Demonstration and Validation of a Regenerated Cellulose Dialysis Membrane Diffusion Sampler for Monitoring Ground-Water Quality and Remediation Progress at DoD Site: Perchlorate and Ordnance Compounds

DTIC Science & Technology

2011-10-01

Regulatory Council LDPE low-density polyethylene MDL minimum detection limit NAVFAC ESC Naval Facilities Engineering Command Engineering Service...membrane sampler design consists of a tubular-shaped bag made of flexible low-density polyethylene ( LDPE ) (Vroblesky, 2001a, 2001b). The LDPE tube is...requirements, and can be constructed from small-diameter LDPE tubing that fits into small- 4 diameter wells. These polyethylene diffusion bag

Expression of Anti-apoptotic Protein BAG3 in Human Sebaceous Gland Carcinoma of the Eyelid.

PubMed

Yunoki, Tatsuya; Tabuchi, Yoshiaki; Hayashi, Atsushi

2017-04-01

Bcl-2-associated athanogene 3 (BAG3), a co-chaperone of heat shock protein 70 (HSP70), has been shown to play a role in anti-apoptosis of various malignant tumors. In this study, the expression of BAG3 was examined in human sebaceous gland carcinoma of the eyelid. The expression of BAG3 was evaluated by immunohistochemistry of surgical samples from 5 patients with sebaceous gland carcinoma in the eyelid. BAG3 was positive diffusely in the cytoplasm in all patients. The average positive rate of BAG3 was 73.0±26.0% in tumor cells of all patients. BAG3 was highly expressed in sebaceous gland carcinoma of the eyelid. BAG3 may play an important role in the pathogenesis and progression of sebaceous gland carcinoma of the eyelid. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Vertical Diffusivities of Active and Passive Tracers

NASA Technical Reports Server (NTRS)

Canuto, V. M.; Cheng, Y.; Howard, A. M.

2010-01-01

The climate models that include a carbon-cycle need the vertical diffusivity of a passive tracer. Since an expression for the latter is not available, it has been common practice to identify it with that of salt. The identification is questionable since T, S are active, not passive tracers. We present the first derivation of the diffusivity of a passive tracer in terms of Ri (Richardson number) and Rq (density ratio, ratio of salinity over temperature z-gradients). The following results have emerged: (a) The passive tracer diffusivity is an algebraic function of Ri, Rq. (b) In doubly stable regimes (DS, partial derivative of T with respect to z > 0, partial derivative of S with respect to z < 0), the passive scalar diffusivity is nearly the same as that of salt/heat for any values of Rq < 0 and Ri > 0. (c) In DC regimes (diffusive convection, partial derivative of T with respect to z < 0, partial derivative of S with respect to z < 0, Rq > 1), the passive scalar diffusivity is larger than that of salt. At Ri = O(1), it can be more than twice as large. (d) In SF regimes (salt fingers, partial derivative of T with respect to z > 0, partial derivative of S with respect to z > 0, Rq < 1), the passive scalar diffusivity is smaller than that of salt. At Ri = O(1), it can be less than half of it. (e) The passive tracer diffusivity predicted at the location of NATRE (North Atlantic Tracer Release Experiment) is discussed. (f) Perhaps the most relevant conclusion is that the common identification of the tracer diffusivity with that of salt is valid only in DS regimes. In the Southern Ocean, where there is the largest CO2 absorption, the dominant regime is diffusive convection discussed in (c) above.

Continued geophysical logging near the GMH Electronics National Priorities List Superfund site near Roxboro, North Carolina

USGS Publications Warehouse

Antolino, Dominick J.; Chapman, Melinda J.

2017-01-06

The U.S. Geological Survey South Atlantic Water Science Center collected borehole geophysical logs and images and continuous water-level data near the GMH Electronics National Priorities List Superfund site near Roxboro, North Carolina, during December 2012 through July 2015. Previous work by the U.S. Geological Survey South Atlantic Water Science Center at the site involved the collection of borehole geophysical log data in 15 wells, in addition to surface geologic mapping and passive diffusion bag sampling. In a continued effort to assist the U.S. Environmental Protection Agency in developing a conceptual groundwater model to assess current contaminant distribution and future migration of contaminants, more than 900 subsurface features (primarily fracture orientations) in 10 open borehole wells were delineated and continuous water-level data information from 14 monitoring wells within close proximity of the initially drilled boreholes was collected to observe any induced water-level fluctuations during drilling operations

Method for vacuum pressing electrochemical cell components

NASA Technical Reports Server (NTRS)

Andrews, Craig C. (Inventor); Murphy, Oliver J. (Inventor)

2004-01-01

Assembling electrochemical cell components using a bonding agent comprising aligning components of the electrochemical cell, applying a bonding agent between the components to bond the components together, placing the components within a container that is essentially a pliable bag, and drawing a vacuum within the bag, wherein the bag conforms to the shape of the components from the pressure outside the bag, thereby holding the components securely in place. The vacuum is passively maintained until the adhesive has cured and the components are securely bonded. The bonding agent used to bond the components of the electrochemical cell may be distributed to the bonding surface from distribution channels in the components. To prevent contamination with bonding agent, some areas may be treated to produce regions of preferred adhesive distribution and protected regions. Treatments may include polishing, etching, coating and providing protective grooves between the bonding surfaces and the protected regions.

Bagging system, soil stabilization mat, and tent frame for a lunar base

NASA Technical Reports Server (NTRS)

1990-01-01

Georgia Tech's School of Textile and Fiber Engineering and School of Mechanical Engineering participated in four cooperative design efforts this year. Each of two interdisciplinary teams designed a system consisting of a lunar regolith bag and an apparatus for filling this bag. The third group designed a mat for stabilization of lunar soil during takeoff and landing, and a method for packaging and deploying this mat. Finally, the fourth group designed a sunlight diffusing tent to be used as a lunar worksite. Summaries of these projects are given.

Bagging system, soil stabilization mat, and tent frame for a lunar base

NASA Astrophysics Data System (ADS)

1990-11-01

Georgia Tech's School of Textile and Fiber Engineering and School of Mechanical Engineering participated in four cooperative design efforts this year. Each of two interdisciplinary teams designed a system consisting of a lunar regolith bag and an apparatus for filling this bag. The third group designed a mat for stabilization of lunar soil during takeoff and landing, and a method for packaging and deploying this mat. Finally, the fourth group designed a sunlight diffusing tent to be used as a lunar worksite. Summaries of these projects are given.

Equivalent Air Spring Suspension Model for Quarter-Passive Model of Passenger Vehicles.

PubMed

Abid, Haider J; Chen, Jie; Nassar, Ameen A

2015-01-01

This paper investigates the GENSIS air spring suspension system equivalence to a passive suspension system. The SIMULINK simulation together with the OptiY optimization is used to obtain the air spring suspension model equivalent to passive suspension system, where the car body response difference from both systems with the same road profile inputs is used as the objective function for optimization (OptiY program). The parameters of air spring system such as initial pressure, volume of bag, length of surge pipe, diameter of surge pipe, and volume of reservoir are obtained from optimization. The simulation results show that the air spring suspension equivalent system can produce responses very close to the passive suspension system.

Equivalent Air Spring Suspension Model for Quarter-Passive Model of Passenger Vehicles

PubMed Central

Abid, Haider J.; Chen, Jie; Nassar, Ameen A.

2015-01-01

This paper investigates the GENSIS air spring suspension system equivalence to a passive suspension system. The SIMULINK simulation together with the OptiY optimization is used to obtain the air spring suspension model equivalent to passive suspension system, where the car body response difference from both systems with the same road profile inputs is used as the objective function for optimization (OptiY program). The parameters of air spring system such as initial pressure, volume of bag, length of surge pipe, diameter of surge pipe, and volume of reservoir are obtained from optimization. The simulation results show that the air spring suspension equivalent system can produce responses very close to the passive suspension system. PMID:27351020

Development of Spray on Bag for manufacturing of large composites parts: Diffusivity analysis

NASA Astrophysics Data System (ADS)

Dempah, Maxime Joseph

Bagging materials are utilized in many composites manufacturing processes. The selection is mainly driven by cost, temperature requirements, chemical compatibility and tear properties of the bag. The air barrier properties of the bag are assumed to be adequate or in many cases are not considered at all. However, the gas barrier property of a bag is the most critical parameter, as it can negatively affect the quality of the final laminate. The barrier property is a function of the bag material, uniformity, thickness and temperature. Improved barrier properties are needed for large parts, high pressure consolidated components and structures where air stays entrapped on the part surface. The air resistance property of the film is defined as permeability and is investigated in this thesis. A model was developed to evaluate the gas transport through the film and an experimental cell was implemented to characterize various commercial films. Understanding and characterizing the transport phenomena through the film allows optimization of the bagging material for various manufacturing processes. Spray-on-Bag is a scalable alternative bagging method compared to standard films. The approach allows in-situ fabrication of the bag on large and complex geometry structures where optimization of the bag properties can be varied on a local level. An experimental setup was developed and implemented using a six axis robot and an automated spraying system. Experiments were performed on a flat surface and specimens were characterized and compared to conventional films. Air barrier properties were within range of standard film approaches showing the potential to fabricate net shape bagging structures in an automated process.

Simple rules for passive diffusion through the nuclear pore complex

PubMed Central

Mironska, Roxana; Kim, Seung Joong

2016-01-01

Passive macromolecular diffusion through nuclear pore complexes (NPCs) is thought to decrease dramatically beyond a 30–60-kD size threshold. Using thousands of independent time-resolved fluorescence microscopy measurements in vivo, we show that the NPC lacks such a firm size threshold; instead, it forms a soft barrier to passive diffusion that intensifies gradually with increasing molecular mass in both the wild-type and mutant strains with various subsets of phenylalanine-glycine (FG) domains and different levels of baseline passive permeability. Brownian dynamics simulations replicate these findings and indicate that the soft barrier results from the highly dynamic FG repeat domains and the diffusing macromolecules mutually constraining and competing for available volume in the interior of the NPC, setting up entropic repulsion forces. We found that FG domains with exceptionally high net charge and low hydropathy near the cytoplasmic end of the central channel contribute more strongly to obstruction of passive diffusion than to facilitated transport, revealing a compartmentalized functional arrangement within the NPC. PMID:27697925

BAG3 Is a Modular, Scaffolding Protein that physically Links Heat Shock Protein 70 (Hsp70) to the Small Heat Shock Proteins.

PubMed

Rauch, Jennifer N; Tse, Eric; Freilich, Rebecca; Mok, Sue-Ann; Makley, Leah N; Southworth, Daniel R; Gestwicki, Jason E

2017-01-06

Small heat shock proteins (sHsps) are a family of ATP-independent molecular chaperones that are important for binding and stabilizing unfolded proteins. In this task, the sHsps have been proposed to coordinate with ATP-dependent chaperones, including heat shock protein 70 (Hsp70). However, it is not yet clear how these two important components of the chaperone network are linked. We report that the Hsp70 co-chaperone, BAG3, is a modular, scaffolding factor to bring together sHsps and Hsp70s. Using domain deletions and point mutations, we found that BAG3 uses both of its IPV motifs to interact with sHsps, including Hsp27 (HspB1), αB-crystallin (HspB5), Hsp22 (HspB8), and Hsp20 (HspB6). BAG3 does not appear to be a passive scaffolding factor; rather, its binding promoted de-oligomerization of Hsp27, likely by competing for the self-interactions that normally stabilize large oligomers. BAG3 bound to Hsp70 at the same time as Hsp22, Hsp27, or αB-crystallin, suggesting that it might physically bring the chaperone families together into a complex. Indeed, addition of BAG3 coordinated the ability of Hsp22 and Hsp70 to refold denatured luciferase in vitro. Together, these results suggest that BAG3 physically and functionally links Hsp70 and sHsps. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preventing hypothermia: comparison of current devices used by the US Army in an in vitro warmed fluid model.

PubMed

Allen, Paul B; Salyer, Steven W; Dubick, Michael A; Holcomb, John B; Blackbourne, Lorne H

2010-07-01

The purpose of this study was to develop an in vitro torso model constructed with fluid bags and to determine whether this model could be used to differentiate between the heat prevention performance of devices with active chemical or radiant forced-air heating systems compared with passive heat loss prevention devices. We tested three active (Hypothermia Prevention Management Kit [HPMK], Ready-Heat, and Bair Hugger) and five passive (wool, space blankets, Blizzard blankets, human remains pouch, and Hot Pocket) hypothermia prevention products. Active warming devices included products with chemically or electrically heated systems. Both groups were tested on a fluid model warmed to 37 degrees C versus a control with no warming device. Core temperatures were recorded every 5 minutes for 120 minutes in total. Products that prevent heat loss with an actively heated element performed better than most passive prevention methods. The original HPMK achieved and maintained significantly higher temperatures than all other methods and the controls at 120 minutes (p < 0.05). None of the devices with an actively heated element achieved the sustained 44 degrees C that could damage human tissue if left in place for 6 hours. The best passive methods of heat loss prevention were the Hot Pocket and Blizzard blanket, which performed the same as two of the three active heating methods tested at 120 minutes. Our in vitro fluid bag "torso" model seemed sensitive to detect heat loss in the evaluation of several active or passive warming devices. All active and most passive devices were better than wool blankets. Under conditions near room temperature, passive warming methods (Blizzard blanket or the Hot Pocket) were as effective as active warming devices other than the original HPMK. Further studies are necessary to determine how these data can translate to field conditions in preventing heat loss in combat casualties.

BAG3 is involved in neuronal differentiation and migration.

PubMed

Santoro, Antonietta; Nicolin, Vanessa; Florenzano, Fulvio; Rosati, Alessandra; Capunzo, Mario; Nori, Stefania L

2017-05-01

Bcl2-associated athanogene 3 (BAG3) protein belongs to the family of co-chaperones interacting with several heat shock proteins. It plays a key role in protein quality control and mediates the clearance of misfolded proteins. Little is known about the expression and cellular localization of BAG3 during nervous system development and differentiation. Therefore, we analyze the subcellular distribution and expression of BAG3 in nerve-growth-factor-induced neurite outgrowth in PC12 cells and in developing and adult cortex of mouse brain. In differentiated PC12 cells, BAG3 was localized mainly in the neuritic domain rather than the cell body, whereas in control cells, it appeared to be confined to the cytoplasm near the nuclear membrane. Interestingly, the change of BAG3 localization during neuronal differentiation was associated only with a slight increase in total BAG3 expression. These data were coroborated by transmission electron microscopy showing that BAG3 was confined mainly within large dense-core vesicles of the axon in differentiated PC12 cells. In mouse developing cortex, BAG3 appeared to be intensely expressed in cellular processes of migrating cells, whereas in adult brain, a diffuse expression of low to medium intensity was detected in neuronal cell bodies. These findings suggest that BAG3 expression is required for neuronal differentiation and migration and that its role is linked to a change in its distribution pattern rather than to an increase in its protein expression levels.

Passive lipoidal diffusion and carrier-mediated cell uptake are both important mechanisms of membrane permeation in drug disposition.

PubMed

Smith, Dennis; Artursson, Per; Avdeef, Alex; Di, Li; Ecker, Gerhard F; Faller, Bernard; Houston, J Brian; Kansy, Manfred; Kerns, Edward H; Krämer, Stefanie D; Lennernäs, Hans; van de Waterbeemd, Han; Sugano, Kiyohiko; Testa, Bernard

2014-06-02

Recently, it has been proposed that drug permeation is essentially carrier-mediated only and that passive lipoidal diffusion is negligible. This opposes the prevailing hypothesis of drug permeation through biological membranes, which integrates the contribution of multiple permeation mechanisms, including both carrier-mediated and passive lipoidal diffusion, depending on the compound's properties, membrane properties, and solution properties. The prevailing hypothesis of drug permeation continues to be successful for application and prediction in drug development. Proponents of the carrier-mediated only concept argue against passive lipoidal diffusion. However, the arguments are not supported by broad pharmaceutics literature. The carrier-mediated only concept lacks substantial supporting evidence and successful applications in drug development.

Performance of distributed bagged stone dust barrier in combating coal-dust explosions

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

Plessis, J.J.L. du; Vassard, P.S.

1999-07-01

The Kloppersbos Research Facility of the CSIR's Division of Mining Technology has developed a new method of building stone dust barriers. The new barrier makes use of a previous concept of containing stone dust in a bag, but incorporates a new method of rupturing the bag. This was achieved by adapting the closing mechanism and by balancing the stone dust content with the void in the bag. The bagged barrier was extensively tested in the 200-m test gallery. During these tests, it became evident that these bags could be made to rupture and spread stone dust when subjected to smallermore » forces than those required for the most commonly used passive barrier, the Polish light barrier. To validate this, as well as to gain international acceptance of this new barrier, tests were conducted in the German experimental mine, DMT Tremonia, Dortmund. The barrier was evaluated against numerous methane-initiated coal-dust explosions. The paper describes the successful inhibition of coal-dust explosions at Kloppersbos and DMT tremonia. The barrier has been proven successfully for static pressures of 44 to 82 kpa, dynamic pressures of 12 to 36 kpa and for flame speeds as low as 23 m/s. This barrier is now accepted by the South African government and has been implemented in numerous South African collieries.« less

Double-layer Tedlar bags: a means to limit humidity evolution of air samples and to dry humid air samples.

PubMed

Cariou, Stephane; Guillot, Jean-Michel

2006-01-01

Tedlar bags, which are widely used to collect air samples, especially VOCs and odorous atmospheres, can allow humidity to diffuse when relative humidity levels differ between the inside and outside. Starting with dry air inside the bag and humid air outside, we monitored equilibrium times under several conditions showing the evolution and influence of collected volumes and exposed surfaces. A double-film Tedlar bag was made, to limit the impact of external humidity on a sample at low humidity level. With the addition of a drying agent between both films, the evolution of humidity of a sample can be stopped for several hours. When a VOC mixture was monitored in a humid atmosphere, humidity was decreased but no significant evolution of VOC concentrations was observed.

Evidence-based approach to assess passive diffusion and carrier-mediated drug transport.

PubMed

Di, Li; Artursson, Per; Avdeef, Alex; Ecker, Gerhard F; Faller, Bernard; Fischer, Holger; Houston, J Brian; Kansy, Manfred; Kerns, Edward H; Krämer, Stefanie D; Lennernäs, Hans; Sugano, Kiyohiko

2012-08-01

Evidence supporting the action of passive diffusion and carrier-mediated (CM) transport in drug bioavailability and disposition is discussed to refute the recently proposed theory that drug transport is CM-only and that new transporters will be discovered that possess transport characteristics ascribed to passive diffusion. Misconceptions and faulty speculations are addressed to provide reliable guidance on choosing appropriate tools for drug design and optimization. Copyright © 2012 Elsevier Ltd. All rights reserved.

Demonstration and Validation of a Regenerated Cellulose Dialysis Membrane Diffusion Sampler for Monitoring Ground Water Quality and Remediation Progress at DoD Sites

DTIC Science & Technology

2007-08-30

ITRC Interstate Technology Regulatory Council LRL Laboratory reporting level LDPE Low-density polyethylene MDL Minimum detection limit MNA...diameter of the well. Another diffusion membrane sampler design consists of a tubular-shaped bag made of flexible low-density polyethylene ( LDPE ...

Finite-time robust passive control for a class of switched reaction-diffusion stochastic complex dynamical networks with coupling delays and impulsive control

NASA Astrophysics Data System (ADS)

Syed Ali, M.; Yogambigai, J.; Kwon, O. M.

2018-03-01

Finite-time boundedness and finite-time passivity for a class of switched stochastic complex dynamical networks (CDNs) with coupling delays, parameter uncertainties, reaction-diffusion term and impulsive control are studied. Novel finite-time synchronisation criteria are derived based on passivity theory. This paper proposes a CDN consisting of N linearly and diffusively coupled identical reaction- diffusion neural networks. By constructing of a suitable Lyapunov-Krasovskii's functional and utilisation of Jensen's inequality and Wirtinger's inequality, new finite-time passivity criteria for the networks are established in terms of linear matrix inequalities (LMIs), which can be checked numerically using the effective LMI toolbox in MATLAB. Finally, two interesting numerical examples are given to show the effectiveness of the theoretical results.

Open-circuit respirometry: a brief historical review of the use of Douglas bags and chemical analyzers.

PubMed

Shephard, Roy J

2017-03-01

The Douglas bag technique is reviewed as one in a series of articles looking at historical insights into measurement of whole body metabolic rate. Consideration of all articles looking at Douglas bag technique and chemical gas analysis has here focused on the growing appreciation of errors in measuring expired volumes and gas composition, and subjective reactions to airflow resistance and dead space. Multiple small sources of error have been identified and appropriate remedies proposed over a century of use of the methodology. Changes in the bag lining have limited gas diffusion, laboratories conducting gas analyses have undergone validation, and WHO guidelines on airflow resistance have minimized reactive effects. One remaining difficulty is a contamination of expirate by dead space air, minimized by keeping the dead space <70 mL. Care must also be taken to ensure a steady state, and formal validation of the Douglas bag method still needs to be carried out. We may conclude that the Douglas bag method has helped to define key concepts in exercise physiology. Although now superceded in many applications, the errors in a meticulously completed measurement are sufficiently low to warrant retention of the Douglas bag as the gold standard when evaluating newer open-circuit methodology.

Cellular automaton formulation of passive scalar dynamics

NASA Technical Reports Server (NTRS)

Chen, Hudong; Matthaeus, William H.

1987-01-01

Cellular automata modeling of the advection of a passive scalar in a two-dimensional flow is examined in the context of discrete lattice kinetic theory. It is shown that if the passive scalar is represented by tagging or 'coloring' automation particles a passive advection-diffusion equation emerges without use of perturbation expansions. For the specific case of the hydrodynamic lattice gas model of Frisch et al. (1986), the diffusion coefficient is calculated by perturbation.

Visualizing Molecular Diffusion through Passive Permeability Barriers in Cells: Conventional and Novel Approaches

PubMed Central

Lin, Yu-Chun; Phua, Siew Cheng; Lin, Benjamin; Inoue, Takanari

2013-01-01

Diffusion barriers are universal solutions for cells to achieve distinct organizations, compositions, and activities within a limited space. The influence of diffusion barriers on the spatiotemporal dynamics of signaling molecules often determines cellular physiology and functions. Over the years, the passive permeability barriers in various subcellular locales have been characterized using elaborate analytical techniques. In this review, we will summarize the current state of knowledge on the various passive permeability barriers present in mammalian cells. We will conclude with a description of several conventional techniques and one new approach based on chemically-inducible diffusion trap (C-IDT) for probing permeable barriers. PMID:23731778

Passive absolute age and temperature history sensor

DOEpatents

Robinson, Alex; Vianco, Paul T.

2015-11-10

A passive sensor for historic age and temperature sensing, including a first member formed of a first material, the first material being either a metal or a semiconductor material and a second member formed of a second material, the second material being either a metal or a semiconductor material. A surface of the second member is in contact with a surface of the first member such that, over time, the second material of the second member diffuses into the first material of the first member. The rate of diffusion for the second material to diffuse into the first material depends on a temperature of the passive sensor. One of the electrical conductance, the electrical capacitance, the electrical inductance, the optical transmission, the optical reflectance, or the crystalline structure of the passive sensor depends on the amount of the second material that has diffused into the first member.

Visualizing molecular diffusion through passive permeability barriers in cells: conventional and novel approaches.

PubMed

Lin, Yu-Chun; Phua, Siew Cheng; Lin, Benjamin; Inoue, Takanari

2013-08-01

Diffusion barriers are universal solutions for cells to achieve distinct organizations, compositions, and activities within a limited space. The influence of diffusion barriers on the spatiotemporal dynamics of signaling molecules often determines cellular physiology and functions. Over the years, the passive permeability barriers in various subcellular locales have been characterized using elaborate analytical techniques. In this review, we will summarize the current state of knowledge on the various passive permeability barriers present in mammalian cells. We will conclude with a description of several conventional techniques and one new approach based on chemically inducible diffusion trap (CIDT) for probing permeable barriers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Geophysical Logs, Specific Capacity, and Water Quality of Four Wells at Rogers Mechanical (former Tate Andale) Property, North Penn Area 6 Superfund Site, Lansdale, Pennsylvania, 2006-07

USGS Publications Warehouse

Senior, Lisa A.; Bird, Philip H.

2010-01-01

As part of technical assistance to the U.S. Environmental Protection Agency (USEPA) in the remediation of properties on the North Penn Area 6 Superfund Site in Lansdale, Pa., the U.S. Geological Survey (USGS) in 2006-07 collected data in four monitor wells at the Rogers Mechanical (former Tate Andale) property. During this period, USGS collected and analyzed borehole geophysical and video logs of three new monitor wells (Rogers 4, Rogers 5, and Rogers 6) ranging in depth from 80 to 180 feet, a borehole video log and additional heatpulse-flowmeter measurements (to quantify vertical borehole flow) in one existing 100-foot deep well (Rogers 3S), and water-level data during development of two wells (Rogers 5 and Rogers 6) to determine specific capacity. USGS also summarized results of passive-diffusion bag sampling for volatile organic compounds (VOCs) in the four wells. These data were intended to help understand the groundwater system and the distribution of VOC contaminants in groundwater at the property.

A study of X100 pipeline steel passivation in mildly alkaline bicarbonate solutions using electrochemical impedance spectroscopy under potentiodynamic conditions and Mott-Schottky

NASA Astrophysics Data System (ADS)

Gadala, Ibrahim M.; Alfantazi, Akram

2015-12-01

The key steps involved in X100 pipeline steel passivation in bicarbonate-based simulated soil solutions from the pre-passive to transpassive potential regions have been analyzed here using a step-wise anodizing-electrochemical impedance spectroscopy (EIS) routine. Pre-passive steps involve parallel dissolution-adsorption in early stages followed by clear diffusion-adsorption control shortly before iron hydroxide formation. Aggressive NS4 chlorides/sulfate promote steel dissolution whilst inhibiting diffusion in pre-passive steps. Diffusive and adsorptive effects remain during iron hydroxide formation, but withdraw shortly thereafter during its removal and the development of the stable iron carbonate passive layer. Passive layer protectiveness is evaluated using EIS fitting, current density analysis, and correlations with semiconductive parameters, consistently revealing improved robustness in colder, bicarbonate-rich, chloride/sulfate-free conditions. Ferrous oxide formation at higher potentials results in markedly lower impedances with disordered behavior, and the involvement of the iron(III) valence state is observed in Mott-Schottky tests exclusively for 75 °C conditions.

A Single Chip Automotive Control LSI Using SOI Bipolar Complimentary MOS Double-Diffused MOS

NASA Astrophysics Data System (ADS)

Kawamoto, Kazunori; Mizuno, Shoji; Abe, Hirofumi; Higuchi, Yasushi; Ishihara, Hideaki; Fukumoto, Harutsugu; Watanabe, Takamoto; Fujino, Seiji; Shirakawa, Isao

2001-04-01

Using the example of an air bag controller, a single chip solution for automotive sub-control systems is investigated, by using a technological combination of improved circuits, bipolar complimentary metal oxide silicon double-diffused metal oxide silicon (BiCDMOS) and thick silicon on insulator (SOI). For circuits, an automotive specific reduced instruction set computer (RISC) center processing unit (CPU), and a novel, all integrated system clock generator, dividing digital phase-locked loop (DDPLL) are proposed. For the device technologies, the authors use SOI-BiCDMOS with trench dielectric-isolation (TD) which enables integration of various devices in an integrated circuit (IC) while avoiding parasitic miss operations by ideal isolation. The structures of the SOI layer and TD, are optimized for obtaining desired device characteristics and high electromagnetic interference (EMI) immunity. While performing all the air bag system functions over a wide range of supply voltage, and ambient temperature, the resulting single chip reduces the electronic parts to about a half of those in the conventional air bags. The combination of single chip oriented circuits and thick SOI-BiCDMOS technologies offered in this work is valuable for size reduction and improved reliability of automotive electronic control units (ECUs).

A novel active-passive sampling approach for measuring time-averaged concentrations of pollutants in water.

PubMed

Amato, Elvio D; Covaci, Adrian; Town, Raewyn M; Hereijgers, Jonas; Bellekens, Ben; Giacometti, Valentina; Breugelmans, Tom; Weyn, Maarten; Dardenne, Freddy; Bervoets, Lieven; Blust, Ronny

2018-06-14

Passive sampling with in situ devices offers several advantages over traditional sampling methods (i.e., discrete spot sampling), however, data interpretation from conventional passive samplers is hampered by difficulties in estimating the thickness of the diffusion layer at the sampler/medium interface (δ), often leading to inaccurate determinations of target analyte concentrations. In this study, the performance of a novel device combining active and passive sampling was investigated in the laboratory. The active-passive sampling (APS) device is comprised of a diffusion cell fitted with a pump and a flowmeter. Three receiving phases traditionally used in passive sampling devices (i.e., chelex resin, Oasis HLB, and silicone rubber), were incorporated in the diffusion cell and allowed the simultaneous accumulation of cationic metals, polar, and non-polar organic compounds, respectively. The flow within the diffusion cell was accurately controlled and monitored, and, combined with diffusion coefficients measurements, enabled the average δ to be estimated. Strong agreement between APS and time-averaged total concentrations measured in discrete water samples was found for most of the substances investigated. Accuracies for metals ranged between 87 and 116%, except Cu and Pb (∼50%), whilst accuracies between 64 and 101%, and 92 and 151% were achieved for polar and non-polar organic compounds, respectively. These results indicate that, via a well-defined in situ preconcentration step, the proposed APS approach shows promise for monitoring the concentration of a range of pollutants in water. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cubic zirconia as a species permeable coating for zinc diffusion in gallium arsenide

NASA Astrophysics Data System (ADS)

Bisberg, J. E.; Dabkowski, F. P.; Chin, A. K.

1988-10-01

Diffusion of zinc into GaAs through an yttria-stabilized cubic zirconia (YSZ) passivation layer has been demonstrated with an open-tube diffusion method. Pure zinc or GaAs/Zn2As3 sources produced high quality planar p-n junctions. The YSZ layer protects the GaAs surface from excessive loss of arsenic, yet is permeable to zinc, allowing its diffusion into the semiconductor. The YSZ films, deposited by electron beam evaporation, were typically 2000 Å thick. Zinc diffusion coefficients (DT) at 650 °C in the YSZ passivated GaAs ranged from 3.6×10-10 cm2/min for the GaAs/Zn2As3 source to 1.9×10-9 cm2/min for the pure zinc source. Doping concentrations for both YSZ passivated and uncapped samples were approximately 5×1019 cm-3.

Preliminary assessment of using tree-tissue analysis and passive-diffusion samplers to evaluate trichloroethene contamination of ground water at Site SS-34N, McChord Air Force Base, Washington, 2001

USGS Publications Warehouse

Cox, S.E.

2002-01-01

Two low-cost innovative sampling procedures for characterizing trichloroethene (TCE) contamination in ground water were evaluated for use at McChord Air Force Base (AFB) by the U.S. Geological Survey, in cooperation with the U.S. Air Force McChord Air Force Base Installation Restoration Program, in 2001. Previous attempts to characterize the source of ground-water contamination in the heterogeneous glacial outwash aquifer at McChord site SS-34N using soil-gas surveys, direct-push exploration, and more than a dozen ground-water monitoring wells have had limited success. The procedures assessed in this study involved analysis of tree-tissue samples to map underlying ground-water contamination and deploying passive-diffusion samplers to measure TCE concentrations in existing monitoring wells. These procedures have been used successfully at other U.S. Department of Defense sites and have resulted in cost avoidance and accelerated site characterization. Despite the presence of TCE in ground water at site SS-34N, TCE was not detected in any of the 20 trees sampled at the site during either early spring or late summer sampling. The reason the tree tissue procedure was not successful at the McChord AFB site SS-34N may have been due to an inability of tree roots to extract moisture from a water table 30 feet below the land surface, or that concentrations of TCE in ground water were not large enough to be detectable in the tree tissue at the sampling point. Passive-diffusion samplers were placed near the top, middle, and bottom of screened intervals in three monitoring wells and TCE was observed in all samplers. Concentrations of TCE from the passive-diffusion samplers were generally similar to concentrations found in samples collected in the same wells using conventional pumping methods. In contrast to conventional pumping methods, the collection of ground-water samples using the passive-diffusion samples did not generate waste purge water that would require hazardous-waste disposal. In addition, the results from the passive-diffusion samples may show that TCE concentrations are stratified across some screened intervals. The overall results of the limited test of passive-diffusion samplers at site SS-34N were similar to more detailed tests conducted at other contaminated sites across the country and indicate that further evaluation of the use of passive-diffusion samplers at McChord site SS-34N is warranted.

Turbulent transport of a passive-scalar field by using a renormalization-group method

NASA Technical Reports Server (NTRS)

Hossain, Murshed

1992-01-01

A passive-scalar field is considered to evolve under the influence of a turbulent fluid governed by the Navier-Stokes equation. Turbulent-transport coefficients are calculated by small-scale elimination using a renormalization-group method. Turbulent processes couple both the viscosity and the diffusivity. In the absence of any correlation between the passive-scalar fluctuations and any component of the fluid velocity, the renormalized diffusivity is essentially the same as if the fluid velocity were frozen, although the renormalized equation does contain higher-order nonlinear terms involving viscosity. This arises due to the nonlinear interaction of the velocity with itself. In the presence of a finite correlation, the turbulent diffusivity becomes coupled with both the velocity field and the viscosity. There is then a dependence of the turbulent decay of the passive scalar on the turbulent Prandtl number.

Gas-diffusion-based passive sampler for ammonia monitoring in marine waters.

PubMed

O'Connor Šraj, Lenka; Almeida, M Inês G S; Bassett, Chelsea; McKelvie, Ian D; Kolev, Spas D

2018-05-01

A novel passive sampler based on gas-diffusion across a hydrophobic membrane is described for the determination of the time-weighted average concentration of dissolved molecular ammonia in high ionic strength aquatic environments, such as sea, coastal and estuarine waters, for a period of 3 days. The passive sampler developed is cheap, easy-to-use, reusable, and has a dynamic concentration range of 2.0-12µM, which covers the water quality guideline trigger value of 11.4µM (160µgL -1 NH 3 -N) for high conservation value waters, making this a powerful new tool for water quality managers involved in long-term ammonia monitoring. The gas-diffusion-based passive sampler was calibrated under laboratory conditions and deployed in a tank of seawater in the laboratory and at an estuarine site for proof of concept, and a good agreement between passive and spot sampling was achieved in both cases. Copyright © 2017 Elsevier B.V. All rights reserved.

Carrier characteristics influence the kinetics of passive drug loading into lipid nanoemulsions.

PubMed

Göke, Katrin; Bunjes, Heike

2018-05-01

Passive loading as a novel screening approach is a material-saving tool for the efficient selection of a suitable colloidal lipid carrier system for poorly water soluble drug candidates. This method comprises incubation of preformed carrier systems with drug powder and subsequent determination of the resulting drug load of the carrier particles after removal of excess drug. For reliable routine use and to obtain meaningful loading results, information on the kinetics of the process is required. Passive loading proceeds via a dissolution-diffusion-based mechanism, where drug surface area and drug water solubility are key parameters for fast passive loading. While the influence of the drug characteristics is mostly understood, the influence of the carrier characteristics remains unknown. The aim of this study was to examine how the lipid nanocarriers' characteristics, i.e. the type of lipid, the lipid content and the particle size, influence the kinetics of passive loading. Fenofibrate was used as model drug and the loading progress was analyzed by UV spectroscopy. The saturation solubility in the nanocarrier particles, i.e. the lipid type, did not influence the passive loading rate constant. Low lipid content in the nanocarrier and a small nanocarrier particle size both increased passive loading speed. Both variations increase the diffusivity of the nanocarrier particles, which is the primary cause for fast loading at these conditions: The quicker the carrier particles diffuse, the higher is the speed of passive loading. The influence of the diffusivity of the lipid nanocarriers and the effect of drug dissolution rate were included in an overall mechanistic model developed for similar processes (A. Balakrishnan, B.D. Rege, G.L. Amidon, J.E. Polli, Surfactant-mediated dissolution: contributions of solubility enhancement and relatively low micelle diffusivity, J. Pharm. Sci. 93 (2004) 2064-2075). The resulting mechanistic model gave a good estimate of the speed of passive loading in nanoemulsions. Whilst the drug's characteristics - apart from drug surface area - are basically fixed, the lipid nanocarriers can be customized to improve passive loading speed, e.g. by using small nanocarrier particles. The knowledge of the loading mechanism now allows the use of passive loading for the straightforward, material-saving selection of suitable lipid drug nanocarriers. Copyright © 2017 Elsevier B.V. All rights reserved.

Record Charge Carrier Diffusion Length in Colloidal Quantum Dot Solids via Mutual Dot-To-Dot Surface Passivation.

PubMed

Carey, Graham H; Levina, Larissa; Comin, Riccardo; Voznyy, Oleksandr; Sargent, Edward H

2015-06-03

Through a combination of chemical and mutual dot-to-dot surface passivation, high-quality colloidal quantum dot solids are fabricated. The joint passivation techniques lead to a record diffusion length for colloidal quantum dots of 230 ± 20 nm. The technique is applied to create thick photovoltaic devices that exhibit high current density without losing fill factor. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

H2S Loss through Nalophan™ Bags: Contributions of Adsorption and Diffusion

PubMed Central

2017-01-01

Hydrogen-sulfide (H2S) is a molecule of small dimensions typically present in the odor emissions from different plants. The European Standard EN 13725:2003 set a maximum storage time allowed of 30 hours, during which the sampling bag has to maintain the mixture of odorants with minimal changes. This study investigates the H2S losses through Nalophan bags and it shows that nonnegligible losses of H2S can be observed. The percent H2S loss after 30 hrs with respect to the initial concentration is equal to 33%  ± 3% at a relative humidity of 20% and equal to 22%  ± 1% at a relative humidity of 60%. The average quantity of adsorbed H2S at 30 h is equal to 2.17 105 gH2S/gNalophan at a storage humidity of 20% and equal to 1.79 105 gH2S/gNalophan at a storage humidity of 60%. The diffusion coefficients of H2S through Nalophan, for these two humidity conditions tested, are comparable (i.e., 7.5 10−12 m2/sec at 20% humidity and 6.6 10−12 m2/sec at 60% humidity). PMID:28740857

Lunar surface vehicle model competition

NASA Technical Reports Server (NTRS)

1990-01-01

During Fall and Winter quarters, Georgia Tech's School of Mechanical Engineering students designed machines and devices related to Lunar Base construction tasks. These include joint projects with Textile Engineering students. Topics studied included lunar environment simulator via drop tower technology, lunar rated fasteners, lunar habitat shelter, design of a lunar surface trenching machine, lunar support system, lunar worksite illumination (daytime), lunar regolith bagging system, sunlight diffusing tent for lunar worksite, service apparatus for lunar launch vehicles, lunar communication/power cables and teleoperated deployment machine, lunar regolith bag collection and emplacement device, soil stabilization mat for lunar launch/landing site, lunar rated fastening systems for robotic implementation, lunar surface cable/conduit and automated deployment system, lunar regolith bagging system, and lunar rated fasteners and fastening systems. A special topics team of five Spring quarter students designed and constructed a remotely controlled crane implement for the SKITTER model.

Passivity analysis for uncertain BAM neural networks with time delays and reaction-diffusions

NASA Astrophysics Data System (ADS)

Zhou, Jianping; Xu, Shengyuan; Shen, Hao; Zhang, Baoyong

2013-08-01

This article deals with the problem of passivity analysis for delayed reaction-diffusion bidirectional associative memory (BAM) neural networks with weight uncertainties. By using a new integral inequality, we first present a passivity condition for the nominal networks, and then extend the result to the case with linear fractional weight uncertainties. The proposed conditions are expressed in terms of linear matrix inequalities, and thus can be checked easily. Examples are provided to demonstrate the effectiveness of the proposed results.

Error in measuring radon in soil gas by means of passive detectors

USGS Publications Warehouse

Tanner, A.B.

1991-01-01

Passive detection of radon isotopes depends on diffusion of radon atoms from the sites of their generation to the location of the detecting or collecting device. Because some radon decays en route to a passive detector in soil, the radon concentration measured by the detector must be less than the concentration in those soil pores where it is undiminished by diffusion to the detector cavity. The true radon concentration may be significantly underestimated in moist soils. -Author

Passive scalars: Mixing, diffusion, and intermittency in helical and nonhelical rotating turbulence

NASA Astrophysics Data System (ADS)

Imazio, P. Rodriguez; Mininni, P. D.

2017-03-01

We use direct numerical simulations to compute structure functions, scaling exponents, probability density functions, and effective transport coefficients of passive scalars in turbulent rotating helical and nonhelical flows. We show that helicity affects the inertial range scaling of the velocity and of the passive scalar when rotation is present, with a spectral law consistent with ˜k⊥-1.4 for the passive scalar variance spectrum. This scaling law is consistent with a phenomenological argument [P. Rodriguez Imazio and P. D. Mininni, Phys. Rev. E 83, 066309 (2011), 10.1103/PhysRevE.83.066309] for rotating nonhelical flows, which follows directly from Kolmogorov-Obukhov scaling and states that if energy follows a E (k ) ˜k-n law, then the passive scalar variance follows a law V (k ) ˜k-nθ with nθ=(5 -n ) /2 . With the second-order scaling exponent obtained from this law, and using the Kraichnan model, we obtain anomalous scaling exponents for the passive scalar that are in good agreement with the numerical results. Multifractal intermittency models are also considered. Intermittency of the passive scalar is stronger than in the nonhelical rotating case, a result that is also confirmed by stronger non-Gaussian tails in the probability density functions of field increments. Finally, Fick's law is used to compute the effective diffusion coefficients in the directions parallel and perpendicular to rotation. Calculations indicate that horizontal diffusion decreases in the presence of helicity in rotating flows, while vertical diffusion increases. A simple mean field argument explains this behavior in terms of the amplitude of velocity fluctuations.

High-resolution passive sampling of dissolved methane in the water column of lakes in Greenland

NASA Astrophysics Data System (ADS)

Goldman, A. E.; Cadieux, S. B.; White, J. R.; Pratt, L. M.

2013-12-01

Arctic lakes are important participants in the global carbon cycle, releasing methane in a warming climate and contributing to a positive feedback to climate change. In order to yield detailed methane budgets and understand the implications of warming on methane dynamics, high-resolution profiles revealing methane behavior within the water column need to be obtained. Single day sampling using disruptive techniques has the potential to result in biases. In order to obtain high-resolution, undisturbed profiles of methane concentration and isotopic composition, this study evaluates a passive sampling method over a multi-day equilibration period. Selected for this study were two small lakes (<1km2) within a narrow valley stretching between Russells Glacier and Søndre Strømfjord in southwestern Greenland, which are part of an ongoing study of a series of seven lakes. Commercially available, 150 mL, polyethylene Passive Diffusion Bags (PDB's) were deployed in July 2013 for five days at 0.5-meter depth intervals. PDB samples were compared to samples collected with a submersible, electric pump taken immediately before PBD deployment. Preliminary CH4 concentrations and carbon isotopes for one lake were obtained in the field using a Los Gatos Research Methane Carbon Isotope Analyzer. PDB sampling and pump sampling resulted in statistically similar concentrations (R2=0.89), ranging from 0.85 to 135 uM from PDB and 0.74 to 143 uM from pump sampling. In anoxic waters of the lake, where concentrations were high enough to yield robust isotopic results on the LGR MCIA, δ13C were also similar between the two methods, yielding -73‰ from PDB and -74‰ from pump sampling. Further investigation will produce results for a second lake and methane carbon and hydrogen isotopic composition for both lakes. Preliminary results for this passive sampling method are promising. We envision the use of this technique in future studies of dissolved methane and expect that it will provide a more finely resolved vertical profile, allowing for a more complete understanding of lacustrine methane dynamics.

Temperature, Oxygen, and Salt-Sensing Neurons in C. elegans Are Carbon Dioxide Sensors that Control Avoidance Behavior

PubMed Central

Bretscher, Andrew Jonathan; Kodama-Namba, Eiji; Busch, Karl Emanuel; Murphy, Robin Joseph; Soltesz, Zoltan; Laurent, Patrick; de Bono, Mario

2011-01-01

Summary Homeostatic control of body fluid CO2 is essential in animals but is poorly understood. C. elegans relies on diffusion for gas exchange and avoids environments with elevated CO2. We show that C. elegans temperature, O2, and salt-sensing neurons are also CO2 sensors mediating CO2 avoidance. AFD thermosensors respond to increasing CO2 by a fall and then rise in Ca2+ and show a Ca2+ spike when CO2 decreases. BAG O2 sensors and ASE salt sensors are both activated by CO2 and remain tonically active while high CO2 persists. CO2-evoked Ca2+ responses in AFD and BAG neurons require cGMP-gated ion channels. Atypical soluble guanylate cyclases mediating O2 responses also contribute to BAG CO2 responses. AFD and BAG neurons together stimulate turning when CO2 rises and inhibit turning when CO2 falls. Our results show that C. elegans senses CO2 using functionally diverse sensory neurons acting homeostatically to minimize exposure to elevated CO2. PMID:21435556

Scaling laws of passive-scalar diffusion in the interstellar medium

NASA Astrophysics Data System (ADS)

Colbrook, Matthew J.; Ma, Xiangcheng; Hopkins, Philip F.; Squire, Jonathan

2017-05-01

Passive-scalar mixing (metals, molecules, etc.) in the turbulent interstellar medium (ISM) is critical for abundance patterns of stars and clusters, galaxy and star formation, and cooling from the circumgalactic medium. However, the fundamental scaling laws remain poorly understood in the highly supersonic, magnetized, shearing regime relevant for the ISM. We therefore study the full scaling laws governing passive-scalar transport in idealized simulations of supersonic turbulence. Using simple phenomenological arguments for the variation of diffusivity with scale based on Richardson diffusion, we propose a simple fractional diffusion equation to describe the turbulent advection of an initial passive scalar distribution. These predictions agree well with the measurements from simulations, and vary with turbulent Mach number in the expected manner, remaining valid even in the presence of a large-scale shear flow (e.g. rotation in a galactic disc). The evolution of the scalar distribution is not the same as obtained using simple, constant 'effective diffusivity' as in Smagorinsky models, because the scale dependence of turbulent transport means an initially Gaussian distribution quickly develops highly non-Gaussian tails. We also emphasize that these are mean scalings that apply only to ensemble behaviours (assuming many different, random scalar injection sites): individual Lagrangian 'patches' remain coherent (poorly mixed) and simply advect for a large number of turbulent flow-crossing times.

Evidence for equivalence of diffusion processes of passive scalar and magnetic fields in anisotropic Navier-Stokes turbulence.

PubMed

Jurčišinová, E; Jurčišin, M

2017-05-01

The influence of the uniaxial small-scale anisotropy on the kinematic magnetohydrodynamic turbulence is investigated by using the field theoretic renormalization group technique in the one-loop approximation of a perturbation theory. The infrared stable fixed point of the renormalization group equations, which drives the scaling properties of the model in the inertial range, is investigated as the function of the anisotropy parameters and it is shown that, at least at the one-loop level of approximation, the diffusion processes of the weak passive magnetic field in the anisotropically driven kinematic magnetohydrodynamic turbulence are completely equivalent to the corresponding diffusion processes of passively advected scalar fields in the anisotropic Navier-Stokes turbulent environments.

Multi-layer light-weight protective coating and method for application

NASA Technical Reports Server (NTRS)

Wiedemann, Karl E. (Inventor); Clark, Ronald K. (Inventor); Taylor, Patrick J. (Inventor)

1992-01-01

A thin, light-weight, multi-layer coating is provided for protecting metals and their alloys from environmental attack at high temperatures. A reaction barrier is applied to the metal substrate and a diffusion barrier is then applied to the reaction barrier. A sealant layer may also be applied to the diffusion barrier if desired. The reaction barrier is either non-reactive or passivating with respect to the metal substrate and the diffusion barrier. The diffusion barrier is either non-reactive or passivating with respect to the reaction barrier and the sealant layer. The sealant layer is immiscible with the diffusion barrier and has a softening point below the expected use temperature of the metal.

Commercially Available Gas-Permeable Cell Culture Bags May Not Prevent Anoxia in Cultured or Shipped Islets

PubMed Central

Avgoustiniatos, E.S.; Hering, B.J.; Rozak, P.R.; Wilson, J.R.; Tempelman, L.A.; Balamurugan, A.N.; Welch, D.P.; Weegman, B.P.; Suszynski, T.M.; Papas, K.K.

2009-01-01

Prolonged anoxia has deleterious effects on islets. Gas-permeable cell culture devices can be used to minimize anoxia during islet culture and especially during shipment when elimination of gas-liquid interfaces is required to prevent the formation of damaging gas bubbles. Gas-permeable bags may have several drawbacks, such as propensity for puncture and contamination, difficult islet retrieval, and significantly lower oxygen permeability than silicone rubber membranes (SRM). We hypothesized that oxygen permeability of bags may be insufficient for islet oxygenation. We measured oxygen transmission rates through the membrane walls of three different types of commercially available bags and through SRM currently used for islet shipment. We found that the bag membranes have oxygen transmission rates per unit area about 100-fold lower than SRM. We solved the oxygen diffusion-reaction equation for 150-μm diameter islets seeded at 3000 islet equivalents per cm2, a density adequate to culture and ship an entire human or porcine islet preparation in a single gas-permeable device, predicting that about 40% of the islet volume would be anoxic at 22°C and about 70% would be anoxic at 37°C. Islets of larger size or islets accumulated during shipment would be even more anoxic. The model predicted no anoxia in islets similarly seeded in devices with SRM bottoms. We concluded that commercially available bags may not prevent anoxia during islet culture or shipment; devices with SRM bottoms are more suitable alternatives. PMID:18374080

Two-dimensional numerical simulation of boron diffusion for pyramidally textured silicon

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

Ma, Fa-Jun, E-mail: Fajun.Ma@nus.edu.sg; Duttagupta, Shubham; Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, 117576

2014-11-14

Multidimensional numerical simulation of boron diffusion is of great relevance for the improvement of industrial n-type crystalline silicon wafer solar cells. However, surface passivation of boron diffused area is typically studied in one dimension on planar lifetime samples. This approach neglects the effects of the solar cell pyramidal texture on the boron doping process and resulting doping profile. In this work, we present a theoretical study using a two-dimensional surface morphology for pyramidally textured samples. The boron diffusivity and segregation coefficient between oxide and silicon in simulation are determined by reproducing measured one-dimensional boron depth profiles prepared using different boronmore » diffusion recipes on planar samples. The established parameters are subsequently used to simulate the boron diffusion process on textured samples. The simulated junction depth is found to agree quantitatively well with electron beam induced current measurements. Finally, chemical passivation on planar and textured samples is compared in device simulation. Particularly, a two-dimensional approach is adopted for textured samples to evaluate chemical passivation. The intrinsic emitter saturation current density, which is only related to Auger and radiative recombination, is also simulated for both planar and textured samples. The differences between planar and textured samples are discussed.« less

Assessment of species-specific and temporal variations of major, trace and rare earth elements in vineyard ambient using moss bags.

PubMed

Milićević, Tijana; Aničić Urošević, Mira; Vuković, Gordana; Škrivanj, Sandra; Relić, Dubravka; Frontasyeva, Marina V; Popović, Aleksandar

2017-10-01

Since the methodological parameters of moss bag biomonitoring have rarely been investigated for the application in agricultural areas, two mosses, Sphagnum girgensohnii (a species of the most recommended biomonitoring genus) and Hypnum cupressiforme (commonly available), were verified in a vineyard ambient. The moss bags were exposed along transects in six vineyard parcels during the grapevine season (March‒September 2015). To select an appropriate period for the reliable 'signal' of the element enrichment in the mosses, the bags were simultaneously exposed during five periods (3 × 2 months, 1 × 4 months, and 1 × 6 months). Assuming that vineyard is susceptible to contamination originated from different agricultural treatments, a wide range of elements (41) were determined in the moss and topsoil samples. The mosses were significantly enriched by the elements during the 2-month bag exposure which gradually increasing up to 6 months, but Cu and Ni exhibited the noticeable fluctuations during the grapevine season. However, the 6-month exposure of moss bags could be recommended for comparative studies among different vineyards because it reflects the ambient pollution comprising unpredictable treatments of grapevine applied during the whole season. Although higher element concentrations were determined in S. girgensohnii than H. cupressiforme, both species reflected the spatio-temporal changes in the ambient element content. Moreover, the significant correlation of the element (Cr, Cu, Sb, and Ti) concentrations between the mosses, and the same pairs of the elements correlated within the species, imply the comparable use of S. girgensohnii and H. cupressiforme in the vineyard (agricultural) ambient. Finally, both the moss bags and the soil analyses suggest that vineyard represents a dominant diffuse pollution source of As, Cr, Cu, Ni, Fe, and V. Copyright © 2017 Elsevier Inc. All rights reserved.

Measurement of Passive Uptake Rates for Volatile Organic Compounds on Commercial Thermal Desorption Tubes and the Effect of Ozone on Sampling

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

Maddalena, Randy; Parra, Amanda; Russell, Marion

Diffusive or passive sampling methods using commercially filled axial-sampling thermal desorption tubes are widely used for measuring volatile organic compounds (VOCs) in air. The passive sampling method provides a robust, cost effective way to measure air quality with time-averaged concentrations spanning up to a week or more. Sampling rates for VOCs can be calculated using tube geometry and Fick’s Law for ideal diffusion behavior or measured experimentally. There is evidence that uptake rates deviate from ideal and may not be constant over time. Therefore, experimentally measured sampling rates are preferred. In this project, a calibration chamber with a continuous stirredmore » tank reactor design and constant VOC source was combined with active sampling to generate a controlled dynamic calibration environment for passive samplers. The chamber air was augmented with a continuous source of 45 VOCs ranging from pentane to diethyl phthalate representing a variety of chemical classes and physiochemical properties. Both passive and active samples were collected on commercially filled Tenax TA thermal desorption tubes over an 11-day period and used to calculate passive sampling rates. A second experiment was designed to determine the impact of ozone on passive sampling by using the calibration chamber to passively load five terpenes on a set of Tenax tubes and then exposing the tubes to different ozone environments with and without ozone scrubbers attached to the tube inlet. During the sampling rate experiment, the measured diffusive uptake was constant for up to seven days for most of the VOCs tested but deviated from linearity for some of the more volatile compounds between seven and eleven days. In the ozone experiment, both exposed and unexposed tubes showed a similar decline in terpene mass over time indicating back diffusion when uncapped tubes were transferred to a clean environment but there was no indication of significant loss by ozone reaction.« less

Coupling of active motion and advection shapes intracellular cargo transport.

PubMed

Khuc Trong, Philipp; Guck, Jochen; Goldstein, Raymond E

2012-07-13

Intracellular cargo transport can arise from passive diffusion, active motor-driven transport along cytoskeletal filament networks, and passive advection by fluid flows entrained by such cargo-motor motion. Active and advective transport are thus intrinsically coupled as related, yet different representations of the same underlying network structure. A reaction-advection-diffusion system is used here to show that this coupling affects the transport and localization of a passive tracer in a confined geometry. For sufficiently low diffusion, cargo localization to a target zone is optimized either by low reaction kinetics and decoupling of bound and unbound states, or by a mostly disordered cytoskeletal network with only weak directional bias. These generic results may help to rationalize subtle features of cytoskeletal networks, for example as observed for microtubules in fly oocytes.

Major diffusion leaks of clamp-on leaf cuvettes still unaccounted: how erroneous are the estimates of Farquhar et al. model parameters?

PubMed

Rodeghiero, Mirco; Niinemets, Ulo; Cescatti, Alessandro

2007-08-01

Estimates of leaf gas-exchange characteristics using standard clamp-on leaf chambers are prone to errors because of diffusion leaks. While some consideration has been given to CO(2) diffusion leaks, potential water vapour diffusion leaks through chamber gaskets have been neglected. We estimated diffusion leaks of two clamp-on Li-Cor LI-6400 (Li-Cor, Inc., Lincoln, NE, USA) leaf chambers with polymer foam gaskets and enclosing either 2 or 6 cm(2) leaf area, and conducted a sensitivity analysis of the diffusion leak effects on Farquhar et al. photosynthesis model parameters - the maximum carboxylase activity of ribulose 1 x 5-bisphosphate carboxylase/oxygenase (Rubisco) (V(cmax)), capacity for photosynthetic electron transport (J(max)) and non-photorespiratory respiration rate in light (R(d)). In addition, net assimilation rate (A(n)) versus intercellular CO(2) (C(i)) responses were measured in leaves of Mediterranean evergreen species Quercus ilex L. enclosing the whole leaf chamber in a polyvinyl fluoride bag flushed with the exhaust air of leaf chamber, thereby effectively reducing the CO(2) and water vapour gradients between ambient air and leaf chamber. For the empty chambers, average diffusion leak for CO(2), K(CO2), (molar flow rate corresponding to unit CO(2) mole fraction difference) was ca. 0.40 micromol s(-1). K(CO2) increased ca. 50% if a dead leaf was clamped between the leaf chamber. Average diffusion leak for H(2)O was ca. 5- to 10-fold larger than the diffusion leak for CO(2). Sensitivity analyses demonstrated that the consequence of a CO(2) diffusion leak was apparent enhancement of A(n) at high CO(2) mole fraction and reduction at lower CO(2) mole fraction, and overall compression of C(i) range. As the result of these modifications, Farquhar et al. model parameters were overestimated. The degree of overestimation increased in the order of V(cmax) < J(max) < R(d), and was larger for smaller chambers and for leaves with lower photosynthetic capacity, leading to overestimation of all three parameters by 70-290% for 2 cm(2), and by 10-60% for 6 cm(2) chamber. Significant diffusion corrections (5-36%) were even required for leaves with high photosynthetic capacity measured in largest chamber. Water vapour diffusion leaks further enhanced the overestimation of model parameters. For small chambers and low photosynthetic capacities, apparent C(i) was simulated to decrease with increasing A(n) because of simultaneous CO(2) and H(2)O diffusion leaks. Measurements in low photosynthetic capacity Quercus ilex leaves enclosed in 2 cm(2) leaf chamber exhibited negative apparent C(i) values at highest A(n). For the same leaves measured with the entire leaf chamber enclosed in the polyvinyl fluoride bag, C(i) and A(n) increased monotonically. While the measurements without the bag could be corrected for diffusion leaks, the required correction in A(n) and transpiration rates was 100-500%, and there was large uncertainty in Farquhar et al. model parameters derived from 'corrected'A(n)/C(i) response curves because of uncertainties in true diffusion leaks. These data demonstrate that both CO(2) and water vapour diffusion leaks need consideration in measurements with clamp-on leaf cuvettes. As plants in natural environments are often characterized by low photosynthetic capacities, cuvette designs need to be improved for reliable measurements in such species.

Temperature, oxygen, and salt-sensing neurons in C. elegans are carbon dioxide sensors that control avoidance behavior.

PubMed

Bretscher, Andrew Jonathan; Kodama-Namba, Eiji; Busch, Karl Emanuel; Murphy, Robin Joseph; Soltesz, Zoltan; Laurent, Patrick; de Bono, Mario

2011-03-24

Homeostatic control of body fluid CO(2) is essential in animals but is poorly understood. C. elegans relies on diffusion for gas exchange and avoids environments with elevated CO(2). We show that C. elegans temperature, O(2), and salt-sensing neurons are also CO(2) sensors mediating CO(2) avoidance. AFD thermosensors respond to increasing CO(2) by a fall and then rise in Ca(2+) and show a Ca(2+) spike when CO(2) decreases. BAG O(2) sensors and ASE salt sensors are both activated by CO(2) and remain tonically active while high CO(2) persists. CO(2)-evoked Ca(2+) responses in AFD and BAG neurons require cGMP-gated ion channels. Atypical soluble guanylate cyclases mediating O(2) responses also contribute to BAG CO(2) responses. AFD and BAG neurons together stimulate turning when CO(2) rises and inhibit turning when CO(2) falls. Our results show that C. elegans senses CO(2) using functionally diverse sensory neurons acting homeostatically to minimize exposure to elevated CO(2). Copyright © 2011 Elsevier Inc. All rights reserved.

An augmented aging process in brain white matter in HIV.

PubMed

Kuhn, Taylor; Kaufmann, Tobias; Doan, Nhat Trung; Westlye, Lars T; Jones, Jacob; Nunez, Rodolfo A; Bookheimer, Susan Y; Singer, Elyse J; Hinkin, Charles H; Thames, April D

2018-06-01

HIV infection and aging are both associated with neurodegeneration. However, whether the aging process alone or other factors associated with advanced age account for the progression of neurodegeneration in the aging HIV-positive (HIV+) population remains unclear. HIV+ (n = 70) and HIV-negative (HIV-, n = 34) participants underwent diffusion tensor imaging (DTI) and metrics of microstructural properties were extracted from regions of interest (ROIs). A support vector regression model was trained on two independent datasets of healthy adults across the adult life-span (n = 765, Cam-CAN = 588; UiO = 177) to predict participant age from DTI metrics, and applied to the HIV dataset. Predicted brain age gap (BAG) was computed as the difference between predicted age and chronological age, and statistically compared between HIV groups. Regressions assessed the relationship between BAG and HIV severity/medical comorbidities. Finally, correlation analyses tested for associations between BAG and cognitive performance. BAG was significantly higher in the HIV+ group than the HIV- group F (1, 103) = 12.408, p = .001). HIV RNA viral load was significantly associated with BAG, particularly in older HIV+ individuals (R 2  = 0.29, F(7, 70) = 2.66, p = .021). Further, BAG was negatively correlated with domain-level cognitive function (learning: r = -0.26, p = .008; memory: r = -0.21, p = .034). HIV infection is associated with augmented white matter aging, and greater brain aging is associated with worse cognitive performance in multiple domains. © 2018 Wiley Periodicals, Inc.

Carrier-Mediated Cocaine Transport at the Blood-Brain Barrier as a Putative Mechanism in Addiction Liability

PubMed Central

Chapy, Hélène; Smirnova, Maria; André, Pascal; Schlatter, Joël; Chiadmi, Fouad; Couraud, Pierre-Olivier; Scherrmann, Jean-Michel; Declèves, Xavier

2015-01-01

Background: The rate of entry of cocaine into the brain is a critical factor that influences neuronal plasticity and the development of cocaine addiction. Until now, passive diffusion has been considered the unique mechanism known by which cocaine crosses the blood-brain barrier. Methods: We reassessed mechanisms of transport of cocaine at the blood-brain barrier using a human cerebral capillary endothelial cell line (hCMEC/D3) and in situ mouse carotid perfusion. Results: Both in vivo and in vitro cocaine transport studies demonstrated the coexistence of a carrier-mediated process with passive diffusion. At pharmacological exposure level, passive diffusion of cocaine accounted for only 22.5% of the total cocaine influx in mice and 5.9% in hCMEC/D3 cells, whereas the carrier-mediated influx rate was 3.4 times greater than its passive diffusion rate in vivo. The functional identification of this carrier-mediated transport demonstrated the involvement of a proton antiporter that shared the properties of the previously characterized clonidine and nicotine transporter. The functionnal characterization suggests that the solute carrier (SLC) transporters Oct (Slc22a1-3), Mate (Slc47a1) and Octn (Slc22a4-5) are not involved in the cocaine transport in vivo and in vitro. Diphenhydramine, heroin, tramadol, cocaethylene, and norcocaine all strongly inhibited cocaine transport, unlike benzoylecgonine. Trans-stimulation studies indicated that diphenhydramine, nicotine, 3,4-methylenedioxyamphetamine (ecstasy) and the cathinone compound 3,4-methylenedioxypyrovalerone (MDPV) were also substrates of the cocaine transporter. Conclusions: Cocaine transport at the BBB involves a proton-antiporter flux that is quantitatively much more important than its passive diffusion. The molecular identification and characterization of this transporter will provide new tools to understand its role in addictive mechanisms. PMID:25539501

Effective Drug Delivery in Diffuse Intrinsic Pontine Glioma: A Theoretical Model to Identify Potential Candidates

PubMed Central

El-Khouly, Fatma E.; van Vuurden, Dannis G.; Stroink, Thom; Hulleman, Esther; Kaspers, Gertjan J. L.; Hendrikse, N. Harry; Veldhuijzen van Zanten, Sophie E. M.

2017-01-01

Despite decades of clinical trials for diffuse intrinsic pontine glioma (DIPG), patient survival does not exceed 10% at two years post-diagnosis. Lack of benefit from systemic chemotherapy may be attributed to an intact bloodbrain barrier (BBB). We aim to develop a theoretical model including relevant physicochemical properties in order to review whether applied chemotherapeutics are suitable for passive diffusion through an intact BBB or whether local administration via convection-enhanced delivery (CED) may increase their therapeutic potential. Physicochemical properties (lipophilicity, molecular weight, and charge in physiological environment) of anticancer drugs historically and currently administered to DIPG patients, that affect passive diffusion over the BBB, were included in the model. Subsequently, the likelihood of BBB passage of these drugs was ascertained, as well as their potential for intratumoral administration via CED. As only non-molecularly charged, lipophilic, and relatively small sized drugs are likely to passively diffuse through the BBB, out of 51 drugs modeled, only 8 (15%)—carmustine, lomustine, erlotinib, vismodegib, lenalomide, thalidomide, vorinostat, and mebendazole—are theoretically qualified for systemic administration in DIPG. Local administration via CED might create more therapeutic options, excluding only positively charged drugs and drugs that are either prodrugs and/or only available as oral formulation. A wide variety of drugs have been administered systemically to DIPG patients. Our model shows that only few are likely to penetrate the BBB via passive diffusion, which may partly explain the lack of efficacy. Drug distribution via CED is less dependent on physicochemical properties and may increase the therapeutic options for DIPG. PMID:29164054

Body mass scaling of passive oxygen diffusion in endotherms and ectotherms

PubMed Central

Gillooly, James F.; Gomez, Juan Pablo; Mavrodiev, Evgeny V.; Rong, Yue; McLamore, Eric S.

2016-01-01

The area and thickness of respiratory surfaces, and the constraints they impose on passive oxygen diffusion, have been linked to differences in oxygen consumption rates and/or aerobic activity levels in vertebrates. However, it remains unclear how respiratory surfaces and associated diffusion rates vary with body mass across vertebrates, particularly in relation to the body mass scaling of oxygen consumption rates. Here we address these issues by first quantifying the body mass dependence of respiratory surface area and respiratory barrier thickness for a diversity of endotherms (birds and mammals) and ectotherms (fishes, amphibians, and reptiles). Based on these findings, we then use Fick’s law to predict the body mass scaling of oxygen diffusion for each group. Finally, we compare the predicted body mass dependence of oxygen diffusion to that of oxygen consumption in endotherms and ectotherms. We find that the slopes and intercepts of the relationships describing the body mass dependence of passive oxygen diffusion in these two groups are statistically indistinguishable from those describing the body mass dependence of oxygen consumption. Thus, the area and thickness of respiratory surfaces combine to match oxygen diffusion capacity to oxygen consumption rates in both air- and water-breathing vertebrates. In particular, the substantially lower oxygen consumption rates of ectotherms of a given body mass relative to those of endotherms correspond to differences in oxygen diffusion capacity. These results provide insights into the long-standing effort to understand the structural attributes of organisms that underlie the body mass scaling of oxygen consumption. PMID:27118837

Body mass scaling of passive oxygen diffusion in endotherms and ectotherms.

PubMed

Gillooly, James F; Gomez, Juan Pablo; Mavrodiev, Evgeny V; Rong, Yue; McLamore, Eric S

2016-05-10

The area and thickness of respiratory surfaces, and the constraints they impose on passive oxygen diffusion, have been linked to differences in oxygen consumption rates and/or aerobic activity levels in vertebrates. However, it remains unclear how respiratory surfaces and associated diffusion rates vary with body mass across vertebrates, particularly in relation to the body mass scaling of oxygen consumption rates. Here we address these issues by first quantifying the body mass dependence of respiratory surface area and respiratory barrier thickness for a diversity of endotherms (birds and mammals) and ectotherms (fishes, amphibians, and reptiles). Based on these findings, we then use Fick's law to predict the body mass scaling of oxygen diffusion for each group. Finally, we compare the predicted body mass dependence of oxygen diffusion to that of oxygen consumption in endotherms and ectotherms. We find that the slopes and intercepts of the relationships describing the body mass dependence of passive oxygen diffusion in these two groups are statistically indistinguishable from those describing the body mass dependence of oxygen consumption. Thus, the area and thickness of respiratory surfaces combine to match oxygen diffusion capacity to oxygen consumption rates in both air- and water-breathing vertebrates. In particular, the substantially lower oxygen consumption rates of ectotherms of a given body mass relative to those of endotherms correspond to differences in oxygen diffusion capacity. These results provide insights into the long-standing effort to understand the structural attributes of organisms that underlie the body mass scaling of oxygen consumption.

Characterization of the Etna volcanic emissions through an active biomonitoring technique (moss-bags): part 2--morphological and mineralogical features.

PubMed

Calabrese, S; D'Alessandro, W

2015-01-01

Volcanic emissions were studied at Mount Etna (Italy) by using moss-bags technique. Mosses were exposed around the volcano at different distances from the active vents to evaluate the impact of volcanic emissions in the atmosphere. Morphology and mineralogy of volcanic particulate intercepted by mosses were investigated using scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS). Particles emitted during passive degassing activity from the two active vents, Bocca Nuova and North East Crater (BNC and NEC), were identified as silicates, sulfates and halide compounds. In addition to volcanic particles, we found evidences also of geogenic, anthropogenic and marine spray input. The study has shown the robustness of this active biomonitoring technique to collect particles, very useful in active volcanic areas characterized by continuous degassing and often not easily accessible to apply conventional sampling techniques. Copyright © 2014 Elsevier Ltd. All rights reserved.

Study of surface passivation as a function of InP closed-ampoule solar cell fabrication processing variables

NASA Technical Reports Server (NTRS)

Faur, Mircea; Faur, Maria; Jenkins, Phillip; Goradia, Manju; Goradia, Chandra; Bailey, Sheila; Weinberg, Irving; Jayne, Douglas

1990-01-01

The effects of various surface preparation procedures, including chemical treatment and anodic or chemical oxidation, closed-ampoule diffusion conditions, and post-diffusion surface preparation and annealing conditions, on the passivating properties of InP have been investigated in order to optimize the fabrication procedures of n(+)p InP solar cells made by closed-ampoule diffusion of sulfur into p-type InP. The InP substrates used were p-type Cd-doped to a level of 1.7 x 10 to the 16th/cu cm, Zn-doped to levels of 2.2 x 10 to the 16th and 1.2 x 10 to the 18th/cu cm, and n-type S-doped to 4.4 x 10 to the 18th/cu cm. The passivating properties have been evaluated from photoluminescence (PL) and conductance-voltage (G-V) data. Good agreement was found between the level of surface passivation and the composition of different surface layers as revealed by X-ray photoelectron spectroscopy (XPS) analysis.

Biomonitoring of atmospheric pollution by moss bags: Discriminating urban-rural structure in a fragmented landscape.

PubMed

Capozzi, F; Giordano, S; Di Palma, A; Spagnuolo, V; De Nicola, F; Adamo, P

2016-04-01

In this paper we investigated the possibility to use moss bags to detect pollution inputs - metals, metalloids and polycyclic aromatic hydrocarbons (PAHs) - in sites chosen for their different land use (agricultural, urban/residential scenarios) and proximity to roads (sub-scenarios), in a fragmented conurbation of Campania (southern Italy). We focused on thirty-nine elements including rare earths. For most of them, moss uptake was higher in agricultural than in urban scenarios and in front road sites. Twenty PAHs were analyzed in a subset of agricultural sites; 4- and 5-ringed PAHs were the most abundant, particularly chrysene, fluoranthene and pyrene. Overall results indicated that investigated pollutants have a similar spatial distribution pattern over the entire study area, with road traffic and agricultural practices as the major diffuse pollution sources. Moss bags proved a very sensitive tool, able to discriminate between different land use scenarios and proximity to roads in a mixed rural-urban landscape. Copyright © 2016 Elsevier Ltd. All rights reserved.

Passivation of phosphorus diffused silicon surfaces with Al2O3: Influence of surface doping concentration and thermal activation treatments

NASA Astrophysics Data System (ADS)

Richter, Armin; Benick, Jan; Kimmerle, Achim; Hermle, Martin; Glunz, Stefan W.

2014-12-01

Thin layers of Al2O3 are well known for the excellent passivation of p-type c-Si surfaces including highly doped p+ emitters, due to a high density of fixed negative charges. Recent results indicate that Al2O3 can also provide a good passivation of certain phosphorus-diffused n+ c-Si surfaces. In this work, we studied the recombination at Al2O3 passivated n+ surfaces theoretically with device simulations and experimentally for Al2O3 deposited with atomic layer deposition. The simulation results indicate that there is a certain surface doping concentration, where the recombination is maximal due to depletion or weak inversion of the charge carriers at the c-Si/Al2O3 interface. This pronounced maximum was also observed experimentally for n+ surfaces passivated either with Al2O3 single layers or stacks of Al2O3 capped by SiNx, when activated with a low temperature anneal (425 °C). In contrast, for Al2O3/SiNx stacks activated with a short high-temperature firing process (800 °C) a significant lower surface recombination was observed for most n+ diffusion profiles without such a pronounced maximum. Based on experimentally determined interface properties and simulation results, we attribute this superior passivation quality after firing to a better chemical surface passivation, quantified by a lower interface defect density, in combination with a lower density of negative fixed charges. These experimental results reveal that Al2O3/SiNx stacks can provide not only excellent passivation on p+ surfaces but also on n+ surfaces for a wide range of surface doping concentrations when activated with short high-temperature treatments.

Demonstration and Validation of a Regenerated Cellulose Dialysis Membrane Diffusion Sampler for Monitoring Ground Water Quality and Remediation Progress at DoD Sites for Perchlorate and Explosives Compounds (ER-0313)

DTIC Science & Technology

2010-09-30

Inductively coupled plasma – mass spectrometry ITRC Interstate Technology Regulatory Council LRL Laboratory reporting level LDPE Low-density polyethylene...diameter of the well. Another diffusion membrane sampler design consists of a tubular-shaped bag made of flexible low-density polyethylene ( LDPE ...Vroblesky, 2001a, 2001b). The LDPE tube is heat-sealed on one end, filled with high-purity water, heat-sealed at the top, and then suspended in a well to

Sorbent-based sampling methods for volatile and semi-volatile organic compounds in air. Part 2. Sorbent selection and other aspects of optimizing air monitoring methods.

PubMed

Woolfenden, Elizabeth

2010-04-16

Sorbent tubes/traps are widely used in combination with gas chromatographic (GC) analytical methods to monitor the vapour-phase fraction of organic compounds in air. Applications range from atmospheric research and ambient air monitoring (indoor and outdoor) to occupational hygiene (personal exposure assessment) and measuring chemical emission levels. Part 1 of this paper reviewed the main sorbent-based air sampling strategies including active (pumped) tube monitoring, diffusive (passive) sampling onto sorbent tubes/cartridges plus sorbent trapping/focusing of whole air samples that are either collected in containers (such as canisters or bags) or monitored online. Options for subsequent extraction and transfer to GC(MS) analysis were also summarised and the trend to thermal desorption (TD)-based methods and away from solvent extraction was explained. As a result of this trend, demand for TD-compatible sorbents (alternatives to traditional charcoal) is growing. Part 2 of this paper therefore continues with a summary of TD-compatible sorbents, their respective advantages and limitations and considerations for sorbent selection. Other analytical considerations for optimizing sorbent-based air monitoring methods are also discussed together with recent technical developments and sampling accessories which have extended the application range of sorbent trapping technology generally. Copyright 2010 Elsevier B.V. All rights reserved.

Impact of passive and active promotional strategies on patient acceptance of medication therapy management services.

PubMed

Huet, Alison L; Frail, Caitlin K; Lake, Leslie M; Snyder, Margie E

2015-01-01

To assess the impact of passive and active promotional strategies on patient acceptance of medication therapy management (MTM) services, and to identify reasons for patient acceptance or refusal. Four promotional approaches were developed to offer MTM services to eligible patients, including letters and bag stuffers ("passive" approaches), and face-to-face offers and telephone calls ("active" approaches). Thirty pharmacies in a grocery store chain were randomized to one of the four approaches. Patient acceptance rates were compared among the four groups, and between active and passive approaches using hierarchical logistic regression techniques. Depending on their decision to accept or decline the service, patients were invited to take part in one of two brief telephone surveys. No significant differences were identified among the four promotional methods or between active and passive methods in the analyses. Patients' most frequent reasons for accepting MTM services were potential cost savings, review of how the medications were working, the expert opinion of the pharmacist, and education about medications. Patients' most frequent reasons for declining MTM services were that the participant already felt comfortable with their medications and felt their pharmacist provides these services on a regular basis. No significant difference was found among any of the four groups or between active or passive approaches. Further research is warranted to identify strategies for improving patient engagement in MTM services.

Surface modification of closed plastic bags for adherent cell cultivation

NASA Astrophysics Data System (ADS)

Lachmann, K.; Dohse, A.; Thomas, M.; Pohl, S.; Meyring, W.; Dittmar, K. E. J.; Lindenmeier, W.; Klages, C.-P.

2011-07-01

In modern medicine human mesenchymal stem cells are becoming increasingly important. However, a successful cultivation of this type of cells is only possible under very specific conditions. Of great importance, for instance, are the absence of contaminants such as foreign microbiological organisms, i.e., sterility, and the chemical functionalization of the ground on which the cells are grown. As cultivation of these cells makes high demands, a new procedure for cell cultivation has been developed in which closed plastic bags are used. For adherent cell growth chemical functional groups have to be introduced on the inner surface of the plastic bag. This can be achieved by a new, atmospheric-pressure plasma-based method presented in this paper. The method which was developed jointly by the Fraunhofer IST and the Helmholtz HZI can be implemented in automated equipment as is also shown in this contribution. Plasma process gases used include helium or helium-based gas mixtures (He + N2 + H2) and vapors of suitable film-forming agents or precursors such as APTMS, DACH, and TMOS in helium. The effect of plasma treatment is investigated by FTIR-ATR spectroscopy as well as surface tension determination based on contact angle measurements and XPS. Plasma treatment in nominally pure helium increases the surface tension of the polymer foil due to the presence of oxygen traces in the gas and oxygen diffusing through the gas-permeable foil, respectively, reacting with surface radical centers formed during contact with the discharge. Primary amino groups are obtained on the inner surface by treatment in mixtures with nitrogen and hydrogen albeit their amount is comparably small due to diffusion of oxygen through the gas-permeable bag, interfering with the plasma-amination process. Surface modifications introducing amino groups on the inner surface turned out to be most efficient in the promotion of cell growth.

Electrical and optical characterization of surface passivation in GaAs nanowires.

PubMed

Chang, Chia-Chi; Chi, Chun-Yung; Yao, Maoqing; Huang, Ningfeng; Chen, Chun-Chung; Theiss, Jesse; Bushmaker, Adam W; Lalumondiere, Stephen; Yeh, Ting-Wei; Povinelli, Michelle L; Zhou, Chongwu; Dapkus, P Daniel; Cronin, Stephen B

2012-09-12

We report a systematic study of carrier dynamics in Al(x)Ga(1-x)As-passivated GaAs nanowires. With passivation, the minority carrier diffusion length (L(diff)) increases from 30 to 180 nm, as measured by electron beam induced current (EBIC) mapping, and the photoluminescence (PL) lifetime increases from sub-60 ps to 1.3 ns. A 48-fold enhancement in the continuous-wave PL intensity is observed on the same individual nanowire with and without the Al(x)Ga(1-x)As passivation layer, indicating a significant reduction in surface recombination. These results indicate that, in passivated nanowires, the minority carrier lifetime is not limited by twin stacking faults. From the PL lifetime and minority carrier diffusion length, we estimate the surface recombination velocity (SRV) to range from 1.7 × 10(3) to 1.1 × 10(4) cm·s(-1), and the minority carrier mobility μ is estimated to lie in the range from 10.3 to 67.5 cm(2) V(-1) s(-1) for the passivated nanowires.

Passive sampler for PM10-2.5 aerosol.

PubMed

Leith, David; Sommerlatt, Darrell; Boundy, Maryanne G

2007-03-01

This study investigates the use of a small passive sampler for aerosol particles to determine particulate matter (PM)10-2.5 concentrations in outdoor air. The passive sampler collects particles by gravity, diffusion, and convective diffusion onto a glass coverslip that is then examined with an optical microscope; digital images are processed with free software and the resultant PM10-2.5 concentrations determined. Both the samplers and the analyses are relatively inexpensive. Passive samplers were collocated with Federal Reference Method (FRM) samplers in Chapel Hill, NC; Phoenix, AZ; and Birmingham, AL; for periods from 5 to 15 days. Particles consisted primarily of inorganic dusts at some sites and a mix of industrial and inorganic materials at other sites. Measured concentrations ranged from < 10 microg/m3 to approximately 40 microg/m3. Overall, PM10-2.5 concentrations measured with the passive samplers were within approximately 1 standard deviation of concentrations measured with the FRM samplers. Concentrations determined with passive samplers depend on assumptions about particle density and shape factors and may also depend somewhat on local wind speed and turbulence; accurate values for these parameters may not be known. The degree of agreement between passive and FRM concentrations measured here suggests that passive measurements may not be overly dependent on accurate knowledge of these parameters.

Passive sampling for the isotopic fingerprinting of atmospheric mercury

NASA Astrophysics Data System (ADS)

Bergquist, B. A.; MacLagan, D.; Spoznar, N.; Kaplan, R.; Chandan, P.; Stupple, G.; Zimmerman, L.; Wania, F.; Mitchell, C. P. J.; Steffen, A.; Monaci, F.; Derry, L. A.

2017-12-01

Recent studies show that there are variations in the mercury (Hg) isotopic signature of atmospheric Hg, which demonstrates the potential for source tracing and improved understanding of atmospheric cycling of Hg. However, current methods for both measuring atmospheric Hg and collecting enough atmospheric Hg for isotopic analyses require expensive instruments that need power and expertise. Additionally, methods for collecting enough atmospheric Hg for isotopic analysis require pumping air through traps for long periods (weeks and longer). Combining a new passive atmospheric sampler for mercury (Hg) with novel Hg isotopic analyses will allow for the application of stable Hg isotopes to atmospheric studies of Hg. Our group has been testing a new passive sampler for gaseous Hg that relies on the diffusion of Hg through a diffusive barrier and adsorption onto a sulphur-impregnated activated carbon sorbent. The benefit of this passive sampler is that it is low cost, requires no power, and collects gaseous Hg for up to one year with linear, well-defined uptake, which allows for reproducible and accurate measurements of atmospheric gaseous Hg concentrations ( 8% uncertainty). As little as one month of sampling is often adequate to collect sufficient Hg for isotopic analysis at typical background concentrations. Experiments comparing the isotopic Hg signature in activated carbon samples using different approaches (i.e. by passive diffusion, by passive diffusion through diffusive barriers of different thickness, by active pumping) and at different temperatures confirm that the sampling process itself does not impose mass-independent fractionation (MIF). However, sampling does result in a consistent and thus correctable mass-dependent fractionation (MDF) effect. Therefore, the sampler preserves Hg MIF with very high accuracy and precision, which is necessary for atmospheric source tracing, and reasonable MDF can be estimated with some increase in error. In addition to experimental work, initial field data will be presented including a transect of increasing distance from a known strong source of Hg (Mt. Amiata mine, Italy), downwind of Kilauea volcano in Hawaii, and several other locales including the Arctic station Alert and various sites across Ontario, Canada.

Biodigester Feasibility and Design for Space & Earth

NASA Technical Reports Server (NTRS)

Shutts, Stacy; Ewert, Mike; Bacon, Jack

2016-01-01

Anaerobic digestion converts organic waste into methane gas and fertilizer effluent. The ICA-developed prototype system is designed for planetary surface operation. It uses passive hydrostatic control for reliability, and is modular and redundant. The serpentine configuration accommodates tight geometric constraints similar to the ISS ECLSS rack architectures. Its shallow, low-tilt design enables (variable) lower-g convection than standard Earth (1 g) digesters. This technology will reuse and recycle materials including human waste, excess food, as well as packaging (if biodegradable bags are used).

Diffusion barriers

NASA Technical Reports Server (NTRS)

Nicolet, M. A.

1983-01-01

The choice of the metallic film for the contact to a semiconductor device is discussed. One way to try to stabilize a contact is by interposing a thin film of a material that has low diffusivity for the atoms in question. This thin film application is known as a diffusion barrier. Three types of barriers can be distinguished. The stuffed barrier derives its low atomic diffusivity to impurities that concentrate along the extended defects of a polycrystalline layer. Sacrificial barriers exploit the fact that some (elemental) thin films react in a laterally uniform and reproducible fashion. Sacrificial barriers have the advantage that the point of their failure is predictable. Passive barriers are those most closely approximating an ideal barrier. The most-studied case is that of sputtered TiN films. Stuffed barriers may be viewed as passive barriers whose low diffusivity material extends along the defects of the polycrystalline host.

Carrier-mediated cocaine transport at the blood-brain barrier as a putative mechanism in addiction liability.

PubMed

Chapy, Hélène; Smirnova, Maria; André, Pascal; Schlatter, Joël; Chiadmi, Fouad; Couraud, Pierre-Olivier; Scherrmann, Jean-Michel; Declèves, Xavier; Cisternino, Salvatore

2014-10-31

The rate of entry of cocaine into the brain is a critical factor that influences neuronal plasticity and the development of cocaine addiction. Until now, passive diffusion has been considered the unique mechanism known by which cocaine crosses the blood-brain barrier. We reassessed mechanisms of transport of cocaine at the blood-brain barrier using a human cerebral capillary endothelial cell line (hCMEC/D3) and in situ mouse carotid perfusion. Both in vivo and in vitro cocaine transport studies demonstrated the coexistence of a carrier-mediated process with passive diffusion. At pharmacological exposure level, passive diffusion of cocaine accounted for only 22.5% of the total cocaine influx in mice and 5.9% in hCMEC/D3 cells, whereas the carrier-mediated influx rate was 3.4 times greater than its passive diffusion rate in vivo. The functional identification of this carrier-mediated transport demonstrated the involvement of a proton antiporter that shared the properties of the previously characterized clonidine and nicotine transporter. The functionnal characterization suggests that the solute carrier (SLC) transporters Oct (Slc22a1-3), Mate (Slc47a1) and Octn (Slc22a4-5) are not involved in the cocaine transport in vivo and in vitro. Diphenhydramine, heroin, tramadol, cocaethylene, and norcocaine all strongly inhibited cocaine transport, unlike benzoylecgonine. Trans-stimulation studies indicated that diphenhydramine, nicotine, 3,4-methylenedioxyamphetamine (ecstasy) and the cathinone compound 3,4-methylenedioxypyrovalerone (MDPV) were also substrates of the cocaine transporter. Cocaine transport at the BBB involves a proton-antiporter flux that is quantitatively much more important than its passive diffusion. The molecular identification and characterization of this transporter will provide new tools to understand its role in addictive mechanisms. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Passive phloem loading and long-distance transport in a synthetic tree-on-a-chip.

PubMed

Comtet, Jean; Jensen, Kaare H; Turgeon, Robert; Stroock, Abraham D; Hosoi, A E

2017-03-20

Vascular plants rely on differences in osmotic pressure to export sugars from regions of synthesis (mature leaves) to sugar sinks (roots, fruits). In this process, known as Münch pressure flow, the loading of sugars from photosynthetic cells to the export conduit (the phloem) is crucial, as it sets the pressure head necessary to power long-distance transport. Whereas most herbaceous plants use active mechanisms to increase phloem sugar concentration above that of the photosynthetic cells, in most tree species, for which transport distances are largest, loading seems, counterintuitively, to occur by means of passive symplastic diffusion from the mesophyll to the phloem. Here, we use a synthetic microfluidic model of a passive loader to explore the non-linear dynamics that arise during export and determine the ability of passive loading to drive long-distance transport. We first demonstrate that in our device, the phloem concentration is set by the balance between the resistances to diffusive loading from the source and convective export through the phloem. Convection-limited export corresponds to classical models of Münch transport, where the phloem concentration is close to that of the source; in contrast, diffusion-limited export leads to small phloem concentrations and weak scaling of flow rates with hydraulic resistance. We then show that the effective regime of convection-limited export is predominant in plants with large transport resistances and low xylem pressures. Moreover, hydrostatic pressures developed in our synthetic passive loader can reach botanically relevant values as high as 10 bars. We conclude that passive loading is sufficient to drive long-distance transport in large plants, and that trees are well suited to take full advantage of passive phloem loading strategies.

A passive sampler for airborne formaldehyde

NASA Astrophysics Data System (ADS)

Grosjean, Daniel; Williams, Edwin L.

A simple, inexpensive passive sampler is described that is capable of reliable measurements of formaldehyde at the parts per billion (ppb) levels relevant to indoor and outdoor air quality. The passive sampler consists of a modified dual filter holder in which the upper stage serves as the diffusion barrier, the lower stage includes a 2,4-dinitrophenylhydrazine (DNPH)-coated filter which collects formaldehyde, and the space between the two stages serve as the diffusion gap. The measured sampling rate, 18.8 ± 1.8 ml min -1, was determined in experiments involving sampling of ppb levels of formaldehyde with the passive sampler and with DNPH-coated C 18 cartridges and agrees well with the value of 19.4 ± 2.0 ml min -1 calculated from theory. The measured sampling rate was independent of formaldehyde concentration (16-156 ppb) and sampling duration (1.5-72 h). The precision of the measurements for colocated passive samplers averaged 8.6% in purified and indoor air (office and museums) and 10.2% in photochemically polluted outdoor air. With a 1.2-μm pore size Teflon filter as the diffusion barrier, the detection limit is 32 ppb h, e.g. 4 ppb in an 8-h sample, 1.3 ppb in a 24-h sample, and so on. Perceived advantages and limitations of the sampler are discussed including flexibility, cost effectiveness and possible negative bias at high ambient levels of ozone.

Extraction of thermal Green's function using diffuse fields: a passive approach applied to thermography

NASA Astrophysics Data System (ADS)

Capriotti, Margherita; Sternini, Simone; Lanza di Scalea, Francesco; Mariani, Stefano

2016-04-01

In the field of non-destructive evaluation, defect detection and visualization can be performed exploiting different techniques relying either on an active or a passive approach. In the following paper the passive technique is investigated due to its numerous advantages and its application to thermography is explored. In previous works, it has been shown that it is possible to reconstruct the Green's function between any pair of points of a sensing grid by using noise originated from diffuse fields in acoustic environments. The extraction of the Green's function can be achieved by cross-correlating these random recorded waves. Averaging, filtering and length of the measured signals play an important role in this process. This concept is here applied in an NDE perspective utilizing thermal fluctuations present on structural materials. Temperature variations interacting with thermal properties of the specimen allow for the characterization of the material and its health condition. The exploitation of the thermographic image resolution as a dense grid of sensors constitutes the basic idea underlying passive thermography. Particular attention will be placed on the creation of a proper diffuse thermal field, studying the number, placement and excitation signal of heat sources. Results from numerical simulations will be presented to assess the capabilities and performances of the passive thermal technique devoted to defect detection and imaging of structural components.

Hydrodynamic effects on phase transition in active matter

NASA Astrophysics Data System (ADS)

Gidituri, Harinadha; Akella, V. S.; Panchagnula, Mahesh; Vedantam, Srikanth; Multiphase flow physics lab Team

2017-11-01

Organized motion of active (self-propelled) objects are ubiquitous in nature. The objective of this study to investigate the effect of hydrodynamics on the coherent structures in active and passive particle mixtures. We use a mesoscopic method Dissipative Particle Dynamics (DPD). The system shows three different states viz. meso-turbulent (disordered state), polar flock and vortical (ordered state) for different values of activity and volume fraction of active particles. From our numerical simulations we construct a phase diagram between activity co-efficient, volume fraction and viscosity of the passive fluid. Transition from vortical to polar is triggered by increasing the viscosity of passive fluid which causes strong short-range hydrodynamic interactions. However, as the viscosity of the fluid decreases, both vortical and meso-turbulent states transition to polar flock phase. We also calculated the diffusion co-efficients via mean square displacement (MSD) for passive and active particles. We observe ballistic and diffusive regimes in the present system.

Hydrodynamic collective effects of active protein machines in solution and lipid bilayers

PubMed Central

Mikhailov, Alexander S.; Kapral, Raymond

2015-01-01

The cytoplasm and biomembranes in biological cells contain large numbers of proteins that cyclically change their shapes. They are molecular machines that can function as molecular motors or carry out various other tasks in the cell. Many enzymes also undergo conformational changes within their turnover cycles. We analyze the advection effects that nonthermal fluctuating hydrodynamic flows induced by active proteins have on other passive molecules in solution or membranes. We show that the diffusion constants of passive particles are enhanced substantially. Furthermore, when gradients of active proteins are present, a chemotaxis-like drift of passive particles takes place. In lipid bilayers, the effects are strongly nonlocal, so that active inclusions in the entire membrane contribute to local diffusion enhancement and the drift. All active proteins in a biological cell or in a membrane contribute to such effects and all passive particles, and the proteins themselves, will be subject to them. PMID:26124140

Numerical investigation of metal-semiconductor-insulator-semiconductor passivated hole contacts based on atomic layer deposited AlO x

NASA Astrophysics Data System (ADS)

Ke, Cangming; Xin, Zheng; Ling, Zhi Peng; Aberle, Armin G.; Stangl, Rolf

2017-08-01

Excellent c-Si tunnel layer surface passivation has been obtained recently in our lab, using atomic layer deposited aluminium oxide (ALD AlO x ) in the tunnel layer regime of 0.9 to 1.5 nm, investigated to be applied for contact passivation. Using the correspondingly measured interface properties, this paper compares the theoretical collection efficiency of a conventional metal-semiconductor (MS) contact on diffused p+ Si to a metal-semiconductor-insulator-semiconductor (MSIS) contact on diffused p+ Si or on undoped n-type c-Si. The influences of (1) the tunnel layer passivation quality at the tunnel oxide interface (Q f and D it), (2) the tunnel layer thickness and the electron and hole tunnelling mass, (3) the tunnel oxide material, and (4) the semiconductor capping layer material properties are investigated numerically by evaluation of solar cell efficiency, open-circuit voltage, and fill factor.

Use of Passive Diffusion Samplers for Monitoring Volatile Organic Compounds in Ground Water

USGS Publications Warehouse

Harte, Philip T.; Brayton, Michael J.; Ives, Wayne

2000-01-01

Passive diffusion samplers have been tested at a number of sites where volatile organic compounds (VOC's) are the principal contaminants in ground water. Test results generally show good agreement between concentrations of VOC's in samples collected with diffusion samplers and concentrations in samples collected by purging the water from a well. Diffusion samplers offer several advantages over conventional and low-flow ground-water sampling procedures: * Elimination of the need to purge a well before collecting a sample and to dispose of contaminated water. * Elimination of cross-contamination of samples associated with sampling with non-dedicated pumps or sample delivery tubes. * Reduction in sampling time by as much as 80 percent of that required for 'purge type' sampling methods. * An increase in the frequency and spatial coverage of monitoring at a site because of the associated savings in time and money. The successful use of diffusion samplers depends on the following three primary factors: (1) understanding site conditions and contaminants of interest (defining sample objectives), (2) validating of results of diffusion samplers against more widely acknowledged sampling methods, and (3) applying diffusion samplers in the field.

Random walk of passive tracers among randomly moving obstacles.

PubMed

Gori, Matteo; Donato, Irene; Floriani, Elena; Nardecchia, Ilaria; Pettini, Marco

2016-04-14

This study is mainly motivated by the need of understanding how the diffusion behavior of a biomolecule (or even of a larger object) is affected by other moving macromolecules, organelles, and so on, inside a living cell, whence the possibility of understanding whether or not a randomly walking biomolecule is also subject to a long-range force field driving it to its target. By means of the Continuous Time Random Walk (CTRW) technique the topic of random walk in random environment is here considered in the case of a passively diffusing particle among randomly moving and interacting obstacles. The relevant physical quantity which is worked out is the diffusion coefficient of the passive tracer which is computed as a function of the average inter-obstacles distance. The results reported here suggest that if a biomolecule, let us call it a test molecule, moves towards its target in the presence of other independently interacting molecules, its motion can be considerably slowed down.

Use of Inert Gases to Study the Interaction of Blood Flow and Diffusion during Passive Absorption from the Gastrointestinal Tract of the Rat

PubMed Central

Levitt, Michael D.; Levitt, David G.

1973-01-01

Measurement of the relative absorption rates of inert gases (H2, He, CH4, SF6, and 133Xe) was used to investigate the interaction between diffusion and blood flow during passive absorption from the stomach, small bowel, and colon of the rat. If uptake is blood flow limited, the gases should be absorbed in proportion to their solubilities in blood, but if diffusion limited, uptake should be proportional to the diffusion rate of the gases in mucosal tissues. The observed absorption data were fitted to a series of models of interaction between perfusion and diffusion. A simple model accurately predicted the absorption rates of the gases from all segments of bowel. In this model, gas is absorbed into two distinct blood flows: one which flows in proximity to the lumen and completely equilibrates with the lumen, and a second which is sufficiently rapid and distant from the lumen that its gas uptake is entirely diffusion limited. The fraction of the total absorption attributable to the equilibrating flow can be readily calculated and equalled 93%, 77%, and 33% for the small bowel, colon, and stomach, respectively. Thus the rate of passive absorption of gases from the small bowel is limited almost entirely by the blood flow to the mucosa, and absorption from the stomach is largely limited by the diffusion rate of the gases. The flow which equilibrates with the lumen can be quantitated, and this flow may provide a useful measure of “effective” mucosal blood flow. Images PMID:4719667

Assessment of passive muscle elongation using Diffusion Tensor MRI: Correlation between fiber length and diffusion coefficients.

PubMed

Mazzoli, Valentina; Oudeman, Jos; Nicolay, Klaas; Maas, Mario; Verdonschot, Nico; Sprengers, Andre M; Nederveen, Aart J; Froeling, Martijn; Strijkers, Gustav J

2016-12-01

In this study we investigated the changes in fiber length and diffusion parameters as a consequence of passive lengthening and stretching of the calf muscles. We hypothesized that changes in radial diffusivity (RD) are caused by changes in the muscle fiber cross sectional area (CSA) as a consequence of lengthening and shortening of the muscle. Diffusion Tensor MRI (DT-MRI) measurements were made twice in five healthy volunteers, with the foot in three different positions (30° plantarflexion, neutral position and 15° dorsiflexion). The muscles of the calf were manually segmented on co-registered high resolution anatomical scans, and maps of RD and axial diffusivity (AD) were reconstructed from the DT-MRI data. Fiber tractography was performed and mean fiber length was calculated for each muscle group. Significant negative correlations were found between the changes in RD and changes in fiber length in the dorsiflexed and plantarflexed positions, compared with the neutral foot position. Changes in AD did not correlate with changes in fiber length. Assuming a simple cylindrical model with constant volume for the muscle fiber, the changes in the muscle fiber CSA were calculated from the changes in fiber length. In line with our hypothesis, we observed a significant positive correlation of the CSA with the measured changes in RD. In conclusion, we showed that changes in diffusion coefficients induced by passive muscle stretching and lengthening can be explained by changes in muscle CSA, advancing the physiological interpretation of parameters derived from skeletal muscle DT-MRI. Copyright © 2016 John Wiley & Sons, Ltd.

Passivation of phosphorus diffused silicon surfaces with Al{sub 2}O{sub 3}: Influence of surface doping concentration and thermal activation treatments

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

Richter, Armin, E-mail: armin.richter@ise.fraunhofer.de; Benick, Jan; Kimmerle, Achim

2014-12-28

Thin layers of Al{sub 2}O{sub 3} are well known for the excellent passivation of p-type c-Si surfaces including highly doped p{sup +} emitters, due to a high density of fixed negative charges. Recent results indicate that Al{sub 2}O{sub 3} can also provide a good passivation of certain phosphorus-diffused n{sup +} c-Si surfaces. In this work, we studied the recombination at Al{sub 2}O{sub 3} passivated n{sup +} surfaces theoretically with device simulations and experimentally for Al{sub 2}O{sub 3} deposited with atomic layer deposition. The simulation results indicate that there is a certain surface doping concentration, where the recombination is maximal duemore » to depletion or weak inversion of the charge carriers at the c-Si/Al{sub 2}O{sub 3} interface. This pronounced maximum was also observed experimentally for n{sup +} surfaces passivated either with Al{sub 2}O{sub 3} single layers or stacks of Al{sub 2}O{sub 3} capped by SiN{sub x}, when activated with a low temperature anneal (425 °C). In contrast, for Al{sub 2}O{sub 3}/SiN{sub x} stacks activated with a short high-temperature firing process (800 °C) a significant lower surface recombination was observed for most n{sup +} diffusion profiles without such a pronounced maximum. Based on experimentally determined interface properties and simulation results, we attribute this superior passivation quality after firing to a better chemical surface passivation, quantified by a lower interface defect density, in combination with a lower density of negative fixed charges. These experimental results reveal that Al{sub 2}O{sub 3}/SiN{sub x} stacks can provide not only excellent passivation on p{sup +} surfaces but also on n{sup +} surfaces for a wide range of surface doping concentrations when activated with short high-temperature treatments.« less

The Role of Surface Passivation in Controlling Ge Nanowire Faceting.

PubMed

Gamalski, A D; Tersoff, J; Kodambaka, S; Zakharov, D N; Ross, F M; Stach, E A

2015-12-09

In situ transmission electron microscopy observations of nanowire morphologies indicate that during Au-catalyzed Ge nanowire growth, Ge facets can rapidly form along the nanowire sidewalls when the source gas (here, digermane) flux is decreased or the temperature is increased. This sidewall faceting is accompanied by continuous catalyst loss as Au diffuses from the droplet to the wire surface. We suggest that high digermane flux and low temperatures promote effective surface passivation of Ge nanowires with H or other digermane fragments inhibiting diffusion and attachment of Au and Ge on the sidewalls. These results illustrate the essential roles of the precursor gas and substrate temperature in maintaining nanowire sidewall passivation, necessary to ensure the growth of straight, untapered, ⟨111⟩-oriented nanowires.

Influence of surfactant on the drop bag breakup in a continuous air jet stream

NASA Astrophysics Data System (ADS)

Zhao, Hui; Zhang, Wen-Bin; Xu, Jian-Liang; Li, Wei-Feng; Liu, Hai-Feng

2016-05-01

The deformation and breakup of surfactant-laden drops is a common phenomenon in nature and numerous practical applications. We investigate influence of surfactant on the drop bag breakup in a continuous air jet stream. The airflow would induce the advection diffusion of surfactant between interface and bulk of drop. Experiments indicate that the convective motions of deforming drop would induce the non-equilibrium distribution of surfactant, which leads to the change of surface tension. When the surfactant concentration is smaller than critical micelle concentration (CMC), with the increase of surface area of drop, the surface tension of liquid-air interface and the critical Weber number will increase. When the surfactant concentration is bigger than CMC, the micelle can be considered as the source term, which can supply the monomers. So in the presence of surfactant, there would be the significant nonlinear variation on the critical Weber number of bag breakup. We build the dynamic non-monotonic relationship between concentrations of surfactant and critical Weber number theoretically. In the range of parameters studied, the experimental results are consistent with the model estimates.

Response to a small external force and fluctuations of a passive particle in a one-dimensional diffusive environment

NASA Astrophysics Data System (ADS)

Huveneers, François

2018-04-01

We investigate the long-time behavior of a passive particle evolving in a one-dimensional diffusive random environment, with diffusion constant D . We consider two cases: (a) The particle is pulled forward by a small external constant force and (b) there is no systematic bias. Theoretical arguments and numerical simulations provide evidence that the particle is eventually trapped by the environment. This is diagnosed in two ways: The asymptotic speed of the particle scales quadratically with the external force as it goes to zero, and the fluctuations scale diffusively in the unbiased environment, up to possible logarithmic corrections in both cases. Moreover, in the large D limit (homogenized regime), we find an important transient region giving rise to other, finite-size scalings, and we describe the crossover to the true asymptotic behavior.

Development of a passive sampler for gaseous mercury

NASA Astrophysics Data System (ADS)

Gustin, M. S.; Lyman, S. N.; Kilner, P.; Prestbo, E.

2011-10-01

Here we describe work toward development of the components of a cost effective passive sampling system for gaseous Hg that could be broadly deployed by nontechnical staff. The passive sampling system included an external shield to reduce turbulence and exposure to precipitation and dust, a diffusive housing that directly protects the collection surface during deployment and handling, and a collection surface. A protocol for cleaning and deploying the sampler and an analytical method were developed. Our final design consisted of a polycarbonate external shield enclosing a custom diffusive housing made from expanded PTFE tubing. Two collection surfaces were investigated, gold sputter-coated quartz plates and silver wires. Research showed the former would require extensive quality control for use, while the latter had interferences with other atmosphere constituents. Although the gold surface exhibited the best performance over space and time, gradual passivation would limit reuse. For both surfaces lack of contamination during shipping, deployment and storage indicated that the handling protocols developed worked well with nontechnical staff. We suggest that the basis for this passive sampling system is sound, but further exploration and development of a reliable collection surface is needed.

Quantitative characterization of brazing performance for Sn-plated silver alloy fillers

NASA Astrophysics Data System (ADS)

Wang, Xingxing; Peng, Jin; Cui, Datian

2017-12-01

Two types of AgCuZnSn fillers were prepared based on BAg50CuZn and BAg34CuZnSn alloy through a combinative process of electroplating and thermal diffusion. The models of wetting entropy and joint strength entropy of AgCuZnSn filler metals were established. The wetting entropy of the Sn-plated silver brazing alloys are lower than the traditional fillers, and its joint strength entropy value is slightly higher than the latter. The wetting entropy value of the Sn-plated brazing alloys and traditional filler metal are similar to the change trend of the wetting area. The trend of the joint strength entropy value with those fillers are consisted with the tensile strength of the stainless steel joints with the increase of Sn content.

Role of Passive Diffusion, Transporters, and Membrane Trafficking-Mediated Processes in Cellular Drug Transport.

PubMed

Cocucci, E; Kim, J Y; Bai, Y; Pabla, N

2017-01-01

Intracellular drug accumulation is thought to be dictated by two major processes, passive diffusion through the lipid membrane or membrane transporters. The relative role played by these distinct processes remains actively debated. Moreover, the role of membrane-trafficking in drug transport remains underappreciated and unexplored. Here we discuss the distinct processes involved in cellular drug distribution and propose that better experimental models are required to elucidate the differential contributions of various processes in intracellular drug accumulation. © 2016 American Society for Clinical Pharmacology and Therapeutics.

Relative contributions of active mediated transport and passive diffusion of fluoroquinolones with various lipophilicities in a Calu-3 lung epithelial cell model.

PubMed

Brillault, Julien; De Castro, Whocely Victor; Couet, William

2010-01-01

The transport characteristics of six fluoroquinolones (FQs) with various lipophilicities were compared in a Calu-3 cell model. For each FQ, an active polarized transport was observed in the direction of the apical side. However, the apparent permeability of FQs resulted from active transport and passive diffusion that were highly variable between compounds and mainly governed by lipophilicity. Therefore, active transport was predominant for compounds with relatively low lipophilicity but minor for FQs with higher lipophilicity.

Synthesis, characterization and field evaluation of a new calcium-based CO2 absorbent for radial diffusive sampler

NASA Astrophysics Data System (ADS)

Cucciniello, Raffaele; Proto, Antonio; Alfano, Davide; Motta, Oriana

2012-12-01

In this paper the use of passive sampling as a powerful approach to monitor atmospheric CO2 is assessed. Suitable substrate based on calcium-aluminium oxide was synthetized according to a process which permits to control the particle size of the CaO/Al based sorbent. The study shows that hydration of substrate is an essential part of the process of CO2 absorption and subsequent conversion to carbonate. X-ray diffraction, thermogravimetric analysis, environmental scanning electron microscopic analysis were used in order to characterize the substrate and to establish the best performances both in terms of particle size and CO2 absorption capacity. Passive samplers for CO2 monitoring were prepared and then tested at laboratory level and in the atmospheric environment. Validation was performed by comparison with an infrared continuous detector. Thermogravimetric analysis results, carried out to evaluate the absorbing capability of this new passive device, were in accordance with data collected at the same time by the active continuous analyser. The diffusive sampling rate and the diffusion coefficient of CO2 respect to this new passive device were also evaluated resulting equal to 47 ± 3 ml min-1 and 0.0509 ± 0.005 cm2 s-1, respectively.

Diffusive mixing through velocity profile variation in microchannels

NASA Astrophysics Data System (ADS)

Yakhshi-Tafti, Ehsan; Cho, Hyoung J.; Kumar, Ranganathan

2011-03-01

Rapid mixing does not readily occur at low Reynolds number flows encountered in microdevices; however, it can be enhanced by passive diffusive mixing schemes. This study of micromixing of two miscible fluids is based on the principle that (1) increased velocity at the interface of co-flowing fluids results in increased diffusive mass flux across their interface, and (2) diffusion interfaces between two liquids progress transversely as the flow proceeds downstream. A passive micromixer is proposed that takes advantage of the peak velocity variation, inducing diffusive mixing. The effect of flow variation on the enhancement of diffusive mixing is investigated analytically and experimentally. Variation of the flow profile is confirmed using micro-Particle Image Velocimetry (μPIV) and mixing is evaluated by color variations resulting from the mixing of pH indicator and basic solutions. Velocity profile variations obtained from μPIV show a shift in peak velocities. The mixing efficiency of the Σ-micromixer is expected to be higher than that for a T-junction channel and can be as high as 80%. The mixing efficiency decreases with Reynolds number and increases with downstream length, exhibiting a power law.

The role of surface passivation in controlling Ge nanowire faceting

DOE PAGES

Gamalski, A. D.; Tersoff, J.; Kodambaka, S.; ...

2015-11-05

In situ transmission electron microscopy observations of nanowire morphologies indicate that during Au-catalyzed Ge nanowire growth, Ge facets can rapidly form along the nanowire sidewalls when the source gas (here, digermane) flux is decreased or the temperature is increased. This sidewall faceting is accompanied by continuous catalyst loss as Au diffuses from the droplet to the wire surface. We suggest that high digermane flux and low temperatures promote effective surface passivation of Ge nanowires with H or other digermane fragments inhibiting diffusion and attachment of Au and Ge on the sidewalls. Furthermore, these results illustrate the essential roles of themore » precursor gas and substrate temperature in maintaining nanowire sidewall passivation, necessary to ensure the growth of straight, untapered, <111>-oriented nanowires.« less

A field evaluation of a SO 2 passive sampler in tropical industrial and urban air

NASA Astrophysics Data System (ADS)

Cruz, Lícia P. S.; Campos, Vânia P.; Silva, Adriana M. C.; Tavares, Tania M.

Passive samplers have been widely used for over 30 years in the measurement of personal exposure to vapours and gases in the workplace. These samplers have just recently been applied in the monitoring of ambient air, which presents concentrations that are normally much smaller than those found in occupational environments. The locally constructed passive sampler was based on gas molecular diffusion through static air layer. The design used minimizes particle interference and turbulent diffusion. After exposure, the SO 2 trapped in impregnated filters with Na 2CO 3 was extracted by means of an ultrasonic bath, for 15 min, using 1.0×10 -2 mol L -1 H 2O 2. It was determined as SO 4-2 by ion chromatography. The performance of the passive sampler was evaluated at different exposure periods, being applied in industrial and urban areas. Method precision as relative standard deviation for three simultaneously applied passive samplers was within 10%. Passive sampling, when compared to active monitoring methods under real conditions, used in urban and industrial areas, showed an overall accuracy of 15%. A statistical comparison with an active method was performed to demonstrate the validity of the passive method. Sampler capacity varied between 98 and 421 μg SO 2 m -3 for exposure periods of one month and one week, respectively, which allows its use in highly polluted areas.

Low cost fuel cell diffusion layer configured for optimized anode water management

DOEpatents

Owejan, Jon P; Nicotera, Paul D; Mench, Matthew M; Evans, Robert E

2013-08-27

A fuel cell comprises a cathode gas diffusion layer, a cathode catalyst layer, an anode gas diffusion layer, an anode catalyst layer and an electrolyte. The diffusion resistance of the anode gas diffusion layer when operated with anode fuel is higher than the diffusion resistance of the cathode gas diffusion layer. The anode gas diffusion layer may comprise filler particles having in-plane platelet geometries and be made of lower cost materials and manufacturing processes than currently available commercial carbon fiber substrates. The diffusion resistance difference between the anode gas diffusion layer and the cathode gas diffusion layer may allow for passive water balance control.

Performance of a passive direct ethanol fuel cell

NASA Astrophysics Data System (ADS)

Pereira, J. P.; Falcão, D. S.; Oliveira, V. B.; Pinto, A. M. F. R.

2014-06-01

Ethanol emerges as an attractive fuel since it is less toxic and has higher energy density than methanol and can be produced from biomass. Direct ethanol fuel cells (DEFCs) appear as a good choice for producing sustainable energy for portable applications. However, they are still far from attaining acceptable levels of power output, since their performance is affected by the slow electrochemical ethanol oxidation and water and ethanol crossover. In the present work, an experimental study on the performance of a passive DEFC is described. Tailored MEAs (membrane electrode assembly) with different catalyst loadings, anode diffusion layers and membranes were tested in order to select optimal working conditions at high ethanol concentrations and low ethanol crossover. The performance increased with an increase of membrane and anode diffusion layer thicknesses and anode catalyst loading. A maximum power density of 1.33 mW cm-2, was obtained using a Nafion 117 membrane, 4 mg cm-2 of Pt-Ru and 2 mg cm-2 of Pt on the anode and cathode catalyst layers, ELAT as anode diffusion layer, carbon cloth as cathode diffusion layer and an ethanol concentration of 2 M. As far as the authors are aware this is the first work reporting an experimental optimization of passive DEFCs.

Facility fence-line monitoring using passive samplers

EPA Science Inventory

In 2009, the U.S. EPA executed a year-long field study at a refinery in Corpus Christi, Texas, to evaluate the use of passive diffusive sampling technology for assessing time-averaged benzene concentrations at the facility fence line. The study utilized 14-day time-integrated Car...

Modeling and Simulation of Lab-on-a-Chip Systems

DTIC Science & Technology

2005-08-12

complex chip geometries (including multiple turns). Variations of sample concentration profiles in laminar diffusion-based micromixers are also derived...CHAPTER 6 MODELING OF LAMINAR DIFFUSION-BASED COMPLEX ELECTROKINETIC PASSIVE MICROMIXERS ...140 6.4.4 Multi-Stream (Inter-Digital) Micromixers

Perioperative thermal insulation.

PubMed

Sessler, D I; McGuire, J; Sessler, A M

1991-05-01

To determine the efficacy of passive insulators advocated for prevention of cutaneous heat loss, we determined heat loss in unanesthetized volunteers covered by one of the following: a cloth "split sheet" surgical drape; a Convertors disposable-paper split sheet; a Thermadrape disposable laparotomy sheet; an unheated Bair Hugger patient-warming blanket; 1.5-mil-thick plastic hamper bags; and a prewarmed, cotton hospital blanket. Cutaneous heat loss was measured using 10 area-weighted thermal flux transducers while volunteers were exposed to a 20.6 degrees C environment for 1 h. Heat loss decreased significantly from 100 +/- 3 W during the control periods to 69 +/- 6 W (average of all covers) after 1 h of treatment. Heat losses from volunteers insulated by the Thermadrape (61 +/- 6 W) and Bair Hugger covers (64 +/- 5 W) were significantly less than losses from those insulated by plastic bags (77 +/- 11 W). The paper drape (67 +/- 7 W) provided slightly, but not significantly, better insulation than the cloth drape (70 +/- 4 W). Coverage by prewarmed cotton blankets initially resulted in the least heat loss (58 +/- 8 W), but after 40 min, resulted in heat loss significantly greater than that for the Thermadrape (71 +/- 7 W). Regional heat loss was roughly proportional to surface area, and the distribution of regional heat loss remained similar with all covers. These data suggest that cost and convenience should be major factors when choosing among passive perioperative insulating covers. It is likely that the amount of skin surface covered is more important than the choice of skin region covered or the choice of insulating material.

Understanding of Relationship between Phospholipid Membrane Permeability and Self-Diffusion Coefficients of Some Drugs and Biologically Active Compounds in Model Solvents.

PubMed

Blokhina, Svetlana V; Volkova, Tatyana V; Golubev, Vasiliy A; Perlovich, German L

2017-10-02

In this work we measured self-diffusion coefficients of 5 drugs (aspirin, caffeine, ethionamide, salicylic acid, and paracetamol) and 11 biologically active compounds of similar structure in deuterated water and 1-octanol by NMR. It has been found that an increase in the van der Waals volume of the molecules of the studied substances result in reduction of their diffusion mobility in both solvents. The analysis of the experimental data showed the influence of chemical nature and structural isomerization of the molecules on the diffusion mobility. Apparent permeability coefficients of the studied compounds were determined using an artificial phospholipid membrane made of egg lecithin as a model of in vivo absorption. Distribution coefficients in 1-octanol/buffer pH 7.4 system were measured. For the first time the model of the passive diffusion through the phospholipid membrane was validated based on the experimental data. To this end, the passive diffusion was considered as an additive process of molecule passage through the aqueous boundary layer before the membrane and 1-octanol barrier simulating the lipid layer of the membrane.

Scaling behavior in corrosion and growth of a passive film.

PubMed

Aarão Reis, F D A; Stafiej, Janusz

2007-07-01

We study a simple model for metal corrosion controlled by the reaction rate of the metal with an anionic species and the diffusion of that species in the growing passive film between the solution and the metal. A crossover from the reaction-controlled to the diffusion-controlled growth regime with different roughening properties is observed. Scaling arguments provide estimates of the crossover time and film thickness as functions of the reaction and diffusion rates and the concentration of anionic species in the film-solution interface, including a nontrivial square-root dependence on that concentration. At short times, the metal-film interface exhibits Kardar-Parisi-Zhang (KPZ) scaling, which crosses over to a diffusion-limited erosion (Laplacian growth) regime at long times. The roughness of the metal-film interface at long times is obtained as a function of the rates of reaction and diffusion and of the KPZ growth exponent. The predictions have been confirmed by simulations of a lattice version of the model in two dimensions. Relations with other erosion and corrosion models and possible applications are discussed.

Effect of ultrasonic cavitation on the diffusivity of a point defect in the passive film on formed Nb in 0.5 M HCl solution.

PubMed

Li, D G

2015-11-01

This work primarily focused on the influence of ultrasonic cavitation on the transport property of the point defect in the passive film on formed Nb in 0.5M HCl solution via electrochemical techniques based on the point defect model (PDM). The influence of ultrasonic cavitation on the composition and structure of the passive film was detected by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). The transport property of a point defect in the passive film was characterized by the diffusivity of the point defect (D0). The influences of the ultrasonic cavitation power, passivated time and the distance between horn bottom and sample surface on D0 were analyzed. The results demonstrated that the passive film formed on Nb was an n-type semiconductor with a donor density (ND) ranging from 10(19) cm(-3) to 10(20) cm(-3) in the case of static state, while the order of ND increased one to two times by applying ultrasonic cavitation during film formation. The diffusivity of the point defect (D0) in the passive film formed on Nb at 0.5 V for 1 h in a 0.5 M HCl solution in the static state was calculated to be 9.704×10(-18) cm(2) s(-1), and it increased to 1.255×10(-16) cm(2) s(-1), 7.259×10(-16) cm(2) s(-1) and 7.296×10(-15) cm(2) s(-1) when applying the 180 W, 270 W and 450 W ultrasonic cavitation powers during film formation. D0 increased with the increment of the ultrasonic cavitation power, and decreased with the increased in formation time and distance between the horn bottom and sample surface. AES results showed the film structure and composition were changed by applying the ultrasonic cavitation. XPS results revealed that the passive film was mainly composed of Nb2O5 in the static state, and the low valence Nb-oxide (NbO) appeared in the passive film except Nb2O5 in the case of applying a 270 W ultrasonic cavitation power. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluation of the availability of bound analyte for passive sampling in the presence of mobile binding matrix.

PubMed

Xu, Jianqiao; Huang, Shuyao; Jiang, Ruifen; Cui, Shufen; Luan, Tiangang; Chen, Guosheng; Qiu, Junlang; Cao, Chenyang; Zhu, Fang; Ouyang, Gangfeng

2016-04-21

Elucidating the availability of the bound analytes for the mass transfer through the diffusion boundary layers (DBLs) adjacent to passive samplers is important for understanding the passive sampling kinetics in complex samples, in which the lability factor of the bound analyte in the DBL is an important parameter. In this study, the mathematical expression of lability factor was deduced by assuming a pseudo-steady state during passive sampling, and the equation indicated that the lability factor was equal to the ratio of normalized concentration gradients between the bound and free analytes. Through the introduction of the mathematical expression of lability factor, the modified effective average diffusion coefficient was proven to be more suitable for describing the passive sampling kinetics in the presence of mobile binding matrixes. Thereafter, the lability factors of the bound polycyclic aromatic hydrocarbons (PAHs) with sodium dodecylsulphate (SDS) micelles as the binding matrixes were figured out according to the improved theory. The lability factors were observed to decrease with larger binding ratios and smaller micelle sizes, and were successfully used to predict the mass transfer efficiencies of PAHs through DBLs. This study would promote the understanding of the availability of bound analytes for passive sampling based on the theoretical improvements and experimental assessments. Copyright © 2016 Elsevier B.V. All rights reserved.

Numerical study of air ingress transition to natural circulation in a high temperature helium loop

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

Franken, Daniel; Gould, Daniel; Jain, Prashant K.

Here, the generation-IV high temperature gas cooled reactors (HTGRs) are designed with many passive safety features, one of which is the ability to passively remove heat under a loss of coolant accident (LOCA). However, several common reactor designs do not prevent against a large break in the coolant system and may therefore experience a depressurized LOCA. This would lead to air entering into the reactor system via several potential modes of ingress: diffusion, gravity currents, and natural circulation. At the onset of a LOCA, the initial rate of air ingress is expected to be very slow because it is governedmore » by molecular diffusion. However, after several hours, natural circulation would commence, thus, bringing the air into the reactor system at a much higher rate. As a consequence, air ingress would cause the high temperature graphite matrix to oxidize, leading to its thermal degradation and decreased passive heat (decay) removal capability. Therefore, it is essential to understand the transition of air ingress from molecular diffusion to natural circulation in an HTGR system. This paper presents results from a computational fluid dynamics (CFD) model to study the air ingress transition behavior. These results are validated against an h-shaped high temperature helium loop experiment. Details are provided to quantitatively predict the transition time from molecular diffusion to natural circulation.« less

Numerical study of air ingress transition to natural circulation in a high temperature helium loop

DOE PAGES

Franken, Daniel; Gould, Daniel; Jain, Prashant K.; ...

2017-09-21

Here, the generation-IV high temperature gas cooled reactors (HTGRs) are designed with many passive safety features, one of which is the ability to passively remove heat under a loss of coolant accident (LOCA). However, several common reactor designs do not prevent against a large break in the coolant system and may therefore experience a depressurized LOCA. This would lead to air entering into the reactor system via several potential modes of ingress: diffusion, gravity currents, and natural circulation. At the onset of a LOCA, the initial rate of air ingress is expected to be very slow because it is governedmore » by molecular diffusion. However, after several hours, natural circulation would commence, thus, bringing the air into the reactor system at a much higher rate. As a consequence, air ingress would cause the high temperature graphite matrix to oxidize, leading to its thermal degradation and decreased passive heat (decay) removal capability. Therefore, it is essential to understand the transition of air ingress from molecular diffusion to natural circulation in an HTGR system. This paper presents results from a computational fluid dynamics (CFD) model to study the air ingress transition behavior. These results are validated against an h-shaped high temperature helium loop experiment. Details are provided to quantitatively predict the transition time from molecular diffusion to natural circulation.« less

A MULTI-STREAM MODEL FOR VERTICAL MIXING OF A PASSIVE TRACER IN THE CONVECTIVE BOUNDARY LAYER

EPA Science Inventory

We study a multi-stream model (MSM) for vertical mixing of a passive tracer in the convective boundary layer, in which the tracer is advected by many vertical streams with different probabilities and diffused by small scale turbulence. We test the MSM algorithm for investigatin...

Pesticide impact on aquatic invertebrates identified with Chemcatcher® passive samplers and the SPEAR(pesticides) index.

PubMed

Münze, Ronald; Orlinskiy, Polina; Gunold, Roman; Paschke, Albrecht; Kaske, Oliver; Beketov, Mikhail A; Hundt, Matthias; Bauer, Coretta; Schüürmann, Gerrit; Möder, Monika; Liess, Matthias

2015-12-15

Pesticides negatively affect biodiversity and ecosystem function in aquatic environments. In the present study, we investigated the effects of pesticides on stream macroinvertebrates at 19 sites in a rural area dominated by forest cover and arable land in Central Germany. Pesticide exposure was quantified with Chemcatcher® passive samplers equipped with a diffusion-limiting membrane. Ecological effects on macroinvertebrate communities and on the ecosystem function detritus breakdown were identified using the indicator system SPEARpesticides and the leaf litter degradation rates, respectively. A decrease in the abundance of pesticide-vulnerable taxa and a reduction in leaf litter decomposition rates were observed at sites contaminated with the banned insecticide Carbofuran (Toxic Units≥-2.8), confirming the effect thresholds from previous studies. The results show that Chemcatcher® passive samplers with a diffusion-limiting membrane reliably detect ecologically relevant pesticide pollution, and we suggest Chemcatcher® passive samplers and SPEARpesticides as a promising combination to assess pesticide exposure and effects in rivers and streams. Copyright © 2015 Elsevier B.V. All rights reserved.

Combining Passive Microwave and Optical Data to Estimate Snow Water Equivalent in Afghanistan's Hindu Kush

NASA Astrophysics Data System (ADS)

Dozier, J.; Bair, N.; Calfa, A. A.; Skalka, C.; Tolle, K.; Bongard, J.

2015-12-01

The task is to estimate spatiotemporally distributed estimates of snow water equivalent (SWE) in snow-dominated mountain environments, including those that lack on-the-ground measurements such as the Hindu Kush range in Afghanistan. During the snow season, we can use two measurements: (1) passive microwave estimates of SWE, which generally underestimate in the mountains; (2) fractional snow-covered area from MODIS. Once the snow has melted, we can reconstruct the accumulated SWE back to the last significant snowfall by calculating the energy used in melt. The reconstructed SWE values provide a training set for predictions from the passive microwave SWE and snow-covered area. We examine several machine learning methods—regression-boosted decision trees, bagged trees, neural networks, and genetic programming—to estimate SWE. All methods work reasonably well, with R2 values greater than 0.8. Predictors built with multiple years of data reduce the bias that usually appears if we predict one year from just one other year's training set. Genetic programming tends to produce results that additionally provide physical insight. Adding precipitation estimates from the Global Precipitation Measurements mission is in progress.

Calculating the diffusive flux of persistent organic pollutants between sediments and the water column on the Palos Verdes shelf superfund site using polymeric passive samplers.

PubMed

Fernandez, Loretta A; Lao, Wenjian; Maruya, Keith A; Burgess, Robert M

2014-04-01

Passive samplers were deployed to the seafloor at a marine Superfund site on the Palos Verdes Shelf, California, USA, and used to determine water concentrations of persistent organic pollutants (POPs) in the surface sediments and near-bottom water. A model of Fickian diffusion across a thin water boundary layer at the sediment-water interface was used to calculate flux of contaminants due to molecular diffusion. Concentrations at four stations were used to calculate the flux of DDE, DDD, DDMU, and selected PCB congeners from sediments to the water column. Three passive sampling materials were compared: PE strips, POM strips, and SPME fibers. Performance reference compounds (PRCs) were used with PE and POM to correct for incomplete equilibration, and the resulting POP concentrations, determined by each material, agreed within 1 order of magnitude. SPME fibers, without PRC corrections, produced values that were generally much lower (1 to 2 orders of magnitude) than those measured using PE and POM, indicating that SPME may not have been fully equilibrated with waters being sampled. In addition, diffusive fluxes measured using PE strips at stations outside of a pilot remedial sand cap area were similar to those measured at a station inside the capped area: 240 to 260 ng cm(-2) y(-1) for p,p'-DDE. The largest diffusive fluxes of POPs were calculated at station 8C, the site where the highest sediment concentrations have been measured in the past, 1100 ng cm(-2) y(-1) for p,p'-DDE.

Optical tracer size differences allow quantitation of active pumping rate versus Stokes-Einstein diffusion in lymphatic transport

NASA Astrophysics Data System (ADS)

DSouza, Alisha V.; Marra, Kayla; Gunn, Jason R.; Samkoe, Kimberley S.; Pogue, Brian W.

2016-10-01

Lymphatic uptake of interstitially administered agents occurs by passive convective-diffusive inflow driven by interstitial concentration and pressure, while the downstream lymphatic transport is facilitated by active propulsive contractions of lymphatic vessel walls. Near-infrared fluorescence imaging in mice was used to measure these central components of lymphatic transport for the first time, using two different-sized molecules-methylene blue (MB) and fluorescence-labeled antibody immunoglobulin G (IgG)-IRDye 680RD. This work confirms the hypothesis that lymphatic passive inflow and active propulsion rates can be separated based upon the relative differences in Stokes-Einstein diffusion coefficient. This coefficient specifically affects the passive-diffusive uptake when the interstitial volume and pressure are constant. Parameters such as mean time-to-peak signal, overall fluorescence signal intensities, and number of active peristaltic pulses, were estimated from temporal imaging data. While the mean time to attain peak signal representative of diffusion-dominated flow in the lymph vessels was 0.6±0.2 min for MB and 8±6 min for IgG, showing a size dependence, the active propulsion rates were 3.4±0.8 pulses/min and 3.3±0.5 pulses/min, respectively, appearing size independent. The propulsion rates for both dyes decreased with clearance from the interstitial injection-site, indicating intrinsic control of the smooth muscles in response to interstitial pressure. This approach to size-comparative agent flow imaging of lymphatic function can enable noninvasive characterization of diseases related to uptake and flow in lymph networks.

Connecting Ellipses to Rectangles in Passive Scalar Transport

NASA Astrophysics Data System (ADS)

Aminian, Manuchehr; Bernardi, Francesca; Camassa, Roberto; Harris, Daniel; McLaughlin, Richard

2017-11-01

We study how passive scalar transport in Poiseuille flow is affected by the shape of the pipe cross section. Our previous results have established nontrivial dependence of the skewness of the tracer distribution upon the pipe shape. Previously, we have studied the families of rectangles and ellipses, with the behavior past diffusive timescales primarily depending on aspect ratio, and the type of geometry being secondary. However, at timescales well before the diffusion timescale, the family of ellipses is distinct compared to rectangles. We investigate this phenomenon by studying a collection of exotic cross sections connecting the ellipses and rectangles, using a combination of theoretical and computational tools.

pH Dependent but not P-gp Dependent Bidirectional Transport Study of S-propranolol: The Importance of Passive Diffusion.

PubMed

Zheng, Yi; Benet, Leslie Z; Okochi, Hideaki; Chen, Xijing

2015-08-01

Recent controversial publications, citing studies purporting to show that P-gp mediates the transport of propranolol, proposed that passive biological membrane transport is negligible. Based on the BDDCS, the extensively metabolized-highly permeable-highly soluble BDDCS class 1 drug, propranolol, shows a high passive permeability at concentrations unrestricted by solubility that can overwhelm any potential transporter effects. Here we reinvestigate the effects of passive diffusion and carrier-mediated transport on S-propranolol. Bidirectional permeability and inhibition of efflux transport studies were carried out in MDCK, MDCK-MDR1 and Caco-2 cell lines at different concentrations. Transcellular permeability studies were conducted at different apical pHs in the rat jejunum Ussing chamber model and PAMPA system. S-propranolol exhibited efflux ratios lower than 1 in MDCK, MDCK-MDR1 and Caco-2 cells. No significant differences of Papp, B->A in the presence and absence of the efflux inhibitor GG918 were observed. However, an efflux ratio of 3.63 was found at apical pH 6.5 with significant decrease in Papp, A->B and increase in Papp, B->A compared to apical pH 7.4 in Caco-2 cell lines. The pH dependent permeability was confirmed in the Ussing chamber model. S-propranolol flux was unchanged during inhibition by verapamil and rifampin. Furthermore, pH dependent permeability was also observed in the PAMPA system. S-propranolol does not exhibit active transport as proposed previously. The "false" positive efflux ratio can be explained by the pH partition theory. As expected, passive diffusion, but not active transport, plays the primary role in the permeability of the BDDCS class 1 drug propranolol.

pH dependent but not P-gp dependent bidirectional transport study of S-propranolol: the importance of passive diffusion

PubMed Central

Zheng, Yi; Benet, Leslie Z.; Okochi, Hideaki; Chen, Xijing

2016-01-01

Purpose Recent controversial publications, citing studies purporting to show that P-gp mediates the transport of propranolol, proposed that passive biological membrane transport is negligible. Based on the BDDCS, the extensively metabolized-highly permeable-highly soluble BDDCS class 1 drug, propranolol, shows a high passive permeability at concentrations unrestricted by solubility that can overwhelm any potential transporter effects. Here we reinvestigate the effects of passive diffusion and carrier-mediated transport on S-propranolol. Methods Bidirectional permeability and inhibition of efflux transport studies were carried out in MDCK, MDCK-MDR1 and Caco-2 cell lines at different concentrations. Transcellular permeability studies were conducted at different apical pHs in the rat jejunum Ussing chamber model and PAMPA system. Results S-propranolol exhibited efflux ratios lower than 1 in MDCK, MDCK-MDR1 and Caco-2 cells. No significant differences of Papp, B->A in the presence and absence of the efflux inhibitor GG918 were observed. However, an efflux ratio of 3.63 was found at apical pH 6.5 with significant decrease in Papp, A->B and increase in Papp, B->A compared to apical pH 7.4 in Caco-2 cell lines. The pH dependent permeability was confirmed in the Ussing chamber model. S-propranolol flux was unchanged during inhibition by verapamil and rifampin. Furthermore, pH dependent permeability was also observed in the PAMPA system. Conclusions S-propranolol does not exhibit active transport as proposed previously. The "false" positive efflux ratio can be explained by the pH partition theory. As expected, passive diffusion, but not active transport, plays the primary role in the permeability of the BDDCS class 1 drug propranolol. PMID:25690341

Passivation Using Molecular Halides Increases Quantum Dot Solar Cell Performance.

PubMed

Lan, Xinzheng; Voznyy, Oleksandr; Kiani, Amirreza; García de Arquer, F Pelayo; Abbas, Abdullah Saud; Kim, Gi-Hwan; Liu, Mengxia; Yang, Zhenyu; Walters, Grant; Xu, Jixian; Yuan, Mingjian; Ning, Zhijun; Fan, Fengjia; Kanjanaboos, Pongsakorn; Kramer, Illan; Zhitomirsky, David; Lee, Philip; Perelgut, Alexander; Hoogland, Sjoerd; Sargent, Edward H

2016-01-13

A solution-based passivation scheme is developed featuring the use of molecular iodine and PbS colloidal quantum dots (CQDs). The improved passivation translates into a longer carrier diffusion length in the solid film. This allows thicker solar-cell devices to be built while preserving efficient charge collection, leading to a certified power conversion efficiency of 9.9%, which is a new record in CQD solar cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Activation energies of diffusion of organic migrants in cyclo olefin polymer.

PubMed

Welle, Frank

2014-10-01

Cyclo olefin polymer (COP) is an amorphous polymer with good optical transparency and barrier properties, which is increasingly used for pharmaceutical packaging applications like pre-filled syringes, plastic vials, nutrition bags and blisters as well as for micro-well plates. For regulatory purposes, it is important to know the amount and quantity of compounds which migrate from the polymer into the pharmaceutical product. Within the study, diffusion coefficients of organic (model) compounds in COP at various temperatures were determined and the activation energies of diffusion were calculated according to the Arrhenius approach. Correlations were established between the molecular volume V of the migrating compound and the activation energy of diffusion EA as well as between the pre-exponential factor in the Arrhenius equation D0 and EA. From these correlations a prediction model was established for the migration of organic compounds in COP. This might be a useful tool supporting the evaluation process of COP packed pharmaceutical products. Copyright © 2014 Elsevier B.V. All rights reserved.

Li4SiO4-Based Artificial Passivation Thin Film for Improving Interfacial Stability of Li Metal Anodes.

PubMed

Kim, Ji Young; Kim, A-Young; Liu, Guicheng; Woo, Jae-Young; Kim, Hansung; Lee, Joong Kee

2018-03-14

An amorphous SiO 2 (a-SiO 2 ) thin film was developed as an artificial passivation layer to stabilize Li metal anodes during electrochemical reactions. The thin film was prepared using an electron cyclotron resonance-chemical vapor deposition apparatus. The obtained passivation layer has a hierarchical structure, which is composed of lithium silicide, lithiated silicon oxide, and a-SiO 2 . The thickness of the a-SiO 2 passivation layer could be varied by changing the processing time, whereas that of the lithium silicide and lithiated silicon oxide layers was almost constant. During cycling, the surface of the a-SiO 2 passivation layer is converted into lithium silicate (Li 4 SiO 4 ), and the portion of Li 4 SiO 4 depends on the thickness of a-SiO 2 . A minimum overpotential of 21.7 mV was observed at the Li metal electrode at a current density of 3 mA cm -2 with flat voltage profiles, when an a-SiO 2 passivation layer of 92.5 nm was used. The Li metal with this optimized thin passivation layer also showed the lowest charge-transfer resistance (3.948 Ω cm) and the highest Li ion diffusivity (7.06 × 10 -14 cm 2 s -1 ) after cycling in a Li-S battery. The existence of the Li 4 SiO 4 artificial passivation layer prevents the corrosion of Li metal by suppressing Li dendritic growth and improving the ionic conductivity, which contribute to the low charge-transfer resistance and high Li ion diffusivity of the electrode.

Developing a new, passive diffusion sampling array to detect helium anomalies associated with volcanic unrest

USGS Publications Warehouse

Dame, Brittany E; Solomon, D Kip; Evans, William C.; Ingebritsen, Steven E.

2015-01-01

Helium (He) concentration and 3 He/ 4 He anomalies in soil gas and spring water are potentially powerful tools for investigating hydrothermal circulation associated with volca- nism and could perhaps serve as part of a hazards warning system. However, in operational practice, He and other gases are often sampled only after volcanic unrest is detected by other means. A new passive diffusion sampler suite, intended to be collected after the onset of unrest, has been developed and tested as a relatively low-cost method of determining He- isotope composition pre- and post-unrest. The samplers, each with a distinct equilibration time, passively record He concen- tration and isotope ratio in springs and soil gas. Once collected and analyzed, the He concentrations in the samplers are used to deconvolve the time history of the He concentration and the 3 He/ 4 He ratio at the collection site. The current suite consisting of three samplers is sufficient to deconvolve both the magnitude and the timing of a step change in in situ con- centration if the suite is collected within 100 h of the change. The effects of temperature and prolonged deployment on the suite ’ s capability of recording He anomalies have also been evaluated. The suite has captured a significant 3 He/ 4 He soil gas anomaly at Horseshoe Lake near Mammoth Lakes, California. The passive diffusion sampler suite appears to be an accurate and affordable alternative for determining He anomalies associated with volcanic unrest.

Dioxin analysis in water by using a passive sampler and CALUX bioassay.

PubMed

Addeck, Amr; Croes, Kim; Van Langenhove, Kersten; Denison, Michael; Elskens, Marc; Baeyens, Willy

2012-01-15

Passive sampling of organic pollutants is a new trend in environmental monitoring and analysis. Passive samplers are being developed to overcome the drawbacks of the conventional snapshot sampling approach. The ceramic toximeter is a promising passive sampler for monitoring dioxin-contaminated surface and ground waters. It consists of an alumina cylinder lined with a thin coating of titania and a pore diameter of 0.05 μm. The cylinder serves as a diffusion barrier limiting the analyte transport to molecular diffusion only, as well as a container for a selective trapping material of a high capacity and affinity towards the chemical(s) of concern. The cylinder is closed from both sides with PTFE caps. The ceramic toximeter was filled with activated carbon as the trapping material and has been tested in vitro for the sampling of dioxin-contaminated water. In addition, the utilization of the CALUX bioassay technique for analyzing the trapped dioxin has greatly reduced the time and costs for dioxin scanning in aqueous media. Exposure times varied between 1 and 7 days in a solution of 1.35 ng-TCDDL(-1) (TCDD is 2,3,7,8-tetrachlorodibenzodioxin). The mean effective molecular diffusion coefficient of TCDD in the toximeter amounts to 11.9×10(-6)m(2)d(-1) while the minimum concentration detectable in an aquatic system after 30 days of exposure amounts to 0.89 pg-TCDDL(-1). Copyright © 2011 Elsevier B.V. All rights reserved.

Effects of different cooling treatments on water diffusion, microcirculation, and water content within exercised muscles: evaluation by magnetic resonance T2-weighted and diffusion-weighted imaging.

PubMed

Yanagisawa, Osamu; Takahashi, Hideyuki; Fukubayashi, Toru

2010-09-01

In this study, we determined the effects of different cooling treatments on exercised muscles. Seven adults underwent four post-exercise treatments (20-min ice-bag application, 60-min gel-pack application at 10 degrees C and 17 degrees C, and non-cooling treatment) with at least 1 week between treatments. Magnetic resonance diffusion- and T2-weighted images were obtained to calculate the apparent diffusion coefficients (apparent diffusion coefficient 1, which reflects intramuscular water diffusion and microcirculation, and apparent diffusion coefficient 2, which is approximately equal to the true diffusion coefficient that excludes as much of the effect of intramuscular microcirculation as possible) and the T2 values (intramuscular water content level) of the ankle dorsiflexors, respectively, before and after ankle dorsiflexion exercise and after post-exercise treatment. The T2 values increased significantly after exercise and returned to pre-exercise values after each treatment; no significant differences were observed among the four post-exercise treatments. Both apparent diffusion coefficients also increased significantly after exercise and decreased significantly after the three cooling treatments; no significant difference was detected among the three cooling treatments. Local cooling suppresses both water diffusion and microcirculation within exercised muscles. Moreover, although the treatment time was longer, adequate cooling effects could be achieved using the gel-pack applications at relatively mild cooling temperatures.

Calculating the Diffusive Flux of Persistent Organic Pollutants between Sediments and the Water Column on the Palos Verdes Shelf Superfund Site using Polymeric Passive Samplers

EPA Science Inventory

Passive samplers were used to determine water concentrations of persistent organic pollutants (POPs) in the surface sediments and near-bottom water of a marine Superfund site on the Palos Verdes Shelf, California, USA. Measured concentrations in the porewater and water column at...

Measurement of VOCs Using Passive Sorbent Tubes near Oil & Natural Gas Production Pads in Colorado and Texas

EPA Science Inventory

A U.S. EPA team, consisting of the Office of Research and Development and Region 6 (Dallas) and Region 8 (Denver), deployed passive-diffusive sorbent tubes as part of a method evaluation study around one oil and natural gas production pad in both the Barnett Shale Basin in Texas ...

Wavelength Coded Image Transmission and Holographic Optical Elements.

DTIC Science & Technology

1984-08-20

system has been designed and built for transmitting images of diffusely reflecting objects through optical fibers and displaying those images at a...passive components at the end of a fiber-optic designed to transmit high-resolution images of diffusely imaging system as described in this paper... designing a system for viewing diffusely reflecting The authors are with University of Minnesota. Electrical Engi- objects, one must consider that a

Diffusion-limited mixing by incompressible flows

NASA Astrophysics Data System (ADS)

Miles, Christopher J.; Doering, Charles R.

2018-05-01

Incompressible flows can be effective mixers by appropriately advecting a passive tracer to produce small filamentation length scales. In addition, diffusion is generally perceived as beneficial to mixing due to its ability to homogenize a passive tracer. However we provide numerical evidence that, in cases where advection and diffusion are both actively present, diffusion may produce negative effects by limiting the mixing effectiveness of incompressible optimal flows. This limitation appears to be due to the presence of a limiting length scale given by a generalised Batchelor length (Batchelor 1959 J. Fluid Mech. 5 113–33). This length scale limitation may in turn affect long-term mixing rates. More specifically, we consider local-in-time flow optimisation under energy and enstrophy flow constraints with the objective of maximising the mixing rate. We observe that, for enstrophy-bounded optimal flows, the strength of diffusion may not impact the long-term mixing rate. For energy-constrained optimal flows, however, an increase in the strength of diffusion can decrease the mixing rate. We provide analytical lower bounds on mixing rates and length scales achievable under related constraints (point-wise bounded speed and rate-of-strain) by extending the work of Lin et al (2011 J. Fluid Mech. 675 465–76) and Poon (1996 Commun. PDE 21 521–39).

A DNS study of turbulent mixing of two passive scalars

NASA Astrophysics Data System (ADS)

Juneja, A.; Pope, S. B.

1996-08-01

We employ direct numerical simulations to study the mixing of two passive scalars in stationary, homogeneous, isotropic turbulence. The present work is a direct extension of that of Eswaran and Pope from one scalar to two scalars and the focus is on examining the evolution states of the scalar joint probability density function (jpdf) and the conditional expectation of the scalar diffusion to motivate better models for multi-scalar mixing. The initial scalar fields are chosen to conform closely to a ``triple-delta function'' jpdf corresponding to blobs of fluid in three distinct states. The effect of the initial length scales and diffusivity of the scalars on the evolution of the jpdf and the conditional diffusion is investigated in detail as the scalars decay from their prescribed initial state. Also examined is the issue of self-similarity of the scalar jpdf at large times and the rate of decay of the scalar variance and dissipation.

Laser doping of boron-doped Si paste for high-efficiency silicon solar cells

NASA Astrophysics Data System (ADS)

Tomizawa, Yuka; Imamura, Tetsuya; Soeda, Masaya; Ikeda, Yoshinori; Shiro, Takashi

2015-08-01

Boron laser doping (LD) is a promising technology for high-efficiency solar cells such as p-type passivated locally diffused solar cells and n-type Si-wafer-based solar cells. We produced a printable phosphorus- or boron-doped Si paste (NanoGram® Si paste/ink) for use as a diffuser in the LD process. We used the boron LD process to fabricate high-efficiency passivated emitter and rear locally diffused (PERL) solar cells. PERL solar cells on Czochralski Si (Cz-Si) wafers yielded a maximum efficiency of 19.7%, whereas the efficiency of a reference cell was 18.5%. Fill factors above 79% and open circuit voltages above 655 mV were measured. We found that the boron-doped area effectively performs as a local boron back surface field (BSF). The characteristics of the solar cell formed using NanoGram® Si paste/ink were better than those of the reference cell.

Anomalous scaling of passive scalars in rotating flows.

PubMed

Rodriguez Imazio, P; Mininni, P D

2011-06-01

We present results of direct numerical simulations of passive scalar advection and diffusion in turbulent rotating flows. Scaling laws and the development of anisotropy are studied in spectral space, and in real space using an axisymmetric decomposition of velocity and passive scalar structure functions. The passive scalar is more anisotropic than the velocity field, and its power spectrum follows a spectral law consistent with ~ k[Please see text](-3/2). This scaling is explained with phenomenological arguments that consider the effect of rotation. Intermittency is characterized using scaling exponents and probability density functions of velocity and passive scalar increments. In the presence of rotation, intermittency in the velocity field decreases more noticeably than in the passive scalar. The scaling exponents show good agreement with Kraichnan's prediction for passive scalar intermittency in two dimensions, after correcting for the observed scaling of the second-order exponent.

Arctic sea-ice diffusion from observed and simulated Lagrangian trajectories

NASA Astrophysics Data System (ADS)

Rampal, Pierre; Bouillon, Sylvain; Bergh, Jon; Ólason, Einar

2016-07-01

We characterize sea-ice drift by applying a Lagrangian diffusion analysis to buoy trajectories from the International Arctic Buoy Programme (IABP) dataset and from two different models: the standalone Lagrangian sea-ice model neXtSIM and the Eulerian coupled ice-ocean model used for the TOPAZ reanalysis. By applying the diffusion analysis to the IABP buoy trajectories over the period 1979-2011, we confirm that sea-ice diffusion follows two distinct regimes (ballistic and Brownian) and we provide accurate values for the diffusivity and integral timescale that could be used in Eulerian or Lagrangian passive tracers models to simulate the transport and diffusion of particles moving with the ice. We discuss how these values are linked to the evolution of the fluctuating displacements variance and how this information could be used to define the size of the search area around the position predicted by the mean drift. By comparing observed and simulated sea-ice trajectories for three consecutive winter seasons (2007-2011), we show how the characteristics of the simulated motion may differ from or agree well with observations. This comparison illustrates the usefulness of first applying a diffusion analysis to evaluate the output of modeling systems that include a sea-ice model before using these in, e.g., oil spill trajectory models or, more generally, to simulate the transport of passive tracers in sea ice.

Bed bug aggregation on dirty laundry: a mechanism for passive dispersal.

PubMed

Hentley, William T; Webster, Ben; Evison, Sophie E F; Siva-Jothy, Michael T

2017-09-28

Bed bugs have shown a recent and rapid global expansion that has been suggested to be caused by cheap air travel. How a small, flightless and anachoretic insect that hides within its host's sleeping area manages to travel long distances is not yet clear. Bed bugs are attracted to the odour of sleeping humans and we suggest that soiled clothing may present a similarly attractive cue, allowing bed bugs to 'hitch-hike' around the world after aggregating in the laundry bags of travellers. We show that (1) soiled clothing is significantly more attractive than clean clothing to active bed bugs moving within a bedroom sized arena and (2) elevation of CO 2 to a level that simulates human occupancy in the same arena appears to initiate search behaviour rather than direct it. Our results show, for the first time, how leaving worn clothing exposed in sleeping areas when travelling can be exploited by bed bugs to facilitate passive dispersal.

Multigrid techniques for the solution of the passive scalar advection-diffusion equation

NASA Technical Reports Server (NTRS)

Phillips, R. E.; Schmidt, F. W.

1985-01-01

The solution of elliptic passive scalar advection-diffusion equations is required in the analysis of many turbulent flow and convective heat transfer problems. The accuracy of the solution may be affected by the presence of regions containing large gradients of the dependent variables. The multigrid concept of local grid refinement is a method for improving the accuracy of the calculations in these problems. In combination with the multilevel acceleration techniques, an accurate and efficient computational procedure is developed. In addition, a robust implementation of the QUICK finite-difference scheme is described. Calculations of a test problem are presented to quantitatively demonstrate the advantages of the multilevel-multigrid method.

How does passive lengthening change the architecture of the human medial gastrocnemius muscle?

PubMed

Bolsterlee, Bart; D'Souza, Arkiev; Gandevia, Simon C; Herbert, Robert D

2017-04-01

There are few comprehensive investigations of the changes in muscle architecture that accompany muscle contraction or change in muscle length in vivo. For this study, we measured changes in the three-dimensional architecture of the human medial gastrocnemius at the whole muscle level, the fascicle level and the fiber level using anatomical MRI and diffusion tensor imaging (DTI). Data were obtained from eight subjects under relaxed conditions at three muscle lengths. At the whole muscle level, a 5.1% increase in muscle belly length resulted in a reduction in both muscle width (mean change -2.5%) and depth (-4.8%). At the fascicle level, muscle architecture measurements obtained at 3,000 locations per muscle showed that for every millimeter increase in muscle-tendon length above the slack length, average fascicle length increased by 0.46 mm, pennation angle decreased by 0.27° (0.17° in the superficial part and 0.37° in the deep part), and fascicle curvature decreased by 0.18 m -1 There was no evidence of systematic variation in architecture along the muscle's long axis at any muscle length. At the fiber level, analysis of the diffusion signal showed that passive lengthening of the muscle increased diffusion along fibers and decreased diffusion across fibers. Using these measurements across scales, we show that the complex shape changes that muscle fibers, whole muscles, and aponeuroses of the medial gastrocnemius undergo in vivo cannot be captured by simple geometrical models. This justifies the need for more complex models that link microstructural changes in muscle fibers to macroscopic changes in architecture. NEW & NOTEWORTHY Novel MRI and DTI techniques revealed changes in three-dimensional architecture of the human medial gastrocnemius during passive lengthening. Whole muscle belly width and depth decreased when the muscle lengthened. Fascicle length, pennation, and curvature changed uniformly or near uniformly along the muscle during passive lengthening. Diffusion of water molecules in muscle changes in the same direction as fascicle strains. Copyright © 2017 the American Physiological Society.

Enhanced diffusion of pollutants by self-propulsion.

PubMed

Zhao, Guanjia; Stuart, Emma J E; Pumera, Martin

2011-07-28

Current environmental models mostly account for the passive participation of pollutants in their environmental propagation. Here we demonstrate the paradigm-changing concept that pollutants can propagate themselves with a rate that is greater than the rate for standard molecular diffusion by five orders of magnitude. This journal is © the Owner Societies 2011

Calibration of passive remote observing optical and microwave instrumentation; Proceedings of the Meeting, Orlando, FL, Apr. 3-5, 1991

NASA Technical Reports Server (NTRS)

Guenther, Bruce W. (Editor)

1991-01-01

Various papers on the calibration of passive remote observing optical and microwave instrumentation are presented. Individual topics addressed include: on-board calibration device for a wide field-of-view instrument, calibration for the medium-resolution imaging spectrometer, cryogenic radiometers and intensity-stabilized lasers for EOS radiometric calibrations, radiometric stability of the Shuttle-borne solar backscatter ultraviolet spectrometer, ratioing radiometer for use with a solar diffuser, requirements of a solar diffuser and measurements of some candidate materials, reflectance stability analysis of Spectralon diffuse calibration panels, stray light effects on calibrations using a solar diffuser, radiometric calibration of SPOT 23 HRVs, surface and aerosol models for use in radiative transfer codes. Also addressed are: calibrated intercepts for solar radiometers used in remote sensor calibration, radiometric calibration of an airborne multispectral scanner, in-flight calibration of a helicopter-mounted Daedalus multispectral scanner, technique for improving the calibration of large-area sphere sources, remote colorimetry and its applications, spatial sampling errors for a satellite-borne scanning radiometer, calibration of EOS multispectral imaging sensors and solar irradiance variability.

Uptake of 2, 4-Dichlorophenoxyacetic acid by Pseudomonas fluorescens

USGS Publications Warehouse

Wedemeyer, G.A.

1966-01-01

Factors influencing the uptake of the sodium salt of 2,4-dichlorophenoxyacetic acid (2,4-D), under conditions in which no net metabolism occurred, were investigated in an effort to determine both the significance of “nonmetabolic” uptake as a potential agent in reducing pesticide levels and the mechanisms involved. Uptake of 2,4-D was affected by pH, temperature, and the presence of other organic and inorganic compounds. Uptake was more pronounced at pH values less than 6, which implies that there may be some interaction between charged groups on the cell and the ionized carboxyl group of 2,4-D. Active transport, carriermediated diffusion, passive diffusion, and adsorption were considered as possible mechanisms. Though uptake was inhibited by glucose, sodium azide, and fluorodinitrobenzene (but not by uranylion), 2,4-D was not accumulated against a concentration gradient, a necessary consequence of an active transport system, nor was isotope counterflow found to occur. Thus, carrier-mediated diffusion was finally precluded, implying that uptake probably occurs by a two-step process: sorption onto the cell wall followed by passive diffusion into the cytoplasm.

Uptake of 2,4-dichlorophenoxyacetic acid by Pseudomonas fluorescens

USGS Publications Warehouse

Wedemeyer, Gary

1966-01-01

Factors influencing the uptake of the sodium salt of 2,4-dichlorophenoxyacetic acid (2,4-D), under conditions in which no net metabolism occurred, were investigated in an effort to determine both the significance of “non-metabolic” uptake as a potential agent in reducing pesticide levels and the mechanisms involved. Uptake of 2,4-D was affected by pH, temperature, and the presence of other organic and inorganic compounds. Uptake was more pronounced at pH values less than 6, which implies that there may be some interaction between charged groups on the cell and the ionized carboxyl group of 2,4-D. Active transport, carrier-mediated diffusion, passive diffusion, and adsorption were considered as possible mechanisms. Though uptake was inhibited by glucose, sodium azide, and fluorodinitrobenzene (but not by uranyl ion), 2,4-D was not accumulated against a concentration gradient, a necessary consequence of an active transport system, nor was isotope counterflow found to occur. Thus, carrier-mediated diffusion was finally precluded, implying that uptake probably occurs by a two-step process: sorption onto the cell wall followed by passive diffusion into the cytoplasm.

Fenceline Measurements of Speciated VOCs Using Passive Sorbent Tubes Deployed Around Oil and Natural Gas Production Pads in Colorado and Texas

EPA Science Inventory

A U.S. EPA team, consisting of the Office of Research and Development and Region 6 (Dallas) and Region 8 (Denver), deployed passive-diffusive sorbent tubes as part of a method evaluation study around one oil and natural gas production pad in both the Barnett Shale Basin in Texas ...

Mathematical modelling of the Phloem: the importance of diffusion on sugar transport at osmotic equilibrium.

PubMed

Payvandi, S; Daly, K R; Zygalakis, K C; Roose, T

2014-11-01

Plants rely on the conducting vessels of the phloem to transport the products of photosynthesis from the leaves to the roots, or to any other organs, for growth, metabolism, and storage. Transport within the phloem is due to an osmotically-generated pressure gradient and is hence inherently nonlinear. Since convection dominates over diffusion in the main bulk flow, the effects of diffusive transport have generally been neglected by previous authors. However, diffusion is important due to boundary layers that form at the ends of the phloem, and at the leaf-stem and stem-root boundaries. We present a mathematical model of transport which includes the effects of diffusion. We solve the system analytically in the limit of high Münch number which corresponds to osmotic equilibrium and numerically for all parameter values. We find that the bulk solution is dependent on the diffusion-dominated boundary layers. Hence, even for large Péclet number, it is not always correct to neglect diffusion. We consider the cases of passive and active sugar loading and unloading. We show that for active unloading, the solutions diverge with increasing Péclet. For passive unloading, the convergence of the solutions is dependent on the magnitude of loading. Diffusion also permits the modelling of an axial efflux of sugar in the root zone which may be important for the growing root tip and for promoting symbiotic biological interactions in the soil. Therefore, diffusion is an essential mechanism for transport in the phloem and must be included to accurately predict flow.

Mechanisms of Ocean Heat Uptake

NASA Astrophysics Data System (ADS)

Garuba, Oluwayemi

An important parameter for the climate response to increased greenhouse gases or other radiative forcing is the speed at which heat anomalies propagate downward in the ocean. Ocean heat uptake occurs through passive advection/diffusion of surface heat anomalies and through the redistribution of existing temperature gradients due to circulation changes. Atlantic meridional overturning circulation (AMOC) weakens in a warming climate and this should slow the downward heat advection (compared to a case in which the circulation is unchanged). However, weakening AMOC also causes a deep warming through the redistributive effect, thus increasing the downward rate of heat propagation compared to unchanging circulation. Total heat uptake depends on the combined effect of these two mechanisms. Passive tracers in a perturbed CO2 quadrupling experiments are used to investigate the effect of passive advection and redistribution of temperature anomalies. A new passive tracer formulation is used to separate ocean heat uptake into contributions due to redistribution and passive advection-diffusion of surface heating during an ocean model experiment with abrupt increase in surface temperature. The spatial pattern and mechanisms of each component are examined. With further experiments, the effects of surface wind, salinity and temperature changes in changing circulation and the resulting effect on redistribution in the individual basins are isolated. Analysis of the passive advection and propagation path of the tracer show that the Southern ocean dominates heat uptake, largely through vertical and horizontal diffusion. Vertical diffusion transports the tracer across isopycnals down to about 1000m in 100 years in the Southern ocean. Advection is more important in the subtropical cells and in the Atlantic high latitudes, both with a short time scale of about 20 years. The shallow subtropical cells transport the tracer down to about 500m along isopycnal surfaces, below this vertical diffusion takes over transport in the tropics; in the Atlantic, the MOC transports heat as deep 2000m in about 30 years. Redistributive surface heat uptake alters the total amount surface heat uptake among the basins. Compared to the passive-only heat uptake, which is about the same among the basins, redistribution nearly doubles the surface heat input into the Atlantic but makes smaller increases in the Indian and Pacific oceans for a net global increase of about 25%, in the perturbation experiment with winds unchanged. The passive and redistributive heat uptake components are further distributed among the basins through the global conveyor belt. The Pacific gains twice the surface heat input into it through lateral transport from the other two basins, as a result, the Atlantic and Pacific gain similar amounts of heat even though surface heat input is in the Atlantic is much bigger. Of this heat transport, most of the passive component comes from the Indian and the redistributive component comes from the Atlantic. Different surface forcing perturbation gives different circulation change pattern and as a result yield different redistributive uptake. Ocean heat uptake is more sensitive to wind forcing perturbation than to thermohaline forcing perturbation. About 2% reduction in subtropical cells transport and southern ocean transport, in the wind-change perturbation experiment, resulted in about 10% reduction in the global ocean heat uptake of wind-unchanged experiment. The AMOC weakened by about 35% and resulted in a 25% increase in passive heat uptake in the wind-unchanged experiment. Surface winds weakening reduces heat uptake by warming the reservoir surface temperatures, while MOC weakening increases heat input by a cooling reservoir surface temperatures. Thermohaline forcing perturbation is combination of salinity and temperature perturbations, both weaken the AMOC, however, they have opposite redistributive effects. Ocean surface freshening gives positive redistributive effect, while surface temperature increase gives negative redistributive effect on heat uptake. The salinity effect dominates the redistributive effect for thermohaline perturbation.

Modeling uptake of hydrophobic organic contaminants into polyethylene passive samplers.

PubMed

Thompson, Jay M; Hsieh, Ching-Hong; Luthy, Richard G

2015-02-17

Single-phase passive samplers are gaining acceptance as a method to measure hydrophobic organic contaminant (HOC) concentration in water. Although the relationship between the HOC concentration in water and passive sampler is linear at equilibrium, mass transfer models are needed for nonequilibrium conditions. We report measurements of organochlorine pesticide diffusion and partition coefficients with respect to polyethylene (PE), and present a Fickian approach to modeling HOC uptake by PE in aqueous systems. The model is an analytic solution to Fick's second law applied through an aqueous diffusive boundary layer and a polyethylene layer. Comparisons of the model with existing methods indicate agreement at appropriate boundary conditions. Laboratory release experiments on the organochlorine pesticides DDT, DDE, DDD, and chlordane in well-mixed slurries support the model's applicability to aqueous systems. In general, the advantage of the model is its application in the cases of well-agitated systems, low values of polyethylene-water partioning coefficients, thick polyethylene relative to the boundary layer thickness, and/or short exposure times. Another significant advantage is the ability to estimate, or at least bound, the needed exposure time to reach a desired CPE without empirical model inputs. A further finding of this work is that polyethylene diffusivity does not vary by transport direction through the sampler thickness.

Measurement of minority carrier diffusion lengths in GaAs nanowires by a nanoprobe technique

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

Darbandi, A.; Watkins, S. P., E-mail: simonw@sfu.ca

Minority carrier diffusion lengths in both p-type and n-type GaAs nanowires were studied using electron beam induced current by means of a nanoprobe technique without lithographic processing. The diffusion lengths were determined for Au/GaAs rectifying junctions as well as axial p-n junctions. By incorporating a thin lattice-matched InGaP passivating shell, a 2-fold enhancement in the minority carrier diffusion lengths and one order of magnitude reduction in the surface recombination velocity were achieved.

A new passive radon-thoron discriminative measurement system.

PubMed

Sciocchetti, G; Sciocchetti, A; Giovannoli, P; DeFelice, P; Cardellini, F; Cotellessa, G; Pagliari, M

2010-10-01

A new passive radon-thoron discriminative measurement system has been developed for monitoring radon and thoron individually. It consists of a 'couple' of passive integrating devices with a CR39 nuclear track detector (NTD). The experimental prototype is based on the application of a new concept of NTD instrument developed at ENEA, named Alpha-PREM, acronym of piston radon exposure meter, which allows controlling the detector exposure with a patented sampling technique (Int. Eu. Pat. and US Pat.). The 'twin diffusion chambers system' was based on two A-PREM devices consisting of the standard device, named NTD-Rn, and a modified version, named NTD-Rn/Tn, which was set up to improve thoron sampling efficiency of the diffusion chamber, without changing the geometry and the start/stop function of the NTD-Rn device. Coupling devices fitted on each device allowed getting a system, which works as a double-chamber structure when deployed at the monitoring position. In this paper both technical and physical aspects are considered.

A novel in-plane passive microfluidic mixer with modified Tesla structures.

PubMed

Hong, Chien-Chong; Choi, Jin-Woo; Ahn, Chong H

2004-04-01

An innovative in-plane passive micromixer using modified Tesla structures, which are used as passive valves, has been designed, simulated, fabricated and successfully characterized in this paper. Simulation and experimental results of the developed novel micromixer have shown excellent mixing performance over a wide range of flow conditions in the micro scale. The micromixer realized in this work has achieved even better mixing performance at a higher flow rate, and its pressure drop is less than 10 KPa at the flow rate of 100 microl min(-1). This micromixer shows characteristics similar to Taylor dispersion, with contributions from both diffusion and convection. The mixer has a diffusion domain region at low flow rate, but it moves to a convection domain region at high flow rate. Due to the simple in-plane structure of the novel micromixer explored in this work, the mixer can be easily realized and integrated with on-chip microfluidic devices and micro total analysis systems (micro-TAS).

Performance evaluation of a tailor-made passive sampler for monitoring of tropospheric ozone.

PubMed

Ozden, Ozlem; Döğeroğlu, Tuncay

2012-09-01

This study presents the performance evaluation of a tailor-made passive sampler developed for the monitoring of tropospheric ozone. The performance of the passive sampler was tested in the field conditions in terms of accuracy, precision, blank values, detection limit, effects of some parameters such as sampling site characteristics and sampling period on the field blanks, self-consistency, experimental and theoretical uptake rates, shelf life and comparison with commercial passive samplers. There was an agreement (R (2) = 0.84) between the responses of passive sampler and the continuous automatic analyser. The accuracy of the sampler, expressed as percent relative error, was obtained lower than 15%. Method precision in terms of coefficient of variance for three simultaneously applied passive samplers was 12%. Sampler detection limit was 2.42 μg m(-3) for an exposure period of 1 week, and the sampler can be stored safely for a period of up to 8 weeks before exposure. Satisfactory self-consistency results showed that extended periods gave the same integrated response as a series of short-term samplers run side by side. The uptake rate of ozone was found to be 10.21 mL min(-1) in a very good agreement with the theoretical uptake rate (10.32 mL min(-1)). The results of the comparison study conducted against a commercially available diffusion tube (Gradko diffusion tube) showed a good linear relationship (R (2) = 0.93) between two passive samplers. The sampler seems suitable to be used in large-scale measurements of ozone where no data are available or the number of existing automated monitors is not sufficient.

Stirring Up the Biological Pump: Vertical Mixing and Carbon Export in the Southern Ocean

NASA Astrophysics Data System (ADS)

Stukel, Michael R.; Ducklow, Hugh W.

2017-09-01

The biological carbon pump (BCP) transports organic carbon from the surface to the ocean's interior via sinking particles, vertically migrating organisms, and passive transport of organic matter by advection and diffusion. While many studies have quantified sinking particles, the magnitude of passive transport remains poorly constrained. In the Southern Ocean weak thermal stratification, strong vertical gradients in particulate organic matter, and weak vertical nitrate gradients suggest that passive transport from the euphotic zone may be particularly important. We compile data from seasonal time series at a coastal site near Palmer Station, annual regional cruises in the Western Antarctic Peninsula (WAP), cruises throughout the broader Southern Ocean, and SOCCOM (Southern Ocean Carbon and Climate Observations and Modeling) autonomous profiling floats to estimate spatial and temporal patterns in vertical gradients of nitrate, particulate nitrogen (PN), and dissolved organic carbon. Under a steady state approximation, the ratio of ∂PN/∂z to ∂NO3-/∂z suggests that passive transport of PN may be responsible for removing 46% (37%-58%) of the nitrate introduced into the surface ocean of the WAP (with dissolved organic matter contributing an additional 3-6%) and for 23% (19%-28%) of the BCP in the broader Southern Ocean. A simple model parameterized with in situ nitrate, PN, and primary production data suggested that passive transport was responsible for 54% of the magnitude of the BCP in the WAP. Our results highlight the potential importance of passive transport (by advection and diffusion) of organic matter in the Southern Ocean but should only be considered indicative of high passive transport (rather than conclusive evidence) due to our steady state assumptions.

Status and Progress of High-efficiency Silicon Solar Cells

NASA Astrophysics Data System (ADS)

Xiao, Shaoqing; Xu, Shuyan

High-efficiency Si solar cells have attracted more and more attention from researchers, scientists, engineers of photovoltaic (PV) industry for the past few decades. Many high-quality researchers and engineers in both academia and industry seek solutions to improve the cell efficiency and reduce the cost. This desire has stimulated a growing number of major research and research infrastructure programmes, and a rapidly increasing number of publications in this filed. This chapter reviews materials, devices and physics of high-efficiency Si solar cells developed over the last 20 years. In this chapter there is a fair number of topics, not only from the material viewpoint, introducing various materials that are required for high-efficiency Si solar cells, such as base materials (FZ-Si, CZ-Si, MCZ-Si and multi-Si), emitter materials (diffused emitter and deposited emitter), passivation materials (Al-back surface field, high-low junction, SiO2, SiO x , SiN x , Al2O3 and a-Si:H), and other functional materials (antireflective layer, TCO and metal electrode), but also from the device and physics point of view, elaborating on physics, cell concept, development and status of all kinds of high-efficiency Si solar cells, such as passivated emitter and rear contact (PERC), passivated emitter and rear locally diffused (PERL), passivated emitter and rear totally diffused (PERT), Pluto, interdigitated back-contacted (IBC), emitter-wrap-through (EWT), metallization-wrap-through (MWT), Heterojunction with intrinsic thin-layer (HIT) and so on. Some representative examples of high-efficiency Si solar cell materials and devices with excellent performance and competitive advantages are presented.

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

Willemin, Marie-Emilie; Lumen, Annie, E-mail: Anni

Thyroid homeostasis can be disturbed due to thiocyanate exposure from the diet or tobacco smoke. Thiocyanate inhibits both thyroidal uptake of iodide, via the sodium-iodide symporter (NIS), and thyroid hormone (TH) synthesis in the thyroid, via thyroid peroxidase (TPO), but the mode of action of thiocyanate is poorly quantified in the literature. The characterization of the link between intra-thyroidal thiocyanate concentrations and dose of exposure is crucial for assessing the risk of thyroid perturbations due to thiocyanate exposure. We developed a PBPK model for thiocyanate that describes its kinetics in the whole-body up to daily doses of 0.15 mmol/kg, withmore » a mechanistic description of the thyroidal kinetics including NIS, passive diffusion, and TPO. The model was calibrated in a Bayesian framework using published studies in rats. Goodness-of-fit was satisfactory, especially for intra-thyroidal thiocyanate concentrations. Thiocyanate kinetic processes were quantified in vivo, including the metabolic clearance by TPO. The passive diffusion rate was found to be greater than NIS-mediated uptake rate. The model captured the dose-dependent kinetics of thiocyanate after acute and chronic exposures. Model behavior was evaluated using a Morris screening test. The distribution of thiocyanate into the thyroid was found to be determined primarily by the partition coefficient, followed by NIS and passive diffusion; the impact of the latter two mechanisms appears to increase at very low doses. Extrapolation to humans resulted in good predictions of thiocyanate kinetics during chronic exposure. The developed PBPK model can be used in risk assessment to quantify dose-response effects of thiocyanate on TH. - Highlights: • A PBPK model of thiocyanate (SCN{sup −}) was calibrated in rats in a Bayesian framework. • The intra-thyroidal kinetics of thiocyanate including NIS and TPO was modeled. • Passive diffusion rate for SCN{sup −} seemed to be greater than the NIS-mediated uptake. • The dose-dependent kinetics of SCN{sup −} was captured after an acute and chronic exposure. • The PBPK model of thiocyanate was successfully extrapolated to humans.« less

Passive micromixer using by convection and surface tension effects with air-liquid interface.

PubMed

Ju, Jongil; Warrick, Jay

2013-12-01

This article describes a passive micromixer that utilizes an air-liquid interface and surface tension effects to enhance fluid mixing via convection and Marangoni effects. Performance of the microfluidic component is tested within a passive-pumping-based device that consists of three microchannels connected in succession using passive micro-mixers. Mixing was quantified at 5 key points along the length of the device using microscope images of patterned streams of Alexa 488 fluorescent-dyed water and pure DI water flowing through the device. The passive micro-mixer mixed fluid 15-20 times more effectively than diffusion between laminar flow streams alone and is a novel micro-mixer embodiment that provides an additional strategy for removing external components from microscale devices for simpler, autonomous operation.

Passive micromixer using by convection and surface tension effects with air-liquid interface

PubMed Central

Ju, Jongil; Warrick, Jay

2014-01-01

This article describes a passive micromixer that utilizes an air-liquid interface and surface tension effects to enhance fluid mixing via convection and Marangoni effects. Performance of the microfluidic component is tested within a passive-pumping-based device that consists of three microchannels connected in succession using passive micro-mixers. Mixing was quantified at 5 key points along the length of the device using microscope images of patterned streams of Alexa 488 fluorescent-dyed water and pure DI water flowing through the device. The passive micro-mixer mixed fluid 15–20 times more effectively than diffusion between laminar flow streams alone and is a novel micro-mixer embodiment that provides an additional strategy for removing external components from microscale devices for simpler, autonomous operation. PMID:25104979

Influence of La addition on the semi-conductive properties of passive films formed on Cu-Ni alloy

NASA Astrophysics Data System (ADS)

Leng, Xiang; Zhang, Yadong; Zhou, Qiongyu; Zhang, Yinghui; Wang, Zhigang; Wang, Hang; Yang, Bin

2018-05-01

The semi-conductive properties of passive films formed on Cu-Ni alloy and Cu-Ni-La alloy were investigated in 0.1 M NaOH solution, by employing electrochemical impedance spectroscopy (EIS), Mott–Schottky analysis and point defect model (PDM). Results indicate that both the passive films formed on Cu-Ni alloy and Cu-Ni-La alloy display p-type semi-conductive characteristics with cation vacancies in order of magnitude of 1020 cm3. Compared with Cu-Ni alloy, La addition could significantly improve the corrosion resistance, due to a superior barrier passive film formed Cu-Ni-La alloy with a bigger film resistance (R f), increased passive film thickness (L ss) in conjunction with decreased diffusion coefficient (D 0).

Passivity of Directed and Undirected Complex Dynamical Networks With Adaptive Coupling Weights.

PubMed

Wang, Jin-Liang; Wu, Huai-Ning; Huang, Tingwen; Ren, Shun-Yan; Wu, Jigang

2017-08-01

A complex dynamical network consisting of N identical neural networks with reaction-diffusion terms is considered in this paper. First, several passivity definitions for the systems with different dimensions of input and output are given. By utilizing some inequality techniques, several criteria are presented, ensuring the passivity of the complex dynamical network under the designed adaptive law. Then, we discuss the relationship between the synchronization and output strict passivity of the proposed network model. Furthermore, these results are extended to the case when the topological structure of the network is undirected. Finally, two examples with numerical simulations are provided to illustrate the correctness and effectiveness of the proposed results.

Spectral Analysis and Computation of Effective Diffusivities for Steady Random Flows

DTIC Science & Technology

2016-04-28

even in the motion of sea ice floes influenced by winds and ocean currents. The long time, large scale behavior of such systems is equivalent to an...flow plays a key role in many important processes in the global climate system [55] and Earth’s ecosys- tems [14]. Advection of geophysical fluids...HOMOGENIZATION OF THE ADVECTION-DIFFUSION EQUATION The dispersion of a cloud of passive scalars with density φ diffusing with molecular dif- fusivity ε and

Passive sampling of DDT, DDE and DDD in sediments: accounting for degradation processes with reaction-diffusion modeling.

PubMed

Tcaciuc, A Patricia; Borrelli, Raffaella; Zaninetta, Luciano M; Gschwend, Philip M

2018-01-24

Passive sampling is becoming a widely used tool for assessing freely dissolved concentrations of hydrophobic organic contaminants in environmental media. For certain media and target analytes, the time to reach equilibrium exceeds the deployment time, and in such cases, the loss of performance reference compounds (PRCs), loaded in the sampler before deployment, is one of the common ways used to assess the fractional equilibration of target analytes. The key assumption behind the use of PRCs is that their release is solely diffusion driven. But in this work, we show that PRC transformations in the sediment can have a measurable impact on the PRC releases and even allow estimation of that compound's transformation rate in the environment of interest. We found that in both field and lab incubations, the loss of the 13 C 2,4'-DDT PRC from a polyethylene (PE) passive sampler deployed at the sediment-water interface was accelerated compared to the loss of other PRCs ( 13 C-labeled PCBs, 13 C-labeled DDE and DDD). The DDT PRC loss was also accompanied by accumulation in the PE of its degradation product, 13 C 2,4'-DDD. Using a 1D reaction-diffusion model, we deduced the in situ degradation rates of DDT from the measured PRC loss. The in situ degradation rates increased with depth into the sediment bed (0.14 d -1 at 0-10 cm and 1.4 d -1 at 30-40 cm) and although they could not be independently validated, these rates compared favorably with literature values. This work shows that passive sampling users should be cautious when choosing PRCs, as degradation processes can affect some PRC's releases from the passive sampler. More importantly, this work opens up the opportunity for novel applications of passive samplers, particularly with regard to investigating in situ degradation rates, pathways, and products for both legacy and emerging contaminants. However, further work is needed to confirm that the rates deduced from model fitting of PRC loss are a true reflection of DDT transformation rates in sediments.

Numerically exploring habitat fragmentation effects on populations using cell-based coupled map lattices

Treesearch

Michael Bevers; Curtis H. Flather

1999-01-01

We examine habitat size, shape, and arrangement effects on populations using a discrete reaction-diffusion model. Diffusion is modeled passively and applied to a cellular grid of territories forming a coupled map lattice. Dispersal mortality is proportional to the amount of nonhabitat and fully occupied habitat surrounding a given cell, with distance decay. After...

Simultaneous Analysis of 22 Volatile Organic Compounds in Cigarette Smoke Using Gas Sampling Bags for High-Throughput Solid-Phase Microextraction

PubMed Central

Sampson, Maureen M.; Chambers, David M.; Pazo, Daniel Y.; Moliere, Fallon; Blount, Benjamin C.; Watson, Clifford H.

2015-01-01

Quantifying volatile organic compounds (VOCs) in cigarette smoke is necessary to establish smoke-related exposure estimates and evaluate emerging products and potential reduced-exposure products. In response to this need, we developed an automated, multi-VOC quantification method for machine-generated, mainstream cigarette smoke using solidphase microextraction gas chromatography–mass spectrometry (SPME-GC–MS). This method was developed to simultaneously quantify a broad range of smoke VOCs (i.e., carbonyls and volatiles, which historically have been measured by separate assays) for large exposure assessment studies. Our approach collects and maintains vapor-phase smoke in a gas sampling bag, where it is homogenized with isotopically labeled analogue internal standards and sampled using gas-phase SPME. High throughput is achieved by SPME automation using a CTC Analytics platform and custom bag tray. This method has successfully quantified 22 structurally diverse VOCs (e.g., benzene and associated monoaromatics, aldehydes and ketones, furans, acrylonitrile, 1,3-butadiene, vinyl chloride, and nitromethane) in the microgram range in mainstream smoke from 1R5F and 3R4F research cigarettes smoked under ISO (Cambridge Filter or FTC) and Intense (Health Canada or Canadian Intense) conditions. Our results are comparable to previous studies with few exceptions. Method accuracy was evaluated with third-party reference samples (≤15% error). Short-term diffusion losses from the gas sampling bag were minimal, with a 10% decrease in absolute response after 24 h. For most analytes, research cigarette inter- and intrarun precisions were ≤20% relative standard deviation (RSD). This method provides an accurate and robust means to quantify VOCs in cigarette smoke spanning a range of yields that is sufficient to characterize smoke exposure estimates. PMID:24933649

Modeling of molecular diffusion and thermal conduction with multi-particle interaction in compressible turbulence

NASA Astrophysics Data System (ADS)

Tai, Y.; Watanabe, T.; Nagata, K.

2018-03-01

A mixing volume model (MVM) originally proposed for molecular diffusion in incompressible flows is extended as a model for molecular diffusion and thermal conduction in compressible turbulence. The model, established for implementation in Lagrangian simulations, is based on the interactions among spatially distributed notional particles within a finite volume. The MVM is tested with the direct numerical simulation of compressible planar jets with the jet Mach number ranging from 0.6 to 2.6. The MVM well predicts molecular diffusion and thermal conduction for a wide range of the size of mixing volume and the number of mixing particles. In the transitional region of the jet, where the scalar field exhibits a sharp jump at the edge of the shear layer, a smaller mixing volume is required for an accurate prediction of mean effects of molecular diffusion. The mixing time scale in the model is defined as the time scale of diffusive effects at a length scale of the mixing volume. The mixing time scale is well correlated for passive scalar and temperature. Probability density functions of the mixing time scale are similar for molecular diffusion and thermal conduction when the mixing volume is larger than a dissipative scale because the mixing time scale at small scales is easily affected by different distributions of intermittent small-scale structures between passive scalar and temperature. The MVM with an assumption of equal mixing time scales for molecular diffusion and thermal conduction is useful in the modeling of the thermal conduction when the modeling of the dissipation rate of temperature fluctuations is difficult.

Passive Imaging in Nondiffuse Acoustic Wavefields

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

Mulargia, Francesco; Castellaro, Silvia

2008-05-30

A main property of diffuse acoustic wavefields is that, taken any two points, each of them can be seen as the source of waves and the other as the recording station. This property is shown to follow simply from array azimuthal selectivity and Huygens principle in a locally isotropic wavefield. Without time reversal, this property holds approximately also in anisotropic azimuthally uniform wavefields, implying much looser constraints for undistorted passive imaging than those required by a diffuse field. A notable example is the seismic noise field, which is generally nondiffuse, but is found to be compatible with a finite aperturemore » anisotropic uniform wavefield. The theoretical predictions were confirmed by an experiment on seismic noise in the mainland of Venice, Italy.« less

The role of halide ions on the electrochemical behaviour of iron in alkali solutions

NASA Astrophysics Data System (ADS)

Begum, S. Nathira; Muralidharan, V. S.; Basha, C. Ahmed

2008-02-01

Active dissolution and passivation of transition metals in alkali solutions is of technological importance in batteries. The performance of alkaline batteries is decided by the presence of halides as they influence passivation. Cyclic voltammetric studies were carried out on iron in different sodium hydroxide solutions in presence of halides. In alkali solutions iron formed hydroxo complexes and their polymers in the interfacial diffusion layer. With progress of time they formed a cation selective layer. The diffusion layer turned into bipolar ion selective layer consisted of halides, a selective inner sublayer to the metal side and cation selective outer layer to the solution side. At very high anodic potentials, dehydration and deprotonation led to the conversion of salt layer into an oxide.

Development of a model using the MATLAB System identification toolbox to estimate (222)Rn equilibrium factor from CR-39 based passive measurements.

PubMed

Abo-Elmagd, M; Sadek, A M

2014-12-01

Can and Bare method is a widely used passive method for measuring the equilibrium factor F through the determination of the track density ratio between bare (D) and filtered (Do) detectors. The dimensions of the used diffusion chamber are altering the deposition ratios of Po-isotopes on the chamber walls as well as the ratios of the existing alpha emitters in air. Then the measured filtered track density and therefore the resultant equilibrium factor is changed according to the diffusion chamber dimensions. For this reason, high uncertainty was expected in the measured F using different diffusion chambers. In the present work, F is derived as a function of both track density ratio (D/Do) and the dimensions of the used diffusion chambers (its volume to the total internal surface area; V/A). The accuracy of the derived formula was verified using the black-box modeling technique via the MATLAB System identification toolbox. The results show that the uncertainty of the calculated F by using the derived formula of F (D/Do, V/A) is only 5%. The obtained uncertainty ensures the quality of the derived function to calculate F using diffusion chambers with wide range of dimensions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Demonstration and Validation of a Regenerated Cellulose Dialysis Membrane Diffusion Sampler for Monitoring Ground-Water Quality and Remediation Progress at DoD Sites

DTIC Science & Technology

2010-04-01

LDPE low-density polyethylene LF low-flow purging LRL laboratory reporting level MDL minimum detection limit MNA monitored natural attenuation...shaped bag made of flexible low-density polyethylene ( LDPE ) (Vroblesky, 2001a, 2001b). The LDPE tube is heat-sealed on one end, filled with high...from small- diameter LDPE tubing that fits into small-diameter wells. These PDB samplers have been shown to be useful only for collection of VOCs

Potential of pedestrian protection systems--a parameter study using finite element models of pedestrian dummy and generic passenger vehicles.

PubMed

Fredriksson, Rikard; Shin, Jaeho; Untaroiu, Costin D

2011-08-01

To study the potential of active, passive, and integrated (combined active and passive) safety systems in reducing pedestrian upper body loading in typical impact configurations. Finite element simulations using models of generic sedan car fronts and the Polar II pedestrian dummy were performed for 3 impact configurations at 2 impact speeds. Chest contact force, head injury criterion (HIC(15)), head angular acceleration, and the cumulative strain damage measure (CSDM(0.25)) were employed as injury parameters. Further, 3 countermeasures were modeled: an active autonomous braking system, a passive deployable countermeasure, and an integrated system combining the active and passive systems. The auto-brake system was modeled by reducing impact speed by 10 km/h (equivalent to ideal full braking over 0.3 s) and introducing a pitch of 1 degree and in-crash deceleration of 1 g. The deployable system consisted of a deployable hood, lifting 100 mm in the rear, and a lower windshield air bag. All 3 countermeasures showed benefit in a majority of impact configurations in terms of injury prevention. The auto-brake system reduced chest force in a majority of the configurations and decreased HIC(15), head angular acceleration, and CSDM in all configurations. Averaging all impact configurations, the auto-brake system showed reductions of injury predictors from 20 percent (chest force) to 82 percent (HIC). The passive deployable countermeasure reduced chest force and HIC(15) in a majority of configurations and head angular acceleration and CSDM in all configurations, although the CSDM decrease in 2 configurations was minimal. On average a reduction from 20 percent (CSDM) to 58 percent (HIC) was recorded in the passive deployable countermeasures. Finally, the integrated system evaluated in this study reduced all injury assessment parameters in all configurations compared to the reference situations. The average reductions achieved by the integrated system ranged from 56 percent (CSDM) to 85 percent (HIC). Both the active (autonomous braking) and passive deployable system studied had a potential to decrease pedestrian upper body loading. An integrated pedestrian safety system combining the active and passive systems increased the potential of the individual systems in reducing pedestrian head and chest loading.

In situ application of a cellulose bag and an ion exchanger for differentiation of labile and inert metal species in aquatic systems.

PubMed

Goveia, Danielle; Rosa, André Henrique; Bellin, Iramaia Corrêa; Lobo, Fabiana Aparecida; Fraceto, Leonardo Fernandes; Roveda, José Arnaldo Frutuoso; Romão, Luciane Pimenta Cruz; Dias Filho, Newton Luiz

2008-02-01

This work involved the development and application of a new analytical procedure for in-situ characterization of the lability of metal species in aquatic systems by using a system equipped with a diffusion membrane and cellulose organomodified with p-aminobenzoic acid groups (DM-Cell-PAB). To this end, the DM-Cell-PAB system was prepared by adding cellulose organomodified with p-aminobenzoic acid groups (Cell-PAB) to pre-purified cellulose bags. After the DM-Cell-PAB system was sealed, it was examined in the laboratory. The in-situ application involved immersing the DM-Cell-PAB system in two different rivers, enabling us to study the relative lability of metal species (Cu, Cd, Fe, Mn, and Ni) as a function of time and quantity of exchanger. The procedure is simple and opens up a new perspective for understanding environmental phenomena relating to the complexation, transport, stability, and lability of metal species in aquatic systems rich in organic matter.

Enhancement of diffusive transport in oscillatory flows

NASA Technical Reports Server (NTRS)

Knobloch, E.; Merryfield, W. J.

1992-01-01

The theory of transport of passive scalars in oscillatory flows is reexamined. The differences between transport in standing and traveling waves are emphasized. Both Lagrangian and Eulerian diffusivities are calculated, and the conditions for their applicability are discussed. Numerical simulations are conducted to understand the expulsion of gradients from time-dependent eddies and the resulting transport. The results indicate that it is the Eulerian diffusivity that is of primary relevance for describing enhanced transport on spatial scales larger than that of the eddies.

Nitridation of SiO2 for surface passivation

NASA Technical Reports Server (NTRS)

Lai, S. K. C.

1985-01-01

An attempt is made to relate the electrical properties of silicon dioxide film to the process history. A model is proposed to explain some of the observed results. It is shown that with our present knowledge of the dielectric, silicon dioxide film shows a lot of promise for its use in surface passivation, both for its resistance to impurity diffusion and for its resistance to radiation damage effects.

It's in the Bag!

ERIC Educational Resources Information Center

Renfro, Nancy

1983-01-01

Thirteen ideas for using paper bags for class art activities are given. Directions for making bag barracudas, bionic bags, bigfoot bags, bag sculptures, bag beads, and body bag superstars are included. (PP)

Extracting dielectric fixed charge density on highly doped crystalline-silicon surfaces using photoconductance measurements

NASA Astrophysics Data System (ADS)

To, A.; Hoex, B.

2017-11-01

A novel method for the extraction of fixed interface charge, Qf, and the surface recombination parameters, Sn0 and Sp0, from the injection-level dependent effective minority carrier lifetime measurements is presented. Unlike conventional capacitance-voltage measurements, this technique can be applied to highly doped surfaces provided the surface carrier concentration transitions into strong depletion or inversion with increased carrier injection. By simulating the injection level dependent Auger-corrected inverse lifetime curve of symmetrically passivated and diffused samples after sequential annealing and corona charging, it was revealed that Qf, Sn0, and Sp0 have unique signatures. Therefore, these important electronic parameters, in some instances, can independently be resolved. Furthermore, it was shown that this non-linear lifetime behaviour is exhibited on both p-type and n-type diffused inverted surfaces, by demonstrating the approach with phosphorous diffused n+pn+ structures and boron diffused p+np+ structures passivated with aluminium oxide (AlOx) and silicon nitride, respectively (SiNx). The results show that the approximation of a mid-gap Shockley-Read-Hall defect level with equal capture cross sections is able to, in the samples studied in this work, reproduce the observed injection level dependent lifetime behaviour.

CdCl2 passivation of polycrystalline CdMgTe and CdZnTe absorbers for tandem photovoltaic cells

NASA Astrophysics Data System (ADS)

Swanson, Drew E.; Reich, Carey; Abbas, Ali; Shimpi, Tushar; Liu, Hanxiao; Ponce, Fernando A.; Walls, John M.; Zhang, Yong-Hang; Metzger, Wyatt K.; Sampath, W. S.; Holman, Zachary C.

2018-05-01

As single-junction silicon solar cells approach their theoretical limits, tandems provide the primary path to higher efficiencies. CdTe alloys can be tuned with magnesium (CdMgTe) or zinc (CdZnTe) for ideal tandem pairing with silicon. A II-VI/Si tandem holds the greatest promise for inexpensive, high-efficiency top cells that can be quickly deployed in the market using existing polycrystalline CdTe manufacturing lines combined with mature silicon production lines. Currently, all high efficiency polycrystalline CdTe cells require a chloride-based passivation process to passivate grain boundaries and bulk defects. This research examines the rich chemistry and physics that has historically limited performance when extending Cl treatments to polycrystalline 1.7-eV CdMgTe and CdZnTe absorbers. A combination of transmittance, quantum efficiency, photoluminescence, transmission electron microscopy, and energy-dispersive X-ray spectroscopy clearly reveals that during passivation, Mg segregates and out-diffuses, initially at the grain boundaries but eventually throughout the bulk. CdZnTe exhibits similar Zn segregation behavior; however, the onset and progression is localized to the back of the device. After passivation, CdMgTe and CdZnTe can render a layer that is reduced to predominantly CdTe electro-optical behavior. Contact instabilities caused by inter-diffusion between the layers create additional complications. The results outline critical issues and paths for these materials to be successfully implemented in Si-based tandems and other applications.

Performances and application of a passive sampling method for the simultaneous determination of nitrogen dioxide and sulfur dioxide in ambient air.

PubMed

Plaisance, H; Sagnier, I; Saison, J Y; Galloo, J C; Guillermo, R

2002-11-01

The performances and applicability of a diffusion tube sampler for the simultaneous measurements of NO2 and SO2 in ambient air were evaluated. SO2 and NO2 are collected by the passive sampler using triethanolamine as trapping agent and are determined as sulphate and nitrite with ion chromatography. The detection limit (2.3 microg m(-3) of NO2 and 4.2 microg m(-3) of SO2 for two weeks sampling) is adequate for the determination of concentrations in urban and industrial areas. Precision of the method as RSD is in mean 5% for NO2 and 12% for SO2 at the concentration levels in urban areas. Calibration of the method was performed in the field conditions by comparison between the responses of sampler and the concentrations measured by the continuous monitors. High degree of linearity (correlation coefficients > 0.8) is found between the passive sampler tube and the continuous monitor data for both NO2 and SO2. To reduce the wind velocity influence on passive sampling of diffusion tubes, a protective shelter was tested in this study. The overall uncertainty of one measure for the optimised method is estimated at 5 microg m(-3) for NO2 and 6 microg m(-3) for SO2. Suitability of this passive sampling method for air pollution monitoring in urban areas was demonstrated by the results shown in this paper on a campaign carried out in the French agglomeration.

Comparative Measurements of Radon Concentration in Soil Using Passive and Active Methods in High Level Natural Radiation Area (HLNRA) of Ramsar

PubMed Central

Amanat, B; Kardan, M R; Faghihi, R; Hosseini Pooya, S M

2013-01-01

Background: Radon and its daughters are amongst the most important sources of natural exposure in the world. Soil is one of the significant sources of radon/thoron due to both radium and thorium so that the emanated thoron from it may cause increased uncertainties in radon measurements. Recently, a diffusion chamber has been designed and optimized for passive discriminative measurements of radon/thoron concentrations in soil. Objective: In order to evaluate the capability of the passive method, some comparative measurements (with active methods) have been performed. Method: The method is based upon measurements by a diffusion chamber, including two Lexan polycarbonate SSNTDs, which can discriminate the emanated radon/thorn from the soil by delay method. The comparative measurements have been done in ten selected points of HLNRA of Ramsar in Iran. The linear regression and correlation between the results of two methods have been studied. Results: The results show that the radon concentrations are within the range of 12.1 to 165 kBq/m3 values. The correlation between the results of active and passive methods was measured by 0.99 value. As well, the thoron concentrations have been measured between 1.9 to 29.5 kBq/m3 values at the points. Conclusion: The sensitivity as well as the strong correlation with active measurements shows that the new low-cost passive method is appropriate for accurate seasonal measurements of radon and thoron concentration in soil. PMID:25505760

Passivation of c-Si surfaces by sub-nm amorphous silicon capped with silicon nitride

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

Wan, Yimao, E-mail: yimao.wan@anu.edu.au; Yan, Di; Bullock, James

2015-12-07

A sub-nm hydrogenated amorphous silicon (a-Si:H) film capped with silicon nitride (SiN{sub x}) is shown to provide a high level passivation to crystalline silicon (c-Si) surfaces. When passivated by a 0.8 nm a-Si:H/75 nm SiN{sub x} stack, recombination current density J{sub 0} values of 9, 11, 47, and 87 fA/cm{sup 2} are obtained on 10 Ω·cm n-type, 0.8 Ω·cm p-type, 160 Ω/sq phosphorus-diffused, and 120 Ω/sq boron-diffused silicon surfaces, respectively. The J{sub 0} on n-type 10 Ω·cm wafers is further reduced to 2.5 ± 0.5 fA/cm{sup 2} when the a-Si:H film thickness exceeds 2.5 nm. The passivation by the sub-nm a-Si:H/SiN{sub x} stack is thermally stable at 400 °C in N{sub 2} formore » 60 min on all four c-Si surfaces. Capacitance–voltage measurements reveal a reduction in interface defect density and film charge density with an increase in a-Si:H thickness. The nearly transparent sub-nm a-Si:H/SiN{sub x} stack is thus demonstrated to be a promising surface passivation and antireflection coating suitable for all types of surfaces encountered in high efficiency c-Si solar cells.« less

Modeling the transport of organic chemicals between polyethylene passive samplers and water in finite and infinite bath conditions.

PubMed

Tcaciuc, A Patricia; Apell, Jennifer N; Gschwend, Philip M

2015-12-01

Understanding the transfer of chemicals between passive samplers and water is essential for their use as monitoring devices of organic contaminants in surface waters. By applying Fick's second law to diffusion through the polymer and an aqueous boundary layer, the authors derived a mathematical model for the uptake of chemicals into a passive sampler from water, in finite and infinite bath conditions. The finite bath model performed well when applied to laboratory observations of sorption into polyethylene (PE) sheets for various chemicals (polycyclic aromatic hydrocarbons, polychlorinated biphenyls [PCBs], and dichlorodiphenyltrichloroethane [DDT]) and at varying turbulence levels. The authors used the infinite bath model to infer fractional equilibration of PCB and DDT analytes in field-deployed PE, and the results were nearly identical to those obtained using the sampling rate model. However, further comparison of the model and the sampling rate model revealed that the exchange of chemicals was inconsistent with the sampling rate model for partially or fully membrane-controlled transfer, which would be expected in turbulent conditions or when targeting compounds with small polymer diffusivities and small partition coefficients (e.g., phenols, some pesticides, and others). The model can be applied to other polymers besides PE as well as other chemicals and in any transfer regime (membrane, mixed, or water boundary layer-controlled). Lastly, the authors illustrate practical applications of this model such as improving passive sampler design and understanding the kinetics of passive dosing experiments. © 2015 SETAC.

Absorption of resveratrol by vascular endothelial cells through passive diffusion and an SGLT1-mediated pathway.

PubMed

Chen, Ming-liang; Yi, Long; Jin, Xin; Xie, Qi; Zhang, Ting; Zhou, Xi; Chang, Hui; Fu, Yu-jie; Zhu, Jun-dong; Zhang, Qian-yong; Mi, Man-tian

2013-11-01

Resveratrol is a natural polyphenol that exerts potent effects to suppress atherosclerosis. However, its low concentration in plasma has placed this role in doubt. Thus, resveratrol effects might be dependent on its transport into vascular endothelium, a question not previously addressed in spite of its obvious and fundamental importance. Via high-performance liquid chromatography and liquid chromatography/mass spectrometry, we found that resveratrol was absorbed by human umbilical vein endothelial cells in a temperature-, concentration- and time-dependent manner, suggesting the involvement of passive diffusion and active transport. As determined by confocal laser scanning microscopy, resveratrol primarily distributed throughout the cytoplasm. Furthermore, resveratrol absorption was modulated by serum proteins and sodium-dependent glucose transporter 1 (SGLT1) yet inhibited by glucose (an SGLT1 substrate) and phlorizin (an SGLT1 selective inhibitor), as well as SGLT1 siRNA transfection. Additionally, Sprague-Dawley rats were intragastrically administrated with 100mg/kg of resveratrol and the concentration of resveratrol in blood vessels declined more slowly up to 24h compared to that in the blood. Our results suggested that resveratrol uptake by vascular endothelial cells involved both passive diffusion and an SGLT1-mediated process, at least partially. Moreover, the intracellular resveratrol pool may be more important than the serum level in vivo. These provide new insights into the cardiovascular benefits of resveratrol. Copyright © 2013 Elsevier Inc. All rights reserved.

Bag-of-features approach for improvement of lung tissue classification in diffuse lung disease

NASA Astrophysics Data System (ADS)

Kato, Noriji; Fukui, Motofumi; Isozaki, Takashi

2009-02-01

Many automated techniques have been proposed to classify diffuse lung disease patterns. Most of the techniques utilize texture analysis approaches with second and higher order statistics, and show successful classification result among various lung tissue patterns. However, the approaches do not work well for the patterns with inhomogeneous texture distribution within a region of interest (ROI), such as reticular and honeycombing patterns, because the statistics can only capture averaged feature over the ROI. In this work, we have introduced the bag-of-features approach to overcome this difficulty. In the approach, texture images are represented as histograms or distributions of a few basic primitives, which are obtained by clustering local image features. The intensity descriptor and the Scale Invariant Feature Transformation (SIFT) descriptor are utilized to extract the local features, which have significant discriminatory power due to their specificity to a particular image class. In contrast, the drawback of the local features is lack of invariance under translation and rotation. We improved the invariance by sampling many local regions so that the distribution of the local features is unchanged. We evaluated the performance of our system in the classification task with 5 image classes (ground glass, reticular, honeycombing, emphysema, and normal) using 1109 ROIs from 211 patients. Our system achieved high classification accuracy of 92.8%, which is superior to that of the conventional system with the gray level co-occurrence matrix (GLCM) feature especially for inhomogeneous texture patterns.

Determination of deployment specific chemical uptake rates for SDB-RPD Empore disk using a passive flow monitor (PFM).

PubMed

O'Brien, Dominique; Bartkow, Michael; Mueller, Jochen F

2011-05-01

The use of the adsorbent styrenedivinylbenzene-reverse phase sulfonated (SDB-RPD) Empore disk in a chemcatcher type passive sampler is routinely applied in Australia when monitoring herbicides in aquatic environments. One key challenge in the use of passive samplers is mitigating the potentially confounding effects of varying flow conditions on chemical uptake by the passive sampler. Performance reference compounds (PRCs) may be applied to correct sampling rates (R(s)) for site specific changed in flow and temperature however evidence suggests the use of PRCs is unreliable when applied to adsorbent passive samplers. The use of the passive flow monitor (PFM) has been introduced for the assessment of site-specific changes in water flow. In the presented study we have demonstrated that the R(s) at which both atrazine and prometryn are accumulated within the SDB-RPD-Empore disk is dependent on the flow conditions. Further, the calibration of the measured R(s) for chemical uptake by the SDB-RPD-Empore disk to the mass lost from the PFM has shown that the PFM provides an accurate measure of R(s) for flow velocities from 0 to 16cms(-1). Notably, for flow rates >16cms(-1), a non linear increase in the R(s) of both herbicides was observed which indicates that the key resistance to uptake into the SDB-RPD Empore disk is associated with the diffusion through the overlying diffusion limiting membrane. Overall the greatest uncertainty remains at very low flow conditions, which are unlikely to often occur in surface waters. Validation of the PFM use has also been undertaken in a limited field study. Copyright © 2011 Elsevier Ltd. All rights reserved.

Fluorescent recovery after photobleaching (FRAP) analysis of nuclear export rates identifies intrinsic features of nucleocytoplasmic transport.

PubMed

Cardarelli, Francesco; Tosti, Luca; Serresi, Michela; Beltram, Fabio; Bizzarri, Ranieri

2012-02-17

A quantitative description of carrier-mediated nuclear export in live cells is presented. To this end, we fused a prototypical leucine-rich nuclear export signal (NES) to GFP as a cargo model and expressed the fluorescent chimera in live CHO-K1 cells. By modeling FRAP data, we calculate the NES affinity for the export machinery and the maximum rate of nuclear export achievable at saturation of endogenous carriers. The measured active-export time through the Nuclear Pore Complex (NPC) is 18 ms, remarkably similar to the previously determined active-import rate. Also, our results reveal that active export/import and active export/passive diffusion fluxes are uncoupled, thus complementing previous reports on active import/passive diffusion uncoupling. These findings suggest differential gating at the NPC level.

Managing evaporation for more robust microscale assays. Part 2. Characterization of convection and diffusion for cell biology.

PubMed

Berthier, Erwin; Warrick, Jay; Yu, Hongmeiy; Beebe, David J

2008-06-01

Cell based microassays allow the screening of a multitude of culture conditions in parallel, which can be used for various applications from drug screening to fundamental cell biology research. Tubeless microfluidic devices based on passive pumping are a step towards accessible high throughput microassays, however they are vulnerable to evaporation. In addition to volume loss, evaporation can lead to the generation of small flows. Here, we focus on issues of convection and diffusion for cell culture in microchannels and particularly the transport of soluble factors secreted by cells. We find that even for humidity levels as high as 95%, convection in a passive pumping channel can significantly alter distributions of these factors and that appropriate system design can prevent convection.

Isotopic fractionation of volatile species during bubble growth in magmas

NASA Astrophysics Data System (ADS)

Watson, E. B.

2016-12-01

Bubbles grow in decompressing magmas by simple expansion and also by diffusive supply of volatiles to the bubble/melt interface. The latter phenomenon is of significant geochemical interest because diffusion can fractionate isotopes, raising the possibility that the isotopic character of volatile components in bubbles may not reflect that of volatiles dissolved in the host melt over the lifetime of a bubble—even in the complete absence of equilibrium vapor/melt isotopic fractionation. None of the foregoing is conceptually new, but recent experimental studies have established the existence of isotope mass effects on diffusion in silicate melts for several elements (Li, Mg, Ca, Fe), and this finding has now been extended to the volatile (anionic) element chlorine (Fortin et al. 2016; this meeting). Knowledge of isotope mass effects on diffusion of volatile species opens the way for quantitative models of diffusive fractionation during bubble growth. Significantly different effects are anticipated for "passive" volatiles (e.g., noble gases and Cl) that are partitioned into existing bubbles but play little role in nucleation and growth, as opposed to "active" volatiles whose limited solubilities lead to bubble nucleation during magma decompression. Numerical solution of the appropriate diffusion/mass-conservation equations reveals that the isotope effect on passive volatiles partitioned into bubbles growing at a constant rate in a static system depends (predictably) upon R/D, Kd and D1/D2 (R = growth rate; D = diffusivity; Kd = bubble/melt partition coefficient; D1/D2 = diffusivity ratio of the isotopes of interest). Constant R is unrealistic, but other scenarios can be explored by including the solubility and EOS of an "active" volatile (e.g., CO2) in numerical simulations of bubble growth. For plausible decompression paths, R increases exponentially with time—leading, potentially, to larger isotopic fractionation of species partitioned into the growing bubble.

Corrosion Properties of Dissimilar Friction Stir Welded 6061 Aluminum and HT590 Steel

NASA Astrophysics Data System (ADS)

Seo, Bosung; Song, Kuk Hyun; Park, Kwangsuk

2018-05-01

Corrosion properties of dissimilar friction stir welded 6061 aluminum and HT590 steel were investigated to understand effects of galvanic corrosion. As cathode when coupled, HT590 was cathodically protected. However, the passivation of AA6061 made the aluminum alloy cathode temporarily, which leaded to corrosion of HT590. From the EIS analysis showing Warburg diffusion plot in Nyquist plots, it can be inferred that the stable passivation layer was formed on AA6061. However, the weld as well as HT590 did not show Warburg diffusion plot in Nyquist plots, suggesting that there was no barrier for corrosion or even if it exists, the barrier had no function for preventing and/or retarding charge transport through the passivation layer. The open circuit potential measurements showed that the potential of the weld was similar to that of HT590, which lied in the pitting region for AA6061, making the aluminum alloy part of the weld keep corrosion state. That resulted in the cracked oxide film on AA6061 of the weld, which could not play a role of corrosion barrier.

Diffusion tensor imaging reveals changes in the adult rat brain following long-term and passive moderate acoustic exposure.

PubMed

Abdoli, Sherwin; Ho, Leon C; Zhang, Jevin W; Dong, Celia M; Lau, Condon; Wu, Ed X

2016-12-01

This study investigated neuroanatomical changes following long-term acoustic exposure at moderate sound pressure level (SPL) under passive conditions, without coupled behavioral training. The authors utilized diffusion tensor imaging (DTI) to detect morphological changes in white matter. DTIs from adult rats (n = 8) exposed to continuous acoustic exposure at moderate SPL for 2 months were compared with DTIs from rats (n = 8) reared under standard acoustic conditions. Two distinct forms of DTI analysis were applied in a sequential manner. First, DTI images were analyzed using voxel-based statistics which revealed greater fractional anisotropy (FA) of the pyramidal tract and decreased FA of the tectospinal tract and trigeminothalamic tract of the exposed rats. Region of interest analysis confirmed (p < 0.05) that FA had increased in the pyramidal tract but did not show a statistically significant difference in the FA of the tectospinal or trigeminothalamic tract. The results of the authors show that long-term and passive acoustic exposure at moderate SPL increases the organization of white matter in the pyramidal tract.

Wilson Corners SWMU 001 2014 Annual Long Term Monitoring Report Kennedy Space Center, Florida

NASA Technical Reports Server (NTRS)

Langenbach, James

2015-01-01

This document presents the findings of the 2014 Long Term Monitoring (LTM) that was completed at the Wilson Corners site, located at the National Aeronautics and Space Administration (NASA) John F. Kennedy Space Center (KSC), Florida. The goals of the 2014 annual LTM event were to evaluate the groundwater flow direction and gradient and to monitor the vertical and downgradient horizontal extent of the volatile organic compounds (VOCs) in groundwater at the site. The LTM activities consisted of an annual groundwater sampling event in December 2014, which included the collection of water levels from the LTM wells. During the annual groundwater sampling event, depth to groundwater was measured and VOC samples were collected using passive diffusion bags (PDBs) from 30 monitoring wells. In addition to the LTM sampling, additional assessment sampling was performed at the site using low-flow techniques based on previous LTM results and assessment activities. Assessment of monitoring well MW0052DD was performed by collecting VOC samples using low-flow techniques before and after purging 100 gallons from the well. Monitoring well MW0064 was sampled to supplement shallow VOC data north of Hot Spot 2 and east of Hot Spot 4. Monitoring well MW0089 was sampled due to its proximity to MW0090. MW0090 is screened in a deeper interval and had an unexpected detection of trichloroethene (TCE) during the 2013 LTM, which was corroborated during the March 2014 verification sampling. Monitoring well MW0130 was sampled to provide additional VOC data beneath the semi-confining clay layer in the Hot Spot 2 area.

Diffusive Insights: On the Disagreement of Christian Bohr and August Krogh at the Centennial of the Seven Little Devils

ERIC Educational Resources Information Center

Gjedde, Albert

2010-01-01

The year 2010 is the centennial of the publication of the "Seven Little Devils" in the predecessor of "Acta Physiologica". In these seven papers, August and Marie Krogh sought to refute Christian Bohr's theory that oxygen diffusion from the lungs to the circulation is not entirely passive but rather facilitated by a specific cellular activity…

A study of the feasibility and performance of an active/passive imager using silicon focal plane arrays and incoherent continuous wave laser diodes

NASA Astrophysics Data System (ADS)

Vollmerhausen, Richard H.

This dissertation describes an active/passive imager (API) that provides reliable, nighttime, target acquisition in a man-portable package with effective visual range of about 4 kilometers. The reflective imagery is easier to interpret than currently used thermal imagery. Also, in the active mode, the API provides performance equivalent to the big-aperture, thermal systems used on weapons platforms like tanks and attack helicopters. This dissertation describes the research needed to demonstrate both the feasibility and utility of the API. Part of the research describes implementation of a silicon focal plane array (SFPA) capable of both active and passive imaging. The passive imaging mode exceeds the nighttime performance of currently fielded, man-portable sensors. Further, when scene illumination is insufficient for passive imaging, the low dark current of SFPA makes it possible to use continuous wave laser diodes (CWLD) to add an active imaging mode. CWLD have advantages of size, efficiency, and improved eye safety when compared to high peak-power diodes. Because of the improved eye safety, the API provides user-demanded features like video output and extended range gates in the active as well as passive imaging modes. Like any other night vision device, the API depends on natural illumination of the scene for passive operation. Although it has been known for decades that "starlight" illumination is actually from diffuse airglow emissions, the research described in this dissertation provides the first estimates of the global and temporal variation of ground illumination due to airglow. A third related element of the current research establishes the impact of atmospheric aerosols on API performance. We know from day experience that atmospheric scattering of sunlight into the imager line-of-sight can blind the imager and drastically degrade performance. Atmospheric scattering of sunlight is extensively covered in the literature. However, previous literature did not cover the impact of atmospheric scattering when the target is diffusely illuminated by airglow.

A quantum diffusion law

NASA Astrophysics Data System (ADS)

Satpathi, Urbashi; Sinha, Supurna; Sorkin, Rafael D.

2017-12-01

We analyse diffusion at low temperature by bringing the fluctuation-dissipation theorem (FDT) to bear on a physically natural, viscous response-function R(t) . The resulting diffusion-law exhibits several distinct regimes of time and temperature, each with its own characteristic rate of spreading. As with earlier analyses, we find logarithmic spreading in the quantum regime, indicating that this behavior is robust. A consistent R(t) must satisfy the key physical requirements of Wightman positivity and passivity, and we prove that ours does so. We also prove in general that these two conditions are equivalent when the FDT holds. Given current technology, our diffusion law can be tested in a laboratory with ultra cold atoms.

Performance tests of three types of air-sampling bags on organic solvent vapor retention.

PubMed

Fukui, Yoshinari; Kanemaru, Ai; Nagasawa, Yasuhiro; Kawakami, Takuya; Iwata, Toyoto; Murata, Katsuyuki; Ohashi, Fumiko; Ikeda, Masayuki

2013-01-01

Performance of two new air sampling bags [the transparent bag (TP bag) and the semi-transparent bag (ST bag)] was examined as possible surrogates for the traditional PVF bag (the Ref bag). Solvent vapor mixture of butyl acetate, chloroform, ethyl acetate, isopropyl alcohol and toluene at administrative control levels were introduced to each bag (n=5 for each of the three types), and the decay in the concentrations (by%) was followed by use of a gas auto-sampler - FID-GC system. A trend of time-dependent decay was noted for all types including the Ref bag. When the performance was compared, the TP bag was equal to or even better than the Ref bag. In contrast, the performance of the ST bag was comparable to that of the other two types of bags with regard to toluene and chloroform when the storage time was short, but poorer than others for the other three solvents throughout the test period. The TP bag may be a bag of choice when the storage time is extended (e.g., up to 48 h) although this bag is physically less robust and requires careful handling. The ST bag may be used when analysis will be completed within 24 h.

Passive Ventricular Mechanics Modelling Using MRI of Structure and Function

PubMed Central

Wang, V.Y.; Lam, H.I.; Ennis, D.B.; Young, A.A.; Nash, M.P.

2009-01-01

Patients suffering from dilated cardiomyopathy or myocardial infarction can develop left ventricular (LV) diastolic impairment. The LV remodels its structure and function to adapt to pathophysiological changes in geometry and loading conditions and this remodeling process can alter the passive ventricular mechanics. In order to better understand passive ventricular mechanics, a LV finite element model was developed to incorporate physiological and mechanical information derived from in vivo magnetic resonance imaging (MRI) tissue tagging, in vivo LV cavity pressure recording and ex vivo diffusion tensor MRI (DTMRI) of a canine heart. MRI tissue tagging enables quantitative evaluation of cardiac mechanical function with high spatial and temporal resolution, whilst the direction of maximum water diffusion (the primary eigenvector) in each voxel of a DTMRI directly correlates with the myocardial fibre orientation. This model was customized to the geometry of the canine LV during diastasis by fitting the segmented epicardial and endocardial surface data from tagged MRI using nonlinear finite element fitting techniques. Myofibre orientations, extracted from DTMRI of the same heart, were incorporated into this geometric model using a free form deformation methodology. Pressure recordings, temporally synchronized to the tissue tagging MRI data, were used to simulate the LV deformation during diastole. Simulation of the diastolic LV mechanics allowed us to estimate the stiffness of the passive LV myocardium based on kinematic data obtained from tagged MRI. This integrated physiological model will allow more insight into the regional passive diastolic mechanics of the LV on an individualized basis, thereby improving our understanding of the underlying structural basis of mechanical dysfunction in pathological conditions. PMID:18982680

CdCl2 Passivation of Polycrystalline CdMgTe and CdZnTe Absorbers for Tandem Photovoltaic Cells

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

Metzger, Wyatt K; Swanson, Drew; Reich, Carey

As single-junction silicon solar cells approach their theoretical limits, tandems provide the primary path to higher efficiencies. CdTe alloys can be tuned with magnesium (CdMgTe) or zinc (CdZnTe) for ideal tandem pairing with silicon. A II-VI/Si tandem holds the greatest promise for inexpensive, high-efficiency top cells that can be quickly deployed in the market using existing polycrystalline CdTe manufacturing lines combined with mature silicon production lines. Currently, all high efficiency polycrystalline CdTe cells require a chloride-based passivation process to passivate grain boundaries and bulk defects. This research examines the rich chemistry and physics that has historically limited performance when extendingmore » Cl treatments to polycrystalline 1.7-eV CdMgTe and CdZnTe absorbers. A combination of transmittance, quantum efficiency, photoluminescence, transmission electron microscopy, and energy-dispersive X-ray spectroscopy clearly reveals that during passivation, Mg segregates and out-diffuses, initially at the grain boundaries but eventually throughout the bulk. CdZnTe exhibits similar Zn segregation behavior; however, the onset and progression is localized to the back of the device. After passivation, CdMgTe and CdZnTe can render a layer that is reduced to predominantly CdTe electro-optical behavior. Contact instabilities caused by inter-diffusion between the layers create additional complications. The results outline critical issues and paths for these materials to be successfully implemented in Si-based tandems and other applications.« less

Passive ventricular mechanics modelling using MRI of structure and function.

PubMed

Wang, V Y; Lam, H I; Ennis, D B; Young, A A; Nash, M P

2008-01-01

Patients suffering from dilated cardiomyopathy or myocardial infarction can develop left ventricular (LV) diastolic impairment. The LV remodels its structure and function to adapt to pathophysiological changes in geometry and loading conditions and this remodeling process can alter the passive ventricular mechanics. In order to better understand passive ventricular mechanics, a LV finite element model was developed to incorporate physiological and mechanical information derived from in vivo magnetic resonance imaging (MRI) tissue tagging, in vivo LV cavity pressure recording and ex vivo diffusion tensor MRI (DTMRI) of a canine heart. MRI tissue tagging enables quantitative evaluation of cardiac mechanical function with high spatial and temporal resolution, whilst the direction of maximum water diffusion (the primary eigenvector) in each voxel of a DTMRI directly correlates with the myocardial fibre orientation. This model was customized to the geometry of the canine LV during diastasis by fitting the segmented epicardial and endocardial surface data from tagged MRI using nonlinear finite element fitting techniques. Myofibre orientations, extracted from DTMRI of the same heart, were incorporated into this geometric model using a free form deformation methodology. Pressure recordings, temporally synchronized to the tissue tagging MRI data, were used to simulate the LV deformation during diastole. Simulation of the diastolic LV mechanics allowed us to estimate the stiffness of the passive LV myocardium based on kinematic data obtained from tagged MRI. This integrated physiological model will allow more insight into the regional passive diastolic mechanics of the LV on an individualized basis, thereby improving our understanding of the underlying structural basis of mechanical dysfunction in pathological conditions.

Porous Electrode Studies.

DTIC Science & Technology

1980-07-01

the reac- tion modes of the Ag/AgCl, AgO/Ag 2O/Ag, and Zn/ ZnO electrodes and to testing various theories that predict electrode behavior. v LOCKHEED...of sudden passivation was related to a simul- taneous precipitation of flocculent ZnO , and this passivation was removed by addi- tion of fresh...vation occurred more slowly by covering with a thin, adherent film, and that a dis- solution, diffusion, deposition mode prevailed in the formation of ZnO

Subcellular localisation of BAG-1 and its regulation of vitamin D receptor-mediated transactivation and involucrin expression in oral keratinocytes: Implications for oral carcinogenesis

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

Lee, San San; Crabb, Simon J.; Janghra, Nari

2007-09-10

In oral cancers, cytoplasmic BAG-1 overexpression is a marker of poor prognosis. BAG-1 regulates cellular growth, differentiation and survival through interactions with diverse proteins, including the vitamin D receptor (VDR), a key regulator of keratinocyte growth and differentiation. BAG-1 is expressed ubiquitously in human cells as three major isoforms of 50 kDa (BAG-1L), 46 kDa (BAG-1M) and 36 kDa (BAG-1S) from a single mRNA. In oral keratinocytes BAG-1L, but not BAG-1M and BAG-1S, enhanced VDR transactivation in response to 1{alpha},25-dihydroxyvitamin D{sub 3.} BAG-1L was nucleoplasmic and nucleolar, whereas BAG-1S and BAG-1M were cytoplasmic and nucleoplasmic in localisation. Having identified themore » nucleolar localisation sequence in BAG-1L, we showed that mutation of this sequence did not prevent BAG-1L from potentiating VDR activity. BAG-1L also potentiated transactivation of known vitamin-D-responsive gene promoters, osteocalcin and 24-hydroxylase, and enhanced VDR-dependent transcription and protein expression of the keratinocyte differentiation marker, involucrin. These results demonstrate endogenous gene regulation by BAG-1L by potentiating nuclear hormone receptor function and suggest a role for BAG-1L in 24-hydroxylase regulation of vitamin D metabolism and the cellular response of oral keratinocytes to 1{alpha},25-dihydroxyvitamin D{sub 3}. By contrast to the cytoplasmic BAG-1 isoforms, BAG-1L may act to suppress tumorigenesis.« less

Effect of dual-dielectric hydrogen-diffusion barrier layers on the performance of low-temperature processed transparent InGaZnO thin-film transistors

NASA Astrophysics Data System (ADS)

Tari, Alireza; Wong, William S.

2018-02-01

Dual-dielectric SiOx/SiNx thin-film layers were used as back-channel and gate-dielectric barrier layers for bottom-gate InGaZnO (IGZO) thin-film transistors (TFTs). The concentration profiles of hydrogen, indium, gallium, and zinc oxide were analyzed using secondary-ion mass spectroscopy characterization. By implementing an effective H-diffusion barrier, the hydrogen concentration and the creation of H-induced oxygen deficiency (H-Vo complex) defects during the processing of passivated flexible IGZO TFTs were minimized. A bilayer back-channel passivation layer, consisting of electron-beam deposited SiOx on plasma-enhanced chemical vapor-deposition (PECVD) SiNx films, effectively protected the TFT active region from plasma damage and minimized changes in the chemical composition of the semiconductor layer. A dual-dielectric PECVD SiOx/PECVD SiNx gate-dielectric, using SiOx as a barrier layer, also effectively prevented out-diffusion of hydrogen atoms from the PECVD SiNx-gate dielectric to the IGZO channel layer during the device fabrication.

Impurity gettering in semiconductors

DOEpatents

Sopori, B.L.

1995-06-20

A process for impurity gettering in a semiconductor substrate or device such as a silicon substrate or device is disclosed. The process comprises hydrogenating the substrate or device at the back side thereof with sufficient intensity and for a time period sufficient to produce a damaged back side. Thereafter, the substrate or device is illuminated with electromagnetic radiation at an intensity and for a time period sufficient to cause the impurities to diffuse to the back side and alloy with a metal there present to form a contact and capture the impurities. The impurity gettering process also can function to simultaneously passivate defects within the substrate or device, with the defects likewise diffusing to the back side for simultaneous passivation. Simultaneously, substantially all hydrogen-induced damage on the back side of the substrate or device is likewise annihilated. Also taught is an alternate process comprising thermal treatment after hydrogenation of the substrate or device at a temperature of from about 500 C to about 700 C for a time period sufficient to cause the impurities to diffuse to the damaged back side thereof for subsequent capture by an alloying metal. 1 fig.

Impurity gettering in semiconductors

DOEpatents

Sopori, Bhushan L.

1995-01-01

A process for impurity gettering in a semiconductor substrate or device such as a silicon substrate or device. The process comprises hydrogenating the substrate or device at the back side thereof with sufficient intensity and for a time period sufficient to produce a damaged back side. Thereafter, the substrate or device is illuminated with electromagnetic radiation at an intensity and for a time period sufficient to cause the impurities to diffuse to the back side and alloy with a metal there present to form a contact and capture the impurities. The impurity gettering process also can function to simultaneously passivate defects within the substrate or device, with the defects likewise diffusing to the back side for simultaneous passivation. Simultaneously, substantially all hydrogen-induced damage on the back side of the substrate or device is likewise annihilated. Also taught is an alternate process comprising thermal treatment after hydrogenation of the substrate or device at a temperature of from about 500.degree. C. to about 700.degree. C. for a time period sufficient to cause the impurities to diffuse to the damaged back side thereof for subsequent capture by an alloying metal.

Very Hard Corrosion-Resistant Roll-Bonded Cr Coating on Mild Steel in Presence of Graphite

NASA Astrophysics Data System (ADS)

Kumar, Pankaj; Khara, S.; Shekhar, S.; Mondal, K.

2017-12-01

The present work discusses the development of very hard Cr and Cr-carbide coating by roll bonding of Cr powder on a mild steel followed by annealing at 800, 1000, 1100 and 1200 °C with and without the presence of graphite powder packing in argon environment. In addition, the effect of a roll skin pass of 5% prior to the application of coating was studied. The presence of graphite allows diffusion of both carbon and Cr in the mild steel substrate, leading to the formation of Cr-carbide on the outer surface, making the surface very hard (VHN 1800). Depending on the annealing temperature and processing condition, diffusion layer thickness of Cr is found to be in the range of 10-250 μm with Cr content of 12.5-15 wt.% across the diffusion layer. Excellent stable passivity of the coated surface is observed in 0.2 N H2SO4, which is comparable to a highly passivating 304 stainless steel, and very low corrosion rate of the coating is observed as compared to the substrate mild steel.

Classification of longissimus lumborum muscle spindle afferents in the anaesthetized cat

PubMed Central

Durbaba, R; Taylor, A; Ellaway, P H; Rawlinson, S

2006-01-01

Recordings have been made from 127 single muscle spindle afferents from the longissimus lumborum muscles of anaesthetized cats. They have been characterized by their responses to passive muscle stretch and the effects of succinylcholine (SCh) and by their sensitivity to vibration. The use of SCh permitted the assessment for each afferent of the influence of bag1 (b1) and bag2 (b2) intrafusal muscle fibres. From this, on the assumption that all afferents were affected by chain (c) fibres, they were classified in four groups: b1b2c (41.9%), b2c (51.4%), b1c (1.3%) and c (5.4%). All the afferents with b1 influence were able to respond one to one to vibration at frequencies above 100 Hz and were considered to belong to primary endings. On the basis of the vibration test, 64% of the b2c type afferents appeared to be primaries and 36% secondaries. Of the units classified as primaries, 41% were designated as b2c and would not therefore be able to respond to dynamic fusimotor activity. The significance of this relatively high proportion of b2c-type spindle primary afferents is discussed in relation to the specialized postural function of the back muscles. PMID:16410280

Fluorescent Recovery after Photobleaching (FRAP) Analysis of Nuclear Export Rates Identifies Intrinsic Features of Nucleocytoplasmic Transport*

PubMed Central

Cardarelli, Francesco; Tosti, Luca; Serresi, Michela; Beltram, Fabio; Bizzarri, Ranieri

2012-01-01

A quantitative description of carrier-mediated nuclear export in live cells is presented. To this end, we fused a prototypical leucine-rich nuclear export signal (NES) to GFP as a cargo model and expressed the fluorescent chimera in live CHO-K1 cells. By modeling FRAP data, we calculate the NES affinity for the export machinery and the maximum rate of nuclear export achievable at saturation of endogenous carriers. The measured active-export time through the Nuclear Pore Complex (NPC) is 18 ms, remarkably similar to the previously determined active-import rate. Also, our results reveal that active export/import and active export/passive diffusion fluxes are uncoupled, thus complementing previous reports on active import/passive diffusion uncoupling. These findings suggest differential gating at the NPC level. PMID:22190681

Correction of Altitude-Induced Changes in Performance of the Volumetric Diffusive Respirator

DTIC Science & Technology

2017-04-05

to a plateau pressure. The positive pressure delivery of each percussive pulse is followed by a passive fall in pressure as the spring moves the ...AFRL-SA-WP-SR-2017-0007 Correction of Altitude- Induced Changes in Performance of the Volumetric Diffusive Respirator Thomas...Blakeman, MSc RRT April 2017 Air Force Research Laboratory 711th Human Performance Wing U.S. Air Force School of Aerospace

Anomalous, non-Gaussian tracer diffusion in crowded two-dimensional environments

NASA Astrophysics Data System (ADS)

Ghosh, Surya K.; Cherstvy, Andrey G.; Grebenkov, Denis S.; Metzler, Ralf

2016-01-01

A topic of intense current investigation pursues the question of how the highly crowded environment of biological cells affects the dynamic properties of passively diffusing particles. Motivated by recent experiments we report results of extensive simulations of the motion of a finite sized tracer particle in a heterogeneously crowded environment made up of quenched distributions of monodisperse crowders of varying sizes in finite circular two-dimensional domains. For given spatial distributions of monodisperse crowders we demonstrate how anomalous diffusion with strongly non-Gaussian features arises in this model system. We investigate both biologically relevant situations of particles released either at the surface of an inner domain or at the outer boundary, exhibiting distinctly different features of the observed anomalous diffusion for heterogeneous distributions of crowders. Specifically we reveal an asymmetric spreading of tracers even at moderate crowding. In addition to the mean squared displacement (MSD) and local diffusion exponent we investigate the magnitude and the amplitude scatter of the time averaged MSD of individual tracer trajectories, the non-Gaussianity parameter, and the van Hove correlation function. We also quantify how the average tracer diffusivity varies with the position in the domain with a heterogeneous radial distribution of crowders and examine the behaviour of the survival probability and the dynamics of the tracer survival probability. Inter alia, the systems we investigate are related to the passive transport of lipid molecules and proteins in two-dimensional crowded membranes or the motion in colloidal solutions or emulsions in effectively two-dimensional geometries, as well as inside supercrowded, surface adhered cells.

Mesure du coewicient d'absorption optique dans le silicium multicristallin de type P pour photopiles solaires

NASA Astrophysics Data System (ADS)

Gervais, J.

1993-07-01

The minority carrier diffusion length L characterizes the electrical quality of multicrystalline silicon wafers used for photovoltaics. Its determination before and after different treatments (impurity diffusion, passivation, metallisation) is needfull and requires the accurate knowledge of the optical absorption coefficient α in the near infrared. We have determinated the spectral variation of α in the range between 0.86 and 1.06 μm and we propose an analytic expression which is very close to those proposed for solar grade single crystals. In addition we have verified that the values of α are not affected by long phosphorus diffusion needed to getter metallic impurities. La longueur de diffusion des porteurs minoritaires L caractérise la qualité du silicium multicristallin utilisé pour la conversion photovoltaïque. Sa détermination avant et après les divers traitements (diffusion d'impuretés, passivation des défauts, métallisation) est indispensable et nécessite la connaissance précise du coefficient d'absorption optique α dans le proche infrarouge. Nous avons déterminé expérimentalement la variation spectrale de α entre 0,86 et 1,06 μm et nous proposons un développement qui est très proche de ceux trouvés dans des monocristaux de silicium de qualité solaire. La variation de α n'est pas influencée par des diffusions de phosphore prolongées nécessaires à l'extraction et au piégeage d'impuretés métalliques.

Localization of Protein Aggregation in Escherichia coli Is Governed by Diffusion and Nucleoid Macromolecular Crowding Effect

PubMed Central

Coquel, Anne-Sophie; Jacob, Jean-Pascal; Primet, Mael; Demarez, Alice; Dimiccoli, Mariella; Julou, Thomas; Moisan, Lionel

2013-01-01

Aggregates of misfolded proteins are a hallmark of many age-related diseases. Recently, they have been linked to aging of Escherichia coli (E. coli) where protein aggregates accumulate at the old pole region of the aging bacterium. Because of the potential of E. coli as a model organism, elucidating aging and protein aggregation in this bacterium may pave the way to significant advances in our global understanding of aging. A first obstacle along this path is to decipher the mechanisms by which protein aggregates are targeted to specific intercellular locations. Here, using an integrated approach based on individual-based modeling, time-lapse fluorescence microscopy and automated image analysis, we show that the movement of aging-related protein aggregates in E. coli is purely diffusive (Brownian). Using single-particle tracking of protein aggregates in live E. coli cells, we estimated the average size and diffusion constant of the aggregates. Our results provide evidence that the aggregates passively diffuse within the cell, with diffusion constants that depend on their size in agreement with the Stokes-Einstein law. However, the aggregate displacements along the cell long axis are confined to a region that roughly corresponds to the nucleoid-free space in the cell pole, thus confirming the importance of increased macromolecular crowding in the nucleoids. We thus used 3D individual-based modeling to show that these three ingredients (diffusion, aggregation and diffusion hindrance in the nucleoids) are sufficient and necessary to reproduce the available experimental data on aggregate localization in the cells. Taken together, our results strongly support the hypothesis that the localization of aging-related protein aggregates in the poles of E. coli results from the coupling of passive diffusion-aggregation with spatially non-homogeneous macromolecular crowding. They further support the importance of “soft” intracellular structuring (based on macromolecular crowding) in diffusion-based protein localization in E. coli. PMID:23633942

Preharvest bagging with wavelength-selective materials enhances development and quality of mango (Mangifera indica L.) cv. Nam Dok Mai #4.

PubMed

Chonhenchob, Vanee; Kamhangwong, Damrongpol; Kruenate, Jittiporn; Khongrat, Krittaphat; Tangchantra, Nantavat; Wichai, Uthai; Singh, S Paul

2011-03-15

Preharvest bagging has been shown to improve development and quality of fruits. Different light transmittance bags showed different effects on fruit quality. This study presents the benefits of using newly developed plastic bagging materials with different wavelength-selective characteristics for mangoes (cv. Nam Dok Mai #4). Mangoes were bagged at 45 days after full bloom (DAFB) and randomly harvested at 65, 75, 85, 95, and 105 DAFB. The bags were removed on the harvest days. The wavelength-selective bags (no pigment, yellow, red, blue/violet, blue) were compared with the Kraft paper bag with black paper liner, which is currently used commercially for several fruits, and with non-bagging as a control. Bagging significantly (p⩽0.05) reduced diseases and blemishes. Mango weight at 95 DAFB was increased approximately 15% by VM and V plastic bagging, as compared to paper bagging and control. Plastic bagging accelerated mango ripening as well as growth. Plastic-bagged mangoes reached maturity stage at 95 DAFB, while non-bagged mangoes reached maturity stage at 105 DAFB. Paper bagging resulted in a pale-yellow peel beginning at 65 DAFB, while plastic bagging improved peel glossiness. Preharvest bagging with different wavelength-selective materials affected mango development and quality. Bagging mangoes with VM and V materials could reduce peel defects and diseases, increase weight, size, and sphericity, improve peel appearance, and shorten the development periods of mangoes. The results suggest a favorable practice using the newly developed VM and V plastic bags in the production of mangoes, and possibly other fruits as well. Copyright © 2010 Society of Chemical Industry.

Effectiveness of the ZeroFly® storage bag fabric against stored-product insects

USDA-ARS?s Scientific Manuscript database

The ZeroFly® Storage Bag is a polypropylene bag (PP) which has deltamethrin incorporated in its fibers, and represents a novel approach to reducing stored-product insect pest-related postharvest losses. Fabric samples from ZeroFly bags, polypropylene (PP) bags, jute bags, malathion-treated PP bags, ...

Coexistence of passive and carrier-mediated processes in drug transport.

PubMed

Sugano, Kiyohiko; Kansy, Manfred; Artursson, Per; Avdeef, Alex; Bendels, Stefanie; Di, Li; Ecker, Gerhard F; Faller, Bernard; Fischer, Holger; Gerebtzoff, Grégori; Lennernaes, Hans; Senner, Frank

2010-08-01

The permeability of biological membranes is one of the most important determinants of the pharmacokinetic processes of a drug. Although it is often accepted that many drug substances are transported across biological membranes by passive transcellular diffusion, a recent hypothesis speculated that carrier-mediated mechanisms might account for the majority of membrane drug transport processes in biological systems. Based on evidence of the physicochemical characteristics and of in vitro and in vivo findings for marketed drugs, as well as results from real-life discovery and development projects, we present the view that both passive transcellular processes and carrier-mediated processes coexist and contribute to drug transport activities across biological membranes.

A Fractional PDE Approach to Turbulent Mixing; Part II: Numerical Simulation

NASA Astrophysics Data System (ADS)

Samiee, Mehdi; Zayernouri, Mohsen

2016-11-01

We propose a generalizing fractional order transport model of advection-diffusion kind with fractional time- and space-derivatives, governing the evolution of passive scalar turbulence. This approach allows one to incorporate the nonlocal and memory effects in the underlying anomalous diffusion i.e., sub-to-standard diffusion to model the trapping of particles inside the eddied, and super-diffusion associated with the sudden jumps of particles from one coherent region to another. For this nonlocal model, we develop a high order numerical (spectral) method in addition to a fast solver, examined in the context of some canonical problems. PhD student, Department of Mechanical Engineering, & Department Computational Mathematics, Science, and Engineering.

BAG-1 enhances cell-cell adhesion, reduces proliferation and induces chaperone-independent suppression of hepatocyte growth factor-induced epidermal keratinocyte migration

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

Hinitt, C.A.M.; Wood, J.; Lee, S.S.

2010-08-01

Cell motility is important in maintaining tissue homeostasis, facilitating epithelial wound repair and in tumour formation and progression. The aim of this study was to determine whether BAG-1 isoforms regulate epidermal cell migration in in vitro models of wound healing. In the human epidermal cell line HaCaT, endogenous BAG-1 is primarily nuclear and increases with confluence. Both transient and stable p36-Bag-1 overexpression resulted in increased cellular cohesion. Stable transfection of either of the three human BAG-1 isoforms p36-Bag-1 (BAG-1S), p46-Bag-1 (BAG-1M) and p50-Bag-1 (BAG-1L) inhibited growth and wound closure in serum-containing medium. However, in response to hepatocyte growth factor (HGF)more » in serum-free medium, BAG-1S/M reduced communal motility and colony scattering, but BAG-1L did not. In the presence of HGF, p36-Bag-1 transfectants retained proliferative response to HGF with no change in ERK1/2 activation. However, the cells retained E-cadherin localisation at cell-cell junctions and exhibited pronounced cortical actin. Point mutations in the BAG domain showed that BAG-1 inhibition of motility is independent of its function as a chaperone regulator. These findings are the first to suggest that BAG-1 plays a role in regulating cell-cell adhesion and suggest an important function in epidermal cohesion.« less

Storage of Maize in Purdue Improved Crop Storage (PICS) Bags

PubMed Central

2017-01-01

Interest in using hermetic technologies as a pest management solution for stored grain has risen in recent years. One hermetic approach, Purdue Improved Crop Storage (PICS) bags, has proven successful in controlling the postharvest pests of cowpea. This success encouraged farmers to use of PICS bags for storing other crops including maize. To assess whether maize can be safely stored in PICS bags without loss of quality, we carried out laboratory studies of maize grain infested with Sitophilus zeamais (Motshulsky) and stored in PICS triple bags or in woven polypropylene bags. Over an eight month observation period, temperatures in the bags correlated with ambient temperature for all treatments. Relative humidity inside PICS bags remained constant over this period despite the large changes that occurred in the surrounding environment. Relative humidity in the woven bags followed ambient humidity closely. PICS bags containing S. zeamais-infested grain saw a significant decline in oxygen compared to the other treatments. Grain moisture content declined in woven bags, but remained high in PICS bags. Seed germination was not significantly affected over the first six months in all treatments, but declined after eight months of storage when infested grain was held in woven bags. Relative damage was low across treatments and not significantly different between treatments. Overall, maize showed no signs of deterioration in PICS bags versus the woven bags and PICS bags were superior to woven bags in terms of specific metrics of grain quality. PMID:28072835

Mixing of a passive scalar by the instability of a differentially rotating axial pinch

NASA Astrophysics Data System (ADS)

Paredes, A.; Gellert, M.; Rüdiger, G.

2016-04-01

The mean-field diffusion of passive scalars such as lithium, beryllium or temperature dispersals due to the magnetic Tayler instability of a rotating axial pinch is considered. Our study is carried out within a Taylor-Couette setup for two rotation laws: solid-body quasi-Kepler rotation. The minimum magnetic Prandtl number used is 0.05, and the molecular Schmidt number Sc of the fluid varies between 0.1 and 2. An effective diffusivity coefficient for the mixing is numerically measured by the decay of a prescribed concentration peak located between both cylinder walls. We find that only models with Sc exceeding 0.1 basically provide finite instability-induced diffusivity values. We also find that for quasi-Kepler rotation at a magnetic Mach number Mm ≃ 2, the flow transits from the slow-rotation regime to the fast-rotation regime that is dominated by the Taylor-Proudman theorem. For fixed Reynolds number, the relation between the normalized turbulent diffusivity and the Schmidt number of the fluid is always linear so that also a linear relation between the instability-induced diffusivity and the molecular viscosity results, just in the sense proposed by Schatzman (1977, A&A, 573, 80). The numerical value of the coefficient in this relation reaches a maximum at Mm ≃ 2 and decreases for larger Mm, implying that only toroidal magnetic fields on the order of 1 kG can exist in the solar tachocline.

Quantitative assessment of passive electrical properties of the cardiac T-tubular system by FRAP microscopy

PubMed Central

Scardigli, M.; Ferrantini, C.; Gabbrielli, T.; Silvestri, L.; Coppini, R.; Tesi, C.; Rog-Zielinska, E. A.; Kohl, P.; Cerbai, E.; Poggesi, C.; Pavone, F. S.; Sacconi, L.

2017-01-01

Well-coordinated activation of all cardiomyocytes must occur on every heartbeat. At the cell level, a complex network of sarcolemmal invaginations, called the transverse-axial tubular system (TATS), propagates membrane potential changes to the cell core, ensuring synchronous and uniform excitation–contraction coupling. Although myocardial conduction of excitation has been widely described, the electrical properties of the TATS remain mostly unknown. Here, we exploit the formal analogy between diffusion and electrical conductivity to link the latter with the diffusional properties of TATS. Fluorescence recovery after photobleaching (FRAP) microscopy is used to probe the diffusion properties of TATS in isolated rat cardiomyocytes: A fluorescent dextran inside TATS lumen is photobleached, and signal recovery by diffusion of unbleached dextran from the extracellular space is monitored. We designed a mathematical model to correlate the time constant of fluorescence recovery with the apparent diffusion coefficient of the fluorescent molecules. Then, apparent diffusion is linked to electrical conductivity and used to evaluate the efficiency of the passive spread of membrane depolarization along TATS. The method is first validated in cells where most TATS elements are acutely detached by osmotic shock and then applied to probe TATS electrical conductivity in failing heart cells. We find that acute and pathological tubular remodeling significantly affect TATS electrical conductivity. This may explain the occurrence of defects in action potential propagation at the level of single T-tubules, recently observed in diseased cardiomyocytes. PMID:28507142

Tantalum oxide/silicon nitride: A negatively charged surface passivation stack for silicon solar cells

NASA Astrophysics Data System (ADS)

Wan, Yimao; Bullock, James; Cuevas, Andres

2015-05-01

This letter reports effective passivation of crystalline silicon (c-Si) surfaces by thermal atomic layer deposited tantalum oxide (Ta2O5) underneath plasma enhanced chemical vapour deposited silicon nitride (SiNx). Cross-sectional transmission electron microscopy imaging shows an approximately 2 nm thick interfacial layer between Ta2O5 and c-Si. Surface recombination velocities as low as 5.0 cm/s and 3.2 cm/s are attained on p-type 0.8 Ω.cm and n-type 1.0 Ω.cm c-Si wafers, respectively. Recombination current densities of 25 fA/cm2 and 68 fA/cm2 are measured on 150 Ω/sq boron-diffused p+ and 120 Ω/sq phosphorus-diffused n+ c-Si, respectively. Capacitance-voltage measurements reveal a negative fixed insulator charge density of -1.8 × 1012 cm-2 for the Ta2O5 film and -1.0 × 1012 cm-2 for the Ta2O5/SiNx stack. The Ta2O5/SiNx stack is demonstrated to be an excellent candidate for surface passivation of high efficiency silicon solar cells.

Retardation mechanism of ultrathin Al2O3 interlayer on Y2O3 passivated gallium nitride surface.

PubMed

Quah, Hock Jin; Cheong, Kuan Yew

2014-05-28

A systematic investigation was carried out by incorporating an ultrathin aluminum oxide (Al2O3) as an interlayer between yttrium oxide (Y2O3) passivation layer and GaN substrate. The sandwiched samples were then subjected to postdeposition annealing in oxygen ambient from 400 to 800 °C. The Al2O3 interlayer was discovered to play a significant role in slowing down inward diffusion of oxygen through the Y2O3 passivation layer as well as in impeding outward diffusion of Ga(3+) and N(3-) from the decomposed GaN surface. These beneficial effects have suppressed subsequent formation of interfacial layer. A mechanism in association with the function of Al2O3 as an interlayer was suggested and discussed. The mechanism was explicitly described on the basis of the obtained results from X-ray diffraction, X-ray photoelectron spectroscopy, energy-filtered transmission electron microscopy (TEM), high resolution TEM, and electron energy loss spectroscopy line scan. A correlation between the proposed mechanism and metal-oxide-semiconductor characteristics of Y2O3/Al2O3/GaN structure has been proposed.

Resolvent-based modeling of passive scalar dynamics in wall-bounded turbulence

NASA Astrophysics Data System (ADS)

Dawson, Scott; Saxton-Fox, Theresa; McKeon, Beverley

2017-11-01

The resolvent formulation of the Navier-Stokes equations expresses the system state as the output of a linear (resolvent) operator acting upon a nonlinear forcing. Previous studies have demonstrated that a low-rank approximation of this linear operator predicts many known features of incompressible wall-bounded turbulence. In this work, this resolvent model for wall-bounded turbulence is extended to include a passive scalar field. This formulation allows for a number of additional simplifications that reduce model complexity. Firstly, it is shown that the effect of changing scalar diffusivity can be approximated through a transformation of spatial wavenumbers and temporal frequencies. Secondly, passive scalar dynamics may be studied through the low-rank approximation of a passive scalar resolvent operator, which is decoupled from velocity response modes. Thirdly, this passive scalar resolvent operator is amenable to approximation by semi-analytic methods. We investigate the extent to which this resulting hierarchy of models can describe and predict passive scalar dynamics and statistics in wall-bounded turbulence. The support of AFOSR under Grant Numbers FA9550-16-1-0232 and FA9550-16-1-0361 is gratefully acknowledged.

Mesoscale Elucidation of Surface Passivation in the Li-Sulfur Battery Cathode.

PubMed

Liu, Zhixiao; Mukherjee, Partha P

2017-02-15

The cathode surface passivation caused by Li 2 S precipitation adversely affects the performance of lithium-sulfur (Li-S) batteries. Li 2 S precipitation is a complicated mesoscale process involving adsorption, desorption and diffusion kinetics, which are affected profoundly by the reactant concentration and operating temperature. In this work, a mesoscale interfacial model is presented to study the growth of Li 2 S film on carbon cathode surface. Li 2 S film growth experiences nucleation, isolated Li 2 S island growth and island coalescence. The slow adsorption rate at small S 2- concentration inhibits the formation of nucleation seeds and the lateral growth of Li 2 S islands, which deters surface passivation. An appropriate operating temperature, especially in the medium-to-high temperature range, can also defer surface passivation. Fewer Li 2 S nucleation seeds form in such an operating temperature range, thereby facilitating heterogeneous growth and potentially inhibiting the lateral growth of the Li 2 S film, which may ultimately result in reduced surface passivation. The high specific surface area of the cathode microstructure is expected to mitigate the surface passivation.

49 CFR 178.520 - Standards for textile bags.

Code of Federal Regulations, 2011 CFR

2011-10-01

... for a sift-proof textile bag; and (3) 5L3 for a water-resistant textile bag. (b) Construction... bag. (2) Bags, sift-proof, 5L2: The bag must be made sift-proof, by appropriate means, such as by the...

Unit-Dose Bags For Formulating Intravenous Solutions

NASA Technical Reports Server (NTRS)

Finley, Mike; Kipp, Jim; Scharf, Mike; Packard, Jeff; Owens, Jim

1993-01-01

Smaller unit-dose flowthrough bags devised for use with large-volume parenteral (LVP) bags in preparing sterile intravenous solutions. Premeasured amount of solute stored in such unit-dose bag flushed by predetermined amount of water into LVP bag. Relatively small number of LVP bags used in conjunction with smaller unit-dose bags to formulate large number of LVP intravenous solutions in nonsterile environment.

[Effects of bagging on the microenvironment, yield and quality of overwintering tomato].

PubMed

Wang, Lei; Xu, Kun; Bei, Feng; Gao, Fang-Sheng

2007-04-01

Taking overwintering tomato variety "L402" as test material, this paper studied the effects of bagging with different texture bags on its fruit enlarging and quality, and the microenvironment within the bags. The results showed that bagging could change the microenvironment of fruit development, promote fruit maturing in advance, and improve fruit mass and quality. The light intensity and humidity in parchment bag were at the intermediate of those in plastic and no-spinning cloth bags, and the temperature was the highest among all treatments, except that it was lower than that in plastic bag at forenoon. The fruit enlarging rate in parchment bag was also the highest, and the single fruit mass increased by 15.34%, compared with the control. However, the fruit soluble solid, soluble sugar, and vitamine C contents and the sugar/acid ratio in all bagging treatments were lower than those of the control, suggesting that bagging debased the nutritive quality and the tastiness of tomato fruit. Due to the fact that bagging prevented the direct contact of fruit with pesticides, the fruit chlorpyrifos and betacypermethrin contents in parchment and plastic bags were lower than the control, except that the chlorpyrifos content in no-spinning cloth bag was higher.

Passive antibody-mediated immunotherapy for the treatment of malignant gliomas.

PubMed

Mitra, Siddhartha; Li, Gordon; Harsh, Griffith R

2010-01-01

Despite advances in understanding the molecular mechanisms of brain cancer, the outcome of patients with malignant gliomas treated according to the current standard of care remains poor. Novel therapies are needed, and immunotherapy has emerged with great promise. The diffuse infiltration of malignant gliomas is a major challenge to effective treatment; immunotherapy has the advantage of accessing the entire brain with specificity for tumor cells. Therapeutic immune approaches include cytokine therapy, passive immunotherapy, and active immunotherapy. Cytokine therapy involves the administration of immunomodulatory cytokines to activate the immune system. Active immunotherapy is the generation or augmentation of an immune response, typically by vaccination against tumor antigens. Passive immunotherapy connotes either adoptive therapy, in which tumor-specific immune cells are expanded ex vivo and reintroduced into the patient, or passive antibody-mediated therapy. In this article, the authors discuss the preclinical and clinical studies that have used passive antibody-mediated immunotherapy, otherwise known as serotherapy, for the treatment of malignant gliomas.

How have changes in front air bag designs affected frontal crash death rates? An update.

PubMed

Teoh, Eric R

2014-01-01

Provide updated death rates comparing latest generations of frontal air bags in fatal crashes. Rates of driver and right-front passenger deaths in frontal crashes per 10 million registered vehicle years were compared using Poisson marginal structural models for passenger vehicles equipped with air bags certified as advanced and compliant (CAC), sled-certified air bags with advanced features, and sled-certified air bags without any advanced features. Analyses of driver death rates were disaggregated by age group, gender, and belt use. CAC air bags were associated with slightly elevated frontal crash death rates for both drivers and right-front passengers compared to sled-certified air bags with advanced features, but the differences were not statistically significant. Sled-certified air bags with advanced features were associated with significant benefits for drivers and for right-front passengers compared to sled-certified air bags without advanced features. CAC air bags were associated with a significant increase in belted driver death rate and a comparable but nonsignificant decrease in unbelted driver death rate compared to sled-certified air bags with advanced features. Sled-certified air bags with advanced features were associated with a nonsignificant 2 percent increase in belted driver death rate and a significant 26 percent decrease in unbelted driver death rate, relative to sled-certified air bags without advanced features. Implementing advanced features in sled-certified air bags was beneficial overall to drivers and right-front passengers with sled-certified air bags. No overall benefit was observed for CAC air bags compared to sled-certified air bags with advanced features. Further study is needed to understand the apparent reduction in belted driver protection observed for CAC air bags.

Influence of wind-speed on short-duration NO2 measurements using Palmes and Ogawa passive diffusion samplers

NASA Astrophysics Data System (ADS)

Masey, Nicola; Gillespie, Jonathan; Heal, Mathew R.; Hamilton, Scott; Beverland, Iain J.

2017-07-01

We assessed the precision and accuracy of nitrogen dioxide (NO2) concentrations over 2-day, 3-day and 7-day exposure periods measured with the following types of passive diffusion samplers: standard (open) Palmes tubes; standard Ogawa samplers with commercially-prepared Ogawa absorbent pads (Ogawa[S]); and modified Ogawa samplers with absorbent-impregnated stainless steel meshes normally used in Palmes tubes (Ogawa[P]). We deployed these passive samplers close to the inlet of a chemiluminescence NO2 analyser at an urban background site in Glasgow, UK over 32 discrete measurement periods. Duplicate relative standard deviation was <7% for all passive samplers. The Ogawa[P], Ogawa[S] and Palmes samplers explained 93%, 87% and 58% of temporal variation in analyser concentrations respectively. Uptake rates for Palmes and Ogawa[S] samplers were positively and linearly associated with wind-speed (P < 0.01 and P < 0.05 respectively). Computation of adjusted uptake rates using average wind-speed observed during each sampling period increased the variation in analyser concentrations explained by Palmes and Ogawa[S] estimates to 90% and 92% respectively, suggesting that measurements can be corrected for shortening of diffusion path lengths due to wind-speed to improve the accuracy of estimates of short-term NO2 exposure. Monitoring situations where it is difficult to reliably estimate wind-speed variations, e.g. across multiple sites with different unknown exposures to local winds, and personal exposure monitoring, are likely to benefit from protection of these sampling devices from the effects of wind, for example by use of a mesh or membrane across the open end. The uptake rate of Ogawa[P] samplers was not associated with wind-speed resulting in a high correlation between estimated concentrations and observed analyser concentrations. The use of Palmes meshes in Ogawa[P] samplers reduced the cost of sampler preparation and removed uncertainty associated with the unknown manufacturing process for the commercially-prepared collection pads.

Parameters influencing the course of passive drug loading into lipid nanoemulsions.

PubMed

Göke, Katrin; Bunjes, Heike

2018-05-01

Passive drug loading can be used to effectively identify suitable colloidal lipid carrier systems for poorly water-soluble drugs. This method comprises incubation of preformed carrier systems with drug powder and subsequent determination of the resulting drug load of the carrier particles. Until now, the passive loading mechanism is unknown, which complicates reliable routine use. In this work, the influence of drug characteristics on the course of passive loading was investigated systematically varying drug surface area and drug solubility. Fenofibrate and flufenamic acid were used as model drugs; the carrier system was a trimyristin nanodispersion. Loading progress was analyzed by UV spectroscopy or by a novel method based on differential scanning calorimetry. While increasing drug solubility by micelle incorporation did not speed up passive loading, a large drug surface area and high water solubility were key parameters for fast loading. Since both factors are crucial in drug dissolution as described by the Noyes-Whitney equation, these findings point to a dissolution-diffusion-based passive loading mechanism. Accordingly, passive loading also occurred when drug and carrier particles were separated by a dialysis membrane. Knowledge of the loading mechanism allows optimizing the conditions for future passive loading studies and assessing the limitations of the method. Copyright © 2017 Elsevier B.V. All rights reserved.

BAG3 affects the nucleocytoplasmic shuttling of HSF1 upon heat stress

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

Jin, Young-Hee; Ahn, Sang-Gun; Kim, Soo-A., E-mail: ksooa@dongguk.ac.kr

2015-08-21

Bcl2-associated athoanogene (BAG) 3 is a member of the co-chaperone BAG family. It is induced by stressful stimuli such as heat shock and heavy metals, and it regulates cellular adaptive responses against stressful conditions. In this study, we identified a novel role for BAG3 in regulating the nuclear shuttling of HSF1 during heat stress. The expression level of BAG3 was induced by heat stress in HeLa cells. Interestingly, BAG3 rapidly translocalized to the nucleus upon heat stress. Immunoprecipitation assay showed that BAG3 interacts with HSF1 under normal and stressed conditions and co-translocalizes to the nucleus upon heat stress. We alsomore » demonstrated that BAG3 interacts with HSF1 via its BAG domain. Over-expression of BAG3 down-regulates the level of nuclear HSF1 by exporting it to the cytoplasm during the recovery period. Depletion of BAG3 using siRNA results in reduced nuclear HSF1 and decreased Hsp70 promoter activity. BAG3 in MEF(hsf1{sup −/−}) cells actively translocalizes to the nucleus upon heat stress suggesting that BAG3 plays a key role in the processing of the nucleocytoplasmic shuttling of HSF1 upon heat stress. - Highlights: • The expression level of BAG3 is induced by heat stress. • BAG3 translocates to the nucleus upon heat stress. • BAG3 interacts with HSF1 and co-localizes to the nucleus. • BAG3 is a key regulator for HSF1 nuclear shuttling.« less

49 CFR 178.520 - Standards for textile bags.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) 5L2 for a sift-proof textile bag; and (3) 5L3 for a water-resistant textile bag. (b) Construction... bag. (2) Bags, sift-proof, 5L2: The bag must be made sift-proof, by appropriate means, such as by the...

Breaking BAG: The Co-Chaperone BAG3 in Health and Disease.

PubMed

Behl, Christian

2016-08-01

Human BAG (Bcl-2-associated athanogene) proteins form a family of antiapoptotic proteins that currently consists of six members (BAG1-6) all sharing the BAG protein domain from which the name arises. Via this domain, BAG proteins bind to the heat shock protein 70 (Hsp70), thereby acting as a co-chaperone regulating the activity of Hsp70. In addition to their antiapoptotic activity, all human BAG proteins have distinct functions in health and disease, and BAG3 in particular is the focus of many investigations. BAG3 has a modular protein domain composition offering the possibility for manifold interactions with other proteins. Various BAG3 functions are implicated in disorders including cancer, myopathies, and neurodegeneration. The discovery of its role in selective autophagy and the description of BAG3-mediated selective macroautophagy as an adaptive mechanism to maintain cellular homeostasis, under stress as well as during aging, make BAG3 a highly interesting target for future pharmacological interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Non-local transport in turbulent MHD convection

NASA Technical Reports Server (NTRS)

Miesch, Mark; Brandenburg, Axel; Zweibel, Ellen; Toomre, Juri

1995-01-01

The nonlocal non-diffusive transport of passive scalars in turbulent magnetohydrodynamic (MHD) convection is investigated using transilient matrices. These matrices describe the probability that a tracer particle beginning at one position in a flow will be advected to another position after some time. A method for the calculation of these matrices from simulation data which involves following the trajectories of passive tracer particles and calculating their transport statistics, is presented. The method is applied to study the transport in several simulations of turbulent, rotating, three dimensional compressible, penetrative MDH convection. Transport coefficients and other diagnostics are used to quantify the transport, which is found to resemble advection more closely than diffusion. Some of the results are found to have direct relevance to other physical problems, such as the light element depletion in sun-type stars. The large kurtosis found for downward moving particles at the base of the convection zone implies several extreme events.

Diffuse shear wave imaging: toward passive elastography using low-frame rate spectral-domain optical coherence tomography

NASA Astrophysics Data System (ADS)

Nguyen, Thu-Mai; Zorgani, Ali; Lescanne, Maxime; Boccara, Claude; Fink, Mathias; Catheline, Stefan

2016-12-01

Optical coherence tomography (OCT) can map the stiffness of biological tissue by imaging mechanical perturbations (shear waves) propagating in the tissue. Most shear wave elastography (SWE) techniques rely on active shear sources to generate controlled displacements that are tracked at ultrafast imaging rates. Here, we propose a noise-correlation approach to retrieve stiffness information from the imaging of diffuse displacement fields using low-frame rate spectral-domain OCT. We demonstrated the method on tissue-mimicking phantoms and validated the results by comparison with classic ultrafast SWE. Then we investigated the in vivo feasibility on the eye of an anesthetized rat by applying noise correlation to naturally occurring displacements. The results suggest a great potential for passive elastography based on the detection of natural pulsatile motions using conventional spectral-domain OCT systems. This would facilitate the transfer of OCT-elastography to clinical practice, in particular, in ophthalmology or dermatology.

Diffuse shear wave imaging: toward passive elastography using low-frame rate spectral-domain optical coherence tomography.

PubMed

Nguyen, Thu-Mai; Zorgani, Ali; Lescanne, Maxime; Boccara, Claude; Fink, Mathias; Catheline, Stefan

2016-12-01

Optical coherence tomography (OCT) can map the stiffness of biological tissue by imaging mechanical perturbations (shear waves) propagating in the tissue. Most shear wave elastography (SWE) techniques rely on active shear sources to generate controlled displacements that are tracked at ultrafast imaging rates. Here, we propose a noise-correlation approach to retrieve stiffness information from the imaging of diffuse displacement fields using low-frame rate spectral-domain OCT. We demonstrated the method on tissue-mimicking phantoms and validated the results by comparison with classic ultrafast SWE. Then we investigated the in vivo feasibility on the eye of an anesthetized rat by applying noise correlation to naturally occurring displacements. The results suggest a great potential for passive elastography based on the detection of natural pulsatile motions using conventional spectral-domain OCT systems. This would facilitate the transfer of OCT-elastography to clinical practice, in particular, in ophthalmology or dermatology.

An efficient passive planar micromixer with ellipse-like micropillars for continuous mixing of human blood.

PubMed

Tran-Minh, Nhut; Dong, Tao; Karlsen, Frank

2014-10-01

In this paper, a passive planar micromixer with ellipse-like micropillars is proposed to operate in the laminar flow regime for high mixing efficiency. With a splitting and recombination (SAR) concept, the diffusion distance of the fluids in a micromixer with ellipse-like micropillars was decreased. Thus, space usage for micromixer of an automatic sample collection system is also minimized. Numerical simulation was conducted to evaluate the performance of proposed micromixer by solving the governing Navier-Stokes equation and convection-diffusion equation. With software (COMSOL 4.3) for computational fluid dynamics (CFD) we simulated the mixing of fluids in a micromixer with ellipse-like micropillars and basic T-type mixer in a laminar flow regime. The efficiency of the proposed micromixer is shown in numerical results and is verified by measurement results. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Enhanced Organic Solar Cell Stability through the Effective Blocking of Oxygen Diffusion using a Self-Passivating Metal Electrode.

PubMed

Lee, Hansol; Jo, Sae Byeok; Lee, Hyo Chan; Kim, Min; Sin, Dong Hun; Ko, Hyomin; Cho, Kilwon

2016-03-08

A new and simple strategy for enhancing the stability of organic solar cells (OSCs) was developed by using self-passivating metal top electrodes. Systematic investigations on O2 permeability of Al top electrodes revealed that the main pathways for oxidation-induced degradation could be greatly suppressed by simply controlling the nanoscale morphology of the Al electrode. The population of nanoscale pinholes among Al grains, which critically decided the diffusion of O2 molecules toward the Al-organic interfaces that are vulnerable to oxidation, was successfully regulated by rapidly depositing Al or promoting lateral growth among the Al grains, accompanied by increasing the deposition thickness. Our observations suggested that the stability of OSCs with conventional architectures might be greatly enhanced simply by controlling the fabrication conditions of the Al top electrode, without the aid of additional secondary treatments. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Use of a parallel artificial membrane system to evaluate passive absorption and elimination in small fish.

PubMed

Kwon, Jung-Hwan; Katz, Lynn E; Liljestrand, Howard M

2006-12-01

A parallel artificial lipid membrane system was developed to mimic passive mass transfer of hydrophobic organic chemicals in fish. In this physical model system, a membrane filter-supported lipid bilayer separates two aqueous phases that represent the external and internal aqueous environments of fish. To predict bioconcentration kinetics in small fish with this system, literature absorption and elimination rates were analyzed with an allometric diffusion model to quantify the mass transfer resistances in the aqueous and lipid phases of fish. The effect of the aqueous phase mass transfer resistance was controlled by adjusting stirring intensity to mimic bioconcentration rates in small fish. Twenty-three simple aromatic hydrocarbons were chosen as model compounds for purposes of evaluation. For most of the selected chemicals, literature absorption/elimination rates fall into the range predicted from measured membrane permeabilities and elimination rates of the selected chemicals determined by the diffusion model system.

RANS modeling of scalar dispersion from localized sources within a simplified urban-area model

NASA Astrophysics Data System (ADS)

Rossi, Riccardo; Capra, Stefano; Iaccarino, Gianluca

2011-11-01

The dispersion of a passive scalar downstream a localized source within a simplified urban-like geometry is examined by means of RANS scalar flux models. The computations are conducted under conditions of neutral stability and for three different incoming wind directions (0°, 45°, 90°) at a roughness Reynolds number of Ret = 391. A Reynolds stress transport model is used to close the flow governing equations whereas both the standard eddy-diffusivity closure and algebraic flux models are employed to close the transport equation for the passive scalar. The comparison with a DNS database shows improved reliability from algebraic scalar flux models towards predicting both the mean concentration and the plume structure. Since algebraic flux models do not increase substantially the computational effort, the results indicate that the use of tensorial-diffusivity can be promising tool for dispersion simulations for the urban environment.

High-Performance Quantum Dot Thin-Film Transistors with Environmentally Benign Surface Functionalization and Robust Defect Passivation.

PubMed

Jung, Su Min; Kang, Han Lim; Won, Jong Kook; Kim, JaeHyun; Hwang, ChaHwan; Ahn, KyungHan; Chung, In; Ju, Byeong-Kwon; Kim, Myung-Gil; Park, Sung Kyu

2018-01-31

The recent development of high-performance colloidal quantum dot (QD) thin-film transistors (TFTs) has been achieved with removal of surface ligand, defect passivation, and facile electronic doping. Here, we report on high-performance solution-processed CdSe QD-TFTs with an optimized surface functionalization and robust defect passivation via hydrazine-free metal chalcogenide (MCC) ligands. The underlying mechanism of the ligand effects on CdSe QDs has been studied with hydrazine-free ex situ reaction derived MCC ligands, such as Sn 2 S 6 4- , Sn 2 Se 6 4- , and In 2 Se 4 2- , to allow benign solution-process available. Furthermore, the defect passivation and remote n-type doping effects have been investigated by incorporating indium nanoparticles over the QD layer. Strong electronic coupling and solid defect passivation of QDs could be achieved by introducing electronically active MCC capping and thermal diffusion of the indium nanoparticles, respectively. It is also noteworthy that the diffused indium nanoparticles facilitate charge injection not only inter-QDs but also between source/drain electrodes and the QD semiconductors, significantly reducing contact resistance. With benign organic solvents, the Sn 2 S 6 4- , Sn 2 Se 6 4- , and In 2 Se 4 2- ligand based QD-TFTs exhibited field-effect mobilities exceeding 4.8, 12.0, and 44.2 cm 2 /(V s), respectively. The results reported here imply that the incorporation of MCC ligands and appropriate dopants provide a general route to high-performance, extremely stable solution-processed QD-based electronic devices with marginal toxicity, offering compatibility with standard complementary metal oxide semiconductor processing and large-scale on-chip device applications.

Thermo-activated nano-material for use in optical devices

NASA Astrophysics Data System (ADS)

Mias, Solon; Sudor, Jan; Camon, Henri

2007-05-01

In this paper we describe the use of thermo-activated PNIPAM nano-material in optical switching devices. In other publications, the PNIPAM is used either as a carrier for crystalline colloidal array self-assemblies or as micro-particles that serve as pigment bags. In this publication we use a simpler-to-fabricate pure PNIPAM solution in a semi-dilute regime. The PNIPAM devices produced are transparent at temperatures below a critical temperature of 32°C and become diffusing above this temperature. We show that at 632nm the transmission through the devices is about 75% in the transparent state while the additional attenuation achieved in the diffusing state is of the order of 38 dB. The experimental fall and rise times obtained are large (about 300ms and 5s respectively) due to the non-optimised thermal addressing scheme. In addition, spectral measurements taken in the infrared spectrum (700-1000nm) demonstrate that the cell response is flat over a large portion of the infrared spectrum in both the transparent and the diffusing states.

How hunter perceptions of wildlife regulations, agency trust, and satisfaction affect attitudes about duck bag limits

USGS Publications Warehouse

Schroeder, Susan A.; Fulton, David C.; Lawrence, Jeffrey S.; Cordts, Steven D.

2017-01-01

This study explored how factors, including the function of bag limits, agency trust, satisfaction, hunting participation, and demographics, related to opinions about duck bag limits. The results are from a survey of 2014 Minnesota resident waterfowl hunters. Analyses identified four dimensions of attitudes about functions of bag limits, including that they: (a) are descriptive in defining the acceptable number of ducks that can be bagged, (b) are injunctive in establishing how many ducks should be allowed to be bagged, (c) ensure fair opportunities for all hunters to bag ducks, and (d) reflect biological limitations to protect waterfowl populations. Descriptive and fairness functions of bag limits were related to opinions about bag limits, as were factors related to agency trust, satisfaction, ducks bagged, experience with more restrictive bag limits, hunter age, and hunting group membership. Agencies may increase support by building trust and emphasizing the descriptive and fairness functions of regulations.

78 FR 79391 - Foreign-Trade Zone (FTZ) 22-Chicago, Illinois, Notification of Proposed Production Activity...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-30

...; cable clamps; locks; belts; O-rings; sealing gaskets; support packages; filter bags; disposable bags; assembly bags; dust bags; maintenance packs; paper bags; dirt tube kits; paper adaptor bags; filters...; wire racks; bake pans; pizza pans; coffee water filters; water filters; base assemblies; dust cup...

WW domain of BAG3 is required for the induction of autophagy in glioma cells.

PubMed

Merabova, Nana; Sariyer, Ilker Kudret; Saribas, A Sami; Knezevic, Tijana; Gordon, Jennifer; Turco, M Caterina; Rosati, Alessandra; Weaver, Michael; Landry, Jacques; Khalili, Kamel

2015-04-01

Autophagy is an evolutionarily conserved, selective degradation pathway of cellular components that is important for cell homeostasis under healthy and pathologic conditions. Here we demonstrate that an increase in the level of BAG3 results in stimulation of autophagy in glioblastoma cells. BAG3 is a member of a co-chaperone family of proteins that associates with Hsp70 through a conserved BAG domain positioned near the C-terminus of the protein. Expression of BAG3 is induced by a variety of environmental changes that cause stress to cells. Our results show that BAG3 overexpression induces autophagy in glioma cells. Interestingly, inhibition of the proteasome caused an increase in BAG3 levels and induced autophagy. Further analysis using specific siRNA against BAG3 suggests that autophagic activation due to proteosomal inhibition is mediated by BAG3. Analyses of BAG3 domain mutants suggest that the WW domain of BAG3 is crucial for the induction of autophagy. BAG3 overexpression also increased the interaction between Bcl2 and Beclin-1, instead of disrupting them, suggesting that BAG3 induced autophagy is Beclin-1 independent. These observations reveal a novel role for the WW domain of BAG3 in the regulation of autophagy. © 2014 Wiley Periodicals, Inc.

WW domain of BAG3 is required for the induction of autophagy in glioma cells

PubMed Central

Merabova, Nana; Sariyer, Ilker Kudret; Saribas, A Sami; Knezevic, Tijana; Gordon, Jennifer; Weaver, Michael; Landry, Jacques; Khalili, Kamel

2015-01-01

Autophagy is an evolutionarily conserved, selective degradation pathway of cellular components that is important for cell homeostasis under healthy and pathologic conditions. Here we demonstrate that an increase in the level of BAG3 results in stimulation of autophagy in glioblastoma cells. BAG3 is a member of a co-chaperone family of proteins that associate with Hsp70 through a conserved BAG domain positioned near the C-terminus of the protein. Expression of BAG3 is induced by a variety of environmental changes that cause stress to cells. Our results show that BAG3 overexpression induces autophagy in glioma cells. Interestingly, inhibition of the proteasome caused an increase in BAG3 levels and induced autophagy. Further analysis using specific siRNA against BAG3 suggests that autophagic activation due to proteosomal inhibition is mediated by BAG3. Analyses of BAG3 domain mutants suggest that the WW domain of BAG3 is crucial for the induction of autophagy. BAG3 overexpression also increased the interaction between Bcl2 and Beclin-1, instead of disrupting them, suggesting that BAG3 induced autophagy is Beclin-1 independent. These observations reveal a novel role for the WW domain of BAG3 in the regulation of autophagy. PMID:25204229

Modelling passive diastolic mechanics with quantitative MRI of cardiac structure and function.

PubMed

Wang, Vicky Y; Lam, H I; Ennis, Daniel B; Cowan, Brett R; Young, Alistair A; Nash, Martyn P

2009-10-01

The majority of patients with clinically diagnosed heart failure have normal systolic pump function and are commonly categorized as suffering from diastolic heart failure. The left ventricle (LV) remodels its structure and function to adapt to pathophysiological changes in geometry and loading conditions, which in turn can alter the passive ventricular mechanics. In order to better understand passive ventricular mechanics, a LV finite element (FE) model was customized to geometric data segmented from in vivo tagged magnetic resonance images (MRI) data and myofibre orientation derived from ex vivo diffusion tensor MRI (DTMRI) of a canine heart using nonlinear finite element fitting techniques. MRI tissue tagging enables quantitative evaluation of cardiac mechanical function with high spatial and temporal resolution, whilst the direction of maximum water diffusion in each voxel of a DTMRI directly corresponds to the local myocardial fibre orientation. Due to differences in myocardial geometry between in vivo and ex vivo imaging, myofibre orientations were mapped into the geometric FE model using host mesh fitting (a free form deformation technique). Pressure recordings, temporally synchronized to the tagging data, were used as the loading constraints to simulate the LV deformation during diastole. Simulation of diastolic LV mechanics allowed us to estimate the stiffness of the passive LV myocardium based on kinematic data obtained from tagged MRI. Integrated physiological modelling of this kind will allow more insight into mechanics of the LV on an individualized basis, thereby improving our understanding of the underlying structural basis of mechanical dysfunction under pathological conditions.

Hydrogen passivation of titanium impurities in silicon: Effect of doping conditions

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

Santos, P.; Coutinho, J., E-mail: jose.coutinho@ua.pt; Torres, V. J. B.

2014-07-21

While the contamination of solar silicon by fast diffusing transition metals can be now limited through gettering, much attention has been drawn to the slow diffusing species, especially the early 3d and 4d elements. To some extent, hydrogen passivation has been successful in healing many deep centers, including transition metals in Si. Recent deep-level transient spectroscopy (DLTS) measurements concerning hydrogen passivation of Ti revealed the existence of at least four electrical levels related to Ti{sub i}H{sub n} in the upper-half of the gap. These findings challenge the existing models regarding both the current level assignment as well as the structure/speciesmore » involved in the defects. We revisit this problem by means of density functional calculations and find that progressive hydrogenation of interstitial Ti is thermodynamically stable in intrinsic and n-doped Si. Full passivation may not be possible to attain in p-type Si as Ti{sub i}H{sub 3} and Ti{sub i}H{sub 4} are metastable against dissociation and release of bond-centered protons. All DLTS electron traps are assigned, namely, E40′ to Ti{sub i}H(-/0), E170′ to Ti{sub i}H{sub 3}(0/+), E(270) to Ti{sub i}H{sub 2}(0/+), and E170 to Ti{sub i}H(0/+) transitions. Ti{sub i}H{sub 4} is confirmed to be electrically inert.« less

Acid Neutralizing Ability and Shear Bond Strength Using Orthodontic Adhesives Containing Three Different Types of Bioactive Glass.

PubMed

Yang, Song-Yi; Kim, Seong-Hwan; Choi, Se-Young; Kim, Kwang-Mahn

2016-02-24

The objective of the study was to compare the acid neutralizing ability and shear bond strength (SBS) of three different types of orthodontic adhesives containing bioactive glasses (BAGs). 45S5, 45S5F and S53P4 BAGs were prepared using the melting technique and ground to fine particles. Orthodontic adhesives containing three types of BAGs were prepared as follows: 52.5% 45S5 BAG + 17.5% glass (45S5_A); 61.25% 45S5 BAG + 8.75% glass (45S5_B); 52.5% 45S5F BAG + 17.5% glass (45S5F_A); 61.25% 45S5F BAG + 8.75% glass (45S5F_B); 52.5% S53P4 BAG + 17.5% glass (S53P4_A); 61.25% S53P4 BAG + 8.75% glass (S53P4_B); and 70.0% glass (BAG_0). To evaluate the acid neutralizing properties, specimens were immersed in lactic acid solution, and pH changes were measured. SBS was measured with a universal testing machine. For all of the BAG-containing adhesives, the one with 61.25% of BAG showed a significantly greater increase of pH than the one with 52.5% of BAG ( p < 0.05). Groups with 61.25% of BAG showed lower SBS than samples with 52.5% of BAG. 45S5F_A showed no significant difference of SBS compared to BAG_0 ( p > 0.05). The adhesive containing 61.25% of 45S5F BAG exhibited clinically acceptable SBS and acid neutralizing properties. Therefore, this composition is a suitable candidate to prevent white spot lesions during orthodontic treatment.

Differential gene expression analysis of ‘Chili’ (Pyrus bretschneideri) fruit pericarp with two types of bagging treatments

PubMed Central

Wang, Yuling; Zhang, Xinfu; Wang, Ran; Bai, Yingxin; Liu, Chenglian; Yuan, Yongbing; Yang, Yingjie; Yang, Shaolan

2017-01-01

Preharvest bagging is a simple, grower-friendly and safe physical protection technique commonly applied to many fruits, and the application of different fruit bags can have various effects. To explore the molecular mechanisms underlying the fruit quality effects of different bagging treatments, digital gene expression (DGE) profiling of bagged and unbagged ‘Chili’ (Pyrus bretschneideri Rehd.) pear pericarp during development was performed. Relative to unbagged fruit, a total of 3022 and 769 differentially expressed genes (DEGs) were detected in the polyethylene (PE)-bagged and non-woven fabric-bagged fruit, respectively. DEGs annotated as photosynthesis-antenna proteins and photosynthesis metabolism pathway were upregulated in non-woven fabric-bagged fruit but downregulated in the PE-bagged fruit. Non-woven fabric bagging inhibited lignin synthesis in ‘Chili’ pear pericarp by downregulating DEGs involved in phenylpropanoid biosynthesis; consequently, the fruit lenticels in non-woven fabric-bagged fruit were smaller than those in the other treatments. The results indicate that the non-woven fabric bagging method has a positive effect on the appearance of ‘Chili’ pear fruit but neither of the two bagging treatments is conducive to the accumulation of soluble sugar. PMID:28280542

Market diffusion and the effect of demonstrations: A study of Denver metro passive solar home program

NASA Astrophysics Data System (ADS)

Lilien, G. L.

1981-10-01

The reactions to and effects of the Denver metro passive solar home demonstration program, conducted in the spring of 1981 are reported. The program provides impetus to builders for incorporating passive solar designs in spec built homes and demonstrates those designs to prospective buyers to increase buyer receptivity. A pre-post exposure analysis of the effect of the program is reported and four separate groups of prospective new home buyers are studied. The first group heard publicity about and voluntarily visited a demonstration home. The second group saw the home, but was recruited to come to the side. The third group, also in Denver, did not see the site, but answered the same set of questions after receiving a description of and pictures of passive solar homes. The fourth group was a control group, similar to the third, but located in Kansas City.

Gallium-Doped Poly-Si:Ga/SiO 2 Passivated Emitters to n-Cz Wafers With iV oc >730 mV

DOE PAGES

Young, David L.; Lee, Benjamin G.; Fogel, Derek; ...

2017-09-26

Here, we form gallium-doped poly-Si:Ga/SiO 2 passivated contacts on n-type Czochralski (n-Cz) wafers using ion implantation of Ga and Ga-containing spin-on dopants. After annealing and passivation with Al 2O 3, the contacts exhibit i Voc values of >730 mV with corresponding Joe values of <5 fA/cm 2. These are among the best-reported values for p-type poly-Si/SiO 2 contacts. Secondary ion mass spectroscopic depth profile data show that, in contrast to B, Ga does not pileup at the SiO 2 interface in agreement with its known high diffusivity in SiO 2. This lack of Ga pileup may imply fewer dopant-related defectsmore » in the SiO 2, compared with B dopants, and account for the excellent passivation.« less

Coiled to diffuse: Brownian motion of a helical bacterium.

PubMed

Butenko, Alexander V; Mogilko, Emma; Amitai, Lee; Pokroy, Boaz; Sloutskin, Eli

2012-09-11

We employ real-time three-dimensional confocal microscopy to follow the Brownian motion of a fixed helically shaped Leptospira interrogans (LI) bacterium. We extract from our measurements the translational and the rotational diffusion coefficients of this bacterium. A simple theoretical model is suggested, perfectly reproducing the experimental diffusion coefficients, with no tunable parameters. An older theoretical model, where edge effects are neglected, dramatically underestimates the observed rates of translation. Interestingly, the coiling of LI increases its rotational diffusion coefficient by a factor of 5, compared to a (hypothetical) rectified bacterium of the same contour length. Moreover, the translational diffusion coefficients would have decreased by a factor of ~1.5, if LI were rectified. This suggests that the spiral shape of the spirochaete bacteria, in addition to being employed for their active twisting motion, may also increase the ability of these bacteria to explore the surrounding fluid by passive Brownian diffusion.

BAG3 induces the sequestration of proteasomal clients into cytoplasmic puncta

PubMed Central

Minoia, Melania; Boncoraglio, Alessandra; Vinet, Jonathan; Morelli, Federica F; Brunsting, Jeanette F; Poletti, Angelo; Krom, Sabine; Reits, Eric; Kampinga, Harm H; Carra, Serena

2014-01-01

Eukaryotic cells use autophagy and the ubiquitin–proteasome system as their major protein degradation pathways. Upon proteasomal impairment, cells switch to autophagy to ensure proper clearance of clients (the proteasome-to-autophagy switch). The HSPA8 and HSPA1A cochaperone BAG3 has been suggested to be involved in this switch. However, at present it is still unknown whether and to what extent BAG3 can indeed reroute proteasomal clients to the autophagosomal pathway. Here, we show that BAG3 induces the sequestration of ubiquitinated clients into cytoplasmic puncta colabeled with canonical autophagy linkers and markers. Following proteasome inhibition, BAG3 upregulation significantly contributes to the compensatory activation of autophagy and to the degradation of the (poly)ubiquitinated proteins. BAG3 binding to the ubiquitinated clients occurs through the BAG domain, in competition with BAG1, another BAG family member, that normally directs ubiquitinated clients to the proteasome. Therefore, we propose that following proteasome impairment, increasing the BAG3/BAG1 ratio ensures the “BAG-instructed proteasomal to autophagosomal switch and sorting” (BIPASS). PMID:25046115

BAG3 induces the sequestration of proteasomal clients into cytoplasmic puncta: implications for a proteasome-to-autophagy switch.

PubMed

Minoia, Melania; Boncoraglio, Alessandra; Vinet, Jonathan; Morelli, Federica F; Brunsting, Jeanette F; Poletti, Angelo; Krom, Sabine; Reits, Eric; Kampinga, Harm H; Carra, Serena

2014-09-01

Eukaryotic cells use autophagy and the ubiquitin-proteasome system as their major protein degradation pathways. Upon proteasomal impairment, cells switch to autophagy to ensure proper clearance of clients (the proteasome-to-autophagy switch). The HSPA8 and HSPA1A cochaperone BAG3 has been suggested to be involved in this switch. However, at present it is still unknown whether and to what extent BAG3 can indeed reroute proteasomal clients to the autophagosomal pathway. Here, we show that BAG3 induces the sequestration of ubiquitinated clients into cytoplasmic puncta colabeled with canonical autophagy linkers and markers. Following proteasome inhibition, BAG3 upregulation significantly contributes to the compensatory activation of autophagy and to the degradation of the (poly)ubiquitinated proteins. BAG3 binding to the ubiquitinated clients occurs through the BAG domain, in competition with BAG1, another BAG family member, that normally directs ubiquitinated clients to the proteasome. Therefore, we propose that following proteasome impairment, increasing the BAG3/BAG1 ratio ensures the "BAG-instructed proteasomal to autophagosomal switch and sorting" (BIPASS).

PASSIVE/DIFFUSIVE SAMPLERS FOR PESTICIDES IN RESIDENTIAL INDOOR AIR

EPA Science Inventory

Pesticides applied indoors vaporize from treated surfaces (e.g., carpets and baseboards) resulting in elevated air concentrations that may persist for long periods after applications. Estimating long-term respiratory exposures to pesticide vapors in residential indoor environme...

Reductions in deaths in frontal crashes among right front passengers in vehicles equipped with passenger air bags.

PubMed

Braver, E R; Ferguson, S A; Greene, M A; Lund, A K

1997-11-05

Virtually all new cars now are equipped with passenger air bags. Determining whether passenger air bags are saving lives is important, particularly because passenger air bags have caused some deaths among children and adults. To assess the effectiveness of passenger air bags in reducing the risk of death in frontal crashes for right front passengers. Air bags are designed to protect occupants in frontal crashes. Using Fatality Analysis Reporting System data for calendar years 1992 through 1995, the relative frequency of right front passenger deaths in frontal vs nonfrontal fatal crashes was compared for cars with dual air bags and for cars with driver-only air bags. Odds of right front passengers dying in frontal compared with nonfrontal fatal crashes were computed for 1992 through 1995 model year cars with dual air bags and for cars with driver-only air bags. Percentage reductions in right front passenger deaths in dual air bag vehicles were estimated. Right front passenger fatalities were 18% lower than expected in frontal crashes of cars with dual air bags and 11% lower in all crashes. An estimated 73 fewer than expected right front passengers died in 1992 through 1995 model cars with dual air bags during 1992 through 1995. The risk of frontal crash death for right front passengers in cars with dual air bags was reduced 14% among those reported to be using belts and 23% among belt nonusers. Children younger than 10 years in cars with dual air bags had a 34% increased risk of dying in frontal crashes. Passenger air bags were associated with substantial reductions in fatalities among right front passengers in frontal crashes. However, more children are being killed than are being saved by air bags. Immediate countermeasures to reduce the dangers of air bags to children and adults are suggested.

Effect of concentration boundary layers on passive solute flows in a system of two polymeric membranes positioned in vertical planes.

PubMed

Slezak, Andrzej; Jasik-Slezak, Jolanta; Dworecki, Kazimierz

2003-01-01

The results of studies of influence of concentration boundary layers on passive diffusive transport in a double-membrane osmo-diffusive cell, containing a series of two (Ml and M(r)) vertically positioned, flat, microporous and symmetric polymer membranes (Nephrophane and Cellulose IMP-1) are presented in this paper. The membranes separated three compartments (l, m, r) containing binary, heterogeneous and non-ionic solutions (aqueous solutions of glucose or ethanol) or ternary non-electrolyte solutions (glucose solutions in 0.75 mol.l-1 solution of ethanol or ethanol solutions in 0.1 mol.l-1 aqueous solution of glucose). Solution concentrations fulfilled the condition C(k)l > C(k)m > C(k)r. The intermembrane compartment (m) was an infinitesimal solution layer. The volume of the m compartment and the volumes of the external (l and r) compartments fulfilled the condition Vl = Vr approximately 170 Vm. The tests were performed for configurations A and B of a double-membrane osmo-diffusive cell. In configuration A, the solution was located behind the M(r) membrane, and water was placed behind the Ml membrane, while in configuration B this sequence was reversed. The results obtained during experiment were interpreted in the categories of convective instability, which increased the value of diffusive permeability coefficient of the system: concentration boundary layer/membrane/concentration boundary layer.

Study of the suitability of DUO plastic bags for the storage of dynamites.

PubMed

Sáiz, Jorge; Ferrando, José-Luis; Atoche, Juan-Carlos; García-Ruiz, Carmen

2013-10-10

A comparative study on the retentiveness of two plastic bags (DUO and Royal Pack) has been carried out by gas chromatography with mass spectrometry detection. Two types of dynamites were packed in both plastic bags. The bags were placed into glass jars and headspace analyses were performed over 11 weeks to detect whether the volatile constituents of the dynamites were released from the bags. DUO plastic bags showed much better retentiveness than Royal Pack plastic bags. Ethylene glycol dinitrate (EGDN) was quickly detected in the headspace of the glass jars containing Royal Pack plastic bags after 1 week of storage. On the contrary, only a weak signal of EGDN, which was not detectable in the total ion chromatogram, was detected after 11 weeks of storage. Moreover, DUO plastic bags have shown less background signals than the Royal Pack bags, being the former bags much more suitable for the storage of dynamites. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Ammonia excretion and urea handling by fish gills: present understanding and future research challenges.

PubMed

Wilkie, Michael Patrick

2002-08-01

In fresh water fishes, ammonia is excreted across the branchial epithelium via passive NH(3) diffusion. This NH(3) is subsequently trapped as NH(4)(+) in an acidic unstirred boundary layer lying next to the gill, which maintains the blood-to-gill water NH(3) partial pressure gradient. Whole animal, in situ, ultrastructural and molecular approaches suggest that boundary layer acidification results from the hydration of CO(2) in the expired gill water, and to a lesser extent H(+) excretion mediated by apical H(+)-ATPases. Boundary layer acidification is insignificant in highly buffered sea water, where ammonia excretion proceeds via NH(3) diffusion, as well as passive NH(4)(+) diffusion due to the greater ionic permeability of marine fish gills. Although Na(+)/H(+) exchangers (NHE) have been isolated in marine fish gills, possible Na(+)/NH(4)(+) exchange via these proteins awaits evaluation using modern electrophysiological and molecular techniques. Although urea excretion (J(Urea)) was thought to be via passive diffusion, it is now clear that branchial urea handling requires specialized urea transporters. Four urea transporters have been cloned in fishes, including the shark kidney urea transporter (shUT), which is a facilitated urea transporter similar to the mammalian renal UT-A2 transporter. Another urea transporter, characterized but not yet cloned, is the basolateral, Na(+) dependent urea antiporter of the dogfish gill, which is essential for urea retention in ureosmotic elasmobranchs. In ureotelic teleosts such as the Lake Magadi tilapia and the gulf toadfish, the cloned mtUT and tUT are facilitated urea transporters involved in J(Urea). A basolateral urea transporter recently cloned from the gill of the Japanese eel (eUT) may actually be important for urea retention during salt water acclimation. A multi-faceted approach, incorporating whole animal, histological, biochemical, pharmacological, and molecular techniques is required to learn more about the location, mechanism of action, and functional significance of urea transporters in fishes. Copyright 2002 Wiley-Liss, Inc.

42 CFR 84.88 - Breathing bag test.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Apparatus § 84.88 Breathing bag test. (a) Breathing bags will be tested in an air atmosphere saturated with... Institute upon request. (d) The air within the bag(s) shall not contain more than 100 parts per million of... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing bag test. 84.88 Section 84.88 Public...

Recombination reduction at the c-Si/RCA oxide interface through Ar-H2 plasma treatment

NASA Astrophysics Data System (ADS)

Landheer, Kees; Bronsveld, Paula C. P.; Poulios, Ioannis; Tichelaar, Frans D.; Kaiser, Monja; Schropp, Ruud E. I.; Rath, Jatin K.

2017-02-01

An Ar-H2 plasma treatment was applied on an ultrathin RCA oxide to create well-passivated silicon wafers with symmetric c-Si/SiOx:H/a-Si:H passivation layer stacks. The effective lifetime of these samples increased from 10 μs to 4 ms after annealing at 200 °C through Ar-H2 plasma treatment of the oxide. The results indicate that the plasma treatment can modify the RCA oxide and this enables atomic hydrogen diffusion at low annealing temperature, leading to a well passivated c-Si/SiOx:H interface. This might provide new possibilities to use wet chemical oxides in c-Si solar cells, for example as tunnel contacts.

Catastrophic failures of freezing bags for cellular therapy products: description, cause, and consequences.

PubMed

Khuu, H M; Cowley, H; David-Ocampo, V; Carter, C S; Kasten-Sportes, C; Wayne, A S; Solomon, S R; Bishop, M R; Childs, R M; Read, E J

2002-01-01

Container integrity is critical for maintaining sterility of cryopreserved cellular therapy products. We investigated a series of catastrophic bag failures, first noticed in early 2001. Process records were reviewed for all PBPC and lymphocyte products cryopreserved in bags from January 2000 through April 2002. Patient charts were also reviewed. One thousand two hundred and four bags were removed from storage for infusion to 261 patients. All products had been cryopreserved in Cryocyte poly(ethylene co-vinyl acetate) (EVA) bags in either 10% DMSO or 5% DMSO and 6% pentastarch. Product volumes were 25-75 mL, and bags were stored with overwrap bags in a liquid nitrogen tank. From January 2000 to April 2001, failure occurred in 10 of 599 (1.7%) bags. From May 2001 to April 2002, 58 of 605 (9.6%) bags failed, typically with extensive fractures that were visible before thaw. Of the 58 that failed, 24 were salvaged by aseptic methods and infused to patients under antibiotic coverage; 10 of those 24 (42%) had positive bacterial cultures. Bag failures were not related to product type, cryoprotectant solution, liquid versus vapor storage, or freezer location. Failures were linked to use of four Cryocyte bag lots manufactured in 2000 and 2001. After replacing these lots with a 1999 Cryocyte lot and with KryoSafe polyfluoroethylene polyfluoropropylene (FEP) bags, no more failures occurred in 75 and 102 bags, respectively, thawed through April 2002. High rates of bag failure were associated with four Cryocyte bag lots. No serious adverse patient effects occurred, but bag failures led to microbial contamination, increased product preparation time, increased antibiotic use, and increased resource expenditure to replace products.

Design and development of pressure and repressurization purge system for reusable space shuttle multilayer insulation system

NASA Technical Reports Server (NTRS)

1972-01-01

The experimental determination of purge bag materials properties, development of purge bag manufacturing techniques, experimental evaluation of a subscale purge bag under simulated operating conditions and the experimental evaluation of the purge pin concept for MLI purging are discussed. The basic purge bag material, epoxy fiberglass bounded by skins of FEP Teflon, showed no significant permeability to helium flow under normal operating conditions. Purge bag small scale manufacturing tests were conducted to develop tooling and fabrication techniques for use in full scale bag manufacture. A purge bag material layup technique was developed whereby the two plys of epoxy fiberglass enclosed between skins of FEP Teflon are vacuum bag cured in an oven in a single operation. The material is cured on a tool with the shape of a purge bag half. Plastic tooling was selected for use in bag fabrication. A model purge bag 0.6 m in diameter was fabricated and subjected to a series of structural and environmental tests simulating various flight type environments. Pressure cycling tests at high (450 K) and low (200 K) temperature as well as acoustic loading tests were performed. The purge bag concept proved to be structurally sound and was used for the full scale bag detailed design model.

BAG3 affects the nucleocytoplasmic shuttling of HSF1 upon heat stress.

PubMed

Jin, Young-Hee; Ahn, Sang-Gun; Kim, Soo-A

2015-08-21

Bcl2-associated athoanogene (BAG) 3 is a member of the co-chaperone BAG family. It is induced by stressful stimuli such as heat shock and heavy metals, and it regulates cellular adaptive responses against stressful conditions. In this study, we identified a novel role for BAG3 in regulating the nuclear shuttling of HSF1 during heat stress. The expression level of BAG3 was induced by heat stress in HeLa cells. Interestingly, BAG3 rapidly translocalized to the nucleus upon heat stress. Immunoprecipitation assay showed that BAG3 interacts with HSF1 under normal and stressed conditions and co-translocalizes to the nucleus upon heat stress. We also demonstrated that BAG3 interacts with HSF1 via its BAG domain. Over-expression of BAG3 down-regulates the level of nuclear HSF1 by exporting it to the cytoplasm during the recovery period. Depletion of BAG3 using siRNA results in reduced nuclear HSF1 and decreased Hsp70 promoter activity. BAG3 in MEF(hsf1(-/-)) cells actively translocalizes to the nucleus upon heat stress suggesting that BAG3 plays a key role in the processing of the nucleocytoplasmic shuttling of HSF1 upon heat stress. Copyright © 2015 Elsevier Inc. All rights reserved.

Generation and precise control of dynamic biochemical gradients for cellular assays

NASA Astrophysics Data System (ADS)

Saka, Yasushi; MacPherson, Murray; Giuraniuc, Claudiu V.

2017-03-01

Spatial gradients of diffusible signalling molecules play crucial roles in controlling diverse cellular behaviour such as cell differentiation, tissue patterning and chemotaxis. In this paper, we report the design and testing of a microfluidic device for diffusion-based gradient generation for cellular assays. A unique channel design of the device eliminates cross-flow between the source and sink channels, thereby stabilizing gradients by passive diffusion. The platform also enables quick and flexible control of chemical concentration that makes highly dynamic gradients in diffusion chambers. A model with the first approximation of diffusion and surface adsorption of molecules recapitulates the experimentally observed gradients. Budding yeast cells cultured in a gradient of a chemical inducer expressed a reporter fluorescence protein in a concentration-dependent manner. This microfluidic platform serves as a versatile prototype applicable to a broad range of biomedical investigations.

Renormalization group analysis of anisotropic diffusion in turbulent shear flows

NASA Technical Reports Server (NTRS)

Rubinstein, Robert; Barton, J. Michael

1991-01-01

The renormalization group is applied to compute anisotropic corrections to the scalar eddy diffusivity representation of turbulent diffusion of a passive scalar. The corrections are linear in the mean velocity gradients. All model constants are computed theoretically. A form of the theory valid at arbitrary Reynolds number is derived. The theory applies only when convection of the velocity-scalar correlation can be neglected. A ratio of diffusivity components, found experimentally to have a nearly constant value in a variety of shear flows, is computed theoretically for flows in a certain state of equilibrium. The theoretical value is well within the fairly narrow range of experimentally observed values. Theoretical predictions of this diffusivity ratio are also compared with data from experiments and direct numerical simulations of homogeneous shear flows with constant velocity and scalar gradients.

Field evaluation of the long-lasting treated storage bag, deltamethrin-incorporated (ZeroFly® Storage Bag) as a barrier to insect pest infestation

USDA-ARS?s Scientific Manuscript database

The deltamethrin-incorporated polypropylene (PP) bag, ZeroFly® Storage Bag, is a new technology to reduce postharvest losses caused by stored-product insect pests. ZeroFly bags filled with untreated maize were compared to PP bags filled with maize treated with Betallic Super (80 g pirimiphos-methyl ...

Investigating axial diffusion in cylindrical pores using confocal single-particle fluorescence correlation spectroscopy.

PubMed

Chen, Fang; Neupane, Bhanu; Li, Peiyuan; Su, Wei; Wang, Gufeng

2016-08-01

We explored the feasibility of using confocal fluorescence correlation spectroscopy to study small nanoparticle diffusion in hundred-nanometer-sized cylindrical pores. By modeling single particle diffusion in tube-like confined three-dimensional space aligned parallel to the confocal optical axis, we showed that two diffusion dynamics can be observed in both original intensity traces and the autocorrelation functions (ACFs): the confined two-dimensional lateral diffusion and the unconfined one-dimensional (1D) axial diffusion. The separation of the axial and confined lateral diffusion dynamics provides an opportunity to study diffusions in different dimensions separately. We further experimentally studied 45 nm carboxylated polystyrene particles diffusing in 300 nm alumina pores. The experimental data showed consistency with the simulation. To extract the accurate axial diffusion coefficient, we found that a 1D diffusion model with a Lorentzian axial collection profile needs to be used to analyze the experimental ACFs. The diffusion of the 45 nm nanoparticles in polyethyleneglycol-passivated 300 nm pores slowed down by a factor of ∼2, which can be satisfactorily explained by hydrodynamic frictions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bag-1 and Bcl-2 gene transfer in malignant glioma: modulation of cell cycle regulation and apoptosis.

PubMed

Roth, W; Grimmel, C; Rieger, L; Strik, H; Takayama, S; Krajewski, S; Meyermann, R; Dichgans, J; Reed, J C; Weller, M

2000-04-01

Bag-1 is a heat shock 70 kDa (Hsp70)-binding protein that can collaborate with Bcl-2 in suppressing apoptosis under some conditions. Here, we report that 11 of 12 human glioma cell lines express Bag-1 protein in vitro. Moreover, 15 of 19 human glioblastomas expressed Bag-1 as assessed by immunohistochemistry in primary tumor specimens. To examine the biological effects of Bag-1 in glioma cells, we expressed Bag-1 or Bcl-2 transgenes in 2 human malignant glioma cell lines, LN-18 and LN-229. Bag-1 significantly slowed glioma cell growth and reduced clonogenicity of both cell lines in vitro. Coexpressed Bcl-2 abrogated these effects of Bag-1. Intracranial LN-229 glioma xenografts implanted into nude mice revealed a substantial growth advantage afforded by Bcl-2. Bag-1 had no such effect, either in the absence or presence of Bcl-2. Upon serum starvation in vitro, Bcl-2 prevented cell death whereas Bag-1 did not. Both Bcl-2 and Bag-1 slowed proliferation of serum-starved cells when expressed alone. Importantly, coexpression of Bcl-2 and Bag-1 provided a distinct growth advantage under conditions of serum starvation that is probably the result of (i) the death-preventing activity of Bcl-2 and (ii) the property of Bag-1 to overcome a Bcl-2-mediated enhancement of exit from the cell cycle. In contrast to these Bcl-2/Bag-1 interactions observed under serum starvation conditions, Bag-1 did not further enhance the strong protection from staurosporine-, CD95 (Fas/Apo1) ligand-, Apo2 ligand (TRAIL)- or chemotherapeutic drug-induced apoptosis afforded by Bcl-2. Taken together, these results indicate a role for Bag-1/Bcl-2 interactions in providing a survival advantage to cancer cells in a deprived microenvironment that may be characteristic of ischemic/hypoxic tumors such as human glioblastoma multiforme, and suggest that Bcl-2/Bag-1 interactions also modulate cell proliferation.

Passive Diffusion as a Mechanism Underlying Ribbon Synapse Vesicle Release and Resupply

PubMed Central

Graydon, Cole W.; Zhang, Jun; Oesch, Nicholas W.; Sousa, Alioscka A.; Leapman, Richard D.

2014-01-01

Synaptic ribbons are presynaptic protein structures found at many synapses that convey graded, “analog” sensory signals in the visual, auditory, and vestibular pathways. Ribbons, typically anchored to the presynaptic membrane and surrounded by tethered synaptic vesicles, are thought to regulate or facilitate vesicle delivery to the presynaptic membrane. No direct evidence exists, however, to indicate how vesicles interact with the ribbon or, once attached, move along the ribbon's surface to reach the presynaptic release sites at its base. To address these questions, we have created, validated, and tested a passive vesicle diffusion model of retinal rod bipolar cell ribbon synapses. We used axial (bright-field) electron tomography in the scanning transmission electron microscopy to obtain 3D structures of rat rod bipolar cell terminals in 1-μm-thick sections of retinal tissue at an isotropic spatial resolution of ∼3 nm. The resulting structures were then incorporated with previously published estimates of vesicle diffusion dynamics into numerical simulations that accurately reproduced electrophysiologically measured vesicle release/replenishment rates and vesicle pool sizes. The simulations suggest that, under physiologically realistic conditions, diffusion of vesicles crowded on the ribbon surface gives rise to a flow field that enhances delivery of vesicles to the presynaptic membrane without requiring an active transport mechanism. Numerical simulations of ribbon–vesicle interactions predict that transient binding and unbinding of multiple tethers to each synaptic vesicle may achieve sufficiently tight association of vesicles to the ribbon while permitting the fast diffusion along the ribbon that is required to sustain high release rates. PMID:24990916

Passive diffusion as a mechanism underlying ribbon synapse vesicle release and resupply.

PubMed

Graydon, Cole W; Zhang, Jun; Oesch, Nicholas W; Sousa, Alioscka A; Leapman, Richard D; Diamond, Jeffrey S

2014-07-02

Synaptic ribbons are presynaptic protein structures found at many synapses that convey graded, "analog" sensory signals in the visual, auditory, and vestibular pathways. Ribbons, typically anchored to the presynaptic membrane and surrounded by tethered synaptic vesicles, are thought to regulate or facilitate vesicle delivery to the presynaptic membrane. No direct evidence exists, however, to indicate how vesicles interact with the ribbon or, once attached, move along the ribbon's surface to reach the presynaptic release sites at its base. To address these questions, we have created, validated, and tested a passive vesicle diffusion model of retinal rod bipolar cell ribbon synapses. We used axial (bright-field) electron tomography in the scanning transmission electron microscopy to obtain 3D structures of rat rod bipolar cell terminals in 1-μm-thick sections of retinal tissue at an isotropic spatial resolution of ∼3 nm. The resulting structures were then incorporated with previously published estimates of vesicle diffusion dynamics into numerical simulations that accurately reproduced electrophysiologically measured vesicle release/replenishment rates and vesicle pool sizes. The simulations suggest that, under physiologically realistic conditions, diffusion of vesicles crowded on the ribbon surface gives rise to a flow field that enhances delivery of vesicles to the presynaptic membrane without requiring an active transport mechanism. Numerical simulations of ribbon-vesicle interactions predict that transient binding and unbinding of multiple tethers to each synaptic vesicle may achieve sufficiently tight association of vesicles to the ribbon while permitting the fast diffusion along the ribbon that is required to sustain high release rates. Copyright © 2014 the authors 0270-6474/14/348948-15$15.00/0.

Colloidal transport through trap arrays controlled by active microswimmers

NASA Astrophysics Data System (ADS)

Yang, Wen; Misko, Vyacheslav R.; Marchesoni, Fabio; Nori, Franco

2018-07-01

We investigate the dynamics of a binary mixture consisting of active and passive colloidal particles diffusing in a 2D array of truncated harmonic wells, or traps. We explore the possibility of using a small fraction of active particles to manipulate a much larger fraction of passive particles, for instance, to confine them in or extract them from the traps. The results of our study have potential application in biology and medical sciences, for example, to remove dead cells or undesired contaminants from biological systems by means of self-propelled nano-robots.

Bcl-2–associated athanogene 3 protects the heart from ischemia/reperfusion injury

PubMed Central

Su, Feifei; Myers, Valerie D.; Knezevic, Tijana; Wang, JuFang; Gao, Erhe; Madesh, Muniswamy; Tahrir, Farzaneh G.; Gupta, Manish K.; Gordon, Jennifer; Rabinowitz, Joseph; Tilley, Douglas G.; Khalili, Kamel; Cheung, Joseph Y.

2016-01-01

Bcl-2–associated athanogene 3 (BAG3) is an evolutionarily conserved protein expressed at high levels in the heart and the vasculature and in many cancers. While altered BAG3 expression has been associated with cardiac dysfunction, its role in ischemia/reperfusion (I/R) is unknown. To test the hypothesis that BAG3 protects the heart from reperfusion injury, in vivo cardiac function was measured in hearts infected with either recombinant adeno-associated virus serotype 9–expressing (rAAV9-expressing) BAG3 or GFP and subjected to I/R. To elucidate molecular mechanisms by which BAG3 protects against I/R injury, neonatal mouse ventricular cardiomyocytes (NMVCs) in which BAG3 levels were modified by adenovirus expressing (Ad-expressing) BAG3 or siBAG3 were exposed to hypoxia/reoxygenation (H/R). H/R significantly reduced NMVC BAG3 levels, which were associated with enhanced expression of apoptosis markers, decreased expression of autophagy markers, and reduced autophagy flux. The deleterious effects of H/R on apoptosis and autophagy were recapitulated by knockdown of BAG3 with Ad-siBAG3 and were rescued by Ad-BAG3. In vivo, treatment of mice with rAAV9-BAG3 prior to I/R significantly decreased infarct size and improved left ventricular function when compared with mice receiving rAAV9-GFP and improved markers of autophagy and apoptosis. These findings suggest that BAG3 may provide a therapeutic target in patients undergoing reperfusion after myocardial infarction. PMID:27882354

Bcl-2-associated athanogene 3 (BAG3) is an enhancer of small heat shock protein turnover via activation of autophagy in the heart.

PubMed

Inomata, Yui; Nagasaka, Shouta; Miyate, Kazuki; Goto, Yuta; Hino, Chizuru; Toukairin, Chihiro; Higashio, Rieko; Ishida, Kinji; Saino, Tomoyuki; Hirose, Masamichi; Tsumura, Hideki; Sanbe, Atsushi

2018-02-19

Bcl-2-associated athanogene 3 (BAG3) is strongly expressed in both cardiac and skeletal muscle. A recent study showed that BAG3 may play a protective role in muscles. Little is known, however, regarding the detailed role of BAG3 in cardiac muscle. To better understand the functional role of cardiac BAG3 in the heart, we generated transgenic (TG) mice that overexpress BAG3. A decrease in fractional shortening, and the induction of cardiac atrial natriuretic peptide, were observed in BAG3 TG mice. Moreover, a marked reduction in the protein level of small HSPs was detected in BAG3 TG mouse hearts. We analyzed the cardiac small HSP levels when either the ubiquitin-proteasome system (UPS) or the autophagy system (AS) was inhibited in BAG3 TG mice. The protein turnovers of small HSPs by the AS were activated in BAG3 TG mouse hearts. Thus, BAG3 is critical for the protein turnover of small HSPs via activation of autophagy in the heart. Copyright © 2018 Elsevier Inc. All rights reserved.

Bagworm bags as portable armour against invertebrate predators.

PubMed

Sugiura, Shinji

2016-01-01

Some animals have evolved the use of environmental materials as "portable armour" against natural enemies. Portable bags that bagworm larvae (Lepidoptera: Psychidae) construct using their own silk and plant parts are generally believed to play an important role as a physical barrier against natural enemies. However, no experimental studies have tested the importance of bags as portable armour against predators. To clarify the defensive function, I studied the bagworm Eumeta minuscula and a potential predator Calosoma maximoviczi (Coleoptera: Carabidae). Under laboratory conditions, all bagworm larvae were attacked by carabid adults, but successfully defended themselves against the predators' mandibles using their own bags. The portable bags, which are composed mainly of host plant twigs, may function as a physical barrier against predator mandibles. To test this hypothesis, I removed the twig bags and replaced some with herb leaf bags; all bag-removed larvae were easily caught and predated by carabids, while all bag-replaced larvae could successfully defend themselves against carabid attacks. Therefore, various types of portable bags can protect bagworm larvae from carabid attacks. This is the first study to test the defensive function of bagworm portable bags against invertebrate predators.

BAG3 regulates contractility and Ca(2+) homeostasis in adult mouse ventricular myocytes.

PubMed

Feldman, Arthur M; Gordon, Jennifer; Wang, JuFang; Song, Jianliang; Zhang, Xue-Qian; Myers, Valerie D; Tilley, Douglas G; Gao, Erhe; Hoffman, Nicholas E; Tomar, Dhanendra; Madesh, Muniswamy; Rabinowitz, Joseph; Koch, Walter J; Su, Feifei; Khalili, Kamel; Cheung, Joseph Y

2016-03-01

Bcl2-associated athanogene 3 (BAG3) is a 575 amino acid anti-apoptotic protein that is constitutively expressed in the heart. BAG3 mutations, including mutations leading to loss of protein, are associated with familial cardiomyopathy. Furthermore, BAG3 levels have been found to be reduced in end-stage non-familial failing myocardium. In contrast to neonatal myocytes in which BAG3 is found in the cytoplasm and involved in protein quality control and apoptosis, in adult mouse left ventricular (LV) myocytes BAG3 co-localized with Na(+)-K(+)-ATPase and L-type Ca(2+) channels in the sarcolemma and t-tubules. BAG3 co-immunoprecipitated with β1-adrenergic receptor, L-type Ca(2+) channels and phospholemman. To simulate decreased BAG3 protein levels observed in human heart failure, we targeted BAG3 by shRNA (shBAG3) in adult LV myocytes. Reducing BAG3 by 55% resulted in reduced contraction and [Ca(2+)]i transient amplitudes in LV myocytes stimulated with isoproterenol. L-type Ca(2+) current (ICa) and sarcoplasmic reticulum (SR) Ca(2+) content but not Na(+)/Ca(2+) exchange current (INaCa) or SR Ca(2+) uptake were reduced in isoproterenol-treated shBAG3 myocytes. Forskolin or dibutyryl cAMP restored ICa amplitude in shBAG3 myocytes to that observed in WT myocytes, consistent with BAG3 having effects upstream and at the level of the receptor. Resting membrane potential and action potential amplitude were unaffected but APD50 and APD90 were prolonged in shBAG3 myocytes. Protein levels of Ca(2+) entry molecules and other important excitation-contraction proteins were unchanged in myocytes with lower BAG3. Our findings that BAG3 is localized at the sarcolemma and t-tubules while modulating myocyte contraction and action potential duration through specific interaction with the β1-adrenergic receptor and L-type Ca(2+) channel provide novel insight into the role of BAG3 in cardiomyopathies and increased arrhythmia risks in heart failure. Copyright © 2016 Elsevier Ltd. All rights reserved.

BAG3 regulates contractility and Ca2+ homeostasis in adult mouse ventricular myocytes

PubMed Central

Feldman, Arthur M.; Gordon, Jennifer; Wang, JuFang; Song, Jianliang; Zhang, Xue-Qian; Myers, Valerie D.; Tilley, Douglas G.; Gao, Erhe; Hoffman, Nicholas E.; Tomar, Dhanendra; Madesh, Muniswamy; Rabinowitz, Joseph; Koch, Walter J.; Su, Feifei; Khalili, Kamel; Cheung, Joseph Y.

2016-01-01

Bcl2-associated athanogene 3 (BAG3) is a 575 amino acid anti-apoptotic protein that is constitutively expressed in the heart. BAG3 mutations, including mutations leading to loss of protein, are associated with familial cardiomyopathy. Furthermore, BAG3 levels have been found to be reduced in end-stage non-familial failing myocardium. In contrast to neonatal myocytes in which BAG3 is found in the cytoplasm and involved in protein quality control and apoptosis, in adult mouse left ventricular (LV) myocytes BAG3 co-localized with Na+-K+-ATPase and L-type Ca2+ channels in the sarcolemma and t-tubules. BAG3 co-immunoprecipitated with β1-adrenergic receptor, L-type Ca2+ channels and phospholemman. To simulate decreased BAG3 protein levels observed in human heart failure, we targeted BAG3 by shRNA (shBAG3) in adult LV myocytes. Reducing BAG3 by 55% resulted in reduced contraction and [Ca2+]i transient amplitudes in LV myocytes stimulated with isoproterenol. L-type Ca2+ current (ICa) and sarcoplasmic reticulum (SR) Ca2+ content but not Na+/Ca2+ exchange current (INaCa) or SR Ca2+ uptake were reduced in isoproterenol-treated shBAG3 myocytes. Forskolin or dibutyrl cAMP restored ICa amplitude in shBAG3 myocytes to that observed in WT myocytes, consistent with BAG3 having effects upstream and at the level of the receptor. Resting membrane potential and action potential amplitude were unaffected but APD50 and APD90 were prolonged in shBAG3 myocytes. Protein levels of Ca2+ entry molecules and other important excitation-contraction proteins were unchanged in myocytes with lower BAG3. Our findings that BAG3 is localized at the sarcolemma and t-tubules while modulating myocyte contraction and action potential duration through specific interaction with the β1-adrenergic receptor and L-type Ca2+ channel provide novel insight into the role of BAG3 in cardiomyopathies and increased arrhythmia risks in heart failure. PMID:26796036

Confocal imaging to quantify passive transport across biomimetic lipid membranes.

PubMed

Li, Su; Hu, Peichi; Malmstadt, Noah

2010-09-15

The ability of a molecule to pass through the plasma membrane without the aid of any active cellular mechanisms is central to that molecule's pharmaceutical characteristics. Passive transport has been understood in the context of Overton's rule, which states that more lipophilic molecules cross membrane lipid bilayers more readily. Existing techniques for measuring passive transport lack reproducibility and are hampered by the presence of an unstirred layer (USL) that dominates transport across the bilayer. This report describes assays based on spinning-disk confocal microscopy (SDCM) of giant unilamellar vesicles (GUVs) that allow for the detailed investigation of passive transport processes and mechanisms. This approach allows the concentration field to be directly observed, allowing membrane permeability to be determined easily from the transient concentration profile data. A series of molecules of increasing hydrophilicity was constructed, and the transport of these molecules into GUVs was observed. The observed permeability trend is consistent with Overton's rule. However, the values measured depart from the simple partition-diffusion proportionality model of passive transport. This technique is easy to implement and has great promise as an approach to measure membrane transport. It is optimally suited to precise quantitative measurements of the dependence of passive transport on membrane properties.

Mesoscale Elucidation of Surface Passivation in the Li–Sulfur Battery Cathode

DOE PAGES

Liu, Zhixiao; Mukherjee, Partha P.

2017-01-23

We report the cathode surface passivation caused by Li 2S precipitation adversely affects the performance of lithium-sulfur (Li-S) batteries. Li 2S precipitation is a complicated mesoscale process involving adsorption, desorption and diffusion kinetics, which are affected profoundly by the reactant concentration and operating temperature. In this work, a mesoscale interfacial model is presented to study the growth of Li 2S film on carbon cathode surface. Li 2S film growth experiences nucleation, isolated Li 2S island growth and island coalescence. The slow adsorption rate at small S 2- concentration inhibits the formation of nucleation seeds and the lateral growth of Limore » 2S islands, which deters surface passivation. An appropriate operating temperature, especially in the medium-to-high temperature range, can also defer surface passivation. Fewer Li 2S nucleation seeds form in such an operating temperature range, which facilitates heterogeneous growth and thereby inhibits the lateral growth of the Li 2S film, which may also result in reduced surface passivation. Finally, the high specific surface area of the cathode microstructure is expected to mitigate the surface passivation.« less

A new possible picture of the hadron structure

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

Pokrovsky, Yury E.

A new chiral-scale invariant version of the bag model (CSB) is developed and applied to calculations of masses and radii for single bag states. The mass formula of the CSB model contains no free parameters and connects masses and radii of the bags with fundamental QCD scales, namely with {lambda}{sub QCD}, , , and quark masses. For high angular momentum states the CSB model well describes hadron Regge trajectories and predicts thin flux tubes with R{sub tube}{approx_equal}0.25 fm close to the small tube radii introduced a posteriori in modern models. For low angular momentum states this model predicts smallmore » radii of the bags R{sub bag}{approx_equal}0.25 fm close to the radii associated with constituent quarks. Masses of the lowest angular momentum bags are obtained close to the data for well known hadron resonances ({pi}(1300), {omega}(1420), N(1440),{delta}(1600), etc.). These resonances are predicted to be almost single bag states. But ground states of SU(3) hadrons (N(940), {pi}(140), etc.) are treated as strongly bounded multi bag states--BagBag-mesons, and BagBagBag-baryons like in the old Fermi, Yang, and Sakata models. As well, this model predicts the low mass excitations of SU(3) hadrons newly observed for nucleons at the following masses 1004, 1044, and 1094 MeV.« less

Zebrafish models of BAG3 myofibrillar myopathy suggest a toxic gain of function leading to BAG3 insufficiency.

PubMed

Ruparelia, Avnika A; Oorschot, Viola; Vaz, Raquel; Ramm, Georg; Bryson-Richardson, Robert J

2014-12-01

Mutations in the co-chaperone Bcl2-associated athanogene 3 (BAG3) can cause myofibrillar myopathy (MFM), a childhood-onset progressive muscle disease, characterized by the formation of protein aggregates and myofibrillar disintegration. In contrast to other MFM-causing proteins, BAG3 has no direct structural role, but regulates autophagy and the degradation of misfolded proteins. To investigate the mechanism of disease in BAG3-related MFM, we expressed wild-type BAG3 or the dominant MFM-causing BAG3 (BAG3(P209L)) in zebrafish. Expression of the mutant protein results in the formation of aggregates that contain wild-type BAG3. Through the stimulation and inhibition of autophagy, we tested the prevailing hypothesis that impaired autophagic function is responsible for the formation of protein aggregates. Contrary to the existing theory, our studies reveal that inhibition of autophagy is not sufficient to induce protein aggregation. Expression of the mutant protein, however, did not induce myofibrillar disintegration and we therefore examined the effect of knocking down Bag3 function. Loss of Bag3 resulted in myofibrillar disintegration, but not in the formation of protein aggregates. Remarkably, BAG3(P209L) is able to rescue the myofibrillar disintegration phenotype, further demonstrating that its function is not impaired. Together, our knockdown and overexpression experiments identify a mechanism whereby BAG3(P209L) aggregates form, gradually reducing the pool of available BAG3, which eventually results in BAG3 insufficiency and myofibrillar disintegration. This mechanism is consistent with the childhood onset and progressive nature of MFM and suggests that reducing aggregation through enhanced degradation or inhibition of nucleation would be an effective therapy for this disease.

Active and passive transport of cargo in a corrugated channel: A lattice model study

NASA Astrophysics Data System (ADS)

Dey, Supravat; Ching, Kevin; Das, Moumita

2018-04-01

Inside cells, cargos such as vesicles and organelles are transported by molecular motors to their correct locations via active motion on cytoskeletal tracks and passive, Brownian diffusion. During the transportation of cargos, motor-cargo complexes (MCCs) navigate the confining and crowded environment of the cytoskeletal network and other macromolecules. Motivated by this, we study a minimal two-state model of motor-driven cargo transport in confinement and predict transport properties that can be tested in experiments. We assume that the motion of the MCC is directly affected by the entropic barrier due to confinement if it is in the passive, unbound state but not in the active, bound state where it moves with a constant bound velocity. We construct a lattice model based on a Fokker Planck description of the two-state system, study it using a kinetic Monte Carlo method and compare our numerical results with analytical expressions for a mean field limit. We find that the effect of confinement strongly depends on the bound velocity and the binding kinetics of the MCC. Confinement effectively reduces the effective diffusivity and average velocity, except when it results in an enhanced average binding rate and thereby leads to a larger average velocity than when unconfined.

Slow positron studies of hydrogen activation/passivation on SiO2/Si(100) interfaces

NASA Astrophysics Data System (ADS)

Lynn, K. G.; Asoka-Kumar, P.

The hydrogen atoms are one of the most common impurity species found in semiconductor systems owing to its large diffusivity, and are easily incorporated either in a controlled process like in ion implantation or in an uncontrolled process like the one at the fabrication stage. Hydrogen can passivate dangling bonds and dislocations in these systems and hence can be used to enhance the electrical properties. In a SiO2/Si system, hydrogen can passivate electronic states at the interface and can alter the fixed or mobile charges in the oxide layer. Since hydrogen is present in almost all of the environments of SiO2/Si wafer fabrication, the activation energy of hydrogen atoms is of paramount importance to a proper understanding of SiO2/Si based devices and has not been measured on the technologically most important Si(100) face. There are no direct, nondestructive methods available to observe hydrogen injection into the oxide layer and subsequent diffusion. The positrons are used as a 'sensitive', nondestructive probe to observe hydrogen interaction in the oxide layer and the interface region. A new way is described of characterizing the changes in the density of the interface states under a low temperature annealing using positrons.

Effects of multilayered bags vs ethylvinyl-acetate bags on oxidation of parenteral nutrition.

PubMed

Balet, Antònia; Cardona, Daniel; Jané, Salvador; Molins-Pujol, Antoni M; Sánchez Quesada, José Luís; Gich, Ignasi; Mangues, Ma Antònia

2004-01-01

We evaluate the effects of multilayered bags vs ethylvinyl-acetate bags on peroxidate formation of various emulsions for all-in-one total parenteral nutrition solutions (TPN) during storage. Twenty-four parenteral nutritions were prepared with 4 commercial i.v. lipid emulsions (Soyacal 20%, Grifols; Intralipid 20%, Fresenius-Kabi; Lipofundina 20%, Braun; and Clinoleic 20%, Clintex) and 2 different bags (multilayered [ML] bag, Miramed; and 1 ethylvinyl-acetate [EVA] bag, Miramed). Each kind of TPN was prepared in triplicate. Samples were taken at 3 different times: immediately after preparation (time 0), after 6 days at 4 degrees C and 48 hours at 37 degrees C (time 1), and finally after a total of 14 days at 37 degrees C (time 2). Oxidation of TPN was evaluated by analysis of hydroperoxides by ferrous oxidation-xylenol orange (FOX) reactive, lipoperoxides by thiobarbituric acid reactive species (TBARS), alpha-tocopherol by high-performance liquid chromatography (HPLC), and ascorbic acid and dehydroascorbic acid by HPLC. TPN admixtures in ML bag showed less oxidation evaluated by peroxide determination using FOX than EVA bag. Lipoperoxides by TBARS did not show significant differences between 2 bags. Ascorbic acid and dehydroascorbic acid disappeared in EVA bags at time 1. No important differences were found in alpha-tocopherol content. Multilayered bags minimize oxidation.

How have changes in air bag designs affected frontal crash mortality?

PubMed

Braver, Elisa R; Shardell, Michelle; Teoh, Eric R

2010-07-01

To determine whether front air bag changes have affected occupant protection, frontal crash mortality rates were compared among front outboard occupants in vehicles having certified-advanced air bags (latest generation of air bags) or sled-certified air bags with and without advanced features. Poisson marginal structural models were used to calculate standardized mortality rate ratios (MRRs) for front occupants per registered vehicle. Vehicle age-corrected mortality rates were lower for drivers of vehicles having sled-certified air bags with advanced features than for drivers having sled-certified air bags without advanced features (MRR = 0.88; 95% confidence interval [CI]: 0.81-0.95), including unbelted men and drivers younger than 60. The mortality rate was higher, though not statistically significant, for drivers having certified-advanced air bags compared with sled-certified air bags with advanced features (vehicle age-corrected MRR = 1.13; 95% CI: 0.97-1.32) and significantly higher for belted drivers (MRR = 1.21; 95% CI: 1.04-1.39). Advanced air bag features appeared protective for some occupants. However, increased mortality rates among belted drivers of vehicles having certified-advanced air bags relative to those having sled-certified air bags with advanced features suggest that further study is needed to identify any potential problems with requirements for certification. 2010 Elsevier Inc. All rights reserved.

Overexpressed BAG3 is a potential therapeutic target in chronic lymphocytic leukemia.

PubMed

Zhu, Huayuan; Wu, Wei; Fu, Yuan; Shen, Wenyi; Miao, Kourong; Hong, Min; Xu, Wei; Young, Ken H; Liu, Peng; Li, Jianyong

2014-03-01

Bcl-2-associated athanogene 3 (BAG3), a member of BAG family, is shown to sustain cell survival and underlie resistance to chemotherapy in human neoplastic cells. We aimed to determine the exact role and underlying mechanisms of BAG3 in human chronic lymphocytic leukemia (CLL). One hundred human CLL samples and 20 normal B-cell samples from healthy controls were collected. We measured the BAG3 expression in these cells and explored its relationship with known prognostic factors for CLL. The roles of BAG3 in cell apoptosis and migration were evaluated by small interfering RNA-mediated knockdown of BAG3 in primary CLL cells. We showed that BAG3 expression level was increased in CLL cells compared with normal B cells. Moreover, BAG3 expression was particularly upregulated in CD38 positive, unmutated immunoglobulin heavy-chain patients and those with lymphadenopathy and/or splenomegaly. Importantly, patients with increased BAG3 expression level have poor overall survival in subgroups with positive ZAP-70 or those without any "p53 abnormality". In addition, knocking down of BAG3 expression resulted in increased apoptotic ratio and decreased migration in primary CLL cells. Our data indicate that BAG3 is a marker of poor prognostic in specific subgroups of CLL patients and may be a potential therapeutic target for this disease.

Impact of storage environment on the efficacy of hermetic storage bags.

PubMed

Lane, Brett; Woloshuk, Charles

2017-05-01

Small hermetic bags (50 and 100 kg capacities) used by smallholder farmers in several African countries have proven to be a low-cost solution for preventing storage losses due to insects. The complexity of postharvest practices and the need for ideal drying conditions, especially in the Sub-Sahara, has led to questions about the efficacy of the hermetic bags for controlling spoilage by fungi and the potential for mycotoxin accumulation. This study compared the effects of environmental temperature and relative humidity at two locations (Indiana and Arkansas) on dry maize (14% moisture content) in woven polypropylene bags and Purdue Improved Crop Storage (PICS) hermetic bags. Temperature and relative humidity data loggers placed in the middle of each bag provided profiles of environmental influences on stored grain at the two locations. The results indicated that the PICS bags prevented moisture penetration over the three-month storage period. In contrast, maize in the woven bags increased in moisture content. For both bag types, no evidence was obtained indicating the spread of Aspergillus flavus from colonized maize to adjacent non-colonized maize. However, other storage fungi did increase during storage. The number of infected kernels did not increase in the PICS bags, but the numbers in the woven bags increased significantly. The warmer environment in Arkansas resulted in significantly higher insect populations in the woven bags than in Indiana. Insects in the PICS bags remained low at both locations. This study demonstrates that the PICS hermetic bags are effective at blocking the effects of external humidity fluctuations as well as the spread of fungi to non-infected kernels.

Performance comparison of plastic shopping bags in modern and traditional retail

NASA Astrophysics Data System (ADS)

Radini, F. A.; Wulandari, R.; Nasiri, S. J. A.; Winarto, D. A.

2017-07-01

Followed by implementation of paid plastic bag policy in Indonesia’s modern and traditional retail, community question related to plastic shopping bag performance arise. But, there is limited information about it. Therefore, the assessment of the performance to compare between plastic shopping bags in modern retail and traditional retail should be interesting. The observation performance of plastic shopping bag were weight holding capacity, tear resistant and elongation. This performance were tested using Universal Testing Machine. Physical and physico-chemical properties also identified to determine factor affecting the performance of plastic shopping bag. The physical properties were analysed using visual and thickness gauge to see the colour and measure the thickness. The analysis of physico-chemical properties were carried out using DSC (Differential Scanning Calorimetry), TGA (Thermal Gravimetry Analysis), Furnace and FTIR (Fourier Transform Infra Red Spectroscopy) to identify the materials, also its melting and decomposition temperature. The result showed that the performance difference between modern retail plastic bag with traditional retail plastic bag appears only in the performance of elongation. The elongation of modern retail plastic bag is 121 - 413%, while traditional has 170 - 609%. According to physico-chemical test result, modern retail and traditional retail plastic bag contain polyethylene as main material and has melting temperature in the range of High Density Polyethylene (HDPE) melting temperature. However, modern retail plastic bag has 18.31 - 33.87% of inorganic filler percentage, whereas the traditional retail plastic bag has 0.35 - 9.85%. This inorganic filler percentage probably a contributing factor in the elongation performance difference between modern retail plastic bag with traditional retail plastic bag.

Bcl2-associated Athanogene 3 Interactome Analysis Reveals a New Role in Modulating Proteasome Activity*

PubMed Central

Chen, Ying; Yang, Li-Na; Cheng, Li; Tu, Shun; Guo, Shu-Juan; Le, Huang-Ying; Xiong, Qian; Mo, Ran; Li, Chong-Yang; Jeong, Jun-Seop; Jiang, Lizhi; Blackshaw, Seth; Bi, Li-Jun; Zhu, Heng; Tao, Sheng-Ce; Ge, Feng

2013-01-01

Bcl2-associated athanogene 3 (BAG3), a member of the BAG family of co-chaperones, plays a critical role in regulating apoptosis, development, cell motility, autophagy, and tumor metastasis and in mediating cell adaptive responses to stressful stimuli. BAG3 carries a BAG domain, a WW domain, and a proline-rich repeat (PXXP), all of which mediate binding to different partners. To elucidate BAG3's interaction network at the molecular level, we employed quantitative immunoprecipitation combined with knockdown and human proteome microarrays to comprehensively profile the BAG3 interactome in humans. We identified a total of 382 BAG3-interacting proteins with diverse functions, including transferase activity, nucleic acid binding, transcription factors, proteases, and chaperones, suggesting that BAG3 is a critical regulator of diverse cellular functions. In addition, we characterized interactions between BAG3 and some of its newly identified partners in greater detail. In particular, bioinformatic analysis revealed that the BAG3 interactome is strongly enriched in proteins functioning within the proteasome-ubiquitination process and that compose the proteasome complex itself, suggesting that a critical biological function of BAG3 is associated with the proteasome. Functional studies demonstrated that BAG3 indeed interacts with the proteasome and modulates its activity, sustaining cell survival and underlying resistance to therapy through the down-modulation of apoptosis. Taken as a whole, this study expands our knowledge of the BAG3 interactome, provides a valuable resource for understanding how BAG3 affects different cellular functions, and demonstrates that biologically relevant data can be harvested using this kind of integrated approach. PMID:23824909

An investigation of red blood cell concentrate quality during storage in paediatric-sized polyvinylchloride bags plasticized with alternatives to di-2-ethylhexyl phthalate (DEHP).

PubMed

Serrano, K; Levin, E; Chen, D; Hansen, A; Turner, T R; Kurach, J; Reidel, A; Boecker, W F; Acker, J P; Devine, D V

2016-04-01

Di-2-ethylhexyl phthalate (DEHP) is a blood bag plasticizer. It is also a toxin, raising concerns for vulnerable populations, for example, neonates and infants. Here, the in vitro quality of red cell concentrates (RCC) stored in paediatric bags formulated with alternative plasticizers to DEHP was compared. RCC were pooled and split into polyvinylchloride (PVC)/DEHP, PVC/1,2-cyclohexanedicarboxylic acid diisononyl ester (DINCH) or PVC/butyryl trihexyl citrate (BTHC) bags. Quality was assessed on storage days 5, 21, 35 and 43. Metabolism differed among the bags: pCO2 levels were lowest and pO2 were highest in BTHC bags. Glucose consumption and lactate production suggested higher metabolic rates in BTHC bags. ATP levels were best maintained in DINCH bags (day 43 mean level: 2·86 ± 0·29 μmol/g Hb). RCC in BTHC bags had the greatest potassium release (54·6 ± 3·0 mm on day 43). From day 21, haemolysis was higher in BTHC bags (P < 0·01) and by day 43 had exceeded 0·8% (0·85 ± 0·10%). RCC in BTHC bags showed more microparticle formation than RCC in DEHP or DINCH bags. The results suggest that the BTHC formulation used was detrimental to RBC quality. DINCH bags could be a viable alternative to DEHP: they outperformed DEHP bags energetically, with better maintenance of ATP levels. © 2015 International Society of Blood Transfusion.

CVD-Based Valence-Mending Passivation for Crystalline-Si Solar Cells

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

Tao, Meng

2015-03-01

The objective of this project is to investigate a new surface passivation technique, valence-mending passivation, for its applications in crystalline-Si solar cells to achieve significant efficiency improvement and cost reduction. As the enabling technique, the project includes the development of chemical vapor deposition recipes to passivate textured Si(100) and multicrystalline-Si surfaces by sulfur and the characterization of the passivated Si surfaces, including thermal stability, Schottky barrier height, contact resistance and surface recombination. One important application is to replace the Ag finger electrode in Si cells with Al to reduce cost, by ~$0.1/Wp, and allow terawatt-scale deployment of crystalline-Si solar cells.more » These all-Al Si cells require a low-temperature metallization process for the Al electrode, to be compatible with valence-mending passivation and to prevent Al diffusion into n-type Si. Another application is to explore valence-mending passivation of grain boundaries in multicrystalline Si by diffusing sulfur into grain boundaries, to reduce the efficiency gas between monocrystalline-Si solar cells and multicrystalline-Si cells. The major accomplishments of this project include: 1) Demonstration of chemical vapor deposition processes for valence-mending passivation of both monocrystalline Si(100) and multicrystalline Si surfaces. Record Schottky barriers have been demonstrated, with the new record-low barrier of less than 0.08 eV between Al and sulfur-passivated n-type Si(100) and the new record-high barrier of 1.14 eV between Al and sulfur-passivated p-type Si(100). On the textured p-type monocrystalline Si(100) surface, the highest barrier with Al is 0.85 eV by valence-mending passivation. 2) Demonstration of a low-temperature metallization process for Al in crystalline-Si solar cells. The new metallization process is based on electroplating of Al in a room-temperature ionic liquid. The resistivity of the electroplated Al is ~7×10–6 ohm-cm, similar to that of screen-printed Ag. 3) Demonstration of two all-Al, Ag-free Si solar cells, with an electroplated Al front electrode and a screen-printed Al back electrode. One cell is an industrial p-type front-emitter cell, and the other is an n-type back-emitter cell. The efficiency of the p-type cell is close to 15%. This is an industrial cell and its efficiency is capped at ~18%. 4) Demonstration of grain boundary passivation by both hydrogen and sulfur using hydrogen sulfide (H2S). When the new grain boundary passivation is combined with Al2O3 surface passivation and post-annealing, the minority carrier lifetime in the p-type multicrystalline Si samples shows a significant improvement up to 68 fold. 5) In a side project, a simple green process is developed which is capable of recycling over 90% of the Si material in end-of-life crystalline-Si solar cells. The recycled Si meets the specifications for solar-grade Si and can be used as a new poly-Si feedstock for ingot growth.« less

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

Liu, Zhixiao; Mukherjee, Partha P.

We report the cathode surface passivation caused by Li 2S precipitation adversely affects the performance of lithium-sulfur (Li-S) batteries. Li 2S precipitation is a complicated mesoscale process involving adsorption, desorption and diffusion kinetics, which are affected profoundly by the reactant concentration and operating temperature. In this work, a mesoscale interfacial model is presented to study the growth of Li 2S film on carbon cathode surface. Li 2S film growth experiences nucleation, isolated Li 2S island growth and island coalescence. The slow adsorption rate at small S 2- concentration inhibits the formation of nucleation seeds and the lateral growth of Limore » 2S islands, which deters surface passivation. An appropriate operating temperature, especially in the medium-to-high temperature range, can also defer surface passivation. Fewer Li 2S nucleation seeds form in such an operating temperature range, which facilitates heterogeneous growth and thereby inhibits the lateral growth of the Li 2S film, which may also result in reduced surface passivation. Finally, the high specific surface area of the cathode microstructure is expected to mitigate the surface passivation.« less

Optimized ultra-thin manganin alloy passivated fine-pitch damascene compatible bump-less Cu-Cu bonding at sub 200 °C for three-dimensional Integration applications

NASA Astrophysics Data System (ADS)

Panigrahi, Asisa Kumar; Hemanth Kumar, C.; Bonam, Satish; Ghosh, Tamal; Rama Krishna Vanjari, Siva; Govind Singh, Shiv

2018-02-01

Enhanced Cu diffusion, Cu surface passivation, and smooth surface at the bonding interface are the key essentials for high quality Cu-Cu bonding. Previously, we have demonstrated optimized 3 nm thin Manganin metal-alloy passivation from oxidation and also helps to reduce the surface roughness to about 0.8 nm which substantially led to high quality Cu-Cu bonding. In this paper, we demonstrated an ultra fine-pitch (<25 µm) Cu-Cu bonding using an optimized Manganin metal-alloy passivation. This engineered surface passivation approach led to high quality bonding at sub 200 °C temperature and 0.4 MPa. Very low specific contact resistance of 1.4 × 10-7 Ω cm2 and the defect free bonded interface is clear indication of high quality bonding for future multilayer integrations. Furthermore, electrical characterization of the bonded structure was performed under various robust conditions as per International Technology Roadmap for Semiconductors (ITRS Roadmap) in order to satisfy the stability of the bonded structure.

Reduction of plastic carrier bag use: An analysis of alternatives in Israel.

PubMed

Ayalon, Ofira; Goldrath, Tal; Rosenthal, Gad; Grossman, Michal

2009-07-01

Plastic carrier bags have been drawing the attention of the public and politicians. Different policy measures to reduce the environmental burden of these bags have been implemented and more are planned. The research analyzed the actual environmental aspects of consumption and use of plastic carrier bags and assessed the effectiveness of the proposed regulation in Israel. Since plastic bags are provided free of charge, people have a tendency to use these bags excessively, therefore a rigorous educational program should address this trend. However, the environmental load imposed by the bags is more a politically correct issue than an actual environmental hazard, and therefore the means for reducing their use should not include a high levy or total elimination of these bags.

Comparison of cryopreservation bags for hematopoietic progenitor cells using a WBC-enriched product.

PubMed

Dijkstra-Tiekstra, Margriet J; Hazelaar, Sandra; Gkoumassi, Effimia; Weggemans, Margienus; de Wildt-Eggen, Janny

2015-04-01

Hematopoietic progenitor cells (HPC) are stored in cryopreservation bags that are resistant to liquid nitrogen. Since Cryocyte bags of Baxter (B-bags) are no longer available, an alternative bag was sought. Also, the influence of freezing volume was studied. Miltenyi Biotec (MB)- and MacoPharma (MP)-bags passed the integrity tests without failure. Comparing MB- and MP-bags with B-bags, no difference in WBC recovery or viability was found when using a WBC-enriched product as a "dummy" HPC product. Further, a freezing volume of 30 mL resulted in better WBC recovery and viability than 60 mL. Additonal studies using real HPC might be necessary. Copyright © 2014 Elsevier Ltd. All rights reserved.

Some Insights into Analytical Bias Involved in the Application of Grab Sampling for Volatile Organic Compounds: A Case Study against Used Tedlar Bags

PubMed Central

Ghosh, Samik; Kim, Ki-Hyun; Sohn, Jong Ryeul

2011-01-01

In this study, we have examined the patterns of VOCs released from used Tedlar bags that were once used for the collection under strong source activities. In this way, we attempted to account for the possible bias associated with the repetitive use of Tedlar bags. To this end, we selected the bags that were never heated. All of these target bags were used in ambient temperature (typically at or below 30°C). These bags were also dealt carefully to avoid any mechanical abrasion. This study will provide the essential information regarding the interaction between VOCs and Tedlar bag materials as a potential source of bias in bag sampling approaches. PMID:22235175

Some insights into analytical bias involved in the application of grab sampling for volatile organic compounds: a case study against used Tedlar bags.

PubMed

Ghosh, Samik; Kim, Ki-Hyun; Sohn, Jong Ryeul

2011-01-01

In this study, we have examined the patterns of VOCs released from used Tedlar bags that were once used for the collection under strong source activities. In this way, we attempted to account for the possible bias associated with the repetitive use of Tedlar bags. To this end, we selected the bags that were never heated. All of these target bags were used in ambient temperature (typically at or below 30°C). These bags were also dealt carefully to avoid any mechanical abrasion. This study will provide the essential information regarding the interaction between VOCs and Tedlar bag materials as a potential source of bias in bag sampling approaches.

Legitimization of regulatory norms: Waterfowl hunter acceptance of changing duck bag limits

USGS Publications Warehouse

Schroeder, Susan A.; Fulton, David C.; Lawrence, Jeffrey S.; Cordts, Steven D.

2014-01-01

Few studies have examined response to regulatory change over time, or addressed hunter attitudes about changes in hunting bag limits. This article explores Minnesota waterfowl hunters’ attitudes about duck bag limits, examining attitudes about two state duck bag limits that were initially more restrictive than the maximum set by the U.S. Fish and Wildlife Service (USFWS), but then increased to match federal limits. Results are from four mail surveys that examined attitudes about bag limits over time. Following two bag limit increases, a greater proportion of hunters rated the new bag limit “too high” and a smaller proportion rated it “too low.” Several years following the first bag limit increase, the proportion of hunters who indicated that the limit was “too high” had declined, suggesting hunter acceptance of the new regulation. Results suggest that waterfowl bag limits may represent legal norms that influence hunter attitudes and gain legitimacy over time.

Silencing of BAG3 inhibits the epithelial-mesenchymal transition in human cervical cancer.

PubMed

Song, Fei; Wang, Geng; Ma, Zhifang; Ma, Yuebing; Wang, Yingying

2017-11-10

Bcl2-associated athanogene 3 (BAG3) has been reported to be involved in aggressive progression of many tumors. In the present study, we examined the expression of BAG3 in human cervical cancer (CC) tissues and investigated the role of BAG3 in SiHa and HeLa cell growth, migration, and invasion. Here, we found that most of CC tissues highly expressed the protein and mRNA of BAG3, while their expression was obviously lower in paired normal tissues (all p<0.001). BAG3 expression was associated with FIGO stage and metastasis (all p<0.05). In-vitro analysis demonstrated that BAG3 siRNAs inhibited SiHa and HeLa cell growth, invasion and migration. Mechanically, BAG3 siRNAs inhibited the expression of EMT-regulating markers, involving MMP2, Slug and N-cadherin, and increased the expression of E-cadherin. In a xenograft nude model, BAG3 siRNAs inhibited tumor growth and the expression of EMT biomarkers. In conclusion, BAG3 is involved in the EMT process, including cell growth, invasion and migration in the development of CC. Thus, BAG3 target might be recommended as a novel therapeutic approach.

Silencing of BAG3 inhibits the epithelial-mesenchymal transition in human cervical cancer

PubMed Central

Song, Fei; Wang, Geng; Ma, Zhifang; Ma, Yuebing; Wang, Yingying

2017-01-01

Bcl2-associated athanogene 3 (BAG3) has been reported to be involved in aggressive progression of many tumors. In the present study, we examined the expression of BAG3 in human cervical cancer (CC) tissues and investigated the role of BAG3 in SiHa and HeLa cell growth, migration, and invasion. Here, we found that most of CC tissues highly expressed the protein and mRNA of BAG3, while their expression was obviously lower in paired normal tissues (all p<0.001). BAG3 expression was associated with FIGO stage and metastasis (all p<0.05). In-vitro analysis demonstrated that BAG3 siRNAs inhibited SiHa and HeLa cell growth, invasion and migration. Mechanically, BAG3 siRNAs inhibited the expression of EMT-regulating markers, involving MMP2, Slug and N-cadherin, and increased the expression of E-cadherin. In a xenograft nude model, BAG3 siRNAs inhibited tumor growth and the expression of EMT biomarkers. In conclusion, BAG3 is involved in the EMT process, including cell growth, invasion and migration in the development of CC. Thus, BAG3 target might be recommended as a novel therapeutic approach. PMID:29221135

Bagworm bags as portable armour against invertebrate predators

PubMed Central

2016-01-01

Some animals have evolved the use of environmental materials as “portable armour” against natural enemies. Portable bags that bagworm larvae (Lepidoptera: Psychidae) construct using their own silk and plant parts are generally believed to play an important role as a physical barrier against natural enemies. However, no experimental studies have tested the importance of bags as portable armour against predators. To clarify the defensive function, I studied the bagworm Eumeta minuscula and a potential predator Calosoma maximoviczi (Coleoptera: Carabidae). Under laboratory conditions, all bagworm larvae were attacked by carabid adults, but successfully defended themselves against the predators’ mandibles using their own bags. The portable bags, which are composed mainly of host plant twigs, may function as a physical barrier against predator mandibles. To test this hypothesis, I removed the twig bags and replaced some with herb leaf bags; all bag-removed larvae were easily caught and predated by carabids, while all bag-replaced larvae could successfully defend themselves against carabid attacks. Therefore, various types of portable bags can protect bagworm larvae from carabid attacks. This is the first study to test the defensive function of bagworm portable bags against invertebrate predators. PMID:26893969

Warming preterm infants in the delivery room: polyethylene bags, exothermic mattresses or both?

PubMed

McCarthy, Lisa K; O'Donnell, Colm P F

2011-12-01

To compare the admission temperature of infants treated with polyethylene bags alone to infants treated with exothermic mattresses in addition to bags in the delivery room. We prospectively studied infants born at <31 weeks' gestation who were placed in bags at birth. Some infants were also placed on mattresses. Admission axillary temperatures were measured in all infants on admission to the neonatal intensive care. We compared the temperatures of infants treated with bags alone to those treated with mattresses and bags. We studied 43 infants: 15 were treated with bags while 28 were treated with a bag and mattress. Mean admission temperature was similar between the groups. Hypothermia and hyperthermia occurred more frequently in infants treated with a bag and mattress, and more infants treated with a bag had admission temperatures 36.5-37.5°C. The use of exothermic mattresses in addition to polyethylene bags, particularly in younger, smaller newborns, may result in more hypothermia and hyperthermia on admission. A randomised controlled trial is necessary to determine which strategy results in more infants having admission temperatures in the normal range. © 2011 The Author(s)/Acta Paediatrica © 2011 Foundation Acta Paediatrica.

High expression of BAG3 predicts a poor prognosis in human medulloblastoma.

PubMed

Yang, Dong; Zhou, Ji; Wang, Hao; Wang, Yutao; Yang, Ge; Zhang, Yundong

2016-10-01

Bcl2-associated athanogene 3 (BAG3), a co-chaperone of the heat shock protein (Hsp) 70, regulates various physiological and pathological processes. However, its role in human medulloblastoma has not been clarified. First of all, the expression of BAG3 was examined in formalin-fixed, paraffin-embedded specimens by immunohistochemical staining. And then, the prognostic role of BAG3 was analyzed in 51 medulloblastoma samples. Finally, the roles of BAG3 in the proliferation, migration, and invasion of Daoy medulloblastoma cell were investigated using a specific short hairpin RNA (shRNA). The expression of BAG3 in medulloblastoma tissues was higher than nontumorous samples. Furthermore, BAG3 overexpression significantly correlated with poor prognosis of patients with medulloblastoma. The overall survival and tumor-free survival in patients with BAG3 low expression were higher than high expression. Univariate and multivariate analysis showed that BAG3 overexpression was an independent prognostic marker for medulloblastoma. After the BAG3 knockdown, the Daoy cells exhibited decreased the ability to proliferate and form neurosphere. The preliminary mechanism study showed that overexpression of BAG3 might facilitate the cell cycle transition from G1 to S phase by modulating the cyclin-dependent kinase 2 (CDK2) and cyclin E expression. Additionally, we found that BAG3 might enhance the medulloblastoma cell migratory and invasive ability. In summary, BAG3 overexpression may regulate the survival and invasive properties of medulloblastoma and may serve as a potential therapy target for medulloblastoma.

BAG3: a multifaceted protein that regulates major cell pathways

PubMed Central

Rosati, A; Graziano, V; De Laurenzi, V; Pascale, M; Turco, M C

2011-01-01

Bcl2-associated athanogene 3 (BAG3) protein is a member of BAG family of co-chaperones that interacts with the ATPase domain of the heat shock protein (Hsp) 70 through BAG domain (110–124 amino acids). BAG3 is the only member of the family to be induced by stressful stimuli, mainly through the activity of heat shock factor 1 on bag3 gene promoter. In addition to the BAG domain, BAG3 contains also a WW domain and a proline-rich (PXXP) repeat, that mediate binding to partners different from Hsp70. These multifaceted interactions underlie BAG3 ability to modulate major biological processes, that is, apoptosis, development, cytoskeleton organization and autophagy, thereby mediating cell adaptive responses to stressful stimuli. In normal cells, BAG3 is constitutively present in a very few cell types, including cardiomyocytes and skeletal muscle cells, in which the protein appears to contribute to cell resistance to mechanical stress. A growing body of evidence indicate that BAG3 is instead expressed in several tumor types. In different tumor contexts, BAG3 protein was reported to sustain cell survival, resistance to therapy, and/or motility and metastatization. In some tumor types, down-modulation of BAG3 levels was shown, as a proof-of-principle, to inhibit neoplastic cell growth in animal models. This review attempts to outline the emerging mechanisms that can underlie some of the biological activities of the protein, focusing on implications in tumor progression. PMID:21472004

[Expression of BAG3 Gene in Acute Myeloid Leukemia and Its Prognostic Value].

PubMed

Zhu, Hua-Yuan; Fu, Yuan; Wu, Wei; Xu, Jia-Dai; Chen, Ting-Mei; Qiao, Chun; Li, Jian-Yong; Liu, Peng

2015-08-01

To investigate the expression of BAG3 gene in acue myeloid leukemia (AML) and its prognostic value. Real-time quantitative RT-PCR was used to detect the expression of BAG3 mRNA in 88 previously untreated AML patients. The corelation of BAG3 expression level with clinical characteristics and known prognostic markers of AML was analyzed. In 88 patients with AML, the expression of BAG3 mRNA in NPMI mutated AML patients was obviously lower than that in NPMI unmutated patients (P = 0.018). The expression level of BAG3 mRNA did not related to clinical parameters, such as age, sex, FAB subtype, WBC count, extra-modullary presentation, and to prognostic factors including cytogenetics, FLT3-ITD, c-kit and CEBPα mutation status (P > 0.05). The expression level of BAG3 had no obvious effect on complete remission (CR) of patients in first treatment. The expression level of BAG3 in non-M3 patients was higher than that in relapsed patients (P = 0.036). The expression level of BAG3 had no effect on overall survival (OS) of patients. The expression level of BAG3 does not correlated with known-prognostic markers of AML, only the expression level of BAG3 in NPM1 mutated patients is lower than that in NPM1 unmutated patients. The expression level of BAG3 has no effect on OS of AML patients, the BAG3 can not be difined as a prognostic marker in AML.

Mixing of two solutions combined by gravity drainage.

PubMed

Leuptow, R M; Smith, K; Mockros, L F

1995-01-01

A variety of medical therapies require the mixing of solutions from two separate bags before use. One scenario for the mixing is to drain the solution from one bag into the other by gravity through a short connecting tube. The degree of mixing in the lower bag depends on the relative densities of the two solutions, the geometry of the two bags and the connecting tube, and the placement of the connecting tube. Solutions with densities differing by as much as 12% were mixed by draining the solution from an upper bag into a lower bag for a particular geometric configuration. The two solutions had different electrical conductivities, and the conductivity of the combined solution as it exited from the lower bag was used as a measure of the effectiveness of mixing. When the more dense solution was drained from the upper bag into the less dense solution in a lower bag, mixing was very effective. The incoming jet of high density solution entrained the low density solution. Flow visualization indicated that the incoming jet penetrated to the bottom of the lower bag, and resulting large vortical structures enhanced mixing. When the less dense solution was drained from the upper bag into the more dense solution in the lower bag mixing was less effective. The buoyancy force reduced the momentum of the incoming jet such that it did not penetrate to the bottom of the lower bag, resulting in stratification of the solutions.

Prospecting for zones of contaminated ground-water discharge to streams using bottom-sediment gas bubbles

USGS Publications Warehouse

Vroblesky, Don A.; Lorah, Michelle M.

1991-01-01

Decomposition of organic-rich bottom sediment in a tidal creek in Maryland results in production of gas bubbles in the bottom sediment during summer and fall. In areas where volatile organic contaminants discharge from ground water, through the bottom sediment, and into the creek, part of the volatile contamination diffuses into the gas bubbles and is released to the atmosphere by ebullition. Collection and analysis of gas bubbles for their volatile organic contaminant content indicate that relative concentrations of the volatile organic contaminants in the gas bubbles are substantially higher in areas where the same contaminants occur in the ground water that discharges to the streams. Analyses of the bubbles located an area of previously unknown ground-water contamination. The method developed for this study consisted of disturbing the bottom sediment to release gas bubbles, and then capturing the bubbles in a polyethylene bag at the water-column surface. The captured gas was transferred either into sealable polyethylene bags for immediate analysis with a photoionization detector or by syringe to glass tubes containing wires coated with an activated-carbon adsorbent. Relative concentrations were determined by mass spectral analysis for chloroform and trichloroethylene.

Population pharmacokinetic modelling of non-linear brain distribution of morphine: influence of active saturable influx and P-glycoprotein mediated efflux

PubMed Central

Groenendaal, D; Freijer, J; de Mik, D; Bouw, M R; Danhof, M; de Lange, E C M

2007-01-01

Background and purpose: Biophase equilibration must be considered to gain insight into the mechanisms underlying the pharmacokinetic-pharmacodynamic (PK-PD) correlations of opioids. The objective was to characterise in a quantitative manner the non-linear distribution kinetics of morphine in brain. Experimental approach: Male rats received a 10-min infusion of 4 mg kg−1 of morphine, combined with a continuous infusion of the P-glycoprotein (Pgp) inhibitor GF120918 or vehicle, or 40 mg kg−1 morphine alone. Unbound extracellular fluid (ECF) concentrations obtained by intracerebral microdialysis and total blood concentrations were analysed using a population modelling approach. Key results: Blood pharmacokinetics of morphine was best described with a three-compartment model and was not influenced by GF120918. Non-linear distribution kinetics in brain ECF was observed with increasing dose. A one compartment distribution model was developed, with separate expressions for passive diffusion, active saturable influx and active efflux by Pgp. The passive diffusion rate constant was 0.0014 min−1. The active efflux rate constant decreased from 0.0195 min−1 to 0.0113 min−1 in the presence of GF120918. The active influx was insensitive to GF120918 and had a maximum transport (Nmax/Vecf) of 0.66 ng min−1 ml−1 and was saturated at low concentrations of morphine (C50=9.9 ng ml−1). Conclusions and implications: Brain distribution of morphine is determined by three factors: limited passive diffusion; active efflux, reduced by 42% by Pgp inhibition; low capacity active uptake. This implies blood concentration-dependency and sensitivity to drug-drug interactions. These factors should be taken into account in further investigations on PK-PD correlations of morphine. PMID:17471182

Controlled release of optimized electroporation enhances the transdermal efficiency of sinomenine hydrochloride for treating arthritis in vitro and in clinic

PubMed Central

Feng, Shun; Zhu, Lijun; Huang, Zhisheng; Wang, Haojia; Li, Hong; Zhou, Hua; Lu, Linlin; Wang, Ying; Liu, Zhongqiu; Liu, Liang

2017-01-01

Sinomenine hydrochloride (SH) is an ideal drug for the treatment of rheumatoid arthritis and osteoarthritis. However, high plasma concentration of systemically administered SH can release histamine, which can cause rash and gastrointestinal side effects. Topical delivery can increase SH concentration in the synovial fluid without high plasma level, thus minimizing systemic side effects. However, passive diffusion of SH was found to be inefficient because of the presence of the stratum corneum layer. Therefore, an effective method is required to compensate for the low efficiency of SH passive diffusion. In this study, transdermal experiments in vitro and clinical tests were utilized to explore the optimized parameters for electroporation of topical delivery for SH. Fluorescence experiment and hematoxylin and eosin staining analysis were performed to reveal the mechanism by which electroporation promoted permeation. In vitro, optimized electroporation parameters were 3 KHz, exponential waveform, and intensity 10. Using these parameters, transdermal permeation of SH was increased by 1.9–10.1 fold in mice skin and by 1.6–47.1 fold in miniature pig skin compared with passive diffusion. After the electroporation stimulation, the intercellular intervals and epidermal cracks in the skin increased. In clinical tests, SH concentration in synovial fluid was 20.84 ng/mL after treatment with electroporation. Therefore, electroporation with optimized parameters could significantly enhance transdermal permeation of SH. The mechanism by which electroporation promoted permeation was that the electronic pulses made the skin structure looser. To summarize, electroporation may be an effective complementary method for transdermal permeation of SH. The controlled release of electroporation may be a promising clinical method for transdermal drug administration. PMID:28670109

Evolution of Antibody-Drug Conjugate Tumor Disposition Model to Predict Preclinical Tumor Pharmacokinetics of Trastuzumab-Emtansine (T-DM1).

PubMed

Singh, Aman P; Maass, Katie F; Betts, Alison M; Wittrup, K Dane; Kulkarni, Chethana; King, Lindsay E; Khot, Antari; Shah, Dhaval K

2016-07-01

A mathematical model capable of accurately characterizing intracellular disposition of ADCs is essential for a priori predicting unconjugated drug concentrations inside the tumor. Towards this goal, the objectives of this manuscript were to: (1) evolve previously published cellular disposition model of ADC with more intracellular details to characterize the disposition of T-DM1 in different HER2 expressing cell lines, (2) integrate the improved cellular model with the ADC tumor disposition model to a priori predict DM1 concentrations in a preclinical tumor model, and (3) identify prominent pathways and sensitive parameters associated with intracellular activation of ADCs. The cellular disposition model was augmented by incorporating intracellular ADC degradation and passive diffusion of unconjugated drug across tumor cells. Different biomeasures and chemomeasures for T-DM1, quantified in the companion manuscript, were incorporated into the modified model of ADC to characterize in vitro pharmacokinetics of T-DM1 in three HER2+ cell lines. When the cellular model was integrated with the tumor disposition model, the model was able to a priori predict tumor DM1 concentrations in xenograft mice. Pathway analysis suggested different contribution of antigen-mediated and passive diffusion pathways for intracellular unconjugated drug exposure between in vitro and in vivo systems. Global and local sensitivity analyses revealed that non-specific deconjugation and passive diffusion of the drug across tumor cell membrane are key parameters for drug exposure inside a cell. Finally, a systems pharmacokinetic model for intracellular processing of ADCs has been proposed to highlight our current understanding about the determinants of ADC activation inside a cell.

Towards Stable Lithium-Sulfur Batteries with a Low Self-Discharge Rate: Ion Diffusion Modulation and Anode Protection.

PubMed

Xu, Wen-Tao; Peng, Hong-Jie; Huang, Jia-Qi; Zhao, Chen-Zi; Cheng, Xin-Bing; Zhang, Qiang

2015-09-07

The self-discharge of a lithium-sulfur cell decreases the shelf-life of the battery and is one of the bottlenecks that hinders its practical applications. New insights into both the internal chemical reactions in a lithium-sulfur system and effective routes to retard self-discharge for highly stable batteries are crucial for the design of lithium-sulfur cells. Herein, a lithium-sulfur cell with a carbon nanotube/sulfur cathode and lithium-metal anode in lithium bis(trifluoromethanesulfonyl)imide/1,3-dioxolane/dimethyl ether electrolyte was selected as the model system to investigate the self-discharge behavior. Both lithium anode passivation and polysulfide anion diffusion suppression strategies are applied to reduce self-discharge of the lithium-sulfur cell. When the lithium-metal anode is protected by a high density passivation layer induced by LiNO3 , a very low shuttle constant of 0.017 h(-1) is achieved. The diffusion of the polysulfides is retarded by an ion-selective separator, and the shuttle constants decreased. The cell with LiNO3 additive maintained a discharge capacity of 97 % (961 mAh g(-1) ) of the initial capacity after 120 days at open circuit, which was around three times higher than the routine cell (32 % of initial capacity, corresponding to 320 mAh g(-1) ). It is expected that lithium-sulfur batteries with ultralow self-discharge rates may be fabricated through a combination of anode passivation and polysulfide shuttle control, as well as optimization of the lithium-sulfur cell configuration. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diffusive gradients in thin-films (DGT) for in situ sampling of selected endocrine disrupting chemicals (EDCs) in waters.

PubMed

Chen, Wei; Pan, Suhong; Cheng, Hao; Sweetman, Andrew J; Zhang, Hao; Jones, Kevin C

2018-06-15

A passive water sampler based on the diffusive gradients in thin-films (DGT) technique was developed and tested for 3 groups of endocrine disrupting chemicals (EDCs, including oestrogens, alkyl-phenols and bisphenols). Three different resins (hydrophilic-lipophilic-balanced (HLB), XAD18 and Strata-XL-A (SXLA)) were investigated for their suitability as the binding phase for DGT devices. Laboratory tests across a range of pH (3.5-9.5), ionic strength (0.001-0.5 M) and dissolved organic matter concentration (0-20 mg L -1 ) showed HLB and XAD18-DGT devices were more stable compared to SXLA-DGT. HLB-DGT and XAD18-DGT accumulated test chemicals with time consistent with theoretical predictions, while SXLA-DGT accumulated reduced amounts of chemical. DGT performance was also compared in field deployments up to 28 days, alongside conventional active sampling at a wastewater treatment plant. Uptake was linear to the samplers over 18 days, and then began to plateau/decline, indicating the maximum deployment time in those conditions. Concentrations provided by the DGT samplers compared well with those provided by auto-samplers. DGT integrated concentrations over the deployment period in a way that grab-sampling cannot. The advantages of the DGT sampler over active sampling include: low cost, ease of simultaneous multi-site deployment, in situ analyte pre-concentration and reduction of matrix interferences compared with conventional methods. Compared to other passive sampler designs, DGT uptake is independent of flow rate and therefore allows direct derivation of field concentrations from measured compound diffusion coefficients. This passive DGT sampler therefore constitutes a viable and attractive alternative to conventional grab and active water sampling for routine monitoring of selected EDCs. Copyright © 2018 Elsevier Ltd. All rights reserved.

BAG3 promotes chondrosarcoma progression by upregulating the expression of β-catenin

PubMed Central

Shi, Huijuan; Chen, Wenfang; Dong, Yu; Lu, Xiaofang; Zhang, Wenhui; Wang, Liantang

2018-01-01

To investigate the roles of B-cell lymphoma-2 associated athanogene 3 (BAG3) in human chondrosarcoma and the potential mechanisms, the expression levels of BAG3 were detected in the present study, and the associations between BAG3 and clinical pathological parameters, clinical stage as well as the survival of patients were analyzed. The present study detected BAG3 mRNA and protein expression in the normal cartilage cell line HC-a and in SW1353 chondrosarcoma cells by reverse transcription-quantitative polymerase chain reaction and western blot analysis. The BAG3 protein expression in 59 cases of chondrosarcoma, 30 patients with endogenous chondroma and 8 cases of normal cartilage was semi-quantitatively analyzed using the immunohistochemical method. In addition, the BAG3 protein expression level, the clinical pathological parameters, clinical stage and the survival time of patients with chondrosarcoma were analyzed. The plasmid transfection method was employed to upregulate the expression BAG3 and small RNA interference to downregulate the expression of BAG3 in SW1353 cells. The expression levels of BAG3 protein and mRNA were significantly increased in the chondrosarcoma cell line when compared with the normal cartilage cell line. The immunohistochemistry results indicated that BAG3 protein was overexpressed in the tissue of human chondrosarcoma. Statistical analysis showed that the expression level of BAG3 was significantly increased in the different Enneking staging of patients with chondrosarcoma and Tumor staging, and there were no statistical differences in age, gender, histological classification and tumor size. In the in vitro experiments, the data revealed that BAG3 significantly promoted chondrosarcoma cell proliferation, colony-formation, migration and invasion; however, it inhibited chondrosarcoma cell apoptosis. It was observed that BAG3 upregulated β-catenin expression at the mRNA and protein levels. In addition, BAG3 induced the expression of runt-related transcription factor 2 (RUNX2) in chondrosarcoma cells by upregulating β-catenin. These clinical analyses revealed a positive association between β-catenin and BAG3 in chondrosarcoma tumors. BAG3 was significantly increased in chondrosarcoma cells and tissues compared with the normal cartilage cells, tissue and cartilage benign tumors. Thus, BAG3 may serve as an oncogene in the development of chondrosarcoma via the induction of RUNX2 expression. The results of the present study contribute to further research on the biological development of chondrosarcoma. PMID:29484408

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

Young, David L.; Lee, Benjamin G.; Fogel, Derek

Here, we form gallium-doped poly-Si:Ga/SiO 2 passivated contacts on n-type Czochralski (n-Cz) wafers using ion implantation of Ga and Ga-containing spin-on dopants. After annealing and passivation with Al 2O 3, the contacts exhibit i Voc values of >730 mV with corresponding Joe values of <5 fA/cm 2. These are among the best-reported values for p-type poly-Si/SiO 2 contacts. Secondary ion mass spectroscopic depth profile data show that, in contrast to B, Ga does not pileup at the SiO 2 interface in agreement with its known high diffusivity in SiO 2. This lack of Ga pileup may imply fewer dopant-related defectsmore » in the SiO 2, compared with B dopants, and account for the excellent passivation.« less

Investigating reduced bag weight as an effective risk mediator for mason tenders.

PubMed

Davis, Kermit G; Kotowski, Susan E; Albers, James; Marras, William S

2010-10-01

Masonry workers face some of the highest physical demands in the construction industry where large bags of masonry material weighing 42.7 kg are commonly handled by mason tenders who mix the mortar, distribute mortar and bricks/blocks, and erect/dismantle scaffolding throughout the day. The objective of this study was to determine the effectiveness of using half-weight bags (21.4 kg) on reducing the biomechanical loading, physiological response, and perceived exertions. Ten male subjects performed asymmetric lifting tasks simulating unloading bags from a pallet. Muscle activity, trunk kinematics, heart rate, blood pressure and subjective rating data were collected. Spine loads were predicted from a well-validated EMG-assisted model. Bag weight, lift type, bag height at origin, and asymmetry at destination significantly impacted the spine loads. While there was a 50% reduction in bag weight, the peak loads for the half-weight bags were only 25% less than the more available full-weight bags (a reduction of about 320 N of shear and 1000 N of compression). Lifts allowing movement of the feet reduced the loads by about 22% in shear and 27% in compression compared to constrained postures. Interestingly, cumulative spine loads were greater for the lighter bags than the heavy bags ( approximately 40%). The subjective ratings of exertion and risk were significantly lower for the lighter bags. RELEVANCE TO INDUSTRY: The reduction in peak spine loading for the half-weight bags, particularly at the higher heights and when the feet were allowed to move could significantly reduce the injuries of masonry workers. However, there were trade-offs with cumulative loads that may minimize the reduced risk. Overall, given the limited amount of time lifting bags, the reduction of peak loads.

Depletion of the cellular levels of Bag-1 proteins attenuates phorbol ester-induced downregulation of I{kappa}B{alpha} and nuclear accumulation of NF-{kappa}B

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

Maier, Jana V., E-mail: Jana.maier@kit.edu; Volz, Yvonne; Berger, Caroline

2010-10-22

Research highlights: {yields}Bag-1 depletion only marginally affects the action of the glucocorticoid receptor but strongly regulates the activity of NF-{kappa}B. {yields}Bag-1 depletion attenuates phosphorylation and degradation of I{kappa}B{alpha} and nuclear accumulation of NF-{kappa}B p65 and p50. {yields}Bag-1 interacts with I{kappa}B{alpha} and partially restores I{kappa}B{alpha} and NF-{kappa}B activation in Bag-1 depleted cells. -- Abstract: Bag-1 consists in humans of four isoforms generated from the same RNA by alternative translation. Overexpression of single Bag-1 isoforms has identified Bag-1 as a negative regulator of action of many proteins including the glucocorticoid receptor (GR). Here we have analysed the ability of Bag-1 to regulatemore » the transrepression function of the GR. Silencing Bag-1 expression only marginally affects the transrepression action of the GR but decreased the action of the transcription factor NF-{kappa}B. Furthermore phosphorylation and degradation of the inhibitor protein I{kappa}B{alpha} and nuclear accumulation of p65 and p50 NF-{kappa}B proteins in response to phorbol ester was attenuated following Bag-1 depletion in HeLa cells. Reconstitution of Bag-1 in depleted cells partially restored I{kappa}B{alpha} and NF-{kappa}B activation. Knock-down of Bag-1 expression also did not significantly alter GR-mediated transactivation but affected the basal transcription of some of the target genes. Thus Bag-1 proteins function as regulators of the action of selective transcription factors.« less

Relative distance between tracers as a measure of diffusivity within moving aggregates

NASA Astrophysics Data System (ADS)

Pönisch, Wolfram; Zaburdaev, Vasily

2018-02-01

Tracking of particles, be it a passive tracer or an actively moving bacterium in the growing bacterial colony, is a powerful technique to probe the physical properties of the environment of the particles. One of the most common measures of particle motion driven by fluctuations and random forces is its diffusivity, which is routinely obtained by measuring the mean squared displacement of the particles. However, often the tracer particles may be moving in a domain or an aggregate which itself experiences some regular or random motion and thus masks the diffusivity of tracers. Here we provide a method for assessing the diffusivity of tracer particles within mobile aggregates by measuring the so-called mean squared relative distance (MSRD) between two tracers. We provide analytical expressions for both the ensemble and time averaged MSRD allowing for direct identification of diffusivities from experimental data.

Does the 'old bag' make a good 'wind bag'?: Comparison of four fabrics commonly used as exclusion bags in studies of pollination and reproductive biology.

PubMed

Neal, Paul R; Anderson, Gregory J

2004-05-01

Fabrics used in pollination bags may exclude pollen carried by biotic vectors, but have varying degrees of permeability to wind-borne pollen. The permeability of bags to wind-borne pollen may have important consequences in studies of pollination and reproductive biology. The permeability of four fabrics commonly used in the construction of pollination bags was examined. Deposition of wind-borne pollen on horizontally and vertically oriented microscope slides was assessed on slides enclosed in pollination bags, as well as on control slides. It was found that the permeability of fabrics to wind-borne pollen, as measured by deposition on both horizontally and vertically oriented slides, decreased with pore size. However, deposition on horizontal slides was always greater than on vertical slides for a given fabric; this could manifest itself as differential success of pollination of flowers in bags-dependent on flower orientation. Obviously, bags with mesh size smaller than most pollen grains are impermeable to pollen. However, material for such bags is very expensive. In addition, it was also observed that bags with even moderately small pore size, such as pores (approx. 200 microm) in twisted fibre cotton muslin, offered highly significant barriers to passage of wind-borne pollen. Such bags are sufficiently effective in most large-sample-size reproductive biology studies.

BAG3 down-modulation reduces anaplastic thyroid tumor growth by enhancing proteasome-mediated degradation of BRAF protein.

PubMed

Chiappetta, Gennaro; Basile, Anna; Arra, Claudio; Califano, Daniela; Pasquinelli, Rosa; Barbieri, Antonio; De Simone, Veronica; Rea, Domenica; Giudice, Aldo; Pezzullo, Luciano; De Laurenzi, Vincenzo; Botti, Gerardo; Losito, Simona; Conforti, Daniela; Turco, Maria Caterina

2012-01-01

Anaplastic thyroid tumors (ATC) express high levels of BAG3, a member of the BAG family of cochaperone proteins that is involved in regulating cell apoptosis through multiple mechanisms. The objective of the study was the investigation of the influence of B-cell lymphoma-2-associated athanogene 3 (BAG3) on ATC growth. We investigated the effects of BAG3 down-modulation, obtained by using a specific small interfering RNA, on in vitro and in vivo growth of the human ATC cell line 8505C. Because BRAF protein plays an important role in ATC cell growth, we analyzed the effects of BAG3 down-modulation on BRAF protein levels. Furthermore, by using a proteasome inhibitor, we verified whether BAG3-mediated regulation of BRAF levels involved a proteasome-dependent mechanism. BAG3 down-modulation significantly inhibits ATC growth in vitro and in vivo. BAG3 coimmunoprecipitates with BRAF protein, and its down-modulation results in a significant reduction of BRAF protein levels, which can be reverted by incubation with the proteasome inhibitor MG132. BAG3 protein sustains ATC growth in vitro and in vivo. The underlying molecular mechanism appears to rely on BAG3 binding to BRAF, thus protecting it from proteasome-dependent degradation. These results are in line with the reported ability of BAG3 to interfere with the proteasomal delivery of a number of other client proteins.

The anti-apoptotic BAG3 protein is expressed in lung carcinomas and regulates small cell lung carcinoma (SCLC) tumor growth.

PubMed

Chiappetta, Gennaro; Basile, Anna; Barbieri, Antonio; Falco, Antonia; Rosati, Alessandra; Festa, Michelina; Pasquinelli, Rosa; Califano, Daniela; Palma, Giuseppe; Costanzo, Raffaele; Barcaroli, Daniela; Capunzo, Mario; Franco, Renato; Rocco, Gaetano; Pascale, Maria; Turco, Maria Caterina; De Laurenzi, Vincenzo; Arra, Claudio

2014-08-30

BAG3, member the HSP70 co-chaperones family, has been shown to play a relevant role in the survival, growth and invasiveness of different tumor types. In this study, we investigate the expression of BAG3 in 66 specimens from different lung tumors and the role of this protein in small cell lung cancer (SCLC) tumor growth. Normal lung tissue did not express BAG3 while we detected the expression of BAG3 by immunohistochemistry in all the 13 squamous cell carcinomas, 13 adenocarcinomas and 4 large cell carcinomas. Furthermore, we detected BAG3 expression in 22 of the 36 SCLCs analyzed. The role on SCLC cell survival was determined by down-regulating BAG3 levels in two human SCLC cell lines, i.e. H69 and H446, in vitro and measuring cisplatin induced apoptosis. Indeed down-regulation of BAG3 determines increased cell death and sensitizes cells to cisplatin treatment. The effect of BAG3 down-regulation on tumor growth was also investigated in an in vivo xenograft model by treating mice with an adenovirus expressing a specific bag3 siRNA. Treatment with bag3 siRNA-Ad significantly reduced tumor growth and improved animal survival. In conclusion we show that a subset of SCLCs over express BAG3 that exerts an anti-apoptotic effect resulting in resistance to chemotherapy.

Effect of drug precursors and chemicals relevant to clandestine laboratory investigation on plastic bags used for collection and storage.

PubMed

Michelot, Harmonie; Fu, Shanlin; Stuart, Barbara; Shimmon, Ronald; Raymond, Tony; Crandell, Tony; Roux, Claude

2017-04-01

In the area of clandestine laboratory investigations, plastic bags are used to collect and store evidence, such as solvents, precursors, and other compounds usually employed for the manufacturing of drugs (although liquids may be stored in glass containers within the bags first). In this study, three different types of plastic bags were provided by the NSW Police Force and investigated for their suitability for evidence collection: two different types of low-density polyethylene (LDPE) bags and one type of polyvinyl chloride (PVC) bag. Three different experiments were carried out: (1) storing relevant chemicals in the bags for up to three months; (2) exposing the bags including their content to accelerated conditions using a weatherometer, and (3) simulating an expected real case scenario. This study indicates that drugs and related chemicals stored in plastic bags may lead to a change in the composition of the chemical and an alteration or degradation of the plastic bag. All experiments led to the same conclusion: the polyvinyl chloride bags appeared to be the most affected. LDPE bags seem to be more appropriate for routine use, although it has been established they are not suitable for the collection of liquids (unless pre-packaged in, for instance, a glass container). Copyright © 2017 Elsevier B.V. All rights reserved.

Urine drainage bags

MedlinePlus

... this page: //medlineplus.gov/ency/patientinstructions/000142.htm Urine drainage bags To use the sharing features on this page, please enable JavaScript. Urine drainage bags collect urine. Your bag will attach ...

76 FR 70965 - Polyethylene Retail Carrier Bags From Thailand: Correction to the Amended Final Results of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-16

... Bags From Thailand: Correction to the Amended Final Results of Antidumping Duty Administrative Review... bags from Thailand for the period August 1, 2009, through July 31, 2010. The notice did not include the... bags from Thailand. See Polyethylene Retail Carrier Bags From Thailand: Amended Final Results of...

49 CFR 178.519 - Standards for plastic film bags.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Standards for plastic film bags. 178.519 Section...-bulk Performance-Oriented Packaging Standards § 178.519 Standards for plastic film bags. (a) The identification code for a plastic film bag is 5H4. (b) Construction requirements for plastic film bags are as...

16 CFR 255.1 - General considerations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... an uncooked chicken in the oven roasting bag and places the bag in one oven. He then takes a chicken roasting bag from a second oven, removes from the bag what appears to be a perfectly cooked chicken, tastes... conduct. Example 4: A well-known celebrity appears in an infomercial for an oven roasting bag that...

49 CFR 173.166 - Air bag inflators, air bag modules and seat-belt pretensioners.

Code of Federal Regulations, 2011 CFR

2011-10-01

... an inflatable bag assembly. A seat-belt pre-tensioner contains similar hazardous materials and is... manufacturer has submitted each design type air bag inflator, air bag module, or seat-belt pretensioner to a... or pretensioner design type for which approval is sought and details on the complete package. The...

49 CFR 173.166 - Air bag inflators, air bag modules and seat-belt pretensioners.

Code of Federal Regulations, 2010 CFR

2010-10-01

... an inflatable bag assembly. A seat-belt pre-tensioner contains similar hazardous materials and is... manufacturer has submitted each design type air bag inflator, air bag module, or seat-belt pretensioner to a... or pretensioner design type for which approval is sought and details on the complete package. The...

49 CFR 173.166 - Air bag inflators, air bag modules and seat-belt pretensioners.

Code of Federal Regulations, 2012 CFR

2012-10-01

... an inflatable bag assembly. A seat-belt pre-tensioner contains similar hazardous materials and is... manufacturer has submitted each design type air bag inflator, air bag module, or seat-belt pretensioner to a... or pretensioner design type for which approval is sought and details on the complete package. The...

49 CFR 178.519 - Standards for plastic film bags.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Standards for plastic film bags. 178.519 Section...-bulk Performance-Oriented Packaging Standards § 178.519 Standards for plastic film bags. (a) The identification code for a plastic film bag is 5H4. (b) Construction requirements for plastic film bags are as...

49 CFR 178.519 - Standards for plastic film bags.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Standards for plastic film bags. 178.519 Section...-bulk Performance-Oriented Packaging Standards § 178.519 Standards for plastic film bags. (a) The identification code for a plastic film bag is 5H4. (b) Construction requirements for plastic film bags are as...

49 CFR 178.519 - Standards for plastic film bags.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Standards for plastic film bags. 178.519 Section...-bulk Performance-Oriented Packaging Standards § 178.519 Standards for plastic film bags. (a) The identification code for a plastic film bag is 5H4. (b) Construction requirements for plastic film bags are as...

78 FR 45880 - Hazardous Materials: Approval and Communication Requirements for the Safe Transportation of Air...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-30

... Communication Requirements for the Safe Transportation of Air Bag Inflators, Air Bag Modules, and Seat-Belt... Materials Regulations applicable to air bag inflators, air bag modules, and seat-belt pretensioners. The... amending the current approval and documentation requirements for a material classified as a UN3268 air bag...

BAG3 promotes stem cell-like phenotype in breast cancer by upregulation of CXCR4 via interaction with its transcript.

PubMed

Liu, Bao-Qin; Zhang, Song; Li, Si; An, Ming-Xin; Li, Chao; Yan, Jing; Wang, Jia-Mei; Wang, Hua-Qin

2017-07-13

BAG3 is an evolutionarily conserved co-chaperone expressed at high levels and has a prosurvival role in many tumor types. The current study reported that BAG3 was induced under specific floating culture conditions that enrich breast cancer stem cell (BCSC)-like cells in spheres. Ectopic BAG3 overexpression increased CD44 + /CD24 - CSC subpopulations, first-generation and second-generation mammosphere formation, indicating that BAG3 promotes CSC self-renewal and maintenance in breast cancer. We further demonstrated that mechanically, BAG3 upregulated CXCR4 expression at the post-transcriptional level. Further studies showed that BAG3 interacted with CXCR4 mRNA and promoted its expression via its coding and 3'-untranslational regions. BAG3 was also found to be positively correlated with CXCR4 expression and unfavorable prognosis in patients with breast cancer. Taken together, our data demonstrate that BAG3 promotes BCSC-like phenotype through CXCR4 via interaction with its transcript. Therefore, this study establishes BAG3 as a potential adverse prognostic factor and a therapeutic target of breast cancer.

Vertical Profiling of Soil Vapor Concentrations Using a New Passive Diffusion Sampler at a UST Site

EPA Science Inventory

Understanding the transport of volatile contaminants in soil gas, particularly those associated with underground storage tanks (USTs), requires a detailed knowledge about the depth-dependent distribution of chemical species in the subsurface. Traditional monitoring wells generall...

Analysis of BAG3 plasma concentrations in patients with acutely decompensated heart failure.

PubMed

Gandhi, Parul U; Gaggin, Hanna K; Belcher, Arianna M; Harisiades, Jamie E; Basile, Anna; Falco, Antonia; Rosati, Alessandra; Piscione, Federico; Januzzi, James L; Turco, M Caterina

2015-05-20

BCL-2-associated athanogene 3 (BAG3) is a protein implicated in the cardiomyocyte stress response and genesis of cardiomyopathy. Extracellular BAG3 is measurable in patients with heart failure (HF), but the relationship of BAG3 with HF prognosis is unclear. BAG3 plasma concentrations were measured in 39 acutely decompensated HF patients; the primary endpoint was death at 1 year. Baseline characteristics were compared by vital status and median BAG3 concentration. Correlation of BAG3 with left ventricular ejection fraction (LVEF) and other biomarkers was performed. Prognostic value was assessed using Cox proportional hazards regression and Kaplan-Meier analysis. At baseline, median BAG3 was significantly higher in decedents (N=11) than survivors (N=28; 1489 ng/mL versus 50 ng/mL; P=0.04); decedents also had worse renal function and higher median natriuretic peptide (NP) and sST2. BAG3 was not significantly correlated with NPs, mid-regional pro-adrenomedullin, sST2, or eGFR, however. Mortality was increased in patients with supra-median BAG3 (>336 ng/mL; 42.1% versus 15.0%, P=0.06). In age and LVEF-adjusted Cox proportional hazards, BAG3 remained a significant mortality predictor (HR=3.20; 95% CI=1.34-7.65; P=0.02); those with supra-median BAG3 had significantly shorter time-to-death (P=0.04). The stress response protein BAG3 is measurable in patients with ADHF and may be prognostic for death. Copyright © 2015 Elsevier B.V. All rights reserved.

Active transport of vesicles in neurons is modulated by mechanical tension.

PubMed

Ahmed, Wylie W; Saif, Taher A

2014-03-27

Effective intracellular transport of proteins and organelles is critical in cells, and is especially important for ensuring proper neuron functionality. In neurons, most proteins are synthesized in the cell body and must be transported through thin structures over long distances where normal diffusion is insufficient. Neurons transport subcellular cargo along axons and neurites through a stochastic interplay of active and passive transport. Mechanical tension is critical in maintaining proper function in neurons, but its role in transport is not well understood. To this end, we investigate the active and passive transport of vesicles in Aplysia neurons while changing neurite tension via applied strain, and quantify the resulting dynamics. We found that tension in neurons modulates active transport of vesicles by increasing the probability of active motion, effective diffusivity, and induces a retrograde bias. We show that mechanical tension modulates active transport processes in neurons and that external forces can couple to internal (subcellular) forces and change the overall transport dynamics.

Active transport of vesicles in neurons is modulated by mechanical tension

PubMed Central

Ahmed, Wylie W.; Saif, Taher A.

2014-01-01

Effective intracellular transport of proteins and organelles is critical in cells, and is especially important for ensuring proper neuron functionality. In neurons, most proteins are synthesized in the cell body and must be transported through thin structures over long distances where normal diffusion is insufficient. Neurons transport subcellular cargo along axons and neurites through a stochastic interplay of active and passive transport. Mechanical tension is critical in maintaining proper function in neurons, but its role in transport is not well understood. To this end, we investigate the active and passive transport of vesicles in Aplysia neurons while changing neurite tension via applied strain, and quantify the resulting dynamics. We found that tension in neurons modulates active transport of vesicles by increasing the probability of active motion, effective diffusivity, and induces a retrograde bias. We show that mechanical tension modulates active transport processes in neurons and that external forces can couple to internal (subcellular) forces and change the overall transport dynamics. PMID:24670781

Radiative transfer model for aerosols in infrared wavelengths for passive remote sensing applications.

PubMed

Ben-David, Avishai; Embury, Janon F; Davidson, Charles E

2006-09-10

A comprehensive analytical radiative transfer model for isothermal aerosols and vapors for passive infrared remote sensing applications (ground-based and airborne sensors) has been developed. The theoretical model illustrates the qualitative difference between an aerosol cloud and a chemical vapor cloud. The model is based on two and two/four stream approximations and includes thermal emission-absorption by the aerosols; scattering of diffused sky radiances incident from all sides on the aerosols (downwelling, upwelling, left, and right); and scattering of aerosol thermal emission. The model uses moderate resolution transmittance ambient atmospheric radiances as boundary conditions and provides analytical expressions for the information on the aerosol cloud that is contained in remote sensing measurements by using thermal contrasts between the aerosols and diffused sky radiances. Simulated measurements of a ground-based sensor viewing Bacillus subtilis var. niger bioaerosols and kaolin aerosols are given and discussed to illustrate the differences between a vapor-only model (i.e., only emission-absorption effects) and a complete model that adds aerosol scattering effects.

Internal quantum efficiency mapping analysis for a >20%-efficiency n-type bifacial solar cell with front-side emitter formed by BBr3 thermal diffusion

NASA Astrophysics Data System (ADS)

Simayi, Shalamujiang; Mochizuki, Toshimitsu; Kida, Yasuhiro; Shirasawa, Katsuhiko; Takato, Hidetaka

2017-10-01

This paper presents a large-area (239-cm2) high-efficiency n-type bifacial solar cell that is processed using tube-furnace thermal diffusion employing liquid sources BBr3 for the front-side boron emitter and POCl3 for the rear-side phosphorus back surface field (BSF). The SiN x /Al2O3 stack was applied to the front-side boron emitter as a passivation layer. Both the front and rear-side electrodes are obtained using screen-printed contacts with H-patterns. The resulting highest-efficiency solar cell has front- and rear-side efficiencies of 20.3 and 18.7%, respectively, while the corresponding bifaciality is up to 92%. Finally, the passivation quality of the SiN x /Al2O3 stack on the front-side boron emitter and rear-side phosphorus BSF is investigated and visualized by measuring the internal quantum efficiency mapping of the bifacial solar cell.

2'-Hydroxycinnamaldehyde induces apoptosis through HSF1-mediated BAG3 expression.

PubMed

Nguyen, Hai-Anh; Kim, Soo-A

2017-01-01

BAG3, a member of BAG co-chaperone family, is induced by stressful stimuli such as heat shock and heavy metals. Through interaction with various binding partners, BAG3 is thought to play a role in cellular adaptive responses against stressful conditions in normal and neoplastic cells. 2'-Hydroxycinnamaldehyde (HCA) is a natural derivative of cinnamaldehyde and has antitumor activity in various cancer cells. In the present study, for the first time, we identified that HCA induced BAG3 expression and BAG3-mediated apoptosis in cancer cells. The apoptotic cell death induced by HCA was demonstrated by caspase-7, -9 and PARP activation, and confirmed by Annexin V staining in both SW480 and SW620 colon cancer cells. Notably, both the mRNA and protein levels of BAG3 were largely induced by HCA in a dose- and time-dependent manner. By showing transcription factor HSF1 activation, we demonstrated that HCA induces the expression of BAG3 through HSF1 activation. More importantly, knockdown of BAG3 expression using siRNA largely inhibited HCA-induced apoptosis, suggesting that BAG3 is actively involved in HCA-induced cancer cell death. Considering the importance of the stress response mechanism in cancer progression, our results strongly suggest that BAG3 could be a potential target for anticancer therapy.

49 CFR 178.520 - Standards for textile bags.

Code of Federal Regulations, 2012 CFR

2012-10-01

... for a sift-proof textile bag; and (3) 5L3 for a water-resistant textile bag. (b) Construction requirements for textile bags are as follows: (1) The textiles used must be of good quality. The strength of... use of paper bonded to the inner surface of the bag by a water-resistant adhesive such as bitumen...

49 CFR 178.520 - Standards for textile bags.

Code of Federal Regulations, 2014 CFR

2014-10-01

... for a sift-proof textile bag; and (3) 5L3 for a water-resistant textile bag. (b) Construction requirements for textile bags are as follows: (1) The textiles used must be of good quality. The strength of... use of paper bonded to the inner surface of the bag by a water-resistant adhesive such as bitumen...

49 CFR 178.520 - Standards for textile bags.

Code of Federal Regulations, 2013 CFR

2013-10-01

... for a sift-proof textile bag; and (3) 5L3 for a water-resistant textile bag. (b) Construction requirements for textile bags are as follows: (1) The textiles used must be of good quality. The strength of... use of paper bonded to the inner surface of the bag by a water-resistant adhesive such as bitumen...

Plastic, Fantastic? What We Make. Science and Technology Education in Philippine Society.

ERIC Educational Resources Information Center

Philippines Univ., Quezon City. Inst. for Science and Mathematics Education Development.

This module provides information about plastics, focusing on the uses of plastic bags in particular. Topic areas considered include: (1) making plastic bags; (2) transparency of plastic bags; (3) plastic bags and food odors; (4) food containers (before and since plastics); and (5) disposing of plastic bags and other plastic products. The text is…

Industrial filter bags cleaned by high-frequency vibration: A concept

NASA Technical Reports Server (NTRS)

Kooy, A. V.

1973-01-01

System holds filter bag around fine-mesh metal screen and vibrates screen at its resonant frequency. This removes deposited byproducts and protects bag fibers from damaging forces. Because filter bags represent 20 to 40% of any industrial filtering investment, this method of extending bag life should be of interest to those responsible for plant maintenance.

76 FR 47641 - Pagani Automobili SpA; Denial of Application for Temporary Exemption From Advanced Air Bag...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-05

... regarding the availability of advanced air bag technology. Docket Nos. NHTSA-2011-0030-0006, NHTSA-2011-0006... advanced air bag technology.\\9\\ Accordingly, NHTSA concludes that the expense of advanced air bag... belief that advanced air bag technology has become more accessible to small volume manufacturers in...

BAG3 elevation inhibits cell proliferation via direct interaction with G6PD in hepatocellular carcinomas

PubMed Central

Kong, De-Hui; Li, Si; Du, Zhen-Xian; Liu, Chuan; Liu, Bao-Qin; Li, Chao; Zong, Zhi-Hong; Wang, Hua-Qin

2016-01-01

Bcl-2 associated athanogene 3 (BAG3) contains multiple protein-binding motifs to mediate potential interactions with chaperons and/or other proteins, which is possibly ascribed to the multifaceted functions assigned to BAG3. The current study demonstrated that BAG3 directly interacted with glucose 6 phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway (PPP). BAG3 suppressed the PPP flux, de novo DNA synthesis and cell growth in hepatocellular carcinomas (HCCs). The growth defect of HCCs with forced BAG3 expression can be rescued by enforced G6PD expression. However, BAG3 elevation did not cause a reduction in cellular NADPH concentrations, another main product of G6PD. In addition, supplement of nucleosides alone was sufficient to recover the growth defect mediated by BAG3 elevation. Collectively, the current study established a tumor suppressor-like function of BAG3 via direct interaction with G6PD in HCCs at the cellular level. PMID:26621836

BAG3 regulates epithelial-mesenchymal transition and angiogenesis in human hepatocellular carcinoma.

PubMed

Xiao, Heng; Cheng, Shaobing; Tong, Rongliang; Lv, Zheng; Ding, Chaofeng; Du, Chengli; Xie, Haiyang; Zhou, Lin; Wu, Jian; Zheng, Shusen

2014-03-01

Bcl2-associated athanogene 3 (BAG3) protein is a co-chaperone of heat-shock protein (Hsp) 70 and may regulate major physiological and pathophysiological processes. However, few reports have examined the role of BAG3 in human hepatocellular carcinoma (HCC). In this study, we show that BAG3 regulates epithelial-mesenchymal transition (EMT) and angiogenesis in HCC. BAG3 was overexpressed in HCC tissues and cell lines. BAG3 knockdown resulted in reduction in migration and invasion of HCC cells, which was linked to reversion of EMT by increasing E-cadherin expression and decreasing N-cadherin, vimentin and slug expression, as well as suppressing matrix metalloproteinase 2 (MMP-2) expression. In a xenograft tumorigenicity model, BAG3 knockdown effectively inhibited tumor growth and metastasis through reduction in CD34 and VEGF expression and reversal of the EMT pathway. In conclusion, BAG3 is associated with the invasiveness and angiogenesis in HCC, and the BAG3 gene may be a novel therapeutic approach against HCC.

BAG3 elevation inhibits cell proliferation via direct interaction with G6PD in hepatocellular carcinomas.

PubMed

Kong, De-Hui; Li, Si; Du, Zhen-Xian; Liu, Chuan; Liu, Bao-Qin; Li, Chao; Zong, Zhi-Hong; Wang, Hua-Qin

2016-01-05

Bcl-2 associated athanogene 3 (BAG3) contains multiple protein-binding motifs to mediate potential interactions with chaperons and/or other proteins, which is possibly ascribed to the multifaceted functions assigned to BAG3. The current study demonstrated that BAG3 directly interacted with glucose 6 phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway (PPP). BAG3 suppressed the PPP flux, de novo DNA synthesis and cell growth in hepatocellular carcinomas (HCCs). The growth defect of HCCs with forced BAG3 expression can be rescued by enforced G6PD expression. However, BAG3 elevation did not cause a reduction in cellular NADPH concentrations, another main product of G6PD. In addition, supplement of nucleosides alone was sufficient to recover the growth defect mediated by BAG3 elevation. Collectively, the current study established a tumor suppressor-like function of BAG3 via direct interaction with G6PD in HCCs at the cellular level.

Multiple-Instance Regression with Structured Data

NASA Technical Reports Server (NTRS)

Wagstaff, Kiri L.; Lane, Terran; Roper, Alex

2008-01-01

We present a multiple-instance regression algorithm that models internal bag structure to identify the items most relevant to the bag labels. Multiple-instance regression (MIR) operates on a set of bags with real-valued labels, each containing a set of unlabeled items, in which the relevance of each item to its bag label is unknown. The goal is to predict the labels of new bags from their contents. Unlike previous MIR methods, MI-ClusterRegress can operate on bags that are structured in that they contain items drawn from a number of distinct (but unknown) distributions. MI-ClusterRegress simultaneously learns a model of the bag's internal structure, the relevance of each item, and a regression model that accurately predicts labels for new bags. We evaluated this approach on the challenging MIR problem of crop yield prediction from remote sensing data. MI-ClusterRegress provided predictions that were more accurate than those obtained with non-multiple-instance approaches or MIR methods that do not model the bag structure.

Comparative efficacy of storage bags, storability and damage potential of bruchid beetle.

PubMed

Harish, G; Nataraja, M V; Ajay, B C; Holajjer, Prasanna; Savaliya, S D; Gedia, M V

2014-12-01

Groundnut during storage is attacked by number of stored grain pests and management of these insect pests particularly bruchid beetle, Caryedon serratus (Oliver) is of prime importance as they directly damage the pod and kernels. In this regard different storage bags that could be used and duration up to which we can store groundnut has been studied. Super grain bag recorded minimum number of eggs laid and less damage and minimum weight loss in pods and kernels in comparison to other storage bags. Analysis of variance for multiple regression models were found to be significant in all bags for variables viz, number of eggs laid, damage in pods and kernels, weight loss in pods and kernels throughout the season. Multiple comparison results showed that there was a high probability of eggs laid and pod damage in lino bag, fertilizer bag and gunny bag, whereas super grain bag was found to be more effective in managing the C. serratus owing to very low air circulation.

Diffusion and cellular uptake of drugs in live cells studied with surface-enhanced Raman scattering probes

NASA Astrophysics Data System (ADS)

Bálint, Štefan; Rao, Satish; Sánchez, Mónica Marro; Huntošová, Veronika; Miškovský, Pavol; Petrov, Dmitri

2010-03-01

An understanding of the mechanisms of drug diffusion and uptake through cellular membranes is critical for elucidating drug action and in the development of effective drug delivery systems. We study these processes for emodin, a potential anticancer drug, in live cancer cells using surface-enhanced Raman scattering. Micrometer-sized silica beads covered by nanosized silver colloids are passively embedded into the cell and used as sensors of the drug. We demonstrate that the technique offers distinct advantages: the possibility to study the kinetics of drug diffusion through the cellular membrane toward specific cell organelles, the detection of lower drug concentrations compared to fluorescence techniques, and less damage imparted on the cell.

Low-temperature fabrication of an HfO2 passivation layer for amorphous indium-gallium-zinc oxide thin film transistors using a solution process.

PubMed

Hong, Seonghwan; Park, Sung Pyo; Kim, Yeong-Gyu; Kang, Byung Ha; Na, Jae Won; Kim, Hyun Jae

2017-11-24

We report low-temperature solution processing of hafnium oxide (HfO 2 ) passivation layers for amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs). At 150 °C, the hafnium chloride (HfCl 4 ) precursor readily hydrolyzed in deionized (DI) water and transformed into an HfO 2 film. The fabricated HfO 2 passivation layer prevented any interaction between the back surface of an a-IGZO TFT and ambient gas. Moreover, diffused Hf 4+ in the back-channel layer of the a-IGZO TFT reduced the oxygen vacancy, which is the origin of the electrical instability in a-IGZO TFTs. Consequently, the a-IGZO TFT with the HfO 2 passivation layer exhibited improved stability, showing a decrease in the threshold voltage shift from 4.83 to 1.68 V under a positive bias stress test conducted over 10,000 s.

Testing odorants recovery from a novel metallized fluorinated ethylene propylene gas sampling bag.

PubMed

Zhu, Wenda; Koziel, Jacek A; Cai, Lingshuang; Wright, Donald; Kuhrt, Fred

2015-12-01

Industry-standard Tedlar bags for odor sample collection from confined animal feeding operations (CAFOs) have been challenged by the evidence of volatile organic compound (VOC) losses and background interferences. Novel impermeable aluminum foil with a thin layer of fluorinated ethylene propylene (FEP) film on the surface that is in contact with a gas sample was developed to address this challenge. In this research, Tedlar and metallized FEP bags were compared for (a) recoveries of four characteristic CAFO odorous VOCs (ethyl mercaptan, butyric acid, isovaleric acid and p-cresol) after 30 min and 24 hr sample storage time and for (b) chemical background interferences. All air sampling and analyses were performed with solid-phase microextraction (SPME) followed by gas chromatography-mass spectroscopy (GC-MS). Mean target gas sample recoveries from metallized FEP bags were 25.9% and 28.0% higher than those in Tedlar bags, for 30 min and 24 hr, respectively. Metallized FEP bags demonstrated the highest p-cresol recoveries after 30-min and 24-hr storage, 96.1±44.5% and 44.8±10.2%, respectively, among different types of sampling bags reported in previous studies. However, a higher variability was observed for p-cresol recovery with metallized FEP bags. A 0% recovery of ethyl mercaptan was observed with Tedlar bags after 24-hr storage, whereas an 85.7±7.4% recovery was achieved with metallized FEP bags. Recoveries of butyric and isovaleric acids were similar for both bag types. Two major impurities in Tedlar bags' background were identified as N,N-dimethylacetamide and phenol, while backgrounds of metallized FEP bags were significantly cleaner. Reusability of metallized FEP bags was tested. Caution is advised when using polymeric materials for storage of livestock-relevant odorous volatile organic compounds. The odorants loss with storage time confirmed that long-term storage in whole-air form is ill advised. A focused short-term odor sample containment should be biased toward the most inert material available relative to the highest impact target odorant. Metallized FEP was identified as such a material to p-cresol as the highest impact odorant from confined animal feeding operations. Metallized FEP bags have much cleaner background than commercial Tedlar bags do. Significantly higher recoveries of methyl mercaptan and p-cresol were also observed with metallized FEP bags.

Uptake of L-nicotine and of 6-hydroxy-L-nicotine by Arthrobacter nicotinovorans and by Escherichia coli is mediated by facilitated diffusion and not by passive diffusion or active transport.

PubMed

Ganas, Petra; Brandsch, Roderich

2009-06-01

The mechanism by which l-nicotine is taken up by bacteria that are able to grow on it is unknown. Nicotine degradation by Arthrobacter nicotinovorans, a Gram-positive soil bacterium, is linked to the presence of the catabolic megaplasmid pAO1. l-[(14)C]Nicotine uptake assays with A. nicotinovorans showed transport of nicotine across the cell membrane to be energy-independent and saturable with a K(m) of 6.2+/-0.1 microM and a V(max) of 0.70+/-0.08 micromol min(-1) (mg protein)(-1). This is in accord with a mechanism of facilitated diffusion, driven by the nicotine concentration gradient. Nicotine uptake was coupled to its intracellular degradation, and an A. nicotinovorans strain unable to degrade nicotine (pAO1(-)) showed no nicotine import. However, when the nicotine dehydrogenase genes were expressed in this strain, import of l-[(14)C]nicotine took place. A. nicotinovorans pAO1(-) and Escherichia coli were also unable to import 6-hydroxy-l-nicotine, but expression of the 6-hydroxy-l-nicotine oxidase gene allowed both bacteria to take up this compound. l-Nicotine uptake was inhibited by d-nicotine, 6-hydroxy-l-nicotine and 2-amino-l-nicotine, which may indicate transport of these nicotine derivatives by a common permease. Attempts to correlate nicotine uptake with pAO1 genes possessing similarity to amino acid transporters failed. In contrast to the situation at the blood-brain barrier, nicotine transport across the cell membrane by these bacteria was not by passive diffusion or active transport but by facilitated diffusion.

Direct numerical simulation of turbulent mixing at very low Schmidt number with a uniform mean gradient

NASA Astrophysics Data System (ADS)

Yeung, P. K.; Sreenivasan, K. R.

2014-01-01

In a recent direct numerical simulation (DNS) study [P. K. Yeung and K. R. Sreenivasan, "Spectrum of passive scalars of high molecular diffusivity in turbulent mixing," J. Fluid Mech. 716, R14 (2013)] with Schmidt number as low as 1/2048, we verified the essential physical content of the theory of Batchelor, Howells, and Townsend ["Small-scale variation of convected quantities like temperature in turbulent fluid. 2. The case of large conductivity," J. Fluid Mech. 5, 134 (1959)] for turbulent passive scalar fields with very strong diffusivity, decaying in the absence of any production mechanism. In particular, we confirmed the existence of the -17/3 power of the scalar spectral density in the so-called inertial-diffusive range. In the present paper, we consider the DNS of the same problem, but in the presence of a uniform mean gradient, which leads to the production of scalar fluctuations at (primarily) the large scales. For the parameters of the simulations, the presence of the mean gradient alters the physics of mixing fundamentally at low Peclet numbers. While the spectrum still follows a -17/3 power law in the inertial-diffusive range, the pre-factor is non-universal and depends on the magnitude of the mean scalar gradient. Spectral transfer is greatly reduced in comparison with those for moderately and weakly diffusive scalars, leading to several distinctive features such as the absence of dissipative anomaly and a new balance of terms in the spectral transfer equation for the scalar variance, differing from the case of zero gradient. We use the DNS results to present an alternative explanation for the observed scaling behavior, and discuss a few spectral characteristics in detail.

The Portuguese plastic carrier bag tax: The effects on consumers' behavior.

PubMed

Martinho, Graça; Balaia, Natacha; Pires, Ana

2017-03-01

Marine litter from lightweight plastic bags is a global problem that must be solved. A plastic bag tax was implemented in February 2015 to reduce the consumption of plastic grocery bags in Portugal and in turn reduce the potential contribution to marine litter. This study analyzes the effect of the plastic bag tax on consumer behavior to learn how it was received and determine the perceived effectiveness of the tax 4months after its implementation. In addition, the study assessed how proximity to coastal areas could influence behaviors and opinions. The results showed a 74% reduction of plastic bag consumption with a simultaneously 61% increase of reusable plastic bags after the tax was implemented. Because plastic bags were then reused for shopping instead of garbage bags, however, the consumption of garbage bags increased by 12%. Although reduction was achieved, the tax had no effect on the perception of marine litter or the impact of plastic bags on environment and health. The majority of respondents agree with the tax but view it as an extra revenue to the State. The distance to the coast had no meaningful influence on consumer behavior or on the perception of the tax. Although the tax was able to promote the reduction of plastics, the role of hypermarkets and supermarkets in providing alternatives through the distribution of reusable plastic bags was determinant to ensuring the reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Outer-membrane translocation of bulky small molecules by passive diffusion

PubMed Central

van den Berg, Bert; Prathyusha Bhamidimarri, Satya; Dahyabhai Prajapati, Jigneshkumar; Kleinekathöfer, Ulrich; Winterhalter, Mathias

2015-01-01

The outer membrane (OM) of gram-negative bacteria forms a protective layer around the cell that serves as a permeability barrier to prevent unrestricted access of noxious substances. The permeability barrier of the OM results partly from the limited pore diameters of OM diffusion channels. As a consequence, there is an “OM size-exclusion limit,” and the uptake of bulky molecules with molecular masses of more than ∼600 Da is thought to be mediated by TonB-dependent, active transporters. Intriguingly, the OM protein CymA from Klebsiella oxytoca does not depend on TonB but nevertheless mediates efficient OM passage of cyclodextrins with diameters of up to ∼15 Å. Here we show, by using X-ray crystallography, molecular dynamics simulations, and single-channel electrophysiology, that CymA forms a monomeric 14-stranded β-barrel with a large pore that is occluded on the periplasmic side by the N-terminal 15 residues of the protein. Representing a previously unidentified paradigm in OM transport, CymA mediates the passive diffusion of bulky molecules via an elegant transport mechanism in which a mobile element formed by the N terminus acts as a ligand-expelled gate to preserve the permeability barrier of the OM. PMID:26015567

Diffusion, spread, and migration of botulinum toxin.

PubMed

Ramirez-Castaneda, Juan; Jankovic, Joseph; Comella, Cynthia; Dashtipour, Khashayar; Fernandez, Hubert H; Mari, Zoltan

2013-11-01

Botulinum toxin (BoNT) is an acetylcholine release inhibitor and a neuromuscular blocking agent used for the treatment of a variety of neurologic and medical conditions. The efficacy and safety of BoNT depends on accurate selection and identification of intended targets but also may be determined by other factors, including physical spread of the molecule from the injection site, passive diffusion, and migration to distal sites via axonal or hematogenous transport. The passive kinetic dispersion of the toxin away from the injection site in a gradient-dependent manner may also play a role in toxin spread. In addition to unique properties of the various BoNT products, volume and dilution may also influence local and systemic distribution of BoNT. Most of the local and remote complications of BoNT injections are thought to be due to unwanted spread or diffusion of the toxin's biologic activity into adjacent and distal muscles. Despite widespread therapeutic and cosmetic use of BoNT over more than three decades, there is a remarkable paucity of published data on the mechanisms of distribution and its effects on clinical outcomes. The primary aim of this article is to critically review the available experimental and clinical literature and place it in the practical context. © 2013 International Parkinson and Movement Disorder Society.

Hydrogen passivation of n+p and p+n heteroepitaxial InP solar cell structures

NASA Technical Reports Server (NTRS)

Chatterjee, B.; Ringel, S. A.; Hoffman, R., Jr.

1995-01-01

High-efficiency, heteroepitaxial (HE) InP solar cells, grown on GaAs, Si or Ge substrates, are desirable for their mechanically strong, light-weight and radiation-hard properties. However, dislocations, caused by lattice mismatch, currently limit the performance of the HE cells. This occurs through shunting paths across the active photovoltaic junction and by the formation of deep levels. In previous work we have demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of dislocations in specially designed HE InP test structures. In this work, we present the first report of successful hydrogen passivation in actual InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in HE n+n InP cell structures from as-grown values of approximately 10(exp 15)/cm(exp -3), down to 1-2 x 10(exp 13)/cm(exp -3). The deep levels in the p-type base region of the cell structure match those of our earlier p-type test structures, which were attributed to dislocations or related point defect complexes. All dopants were successfully reactivated by a 400 C, 5 minute anneal with no detectable activation of deep levels. I-V analysis indicated a subsequent approximately 10 fold decrease in reverse leakage current at -1 volt reverse bias, and no change in the forward biased series resistance of the cell structure which indicates complete reactivation of the n+ emitter. Furthermore, electrochemical C-V profiling indicates greatly enhanced passivation depth, and hence hydrogen diffusion, for heteroepitaxial structures when compared with identically processed homoepitaxial n+p InP structures. An analysis of hydrogen diffusion in dislocated InP will be discussed, along with comparisons of passivation effectiveness for n+p versus p+n heteroepitaxial cell configurations. Preliminary hydrogen-passivated HE InP cell results will also be presented.

Friction Regimes of Water-Lubricated Diamond (111): Role of Interfacial Ether Groups and Tribo-Induced Aromatic Surface Reconstructions

NASA Astrophysics Data System (ADS)

Kuwahara, Takuya; Moras, Gianpietro; Moseler, Michael

2017-09-01

Large-scale quantum molecular dynamics of water-lubricated diamond (111) surfaces in sliding contact reveals multiple friction regimes. While water starvation causes amorphization of the tribological interface, small H2O traces are sufficient to preserve crystallinity. This can result in high friction due to cold welding via ether groups or in ultralow friction due to aromatic surface passivation triggered by tribo-induced Pandey reconstruction. At higher water coverage, Grotthuss-type diffusion and H2O dissociation yield dense H /OH surface passivation leading to another ultralow friction regime.

BAG3 promotes chondrosarcoma progression by upregulating the expression of β-catenin.

PubMed

Shi, Huijuan; Chen, Wenfang; Dong, Yu; Lu, Xiaofang; Zhang, Wenhui; Wang, Liantang

2018-04-01

To investigate the roles of B‑cell lymphoma‑2 associated athanogene 3 (BAG3) in human chondrosarcoma and the potential mechanisms, the expression levels of BAG3 were detected in the present study, and the associations between BAG3 and clinical pathological parameters, clinical stage as well as the survival of patients were analyzed. The present study detected BAG3 mRNA and protein expression in the normal cartilage cell line HC‑a and in SW1353 chondrosarcoma cells by reverse transcription‑quantitative polymerase chain reaction and western blot analysis. The BAG3 protein expression in 59 cases of chondrosarcoma, 30 patients with endogenous chondroma and 8 cases of normal cartilage was semi-quantitatively analyzed using the immunohistochemical method. In addition, the BAG3 protein expression level, the clinical pathological parameters, clinical stage and the survival time of patients with chondrosarcoma were analyzed. The plasmid transfection method was employed to upregulate the expression BAG3 and small RNA interference to downregulate the expression of BAG3 in SW1353 cells. The expression levels of BAG3 protein and mRNA were significantly increased in the chondrosarcoma cell line when compared with the normal cartilage cell line. The immunohistochemistry results indicated that BAG3 protein was overexpressed in the tissue of human chondrosarcoma. Statistical analysis showed that the expression level of BAG3 was significantly increased in the different Enneking staging of patients with chondrosarcoma and Tumor staging, and there were no statistical differences in age, gender, histological classification and tumor size. In the in vitro experiments, the data revealed that BAG3 significantly promoted chondrosarcoma cell proliferation, colony‑formation, migration and invasion; however, it inhibited chondrosarcoma cell apoptosis. It was observed that BAG3 upregulated β‑catenin expression at the mRNA and protein levels. In addition, BAG3 induced the expression of runt‑related transcription factor 2 (RUNX2) in chondrosarcoma cells by upregulating β‑catenin. These clinical analyses revealed a positive association between β‑catenin and BAG3 in chondrosarcoma tumors. BAG3 was significantly increased in chondrosarcoma cells and tissues compared with the normal cartilage cells, tissue and cartilage benign tumors. Thus, BAG3 may serve as an oncogene in the development of chondrosarcoma via the induction of RUNX2 expression. The results of the present study contribute to further research on the biological development of chondrosarcoma.

40 CFR 63.1184 - What do I need to know about the design specifications, installation, and operation of a bag leak...

Code of Federal Regulations, 2010 CFR

2010-07-01

... design specifications, installation, and operation of a bag leak detection system? 63.1184 Section 63... bag leak detection system? A bag leak detection system must meet the following requirements: (a) The bag leak detection system must be certified by the manufacturer to be capable of detecting PM...

49 CFR 178.521 - Standards for paper bags.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Standards for paper bags. 178.521 Section 178.521...-Oriented Packaging Standards § 178.521 Standards for paper bags. (a) The following are identification codes for paper bags: (1) 5M1 for a multi-wall paper bag; and (2) 5M2 for a multi-wall water-resistant paper...

49 CFR 178.521 - Standards for paper bags.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Standards for paper bags. 178.521 Section 178.521...-bulk Performance-Oriented Packaging Standards § 178.521 Standards for paper bags. (a) The following are identification codes for paper bags: (1) 5M1 for a multi-wall paper bag; and (2) 5M2 for a multi-wall water...

75 FR 59674 - Make Inoperative Exemptions; Vehicle Modifications To Accommodate People With Disabilities, Side...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-28

... that many vehicles will depend on side impact air bag technology to meet all of the injury criteria of... ``lead to the installation of new technologies, such as side curtain air bags and torso side air bags... is side air bag technology incorporated in the vehicle's roof rail (side air bag curtain), door, and...

Evaluation of advanced air bag deployment algorithm performance using event data recorders.

PubMed

Gabler, Hampton C; Hinch, John

2008-10-01

This paper characterizes the field performance of occupant restraint systems designed with advanced air bag features including those specified in the US Federal Motor Vehicle Safety Standard (FMVSS) No. 208 for advanced air bags, through the use of Event Data Recorders (EDRs). Although advanced restraint systems have been extensively tested in the laboratory, we are only beginning to understand the performance of these systems in the field. Because EDRs record many of the inputs to the advanced air bag control module, these devices can provide unique insights into the characteristics of field performance of air bags. The study was based on 164 advanced air bag cases extracted from NASS/CDS 2002-2006 with associated EDR data. In this dataset, advanced driver air bags were observed to deploy with a 50% probability at a longitudinal delta-V of 9 mph for the first stage, and at 26 mph for both inflator stages. In general, advanced air bag performance was as expected, however, the study identified cases of air bag deployments at delta-Vs as low as 3-4 mph, non-deployments at delta-Vs over 26 mph, and possible delayed air bag deployments.

Evaluation of Advanced Air Bag Deployment Algorithm Performance using Event Data Recorders

PubMed Central

Gabler, Hampton C.; Hinch, John

2008-01-01

This paper characterizes the field performance of occupant restraint systems designed with advanced air bag features including those specified in the US Federal Motor Vehicle Safety Standard (FMVSS) No. 208 for advanced air bags, through the use of Event Data Recorders (EDRs). Although advanced restraint systems have been extensively tested in the laboratory, we are only beginning to understand the performance of these systems in the field. Because EDRs record many of the inputs to the advanced air bag control module, these devices can provide unique insights into the characteristics of field performance of air bags. The study was based on 164 advanced air bag cases extracted from NASS/CDS 2002-2006 with associated EDR data. In this dataset, advanced driver air bags were observed to deploy with a 50% probability at a longitudinal delta-V of 9 mph for the first stage, and at 26 mph for both inflator stages. In general, advanced air bag performance was as expected, however, the study identified cases of air bag deployments at delta-Vs as low as 3-4 mph, non-deployments at delta-Vs over 26 mph, and possible delayed air bag deployments. PMID:19026234

In vitro blood and fibroblast responses to BisGMA-TEGDMA/bioactive glass composite implants.

PubMed

Abdulmajeed, Aous A; Kokkari, Anne K; Käpylä, Jarmo; Massera, Jonathan; Hupa, Leena; Vallittu, Pekka K; Närhi, Timo O

2014-01-01

This in vitro study was designed to evaluate both blood and human gingival fibroblast responses to bisphenol A-glycidyl methacrylate-triethyleneglycol dimethacrylate (BisGMA-TEGDMA)/bioactive glass (BAG) composite, aimed to be used as composite implant abutment surface modifier. Three different types of substrates were investigated: (a) plain polymer (BisGMA 50 wt%-TEGDMA 50 wt%), (b) BAG-composite (50 wt% polymer + 50 wt% fraction of BAG-particles, <50 μm), and (c) plain BAG plates (100 wt% BAG). The blood response, including the blood-clotting ability and platelet adhesion morphology were evaluated. Human gingival fibroblasts were plated and cultured on the experimental substrates for up to 10 days, then the cell proliferation rate was assessed using AlamarBlue assay™. The BAG-composite and plain BAG substrates had a shorter clotting time than plain polymer substrates. Platelet activation and aggregation were most extensive, qualitatively, on BAG-composite. Analysis of the normalized cell proliferation rate on the different surfaces showed some variations throughout the experiment, however, by day 10 the BAG-composite substrate showed the highest (P < 0.001) cell proliferation rate. In conclusion, the presence of exposed BAG-particles enhances fibroblast and blood responses on composite surfaces in vitro.

BAG3 directly stabilizes Hexokinase 2 mRNA and promotes aerobic glycolysis in pancreatic cancer cells.

PubMed

An, Ming-Xin; Li, Si; Yao, Han-Bing; Li, Chao; Wang, Jia-Mei; Sun, Jia; Li, Xin-Yu; Meng, Xiao-Na; Wang, Hua-Qin

2017-12-04

Aerobic glycolysis, a phenomenon known historically as the Warburg effect, is one of the hallmarks of cancer cells. In this study, we characterized the role of BAG3 in aerobic glycolysis of pancreatic ductal adenocarcinoma (PDAC) and its molecular mechanisms. Our data show that aberrant expression of BAG3 significantly contributes to the reprogramming of glucose metabolism in PDAC cells. Mechanistically, BAG3 increased Hexokinase 2 (HK2) expression, the first key enzyme involved in glycolysis, at the posttranscriptional level. BAG3 interacted with HK2 mRNA, and the degree of BAG3 expression altered recruitment of the RNA-binding proteins Roquin and IMP3 to the HK2 mRNA. BAG3 knockdown destabilized HK2 mRNA via promotion of Roquin recruitment, whereas BAG3 overexpression stabilized HK2 mRNA via promotion of IMP3 recruitment. Collectively, our results show that BAG3 promotes reprogramming of glucose metabolism via interaction with HK2 mRNA in PDAC cells, suggesting that BAG3 may be a potential target in the aerobic glycolysis pathway for developing novel anticancer agents. © 2017 An et al.

BAG3 promotes proliferation of ovarian cancer cells via post-transcriptional regulation of Skp2 expression.

PubMed

Yan, Jing; Liu, Chuan; Jiang, Jing-Yi; Liu, Hans; Li, Chao; Li, Xin-Yu; Yuan, Ye; Zong, Zhi-Hong; Wang, Hua-Qin

2017-10-01

Bcl-2 associated athanogene 3 (BAG3) contains a modular structure, through which BAG3 interacts with a wide range of proteins, thereby affording its capacity to regulate multifaceted biological processes. BAG3 is often highly expressed and functions as a pro-survival factor in many cancers. However, the oncogenic potential of BAG3 remains not fully understood. The cell cycle regulator, S-phase kinase associated protein 2 (Skp2) is increased in various cancers and plays an important role in tumorigenesis. The current study demonstrated that BAG3 promoted proliferation of ovarian cancer cells via upregulation of Skp2. BAG3 stabilized Skp2 mRNA via its 3'-untranslated region (UTR). The current study demonstrated that BAG3 interacted with Skp2 mRNA. In addition, miR-21-5p suppressed Skp2 expression, which was compromised by forced BAG3 expression. These results indicated that at least some oncogenic functions of BAG3 were mediated through posttranscriptional regulation of Skp2 via antagonizing suppressive action of miR-21-5p in ovarian cancer cells. Copyright © 2017 Elsevier B.V. All rights reserved.

BAG3 promotes stem cell-like phenotype in breast cancer by upregulation of CXCR4 via interaction with its transcript

PubMed Central

Liu, Bao-Qin; Zhang, Song; Li, Si; An, Ming-Xin; Li, Chao; Yan, Jing; Wang, Jia-Mei; Wang, Hua-Qin

2017-01-01

BAG3 is an evolutionarily conserved co-chaperone expressed at high levels and has a prosurvival role in many tumor types. The current study reported that BAG3 was induced under specific floating culture conditions that enrich breast cancer stem cell (BCSC)-like cells in spheres. Ectopic BAG3 overexpression increased CD44+/CD24− CSC subpopulations, first-generation and second-generation mammosphere formation, indicating that BAG3 promotes CSC self-renewal and maintenance in breast cancer. We further demonstrated that mechanically, BAG3 upregulated CXCR4 expression at the post-transcriptional level. Further studies showed that BAG3 interacted with CXCR4 mRNA and promoted its expression via its coding and 3′-untranslational regions. BAG3 was also found to be positively correlated with CXCR4 expression and unfavorable prognosis in patients with breast cancer. Taken together, our data demonstrate that BAG3 promotes BCSC-like phenotype through CXCR4 via interaction with its transcript. Therefore, this study establishes BAG3 as a potential adverse prognostic factor and a therapeutic target of breast cancer. PMID:28703799

Snap-lock bags with red band: A study of manufacturing characteristics, thermal and chemical properties.

PubMed

Sim, Yvonne Hui Ying; Koh, Alaric C W; Lim, Shing Min; Yew, Sok Yee

2015-10-01

Drug packaging is commonly submitted to the Forensic Chemistry and Physics Laboratory of the Health Sciences Authority, Singapore, for examination. The drugs seized are often packaged in plastic bags. These bags are examined for linkages to provide law enforcement with useful associations between the traffickers and drug abusers. The plastic bags submitted may include snap-lock bags, some with a red band located above the snap-lock closure and some without. Current techniques for examination involve looking at the physical characteristics (dimensions, thickness and polarising patterns) and manufacturing marks of these bags. In cases where manufacturing marks on the main body of the bags are poor or absent, the manufacturing characteristics present on the red band can be examined. A study involving approximately 1000 bags was conducted to better understand the variations in the manufacturing characteristics of the red band. This understanding is crucial in helping to determine associations/eliminations between bags. Two instrumental techniques, namely differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were explored to evaluate the effectiveness of examining the chemical composition to discriminate the bags. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Volatile organic compounds at two oil and natural gas production well pads in Colorado and Texas using passive samplers.

PubMed

Eisele, Adam P; Mukerjee, Shaibal; Smith, Luther A; Thoma, Eben D; Whitaker, Donald A; Oliver, Karen D; Wu, Tai; Colon, Maribel; Alston, Lillian; Cousett, Tamira A; Miller, Michael C; Smith, Donald M; Stallings, Casson

2016-04-01

A pilot study was conducted in application of the U.S. Environmental Protection Agency (EPA) Methods 325A/B variant for monitoring volatile organic compounds (VOCs) near two oil and natural gas (ONG) production well pads in the Texas Barnett Shale formation and Colorado Denver-Julesburg Basin (DJB), along with a traffic-dominated site in downtown Denver, CO. As indicated in the EPA method, VOC concentrations were measured for 14-day sampling periods using passive-diffusive tube samplers with Carbopack X sorbent at fenceline perimeter and other locations. VOCs were significantly higher at the DJB well pad versus the Barnett well pad and were likely due to higher production levels at the DJB well pad during the study. Benzene and toluene were significantly higher at the DJB well pad versus downtown Denver. Except for perchloroethylene, VOCs measured at passive sampler locations (PSs) along the perimeter of the Barnett well pad were significantly higher than PSs farther away. At the DJB well pad, most VOC concentrations, except perchloroethylene, were significantly higher prior to operational changes than after these changes were made. Though limited, the results suggest passive samplers are precise (duplicate precision usually ≤10%) and that they can be useful to assess spatial gradients and operational conditions at well pad locations over time-integrated periods. Recently enacted EPA Methods 325A/B use passive-diffusive tube samplers to measure benzene at multiple fenceline locations at petrochemical refineries. This pilot study presents initial data demonstrating the utility of Methods 325A/B for monitoring at ONG facilities. Measurements revealed elevated concentrations reflective of production levels and spatial gradients of VOCs relative to source proximity at the Barnett well pad, as well as operational changes at the DJB well pad. Though limited, these findings indicate that Methods 325A/B can be useful in application to characterize VOCs at well pad boundaries.

The effect of air bags on pregnancy outcomes in Washington State: 2002-2005.

PubMed

Schiff, Melissa A; Mack, Christopher D; Kaufman, Robert P; Holt, Victoria L; Grossman, David C

2010-01-01

To estimate whether air-bag deployment is associated with an increased risk of adverse pregnancy outcomes. We performed a retrospective cohort study to assess the effect of air-bag availability and air-bag deployment on the risk of adverse pregnancy outcomes among pregnant, front-seat occupants in motor vehicle crashes in Washington State. Pregnant women involved in motor vehicle crashes were identified by linking birth and fetal death certificate data with Washington State Patrol crash data, which reported air-bag availability and deployment. We calculated relative risks (RRs) of adverse maternal and perinatal outcomes and 95% confidence intervals (CIs) using Poisson regression, adjusted for maternal age, seatbelt use, and vehicle model year. We found no increased risk of adverse maternal or perinatal pregnancy outcomes among occupants of air-bag-equipped vehicles in all collisions (n=2,207) compared with those in vehicles without air bags (n=1,141). Among crashes in which air-bag deployment would be likely, we found a nonsignificant 70% increased risk of preterm labor (RR 1.7, 95% CI 0.9-3.2) and a nonsignificant threefold increased risk (RR 3.1, 95% CI 0.4-22.1) of fetal death among occupants in vehicles with air-bag deployment compared with occupants in vehicles without air bags, although fetal death results were limited by small numbers (2/198 [1.0%] in pregnant women whose air bags deployed; 2/622 [0.3%] in pregnant women whose air bags did not deploy). Our findings provide clinicians with evidence to advise women that air bags do not seem to elevate risk of most potential adverse outcomes during pregnancy. II.

BAG3 Expression in Glioblastoma Cells Promotes Accumulation of Ubiquitinated Clients in an Hsp70-dependent Manner*

PubMed Central

Gentilella, Antonio; Khalili, Kamel

2011-01-01

Disposal of damaged proteins and protein aggregates is a prerequisite for the maintenance of cellular homeostasis and impairment of this disposal can lead to a broad range of pathological conditions, most notably in brain-associated disorders including Parkinson and Alzheimer diseases, and cancer. In this respect, the Protein Quality Control (PQC) pathway plays a central role in the clearance of damaged proteins. The Hsc/Hsp70-co-chaperone BAG3 has been described as a new and critical component of the PQC in several cellular contexts. For example, the expression of BAG3 in the rodent brain correlates with the engagement of protein degradation machineries in response to proteotoxic stress. Nevertheless, little is known about the molecular events assisted by BAG3. Here we show that ectopic expression of BAG3 in glioblastoma cells leads to the activation of an HSF1-driven stress response, as attested by transcriptional activation of BAG3 and Hsp70. BAG3 overexpression determines an accumulation of ubiquitinated proteins and this event requires the N-terminal region, WW domain of BAG3 and the association of BAG3 with Hsp70. The ubiquitination mainly occurs on BAG3-client proteins and the inhibition of proteasomal activity results in a further accumulation of ubiquitinated clients. At the cellular level, overexpression of BAG3 in glioblastoma cell lines, but not in non-glial cells, results in a remarkable decrease in colony formation capacity and this effect is reverted when the binding of BAG3 to Hsp70 is impaired. These observations provide the first evidence for an involvement of BAG3 in the ubiquitination and turnover of its partners. PMID:21233200

Proteomic Analysis Reveals a Role for Bcl2-associated Athanogene 3 and Major Vault Protein in Resistance to Apoptosis in Senescent Cells by Regulating ERK1/2 Activation*

PubMed Central

Pasillas, Martina P.; Shields, Sarah; Reilly, Rebecca; Strnadel, Jan; Behl, Christian; Park, Robin; Yates, John R.; Klemke, Richard; Gonias, Steven L.; Coppinger, Judith A.

2015-01-01

Senescence is a prominent solid tumor response to therapy in which cells avoid apoptosis and instead enter into prolonged cell cycle arrest. We applied a quantitative proteomics screen to identify signals that lead to therapy-induced senescence and discovered that Bcl2-associated athanogene 3 (Bag3) is up-regulated after adriamycin treatment in MCF7 cells. Bag3 is a member of the BAG family of co-chaperones that interacts with Hsp70. Bag3 also regulates major cell-signaling pathways. Mass spectrometry analysis of the Bag3 Complex revealed a novel interaction between Bag3 and Major Vault Protein (MVP). Silencing of Bag3 or MVP shifts the cellular response to adriamycin to favor apoptosis. We demonstrate that Bag3 and MVP contribute to apoptosis resistance in therapy-induced senescence by increasing the level of activation of extracellular signal-regulated kinase1/2 (ERK1/2). Silencing of either Bag3 or MVP decreased ERK1/2 activation and promoted apoptosis in adriamycin-treated cells. An increase in nuclear accumulation of MVP is observed during therapy-induced senescence and the shift in MVP subcellular localization is Bag3-dependent. We propose a model in which Bag3 binds to MVP and facilitates MVP accumulation in the nucleus, which sustains ERK1/2 activation. We confirmed that silencing of Bag3 or MVP shifts the response toward apoptosis and regulates ERK1/2 activation in a panel of diverse breast cancer cell lines. This study highlights Bag3-MVP as an important complex that regulates a potent prosurvival signaling pathway and contributes to chemotherapy resistance in breast cancer. PMID:24997994

Reducing single-use plastic shopping bags in the USA.

PubMed

Wagner, Travis P

2017-12-01

In the USA, local governments have the primary responsibility to manage MSW. However, local governments lack the authority to explicitly shift costs or responsibility back onto the producer for specific problem wastes. A particularly problematic waste for local governments is the single-use plastic bag. In 2014, in the USA, 103.465 billion single-use plastic shopping bags were consumed. Because of their extremely low recyclability rate, plastic bags remain a significant source of land-based litter and marine debris and impair stormwater management systems. They also reduce the effectiveness of automated recycling systems. In response, local governments increasingly have adopted a variety of measures specifically intended to reduce the store-level consumption of single-use shopping bags in 5 major categories: bans, imposition of fees and taxes, establishing minimum product design of bags, requiring consumer education, and mandating retailer take-back programs. As of September 2017, there were 271 local governments in the USA with plastic bag ordinances covering 9.7% of the nation's population. The majority (95%) of the ordinances is a ban on single-use plastic bags; 56.9% of these bans also include a mandatory fee on paper and/or reusable bags. For the fee-based ordinances, the mode is $0.10 per bag; every tax/fee ordinance allows retailers to retain some or all the collected fee. As local governments continue to increase their actions on plastic bags, 11 states have enacted laws to prohibit local governments from regulating single-use plastic bags. Because of the success with single-use bags, local governments are also enacting similar ordinances on single-use expanded polystyrene consumer products and other single-use plastic products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Vapor pressure measured with inflatable plastic bag

NASA Technical Reports Server (NTRS)

1965-01-01

Deflated plastic bag in a vacuum chamber measures initial low vapor pressures of materials. The bag captures the test sample vapors and visual observation of the vapor-inflated bag under increasing external pressures yields pertinent data.

An Isotope Study of Hydrogenation of poly-Si/SiOx Passivated Contacts for Si Solar Cells: Preprint

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

Schnabel, Manuel; Nemeth, William; van de Loo, Bas, W.H.

2017-06-26

For many years, the record Si solar cell efficiency stood at 25.0%. Only recently have several companies and institutes managed to produce more efficient cells, using passivated contacts of made doped poly-Si or a-Si:H and a passivating intrinsic interlayer in all cases. Common to these designs is the need to passivate the layer stack with hydrogen. In this contribution, we perform a systematic study of passivated contact passivation by hydrogen, using poly-Si/SiOx passivated contacts on n-Cz-Si, and ALD Al2O3 followed by a forming gas anneal (FGA) as the hydrogen source. We study p-type and n-type passivated contacts with implied Vocmore » exceeding 690 and 720 mV, respectively, and perform either the ALD step or the FGA with deuterium instead of hydrogen in order to separate the two processes via SIMS. By examining the deuterium concentration at the SiOx in both types of samples, we demonstrate that the FGA supplies negligible hydrogen species to the SiOx, regardless of whether the FGA is hydrogenated or deuterated. Instead, it supplies the thermal energy needed for hydrogen species in the Al2O3 to diffuse there. Furthermore, the concentration of hydrogen species at the SiOx can saturate while implied Voc continues to increase, showing that the energy from the FGA is also required for hydrogen species already at the SiOx to find recombination-active defects to passivate.« less

Method for fabricating silicon cells

DOEpatents

Ruby, Douglas S.; Basore, Paul A.; Schubert, W. Kent

1998-08-11

A process for making high-efficiency solar cells. This is accomplished by forming a diffusion junction and a passivating oxide layer in a single high-temperature process step. The invention includes the class of solar cells made using this process, including high-efficiency solar cells made using Czochralski-grown silicon.

PERFORMANCE OF A NEW PASSIVE DIFFUSION SAMPLER FOR SOIL GAS AND GROUND WATER SAMPLING

EPA Science Inventory

Conventional practice to estimate intrusion of fuel vapors from ground water to buildings measures the concentration of BTEX in ground water beneath the building using a conventional well screened across the water table. Conventional practice assumes that the concentration of co...

Protection against head injuries should not be optional: a case for mandatory installation of side-curtain air bags.

PubMed

Stuke, Lance E; Nirula, Raminder; Gentilello, Larry M; Shafi, Shahid

2010-10-01

More than 9,000 vehicle occupants die each year in side-impact vehicle collisions, primarily from head injuries. The authors hypothesized that side-curtain air bags significantly improve head and neck safety in side-impact crash testing. Side-impact crash-test data were obtained from the Insurance Institute for Highway Safety, which ranks occupant protection as good, acceptable, marginal, or poor. Vehicles of the same make and model that underwent side-impact crash testing both with and without side-curtain air bags were compared, as well as the protective effect of these air bags on occupants' risk for head and neck injury. Of all the passenger vehicles, 25 models have undergone side-impact crash testing with and without side-curtain air bags by the Insurance Institute for Highway Safety. Only 3 models without side-curtain air bags (12%) provided good head and neck protection for drivers, while 21 cars with side-curtain air bags (84%) provided good protection (P < .001). For rear passengers, the added protection from side-curtain air bags was less dramatic but significant (84% without vs 100% with side-curtain air bags, P = .04). Side-curtain air bags significantly improve vehicle occupant safety in side-impact crash tests. Installation of these air bags should be federally mandated in all passenger vehicles. Copyright © 2010 Elsevier Inc. All rights reserved.

Efficacy of side air bags in reducing driver deaths in driver-side collisions.

PubMed

Braver, Elisa R; Kyrychenko, Sergey Y

2004-03-15

Side air bags, a relatively new technology designed to protect the head and/or torso in side-impact collisions, are becoming increasingly common in automobiles. Their efficacy in preventing US driver deaths among cars struck on the near (driver's) side was examined using data from the Fatality Analysis Reporting System and the General Estimates System. Risk ratios for driver death per nearside collision during 1999-2001 were computed for head/torso and torso-only side air bags in cars from model years 1997-2002, relative to cars without side air bags. Confounding was addressed by adjusting nearside risk ratios for front- and rear-impact mortality, which is unaffected by side air bags. Risk ratios were 0.55 (95% confidence interval: 0.43, 0.71) for head/torso air bags and 0.89 (95% confidence interval: 0.79, 1.01) for torso-only air bags. Risk was reduced when cars with head/torso air bags were struck by cars/minivans (significant) or pickup trucks/sport utility vehicles (nonsignificant). Risk was reduced in two-vehicle collisions and among male drivers and drivers aged 16-64 years. Protective effects associated with torso-only air bags were observed in single-vehicle crashes and among male and 16- to 64-year-old drivers. Head/torso side air bags appear to be very effective in reducing nearside driver deaths, whereas torso-only air bags appear less protective.

A role of BAG3 in regulating SNCA/α-synuclein clearance via selective macroautophagy.

PubMed

Cao, Yu-Lan; Yang, Ya-Ping; Mao, Cheng-Jie; Zhang, Xiao-Qi; Wang, Chen-Tao; Yang, Jing; Lv, Dong-Jun; Wang, Fen; Hu, Li-Fang; Liu, Chun-Feng

2017-12-01

Many studies reveal that BAG3 plays a critical role in the regulation of protein degradation via macroautophagy. However, it remains unknown whether BAG3 affects the quality control of α-synuclein (SNCA), a Parkinson's disease-related protein. In this study, we demonstrated the increases of BAG3 expression in the ventral midbrain of SNCA A53T transgenic mice and also in MG132-treated PC12 cells overexpressing wild-type SNCA (SNCA WT -PC12). Moreover, we showed that BAG3 overexpression was sufficient to enhance the autophagy activity while knockdown of Bag3 reduced it in SNCA WT -PC12 cells. Immunoprecipitation revealed that BAG3 interacted with heat shock protein 70 and sequestosome 1. The immunostaining also showed the perinuclear accumulation and colocalization of BAG3 with these 2 proteins, as well as with LC3 dots in tyrosine hydroxylase-positive neurons in the midbrain of SNCA A53T mice. BAG3 overexpression was able to modulate SNCA degradation via macroautophagy which was prevented by Atg5 knockdown. Taken together, these results indicate that BAG3 plays a relevant role in regulating SNCA clearance via macroautophagy, and the heat shock protein 70-BAG3-sequestosome 1 complex may be involved in this process. Copyright © 2017 Elsevier Inc. All rights reserved.

BAG3 protects bovine papillomavirus type 1-transformed equine fibroblasts against pro-death signals.

PubMed

Cotugno, Roberta; Gallotta, Dario; d'Avenia, Morena; Corteggio, Annunziata; Altamura, Gennaro; Roperto, Franco; Belisario, Maria Antonietta; Borzacchiello, Giuseppe

2013-07-22

In human cancer cells, BAG3 protein is known to sustain cell survival. Here, for the first time, we demonstrate the expression of BAG3 protein both in equine sarcoids in vivo and in EqS04b cells, a sarcoid-derived fully transformed cell line harbouring bovine papilloma virus (BPV)-1 genome. Evidence of a possible involvement of BAG3 in equine sarcoid carcinogenesis was obtained by immunohistochemistry analysis of tumour samples. We found that most tumour samples stained positive for BAG3, even though to a different grade, while normal dermal fibroblasts from healthy horses displayed very weak staining pattern for BAG3 expression. By siRNA technology, we demonstrate in EqS04b the role of BAG3 in counteracting basal as well as chemical-triggered pro-death signals. BAG3 down-modulation was indeed shown to promote cell death and cell cycle arrest in G0/G1. In addition, we found that BAG3 silencing sensitized EqS04b cells to phenethylisothiocyanate (PEITC), a promising cancer chemopreventive/chemotherapeutic agent present in edible cruciferous vegetables. Notably, such a pro-survival role of BAG3 was less marked in E. Derm cells, an equine BPV-negative fibroblast cell line taken as a normal counterpart. Altogether our findings might suggest a mutual cooperation between BAG3 and viral oncoproteins to sustain cell survival.

BAG3 protects Bovine Papillomavirus type 1-transformed equine fibroblasts against pro-death signals

PubMed Central

2013-01-01

In human cancer cells, BAG3 protein is known to sustain cell survival. Here, for the first time, we demonstrate the expression of BAG3 protein both in equine sarcoids in vivo and in EqS04b cells, a sarcoid-derived fully transformed cell line harbouring bovine papilloma virus (BPV)-1 genome. Evidence of a possible involvement of BAG3 in equine sarcoid carcinogenesis was obtained by immunohistochemistry analysis of tumour samples. We found that most tumour samples stained positive for BAG3, even though to a different grade, while normal dermal fibroblasts from healthy horses displayed very weak staining pattern for BAG3 expression. By siRNA technology, we demonstrate in EqS04b the role of BAG3 in counteracting basal as well as chemical-triggered pro-death signals. BAG3 down-modulation was indeed shown to promote cell death and cell cycle arrest in G0/G1. In addition, we found that BAG3 silencing sensitized EqS04b cells to phenethylisothiocyanate (PEITC), a promising cancer chemopreventive/chemotherapeutic agent present in edible cruciferous vegetables. Notably, such a pro-survival role of BAG3 was less marked in E. Derm cells, an equine BPV-negative fibroblast cell line taken as a normal counterpart. Altogether our findings might suggest a mutual cooperation between BAG3 and viral oncoproteins to sustain cell survival. PMID:23876161

BAG3 sensitizes cancer cells exposed to DNA damaging agents via direct interaction with GRP78.

PubMed

Kong, De-Hui; Zhang, Qiang; Meng, Xin; Zong, Zhi-Hong; Li, Chao; Liu, Bao-Qin; Guan, Yifu; Wang, Hua-Qin

2013-12-01

Bcl-2 associated athanogene 3 (BAG3) has a modular structure that contains a BAG domain, a WW domain, a proline-rich (PxxP) domain to mediate potential interactions with chaperons and other proteins that participate in more than one signal transduction. In search for novel interacting partners, the current study identified that 78kDa glucose-regulated protein (GRP78) was a novel partner interacting with BAG3. Interaction between GRP78 and BAG3 was confirmed by coimmunoprecipitation and glutathione S-transferase (GST) pulldown. We also identified that the ATPase domain of GRP78 and BAG domain of BAG3 mediated their interaction. Counterintuitive for a prosurvival protein, BAG3 was found to promote the cytotoxicity of breast cancer MCF7, thyroid cancer FRO and glioma U87 cells subjected to genotoxic stress. In addition, the current study demonstrated that BAG3 interfered with the formation of the antiapoptotic GRP78-procaspase-7 complex, which resulted in an increased genotoxic stress-induced cytotoxicity in cancer cells. Furthermore, overexpression of GRP78 significantly blocked the enhancing effects of BAG3 on activation of caspase-7 and induction of apoptosis by genotoxic stress. Overall, these results suggested that through direct interaction BAG3 could prevent the antiapoptotic effect of GRP78 upon genotoxic stress. © 2013.

Non-Flammable Containment Bag and Enclosure Development for International Space Station Use

NASA Technical Reports Server (NTRS)

Inamdar, Sunil; Cadogan, Dave; Worthy, Erica

2014-01-01

Work conducted on the International Space Station (ISS) requires the use of a significant quantity of containment bags to hold specimens, equipment, waste, and other material. The bags are in many shapes and sizes, and are typically manufactured from polyethylene materials. The amount of bags being used on ISS has grown to the point where fire safety has become a concern because of the flammability of polyethylene. Recently, a new re-sealable bag design has been developed that is manufactured from a specialized non-flammable material called Armorflex 301 that was designed specifically for this application. Besides being non-flammable, Armorflex 301 is also FDA compliant, clear, flexible, and damage tolerant. The bags can be made with closure mechanisms that resemble ZipLoc® bags, or can be open top. Sample bags have been laboratory tested by NASA to verify materials properties, and evaluated by astronauts on the ISS in 2012. Flexloc bag manufacturing will commence in 2014 to support a transition away from polyethylene on ISS. In addition to re-sealable bags, other larger containment systems such as flexible gloveboxes, deployable clean rooms, and other devices manufactured from Armorflex 301 are being explored for use on ISS and in similar confined space locations where flammability is an issue. This paper will describe the development of the Armorflex 301 material, the Flexloc bag, and other containment systems being explored for use in confined areas

Design of Control System for Flexible Packaging Bags Palletizing Production Line Based on PLC

NASA Astrophysics Data System (ADS)

Zheng, Huiping; Chen, Lin; Zhao, Xiaoming; Liu, Zhanyang

Flexible packaging bags palletizing production line is to put the bags in the required area according to particular order and size, in order to finish handling, storage, loading and unloading, transportation and other logistics work of goods. Flexible packaging bags palletizing line is composed of turning bags mechanism, shaping mechanism, indexing mechanism, marshalling mechanism, pushing bags mechanism, pressing bags mechanism, laminating mechanism, elevator, tray warehouse, tray conveyor and loaded tray conveyor. Whether the whole production line can smoothly run depends on each of the above equipment and precision control among them. In this paper the technological process and the control logic of flexible packaging bags palletizing production line is introduced. Palletizing process of the production line realized automation by means of a control system based on programmable logic controller (PLC). It has the advantages of simple structure, reliable and easy maintenance etc.

Anisotropic diffusion in mesh-free numerical magnetohydrodynamics

NASA Astrophysics Data System (ADS)

Hopkins, Philip F.

2017-04-01

We extend recently developed mesh-free Lagrangian methods for numerical magnetohydrodynamics (MHD) to arbitrary anisotropic diffusion equations, including: passive scalar diffusion, Spitzer-Braginskii conduction and viscosity, cosmic ray diffusion/streaming, anisotropic radiation transport, non-ideal MHD (Ohmic resistivity, ambipolar diffusion, the Hall effect) and turbulent 'eddy diffusion'. We study these as implemented in the code GIZMO for both new meshless finite-volume Godunov schemes (MFM/MFV). We show that the MFM/MFV methods are accurate and stable even with noisy fields and irregular particle arrangements, and recover the correct behaviour even in arbitrarily anisotropic cases. They are competitive with state-of-the-art AMR/moving-mesh methods, and can correctly treat anisotropic diffusion-driven instabilities (e.g. the MTI and HBI, Hall MRI). We also develop a new scheme for stabilizing anisotropic tensor-valued fluxes with high-order gradient estimators and non-linear flux limiters, which is trivially generalized to AMR/moving-mesh codes. We also present applications of some of these improvements for SPH, in the form of a new integral-Godunov SPH formulation that adopts a moving-least squares gradient estimator and introduces a flux-limited Riemann problem between particles.

Study of drug diffusion rate by laser beam deflection technique

NASA Astrophysics Data System (ADS)

Swapna, Mohanachandran Nair. S.; Anitha, Madhu J.; Sankararaman, Sankaranarayana Iyer

2017-06-01

Drug administration is an unavoidable part of treatment. When a drug is administered orally or intravenously, it gets absorbed into the blood stream. The rate and efficiency of absorption depend on the route of administration. When a drug is administered through the oral route, it penetrates the epithelial cells of the intestinal mucosa. The diffusion of the drug into the blood stream depends on various parameters, such as concentration, temperature, and the nature of the mucous membrane. The passive diffusion of drugs is found to obey Fick's law. Water soluble drugs penetrate the cell membrane through aqueous channel or pores. Hence, the study of diffusion of drugs into the water and finally into the blood stream is important. An attempt has been made to study the diffusion of the drug in water as 60% to 80% of human body is water. For the study of drug diffusion in water, a commonly used cough syrup of specific gravity 1.263 is used. It is found that the diffusion rate increases with the concentration of the drug.

Commercial liquid bags as a potential source of venous air embolism in shoulder arthroscopy.

PubMed

Austin, Luke; Zmistowski, Benjamin; Tucker, Bradford; Hetrick, Robin; Curry, Patrick; Williams, Gerald

2010-09-01

Venous air embolism is a rare but potentially fatal complication of arthroscopy. Fatal venous air embolism has been reported with as little as 100 mL of air entering the venous system. During liquid-only arthroscopy, avenues for air introduction into the joint are limited. Therefore, we hypothesized that commercially prepared 3-L saline-solution bags are a source of potentially fatal amounts of gas that can be introduced into the joint by arthroscopic pumps. Eight 3-L arthroscopic saline-solution bags were obtained and visually inspected for air. The air was aspirated from four bags, and the volume of the air was recorded. A closed-system pump was prepared, and two 3-L bags were connected to it. The pump emptied into an inverted graduated cylinder immersed in a water bath. Both bags were allowed to run dry. Two more bags were then connected and also allowed to run dry. The air was quantified by the downward displacement of water. The experiment was then repeated with the four bags after the air had been aspirated from them. This experiment was performed at three institutions, with utilization of three pump systems and two brands of 3-L saline-solution bags. Air was visualized in all bags, and the bags contained between 34 and 85 mL of air. Arthroscopic pumps can pump air efficiently through the tubing. The total volumes of gas ejected from the tubing after the four 3-L bags had been emptied were 75, 80, and 235 mL. When bags from which the air had been evacuated were used, no air exited the system. Because a saline-solution arthroscopic pump is theoretically a closed system, venous air embolism has not been a concern. However, this study shows that it is possible to pump a fatal amount of air from 3-L saline-solution bags into an environment susceptible to the creation of emboli. Evacuation of air from the 3-L bags prior to use may eliminate this risk.

Simplification of the standard three-bag intravenous acetylcysteine regimen for paracetamol poisoning results in a lower incidence of adverse drug reactions.

PubMed

Wong, Anselm; Graudins, Andis

2016-01-01

Adverse reactions to intravenous (IV) acetylcysteine treatment in paracetamol overdose, are common. Previous studies suggest the incidence and severity of non-allergic anaphylactic reactions (NAARs) are influenced by the rate of acetylcysteine infusion. We compared the incidence of adverse drug events of a two-bag IV acetylcysteine regimen with that of the traditional three-bag regimen. This was a retrospective analysis of patients presenting with paracetamol overdose requiring treatment with acetylcysteine to three emergency departments. We prospectively identified all presentations where IV acetylcysteine was administered using a 20 h, two-bag regimen (200 mg/kg over 4 h followed by 100 mg/kg over 16 h) from February 2014 to June 2015. We compared this to an historical cohort treated with the 21 h three-bag IV regimen (150 mg/kg over 1 h, 50 mg/kg over 4 h and 100 mg/kg over 16 h) from October 2009 to October 2013. Medical and nursing notes were searched retrospectively for entries suggesting the presence of an adverse reaction. The primary outcome was incidence of NAARs and gastrointestinal reactions in each group. 389 presentations were treated with the three-bag regimen and 210 presentations received the two-bag regimen. NAARs were recorded more commonly with the three-bag acetylcysteine regimen than the two-bag regimen (10% vs 4.3%, p = 0.02, OR 2.5, 95% CI 1.1-5.8). There was no difference in reports of gastrointestinal reactions between cohorts (three-bag 39% vs two-bag 41%, p = 0.38, OR 1.17 95% CI (0.83-1.65)). The incidence of NAARs was significantly reduced by combining the first two bags of the traditional three-bag regimen and infusing these over 4 h at 50 mg/kg/hr. Simplifying the administration of acetylcysteine may have other benefits such as better utilisation of nursing time and reduced infusion administration errors. A two-bag 20 h acetylcysteine regimen was well tolerated and resulted in significantly fewer and milder NAARs than the standard three-bag regimen.

Physical and thermal properties of blood storage bags: implications for shipping frozen components on dry ice.

PubMed

Hmel, Peter J; Kennedy, Anthony; Quiles, John G; Gorogias, Martha; Seelbaugh, Joseph P; Morrissette, Craig R; Van Ness, Kenneth; Reid, T J

2002-07-01

Frozen blood components are shipped on dry ice. The lower temperature (-70 degrees C in contrast to usual storage at -30 degrees C) and shipping conditions may cause a rent in the storage bag, breaking sterility and rendering the unit useless. The rate of loss can reach 50 to 80 percent. To identify those bags with lower probability of breaking during shipment, the thermal and physical properties of blood storage bags were examined. Blood storage bags were obtained from several manufacturers and were of the following compositions: PVC with citrate, di-2-ethylhexylphthalate (DEHP), or tri-2-ethylhexyl-tri-mellitate (TEHTM) plasticizer; polyolefin (PO); poly(ethylene-co-vinyl acetate) (EVA); or fluorinated polyethylene propylene (FEP). The glass transition temperature (Tg) of each storage bag was determined. Bag thickness and measures of material strength (tensile modulus [MT] and time to achieve 0.5 percent strain [T0.5%]) were evaluated. M(T) and T0.5% measurements were made at 25 and -70 degrees C. Response to applied force at -70 degrees C was measured using an impact testing device and a drop test. The Tg of the bags fell into two groups: 70 to 105 degrees C (PO, FEP) and -50 to -17 degrees C (PVC with plasticizer, EVA). Bag thickness ranged from 0.14 to 0.41 mm. Compared to other materials, the ratios of M(T) and T0.5% for PVC bags were increased (p < or = 0.001) indicating that structural changes for PVC were more pronounced upon cooling from 25 to -70 degrees C. Bags containing EVA were more shock resistant, resulting in the lowest rate of breakage (10% breakage) when compared with PO (60% breakage, p = 0.0573) or PVC (100% breakage, p = 0.0001). Blood storage bags made of EVA appear better suited for shipping frozen blood components on dry ice and are cost-effective replacements for PVC bags. For the identification of blood storage bags meeting specific storage requirements, physical and thermal analyses of blood storage bags may be useful and remove empiricism from the process.

In-the-Bag Intraocular Lens Placement via Secondary Capsulorhexis with Radiofrequency Diathermy in Pediatric Aphakic Eyes

PubMed Central

Wang, Chunxiao; Zhang, Xinyu; Tang, Xiangchen; Liu, Jianping; Congdon, Nathan; Chen, Jingjing; Lin, Zhuoling; Liu, Yizhi

2013-01-01

Pediatric ophthalmologists increasingly recognize that the ideal site for intraocular lens (IOL) implantation is in the bag for aphakic eyes, but it is always very difficult via conventional technique. We conducted a prospective case series study to investigate the success rate and clinical outcomes of capsular bag reestablishment and in-the-bag IOL implantation via secondary capsulorhexis with radiofrequency diathermy (RFD) in pediatric aphakic eyes, in which twenty-two consecutive aphakic pediatric patients (43 aphakic eyes) enrolled in the Childhood Cataract Program of the Chinese Ministry of Health were included. The included children underwent either our novel technique for secondary IOL implantation (with RFD) or the conventional technique (with a bent needle or forceps), depending on the type of preoperative proliferative capsular bag present. In total, secondary capsulorhexis with RFD was successfully applied in 32 eyes (32/43, 74.4%, age 5.6±2.3 years), of which capsular bag reestablishment and in-the-bag IOL implantation were both achieved in 30 eyes (30/43, 70.0%), but in the remaining 2 eyes (2/32, 6.2%) the IOLs were implanted in the sulcus with a capsular bag that was too small. Secondary capsulorhexis with conventional technique was applied in the other 11 eyes (11/43, 25.6%, age 6.9±2.3 years), of which capsular bag reestablishment and in-the-bag IOL implantation were both achieved only in 3 eyes(3/43, 7.0%), and the IOLs were implanted in the sulcus in the remaining 8 eyes. A doughnut-like proliferative capsular bag with an extensive Soemmering ring (32/43, 74.4%) was the main success factor for secondary capsulorhexis with RFD, and a sufficient capsular bag size (33/43, 76.7%) was an additional factor in successful in-the-bag IOL implantation. In conclusion, RFD secondary capsulorhexis technique has 70% success rate in the capsular bag reestablishment and in-the-bag IOL implantation in pediatric aphakic eyes, particularly effective in cases with a doughnut-like, extensively proliferative Soemmering ring. PMID:23638058

Lipid globule size in total nutrient admixtures prepared in three-chamber plastic bags.

PubMed

Driscoll, David F; Thoma, Andrea; Franke, Rolf; Klütsch, Karsten; Nehne, Jörg; Bistrian, Bruce R

2009-04-01

The stability of injectable lipid emulsions in three-chamber plastic (3CP) bags, applying the globule-size limits established by United States Pharmacopeia ( USP ) chapter 729, was studied. A total of five premixed total nutrient admixture (TNA) products packaged in 3CP bags from two different lipid manufacturers containing either 20% soybean oil or a mixture of soybean oil and medium-chain-triglyceride oil as injectable lipid emulsions were tested. Two low-osmolarity 3CP bags and three high-osmolarity 3CP bags were studied. All products were tested with the addition of trace elements and multivitamins. All additive conditions (with and without electrolytes) were tested in triplicate at time 0 (immediately after mixing) and at 6, 24, 30, and 48 hours after mixing; the bags were stored at 24-26 degrees C. All additives were equally distributed in each bag for comparative testing, applying both globule sizing methods outlined in USP chapter 729. Of the bags tested, all bags from one manufacturer were coarse emulsions, showing signs of significant growth in the large-diameter tail when mixed as a TNA formulation and failing the limits set by method II of USP chapter 729 from the outset and throughout the study, while the bags from the other manufacturer were fine emulsions and met these limits. Of the bags that failed, significant instability was noted in one series containing additional electrolytes. Injectable lipid emulsions provided in 3CP bags that did not meet the globule-size limits of USP chapter 729 produced coarser TNA formulations than emulsions that met the USP limits.

Involvement of JNK and NF-κB pathways in lipopolysaccharide (LPS)-induced BAG3 expression in human monocytic cells.

PubMed

Wang, Hua-Qin; Meng, Xin; Liu, Bao-Qin; Li, Chao; Gao, Yan-Yan; Niu, Xiao-Fang; Li, Ning; Guan, Yifu; Du, Zhen-Xian

2012-01-01

Lipopolysaccharide (LPS) is an outer-membrane glycolipid component of Gram-negative bacteria known for its fervent ability to activate monocytic cells and for its potent proinflammatory capabilities. Bcl-2-associated athanogene 3 (BAG3) is a survival protein that has been shown to be stimulated during cell response to stressful conditions, such as exposure to high temperature, heavy metals, proteasome inhibition, and human immunodeficiency virus 1 (HIV-1) infection. In addition, BAG3 regulates replication of Varicella-Zoster Virus (VZV) and Herpes Simplex Virus (HSV) replication, suggesting that BAG3 could participate in the host response to infection. In the current study, we found that LPS increased the expression of BAG3 in a dose- and time-dependent manner. Actinomycin D completely blocked the LPS-induced BAG3 accumulation, as well as LPS activated the proximal promoter of BAG3 gene, supported that the induction by LPS occurred at the level of gene transcription. LPS-induced BAG3 expression was blocked by JNK or NF-κB inhibition, suggesting that JNK and NF-κB pathways participated in BAG3 induction by LPS. In addition, we also found that induction of BAG3 was implicated in monocytic cell adhesion to extracellular matrix induced by LPS. Overall, the data support that BAG3 is induced by LPS via JNK and NF-κB-dependent signals, and involved in monocytic cell-extracellular matrix interaction, suggesting that BAG3 may have a role in the host response to LPS stimulation. Copyright © 2011 Elsevier Inc. All rights reserved.

Comparison of storage stability of odorous VOCs in polyester aluminum and polyvinyl fluoride Tedlar® bags.

PubMed

Kim, Yong-Hyun; Kim, Ki-Hyun; Jo, Sang-Hee; Jeon, Eui-Chan; Sohn, Jong Ryeul; Parker, David B

2012-01-27

Whole air sampling using containers such as flexible bags or rigid canisters is commonly used to collect samples of volatile organic compounds (VOC) in air. The objective of this study was to compare the stability of polyester aluminum (PEA) and polyvinyl fluoride (PVF, brand name Tedlar(®)) bags for gaseous VOC sampling. Eight VOC standards (benzene, toluene, p-xylene, styrene, methyl ethyl ketone, methyl isobutyl ketone, butyl acetate, and isobutyl alcohol) were placed into each bag at storage times of 0, 2, and 3 days prior to analyses by gas chromatography/mass spectrometry (GC/MS). From each bag representing each storage day, samples of 3 different mass loadings were withdrawn and analyzed to derive response factors (RF) of each chemical between the slope of the GC response (y-axis) vs. loaded mass (x-axis). The relative recoveries (RR) of VOC, if derived by dividing RF value of a given storage day by that of 0 day, varied by time, bag type, and VOC type. If the RR values after three days are compared, those of methyl isobutyl ketone were the highest with 96 (PVF) and 99% (PEA); however, the results of isobutyl alcohol were highly contrasting between the two bags with 31 and 94%, respectively. Differences in RR values between the two bag types increased with storage time, such that RR of PEA bags (88±10%) were superior to those of PVF bags (73±22%) after three days, demonstrating that VOC in PEA bags were more stable than in PVF bags. Copyright © 2011 Elsevier B.V. All rights reserved.

50 CFR 622.456 - Bag limits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... of Puerto Rico and the U.S. Virgin Islands § 622.456 Bag limits. (a) Applicability. Section 622.11(a... fishing license issued by Puerto Rico or the U.S. Virgin Islands. (b) Bag limit. The bag limit for spiny...

Enamel Surface with Pit and Fissure Sealant Containing 45S5 Bioactive Glass.

PubMed

Yang, S-Y; Kwon, J-S; Kim, K-N; Kim, K-M

2016-05-01

Enamel demineralization adjacent to pit and fissure sealants leads to the formation of marginal caries, which can necessitate the replacement of existing sealants. Dental materials with bioactive glass, which releases ions that inhibit dental caries, have been studied. The purpose of this study was to evaluate the enamel surface adjacent to sealants containing 45S5 bioactive glass (BAG) under simulated microleakage between the material and the tooth in a cariogenic environment. Sealants containing 45S5BAG filler were prepared as follows: 0% 45S5BAG + 50.0% glass (BAG0 group), 12.5% 45S5BAG + 37.5% glass (BAG12.5 group), 25.0% 45S5BAG + 25.0% glass (BAG25.0 group), 37.5% 45S5BAG + 12.5% glass (BAG37.5 group), and 50.0% 45S5BAG + 0% glass (BAG50.0 group). A cured sealant disk was placed over a flat bovine enamel disk, separated by a 60-µm gap, and immersed in lactic acid solution (pH 4.0) at 37 °C for 15, 30, and 45 d. After the storage period, each enamel disk was separated from the cured sealant disk, and the enamel surface was examined with optical 3-dimensional surface profilometer, microhardness tester, and scanning electron microscopy. The results showed a significant increase in roughness and a decrease in microhardness of the enamel surface as the proportion of 45S5BAG decreased (P< 0.05). In the scanning electron microscopy images, enamel surfaces with BAG50.0 showed a smooth surface, similar to those in the control group with distilled water, even after prolonged acid storage. Additionally, an etched pattern was observed on the surface of the demineralized enamel with a decreasing proportion of 45S5BAG. Increasing the 45S5BAG filler contents of the sealants had a significant impact in preventing the demineralization of the enamel surface within microgaps between the material and the tooth when exposed to a cariogenic environment. Therefore, despite some marginal leakage, these novel sealants may be effective preventive dental materials for inhibiting secondary caries at the margins. © International & American Associations for Dental Research 2016.

Triple bag hermetic technology for controlling a bruchid (Spermophagus sp.) (Coleoptera, Chrysomelidae) in stored Hibiscus sabdariffa grain.

PubMed

Amadou, L; Baoua, I B; Baributsa, D; Williams, S B; Murdock, L L

2016-10-01

We assessed the performance of hermetic triple layer Purdue Improved Crop Storage (PICS) bags for protecting Hibiscus sabdariffa grain against storage insects. The major storage pest in the grain was a bruchid, Spermophagus sp.. When we stored infested H. sabdariffa grain for six months in the woven polypropylene bags typically used by farmers, the Spermophagus population increased 33-fold over that initially present. The mean number of emergence holes per 100 seeds increased from 3.3 holes to 35.4 holes during this time period, while grain held for the same length of time in PICS bags experienced no increase in the numbers of holes. Grain weight loss in the woven control bags was 8.6% while no weight loss was observed in the PICS bags. Seed germination rates of grain held in woven bags for six months dropped significantly while germination of grain held in PICS bags did not change from the initial value. PICS bags can be used to safely store Hibiscus grain after harvest to protect against a major insect pest.

Cordyceps sinensis attenuates renal fibrosis and suppresses BAG3 induction in obstructed rat kidney.

PubMed

Du, Feng; Li, Si; Wang, Tian; Zhang, Hai-Yan; Zong, Zhi-Hong; Du, Zhen-Xian; Li, De-Tian; Wang, Hua-Qin; Liu, Bo; Miao, Jia-Ning; Bian, Xiao-Hui

2015-01-01

BAG3 regulates a number of cellular processes, including cell proliferation, apoptosis, adhesion and migration, and epithelial-mesenchymal transition (EMT). However, the role of BAG3 in renal tubular EMT and renal interstitial fibrosis remains elusive. This study aimed to examine the dynamic expression of BAG3 during renal fibrosis, and to investigate the efficacy of Cordyceps sinensis (C. sinensis) on renal fibrosis. A rat model of unilateral ureteral obstruction (UUO) was established, and the expression of BAG3 and α-SMA, and the efficacy of C. sinensis on renal fibrosis induced by UUO were examined. The results showed that UUO led to collagen accumulation, which was significantly suppressed by C. sinensis. UUO increased the expression of BAG3 and α-SMA, a mesenchymal marker, while UUO induced BAG3 and α-SMA expression was significantly inhibited by C. sinensis. In addition, immunohistochemical staining demonstrated that BAG3 immunoreactivity was restricted to tubular epithelium. In conclusion, BAG3 is a potential target for the prevention and/or treatment of renal fibrosis, and C. Sinensis is a promising agent for renal fibrosis.

Mixing of a passive scalar in isotropic and sheared homogeneous turbulence

NASA Technical Reports Server (NTRS)

Shirani, E.; Ferziger, J. H.; Reynolds, W. C.

1981-01-01

In order to calculate the velocity and scalar fields, the three dimensional, time-dependent equations of motion and the diffusion equation were solved numerically. The following cases were treated: isotropic, homogeneous turbulence with decay of a passive scalar; and homogeneous turbulent shear flow with a passive scalar whose mean varies linearly in the spanwise direction. The solutions were obtained at relatively low Reynolds numbers so that all of the turbulent scales could be resolved without modeling. Turbulent statistics such as integral length scales, Taylor microscales, Kolmogorov length scale, one- and two-point correlations of velocity-velocity and velocity-scalar, turbulent Prandtl/Schmidt number, r.m.s. values of velocities, the scalar quantity and pressure, skewness, decay rates, and decay exponents were calculated. The results are compared with the available expermental results, and good agreement is obtained.

Lunar regolith bagging system

NASA Technical Reports Server (NTRS)

Cannon, Reuben; Henninger, Scott; Levandoski, Mark; Perkins, Jim; Pitchon, Jack; Swats, Robin; Wessels, Roger

1990-01-01

A design of a lunar regolith bag and bagging system is described. The bags of regolith are to be used for construction applications on the lunar surface. The machine is designed to be used in conjunction with the lunar SKITTER currently under development. The bags for this system are 1 cu ft volume and are made from a fiberglass composite weave. The machinery is constructed mostly from a boron/aluminum composite. The machine can fill 120 bags per hour and work for 8 hours a day. The man hours to machine hours ratio to operate the machine is .5/8.

A BAG3 chaperone complex maintains cardiomyocyte function during proteotoxic stress

PubMed Central

Judge, Luke M.; Perez-Bermejo, Juan A.; Truong, Annie; Ribeiro, Alexandre J.S.; Yoo, Jennie C.; Jensen, Christina L.; Mandegar, Mohammad A.; Huebsch, Nathaniel; Kaake, Robyn M.; So, Po-Lin; Srivastava, Deepak; Krogan, Nevan J.

2017-01-01

Molecular chaperones regulate quality control in the human proteome, pathways that have been implicated in many diseases, including heart failure. Mutations in the BAG3 gene, which encodes a co-chaperone protein, have been associated with heart failure due to both inherited and sporadic dilated cardiomyopathy. Familial BAG3 mutations are autosomal dominant and frequently cause truncation of the coding sequence, suggesting a heterozygous loss-of-function mechanism. However, heterozygous knockout of the murine BAG3 gene did not cause a detectable phenotype. To model BAG3 cardiomyopathy in a human system, we generated an isogenic series of human induced pluripotent stem cells (iPSCs) with loss-of-function mutations in BAG3. Heterozygous BAG3 mutations reduced protein expression, disrupted myofibril structure, and compromised contractile function in iPSC-derived cardiomyocytes (iPS-CMs). BAG3-deficient iPS-CMs were particularly sensitive to further myofibril disruption and contractile dysfunction upon exposure to proteasome inhibitors known to cause cardiotoxicity. We performed affinity tagging of the endogenous BAG3 protein and mass spectrometry proteomics to further define the cardioprotective chaperone complex that BAG3 coordinates in the human heart. Our results establish a model for evaluating protein quality control pathways in human cardiomyocytes and their potential as therapeutic targets and susceptibility factors for cardiac drug toxicity. PMID:28724793

Evidence for the Role of BAG3 in Mitochondrial Quality Control in Cardiomyocytes

PubMed Central

Tahrir, Farzaneh G.; Knezevic, Tijana; Gupta, Manish K.; Gordon, Jennifer; Cheung, Joseph Y.; Feldman, Arthur M.; Khalili, Kamel

2017-01-01

Mitochondrial abnormalities impact the development of myofibrillar myopathies. Therefore, understanding the mechanisms underlying the removal of dysfunctional mitochondria from cells is of great importance toward understanding the molecular events involved in the genesis of cardiomyopathy. Earlier studies have ascribed a role for BAG3 in the development of cardiomyopathy in experimental animals leading to the identification of BAG3 mutations in patients with heart failure which may play a part in the onset of disease development and progression. BAG3 is co-chaperone of heat shock protein 70 (HSP70), which has been shown to modulate apoptosis and autophagy, in several cell models. In this study, we explore the potential role of BAG3 in mitochondrial quality control. We demonstrate that siRNA mediated suppression of BAG3 production in neonatal rat ventricular cardiomyocytes (NRVCs) significantly elevates the level of Parkin, a key component of mitophagy. We found that both BAG3 and Parkin are recruited to depolarized mitochondria and promote mitophagy. Suppression of BAG3 in NRVCs significantly reduces autophagy flux and eliminates expression of Tom20, an essential import receptor for mitochondria proteins, after induction of mitophagy. These observations suggest that BAG3 is critical for the maintenance of mitochondrial homeostasis under stress conditions, and disruptions in BAG3 expression impact cardiomyocyte function. PMID:27381181

A BAG3 chaperone complex maintains cardiomyocyte function during proteotoxic stress.

PubMed

Judge, Luke M; Perez-Bermejo, Juan A; Truong, Annie; Ribeiro, Alexandre Js; Yoo, Jennie C; Jensen, Christina L; Mandegar, Mohammad A; Huebsch, Nathaniel; Kaake, Robyn M; So, Po-Lin; Srivastava, Deepak; Pruitt, Beth L; Krogan, Nevan J; Conklin, Bruce R

2017-07-20

Molecular chaperones regulate quality control in the human proteome, pathways that have been implicated in many diseases, including heart failure. Mutations in the BAG3 gene, which encodes a co-chaperone protein, have been associated with heart failure due to both inherited and sporadic dilated cardiomyopathy. Familial BAG3 mutations are autosomal dominant and frequently cause truncation of the coding sequence, suggesting a heterozygous loss-of-function mechanism. However, heterozygous knockout of the murine BAG3 gene did not cause a detectable phenotype. To model BAG3 cardiomyopathy in a human system, we generated an isogenic series of human induced pluripotent stem cells (iPSCs) with loss-of-function mutations in BAG3. Heterozygous BAG3 mutations reduced protein expression, disrupted myofibril structure, and compromised contractile function in iPSC-derived cardiomyocytes (iPS-CMs). BAG3-deficient iPS-CMs were particularly sensitive to further myofibril disruption and contractile dysfunction upon exposure to proteasome inhibitors known to cause cardiotoxicity. We performed affinity tagging of the endogenous BAG3 protein and mass spectrometry proteomics to further define the cardioprotective chaperone complex that BAG3 coordinates in the human heart. Our results establish a model for evaluating protein quality control pathways in human cardiomyocytes and their potential as therapeutic targets and susceptibility factors for cardiac drug toxicity.

Two cases of death due to plastic bag suffocation.

PubMed

Nadesan, K; Beng, O B

2001-01-01

Deaths due to plastic bag suffocation or plastic bag asphyxia are not reported in Malaysia. In the West many suicides by plastic bag asphyxia, particularly in the elderly and those who are chronically and terminally ill, have been reported. Accidental deaths too are not uncommon in the West, both among small children who play with shopping bags and adolescents who are solvent abusers. Another well-known but not so common form of accidental death from plastic bag asphyxia is sexual asphyxia, which is mostly seen among adult males. Homicide by plastic bag asphyxia too is reported in the West and the victims are invariably infants or adults who are frail or terminally ill and who cannot struggle. Two deaths due to plastic bag asphyxia are presented. Both the autopsies were performed at the University Hospital Mortuary, Kuala Lumpur. Both victims were 50-year old married Chinese males. One death was diagnosed as suicide and the other as sexual asphyxia. Sexual asphyxia is generally believed to be a problem associated exclusively with the West. Specific autopsy findings are often absent in deaths due to plastic bag asphyxia and therefore such deaths could be missed when some interested parties have altered the scene and most importantly have removed the plastic bag. A visit to the scene of death is invariably useful.

[Impact of storage conditions and time on herb of Lonicera macranthoides].

PubMed

Ma, Peng; Li, Long-Yun; Zhang, Ying

2014-03-01

To study the effect of different storage conditions and storage time on herb quality of Lonicera macranthoides, different packaging materials including vacuum plastic bags, plastic bags, woven bags, sealed with endometrial bags, paper bags, sack bags were selected for the study under different storage conditions including room temperature, 5 degrees C refrigerator, low temperature of - 20 degrees C refrigerator and desiccator. Twenty-four batches of samples were used for the study, and active ingredients were determined. The experimental results showed that the ingredients in each storage group changed with the storage time, storage conditions (storage environment, packaging). Under the same storage time, the storage environment (temperature, humidity) had effect on the stability of herb quality. Low temperature had less effect on herb quality. The effect of packaging on herb quality was as following: plastic vacuum packaging > woven with endometrial sealed packaging > plastic bag > woven bag > sack bags > paper bags. Under the same storage conditions, with the increase of storage time, caffeic acid content increased slowly, and other five ingredients content decreased gradually. Storage time affected significantly on the intrinsic quality (chemical composition) and appearance of herb. It is suggested that low temperature (5 degrees C), dark and sealed storage are suitable for storage of L. macranthoides herb, the storage time should be not more than 24 months.

Efflux of drugs and solutes from brain: the interactive roles of diffusional transcapillary transport, bulk flow and capillary transporters.

PubMed

Groothuis, Dennis R; Vavra, Michael W; Schlageter, Kurt E; Kang, Eric W-Y; Itskovich, Andrea C; Hertzler, Shannon; Allen, Cathleen V; Lipton, Howard L

2007-01-01

We examined the roles of diffusion, convection and capillary transporters in solute removal from extracellular space (ECS) of the brain. Radiolabeled solutes (eight with passive distribution and four with capillary or cell transporters) were injected into the brains of rats (n=497) and multiple-time point experiments measured the amount remaining in brain as a function of time. For passively distributed compounds, there was a relationship between lipid:water solubility and total brain efflux:diffusional efflux, which dominated when k(p), the transcapillary efflux rate constant, was >10(0) h(-1); when 10(-1)

Improvement of Electrical Characteristics and Stability of Amorphous Indium Gallium Zinc Oxide Thin Film Transistors Using Nitrocellulose Passivation Layer.

PubMed

Shin, Kwan Yup; Tak, Young Jun; Kim, Won-Gi; Hong, Seonghwan; Kim, Hyun Jae

2017-04-19

In this research, nitrocellulose is proposed as a new material for the passivation layers of amorphous indium gallium zinc oxide thin film transistors (a-IGZO TFTs). The a-IGZO TFTs with nitrocellulose passivation layers (NC-PVLs) demonstrate improved electrical characteristics and stability. The a-IGZO TFTs with NC-PVLs exhibit improvements in field-effect mobility (μ FE ) from 11.72 ± 1.14 to 20.68 ± 1.94 cm 2 /(V s), threshold voltage (V th ) from 1.85 ± 1.19 to 0.56 ± 0.35 V, and on/off current ratio (I on/off ) from (5.31 ± 2.19) × 10 7 to (4.79 ± 1.54) × 10 8 compared to a-IGZO TFTs without PVLs, respectively. The V th shifts of a-IGZO TFTs without PVLs, with poly(methyl methacrylate) (PMMA) PVLs, and with NC-PVLs under positive bias stress (PBS) test for 10,000 s represented 5.08, 3.94, and 2.35 V, respectively. These improvements were induced by nitrogen diffusion from NC-PVLs to a-IGZO TFTs. The lone-pair electrons of diffused nitrogen attract weakly bonded oxygen serving as defect sites in a-IGZO TFTs. Consequently, the electrical characteristics are improved by an increase of carrier concentration in a-IGZO TFTs, and a decrease of defects in the back channel layer. Also, NC-PVLs have an excellent property as a barrier against ambient gases. Therefore, the NC-PVL is a promising passivation layer for next-generation display devices that simultaneously can improve electrical characteristics and stability against ambient gases.

Method for fabricating silicon cells

DOEpatents

Ruby, D.S.; Basore, P.A.; Schubert, W.K.

1998-08-11

A process is described for making high-efficiency solar cells. This is accomplished by forming a diffusion junction and a passivating oxide layer in a single high-temperature process step. The invention includes the class of solar cells made using this process, including high-efficiency solar cells made using Czochralski-grown silicon. 9 figs.

Evaluation of a New Passive Diffusion Sampler for Improving the Calibration of Models to Evaluate Vapor Movement at UST Sites

EPA Science Inventory

Understanding transport of volatile contaminants in soil gas and ground water, particularly those associated with underground storage tanks (USTs), requires a detailed knowledge about the depth-dependent distribution of chemical species in the subsurface. A risk assessment of th...

A New Passive Diffusion Sampler for Improving the Calibration of Models to Evaluate Vapor Movement at UST Sites

EPA Science Inventory

Understanding transport of volatile contaminants in soil gas and ground water, particularly those associated with underground storage tanks (USTs), requires a detailed knowledge about the depthdependent distribution of chemical species in the subsurface. A risk assessment of the...

PERFORMANCE OF A NEW PASSIVE DIFFUSION SAMPLER FOR MONITORING BENZENE IN EITHER SOIL GAS OR GROUND WATER

EPA Science Inventory

Understanding transport of volatile contaminants in soil gas and ground water, particularly those associated with underground storage tanks, requires a detailed knowledge about the depth-dependent distribution of chemical species in the subsurface. A risk assessment of the moveme...

Association of first- and second-generation air bags with front occupant death in car crashes: a matched cohort study.

PubMed

Olson, Carin M; Cummings, Peter; Rivara, Frederick P

2006-07-15

First-generation air bags entail a decreased risk of death for most front seat occupants in car crashes but an increased risk for children. Second-generation air bags were developed to reduce the risks for children, despite the possibility of decreasing protection for others. Using a matched cohort design, the authors estimated risk ratios for death for use of each generation of air bag versus no air bag, adjusted for seat position, restraint use, sex, age, and all vehicle and crash characteristics, among 128,208 automobile occupants involved in fatal crashes on US roadways during 1990-2002. The authors then compared adjusted risk ratios (aRRs) between the two generations of air bags. Among front seat occupants, the aRR for death with a first-generation air bag was 0.90 (95% confidence interval (CI): 0.86, 0.94); the aRR with a second-generation air bag was 0.89 (95% CI: 0.79, 1.00) (p = 0.83 for comparison of aRRs). Among children under age 6 years, the aRR with a first-generation air bag was 1.66 (95% CI: 1.20, 2.30), while the aRR with a second-generation air bag was 1.10 (95% CI: 0.63, 1.93) (p = 0.20 for comparison of aRRs). The differences in aRRs between first- and second-generation air bags among other subgroups were small and not statistically significant.

The field performance of frontal air bags: a review of the literature.

PubMed

Kent, Richard; Viano, David C; Crandall, Jeff

2005-03-01

This article presents a broad review of the literature on frontal air bag field performance, starting with the initial government and industry projections of effectiveness and concluding with the most recent assessments of depowered systems. This review includes as many relevant metrics as practicable, interprets the findings, and provides references so the interested reader can further evaluate the limitations, confounders, and utility of each metric. The evaluations presented here range from the very specific (individual case studies) to the general (statistical analyses of large databases). The metrics used to evaluate air bag performance include fatality reduction or increase; serious, moderate, and minor injury reduction or increase; harm reduction or increase; and cost analyses, including insurance costs and the cost of life years saved for various air bag systems and design philosophies. The review begins with the benefits of air bags. Fatality and injury reductions attributable to the air bag are presented. Next, the negative consequences of air bag deployment are described. Injuries to adults and children and the current trends in air bag injury rates are discussed, as are the few documented instances of inadvertent deployments or non-deployment in severe crashes. In the third section, an attempt is made to quantify the influence of the many confounding factors that affect air bag performance. The negative and positive characteristics of air bags are then put into perspective within the context of societal costs and benefits. Finally, some special topics, including risk homeostasis and the performance of face bags, are discussed.

Using head-on collisions to compare risk of driver death by frontal air bag generation: a matched-pair cohort study.

PubMed

Braver, Elisa R; Kufera, Joseph A; Alexander, Melvin T; Scerbo, Marge; Volpini, Karen; Lloyd, Joseph P

2008-03-01

US air bag regulations were changed in 1997 to allow tests of unbelted male dummies in vehicles mounted and accelerated on sleds, resulting in longer crash pulses than rigid-barrier crashes. This change facilitated depowering of frontal air bags and was intended to reduce air bag-induced deaths. Controversy ensued as to whether sled-certified air bags could increase adult fatality risk. A matched-pair cohort study of two-vehicle, head-on, fatal collisions between drivers involving first-generation versus sled-certified air bags during 1998-2005 was conducted by using Fatality Analysis Reporting System data. Sled certification was ascertained from public information and a survey of automakers. Conditional Poisson regression for matched-pair cohorts was used to estimate risk ratios adjusted for age, seat belt status, vehicle type, passenger car size, and model year for driver deaths in vehicles with sled-certified air bags versus first-generation air bags. For all passenger-vehicle pairs, the adjusted risk ratio was 0.87 (95% confidence interval: 0.77, 0.98). In head-on collisions involving only passenger cars, the adjusted risk ratio was 1.04 (95% confidence interval: 0.85, 1.29). Increased fatality risk for drivers with sled-certified air bags was not observed. A borderline significant interaction between vehicle type and air bag generation suggested that sled-certified air bags may have reduced the risk of dying in head-on collisions among drivers of pickup trucks.

Automobile air bags: friend or foe? A case of air bag-associated ocular trauma and a related literature review.

PubMed

Kenney, Kristin S; Fanciullo, Lisa M

2005-07-01

Although air bags are placed in automobiles to act as safety devices, they have been shown to carry a risk of injury themselves. Ocular injury, in particular, can often be a direct consequence of air bag deployment. A case of ocular air bag injury is presented. A discussion and review of the current literature on this issue follows. A 63-year-old man was transferred to our clinic after sustaining injuries related to a motor vehicle accident, during which the automobile's air bag was deployed. Initial examination revealed many signs of blunt ocular trauma of the O.D., including iridodialysis, dislocated lens with traumatic cataract, and traumatic/inflammatory glaucoma. Initial B-scan showed an attached retina O.D. One month later, the patient underwent an attempted pars plana vitrectomy with lensectomy, iris repair, and insertion of an anterior chamber intraocular lens. Complications arose during the procedure, and a total retinal detachment developed. Resultant acuity is no light perception O.D. Although ocular morbidity can be a direct consequence of air bag deployment, most eye injuries are minimal, and seem to be outweighed by the benefits of air bags. Drivers, as well as passengers, can minimize associated injuries by adhering to specific safety guidelines. This, as well as continual modification and improvement in air bag design, will maximize the safety of air bags and decrease the incidence of vision-threatening ocular injury caused by air bag deployment.

PKCδ-mediated phosphorylation of BAG3 at Ser187 site induces epithelial-mesenchymal transition and enhances invasiveness in thyroid cancer FRO cells.

PubMed

Li, N; Du, Z-X; Zong, Z-H; Liu, B-Q; Li, C; Zhang, Q; Wang, H-Q

2013-09-19

Protein kinase C delta (PKCδ) is a serine (Ser)/threonine kinase, which regulates numerous cellular processes, including proliferation, differentiation, migration and apoptosis. In the current study, Chinese hamster ovary cells were transfected with either a constitutively activated PKCδ or a dominant negative PKCδ, phosphoprotein enrichment, two-dimensional difference gel electrophoresis and mass spectrometry was combined to globally identified candidates of PKCδ cascade. We found that Bcl-2 associated athanogene 3 (BAG3) was one of the targets of PKCδ cascade, and BAG3 interacted with PKCδ in vivo. In addition, we clarified that BAG3 was phosphorylate at Ser187 site in a PKCδ-dependent manner in vivo. BAG3 has been implicated in multiple cellular functions, including proliferation, differentiation, apoptosis, migration, invasion, macroautophagy and so on. We generated wild-type (WT)-, Ser187Ala (S187A)- or Ser187Asp (S187D)-BAG3 stably expressing FRO cells, and noticed that phosphorylation state of BAG3 influenced FRO morphology. Finally, for the first time, we showed that BAG3 was implicated in epithelial-mesenchymal transition (EMT) procedure, and phosphorylation state at Ser187 site had a critical role in EMT regulation by BAG3. Collectively, the current study indicates that BAG3 is a novel substrate of PKCδ, and PKCδ-mediated phosphorylation of BAG3 is implicated in EMT and invasiveness of thyroid cancer cells.

An interaction study in mammalian cells demonstrates weak binding of HSPB2 to BAG3, which is regulated by HSPB3 and abrogated by HSPB8.

PubMed

Morelli, Federica F; Mediani, Laura; Heldens, Lonneke; Bertacchini, Jessika; Bigi, Ilaria; Carrà, Arianna Dorotea; Vinet, Jonathan; Carra, Serena

2017-07-01

The ten mammalian small heat shock proteins (sHSPs/HSPBs) show a different expression profile, although the majority of them are abundant in skeletal and cardiac muscles. HSPBs form hetero-oligomers and homo-oligomers by interacting together and complexes containing, e.g., HSPB2/HSPB3 or HSPB1/HSPB5 have been documented in mammalian cells and muscles. Moreover, HSPB8 associates with the Hsc70/Hsp70 co-chaperone BAG3, in mammalian, skeletal, and cardiac muscle cells. Interaction of HSPB8 with BAG3 regulates its stability and function. Weak association of HSPB5 and HSPB6 with BAG3 has been also reported upon overexpression in cells, supporting the idea that BAG3 might indirectly modulate the function of several HSPBs. However, it is yet unknown whether other HSPBs highly expressed in muscles such as HSPB2 and HSPB3 also bind to BAG3. Here, we report that in mammalian cells, upon overexpression, HSPB2 binds to BAG3 with an affinity weaker than HSPB8. HSPB2 competes with HSPB8 for binding to BAG3. In contrast, HSPB3 negatively regulates HSPB2 association with BAG3. In human myoblasts that express HSPB2, HSPB3, HSPB8, and BAG3, the latter interacts selectively with HSPB8. Combining these data, it supports the interpretation that HSPB8-BAG3 is the preferred interaction.

The prosurvival protein BAG3: a new participant in vascular homeostasis.

PubMed

Carrizzo, Albino; Damato, Antonio; Ambrosio, Mariateresa; Falco, Antonia; Rosati, Alessandra; Capunzo, Mario; Madonna, Michele; Turco, Maria C; Januzzi, James L; De Laurenzi, Vincenzo; Vecchione, Carmine

2016-10-20

Bcl2-associated athanogene 3 (BAG3), is constitutively expressed in a few normal cell types, including myocytes, peripheral nerves and in the brain, and is also expressed in certain tumors. To date, the main studies about the role of BAG3 are focused on its pro-survival effect in tumors through various mechanisms that vary according to cellular type. Recently, elevated concentrations of a soluble form of BAG3 were described in patients affected by advanced stage of heart failure (HF), identifying BAG3 as a potentially useful biomarker in monitoring HF progression. Despite the finding of high levels of BAG3 in the sera of HF patients, there are no data on its possible role on the modulation of vascular tone and blood pressure levels. The aim of this study was to investigate the possible hemodynamic effects of BAG3 performing both in vitro and in vivo experiments. Through vascular reactivity studies, we demonstrate that BAG3 is capable of evoking dose-dependent vasorelaxation. Of note, BAG3 exerts its vasorelaxant effect on resistance vessels, typically involved in the blood pressure regulation. Our data further show that the molecular mechanism through which BAG3 exerts this effect is the activation of the PI3K/Akt signalling pathway leading to nitric oxide release by endothelial cells. Finally, we show that in vivo BAG3 administration is capable of regulating blood pressure and that this is dependent on eNOS regulation since this ability is lost in eNOS KO animals.

77 FR 17394 - Hazardous Materials: Approval and Communication Requirements for the Safe Transportation of Air...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-26

... Communication Requirements for the Safe Transportation of Air Bag Inflators, Air Bag Modules, and Seat-Belt... Regulations applicable to air bag inflators, air bag modules, and seat-belt pretensioners. The proposed... classified as a [[Page 17395

Bag molding processes

NASA Astrophysics Data System (ADS)

Slobodzinsky, A.

Features, materials, and techniques of vacuum, pressure, and autoclave FRP bag molding processes are described. The bags are used in sealed environments, inflated to flexibly force a curing FRP laminate to conform to a stiff mold form which defines the shape of the finished product. Densification is achieved as the bag presses out the voids and excess resin from the laminate, and consolidation occurs as the plies and adherends are bonded by the bag pressure. Curing techniques nominally involved room temperature or high temperature, and investigations of alternative techniques, such as induction, dielectric, microwave, xenon flash, UV, electron beam, and gamma radiation heating are proceeding. Polysulfone is the most common thermoplastic. Details are given of mold preparations, peel plies or release films and fabrics, bagging techniques, and reusable venting blankets and silicone rubber bags.

Advanced Air Bag Technology Assessment

NASA Technical Reports Server (NTRS)

Phen, R. L.; Dowdy, M. W.; Ebbeler, D. H.; Kim. E.-H.; Moore, N. R.; VanZandt, T. R.

1998-01-01

As a result of the concern for the growing number of air-bag-induced injuries and fatalities, the administrators of the National Highway Traffic Safety Administration (NHTSA) and the National Aeronautics and Space Administration (NASA) agreed to a cooperative effort that "leverages NHTSA's expertise in motor vehicle safety restraint systems and biomechanics with NASAs position as one of the leaders in advanced technology development... to enable the state of air bag safety technology to advance at a faster pace..." They signed a NASA/NHTSA memorandum of understanding for NASA to "evaluate air bag to assess advanced air bag performance, establish the technological potential for improved technology (smart) air bag systems, and identify key expertise and technology within the agency (i.e., NASA) that can potentially contribute significantly to the improved effectiveness of air bags." NASA is committed to contributing to NHTSAs effort to: (1) understand and define critical parameters affecting air bag performance; (2) systematically assess air bag technology state of the art and its future potential; and (3) identify new concepts for air bag systems. The Jet Propulsion Laboratory (JPL) was selected by NASA to respond to the memorandum of understanding by conducting an advanced air bag technology assessment. JPL analyzed the nature of the need for occupant restraint, how air bags operate alone and with safety belts to provide restraint, and the potential hazards introduced by the technology. This analysis yielded a set of critical parameters for restraint systems. The researchers examined data on the performance of current air bag technology, and searched for and assessed how new technologies could reduce the hazards introduced by air bags while providing the restraint protection that is their primary purpose. The critical parameters which were derived are: (1) the crash severity; (2) the use of seat belts; (3) the physical characteristics of the occupants; (4) the proximity of the occupants to the airbag module; (5) the deployment time, which includes the time to sense the need for deployment, the inflator response parameters, the air bag response, and the reliability of the air bag. The requirements for an advanced air bag technology is discussed. These requirements includes that the system use information related to: (1) the crash severity; (2) the status of belt usage; (3) the occupant category; and (4) the proximity to the air bag to adjust air bag deployment. The parameters for the response of the air bag are: (1) deployment time; (2) inflator parameters; and (3) air bag response and reliability. The state of occupant protection advanced technology is reviewed. This review includes: the current safety restraint systems, and advanced technology characteristics. These characteristics are summarized in a table, which has information regarding the technology item, the potential, and an date of expected utilization. The use of technology and expertise at NASA centers is discussed. NASA expertise relating to sensors, computing, simulation, propellants, propulsion, inflatable systems, systems analysis and engineering is considered most useful. Specific NASA technology developments, which were included in the study are: (1) a capacitive detector; (2) stereoscopic vision system; (3) improved crash sensors; (4) the use of the acoustic signature of the crash to determine crash severity; and (5) the use of radar antenna for pre-crash sensing. Information relating to injury risk assessment is included, as is a summary of the areas of the technology which requires further development.

Comparison of bacterial attachment to platelet bags with and without preconditioning with plasma.

PubMed

Loza-Correa, M; Kalab, M; Yi, Q-L; Eltringham-Smith, L J; Sheffield, W P; Ramirez-Arcos, S

2017-07-01

Canadian Blood Services produces apheresis and buffy coat pooled platelet concentrates (PCs) stored in bags produced by two different manufacturers (A and B, respectively), both made of polyvinyl chloride-butyryl trihexyl citrate. This study was aimed at comparing Staphylococcus epidermidis adhesion to the inner surface of both bag types in the presence or absence of plasma factors. Sets (N = 2-6) of bags type A and B were left non-coated (control) or preconditioned with platelet-rich, platelet-poor or defibrinated plasma (PRP, PPP and DefibPPP, respectively). Each bag was inoculated with a 200-ml S. epidermidis culture adjusted to 0·5 colony-forming units/ml. Bags were incubated under platelet storage conditions for 7 days. After culture removal, bacteria attached to the plastic surface were either dislodged by sonication for bacterial quantification or examined in situ by scanning electron microscopy (SEM). Higher bacterial adhesion was observed to preconditioned PC bags than control containers for both bag types (P < 0·0001). Bacterial attachment to preconditioned bags was confirmed by SEM. Bacteria adhered equally to both types of containers in the presence of PRP, PPP and DefibPPP residues (P > 0·05). By contrast, a significant increase in bacterial adherence was observed to type A bags compared with type B bags in the absence of plasma (P < 0·05) [Correction added on 16 June 2017, after first online publication: this sentence has been corrected]. The ability of S. epidermidis to adhere to preconditioned platelet collection bags depends on the presence of plasma factors. Future efforts should be focused on reducing plasma proteins' attachment to platelet storage containers to decrease subsequent bacterial adhesion. © 2017 International Society of Blood Transfusion.

Strategy for selecting disposable bags for cell culture media applications based on a root-cause investigation.

PubMed

Wood, Joseph; Mahajan, Ekta; Shiratori, Masaru

2013-01-01

The use of disposable bags for cell culture media storage has grown significantly in the past decade. Some of the key advantages of using disposable bags relative to non-disposable containers include increased product throughput, decreased cleaning validation costs, reduced risk of cross contamination and lower facility costs. As the scope of use of disposable bags for cell culture applications increases, problematic bags and scenarios should be identified and addressed to continue improving disposables technologies and meet the biotech industry's needs. In this article, we examine a cell culture application wherein media stored in disposable bags is warmed at 37°C before use for cell culture operations. A problematic bag film was identified through a prospective and retrospective cell culture investigation. The investigation provided information on the scope and variation of the issue with respect to different Chinese hamster ovary (CHO) cell lines, cell culture media, and application-specific parameters. It also led to the development of application-specific test methods and enabled a strategy for disposable bag film testing. The strategy was implemented for qualifying an alternative bag film for use in our processes. In this test strategy, multiple lots of 13 bag film types, encompassing eight vendors were evaluated using a three round, cell culture-based test strategy. The test strategy resulted in the determination of four viable bag film options based on the technical data. The results of this evaluation were used to conclude that a volatile or air-quenched compound, likely generated by gamma irradiation of the problematic bag film, negatively impacted cell culture performance. © 2013 American Institute of Chemical Engineers.

Bioactive glass fillers reduce bacterial penetration into marginal gaps for composite restorations

PubMed Central

Khvostenko, D.; Hilton, T. J.; Ferracane, J. L.; Mitchell, J. C.; Kruzic, J. J.

2015-01-01

Objectives Bioactive glass (BAG) is known to possess antimicrobial and remineralizing properties; however, the use of BAG as a filler for resin based composite restorations to slow recurrent caries has not been studied. Accordingly, the objective of this study was to investigate the effect of 15 wt% BAG additions to a resin composite on bacterial biofilms penetrating into marginal gaps of simulated tooth fillings in vitro during cyclic mechanical loading. Methods Human molars were machined into approximately 3 mm thick disks of dentin and 1.5–2 mm deep composite restorations were placed. A narrow 15–20 micrometer wide dentin-composite gap was allowed to form along half of the margin by not applying dental adhesive to that region. Two different 72 wt% filled composites were used, one with 15 wt% BAG filler (15BAG) and the balance silanated strontium glass and one filled with OX-50 and silanated strontium glass without BAG (0BAG – control). Samples of both groups had Streptococcus mutans biofilms grown on the surface and were tested inside a bioreactor for two weeks while subjected to periods of cyclic mechanical loading. After post-test biofilm viability was confirmed, each specimen was fixed in glutaraldehyde, gram positive stained, mounted in resin and cross-sectioned to reveal the gap profile. Depth of biofilm penetration for 0BAG and 15BAG was quantified as the fraction of gap depth. The data were compared using a Student’s t-test. Results The average depth of bacterial penetration into the marginal gap for the 15BAG samples was significantly smaller (~61%) in comparison to 0BAG, where 100% penetration was observed for all samples with the biofilm penetrating underneath of the restoration in some cases. Significance BAG containing resin dental composites reduce biofilm penetration into marginal gaps of simulated tooth restorations. This suggests BAG containing composites may have the potential to slow the development and propagation of secondary tooth decay at restoration margins. PMID:26621028

Surface pre-conditioning with bioactive glass air-abrasion can enhance enamel white spot lesion remineralization.

PubMed

Milly, Hussam; Festy, Frederic; Andiappan, Manoharan; Watson, Timothy F; Thompson, Ian; Banerjee, Avijit

2015-05-01

To evaluate the effect of pre-conditioning enamel white spot lesion (WSL) surfaces using bioactive glass (BAG) air-abrasion prior to remineralization therapy. Ninety human enamel samples with artificial WSLs were assigned to three WSL surface pre-conditioning groups (n=30): (a) air-abrasion with BAG-polyacrylic acid (PAA-BAG) powder, (b) acid-etching using 37% phosphoric acid gel (positive control) and (c) unconditioned (negative control). Each group was further divided into three subgroups according to the following remineralization therapy (n=10): (I) BAG paste (36 wt.% BAG), (II) BAG slurry (100 wt.% BAG) and (III) de-ionized water (negative control). The average surface roughness and the lesion step height compared to intra-specimen sound enamel reference points were analyzed using non-contact profilometry. Optical changes within the lesion subsurface compared to baseline scans were assessed using optical coherence tomography (OCT). Knoop microhardness evaluated the WSLs' mechanical properties. Raman micro-spectroscopy measured the v-(CO3)(2-)/v1-(PO4)(3-) ratio. Structural changes in the lesion were observed using confocal laser scanning microscopy (CLSM) and scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX). All comparisons were considered statistically significant if p<0.05. PAA-BAG air-abrasion removed 5.1 ± 0.6 μm from the lesion surface, increasing the WSL surface roughness. Pre-conditioning WSL surfaces with PAA-BAG air-abrasion reduced subsurface light scattering, increased the Knoop microhardness and the mineral content of the remineralized lesions (p<0.05). SEM-EDX revealed mineral depositions covering the lesion surface. BAG slurry resulted in a superior remineralization outcome, when compared to BAG paste. Pre-conditioning WSL surfaces with PAA-BAG air-abrasion modified the lesion surface physically and enhanced remineralization using BAG 45S5 therapy. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Adeno-associated Virus Serotype 9 – Driven Expression of BAG3 Improves Left Ventricular Function in Murine Hearts with Left Ventricular Dysfunction Secondary to a Myocardial Infarction

PubMed Central

Knezevic, Tijana; Myers, Valerie D.; Su, Feifei; Wang, JuFang; Song, Jianliang; Zhang, Xue-Qian; Gao, Erhe; Gao, Guofeng; Muniswamy, Madesh; Gupta, Manish K.; Gordon, Jennifer; Weiner, Kristen N.; Rabinowitz, Joseph; Ramsey, Frederick V.; Tilley, Douglas G.; Khalili, Kamel; Cheung, Joseph Y.; Feldman, Arthur M.

2016-01-01

Objectives The present study was undertaken to test the hypothesis that gene delivery of BCL2-Associated Athanogene 3 (BAG3) to the heart of mice with left ventricular dysfunction secondary to a myocardial infarction could enhance cardiac performance. Background BAG3 is a 575 amino acid protein that has pleotropic functions in the cell including pro-autophagy and anti-apoptosis. Mutations in BAG3 have been associated with both skeletal muscle dysfunction and familial dilated cardiomyopathy and BAG3 levels are diminished in non-familial heart failure. Methods Eight-week-old C57/BL6 mice underwent ligation of the left coronary artery (MI) or sham surgery (Sham). Eight weeks later, mice in both groups were randomly assigned to receive either a retro-orbital injection of rAAV9-BAG3 (MI-BAG3 or Sham-BAG3) or rAAV9-GFP (MI-GFP or Sham GFP). Mice were sacrificed at 3 weeks post-injection and myocytes were isolated from the left ventricle. Results MI-BAG3 mice demonstrated a significantly (p < 0.0001) higher left ventricular ejection fraction (LVEF) 9 days after rAAV9-BAG3 injection with further improvement in LVEF, fractional shortening and stroke volume at 3 weeks post-injection without changes in LV mass or LV volume. Injection of rAAV9-BAG3 had no effect on LVEF in Sham mice. The salutary benefits of rAAV9-BAG3 were also observed in myocytes isolated from MI hearts including improved cell shortening (p<0.05), increased systolic [Ca2+]i, increased [Ca2+]i transient amplitudes and increased maximal ICa amplitude. Implications The results suggest that BAG3 gene therapy may provide a novel therapeutic option for the treatment of heart failure. PMID:28164169

BAG3 promotes the phenotypic transformation of primary rat vascular smooth muscle cells via TRAIL.

PubMed

Fu, Yao; Chang, Ye; Chen, Shuang; Li, Yuan; Chen, Yintao; Sun, Guozhe; Yu, Shasha; Ye, Ning; Li, Chao; Sun, Yingxian

2018-05-01

Under normal physiological condition, the mature vascular smooth muscle cells (VSMCs) show differentiated phenotype. In response to various environmental stimuluses, VSMCs convert from the differentiated phenotype to dedifferentiated phenotype characterized by the increased ability of proliferation/migration and the reduction of contractile ability. The phenotypic transformation of VSMCs played an important role in atherosclerosis. Both Bcl-2-associated athanogene 3 (BAG3) and tumor necrosis factor-related apopt-osis inducing ligand (TRAIL) involved in apoptosis. The relationship between BAG3 and TRAIL and their effects the proliferation and migration in VSMCs are rarely reported. This study investigated the effects of BAG3 on the phenotypic modulation and the potential underlying mechanisms in primary rat VSMCs. Primary rat VSMCs were extracted and cultured in vitro. Cell proliferation was detected by cell counting, real-time cell analyzer (RTCA) and EdU incorporation. Cell migration was detected by wound healing, Transwell and RTCA. BAG3 and TRAIL were detected using real-time PCR and western blotting and the secreted proteins in the cultured media by dot blot. The expression of BAG3 increased with continued passages in cultured primary VSMCs. BAG3 promoted the proliferation and migration of primary rat VSMC in a time-dependent manner. BAG3 significantly increased the expression of TRAIL while had no effects on its receptors. TRAIL knockdown or blocking by neutralizing antibody inhibited the proliferation of VSMCs induced by BAG3. TRAIL knockdown exerted no obvious influence on the migration of VSMCs. Based on this study, we report for the first time that BAG3 was expressed in cultured primary rat VSMCs and the expression of BAG3 increased with continued passages. Furthermore, BAG3 promoted the proliferation of VSMCs via increasing the expression of TRAIL. In addition, we also demonstrated that BAG3 promoted the migration of VSMCs independent of TRAIL upregulation.

HSPB8 and BAG3 cooperate to promote spatial sequestration of ubiquitinated proteins and coordinate the cellular adaptive response to proteasome insufficiency.

PubMed

Guilbert, Solenn M; Lambert, Herman; Rodrigue, Marc-Antoine; Fuchs, Margit; Landry, Jacques; Lavoie, Josée N

2018-02-05

BCL2-associated athanogene (BAG)-3 is viewed as a platform that would physically and functionally link distinct classes of molecular chaperones of the heat shock protein (HSP) family for the stabilization and clearance of damaged proteins. In this study, we show that HSPB8, a member of the small heat shock protein subfamily, cooperates with BAG3 to coordinate the sequestration of harmful proteins and the cellular adaptive response upon proteasome inhibition. Silencing of HSPB8, like depletion of BAG3, inhibited targeting of ubiquitinated proteins to the juxtanuclear aggresome, a mammalian system of spatial quality control. However, aggresome targeting was restored in BAG3-depleted cells by a mutant BAG3 defective in HSPB8 binding, uncoupling HSPB8 function from its binding to BAG3. Depletion of HSPB8 impaired formation of ubiquitinated microaggregates in an early phase and interfered with accurate modifications of the stress sensor p62/sequestosome (SQSTM)-1. This impairment correlated with decreased coupling of BAG3 to p62/SQSTM1 in response to stress, hindering Kelch-like ECH-associated protein (KEAP)-1 sequestration and stabilization of nuclear factor E2-related factor (Nrf)-2, an important arm of the antioxidant defense. Notably, the myopathy-associated mutation of BAG3 (P209L), which lies within the HSPB8-binding motif, deregulated the association between BAG3 and p62/SQSTM1 and the KEAP1-Nrf2 signaling axis. Together, our findings support a so-far-unrecognized role for the HSPB8-BAG3 connection in mounting of an efficient stress response, which may be involved in BAG3-related human diseases.-Guilbert, S. M., Lambert, H., Rodrigue, M.-A., Fuchs, M., Landry, J., Lavoie, J. N. HSPB8 and BAG3 cooperate to promote spatial sequestration of ubiquitinated proteins and coordinate the cellular adaptive response to proteasome insufficiency.

Adeno-associated Virus Serotype 9 - Driven Expression of BAG3 Improves Left Ventricular Function in Murine Hearts with Left Ventricular Dysfunction Secondary to a Myocardial Infarction.

PubMed

Knezevic, Tijana; Myers, Valerie D; Su, Feifei; Wang, JuFang; Song, Jianliang; Zhang, Xue-Qian; Gao, Erhe; Gao, Guofeng; Muniswamy, Madesh; Gupta, Manish K; Gordon, Jennifer; Weiner, Kristen N; Rabinowitz, Joseph; Ramsey, Frederick V; Tilley, Douglas G; Khalili, Kamel; Cheung, Joseph Y; Feldman, Arthur M

2016-12-01

The present study was undertaken to test the hypothesis that gene delivery of BCL2-Associated Athanogene 3 (BAG3) to the heart of mice with left ventricular dysfunction secondary to a myocardial infarction could enhance cardiac performance. BAG3 is a 575 amino acid protein that has pleotropic functions in the cell including pro-autophagy and anti-apoptosis. Mutations in BAG3 have been associated with both skeletal muscle dysfunction and familial dilated cardiomyopathy and BAG3 levels are diminished in non-familial heart failure. Eight-week-old C57/BL6 mice underwent ligation of the left coronary artery (MI) or sham surgery (Sham). Eight weeks later, mice in both groups were randomly assigned to receive either a retro-orbital injection of rAAV9-BAG3 (MI-BAG3 or Sham-BAG3) or rAAV9-GFP (MI-GFP or Sham GFP). Mice were sacrificed at 3 weeks post-injection and myocytes were isolated from the left ventricle. MI-BAG3 mice demonstrated a significantly (p < 0.0001) higher left ventricular ejection fraction (LVEF) 9 days after rAAV9-BAG3 injection with further improvement in LVEF, fractional shortening and stroke volume at 3 weeks post-injection without changes in LV mass or LV volume. Injection of rAAV9-BAG3 had no effect on LVEF in Sham mice. The salutary benefits of rAAV9-BAG3 were also observed in myocytes isolated from MI hearts including improved cell shortening (p<0.05), increased systolic [Ca 2+ ] i , increased [Ca 2+ ] i transient amplitudes and increased maximal I Ca amplitude. The results suggest that BAG3 gene therapy may provide a novel therapeutic option for the treatment of heart failure.

49 CFR 178.518 - Standards for woven plastic bags.

Code of Federal Regulations, 2011 CFR

2011-10-01

... plastic bag; (2) 5H2 for a sift-proof woven plastic bag; and (3) 5H3 for a water-resistant woven plastic... other equally strong method of closure. (3) Bags, sift-proof, 5H2 must be made sift-proof by appropriate...

Vented spikes improve delivery from intravenous bags with no air headspace.

PubMed

Galush, William J; Horst, Travis A

2015-07-01

Flexible plastic bags are the container of choice for most intravenous (i.v.) infusions. Under certain circumstances, however, the air-liquid interface present in these i.v. bags can lead to physical instability of protein biopharmaceuticals, resulting in product aggregation. In principle, the air headspace present in the bags can be removed to increase drug stability, but experiments described here show that this can result in incomplete draining of solution from the bag using gravity delivery, or generation of negative pressure in the bag when an infusion pump is used. It is expected that these issues could lead to incomplete delivery of medication to patients or pump-related problems, respectively. However, here it is shown that contrary to the standard pharmacy practice of using nonvented spikes with i.v. bags, the use of vented spikes with i.v. bags that lack air headspace allows complete delivery of the dose solution without impacting the physical stability of a protein-based drug. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

HIV-1 Tat protein induces glial cell autophagy through enhancement of BAG3 protein levels.

PubMed

Bruno, Anna Paola; De Simone, Francesca Isabella; Iorio, Vittoria; De Marco, Margot; Khalili, Kamel; Sariyer, Ilker Kudret; Capunzo, Mario; Nori, Stefania Lucia; Rosati, Alessandra

2014-01-01

BAG3 protein has been described as an anti-apoptotic and pro-autophagic factor in several neoplastic and normal cells. We previously demonstrated that BAG3 expression is elevated upon HIV-1 infection of glial and T lymphocyte cells. Among HIV-1 proteins, Tat is highly involved in regulating host cell response to viral infection. Therefore, we investigated the possible role of Tat protein in modulating BAG3 protein levels and the autophagic process itself. In this report, we show that transfection with Tat raises BAG3 levels in glioblastoma cells. Moreover, BAG3 silencing results in highly reducing Tat- induced levels of LC3-II and increasing the appearance of sub G0/G1 apoptotic cells, in keeping with the reported role of BAG3 in modulating the autophagy/apoptosis balance. These results demonstrate for the first time that Tat protein is able to stimulate autophagy through increasing BAG3 levels in human glial cells.

Effectiveness of oxygen barrier oven bags in low temperature cooking on reduction of warmed-over flavor in beef roasts.

PubMed

Lepper-Blilie, A N; Berg, E P; Buchanan, D S; Keller, W L; Maddock-Carlin, K R; Berg, P T

2014-03-01

A 3×3×2 factorial was utilized to determine if roast size (small, medium, large), cooking method (open-pan, oven bag, vacuum bag), and heating process (fresh, reheated) prevented warmed-over flavor (WOF) in beef clod roasts. Fresh vacuum bag and reheated open-pan roasts had higher cardboardy flavor scores compared with fresh open-pan roast scores. Reheated roasts in oven and vacuum bags did not differ from fresh roasts for cardboardy flavor. Brothy and fat intensity were increased in reheated roasts in oven and vacuum bags compared with fresh roasts in oven and vacuum bags. Differences in TBARS were found in the interaction of heating process and roast size with the fresh and reheated large, and reheated medium roasts having the lowest values. Based on TBARS data, to prevent WOF in reheated beef roasts, a larger size roast in a cooking bag is the most effective method. Copyright © 2013 Elsevier Ltd. All rights reserved.

Large thermal protection system panel

NASA Technical Reports Server (NTRS)

Weinberg, David J. (Inventor); Myers, Franklin K. (Inventor); Tran, Tu T. (Inventor)

2003-01-01

A protective panel for a reusable launch vehicle provides enhanced moisture protection, simplified maintenance, and increased temperature resistance. The protective panel includes an outer ceramic matrix composite (CMC) panel, and an insulative bag assembly coupled to the outer CMC panel for isolating the launch vehicle from elevated temperatures and moisture. A standoff attachment system attaches the outer CMC panel and the bag assembly to the primary structure of the launch vehicle. The insulative bag assembly includes a foil bag having a first opening shrink fitted to the outer CMC panel such that the first opening and the outer CMC panel form a water tight seal at temperatures below a desired temperature threshold. Fibrous insulation is contained within the foil bag for protecting the launch vehicle from elevated temperatures. The insulative bag assembly further includes a back panel coupled to a second opening of the foil bag such that the fibrous insulation is encapsulated by the back panel, the foil bag, and the outer CMC panel. The use of a CMC material for the outer panel in conjunction with the insulative bag assembly eliminates the need for waterproofing processes, and ultimately allows for more efficient reentry profiles.

BAG3 Directly Interacts with Mutated alphaB-Crystallin to Suppress Its Aggregation and Toxicity

PubMed Central

Hishiya, Akinori; Salman, Mortada Najem; Carra, Serena; Kampinga, Harm H.; Takayama, Shinichi

2011-01-01

A homozygous disruption or genetic mutation of the bag3 gene causes progressive myofibrillar myopathy in mouse and human skeletal and cardiac muscle disorder while mutations in the small heat shock protein αB-crystallin gene (CRYAB) are reported to be responsible for myofibrillar myopathy. Here, we demonstrate that BAG3 directly binds to wild-type αB-crystallin and the αB-crystallin mutant R120G, via the intermediate domain of BAG3. Peptides that inhibit this interaction in an in vitro binding assay indicate that two conserved Ile-Pro-Val regions of BAG3 are involved in the interaction with αB-crystallin, which is similar to results showing BAG3 binding to HspB8 and HspB6. BAG3 overexpression increased αB-crystallin R120G solubility and inhibited its intracellular aggregation in HEK293 cells. BAG3 suppressed cell death induced by αB-crystallin R120G overexpression in differentiating C2C12 mouse myoblast cells. Our findings indicate a novel function for BAG3 in inhibiting protein aggregation caused by the genetic mutation of CRYAB responsible for human myofibrillar myopathy. PMID:21423662

BAG3 regulates ECM accumulation in renal proximal tubular cells induced by TGF-β1.

PubMed

Du, Feng; Li, Si; Wang, Tian; Zhang, Hai-Yan; Li, De-Tian; Du, Zhen-Xian; Wang, Hua-Qin; Wang, Yan-Qiu

2015-01-01

Previously we have demonstrated that Bcl-2-associated athanogene 3 (BAG3) is increased in renal fibrosis using a rat unilateral ureteral obstruction model. The current study investigated the role of BAG3 in renal fibrosis using transforming growth factor (TGF)-β1-treated human proximal tubular epithelial (HK-2) cells. An upregulation of BAG3 in vitro models was observed, which correlated with the increased synthesis of extracellular matrix (ECM) proteins and expression of tissue-type plasminogen activator inhibitor (PAI)-1. Blockade of BAG3 induction by shorting hairpin RNA suppressed the expression of ECM proteins but had no effect on PAI-1 expression induced by TGF-β1. Forced overexpression of BAG3 selectively increased collagens. TGF-β1-induced BAG3 expression in HK-2 cells was attenuated by ERK1/2 and JNK MAPK inhibitors. In addition, forced BAG3 overexpression blocked attenuation of collagens expression by ERK1/2 and JNK inhibitors. These data suggest that ERK1/2 and JNK signaling events are involved in modulating the expression of BAG3, which would ultimately contribute to renal fibrosis by enhancing the synthesis and deposition of ECM proteins.

BAG3 regulates ECM accumulation in renal proximal tubular cells induced by TGF-β1

PubMed Central

Du, Feng; Li, Si; Wang, Tian; Zhang, Hai-Yan; Li, De-Tian; Du, Zhen-Xian; Wang, Hua-Qin; Wang, Yan-Qiu

2015-01-01

Previously we have demonstrated that Bcl-2-associated athanogene 3 (BAG3) is increased in renal fibrosis using a rat unilateral ureteral obstruction model. The current study investigated the role of BAG3 in renal fibrosis using transforming growth factor (TGF)-β1-treated human proximal tubular epithelial (HK-2) cells. An upregulation of BAG3 in vitro models was observed, which correlated with the increased synthesis of extracellular matrix (ECM) proteins and expression of tissue-type plasminogen activator inhibitor (PAI)-1. Blockade of BAG3 induction by shorting hairpin RNA suppressed the expression of ECM proteins but had no effect on PAI-1 expression induced by TGF-β1. Forced overexpression of BAG3 selectively increased collagens. TGF-β1-induced BAG3 expression in HK-2 cells was attenuated by ERK1/2 and JNK MAPK inhibitors. In addition, forced BAG3 overexpression blocked attenuation of collagens expression by ERK1/2 and JNK inhibitors. These data suggest that ERK1/2 and JNK signaling events are involved in modulating the expression of BAG3, which would ultimately contribute to renal fibrosis by enhancing the synthesis and deposition of ECM proteins. PMID:26885277

Overhead work and shoulder-neck pain in orchard farmers harvesting pears and apples.

PubMed

Sakakibara, H; Miyao, M; Kondo, T; Yamada, S

1995-04-01

The effects of overhead work were studied by comparing orchard farmers' musculoskeletal symptoms while bagging pears with those same symptoms while bagging apples. The subjects were 52 Japanese female farmers, who were examined twice an evening in late June for bagging pears, and during another evening of late July for bagging apples, when each task had been almost finished. They were questioned about musculoskeletal complaints of stiffness and pain during each job, and examined for muscle tenderness and pain from joint movement. Arm elevation angles during the work were measured for each type of bagging. The prevalence of stiffness and pain in the neck and shoulder, muscle tenderness in the shoulder regions, and pain in neck motion were found to be significantly higher when bagging pears than apples. Musculoskeletal symptoms of parts other than the neck and shoulder did not differ between the two types of bagging. The working posture of elevating the arm more than 90 degrees was assumed to account for 75% of the time bagging pears, against 40% for bagging apples. Overhead work requiring arm elevation and head extension was considered to be closely related with shoulder-neck disorders among farmers.

An overview of frontal air bag performance with changes in frontal crash-test requirements: findings of the Blue Ribbon Panel for the evaluation of advanced technology air bags.

PubMed

Ferguson, Susan A; Schneider, Lawrence W

2008-10-01

In the mid-1990s, evidence emerged that air bag deployments could result in deaths to vulnerable vehicle occupants who were very close to air bag modules when they deployed. In 1997, federal frontal crash test requirements were modified to allow crash testing with unbelted dummies to be performed using sled tests. As a result, vehicle manufacturers were able to redesign air bags to deploy with less force and energy, thereby reducing the toll of air bag-induced deaths. However, there was concern that depowered air bags may not provide the same level of protection to unbelted occupants in severe frontal crashes, particularly occupants of large stature and body mass. This paper provides a summary of recent studies addressing this issue. To expedite the accrual of data regarding air bag performance, the collection of additional crash data was funded by the Alliance of Automobile Manufacturers. A panel of experts was commissioned to oversee the process and evaluate the data. During the past 6 years, a series of studies has been undertaken by panel members and others to evaluate the performance of redesigned air bags and the data are summarized here. There is now convincing evidence that the combination of air bag redesign and public education have resulted in dramatic reductions in air bag-induced infant and child deaths. In addition, the frontal crash fatality risks among children sitting in front seats have been reduced by as much as half, with younger children showing the greatest benefits. Among adult drivers and right-front passengers, there is no evidence for the predicted overall loss of protection with sled-certified air bags and there are far fewer air bag-induced deaths among this population. However, despite exhaustive analyses of frontal-crash data, the possibility of a somewhat elevated fatality risk among a subset of unbelted drivers in sled-certified 1998-1999 model vehicles cannot be ruled out. There also is some evidence that the risks of serious chest injury may be higher among unbelted drivers in frontal crashes in sled-certified vehicles with redesigned air bags. Further research is warranted to determine whether these differences remain in newer model vehicles designed to the advanced air bag rule, which took effect in 2003.

Vehicle safety : technologies, challenges, and research and development expenditures for advanced air bags

DOT National Transportation Integrated Search

2001-06-01

One hundred seventy five fatalities - primarily children and small women - have been attributed to the deployment of an air bag in relatively low-speed crashes as of April 2001. Advanced air bag systems tailor the deployment of the bags to the charac...

Examination of factors dominating the sediment-water diffusion flux of DDT-related compounds measured by passive sampling in an urbanized estuarine bay.

PubMed

Feng, Yan; Wu, Chen-Chou; Bao, Lian-Jun; Shi, Lei; Song, Lin; Zeng, Eddy Y

2016-12-01

The fate of hydrophobic organic compounds in aquatic environment are largely determined by their exchange at sediment-water interface, which is highly dynamic and subject to rapidly evolving environmental conditions. In turn, environmental conditions may be governed by both physicochemical parameters and anthropogenic events. To examine the importance of various impact factors, passive sampling devices were deployed at the seafloor of Hailing Bay, an urbanized estuarine bay in Guangdong Province of South China to measure the sediment-water diffusion fluxes of several metabolites of dichlorodiphenyltrichloroethane (DDT), p,p'-DDE, p,p'-DDD and o,p'-DDD. The physicochemical properties of water (temperature, pH, salinity and dissolved oxygen) and surface sediment (sediment organic matter, physical composition, pH, water content, colony forming unit and catalase activity) were also measured. The results showed that the diffusion fluxes of o,p'-DDD, p,p'-DDD and p,p'-DDE at sites A1 and A2 near a fishing boat maintenance facility ranged from 0.42 to 4.73 ng m -2 d -1 (from sediment to overlying water), whereas those at offshore sites varied between -0.03 and -3.02 ng m -2 d -1 (from overlying water to sediment), implicating A1 and A2 as the sources of the target compounds. The distribution patterns of the diffusion fluxes of the target compounds were different from those of water and sediment parameters (water temperature, salinity, sediment texture, pH, colony forming unit and catalase activity) at six sampling sites. This finding suggested that none of these parameters were critical in dictating the sediment-water diffusion fluxes. Besides, decreases in the contents of kerogen and black carbon by 6.7% and 11% would enhance the diffusion fluxes of the target compounds by 11-14% and 12-23%, respectively, at site A1, indicating that kerogen and black carbon were the key factors in mediating the sediment-water diffusion fluxes of DDT-related compounds in field environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evidence for the Role of BAG3 in Mitochondrial Quality Control in Cardiomyocytes.

PubMed

Tahrir, Farzaneh G; Knezevic, Tijana; Gupta, Manish K; Gordon, Jennifer; Cheung, Joseph Y; Feldman, Arthur M; Khalili, Kamel

2017-04-01

Mitochondrial abnormalities impact the development of myofibrillar myopathies. Therefore, understanding the mechanisms underlying the removal of dysfunctional mitochondria from cells is of great importance toward understanding the molecular events involved in the genesis of cardiomyopathy. Earlier studies have ascribed a role for BAG3 in the development of cardiomyopathy in experimental animals leading to the identification of BAG3 mutations in patients with heart failure which may play a part in the onset of disease development and progression. BAG3 is co-chaperone of heat shock protein 70 (HSP70), which has been shown to modulate apoptosis and autophagy, in several cell models. In this study, we explore the potential role of BAG3 in mitochondrial quality control. We demonstrate that siRNA mediated suppression of BAG3 production in neonatal rat ventricular cardiomyocytes (NRVCs) significantly elevates the level of Parkin, a key component of mitophagy. We found that both BAG3 and Parkin are recruited to depolarized mitochondria and promote mitophagy. Suppression of BAG3 in NRVCs significantly reduces autophagy flux and eliminates clearance of Tom20, an essential import receptor for mitochondria proteins, after induction of mitophagy. These observations suggest that BAG3 is critical for the maintenance of mitochondrial homeostasis under stress conditions, and disruptions in BAG3 expression impact cardiomyocyte function. J. Cell. Physiol. 232: 797-805, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Stable isotope ratio mass spectrometry and physical comparison for the forensic examination of grip-seal plastic bags.

PubMed

Taylor, Erica; Carter, James F; Hill, Jenny C; Morton, Carolyn; Daeid, Niamh Nic; Sleeman, Richard

2008-05-20

Plastic bags are frequently used to package drugs, explosives and other contraband. There exists, therefore, a requirement in forensic casework to compare bags found at different locations. This is currently achieved almost exclusively by the use of physical comparisons such as birefringence patterns. This paper discusses some of the advantages and shortcomings of this approach, and presents stable isotope ratio mass spectrometry (IRMS) as a supplementary tool for effecting comparisons of this nature. Carbon and hydrogen isotopic data are presented for sixteen grip-seal plastic bags from a wide range of sources, in order to demonstrate the range of values which is likely to be encountered. Both isotopic and physical comparison (specifically birefringence) techniques are then applied to the analysis of rolls of bags from different manufacturing lots from a leading manufacturer. Both approaches are able to associate bags from a common production batch. IRMS can be applied to small fragments which are not amenable to physical comparisons, and is able to discriminate bags which could be confused using birefringence patterns alone. Similarly, in certain cases birefringence patterns discriminate bags with similar isotopic compositions. The two approaches are therefore complementary. When more than one isotopically distinct region exists within a bag (e.g. the grip-seal is distinct from the body) the ability to discriminate and associate bags is greatly increased.

ALD TiO x as a top-gate dielectric and passivation layer for InGaZnO115 ISFETs

NASA Astrophysics Data System (ADS)

Pavlidis, S.; Bayraktaroglu, B.; Leedy, K.; Henderson, W.; Vogel, E.; Brand, O.

2017-11-01

The suitability of atomic layer deposited (ALD) titanium oxide (TiO x ) as a top gate dielectric and passivation layer for indium gallium zinc oxide (InGaZnO115) ion sensitive field effect transistors (ISFETs) is investigated. TiO x is an attractive barrier material, but reports of its use for InGaZnO thin film transistor (TFT) passivation have been conflicting thus far. In this work, it is found that the passivated TFT’s behavior depends on the TiO x deposition temperature, affecting critical device characteristics such as threshold voltage, field-effect mobility and sub-threshold swing. An O2 annealing step is required to recover TFT performance post passivation. It is also observed that the positive bias stress response of the passivated TFTs improves compared the original bare device. Secondary ion mass spectroscopy excludes the effects of hydrogen doping and inter-diffusion as sources of the temperature-dependent performance change, therefore indicating that oxygen gettering induced by TiO x passivation is the likely source of oxygen vacancies and, consequently, carriers in the InGaZnO film. It is also shown that potentiometric sensing using ALD TiO x exhibits a near Nernstian response to pH change, as well as minimizes V TH drift in TiO x passivated InGaZnO TFTs immersed in an acidic liquid. These results add to the understanding of InGaZnO passivation effects and underscore the potential for low-temperature fabricated InGaZnO ISFETs to be used as high-performance mobile chemical sensors.

Improved extension of platelet storage in a polyolefin container with higher oxygen permeability.

PubMed

Yuasa, Takeshi; Ohto, Hitoshi; Yasunaga, Reiko; Kai, Takanori; Shirahama, Noriaki; Ogata, Takashi

2004-07-01

This study evaluated a newly developed polyolefin bag, which has a 50%/m(2) higher oxygen permeability to extend the shelf-life of platelets. Single-donor aphaeresis platelets were pooled, separated equally into two bags, PO-80 (0.8 l capacity) and KBP-PO (1 l capacity) for control, and stored in plasma for up to 7 d. Platelet biochemical and functional parameters were monitored in bags containing high (4.2 x 10(11)/250 ml/bag, n = 9) and low (2.0 x 10(11)/200 ml/bag, n = 3) concentrations of platelets over the storage period. After 7 d of storage, the PO-80 bags containing high concentrations of platelets had a better pH (mean pH 6.74) than those stored in KBP-PO (pH 6.32, P < 0.01); none of the nine PO-80 bags with a high platelet concentration had a pH below 6.2, compared with four of nine controls (P < 0.05). Similarly, lactate values were 20.19 mmol/l and 28.09 mmol/l respectively (P < 0.05). Aerobic metabolism was maintained better with greater O(2) consumption and less lactate generation in high-platelet concentration PO-80 bags than in the control bags. A significant difference was also found in pH, pCO(2) and lactate levels between the two bags containing low concentrations of platelets during the 7-d period. The in vitro characteristics of platelets declined less over 7 d when stored in a higher oxygen permeable container than in a marketed bag.

The prosurvival protein BAG3: a new participant in vascular homeostasis

PubMed Central

Carrizzo, Albino; Damato, Antonio; Ambrosio, Mariateresa; Falco, Antonia; Rosati, Alessandra; Capunzo, Mario; Madonna, Michele; Turco, Maria C; Januzzi, James L; De Laurenzi, Vincenzo; Vecchione, Carmine

2016-01-01

Bcl2-associated athanogene 3 (BAG3), is constitutively expressed in a few normal cell types, including myocytes, peripheral nerves and in the brain, and is also expressed in certain tumors. To date, the main studies about the role of BAG3 are focused on its pro-survival effect in tumors through various mechanisms that vary according to cellular type. Recently, elevated concentrations of a soluble form of BAG3 were described in patients affected by advanced stage of heart failure (HF), identifying BAG3 as a potentially useful biomarker in monitoring HF progression. Despite the finding of high levels of BAG3 in the sera of HF patients, there are no data on its possible role on the modulation of vascular tone and blood pressure levels. The aim of this study was to investigate the possible hemodynamic effects of BAG3 performing both in vitro and in vivo experiments. Through vascular reactivity studies, we demonstrate that BAG3 is capable of evoking dose-dependent vasorelaxation. Of note, BAG3 exerts its vasorelaxant effect on resistance vessels, typically involved in the blood pressure regulation. Our data further show that the molecular mechanism through which BAG3 exerts this effect is the activation of the PI3K/Akt signalling pathway leading to nitric oxide release by endothelial cells. Finally, we show that in vivo BAG3 administration is capable of regulating blood pressure and that this is dependent on eNOS regulation since this ability is lost in eNOS KO animals. PMID:27763645

BAG3-mediated Mcl-1 stabilization contributes to drug resistance via interaction with USP9X in ovarian cancer.

PubMed

Habata, Shutaro; Iwasaki, Masahiro; Sugio, Asuka; Suzuki, Miwa; Tamate, Masato; Satohisa, Seiro; Tanaka, Ryoichi; Saito, Tsuyoshi

2016-07-01

Paclitaxel in combination with carboplatin improves survival among patients with susceptible ovarian cancers, but no strategy has been established against resistant ovarian cancers. BAG3 (Bcl-2-associated athanogene 3) is one of six BAG family proteins, which are involved in such cellular processes as proliferation, migration and apoptosis. In addition, expression of BAG3 with Mcl-1, a Bcl-2 family protein, reportedly associates with resistance to chemotherapy. Our aim in this study was to evaluate the functional role of BAG3 and Mcl-1 in ovarian cancer chemoresistance and explore possible new targets for treatment. We found that combined expression of BAG3 and Mcl-1 was significantly associated with a poor prognosis in ovarian cancer patients. In vitro, BAG3 knockdown in ES2 clear ovarian cancer cells significantly increased the efficacy of paclitaxel in combination with the Mcl-1 antagonist MIM1, with or without the Bcl-2 family antagonist ABT737. Moreover, BAG3 was found to positively regulate Mcl-1 levels by binding to and inhibiting USP9X. Our data show that BAG3 and Mcl-1 are key mediators of resistance to chemotherapy in ovarian cancer. In BAG3 knockdown ES2 clear ovarian cancer cells, combination with ABT737 and MIM1 enhanced the efficacy of paclitaxel. These results suggest that inhibiting BAG3 in addition to anti-apoptotic Bcl-2 family proteins may be a useful therapeutic strategy for the treatment of chemoresistant ovarian cancers.

Acceptance test report, 241-SY-101 Flexible Receiver System, Phase 2 testing

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

Ritter, G.A.

1995-02-06

This document summarizes the results of the Phase 2 acceptance test of the 241-SY-101 Flexible Receiver System (FRS). The FRS is one of six major components of the Equipment Removal System, which has been designed to retrieve, transport, and store the test mixer pump currently installed in Tank 241-SY-101. The purpose of this acceptance test is to verify the strength of the containment bag and bag bottom cinching mechanism. It is postulated that 68 gallons of waste could be trapped inside the pump internals. The bag must be capable of supporting this waste if it shakes loose and drains tomore » the bottom of the bag after the bag bottom has been cinched closed. This acceptance test was performed at the Maintenance and Storage Facility (MASF) Facility in the 400 area on January 23, 1995. The bag assembly supported the weight of 920 kg (2,020 lbs) of water with no leakage or damage to the bag. This value meets the acceptance criteria of 910 kg of water and therefore the results were found to be acceptable. The maximum volume of liquid expected to be held up in the pump internals is 258 L (68 gallons), which corresponds to 410 kg. This test weight gives just over a safety factor of 2. The bag also supported a small shock load while it was filled with water when the crane hoisted the bag assembly up and down. Based on the strength rating of the bag components, the bag assembly should support 2--3 times the test weight of 910 kg.« less

Processes for producing low cost, high efficiency silicon solar cells

DOEpatents

Rohatgi, Ajeet; Chen, Zhizhang; Doshi, Parag

1996-01-01

Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. Silicon solar cell efficiencies of 16.9% have been achieved. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x.

76 FR 59999 - Polyethylene Retail Carrier Bags From Thailand: Final Results of Antidumping Duty Administrative...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-28

... Bags From Thailand: Final Results of Antidumping Duty Administrative Review AGENCY: Import... antidumping duty order on polyethylene retail carrier bags from Thailand. We gave interested parties an... Bags From Thailand: Preliminary Results of Antidumping Duty Administrative Review, 76 FR 30102 (May 24...

21 CFR 870.3650 - Pacemaker polymeric mesh bag.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Pacemaker polymeric mesh bag. 870.3650 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3650 Pacemaker polymeric mesh bag. (a) Identification. A pacemaker polymeric mesh bag is an implanted device used to hold a...

21 CFR 870.3650 - Pacemaker polymeric mesh bag.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Pacemaker polymeric mesh bag. 870.3650 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3650 Pacemaker polymeric mesh bag. (a) Identification. A pacemaker polymeric mesh bag is an implanted device used to hold a...

21 CFR 870.3650 - Pacemaker polymeric mesh bag.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pacemaker polymeric mesh bag. 870.3650 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3650 Pacemaker polymeric mesh bag. (a) Identification. A pacemaker polymeric mesh bag is an implanted device used to hold a...

21 CFR 870.3650 - Pacemaker polymeric mesh bag.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Pacemaker polymeric mesh bag. 870.3650 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3650 Pacemaker polymeric mesh bag. (a) Identification. A pacemaker polymeric mesh bag is an implanted device used to hold a...

50 CFR 660.721 - Recreational fishing bag limits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Recreational fishing bag limits. 660.721... Migratory Fisheries § 660.721 Recreational fishing bag limits. This section applies to recreational fishing... daily bag limit of fishing during one calendar day. Federal recreational HMS regulations are not...

50 CFR 660.721 - Recreational fishing bag limits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Recreational fishing bag limits. 660.721... Migratory Fisheries § 660.721 Recreational fishing bag limits. This section applies to recreational fishing... daily bag limit of fishing during one calendar day. Federal recreational HMS regulations are not...

50 CFR 660.721 - Recreational fishing bag limits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Recreational fishing bag limits. 660.721... Migratory Fisheries § 660.721 Recreational fishing bag limits. This section applies to recreational fishing... daily bag limit of fishing during one calendar day. Federal recreational HMS regulations are not...

50 CFR 660.721 - Recreational fishing bag limits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Recreational fishing bag limits. 660.721... Migratory Fisheries § 660.721 Recreational fishing bag limits. This section applies to recreational fishing... daily bag limit of fishing during one calendar day. Federal recreational HMS regulations are not...

50 CFR 660.721 - Recreational fishing bag limits.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Recreational fishing bag limits. 660.721... Migratory Fisheries § 660.721 Recreational fishing bag limits. This section applies to recreational fishing... daily bag limit of fishing during one calendar day. Federal recreational HMS regulations are not...

21 CFR 868.5320 - Reservoir bag.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Reservoir bag. 868.5320 Section 868.5320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5320 Reservoir bag. (a) Identification. A reservoir bag is a...

21 CFR 868.5320 - Reservoir bag.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Reservoir bag. 868.5320 Section 868.5320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5320 Reservoir bag. (a) Identification. A reservoir bag is a...

49 CFR 552.12 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... of an air bag system that automatically controls whether or not the air bag deploys during a crash by: (1) Sensing the location of an occupant, moving or still, in relation to the air bag; (2) Interpreting the occupant characteristics and location information to determine whether or not the air bag...

49 CFR 552.12 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... of an air bag system that automatically controls whether or not the air bag deploys during a crash by: (1) Sensing the location of an occupant, moving or still, in relation to the air bag; (2) Interpreting the occupant characteristics and location information to determine whether or not the air bag...

49 CFR 552.12 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... of an air bag system that automatically controls whether or not the air bag deploys during a crash by: (1) Sensing the location of an occupant, moving or still, in relation to the air bag; (2) Interpreting the occupant characteristics and location information to determine whether or not the air bag...

49 CFR 552.12 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... of an air bag system that automatically controls whether or not the air bag deploys during a crash by: (1) Sensing the location of an occupant, moving or still, in relation to the air bag; (2) Interpreting the occupant characteristics and location information to determine whether or not the air bag...

Passive ultrasonics using sub-Nyquist sampling of high-frequency thermal-mechanical noise.

PubMed

Sabra, Karim G; Romberg, Justin; Lani, Shane; Degertekin, F Levent

2014-06-01

Monolithic integration of capacitive micromachined ultrasonic transducer arrays with low noise complementary metal oxide semiconductor electronics minimizes interconnect parasitics thus allowing the measurement of thermal-mechanical (TM) noise. This enables passive ultrasonics based on cross-correlations of diffuse TM noise to extract coherent ultrasonic waves propagating between receivers. However, synchronous recording of high-frequency TM noise puts stringent requirements on the analog to digital converter's sampling rate. To alleviate this restriction, high-frequency TM noise cross-correlations (12-25 MHz) were estimated instead using compressed measurements of TM noise which could be digitized at a sampling frequency lower than the Nyquist frequency.

Interpreting the Weibull fitting parameters for diffusion-controlled release data

NASA Astrophysics Data System (ADS)

Ignacio, Maxime; Chubynsky, Mykyta V.; Slater, Gary W.

2017-11-01

We examine the diffusion-controlled release of molecules from passive delivery systems using both analytical solutions of the diffusion equation and numerically exact Lattice Monte Carlo data. For very short times, the release process follows a √{ t } power law, typical of diffusion processes, while the long-time asymptotic behavior is exponential. The crossover time between these two regimes is determined by the boundary conditions and initial loading of the system. We show that while the widely used Weibull function provides a reasonable fit (in terms of statistical error), it has two major drawbacks: (i) it does not capture the correct limits and (ii) there is no direct connection between the fitting parameters and the properties of the system. Using a physically motivated interpolating fitting function that correctly includes both time regimes, we are able to predict the values of the Weibull parameters which allows us to propose a physical interpretation.

Seat belt use in cars with air bags.

PubMed Central

Williams, A F; Wells, J K; Lund, A K

1990-01-01

Seat belt use was observed in 1,628 cars with air bags and manual belts and 34,223 cars with manual seat belts only. Sixty-six percent of drivers in cars with air bags wore seat belts compared to 63 percent of drivers in cars with manual belts only. The study found no evidence for the speculation that drivers with air bags will reduce their seat belt use because they believe an air bag alone provides sufficient protection. PMID:2240346

Underwater seismic source. [for petroleum exploration

NASA Technical Reports Server (NTRS)

Yang, L. C. (Inventor)

1979-01-01

Apparatus for generating a substantially oscillation-free seismic signal for use in underwater petroleum exploration, including a bag with walls that are flexible but substantially inelastic, and a pressured gas supply for rapidly expanding the bag to its fully expanded condition is described. The inelasticity of the bag permits the application of high pressure gas to rapidly expand it to full size, without requiring a venting mechanism to decrease the pressure as the bag approaches a predetermined size to avoid breaking of the bag.

USGS GeoData Digital Raster Graphics

USGS Publications Warehouse

,

2001-01-01

Passive diffusion samplers have been tested at a number of sites where volatile organic compounds (VOC?s) are the principal contaminants in ground water. Test results generally show good agreement between concentrations of VOC?s in samples collected with diffusion samplers and concentrations in samples collected by purging the water from a well. Diffusion samplers offer several advantages over conventional and low-flow ground-water sampling procedures: ? Elimination of the need to purge a well before collecting a sample and to dispose of contaminated water. ? Elimination of cross-contamination of samples associated with sampling with non-dedicated pumps or sample delivery tubes. ? Reduction in sampling time by as much as 80 percent of that required for ?purge type? sampling methods. ? An increase in the frequency and spatial coverage of monitoring at a site because of the associated savings in time and money. The successful use of diffusion samplers depends on the following three primary factors: (1) understanding site conditions and contaminants of interest (defining sample objectives), (2) validating of results of diffusion samplers against more widely acknowledged sampling methods, and (3) applying diffusion samplers in the field.

Air bag-mediated fatal craniocervical trauma: a case report.

PubMed

Büyük, Yalçin; Uzün, Ibrahim; Erkol, Zerrin; Ağritmiş, Hasan; Ustündağ, Kasim T

2010-07-01

This case report describes a four-year-old girl (102 cm, 17 kg) who sustained fatal craniocerebral injuries as a result of an inflating automobile air bag. The car struck the lid of the sewer system, which was 15 cm above the ground level, at a low speed, and both the driver and passenger air bags inflated. Despite the fact that air bag usage has lessened both the possibility and severity of occupant injuries in frontal collisions, case reports of serious injuries and even deaths especially in children due to air bag deployment, particularly during low speed impacts, highlight the need for changes in both system design and possibly the threshold speed of air bag deployment.

Surface passivation of nano-textured fluorescent SiC by atomic layer deposited TiO2

NASA Astrophysics Data System (ADS)

Lu, Weifang; Ou, Yiyu; Jokubavicius, Valdas; Fadil, Ahmed; Syväjärvi, Mikael; Petersen, Paul Michael; Ou, Haiyan

2016-07-01

Nano-textured surfaces have played a key role in optoelectronic materials to enhance the light extraction efficiency. In this work, morphology and optical properties of nano-textured SiC covered with atomic layer deposited (ALD) TiO2 were investigated. In order to obtain a high quality surface for TiO2 deposition, a three-step cleaning procedure was introduced after RIE etching. The morphology of anatase TiO2 indicates that the nano-textured substrate has a much higher surface nucleated grain density than a flat substrate at the beginning of the deposition process. The corresponding reflectance increases with TiO2 thickness due to increased surface diffuse reflection. The passivation effect of ALD TiO2 thin film on the nano-textured fluorescent 6H-SiC sample was also investigated and a PL intensity improvement of 8.05% was obtained due to the surface passivation.

BAG3 and HIF-1 α coexpression detected by immunohistochemistry correlated with prognosis in hepatocellular carcinoma after liver transplantation.

PubMed

Xiao, Heng; Tong, Rongliang; Cheng, Shaobing; Lv, Zhen; Ding, Chaofeng; Du, Chengli; Xie, Haiyang; Zhou, Lin; Wu, Jian; Zheng, Shusen

2014-01-01

The objective is to determine the effects of BAG3 and HIF-1 α expression on the prognosis of HCC patients after liver transplantation. Samples from 31 patients with HCC receiving liver transplantation were collected for this study. The immunohistochemistry was used to detect the expression of BAG3 and HIF-1 α of HCC samples. According to the immunohistochemistry results, BAG3 and HIF-1 α staining were significantly associated with tumor TNM stage (P = 0.004, P = 0.012). A significant association between high BAG3/HIF-1 α levels and a shorter overall survival was detected, so as the combined BAG3 and HIF-1 α analysis. The results suggested that the expression level of BAG3 and HIF-1 α is efficient prognostic parameters in patients with HCC after liver transplantation.

Role of BAG3 in cancer progression: A therapeutic opportunity.

PubMed

De Marco, Margot; Basile, Anna; Iorio, Vittoria; Festa, Michelina; Falco, Antonia; Ranieri, Bianca; Pascale, Maria; Sala, Gianluca; Remondelli, Paolo; Capunzo, Mario; Firpo, Matthew A; Pezzilli, Raffaele; Marzullo, Liberato; Cavallo, Pierpaolo; De Laurenzi, Vincenzo; Turco, Maria Caterina; Rosati, Alessandra

2018-06-01

BAG3 is a multifunctional protein that can bind to heat shock proteins (Hsp) 70 through its BAG domain and to other partners through its WW domain, proline-rich (PXXP) repeat and IPV (Ile-Pro-Val) motifs. Its intracellular expression can be induced by stressful stimuli, while is constitutive in skeletal muscle, cardiac myocytes and several tumour types. BAG3 can modulate the levels, localisation or activity of its partner proteins, thereby regulating major cell pathways and functions, including apoptosis, autophagy, mechanotransduction, cytoskeleton organisation, motility. A secreted form of BAG3 has been identified in studies on pancreatic ductal adenocarcinoma (PDAC). Secreted BAG3 can bind to a specific receptor, IFITM2, expressed on macrophages, and induce the release of factors that sustain tumour growth and the metastatic process. BAG3 neutralisation therefore appears to constitute a novel potential strategy in the therapy of PDAC and, possibly, other tumours. Copyright © 2017 Elsevier Ltd. All rights reserved.

Short peptides derived from the BAG-1 C-terminus inhibit the interaction between BAG-1 and HSC70 and decrease breast cancer cell growth.

PubMed

Sharp, Adam; Cutress, Ramsey I; Johnson, Peter W M; Packham, Graham; Townsend, Paul A

2009-11-03

BAG-1, a multifunctional protein, interacts with a plethora of cellular targets where the interaction with HSC70 and HSP70, is considered vital. Structural studies have demonstrated the C-terminal of BAG-1 forms a bundle of three alpha-helices of which helices 2 and 3 are directly involved in binding to the chaperones. Here we found peptides derived from helices 2 and 3 of BAG-1 interfered with BAG-1:HSC70 binding. We confirmed that a 12 amino-acid peptide from helix 2 directly interacted with HSC70 and when introduced into MCF-7 and ZR-75-1 cells, these peptides inhibited their growth. In conclusion, we have identified a small domain within BAG-1 which appears to play a critical role in the interaction with HSC70.

Effects of molecular weight on the diffusion coefficient of aquatic dissolved organic matter and humic substances.

PubMed

Balch, J; Guéguen, C

2015-01-01

In situ measurements of labile metal species using diffusive gradients in thin films (DGT) passive samplers are based on the diffusion rates of individual species. Although most studies have dealt with chemically isolated humic substances, the diffusion of dissolved organic matter (DOM) across the hydrogel is not well understood. In this study, the diffusion coefficient (D) and molecular weight (MW) of 11 aquatic DOM and 4 humic substances (HS) were determined. Natural, unaltered aquatic DOM was capable of diffusing across the diffusive gel membrane with D values ranging from 2.48×10(-6) to 5.31×10(-6) cm(2) s(-1). Humic substances had diffusion coefficient values ranging from 3.48×10(-6) to 6.05×10(-6) cm(2) s(-1), congruent with previous studies. Molecular weight of aquatic DOM and HS samples (∼500-1750 Da) measured using asymmetrical flow field-flow fractionation (AF4) strongly influenced D, with larger molecular weight DOM having lower D values. No noticeable changes in DOM size properties were observed during the diffusion process, suggesting that DOM remains intact following diffusion across the diffusive gel. The influence of molecular weight on DOM mobility will assist in further understanding and development of the DGT technique and the uptake and mobility of contaminants associated with DOM in aquatic environments. Copyright © 2014 Elsevier Ltd. All rights reserved.

75 FR 36679 - Polyethylene Retail Carrier Bags From China, Malaysia, and Thailand; Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-28

... Carrier Bags From China, Malaysia, and Thailand; Determinations On the basis of the record \\1\\ developed... antidumping duty orders on polyethylene retail carrier bags from China, Malaysia, and Thailand would be likely... Retail Carrier Bags from China, Malaysia, and Thailand: Investigation Nos. 731-TA-1043-1045 (Review). By...

75 FR 36359 - Polyethylene Retail Carrier Bags From Thailand: Extension of Time Limit for Preliminary Results...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-25

... Bags From Thailand: Extension of Time Limit for Preliminary Results of Antidumping Duty Administrative... polyethylene retail carrier bags from Thailand. See Antidumping Duty Order: Polyethylene Retail Carrier Bags From Thailand, 69 FR 48204 (August 9, 2004). On September 22, 2009, we published a notice of initiation...

75 FR 75454 - Polyethylene Retail Carrier Bags From Thailand: Extension of Time Limit for the Final Results of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-03

... Bags From Thailand: Extension of Time Limit for the Final Results of the Antidumping Duty... preliminary results of review of the antidumping duty order on polyethylene retail carrier bags from Thailand. See Polyethylene Retail Carrier Bags From Thailand: Preliminary Results of Antidumping Duty...

75 FR 23673 - Polyethylene Retail Carrier Bags from Thailand: Extension of Time Limit for Preliminary Results...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-04

... Bags from Thailand: Extension of Time Limit for Preliminary Results of Antidumping Duty Administrative... Thailand. See Antidumping Duty Order: Polyethylene Retail Carrier Bags From Thailand, 69 FR 48204 (August 9... Co., Ltd., Landblue (Thailand) Co., Ltd., Sahachit Watana Plastics Ind. Co., Ltd., Thai Plastic Bags...

49 CFR 178.519 - Standards for plastic film bags.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Standards for plastic film bags. 178.519 Section... PACKAGINGS Non-bulk Performance-Oriented Packaging Standards § 178.519 Standards for plastic film bags. (a) The identification code for a plastic film bag is 5H4. (b) Construction requirements for plastic film...

40 CFR 63.10899 - What are my recordkeeping and reporting requirements?

Code of Federal Regulations, 2011 CFR

2011-07-01

... of each inspection, and the results of any maintenance performed on the bag filters. (ii) The date... applicable, you must keep records for bag leak detection systems as follows: (i) Records of the bag leak detection system output; (ii) Records of bag leak detection system adjustments, including the date and time...

75 FR 16431 - Polyethylene Retail Carrier Bags From Indonesia: Final Determination of Sales at Less Than Fair...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-01

... Bags From Indonesia: Final Determination of Sales at Less Than Fair Value AGENCY: Import Administration...) has determined that imports of polyethylene retail carrier bags (PRCBs) from Indonesia are being, or... Retail Carrier Bags from Indonesia: Preliminary Determination of Sales at Less Than Fair Value and...

49 CFR 178.518 - Standards for woven plastic bags.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Standards for woven plastic bags. 178.518 Section... PACKAGINGS Non-bulk Performance-Oriented Packaging Standards § 178.518 Standards for woven plastic bags. (a) The following are identification codes for woven plastic bags: (1) 5H1 for an unlined or non-coated...

49 CFR 178.518 - Standards for woven plastic bags.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Standards for woven plastic bags. 178.518 Section...-bulk Performance-Oriented Packaging Standards § 178.518 Standards for woven plastic bags. (a) The following are identification codes for woven plastic bags: (1) 5H1 for an unlined or non-coated woven...

49 CFR 178.518 - Standards for woven plastic bags.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Standards for woven plastic bags. 178.518 Section...-bulk Performance-Oriented Packaging Standards § 178.518 Standards for woven plastic bags. (a) The following are identification codes for woven plastic bags: (1) 5H1 for an unlined or non-coated woven...

49 CFR 178.518 - Standards for woven plastic bags.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Standards for woven plastic bags. 178.518 Section...-bulk Performance-Oriented Packaging Standards § 178.518 Standards for woven plastic bags. (a) The following are identification codes for woven plastic bags: (1) 5H1 for an unlined or non-coated woven...

75 FR 30900 - Fisker Automotive; Receipt of Application for Temporary Exemption From Advanced Air Bag...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-02

...-0069] Fisker Automotive; Receipt of Application for Temporary Exemption From Advanced Air Bag... temporary exemption from certain advanced air bag requirements of FMVSS No. 208. The basis for the... air bag requirements. Fisker has requested an exemption for the Karma model, and that the exemption...

50 CFR 622.456 - Bag limits.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., DEPARTMENT OF COMMERCE FISHERIES OF THE CARIBBEAN, GULF OF MEXICO, AND SOUTH ATLANTIC Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands § 622.456 Bag limits. (a) Applicability. Section 622.11(a... fishing license issued by Puerto Rico or the U.S. Virgin Islands. (b) Bag limit. The bag limit for spiny...