born Mexican Americans (MA), 444 Mexican-born MA, 2,281 Mexico City residents (MCR) between the ages of 35 and 64. Results Age- and sex-adjusted mortality HRs comparing U.S.-born MA, Mexican-born MA and MCR to NHW were 1.09 (95% CI: 0.86, 1.37), 1.23 (95% CI: 0.86, 1.76) and 0.97 (95% CI: 0.77, 1.23), respectively, in non-diabetic individuals; in contrast, mortality risk varied in diabetic individuals with respective HRs of 1.77 (95% CI: 1.20, 2.61), 1.08 (95% CI: 0.59, 1.97) and 2.27 (95% CI: 1.53, 3.35) (interaction p-value=0.0003). Excluding Mexican-born MA and non-diabetic individuals, controlling for medication use, insulin use, fasting glucose levels and duration of diabetes explained a significant proportion of the mortality differential (HRs relative to NHW were 1.31 (95% CI: 0.87, 1.98) in U.S.-born MA and 1.38 (95% CI: 0.89, 2.12) in MCR). Conclusions This study provides evidence that diabetes is more lethal in U.S.-born MA and MCR than in NHW. PMID:21840730

Animal Models of Tick-Borne Hemorrhagic Fever Viruses

PubMed Central

Zivcec, Marko; Safronetz, David; Feldmann, Heinz

2013-01-01

Tick-borne hemorrhagic fever viruses (TBHFV) are detected throughout the African and Eurasian continents and are an emerging or re-emerging threat to many nations. Due to the largely sporadic incidences of these severe diseases, information on human cases and research activities in general have been limited. In the past decade, however, novel TBHFVs have emerged and areas of endemicity have expanded. Therefore, the development of countermeasures is of utmost importance in combating TBHFV as elimination of vectors and interrupting enzootic cycles is all but impossible and ecologically questionable. As in vivo models are the only way to test efficacy and safety of countermeasures, understanding of the available animal models and the development and refinement of animal models is critical in negating the detrimental impact of TBHFVs on public and animal health. PMID:25437041

DOE Office of Scientific and Technical Information (OSTI.GOV)

Esfahani, M. Nasr; Yilmaz, M.; Sonne, M. R.

The trend towards nanomechanical resonator sensors with increasing sensitivity raises the need to address challenges encountered in the modeling of their mechanical behavior. Selecting the best approach in mechanical response modeling amongst the various potential computational solid mechanics methods is subject to controversy. A guideline for the selection of the appropriate approach for a specific set of geometry and mechanical properties is needed. In this study, geometrical limitations in frequency response modeling of flexural nanomechanical resonators are investigated. Deviation of Euler and Timoshenko beam theories from numerical techniques including finite element modeling and Surface Cauchy-Born technique are studied. The resultsmore » provide a limit beyond which surface energy contribution dominates the mechanical behavior. Using the Surface Cauchy-Born technique as the reference, a maximum error on the order of 50 % is reported for high-aspect ratio resonators.« less

Carbon Monoxide Epidemic Among Immigrant Populations: King County, Washington, 2006

PubMed Central

Kwan-Gett, Tao; Hampson, Neil B.; Baer, Atar; Shusterman, Dennis; Shandro, Jamie R.; Duchin, Jeffrey S.

2009-01-01

Objectives. We investigated an outbreak of carbon monoxide (CO) poisoning after a power outage to determine its extent, identify risk factors, and develop prevention measures. Methods. We reviewed medical records and medical examiner reports of patients with CO poisoning or related symptoms during December 15 to 24, 2006. We grouped patients into households exposed concurrently to a single source of CO. Results. Among 259 patients with CO poisoning, 204 cases were laboratory confirmed, 37 were probable, 10 were suspected, and 8 were fatal. Of 86 households studied, 58% (n = 50) were immigrant households from Africa (n = 21), Asia (n = 15), Latin America (n = 10), and the Middle East (n = 4); 34% (n = 29) were US-born households. One percent of households was European (n = 1), and the origin for 7% (n = 6) was unknown. Charcoal was the most common fuel source used among immigrant households (82%), whereas liquid fuel was predominant among US-born households (34%). Conclusions. Educational campaigns to prevent CO poisoning should consider immigrants’ cultural practices and languages and specifically warn against burning charcoal indoors and incorrect ventilation of gasoline- or propane-powered electric generators. PMID:19608962

Theory of diatomic molecules in an external electromagnetic field from first quantum mechanical principles.

PubMed

Sindelka, Milan; Moiseyev, Nimrod

2006-04-27

We study a general problem of the translational/rotational/vibrational/electronic dynamics of a diatomic molecule exposed to an interaction with an arbitrary external electromagnetic field. The theory developed in this paper is relevant to a variety of specific applications, such as alignment or orientation of molecules by lasers, trapping of ultracold molecules in optical traps, molecular optics and interferometry, rovibrational spectroscopy of molecules in the presence of intense laser light, or generation of high order harmonics from molecules. Starting from the first quantum mechanical principles, we derive an appropriate molecular Hamiltonian suitable for description of the center of mass, rotational, vibrational, and electronic molecular motions driven by the field within the electric dipole approximation. Consequently, the concept of the Born-Oppenheimer separation between the electronic and the nuclear degrees of freedom in the presence of an electromagnetic field is introduced. Special cases of the dc/ac-field limits are then discussed separately. Finally, we consider a perturbative regime of a weak dc/ac field, and obtain simple analytic formulas for the associated Born-Oppenheimer translational/rotational/vibrational molecular Hamiltonian.

Ethnic variations in incidence of asthma episodes in England & Wales: national study of 502,482 patients in primary care.

PubMed

Netuveli, Gopalakrishnan; Hurwitz, Brian; Sheikh, Aziz

2005-10-21

Recent studies have demonstrated marked international variations in the prevalence of asthma, but less is known about ethnic variations in asthma epidemiology within individual countries and in particular the impact of migration on risk of developing asthma. Recent within country comparisons have however revealed that despite originating from areas of the world with a low risk for developing asthma, South Asian and Afro-Caribbean people in the UK are significantly (3x and 2x respectively) more likely to be admitted to hospital for asthma related problems than Whites. Using data from the Fourth National Study of Morbidity Statistics in General Practice, a one-percent broadly representative prospective cohort study of consultations in general practice, we investigated ethnic variations in incident asthma consultations (defined as new or first consultations), and compared consultation rates between those born inside and outside the UK (migrant status). Logistic regression models were used to examine the combined effects of ethnicity and migration on asthma incident consultations. Results showed significantly lower new/first asthma consultation rates for Whites than for each of the ethnic minority groups studied (mean age-adjusted consultation rates per 1000 patient-years: Whites 26.4 (95%CI 26.4, 26.4); South Asians 30.4 (95%CI 30.3, 30.5); Afro-Caribbeans 35.1 (95%CI 34.9, 35.3); and Others 27.8 (27.7, 28.0). Within each of these ethnic groups, those born outside of the UK showed consistently lower rates of incident asthma consultations. Modelling the combined effects of ethnic and migrant status revealed that UK-born South Asians and Afro-Caribbeans experienced comparable risks for incident GP consultations for asthma to UK-born Whites. Non-UK born Whites however experienced reduced risks (adjusted OR 0.82, 95%CI 0.69, 0.97) whilst non-UK born South Asians experienced increased risks (adjusted OR 1.33, 95%CI 1.04, 1.70) compared to UK-born Whites. These findings strongly suggest that ethnicity and migration have significant and independent effects on asthma incidence. The known poorer asthma outcomes in UK South Asians and Afro-Caribbeans may in part be explained by the offspring of migrants experiencing an increased risk of developing asthma when compared to UK-born Whites. This is the first study to find heterogeneity for incident asthma consultations in Whites by migrant status.

An analysis of electrical conductivity model in saturated porous media

NASA Astrophysics Data System (ADS)

Cai, J.; Wei, W.; Qin, X.; Hu, X.

2017-12-01

Electrical conductivity of saturated porous media has numerous applications in many fields. In recent years, the number of theoretical methods to model electrical conductivity of complex porous media has dramatically increased. Nevertheless, the process of modeling the spatial conductivity distributed function continues to present challenges when these models used in reservoirs, particularly in porous media with strongly heterogeneous pore-space distributions. Many experiments show a more complex distribution of electrical conductivity data than the predictions derived from the experiential model. Studies have observed anomalously-high electrical conductivity of some low-porosity (tight) formations compared to more- porous reservoir rocks, which indicates current flow in porous media is complex and difficult to predict. Moreover, the change of electrical conductivity depends not only on the pore volume fraction but also on several geometric properties of the more extensive pore network, including pore interconnection and tortuosity. In our understanding of electrical conductivity models in porous media, we study the applicability of several well-known methods/theories to electrical characteristics of porous rocks as a function of pore volume, tortuosity and interconnection, to estimate electrical conductivity based on the micro-geometrical properties of rocks. We analyze the state of the art of scientific knowledge and practice for modeling porous structural systems, with the purpose of identifying current limitations and defining a blueprint for future modeling advances. We compare conceptual descriptions of electrical current flow processes in pore space considering several distinct modeling approaches. Approaches to obtaining more reasonable electrical conductivity models are discussed. Experiments suggest more complex relationships between electrical conductivity and porosity than experiential models, particularly in low-porosity formations. However, the available theoretical models combined with simulations do provide insight to how microscale physics affects macroscale electrical conductivity in porous media.

Spacelike brane actions.

PubMed

Hashimoto, Koji; Ho, Pei-Ming; Wang, John E

2003-04-11

We derive effective actions for "spacelike branes" (S-branes) and find a solution describing the formation of fundamental strings in the rolling tachyon background. The S-brane action is a Dirac-Born-Infeld action for Euclidean world volumes defined in the context of time-dependent tachyon condensation of non-BPS (Bogomol'nyi-Prasad-Sommerfield) branes. It includes gauge fields and, in particular, a scalar field associated with translation along the time direction. We show that the BIon spike solutions constructed in this system correspond to the production of a confined electric flux tube (a fundamental string) at late time of the rolling tachyon.

Environmental testing of high Tc superconductive thermal isolators for space-borne cryogenic detector systems

NASA Technical Reports Server (NTRS)

Wise, Stephanie A.; Buckley, John D.; Randolf, Henry W.; Verbelyi, Darren; Haertling, Gene H.; Hooker, Matthew W.; Selim, Raouf; Caton, Randall

1992-01-01

Thick films of superconductive material on low thermal conductivity substrates (e.g., yttria-stabilized zirconia and fused silica) are considered as a replacement for the existing electrical connections between the detector array and data acquisition and storage electronics in the cryogenic detector systems being developed by NASA. The paper describes some of the design constraints on the superconducting device and presents results of a preliminary analysis of the effects of vibration, gamma irradiation, and long-term exposure to high vacuum and liquid nitrogen encountered in operating such a device in space.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiegelmann, T.; Solanki, S. K.; Barthol, P.

Magneto-static models may overcome some of the issues facing force-free magnetic field extrapolations. So far they have seen limited use and have faced problems when applied to quiet-Sun data. Here we present a first application to an active region. We use solar vector magnetic field measurements gathered by the IMaX polarimeter during the flight of the Sunrise balloon-borne solar observatory in 2013 June as boundary conditions for a magneto-static model of the higher solar atmosphere above an active region. The IMaX data are embedded in active region vector magnetograms observed with SDO /HMI. This work continues our magneto-static extrapolation approach,more » which was applied earlier to a quiet-Sun region observed with Sunrise I. In an active region the signal-to-noise-ratio in the measured Stokes parameters is considerably higher than in the quiet-Sun and consequently the IMaX measurements of the horizontal photospheric magnetic field allow us to specify the free parameters of the model in a special class of linear magneto-static equilibria. The high spatial resolution of IMaX (110–130 km, pixel size 40 km) enables us to model the non-force-free layer between the photosphere and the mid-chromosphere vertically by about 50 grid points. In our approach we can incorporate some aspects of the mixed beta layer of photosphere and chromosphere, e.g., taking a finite Lorentz force into account, which was not possible with lower-resolution photospheric measurements in the past. The linear model does not, however, permit us to model intrinsic nonlinear structures like strongly localized electric currents.« less

Shock wave polarizations and optical metrics in the Born and the Born–Infeld electrodynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minz, Christoph, E-mail: christoph.minz@alumni.tu-berlin.de; Borzeszkowski, Horst-Heino von, E-mail: borzeszk@mailbox.tu-berlin.de; Chrobok, Thoralf, E-mail: tchrobok@mailbox.tu-berlin.de

We analyze the behavior of shock waves in nonlinear theories of electrodynamics. For this, by use of generalized Hadamard step functions of increasing order, the electromagnetic potential is developed in a series expansion near the shock wave front. This brings about a corresponding expansion of the respective electromagnetic field equations which allows for deriving relations that determine the jump coefficients in the expansion series of the potential. We compute the components of a suitable gauge-normalized version of the jump coefficients given for a prescribed tetrad compatible with the shock front foliation. The solution of the first-order jump relations shows that,more » in contrast to linear Maxwell’s electrodynamics, in general the propagation of shock waves in nonlinear theories is governed by optical metrics and polarization conditions describing the propagation of two differently polarized waves (leading to a possible appearance of birefringence). In detail, shock waves are analyzed in the Born and Born–Infeld theories verifying that the Born–Infeld model exhibits no birefringence and the Born model does. The obtained results are compared to those ones found in literature. New results for the polarization of the two different waves are derived for Born-type electrodynamics.« less

How Do Social Factors Explain Outcomes in Non–Small-Cell Lung Cancer Among Hispanics in California? Explaining the Hispanic Paradox

PubMed Central

Patel, Manali I.; Schupp, Clayton W.; Gomez, Scarlett L.; Chang, Ellen T.; Wakelee, Heather A.

2013-01-01

Purpose Hispanics in the United States have lower age-adjusted mortality resulting from non–small-cell lung cancer (NSCLC) compared with non-Hispanic whites (NHWs). The purpose of this study was to evaluate individual, clinical, and neighborhood factors in survival among Hispanics with NSCLC. Patients and Methods We performed a retrospective analysis of NHWs and Hispanics with NSCLC between 1998 and 2007 in the California Cancer Registry (follow-up to December 2009). Kaplan-Meier curves depict survival by nativity for Hispanics with NSCLC. Cox proportional hazards models estimated hazard of mortality by race with adjustment for individual (age, sex, marital status), clinical (histologic grade, surgery, irradiation, chemotherapy), and neighborhood factors (neighborhood socioeconomic status, ethnic enclave). Results We included 14,280 Hispanic patients with NSCLC. Foreign-born Hispanics had 15% decreased risk of disease-specific mortality resulting from NSCLC compared with NHWs (hazard ratio [HR], 0.85; 95% CI, 0.83 to 0.88) after adjustment for individual, clinical, and neighborhood factors. After adjustment for individual factors, compared with US-born Hispanics, foreign-born Hispanics had 10% decreased risk of disease-specific mortality (HR, 0.90; 95% CI, 0.87 to 0.96). Clinical and neighborhood factors slightly moderated the survival benefit for foreign-born patients. A modestly more pronounced survival advantage was seen for foreign-born Hispanics living in low socioeconomic and high Hispanic enclave neighborhoods as compared with US-born Hispanics (HR, 0.86; 95% CI, 0.81 to 0.90). Conclusion Foreign-born Hispanics with NSCLC have a decreased risk of disease-specific mortality compared with NHWs and US-born Hispanics with NSCLC. Neighborhood factors slightly moderate this survival advantage. This survival advantage is slightly more pronounced in lower socioeconomic and higher Hispanic enclave neighborhoods. PMID:23960183

Suburban migration and the birth outcome of Chicago-born white and African-American women: the merit of the healthy migrant theory?

PubMed

Collins, James W; Rankin, Kristin M; Janowiak, Christine M

2013-11-01

The healthy migrant theory posits that women who migrate before pregnancy are intrinsically healthier and therefore have better birth outcomes than those who don't move. Objective. To determine whether migration to the suburbs is associated with lower rates of preterm (<37 weeks) birth among Chicago-born White and African-American mothers. We performed stratified and multilevel logistic regression analyses on an Illinois transgenerational dataset of non-Latino White and African-American infants (1989-1991) and their mothers (1956-1976) with appended US census income information. Forty percent of Chicago-born White mothers (N = 45,135) migrated to Suburban Cook County and 30 % migrated to the more geographically distant collar counties. In contrast, 10 % of Chicago-born African-American mothers (N = 41,221) migrated to Suburban Cook and only two percent migrated to the collar counties. Chicago-born White and African-American migrant mothers to Suburban Cook County had lower preterm birth rates than their non-migrant counterparts; RR = 0.8 (0.8-0.9) and 0.8 (0.7-0.8), respectively. When neighborhood income was singularly taken into account, the protective association of suburban migration and preterm birth disappeared among Chicago-born Whites. In race-specific multilevel multivariate regression models which included neighborhood income, the adjusted odds ratio of preterm birth, low birth weight, and small for gestational-age for Chicago-born White and African-American migrant (compared to non-migrant) mothers approximated unity. Neighborhood income underlies the protective association of suburban migration and birth outcome among Chicago-born White and African-American mothers. These findings do not support the healthy migrant hypothesis of reproductive outcome.

Breast cancer diagnosis and mortality by tumor stage and migration background in a nationwide cohort study in Sweden.

PubMed

Abdoli, Gholamreza; Bottai, Matteo; Sandelin, Kerstin; Moradi, Tahereh

2017-02-01

Survival in breast cancer patients has steadily increased over the years, but with considerable disparities between individuals with different migration background and social position. We explored differences in diagnosis and all-cause mortality in breast cancer patients by stage of disease at the time of diagnosis and by country of birth, while considering the effect of comorbidity, regional and socio-demographic factors. We used Swedish national registers to follow a cohort of 35,268 patients (4232 foreign-born) with breast cancer between 2004 and 2009 in Sweden. We estimated relative risk ratio (RRR) for diagnosis, hazard ratio (HR) for all-cause mortality and relative excess rate (RER) for breast cancer mortality using multinomial logistic regression models, multivariable Cox proportional hazard, and Poisson regression, respectively. We observed 4178 deaths due to any causes. Among them 418 women were born abroad. Foreign-born patients were on average 3 years younger at the time of breast cancer diagnosis and had higher risk of stage II tumors compared with Sweden-born women (RRR = 1.09, 95% CI 1.00-1.19). Risk of dying was 20% higher in foreign-born compared with Sweden-born breast cancer patients, if the tumor was diagnosed at stages III-IV after adjustment for age at diagnosis, education, county of residence and Charlson's comorbidity index (HR = 1.20, 95% CI 0.95-1.51 and RER = 1.21, 95% CI 0.95-1.55). The worse prognosis in foreign-born patients with advanced tumors compared with Sweden-born patients is not explained by educational level or comorbidity. The reasons behind the observed disparities should be further studied. Copyright © 2016 Elsevier Ltd. All rights reserved.

Breast and cervical cancer screening: impact of health insurance status, ethnicity, and nativity of Latinas.

PubMed

Rodríguez, Michael A; Ward, Lisa M; Pérez-Stable, Eliseo J

2005-01-01

Although rates of cancer screening for Latinas are lower than for non-Latina whites, little is known about how insurance status, ethnicity, and nativity interact to influence these disparities. Using a large statewide database, our study examined the relationship between breast and cervical cancer screening rates and socioeconomic and health insurance status among foreign-born Latinas, US-born Latinas, and non-Latina whites in California. Data from the1998 California Women's Health Survey (CWHS) were analyzed (n = 3,340) using multiple logistic regression models. Utilization rates of mammography, clinical breast examinations, and Papanicolaou (Pap) smear screening among foreign-born Latinas, US-born Latinas, and non-Latina whites were the outcome measures. Foreign-born Latinas had the highest rates of never receiving mammography, clinical breast examinations, and Pap smears (21%, 24%, 9%, respectively) compared with US-born Latinas (12%, 11%, 7%, respectively) and non-Latina whites (9%, 5%, 2%, respectively). After controlling for socioeconomic factors, foreign-born Latinas were more likely to report mammography use in the previous 2 years and Pap smear in the previous 3 years than non-Latina whites. Lack of health insurance coverage was the strongest independent predictor of low utilization rates for mammography (odds ratio [OR] = 2.05; 95% confidence interval [CI], 1.53-2.76), clinical breast examinations (OR = 2.29; 95% CI, 1.80-2.90) and Pap smears (OR = 2.89; 95% CI, 2.17-3.85.) Breast and cervical cancer screening rates vary by ethnicity and nativity, with foreign-born Latinas experiencing the highest rates of never being screened. After accounting for socioeconomic factors, differences by ethnicity and nativity are reversed or eliminated. Lack of health insurance coverage remains the strongest predictor of cancer screening underutilization.

Pregnancy during breast cancer: does a mother's parity status modify an offspring's mortality risk?

PubMed

Simonella, Leonardo; Verkooijen, Helena M; Edgren, Gustaf; Liu, Jenny; Hui, Miao; Salim, Agus; Czene, Kamila; Hartman, Mikael

2014-07-01

To assess whether children born to primiparous women around the time of a breast cancer diagnosis have an increased mortality risk. From the merged Swedish Multi-Generation and Cancer Registers, we identified 49,750 eligible children whose mother was diagnosed with breast cancer between 1958 and 2010. Mortality rates in offspring were compared to the background population using standardized mortality ratios (SMR), adjusted for calendar year of birth, attained age, and sex, and calculated for each category of timing of delivery (before, around, or after mother's diagnosis) and mother's parity status. Hazard ratios were assessed using a Cox proportional hazards model and adjusted for socioeconomic status, year of birth and mother's age at birth. Children born to a primiparous woman around a breast cancer diagnosis had a mortality rate five times greater than the background population (SMR 5.26, 95 % CI 1.93-11.5), whereas children born to a multiparous woman had a twofold increase (SMR 2.40, 95 % CI 1.10-4.55). Children of primiparous women born around diagnosis had an adjusted hazard ratio fourfold to that of children of primiparous women born before their mother's diagnosis (HR 4.29, 95 % CI 1.68-8.91), whereas hazard ratios for children of primiparous or multiparous women born at other times were not statistically significant. Children born to primiparous women around a breast cancer diagnosis have an increased relative mortality risk. Although relative risk is increased, in absolute terms children born from a cancer complicated pregnancy do relatively well. Additional investigations are needed to elucidate the reason(s) underlying this observation before the information can be used to inform patient counseling and clinical care.

The role of remote sensing and GIS for spatial prediction of vector-borne diseases transmission: a systematic review.

PubMed

Palaniyandi, M

2012-12-01

There have been several attempts made to the appreciation of remote sensing and GIS for the study of vectors, biodiversity, vector presence, vector abundance and the vector-borne diseases with respect to space and time. This study was made for reviewing and appraising the potential use of remote sensing and GIS applications for spatial prediction of vector-borne diseases transmission. The nature of the presence and the abundance of vectors and vector-borne diseases, disease infection and the disease transmission are not ubiquitous and are confined with geographical, environmental and climatic factors, and are localized. The presence of vectors and vector-borne diseases is most complex in nature, however, it is confined and fueled by the geographical, climatic and environmental factors including man-made factors. The usefulness of the present day availability of the information derived from the satellite data including vegetation indices of canopy cover and its density, soil types, soil moisture, soil texture, soil depth, etc. is integrating the information in the expert GIS engine for the spatial analysis of other geoclimatic and geoenvironmental variables. The present study gives the detailed information on the classical studies of the past and present, and the future role of remote sensing and GIS for the vector-borne diseases control. The ecological modeling directly gives us the relevant information to understand the spatial variation of the vector biodiversity, vector presence, vector abundance and the vector-borne diseases in association with geoclimatic and the environmental variables. The probability map of the geographical distribution and seasonal variations of horizontal and vertical distribution of vector abundance and its association with vector -borne diseases can be obtained with low cost remote sensing and GIS tool with reliable data and speed.

A quasi-static model of global atmospheric electricity. I - The lower atmosphere

NASA Technical Reports Server (NTRS)

Hays, P. B.; Roble, R. G.

1979-01-01

A quasi-steady model of global lower atmospheric electricity is presented. The model considers thunderstorms as dipole electric generators that can be randomly distributed in various regions and that are the only source of atmospheric electricity and includes the effects of orography and electrical coupling along geomagnetic field lines in the ionosphere and magnetosphere. The model is used to calculate the global distribution of electric potential and current for model conductivities and assumed spatial distributions of thunderstorms. Results indicate that large positive electric potentials are generated over thunderstorms and penetrate to ionospheric heights and into the conjugate hemisphere along magnetic field lines. The perturbation of the calculated electric potential and current distributions during solar flares and subsequent Forbush decreases is discussed, and future measurements of atmospheric electrical parameters and modifications of the model which would improve the agreement between calculations and measurements are suggested.

Parameterization and Sensitivity Analysis of a Complex Simulation Model for Mosquito Population Dynamics, Dengue Transmission, and Their Control

PubMed Central

Ellis, Alicia M.; Garcia, Andres J.; Focks, Dana A.; Morrison, Amy C.; Scott, Thomas W.

2011-01-01

Models can be useful tools for understanding the dynamics and control of mosquito-borne disease. More detailed models may be more realistic and better suited for understanding local disease dynamics; however, evaluating model suitability, accuracy, and performance becomes increasingly difficult with greater model complexity. Sensitivity analysis is a technique that permits exploration of complex models by evaluating the sensitivity of the model to changes in parameters. Here, we present results of sensitivity analyses of two interrelated complex simulation models of mosquito population dynamics and dengue transmission. We found that dengue transmission may be influenced most by survival in each life stage of the mosquito, mosquito biting behavior, and duration of the infectious period in humans. The importance of these biological processes for vector-borne disease models and the overwhelming lack of knowledge about them make acquisition of relevant field data on these biological processes a top research priority. PMID:21813844

Extensive ionic partitioning in interfaces that membranous and biomimetic surfaces form with electrolytes: Antitheses of the gold-electrolyte interface

NASA Astrophysics Data System (ADS)

Chilcott, Terry; Guo, Chuan; Coster, Hans

2013-04-01

Maxwell-Wagner modeling of electrical impedance measurements of tetradecane-electrolyte systems yielded three interfacial layers between the tetradecane layer and the bulk electrolytes of concentration ranging from 1-300 mM KCl whereas the gold-electrolyte system yielded only one layer. The conductivity and thickness for the surface layer were orders of magnitude different from that expected for the Gouy-Chapman layer and did not reflect dependencies of the Debye length on concentration. Conductivity values for the three layers were less than those of the bulk electrolyte but exhibited a dependency on concentration similar to that expected for the bulk. Thickness values for the layers indicate an interface extending ~106 Å into the bulk electrolyte, which contrasts with the gold-electrolyte interface that extended only 20-30 Å into the bulk. Maxwell-Wagner characterizations of both interfaces were consistent with spatial distributions of ionic partitioning arising from the Born energy as determined by the dielectric properties of the substrates and electrolyte. The distributions for the membranous and silicon interfaces were similar but the antitheses of that for the gold interface.

Halo-induced large enhancement of soft dipole excitation of 11Li observed via proton inelastic scattering

NASA Astrophysics Data System (ADS)

Tanaka, J.; Kanungo, R.; Alcorta, M.; Aoi, N.; Bidaman, H.; Burbadge, C.; Christian, G.; Cruz, S.; Davids, B.; Diaz Varela, A.; Even, J.; Hackman, G.; Harakeh, M. N.; Henderson, J.; Ishimoto, S.; Kaur, S.; Keefe, M.; Krücken, R.; Leach, K. G.; Lighthall, J.; Padilla Rodal, E.; Randhawa, J. S.; Ruotsalainen, P.; Sanetullaev, A.; Smith, J. K.; Workman, O.; Tanihata, I.

2017-11-01

Proton inelastic scattering off a neutron halo nucleus, 11Li, has been studied in inverse kinematics at the IRIS facility at TRIUMF. The aim was to establish a soft dipole resonance and to obtain its dipole strength. Using a high quality 66 MeV 11Li beam, a strongly populated excited state in 11Li was observed at Ex = 0.80 ± 0.02 MeV with a width of Γ = 1.15 ± 0.06 MeV. A DWBA (distorted-wave Born approximation) analysis of the measured differential cross section with isoscalar macroscopic form factors leads us to conclude that this observed state is excited in an electric dipole (E1) transition. Under the assumption of isoscalar E1 transitions, the strength is evaluated to be extremely large amounting to 30 ∼ 296 Weisskopf units, exhausting 2.2% ∼ 21% of the isoscalar E1 energy-weighted sum rule (EWSR) value. The large observed strength originates from the halo and is consistent with the simple di-neutron model of 11Li halo.

Effect of eczema on the association between season of birth and food allergy in Japanese children.

PubMed

Kusunoki, Takashi; Morimoto, Takeshi; Sakuma, Mio; Mukaida, Kumiko; Yasumi, Takahiro; Nishikomori, Ryuta; Heike, Toshio

2013-02-01

Food allergy (FA) in childhood has been shown to be more prevalent in those born in autumn and winter. The mechanisms of this season-of-birth effect remain unclear, although shortage of vitamin D during infancy has been considered one possible mechanism. The purpose of this study was to investigate the effect of eczema on the season-of-birth effect on FA in infancy. A questionnaire survey on the prevalence of allergic diseases was completed by the parents of 14 669 Japanese schoolchildren, aged 7-15 years, in Kyoto City, Japan. Logistic regression models were constructed to compare the prevalence of FA in infancy according to season of birth. Those born in autumn and winter had a significantly higher prevalence of FA in infancy compared to those born in spring and summer in a multivariate model (4.8% vs 3.6%, P = 0.001). The difference, however, was no longer significant when eczema before 6 months was included as either an additional or only confounding factor. The difference among those with and without eczema before 6 months was further analyzed, and it was found that, in both groups, there was no difference between those born in spring and summer and those born in autumn and winter. The season-of-birth effect on FA in infancy was significantly affected by the existence of eczema before 6 months in Japanese children. Eczema before 6 months may be the factor directly related to the season-of-birth effect on FA in infancy. © 2012 The Authors. Pediatrics International © 2012 Japan Pediatric Society.

Ronald N. Bracewell: An Appreciation

NASA Astrophysics Data System (ADS)

Thompson, A. Richard; Frater, Robert H.

2010-11-01

Ronald Newbold Bracewell (1921-2007) made fundamental contributions to the development of radio astronomy in the areas of interferometry, signal processing, and imaging, and also to tomography, various areas of data analysis, and the understanding of Fourier transforms. He was born in Sydney, Australia, and received a B.Sc. degree in mathematics and physics, and B.E. and M.E. degrees in electrical engineering from the University of Sydney, and his Ph.D. from the University of Cambridge, U.K., for research on the ionosphere. In 1949 he joined the Radiophysics Laboratory of CSIRO, where he became interested in radio astronomy. In 1955 he moved to Stanford University, California, where he became Lewis M. Terman Professor of Electrical Engineering. He retired from teaching in 1991, but continued to be active in radio astronomy and other applications of imaging techniques, etc. During his career he published ten books and more than 250 papers. Honors that he received include the Duddell Premium of the Institute of Electrical Engineers, London, the Hertz Medal of the IEEE, and the Order of Australia. For his work on imaging in tomography he was elected to Associate Membership of the Institute of Medicine of the U.S. National Academy of Sciences.

In situ measurements of the Runaway Breakdown (RB) on Aragats mountain

NASA Astrophysics Data System (ADS)

Chilingarian, A.; Hovsepyan, G.; Mailyan, B.

2017-12-01

Acceleration and multiplication of the cosmic ray electrons by strong electric fields in the thundercloud are well-established phenomena comprising the core of the atmospheric high-energy physics. The majority of experimental data on particle acceleration in the thunderclouds comes from space-born experiments detecting Terrestrial Gamma flashes (TGFs) and from networks of particle detectors located on the earth's surface observing Thunderstorm Ground Enhancements (TGEs). Models for explaining both TGF and TGE are based on the concept of a Runaway Breakdown (RB) introduced by A. Gurevich. Prove of these models requires registration of the electromagnetic avalanches developing in the thundercloud and reaching the earth's surface. Unfortunately due to high location of cloud and fast attenuation of electrons in the atmosphere the registration of such an avalanches are very rare. On Aragats mountain in Armenia, where the cloud location is very low we observe several TGE events with sizable electron contribution. We present direct measurements of such an avalanches lasting less than a microsecond; hundreds of such avalanches comprise a TGE lasting few minutes. We recovered as well the differential energy spectra of electron and gamma ray content of avalanches. The abrupt termination of the particle flux by nearby lightning indicates that RB process precedes (initiates) the lightning flash.

Demand forecasting of electricity in Indonesia with limited historical data

NASA Astrophysics Data System (ADS)

Dwi Kartikasari, Mujiati; Rohmad Prayogi, Arif

2018-03-01

Demand forecasting of electricity is an important activity for electrical agents to know the description of electricity demand in future. Prediction of demand electricity can be done using time series models. In this paper, double moving average model, Holt’s exponential smoothing model, and grey model GM(1,1) are used to predict electricity demand in Indonesia under the condition of limited historical data. The result shows that grey model GM(1,1) has the smallest value of MAE (mean absolute error), MSE (mean squared error), and MAPE (mean absolute percentage error).

A geographical information system-based multicriteria evaluation to map areas at risk for Rift Valley fever vector-borne transmission in Italy.

PubMed

Tran, A; Ippoliti, C; Balenghien, T; Conte, A; Gely, M; Calistri, P; Goffredo, M; Baldet, T; Chevalier, V

2013-11-01

Rift Valley fever (RVF) is a severe mosquito-borne disease that is caused by a Phlebovirus (Bunyaviridae) and affects domestic ruminants and humans. Recently, its distribution widened, threatening Europe. The probability of the introduction and large-scale spread of Rift Valley fever virus (RVFV) in Europe is low, but localized RVF outbreaks may occur in areas where populations of ruminants and potential vectors are present. In this study, we assumed the introduction of the virus into Italy and focused on the risk of vector-borne transmission of RVFV to three main European potential hosts (cattle, sheep and goats). Five main potential mosquito vectors belonging to the Culex and Aedes genera that are present in Italy were identified in a literature review. We first modelled the geographical distribution of these five species based on expert knowledge and using land cover as a proxy of mosquito presence. The mosquito distribution maps were compared with field mosquito collections from Italy to validate the model. Next, the risk of RVFV transmission was modelled using a multicriteria evaluation (MCE) approach, integrating expert knowledge and the results of a literature review on host sensitivity and vector competence, feeding behaviour and abundance. A sensitivity analysis was performed to assess the robustness of the results with respect to expert choices. The resulting maps include (i) five maps of the vector distribution, (ii) a map of suitable areas for vector-borne transmission of RVFV and (iii) a map of the risk of RVFV vector-borne transmission to sensitive hosts given a viral introduction. Good agreement was found between the modelled presence probability and the observed presence or absence of each vector species. The resulting RVF risk map highlighted strong spatial heterogeneity and could be used to target surveillance. In conclusion, the geographical information system (GIS)-based MCE served as a valuable framework and a flexible tool for mapping the areas at risk of a pathogen that is currently absent from a region. © 2013 Blackwell Verlag GmbH.

Approximate solutions of acoustic 3D integral equation and their application to seismic modeling and full-waveform inversion

NASA Astrophysics Data System (ADS)

Malovichko, M.; Khokhlov, N.; Yavich, N.; Zhdanov, M.

2017-10-01

Over the recent decades, a number of fast approximate solutions of Lippmann-Schwinger equation, which are more accurate than classic Born and Rytov approximations, were proposed in the field of electromagnetic modeling. Those developments could be naturally extended to acoustic and elastic fields; however, until recently, they were almost unknown in seismology. This paper presents several solutions of this kind applied to acoustic modeling for both lossy and lossless media. We evaluated the numerical merits of those methods and provide an estimation of their numerical complexity. In our numerical realization we use the matrix-free implementation of the corresponding integral operator. We study the accuracy of those approximate solutions and demonstrate, that the quasi-analytical approximation is more accurate, than the Born approximation. Further, we apply the quasi-analytical approximation to the solution of the inverse problem. It is demonstrated that, this approach improves the estimation of the data gradient, comparing to the Born approximation. The developed inversion algorithm is based on the conjugate-gradient type optimization. Numerical model study demonstrates that the quasi-analytical solution significantly reduces computation time of the seismic full-waveform inversion. We also show how the quasi-analytical approximation can be extended to the case of elastic wavefield.

Bayesian data assimilation provides rapid decision support for vector-borne diseases.

PubMed

Jewell, Chris P; Brown, Richard G

2015-07-06

Predicting the spread of vector-borne diseases in response to incursions requires knowledge of both host and vector demographics in advance of an outbreak. Although host population data are typically available, for novel disease introductions there is a high chance of the pathogen using a vector for which data are unavailable. This presents a barrier to estimating the parameters of dynamical models representing host-vector-pathogen interaction, and hence limits their ability to provide quantitative risk forecasts. The Theileria orientalis (Ikeda) outbreak in New Zealand cattle demonstrates this problem: even though the vector has received extensive laboratory study, a high degree of uncertainty persists over its national demographic distribution. Addressing this, we develop a Bayesian data assimilation approach whereby indirect observations of vector activity inform a seasonal spatio-temporal risk surface within a stochastic epidemic model. We provide quantitative predictions for the future spread of the epidemic, quantifying uncertainty in the model parameters, case infection times and the disease status of undetected infections. Importantly, we demonstrate how our model learns sequentially as the epidemic unfolds and provide evidence for changing epidemic dynamics through time. Our approach therefore provides a significant advance in rapid decision support for novel vector-borne disease outbreaks. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Chaotic sources of noise in machine acoustics

NASA Astrophysics Data System (ADS)

Moon, F. C., Prof.; Broschart, Dipl.-Ing. T.

1994-05-01

In this paper a model is posited for deterministic, random-like noise in machines with sliding rigid parts impacting linear continuous machine structures. Such problems occur in gear transmission systems. A mathematical model is proposed to explain the random-like structure-borne and air-borne noise from such systems when the input is a periodic deterministic excitation of the quasi-rigid impacting parts. An experimental study is presented which supports the model. A thin circular plate is impacted by a chaotically vibrating mass excited by a sinusoidal moving base. The results suggest that the plate vibrations might be predicted by replacing the chaotic vibrating mass with a probabilistic forcing function. Prechaotic vibrations of the impacting mass show classical period doubling phenomena.

Response latencies are alive and well for identifying fakers on a self-report personality inventory: A reconsideration of van Hooft and Born (2012).

PubMed

Holden, Ronald R; Lambert, Christine E

2015-12-01

Van Hooft and Born (Journal of Applied Psychology 97:301-316, 2012) presented data challenging both the correctness of a congruence model of faking on personality test items and the relative merit (i.e., effect size) of response latencies for identifying fakers. We suggest that their analysis of response times was suboptimal, and that it followed neither from a congruence model of faking nor from published protocols on appropriately filtering the noise in personality test item answering times. Using new data and following recommended analytic procedures, we confirmed the relative utility of response times for identifying personality test fakers, and our obtained results, again, reinforce a congruence model of faking.

2-D Fused Image Reconstruction approach for Microwave Tomography: a theoretical assessment using FDTD Model

PubMed Central

Bindu, G.; Semenov, S.

2013-01-01

This paper describes an efficient two-dimensional fused image reconstruction approach for Microwave Tomography (MWT). Finite Difference Time Domain (FDTD) models were created for a viable MWT experimental system having the transceivers modelled using thin wire approximation with resistive voltage sources. Born Iterative and Distorted Born Iterative methods have been employed for image reconstruction with the extremity imaging being done using a differential imaging technique. The forward solver in the imaging algorithm employs the FDTD method of solving the time domain Maxwell’s equations with the regularisation parameter computed using a stochastic approach. The algorithm is tested with 10% noise inclusion and successful image reconstruction has been shown implying its robustness. PMID:24058889

Early Preterm Birth Across Generations Among Whites and African-Americans: A Population-Based Study.

PubMed

Dorner, Rebecca A; Rankin, Kristin M; Collins, James W

2017-11-01

Objectives To determine the extent to which non-Latina White and African-American mother's gestational age is associated with extremely early (<30 weeks), modestly early (30-33 weeks), and late (34-36 weeks) infant preterm birth (PTB) rates. Methods Race-specific stratified and multivariable logistic regression analyses were performed on the Illinois Transgenerational Birth File of non-Latino White and African-American infants (born 1989-1991) and their mothers (born 1956-1976). Results White mothers (n = 184) born at <30 weeks had a greater extremely early infant PTB rate than White mothers (n = 131,980) born at term: 1.6 versus 0.5%, respectively; RR = 3.6 (1.2, 11.0). African-American mothers (n = 269) born at <30 weeks had a greater extremely early infant PTB rate than African-American mothers (n = 34,885) born at term: 4.1 versus 2.1%, respectively; RR = 2.0 (1.1, 3.6). In logistic regression models the adjusted (controlling for maternal age, education, parity, prenatal care, marital status, and cigarette smoking) OR of extremely early PTB for White and African-American mothers born <30 (compared to ≥37) weeks equaled 4.0 (1.2, 12.6) and 2.3 (1.2, 4.3), respectively. The adjusted OR of modestly early PTB for White and African-American mothers born 30-33 (compared to ≥37) weeks equaled 1.6 (1.0, 2.5) and 1.3 (0.9, 1.7), respectively. The adjusted OR of late PTB for White and African-American mothers born 34-36 (compared to ≥37) weeks equaled 1.2 (1.0, 1.3) and 1.1 (1.0, 1.2), respectively. Conclusions A generational association of extremely early, but not modestly early or late, PTB exists among non-Latino Whites and African-Americans.

Suboptimal care and maternal mortality among foreign-born women in Sweden: maternal death audit with application of the ‘migration three delays’ model

PubMed Central

2014-01-01

Background Several European countries report differences in risk of maternal mortality between immigrants from low- and middle-income countries and host country women. The present study identified suboptimal factors related to care-seeking, accessibility, and quality of care for maternal deaths that occurred in Sweden from 1988–2010. Methods A subset of maternal death records (n = 75) among foreign-born women from low- and middle-income countries and Swedish-born women were audited using structured implicit review. One case of foreign-born maternal death was matched with two native born Swedish cases of maternal death. An assessment protocol was developed that applied both the ‘migration three delays’ framework and a modified version of the Confidential Enquiry from the United Kingdom. The main outcomes were major and minor suboptimal factors associated with maternal death in this high-income, low-maternal mortality context. Results Major and minor suboptimal factors were associated with a majority of maternal deaths and significantly more often to foreign-born women (p = 0.01). The main delays to care-seeking were non-compliance among foreign-born women and communication barriers, such as incongruent language and suboptimal interpreter system or usage. Inadequate care occurred more often among the foreign-born (p = 0.04), whereas delays in consultation/referral and miscommunication between health care providers where equally common between the two groups. Conclusions Suboptimal care factors, major and minor, were present in more than 2/3 of maternal deaths in this high-income setting. Those related to migration were associated to miscommunication, lack of professional interpreters, and limited knowledge about rare diseases and pregnancy complications. Increased insight into a migration perspective is advocated for maternity clinicians who provide care to foreign-born women. PMID:24725307

T2N as a new tool for robust electrophysiological modeling demonstrated for mature and adult-born dentate granule cells

PubMed Central

Mongiat, Lucas Alberto; Schwarzacher, Stephan Wolfgang

2017-01-01

Compartmental models are the theoretical tool of choice for understanding single neuron computations. However, many models are incomplete, built ad hoc and require tuning for each novel condition rendering them of limited usability. Here, we present T2N, a powerful interface to control NEURON with Matlab and TREES toolbox, which supports generating models stable over a broad range of reconstructed and synthetic morphologies. We illustrate this for a novel, highly detailed active model of dentate granule cells (GCs) replicating a wide palette of experiments from various labs. By implementing known differences in ion channel composition and morphology, our model reproduces data from mouse or rat, mature or adult-born GCs as well as pharmacological interventions and epileptic conditions. This work sets a new benchmark for detailed compartmental modeling. T2N is suitable for creating robust models useful for large-scale networks that could lead to novel predictions. We discuss possible T2N application in degeneracy studies. PMID:29165247

Improvement of Disease Prediction and Modeling through the Use of Meteorological Ensembles: Human Plague in Uganda

PubMed Central

Moore, Sean M.; Monaghan, Andrew; Griffith, Kevin S.; Apangu, Titus; Mead, Paul S.; Eisen, Rebecca J.

2012-01-01

Climate and weather influence the occurrence, distribution, and incidence of infectious diseases, particularly those caused by vector-borne or zoonotic pathogens. Thus, models based on meteorological data have helped predict when and where human cases are most likely to occur. Such knowledge aids in targeting limited prevention and control resources and may ultimately reduce the burden of diseases. Paradoxically, localities where such models could yield the greatest benefits, such as tropical regions where morbidity and mortality caused by vector-borne diseases is greatest, often lack high-quality in situ local meteorological data. Satellite- and model-based gridded climate datasets can be used to approximate local meteorological conditions in data-sparse regions, however their accuracy varies. Here we investigate how the selection of a particular dataset can influence the outcomes of disease forecasting models. Our model system focuses on plague (Yersinia pestis infection) in the West Nile region of Uganda. The majority of recent human cases have been reported from East Africa and Madagascar, where meteorological observations are sparse and topography yields complex weather patterns. Using an ensemble of meteorological datasets and model-averaging techniques we find that the number of suspected cases in the West Nile region was negatively associated with dry season rainfall (December-February) and positively with rainfall prior to the plague season. We demonstrate that ensembles of available meteorological datasets can be used to quantify climatic uncertainty and minimize its impacts on infectious disease models. These methods are particularly valuable in regions with sparse observational networks and high morbidity and mortality from vector-borne diseases. PMID:23024750

Factors associated with intensiveness of use of child preventive health services in Taiwan: a comparative study between cross-cultural immigrant families and native-born families.

PubMed

Chien, Su-Chen; Yeh, Yen-Po; Wu, Jyun-Yi; Lin, Chun-Hsiu; Chang, Pei-Chi; Fang, Chiung-Hui; Yang, Hao-Jan

2013-01-01

To compare intensiveness of use of child preventive health services (CPHS) between cross-cultural immigrant families and native-born families in Taiwan and to explore factors associated with differences in intensiveness of CPHS use. Cross-cultural immigrant families were defined as families where the mother was an immigrant from another southeast Asian country. In native-born families, both parents were Taiwanese-born. Data were collected from 318 immigrant mothers and 340 native-born mothers of children aged 7 years or younger in a cross-sectional survey in central Taiwan. A social determinants framework of health inequities was constructed, and ordinal logistic regression models were used to examine the effect of four domains of intermediary determinants on the relationship between family type and underuse of CPHS: CPHS-related factors, medical-related factors, maternal acculturation factors, and sociodemographic/socioeconomic characteristics. Cross-cultural immigrant families were less likely to intensively use CPHS than native-born families. This difference appeared to be mediated by the greater likelihood of having an older child or a lower educated father in cross-cultural families. Findings of this study highlight the importance of promoting health behaviors and combating health inequities and social inequalities for cross-cultural immigrant families in Taiwan from a sociodemographic/socioeconomic and political context.

Generalized anxiety disorder in racial and ethnic minorities: a case of nativity and contextual factors.

PubMed

Budhwani, Henna; Hearld, Kristine Ria; Chavez-Yenter, Daniel

2015-04-01

Minorities comprise more than one third of the U.S., and research on the correlates and causes of depression, anxiety, and other mental illnesses have yielded mixed results in minority groups necessitating an understanding of causes and correlates of health. Thus, the aim of this paper is to evaluate the relationship between minority status, contextual factors, and lifetime Generalized Anxiety Disorder. Logistic regression models were implemented, comparing immigrants to their American-born counterparts as well as to American-born Whites. Foreign-born Afro-Caribbeans exhibited lower rates of lifetime GAD. A lower percentage of foreign-born minorities met the criteria for GAD as compared to their American-born counterparts, and all racial and ethnic groups met the criteria for lifetime GAD at a lower rate as compared to American-born Whites. By using theory proactively and including contextual factors, this multi-faceted approach to health disparities research yielded findings which both supported historic beliefs but created opportunities for supplemental research looking at immigrants and GAD. Key findings were that health lifestyle choices and exposure to discrimination significantly affected the chance of having GAD. Nativity was protective; however, its effect was ameliorated by exposure to discrimination or engagement in alcohol abuse. Thus, this study offers practical insight into environmental factors for clinicians caring for racial and ethnic minorities diagnosed with GAD. Copyright © 2015 Elsevier B.V. All rights reserved.

Hispanic and Immigrant Paradoxes in U.S. Breast Cancer Mortality: Impact of Neighborhood Poverty and Hispanic Density.

PubMed

Pruitt, Sandi L; Tiro, Jasmin A; Xuan, Lei; Lee, Simon J Craddock

2016-12-14

To test the Hispanic and Immigrant Paradoxes-i.e., survival advantages despite a worse risk factor profile-and the modifying role of neighborhood context, we examined associations between patient ethnicity, birthplace, neighborhood Hispanic density and neighborhood poverty among 166,254 female breast cancer patients diagnosed 1995-2009 in Texas, U.S. Of all, 79.9% were non-Hispanic White, 15.8% Hispanic U.S.-born, and 4.2% Hispanic foreign-born. We imputed birthplace for the 60.7% of Hispanics missing birthplace data using multiple imputation. Shared frailty Cox proportional hazard models (patients nested within census tracts) adjusted for age, diagnosis year, stage, grade, histology, urban/rural residence, and local mammography capacity. Whites (vs. U.S.-born Hispanics) had increased all-cause and breast cancer mortality. Foreign-born (vs. U.S.-born) Hispanics had increased all-cause and breast cancer mortality. Living in higher Hispanic density neighborhoods was generally associated with increased mortality, although associations differed slightly in magnitude and significance by ethnicity, birthplace, and neighborhood poverty. We found no evidence of an Immigrant Paradox and some evidence of a Hispanic Paradox where protective effects were limited to U.S.-born Hispanics. Contrary to prior studies, foreign birthplace and residence in higher Hispanic density neighborhoods were associated with increased mortality. More research on intersections between ethnicity, birthplace and neighborhood context are needed.

Predictability of tick-borne encephalitis fluctuations.

PubMed

Zeman, P

2017-10-01

Tick-borne encephalitis is a serious arboviral infection with unstable dynamics and profound inter-annual fluctuations in case numbers. A dependable predictive model has been sought since the discovery of the disease. The present study demonstrates that four superimposed cycles, approximately 2·4, 3, 5·4, and 10·4 years long, can account for three-fifths of the variation in the disease fluctuations over central Europe. Using harmonic regression, these cycles can be projected into the future, yielding forecasts of sufficient accuracy for up to 4 years ahead. For the years 2016-2018, this model predicts elevated incidence levels in most parts of the region.

First-principles calculations reveal controlling principles for carrier mobilities in semiconductors

DOE PAGES

Wu, Yu -Ning; Zhang, Xiaoguang; Pantelides, Sokrates T.; ...

2016-10-11

It has long been believed that carrier mobilities in semiconductors can be calculated by Fermi s golden rule (Born approximation). Phenomenological models for scattering amplitudes are typically used for engineering- level device modeling. Here we introduce a parameter-free, first-principles approach based on complex- wavevector energy bands that does not invoke the Born approximation. We show that phonon-limited mobility is controlled by low-resistivity percolation paths and that in ionized-impurity scattering one must account for the effect of the screening charge, which cancels most of the Coulomb tail.Finally, calculated electron mobilities in silicon are in agreement with experimental data.

Spatial model for transmission of mosquito-borne diseases

NASA Astrophysics Data System (ADS)

Kon, Cynthia Mui Lian; Labadin, Jane

2015-05-01

In this paper, a generic model which takes into account spatial heterogeneity for the dynamics of mosquito-borne diseases is proposed. The dissemination of the disease is described by a system of reaction-diffusion partial differential equations. Host human and vector mosquito populations are divided into susceptible and infectious classes. Diffusion is considered to occur in all classes of both populations. Susceptible humans are infected when bitten by infectious mosquitoes. Susceptible mosquitoes bite infectious humans and become infected. The biting rate of mosquitoes is considered to be density dependent on the total human population in different locations. The system is solved numerically and results are shown.

Modified Eddington-inspired-Born-Infeld gravity with a trace term

DOE PAGES

Chen, Che -Yu; Bouhmadi-Lopez, Mariam; Chen, Pisin

2016-01-22

In this study, a modified Eddington-inspired-Born-Infeld (EiBI) theory with a pure trace term g μνR being added to the determinantal action is analysed from a cosmological point of view. It corresponds to the most general action constructed from a rank two tensor that contains up to first order terms in curvature. This term can equally be seen as a conformal factor multiplying the metric g μν . This very interesting type of amendment has not been considered within the Palatini formalism despite the large amount of works on the Born-Infeld-inspired theory of gravity. This model can provide smooth bouncing solutionsmore » which were not allowed in the EiBI model for the same EiBI coupling. Most interestingly, for a radiation filled universe there are some regions of the parameter space that can naturally lead to a de Sitter inflationary stage without the need of any exotic matter field. Finally, in this model we discover a new type of cosmic “quasi-sudden” singularity, where the cosmic time derivative of the Hubble rate becomes very large but finite at a finite cosmic time.« less

Disease Risk in a Dynamic Environment: The Spread of Tick-Borne Pathogens in Minnesota, USA

PubMed Central

Robinson, Stacie J.; Neitzel, David F.; Moen, Ronald A.; Craft, Meggan E.; Hamilton, Karin E.; Johnson, Lucinda B.; Mulla, David J.; Munderloh, Ulrike G.; Redig, Patrick T.; Smith, Kirk E.; Turner, Clarence L.; Umber, Jamie K.; Pelican, Katharine M.

2015-01-01

As humans and climate change alter the landscape, novel disease risk scenarios emerge. Understanding the complexities of pathogen emergence and subsequent spread as shaped by landscape heterogeneity is crucial to understanding disease emergence, pinpointing high-risk areas, and mitigating emerging disease threats in a dynamic environment. Tick-borne diseases present an important public health concern and incidence of many of these diseases are increasing in the United States. The complex epidemiology of tick-borne diseases includes strong ties with environmental factors that influence host availability, vector abundance, and pathogen transmission. Here, we used 16 years of case data from the Minnesota Department of Health to report spatial and temporal trends in Lyme disease (LD), human anaplasmosis, and babesiosis. We then used a spatial regression framework to evaluate the impact of landscape and climate factors on the spread of LD. Finally, we use the fitted model, and landscape and climate datasets projected under varying climate change scenarios, to predict future changes in tick-borne pathogen risk. Both forested habitat and temperature were important drivers of LD spread in Minnesota. Dramatic changes in future temperature regimes and forest communities predict rising risk of tick-borne disease. PMID:25281302

Surveillance of Arthropod Vector-Borne Infectious Diseases Using Remote Sensing Techniques: A Review

PubMed Central

Kalluri, Satya; Gilruth, Peter; Rogers, David; Szczur, Martha

2007-01-01

Epidemiologists are adopting new remote sensing techniques to study a variety of vector-borne diseases. Associations between satellite-derived environmental variables such as temperature, humidity, and land cover type and vector density are used to identify and characterize vector habitats. The convergence of factors such as the availability of multi-temporal satellite data and georeferenced epidemiological data, collaboration between remote sensing scientists and biologists, and the availability of sophisticated, statistical geographic information system and image processing algorithms in a desktop environment creates a fertile research environment. The use of remote sensing techniques to map vector-borne diseases has evolved significantly over the past 25 years. In this paper, we review the status of remote sensing studies of arthropod vector-borne diseases due to mosquitoes, ticks, blackflies, tsetse flies, and sandflies, which are responsible for the majority of vector-borne diseases in the world. Examples of simple image classification techniques that associate land use and land cover types with vector habitats, as well as complex statistical models that link satellite-derived multi-temporal meteorological observations with vector biology and abundance, are discussed here. Future improvements in remote sensing applications in epidemiology are also discussed. PMID:17967056

Health and Development of Children Born after Assisted Reproductive Technology and Sub-Fertility Compared to Naturally Conceived Children: Data from a National Study

PubMed Central

Sutcliffe, Alastair G.; Melhuish, Edward; Barnes, Jacqueline; Gardiner, Julian

2014-01-01

In a non-matched case-control study using data from two large national cohort studies, we investigated whether indicators of child health and development up to 7 years of age differ between children conceived using assisted reproductive technology (ART), children born after sub-fertility (more than 24 months of trying for conception) and other children. Information on ART use/sub-fertility was available for 23,649 children. There were 227 cases (children conceived through ART) and two control groups: 783 children born to sub-fertile couples, and 22,639 children born to couples with no fertility issues. In models adjusted for social and demographic factors there were significant differences between groups in rate of hospital admissions before the children were 9 months old (P=0.029), with the ART group showing higher rates of hospital admission than the no fertility issues control group, the sub-fertile control group being intermediate between the two. Children born after ART had comparable health and development beyond 9 months of age to their naturally conceived peers. This applied to the whole sample and to a sub-sample of children from deprived neighborhoods. PMID:24711911

The Influence of Hispanic Ethnicity and Nativity Status on 2009 H1N1 Pandemic Vaccination Uptake in the United States.

PubMed

Burger, Andrew E; Reither, Eric N; Hofmann, Erin Trouth; Mamelund, Svenn-Erik

2018-06-01

Previous research suggests Hispanic vaccination rates for H1N1 were similar to non-Hispanic whites. These previous estimates do not take into account nativity status. Using the 2010 National Health Interview Survey, we estimate adult H1N1 vaccination rates for non-Hispanic whites (n = 8780), U.S.-born Hispanics (n = 1142), and foreign-born Hispanics (n = 1912). To test Fundamental Cause Theory, we estimate odds of H1N1 vaccination while controlling for flexible resources (e.g., educational and economic capital), ethnicity, and nativity status. Foreign-born Hispanics experienced the lowest rates of H1N1 vaccination (15%), followed by U.S.-born Hispanics (18%) and non-Hispanic whites (21%). Regression models show odds of H1N1 vaccination did not differ among these three groups after controlling for sociodemographic characteristics. Insufficient access to flexible resources and healthcare coverage among foreign-born Hispanics was responsible for relatively low rates of H1N1 vaccination. Addressing resource disparities among Hispanics could increase vaccination uptake in the future, reducing inequities in disease burden.

Disease risk in a dynamic environment: the spread of tick-borne pathogens in Minnesota, USA.

PubMed

Robinson, Stacie J; Neitzel, David F; Moen, Ronald A; Craft, Meggan E; Hamilton, Karin E; Johnson, Lucinda B; Mulla, David J; Munderloh, Ulrike G; Redig, Patrick T; Smith, Kirk E; Turner, Clarence L; Umber, Jamie K; Pelican, Katharine M

2015-03-01

As humans and climate change alter the landscape, novel disease risk scenarios emerge. Understanding the complexities of pathogen emergence and subsequent spread as shaped by landscape heterogeneity is crucial to understanding disease emergence, pinpointing high-risk areas, and mitigating emerging disease threats in a dynamic environment. Tick-borne diseases present an important public health concern and incidence of many of these diseases are increasing in the United States. The complex epidemiology of tick-borne diseases includes strong ties with environmental factors that influence host availability, vector abundance, and pathogen transmission. Here, we used 16 years of case data from the Minnesota Department of Health to report spatial and temporal trends in Lyme disease (LD), human anaplasmosis, and babesiosis. We then used a spatial regression framework to evaluate the impact of landscape and climate factors on the spread of LD. Finally, we use the fitted model, and landscape and climate datasets projected under varying climate change scenarios, to predict future changes in tick-borne pathogen risk. Both forested habitat and temperature were important drivers of LD spread in Minnesota. Dramatic changes in future temperature regimes and forest communities predict rising risk of tick-borne disease.

Integrated vector management: a critical strategy for combating vector-borne diseases in South Sudan.

PubMed

Chanda, Emmanuel; Govere, John M; Macdonald, Michael B; Lako, Richard L; Haque, Ubydul; Baba, Samson P; Mnzava, Abraham

2013-10-25

Integrated vector management (IVM) based vector control is encouraged by the World Health Organization (WHO). However, operational experience with the IVM strategy has mostly come from countries with relatively well-established health systems and with malaria control focused programmes. Little is known about deployment of IVM for combating multiple vector-borne diseases in post-emergency settings, where delivery structures are less developed or absent. This manuscript reports on the feasibility of operational IVM for combating vector-borne diseases in South Sudan. A methodical review of published and unpublished documents on vector-borne diseases for South Sudan was conducted via systematic literature search of online electronic databases, Google Scholar, PubMed and WHO, using a combination of search terms. Additional, non-peer reviewed literature was examined for information related to the subject. South Sudan is among the heartlands of vector-borne diseases in the world, characterized by enormous infrastructure, human and financial resource constraints and a weak health system against an increasing number of refugees, returnees and internally displaced people. The presence of a multiplicity of vector-borne diseases in this post-conflict situation presents a unique opportunity to explore the potential of a rational IVM strategy for multiple disease control and optimize limited resource utilization, while maximizing the benefits and providing a model for countries in a similar situation. The potential of integrating vector-borne disease control is enormous in South Sudan. However, strengthened coordination, intersectoral collaboration and institutional and technical capacity for entomological monitoring and evaluation, including enforcement of appropriate legislation are crucial.

Integrated vector management: a critical strategy for combating vector-borne diseases in South Sudan

PubMed Central

2013-01-01

Background Integrated vector management (IVM) based vector control is encouraged by the World Health Organization (WHO). However, operational experience with the IVM strategy has mostly come from countries with relatively well-established health systems and with malaria control focused programmes. Little is known about deployment of IVM for combating multiple vector-borne diseases in post-emergency settings, where delivery structures are less developed or absent. This manuscript reports on the feasibility of operational IVM for combating vector-borne diseases in South Sudan. Case description A methodical review of published and unpublished documents on vector-borne diseases for South Sudan was conducted via systematic literature search of online electronic databases, Google Scholar, PubMed and WHO, using a combination of search terms. Additional, non-peer reviewed literature was examined for information related to the subject. Discussion South Sudan is among the heartlands of vector-borne diseases in the world, characterized by enormous infrastructure, human and financial resource constraints and a weak health system against an increasing number of refugees, returnees and internally displaced people. The presence of a multiplicity of vector-borne diseases in this post-conflict situation presents a unique opportunity to explore the potential of a rational IVM strategy for multiple disease control and optimize limited resource utilization, while maximizing the benefits and providing a model for countries in a similar situation. Conclusion The potential of integrating vector-borne disease control is enormous in South Sudan. However, strengthened coordination, intersectoral collaboration and institutional and technical capacity for entomological monitoring and evaluation, including enforcement of appropriate legislation are crucial. PMID:24156749

Understanding the effect of vector dynamics in epidemic models using center manifold analysis

NASA Astrophysics Data System (ADS)

Rocha, Filipe; Aguiar, Maíra; Souza, Max; Stollenwerk, Nico

2012-09-01

In vector borne diseases the human hosts' epidemiology often acts on a much slower time scales than the one of the mosquitos which transmit the disease as a vector from human to human, due to their vastly different life cycles. We investigate in a model with susceptible (S), infected (I) and recovered (R) humans and susceptible (U) and infected (V) mosquitoes in how far the fast time scale of the mosquito epidemiology can be slaved by the slower human epidemiology, so that for the understanding of human disease data mainly the dynamics of the human time scale is essential and only slightly perturbed by the mosquito dynamics. This analysis of the SIRUV model is qualitatively in agreement with a previously investigated simpler SISUV model, hence a feature of vector-borne diseases in general.

Essays in energy economics: The electricity industry

NASA Astrophysics Data System (ADS)

Martinez-Chombo, Eduardo

Electricity demand analysis using cointegration and error-correction models with time varying parameters: The Mexican case. In this essay we show how some flexibility can be allowed in modeling the parameters of the electricity demand function by employing the time varying coefficient (TVC) cointegrating model developed by Park and Hahn (1999). With the income elasticity of electricity demand modeled as a TVC, we perform tests to examine the adequacy of the proposed model against the cointegrating regression with fixed coefficients, as well as against the spuriousness of the regression with TVC. The results reject the specification of the model with fixed coefficients and favor the proposed model. We also show how some flexibility is gained in the specification of the error correction model based on the proposed TVC cointegrating model, by including more lags of the error correction term as predetermined variables. Finally, we present the results of some out-of-sample forecast comparison among competing models. Electricity demand and supply in Mexico. In this essay we present a simplified model of the Mexican electricity transmission network. We use the model to approximate the marginal cost of supplying electricity to consumers in different locations and at different times of the year. We examine how costs and system operations will be affected by proposed investments in generation and transmission capacity given a forecast of growth in regional electricity demands. Decomposing electricity prices with jumps. In this essay we propose a model that decomposes electricity prices into two independent stochastic processes: one that represents the "normal" pattern of electricity prices and the other that captures temporary shocks, or "jumps", with non-lasting effects in the market. Each contains specific mean reverting parameters to estimate. In order to identify such components we specify a state-space model with regime switching. Using Kim's (1994) filtering algorithm we estimate the parameters of the model, the transition probabilities and the unobservable components for the mean adjusted series of New South Wales' electricity prices. Finally, bootstrap simulations were performed to estimate the expected contribution of each of the components in the overall electricity prices.

Electrical utilities model for determining electrical distribution capacity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fritz, R. L.

1997-09-03

In its simplest form, this model was to obtain meaningful data on the current state of the Site`s electrical transmission and distribution assets, and turn this vast collection of data into useful information. The resulting product is an Electrical Utilities Model for Determining Electrical Distribution Capacity which provides: current state of the electrical transmission and distribution systems; critical Hanford Site needs based on outyear planning documents; decision factor model. This model will enable Electrical Utilities management to improve forecasting requirements for service levels, budget, schedule, scope, and staffing, and recommend the best path forward to satisfy customer demands at themore » minimum risk and least cost to the government. A dynamic document, the model will be updated annually to reflect changes in Hanford Site activities.« less

Modeling Instruction in AP Physics C: Mechanics and Electricity and Magnetism

NASA Astrophysics Data System (ADS)

Belcher, Nathan Tillman

This action research study used data from multiple assessments in Mechanics and Electricity and Magnetism to determine the viability of Modeling Instruction as a pedagogy for students in AP Physics C: Mechanics and Electricity and Magnetism. Modeling Instruction is a guided-inquiry approach to teaching science in which students progress through the Modeling Cycle to develop a fully-constructed model for a scientific concept. AP Physics C: Mechanics and Electricity and Magnetism are calculus-based physics courses, approximately equivalent to first-year calculus-based physics courses at the collegiate level. Using a one-group pretest-posttest design, students were assessed in Mechanics using the Force Concept Inventory, Mechanics Baseline Test, and 2015 AP Physics C: Mechanics Practice Exam. With the same design, students were assessed in Electricity and Magnetism on the Brief Electricity and Magnetism Assessment, Electricity and Magnetism Conceptual Assessment, and 2015 AP Physics C: Electricity and Magnetism Practice Exam. In a one-shot case study design, student scores were collected from the 2017 AP Physics C: Mechanics and Electricity and Magnetism Exams. Students performed moderately well on the assessments in Mechanics and Electricity and Magnetism, demonstrating that Modeling Instruction is a viable pedagogy in AP Physics C: Electricity and Magnetism.

Short-Term Energy Outlook Model Documentation: Electricity Generation and Fuel Consumption Models

EIA Publications

2014-01-01

The electricity generation and fuel consumption models of the Short-Term Energy Outlook (STEO) model provide forecasts of electricity generation from various types of energy sources and forecasts of the quantities of fossil fuels consumed for power generation. The structure of the electricity industry and the behavior of power generators varies between different areas of the United States. In order to capture these differences, the STEO electricity supply and fuel consumption models are designed to provide forecasts for the four primary Census regions.

On gravitational waves in Born-Infeld inspired non-singular cosmologies

NASA Astrophysics Data System (ADS)

Beltrán Jiménez, Jose; Heisenberg, Lavinia; Olmo, Gonzalo J.; Rubiera-Garcia, Diego

2017-10-01

We study the evolution of gravitational waves for non-singular cosmological solutions within the framework of Born-Infeld inspired gravity theories, with special emphasis on the Eddington-inspired Born-Infeld theory. We review the existence of two types of non-singular cosmologies, namely bouncing and asymptotically Minkowski solutions, from a perspective that makes their features more apparent. We study in detail the propagation of gravitational waves near these non-singular solutions and carefully discuss the origin and severity of the instabilities and strong coupling problems that appear. We also investigate the role of the adiabatic sound speed of the matter sector in the regularisation of the gravitational waves evolution. We extend our analysis to more general Born-Infeld inspired theories where analogous solutions are found. As a general conclusion, we obtain that the bouncing solutions are generally more prone to instabilities, while the asymptotically Minkowski solutions can be rendered stable, making them appealing models for the early universe.

Fusion of SAR and Optical Imagery for Studying the Eco-Epidemiology of Vector-Borne Diseases in Tropical Countries

NASA Astrophysics Data System (ADS)

Catry, Thibault; Li, Zhichao; Roux, Emmanuel; Herreteau, Vincent; Revillion, Christophe; Dessay, Nadine

2016-08-01

Vector-borne diseases like malaria represent a major public health issue worldwide. Other mosquito-borne diseases affect more and more countries and people, with effects on health which are not all identified yet. Recent developments in the field of remote-sensing allow to consider overriding the existing limits of studying such diseases in tropical regions, where cloud and vegetation cover often prevent to identify and characterize environmental features.We highlight the potential of SAR-optical fusion for the mapping of land cover, the identification of wetlands, and the monitoring of environmental changes in different habitats related to vector-borne diseases in the French Guiana - Brazil cross-border area. This study is the foundation of a landscape-based model of malaria transmission risk. Environmental factors, together with epidemiological, socio-economic, behavioral, demographics, and entomological ones, contribute to assess risks related to such pathologies and support disease control and decision-making by local public health actors.

On gravitational waves in Born-Infeld inspired non-singular cosmologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiménez, Jose Beltrán; Heisenberg, Lavinia; Olmo, Gonzalo J.

We study the evolution of gravitational waves for non-singular cosmological solutions within the framework of Born-Infeld inspired gravity theories, with special emphasis on the Eddington-inspired Born-Infeld theory. We review the existence of two types of non-singular cosmologies, namely bouncing and asymptotically Minkowski solutions, from a perspective that makes their features more apparent. We study in detail the propagation of gravitational waves near these non-singular solutions and carefully discuss the origin and severity of the instabilities and strong coupling problems that appear. We also investigate the role of the adiabatic sound speed of the matter sector in the regularisation of themore » gravitational waves evolution. We extend our analysis to more general Born-Infeld inspired theories where analogous solutions are found. As a general conclusion, we obtain that the bouncing solutions are generally more prone to instabilities, while the asymptotically Minkowski solutions can be rendered stable, making them appealing models for the early universe.« less

The perfect food and the filth disease: milk-borne typhoid and epidemiological practice in late Victorian Britain.

PubMed

Steere-Williams, Jacob

2010-10-01

This article explores the initial set of epidemiological investigations in Victorian Britain that linked typhoid fever to milk from dairy cattle. Because Victorian epidemiologists first recognized the milk-borne route in outbreaks of typhoid fever, these investigations served as a model for later studies of milk-borne scarlet fever, diphtheria, and perhaps tuberculosis. By focusing on epidemiological practices conducted by Medical Inspectors at the Medical Department of the Local Government Board and Medical Officers of Health, I show that Victorian epidemiology was committed to field-based, observational methods that defined the professional nature of the discipline and its theories and practices. Epidemiological investigations of milk-borne typhoid heated up several important public health debates in the second half of the nineteenth century, and demonstrate how Victorian epidemiology was not solely wedded to examining population studies using statistical methods, as historians have typically argued, but also relied on observational case-tracing in individuals, animals, and even environments.

Short-term electric power demand forecasting based on economic-electricity transmission model

NASA Astrophysics Data System (ADS)

Li, Wenfeng; Bai, Hongkun; Liu, Wei; Liu, Yongmin; Wang, Yubin Mao; Wang, Jiangbo; He, Dandan

2018-04-01

Short-term electricity demand forecasting is the basic work to ensure safe operation of the power system. In this paper, a practical economic electricity transmission model (EETM) is built. With the intelligent adaptive modeling capabilities of Prognoz Platform 7.2, the econometric model consists of three industrial added value and income levels is firstly built, the electricity demand transmission model is also built. By multiple regression, moving averages and seasonal decomposition, the problem of multiple correlations between variables is effectively overcome in EETM. The validity of EETM is proved by comparison with the actual value of Henan Province. Finally, EETM model is used to forecast the electricity consumption of the 1-4 quarter of 2018.

Medium-term electric power demand forecasting based on economic-electricity transmission model

NASA Astrophysics Data System (ADS)

Li, Wenfeng; Bao, Fangmin; Bai, Hongkun; Liu, Wei; Liu, Yongmin; Mao, Yubin; Wang, Jiangbo; Liu, Junhui

2018-06-01

Electric demand forecasting is a basic work to ensure the safe operation of power system. Based on the theories of experimental economics and econometrics, this paper introduces Prognoz Platform 7.2 intelligent adaptive modeling platform, and constructs the economic electricity transmission model that considers the economic development scenarios and the dynamic adjustment of industrial structure to predict the region's annual electricity demand, and the accurate prediction of the whole society's electricity consumption is realized. Firstly, based on the theories of experimental economics and econometrics, this dissertation attempts to find the economic indicator variables that drive the most economical growth of electricity consumption and availability, and build an annual regional macroeconomic forecast model that takes into account the dynamic adjustment of industrial structure. Secondly, it innovatively put forward the economic electricity directed conduction theory and constructed the economic power transfer function to realize the group forecast of the primary industry + rural residents living electricity consumption, urban residents living electricity, the second industry electricity consumption, the tertiary industry electricity consumption; By comparing with the actual value of economy and electricity in Henan province in 2016, the validity of EETM model is proved, and the electricity consumption of the whole province from 2017 to 2018 is predicted finally.

An Undergraduate Student Instrumentation Project (USIP) to Develop New Instrument Technology to Study the Auroral Ionosphere and Stratospheric Ozone Layer Using Ultralight Balloon Payloads

NASA Astrophysics Data System (ADS)

Gamblin, R.; Marrero, E.; Bering, E. A., III; Leffer, B.; Dunbar, B.; Ahmad, H.; Canales, D.; Bias, C.; Cao, J.; Pina, M.; Ehteshami, A.; Hermosillo, D.; Siddiqui, A.; Guala, D.

2014-12-01

This project is currently engaging tweleve undergraduate students in the process of developing new technology and instrumentation for use in balloon borne geospace investigations in the auroral zone. Motivation stems from advances in microelectronics and consumer electronic technology. Given the technological inovations over the past 20 years it now possible to develop new instrumentation to study the auroral ionosphere and stratospheric ozone layer using ultralight balloon payloads for less than 6lbs and $3K per payload. The UH USIP undergraduate team is currently in the process of build ten such payloads for launch using1500 gm latex weather balloons to be deployed in Houston and Fairbanks, AK as well as zero pressure balloons launched from northern Sweden. The latex balloon project will collect vertical profiles of wind speed, wind direction, temperature, electrical conductivity, ozone and odd nitrogen. This instrument payload will also profiles of pressure, electric field, and air-earth electric current. The zero pressure balloons will obtain a suite of geophysical measurements including: DC electric field, electric field and magnetic flux, optical imaging, total electron content of ionosphere via dual-channel GPS, X-ray detection, and infrared/UV spectroscopy. Students will fly payloads with different combinations of these instruments to determine which packages are successful. Data collected by these instruments will be useful in understanding the nature of electrodynamic coupling in the upper atmosphere and how the global earth system is changing. Results and best practices learned from lab tests and initial Houston test flights will be discussed.

History of electromyography and nerve conduction studies: A tribute to the founding fathers.

PubMed

Kazamel, Mohamed; Warren, Paula Province

2017-09-01

The early development of nerve conduction studies (NCS) and electromyography (EMG) was linked to the discovery of electricity. This relationship had been concluded by observing the effect of applying electricity to the body of an animal and discovering that nerves and muscles themselves could produce electricity. We attempt to review the historical evolution of NCS and EMG over the last three centuries by reviewing the landmark publications of Galvani, Adrian, Denny-Brown, Larrabee, and Lambert. In 1771, Galvani showed that electrical stimulation of animal muscle tissue produced contraction and, thereby, the concept of animal electricity was born. In 1929, Adrian devised a method to record a single motor unit potential by connecting concentric needle electrodes to an amplifier and a loud speaker. In 1938, Denny-Brown described the fasciculation potentials and separated them from fibrillations. Toward the end of World War II, Larrabee began measuring the compound muscle action potential in healthy and injured nerves of war victims. In 1957, Lambert and Eaton described the electrophysiologic features of a new myasthenic syndrome associated with lung carcinoma. Overall, research on this topic was previously undertaken by neurophysiologists and then later by neurologists, with Adrian most likely being the first neurologist to be involved. The field greatly benefited from the invention of equipment that was capable of amplifying small bioelectrical currents by the beginning of the 20th century. Significant scientific and technical advances were later made during and after World War II which provided a large patient population with nerve injuries to study. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multigrid based First-Principles Molecular Dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fattebert, Jean-Luc; Osei-Kuffuor, Daniel; Dunn, Ian

2017-06-01

MGmol ls a First-Principles Molecular Dynamics code. It relies on the Born-Oppenheimer approximation and models the electronic structure using Density Functional Theory, either LDA or PBE. Norm-conserving pseudopotentials are used to model atomic cores.

Nephron Deficiency and Predisposition to Renal Injury in a Novel One-Kidney Genetic Model

PubMed Central

Wang, Xuexiang; Johnson, Ashley C.; Williams, Jan M.; White, Tiffani; Chade, Alejandro R.; Zhang, Jie; Liu, Ruisheng; Roman, Richard J.; Lee, Jonathan W.; Kyle, Patrick B.; Solberg-Woods, Leah

2015-01-01

Some studies have reported up to 40% of patients born with a single kidney develop hypertension, proteinuria, and in some cases renal failure. The increased susceptibility to renal injury may be due, in part, to reduced nephron numbers. Notably, children who undergo nephrectomy or adults who serve as kidney donors exhibit little difference in renal function compared with persons who have two kidneys. However, the difference in risk between being born with a single kidney versus being born with two kidneys and then undergoing nephrectomy are unclear. Animal models used previously to investigate this question are not ideal because they require invasive methods to model congenital solitary kidney. In this study, we describe a new genetic animal model, the heterogeneous stock-derived model of unilateral renal agenesis (HSRA) rat, which demonstrates 50%–75% spontaneous incidence of a single kidney. The HSRA model is characterized by reduced nephron number (more than would be expected by loss of one kidney), early kidney/glomerular hypertrophy, and progressive renal injury, which culminates in reduced renal function. Long-term studies of temporal relationships among BP, renal hemodynamics, and renal function demonstrate that spontaneous single-kidney HSRA rats are more likely than uninephrectomized normal littermates to exhibit renal impairment because of the combination of reduced nephron numbers and prolonged exposure to renal compensatory mechanisms (i.e., hyperfiltration). Future studies with this novel animal model may provide additional insight into the genetic contributions to kidney development and agenesis and the factors influencing susceptibility to renal injury in individuals with congenital solitary kidney. PMID:25349207

Nephron Deficiency and Predisposition to Renal Injury in a Novel One-Kidney Genetic Model.

PubMed

Wang, Xuexiang; Johnson, Ashley C; Williams, Jan M; White, Tiffani; Chade, Alejandro R; Zhang, Jie; Liu, Ruisheng; Roman, Richard J; Lee, Jonathan W; Kyle, Patrick B; Solberg-Woods, Leah; Garrett, Michael R

2015-07-01

Some studies have reported up to 40% of patients born with a single kidney develop hypertension, proteinuria, and in some cases renal failure. The increased susceptibility to renal injury may be due, in part, to reduced nephron numbers. Notably, children who undergo nephrectomy or adults who serve as kidney donors exhibit little difference in renal function compared with persons who have two kidneys. However, the difference in risk between being born with a single kidney versus being born with two kidneys and then undergoing nephrectomy are unclear. Animal models used previously to investigate this question are not ideal because they require invasive methods to model congenital solitary kidney. In this study, we describe a new genetic animal model, the heterogeneous stock-derived model of unilateral renal agenesis (HSRA) rat, which demonstrates 50%-75% spontaneous incidence of a single kidney. The HSRA model is characterized by reduced nephron number (more than would be expected by loss of one kidney), early kidney/glomerular hypertrophy, and progressive renal injury, which culminates in reduced renal function. Long-term studies of temporal relationships among BP, renal hemodynamics, and renal function demonstrate that spontaneous single-kidney HSRA rats are more likely than uninephrectomized normal littermates to exhibit renal impairment because of the combination of reduced nephron numbers and prolonged exposure to renal compensatory mechanisms (i.e., hyperfiltration). Future studies with this novel animal model may provide additional insight into the genetic contributions to kidney development and agenesis and the factors influencing susceptibility to renal injury in individuals with congenital solitary kidney. Copyright © 2015 by the American Society of Nephrology.

Climate Change, Public Health, and Decision Support: The New Threat of Vector-borne Disease

NASA Astrophysics Data System (ADS)

Grant, F.; Kumar, S.

2011-12-01

Climate change and vector-borne diseases constitute a massive threat to human development. It will not be enough to cut emissions of greenhouse gases-the tide of the future has already been established. Climate change and vector-borne diseases are already undermining the world's efforts to reduce extreme poverty. It is in the best interests of the world leaders to think in terms of concerted global actions, but adaptation and mitigation must be accomplished within the context of local community conditions, resources, and needs. Failure to act will continue to consign developed countries to completely avoidable health risks and significant expense. Failure to act will also reduce poorest of the world's population-some 2.6 billion people-to a future of diminished opportunity. Northrop Grumman has taken significant steps forward to develop the tools needed to assess climate change impacts on public health, collect relevant data for decision making, model projections at regional and local levels; and, deliver information and knowledge to local and regional stakeholders. Supporting these tools is an advanced enterprise architecture consisting of high performance computing, GIS visualization, and standards-based architecture. To address current deficiencies in local planning and decision making with respect to regional climate change and its effect on human health, our research is focused on performing a dynamical downscaling with the Weather Research and Forecasting (WRF) model to develop decision aids that translate the regional climate data into actionable information for users. For the present climate WRF was forced with the Max Planck Institute European Center/Hamburg Model version 5 (ECHAM5) General Circulation Model 20th century simulation. For the 21th century climate, we used an ECHAM5 simulation with the Special Report on Emissions (SRES) A1B emissions scenario. WRF was run in nested mode at spatial resolution of 108 km, 36 km and 12 km and 28 vertical levels. This model was examined relative to two mosquito vectors, both competent carriers of dengue fever, a viral, vector-borne disease. Models which incorporate public health considerations can enable decision makers to take proactive steps to mitigate the impacts and adapt to the changing environmental conditions. In this paper we provide a snapshot of our climate initiative and some examples relative to our public health practice work in vector-borne diseases to illustrate how integrated decision support could be of assistance to regional and local communities worldwide.

Modeling Mosquito-Borne Disease Spread in U.S. Urbanized Areas: The Case of Dengue in Miami

PubMed Central

Robert, Michael A.; Christofferson, Rebecca C.; Silva, Noah J. B.; Vasquez, Chalmers; Mores, Christopher N.; Wearing, Helen J.

2016-01-01

Expansion of mosquito-borne pathogens into more temperate regions of the world necessitates tools such as mathematical models for understanding the factors that contribute to the introduction and emergence of a disease in populations naïve to the disease. Often, these models are not developed and analyzed until after a pathogen is detected in a population. In this study, we develop a spatially explicit stochastic model parameterized with publicly available U.S. Census data for studying the potential for disease spread in Urbanized Areas of the United States. To illustrate the utility of the model, we specifically study the potential for introductions of dengue to lead to autochthonous transmission and outbreaks in a population representative of the Miami Urbanized Area, where introductions of dengue have occurred frequently in recent years. We describe seasonal fluctuations in mosquito populations by fitting a population model to trap data provided by the Miami-Dade Mosquito Control Division. We show that the timing and location of introduced cases could play an important role in determining both the probability that local transmission occurs as well as the total number of cases throughout the entire region following introduction. We show that at low rates of clinical presentation, small outbreaks of dengue could go completely undetected during a season, which may confound mitigation efforts that rely upon detection. We discuss the sensitivity of the model to several critical parameter values that are currently poorly characterized and motivate the collection of additional data to strengthen the predictive power of this and similar models. Finally, we emphasize the utility of the general structure of this model in studying mosquito-borne diseases such as chikungunya and Zika virus in other regions. PMID:27532496

Balloon Borne Instrumentation for Detection of Gamma Ray Glows

NASA Astrophysics Data System (ADS)

Sterpka, C. F.; Bagheri, M.; Dwyer, J. R.; Liu, N.; Morman, K.; Gadbois, J. L.; Bozarth, A.; Boggs, L.; Mailyan, B. G.; Nag, A.; Lazarus, S. M.; Austin, M.; Aguirre, F.; Colvin, J.; Haley, V.; Rassoul, H.

2017-12-01

Gamma-ray glows are emissions of gamma rays that last from seconds to minutes and are produced by runaway electrons in high-field regions of thunderclouds. The lightning group at the University of New Hampshire in collaboration with the Florida Institute of Technology has designed balloon-based instrumentation for flying into thunderstorms with the aim of detecting such radiation. The instrumentation includes two Geiger-Muller tubes, sensitive to both gamma rays and charged particles, and a low-power lightweight electric field mill, designed and calibrated to measure both polarity and amplitude of the vertical electric field inside the thunderstorm region. With the polarity measurement provided by the field mill, the Geiger-Muller tubes should be capable of differentiating energetic electrons from positrons. Additionally, a lead sheet is placed between the Geiger-Muller tubes to differentiate between charged particles and gamma rays. We have conducted several test flights of this system during the summer of 2017. In this study, we will present an overview of the instrumentation and discuss preliminary results from the test flights.

Middle atmosphere measurements of small-scale electron density irregularities and ion properties during the MAC/Epsilon campaign

NASA Technical Reports Server (NTRS)

Blood, S. P.; Mitchell, J. D.; Croskey, C. L.

1989-01-01

Rocket payloads designed to measure small scale electron density irregularities and ion properties in the middle atmosphere were flown with each of the three main salvos of the MAC/Epsilon campaign conducted at the Andoya Rocket Range, Norway, during October to November 1987. Fixed bias, hemispheric nose tip probes measured small scale electron density irregularities, indicative of neutral air turbulence, during the rocket's ascent; and subsequently, parachute-borne Gerdien condensers measured the region's polar electrical conductivity, ion mobility and density. One rocket was launched during daylight (October 15, 1052:20 UT), and the other two launches occurred at night (October 21, 2134 UT: November 12, 0021:40 UT) under moderately disturbed conditions which enhanced the detection and measurement of turbulence structures. A preliminary analysis of the real time data displays indicates the presence of small scale electron density irregularities in the altitude range of 60 to 90 km. Ongoing data reduction will determine turbulence parameters and also the region's electrical properties below 90 km.

The influence of acculturation on breast-feeding initiation and duration in low-income women in the US.

PubMed

Sussner, Katarina M; Lindsay, Ana C; Peterson, Karen E

2008-09-01

While the 'immigrant health paradox' posits better health behaviours and outcomes for immigrants upon arrival to the US, research suggests that this advantage may deteriorate over time. This study analysed the relationship of acculturation and breast-feeding initiation and duration among a sample of predominantly Latina, low-income women in the US. The four measures of acculturation included: mother's nativity (foreign born vs US born), mother's parents' nativity (foreign born vs US born), years of US residence (<8 years vs > or =8 years) and a dichotomous measure of language acculturation adapted from three items on Marin's acculturation scale (preferred language spoken at home, reading language and writing language) as exclusive use of native language versus non-exclusive use (mixed or English only) (Marin et al., 1987; Marin & Gamba, 1996). Final multivariable models showed that mothers who exclusively used their native language were more likely to initiate breast-feeding as well as breast-feed for longer duration compared with mothers with non-exclusive use, whereas years of US residence and mother's nativity were not significantly associated with breast-feeding initiation or duration. Mother's parents' nativity also emerged as a significant predictor of breast-feeding duration, both within final models for immigrants and across study participants. Programmes providing nutrition education to low-income women may wish to consider the role of language as an important determinant of breast-feeding. The role of mother's parents' nativity on breast-feeding practices deserves exploration in future studies, as the cultural practices taught by family members born outside the US may exert strong pressure within immigrant families now living in the US.

Spatially explicit multi-criteria decision analysis for managing vector-borne diseases

PubMed Central

2011-01-01

The complex epidemiology of vector-borne diseases creates significant challenges in the design and delivery of prevention and control strategies, especially in light of rapid social and environmental changes. Spatial models for predicting disease risk based on environmental factors such as climate and landscape have been developed for a number of important vector-borne diseases. The resulting risk maps have proven value for highlighting areas for targeting public health programs. However, these methods generally only offer technical information on the spatial distribution of disease risk itself, which may be incomplete for making decisions in a complex situation. In prioritizing surveillance and intervention strategies, decision-makers often also need to consider spatially explicit information on other important dimensions, such as the regional specificity of public acceptance, population vulnerability, resource availability, intervention effectiveness, and land use. There is a need for a unified strategy for supporting public health decision making that integrates available data for assessing spatially explicit disease risk, with other criteria, to implement effective prevention and control strategies. Multi-criteria decision analysis (MCDA) is a decision support tool that allows for the consideration of diverse quantitative and qualitative criteria using both data-driven and qualitative indicators for evaluating alternative strategies with transparency and stakeholder participation. Here we propose a MCDA-based approach to the development of geospatial models and spatially explicit decision support tools for the management of vector-borne diseases. We describe the conceptual framework that MCDA offers as well as technical considerations, approaches to implementation and expected outcomes. We conclude that MCDA is a powerful tool that offers tremendous potential for use in public health decision-making in general and vector-borne disease management in particular. PMID:22206355

Antibiotic Utilization and the Role of Suspected and Diagnosed Mosquito-borne Illness Among Adults and Children With Acute Febrile Illness in Pune, India.

PubMed

Robinson, Matthew L; Kadam, Dileep; Kagal, Anju; Khadse, Sandhya; Kinikar, Aarti; Valvi, Chhaya; Basavaraj, Anita; Bharadwaj, Renu; Marbaniang, Ivan; Kanade, Savita; Raichur, Priyanka; Sachs, Jonathan; Klein, Eili; Cosgrove, Sara; Gupta, Amita; Mave, Vidya

2018-05-02

Antibiotic resistance mechanisms originating in low- and middle- income countries are among the most common worldwide. Reducing unnecessary antibiotic use in India, the world's largest antibiotic consumer, is crucial to control antimicrobial resistance globally. Limited data describing factors influencing Indian clinicians to start or stop antibiotics are available. Febrile adults and children admitted to a public tertiary care hospital in Pune, India, were enrolled. Antibiotic usage and clinical history were recorded. Immunoassays for mosquito-borne disease and bacterial cultures were performed by protocol and clinician-directed testing. Clinical factors were assessed for association with empiric antibiotic initiation and discontinuation by day 5 using multivariable logistic regression and propensity score-matched Cox proportional hazard models. Among 1486 participants, 683 (82%) adults and 614 (94%) children received empiric antibiotics. Participants suspected of having mosquito-borne disease were less likely to receive empiric antibiotics (adjusted odds ratio [AOR], 0.5; 95% confidence interval [CI], .4-.8). Empiric antibiotics were discontinued in 450 (35%) participants by day 5. Dengue or malaria testing performed before day 4 was positive in 162 (12%) participants, and was associated with antibiotic discontinuation (AOR, 1.7; 95% CI, 1.2-2.4). In a propensity score-matched model accounting for admission suspicion of mosquito-borne disease, positive dengue or malaria tests increased hazard of antibiotic discontinuation (hazard ratio, 1.6; 95% CI, 1.2-2.0). Most patients with acute febrile illness in an Indian public hospital setting receive empiric antibiotics. Mosquito-borne disease identification is associated with reduced empiric antibiotic use and faster antibiotic discontinuation.

Spanking of young children: do immigrant and U.S.-born Hispanic parents differ?

PubMed

Lee, Shawna J; Altschul, Inna

2015-02-01

Building on prior research showing fewer parenting risk behaviors and lower levels of harsh punishment among less acculturated Hispanic parents, we tested the hypothesis that foreign-born (FB; immigrant) Hispanic parents use less spanking toward children at 3 years and 5 years of age than U.S.-born Hispanic parents. We also examined whether other indicators of acculturation-endorsement of traditional gender norms and religiosity-showed any direct or indirect effects in explaining the hypothesized association. Path model analyses were conducted with a sample of Hispanic mothers (n = 1,089) and fathers (n = 650). Cross-sectional and time lagged path models controlling for a wide range of psychosocial and demographic confounds indicated that, when compared with U.S.-born Hispanic parents, FB Hispanic mothers and fathers used less spanking toward their young children. In cross-sectional analysis only, mothers' greater endorsement of traditional gender norms had small protective effects on spanking. Although fathers' endorsement of traditional gender norms was not a significant direct predictor of spanking, there was a significant indirect effect of nativity status on spanking mediated by endorsement of traditional gender norms. Religiosity showed no relation to spanking for either mothers or fathers. Immigrant status may be an important protective factor that is associated with lower levels of parenting aggression among Hispanic mothers and fathers living in the United States. © The Author(s) 2014.

Calculation of organ doses in x-ray examinations of premature babies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smans, Kristien; Tapiovaara, Markku; Cannie, Mieke

Lung disease represents one of the most life-threatening conditions in prematurely born children. In the evaluation of the neonatal chest, the primary and most important diagnostic study is the chest radiograph. Since prematurely born children are very sensitive to radiation, those radiographs may lead to a significant radiation detriment. Knowledge of the radiation dose is therefore necessary to justify the exposures. To calculate doses in the entire body and in specific organs, computational models of the human anatomy are needed. Using medical imaging techniques, voxel phantoms have been developed to achieve a representation as close as possible to the anatomicalmore » properties. In this study two voxel phantoms, representing prematurely born babies, were created from computed tomography- and magnetic resonance images: Phantom 1 (1910 g) and Phantom 2 (590 g). The two voxel phantoms were used in Monte Carlo calculations (MCNPX) to assess organ doses. The results were compared with the commercially available software package PCXMC in which the available mathematical phantoms can be downsized toward the prematurely born baby. The simple phantom-scaling method used in PCXMC seems to be sufficient to calculate doses for organs within the radiation field. However, one should be careful in specifying the irradiation geometry. Doses in organs that are wholly or partially outside the primary radiation field depend critically on the irradiation conditions and the phantom model.« less

Model documentation: Electricity Market Module, Electricity Fuel Dispatch Submodule

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This report documents the objectives, analytical approach and development of the National Energy Modeling System Electricity Fuel Dispatch Submodule (EFD), a submodule of the Electricity Market Module (EMM). The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, model source code, and forecast results generated through the synthesis and scenario development based on these components.

Electrical conductivity modeling in fractal non-saturated porous media

NASA Astrophysics Data System (ADS)

Wei, W.; Cai, J.; Hu, X.; Han, Q.

2016-12-01

The variety of electrical conductivity in non-saturated conditions is important to study electric conduction in natural sedimentary rocks. The electrical conductivity in completely saturated porous media is a porosity-function representing the complex connected behavior of single conducting phases (pore fluid). For partially saturated conditions, the electrical conductivity becomes even more complicated since the connectedness of pore. Archie's second law is an empirical electrical conductivity-porosity and -saturation model that has been used to predict the formation factor of non-saturated porous rock. However, the physical interpretation of its parameters, e.g., the cementation exponent m and the saturation exponent n, remains questionable. On basis of our previous work, we combine the pore-solid fractal (PSF) model to build an electrical conductivity model in non-saturated porous media. Our theoretical porosity- and saturation-dependent models contain endmember properties, such as fluid electrical conductivities, pore fractal dimension and tortuosity fractal dimension (representing the complex degree of electrical flowing path). We find the presented model with non-saturation-dependent electrical conductivity datasets indicate excellent match between theory and experiments. This means the value of pore fractal dimension and tortuosity fractal dimension change from medium to medium and depends not only on geometrical properties of pore structure but also characteristics of electrical current flowing in the non-saturated porous media.

Label-free impedimetric biosensor for Salmonella Typhimurium detection based on poly [pyrrole-co-3-carboxyl-pyrrole] copolymer supported aptamer.

PubMed

Sheikhzadeh, E; Chamsaz, M; Turner, A P F; Jager, E W H; Beni, V

2016-06-15

The Gram-negative bacterium, Salmonella Typhimurium (S. Typhimurium) is a food borne pathogen responsible for numerous hospitalisations and deaths all over the world. Conventional detection methods for pathogens are time consuming and labour-intensive. Hence, there is considerable interest in faster and simpler detection methods. Polypyrrole-based polymers, due to their intrinsic chemical and electrical properties, have been demonstrated to be valuable candidates for the fabrication of chemo/biosensors and functional surfaces. Similarly aptamers have been shown to be good alternatives to antibodies in the development of affinity biosensors. In this study, we report on the combination of poly [pyrrole-co-3-carboxyl-pyrrole] copolymer and aptamer for the development of a label-less electrochemical biosensor suitable for the detection of S. Typhimurium. Impedimetric measurements were facilitated by the effect of the aptamer/target interaction on the intrinsic conjugation of the poly [pyrrole-co-3-carboxyl-pyrrole] copolymer and subsequently on its electrical properties. The aptasensor detected S. Typhimurium in the concentration range 10(2)-10(8) CFU mL(-1) with high selectivity over other model pathogens and with a limit of quantification (LOQ) of 100 CFU mL(-1) and a limit of detection (LOD) of 3 CFU mL(-1). The suitability of the aptasensor for real sample detection was demonstrated via recovery studies performed in spiked apple juice samples. We envisage this to be a viable approach for the inexpensive and rapid detection of pathogens in food, and possibly in other environmental samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Higher-Order Extended Lagrangian Born-Oppenheimer Molecular Dynamics for Classical Polarizable Models.

PubMed

Albaugh, Alex; Head-Gordon, Teresa; Niklasson, Anders M N

2018-02-13

Generalized extended Lagrangian Born-Oppenheimer molecular dynamics (XLBOMD) methods provide a framework for fast iteration-free simulations of models that normally require expensive electronic ground state optimizations prior to the force evaluations at every time step. XLBOMD uses dynamically driven auxiliary degrees of freedom that fluctuate about a variationally optimized ground state of an approximate "shadow" potential which approximates the true reference potential. While the requirements for such shadow potentials are well understood, constructing such potentials in practice has previously been ad hoc, and in this work, we present a systematic development of XLBOMD shadow potentials that match the reference potential to any order. We also introduce a framework for combining friction-like dissipation for the auxiliary degrees of freedom with general-order integration, a combination that was not previously possible. These developments are demonstrated with a simple fluctuating charge model and point induced dipole polarization models.

An Overview of Animal Models for Arthropod-Borne Viruses.

PubMed

Reynolds, Erin S; Hart, Charles E; Hermance, Meghan E; Brining, Douglas L; Thangamani, Saravanan

2017-06-01

Arthropod-borne viruses (arboviruses) have continued to emerge in recent years, posing a significant health threat to millions of people worldwide. The majority of arboviruses that are pathogenic to humans are transmitted by mosquitoes and ticks, but other types of arthropod vectors can also be involved in the transmission of these viruses. To alleviate the health burdens associated with arbovirus infections, it is necessary to focus today's research on disease control and therapeutic strategies. Animal models for arboviruses are valuable experimental tools that can shed light on the pathophysiology of infection and will enable the evaluation of future treatments and vaccine candidates. Ideally an animal model will closely mimic the disease manifestations observed in humans. In this review, we outline the currently available animal models for several viruses vectored by mosquitoes, ticks, and midges, for which there are no standardly available vaccines or therapeutics.

Welding apparatus and methods for using ultrasonic sensing

DOEpatents

McJunkin, Timothy R.; Johnson, John A.; Larsen, Eric D.; Smartt, Herschel B.

2006-08-22

A welding apparatus using ultrasonic sensing is described and which includes a movable welder having a selectively adjustable welding head for forming a partially completed weld in a weld seam defined between adjoining metal substrates; an ultrasonic assembly borne by the moveable welder and which is operable to generate an ultrasonic signal which is directed toward the partially completed weld, and is further reflected from same; and a controller electrically coupled with the ultrasonic assembly and controllably coupled with the welding head, and wherein the controller receives information regarding the ultrasonic signal and in response to the information optimally positions the welding head relative to the weld seam.

Heterogeneity, Mixing, and the Spatial Scales of Mosquito-Borne Pathogen Transmission

PubMed Central

Perkins, T. Alex; Scott, Thomas W.; Le Menach, Arnaud; Smith, David L.

2013-01-01

The Ross-Macdonald model has dominated theory for mosquito-borne pathogen transmission dynamics and control for over a century. The model, like many other basic population models, makes the mathematically convenient assumption that populations are well mixed; i.e., that each mosquito is equally likely to bite any vertebrate host. This assumption raises questions about the validity and utility of current theory because it is in conflict with preponderant empirical evidence that transmission is heterogeneous. Here, we propose a new dynamic framework that is realistic enough to describe biological causes of heterogeneous transmission of mosquito-borne pathogens of humans, yet tractable enough to provide a basis for developing and improving general theory. The framework is based on the ecological context of mosquito blood meals and the fine-scale movements of individual mosquitoes and human hosts that give rise to heterogeneous transmission. Using this framework, we describe pathogen dispersion in terms of individual-level analogues of two classical quantities: vectorial capacity and the basic reproductive number, . Importantly, this framework explicitly accounts for three key components of overall heterogeneity in transmission: heterogeneous exposure, poor mixing, and finite host numbers. Using these tools, we propose two ways of characterizing the spatial scales of transmission—pathogen dispersion kernels and the evenness of mixing across scales of aggregation—and demonstrate the consequences of a model's choice of spatial scale for epidemic dynamics and for estimation of , both by a priori model formulas and by inference of the force of infection from time-series data. PMID:24348223

Age of Migration Differentials in Life Expectancy with Cognitive Impairment: 20-Year Findings From the Hispanic-EPESE.

PubMed

Garcia, Marc A; Saenz, Joseph L; Downer, Brian; Chiu, Chi-Tsun; Rote, Sunshine; Wong, Rebeca

2017-05-09

To examine differences in life expectancy with cognitive impairment among older Mexican adults according to nativity (U.S.-born/foreign-born) and among immigrants, age of migration to the United States. This study employs 20 years of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly to estimate the proportion of life spent cognitively healthy and cognitively impaired prior to death among older Mexican adults residing in the southwestern United States. We combine age-specific mortality rates with age-specific prevalence of cognitive impairment, defined as a Mini-Mental Status Exam score of less than 21 points to calculate Sullivan-based life table models with and without cognitive impairment in later life. Foreign-born Mexican immigrants have longer total life expectancy and comparable cognitive healthy life expectancy regardless of gender compared to U.S.-born Mexican-Americans. However, the foreign-born spend a greater number of years after age 65 with cognitive impairment relative to their U.S.-born counterparts. Furthermore, we document an advantage in life expectancy with cognitive impairment and proportion of years after age 65 cognitively healthy among mid-life immigrant men and women relative to early- and late-life migrants. The relationship between nativity, age of migration, and life expectancy with cognitive impairment means that the foreign-born are in more need of support and time-intensive care in late life. This issue merits special attention to develop appropriate and targeted screening efforts that reduce cognitive decline for diverse subgroups of older Mexican-origin adults as they age. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Convergence of body mass index of immigrants to the Canadian-born population: evidence from the National Population Health Survey (1994-2006).

PubMed

Setia, Maninder Singh; Quesnel-Vallee, Amelie; Abrahamowicz, Michal; Tousignant, Pierre; Lynch, John

2009-01-01

Recent immigrants typically have better physical health than the native born population. However, this 'healthy immigrant effect' tends to gradually wane over time, with increasing length of residence in the host country. To assess whether the body mass index (BMI) of different immigrant groups converged to the Canadian population's levels, we estimated 12-year trajectories of changes in BMI (accounting for socio-demographic changes). Using data from seven longitudinal waves of the National Population Health Survey (1994 through 2006), we compared the changes in BMI (kg/m(2)) among three groups: white immigrants, non-white immigrants and Canadian born, aged 18-54 at baseline. We applied linear random effects models to evaluate these BMI separately in 2,504 males and 2,960 females. BMI increased in Canadian born, white immigrants, and non-white immigrants over the 12-year period. However, non-white immigrants (males and females) had a lower mean BMI than Canadian born individuals during this period [Males: -2.27, 95% Confidence interval (CI) -3.02 to -1.53; Females: -1.84, 95% CI -2.79 to -0.90]. In contrast, the mean BMI in white male immigrants and Canadian born individuals were similar (-0.32, 95% CI -0.91 to 0.27). Even after adjusting for time since immigration, non-white immigrants had lower BMI than white immigrants. White male immigrants were the only sub-group to converge to the BMI of the Canadian born population. These results indicate that the loss of 'healthy immigrant effect' with regard to convergence of BMI to Canadian levels may not be experienced equally by all immigrants in Canada.

Mortality of Siberian polecats and black-footed ferrets released onto prairie dog colonies

USGS Publications Warehouse

Biggins, D.E.; Miller, B.J.; Hanebury, L.R.; Powell, R.A.

2011-01-01

Black-footed ferrets (Mustela nigripes) likely were extirpated from the wild in 19851986, and their repatriation depends on captive breeding and reintroduction. Postrelease survival of animals can be affected by behavioral changes induced by captivity. We released neutered Siberian polecats (M. eversmanii), close relatives of ferrets, in 19891990 on black-tailed prairie dog (Cynomys ludovicianus) colonies in Colorado and Wyoming initially to test rearing and reintroduction techniques. Captive-born polecats were reared in cages or cages plus outdoor pens, released from elevated cages or into burrows, and supplementally fed or not fed. We also translocated wild-born polecats from China in 1990 and released captive-born, cage-reared black-footed ferrets in 1991, the 1st such reintroduction of black-footed ferrets. We documented mortality for 55 of 92 radiotagged animals in these studies, mostly due to predation (46 cases). Coyotes (Canis latrans) killed 31 ferrets and polecats. Supplementally fed polecats survived longer than nonprovisioned polecats. With a model based on deaths per distance moved, survival was highest for wild-born polecats, followed by pen-experienced, then cage-reared groups. Indexes of abundance (from spotlight surveys) for several predators were correlated with mortality rates of polecats and ferrets due to those predators. Released black-footed ferrets had lower survival rates than their ancestral population in Wyoming, and lower survival than wild-born and translocated polecats, emphasizing the influence of captivity. Captive-born polecats lost body mass more rapidly postrelease than did captive-born ferrets. Differences in hunting efficiency and prey selection provide further evidence that these polecats and ferrets are not ecological equivalents in the strict sense. ?? 2011 American Society of Mammalogists.

Nativity status and oral cancer survival in the United States: implications for dental clinical practice.

PubMed

Agaku, Israel T; Adisa, Akinyele O

2014-04-01

Nativity status is a major determinant of health and healthcare access in the United States. This study compared oral squamous cell carcinoma (OSCC) survival between US-born and foreign-born patients. Data were obtained from the 1988-2008 Surveillance, Epidemiology and End Results database. A Cox proportional hazards multivariate model was used to assess the eff ect of birthplace on OSCC survival, adjusting for other sociodemographic and clinical covariates. US-born patients had a higher median survival time (19.3 years; 95% confidence interval [CI]: 18.6-19.7) compared to foreign-born patients (10.7 years; 95% CI: 10.1-11.3). After adjusting for other factors, being born in the US conferred a modest protective eff ect from OSCC mortality (hazard ratio [HR] = 0.93, 95% CI: 0.87- 0.99). Other factors that conferred better survival included involvement of paired structures (HR = 0.65; 95% CI: 0.58- 0.74), lip involvement rather than tongue lesions (HR = 0.76; 95% CI: 0.71-0.82), and receipt of either surgery (HR = 0.89; 95% CI: 0.84-0.94) or radiation therapy (HR = 0.92; 95% CI: 0.87-0.97). US-born patients had significantly better OSCC survival compared to their foreign-born counterparts. This underscores the need for enhanced and sustained efforts to improve access to healthcare among immigrant populations. In addition, oral health professionals such as general dentists, oral pathologists, and oral surgeons providing care to immigrant patients should ensure that reasonable efforts are made to communicate effectively with patients with language barriers, especially in high-stake conditions such as cancer. This may help increase such patients' awareness of treatment provided and the critical issues regarding cancer care, resulting in enhanced treatment outcome.

Associations between birth at, or after, 41 weeks gestation and perinatal encephalopathy: a cohort study

PubMed Central

Yau, Christopher; Winter, Cathy; Draycott, Timothy; Rasmussen, Finn

2018-01-01

Background Preterm birth causes long-term problems, even for infants born 1 or 2 weeks early. However, less is known about infants born after their due date and over a quarter of infants are born over 1 week late, and many still remain undelivered after 2 weeks. The aim of this work is to quantify the risks of infants developing encephalopathy when birth occurs after the due date, and if other proposed risk factors modify this relationship. Methods The dataset contain information on 4 036 346 infants born in Sweden between 1973 and 2012. Exposure was defined as birth 7, or more, days after the infants’ due date. The primary outcome was the development of neonatal encephalopathy (defined as seizures, encephalopathy or brain injury caused by asphyxia or with unspecified cause). Covariates were selected as presumed confounders a priori. Results 28.4% infants were born 1 or more weeks after their due date. An infant’s risk of being born with encephalopathy was higher in the post 41 weeks group in the unadjusted (OR 1.40 (95% CI 1.32 to 1.49)) and final model (OR 1.38 (95% CI 1.29 to 1.47)), with the relative odds of encephalopathy increasing by an estimated 20% per week after the due date, and modified by maternal age (P=0.022). Conclusions Singleton infants born at, or after, 41 weeks gestation have lower Apgar scores and higher risk of developing encephalopathy in the newborn period, and the association appeared more marked in older mothers. These data could be useful if provided to women as part of their decision-making. PMID:29637179

Use of dental services by immigration status in the United States.

PubMed

Wilson, Fernando A; Wang, Yang; Stimpson, Jim P; McFarland, Kimberly K; Singh, Karan P

2016-03-01

There is limited research with mixed findings comparing differences in oral health outcomes and the use of dental services by immigration status. The authors conducted a study by reviewing nationally representative data to describe differences in dental care among noncitizens, naturalized citizens, and US-born citizens in the United States. The authors used nationally representative data from the 2008-2012 Medical Expenditure Panel Survey to examine dental care for US-born citizens, naturalized citizens, and noncitizens 18 years and older. Total analytical sample size was 98,107 adults. They used multivariate logistic regression to model dental service use adjusting for confounding factors. Naturalized citizens and noncitizens were significantly less likely to have at least 1 dental visit within 12 months (39.5% and 23.1%, respectively) compared with US-born citizens (43.6%; P < .001). Among users, a smaller proportion of comprehensive examination visits were for naturalized citizens and noncitizens (75.9% and 71.4%, respectively) compared with US-born citizens (82.8%; P < .01). Noncitizen visits to dentists were also more likely to involve tooth extraction compared with those of US-born citizens (11.3% versus 8.8%; P < .01). Multivariate logistic regression suggests both non- and naturalized citizens had lower adjusted odds of having a comprehensive examination compared with US-born citizens during a visit (P < .01). Noncitizens and naturalized citizens had a lower rate of dental service use, and noncitizens were more likely to have had tooth extraction compared with US-born citizens. Increased outreach efforts tailored to noncitizens and naturalized citizens who are at high risk of experiencing dental problems are needed, particularly to address misperceptions on the necessity of preventive dental visits. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

Maternal hypothyroidism in the perinatal period and childhood asthma in the offspring.

PubMed

Liu, X; Andersen, S L; Olsen, J; Agerbo, E; Schlünssen, V; Dharmage, S C; Munk-Olsen, T

2018-04-01

There is increasing interest in the possible link between maternal hypothyroidism in the perinatal period and childhood asthma risk. We explored this in this study while accounting for the timing of hypothyroidism diagnosis. Further, we evaluated whether the risk was moderated by thyroid hormone treatment during pregnancy. We conducted a population-based cohort study using Danish national registers. All live-born singletons in Denmark from 1998 to 2007 were identified. Maternal hypothyroidism and asthma in the children were defined by data from the Patient Register and Prescription Registry. We estimated incidence rate ratios (IRRs) of asthma among children born to hypothyroid mothers versus children born to mothers with no recorded thyroid dysfunction using Poisson regression models. Of 595 669 children, 3524 children were born to mothers with hypothyroidism diagnosed before delivery and 4664 diagnosed after delivery. Overall, 48 990 children received treatment for asthma. The IRRs of asthma was 1.16 (95% confidence interval (CI): 1.03-1.30) and 1.12 (95% CI: 1.02-1.24) for children born to mothers with hypothyroidism diagnosed before and after delivery, compared to children born to mothers with no thyroid dysfunction. The highest risk was observed among children born to mothers with hypothyroidism diagnosed before delivery who did not receive thyroid hormone treatment during pregnancy (IRR=1.37, 95% CI: 1.04-1.80). Our findings suggest that maternal hypothyroidism, especially when it is untreated, increases childhood asthma risk. Early detection and appropriate treatment of hypothyroidism in pregnant women may be an area for possible prevention of childhood asthma. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

[Associated factors in newborns with intrauterine growth retardation].

PubMed

Thompson-Chagoyán, Oscar C; Vega-Franco, Leopoldo

2008-01-01

To identify the risk factors implicated in the intrauterine growth retardation (IUGR) of neonates born in a social security institution. Case controls design study in 376 neonates: 188 with IUGR (weight < 10 percentile) and 188 without IUGR. When they born, information about 30 variables of risk for IUGR were obtained from mothers. Risk analysis and logistical regression (stepwise) were used. Odds ratios were significant for 12 of the variables. The model obtains by stepwise regression included: weight gain at pregnancy, prenatal care attendance, toxemia, chocolate ingestion, father's weight, and the environmental house. Must of the variables included in the model are related to socioeconomic disadvantages related to the risk of RCIU in the population.

Model reference adaptive control for the azimuth-pointing system of a balloon-borne stabilized platform

NASA Technical Reports Server (NTRS)

Lubin, Philip M.; Tomizuka, Masayoshi; Chingcuanco, Alfredo O.; Meinhold, Peter R.

1991-01-01

A balloon-born stabilized platform has been developed for the remotely operated altitude-azimuth pointing of a millimeter wave telescope system. This paper presents a development and implementation of model reference adaptive control (MRAC) for the azimuth-pointing system of the stabilized platform. The primary goal of the controller is to achieve pointing rms better than 0.1 deg. Simulation results indicate that MRAC can achieve pointing rms better than 0.1 deg. Ground test results show pointing rms better than 0.03 deg. Data from the first flight at the National Scientific Balloon Facility (NSBF) Palestine, Texas show pointing rms better than 0.02 deg.

Indoor Air Nuclear, Biological, and Chemical Health Modeling and Assessment System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stenner, Robert D.; Hadley, Donald L.; Armstrong, Peter R.

2001-03-01

Indoor air quality effects on human health are of increasing concern to public health agencies and building owners. The prevention and treatment of 'sick building' syndrome and the spread of air-borne diseases in hospitals, for example, are well known priorities. However, increasing attention is being directed to the vulnerability of our public buildings/places, public security and national defense facilities to terrorist attack or the accidental release of air-borne biological pathogens, harmful chemicals, or radioactive contaminants. The Indoor Air Nuclear, Biological, and Chemical Health Modeling and Assessment System (IA-NBC-HMAS) was developed to serve as a health impact analysis tool for usemore » in addressing these concerns. The overall goal was to develop a user-friendly fully functional prototype Health Modeling and Assessment system, which will operate under the PNNL FRAMES system for ease of use and to maximize its integration with other modeling and assessment capabilities accessible within the FRAMES system (e.g., ambient air fate and transport models, water borne fate and transport models, Physiologically Based Pharmacokinetic models, etc.). The prototype IA-NBC-HMAS is designed to serve as a functional Health Modeling and Assessment system that can be easily tailored to meet specific building analysis needs of a customer. The prototype system was developed and tested using an actual building (i.e., the Churchville Building located at the Aberdeen Proving Ground) and release scenario (i.e., the release and measurement of tracer materials within the building) to ensure realism and practicality in the design and development of the prototype system. A user-friendly "demo" accompanies this report to allow the reader the opportunity for a "hands on" review of the prototype system's capability.« less

Differences in hospital attendance for anaphylaxis between immigrants and non-immigrants: a cohort study.

PubMed

Norredam, M; Sheikh, A; Dynnes Svendsen, K; Holm Petersen, J; Garvey, L H; Kristiansen, M

2016-07-01

The impact of migration on the risk of anaphylaxis remains unknown. We hypothesized that non-Western immigrants have a lower incidence of anaphylaxis compared to Danish-born. We investigated variations in hospital attendance for anaphylaxis between immigrants and Danish-born including time- and age- trends. A register-based, historical prospective cohort design. Refugees or family reunified immigrants (n = 127 250) who, between January 1, 1994 and December 31, 2010, obtained residency permits in Denmark were included and matched in a 1 : 6 ratio on age and sex with Danish-born individuals (n = 740 600). Personal identification numbers were cross-linked to the Danish National Patient Registry identifying all first-time hospital attendances for anaphylaxis from January 1, 1994 and December 31, 2010. Incidence rate ratios were estimated, stratified for sex and region of birth, adjusting for age using a Cox regression model including the influence of duration of residence and age when residence was obtained. In total 1053 hospital attendances for anaphylaxis were identified: 89 among non-Western immigrants, 9 among Western immigrants and 955 among Danish-born patients. Both male (RR = 0.65; 95%CI: 0.46;0.90) and female (RR = 0.64; 95%CI: 0.48;0.85) non-Western immigrants had a significantly lower risk ratio of hospital attendance for anaphylaxis compared to Danish-born. Compared to Danish-born, non-Western immigrants living in Denmark during the entire follow-up period also showed a decreased risk (RR = 0.65; 95%CI: 0.34;1.25). Compared to Danish-born, non-Western immigrants who obtained residence permission as children had a decreased risk of hospital attendance for anaphylaxis (RR = 0.48; 95%CI: 0.25;0.91). This Danish register-based study using nationwide data revealed fewer hospital attendances for anaphylaxis among non-Western immigrants compared to Danish-born; however this protection was lost over time. © 2016 John Wiley & Sons Ltd.

Risk of Allergic Rhinitis, Allergic Conjunctivitis, and Eczema in Children Born to Mothers with Gum Inflammation during Pregnancy

PubMed Central

Hsieh, Vivian Chia-Rong; Liu, Chin-Chen; Hsiao, Yu-Chen; Wu, Trong-Neng

2016-01-01

Purpose Despite links between maternal and child health status, evidence on the association between gum infection in pregnant mothers and childhood allergies is scarce. We aim to evaluate the risk of developing allergy in children born to periodontal mothers in a nationwide study. Methods We conducted a 9-year population-based, retrospective cohort study using Taiwan’s National Health Insurance database. A study cohort of 42,217 newborns born to mothers with periodontal disease during pregnancy was identified in 2001 and matched with 42,334 babies born to mothers without any infection (control) by mother’s age at delivery and baby sex. With a follow-up period from 2001 to 2010, we observed the incidence of allergic rhinitis (AR), allergic conjunctivitis (AC), and eczema in these children. Cox proportional hazards regression models were performed with premature deaths as competing risk for the estimation of allergic disease risks. Results Nine-year cumulative incidences were the highest among children born to periodontal mothers; they reached 46.8%, 24.2%, and 40.4% (vs. 39.5%, 18.3% and 34.8% in control) for AR, AC, and eczema, respectively. Our results showed moderately increased risks for the allergies in children born to periodontal mothers relative to their matched non-inflammatory control (adjusted HRs: 1.17, 95% CI: 1.15–1.20; 1.27, 1.24–1.31; 1.14, 1.12–1.17, respectively). Because the impact of food consumption and living environment cannot be considered using insurance data, we attempted to control it by adjusting for parental income and mother’s residential area. Conclusions Overall cumulative incidence and risks of children born to periodontal mothers for AR, AC, and eczema are significantly higher than those born to non-inflammatory mothers. Gum infection in women during pregnancy is an independent risk factor for allergic diseases in children, thus its intergenerational consequences should be considered in gestational care. PMID:27224053

Risk of Allergic Rhinitis, Allergic Conjunctivitis, and Eczema in Children Born to Mothers with Gum Inflammation during Pregnancy.

PubMed

Hsieh, Vivian Chia-Rong; Liu, Chin-Chen; Hsiao, Yu-Chen; Wu, Trong-Neng

2016-01-01

Despite links between maternal and child health status, evidence on the association between gum infection in pregnant mothers and childhood allergies is scarce. We aim to evaluate the risk of developing allergy in children born to periodontal mothers in a nationwide study. We conducted a 9-year population-based, retrospective cohort study using Taiwan's National Health Insurance database. A study cohort of 42,217 newborns born to mothers with periodontal disease during pregnancy was identified in 2001 and matched with 42,334 babies born to mothers without any infection (control) by mother's age at delivery and baby sex. With a follow-up period from 2001 to 2010, we observed the incidence of allergic rhinitis (AR), allergic conjunctivitis (AC), and eczema in these children. Cox proportional hazards regression models were performed with premature deaths as competing risk for the estimation of allergic disease risks. Nine-year cumulative incidences were the highest among children born to periodontal mothers; they reached 46.8%, 24.2%, and 40.4% (vs. 39.5%, 18.3% and 34.8% in control) for AR, AC, and eczema, respectively. Our results showed moderately increased risks for the allergies in children born to periodontal mothers relative to their matched non-inflammatory control (adjusted HRs: 1.17, 95% CI: 1.15-1.20; 1.27, 1.24-1.31; 1.14, 1.12-1.17, respectively). Because the impact of food consumption and living environment cannot be considered using insurance data, we attempted to control it by adjusting for parental income and mother's residential area. Overall cumulative incidence and risks of children born to periodontal mothers for AR, AC, and eczema are significantly higher than those born to non-inflammatory mothers. Gum infection in women during pregnancy is an independent risk factor for allergic diseases in children, thus its intergenerational consequences should be considered in gestational care.

An effective medium approach to modelling the pressure-dependent electrical properties of porous rocks

NASA Astrophysics Data System (ADS)

Han, Tongcheng

2018-07-01

Understanding the electrical properties of rocks under varying pressure is important for a variety of geophysical applications. This study proposes an approach to modelling the pressure-dependent electrical properties of porous rocks based on an effective medium model. The so-named Textural model uses the aspect ratios and pressure-dependent volume fractions of the pores and the aspect ratio and electrical conductivity of the matrix grains. The pores were represented by randomly oriented stiff and compliant spheroidal shapes with constant aspect ratios, and their pressure-dependent volume fractions were inverted from the measured variation of total porosity with differential pressure using a dual porosity model. The unknown constant stiff and compliant pore aspect ratios and the aspect ratio and electrical conductivity of the matrix grains were inverted by best fitting the modelled electrical formation factor to the measured data. Application of the approach to three sandstone samples covering a broad porosity range showed that the pressure-dependent electrical properties can be satisfactorily modelled by the proposed approach. The results demonstrate that the dual porosity concept is sufficient to explain the electrical properties of porous rocks under pressure through the effective medium model scheme.

Modeling and simulation of deformation of hydrogels responding to electric stimulus.

PubMed

Li, Hua; Luo, Rongmo; Lam, K Y

2007-01-01

A model for simulation of pH-sensitive hydrogels is refined in this paper to extend its application to electric-sensitive hydrogels, termed the refined multi-effect-coupling electric-stimulus (rMECe) model. By reformulation of the fixed-charge density and consideration of finite deformation, the rMECe model is able to predict the responsive deformations of the hydrogels when they are immersed in a bath solution subject to externally applied electric field. The rMECe model consists of nonlinear partial differential governing equations with chemo-electro-mechanical coupling effects and the fixed-charge density with electric-field effect. By comparison between simulation and experiment extracted from literature, the model is verified to be accurate and stable. The rMECe model performs quantitatively for deformation analysis of the electric-sensitive hydrogels. The influences of several physical parameters, including the externally applied electric voltage, initial fixed-charge density, hydrogel strip thickness, ionic strength and valence of surrounding solution, are discussed in detail on the displacement and average curvature of the hydrogels.

Prevalence and risk factors of type 2 diabetes in older Vietnam-born Australians.

PubMed

Tran, Duong Thuy; Jorm, Louisa R; Johnson, Maree; Bambrick, Hilary; Lujic, Sanja

2014-02-01

Vietnamese immigrants in Australia represent the second largest Vietnamese community in developed countries, following the United States. However, limited information is available about prevalence of type 2 diabetes (T2D) and the relative roles of socio-demographic characteristics, lifestyle factors, and Vietnamese ethnicity per se in this population. This study investigated the prevalence of T2D and its risk factors in older Vietnam-born Australians, in comparison to native-born Australians. The study used baseline questionnaire data from 787 Vietnam- and 196,866 Australia-born individuals (≥45 years), who participated in the 45 and Up Study, which is Australia's largest population-based cohort study. Country of birth specific prevalence of T2D and its risk factors were age-standardised to the 2006 Australian population (≥45 years). Multivariable logistic regression models were built for each group to assess the relationship between T2D and socio-demographic characteristics, family history of diabetes, lifestyle factors and health status. Compared to Australia-born counterparts, Vietnam-born individuals had significantly (p < 0.001) higher age-standardised prevalence of T2D (14.7 vs 7.4 %) and significantly (p < 0.001) lower levels of vegetable consumption (≥5 serves/day, 19.4 vs 33.5 %), physical activity (≥5 sessions/week, 68.7 vs 78.5 %) and overweight and obesity (body mass index ≥25 kg/m(2), 21.5 vs 62.7 %). The increased risk of T2D associated with a family history of diabetes for Vietnam-born people [adjusted odds ratio (OR) 7.14, 95 % CI 4.15-12.28] was almost double that for Australia-born people (OR 3.77, 95 % CI 3.63-3.90). The patterns of association between T2D and other factors were similar between the two groups. The findings suggest a genetic predisposition to T2D in people of Vietnamese ethnicity. Reducing lifestyle risk factors for diabetes and better management of diabetes are priorities for Vietnam-born populations.

Abrupt Decline in Tuberculosis among Foreign-Born Persons in the United States

PubMed Central

Baker, Brian J.; Winston, Carla A.; Liu, Yecai; France, Anne Marie; Cain, Kevin P.

2016-01-01

While the number of reported tuberculosis (TB) cases in the United States has declined over the past two decades, TB morbidity among foreign-born persons has remained persistently elevated. A recent unexpected decline in reported TB cases among foreign-born persons beginning in 2007 provided an opportunity to examine contributing factors and inform future TB control strategies. We investigated the relative influence of three factors on the decline: 1) changes in the size of the foreign-born population through immigration and emigration, 2) changes in distribution of country of origin among foreign-born persons, and 3) changes in the TB case rates among foreign-born subpopulations. Using data from the U.S. National Tuberculosis Surveillance System and the American Community Survey, we examined TB case counts, TB case rates, and population estimates, stratified by years since U.S. entry and country of origin. Regression modeling was used to assess statistically significant changes in trend. Among foreign-born recent entrants (<3 years since U.S. entry), we found a 39.5% decline (-1,013 cases) beginning in 2007 (P<0.05 compared to 2000–2007) and ending in 2011 (P<0.05 compared to 2011–2014). Among recent entrants from Mexico, 80.7% of the decline was attributable to a decrease in population, while the declines among recent entrants from the Philippines, India, Vietnam, and China were almost exclusively (95.5%–100%) the result of decreases in TB case rates. Among foreign-born non-recent entrants (≥3 years since U.S. entry), we found an 8.9% decline (-443 cases) that resulted entirely (100%) from a decrease in the TB case rate. Both recent and non-recent entrants contributed to the decline in TB cases; factors contributing to the decline among recent entrants varied by country of origin. Strategies that impact both recent and non-recent entrants (e.g., investment in overseas TB control) as well as those that focus on non-recent entrants (e.g., expanded targeted testing of high-risk subgroups among non-recent entrants) will be necessary to achieve further declines in TB morbidity among foreign-born persons. PMID:26863004

An Environmental Data Set for Vector-Borne Disease Modeling and Epidemiology

PubMed Central

Chabot-Couture, Guillaume; Nigmatulina, Karima; Eckhoff, Philip

2014-01-01

Understanding the environmental conditions of disease transmission is important in the study of vector-borne diseases. Low- and middle-income countries bear a significant portion of the disease burden; but data about weather conditions in those countries can be sparse and difficult to reconstruct. Here, we describe methods to assemble high-resolution gridded time series data sets of air temperature, relative humidity, land temperature, and rainfall for such areas; and we test these methods on the island of Madagascar. Air temperature and relative humidity were constructed using statistical interpolation of weather station measurements; the resulting median 95th percentile absolute errors were 2.75°C and 16.6%. Missing pixels from the MODIS11 remote sensing land temperature product were estimated using Fourier decomposition and time-series analysis; thus providing an alternative to the 8-day and 30-day aggregated products. The RFE 2.0 remote sensing rainfall estimator was characterized by comparing it with multiple interpolated rainfall products, and we observed significant differences in temporal and spatial heterogeneity relevant to vector-borne disease modeling. PMID:24755954

Mapping the critical gestational age at birth that alters brain development in preterm-born infants using multi-modal MRI.

PubMed

Wu, Dan; Chang, Linda; Akazawa, Kentaro; Oishi, Kumiko; Skranes, Jon; Ernst, Thomas; Oishi, Kenichi

2017-04-01

Preterm birth adversely affects postnatal brain development. In order to investigate the critical gestational age at birth (GAB) that alters the developmental trajectory of gray and white matter structures in the brain, we investigated diffusion tensor and quantitative T2 mapping data in 43 term-born and 43 preterm-born infants. A novel multivariate linear model-the change point model, was applied to detect change points in fractional anisotropy, mean diffusivity, and T2 relaxation time. Change points captured the "critical" GAB value associated with a change in the linear relation between GAB and MRI measures. The analysis was performed in 126 regions across the whole brain using an atlas-based image quantification approach to investigate the spatial pattern of the critical GAB. Our results demonstrate that the critical GABs are region- and modality-specific, generally following a central-to-peripheral and bottom-to-top order of structural development. This study may offer unique insights into the postnatal neurological development associated with differential degrees of preterm birth. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Climate change and temperature rise: implications on food- and water-borne diseases.

PubMed

El-Fadel, Mutasem; Ghanimeh, Sophia; Maroun, Rania; Alameddine, Ibrahim

2012-10-15

This study attempts to quantify climate-induced increases in morbidity rates associated with food- and water-borne illnesses in the context of an urban coastal city, taking Beirut-Lebanon as a study area. A Poisson generalized linear model was developed to assess the impacts of temperature on the morbidity rate. The model was used with four climatic scenarios to simulate a broad spectrum of driving forces and potential social, economic and technologic evolutions. The correlation established in this study exhibits a decrease in the number of illnesses with increasing temperature until reaching a threshold of 19.2 °C, beyond which the number of morbidity cases increases with temperature. By 2050, the results show a substantial increase in food- and water-borne related morbidity of 16 to 28% that can reach up to 42% by the end of the century under A1FI (fossil fuel intensive development) or can be reversed to ~0% under B1 (lowest emissions trajectory), highlighting the need for early mitigation and adaptation measures. Copyright © 2012 Elsevier B.V. All rights reserved.

Treecode-based generalized Born method

NASA Astrophysics Data System (ADS)

Xu, Zhenli; Cheng, Xiaolin; Yang, Haizhao

2011-02-01

We have developed a treecode-based O(Nlog N) algorithm for the generalized Born (GB) implicit solvation model. Our treecode-based GB (tGB) is based on the GBr6 [J. Phys. Chem. B 111, 3055 (2007)], an analytical GB method with a pairwise descreening approximation for the R6 volume integral expression. The algorithm is composed of a cutoff scheme for the effective Born radii calculation, and a treecode implementation of the GB charge-charge pair interactions. Test results demonstrate that the tGB algorithm can reproduce the vdW surface based Poisson solvation energy with an average relative error less than 0.6% while providing an almost linear-scaling calculation for a representative set of 25 proteins with different sizes (from 2815 atoms to 65456 atoms). For a typical system of 10k atoms, the tGB calculation is three times faster than the direct summation as implemented in the original GBr6 model. Thus, our tGB method provides an efficient way for performing implicit solvent GB simulations of larger biomolecular systems at longer time scales.

Immigrant residential segregation in U.S. metropolitan areas, 1990-2000.

PubMed

Iceland, John; Scopilliti, Melissa

2008-02-01

This paper examines the extent of spatial assimilation among immigrants of different racial and ethnic origins. We use restricted data from the 1990 and 2000 censuses to calculate the levels of dissimilarity by race and Hispanic origin, nativity, and year of entry, and then run multivariate models to examine these relationships. The findings provide broad support for spatial assimilation theory. Foreign-born Hispanics, Asians, and blacks are more segregated from native-born non-Hispanic whites than are the U.S.-born of these groups. The patterns for Hispanics and Asians can be explained by the average characteristics of the foreign-born that are generally associated with higher levels of segregation, such as lower levels of income, English language ability, and home ownership. We also find that immigrants who have been in the United States for longer periods are generally less segregated than new arrivals, and once again, much of this difference can be attributed to the characteristics of immigrants. However, patterns also vary across groups. Levels of segregation are much higher for black immigrants than for Asian, Hispanic, and white immigrants. In addition, because black immigrants are, on average, of higher socioeconomic status than native-born blacks, such characteristics do not help explain their very high levels of segregation.

Hospitalisation for depressive disorder following unemployment--differentials by gender and immigrant status: a population-based cohort study in Sweden.

PubMed

Hollander, Anna-Clara; Bruce, Daniel; Ekberg, Jan; Burström, Bo; Ekblad, Solvig

2013-10-01

The association between unemployment and poor mental health in general is explained by both causation and selection. The aim was to study whether experiencing unemployment was a risk factor for hospitalisation for depressive disorder specifically, and whether gender and immigrant status modified the hypothesised risk. A register-based prospective cohort study, 2000-2006, of persons aged 18-64 with a strong connection to the Swedish labour market. hospital admission for a depressive episode; F32 in International Classification of Diseases, 10th revision. employment status. Explanatory variables: gender and immigrant status. Confounders: age group, education and marital status. Cox regression models were used to estimate HRs with 95% CIs. The cohort comprised 3 284 896 adults, 47.5% women. An excess relative risk for hospitalisation was found among those who became unemployed (HR=1.94, 95% CI 1.85 to 2.03). Foreign-born women who experienced unemployment had the highest relative risk (HR=3.47 95% CI 3.02 to 3.98). Among persons with a strong connection to the labour market experiencing unemployment, is a risk factor for hospitalisation for depressive disorders. Unemployed foreign-born women had the highest relative risk compared with all Swedish born, all foreign-born men and to employed foreign-born women.

Medical Expenditures among Immigrant and Non-Immigrant Groups in the U.S.: Findings from the Medical Expenditures Panel Survey (2000–2008)

PubMed Central

Tarraf, Wassim; Miranda, Patricia Y.; González, Hector M.

2011-01-01

Objective To examine time trends and differences in medical expenditures between non-citizens, foreign-born, and U.S.-born citizens. Methods We used multi-year Medical Expenditures Panel Survey (2000–2008) data on non-institutionalized adults in the U.S. (N=190,965). Source specific and total medical expenditures were analyzed using regression models, bootstrap prediction techniques, and linear and non-linear decomposition methods to evaluate the relationship between immigration status and expenditures, controlling for confounding effects. Results We found that the average health expenditures between 2000 and 2008 for non-citizens immigrants ($1,836) were substantially lower compared to both foreign-born ($3,737) and U.S.-born citizens ($4,478). Differences were maintained after controlling for confounding effects. Decomposition techniques showed that the main determinants of these differences were the availability of a usual source of healthcare, insurance, and ethnicity/race. Conclusion Lower healthcare expenditures among immigrants result from disparate access to healthcare. The dissipation of demographic advantages among immigrants could prospectively produce higher pressures on the U.S. healthcare system as immigrants age and levels of chronic conditions rise. Barring a shift in policy, the brunt of the effects could be borne by an already overextended public healthcare system. PMID:22222383

Nativity and neighborhood characteristics and cervical cancer stage at diagnosis and survival outcomes among Hispanic women in California.

PubMed

Gomez, Nicole; Guendelman, Sylvia; Harley, Kim G; Gomez, Scarlett Lin

2015-03-01

We examined stage of diagnosis and survival after cervical cancer among Hispanic women, and their associations with Hispanic nativity, and explored whether neighborhood socioeconomic status (SES) and residence in a Hispanic enclave modify the association of nativity with stage and survival. We used California Cancer Registry data (1994-2009) to identify 7958 Hispanic women aged 21 years and older with invasive cervical cancer. We used logistic and Cox proportional hazards models to estimate the associations between stage and mortality with nativity, neighborhood factors, and other covariates. Foreign-born women had similar adjusted relative odds of being diagnosed with stages II through IV (vs stage I) cervical cancer compared with US-born Hispanic women. However, among foreign-born women, those in low-SES-low-enclave neighborhoods were more likely to have late-stage disease than those in high-SES-low-enclave neighborhoods (adjusted odds ratio=1.91; 95% confidence interval=1.18, 3.07). Foreign-born women had lower cervical cancer mortality (adjusted hazard ratio=0.67; 95% confidence interval=0.58, 0.76) than US-born women, but only in high enclaves. Among Hispanic women, nativity, neighborhood enclaves, and SES interact in their influence on stage and survival of cervical cancer.

Epidemiological Paradox or Immigrant Vulnerability? Obesity Among Young Children of Immigrants

PubMed Central

Baker, Elizabeth H.; Rendall, Michael S.; Weden, Margaret M.

2015-01-01

According to the “immigrant epidemiological paradox,” immigrants and their children enjoy health advantages over their U.S.-born peers—advantages that diminish with greater acculturation. We investigated child obesity as a potentially significant deviation from this paradox for second-generation immigrant children. We evaluated two alternate measures of mother's acculturation: age at arrival in the United States and English language proficiency. To obtain sufficient numbers of second-generation immigrant children, we pooled samples across two related, nationally representative surveys. Each included measured (not parent-reported) height and weight of kindergartners. We also estimated models that alternately included and excluded mother's pre-pregnancy weight status as a predictor. Our findings are opposite to those predicted by the immigrant epidemiological paradox: children of U.S.-born mothers were less likely to be obese than otherwise similar children of foreign-born mothers; and the children of the least-acculturated immigrant mothers, as measured by low English language proficiency, were the most likely to be obese. Foreign-born mothers had lower (healthier) pre-pregnancy weight than U.S.-born mothers, and this was protective against their second-generation children's obesity. This protection, however, was not sufficiently strong to outweigh factors associated or correlated with the mothers' linguistic isolation and marginal status as immigrants. PMID:26111970

Epidemiological Paradox or Immigrant Vulnerability? Obesity Among Young Children of Immigrants.

PubMed

Baker, Elizabeth H; Rendall, Michael S; Weden, Margaret M

2015-08-01

According to the "immigrant epidemiological paradox," immigrants and their children enjoy health advantages over their U.S.-born peers--advantages that diminish with greater acculturation. We investigated child obesity as a potentially significant deviation from this paradox for second-generation immigrant children. We evaluated two alternate measures of mother's acculturation: age at arrival in the United States and English language proficiency. To obtain sufficient numbers of second-generation immigrant children, we pooled samples across two related, nationally representative surveys. Each included measured (not parent-reported) height and weight of kindergartners. We also estimated models that alternately included and excluded mother's pre-pregnancy weight status as a predictor. Our findings are opposite to those predicted by the immigrant epidemiological paradox: children of U.S.-born mothers were less likely to be obese than otherwise similar children of foreign-born mothers; and the children of the least-acculturated immigrant mothers, as measured by low English language proficiency, were the most likely to be obese. Foreign-born mothers had lower (healthier) pre-pregnancy weight than U.S.-born mothers, and this was protective against their second-generation children's obesity. This protection, however, was not sufficiently strong to outweigh factors associated or correlated with the mothers' linguistic isolation and marginal status as immigrants.

Hearing Loss Associated with US Military Combat Deployment

DTIC Science & Technology

2015-02-01

previous study found increased odds of hearing loss among adult Hispanics who were unmarried ,[32] whereas in this study, married members were at...deployed. In this adjusted model, male sex, being born before 1970 (compared with those born in 1980 or later), or being currently married were all...616 16.8 Education Some college or less 31,553 70.3 2732 74.6 ɘ.001 Bachelor’s or higher 13,327 29.7 928 25.4 Marital status Currently married 28,698

Estimated effects of projected climate change on the basic reproductive number of the Lyme disease vector Ixodes scapularis.

PubMed

Ogden, Nicholas H; Radojevic, Milka; Wu, Xiaotian; Duvvuri, Venkata R; Leighton, Patrick A; Wu, Jianhong

2014-06-01

The extent to which climate change may affect human health by increasing risk from vector-borne diseases has been under considerable debate. We quantified potential effects of future climate change on the basic reproduction number (R0) of the tick vector of Lyme disease, Ixodes scapularis, and explored their importance for Lyme disease risk, and for vector-borne diseases in general. We applied observed temperature data for North America and projected temperatures using regional climate models to drive an I. scapularis population model to hindcast recent, and project future, effects of climate warming on R0. Modeled R0 increases were compared with R0 ranges for pathogens and parasites associated with variations in key ecological and epidemiological factors (obtained by literature review) to assess their epidemiological importance. R0 for I. scapularis in North America increased during the years 1971-2010 in spatio-temporal patterns consistent with observations. Increased temperatures due to projected climate change increased R0 by factors (2-5 times in Canada and 1.5-2 times in the United States), comparable to observed ranges of R0 for pathogens and parasites due to variations in strains, geographic locations, epidemics, host and vector densities, and control efforts. Climate warming may have co-driven the emergence of Lyme disease in northeastern North America, and in the future may drive substantial disease spread into new geographic regions and increase tick-borne disease risk where climate is currently suitable. Our findings highlight the potential for climate change to have profound effects on vectors and vector-borne diseases, and the need to refocus efforts to understand these effects.

Maternal Mental Health Disorders and Reports to Child Protective Services: A Birth Cohort Study

PubMed Central

Hammond, Ivy; Eastman, Andrea Lane; Leventhal, John M.; Putnam-Hornstein, Emily

2017-01-01

Background. Existing literature has documented a strong relationship between parental mental illness and child maltreatment, but little is known about the prevalence of mental illness among childbearing women. In the present study, linked administrative records were used to identify the prevalence of maternal mental health (MH) disorders documented at birth and determine the associated likelihood of maltreatment reports during infancy. Materials and Methods. Vital records for California’s 2006 birth cohort were linked to hospital discharge and Child Protective Services (CPS) records. The International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) billing codes from the mother’s delivery hospitalization were used to determine diagnosed maternal MH disorders for 551,232 infants born in 2006, and reports of alleged maltreatment were documented from CPS records. Vital birth records were used to control for sociodemographic factors. Finally, the associated risk of reported maltreatment during the first year of life was examined using generalized linear models. Results. Among infants in this statewide birth cohort, 2.8% were born to a mother with a documented MH disorder, of which 41.3% had documented maternal substance abuse issues versus less than 0.5% of infants born to mothers without a diagnosed MH disorder. Further, 34.6% of infants born to mothers with a MH disorder were reported to CPS within one year, and a majority of those reports were made within the first month of life (77.2%). In contrast, among children born to mothers without a MH disorder, 4.4% were reported to CPS during infancy. After controlling for sociodemographic factors, the rate of CPS reports during infancy for infants born to mothers with a MH disorder but no substance use disorder was 2.6 times that of infants born to mothers without a MH disorder (95% CI = 2.47, 2.73). Among infants born to mothers with MH and substance use disorders, the rate of CPS reports during infancy was 5.69 times that of infants born to mothers without a MH disorder (95% CI = 5.51, 5.87). Conclusions. Administrative records provide a method for identifying infants born to mothers with MH disorders, enabling researchers to track rates over time and generate population-level data to inform policy development and improve service delivery. PMID:29084185

Neonatal atrial flutter after insertion of an intracardiac umbilical venous catheter

PubMed Central

de Almeida, Marcos Moura; Tavares, Wládia Gislaynne de Sousa; Furtado, Maria Mônica Alencar Araripe; Fontenele, Maria Marcia Farias Trajano

2016-01-01

Abstract Objective: To describe a case of neonatal atrial flutter after the insertion of an intracardiac umbilical venous catheter, reporting the clinical presentation and reviewing the literature on this subject. Case description: A late-preterm newborn, born at 35 weeks of gestational age to a diabetic mother and large for gestational age, with respiratory distress and rule-out sepsis, required an umbilical venous access. After the insertion of the umbilical venous catheter, the patient presented with tachycardia. Chest radiography showed that the catheter was placed in the position that corresponds to the left atrium, and traction was applied. The patient persisted with tachycardia, and an electrocardiogram showed atrial flutter. As the patient was hemodynamically unstable, electric cardioversion was successfully applied. Comments: The association between atrial arrhythmias and misplaced umbilical catheters has been described in the literature, but in this case, it is noteworthy that the patient was an infant born to a diabetic mother, which consists in another risk factor for heart arrhythmias. Isolated atrial flutter is a rare tachyarrhythmia in the neonatal period and its identification is essential to establish early treatment and prevent systemic complications and even death. PMID:26525686

Modified Johnson-Cook model incorporated with electroplasticity for uniaxial tension under a pulsed electric current

NASA Astrophysics Data System (ADS)

Kim, Moon-Jo; Jeong, Hye-Jin; Park, Ju-Won; Hong, Sung-Tae; Han, Heung Nam

2018-01-01

An empirical expression describing the electroplastic deformation behavior is suggested based on the Johnson-Cook (JC) model by adding several functions to consider both thermal and athermal electric current effects. Tensile deformation behaviors are carried out for an AZ31 magnesium alloy and an Al-Mg-Si alloy under pulsed electric current at various current densities with a fixed duration of electric current. To describe the flow curves under electric current, a modified JC model is proposed to take the electric current effect into account. Phenomenological descriptions of the adopted parameters in the equation are made. The modified JC model suggested in the present study is capable of describing the tensile deformation behaviors under pulsed electric current reasonably well.

Prevention and Control of Zika as a Mosquito-Borne and Sexually Transmitted Disease: A Mathematical Modeling Analysis.

PubMed

Gao, Daozhou; Lou, Yijun; He, Daihai; Porco, Travis C; Kuang, Yang; Chowell, Gerardo; Ruan, Shigui

2016-06-17

The ongoing Zika virus (ZIKV) epidemic in the Americas poses a major global public health emergency. While ZIKV is transmitted from human to human by bites of Aedes mosquitoes, recent evidence indicates that ZIKV can also be transmitted via sexual contact with cases of sexually transmitted ZIKV reported in Argentina, Canada, Chile, France, Italy, New Zealand, Peru, Portugal, and the USA. Yet, the role of sexual transmission on the spread and control of ZIKV infection is not well-understood. We introduce a mathematical model to investigate the impact of mosquito-borne and sexual transmission on the spread and control of ZIKV and calibrate the model to ZIKV epidemic data from Brazil, Colombia, and El Salvador. Parameter estimates yielded a basic reproduction number 0 = 2.055 (95% CI: 0.523-6.300), in which the percentage contribution of sexual transmission is 3.044% (95% CI: 0.123-45.73). Our sensitivity analyses indicate that 0 is most sensitive to the biting rate and mortality rate of mosquitoes while sexual transmission increases the risk of infection and epidemic size and prolongs the outbreak. Prevention and control efforts against ZIKV should target both the mosquito-borne and sexual transmission routes.

Prevention and Control of Zika as a Mosquito-Borne and Sexually Transmitted Disease: A Mathematical Modeling Analysis

NASA Astrophysics Data System (ADS)

Gao, Daozhou; Lou, Yijun; He, Daihai; Porco, Travis C.; Kuang, Yang; Chowell, Gerardo; Ruan, Shigui

2016-06-01

The ongoing Zika virus (ZIKV) epidemic in the Americas poses a major global public health emergency. While ZIKV is transmitted from human to human by bites of Aedes mosquitoes, recent evidence indicates that ZIKV can also be transmitted via sexual contact with cases of sexually transmitted ZIKV reported in Argentina, Canada, Chile, France, Italy, New Zealand, Peru, Portugal, and the USA. Yet, the role of sexual transmission on the spread and control of ZIKV infection is not well-understood. We introduce a mathematical model to investigate the impact of mosquito-borne and sexual transmission on the spread and control of ZIKV and calibrate the model to ZIKV epidemic data from Brazil, Colombia, and El Salvador. Parameter estimates yielded a basic reproduction number 0 = 2.055 (95% CI: 0.523-6.300), in which the percentage contribution of sexual transmission is 3.044% (95% CI: 0.123-45.73). Our sensitivity analyses indicate that 0 is most sensitive to the biting rate and mortality rate of mosquitoes while sexual transmission increases the risk of infection and epidemic size and prolongs the outbreak. Prevention and control efforts against ZIKV should target both the mosquito-borne and sexual transmission routes.

Prevention and Control of Zika as a Mosquito-Borne and Sexually Transmitted Disease: A Mathematical Modeling Analysis

PubMed Central

Gao, Daozhou; Lou, Yijun; He, Daihai; Porco, Travis C.; Kuang, Yang; Chowell, Gerardo; Ruan, Shigui

2016-01-01

The ongoing Zika virus (ZIKV) epidemic in the Americas poses a major global public health emergency. While ZIKV is transmitted from human to human by bites of Aedes mosquitoes, recent evidence indicates that ZIKV can also be transmitted via sexual contact with cases of sexually transmitted ZIKV reported in Argentina, Canada, Chile, France, Italy, New Zealand, Peru, Portugal, and the USA. Yet, the role of sexual transmission on the spread and control of ZIKV infection is not well-understood. We introduce a mathematical model to investigate the impact of mosquito-borne and sexual transmission on the spread and control of ZIKV and calibrate the model to ZIKV epidemic data from Brazil, Colombia, and El Salvador. Parameter estimates yielded a basic reproduction number 0 = 2.055 (95% CI: 0.523–6.300), in which the percentage contribution of sexual transmission is 3.044% (95% CI: 0.123–45.73). Our sensitivity analyses indicate that 0 is most sensitive to the biting rate and mortality rate of mosquitoes while sexual transmission increases the risk of infection and epidemic size and prolongs the outbreak. Prevention and control efforts against ZIKV should target both the mosquito-borne and sexual transmission routes. PMID:27312324

Fine-temporal forecasting of outbreak probability and severity: Ross River virus in Western Australia.

PubMed

Koolhof, I S; Bettiol, S; Carver, S

2017-10-01

Health warnings of mosquito-borne disease risk require forecasts that are accurate at fine-temporal resolutions (weekly scales); however, most forecasting is coarse (monthly). We use environmental and Ross River virus (RRV) surveillance to predict weekly outbreak probabilities and incidence spanning tropical, semi-arid, and Mediterranean regions of Western Australia (1991-2014). Hurdle and linear models were used to predict outbreak probabilities and incidence respectively, using time-lagged environmental variables. Forecast accuracy was assessed by model fit and cross-validation. Residual RRV notification data were also examined against mitigation expenditure for one site, Mandurah 2007-2014. Models were predictive of RRV activity, except at one site (Capel). Minimum temperature was an important predictor of RRV outbreaks and incidence at all predicted sites. Precipitation was more likely to cause outbreaks and greater incidence among tropical and semi-arid sites. While variable, mitigation expenditure coincided positively with increased RRV incidence (r 2 = 0·21). Our research demonstrates capacity to accurately predict mosquito-borne disease outbreaks and incidence at fine-temporal resolutions. We apply our findings, developing a user-friendly tool enabling managers to easily adopt this research to forecast region-specific RRV outbreaks and incidence. Approaches here may be of value to fine-scale forecasting of RRV in other areas of Australia, and other mosquito-borne diseases.

Modeling of electric field distribution in tissues during electroporation

PubMed Central

2013-01-01

Background Electroporation based therapies and treatments (e.g. electrochemotherapy, gene electrotransfer for gene therapy and DNA vaccination, tissue ablation with irreversible electroporation and transdermal drug delivery) require a precise prediction of the therapy or treatment outcome by a personalized treatment planning procedure. Numerical modeling of local electric field distribution within electroporated tissues has become an important tool in treatment planning procedure in both clinical and experimental settings. Recent studies have reported that the uncertainties in electrical properties (i.e. electric conductivity of the treated tissues and the rate of increase in electric conductivity due to electroporation) predefined in numerical models have large effect on electroporation based therapy and treatment effectiveness. The aim of our study was to investigate whether the increase in electric conductivity of tissues needs to be taken into account when modeling tissue response to the electroporation pulses and how it affects the local electric distribution within electroporated tissues. Methods We built 3D numerical models for single tissue (one type of tissue, e.g. liver) and composite tissue (several types of tissues, e.g. subcutaneous tumor). Our computer simulations were performed by using three different modeling approaches that are based on finite element method: inverse analysis, nonlinear parametric and sequential analysis. We compared linear (i.e. tissue conductivity is constant) model and non-linear (i.e. tissue conductivity is electric field dependent) model. By calculating goodness of fit measure we compared the results of our numerical simulations to the results of in vivo measurements. Results The results of our study show that the nonlinear models (i.e. tissue conductivity is electric field dependent: σ(E)) fit experimental data better than linear models (i.e. tissue conductivity is constant). This was found for both single tissue and composite tissue. Our results of electric field distribution modeling in linear model of composite tissue (i.e. in the subcutaneous tumor model that do not take into account the relationship σ(E)) showed that a very high electric field (above irreversible threshold value) was concentrated only in the stratum corneum while the target tumor tissue was not successfully treated. Furthermore, the calculated volume of the target tumor tissue exposed to the electric field above reversible threshold in the subcutaneous model was zero assuming constant conductivities of each tissue. Our results also show that the inverse analysis allows for identification of both baseline tissue conductivity (i.e. conductivity of non-electroporated tissue) and tissue conductivity vs. electric field (σ(E)) of electroporated tissue. Conclusion Our results of modeling of electric field distribution in tissues during electroporation show that the changes in electrical conductivity due to electroporation need to be taken into account when an electroporation based treatment is planned or investigated. We concluded that the model of electric field distribution that takes into account the increase in electric conductivity due to electroporation yields more precise prediction of successfully electroporated target tissue volume. The findings of our study can significantly contribute to the current development of individualized patient-specific electroporation based treatment planning. PMID:23433433

Cometary ion dynamics observed in the close vicinity of comet 67P/Churyumov-Gerasimenko during the intermediate activity period

NASA Astrophysics Data System (ADS)

Berčič, L.; Behar, E.; Nilsson, H.; Nicolaou, G.; Wieser, G. Stenberg; Wieser, M.; Goetz, C.

2018-06-01

Aims: Cometary ions are constantly produced in the coma, and once produced they are accelerated and eventually escape the coma. We describe and interpret the dynamics of the cometary ion flow, of an intermediate active comet, very close to the nucleus and in the terminator plane. Methods: We analysed in situ ion and magnetic field measurements, and characterise the velocity distribution functions (mostly using plasma moments). We propose a statistical approach over a period of one month. Results: On average, two populations were observed, separated in phase space. The motion of the first is governed by its interaction with the solar wind farther upstream, while the second one is accelerated in the inner coma and displays characteristics compatible with an ambipolar electric field. Both populations display a consistent anti-sunward velocity component. Conclusions: Cometary ions born in different regions of the coma are seen close to the nucleus of comet 67P/Churyumov-Gerasimenko with distinct motions governed in one case by the solar wind electric field and in the other case by the position relative to the nucleus. A consistent anti-sunward component is observed for all cometary ions. An asymmetry is found in the average cometary ion density in a solar wind electric field reference frame, with higher density in the negative (south) electric field hemisphere. There is no corresponding signature in the average magnetic field strength.

Medical expenditures associated with nonfatal occupational injuries among immigrant and U.S.-born workers

PubMed Central

2012-01-01

Background No national study has investigated whether immigrant workers are less likely than U.S.-workers to seek medical treatment after occupational injuries and whether the payment source differs between two groups. Methods Using the 2004–2009 Medical Expenditure Panel Survey (MEPS) data, we estimated the annual incidence rate of nonfatal occupational injuries per 100 workers. Logistic regression models were fitted to test whether injured immigrant workers were less likely than U.S.-born workers to seek professional medical treatment after occupational injuries. We also estimated the average mean medical expenditures per injured worker during the 2 year MEPS reference period using linear regression analysis, adjusting for gender, age, race, marital status, education, poverty level, and insurance. Types of service and sources of payment were compared between U.S.-born and immigrant workers. Results A total of 1,909 injured U.S.-born workers reported 2,176 occupational injury events and 508 injured immigrant workers reported 560 occupational injury events. The annual nonfatal incidence rate per 100 workers was 4.0% (95% CI: 3.8%-4.3%) for U.S.-born workers and 3.0% (95% CI: 2.6%-3.3%) for immigrant workers. Medical treatment was sought after 77.3% (95% CI: 75.1%-79.4%) of the occupational injuries suffered by U.S.-born workers and 75.6% (95% CI: 69.8%-80.7%) of the occupational injuries suffered by immigrant workers. The average medical expenditure per injured worker in the 2 year MEPS reference period was $2357 for the U.S.-born workers and $2,351 for immigrant workers (in 2009 U.S. dollars, P = 0.99). Workers’ compensation paid 57.0% (95% CI: 49.4%-63.6%) of the total expenditures for U.S.-born workers and 43.2% (95% CI: 33.0%-53.7%) for immigrant workers. U.S.-born workers paid 6.7% (95% CI: 5.5%-8.3%) and immigrant workers paid 7.1% (95% CI: 5.2%-9.6%) out-of-pocket. Conclusions Immigrant workers had a statistically significant lower incidence rate of nonfatal occupational injuries than U.S.-born workers. There was no significant difference in seeking medical treatment and in the mean expenditures per injured worker between the two groups. The proportion of total expenditures paid by workers’ compensation was smaller (marginally significant) for immigrant workers than for U.S.-born workers. PMID:22905938

A view to the future of natural gas and electricity: An integrated modeling approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cole, Wesley J.; Medlock, Kenneth B.; Jani, Aditya

This paper demonstrates the value of integrating two highly spatially resolved models: the Rice World Gas Trade Model (RWGTM) of the natural gas sector and the Regional Energy Deployment System (ReEDS) model of the U.S. electricity sector. The RWGTM passes electricity-sector natural gas prices to the ReEDS model, while the ReEDS model returns electricity-sector natural gas demand to the RWGTM. The two models successfully converge to a solution under reference scenario conditions. We present electricity-sector and natural gas sector evolution using the integrated models for this reference scenario. This paper demonstrates that the integrated models produced similar national-level results asmore » when running in a stand-alone form, but that regional and state-level results can vary considerably. As we highlight, these regional differences have potentially significant implications for electric sector planners especially in the wake of substantive policy changes for the sector (e.g., the Clean Power Plan).« less

A view to the future of natural gas and electricity: An integrated modeling approach

DOE PAGES

Cole, Wesley J.; Medlock, Kenneth B.; Jani, Aditya

2016-03-17

This paper demonstrates the value of integrating two highly spatially resolved models: the Rice World Gas Trade Model (RWGTM) of the natural gas sector and the Regional Energy Deployment System (ReEDS) model of the U.S. electricity sector. The RWGTM passes electricity-sector natural gas prices to the ReEDS model, while the ReEDS model returns electricity-sector natural gas demand to the RWGTM. The two models successfully converge to a solution under reference scenario conditions. We present electricity-sector and natural gas sector evolution using the integrated models for this reference scenario. This paper demonstrates that the integrated models produced similar national-level results asmore » when running in a stand-alone form, but that regional and state-level results can vary considerably. As we highlight, these regional differences have potentially significant implications for electric sector planners especially in the wake of substantive policy changes for the sector (e.g., the Clean Power Plan).« less

[Sudden cardiac death, a major scientific challenge].

PubMed

Haissaguerre, Michel; Hocini, Meleze; Sacher, Frédéric; Shah, Ashok

2010-06-01

Sudden death is responsible for 350,000 deaths each year in Europe, or 1000 deaths each day, equivalent to the combined mortality from the most lethal cancers (breast, lung and colorectal). Unfortunately, sudden death is widely considered to be "natural", being due to unknown but critical cardiac disorders leading to sudden arrest of cardiac activity. Awareness of its potential preventability is inadequate. Indeed, 80% of cases of sudden death are associated with extremely rapid heartbeats, an "electric tornado" called ventricular fibrillation, caused by ultrarapid firing of ectopic foci or chaotic wave propagation. This arrhythmia strikes like lightning Although it can be associated with myocardial infarction, most victims have structurally normal or slightly altered hearts. The cells which cause this ultrarapid firing originate from the Purkinje system, which constitutes just a fraction (2%) of total cardiac mass. This is borne out by the fact that the risk of fatal arrhythmic events can be reduced by focal thermoablation. What is most important is to identify subjects at risk of such events. It has been suggested that there exists an unidentified subclinical electrical disharmony, which converts into a tornado of ultimately fatal clinical events at a certain threshold level. High-resolution bioelectrical cardiac mapping, functional imaging, and treatment of electrical field disorders are major scientific challenges given their complexity, intraindividual dynamics and interindividual variability.

Joint 3D Inversion of ZTEM Airborne and Ground MT Data with Application to Geothermal Exploration

NASA Astrophysics Data System (ADS)

Wannamaker, P. E.; Maris, V.; Kordy, M. A.

2017-12-01

ZTEM is an airborne electromagnetic (EM) geophysical technique developed by Geotech Inc® where naturally propagated EM fields originating with regional and global lightning discharges (sferics) are measured as a means of inferring subsurface electrical resistivity structure. A helicopter-borne coil platform (bird) measuring the vertical component of magnetic (H) field variations along a flown profile is referenced to a pair of horizontal coils at a fixed location on the ground in order to estimate a tensor H-field transfer function. The ZTEM method is distinct from the traditional magnetotelluric (MT) method in that the electric (E) fields are not considered because of the technological challenge of measuring E-fields in the dielectric air medium. This can lend some non-uniqueness to ZTEM interpretation because a range of conductivity structures in the earth depending upon an assumed background earth resistivity model can fit ZTEM data to within tolerance. MT data do not suffer this particular problem, but they are cumbersome to acquire in their common need for land-based transport often in near-roadless areas and for laying out and digging the electrodes and H coils. The complementary nature of ZTEM and MT logistics and resolution has motivated development of schemes to acquire appropriate amounts of each data type in a single survey and to produce an earth image through joint inversion. In particular, consideration is given to surveys where only sparse MT soundings are needed to drastically reduce the non-uniqueness associated with background uncertainty while straining logistics minimally. Synthetic and field data are analysed using 2D and 3D finite element platforms developed for this purpose. Results to date suggest that indeed dense ZTEM surveys can provide detailed heterogeneous model images with large-scale averages constrained by a modest number of MT soundings. Further research is needed in determining the allowable degree of MT sparseness and the relative weighting of the two data sets in joint inversion.

Application of time-lapse ERT to Characterize Soil-Water-Disease Interactions of Citrus Orchard - Case Study

NASA Astrophysics Data System (ADS)

Peddinti, S. R.; Kbvn, D. P.; Ranjan, S.; Suradhaniwar, S.; J, P. A.; R M, G.

2015-12-01

Vidarbha region in Maharashtra, India (home for mandarin Orange) experience severe climatic uncertainties resulting in crop failure. Phytopthora are the soil-borne fungal species that accumulate in the presence of moisture, and attack the root / trunk system of Orange trees at any stage. A scientific understanding of soil-moisture-disease relations within the active root zone under different climatic, irrigation, and crop cycle conditions can help in practicing management activities for improved crop yield. In this study, we developed a protocol for performing 3-D time-lapse electrical resistivity tomography (ERT) at micro scale resolution to monitor the changes in resistivity distribution within the root zone of Orange trees. A total of 40 electrodes, forming a grid of 3.5 m x 2 m around each Orange tree were used in ERT survey with gradient and Wenner configurations. A laboratory test on un-disturbed soil samples of the region was performed to plot the variation of electrical conductivity with saturation. Curve fitting techniques were applied to get the modified Archie's model parameters. The calibrated model was further applied to generate the 3-D soil moisture profiles of the study area. The point estimates of soil moisture were validated using TDR probe measurements at 3 different depths (10, 20, and 40 cm) near to the root zone. In order to understand the effect of soil-water relations on plant-disease relations, we performed ERT analysis at two locations, one at healthy and other at Phytopthora affected Orange tree during the crop cycle, under dry and irrigated conditions. The degree to which an Orange tree is affected by Phytopthora under each condition is evaluated using 'grading scale' approach following visual inspection of the canopy features. Spatial-temporal distribution of moisture profiles is co-related with grading scales to comment on the effect of climatic and irrigation scenarios on the degree and intensity of crop disease caused by Phytopthora.

Exploring of Primate Models of Tick-Borne Flaviviruses Infection for Evaluation of Vaccines and Drugs Efficacy

PubMed Central

Pripuzova, Natalia S.; Gmyl, Larissa V.; Romanova, Lidiya Iu.; Tereshkina, Natalia V.; Rogova, Yulia V.; Terekhina, Liubov L.; Kozlovskaya, Liubov I.; Vorovitch, Mikhail F.; Grishina, Karina G.; Timofeev, Andrey V.; Karganova, Galina G.

2013-01-01

Tick-borne encephalitis virus (TBEV) is one of the most prevalent and medically important tick-borne arboviruses in Eurasia. There are overlapping foci of two flaviviruses: TBEV and Omsk hemorrhagic fever virus (OHFV) in Russia. Inactivated vaccines exist only against TBE. There are no antiviral drugs for treatment of both diseases. Optimal animal models are necessary to study efficacy of novel vaccines and treatment preparations against TBE and relative flaviviruses. The models for TBE and OHF using subcutaneous inoculation were tested in Cercopithecus aethiops and Macaca fascicularis monkeys with or without prior immunization with inactivated TBE vaccine. No visible clinical signs or severe pathomorphological lesions were observed in any monkey infected with TBEV or OHFV. C. aethiops challenged with OHFV showed massive hemolytic syndrome and thrombocytopenia. Infectious virus or viral RNA was revealed in visceral organs and CNS of C. aethiops infected with both viruses; however, viremia was low. Inactivated TBE vaccines induced high antibody titers against both viruses and expressed booster after challenge. The protective efficacy against TBE was shown by the absence of virus in spleen, lymph nodes and CNS of immunized animals after challenge. Despite the absence of expressed hemolytic syndrome in immunized C. aethiops TBE vaccine did not prevent the reproduction of OHFV in CNS and visceral organs. Subcutaneous inoculation of M. fascicularis with two TBEV strains led to a febrile disease with well expressed viremia, fever, and virus reproduction in spleen, lymph nodes and CNS. The optimal terms for estimation of the viral titers in CNS were defined as 8–16 days post infection. We characterized two animal models similar to humans in their susceptibility to tick-borne flaviviruses and found the most optimal scheme for evaluation of efficacy of preventive and therapeutic preparations. We also identified M. fascicularis to be more susceptible to TBEV than C. aethiops. PMID:23585873

Long-term impacts of battery electric vehicles on the German electricity system

NASA Astrophysics Data System (ADS)

Heinrichs, H. U.; Jochem, P.

2016-05-01

The emerging market for electric vehicles gives rise to an additional electricity demand. This new electricity demand will affect the electricity system. For quantifying those impacts a model-based approach, which covers long-term time horizons is necessary in order to consider the long lasting investment paths in electricity systems and the market development of electric mobility. Therefore, we apply a bottom-up electricity system model showing a detailed spatial resolution for different development paths of electric mobility in Germany until 2030. This model is based on a linear optimization which minimizes the discounted costs of the electricity system. We observe an increase of electricity exchange between countries and electricity generated by renewable energy sources. One major result turns out to be that electric vehicles can be integrated in the electricity system without increasing the system costs when a controlled (postponing) charging strategy for electric vehicles is applied. The impact on the power plant portfolio is insignificant. Another important side effect of electric vehicles is their substantial contribution to decreasing CO2 emissions of the German transport sector. Hence, electric mobility might be an integral part of a sustainable energy system of tomorrow.

The ten thousand Kims

NASA Astrophysics Data System (ADS)

Baek, Seung Ki; Minnhagen, Petter; Kim, Beom Jun

2011-07-01

In Korean culture, the names of family members are recorded in special family books. This makes it possible to follow the distribution of Korean family names far back in history. It is shown here that these name distributions are well described by a simple null model, the random group formation (RGF) model. This model makes it possible to predict how the name distributions change and these predictions are shown to be borne out. In particular, the RGF model predicts that for married women entering a collection of family books in a certain year, the occurrence of the most common family name 'Kim' should be directly proportional to the total number of married women with the same proportionality constant for all the years. This prediction is also borne out to a high degree. We speculate that it reflects some inherent social stability in the Korean culture. In addition, we obtain an estimate of the total population of the Korean culture down to the year 500 AD, based on the RGF model, and find about ten thousand Kims.

Essays on pricing electricity and electricity derivatives in deregulated markets

NASA Astrophysics Data System (ADS)

Popova, Julia

2008-10-01

This dissertation is composed of four essays on the behavior of wholesale electricity prices and their derivatives. The first essay provides an empirical model that takes into account the spatial features of a transmission network on the electricity market. The spatial structure of the transmission grid plays a key role in determining electricity prices, but it has not been incorporated into previous empirical models. The econometric model in this essay incorporates a simple representation of the transmission system into a spatial panel data model of electricity prices, and also accounts for the effect of dynamic transmission system constraints on electricity market integration. Empirical results using PJM data confirm the existence of spatial patterns in electricity prices and show that spatial correlation diminishes as transmission lines become more congested. The second essay develops and empirically tests a model of the influence of natural gas storage inventories on the electricity forward premium. I link a model of the effect of gas storage constraints on the higher moments of the distribution of electricity prices to a model of the effect of those moments on the forward premium. Empirical results using PJM data support the model's predictions that gas storage inventories sharply reduce the electricity forward premium when demand for electricity is high and space-heating demand for gas is low. The third essay examines the efficiency of PJM electricity markets. A market is efficient if prices reflect all relevant information, so that prices follow a random walk. The hypothesis of random walk is examined using empirical tests, including the Portmanteau, Augmented Dickey-Fuller, KPSS, and multiple variance ratio tests. The results are mixed though evidence of some level of market efficiency is found. The last essay investigates the possibility that previous researchers have drawn spurious conclusions based on classical unit root tests incorrectly applied to wholesale electricity prices. It is well known that electricity prices exhibit both cyclicity and high volatility which varies through time. Results indicate that heterogeneity in unconditional variance---which is not detected by classical unit root tests---may contribute to the appearance of non-stationarity.

INTEGRATED PROBABILISTIC AND DETERMINISTIC MODELING TECHNIQUES IN ESTIMATING EXPOSURE TO WATER-BORNE CONTAMINANTS: PART 2 PHARMACOKINETIC MODELING

EPA Science Inventory

The Total Exposure Model (TEM) uses deterministic and stochastic methods to estimate the exposure of a person performing daily activities of eating, drinking, showering, and bathing. There were 250 time histories generated, by subject with activities, for the three exposure ro...

The development of a model and decision support system to use in forecasting truck freight flow in the continental United States

DOT National Transportation Integrated Search

2001-01-01

This research develops a regression-based model for forecasting truck borne freight in the continental United States. This model is capable of predicting freight commodity flow information via trucks to assist transportation planners who wish to unde...

A gauged finite-element potential formulation for accurate inductive and galvanic modelling of 3-D electromagnetic problems

NASA Astrophysics Data System (ADS)

Ansari, S. M.; Farquharson, C. G.; MacLachlan, S. P.

2017-07-01

In this paper, a new finite-element solution to the potential formulation of the geophysical electromagnetic (EM) problem that explicitly implements the Coulomb gauge, and that accurately computes the potentials and hence inductive and galvanic components, is proposed. The modelling scheme is based on using unstructured tetrahedral meshes for domain subdivision, which enables both realistic Earth models of complex geometries to be considered and efficient spatially variable refinement of the mesh to be done. For the finite-element discretization edge and nodal elements are used for approximating the vector and scalar potentials respectively. The issue of non-unique, incorrect potentials from the numerical solution of the usual incomplete-gauged potential system is demonstrated for a benchmark model from the literature that uses an electric-type EM source, through investigating the interface continuity conditions for both the normal and tangential components of the potential vectors, and by showing inconsistent results obtained from iterative and direct linear equation solvers. By explicitly introducing the Coulomb gauge condition as an extra equation, and by augmenting the Helmholtz equation with the gradient of a Lagrange multiplier, an explicitly gauged system for the potential formulation is formed. The solution to the discretized form of this system is validated for the above-mentioned example and for another classic example that uses a magnetic EM source. In order to stabilize the iterative solution of the gauged system, a block diagonal pre-conditioning scheme that is based upon the Schur complement of the potential system is used. For all examples, both the iterative and direct solvers produce the same responses for the potentials, demonstrating the uniqueness of the numerical solution for the potentials and fixing the problems with the interface conditions between cells observed for the incomplete-gauged system. These solutions of the gauged system also produce the physically anticipated behaviours for the inductive and galvanic components of the electric field. For a realistic geophysical scenario, the gauged scheme is also used to synthesize the magnetic field response of a model of the Ovoid ore deposit at Voisey's Bay, Labrador, Canada. The results are in good agreement with the helicopter-borne EM data from the real survey, and the inductive and galvanic parts of the current density show expected behaviours.

An Exploration of Differences in Sleep Characteristics between Mexico-born US Immigrants and Other Americans to Address the Hispanic Paradox

PubMed Central

Seicean, Sinziana; Neuhauser, Duncan; Strohl, Kingman; Redline, Susan

2011-01-01

Study Objectives: Decreased sleep duration and quality are associated with poor health. Given that Mexico-born US immigrants (MI) often have favorable health status relative to the general US population (USALL), we tested the hypothesis that MI have better sleep as compared to USALL and to Mexican-Americans (MA) born in the US Research Design and Methods: Cross-sectional analysis of a stratified multistage probability sample of 18 years and older civilian non-institutionalized USALL enrolled in NHANES during 2005-2006. Age-adjusted population prevalence rates and adjusted odd ratios of short habitual sleep time (SHST) and insomnia were calculated using weighted analyses. Setting: Computer assisted personal bilingual (English/Spanish) interviews in the participants' home using a sleep questionnaire. Participants: 5160 USALL participants, including 1046 MA, of whom 620 were MI. Results: In logistic regression models unadjusted and adjusted for socioeconomic characteristics, health related behavior risk factors, health status, and depression, MI status was significantly associated with lower odds of SHST (OR = 0.7, 95%CI [0.6-0.9]), insomnia (OR = 0.3, 95%CI [0.2-0.5]), and sleep-associated functional impairments (OR = 0.4, 95%CI [0.2-0.8]). In MA males, MI status was associated with reduced odds of SHST < 7 h/weeknight and insomnia symptoms. Cultural changes measured by increased levels of English compared to Spanish language spoken at home were associated with an increased risk of poor sleep in MA men in univariate models, and may partially explain better sleep in MI men compared to their US-born counterparts. Conclusion: Compared to the general US poplulation, Mexican-born US immigrants have more favorable sleep, possibly contributing to their lower reported risk of diabetes, hypertension, CVD, and all-cause mortality (the “Hispanic Paradox”). Citation: Seicean S; Neuhauser D; Strohl K; Redline S. An exploration of differences in sleep characteristics between Mexico-born US immigrants and other Americans to address the Hispanic paradox. SLEEP 2011;34(8):1021-1031. PMID:21804664

Electricity Consumption in the Industrial Sector of Jordan: Application of Multivariate Linear Regression and Adaptive Neuro-Fuzzy Techniques

NASA Astrophysics Data System (ADS)

Samhouri, M.; Al-Ghandoor, A.; Fouad, R. H.

2009-08-01

In this study two techniques, for modeling electricity consumption of the Jordanian industrial sector, are presented: (i) multivariate linear regression and (ii) neuro-fuzzy models. Electricity consumption is modeled as function of different variables such as number of establishments, number of employees, electricity tariff, prevailing fuel prices, production outputs, capacity utilizations, and structural effects. It was found that industrial production and capacity utilization are the most important variables that have significant effect on future electrical power demand. The results showed that both the multivariate linear regression and neuro-fuzzy models are generally comparable and can be used adequately to simulate industrial electricity consumption. However, comparison that is based on the square root average squared error of data suggests that the neuro-fuzzy model performs slightly better for future prediction of electricity consumption than the multivariate linear regression model. Such results are in full agreement with similar work, using different methods, for other countries.

Host surveys, ixodid tick biology and transmission scenarios as related to the tick-borne pathogen, Ehrlichia canis

PubMed Central

Stich, R. W.; Schaefer, John J.; Bremer, William G.; Needham, Glen R.; Jittapalapong, Sathaporn

2008-01-01

The ehrlichioses have been subject to increasing interest from veterinary and public health perspectives, but experimental studies of these diseases and their etiologic agents can be challenging. Ehrlichia canis, the primary etiologic agent of canine monocytic ehrlichiosis, is relatively well characterized and offers unique advantages and opportunities to study interactions between a monocytotropic pathogen and both its vertebrate and invertebrate hosts. Historically, advances in tick-borne disease control strategies have typically followed explication of tick-pathogen-vertebrate interactions, thus it is reasonable to expect novel, more sustainable approaches to control of these diseases as the transmission of their associated infections are investigated at the molecular through ecological levels. Better understanding of the interactions between E. canis and its canine and tick hosts would also elucidate similar interactions for other Ehrlichia species as well as the potential roles of canine sentinels, reservoirs and models of tick-borne zoonoses. This article summarizes natural exposure studies and experimental investigations of E. canis in the context of what is understood about biological vectors of tick-borne Anaplasmataceae. PMID:18963493

Direct and mediated effects of nativity and other indicators of acculturation on Hispanic mothers' use of physical aggression.

PubMed

Altschul, Inna; Lee, Shawna J

2011-11-01

This study used data from 845 foreign-born (n = 328) and native-U.S. born (n = 517) Hispanic mothers who participated in the Fragile Families and Child Wellbeing Study (FFCWS) to examine four indicators of acculturation--nativity, years lived in the United States, religious attendance, and endorsement of traditional gender norms--as predictors of maternal physical aggression directed toward young children. The authors also examined whether psychosocial risk factors associated with child maltreatment and acculturation--maternal alcohol use, depression, parenting stress, and intimate partner aggression and violence--mediate relationships between acculturation and maternal aggression. Foreign-born Hispanic mothers had significantly lower rates of physical aggression than native-born Hispanic mothers. In path modeling results, U.S. nativity, along with maternal alcohol use, parenting stress, and child aggressive behavior, emerged as the strongest risk factors for maternal physical aggression. Among the four acculturation indicators, only foreign birth was directly associated with lower maternal aggression. Study findings suggest immigrant status is a unique protective factor that contributes to lower levels of physical aggression among Hispanic mothers.

First-born siblings show better second language skills than later born siblings

PubMed Central

Keller, Karin; Troesch, Larissa M.; Grob, Alexander

2015-01-01

We examined the extent to which three sibling structure variables number of siblings, birth order, and presence of an older sibling at school age are linked to the second language skills of bilingual children. The research questions were tested using an ethnically heterogeneous sample of 1209 bilingual children with German as a second language. Controlling for children’s age, sex, nationality, number of children’s books at home, family language and parental German language skills, hierarchical regression analyses showed an inverse relationship between the number of siblings and second language skills: the more siblings a child had, the lower was his/her second language proficiency. This relationship was mediated by attendance in early education institutions. Moreover, first-born siblings showed better second language skills than later born siblings. The current study revealed that the resource dilution model, i.e., the decrease in resources for every additional sibling, holds for second language acquisition. Moreover, the results indicate that bilingual children from families with several children benefit from access to early education institutions. PMID:26089806

Physical and mental health disparities among young children of Asian immigrants.

PubMed

Huang, Keng-Yen; Calzada, Esther; Cheng, Sabrina; Brotman, Laurie Miller

2012-02-01

To examine physical and mental health functioning among Asian-American children of US-born and immigrant parents. We used data from the Early Childhood Longitudinal Study-Kindergarten Class of 1998-1999 base-year public data file. The sample was restricted to 7726 Asian and US-born white children. Asian subgroups were created based on parents' country of birth. Child physical and mental health was assessed based on multiple sources of data and measures. Analyses included multivariate linear and logistic regression. After adjusting for demographic and contextual differences, disparities were found for physical and mental health indicators. Children of foreign-born Asian families (from east, southeast, and south Asia) were at greater risk for poor physical health, internalizing problems, and inadequate interpersonal relationships compared with children of US-born white families. There is little support for the "model minority" myth with regard to physical and mental health. Evidence of physical and mental health disparities among young Asian-American children and differing risk based on region of origin of immigrant parents suggests the need for culturally informed prevention efforts during early childhood. Copyright © 2012 Mosby, Inc. All rights reserved.

Potential-Energy Surfaces, the Born-Oppenheimer Approximations, and the Franck-Condon Principle: Back to the Roots.

PubMed

Mustroph, Heinz

2016-09-05

The concept of a potential-energy surface (PES) is central to our understanding of spectroscopy, photochemistry, and chemical kinetics. However, the terminology used in connection with the basic approximations is variously, and somewhat confusingly, represented with such phrases as "adiabatic", "Born-Oppenheimer", or "Born-Oppenheimer adiabatic" approximation. Concerning the closely relevant and important Franck-Condon principle (FCP), the IUPAC definition differentiates between a classical and quantum mechanical formulation. Consequently, in many publications we find terms such as "Franck-Condon (excited) state", or a vertical transition to the "Franck-Condon point" with the "Franck-Condon geometry" that relaxes to the excited-state equilibrium geometry. The Born-Oppenheimer approximation and the "classical" model of the Franck-Condon principle are typical examples of misused terms and lax interpretations of the original theories. In this essay, we revisit the original publications of pioneers of the PES concept and the FCP to help stimulate a lively discussion and clearer thinking around these important concepts. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Generational differences in the reporting of tinnitus.

PubMed

Nondahl, David M; Cruickshanks, Karen J; Huang, Guan-Hua; Klein, Barbara E K; Klein, Ronald; Tweed, Ted S; Zhan, Weihai

2012-01-01

Recent research suggests that hearing impairment is declining among older adults compared with earlier generations of the same age. Tinnitus is often associated with hearing impairment, so one might hypothesize that the prevalence of tinnitus is declining in a similar manner. The purpose of this study was to use multigenerational data with repeated measures to determine whether the prevalence of tinnitus is declining among more recent generations. Using data from the Epidemiology of Hearing Loss Study (1993-1995, 1998-2000, 2003-2005, and 2009-2010) and the Beaver Dam Offspring Study (2005-2008), the authors examined birth cohort patterns in the report of tinnitus for adults aged 45 years and older (n =12,689 observations from 5764 participants). Participants were classified as having tinnitus if they reported tinnitus in the past year of at least moderate severity or that caused difficulty falling asleep. A low-frequency (500, 1000, and 2000 Hz) and high-frequency (3000, 4000, 6000, and 8000 Hz) pure tone average from the worse ear was used to summarize hearing status. Other potential risk factors for tinnitus were also explored to determine if changes in the prevalence of these factors over time could explain any observed birth cohort differences in the prevalence of tinnitus. These included the following: education, history of head injury, history of doctor-diagnosed ear infections, history of cardiovascular disease (myocardial infarction, stroke, or angina), current noisy job, longest-held job, target shooting in the past year, number of concerts ever attended, alcohol use in the past year, doctor diagnosis of arthritis, current aspirin use, regular exercise, and consulting with a physician in the past year about any hearing/ear problem. Birth cohort effects were modeled with alternating logistic regression models which use generalized estimating equations to adjust for correlation among repeated measurements over time that are nested within families. The report of tinnitus tended to increase with more recent birth cohorts compared with earlier birth cohorts. For example, at ages 55 to 59 years, 7.6% of participants born between 1935 and 1939 reported tinnitus, compared with 11.0% of those born in 1940 to 1944, 13.6% of those born between 1945 and 1949, and 17.5% of those born between 1950 and 1954. Similarly, at ages 65 to 69 years, 7.9% of participants born between 1925 and 1929 reported tinnitus, compared with 10.0% of those born between 1930 and 1934, 11.9% of those born between 1935 and 1939, and 13.7% of those born between 1940 and 1944. Final alternating logistic regression model results indicated that, on average, after adjusting for age and other factors, participants in a given generation were significantly more likely to report tinnitus than participants from a generation 20 years earlier (odds ratio = 1.78, 95% confidence interval = 1.44, 2.21). Increased reports of tinnitus may reflect increased prevalence of symptoms, increased awareness of symptoms, or higher health expectations among more recent generations of adults. Regardless of the reasons, the increasing prevalence of tinnitus suggests that health care providers may see an increased number of patients bothered by this common but little understood symptom.

Twin-singleton differences in intelligence: a register-based birth cohort study of Norwegian males.

PubMed

Eriksen, Willy; Sundet, Jon M; Tambs, Kristian

2012-10-01

The aim was to determine the difference in intelligence between singletons and twins in young adulthood. Data from the Medical Birth Register of Norway were linked with register data from the Norwegian National Conscript Service. The study base consisted of data on the 445,463 males who were born alive in either single or twin births in Norway during 1967-1984 and who were examined at the time of the mandatory military conscription (age 18-20). Within this study base, there were data on 1,653 sibships of full brothers that included at least one man born in single birth and at least one man born in twin birth (4,307 persons, including 2,378 twins and 1,929 singletons). The intelligence scores of the singletons were 11% (95% confidence interval [CI]: 9-14%) of a standard deviation higher than those of the twins, after adjustment for birth year, birth order, parental ages at delivery, parental education levels, and other factors. The adjusted within-family difference was also 11% (95 % CI: 6-16%) of a standard deviation, indicating that unmeasured factors shared by siblings (e.g., maternal body height) have not influenced the estimate in important ways. When gestational age at birth was added to the model, the estimate for the difference in intelligence score was approximately the same. Including birth weight in the model strongly reduced the estimate. In conclusion, twins born in Norway during 1967-1984 had slightly lower intelligence in early adulthood compared with the singletons.

Adaptation and Evaluation of a Multi-Criteria Decision Analysis Model for Lyme Disease Prevention

PubMed Central

Aenishaenslin, Cécile; Gern, Lise; Michel, Pascal; Ravel, André; Hongoh, Valérie; Waaub, Jean-Philippe; Milord, François; Bélanger, Denise

2015-01-01

Designing preventive programs relevant to vector-borne diseases such as Lyme disease (LD) can be complex given the need to include multiple issues and perspectives into prioritizing public health actions. A multi-criteria decision aid (MCDA) model was previously used to rank interventions for LD prevention in Quebec, Canada, where the disease is emerging. The aim of the current study was to adapt and evaluate the decision model constructed in Quebec under a different epidemiological context, in Switzerland, where LD has been endemic for the last thirty years. The model adaptation was undertaken with a group of Swiss stakeholders using a participatory approach. The PROMETHEE method was used for multi-criteria analysis. Key elements and results of the MCDA model are described and contrasted with the Quebec model. All criteria and most interventions of the MCDA model developed for LD prevention in Quebec were directly transferable to the Swiss context. Four new decision criteria were added, and the list of proposed interventions was modified. Based on the overall group ranking, interventions targeting human populations were prioritized in the Swiss model, with the top ranked action being the implementation of a large communication campaign. The addition of criteria did not significantly alter the intervention rankings, but increased the capacity of the model to discriminate between highest and lowest ranked interventions. The current study suggests that beyond the specificity of the MCDA models developed for Quebec and Switzerland, their general structure captures the fundamental and common issues that characterize the complexity of vector-borne disease prevention. These results should encourage public health organizations to adapt, use and share MCDA models as an effective and functional approach to enable the integration of multiple perspectives and considerations in the prevention and control of complex public health issues such as Lyme disease or other vector-borne and zoonotic diseases. PMID:26295344

Adaptation and Evaluation of a Multi-Criteria Decision Analysis Model for Lyme Disease Prevention.

PubMed

Aenishaenslin, Cécile; Gern, Lise; Michel, Pascal; Ravel, André; Hongoh, Valérie; Waaub, Jean-Philippe; Milord, François; Bélanger, Denise

2015-01-01

Designing preventive programs relevant to vector-borne diseases such as Lyme disease (LD) can be complex given the need to include multiple issues and perspectives into prioritizing public health actions. A multi-criteria decision aid (MCDA) model was previously used to rank interventions for LD prevention in Quebec, Canada, where the disease is emerging. The aim of the current study was to adapt and evaluate the decision model constructed in Quebec under a different epidemiological context, in Switzerland, where LD has been endemic for the last thirty years. The model adaptation was undertaken with a group of Swiss stakeholders using a participatory approach. The PROMETHEE method was used for multi-criteria analysis. Key elements and results of the MCDA model are described and contrasted with the Quebec model. All criteria and most interventions of the MCDA model developed for LD prevention in Quebec were directly transferable to the Swiss context. Four new decision criteria were added, and the list of proposed interventions was modified. Based on the overall group ranking, interventions targeting human populations were prioritized in the Swiss model, with the top ranked action being the implementation of a large communication campaign. The addition of criteria did not significantly alter the intervention rankings, but increased the capacity of the model to discriminate between highest and lowest ranked interventions. The current study suggests that beyond the specificity of the MCDA models developed for Quebec and Switzerland, their general structure captures the fundamental and common issues that characterize the complexity of vector-borne disease prevention. These results should encourage public health organizations to adapt, use and share MCDA models as an effective and functional approach to enable the integration of multiple perspectives and considerations in the prevention and control of complex public health issues such as Lyme disease or other vector-borne and zoonotic diseases.

Impedance analysis of cultured cells: a mean-field electrical response model for electric cell-substrate impedance sensing technique.

PubMed

Urdapilleta, E; Bellotti, M; Bonetto, F J

2006-10-01

In this paper we present a model to describe the electrical properties of a confluent cell monolayer cultured on gold microelectrodes to be used with electric cell-substrate impedance sensing technique. This model was developed from microscopic considerations (distributed effects), and by assuming that the monolayer is an element with mean electrical characteristics (specific lumped parameters). No assumptions were made about cell morphology. The model has only three adjustable parameters. This model and other models currently used for data analysis are compared with data we obtained from electrical measurements of confluent monolayers of Madin-Darby Canine Kidney cells. One important parameter is the cell-substrate height and we found that estimates of this magnitude strongly differ depending on the model used for the analysis. We analyze the origin of the discrepancies, concluding that the estimates from the different models can be considered as limits for the true value of the cell-substrate height.

Processing on weak electric signals by the autoregressive model

NASA Astrophysics Data System (ADS)

Ding, Jinli; Zhao, Jiayin; Wang, Lanzhou; Li, Qiao

2008-10-01

A model of the autoregressive model of weak electric signals in two plants was set up for the first time. The result of the AR model to forecast 10 values of the weak electric signals is well. It will construct a standard set of the AR model coefficient of the plant electric signal and the environmental factor, and can be used as the preferences for the intelligent autocontrol system based on the adaptive characteristic of plants to achieve the energy saving on agricultural productions.

Electrical Resistance Based Damage Modeling of Multifunctional Carbon Fiber Reinforced Polymer Matrix Composites

NASA Astrophysics Data System (ADS)

Hart, Robert James

In the current thesis, the 4-probe electrical resistance of carbon fiber-reinforced polymer (CFRP) composites is utilized as a metric for sensing low-velocity impact damage. A robust method has been developed for recovering the directionally dependent electrical resistivities using an experimental line-type 4-probe resistance method. Next, the concept of effective conducting thickness was uniquely applied in the development of a brand new point-type 4-probe method for applications with electrically anisotropic materials. An extensive experimental study was completed to characterize the 4-probe electrical resistance of CFRP specimens using both the traditional line-type and new point-type methods. Leveraging the concept of effective conducting thickness, a novel method was developed for building 4-probe electrical finite element (FE) models in COMSOL. The electrical models were validated against experimental resistance measurements and the FE models demonstrated predictive capabilities when applied to CFRP specimens with varying thickness and layup. These new models demonstrated a significant improvement in accuracy compared to previous literature and could provide a framework for future advancements in FE modeling of electrically anisotropic materials. FE models were then developed in ABAQUS for evaluating the influence of prescribed localized damage on the 4-probe resistance. Experimental data was compiled on the impact response of various CFRP laminates, and was used in the development of quasi- static FE models for predicting presence of impact-induced delamination. The simulation-based delamination predictions were then integrated into the electrical FE models for the purpose of studying the influence of realistic damage patterns on electrical resistance. When the size of the delamination damage was moderate compared to the electrode spacing, the electrical resistance increased by less than 1% due to the delamination damage. However, for a specimen with large delamination extending beyond the electrode locations, the oblique resistance increased by 30%. This result suggests that for damage sensing applications, the spacing of electrodes relative to the size of the delamination is important. Finally CT image data was used to model 3-D void distributions and the electrical response of such specimens were compared to models with no voids. As the void content increased, the electrical resistance increased non-linearly. The relationship between void content and electrical resistance was attributed to a combination of three factors: (i) size and shape, (ii) orientation, and (iii) distribution of voids. As a whole, the current thesis provides a comprehensive framework for developing predictive, resistance-based damage sensing models for CFRP laminates of various layup and thickness.

An Undergraduate Student Instrumentation Project (USIP) to Develop New Instrument Technology to Study the Auroral Ionosphere and Stratospheric Ozone Layer Using Ultralight Balloon Payloads

NASA Astrophysics Data System (ADS)

Nowling, M.; Ahmad, H.; Gamblin, R.; Guala, D.; Hermosillo, D.; Pina, M.; Marrero, E.; Canales, D. R. J.; Cao, J.; Ehteshami, A.; Bering, E. A., III; Lefer, B. L.; Dunbar, B.; Bias, C.; Shahid, S.

2015-12-01

This project is currently engaging twelve undergraduate students in the process of developing new technology and instrumentation for use in balloon borne geospace investigations in the auroral zone. Motivation stems from advances in microelectronics and consumer electronic technology. Given the technological innovations over the past 20 years it now possible to develop new instrumentation to study the auroral ionosphere and stratospheric ozone layer using ultralight balloon payloads for less than 6lbs and $3K per payload. The University of Houston Undergraduate Student Instrumentation Project (USIP) team has built ten such payloads for launch using 1500 gm latex weather balloons deployed in Houston, TX, Fairbanks, AK, and as well as zero pressure balloons launched from northern Sweden. The latex balloon project will collect vertical profiles of wind velocity, temperature, electrical conductivity, ozone, and odd nitrogen. This instrument payload will also produce profiles of pressure, electric field, and air-earth electric current. The zero pressure balloons will obtain a suite of geophysical measurements including: DC electric field, electric field and magnetic flux, optical imaging, total electron content of ionosphere via dual-channel GPS, X-ray detection, and infrared/UV spectroscopy. Students flew payloads with different combinations of these instruments to determine which packages are successful. Data collected by these instruments will be useful in understanding the nature of electrodynamic coupling in the upper atmosphere and how the global earth system is changing. Twelve out of the launched fifteen payloads were successfully launched and recovered. Results and best practices learned from lab tests and initial Houston test flights will be discussed.

Electrodynamics of the stratosphere using 5000 m3 superpressure balloons

NASA Astrophysics Data System (ADS)

Holzworth, R. H.

Recently the U. S. National Science Foundation and NASA have begun support of a long duration balloon-borne experiment to study electrical properties of the upper atmosphere. This research project titled EMA (Electrodynamics of the Middle Atmopshere) involves the design of a microprocessor controlled payload and the launch of up to eight small superpressure balloons during 1982 through early 1984. The primary payload instrument will measure the vector electric field from DC to 10 kHz and the payloads will include instruments to measure local ionization, electrical conductivity, magnetic field, pressure and temperature fluctuations and to record optical lightning. Measurement of these parameters in the stratosphere from a few balloons simultaneously for periods extending over a few solar rotations will enable us to study (1) electrical coupling between the atmosphere and magnetosphere, (2) global current systems, (3) global response to solar flares and magnetospheric storms and many other outstanding problems. In order to obtain long duration flights, it is necessary to fly in the southern hemisphere where the balloons are expected to circle the globe dozens of times in their lifetimes. Thus the balloons will be out of direct communication with any one ground station most of the time so the telemetry will be relayed via satellite. This severely limits the data rates resulting in the need for on-board data processing. This is accomplished through the use of dual microcomputers for data analysis and for telemetry formatting. This talk will concentrate on a description of our payload design as driven by the scientific requirements. Examples of the types of electric field signatures we expect to be able to distinguish will also be presented.

Convection and electrodynamic signatures in the vicinity of a Sun-aligned arc: Results from the Polar Acceleration Regions and Convection Study (Polar ARCS)

NASA Technical Reports Server (NTRS)

Weiss, L. A.; Weber, E. J.; Reiff, P. H.; Sharber, J. R.; Winningham, J. D.; Primdahl, F.; Mikkelsen, I. S.; Seifring, C.; Wescott, Eugene M.

1994-01-01

An experimental campaign designed to study high-latitude auroral arcs was conducted in Sondre Stromfjord, Greenland, on February 26, 1987. The Polar Acceleration Regions and Convection Study (Polar ARCS) consisted of a coordinated set of ground-based, airborne, and sounding rocket measurements of a weak, sun-aligned arc system within the duskside polar cap. A rocket-borne barium release experiment, two DMSP satellite overflights, all-sky photography, and incoherent scatter radar measurements provided information on the large-scale plasma convection over the polar cap region while a second rocket instrumented with a DC magnetometer, Langmuir and electric field probes, and an electron spectrometer provided measurements of small-scale electrodynamics. The large-scale data indicate that small, sun-aligned precipitation events formed within a region of antisunward convection between the duskside auroral oval and a large sun-aligned arc further poleward. This convection signature, used to assess the relationship of the sun-aligned arc to the large-scale magnetospheric configuration, is found to be consistent with either a model in which the arc formed on open field lines on the dusk side of a bifurcated polar cap or on closed field lines threading an expanded low-latitude boundary layer, but not a model in which the polar cap arc field lines map to an expanded plasma sheet. The antisunward convection signature may also be explained by a model in which the polar cap arc formed on long field lines recently reconnected through a highly skewed plasma sheet. The small-scale measurements indicate the rocket passed through three narrow (less than 20 km) regions of low-energy (less than 100 eV) electron precipitation in which the electric and magnetic field perturbations were well correlated. These precipitation events are shown to be associated with regions of downward Poynting flux and small-scale upward and downward field-aligned currents of 1-2 micro-A/sq m. The paired field-aligned currents are associated with velocity shears (higher and lower speed streams) embedded in the region of antisunward flow.