Hanford Site protective isolation surface barrier: Taking research and development to engineered application

International Nuclear Information System (INIS)

Myers, D.R.; Wing, N.R.

1994-01-01

The development of the Protective Isolation Surface Barrier has been an ongoing program since 1985. This development effort has focused on several technical areas. These technical areas include water infiltration, biointrusion, human intrusion, erosion/deposition, physical stability, barrier materials, computer modeling, long-term climate effects, natural analogs, and barrier design. This paper briefly reviews the results of the research and development in the technical areas and then explains how the results of this work have influenced the design features of the prototype barrier. A good example of this is to explain how the type and depth of the soil layer used in the barrier is related to water infiltration, biointrusion, modeling, climate, analogs, and barrier materials. Another good example is to explain the relationship of the barrier sideslopes (basalt riprap and native soil) with human intrusion, biointrusion, barrier materials, and barrier design. In general, the design features of the prototype barrier will be explained in terms of the results of the testing and development program. After the basis for prototype barrier design has been established, the paper will close by reviewing the construction of the prototype barrier, sharing the lessons learned during construction, and explaining the ongoing testing and monitoring program which will determine the success or failure of this barrier concept and the need for additional design modifications

Field Lysimeter Test Facility for protective barriers: Experimental plan

International Nuclear Information System (INIS)

Kirkham, R.R.; Gee, G.W.; Downs, J.L.

1987-12-01

This document was first written in October 1986 and has been used to guide the design of the Field Lysimeter Test Facility (FLTF) and to promote discussions between research and engineering staff regarding the selection of barrier treatments for inclusion in the FLTF. The construction of the lysimeter facility was completed June 28, 1987. This document describes the facility, the treatments placed in each lysimeter, types of measurements made in each lysimeter, and a brief discussion of project activities related to quality assurance, safety, and funding requirements. The treatment description and figures have been updated to reflect the lysimeter facility as constructed. 12 refs., 6 figs., 5 tabs

The Influence of Visibility Conditions in Horizontal Road Curves on the Efficiency of Noise Protection Barriers

Directory of Open Access Journals (Sweden)

Džambas Tamara

2013-12-01

Full Text Available Ensuring sufficient visibility on planned roads by sight distance testing is an integral part of every project, but problems with visibility can emerge when noise barriers are erected on existing roads. Namely, in order to provide sufficient noise protection, high noise barriers are often placed at minimum distance from the carriageway edge, and additional visibility testing in most cases is not carried out.

Factors for Consideration in an Open-Flame Test for Assessing Fire Blocking Performance of Barrier Fabrics

Directory of Open Access Journals (Sweden)

Shonali Nazaré

2016-09-01

Full Text Available The main objective of the work reported here is to assess factors that could affect the outcome of a proposed open flame test for barrier fabrics (BF-open flame test. The BF-open flame test characterizes barrier effectiveness by monitoring the ignition of a flexible polyurethane foam (FPUF layer placed in contact with the upper side of the barrier fabric, exposed to a burner flame from below. Particular attention is given to the factors that influence the ignitibility of the FPUF, including thermal resistance, permeability, and structural integrity of the barrier fabrics (BFs. A number of barrier fabrics, displaying a wide range of the properties, are tested with the BF-open flame test. Visual observations of the FPUF burning behavior and BF char patterns, in addition to heat flux measurements on the unexposed side of the barrier fabrics, are used to assess the protective performance of the BF specimen under the open flame test conditions. The temperature and heat transfer measurements on the unexposed side of the BF and subsequent ranking of BFs for their thermal protective performance suggest that the BF-open flame test does not differentiate barrier fabrics based on their heat transfer properties. A similar conclusion is reached with regard to BF permeability characterized at room temperature. However, the outcome of this BF-open flame test is found to be heavily influenced by the structural integrity of thermally degraded BF. The BF-open flame test, in its current form, only ignited FPUF when structural failure of the barrier was observed.

Biointrusion test plan for the Permanent Isolation Surface Barrier Prototype

International Nuclear Information System (INIS)

Link, S.O.; Cadwell, L.L.; Brandt, C.A.; Downs, J.L.; Rossi, R.E.; Gee, G.W.

1994-04-01

This document provides a testing and monitoring plan for the biological component of the prototype barrier slated for construction at the Hanford Site. The prototype barrier is an aboveground structure engineered to demonstrate the basic features of an earthen cover system. It is designed to permanently isolate waste from the biosphere. The features of the barrier include multiple layers of soil and rock materials and a low-permeability asphalt sublayer. The surface of the barrier consists of silt loam soil, covered with plants. The barrier sides are reinforced with rock or coarse earthen-fill to protect against wind and water erosion. The sublayers inhibit plant and animal intrusion and percolation of water. A series of tests will be conducted on the prototype barrier over the next several years to evaluate barrier performance under extreme climatic conditions. Plants and animals will play a significant role in the hydrologic and water and wind erosion characteristics of the prototype barrier. Studies on the biological component of the prototype barrier will include work on the initial revegetation of the surface, continued monitoring of the developing plant community, rooting depth and dispersion in the context of biointrusion potential, the role of plants in the hydrology of the surface and toe regions of the barrier, the role of plants in stabilizing the surface against water and wind erosion, and the role of burrowing animals in the hydrology and water and wind erosion of the barrier

Safety Performance Evaluations for the Vehicle Based Movable Barriers Using Full Scale Crash Tests

Directory of Open Access Journals (Sweden)

Jin Minsoo

2017-01-01

Full Text Available The present study aims to develop a prototype of large-size movable barriers to protect roadside workers from incoming vehicles to the road work area with the following functions: maximization of work space in the right and left directions, convenient mobility, and minimization of impact without modification of the inside of movable barriers into traffic lanes and perform safety performance assessment on passengers through full scale crash tests. The large movable barrier was divided into folder type and telescope type and the development stage was now at the prototype phase. A full scale crash test was conducted prior to certification test at a level of 90%. The full scale crash test result showed that both types of folder type movable barrier and telescope type movable barrier satisfied the standard of the passenger safety performance evaluation at a level of 90%.

Radon barrier: Method of testing airtightness

DEFF Research Database (Denmark)

Rasmussen, Torben Valdbjørn; Buch-Hansen, Thomas Cornelius

2017-01-01

The test method NBI 167/02 Radon membrane: Test of airtightness can be used for determining the airtightness of a radon barrier as a system solution. The test determines the air infiltration through the radon barrier for a number of levels of air pressure differences. The airflow through versus...... of the barrier with the low air pressure, through a well-defined opening, as a modification of the test method in general. Results, obtained using the improved test method, are shown for a number of radon barriers tested....

The outcomes of barrier protection in periwound skin and stoma care.

Science.gov (United States)

Stephen-Haynes, Jackie

This article considers the anatomy and physiology of the skin,wound healing, excoriation, maceration, peristomal skin and the importance of periwound protection. The results of a 54-patient study of the use of barrier film forming skin protection in periwound skin are presented and a 10-patient healthy volunteer experimental evaluation. The results confirm the effectiveness of barrier protection in healthy skin in an experimental evaluation and a 54-patient study requiring periwound protection.

Water erosion field tests for Hanford protective barriers: FY 1992 status report

International Nuclear Information System (INIS)

Gilmore, B.G.; Walters, W.H.

1993-11-01

Pacific Northwest Laboratory (PNL) conducted this study for the Office of Technology Development and the Office of Environmental Restoration of the US Department of Energy. The purpose of the study was to investigate the erosion potential of barrier soil covers from high-intensity rainfall events and to propose erosion mitigation criteria for the soil cover. Two sets of field plots were used in the testing program. Small plots (1 m 2 ) were used initially for scoping studies and larger plots (32.5 m 2 ) were used for a more comprehensive study of soil cover erosion. The study investigated the use of pea gravel admix and naturally established vegetation to reduce erosion of barrier soil covers

Distance and protective barrier effects on the composite resin degree of conversion

Science.gov (United States)

Coutinho, Margareth; Trevizam, Natália Carvalho; Takayassu, Renata Nakase; Leme, Ariene Arcas; Soares, Giulliana Panfiglio

2013-01-01

Context: The food wrap films are used to cover the tip of curing light units in order to avoid contamination and prevent damage to the light guide. However, their effects on resin polymerization are not fully known. Aims: We investigated the effects on restoration efficiency of a food wrap protective barrier used on the tip of curing light units. Materials and Methods: For each treatment, five replications were performed, a total of 60 bovine incisor. The degree of conversion (%DC) of restorations with the composite resin Opallis EA2 was evaluated using 3 curing light devices (Optilux 501, Optilight and Ultra LED) and 2 curing distances (0 and 5 mm). The composite resin was tested for restoration of cavities in bovine crowns. %DC values were measured by the Fourier transform infrared spectroscopy-attenuated total reflectance technique. Statistical Analysis Used: The data were analyzed using 3-way ANOVA and Tukey's test. Results: Use of the protective film lowered %DC (F = 4.13; P = 0.05), and the effects of curing distance were associated to the curing light device (F = 3.61; P = 0.03). Conclusions: The distance from the light curing tip and use of a translucent protective barrier on the light-cure device can both impair composite resin %DC. PMID:24015001

Influence of the geometry of protective barriers on the propagation of shock waves

Science.gov (United States)

Sochet, I.; Eveillard, S.; Vinçont, J. Y.; Piserchia, P. F.; Rocourt, X.

2017-03-01

The protection of industrial facilities, classified as hazardous, against accidental or intentional explosions represents a major challenge for the prevention of personal injury and property damage, which also involves social and economic issues. We consider here the use of physical barriers against the effects of these explosions, which include the pressure wave, the projection of fragments and the thermal flash. This approach can be recommended for the control of major industrial risks, but no specific instructions are available for its implementation. The influence of a protective barrier against a detonation-type explosion is studied in small-scale experiments. The effects of overpressure are examined over the entire path of the shock wave across the barrier and in the downstream zone to be protected. Two series of barrier structures are studied. The first series (A) of experiments investigates two types of barrier geometry with dimensions based on NATO recommendations. These recommendations stipulate that the barrier should be 2 m higher than the charge height, the thickness at the crest should be more than 0.5 m, while its length should be equal to twice the protected structure length and the bank slope should be equivalent to the angle of repose of the soil. The second series (B) of experiments investigates the influence of geometrical parameters of the barrier (thickness at the crest and inclination angles of the front and rear faces) on its protective effects. This project leads to an advance in our understanding of the physical phenomena involved in the propagation of blast waves resulting from an external explosion, in the area around a protective physical barrier. The study focuses on the dimensioning of protective barriers against overpressure effects arising from detonation and shows the advantage of using a barrier with a vertical front or rear face.

Scratch, wear and corrosion resistant organic inorganic hybrid materials for metals protection and barrier

International Nuclear Information System (INIS)

Barletta, M.; Gisario, A.; Puopolo, M.; Vesco, S.

2015-01-01

Highlights: • Polysiloxane coatings as protective barriers to delay erosion/corrosion of Fe 430 B metal substrates. • Methyl groups feature a very small steric hindrance and confer ductility to the Si–O–Si backbone. • Phenyl groups feature a larger steric hindrance, but they ensure stability and high chemical inertness. • Remarkable adhesion to the substrate, good scratch resistance and high wear endurance. • Innovative ways to design of long lasting protective barriers against corrosion and aggressive chemicals. - Abstract: Polysiloxanes are widely used as protective barriers to delay erosion/corrosion and increase chemical inertness of metal substrates. In the present work, a high molecular weight methyl phenyl polysiloxane resin was designed to manufacture a protective coating for Fe 430 B structural steel. Methyl groups feature very small steric hindrance and confer ductility to the Si–O–Si backbone of the organic inorganic hybrid resin, thus allowing the achievement of high thickness. Phenyl groups feature larger steric hindrance, but they ensure stability and high chemical inertness. Visual appearance and morphology of the coatings were studied by field emission scanning electron microscopy and contact gauge surface profilometry. Micro-mechanical response of the coatings was analyzed by instrumented progressive load scratch, while wear resistance by dry sliding linear reciprocating tribological tests. Lastly, chemical inertness and corrosion endurance of the coatings were evaluated by linear sweep voltammetry and chronoamperometry in aggressive acid environment. The resulting resins yielded protective materials, which feature remarkable adhesion to the substrate, good scratch resistance and high wear endurance, thus laying the foundations to manufacture long lasting protective barriers against corrosion and, more in general, against aggressive chemicals

Horizontal Acoustic Barriers for Protection from Seismic Waves

Directory of Open Access Journals (Sweden)

Sergey V. Kuznetsov

2011-01-01

Full Text Available The basic idea of a seismic barrier is to protect an area occupied by a building or a group of buildings from seismic waves. Depending on nature of seismic waves that are most probable in a specific region, different kinds of seismic barriers can be suggested. Herein, we consider a kind of a seismic barrier that represents a relatively thin surface layer that prevents surface seismic waves from propagating. The ideas for these barriers are based on one Chadwick's result concerning nonpropagation condition for Rayleigh waves in a clamped half-space, and Love's theorem that describes condition of nonexistence for Love waves. The numerical simulations reveal that to be effective the length of the horizontal barriers should be comparable to the typical wavelength.

Use of information barriers to protect classified information

International Nuclear Information System (INIS)

MacArthur, D.; Johnson, M.W.; Nicholas, N.J.; Whiteson, R.

1998-01-01

This paper discusses the detailed requirements for an information barrier (IB) for use with verification systems that employ intrusive measurement technologies. The IB would protect classified information in a bilateral or multilateral inspection of classified fissile material. Such a barrier must strike a balance between providing the inspecting party the confidence necessary to accept the measurement while protecting the inspected party's classified information. The authors discuss the structure required of an IB as well as the implications of the IB on detector system maintenance. A defense-in-depth approach is proposed which would provide assurance to the inspected party that all sensitive information is protected and to the inspecting party that the measurements are being performed as expected. The barrier could include elements of physical protection (such as locks, surveillance systems, and tamper indicators), hardening of key hardware components, assurance of capabilities and limitations of hardware and software systems, administrative controls, validation and verification of the systems, and error detection and resolution. Finally, an unclassified interface could be used to display and, possibly, record measurement results. The introduction of an IB into an analysis system may result in many otherwise innocuous components (detectors, analyzers, etc.) becoming classified and unavailable for routine maintenance by uncleared personnel. System maintenance and updating will be significantly simplified if the classification status of as many components as possible can be made reversible (i.e. the component can become unclassified following the removal of classified objects)

Evapotranspiration studies for protective barriers: Experimental plans

International Nuclear Information System (INIS)

Link, S.O.; Waugh, W.J.

1989-11-01

This document describes a general theory and experimental plans for predicting evapotranspiration in support of the Protective Barrier Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. 45 refs., 1 fig., 4 tabs

Merger of waste of lead in polyester resin for application of protection barriers

International Nuclear Information System (INIS)

Barros, Frieda Saicla; Paredes, Ramon Siguifredo Cortes

2010-01-01

This paper's main objective is the use of powdered lead waste obtained from the recycling of batteries embedded in polyester resin to be used as a protective barrier in environments subject to radiation. The aim is to enable a more economical procedure which is faster and more practical for use in walls where it is necessary to use protective barrier. This justification is reinforced having in sight the use of byproducts generated by industries, recycling them and using them as components in the development of barriers against ionizing radiation. In this study, we observed the morphological and physical-chemical properties of isolated and associated materials and performance analysis of the composite with respect to the attenuation properties for gamma rays, by means of experimental tests. For mixtures with 40% of waste lead, value referenced in mass, we obtained satisfactory results on the screen. Thus, we were able to combine the good performance of the composite with the reduction of environmental liabilities, in view of the recycling process of lead. (author)

Developing effective rockfall protection barriers for low energy impacts

Science.gov (United States)

Mentani, Alessio; Giacomini, Anna; Buzzi, Olivier; Govoni, Laura; Gottardi, Guido; Fityus, Stephen

2016-04-01

Recently, important progresses have been made towards the development of high capacity rockfall barriers (100 kJ - 8000 kJ). The interest of researchers and practitioners is now turning to the development of fences of minor capacity, whose use becomes essential in areas where rockfall events generally have low intensity and the use of high capacity barriers would be accompanied by excessive costs and high environmental impact. Low energy barriers can also provide a cost-effective solution even in areas where high energies events are expected. Results of full-scale tests are vital to any investigation on the behaviour of these structures. An experimental set-up has been developed at The University of Newcastle (AUS), to investigate the response of low energy rockfall barrier prototypes to low energy impacts. The Australian territory, and in particular New South Wales, is in fact characterised by rockfall events of low-to-medium intensity (50 kJ - 500 kJ) and the need of protection structures working within such energy range, is particularly felt [1]. The experiments involved the impact of a test block onto three spans, low energy barrier prototypes, made of steel structural posts, fully fixed at the base, side cables and a steel meshwork constituted by a double twist hexagonal wire net [2]. Test data enabled the development, calibration and assessment of FE models [3], on which non-linear and dynamic analyses have been performed addressing the effect of the block size. Results have shown that the response of the structure is strongly governed by the net. Data from tests conducted on the sole net and on the entire barrier showed in fact a similar trend, different to what typically observed for high capacity barriers, whose behaviour is also led by the presence of uphill cables and brakes. In particular, the numerical analyses have demonstrated a dependence of the net performance on the block size. In particular, a loss of capacity in the order of 50% occurred as the

Hanford Site Protective Barrier Development Program: Fiscal year 1990 highlights

International Nuclear Information System (INIS)

Cadwell, L.L.

1991-09-01

The Hanford Site Protective Barrier Development Program was jointly developed by Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company (WHC) to design and test an earthen cover system(s) that can be used to inhibit water infiltration; plant, animal, and human intrusion; and wind and water erosion. The joint PNL/WHC program was initiated in FY 1986. To date, research findings support the initial concepts of barrier designs for the Hanford Site. A fine-soil surface is planned to partition surface water into runoff and temporary storage. Transpiration by vegetation that grows in the fine-soil layer will return stored water to the atmosphere as will surface evaporation. A capillary break created by the interface of the fine-soil layer and coarser textured materials below will further limit the downward migration of surface water, making it available over a longer period of time for cycling to the atmosphere. Should water pass the interface, it will drain laterally through a coarse textured sand/gravel layer. Tested barrier designs appear to work adequately to prevent drainage under current and postulated wetter-climate (added precipitation) conditions. Wind and water erosion tasks are developing data to predict the extent of erosion on barrier surfaces. Data collected during the last year confirm the effectiveness of small burrowing animals in removing surface water. Water infiltrating through burrows of larger mammals was subsequently lost by natural processes. Natural analog and climate change studies are under way to provide credibility for modeling the performance of barrier designs over a long period of time and under shifts in climate. 10 refs., 30 figs

Hanford Site Protective Barrier Development Program: Fiscal year 1990 highlights

Energy Technology Data Exchange (ETDEWEB)

Cadwell, L.L. (ed.)

1991-09-01

The Hanford Site Protective Barrier Development Program was jointly developed by Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company (WHC) to design and test an earthen cover system(s) that can be used to inhibit water infiltration; plant, animal, and human intrusion; and wind and water erosion. The joint PNL/WHC program was initiated in FY 1986. To date, research findings support the initial concepts of barrier designs for the Hanford Site. A fine-soil surface is planned to partition surface water into runoff and temporary storage. Transpiration by vegetation that grows in the fine-soil layer will return stored water to the atmosphere as will surface evaporation. A capillary break created by the interface of the fine-soil layer and coarser textured materials below will further limit the downward migration of surface water, making it available over a longer period of time for cycling to the atmosphere. Should water pass the interface, it will drain laterally through a coarse textured sand/gravel layer. Tested barrier designs appear to work adequately to prevent drainage under current and postulated wetter-climate (added precipitation) conditions. Wind and water erosion tasks are developing data to predict the extent of erosion on barrier surfaces. Data collected during the last year confirm the effectiveness of small burrowing animals in removing surface water. Water infiltrating through burrows of larger mammals was subsequently lost by natural processes. Natural analog and climate change studies are under way to provide credibility for modeling the performance of barrier designs over a long period of time and under shifts in climate. 10 refs., 30 figs.

Physical protection system using activated barriers

International Nuclear Information System (INIS)

Timm, R.E.; Zinneman, T.E.; Haumann, J.R.; Flaugher, H.A.; Reigle, D.L.

1984-03-01

The Argonne National Laboratory has recently installed an activated barrier, the Access Denial System, to upgrade its security. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The Argonne National Laboratory is the first Department of Energy facility to use this device. Recent advancements in electronic components provide the total system support that makes the use of an activated barrier viable and desirable. The premise of an activated barrier is that it is deployed after a positive detection of an adversary is made and before the adversary can penetrate vital area. To accomplish this detection, sophisticated alarms, assessment, and communications must be integrated into a system that permits a security inspector to make a positive evaluation and to activate the barrier. The alarm sensor locations are selected to provide protection in depth. Closed circuit television is used with components that permit multiple video frames to be stored for automated, priority-based playback to the security inspector. Further, algorithms permit look-ahead surveillance of vital areas so that the security inspector can activate the access denial system in a timely manner and not be restricted to following the adversaries' penetration path(s)

Standards for the Protection of Skin Barrier Function.

Science.gov (United States)

Giménez-Arnau, Ana

2016-01-01

The skin is a vital organ, and through our skin we are in close contact with the entire environment. If we lose our skin we lose our life. The barrier function of the skin is mainly driven by the sophisticated epidermis in close relationship with the dermis. The epidermal epithelium is a mechanically, chemically, biologically and immunologically active barrier submitted to continuous turnover. The barrier function of the skin needs to be protected and restored. Its own physiology allows its recovery, but many times this is not sufficient. This chapter is focused on the standards to restore, treat and prevent barrier function disruption. These standards were developed from a scientific, academic and clinical point of view. There is a lack of standardized administrative recommendations. Still, there is a walk to do that will help to reduce the social and economic burden of diseases characterized by an abnormal skin barrier function. © 2016 S. Karger AG, Basel.

Information barriers for the protection of sensitive information

International Nuclear Information System (INIS)

Dougan, A.D.; Dunn, J.; Seager, K.; Smith, M.; Beach, D.; Clinton, J.; Vanier, P.

2013-01-01

An Information Barrier is a combination of technology and procedures that prevent the release of a host country's sensitive information to a monitoring party during an inspection of a sensitive item, while enabling assurance of an accurate assessment of host country declarations regarding the item. Information barriers, as a concept, arose from the need to balance two competing requirements - specifically, certification of information protection by a host country and authentication of measurement and information accuracy by a monitoring party. The U.S. Department of Energy's National Nuclear Security Administration, in conjunction with several U.S. National Laboratories, has explored information barrier development in detail, and has continued the evolution of essential work done by the U.S. Information Barrier Working Group beginning in the late 1990's, and other international efforts, including the U.S.-Russia-IAEA Trilateral Initiative. This paper explains the rationale for information barriers, and explores the development and application of information barrier concepts for potential future arms control initiatives, including recent work and advances in capabilities. It also considers applications of information barrier concepts applied in other fields.The paper is followed by the slides of the presentation. (authors)

Natural analog study of engineered protective barriers at the Hanford Site

International Nuclear Information System (INIS)

Bjornstad, B.N.; Teel, S.S.

1993-09-01

The purpose of this study is to evaluate surficial sedimentary deposits formed in the Pasco Basin over the geologic past as analogs for engineered protective barriers. Evidence for likely changes to be expected in an engineered barrier are preserved in geologically recent deposits. Although the design life of the engineered bonier is only 1,000 years, soils and sediments of this age are uncommon in the Pasco Basin. The evidence of and probability for the following natural processes that could adversely affect the long-term stability of an engineered protective barrier reviewed in this report are deflation by wind, soil compaction, soil eluviation/illuviation, bioturbation, and cryoturbation

Numerical simulations of capillary barrier field tests

International Nuclear Information System (INIS)

Morris, C.E.; Stormont, J.C.

1997-01-01

Numerical simulations of two capillary barrier systems tested in the field were conducted to determine if an unsaturated flow model could accurately represent the observed results. The field data was collected from two 7-m long, 1.2-m thick capillary barriers built on a 10% grade that were being tested to investigate their ability to laterally divert water downslope. One system had a homogeneous fine layer, while the fine soil of the second barrier was layered to increase its ability to laterally divert infiltrating moisture. The barriers were subjected first to constant infiltration while minimizing evaporative losses and then were exposed to ambient conditions. The continuous infiltration period of the field tests for the two barrier systems was modelled to determine the ability of an existing code to accurately represent capillary barrier behavior embodied in these two designs. Differences between the field test and the model data were found, but in general the simulations appeared to adequately reproduce the response of the test systems. Accounting for moisture retention hysteresis in the layered system will potentially lead to more accurate modelling results and is likely to be important when developing reasonable predictions of capillary barrier behavior

Autophagy inhibitor 3-methyladenine protects against endothelial cell barrier dysfunction in acute lung injury.

Science.gov (United States)

Slavin, Spencer A; Leonard, Antony; Grose, Valerie; Fazal, Fabeha; Rahman, Arshad

2018-03-01

Autophagy is an evolutionarily conserved cellular process that facilitates the continuous recycling of intracellular components (organelles and proteins) and provides an alternative source of energy when nutrients are scarce. Recent studies have implicated autophagy in many disorders, including pulmonary diseases. However, the role of autophagy in endothelial cell (EC) barrier dysfunction and its relevance in the context of acute lung injury (ALI) remain uncertain. Here, we provide evidence that autophagy is a critical component of EC barrier disruption in ALI. Using an aerosolized bacterial lipopolysaccharide (LPS) inhalation mouse model of ALI, we found that administration of the autophagy inhibitor 3-methyladenine (3-MA), either prophylactically or therapeutically, markedly reduced lung vascular leakage and tissue edema. 3-MA was also effective in reducing the levels of proinflammatory mediators and lung neutrophil sequestration induced by LPS. To test the possibility that autophagy in EC could contribute to lung vascular injury, we addressed its role in the mechanism of EC barrier disruption. Knockdown of ATG5, an essential regulator of autophagy, attenuated thrombin-induced EC barrier disruption, confirming the involvement of autophagy in the response. Similarly, exposure of cells to 3-MA, either before or after thrombin, protected against EC barrier dysfunction by inhibiting the cleavage and loss of vascular endothelial cadherin at adherens junctions, as well as formation of actin stress fibers. 3-MA also reversed LPS-induced EC barrier disruption. Together, these data imply a role of autophagy in lung vascular injury and reveal the protective and therapeutic utility of 3-MA against ALI.

Engineered Barrier Testing at the INEEL Engineered Barriers Test Facility: FY-1997 and FY-1998

International Nuclear Information System (INIS)

Keck, K. N.; Porro, I.

1998-01-01

Engineered barriers of two designs are being tested at the Engineered Barriers Test Facility (EBTF) at the Idaho National Engineering and Environmental Laboratory. This report describes the test facility, barrier designs, and instruments used to monitor the test plots. Wetting tests conducted on the test plots in FY-97 are described and data collected from monitoring the test plots before, during and after the wetting tests are used to evaluate the performance of the covers during FY-97 and FY-98. Replicates of two engineered barrier designs were constructed in the EBTF cells. The first design comprises a thick, vegetated soil cover. The second design incorporates a capillary/biobarrier within the vegtated soil cover. The capillary barrier uses the textural break between an upper, fine textured soil and a lower, coarser-textured gravel layer to inhibit drainage under unsaturated conditions while increasing soil moisture storage in the root zone. Evaporation and transpiration by plants (although the test plots have not yet been vegetated) are used to recycle water stored in the soil back to the atmosphere. A geotextile fabric is used to maintain separation of the soil and gravel layers. A thick layer of cobbles beneath the gravel layer serves as a biobarrier to prevent intrusion of plant roots and burrowing animals into underlying waste (there is no waste in the test plots). Each test plot was instrumented with time domain reflectometry probes and neutron probe access tubes to measure moisture contents, tensiometers, heat dissipation sensors, and thermocouple psychrometers to measure matric potentials, thermocouples to measure soil temperature, and ion-exchange resin beads to monitor tracer movement. Each drainage sump is equipped with a tipping bucket instrument and pressure transducer to measure drainage. Precipitation is measured using a heated rain gauge located at the EBTF. Instrument calibration equation coefficients are presented, and data reduction

Radon barrier field-test monitoring at Grand Junction tailings pile

International Nuclear Information System (INIS)

Freeman, H.D.; Hartley, J.N.; Gee, G.W.

1983-11-01

Pacific Northwest Laboratory (PNL), as part of the Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) technology development program, has conducted three large-scale field tests of radon covers at the uranium mill tailings pile in Grand Junction, Colorado. The barrier systems, monitored for radon flux for over two years, include earthen, multilayer, and asphalt emulsion covers. Results of the monitoring have shown that a variety of cover systems can meet the Environmental Protection Agency (EPA) standard. The most effective covers tested were asphalt emulsion and earthen (mancos shale). 10 references, 7 figures, 1 table

New solution for transport and industrial noise protection through reflective noise barriers

Directory of Open Access Journals (Sweden)

Kralov Ivan

2017-01-01

Full Text Available A new solution for protection of transportation and industrial noise through reflective noise barriers is proposed and investigated in this study. The new solution combines the advantages of the known barriers and has its own advantages in addition. The preliminary results show a very good level of noise reduction for this type of barriers.

Deployment Efficiency and Barrier Effectiveness Testing of a Temporary Anti-Personnel (TAP) Barrier System.

Energy Technology Data Exchange (ETDEWEB)

Allen, David James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hedrick, Charles D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Martinez, Ruben [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-02-01

This report documents tests conducted by Sandia National Laboratories (SNL) on behalf of the U.S. Department of State to evaluate a temporary anti-personnel (TAP) barrier system developed by Mitigation Technologies. For this, the SNL Denial and Structural Assessment department developed a test protocol for the evaluation of the TAP barrier system on the basis of deployment efficiency and barrier effectiveness against a riotous/mob attack threat. The test protocol was then executed by SNL personnel and the results of the testing are documented.

K West basin isolation barrier leak rate test

International Nuclear Information System (INIS)

Whitehurst, R.; McCracken, K.; Papenfuss, J.N.

1994-01-01

This document establishes the procedure for performing the acceptance test on the two isolation barriers being installed in K West basin. This acceptance test procedure shall be used to: First establish a basin water loss rate prior to installation of the two isolation barriers between the main basin and the discharge chute in K-Basin West. Second, perform an acceptance test to verify an acceptable leakage rate through the barrier seals

ANALYSIS OF FLEXIBLE BARRIERS USED AS SAFETY PROTECTION IN WOODWORKING

Directory of Open Access Journals (Sweden)

Ana Pavlovic

2016-03-01

Full Text Available Machine tools use physical barriers, made by flexible thermoplastic materials, to protect the environment and the operators against the projections of wood chips and parts of cutting tools. These barriers constitute a partial closure and allow the passage of the workpiece, being simultaneously able to contain sharp fragments projected at high speed. The present research was conducted with the aim to evaluate the real effectiveness of these barriers, to investigate their dynamic behaviour by numerical simulations. Results showed that these barriers, if properly considered, could retain heavier masses and higher speeds. The research also allowed, in fact, to investigate the influence of several factors in design, selection and use, as material, shape, position, assemblages and many others, highlighting weaknesses and identifying possible measures to increase its effectiveness.

105K West Isolation Barrier Acceptance Test results

International Nuclear Information System (INIS)

McCracken, K.J.; Irwin, J.J.

1995-01-01

The objective of this document is to report and interpret the findings of the isolation barrier acceptance tests performed in 105KW/100K. The tests were performed in accordance with the test plan and acceptance test procedure. The test report contains the test data. This document compares the test data against the criteria. A discussion of the leak rate analytical characterization describes how the flow characteristics flow rate will be determined using the test data from the test report. Two modes of water loss were considered; basin and/or discharge chute leakage, and evaporation. An initial test established baseline leakage data and instrumentation performance. Test 2 evaluated the sealing performance of the isolation barrier by inducing an 11 in. (27.9 cm) level differential across the barrier. The leak rate at this 11 in. (27.9 cm) level is extrapolated to the 16 ft. (4.9 m) level differential postulated in the DBE post seismic event. If the leak rate, adjusted for evaporation and basin leakage (determined from Test 1), is less than the SAR limit of 1,500 gph (5,680 lph) at a 16 ft (4.9 m) level differential, the barriers pass the acceptance test

Test device for measuring permeability of a barrier material

Science.gov (United States)

Reese, Matthew; Dameron, Arrelaine; Kempe, Michael

2014-03-04

A test device for measuring permeability of a barrier material. An exemplary device comprises a test card having a thin-film conductor-pattern formed thereon and an edge seal which seals the test card to the barrier material. Another exemplary embodiment is an electrical calcium test device comprising: a test card an impermeable spacer, an edge seal which seals the test card to the spacer and an edge seal which seals the spacer to the barrier material.

Using virtual reality in the training of security staff and evaluation of physical protection barriers in nuclear facilities

Energy Technology Data Exchange (ETDEWEB)

Augusto, Silas C.; Mol, Antonio C.A.; Mol, Pedro C.; Sales, Douglas S. [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil)], e-mail: silas@ien.gov.br, e-mail: mol@ien.gov.br, e-mail: pedro98@gmail.com, e-mail: dsales@ien.gov.br

2009-07-01

The physical security of facilities containing radioactive objects, an already important matter, now has a new aggravating factor: the existence of groups intending to obtain radioactive materials for the purpose of intentionally induce radioactive contamination incidents, as for example the explosion of dirty bombs in populated regions, damaging both people and environment. In this context, the physical security of such facilities must be reinforced so to reduce the possibilities of such incidents. This paper presents a adapted game engine used as a virtual reality system, enabling the modeling and simulation of scenarios of nuclear facilities containing radioactive objects. In these scenarios, the physical protection barriers, as fences and walls, are simulated along with vigilance screens. Using a computer network, several users can participate simultaneously in the simulation, being represented by avatars. Users can play the roles of both invaders and security staff. The invaders have as objective to surpass the facility's physical protection barriers to steal radioactive objects and flee. The security staff have as objective to prevent and stop the theft of radioactive objects from the facility. The system can be used to analysis simulated scenarios and train vigilance/security staff. A test scenario was already developed and used, and the preliminary tests had satisfactory results, as they enabled the evaluation of the physical protection barriers of the virtual facility, and the training of those who participated in the simulations in the functions of a security staff. (author)

Using virtual reality in the training of security staff and evaluation of physical protection barriers in nuclear facilities

International Nuclear Information System (INIS)

Augusto, Silas C.; Mol, Antonio C.A.; Mol, Pedro C.; Sales, Douglas S.

2009-01-01

The physical security of facilities containing radioactive objects, an already important matter, now has a new aggravating factor: the existence of groups intending to obtain radioactive materials for the purpose of intentionally induce radioactive contamination incidents, as for example the explosion of dirty bombs in populated regions, damaging both people and environment. In this context, the physical security of such facilities must be reinforced so to reduce the possibilities of such incidents. This paper presents a adapted game engine used as a virtual reality system, enabling the modeling and simulation of scenarios of nuclear facilities containing radioactive objects. In these scenarios, the physical protection barriers, as fences and walls, are simulated along with vigilance screens. Using a computer network, several users can participate simultaneously in the simulation, being represented by avatars. Users can play the roles of both invaders and security staff. The invaders have as objective to surpass the facility's physical protection barriers to steal radioactive objects and flee. The security staff have as objective to prevent and stop the theft of radioactive objects from the facility. The system can be used to analysis simulated scenarios and train vigilance/security staff. A test scenario was already developed and used, and the preliminary tests had satisfactory results, as they enabled the evaluation of the physical protection barriers of the virtual facility, and the training of those who participated in the simulations in the functions of a security staff. (author)

Engineered Barrier Test Facility status report, 1984

International Nuclear Information System (INIS)

Phillips, S.J.; Adams, M.R.; Gilbert, T.W.; Meinhardt, C.C.; Mitchell, R.M.; Waugh, W.J.

1985-02-01

This report provides a general summary of activities completed to date at the Hanford Engineered Barrier Test Facility. This facility is used to test and compare construction practices and performance of alternative designs of engineered barrier cover systems. These cover systems are being evaluated for potential use for isolation and confinement of buried waste disposal structures

The development and validation of a mathematical model for the design of protection barriers for nuclear powered ships. Report for 10 June 1976--31 March 1978

International Nuclear Information System (INIS)

Chang, P.Y.

1978-03-01

A mathematical model for the analysis and design of protection barrier structures is developed. The analysis procedure is based on the collapse theorems, i.e., the Upper Bound Theorem and the Lower Bound Theorem. The collision protection barrier is analyzed by a finite element program with capabilities of nonlinear and elastoplastic analysis. The results obtained from the mathematical model are compared with those obtained from the collision model tests

Field Lysimeter Test Facility: Second year (FY 1989) test results

International Nuclear Information System (INIS)

Campbell, M.D.; Gee, G.W.; Kanyid, M.J.; Rockhold, M.L.

1990-04-01

The Record of Decision associated with the Hanford Defense Waste Environmental Impact Statement (53 FR 12449-53) commits to an evaluation of the use of protective barriers placed over near-surface wastes. The barrier must protect against wind and water erosion and limit plant and animal intrusion and infiltration of water. Successful conclusion of this program will yield the necessary protective barrier design for near-surface waste isolation. This report presents results from the second year of tests at the FLTF. The primary objective of testing protective barriers at the FLTF was to measure the water budgets within the various barriers and assess the effectiveness of their designs in limiting water intrusion into the zone beneath each barrier. Information obtained from these measurements is intended for use in refining barrier designs. Four elements of water budget were measured during the year: precipitation, evaporation, storage, and drainage. Run-off, which is a fifth element of a complete water budget, was made negligible by a lip on the lysimeters that protrudes 5 cm above the soil surface to prevent run-off. A secondary objective of testing protective barriers at the FLTF was to refine procedures and equipment to support data collection for verification of the computer model needed for long-term projections of barrier performance. 6 refs

Protective Effects of Bifidobacterium on Intestinal Barrier Function in LPS-Induced Enterocyte Barrier Injury of Caco-2 Monolayers and in a Rat NEC Model.

Science.gov (United States)

Ling, Xiang; Linglong, Peng; Weixia, Du; Hong, Wei

2016-01-01

Zonulin protein is a newly discovered modulator which modulates the permeability of the intestinal epithelial barrier by disassembling intercellular tight junctions (TJ). Disruption of TJ is associated with neonatal necrotizing enterocolitis (NEC). It has been shown bifidobacterium could protect the intestinal barrier function and prophylactical administration of bifidobacterium has beneficial effects in NEC patients and animals. However, it is still unknown whether the zonulin is involved in the gut barrier dysfunction of NEC, and the protective mechanisms of bifidobacterium on intestinal barrier function are also not well understood. The present study aims to investigate the effects of bifidobacterium on intestinal barrier function, zonulin regulation, and TJ integrity both in LPS-induced enterocyte barrier injury of Caco-2 monolayers and in a rat NEC model. Our results showed bifidobacterium markedly attenuated the decrease in transepithelial electrical resistance and the increase in paracellular permeability in the Caco-2 monolayers treated with LPS (P zonulin release (P zonulin (P zonulin protein release and improvement of intestinal TJ integrity.

Animal intrusion studies for protective barriers: Status report for FY 1988

Energy Technology Data Exchange (ETDEWEB)

Cadwell, L.L.; Eberhardt, L.E.; Simmons, M.A.

1989-05-01

The objective of the Biointrusion Control Task is to provide technical support to Westinghouse Hanford Company's Protective Barrier Development Program for evaluating and predicting potential impacts of animal burrowing on long-term barrier performance. This document reviews the major accomplishments for FY 1988, which is the initial year of the work. The scope of work includes a literature review, field studies, and modeling to assess burrowing impacts as they may contribute to increased infiltration of surface water through barriers, increased quantities of soil available for erosion because of surface soil disturbance, and direct physical transport of contaminants to the surface. 68 refs., 8 figs., 5 tabs.

The implications of trade policy and 'natural' barriers induced protection for aggregate demand for imports: Evidence for Malawi

OpenAIRE

Zgovu, Evious K.

2003-01-01

This paper analyses the relative importance of trade policy and ‘natural’ trade barriers in the demand for imports for Malawi, a geographically landlocked sub-Saharan African economy, using an augmented dynamic import demand model. Incidence analysis of protection shows that pre-liberalisation trade policy barriers were greater than ‘natural’ barriers but in post-liberalisation ‘natural’ barriers were greater. Econometric analysis of the import demand model shows that ‘true’ protection of imp...

Lactobacillus protects the integrity of intestinal epithelial barrier damaged by pathogenic bacteria

Directory of Open Access Journals (Sweden)

Qinghua eYu

2015-03-01

Full Text Available Pathogens invade intestinal mucosal barrier through phagocytosis of antigen presenting cells (dendritic cell, microfold cells, or through the invasion into the intestinal epithelial directly. Some pathogens could damage the cell junction between epithelial cells and use the paracellular pathway as an entrance to invade. Moreover, some Lactobacillus could inhibit the adhesion of the pathogens and protect the integrity of the cell junction and mucosal barrier. This research focused on the potential therapeutic effect of Lactobacillus fructosus (L. fructosus C2 to attenuate ETEC K88 or S. typhimurium SL1344 induced changes to mucosal barrier. The results demonstrated that treatment of polarized Caco-2 cells with L. fructosus C2 reduced the permeation of dextran, and expression of IL-8, p-ERK and p-JNK when cells were infected with pathogenic bacteria. The findings indicated that L. fructosus C2 exerted a protective effect against the damage to the integrity of Caco-2 cells by ETEC or S. typhimurium infection.

Measurement of leakage and design for the protective barrier of the high energy radiation therapy room

International Nuclear Information System (INIS)

Chu, S.S.; Park, C.Y.

1981-01-01

The logical development of an optimum structural shielding design and the computation of protective barriers for high energy radiation therapy room, Toshiba 13 MeV are presented. We obtained following results by comparison in between the precalculating values and actual survey after complete installation of radiogenerating units. 1) The calculating formula for the protective barrier written in NCRP report no. 34(1970) was the most ideal and economic calculating methods for the construction of barrier and to determine thickness for the meeting requirements of the number of patients of 80-100 in daily treatment. 2) The precalculating values of protective barrier are 5 times more protective than that of actual measurement. It is depending on radiation workload and utilization the data most securely. 3) The dose rate during exposure are 2-10 mR/hr at out of the door and the control room. 4) The foul smelling and ozone gas production from long exposure of cancer patients cannot be estimated when the room is ill ventilated. (author)

Prototype Engineered Barrier System Field Tests

International Nuclear Information System (INIS)

Ramirez, A.L.; Beatty, J.; Buscheck, T.A.

1989-01-01

This paper presents selected preliminary results obtained during the first 54 days of the Prototype Engineered Barrier System Field Tests (PEBSFT) that are being performed in G-Tunnel within the Nevada Test Site. The test described is a precursor to the Engineered Barrier Systems Field Tests (EBSFT). The EBSFT will consist of in situ tests of the geohydrologic and geochemical environment in the near field (within a few meters) of heaters emplaced in welded tuff to simulate the thermal effects of waste packages. The PEBSFTs are being conducted to evaluate the applicability of measurement techniques, numerical models, and procedures for future investigations that will be conducted in the Exploratory Shaft Facilities of the Yucca Mountain Project (YMP). The paper discusses the evolution of hydrothermal behavior during the prototype test, including rock temperatures, changes in rock moisture content, air permeability of fractures, gas pressures, and rock mass gas-phase humidity. 10 refs., 12 figs

Characterization for capillary barriers effects in a sand box test using time-lapsed GPR measurements

Science.gov (United States)

Kuroda, S.; Ishii, N.; Morii, T.

2017-12-01

Capillary barriers have been known as the method to protect subsurface regions against infiltration from soil surface. It is caused by essentially heterogeneous structure in permeability or soil physical property and produce non-uniform infiltration process then, in order to estimate the actual situation of the capillary barrier effect, the site-characterization with imaging technique like geophysical prospecting is effective. In this study, we examine the applicability of GPR to characterization for capillary barriers. We built a sand box with 90x340x90cm in which a thin high-permeable gravel layer was embedded as a capillary barrier. We conducted an infiltration test in the sand box using porous tube array for irrigation. It is expected to lead to non-uniform flow of soil water induced by capillary barrier effects. We monitored this process by various types of GPR measurements, including time-lapsed common offset profiling (COP) with multi- frequency antenna and transmission measurements like cross-borehole radar. At first, we conducted GPR common-offset survey. It could show the depth of capillary barrier in sand box. After that we conducted the infiltration test and GPR monitoring for infiltration process. GPR profiles can detect the wetting front and estimate water content change in the soil layer above the capillary barrier. From spatial change in these results we can estimate the effect of capillary barrier and the zone where the break through occur or not. Based on these results, we will discuss the applicability of GPR for monitoring the phenomena around the capillary barrier of soil. At first, we conducted GPR common-offset survey. It could show the depth of capillary barrier in sand box. After that we conducted the infiltration test and GPR monitoring for infiltration process. GPR profiles can detect the wetting front and estimate water content change in the soil layer above the capillary barrier. From spatial change in these results we can estimate the

Benefits, Facilitators, Barriers, and Strategies to Improve Pesticide Protective Behaviors: Insights from Farmworkers in North Carolina Tobacco Fields.

Science.gov (United States)

Walton, AnnMarie Lee; LePrevost, Catherine E; Linnan, Laura; Sanchez-Birkhead, Ana; Mooney, Kathi

2017-06-23

Pesticide exposure is associated with deleterious health effects. Prior studies suggest Latino farmworkers perceive little control over their occupational health. Using the Health Belief Model as a theoretical guide, we explored the perceptions of Latino farmworkers working in tobacco in North Carolina ( n = 72) about benefits and facilitators of pesticide protective behaviors as well as barriers, and strategies to overcome barriers to their use. Interviews were conducted with participants at farmworker housing during non-work time. Qualitative data were analyzed using ATLAS.ti. Farmworkers recognized pesticide protective behaviors as helping them to not get sick and stay healthy. Farmworkers perceived work experience as facilitating protective behaviors. Wetness in the field was the most commonly cited barrier to protective behavior use. To overcome this barrier, farmworkers suggested use of water-resistant outerwear, as well as packing a change of clothes for mid-day, with space and time to change provided by employers. Examination of the efficacy and feasibility of farmworkers' suggestions for addressing barriers is warranted. Training and behavior modeling by experienced peers may improve behavior adoption and perceived control.

Field testing of asphalt-emulsion radon-barrier system

International Nuclear Information System (INIS)

Hartley, J.N.; Freeman, H.D.; Baker, E.G.; Elmore, M.R.; Nelson, D.A.; Voss, C.F.; Koehmstedt, P.L.

1981-09-01

Three years of laboratory and field testing have demonstrated that asphalt emulsion seals are effective radon diffusion barriers. Both laboratory and field tests in 1979, 1980 and 1981 have shown that an asphalt emulsion seal can reduce radon fluxes by greater than 99.9%. The effective diffusion coefficient for the various asphalt emulsion admix seals averages about 10 -6 cm 2 /s. The 1981 joint field test is a culmination of all the technology developed to date for asphalt emulsion radon barrier systems. Preliminary results of this field test and the results of the 1980 field test are presented. 18 figures, 6 tables

Testing the psychological barrier in borsa Istanbul

OpenAIRE

Çinko, Murat

2014-01-01

The aim of the study is to find out the existence of “psychological barriers” in Borsa Istanbul. The importance of this study is that Psychological Barrier has never been tested in Borsa Istanbul. The data set consists of 2523 daily closing index values between 03 April 2003 to 12 April 2013. The reason of choosing these dates is that all index values have five digits. Chi - Square goodness of fit test and regression analysis indicate that there exists a psychological barrier at thousands lev...

Protective Effects of Bifidobacterium on Intestinal Barrier Function in LPS-Induced Enterocyte Barrier Injury of Caco-2 Monolayers and in a Rat NEC Model.

Directory of Open Access Journals (Sweden)

Xiang Ling

Full Text Available Zonulin protein is a newly discovered modulator which modulates the permeability of the intestinal epithelial barrier by disassembling intercellular tight junctions (TJ. Disruption of TJ is associated with neonatal necrotizing enterocolitis (NEC. It has been shown bifidobacterium could protect the intestinal barrier function and prophylactical administration of bifidobacterium has beneficial effects in NEC patients and animals. However, it is still unknown whether the zonulin is involved in the gut barrier dysfunction of NEC, and the protective mechanisms of bifidobacterium on intestinal barrier function are also not well understood. The present study aims to investigate the effects of bifidobacterium on intestinal barrier function, zonulin regulation, and TJ integrity both in LPS-induced enterocyte barrier injury of Caco-2 monolayers and in a rat NEC model. Our results showed bifidobacterium markedly attenuated the decrease in transepithelial electrical resistance and the increase in paracellular permeability in the Caco-2 monolayers treated with LPS (P < 0.01. Compared with the LPS group, bifidobacterium significantly decreased the production of IL-6 and TNF-α (P < 0.01 and suppressed zonulin release (P < 0.05. In addition, bifidobacterium pretreatment up-regulated occludin, claudin-3 and ZO-1 expression (P < 0.01 and also preserved these proteins localization at TJ compared with the LPS group. In the in vivo study, bifidobacterium decreased the incidence of NEC from 88 to 47% (P < 0.05 and reduced the severity in the NEC model. Increased levels of IL-6 and TNF-α in the ileum of NEC rats were normalized in bifidobacterium treated rats (P < 0.05. Moreover, administration of bifidobacterium attenuated the increase in intestinal permeability (P < 0.01, decreased the levels of serum zonulin (P < 0.05, normalized the expression and localization of TJ proteins in the ileum compared with animals with NEC. We concluded that bifidobacterium may

Few-layer MoS2 as nitrogen protective barrier

Science.gov (United States)

Akbali, B.; Yanilmaz, A.; Tomak, A.; Tongay, S.; Çelebi, C.; Sahin, H.

2017-10-01

We report experimental and theoretical investigations of the observed barrier behavior of few-layer MoS2 against nitrogenation. Owing to its low-strength shearing, low friction coefficient, and high lubricity, MoS2 exhibits the demeanor of a natural N-resistant coating material. Raman spectroscopy is done to determine the coating capability of MoS2 on graphene. Surface morphology of our MoS2/graphene heterostructure is characterized by using optical microscopy, scanning electron microscopy, and atomic force microscopy. In addition, density functional theory-based calculations are performed to understand the energy barrier performance of MoS2 against nitrogenation. The penetration of nitrogen atoms through a defect-free MoS2 layer is prevented by a very high vertical diffusion barrier, indicating that MoS2 can serve as a protective layer for the nitrogenation of graphene. Our experimental and theoretical results show that MoS2 material can be used both as an efficient nanocoating material and as a nanoscale mask for selective nitrogenation of graphene layer.

Subsurface barrier demonstration test strategy and performance specification

International Nuclear Information System (INIS)

Treat, R.L.; Cruse, J.M.

1994-05-01

This document was developed to help specify a major demonstration test project of subsurface barrier systems supporting the Tank Waste Remediation System (TWRS) Program. The document focuses discussion on requirements applicable to demonstration of three subsurface barrier concepts: (1) Injected Material, (2) Cryogenic, and (3) Desiccant. Detailed requirements are provided for initial qualification of a technology proposal followed by the pre-demonstration and demonstration test requirements and specifications. Each requirement and specification is accompanied by a discussion of the rationale for it. The document also includes information on the Hanford Site tank farms and related data; the related and currently active technology development projects within the DOE's EM-50 Program; and the overall demonstration test strategy. Procurement activities and other preparations for actual demonstration testing are on hold until a decision is made regarding further development of subsurface barriers. Accordingly, this document is being issued for information only

Endothelium-Derived 5-Methoxytryptophan Protects Endothelial Barrier Function by Blocking p38 MAPK Activation.

Directory of Open Access Journals (Sweden)

Ling-Yun Chu

Full Text Available The endothelial junction is tightly controlled to restrict the passage of blood cells and solutes. Disruption of endothelial barrier function by bacterial endotoxins, cytokines or growth factors results in inflammation and vascular damage leading to vascular diseases. We have identified 5-methoxytryptophan (5-MTP as an anti-inflammatory factor by metabolomic analysis of conditioned medium of human fibroblasts. Here we postulated that endothelial cells release 5-MTP to protect the barrier function. Conditioned medium of human umbilical vein endothelial cells (HUVECs prevented endothelial hyperpermeability and VE-cadherin downregulation induced by VEGF, LPS and cytokines. We analyzed the metabolomic profile of HUVEC conditioned medium and detected 5-MTP but not melatonin, serotonin or their catabolites, which was confirmed by enzyme-linked immunosorbent assay. Addition of synthetic pure 5-MTP preserved VE-cadherin and maintained barrier function despite challenge with pro-inflammatory mediators. Tryptophan hydroxylase-1, an enzyme required for 5-MTP biosynthesis, was downregulated in HUVECs by pro-inflammatory mediators and it was accompanied by reduction of 5-MTP. 5-MTP protected VE-cadherin and prevented endothelial hyperpermeability by blocking p38 MAPK activation. A chemical inhibitor of p38 MAPK, SB202190, exhibited a similar protective effect as 5-MTP. To determine whether 5-MTP prevents vascular hyperpermeability in vivo, we evaluated the effect of 5-MTP administration on LPS-induced murine microvascular permeability with Evans blue. 5-MTP significantly prevented Evans blue dye leakage. Our findings indicate that 5-MTP is a new class of endothelium-derived molecules which protects endothelial barrier function by blocking p38 MAPK.

Development and psychometric testing of a barriers to HIV testing scale among individuals with HIV infection in Sweden; The Barriers to HIV testing scale-Karolinska version.

Science.gov (United States)

Wiklander, Maria; Brännström, Johanna; Svedhem, Veronica; Eriksson, Lars E

2015-11-19

Barriers to HIV testing experienced by individuals at risk for HIV can result in treatment delay and further transmission of the disease. Instruments to systematically measure barriers are scarce, but could contribute to improved strategies for HIV testing. Aims of this study were to develop and test a barriers to HIV testing scale in a Swedish context. An 18-item scale was developed, based on an existing scale with addition of six new items related to fear of the disease or negative consequences of being diagnosed as HIV-infected. Items were phrased as statements about potential barriers with a three-point response format representing not important, somewhat important, and very important. The scale was evaluated regarding missing values, floor and ceiling effects, exploratory factor analysis, and internal consistencies. The questionnaire was completed by 292 adults recently diagnosed with HIV infection, of whom 7 were excluded (≥9 items missing) and 285 were included (≥12 items completed) in the analyses. The participants were 18-70 years old (mean 40.5, SD 11.5), 39 % were females and 77 % born outside Sweden. Routes of transmission were heterosexual transmission 63 %, male to male sex 20 %, intravenous drug use 5 %, blood product/transfusion 2 %, and unknown 9 %. All scale items had <3 % missing values. The data was feasible for factor analysis (KMO = 0.92) and a four-factor solution was chosen, based on level of explained common variance (58.64 %) and interpretability of factor structure. The factors were interpreted as; personal consequences, structural barriers, social and economic security, and confidentiality. Ratings on the minimum level (suggested barrier not important) were common, resulting in substantial floor effects on the scales. The scales were internally consistent (Cronbach's α 0.78-0.91). This study gives preliminary evidence of the scale being feasible, reliable and valid to identify different types of barriers to HIV testing.

Barriers to HIV testing in Cote d'Ivoire: the role of individual characteristics and testing modalities.

Directory of Open Access Journals (Sweden)

Kévin Jean

Full Text Available BACKGROUND: Expanding HIV testing requires a better understanding of barriers to its uptake. We investigated barriers to HIV testing in Côte d'Ivoire, taking into account test circumstances (client vs. provider-initiated. METHODS: We used data from the 2005 nationally representative Demographic and Health Survey conducted in Côte d'Ivoire. Socio-demographic characteristics, sexual behaviour and knowledge and attitudes toward HIV/AIDS associated with recent (<2 years HIV testing were identified using gender-specific univariate and multivariate logistic regressions. Among women, differential effects of barriers to testing according to test circumstance (whether they have been offered for a prenatal test or not were assessed through interaction tests. RESULTS: Recent HIV testing was reported by 6.1% of men and 9.5% of women (including 4.6% as part of antenatal care. Among men, having a low socioeconomic status, having a low HIV-related knowledge level and being employed [compared to those inactive: adjusted Odds Ratio (aOR 0.46; 95% confidence interval (CI 0.25-0.87] were associated with lower proportions of recent HIV testing. Among women without a prenatal HIV testing offer, living outside the capital (aOR 0.38; CI 0.19-0.77 and reporting a unique lifetime sexual partner constituted additional barriers to HIV testing. By contrast, among women recently offered to be tested in prenatal care, none of these variables was found to be associated with recent HIV testing. CONCLUSIONS: Various dimensions of individuals' characteristics constituted significant barriers to HIV testing in Côte d'Ivoire in 2005, with gender specificities. Such barriers are substantially reduced when testing was proposed in the framework of antenatal care. This suggests that provider-initiated testing strategies may help overcome individual barriers to HIV testing.

Real-time oxide evolution of copper protected by graphene and boron nitride barriers

DEFF Research Database (Denmark)

Galbiati, Miriam; Stoot, Adam Carsten; Mackenzie, David

2017-01-01

and material science. Owing to their different electronic properties (graphene is a semimetal, whereas hBN is a wide-bandgap insulator), their protection behaviour is distinctly different. Here we investigate the performance of graphene and hBN as barrier coatings applied on copper substrates through a real......-time study in two different oxidative conditions. Our findings show that the evolution of the copper oxidation is remarkably different for the two coating materials.......Applying protective or barrier layers to isolate a target item from the environment is a common approach to prevent or delay its degradation. The impermeability of two-dimensional materials such as graphene and hexagonal boron nitride (hBN) has generated a great deal of interest in corrosion...

Real-time oxide evolution of copper protected by graphene and boron nitride barriers.

Science.gov (United States)

Galbiati, M; Stoot, A C; Mackenzie, D M A; Bøggild, P; Camilli, L

2017-01-09

Applying protective or barrier layers to isolate a target item from the environment is a common approach to prevent or delay its degradation. The impermeability of two-dimensional materials such as graphene and hexagonal boron nitride (hBN) has generated a great deal of interest in corrosion and material science. Owing to their different electronic properties (graphene is a semimetal, whereas hBN is a wide-bandgap insulator), their protection behaviour is distinctly different. Here we investigate the performance of graphene and hBN as barrier coatings applied on copper substrates through a real-time study in two different oxidative conditions. Our findings show that the evolution of the copper oxidation is remarkably different for the two coating materials.

Non-Saccharomyces yeasts protect against epithelial cell barrier disruption induced by Salmonella enterica subsp. enterica serovar Typhimurium.

Science.gov (United States)

Smith, I M; Baker, A; Arneborg, N; Jespersen, L

2015-11-01

The human gastrointestinal epithelium makes up the largest barrier separating the body from the external environment. Whereas invasive pathogens cause epithelial barrier disruption, probiotic micro-organisms modulate tight junction regulation and improve epithelial barrier function. In addition, probiotic strains may be able to reduce epithelial barrier disruption caused by pathogenic species. The aim of this study was to explore non-Saccharomyces yeast modulation of epithelial cell barrier function in vitro. Benchmarking against established probiotic strains, we evaluated the ability of four nonpathogenic yeast species to modulate transepithelial electrical resistance (TER) across a monolayer of differentiated human colonocytes (Caco-2 cells). Further, we assessed yeast modulation of a Salmonella Typhimurium-induced epithelial cell barrier function insult. Our findings demonstrate distinct patterns of non-Saccharomyces yeast modulation of epithelial cell barrier function. While the established probiotic yeast Saccharomyces boulardii increased TER across a Caco-2 monolayer by 30%, Kluyveromyces marxianus exhibited significantly stronger properties of TER enhancement (50% TER increase). In addition, our data demonstrate significant yeast-mediated modulation of Salmonella-induced epithelial cell barrier disruption and identify K. marxianus and Metschnikowia gruessii as two non-Saccharomyces yeasts capable of protecting human epithelial cells from pathogen invasion. This study demonstrates distinct patterns of non-Saccharomyces yeast modulation of epithelial cell barrier function in vitro. Further, our data demonstrate significant yeast-mediated modulation of Salmonella Typhimurium-induced epithelial cell barrier disruption and identify Kluyveromyces marxianus and Metschnikowia gruessii as two non-Saccharomyces yeasts capable of protecting human epithelial cells from pathogen invasion. This study is the first to demonstrate significant non-Saccharomyces yeast

Xyloglucan, a Plant Polymer with Barrier Protective Properties over the Mucous Membranes: An Overview

Directory of Open Access Journals (Sweden)

Núria Piqué

2018-02-01

Full Text Available Disruption of the epithelial barrier function has been recently associated with a variety of diseases, mainly at intestinal level, but also affecting the respiratory epithelium and other mucosal barriers. Non-pharmacological approaches such as xyloglucan, with demonstrated protective barrier properties, are proposed as new alternatives for the management of a wide range of diseases, for which mucosal disruption and, particularly, tight junction alterations, is a common characteristic. Xyloglucan, a natural polysaccharide derived from tamarind seeds, possesses a “mucin-like” molecular structure that confers mucoadhesive properties, allowing xyloglucan formulations to act as a barrier capable of reducing bacterial adherence and invasion and to preserve tight junctions and paracellular flux, as observed in different in vitro and in vivo studies. In clinical trials, xyloglucan has been seen to reduce symptoms of gastroenteritis in adults and children, nasal disorders and dry eye syndrome. Similar mucosal protectors containing reticulated proteins have also been useful for the treatment of irritable bowel syndrome and urinary tract infections. The role of xyloglucan in other disorders with mucosal disruption, such as dermatological or other infectious diseases, deserves further research. In conclusion, xyloglucan, endowed with film-forming protective barrier properties, is a safe non-pharmacological alternative for the management of different diseases, such as gastrointestinal and nasal disorders.

Mechanism of protection of transepithelial barrier function by Lactobacillus salivarius: strain dependence and attenuation by bacteriocin production.

Science.gov (United States)

Miyauchi, Eiji; O'Callaghan, John; Buttó, Ludovica F; Hurley, Gráinne; Melgar, Silvia; Tanabe, Soichi; Shanahan, Fergus; Nally, Kenneth; O'Toole, Paul W

2012-11-01

Enhanced barrier function is one mechanism whereby commensals and probiotic bacteria limit translocation of foreign antigens or pathogens in the gut. However, barrier protection is not exhibited by all probiotic or commensals and the strain-specific molecules involved remain to be clarified. We evaluated the effects of 33 individual Lactobacillus salivarius strains on the hydrogen peroxide (H(2)O(2))-induced barrier impairment in human epithelial Caco-2 cells. These strains showed markedly different effects on H(2)O(2)-induced reduction in transepithelial resistance (TER). The effective strains such as UCC118 and CCUG38008 attenuated H(2)O(2)-induced disassembly and relocalization of tight junction proteins, but the ineffective strain AH43324 did not. Strains UCC118 and CCUG38008 induced phosphorylation of extracellular signal-regulated kinase (ERK) in Caco-2 cells, and the ERK inhibitor U0126 attenuated the barrier-protecting effect of these strains. In contrast, the AH43324 strain induced phosphorylation of Akt and p38, which was associated with an absence of a protective effect. Global transcriptome analysis of UCC118 and AH43324 revealed that some genes in a bacteriocin gene cluster were upregulated in AH43324 under TER assay conditions. A bacteriocin-negative UCC118 mutant displayed significantly greater suppressive effect on H(2)O(2)-induced reduction in TER compared with wild-type UCC118. The wild-type strain augmented H(2)O(2)-induced phosphorylation of Akt and p38, whereas a bacteriocin-negative UCC118 mutant did not. These observations indicate that L. salivarius strains are widely divergent in their capacity for barrier protection, and this is underpinned by differences in the activation of intracellular signaling pathways. Furthermore, bacteriocin production appears to have an attenuating influence on lactobacillus-mediated barrier protection.

An investigation of bergmounds as analogs to erosion control factors on protective barriers

International Nuclear Information System (INIS)

Chamness, M.A.

1993-09-01

Included in several of the final disposal strategies proposed in the Interim Hanford Waste Management Plan (DOE-RL 1986a) is design of a protective barrier to isolate the underlying waste sites from the environment. The conceptual protective barrier design requires a fine-grained sediment to retain precipitation near the top of the barrier where evapotranspiration can recycle the moisture back into the atmosphere. The design incorporates gravel into the topsoil as one way to reduce its erosion. Information is needed to determine the optimal ratio of gravel to topsoil needed to reduce erosion without significantly reducing evapotranspiration, and its effect on erosion. Bergmounds are mounds with a gravelly surface that were formed about 13,000 years ago and represent natural analogs to the topsoil portion of the protective barrier. The primary goal of this study was to identify characteristics of bergmounds and the effects of these characteristics, especially the gravelly surface, on the amount and rate of erosion. A secondary goal was to apply a technique normally used to estimate vegetation cover to measure percent gravel cover, and to compare this technique with particle size distribution based on weight percent. Four bergmounds were investigated for this study, two in a windy site and two in a more sheltered site. Each bergmound was sampled in eight locations. Two methods were used to estimate the amount of surface gravel: the ocular point-intercept method which estimates the percent gravel cover, and sieved samples of the surface sediments which measure the percent gravel by weight. Holes were dug at each bergmound's eight sampling sites to examine and sample the subsurface sediments

Thiolated silicone oils as adhesive skin protectants for improved barrier function.

Science.gov (United States)

Partenhauser, A; Zupančič, O; Rohrer, J; Bonengel, S; Bernkop-Schnürch, A

2016-06-01

The purpose of this study was the evaluation of thiolated silicone oil as novel skin protectant exhibiting prolonged residence time, enhanced barrier function and reinforced occlusivity. Two silicone conjugates were synthesized with mercaptopropionic acid (MPA) and thioglycolic acid (TGA) as thiol ligands. Adhesion, protection against artificial urine and water vapour permeability with both a Payne cup set-up and transepidermal water loss (TEWL) measurements on porcine skin were assessed. Silicone thiomers showed pronounced substantivity on skin with 22.1 ± 6.3% and 39.2 ± 6.7% remaining silicone after 8 h for silicone-TGA and silicone-MPA, respectively, whereas unmodified silicone oil and dimethicone were no longer detectable. In particular, silicone-MPA provided a protective shield against artificial urine penetration with less than 25% leakage within 6 h. An up to 2.5-fold improved water vapour impermeability for silicone-MPA in comparison with unmodified control was discovered with the Payne cup model. In addition, for silicone-MPA a reduced TEWL by two-thirds corresponding to non-thiolated control was determined for up to 8 h. Thiolation of silicone oil leads to enhanced skin adhesiveness and barrier function, which is a major advantage compared to commonly used silicones and might thus be a promising treatment modality for various topical applications. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Promoting Barrier Performance and Cathodic Protection of Zinc-Rich Epoxy Primer via Single-Layer Graphene

Directory of Open Access Journals (Sweden)

Jingrong Liu

2018-05-01

Full Text Available The effect of single-layer graphene sheets (Gr on the corrosion protection of zinc-rich epoxy primers (ZRPs was investigated. Scanning electron microscopy (SEM with an energy dispersive spectrometer (EDS were used to characterize morphology and composition of the coatings after immersion for 25 days. The cross-sectional SEM images and X-ray photoelectron spectroscopy (XPS confirmed that the addition of single-layer graphene facilitated assembling of zinc oxides on the interface between the coating and the steel. The open circuit potential (OCP, electrochemical impedance spectroscopy (EIS measurements revealed that both the cathodic protection and barrier performance of the ZRP were enhanced after addition of 0.6 wt. % Gr (Gr0.6-ZRP. In addition, the cathodic protection property of the Gr0.6-ZRP was characterized quantitatively by localized electrochemical impedance spectroscopy (LEIS in the presence of an artificial scratch on the coating. The results demonstrate that moderate amounts of single-layer graphene can significantly improve corrosion resistance of ZRP, due to the barrier protection and cathodic protection effects.

Field study plan for alternate barriers

International Nuclear Information System (INIS)

Freeman, H.D.; Gee, G.W.; Relyea, J.F.

1989-05-01

Pacific Northwest Laboratory (PNL) is providing technical assistance in selecting, designing, evaluating, and demonstrating protective barriers. As part of this technical assistance effort, asphalt, clay, and chemical grout will be evaluated for use as alternate barriers. The purpose of the subsurface layer is to reduce the likelihood that extreme events (i.e., 100-year maximum storms, etc.) will cause significant drainage through the barrier. The tests on alternate barriers will include laboratory and field analysis of the subsurface layer performance. This field test plan outlines the activities required to test and design subsurface moisture barriers. The test plan covers activities completed in FY 1988 and planned through FY 1992 and includes a field-scale test of one or more of the alternate barriers to demonstrate full-scale application techniques and to provide performance data on a larger scale. Tests on asphalt, clay, and chemical grout were initiated in FY 1988 in small (30.5 cm diameter) tube-layer lysimeters. The parameters used for testing the materials were different for each one. The tests had to take into account the differences in material characteristics and response to change in conditions, as well as information provided by previous studies. 33 refs., 8 figs., 1 tab

Barriers to HIV testing for migrant black Africans in Western Europe

NARCIS (Netherlands)

Fakoya, A.; Reynolds, R.; Caswell, G.; Shiripinda, I.

2008-01-01

Migrant black Africans are disproportionately affected by HIV in Western Europe; we discuss the barriers to HIV testing for sub-Saharan migrants, with particular emphasis on the UK and the Netherlands. Cultural, social and structural barriers to testing, such as access to testing and care, fear of

Evaluation of biofilm performance as a protective barrier against biocorrosion using an enzyme electrode.

Science.gov (United States)

Soleimani, S; Ormeci, B; Isgor, O B; Papavinasam, S

2011-01-01

Sulfide is known to be an important factor in microbiologically influenced corrosion (MIC) of metals and concrete deterioration in wastewater treatment structures and sewer pipelines. A sulfide biosensor was used to determine the effectiveness of Escherichia coli DH5 alpha biofilm as a protective barrier against MIC. The biofilm was shown to be effective in protecting surfaces from sulfide and helping to reduce MIC using amperometric measurements. The results also indicated that the growth conditions of E. coli DH5 alpha may have an impact on the performance of the biofilm as a sulfide barrier. The simple method provided in this work enables the comparison of several microbial biofilms and selection of the ones with potential to prevent MIC in a relatively short time.

Durability and Design Issues of Thermal/environmental Barrier Coatings on Sic/sic Ceramic Matrix Composites Under 1650 C Test Conditions

Science.gov (United States)

Zhu, Dong-Ming; Choi, Sung R.; Ghosn, Louis J.; Miller, Robert A.

2004-01-01

Ceramic thermal/environmental barrier coatings for SiC-based ceramics will play an increasingly important role in future gas turbine engines because of their ability to effectively protect the engine components and further raise engine temperatures. However, the coating durability remains a major concern with the ever-increasing temperature requirements. Currently, advanced T/EBC systems, which typically include a high temperature capable zirconia- (or hahia-) based oxide top coat (thermal barrier) on a less temperature capable mullite/barium-strontium-aluminosilicate (BSAS)/Si inner coat (environmental barrier), are being developed and tested for higher temperature capability Sic combustor applications. In this paper, durability of several thermal/environmental barrier coating systems on SiC/SiC ceramic matrix composites was investigated under laser simulated engine thermal gradient cyclic, and 1650 C (3000 F) test conditions. The coating cracking and delamination processes were monitored and evaluated. The effects of temperature gradients and coating configurations on the ceramic coating crack initiation and propagation were analyzed using finite element analysis (FEA) models based on the observed failure mechanisms, in conjunction with mechanical testing results. The environmental effects on the coating durability will be discussed. The coating design approach will also be presented.

The Development of HfO2-Rare Earth Based Oxide Materials and Barrier Coatings for Thermal Protection Systems

Science.gov (United States)

Zhu, Dongming; Harder, Bryan James

2014-01-01

Advanced hafnia-rare earth oxides, rare earth aluminates and silicates have been developed for thermal environmental barrier systems for aerospace propulsion engine and thermal protection applications. The high temperature stability, low thermal conductivity, excellent oxidation resistance and mechanical properties of these oxide material systems make them attractive and potentially viable for thermal protection systems. This paper will focus on the development of the high performance and high temperature capable ZrO2HfO2-rare earth based alloy and compound oxide materials, processed as protective coating systems using state-or-the-art processing techniques. The emphasis has been in particular placed on assessing their temperature capability, stability and suitability for advanced space vehicle entry thermal protection systems. Fundamental thermophysical and thermomechanical properties of the material systems have been investigated at high temperatures. Laser high-heat-flux testing has also been developed to validate the material systems, and demonstrating durability under space entry high heat flux conditions.

Climate change disables coral bleaching protection on the Great Barrier Reef.

Science.gov (United States)

Ainsworth, Tracy D; Heron, Scott F; Ortiz, Juan Carlos; Mumby, Peter J; Grech, Alana; Ogawa, Daisie; Eakin, C Mark; Leggat, William

2016-04-15

Coral bleaching events threaten the sustainability of the Great Barrier Reef (GBR). Here we show that bleaching events of the past three decades have been mitigated by induced thermal tolerance of reef-building corals, and this protective mechanism is likely to be lost under near-future climate change scenarios. We show that 75% of past thermal stress events have been characterized by a temperature trajectory that subjects corals to a protective, sub-bleaching stress, before reaching temperatures that cause bleaching. Such conditions confer thermal tolerance, decreasing coral cell mortality and symbiont loss during bleaching by over 50%. We find that near-future increases in local temperature of as little as 0.5°C result in this protective mechanism being lost, which may increase the rate of degradation of the GBR. Copyright © 2016, American Association for the Advancement of Science.

Evaluation of Defects of Thermal Barrier Coatings by Thermal Shock Test Using Eddy Current Testing

Energy Technology Data Exchange (ETDEWEB)

Heo, Tae Hoon; Cho, Youn Ho; Lee, Joon Hyun [Pusan National University, Busan (Korea, Republic of); Oh, Jeong Seok; Lee, Koo Hyun [KIMM, Daejeon (Korea, Republic of)

2009-10-15

Periodical thermal shock can introduce defects in thermal barrier coating made by layers of CoNiCrAlY bond coating(BC) and ZrO{sub 2}-8wt%Y{sub 2}O{sub 3} ceramic top coating(TC) on Inconel-738 substrate using plasma spraying. Thermal shock test is performed by severe condition that is to heat until 1000 .deg. C and cool until 20 .deg. C. As the number of cycle is increased, the fatigue by thermal shock is also increased. After test, the micro-structures and mechanical characteristics of thermal barrier coating were investigated by SEM, XRD. The TGO layer of is Al{sub 2}O{sub 3} formed between BC and TC by periodical thermal shock test, and its change in thickness is inspected by eddy current test(ECT). By ECT test, it is shown that TGO and micro-crack can be detected and it is possible to predict the life of thermal barrier coating

Gravel admix, vegetation, and soil water interactions in protective barriers: Experimental design, construction, and initial conditions

International Nuclear Information System (INIS)

Waugh, W.J.

1989-05-01

The purpose of this study is to measure the interactive effects of gravel admix and greater precipitation on soil water storage and plant abundance. The study is one of many tasks in the Protective Barrier Development Program for the disposal of Hanford defense waste. A factorial field-plot experiment was set up at the site selected as the borrow area for barrier topsoil. Gravel admix, vegetation, and enhanced precipitation treatments were randomly assigned to the plots using a split-split plot design structure. Changes in soil water storage and plant cover were monitored using neutron probe and point intercept methods, respectively. The first-year results suggest that water extraction by plants will offset gravel-caused increases in soil water storage. Near-surface soil water contents were much lower in graveled plots with plants than in nongraveled plots without plants. Large inherent variability in deep soil water storage masked any effects gravel may have had on water content below the root zone. In the future, this source of variation will be removed by differencing monthly data series and testing for changes in soil water storage. Tests of the effects of greater precipitation on soil water storage were inconclusive. A telling test will be possible in the spring of 1988, following the first wet season during which normal precipitation is doubled. 26 refs., 9 figs., 9 tabs

Barriers to workplace HIV testing in South Africa: a systematic review of the literature.

Science.gov (United States)

Weihs, Martin; Meyer-Weitz, Anna

2016-01-01

Low workplace HIV testing uptake makes effective management of HIV and AIDS difficult for South African organisations. Identifying barriers to workplace HIV testing is therefore crucial to inform urgently needed interventions aimed at increasing workplace HIV testing. This study reviewed literature on workplace HIV testing barriers in South Africa. Pubmed, ScienceDirect, PsycInfo and SA Publications were systematically researched. Studies needed to include measures to assess perceived or real barriers to participate in HIV Counselling and Testing (HCT) at the workplace or discuss perceived or real barriers of HIV testing at the workplace based on collected data, provide qualitative or quantitative evidence related to the research topic and needed to refer to workplaces in South Africa. Barriers were defined as any factor on economic, social, personal, environmental or organisational level preventing employees from participating in workplace HIV testing. Four peer-reviewed studies were included, two with quantitative and two with qualitative study designs. The overarching barriers across the studies were fear of compromised confidentiality, being stigmatised or discriminated in the event of testing HIV positive or being observed participating in HIV testing, and a low personal risk perception. Furthermore, it appeared that an awareness of an HIV-positive status hindered HIV testing at the workplace. Further research evidence of South African workplace barriers to HIV testing will enhance related interventions. This systematic review only found very little and contextualised evidence about workplace HCT barriers in South Africa, making it difficult to generalise, and not really sufficient to inform new interventions aimed at increasing workplace HCT uptake.

Evaportranspiration studies for protective barriers: FY 1989 status report

International Nuclear Information System (INIS)

Link, S.O.; Thiede, M.E.; Downs, J.L.; Lettau, D.J.; Waugh, W.J.

1992-05-01

This document describes the results of technological developments and experiments at the Small Tube Lysimeter Facility. The objective of this research is to develop the capability to predict evapotranspiration in support of studies of water infiltration control for the Hanford Protective Barrier Development Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. This process must be predictable to adequately model soil water dynamics. We develop a miniature greenhouse (gas exchange chamber), where internal temperature and relative humidity can be controlled. With this device we measured evapotranspiration, transpiration, and carbon dioxide exchange rates from lysimeters with various surface and plant characteristics. We tested the effect on gas exchange rates and sand, gravel, admix, and soil surfaces in lysimeters where, cheat-grass, Bromus tectorum, had been seeded. Results showed that evapotranspiration was unaffected by the surface treatments. Estimated transpiration rates were higher for plants growing in sand compared with rates for plants growing in the admix and soil treatments. Soil evaporation rates were higher in the gravel treatment than in the sand treatment. Future research will entail parameterization of relationships between evapotranspiration, transpiration, soil evaporation, carbon dioxide exchange, and the abiotic and biotic factors that drive these processes for model development

Acceptance test procedure for the 105-KW isolation barrier leak rate

International Nuclear Information System (INIS)

McCracken, K.J.

1995-01-01

This acceptance test procedure shall be used to: First establish a basin water loss rate prior to installation of the two isolation barriers between the main basin and the discharge chute in K-Basin West. Second, perform an acceptance test to verify an acceptable leakage rate through the barrier seals. This Acceptance Test Procedure (ATP) has been prepared in accordance with CM-6-1 EP 4.2, Standard Engineering Practices

Physical protection

International Nuclear Information System (INIS)

Myre, W.C.; DeMontmollin, J.M.

1989-01-01

Serious concern about physical protection of nuclear facilities began around 1972. R and D was initiated at Sandia National Laboratories which had developed techniques to protect weapons for many years. Special vehicles, convoy procedures, and a communications system previously developed for weapons shipments were improved and extended for shipments of other sensitive materials. Barriers, perimeter alarms, portal and internal control systems were developed, tested, and published in handbooks and presented at symposia. Training programs were initiated for U.S. and foreign personnel. Containment and surveillance techniques were developed for the IAEA. Presently emphasis is on computer security, active barriers, and techniques to prevent theft or sabotage by ''insiders''

HIV testing implementation in two urban cities: practice, policy, and perceived barriers.

Directory of Open Access Journals (Sweden)

Camden J Hallmark

Full Text Available Although funding has supported the scale up of routine, opt-out HIV testing in the US, variance in implementation mechanisms and barriers in high-burden jurisdictions remains unknown.We conducted a survey of health care organizations in Washington, DC and Houston/Harris County to determine number of HIV tests completed in 2011, policy and practices associated with HIV testing, funding mechanisms, and reported barriers to testing in each jurisdiction and to compare results between jurisdictions.In 2012, 43 Houston and 35 DC HIV-testing organizations participated in the survey. Participants represented 85% of Department of Health-supported testers in DC and 90% of Department of Health-supported testers in Houston. The median number of tests per organization was 568 in DC and 1045 in Houston. Approximately 50% of organizations in both DC and Houston exclusively used opt-in consent and most conducted both pre- and post-test counseling with HIV testing (80% of organizations in DC, 70% in Houston. While the most frequent source of funding in DC was the Department of Health, Houston organizations primarily billed the patient or third-party payers. Barriers to testing most often reported were lack of funding, followed by patient discomfort/refusal with more barriers reported in DC.Given unique policies, resources and programmatic contexts, DC and Houston have taken different approaches to support routine testing. Many organizations in both cities reported opt-in consent approaches and pre-test counseling, suggesting 2006 national HIV testing recommendations are not being followed consistently. Addressing the barriers to testing identified in each jurisdiction may improve expansion of testing.

Practical protective tools for occupational exposure: 1) double focus spectacles for the aged with highly refracted glass lens 2) remodeled barrier for radiation protection.

Science.gov (United States)

Kurokawa, S; Yabe, S; Takamura, A; Ishizaki, H; Aizawa, S

2000-11-30

Two practical protective tools for occupational exposure for neurointerventional radiologists are presented. The first purpose of this study was to investigate the effectiveness of double focus spectacles for the aged with a highly refracted glass lens (special spectacles for the aged) for radiation protection of the crystalline lens of the eye in comparison with other spectacles on the market, based on the measurement of film density which was obtained by exposure of X-ray through those spectacles. As a result of the film densitometry mentioned above, the effectiveness of special spectacles for the aged in radiation protection was nearly equal to the effectiveness of a goggle type shield which is made with a 0.07 mm lead-equivalent plastic lens. The second purpose of this study was to investigate the effectiveness of the protective barrier, which we remodeled for cerebral angiography or neuroendovascular therapy, for radiation exposure, based on the measurement in a simulated study with a head phantom, and on the measurement of radiation exposure in operaters during procedures of clinical cases. In the experimental study radiation exposure in supposed position of the crystalline lens was reduced to about one third and radiation exposure in supposed position of the gonadal glands was reduced to about one seventh, compared to radiation exposure without employing the barrier. The radiation exposure was monitored at the left breast of three radiologists, in 215 cases of cerebral angiography. Employing the barrier in cerebral angiography, average equivalent dose at the left breast measured 1.49mu Sv during 10 min of fluoroscopy. In three kinds of neuroendovascular therapy in 40 cases, radiation exposure in an operator was monitored in the same fashion and the dose was recorded less than the result reported in previous papers in which any protective barrier have not been employed in the procedure (1,2). As a result, the two above mentioned protective tools are

Introducing Meta-models for a More Efficient Hazard Mitigation Strategy with Rockfall Protection Barriers

Science.gov (United States)

Toe, David; Mentani, Alessio; Govoni, Laura; Bourrier, Franck; Gottardi, Guido; Lambert, Stéphane

2018-04-01

The paper presents a new approach to assess the effecctiveness of rockfall protection barriers, accounting for the wide variety of impact conditions observed on natural sites. This approach makes use of meta-models, considering a widely used rockfall barrier type and was developed from on FE simulation results. Six input parameters relevant to the block impact conditions have been considered. Two meta-models were developed concerning the barrier capability either of stopping the block or in reducing its kinetic energy. The outcome of the parameters range on the meta-model accuracy has been also investigated. The results of the study reveal that the meta-models are effective in reproducing with accuracy the response of the barrier to any impact conditions, providing a formidable tool to support the design of these structures. Furthermore, allowing to accommodate the effects of the impact conditions on the prediction of the block-barrier interaction, the approach can be successfully used in combination with rockfall trajectory simulation tools to improve rockfall quantitative hazard assessment and optimise rockfall mitigation strategies.

Mass media barriers to social marketing interventions: the example of sun protection in the UK.

Science.gov (United States)

Kemp, Gillian Ann; Eagle, Lynne; Verne, Julia

2011-03-01

The role of the mass media in communicating health-related information to the wider population is the focus of this paper. Using the example of sun protection within the UK, we highlight some of the major challenges to raising awareness of steadily increasing melanoma rates and of effective sun protection strategies. The implications of potential barriers to official sun protection messages via conflicting messages in the media are discussed in terms of editorial on sun protection and in the way in which television programme content portrays the issues. Implications for public policy and future research conclude the paper.

Motivators and barriers to HIV testing among street-based female sex workers in St. Petersburg, Russia.

Science.gov (United States)

King, Elizabeth J; Maman, Suzanne; Dudina, Victoria I; Moracco, Kathryn E; Bowling, J Michael

2017-07-01

Female sex workers are particularly susceptible to HIV-infection in Russia. However, a dearth of information exists on their utilisation of HIV services. A mixed-methods, cross-sectional study was conducted to examine motivators and barriers to HIV testing among street-based sex workers in St. Petersburg, Russia. The health belief model was the theoretical framework for the study. Twenty-nine sex workers participated in in-depth interviews, and 139 sex workers completed interviewer-administered surveys between February and September 2009. Barriers to getting an HIV test were fear of learning the results, worrying that other people would think they were sick, and the distance needed to travel to obtain services. Motivators for getting tested were protecting others from infection, wanting to know one's status and getting treatment if diagnosed. Logistic regression analysis demonstrated that knowing people living with HIV [aOR = 6.75, 95% CI (1.11, 41.10)] and length of time since start of injection drug use [aOR = 0.30, 95% CI (0.09, 0.97)] were significantly associated with recently getting tested. These results are important to consider when developing public health interventions to help female sex workers in Russia learn their HIV status and get linked to care and treatment services if needed.

TECHNICAL BASIS FOR EVALUATING SURFACE BARRIERS TO PROTECT GROUNDWATER FROM DEEP VADOSE ZONE CONTAMINATION

International Nuclear Information System (INIS)

Fayer, J.M.; Freedman, V.L.; Ward, A.L.; Chronister, G.B.

2010-01-01

geophysical approaches for delineating subsurface plumes and monitoring their migration in the deep vadose zone. (4) Controlled Field Test at Sisson and Lu Site - Evaluate the ability ofthe model to predict long-term liquid, vapor, and chemical transport processes at a well-characterized site containing a plume of subsurface water and tracer remaining from injections in the early 1980s and 2000s. (5) Deep Vadose Zone Monitoring at T Farm - Demonstrate the ability of the geophysical sensors and the model to detect and predict long-term migration of liquid and vapor between the vadose zone beneath the infiltration area and the vadose zone protected by the interim cover. (6) Deep Vadose Zone Monitoring at the Prototype Hanford Barrier - Demonstrate the ability of geophysical sensors and the model to detect and predict the hydrologic conditions in the vadose zone beneath the Prototype Hanford Barrier 15 years after construction.

Glovebox characterization and barrier integrity testing using fluorescent powder

International Nuclear Information System (INIS)

Wahlquist, D.R.

1996-01-01

This paper presents a method for characterizing the spread of contamination and testing the barrier integrity of a new glovebox during material transfer operations and glove change-outs using fluorescent powder. Argonne National Laboratory-West has performed this test on several new gloveboxes prior to putting them into service. The test is performed after the glovebox has been leak tested and all systems have been verified to be operational. The purpose of the test is to show that bag-in/bag-out operations and glove change-outs can be accomplished without spreading the actual contaminated material to non-contaminated areas. The characterization test also provides information as to where contamination might be expected to build-up during actual operations. The fluorescent powder is used because it is easily detectable using an ultra-violet light and disperses in a similar fashion to radioactive material. The characterization and barrier integrity test of a glovebox using fluorescent powder provides a visual method of determining areas of potential contamination accumulation and helps evaluate the ability to perform clean transfer operations and glove change-outs

Movable scour protection. Model test report

Energy Technology Data Exchange (ETDEWEB)

Lorenz, R.

2002-07-01

This report presents the results of a series of model tests with scour protection of marine structures. The objective of the model tests is to investigate the integrity of the scour protection during a general lowering of the surrounding seabed, for instance in connection with movement of a sand bank or with general subsidence. The scour protection in the tests is made out of stone material. Two different fractions have been used: 4 mm and 40 mm. Tests with current, with waves and with combined current and waves were carried out. The scour protection material was placed after an initial scour hole has evolved in the seabed around the structure. This design philosophy has been selected because the situation often is that the scour hole starts to generate immediately after the structure has been placed. It is therefore difficult to establish a scour protection at the undisturbed seabed if the scour material is placed after the main structure. Further, placing the scour material in the scour hole increases the stability of the material. Two types of structure have been used for the test, a Monopile and a Tripod foundation. Test with protection mats around the Monopile model was also carried out. The following main conclusions have emerged form the model tests with flat bed (i.e. no general seabed lowering): 1. The maximum scour depth found in steady current on sand bed was 1.6 times the cylinder diameter, 2. The minimum horizontal extension of the scour hole (upstream direction) was 2.8 times the cylinder diameter, corresponding to a slope of 30 degrees, 3. Concrete protection mats do not meet the criteria for a strongly erodible seabed. In the present test virtually no reduction in the scour depth was obtained. The main problem is the interface to the cylinder. If there is a void between the mats and the cylinder, scour will develop. Even with the protection mats that are tightly connected to the cylinder, scour is expected to develop as long as the mats allow for

Design and testing of 45 kV, 50 kHz pulse power supply for dielectric barrier discharges

Science.gov (United States)

Sharma, Surender Kumar; Shyam, Anurag

2016-10-01

The design, construction, and testing of high frequency, high voltage pulse power supply are reported. The purpose of the power supply is to generate dielectric barrier discharges for industrial applications. The power supply is compact and has the advantage of low cost, over current protection, and convenient control for voltage and frequency selection. The power supply can generate high voltage pulses of up to 45 kV at the repetitive frequency range of 1 kHz-50 kHz with 1.2 kW input power. The output current of the power supply is limited to 500 mA. The pulse rise time and fall time are less than 2 μs and the pulse width is 2 μs. The power supply is short circuit proof and can withstand variable plasma load conditions. The power supply mainly consists of a half bridge series resonant converter to charge an intermediate capacitor, which discharges through a step-up transformer at high frequency to generate high voltage pulses. Semiconductor switches and amorphous cores are used for power modulation at higher frequencies. The power supply is tested with quartz tube dielectric barrier discharge load and worked stably. The design details and the performance of the power supply on no load and dielectric barrier discharge load are presented.

Evaluation of skin surface hydration state and barrier function of stratum corneum of dorsa of hands and heels treated with PROTECT X2 skin protective cream.

Science.gov (United States)

Kubota, Takahiro

2012-06-01

Skin roughness is a term commonly used in Japan to describe a poor skin condition related to a rough and dry skin surface that develops as a result of various damaging effects from the environment or skin inflammation. Recovery from skin roughness requires skin care for a long period, thus it is important to prevent development of such skin changes. PROTECT X2 contains agents used for a protective covering of the skin from frequent hand washing or use of alcohol-based disinfectants. These unique components are also thought to be effective to treat skin roughness of the dorsa of the hands and heels. In the present study, we evaluated the effectiveness of PROTECT X2 to increase skin surface hydration state, as well as enhance the barrier function of the stratum corneum of the dorsa of the hands and heels in elderly individuals. A total of 8 elderly subjects and their caretakers without any skin diseases participated in the study. They applied PROTECT X2 by themselves to the dorsum area of 1 hand and heel 3 to 5 times daily for 1 month, while the opposite sides were left untreated. We measured stratum corneum (SC) hydration and transepidermal water loss (TEWL) before beginning treatment, then 1 week and 1 month after the start of treatment to compare between the treated and untreated skin. SC hydration state after applications of PROTECT X2 was 1.5- to 3.0-fold higher than that of the untreated skin in the dorsa of both hands and heels, indicating that the moisturizing ingredients accompanied by water were replenished in those areas where the cream was applied. Also, TEWL in the dorsum of the hands was 17.0-27.9% lower on the treated side, indicating improvement in SC barrier function. On the basis of these findings, we concluded that PROTECT X2 enhances water-holding in the SC and aids the barrier function of the skin in the dorsum of the hands. In addition, we consider that this formulation is useful for not only protecting the hands from the effects of such agents

Systematic approach in protection and ergonomics testing personal protective equipment

NARCIS (Netherlands)

Hartog. E.A. den

2009-01-01

In the area of personal protection against chemical and biological (CB) agents there is a strong focus on testing the materials against the relevant threats. The testing programs in this area are elaborate and are aimed to guarantee that the material protects according to specifications. This

Horizontal insulating barriers as a way to protect groundwater

Science.gov (United States)

Cicha-Szot, Renata; Labus, Krzysztof; Falkowicz, Sławomir; Madetko, Norbert

2018-06-01

Trenchless Technology of Forming Horizontal Insulating Barriers (TFHB) can be considered a method of groundwater protection against inflow of pollutants. In TFHB technology, the working fluid (sodium silicate solution) and the gelling agent (CO2) are injected separately, using one tool, to different zones of the aquifer profile. Carbon dioxide injected into the saturation zone rises due to buoyancy forces and reaches the silicate which was injected at the water table level. This initiates the process of silicate gelation, resulting in the formation of an insulating barrier. For technological purposes, the gelation time must be controlled, and the resulting gel must have certain mechanical properties. In order to apply THFB in real conditions it was necessary to identify important technological and technical parameters, as well as to define interactions between the injected fluid and the aquifer rocks. Geochemical modelling (equilibrium, reaction path and reactive transport) was used to identify potential geochemical effects of the application of TFHB in sandy aquifers. Certain petrophysical parameters and mineralogical assemblages of aquifers were addressed, taking into account both low and strongly mineralized groundwater. The simulations revealed that TFHB does not have a negative impact on the chemistry of rock-water systems described in this work.

Prevalence of bovine brucellosis in slaughtered cattle and barriers to better protection of abattoir workers in Ibadan, South-Western Nigeria.

Science.gov (United States)

Ayoola, Modupe Comfort; Akinseye, Victor Oluwatoyin; Cadmus, Eniola; Awosanya, Emmanuel; Popoola, Olufemi Akinyele; Akinyemi, Oluwaseun Oladapo; Perrett, Lorraine; Taylor, Andrew; Stack, Judy; Moriyon, Ignacio; Cadmus, Simeon Idowu

2017-01-01

Brucellosis is a neglected zoonosis of public health importance. This study was conducted to determine the prevalence and risk factors of brucellosis among slaughtered cattle as well as challenges to the protection of abattoir workers in Nigeria. A slaughterhouse study was conducted in a major abattoir in Ibadan from March to August, 2013. To diagnose brucellosis, serum samples from 1,241 slaughtered cattle were tested using Rose-Bengal test (RBT) and competitive enzyme-linked immunosorbent assay (cELISA); again, 57 milk samples were tested with milk ring test (MRT) and indirect ELISA (iELISA). Furthermore, a survey on the usage of personal protective equipment (PPE) and challenges to its use by abattoir workers was done. Data were analysed using Stata 12. Seroprevalence by RBT was 7.8%; 77.3% (75/97) of these were corroborated by cELISA. Prevalence in milk samples by MRT and indirect ELISA were 33.3% and 3.5%, respectively. Sex (OR: 2.5; 95%CI:1.3-4.5) was the factor significantly associated with Brucella seropositivity. None of the abattoir workers used standard protective overalls; while, 99.6% of the meat handlers and 84.1% of the butchers worked barefoot. Most of the workers (75.7%) wore no protective gloves. The respondents agreed that provision of free PPE and sanctions against non-users would encourage its use. Our findings indicate moderate prevalence (7.8%) of bovine brucellosis with sex of cattle being a risk factor. A notable barrier to better protection of abattoir workers against brucellosis is perceived inconvenience arising from use of gloves. Therefore, preventive and control measures against brucellosis must include education and use of PPE among abattoir workers.

Barriers to HIV testing for migrant black Africans in Western Europe.

Science.gov (United States)

Fakoya, I; Reynolds, R; Caswell, G; Shiripinda, I

2008-07-01

Migrant black Africans are disproportionately affected by HIV in Western Europe; we discuss the barriers to HIV testing for sub-Saharan migrants, with particular emphasis on the UK and the Netherlands. Cultural, social and structural barriers to testing, such as access to testing and care, fear of death and disease and fear of stigma and discrimination in the community, can be identified. Lack of political will, restrictive immigration policies and the absence of African representation in decision-making processes are also major factors preventing black Africans from testing. HIV testing strategies need to be grounded in outreach and community mobilisation, addressing fear of diagnosis, highlighting the success of treatment and tackling HIV-related stigma among black African migrant communities.

Vibration damage testing of thermal barrier fibrous blanket insulation

International Nuclear Information System (INIS)

Black, W.E.; Betts, W.S.

1984-01-01

GA Technologies is engaged in a long-term, multiphase program to determine the vibration characteristics of thermal barrier components leading to qualification of assemblies for High Temperature Gas-Cooled Reactor (HTGR) service. The phase of primary emphasis described herein is the third in a series of acoustic tests and uses as background the more elemental tests preceding it. Two sizes of thermal barrier coverplates with one fibrous blanket insulation type were tested in an acoustic environment at sound pressure levels up to 160 dB. Three tests were conducted using sinusoidal and random noise for up to 200 h duration at room temperature. Frequent inspections were made to determine the progression of degradation using definition of stages from a prior test program. Initially the insulation surface adjacent to the metallic seal sheets (noise side) assumed a chafed or polished appearance. This was followed by flattening of the as-received pillowed surface. This stage was followed by a depression being formed in the vicinity of the free edge of the coverplate. Next, loose powder from within the blanket and from fiber erosion accumulated in the depression. Prior experience showed that the next stage of deterioration exhibited a consolidation of the powder to form a local crust. In this test series, this last stage generally failed to materialize. Instead, surface holes generated by solid ceramic particulates (commonly referred to as 'shot') constituted the stage following powdering. With the exception of some manufacturing-induced anomalies, the final stage, namely, gross fiber breakup, did not occur. It is this last stage that must be prevented for the thermal barrier to maintain its integrity. (orig./GL)

Study of araldite in edge protection of n-type and p-type surface barrier detectors

International Nuclear Information System (INIS)

Alencar, M.A.V.; Jesus, E.F.O.; Lopes, R.T.

1995-01-01

The aim of this work is the realization of a comparative study between the surface barrier detectors performance n and type using the epoxy resin Araldite as edge protection material with the purpose of determining which type of detector (n or p) the use of Araldite is more indicated. The surface barrier detectors were constructed using n and p type silicon wafer with resistivity of 3350Ω.cm and 5850 Ω.cm respectively. In the n type detectors, the metals used as ohmic and rectifier contacts were the Al and Au respectively, while in the p type detectors, the ohmic and rectifier contacts were Au and Al. All metallic contacts were done by evaporation in high vacuum (∼10 -4 Torr) and with deposit of 40 μm/cm 2 . The obtained results for the detectors (reverse current of -350nA and resolution from 21 to 26 keV for p type detectors and reserve current of 1μA and resolution from 44 to 49 keV for n type detectors) tend to demonstrate that use of epoxy resin Araldite in the edge protection is more indicated to p type surface barrier detectors. (author). 3 refs., 4 figs., 1 tab

Oral intake of beet extract provides protection against skin barrier impairment in hairless mice.

Science.gov (United States)

Kawano, Ken-Ichi; Umemura, Kazuo

2013-05-01

The epidermis acts as a functional barrier against the external environment. Disturbances in the function of this barrier cause water loss and increase the chances of penetration by various irritable stimuli, leading to skin diseases such as dry skin, atopic dermatitis, and psoriasis. Ceramides are a critical natural element of the protective epidermal barrier. The aim of this study was to evaluate whether the oral intake of beet (Beta vulgaris) extract, a natural product rich in glucosylceramide (GlcCer), may prevent disturbance in skin barrier function. When HR-1 hairless mice were fed a special diet (HR-AD), transepidermal water loss (TEWL) from the dorsal skin increased, with a compensatory increase in water intake after 5 weeks. Mice fed with HR-AD had dry skin with erythema and showed increased scratching behaviour. Histological examinations revealed a remarkable increase in the thickness of the skin at 8 weeks. Supplemental addition of beet extract, which contained GlcCer at a final concentration of 0.1%, significantly prevented an increase TEWL, water intake, cumulative scratching time, and epidermal thickness at 8 weeks. These results indicate that oral intake of beet extract shows potential for preventing skin diseases associated with impaired skin barrier function. Copyright © 2012 John Wiley & Sons, Ltd.

Non-Saccharomyces yeasts protect against epithelial cell barrier disruption induced by Salmonella enterica subsp. enterica serovar Typhimurium

DEFF Research Database (Denmark)

Smith, Ida Mosbech; Baker, A; Arneborg, Nils

2015-01-01

distinct patterns of non-Saccharomyces yeast modulation of epithelial cell barrier function. While the established probiotic yeast Saccharomyces boulardii increased TER across a Caco-2 monolayer by 30%, Kluyveromyces marxianus exhibited significantly stronger properties of TER enhancement (50% TER increase....... In addition, probiotic strains may be able to reduce epithelial barrier disruption caused by pathogenic species. The aim of this study was to explore non-Saccharomyces yeast modulation of epithelial cell barrier function in vitro. Benchmarking against established probiotic strains, we evaluated the ability......). In addition, our data demonstrate significant yeast-mediated modulation of Salmonella-induced epithelial cell barrier disruption and identify K. marxianus and Metschnikowia gruessii as two non-Saccharomyces yeasts capable of protecting human epithelial cells from pathogen invasion. SIGNIFICANCE AND IMPACT...

Vehicle barrier systems

International Nuclear Information System (INIS)

Sena, P.A.

1986-01-01

The ground vehicle is one of the most effective tools available to an adversary force. Vehicles can be used to penetrate many types of perimeter barriers, transport equipment and personnel rapidly over long distances, and deliver large amounts of explosives directly to facilities in suicide missions. The function of a vehicle barrier system is to detain or disable a defined threat vehicle at a selected distance from a protected facility. Numerous facilities are installing, or planning to install, vehicle barrier systems and many of these facilities are requesting guidance to do so adequately. Therefore, vehicle barriers are being evaluated to determine their stopping capabilities so that systems can be designed that are both balanced and capable of providing a desired degree of protection. Equally important, many of the considerations that should be taken into account when establishing a vehicle barrier system have been identified. These considerations which pertain to site preparation, barrier selection, system integration and operation, and vehicle/barrier interaction, are discussed in this paper

Gas permeability of bentonite barriers: development, construction and testing of a measurement system

Directory of Open Access Journals (Sweden)

Heraldo Nunes Pitanga

Full Text Available Abstract This article proposes a testing device to quickly and reliably estimate the gas permeability of bentonite-based clay barriers used in landfill cover systems. The testing methodology is based on a transient gas flow regime that passes through the barrier, therefore not requiring the use of sophisticated equipment that aim to maintain constant differential pressure and measure the gas flow, common requirements for testing methods under a permanent flow regime. To confirm the feasibility of the proposed technique, tests were performed on a pure hydrated bentonite layer, which subsequently encompassed samples of geosynthetic clay liner (GCL at different moisture contents. Geosynthetic clay liners are often selected as a part of the barrier layer for cover systems in solid waste landfills to prevent infiltration of rainfall and migration of biogas into the atmosphere. The results confirmed the equipment reliability and differentiate the different responses of the gas flow barriers studied, considering their different compositions and different moistures.

Ultrasonic tests on materials with protective coatings

International Nuclear Information System (INIS)

Whaley, H.L.

1977-01-01

Protective coatings are applied to some nuclear components such as reactor vessels to inhibit surface corrosion. Since in-service ultrasonic inspection is required for such components, a study was performed to determine whether the use of protective coatings can affect ultrasonic tests. Two 2 in. thick steel plates were uniformly machined, sandblasted, and used as bases for two types of protective coatings. The type and thickness of the coating and the presence of contamination, such as fingerprints or mild oxidation under the paint, were the independent variables associated with the coating. Tests were run to determine the effects of the protective coatings on ultrasonic tests conducted on the steel plates. Significant variations in ultrasonic test sensitivity occurred as a function of the type and thickness of protective coating, couplant (material that conducts the ultrasound from the transducer into the test part, normally water or some type of oil), transducer wear plate, and ultrasonic test frequency. Ultrasonic tests can be strongly affected by a protective coating on the component to be inspected. As compared to the test sensitivity for an uncoated reference sample, the sensitivity may be dramatically shifted up or down on the coated surface. In certain coating thickness ranges, the sensitivity can fluctuate widely with small changes in coating thickness. If a coating is chosen properly, however, components with protective coatings can be tested ultrasonically with valid results. These results are for the case of ultrasonic input on the coated surface. It is not expected that an ultrasonic test conducted from the front surface would be appreciably affected by a coating on the rear surface

The Field Lysimeter Test Facility (FLTF) at the Hanford Site: Installation and initial tests

International Nuclear Information System (INIS)

Gee, G.W.; Kirkham, R.R.; Downs, J.L.; Campbell, M.D.

1989-02-01

The objectives of this program are to test barrier design concepts and to demonstrate a barrier design that meets established performance criteria for use in isolating wastes disposed of near-surface at the Hanford Site. Specifically, the program is designed to assess how well the barriers perform in controlling biointrusion, water infiltration, and erosion, as well as evaluating interactions between environmental variables and design factors of the barriers. To assess barrier performance and design with respect to infiltration control, field lysimeters and small- and large-scale field plots are planned to test the performance of specific barrier designs under actual and modified (enhanced precipitation) climatic conditions. The Field Lysimeter Test Facility (FLTF) is located in the 600 Area of the Hanford Site just east of the 200 West Area and adjacent to the Hanford Meteorological Station. The FLTF data will be used to assess the effectiveness of selected protective barrier configurations in controlling water infiltration. The facility consists of 14 drainage lysimeters (2 m dia x 3 m deep) and four precision weighing lysimeters (1.5 m x 1.5 m x 1.7 m deep). The lysimeters are buried at grade and aligned in a parallel configuration, with nine lysimeters on each side of an underground instrument chamber. The lysimeters were filled with materials to simulate a multilayer protective barrier system. Data gathered from the FLTF will be used to compare key barrier components and to calibrate and test models for predicting long-term barrier performance

Field tests for assessing electrical protection performance regarding electromechanical protection relays

Directory of Open Access Journals (Sweden)

Luis Alfredo Esteves

2012-09-01

Full Text Available This article describes designing and using a series of field tests (such as pick-up test and operating characteristics aimed at ascertaining the correct operation of relays’ electromechanical protection. The characteristic elements involved in adjusting electromechanical protection relays are presented.

Hanford prototype-barrier status report: FY 1995

International Nuclear Information System (INIS)

Gee, G.W.; Ward, A.L.; Gilmore, B.G.; Ligotke, M.W.; Link, S.O.

1995-11-01

Surface barriers (or covers) have been proposed for use at the Hanford Site as a means to isolate certain waste sites that, for reasons of cost or worker safety or both, may not be exhumed. Surface barriers are intende to isolated the wastes from the accessible environment and to provide long-term protection to future populations that might use the Hanford Site. Currently, no ''proven'' long-term barrier system is available. For this reason, the Hanford Site Permanent Isolation Surface-Barrier Development Program (BDP) was organized to develop the technology needed to provide long-term surface barrier capability for the Hanford Site for the US Department of Energy (DOE). Designs have been proposed to meet the most stringent needs for long-term waste disposal. The objective of the current barrier design is to use natural materials to develop a protective barrier system that isolates wastes for at least 1000 years by limiting water, plant, animal, and human intrusion; and minimizing erosion. The design criteria for water drainage has been set at 0.5 mm/yr. While other design criteria are more qualitative, it is clear that waste isolation for an extended time is the prime objective of the design. Constructibility and performance. are issues that can be tested and dealt with by evaluating prototype designs prior to extensive construction and deployment of covers for waste sites at Hanford

A qualitative analysis of multi-level barriers to HIV testing among women in Lebanon.

Science.gov (United States)

Clark, Kirsty A; Keene, Danya E; Pachankis, John E; Fattal, Omar; Rizk, Nesrine; Khoshnood, Kaveh

2017-09-01

While the number of HIV cases in the Middle East and North Africa region is low compared to other regions, recent studies show that incidence is increasing especially among high-risk populations; in particular, little is known about women and HIV in the region. Through semi-structured interviews with sexual healthcare providers and staff at non-governmental organisations, we sought to understand barriers to HIV testing among women in Lebanon. Using snowball sampling, key informants were recruited from greater Beirut (12 physicians, 9 non-governmental organisation staff). Data were analysed using a grounded theory framework. Findings identified barriers to HIV testing among women at each level of an adapted social-ecological model (i.e. social-cultural barriers, policy barriers, interpersonal healthcare provider barriers and intrapersonal barriers). Primary findings include the culture of sex as taboo; lack of sexual health education among women; fear of disclosing HIV testing and diagnosis; financial barriers linked to stigmatising insurance policies; and provider attitudes towards women. Findings can be used to inform HIV-related sexual health interventions at multiple levels for women in Lebanon and the greater region.

Plan for metal barrier selection and testing for NNWSI

International Nuclear Information System (INIS)

Halsey, W.G.; McCright, R.D.

1987-12-01

The Department of Energy's Nevada Nuclear Waste Storage Investigations (NNWSI) Project is evaluating a site at Yucca Mountain in Nevada as a geological repository for the storage of high-level nuclear waste. The Nuclear Waste Management Projects (NWMP) at Lawrence Livermore National Laboratory (LLNL) has the responsibility for design, testing, and performance analysis of the NNWSI waste packages. One portion of this work is the selection and testing of the material for container construction. The anticipated container design is for this material to be a corrosion resistant metal called the metal barrier. This document is the publication version of the Scientific Investigation Plan (SIP) for the Metal Barrier Selection and Testing Task. The SIP serves as a formal planning document for the investigation and is used to assign quality assurance levels to the activities of the task. This document is an informal version for information distribution and has the sections on ''Schedule and Milestones'' and the ''Quality Assurance Level Assignment Sheets'' removed

The Analysis of Low Noise Protection Barriers Influence on Tram Traffic Noise Levels

Directory of Open Access Journals (Sweden)

Ahac Maja

2013-07-01

Full Text Available The paper describes the analysis of tram traffic noise situation in residential areas in the vicinity of Drzic Avenue, one of the major routes between the northern and southern part of the Croatian capital city Zagreb, and the effect of low barriers placed by the tracks on tram noise mitigation. In order to evaluate the effect of planned protection measure, noise models were produced and verified with short-term field measurements. Calculations were conducted by means of noise prediction software, using European interim noise prediction method and 3D model of analyzed area. Finally, the results of noise calculations for existing tram traffic situation and planned measure of protection are presented on noise maps.

Staged-Fault Testing of Distance Protection Relay Settings

Science.gov (United States)

Havelka, J.; Malarić, R.; Frlan, K.

2012-01-01

In order to analyze the operation of the protection system during induced fault testing in the Croatian power system, a simulation using the CAPE software has been performed. The CAPE software (Computer-Aided Protection Engineering) is expert software intended primarily for relay protection engineers, which calculates current and voltage values during faults in the power system, so that relay protection devices can be properly set up. Once the accuracy of the simulation model had been confirmed, a series of simulations were performed in order to obtain the optimal fault location to test the protection system. The simulation results were used to specify the test sequence definitions for the end-to-end relay testing using advanced testing equipment with GPS synchronization for secondary injection in protection schemes based on communication. The objective of the end-to-end testing was to perform field validation of the protection settings, including verification of the circuit breaker operation, telecommunication channel time and the effectiveness of the relay algorithms. Once the end-to-end secondary injection testing had been completed, the induced fault testing was performed with three-end lines loaded and in service. This paper describes and analyses the test procedure, consisting of CAPE simulations, end-to-end test with advanced secondary equipment and staged-fault test of a three-end power line in the Croatian transmission system.

Barrier protective effects of withaferin A in HMGB1-induced inflammatory responses in both cellular and animal models

International Nuclear Information System (INIS)

Lee, Wonhwa; Kim, Tae Hoon; Ku, Sae-Kwang; Min, Kyoung-jin; Lee, Hyun-Shik; Kwon, Taeg Kyu; Bae, Jong-Sup

2012-01-01

Withaferin A (WFA), an active compound from Withania somnifera, is widely researched for its anti-inflammatory, cardioactive and central nervous system effects. In this study, we first investigated the possible barrier protective effects of WFA against pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) and in mice induced by high mobility group box 1 protein (HMGB1) and the associated signaling pathways. The barrier protective activities of WFA were determined by measuring permeability, leukocytes adhesion and migration, and activation of pro-inflammatory proteins in HMGB1-activated HUVECs. We found that WFA inhibited lipopolysaccharide (LPS)-induced HMGB1 release and HMGB1-mediated barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of leukocytes to human endothelial cells. WFA also suppressed acetic acid-induced hyperpermeability and carboxymethylcellulose-induced leukocytes migration in vivo. Further studies revealed that WFA suppressed the production of interleukin 6, tumor necrosis factor-α (TNF-α) and activation of nuclear factor-κB (NF-κB) by HMGB1. Collectively, these results suggest that WFA protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases. -- Highlights: ► Withaferin A inhibited LPS induced HMGB1 release. ► Withaferin A reduced HMGB1-mediated hyperpermeability. ► Withaferin A inhibited HMGB1-mediated adhesion and migration of leukocytes. ► Withaferin A inhibited HMGB1-mediated activation of NF-κB, IL-6 and TNF-α.

Barrier protective effects of withaferin A in HMGB1-induced inflammatory responses in both cellular and animal models

Energy Technology Data Exchange (ETDEWEB)

Lee, Wonhwa [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University (Korea, Republic of); Kim, Tae Hoon [Department of Herbal Medicinal Pharmacology, Daegu Haany University (Korea, Republic of); Ku, Sae-Kwang [Department of Anatomy and Histology, College of Oriental Medicine, Daegu Haany University, Gyeongsan 712-715 (Korea, Republic of); Min, Kyoung-jin [Department of Immunology, School of Medicine, Keimyung University, Daegu 704-701 (Korea, Republic of); Lee, Hyun-Shik [School of Life Sciences, College of Natural Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kwon, Taeg Kyu [Department of Immunology, School of Medicine, Keimyung University, Daegu 704-701 (Korea, Republic of); Bae, Jong-Sup, E-mail: baejs@knu.ac.kr [College of Pharmacy, Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

2012-07-01

Withaferin A (WFA), an active compound from Withania somnifera, is widely researched for its anti-inflammatory, cardioactive and central nervous system effects. In this study, we first investigated the possible barrier protective effects of WFA against pro-inflammatory responses in human umbilical vein endothelial cells (HUVECs) and in mice induced by high mobility group box 1 protein (HMGB1) and the associated signaling pathways. The barrier protective activities of WFA were determined by measuring permeability, leukocytes adhesion and migration, and activation of pro-inflammatory proteins in HMGB1-activated HUVECs. We found that WFA inhibited lipopolysaccharide (LPS)-induced HMGB1 release and HMGB1-mediated barrier disruption, expression of cell adhesion molecules (CAMs) and adhesion/transendothelial migration of leukocytes to human endothelial cells. WFA also suppressed acetic acid-induced hyperpermeability and carboxymethylcellulose-induced leukocytes migration in vivo. Further studies revealed that WFA suppressed the production of interleukin 6, tumor necrosis factor-α (TNF-α) and activation of nuclear factor-κB (NF-κB) by HMGB1. Collectively, these results suggest that WFA protects vascular barrier integrity by inhibiting hyperpermeability, expression of CAMs, adhesion and migration of leukocytes, thereby endorsing its usefulness as a therapy for vascular inflammatory diseases. -- Highlights: ► Withaferin A inhibited LPS induced HMGB1 release. ► Withaferin A reduced HMGB1-mediated hyperpermeability. ► Withaferin A inhibited HMGB1-mediated adhesion and migration of leukocytes. ► Withaferin A inhibited HMGB1-mediated activation of NF-κB, IL-6 and TNF-α.

The Many Faces of Graphene as Protection Barrier. Performance under Microbial Corrosion and Ni Allergy Conditions

Science.gov (United States)

Gentil, Dana; del Campo, Valeria; Henrique Rodrigues da Cunha, Thiago; Henríquez, Ricardo; Garín, Carolina; Ramírez, Cristian; Flores, Marcos; Seeger, Michael

2017-01-01

In this work we present a study on the performance of CVD (chemical vapor deposition) graphene coatings grown and transferred on Ni as protection barriers under two scenarios that lead to unwanted metal ion release, microbial corrosion and allergy test conditions. These phenomena have a strong impact in different fields considering nickel (or its alloys) is one of the most widely used metals in industrial and consumer products. Microbial corrosion costs represent fractions of national gross product in different developed countries, whereas Ni allergy is one of the most prevalent allergic conditions in the western world, affecting around 10% of the population. We found that grown graphene coatings act as a protective membrane in biological environments that decreases microbial corrosion of Ni and reduces release of Ni2+ ions (source of Ni allergic contact hypersensitivity) when in contact with sweat. This performance seems not to be connected to the strong orbital hybridization that Ni and graphene interface present, indicating electron transfer might not be playing a main role in the robust response of this nanostructured system. The observed protection from biological environment can be understood in terms of graphene impermeability to transfer Ni2+ ions, which is enhanced for few layers of graphene grown on Ni. We expect our work will provide a new route for application of graphene as a protection coating for metals in biological environments, where current strategies have shown short-term efficiency and have raised health concerns. PMID:29292763

The Many Faces of Graphene as Protection Barrier. Performance under Microbial Corrosion and Ni Allergy Conditions

Directory of Open Access Journals (Sweden)

Carolina Parra

2017-12-01

Full Text Available In this work we present a study on the performance of CVD (chemical vapor deposition graphene coatings grown and transferred on Ni as protection barriers under two scenarios that lead to unwanted metal ion release, microbial corrosion and allergy test conditions. These phenomena have a strong impact in different fields considering nickel (or its alloys is one of the most widely used metals in industrial and consumer products. Microbial corrosion costs represent fractions of national gross product in different developed countries, whereas Ni allergy is one of the most prevalent allergic conditions in the western world, affecting around 10% of the population. We found that grown graphene coatings act as a protective membrane in biological environments that decreases microbial corrosion of Ni and reduces release of Ni2+ ions (source of Ni allergic contact hypersensitivity when in contact with sweat. This performance seems not to be connected to the strong orbital hybridization that Ni and graphene interface present, indicating electron transfer might not be playing a main role in the robust response of this nanostructured system. The observed protection from biological environment can be understood in terms of graphene impermeability to transfer Ni2+ ions, which is enhanced for few layers of graphene grown on Ni. We expect our work will provide a new route for application of graphene as a protection coating for metals in biological environments, where current strategies have shown short-term efficiency and have raised health concerns.

76 FR 34145 - Safety Zone, Barrier Testing Operations, Chicago Sanitary and Ship Canal, Romeoville, IL

Science.gov (United States)

2011-06-13

...-AA00 Safety Zone, Barrier Testing Operations, Chicago Sanitary and Ship Canal, Romeoville, IL AGENCY.... Construction on Barrier IIB has been completed. Operational and safety testing was conducted in February 2011... dispersal barrier IIA and IIB. This safety zone will be enforced daily from 7 a.m. to 11 a.m. and from 1 p.m...

An Analysis on the Moisture and Thermal Protective Performance of Firefighter Clothing Based on Different Layer Combinations and Effect of Washing on Heat Protection and Vapour Transfer Performance

Directory of Open Access Journals (Sweden)

Ozgur Atalay

2015-01-01

Full Text Available Fabric assemblies for firefighting clothing have been tested for heat protection and comfort. The constituent materials and fabric structures have been specifically selected and tailored for firefighters’ clothing. In order to do this, four types of outer shell fabrics, four types of moisture barrier fabrics, and four types of heat barriers with different weights and material compositions were used to make a multilayered fabric assembly. Heat transfer (flame, heat transfer (radiant, and water vapour resistance tests were conducted according to the latest EN469 test standard which also recommends washing tests. These tests reveal that material content and material brand have considerable effect on the required performance levels of heat protection. In addition, while washing tests have improved water vapor transfer properties, they have a deteriorating effect on heat protection performance. Considering heat protection and moisture comfort properties, the optimal assemblies are thereby identified.

An evaluation of risk methods for prioritizing fire protection features: a procedure for fire barrier penetration seals

International Nuclear Information System (INIS)

Dey, M.K.

2004-01-01

This paper generally evaluates risk methods available for prioritizing fire protection features. Risk methods involving both the use of qualitative insights, and quantitative results from a fire probabilistic risk analysis are reviewed. The applicability of these methods to develop a prioritized list of fire barrier penetration seals in a plant based on risk significance is presented as a procedure to illustrate the benefits of the methods. The paper concludes that current fire risk assessment methods can be confidently used to prioritize plant fire protection features, specifically fire barrier penetration seals. Simple prioritization schemes, using qualitative assessments and insights from fire PRA methodology may be implemented without the need for quantitative results. More elaborate prioritization schemes that allow further refinements to the categorization process may be implemented using the quantitative results of the screening processes in good fire PRAs. The use of the quantitative results from good fire PRAs provide several benefits for risk prioritization of fire protection features at plants, mainly from the plant systems analyses conducted for a fire PRA

Chemical gel barriers as low-cost alternative to containment and in situ cleanup of hazardous wastes to protect groundwater

International Nuclear Information System (INIS)

1997-01-01

Chemical gel barriers are being considered as a low-cost alternative for containment and in situ cleanup of hazardous wastes to protect groundwater. Most of the available gels in petroleum application are non-reactive and relative impermeable, providing a physical barriers for all fluids and contaminants. However, other potential systems can be envisioned. These systems could include gels that are chemically reactive and impermeable such that most phase are captured by the barriers but the contaminants could diffuse through the barriers. Another system that is chemically reactive and permeable could have potential applications in selectivity capturing contaminants while allowing water to pass through the barriers. This study focused on chemically reactive and permeable gel barriers. The gels used in experiment are DuPont LUDOX SM colloidal silica gel and Pfizer FLOPAAM 1330S hydrolyzed polyacrylamide (HPAM) gel

Evaluation of protection factor of respiratory protective equipment using indigenously developed protection factor test facility

International Nuclear Information System (INIS)

Patkulkar, D.S.; Ganesh, G.; Tripathi, R.M.

2018-01-01

Assigned protection factor (APF) is an indicator representing effectiveness of a respirator and it provides workplace level of respiratory protection for workers in providing protection against exposure to airborne contaminants Occupational Safety and Health Administration (OSHA) specifies 'Respirator APF' and 'Maximum Use Concentration' (MUC - a term derived using APF) shall be an integral part of Respirator Protection Standard. MUC establishes the maximum airborne concentration of a contaminant in which a respirator with a given APF may be used. The use of particulate respirators such as half face mask, full face mask and powered air purifying respirators is essential for radioactive jobs in nuclear facilities to prevent any intake of radionuclide. With this impetus, the Protection Factor Test Facility (PFTF) for testing and evaluation of respiratory protective equipment meeting relevant applicable standards was designed, fabricated and installed in Respiratory Protective Equipment Laboratory of Health Physics Division

Drywall plates evaluation as protection barriers in dental X-rays and mammography facilities

International Nuclear Information System (INIS)

Guevara R, V. Y.; Romero C, N.; Berrocal T, M.

2014-08-01

In the dental X-rays and mammography facilities, usually lead shielded walls as protective barriers are used. Lead is a good attenuator for X-rays, but has toxic properties and its cost is high. Mammography equipment s emit low-energy photons in the range of 25 keV to 35 keV, on current computers; the primary radiation beam is intercepted by the image receptor. Peri apical dental equipment s emit photons in the range of 50 to 90 keV, their filtration is fixed. These devices emit a collimated beam whose diameter is slightly larger than the diagonal dimension of a standard film of dental X-rays. When a dental x-ray is performed, the radiation beam is partially attenuated by the patient. Drywall is a material consisting of plasterboard between two cardboard layers, being its components gypsum and cellulose generally. It is used in construction for execution of interior walls, ceilings and wall coverings, could also serve as a replacement for lead as well as other materials. In this paper three drywall prototypes (Giplac), formed with 02, 04 and 06 drywall layers (13, 16 and 20 cm of thickness respectively) were tested as barriers against primary and secondary X-ray radiation that come from dental and mammography equipment s. The results show that the drywall prototype, 02 layers, efficiently attenuates the secondary radiation beam produced by conventional mammography equipment. And the prototype 04 and 06 layers, efficiently attenuates the primary radiation beam produced by peri apical dental equipment. (author)

Why testes are resistant to hydatidosis: Is blood-testis-barrier ...

African Journals Online (AJOL)

There was demonstrable hydatid cyst (protoscoleces and germinative layer) in testes of five rabbits from Group A, but in one rabbit, both testes were normal. In Group B, three out of four rabbits developed peritoneal hydatidosis. The mechanism of testicular resistance to echinococcosis could be due to blood-testis barrier ...

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants.

Science.gov (United States)

Simal-Gándara, J; Sarria-Vidal, M; Koorevaar, A; Rijk, R

2000-08-01

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick oriented PP) into the food stimulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.

Development of risk-oriented methods for evaluating the reliability of protective barriers security objects with highly radioactive sources

International Nuclear Information System (INIS)

Skalozubov, V.I.; Vashchenko, V.N.; Zlochevskij, V.V.

2012-01-01

The paper discusses an alternative approach is the definition of probabilistic safety indicators NPP, based on estimates of the probability of failure of protective safety barriers under the influence of fatigue mechanisms of degradation of

Conducting an inspection of protection program operations

International Nuclear Information System (INIS)

Brown, S.; Howell, J.

1987-01-01

Protection Program Operations (PPO) encompasses the entire physical security program at a facility, including security construction and equipment, procedures, forces, management and supervision, and the integration of these elements into a total system. PPO subtopics are Physical Security Systems (PSS), Protection Forces (PF), and System Performance Tests (SPT). PSS assesses those security elements designed to protect security interests, and include sensors, surveillance devices, systems for transmission and integration of alarm and assessment information, barriers, lighting, etc. PF assesses the management, training, equipment and facilities, and skills and knowledge of the protective force. SPT includes Force-on-Force, Emergency Management Performance Test, and Limited Scope Performance Tests

CMHC research project: Testing of air barrier construction details, II: Report

Energy Technology Data Exchange (ETDEWEB)

1993-01-01

Air leakage control through the building envelope of wood framed houses is more important than ever. The leakage of air is controlled by the air barrier system. There are several new technologies to construct an air barrier system for the building envelope. These are the Poly Approach, the Air Drywall Approach and the EASE system. The development of these systems was undertaken primarily by the building community without significant research and development. The purpose of this study was to determine the actual performance of several different types of construction details for each of the different approaches. Each of these details was designed and constructed using one of the air barrier methods and tested in the laboratory. The test details included the sill plate, the partition wall, the stair stringer, the electrical outlets, the bathtub detail, the plumbing stack detail, the metal chimney detail, the bathroom fan detail and the EASE wall system.

Scientific investigation plan for initial engineered barrier system field tests

International Nuclear Information System (INIS)

Wunan Lin.

1993-02-01

The purpose of this Scientific Investigation Plan (SIP) is to describe tests known as Initial Engineered Barrier System Field Tests (IEBSFT) and identified by Work Breakdown Structure as WBS 1.2.2.2.4. The IEBSFT are precursors to the Engineered Barrier System Field Test (EBSFT), WBS 1.2.2.2.4, to be conducted in the Exploratory Study Facility (ESF) at Yucca Mountain. The EBSFT and IEBSFT are designed to provide information on the interaction between waste packages (simulated by heated containers) and the surrounding rock mass, its vadose water, and infiltrated water. Heater assemblies will be installed in drifts or boreholes openings and heated to measure moisture movement during heat-up and subsequent cool-down of the rock mass. In some of the tests, infiltration of water into the heated rock mass will be studied. Throughout the heating and cooling cycle, instruments installed in the rock will monitor such parameters as temperature, moisture content, concentration of some chemical species, and stress and strain. Rock permeability measurements, rock and fluid (water and gas) sampling, and fracture pattern measurements will also be made before and after the test

1981 radon barrier field test at Grand Junction uranium mill tailings pile

International Nuclear Information System (INIS)

Hartley, J.N.; Gee, G.W.; Baker, E.G.; Freeman, H.D.

1983-04-01

Technologies to reduce radon released from uranium mill tailings are being investigated by Pacific Northwest Laboratory as part of the Department of Energy's Uranium Mill Tailings Remedial Action Project (UMTRAP) Technology development program. These technologies include: (1) earthen cover systems, (2) multilayer cover systems, and (3) asphalt emulsion radon barrier systems. During the summer of 1981, a field test was initiated at the Grand Junction, Colorado, uranium tailings pile to evaluate and compare the effectiveness of each radon barrier system. Test plots cover about 1.2 ha (3 acres). The field test has demonstrated the effectiveness of all three cover systems in reducing radon release to near background levels ( 2 s - 1 ). In conjunction with the field tests, column tests (1.8 m diameter) were initiated with cover systems similar to those in the larger field test plots. The column tests allow a direct comparison of the two test procedures and also provide detailed information on radon transport

Barriers and Facilitators to HIV Testing Among Zambian Female Sex Workers in Three Transit Hubs.

Science.gov (United States)

Chanda, Michael M; Perez-Brumer, Amaya G; Ortblad, Katrina F; Mwale, Magdalene; Chongo, Steven; Kamungoma, Nyambe; Kanchele, Catherine; Fullem, Andrew; Barresi, Leah; Bärnighausen, Till; Oldenburg, Catherine E

2017-07-01

Zambia has a generalized HIV epidemic, and HIV is concentrated along transit routes. Female sex workers (FSWs) are disproportionately affected by the epidemic. HIV testing is the crucial first step for engagement in HIV care and HIV prevention activities. However, to date little work has been done with FSWs in Zambia, and little is known about barriers and facilitators to HIV testing in this population. FSW peer educators were recruited through existing sex worker organizations for participation in a trial related to HIV testing among FSWs. We conducted five focus groups with FSW peer educators (N = 40) in three transit towns in Zambia (Livingstone, Chirundu, and Kapiri Mposhi) to elicit community norms related to HIV testing. Emerging themes demonstrated barriers and facilitators to HIV testing occurring at multiple levels, including individual, social network, and structural. Stigma and discrimination, including healthcare provider stigma, were a particularly salient barrier. Improving knowledge, social support, and acknowledgment of FSWs and women's role in society emerged as facilitators to testing. Interventions to improve HIV testing among FSWs in Zambia will need to address barriers and facilitators at multiple levels to be maximally effective.

Potential of Lactobacillus plantarum CCFM639 in Protecting against Aluminum Toxicity Mediated by Intestinal Barrier Function and Oxidative Stress.

Science.gov (United States)

Yu, Leilei; Zhai, Qixiao; Tian, Fengwei; Liu, Xiaoming; Wang, Gang; Zhao, Jianxin; Zhang, Hao; Narbad, Arjan; Chen, Wei

2016-12-02

Aluminum (Al) is a ubiquitous metal that can seriously harm the health of animals and humans. In our previous study, we demonstrated that Lactobacillus plantarum CCFM639 can decrease Al burden in the tissues of mice by inhibiting intestinal Al absorption. The main aim of the present research was to investigate whether the protection by the strain is also associated with enhancement of the intestinal barrier, alleviation of oxidative stress and modulation of the inflammatory response. In an in vitro cell model, two protection modes (intervention and therapy) were examined and the results indicated that L. plantarum CCFM639 alleviated Al-induced cytotoxicity. In a mouse model, L. plantarum CCFM639 treatment was found to significantly alleviate oxidative stress in the intestinal tract, regulate the function of the intestinal mucosal immune system, restore the integrity of tight junction proteins and maintain intestinal permeability. These results suggest that in addition to Al sequestration, L. plantarum CCFM639 can also inhibit Al absorption by protecting the intestinal barrier, alleviating Al-induced oxidative stress and inflammatory response. Therefore, L. plantarum CCFM639 has the potential to be a dietary supplement ingredient that provides protection against Al-induced gut injury.

Potential of Lactobacillus plantarum CCFM639 in Protecting against Aluminum Toxicity Mediated by Intestinal Barrier Function and Oxidative Stress

Directory of Open Access Journals (Sweden)

Leilei Yu

2016-12-01

Full Text Available Aluminum (Al is a ubiquitous metal that can seriously harm the health of animals and humans. In our previous study, we demonstrated that Lactobacillus plantarum CCFM639 can decrease Al burden in the tissues of mice by inhibiting intestinal Al absorption. The main aim of the present research was to investigate whether the protection by the strain is also associated with enhancement of the intestinal barrier, alleviation of oxidative stress and modulation of the inflammatory response. In an in vitro cell model, two protection modes (intervention and therapy were examined and the results indicated that L. plantarum CCFM639 alleviated Al-induced cytotoxicity. In a mouse model, L. plantarum CCFM639 treatment was found to significantly alleviate oxidative stress in the intestinal tract, regulate the function of the intestinal mucosal immune system, restore the integrity of tight junction proteins and maintain intestinal permeability. These results suggest that in addition to Al sequestration, L. plantarum CCFM639 can also inhibit Al absorption by protecting the intestinal barrier, alleviating Al-induced oxidative stress and inflammatory response. Therefore, L. plantarum CCFM639 has the potential to be a dietary supplement ingredient that provides protection against Al-induced gut injury.

Motivators and barriers for HIV testing among men who have sex with men in Sweden.

Science.gov (United States)

Persson, Kristina Ingemarsdotter; Berglund, Torsten; Bergström, Jakob; Eriksson, Lars E; Tikkanen, Ronny; Thorson, Anna; Forsberg, Birger C

2016-12-01

To explore motivators and barriers to HIV testing and to assess the factors associated with testing among men who have sex with men. Previous research has considered fear, worries and structural barriers as hindrances to HIV testing among men who have sex with men. However, few studies have included assessments of actual HIV testing when exploring barriers or motivators for such testing. The design of the study was a stratified cross-sectional online survey (n = 2373). Factor analysis was conducted to analyse the barriers and motivators for HIV testing. Logistic regression analysis was conducted to assess predictors for HIV testing. Many men who have sex with men test for HIV regularly, and specific reasons for testing were having unprotected sex or starting/ending a relationship. A lack of awareness and a perception of being at low risk for exposure were common reasons for never being tested. Fear and anxiety as well as barriers related to the use of test services remain important hindrances for testing. Predictors associated with having been tested within the past 12 months were: younger age (15-25 years old compared with 47+); knowledge on where to take an HIV test on short notice as well as having talked with a counsellor, having received condoms for free, or having had unprotected anal intercourse with casual partners within the last 12 months. Easily accessible test services offering testing and counselling on short notice should be available for all men who have sex with men. Outreach activities, distribution of free condoms and testing at venues where men who have sex with men meet are important prevention add-ons that can contribute to increased awareness about HIV and testing. Test services must ensure confidentiality and health care professionals who meet men who have sex with men for testing need competency with regards to men who have sex with men sexual health needs. © 2016 John Wiley & Sons Ltd.

Man as a protective barrier in nuclear power plants

International Nuclear Information System (INIS)

Fechner, J.B.

1980-01-01

Evaluation of nuclear power plant incidents frequently reveals man as a major element of risk. Yet, in a nuclear power plant man has the function of an important protective barrier, either by maintaining the plant, by detecting and limiting faults or incidents, or by taking proper measures in accidents. This is true despite, or perhaps because of, the high degree of plant automation. For this reason, it is indispensable that a high level of engineered plant safeguards be accompanied by a minimum of faults contributed by human action. This implies that the staff and their working conditions must meet the same stringent safety requirements as the nuclear power plant proper. Reactor manufacturers, nuclear power plant operators and the responsible authorities try to optimize this human contribution. The Federal Ministry of the Interior, through its Special Technical Guidelines and its continuation training measures, occupies an important position in this respect. Further measures and ordinances are being prepared by that Ministry. (orig.) [de

Test validation of environmental barrier coating (EBC) durability and damage tolerance modeling approach

Science.gov (United States)

Abdul-Aziz, Ali; Najafi, Ali; Abdi, Frank; Bhatt, Ramakrishna T.; Grady, Joseph E.

2014-03-01

Protection of Ceramic Matrix Composites (CMCs) is rather an important element for the engine manufacturers and aerospace companies to help improve the durability of their hot engine components. The CMC's are typically porous materials which permits some desirable infiltration that lead to strength enhancements. However, they experience various durability issues such as degradation due to coating oxidation. These concerns are being addressed by introducing a high temperature protective system, Environmental Barrier Coating (EBC) that can operate at temperature applications1, 3 In this paper, linear elastic progressive failure analyses are performed to evaluate conditions that would cause crack initiation in the EBC. The analysis is to determine the overall failure sequence under tensile loading conditions on different layers of material including the EBC and CMC in an attempt to develop a life/failure model. A 3D finite element model of a dogbone specimen is constructed for the analyses. Damage initiation, propagation and final failure is captured using a progressive failure model considering tensile loading conditions at room temperature. It is expected that this study will establish a process for using a computational approach, validated at a specimen level, to predict reliably in the future component level performance without resorting to extensive testing.

Secoisolariciresinol diglucoside is a blood-brain barrier protective and anti-inflammatory agent: implications for neuroinflammation.

Science.gov (United States)

Rom, Slava; Zuluaga-Ramirez, Viviana; Reichenbach, Nancy L; Erickson, Michelle A; Winfield, Malika; Gajghate, Sachin; Christofidou-Solomidou, Melpo; Jordan-Sciutto, Kelly L; Persidsky, Yuri

2018-01-27

Secoisolariciresinol diglucoside (SDG), the main lignan in flaxseed, is known for its beneficial effects in inflammation, oxidative stress, heart disease, tumor progression, atherosclerosis, and diabetes. SDG might be an attractive natural compound that protects against neuroinflammation. Yet, there are no comprehensive studies to date investigating the effects of SDG on brain endothelium using relevant in vivo and in vitro models. We evaluated the effects of orally administered SDG on neuroinflammatory responses using in vivo imaging of the brain microvasculature during systemic inflammation and aseptic encephalitis. In parallel, the anti-inflammatory actions of SDG on brain endothelium and monocytes were evaluated in vitro blood-brain barrier (BBB) model. Multiple group comparisons were performed by one-way analysis of variance with Dunnet's post hoc tests. We found that SDG diminished leukocyte adhesion to and migration across the BBB in vivo in the setting of aseptic encephalitis (intracerebral TNFα injection) and prevented enhanced BBB permeability during systemic inflammatory response (LPS injection). In vitro SDG pretreatment of primary human brain microvascular endothelial cells (BMVEC) or human monocytes diminished adhesion and migration of monocytes across brain endothelial monolayers in conditions mimicking CNS inflammatory responses. Consistent with our in vivo observations, SDG decreased expression of the adhesion molecule, VCAM1, induced by TNFα, or IL-1β in BMVEC. SDG diminished expression of the active form of VLA-4 integrin (promoting leukocyte adhesion and migration) and prevented the cytoskeleton changes in primary human monocytes activated by relevant inflammatory stimuli. This study indicates that SDG directly inhibits BBB interactions with inflammatory cells and reduces the inflammatory state of leukocytes. Though more work is needed to determine the mechanism by which SDG mediates these effects, the ability of SDG to exert a multi

Motives and barriers to safer sex and regular STI testing among MSM soon after HIV diagnosis.

Science.gov (United States)

Heijman, Titia; Zuure, Freke; Stolte, Ineke; Davidovich, Udi

2017-03-07

Understanding why some recently with HIV diagnosed men who have sex with men (MSM) choose for safer sex and regular STI testing, whereas others do not, is important for the development of interventions that aim to improve the sexual health of those newly infected. To gain insight into motives and barriers to condom use and regular STI testing among MSM soon after HIV diagnosis, 30 HIV-positive MSM participated in semi-structured qualitative interviews on sexual health behaviours in the first year after HIV diagnosis. Typical barriers to condom use soon after diagnosis were emotions such as anger, relief, and feelings of vulnerability. Additional barriers were related to pre-diagnosis patterns of sexual-social behaviour that were difficult to change, communication difficulties, and substance use. Barriers to STI testing revolved around perceptions of low STI risk, faulty beliefs, and burdensome testing procedures. The great diversity of motives and barriers to condom use and STI testing creates a challenge to accommodate newly infected men with information, motivation, and communication skills to match their personal needs. An adaptive, tailored intervention can be a promising tool of support.

Nevada Test Site Radiation Protection Program

Energy Technology Data Exchange (ETDEWEB)

Radiological Control Managers' Council, Nevada Test Site

2007-08-09

Title 10 Code of Federal Regulations (CFR) 835, 'Occupational Radiation Protection', establishes radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of U.S. Department of Energy (DOE) activities. 10 CFR 835.101(a) mandates that DOE activities be conducted in compliance with a documented Radiation Protection Program (RPP) as approved by DOE. This document promulgates the RPP for the Nevada Test Site (NTS), related (onsite or offsite) DOE National Nuclear Security Administration Nevada Site Office (NNSA/NSO) operations, and environmental restoration offsite projects.

A decision model to allocate protective safety barriers and mitigate domino effects

International Nuclear Information System (INIS)

Janssens, Jochen; Talarico, Luca; Reniers, Genserik; Sörensen, Kenneth

2015-01-01

In this paper, we present a model to support decision-makers about where to locate safety barriers and mitigate the consequences of an accident triggering domino effects. Based on the features of an industrial area that may be affected by domino accidents, and knowing the characteristics of the safety barriers that can be installed to stall the fire propagation between installations, the decision model can help practitioners in their decision-making. The model can be effectively used to decide how to allocate a limited budget in terms of safety barriers. The goal is to maximize the time-to-failure of a chemical installation ensuring a worst case scenario approach. The model is mathematically stated and a flexible and effective solution approach, based on metaheuristics, is developed and tested on an illustrative case study representing a tank storage area of a chemical company. We show that a myopic optimization approach, which does not take into account knock-on effects possibly triggered by an accident, can lead to a distribution of safety barriers that are not effective in mitigating the consequences of a domino accident. Moreover, the optimal allocation of safety barriers, when domino effects are considered, may depend on the so-called cardinality of the domino effects. - Highlights: • A model to allocate safety barriers and mitigate domino effects is proposed. • The goal is to maximize the escalation time of the worst case scenario. • The model provides useful recommendations for decision makers. • A fast metaheuristic approach is proposed to solve such a complex problem. • Numerical simulations on a realistic case study are shown

Efficacy of a Hand Regimen in Skin Barrier Protection in Individuals With Occupational Irritant Contact Dermatitis.

Science.gov (United States)

Jordan, Laura

2016-11-01

Occupational irritant contact dermatitis (OICD) is a dif cult and hard to manage condition. It occurs more frequently in certain occupations where contact with harsh chemicals, use of alcohol-based disinfectants, and frequent hand washing heightens the risk. Treatment for OICD includes patient education in addition to physical, topical, and systemic therapies. To review the pathogenesis and treatment options for OICD and evaluate the ef cacy of a selective skin-care regimen involv- ing a hand protectant cream alone as well as combined with a repair cream and speci c cleanser. A single-center open study was performed comprising 42 healthy male and female adult volunteers prone to occupational irritant contact dermatitis due to frequent wet work or contact with detergents. Between day 0 and day 7, subjects applied a hand protectant cream as needed on both hands (at least twice daily). On days 7 to 14, subjects applied a hand protectant cream and cleanser as needed on both hands (at least twice daily) as well as a repair cream each evening. A diary log was given to each volunteer for application control and for a subjective evaluation of daily tolerability. In these subjects prone to occupational irritant contact dermatitis, the hand protectant cream applied during the initial 7-day period was effective in restoring the damaged skin barrier and improving the stratum corneum hydration. A regimen that combined the hand protectant and repair creams with a speci c cleanser during a further 7-day period allowed contin- ued improvement of skin hydration and additional clinical bene ts while respecting the skin barrier function. The results of this study support the use of a 3-step approach for patients who are at risk of repeated exposure to external irritants. J Drugs Dermatol. 2016;15(suppl 11):s81-85..

Hanford Site Permanent Isolation Surface Barrier Development Program: Fiscal year 1992 and 1993 highlights

International Nuclear Information System (INIS)

Cadwell, L.L.; Link, S.O.; Gee, G.W.

1993-09-01

The Hanford Site Permanent Isolation Surface Barrier Development Program was jointly developed by the Pacific Northwest Laboratory and Westinghouse Hanford Company to design and test an earthen cover system that can be used to inhibit water infiltration; plant, animal, and human intrusion; and wind and water erosion. Kaiser Engineers Hanford Company provided engineering design support for the program. Work on barrier design has been under way at Hanford for nearly 10 years. The comprehensive development of a long-term barrier, formerly the Hanford Site Protective Barrier Development Program, was initiated in FY 1986, and a general field-tested design is expected to be completed by FY 1998. Highlights of efforts in FY 1992 and FY 1993 included the resumption of field testing, the completion of the prototype barrier design, and the convening of an external peer review panel, which met twice with the barrier development team. The review panel provided helpful guidance on current and future barrier development activities, while commending the program for its significant technical contributions to innovative barrier technology development

CRASH TEST AND EVALUATION OF RESTRAINED SAFETY-SHAPE CONCRETE BARRIERS ON CONCRETE BRIDGE DECK

Science.gov (United States)

2018-01-01

This research designed and tested a new portable concrete barrier that meets the performance of MASH TL-4 and can be used in temporary and permanent applications on bridge decks. Additionally, this new barrier system will minimize deflection, allowin...

Institutional and structural barriers to HIV testing: elements for a theoretical framework.

Science.gov (United States)

Meyerson, Beth; Barnes, Priscilla; Emetu, Roberta; Bailey, Marlon; Ohmit, Anita; Gillespie, Anthony

2014-01-01

Stigma is a barrier to HIV health seeking, but little is known about institutional and structural expressions of stigma in HIV testing. This study examines evidence of institutional and structural stigma in the HIV testing process. A qualitative, grounded theory study was conducted using secondary data from a 2011 HIV test site evaluation data in a Midwestern, moderate HIV incidence state. Expressions of structural and institutional stigma were found with over half of the testing sites and at three stages of the HIV testing visit. Examples of structural stigma included social geography, organization, and staff behavior at first encounter and reception, and staff behavior when experiencing the actual HIV test. Institutional stigma was socially expressed through staff behavior at entry/reception and when experiencing the HIV test. The emerging elements demonstrate the potential compounding of stigma experiences with deleterious effect. Study findings may inform future development of a theoretical framework. In practice, findings can guide organizations seeking to reduce HIV testing barriers, as they provide a window into how test seekers experience HIV test sites at first encounter, entry/reception, and at testing stages; and can identify how stigma might be intensified by structural and institutional expressions.

Ultraviolet A photosensitivity profile of dexchlorpheniramine maleate and promethazine-based creams: Anti-inflammatory, antihistaminic, and skin barrier protection properties.

Science.gov (United States)

Facchini, Gustavo; Eberlin, Samara; Clerici, Stefano Piatto; Alves Pinheiro, Ana Lucia Tabarini; Costa, Adilson

2017-12-01

Unwanted side effects such as dryness, hypersensitivity, and cutaneous photosensitivity are challenge for adherence and therapeutical success for patients using treatments for inflammatory and allergic skin response. In this study, we compared the effects of two dermatological formulations, which are used in inflammatory and/or allergic skin conditions: dexchlorpheniramine maleate (DCP; 10 mg/g) and promethazine (PTZ; 20 mg/g). We evaluated both formulations for phototoxicity potential, skin irritation, anti-inflammatory and antihistaminic abilities, and skin barrier repair in vitro and ex vivo using the standard OECD test guideline n° 432, the ECVAM protocol n° 78, and cultured skin explants from a healthy patient. Ultraviolet A was chosen as exogenous agent to induce allergic and inflammatory response. Both PTZ and DCP promoted increases in interleukin-1 (IL-1) synthesis in response to ultraviolet A (UVA) radiation compared to control. However, the increase observed with PTZ was significantly greater than the DCP, indicating that the latter has a lower irritant potential. DCP also demonstrated a protective effect on UVA-induced leukotriene B4 and nuclear factor kappa B (NF-κB) synthesis. Conversely, PTZ demonstrates more robust UVA antihistaminic activity. Likewise, PTZ promoted a significantly greater increase in the production of involucrin and keratin 14, both associated with protective skin barrier property. In conclusion, these data suggest possible diverging UVA response mechanisms of DCP and PTZ, which gives greater insight into the contrasting photosensitizing potential between DCP and PTZ observed in the patients. © 2017 Wiley Periodicals, Inc.

Expression of PKA inhibitor (PKI) gene abolishes cAMP-mediated protection to endothelial barrier dysfunction.

Science.gov (United States)

Lum, H; Jaffe, H A; Schulz, I T; Masood, A; RayChaudhury, A; Green, R D

1999-09-01

We investigated the hypothesis that cAMP-dependent protein kinase (PKA) protects against endothelial barrier dysfunction in response to proinflammatory mediators. An E1-, E3-, replication-deficient adenovirus (Ad) vector was constructed containing the complete sequence of PKA inhibitor (PKI) gene (AdPKI). Infection of human microvascular endothelial cells (HMEC) with AdPKI resulted in overexpression of PKI. Treatment with 0.5 microM thrombin increased transendothelial albumin clearance rate (0.012 +/- 0.003 and 0.035 +/- 0.005 microl/min for control and thrombin, respectively); the increase was prevented with forskolin + 3-isobutyl-1-methylxanthine (F + I) treatment. Overexpression of PKI resulted in abrogation of the F + I-induced inhibition of the permeability increase. However, with HMEC infected with ultraviolet-inactivated AdPKI, the F + I-induced inhibition was present. Also, F + I treatment of HMEC transfected with reporter plasmid containing the cAMP response element-directed transcription of the luciferase gene resulted in an almost threefold increase in luciferase activity. Overexpression of PKI inhibited this induction of luciferase activity. The results show that Ad-mediated overexpression of PKI in endothelial cells abrogated the cAMP-mediated protection against increased endothelial permeability, providing direct evidence that cAMP-dependent protein kinase promotes endothelial barrier function.

Barrier penetration database

International Nuclear Information System (INIS)

Fainberg, A.; Bieber, A.M. Jr.

1978-11-01

This document is intended to supply the NRC and nuclear power plant licensees with basic data on the times required to penetrate forcibly the types of barriers commonly found in nuclear plants. These times are necessary for design and evaluation of the physical protection system required under 10CFR73.55. Each barrier listed is described in detail. Minor variations in basic barrier construction that result in the same penetration time, are also described

Protective effects of angiopoietin-like 4 on the blood-brain barrier in acute ischemic stroke treated with thrombolysis in mice.

Science.gov (United States)

Zhang, Bin; Xu, Xiaofeng; Chu, Xiuli; Yu, Xiaoyang; Zhao, Yuwu

2017-04-03

Given the risk of blood-brain barrier damage (BBB) caused by ischemic and tissue plasminogen activator thrombolysis, the preservation of vascular integrity is important. Angiopoietin-like 4 (ANGPTL4), a protein secreted in hypoxia, is involved in the regulation of vascular permeability. We hypothesized that Angptl4 might exert a protective effect in thrombolysis through stabilizing blood-brain barrier and inhibit hyper-permeability. We investigated the role of Angptl4 in stroke using a transient focal cerebral ischemia mouse model. The treated mice were administered Angptl4 1h after the ischemic event upon reperfusion. Our results showed that Angptl4 combined with thrombolysis greatly reduced the infarct volume and consequent neurological deficit. Western blot analyses and gelatin zymography revealed that Angptl4 protected the integrity of the endothelium damaged by thrombolysis. Angptl4 inhibited the up-regulation of vascular endothelial growth factor (VEGF) in the vascular endothelium after stroke, which was suppressed by counteracting VEGFR signaling and diminishing downstream Src signaling, and led to the increased stability of junctions and improved endothelial cell barrier integrity. These findings demonstrated that Angptl4 protects the permeability of the BBB damaged by ischemic and thrombolysis. Suggested that Angptl4 might be a promising target molecule in therapies for vasoprotection after thrombolysis treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Proactive penicillin allergy testing in primary care patients labeled as allergic: outcomes and barriers.

Science.gov (United States)

Sundquist, Britta K; Bowen, Brady J; Otabor, Uwa; Celestin, Jocelyn; Sorum, Paul C

2017-11-01

To promote penicillin allergy testing in an outpatient setting in patients labeled as penicillin allergic, to determine the number of those who are truly allergic, evaluate patient satisfaction with the testing, and educate both patients and clinicians about testing. Patients with a history of penicillin allergy listed in their EHR were screened and recruited by their primary care office and referred for penicillin allergy testing. The results of allergy testing and patient satisfaction after testing were the main outcomes. We also surveyed the primary care physicians about perceived barriers to recruitment. A total of 82 patients were recruited, although only 37 actually underwent testing. None of these 37 had a positive skin test, and none of 36 had a positive oral challenge (1 refused it). Following testing, 2 patients (5%) had subjective reactions within 24 h. Thirty-one patients (84%) responded to a post-testing follow-up questionnaire; 3 (10%) were subsequently treated with a beta-lactam, and all reported that testing provided important information to their medical history. Providers identified time constraints, either their or their patients lack of time, as the major barrier to recruitment. Penicillin allergy testing safely evaluates patients labeled as penicillin allergic. It is well tolerated, and embraced by the patients who undergo testing. In our study, none of the patients tested had an allergic reaction, but we identified multiple barriers to developing a protocol for testing patients from the primary care setting.

Information barriers

International Nuclear Information System (INIS)

Fuller, J.L.; Wolford, J.

2001-01-01

Full text: An information barrier (IB) consists of procedures and technology that prevent the release of sensitive information during a joint inspection of a sensitive nuclear item, and provides confidence that the measurement system into which it has been integrated functions exactly as designed and constructed. Work in the U.S. on radiation detection system information barriers dates back at least to 1990, even though the terminology is more recent. In January 1999 the Joint DoD-DOE Information Barrier Working Group was formed in the United States to help coordinate technical efforts related to information barrier R and D. This paper presents an overview of the efforts of this group, by its Chairs, as well as recommendations for further information barrier R and D. Progress on the demonstration of monitoring systems containing IBs is also provided. From the U.S. perspective, the basic, top-level functional requirements for the information barrier portion of an integrated radiation signature-information barrier inspection system are twofold: The host must be assured that his classified information is protected from disclosure to the inspecting party; and The inspecting party must be confident that the integrated inspection system measures, processes, and presents the radiation-signature-based measurement conclusion in an accurate and reproducible manner. It is the position of the United States that in the absence of any agreement to share classified nuclear weapons design information in the conduct of an inspection regime, the requirement to protect host country classified warhead design information is paramount and admits no tradeoff versus the confidence provided to the inspecting party in the accuracy and reproducibility of the measurements. The U.S. has reached an internal consensus on several critical design elements that define a general standard for radiation signature information barrier design. These criteria have stood the test of time under intense

Adolescents and the right to health: eliminating age-related barriers to HIV/AIDS services in Rwanda.

Science.gov (United States)

Binagwaho, Agnes; Fuller, Arlan; Kerry, Vanessa; Dougherty, Sarah; Agbonyitor, Mawuena; Wagner, Claire; Nzayizera, Rodrigue; Farmer, Paul

2012-01-01

Under international, regional, and domestic law, adolescents are entitled to measures ensuring the highest attainable standard of health. For HIV/AIDS, this is essential as adolescents lack many social and economic protections and are disproportionately vulnerable to the effects of the disease. In many countries, legal protections do not always ensure access to health care for adolescents, including for HIV/AIDS prevention, treatment, and care. Using Rwanda as an example, this article identifies gaps, policy barriers, and inconsistencies in legal protection that can create age-related barriers to HIV/AIDS services and care. One of the most pressing challenges is defining an age of majority for access to prevention measures, such as condoms, testing and treatment, and social support. Occasionally drawing on examples of existing and proposed laws in other African countries, Rwanda and other countries may strengthen their commitment to adolescents' rights and eliminate barriers to prevention, family planning, testing and disclosure, treatment, and support. Among the improvements, Rwanda and other countries must align its age of consent with the actual behavior of adolescents and ensure privacy to adolescents regarding family planning, HIV testing, disclosure, care, and treatment.

An evaluation of the fire barrier system thermo-lag 330-1

International Nuclear Information System (INIS)

Nowlen, S.P.

1994-09-01

This report presents the results of three fire endurance tests and one ampacity derating test set of the fire barrier system Thermo-Lag 330-1 Subliming Coating. Each test was performed using cable tray specimens protected by a nominal three-hour fire barrier envelope comprised of two layers of nominal 1/2 inch thick material. The fire barrier systems for two of the three fire endurance test articles and for the ampacity derating test article were installed in accordance with the manufacturer's installations procedures. The barrier system for the third fire endurance test article was a full reproduction of one of the original manufacturer's qualification test articles. This final test article included certain installation enhancements not considered typical of current nuclear power plant installations. The primary criteria for fire endurance performance evaluation was based on cable circuit integrity testing. Secondary consideration was also given to the temperature rise limits set forth in the ASTM E119 standard fire barrier test procedure. All three of the fire endurance specimens failed prematurely. Circuit integrity failures for the two fire endurance test articles with procedures-based installations were recorded at approximately 76 and 59 minutes into the exposures for a 6 inch wide and 12 inch wide cable tray respectively. Temperature excursion failures (single point) for these two test articles were noted at approximately 65 and 56 minutes respectively. The first circuit integrity failure for the full reproduction test article was recorded approximately 119 minutes into the exposure, and the first temperature excursion failure for this test article was recorded approximately 110 minutes into the exposure

Fire Resistance Tests of Various Fire Protective Coatings

Directory of Open Access Journals (Sweden)

Mindaugas GRIGONIS

2011-03-01

Full Text Available Tests were carried out on more than 14 different samples of fire protective coatings in order to investigate a relation between the thickness of the intumescent fire protection coating and the time of exposure to heat. A number of coatings of different chemical composition enabled to determine the fire resistance behaviour patterns. During test the one-side and volumetric methods were employed in observance of the standard temperature-time curves. For one-side method, the coating was applied on one side and all edges of the specimen, whereas for volumetric test the specimens were completely covered with fire protective coating. It is shown that a layer of coating protects the specimen's surface from heat exposure for a certain period of time until full oxidation of the coating occurs. The efficiency of fire protective coatings also depends on thickness of the charred layer of the side exposed to heat.http://dx.doi.org/10.5755/j01.ms.17.1.257

Surface barrier research at the Hanford Site

International Nuclear Information System (INIS)

Gee, G.W.; Ward, A.L.; Fayer, M.J.

1997-01-01

At the DOE Hanford Site, a field-scale prototype surface barrier was constructed in 1994 over an existing waste site as a part of a CERCLA treatability test. The above-grade barrier consists of a fine-soil layer overlying coarse layers of sands, gravels, basalt rock (riprap), and a low permeability asphalt layer. Two sideslope configurations, clean-fill gravel on a 10:1 slope and basalt riprap on a 2:1 slope, were built and are being tested. Design considerations included: constructability; drainage and water balance monitoring, wind and water erosion control and monitoring; surface revegetation and biotic intrusion; subsidence and sideslope stability, and durability of the asphalt layer. The barrier is currently in the final year of a three-year test designed to answer specific questions related to stability and long-term performance. One half of the barrier is irrigated such that the total water applied, including precipitation, is 480 mm/yr (three times the long-term annual average). Each year for the past two years, an extreme precipitation event (71 mm in 8 hr) representing a 1,000-yr return storm was applied in late March, when soil water storage was at a maximum. While the protective sideslopes have drained significant amounts of water, the soil cover (2-m of silt-loam soil overlying coarse sand and rock) has never drained. During the past year there was no measurable surface runoff or wind erosion. This is attributed to extensive revegetation of the surface. In addition, the barrier elevation has shown a small increase of 2 to 3 cm that is attributed to a combination of root proliferation and freeze/thaw activity. Testing will continue through September 1997. Performance data from the prototype barrier will be used by DOE in site-closure decisions at Hanford

Antimicrobial Peptides, Infections and the Skin Barrier

DEFF Research Database (Denmark)

Clausen, Maja Lisa; Agner, Tove

2016-01-01

The skin serves as a strong barrier protecting us from invading pathogens and harmful organisms. An important part of this barrier comes from antimicrobial peptides (AMPs), which are small peptides expressed abundantly in the skin. AMPs are produced in the deeper layers of the epidermis and trans......The skin serves as a strong barrier protecting us from invading pathogens and harmful organisms. An important part of this barrier comes from antimicrobial peptides (AMPs), which are small peptides expressed abundantly in the skin. AMPs are produced in the deeper layers of the epidermis...

Mechanisms Underpinning Degradation of Protective Oxides and Thermal Barrier Coatings in High Hydrogen Content (HHC) - Fueled Turbines

Energy Technology Data Exchange (ETDEWEB)

Mumm, Daniel

2013-08-31

The overarching goal of this research program has been to evaluate the potential impacts of coal-derived syngas and high-hydrogen content fuels on the degradation of turbine hot-section components through attack of protective oxides and thermal barrier coatings. The primary focus of this research program has been to explore mechanisms underpinning the observed degradation processes, and connections to the combustion environments and characteristic non-combustible constituents. Based on the mechanistic understanding of how these emerging fuel streams affect materials degradation, the ultimate goal of the program is to advance the goals of the Advanced Turbine Program by developing materials design protocols leading to turbine hot-section components with improved resistance to service lifetime degradation under advanced fuels exposures. This research program has been focused on studying how: (1) differing combustion environments – relative to traditional natural gas fired systems – affect both the growth rate of thermally grown oxide (TGO) layers and the stability of these oxides and of protective thermal barrier coatings (TBCs); and (2) how low levels of fuel impurities and characteristic non-combustibles interact with surface oxides, for instance through the development of molten deposits that lead to hot corrosion of protective TBC coatings. The overall program has been comprised of six inter-related themes, each comprising a research thrust over the program period, including: (i) evaluating the role of syngas and high hydrogen content (HHC) combustion environments in modifying component surface temperatures, heat transfer to the TBC coatings, and thermal gradients within these coatings; (ii) understanding the instability of TBC coatings in the syngas and high hydrogen environment with regards to decomposition, phase changes and sintering; (iii) characterizing ash deposition, molten phase development and infiltration, and associated corrosive

Passive Barriers to Inadvertent Human Intrusion for Use at the Nevada Test Site

International Nuclear Information System (INIS)

NSTec Environmental Management

2007-01-01

In July1996, BN transmitted Passive Barriers to Inadvertent Human Intrusion for Use at the Nevada Test Site to the United States Department of Energy, under Contract DE-AC08-91NV10833. The 1996 paper had a limited distribution and was not reviewed for public release. In 2007, National Security Technologies LLC (NSTec) made minor revisions to conform to current editorial standards of the NNSA/NSO and to meet current security requirements for public release. The primary purpose of this study was to identify types of engineered passive barriers that could deter future intrusion into buried low-level radioactive waste, particularly intrusion by drilling water wells. The study considered drilling technology, many natural and man-made materials, and both underground and above-ground barriers. Based on cost and effectiveness, the report recommended underground barriers consisting of a layer of rubble or tires. An aboveground barrier mound might also prove effective, but would cost more, and may become an attractive nuisance (e.g., might, after their purpose has been forgotten, encourage exploration for the sake of satisfying curiosity). Advances in drilling technology could render any engineered barriers ineffective if there is motivation to penetrate the barriers

Still a hot issue. US fire protection 20 years on

International Nuclear Information System (INIS)

Hathaway, L.R.

1995-01-01

Current fire protection concerns in the US nuclear industry are reviewed. Twenty years ago, a fire at the Brown's Ferry nuclear plant triggered a vigorous programme of regulation by the US Nuclear Regulatory Commission (NRC) and a still active response by power plant operators in seeking protection measures to meet the NRC criteria. The largest fire protection issue facing the industry concerns Thermo-Lag, a product formed from resins, subliming materials and fibreglass. This fire resistant wrap was installed in about 75 plants to provide a barrier between safety related cable systems. The Brown's Ferry fire has re-emphasised the importance of the separation criteria between redundant safety systems. Since 1989, however, there have been doubts about the adequacy of Thermo-Lag barriers and a major testing and analysis project addressing the problem is currently being sponsored by six utilities. Other regulatory- related issues facing the industry are the recently proposed defence-in-depth fire protection methodology, and for the future, fire protection strategies to cover shutdown, turbine generators and penetration seals through fire barriers. (UK)

Ang-(1-7) exerts protective role in blood-brain barrier damage by the balance of TIMP-1/MMP-9.

Science.gov (United States)

Wu, Jitao; Zhao, Duo; Wu, Shuang; Wang, Dan

2015-02-05

Cerebrovascular disease (CVD) ranks as the top three health risks, specially cerebral ischemia characterized with the damage of blood-brain barrier (BBB). The angiotensin Ang-(1-7) was proven to have a protective effect on cerebrovascular diseases. However, its role on blood-brain barrier and the underlying molecular mechanism remains unclear. In this study, Ang-(1-7) significantly relieved damage of ischemia reperfusion injury on blood-brain barrier in cerebral ischemia reperfusion injury (IRI) rats. Furthermore, its treatment attenuated BBB permeability and brain edema. Similarly, Ang-(1-7) also decreased the barrier permeability of brain endothelial cell line RBE4. Further analysis showed that Ang-(1-7) could effectively restore tight junction protein (claudin-5 and zonula occludens ZO-1) expression levels both in IRI-rats and hypoxia-induced RBE4 cells. Furthermore, Ang-(1-7) stimulation down-regulated hypoxia-induced matrix metalloproteinase-9 (MMP-9) levels, whose silencing with (matrix metalloproteinase-9 hemopexin domain) MMP9-PEX inhibitor significantly increased the expression of claudin-5 and ZO-1. Further mechanism analysis demonstrated that Ang-(1-7) might junction protein levels by tissue inhibitor of metalloproteinase 1 (TIMP1)-MMP9 pathway, because Ang-(1-7) enhanced TIMP1 expression, whose silencing obviously attenuated the inhibitor effect of Ang-(1-7) on MMP-9 levels and decreased Ang-(1-7)-triggered increase in claudin-5 and ZO-1. Together, this study demonstrated a protective role of Ang-(1-7) in IRI-induced blood-brain barrier damage by TIMP1-MMP9-regulated tight junction protein expression. Accordingly, Ang-(1-7) may become a promising therapeutic agent against IRI and its complications. Copyright © 2014 Elsevier B.V. All rights reserved.

Barrier Performance of CVD Graphene Films Using a Facile P3HT Thin Film Optical Transmission Test

Directory of Open Access Journals (Sweden)

Srinivasa Kartik Nemani

2018-01-01

Full Text Available The barrier performance of CVD graphene films was determined using a poly(3-hexylthiophene (P3HT thin film optical transmission test. P3HT is a semiconducting polymer that photo-oxidatively degrades upon exposure to oxygen and light. The polymer is stable under ambient conditions and indoor lighting, enabling P3HT films to be deposited and encapsulated in air. P3HT’s stability under ambient conditions makes it desirable for an initial evaluation of barrier materials as a complimentary screening method in combination with conventional barrier tests. The P3HT test was used to demonstrate improved barrier performance for polymer substrates after addition of CVD graphene films. A layer-by-layer transfer method was utilized to enhance the barrier performance of monolayer graphene. Another set of absorption measurements were conducted to demonstrate the barrier performance of graphene and the degradation mechanism of graphene/P3HT over multiple wavelengths from 400 to 800 nm. The absorption spectra for graphene/polymer composite were simulated by solving Fresnel equations. The simulation results were found to be in good agreement with the measured absorption spectra. The P3HT degradation results qualitatively indicate the potential of graphene films as a possible candidate for medium performance barriers.

Permanent isolation surface barrier development plan

International Nuclear Information System (INIS)

Wing, N.R.

1994-01-01

The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no open-quotes provenclose quotes long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems

Permanent isolation surface barrier development plan

Energy Technology Data Exchange (ETDEWEB)

Wing, N.R.

1994-01-01

The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no {open_quotes}proven{close_quotes} long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems.

Combined pump and marking tests for determining protection zones

Energy Technology Data Exchange (ETDEWEB)

Hoetzl, H.; Brauns, J.

1982-02-01

Under difficult conditions the determination of the protection area II on the basis of Mear pump tests becomes uncertain. The report shows how in such cases the results of supplementary marking tests can establish a more accurate finding. The execution of combined pump and marking tests enables us to check data gained on a theoretical basis and possibly alter these. This method is described in an example, in which certain hydrogeological conditions and rival interests of ground water protection prevail on the one side and utilization of land on the other side. A general tendency exists to take the utmost protective measure in safeguarding ground water, however in cases of collision of interests the boundary of the protective area should be optimized. Supplementary marking tests can be of great significance.

Catalog of physical protection equipment. Book 1: Volume I. Barriers and structural components

International Nuclear Information System (INIS)

Haberman, W.

1977-06-01

A catalog of commercially available physical protection equipment has been prepared for use by the U.S. Nuclear Regulatory Commission (NRC). Included is information on barrier structures and equipment, interior and exterior intrusion detection sensors, entry (access) control devices, surveillance and alarm assessment equipment, contraband detection sensors, automated response equipment, general purpose displays and general purpose communications, with one volume devoted to each of these eight areas. For each item of equipment the information included consists of performance, physical, cost and supply/logistics data. The entire catalog is contained in three notebooks for ease in its use by licensing and inspection staff at NRC

Maximum dose angle for oblique incidence on primary beam protective barriers in the design of medical radiation therapy facilities

International Nuclear Information System (INIS)

Fondevila, Damian; Arbiser, Silvio; Sansogne, Rosana; Brunetto, Monica; Dosoretz, Bernardo

2008-01-01

Primary barrier determinations for the shielding of medical radiation therapy facilities are generally made assuming normal beam incidence on the barrier, since this is geometrically the most unfavorable condition for that shielding barrier whenever the occupation line is allowed to run along the barrier. However, when the occupation line (for example, the wall of an adjacent building) runs perpendicular to the barrier (especially roof barrier), then two opposing factors come in to play: increasing obliquity angle with respect to the barrier increases the attenuation, while the distance to the calculation point decreases, hence, increasing the dose. As a result, there exists an angle (α max ) for which the equivalent dose results in a maximum, constituting the most unfavorable geometric condition for that shielding barrier. Based on the usual NCRP Report No. 151 model, this article presents a simple formula for obtaining α max , which is a function of the thickness of the barrier (t E ) and the equilibrium tenth-value layer (TVL e ) of the shielding material for the nominal energy of the beam. It can be seen that α max increases for increasing TVL e (hence, beam energy) and decreases for increasing t E , with a range of variation that goes from 13 to 40 deg for concrete barriers thicknesses in the range of 50-300 cm and most commercially available teletherapy machines. This parameter has not been calculated in the existing literature for radiotherapy facilities design and has practical applications, as in calculating the required unoccupied roof shielding for the protection of a nearby building located in the plane of the primary beam rotation

Maximum dose angle for oblique incidence on primary beam protective barriers in the design of medical radiation therapy facilities.

Science.gov (United States)

Fondevila, Damián; Arbiser, Silvio; Sansogne, Rosana; Brunetto, Mónica; Dosoretz, Bernardo

2008-05-01

Primary barrier determinations for the shielding of medical radiation therapy facilities are generally made assuming normal beam incidence on the barrier, since this is geometrically the most unfavorable condition for that shielding barrier whenever the occupation line is allowed to run along the barrier. However, when the occupation line (for example, the wall of an adjacent building) runs perpendicular to the barrier (especially roof barrier), then two opposing factors come in to play: increasing obliquity angle with respect to the barrier increases the attenuation, while the distance to the calculation point decreases, hence, increasing the dose. As a result, there exists an angle (alpha(max)) for which the equivalent dose results in a maximum, constituting the most unfavorable geometric condition for that shielding barrier. Based on the usual NCRP Report No. 151 model, this article presents a simple formula for obtaining alpha(max), which is a function of the thickness of the barrier (t(E)) and the equilibrium tenth-value layer (TVL(e)) of the shielding material for the nominal energy of the beam. It can be seen that alpha(max) increases for increasing TVL(e) (hence, beam energy) and decreases for increasing t(E), with a range of variation that goes from 13 to 40 deg for concrete barriers thicknesses in the range of 50-300 cm and most commercially available teletherapy machines. This parameter has not been calculated in the existing literature for radiotherapy facilities design and has practical applications, as in calculating the required unoccupied roof shielding for the protection of a nearby building located in the plane of the primary beam rotation.

To Test or Not to Test: Barriers and Solutions to Testing African American College Students for HIV at a Historically Black College/University.

Science.gov (United States)

Hall, Naomi M; Peterson, Jennifer; Johnson, Malynnda

2014-01-01

Young African Americans are disproportionately affected by sexually transmitted infections, including HIV. The purpose was to identify reasons that African American college students at a historically Black college/university (HBCU) identified as barriers to HIV testing, and how these barriers can be removed. Fifty-seven heterosexual-identified undergraduate students (ages 18-25) attending an HBCU in the southeastern US participated in a mixed method study. Latent content analytic techniques were used to code the transcripts for themes and categories, and representative quotations were used in the findings. Quantitative data indicates high levels of perceived knowledge about HIV transmission, low perception of risk and concern of contracting HIV, yet continued sexual risk behavior. Qualitative data indicates three main themes used to avoid testing and three themes to encourage testing. Students were forthcoming in discussing the themes around avoidance of HIV testing (being scared to know, preferring not to know, and lack of discussion about HIV) and encouraging testing (group testing, increasing basic knowledge, and showing the reality of HIV). It is important for college healthcare professionals, researchers, and officials to identify appropriate ways to encourage HIV testing, and promote testing as part of overall health.

Field tests with vertical perforated drain pipes used for beach protection at Southern Holmsland Barrier on the Danish North Sea Coast

DEFF Research Database (Denmark)

Burcharth, Hans F.; Fredsøe, Jørgen

In accordance with the agreement of 18 August 2004 between Skagen Innovation Center (SIC) and the Danish Governmental Coastal Authority (KDI) a field test with the purpose of demonstrating the efficiency of the SIC vertical drain method as a mean for coastal protecting was initiated in a meeting 24...

CHARACTERIZATION OF BENTONITE FOR ENGINEERED BARRIER SYSTEMS IN RADIOACTIVE WASTE DISPOSAL SITES

Directory of Open Access Journals (Sweden)

Dubravko Domitrović

2012-07-01

Full Text Available Engineered barrier systems are used in radioactive waste disposal sites in order to provide better protection of humans and the environment from the potential hazards associated with the radioactive waste disposal. The engineered barrier systems usually contain cement or clay (bentonite because of their isolation properties and long term performance. Quality control tests of clays are the same for all engineering barrier systems. Differences may arise in the required criteria to be met due for different application. Prescribed clay properties depend also on the type of host rocks. This article presents radioactive waste management based on best international practice. Standard quality control procedures for bentonite used as a sealing barrier in radioactive waste disposal sites are described as some personal experiences and results of the index tests (free swelling index, water adsorption capacity, plasticity limits and hydraulic permeability of bentonite (the paper is published in Croatian.

Active barrier films of PET for solar cell application: Processing and characterization

International Nuclear Information System (INIS)

Rossi, Gabriella; Scarfato, Paola; Incarnato, Loredana

2014-01-01

A preliminary investigation was carried out on the possibility to improve the protective action offered by the standard multilayer structures used to encapsulate photovoltaic devices. With this aim, a commercial active barrier PET-based material, able to absorb oxygen when activated by liquid water, was used to produce flexible and transparent active barrier films, by means of a lab-scale film production plant. The obtained film, tested in terms of thermal, optical and oxygen absorption properties, shows a slow oxygen absorption kinetics, an acceptable transparency and an easy roll-to-roll processability, so proving itself as a good candidate for the development of protective coating for solar cells against the atmospheric degradation agents like the rain

Protection of blood retinal barrier and systemic vasculature by insulin-like growth factor binding protein-3.

Directory of Open Access Journals (Sweden)

Yagna P R Jarajapu

Full Text Available Previously, we showed that insulin growth factor (IGF-1 binding protein-3 (IGFBP-3, independent of IGF-1, reduces pathological angiogenesis in a mouse model of the oxygen-induced retinopathy (OIR. The current study evaluates novel endothelium-dependent functions of IGFBP-3 including blood retinal barrier (BRB integrity and vasorelaxation. To evaluate vascular barrier function, either plasmid expressing IGFBP-3 under the regulation of an endothelial-specific promoter or a control plasmid was injected into the vitreous humor of mouse pups (P1 and compared to the non-injected eyes of the same pups undergoing standard OIR protocol. Prior to sacrifice, the mice were given an injection of horseradish peroxidase (HRP. IGFBP-3 plasmid-injected eyes displayed near-normal vessel morphology and enhanced vascular barrier function. Further, in vitro IGFBP-3 protects retinal endothelial cells from VEGF-induced loss of junctional integrity by antagonizing the dissociation of the junctional complexes. To assess the vasodilatory effects of IGFBP-3, rat posterior cerebral arteries were examined in vitro. Intraluminal IGFBP-3 decreased both pressure- and serotonin-induced constrictions by stimulating nitric oxide (NO release that were blocked by L-NAME or scavenger receptor-B1 neutralizing antibody (SRB1-Ab. Both wild-type and IGF-1-nonbinding mutant IGFBP-3 (IGFBP-3NB stimulated eNOS activity/NO release to a similar extent in human microvascular endothelial cells (HMVECs. NO release was neither associated with an increase in intracellular calcium nor decreased by Ca(2+/calmodulin-dependent protein kinase II (CamKII blockade; however, dephosphorylation of eNOS-Thr(495 was observed. Phosphatidylinositol 3-kinase (PI3K activity and Akt-Ser(473 phosphorylation were both increased by IGFBP-3 and selectively blocked by the SRB1-Ab or PI3K blocker LY294002. In conclusion, IGFBP-3 mediates protective effects on BRB integrity and mediates robust NO release to stimulate

SU-E-T-243: Design of a Novel Testing Port for Radiation Protection and Shielding Measurements

International Nuclear Information System (INIS)

Tanny, S; Parsai, E; Harrell, D; Noller, J; Chopra, M

2015-01-01

Purpose: The majority of radiation shielding research utilizes Monte Carlo simulation because of the difficulty in eliminating secondary radiations from measurements. We have designed a test port into a primary barrier of our newest vault to allow for shielding measurements while ensuring adequate protection to the public and staff during normal machine operation. This port allows for measurement of attenuation values of shielding materials, differential dose albedos, and radiation scatter fractions. Methods: The vault design utilized the maze as part of a compound primary barrier. The test port is contained within the maze and is centered along isocenter. The inner 30 cm has a 20×20 cm 2 opening, while the remaining length has a 30×30 cm 2 opening. The block that contains the port has a density of 200 pcf to minimize internal scatter. The 30×30 cm 2 opening is occupied by removable 215 pcf concrete blocks. The innermost and outermost blocks activate an interlock wired into the beam-enable loop. This disallows beam-on in treatment mode if the interlock isn’t closed. The interlock can be overridden in service mode, or by-passed via an override switch in case of circuit failure. Results: The test port was installed in August. The beam is disabled when the interlock is tripped. Measurements taken when the primary beam is not incident on the port are indistinguishable from background. Ambient dose levels surrounding the vault with the designed shielding blocks in place are all within allowable limits for occupational workers. Conclusions: We have designed and installed a unique testing port for radiation protection and shielding measurements. This port is appropriately interlocked and designed to mitigate any risks of incidental exposure to staff or members of the public. The test port design allows measurements with “good geometry” and efficient removal of contaminating sources of radiation present in many shielding measurements. Daniel Harrell and Jim Noller

Overview of hydrothermal testing of waste-package barrier materials at the Basalt Waste Isolation Project

International Nuclear Information System (INIS)

1982-01-01

The current Waste Package Department (WPD) hydrothermal testing program for the Basalt Waste Isolation Project (BWIP) has followed a systematic approach for the testing of waste-barrier-basalt interactions based on sequential penetration of barriers by intruding groundwaters. Present test activities in the WPD program have focused on determining radionuclide solubility limits (or steady-state conditions) of simulated waste forms and the long-term stability of waste package barriers under site-specific hydrothermal conditions. The resulting data on solution compositions and solid alteration products have been used to evaluate waste form degradation under conditions specific to a nuclear waste repository located in basalt (NWRB). Isothermal, time-invariant compositional data on sampled solutions have been coupled with realistic hydrologic flow data for near-field and far-field modeling for the calculation of meaningful radionuclide release rates. Radionuclides that are not strongly sorbed or precipitated from solution and that, therefore, may require special attention to ensure their isolation within the waste package have been identified. Taken together, these hydrothermal test data have been used to establish design requirements for waste packages located in basalt

Hataedock treatment has preventive therapeutic effects for atopic dermatitis through skin barrier protection in Dermatophagoides farinae-induced NC/Nga mice.

Science.gov (United States)

Cha, Ho-Yeol; Ahn, Sang-Hyun; Cheon, Jin-Hong; Park, Sun-Young; Kim, Kibong

2017-07-12

Hataedock treatment is traditionally used for the purpose of preventing the future skin disease by feeding herbal extracts to the newborn in traditional Chinese and Korean medicine. This study investigated the preventive therapeutic effects of Hataedock (HTD) treatment for atopic dermatitis (AD) through skin barrier protection in Dermatophagoides farinae-induced NC/Nga mice. To the HTD treatment group, the extract of Coptis japonica Makino and Glycyrrhiza uralensis Fischer, which analyzed with High Performance Liquid Chromatography (HPLC)-fingerprint for quality consistency, was administered orally to the 3-week-old mice before inducing AD. After that, Dermatophagoides farinae was applied except the control group to induce AD-like skin lesions. We confirmed the effects of HTD on morphological changes, protection of skin barrier, regulation of Th2 differentiation, inflammation regulation and induction of apoptosis through histochemistry, immunohistochemistry, and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. HTD effectively reduced edema, angiogenesis and skin lesion. HTD also increased the levels of liver X receptor (LXR) and filaggrin but decreased the level of protein kinase C (PKC) (pprotection of skin barrier. Therefore, HTD may have potential applications for alternative and preventive treatment in the management of AD. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Alpha-Melanocyte Stimulating Hormone Protects against Cytokine-Induced Barrier Damage in Caco-2 Intestinal Epithelial Monolayers.

Directory of Open Access Journals (Sweden)

Judit Váradi

Full Text Available Alpha-melanocyte-stimulating hormone (α-MSH is a potent anti-inflammatory peptide with cytoprotective effect in various tissues. The present investigation demonstrates the ability of α-MSH to interact with intestinal epithelial cell monolayers and mitigate inflammatory processes of the epithelial barrier. The protective effect of α-MSH was studied on Caco-2 human intestinal epithelial monolayers, which were disrupted by exposure to tumor necrosis factor-α and interleukin-1β. The barrier integrity was assessed by measuring transepithelial electric resistance (TEER and permeability for marker molecules. Caco-2 monolayers were evaluated by immunohistochemistry for expression of melanocortin-1 receptor and tight junction proteins ZO-1 and claudin-4. The activation of nuclear factor kappa beta (NF-κB was detected by fluorescence microscopy and inflammatory cytokine expression was assessed by flow cytometric bead array cytokine assay. Exposure of Caco-2 monolayers to proinflammatory cytokines lowered TEER and increased permeability for fluorescein and albumin, which was accompanied by changes in ZO-1 and claudin-4 immunostaining. α-MSH was able to prevent inflammation-associated decrease of TEER in a dose-dependent manner and reduce the increased permeability for paracellular marker fluorescein. Further immunohistochemistry analysis revealed proinflammatory cytokine induced translocation of the NF-κB p65 subunit into Caco-2 cell nuclei, which was inhibited by α-MSH. As a result the IL-6 and IL-8 production of Caco-2 monolayers were also decreased with different patterns by the addition of α-MSH to the culture medium. In conclusion, Caco-2 cells showed a positive immunostaining for melanocortin-1 receptor and α-MSH protected Caco-2 cells against inflammatory barrier dysfunction and inflammatory activation induced by tumor necrosis factor-α and interleukin-1β cytokines.

Sandia Laboratories plutonium protection system

International Nuclear Information System (INIS)

Bernard, E.A.; Miyoshi, D.S.; Gutierrez, F.D.

1977-01-01

Sandia Laboratories is developing an improved plutonium protection system (PPS) to demonstrate new concepts for enhancing special nuclear materials safeguards. PPS concepts include separation of functions, real-time item accountability and improved means for control of materials, activities and personnel access. Physical barriers and a secure communications network are designed into the system to offer greater protection against sabotage, diversion and theft attempts. Prototype systems are being constructed at Hanford, Washington and Albuquerque, New Mexico and will be subjected to a comprehensive testing and evaluation program

The effects of revised barrier and dummy specification in the side impact test procedure or EuroNCAP

Energy Technology Data Exchange (ETDEWEB)

Waagmeester, C.D.; Versmissen, T.; Ratingen, M.R. van; Zuljar, R. [TNO Automotive, Crash Safety Center, Delft (Netherlands)

2001-07-01

In this paper the effects of potential changes to the side impact test in EuroNCAP are studied. Research in Europe has come to the point that enhanced alternatives will soon become available for the test tools used, in the form of the EUROSID-2 (ES-2), Q child dummies and the progressive MDB barrier. The objective of this study is to illustrate the effect that introduction of the new test tools could have in terms of injury outcome and rating for a typical mid-size family saloon vehicle. For this, a full-scale test, previously carried out as part of the EuroNCAP programme, has been repeated three times replacing the current barrier and/or dummies by the new alternatives. Even though these new tools are designed to meet the existing specifications, the comparison of old and new results show that the end result, i.e. the car rating, may be substantially influenced. For the car tested in this study, the added effect of dummy and barrier change would lower the rating from 14.56 to 11.62 points (91% to 73%). Some small, not critical, values measured with EUROSID-1 (V*C's) increased 500 to 600% by using the new tools. However, the car used in this study would still meet the ECE R95 criteria. Cars that are designed closer to the legislation limits may fail to comply. Comparing the 'New dummies - Old barrier' test with equivalent tests performed in the ES-2 evaluation program show a substantial variation in injury parameter results. Based on the four tests with one car type in this study it can be illustrated that the new barrier may show an undesired increase of crash test results. (orig.)

The impact of communication barriers on diagnostic confidence and ancillary testing in the emergency department.

Science.gov (United States)

Garra, Gregory; Albino, Hiram; Chapman, Heather; Singer, Adam J; Thode, Henry C

2010-06-01

Communication barriers (CBs) compromise the diagnostic power of the medical interview and may result in increased reliance on diagnostic tests or incorrect test ordering. The prevalence and degree to which these barriers affect diagnosis, testing, and treatment are unknown. To quantify and characterize CBs encountered in the Emergency Department (ED), and assess the effect of CBs on initial diagnosis and perceived reliance on ancillary testing. This was a prospective survey completed by emergency physicians after initial adult patient encounters. CB severity, diagnostic confidence, and reliance on ancillary testing were quantified on a 100-mm Visual Analog Scale (VAS) from least (0) to most (100). Data were collected on 417 ED patient encounters. CBs were reported in 46%; with a mean severity of 50 mm on a 100-mm VAS with endpoints of "perfect communication and "no communication." Language was the most commonly reported form of CB (28%). More than one CB was identified in 6%. The 100-mm VAS rating of diagnostic confidence was lower in patients with perceived CBs (64 mm) vs. those without CBs (80 mm), p Communication barriers in our ED setting were common, and resulted in lower diagnostic confidence and increased perception that ancillary tests are needed to narrow the diagnosis. Copyright 2010 Elsevier Inc. All rights reserved.

Accelerated Test Method for Corrosion Protective Coatings Project

Science.gov (United States)

Falker, John; Zeitlin, Nancy; Calle, Luz

2015-01-01

This project seeks to develop a new accelerated corrosion test method that predicts the long-term corrosion protection performance of spaceport structure coatings as accurately and reliably as current long-term atmospheric exposure tests. This new accelerated test method will shorten the time needed to evaluate the corrosion protection performance of coatings for NASA's critical ground support structures. Lifetime prediction for spaceport structure coatings has a 5-year qualification cycle using atmospheric exposure. Current accelerated corrosion tests often provide false positives and negatives for coating performance, do not correlate to atmospheric corrosion exposure results, and do not correlate with atmospheric exposure timescales for lifetime prediction.

Crash tests for passenger cars and their relationship to the actual accident occurrence

International Nuclear Information System (INIS)

Appel, Hermann; Lutter, Gerhard; Sigmund, Thomas

1994-01-01

Current consensus about crash tests implies that, for verification of self-protection of a vehicle or its occupants, at least three full size tests with the following specifications are necessary:(1)frontal impact against a rigid, non-moving 0 -barrier with 100% overlap;(2)frontal offset impact against a rigid, non-moving 15 -barrier with 50% overlap (impact speed between 50 and 55kmh -1 );(3)side impact of a moving deformable barrier; preferably according to EEVC-method (impact speed 50kmh -1 ).From the social general view it is not sufficient to test only the self-protection of the vehicle and to give most importance to the front of the vehicle. The other factors of passive safety, partner protection and compatibility, respectively, have to be included, as two thirds of the cost of injuries originates from car-to-car accidents, and only one third from vehicle collisions against fixed objects. It follows that at least one additional test of compatibility has to be added to those mentioned above. It has to be investigated whether this compatibility test could be a frontal impact against a controllably deformable barrier and could substitute one or even two of the first-mentioned tests. ((orig.))

'When I get better I will do the test': Facilitators and barriers to HIV ...

African Journals Online (AJOL)

'When I get better I will do the test': Facilitators and barriers to HIV testing in Northwest Region of Cameroon with implications for TB and HIV/AIDS control ... However, as a result of conflicting emotional experiences regarding to test or not to test, the decision-making process was not straightforward and this complex process ...

Operational test report - Project W-320 cathodic protection systems

International Nuclear Information System (INIS)

Bowman, T.J.

1998-01-01

Washington Administrative Code (WAC) 173-303-640 specifies that corrosion protection must be designed into tank systems that treat or store dangerous wastes. Project W-320, Waste Retrieval Sluicing System (WRSS), utilizes underground encased waste transfer piping between tanks 241-C-106 and 241-AY-102. Corrosion protection is afforded to the encasements of the WRSS waste transfer piping through the application of earthen ionic currents onto the surface of the piping encasements. Cathodic protection is used in conjunction with the protective coatings that are applied upon the WRSS encasement piping. WRSS installed two new two rectifier systems (46 and 47) and modified one rectifier system (31). WAC 173-303-640 specifies that the proper operation of cathodic protection systems must be confirmed within six months after initial installation. The WRSS cathodic protection systems were energized to begin continuous operation on 5/5/98. Sixteen days after the initial steady-state start-up of the WRSS rectifier systems, the operational testing was accomplished with procedure OTP-320-006 Rev/Mod A-0. This operational test report documents the OTP-320-006 results and documents the results of configuration testing of integrated piping and rectifier systems associated with the W-320 cathodic protection systems

Testing Digital Electronic Protection Systems

CERN Document Server

Gabourin, S

2011-01-01

This paper outlines the core concepts and realisation of the Safe Machine Parameters Controller (SMPC) testbench, based on a VME crate and LabVIEW program. Its main goal is to ensure the correct function of the SMPC for the protection of the CERN accelerator complex. To achieve this, the tester has been built to replicate the machine environment and operation, in order to ensure that the chassis under test is completely exercised. The complexity of the task increases with the number of input combinations. This paper also outlines the benefits and weaknesses of developing a test suite independently of the hardware being tested, using the “V” approach.

Protective effect of lactobacillus acidophilus and isomaltooligosaccharide on intestinal mucosal barriers in rat models of antibiotic-associated diarrhea

International Nuclear Information System (INIS)

Du Dan; Fang Lichao; Chen Bingbo; Wei Hong

2008-01-01

Objective: To investigate the protective effect of synbiotics combined lactobacillus acidophilus and iso-malto-oligosaccharide (IMO) on intestinal mucosal barriers in rat models of antibiotic-associated diarrhea(AAD). Methods: Rat models of AAD were prepared with lincomycin gavage for 5 days. The synbiotics was orally administered to the AAD rats daily at three different strengths for 7 days. The intestinal flora and intestinal mucus SIgA levels were determined on d6, d9 and d13. The histopathological changes of ileal mucosa were studied on d13. Results: In the prepared AAD model rats (on d6) there were lower intestinal mucus SIgA levels and intestinal flora disorders were demonstrated. The intestinal floras of the rats administering synbiotics were readjusted to the similar pattern of healthy rats with bacterial translocation corrected on d13 and the levels of SIgA were not significantly different from of the control (P>0.05). The histopathological picture was basically normal in the treated models on d13. Conclusion: The synbiotics combined lactobacillus acidophilus and isomaltooligosaccharide possessed good protective effect on the intestinal mucosal barrier in lincomycin induced rat models of AAD. (authors)

He-Ne laser protection barrier by means of poly (Tetrafluoroethylene-Perfluoro vinyl Ether) grafted by acrylic acid complexed with Cu(II)

International Nuclear Information System (INIS)

El-Ahdal, M.A.; Fayek, S.A.; El-Sawy, N.M.

2006-01-01

Appropriate eye and skin protection is a prerequisite for the safe operation of He-Ne laser in industrial and laboratory environments. In the present paper, measurement of the optical parameters of poly (tetrafluoroethylene-perfluorovinyl ether) grafted by acrylic acid and complexed with Cu(II) are reported. He-Ne laser beam radiation on wavelength of 632.8 nm and power 12.5mW was used. Transmittance and reflectance spectra and refractive index dispersion are presented. The study showed that the material has a protective level 4. Environmental conditions like thermal and fading processes were tested. This suggested that the material preserves its protective features as a protective eye and skin barriers of protective level 4. This was applied for occupational working time up to 8 h, temperature up to 50 degree C and for a time equal 74 days after laser irradiation. Radiation protection from laser sources has attracted a great deal of attention for long time because of their importance for human body. Intensive progress in lasers, optical communications, and data storage has challenged scientists to achieve perfection in optical components. These challenges have resulted in an active development of a wide variety of unconventional optical elements (Hariharan, 1996 and Efimov et al., 2002). Alexandrite solid state lasers with a wavelength of about 755 nm are frequently used in the field of medicine (Schirmarcher and Sutter, 2001). For removing tattoos, the Q-switched versions with impulse widths of several ten nanoseconds are an ideal instrument to keep the thermal stress of the patient's skin at low level. He-Ne laser is one of the most commonly used visible light lasers

A Novel Wound Retractor Combining Continuous Irrigation and Barrier Protection Reduces Incisional Contamination in Colorectal Surgery.

Science.gov (United States)

Papaconstantinou, Harry T; Ricciardi, Rocco; Margolin, David A; Bergamaschi, Roberto; Moesinger, Robert C; Lichliter, Warren E; Birnbaum, Elisa H

2018-03-09

Surgical site infection (SSI) remains a persistent and morbid problem in colorectal surgery. Key to its pathogenesis is the degree of intraoperative bacterial contamination at the surgical site. The purpose of this study was to evaluate a novel wound retractor at reducing bacterial contamination. A prospective multicenter pilot study utilizing a novel wound retractor combining continuous irrigation and barrier protection was conducted in patients undergoing elective colorectal resections. Culture swabs were collected from the incision edge prior to device placement and from the exposed and protected incision edge prior to device removal. The primary and secondary endpoints were the rate of enteric and overall bacterial contamination on the exposed incision edge as compared to the protected incision edge, respectively. The safety endpoint was the absence of serious device-related adverse events. A total of 86 patients were eligible for analysis. The novel wound retractor was associated with a 66% reduction in overall bacterial contamination at the protected incision edge compared to the exposed incision edge (11.9 vs. 34.5%, P contamination (9.5% vs. 33.3%, P contamination. Improved methods to counteract wound contamination represent a promising strategy for SSI prevention (NCT 02413879).

Richards Barrier LA Reference Design Feature Evaluation

International Nuclear Information System (INIS)

N.E. Kramer

1999-01-01

The Richards Barrier is one of the design features of the repository to be considered for the License Application (LA), Richards was a soil scientist who first described the diversion of moisture between two materials with different hydrologic properties. In this report, a Richards Barrier is a special type of backfill with a fine-grained material (such as sand) overlaying a coarse-grained material (such as gravel). Water that enters an emplacement drift will first encounter the fine-grained material and be transported around the coarse-grained material covering the waste package, thus protecting the waste package from contact with most of the groundwater. The objective of this report is to discuss the benefits and liabilities to the repository by the inclusion of a Richards Barrier type backfill in emplacement drifts. The Richards Barrier can act as a barrier to water flow, can reduce the waste package material dissolution rate, limit mobilization of the radionuclides, and can provide structural protection for the waste package. The scope of this report is to: (1) Analyze the behavior of barrier materials following the intrusion of groundwater for influxes of 1 to 300 mm per year. The report will demonstrate diversion of groundwater intrusions into the barrier over an extended time period when seismic activity and consolidation may cause the potential for liquefaction and settlement of the Richards Barrier. (2) Review the thermal effects of the Richards Barrier on material behavior. (3) Analyze the effect of rockfall on the performance of the Richards Barrier and the depth of the barrier required to protect waste packages under the barrier. (4) Review radiological and heating conditions on placement of multiple layers of the barrier. Subsurface Nuclear Safety personnel will perform calculations to determine the radiation reduction-time relationship and shielding capacity of the barrier. (5) Evaluate the effects of ventilation on cooling of emplacement drifts and

The oxidation behavior of classical thermal barrier coatings exposed to extreme temperature

Directory of Open Access Journals (Sweden)

Alina DRAGOMIRESCU

2017-03-01

Full Text Available Thermal barrier coatings (TBC are designed to protect metal surfaces from extreme temperatures and improve their resistance to oxidation during service. Currently, the most commonly used systems are those that have the TBC structure bond coat (BC / top coat (TC layers. The top coat layer is a ceramic layer. Oxidation tests are designed to identify the dynamics of the thermally oxide layer (TGO growth at the interface of bond coat / top coat layers, delamination mechanism and the TBC structural changes induced by thermal conditions. This paper is a short study on the evolution of aluminum oxide protective layer along with prolonged exposure to the testing temperature. There have been tested rectangular specimens of metal super alloy with four surfaces coated with a duplex thermal barrier coating system. The specimens were microscopically and EDAX analyzed before and after the tests. In order to determine the oxide type, the samples were analyzed using X-ray diffraction. The results of the investigation are encouraging for future studies. The results show a direct relationship between the development of the oxide layer and long exposure to the test temperature. Future research will focus on changing the testing temperature to compare the results.

Influence of supplementary cementitious materials on the properties of concrete for secondary protection barrier in radioactive waste repositories

Czech Academy of Sciences Publication Activity Database

Koťátková, J.; Čáchová, M.; Bezdička, Petr; Vejmelková, E.; Konvalinka, P.; Zemanová, L.; Černý, R.

2018-01-01

Roč. 760, SI (2018), s. 96-101 ISSN 1662-9795. [Special Concrete and Composites 2017 /14./. Lísek, 10.10.2017-11.10.2017] R&D Projects: GA ČR(CZ) GA17-11635S Institutional support: RVO:61388980 Keywords : Basic physical properties * Mechanical properties * Repository * Secondary protection barrier * Supplementary cementitious materials * Thermal properties Subject RIV: CA - Inorganic Chemistry OBOR OECD: Inorganic and nuclear chemistry

Lactobacillus reuteri strains protect epithelial barrier integrity of IPEC-J2 monolayers from the detrimental effect of enterotoxigenic Escherichia coli.

Science.gov (United States)

Karimi, Shokoufeh; Jonsson, Hans; Lundh, Torbjörn; Roos, Stefan

2018-01-01

Lactobacillus reuteri is an inhabitant of the gastrointestinal (GI) tract of mammals and birds and several strains of this species are known to be effective probiotics. The mechanisms by which L. reuteri confers its health-promoting effects are far from being fully understood, but protection of the mucosal barrier is thought to be important. Leaky gut is a state of abnormal intestinal permeability with implications for the pathophysiology of various gastrointestinal disorders. Enterotoxigenic Escherichia coli (ETEC) can invade the intestinal mucosa and induce changes in barrier function by producing enterotoxin or by direct invasion of the intestinal epithelium. Our hypothesis was that L. reuteri can protect the mucosal barrier, and the goal of the study was to challenge this hypothesis by monitoring the protective effect of L. reuteri strains on epithelial dysfunction caused by ETEC. Using an infection model based on the porcine intestinal cell line IPEC-J2, it was demonstrated that pretreatment of the cells with human-derived L. reuteri strains (ATCC PTA 6475, DSM 17938 and 1563F) and a rat strain (R2LC) reduced the detrimental effect of ETEC in a dose-dependent manner, as monitored by permeability of FITC-dextran and transepithelial electrical resistance (TEER). Moreover, the results revealed that ETEC upregulated proinflammatory cytokines IL-6 and TNFα and decreased expression of the shorter isoform of ZO-1 (187 kDa) and E-cadherin. In contrast, pretreatment with L. reuteri DSM 17938 and 1563F downregulated expression of IL-6 and TNFα, and led to an increase in production of the longer isoform of ZO-1 (195 kDa) and maintained E-cadherin expression. Interestingly, expression of ZO-1 (187 kDa) was preserved only when the infected cells were pretreated with strain 1563F. These findings demonstrate that L. reuteri strains exert a protective effect against ETEC-induced mucosal integrity disruption. © 2018 The Authors. Physiological Reports published by

Fire barrier problems-part 3

International Nuclear Information System (INIS)

Verna, B.J.

1993-01-01

This article deals with problems associated with a thermal barrier material called Thermo-Lag 330. Typically in nuclear applications this material is used to provide either 1 hour (1/2 inch thick) or 3 hour (1 inch thick) barriers to prevent the spread of fires between redundant safety systems, and to protect cable trays and conduit. The article reviews concerns within the nuclear industry as to the proper handling of the material, how to interpret the data available on the material, the apparant conflicting assessments of the material when tested by different groups, etc. Research is ongoing on the suitability of the material, but the article points out that the manufacturer feels it should be installed by properly trained installers, the joints sealed with a grouting material, properly bundled to maintain its integrity, have a complete stress skin, and not be walked on after installation in order to function properly

Toll-Like Receptor 2 Activation by beta 2 -> 1-Fructans Protects Barrier Function of T84 Human Intestinal Epithelial Cells in a Chain Length-Dependent Manner

NARCIS (Netherlands)

Vogt, Leonie M.; Meyer, Diederick; Pullens, Gerdie; Faas, Marijke M.; Venema, Koen; Ramasamy, Uttara; Schols, Henk A.; de Vos, Paul

Dietary fiber intake is associated with lower incidence and mortality from disease, but the underlying mechanisms of these protective effects are unclear. We hypothesized that beta 2 -> 1-fructan dietary fibers confer protection on intestinal epithelial cell barrier function via Toll-like receptor 2

Prototype Engineered Barrier System Field Test (PEBSFT)

International Nuclear Information System (INIS)

Ramirez, A.L.; Buscheck, T.; Carlson, R.; Daily, W.; Lee, K.; Lin, Wunan; Mao, Nai-hsien; Ueng, Tzou-Shin; Wang, H.; Watwood, D.

1991-08-01

This final report represents a summary of data and interpretations obtained from the Prototype Engineered Barrier System Field Test (PEBSFT) performed in G-Tunnel within the Nevada Test Site. The PEBSFT was conducted to evaluate the applicability of measurement techniques, numerical models, and procedures developed for future field tests that will be conducted in the Exploratory Studies Facilities (ESF) at Yucca Mountain. The primary objective of the test was to provide a basis for determining whether tests planned for the ESF have the potential to be successful. Chapter 1 on high frequency electromagnetic tomography discusses the rock mass electromagnetic permittivity and attenuation rate changes that were measured to characterize the water distribution in the near field of a simulated waste container. The data are used to obtain quantitative estimates of how the moisture content in the rock mass changes during heating and to infer properties of the spatial variability of water distribution, leading to conclusions about the role of fractures in the system. Chapter 2 discusses the changes in rock moisture content detected by the neutron logging probe. Chapter 3 permeability tests discusses the characterization of the in-situ permeability of the fractured tuff around the borehole. The air permeability testing apparatus, the testing procedures, and the data analysis are presented. Chapter 4 describes the moisture collection system installed in the heater borehole to trap and measure the moisture volumes. Chapter 5 describes relative humidity measurements made with the thermocouple psychrometer and capacitance sensors. Chapter 6 discusses gas pressure measurements in the G-Tunnel, addressing the calibration and installation of piezoresistive-gaged transducers. Chapter 7 describes the calibration and installation of thermocouples for temperature measurements. Chapter 8 discusses the results of the PEBSFT

Analysis of developed transition road safety barrier systems.

Science.gov (United States)

Soltani, Mehrtash; Moghaddam, Taher Baghaee; Karim, Mohamed Rehan; Sulong, N H Ramli

2013-10-01

Road safety barriers protect vehicles from roadside hazards by redirecting errant vehicles in a safe manner as well as providing high levels of safety during and after impact. This paper focused on transition safety barrier systems which were located at the point of attachment between a bridge and roadside barriers. The aim of this study was to provide an overview of the behavior of transition systems located at upstream bridge rail with different designs and performance levels. Design factors such as occupant risk and vehicle trajectory for different systems were collected and compared. To achieve this aim a comprehensive database was developed using previous studies. The comparison showed that Test 3-21, which is conducted by impacting a pickup truck with speed of 100 km/h and angle of 25° to transition system, was the most severe test. Occupant impact velocity and ridedown acceleration for heavy vehicles were lower than the amounts for passenger cars and pickup trucks, and in most cases higher occupant lateral impact ridedown acceleration was observed on vehicles subjected to higher levels of damage. The best transition system was selected to give optimum performance which reduced occupant risk factors using the similar crashes in accordance with Test 3-21. Copyright © 2013 Elsevier Ltd. All rights reserved.

Design and construction of a deep slurry trench barrier

International Nuclear Information System (INIS)

Deming, P.W.

1997-01-01

A 24 m (80 ft) deep slurry trench surrounding a former chromium manufacturing facility on the Patapsco River in Baltimore, Maryland was constructed in 1995 to contain groundwater and site Soils, and to reduce the volume of groundwater extracted to maintain an inward gradient. In 1992, an embankment made of crushed stone was constructed in the Patapsco River to make land for barrier construction outboard of the bulkheads, and to protect the barrier. Stability of the slurry-supported trench excavation in the embankment required construction from an elevated work platform. An extended reach backhoe was used to excavate the deep slurry trench and to clean the trench bottom. Soil-Bentonite backfill was prepared at a central mixing area and transported by truck to the perimeter barrier. A synthetic membrane was inserted partially into the backfill for connection to a multimedia cap, and for redundancy and erosion control in the tidal zone. Hydraulic testing of the aquitard contained by the barrier demonstrated excellent performance of the barrier and bottom closure. Detailed definition of subsurface conditions and the closure stratum was necessary for the design and successful construction of the barrier, and is recommended for comparable slurry trench construction projects

Performance study of protective clothing against hot water splashes: from bench scale test to instrumented manikin test.

Science.gov (United States)

Lu, Yehu; Song, Guowen; Wang, Faming

2015-03-01

Hot liquid hazards existing in work environments are shown to be a considerable risk for industrial workers. In this study, the predicted protection from fabric was assessed by a modified hot liquid splash tester. In these tests, conditions with and without an air spacer were applied. The protective performance of a garment exposed to hot water spray was investigated by a spray manikin evaluation system. Three-dimensional body scanning technique was used to characterize the air gap size between the protective clothing and the manikin skin. The relationship between bench scale test and manikin test was discussed and the regression model was established to predict the overall percentage of skin burn while wearing protective clothing. The results demonstrated strong correlations between bench scale test and manikin test. Based on these studies, the overall performance of protective clothing against hot water spray can be estimated on the basis of the results of the bench scale hot water splashes test and the information of air gap size entrapped in clothing. The findings provide effective guides for the design and material selection while developing high performance protective clothing. Published by Oxford University Press on behalf of the British Occupational Hygiene Society 2014.

Control of Eolian soil erosion from waste site surface barriers

International Nuclear Information System (INIS)

Ligotke, M.W.

1994-11-01

Physical models were tested in a wind tunnel to determine optimum surface-ravel admixtures for protecting silt-loam soil from erosion by, wind and saltating, sand stresses. The tests were performed to support the development of a natural-material surface barrier for and waste sites. Plans call for a 2-m deep silt-loam soil reservoir to retain infiltrating water from rainfall and snowmelt. The objective of the study was to develop a gravel admixture that would produce an erosion-resistant surface layer during, periods of extended dry climatic stress. Thus, tests were performed using simulated surfaces representing dry, unvegetated conditions present just after construction, after a wildfire, or during an extended drought. Surfaces were prepared using silt-loam soil mixed with various grades of sand and Travel. Wind-induced surface shear stresses were controlled over the test surfaces, as were saltating, sand mass flow rates and intensities. Tests were performed at wind speeds that approximated and exceeded local 100-year peak gust intensities. Surface armors produced by pea gravel admixtures were shown to provide the best protection from wind and saltating sand stresses. Compared with unprotected silt-loam surfaces, armored surfaces reduced erosion rates by more than 96%. Based in part on wind tunnel results, a pea gravel admixture of 15% will be added to the top 1 in of soil in a prototype barrier under construction in 1994. Field tests are planned at the prototype site to provide data for comparison with wind tunnel results

Study on the saturating and swelling behavior of an engineering bentonite barrier using a test model

International Nuclear Information System (INIS)

Nakajima, Makoto; Kobayashi, Ichizo; Toida, Masaru; Fujisaki, Katsutoshi

2007-01-01

The conceptual design of a disposal facility with additional buffer depth for radioactive waste is mainly constituted from the multi-barrier system that is constructed around the waste form so that it prevents radionuclide transfer to the biosphere. The engineered bentonite barrier is one of the elements of the multi-barrier system and is constructed with homogeneous bentonite-containing material compacted to a high density so that there are no voids. Due to the swelling characteristics of the bentonite material, the self-sealing function which is an important function of the bentonite barrier can work, but at the same time it mechanically affects the neighboring structures. Therefore, an experimental study was implemented in order to evaluate the mechanical effect of the bentonite swelling behavior throughout the construction, emplacement operations and closure re-saturation phase. In this article, the results of swelling tests to obtain the mechanical properties of the bentonite and three types of test model experiments performed for the event observations in the different saturation processes are described. As a result, the effects of a seepage pattern of ground water and a variation in the density produced by construction on the swelling pressure distribution of the bentonite barrier could be reproduced and validated. It is thought that they will be important events when ground water permeates the bentonite layer of a multiple barrier system. (author)

Effect of disposable infection control barriers on light output from dental curing lights.

Science.gov (United States)

Scott, Barbara A; Felix, Corey A; Price, Richard B T

2004-02-01

To prevent contamination of the light guide on a dental curing light, barriers such as disposable plastic wrap or covers may be used. This study compared the effect of 3 disposable barriers on the spectral output and power density from a curing light. The hypothesis was that none of the barriers would have a significant clinical effect on the spectral output or the power density from the curing light. Three disposable barriers were tested against a control (no barrier). The spectra and power from the curing light were measured with a spectrometer attached to an integrating sphere. The measurements were repeated on 10 separate occasions in a random sequence for each barrier. Analysis of variance (ANOVA) followed by Fisher's protected least significant difference test showed that the power density was significantly less than control (by 2.4% to 6.1%) when 2 commercially available disposable barriers were used (p 0.05). The effect of each of the barriers on the power output was small and probably clinically insignificant. ANOVA comparisons of mean peak wavelength values indicated that none of the barriers produced a significant shift in the spectral output relative to the control ( p > 0.05). Two of the 3 disposable barriers produced a significant reduction in power density from the curing light. This drop in power was small and would probably not adversely affect the curing of composite resin. None of the barriers acted as light filters.

Prototype Engineered Barrier System Field Tests (PEBSFT)

International Nuclear Information System (INIS)

Ramirez, A.L.; Wilder, D.G.

1991-02-01

This progress report presents the interpretation of data obtained (up to November 1, 1988) from the Prototype Engineered Barrier System Field Tests (PEBSFT) that are being performed for the Yucca Mountain Project (YMP) in G-Tunnel within the Nevada Test site. The PEBSFTs are being conducted to evaluate the applicability of measurement techniques, numerical models, and procedures developed for the field tests for future investigations that will be conducted in the Exploratory Shaft Facilities, at a potential high-level radioactive waste repository site in Yucca Mountain. The primary objective of the tests is to provide the basis for determining whether tests planned for Yucca Mountain have the potential to be successful. Thirteen chapters discuss the following: mapping the electromagnetic permittivity and attenuation rate of the rock mass; changes in moisture content detected by the neutron logging probe; characterization of the in-situ permeability of the fractured tuff around the heater borehole; electrical resistance heater installed in a 30-cm borehole; relative humidity measurements; the operation, design, construction, calibration, and installation of a microwave circuit that might provide partial pressure information at temperatures in excess of 200 degree C (392 degree F); pressure and temperature measurements in the G-Tunnel; the moisture collection system, which attempts to collect steam that migrates into the heater borehole; The borehole television and borescope surveys that were performed to map the location, orientation, and aperture of the fractures intersecting the boreholes; preliminary scoping calculations of the hydrothermal conditions expected for this prototype test; the Data Acquisition System; and the results of the PEBSFT, preliminary interpretations of these results, and plans for the remainder of the test. Chapters have been indexed separately for inclusion on the data base

SOME OBSERVATIONS ON THE DESIGN OF NOISE BARRIERS

Directory of Open Access Journals (Sweden)

Arkadiusz BOCZKOWSKI

2013-04-01

Full Text Available The issue connected with effectiveness of noise barriers has been the subject of numerous considerations among acousticians. On the one hand, noise barriers are still the most popular and the most frequently used protection against traffic noise, on the other hand, however, the excessive number of noise barriers and the results of research focusing on effectiveness of the existing barriers make us reflect whether it is reasonable to use them. Very often low effectiveness of noise barriers is related to a badly conducted designing process. This article presents the basic mistakes made by noise barriers’ designers and the consequences thereof. Next, the paper describes the appropriate approach to the process of the noise barriers’ design which consists in the use of computer methods and conducting of a detailed analysis of the acoustic field’s distribution both behind the barrier and on the facades of the acoustically protected buildings.

Socio-Structural Barriers, Protective Factors, and HIV Risk Among Central-Asian Female Migrants in Moscow

Directory of Open Access Journals (Sweden)

Christopher Zabrocki

2013-07-01

Full Text Available Objective: This study aimed to build formative knowledge on socio-structural barriers, protective factors, and HIV sexual risk amongst Central-Asian female migrants in Moscow. Methods: Data collection included ethnographic interviews in Moscow with a purposive sample of 30 unmarried female migrants, 15 from Kyrgyzstan and 15 from Tajikistan. Results: Study participants reported difficulties with acquiring documents for legal status, financial insecurity, discrimination, sexual harassment, and lack of support. Based on analysis of the cases, one pathway linked lack of legal documentation and instrumental support with elevated sexual risk. Another pathways linked traditional cultural attitudes with both no and moderate sexual risk. Conclusion: Future HIV prevention efforts with Central Asian female migrants in Moscow should be multilevel and include: increasing HIV and prevention knowledge and skills, promoting condom use with regular partners, identifying and supporting cultural attitudes that protect against HIV sexual risk behaviors, facilitating legal status, building community support, and increasing economic options.

Barriers to the future

Energy Technology Data Exchange (ETDEWEB)

Massey, C T

1986-09-01

Opportunities for the British coal industry seem vast yet there are still barriers to progress. Seven areas are identified and discussed: mining mobility (for example, longwall mining systems are rigid and inflexible compared with American stall and pillar working); mine structure (many mines are more suitable to pit ponies than to large pieces of equipment); financial barriers (Government requires the industry to break even in 1987/88); personnel barriers (less specialization, better use of skills); safety barriers (increased use of remote control, ergonomics and robotics to protect workers); microelectronic management (nationalization has cushioned management from the market place; there is a need for a more multidisciplinary approach to the industry); and legal barriers (most legislation in the past has been in response to accidents; legislation external to the industry but affecting it is more fundamental).

Note: Inhibiting bottleneck corrosion in electrical calcium tests for ultra-barrier measurements

Energy Technology Data Exchange (ETDEWEB)

Nehm, F., E-mail: frederik.nehm@iapp.de; Müller-Meskamp, L.; Klumbies, H.; Leo, K. [Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Straße 1, 01069 Dresden (Germany)

2015-12-15

A major failure mechanism is identified in electrical calcium corrosion tests for quality assessment of high-end application moisture barriers. Accelerated calcium corrosion is found at the calcium/electrode junction, leading to an electrical bottleneck. This causes test failure not related to overall calcium loss. The likely cause is a difference in electrochemical potential between the aluminum electrodes and the calcium sensor, resulting in a corrosion element. As a solution, a thin, full-area copper layer is introduced below the calcium, shifting the corrosion element to the calcium/copper junction and inhibiting bottleneck degradation. Using the copper layer improves the level of sensitivity for the water vapor transmission rate (WVTR) by over one order of magnitude. Thin-film encapsulated samples with 20 nm of atomic layer deposited alumina barriers this way exhibit WVTRs of 6 × 10{sup −5} g(H{sub 2}O)/m{sup 2}/d at 38 °C, 90% relative humidity.

Barriers to, and emerging strategies for, HIV testing among adolescents in sub-Saharan Africa.

Science.gov (United States)

Chikwari, Chido D; Dringus, Stefanie; Ferrand, Rashida A

2018-05-01

HIV/AIDS is one of the leading causes of death among adolescents in sub-Saharan Africa and 40% of new HIV infections worldwide occur in this group. HIV testing and counselling (HTC) is the critical first step to accessing HIV treatment. The prevalence of undiagnosed HIV infection is substantially higher in adolescents compared with adults. We review barriers to HTC for adolescents and emerging HTC strategies appropriate to adolescents in sub-Saharan Africa. There are substantial individual, health system and legal barriers to HTC among adolescents, and stigma by providers and communities remains an important obstacle. There has been progress made in recent years in developing strategies that address some of these barriers, increase uptake of HTC and yield of HIV. These include targeted approaches focused on provision of HTC among those higher risk of being infected, for example, index-linked HTC and use of screening tools to identify those at risk of HIV. Community-based HIV-testing approaches including HIV self-testing and incentives have also been shown to increase uptake of HTC. In implementing HTC strategies, consideration must be given to scalability and cost-effectiveness. HTC approaches must be coupled with linkage to appropriate care and prevention services.

Effect of Remote Back-Up Protection System Failure on the Optimum Routine Test Time Interval of Power System Protection

Directory of Open Access Journals (Sweden)

Y Damchi

2013-12-01

Full Text Available Appropriate operation of protection system is one of the effective factors to have a desirable reliability in power systems, which vitally needs routine test of protection system. Precise determination of optimum routine test time interval (ORTTI plays a vital role in predicting the maintenance costs of protection system. In the most previous studies, ORTTI has been determined while remote back-up protection system was considered fully reliable. This assumption is not exactly correct since remote back-up protection system may operate incorrectly or fail to operate, the same as the primary protection system. Therefore, in order to determine the ORTTI, an extended Markov model is proposed in this paper considering failure probability for remote back-up protection system. In the proposed Markov model of the protection systems, monitoring facility is taken into account. Moreover, it is assumed that the primary and back-up protection systems are maintained simultaneously. Results show that the effect of remote back-up protection system failures on the reliability indices and optimum routine test intervals of protection system is considerable.

An oncological view on the blood-testis barrier

NARCIS (Netherlands)

Bart, J; Groen, HJM; van der Graaf, WTA; Hollema, H; Hendrikse, NH; Vaalburg, W; Sleijfer, DT; de Vries, EGE

The function of the blood-testis barrier is to protect germ cells from harmful influences; thus, it also impedes the delivery of chemotherapeutic drugs to the testis. The barrier has three components: first, a physicochemical barrier consisting of continuous capillaries, Sertoli cells in the tubular

Bentonite engineered barrier building method for radioactive waste on sub-surface disposal test project

International Nuclear Information System (INIS)

Mori, Takuo; Takahashi, Shinichi; Takeuchi, Kunifumi; Namiki, Kazuto

2008-01-01

The engineering barriers such as clay and concrete materials are planned to use for covering radioactive waste in cavern-type disposal facility. The requirement to clay barrier is very low permeability, which could be satisfied by high density Bentonite, and such a compaction method will be needed. Two methods, compaction and air shot, were tested in engineering scale for constructing a high-density clay barrier. Two types of compaction equipments, 'Teasel plate' and 'Plate compacter', were developed and engineering scale experiments were performed for compacting Bentonite only and Bentonite-sand-aggregate mixture. As a result, the Teasel plate can reach higher density Bentonite in relatively short time in comparison to other equipments. While, regarding air shot method, an air-shot machine in a tunnel construction site was tested by different water adding methods (wet, dry, and half wet). It is concluded that the dry and half wet constructing methods will achieve reasonable workability. As a result, the best construction option can be chosen according to the locations of radioactive waste facility. (author)

Devices for overcoming biological barriers: the use of physical forces to disrupt the barriers.

Science.gov (United States)

Mitragotri, Samir

2013-01-01

Overcoming biological barriers including skin, mucosal membranes, blood brain barrier as well as cell and nuclear membrane constitutes a key hurdle in the field of drug delivery. While these barriers serve the natural protective function in the body, they limit delivery of drugs into the body. A variety of methods have been developed to overcome these barriers including formulations, targeting peptides and device-based technologies. This review focuses on the use of physical methods including acoustic devices, electric devices, high-pressure devices, microneedles and optical devices for disrupting various barriers in the body including skin and other membranes. A summary of the working principles of these devices and their ability to enhance drug delivery is presented. Copyright © 2012. Published by Elsevier B.V.

When access is an issue: exploring barriers to predictive testing for Huntington disease in British Columbia, Canada.

Science.gov (United States)

Hawkins, Alice K; Creighton, Susan; Hayden, Michael R

2013-02-01

Predictive testing (PT) for Huntington disease (HD) requires several in-person appointments. This requirement may be a barrier to testing so that at risk individuals do not realize the potential benefits of PT. To understand the obstacles to PT in terms of the accessibility of services, as well as exploring mechanisms by which this issue may be addressed, we conducted an interview study of individuals at risk for HD throughout British Columbia, Canada. Results reveal that the accessibility of PT can be a barrier for two major reasons: distance and the inflexibility of the testing process. Distance is a structural barrier, and relates to the time and travel required to access PT, the financial and other opportunity costs associated with taking time away from work and family to attend appointments and the stress of navigating urban centers. The inflexibility of the testing process barrier relates to the emotional and psychological accessibility of PT. The results of the interview study reveal that there are access barriers to PT that deter individuals from receiving the support, information and counseling they require. What makes accessibility of PT services important is not just that it may result in differences in quality of life and care, but because these differences may be addressed with creative and adaptable solutions in the delivery of genetic services. The study findings underscore the need for us to rethink and personalize the way we deliver such services to improve access issues to prevent inequities in the health care system.

The use of protective barriers to deter inadvertent human intrusion into a mined geologic facility for the disposal of radioactive waste: A review of previous investigations and potential concepts

International Nuclear Information System (INIS)

Tolan, T.L.

1993-06-01

Sandia National Laboratories is evaluating the feasibility of developing protective barrier system for the Waste Isolation Pilot Plant (WIPP) to thwart inadvertent human intrusion into this radioactive-waste disposal system for a period of 9,900 years after assumed loss of active institutional controls. The protective barrier system would be part of a series of enduring passive institutional controls whose long-term function will be to reduce the likelihood of inadvertent human activities (e.g., exploratory drilling for resources) that could disrupt the WIPP disposal system

Knowledge of carrier status and barriers to testing among mothers of sons with Duchenne or Becker muscular dystrophy.

Science.gov (United States)

Bogue, Lauren; Peay, Holly; Martin, Ann; Lucas, Ann; Ramchandren, Sindhu

2016-12-01

Our study objective was to survey female carriers for Duchenne and Becker muscular dystrophy to identify barriers to carrier testing and the impact of carrier risk knowledge on cardiac and reproductive health management. We surveyed women who have or had biological sons with Duchenne or Becker muscular dystrophy and were enrolled in the US DuchenneConnect patient registry, with questions assessing knowledge of carrier status and recurrence risk, knowledge of care standards for carriers, and barriers to testing. Of the 182 eligible respondents, 25% did not know their carrier status and 14% incorrectly classified themselves as not at risk. Cost of testing was the most commonly identified barrier to testing. Women reporting unknown carrier status were 13 times as likely to express uncertainty regarding their recurrence risk compared to women reporting positive carrier status. 37% of women at an increased risk for cardiomyopathy had never had an echocardiogram. Women who were certain of their positive carrier status were twice as likely to have had an echocardiogram in the last five years compared to women with unknown carrier status. Future research on reducing barriers to counseling and carrier testing, such as cost, may improve care standard adherence. Copyright © 2016 Elsevier B.V. All rights reserved.

Accelerated Test Method for Corrosion Protective Coatings

Data.gov (United States)

National Aeronautics and Space Administration — This project seeks to develop a new accelerated corrosion test method that predicts the long-term corrosion protection performance of spaceport structure coatings as...

Barriers for HIV testing during pregnancy in Southern Brazil

Directory of Open Access Journals (Sweden)

Humberto Rosa

2006-04-01

Full Text Available OBJECTIVE: To assess HIV testing rate and determine risk factors for not have been tested during pregnancy. METHODS: A cross-sectional study was carried out in Porto Alegre, Southern Brazil, from December 2000 to February 2001. Socioeconomic, maternal and healthcare variables were obtained by means of a standardized questionnaire. Crude and adjusted odds ratios and their 95% confidence intervals were obtained in logistic regression models. RESULTS: A total of 1,642 mothers were interviewed. Of them, 94.3% reported being offered HIV testing before or during pregnancy or during labor; 89 mothers (5.4% were not tested or did not know if they were tested. Attending fewer than six prenatal visits, being single and younger than 18 years old were relevant barriers preventing HIV testing. There was found a relationship between maternal schooling and the category of prenatal care provider. Having low 22.20 (12.43-39.67 or high 3.38 (1.86-7.68. schooling and being cared in the private sector strongly reduced the likelihood of being HIV tested. CONCLUSIONS: The Brazilian Health Ministry's recommendation for universal counseling and HIV testing has been successfully implemented in the public sector. In order to improve HIV testing coverage, new strategies need to target women cared in the private sector especially those of low schooling.

Barriers for HIV testing during pregnancy in Southern Brazil

Directory of Open Access Journals (Sweden)

Rosa Humberto

2006-01-01

Full Text Available OBJECTIVE: To assess HIV testing rate and determine risk factors for not have been tested during pregnancy. METHODS: A cross-sectional study was carried out in Porto Alegre, Southern Brazil, from December 2000 to February 2001. Socioeconomic, maternal and healthcare variables were obtained by means of a standardized questionnaire. Crude and adjusted odds ratios and their 95% confidence intervals were obtained in logistic regression models. RESULTS: A total of 1,642 mothers were interviewed. Of them, 94.3% reported being offered HIV testing before or during pregnancy or during labor; 89 mothers (5.4% were not tested or did not know if they were tested. Attending fewer than six prenatal visits, being single and younger than 18 years old were relevant barriers preventing HIV testing. There was found a relationship between maternal schooling and the category of prenatal care provider. Having low 22.20 (12.43-39.67 or high 3.38 (1.86-7.68. schooling and being cared in the private sector strongly reduced the likelihood of being HIV tested. CONCLUSIONS: The Brazilian Health Ministry's recommendation for universal counseling and HIV testing has been successfully implemented in the public sector. In order to improve HIV testing coverage, new strategies need to target women cared in the private sector especially those of low schooling.

Provider-related barriers to rapid HIV testing in U.S. urban non-profit community clinics, community-based organizations (CBOs) and hospitals.

Science.gov (United States)

Bogart, Laura M; Howerton, Devery; Lange, James; Setodji, Claude Messan; Becker, Kirsten; Klein, David J; Asch, Steven M

2010-06-01

We examined provider-reported barriers to rapid HIV testing in U.S. urban non-profit community clinics, community-based organizations (CBOs), and hospitals. 12 primary metropolitan statistical areas (PMSAs; three per region) were sampled randomly, with sampling weights proportional to AIDS case reports. Across PMSAs, all 671 hospitals and a random sample of 738 clinics/CBOs were telephoned for a survey on rapid HIV test availability. Of the 671 hospitals, 172 hospitals were randomly selected for barriers questions, for which 158 laboratory and 136 department staff were eligible and interviewed in 2005. Of the 738 clinics/CBOs, 276 were randomly selected for barriers questions, 206 were reached, and 118 were eligible and interviewed in 2005-2006. In multivariate models, barriers regarding translation of administrative/quality assurance policies into practice were significantly associated with rapid HIV testing availability. For greater rapid testing diffusion, policies are needed to reduce administrative barriers and provide quality assurance training to non-laboratory staff.

Emergent Behavior of Coupled Barrier Island - Resort Systems

Science.gov (United States)

McNamara, D. E.; Werner, B. T.

2004-12-01

Barrier islands are attractive sites for resorts. Natural barrier islands experience beach erosion and island overwash during storms, beach accretion and dune building during inter-storm periods, and migration up the continental shelf as sea level rises. Beach replenishment, artificial dune building, seawalls, jetties and groins have been somewhat effective in protecting resorts against erosion and overwash during storms, but it is unknown how the coupled system will respond to long-term sea level rise. We investigate coupled barrier island - resort systems using an agent-based model with three components: natural barrier islands divided into a series of alongshore cells; resorts controlled by markets for tourism and hotel purchases; and coupling via storm damage to resorts and resort protection by government agents. Modeled barrier islands change by beach erosion, island overwash and inlet cutting during storms, and beach accretion, tidal delta growth and dune and vegetation growth between storms. In the resort hotel market, developer agents build hotels and hotel owning agents purchase them using predictions of future revenue and property appreciation, with the goal of maximizing discounted utility. In the tourism market, hotel owning agents set room rental prices to maximize profit and tourist agents choose vacation destinations maximizing a utility based on beach width, price and word-of-mouth. Government agents build seawalls, groins and jetties, and widen the beach and build up dunes by adding sand to protect resorts from storms, enhance beach quality, and maximize resort revenue. Results indicate that barrier islands and resorts evolve in a coupled manner to resort size saturation, with resorts protected against small-to-intermediate-scale storms under fairly stable sea level. Under extended, rapidly rising sea level, protection measures enhance the effect of large storms, leading to emergent behavior in the form of limit cycles or barrier submergence

Wave basin model tests of technical-biological bank protection

Science.gov (United States)

Eisenmann, J.

2012-04-01

Sloped embankments of inland waterways are usually protected from erosion and other negative im-pacts of ship-induced hydraulic loads by technical revetments consisting of riprap. Concerning the dimensioning of such bank protection there are several design rules available, e.g. the "Principles for the Design of Bank and Bottom Protection for Inland Waterways" or the Code of Practice "Use of Standard Construction Methods for Bank and Bottom Protection on Waterways" issued by the BAW (Federal Waterways Engineering and Research Institute). Since the European Water Framework Directive has been put into action special emphasis was put on natural banks. Therefore the application of technical-biological bank protection is favoured. Currently design principles for technical-biological bank protection on inland waterways are missing. The existing experiences mainly refer to flowing waters with no or low ship-induced hydraulic loads on the banks. Since 2004 the Federal Waterways Engineering and Research Institute has been tracking the re-search and development project "Alternative Technical-Biological Bank Protection on Inland Water-ways" in company with the Federal Institute of Hydrology. The investigation to date includes the ex-amination of waterway sections where technical- biological bank protection is applied locally. For the development of design rules for technical-biological bank protection investigations shall be carried out in a next step, considering the mechanics and resilience of technical-biological bank protection with special attention to ship-induced hydraulic loads. The presentation gives a short introduction into hydraulic loads at inland waterways and their bank protection. More in detail model tests of a willow brush mattress as a technical-biological bank protec-tion in a wave basin are explained. Within the scope of these tests the brush mattresses were ex-posed to wave impacts to determine their resilience towards hydraulic loads. Since the

Field tests on migration of TRU-nuclide, (2). Migration test for engineered barrier materials in aerated soil

International Nuclear Information System (INIS)

Maeda, Toshikatsu; Tanaka, Tadao; Mukai, Masayuki

2003-01-01

Field tests on migration of radionuclides for engineered barrier materials such as bentonite and cementitious materials were performed. The tests were run under both wet conditions with artificial rainfall and dry conditions with natural rainfall. Laboratory experiments such as batch adsorption tests were also conducted to analyze the result of field test. The results of field tests agreed with the predicted moisture conditions and the migration behaviors observed at the laboratory experiment that is reported so far. For bentonite material, the movements of the tracer were calculated using known information such as the results of batch sorption tests and migration mechanism. Comparing the result of field test and calculations, it is suggested that tracer migration behavior in bentonite material in field can be evaluated quantitatively by the known migration mechanism and the results of laboratory experiments such as batch sorption test. (author)

Acceptability and Barriers to Uptake of Voluntary Counselling and Testing for HIV amongst Pregnant Women in Nigeria

Directory of Open Access Journals (Sweden)

Bukola Olateju Omolase

2010-08-01

Full Text Available AIM: This study was designed to determine the acceptability of voluntary counselling and testing (VCT for HIV and identify possible barriers to it’s uptake amongst pregnant women in a Nigerian community. METHODS: One hundred and twenty seven consenting pregnant women attending antenatal clinic at Federal Medical Centre, Owo were randomly selected and interviewed by the authors and two trained assistants. The study was conducted between August and October, 2007. The information obtained with the aid of semi –structured questionnaire included their bio data, awareness about VCT and vertical transmission of HIV-AIDS. Other information obtained included acceptability of VCT and barriers to its uptake. RESULT: Majority (85% were aware about vertical transmission of HIV, most (83.5% knew of VCT. They were predominantly willing to accept VCT (77.2% and were ready to recommend VCT to others(76.2%. The main identified barriers to uptake of voluntary counseling were fear of possible outcome (82.7% and risk of divorce (70.9%. CONCLUSION: Most respondents were aware of voluntary counselling and testing for HIV as well as the vertical transmission of HIV. Majority were willing to accept HIV test and recommend same to others. Barriers to uptake of HIV test included fear of possible outcome, lack of felt need, stigmatization and financial constraint. There is need to extend voluntary counselling and testing for HIV to all antenatal patients. [TAF Prev Med Bull 2010; 9(4.000: 309-314

Potential in vitro model for testing the effect of exposure to nanoparticles on the lung alveolar epithelial barrier

Directory of Open Access Journals (Sweden)

Raymond Derk

2015-03-01

Full Text Available Pulmonary barrier function plays a pivotal role in protection from inhaled particles. However, some nano-scaled particles, such as carbon nanotubes (CNT, have demonstrated the ability to penetrate this barrier in animal models, resulting in an unusual, rapid interstitial fibrosis. To delineate the underlying mechanism and specific bio-effect of inhaled nanoparticles in respiratory toxicity, models of lung epithelial barriers are required that allow accurate representation of in vivo systems; however, there is currently a lack of consistent methods to do so. Thus, this work demonstrates a well-characterized in vitro model of pulmonary barrier function using Calu-3 cells, and provides the experimental conditions required for achieving tight junction complexes in cell culture, with trans-epithelial electrical resistance measurement used as a biosensor for proper barrier formation and integrity. The effects of cell number and serum constituents have been examined and we found that changes in each of these parameters can greatly affect barrier formation. Our data demonstrate that use of 5.0 × 104 Calu-3 cells/well in the Transwell cell culture system, with 10% serum concentrations in culture media is optimal for assessing epithelial barrier function. In addition, we have utilized CNT exposure to analyze the dose-, time-, and nanoparticle property-dependent alterations of epithelial barrier permeability as a means to validate this model. Such high throughput in vitro cell models of the epithelium could be used to predict the interaction of other nanoparticles with lung epithelial barriers to mimic respiratory behavior in vivo, thus providing essential tools and bio-sensing techniques that can be uniformly employed.

Financial Strain and Regional Unemployment as Barriers to Job Search Self-Efficacy: A Test of Social Cognitive Career Theory

Science.gov (United States)

Dahling, Jason J.; Melloy, Robert; Thompson, Mindi N.

2013-01-01

Social cognitive career theory (SCCT) emphasizes the potential impact of contextual barriers on vocational self-efficacy, interests, and goals. However, most tests of SCCT to date have focused exclusively on person-level, perceptual barriers rather than objective, macroeconomic barriers that may influence large groups of people. In this study, we…

Thermal Conductivity of Ceramic Thermal Barrier and Environmental Barrier Coating Materials

Science.gov (United States)

Zhu, Dong-Ming; Bansal, Narottam P.; Lee, Kang N.; Miller, Robert A.

2001-01-01

Thermal barrier and environmental barrier coatings (TBC's and EBC's) have been developed to protect metallic and Si-based ceramic components in gas turbine engines from high temperature attack. Zirconia-yttria based oxides and (Ba,Sr)Al2Si2O8(BSAS)/mullite based silicates have been used as the coating materials. In this study, thermal conductivity values of zirconia-yttria- and BSAS/mullite-based coating materials were determined at high temperatures using a steady-state laser heat flux technique. During the laser conductivity test, the specimen surface was heated by delivering uniformly distributed heat flux from a high power laser. One-dimensional steady-state heating was achieved by using thin disk specimen configuration (25.4 mm diam and 2 to 4 mm thickness) and the appropriate backside air-cooling. The temperature gradient across the specimen thickness was carefully measured by two surface and backside pyrometers. The thermal conductivity values were thus determined as a function of temperature based on the 1-D heat transfer equation. The radiation heat loss and laser absorption corrections of the materials were considered in the conductivity measurements. The effects of specimen porosity and sintering on measured conductivity values were also evaluated.

Chemical conversion coating for protecting magnesium alloys from corrosion

Science.gov (United States)

Bhargava, Gaurang; Allen, Fred M.; Skandan, Ganesh; Hornish, Peter; Jain, Mohit

2016-01-05

A chromate-free, self-healing conversion coating solution for magnesium alloy substrates, composed of 10-20 wt. % Mg(NO.sub.3).sub.2.6H.sub.2O, 1-5 wt. % Al(NO.sub.3).sub.3.9H.sub.2O, and less than 1 wt. % of [V.sub.10O.sub.28].sup.6- or VO.sub.3.sup.- dissolved in water. The corrosion resistance offered by the resulting coating is in several hundreds of hours in salt-spray testing. This prolonged corrosion protection is attributed to the creation of a unique structure and morphology of the conversion coating that serves as a barrier coating with self-healing properties. Hydroxoaluminates form the backbone of the barrier protection offered while the magnesium hydroxide domains facilitate the "slow release" of vanadium compounds as self-healing moieties to defect sites, thus providing active corrosion protection.

Evaluation of Subsurface Engineered Barriers at Waste Sites

National Research Council Canada - National Science Library

1998-01-01

.... Environmental Protection Agency's (EPA) waste programs with a national retrospective analysis of barrier field performance, and information that may be useful in developing guidance on the use and evaluation of barrier systems...

Manufacture and test of prototype water pipe chase barrier in ITER Magnet Feeder system

Energy Technology Data Exchange (ETDEWEB)

Lu, Kun, E-mail: lukun@ipp.ac.cn [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Wen, Xinjie; Liu, Chen; Song, Yuntao [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Niu, Erwu [ITER China, 15B Fuxing Road, Beijing 100862 (China); Gung, Chenyu; Su, Man [ITER Organization, Route de Vinon-sur-Verdon – CS 90046, 13067 St Paul-lez-Durance Cedex (France)

2016-11-01

The Magnet Feeder system in the International Thermonuclear Experimental Reactor (ITER) deploys electrical currents and supercritical helium to the superconducting magnets and the magnet diagnostic signals to the operators. In the current design, the feeders located in the upper L3 level of the Tokamak gallery penetrate the Tokamak coolant water system vault, the biological shield and the cryostat. As a secondary confinement to contain the activated coolant water in the vault in the case of water pipe burst accident, a water barrier is welded between the penetration in the water pipe chase outer wall and the mid-plane of the vacuum jacket of the Feeder Coil Terminal Box (CTB). A thin-wall stainless steel diaphragm with an omega shape profile is welded around the CTB as the water barrier to endure 2 bar hydraulic pressure. In addition, the barrier is designed as a flexible compensator to withstand a maximum of 15 mm of axial displacement of the CTB in case of helium leak accident without failure. This paper presents the detail configuration, the manufacturing and assembly processes of the water barrier. Test results of the prototype water barrier under simulated accident conditions are also reported. Successful qualification of the design and manufacturing process of the water barrier lays a good foundation for the series production of this subsystem.

Test Plan to Assess Fire Effects on the Function of an Engineered Surface Barrier

International Nuclear Information System (INIS)

Ward, Anderson L.; Berlin, Gregory T.; Cammann, Jerry W.; Leary, Kevin D.; Link, Steven O.

2008-01-01

Wildfire is a frequent perturbation in shrub steppe ecosystems, altering the flora, fauna, atmosphere, and soil of these systems. Research on the fire effects has focused mostly on natural ecosystems with essentially no attention on engineered systems like surface barriers. The scope of the project is to use a simulated wildfire to induce changes in an engineered surface barrier and document the effects on barrier performance. The main objective is to quantify the effects of burning and the resulting post-fire conditions on alterations in soil physical properties; hydrologic response, particularly the water balance; geochemical properties; and biological properties. A secondary objective is to use the lessons learned to maximize fire protection in the design of long-term monitoring systems based on electronic sensors. A simulated wildfire will be initiated, controlled and monitored at the 200-BP-1 barrier in collaboration with the Hanford Fire Department during the fall of 2008. The north half of the barrier will be divided into nine 12 x 12 m plots, each of which will be randomly assigned a fuel load of 2 kg m-2 or 4 kg m-2. Each plot will be ignited around the perimeter and flames allowed to carry to the centre. Any remaining unburned vegetation will be manually burned off using a drip torch. Progress of the fire and its effects will be monitored using point measurements of thermal, hydrologic, and biotic variables. Three measures of fire intensity will be used to characterize fire behavior: (1) flame height, (2) the maximum temperature at three vertical profile levels, and (3) total duration of elevated temperature at these levels. Pre-burn plant information, including species diversity, plant height, and canopy diameter will be measured on shrubs from the plots to be burned and from control plots at the McGee ranch. General assessments of shrub survival, recovery, and recruitment will be made after the fire. Near-surface soil samples will be collected pre- and

Test Plan to Assess Fire Effects on the Function of an Engineered Surface Barrier

Energy Technology Data Exchange (ETDEWEB)

Ward, Anderson L.; Berlin, Gregory T.; Cammann, Jerry W.; Leary, Kevin D.; Link, Steven O.

2008-09-29

Wildfire is a frequent perturbation in shrub steppe ecosystems, altering the flora, fauna, atmosphere, and soil of these systems. Research on the fire effects has focused mostly on natural ecosystems with essentially no attention on engineered systems like surface barriers. The scope of the project is to use a simulated wildfire to induce changes in an engineered surface barrier and document the effects on barrier performance. The main objective is to quantify the effects of burning and the resulting post-fire conditions on alterations in soil physical properties; hydrologic response, particularly the water balance; geochemical properties; and biological properties. A secondary objective is to use the lessons learned to maximize fire protection in the design of long-term monitoring systems based on electronic sensors. A simulated wildfire will be initiated, controlled and monitored at the 200-BP-1 barrier in collaboration with the Hanford Fire Department during the fall of 2008. The north half of the barrier will be divided into nine 12 x 12 m plots, each of which will be randomly assigned a fuel load of 2 kg m-2 or 4 kg m-2. Each plot will be ignited around the perimeter and flames allowed to carry to the centre. Any remaining unburned vegetation will be manually burned off using a drip torch. Progress of the fire and its effects will be monitored using point measurements of thermal, hydrologic, and biotic variables. Three measures of fire intensity will be used to characterize fire behavior: (1) flame height, (2) the maximum temperature at three vertical profile levels, and (3) total duration of elevated temperature at these levels. Pre-burn plant information, including species diversity, plant height, and canopy diameter will be measured on shrubs from the plots to be burned and from control plots at the McGee ranch. General assessments of shrub survival, recovery, and recruitment will be made after the fire. Near-surface soil samples will be collected pre- and

Extracellular adenosine-induced Rac1 activation in pulmonary endothelium: Molecular mechanisms and barrier-protective role.

Science.gov (United States)

Kovacs-Kasa, Anita; Kim, Kyung Mi; Cherian-Shaw, Mary; Black, Stephen M; Fulton, David J; Verin, Alexander D

2018-08-01

We have previously shown that Gs-coupled adenosine receptors (A2a) are primarily involved in adenosine-induced human pulmonary artery endothelial cell (HPAEC) barrier enhancement. However, the downstream events that mediate the strengthening of the endothelial cell (EC) barrier via adenosine signaling are largely unknown. In the current study, we tested the overall hypothesis that adenosine-induced Rac1 activation and EC barrier enhancement is mediated by Gs-dependent stimulation of cAMP-dependent Epac1-mediated signaling cascades. Adenoviral transduction of HPAEC with constitutively-active (C/A) Rac1 (V12Rac1) significantly increases transendothelial electrical resistance (TER) reflecting an enhancement of the EC barrier. Conversely, expression of an inactive Rac1 mutant (N17Rac1) decreases TER reflecting a compromised EC barrier. The adenosine-induced increase in TER was accompanied by activation of Rac1, decrease in contractility (MLC dephosphorylation), but not Rho inhibition. Conversely, inhibition of Rac1 activity attenuates adenosine-induced increase in TER. We next examined the role of cAMP-activated Epac1 and its putative downstream targets Rac1, Vav2, Rap1, and Tiam1. Depletion of Epac1 attenuated the adenosine-induced Rac1 activation and the increase in TER. Furthermore, silencing of Rac1 specific guanine nucleotide exchange factors (GEFs), Vav2 and Rap1a expression significantly attenuated adenosine-induced increases in TER and activation of Rac1. Depletion of Rap1b only modestly impacted adenosine-induced increases in TER and Tiam1 depletion had no effect on adenosine-induced Rac1 activation and TER. Together these data strongly suggest that Rac1 activity is required for adenosine-induced EC barrier enhancement and that the activation of Rac1 and ability to strengthen the EC barrier depends, at least in part, on cAMP-dependent Epac1/Vav2/Rap1-mediated signaling. © 2017 Wiley Periodicals, Inc.

Protecting the radiation-damaged skin from friction: a mini review

International Nuclear Information System (INIS)

Herst, Patries M

2014-01-01

Radiation-induced skin reactions are an unavoidable side effect of external beam radiation therapy, particularly in areas prone to friction and excess moisture such as the axilla, head and neck region, perineum and skin folds. Clinical studies investigating interventions for preventing or managing these reactions have largely focussed on formulations with moisturising, anti-inflammatory, anti-microbial and wound healing properties. However, none of these interventions has emerged as a consistent candidate for best practice. Much less emphasis has been placed on evaluating ways to protect the radiation-damaged skin from friction and excess moisture. This mini review analyses the clinical evidence for barrier products that form a protective layer by adhering very closely to the skin folds and do not cause further trauma to the radiation-damaged skin upon removal. A database search identified only two types of barrier products that fitted these criteria and these were tested in two case series and six controlled clinical trials. Friction protection was most effective when the interventions were used from the start of treatment and continued for several weeks after completion of treatment. Soft silicone dressings (Mepilex Lite and Mepitel Film) and Cavilon No Sting Barrier Film, but not Cavilon Moisturizing Barrier Cream, decreased skin reaction severity, most likely due to differences in formulation and skin build-up properties. It seems that prophylactic use of friction protection of areas at risk could be a worthwhile addition to routine care of radiation-damaged skin

SOME OBSERVATIONS ON THE DESIGN OF NOISE BARRIERS

OpenAIRE

Arkadiusz BOCZKOWSKI

2013-01-01

The issue connected with effectiveness of noise barriers has been the subject of numerous considerations among acousticians. On the one hand, noise barriers are still the most popular and the most frequently used protection against traffic noise, on the other hand, however, the excessive number of noise barriers and the results of research focusing on effectiveness of the existing barriers make us reflect whether it is reasonable to use them. Very often low effectiveness of noise barriers is ...

Construction and operational experiences of engineered barrier test facility for near surface disposal of LILW

International Nuclear Information System (INIS)

Park, Jin Beak; Park, Se Moon; Kim, Chang Lak

2003-01-01

Engineered barrier test facility is specially designed to demonstrate the performance of engineered barrier system for the near-surface disposal facility under the domestic environmental conditions. Comprehensive measurement systems are installed within each test cell. Long-and short-term monitoring of the multi-layered cover system can be implemented according to different rainfall scenarios with artificial rainfall system. Monitoring data on the water content, temperature, matric potential, lateral drainage and percolation of cover-layer system can be systematically managed by automatic data acquisition system. The periodic measurement data are collected and will be analyzed by a dedicated database management system, and provide a basis for performance verification of the disposal cover design

Testing methodology of embedded software in digital plant protection system

International Nuclear Information System (INIS)

Seong, Ah Young; Choi, Bong Joo; Lee, Na Young; Hwang, Il Soon

2001-01-01

It is necessary to assure the reliability of software in order to digitalize RPS(Reactor Protection System). Since RPS causes fatal damage on accidental cases, it is classified as Safety 1E class. Therefore we propose the effective testing methodology to assure the reliability of embedded software in the DPPS(Digital Plant Protection System). To test the embedded software effectively in DPPS, our methodology consists of two steps. The first is the re-engineering step that extracts classes from structural source program, and the second is the level of testing step which is composed of unit testing, Integration Testing and System Testing. On each testing step we test the embedded software with selected test cases after the test item identification step. If we use this testing methodology, we can test the embedded software effectively by reducing the cost and the time

Automated testing of reactor protection instrumentation made easy

International Nuclear Information System (INIS)

Iborra, A.; De Marcos, F.; Pastor, J.A.; Alvarez, B.; Jimenez, A.; Mesa, E.; Alsonso, L.; Regidor, J.J.

1997-01-01

Maintenance and testing of reactor protection systems is an important cause of unplanned reactor trips. Automated testing is the answer because it minimises test times and reduces human error. The GAMA I system, developed and implemented at Vandellos II in Spain, has the added advantage that it uses visual programming, which means that changing the software does not need specialist programming skills. (author)

A Tracer Test to Characterize Treatment of TCE in a Permeable Reactive Barrier

Science.gov (United States)

A tracer test was conducted to characterize the flow of ground water surrounding a permeable reactive barrier constructed with plant mulch (a biowall) at the OU-1 site on Altus Air Force Base, Oklahoma. This biowall is intended to intercept and treat ground water contaminated by ...

The development of surface barriers at the Hanford Site

International Nuclear Information System (INIS)

Wing, N.R.; Gee, G.W.

1994-03-01

Engineered barriers are being developed to isolate wastes disposed of near the earth's surface at the US Department of Energy's (DOE) Hanford Site near Richland, Washington. Much of the waste that would be disposed of by in-place stabilization currently is located in relatively shallow subsurface structures such as solid waste burial grounds, tanks, vaults, and cribs. Unless protected in some way, the wastes could be transported to the accessible environment via the following pathways: plant, animal, and human intrusion; water infiltration; erosion; and the exhalation of noxious gases. Permanent isolation surface barriers have been proposed to protect wastes disposed of ''in place'' from the transport pathways identified previously (Figure 1). The protective barrier consists of a variety of different materials (e.g., fine soil, sand, gravel, riprap, asphalt, etc.) placed in layers to form an above-grade mound directly over the waste zone. Surface markers are being considered for placement around the periphery of the waste sites to inform future generations of the nature and hazards of the buried wastes. In addition, throughout the protective barrier, subsurface markers could be placed to warn any inadvertent human intruders of the dangers of the buried wastes (Figure 2)

Al-based anti-corrosion and T-permeation barrier development for future DEMO blankets

International Nuclear Information System (INIS)

Krauss, W.; Konys, J.; Holstein, N.; Zimmermann, H.

2011-01-01

In the Helium-Cooled-Liquid-Lead (HCLL) design of Test-Blanket-Modules (TBM's) for a future fusion power plant Pb-15.7Li is used as liquid breeder which is in direct contact with the structure material, e.g. EUROFER steel. Compatibility testing showed that high corrosion attack appears and that the dissolved steel components form precipitates with a high risk of system blockages. A reliable operation needs coatings as corrosion barriers. The earlier developed Hot-Dip Aluminisation (HDA) process has shown that Al-based scales can act as anti-corrosion as well as T-permeation barriers. Meanwhile two advanced electro-chemically based processes for deposition of Al-scales were successfully developed. The first (ECA = Electro-Chemical Al-deposition) is working with an organic electrolyte and the second one (ECX = Electro-Chemical-X-metal-deposition) is based on ionic liquids. Coatings in the μm-range were deposited homogeneously with exact controllable thicknesses. Metallurgical investigations showed the successful generation of protective scales and compatibility testing demonstrated the barrier function.

Al-based anti-corrosion and T-permeation barrier development for future DEMO blankets

Energy Technology Data Exchange (ETDEWEB)

Krauss, W., E-mail: wolfgang.krauss@kit.edu [Karlsruhe Institute of Technology, Hermann von Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Konys, J.; Holstein, N.; Zimmermann, H. [Karlsruhe Institute of Technology, Hermann von Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2011-10-01

In the Helium-Cooled-Liquid-Lead (HCLL) design of Test-Blanket-Modules (TBM's) for a future fusion power plant Pb-15.7Li is used as liquid breeder which is in direct contact with the structure material, e.g. EUROFER steel. Compatibility testing showed that high corrosion attack appears and that the dissolved steel components form precipitates with a high risk of system blockages. A reliable operation needs coatings as corrosion barriers. The earlier developed Hot-Dip Aluminisation (HDA) process has shown that Al-based scales can act as anti-corrosion as well as T-permeation barriers. Meanwhile two advanced electro-chemically based processes for deposition of Al-scales were successfully developed. The first (ECA = Electro-Chemical Al-deposition) is working with an organic electrolyte and the second one (ECX = Electro-Chemical-X-metal-deposition) is based on ionic liquids. Coatings in the {mu}m-range were deposited homogeneously with exact controllable thicknesses. Metallurgical investigations showed the successful generation of protective scales and compatibility testing demonstrated the barrier function.

105-KE Basin isolation barrier leak rate test analytical development. Revision 1

International Nuclear Information System (INIS)

Irwin, J.J.

1995-01-01

This document provides an analytical development in support of the proposed leak rate test of the 105-KE Basin. The analytical basis upon which the K-basin leak test results will be used to determine the basin leakage rates is developed in this report. The leakage of the K-Basin isolation barriers under postulated accident conditions will be determined from the test results. There are two fundamental flow regimes that may exist in the postulated K-Basin leakage: viscous laminar and turbulent flow. An analytical development is presented for each flow regime. The basic geometry and nomenclature of the postulated leak paths are denoted

Thermal Conductivity Analysis and Lifetime Testing of Suspension Plasma-Sprayed Thermal Barrier Coatings

Directory of Open Access Journals (Sweden)

Nicholas Curry

2014-08-01

Full Text Available Suspension plasma spraying (SPS has become an interesting method for the production of thermal barrier coatings for gas turbine components. The development of the SPS process has led to structures with segmented vertical cracks or column-like structures that can imitate strain-tolerant air plasma spraying (APS or electron beam physical vapor deposition (EB-PVD coatings. Additionally, SPS coatings can have lower thermal conductivity than EB-PVD coatings, while also being easier to produce. The combination of similar or improved properties with a potential for lower production costs makes SPS of great interest to the gas turbine industry. This study compares a number of SPS thermal barrier coatings (TBCs with vertical cracks or column-like structures with the reference of segmented APS coatings. The primary focus has been on lifetime testing of these new coating systems. Samples were tested in thermo-cyclic fatigue at temperatures of 1100 °C for 1 h cycles. Additional testing was performed to assess thermal shock performance and erosion resistance. Thermal conductivity was also assessed for samples in their as-sprayed state, and the microstructures were investigated using SEM.

Scaling community land protection in the face of large-land ...

International Development Research Centre (IDRC) Digital Library (Canada)

A mix of research methods will examine the institutional and policy barriers to securing tenure, how land registration processes and community-level rules can protect ... It will also develop and test approaches to enhancing their participation in decision-making over communal land and during negotiations with investors.

Radiation protection. Clothing for protection against radioactive contamination. Design, selection, testing and use

International Nuclear Information System (INIS)

1987-09-01

The present Standard gives the characteristics of clothing protecting the wearer against radioactive contamination brought about by contact with liquid or solid substances or by atmospheric pollutants, such as solid particles, mist, gases or vapours. The Standard applies to two types of clothing: firstly, ventilated-pressurized garments; secondly, unventilated-unpressurized garments. A test method according to which any new type of garment can be assigned a protection factor that makes it easier for the user to make a choice is described. The report also gives methods for measuring leak-tightness and air supply flow rates of ventilated-pressurized garments. For guidance purposes only, recommendations for choosing protective clothing are given. 5 figs, 2 tabs [fr

Test methods for protective footwear against AP mine blast

NARCIS (Netherlands)

Cronin, D.S.; Williams, K.; Bass, C.R.; Magnan, P.; Dosquet, F.; Bergeron, D.M.; Bree, J.L.M.J. van

2003-01-01

The testing and development of protective footwear for anti-personnel landmine blast threats is of great importance to civilian and military deminers, and peacekeepers. This study will review the wide range of test methods that have been developed by NATO countries to test footwear against the

Field tests with vertical perforated drain pipes used for beach protection at Southern Holmsland Barrier on the Danish North Sea Coast (half year report)

DEFF Research Database (Denmark)

Burcharth, Hans F.; Fredsøe, Jørgen

In accordance with the agreement of 18 August 2004 between Skagen Innovation Center (SIC) and the Danish Governmental Coastal Authority (KDI) a field test with the purpose of demonstrating the efficiency of the SIC vertical drain method as a mean for coastal protecting was initiated in a meeting 24...

Examining physiotherapist use of structured aerobic exercise testing to decrease barriers to aerobic exercise.

Science.gov (United States)

Foster B Sc, Evan; Fraser, Julia E; Inness PhD, Elizabeth L; Munce, Sarah; Biasin, Louis; Poon, Vivien; Bayley, Mark

2018-04-03

To determine the frequency of physiotherapist-administered aerobic exercise testing/training, the proportion of physiotherapists who administer this testing/training, and the barriers that currently exist across different practice environments. A secondary objective is to identify the learning needs of physiotherapists for the development of an education curriculum in aerobic exercise testing and training with electrocardiograph (ECG) administration and interpretation. National, cross-sectional survey. Registered physiotherapists practicing in Canada. Out of 137 participants, most (75%) physiotherapists prescribed aerobic exercise on a regular basis (weekly); however, 65% had never conducted an aerobic exercise test. There were no significant differences in frequency of aerobic exercise testing across different practice environments or across years of physiotherapy experience. Physiotherapists perceived the main barriers to aerobic exercise testing as being a lack of equipment/space (78%), time (65%), and knowledge (56%). Although most (82%) were uncomfortable administering 12-lead ECG-monitored aerobic exercise tests, 60% stated they would be interested in learning more about ECG interpretation. This study found that physiotherapists are regularly implementing aerobic exercise. This exercise was infrequently guided by formal aerobic exercise testing, which could increase access to safe and effective exercise within the optimal aerobic training zone. As well, this could facilitate training in patients with cardiovascular diagnoses that require additional testing for medical clearance. Increased ECG training and access to equipment for physiotherapists may augment pre-screening aerobic exercise testing. This training should include learning the key arrhythmias for aerobic exercise test termination as defined by the American College of Sports Medicine.

Ranking protective coatings: Laboratory vs. field experience

Science.gov (United States)

Conner, Jeffrey A.; Connor, William B.

1994-12-01

Environmentally protective coatings are used on a wide range of gas turbine components for survival in the harsh operating conditions of engines. A host of coatings are commercially available to protect hot-section components, ranging from simple aluminides to designer metallic overlays and ceramic thermal barrier coatings. A variety of coating-application processes are available, and they range from simple pack cementation processing to complex physical vapor deposition, which requires multimillion dollar facilities. Detailed databases are available for most coatings and coating/process combinations for a range of laboratory tests. Still, the analysis of components actually used in engines often yields surprises when compared against predicted coating behavior from laboratory testing. This paper highlights recent work to develop new laboratory tests that better simulate engine environments. Comparison of in-flight coating performance as well as industrial and factory engine testing on a range of hardware is presented along with laboratory predictions from standard testing and from recently developed cyclic burner-rig testing.

Structural analysis of closure cap barriers: A pre-test study for the Bentonite Mat Demonstration Project

International Nuclear Information System (INIS)

Gong, Chung; Pelfrey, J.R.

1993-01-01

The Bentonite Mat Demonstration Project (BMDP) is a field demonstration study to determine the construction/installation requirements, permeability, and subsidence performance characteristics of a composite barrier. The composite barrier will consist of on-site sandy-clay blanketed by a bentonite mat and a flexible High Density Polyethylene (HDPE) liner (also called flexible membrane liner). Construction of one control test pad and three bentonite test pads are planned. The control test pad will be used to establish baseline data. Underneath the composite clay cap is a four feet thick loose sand layer in which cavities will be created by evacuation of sand. The present work provides a mathematical model for the BMDP. The mathematical model will be used to simulate the mechanical and structural responses of the composite clay cap during the testing processes. Based upon engineering experience and technical references, a set of nominal soil parameters have been selected

The Barriers to Achieve Financial Protection in Iranian Health System: A Qualitative Study in a Developing Country.

Science.gov (United States)

Naghdi, Seyran; Moradi, Tayebeh; Tavangar, Fateh; Bahrami, Giti; Shahboulaghi, Mohammadi; Ghiasvand, Hesam

2017-09-01

The move to universal health coverage and consequently health promotion is influenced by political, socio-economic and other contextual factors in a country. Iran, as a developing country with an upper-middle national income, has developed policies to achieve universal health coverage through financial protection. This study aims to investigate barriers to develop financial protection as a requirement to achieve universal health coverage. This qualitative study was conducted using 20 in-depth interviews with experts in social welfare, health insurance and financing. The framework analysis method was used to analyze the data. The results have been categorized in three major themes that were extracted from ten sub-themes. The major themes included the political, social and economic context of the country, the context and structure of healthcare system and dimensions of UHC. Achieving financial protection as a long-term objective should be considered as a priority among Iranian policy makers that requires an inter-sectoral collaboration with a defined in-charge body. Health policy makers in Iran should develop a more comprehensive benefits package for diseases and health conditions with catastrophic consequences. They also should develop a plan to cover the poor people.

Engineered Barrier System Thermal-Hydraulic-Chemical Column Test Report

International Nuclear Information System (INIS)

W.E. Lowry

2001-01-01

The Engineered Barrier System (EBS) Thermal-Hydraulic-Chemical (THC) Column Tests provide data needed for model validation. The EBS Degradation, Flow, and Transport Process Modeling Report (PMR) will be based on supporting models for in-drift THC coupled processes, and the in-drift physical and chemical environment. These models describe the complex chemical interaction of EBS materials, including granular materials, with the thermal and hydrologic conditions that will be present in the repository emplacement drifts. Of particular interest are the coupled processes that result in mineral and salt dissolution/precipitation in the EBS environment. Test data are needed for thermal, hydrologic, and geochemical model validation and to support selection of introduced materials (CRWMS M and O 1999c). These column tests evaluated granular crushed tuff as potential invert ballast or backfill material, under accelerated thermal and hydrologic environments. The objectives of the THC column testing are to: (1) Characterize THC coupled processes that could affect performance of EBS components, particularly the magnitude of permeability reduction (increases or decreases), the nature of minerals produced, and chemical fractionation (i.e., concentrative separation of salts and minerals due to boiling-point elevation). (2) Generate data for validating THC predictive models that will support the EBS Degradation, Flow, and Transport PMR, Rev. 01

Barriers to Pap Smear Test for the Second Time in Women Referring to Health Care Centers in the South of Tehran: A Qualitative Approach

Directory of Open Access Journals (Sweden)

Laleh Hassani

2017-10-01

Full Text Available Background: Cervical cancer is a preventable disease with a regular screening program. Many studies have reported a large number of barriers that women had for the first time, but this study decided to find other barriers for the second time pap smear. Methods: In this qualitative research, data were gathered through in-depth interviews and expressed through conventional content analysis in the form of constant comparison. The participants were 15 women with family profile at 30 health care centers who lived in the south of Tehran and had done Pap smear for one time but didn’t do it for the second time. Results: Three main themes emerged from the analysis of the interviews: negative experiences of the first Pap test were as follows: results of the first time test, readiness for performing the test, getting the test itself, and the site of the first Pap test. Personal barriers to getting the second Pap test were: inattention to time, physical barriers to the second Pap test, and inhibitory beliefs. Perceived social barriers to getting the second Pap test with two sub-themes included social supports and abstract norms. Conclusion: This study provided other barriers about Pap smear including lack of the spouse’s support, the role of health care providers and physicians in screening program for early diagnosis in women.

Active Protection of an MgB2 Test Coil

Science.gov (United States)

Park, Dong Keun; Hahn, Seungyong; Bascuñán, Juan; Iwasa, Yukikazu

2011-01-01

This paper presents results of a study, experimental and computational, of a detect-and-activate-the-heater protection technique applied to a magnesium diboride (MgB2) test coil operated in semi-persistent mode. The test coil with a winding ID of 25 cm and wound with ~500-m long reacted MgB2 wire was operated at 4.2 K immersed in a bath of liquid helium. In this active technique, upon the initiation of a “hot spot” of a length ~10 cm, induced by a “quench heater,” a “protection heater” (PH) of ~600-cm long planted within the test coil is activated. The normal zone created by the PH is large enough to absorb the test coil’s entire initial stored energy and still keeps the peak temperature within the winding below ~260 K. PMID:22081754

Engineered Barrier System - Manufacturing, Testing and Quality Assurance. Report from a Workshop

International Nuclear Information System (INIS)

2004-06-01

As part of preparations for review of future license applications, the Swedish Nuclear Power Inspectorate (SKI) organised a workshop on the engineered barrier system for the KBS-3 concept, with the focus on manufacturing, testing and quality assurance. The main purpose of the workshop was to identify critical issues in the demonstration of how long-term safety requirements could be fulfilled for the engineered barriers. The workshop included presentations related to engineered barrier manufacturing and testing held by external experts, and working group sessions to prepare questions to the Swedish Nuclear Fuel and Waste Management Co. (SKB). SKB presentations were followed by an informal questioning and discussion with SKB representatives. This report includes a presentation of the questions posed by the working groups, SKB's replies to these questions as well as a summary of the working group discussions. The conclusions and viewpoints presented in this report are those of one or several workshop participants. During the workshop many issues regarding manufacturing, testing and quality assurance of the engineered barriers were discussed. The central themes in the questions and discussions are summarised as follows: There is a need to specify how the functional requirements for the buffer and backfill will be achieved in practise. Issues of particular interest are material selection, compaction density, initial water content and manufacturing methods for bentonite blocks. A major problem that must be addressed is the long period required to obtain relevant results from large-scale testing. The uncertainties relating to the wetting and subsequent swelling processes of the bentonite buffer have implications for analysis of the canister. It is necessary to know now non-uniform the bentonite swelling pressure could be in a worst case pressure differential, in order to evaluate the sufficiency of 'as tested' canister performance. Regarding the copper shell of the

Automated reactor protection testing saves time and avoids errors

International Nuclear Information System (INIS)

Raimondo, E.

1990-01-01

When the Pressurized Water Reactor units in the French 900MWe series were designed, the instrumentation and control systems were equipped for manual periodic testing. Manual reactor protection system testing has since been successfully replaced by an automatic system, which is also applicable to other instrumentation testing. A study on the complete automation of process instrumentation testing has been carried out. (author)

Investigations of thermal barrier coatings of turbine parts using gas flame heating

Science.gov (United States)

Lepeshkin, A. R.; Bichkov, N. G.; Ilinskaja, O. I.; Nazarov, V. V.

2017-09-01

The development of methods for the calculated and experimental investigations thermal barrier coatings and thermal state of gas-turbine engine parts with a thermal barrier coatings is actual work. The gas flame heating was demonstrated to be effectively used during investigations of a thermal ceramic barrier coatings and thermal state of such gas-turbine engine parts with a TBC as the cooled turbine blades and vanes and combustion liner components. The gas-flame heating is considered to be preferable when investigating the gas-turbine engine parts with a TBC in the special cases when both the convective and radiant components of thermal flow are of great importance. The small-size rig with gas-flame flow made it possible to conduct the comparison investigations with the purpose of evaluating the efficiency of thermal protection of the ceramic deposited thermal barrier coatings on APS and EB techniques. The developed design-experiment method was introduced in bench tests of turbine blades and combustion liner components of gas turbine engines.

Coastal Inlets Research Program. Barrier Island Migration Over a Consolidating Substrate

Science.gov (United States)

2009-09-01

the toe of the dune to the high water line) for full development of eolian transport. However, the original Shore Protection Manual (1984...tested. Barrier islands overlying a compressible substrate are more likely to have reduced dune elevations due to consolidation, incur overall...migra- tion when the dune reaches a critical elevation with respect to the prev- alent storm conditions. Initial large-scale infusion of sand from an

Project W-314 Polyurea Special Protective Coating (SPC) Test Plan Chemical Compatibility and Physical Characteristics Testing

International Nuclear Information System (INIS)

MAUSER, R.W.

2001-01-01

This Test Plan outlines the testing to be done on the Special Protective Coating (SPC) Polyurea which includes: Tank Waste Compatibility, Decontamination Factor Testing, and Adhesion Strength Testing after a sample has been exposed to Radiation

Implementing solutions to barriers to on-site HIV testing in substance abuse treatment: a tale of three facilities.

Science.gov (United States)

Hood, Kristina B; Robertson, Angela A; Baird-Thomas, Connie

2015-04-01

Due to the scarcity of resources for implementing rapid on-site HIV testing, many substance abuse treatment programs do not offer these services. This study sought to determine whether addressing previously identified implementation barriers to integrating on-site rapid HIV testing into the treatment admissions process would increase offer and acceptance rates. Results indicate that it is feasible to integrate rapid HIV testing into existing treatment programs for substance abusers when resources are provided. Addressing barriers such as providing start-up costs for HIV testing, staff training, addressing staffing needs to reduce competing job responsibilities, and helping treatment staff members overcome their concerns about clients' reactions to positive test results is paramount for the integration and maintenance of such programs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Migration of inorganic ions from the leachate of the Rio das Ostras landfill: a comparison of three different configurations of protective barriers.

Science.gov (United States)

Lacerda, Cláudia Virgínia; Ritter, Elisabeth; Pires, João Antônio da Costa; de Castro, José Adilson

2014-11-01

Batch tests and diffusion tests were performed to analyze the efficiency of a protective barrier in a landfill consisting of compacted soil with 10% bentonite compared to the results obtained for only compacted soil and for compacted soil covered with a 1-mm-thick HDPE geomembrane; the soil and leachate were collected from the Rio das Ostras Landfill in Rio de Janeiro, Brazil. The diffusion tests were performed for periods of 3, 10 and 60 days. After the test period, the soil pore water was analyzed and the profiles for chloride, potassium and ammonium were determined along a 6-cm soil depth. The results of the batch tests performed to define sorption parameters were used to adjust the profiles obtained in the diffusion cell experiment by applying an ion transfer model between the interstitial solution and the soil particles. The MPHMTP model (Multi Phase Heat and Mass Transfer Program), which is based upon the solution of the transport equations of the ionic contaminants, was used to solve the inverse problem of simultaneously determining the effective diffusion coefficients. The results of the experimental tests and of the model simulation confirmed that the compacted soil with 10% bentonite was moderately efficient in the retention of chloride, potassium and ammonium ions compared to the configurations of compacted soil with a geomembrane and compacted soil alone, representing a solution that is technically feasible and requires potentially lower costs for implementation in landfills. Copyright © 2014 Elsevier Ltd. All rights reserved.

Deactivation of SCR catalysts by potassium: A study of potential alkali barrier materials

DEFF Research Database (Denmark)

Olsen, Brian Kjærgaard; Kügler, Frauke; Castellino, Francesco

2017-01-01

The use of coatings in order to protect vanadia based SCR catalysts against potassium poisoning has been studied by lab- and pilot-scale experiments. Three-layer pellets, consisting of a layer ofa potential coating material situated between layers of fresh and potassium poisoned SCR catalyst, were...... the coating process. Potassium had to some extent penetrated the MgO coat, and SEM analysis revealed it to be rather thick and fragile. Despite these observations, the coating did protect the SCR catalyst against potassium poisoning to some degree, leaving promise of further optimization....... used to test the ability of the barrier layer to block the diffusion of potassium across the pellet. Of MgO, sepiolite and Hollandite manganese oxide, MgO was the most effective potassium barrier, and no potassium was detected in the MgO layer upon exposure to SCR conditions for 7 days. Two monoliths...

Preliminary test of two stump surface protectants against Fomes annosus.

Science.gov (United States)

E.E. Nelson; C.Y. Li

1980-01-01

Two materials, monolaurin (at two concentrations) and an unidentified species of the genus Streptomyces, were tested along with borax for ability to protect freshly cut stump surfaces of western hemlock (Tsuga heterophylla (Raf.) Sarg.) from colonization by Fomes annosus. Protectants were significantly (P...

Test equipment used for radiation protection type testing of aerosol filters at the National Board of Nuclear Safety and Radiation Protection (SAAS)

International Nuclear Information System (INIS)

Ullmann, W.; Przyborowski, S.

1977-01-01

Following a description of the overall design of test equipment developed in the SAAS for radiation protection type testing of aerosol filters, the most important physical and technical details concerning the preparation and measurement of test aerosols as well as the sampling procedure upstream and downstream of the filter to the tested, are comprehensively discussed. Furthermore, experiences gained during several years with different devices for mixing and diluting the aerosols are reported. (author)

Targeted liposomes for drug delivery across the blood-brain barrier

NARCIS (Netherlands)

van Rooy, I.

2011-01-01

Our brain is protected by the blood-brain barrier (BBB). This barrier is formed by specialized endothelial cells of the brain vasculature and prevents toxic substances from entering the brain. The downside of this barrier is that many drugs that have been developed to cure brain diseases cannot

Barriers to Point-of-Care Testing in India: Results from Qualitative Research across Different Settings, Users and Major Diseases

Science.gov (United States)

Engel, Nora; Ganesh, Gayatri; Patil, Mamata; Yellappa, Vijayashree; Pant Pai, Nitika; Vadnais, Caroline; Pai, Madhukar

2015-01-01

Background Successful point-of-care testing, namely ensuring the completion of the test and treat cycle in the same encounter, has immense potential to reduce diagnostic and treatment delays, and impact patient outcomes. However, having rapid tests is not enough, as many barriers may prevent their successful implementation in point-of-care testing programs. Qualitative research on diagnostic practices may help identify such barriers across different points of care in health systems. Methods In this exploratory qualitative study, we conducted 78 semi-structured interviews and 13 focus group discussions in an urban and rural area of Karnataka, India, with healthcare providers (doctors, nurses, specialists, traditional healers, and informal providers), patients, community health workers, test manufacturers, laboratory technicians, program managers and policy-makers. Participants were purposively sampled to represent settings of hospitals, peripheral labs, clinics, communities and homes, in both the public and private sectors. Results In the Indian context, the onus is on the patient to ensure successful point-of-care testing across homes, clinics, labs and hospitals, amidst uncoordinated providers with divergent and often competing practices, in settings lacking material, money and human resources. We identified three overarching themes affecting point-of-care testing: the main theme is ‘relationships’ among providers and between providers and patients, influenced by the cross-cutting theme of ‘infrastructure’. Challenges with both result in ‘modified practices’ often favouring empirical (symptomatic) treatment over treatment guided by testing. Conclusions Even if tests can be conducted on the spot and infrastructure challenges have been resolved, relationships among providers and between patients and providers are crucial for successful point-of-care testing. Furthermore, these barriers do not act in isolation, but are interlinked and need to be examined

Barriers to Point-of-Care Testing in India: Results from Qualitative Research across Different Settings, Users and Major Diseases.

Directory of Open Access Journals (Sweden)

Nora Engel

Full Text Available Successful point-of-care testing, namely ensuring the completion of the test and treat cycle in the same encounter, has immense potential to reduce diagnostic and treatment delays, and impact patient outcomes. However, having rapid tests is not enough, as many barriers may prevent their successful implementation in point-of-care testing programs. Qualitative research on diagnostic practices may help identify such barriers across different points of care in health systems.In this exploratory qualitative study, we conducted 78 semi-structured interviews and 13 focus group discussions in an urban and rural area of Karnataka, India, with healthcare providers (doctors, nurses, specialists, traditional healers, and informal providers, patients, community health workers, test manufacturers, laboratory technicians, program managers and policy-makers. Participants were purposively sampled to represent settings of hospitals, peripheral labs, clinics, communities and homes, in both the public and private sectors.In the Indian context, the onus is on the patient to ensure successful point-of-care testing across homes, clinics, labs and hospitals, amidst uncoordinated providers with divergent and often competing practices, in settings lacking material, money and human resources. We identified three overarching themes affecting point-of-care testing: the main theme is 'relationships' among providers and between providers and patients, influenced by the cross-cutting theme of 'infrastructure'. Challenges with both result in 'modified practices' often favouring empirical (symptomatic treatment over treatment guided by testing.Even if tests can be conducted on the spot and infrastructure challenges have been resolved, relationships among providers and between patients and providers are crucial for successful point-of-care testing. Furthermore, these barriers do not act in isolation, but are interlinked and need to be examined as such. Also, a test alone has only

Routine testing on protective and safety systems and components

International Nuclear Information System (INIS)

Rysy, W.

1977-01-01

1) In-process inspection, tests during commissioning. 2) Tests during reactor operation. 2.1) Reactor protection system, for example: continuous auto-testing by a dynamic system, check of the output signals; 2.2) safety features: selected examples: functional tests on the ECCS, trial operation of the emergency diesels. 3) Tests during refuelling phase. 3.1) Containment: Leakage rate tests, leak testing; 3.2) coolant system: selected examples: inservice inspections of the pressure vessel, eddy current testing of the steam generator, functional tests of safety valves. (orig./HP) [de

CMHC [Canada Mortgage and Housing Corporation] research project: Testing of air barrier construction details 2

Energy Technology Data Exchange (ETDEWEB)

1993-03-31

Air leakage control through the building envelope of wood framed houses is more important than ever. This is because owners expect better temperature control, higher indoor humidity in winter, low energy consumption and building durability. The leakage of air is controlled by the air barrier system. There are several new technologies to construct an air barrier system for the building envelope. These are the Poly Approach, the Air Drywall Approach (ADA) and the EASE system. The development of these systems was undertaken primarily by the building community without significant research and development. While it is believed that these methods improve airtightness it is not known if the improvement is marginal or significant. A study was conducted to determine actual performace of several different types of construction details for each of the different approaches. Each of these details was designed and constructed using one of the air barrier methods and tested in the laboratory. The test details included sill plate, the partition wall, the stair stringer, the electrical outlets, the bathtub detail, the plumbing stack detail, the metal chimney detail, the bathroom fan detail and the EASE wall system. The test results revealed that the Poly, ADA and EASE approaches reduce air leakage by a factor of six, if applied with a modest degree of workmanship. Further, certain Poly details are to be reconsidered because they lack adequate support against design wind load pressures. 37 figs., 12 tabs.

Assessment of the knowledge of United Arab Emirates dentists of Child Maltreatment, protection and safeguarding.

Science.gov (United States)

Al Hajeri, H; Al Halabi, M; Kowash, M; Khamis, A H; Welbury, R; Hussein, I

2018-06-01

Child safeguarding is society's responsibility. Dentists are uniquely positioned to recognise Child Abuse and Neglect (CAN) in dental practice and the wider society. The United Arab Emirates (UAE) introduced a child protection law in 2016. We aimed to assess the awareness of UAE dentists of child maltreatment, protection and safeguarding. Study Design A cross-sectional survey. We surveyed 381 UAE dentists about the knowledge and practice of CAN and safeguarding issues using a self-administered anonymous questionnaire. Statistical analysis was carried out using Chi-square, t-test, ANOVA and Pearson's correlation test and statistical significance was set as p knowledgeable about diagnosing CAN. Paediatric dentists attended more CAN-related postgraduate training (pprotection guidelines. Dentists barriers to child protection reporting were; fear of family violence (59.6%, n=227), lack of knowledge of referral process (60.2%, n=228) and lack of diagnosis certainty (54.9%, n=206). UAE dentists qualified in Western and Asian countries had fewer barriers for child protection reporting (p=0.022) than the Arab and Gulf Cooperation Council qualified dentists. A large minority of UAE dentists suspected CAN. Factors influencing child protection reporting were identified. Dentists' gender, specialty, and country of qualification affected their knowledge of CAN and practice of safeguarding. Child protection training is recommended.

The principles for creation of fire-prevention forest belts with barriers of deciduous species for protection from crown fires

Directory of Open Access Journals (Sweden)

S. N. Sannikov

2017-10-01

Full Text Available The article discuss one of the priority security problems in Russia, which is elaboration of the strategic system of the forest and society safeguards from catastrophic forest crown fires in connection with rapid climate warming. It is postulated, that a most effective and reliable barrier for the dispersal of the intensive crown fire in a coniferous forest massive can be a sufficiently wide strip of deciduous tree species – «deciduous forest barrier», which has phytomass capable of absorbing crown fire energy and transforming them to surface fire, which may be extinguished by technical means. The actuality of the natural study of the transition parameters from the crown fire to surface fire has been noted, depending on climate, fire intensity and the deciduous barrier structure. The results of the quantitative natural investigation of the consequences of catastrophic crown fires of 2004 in the island pine forests of forest-steppe zone in Kurgan Oblast, which passed through the belt of 50–70 year-old birch stands of middle density, has been cited and formalized mathematically. It has been shown, that 150 m width of deciduous forest barrier is necessary as a minimum for the reliable transition of the high intensive front crown fire to surface fire in the forest-steppe conditions of the Western Siberia, but this width reduces with a decreasing heating effect. It has been proposed to create the complex fire-prevention forest belts of different construction for the protection of forests, industrial objects and settlements. Besides a basic deciduous barrier, their structure should include technologically necessary buffer zones and zones for the localization and extinguishing surface fire, which stop a crown fire. It has been recommended to use natural regeneration of deciduous tree species, as a most effective and non-deficient method for the creation of deciduous forest barriers in the predominant forest types, except the lichen pine forests

(--Epicatechin protects the intestinal barrier from high fat diet-induced permeabilization: Implications for steatosis and insulin resistance

Directory of Open Access Journals (Sweden)

Eleonora Cremonini

2018-04-01

Full Text Available Increased permeability of the intestinal barrier is proposed as an underlying factor for obesity-associated pathologies. Consumption of high fat diets (HFD is associated with increased intestinal permeabilization and increased paracellular transport of endotoxins which can promote steatosis and insulin resistance. This study investigated whether dietary (--epicatechin (EC supplementation can protect the intestinal barrier against HFD-induced permeabilization and endotoxemia, and mitigate liver damage and insulin resistance. Mechanisms leading to loss of integrity and function of the tight junction (TJ were characterized. Consumption of a HFD for 15 weeks caused obesity, steatosis, and insulin resistance in male C57BL/6J mice. This was associated with increased intestinal permeability, decreased expression of ileal TJ proteins, and endotoxemia. Supplementation with EC (2–20 mg/kg body weight mitigated all these adverse effects. EC acted modulating cell signals and the gut hormone GLP-2, which are central to the regulation of intestinal permeability. Thus, EC prevented HFD-induced ileum NOX1/NOX4 upregulation, protein oxidation, and the activation of the redox-sensitive NF-κB and ERK1/2 pathways. Supporting NADPH oxidase as a target of EC actions, in Caco-2 cells EC and apocynin inhibited tumor necrosis alpha (TNFα-induced NOX1/NOX4 overexpression, protein oxidation and monolayer permeabilization. Together, our findings demonstrate protective effects of EC against HFD-induced increased intestinal permeability and endotoxemia. This can in part underlie EC capacity to prevent steatosis and insulin resistance occurring as a consequence of HFD consumption. Keywords: Intestinal permeability, (--Epicatechin, Steatosis, Insulin resistance, Endotoxemia, NADPH oxidase

Tests of microprocessor-based relay protection devices: Problems and solutions

Directory of Open Access Journals (Sweden)

Gurevich Vladimir

2009-01-01

Full Text Available Usually, the operational condition of relay protection devices is checked with specific settings used for the relay operation in a certain network point. In the author's opinion in order to verify the proper operation of complex multifunctional microprocessor-based protection devices (MPD at their inspection, start-up after repairs or during periodic tests there is no need to use the actual settings at which the relay is to be operated in a certain network's point. It should be tested for proper operation at several of its most critical preset characteristic points as well as in several preset characteristics constituting its most complicated (combined operation modes, including the dynamic operation modes with preset transition processes specific for standard power networks (not necessarily for a specific point. The proposed set of actions for the unification of software platforms of the modern, microprocessor-based relay protection test systems will enable examination of modern MPD in an absolutely new way. .

Multi-Barrier Protection of Drinking Water Systems in Ontario: A Comparison of First Nation and Non-First Nation Communities

Directory of Open Access Journals (Sweden)

Budhendra Singh

2012-11-01

Full Text Available In some way or another, all levels of government in Canada and First Nations share responsibility to implement multi-barrier protection of drinking water. The goal is to protect water from source to tap to minimize risk so that people have access to adequate and safe drinking water. The federal government has committed to assist First Nations achieve comparable levels of service standards available to non-First Nation communities. However, several recent reports on the status of drinking water services standards in First Nations indicate that people in these communities often experience greater health risks than those living off reserves. Using the federal drinking water risk evaluation guidelines, the capacities of First Nations and non-First Nations in Ontario to implement multi-barrier protection of their drinking water systems are compared. The Risk Level Evaluation Guidelines for Water and Wastewater Treatment in First Nation Communities rank drinking water systems as low, medium, or high risk based on information about source water, system design, system operation, reporting, and operator expertise. The risk evaluation scores for First Nations drinking water systems were obtained from Aboriginal Affairs and Northern Development Canada. A survey based on the federal Risk Level Evaluation Guidelines was sent to non-First Nation communities throughout Ontario with 54 communities responding. The capacity among First Nations was variable throughout the province, whereas all of the municipalities were in the low risk category, even small and northern non-First Nation community water systems. It is clear that the financial and technological capacity issues should be addressed regardless of the legislative and regulatory regime that is established. The current governance and management structure does not appear to be significantly reducing the gap in service standards despite financial investment. Exploring social or other underlying determinants

miR-98 and let-7g* protect the blood-brain barrier under neuroinflammatory conditions.

Science.gov (United States)

Rom, Slava; Dykstra, Holly; Zuluaga-Ramirez, Viviana; Reichenbach, Nancy L; Persidsky, Yuri

2015-12-01

Pathologic conditions in the central nervous system, regardless of the underlying injury mechanism, show a certain level of blood-brain barrier (BBB) impairment. Endothelial dysfunction is the earliest event in the initiation of vascular damage caused by inflammation due to stroke, atherosclerosis, trauma, or brain infections. Recently, microRNAs (miRNAs) have emerged as a class of gene expression regulators. The relationship between neuroinflammation and miRNA expression in brain endothelium remains unexplored. Previously, we showed the BBB-protective and anti-inflammatory effects of glycogen synthase kinase (GSK) 3β inhibition in brain endothelium in in vitro and in vivo models of neuroinflammation. Using microarray screening, we identified miRNAs induced in primary human brain microvascular endothelial cells after exposure to the pro-inflammatory cytokine, tumor necrosis factor-α, with/out GSK3β inhibition. Among the highly modified miRNAs, let-7 and miR-98 were predicted to target the inflammatory molecules, CCL2 and CCL5. Overexpression of let-7 and miR-98 in vitro and in vivo resulted in reduced leukocyte adhesion to and migration across endothelium, diminished expression of pro-inflammatory cytokines, and increased BBB tightness, attenuating barrier 'leakiness' in neuroinflammation conditions. For the first time, we showed that miRNAs could be used as a therapeutic tool to prevent the BBB dysfunction in neuroinflammation.

Technical Barriers, Licenses and Tariffs as Means of Limiting Market Access

DEFF Research Database (Denmark)

Schröder, Philipp J.H.; Jørgensen, Jan Guldager

2006-01-01

Technical barriers (standards), import licenses and tariffs may be deployed as means of limiting the market access of foreign firms. The present paper examines these measures in a setting of monopolistic competition. We find that, if protection focuses predominantly on the number of foreign firms...... accessing the domestic market, a technical barrier (an import license) may dominate a tariff (tariff and a tech- nical barrier) in terms of consumer welfare, even when tariff revenues are fully redistributed. However, if protection pays su±cient focus on limiting the total import volume, then tariffs...

Safe and secure South Africa. Vehicle landmine protection validation testing

CSIR Research Space (South Africa)

Reinecke, JD

2008-11-01

Full Text Available The objective of this paper is to provide an overview of vehicle landmine protection validation testing in South Africa. A short history of validation test standards is given, followed by a summary of current open test standards in general use...

The Automatic Test Features of the IDiPS Reactor Protection System

International Nuclear Information System (INIS)

Hur, Seop; Kim, Dong-Hoon; Hwang, In-Koo; Lee, Cheol-Kwon; Lee, Dong-Young

2007-01-01

The reactor protection system (RPS) is designed to minimize a propagation of abnormal or accident conditions of nuclear power plants. A digital RPS (Integrated Digital Protection System (IDiPS) RPS) is being developed in the Korea Nuclear Instrumentation and Control System (KNICS) R and D project. To make good use of the advantages of the digital technology, it is necessary to improve the reliability and availability of a system through automatic test features including an on-line testing, a self-diagnostics, an auto calibration, etc. This paper summarizes the system test strategy and the automatic test features of the IDiPS RPS

Development of a Midscale Test for Flame Resistant Protection

Science.gov (United States)

2016-08-01

Evaluation of Flame Resistant Clothing for Protection against Fire Simulations Using an Instrumented Manikin, which provides both radiant and convective heat...TEST METHODS FIRE RESISTANT MATERIALS TORCHES SIMULATION TEST EQUIPMENT FLAME RESISTANT CLOTHING PERFORMANCE(ENGINEERING... fabric during a fire , and even after the fire has been extinguished. The best known full scale transmitted heat flux test is the "ASTM F1930

Information barriers and authentication

International Nuclear Information System (INIS)

MacArthur, D.W.; Wolford, J.K.

2001-01-01

Acceptance of nuclear materials into a monitoring regime is complicated if the materials are in classified shapes or have classified composition. An attribute measurement system with an information barrier can be emplo,yed to generate an unclassified display from classified measurements. This information barrier must meet two criteria: (1) classified information cannot be released to the monitoring party, and (2) the monitoring party must be convinced that the unclassified output accurately represents the classified input. Criterion 1 is critical to the host country to protect the classified information. Criterion 2 is critical to the monitoring party and is often termed the 'authentication problem.' Thus, the necessity for authentication of a measurement system with an information barrier stems directly from the description of a useful information barrier. Authentication issues must be continually addressed during the entire development lifecycle of the measurement system as opposed to being applied only after the system is built.

CMHC research project: Testing of air barriers construction details: Report

Energy Technology Data Exchange (ETDEWEB)

1991-01-01

This project was conducted to quantify the air leakage characteristics of the header joist, the electric outlets, and the window openings in wood-frame walls. The study evaluated the sealed internal membrane method, where polyethylene sheet and sealant provide the air barrier; the external air barrier method, which uses a continuous vapour permeable membrane (spun-bonded olefin film), sandwiched between two layers of external wall sheathing; and the airtight drywall method, where the interior gypsum board finish, together with framing materials and gaskets, are used as the air barrier. In addition, the traditional approach to wood-frame wall construction, where no special attention is given to achieving a continuous air barrier, was evaluated for comparison.

Some scenarios of degradation of concrete structures that are used as protective barriers in nuclear power industry

International Nuclear Information System (INIS)

Vasil'chenko, V.N.; Zhigalov, Ya.A.; Sandul, G.A.; Nosovskij, A.V.

2013-01-01

The articles discusses kinetics of physical and chemical processes of destruction of the material for reinforced concrete containers that are used as protective (safety) barriers in the nuclear power industry. Characteristics of constructive concrete materials were analyzed and generalized, including those for manufacturing of RAW containers. Some chemical reactions and mechanisms are considered that have an influence on the strength properties of the containers material. Kinetics of the degradation processes in the concrete of RAW containers was studied and the analysis was made on concentration dynamics of the local destruction centers in the concrete due to influence of the considered physical and chemical processes during the operation.

Prototype Hanford Surface Barrier: Design basis document

International Nuclear Information System (INIS)

Myers, D.R.; Duranceau, D.A.

1994-11-01

The Hanford Site Surface Barrier Development Program (BDP) was organized in 1985 to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site and other arid sites. This document provides the basis of the prototype barrier. Engineers and scientists have momentarily frozen evolving barrier designs and incorporated the latest findings from BDP tasks. The design and construction of the prototype barrier has required that all of the various components of the barrier be brought together into an integrated system. This integration is particularly important because some of the components of the protective barreir have been developed independently of other barreir components. This document serves as the baseline by which future modifications or other barrier designs can be compared. Also, this document contains the minutes of meeting convened during the definitive design process in which critical decisions affecting the prototype barrier's design were made and the construction drawings

[Protective effect of Saccharomyces boulardii against intestinal mucosal barrier injury in rats with nonalcoholic fatty liver disease].

Science.gov (United States)

Liu, Y T; Li, Y Q; Wang, Y Z

2016-12-20

Objective: To investigate the protective effect of Saccharomyces boulardii against intestinal mucosal barrier injury in rats with nonalcoholic fatty liver disease (NAFLD). Methods: A total of 36 healthy male Sprague-Dawley rats with a mean body weight of 180±20 g were randomly divided into control group, model group, and treatment group, with 12 rats in each group, after adaptive feeding for 1 week. The rats in the control group were given basic feed, and those in the model group and treatment group were given high-fat feed. After 12 weeks of feeding, the treatment group was given Saccharomyces boulardii (75×10 8 CFU/kg/d) by gavage, and those in the control group and model group were given isotonic saline by gavage. At the 20th week, blood samples were taken from the abdominal aorta to measure the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), intestinal fatty acid binding protein (IFABP), tumor necrosis factor-α (TNF-α), and endotoxins. The liver pathological changes, intestinal histopathological changes, and expression of occludin in the intestinal mucosa were observed. Fecal samples were collected to measure the changes in Escherichia coli and Bacteroides. A one-way analysis of variance and the SNK test were used for comparison between multiple groups, and the rank sum test was used as the non-parametric test. Results: Compared with the control group, the model group had significantly higher body weight, liver mass, and liver index ( P 0.05). Compared with the control group, the model group had significant increases in the levels of endotoxin, TNF-α, and IFABP ( P Saccharomyces boulardii can reduce body weight and improve hepatocyte steatosis. Saccharomyces boulardii can reduce endotoxemia in NAFLD rats and thus alleviate inflammatory response. Saccharomyces boulardii can also adjust the proportion of Escherichia coli and Bacteroides in the intestine of NAFLD rats.

Nuclear technology in materials testing and radiation protection

International Nuclear Information System (INIS)

Neider, R.

1975-01-01

A report of the 1974 activities of the laboratories for physical and measuring technical fundamentals, radiation effects and radiation protection, application of radionuclides and testing of radioactive materials of the Bundesanstalt fuer Materialpruefung (BAM) is given. (RW/LH) [de

The Tritiated Water Skin Barrier Integrity Test: Considerations for Acceptance Criteria with and Without 14C-Octanol.

Science.gov (United States)

Lehman, Paul A; Beatch, Kacie; Raney, Sam G; Franz, Thomas J

2017-01-01

A study was designed to assess barrier integrity simultaneously using separate compounds (probes) for polar and non-polar pathways through the skin, 3 H 2 O and 14 C-octanol, respectively; and to determine whether the two probe approach could better define barrier integrity. A 5-min dose of water containing 3 H 2 O and 14 C -octanol was applied to ex vivo human skin mounted in Franz diffusion cells. The receptor solution was sampled at 30 min, analyzed for 3 H and 14 C content, and the correlation between water and octanol absorption was determined by statistical tests suitable for non-normally distributed data. This study was conducted on skin from 37 donors with from 3 to 30 replicate skin sections per donor (a total of 426 sections). The correlation between 3 H 2 O and 14 C-octanol absorption was low (Pearson correlation coefficient = 0.3485). The 3 H 2 O absorption cutoff used in this study to select for a normal skin barrier rejected some sections in which 14 C-octanol absorption was within normal limits and accepted others in which 14 C-octanol absorption was abnormally high. The converse was true for 3 H 2 O absorption when the 14 C-octanol-based cutoff was used. The results of the 3 H 2 O test or of similar tests that primarily assess the permeability of polar pathways through the skin may not necessarily provide information relevant to the absorption of highly lipophilic compounds. Octanol, or another molecule that more closely matches the physicochemical attributes of the test compound, may characterize properties of the skin barrier that are more relevant to compounds of low water solubility.

Clusterin Seals the Ocular Surface Barrier in Mouse Dry Eye.

Science.gov (United States)

Bauskar, Aditi; Mack, Wendy J; Mauris, Jerome; Argüeso, Pablo; Heur, Martin; Nagel, Barbara A; Kolar, Grant R; Gleave, Martin E; Nakamura, Takahiro; Kinoshita, Shigeru; Moradian-Oldak, Janet; Panjwani, Noorjahan; Pflugfelder, Stephen C; Wilson, Mark R; Fini, M Elizabeth; Jeong, Shinwu

2015-01-01

Dry eye is a common disorder caused by inadequate hydration of the ocular surface that results in disruption of barrier function. The homeostatic protein clusterin (CLU) is prominent at fluid-tissue interfaces throughout the body. CLU levels are reduced at the ocular surface in human inflammatory disorders that manifest as severe dry eye, as well as in a preclinical mouse model for desiccating stress that mimics dry eye. Using this mouse model, we show here that CLU prevents and ameliorates ocular surface barrier disruption by a remarkable sealing mechanism dependent on attainment of a critical all-or-none concentration. When the CLU level drops below the critical all-or-none threshold, the barrier becomes vulnerable to desiccating stress. CLU binds selectively to the ocular surface subjected to desiccating stress in vivo, and in vitro to the galectin LGALS3, a key barrier component. Positioned in this way, CLU not only physically seals the ocular surface barrier, but it also protects the barrier cells and prevents further damage to barrier structure. These findings define a fundamentally new mechanism for ocular surface protection and suggest CLU as a biotherapeutic for dry eye.

Clusterin Seals the Ocular Surface Barrier in Mouse Dry Eye.

Directory of Open Access Journals (Sweden)

Aditi Bauskar

Full Text Available Dry eye is a common disorder caused by inadequate hydration of the ocular surface that results in disruption of barrier function. The homeostatic protein clusterin (CLU is prominent at fluid-tissue interfaces throughout the body. CLU levels are reduced at the ocular surface in human inflammatory disorders that manifest as severe dry eye, as well as in a preclinical mouse model for desiccating stress that mimics dry eye. Using this mouse model, we show here that CLU prevents and ameliorates ocular surface barrier disruption by a remarkable sealing mechanism dependent on attainment of a critical all-or-none concentration. When the CLU level drops below the critical all-or-none threshold, the barrier becomes vulnerable to desiccating stress. CLU binds selectively to the ocular surface subjected to desiccating stress in vivo, and in vitro to the galectin LGALS3, a key barrier component. Positioned in this way, CLU not only physically seals the ocular surface barrier, but it also protects the barrier cells and prevents further damage to barrier structure. These findings define a fundamentally new mechanism for ocular surface protection and suggest CLU as a biotherapeutic for dry eye.

Seismic Barrier Protection of Critical Infrastructure from Earthquakes

Science.gov (United States)

2017-05-01

We observe that such barrier structures reduce seismic wave powers by 10 – 40 dB that would otherwise reach the foundation location. Moreover, the... structure composed of opposing boreholes or trenches to mitigate seismic waves from diffracting and traveling in the vertical plane. Computational...seismic wave propagation models suggest that air or fluid filled subsurface V- shaped muffler structures are critical to the redirection and self

Design and performance evaluation of a 1000-year evapotranspiration-capillary surface barrier

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zhuanfang Fred; Strickland, Christopher E.; Link, Steven O.

2017-02-01

Surface barrier technology is used to isolate radioactive waste and to reduce or eliminate recharge water to the waste zone for 1000 years or longer. However, the design and evaluation of such a barrier is challenging because of the extremely long design life. The Prototype Hanford Barrier (PHB) was designed as a 1000-year barrier with pre-determined design and performance objectives and demonstrated in field from 1994 to present. The barrier was tested to evaluate surface-barrier design and performance at the field scale under conditions of enhanced and natural precipitation and of no vegetation. The monitoring data demonstrate that the barrier satisfied nearly all key objectives. The PHB far exceeded the Resource Conservation and Recovery Act criteria, functioned in Hanford’s semiarid climate, limited drainage to well below the 0.5 mm yr-1 performance criterion, limited runoff, and minimized erosion. Given the two-decade record of successful performance and consideration of all the processes and mechanisms that could degrade the stability and hydrology in the future, the results suggest the PHB is very likely to perform for its 1000-year design life. This conclusion is based on two assumptions: (1) the exposed subgrade receives protection against erosion and (2) institutional controls prevent inadvertent human activity at the barrier. The PHB design can serve as the base for site-specific barriers over waste sites containing underground nuclear waste, uranium mine tailings, and hazardous mine waste.

Impacts of cathodic protection on waste package performance

International Nuclear Information System (INIS)

Atkins, J.E.; Lee, J.H.; Andrews, R.W.

1996-01-01

The current design concept for a multi-barrier waste container for the potential repository at Yucca Mountain, Nevada, calls for an outer barrier of 100 mm thick corrosion-allowance material (CAM) (carbon steel) and an inner barrier of 20 mm thick corrosion-resistant material (CRM) (Alloy 825). Fulfillment of the NRC subsystem requirements (10 CFR 60.113) of substantially complete containment and controlled release of radionuclides from the engineered barrier system (EBS) will rely mostly upon the robust waste container design, among other EBS components. In the current waste container design, some degree of cathodic protection of CRM will be provided by CAM. This paper discusses a sensitivity case study for the impacts of cathodic protection of the inner barrier by the outer barrier on the performance of waste package

Diffusion chamber system for testing of collagen-based cell migration barriers for separation of ligament enthesis zones in tissue-engineered ACL constructs.

Science.gov (United States)

Hahner, J; Hoyer, M; Hillig, S; Schulze-Tanzil, G; Meyer, M; Schröpfer, M; Lohan, A; Garbe, L-A; Heinrich, G; Breier, A

2015-01-01

A temporary barrier separating scaffold zones seeded with different cell types prevents faster growing cells from overgrowing co-cultured cells within the same construct. This barrier should allow sufficient nutrient diffusion through the scaffold. The aim of this study was to test the effect of two variants of collagen-based barriers on macromolecule diffusion, viability, and the spreading efficiency of primary ligament cells on embroidered scaffolds. Two collagen barriers, a thread consisting of a twisted film tape and a sponge, were integrated into embroidered poly(lactic-co-caprolactone) and polypropylene scaffolds, which had the dimension of lapine anterior cruciate ligaments (ACL). A diffusion chamber system was designed and established to monitor nutrient diffusion using fluorescein isothiocyanate-labeled dextran of different molecular weights (20, 40, 150, 500 kDa). Vitality of primary lapine ACL cells was tested at days 7 and 14 after seeding using fluorescein diacetate and ethidium bromide staining. Cell spreading on the scaffold surface was measured using histomorphometry. Nuclei staining of the cross-sectioned scaffolds revealed the penetration of ligament cells through both barrier types. The diffusion chamber was suitable to characterize the diffusivity of dextran molecules through embroidered scaffolds with or without integrated collagen barriers. The diffusion coefficients were generally significantly lower in scaffolds with barriers compared to those without barriers. No significant differences between diffusion coefficients of both barrier types were detected. Both barriers were cyto-compatible and prevented most of the ACL cells from crossing the barrier, whereby the collagen thread was easier to handle and allowed a higher rate of cell spreading.

Performance Testing of Suspension Plasma Sprayed Thermal Barrier Coatings Produced with Varied Suspension Parameters

Directory of Open Access Journals (Sweden)

Nicholas Curry

2015-07-01

Full Text Available Suspension plasma spraying has become an emerging technology for the production of thermal barrier coatings for the gas turbine industry. Presently, though commercial systems for coating production are available, coatings remain in the development stage. Suitable suspension parameters for coating production remain an outstanding question and the influence of suspension properties on the final coatings is not well known. For this study, a number of suspensions were produced with varied solid loadings, powder size distributions and solvents. Suspensions were sprayed onto superalloy substrates coated with high velocity air fuel (HVAF -sprayed bond coats. Plasma spray parameters were selected to generate columnar structures based on previous experiments and were maintained at constant to discover the influence of the suspension behavior on coating microstructures. Testing of the produced thermal barrier coating (TBC systems has included thermal cyclic fatigue testing and thermal conductivity analysis. Pore size distribution has been characterized by mercury infiltration porosimetry. Results show a strong influence of suspension viscosity and surface tension on the microstructure of the produced coatings.

Activated barrier for protection of special nuclear materials in vital areas

International Nuclear Information System (INIS)

Timm, R.E.; Miranda, J.E.; Reigle, D.L.; Valente, A.D.

1984-01-01

The Argonne National Laboratory and Sandia National Laboratory have recently installed an activated barrier, the Access Denial System (ADS) for the upgrade of safeguards of special nuclear materials. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The installation was the first for the Department of Energy. Subsequently, two additional installations have been completed. The Access Denial System, combined with physical restraints, provide the system delay. The principal advantages of the activated barrier are: (1) it provides an order of magnitude improvement in delay over that of a fixed barrier, (2) it can be added to existing vital areas with a minimum of renovations, (3) existing operations are minimally impacted, and (4) health and safety risks are virtually nonexistent. Hardening of the vital areas using the ADS was accomplished in a cost-effective manner. 3 references, 1 figure, 1 table

Testing of isolation barrier sealing surfaces

Energy Technology Data Exchange (ETDEWEB)

Graves, C.E.

1994-12-15

Isolation barrier doors are to be installed in the 105KE and 105KW basins as part of the 1994 unreviewed safety question (USQ) resolution plan to isolate the fuel storage basin from the fuel discharge chute. Included in this installation is the placement of new sealing surfaces for the barriers by affixing stainless steel plates to existing carbon steel angle bars with a specially formulated epoxy adhesive/sealant material. The sealant is a two-part component consisting of an epoxy resin (the condensation product of bisphenol A and epichlorohydrin) and a curing agent (a proprietary cycloaliphatic polyamine). The sealant is solvent free (complying with air pollution regulations) and capable of withstanding the surrounding radiation fields over an estimated 15-year service life. The epoxy sealant experiences negligible water damage partly because of its hydrophobic (water-repelling) nature. With bond tensile strengths measured at greater than 862 kPa (125 lbf/in{sup 2}), the epoxy sealant is judged acceptable for its intended application. The four-hour pot life of the epoxy sealant provides sufficient time to apply the epoxy, examine the epoxy bead for continuity, and position the stainless steel sealing plates.

Testing of isolation barrier sealing surfaces

International Nuclear Information System (INIS)

Graves, C.E.

1994-01-01

Isolation barrier doors are to be installed in the 105KE and 105KW basins as part of the 1994 unreviewed safety question (USQ) resolution plan to isolate the fuel storage basin from the fuel discharge chute. Included in this installation is the placement of new sealing surfaces for the barriers by affixing stainless steel plates to existing carbon steel angle bars with a specially formulated epoxy adhesive/sealant material. The sealant is a two-part component consisting of an epoxy resin (the condensation product of bisphenol A and epichlorohydrin) and a curing agent (a proprietary cycloaliphatic polyamine). The sealant is solvent free (complying with air pollution regulations) and capable of withstanding the surrounding radiation fields over an estimated 15-year service life. The epoxy sealant experiences negligible water damage partly because of its hydrophobic (water-repelling) nature. With bond tensile strengths measured at greater than 862 kPa (125 lbf/in 2 ), the epoxy sealant is judged acceptable for its intended application. The four-hour pot life of the epoxy sealant provides sufficient time to apply the epoxy, examine the epoxy bead for continuity, and position the stainless steel sealing plates

The role of barriers in the final storage of alpha-contaminated waste

International Nuclear Information System (INIS)

Sousselier, Y.

1981-01-01

The long-term safety of the final storage of waste, for which durations of the order of 10 4 -10 5 years may reasonably be foreseen, is based on the use of various barriers. The first barrier, which is essential in intermediate storage, should have the lowest possible leaching rate in order to play its part in final storage. The role of the second barrier is to provide protection to the first or to serve as a constituent of the overall protection system. The third barrier is expected to be the artificial barrier with the longest lifetime, and should be combined with the fourth so as to add to its effectiveness. The safety analysis should thus study the overall behaviour of the barriers as a whole, which should ensure a very high degree of safety, and also take into account the hazard of intrusion, intentional or otherwise, by future generations. (author)

The protective influence of the locus ceruleus on the blood-brain barrier

International Nuclear Information System (INIS)

Harik, S.I.; McGunigal, T. Jr.

1984-01-01

The functions of the putative noradrenergic innervation of cerebral microvessels from the nucleus locus ceruleus remain ambiguous. Although most evidence indicates that such innervation does not have a major role in the control of cerebral blood flow, there are increasing indications that it modulates transport and permeability functions of the blood-brain barrier. In this study we investigated the effect of unilateral chemical lesioning of the locus ceruleus on the leakage of radioiodinated human serum albumin across the blood-brain barrier. Experiments were performed in awake and restrained rats under steady-state conditions and during drug-induced systemic arterial hypertension, and in anesthetized and paralyzed rats during bicuculline-induced seizures. Both hypertension and seizures are known to be associated with increased leakage of macromolecules across the blood-brain barrier. Albumin leakage into norepinephrine-depleted forebrain structures ipsilateral to the locus ceruleus lesion was compared with that of the contralateral side. There were no side-to-side differences in blood-brain barrier permeability to albumin under steady-state conditions, the stress of restraint, or angiotensin-induced hypertension, or after isoproterenol administration. Norepinephrine-induced hypertension and seizures, however, caused significant increases in albumin leakage into forebrain structures ipsilateral to the lesion. These results suggest that noradrenergic innervation of cerebral microvessels from the locus ceruleus helps preserve the integrity of the blood-brain barrier during pathophysiological states associated with hypertension and increased circulating catecholamines

Comparison of performance test for protective aprons

International Nuclear Information System (INIS)

Fukutomi, Yukimi; Yoshimoto, Masahiro; Kawakami, Toshiaki

1989-01-01

Each one radioprotective apron (lead equivalent, 0.35 mmPb) was commercially available in November 1988 from 7 domestic and 3 foreign companies. According to the JIS standards 4803, these aprons were evaluated for the following items: 1) display of aprons, including packing and the structure; 2) non-breaking test, including appearance, size, lead equivalent, and uniformity; 3) breaking test, including lead equivalent, uniformity, stregth, and structure; 4) feeling of wearing an apron. An overall evaluation revealed that only two aprons were in accordance with the JIS standard. Careful wearing of the protective apron is stressed. (N.K.)

Conservation on international boundaries: the impact of security barriers on selected terrestrial mammals in four protected areas in Arizona, USA.

Directory of Open Access Journals (Sweden)

Jamie W McCallum

Full Text Available Several thousand terrestrial protected areas (PAs lie on international boundaries. Because international boundaries can be focal points for trade, illegal activity and development, such PAs can be vulnerable to a range of anthropogenic threats. There is an increasing trend towards the erection of international boundary infrastructure (including fences, barriers and ditches in many parts of the world, which may reduce the risk of these anthropogenic threats to some PAs. However this may restrict home range and access to resources for some native species. We sought to understand the impacts of these two different types of threat by using camera traps to measure the activity level of humans, native and invasive mammals in four US PAs on the Mexican international boundary. Comparisons were made between treatment areas with barriers and those without. Results showed that puma and coati were more likely to appear in treatment areas without barriers, whereas humans were not observed more frequently in one treatment area over another. The suggestion is that the intermittent fencing present in this part of the world does affect some native species, but does not necessarily restrict the movement of humans (including illegal migrants, who may negatively impact native species.

MATLAB-SIMULINK BASED INFORMATION SUPPORT FOR DIGITAL OVERCURRENT PROTECTION TEST SETS

Directory of Open Access Journals (Sweden)

I. V. Novash

2017-01-01

Full Text Available The implementation of information support for PC-based and hardware-software based sets for digital overcurrent protection devices and their models testing using MatLab-Simulink environment is considered. It is demonstrated that the mathematical modeling of a part of the power system – viz. of the generalized electric power object – could be based on rigid and flexible models. Rigid models implemented on the basis of mathematical description of electrical and magnetic circuits of a power system can be considered as a reference model for the simulation results that have been obtained with the aid of another simulation system to be compared with. It is proposed to implement flexible models for generalized electric power object in the MatLabSimulink environment that includes the SimPowerSystems component library targeted to power system modeling. The features of the parameters calculation of the SimPowerSystems component library blocks that the power system model is formed of are considered. Out of the Simulink standard blocks the models of a wye-connected current transformers were composed as well as the digital overcurrent protection, missing in the component library. A comparison of simulation results of one and the same generalized electric power object implemented in various PC-based software packages was undertaken. The divergence of simulation results did not exceed 3 %; the latter allows us to recommend the MatLab-Simulink environment for information support creation for hardware-software based sets for digital overcurrent protection devices testing. The structure of the hardware-software based set for digital overcurrent protection device testing using the Omicron CMC 356 has been suggested. Time to trip comparison between the real digital protection device МР 801 and the model with the parameters which are exactly match the parameters of the prototype device was carried out using the identical test inputs. The results of the tests

Concrete road barriers subjected to impact loads: An overview

Directory of Open Access Journals (Sweden)

Muhammad Fauzi Bin Mohd. Zain

Full Text Available Abstract Concrete barriers prevent vehicles from entering the opposite lane and going off the road. An important factor in the design of concrete barriers is impact load, which a vehicle exerts upon collision with a concrete barrier. This study suggests that a height of 813 mm, a base width of 600 mm, and a top width of 240 mm are optimum dimensions for a concrete barrier. These dimensions ensure the stability of concrete barriers during vehicle collisions. An analytical and experimental model is used to analyze the concrete barrier design. The LS-DYNA software is utilized to create the analytical models because it can effectively simulate vehicle impact on concrete barriers. Field tests are conducted with a vehicle, whereas laboratory tests are conducted with machines that simulate collisions. Full-scale tests allow the actual simulation of vehicle collisions with concrete barriers. In the vehicle tests, a collision angle of 25°, collision speeds of 100 km per hour, and a vehicle weighing more than 2 t are considered in the reviewed studies. Laboratory tests are performed to test bridge concrete barriers in static condition.

Composite of microgels and lipids as biofilm to restore skin barrier function

NARCIS (Netherlands)

Oudshoorn, M.H.M.

2008-01-01

The mature epidermis is an effective barrier which prevents the body from dehydration and protects it against various environmental influences. If the natural barrier is immature or damaged, the skin barrier is impaired and desiccation occurs. Hence, the regeneration of impaired skin is an essential

USE OF PERFLUOROCARBON TRACER (PFT) TECHNOLOGY FOR SUBSURFACE BARRIER INTEGRITY VERIFICATION AT THE WALDO TEST SITE

Energy Technology Data Exchange (ETDEWEB)

SULLIVAN,T.; HEISER,J.; SENUM,G.; MILLIAN,L.

2000-02-27

Researchers from Brookhaven National Laboratory (BNL) tested perfluorocarbon (PFT) gas tracers on a subsurface barrier with known flaws at the Waldo test facility [operated by Science and Engineering Associates, Inc (SEA)]. The tests involved the use of five unique PFT tracers with a different tracer injected along the interior of each wall of the barrier. A fifth tracer was injected exterior to the barrier to examine the validity of diffusion controlled transport of the PFTs. The PFTs were injected for three days at a nominal flow rate of 15 cm{sup 3}/min and a concentrations in the range of a few hundred ppm. Approximately 65 liters of air laced with tracer was injected for each tracer. The tracers were able to accurately detect the presence of the engineered flaws. Two flaws were detected on the north and east walls and lane flaw was detected on the south and west walls. In addition, one non-engineered flaw at the seam between the north and east walls was also detected. The use of multiple tracers provided independent confirmation of the flaws and permitted a distinction between tracers arriving at a monitoring port after being released from a nearby flaw and non-engineered flaws. The PFTs detected the smallest flaw, 0.5 inches in diameter. Visual inspection of the data showed excellent agreement with the known flaw locations and the relative size of the flaws was accurately estimated.

Impact Testing of Orbiter Thermal Protection System Materials

Science.gov (United States)

Kerr, Justin

2006-01-01

This viewgraph presentation reviews the impact testing of the materials used in designing the shuttle orbiter thermal protection system (TPS). Pursuant to the Columbia Accident Investigation Board recommendations a testing program of the TPS system was instituted. This involved using various types of impactors in different sizes shot from various sizes and strengths guns to impact the TPS tiles and the Leading Edge Structural Subsystem (LESS). The observed damage is shown, and the resultant lessons learned are reviewed.

Seasonal breaching of coastal barriers

NARCIS (Netherlands)

Tuan, Thieu Quang

2007-01-01

Natural or unintended breaching can be catastrophic, causing loss of human lives and damage to infrastructures, buildings and natural habitats. Quantitative understand-ing of coastal barrier breaching is therefore of great importance to vulnerability as-sessment of protection works as well as to

Phonic Attenuation due to Screen-Barriers

Directory of Open Access Journals (Sweden)

Vasile Bacria

2011-10-01

Full Text Available The technique of noise decreasing admits two basic approaches: an active approach and a passive one. In the frame of passive method one can count the employment of screen-barriers. In this paper we present some considerations on sound attenuation due to screen-barriers emphasizing the elements which influence it. The elucidation of these elements is made by measurements. The obtained results can be applied in every other practical situation concerning the protection against noise.

Reliability performance testing of totally encapsulating chemical protective suits

International Nuclear Information System (INIS)

Johnson, J.S.; Swearengen, P.M.

1991-01-01

The need to assure a high degree of reliability for totally encapsulating chemical protective (TECP) suits has been recognized by Lawrence Livermore National Laboratory's (LLNL) Hazards Control Department for some time. The following four tests were proposed as necessary to provide complete evaluation of TECP suit performance: 1. Quantitative leak test (ASTM draft), 2. Worst-case chemical exposure test (conceptual), 3. Pressure leak-rate test (complete, ASTM F1057-87), and 4. Chemical leak-rate test (ASTM draft). This paper reports on these tests which should be applied to measuring TECP suit performance in two stages: design qualification tests and field use tests. Test 1, 2, and 3 are used as design qualification tests, and tests 3 and 4 are used as field use tests

Use of protection motivation theory, affect, and barriers to understand and predict adherence to outpatient rehabilitation.

Science.gov (United States)

Grindley, Emma J; Zizzi, Samuel J; Nasypany, Alan M

2008-12-01

Protection motivation theory (PMT) has been used in more than 20 different health-related fields to study intentions and behavior, albeit primarily outside the area of injury rehabilitation. In order to examine and predict patient adherence behavior, this study was carried out to explore the use of PMT as a screening tool in a general sample of people with orthopedic conditions. New patients who were more than 18 years old and who were prescribed 4 to 8 weeks of physical therapy treatment (n=229) were administered a screening tool (Sports Injury Rehabilitation Beliefs Scale, Positive and Negative Affect Schedule, and a barriers checklist) prior to treatment. Participants' adherence was assessed with several attendance measures and an in-clinic assessment of behavior. Statistical analyses included correlation, chi-square, multiple regression, and discriminant function analyses. A variety of relationships among affect, barriers, and PMT components were evident. In-clinic behavior and attendance were influenced by affect, whereas dropout status was predicted by affect, severity, self-efficacy, and age. The screening tool used in this study may assist in identifying patients who are at risk for poor adherence and provide valuable information to enhance provider-patient relationships and foster patient adherence. However, it is recommended that more research be conducted to further understand the impact of variables on patient adherence and that the screening tool be enhanced to increase its predictive ability.

Laboratory tests of overpressure differential systems for smoke protection of lobbies

Science.gov (United States)

Szałański, Paweł; Misiński, Jacek

2017-11-01

Paper presents the methodology of laboratory tests for ventilation overpressure differential systems for smoke protection of lobbies. Research area consists of two spaces representing the lobby and the area under fire equipped with proper ventilation installation. This allows testing of overpressure differential systems for smoke protection of lobbies. Moreover, piece of laboratory tests results for two selected smoke protection systems for lobbies are presented. First one is standard system with constantly opened transfer-damper mounted between lobby and area under fire. Second one - system with so called "electronic transfer" based on two dampers (supplying air to a lobby and to unprotected area alternatively). Opening and closing both dampers is electronically controlled. Changes of pressure difference between lobby and fire affected area during closing and opening doors between those spaces is presented. Conclusions, concerning the possibility of meeting the time period criteria of pressure difference stabilization required by standards, are presented and discussed for both systems.

A chromia forming thermal barrier coating system

Energy Technology Data Exchange (ETDEWEB)

Taylor, M.P.; Evans, H.E. [Metallurgy and Materials, The University of Birmingham, Birmingham, B15 2TT (United Kingdom); Gray, S.; Nicholls, J.R. [Surface Science and Engineering Centre, Cranfield University, Cranfield, MK43 0AL (United Kingdom)

2011-07-15

Conventional thermal barrier coating (TBC) systems consist of an insulating ceramic topcoat, a bond coat for oxidation protection and the underlying superalloy designed to combat the oxidising conditions in aero- and land-based gas turbines. Under high-temperature oxidation, the use of an alumina forming bond coat is warranted, thus all current TBC systems are optimised for the early formation of a dense, protective thermally grown oxide (TGO) of alumina. This also offers protection against Type I hot corrosion but a chromia layer gives better protection against Type II corrosion and intermediate temperatures, the conditions found in land-based gas turbines. In this paper the authors present the first known results for a chromia forming TBC system. Tests have been performed under oxidising conditions, up to 1000 h, at temperatures between 750 C and 900 C, and under Type I (900 C) and Type II (700 C) hot corrosion conditions up to 500 h. Under all these conditions no cracking, spallation or degradation was observed. Examination showed the formation of an adherent, dense chromia TGO at the bond coat / topcoat interface. These initial results are very encouraging and the TGO thicknesses agree well with comparable results reported in the literature. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Protection against malevolent use of vehicles at Nuclear Power Plants. Vehicle barrier system selection guidance

International Nuclear Information System (INIS)

Nebuda, D.T.

1994-08-01

This manual provides a simplified procedure for selecting land vehicle barriers that will stop the design basis vehicle threat adopted by the U.S. Nuclear Regulatory Commission. Proper selection and construction of vehicle barriers should prevent intrusion of the design basis vehicle. In addition, vital safety related equipment should survive a design basis vehicle bomb attack when vehicle barriers are properly selected, sited, and constructed. This manual addresses passive vehicle barriers, active vehicle barriers, and site design features that can be used to reduce vehicle impact velocity

16 CFR 1204.4 - Electric shock protection tests.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Electric shock protection tests. 1204.4 Section 1204.4 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT... the cable shall be between 28 and 29 feet (8.5 to 8.8 meters) above a horizontal plane through the...

Advanced physical protection systems for nuclear materials

International Nuclear Information System (INIS)

Jones, O.E.

1976-01-01

Because of the increasing incidence of terrorism, there is growing concern that nuclear materials and facilities need improved physical protection against theft, diversion, or sabotage. Physical protection systems for facilities or transportation which have balanced effectiveness include information systems, access denial systems, adequate and timely response, recovery capability, and use denial methods for despoiling special nuclear materials (SNM). The role of these elements in reducing societal risk is described; however, it is noted that, similar to nuclear war, the absolute risks of nuclear theft and sabotage are basically unquantifiable. Sandia Laboratories has a major US Energy Research and Development Administration (ERDA) role in developing advanced physical protection systems for improving the security of both SNM and facilities. These activities are surveyed in this paper. A computer simulation model is being developed to assess the cost-effectiveness of alternative physical protection systems under various levels of threat. Improved physical protection equipment such as perimeter and interior alarms, secure portals, and fixed and remotely activated barriers is being developed and tested. In addition, complete prototype protection systems are being developed for representative nuclear facilities. An example is shown for a plutonium storage vault. The ERDA safe-secure transportation system for highway shipments of all significant quantities of government-owned SNM is described. Adversary simulation as a tool for testing and evaluating physical protection systems is discussed. Finally, a list of measures is given for assessing overall physical protection system performance. (author)

Advanced physical protection systems for nuclear materials

International Nuclear Information System (INIS)

Jones, O.E.

1975-10-01

Because of the increasing incidence of terrorism, there is growing concern that nuclear materials and facilities need improved physical protection against theft, diversion, or sabotage. Physical protection systems for facilities or transportation which have balanced effectiveness include information systems, access denial systems, adequate and timely response, recovery capability, and use denial methods for despoiling special nuclear materials (SNM). The role of these elements in reducing societal risk is described; however, it is noted that, similar to nuclear war, the absolute risks of nuclear theft and sabotage are basically unquantifiable. Sandia Laboratories has a major Energy Research and Development Administration (ERDA) role in developing advanced physical protection systems for improving the security of both SNM and facilities. These activities are surveyed. A computer simulation model is being developed to assess the cost-effectiveness of alternative physical protection systems under various levels of threat. Improved physical protection equipment such as perimeter and interior alarms, secure portals, and fixed and remotely-activated barriers is being developed and tested. In addition, complete prototype protection systems are being developed for representative nuclear facilities. An example is shown for a plutonium storage vault. The ERDA safe-secure transportation system for highway shipments of all significant quantities of government-owned SNM is described. Adversary simulation as a tool for testing and evaluating physical protection systems is discussed. A list of measures is given for assessing overall physical protection system performance. (auth)

Thermal Gradient Cyclic Behavior of a Thermal/Environmental Barrier Coating System on SiC/SiC Ceramic Matrix Composites

Science.gov (United States)

Zhu, Dongming; Lee, Kang N.; Miller, Robert A.

2002-01-01

Thermal barrier and environmental barrier coatings (TBCs and EBCs) will play a crucial role in future advanced gas turbine engines because of their ability to significantly extend the temperature capability of the ceramic matrix composite (CMC) engine components in harsh combustion environments. In order to develop high performance, robust coating systems for effective thermal and environmental protection of the engine components, appropriate test approaches for evaluating the critical coating properties must be established. In this paper, a laser high-heat-flux, thermal gradient approach for testing the coatings will be described. Thermal cyclic behavior of plasma-sprayed coating systems, consisting of ZrO2-8wt%Y2O3 thermal barrier and NASA Enabling Propulsion Materials (EPM) Program developed mullite+BSAS/Si type environmental barrier coatings on SiC/SiC ceramic matrix composites, was investigated under thermal gradients using the laser heat-flux rig in conjunction with the furnace thermal cyclic tests in water-vapor environments. The coating sintering and interface damage were assessed by monitoring the real-time thermal conductivity changes during the laser heat-flux tests and by examining the microstructural changes after the tests. The coating failure mechanisms are discussed based on the cyclic test results and are correlated to the sintering, creep, and thermal stress behavior under simulated engine temperature and heat flux conditions.

Barriers to A1C testing among a managed care population.

Science.gov (United States)

Delaronde, Steven

2005-01-01

The purpose of this study is to explore reasons adults with diabetes do not receive at least 2 A1C tests per year as recommended by the American Diabetes Association (ADA). ConnectiCare, a regional managed care company based in Farmington, Connecticut, identified adult members with diabetes who did not have a medical claim for an A1C laboratory test from their physician. A questionnaire was sent to 740 randomly selected members asking them to report the number of A1C tests they received in the past 12 months and reasons for not receiving the number of tests recommended by the ADA. After sending an automated telephone reminder to nonrespondents, a 26% (n = 192) response rate was achieved. Thirty-three percent of respondents (n = 63) reported having diabetes and receiving fewer than 2 A1C tests in the past year. Respondents were equally divided between men and women, with a mean age of 58 years. The primary reasons given for not obtaining at least 2 A1C tests as recommended by the ADA were that respondents were unaware that the test is recommended (49%), not informed of the need for the test by their physician (38%), never heard of the A1C test (33%), and not seen regularly by their physician (19%). Diabetes self-management education remains an important means of encouraging adherence to important ADA recommendations such as regular A1C testing. Barriers to A1C testing can be addressed in multiple settings, including individual and group education, disease management programs, and physician education.

"Targeted disruption of the epithelial-barrier by Helicobacter pylori"

Directory of Open Access Journals (Sweden)

Wroblewski Lydia E

2011-11-01

Full Text Available Abstract Helicobacter pylori colonizes the human gastric epithelium and induces chronic gastritis, which can lead to gastric cancer. Through cell-cell contacts the gastric epithelium forms a barrier to protect underlying tissue from pathogenic bacteria; however, H. pylori have evolved numerous strategies to perturb the integrity of the gastric barrier. In this review, we summarize recent research into the mechanisms through which H. pylori disrupts intercellular junctions and disrupts the gastric epithelial barrier.

Thermal Cycling and High-Temperature Corrosion Tests of Rare Earth Silicate Environmental Barrier Coatings

Science.gov (United States)

Darthout, Émilien; Gitzhofer, François

2017-12-01

Lutetium and yttrium silicates, enriched with an additional secondary zirconia phase, environmental barrier coatings were synthesized by the solution precursor plasma spraying process on silicon carbide substrates. A custom-made oven was designed for thermal cycling and water vapor corrosion testing. The oven can test four specimens simultaneously and allows to evaluate environmental barrier performances under similar corrosion kinetics compared to turbine engines. Coatings structural evolution has been observed by SEM on the polished cross sections, and phase composition has been analyzed by XRD. All coatings have been thermally cycled between 1300 °C and the ambient temperature, without spallation, due to their porosity and the presence of additional secondary phase which increases the thermal cycling resistance. During water vapor exposure at 1200 °C, rare earth disilicates showed a good stability, which is contradictory with the literature, due to impurities—such as Si- and Al-hydroxides—in the water vapor jets. The presence of vertical cracks allowed the water vapor to reach the substrate and then to corrode it. It has been observed that thin vertical cracks induced some spallation after 24 h of corrosion.

A cross sectional survey of the barriers for implementing rapid HIV testing among French general practitioners.

Science.gov (United States)

Fraisse, Thibaut; Fourcade, Camille; Brazes-Sanz, Julie; Koumar, Yatrika; Lavigne, Jean Philippe; Sotto, Albert; Laureillard, Didier

2016-10-01

In France, almost 30,000 people are unaware of their HIV-positive status. Innovative screening strategies are essential to reach this population. The aim of this study was to describe the acceptability of rapid HIV testing (RHT) among French general practitioners (GPs) working in the south of France and barriers for implementing this strategy. We analysed an anonymous questionnaire sent by mail to GPs about demographic data, routine practice, knowledge of RHT and barriers to its use. Between 1 April and 30 September 2013, out of the 165 GPs contacted, 78 returned the questionnaires. The GPs' mean age was 52 years; 49 were men. Fifty-one GPs reported that their registered patients included at least one HIV-infected person and 70 GPs reported taking care of high-risk patients. Sixty-three percent of GPs reported being interested in using RHT in their daily practice. The main reasons reported by uninterested GPs were: greater confidence in standard HIV testing, difficulties including RHT during the routine consultation, difficulties to screen for other sexually transmitted infections simultaneously, and difficulties to deliver a positive result. French National Authorities for Health propose to screen the population at least once in their lifetime and high-risk people at least once a year. In order to achieve this aim, RHT should be included in the GPs' arsenal for HIV testing. We showed a high acceptability of RHT by GPs. If specific and adapted training is developed, and if solutions to barriers reported by GPs are found, RHT could be implemented in to their routine activity. © The Author(s) 2016.

Numerical simulation of flood barriers

Science.gov (United States)

Srb, Pavel; Petrů, Michal; Kulhavý, Petr

This paper deals with testing and numerical simulating of flood barriers. The Czech Republic has been hit by several very devastating floods in past years. These floods caused several dozens of causalities and property damage reached billions of Euros. The development of flood measures is very important, especially for the reduction the number of casualties and the amount of property damage. The aim of flood control measures is the detention of water outside populated areas and drainage of water from populated areas as soon as possible. For new flood barrier design it is very important to know its behaviour in case of a real flood. During the development of the barrier several standardized tests have to be carried out. Based on the results from these tests numerical simulation was compiled using Abaqus software and some analyses were carried out. Based on these numerical simulations it will be possible to predict the behaviour of barriers and thus improve their design.

Design and performance evaluation of a 1000-year evapotranspiration-capillary surface barrier.

Science.gov (United States)

Zhang, Zhuanfang Fred; Strickland, Christopher E; Link, Steven O

2017-02-01

Surface barrier technology is used to isolate radioactive waste and to reduce or eliminate recharge water to the waste zone for 1000 years or longer. However, the design and evaluation of such a barrier is challenging because of the extremely long design life. After establishing a set of design and performance objectives, a package of design solutions was developed for 1000-year surface barriers over nuclear waste sites. The Prototype Hanford Barrier (PHB) was then constructed in 1994 in the field over an existing waste site as a demonstration. The barrier was tested to evaluate surface-barrier design and performance at the field scale under conditions of enhanced and natural precipitation and of no vegetation. The monitoring data demonstrate that the barrier satisfied nearly all objectives in the past two decades. The PHB far exceeded the Resource Conservation and Recovery Act criteria, functioned in Hanford's semiarid climate, limited drainage to well below the 0.5 mm yr -1 performance criterion, limited runoff, and minimized erosion and bio-intrusion. Given the two-decade record of successful performance and consideration of the processes and mechanisms that could affect barrier stability and hydrology in the future, the results suggest the PHB is very likely to perform for its 1000-year design life. This conclusion is based on two assumptions: (1) the exposed subgrade receives protection against erosion and (2) institutional controls prevent inadvertent human activity at the barrier. The PHB design can serve as the basis for site-specific barriers over waste sites containing underground nuclear waste, uranium mine tailings, and hazardous mine waste. Copyright © 2016 Elsevier Ltd. All rights reserved.

The influence of acculturation and breast cancer-specific distress on perceived barriers to genetic testing for breast cancer among women of African descent.

Science.gov (United States)

Sussner, Katarina M; Thompson, Hayley S; Jandorf, Lina; Edwards, Tiffany A; Forman, Andrea; Brown, Karen; Kapil-Pair, Nidhi; Bovbjerg, Dana H; Schwartz, Marc D; Valdimarsdottir, Heiddis B

2009-09-01

Rising health disparities are increasingly evident in relation to use of genetic services (including genetic counseling and testing) for breast cancer risk, with women of African descent less likely to use genetic services compared with Whites. Meanwhile, little is known regarding potential within-group acculturation and psychological differences underlying perceived barriers to genetic testing among women of African descent. Hypothesized contributions of acculturation factors and breast cancer-specific distress to perceived barriers to genetic testing were examined with a statistical analysis of baseline data from 146 women of African descent (56% US born and 44% foreign born) meeting genetic breast cancer risk criteria and participating in a larger longitudinal study that included the opportunity for free genetic counseling and testing. Perceived barriers assessed included: (1) anticipation of negative emotional reactions, (2) stigma, (3) confidentiality concerns, (4) family-related worry, and (5) family-related guilt associated with genetic testing. In multivariate analyses, being foreign born was a significant predictor of anticipated negative emotional reactions about genetic testing (beta=0.26; SE=0.11; p=0.01). Breast cancer-specific distress scores (avoidance symptoms) were positively related to anticipated negative emotional reactions (beta=0.02; SE=0.005; p=barriers to genetic testing among women of African descent. The potential utility of culturally tailored genetic counseling services taking into account such influences and addressing emotional and psychological concerns of women considering genetic testing for breast cancer should be investigated.

Design of test JIG for centralized interlock and protection module of ITER-India Gyrotron Test Facility

International Nuclear Information System (INIS)

Rathod, Vipal; Rao, S.L.; Edappala, Praveenlal; Rajpal, Rachana

2017-01-01

Fast Interlock and protection system plays very crucial role in ensuring the safe and reliable operation of high power RF sources such as a Gyrotron system. Critical Protection Interlocks are generally implemented using hardwired components and are required to have a response time as fast as < 10 μs. In this context, an Industrial grade prototype Centralized Interlock and Protection Module (CIM) based on ITER-India design has been developed successfully with the help of local industry. This paper presents the complete requirements, approach, detailed design concept and current status of Test JIG in detail

Barriers and facilitators for men to attend prenatal care and obtain HIV voluntary counseling and testing in Brazil.

Science.gov (United States)

Yeganeh, Nava; Simon, Mariana; Mindry, Deborah; Nielsen-Saines, Karin; Chaves, Maria Cristina; Santos, Breno; Melo, Marineide; Mendoza, Brenna; Gorbach, Pamina

2017-01-01

Providing HIV voluntary counseling and testing (VCT) to men who attend their partner's prenatal care is an intervention with potential to reduce HIV transmission to women and infants during the vulnerable period of pregnancy. Little is known about the acceptability of this intervention in global settings outside of Africa. We conducted in-depth qualitative interviews to evaluate potential barriers and facilitators to prenatal care attendance for HIV VCT with 20 men who did and 15 men who did not attend prenatal care with their partners at Hospital Conceiçao in Porto Alegre, Brazil. Men were recruited at the labor and delivery unit at Hospital Conceiçao via a scripted invitation while visiting their newborn infant. Interviews lasted from 35-55 minutes and were conducted in Portuguese by a local resident trained extensively in qualitative methods. All interviews were transcribed verbatim, translated, and then analyzed using Atlast.ti software. An analysis of themes was then conducted using direct quotes and statements. We applied and adapted the AIDS Risk Reduction Theoretical Model and HIV Testing Decisions Model to the qualitative data to identify themes in the 35 interviews. If offered HIV testing during prenatal care, all men in both groups stated they would accept this intervention. Yet, individual, relationship and systemic factors were identified that affect these Brazilian men's decision to attend prenatal care, informing our final conceptual model. The men interviewed had a general understanding of the value of HIV prevention of mother to child transmission. They also described open and communicative relationships with their significant others and displayed a high level of enthusiasm towards optimizing the health of their expanding family. The major barriers to attending prenatal care included perceived stigma against HIV infected individuals, men's lack of involvement in planning of the pregnancy as well as inconvenient scheduling of prenatal care, due to

Barriers and facilitators for men to attend prenatal care and obtain HIV voluntary counseling and testing in Brazil.

Directory of Open Access Journals (Sweden)

Nava Yeganeh

Full Text Available Providing HIV voluntary counseling and testing (VCT to men who attend their partner's prenatal care is an intervention with potential to reduce HIV transmission to women and infants during the vulnerable period of pregnancy. Little is known about the acceptability of this intervention in global settings outside of Africa.We conducted in-depth qualitative interviews to evaluate potential barriers and facilitators to prenatal care attendance for HIV VCT with 20 men who did and 15 men who did not attend prenatal care with their partners at Hospital Conceiçao in Porto Alegre, Brazil. Men were recruited at the labor and delivery unit at Hospital Conceiçao via a scripted invitation while visiting their newborn infant. Interviews lasted from 35-55 minutes and were conducted in Portuguese by a local resident trained extensively in qualitative methods. All interviews were transcribed verbatim, translated, and then analyzed using Atlast.ti software. An analysis of themes was then conducted using direct quotes and statements. We applied and adapted the AIDS Risk Reduction Theoretical Model and HIV Testing Decisions Model to the qualitative data to identify themes in the 35 interviews.If offered HIV testing during prenatal care, all men in both groups stated they would accept this intervention. Yet, individual, relationship and systemic factors were identified that affect these Brazilian men's decision to attend prenatal care, informing our final conceptual model. The men interviewed had a general understanding of the value of HIV prevention of mother to child transmission. They also described open and communicative relationships with their significant others and displayed a high level of enthusiasm towards optimizing the health of their expanding family. The major barriers to attending prenatal care included perceived stigma against HIV infected individuals, men's lack of involvement in planning of the pregnancy as well as inconvenient scheduling of

Barrier pillar between production panels in coal mine

Energy Technology Data Exchange (ETDEWEB)

Zingano, Andre Cezar; Koppe, Jair Carlos; Costa, Joao Felipe C.L. [Universidade Federal do Rio Grande do Sul, Porto Alegre (Brazil)

2007-07-01

The function of the barrier pillar is to protect the mining panel in activity from the abutment load of adjacent mining panels that were mined. In the case of underground mines in Santa Catarina State, the barrier pillar has functioned to protect the main entries of the mine against pillar failure from old mining panels. The objective of this paper is to verify the application of the empirical method to design barrier pillars as proposed by Peng (1986), using numerical simulation following the mining geometry of the coal mines in Santa Catarina State. Two-dimensional numerical models were built taking into account the geometry of the main entries and mining panels for different overburden thickness, and considering the geomechanical properties for the rock mass that forms the roof-pillar-floor system for the Bonito coal vein. The results of the simulations showed that the empirical method to determine the barrier pillar width is valid for the studied coal vein and considered mine geometry. Neither did the pillar at the main entry become overstressed due to adjacent mine panels, nor did the roof present any failure due to stress redistribution. 9 refs., 6 figs., 5 tabs.

Preliminary tests of an electrokinetic barrier to prevent heavy metal pollution of soils

International Nuclear Information System (INIS)

Lynch, R.J.; Muntoni, A.; Ruggeri, R.; Winfield, K.C.

2007-01-01

Sardinia has to deal with significant environmental problems related to heavy-metal contamination, mainly located at its abandoned mining districts. In particular, acid mine drainage management and groundwater pollution are typical problems associated with mining activities which constitute a serious threat to human health. To prevent contaminant spread over the adjacent environment, it is of great interest to consider using an electric field as a containment fence to counteract pollutant transport. In this application, contaminant transport due to a hydraulic gradient driving force is prevented by the combined effect of electro-osmosis and electro-migration. Although there are other alternative containment technologies, the electrokinetic fence offers many advantages, as it is easy to operate, there is a minimal exposure to the operating personnel and it is likely to be effective for a wide range of contaminants. In this work, both one-dimensional (1D) and two-dimensional (2D) tests have been carried out. In the 1D tests, the efficiency of an electrokinetic barrier to prevent cadmium from polluting an uncontaminated sample was investigated; soil pH, metal concentration and current intensity have been monitored; results indicate that the barrier can prevent or significantly reduce heavy-metal contamination from spreading against a hydraulic gradient of 7. In 2D tests, two rows of electrodes inserted in a horizontally flat soil tank were used to generate an electric field. It was found that an electric field of 125 V m -1 was sufficient to prevent significant copper incursion from a contaminant flow under a hydraulic gradient of 1.3

Radiation protection for particle accelerators

International Nuclear Information System (INIS)

Verdu, G.; Rodenas, J.; Campayo, J.M.

1992-01-01

It a a great number of medical installations in spain using particle accelerators for radiotherapy. It is obvious the importance of an accurate estimation of the doses produced in these installations that may be received by health workers, patients or public. The lower values of dose limits established in the new ICRP recommendations imply a recalculation of items concerning such installations. In our country, specific guidelines for radiation protection in particle accelerators facilities have not been yet developed, however two possible guides can be used, NCRP report number 51 and DIN Standard 6847. Both have been analyzed comparatively in the paper, and major remarks have been summarized. Interest has been focused on thickness estimation of shielding barriers in order to verify whether must be modified to comply with the new dose limits. Primary and secondary barriers for a Mevatron used in a Medical Center, have been calculated and the results have been compared with actual data obtained from the installation, to test the adequacy of shielding barriers and radioprotection policies. The results obtained are presented and analyzed in order to state the implications of the new ICRP recommendations. (author)

Barrier erosion control test plan: Gravel mulch, vegetation, and soil water interactions

Energy Technology Data Exchange (ETDEWEB)

Waugh, W.J.; Link, S.O. (Pacific Northwest Lab., Richland, WA (USA))

1988-07-01

Soil erosion could reduce the water storage capacity of barriers that have been proposed for the disposal of near-surface waste at the US Department of Energy's Hanford Site. Gravel mixed into the top soil surface may create a self-healing veneer that greatly retards soil loss. However, gravel admixtures may also enhance infiltration of rainwater, suppress plant growth and water extraction, and lead to the leaching of underlying waste. This report describes plans for two experiments that were designed to test hypotheses concerning the interactive effects of surface gravel admixtures, revegetation, and enhanced precipitation on soil water balance and plant abundance. The first experiment is a factorial field plot set up on the site selected as a soil borrow area for the eventual construction of barriers. The treatments, arranged in a a split-split-plot design structure, include two densities of gravel admix, a mixture of native and introduced grasses, and irrigation to simulate a wetter climate. Changes in soil water storage and plant cover are monitored with neutron moisture probes and point intercept sampling, respectively. The second experiment consists of an array of 80 lysimeters containing several different barrier prototypes. Surface treatments are similar to the field-plot experiment. Drainage is collected from a valve at the base of each lysimeter tube, and evapotranspiration is estimated by subtraction. The lysimeters are also designed to be coupled to a whole-plant gas exchange system that will be used to conduct controlled experiments on evapotranspiration for modeling purposes. 56 refs., 6 figs., 8 tabs.

New research opportunities for roadside safety barriers improvement

Science.gov (United States)

Cantisani, Giuseppe; Di Mascio, Paola; Polidori, Carlo

2017-09-01

Among the major topics regarding the protection of roads, restraint systems still represent a big opportunity in order to increase safety performances. When accidents happen, in fact, the infrastructure can substantially contribute to the reduction of consequences if its marginal spaces are well designed and/or effective restraint systems are installed there. Nevertheless, basic concepts and technology of road safety barriers have not significantly changed for the last two decades. The paper proposes a new approach to the study aimed to define possible enhancements of restraint safety systems performances, by using new materials and defining innovative design principles. In particular, roadside systems can be developed with regard to vehicle-barrier interaction, vehicle-oriented design (included low-mass and extremely low-mass vehicles), traffic suitability, user protection, working width reduction. In addition, thanks to sensors embedded into the barriers, it is also expected to deal with new challenges related to the guidance of automatic vehicles and I2V communication.

Barriers to investment in emerging power markets

Energy Technology Data Exchange (ETDEWEB)

Beardsworth, Jr, J J [Hunton and Williams, Richmond, VA (United States)

1994-12-31

Investing in private power projects in developing countries is a very different issue from investment in the US or the UK. There are many investment barriers not present in developed nations. Firstly investment barriers need to be identified. Trouble may be encountered with legal authorization; the regulatory framework; government guarantees; fuel supply security; lender protection; labour laws and local commercial restrictions such as profits repatriation, currency convertibility, and taxes. Political barriers may also be encountered in the form of: government commitments and support; funding sources; political unrest; religion; and relationships with other countries. Investment barriers may be minimised by persuading the government to remove any legal barriers; the contract has then to be agreed. Factors in a successful contract include: power purchase agreements; fuel agreements; and implementation agreements. It is vital to have a source of information on local rules and customs, by working with local companies and employing local attorneys.

An activated barrier for protection of special nuclear materials in vital areas

International Nuclear Information System (INIS)

Timm, R.E.; Miranda, J.E.

1984-01-01

The Argonne National Laboratory and Sandia National Laboratory have recently installed an activated barrier, the Access Denial System (ADS) for the upgrade of safeguards of special nuclear materials. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The installation was the first for the Department of Energy. Subsequently, two additional installations have been completed. The Access Denial System, combined with physical restraints, provide the system delay. The principal advantages of the activated barrier are: (1) it provides an order of magnitude improvement in delay over that of a fixed barrier, (2) it can be added to existing vital areas with a minimum of renovations, (3) existing operations are minimally impacted, and (4) health and safety risks are virtually nonexistent. Hardening of the vital areas using the ADS was accomplished in a costeffective manner

Revealing barriers and facilitators to use a new genetic test: comparison of three user involvement methods.

Science.gov (United States)

Rhebergen, Martijn D F; Visser, Maaike J; Verberk, Maarten M; Lenderink, Annet F; van Dijk, Frank J H; Kezic, Sanja; Hulshof, Carel T J

2012-10-01

We compared three common user involvement methods in revealing barriers and facilitators from intended users that might influence their use of a new genetic test. The study was part of the development of a new genetic test on the susceptibility to hand eczema for nurses. Eighty student nurses participated in five focus groups (n = 33), 15 interviews (n = 15) or questionnaires (n = 32). For each method, data were collected until saturation. We compared the mean number of items and relevant remarks that could influence the use of the genetic test obtained per method, divided by the number of participants in that method. Thematic content analysis was performed using MAXQDA software. The focus groups revealed 30 unique items compared to 29 in the interviews and 21 in the questionnaires. The interviews produced more items and relevant remarks per participant (1.9 and 8.4 pp) than focus groups (0.9 and 4.8 pp) or questionnaires (0.7 and 2.3 pp). All three involvement methods revealed relevant barriers and facilitators to use a new genetic test. Focus groups and interviews revealed substantially more items than questionnaires. Furthermore, this study suggests a preference for the use of interviews because the number of items per participant was higher than for focus groups and questionnaires. This conclusion may be valid for other genetic tests as well.

Thermal barrier coatings application in diesel engines

Science.gov (United States)

Fairbanks, J. W.

1995-01-01

Commercial use of thermal barrier coatings in diesel engines began in the mid 70's by Dr. Ingard Kvernes at the Central Institute for Industrial Research in Oslo, Norway. Dr. Kvernes attributed attack on diesel engine valves and piston crowns encountered in marine diesel engines in Norwegian ships as hot-corrosion attributed to a reduced quality of residual fuel. His solution was to coat these components to reduce metal temperature below the threshold of aggressive hot-corrosion and also provide protection. Roy Kamo introduced thermal barrier coatings in his 'Adiabatic Diesel Engine' in the late 70's. Kamo's concept was to eliminate the engine block water cooling system and reduce heat losses. Roy reported significant performance improvements in his thermally insulated engine at the SAE Congress in 1982. Kamo's work stimulates major programs with insulated engines, particularly in Europe. Most of the major diesel engine manufacturers conducted some level of test with insulated combustion chamber components. They initially ran into increased fuel consumption. The German engine consortium had Prof. Woschni of the Technical Institute in Munich. Woschni conducted testing with pistons with air gaps to provide the insulation effects. Woschni indicated the hot walls of the insulated engine created a major increase in heat transfer he refers to as 'convection vive.' Woschni's work was a major factor in the abrupt curtailment of insulated diesel engine work in continental Europe. Ricardo in the UK suggested that combustion should be reoptimized for the hot-wall effects of the insulated combustion chamber and showed under a narrow range of conditions fuel economy could be improved. The Department of Energy has supported thermal barrier coating development for diesel engine applications. In the Clean Diesel - 50 Percent Efficient (CD-50) engine for the year 2000, thermal barrier coatings will be used on piston crowns and possibly other components. The primary purpose of the

A field test of a waste containment technology using a new generation of injectable barrier liquids

International Nuclear Information System (INIS)

Moridis, G.; Apps, J.; Persoff, P.; Myer, L.; Muller, S.; Pruess, K.; Yen, P.

1996-08-01

A first stage field injection of a new generation of barrier liquids was successfully completed. Two types of barrier liquids, colloidal silica (CS) and polysiloxane (PSX), were injected into heterogeneous unsaturated deposits of sand, silt, and gravel typical of many of the arid DOE cleanup sites and particularly analogous to the conditions of the Hanford Site. Successful injection by commercially available chemical grouting equipment and the tube-a-manchette technique was demonstrated. Excavation of the grout bulbs permitted visual evaluation of the soil permeation by the grout, as well as sample collection. Both grouts effectively permeated all of the formation. The PSX visually appeared to perform better, producing a more uniform and symmetric permeation regardless of heterogeneity, filling large as well as small pores and providing more structural strength than the CS. Numerical simulation of the injection tests incorporated a stochastic field to represent site heterogeneity and was able to replicate the general test behavior. Tiltmeters were used successfully to monitor surface displacements during grout injection

Design and testing of integrated circuits for reactor protection channels

International Nuclear Information System (INIS)

Battle, R.E.; Vandermolen, R.I.; Jagadish, U.; Swail, B.K.; Naser, J.

1995-01-01

Custom and semicustom application-specific integrated circuit design and testing methods are investigated for use in research and commercial nuclear reactor safety systems. The Electric Power Research Institute and Oak Ridge National Laboratory are working together through a cooperative research and development agreement to apply modern technology to a nuclear reactor protection system. The purpose of this project is to demonstrate to the nuclear industry an alternative approach for new or upgrade reactor protection and safety system signal processing and voting logic. Motivation for this project stems from (1) the difficulty of proving that software-based protection systems are adequately reliable, (2) the obsolescence of the original equipment, and (3) the improved performance of digital processing. A demonstration model for protection system of PWR reactor has been designed and built

Protective Effects of Let-7b on the Expression of Occludin by Targeting P38 MAPK in Preventing Intestinal Barrier Dysfunction

Directory of Open Access Journals (Sweden)

Zhihua Liu

2018-01-01

Full Text Available Background/Aims: Let-7b was dramatically reduced after a dicer knockout of mice with intestinal barrier function injuries. This paper aims to investigate the molecular mechanism of let-7b by targeting p38 MAPK in preventing intestinal barrier dysfunction. Methods: A total of 186 patients were enrolled, with 93 in the control group and 93 in the PRO group. Only 158 patients completed the entire study, whereas the others either did not meet the inclusion criteria or refused to participate. To further verify the role of let-7b, intestinal epithelial conditional knockout (IKO mice of mmu-let-7b model were established. Serum let-7b, zonulin, IL-6, and TNF-α concentrations were measured by ELISA or quantitative RT-PCR. Permeability assay was done by ussing chamber. The apoptotic cells were identified using an In Situ Cell Death Detection Kit. Protein was detected by western blot. Results: Probiotics can lower infection-related complications, as well as increase the serum and tissue let-7b levels. P38 MAPK was identified as the target of let-7b, as verified by NCM460 cells. P38 MAPK expression was increased, whereas tight-junction (TJ proteins were significantly decreased in let-7b IKO mice (both P<0.05. Negative regulation of p38 MAPK molecular signaling pathways was involved in the protective effects of let-7b on intestinal barrier function. Conclusion: Let-7b was identified as a novel diagnosis biomarker or a potential treatment target for preventing intestinal barrier dysfunction.

Protective Effects of Let-7b on the Expression of Occludin by Targeting P38 MAPK in Preventing Intestinal Barrier Dysfunction.

Science.gov (United States)

Liu, Zhihua; Tian, Yinghai; Jiang, Yanqiong; Chen, Shihua; Liu, Ting; Moyer, Mary Pat; Qin, Huanlong; Zhou, Xinke

2018-01-01

Let-7b was dramatically reduced after a dicer knockout of mice with intestinal barrier function injuries. This paper aims to investigate the molecular mechanism of let-7b by targeting p38 MAPK in preventing intestinal barrier dysfunction. A total of 186 patients were enrolled, with 93 in the control group and 93 in the PRO group. Only 158 patients completed the entire study, whereas the others either did not meet the inclusion criteria or refused to participate. To further verify the role of let-7b, intestinal epithelial conditional knockout (IKO) mice of mmu-let-7b model were established. Serum let-7b, zonulin, IL-6, and TNF-α concentrations were measured by ELISA or quantitative RT-PCR. Permeability assay was done by ussing chamber. The apoptotic cells were identified using an In Situ Cell Death Detection Kit. Protein was detected by western blot. Probiotics can lower infection-related complications, as well as increase the serum and tissue let-7b levels. P38 MAPK was identified as the target of let-7b, as verified by NCM460 cells. P38 MAPK expression was increased, whereas tight-junction (TJ) proteins were significantly decreased in let-7b IKO mice (both P<0.05). Negative regulation of p38 MAPK molecular signaling pathways was involved in the protective effects of let-7b on intestinal barrier function. Let-7b was identified as a novel diagnosis biomarker or a potential treatment target for preventing intestinal barrier dysfunction. © 2018 The Author(s). Published by S. Karger AG, Basel.

The TAM receptor Mertk protects against neuroinvasive viral infection by maintaining blood-brain barrier integrity.

Science.gov (United States)

Miner, Jonathan J; Daniels, Brian P; Shrestha, Bimmi; Proenca-Modena, Jose L; Lew, Erin D; Lazear, Helen M; Gorman, Matthew J; Lemke, Greg; Klein, Robyn S; Diamond, Michael S

2015-12-01

The TAM receptors Tyro3, Axl and Mertk are receptor tyrosine kinases that dampen host innate immune responses following engagement with their ligands Gas6 and Protein S, which recognize phosphatidylserine on apoptotic cells. In a form of apoptotic mimicry, many enveloped viruses display phosphatidylserine on the outer leaflet of their membranes, enabling TAM receptor activation and downregulation of antiviral responses. Accordingly, we hypothesized that a deficiency of TAM receptors would enhance antiviral responses and protect against viral infection. Unexpectedly, mice lacking Mertk and/or Axl, but not Tyro3, exhibited greater vulnerability to infection with neuroinvasive West Nile and La Crosse encephalitis viruses. This phenotype was associated with increased blood-brain barrier permeability, which enhanced virus entry into and infection of the brain. Activation of Mertk synergized with interferon-β to tighten cell junctions and prevent virus transit across brain microvascular endothelial cells. Because TAM receptors restrict pathogenesis of neuroinvasive viruses, these findings have implications for TAM antagonists that are currently in clinical development.

Response Time Analysis and Test of Protection System Instrument Channels for APR1400 and OPR1000

Energy Technology Data Exchange (ETDEWEB)

Lee, Chang Jae; Han, Seung; Yun, Jae Hee; Baek, Seung Min [Department of Instrumentation and Control System Engineering, KEPCO Engineering and Construction, Daejeon (Korea, Republic of); Lee, Sang Jeong [Department of Electronics Engineering, Chungnam National University, Daejeon (Korea, Republic of)

2015-07-01

Safety limits are required to maintain the integrity of physical barriers designed to prevent the uncontrolled release of radioactive materials in nuclear power plants. The safety analysis establishes two critical constraints that include an analytical limit in terms of a measured or calculated variable, and a specific time after the analytical limit is reached to begin protective action. Keeping with the nuclear regulations and industry standards, satisfying these two requirements will ensure that the safety limit will not be exceeded during the design basis event, either an anticipated operational occurrence or a postulated accident. Various studies on the setpoint determination methodology for the safety-related instrumentation have been actively performed to ensure that the requirement of the analytical limit is satisfied. In particular, the protection setpoint methodology for the advanced power reactor 1400 (APP1400) and the optimized power reactor 1000 (OPR1000) has been recently developed to cover both the design basis event and the beyond design basis event. The developed setpoint methodology has also been quantitatively validated using specific computer programs and setpoint calculations. However, the safety of nuclear power plants cannot be fully guaranteed by satisfying the requirement of the analytical limit. In spite of the response time verification requirements of nuclear regulations and industry standards, it is hard to find the studies on the systematically integrated methodology regarding the response time evaluation. In cases of APR1400 and OPR1000, the response time analysis for the plant protection system is partially included in the setpoint calculation and the response time test is separately performed via the specific plant procedure. The test technique has a drawback which is the difficulty to demonstrate completeness of timing test. The analysis technique has also a demerit of resulting in extreme times that not actually possible. Thus

Response Time Analysis and Test of Protection System Instrument Channels for APR1400 and OPR1000

International Nuclear Information System (INIS)

Lee, Chang Jae; Han, Seung; Yun, Jae Hee; Baek, Seung Min; Lee, Sang Jeong

2015-01-01

Safety limits are required to maintain the integrity of physical barriers designed to prevent the uncontrolled release of radioactive materials in nuclear power plants. The safety analysis establishes two critical constraints that include an analytical limit in terms of a measured or calculated variable, and a specific time after the analytical limit is reached to begin protective action. Keeping with the nuclear regulations and industry standards, satisfying these two requirements will ensure that the safety limit will not be exceeded during the design basis event, either an anticipated operational occurrence or a postulated accident. Various studies on the setpoint determination methodology for the safety-related instrumentation have been actively performed to ensure that the requirement of the analytical limit is satisfied. In particular, the protection setpoint methodology for the advanced power reactor 1400 (APP1400) and the optimized power reactor 1000 (OPR1000) has been recently developed to cover both the design basis event and the beyond design basis event. The developed setpoint methodology has also been quantitatively validated using specific computer programs and setpoint calculations. However, the safety of nuclear power plants cannot be fully guaranteed by satisfying the requirement of the analytical limit. In spite of the response time verification requirements of nuclear regulations and industry standards, it is hard to find the studies on the systematically integrated methodology regarding the response time evaluation. In cases of APR1400 and OPR1000, the response time analysis for the plant protection system is partially included in the setpoint calculation and the response time test is separately performed via the specific plant procedure. The test technique has a drawback which is the difficulty to demonstrate completeness of timing test. The analysis technique has also a demerit of resulting in extreme times that not actually possible. Thus

Nevada Test Site Radiation Protection Program - Revision 1

International Nuclear Information System (INIS)

Nevada Test Site Radiological Control Managers' Council

2008-01-01

Title 10 Code of Federal Regulations (CFR) Part 835, 'Occupational Radiation Protection,' establishes radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of U.S. Department of Energy (DOE) activities. 10 CFR 835.101(a) mandates that DOE activities be conducted in compliance with a documented Radiation Protection Program (RPP) as approved by DOE. This document promulgates the RPP for the Nevada Test Site (NTS), related (on-site or off-site) U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) operations, and environmental restoration off-site projects. This NTS RPP promulgates the radiation protection standards, limits, and program requirements for occupational exposure to ionizing radiation resulting from NNSA/NSO activities at the NTS and other operational areas as stated in 10 CFR 835.1(a). NNSA/NSO activities (including design, construction, operation, and decommissioning) within the scope of this RPP may result in occupational exposures to radiation or radioactive material. Therefore, a system of control is implemented through specific references to the site-specific NV/YMP RCM. This system of control is intended to ensure that the following criteria are met: (1) occupational exposures are maintained as low as reasonably achievable (ALARA), (2) DOE's limiting values are not exceeded, (3) employees are aware of and are prepared to cope with emergency conditions, and (4) employees are not inadvertently exposed to radiation or radioactive material

Nevada Test Site Radiation Protection Program - Revision 1

Energy Technology Data Exchange (ETDEWEB)

Radiological Control Managers' Council

2008-06-01

Title 10 Code of Federal Regulations (CFR) Part 835, 'Occupational Radiation Protection,' establishes radiation protection standards, limits, and program requirements for protecting individuals from ionizing radiation resulting from the conduct of U.S. Department of Energy (DOE) activities. 10 CFR 835.101(a) mandates that DOE activities be conducted in compliance with a documented Radiation Protection Program (RPP) as approved by DOE. This document promulgates the RPP for the Nevada Test Site (NTS), related (on-site or off-site) U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) operations, and environmental restoration off-site projects. This NTS RPP promulgates the radiation protection standards, limits, and program requirements for occupational exposure to ionizing radiation resulting from NNSA/NSO activities at the NTS and other operational areas as stated in 10 CFR 835.1(a). NNSA/NSO activities (including design, construction, operation, and decommissioning) within the scope of this RPP may result in occupational exposures to radiation or radioactive material. Therefore, a system of control is implemented through specific references to the site-specific NV/YMP RCM. This system of control is intended to ensure that the following criteria are met: (1) occupational exposures are maintained as low as reasonably achievable (ALARA), (2) DOE's limiting values are not exceeded, (3) employees are aware of and are prepared to cope with emergency conditions, and (4) employees are not inadvertently exposed to radiation or radioactive material.

Data processing for the evaluation of the thickness of protective barriers : Case of radiology rooms and external beam radiotherapy

International Nuclear Information System (INIS)

RANDRIANANTOANDRO, R.G.G.

2004-01-01

The regulation requires that the legal persons who have an intention to use radiation sources shall submit a notification to the Regulatory Authority of such an intention, which shall take the form of a licence or an authorization. The documents of radiological safety including design, construction, clinical utilisation...are attached to this notification. This work intends to assess the thickness of protection barrier and to suggest a facility design in radiology and in radiotherapy which comply with the safety standards. Because the steps of the thickness evaluation require a lot of calculation and abacs, the computer is used for this processing with Visual Basic. [fr

Skin Barrier Function and Allergens

DEFF Research Database (Denmark)

Engebretsen, Kristiane Aasen; Thyssen, Jacob Pontoppidan

2016-01-01

The skin is an important barrier protecting us from mechanical insults, microorganisms, chemicals and allergens, but, importantly, also reducing water loss. A common hallmark for many dermatoses is a compromised skin barrier function, and one could suspect an elevated risk of contact sensitization...... and skin barrier status. Psoriasis has traditionally been regarded a Th1-dominated disease, but the discovery of Th17 cells and IL-17 provides new and interesting information regarding the pathogenesis of the disease. Research suggests an inverse relationship between psoriasis and CA, possibly due......) and Th2 (AD) have been proposed as an explanation. Finally, there is convincing evidence that exposure to irritants increases the risk of CS, and patients with ICD are, therefore, at great risk of developing CA. Skin irritation leads to the release of IL-1 and TNF-α, which affects the function of antigen...

Mitigation of lava flow invasion hazard through optimized barrier configuration aided by numerical simulation: The case of the 2001 Etna eruption

Science.gov (United States)

Scifoni, S.; Coltelli, M.; Marsella, M.; Proietti, C.; Napoleoni, Q.; Vicari, A.; Del Negro, C.

2010-04-01

Lava flow spreading along the flanks of Etna volcano often produces damages to the land and proprieties. The impact of these eruptions could be mitigated by building artificial barriers for controlling and slowing down the lava, as recently experienced in 1983, 1991-1993, 2001 and 2002. This study investigates how numerical simulations can be adopted for evaluating the effectiveness of barrier construction and for optimizing their geometry, considering as test case the lava flows emplaced on Etna's south flank during 2001. The flow temporal evolutions were reconstructed deriving the effusion rate trends, together with the pre-eruption topography were adopted as input data of the MAGFLOW simulation code. Three simulations were then conducted to simulate lava flow with and without barriers. The first aimed at verifying the reconstruction of the effusion rate trends, while the others at assessing the performance of the barrier system realized during the eruption in comparison with an alternative solution here proposed. A quantitative analysis carried out on the first simulation confirms the suitability of the selected test case. The comparison of the three simulated thickness distributions showed both the effectiveness of the barriers in slowing down the lava flow and the sensitivity of the MAGFLOW code to the topographical variations represented by the barriers. Finally, for reducing both the time necessary to erect the barrier and the barrier environmental impact, the gabion's barrier construction was analyzed. The implemented and tested procedure enforces the capability of using numerical simulations for designing optimized lava flow barriers aimed at making swifter mitigatory actions upon lava flows and improving the effectiveness of civil protection interventions during emergencies.

The Effects of information barrier requirements on the trilateral initiative attribute measurement system (AVNG)

International Nuclear Information System (INIS)

MacArthur, D.W.; Langner, D.C.; Whiteson, R.; Wolford, J.K.

2001-01-01

Although the detection techniques used for measuring classified materials are very similar to those used in unclassified measurements, the surrounding packaging is generally very different. If iZ classified item is to be measured, an information barrier is required to protect any classified data acquired. This information barrier must protect the classified information while giving the inspector confidence that the unclassified outputs accurately reflect the classified inputs, Both information barrier and authentication considerations must be considered during all phases of system design and fabrication. One example of such a measurement system is the attribute measurement system (termed the AVNG) designed for the: Trilateral Initiative. We will discuss the integration of information barrier components into this system as well as the effects of an information barrier (including authentication) concerns on the implementation of the detector systems.

Glucagon-like peptide-2 protects impaired intestinal mucosal barriers in obstructive jaundice rats.

Science.gov (United States)

Chen, Jun; Dong, Jia-Tian; Li, Xiao-Jing; Gu, Ye; Cheng, Zhi-Jian; Cai, Yuan-Kun

2015-01-14

To observe the protective effect of glucagon-like peptide-2 (GLP-2) on the intestinal barrier of rats with obstructive jaundice and determine the possible mechanisms of action involved in the protective effect. Thirty-six Sprague-Dawley rats were randomly divided into a sham operation group, an obstructive jaundice group, and a GLP-2 group; each group consisted of 12 rats. The GLP-2 group was treated with GLP-2 after the day of surgery, whereas the other two groups were treated with the same concentration of normal saline. Alanine aminotransferase (ALT), total bilirubin, and endotoxin levels were recorded at 1, 3, 7, 10 and 14 d. Furthermore, on the 14(th) day, body weight, the wet weight of the small intestine, pathological changes of the small intestine and the immunoglobulin A (IgA) expressed by plasma cells located in the small intestinal lamina propria were recorded for each group. In the rat model, jaundice was obvious, and the rats' activity decreased 4-6 d post bile duct ligation. Compared with the sham operation group, the obstructive jaundice group displayed increased yellow staining of abdominal visceral serosa, decreased small intestine wet weight, thinning of the intestinal muscle layer and villi, villous atrophy, uneven height, fusion, partial villous epithelial cell shedding, substantial inflammatory cell infiltration and significantly reduced IgA expression. However, no significant gross changes were noted between the GLP-2 and sham groups. With time, the levels of ALT, endotoxin and bilirubin in the GLP-2 group were significantly increased compared with the sham group (P jaundice group than in the GLP-2 group (P jaundice rats, which might be attributed to increased intestinal IgA and reduced bilirubin and endotoxin.

Barriers and facilitators to HIV testing among young men who have sex with men and transgender women in Kingston, Jamaica: a qualitative study.

Science.gov (United States)

Logie, Carmen H; Lacombe-Duncan, Ashley; Brien, Natasha; Jones, Nicolette; Lee-Foon, Nakia; Levermore, Kandasi; Marshall, Annecka; Nyblade, Laura; Newman, Peter A

2017-04-04

Young men who have sex with men (MSM) in Jamaica have the highest HIV prevalence in the Caribbean. There is little information about HIV among transgender women in Jamaica, who are also overrepresented in the Caribbean epidemic. HIV-related stigma is a barrier to HIV testing among Jamaica's general population, yet little is known of MSM and transgender women's HIV testing experiences in Jamaica. We explored perceived barriers and facilitators to HIV testing among young MSM and transgender women in Kingston, Jamaica. We implemented a community-based research project in collaboration with HIV and lesbian, gay, bisexual and transgender (LGBT) agencies in Kingston. We held two focus groups, one with young (aged 18-30 years) transgender women (n = 8) and one with young MSM (n = 10). We conducted 53 in-depth individual semi-structured interviews focused on HIV testing experiences with young MSM (n = 20), transgender women (n = 20), and community-based key informants (n = 13). We conducted thematic analysis to identify, analyze, and report themes. Participant narratives revealed social-ecological barriers and facilitators to HIV testing. Barriers included healthcare provider mistreatment, confidentiality breaches, and HIV-related stigma: these spanned interpersonal, community and structural levels. Healthcare provider discrimination and judgment in HIV testing provision presented barriers to accessing HIV services (e.g. treatment), and resulted in participants hiding their sexual orientation and/or gender identity. Confidentiality concerns included: clinic physical arrangements that segregated HIV testing from other health services, fear that healthcare providers would publicly disclose their status, and concerns at LGBT-friendly clinics that peers would discover they were getting tested. HIV-related stigma contributed to fear of testing HIV-positive; this intersected with the stigma of HIV as a "gay" disease. Participants also anticipated healthcare provider

Biodiversity of the Great Barrier Reef—how adequately is it protected?

Directory of Open Access Journals (Sweden)

Zoe T. Richards

2018-05-01

Full Text Available Background The Great Barrier Reef (GBR is the world’s most iconic coral reef ecosystem, recognised internationally as a World Heritage Area of outstanding significance. Safeguarding the biodiversity of this universally important reef is a core legislative objective; however, ongoing cumulative impacts including widespread coral bleaching and other detrimental impacts have heightened conservation concerns for the future of the GBR. Methods Here we review the literature to report on processes threatening species on the GBR, the status of marine biodiversity, and evaluate the extent of species-level monitoring and reporting. We assess how many species are listed as threatened at a global scale and explore whether these same species are protected under national threatened species legislation. We conclude this review by providing future directions for protecting potentially endangered elements of biodiversity within the GBR. Results Most of the threats identified to be harming the diversity of marine life on the GBR over the last two–three decades remain to be effectively addressed and many are worsening. The inherent resilience of this globally significant coral reef ecosystem has been seriously compromised and various elements of the biological diversity for which it is renowned may be at risk of silent extinction. We show at least 136 of the 12,000+ animal species known to occur on the GBR (approximately 20% of the 700 species assessed by the IUCN occur in elevated categories of threat (Critically Endangered, Endangered or Vulnerable at a global scale. Despite the wider background level of threat for these 136 species, only 23 of them are listed as threatened under regional or national legislation. Discussion To adequately protect the biodiversity values of the GBR, it may be necessary to conduct further targeted species-level monitoring and reporting to complement ecosystem management approaches. Conducting a vigorous value of information

Advanced house air-barrier systems

Energy Technology Data Exchange (ETDEWEB)

Lee, R.K. [Natural Resources Canada, Ottawa, ON (Canada)

1996-08-01

Air barrier systems used in modern Canadian airtight homes were discussed. The Advanced Houses Program sets its airtightness requirements at 1.5 air changes per hour at 50 Pascals pressure difference (ACH{sub 5}0). In recent tests of 10 houses, it was suggested that a better airtightness level was attainable with average airtightness of about 1.0 ACH{sub 5}0. Six of the homes tested did not use the traditional polyethylene approach. Two of the houses used the airtight drywall approach, one used a foam system, and three used exterior air barriers. The advantages and disadvantages of each system was described, including cost effectiveness, cost reduction, performance and installation advantages. The confusion between an air barrier and a vapour diffusion retarder was explained. Exterior air barriers showed the greatest potential for meeting airtightness requirements at reasonable cost. 5 refs., 3 tabs.

Are squash players protecting their eyes?

Science.gov (United States)

Eime, R M; Finch, C F; Sherman, C A; Garnham, A P

2002-09-01

To determine factors associated with adult squash players' protective eyewear behaviours. A survey of 303 players (aged >or =18 years) was conducted at three squash venues in Melbourne, Australia over a three week period in June 2000 to obtain information about protective eyewear use. Of 303 participants the response rate was 98.1%; 66.1% were males, with a mean age of 40.5 years. The majority (68.4%) had played squash for 10 years or more. Although 18.8% of players reported using protective eyewear, only 8.9% reported wearing approved eyewear. Both age group (peye injuries (50.0%) and knowledge of eye injury risk (33.9%). A commonly reported barrier was restriction of vision (34.2%). These findings demonstrate a low prevalence of voluntary use of appropriate protective eyewear. Future prevention strategies incorporating education campaigns should focus on increasing players' knowledge of risks. The barriers to use and misconceptions about which types of eyewear is most protective need to be addressed as a priority.

Low utilization of HIV testing during pregnancy: What are the barriers to HIV testing for women in rural India?

Science.gov (United States)

Sinha, Gita; Dyalchand, Ashok; Khale, Manisha; Kulkarni, Gopal; Vasudevan, Shubha; Bollinger, Robert C

2008-02-01

Sixty percent of India's HIV cases occur in rural residents. Despite government policy to expand antenatal HIV screening and prevention of maternal-to-child transmission (PMTCT), little is known about HIV testing among rural women during pregnancy. Between January and March 2006, a cross-sectional sample of 400 recently pregnant women from rural Maharashtra was administered a questionnaire regarding HIV awareness, risk, and history of antenatal HIV testing. Thirteen women (3.3%) reported receiving antenatal HIV testing. Neither antenatal care utilization nor history of sexually transmitted infection (STI) symptoms influenced odds of receiving HIV testing. Women who did not receive HIV testing, compared with women who did, were 95% less likely to have received antenatal HIV counseling (odds ratio = 0.05, 95% confidence interval: 0.02 to 0.17) and 80% less aware of an existing HIV testing facility (odds ratio = 0.19, 95% confidence interval: 0.04 to 0.75). Despite measurable HIV prevalence, high antenatal care utilization, and STI symptom history, recently pregnant rural Indian women report low HIV testing. Barriers to HIV testing during pregnancy include lack of discussion by antenatal care providers and lack of awareness of existing testing services. Provider-initiated HIV counseling and testing during pregnancy would optimize HIV prevention for women throughout rural India.

Eye dosimetry and protective eye wear for interventional clinicians

International Nuclear Information System (INIS)

Martin, C.J.; Magee, J.S.; Sandblom; Almen, A.; Lundh, C.

2015-01-01

Doses to the eyes of interventional clinicians can exceed 20 mSv. Various protective devices can afford protection to the eyes with the final barrier being protective eye wear. The protection provided by lead glasses is difficult to quantify, and the majority of dosimeters are not designed to be worn under lead glasses. This study has measured dose reduction factors (DRFs) equal to the ratio of the dose with no protection, divided by that when lead glasses are worn. Glasses have been tested in X-ray fields using anthropomorphic phantoms to simulate the patient and clinician. DRFs for X-rays incident from the front vary from 5.2 to 7.6, while values for orientations reminiscent of clinical practice are between 1.4 and 5.2. Results suggest that a DRF of two is a conservative factor that could be applied to personal dosimeter measurements to account for the dose reduction provided by most types of lead glasses. (authors)

Evaluation of Subsurface Engineered Barriers at Waste Sites Volumes 1 and 2

Science.gov (United States)

This report provides the U.S. Environmental Protection Agency’s (EPA) waste programs with a national retrospective analysis of barrier field performance, as well as information that useful in developing guidance on the use and evaluation of barrier systems

Design and testing of integrated circuits for reactor protection channels

International Nuclear Information System (INIS)

Battle, R.E.; Vandermolen, R.I.; Jagadish, U.; Swail, B.K.; Naser, J.; Rana, I.

1995-01-01

Custom and semicustom application-specific integrated circuit design and testing methods are investigated for use in research and commercial nuclear reactor safety systems. The Electric Power Research Institute and Oak Ridge National Laboratory are working together through a cooperative research and development agreement to apply modern technology to a nuclear reactor protection system. Purpose of this project is to demonstrate to the nuclear industry an alternative approach for new or upgrade reactor protection and safety system signal processing and voting logic. Motivation for this project stems from (1) the difficulty of proving that software-based protection systems are adequately reliable, (2) the obsolescence of the original equipment, and (3) the improved performance of digital processing

Summary of activities at the Engineered Barriers Test Facility, October 1, 1995 to January 31, 1997, and initial data

International Nuclear Information System (INIS)

Porro, I.; Keck, K.N.

1997-03-01

Replicates of two engineered barrier designs (a thick soil barrier and a bio/capillary barrier) were constructed in the test plots of the facility. Prior to placement of any soil in the test plots, instruments were calibrated and attached to plot instrument towers, which were then installed in the test plots. Soil from Spreading Area B was installed in the test plots in lifts and compacted. Instruments attached to the instrument tower were placed in shallow trenches dug in the lifts and buried. Each instrument was checked to make sure it functioned prior to installation of the next lift. Soil samples were collected from each lift in one plot during construction for later determination of physical and hydraulic properties. After completion of the test plots, the data acquisition system was finalized, and data collection began. Appropriate instrument calibration equations and equation coefficients are presented, and data reduction techniques are described. Initial data show test plot soils drying throughout the summer and early fall. This corresponds to low rainfall during this period. Infiltration of water into the test plots was first detected around mid-November with several subsequent episodes in December. Infiltration was verified by corresponding measurements from several different instruments ime domain reflectometry (TDR), neutron probe, thermocouple psychrometers, and heat dissipation sensors Tensiometer data does not appear to corroborate data from the other instruments. Test plots were warmer on the side closest to the access trench indicating a temperature effect from the trench. This resulted in greater soil moisture freezing with less and shallower infiltration on the far side of the plots than on the side closest to the trench. At the end of this monitoring period, infiltration in all but two of the test plots has reached the 155-cm depth. Infiltration in test plots B2 and S3 has reached only the 140-cm depth. The monitored infiltration events have not

The relative importance of patient-reported barriers to colorectal cancer screening.

Science.gov (United States)

Jones, Resa M; Woolf, Steven H; Cunningham, Tina D; Johnson, Robert E; Krist, Alex H; Rothemich, Stephen F; Vernon, Sally W

2010-05-01

Colorectal cancer (CRC) screening rates are suboptimal. The most important barriers identified by patients are poorly understood. A comprehensive assessment of barriers to all recommended modalities is needed. In 2007, a questionnaire was mailed to 6100 patients, aged 50-75 years, from 12 family medicine practices in the Virginia Ambulatory Care Outcomes Research Network. People aged 65-75 years and African Americans were oversampled. Patients were asked to rate 19-21 barriers to each of four recommended tests. In 2008, responses were coded on a 5-point scale; higher scores reflected stronger barrier endorsement. The response rate was 55% (n=3357). Approximately 40% of respondents were aged >/=65 years, 30% were African-American, and 73% were adherent to screening. A clinician's failure to suggest screening and not knowing testing was necessary received the highest mean scores as barriers. Financial concerns and misconceptions were also cited. Barrier scores differed depending on whether respondents were never screened, overdue for screening, or adherent to guidelines. The top five barriers for each modality included test-specific barriers (e.g., handling stool, bowel preparation), which often outranked generic barriers to screening. Not knowing testing was necessary was a top barrier for all tests but colonoscopy. Although physician advice and awareness of the need for screening are important, barriers to screening are not homogenous across tests, and test-specific barriers warrant consideration in designing strategies to improve screening rates. Barrier scores differ by screening status, highlighting the need to address prior screening experience. Evidence that patients are more familiar with colonoscopy than with other modalities suggests an opportunity to improve screening rates by educating patients about alternative tests. 2010 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Advanced Environmental Barrier Coating Development for SiC/SiC Ceramic Matrix Composites: NASA's Perspectives

Science.gov (United States)

Zhu, Dongming

2016-01-01

This presentation reviews NASA environmental barrier coating (EBC) system development programs and the coating materials evolutions for protecting the SiC/SiC Ceramic Matrix Composites in order to meet the next generation engine performance requirements. The presentation focuses on several generations of NASA EBC systems, EBC-CMC component system technologies for SiC/SiC ceramic matrix composite combustors and turbine airfoils, highlighting the temperature capability and durability improvements in simulated engine high heat flux, high pressure, high velocity, and with mechanical creep and fatigue loading conditions. The current EBC development emphasis is placed on advanced NASA 2700F candidate environmental barrier coating systems for SiC/SiC CMCs, their performance benefits and design limitations in long-term operation and combustion environments. Major technical barriers in developing environmental barrier coating systems, the coating integrations with next generation CMCs having the improved environmental stability, erosion-impact resistance, and long-term fatigue-environment system durability performance are described. The research and development opportunities for advanced turbine airfoil environmental barrier coating systems by utilizing improved compositions, state-of-the-art processing methods, and simulated environment testing and durability modeling are discussed.

Creation and validation of the barriers to alcohol reduction (BAR) scale using classical test theory and item response theory.

Science.gov (United States)

Kunicki, Zachary J; Schick, Melissa R; Spillane, Nichea S; Harlow, Lisa L

2018-06-01

Those who binge drink are at increased risk for alcohol-related consequences when compared to non-binge drinkers. Research shows individuals may face barriers to reducing their drinking behavior, but few measures exist to assess these barriers. This study created and validated the Barriers to Alcohol Reduction (BAR) scale. Participants were college students ( n  = 230) who endorsed at least one instance of past-month binge drinking (4+ drinks for women or 5+ drinks for men). Using classical test theory, exploratory structural equation modeling found a two-factor structure of personal/psychosocial barriers and perceived program barriers. The sub-factors, and full scale had reasonable internal consistency (i.e., coefficient omega = 0.78 (personal/psychosocial), 0.82 (program barriers), and 0.83 (full measure)). The BAR also showed evidence for convergent validity with the Brief Young Adult Alcohol Consequences Questionnaire ( r  = 0.39, p  Theory (IRT) analysis showed the two factors separately met the unidimensionality assumption, and provided further evidence for severity of the items on the two factors. Results suggest that the BAR measure appears reliable and valid for use in an undergraduate student population of binge drinkers. Future studies may want to re-examine this measure in a more diverse sample.

Thermal Protection Test Bed Pathfinder Development Project

Science.gov (United States)

Snapp, Cooper

2015-01-01

In order to increase thermal protection capabilities for future reentry vehicles, a method to obtain relevant test data is required. Although arc jet testing can be used to obtain some data on materials, the best method to obtain these data is to actually expose them to an atmospheric reentry. The overprediction of the Orion EFT-1 flight data is an example of how the ground test to flight traceability is not fully understood. The RED-Data small reentry capsule developed by Terminal Velocity Aerospace is critical to understanding this traceability. In order to begin to utilize this technology, ES3 needs to be ready to build and integrate heat shields onto the RED-Data vehicle. Using a heritage Shuttle tile material for the heat shield will both allow valuable insight into the environment that the RED-Data vehicle can provide and give ES3 the knowledge and capability to build and integrate future heat shields for this vehicle.

Unsaturated zone moisture and vapor movement induced by temperature variations in asphalt barrier field lysimeters

International Nuclear Information System (INIS)

Holford, D.J.; Fayer, M.J.

1990-08-01

Protective barriers are being considered for use at the Hanford Site to enhance the isolation of radioactive wastes from water, plant, and animal intrusion. Lysimeters were constructed to evaluate the performance of asphalt barrier formulations under natural environmental conditions. These lysimeters were constructed of 1.7-m lengths of PVC pipe that have a diameter of 30 cm. The lysimeters were filled with layers of gravel, coarse sand, and asphalt. The sand and gravel placed under the asphalt barrier were wet when installed. TOUGH was used to conduct simulations to assess the effect of temperature variations on moisture and vapor movement beneath the asphalt layer in field test lysimeters. All variables in TOUGH were converted to double precision so that simulations could be run on a Sun-4 UNIX workstation. A radially symmetric grid was used to simulate the lysimeter. 8 refs., 9 figs

Tritium/hydrogen barrier development

International Nuclear Information System (INIS)

Hollenberg, G.W.; Simonen, E.P.; Kalinen, G.; Terlain, A.

1994-06-01

A review of hydrogen permeation barriers that can be applied to structural metals used in fusion power plants is presented. Both implanted and chemically available hydrogen isotopes must be controlled in fusion plants. The need for permeation barriers appears strongest in Li17-Pb blanket designs, although barriers also appear necessary for other blanket and coolant systems. Barriers that provide greater than a 1000 fold reduction in the permeation of structural metals are desired. In laboratory experiments, aluminide and titanium ceramic coatings provide permeation reduction factors, PRFS, from 1000 to over 100,000 with a wide range of scatter. The rate-controlling mechanism for hydrogen permeation through these barriers may be related to the number and type of defects in the barriers. Although these barriers appear robust and resistant to liquid metal corrosion, irradiation tests which simulate blanket environments result in very low PRFs in comparison to laboratory experiments, i.e., <150. It is anticipated from fundamental research activities that the REID enhancement of hydrogen diffusion in oxides may contribute to the lower permeation reduction factors during in-reactor experiments

MODELING OF POWER SYSTEMS AND TESTING OF RELAY PROTECTION DEVICES IN REAL AND MODEL TIME

Directory of Open Access Journals (Sweden)

I. V. Novash

2017-01-01

Full Text Available The methods of modelling of power system modes and of testing of relay protection devices with the aid the simulation complexes in real time and with the help of computer software systems that enables the simulation of virtual time scale are considered. Information input protection signals in the simulation of the virtual model time are being obtained in the computational experiment, whereas the tests of protective devices are carried out with the help of hardware and software test systems with the use of estimated input signals. Study of power system stability when modes of generating and consuming electrical equipment and conditions of devices of relay protection are being changed requires testing with the use of digital simulators in a mode of a closed loop. Herewith feedbacks between a model of the power system operating in a real time and external devices or their models must be determined (modelled. Modelling in real time and the analysis of international experience in the use of digital simulation power systems for real-time simulation (RTDS simulator have been fulfilled. Examples are given of the use of RTDS systems by foreign energy companies to test relay protection systems and control, to test the equipment and devices of automatic control, analysis of cyber security and evaluation of the operation of energy systems under different scenarios of occurrence of emergency situations. Some quantitative data on the distribution of RTDS in different countries and Russia are presented. It is noted that the leading energy universities of Russia use the real-time simulation not only to solve scientific and technical problems, but also to conduct training and laboratory classes on modelling of electric networks and anti-emergency automatic equipment with the students. In order to check serviceability of devices of relay protection without taking into account the reaction of the power system tests can be performed in an open loop mode with the

Noninvasive evaluation of the barrier properties of the skin

Directory of Open Access Journals (Sweden)

Utz S.R.

2014-09-01

Full Text Available Skin as an organ of protection covers the body and accomplishes multiple defensive functions. The intact skin represents a barrier to the uncontrolled loss of water, proteins, and plasma components from the organism. Due to its complex structure, the epidermal barrier with its major component, stratum corneum, is the rate-limiting unit for the penetration of exogenous substances through the skin. The epidermal barrier is not a static structure. The permeability barrier status can be modified by different external and internal factors such as climate, physical stressors, and a number of skin and systemic diseases. Today, different non-invasive approaches are used to monitor the skin barrier physical properties in vivo. The quantification of parameters such as transepidermal water loss, stratum corneum hydration, and skin surface acidity is essential for the integral evaluation of the epidermal barrier status. This paper will allow the readership to get acquainted with the non-invasive, in vivo methods for the investigation of the skin barrier.

Testing and Labelling of Sun Protective Clothing for Children

International Nuclear Information System (INIS)

Clifton, R.

2000-01-01

In recent years, there has been increasing interest shown in the protective properties of clothing against the harmful effects of UV radiation from the sun. The incidence of skin cancer has been rising in many parts of the world, but especially in Australia and northern Europe. This is due to a number of factors including changing lifestyles, perceptions of the 'tanned image' and ozone depletion. Initial research was carried out in Australia where a test method for fabrics was formulated with a classification procedure. A number of European countries have taken up this initiative including the UK which earlier last year produced their own test method - BS 7914:1998. The European Union are now in the final stages of formulating the test method to be used by all member countries. Further work has also been carried out by BSI to investigate the complex aspects of labelling criteria in respect of garments. This has culminated in the recent publication (i.e. July 1999) of another standard - BS 7949:1999 - entitled 'Children's Clothing Requirements for Protection against Erythemally Weighted Solar Ultraviolet Radiation'. Other, more difficult parameters not yet covered in any of the published standards are still to be evaluated. These include the changes in the sun protection properties of textiles in a wet and/or stretched condition (precisely the state of many garments worn in the sun) and the requirements for products such as sun-shades and parasols where the measurement of UV reflectance is also very relevant. This current situation is reviewed and those aspects highlighted where resources for investigative research are needed, particularly by textile manufacturers and retailers. (author)

Near-Surface Engineered Environmental Barrier Integrity

International Nuclear Information System (INIS)

Piet, S.J.; Breckenridge, R.P.

2002-01-01

The INEEL Environmental Systems Research and Analysis (ESRA) program has launched a new R and D project on Near-Surface Engineered Environmental Barrier Integrity to increase knowledge and capabilities for using engineering and ecological components to improve the integrity of near-surface barriers used to confine contaminants from the public and the environment. The knowledge gained and the capabilities built will help verify the adequacy of past remedial decisions and enable improved solutions for future cleanup decisions. The research is planned to (a) improve the knowledge of degradation mechanisms (weathering, biological, geological, chemical, radiological, and catastrophic) in times shorter than service life, (b) improve modeling of barrier degradation dynamics, (c) develop sensor systems to identify degradation prior to failure, and (d) provide a better basis for developing and testing of new barrier systems to increase reliability and reduce the risk of failure. Our project combine s selected exploratory studies (benchtop and field scale), coupled effects accelerated aging testing and the meso-scale, testing of new monitoring concepts, and modeling of dynamic systems. The performance of evapo-transpiration, capillary, and grout-based barriers will be examined

Protection against malevolent use of vehicles at Nuclear Power Plants. Vehicle barrier system siting guidance for blast protection

International Nuclear Information System (INIS)

Nebuda, D.T.

1994-08-01

This manual provides guidance for determining the minimum safe standoff distance between vital safety related equipment and the design basis vehicle bomb threat adopted by the U.S. Nuclear Regulatory Commission. Vital safety related equipment should survive the design basis vehicle bomb attack when the minimum safe standoff distance is provided. Guidance is provided for exposed vital safety related equipment and for equipment housed within vital area barriers. The type of vital area barriers addressed are 12-, 18-, 24-, and 30-inch-thick reinforced concrete slabs with reinforcing ratios of 0.2, 0.4, 0.6, 0.8, and 1.0 percent

Long-Term Climate Change Assessment Task for the Hanford Site Permanent Isolation Barrier Development Program: Status through FY 1992

Energy Technology Data Exchange (ETDEWEB)

Petersen, K.L. [Westinghouse Hanford Co., Richland, WA (US); Chatters, J.C. [Pacific Northwest Lab., Richland, WA (US)

1993-07-01

The Hanford Site Permanent Isolation Barrier Development Program (Barrier Development Program) was organized (Adams and Wing 1986) to develop the technology needed to provide an in-place disposal capability for the US Department of Energy at the Hanford Site in southeastern Washington. The goals of the Barrier Development Program are to provide defensible evidence that final barrier design(s) will adequately control water infiltration, plant and animal intrusion, and wind and water erosion for a minimum of 1,000 years; to isolate wastes from the accessible environment; and to use markers to warn inadvertent human intruders. Evidence for barrier performance will be obtained by conducting laboratory experiments, field tests, computer modeling, and other studies that establish confidence in the barrier`s ability to meet its 1,000-year design life. The performance and stability of natural barrier analogs that have existed for several millennia and the reconstruction of climate changes during the past 10,000 to 125,000 years also will provide insight into bounding conditions of possible future changes and increase confidence in the barriers design. In the following discussion the term {open_quotes}long-term{close_quotes} references periods of time up to 1000`s of years, distinguishing it from {open_quotes}short-term{close_quotes} weather patterns covering a decade or less. Specific activities focus on planning and conducting a series of studies and tests required to confirm key aspects of the barrier design. The effort is a collaborative one between scientists and engineers from Westinghouse Hanford Company (Westinghouse Hanford) and Pacific Northwest Laboratory (PNL) to design barriers to limit movement of radionuclides and other contaminants to the accessible environment for at least 1,000 years. These activities have been divided into 14 groups of tasks that aid in the complete development of protective barrier and warning marker system.

Barrier Island Dynamics Using Mass Center Analysis: A New Way to Detect and Track Large-Scale Change

Directory of Open Access Journals (Sweden)

Paul Paris

2014-01-01

Full Text Available A geographic information system (GIS was used to introduce and test a new method for quantitatively characterizing topographic change. Borrowing from classic Newtonian mechanics, the concept of a body’s center of mass is applied to the geomorphic landscape, and the barrier island environment in particular, to evaluate the metric’s potential as a proxy for detecting, tracking and visualizing change. Two barrier islands along North Carolina’s Outer Banks are used to test this idea: Core Banks, uninhabited and largely-undeveloped, and Hatteras Island, altered by the presence of a protective dune system. Findings indicate that for Core Banks, the alongshore change in the center of mass is in accord with dominate littoral transport and wind conditions. Cross-shore change agrees with independent estimates for the island migration rates. This lends credence to our assertion that the mass center metric has the potential to be a viable proxy for describing wholesale barrier migration and would be a valuable addition to the already-established ocean shoreline and subaerial volume metrics. More research is, however, required to demonstrate efficacy.

Radiation protection type testing and licensing of diagnostic X-ray equipment in the GDR

International Nuclear Information System (INIS)

Taschner, P.; Poulheim, K.F.; Feldheim, W.

1987-01-01

The results of more than 10 years experience in type testing and type licensing of diagnostic X-ray equipment with respect to meeting radiation protection requirements as well as the implications for the conduct of these procedures resulting from the introduction of new radiation protection legislation in 1983 and 1984, are described. At present an updated version of the 'Regulation of 16 December 1977 concerning radiation protection type testing and licensing of sealed radiation sources and equipment emitting ionizing radiation' is being prepared. (author)

Barrierer i lægesamtalen med indvandrerpatienten

DEFF Research Database (Denmark)

Sodemann, Morten; Rønde Kristensen, Trine; Sångren, Henrik

2015-01-01

misforståelser af klinisk betydning. Barriers to communication between clinicians and immigrants Clinicians lack cultural competencies and communication skills relevant to clinical decision-making in cases of language and cultural barriers. Life course perspectives and basic understanding of life in exile...... are not integrated in diagnostics, treatment or follow-up resulting in low patient compliance, mistrust, complications, diagnostic errors and delays. Stereotyping and generalizations put patients in a position where they are forced to protect themselves by withholding important information. When in doubt clinicians...

Environmental Barrier Coatings for Ceramic Matrix Composites - An Overview

Science.gov (United States)

Lee, Kang; van Roode, Mark; Kashyap, Tania; Zhu, Dongming; Wiesner, Valerie

2017-01-01

SiC/SiC Ceramic Matrix Composites (CMCs) are increasingly being considered as structural materials for advanced power generation equipment because of their light weight, higher temperature capability, and oxidation resistance. Limitations of SiC/SiC CMCs include surface recession and component cracking and associated chemical changes in the CMC. The solutions pursued to improve the life of SiC/SiC CMCs include the incorporation of coating systems that provide surface protection, which has become known as an Environmental Barrier Coating (EBC). The development of EBCs for the protection of gas turbine hot section CMC components was a continuation of coating development work for corrosion protection of silicon-based monolithics. Work on EBC development for SiC/SiC CMCs has been ongoing at several national laboratories and the original gas turbine equipment manufacturers. The work includes extensive laboratory, rig and engine testing, including testing of EBC coated SiC/SiC CMCs in actual field applications. Another EBC degradation issue which is especially critical for CMC components used in aircraft engines is the degradation from glassy deposits of calcium-magnesium-aluminosilicate (CMAS) with other minor oxides. This paper addresses the need for and properties of external coatings on SiC/SiC CMCs to extend their useful life in service and the retention of their properties.

Hanford prototype-barrier status report: FY 1997

International Nuclear Information System (INIS)

Ward, A.L.; Gee, G.W.; Link, S.O.

1997-12-01

An above-grade surface barrier consisting of a vegetated soil-cover, surrounded by gravel and rock side slopes, is being tested for the US Department of Energy (DOE). It is part of a treatability study at the 200-BP-1 Operable Unit in the 200 East Area of the Hanford Site, near Richland, Washington. The surface barrier, constructed in 1994, covers 2.5 ha (6.9 acre) of land surface and is situated over an inactive liquid-waste disposal crib. A set of under drains, built into the barrier using curbed asphalt, allows precise measurement of drainage from the soil cover and the side slopes. The treatability test includes measurements of water balance, wind and water erosion, subsidence, plant growth, and plant and animal intrusion. The test compares the performance of the barrier under ambient and simulated climate change (elevated precipitation) conditions. This report documents findings from the third year of testing

Barrier design for tornado-generated missiles

International Nuclear Information System (INIS)

Kar, A.K.

1977-01-01

Nuclear power plant facilities and many other structures need protection against missiles generated by tornados and explosions. The missile impacts result in both local and overall effects on barriers or targets. The local effects are characterized by penetration, perforation and backface spalling or scabbing of the target material. The overall effects of missile impact on structural stability are commonly evaluated in terms of the flexural and shear behaviour of the target. Empirical formulas are presented to determine the local effects on concrete and steel barriers. Procedures are given for determining the design loads for overall effects. Design methods are described. (Auth.)

Permanent isolation surface barrier: Functional performance

International Nuclear Information System (INIS)

Wing, N.R.

1993-10-01

This document presents the functional performance parameters for permanent isolation surface barriers. Permanent isolation surface barriers have been proposed for use at the Hanford Site (and elsewhere) to isolate and dispose of certain types of waste in place. Much of the waste that would be disposed of using in-place isolation techniques is located in subsurface structures, such as solid waste burial grounds, tanks, vaults, and cribs. Unless protected in some way, the wastes could be transported to the accessible environment via transport pathways, such as water infiltration, biointrusion, wind and water erosion, human interference, and/or gaseous release

Barrier design for tornado-generated missiles

International Nuclear Information System (INIS)

Kar, A.K.

1977-01-01

Nuclear powerplant facilities and many other structures need protection against missiles generated by tornadoes and explosions. The missile impacts result in both local and overall effects on barriers or targets. The local effects are characterized by penetration, perforation, and backface spalling or scabbing of the target material. The overall effects of missile impact on structural stability are commonly evaluated in terms of the flexural and shear behavior of the target. Empirical formulas are presented to determine the local effects on concrete and steel barriers. Procedures are given for determining the design loads for overall effects. Design methods are described

Evaluation of the protection factor of half-masks with respirator fitting test apparatus

International Nuclear Information System (INIS)

Murata, M.; Ikezawa, Y.; Yoshida, Y.; Matsui, H.; Kokubu, M.

1980-01-01

A respirator fitting test apparatus has been developed to select half-masks of high performance and to estimate their protective ability. With the apparatus, the facepiece leakage was measured for six different half-masks worn by 40 volunteer subjects, under simulated working conditions of normal breathing, smiling, moving head, and talking. A cloud of submicron sodium chloride particles was fed into a test hood in which the subject wore a mask. The air sampled from inside the mask with a miniature pump was assessed by a flame photometer. It is hown that the protection factor (ratio of the concentration of test cloud outside the mask to that inside) for each mask varies widely with the subject and the working conditions, and that the protection factors roughly fit a lognormal distribution. The values characterizing the distributions of respective masks are given. (H.K.)

Assessing community values for reducing agricultural emissions to improve water quality and protect coral health in the Great Barrier Reef

Science.gov (United States)

Rolfe, John; Windle, Jill

2011-12-01

Policymakers wanting to increase protection of the Great Barrier Reef from pollutants generated by agriculture need to identify when measures to improve water quality generate benefits to society that outweigh the costs involved. The research reported in this paper makes a contribution in several ways. First, it uses the improved science understanding about the links between management changes and reef health to bring together the analysis of costs and benefits of marginal changes, helping to demonstrate the appropriate way of addressing policy questions relating to reef protection. Second, it uses the scientific relationships to frame a choice experiment to value the benefits of improved reef health, with the results of mixed logit (random parameter) models linking improvements explicitly to changes in "water quality units." Third, the research demonstrates how protection values are consistent across a broader population, with some limited evidence of distance effects. Fourth, the information on marginal costs and benefits that are reported provide policymakers with information to help improve management decisions. The results indicate that while there is potential for water quality improvements to generate net benefits, high cost water quality improvements are generally uneconomic. A major policy implication is that cost thresholds for key pollutants should be set to avoid more expensive water quality proposals being selected.

Rheological and sensory properties of hydrophilic skin protection gels based on polyacrylates.

Science.gov (United States)

Kulawik-Pióro, Agnieszka; Kurpiewska, Joanna; Kułaszka, Agnieszka

2018-03-01

With the current increases in occupational skin diseases, literature data attesting the decreasing efficiency of barrier creams with respect to the manufacturer's declarations and legal regulations granting skin protection gels for employees, research is required to analyse and evaluate the recipes used for hydrophilic skin protection gels based on polyacrylates. This study investigated the rheological properties, pH and sensory perception of hydrophilic barrier gels based on polyacrylates. The acrylic acid derivatives used were good thickeners, and helped to form transparent gels of adequate durability. They could be used to create hydrophilic films on the surface of the skin to protect it against hydrophobic substances. A correlation was shown between the results of the rheological properties and the barrier properties of the gels. This confirms the possibility of monitoring the quality of the gels at the stage of recipe development. Polyacrylates are viable for use in industry to produce hydrophilic barrier creams suitable for skin protection.

Cost and effectiveness of radon barrier systems

International Nuclear Information System (INIS)

Baker, E.G.; Freeman, H.D.; Hartley, J.N.; Gee, G.W.

1982-12-01

Earthen, asphalt, and multilayer radon barrier systems can all provide reduction in the amount of radon gas released from uranium mill tailings. Pacific Northwest Laboratory field tested all three types of covers at Grand Junction, Colorado during the summer of 1981. All nine individual radon barrier systems tested currently meet the EPA standard for radon flux of 20 pCi m - 2 s - 1 . The cost of the asphalt and 3m earthen covers were about the same at the field test. Multilayer covers were significantly more costly. Cost estimates for three high priority western sites indicate 3m of earthen cover is the least costly radon barrier when earthen material is available at or near the disposal site. If earthen material must be imported more than 8 to 10 km asphalt and possibly multilayer radon barriers can be cost effective

Lightning protection design and testing of an all composite wet wing for the Egrett

Science.gov (United States)

Burrows, B. J. C.; Haigh, S. J.; Chessum, C.; Dunkley, V. P.

1991-01-01

The Egrett aircraft has an all composite wing comprising CFC(carbon fiber composite)/Nomex sandwich skins, full length CFC main spar caps, and GFRP (glass fiber reinforced plastics) main and auxiliary spar webs. It also has short inboard CFC auxiliary spar caps. It has fine aluminum wires woven into the surface for protection. It has an integral fuel tank using the CFC/Nomex skins as the upper and lower tank walls, and lies between the forward auxiliary spar and the forward of the two main spar webs. The fuel tank is not bagged, i.e., it is in effect a wet wing tank. It has conventional capacitive type fuel gauging. The aircraft was cleared to IFR standards and so required full lightning protection and demonstration that it would survive the lightning environment. The lightning protection was designed for the wing (and also for the remainder of the aircraft). An inner wing test samples (which included a part of the fuel tank) were tested as part of the proving program. The protection design and the testing process are described. The intrinsic structural features are indicated that improve lightning protection design and which therefore minimize the weight and cost of any added lightning protection components.

Long-Term Climate Change Assessment Task for the Hanford Site Permanent Isolation Barrier Development Program: Status through FY 1992

International Nuclear Information System (INIS)

Petersen, K.L.; Chatters, J.C.

1993-07-01

The Hanford Site Permanent Isolation Barrier Development Program (Barrier Development Program) was organized (Adams and Wing 1986) to develop the technology needed to provide an in-place disposal capability for the US Department of Energy at the Hanford Site in southeastern Washington. The goals of the Barrier Development Program are to provide defensible evidence that final barrier design(s) will adequately control water infiltration, plant and animal intrusion, and wind and water erosion for a minimum of 1,000 years; to isolate wastes from the accessible environment; and to use markers to warn inadvertent human intruders. Evidence for barrier performance will be obtained by conducting laboratory experiments, field tests, computer modeling, and other studies that establish confidence in the barrier's ability to meet its 1,000-year design life. The performance and stability of natural barrier analogs that have existed for several millennia and the reconstruction of climate changes during the past 10,000 to 125,000 years also will provide insight into bounding conditions of possible future changes and increase confidence in the barriers design. In the following discussion the term open-quotes long-termclose quotes references periods of time up to 1000's of years, distinguishing it from open-quotes short-termclose quotes weather patterns covering a decade or less. Specific activities focus on planning and conducting a series of studies and tests required to confirm key aspects of the barrier design. The effort is a collaborative one between scientists and engineers from Westinghouse Hanford Company (Westinghouse Hanford) and Pacific Northwest Laboratory (PNL) to design barriers to limit movement of radionuclides and other contaminants to the accessible environment for at least 1,000 years. These activities have been divided into 14 groups of tasks that aid in the complete development of protective barrier and warning marker system

Epidermal Growth Factor and Intestinal Barrier Function

Directory of Open Access Journals (Sweden)

Xiaopeng Tang

2016-01-01

Full Text Available Epidermal growth factor (EGF is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health.

Turbine-missile casing exit tests

International Nuclear Information System (INIS)

Yoshimura, H.R.; Sliter, G.E.

1978-01-01

Nuclear power plant designers are required to provide safety-related components with adequate protection against hypothetical turbine-missile impacts. In plants with a ''peninsula'' arrangement, protection is provided by installing the turbine axis radially from the reactor building, so that potential missile trajectories are not in line with the plant. In plants with a ''non-peninsula'' arrangement (turbine axis perpendicular to a radius), designers rely on the low probability of a missile strike and on the protection provided by reinforced concrete walls in order to demonstrate an adequate level of protection USNRC Regulatory Guide 1.115). One of the critical first steps in demonstrating adequacy is the determination of the energy and spin of the turbine segments as they exit the turbine casing. The spin increases the probability that a subsequent impact with a protective barrier will be off-normal and therefore less severe than the normal impact assumed in plant designs. Two full-scale turbine-missile casing exit tests which were conducted by Sandia Laboratories at their rocket-sled facility in Albuquerque, New Mexico, are described. Because of wide variations in turbine design details, postulated failure conditions, and missile exit scenarios, the conditions for the two tests were carefully selected to be as prototypical as possible, while still maintaining the well-controlled and well-characterized test conditions needed for generating benchmark data

The field migration tests of 237Np, 238Pu, 241Am and 90Sr in aerated loess, aquifer and engineering barrier materials

International Nuclear Information System (INIS)

Li Shushen; Wang Zhiming; Zhao Yingjie; Fan Zhiwen; Liu Chunli; An Yongfeng; Yang Yue'e; Wu Qinghua

2003-01-01

This paper introduces the field migration tests of 237 Np, 238 Pu, 241 Am and 90 Sr in aerated loess, aquifer and engineering barrier materials. The tests in the aerated loess and engineering barrier materials were carried out under both natural and artificial sprinkling (15 mm/d) conditions. The tests in aquifer were carried out in both assemblies packed with undisturbed aquifer media and a definite undisturbed area. The results indicate that after 3 years tests no significant migrations were seen for all nuclides in engineering barrier materials under two kinds of conditions and in aerated loess under natural conditions. For the aerated loess under artificial sprinkling conditions, 2.7 cm (center of mass) migration in the area directly below the sand tracer layer (named as area 1) and 13 cm (peak) migration in the area outside the area 1 for 90 Sr were observed; There was no migration for 237 Np, 238 Pu and 241 Am. It was discovered that the sand layer used as carrier of nuclide tracer has barrier effect on unsaturated water and an influence on nuclide migration. This has been demonstrated by the inter comparison experiment with both sand and loess as tracer carrier. In the tracer tests of undisturbed aquifer area there was no significant migration of 237 Np, 238 Pu, 241 Am and 90 Sr after 1023 days. In the assembly 8 there was no significant migration for 238 Pu and 241 Am and a small backward migration 0.95 cm for 237 Np and 4.7 cm migration (center of mass) for 90 Sr were observed. The tests also indicate that there is no significant difference of nuclide migration in ordinary and degraded cement

Simulating complex noise barrier reflections

NARCIS (Netherlands)

Eerden, F.J.M. van der; Lutgendorf, D.; Roo, F. de

2011-01-01

Within the EU FP7 QUIESST project, QUIeting the Environment for a Sustainable Surface Transport, a test method is being developed for the reflectivity of noise barriers. The method needs to account for a complex shape of barriers and the use of various types of absorbing materials. The performance

Radiation protection training award - an innovative approach of testing radiation protection skills in catastrophe management

International Nuclear Information System (INIS)

Geringer, T.

2003-01-01

Full text: ARC Seibersdorf research is Austria's largest independent research institution. Apart from research and technical development, ARCS also offers special training an radiation protection. Having undergone intensive radiation protection training, security forces are also entitled to test their knowledge in a special 'radiation protection training award'. The prize is awarded in three different grades. ARCS Bronze award guarantees that the holder is competent in, both theoretical and practical aspects of a radiological accident. The follow-up Silver award requires additional competence in emergency management. Candidates having at least five years of professional experience and presenting a written thesis are considered for the Golden award. The holder is not only experienced in radiological catastrophe management including a competent theoretical background, but is also experienced enough to work out and improve his own emergency planning. ARC Seibersdorf research started with their radiation protection award as early as 1968. More then 10 000 candidates have been awarded since then. Most candidates are members of the Austrian Army or other security forces, although everyone above the age of 18 and undergone a basic course in radiation protection is entitled to participate. Even company internal awards have been given to ensure the quality of training applies to ARC Seibersdorf members as well. The prize is awarded in three different grades. ARCS Bronze award guarantees that the holder is competent in both theoretical and practical aspects of a radiological accident. The followup Silver award requires additional competence in emergency management. Candidates having at least five years of professional experience and presenting a written thesis, are considered for the Golden award. The holder is not only experienced in radiological catastrophe management including a competent theoretical background, but is also experienced enough to work out and improve his

Reviews of the In-situ Demonstration Test of the Engineered Barrier System in Many Countries

Energy Technology Data Exchange (ETDEWEB)

Lee, Minsoo; Choi, Heui Joo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-10-15

Many nations considering the deep geologic disposal of HLW are now planning or executing in-situ demonstration experiments on their regional EBS (Engineering barrier system) at their deep underground research facilities. The main purpose of the in-situ EBS test is the experimental confirmation of its performance, and the prediction of its long-term evolution through the modeling of EBS based on the experimental data. Additionally, the engineering feasibility for the construction of an engineering barrier system can also be checked through full scale construction of an in-situ test. KAERI is currently preparing an in-situ test at a large 1/3 scale, called IN-DEBS (In-situ Demonstration of EBS) at KURT (KAERI Underground Research Tunnel) for the generic EBS suggested in A-KRS (Advanced KAERI Reference System), which was developed to treat the HLW from pyroprocessing. As the first step for the design of IN-DEBS, the foreign in-situ demonstrations of EBS were reviewed in this paper. The demonstration projects, which were completed or are still being executed in some countries such as Sweden, France, Finland, Canada, Belgium, Switzerland, Spain, and Japan, were surveyed and summarized. In particular, hardware constitutions such as the heating element or compact bentonite, and the experimental procedures, have focused more on reviews than on experimental results in this survey, since their hardware information is very important for the design of the IN-DEBS.

Reviews of the In-situ Demonstration Test of the Engineered Barrier System in Many Countries

International Nuclear Information System (INIS)

Lee, Minsoo; Choi, Heui Joo

2013-01-01

Many nations considering the deep geologic disposal of HLW are now planning or executing in-situ demonstration experiments on their regional EBS (Engineering barrier system) at their deep underground research facilities. The main purpose of the in-situ EBS test is the experimental confirmation of its performance, and the prediction of its long-term evolution through the modeling of EBS based on the experimental data. Additionally, the engineering feasibility for the construction of an engineering barrier system can also be checked through full scale construction of an in-situ test. KAERI is currently preparing an in-situ test at a large 1/3 scale, called IN-DEBS (In-situ Demonstration of EBS) at KURT (KAERI Underground Research Tunnel) for the generic EBS suggested in A-KRS (Advanced KAERI Reference System), which was developed to treat the HLW from pyroprocessing. As the first step for the design of IN-DEBS, the foreign in-situ demonstrations of EBS were reviewed in this paper. The demonstration projects, which were completed or are still being executed in some countries such as Sweden, France, Finland, Canada, Belgium, Switzerland, Spain, and Japan, were surveyed and summarized. In particular, hardware constitutions such as the heating element or compact bentonite, and the experimental procedures, have focused more on reviews than on experimental results in this survey, since their hardware information is very important for the design of the IN-DEBS

Nurse-patient communication barriers in Iranian nursing.