14 CFR 399.91 - Air carrier participation in programs of technical assistance to airlines of less developed...

Code of Federal Regulations, 2011 CFR

2011-01-01

... § 399.91 Air carrier participation in programs of technical assistance to airlines of less developed... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Air carrier participation in programs of technical assistance to airlines of less developed countries. 399.91 Section 399.91 Aeronautics and Space...

14 CFR 399.91 - Air carrier participation in programs of technical assistance to airlines of less developed...

Code of Federal Regulations, 2010 CFR

2010-01-01

... § 399.91 Air carrier participation in programs of technical assistance to airlines of less developed... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Air carrier participation in programs of technical assistance to airlines of less developed countries. 399.91 Section 399.91 Aeronautics and Space...

Dynamically allocated virtual clustering management system

NASA Astrophysics Data System (ADS)

Marcus, Kelvin; Cannata, Jess

2013-05-01

The U.S Army Research Laboratory (ARL) has built a "Wireless Emulation Lab" to support research in wireless mobile networks. In our current experimentation environment, our researchers need the capability to run clusters of heterogeneous nodes to model emulated wireless tactical networks where each node could contain a different operating system, application set, and physical hardware. To complicate matters, most experiments require the researcher to have root privileges. Our previous solution of using a single shared cluster of statically deployed virtual machines did not sufficiently separate each user's experiment due to undesirable network crosstalk, thus only one experiment could be run at a time. In addition, the cluster did not make efficient use of our servers and physical networks. To address these concerns, we created the Dynamically Allocated Virtual Clustering management system (DAVC). This system leverages existing open-source software to create private clusters of nodes that are either virtual or physical machines. These clusters can be utilized for software development, experimentation, and integration with existing hardware and software. The system uses the Grid Engine job scheduler to efficiently allocate virtual machines to idle systems and networks. The system deploys stateless nodes via network booting. The system uses 802.1Q Virtual LANs (VLANs) to prevent experimentation crosstalk and to allow for complex, private networks eliminating the need to map each virtual machine to a specific switch port. The system monitors the health of the clusters and the underlying physical servers and it maintains cluster usage statistics for historical trends. Users can start private clusters of heterogeneous nodes with root privileges for the duration of the experiment. Users also control when to shutdown their clusters.

Personality traits in Huntington's disease: An exploratory study of gene expansion carriers and non-carriers.

PubMed

Larsen, Ida Unmack; Mortensen, Erik Lykke; Vinther-Jensen, Tua; Nielsen, Jørgen Erik; Knudsen, Gitte Moos; Vogel, Asmus

2016-12-01

Huntington's disease (HD) is associated with risk for developing psychiatric symptoms. Vulnerability or resilience to psychiatric symptoms may be associated with personality traits. This exploratory study, aimed to investigate personality traits in a large cohort of HD carriers and at risk gene-expansion negative individuals (HD non-carriers), exploring whether carrying the HD gene or growing up in an HD family influences personality traits. Forty-seven HD carriers, Thirty-nine HD non-carriers, and 121 healthy controls answered the Danish version of the revised NEO personality inventory. Comparisons between HD carriers and HD non-carriers were mostly non-significant but the combined group of HD carriers and non-carriers showed significantly higher scores on the facets: "hostility," "assertiveness," and "activity" and on the trait "Conscientiousness" relative to controls, "Conscientiousness" have been associated with resilience to psychiatric symptoms. Twelve HD carriers and non-carriers were classified as depressed and showed significantly lower scores on "Extraversion" and "Conscientiousness" and significantly higher scores on "Neuroticism," which are associated with vulnerability to psychiatric symptoms. Our findings suggest that, there is no direct effect of the HD gene on personality traits, but that personality assessment may be relevant to use when identifying individuals from HD families who are vulnerable to develop psychiatric symptoms. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

ALICE HLT Cluster operation during ALICE Run 2

NASA Astrophysics Data System (ADS)

Lehrbach, J.; Krzewicki, M.; Rohr, D.; Engel, H.; Gomez Ramirez, A.; Lindenstruth, V.; Berzano, D.; ALICE Collaboration

2017-10-01

ALICE (A Large Ion Collider Experiment) is one of the four major detectors located at the LHC at CERN, focusing on the study of heavy-ion collisions. The ALICE High Level Trigger (HLT) is a compute cluster which reconstructs the events and compresses the data in real-time. The data compression by the HLT is a vital part of data taking especially during the heavy-ion runs in order to be able to store the data which implies that reliability of the whole cluster is an important matter. To guarantee a consistent state among all compute nodes of the HLT cluster we have automatized the operation as much as possible. For automatic deployment of the nodes we use Foreman with locally mirrored repositories and for configuration management of the nodes we use Puppet. Important parameters like temperatures, network traffic, CPU load etc. of the nodes are monitored with Zabbix. During periods without beam the HLT cluster is used for tests and as one of the WLCG Grid sites to compute offline jobs in order to maximize the usage of our cluster. To prevent interference with normal HLT operations we separate the virtual machines running the Grid jobs from the normal HLT operation via virtual networks (VLANs). In this paper we give an overview of the ALICE HLT operation in 2016.

76 FR 77716 - Alternate Passenger Rail Service Pilot Program

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-14

... program that permits a rail carrier or rail carriers that own infrastructure over which Amtrak operates... develops a pilot program that permits a rail carrier or rail carriers that own infrastructure over which... the infrastructure as described in Sec. 269.7 of this final rule. In addition, such information...

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...

Chemical Looping Combustion Reactions and Systems

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

Sarofim, Adel; Lighty, JoAnn; Smith, Philip

2014-03-01

Chemical Looping Combustion (CLC) is one promising fuel-combustion technology, which can facilitate economic CO{sub 2} capture in coal-fired power plants. It employs the oxidation/reduction characteristics of a metal, or oxygen carrier, and its oxide, the oxidizing gas (typically air) and the fuel source may be kept separate. This topical report discusses the results of four complementary efforts: (5.1) the development of process and economic models to optimize important design considerations, such as oxygen carrier circulation rate, temperature, residence time; (5.2) the development of high-performance simulation capabilities for fluidized beds and the collection, parameter identification, and preliminary verification/uncertainty quantification; (5.3) themore » exploration of operating characteristics in the laboratoryscale bubbling bed reactor, with a focus on the oxygen carrier performance, including reactivity, oxygen carrying capacity, attrition resistance, resistance to deactivation, cost and availability; and (5.4) the identification of kinetic data for copper-based oxygen carriers as well as the development and analysis of supported copper oxygen carrier material. Subtask 5.1 focused on the development of kinetic expressions for the Chemical Looping with Oxygen Uncoupling (CLOU) process and validating them with reported literature data. The kinetic expressions were incorporated into a process model for determination of reactor size and oxygen carrier circulation for the CLOU process using ASPEN PLUS. An ASPEN PLUS process model was also developed using literature data for the CLC process employing an iron-based oxygen carrier, and the results of the process model have been utilized to perform a relative economic comparison. In Subtask 5.2, the investigators studied the trade-off between modeling approaches and available simulations tools. They quantified uncertainty in the high-performance computing (HPC) simulation tools for CLC bed applications. Furthermore, they performed a sensitivity analysis for velocity, height and polydispersity and compared results against literature data for experimental studies of CLC beds with no reaction. Finally, they present an optimization space using simple non-reactive configurations. In Subtask 5.3, through a series of experimental studies, behavior of a variety of oxygen carriers with different loadings and manufacturing techniques was evaluated under both oxidizing and reducing conditions. The influences of temperature, degree of carrier conversion and thermodynamic driving force resulting from the difference between equilibrium and system O{sub 2} partial pressures were evaluated through several experimental campaigns, and generalized models accounting for these influences were developed to describe oxidation and oxygen release. Conversion of three solid fuels with widely ranging reactivities was studied in a small fluidized bed system, and all but the least reactive fuel (petcoke) were rapidly converted by oxygen liberated from the CLOU carrier. Attrition propensity of a variety of carriers was also studied, and the carriers produced by freeze granulation or impregnation of preformed substrates displayed the lowest rates of attrition. Subtask 5.4 focused on gathering kinetic data for a copper-based oxygen carrier to assist with modeling of a functioning chemical looping reactor. The kinetics team was also responsible for the development and analysis of supported copper oxygen carrier material.« less

Borehole model for simulation transport geothermal heat with heat pipe system and with forced circulation of heat carrier

NASA Astrophysics Data System (ADS)

Jakubský, Michal; Lenhard, Richard; Vantúch, Martin; Malcho, Milan

2012-04-01

In the call OPVaV-2008/2.2/01-SORO Operational Programme Research and Development - knowledge and technology transfer from research and development into practice (ITMS-26220220057), whose strategic goal is "Device to use low-potential geothermal heat without forced circulation of heat carrier deep in the well "in the Department of Energy laboratory techniques to construct a simulator of transport low potential of geothermal energy in comparative test-drilling in the laboratory. The article describes a device that was designed as a scale model of two deep boreholes each of which withdraws the earth's heat by heat transfer technology and heat carrier. Device using forced circulation of heat carrier will respond in the construction of equipment currently used to transport heat from deep borehole. As the heat carrier will be used CO2. Facilities without using forced circulation of heat carrier, the new technology, which will be used as heat carrier ammonia (NH3).

A recovery principle provides insight into auxin pattern control in the Arabidopsis root

PubMed Central

Moore, Simon; Liu, Junli; Zhang, Xiaoxian; Lindsey, Keith

2017-01-01

Regulated auxin patterning provides a key mechanism for controlling root growth and development. We have developed a data-driven mechanistic model using realistic root geometry and formulated a principle to theoretically investigate quantitative auxin pattern recovery following auxin transport perturbation. This principle reveals that auxin patterning is potentially controlled by multiple combinations of interlinked levels and localisation of influx and efflux carriers. We demonstrate that (1) when efflux carriers maintain polarity but change levels, maintaining the same auxin pattern requires non-uniform and polar distribution of influx carriers; (2) the emergence of the same auxin pattern, from different levels of influx carriers with the same nonpolar localisation, requires simultaneous modulation of efflux carrier level and polarity; and (3) multiple patterns of influx and efflux carriers for maintaining an auxin pattern do not have spatially proportional correlation. This reveals that auxin pattern formation requires coordination between influx and efflux carriers. We further show that the model makes various predictions that can be experimentally validated. PMID:28220889

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.

Air carrier operations system model

DOT National Transportation Integrated Search

2001-03-01

Representatives from the Federal Aviation Administration (FAA) and several 14 Code of Federal Regulations (CFR) Part 121 air carriers met several times during 1999-2000 to develop a system engineering model of the generic functions of air carrier ope...

The risk for developing cancer in Israeli ATM, BLM, and FANCC heterozygous mutation carriers.

PubMed

Laitman, Yael; Boker-Keinan, Lital; Berkenstadt, Michal; Liphsitz, Irena; Weissglas-Volkov, Daphna; Ries-Levavi, Liat; Sarouk, Ifat; Pras, Elon; Friedman, Eitan

2016-03-01

Cancer risks in heterozygous mutation carriers of the ATM, BLM, and FANCC genes are controversial. To shed light on this issue, cancer rates were evaluated by cross referencing asymptomatic Israeli heterozygous mutation carriers in the ATM, BLM, and FANCC genes with cancer diagnoses registered at the Israeli National Cancer Registry (INCR). Comparison of observed to expected Standardized Incidence Rates (SIR) was performed. Overall, 474 individuals participated in the study: 378 females; 25 Arab and 31 Jewish ATM carriers, 152 BLM carriers, and 170 FANCC carriers (all Ashkenazim). Age range at genotyping was 19-53 years (mean + SD 30.6 + 5 years). In addition, 96 males were included; 5, 34, and 57 ATM, BLM, and FANCC mutation carriers, respectively. Over 5-16 years from genotyping (4721 person/years), 15 new cancers were diagnosed in mutation carriers: 5 breast, 4 cervical, 3 melanomas, and one each bone sarcoma, pancreatic, and colorectal cancer. No single cancer diagnosis was more prevalent then expected in all groups combined or per gene analyzed. Specifically breast cancer SIR was 0.02-0.77. We conclude that Israeli ATM, BLM, and FANCC heterozygous mutation carriers are not at an increased risk for developing cancer. Copyright © 2015 Elsevier Inc. All rights reserved.

Unpressurized Logistics Carriers for the International Space Station: Lessons Learned

NASA Technical Reports Server (NTRS)

Robbins, William W., Jr.

1999-01-01

The International Space Station has been in development since 1984, and has recently begun on orbit assembly. Most of the hardware for the Space Station has been manufactured and the rest is well along in design. The major sets of hardware that are still to be developed for Space Station are the pallets and interfacing hardware for resupply of unpressurized spares and scientific payloads. Over the last ten years, there have been numerous starts, stops, difficulties and challenges encountered in this effort. The Space Station program is now entering the beginning of orbital operations. The Program is only now addressing plans to design and build the carriers that will be needed to carry the unpressurized cargo for the Space Station lifetime. Unpressurized carrier development has been stalled due to a broad range of problems that occurred over the years. These problems were not in any single area, but encompassed budgetary, programmatic, and technical difficulties. Some lessons of hindsight can be applied to developing carriers for the Space Station. Space Station teams are now attempting to incorporate the knowledge gained into the current development efforts for external carriers. In some cases, the impacts of these lessons are unrecoverable for Space Station, but can and should be applied to future programs. This paper examines the progress and problems to date with unpressurized carrier development identifies the lessons to be learned, and charts the course for finally accomplishing the delivery of these critical hardware sets.

Nano-lipoidal carriers of tretinoin with enhanced percutaneous absorption, photostability, biocompatibility and anti-psoriatic activity.

PubMed

Raza, Kaisar; Singh, Bhupinder; Lohan, Shikha; Sharma, Gajanand; Negi, Poonam; Yachha, Yukhti; Katare, Om Prakash

2013-11-01

Tretinoin (TRE) is a widely used retinoid for the topical treatment of acne, psoriasis, skin cancer and photoaging. Despite unmatchable efficacy, it is associated with several vexatious side effects like marked skin erythema, peeling and irritation, eventually leading to poor patient compliance. Its photo-instability and high lipophilicity also pose challenges in the development of a suitable topical product. The present study, therefore, aims to develop biocompatible lipid-based nanocarriers of TRE to improve its skin delivery, photostability, biocompatibility and pharmacodynamic efficacy. The TRE-loaded liposomes, ethosomes, solid lipid nanoparticles (SLNs) and nanostructured lipidic carriers (NLCs) were prepared and characterized for micromeritics, surface charge, percent drug efficiency and morphology. Bioadhesive hydrogels of the developed systems were also evaluated for rheological characterization, photostability, ex vivo skin permeation and retention employing porcine skin, and anti-psoriatic activity in mouse tail model. Nanoparticulate carriers (SLNs, NLCs) offered enhanced photostability, skin transport and anti-psoriatic activity vis-à-vis the vesicular carriers (liposomes, ethosomes) and the marketed product. However, all the developed nanocarriers were found to be more biocompatible and effective than the marketed product. These encouraging findings can guide in proper selection of topical carriers among diversity of such available carriers systems. Copyright © 2013 Elsevier B.V. All rights reserved.

Hitchhiker: Customer Accommodations and Requirements Specifications (CARS)

NASA Technical Reports Server (NTRS)

1992-01-01

In 1984, NASA Headquarters established projects at the Goddard Space Flight Center (GSFC) and the Marshall Space Flight Center (MSFC) to develop quick-reaction carrier systems for low-cost 'flight of opportunity' or secondary payloads on the Space Transportation System (STS). One of these projects is the Hitchhiker (HH) Program. GSFC has developed a family of carrier equipment known as the Shuttle Payload of Opportunity Carrier (SPOC) system for mounting small payloads such as HH to the side of the Orbiter payload bay. The side-mounted HHs are referred to as Hitchhiker-G (HH-G). MSFC developed a cross-bay 'bridge-type' carrier structure called the Hitchhiker-M (HH-M). In 1987, responsibility for the HH-M carrier was transferred to and is now managed by the HH Project Office at the GSFC. The HH-M carrier now uses the same interchangeable SPOC avionics unit and the same electrical interfaces and services developed for HH-G. National Aeronautics and Space Administration (NASA) has created this document to acquaint potential HH system customers with the facilities NASA provides and the requirements which customers must satisfy to use these facilities. This publication defines interface items required for integrating customer equipment with the HH carrier system. Those items such as mounting equipment and electrical inputs and outputs; configuration, environmental, command, telemetry, and operational constraints are described as well as weight, power, and communications. The purpose of this publication is to help the customer understand essential integration documentation requirements and to prepare a Customer Payload Requirements (CPR) document.

FMCSA safety program effectiveness measurement : Carrier Intervention Effectiveness Model, Version 1.1, technical report.

DOT National Transportation Integrated Search

2017-04-01

The Federal Motor Carrier Safety Administration (FMCSA), in cooperation with the John A. Volpe National Transportation Systems Center (Volpe), has developed a quantitative model to measure the effectiveness of motor carrier interventions in terms of ...

Effectiveness of screening hospital admissions to detect asymptomatic carriers of Clostridium difficile: a modeling evaluation.

PubMed

Lanzas, Cristina; Dubberke, Erik R

2014-08-01

Both asymptomatic and symptomatic Clostridium difficile carriers contribute to new colonizations and infections within a hospital, but current control strategies focus only on preventing transmission from symptomatic carriers. Our objective was to evaluate the potential effectiveness of methods targeting asymptomatic carriers to control C. difficile colonization and infection (CDI) rates in a hospital ward: screening patients at admission to detect asymptomatic C. difficile carriers and placing positive patients into contact precautions. We developed an agent-based transmission model for C. difficile that incorporates screening and contact precautions for asymptomatic carriers in a hospital ward. We simulated scenarios that vary according to screening test characteristics, colonization prevalence, and type of strain present at admission. In our baseline scenario, on average, 42% of CDI cases were community-onset cases. Within the hospital-onset (HO) cases, approximately half were patients admitted as asymptomatic carriers who became symptomatic in the ward. On average, testing for asymptomatic carriers reduced the number of new colonizations and HO-CDI cases by 40%-50% and 10%-25%, respectively, compared with the baseline scenario. Test sensitivity, turnaround time, colonization prevalence at admission, and strain type had significant effects on testing efficacy. Testing for asymptomatic carriers at admission may reduce both the number of new colonizations and HO-CDI cases. Additional reductions could be achieved by preventing disease in patients who are admitted as asymptomatic carriers and developed CDI during the hospital stay.

Recent Progress in Functional Micellar Carriers with Intrinsic Therapeutic Activities for Anticancer Drug Delivery.

PubMed

Qu, Ying; Chu, BingYang; Shi, Kun; Peng, JinRong; Qian, ZhiYong

2017-12-01

Polymeric micelles have presented superior delivery properties for poorly water-soluble chemotherapeutic agents. However, it remains discouraging that there may be some additional short or long-term toxicities caused by the metabolites of high quantities of carriers. If carriers had simultaneous therapeutic effects with the drug, these issues would not be a concern. For this, carriers not only simply act as drug carriers, but also exert an intrinsic therapeutic effect as a therapeutic agent. The functional micellar carriers would be beneficial to maximize the anticancer effect, overcome the drug resistance and reduce the systemic toxicity. In this review, we aim to summarize the recent progress on the development of functional micellar carriers with intrinsic anticancer activities for the delivery of anticancer drugs. This review focuses on the design strategies, properties of carriers and the drug loading behavior. In addition, the combinational therapeutic effects between carriers and chemotherapeutic agents are also discussed.

Development auxiliaries for dyeing polyester with disperse dyes at low temperatures

NASA Astrophysics Data System (ADS)

Carrion-Fite, F. J.; Radei, S.

2017-10-01

High-molecular weight organic compounds known as carriers are widely used to expedite polyester dyeing at atmospheric pressure at 100 °C. However, carriers are usually poorly biodegradable and can partially plasticize fibres. Also, dyeing at temperatures above 100 °C in the absence of a carrier entails using expensive equipment. In this work, we developed an alternative method for dyeing polyester at temperatures below 100 °C that reduces energy expenses, dispenses with the need to invest in new equipment and avoids the undesirable effects of non-biodegradable carriers. The method uses disperse dyes in a microemulsion containing a low proportion of a non-toxic organic solvent and either of two alternative development auxiliaries (coumarin and o-vanillin) that is prepared with the aid of ultrasound.

Long-lived hot-carrier light emission and large blue shift in formamidinium tin triiodide perovskites.

PubMed

Fang, Hong-Hua; Adjokatse, Sampson; Shao, Shuyan; Even, Jacky; Loi, Maria Antonietta

2018-01-16

A long-lived hot carrier population is critical in order to develop working hot carrier photovoltaic devices with efficiencies exceeding the Shockley-Queisser limit. Here, we report photoluminescence from hot-carriers with unexpectedly long lifetime (a few ns) in formamidinium tin triiodide. An unusual large blue shift of the time-integrated photoluminescence with increasing excitation power (150 meV at 24 K and 75 meV at 293 K) is displayed. On the basis of the analysis of energy-resolved and time-resolved photoluminescence, we posit that these phenomena are associated with slow hot carrier relaxation and state-filling of band edge states. These observations are both important for our understanding of lead-free hybrid perovskites and for an eventual future development of efficient lead-free perovskite photovoltaics.

Development of a shuttle recovery Commercial Materials Processing in Space (CMPS) program

NASA Technical Reports Server (NTRS)

1989-01-01

The work performed has covered the following tasks: update commercial users requirements; assess availability of carriers and facilities; shuttle availability assessment; development of optimum accommodations plan; and payload documentation requirements assessment. The results from the first four tasks are presented. To update commercial user requirements, contacts were made with the JEA and CCDS partners to obtain copies of their most recent official flight requests. From these requests the commercial partners' short and long range plans for flight dates, flight frequency, experiment hardware and carriers was determined. A 34 by 44 inch chart was completed to give a snapshot view of the progress of commercialization in space. Further, an assessment was made of the availability of carriers and facilities. Both existing carriers and those under development were identified for use by the commercial partners. A data base was compiled to show the capabilities of the carriers. A shuttle availability assessment was performed using the primary and secondary shuttle manifests released by NASA. Analysis of the manifest produced a flight-by-flight list of flight opportunities available to commercial users. Using inputs from the first three tasks, an Optimum Accommodations Plan was developed. The Accommodation Plan shows the commercial users manifested by flight, the experiment flown, the carrier used and complete list of commercial users that could not be manifested in each calendar year.

FMCSA safety program effectiveness measurement : carrier intervention effectiveness model (CIEM), version 1.1, report for Fiscal Year 2012 interventions.

DOT National Transportation Integrated Search

2016-11-01

The Federal Motor Carrier Safety Administration (FMCSA), in cooperation with the John A. Volpe National Transportation Systems Center (Volpe), has developed a quantitative model to measure the effectiveness of motor carrier interventions in terms of ...

FMCSA Safety Program Effectiveness Measurement: Carrier Intervention Effectiveness Model (CIEM), Version 1.1 Report for Fiscal Year 2014 Interventions

DOT National Transportation Integrated Search

2018-04-01

The Federal Motor Carrier Safety Administration (FMCSA), in cooperation with the John A. Volpe National Transportation Systems Center (Volpe), has developed a quantitative model to measure the effectiveness of motor carrier interventions in terms of ...

FMCSA safety program effectiveness measurement: carrier intervention effectiveness model (CIEM), version 1.1 : report for fiscal year 2013 interventions.

DOT National Transportation Integrated Search

2017-04-01

The Federal Motor Carrier Safety Administration (FMCSA), in cooperation with the John A. Volpe National Transportation Systems Center (Volpe), has developed a quantitative model to measure the effectiveness of motor carrier interventions in terms of ...

FMCSA safety program effectiveness measurement : carrier intervention effectiveness model, version 1.0, summary report for fiscal years 2009, 2010, 2011.

DOT National Transportation Integrated Search

2015-01-01

The Federal Motor Carrier Safety Administration (FMCSA), in cooperation with the John A. Volpe National : Transportation Systems Center (Volpe), has developed a quantitative model to measure the effectiveness of motor : carrier interventions in terms...

FMCSA safety program effectiveness measurement : Carrier Intervention Effectiveness Model (CIEM), Version 1.1, report for fiscal year 2013 interventions.

DOT National Transportation Integrated Search

2017-04-01

The Federal Motor Carrier Safety Administration (FMCSA), in cooperation with the John A. Volpe National Transportation Systems Center (Volpe), has developed a quantitative model to measure the effectiveness of motor carrier interventions in terms of ...

Federal motor carrier safety administration safety 2010 strategy and performance planning : project description

DOT National Transportation Integrated Search

2000-12-01

The Motor Carrier Safety Improvement Act (MCSIA) of 1999, Pub. L. 106-159, created the Federal Motor Carrier Safety Administration (FMCSA) in January 2000. Section 104 of the Act requires the Secretary to develop a long-term strategy for improving co...

75 FR 60493 - Advisory Circular 120-79A, Developing and Implementing an Air Carrier Continuing Analysis and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-30

... and Implementing an Air Carrier Continuing Analysis and Surveillance System AGENCY: Federal Aviation... Analysis and Surveillance System''. This new advisory circular (AC) updates AC 120-79 originally issued on... Analysis and Surveillance System (CASS) required for commercial operators and air carriers certificated...

Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS)

ERIC Educational Resources Information Center

Hagerman, Paul J.; Hagerman, Randi J.

2004-01-01

Carriers of fragile X mental retardation 1 ("FMR1") premutation alleles (55 to 200 CGG repeats) are generally spared the more serious neurodevelopmental problems associated with the full-mutation carriers (greater than 200 repeats) of fragile X syndrome. However, some adult male premutation carriers (55-200 repeats) develop a neurological syndrome…

Biomacromolecules as carriers in drug delivery and tissue engineering.

PubMed

Zhang, Yujie; Sun, Tao; Jiang, Chen

2018-01-01

Natural biomacromolecules have attracted increased attention as carriers in biomedicine in recent years because of their inherent biochemical and biophysical properties including renewability, nontoxicity, biocompatibility, biodegradability, long blood circulation time and targeting ability. Recent advances in our understanding of the biological functions of natural-origin biomacromolecules and the progress in the study of biological drug carriers indicate that such carriers may have advantages over synthetic material-based carriers in terms of half-life, stability, safety and ease of manufacture. In this review, we give a brief introduction to the biochemical properties of the widely used biomacromolecule-based carriers such as albumin, lipoproteins and polysaccharides. Then examples from the clinic and in recent laboratory development are summarized. Finally the current challenges and future prospects of present biological carriers are discussed.

Polyethylene Based Materials for Biofilm Carriers Used in Wastewater Treatment

NASA Astrophysics Data System (ADS)

Moga, I. C.; Iordache, O. I.; Petrescu, G.; Pricop, F.; Dumitrescu, I.

2018-06-01

The moving bed biofilm technology is based on biofilm carriers on which consortia of microorganisms attach, develop and grow. Around the world are known many biofilm carrier variants made of varied materials. The most common materials are based on polyethylene since this material has a close to water density. The authors propose a novel biofilm carrier to be used in tertiary treatment for tannery and paper-mill wastewaters. The biological treatment is based on fungal activity. The selected fungal strains will be grown on innovative polyethylene carriers containing cellulose. The carrier will be designed to be exploited in a moving bed bioreactor and to favour fungal growth in the presence of competing bacteria.

LWS/SET Technology Experiment Carrier

NASA Technical Reports Server (NTRS)

Sherman, Barry; Giffin, Geoff

2002-01-01

This paper examines the approach taken to building a low-cost, modular spacecraft bus that can be used to support a variety of technology experiments in different space environments. It describes the techniques used and design drivers considered to ensure experiment independence from as yet selected host spacecraft. It describes the technology experiment carriers that will support NASA's Living With a Star Space Environment Testbed space missions. NASA has initiated the Living With a Star (LWS) Program to develop a better scientific understanding to address the aspects of the connected Sun-Earth system that affect life and society. A principal goal of the program is to bridge the gap between science, engineering, and user application communities. The Space Environment Testbed (SET) Project is one element of LWS. The Project will enable future science, operational, and commercial objectives in space and atmospheric environments by improving engineering approaches to the accommodation and/or mitigation of the effects of solar variability on technological systems. The SET Project is highly budget constrained and must seek to take advantage of as yet undetermined partnering opportunities for access to space. SET will conduct technology validation experiments hosted on available flight opportunities. The SET Testbeds will be developed in a manner that minimizes the requirements for accommodation, and will be flown as flight opportunities become available. To access the widest range of flight opportunities, two key development requirements are to maintain flexibility with respect to accommodation constraints and to have the capability to respond quickly to flight opportunities. Experiments, already developed to the technology readiness level of needing flight validation in the variable Sun-Earth environment, will be selected on the basis of the need for the subject technology, readiness for flight, need for flight resources and particular orbit. Experiments will be accumulated by the Project and manifested for specific flight opportunities as they become available. The SET Carrier is designed to present a standard set of interfaces to SET technology experiments and to be modular and flexible enough to interface to a variety of possible host spacecraft. The Carrier will have core components and mission unique components. Once the core carrier elements have been developed, only the mission unique components need to be defined and developed for any particular mission. This approach will minimize the mission specific cost and development schedule for a given flight opportunity. The standard set of interfaces provided by SET to experiments allows them to be developed independent of the particulars of a host spacecraft. The Carrier will provide the power, communication, and the necessary monitoring features to operate experiments. The Carrier will also provide all of the mechanical assemblies and harnesses required to adapt experiments to a particular host. Experiments may be hosted locally with the Carrier or remotely on the host spacecraft. The Carrier design will allow a single Carrier to support a variable number of experiments and will include features that support the ability to incrementally add experiments without disturbing the core architecture.

Chemical-Looping Combustion and Gasification of Coals and Oxygen Carrier Development: A Brief Review

DOE PAGES

Wang, Ping; Means, Nicholas; Shekhawat, Dushyant; ...

2015-09-24

Chemical-looping technology is one of the promising CO 2 capture technologies. It generates a CO 2 enriched flue gas, which will greatly benefit CO 2 capture, utilization or sequestration. Both chemical-looping combustion (CLC) and chemical-looping gasification (CLG) have the potential to be used to generate power, chemicals, and liquid fuels. Chemical-looping is an oxygen transporting process using oxygen carriers. Recently, attention has focused on solid fuels such as coal. Coal chemical-looping reactions are more complicated than gaseous fuels due to coal properties (like mineral matter) and the complex reaction pathways involving solid fuels. The mineral matter/ash and sulfur in coalmore » may affect the activity of oxygen carriers. Oxygen carriers are the key issue in chemical-looping processes. Thermogravimetric analysis (TGA) has been widely used for the development of oxygen carriers (e.g., oxide reactivity). Two proposed processes for the CLC of solid fuels are in-situ Gasification Chemical-Looping Combustion (iG-CLC) and Chemical-Looping with Oxygen Uncoupling (CLOU). The objectives of this review are to discuss various chemical-looping processes with coal, summarize TGA applications in oxygen carrier development, and outline the major challenges associated with coal chemical-looping in iG-CLC and CLOU.« less

A Two-Phase Approach to Developing SNAP: an iPhone Application to Support Appointment Scheduling and Management for Women with a BRCA Mutation.

PubMed

Scherr, Courtney Lynam; Feuston, Jessica L; Nixon, Dawn M; Cohen, Stephanie A

2018-04-01

Professional organizations provide surveillance guidelines for BRCA1 and BRCA2 (BRCA) carriers with intact breasts and/or ovaries to facilitate early cancer detection. However, literature indicates adherence to surveillance guidelines is inconsistent at best. Using the Messaging Model for Health Communication Campaigns framework, we undertook a two-phase formative research approach to develop an intervention to promote adherence to surveillance guidelines. Discussion groups identified preferred intervention format and function in phase I. Findings indicated carriers desired a phone application (app) to assist with surveillance management and appointment tracking. Thus, an iPhone app for carriers to track appointments based on published surveillance guidelines was developed. In phase II, we obtained feedback from BRCA carriers via a survey during a prototype demonstration at a regional conference. Participants in phase II wanted reminder capabilities and the ability to add and modify information fields. This feedback informed intervention modifications, resulting in the Scheduling Necessary Advised Procedures (SNAP) iPhone app currently being pilot tested by BRCA carriers throughout the USA.

Mission Engineering of a Rapid Cycle Spacecraft Logistics Fleet

NASA Technical Reports Server (NTRS)

Holladay, Jon; McClendon, Randy (Technical Monitor)

2002-01-01

The requirement for logistics re-supply of the International Space Station has provided a unique opportunity for engineering the implementation of NASA's first dedicated pressurized logistics carrier fleet. The NASA fleet is comprised of three Multi-Purpose Logistics Modules (MPLM) provided to NASA by the Italian Space Agency in return for operations time aboard the International Space Station. Marshall Space Flight Center was responsible for oversight of the hardware development from preliminary design through acceptance of the third flight unit, and currently manages the flight hardware sustaining engineering and mission engineering activities. The actual MPLM Mission began prior to NASA acceptance of the first flight unit in 1999 and will continue until the de-commission of the International Space Station that is planned for 20xx. Mission engineering of the MPLM program requires a broad focus on three distinct yet inter-related operations processes: pre-flight, flight operations, and post-flight turn-around. Within each primary area exist several complex subsets of distinct and inter-related activities. Pre-flight processing includes the evaluation of carrier hardware readiness for space flight. This includes integration of payload into the carrier, integration of the carrier into the launch vehicle, and integration of the carrier onto the orbital platform. Flight operations include the actual carrier operations during flight and any required real-time ground support. Post-flight processing includes de-integration of the carrier hardware from the launch vehicle, de-integration of the payload, and preparation for returning the carrier to pre-flight staging. Typical space operations are engineered around the requirements and objectives of a dedicated mission on a dedicated operational platform (i.e. Launch or Orbiting Vehicle). The MPLM, however, has expanded this envelope by requiring operations with both vehicles during flight as well as pre-launch and post-landing operations. These unique requirements combined with a success-oriented schedule of four flights within a ten-month period have provided numerous opportunities for understanding and improving operations processes. Furthermore, it has increased the knowledge base of future Payload Carrier and Launch Vehicle hardware and requirement developments. Discussion of the process flows and target areas for process improvement are provided in the subject paper. Special emphasis is also placed on supplying guidelines for hardware development. The combination of process knowledge and hardware development knowledge will provide a comprehensive overview for future vehicle developments as related to integration and transportation of payloads.

Insight into carrier lifetime impact on band-modulation devices

NASA Astrophysics Data System (ADS)

Parihar, Mukta Singh; Lee, Kyung Hwa; Park, Hyung Jin; Lacord, Joris; Martinie, Sébastien; Barbé, Jean-Charles; Xu, Yue; El Dirani, Hassan; Taur, Yuan; Cristoloveanu, Sorin; Bawedin, Maryline

2018-05-01

A systematic study to model and characterize the band-modulation Z2-FET device is developed bringing light to the relevance of the carrier lifetime influence. This work provides guidelines to optimize the Z2-FETs for sharp switching, ESD protection, and 1T-DRAM applications. Lower carrier lifetime in the Z2-FET helps in attaining the sharp switch. We provide new insights into the correlation between generation/recombination, diffusion, electrostatic barriers and carrier lifetime.

Charlie, Development of a Light-Weight, Virtual Reality Trainer for the LSO Community: Time to Make the Leap Toward Immersive VR

DTIC Science & Technology

2015-09-01

Training System ARB Aircraft Recovery Bulletins AR Augmented Reality CAG Carrier Air Group CATCC Carrier Air Traffic Control Center COTS...in integration of an optical lens systems into the aircraft carrier. The current generation of optical lens systems integrated into aircraft ...The use of MOVLAS on an aircraft carrier represents a direct communication link between the LSO and pilot. As a backup landing aid system to

A Novel Bio-carrier Fabricated Using 3D Printing Technique for Wastewater Treatment

PubMed Central

Dong, Yang; Fan, Shu-Qian; Shen, Yu; Yang, Ji-Xiang; Yan, Peng; Chen, You-Peng; Li, Jing; Guo, Jin-Song; Duan, Xuan-Ming; Fang, Fang; Liu, Shao-Yang

2015-01-01

The structure of bio-carriers is one of the key operational characteristics of a biofilm reactor. The goal of this study is to develop a series of novel fullerene-type bio-carriers using the three-dimensional printing (3DP) technique. 3DP can fabricate bio-carriers with more specialized structures compared with traditional fabrication processes. In this research, three types of fullerene-type bio-carriers were fabricated using the 3DP technique and then compared with bio-carrier K3 (from AnoxKaldnes) in the areas of physicochemical properties and biofilm growth. Images acquired by 3D profiling and SEM indicated that the surface roughness of the 3DP bio-carrier was greater than that of K3. Furthermore, contact angle data indicated that the 3DP bio-carriers were more hydrophilic than K3. The biofilm on the 3DP bio-carriers exhibited higher microbial activity and stronger adhesion ability. These findings were attributed to excellent mass transfer of the substrate (and oxygen) between the vapour-liquid-solid tri-phase system and to the surface characteristics. It is concluded that the novel 3DP fullerene-type bio-carriers are ideal carriers for biofilm adherence and growth. PMID:26202477

Auxin Influx Carriers Control Vascular Patterning and Xylem Differentiation in Arabidopsis thaliana

PubMed Central

Siligato, Riccardo; Alonso, Jose M.; Swarup, Ranjan; Bennett, Malcolm J.; Mähönen, Ari Pekka; Caño-Delgado, Ana I.; Ibañes, Marta

2015-01-01

Auxin is an essential hormone for plant growth and development. Auxin influx carriers AUX1/LAX transport auxin into the cell, while auxin efflux carriers PIN pump it out of the cell. It is well established that efflux carriers play an important role in the shoot vascular patterning, yet the contribution of influx carriers to the shoot vasculature remains unknown. Here, we combined theoretical and experimental approaches to decipher the role of auxin influx carriers in the patterning and differentiation of vascular tissues in the Arabidopsis inflorescence stem. Our theoretical analysis predicts that influx carriers facilitate periodic patterning and modulate the periodicity of auxin maxima. In agreement, we observed fewer and more spaced vascular bundles in quadruple mutants plants of the auxin influx carriers aux1lax1lax2lax3. Furthermore, we show AUX1/LAX carriers promote xylem differentiation in both the shoot and the root tissues. Influx carriers increase cytoplasmic auxin signaling, and thereby differentiation. In addition to this cytoplasmic role of auxin, our computational simulations propose a role for extracellular auxin as an inhibitor of xylem differentiation. Altogether, our study shows that auxin influx carriers AUX1/LAX regulate vascular patterning and differentiation in plants. PMID:25922946

A Novel Bio-carrier Fabricated Using 3D Printing Technique for Wastewater Treatment.

PubMed

Dong, Yang; Fan, Shu-Qian; Shen, Yu; Yang, Ji-Xiang; Yan, Peng; Chen, You-Peng; Li, Jing; Guo, Jin-Song; Duan, Xuan-Ming; Fang, Fang; Liu, Shao-Yang

2015-07-23

The structure of bio-carriers is one of the key operational characteristics of a biofilm reactor. The goal of this study is to develop a series of novel fullerene-type bio-carriers using the three-dimensional printing (3DP) technique. 3DP can fabricate bio-carriers with more specialized structures compared with traditional fabrication processes. In this research, three types of fullerene-type bio-carriers were fabricated using the 3DP technique and then compared with bio-carrier K3 (from AnoxKaldnes) in the areas of physicochemical properties and biofilm growth. Images acquired by 3D profiling and SEM indicated that the surface roughness of the 3DP bio-carrier was greater than that of K3. Furthermore, contact angle data indicated that the 3DP bio-carriers were more hydrophilic than K3. The biofilm on the 3DP bio-carriers exhibited higher microbial activity and stronger adhesion ability. These findings were attributed to excellent mass transfer of the substrate (and oxygen) between the vapour-liquid-solid tri-phase system and to the surface characteristics. It is concluded that the novel 3DP fullerene-type bio-carriers are ideal carriers for biofilm adherence and growth.

[Development of a hepatitis B virus carrier transgenic mice model].

PubMed

Caner, Müge; Arat, Sezen; Bircan, Rifat

2008-01-01

The studies for the development of transgenic mice models which provide important profits for the studies concerning immunopathogenesis of hepatitis B virus (HBV) infections are in progress since 20 years. For this purpose different lineages bearing whole HBV genome or selected viral genes have been developed and their usage in clarifying the HBV replication and pathogenesis mechanisms have been emphasized. The aim of this study was to develop and breed a HBV carrier mice model. In the study the full HBV genome has been transferred to mouse embryos by microinjection procedure. Following transgenic manipulation, the HBV carriers among the daughter mice have been detected by molecular methods in which HBV-DNA replication and expression have been shown. The manipulations for transgene transfers have been performed in TUBITAK Marmara Research Center Transgene Laboratory, Gebze, Istanbul. The HBV-DNA carrier mice have been demonstrated by polymerase chain reaction (PCR) using the DNA samples obtained from tail tissues and also by dot-blot hybridization of the mice sera. Integrated HBV-DNA has been detected by applying in-situ hybridization to the liver tissue sections. HBV-DNA expression has been shown by reverse transcriptase PCR method with total RNA molecules that have been isolated from the liver tissues of the HBV-DNA carrier mice. HBsAg has been detected in the liver by immunohistochemical method, and HBsAg and HBeAg have additionally been demonstrated by ELISA. HBV genome, expression of the genome and the expression products have been determined in approximately 10% of the mice of which HBV-DNA have been transferred. By inbreeding heterozygote carrier mice, homozygote HBV transgenic mice line have been obtained. These HBV transgenic mice are the first lineages developed in our country. It is hopefully thought that this HBV carrier transgenic mouse model may contribute to the studies on the pathogenesis of HBV infections which are important health problems in the world as well as in Turkey.

Sabot high speed interceptor AE 4273 aircraft design

NASA Technical Reports Server (NTRS)

Dober, Dave; Al-Hashel, Waleed; Baldocchi, Bob; Berg, Tim; Lindsay, Curt; Mcatee, Aaron; Sergent, Dan; Dunbrack, Harry

1992-01-01

Today's carrier based deck launched intercept (DLI) mission is a vital one that is aimed at protecting the carrier battle group and detering potential adversaries. The assets deployed on our carrier decks are able to complete this mission but with very limited range. The waverider concept has great potential to increase the range of this carrier based mission. As a result, a request for proposals (RFP) was developed which contains design requirements for an aircraft that can complete this mission through the utilization of waverider technology.

Recent Advances in Subunit Vaccine Carriers

PubMed Central

Vartak, Abhishek; Sucheck, Steven J.

2016-01-01

The lower immunogenicity of synthetic subunit antigens, compared to live attenuated vaccines, is being addressed with improved vaccine carriers. Recent reports indicate that the physio-chemical properties of these carriers can be altered to achieve optimal antigen presentation, endosomal escape, particle bio-distribution, and cellular trafficking. The carriers can be modified with various antigens and ligands for dendritic cells targeting. They can also be modified with adjuvants, either covalently or entrapped in the matrix, to improve cellular and humoral immune responses against the antigen. As a result, these multi-functional carrier systems are being explored for use in active immunotherapy against cancer and infectious diseases. Advancing technology, improved analytical methods, and use of computational methodology have also contributed to the development of subunit vaccine carriers. This review details recent breakthroughs in the design of nano-particulate vaccine carriers, including liposomes, polymeric nanoparticles, and inorganic nanoparticles. PMID:27104575

The HBV DNA cutoff value for discriminating patients with HBeAgnegative chronic hepatitis B from inactive carriers.

PubMed

Kim, Eun Sun; Seo, Yeon Seok; Keum, Bora; Kim, Ji Hoon; A, Hyonggin; Yim, Hyung Joon; Kim, Yong Sik; Jeen, Yoon Tae; Lee, Hong Sik; Chun, Hoon Jai; Um, Soon Ho; Duck Kim, Chang; Ryu, Ho Sang

2011-05-01

Patients with HBeAg-negative chronic hepatitis B (CHB) has a significantly different prognosis than inactive carriers; there is however, no reliable strategy for accurately differentiating these two disease conditions. To determine a strategy for discriminating patients with HBeAg-negative CHB from inactive carriers. Consecutive inactive carriers (i.e. HBeAg-negativity, anti-HBe-positivity, normal ALT levels, and HBV DNA < 2000 IU/mL) were enrolled. HBV reactivation was defined as the elevation of the HBV DNA level to ≥ 2000 IU/mL. Patients were classified into true inactive carriers when their HBV DNA levels remained at < 2000 IU/mL or false inactive carriers when their HBV DNA levels increased to ≥ 2000 IU/mL during the first year. The Mean ± SD age of 208 inactive carriers (140 males) was 47.7 ± 12.6 years. The Mean ± SD serum ALT and HBV DNA levels were 22.8 ± 8.6 IU/L and 360 ± 482 IU/mL, respectively. HBV reactivation developed in 41 (19.7%) patients during the first year. Baseline HBV DNA and ALT levels differed significantly between true inactive and false inactive carriers. The AUROCs of the baseline ALT and HBV DNA levels for predicting a false inactive carrier were 0.609 and 0.831, respectively. HBV reactivation developed more often in patients with a baseline HBV DNA level of ≥ 200 IU/mL than in those with a baseline HBV DNA level of < 200 IU/mL during a Mean ± SD follow-up of 622 ± 199 days. The HBV DNA level was useful for discriminating patients with HBeAg-negative CHB from true inactive carriers. The follow-up strategies applied to inactive carriers need to vary with their HBV DNA levels.

[Effect of free and polymer carrier encapsulated doxorubicin towards HCT116 cells of human colorectal carcinoma].

PubMed

Sen'kiv, Iu V; Heffeter, P; Riabtseva, A O; Boĭko, N M; Mitina, N Ie; Zaichenko, O S; Berger, W; Stoĭka, R S

2013-01-01

Development of novel nanoscale functionalized carriers is nowadays one of the most urgent problems in cancer treatment. The aim of our study was to compare the antineoplastic effect of free doxorubicin and its complex with a nanoscale polymeric carrier towards HTC116 colorectal carcinoma cells. It was established that application of the complex of poly(5-tret-butylperoxy)-5-methyl-1-hexene-3-in-co-glycydyl metacrylat)-graft-polyethyleneglycol (poly(VEP-GMA-PEG)-graft-PEG), where VEP--5-tret-butylperoxy)-5-methyl-1-hexene-3-in; GMA--glycydyl metacrylat; graft-PEG--graft-polyethyleneglycol accordingly, functionalized with phosphatidylcholine for doxorubicin delivery increased 10 times the efficiency of cytotoxic action of this drug, as compared wich such efficiency in case of the action of free doxorubicin. The encapsulated form of doxorubicin caused more intensive cleavage of the reparation enzyme PARP and longer delay in G2/M cell cycle arrest, compared to such effects of free doxorubicin. The developed carrier itself is non-toxic to the used mammalian cells and does not cause impairment in their cell cycle. A deletion in both alleles of p53 gene did not affect the antineoplastic action of doxorubicin that was immobilized on the nanoscale carrier. Thus, p53-dependent signaling pathways are not involved in the cytotoxic action of doxorubicin-carrier complex. It is suggested that novel nanoscale polymeric carrier poly(VEP-GMA-PEG)-graft-PEG functionalized with phosphatidylcholine could be a promising carrier for targeted delivery of anticancer drugs.

Microfluidics-assisted in vitro drug screening and carrier production

PubMed Central

Tsui, Jonathan H.; Lee, Woohyuk; Pun, Suzie H.; Kim, Jungkyu; Kim, Deok-Ho

2013-01-01

Microfluidic platforms provide several unique advantages for drug development. In the production of drug carriers, physical properties such as size and shape, and chemical properties such as drug composition and pharmacokinetic parameters, can be modified simply and effectively by tuning the flow rate and geometries. Large numbers of carriers can then be fabricated with minimal effort and with little to no batch-to-batch variation. Additionally, cell or tissue culture models in microfluidic systems can be used as in vitro drug screening tools. Compared to in vivo animal models, microfluidic drug screening platforms allow for high-throughput and reproducible screening at a significantly lower cost, and when combined with current advances in tissue engineering, are also capable of mimicking native tissues. In this review, various microfluidic platforms for drug and gene carrier fabrication are reviewed to provide guidelines for designing appropriate carriers. In vitro microfluidic drug screening platforms designed for high-throughput analysis and replication of in vivo conditions are also reviewed to highlight future directions for drug research and development. PMID:23856409

From Composition to Cure: A Systems Engineering Approach to Anticancer Drug Carriers.

PubMed

MacEwan, Sarah R; Chilkoti, Ashutosh

2017-06-06

The molecular complexity and heterogeneity of cancer has led to a persistent, and as yet unsolved, challenge to develop cures for this disease. The pharmaceutical industry focuses the bulk of its efforts on the development of new drugs, but an alternative approach is to improve the delivery of existing drugs with drug carriers that can manipulate when, where, and how a drug exerts its therapeutic effect. For the treatment of solid tumors, systemically delivered drug carriers face significant challenges that are imposed by the pathophysiological barriers that lie between their site of administration and their site of therapeutic action in the tumor. Furthermore, drug carriers face additional challenges in their translation from preclinical validation to clinical approval and adoption. Addressing this diverse network of challenges requires a systems engineering approach for the rational design of optimized carriers that have a realistic prospect for translation from the laboratory to the patient. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

An Investigation of Factors Affecting How Engineers and Scientists Seek Information

NASA Technical Reports Server (NTRS)

Anderson, Claire J; Glassman, Myron; McAfee, R. Bruce; Pinelli, Thomas

2001-01-01

This study investigated how 872 US aerospace scientists and engineers select information carriers. When considering oral and written information carriers, the principle of least effort was supported with a strong preference for oral communication over written communication. In examining how the respondents select written carriers, the decision to use or not to use a written carrier was found to be primarily a function of the perceived importance of the carrier's information to a person's work. Task uncertainty and task complexity were found to be significant, but not the primary nor a totally consistent criteria. The perceived quality and accessibility of written carriers were not found significant. The findings reinforce the need for firms to hire knowledgeable employees, to provide them with comprehensive training programs, and to develop formal and informal communication networks.

The Research and Applications of Quantum Dots as Nano-Carriers for Targeted Drug Delivery and Cancer Therapy

NASA Astrophysics Data System (ADS)

Zhao, Mei-Xia; Zhu, Bing-Jie

2016-04-01

Quantum dots (QDs), nano-carriers for drugs, can help realize the targeting of drugs, and improve the bioavailability of drugs in biological fields. And, a QD nano-carrier system for drugs has the potential to realize early detection, monitoring, and localized treatments of specific disease sites. In addition, QD nano-carrier systems for drugs can improve stability of drugs, lengthen circulation time in vivo, enhance targeted absorption, and improve the distribution and metabolism process of drugs in organization. So, the development of QD nano-carriers for drugs has become a hotspot in the fields of nano-drug research in recent years. In this paper, we review the advantages and applications of the QD nano-carriers for drugs in biological fields.

Development of Scanning Ultrafast Electron Microscope Capability.

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

Collins, Kimberlee Chiyoko; Talin, Albert Alec; Chandler, David W.

Modern semiconductor devices rely on the transport of minority charge carriers. Direct examination of minority carrier lifetimes in real devices with nanometer-scale features requires a measurement method with simultaneously high spatial and temporal resolutions. Achieving nanometer spatial resolutions at sub-nanosecond temporal resolution is possible with pump-probe methods that utilize electrons as probes. Recently, a stroboscopic scanning electron microscope was developed at Caltech, and used to study carrier transport across a Si p-n junction [ 1 , 2 , 3 ] . In this report, we detail our development of a prototype scanning ultrafast electron microscope system at Sandia National Laboratoriesmore » based on the original Caltech design. This effort represents Sandia's first exploration into ultrafast electron microscopy.« less

Abnormal trajectories in cerebellum and brainstem volumes in carriers of the fragile X premutation.

PubMed

Wang, Jun Yi; Hessl, David; Hagerman, Randi J; Simon, Tony J; Tassone, Flora; Ferrer, Emilio; Rivera, Susan M

2017-07-01

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder typically affecting male premutation carriers with 55-200 CGG trinucleotide repeat expansions in the FMR1 gene after age 50. The aim of this study was to examine whether cerebellar and brainstem changes emerge during development or aging in late life. We retrospectively analyzed magnetic resonance imaging scans from 322 males (age 8-81 years). Volume changes in the cerebellum and brainstem were contrasted with those in the ventricles and whole brain. Compared to the controls, premutation carriers without FXTAS showed significantly accelerated volume decrease in the cerebellum and whole brain, flatter inverted U-shaped trajectory of the brainstem, and larger ventricles. Compared to both older controls and premutation carriers without FXTAS, carriers with FXTAS exhibited significant volume decrease in the cerebellum and whole brain and accelerated volume decrease in the brainstem. We therefore conclude that cerebellar and brainstem volumes were likely affected during both development and progression of neurodegeneration in premutation carriers, suggesting that interventions may need to start early in adulthood to be most effective. Copyright © 2017 Elsevier Inc. All rights reserved.

Investigation of correlation between open-circuit voltage deficit and carrier recombination rates in Cu(In,Ga)(S,Se)2-based thin-film solar cells

NASA Astrophysics Data System (ADS)

Chantana, Jakapan; Kato, Takuya; Sugimoto, Hiroki; Minemoto, Takashi

2018-04-01

The temperature-illumination-dependent open-circuit voltage (VOC) method is utilized to separately and quantitatively estimate carrier recombination rates at the buffer/absorber interface, in the space-charge region (SCR), and in the quasi-neutral region (QNR) of Cu(In,Ga)(S,Se)2 (CIGSSe)-based thin-film solar cells with various device structures. The correlation between open-circuit voltage deficits (VOC,def) among the carrier recombination rates of the CIGSSe solar cells with a conversion efficiency (η) above 17% is examined. It is revealed that VOC,def is decreased to 0.373 V with the reduced carrier recombination rate at the buffer/absorber interface through the development of device structures. To further decrease VOC,def (for the improved η), the carrier recombination rates in SCR and QNR are essential to be reduced by the further improvement of CIGSSe quality. Consequently, understanding the quantitative carrier recombination rates across the device, estimated from the temperature-illumination-dependent VOC method, is practical to know which part of the solar cell needs to be developed for high η above 20%.

Useful Life Prediction for Payload Carrier Hardware

NASA Technical Reports Server (NTRS)

Ben-Arieh, David

2002-01-01

The Space Shuttle has been identified for use through 2020. Payload carrier systems will be needed to support missions through the same time frame. To support the future decision making process with reliable systems, it is necessary to analyze design integrity, identify possible sources of undesirable risk and recognize required upgrades for carrier systems. This project analyzed the information available regarding the carriers and developed the probability of becoming obsolete under different scenarios. In addition, this project resulted in a plan for an improved information system that will improve monitoring and control of the various carriers. The information collected throughout this project is presented in this report as process flow, historical records, and statistical analysis.

A transmission-grating-modulated pump-probe absorption spectroscopy and demonstration of diffusion dynamics of photoexcited carriers in bulk intrinsic GaAs film.

PubMed

Chen, Ke; Wang, Wenfang; Chen, Jianming; Wen, Jinhui; Lai, Tianshu

2012-02-13

A transmission-grating-modulated time-resolved pump-probe absorption spectroscopy is developed and formularized. The spectroscopy combines normal time-resolved pump-probe absorption spectroscopy with a binary transmission grating, is sensitive to the spatiotemporal evolution of photoinjected carriers, and has extensive applicability in the study of diffusion transport dynamics of photoinjected carriers. This spectroscopy has many advantages over reported optical methods to measure diffusion dynamics, such as simple experimental setup and operation, and high detection sensitivity. The measurement of diffusion dynamics is demonstrated on bulk intrinsic GaAs films. A carrier density dependence of carrier diffusion coefficient is obtained and agrees well with reported results.

Influence of Preferred Orientation on the Electrical Conductivity of Fluorine-Doped Tin Oxide Films

PubMed Central

Wang, Jian Tao; Shi, Xiang Lei; Liu, Wei Wei; Zhong, Xin Hua; Wang, Jian Nong; Pyrah, Leo; Sanderson, Kevin D.; Ramsey, Philip M.; Hirata, Masahiro; Tsuri, Keiko

2014-01-01

Current development of high-performance transparent conductive oxide (TCO) films is limited with tradeoff between carrier mobility and concentration since none of them can be improved without sacrificing the other. In this study, we prepare fluorine doped tin oxide (FTO) films by chemical vapor deposition with inclusions of different additives and report that the mobility can be varied from 0.65 to 28.5 cm2 V−1 s−1 without reducing the achieved high carrier concentration of 4 × 1020 cm−3. Such an increase in mobility is shown to be clearly associated with the development of (200) preferred orientation (PO) but concurrent degradation of (110) PO in films. Thus, at a constant high carrier concentration, the electrical conductivity can be improved via carrier mobility simply by PO control. Such a one-step approach avoiding conventional post-deposition treatment is suggested for developing next-generation FTO as well as other TCO films with better than ever conductivities. PMID:24419455

2017 SmartWay Multimodal Carrier Tool Demonstration

EPA Pesticide Factsheets

This EPA presentation provides information on the SmartWay Multimodal Carrier Tool: its background and development, participation in the program, application process, emission metrics, tool demonstration, data collection, and schedule for 2017.

49 CFR 1.86 - The Federal Motor Carrier Safety Administration.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., development, and technology transfer activities to promote safety of operation and equipment of motor vehicles for the motor carrier transportation program; and (f) Carrying out an effective communications and...

49 CFR 1.86 - The Federal Motor Carrier Safety Administration.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., development, and technology transfer activities to promote safety of operation and equipment of motor vehicles for the motor carrier transportation program; and (f) Carrying out an effective communications and...

49 CFR 1.86 - The Federal Motor Carrier Safety Administration.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., development, and technology transfer activities to promote safety of operation and equipment of motor vehicles for the motor carrier transportation program; and (f) Carrying out an effective communications and...

Development of a fragile X syndrome (FXS) knowledge scale: towards a modified multidimensional measure of informed choice for FXS population carrier screening.

PubMed

Ames, Alice G; Jaques, Alice; Ukoumunne, Obioha C; Archibald, Alison D; Duncan, Rony E; Emery, Jon; Metcalfe, Sylvia A

2015-02-01

Genetic carrier screening is increasingly possible for many conditions, but it is important to ensure decisions are informed. The multidimensional measure of informed choice (MMIC) is a quantitative instrument developed to evaluate informed choice in prenatal screening for Down syndrome, measuring knowledge, attitudes and uptake. To apply the MMIC in other screening settings, the knowledge scale must be modified. To develop and validate a modified MMIC knowledge scale for use with women undergoing carrier screening for fragile X syndrome (FXS). Responses to MMIC items were collected through questionnaires as part of a FXS carrier screening pilot study in a preconception setting in Melbourne, Australia. Ten knowledge scale items were developed using a modified Delphi technique. Cronbach's alpha and factor analysis were used to validate the new FXS knowledge scale. We summarized the knowledge, attitudes and informed choice status based on the modified MMIC. Two hundred and eighty-five women were recruited, 241 eligible questionnaires were complete for analysis. The FXS knowledge scale items measured one salient construct and were internally consistent (alpha = 0.70). 71% (172/241) of participants were classified as having good knowledge, 70% (169/241) had positive attitudes and 27% (65/241) made an informed choice to accept or decline screening. We present the development of a knowledge scale as part of a MMIC to evaluate informed choice in population carrier screening for FXS. This can be used as a template by other researchers to develop knowledge scales for other conditions for use in the MMIC. © 2012 John Wiley & Sons Ltd.

Risk of Japanese carriers of hyperphosphorylated paratarg-7, the first autosomal-dominantly inherited risk factor for hematological neoplasms, to develop monoclonal gammopathy of undetermined significance and multiple myeloma.

PubMed

Grass, Sandra; Iida, Shinsuke; Wikowicz, Aleksandra; Preuss, Klaus-Dieter; Inagaki, Atsushi; Shimizu, Kazuyuki; Ziepert, Marita; Ueda, Ryuzo; Pfreundschuh, Michael

2011-03-01

Hyperphosphorylated paratarg-7 (pP-7) is a frequent target of paraproteins in German patients with monoclonal gammopathy of undetermined significance (MGUS)/multiple myeloma (MM). The frequency of MGUS/MM is lower in Japan than in Europe. As pP-7, the first molecularly defined autosomal-dominant risk factor for any hematological neoplasm, is inherited in a dominant fashion, we determined the incidence of the pP-7 carrier state in a Japanese population, and compared the frequency of pP-7-specific paraproteins and the pP-7 carrier state in Japanese and German patients with MGUS/MM. Peripheral blood from 111 Japanese patients with MGUS/MM and 278 healthy blood donors was analyzed for the pP-7 carrier state by isoelectric focusing and for pP-7-specific antibodies by ELISA. The Japanese group was compared with 252 German MGUS/MM patients and 200 healthy controls. Five of 111 (4.5%) Japanese and 35/252 (13.9%) German IgA/IgG MGUS/MM patients had a pP-7-specific paraprotein (P=0.009). The prevalence of healthy pP-7 carriers in the Japanese study group was 1/278 (0.36%), whereas it was 4/200 in the German group (P=0.166). The relative risk for pP-7 carriers developing MGUS/MM had an odds ratio of 13.1 in the Japanese and 7.9 in the German group. In conclusion, the fraction of pP-7 carriers with a pP-7-specific paraprotein is lower among Japanese than in German patients with MGUS/MM, but pP-7 carriers in both ethnic groups have a high risk of developing MGUS/MM. © 2011 Japanese Cancer Association.

Density Functional Theory Calculations of Activation Energies for Carrier Capture by Defects in Semiconductors

NASA Astrophysics Data System (ADS)

Modine, N. A.; Wright, A. F.; Lee, S. R.

The rate of defect-induced carrier recombination is determined by both defect levels and carrier capture cross-sections. Density functional theory (DFT) has been widely and successfully used to predict defect levels, but only recently has work begun to focus on using DFT to determine carrier capture cross-sections. Lang and Henry developed the theory of carrier-capture by multiphonon emission in the 1970s and showed that carrier-capture cross-sections differ between defects primarily due to differences in their carrier capture activation energies. We present an approach to using DFT to calculate carrier capture activation energies that does not depend on an assumed configuration coordinate and that fully accounts for anharmonic effects, which can substantially modify carrier activation energies. We demonstrate our approach for intrinisic defects in GaAs and GaN and discuss how our results depend on the choice of exchange-correlation functional and the treatment of spin polarization. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

14 CFR 158.20 - Submission of required documents.

Code of Federal Regulations, 2014 CFR

2014-01-01

... due to the security process. (b) Once the database development is completed with air carrier capability, public agencies and air carriers may use the FAA's national PFC database to post their required...

14 CFR 158.20 - Submission of required documents.

Code of Federal Regulations, 2012 CFR

2012-01-01

... due to the security process. (b) Once the database development is completed with air carrier capability, public agencies and air carriers may use the FAA's national PFC database to post their required...

14 CFR 158.20 - Submission of required documents.

Code of Federal Regulations, 2011 CFR

2011-01-01

... due to the security process. (b) Once the database development is completed with air carrier capability, public agencies and air carriers may use the FAA's national PFC database to post their required...

14 CFR 158.20 - Submission of required documents.

Code of Federal Regulations, 2013 CFR

2013-01-01

... due to the security process. (b) Once the database development is completed with air carrier capability, public agencies and air carriers may use the FAA's national PFC database to post their required...

14 CFR 158.20 - Submission of required documents.

Code of Federal Regulations, 2010 CFR

2010-01-01

... due to the security process. (b) Once the database development is completed with air carrier capability, public agencies and air carriers may use the FAA's national PFC database to post their required...

Long term verbal memory recall deficits in fragile X premutation females.

PubMed

Shelton, Annie L; Cornish, Kim; Fielding, Joanne

2017-10-01

Carriers of a FMR1 premutation allele (between 55 and 199 CGG repeats) are at risk of developing a wide range of medical, psychiatric and cognitive disorders, including executive dysfunction. These cognitive deficits are often less severe for female premutation carriers compared to male premutation carriers, albeit similar in nature. However, it remains unclear whether female premutation carriers who exhibit executive dysfunction also report verbal learning and memory deficits like those of their male counterparts. Here we employed the CVLT to assess verbal learning and memory function in 19 female premutation carriers, contrasting performance with 19 age- and IQ-matched controls. Group comparisons revealed similar performance during the learning and short delay recall phases of the CVLT. However, after a long delay period, female premutation carriers remembered fewer words for both free and cued recall trials, but not during recognition trials. These findings are consistent with reports for male premutation carriers, and suggest that aspects of long term memory may be adversely affect in a subgroup of premutation carriers with signs of executive dysfunction. Copyright © 2017. Published by Elsevier Inc.

Delineation of the working memory profile in female FMR1 premutation carriers: the effect of cognitive load on ocular motor responses.

PubMed

Shelton, Annie L; Cornish, Kim M; Godler, David E; Clough, Meaghan; Kraan, Claudine; Bui, Minh; Fielding, Joanne

2015-04-01

Fragile X mental retardation 1 (FMR1) premutation carriers (PM-carriers) are characterised as having mid-sized expansions of between 55 and 200 CGG repeats in the 5' untranslated region of the FMR1 gene. While there is evidence of executive dysfunction in PM-carriers, few studies have explicitly explored working memory capabilities in female PM-carriers. 14 female PM-carriers and 13 age- and IQ-matched healthy controls completed an ocular motor n-back working memory paradigm. This task examined working memory ability and the effect of measured increases in cognitive load. Female PM-carriers were found to have attenuated working memory capabilities. Increasing the cognitive load did not elicit the expected reciprocal increase in the task errors for female PM-carriers, as it did in controls. However female PM-carriers took longer to respond than controls, regardless of the cognitive load. Further, FMR1 mRNA levels were found to significantly predict PM-carrier response time. Although preliminary, these findings provide further evidence of executive dysfunction, specifically disruption to working memory processes, which were found to be associated with increases in FMR1 mRNA expression in female PM-carriers. With future validation, ocular motor paradigms such as the n-back paradigm will be critical to the development of behavioural biomarkers for identification of PM-carrier cognitive-affective phenotypes. Copyright © 2015 Elsevier B.V. All rights reserved.

Virtualization for the LHCb Online system

NASA Astrophysics Data System (ADS)

Bonaccorsi, Enrico; Brarda, Loic; Moine, Gary; Neufeld, Niko

2011-12-01

Virtualization has long been advertised by the IT-industry as a way to cut down cost, optimise resource usage and manage the complexity in large data-centers. The great number and the huge heterogeneity of hardware, both industrial and custom-made, has up to now led to reluctance in the adoption of virtualization in the IT infrastructure of large experiment installations. Our experience in the LHCb experiment has shown that virtualization improves the availability and the manageability of the whole system. We have done an evaluation of available hypervisors / virtualization solutions and find that the Microsoft HV technology provides a high level of maturity and flexibility for our purpose. We present the results of these comparison tests, describing in detail, the architecture of our virtualization infrastructure with a special emphasis on the security for services visible to the outside world. Security is achieved by a sophisticated combination of VLANs, firewalls and virtual routing - the cost and benefits of this solution are analysed. We have adapted our cluster management tools, notably Quattor, for the needs of virtual machines and this allows us to migrate smoothly services on physical machines to the virtualized infrastructure. The procedures for migration will also be described. In the final part of the document we describe our recent R&D activities aiming to replacing the SAN-backend for the virtualization by a cheaper iSCSI solution - this will allow to move all servers and related services to the virtualized infrastructure, excepting the ones doing hardware control via non-commodity PCI plugin cards.

Validation of Filtration Skid During Land-Based & Shipboard Tests

DTIC Science & Technology

2012-10-12

b. ABSTRACT c. THIS PAGE 19b. TELEPHONE NUMBER (include area code) Standard Form 298 (Re . 8-98) v Prescribed by ANSI Std. Z39.18 12...skid device that it had previously developed. A prototype unit was developed and deployed on the bulk carrier M/ V Indiana Harbor, and commissioning...a preliminary design of a filter skid device that it had previously developed. A prototype unit was developed and deployed on the bulk carrier M/ V

Effects of Carriers, Emulsifiers, and Biopesticides for Direct Silk Treatments on Caterpillar Feeding Damage and Ear Development in Sweet Corn.

PubMed

Westgate, P J; Schultz, B B; Hazzard, R V

2017-04-01

In the northeastern United States, control of Lepidopteran pests of sweet corn, particularly corn earworm [Helicoverpa zea (Boddie)], is difficult using organic methods. The direct application of corn oil and Bacillus thuringiensis (Bt) to corn silk has been shown to reduce ear damage from corn earworm in past studies; these studies sought to optimize this method by evaluating additional carrier and biopesticide mixtures that comply with the United States Federal Insecticide, Fungicide, and Rodenticide Act and National Organic Standards. Carriers, which are liquids used to dissolve the biopesticide and deliver it into the tip of the ear, may have phytotoxic or insecticidal properties. Experiments conducted from 2001 to 2005 evaluated caterpillar damage and ear development effects from carriers (vegetable and paraffinic oils and carrageenan), biopesticides (Bt, spinsosad, and neem), and three emulsifiers in various combinations when applied directly to the tips of the ears 5-7 d after silk initiation. There were no effects of emulsifiers on ear quality, except for slight reduction in caterpillar damage in one of the two years. There were no differences among corn, soy, canola, and safflower oils in corn earworm control or tip development. The carrageenan carrier had the least effect upon ear development as measured by the length of nonpollinated kernels at the tip, compared to corn oil or paraffinic oil (JMS Stylet Oil), which caused the greatest tip damage as well as an oily discoloration. The carrier-pesticide combinations with the best ear quality overall were spinosad in carrageenan or corn oil, and Bt in carrageenan. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

I-95 corridor coalition, evaluation of field operations test 8 : electronic credentialing : results of New York state motor carrier industry survey

DOT National Transportation Integrated Search

2001-05-01

The State of New York received a grant from the I-95 Corridor Coalition to develop a proof-of-concept for an electronic credentialing system for the motor carrier industry. When fully developed, the system, which is a web-based solution, will enable ...

Enabling National Security Through Dual-Use Technology

DTIC Science & Technology

2014-04-30

Aersopace, 2014) Human Universal Load Carrier (HULC) The Human Universal Load Carrier (HULC) is an exoskeleton developed by Lockheed Martin for dismounted...HULC (Army-Technology.com, 2014). HULC is an un-tethered, hydraulic-powered, anthropomorphic exoskeleton designed specifically to fit around the...currently designed for military use, exoskeleton technology development will eventually provide civilian capabilities by enhancing firefighting

Development of high efficiency solar cells on silicon web

NASA Technical Reports Server (NTRS)

Rohatgi, A.; Meier, D. L.; Campbell, R. B.; Schmidt, D. N.; Rai-Choudhury, P.

1984-01-01

Web base material is being improved with a goal toward obtaining solar cell efficiencies in excess of 18% (AM1). Carrier loss mechanisms in web silicon was investigated, techniques were developed to reduce carrier recombination in the web, and web cells were fabricated using effective surface passivation. The effect of stress on web cell performance was also investigated.

Investigation of traveler acceptance factors in short haul air carrier operations

NASA Technical Reports Server (NTRS)

Kuhlthau, A. R.; Jacobson, I. D.

1972-01-01

The development of a mathematical model for human reaction to variables involved in transportation systems is discussed. The techniques, activities, and results related to defining certain specific inputs to the model are presented. A general schematic diagram of the problem solution is developed. The application of the model to short haul air carrier operations is examined.

Exploring the protective effects of calcium-containing carrier against drying-induced cellular injuries of probiotics using single droplet drying technique.

PubMed

Zheng, Xufeng; Fu, Nan; Huang, Song; Jeantet, Romain; Chen, Xiao Dong

2016-12-01

Protective carriers that encapsulate probiotics in spray drying could improve the survival ratio of dried cells through different mechanisms. Unveiling the protective mechanism of each carrier will contribute to a rational design of high performance carrier formulation. This study utilized single droplet drying (SDD) technique to investigate the effects of calcium cation in varied carrier formulation. Inactivation histories of Lactobacillus rhamnosus GG (LGG) in different carriers were compared, and cellular injury history of probiotics during droplet drying was studied for the first time. Adding 1mM CaCl 2 to lactose carrier protected cell viability, mitigated cellular injuries, and enhanced regrowth capability as drying progressed, demonstrating the positive effect of Ca 2+ with possible mechanism of stabilizing sub-cellular structures. At later drying stages, cell survival in Lac/Ca carrier was increased by 0.5-1.5 log on selective media compared to lactose carrier. Supplementing calcium-binding agents lowered the protective effect, shortening the initiation of rapid cell inactivation down to 120s of drying. Adding CaCl 2 to trehalose carrier barely improved cell survival, indicating that the protective effect could be influenced by carrier formulation. Pure trehalose carrier exerted excellent protection on LGG, supporting cells to regrow in liquid rich medium even after 180s of drying. The protection of trehalose may stem from stabilization of sub-cellular structures, which possibly overlap the effect of Ca 2+ . The findings suggested that high performance carrier formulation might be developed by combining carrier materials with different protective mechanisms, for maximizing the survival of active dry probiotics in industrial spray drying operation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Occurrence of phaeochromocytoma tumours in RET mutation carriers - a single-centre study.

PubMed

Kotecka-Blicharz, Agnieszka; Hasse-Lazar, Kornelia; Jurecka-Lubieniecka, Beata; Pawlaczek, Agnieszka; Oczko-Wojciechowska, Małgorzata; Bugajska, Beata; Ledwon, Aleksandra; Król, Aleksandra; Michalik, Barbara; Jarząb, Barbara

2016-01-01

Multiple endocrine neoplasia type 2 (MEN 2) is an autosomal dominant genetic syndrome caused by germline mutation in RET proto-oncogene. The most common mutations are in a cysteine rich domain. Phaeochromocytoma will develop in approximately 50% of RET proto-oncogene carriers. The studied population consisted of 228 RET proto-oncogene mutation carriers. Monitoring for the diagnosis of phaeochromocytoma was carried out in all patients with established genetic status. Mean time of follow up was 138 months. Surveillance consisted of periodically performed clinical evaluation, 24-hour urinary determinations of total metanephrines complementary with imaging (CT, MR, MIBG scintigraphy). Phaeochromocytoma developed in 41 patients (18% of all RET proto-oncogene mutations carriers). The mean age of diagnosis for the whole cohort was 43 years. In eight cases phaeochromocytoma was the first manifestation of the MEN 2 syndrome. Only eight (20%) patients were symptomatic at diagnosis of phaeochromocytoma. The mean size of the tumour was 4.3 cm. There was no extra-adrenal localisation. We observed one case of malignant phaeochromocytoma. In patients with MEN 2 syndrome phaeochromocytomas are usually benign adrenal tumours with high risk of bilateral development. Taking to account the latter risk and non-specific clinical manifestation of the neoplasm it is mandatory to screen all RET proto-oncogene mutations carriers for phaeochromocytoma.

Tool Demo Webinar: 2017 SmartWay Air Carrier Tool Demonstration

EPA Pesticide Factsheets

This EPA presentation provides information on the SmartWay Air Carrier Tool: its background and development, participation in the program, application process, emission metrics, tool demonstration, data collection, and schedule for 2017.

Engineering antiphagocytic biomimetic drug carriers

PubMed Central

Sawdon, Alicia; Peng, Ching-An

2014-01-01

Drug-delivery carriers have the potential to not only treat but also diagnose many diseases; however, they still lack the complexity of natural-particulate systems. Cell-based therapies using tumor-targeting T cells and tumor-homing mesenchymal stem cells have given researchers a means to exploit the characteristics exhibited by innate-biological entities. Similarly, immune evasion by pathogens has inspired the development of natural polymers to cloak drug carriers. The ‘marker-of-self’ CD47 protein, which is found ubiquitously on mammalian cell surfaces, has been used for evading phagocyte clearance of drug carriers. This review will focus on the recent progress of drug carriers co-opting the tricks that cells in nature use to hide safely under the radar of the body’s innate immune system. PMID:23883126

Application of two component biodegradable carriers in a particle-fixed biofilm airlift suspension reactor: development and structure of biofilms.

PubMed

Hille, Andrea; He, Mei; Ochmann, Clemens; Neu, Thomas R; Horn, Harald

2009-01-01

Two component biodegradable carriers for biofilm airlift suspension (BAS) reactors were investigated with respect to development of biofilm structure and oxygen transport inside the biofilm. The carriers were composed of PHB (polyhydroxybutyrate), which is easily degradable and PCL (caprolactone), which is less easily degradable by heterotrophic microorganisms. Cryosectioning combined with classical light microscopy and CLSM was used to identify the surface structure of the carrier material over a period of 250 days of biofilm cultivation in an airlift reactor. Pores of 50 to several hundred micrometers depth are formed due to the preferred degradation of PHB. Furthermore, microelectrode studies show the transport mechanism for different types of biofilm structures, which were generated under different substrate conditions. At high loading rates, the growth of a rather loosely structured biofilm with high penetration depths of oxygen was found. Strong changes of substrate concentration during fed-batch mode operation of the reactor enhance the growth of filamentous biofilms on the carriers. Mass transport in the outer regions of such biofilms was mainly driven by advection.

Theoretical investigation of carrier transfer by an optical contacting scheme for optoelectronic application

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

Yang, Jianfeng, E-mail: jianfeng.yang@student.unsw.edu.au; Zhang, Zhilong; Chen, Weijian

2016-04-21

As a promising charge carrier transfer scheme, optical coupling could potentially improve the performance of an optoelectronic device for energy harvesting based on well developed nanotechnology. By extracting carriers optically, the functional features of the nano-structured material could be better used by minimizing the concerns about its electrical properties. In this paper, we present a rigorous electromagnetic model to analyze the optical carrier transfer problem. The flow of the energy is analyzed carefully by the photon transfer spectrum, and the photon emitters (electron-hole pairs) are assumed in a thermal equilibrium described by Bose-Einstein distribution. The result shows that an energymore » selective carrier transfer can be optically achieved at the device level by integrating the emitter and receiver into a nano-optical resonator, where both the photon emission and absorption are significantly amplified by a near-field coupling around the resonant frequency. General design and optimization schemes in practice are addressed by examining the influence of the photonic design and an energy dependent emissivity of the emitter, which can be used to develop the optical contacting concept further.« less

Decision feedback loop for tracking a polyphase modulated carrier

NASA Technical Reports Server (NTRS)

Simon, M. K. (Inventor)

1974-01-01

A multiple phase modulated carrier tracking loop for use in a frequency shift keying system is described in which carrier tracking efficiency is improved by making use of the decision signals made on the data phase transmitted in each T-second interval. The decision signal is used to produce a pair of decision-feedback quadrature signals for enhancing the loop's performance in developing a loop phase error signal.

Charge carrier coherence and Hall effect in organic semiconductors.

PubMed

Yi, H T; Gartstein, Y N; Podzorov, V

2016-03-30

Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.

Effects of carrier concentrations on the charge transport properties in monolayer silicene

NASA Astrophysics Data System (ADS)

Abidin, B. I.; Yeoh, K. H.; Ong, D. S.; Yong, T. K.

2017-10-01

Using analytical band Monte Carlo approach, we have carried out a systematic study on the effects of carrier concentrations on the steady-state and transient electron transports that occur within a monolayer silicene. In particular, we have observed the following: First at steady-state, the electron mobility reduces with higher carrier concentrations. Secondly, in the transient regime we found that the drift velocity overshoot can be controlled by varying the carrier concentrations. We uncover that at carrier concentration of 1  ×  1013 cm-2, the drift velocity overshoot can reach up to 3.8  ×  107 cm s-1 which is close to the steady-state drift velocity saturation of graphene. Thirdly, the distance of the velocity over shoot can be further extended with higher carrier concentrations. Our findings could be useful and can be used as benchmark for future development of nanoscale silicene based devices.

Determining the role of skewed X-chromosome inactivation in developing muscle symptoms in carriers of Duchenne muscular dystrophy.

PubMed

Viggiano, Emanuela; Ergoli, Manuela; Picillo, Esther; Politano, Luisa

2016-07-01

Duchenne and Becker dystrophinopathies (DMD and BMD) are X-linked recessive disorders caused by mutations in the dystrophin gene that lead to absent or reduced expression of dystrophin in both skeletal and heart muscles. DMD/BMD female carriers are usually asymptomatic, although about 8 % may exhibit muscle or cardiac symptoms. Several mechanisms leading to a reduced dystrophin have been hypothesized to explain the clinical manifestations and, in particular, the role of the skewed XCI is questioned. In this review, the mechanism of XCI and its involvement in the phenotype of BMD/DMD carriers with both a normal karyotype or with X;autosome translocations with breakpoints at Xp21 (locus of the DMD gene) will be analyzed. We have previously observed that DMD carriers with moderate/severe muscle involvement, exhibit a moderate or extremely skewed XCI, in particular if presenting with an early onset of symptoms, while DMD carriers with mild muscle involvement present a random XCI. Moreover, we found that among 87.1 % of the carriers with X;autosome translocations involving the locus Xp21 who developed signs and symptoms of dystrophinopathy such as proximal muscle weakness, difficulty to run, jump and climb stairs, 95.2 % had a skewed XCI pattern in lymphocytes. These data support the hypothesis that skewed XCI is involved in the onset of phenotype in DMD carriers, the X chromosome carrying the normal DMD gene being preferentially inactivated and leading to a moderate-severe muscle involvement.

Motor carrier industry profile : an update 2004-2005.

DOT National Transportation Integrated Search

2005-08-01

This report updates the Motor Carrier Industry Profile: 2001-20031 and Stock Market Performance of Publicly Traded Trucking Sector Stocks by Industry Segment, 2000-20042 to reflect more recent developments of particular significance to the industry a...

49 CFR 380.201 - General requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS SPECIAL TRAINING... behind-the-wheel instruction that is designed to provide an opportunity to develop the skills outlined...

[Polymeric drug carriers activated by ultrasounds energy].

PubMed

Kik, Krzysztof; Lwow, Felicja; Szmigiero, Leszek

2007-01-01

In the last two decades an extensive research on the employment of ultrasounds in anticancer therapy has been noticed. So far ultrasounds have been widely used in medicine for diagnostic purposes (ultrasonography), but their great therapeutic potential and the development of polymer based antineoplastic drug carriers have persuaded many investigators to start research on the employment of ultrasounds in anticancer therapy. A new therapeutic concept based on the controlled drug's molecules release from their transporting polymer carriers has been proposed. Cavitation, a phenomenon characteristic for the action of ultrasounds, is used to destroy polymeric drug carriers and for drug release in target sites. The sonodynamic therapy (SDT) which utilizes ultrasonic waves for "acoustic drug activation" leading to the enhancement of cytotoxic activity of some drugs has also been developed. Furthermore, a long standing research on ultrasounds resulted in a new concept based on hyperthermia. This method of cancer treatment does not require any chemotherapeutic agent to be applied.

Histidine-lysine peptides as carriers of nucleic acids.

PubMed

Leng, Qixin; Goldgeier, Lisa; Zhu, Jingsong; Cambell, Patricia; Ambulos, Nicholas; Mixson, A James

2007-03-01

With their biodegradability and diversity of permutations, peptides have significant potential as carriers of nucleic acids. This review will focus on the sequence and branching patterns of peptide carriers composed primarily of histidines and lysines. While lysines within peptides are important for binding to the negatively charged phosphates, histidines are critical for endosomal lysis enabling nucleic acids to reach the cytosol. Histidine-lysine (HK) polymers by either covalent or ionic bonds with liposomes augment transfection compared to liposome carriers alone. More recently, we have examined peptides as sole carriers of nucleic acids because of their intrinsic advantages compared to the bipartite HK/liposome carriers. With a protocol change and addition of a histidine-rich tail, HK peptides as sole carriers were more effective than liposomes alone in several cell lines. While four-branched polymers with a primary repeating sequence pattern of -HHK- were more effective as carriers of plasmids, eight-branched polymers with a sequence pattern of -HHHK- were more effective as carriers of siRNA. Compared to polyethylenimine, HK carriers of siRNA and plasmids had reduced toxicity. When injected intravenously, HK polymers in complex with plasmids encoding antiangiogenic proteins significantly decreased tumor growth. Furthermore, modification of HK polymers with polyethylene glycol and vascular-specific ligands increased specificity of the polyplex to the tumor by more than 40-fold. Together with further development and insight on the structure of HK polyplexes, HK peptides may prove to be useful as carriers of different forms of nucleic acids both in vitro and in vivo.

Development of formulations of biological agents for management of root rot of lettuce and cucumber.

PubMed

Amer, G A; Utkhede, R S

2000-09-01

The effect of various carrier formulations of Bacillus subtilis and Pseudomonas putida were tested on germination, growth, and yield of lettuce and cucumber crops in the presence of Pythium aphanidermatum and Fusarium oxysporum f.sp. cucurbitacearum, respectively. Survival of B. subtilis and P. putida in various carriers under refrigeration (about 0 degree C) and at room temperature (about 22 degrees C) was also studied. In all carrier formulations, B. subtilis strain BACT-0 survived up to 45 days. After 45 days of storage at room temperature (about 22 degrees C), populations B. subtilis strain BACT-0 were significantly higher in vermiculite, kaolin, and bacterial broth carriers compared with other carriers. Populations of P. putida were significantly higher in vermiculite, peat moss, wheat bran, and bacterial broth than in other carriers when stored either under refrigeration (about 0 degree C) or at room temperature (about 22 degrees C) for 15 or 45 days. Germination of lettuce seed was not affected in vermiculite, talc, kaolin, and peat moss carriers, but germination was significantly reduced in alginate and bacterial broth carriers of B. subtilis compared to the non-treated control. Germination of cucumber seed was not affected by any of the carriers. Significantly higher fresh lettuce and root weights were observed in vermiculite and kaolin carriers of B. subtilis compared with P. aphanidermatum-inoculated control plants. Lettuce treated with vermiculite, and kaolin carriers of B. subtilis, or non-inoculated control lettuce plants had significantly lower root rot ratings than talc, peat moss, bacterial broth, and P. aphanidermatum-inoculated control plants. Growth and yield of cucumber plants were significantly higher in vermiculite-based carrier of P. putida than the other carriers and Fusarium oxysporum f.sp. cucurbitacearum-inoculated plants.

Carrier screening in the era of expanding genetic technology.

PubMed

Arjunan, Aishwarya; Litwack, Karen; Collins, Nick; Charrow, Joel

2016-12-01

The Center for Jewish Genetics provides genetic education and carrier screening to individuals of Jewish descent. Carrier screening has traditionally been performed by targeted mutation analysis for founder mutations with an enzyme assay for Tay-Sachs carrier detection. The development of next-generation sequencing (NGS) allows for higher detection rates regardless of ethnicity. Here, we explore differences in carrier detection rates between genotyping and NGS in a primarily Jewish population. Peripheral blood samples or saliva samples were obtained from 506 individuals. All samples were analyzed by sequencing, targeted genotyping, triplet-repeat detection, and copy-number analysis; the analyses were carried out at Counsyl. Of 506 individuals screened, 288 were identified as carriers of at least 1 condition and 8 couples were carriers for the same disorder. A total of 434 pathogenic variants were identified. Three hundred twelve variants would have been detected via genotyping alone. Although no additional mutations were detected by NGS in diseases routinely screened for in the Ashkenazi Jewish population, 26.5% of carrier results and 2 carrier couples would have been missed without NGS in the larger panel. In a primarily Jewish population, NGS reveals a larger number of pathogenic variants and provides individuals with valuable information for family planning.Genet Med 18 12, 1214-1217.

Drug composition matters: the influence of carrier concentration on the radiochemical purity, hydroxyapatite affinity and in-vivo bone accumulation of the therapeutic radiopharmaceutical 188Rhenium-HEDP.

PubMed

Lange, R; de Klerk, J M H; Bloemendal, H J; Ramakers, R M; Beekman, F J; van der Westerlaken, M M L; Hendrikse, N H; Ter Heine, R

2015-05-01

(188)Rhenium-HEDP is an effective bone-targeting therapeutic radiopharmaceutical, for treatment of osteoblastic bone metastases. It is known that the presence of carrier (non-radioactive rhenium as ammonium perrhenate) in the reaction mixture during labeling is a prerequisite for adequate bone affinity, but little is known about the optimal carrier concentration. We investigated the influence of carrier concentration in the formulation on the radiochemical purity, in-vitro hydroxyapatite affinity and the in-vivo bone accumulation of (188)Rhenium-HEDP in mice. The carrier concentration influenced hydroxyapatite binding in-vitro as well as bone accumulation in-vivo. Variation in hydroxyapatite binding with various carrier concentrations seemed to be mainly driven by variation in radiochemical purity. The in-vivo bone accumulation appeared to be more complex: satisfactory radiochemical purity and hydroxyapatite affinity did not necessarily predict acceptable bio-distribution of (188)Rhenium-HEDP. For development of new bisphosphonate-based radiopharmaceuticals for clinical use, human administration should not be performed without previous animal bio-distribution experiments. Furthermore, our clinical formulation of (188)Rhenium-HEDP, containing 10 μmol carrier, showed excellent bone accumulation that was comparable to other bisphosphonate-based radiopharmaceuticals, with no apparent uptake in other organs. Radiochemical purity and in-vitro hydroxyapatite binding are not necessarily predictive of bone accumulation of (188)Rhenium-HEDP in-vivo. The formulation for (188)Rhenium-HEDP as developed by us for clinical use exhibits excellent bone uptake and variation in carrier concentration during preparation of this radiopharmaceutical should be avoided. Copyright © 2015 Elsevier Inc. All rights reserved.

Development of a probiotic delivery system from agrowastes, soy protein isolate, and microbial transglutaminase.

PubMed

Yew, Sok-Eng; Lim, Ting-Jin; Lew, Lee-Ching; Bhat, Rajeev; Mat-Easa, Azhar; Liong, Min-Tze

2011-04-01

Probiotic delivery system was developed via the use of microbial transglutaminase (MTG) cross-linked soy protein isolate (SPI) incorporated with agrowastes such as banana peel (BE), banana pulp (BU), and pomelo rind (PR). Inoculums of Lactobacillus bulgaricus FTDC 1511 were added to the cross-linked protein matrix. The incorporation of agrowastes had significantly (P<0.05) reduced the strength, pH value, and the lightness of the SPI gel carriers, while sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles revealed that the occurring cross-links within the SPI gel carriers were attributed to the addition of MTG. Scanning electron microscope micrographs illustrated that SPI carriers containing agrowastes have exhibited a less-dense protein matrix. All the SPI carriers possessed maximum swelling ratio at 4 to 4.5 within 15 min in simulated gastric fluid (SGF), whereas the maximum swelling ratios of SPI/BE, SPI/BU, and SPI/PR were higher compared to that of control in simulated intestinal fluid (SIF). Additionally, SPI carriers in SGF medium did not show degradation of structure, whereas a major collapse of network was observed in SIF medium, indicating controlled-release in the intestines. The addition of agrowastes into SPI carriers led to a significantly (P<0.0001) lower release of L. bulgaricus FTDC 1511 in SGF medium and a higher release in SIF medium, compared to that of the control. SPI carriers containing agrowastes may be useful transports for living probiotic cells through the stomach prior to delivery in the lower intestines.   Agrowastes could be utilized as a new probiotic carrier for enhanced gastrointestinal transit and during storage. This also reduces the amount of agrowastes accumulated.

Autoimmune diseases in a Danish cohort of 4,866 carriers of constitutional structural chromosomal rearrangements.

PubMed

Bache, Iben; Nielsen, Nete M; Rostgaard, Klaus; Tommerup, Niels; Frisch, Morten

2007-07-01

Constitutional structural chromosomal rearrangements (CSCRs) have facilitated the identification of genes associated with early-onset monogenic disorders and, more recently, genes associated with common and late-onset disorders. In an attempt to find genetic clues to their etiologies, we studied the risk of autoimmune diseases in a Danish cohort of CSCR carriers. We followed up 4,866 CSCR carriers over 71,230 person-years (1980 through 2004) for autoimmune diseases recorded in the Danish Hospital Discharge Register. Standardized incidence ratios (SIRs) and 95% confidence intervals (95% CIs) served as measures of the relative risk. To identify possible candidate loci for autoimmune diseases, the reported chromosomal breakpoints and deletions in CSCR carriers who developed autoimmune diseases were compared with previously suggested loci for these diseases. The overall risk of any autoimmune disease among CSCR carriers was inconspicuous (SIR 1.2 [95% CI 0.95-1.5]; n = 74 cases observed versus 61.3 expected), but carriers of rearrangements involving chromosomes 2, 19, and 21 were at significantly increased risk. For the specific autoimmune diseases studied, cohort members were at significantly increased risk of Dupuytren's contracture, pernicious anemia, and juvenile rheumatoid arthritis (JRA). Sixteen carriers who developed an autoimmune disease had a chromosomal breakpoint or deletion coinciding with a previously suggested locus, including deletions 18p11, 18q22, and 22q11 associated with JRA. CSCR carriers do not have a generalized predisposition to autoimmune diseases. However, we confirmed a number of reported susceptibility loci for JRA, and we suggest new susceptibility loci on chromosomes 5 and 11 for Dupuytren's contracture, and 19p13 as a possible shared susceptibility locus for a range of autoimmune diseases.

Single-cell-based system to monitor carrier driven cellular auxin homeostasis

PubMed Central

2013-01-01

Background Abundance and distribution of the plant hormone auxin play important roles in plant development. Besides other metabolic processes, various auxin carriers control the cellular level of active auxin and, hence, are major regulators of cellular auxin homeostasis. Despite the developmental importance of auxin transporters, a simple medium-to-high throughput approach to assess carrier activities is still missing. Here we show that carrier driven depletion of cellular auxin correlates with reduced nuclear auxin signaling in tobacco Bright Yellow-2 (BY-2) cell cultures. Results We developed an easy to use transient single-cell-based system to detect carrier activity. We use the relative changes in signaling output of the auxin responsive promoter element DR5 to indirectly visualize auxin carrier activity. The feasibility of the transient approach was demonstrated by pharmacological and genetic interference with auxin signaling and transport. As a proof of concept, we provide visual evidence that the prominent auxin transport proteins PIN-FORMED (PIN)2 and PIN5 regulate cellular auxin homeostasis at the plasma membrane and endoplasmic reticulum (ER), respectively. Our data suggest that PIN2 and PIN5 have different sensitivities to the auxin transport inhibitor 1-naphthylphthalamic acid (NPA). Also the putative PIN-LIKES (PILS) auxin carrier activity at the ER is insensitive to NPA in our system, indicating that NPA blocks intercellular, but not intracellular auxin transport. Conclusions This single-cell-based system is a useful tool by which the activity of putative auxin carriers, such as PINs, PILS and WALLS ARE THIN1 (WAT1), can be indirectly visualized in a medium-to-high throughput manner. Moreover, our single cell system might be useful to investigate also other hormonal signaling pathways, such as cytokinin. PMID:23379388

Plasma Soluble CD30 as a Possible Marker of Adult T-cell Leukemia in HTLV-1 Carriers: a Nested Case-Control Study.

PubMed

Takemoto, Shigeki; Iwanaga, Masako; Sagara, Yasuko; Watanabe, Toshiki

2015-01-01

Elevated levels of soluble CD30 (sCD30) are linked with various T-cell neoplasms. However, the relationship between sCD30 levels and the development of adult T-cell leukemia (ATL) in human T-cell leukemia virus type 1 (HTLV-1) carriers remains to be clarified. We here investigated whether plasma sCD30 is associated with risk of ATL in a nested case-control study within a cohort of HTLV-1 carriers. We compared sCD30 levels between 11 cases (i.e., HTLV-1 carriers who later progressed to ATL) and 22 age-, sex- and institution-matched control HTLV-1 carriers (i.e., those with no progression). The sCD30 concentration at baseline was significantly higher in cases than in controls (median 65.8, range 27.2-134.5 U/mL vs. median 22.2, range 8.4-63.1 U/mL, P=0.001). In the univariate logistic regression analysis, a higher sCD30 (≥30.2 U/mL) was significantly associated with ATL development (odds ratio 7.88 and the 95% confidence intervals 1.35-45.8, P = 0.02). Among cases, sCD30 concentration tended to increase at the time of diagnosis of aggressive-type ATL, but the concentration was stable in those developing the smoldering-type. This suggests that sCD30 may serve as a predictive marker for the onset of aggressive-type ATL in HTLV-1 carriers.

Development of a binary carrier system consisting polyethylene glycol 4000 - ethyl cellulose for ibuprofen solid dispersion

PubMed Central

Alagdar, Gada Sulaiman A.; Oo, May Kyaw; Sengupta, Pinaki; Mandal, Uttam Kumar; Jaffri, Julian Md.; Chatterjee, Bappaditya

2017-01-01

Background and Objective: One of the established strategies to improve solubility and dissolution rate of poorly water-soluble drugs is solid dispersion (SD). Polyethylene glycol (PEG) is used as common carrier despite its stability problem which may be overcome by the addition of hydrophobic polymer. The present research aimed to develop an SD formulation with ibuprofen, a poor water-soluble BCS Class II drug as active pharmaceutical ingredient (API) and PEG 4000-ethyl cellulose (EC) as binary carrier. Methods: Melt mixing SD method was employed using a ratio of API: binary carrier (1:3.5 w/w) (SDPE). Another SD was prepared using only PEG (SDP) as a carrier for comparative study. The developed formulation was evaluated using optical microscopy, scanning electron microscopy (SEM), determination of moisture content, differential scanning calorimetry (DSC), in vitro dissolution test, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and flow properties. Results: SEM and DSC indicated the conversion of crystalline ibuprofen to fine partly amorphous solid dispersion, which was responsible for the increase in dissolution rate of SD than a physical mixture. The release characteristics within 1 h from the higher to the lower value were the SDPE> SDP> physical mixture. Flow property evaluation using the angle of repose showed no difference between SD and PM. However, by Carr index and Hausner ratio, the flow properties of SDPE was excellent. Conclusion: The SD formulation with the PEG 4000-EC carrier can be effective to enhance in vitro dissolution of ibuprofen immediate release dosage form. PMID:29184827

A MEMS Multi-Cantilever Variable Capacitor On Metamaterial

DTIC Science & Technology

2009-03-26

tuning range [38]. 21 Bakri- Kassem and Mansour [39] have developed a parallel-plate variable capac- itor with carrier beams between the plates to...downwards, however, the carrier beams slightly bend down with the movable plate, still prevent- ing it from pulling-in. Bakri- Kassem and Mansour’s... Kassem and R. R. Mansour, “A high-tuning-range mems variable ca- pacitor using carrier beams,” Canadian Journal of Electrical and Computer En- gineering

Application of carrier testing to genetic counseling for X-linked agammaglobulinemia

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

Allen, R.C.; Nachtman, R.G.; Belmont, J.W.

Bruton X-linked agammaglobulinemia (XLA) is a phenotypically recessive genetic disorder of B lymphocyte development. Female carriers of XLA, although asymptomatic, have a characteristic B cell lineage-specific skewing of the pattern of X inactivation. Skewing apparently results from defective growth and maturation of B cell precursors bearing a mutant active X chromosome. In this study, carrier status was tested in 58 women from 22 families referred with a history of agammaglobulinemia. Primary carrier analysis to examine patterns of X inactivation in CD19[sup +] peripheral blood cells (B lymphocytes) was conducted using quantitative PCR at the androgen-receptor locus. Obligate carriers of XLAmore » demonstrated >95% skewing of X inactivation in peripheral blood CD19[sup +] cells but not in CD19[sup [minus

Frontiers, Opportunities and Challenges for a Hydrogen Economy

NASA Astrophysics Data System (ADS)

Turner, John

2015-03-01

Energy carriers are the staple for powering the society we live in. Coal, oil, natural gas, gasoline and diesel all carry energy in chemical bonds, used in almost all areas of our civilization. But these carriers have a limited-use lifetime on this planet. They are finite, contribute to climate change and carry significant geopolitical issues. If mankind is to maintain and grow our societies, new energy carriers must be developed and deployed into our energy infrastructure. Hydrogen is the simplest of all the energy carriers and when refined from water using renewable energies like solar and wind, represents a sustainable energy carrier, viable for millennia to come. This talk with discuss the challenges for sustainable production of hydrogen, along with the promise and possible pathways for implementing hydrogen into our energy infrastructure.

Cancer risks for BRCA1 and BRCA2 mutation carriers: results from prospective analysis of EMBRACE.

PubMed

Mavaddat, Nasim; Peock, Susan; Frost, Debra; Ellis, Steve; Platte, Radka; Fineberg, Elena; Evans, D Gareth; Izatt, Louise; Eeles, Rosalind A; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Cole, Trevor; Cook, Jackie; Brewer, Carole; Tischkowitz, Marc; Douglas, Fiona; Hodgson, Shirley; Walker, Lisa; Porteous, Mary E; Morrison, Patrick J; Side, Lucy E; Kennedy, M John; Houghton, Catherine; Donaldson, Alan; Rogers, Mark T; Dorkins, Huw; Miedzybrodzka, Zosia; Gregory, Helen; Eason, Jacqueline; Barwell, Julian; McCann, Emma; Murray, Alex; Antoniou, Antonis C; Easton, Douglas F

2013-06-05

Reliable estimates of cancer risk are critical for guiding management of BRCA1 and BRCA2 mutation carriers. The aims of this study were to derive penetrance estimates for breast cancer, ovarian cancer, and contralateral breast cancer in a prospective series of mutation carriers and to assess how these risks are modified by common breast cancer susceptibility alleles. Prospective cancer risks were estimated using a cohort of 978 BRCA1 and 909 BRCA2 carriers from the United Kingdom. Nine hundred eighty-eight women had no breast or ovarian cancer diagnosis at baseline, 1509 women were unaffected by ovarian cancer, and 651 had been diagnosed with unilateral breast cancer. Cumulative risks were obtained using Kaplan-Meier estimates. Associations between cancer risk and covariables of interest were evaluated using Cox regression. All statistical tests were two-sided. The average cumulative risks by age 70 years for BRCA1 carriers were estimated to be 60% (95% confidence interval [CI] = 44% to 75%) for breast cancer, 59% (95% CI = 43% to 76%) for ovarian cancer, and 83% (95% CI = 69% to 94%) for contralateral breast cancer. For BRCA2 carriers, the corresponding risks were 55% (95% CI = 41% to 70%) for breast cancer, 16.5% (95% CI = 7.5% to 34%) for ovarian cancer, and 62% (95% CI = 44% to 79.5%) for contralateral breast cancer. BRCA2 carriers in the highest tertile of risk, defined by the joint genotype distribution of seven single nucleotide polymorphisms associated with breast cancer risk, were at statistically significantly higher risk of developing breast cancer than those in the lowest tertile (hazard ratio = 4.1, 95% CI = 1.2 to 14.5; P = .02). Prospective risk estimates confirm that BRCA1 and BRCA2 carriers are at high risk of developing breast, ovarian, and contralateral breast cancer. Our results confirm findings from retrospective studies that common breast cancer susceptibility alleles in combination are predictive of breast cancer risk for BRCA2 carriers.

Development of environmentally conscious cleaning process for leadless chip carrier assemblies. Final report

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

Adams, B.E.

1995-04-01

A cross-functional team of process, product, quality, material, and design lab engineers was assembled to develop an environmentally friendly cleaning process for leadless chip carrier assemblies (LCCAs). Using flush and filter testing, Auger surface analysis, GC-Mass spectrophotometry, production yield results, and electrical testing results over an extended testing period, the team developed an aqueous cleaning process for LCCAs. The aqueous process replaced the Freon vapor degreasing/ultrasonic rinse process.

Amorphous Silica Based Nanomedicine with Safe Carrier Excretion and Enhanced Drug Efficacy

NASA Astrophysics Data System (ADS)

Zhang, Silu

With recent development of nanoscience and nanotechnology, a great amount of efforts have been devoted to nanomedicine development. Among various nanomaterials, silica nanoparticle (NP) is generally accepted as non-toxic, and can provide a versatile platform for drug loading. In addition, the surface of the silica NP is hydrophilic, being favorable for cellular uptake. Therefore, it is considered as one of the most promising candidates to serve as carriers for drugs. The present thesis mainly focuses on the design of silica based nanocarrier-drug systems, aiming at achieving safe nanocarrier excretion from the biological system and enhanced drug efficacy, which two are considered as most important issues in nanomedicine development. To address the safe carrier excretion issue, we have developed a special type of selfdecomposable SiO2-drug composite NPs. By creating a radial concentration gradient of drug in the NP, the drug release occurred simultaneously with the silica carrier decomposition. Such unique characteristic was different from the conventional dense SiO2-drug NP, in which drug was uniformly distributed and can hardly escape the carrier. We found that the controllable release of the drug was primarily determined by diffusion, which was caused by the radial drug concentration gradient in the NP. Escape of the drug molecules then triggered the silica carrier decomposition, which started from the center of the NP and eventually led to its complete fragmentation. The small size of the final carrier fragments enabled their easy excretion via renal systems. Apart from the feature of safe carrier excretion, we also found the controlled release of drugs contribute significantly to the drug efficacy enhancement. By loading an anticancer drug doxorubicin (Dox) to the decomposable SiO 2-methylene blue (MB) NPs, we achieved a self-decomposable SiO 2(MB)-Dox nanomedicine. The gradual escape of drug molecules from NPs and their enabled cytosolic release by optical switch, led to not only high but also stable drug concentration in cytosol within a sustained period. This resulted in enhanced drug efficacy, which is especially manifested in multidrug resistant (MDR) cancer cells, due to the fact that the NP-carrier drug can efficiently bypass the efflux mechanisms and increase drug availability. Together with its feature of spontaneous carrier decomposition and safe excretion, this type of nanomedicine's high drug efficacy highlights its potential for low dose anticancer drug treatment and reduced adverse effect to biological system, holding great promise for clinical translation. The enhanced drug efficacy by employing the self-decomposable silica nanocarrier is also demonstrated in photodynamic therapy (PDT). The loose and fragmentable features of the self-decomposable SiO2-photosensitizer (PS) NPs promoted the outdiffusion of the generated ROS, which resulted in a higher efficacy than that of dense SiO2-PS NPs. On the other hand, we also explored another nanocarrier configuration of Au nanorods decorated SiO2 NP, with PS drug embedded into dense SiO2 matrix. A different mechanism of drug efficacy enhancement was presented as the Au's surface plasmon resonance enhanced the ROS production. Although the drug efficacy of such SiO2(PS)-Au NPs was similar to that of self-decomposable SiO2-PS NPs, their potential for clinical applications was limited without the feature of safe carrier excretion. In summary, the self-decomposable SiO2 based NP developed is a most promising system to serve as safe and effective carriers for drugs. Together with the known biocompatibility of silica, the feature of controllable drug release and simultaneous carrier decomposition achieved in the self-decomposable SiO2-drug NPs make it ideal for a wide range of therapeutic applications.

HPMA Copolymer-Drug Conjugates with Controlled Tumor-Specific Drug Release.

PubMed

Chytil, Petr; Koziolová, Eva; Etrych, Tomáš; Ulbrich, Karel

2018-01-01

Over the past few decades, numerous polymer drug carrier systems are designed and synthesized, and their properties are evaluated. Many of these systems are based on water-soluble polymer carriers of low-molecular-weight drugs and compounds, e.g., cytostatic agents, anti-inflammatory drugs, or multidrug resistance inhibitors, all covalently bound to a carrier by a biodegradable spacer that enables controlled release of the active molecule to achieve the desired pharmacological effect. Among others, the synthetic polymer carriers based on N-(2-hydroxypropyl) methacrylamide (HPMA) copolymers are some of the most promising carriers for this purpose. This review focuses on advances in the development of HPMA copolymer carriers and their conjugates with anticancer drugs, with triggered drug activation in tumor tissue and especially in tumor cells. Specifically, this review highlights the improvements in polymer drug carrier design with respect to the structure of a spacer to influence controlled drug release and activation, and its impact on the drug pharmacokinetics, enhanced tumor uptake, cellular trafficking, and in vivo antitumor activity. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

On the Effects of a Spacecraft Subcarrier Unbalanced Modulator

NASA Technical Reports Server (NTRS)

Nguyen, Tien Manh

1993-01-01

This paper presents mathematical models with associated analysis of the deleterious effects which a spacecraft's subcarrier unbalanced modulator has on the performance of a phase-modulated residual carrier communications link. The undesired spectral components produced by the phase and amplitude imbalances in the subcarrier modulator can cause (1) potential interference to the carrier tracking and (2) degradation in the telemetry bit signal-to-noise ratio (SNR). A suitable model for the unbalanced modulator is developed and the threshold levels of undesired components that fall into the carrier tracking loop are determined. The distribution of the carrier phase error caused by the additive White Gaussian noise (AWGN) and undesired component at the residual RF carrier is derived for the limiting cases. Further, this paper analyses the telemetry bit signal-to-noise ratio degradations due to undesirable spectral components as well as the carrier tracking phase error induced by phase and amplitude imbalances. Numerical results which indicate the sensitivity of the carrier tracking loop and the telemetry symbol-error rate (SER) to various parameters of the models are also provided as a tool in the design of the subcarrier balanced modulator.

Fat Metabolism in Higher Plants

PubMed Central

Jacobson, Bruce S.; Jaworski, J. G.; Stumpf, P. K.

1974-01-01

Stearyl-acyl carrier protein desaturase (EC 1.14.99.6), present in the stroma fraction of spinach (Spinacia oleracea) chloroplasts, rapidly desaturated enzymatically prepared stearyl-acyl carrier protein to oleic acid. No other substrates were desaturated. In addition to stearyl-acyl carrier protein, reduced ferredoxin was an essential component of the system. The electron donor systems were either ascorbate, dichlorophenolindophenol, photosystem I and light, or NADPH and ferredoxin-NADP reductase. The desaturase was more active in extracts prepared from chloroplasts obtained from immature spinach leaves than from mature leaves. Stearyl-acyl carrier protein desaturase also occurs in soluble extracts of avocado (Persea americana Mill.) mesocarp and of developing safflower (Carthamus tinctorius) seeds. PMID:16658913

Polymeric anticancer drugs with pH-controlled activation.

PubMed

Ulbrich, Karel; Subr, Vladimír

2004-04-23

Use of macromolecular water-soluble carriers of anti-cancer drugs represents a promising approach to cancer therapy. Release of drugs from the carrier system is a prerequisite for therapeutic activity of most macromolecular anti-cancer conjugates. Incorporation of acid-sensitive spacers between the drug and carrier enables release of an active drug from the carrier in a tumor tissue, either in slightly acidic extracellular fluids or, after endocytosis, in endosomes or lysosomes of cancer cells. This paper reviews advances in development and study of properties of various acid-sensitive macromolecular drug delivery systems, starting from simple polymer-drug conjugates to ending with site-specific antibody-targeted polymer-drug conjugates.

Experimental program on nucleation and structure in undercooled melts

NASA Technical Reports Server (NTRS)

1982-01-01

Undercooling and structural refinements in droplets of molten metal levitated in an induction field and/or by dispersion in a fluid carrier were studied. Nickel base and lower melting point alloys levitated in molten carrier fluids are considered. The dispersion of molten alloy droplets in a high temperature fluid following the procedures developed by Perepezko and co-workers for lower melting point alloys; obtaining a similar dispersion by room temperature mechanical mixing of particles of the metal and solidified liquid carrier; and solidification of single relatively large droplets in a transparent fluid carrier, enabling high-speed temperature measurement of the recalescence and subsequent cooling behavior are described.

Multiphoton excitation and high-harmonics generation in topological insulator.

PubMed

Avetissian, H K; Avetissian, A K; Avchyan, B R; Mkrtchian, G F

2018-05-10

Multiphoton interaction of coherent electromagnetic radiation with 2D metallic carriers confined on the surface of the 3D topological insulator is considered. A microscopic theory describing the nonlinear interaction of a strong wave and metallic carriers with many-body Coulomb interaction is developed. The set of integrodifferential equations for the interband polarization and carrier occupation distribution is solved numerically. Multiphoton excitation of Fermi-Dirac sea of 2D massless carriers is considered for a THz pump wave. It is shown that in the moderately strong pump wave field along with multiphoton interband/intraband transitions the intense radiation of high harmonics takes place.

Multiphoton excitation and high-harmonics generation in topological insulator

NASA Astrophysics Data System (ADS)

Avetissian, H. K.; Avetissian, A. K.; Avchyan, B. R.; Mkrtchian, G. F.

2018-05-01

Multiphoton interaction of coherent electromagnetic radiation with 2D metallic carriers confined on the surface of the 3D topological insulator is considered. A microscopic theory describing the nonlinear interaction of a strong wave and metallic carriers with many-body Coulomb interaction is developed. The set of integrodifferential equations for the interband polarization and carrier occupation distribution is solved numerically. Multiphoton excitation of Fermi–Dirac sea of 2D massless carriers is considered for a THz pump wave. It is shown that in the moderately strong pump wave field along with multiphoton interband/intraband transitions the intense radiation of high harmonics takes place.

Comparison of Special Group Experiences in Establishing Independent Motor Carrier Businesses : Volume 2. Main Text.

DOT National Transportation Integrated Search

1979-08-01

The report examines the experiences and special problems of minority trucking firms. The firms are classified as unregulated local truckers, unregulated owner-operators, and regulated interstate common carriers. Random samples are developed for minor...

Preproghrelin Leu72Met polymorphism predicts a lower rate of developing renal dysfunction in type 2 diabetic nephropathy.

PubMed

Lee, Dae-Yeol; Kim, Sun-Young; Jo, Dae-Sun; Hwang, Pyoung Han; Kang, Kyung Pyo; Lee, Sik; Kim, Won; Park, Sung Kwang

2006-07-01

Ghrelin is a novel peptide hormone, which exerts somatotropic, orexigenic and adipogenic effects. Recent studies have shown that the preproghrelin Leu72Met polymorphism is associated with serum creatinine (Scr) concentration in type 2 diabetes; 72Met carriers exhibited lower Scr levels as compared with the 72Met non-carriers. We hypothesized that the preproghrelin Leu72Met polymorphism is associated with a lower rate of developing renal dysfunction in patients with type 2 diabetic nephropathy. The preproghrelin Leu72Met polymorphism was investigated using PCR techniques in 138 patients with diabetic nephropathy divided into two groups, one with normal renal function and the other with renal dysfunction. Determination of the frequency of the preproghrelin Leu72Met polymorphism was the main outcome measure. The frequency of the Leu72Met polymorphism in diabetic nephropathy was significantly lower in patients with renal dysfunction (15.9%, P < 0.01) than in patients with normal renal function (42.0%) or in the diabetes control group (40.6%). The Leu72Met polymorphism was also associated with serum total cholesterol levels in diabetic nephropathy patients with renal dysfunction; the 72Met carriers had lower total cholesterol levels than the 72Met non-carriers (P < 0.05). These data suggest that 72Met carrier status may be used as a marker predicting a lower chance of developing renal dysfunction in diabetic nephropathy.

Protein-protein conjugate nanoparticles for malaria antigen delivery and enhanced immunogenicity

PubMed Central

Scaria, Puthupparampil V.; Jones, David S.; Barnafo, Emma; Fischer, Elizabeth R.; Anderson, Charles; MacDonald, Nicholas J.; Lambert, Lynn; Rausch, Kelly M.; Narum, David L.

2017-01-01

Chemical conjugation of polysaccharide to carrier proteins has been a successful strategy to generate potent vaccines against bacterial pathogens. We developed a similar approach for poorly immunogenic malaria protein antigens. Our lead candidates in clinical trials are the malaria transmission blocking vaccine antigens, Pfs25 and Pfs230D1, individually conjugated to the carrier protein Exoprotein A (EPA) through thioether chemistry. These conjugates form nanoparticles that show enhanced immunogenicity compared to unconjugated antigens. In this study, we examined the broad applicability of this technology as a vaccine development platform, by comparing the immunogenicity of conjugates prepared by four different chemistries using different malaria antigens (PfCSP, Pfs25 and Pfs230D1), and carriers such as EPA, TT and CRM197. Several conjugates were synthesized using thioether, amide, ADH and glutaraldehyde chemistries, characterized for average molecular weight and molecular weight distribution, and evaluated in mice for humoral immunogenicity. Conjugates made with the different chemistries, or with different carriers, showed no significant difference in immunogenicity towards the conjugated antigens. Since particle size can influence immunogenicity, we tested conjugates with different average size in the range of 16–73 nm diameter, and observed greater immunogenicity of smaller particles, with significant differences between 16 and 73 nm particles. These results demonstrate the multiple options with respect to carriers and chemistries that are available for protein-protein conjugate vaccine development. PMID:29281708

Harmonious OCEAN?: Chinese Aircraft Carriers and Australia’s U.S. Alliance

DTIC Science & Technology

2010-03-10

St ra te gy R es ea rc h Pr oj ec t HARMONIOUS OCEAN?: CHINESE AIRCRAFT CARRIERS AND AUSTRALIA’S U.S. ALLIANCE BY COLONEL JOHN FREWEN...friendly countries designed to transport oil and other energy sources via roads and pipelines from the Indian Ocean into China.28 Carriers will be...attempts to build confidence and develop Chinese and American bilateral agreements have met with little success. None have delivered enduring or

The Development of Carriers and Adjuvants for Use with Peptides to Induce Mucosal and Systemic Immunity against Biologic Toxins

DTIC Science & Technology

1993-05-01

nature causes them to raturally form multimolecular, membranous vesicles (or vesicle fragments) (16-19). Like E. coli and salmonella outer membrane...to the varied nature of the peptides to be used, the optimal immunopotentiating regimen or carrier-adjuvant system may not be identical for each toxin...The carriers and adjuvants to be used will include natural proteins (proteosomes or other proteins). We further hypothesize that certain constructo

Unmanned Carrier-Based Aircraft System: Debate over Systems Role Led to Focus on Aerial Refueling

DTIC Science & Technology

2016-03-24

Unmanned Carrier-Based Aircraft System: Debate over System’s Role Led to Focus on Aerial Refueling Prior to February 2016, the Navy had planned to...award of the air system development contract by about 3 years from 2014 to 2017. In that report, we also found that knowledge the Navy had obtained...strike 1Pub. L. No. 113-66, § 213(d) (2013). 2GAO, Unmanned Carrier-Based Aircraft System: Navy Needs

Photo-conductive detection of continuous THz waves via manipulated ultrafast process in nanostructures

NASA Astrophysics Data System (ADS)

Moon, Kiwon; Lee, Eui Su; Lee, Il-Min; Park, Dong Woo; Park, Kyung Hyun

2018-01-01

Time-domain and frequency-domain terahertz (THz) spectroscopy systems often use materials fabricated with exotic and expensive methods that intentionally introduce defects to meet short carrier lifetime requirements. In this study, we demonstrate the development of a nano-photomixer that meets response speed requirements without using defect-incorporated, low-temperature-grown (LTG) semiconductors. Instead, we utilized a thin InGaAs layer grown on a semi-insulating InP substrate by metal-organic chemical vapor deposition (MOCVD) combined with nano-electrodes to manipulate local ultrafast photo-carrier dynamics via a carefully designed field-enhancement and plasmon effect. The developed nano-structured photomixer can detect continuous-wave THz radiation up to a frequency of 2 THz with a peak carrier collection efficiency of 5%, which is approximately 10 times better than the reference efficiency of 0.4%. The better efficiency results from the high carrier mobility of the MOCVD-grown InGaAs thin layer with the coincidence of near-field and plasmon-field distributions in the nano-structure. Our result not only provides a generally applicable methodology for manipulating ultrafast carrier dynamics by means of nano-photonic techniques to break the trade-off relation between the carrier lifetime and mobility in typical LTG semiconductors but also contributes to mass-producible photo-conductive THz detectors to facilitate the widespread application of THz technology.

FP core carrier technique: thermoplasticized gutta-percha root canal obturation technique using polypropylene core.

PubMed

Kato, Hiroshi; Nakagawa, Kan-Ichi

2010-01-01

Core carrier techniques are unique among the various root canal filling techniques for delivering and compacting gutta-percha in the prepared root canal system. Thermafil (TF), considered the major core carrier device, is provided as an obturator consisting of a master core coated with thermoplasticized gutta-percha. We have devised a thermoplasticized gutta-percha filling technique using a polypropylene core, FlexPoint® NEO (FP), which was developed as a canal filling material that can be sterilized in an autoclave. Therefore, FP can be coated onto thermoplasticized gutta-percha and inserted into the prepared canal as a core carrier. The FP core carrier technique offers many advantages over the TF system: the core can be tested in the root canal and verified radiographically; the core can be adjusted to fit and surplus material easily removed; furthermore the core can be easily removed for retreatment. The clinical procedure of the FP core carrier technique is simple, and similar that with the TF system. Thermoplasticized gutta-percha in a syringe is heated in an oven and extruded onto the FP core carrier after a trial insertion. The FP core carrier is inserted into the root canal to the working length. Excess FP is then removed with a red-hot plastic instrument at the orifice of the root canal. The FP core carrier technique incorporates the clinical advantages of the existing TF system while minimizing the disadvantages. Hence the FP core carrier technique is very useful in clinical practice. This paper describes the FP core carrier technique as a new core based method.

How does genetic risk information for Lynch syndrome translate to risk management behaviours?

PubMed

Steel, Emma; Robbins, Andrew; Jenkins, Mark; Flander, Louisa; Gaff, Clara; Keogh, Louise

2017-01-01

There is limited research on why some individuals who have undergone predictive genetic testing for Lynch syndrome do not adhere to screening recommendations. This study aimed to explore qualitatively how Lynch syndrome non-carriers and carriers translate genetic risk information and advice to decisions about risk managment behaviours in the Australian healthcare system. Participants of the Australasian Colorectal Cancer Family Registry who had undergone predictive genetic testing for Lynch syndrome were interviewed on their risk management behaviours. Transcripts were analysed thematically using a comparative coding analysis. Thirty-three people were interviewed. Of the non-carriers ( n  = 16), 2 reported having apparently unnecessary colonoscopies, and 6 were unsure about what population-based colorectal cancer screening entails. Of the carriers ( n  = 17), 2 reported they had not had regular colonoscopies, and spoke about their discomfort with the screening process and a lack of faith in the procedure's ability to reduce their risk of developing colorectal cancer. Of the female carriers ( n  = 9), 2 could not recall being informed about the associated risk of gynaecological cancers. Non-carriers and female carriers of Lynch syndrome could benefit from further clarity and advice about appropriate risk management options. For those carriers who did not adhere to colonoscopy screening, a lack of faith in both genetic test results and screening were evident. It is essential that consistent advice is offered to both carriers and non-carriers of Lynch syndrome.

Visual Function in Carriers of X-linked Retinitis Pigmentosa

PubMed Central

Comander, Jason; Weigel-DiFranco, Carol; Sandberg, Michael A.; Berson, Eliot L.

2015-01-01

Purpose To determine the frequency and severity of visual function loss in female carriers of X-linked retinitis pigmentosa (XLRP). Design Case series. Participants XLRP carriers with cross-sectional data (n = 242) and longitudinal data (n = 34, median follow-up: 16 years, follow-up range: 3–37 years). Half of the carriers were from RPGR- or RP2-genotyped families. Methods Retrospective medical records review. Main Outcome Measures Visual acuities, visual field areas, final dark adaptation thresholds, and full-field ERGs to 0.5 Hz and 30 Hz flashes. Results In genotyped families, 40% of carriers showed a baseline abnormality on at least one of the three psychophysical tests. There was a wide range of function among carriers; for example 3 of 121 (2%) of genotyped carriers were legally blind due to poor visual acuity, some as young as 35 years of age. Visual fields were less affected than visual acuity. In all carriers, the average ERG amplitude to 30 Hz flashes was about 50% of normal, and the average exponential rate of amplitude loss over time was half that of XLRP males (3.7%/year vs 7.4%/year, respectively). Among obligate carriers with affected fathers and/or sons, 53 of 55 (96%) had abnormal baseline ERGs. Some carriers who initially had completely normal fundi in both eyes went on to develop moderately decreased vision, though not legal blindness. Among carriers with RPGR mutations, those with mutations in ORF15, compared to those in exons 1–14, had worse final dark adaptation thresholds and lower 0.5 Hz and 30 Hz ERG amplitudes. Conclusions Most carriers of XLRP had mildly or moderately reduced visual function but rarely became legally blind. In most cases, obligate carriers could be identified by ERG testing. Carriers of RPGR ORF15 mutations tended to have worse visual function than carriers of RPGR exon 1–14 mutations. Since XLRP carrier ERG amplitudes and decay rates over time were on average half of those of affected males, these observations were consistent with the Lyon hypothesis of random X-inactivation. PMID:26143542

Pravastatin chitosan nanogels-loaded erythrocytes as a new delivery strategy for targeting liver cancer.

PubMed

Harisa, Gamaleldin I; Badran, Mohamed M; AlQahtani, Saeed A; Alanazi, Fars K; Attia, Sabry M

2016-01-01

Chitosan nanogels (CNG) are developed as one of the most promising carriers for cancer targeting. However, these carriers are rapidly eliminated from circulation by reticuloendothelial system (RES), which limits their application. Therefore, erythrocytes (ER) loaded CNG as multifunctional carrier may overcome the massive elimination of nanocarriers by RES. In this study, erythrocytes loaded pravastatin-chitosan nanogels (PR-CNG-ER) were utilized as a novel drug carrier to target liver cancer. Thus, PR-CNG formula was developed in nanosize, with good entrapment efficiency, drug loading and sustained release over 48 h. Then, PR-CNG loaded into ER were prepared by hypotonic preswelling technique. The resulting PR-CNG-ER showed 36.85% of entrapment efficiency, 66.82% of cell recovery and release consistent to that of hemoglobin over 48 h. Moreover, PR-CNG-ER exhibited negative zeta potential, increasing of hemolysis percent, marked phosphatidylserine exposure and stomatocytes shape compared to control unloaded erythrocytes. PR-CNG-ER reduced cells viability of HepG2 cells line by 28% compared to unloaded erythrocytes (UER). These results concluded that PR-CNG-ER are promising drug carriers to target liver cancer.

Pravastatin chitosan nanogels-loaded erythrocytes as a new delivery strategy for targeting liver cancer

PubMed Central

Harisa, Gamaleldin I.; Badran, Mohamed M.; AlQahtani, Saeed A.; Alanazi, Fars K.; Attia, Sabry M.

2015-01-01

Chitosan nanogels (CNG) are developed as one of the most promising carriers for cancer targeting. However, these carriers are rapidly eliminated from circulation by reticuloendothelial system (RES), which limits their application. Therefore, erythrocytes (ER) loaded CNG as multifunctional carrier may overcome the massive elimination of nanocarriers by RES. In this study, erythrocytes loaded pravastatin–chitosan nanogels (PR–CNG–ER) were utilized as a novel drug carrier to target liver cancer. Thus, PR–CNG formula was developed in nanosize, with good entrapment efficiency, drug loading and sustained release over 48 h. Then, PR–CNG loaded into ER were prepared by hypotonic preswelling technique. The resulting PR–CNG–ER showed 36.85% of entrapment efficiency, 66.82% of cell recovery and release consistent to that of hemoglobin over 48 h. Moreover, PR–CNG–ER exhibited negative zeta potential, increasing of hemolysis percent, marked phosphatidylserine exposure and stomatocytes shape compared to control unloaded erythrocytes. PR–CNG–ER reduced cells viability of HepG2 cells line by 28% compared to unloaded erythrocytes (UER). These results concluded that PR–CNG–ER are promising drug carriers to target liver cancer. PMID:26903771

Charge carrier coherence and Hall effect in organic semiconductors

DOE PAGES

Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

2016-03-30

Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force actingmore » on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Lastly, our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.« less

Preimplantation genetic haplotyping a new application for diagnosis of translocation carrier's embryos- preliminary observations of two robertsonian translocation carrier families.

PubMed

Shamash, Jana; Rienstein, Shlomit; Wolf-Reznik, Haike; Pras, Elon; Dekel, Michal; Litmanovitch, Talia; Brengauz, Masha; Goldman, Boleslav; Yonath, Hagith; Dor, Jehoshua; Levron, Jacob; Aviram-Goldring, Ayala

2011-01-01

Preimplantation genetic diagnosis using fluorescence in-situ hybridization (PGD-FISH) is currently the most common reproductive solution for translocation carriers. However, this technique usually does not differentiate between embryos carrying the balanced form of the translocation and those carrying the homologous normal chromosomes. We developed a new application of preimplantation genetic haplotyping (PGH) that can identify and distinguish between all forms of the translocation status in cleavage stage embryos prior to implantation. Polymorphic markers were used to identify and differentiate between the alleles that carry the translocation and those that are the normal homologous chromosomes. Embryos from two families of robertsonian translocation carriers were successfully analyzed using polymorphic markers haplotyping. Our preliminary results indicate that the PGH is capable of distinguishing between normal, balanced and unbalanced translocation carrier embryos. This method will improve PGD and will enable translocation carriers to avoid transmission of the translocation and the associated medical complications to offspring.

Charge carrier coherence and Hall effect in organic semiconductors

PubMed Central

Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

2016-01-01

Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor. PMID:27025354

Near-field control and imaging of free charge carrier variations in GaN nanowires

NASA Astrophysics Data System (ADS)

Berweger, Samuel; Blanchard, Paul T.; Brubaker, Matt D.; Coakley, Kevin J.; Sanford, Norman A.; Wallis, Thomas M.; Bertness, Kris A.; Kabos, Pavel

2016-02-01

Despite their uniform crystallinity, the shape and faceting of semiconducting nanowires (NWs) can give rise to variations in structure and associated electronic properties. Here, we develop a hybrid scanning probe-based methodology to investigate local variations in electronic structure across individual n-doped GaN NWs integrated into a transistor device. We perform scanning microwave microscopy (SMM), which we combine with scanning gate microscopy to determine the free-carrier SMM signal contribution and image local charge carrier density variations. In particular, we find significant variations in free carriers across NWs, with a higher carrier density at the wire facets. By increasing the local carrier density through tip-gating, we find that the tip injects current into the NW with strongly localized current when positioned over the wire vertices. These results suggest that the strong variations in electronic properties observed within NWs have significant implications for device design and may lead to new paths to optimization.

Communication about carrier testing within hemophilia A families.

PubMed

Sorenson, James R; Jennings-Grant, Tracey; Newman, Jamie

2003-05-15

Genetic diseases are family diseases. Although there is considerable research on how individuals decide to have genetic testing and their individual reactions to testing, there is limited research on the familial context of genetic testing. In the present study, we focus on three aspects of the family context of genetic testing for hemophilia A carrier status among women at risk to be carriers. We look at the extent to which there was discussion of carrier testing for hemophilia before we offered DNA-based carrier testing to these at-risk women; with which family members these tested women communicated the results of their carrier testing; and concerns these women had about communicating their carrier test results with relatives, including their children. Data suggest that members of families with hemophilia discussed carrier testing prior to study participation, that the communication of testing information within families was selective, not universal, largely following gender lines for this X-linked disorder, and that there was limited concern about communicating carrier status information to children and other relatives. These data reinforce observations that families are social systems, and within these systems information is selectively communicated. A more complete understanding of how families communicate genetic test information will enable providers to develop more effective means of assisting individuals in handling the familial communication aspects of genetic testing. Copyright 2002 Wiley-Liss, Inc.

Use of Prior Vaccinations for the Development of New Vaccines

NASA Astrophysics Data System (ADS)

Etlinger, H. M.; Gillessen, D.; Lahm, H.-W.; Matile, H.; Schonfeld, H.-J.; Trzeciak, A.

1990-07-01

There is currently a need for vaccine development to improve the immunogenicity of protective epitopes, which themselves are often poorly immunogenic. Although the immunogenicity of these epitopes can be enhanced by linking them to highly immunogenic carriers, such carriers derived from current vaccines have not proven to be generally effective. One reason may be related to epitope-specific suppression, in which prior vaccination with a protein can inhibit the antibody response to new epitopes linked to the protein. To circumvent such inhibition, a peptide from tetanus toxoid was identified that, when linked to a B cell epitope and injected into tetanus toxoid-primed recipients, retained sequences for carrier but not suppressor function. The antibody response to the B cell epitope was enhanced. This may be a general method for taking advantage of previous vaccinations in the development of new vaccines.

Biodegradable nano-micro carrier systems for sustained pulmonary drug delivery: (I) Self-assembled nanoparticles encapsulated in respirable/swellable semi-IPN microspheres

PubMed Central

El-Sherbiny, I. M.; Smyth, H. D. C.

2012-01-01

Design of appropriate inhaled carriers with adequate aerodynamic properties, drug release, biodegradation and evasion of macrophage uptake is a major challenge for controlled release pulmonary drug delivery. In this study, PEG graft copolymerized onto N-phthaloyl chitosan (NPHCs) was synthesized then characterized using FTIR, EA, DSC and 2D-XRD. The resulting PEG-g-NPHCs copolymers were self-assembled into drug loaded nanoparticles and encapsulated in respirable/swellable sodium alginate semi-IPN hydrogel microspheres as novel biodegradable carriers for controlled release pulmonary drug delivery. The developed nano-/microspheres carrier systems were formed via spray drying followed by ionotropic crosslinking in mild aqueous medium. The size of the developed self-assembled nanoparticles and the microspheres was measured using dynamic light scattering and laser diffraction, respectively. Morphology, moisture content, in-vitro biodegradation and dynamic swelling studies were also investigated for the developed carriers. A model protein was entrapped and the in-vitro release profiles were determined in PBS, pH 7.4 at 37°C. A dry powder aerosolization study was conducted using a Next Generation Impactor (NGI). The developed microspheres had suitable aerodynamic diameters (1.02–2.63 μm) and an excellent fine particle fraction, FPF of 31.52%. The microspheres showed also a very fast initial swelling within the first 2 min and started to enzymatically degrade within the first two hours. Moreover, the microspheres entrapped up 90% of the model drug and showed promising in-vitro sustained release profiles as compared to the control formulation. PMID:20580794

Development of a solidified self-microemulsifying drug delivery system (S-SMEDDS) for atorvastatin calcium with improved dissolution and bioavailability.

PubMed

Yeom, Dong Woo; Son, Ho Yong; Kim, Jin Han; Kim, Sung Rae; Lee, Sang Gon; Song, She Hyon; Chae, Bo Ram; Choi, Young Wook

2016-06-15

To improve the dissolution and oral bioavailability (BA) of atorvastatin calcium (ATV), we previously introduced an optimized self-microemulsifying drug delivery system (SMEDDS) using Capmul(®) MCM (oil), Tween(®) 20 (surfactant), and tetraglycol (cosurfactant). In this study, various solid carriers were employed to develop a solidified SMEDDS (S-SMEDDS): mannitol (M) and lactose (L) as water-soluble carriers, and Sylysia(®) 350 (S) and Aerosil(®) 200 (A) as water-insoluble carriers. Maximum solidifying capacities (SCmax) of water-insoluble carriers were significantly greater than those of water-soluble carriers were. The resultant powders were free flowing with an angle of repose <40° and Carr's index 5-20%, regardless of the solid carrier types. S-SMEDDS with mannitol (S(M)-SMEDDS) or lactose (S(L)-SMEDDS) had a smaller droplet size and greater dissolution than S-SMEDDS with Sylysia(®) 350 (S(S)-SMEDDS) or Aerosil(®) 200 (S(A)-SMEDDS). Following oral administration of various formulations to rats at a dose equivalent to 25mg/kg of ATV, plasma drug levels were measured by LC-MS/MS. The relative BAs (RBAs) of SMEDDS, S(M)-SMEDDS, and S(S)-SMEDDS were 345%, 216%, and 160%, respectively, compared to that of ATV suspension. Additionally, at a reduced dose of ATV equivalent to 5mg/kg, the RBAs of S(M)-SMEDDS and S(S)-SMEDDS compared to that of SMEDDS were 101% and 65%, respectively. These results suggest that S(M)-SEMDDS offers great potential for the development of solid dosage forms with improved oral absorption of drugs with poor water solubility. Copyright © 2016 Elsevier B.V. All rights reserved.

A new approach to harmonic elimination based on a real-time comparison method

NASA Astrophysics Data System (ADS)

Gourisetti, Sri Nikhil Gupta

Undesired harmonics are responsible for noise in a transmission channel, power loss in power electronics and in motor control. Selective Harmonic Elimination (SHE) is a well-known method used to eliminate or suppress the unwanted harmonics between the fundamental and the carrier frequency harmonic/component. But SHE bears the disadvantage of its incapability to use in real-time applications. A novel reference-carrier comparative method has been developed which can be used to generate an SPWM signal to apply in real-time systems. A modified carrier signal is designed and tested for different carrier frequencies based on the generated SPWM FFT. The carrier signal may change for different fundamental to carrier ratio that leads to solving the equations each time. An analysis to find all possible solutions for a particular carrier frequency and fundamental amplitude is performed and found. This proves that there is no one global maxima instead several local maximas exists for a particular condition set that makes this method less sensitive. Additionally, an attempt to find a universal solution that is valid for any carrier signal with predefined fundamental amplitude is performed. A uniform distribution Monte-Carlo sensitivity analysis is performed to measure the window i.e., best and worst possible solutions. The simulations are performed using MATLAB and are justified with experimental results.

Research and Applications Modules (RAM). Phase B study: Executive summary

NASA Technical Reports Server (NTRS)

1972-01-01

The design, development, and characteristics of the Research and Applications Module (RAM) system is discussed. The RAM system is a family of payload carriers that can be delivered to and retrieved from low earth orbit by the space shuttle. The RAM payload carriers are used to support diverse technological and scientific investigations. The NASA study objectives, the relationship of the RAM payload carriers to other systems in the orbital space program, and recommendations for additional effort are presented.

Commercial motor vehicles : effectiveness of actions being taken to improve motor carrier safety is unknown

DOT National Transportation Integrated Search

2000-07-01

The motor carrier administration has developed an overall strategy for improving the safety of commercial motor vehicles (trucks and buses). This strategy, called the Safety Action Plan, covers the years 2000 through 2003 and contains 47 initiatives ...

The effects of safety practice, technology adoption, and firm characteristics on motor carrier safety

DOT National Transportation Integrated Search

2004-01-01

The theory of the firm suggests that firms should maximize profit by investing in safety until : marginal cost is equal to the marginal benefit. This paper addresses motor carrier safety from the : perspective of the firm, developing the theoretical ...

Cell viability of mycorrhiza helper bacteria solid inoculant in different carrier material

NASA Astrophysics Data System (ADS)

Asyiah, Iis Nur; Hindersah, Reginawanti; Harni, Rita

2018-02-01

Roots of food crops are colonized by nonpathogenic mycorrhizal fungi which show natural ability to control plant pathogen. Mycorrhizal establishment in plant roots is affected by rhizobacteria, known as mycorrhiza helper bacteria (MHB), which has synergetic effects on mycorrhizal associations. Laboratory experiment has been conducted to assess the best carrier material to develop well-qualified MHB of Pseudomonas diminuta and Bacillus subtilis solid inoculant. Carrier materials were 100 mesh organic matter of agricultural waste. Different spore concentration of both bacterial liquid inoculants were grown on three kinds of 100-mesh organic matter and stored at room temperature up to 90 days. Cell viability of both MHB were counted by serial dilution plate method by using specific medium. The results showed that sugar cane baggase ash was the best carrier material to maintain cell viability for both MHB. However, the population of Pseudomonas diminuta and Bacillus subtilis in sugar cane baggase ash were slightly decreased after 90 days. The use of sugarcane baggase ash for solid MHB inoculant development could be suggested.

Design and Efficacy of Nanogels Formulations for Intranasal Administration.

PubMed

Aderibigbe, Blessing A; Naki, Tobeka

2018-05-23

Nanogels are drug delivery systems that can bypass the blood-brain barrier and deliver drugs to the desired site when administered intranasally. They have been used as a drug delivery platform for the management of brain diseases such as Alzheimer disease, migraine, schizophrenia and depression. nanogels have also been developed as vaccine carriers for the protection of bacterial infections such as influenza, meningitis, pneumonia and as veterinary vaccine carriers for the protection of animals from encephalomyelitis and mouth to foot disease. It has been developed as vaccine carriers for the prevention of lifestyle disease such as obesity. Intranasal administration of therapeutics using nanogels for the management of brain diseases revealed that the drug transportation was via the olfactory nerve pathway resulting in rapid drug delivery to the brain with excellent neuroprotective effect. The application of nanogels as vaccine carriers also induced significant responses associated with protective immunity against selected bacterial and viral infections. This review provides a detailed information on the enhanced therapeutic effects, mechanisms and biological efficacy of nanogels for intranasal administration.

Biocompatible and biodegradable fibrinogen microspheres for tumor-targeted doxorubicin delivery

PubMed Central

Joo, Jae Yeon; Park, Gil Yong; An, Seong Soo A

2015-01-01

In the development of effective drug delivery carriers, many researchers have focused on the usage of nontoxic and biocompatible materials and surface modification with targeting molecules for tumor-specific drug delivery. Fibrinogen (Fbg), an abundant glycoprotein in plasma, could be a potential candidate for developing drug carriers because of its biocompatibility and tumor-targeting property via arginine–glycine–aspartate (RGD) peptide sequences. Doxorubicin (DOX), a chemotherapeutic agent, was covalently conjugated to Fbg, and the microspheres were prepared. Acid-labile and non-cleavable linkers were used for the conjugation of DOX to Fbg, resulting in an acid-triggered drug release under a mild acidic condition and a slow-controlled drug release, respectively. In vitro cytotoxicity tests confirmed low cytotoxicity in normal cells and high antitumor effect toward cancer cells. In addition, it was discovered that a longer linker could make the binding of cells to Fbg drug carriers easier. Therefore, DOX–linker–Fbg microspheres could be a suitable drug carrier for safer and effective drug delivery. PMID:26366073

Mechanism of the free charge carrier generation in the dielectric breakdown

NASA Astrophysics Data System (ADS)

Rahim, N. A. A.; Ranom, R.; Zainuddin, H.

2017-12-01

Many studies have been conducted to investigate the effect of environmental, mechanical and electrical stresses on insulator. However, studies on physical process of discharge phenomenon, leading to the breakdown of the insulator surface are lacking and difficult to comprehend. Therefore, this paper analysed charge carrier generation mechanism that can cause free charge carrier generation, leading toward surface discharge development. Besides, this paper developed a model of surface discharge based on the charge generation mechanism on the outdoor insulator. Nernst’s Planck theory was used in order to model the behaviour of the charge carriers while Poisson’s equation was used to determine the distribution of electric field on insulator surface. In the modelling of surface discharge on the outdoor insulator, electric field dependent molecular ionization was used as the charge generation mechanism. A mathematical model of the surface discharge was solved using method of line technique (MOL). The result from the mathematical model showed that the behaviour of net space charge density was correlated with the electric field distribution.

Preparation and application of functionalized nano drug carriers.

PubMed

Gong, Rudong; Chen, Gaimin

2016-05-01

Targeting at category memory characteristics and preparation methods of functionalized nano drugs, preparation technology of functionalized nano drug carriers is studied, and then important role of functionalized nano drug carrier in preparation of medicine is studied. Carry out the relevant literature search with computer, change limited language in the paper to Chinese and necessarily remove repetitive studies. After first review of 1260 retrieved literature, it can be found that nano drug is with accurate quantity, relatively good targeting, specificity and absorbency. Necessary research of nano drug carriers can prevent and treat disease to a certain extent. Preparation of functionalized nanocarrier is simple and convenient, which can improve frequency of use of nano preparation technology and provide better development space for medical use. Therefore, nanocarriers should be combined with drugs with relatively strong specificity in clinics, in order to be able to conduct effective research on nanometer intelligent drug, effectively promote long-term development of nano biotechnology, and then provide favorable, reliable basis for clinical diagnosis and treatment.

[Drug delivery systems using nano-sized drug carriers].

PubMed

Nakayama, Masamichi; Okano, Teruo

2005-07-01

Nanotechnology has attracted great attention all over the world in recent several years and has led to the establishment of the novel technical field of "nanomedicine" through collaboration with advanced medical technology. Particularly, site-specific drug targeting using particle drug carrier systems has made substantial progress and been actively developed. This review explains the essential factors (size and chemical character) of drug carriers to allow long circulation in the bloodstream avoiding the reticuloendothelial system, and shows the present status and future perspective of several types of nano-carrier systems (water-soluble polymer, liposome and polymeric micelle). We also introduce the novel concept of multi-targeting system (combination of two or more targeting methodologies) for ideal drug therapies.

Nanogel Carrier Design for Targeted Drug Delivery

PubMed Central

Eckmann, D. M.; Composto, R. J.; Tsourkas, A.; Muzykantov, V. R.

2014-01-01

Polymer-based nanogel formulations offer features attractive for drug delivery, including ease of synthesis, controllable swelling and viscoelasticity as well as drug loading and release characteristics, passive and active targeting, and the ability to formulate nanogel carriers that can respond to biological stimuli. These unique features and low toxicity make the nanogels a favorable option for vascular drug targeting. In this review, we address key chemical and biological aspects of nanogel drug carrier design. In particular, we highlight published studies of nanogel design, descriptions of nanogel functional characteristics and their behavior in biological models. These studies form a compendium of information that supports the scientific and clinical rationale for development of this carrier for targeted therapeutic interventions. PMID:25485112

Design, manufacturing and testing of a portable vaccine carrier box employing thermoelectric module and heat pipe.

PubMed

Putra, N

2009-01-01

Vaccination is a highly effective method and a cheap tool for preventing certain infectious diseases. Routine immunization programs protect most of the world's children from diseases that claim millions of lives each year. There are many practical problems impeding vaccine delivery, especially to maintain the cold chain system, which is the means for storing and transporting vaccines in a potent state from the manufacturer to the person being immunized at a temperature of 2-8 degrees C. The development of the solid state thermoelectric cooling system has permitted newly developed packages that are capable of meeting many requirements and applications where environmental concern, size, weight, performance and noise are an issue. This paper describes the development of a vaccine carrier box. A combination of a thermoelectric module and a heat pipe is used for the cooling system. The position of the heat pipe as a heat sink on the hot side of the thermoelectric module will enhance the thermoelectric performance. The minimum temperature in the cabin of the vaccine carrier box reached -10 degrees C, which indicates that the design of the vaccine carrier box can maintain the vaccine at desired temperatures.

Injectable Nanocomposite Analgesic Delivery System for Musculoskeletal Pain Management.

PubMed

Khanal, Manakamana; Gohil, Shalini V; Kuyinu, Emmanuel; Kan, Ho-Man; Knight, Brittany E; Baumbauer, Kyle M; Lo, Kevin W-H; Walker, Joseph; Laurencin, Cato T; Nair, Lakshmi S

2018-05-24

Musculoskeletal pain is a major health issue which results from surgical procedures (i.e. total knee and/ or hip replacements and rotator cuff repairs), as well as from non-surgical conditions (i.e. sympathetically-mediated pain syndrome and occipital neuralgia). Local anesthetics, opioids or corticosteroids are currently used for the pain management of musculoskeletal conditions. Even though local anesthetics are highly preferred, the need for multiple administration presents significant disadvantages. Development of unique delivery systems that can deliver local anesthetics at the injection site for prolonged time could significantly enhance the therapeutic efficacy and patient comfort. The goal of the present study is to evaluate the efficacy of an injectable local anesthetic nanocomposite carrier to provide sustained analgesic effect. The nanocomposite carrier was developed by encapsulating ropivacaine, a local anesthetic, in lipid nanocapsules (LNC-Rop), and incorporating the nanocapsules in enzymatically crosslinked glycol chitosan (0.3GC) hydrogels. Cryo Scanning Electron Microscopic (Cryo SEM) images showed the ability to distribute the LNCs within the hydrogel without adversely affecting their morphology. The study demonstrated the feasibility to achieve sustained release of lipophilic molecules from the nanocomposite carrier in vitro and in vivo. A rat chronic constriction injury (CCI) pain model was used to evaluate the efficacy of the nanocomposite carrier using thermal paw withdrawal latency (TWL). The nanocomposite carriers loaded with ropivacaine and dexamethasone showed significant improvement in pain response compared to the control groups for at least 7 days. The study demonstrated the clinical potential of these nanocomposite carriers for post-operative and neuropathic pain. Acute or chronic pain associated with musculoskeletal conditions is considered a major health issue, with healthcare costs totaling several billion dollars. The opioid crisis presents a pressing clinical need to develop alternative and effective approaches to treat musculoskeletal pain. The goal of this study was to develop a long-acting injectable anesthetic formulation which can sustain a local anesthetic effect for a prolonged time. This in turn could increase the quality of life and rehabilitation outcome of patients, and decrease opioid consumption. The developed injectable nanocomposite demonstrated the feasibility to achieve prolonged pain relief in a rat chronic constriction injury (CCI) model. Copyright © 2018. Published by Elsevier Ltd.

Thermally targeted delivery of chemotherapeutics and anti-cancer peptides by elastin-like polypeptide.

PubMed

Raucher, Drazen; Massodi, Iqbal; Bidwell, Gene L

2008-03-01

Current chemotherapy treatment of solid tumors is limited due to a lack of specific delivery of the drugs to the tumor, leading to systemic toxicity. Therefore, it is necessary to develop targeted cancer therapies and tumor-targeted drug carriers. The authors review the development of elastin-like polypeptide (ELP) as a potential carrier for thermally targeted delivery of therapeutics. The authors searched Medline for articles concerning the application of ELP as a drug delivery vector for small molecule drugs and therapeutic peptides. ELP has been demonstrated to be a promising thermally targeted carrier. Further examination of the in vivo biodistribution and efficacy will provide the necessary data to advance ELP technology toward the ultimate goal of human therapeutics.

Suppression of compensating native defect formation during semiconductor processing via excess carriers

NASA Astrophysics Data System (ADS)

Alberi, K.; Scarpulla, M. A.

2016-06-01

In many semiconductors, compensating defects set doping limits, decrease carrier mobility, and reduce minority carrier lifetime thus limiting their utility in devices. Native defects are often responsible. Suppressing the concentrations of compensating defects during processing close to thermal equilibrium is difficult because formation enthalpies are lowered as the Fermi level moves towards the majority band edge. Excess carriers, introduced for example by photogeneration, modify the formation enthalpy of semiconductor defects and thus can be harnessed during crystal growth or annealing to suppress defect populations. Herein we develop a rigorous and general model for defect formation in the presence of steady-state excess carrier concentrations by combining the standard quasi-chemical formalism with a detailed-balance description that is applicable for any defect state in the bandgap. Considering the quasi-Fermi levels as chemical potentials, we demonstrate that increasing the minority carrier concentration increases the formation enthalpy for typical compensating centers, thus suppressing their formation. This effect is illustrated for the specific example of GaSb. While our treatment is generalized for excess carrier injection or generation in semiconductors by any means, we provide a set of guidelines for applying the concept in photoassisted physical vapor deposition.

Performance Characterization of RaPToRS Systems

NASA Astrophysics Data System (ADS)

Shibata, K.; Krieger, M.; Fallica, J.; Henchen, R.; Pogozelski, E.; Padalino, S.; SUNY Geneseo Collaboration; LaboratoryLaser Energetics at University of Rochester Collaboration

2011-10-01

The Rapid Pneumatic Transport of Radioactive Samples (RaPToRS) system can quickly and efficiently move radioactive materials from their activation site to a counting station. Facilities such as the NIF and LLE are considering these systems while NRL is currently using one. The system is essentially a 10 cm diameter pneumatic tube with a cylindrical sample carrier. The performance of the system depends on many factors, including the mass of the carrier, length of the tube, angle and difference in height of the tube's endpoints, the carrier's physical design, and the number, type, and distribution of blowers attached to the tube. These factors have been systematically examined to develop the fastest and most reliable system. The most significant factors are the mass and the vertical travel of the carrier. When the carrier mass is low, moving air supports the carrier in the tube, resulting in low friction. The terminal velocity ranges from 13.5 to 2.5 m/s for masses varying from 1 kg to 3 kg. Using a single 1100 W blower, the initial force exerted on the carrier was 11.3 N. This work was supported in part by the US Department of Energy through the LLE.

Suppression of compensating native defect formation during semiconductor processing via excess carriers

DOE PAGES

Alberi, Kirstin; Scarpulla, M. A.

2016-06-21

In many semiconductors, compensating defects set doping limits, decrease carrier mobility, and reduce minority carrier lifetime thus limiting their utility in devices. Native defects are often responsible. Suppressing the concentrations of compensating defects during processing close to thermal equilibrium is difficult because formation enthalpies are lowered as the Fermi level moves towards the majority band edge. Excess carriers, introduced for example by photogeneration, modify the formation enthalpy of semiconductor defects and thus can be harnessed during crystal growth or annealing to suppress defect populations. Herein we develop a rigorous and general model for defect formation in the presence of steady-statemore » excess carrier concentrations by combining the standard quasi-chemical formalism with a detailed-balance description that is applicable for any defect state in the bandgap. Considering the quasi-Fermi levels as chemical potentials, we demonstrate that increasing the minority carrier concentration increases the formation enthalpy for typical compensating centers, thus suppressing their formation. Furthermore, this effect is illustrated for the specific example of GaSb. While our treatment is generalized for excess carrier injection or generation in semiconductors by any means, we provide a set of guidelines for applying the concept in photoassisted physical vapor deposition.« less

Preconception carrier screening for multiple disorders: evaluation of a screening offer in a Dutch founder population.

PubMed

Mathijssen, Inge B; Holtkamp, Kim C A; Ottenheim, Cecile P E; van Eeten-Nijman, Janneke M C; Lakeman, Phillis; Meijers-Heijboer, Hanne; van Maarle, Merel C; Henneman, Lidewij

2018-02-01

Technological developments have enabled carrier screening for multiple disorders. This study evaluated experiences with a preconception carrier screening offer for four recessive disorders in a Dutch founder population. Questionnaires were completed by 182 attendees pretesting and posttesting and by 137 non-attendees. Semistructured interviews were conducted with seven of the eight carrier couples. Attendees were mainly informed about the existence of screening by friends/colleagues (49%) and family members (44%). Familiarity with the genetic disorders was high. Knowledge after counseling increased (p < 0.001); however, still 9%, compared to 29% before counseling, wrongly mentioned an increased risk of having an affected child if both parents are carriers of different disorders. Most attendees (97%) recalled their test results correctly, but two couples reported being carrier of another disorder than reported. Overall, 63% felt worried while waiting for results but anxiety levels returned to normal afterwards. In all, 2/39 (5%) carriers felt less healthy. Screened individuals were very satisfied; they did not regret testing (97%) and would recommend testing to others (97%). The majority (94%) stated that couples should always have a pretest consultation, preferably by a genetic counselor rather than their general practitioner (83%). All carrier couples made reproductive decisions based on their results. Main reason for non-attendance was unawareness of the screening offer. With expanded carrier screening, adequately informing couples pretest and posttesting is of foremost importance. Close influencers (family/friends) can be used to raise awareness of a screening offer. Our findings provide lessons for the implementation of expanded carrier screening panels in other communities and other settings.

Nanoionic devices: Interface nanoarchitechtonics for physical property tuning and enhancement

NASA Astrophysics Data System (ADS)

Tsuchiya, Takashi; Terabe, Kazuya; Yang, Rui; Aono, Masakazu

2016-11-01

Nanoionic devices have been developed to generate novel functions overcoming limitations of conventional materials synthesis and semiconductor technology. Various physical properties can be tuned and enhanced by local ion transport near the solid/solid interface. Two electronic carrier doping methods can be used to achieve extremely high-density electronic carriers: one is electrostatic carrier doping using an electric double layer (EDL); the other is electrochemical carrier doping using a redox reaction. Atomistic restructuring near the solid/solid interface driven by a DC voltage, namely, interface nanoarchitechtonics, has huge potential. For instance, the use of EDL enables high-density carrier doping in potential superconductors, which can hardly accept chemical doping, in order to achieve room-temperature superconductivity. Optical bandgap and photoluminescence can be controlled for various applications including smart windows and biosensors. In situ tuning of magnetic properties is promising for low-power-consumption spintronics. Synaptic plasticity in the human brain is achieved in neuromorphic devices.

Effect of Carrier Thermalization Dynamics on Light Emission and Amplification in Organometal Halide Perovskites.

PubMed

Chen, Kai; Barker, Alex J; Morgan, Francis L C; Halpert, Jonathan E; Hodgkiss, Justin M

2015-01-02

The remarkable rise of organometal halide perovskites as solar photovoltaic materials has been followed by promising developments in light-emitting devices, including lasers. Here we present unique insights into the processes leading to photon emission in these materials. We employ ultrafast broadband photoluminescence (PL) and transient absorption spectroscopies to directly link density dependent ultrafast charge dynamics to PL. We find that exceptionally strong PL at the band edge is preceded by thermalization of free charge carriers. Short-lived PL above the band gap is clear evidence of nonexcitonic emission from hot carriers, and ultrafast PL depolarization confirms that uncorrelated charge pairs are precursors to photon emission. Carrier thermalization has a profound effect on amplified stimulated emission at high fluence; the delayed onset of optical gain we resolve within the first 10 ps and the unusual oscillatory behavior are both consequences of the kinetic interplay between carrier thermalization and optical gain.

Evaluation of local free carrier concentrations in individual heavily-doped GaN:Si micro-rods by micro-Raman spectroscopy

NASA Astrophysics Data System (ADS)

Mohajerani, M. S.; Khachadorian, S.; Schimpke, T.; Nenstiel, C.; Hartmann, J.; Ledig, J.; Avramescu, A.; Strassburg, M.; Hoffmann, A.; Waag, A.

2016-02-01

Three-dimensional III-nitride micro-structures are being developed as a promising candidate for the future opto-electrical devices. In this study, we demonstrate a quick and straight-forward method to locally evaluate free-carrier concentrations and a crystalline quality in individual GaN:Si micro-rods. By employing micro-Raman mapping and analyzing lower frequency branch of A1(LO)- and E1(LO)-phonon-plasmon-coupled modes (LPP-), the free carrier concentrations are determined in axial and planar configurations, respectively. Due to a gradual doping profile along the micro-rods, a highly spatially resolved mapping on the sidewall is exploited to reconstruct free carrier concentration profile along the GaN:Si micro-rods. Despite remarkably high free carrier concentrations above 1 × 1020 cm-3, the micro-rods reveal an excellent crystalline quality, without a doping-induced stress.

In vivo evaluation of a simvastatin-loaded nanostructured lipid carrier for bone tissue regeneration

NASA Astrophysics Data System (ADS)

Yue, Xinxin; Niu, Mao; Zhang, Te; Wang, Cheng; Wang, Zhonglei; Wu, Wangxi; Zhang, Qi; Lai, Chunhua; Zhou, Lei

2016-03-01

Alveolar bone loss has long been a challenge in clinical dental implant therapy. Simvastatin (SV) has been demonstrated to exert excellent anabolic effects on bone. However, the successful use of SV to increase bone formation in vivo largely depends on the local concentration of SV at the site of action, and there have been continuing efforts to develop an appropriate delivery system. Specifically, nanostructured lipid carrier (NLC) systems have become a popular type of encapsulation carrier system. Therefore, SV-loaded NLCs (SNs) (179.4 nm in diameter) were fabricated in this study, and the osteogenic effect of the SNs was evaluated in a critical-sized rabbit calvarial defect. Our results revealed that the SNs significantly enhanced bone formation in vivo, as evaluated by hematoxylin and eosin (HE) staining, immunohistochemistry, and a fluorescence analysis. Thus, this novel nanostructured carrier system could be a potential encapsulation carrier system for SV in bone regeneration applications.

Simultaneous determination of effective carrier lifetime and resistivity of Si wafers using the nonlinear nature of photocarrier radiometric signals

NASA Astrophysics Data System (ADS)

Sun, Qiming; Melnikov, Alexander; Wang, Jing; Mandelis, Andreas

2018-04-01

A rigorous treatment of the nonlinear behavior of photocarrier radiometric (PCR) signals is presented theoretically and experimentally for the quantitative characterization of semiconductor photocarrier recombination and transport properties. A frequency-domain model based on the carrier rate equation and the classical carrier radiative recombination theory was developed. The derived concise expression reveals different functionalities of the PCR amplitude and phase channels: the phase bears direct quantitative correlation with the carrier effective lifetime, while the amplitude versus the estimated photocarrier density dependence can be used to extract the equilibrium majority carrier density and thus, resistivity. An experimental ‘ripple’ optical excitation mode (small modulation depth compared to the dc level) was introduced to bypass the complicated ‘modulated lifetime’ problem so as to simplify theoretical interpretation and guarantee measurement self-consistency and reliability. Two Si wafers with known resistivity values were tested to validate the method.

Conjugating binary systems for spacecraft thermal control. Appendix C: Aeroassist Flight Experiment Carrier Vehicle preliminary stress analysis

NASA Technical Reports Server (NTRS)

Ingram, J. E.; Murray, T. O.

1989-01-01

An assessment of the static strength of the Aeroassist Flight Experiment (AFE) Carrier Vehicle is presented. The Carrier Vehicle is the structural component which provides the mounting platform for the experiments, on-board computers, batteries, and other black boxes. In addition, the Solid Rocket Motor (SRM), the Thrusters, and the Aerobrake are all attached directly to the Carrier Vehicle. The basic approach in this analysis was to develop a NASTRAN Finite Element Model as a parallel effort to the preliminary design, and to use the internal loads from this model to perform the stress analysis. The NASTRAN method of Inertial Relief was employed. This method involves either specifying a set of CG (center of gravity) accelerations or applying forces at the CG and representing the Carrier Vehicle and all its mounted devices with the proper stiffness and mass properties.

Payload/orbiter contamination control requirement study

NASA Technical Reports Server (NTRS)

Bareiss, L. E.; Ress, E. B.

1975-01-01

The results of a contamination impact analysis upon the spacelab carrier and the spacelab carrier upon some of its potential payloads are presented. These results are based upon contamination computer modeling techniques developed to predict the induced environment for spacelab and to provide the basis for evaluation of the predicted environment against the current on orbit contamination control criteria as specified for payloads. Those spacelab carrier contamination sources evaluated against the stated contamination control criteria were outgassing/offgassing of the major nonmetallic thermal control coating of the spacelab carriers, spacelab core and experiment module and tunnel cabin atmosphere leakage, avionics bay vent, spacelab condensate vent, random particulate sloughing, and the return flux of the molecular content of these sources from the gas-gas interactions with the ambient orbital environment. It is indicated that the spacelab carrier can meet the intent of the contamination control criteria through incorporating known contamination control practices.

Design of porous microparticles with single-micron size by novel spray freeze-drying technique using four-fluid nozzle.

PubMed

Niwa, Toshiyuki; Shimabara, Hiroko; Kondo, Masahiro; Danjo, Kazumi

2009-12-01

Spray freeze-drying (SFD) process, which is a novel particle design technique previously developed by authors, has been improved by using four-fluid nozzle (4N) instead of conventional two-fluid nozzle (2N) to expand its application in pharmaceutical industry. Aqueous spray solutions of the drug and the polymeric carrier were separately supplied into 4N, and atomized while colliding with each other at the tip of nozzle. The droplets of mixed solutions were directly immersed into liquid nitrogen and immediately frozen to form a suspension. Then, the iced droplets were lyophilized by freeze-dryer to prepare the composite particles of the drug and carrier. This process has been used in the present study to modify and enhance the dissolution profiles of poorly water-soluble drug, phenytoin. Water-soluble and enteric polymeric carriers in pharmaceutical use were used as a dissolution modifier. The SFD composite particles prepared by using 4N were fully characterized compared to those using 2N from morphological and physicochemical perspectives. It was found that the particles have fine porous structure producing vast specific surface area. Further, phenytoin was completely dispersed as amorphous state in the polymeric matrix with higher carrier ratio than phenytoin:carrier = 1:3. The dissolution of phenytoin from the water-soluble carrier-based particles was greatly enhanced because of large effective surface area and disappearance of crystalline. On the other hand, the release profiles from enteric carrier-based particles showed the typical enteric patterns, that is, delayed in acidic medium and accelerated in neutral pH. The results demonstrated that SFD technique using 4N has potential to develop the novel solubilized formulation for poorly water-soluble APIs.

High drug-loading nanomedicines: progress, current status, and prospects

PubMed Central

Shen, Shihong; Wu, Youshen; Liu, Yongchun; Wu, Daocheng

2017-01-01

Drug molecules transformed into nanoparticles or endowed with nanostructures with or without the aid of carrier materials are referred to as “nanomedicines” and can overcome some inherent drawbacks of free drugs, such as poor water solubility, high drug dosage, and short drug half-life in vivo. However, most of the existing nanomedicines possess the drawback of low drug-loading (generally less than 10%) associated with more carrier materials. For intravenous administration, the extensive use of carrier materials might cause systemic toxicity and impose an extra burden of degradation, metabolism, and excretion of the materials for patients. Therefore, on the premise of guaranteeing therapeutic effect and function, reducing or avoiding the use of carrier materials is a promising alternative approach to solve these problems. Recently, high drug-loading nanomedicines, which have a drug-loading content higher than 10%, are attracting increasing interest. According to the fabrication strategies of nanomedicines, high drug-loading nanomedicines are divided into four main classes: nanomedicines with inert porous material as carrier, nanomedicines with drug as part of carrier, carrier-free nanomedicines, and nanomedicines following niche and complex strategies. To date, most of the existing high drug-loading nanomedicines belong to the first class, and few research studies have focused on other classes. In this review, we investigate the research status of high drug-loading nanomedicines and discuss the features of their fabrication strategies and optimum proposal in detail. We also point out deficiencies and developing direction of high drug-loading nanomedicines. We envision that high drug-loading nanomedicines will occupy an important position in the field of drug-delivery systems, and hope that novel perspectives will be proposed for the development of high drug-loading nanomedicines. PMID:28615938

Colloidal microgels in drug delivery applications

PubMed Central

Vinogradov, Serguei V.

2005-01-01

Colloidal microgels have recently received attention as environmentally responsive systems and now are increasingly used in applications as carriers for therapeutic drugs and diagnostic agents. Synthetic microgels consist of a crosslinked polymer network that provides a depot for loaded drugs, protection against environmental hazards and template for post-synthetic modification or vectorization of the drug carriers. The aim of this manuscript is to review recent attempts to develop new microgel formulations for oral drug delivery, to design metal-containing microgels for diagnostic and therapeutic applications, and to advance approaches including the systemic administration of microgels. Novel nanogel drug delivery systems developed in the authors’ laboratory are discussed in details including aspects of their synthesis, vectorization and recent applications for encapsulation of low molecular weight drugs or formulation of biological macromolecules. The findings reviewed here are encouraging for further development of the nanogels as intelligent drug carriers with such features as targeted delivery and triggered drug release. PMID:17168773

Virtualization in network and servers infrastructure to support dynamic system reconfiguration in ALMA

NASA Astrophysics Data System (ADS)

Shen, Tzu-Chiang; Ovando, Nicolás.; Bartsch, Marcelo; Simmond, Max; Vélez, Gastón; Robles, Manuel; Soto, Rubén.; Ibsen, Jorge; Saldias, Christian

2012-09-01

ALMA is the first astronomical project being constructed and operated under industrial approach due to the huge amount of elements involved. In order to achieve the maximum through put during the engineering and scientific commissioning phase, several production lines have been established to work in parallel. This decision required modification in the original system architecture in which all the elements are controlled and operated within a unique Standard Test Environment (STE). The advance in the network industry and together with the maturity of virtualization paradigm allows us to provide a solution which can replicate the STE infrastructure without changing their network address definition. This is only possible with Virtual Routing and Forwarding (VRF) and Virtual LAN (VLAN) concepts. The solution allows dynamic reconfiguration of antennas and other hardware across the production lines with minimum time and zero human intervention in the cabling. We also push the virtualization even further, classical rack mount servers are being replaced and consolidated by blade servers. On top of them virtualized server are centrally administrated with VMWare ESX. Hardware costs and system administration effort will be reduced considerably. This mechanism has been established and operated successfully during the last two years. This experience gave us confident to propose a solution to divide the main operation array into subarrays using the same concept which will introduce huge flexibility and efficiency for ALMA operation and eventually may simplify the complexity of ALMA core observing software since there will be no need to deal with subarrays complexity at software level.

Design and development of a multifunctional nano carrier system for imaging, drug delivery, and cell targeting in cancer research

NASA Astrophysics Data System (ADS)

Cho, Hoon-Sung

There has been an increasing need in the last decade for early diagnosis and treatment of cancer prior to the tumor mass becoming evident as anatomical anomaly. A major challenge in cancer diagnosis is to distinguish cancer cells from the surrounding, normal tissue. For early cancer diagnosis and treatment, a nano carrier system was designed and developed with key components uniquely structured according to biomedical and clinical requirements: targeting, drug storage capabilities, fluorescent emissions near the infrared range for in vivo imaging, and magnetic hyperthermia. For in vivo imaging, quantum dots with emissions near infrared range (˜800 nm) were conjugated onto the surface of carbon nanotubes and nanospheres consisting of a spherical polystyrene matrix (˜100 nm) and high fraction of superparamagnetic Fe3O4 nanoparticles (˜10 nm) embedded. The QDs on these nano carriers exhibited intense visible emissions using fluorescent spectroscopy and successfully facilitated in vivo soft tissue imaging in mice. For drug storage, the chemotherapeutic agent, paclitaxel (PTX) was loaded onto the surfaces of these nano-carriers by using a layer of biodegradable poly(lactic-co-glycolic acid) (PLGA). A cell-based cytotoxicity assay was employed to verify successful loading of pharmacologically active drug, PTX. Cell viability of human, metastatic PC3mm2 prostate cancer cells was assessed in the presence and absence of various nano-carrier populations using the MTT assay. For hyperthermia, Fe3O 4 nanoparticles were conjugated onto the surfaces of carbon nanotubes (CNT) and embedded into the nanospheres. Magnetization measurements showed nearly reversible hysteresis curves from the Fe3O4-conjugated CNTs and the magnetic nanospheres (MNS). Application of an alternating electromagnetic field effectively induced heating the solution of the Fe3O 4-conjugated CNTs and the magnetic nanospheres (MNS) into temperature ranges (up to 55ºC) suitable for therapeutic hyperthermia. PTX loaded nanocarrier systems were, then, developed by conjugating anti-Prostate Specific Membrane Antigen (anti-PSMA) for in vitro and in vivo targeting. Specific detection studies of anti-PSMA-conjugated nano carrier systems binding activity in LNCaP prostate cancer cells were carried out. Substantial differences were observed between the targeted- and nontargeted nano carriers. LNCaP cells were targeted successfully by the conjugation of anti-PSMA on the nano carrier surfaces. To explore in vivo targeting, the nano carriers conjugated with anti-PSMA were intravenously injected into nude mice bearing a human prostate cancer cell (LNCaP). Upon post-injection, significant fluorescence attributed to the nano-carrier system was detected, indicating substantial uptake in the region of the tumor.

Comparison of HTLV-I Proviral Load in Adult T Cell Leukemia/Lymphoma (ATL), HTLV-I-Associated Myelopathy (HAM-TSP) and Healthy Carriers.

PubMed

Akbarin, Mohammad Mehdi; Rahimi, Hossein; Hassannia, Tahereh; Shoja Razavi, Ghazaleh; Sabet, Faezeh; Shirdel, Abbas

2013-03-01

Human T Lymphocyte Virus Type one (HTLV-I) is a retrovirus that infects about 10-20 million people worldwide. Khorasan province in Iran is an endemic area. The majority of HTLV-I-infected individuals sustain healthy carriers but small proportion of infected population developed two progressive diseases: HAM/TSP and ATL. The proviral load could be a virological marker for disease monitoring, therefore in the present study HTLV-I proviral load has been evaluated in ATL and compared to HAM/TSP and healthy carriers. In this case series study, 47 HTLV-I infected individuals including 13 ATL, 23 HAM/TSP and 11 asymptomatic subjects were studied. Peripheral blood mononuclear cells (PBMCs) were investigated for presence of HTLV-I DNA provirus by PCR using LTR and Tax fragments. Then in infected subjects, HTLV-I proviral load was measured using real time PCR TaqMan method. The average age of patients in ATL was 52±8, in HAM/TSP 45.52±15.17 and in carrier's 38.65±14.9 years which differences were not statistically significant. The analysis of data showed a significant difference in mean WBC among study groups (ATL vs HAM/TSP and carriers P=0.0001). Moreover, mean HTLV-I proviral load was 11967.2 ± 5078, 409 ± 71.3 and 373.6 ± 143.3 in ATL, HAM/TSP and Healthy Carriers, respectively. The highest HTLV-I proviral load was measured in ATL group that had a significant correlation with WBC count (R=0.495, P=0.001). The proviral load variations between study groups was strongly significant (ATL vs carrier P=0.0001; ATL vs HAM/TSP P= 0.0001 and HAM/TSP vs carriers P< 0.05). Conclusion : The present study demonstrated that HTLV-I proviral load was higher in ATL group in comparison with HAM/TSP and healthy carriers. Therefore, HTLV-I proviral load is a prognostic factor for development of HTLV-I associated diseases and can be used as a monitoring marker for the efficiency of therapeutic regime.

Common breast cancer susceptibility alleles and the risk of breast cancer for BRCA1 and BRCA2 mutation carriers: implications for risk prediction.

PubMed

Antoniou, Antonis C; Beesley, Jonathan; McGuffog, Lesley; Sinilnikova, Olga M; Healey, Sue; Neuhausen, Susan L; Ding, Yuan Chun; Rebbeck, Timothy R; Weitzel, Jeffrey N; Lynch, Henry T; Isaacs, Claudine; Ganz, Patricia A; Tomlinson, Gail; Olopade, Olufunmilayo I; Couch, Fergus J; Wang, Xianshu; Lindor, Noralane M; Pankratz, Vernon S; Radice, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Barile, Monica; Viel, Alessandra; Allavena, Anna; Dall'Olio, Valentina; Peterlongo, Paolo; Szabo, Csilla I; Zikan, Michal; Claes, Kathleen; Poppe, Bruce; Foretova, Lenka; Mai, Phuong L; Greene, Mark H; Rennert, Gad; Lejbkowicz, Flavio; Glendon, Gord; Ozcelik, Hilmi; Andrulis, Irene L; Thomassen, Mads; Gerdes, Anne-Marie; Sunde, Lone; Cruger, Dorthe; Birk Jensen, Uffe; Caligo, Maria; Friedman, Eitan; Kaufman, Bella; Laitman, Yael; Milgrom, Roni; Dubrovsky, Maya; Cohen, Shimrit; Borg, Ake; Jernström, Helena; Lindblom, Annika; Rantala, Johanna; Stenmark-Askmalm, Marie; Melin, Beatrice; Nathanson, Kate; Domchek, Susan; Jakubowska, Ania; Lubinski, Jan; Huzarski, Tomasz; Osorio, Ana; Lasa, Adriana; Durán, Mercedes; Tejada, Maria-Isabel; Godino, Javier; Benitez, Javier; Hamann, Ute; Kriege, Mieke; Hoogerbrugge, Nicoline; van der Luijt, Rob B; van Asperen, Christi J; Devilee, Peter; Meijers-Heijboer, E J; Blok, Marinus J; Aalfs, Cora M; Hogervorst, Frans; Rookus, Matti; Cook, Margaret; Oliver, Clare; Frost, Debra; Conroy, Don; Evans, D Gareth; Lalloo, Fiona; Pichert, Gabriella; Davidson, Rosemarie; Cole, Trevor; Cook, Jackie; Paterson, Joan; Hodgson, Shirley; Morrison, Patrick J; Porteous, Mary E; Walker, Lisa; Kennedy, M John; Dorkins, Huw; Peock, Susan; Godwin, Andrew K; Stoppa-Lyonnet, Dominique; de Pauw, Antoine; Mazoyer, Sylvie; Bonadona, Valérie; Lasset, Christine; Dreyfus, Hélène; Leroux, Dominique; Hardouin, Agnès; Berthet, Pascaline; Faivre, Laurence; Loustalot, Catherine; Noguchi, Tetsuro; Sobol, Hagay; Rouleau, Etienne; Nogues, Catherine; Frénay, Marc; Vénat-Bouvet, Laurence; Hopper, John L; Daly, Mary B; Terry, Mary B; John, Esther M; Buys, Saundra S; Yassin, Yosuf; Miron, Alexander; Goldgar, David; Singer, Christian F; Dressler, Anne Catharina; Gschwantler-Kaulich, Daphne; Pfeiler, Georg; Hansen, Thomas V O; Jønson, Lars; Agnarsson, Bjarni A; Kirchhoff, Tomas; Offit, Kenneth; Devlin, Vincent; Dutra-Clarke, Ana; Piedmonte, Marion; Rodriguez, Gustavo C; Wakeley, Katie; Boggess, John F; Basil, Jack; Schwartz, Peter E; Blank, Stephanie V; Toland, Amanda Ewart; Montagna, Marco; Casella, Cinzia; Imyanitov, Evgeny; Tihomirova, Laima; Blanco, Ignacio; Lazaro, Conxi; Ramus, Susan J; Sucheston, Lara; Karlan, Beth Y; Gross, Jenny; Schmutzler, Rita; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Lochmann, Magdalena; Arnold, Norbert; Heidemann, Simone; Varon-Mateeva, Raymonda; Niederacher, Dieter; Sutter, Christian; Deissler, Helmut; Gadzicki, Dorothea; Preisler-Adams, Sabine; Kast, Karin; Schönbuchner, Ines; Caldes, Trinidad; de la Hoya, Miguel; Aittomäki, Kristiina; Nevanlinna, Heli; Simard, Jacques; Spurdle, Amanda B; Holland, Helene; Chen, Xiaoqing; Platte, Radka; Chenevix-Trench, Georgia; Easton, Douglas F

2010-12-01

The known breast cancer susceptibility polymorphisms in FGFR2, TNRC9/TOX3, MAP3K1, LSP1, and 2q35 confer increased risks of breast cancer for BRCA1 or BRCA2 mutation carriers. We evaluated the associations of 3 additional single nucleotide polymorphisms (SNPs), rs4973768 in SLC4A7/NEK10, rs6504950 in STXBP4/COX11, and rs10941679 at 5p12, and reanalyzed the previous associations using additional carriers in a sample of 12,525 BRCA1 and 7,409 BRCA2 carriers. Additionally, we investigated potential interactions between SNPs and assessed the implications for risk prediction. The minor alleles of rs4973768 and rs10941679 were associated with increased breast cancer risk for BRCA2 carriers (per-allele HR = 1.10, 95% CI: 1.03-1.18, P = 0.006 and HR = 1.09, 95% CI: 1.01-1.19, P = 0.03, respectively). Neither SNP was associated with breast cancer risk for BRCA1 carriers, and rs6504950 was not associated with breast cancer for either BRCA1 or BRCA2 carriers. Of the 9 polymorphisms investigated, 7 were associated with breast cancer for BRCA2 carriers (FGFR2, TOX3, MAP3K1, LSP1, 2q35, SLC4A7, 5p12, P = 7 × 10(-11) - 0.03), but only TOX3 and 2q35 were associated with the risk for BRCA1 carriers (P = 0.0049, 0.03, respectively). All risk-associated polymorphisms appear to interact multiplicatively on breast cancer risk for mutation carriers. Based on the joint genotype distribution of the 7 risk-associated SNPs in BRCA2 mutation carriers, the 5% of BRCA2 carriers at highest risk (i.e., between 95th and 100th percentiles) were predicted to have a probability between 80% and 96% of developing breast cancer by age 80, compared with 42% to 50% for the 5% of carriers at lowest risk. Our findings indicated that these risk differences might be sufficient to influence the clinical management of mutation carriers.

Common breast cancer susceptibility alleles and the risk of breast cancer for BRCA1 and BRCA2 mutation carriers: implications for risk prediction

PubMed Central

Antoniou, Antonis C; Beesley, Jonathan; McGuffog, Lesley; Sinilnikova, Olga M.; Healey, Sue; Neuhausen, Susan L.; Ding, Yuan Chun; Rebbeck, Timothy R.; Weitzel, Jeffrey N.; Lynch, Henry T.; Isaacs, Claudine; Ganz, Patricia A.; Tomlinson, Gail; Olopade, Olufunmilayo I.; Couch, Fergus J.; Wang, Xianshu; Lindor, Noralane M.; Pankratz, Vernon S.; Radice, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Barile, Monica; Viel, Alessandra; Allavena, Anna; Dall’Olio, Valentina; Peterlongo, Paolo; Szabo, Csilla I.; Zikan, Michal; Claes, Kathleen; Poppe, Bruce; Foretova, Lenka; Mai, Phuong L.; Greene, Mark H.; Rennert, Gad; Lejbkowicz, Flavio; Glendon, Gord; Ozcelik, Hilmi; Andrulis, Irene L.; Thomassen, Mads; Gerdes, Anne-Marie; Sunde, Lone; Cruger, Dorthe; Jensen, Uffe Birk; Caligo, Maria; Friedman, Eitan; Kaufman, Bella; Laitman, Yael; Milgrom, Roni; Dubrovsky, Maya; Cohen, Shimrit; Borg, Ake; Jernström, Helena; Lindblom, Annika; Rantala, Johanna; Stenmark-Askmalm, Marie; Melin, Beatrice; Nathanson, Kate; Domchek, Susan; Jakubowska, Ania; Lubinski, Jan; Huzarski, Tomasz; Osorio, Ana; Lasa, Adriana; Durán, Mercedes; Tejada, Maria-Isabel; Godino, Javier; Benitez, Javier; Hamann, Ute; Kriege, Mieke; Hoogerbrugge, Nicoline; van der Luijt, Rob B; van Asperen, Christi J; Devilee, Peter; Meijers-Heijboer, E.J.; Blok, Marinus J; Aalfs, Cora M.; Hogervorst, Frans; Rookus, Matti; Cook, Margaret; Oliver, Clare; Frost, Debra; Conroy, Don; Evans, D. Gareth; Lalloo, Fiona; Pichert, Gabriella; Davidson, Rosemarie; Cole, Trevor; Cook, Jackie; Paterson, Joan; Hodgson, Shirley; Morrison, Patrick J.; Porteous, Mary E.; Walker, Lisa; Kennedy, M. John; Dorkins, Huw; Peock, Susan; Godwin, Andrew K.; Stoppa-Lyonnet, Dominique; de Pauw, Antoine; Mazoyer, Sylvie; Bonadona, Valérie; Lasset, Christine; Dreyfus, Hélène; Leroux, Dominique; Hardouin, Agnès; Berthet, Pascaline; Faivre, Laurence; Loustalot, Catherine; Noguchi, Tetsuro; Sobol, Hagay; Rouleau, Etienne; Nogues, Catherine; Frénay, Marc; Vénat-Bouvet, Laurence; Hopper, John L.; Daly, Mary B.; Terry, Mary B.; John, Esther M.; Buys, Saundra S.; Yassin, Yosuf; Miron, Alex; Goldgar, David; Singer, Christian F.; Dressler, Anne Catharina; Gschwantler-Kaulich, Daphne; Pfeiler, Georg; Hansen, Thomas V. O.; Jønson, Lars; Agnarsson, Bjarni A.; Kirchhoff, Tomas; Offit, Kenneth; Devlin, Vincent; Dutra-Clarke, Ana; Piedmonte, Marion; Rodriguez, Gustavo C.; Wakeley, Katie; Boggess, John F.; Basil, Jack; Schwartz, Peter E.; Blank, Stephanie V.; Toland, Amanda Ewart; Montagna, Marco; Casella, Cinzia; Imyanitov, Evgeny; Tihomirova, Laima; Blanco, Ignacio; Lazaro, Conxi; Ramus, Susan J.; Sucheston, Lara; Karlan, Beth Y.; Gross, Jenny; Schmutzler, Rita; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Lochmann, Magdalena; Arnold, Norbert; Heidemann, Simone; Varon-Mateeva, Raymonda; Niederacher, Dieter; Sutter, Christian; Deissler, Helmut; Gadzicki, Dorothea; Preisler-Adams, Sabine; Kast, Karin; Schönbuchner, Ines; Caldes, Trinidad; de la Hoya, Miguel; Aittomäki, Kristiina; Nevanlinna, Heli; Simard, Jacques; Spurdle, Amanda B.; Holland, Helene; Chen, Xiaoqing; Platte, Radka; Chenevix-Trench, Georgia; Easton, Douglas F.

2010-01-01

The known breast cancer (BC) susceptibility polymorphisms in FGFR2, TNRC9/TOX3, MAP3K1,LSP1 and 2q35 confer increased risks of BC for BRCA1 or BRCA2 mutation carriers. We evaluated the associations of three additional SNPs, rs4973768 in SLC4A7/NEK10, rs6504950 in STXBP4/COX11 and rs10941679 at 5p12 and reanalyzed the previous associations using additional carriers in a sample of 12,525 BRCA1 and 7,409 BRCA2 carriers. Additionally, we investigated potential interactions between SNPs and assessed the implications for risk prediction. The minor alleles of rs4973768 and rs10941679 were associated with increased BC risk for BRCA2 carriers (per-allele Hazard Ratio (HR)=1.10, 95%CI:1.03-1.18, p=0.006 and HR=1.09, 95%CI:1.01-1.19, p=0.03, respectively). Neither SNP was associated with BC risk for BRCA1 carriers and rs6504950 was not associated with BC for either BRCA1 or BRCA2 carriers. Of the nine polymorphisms investigated, seven were associated with BC for BRCA2 carriers (FGFR2, TOX3, MAP3K1, LSP1, 2q35, SLC4A7, 5p12, p-values:7×10−11-0.03), but only TOX3 and 2q35 were associated with the risk for BRCA1 carriers (p=0.0049, 0.03 respectively). All risk associated polymorphisms appear to interact multiplicatively on BC risk for mutation carriers. Based on the joint genotype distribution of the seven risk associated SNPs in BRCA2 mutation carriers, the 5% of BRCA2 carriers at highest risk (i.e. between 95th and 100th percentiles) were predicted to have a probability between 80% and 96% of developing BC by age 80, compared with 42-50% for the 5% of carriers at lowest risk. Our findings indicated that these risk differences may be sufficient to influence the clinical management of mutation carriers. PMID:21118973

A firm size and safety performance profile of the U.S. motor carrier industry.

DOT National Transportation Integrated Search

2014-12-01

The purpose of this study was the development of a driver-focused truck crash prediction model with a particular focus on the size of : the carrier that the driver is associated with at the time of a state reportable crash. While previous studies hav...

An Autosampler and Field Sample Carrier for Maximizing Throughput Using an Open-Air, Surface Sampling Ion Source for MS

EPA Science Inventory

A recently developed, commercially available, open-air, surface sampling ion source for mass spectrometers provides individual analyses in several seconds. To realize its full throughput potential, an autosampler and field sample carrier were designed and built. The autosampler ...

75 FR 18255 - Passenger Facility Charge Database System for Air Carrier Reporting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... Facility Charge Database System for Air Carrier Reporting AGENCY: Federal Aviation Administration (FAA... the Passenger Facility Charge (PFC) database system to report PFC quarterly report information. In... developed a national PFC database system in order to more easily track the PFC program on a nationwide basis...

Troop Carriers at Normandy and Corregidor: Enduring Lessons for Tactical Airlift

DTIC Science & Technology

During World War II, troop carrier aviation developed as a new form of combat flying in order to support emerging airborne tactics. Throughout the...of World War II. The second is that modern airlift doctrine and joint practices can improve in how they address air integration and cooperation

Development of Low Temperature Inverted Angle for LPG Carrier Using Slab

NASA Astrophysics Data System (ADS)

Doo, Wonchul; Lee, Chulwon; Cho, Sungkyu

Hyundai Steel Company had developed the inverted angles as second only to the Japan steel maker in 1992. Current market share of Hyundai Steel Company is second position after JFE Steel Corporation. Main application of the inverted angles is the reinforcement of shipbuilding as the stiffener of hull. Hyundai Steel Company has also been developing the low temperature steel grade applied for LPG carrier's cargo tank and secondary barrier using slab. This steel grade require the guarantee of -60°C impact toughness and weldability.

Cerebral metabolic abnormalities in A3243G mitochondrial DNA mutation carriers

PubMed Central

Weiduschat, Nora; Kaufmann, Petra; Mao, Xiangling; Engelstad, Kristin Marie; Hinton, Veronica; DiMauro, Salvatore; De Vivo, Darryl

2014-01-01

Objective: To establish cerebral metabolic features associated with the A3243G mitochondrial DNA mutation with proton magnetic resonance spectroscopic imaging (1H MRSI) and to assess their potential as prognostic biomarkers. Methods: In this prospective cohort study, we investigated 135 clinically heterogeneous A3243G mutation carriers and 30 healthy volunteers (HVs) with 1H MRSI. Mutation carriers included 45 patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS); 11 participants who would develop the MELAS syndrome during follow-up (converters); and 79 participants who would not develop the MELAS syndrome during follow-up (nonconverters). The groups were compared with respect to MRSI metabolic indices of 1) anaerobic energy metabolism (lactate), 2) neuronal integrity (N-acetyl-l-aspartate [NAA]), 3) mitochondrial function (NAA; lactate), 4) cell energetics (total creatine), and 5) membrane biosynthesis and turnover (total choline [tCho]). Results: Consistent with prior studies, the patients with MELAS had higher lactate (p < 0.001) and lower NAA levels (p = 0.01) than HVs. Unexpectedly, converters showed higher NAA (p = 0.042), tCho (p = 0.004), and total creatine (p = 0.002), in addition to higher lactate levels (p = 0.032), compared with HVs. Compared with nonconverters, converters had higher tCho (p = 0.015). Clinically, converters and nonconverters did not differ at baseline. Lactate and tCho levels were reliable biomarkers for predicting the risk of individual mutation carriers to develop the MELAS phenotype. Conclusions: 1H MRSI assessment of cerebral metabolism in A3243G mutation carriers shows promise in identifying disease biomarkers as well as individuals at risk of developing the MELAS phenotype. PMID:24477106

Brain Differences in Infants at Differential Genetic Risk for Late-Onset Alzheimer Disease A Cross-sectional Imaging Study

PubMed Central

Dean, Douglas C.; Jerskey, Beth A.; Chen, Kewei; Protas, Hillary; Thiyyagura, Pradeep; Roontiva, Auttawat; O’Muircheartaigh, Jonathan; Dirks, Holly; Waskiewicz, Nicole; Lehman, Katie; Siniard, Ashley L.; Turk, Mari N.; Hua, Xue; Madsen, Sarah K.; Thompson, Paul M.; Fleisher, Adam S.; Huentelman, Matthew J.; Deoni, Sean C. L.; Reiman, Eric M.

2014-01-01

IMPORTANCE Converging evidence suggests brain structure alterations may precede overt cognitive impairment in Alzheimer disease by several decades. Early detection of these alterations holds inherent value for the development and evaluation of preventive treatment therapies. OBJECTIVE To compare magnetic resonance imaging measurements of white matter myelin water fraction (MWF) and gray matter volume (GMV) in healthy infant carriers and noncarriers of the apolipoprotein E (APOE) ε4 allele, the major susceptibility gene for late-onset AD. DESIGN, SETTING, AND PARTICIPANTS Quiet magnetic resonance imaging was performed at an academic research imaging center on 162 healthy, typically developing 2- to 25-month-old infants with no family history of Alzheimer disease or other neurological or psychiatric disorders. Cross-sectional measurements were compared in the APOE ε4 carrier and noncarrier groups. White matter MWF was compared in one hundred sixty-two 2- to 25-month-old sleeping infants (60 ε4 carriers and 102 noncarriers). Gray matter volume was compared in a subset of fifty-nine 6- to 25-month-old infants (23 ε4 carriers and 36 noncarriers), who remained asleep during the scanning session. The carrier and noncarrier groups were matched for age, gestational duration, birth weight, sex ratio, maternal age, education, and socioeconomic status. MAIN OUTCOMES AND MEASURES Automated algorithms compared regional white matter MWF and GMV in the carrier and noncarrier groups and characterized their associations with age. RESULTS Infant ε4 carriers had lower MWF and GMV measurements than noncarriers in precuneus, posterior/middle cingulate, lateral temporal, and medial occipitotemporal regions, areas preferentially affected by AD, and greater MWF and GMV measurements in extensive frontal regions and measurements were also significant in the subset of 2- to 6-month-old infants (MWF differences, P < .05, after correction for multiple comparisons; GMV differences, P < .001, uncorrected for multiple comparisons). Infant ε4 carriers also exhibited an attenuated relationship between MWF and age in posterior white matter regions. CONCLUSIONS AND RELEVANCE While our findings should be considered preliminary, this study demonstrates some of the earliest brain changes associated with the genetic predisposition to AD. It raises new questions about the role of APOE in normal human brain development, the extent to which these processes are related to subsequent AD pathology, and whether they could be targeted by AD prevention therapies. PMID:24276092

Brain differences in infants at differential genetic risk for late-onset Alzheimer disease: a cross-sectional imaging study.

PubMed

Dean, Douglas C; Jerskey, Beth A; Chen, Kewei; Protas, Hillary; Thiyyagura, Pradeep; Roontiva, Auttawat; O'Muircheartaigh, Jonathan; Dirks, Holly; Waskiewicz, Nicole; Lehman, Katie; Siniard, Ashley L; Turk, Mari N; Hua, Xue; Madsen, Sarah K; Thompson, Paul M; Fleisher, Adam S; Huentelman, Matthew J; Deoni, Sean C L; Reiman, Eric M

2014-01-01

Converging evidence suggests brain structure alterations may precede overt cognitive impairment in Alzheimer disease by several decades. Early detection of these alterations holds inherent value for the development and evaluation of preventive treatment therapies. To compare magnetic resonance imaging measurements of white matter myelin water fraction (MWF) and gray matter volume (GMV) in healthy infant carriers and noncarriers of the apolipoprotein E (APOE) ε4 allele, the major susceptibility gene for late-onset AD. Quiet magnetic resonance imaging was performed at an academic research imaging center on 162 healthy, typically developing 2- to 25-month-old infants with no family history of Alzheimer disease or other neurological or psychiatric disorders. Cross-sectional measurements were compared in the APOE ε4 carrier and noncarrier groups. White matter MWF was compared in one hundred sixty-two 2- to 25-month-old sleeping infants (60 ε4 carriers and 102 noncarriers). Gray matter volume was compared in a subset of fifty-nine 6- to 25-month-old infants (23 ε4 carriers and 36 noncarriers), who remained asleep during the scanning session. The carrier and noncarrier groups were matched for age, gestational duration, birth weight, sex ratio, maternal age, education, and socioeconomic status. Automated algorithms compared regional white matter MWF and GMV in the carrier and noncarrier groups and characterized their associations with age. Infant ε4 carriers had lower MWF and GMV measurements than noncarriers in precuneus, posterior/middle cingulate, lateral temporal, and medial occipitotemporal regions, areas preferentially affected by AD, and greater MWF and GMV measurements in extensive frontal regions and measurements were also significant in the subset of 2- to 6-month-old infants (MWF differences, P < .05, after correction for multiple comparisons; GMV differences, P < .001, uncorrected for multiple comparisons). Infant ε4 carriers also exhibited an attenuated relationship between MWF and age in posterior white matter regions. While our findings should be considered preliminary, this study demonstrates some of the earliest brain changes associated with the genetic predisposition to AD. It raises new questions about the role of APOE in normal human brain development, the extent to which these processes are related to subsequent AD pathology, and whether they could be targeted by AD prevention therapies.

78 FR 67799 - Qualification, Service, and Use of Crewmembers and Aircraft Dispatchers

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-12

...This final rule revises the training requirements for pilots in air carrier operations. The regulations enhance air carrier pilot training programs by emphasizing the development of pilots' manual handling skills and adding safety-critical tasks such as recovery from stall and upset. The final rule also requires enhanced runway safety training and pilot monitoring training to be incorporated into existing requirements for scenario-based flight training and requires air carriers to implement remedial training programs for pilots. The FAA expects these changes to contribute to a reduction in aviation accidents. Additionally, the final rule revises recordkeeping requirements for communications between the flightcrew and dispatch; ensures that personnel identified as flight attendants have completed flight attendant training and qualification requirements; provides civil enforcement authority for making fraudulent statements; and, provides a number of conforming and technical changes to existing air carrier crewmember training and qualification requirements. The final rule also includes provisions that provide opportunities for air carriers to modify training program requirements for flightcrew members when the air carrier operates multiple aircraft types with similar design and flight handling characteristics.

The 'Brick Wall' radio loss approximation and the performance of strong channel codes for deep space applications at high data rates

NASA Technical Reports Server (NTRS)

Shambayati, Shervin

2001-01-01

In order to evaluate performance of strong channel codes in presence of imperfect carrier phase tracking for residual carrier BPSK modulation in this paper an approximate 'brick wall' model is developed which is independent of the channel code type for high data rates. It is shown that this approximation is reasonably accurate (less than 0.7dB for low FERs for (1784,1/6) code and less than 0.35dB for low FERs for (5920,1/6) code). Based on the approximation's accuracy, it is concluded that the effects of imperfect carrier tracking are more or less independent of the channel code type for strong channel codes. Therefore, the advantage that one strong channel code has over another with perfect carrier tracking translates to nearly the same advantage under imperfect carrier tracking conditions. This will allow the link designers to incorporate projected channel code performance of strong channel codes into their design tables without worrying about their behavior in the face of imperfect carrier phase tracking.

Efficacy of proximal colectomy for surgical management of right-sided first colorectal cancer in Lynch Syndrome mutation carriers.

PubMed

Hiatt, Molly J; Casey, Murray Joseph; Lynch, Henry T; Snyder, Carrie L; Stacey, Mark; Walters, Ryan W

2018-07-01

This study analyzes the occurrence of colorectal cancer (CRC) in Lynch syndrome (LS) mutation carriers, interval until diagnosis of metachronous CRC, and survival after proximal colectomy (PC) compared with total (TC) and subtotal colectomy (STC) for right-sided first CRC in LS mutation carriers. Sixty-four LS mutation carriers with right-sided first CRC treated with PC or TC + STC were confirmed by clinical records. Bivariate analyses were examined for significance and life tables were generated for risk of metachronous CRC and survival estimates following surgery. One of 16 (6.3%) mutation carriers treated with TC + STC developed subsequent CRC compared with 13/48 (27%) treated by PC. There was no significant difference in survival estimates between PC compared with TC + STC through 25 years after surgery. Risk of subsequent CRC and survival estimates following PC and TC + STC should be considered in surgical management of right-sided first CRC in LS mutation carriers. Copyright © 2017 Elsevier Inc. All rights reserved.

Folic-Acid-Targeted Self-Assembling Supramolecular Carrier for Gene Delivery.

PubMed

Liao, Rongqiang; Yi, Shouhui; Liu, Manshuo; Jin, Wenling; Yang, Bo

2015-07-27

A targeting gene carrier for cancer-specific delivery was successfully developed through a "multilayer bricks-mortar" strategy. The gene carrier was composed of adamantane-functionalized folic acid (FA-AD), an adamantane-functionalized poly(ethylene glycol) derivative (PEG-AD), and β-cyclodextrin-grafted low-molecular-weight branched polyethylenimine (PEI-CD). Carriers produced by two different self-assembly schemes, involving either precomplexation of the PEI-CD with the FA-AD and PEG-AD before pDNA condensation (Method A) or pDNA condensation with the PEI-CD prior to addition of the FA-AD and PEG-AD to engage host-guest complexation (Method B) were investigated for their ability to compact pDNA into nanoparticles. Cell viability studies show that the material produced by the Method A assembly scheme has lower cytotoxicity than branched PEI 25 kDa (PEI-25KD) and that the transfection efficiency is maintained. These findings suggest that the gene carrier, based on multivalent host-guest interactions, could be an effective, targeted, and low-toxicity carrier for delivering nucleic acid to target cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sustained delivery of biomolecules from gelatin carriers for applications in bone regeneration.

PubMed

Song, Jiankang; Leeuwenburgh, Sander Cg

2014-08-01

Local delivery of therapeutic biomolecules to stimulate bone regeneration has matured considerably during the past decades, but control over the release of these biomolecules still remains a major challenge. To this end, suitable carriers that allow for tunable spatial and temporal delivery of biomolecules need to be developed. Gelatin is one of the most widely used natural polymers for the controlled and sustained delivery of biomolecules because of its biodegradability, biocompatibility, biosafety and cost-effectiveness. The current study reviews the applications of gelatin as carriers in form of bulk hydrogels, microspheres, nanospheres, colloidal gels and composites for the programmed delivery of commonly used biomolecules for applications in bone regeneration with a specific focus on the relationship between carrier properties and delivery characteristics.

Picosecond Dynamics Of The GaAs (110) Surface Studied With Laser Photoemission

NASA Astrophysics Data System (ADS)

Haight, R.; Silberman, J. A.; Lilie, M. I.

1988-08-01

A novel laser system and detection scheme is described which has been developed to investigate the transient dynamics of photoexcited electrons at material surfaces and interfaces with photoemission. The excited carrier population on the surface of GaAs (110) and the related Cr/GaAs (110) surface has been studied with 1-2 picosecond time resolution. Studies reveal a rapid rise and fall of the photexcited carrier population at the clean semiconductor surface within 15 picoseconds of excitation. For times greater than 15 picoseconds the carrier density decays slowly. Studies of the photoexcited surface after deposition of small numbers of Cr atoms reveal a remarkable decrease in the carrier density observed at the surface for a coverage as low as .006 monolayer.

eSensor®: A Microarray Technology Based on Electrochemical Detection of Nucleic Acids and Its Application to Cystic Fibrosis Carrier Screening

NASA Astrophysics Data System (ADS)

Reed, Michael R.; Coty, William A.

We have developed a test for identification of carriers for cystic fibrosis using the eSensor® DNA detection technology. Oligonucleotide probes are deposited within self-assembled monolayers on gold electrodes arrayed upon printed circuit boards. These probes allow sequence-specific capture of amplicons containing a panel of mutation sites associated with cystic fibrosis. DNA targets are detected and mutations genotyped using a “sandwich” assay methodology employing electrochemical detection of ferrocene-labeled oligonucleotides for discrimination of carrier and non-carrier alleles. Performance of the cystic fibrosis application demonstrates sufficient accuracy and reliability for clinical diagnostic use, and the procedure can be performed by trained medical technologists available in the hospital laboratory.

Passivation of Si solar cells by hetero-epitaxial compound semiconductor coatings

NASA Technical Reports Server (NTRS)

Vernon, S. M.; Spitzer, M. B.; Keavney, C. J.; Haven, V. E.; Sekula, P. A.

1986-01-01

A development status evaluation is made for high efficiency Si solar cells, with emphasis on the suppression of the deleterious effects of surface recombination. ZnS(0.9)Se(0.1) and GaP are identified as candidates for the reduction of surface recombination. Attention is given to methods developed for the deposition of heteroepitaxial compounds designed to block minority carrier transport to the Si solar cell surface without interfering with the majority carrier flow.

Geographic Region, Weather, Pilot Age and Air Carrier Crashes: a Case-Control Study

PubMed Central

Li, Guohua; Pressley, Joyce C.; Qiang, Yandong; Grabowski, Jurek G.; Baker, Susan P.; Rebok, George W.

2009-01-01

Background Information about risk factors of aviation crashes is crucial for developing effective intervention programs. Previous studies assessing factors associated with crash risk were conducted primarily in general aviation, air taxis and commuter air carriers. Methods A matched case-control design was used to examine the associations of geographic region, basic weather condition, and pilot age with the risk of air carrier (14 CFR Part 121) crash involvement. Cases (n=373) were air carrier crashes involving aircraft made by Boeing, McDonnell Douglas, and Airbus, recorded in the National Transportation Safety Board’s aviation crash database during 1983 through 2002, and controls (n=746) were air carrier incidents involving aircraft of the same three makes selected at random from the Federal Aviation Administration’s aviation incident database. Each case was matched with two controls on the calendar year when the index crash occurred. Conditional logistic regression was used for statistical analysis. Results With adjustment for basic weather condition, pilot age, and total flight time, the risk of air carrier crashes in Alaska was more than three times the risk for other regions [adjusted odds ratio (OR) 3.18, 95% confidence interval (CI) 1.35 – 7.49]. Instrument meteorological conditions were associated with an increased risk for air carrier crashes involving pilot error (adjusted OR 2.26, 95% CI 1.15 – 4.44) and a decreased risk for air carrier crashes without pilot error (adjusted OR 0.57, 95% CI 0.40 – 0.87). Neither pilot age nor total flight time was significantly associated with the risk of air carrier crashes. Conclusions The excess risk of air carrier crashes in Alaska and the effect of adverse weather on pilot-error crashes underscore the importance of environmental hazards in flight safety. PMID:19378910

Geographic region, weather, pilot age, and air carrier crashes: a case-control study.

PubMed

Li, Guohua; Pressley, Joyce C; Qiang, Yandong; Grabowski, Jurek G; Baker, Susan P; Rebok, George W

2009-04-01

Information about risk factors of aviation crashes is crucial for developing effective intervention programs. Previous studies assessing factors associated with crash risk were conducted primarily in general aviation, air taxis, and commuter air carriers. A matched case-control design was used to examine the associations of geographic region, basic weather condition, and pilot age with the risk of air carrier (14 CFR Part 121) crash involvement. Cases (N = 373) were air carrier crashes involving aircraft made by Boeing, McDonnell Douglas, and Airbus recorded in the National Transportation Safety Board's aviation crash database during 1983 through 2002, and controls (N = 746) were air carrier incidents involving aircraft of the same three makes selected at random from the Federal Aviation Administration's aviation incident database. Each case was matched with two controls on the calendar year when the index crash occurred. Conditional logistic regression was used for statistical analysis. With adjustment for basic weather condition, pilot age, and total flight time, the risk of air carrier crashes in Alaska was more than three times the risk for other regions ladjusted odds ratio (OR) 3.18, 95% confidence interval (CI) 1.35-7.49]. Instrument meteorological conditions were associated with an increased risk for air carrier crashes involving pilot error (adjusted OR 2.26, 95% CI 1.15-4.44) and a decreased risk for air carrier crashes without pilot error (adjusted OR 0.60, 95% CI 0.37-0.96). Neither pilot age nor total flight time were significantly associated with the risk of air carrier crashes. The excess risk of air carrier crashes in Alaska and the effect of adverse weather on pilot-error crashes underscore the importance of environmental hazards in flight safety.

Carrier rockets

NASA Astrophysics Data System (ADS)

Aleksandrov, V. A.; Vladimirov, V. V.; Dmitriev, R. D.; Osipov, S. O.

This book takes into consideration domestic and foreign developments related to launch vehicles. General information concerning launch vehicle systems is presented, taking into account details of rocket structure, basic design considerations, and a number of specific Soviet and American launch vehicles. The basic theory of reaction propulsion is discussed, giving attention to physical foundations, the various types of forces acting on a rocket in flight, basic parameters characterizing rocket motion, the effectiveness of various approaches to obtain the desired velocity, and rocket propellants. Basic questions concerning the classification of launch vehicles are considered along with construction and design considerations, aspects of vehicle control, reliability, construction technology, and details of structural design. Attention is also given to details of rocket motor design, the basic systems of the carrier rocket, and questions of carrier rocket development.

Immune-tolerant elastin-like polypeptides (iTEPs) and their application as CTL vaccine carriers.

PubMed

Cho, S; Dong, S; Parent, K N; Chen, M

2016-01-01

Cytotoxic T lymphocyte (CTL) vaccine carriers are known to enhance the efficacy of vaccines, but a search for more effective carriers is warranted. Elastin-like polypeptides (ELPs) have been examined for many medical applications but not as CTL vaccine carriers. We aimed to create immune tolerant ELPs using a new polypeptide engineering practice and create CTL vaccine carriers using the ELPs. Four sets of novel ELPs, termed immune-tolerant elastin-like polypeptide (iTEP) were generated according to the principles dictating humoral immunogenicity of polypeptides and phase transition property of ELPs. The iTEPs were non-immunogenic in mice. Their phase transition feature was confirmed through a turbidity assay. An iTEP nanoparticle (NP) was assembled from an amphiphilic iTEP copolymer plus a CTL peptide vaccine, SIINFEKL. The NP facilitated the presentation of the vaccine by dendritic cells (DCs) and enhanced vaccine-induced CTL responses. A new ELP design and development practice was established. The non-canonical motif and the immune tolerant nature of the iTEPs broaden our insights about ELPs. ELPs, for the first time, were successfully used as carriers for CTL vaccines. It is feasible to concurrently engineer both immune-tolerant and functional peptide materials. ELPs are a promising type of CTL vaccine carriers.

Investigation of efficiency enhancement in InGaN MQW LED with compositionally step graded GaN/InAlN/GaN multi-layer barrier

NASA Astrophysics Data System (ADS)

Prajoon, P.; Anuja Menokey, M.; Charles Pravin, J.; Ajayan, J.; Rajesh, S.; Nirmal, D.

2018-04-01

The advantage of InGaN multiple Quantum well (MQW) Light emitting diode (LED) on a SiC substrate with compositionally step graded GaN/InAlN/GaN multi-layer barrier (MLB) is studied. The Internal quantum efficiency, Optical power, current-voltage characteristics, spontaneous emission rate and carrier distribution profile in the active region are investigated using Sentaurus TCAD simulation. An analytical model is also developed to describe the QW carrier injection efficiency, by including carrier leakage mechanisms like carrier overflow, thermionic emission and tunnelling. The enhanced electron confinement, reduced carrier asymmetry, and suppressed carrier overflow in the active region of the MLB MQW LED leads to render a superior performance than the conventional GaN barrier MQW LED. The simulation result also elucidates the efficiency droop behaviour in the MLB MQW LED, it suggests that the efficiency droop effect is remarkably improved when the GaN barrier is replaced with GaN/InAlN/GaN MLB barrier. The analysis shows a dominating behaviour of carrier escape mechanism due to tunnelling. Moreover, the lower lattice mismatching of SiC substrate with GaN epitaxial layer is attributed with good crystal quality and reduced polarization effect, ultimately enhances the optical performance of the LEDs.

Healthy versus Entorhinal Cortical Atrophy Identification in Asymptomatic APOE4 Carriers at Risk for Alzheimer’s Disease

PubMed Central

Konishi, Kyoko; Joober, Ridha; Poirier, Judes; MacDonald, Kathleen; Chakravarty, Mallar; Patel, Raihaan; Breitner, John; Bohbot, Véronique D.

2018-01-01

Early detection of Alzheimer’s disease (AD) has been challenging as current biomarkers are invasive and costly. Strong predictors of future AD diagnosis include lower volume of the hippocampus and entorhinal cortex, as well as the ɛ4 allele of the Apolipoprotein E gene (APOE) gene. Therefore, studying functions that are critically mediated by the hippocampus and entorhinal cortex, such as spatial memory, in APOE ɛ4 allele carriers, may be key to the identification of individuals at risk of AD, prior to the manifestation of cognitive impairments. Using a virtual navigation task developed in-house, specifically designed to assess spatial versus non-spatial strategies, the current study is the first to differentiate functional and structural differences within APOE ɛ4 allele carriers. APOE ɛ4 allele carriers that predominantly use non-spatial strategies have decreased fMRI activity in the hippocampus and increased atrophy in the hippocampus, entorhinal cortex, and fimbria compared to APOE ɛ4 allele carriers who use spatial strategies. In contrast, APOE ɛ4 allele carriers who use spatial strategies have grey matter levels comparable to non-APOE ɛ4 allele carriers. Furthermore, in a leave-one-out analysis, grey matter in the entorhinal cortex could predict navigational strategy with 92% accuracy. PMID:29278888

Healthy versus Entorhinal Cortical Atrophy Identification in Asymptomatic APOE4 Carriers at Risk for Alzheimer's Disease.

PubMed

Konishi, Kyoko; Joober, Ridha; Poirier, Judes; MacDonald, Kathleen; Chakravarty, Mallar; Patel, Raihaan; Breitner, John; Bohbot, Véronique D

2018-01-01

Early detection of Alzheimer's disease (AD) has been challenging as current biomarkers are invasive and costly. Strong predictors of future AD diagnosis include lower volume of the hippocampus and entorhinal cortex, as well as the ɛ4 allele of the Apolipoprotein E gene (APOE) gene. Therefore, studying functions that are critically mediated by the hippocampus and entorhinal cortex, such as spatial memory, in APOE ɛ4 allele carriers, may be key to the identification of individuals at risk of AD, prior to the manifestation of cognitive impairments. Using a virtual navigation task developed in-house, specifically designed to assess spatial versus non-spatial strategies, the current study is the first to differentiate functional and structural differences within APOE ɛ4 allele carriers. APOE ɛ4 allele carriers that predominantly use non-spatial strategies have decreased fMRI activity in the hippocampus and increased atrophy in the hippocampus, entorhinal cortex, and fimbria compared to APOE ɛ4 allele carriers who use spatial strategies. In contrast, APOE ɛ4 allele carriers who use spatial strategies have grey matter levels comparable to non-APOE ɛ4 allele carriers. Furthermore, in a leave-one-out analysis, grey matter in the entorhinal cortex could predict navigational strategy with 92% accuracy.

Experimental consideration of capillary chromatography based on tube radial distribution of ternary mixture carrier solvents under laminar flow conditions.

PubMed

Jinno, Naoya; Hashimoto, Masahiko; Tsukagoshi, Kazuhiko

2011-01-01

A capillary chromatography system has been developed based on the tube radial distribution of the carrier solvents using an open capillary tube and a water-acetonitrile-ethyl acetate mixture carrier solution. This tube radial distribution chromatography (TRDC) system works under laminar flow conditions. In this study, a phase diagram for the ternary mixture carrier solvents of water, acetonitrile, and ethyl acetate was constructed. The phase diagram that included a boundary curve between homogeneous and heterogeneous solutions was considered together with the component ratios of the solvents in the homogeneous carrier solutions required for the TRDC system. It was found that the TRDC system performed well with homogeneous solutions having component ratios of the solvents that were positioned near the homogeneous-heterogeneous solution boundary of the phase diagram. For preparing the carrier solutions of water-hydrophilic/hydrophobic organic solvents for the TRDC system, we used for the first time methanol, ethanol, 1,4-dioxane, and 1-propanol, instead of acetonitrile (hydrophilic organic solvent), as well as chloroform and 1-butanol, instead of ethyl acetate (hydrophobic organic solvent). The homogeneous ternary mixture carrier solutions were prepared near the homogeneous-heterogeneous solution boundary. Analyte mixtures of 2,6-naphthalenedisulfonic acid and 1-naphthol were separated with the TRDC system using these homogeneous ternary mixture carrier solutions. The pressure change in the capillary tube under laminar flow conditions might alter the carrier solution from homogeneous in the batch vessel to heterogeneous, thus affecting the tube radial distribution of the solvents in the capillary tube.

Modeling of photocurrent and lag signals in amorphous selenium x-ray detectors

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

Siddiquee, Sinchita; Kabir, M. Z., E-mail: kabir@encs.concordia.ca

2015-07-15

A mathematical model for transient photocurrent and lag signal in x-ray imaging detectors has been developed by considering charge carrier trapping and detrapping in the energy distributed defect states under exponentially distributed carrier generation across the photoconductor. The model for the transient and steady-state carrier distributions and hence the photocurrent has been developed by solving the carrier continuity equation for both holes and electrons. The residual (commonly known as lag signal) current is modeled by solving the trapping rate equations considering the thermal release and trap filling effects. The model is applied to amorphous selenium (a-Se) detectors for both chestmore » radiography and mammography. The authors analyze the dependence of the residual current on various factors, such as x-ray exposure, applied electric field, and temperature. The electron trapping and detrapping mostly determines the residual current in a-Se detectors. The lag signal is more prominent in chest radiographic detector than in mammographic detectors. The model calculations are compared with the published experimental data and show a very good agreement.« less

[Advances in novel carrier systems of chemical constituents from spice volatile oils].

PubMed

Zhang, Jia-jia; Zhu, Yuan; Yu, Jiang-nan; Xu, Xi-ming

2015-10-01

Recent years, chemical constituents from spice volatile oils have gained worldwide concern owing to its multiple pharmacological effects and safety for using as the natural antibacterial agents. However, their poor dissolution, strong volatility, serious irritation, weak stability, easy oxidation and low bioavailability characteristics are the major obstacle in the preparation of effective oral formulation and practical application. Therefore, there is an urgent need to select a novel carrier system that can delivery the chemical constituents from spice volatile oils more efficiently with improving their stability as well as alleviating the irritation, and develop the functional food, health products and even medicine for exerting their pharmacological effects, which also is the focus and nodus of the research on their application. This review presents recent systematic studies on their novel carrier systems, including cyclodextrin inclusion complex, liposomes, nanoemulsions, nanoparticles, solid dispersion and so on, and summarizes the characteristics, application range and problems of each novel carrier systems, in order to provide some beneficial thoughts in further developing new products of chemical constituents from spice volatile oils.

Multiphysics modeling of non-linear laser-matter interactions for optically active semiconductors

NASA Astrophysics Data System (ADS)

Kraczek, Brent; Kanp, Jaroslaw

Development of photonic devices for sensors and communications devices has been significantly enhanced by computational modeling. We present a new computational method for modelling laser propagation in optically-active semiconductors within the paraxial wave approximation (PWA). Light propagation is modeled using the Streamline-upwind/Petrov-Galerkin finite element method (FEM). Material response enters through the non-linear polarization, which serves as the right-hand side of the FEM calculation. Maxwell's equations for classical light propagation within the PWA can be written solely in terms of the electric field, producing a wave equation that is a form of the advection-diffusion-reaction equations (ADREs). This allows adaptation of the computational machinery developed for solving ADREs in fluid dynamics to light-propagation modeling. The non-linear polarization is incorporated using a flexible framework to enable the use of multiple methods for carrier-carrier interactions (e.g. relaxation-time-based or Monte Carlo) to enter through the non-linear polarization, as appropriate to the material type. We demonstrate using a simple carrier-carrier model approximating the response of GaN. Supported by ARL Materials Enterprise.

A novel nano-carrier transdermal gel against inflammation.

PubMed

Chaudhary, Hema; Kohli, Kanchan; Kumar, Vikash

2014-04-25

The objective was to develop a stable, reproducible and patient non-infringing novel transdermal drug delivery system "nano-carrier transdermal gel" (NCTG) in combination of partial dose replacement of diclofenac diethylamine (DDEA) by curcumin (CRM). The drug content of gel was 99.30 and 97.57% for DDEA and CRM. Plasma samples were analyzed by liquid chromatography with triple-quadrupole tandem mass spectrometer (LC-MS/MS). Data were integrated with Analyst™ and analyzed by WinNonlin; stability parameters were analyzed using Tukey-Kramer multiple comparison test. Its average skin irritation scored 0.49 concluded to be non-irritant, safe for human use and in vivo studies revealed significantly greater extent of absorption and highly significant inhibition (%) of carrageenan induced paw edema. The results also demonstrated that encapsulation of drugs in nano-carrier increases its biological activity due to superior skin penetration potential. Hence, a novel once day transdermal gel of nano-carrier (nano-transfersomes; deformable vesicular) is achieved, to increase systemic availability, subsequent reduction in dose and toxicity of DDEA was developed for the treatment of inflammation. Copyright © 2014 Elsevier B.V. All rights reserved.

Caregiving and 5-HTTLPR Genotype Predict Adolescent Physiological Stress Reactivity: Confirmatory Tests of Gene × Environment Interactions.

PubMed

Sumner, Jennifer A; McLaughlin, Katie A; Walsh, Kate; Sheridan, Margaret A; Koenen, Karestan C

2015-03-03

A theory-driven confirmatory approach comparing diathesis-stress and differential susceptibility models of Gene × Environment (G × E) interactions was applied to examine whether 5-HTTLPR genotype moderated the effect of early maternal caregiving on autonomic nervous system (ANS) stress reactivity in 113 adolescents aged 13-17 years. Findings supported a differential susceptibility, rather than diathesis-stress, framework. Carriers of one or more 5-HTTLPR short alleles (SS/SL carriers) reporting higher quality caregiving exhibited approach ANS responses to a speech task, whereas those reporting lower quality caregiving exhibited withdrawal ANS responses. Carriers of two 5-HTTLPR long alleles (LL carriers) were unaffected by caregiving. Findings suggest that 5-HTTLPR genotype and early caregiving in interaction are associated with ANS stress reactivity in adolescents in a "for better and for worse" fashion, and they demonstrate the promise of confirmatory methods for testing G × E interactions. © 2015 The Authors. Child Development © 2015 Society for Research in Child Development, Inc.

Final Report: Hot Carrier Collection in Thin Film Silicon with Tailored Nanocrystalline/Amorphous Structure

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

Collins, Reuben T.

This project developed, characterized, and perfected a new type of highly tunable nanocrystalline silicon (nc-Si:H) incorporating quantum confined silicon nanoparticles (SiNPs). A dual zone deposition process and system were developed and demonstrated. The depositions of SiNPs, the amorphous phase, and co-deposited material were characterized and optimized. Material design and interpretation of results were guided by new theoretical tools that examined both the electronic structure and carrier dynamics of this hybrid material. Heterojunction and p-i-n solar cells were demonstrated and characterized. Photo-thin-film-transistors allowed mobility to be studied as a function SiNP density in the films. Rapid (hot) transfer of carriers frommore » the amorphous matrix to the quantum confined SiNPs was observed and connected to reduced photo-degradation. The results carry quantum confined Si dots from a novelty to materials that can be harnessed for PV and optoelectronic applications. The growth process is broadly extendable with alternative amorphous matrices, novel layered structures, and alternative NPs easily accessible. The hot carrier effects hold the potential for third generation photovoltaics.« less

Bias stress in PDI-CN2 and P3HT studied with Kelvin Probe Force Microscopy

NASA Astrophysics Data System (ADS)

Cao, Minxuan; Moscatello, Jason; Castaneda, Chloe; Xue, Binglan; Usluer, Ozlem; Briseno, Alejandro; Aidala, Katherine

We have developed a technique that uses scanning probe microscopy (SPM) to study the real-time injection and extraction of charge carriers in organic semiconductor devices. We investigate PDI-CN2 and P3HT in a back gate field effect transistor geometry with gold electrodes. By positioning the SPM tip at an individual location and using Kelvin probe microscopy to record the potential over time, we can record how the charge carriers respond to changing the gate voltage while the source and drain electrodes are grounded. We see relatively fast screening when carriers are injected into the film. The screening is slower when carriers must escape from traps to exit the film. By incrementally stepping the gate voltage, we can probe different trap depths. By repeating the measurement, we observe the development of longer lived trap states, shown by the longer time recorded to fully screen the gate voltage. This work is supported by NSF Grant DMR-0955348, and the Center for Heirarchical Manufacturing at the University of Massachusetts, Amherst (NSF CMMI-1025020).

Descriptive epidemiology of upper respiratory disease and associated risk factors in cats in an animal shelter in coastal western Canada

PubMed Central

Gourkow, Nadine; Lawson, James H.; Hamon, Sara C.; Phillips, Clive J.C.

2013-01-01

We examined 250 cats at an animal shelter in the coastal temperate region of Canada to determine whether age, source, gender, and sterilization status influenced risk of shedding at intake, transmission of infection, and development of clinical upper respiratory disease (URD). On admission, 28% of the cats were positive for 1 or more infectious agent related to URD; 21% were carriers of Mycoplasma felis and < 3% were carriers of feline calicivirus (FCV), feline herpesvirus-1 (FHV-1) or Bordetella bronchiseptica. Chlamydophila felis and H1N1 influenza virus were not detected. Carrier status was not affected by source, gender, sterilization status, or age (P > 0.05). Viral and bacterial shedding increased by 9% and 11%, respectively, over 3 sampling times (days 1, 4, and 10). Over 40 days after admission, the cumulative probability of developing URD was 2.2 times greater for stray than owner-surrendered cats (P = 0.02) and 0.5 times as great for neutered cats as for intact cats (P = 0.03). Cats that were shedding at intake were 2.6 times more likely to develop URD than were non-carriers (P < 0.002). Cats with FHV-1 and B. bronchiseptica infections were most at risk compared with non-shedding cats (P < 0.01). PMID:23904635

DRD4 Polymorphism Moderates the Effect of Alcohol Consumption on Social Bonding

PubMed Central

Creswell, Kasey G.; Sayette, Michael A.; Manuck, Stephen B.; Ferrell, Robert E.; Hill, Shirley Y.; Dimoff, John D.

2012-01-01

Development of interpersonal relationships is a fundamental human motivation, and behaviors facilitating social bonding are prized. Some individuals experience enhanced reward from alcohol in social contexts and may be at heightened risk for developing and maintaining problematic drinking. We employed a 3 (group beverage condition) ×2 (genotype) design (N = 422) to test the moderating influence of the dopamine D4 receptor gene (DRD4 VNTR) polymorphism on the effects of alcohol on social bonding. A significant gene x environment interaction showed that carriers of at least one copy of the 7-repeat allele reported higher social bonding in the alcohol, relative to placebo or control conditions, whereas alcohol did not affect ratings of 7-absent allele carriers. Carriers of the 7-repeat allele were especially sensitive to alcohol's effects on social bonding. These data converge with other recent gene-environment interaction findings implicating the DRD4 polymorphism in the development of alcohol use disorders, and results suggest a specific pathway by which social factors may increase risk for problematic drinking among 7-repeat carriers. More generally, our findings highlight the potential utility of employing transdisciplinary methods that integrate genetic methodologies, social psychology, and addiction theory to improve theories of alcohol use and abuse. PMID:22347363

DRD4 polymorphism moderates the effect of alcohol consumption on social bonding.

PubMed

Creswell, Kasey G; Sayette, Michael A; Manuck, Stephen B; Ferrell, Robert E; Hill, Shirley Y; Dimoff, John D

2012-01-01

Development of interpersonal relationships is a fundamental human motivation, and behaviors facilitating social bonding are prized. Some individuals experience enhanced reward from alcohol in social contexts and may be at heightened risk for developing and maintaining problematic drinking. We employed a 3 (group beverage condition) ×2 (genotype) design (N = 422) to test the moderating influence of the dopamine D4 receptor gene (DRD4 VNTR) polymorphism on the effects of alcohol on social bonding. A significant gene x environment interaction showed that carriers of at least one copy of the 7-repeat allele reported higher social bonding in the alcohol, relative to placebo or control conditions, whereas alcohol did not affect ratings of 7-absent allele carriers. Carriers of the 7-repeat allele were especially sensitive to alcohol's effects on social bonding. These data converge with other recent gene-environment interaction findings implicating the DRD4 polymorphism in the development of alcohol use disorders, and results suggest a specific pathway by which social factors may increase risk for problematic drinking among 7-repeat carriers. More generally, our findings highlight the potential utility of employing transdisciplinary methods that integrate genetic methodologies, social psychology, and addiction theory to improve theories of alcohol use and abuse.

Risk of breast cancer after a diagnosis of ovarian cancer in BRCA mutation carriers: Is preventive mastectomy warranted?

PubMed

McGee, Jacob; Giannakeas, Vasily; Karlan, Beth; Lubinski, Jan; Gronwald, Jacek; Rosen, Barry; McLaughlin, John; Risch, Harvey; Sun, Ping; Foulkes, William D; Neuhausen, Susan L; Kotsopoulos, Joanne; Narod, Steven A

2017-05-01

Preventive breast surgery and MRI screening are offered to unaffected BRCA mutation carriers. The clinical benefit of these two modalities has not been evaluated among mutation carriers with a history of ovarian cancer. Thus, we sought to determine whether or not BRCA mutation carriers with ovarian cancer would benefit from preventive mastectomy or from MRI screening. First, the annual mortality rate for ovarian cancer patients was estimated for a cohort of 178 BRCA mutation carriers from Ontario, Canada. Next, the actuarial risk of developing breast cancer was estimated using an international registry of 509 BRCA mutation carriers with ovarian cancer. A series of simulations was conducted to evaluate the reduction in the probability of death (from all causes) associated with mastectomy and with MRI-based breast surveillance. Cox proportional hazards models were used to evaluate the impacts of mastectomy and MRI screening on breast cancer incidence as well as on all-cause mortality. Twenty (3.9%) of the 509 patients developed breast cancer within ten years following ovarian cancer diagnosis. The actuarial risk of developing breast cancer at ten years post-diagnosis, conditional on survival from ovarian cancer and other causes of mortality was 7.8%. Based on our simulation results, among all BRCA mutation-carrying patients diagnosed with stage III/IV ovarian cancer at age 50, the chance of dying before age 80 was reduced by less than 1% with MRI and by less than 2% with mastectomy. Greater improvements in survival with MRI or mastectomy were observed for women who had already survived 10years after ovarian cancer, and for women with stage I or II ovarian cancer. Among BRCA mutation-carrying ovarian cancer patients without a personal history of breast cancer, neither preventive mastectomy nor MRI screening is warranted, except for those who have survived ovarian cancer without recurrence for ten years and for those with early stage ovarian cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

Spectroscopy of Charge Carriers and Traps in Field-Doped Single Crystal Organic Semiconductors

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

Zhu, Xiaoyang

2014-12-10

The proposed research aims to achieve quantitative, molecular level understanding of charge carriers and traps in field-doped crystalline organic semiconductors via in situ linear and nonlinear optical spectroscopy, in conjunction with transport measurements and molecular/crystal engineering. Organic semiconductors are emerging as viable materials for low-cost electronics and optoelectronics, such as organic photovoltaics (OPV), organic field effect transistors (OFETs), and organic light emitting diodes (OLEDs). Despite extensive studies spanning many decades, a clear understanding of the nature of charge carriers in organic semiconductors is still lacking. It is generally appreciated that polaron formation and charge carrier trapping are two hallmarks associatedmore » with electrical transport in organic semiconductors; the former results from the low dielectric constants and weak intermolecular electronic overlap while the latter can be attributed to the prevalence of structural disorder. These properties have lead to the common observation of low charge carrier mobilities, e.g., in the range of 10-5 - 10-3 cm2/Vs, particularly at low carrier concentrations. However, there is also growing evidence that charge carrier mobility approaching those of inorganic semiconductors and metals can exist in some crystalline organic semiconductors, such as pentacene, tetracene and rubrene. A particularly striking example is single crystal rubrene (Figure 1), in which hole mobilities well above 10 cm2/Vs have been observed in OFETs operating at room temperature. Temperature dependent transport and spectroscopic measurements both revealed evidence of free carriers in rubrene. Outstanding questions are: what are the structural features and physical properties that make rubrene so unique? How do we establish fundamental design principles for the development of other organic semiconductors of high mobility? These questions are critically important but not comprehensive, as the nature of charge carriers is known to evolve as the carrier concentration increases, due to the presence of intrinsic disorder in organic semiconductors. Thus, a complementary question is: how does the nature of charge transport change as a function of carrier concentration?« less

Effect of PEGylation on ligand-based targeting of drug carriers to the vascular wall in blood flow.

PubMed

Onyskiw, Peter J; Eniola-Adefeso, Omolola

2013-09-03

The blood vessel wall plays a prominent role in the development of many life-threatening diseases and as such is an attractive target for treatment. To target diseased tissue, particulate drug carriers often have their surfaces modified with antibodies or epitopes specific to vascular wall-expressed molecules, along with poly(ethylene glycol) (PEG) to improve carrier blood circulation time. However, little is known about the effect of poly(ethylene glycol) on carrier adhesion dynamics-specifically in blood flow. Here we examine the influence of different molecular weight PEG spacers on particle adhesion in blood flow. Anti-ICAM-1 or Sialyl Lewis(a) were grafted onto polystyrene 2 μm and 500 nm spheres via PEG spacers and perfused in blood over activated endothelial cells at physiological shear conditions. PEG spacers were shown to improve, reduce, or have no effect on the binding density of targeted-carriers depending on the PEG surface conformation, shear rate, and targeting moiety.

Lighter-Than-Air (LTA) "AirStation": Unmanned Aircraft System (UAS) Carrier Concept

NASA Technical Reports Server (NTRS)

Hochstetler, Ronald D.; Bosma, John; Chachad, Girish H.; Blanken, Matthew L.

2016-01-01

The advantages of utilizing an airship as an airborne carrier for support and deployment of Unmanned Aircraft Systems (UAS) are examined. Whether as a stand-alone platform or in concert with conventional aircraft, the airship UAS carrier provides a number of compelling benefits for both military and civilian missions. As a mobile base it can remain operational despite political fallout that may render ground or ocean based UAS sites unavailable. It offers the psychological impact of a power projection tool that has few geographical limits, and holds promise as a new method for cost-saving intelligence gathering. It is also adaptable for civilian variants for supporting: emergency response, security/surveillance, delivery of medical/food supplies, as well as commercial package delivery to metropolitan and remote communities. This paper presents the background on airship-aircraft operations, and explores the general airship carrier concept. Additionally, a catalog of contemporary technologies available to support the airship carrier concept are discussed, and essential elements for an Air-Station Development program proposed.

Development of self-healing polymers via amine-epoxy chemistry: I. Properties of healing agent carriers and the modelling of a two-part self-healing system

NASA Astrophysics Data System (ADS)

Zhang, He; Yang, Jinglei

2014-06-01

Two types of healing agent carriers (microcapsules containing epoxy solution, referred to as EP-capsules, and etched hollow glass bubbles (HGBs) loaded with amine solution, referred to as AM-HGBs) used in self-healing epoxy systems were prepared and characterized in this study. The core percentages were measured at about 80 wt% and 33 wt% for EP-capsules and AM-HGBs, respectively. The loaded amine in AM-HGB, after incorporation into the epoxy matrix, showed high stability at ambient temperature, but diffused out gradually during heat treatment at 80 °C. The amount and the mass ratio of the two released healants at the crack plane were correlated with the size, concentration, and core percentage of the healing agent carriers. A simplified cubic array model for randomly distributed healing agent carriers was adopted to depict the longest diffusion distance of the released healants, which is inversely proportional to the cubic root of the carrier concentration.

The Use of Synthetic Carriers in Malaria Vaccine Design

PubMed Central

Powles, Liam; Xiang, Sue D.; Selomulya, Cordelia; Plebanski, Magdalena

2015-01-01

Malaria vaccine research has been ongoing since the 1980s with limited success. However, recent improvements in our understanding of the immune responses required to combat each stage of infection will allow for intelligent design of both antigens and their associated delivery vaccine vehicles/vectors. Synthetic carriers (also known as vectors) are usually particulate and have multiple properties, which can be varied to control how an associated vaccine interacts with the host, and consequently how the immune response develops. This review comprehensively analyzes both historical and recent studies in which synthetic carriers are used to deliver malaria vaccines. Furthermore, the requirements for a synthetic carrier, such as size, charge, and surface chemistry are reviewed in order to understand the design of effective particle-based vaccines against malaria, as well as providing general insights. Synthetic carriers have the ability to alter and direct the immune response, and a better control of particle properties will facilitate improved vaccine design in the near future. PMID:26529028

A Comparison of Photocatalytic Activities of Gold Nanoparticles Following Plasmonic and Interband Excitation and a Strategy for Harnessing Interband Hot Carriers for Solution Phase Photocatalysis

PubMed Central

2017-01-01

Light driven excitation of gold nanoparticles (GNPs) has emerged as a potential strategy to generate hot carriers for photocatalysis through excitation of localized surface plasmon resonance (LSPR). In contrast, carrier generation through excitation of interband transitions remains a less explored and underestimated pathway for photocatalytic activity. Photoinduced oxidative etching of GNPs with FeCl3 was investigated as a model reaction in order to elucidate the effects of both types of transitions. The quantitative results show that interband transitions more efficiently generate hot carriers and that those carriers exhibit higher reactivity as compared to those generated solely by LSPR. Further, leveraging the strong π-acidic character of the resulting photogenerated Au+ hole, an interband transition induced cyclization reaction of alkynylphenols was developed. Notably, alkyne coordination to the Au+ hole intercepts the classic oxidation event and leads to the formation of the catalytically active gold clusters on subnanometer scale. PMID:28573211

Self-consistent Monte Carlo study of high-field carrier transport in graded heterostructures

NASA Astrophysics Data System (ADS)

Al-Omar, A.; Krusius, J. P.

1987-11-01

Hot-electron transport over graded heterostructures was investigated. A new formulation of the carrier transport, based on the effective mass theorem, a position-dependent Hamiltonian, scattering rates that included overlap integrals with correct symmetry, and ohmic contact models preserving the stochastic nature of carrier injection, was developed and implemented into the self-consistent ensemble Monte Carlo method. Hot-carrier transport in a graded Al(x)Ga(1-x)As device was explored with the following results: (1) the transport across compositionally graded semiconductor structures cannot be described with drift and diffusion concepts; (2) although heterostructure launchers generate a ballistic electron fraction as high as 15 percent and 40 percent of the total electron population for 300 and 77 K, respectively, they simultaneously reduce macroscopic average currents and carrier velocities; and (3) the width of the ballistic electron distribution and the magnitude of the ballistic fraction are primarily determined by material parameters and operating voltages rather than details of the device structure.

Characteristics of NO cycle coupling with urea cycle in non-hyperammonemic carriers of ornithine transcarbamylase deficiency.

PubMed

Nagasaka, Hironori; Yorifuji, Tohru; Egawa, Hiroto; Inui, Ayano; Fujisawa, Tomoo; Komatsu, Haruki; Tsukahara, Hirokazu; Uemoto, Shinji; Inomata, Yukihiro

2013-07-01

Urea cycle deficient patients with prominent hyperammonemic often exhibit abnormal production of nitric oxide (NO), which reduces vascular tone, along with amino acid abnormalities. However, information related to the metabolic changes in heterozygotes of ornithine transcarbamylase deficiency (OTCD) lacking overt hyperammonemia is quite limited. We examined vascular mediators and amino acids in non-hyperammonemic heterozygotes. Twenty-four heterozygous OTCD adult females without hyperammonemic bouts, defined as non-hyperammonemic carriers, were enrolled. We measured blood amino acids constituting urea cycle and nitric oxide (NO) cycle. Blood concentrations of nitrate/nitrite (NOx) as stable NO-metabolites, asymmetric dimethylarginine (ADMA) inhibiting NO synthesis, and endothelin-1 (ET-1) raising vascular tone were also determined. NOx concentrations were significantly lower in non-hyperammonemic carriers (p < 0.01). However, ADMA and ET-1 levels in this group were comparable to those in the age-matched control group. Arginine and citrulline levels were also significantly lower in non-hyperammonemic carriers than in controls (p < 0.01). Of the 24 non-hyperammonemic carriers, 10 often developed headaches. Their daily NOx and arginine levels were significantly lower than those in headache-free carriers (p < 0.05). In three carriers receiving oral l-arginine, blood NOx concentrations were significantly higher. In two of those three, the occurrence of headaches was decreased. These results suggest that NO cycle coupling with the urea cycle is altered substantially even in non-hyperammonemic OTCD carriers, predisposing them to headaches. Copyright © 2013 Elsevier Inc. All rights reserved.

Enhanced solubility of piperine using hydrophilic carrier-based potent solid dispersion systems.

PubMed

Thenmozhi, Kathavarayan; Yoo, Young Je

2017-09-01

Piperine alkaloid, an important constituent of black pepper, exhibits numerous therapeutic properties, whereas its usage as a drug is limited due to its poor solubility in aqueous medium, which leads to poor bioavailability. Herein, a new method has been developed to improve the solubility of this drug based on the development of solid dispersions with improved dissolution rate using hydrophilic carriers such as sorbitol (Sor), polyethylene glycol (PEG) and polyvinyl pyrrolidone K30 (PVP) by solvent method. Physical mixtures of piperine and carriers were also prepared for comparison. The physicochemical properties of the prepared solid dispersions were examined using SEM, TEM, DSC, XRD and FT-IR. In vitro dissolution profile of the solid dispersions was recorded and compared with that of the pure piperine and physical mixtures. The effect of these carriers on the aqueous solubility of piperine has been investigated. The solid dispersions of piperine with Sor, PEG and PVP exhibited superior performance for the dissolution of piperine with a drug release of 70%, 76% and 89%, respectively after 2 h compared to physical mixtures and pure piperine, which could be due to its transformation from crystalline to amorphous form as well as the attachment of hydrophilic carriers to the surface of poorly water-soluble piperine. Results suggest that the piperine solid dispersions prepared with improved in vitro release exhibit potential advantage in delivering poorly water-soluble piperine as an oral supplement.

Breast cancer risks and risk prediction models.

PubMed

Engel, Christoph; Fischer, Christine

2015-02-01

BRCA1/2 mutation carriers have a considerably increased risk to develop breast and ovarian cancer. The personalized clinical management of carriers and other at-risk individuals depends on precise knowledge of the cancer risks. In this report, we give an overview of the present literature on empirical cancer risks, and we describe risk prediction models that are currently used for individual risk assessment in clinical practice. Cancer risks show large variability between studies. Breast cancer risks are at 40-87% for BRCA1 mutation carriers and 18-88% for BRCA2 mutation carriers. For ovarian cancer, the risk estimates are in the range of 22-65% for BRCA1 and 10-35% for BRCA2. The contralateral breast cancer risk is high (10-year risk after first cancer 27% for BRCA1 and 19% for BRCA2). Risk prediction models have been proposed to provide more individualized risk prediction, using additional knowledge on family history, mode of inheritance of major genes, and other genetic and non-genetic risk factors. User-friendly software tools have been developed that serve as basis for decision-making in family counseling units. In conclusion, further assessment of cancer risks and model validation is needed, ideally based on prospective cohort studies. To obtain such data, clinical management of carriers and other at-risk individuals should always be accompanied by standardized scientific documentation.

Quantitative determination of optical and recombination losses in thin-film photovoltaic devices based on external quantum efficiency analysis

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

Nakane, Akihiro; Tamakoshi, Masato; Fujimoto, Shohei

2016-08-14

In developing photovoltaic devices with high efficiencies, quantitative determination of the carrier loss is crucial. In conventional solar-cell characterization techniques, however, photocurrent reduction originating from parasitic light absorption and carrier recombination within the light absorber cannot be assessed easily. Here, we develop a general analysis scheme in which the optical and recombination losses in submicron-textured solar cells are evaluated systematically from external quantum efficiency (EQE) spectra. In this method, the optical absorption in solar cells is first deduced by imposing the anti-reflection condition in the calculation of the absorptance spectrum, and the carrier extraction from the light absorber layer ismore » then modeled by considering a carrier collection length from the absorber interface. Our analysis method is appropriate for a wide variety of photovoltaic devices, including kesterite solar cells [Cu{sub 2}ZnSnSe{sub 4}, Cu{sub 2}ZnSnS{sub 4}, and Cu{sub 2}ZnSn(S,Se){sub 4}], zincblende CdTe solar cells, and hybrid perovskite (CH{sub 3}NH{sub 3}PbI{sub 3}) solar cells, and provides excellent fitting to numerous EQE spectra reported earlier. Based on the results obtained from our EQE analyses, we discuss the effects of parasitic absorption and carrier recombination in different types of solar cells.« less

Neuropsychological Deficits in Huntington’s Disease Gene Carriers and Correlates of Early “Conversion”

PubMed Central

Brandt, Jason; Inscore, Anjeli B.; Ward, Julianna; Shpritz, Barnett; Rosenblatt, Adam; Margolis, Russell L.; Ross, Christopher A.

2010-01-01

The authors examined whether the baseline cognitive functioning of 21 clinically normal huntingtin mutation carriers who developed manifest Huntington’s disease on follow-up differed from that of 49 mutation carriers who remain asymptomatic over the same period in a longitudinal study. One hundred thirty-four gene-negative offspring of Huntington’s disease patients were studied as well. Overall, there were no differences in cognitive test performance among the three groups. However, “converters” who developed signs of Huntington’s disease within 8.6 years demonstrated poorer performance on the Wisconsin Card Sorting Test at baseline. People with the Huntington’s disease mutation who are carefully examined neurologically and found to be asymptomatic have, at most, very minimal problem-solving impairment, and only if they are within a few years of clinical onset. PMID:19196932

Development of a Dew-Point Generator for Gases Other than Air and Nitrogen and Pressures up to 6 MPa

NASA Astrophysics Data System (ADS)

Bosma, R.; Peruzzi, A.

2012-09-01

A new primary humidity standard is currently being developed at VSL that, in addition to ordinary operation with air and nitrogen at atmospheric pressure, can be operated also with special carrier gases such as natural gas and SF6 and at pressures up to 6 MPa. In this paper, the design and construction of this new primary dew-point generator and the preliminary tests performed on the generator are reported. The results of the first efficiency tests, performed for the dew-point temperature range from -50 °C to 20°C, for pressures up to 0.7MPa and for carrier gas flow rates up to 4L· min-1, showed satisfactory generator performance when used in the single-pass mode, i.e., with no recirculation of the carrier gas.

Characterization of two acyl-acyl carrier protein thioesterases from developing Cuphea seeds specific for medium-chain- and oleoyl-acyl carrier protein.

PubMed

Dörmann, P; Spener, F; Ohlrogge, J B

1993-03-01

Two acyl-acyl carrier protein (ACP) thioesterases were partially purified from developing seeds of Cuphea lanceolata Ait., a plant with decanoic acid-rich triacylglycerols. The two enzymes differ markedly in their substrate specificity. One is specific for medium-chain acyl-ACPs, the other one for oleoyl-ACP. In addition, these enzymes are distinct with regard to molecular weight, pH optimum and sensitivity to salt. The thioesterases could be separated by Mono Q chromatography or gel filtration. The medium-chain acyl-ACP thioesterase and oleoyl-ACP thioesterase were purified from a crude extract 29- and 180-fold, respectively. In Cuphea wrightii A. Gray, which predominantly contains decanoic a nd lauric acid in the seeds, two different thioesterases were also found with a similar substrate specificity as in Cuphea lanceolata.

Viruses - from pathogens to vaccine carriers.

PubMed

Small, Juliana C; Ertl, Hildegund C J

2011-10-01

Vaccination is mankind's greatest public health success story. By now vaccines to many of the viruses that once caused fatal childhood diseases are routinely used throughout the world. Traditional methods of vaccine development through inactivation or attenuation of viruses have failed for some of the most deadly human pathogens, necessitating new approaches. Genetic modification of viruses not only allows for their attenuation but also for incorporation of sequences from other viruses, turning one pathogen into a vaccine carrier for another. Recombinant viruses have pros and cons as vaccine carriers, as discussed below using vectors based on adenovirus, herpesvirus, flavivirus, and rhabdovirus as examples.

Photoconductivity response time in amorphous semiconductors

NASA Astrophysics Data System (ADS)

Adriaenssens, G. J.; Baranovskii, S. D.; Fuhs, W.; Jansen, J.; Öktü, Ö.

1995-04-01

The photoconductivity response time of amorphous semiconductors is examined theoretically on the basis of standard definitions for free- and trapped-carrier lifetimes, and experimentally for a series of a-Si1-xCx:H alloys with x<0.1. Particular attention is paid to its dependence on carrier generation rate and temperature. As no satisfactory agreement between models and experiments emerges, a simple theory is developed that can account for the experimental observations on the basis of the usual multiple-trappping ideas, provided a small probability of direct free-carrier recombination is included. The theory leads to a stretched-exponential photocurrent decay.

Quantum dynamics of nuclear spins and spin relaxation in organic semiconductors

NASA Astrophysics Data System (ADS)

Mkhitaryan, V. V.; Dobrovitski, V. V.

2017-06-01

We investigate the role of the nuclear-spin quantum dynamics in hyperfine-induced spin relaxation of hopping carriers in organic semiconductors. The fast-hopping regime, when the carrier spin does not rotate much between subsequent hops, is typical for organic semiconductors possessing long spin coherence times. We consider this regime and focus on a carrier random-walk diffusion in one dimension, where the effect of the nuclear-spin dynamics is expected to be the strongest. Exact numerical simulations of spin systems with up to 25 nuclear spins are performed using the Suzuki-Trotter decomposition of the evolution operator. Larger nuclear-spin systems are modeled utilizing the spin-coherent state P -representation approach developed earlier. We find that the nuclear-spin dynamics strongly influences the carrier spin relaxation at long times. If the random walk is restricted to a small area, it leads to the quenching of carrier spin polarization at a nonzero value at long times. If the random walk is unrestricted, the carrier spin polarization acquires a long-time tail, decaying as 1 /√{t } . Based on the numerical results, we devise a simple formula describing the effect quantitatively.

Cousin marriage and premarital carrier matching in a Bedouin community in Israel: attitudes, service development and educational intervention.

PubMed

Raz, Aviad E; Atar, Marcela

2004-01-01

Premarital carrier matching is a form of genetic counselling in which two individuals are told, if both are carriers, that they have a 25% risk at each pregnancy of having a child affected by the disease for which they were tested. If only one individual is a carrier this information is not disclosed. This scheme is offered to a consanguineous Bedouin community characterised by high prevalence of genetic diseases and a religious ban on abortion. To elicit attitudes of community members concerning cousin marriage and genetic counselling. Semi-structured interviews were conducted with Bedouin respondents (n = 49). Interviews revealed that a majority of Bedouin respondents confirmed the traditional and social role of cousin marriage. The main reasons given in this context were clan solidarity, interpersonal compatibility, preservation of family property, parental authority and social protection for women. A majority of the respondents also associated cousin marriage with genetic diseases. Regarding genetic testing, the majority of respondents preferred the option of premarital carrier matching, which was supposed to reduce stigmatisation, especially of women. Prenatal genetic testing was rejected on religious grounds. The result of this community-based and culture-sensitive process was a focus on premarital carrier matching.

Young Adult Female Fragile X Premutation Carriers Show Age- and Genetically-Modulated Cognitive Impairments

ERIC Educational Resources Information Center

Goodrich-Hunsaker, Naomi J.; Wong, Ling M.; McLennan, Yingratana; Srivastava, Siddharth; Tassone, Flora; Harvey, Danielle; Rivera, Susan M.; Simon, Tony J.

2011-01-01

The high frequency of the fragile X premutation in the general population and its emerging neurocognitive implications highlight the need to investigate the effects of the premutation on lifespan cognitive development. Until recently, cognitive function in fragile X premutation carriers (fXPCs) was presumed to be unaffected by the mutation. Here…

Terrain and landform influence on Tsuga canadensis (L.) Carriere (Eastern Hemlock) distribution in the southern Appalachian Mountains

Treesearch

G. Narayanaraj; P.V. Bolstad; K.J. Elliott; J.M. Vose

2010-01-01

We examined the relationships between hemlock distribution and abundance and terrain attributes for the Coweeta Basin in the southern Appalachian Mountains. Field measurements were combined with GIS mapping methods to develop predictive models of abundance and distribution of Tsuga canadensis (L.) Carriere (eastern hemlock) and evaluate the co-...

75 FR 18256 - Withdrawal of Proposed Improvements to the Motor Carrier Safety Status Measurement System...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... improved Carrier Safety Measurement System (CSMS) on November 30, 2010. The CSMS has been developed and...-2251. Mail: Docket Management Facility, U.S. Department of Transportation, Room W12-140, 1200 New...) Accident, (2) Driver, (3) Vehicle and (4) Safety Management. The four SEA values are then combined into an...

A flexible CPW package for a 30 GHz MMIC amplifier. [coplanar waveguide

NASA Technical Reports Server (NTRS)

Simons, Rainee N.; Taub, Susan R.

1992-01-01

A novel package, which consists of a carrier housing, has been developed for monolithic-millimeter wave Integrated Circuit amplifiers which operate at 30 giga-Hz. The carrier has coplanar waveguide (CPW) interconnects and provides heat-sinking, tuning, and cascading capabilities. The housing provides electrical isolation, mechanical protection and a feed-thru for biasing.

Separation of Olefin/Paraffin Mixtures with Carrier Facilitated Membrane Final Report

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

Merkel, T.C.; Blanc, R.; Zeid, J.

2007-03-12

This document describes the results of a DOE funded joint effort of Membrane Technology and Research Inc. (MTR), SRI International (SRI), and ABB Lummus (ABB) to develop facilitated transport membranes for olefin/paraffin separations. Currently, olefin/paraffin separation is done by distillation—an extremely energy-intensive process because of the low relative volatilities of olefins and paraffins. If facilitated transport membranes could be successfully commercialized, the potential energy savings achievable with this membrane technology are estimated to be 48 trillion Btu per year by the year 2020. We discovered in this work that silver salt-based facilitated transport membranes are not stable even in themore » presence of ideal olefin/paraffin mixtures. This decline in membrane performance appears to be caused by a previously unrecognized phenomenon that we have named olefin conditioning. As the name implies, this mechanism of performance degradation becomes operative once a membrane starts permeating olefins. This project is the first study to identify olefin conditioning as a significant factor impacting the performance of facilitated olefin transport membranes. To date, we have not identified an effective strategy to mitigate the impact of olefin conditioning. other than running at low temperatures or with low olefin feed pressures. In our opinion, this issue must be addressed before further development of facilitated olefin transport membranes can proceed. In addition to olefin conditioning, traditional carrier poisoning challenges must also be overcome. Light, hydrogen, hydrogen sulfide, and acetylene exposure adversely affect membrane performance through unwanted reaction with silver ions. Harsh poisoning tests with these species showed useful membrane lifetimes of only one week. These tests demonstrate a need to improve the stability of the olefin complexing agent to develop membranes with lifetimes satisfactory for commercial application. A successful effort to improve membrane coating solution stability resulted in the finding that membrane performance loss could be reversed for all poisoning cases except hydrogen sulfide exposure. This discovery offers the potential to extend membrane lifetime through cyclic regeneration. We also found that certain mixed carriers exhibited greater stability in reducing environments than exhibited by silver salt alone. These results offer promise that solutions to deal with carrier poisoning are possible. The main achievement of this program was the progress made in gaining a more complete understanding of the membrane stability challenges faced in the use of facilitated olefin transport membranes. Our systematic study of facilitated olefin transport uncovered the full extent of the stability challenge, including the first known identification of olefin conditioning and its impact on membrane development. We believe that significant additional fundamental research is required before facilitated olefin transport membranes are ready for industrial implementation. The best-case scenario for further development of this technology would be identification of a novel carrier that is intrinsically more stable than silver ions. If the stability problems could be largely circumvented by development of a new carrier, it would provide a clear breakthrough toward finally recognizing the potential of facilitated olefin transport. However, even if such a carrier is identified, additional development will be required to insure that the membrane matrix is a benign host for the olefin-carrier complexation reaction and shows good long-term stability.« less

Recovery Act: Novel Oxygen Carriers for Coal-fueled Chemical Looping

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

Pan, Wei-Ping; Cao, Yan

2012-11-30

Chemical Looping Combustion (CLC) could totally negate the necessity of pure oxygen by using oxygen carriers for purification of CO{sub 2} stream during combustion. It splits the single fuel combustion reaction into two linked reactions using oxygen carriers. The two linked reactions are the oxidation of oxygen carriers in the air reactor using air, and the reduction of oxygen carriers in the fuel reactor using fuels (i.e. coal). Generally metal/metal oxides are used as oxygen carriers and operated in a cyclic mode. Chemical looping combustion significantly improves the energy conversion efficiency, in terms of the electricity generation, because it improvesmore » the reversibility of the fuel combustion process through two linked parallel processes, compared to the conventional combustion process, which is operated far away from its thermo-equilibrium. Under the current carbon-constraint environment, it has been a promising carbon capture technology in terms of fuel combustion for power generation. Its disadvantage is that it is less mature in terms of technological commercialization. In this DOE-funded project, accomplishment is made by developing a series of advanced copper-based oxygen carriers, with properties of the higher oxygen-transfer capability, a favorable thermodynamics to generate high purity of CO{sub 2}, the higher reactivity, the attrition-resistance, the thermal stability in red-ox cycles and the achievement of the auto-thermal heat balance. This will be achieved into three phases in three consecutive years. The selected oxygen carriers with final-determined formula were tested in a scaled-up 10kW coal-fueled chemical looping combustion facility. This scaled-up evaluation tests (2-day, 8-hour per day) indicated that, there was no tendency of agglomeration of copper-based oxygen carriers. Only trace-amount of coke or carbon deposits on the copper-based oxygen carriers in the fuel reactor. There was also no evidence to show the sulphidization of oxygen carriers in the system by using the high-sulfur-laden asphalt fuels. In all, the scaled-up test in 10 kW CLC facility demonstrated that the preparation method of copper-based oxygen carrier not only help to maintain its good reactivity, also largely minimize its agglomeration tendency.« less

Reduced BRCA1 transcript levels in freshly isolated blood leukocytes from BRCA1 mutation carriers is mutation specific.

PubMed

Chehade, Rania; Pettapiece-Phillips, Rachael; Salmena, Leonardo; Kotlyar, Max; Jurisica, Igor; Narod, Steven A; Akbari, Mohammad R; Kotsopoulos, Joanne

2016-08-17

BRCA1 mutation carriers face a high lifetime risk of developing both breast and ovarian cancer. Haploinsufficiency is thought to predispose these women to cancer by reducing the pool of available BRCA1 transcript and protein, thereby compromising BRCA1 function. Whether or not cancer-free BRCA1 mutation carriers have lower messenger (m)RNA transcript levels in peripheral blood leukocytes has not been evaluated. The primary aim of this study was to characterize an association between BRCA1 mutation status and BRCA1 mRNA leukocyte expression levels among healthy women with a BRCA1 mutation. RNA was extracted from freshly isolated peripheral blood leukocytes of 58 cancer-free, female participants (22 BRCA1 mutation carriers and 36 non-carriers). The expression levels of 236 cancer-associated genes, including BRCA1, were quantified using the Human Cancer Reference gene panel from the Nanostring Technologies nCounter Analysis System. Multivariate modeling demonstrated that carrying a BRCA1 mutation was the most significant predictor of BRCA1 mRNA levels. BRCA1 mRNA levels were significantly lower in BRCA1 mutation carriers compared to non-carriers (146.7 counts vs. 175.1 counts; P = 0.002). Samples with BRCA1 mutations within exon 11 had lower BRCA1 mRNA levels than samples with mutations within the 5' and 3' regions of the BRCA1 gene (122.1 counts vs. 138.9 and 168.6 counts, respectively; P = 0.003). Unsupervised hierarchical clustering of gene expression profiles from freshly isolated blood leukocytes revealed that BRCA1 mutation carriers cluster more closely with other BRCA1 mutation carriers than with BRCA1 wild-type samples. Moreover, a set of 17 genes (including BRCA1) previously shown to be involved in carcinogenesis, were differentially expressed between BRCA1 mutation carriers and non-carriers. Overall, these findings support the concept of BRCA1 haploinsufficiency wherein a specific mutation results in dosage-dependent alteration of BRCA1 at the transcriptional level. This study is the first to show a decrease in BRCA1 mRNA expression in freshly isolated blood leukocytes from healthy, unaffected BRCA1 mutation carriers.

Identification and characterization of major cat allergen Fel d 1 mimotopes on filamentous phage carriers.

PubMed

Luzar, Jernej; Molek, Peter; Šilar, Mira; Korošec, Peter; Košnik, Mitja; Štrukelj, Borut; Lunder, Mojca

2016-03-01

Cat allergy is one of the most prevalent allergies worldwide and can lead to the development of rhinitis and asthma. Thus far, only allergen extracts from natural sources have been used for allergen-specific immunotherapy. However, extracts and whole allergens in immunotherapy present an anaphylaxis risk. Identification of allergen epitopes or mimotopes has an important role in development of safe and effective allergen-specific immunotherapy. Moreover, with a suitable immunogenic carrier, the absence of sufficient immune response elicited by short peptides could be surmounted. In this study, we identified five structural mimotopes of the major cat allergen Fel d 1 by immunoscreening with random peptide phage libraries. The mimotopes were computationally mapped to the allergen surface, and their IgE reactivity was confirmed using sera from cat-allergic patients. Importantly, the mimotopes showed no basophil activation of the corresponding cat-allergic patients, which makes them good candidates for the development of hypoallergenic vaccine. As bacteriophage particles are becoming increasingly recognized as immunogenic carriers, we constructed bacteriophage particles displaying multiple copies of each selected mimotope on major phage coat protein. These constructed phages elicited T cell-mediated immune response, which was predominated by the type 1 T cell response. Mimotopes alone contributed to the type 1 T cell response by promoting IL-2 production. Fel d 1 mimotopes, as well as their filamentous phage immunogenic carriers, represent promising candidates in the development of hypoallergenic vaccine against cat allergy. Copyright © 2016 Elsevier Ltd. All rights reserved.

A New Role of Fine Excipient Materials in Carrier-Based Dry Powder Inhalation Mixtures: Effect on Deagglomeration of Drug Particles During Mixing Revealed.

PubMed

Shalash, Ahmed O; Elsayed, Mustafa M A

2017-11-01

The potential of fine excipient materials to improve the performance of carrier-based dry powder inhalation mixtures is well acknowledged. The mechanisms underlying this potential are, however, open to question till date. Elaborate understanding of these mechanisms is a requisite for rational rather than empirical development of ternary dry powder inhalation mixtures. While effects of fine excipient materials on drug adhesion to and detachment from surfaces of carrier particle have been extensively investigated, effects on other processes, such as carrier-drug mixing, capsule/blister/device filling, or aerosolization in inhaler devices, have received little attention. We investigated the influence of fine excipient materials on the outcome of the carrier-drug mixing process. We studied the dispersibility of micronized fluticasone propionate particles after mixing with α-lactose monohydrate blends comprising different fine particle concentrations. Increasing the fine (D < 10.0 μm) excipient fraction from 1.84 to 8.70% v/v increased the respirable drug fraction in the excipient-drug mixture from 56.42 to 67.80% v/v (p < 0.05). The results suggest that low concentrations of fine excipient particles bind to active sites on and fill deep crevices in coarse carrier particles. As the concentration of fine excipient particles increases beyond that saturating active sites, they fill the spaces between and adhere to the surfaces of coarse carrier particles, creating projections and micropores. They thereby promote deagglomeration of drug particles during carrier-drug mixing. The findings pave the way for a comprehensive understanding of contributions of fine excipient materials to the performance of carrier-based dry powder inhalation mixtures.

Phenotype, penetrance, and treatment of 133 CTLA-4-insufficient individuals.

PubMed

Schwab, Charlotte; Gabrysch, Annemarie; Olbrich, Peter; Patiño, Virginia; Warnatz, Klaus; Wolff, Daniel; Hoshino, Akihiro; Kobayashi, Masao; Imai, Kohsuke; Takagi, Masatoshi; Dybedal, Ingunn; Haddock, Jamanda A; Sansom, David; Lucena, Jose M; Seidl, Maximilian; Schmitt-Gräff, Annette; Reiser, Veronika; Emmerich, Florian; Frede, Natalie; Bulashevska, Alla; Salzer, Ulrich; Schubert, Desirée; Hayakawa, Seiichi; Okada, Satoshi; Kanariou, Maria; Kucuk, Zeynep Yesim; Chapdelaine, Hugo; Petruzelkova, Lenka; Sumnik, Zdenek; Sediva, Anna; Slatter, Mary; Arkwright, Peter D; Cant, Andrew; Lorenz, Hanns-Martin; Giese, Thomas; Lougaris, Vassilios; Plebani, Alessandro; Price, Christina; Sullivan, Kathleen E; Moutschen, Michel; Litzman, Jiri; Freiberger, Tomas; van de Veerdonk, Frank L; Recher, Mike; Albert, Michael H; Hauck, Fabian; Seneviratne, Suranjith; Schmid, Jana Pachlopnik; Kolios, Antonios; Unglik, Gary; Klemann, Christian; Speckmann, Carsten; Ehl, Stephan; Leichtner, Alan; Blumberg, Richard; Franke, Andre; Snapper, Scott; Zeissig, Sebastian; Cunningham-Rundles, Charlotte; Giulino-Roth, Lisa; Elemento, Olivier; Dückers, Gregor; Niehues, Tim; Fronkova, Eva; Kanderová, Veronika; Platt, Craig D; Chou, Janet; Chatila, Talal; Geha, Raif; McDermott, Elizabeth; Bunn, Su; Kurzai, Monika; Schulz, Ansgar; Alsina, Laia; Casals, Ferran; Deyà-Martinez, Angela; Hambleton, Sophie; Kanegane, Hirokazu; Taskén, Kjetil; Neth, Olaf; Grimbacher, Bodo

2018-05-04

Cytotoxic-T-lymphocyte-antigen-4 (CTLA-4) is a negative immune regulator. Heterozygous CTLA4 germline mutations can cause a complex immune dysregulation syndrome in humans. To characterize the penetrance, the clinical features and the best treatment options in 133 CTLA4 mutation carriers. Genetics, clinical features, laboratory values, and outcome of treatment options were assessed in a worldwide cohort of CTLA4 mutation carriers. We identified 133 individuals from 54 unrelated families carrying 45 different heterozygous CTLA4 mutations, including 28 previously undescribed mutations. Ninety mutation carriers were considered affected, suggesting the clinical penetrance of at least 67%; median age of onset was 11 years, and mortality rate within affected mutation carriers was 16% (n=15). Main clinical manifestations included hypogammaglobulinemia (84%), lymphoproliferation (73%), autoimmune cytopenia (62%), respiratory- (68%), gastrointestinal- (59%), or neurological features (29%). Eight affected mutation carriers developed lymphoma, three gastric cancer. An EBV association was found in six malignancies. CTLA4 mutations were associated with lymphopenia and decreased T-, B-, and NK-cell counts. Successful targeted therapies included the application of CTLA-4-fusion-proteins, mTOR-inhibitors, and hematopoietic stem cell transplantation. EBV reactivation occurred in two affected mutation carriers under immunosuppression. Affected mutation carriers with CTLA-4 insufficiency may present in any medical specialty. Family members should be counseled, as disease manifestation may occur as late as age 50. EBV- and CMV-associated complications must be closely monitored. Treatment interventions should be coordinated in clinical trials. This large cohort of affected CTLA4 mutation carriers gives first insights into different possible treatment options and presents available clinical information on treatment response and survival. With this knowledge, affected mutation carriers will benefit from an individualized management. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. All rights reserved.

Population-based screening for breast and ovarian cancer risk due to BRCA1 and BRCA2

PubMed Central

Gabai-Kapara, Efrat; Lahad, Amnon; Kaufman, Bella; Friedman, Eitan; Segev, Shlomo; Renbaum, Paul; Beeri, Rachel; Gal, Moran; Grinshpun-Cohen, Julia; Djemal, Karen; Mandell, Jessica B.; Lee, Ming K.; Beller, Uziel; Catane, Raphael; King, Mary-Claire; Levy-Lahad, Ephrat

2014-01-01

In the Ashkenazi Jewish (AJ) population of Israel, 11% of breast cancer and 40% of ovarian cancer are due to three inherited founder mutations in the cancer predisposition genes BRCA1 and BRCA2. For carriers of these mutations, risk-reducing salpingo-oophorectomy significantly reduces morbidity and mortality. Population screening for these mutations among AJ women may be justifiable if accurate estimates of cancer risk for mutation carriers can be obtained. We therefore undertook to determine risks of breast and ovarian cancer for BRCA1 and BRCA2 mutation carriers ascertained irrespective of personal or family history of cancer. Families harboring mutations in BRCA1 or BRCA2 were ascertained by identifying mutation carriers among healthy AJ males recruited from health screening centers and outpatient clinics. Female relatives of the carriers were then enrolled and genotyped. Among the female relatives with BRCA1 or BRCA2 mutations, cumulative risk of developing either breast or ovarian cancer by age 60 and 80, respectively, were 0.60 (± 0.07) and 0.83 (± 0.07) for BRCA1 carriers and 0.33 (± 0.09) and 0.76 (± 0.13) for BRCA2 carriers. Risks were higher in recent vs. earlier birth cohorts (P = 0.006). High cancer risks in BRCA1 or BRCA2 mutation carriers identified through healthy males provide an evidence base for initiating a general screening program in the AJ population. General screening would identify many carriers who are not evaluated by genetic testing based on family history criteria. Such a program could serve as a model to investigate implementation and outcomes of population screening for genetic predisposition to cancer in other populations. PMID:25192939

The Relationship Between the Permeability and the Performance of Carrier-Based Dry Powder Inhalation Mixtures: New Insights and Practical Guidance.

PubMed

Shalash, Ahmed O; Khalafallah, Nawal M; Molokhia, Abdulla M; Elsayed, Mustafa M A

2018-02-01

The permeability of a powder bed reflects its particle size distribution, shape, packing, porosity, cohesivity, and tensile strength in a manner relevant to powder fluidization. The relationship between the permeability and the performance of carrier-based dry powder inhalation (DPI) mixtures has, however, aroused controversy. The current study sought to gain new insights into the relationship and to explore its potential applications. We studied eight lactose materials as DPI carriers. The carriers covered a broad permeability range of 0.42-13.53 D and moreover differed in particle size distribution, particle shape, crystal form, and/or porosity. We evaluated the performance of inhalation mixtures of each of these carriers and fluticasone propionate after aerosolization from an Aerolizer®, a model turbulent-shear inhaler, at a flow rate of 60 L/min. Starting from the high permeability side, the inhalation mixture performance increased as the carrier permeability decreased until optimum performance was reached at permeability of ~ 3.2 D. Increased resistance to air flow strengthens aerodynamic dispersion forces. The inhalation mixture performance then decreased as the carrier permeability further decreased. Very high resistance to air flow restricts powder dispersion. The permeability accounted for effects of carrier size, shape, and macroporosity on the performance. We confirmed the relationship by analysis of two literature permeability-performance datasets, representing measurements that differ from ours in terms of carrier grades, drug, technique used to determine permeability, turbulent-shear inhaler, and/or aerosolization flow rate. Permeability provides useful information that can aid development of DPI mixtures for turbulent-shear inhalers. A practical guidance is provided.

Evaluation of chromosome 6p22 as a breast cancer risk modifier locus in a follow-up study of BRCA2 mutation carriers

PubMed Central

Stevens, Kristen N.; Wang, Xianshu; Fredericksen, Zachary; Pankratz, Vernon S.; Greene, Mark H.; Andrulis, Irene L.; Thomassen, Mads; Caligo, Maria; Nathanson, Katherine L.; Jakubowska, Anna; Osorio, Ana; Hamann, Ute; Godwin, Andrew K.; Stoppa-Lyonnet, Dominique; Southey, Melissa; Buys, Saundra S.; Singer, Christian F.; Hansen, Thomas V.O.; Arason, Adalgeir; Offit, Kenneth; Piedmonte, Marion; Montagna, Marco; Imyanitov, Evgeny; Tihomirova, Laima; Sucheston, Lara; Beattie, Mary; Neuhausen, Susan L.; Szabo, Csilla I.; Simard, Jacques; Spurdle, Amanda B.; Healey, Sue; Chen, Xiaoqing; Rebbeck, Timothy R.; Easton, Douglas F.; Chenevix-Trench, Georgia; Antoniou, Antonis C; Couch, Fergus J.

2012-01-01

Several common germline variants identified through genome-wide association studies of breast cancer risk in the general population have recently been shown to be associated with breast cancer risk for BRCA1 and/or BRCA2 mutation carriers. When combined, these variants can identify marked differences in the absolute risk of developing breast cancer for mutation carriers, suggesting that additional modifier loci may further enhance individual risk assessment for BRCA1 and BRCA2 mutation carriers. Recently, a common variant on 6p22 (rs9393597) was found to be associated with increased breast cancer risk for BRCA2 mutation carriers [Hazard ratio (HR)=1.55, 95% CI 1.25–1.92, p=6.0×10−5]. This observation was based on data from GWAS studies in which, despite statistical correction for multiple comparisons, the possibility of false discovery remains a concern. Here we report on an analysis of this variant in an additional 6,165 BRCA1 and 3,900 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). In this replication analysis, rs9393597 was not associated with breast cancer risk for BRCA2 mutation carriers [HR=1.09, 95% CI 0.96–1.24, p=0.18]. No association with ovarian cancer risk for BRCA1 or BRCA2 mutation carriers or with breast cancer risk for BRCA1 mutation carriers was observed. This follow-up study suggests that, contrary to our initial report, this variant is not associated with breast cancer risk among individuals with germline BRCA2 mutations. PMID:23011509

A review of recent advances in the spherical harmonics expansion method for semiconductor device simulation.

PubMed

Rupp, K; Jungemann, C; Hong, S-M; Bina, M; Grasser, T; Jüngel, A

The Boltzmann transport equation is commonly considered to be the best semi-classical description of carrier transport in semiconductors, providing precise information about the distribution of carriers with respect to time (one dimension), location (three dimensions), and momentum (three dimensions). However, numerical solutions for the seven-dimensional carrier distribution functions are very demanding. The most common solution approach is the stochastic Monte Carlo method, because the gigabytes of memory requirements of deterministic direct solution approaches has not been available until recently. As a remedy, the higher accuracy provided by solutions of the Boltzmann transport equation is often exchanged for lower computational expense by using simpler models based on macroscopic quantities such as carrier density and mean carrier velocity. Recent developments for the deterministic spherical harmonics expansion method have reduced the computational cost for solving the Boltzmann transport equation, enabling the computation of carrier distribution functions even for spatially three-dimensional device simulations within minutes to hours. We summarize recent progress for the spherical harmonics expansion method and show that small currents, reasonable execution times, and rare events such as low-frequency noise, which are all hard or even impossible to simulate with the established Monte Carlo method, can be handled in a straight-forward manner. The applicability of the method for important practical applications is demonstrated for noise simulation, small-signal analysis, hot-carrier degradation, and avalanche breakdown.

Optimization of nanostructured lipid carriers for topical delivery of nimesulide using Box-Behnken design approach.

PubMed

Moghddam, Seyedeh Marziyeh Mahdavi; Ahad, Abdul; Aqil, Mohd; Imam, Syed Sarim; Sultana, Yasmin

2017-05-01

The aim of the present study was to develop and optimize topically applied nimesulide-loaded nanostructured lipid carriers. Box-Behnken experimental design was applied for optimization of nanostructured lipid carriers. The independent variables were ratio of stearic acid: oleic acid (X 1 ), poloxamer 188 concentration (X 2 ) and lecithin concentration (X 3 ) while particle size (Y 1 ) and entrapment efficiency (Y 2 ) were the chosen responses. Further, skin penetration study, in vitro release, confocal laser scanning microscopy and stability study were also performed. The optimized nanostructured lipid carriers of nimesulide provide reasonable particle size, flux, and entrapment efficiency. Optimized formulation (F9) with mean particle size of 214.4 ± 11 nm showed 89.4 ± 3.40% entrapment efficiency and achieved mean flux 2.66 ± 0.09 μg/cm 2 /h. In vitro release study showed prolonged drug release from the optimized formulation following Higuchi release kinetics with R 2 value of 0.984. Confocal laser scanning microscopy revealed an enhanced penetration of Rhodamine B-loaded nanostructured lipid carriers to the deeper layers of the skin. The stability study confirmed that the optimized formulation was considerably stable at refrigerator temperature as compared to room temperature. Our results concluded that nanostructured lipid carriers are an efficient carrier for topical delivery of nimesulide.

Inorganic Nanomaterials as Carriers for Drug Delivery.

PubMed

Chen, Shizhu; Hao, Xiaohong; Liang, Xingjie; Zhang, Qun; Zhang, Cuimiao; Zhou, Guoqiang; Shen, Shigang; Jia, Guang; Zhang, Jinchao

2016-01-01

For safe and effective therapy, drugs must be delivered efficiently and with minimal systemic side effects. Nanostructured drug carriers enable the delivery of small-molecule drugs as well as nucleic acids and proteins. Inorganic nanomaterials are ideal for drug delivery platforms due to their unique physicochemical properties, such as facile preparation, good storage stability and biocompatibility. Many inorganic nanostructure-based drug delivery platforms have been prepared. Although there are still many obstacles to overcome, significant advances have been made in recent years. This review focuses on the status and development of inorganic nanostructures, including silica, quantum dots, gold, carbon-based and magnetic iron oxide-based nanostructures, as carriers for chemical and biological drugs. We specifically highlight the extensive use of these inorganic drug carriers for cancer therapy. Finally, we discuss the most important areas in the field that urgently require further study.

Facilitated transport of small molecules and ions for energy-efficient membranes.

PubMed

Li, Yifan; Wang, Shaofei; He, Guangwei; Wu, Hong; Pan, Fusheng; Jiang, Zhongyi

2015-01-07

In nature, the biological membrane can selectively transport essential small molecules/ions through facilitated diffusion via carrier proteins. Intrigued by this phenomenon and principle, membrane researchers have successfully employed synthetic carriers and carrier-mediated reversible reactions to enhance the separation performance of synthetic membranes. However, the existing facilitated transport membranes as well as the relevant facilitated transport theories have scarcely been comprehensively reviewed in the literature. This tutorial review primarily covers the two aspects of facilitated transport theories: carrier-mediated transport mechanisms and facilitated transport chemistries, including the design and fabrication of facilitated transport membranes. The applications of facilitated transport membranes in energy-intensive membrane processes (gas separation, pervaporation, and proton exchange membrane fuel cells) have also been discussed. Hopefully, this review will provide guidelines for the future research and development of facilitated transport membranes with high energy efficiency.

Sensitive frequency dependence of the carrier-envelope phase effect on bound-bound transitions: An interference perspective

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

Peng Dian; Fu Panming; Wang Bingbing

2010-11-15

We investigate numerically with Hylleraas coordinates the frequency dependence of the carrier-envelope phase (CEP) effect on bound-bound transitions of helium induced by an ultrashort laser pulse of a few cycles. We find that the CEP effect is very sensitive to the carrier frequency of the laser pulse, occurring regularly even at far-off-resonance frequencies. By analyzing a two-level model, we find that the CEP effect can be attributed to the quantum interference between neighboring multiphoton transition pathways, which is made possible by the broadened spectrum of the ultrashort laser pulse. A general picture is developed along this line to understand themore » sensitivity of the CEP effect to the laser's carrier frequency. Multilevel influence on the CEP effect is also discussed.« less

Limitations of high dose carrier based formulations.

PubMed

Yeung, Stewart; Traini, Daniela; Tweedie, Alan; Lewis, David; Church, Tanya; Young, Paul M

2018-06-10

This study was performed to investigate how increasing the active pharmaceutical ingredient (API) content within a formulation affects the dispersion of particles and the aerosol performance efficiency of a carrier based dry powder inhalable (DPI) formulation, using a custom dry powder inhaler (DPI) development rig. Five formulations with varying concentrations of API beclomethasone dipropionate (BDP) between 1% and 30% (w/w) were formulated as a multi-component carrier system containing coarse lactose and fine lactose with magnesium stearate. The morphology of the formulation and each component were investigated using scanning electron micrographs while the particle size was measured by laser diffraction. The aerosol performance, in terms of aerodynamic diameter, was assessed using the British pharmacopeia Apparatus E cascade impactor (Next generation impactor). Chemical analysis of the API was observed by high performance liquid chromatography (HPLC). Increasing the concentration of BDP in the blend resulted in increasing numbers and size of individual agglomerates and densely packed BDP multi-layers on the surface of the lactose carrier. BDP present within the multi-layer did not disperse as individual primary particles but as dense agglomerates, which led to a decrease in aerosol performance and increased percentage of BDP deposition within the Apparatus E induction port and pre-separator. As the BDP concentration in the blends increases, aerosol performance of the formulation decreases, in an inversely proportional manner. Concurrently, the percentage of API deposition in the induction port and pre-separator could also be linked to the amount of micronized particles (BDP and Micronized composite carrier) present in the formulation. The effect of such dose increase on the behaviour of aerosol dispersion was investigated to gain greater insight in the development and optimisation of higher dosed carrier-based formulations. Copyright © 2018 Elsevier B.V. All rights reserved.

A nonsynonymous polymorphism in IRS1 modifies risk of developing breast and ovarian cancers in BRCA1 and ovarian cancer in BRCA2 mutation carriers.

PubMed

Ding, Yuan C; McGuffog, Lesley; Healey, Sue; Friedman, Eitan; Laitman, Yael; Paluch-Shimon, Shani-; Kaufman, Bella; Liljegren, Annelie; Lindblom, Annika; Olsson, Håkan; Kristoffersson, Ulf; Stenmark-Askmalm, Marie; Melin, Beatrice; Domchek, Susan M; Nathanson, Katherine L; Rebbeck, Timothy R; Jakubowska, Anna; Lubinski, Jan; Jaworska, Katarzyna; Durda, Katarzyna; Gronwald, Jacek; Huzarski, Tomasz; Cybulski, Cezary; Byrski, Tomasz; Osorio, Ana; Cajal, Teresa Ramóny; Stavropoulou, Alexandra V; Benítez, Javier; Hamann, Ute; Rookus, Matti; Aalfs, Cora M; de Lange, Judith L; Meijers-Heijboer, Hanne E J; Oosterwijk, Jan C; van Asperen, Christi J; Gómez García, Encarna B; Hoogerbrugge, Nicoline; Jager, Agnes; van der Luijt, Rob B; Easton, Douglas F; Peock, Susan; Frost, Debra; Ellis, Steve D; Platte, Radka; Fineberg, Elena; Evans, D Gareth; Lalloo, Fiona; Izatt, Louise; Eeles, Ros; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Cole, Trevor; Cook, Jackie; Brewer, Carole; Tischkowitz, Marc; Godwin, Andrew K; Pathak, Harsh; Stoppa-Lyonnet, Dominique; Sinilnikova, Olga M; Mazoyer, Sylvie; Barjhoux, Laure; Léoné, Mélanie; Gauthier-Villars, Marion; Caux-Moncoutier, Virginie; de Pauw, Antoine; Hardouin, Agnès; Berthet, Pascaline; Dreyfus, Hélène; Ferrer, Sandra Fert; Collonge-Rame, Marie-Agnès; Sokolowska, Johanna; Buys, Saundra; Daly, Mary; Miron, Alex; Terry, Mary Beth; Chung, Wendy; John, Esther M; Southey, Melissa; Goldgar, David; Singer, Christian F; Tea, Muy-Kheng Maria; Gschwantler-Kaulich, Daphne; Fink-Retter, Anneliese; Hansen, Thomas V O; Ejlertsen, Bent; Johannsson, Oskar T; Offit, Kenneth; Sarrel, Kara; Gaudet, Mia M; Vijai, Joseph; Robson, Mark; Piedmonte, Marion R; Andrews, Lesley; Cohn, David; DeMars, Leslie R; DiSilvestro, Paul; Rodriguez, Gustavo; Toland, Amanda Ewart; Montagna, Marco; Agata, Simona; Imyanitov, Evgeny; Isaacs, Claudine; Janavicius, Ramunas; Lazaro, Conxi; Blanco, Ignacio; Ramus, Susan J; Sucheston, Lara; Karlan, Beth Y; Gross, Jenny; Ganz, Patricia A; Beattie, Mary S; Schmutzler, Rita K; Wappenschmidt, Barbara; Meindl, Alfons; Arnold, Norbert; Niederacher, Dieter; Preisler-Adams, Sabine; Gadzicki, Dorotehea; Varon-Mateeva, Raymonda; Deissler, Helmut; Gehrig, Andrea; Sutter, Christian; Kast, Karin; Nevanlinna, Heli; Aittomäki, Kristiina; Simard, Jacques; Spurdle, Amanda B; Beesley, Jonathan; Chen, Xiaoqing; Tomlinson, Gail E; Weitzel, Jeffrey; Garber, Judy E; Olopade, Olufunmilayo I; Rubinstein, Wendy S; Tung, Nadine; Blum, Joanne L; Narod, Steven A; Brummel, Sean; Gillen, Daniel L; Lindor, Noralane; Fredericksen, Zachary; Pankratz, Vernon S; Couch, Fergus J; Radice, Paolo; Peterlongo, Paolo; Greene, Mark H; Loud, Jennifer T; Mai, Phuong L; Andrulis, Irene L; Glendon, Gord; Ozcelik, Hilmi; Gerdes, Anne-Marie; Thomassen, Mads; Jensen, Uffe Birk; Skytte, Anne-Bine; Caligo, Maria A; Lee, Andrew; Chenevix-Trench, Georgia; Antoniou, Antonis C; Neuhausen, Susan L

2012-08-01

We previously reported significant associations between genetic variants in insulin receptor substrate 1 (IRS1) and breast cancer risk in women carrying BRCA1 mutations. The objectives of this study were to investigate whether the IRS1 variants modified ovarian cancer risk and were associated with breast cancer risk in a larger cohort of BRCA1 and BRCA2 mutation carriers. IRS1 rs1801123, rs1330645, and rs1801278 were genotyped in samples from 36 centers in the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analyzed by a retrospective cohort approach modeling the associations with breast and ovarian cancer risks simultaneously. Analyses were stratified by BRCA1 and BRCA2 status and mutation class in BRCA1 carriers. Rs1801278 (Gly972Arg) was associated with ovarian cancer risk for both BRCA1 (HR, 1.43; 95% confidence interval (CI), 1.06-1.92; P = 0.019) and BRCA2 mutation carriers (HR, 2.21; 95% CI, 1.39-3.52, P = 0.0008). For BRCA1 mutation carriers, the breast cancer risk was higher in carriers with class II mutations than class I mutations (class II HR, 1.86; 95% CI, 1.28-2.70; class I HR, 0.86; 95%CI, 0.69-1.09; P(difference), 0.0006). Rs13306465 was associated with ovarian cancer risk in BRCA1 class II mutation carriers (HR, 2.42; P = 0.03). The IRS1 Gly972Arg single-nucleotide polymorphism, which affects insulin-like growth factor and insulin signaling, modifies ovarian cancer risk in BRCA1 and BRCA2 mutation carriers and breast cancer risk in BRCA1 class II mutation carriers. These findings may prove useful for risk prediction for breast and ovarian cancers in BRCA1 and BRCA2 mutation carriers. ©2012 AACR.

AURKA F31I Polymorphism and Breast Cancer Risk in BRCA1 and BRCA2 Mutation Carriers: A CIMBA study

PubMed Central

Couch, Fergus J.; Sinilnikova, Olga; Vierkant, Robert A; Pankratz, V. Shane; Fredericksen, Zachary S.; Stoppa-Lyonnet, Dominique; Coupier, Isabelle; Hughes, David; Hardouin, Agnès; Berthet, Pascaline; Peock, Susan; Cook, Margaret; Baynes, Caroline; Hodgson, Shirley; Morrison, Patrick J.; Porteous, Mary E.; Jakubowska, Anna; Lubinski, Jan; Gronwald, Jacek; Spurdle, Amanda B.; Schmutzler, Rita; Versmold, Beatrix; Engel, Christoph; Meindl, Alfons; Sutter, Christian; Horst, Jurgen; Schaefer, Dieter; Offit, Kenneth; Kirchhoff, Tomas; Andrulis, Irene L.; Ilyushik, Eduard; Glendon, Gordon; Devilee, Peter; Vreeswijk, Maaike P.G.; Vasen, Hans F.A.; Borg, Ake; Backenhorn, Katja; Struewing, Jeffery P.; Greene, Mark H.; Neuhausen, Susan L.; Rebbeck, Timothy R.; Nathanson, Katherine; Domchek, Susan; Wagner, Theresa; Garber, Judy E.; Szabo, Csilla; Zikan, Michal; Foretova, Lenka; Olson, Janet E.; Sellers, Thomas A.; Lindor, Noralane; Nevanlinna, Heli; Tommiska, Johanna; Aittomaki, Kristiina; Hamann, Ute; Rashid, Muhammad U.; Torres, Diana; Simard, Jacques; Durocher, Francine; Guenard, Frederic; Lynch, Henry T.; Isaacs, Claudine; Weitzel, Jeffrey; Olopade, Olufunmilayo I.; Narod, Steven; Daly, Mary B.; Godwin, Andrew K.; Tomlinson, Gail; Easton, Douglas F.; Chenevix-Trench, Georgia; Antoniouon, Antonis C.

2009-01-01

The AURKA oncogene is associated with abnormal chromosome segregation and aneuploidy and predisposition to cancer. Amplification of AURKA has been detected at higher frequency in tumors from BRCA1 and BRCA2 mutation carriers than in sporadic breast tumors, suggesting that overexpression of AURKA and inactivation of BRCA1 and BRCA2 co-operate during tumor development and progression. The F31I polymorphism in AURKA has been associated with breast cancer risk in the homozygous state in prior studies. We evaluated whether the AURKA F31I polymorphism modifies breast cancer risk in BRCA1 and BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). CIMBA was established to provide sufficient statistical power through increased numbers of mutation carriers to identify polymorphisms that act as modifiers of cancer risk and can refine breast cancer risk estimates in BRCA1 and BRCA2 mutation carriers. A total of 4935 BRCA1 and 2241 BRCA2 mutation carriers and 11 individuals carrying both BRCA1 and BRCA2 mutations were genotyped for F31I. Overall, homozygosity for the 31I allele was not significantly associated with breast cancer risk in BRCA1 and BRCA2 carriers combined (HR = 0.91; 95% CI 0.77-1.06). Similarly, no significant association was seen in BRCA1 (HR = 0.90; 95% CI 0.75-1.08) or BRCA2 carriers (HR = 0.93; 95% CI 0.67-1.29) or when assessing the modifying effects of either bilateral prophylactic oophorectomy or menopausal status of BRCA1 and BRCA2 carriers. In summary, the F31I polymorphism in AURKA is not associated with a modified risk of breast cancer in BRCA1 and BRCA2 carriers. PMID:17627006

A non-synonymous polymorphism in IRS1 modifies risk of developing breast and ovarian cancers in BRCA1 and ovarian cancer in BRCA2 mutation carriers

PubMed Central

Ding, Yuan C.; McGuffog, Lesley; Healey, Sue; Friedman, Eitan; Laitman, Yael; Shani-Shimon–Paluch; Kaufman, Bella; Liljegren, Annelie; Lindblom, Annika; Olsson, Håkan; Kristoffersson, Ulf; Stenmark-Askmalm, Marie; Melin, Beatrice; Domchek, Susan M.; Nathanson, Katherine L.; Rebbeck, Timothy R.; Jakubowska, Anna; Lubinski, Jan; Jaworska, Katarzyna; Durda, Katarzyna; Gronwald, Jacek; Huzarski, Tomasz; Cybulski, Cezary; Byrski, Tomasz; Osorio, Ana; Cajal, Teresa Ramóny; Stavropoulou, Alexandra V; Benítez, Javier; Hamann, Ute; Rookus, Matti; Aalfs, Cora M.; de Lange, Judith L.; Meijers-Heijboer, Hanne E.J.; Oosterwijk, Jan C.; van Asperen, Christi J.; García, Encarna B. Gómez; Hoogerbrugge, Nicoline; Jager, Agnes; van der Luijt, Rob B.; Easton, Douglas F.; Peock, Susan; Frost, Debra; Ellis, Steve D.; Platte, Radka; Fineberg, Elena; Evans, D. Gareth; Lalloo, Fiona; Izatt, Louise; Eeles, Ros; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Cole, Trevor; Cook, Jackie; Brewer, Carole; Tischkowitz, Marc; Godwin, Andrew K.; Pathak, Harsh; Stoppa-Lyonnet, Dominique; Sinilnikova, Olga M.; Mazoyer, Sylvie; Barjhoux, Laure; Léoné, Mélanie; Gauthier-Villars, Marion; Caux-Moncoutier, Virginie; de Pauw, Antoine; Hardouin, Agnès; Berthet, Pascaline; Dreyfus, Hélène; Ferrer, Sandra Fert; Collonge-Rame, Marie-Agnès; Sokolowska, Johanna; Buys, Saundra; Daly, Mary; Miron, Alex; Terry, Mary Beth; Chung, Wendy; John, Esther M; Southey, Melissa; Goldgar, David; Singer, Christian F; Maria, Muy-Kheng Tea; Gschwantler-Kaulich, Daphne; Fink-Retter, Anneliese; Hansen, Thomas v. O.; Ejlertsen, Bent; Johannsson, Oskar Th.; Offit, Kenneth; Sarrel, Kara; Gaudet, Mia M.; Vijai, Joseph; Robson, Mark; Piedmonte, Marion R; Andrews, Lesley; Cohn, David; DeMars, Leslie R.; DiSilvestro, Paul; Rodriguez, Gustavo; Toland, Amanda Ewart; Montagna, Marco; Agata, Simona; Imyanitov, Evgeny; Isaacs, Claudine; Janavicius, Ramunas; Lazaro, Conxi; Blanco, Ignacio; Ramus, Susan J; Sucheston, Lara; Karlan, Beth Y.; Gross, Jenny; Ganz, Patricia A.; Beattie, Mary S.; Schmutzler, Rita K.; Wappenschmidt, Barbara; Meindl, Alfons; Arnold, Norbert; Niederacher, Dieter; Preisler-Adams, Sabine; Gadzicki, Dorotehea; Varon-Mateeva, Raymonda; Deissler, Helmut; Gehrig, Andrea; Sutter, Christian; Kast, Karin; Nevanlinna, Heli; Aittomäki, Kristiina; Simard, Jacques; Spurdle, Amanda B.; Beesley, Jonathan; Chen, Xiaoqing; Tomlinson, Gail E.; Weitzel, Jeffrey; Garber, Judy E.; Olopade, Olufunmilayo I.; Rubinstein, Wendy S.; Tung, Nadine; Blum, Joanne L.; Narod, Steven A.; Brummel, Sean; Gillen, Daniel L.; Lindor, Noralane; Fredericksen, Zachary; Pankratz, Vernon S.; Couch, Fergus J.; Radice, Paolo; Peterlongo, Paolo; Greene, Mark H.; Loud, Jennifer T.; Mai, Phuong L.; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Gerdes, Anne-Marie; Thomassen, Mads; Jensen, Uffe Birk; Skytte, Anne-Bine; Caligo, Maria A.; Lee, Andrew; Chenevix-Trench, Georgia; Antoniou, Antonis C; Neuhausen, Susan L.

2012-01-01

Background We previously reported significant associations between genetic variants in insulin receptor substrate 1 (IRS1) and breast cancer risk in women carrying BRCA1 mutations. The objectives of this study were to investigate whether the IRS1 variants modified ovarian cancer risk and were associated with breast cancer risk in a larger cohort of BRCA1 and BRCA2 mutation carriers. Methods IRS1 rs1801123, rs1330645, and rs1801278 were genotyped in samples from 36 centers in the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analyzed by a retrospective cohort approach modeling the associations with breast and ovarian cancer risks simultaneously. Analyses were stratified by BRCA1 and BRCA2 status and mutation class in BRCA1 carriers. Results Rs1801278 (Gly972Arg) was associated with ovarian cancer risk for both BRCA1 [Hazard ratio (HR) = 1.43; 95% CI: 1.06–1.92; p = 0.019] and BRCA2 mutation carriers (HR=2.21; 95% CI: 1.39–3.52, p=0.0008). For BRCA1 mutation carriers, the breast cancer risk was higher in carriers with class 2 mutations than class 1 (mutations (class 2 HR=1.86, 95% CI: 1.28–2.70; class 1 HR=0.86, 95%CI:0.69–1.09; p-for difference=0.0006). Rs13306465 was associated with ovarian cancer risk in BRCA1 class 2 mutation carriers (HR = 2.42; p = 0.03). Conclusion The IRS1 Gly972Arg SNP, which affects insulin-like growth factor and insulin signaling, modifies ovarian cancer risk in BRCA1 and BRCA2 mutation carriers and breast cancer risk in BRCA1 class 2 mutation carriers. Impact These findings may prove useful for risk prediction for breast and ovarian cancers in BRCA1 and BRCA2 mutation carriers. PMID:22729394

A Mathematical Model for Simulating Remediation of Groundwater Contaminated by Heavy Metals using Bio-Carriers with Dead Baccilus sp. B1 and Polysulfone

NASA Astrophysics Data System (ADS)

Seo, H.; Wang, S.; Lee, M.

2010-12-01

The remediation of groundwater contaminated by heavy metals, organic contaminants, etc. using various types of bio-carriers has been widely studied as a novel technology in the literature. In this study, a series of batch experiments were conducted to investigated the fundamental characteristics in the removal process using bio-carriers (beads) with dead Bacillus sp. B1 and polysulfone. Through equilibrium and kinetic sorption experiments, sorption efficiencies for lead and copper under various conditions such as pH, temperature, contaminant concentration, etc. were examined and sorption parameters including maximum sorption capacities were obtained for model applications. Experimental data showed that equilibrium sorption patterns for Pb2+and Cu2+on bio-carrier beads follows Langmuir sorption isotherm and that the sorption dynamics can be described with a pseudo-second-order kinetics. One dimensional advective-dispersive-reactive transport model was also developed for simulating and analyzing the remediation processes. The HSDM (homogeneous surface diffusion model) were incorporated in the model to take into account the mass transfer and sorption mechanisms around/inside the bio-carrier beads. Applying the proposed model, numerical column experiments were carried out and the simulation results reasonably described temporal and spatial distribution of Pb2+and Cu2+in a fixed-bed flow-through sorption column. Experimental and numerical results showed that the main mechanism of the bio-carrier to remove heavy metals is the sorption on/inside of the bio-carriers and the bio-carriers can function as excellent biosorbents for the removal of heavy metal ions from groundwater.

Investigating the Mobility of Trilayer Graphene Nanoribbon in Nanoscale FETs

NASA Astrophysics Data System (ADS)

Rahmani, Meisam; Ghafoori Fard, Hassan; Ahmadi, Mohammad Taghi; Rahbarpour, Saeideh; Habibiyan, Hamidreza; Varmazyari, Vali; Rahmani, Komeil

2017-10-01

The aim of the present paper is to investigate the scaling behaviors of charge carrier mobility as one of the most remarkable characteristics for modeling of nanoscale field-effect transistors (FETs). Many research groups in academia and industry are contributing to the model development and experimental identification of multi-layer graphene FET-based devices. The approach in the present work is to provide an analytical model for carrier mobility of tri-layer graphene nanoribbon (TGN) FET. In order to do so, one starts by identifying the analytical modeling of TGN carrier velocity and ballistic conductance. At the end, a model of charge carrier mobility with numerical solution is analytically derived for TGN FET, in which the carrier concentration, temperature and channel length characteristics dependence are highlighted. Moreover, variation of band gap and gate voltage during the proposed device operation and its effect on carrier mobility is investigated. To evaluate the nanoscale FET performance, the carrier mobility model is also adopted to obtain the I-V characteristics of the device. In order to verify the accuracy of the proposed analytical model for TGN mobility, it is compared to the existing experimental data, and a satisfactory agreement is reported for analogous ambient conditions. Moreover, the proposed model is compared with the published data of single-layer graphene and bi-layer graphene, in which the obtained results demonstrate significant insights into the importance of charge carrier mobility impact in high-performance TGN FET. The work presented here is one step towards an applicable model for real-world nanoscale FETs.

Evaluation of Lumicyano™ cyanoacrylate fuming process for the development of latent fingermarks on plastic carrier bags by means of a pseudo operational comparative trial.

PubMed

Farrugia, Kevin J; Deacon, Paul; Fraser, Joanna

2014-03-01

There are a number of studies discussing recent developments of a one-step fluorescent cyanoacrylate process. This study is a pseudo operational trial to compare an example of a one-step fluorescent cyanoacrylate product, Lumicyano™, with the two recommended techniques for plastic carrier bags; cyanoacrylate fuming followed by basic yellow 40 (BY40) dyeing and powder suspensions. 100 plastic carrier bags were collected from the place of work and the items were treated as found without any additional fingermark deposition. The bags were split into three and after treatment with the three techniques a comparable number of fingermarks were detected by each technique (average of 300 fingermarks). The items treated with Lumicyano™ were sequentially processed with BY40 and an additional 43 new fingermarks were detected. Lumicyano™ appears to be a suitable technique for the development of fingermarks on plastic carrier bags and it can help save lab space and time as it does not require dyeing or drying procedures. Furthermore, contrary to other one-step cyanoacrylate products, existing cyanoacrylate cabinets do not require any modification for the treatment of articles with Lumicyano™. To date, there is little peer reviewed articles in the literature on trials related to Lumicyano™ and this study aims to contribute to fill this gap. © 2013.

Development of megasonic cleaning for silicon wafers

NASA Technical Reports Server (NTRS)

Mayer, A.

1980-01-01

A cleaning and drying system for processing at least 2500 three in. diameter wafers per hour was developed with a reduction in process cost. The system consists of an ammonia hydrogen peroxide bath in which both surfaces of 3/32 in. spaced, ion implanted wafers are cleaned in quartz carriers moved on a belt past two pairs of megasonic transducers. The wafers are dried in the novel room temperature, high velocity air dryer in the same carriers used for annealing. A new laser scanner was used effectively to monitor the cleaning ability on a sampling basis.

Ka-Band Transponder for Deep-Space Radio Science

NASA Technical Reports Server (NTRS)

Dennis, Matthew S.; Mysoor, Narayan R.; Folkner, William M.; Mendoza, Ricardo; Venkatesan, Jaikrishna

2008-01-01

A one-page document describes a Ka-band transponder being developed for use in deep-space radio science. The transponder receives in the Deep Space Network (DSN) uplink frequency band of 34.2 to 34.7 GHz, transmits in the 31.8- to 32.3 GHz DSN downlink band, and performs regenerative ranging on a DSN standard 4-MHz ranging tone subcarrier phase-modulated onto the uplink carrier signal. A primary consideration in this development is reduction in size, relative to other such transponders. The transponder design is all-analog, chosen to minimize not only the size but also the number of parts and the design time and, thus, the cost. The receiver features two stages of frequency down-conversion. The receiver locks onto the uplink carrier signal. The exciter signal for the transmitter is derived from the same source as that used to generate the first-stage local-oscillator signal. The ranging-tone subcarrier is down-converted along with the carrier to the second intermediate frequency, where the 4-MHz tone is demodulated from the composite signal and fed into a ranging-tone-tracking loop, which regenerates the tone. The regenerated tone is linearly phase-modulated onto the downlink carrier.

A Method for Forecasting the Commercial Air Traffic Schedule in the Future

NASA Technical Reports Server (NTRS)

Long, Dou; Lee, David; Gaier, Eric; Johnson, Jesse; Kostiuk, Peter

1999-01-01

This report presents an integrated set of models that forecasts air carriers' future operations when delays due to limited terminal-area capacity are considered. This report models the industry as a whole, avoiding unnecessary details of competition among the carriers. To develop the schedule outputs, we first present a model to forecast the unconstrained flight schedules in the future, based on the assumption of rational behavior of the carriers. Then we develop a method to modify the unconstrained schedules, accounting for effects of congestion due to limited NAS capacities. Our underlying assumption is that carriers will modify their operations to keep mean delays within certain limits. We estimate values for those limits from changes in planned block times reflected in the OAG. Our method for modifying schedules takes many means of reducing the delays into considerations, albeit some of them indirectly. The direct actions include depeaking, operating in off-hours, and reducing hub airports'operations. Indirect actions include using secondary airports, using larger aircraft, and selecting new hub airports, which, we assume, have already been modeled in the FAA's TAF. Users of our suite of models can substitute an alternative forecast for the TAF.

Development of a microwave photoconductance measurement technique for the study of carrier dynamics in highly-excited 4H-SiC

NASA Astrophysics Data System (ADS)

Subačius, L.; Jarašiūnas, K.; Ščajev, P.; Kato, M.

2015-12-01

The microwave conductance decay (MCD) technique combining an initially matched transmission line setup and picosecond optical excitation was developed and applied for the monitoring of transmitted and reflected microwave power transients in a 4H-SiC epilayer in a wide excitation range, from 2  ×  1014 to 1018 cm-3. The excitation-dependent decrease in measurement sensitivity in the power-law relations of the transients was observed at excess carrier densities above 1016 cm-3 due to the line mismatches and decrease in the internal microwave field in the illuminated sample. The calibration procedure of MCD data on excess carrier density was applied for the correction of the MCD transients and resulted in nearly identical MCD kinetics in the reflection and transmission. In a 35 μm-thick n-type 4H-SiC epilayer, the tendencies of the gradual decrease of the initial decay time with an excitation increase and the excitation-enhanced carrier recombination rate in MCD tails were analyzed numerically. These tendencies were attributed to the excitation dependent surface recombination rate and the enhanced trap-related bulk recombination, correspondingly.

Correlation between Photoluminescence and Carrier Transport and a Simple In Situ Passivation Method for High-Bandgap Hybrid Perovskites

DOE PAGES

Stoddard, Ryan J.; Eickemeyer, Felix T.; Katahara, John K.; ...

2017-06-21

High-bandgap mixed-halide hybrid perovskites have higher open-circuit voltage deficits and lower carrier diffusion lengths than their lower-bandgap counterparts. We have developed a ligand-assisted crystallization (LAC) technique that introduces additives in situ during the solvent wash and developed a new method to dynamically measure the absolute intensity steady-state photoluminescence and the mean carrier diffusion length simultaneously. The measurements reveal four distinct regimes of material changes and show that photoluminescence brightening often coincides with losses in carrier transport, such as in degradation or phase segregation. Further, the measurements enabled optimization of LAC on the 1.75 eV bandgap FA 0.83Cs 0.17Pb(I 0.66Br 0.34)more » 3, resulting in an enhancement of the photoluminescence quantum yield (PLQY) of over an order of magnitude, an increase of 80 meV in the quasi-Fermi level splitting (to 1.29 eV), an increase in diffusion length by a factor of 3.5 (to over 1 μm), and enhanced open-circuit voltage and short-circuit current from photovoltaics fabricated from the LAC-treated films.« less

Correlation between Photoluminescence and Carrier Transport and a Simple In Situ Passivation Method for High-Bandgap Hybrid Perovskites.

PubMed

Stoddard, Ryan J; Eickemeyer, Felix T; Katahara, John K; Hillhouse, Hugh W

2017-07-20

High-bandgap mixed-halide hybrid perovskites have higher open-circuit voltage deficits and lower carrier diffusion lengths than their lower-bandgap counterparts. We have developed a ligand-assisted crystallization (LAC) technique that introduces additives in situ during the solvent wash and developed a new method to dynamically measure the absolute intensity steady-state photoluminescence and the mean carrier diffusion length simultaneously. The measurements reveal four distinct regimes of material changes and show that photoluminescence brightening often coincides with losses in carrier transport, such as in degradation or phase segregation. Further, the measurements enabled optimization of LAC on the 1.75 eV bandgap FA 0.83 Cs 0.17 Pb(I 0.66 Br 0.34 ) 3 , resulting in an enhancement of the photoluminescence quantum yield (PLQY) of over an order of magnitude, an increase of 80 meV in the quasi-Fermi level splitting (to 1.29 eV), an increase in diffusion length by a factor of 3.5 (to over 1 μm), and enhanced open-circuit voltage and short-circuit current from photovoltaics fabricated from the LAC-treated films.

Porous Carriers for Controlled/Modulated Drug Delivery

PubMed Central

Ahuja, G.; Pathak, K.

2009-01-01

Considerable research efforts have been directed in recent years towards the development of porous carriers as controlled drug delivery matrices because of possessing several features such as stable uniform porous structure, high surface area, tunable pore size and well-defined surface properties. Owing to wide range of useful properties porous carriers have been used in pharmaceuticals for many purposes including development of floating drug delivery systems, sustained drug delivery systems. Various types of pores like open, closed, transport and blind pores in the porous solid allow them to adsorb drugs and release them in a more reproducible and predictable manner. Pharmaceutically exploited porous adsorbents includes, silica (mesoporous), ethylene vinyl acetate (macroporous), polypropylene foam powder (microporous), titanium dioxide (nanoporous). When porous polymeric drug delivery system is placed in contact with appropriate dissolution medium, release of drug to medium must be preceded by the drug dissolution in the water filled pores or from surface and by diffusion through the water filled channels. The porous carriers are used to improve the oral bioavailability of poorly water soluble drugs, to increase the dissolution of relatively insoluble powders and conversion of crystalline state to amorphous state. PMID:20376211

Estimation of free carrier concentrations in high-quality heavily doped GaN:Si micro-rods by photoluminescence and Raman spectroscopy

NASA Astrophysics Data System (ADS)

Mohajerani, M. S.; Khachadorian, S.; Nenstiel, C.; Schimpke, T.; Avramescu, A.; Strassburg, M.; Hoffmann, A.; Waag, A.

2016-03-01

The controlled growth of highly n-doped GaN micro rods is one of the major challenges in the fabrication of recently developed three-dimensional (3D) core-shell light emitting diodes (LEDs). In such structures with a large active area, higher electrical conductivity is needed to achieve higher current density. In this contribution, we introduce high quality heavily-doped GaN:Si micro-rods which are key elements of the newly developed 3D core-shell LEDs. These structures were grown by metal-organic vapor phase epitaxy (MOVPE) using selective area growth (SAG). We employed spatially resolved micro-Raman and micro-photoluminescence (PL) in order to directly determine a free-carrier concentration profile in individual GaN micro-rods. By Raman spectroscopy, we analyze the low-frequency branch of the longitudinal optical (LO)-phonon-plasmon coupled modes and estimate free carrier concentrations from ≍ 2.4 × 1019 cm-3 up to ≍ 1.5 × 1020 cm-3. Furthermore, free carrier concentrations are determined by estimating Fermi energy level from the near band edge emission measured by low-temperature PL. The results from both methods reveal a good consistency.

Commerce lab: Mission analysis and payload integration study

NASA Technical Reports Server (NTRS)

1984-01-01

Conceived as one or more arrays of carriers which would fly aboard space shuttle, Commerce Lab can provide a point of focus for implementing a series of shuttle flights, co-sponsored by NASA and U.S. domestic concerns, for performing materials processing in research and pre-commercial investigations. As an orbiting facility for testing, developing, and implementing hardware and procedures, Commerce Lab can enhance space station development and hasten space platform production capability. Tasks considered include: (1) synthesis of user requirements and identification of common element and voids; (2) definition of performance and infrastructure requirement and alternative approaches; and (3) carrier, mission model, and infrastructure development.

Supramolecular Drug Delivery Systems Based on Water-Soluble Pillar[n]arenes.

PubMed

Wu, Xuan; Gao, Lei; Hu, Xiao-Yu; Wang, Leyong

2016-06-01

Supramolecular drug delivery systems (SDDSs), including various kinds of nanostructures that are assembled by reversible noncovalent interactions, have attracted considerable attention as ideal drug carriers owing to their fascinating ability to undergo dynamic switching of structure, morphology, and function in response to various external stimuli, which provides a flexible and robust platform for designing and developing functional and smart supramolecular nano-drug carriers. Pillar[n]arenes represent a new generation of macrocyclic hosts, which have unique structures and excellent properties in host-guest chemistry. This account describes recent progress in our group to develop pillararene-based stimuli-responsive supramolecular nanostructures constructed by reversible host-guest interactions for controllable anticancer drug delivery. The potential applications of these supramolecular drug carriers in cancer treatment and the fundamental questions facing SDDSs are also discussed. © 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Identification of dominant scattering mechanism in epitaxial graphene on SiC

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

Lin, Jingjing; Guo, Liwei, E-mail: lwguo@iphy.ac.cn, E-mail: chenx29@aphy.iphy.ac.cn; Jia, Yuping

2014-05-05

A scheme of identification of scattering mechanisms in epitaxial graphene (EG) on SiC substrate is developed and applied to three EG samples grown on SiC (0001), (112{sup ¯}0), and (101{sup ¯}0) substrates. Hall measurements combined with defect detection technique enable us to evaluate the individual contributions to the carrier scatterings by defects and by substrates. It is found that the dominant scatterings can be due to either substrate or defects, dependent on the substrate orientations. The EG on SiC (112{sup ¯}0) exhibits a better control over the two major scattering mechanisms and achieves the highest mobility even with a highmore » carrier concentration, promising for high performance graphene-based electronic devices. The method developed here will shed light on major aspects in governing carrier transport in EG to harness it effectively.« less

Defect Chemistry and Plasmon Physics of Colloidal Metal Oxide Nanocrystals.

PubMed

Lounis, Sebastien D; Runnerstrom, Evan L; Llordés, Anna; Milliron, Delia J

2014-05-01

Plasmonic nanocrystals of highly doped metal oxides have seen rapid development in the past decade and represent a class of materials with unique optoelectronic properties. In this Perspective, we discuss doping mechanisms in metal oxides and the accompanying physics of free carrier scattering, both of which have implications in determining the properties of localized surface plasmon resonances (LSPRs) in these nanocrystals. The balance between activation and compensation of dopants limits the free carrier concentration of the most common metal oxides, placing a ceiling on the LSPR frequency. Furthermore, because of ionized impurity scattering of the oscillating plasma by dopant ions, scattering must be treated in a fundamentally different way in semiconductor metal oxide materials when compared with conventional metals. Though these effects are well-understood in bulk metal oxides, further study is needed to understand their manifestation in nanocrystals and corresponding impact on plasmonic properties, and to develop materials that surpass current limitations in free carrier concentration.

Mesostructured silica and aluminosilicate carriers for oxytetracycline delivery systems.

PubMed

Berger, D; Nastase, S; Mitran, R A; Petrescu, M; Vasile, E; Matei, C; Negreanu-Pirjol, T

2016-08-30

Oxytetracycline delivery systems containing various MCM-type silica and aluminosilicate with different antibiotic content were developed in order to establish the influence of the support structural and textural properties and aluminum content on the drug release profile. The antibiotic molecules were loaded into the support mesochannels by incipient wetness impregnation method using a drug concentrated aqueous solution. The carriers and drug-loaded materials were investigated by small- and wide-angle XRD, FTIR spectroscopy, TEM and N2 adsorption-desorption isotherms. Faster release kinetics of oxytetracycline from uncalcined silica and aluminosilicate supports was observed, whereas higher drug content led to lower delivery rate. The presence of aluminum into the silica network also slowed down the release rate. The antimicrobial assays performed on Staphylococcus aureus clinical isolates showed that the oxytetracycline-loaded materials containing MCM-41-type mesoporous silica or aluminosilicate carriers inhibited the bacterial development. Copyright © 2016 Elsevier B.V. All rights reserved.

Investigation of Redox Metal Oxides for Carbonaceous Fuel Conversion and CO2 Capture

NASA Astrophysics Data System (ADS)

Galinsky, Nathan Lee

The chemical looping combustion (CLC) process uses metal oxides, also referred to as oxygen carriers, in a redox scheme for conversion of carbonaceous fuels into a concentrated stream of CO2 and steam while also producing heat and electricity. The unique redox scheme of CLC allows CO2 capture with minimal energy penalty. The CLC process performance greatly depends on the oxygen carrier that is chosen. To date, more than 1000 oxygen carriers have been developed for chemical-looping processes using metal oxides containing first-row transition metals. Oxygen carriers are typically mixed with an inert ceramic support to improve their overall mechanical stability and recyclability. This study focuses on design of (i) iron oxide oxygen carriers for conversion of gaseous carbonaceous fuels and (ii) development of perovskite CaMnO 3-d with improved stability and redox properties for conversion of solid fuels. Iron oxide is cheap and environmentally benign. However, it suffers from low activity with carbonaceous fuels due partially to the low ionic conductivity of iron oxides. In order to address the low activity of iron-oxide-based oxygen carriers, support addition has been shown to lower the energy barrier of oxygen anion transport within the oxygen carrier. This work adds a mixed-ionic-and-electronic-conductor (MIEC) support to iron oxide to help facilitate O2- transport inside the lattice of iron oxide. The MIEC-supported iron oxide is compared to commonly used supports including TiO2 and Al2O 3 and the pure ionic conductor support yttria-stabilized zirconia (YSZ) for conversion of different carbonaceous fuels and hydrogen. Results show that the MIEC-supported iron oxide exhibits up to 70 times higher activity than non-MIEC-supported iron oxides for methane conversion. The MIEC supported iron oxide also shows good recyclability with only minor agglomeration and carbon formation observed. The effect of support-iron oxide synergies is further investigated to understand other physical and chemical properties that lead to highly active and recyclable oxygen carriers. Perovskite and fluorite-structured MIEC supports are tested for conversion of methane. The perovskite supported iron oxides exhibit higher activity and stability resulting from the high mixed conductivity of the support. Fluorite-structured CeO2 oxygen carriers deactivated by 75% after 10 redox cycles. This deactivation was attributed to agglomeration of iron oxide. The agglomeration was determined to occur due to Fe x+ transport during the oxidation step leading to high content of Fe on the surface of the oxygen carrier. Besides the MIEC supports, inert MgAl2O4 supported iron oxide is observed to activate in methane. The activation is attributed to carbon formation causing physical degradation of the oxygen carrier and leading to higher surface area and porosity. To achieve high activity with solid fuels, chemical looping with oxygen uncoupling (CLOU) is commonly used. This process uses oxygen carriers with high PO2 that allows the oxygen carrier to release a portion of their lattice oxygen as gaseous oxygen. In turn, the gaseous oxygen can react with solid fuel particles at a higher rate than the lattice oxygen. CaMnO 3 perovskite oxygen carriers offer high potential for CLOU. However, pure CaMnO3 suffers from long-term recyclability and sulfur poisoning. Addition of A-site (Ba and Sr) and B-site (Fe, Ni, Co, Al, and V) dopants are used to improve the performance of the base CaMnO3 oxygen carrier. Sr (A-site) and Fe (B-site) exhibit high compatibility with the base perovskite structure. Both dopants observe oxygen uncoupling properties up to 200°C below that of pure CaMnO3. Additionally, the doped structures also exhibit higher stability at high temperatures (>1000°C) and during redox cycles. The doped oxygen carriers also demonstrate significantly improved activity for coal char conversion.

Beijing’s Starter Carrier and Future Steps: Alternatives and Implications

DTIC Science & Technology

2012-01-01

Aircraft Carrier,” pp. 52–60. 49. “著名军事专家尹卓少将谈航空母舰与现 代 战 争 ” [Renowned Military Expert Rear Admiral Yin Zhuo Comments on Aircraft Carriers and Modern...play an important role in maintain- ing world peace and promoting common development.”13 Hu has since endorsed a PLAN “Far Seas” operations (远海作 战 ...1 (Winter 2011), pp. 59–78. 62. The authors thank Nan Li for these points. 63. Zhang Yuliang et al., 战 役学 [Science of Campaigns] (Beijing: National

Probability density of tunneled carrier states near heterojunctions calculated numerically by the scattering method.

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

Wampler, William R.; Myers, Samuel M.; Modine, Normand A.

2017-09-01

The energy-dependent probability density of tunneled carrier states for arbitrarily specified longitudinal potential-energy profiles in planar bipolar devices is numerically computed using the scattering method. Results agree accurately with a previous treatment based on solution of the localized eigenvalue problem, where computation times are much greater. These developments enable quantitative treatment of tunneling-assisted recombination in irradiated heterojunction bipolar transistors, where band offsets may enhance the tunneling effect by orders of magnitude. The calculations also reveal the density of non-tunneled carrier states in spatially varying potentials, and thereby test the common approximation of uniform- bulk values for such densities.

A model for sequential decoding overflow due to a noisy carrier reference. [communication performance prediction

NASA Technical Reports Server (NTRS)

Layland, J. W.

1974-01-01

An approximate analysis of the effect of a noisy carrier reference on the performance of sequential decoding is presented. The analysis uses previously developed techniques for evaluating noisy reference performance for medium-rate uncoded communications adapted to sequential decoding for data rates of 8 to 2048 bits/s. In estimating the ten to the minus fourth power deletion probability thresholds for Helios, the model agrees with experimental data to within the experimental tolerances. The computational problem involved in sequential decoding, carrier loop effects, the main characteristics of the medium-rate model, modeled decoding performance, and perspectives on future work are discussed.

Momentum and Kinetic Energy Before the Tackle in Rugby Union

PubMed Central

Hendricks, Sharief; Karpul, David; Lambert, Mike

2014-01-01

Understanding the physical demands of a tackle in match situations is important for safe and effective training, developing equipment and research. Physical components such as momentum and kinetic energy, and it relationship to tackle outcome is not known. The aim of this study was to compare momenta between ball-carrier and tackler, level of play (elite, university and junior) and position (forwards vs. backs), and describe the relationship between ball-carrier and tackler mass, velocity and momentum and the tackle outcome. Also, report on the ball-carrier and tackler kinetic energy before contact and the estimated magnitude of impact (energy distributed between ball-carrier and tackler upon contact). Velocity over 0.5 seconds before contact was determined using a 2-dimensional scaled version of the field generated from a computer alogorithm. Body masses of players were obtained from their player profiles. Momentum and kinetic energy were subsequently calculated for 60 tackle events. Ball-carriers were heavier than the tacklers (ball-carrier 100 ± 14 kg vs. tackler 93 ± 11 kg, d = 0.52, p = 0.0041, n = 60). Ball-carriers as forwards had a significantly higher momentum than backs (forwards 563 ± 226 Kg.m.s-1 n = 31 vs. backs 438 ± 135 Kg.m.s-1, d = 0.63, p = 0.0012, n = 29). Tacklers dominated 57% of tackles and ball-carriers dominated 43% of tackles. Despite the ball-carrier having a mass advantage before contact more frequently than the tackler, momentum advantage and tackle dominance between the ball-carrier and tackler was proportionally similar. These findings may reflect a characteristic of the modern game of rugby where efficiently heavier players (particularly forwards) are tactically predetermined to carry the ball in contact. Key Points First study to quantify momentum, kinetic energy, and magnitude of impact in rugby tackles across different levels in matches without a device attached to a player. Physical components alone, of either ball-carrier or tackler, are not good predictors of tackle dominance. The range of magnitudes of impact of injury free tackles observed in this study provides evidence for the physical tolerance of players during the tackle. PMID:25177182

Momentum and kinetic energy before the tackle in rugby union.

PubMed

Hendricks, Sharief; Karpul, David; Lambert, Mike

2014-09-01

Understanding the physical demands of a tackle in match situations is important for safe and effective training, developing equipment and research. Physical components such as momentum and kinetic energy, and it relationship to tackle outcome is not known. The aim of this study was to compare momenta between ball-carrier and tackler, level of play (elite, university and junior) and position (forwards vs. backs), and describe the relationship between ball-carrier and tackler mass, velocity and momentum and the tackle outcome. Also, report on the ball-carrier and tackler kinetic energy before contact and the estimated magnitude of impact (energy distributed between ball-carrier and tackler upon contact). Velocity over 0.5 seconds before contact was determined using a 2-dimensional scaled version of the field generated from a computer alogorithm. Body masses of players were obtained from their player profiles. Momentum and kinetic energy were subsequently calculated for 60 tackle events. Ball-carriers were heavier than the tacklers (ball-carrier 100 ± 14 kg vs. tackler 93 ± 11 kg, d = 0.52, p = 0.0041, n = 60). Ball-carriers as forwards had a significantly higher momentum than backs (forwards 563 ± 226 Kg(.)m(.)s(-1) n = 31 vs. backs 438 ± 135 Kg(.)m(.)s(-1), d = 0.63, p = 0.0012, n = 29). Tacklers dominated 57% of tackles and ball-carriers dominated 43% of tackles. Despite the ball-carrier having a mass advantage before contact more frequently than the tackler, momentum advantage and tackle dominance between the ball-carrier and tackler was proportionally similar. These findings may reflect a characteristic of the modern game of rugby where efficiently heavier players (particularly forwards) are tactically predetermined to carry the ball in contact. Key PointsFirst study to quantify momentum, kinetic energy, and magnitude of impact in rugby tackles across different levels in matches without a device attached to a player.Physical components alone, of either ball-carrier or tackler, are not good predictors of tackle dominance.The range of magnitudes of impact of injury free tackles observed in this study provides evidence for the physical tolerance of players during the tackle.

Ovulation rate, antral follicle count, and circulating anti-Müllerian hormone in Trio allele carriers, a novel high fecundity bovine genotype.

PubMed

García-Guerra, Alvaro; Motta, Jéssica C L; Melo, Leonardo F; Kirkpatrick, Brian W; Wiltbank, Milo C

2017-10-01

High fecundity genotypes in sheep are a valuable model to study the physiological mechanisms underlying follicle selection and the control of ovulation rate. Similar genotypes in cattle had not been described until the recent identification of a major bovine allele, termed Trio, which had a large effect on ovulation rate. The present study was designed to evaluate ovulation rate, antral follicle count (AFC), circulating ant-müllerian hormone (AMH), and the association among these measures in unstimulated and superstimulated Trio carrier cattle. We hypothesized that AFC and AMH would be variable among individual cows but would be similar between Trio carriers and non-carrier control cows and that there would be no association between these measures of follicle numbers and ovulation rate. In experiment 1, ovulation rate was determined during 4 consecutive estrous cycles in Trio carriers (n = 34) and non-carrier controls (n = 27). Ovulation rate, on average, was greater (P < 0.01) in Trio carriers (3.5 ± 0.2) compared to non-carrier controls (1.1 ± 0.1) with ∼70% of carrier cycles (n = 136) having 3-4 ovulations while only ∼5% had single ovulations. In contrast, non-carrier cycles (n = 108) were mostly single ovulation (89%) with none having more than two ovulations. In experiment 2, AFC, determined at wave emergence, was not different (P = 0.54) between Trio carriers (24.5 ± 1.3; n = 45) and non-carrier controls (23.1 ± 0.9; n = 37), and no correlation was found between AFC and mean ovulation rate in either genotype (r = -0.009 and r = -0.07; P > 0.70, respectively). In Experiment 3, circulating AMH was also not different between genotypes (P = 0.65) while correlations were found between AFC and AMH in Trio carriers (r = 0.43; P = 0.05; n = 27) and non-carrier controls (r = 0.78; P < 0.01; n = 19). In experiment 4, AFC and AMH were determined in Trio-carriers (n = 9) in relation to a synchronized follicular wave which was unstimulated or stimulated with exogenous FSH. Stimulation with FSH increased ovulation rate, compared to unstimulated Trio carriers, however no association was found between AFC or AMH and ovulation rate regardless of whether superstimulation with exogenous FSH was used. In conclusion, the novel high fecundity bovine genotype Trio, results in consistent multiple ovulations despite having similar AFC and AMH. Therefore, our results suggest that differences in antral follicle numbers during the final stages of follicle development are not a key component of the mechanism underlying multiple ovulations in Trio carriers. Copyright © 2017. Published by Elsevier Inc.

A New Carbon Nanotube-Based Breast Cancer Drug Delivery System: Preparation and In Vitro Analysis Using Paclitaxel.

PubMed

Shao, Wei; Paul, Arghya; Rodes, Laetitia; Prakash, Satya

2015-04-01

Paclitaxel (PTX) is one of the most important drugs for breast cancer; however, the drug effects are limited by its systematic toxicity and poor water solubility. Nanoparticles have been applied for delivery of cancer drugs to overcome their limitations. Toward this goal, a novel single-walled carbon nanotube (SWNT)-based drug delivery system was developed by conjugation of human serum albumin (HSA) nanoparticles for loading of antitumor agent PTX. The nanosized macromolecular SWNT-drug carrier (SWNT-HSA) was characterized by TEM, UV-Vis-NIR spectrometry, and TGA. The SWNT-based drug carrier displayed high intracellular delivery efficiency (cell uptake rate of 80%) in breast cancer MCF-7 cells, as examined by fluorescence-labeled drug carriers, suggesting the needle-shaped SWNT-HSA drug carrier was able to transport drugs across cell membrane despite its macromolecular structure. The drug loading on SWNT-based drug carrier was through high binding affinity of PTX to HSA proteins. The PTX formulated with SWNT-HSA showed greater growth inhibition activity in MCF-7 breast cancer cells than PTX formulated with HSA nanoparticle only (cell viability of 63 vs 70% in 48 h and 53 vs 62% in 72 h). The increased drug efficacy could be driven by SWNT-mediated cell internalization. These data suggest that the developed SWNT-based antitumor agent is functional and effective. However, more studies for in vivo drug delivery efficacy and other properties are needed before this delivery system can be fully realized.

ISS qualified thermal carrier equipment

NASA Astrophysics Data System (ADS)

Deuser, Mark S.; Vellinger, John C.; Jennings, Wm. M.

2000-01-01

Biotechnology is undergoing a period of rapid and sustained growth, a trend which is expected to continue as the general population ages and as new medical treatments and products are conceived. As pharmaceutical and biomedical companies continue to search for improved methods of production and, for answers to basic research questions, they will seek out new avenues of research. Space processing on the International Space Station (ISS) offers such an opportunity! Space is rapidly becoming an industrial laboratory for biotechnology research and processing. Space bioprocessing offers exciting possibilities for developing new pharmaceuticals and medical treatments, which can be used to benefit mankind on Earth. It also represents a new economic frontier for the private sector. For over eight years, the thermal carrier development team at SHOT has been working with government and commercial sector scientists who are conducting microgravity experiments that require thermal control. SHOT realized several years ago that the hardware currently being used for microgravity thermal control was becoming obsolete. It is likely that the government, academic, and industrial bioscience community members could utilize SHOT's hardware as a replacement to their current microgravity thermal carrier equipment. Moreover, SHOT is aware of several international scientists interested in utilizing our space qualified thermal carrier. SHOT's economic financing concept could be extremely beneficial to the international participant, while providing a source of geographic return for their particular region. Beginning in 2000, flight qualified thermal carriers are expected to be available to both the private and government sectors. .

Direct observation of the carrier transport process in InGaN quantum wells with a pn-junction

NASA Astrophysics Data System (ADS)

Wu, Haiyan; Ma, Ziguang; Jiang, Yang; Wang, Lu; Yang, Haojun; Li, Yangfeng; Zuo, Peng; Jia, Haiqiang; Wang, Wenxin; Zhou, Junming; Liu, Wuming; Chen, Hong

2016-11-01

A new mechanism of light-to-electricity conversion that uses InGaN/GaN QWs with a p-n junction is reported. According to the well established light-to-electricity conversion theory, quantum wells (QWs) cannot be used in solar cells and photodetectors because the photogenerated carriers in QWs usually relax to ground energy levels, owing to quantum confinement, and cannot form a photocurrent. We observe directly that more than 95% of the photoexcited carriers escape from InGaN/GaN QWs to generate a photocurrent, indicating that the thermionic emission and tunneling processes proposed previously cannot explain carriers escaping from QWs. We show that photoexcited carriers can escape directly from the QWs when the device is under working conditions. Our finding challenges the current theory and demonstrates a new prospect for developing highly efficient solar cells and photodetectors. Project supported by the National Natural Science Foundation of China (Grant Nos. 11574362, 61210014, and 11374340) and the Innovative Clean-energy Research and Application Program of Beijing Municipal Science and Technology Commission, China (Grant No. Z151100003515001).

Dual responsive PNIPAM-chitosan targeted magnetic nanopolymers for targeted drug delivery

NASA Astrophysics Data System (ADS)

Yadavalli, Tejabhiram; Ramasamy, Shivaraman; Chandrasekaran, Gopalakrishnan; Michael, Isaac; Therese, Helen Annal; Chennakesavulu, Ramasamy

2015-04-01

A dual stimuli sensitive magnetic hyperthermia based drug delivery system has been developed for targeted cancer treatment. Thermosensitive amine terminated poly-N-isopropylacrylamide complexed with pH sensitive chitosan nanoparticles was prepared as the drug carrier. Folic acid and fluorescein were tagged to the nanopolymer complex via N-hydroxysuccinimide and ethyl-3-(3-dimethylaminopropyl)carbodiimide reaction to form a fluorescent and cancer targeting magnetic carrier system. The formation of the polymer complex was confirmed using infrared spectroscopy. Gadolinium doped nickel ferrite nanoparticles prepared by a hydrothermal method were encapsulated in the polymer complex to form a magnetic drug carrier system. The proton relaxation studies on the magnetic carrier system revealed a 200% increase in the T1 proton relaxation rate. These magnetic carriers were loaded with curcumin using solvent evaporation method with a drug loading efficiency of 86%. Drug loaded nanoparticles were tested for their targeting and anticancer properties on four cancer cell lines with the help of MTT assay. The results indicated apoptosis of cancer cell lines within 3 h of incubation.

A Comparison of Photocatalytic Activities of Gold Nanoparticles Following Plasmonic and Interband Excitation and a Strategy for Harnessing Interband Hot Carriers for Solution Phase Photocatalysis

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

Zhao, Jie; Nguyen, Son C.; Ye, Rong

Light driven excitation of gold nanoparticles (GNPs) has emerged as a potential strategy to generate hot carriers for photocatalysis through excitation of localized surface plasmon resonance (LSPR). In contrast, carrier generation through excitation of interband transitions remains a less explored and underestimated pathway for photocatalytic activity. Photoinduced oxidative etching of GNPs with FeCl3 was investigated as a model reaction in order to elucidate the effects of both types of transitions. Our quantitative results show that interband transitions more efficiently generate hot carriers and that those carriers exhibit higher reactivity as compared to those generated solely by LSPR. Furthermore, by leveragingmore » the strong π-acidic character of the resulting photogenerated Au+ hole, an interband transition induced cyclization reaction of alkynylphenols was developed. One thing of note is that the, alkyne coordination to the Au+ hole intercepts the classic oxidation event and leads to the formation of the catalytically active gold clusters on subnanometer scale.« less

A Comparison of Photocatalytic Activities of Gold Nanoparticles Following Plasmonic and Interband Excitation and a Strategy for Harnessing Interband Hot Carriers for Solution Phase Photocatalysis

DOE PAGES

Zhao, Jie; Nguyen, Son C.; Ye, Rong; ...

2017-05-10

Light driven excitation of gold nanoparticles (GNPs) has emerged as a potential strategy to generate hot carriers for photocatalysis through excitation of localized surface plasmon resonance (LSPR). In contrast, carrier generation through excitation of interband transitions remains a less explored and underestimated pathway for photocatalytic activity. Photoinduced oxidative etching of GNPs with FeCl3 was investigated as a model reaction in order to elucidate the effects of both types of transitions. Our quantitative results show that interband transitions more efficiently generate hot carriers and that those carriers exhibit higher reactivity as compared to those generated solely by LSPR. Furthermore, by leveragingmore » the strong π-acidic character of the resulting photogenerated Au+ hole, an interband transition induced cyclization reaction of alkynylphenols was developed. One thing of note is that the, alkyne coordination to the Au+ hole intercepts the classic oxidation event and leads to the formation of the catalytically active gold clusters on subnanometer scale.« less

Polymeric micelles with stimuli-triggering systems for advanced cancer drug targeting.

PubMed

Nakayama, Masamichi; Akimoto, Jun; Okano, Teruo

2014-08-01

Since the 1990s, nanoscale drug carriers have played a pivotal role in cancer chemotherapy, acting through passive drug delivery mechanisms and subsequent pharmaceutical action at tumor tissues with reduction of adverse effects. Polymeric micelles, as supramolecular assemblies of amphiphilic polymers, have been considerably developed as promising drug carrier candidates, and a number of clinical studies of anticancer drug-loaded polymeric micelle carriers for cancer chemotherapy applications are now in progress. However, these systems still face several issues; at present, the simultaneous control of target-selective delivery and release of incorporated drugs remains difficult. To resolve these points, the introduction of stimuli-responsive mechanisms to drug carrier systems is believed to be a promising approach to provide better solutions for future tumor drug targeting strategies. As possible trigger signals, biological acidic pH, light, heating/cooling and ultrasound actively play significant roles in signal-triggering drug release and carrier interaction with target cells. This review article summarizes several molecular designs for stimuli-responsive polymeric micelles in response to variation of pH, light and temperature and discusses their potentials as next-generation tumor drug targeting systems.

Ultrafast momentum imaging of pseudospin-flip excitations in graphene

NASA Astrophysics Data System (ADS)

Aeschlimann, S.; Krause, R.; Chávez-Cervantes, M.; Bromberger, H.; Jago, R.; Malić, E.; Al-Temimy, A.; Coletti, C.; Cavalleri, A.; Gierz, I.

2017-07-01

The pseudospin of Dirac electrons in graphene manifests itself in a peculiar momentum anisotropy for photoexcited electron-hole pairs. These interband excitations are in fact forbidden along the direction of the light polarization and are maximum perpendicular to it. Here, we use time- and angle-resolved photoemission spectroscopy to investigate the resulting unconventional hot carrier dynamics, sampling carrier distributions as a function of energy, and in-plane momentum. We first show that the rapidly-established quasithermal electron distribution initially exhibits an azimuth-dependent temperature, consistent with relaxation through collinear electron-electron scattering. Azimuthal thermalization is found to occur only at longer time delays, at a rate that depends on the substrate and the static doping level. Further, we observe pronounced differences in the electron and hole dynamics in n -doped samples. By simulating the Coulomb- and phonon-mediated carrier dynamics we are able to disentangle the influence of excitation fluence, screening, and doping, and develop a microscopic picture of the carrier dynamics in photoexcited graphene. Our results clarify new aspects of hot carrier dynamics that are unique to Dirac materials, with relevance for photocontrol experiments and optoelectronic device applications.

Candidate genetic modifiers for breast and ovarian cancer risk in BRCA1 and BRCA2 mutation carriers

PubMed Central

Peterlongo, Paolo; Chang-Claude, Jenny; Moysich, Kirsten B.; Rudolph, Anja; Schmutzler, Rita K.; Simard, Jacques; Soucy, Penny; Eeles, Rosalind A.; Easton, Douglas F.; Hamann, Ute; Wilkening, Stefan; Chen, Bowang; Rookus, Matti A.; Schmidt, Marjanka K; van der Baan, Frederieke H.; Spurdle, Amanda B.; Walker, Logan C.; Lose, Felicity; Maia, Ana-Teresa; Montagna, Marco; Matricardi, Laura; Lubinski, Jan; Jakubowska, Anna; Gómez Garcia, Encarna B.; Olopade, Olufunmilayo I.; Nussbaum, Robert L.; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy R.; Arun, Banu K.; Karlan, Beth Y.; Orsulic, Sandra; Lester, Jenny; Chung, Wendy K.; Miron, Alex; Southey, Melissa C.; Goldgar, David E.; Buys, Saundra S.; Janavicius, Ramunas; Dorfling, Cecilia M.; van Rensburg, Elizabeth J.; Ding, Yuan Chun; Neuhausen, Susan L.; Hansen, Thomas V. O.; Gerdes, Anne-Marie; Ejlertsen, Bent; Jønson, Lars; Osorio, Ana; Martínez-Bouzas, Cristina; Benitez, Javier; Conway, Edye E.; Blazer, Kathleen R.; Weitzel, Jeffrey N.; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Scuvera, Giulietta; Barile, Monica; Ficarazzi, Filomena; Mariette, Frederique; Fortuzzi, Stefano; Viel, Alessandra; Giannini, Giuseppe; Papi, Laura; Martayan, Aline; Tibiletti, Maria Grazia; Radice, Paolo; Vratimos, Athanassios; Fostira, Florentia; Garber, Judy E.; Donaldson, Alan; Brewer, Carole; Foo, Claire; Evans, D. Gareth R.; Frost, Debra; Eccles, Diana; Brady, Angela; Cook, Jackie; Tischkowitz, Marc; Adlard, Julian; Barwell, Julian; Walker, Lisa; Izatt, Louise; Side, Lucy E.; Kennedy, M. John; Rogers, Mark T.; Porteous, Mary E.; Morrison, Patrick J.; Platte, Radka; Davidson, Rosemarie; Hodgson, Shirley V.; Ellis, Steve; Cole, Trevor; Godwin, Andrew K.; Claes, Kathleen; Van Maerken, Tom; Meindl, Alfons; Gehrig, Andrea; Sutter, Christian; Engel, Christoph; Niederacher, Dieter; Steinemann, Doris; Plendl, Hansjoerg; Kast, Karin; Rhiem, Kerstin; Ditsch, Nina; Arnold, Norbert; Varon-Mateeva, Raymonda; Wappenschmidt, Barbara; Wang-Gohrke, Shan; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Delnatte, Capucine; Houdayer, Claude; Stoppa-Lyonnet, Dominique; Damiola, Francesca; Coupier, Isabelle; Barjhoux, Laure; Venat-Bouvet, Laurence; Golmard, Lisa; Boutry-Kryza, Nadia; Sinilnikova, Olga M.; Caron, Olivier; Pujol, Pascal; Mazoyer, Sylvie; Belotti, Muriel; Piedmonte, Marion; Friedlander, Michael L.; Rodriguez, Gustavo C.; Copeland, Larry J; de la Hoya, Miguel; Segura, Pedro Perez; Nevanlinna, Heli; Aittomäki, Kristiina; van Os, Theo A.M.; Meijers-Heijboer, Hanne E.J.; van der Hout, Annemarie H.; Vreeswijk, Maaike P.G.; Hoogerbrugge, Nicoline; Ausems, Margreet G.E.M.; van Doorn, Helena C.; Collée, J. Margriet; Olah, Edith; Diez, Orland; Blanco, Ignacio; Lazaro, Conxi; Brunet, Joan; Feliubadalo, Lidia; Cybulski, Cezary; Gronwald, Jacek; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Sukiennicki, Grzegorz; Arason, Adalgeir; Chiquette, Jocelyne; Teixeira, Manuel R.; Olswold, Curtis; Couch, Fergus J.; Lindor, Noralane M.; Wang, Xianshu; Szabo, Csilla I.; Offit, Kenneth; Corines, Marina; Jacobs, Lauren; Robson, Mark E.; Zhang, Liying; Joseph, Vijai; Berger, Andreas; Singer, Christian F.; Rappaport, Christine; Kaulich, Daphne Geschwantler; Pfeiler, Georg; Tea, Muy-Kheng M.; Phelan, Catherine M.; Greene, Mark H.; Mai, Phuong L.; Rennert, Gad; Mulligan, Anna Marie; Glendon, Gord; Tchatchou, Sandrine; Andrulis, Irene L.; Toland, Amanda Ewart; Bojesen, Anders; Pedersen, Inge Sokilde; Thomassen, Mads; Jensen, Uffe Birk; Laitman, Yael; Rantala, Johanna; von Wachenfeldt, Anna; Ehrencrona, Hans; Askmalm, Marie Stenmark; Borg, Åke; Kuchenbaecker, Karoline B.; McGuffog, Lesley; Barrowdale, Daniel; Healey, Sue; Lee, Andrew; Pharoah, Paul D.P.; Chenevix-Trench, Georgia; Antoniou, Antonis C.; Friedman, Eitan

2014-01-01

Background BRCA1 and BRCA2 mutation carriers are at substantially increased risk for developing breast and ovarian cancer. The incomplete penetrance coupled with the variable age at diagnosis in carriers of the same mutation suggests the existence of genetic and non-genetic modifying factors. In this study we evaluated the putative role of variants in many candidate modifier genes. Methods Genotyping data from 15,252 BRCA1 and 8,211 BRCA2 mutation carriers, for known variants (n=3,248) located within or around 445 candidate genes, were available through the iCOGS custom-designed array. Breast and ovarian cancer association analysis was performed within a retrospective cohort approach. Results The observed p-values of association ranged between 0.005-1.000. None of the variants was significantly associated with breast or ovarian cancer risk in either BRCA1 or BRCA2 mutation carriers, after multiple testing adjustments. Conclusion There is little evidence that any of the evaluated candidate variants act as modifiers of breast and/or ovarian cancer risk in BRCA1 or BRCA2 mutation carriers. Impact Genome-wide association studies have been more successful at identifying genetic modifiers of BRCA1/2 penetrance than candidate gene studies. PMID:25336561

Dry powder inhaler formulation of lipid-polymer hybrid nanoparticles via electrostatically-driven nanoparticle assembly onto microscale carrier particles.

PubMed

Yang, Yue; Cheow, Wean Sin; Hadinoto, Kunn

2012-09-15

Lipid-polymer hybrid nanoparticles have emerged as promising nanoscale carriers of therapeutics as they combine the attractive characteristics of liposomes and polymers. Herein we develop dry powder inhaler (DPI) formulation of hybrid nanoparticles composed of poly(lactic-co-glycolic acid) and soybean lecithin as the polymer and lipid constituents, respectively. The hybrid nanoparticles are transformed into inhalable microscale nanocomposite structures by a novel technique based on electrostatically-driven adsorption of nanoparticles onto polysaccharide carrier particles, which eliminates the drawbacks of conventional techniques based on controlled drying (e.g. nanoparticle-specific formulation, low yield). First, we engineer polysaccharide carrier particles made up of chitosan cross-linked with tripolyphosphate and dextran sulphate to exhibit the desired aerosolization characteristics and physical robustness. Second, we investigate the effects of nanoparticle to carrier mass ratio and salt inclusion on the adsorption efficiency, in terms of the nanoparticle loading and yield, from which the optimal formulation is determined. Desorption of the nanoparticles from the carrier particles in phosphate buffer saline is also examined. Lastly, we characterize aerosolization efficiency of the nanocomposite product in vitro, where the emitted dose and respirable fraction are found to be comparable to the values of conventional DPI formulations. Copyright © 2012 Elsevier B.V. All rights reserved.

Memory Performance and fMRI Signal in Presymptomatic Familial Alzheimer’s Disease

PubMed Central

Braskie, Meredith N.; Medina, Luis D.; Rodriguez-Agudelo, Yaneth; Geschwind, Daniel H.; Macias-Islas, Miguel Angel; Thompson, Paul M.; Cummings, Jeffrey L.; Bookheimer, Susan Y.; Ringman, John M.

2013-01-01

Rare autosomal dominant mutations result in familial Alzheimer’s disease (FAD) with a relatively consistent age of onset within families. This provides an estimate of years until disease onset (relative age) in mutation carriers. Increased AD risk has been associated with differences in functional magnetic resonance imaging (fMRI) activity during memory tasks, but most of these studies have focused on possession of apolipoprotein E allele 4 (APOE4), a risk factor, but not causative variant, of late-onset AD. Evaluation of fMRI activity in presymptomatic FAD mutation carriers versus noncarriers provides insight into preclinical changes in those who will certainly develop AD in a prescribed period of time. Adults from FAD mutation-carrying families (nine mutation carriers, eight noncarriers) underwent fMRI scanning while performing a memory task. We examined fMRI signal differences between carriers and noncarriers, and how signal related to fMRI task performance within mutation status group, controlling for relative age and education. Mutation noncarriers had greater retrieval period activity than carriers in several AD-relevant regions, including the left hippocampus. Better performing noncarriers showed greater encoding period activity including in the parahippocampal gyrus. Poorer performing carriers showed greater retrieval period signal, including in the frontal and temporal lobes, suggesting underlying pathological processes. PMID:22806961

Candidate genetic modifiers for breast and ovarian cancer risk in BRCA1 and BRCA2 mutation carriers.

PubMed

Peterlongo, Paolo; Chang-Claude, Jenny; Moysich, Kirsten B; Rudolph, Anja; Schmutzler, Rita K; Simard, Jacques; Soucy, Penny; Eeles, Rosalind A; Easton, Douglas F; Hamann, Ute; Wilkening, Stefan; Chen, Bowang; Rookus, Matti A; Schmidt, Marjanka K; van der Baan, Frederieke H; Spurdle, Amanda B; Walker, Logan C; Lose, Felicity; Maia, Ana-Teresa; Montagna, Marco; Matricardi, Laura; Lubinski, Jan; Jakubowska, Anna; Gómez Garcia, Encarna B; Olopade, Olufunmilayo I; Nussbaum, Robert L; Nathanson, Katherine L; Domchek, Susan M; Rebbeck, Timothy R; Arun, Banu K; Karlan, Beth Y; Orsulic, Sandra; Lester, Jenny; Chung, Wendy K; Miron, Alex; Southey, Melissa C; Goldgar, David E; Buys, Saundra S; Janavicius, Ramunas; Dorfling, Cecilia M; van Rensburg, Elizabeth J; Ding, Yuan Chun; Neuhausen, Susan L; Hansen, Thomas V O; Gerdes, Anne-Marie; Ejlertsen, Bent; Jønson, Lars; Osorio, Ana; Martínez-Bouzas, Cristina; Benitez, Javier; Conway, Edye E; Blazer, Kathleen R; Weitzel, Jeffrey N; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Scuvera, Giulietta; Barile, Monica; Ficarazzi, Filomena; Mariette, Frederique; Fortuzzi, Stefano; Viel, Alessandra; Giannini, Giuseppe; Papi, Laura; Martayan, Aline; Tibiletti, Maria Grazia; Radice, Paolo; Vratimos, Athanassios; Fostira, Florentia; Garber, Judy E; Donaldson, Alan; Brewer, Carole; Foo, Claire; Evans, D Gareth R; Frost, Debra; Eccles, Diana; Brady, Angela; Cook, Jackie; Tischkowitz, Marc; Adlard, Julian; Barwell, Julian; Walker, Lisa; Izatt, Louise; Side, Lucy E; Kennedy, M John; Rogers, Mark T; Porteous, Mary E; Morrison, Patrick J; Platte, Radka; Davidson, Rosemarie; Hodgson, Shirley V; Ellis, Steve; Cole, Trevor; Godwin, Andrew K; Claes, Kathleen; Van Maerken, Tom; Meindl, Alfons; Gehrig, Andrea; Sutter, Christian; Engel, Christoph; Niederacher, Dieter; Steinemann, Doris; Plendl, Hansjoerg; Kast, Karin; Rhiem, Kerstin; Ditsch, Nina; Arnold, Norbert; Varon-Mateeva, Raymonda; Wappenschmidt, Barbara; Wang-Gohrke, Shan; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Delnatte, Capucine; Houdayer, Claude; Stoppa-Lyonnet, Dominique; Damiola, Francesca; Coupier, Isabelle; Barjhoux, Laure; Venat-Bouvet, Laurence; Golmard, Lisa; Boutry-Kryza, Nadia; Sinilnikova, Olga M; Caron, Olivier; Pujol, Pascal; Mazoyer, Sylvie; Belotti, Muriel; Piedmonte, Marion; Friedlander, Michael L; Rodriguez, Gustavo C; Copeland, Larry J; de la Hoya, Miguel; Segura, Pedro Perez; Nevanlinna, Heli; Aittomäki, Kristiina; van Os, Theo A M; Meijers-Heijboer, Hanne E J; van der Hout, Annemarie H; Vreeswijk, Maaike P G; Hoogerbrugge, Nicoline; Ausems, Margreet G E M; van Doorn, Helena C; Collée, J Margriet; Olah, Edith; Diez, Orland; Blanco, Ignacio; Lazaro, Conxi; Brunet, Joan; Feliubadalo, Lidia; Cybulski, Cezary; Gronwald, Jacek; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Sukiennicki, Grzegorz; Arason, Adalgeir; Chiquette, Jocelyne; Teixeira, Manuel R; Olswold, Curtis; Couch, Fergus J; Lindor, Noralane M; Wang, Xianshu; Szabo, Csilla I; Offit, Kenneth; Corines, Marina; Jacobs, Lauren; Robson, Mark E; Zhang, Liying; Joseph, Vijai; Berger, Andreas; Singer, Christian F; Rappaport, Christine; Kaulich, Daphne Geschwantler; Pfeiler, Georg; Tea, Muy-Kheng M; Phelan, Catherine M; Greene, Mark H; Mai, Phuong L; Rennert, Gad; Mulligan, Anna Marie; Glendon, Gord; Tchatchou, Sandrine; Andrulis, Irene L; Toland, Amanda Ewart; Bojesen, Anders; Pedersen, Inge Sokilde; Thomassen, Mads; Jensen, Uffe Birk; Laitman, Yael; Rantala, Johanna; von Wachenfeldt, Anna; Ehrencrona, Hans; Askmalm, Marie Stenmark; Borg, Åke; Kuchenbaecker, Karoline B; McGuffog, Lesley; Barrowdale, Daniel; Healey, Sue; Lee, Andrew; Pharoah, Paul D P; Chenevix-Trench, Georgia; Antoniou, Antonis C; Friedman, Eitan

2015-01-01

BRCA1 and BRCA2 mutation carriers are at substantially increased risk for developing breast and ovarian cancer. The incomplete penetrance coupled with the variable age at diagnosis in carriers of the same mutation suggests the existence of genetic and nongenetic modifying factors. In this study, we evaluated the putative role of variants in many candidate modifier genes. Genotyping data from 15,252 BRCA1 and 8,211 BRCA2 mutation carriers, for known variants (n = 3,248) located within or around 445 candidate genes, were available through the iCOGS custom-designed array. Breast and ovarian cancer association analysis was performed within a retrospective cohort approach. The observed P values of association ranged between 0.005 and 1.000. None of the variants was significantly associated with breast or ovarian cancer risk in either BRCA1 or BRCA2 mutation carriers, after multiple testing adjustments. There is little evidence that any of the evaluated candidate variants act as modifiers of breast and/or ovarian cancer risk in BRCA1 or BRCA2 mutation carriers. Genome-wide association studies have been more successful at identifying genetic modifiers of BRCA1/2 penetrance than candidate gene studies. ©2014 American Association for Cancer Research.

The BDNF Val66Met Polymorphism Influences Reading Ability and Patterns of Neural Activation in Children

PubMed Central

Jasińska, Kaja K.; Molfese, Peter J.; Kornilov, Sergey A.; Mencl, W. Einar; Frost, Stephen J.; Lee, Maria; Pugh, Kenneth R.; Grigorenko, Elena L.; Landi, Nicole

2016-01-01

Understanding how genes impact the brain’s functional activation for learning and cognition during development remains limited. We asked whether a common genetic variant in the BDNF gene (the Val66Met polymorphism) modulates neural activation in the young brain during a critical period for the emergence and maturation of the neural circuitry for reading. In animal models, the bdnf variation has been shown to be associated with the structure and function of the developing brain and in humans it has been associated with multiple aspects of cognition, particularly memory, which are relevant for the development of skilled reading. Yet, little is known about the impact of the Val66Met polymorphism on functional brain activation in development, either in animal models or in humans. Here, we examined whether the BDNF Val66Met polymorphism (dbSNP rs6265) is associated with children’s (age 6–10) neural activation patterns during a reading task (n = 81) using functional magnetic resonance imaging (fMRI), genotyping, and standardized behavioral assessments of cognitive and reading development. Children homozygous for the Val allele at the SNP rs6265 of the BDNF gene outperformed Met allele carriers on reading comprehension and phonological memory, tasks that have a strong memory component. Consistent with these behavioral findings, Met allele carriers showed greater activation in reading–related brain regions including the fusiform gyrus, the left inferior frontal gyrus and left superior temporal gyrus as well as greater activation in the hippocampus during a word and pseudoword reading task. Increased engagement of memory and spoken language regions for Met allele carriers relative to Val/Val homozygotes during reading suggests that Met carriers have to exert greater effort required to retrieve phonological codes. PMID:27551971

The BDNF Val66Met Polymorphism Influences Reading Ability and Patterns of Neural Activation in Children.

PubMed

Jasińska, Kaja K; Molfese, Peter J; Kornilov, Sergey A; Mencl, W Einar; Frost, Stephen J; Lee, Maria; Pugh, Kenneth R; Grigorenko, Elena L; Landi, Nicole

2016-01-01

Understanding how genes impact the brain's functional activation for learning and cognition during development remains limited. We asked whether a common genetic variant in the BDNF gene (the Val66Met polymorphism) modulates neural activation in the young brain during a critical period for the emergence and maturation of the neural circuitry for reading. In animal models, the bdnf variation has been shown to be associated with the structure and function of the developing brain and in humans it has been associated with multiple aspects of cognition, particularly memory, which are relevant for the development of skilled reading. Yet, little is known about the impact of the Val66Met polymorphism on functional brain activation in development, either in animal models or in humans. Here, we examined whether the BDNF Val66Met polymorphism (dbSNP rs6265) is associated with children's (age 6-10) neural activation patterns during a reading task (n = 81) using functional magnetic resonance imaging (fMRI), genotyping, and standardized behavioral assessments of cognitive and reading development. Children homozygous for the Val allele at the SNP rs6265 of the BDNF gene outperformed Met allele carriers on reading comprehension and phonological memory, tasks that have a strong memory component. Consistent with these behavioral findings, Met allele carriers showed greater activation in reading-related brain regions including the fusiform gyrus, the left inferior frontal gyrus and left superior temporal gyrus as well as greater activation in the hippocampus during a word and pseudoword reading task. Increased engagement of memory and spoken language regions for Met allele carriers relative to Val/Val homozygotes during reading suggests that Met carriers have to exert greater effort required to retrieve phonological codes.

Direct Effect of Dielectric Surface Energy on Carrier Transport in Organic Field-Effect Transistors.

PubMed

Zhou, Shujun; Tang, Qingxin; Tian, Hongkun; Zhao, Xiaoli; Tong, Yanhong; Barlow, Stephen; Marder, Seth R; Liu, Yichun

2018-05-09

The understanding of the characteristics of gate dielectric that leads to optimized carrier transport remains controversial, and the conventional studies applied organic semiconductor thin films, which introduces the effect of dielectric on the growth of the deposited semiconductor thin films and hence only can explore the indirect effects. Here, we introduce pregrown organic single crystals to eliminate the indirect effect (semiconductor growth) in the conventional studies and to undertake an investigation of the direct effect of dielectric on carrier transport. It is shown that the matching of the polar and dispersive components of surface energy between semiconductor and dielectric is favorable for higher mobility. This new empirical finding may show the direct relationship between dielectric and carrier transport for the optimized mobility of organic field-effect transistors and hence show a promising potential for the development of next-generation high-performance organic electronic devices.

The Automated Logistics Element Planning System (ALEPS)

NASA Technical Reports Server (NTRS)

Schwaab, Douglas G.

1992-01-01

ALEPS, which is being developed to provide the SSF program with a computer system to automate logistics resupply/return cargo load planning and verification, is presented. ALEPS will make it possible to simultaneously optimize both the resupply flight load plan and the return flight reload plan for any of the logistics carriers. In the verification mode ALEPS will support the carrier's flight readiness reviews and control proper execution of the approved plans. It will also support the SSF inventory management system by providing electronic block updates to the inventory database on the cargo arriving at or departing the station aboard a logistics carrier. A prototype drawer packing algorithm is described which is capable of generating solutions for 3D packing of cargo items into a logistics carrier storage accommodation. It is concluded that ALEPS will provide the capability to generate and modify optimized loading plans for the logistics elements fleet.

Development of Energy-Saving Devices for a 20,000DWT River-Sea Bulk Carrier

NASA Astrophysics Data System (ADS)

Chen, Kunpeng; Gao, Yuling; Huang, Zhenping; Dong, Guoxiang

2018-05-01

A reduction of fuel consumption and an increase in efficiency are currently required for river-sea bulk carriers. Pre-swirl and ducted stators are widely used devices in the industry and efficiency gains can be obtained for single-screw and twin-screw vessels. Based on the hydrodynamic characteristics of the 20,000DWT river-sea bulk carrier, in this study, we proposed, designed, and tested a series of pre-swirl energy-saving devices (ESDs). The experimental results demonstrate that the proposed ESDs improved the propulsive efficiency and reduced the delivered power. The results confirm the success of our ESD for the 20,000DWT river-sea bulk carrier. We validated the role of Reynolds-averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) in the twin-skeg river-sea vessel ESD design and found the circumferential arrangement and number of stators to be important factors in the design process.

Trapping of the Enoyl-Acyl Carrier Protein Reductase–Acyl Carrier Protein Interaction

PubMed Central

Tallorin, Lorillee; Finzel, Kara; Nguyen, Quynh G.; Beld, Joris; La Clair, James J.; Burkart, Michael D.

2016-01-01

An ideal target for metabolic engineering, fatty acid biosynthesis remains poorly understood on a molecular level. These carrier protein-dependent pathways require fundamental protein–protein interactions to guide reactivity and processivity, and their control has become one of the major hurdles in successfully adapting these biological machines. Our laboratory has developed methods to prepare acyl carrier proteins (ACPs) loaded with substrate mimetics and cross-linkers to visualize and trap interactions with partner enzymes, and we continue to expand the tools for studying these pathways. We now describe application of the slow-onset, tight-binding inhibitor triclosan to explore the interactions between the type II fatty acid ACP from Escherichia coli, AcpP, and its corresponding enoyl-ACP reductase, FabI. We show that the AcpP–triclosan complex demonstrates nM binding, inhibits in vitro activity, and can be used to isolate FabI in complex proteomes. PMID:26938266

Targeted delivery of anti-tuberculosis drugs to macrophages: targeting mannose receptors

NASA Astrophysics Data System (ADS)

Filatova, L. Yu; Klyachko, N. L.; Kudryashova, E. V.

2018-04-01

The development of systems for targeted delivery of anti-tuberculosis drugs is a challenge of modern biotechnology. Currently, these drugs are encapsulated in a variety of carriers such as liposomes, polymers, emulsions and so on. Despite successful in vitro testing of these systems, virtually no success was achieved in vivo, because of low accessibility of the foci of infection located in alveolar macrophage cells. A promising strategy for increasing the efficiency of therapeutic action of anti-tuberculosis drugs is to encapsulate the agents into mannosylated carriers targeting the mannose receptors of alveolar macrophages. The review addresses the methods for modification of drug substance carriers, such as liposomes and biodegradable polymers, with mannose residues. The use of mannosylated carriers to deliver anti-tuberculosis agents increases the drug circulation time in the blood stream and increases the drug concentration in alveolar macrophage cells. The bibliography includes 113 references.

Epoxy Chip-in-Carrier Integration and Screen-Printed Metalization for Multichannel Microfluidic Lab-on-CMOS Microsystems.

PubMed

Li, Lin; Yin, Heyu; Mason, Andrew J

2018-04-01

The integration of biosensors, microfluidics, and CMOS instrumentation provides a compact lab-on-CMOS microsystem well suited for high throughput measurement. This paper describes a new epoxy chip-in-carrier integration process and two planar metalization techniques for lab-on-CMOS that enable on-CMOS electrochemical measurement with multichannel microfluidics. Several design approaches with different fabrication steps and materials were experimentally analyzed to identify an ideal process that can achieve desired capability with high yield and low material and tool cost. On-chip electrochemical measurements of the integrated assembly were performed to verify the functionality of the chip-in-carrier packaging and its capability for microfluidic integration. The newly developed CMOS-compatible epoxy chip-in-carrier process paves the way for full implementation of many lab-on-CMOS applications with CMOS ICs as core electronic instruments.

Soft Coulomb gap and asymmetric scaling towards metal-insulator quantum criticality in multilayer MoS2.

PubMed

Moon, Byoung Hee; Bae, Jung Jun; Joo, Min-Kyu; Choi, Homin; Han, Gang Hee; Lim, Hanjo; Lee, Young Hee

2018-05-24

Quantum localization-delocalization of carriers are well described by either carrier-carrier interaction or disorder. When both effects come into play, however, a comprehensive understanding is not well established mainly due to complexity and sparse experimental data. Recently developed two-dimensional layered materials are ideal in describing such mesoscopic critical phenomena as they have both strong interactions and disorder. The transport in the insulating phase is well described by the soft Coulomb gap picture, which demonstrates the contribution of both interactions and disorder. Using this picture, we demonstrate the critical power law behavior of the localization length, supporting quantum criticality. We observe asymmetric critical exponents around the metal-insulator transition through temperature scaling analysis, which originates from poor screening in insulating regime and conversely strong screening in metallic regime due to free carriers. The effect of asymmetric scaling behavior is weakened in monolayer MoS 2 due to a dominating disorder.

EDRN Longitudinal Serum Biorepository — EDRN Public Portal

Cancer.gov

Four percent of EDRN Registry mutation carriers developed cancer within a year after beginning follow-up in this registry; within 2 years, 10% had developed cancer. Within 2 years, 17% had developed either a cancer or a pre-malignant lesion (e.g. adenoma). Our goal is to recruit 265 mutation carriers from the EDRN High Risk Registry and Hereditary Cancer Center for the Longitudinal Serum Biorepository (LSB). Based on the cancer rates observed to date in the EDRN Registry, four years of follow-up in a group of this size would be expected to yield 53 invasive and in situ cancers and 37 benign premalignant lesions. All subjects in the serum biorepository (1)have signed consent (2) are counseled carriers (APC, BRCA1, BRCA2, CDH1, CDKN2A, MLH1, MSH2, MSH6) and (3) are enrolled in family studies through CU's Department of Preventive Medicine and/or are enrolled in the EDRN High Risk Registry. Post specimen medical history is collected annually. Serum and plasma are aliquoted for respository storage and stored in labeled cryovials in an ultra low temperature (-86C) freezer. Specimens in the LSB are available for use in EDRN biomarker development and validation studies.

Effects of trap density on drain current LFN and its model development for E-mode GaN MOS-HEMT

NASA Astrophysics Data System (ADS)

Panda, D. K.; Lenka, T. R.

2017-12-01

In this paper the drain current low-frequency noise (LFN) of E-mode GaN MOS-HEMT is investigated for different gate insulators such as SiO2, Al2O3/Ga2O3/GdO3, HfO2/SiO2, La2O3/SiO2 and HfO2 with different trap densities by IFM based TCAD simulation. In order to analyze this an analytical model of drain current low frequency noise is developed. The model is developed by considering 2DEG carrier fluctuations, mobility fluctuations and the effects of 2DEG charge carrier fluctuations on the mobility. In the study of different gate insulators it is observed that carrier fluctuation is the dominant low frequency noise source and the non-uniform exponential distribution is critical to explain LFN behavior, so the analytical model is developed by considering uniform distribution of trap density. The model is validated with available experimental data from literature. The effect of total number of traps and gate length scaling on this low frequency noise due to different gate dielectrics is also investigated.

Closed-loop carrier phase synchronization techniques motivated by likelihood functions

NASA Technical Reports Server (NTRS)

Tsou, H.; Hinedi, S.; Simon, M.

1994-01-01

This article reexamines the notion of closed-loop carrier phase synchronization motivated by the theory of maximum a posteriori phase estimation with emphasis on the development of new structures based on both maximum-likelihood and average-likelihood functions. The criterion of performance used for comparison of all the closed-loop structures discussed is the mean-squared phase error for a fixed-loop bandwidth.

Skylab communications carrier 16536G and filter bypass adapter assembly 12535G. [development of communications equipment for use with Skylab spacecraft

NASA Technical Reports Server (NTRS)

1974-01-01

Communications equipment for use with the Skylab project is examined to show compliance with contract requirements. The items of equipment considered are: (1) communications carrier assemblies, (2) filter bypass adapter assemblies, and (3) sub-assemblies, parts, and repairs. Additional information is provided concerning contract requirements, test requirements, and failure investigation actions.

Co-existence of breast and ovarian cancers in BRCA germ-line mutation carriers

PubMed Central

Dilawari, A; Cangiarella, J; Smith, J; Huang, A; Downey, A; Muggia, F

2008-01-01

The co-existence of breast and ovarian cancers in the same individual should raise suspicion of a hereditary process. Patients with either BRCA1 or BRCA2 germ-line mutations have an average risk of 39% and 11% respectively of developing ovarian cancer by the age of 70; they have a risk of 35–85% of developing breast cancer in their lifetime. We report here unusual pathologic features in a BRCA2 germ-line mutation carrier recently diagnosed with synchronous breast and ovarian cancers, and summarize the findings in six other women who were diagnosed with ovarian cancer either simultaneously with the diagnosis of breast cancer or at varying times after the diagnosis. While in most instances this may be a coincidental occurrence in highly susceptible individuals, the patient we highlight raises the provocative hypothesis that at times breast cancer metastasizes to the ovaries of mutation carriers and stimulates the development of an ovarian cancer as well as other cancers. In addition, these ovarian cancers may have different mechanisms of metastases predisposing them to travel to unusual sites. PMID:22275985

Physical and chemical stability of nanostructured lipid drug carriers (NLC) based on natural lipids from Baikal region (Siberia, Russia).

PubMed

Averina, E S; Müller, R H; Popov, D V; Radnaeva, L D

2011-05-01

At the turn of the millennium, a new generation of lipid nanoparticles for pharmacology was developed, nanostructured lipid carriers (NLC). The features of NLC structure which allow the inclusion of natural biologically active lipids in the NLC matrix open a wide prospect for the creation of high performance drug carriers. In this study NLC formulations were developed based on natural lipids from the Siberia region (Russia): fish oil from Lake Baikal fish; polyunsaturated fatty acid fractions and monounsaturated and saturated fatty acid fractions from fish oil and Siberian pine seed oil. Formulation parameters of NLC such as as type of surfactant and storage conditions were evaluated. The data obtained indicated high physical stability of NLC formulated on the basis of pure fish oil stabilized by Tween 80 and NLC formulated on the basis of free fatty acids stabilized by Poloxamer 188. The good chemical stability of the lipid matrix and the high concentrations of the biologically active polyunsaturated fatty acids in the NLC developed open wide prospects for their use in pharmaceutics and cosmetics.

Joint effect of MCP-1 genotype GG and MMP-1 genotype 2G/2G increases the likelihood of developing pulmonary tuberculosis in BCG-vaccinated individuals.

PubMed

Ganachari, Malathesha; Ruiz-Morales, Jorge A; Gomez de la Torre Pretell, Juan C; Dinh, Jeffrey; Granados, Julio; Flores-Villanueva, Pedro O

2010-01-25

We previously reported that the -2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB) in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the -1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC) analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the -2518 MCP-1 genotype GG and the -1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1, which enhances the induction of MMP-1 production by M. tuberculosis-sonicate antigens to higher levels than in carriers of the other two-locus MCP-1 MMP-1 genotypes studied. This notion was supported by in vitro experiments and luciferase based promoter activity assay. MMP-1 may destabilize granuloma formation and promote tissue damage and disease progression early in the infection. Our findings may foster the development of new and personalized therapeutic approaches targeting MCP-1 and/or MMP-1.

Joint Effect of MCP-1 Genotype GG and MMP-1 Genotype 2G/2G Increases the Likelihood of Developing Pulmonary Tuberculosis in BCG-Vaccinated Individuals

PubMed Central

Ganachari, Malathesha; Ruiz-Morales, Jorge A.; Gomez de la Torre Pretell, Juan C.; Dinh, Jeffrey; Granados, Julio; Flores-Villanueva, Pedro O.

2010-01-01

We previously reported that the – 2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB) in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the – 1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC) analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the – 2518 MCP-1 genotype GG and the – 1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1, which enhances the induction of MMP-1 production by M. tuberculosis-sonicate antigens to higher levels than in carriers of the other two-locus MCP-1 MMP-1 genotypes studied. This notion was supported by in vitro experiments and luciferase based promoter activity assay. MMP-1 may destabilize granuloma formation and promote tissue damage and disease progression early in the infection. Our findings may foster the development of new and personalized therapeutic approaches targeting MCP-1 and/or MMP-1. PMID:20111728

Carrier trajectory tracking equations for Simple-band Monte Carlo simulation of avalanche multiplication processes

NASA Astrophysics Data System (ADS)

Ong, J. S. L.; Charin, C.; Leong, J. H.

2017-12-01

Avalanche photodiodes (APDs) with steep electric field gradients generally have low excess noise that arises from carrier multiplication within the internal gain of the devices, and the Monte Carlo (MC) method is among popular device simulation tools for such devices. However, there are few articles relating to carrier trajectory modeling in MC models for such devices. In this work, a set of electric-field-gradient-dependent carrier trajectory tracking equations are developed and used to update the positions of carriers along the path during Simple-band Monte Carlo (SMC) simulations of APDs with non-uniform electric fields. The mean gain and excess noise results obtained from the SMC model employing these equations show good agreement with the results reported for a series of silicon diodes, including a p+n diode with steep electric field gradients. These results confirm the validity and demonstrate the feasibility of the trajectory tracking equations applied in SMC models for simulating mean gain and excess noise in APDs with non-uniform electric fields. Also, the simulation results of mean gain, excess noise, and carrier ionization positions obtained from the SMC model of this work agree well with those of the conventional SMC model employing the concept of a uniform electric field within a carrier free-flight. These results demonstrate that the electric field variation within a carrier free-flight has an insignificant effect on the predicted mean gain and excess noise results. Therefore, both the SMC model of this work and the conventional SMC model can be used to predict the mean gain and excess noise in APDs with highly non-uniform electric fields.

Smoking and physical inactivity increase cancer prevalence in BRCA-1 and BRCA-2 mutation carriers: results from a retrospective observational analysis.

PubMed

Grill, Sabine; Yahiaoui-Doktor, Maryam; Dukatz, Ricarda; Lammert, Jacqueline; Ullrich, Mirjam; Engel, Christoph; Pfeifer, Katharina; Basrai, Maryam; Siniatchkin, Michael; Schmidt, Thorsten; Weisser, Burkhard; Rhiem, Kerstin; Ditsch, Nina; Schmutzler, Rita; Bischoff, Stephan C; Halle, Martin; Kiechle, Marion

2017-12-01

The aim of this analysis in a pilot study population was to investigate whether we can verify seemingly harmful lifestyle factors such as nicotine and alcohol indulgence, obesity, and physical inactivity, as well as a low socioeconomic status for increased cancer prevalence in a cohort of BRCA 1 and 2 mutation carriers. The analysis data are derived from 68 participants of the lifestyle intervention study LIBRE-1, a randomized, prospective trial that aimed to test the feasibility of a lifestyle modification in BRCA 1 and 2 mutation carriers. At study entry, factors such as medical history, lifestyle behavior, and socioeconomic status were retrospectively documented by interview and the current BMI was determined by clinical examination. The baseline measurements were compared within the cohort, and presented alongside reference values for the German population. Study participants indicating a higher physical activity during their adolescence showed a significantly lower cancer prevalence (p = 0.019). A significant difference in cancer occurrence was observed in those who smoked prior to the disease, and those who did not smoke (p < 0.001). Diseased mutation carriers tended to have a lower BMI compared to non-diseased mutation carriers (p = 0.079), whereas non-diseased revealed a significantly higher physical activity level than diseased mutation carriers (p = 0.046). The present data in this small cohort of 68 mutation carriers suggest that smoking and low physical activity during adolescence are risk factors for developing breast cancer in women with BRCA1 or BRCA2 mutation. Further data of the ongoing LIBRE 2 study are necessary to confirm these findings in a larger cohort of 600 mutation carriers.

Carrier dynamics and surface vibration-assisted Auger recombination in porous silicon

NASA Astrophysics Data System (ADS)

Zakar, Ammar; Wu, Rihan; Chekulaev, Dimitri; Zerova, Vera; He, Wei; Canham, Leigh; Kaplan, Andrey

2018-04-01

Excitation and recombination dynamics of the photoexcited charge carriers in porous silicon membranes were studied using a femtosecond pump-probe technique. Near-infrared pulses (800 nm, 60 fs) were used for the pump while, for the probe, we employed different wavelengths in the range between 3.4 and 5 μ m covering the medium wavelength infrared range. The data acquired in these experiments consist of simultaneous measurements of the transmittance and reflectance as a function of the delay time between the pump and probe for different pump fluences and probe wavelengths. To evaluate the results, we developed an optical model based on the two-dimensional Maxwell-Garnett formula, incorporating the free-carrier Drude contribution and nonuniformity of the excitation by the Wentzel-Kramers-Brillouin model. This model allowed the retrieval of information about the carrier density as a function of the pump fluence, time, and wavelength. The carrier density data were analyzed to reveal that the recombination dynamics is governed by Shockley-Read-Hall and Auger processes, whereas the diffusion has an insignificant contribution. We show that, in porous silicon samples, the Auger recombination process is greatly enhanced at the wavelength corresponding to the infrared-active vibrational modes of the molecular impurities on the surface of the pores. This observation of surface-vibration-assisted Auger recombination is not only for porous silicon in particular, but for low-dimension and bulk semiconductors in general. We estimate the time constants of Shockley-Read-Hall and Auger processes, and demonstrate their wavelength dependence for the excited carrier density in the range of 1018-10191 /cm3 . We demonstrate that both processes are enhanced by up to three orders of magnitude with respect to the bulk counterpart. In addition, we provide a plethora of the physical parameters evaluated from the experimental data, such as the dielectric function and its dependence on the injection level of the free carriers, charge-carrier scattering time related high-frequency conductivity, and the free-carrier absorption at the midwave infrared range.

Spatial relationship between Taenia solium tapeworm carriers and necropsy cyst burden in pigs

PubMed Central

Ayvar, Viterbo; Gamboa, Ricardo; Muro, Claudio; Moyano, Luz M.; Benavides, Victor; Flecker, Robert H.; Garcia, Hector H.; O’Neal, Seth E.

2017-01-01

Background Taenia solium, a parasite that affects humans and pigs, is the leading cause of preventable epilepsy in the developing world. Geographic hotspots of pigs testing positive for serologic markers of T. solium exposure have been observed surrounding the locations of human tapeworm carriers. This clustered pattern of seropositivity in endemic areas formed the basis for geographically targeted control interventions, which have been effective at reducing transmission. In this study, we further explore the spatial relationship between human tapeworm carriers and infected pigs using necroscopic examination as a quantitative gold-standard diagnostic to detect viable T. solium cyst infection in pigs. Methodology/Principal findings We performed necroscopic examinations on pigs from 7 villages in northern Peru to determine the number of viable T. solium cysts in each pig. Participating humans in the study villages were tested for T. solium tapeworm infection (i.e., taeniasis) with an ELISA coproantigen assay, and the distances from each pig to its nearest human tapeworm carrier were calculated. We assessed the relationship between proximity to a tapeworm carrier and the prevalence of light, moderate, and heavy cyst burden in pigs. The prevalence of pig infection was greatest within 50 meters of a tapeworm carrier and decreased monotonically as distance increased. Pigs living less than 50 meters from a human tapeworm carrier were 4.6 times more likely to be infected with at least one cyst than more distant pigs. Heavier cyst burdens, however, were not more strongly associated with proximity to tapeworm carriers than light cyst burdens. Conclusion/Significance Our study shows that human tapeworm carriers and pigs with viable T. solium cyst infection are geographically correlated in endemic areas. This finding supports control strategies that treat humans and pigs based on their proximity to other infected individuals. We did not, however, find sufficient evidence that heavier cyst burdens in pigs would serve as improved targets for geographically focused control interventions. PMID:28406898

Spatial relationship between Taenia solium tapeworm carriers and necropsy cyst burden in pigs.

PubMed

Pray, Ian W; Ayvar, Viterbo; Gamboa, Ricardo; Muro, Claudio; Moyano, Luz M; Benavides, Victor; Flecker, Robert H; Garcia, Hector H; O'Neal, Seth E

2017-04-01

Taenia solium, a parasite that affects humans and pigs, is the leading cause of preventable epilepsy in the developing world. Geographic hotspots of pigs testing positive for serologic markers of T. solium exposure have been observed surrounding the locations of human tapeworm carriers. This clustered pattern of seropositivity in endemic areas formed the basis for geographically targeted control interventions, which have been effective at reducing transmission. In this study, we further explore the spatial relationship between human tapeworm carriers and infected pigs using necroscopic examination as a quantitative gold-standard diagnostic to detect viable T. solium cyst infection in pigs. We performed necroscopic examinations on pigs from 7 villages in northern Peru to determine the number of viable T. solium cysts in each pig. Participating humans in the study villages were tested for T. solium tapeworm infection (i.e., taeniasis) with an ELISA coproantigen assay, and the distances from each pig to its nearest human tapeworm carrier were calculated. We assessed the relationship between proximity to a tapeworm carrier and the prevalence of light, moderate, and heavy cyst burden in pigs. The prevalence of pig infection was greatest within 50 meters of a tapeworm carrier and decreased monotonically as distance increased. Pigs living less than 50 meters from a human tapeworm carrier were 4.6 times more likely to be infected with at least one cyst than more distant pigs. Heavier cyst burdens, however, were not more strongly associated with proximity to tapeworm carriers than light cyst burdens. Our study shows that human tapeworm carriers and pigs with viable T. solium cyst infection are geographically correlated in endemic areas. This finding supports control strategies that treat humans and pigs based on their proximity to other infected individuals. We did not, however, find sufficient evidence that heavier cyst burdens in pigs would serve as improved targets for geographically focused control interventions.

A simplified method for determining heat of combustion of natural gas

NASA Technical Reports Server (NTRS)

Singh, Jag J.; Chegini, Hoshang; Mall, Gerald H.

1987-01-01

A simplified technique for determination of the heat of combustion of natural gas has been developed. It is a variation of the previously developed technique wherein the carrier air, in which the test sample was burnt, was oxygen enriched to adjust the mole fraction of oxygen in the combustion product gases up to that in the carrier air. The new technique eliminates the need for oxygen enrichment of the experimental mixtures and natural gas samples and has been found to predict their heats of combustion to an uncertainty of the order of 1 percent.

Functional gene polymorphisms in the serotonin system and traumatic life events modulate the neural basis of fear acquisition and extinction.

PubMed

Hermann, Andrea; Küpper, Yvonne; Schmitz, Anja; Walter, Bertram; Vaitl, Dieter; Hennig, Jürgen; Stark, Rudolf; Tabbert, Katharina

2012-01-01

Fear acquisition and extinction are crucial mechanisms in the etiology and maintenance of anxiety disorders. Moreover, they might play a pivotal role in conveying the influence of genetic and environmental factors on the development of a (more or less) stronger proneness for, or resilience against psychopathology. There are only few insights in the neurobiology of genetically and environmentally based individual differences in fear learning and extinction. In this functional magnetic resonance imaging study, 74 healthy subjects were investigated. These were invited according to 5-HTTLPR/rs25531 (S+ vs. L(A)L(A); triallelic classification) and TPH2 (G(-703)T) (T+ vs. T-) genotype. The aim was to investigate the influence of genetic factors and traumatic life events on skin conductance responses (SCRs) and neural responses (amygdala, insula, dorsal anterior cingulate cortex (dACC) and ventromedial prefrontal cortex (vmPFC)) during acquisition and extinction learning in a differential fear conditioning paradigm. Fear acquisition was characterized by stronger late conditioned and unconditioned responses in the right insula in 5-HTTLPR S-allele carriers. During extinction traumatic life events were associated with reduced amygdala activation in S-allele carriers vs. non-carriers. Beyond that, T-allele carriers of the TPH2 (G(-703)T) polymorphism with a higher number of traumatic life events showed enhanced responsiveness in the amygdala during acquisition and in the vmPFC during extinction learning compared with non-carriers. Finally, a combined effect of the two polymorphisms with higher responses in S- and T-allele carriers was found in the dACC during extinction. The results indicate an increased expression of conditioned, but also unconditioned fear responses in the insula in 5-HTTLPR S-allele carriers. A combined effect of the two polymorphisms on dACC activation during extinction might be associated with prolonged fear expression. Gene-by-environment interactions in amygdala and vmPFC activation may reflect a neural endophenotype translating genetic and adverse environmental influences into vulnerability for or resilience against developing affective psychopathology.

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.

Bimolecular recombination quenching in Langmuir Blodgett multilayers

NASA Astrophysics Data System (ADS)

Elliott, J. E.; Jeong, I. S.; Scott, K.; Donovan, K. J.; Wilson, E. G.

2000-11-01

A model is developed that describes bimolecular recombination of photogenerated carriers in two dimensional systems. Carriers are free to diffuse in two dimensions and undergo bimolecular recombination, while drifting under the influence of an electric field in the third dimension. The model describes a competition between carrier loss due to transiting and loss due to bimolecular recombination. This model of recombination quenching is then used to obtain information on microscopic parameters associated with photogeneration efficiency and charge transport in organic quantum wells formed from Langmuir Blodgett films of conjugated molecules. The ratio of the intralayer to interlayer tunneling rates is found along with the quantum efficiency for photocarrier generation for two bis-phthalocyanine amphiphilic molecules.

Hitchhiker-G: A new carrier system for attached shuttle payloads

NASA Technical Reports Server (NTRS)

Goldsmith, T. C.

1987-01-01

A new carrier system has been developed for economical and quick response flight of small attached payloads on the space shuttle. Hitchhiker-G can accommodate up to 750 lb. of customer payloads in canisters or mounted to an exposed plate. The carrier connects to the orbiter's electrical systems and provides up to six customers with standard electrical services including power, real time telemetry, and commands. A transparent data and command system concept is employed to allow the customer to easily use his own ground support equipment and personnel to control his payload during integration and flight operations. The first Hitchhiker-G was successfully flown in January 1986 on STS 61C.

World`s first SPB LNG carrier ``POLAR EAGLE``

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

Aoki, Eiji; Nakajima, Yoshiyuki; Yamada, Koichiro

1994-12-31

The world`s first Self-supporting Prismatic-shape IMO type B (SPB) LNG Carrier named ``POLAR EAGLE`` has been delivered to Phillips 66 Natural Gas Company and Marathon Oil Company in June, 1993. The cargo containment system installed onboard the vessel, SPB cargo containment system, was developed by Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI) and fully complies with IMO Gas Carrier Code for a type B independent tank. ``POLAR EAGLE`` was constructed in the authors` Aichi works and delivered 34 months after the contract of the vessel. Its performance was confirmed through various kinds of tests and inspections during construction of the vessel.more » Results of typical tests and inspections are introduced.« less

Collector modulation in high-voltage bipolar transistor in the saturation mode: Analytical approach

NASA Astrophysics Data System (ADS)

Dmitriev, A. P.; Gert, A. V.; Levinshtein, M. E.; Yuferev, V. S.

2018-04-01

A simple analytical model is developed, capable of replacing the numerical solution of a system of nonlinear partial differential equations by solving a simple algebraic equation when analyzing the collector resistance modulation of a bipolar transistor in the saturation mode. In this approach, the leakage of the base current into the emitter and the recombination of non-equilibrium carriers in the base are taken into account. The data obtained are in good agreement with the results of numerical calculations and make it possible to describe both the motion of the front of the minority carriers and the steady state distribution of minority carriers across the collector in the saturation mode.

Distribution of Localized States from Fine Analysis of Electron Spin Resonance Spectra in Organic Transistors

NASA Astrophysics Data System (ADS)

Matsui, Hiroyuki; Mishchenko, Andrei S.; Hasegawa, Tatsuo

2010-02-01

We developed a novel method for obtaining the distribution of trapped carriers over their degree of localization in organic transistors, based on the fine analysis of electron spin resonance spectra at low enough temperatures where all carriers are localized. To apply the method to pentacene thin-film transistors, we proved through continuous wave saturation experiments that all carriers are localized at below 50 K. We analyzed the spectra at 20 K and found that the major groups of traps comprise localized states having wave functions spanning around 1.5 and 5 molecules and a continuous distribution of states with spatial extent in the range between 6 and 20 molecules.

Distribution of localized states from fine analysis of electron spin resonance spectra in organic transistors.

PubMed

Matsui, Hiroyuki; Mishchenko, Andrei S; Hasegawa, Tatsuo

2010-02-05

We developed a novel method for obtaining the distribution of trapped carriers over their degree of localization in organic transistors, based on the fine analysis of electron spin resonance spectra at low enough temperatures where all carriers are localized. To apply the method to pentacene thin-film transistors, we proved through continuous wave saturation experiments that all carriers are localized at below 50 K. We analyzed the spectra at 20 K and found that the major groups of traps comprise localized states having wave functions spanning around 1.5 and 5 molecules and a continuous distribution of states with spatial extent in the range between 6 and 20 molecules.

Design of a 12-GHz multicarrier earth-terminal for satellite-CATV interconnection

NASA Technical Reports Server (NTRS)

Newman, B. A.; Singh, J. P.; Rosenbaum, F. J.

1971-01-01

The design and development of the front-end for a multi-carrier system that allows multiplex signal transmission from satellite-borne transponders is described. Detailed systems analyses provided down-converter specifications. The 12 GHz carrier down-converter uses waveguide, coaxial, and microstrip transmission line elements in its implementation. Mixing is accomplished in a single-ended coaxial mixer employing a field-replacable cartridge style diode.

Enhanced gene delivery to the lung using biodegradable polyunsaturated cationic phosphatidylcholine-detergent conjugates.

PubMed

Pierrat, Philippe; Kereselidze, Dimitri; Lux, Marie; Lebeau, Luc; Pons, Françoise

2016-09-10

Lung diseases are among the more representative causes of mortality and morbidity worldwide and gene therapy is considered as a promising therapeutic approach for their treatment. However the design of efficient nucleic acid carriers for airway administration still is a challenge and there is a pressing need for new developments in this field. Herein, new synthetic DNA carriers based on the conjugation of a phospholipid and C12E4, a nonionic detergent, are developed. DNA complexes with phosphatidylcholine-detergent conjugates are administered in mouse airways, and transgene expression and inflammatory activity as an index of toxicity are investigated as a function of time, DNA dose, and presence of helper and stealth lipids. Introduction of a biodegradable linker between the phosphatidylcholine and detergent moieties significantly attenuates the severity of inflammatory response that characterizes cationic lipid-mediated gene transfer. Concurrent introduction of polyunsaturated fatty acid chains in the carrier scaffold improves transgene expression and further reduces airway inflammation. Finally, the biodegradable phosphatidylcholine-detergent conjugates favorably compare to GL67A, the gold standard for DNA delivery to the airway that is currently under clinical evaluation. Our findings indicate that the lipid formulations described herein may have great potential as nucleic acid carriers for gene therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Near-field transport imaging applied to photovoltaic materials

DOE PAGES

Xiao, Chuanxiao; Jiang, Chun -Sheng; Moseley, John; ...

2017-05-26

We developed and applied a new analytical technique - near-field transport imaging (NF-TI or simply TI) - to photovoltaic materials. Charge-carrier transport is an important factor in solar cell performance, and TI is an innovative approach that integrates a scanning electron microscope with a near-field scanning optical microscope, providing the possibility to study luminescence associated with recombination and transport with high spatial resolution. In this paper, we describe in detail the technical barriers we had to overcome to develop the technique for routine application and the data-fitting procedure used to calculate minority-carrier diffusion length values. The diffusion length measured bymore » TI agrees well with the results calculated by time-resolved photoluminescence on well-controlled gallium arsenide (GaAs) thin-film samples. We report for the first time on measurements on thin-film cadmium telluride using this technique, including the determination of effective carrier diffusion length, as well as the first near-field imaging of the effect of a single localized defect on carrier transport and recombination in a GaAs heterostructure. Furthermore, by changing the scanning setup, we were able to demonstrate near-field cathodoluminescence (CL), and correlated the results with standard CL measurements. In conclusion, the TI technique shows great potential for mapping transport properties in solar cell materials with high spatial resolution.« less

APOE associated hemispheric asymmetry of entorhinal cortical thickness in aging and Alzheimer’s disease

PubMed Central

Donix, Markus; Burggren, Alison C.; Scharf, Maria; Marschner, Kira; Suthana, Nanthia A.; Siddarth, Prabha; Krupa, Allison K.; Jones, Michael; Martin-Harris, Laurel; Ercoli, Linda M.; Miller, Karen J.; Werner, Annett; von Kummer, Rüdiger; Sauer, Cathrin; Small, Gary W.; Holthoff, Vjera A.; Bookheimer, Susan Y.

2013-01-01

Across species structural and functional hemispheric asymmetry is a fundamental feature of the brain. Environmental and genetic factors determine this asymmetry during brain development and modulate its interaction with brain disorders. The e4 allele of the apolipoprotein E gene (APOE-4) is a risk factor for Alzheimer’s disease, associated with regionally specific effects on brain morphology and function during the life span. Furthermore, entorhinal and hippocampal hemispheric asymmetry could be modified by pathology during Alzheimer’s disease development. Using high-resolution magnetic resonance imaging and a cortical unfolding technique we investigated whether carrying the APOE-4 allele influences hemispheric asymmetry in the entorhinal cortex and the hippocampus among patients with Alzheimer’s disease as well as in middle-aged and older cognitively healthy individuals. APOE-4 carriers showed a thinner entorhinal cortex in the left hemisphere when compared with the right hemisphere across all participants. Non-carriers of the allele showed this asymmetry only in the patient group. Cortical thickness in the hippocampus did not vary between hemispheres among APOE-4 allele carriers and non-carriers. The APOE-4 allele modulates hemispheric asymmetry in entorhinal cortical thickness. Among Alzheimer’s disease patients, this asymmetry might be less dependent on the APOE genotype and a more general marker of incipient disease pathology. PMID:24080518

Carrier Plus: A sensor payload for Living With a Star Space Environment Testbed (LWS/SET)

NASA Technical Reports Server (NTRS)

Marshall, Cheryl J.; Moss, Steven; Howard, Regan; LaBel, Kenneth A.; Grycewicz, Tom; Barth, Janet L.; Brewer, Dana

2003-01-01

The Defense Threat Reduction Agency (DTR4) and National Aeronautics and Space Administration (NASA) Goddard Space Flight Center are collaborating to develop the Carrier Plus sensor experiment platform as a capability of the Space Environments Testbed (SET). The Space Environment Testbed (SET) provides flight opportunities for technology experiments as part of NASA's Living With a Star (LWS) program. The Carrier Plus will provide new capability to characterize sensor technologies such as state-of-the-art visible focal plane arrays (FPAs) in a natural space radiation environment. The technical objectives include on-orbit validation of recently developed FPA technologies and performance prediction methodologies, as well as characterization of the FPA radiation response to total ionizing dose damage, displacement damage and transients. It is expected that the sensor experiment will carry 4-6 FPAs and associated radiation correlative environment monitors (CEMs) for a 2006-2007 launch. Sensor technology candidates may include n- and p-charge coupled devices (CCDs), active pixel sensors (APS), and hybrid CMOS arrays. The presentation will describe the Carrier Plus goals and objectives, as well as provide details about the architecture and design. More information on the LWS program can be found at http://lws.gsfc.nasa.gov/. Business announcements for LWS/SET and program briefings are posted at http://lws-set.gsfc.nasa.gov

Synergistically enhanced selective intracellular uptake of anticancer drug carrier comprising folic acid-conjugated hydrogels containing magnetite nanoparticles

NASA Astrophysics Data System (ADS)

Kim, Haneul; Jo, Ara; Baek, Seulgi; Lim, Daeun; Park, Soon-Yong; Cho, Soo Kyung; Chung, Jin Woong; Yoon, Jinhwan

2017-01-01

Targeted drug delivery has long been extensively researched since drug delivery and release at the diseased site with minimum dosage realizes the effective therapy without adverse side effects. In this work, to achieve enhanced intracellular uptake of anticancer drug carriers for efficient chemo-therapy, we have designed targeted multifunctional anticancer drug carrier hydrogels. Temperature-responsive poly(N-isopropylacrylamide) (PNIPAm) hydrogel core containing superparamagnetic magnetite nanoparticles (MNP) were prepared using precipitation polymerization, and further polymerized with amine-functionalized copolymer shell to facilitate the conjugation of targeting ligand. Then, folic acid, specific targeting ligand for cervical cancer cell line (HeLa), was conjugated on the hydrogel surface, yielding the ligand conjugated hybrid hydrogels. We revealed that enhanced intracellular uptake by HeLa cells in vitro was enabled by both magnetic attraction and receptor-mediated endocytosis, which were contributed by MNP and folic acid, respectively. Furthermore, site-specific uptake of the developed carrier was confirmed by incubating with several other cell lines. Based on synergistically enhanced intracellular uptake, efficient cytotoxicity and apoptotic activity of HeLa cells incubated with anticancer drug loaded hybrid hydrogels were successfully achieved. The developed dual-targeted hybrid hydrogels are expected to provide a platform for the next generation intelligent drug delivery systems.

Start-up of an anaerobic fluidized bed reactor treating synthetic carbohydrate rich wastewater.

PubMed

Yeshanew, Martha M; Frunzo, Luigi; Luongo, Vincenzo; Pirozzi, Francesco; Lens, Piet N L; Esposito, Giovanni

2016-12-15

The present work studied the start-up process of a mesophilic (37 ± 2 °C) anaerobic fluidized bed reactor (AFBR) operated at a hydraulic retention time (HRT) of 20 days using synthetic carbohydrate rich wastewater. Anox Kaldness-K1 carriers were used as biofilm carrier material. The reactor performance and biofilm formation were evaluated during the process. The start-up process at lower liquid recirculation flow rate enhanced the biofilm formation and reactor performance. The organic substrate composition had a major impact on early colonization of methanogenic archaea onto the surface of the Kaldness carriers during the start-up process. Specific organic substrates favouring the growth of methanogenic archaea, such as acetate, are preferred in order to facilitate the subsequent biofilm formation and AFBR start-up. The supply of 'bio-available' nutrients and trace elements, in particular iron, had an important role on optimal methanogenic activity and speeding-up of the biofilm development on the Kaldness carriers. This paper provides possible strategies to optimize the various operational parameters that influence the initial biofilm formation and development in an AFBR and similar high rate anaerobic reactors, hence can be used to reduce the long time required for process start-up. Copyright © 2016 Elsevier Ltd. All rights reserved.

Drug Delivery Systems, CNS Protection, and the Blood Brain Barrier

PubMed Central

Upadhyay, Ravi Kant

2014-01-01

Present review highlights various drug delivery systems used for delivery of pharmaceutical agents mainly antibiotics, antineoplastic agents, neuropeptides, and other therapeutic substances through the endothelial capillaries (BBB) for CNS therapeutics. In addition, the use of ultrasound in delivery of therapeutic agents/biomolecules such as proline rich peptides, prodrugs, radiopharmaceuticals, proteins, immunoglobulins, and chimeric peptides to the target sites in deep tissue locations inside tumor sites of brain has been explained. In addition, therapeutic applications of various types of nanoparticles such as chitosan based nanomers, dendrimers, carbon nanotubes, niosomes, beta cyclodextrin carriers, cholesterol mediated cationic solid lipid nanoparticles, colloidal drug carriers, liposomes, and micelles have been discussed with their recent advancements. Emphasis has been given on the need of physiological and therapeutic optimization of existing drug delivery methods and their carriers to deliver therapeutic amount of drug into the brain for treatment of various neurological diseases and disorders. Further, strong recommendations are being made to develop nanosized drug carriers/vehicles and noninvasive therapeutic alternatives of conventional methods for better therapeutics of CNS related diseases. Hence, there is an urgent need to design nontoxic biocompatible drugs and develop noninvasive delivery methods to check posttreatment clinical fatalities in neuropatients which occur due to existing highly toxic invasive drugs and treatment methods. PMID:25136634

Organized polysaccharide fibers as stable drug carriers

PubMed Central

Janaswamy, Srinivas; Gill, Kristin L.; Campanella, Osvaldo H.; Pinal, Rodolfo

2013-01-01

Many challenges arise during the development of new drug carrier systems, and paramount among them are safety, solubility and controlled release requirements. Although synthetic polymers are effective, the possibility of side effects imposes restrictions on their acceptable use and dose limits. Thus, a new drug carrier system that is safe to handle and free from side effects is very much in need and food grade polysaccharides stand tall as worthy alternatives. Herein, we demonstrate for the first time the feasibility of sodium iota-carrageenan fibers and their distinctive water pockets to embed and release a wide variety of drug molecules. Structural analysis has revealed the existence of crystalline network in the fibers even after encapsulating the drug molecules, and iota-carrageenan maintains its characteristic and reproducible double helical structure suggesting that the composites thus produced are reminiscent of cocrystals. The melting properties of iota-carrageenan:drug complexes are distinctly different from those of either drug or iota-carrageenan fiber. The encapsulated drugs are released in a sustained manner from the fiber matrix. Overall, our research provides an elegant opportunity for developing effective drug carriers with stable network toward enhancing and/or controlling bioavailability and extending shelf-life of drug molecules using GRAS excipients, food polysaccharides, that are inexpensive and non–toxic. PMID:23544530

Genome-Wide Association Study in BRCA1 Mutation Carriers Identifies Novel Loci Associated with Breast and Ovarian Cancer Risk

PubMed Central

Wang, Xianshu; McGuffog, Lesley; Lee, Andrew; Olswold, Curtis; Kuchenbaecker, Karoline B.; Soucy, Penny; Fredericksen, Zachary; Barrowdale, Daniel; Dennis, Joe; Gaudet, Mia M.; Dicks, Ed; Kosel, Matthew; Healey, Sue; Sinilnikova, Olga M.; Lee, Adam; Bacot, François; Vincent, Daniel; Hogervorst, Frans B. L.; Peock, Susan; Stoppa-Lyonnet, Dominique; Jakubowska, Anna; Investigators, kConFab; Radice, Paolo; Schmutzler, Rita Katharina; Domchek, Susan M.; Piedmonte, Marion; Singer, Christian F.; Friedman, Eitan; Thomassen, Mads; Hansen, Thomas V. O.; Neuhausen, Susan L.; Szabo, Csilla I.; Blanco, Ignacio; Greene, Mark H.; Karlan, Beth Y.; Garber, Judy; Phelan, Catherine M.; Weitzel, Jeffrey N.; Montagna, Marco; Olah, Edith; Andrulis, Irene L.; Godwin, Andrew K.; Yannoukakos, Drakoulis; Goldgar, David E.; Caldes, Trinidad; Nevanlinna, Heli; Osorio, Ana; Terry, Mary Beth; Daly, Mary B.; van Rensburg, Elizabeth J.; Hamann, Ute; Ramus, Susan J.; Ewart Toland, Amanda; Caligo, Maria A.; Olopade, Olufunmilayo I.; Tung, Nadine; Claes, Kathleen; Beattie, Mary S.; Southey, Melissa C.; Imyanitov, Evgeny N.; Tischkowitz, Marc; Janavicius, Ramunas; John, Esther M.; Kwong, Ava; Diez, Orland; Balmaña, Judith; Barkardottir, Rosa B.; Arun, Banu K.; Rennert, Gad; Teo, Soo-Hwang; Ganz, Patricia A.; Campbell, Ian; van der Hout, Annemarie H.; van Deurzen, Carolien H. M.; Seynaeve, Caroline; Gómez Garcia, Encarna B.; van Leeuwen, Flora E.; Meijers-Heijboer, Hanne E. J.; Gille, Johannes J. P.; Ausems, Margreet G. E. M.; Blok, Marinus J.; Ligtenberg, Marjolijn J. L.; Rookus, Matti A.; Devilee, Peter; Verhoef, Senno; van Os, Theo A. M.; Wijnen, Juul T.; Frost, Debra; Ellis, Steve; Fineberg, Elena; Platte, Radka; Evans, D. Gareth; Izatt, Louise; Eeles, Rosalind A.; Adlard, Julian; Eccles, Diana M.; Cook, Jackie; Brewer, Carole; Douglas, Fiona; Hodgson, Shirley; Morrison, Patrick J.; Side, Lucy E.; Donaldson, Alan; Houghton, Catherine; Rogers, Mark T.; Dorkins, Huw; Eason, Jacqueline; Gregory, Helen; McCann, Emma; Murray, Alex; Calender, Alain; Hardouin, Agnès; Berthet, Pascaline; Delnatte, Capucine; Nogues, Catherine; Lasset, Christine; Houdayer, Claude; Leroux, Dominique; Rouleau, Etienne; Prieur, Fabienne; Damiola, Francesca; Sobol, Hagay; Coupier, Isabelle; Venat-Bouvet, Laurence; Castera, Laurent; Gauthier-Villars, Marion; Léoné, Mélanie; Pujol, Pascal; Mazoyer, Sylvie; Bignon, Yves-Jean; Złowocka-Perłowska, Elżbieta; Gronwald, Jacek; Lubinski, Jan; Durda, Katarzyna; Jaworska, Katarzyna; Huzarski, Tomasz; Spurdle, Amanda B.; Viel, Alessandra; Peissel, Bernard; Bonanni, Bernardo; Melloni, Giulia; Ottini, Laura; Papi, Laura; Varesco, Liliana; Tibiletti, Maria Grazia; Peterlongo, Paolo; Volorio, Sara; Manoukian, Siranoush; Pensotti, Valeria; Arnold, Norbert; Engel, Christoph; Deissler, Helmut; Gadzicki, Dorothea; Gehrig, Andrea; Kast, Karin; Rhiem, Kerstin; Meindl, Alfons; Niederacher, Dieter; Ditsch, Nina; Plendl, Hansjoerg; Preisler-Adams, Sabine; Engert, Stefanie; Sutter, Christian; Varon-Mateeva, Raymonda; Wappenschmidt, Barbara; Weber, Bernhard H. F.; Arver, Brita; Stenmark-Askmalm, Marie; Loman, Niklas; Rosenquist, Richard; Einbeigi, Zakaria; Nathanson, Katherine L.; Rebbeck, Timothy R.; Blank, Stephanie V.; Cohn, David E.; Rodriguez, Gustavo C.; Small, Laurie; Friedlander, Michael; Bae-Jump, Victoria L.; Fink-Retter, Anneliese; Rappaport, Christine; Gschwantler-Kaulich, Daphne; Pfeiler, Georg; Tea, Muy-Kheng; Lindor, Noralane M.; Kaufman, Bella; Shimon Paluch, Shani; Laitman, Yael; Skytte, Anne-Bine; Gerdes, Anne-Marie; Pedersen, Inge Sokilde; Moeller, Sanne Traasdahl; Kruse, Torben A.; Jensen, Uffe Birk; Vijai, Joseph; Sarrel, Kara; Robson, Mark; Kauff, Noah; Mulligan, Anna Marie; Glendon, Gord; Ozcelik, Hilmi; Ejlertsen, Bent; Nielsen, Finn C.; Jønson, Lars; Andersen, Mette K.; Ding, Yuan Chun; Steele, Linda; Foretova, Lenka; Teulé, Alex; Lazaro, Conxi; Brunet, Joan; Pujana, Miquel Angel; Mai, Phuong L.; Loud, Jennifer T.; Walsh, Christine; Lester, Jenny; Orsulic, Sandra; Narod, Steven A.; Herzog, Josef; Sand, Sharon R.; Tognazzo, Silvia; Agata, Simona; Vaszko, Tibor; Weaver, Joellen; Stavropoulou, Alexandra V.; Buys, Saundra S.; Romero, Atocha; de la Hoya, Miguel; Aittomäki, Kristiina; Muranen, Taru A.; Duran, Mercedes; Chung, Wendy K.; Lasa, Adriana; Dorfling, Cecilia M.; Miron, Alexander; Benitez, Javier; Senter, Leigha; Huo, Dezheng; Chan, Salina B.; Sokolenko, Anna P.; Chiquette, Jocelyne; Tihomirova, Laima; Friebel, Tara M.; Agnarsson, Bjarni A.; Lu, Karen H.; Lejbkowicz, Flavio; James, Paul A.; Hall, Per; Dunning, Alison M.; Tessier, Daniel; Cunningham, Julie; Slager, Susan L.; Wang, Chen; Hart, Steven; Stevens, Kristen; Simard, Jacques; Pastinen, Tomi; Pankratz, Vernon S.; Offit, Kenneth; Antoniou, Antonis C.

2013-01-01

BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7×10−8, HR = 1.14, 95% CI: 1.09–1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4×10−8, HR = 1.27, 95% CI: 1.17–1.38) and 4q32.3 (rs4691139, P = 3.4×10−8, HR = 1.20, 95% CI: 1.17–1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific association. The 17q21.31 locus was also associated with ovarian cancer risk in 8,211 BRCA2 carriers (P = 2×10−4). These loci may lead to an improved understanding of the etiology of breast and ovarian tumors in BRCA1 carriers. Based on the joint distribution of the known BRCA1 breast cancer risk-modifying loci, we estimated that the breast cancer lifetime risks for the 5% of BRCA1 carriers at lowest risk are 28%–50% compared to 81%–100% for the 5% at highest risk. Similarly, based on the known ovarian cancer risk-modifying loci, the 5% of BRCA1 carriers at lowest risk have an estimated lifetime risk of developing ovarian cancer of 28% or lower, whereas the 5% at highest risk will have a risk of 63% or higher. Such differences in risk may have important implications for risk prediction and clinical management for BRCA1 carriers. PMID:23544013

Outcomes of an International Workshop on Preconception Expanded Carrier Screening: Some Considerations for Governments.

PubMed

Molster, Caron M; Lister, Karla; Metternick-Jones, Selina; Baynam, Gareth; Clarke, Angus John; Straub, Volker; Dawkins, Hugh J S; Laing, Nigel

2017-01-01

Consideration of expanded carrier screening has become an emerging issue for governments. However, traditional criteria for decision-making regarding screening programs do not incorporate all the issues relevant to expanded carrier screening. Further, there is a lack of consistent guidance in the literature regarding the development of appropriate criteria for government assessment of expanded carrier screening. Given this, a workshop was held to identify key public policy issues related to preconception expanded carrier screening, which governments should consider when deciding whether to publicly fund such programs. In June 2015, a satellite workshop was held at the European Society of Human Genetics Conference. It was structured around two design features: (1) the provision of information from a range of perspectives and (2) small group deliberations on the key issues that governments need to consider and the benefits, risks, and challenges of implementing publicly funded whole-population preconception carrier screening. Forty-one international experts attended the workshop. The deliberations centered primarily on the conditions to be tested and the elements of the screening program itself. Participants expected only severe conditions to be screened but were concerned about the lack of a consensus definition of "severe." Issues raised regarding the screening program included the purpose, benefits, harms, target population, program acceptability, components of a program, and economic evaluation. Participants also made arguments for consideration of the accuracy of screening tests. A wide range of issues require careful consideration by governments that want to assess expanded carrier screening. Traditional criteria for government decision-making regarding screening programs are not a "best fit" for expanded carrier screening and new models of decision-making with appropriate criteria are required. There is a need to define what a "severe" condition is, to build evidence regarding the reliability and accuracy of screening tests, to consider the equitable availability and downstream effects on and costs of follow-up interventions for those identified as carriers, and to explore the ways in which the components of a screening program would be impacted by unique features of expanded carrier screening.

Empirically based device modeling of bulk heterojunction organic photovoltaics

NASA Astrophysics Data System (ADS)

Pierre, Adrien; Lu, Shaofeng; Howard, Ian A.; Facchetti, Antonio; Arias, Ana Claudia

2013-04-01

We develop an empirically based optoelectronic model to accurately simulate the photocurrent in organic photovoltaic (OPV) devices with novel materials including bulk heterojunction OPV devices based on a new low band gap dithienothiophene-DPP donor polymer, P(TBT-DPP), blended with PC70BM at various donor-acceptor weight ratios and solvent compositions. Our devices exhibit power conversion efficiencies ranging from 1.8% to 4.7% at AM 1.5G. Electron and hole mobilities are determined using space-charge limited current measurements. Bimolecular recombination coefficients are both analytically calculated using slowest-carrier limited Langevin recombination and measured using an electro-optical pump-probe technique. Exciton quenching efficiencies in the donor and acceptor domains are determined from photoluminescence spectroscopy. In addition, dielectric and optical constants are experimentally determined. The photocurrent and its bias-dependence that we simulate using the optoelectronic model we develop, which takes into account these physically measured parameters, shows less than 7% error with respect to the experimental photocurrent (when both experimentally and semi-analytically determined recombination coefficient is used). Free carrier generation and recombination rates of the photocurrent are modeled as a function of the position in the active layer at various applied biases. These results show that while free carrier generation is maximized in the center of the device, free carrier recombination is most dominant near the electrodes even in high performance devices. Such knowledge of carrier activity is essential for the optimization of the active layer by enhancing light trapping and minimizing recombination. Our simulation program is intended to be freely distributed for use in laboratories fabricating OPV devices.

Quantitative analysis of SMN1 gene and estimation of SMN1 deletion carrier frequency in Korean population based on real-time PCR.

PubMed

Lee, Tae-Mi; Kim, Sang-Wun; Lee, Kwang-Soo; Jin, Hyun-Seok; Koo, Soo Kyung; Jo, Inho; Kang, Seongman; Jung, Sung-Chul

2004-12-01

Spinal muscular atrophy (SMA) is an autosomal recessive disorder, caused by homozygous absence of the survival motor neuron gene (SMN1) in approximately 94% of patients. Since most carriers have only one SMN1 gene copy, several SMN1 quantitative analyses have been used for the SMA carrier detection. We developed a reliable quantitative real-time PCR with SYBR Green I dye and studied 13 patients with SMA and their 24 parents, as well as 326 healthy normal individuals. The copy number of the SMN1 gene was determined by the comparative threshold cycle (Ct) method and albumin was used as a reference gene. The homozygous SMN1 deletion ratio of patients was 0.00 and the hemizygous SMN1 deletion ratio of parents ranged from 0.39 to 0.59. The deltadelta Ct ratios of 7 persons among 326 normal individuals were within the carrier range, 0.41-0.57. According to these data, we estimated the carrier and disease prevalence of SMA at 1/47 and 1/8,496 in Korean population, respectively. These data indicated that there would be no much difference in disease prevalence of SMA compared with western countries. Since the prevalence of SMA is higher than other autosomal recessive disorders, the carrier detection method using real-time PCR could be a useful tool for genetic counseling.

The design of two-stage-to-orbit vehicles

NASA Technical Reports Server (NTRS)

1991-01-01

Two separate student design groups developed conceptual designs for a two-stage-to-orbit vehicle, with each design group consisting of a carrier team and an orbiter team. A two-stage-to-orbit system is considered in the event that single-stage-to-orbit is deemed not feasible in the foreseeable future; the two-stage system would also be used as a complement to an already existing heavy lift vehicle. The design specifications given are to lift a 10,000-lb payload 27 ft long by 10 ft diameter, to low Earth orbit (300 n.m.) using an air breathing carrier configuration that will take off horizontally within 15,000 ft. The staging Mach number and altitude were to be determined by the design groups. One group designed a delta wing/body carrier with the orbiter nested within the fuselage of the carrier, and the other group produced a blended cranked-delta wing/body carrier with the orbiter in the more conventional piggyback configuration. Each carrier used liquid hydrogen-fueled turbofanramjet engines, with data provided by General Electric Aircraft Engine Group. While one orbiter used a full-scale Space Shuttle Main Engine (SSME), the other orbiter employed a half-scale SSME coupled with scramjet engines, with data again provided by General Electric. The two groups conceptual designs, along with the technical trade-offs, difficulties, and details that surfaced during the design process are presented.

Avian cholera in waterfowl: the role of lesser snow and Ross's geese as carriers of avian cholera in the Playa Lakes region

USGS Publications Warehouse

Samuel, M.D.; Shadduck, D.J.; Goldberg, Diana R.; Johnson, W.P.

2005-01-01

We collected samples from apparently healthy geese in the Playa Lakes Region (USA) during the winters of 2000a??01 and 2001a??02 to determine whether carriers of Pasteurella multocida, the bacterium that causes avian cholera, were present in wild populations. With the use of methods developed in laboratory challenge trials (Samuel et al., 2003a) and a serotype-specific polymerase chain reaction method for identification of P. multocida serotype 1, we found that a small proportion of 322 wild birds (<5%) were carriers of pathogenic P. multocida. On the basis of serology, an additional group of these birds (<10%) were survivors of recent avian cholera infection. Our results confirm the hypothesis that wild waterfowl are carriers of avian cholera and add support for the hypothesis that wild birds are a reservoir for this disease. In concert with other research, this work indicates that enzootic infection with avian cholera occurs in lesser snow goose (Chen caerulescens caerulescens) populations throughout their annual cycle. Although fewer Rossa??s geese (Chen rossii) were sampled, we also found these birds were carriers of P. multocida. Even in the absence of disease outbreaks, serologic evidence indicates that chronic disease transmission and recent infection are apparently occurring year-round in these highly gregarious birds and that a small portion of these populations are potential carriers with active infection.

Prevalence of precore-defective mutant of hepatitis B virus in HBV carriers.

PubMed

Niitsuma, H; Ishii, M; Saito, Y; Miura, M; Kobayashi, K; Ohori, H; Toyota, T

1995-08-01

Two hundred and seventy-three serum specimens from hepatitis B virus (HBV) carriers were examined for the presence of a characteristic one point mutation at nucleotide (nt) 1896 from the EcoRI site of the HBV genome in the precore region (the preC mutant) using restriction fragment length polymorphism (RFLP) analysis. This assay approach could detect preC mutants or wild-type sequences when either form constituted more than 10% of the total sample. Overall, 65.5% (76/116) of HBeAg-positive carriers had only the preC wild-type. All HBeAg-positive asymptomatic carriers (n = 14) had only the preC wild-type. In patients with chronic hepatitis B and in anti-HBe-positive asymptomatic carriers, increased prevalence of the preC mutant was associated with the development of anti-HBe antibodies and normalization of the serum alanine aminotransferase concentration. Furthermore, 27 (29.0%) of 93 HBeAg-negative carriers had unexpectedly preC wild-type sequences only. Direct sequencing of the HBV precore region of HBV specimens from 24 patients revealed no mutation at nt 1896, supporting the specificity of the RFLP analysis. These results suggest that RFLP analysis was accurate for the detection of the preC mutation and that the absence of serum HBeAg cannot be explained solely by the dominance of the preC mutant.

Polymeric behavior evaluation of PVP K30-poloxamer binary carrier for solid dispersed nisoldipine by experimental design.

PubMed

Kyaw Oo, May; Mandal, Uttam K; Chatterjee, Bappaditya

2017-02-01

High melting point polymeric carrier without plasticizer is unacceptable for solid dispersion (SD) by melting method. Combined polymer-plasticizer carrier significantly affects drug solubility and tableting property of SD. To evaluate and optimize the combined effect of a binary carrier consisting PVP K30 and poloxamer 188, on nisoldipine solubility and tensile strength of amorphous SD compact (SD compact ) by experimental design. SD of nisoldpine (SD nisol ) was prepared by melt mixing with different PVP K30 and poloxamer amount. A 3 2 factorial design was employed using nisoldipine solubility and tensile strength of SD compact as response variables. Statistical optimization by design expert software, and SD nisol characterization using ATR FTIR, DSC and microscopy were done. PVP K30:poloxamer, at a ratio of 3.73:6.63, was selected as the optimized combination of binary polymeric carrier resulting nisoldipine solubility of 115 μg/mL and tensile strength of 1.19 N/m 2 . PVP K30 had significant positive effect on both responses. Increase in poloxamer concentration after a certain level decreased nisoldipine solubility and tensile strength of SD compact . An optimized PVP K30-poloxamer binary composition for SD carrier was developed. Tensile strength of SD compact can be considered as a response for experimental design to optimize SD.

Influence of Pre-Freezing Temperature on the Corneal Endothelial Cytocompatibility and Cell Delivery Performance of Porous Hyaluronic Acid Hydrogel Carriers.

PubMed

Lai, Jui-Yang

2015-08-11

The development of porous hyaluronic acid (HA) hydrogels for corneal endothelial tissue engineering is attractive because they can be used as functional cell delivery carriers to help in the reconstruction of damaged areas. The purpose of this study was to investigate the corneal endothelial cytocompatibility and cell delivery performance of porous HA hydrogel biomaterials fabricated at different pre-freezing temperatures. As compared to their counterparts prepared at -80 °C, the HA samples fabricated at higher pre-freezing temperature (i.e., 0 °C) exhibited a larger pore size and higher porosity, thereby leading to lower resistance to glucose permeation. Live/dead assays and gene expression analyses showed that the restricted porous structure of HA carriers decreases the viability and ionic pump function of cultured corneal endothelial cells (CECs). The results also indicated that the porous hydrogel biomaterials fabricated at high pre-freezing temperature seem to be more compatible with rabbit CECs. In an animal model of corneal endothelial dysfunction, the wounded rabbit corneas receiving bioengineered CEC sheets and restricted porous-structured HA carriers demonstrated poor tissue reconstruction. The therapeutic efficacy of cell sheet transplants can be improved by using carrier materials prepared at high pre-freezing temperature. Our findings suggest that the cryogenic operation temperature-mediated pore microstructure of HA carriers plays an important role in corneal endothelial cytocompatibility and cell delivery performance.

Comparison of CRM197, diphtheria toxoid and tetanus toxoid as protein carriers for meningococcal glycoconjugate vaccines.

PubMed

Tontini, M; Berti, F; Romano, M R; Proietti, D; Zambonelli, C; Bottomley, M J; De Gregorio, E; Del Giudice, G; Rappuoli, R; Costantino, P; Brogioni, G; Balocchi, C; Biancucci, M; Malito, E

2013-10-01

Glycoconjugate vaccines are among the most effective and safest vaccines ever developed. Diphtheria toxoid (DT), tetanus toxoid (TT) and CRM197 have been mostly used as protein carriers in licensed vaccines. We evaluated the immunogenicity of serogroup A, C, W-135 and Y meningococcal oligosaccharides conjugated to CRM197, DT and TT in naïve mice. The three carriers were equally efficient in inducing an immune response against the carbohydrate moiety in immunologically naïve mice. The effect of previous exposure to different dosages of the carrier protein on the anti-carbohydrate response was studied using serogroup A meningococcal (MenA) saccharide conjugates as a model. CRM197 showed a strong propensity to positively prime the anti-carbohydrate response elicited by its conjugates or those with the antigenically related carrier DT. Conversely in any of the tested conditions TT priming did not result in enhancement of the anti-carbohydrate response elicited by the corresponding conjugates. Repeated exposure of mice to TT or to CRM197 before immunization with the respective MenA conjugates resulted in a drastic suppression of the anti-carbohydrate response in the case of TT conjugate and only in a slight reduction in the case of CRM197. The effect of carrier priming on the anti-MenA response of DT-based conjugates varied depending on their carbohydrate to protein ratio. These data may have implications for human vaccination since conjugate vaccines are widely used in individuals previously immunized with DT and TT carrier proteins. Copyright © 2013 Elsevier Ltd. All rights reserved.

Research on an uplink carrier sense multiple access algorithm of large indoor visible light communication networks based on an optical hard core point process.

PubMed

Nan, Zhufen; Chi, Xuefen

2016-12-20

The IEEE 802.15.7 protocol suggests that it could coordinate the channel access process based on the competitive method of carrier sensing. However, the directionality of light and randomness of diffuse reflection would give rise to a serious imperfect carrier sense (ICS) problem [e.g., hidden node (HN) problem and exposed node (EN) problem], which brings great challenges in realizing the optical carrier sense multiple access (CSMA) mechanism. In this paper, the carrier sense process implemented by diffuse reflection light is modeled as the choice of independent sets. We establish an ICS model with the presence of ENs and HNs for the multi-point to multi-point visible light communication (VLC) uplink communications system. Considering the severe optical ICS problem, an optical hard core point process (OHCPP) is developed, which characterizes the optical CSMA for the indoor VLC uplink communications system. Due to the limited coverage of the transmitted optical signal, in our OHCPP, the ENs within the transmitters' carrier sense region could be retained provided that they could not corrupt the ongoing communications. Moreover, because of the directionality of both light emitting diode (LED) transmitters and receivers, theoretical analysis of the HN problem becomes difficult. In this paper, we derive the closed-form expression for approximating the outage probability and transmission capacity of VLC networks with the presence of HNs and ENs. Simulation results validate the analysis and also show the existence of an optimal physical carrier-sensing threshold that maximizes the transmission capacity for a given emission angle of LED.

Coencapsulation of oxygen carriers and glucose oxidase in polyelectrolyte complex capsules for the enhancement of D-gluconic acid and delta-gluconolactone production.

PubMed

Bucko, Marek; Gemeiner, Peter; Vikartovská, Alica; Mislovicová, Danica; Lacík, Igor; Tkác, Ján

2010-04-01

A novel encapsulated oxidative biocatalyst comprising glucose oxidase (GOD) coencapsulated with oxygen carriers within polyelectrolyte complex capsules was developed for the production of D-gluconic acid and delta-gluconolactone. The capsules containing immobilized GOD were produced by polyelectrolyte complexation with sodium alginate (SA) and cellulose sulfate (CS) as polyanions, poly(methylene-co-guanidine) (PMCG) as the polycation, CaCl(2) as the gelling agent and NaCl as the antigelling agent (GOD-SA-CS/PMCG capsules). Poly(dimethylsiloxane) (PDMS) and an emulsion of n-dodecane (DOD) or perfluorodecaline (PFD) with PDMS were used as the oxygen carriers and MnO(2) was used as a hydrogen peroxide decomposition catalyst. Water-soluble PDMS was found to act as both an oxygen carrier and an emulsifier of water-insoluble DOD and PFD. Stable microcapsules could be produced with concentrations of up to 4% (w/w) of PDMS, 10% (w/w) of DOD and PFD, and 25% (w/w) of MnO(2) in the polyanion solution of SA and CS. Roughly a two-fold increase in the GOD activity from 21.0+/-1.1 to 38.4+/-2.0 U*g(-1) and product space-time yields (STY) from 44.3+/-2.0 to 83.4+/-3.4 g*H*day(-1) could be achieved utilizing coencapsulated oxygen carriers compared to GOD encapsulated in the absence of oxygen carriers. This enhanced production does not significantly depend on the selected oxygen carrier under the conditions used in this study.

Common alleles at 6q25.1 and 1p11.2 are associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers

PubMed Central

Antoniou, Antonis C; Kartsonaki, Christiana; Sinilnikova, Olga M.; Soucy, Penny; McGuffog, Lesley; Healey, Sue; Lee, Andrew; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Cattaneo, Elisa; Barile, Monica; Pensotti, Valeria; Pasini, Barbara; Dolcetti, Riccardo; Giannini, Giuseppe; Laura Putignano, Anna; Varesco, Liliana; Radice, Paolo; Mai, Phuong L.; Greene, Mark H.; Andrulis, Irene L.; Glendon, Gord; Ozcelik, Hilmi; Thomassen, Mads; Gerdes, Anne-Marie; Kruse, Torben A.; Birk Jensen, Uffe; Crüger, Dorthe G.; Caligo, Maria A.; Laitman, Yael; Milgrom, Roni; Kaufman, Bella; Paluch-Shimon, Shani; Friedman, Eitan; Loman, Niklas; Harbst, Katja; Lindblom, Annika; Arver, Brita; Ehrencrona, Hans; Melin, Beatrice; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy; Jakubowska, Ania; Lubinski, Jan; Gronwald, Jacek; Huzarski, Tomasz; Byrski, Tomasz; Cybulski, Cezary; Gorski, Bohdan; Osorio, Ana; Ramón y Cajal, Teresa; Fostira, Florentia; Andrés, Raquel; Benitez, Javier; Hamann, Ute; Hogervorst, Frans B.; Rookus, Matti A.; Hooning, Maartje J.; Nelen, Marcel R.; van der Luijt, Rob B.; van Os, Theo A.M.; van Asperen, Christi J.; Devilee, Peter; Meijers-Heijboer, Hanne E.J.; Gómez Garcia, Encarna B.; Peock, Susan; Cook, Margaret; Frost, Debra; Platte, Radka; Leyland, Jean; Gareth Evans, D.; Lalloo, Fiona; Eeles, Ros; Izatt, Louise; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana; Ong, Kai-ren; Cook, Jackie; Douglas, Fiona; Paterson, Joan; John Kennedy, M.; Miedzybrodzka, Zosia; Godwin, Andrew; Stoppa-Lyonnet, Dominique; Buecher, Bruno; Belotti, Muriel; Tirapo, Carole; Mazoyer, Sylvie; Barjhoux, Laure; Lasset, Christine; Leroux, Dominique; Faivre, Laurence; Bronner, Myriam; Prieur, Fabienne; Nogues, Catherine; Rouleau, Etienne; Pujol, Pascal; Coupier, Isabelle; Frénay, Marc; Hopper, John L.; Daly, Mary B.; Terry, Mary B.; John, Esther M.; Buys, Saundra S.; Yassin, Yosuf; Miron, Alexander; Goldgar, David; Singer, Christian F.; Tea, Muy-Kheng; Pfeiler, Georg; Catharina Dressler, Anne; Hansen, Thomas v.O.; Jønson, Lars; Ejlertsen, Bent; Bjork Barkardottir, Rosa; Kirchhoff, Tomas; Offit, Kenneth; Piedmonte, Marion; Rodriguez, Gustavo; Small, Laurie; Boggess, John; Blank, Stephanie; Basil, Jack; Azodi, Masoud; Ewart Toland, Amanda; Montagna, Marco; Tognazzo, Silvia; Agata, Simona; Imyanitov, Evgeny; Janavicius, Ramunas; Lazaro, Conxi; Blanco, Ignacio; Pharoah, Paul D.P.; Sucheston, Lara; Karlan, Beth Y.; Walsh, Christine S.; Olah, Edith; Bozsik, Aniko; Teo, Soo-Hwang; Seldon, Joyce L.; Beattie, Mary S.; van Rensburg, Elizabeth J.; Sluiter, Michelle D.; Diez, Orland; Schmutzler, Rita K.; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ruehl, Ina; Varon-Mateeva, Raymonda; Kast, Karin; Deissler, Helmut; Niederacher, Dieter; Arnold, Norbert; Gadzicki, Dorothea; Schönbuchner, Ines; Caldes, Trinidad; de la Hoya, Miguel; Nevanlinna, Heli; Aittomäki, Kristiina; Dumont, Martine; Chiquette, Jocelyne; Tischkowitz, Marc; Chen, Xiaoqing; Beesley, Jonathan; Spurdle, Amanda B.; Neuhausen, Susan L.; Chun Ding, Yuan; Fredericksen, Zachary; Wang, Xianshu; Pankratz, Vernon S.; Couch, Fergus; Simard, Jacques; Easton, Douglas F.; Chenevix-Trench, Georgia

2011-01-01

Two single nucleotide polymorphisms (SNPs) at 6q25.1, near the ESR1 gene, have been implicated in the susceptibility to breast cancer for Asian (rs2046210) and European women (rs9397435). A genome-wide association study in Europeans identified two further breast cancer susceptibility variants: rs11249433 at 1p11.2 and rs999737 in RAD51L1 at 14q24.1. Although previously identified breast cancer susceptibility variants have been shown to be associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers, the involvement of these SNPs to breast cancer susceptibility in mutation carriers is currently unknown. To address this, we genotyped these SNPs in BRCA1 and BRCA2 mutation carriers from 42 studies from the Consortium of Investigators of Modifiers of BRCA1/2. In the analysis of 14 123 BRCA1 and 8053 BRCA2 mutation carriers of European ancestry, the 6q25.1 SNPs (r2 = 0.14) were independently associated with the risk of breast cancer for BRCA1 mutation carriers [hazard ratio (HR) = 1.17, 95% confidence interval (CI): 1.11–1.23, P-trend = 4.5 × 10−9 for rs2046210; HR = 1.28, 95% CI: 1.18–1.40, P-trend = 1.3 × 10−8 for rs9397435], but only rs9397435 was associated with the risk for BRCA2 carriers (HR = 1.14, 95% CI: 1.01–1.28, P-trend = 0.031). SNP rs11249433 (1p11.2) was associated with the risk of breast cancer for BRCA2 mutation carriers (HR = 1.09, 95% CI: 1.02–1.17, P-trend = 0.015), but was not associated with breast cancer risk for BRCA1 mutation carriers (HR = 0.97, 95% CI: 0.92–1.02, P-trend = 0.20). SNP rs999737 (RAD51L1) was not associated with breast cancer risk for either BRCA1 or BRCA2 mutation carriers (P-trend = 0.27 and 0.30, respectively). The identification of SNPs at 6q25.1 associated with breast cancer risk for BRCA1 mutation carriers will lead to a better understanding of the biology of tumour development in these women. PMID:21593217

Common variants at the 19p13.1 and ZNF365 loci are associated with ER subtypes of breast cancer and ovarian cancer risk in BRCA1 and BRCA2 mutation carriers

PubMed Central

Couch, Fergus J.; Gaudet, Mia M.; Antoniou, Antonis C.; Ramus, Susan J.; Kuchenbaecker, Karoline B.; Soucy, Penny; Beesley, Jonathan; Chen, Xiaoqing; Wang, Xianshu; Kirchhoff, Tomas; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; Healey, Sue; Sinilnikova, Olga M.; Andrulis, Irene L.; Ozcelik, Hilmi; Mulligan, Anna Marie; Thomassen, Mads; Gerdes, Anne-Marie; Jensen, Uffe Birk; Skytte, Anne-Bine; Kruse, Torben A.; Caligo, Maria A.; von Wachenfeldt, Anna; Barbany-Bustinza, Gisela; Loman, Niklas; Soller, Maria; Ehrencrona, Hans; Karlsson, Per; Nathanson, Katherine L.; Rebbeck, Timothy R.; Domchek, Susan M.; Jakubowska, Ania; Lubinski, Jan; Jaworska, Katarzyna; Durda, Katarzyna; Złowocka, Elżbieta; Huzarski, Tomasz; Byrski, Tomasz; Gronwald, Jacek; Cybulski, Cezary; Górski, Bohdan; Osorio, Ana; Durán, Mercedes; Tejada, María Isabel; Benitez, Javier; Hamann, Ute; Hogervorst, Frans B.L.; van Os, Theo A.; van Leeuwen, Flora E.; Meijers-Heijboer, Hanne E.J.; Wijnen, Juul; Blok, Marinus J.; Kets, Marleen; Hooning, Maartje J.; Oldenburg, Rogier A.; Ausems, Margreet G.E.M.; Peock, Susan; Frost, Debra; Ellis, Steve D.; Platte, Radka; Fineberg, Elena; Evans, D. Gareth; Jacobs, Chris; Eeles, Rosalind A.; Adlard, Julian; Davidson, Rosemarie; Eccles, Diana M.; Cole, Trevor; Cook, Jackie; Paterson, Joan; Brewer, Carole; Douglas, Fiona; Hodgson, Shirley V.; Morrison, Patrick J.; Walker, Lisa; Porteous, Mary E.; Kennedy, M. John; Side, Lucy E.; Bove, Betsy; Godwin, Andrew K.; Stoppa-Lyonnet, Dominique; Fassy-Colcombet, Marion; Castera, Laurent; Cornelis, François; Mazoyer, Sylvie; Léoné, Mélanie; Boutry-Kryza, Nadia; Bressac-de Paillerets, Brigitte; Caron, Olivier; Pujol, Pascal; Coupier, Isabelle; Delnatte, Capucine; Akloul, Linda; Lynch, Henry T.; Snyder, Carrie L.; Buys, Saundra S.; Daly, Mary B.; Terry, MaryBeth; Chung, Wendy K.; John, Esther M.; Miron, Alexander; Southey, Melissa C.; Hopper, John L.; Goldgar, David E.; Singer, Christian F.; Rappaport, Christine; Tea, Muy-Kheng M.; Fink-Retter, Anneliese; Hansen, Thomas V. O.; Nielsen, Finn C.; Arason, Aðalgeir; Vijai, Joseph; Shah, Sohela; Sarrel, Kara; Robson, Mark E.; Piedmonte, Marion; Phillips, Kelly; Basil, Jack; Rubinstein, Wendy S.; Boggess, John; Wakeley, Katie; Ewart-Toland, Amanda; Montagna, Marco; Agata, Simona; Imyanitov, Evgeny N.; Isaacs, Claudine; Janavicius, Ramunas; Lazaro, Conxi; Blanco, Ignacio; Feliubadalo, Lidia; Brunet, Joan; Gayther, Simon A; Pharoah, Paul PD; Odunsi, Kunle O.; Karlan, Beth Y.; Walsh, Christine S.; Olah, Edith; Teo, Soo Hwang; Ganz, Patricia A.; Beattie, Mary S.; van Rensburg, Elizabeth J.; Dorfling, Cecelia M.; Diez, Orland; Kwong, Ava; Schmutzler, Rita K.; Wappenschmidt, Barbara; Engel, Christoph; Meindl, Alfons; Ditsch, Nina; Arnold, Norbert; Heidemann, Simone; Niederacher, Dieter; Preisler-Adams, Sabine; Gadzicki, Dorothea; Varon-Mateeva, Raymonda; Deissler, Helmut; Gehrig, Andrea; Sutter, Christian; Kast, Karin; Fiebig, Britta; Heinritz, Wolfram; Caldes, Trinidad; de la Hoya, Miguel; Muranen, Taru A.; Nevanlinna, Heli; Tischkowitz, Marc D.; Spurdle, Amanda B.; Neuhausen, Susan L.; Ding, Yuan Chun; Lindor, Noralane M.; Fredericksen, Zachary; Pankratz, V. Shane; Peterlongo, Paolo; Manoukian, Siranoush; Peissel, Bernard; Zaffaroni, Daniela; Barile, Monica; Bernard, Loris; Viel, Alessandra; Giannini, Giuseppe; Varesco, Liliana; Radice, Paolo; Greene, Mark H.; Mai, Phuong L.; Easton, Douglas F.; Chenevix-Trench, Georgia; Offit, Kenneth; Simard, Jacques

2012-01-01

Background Genome-wide association studies (GWAS) identified variants at 19p13.1 and ZNF365 (10q21.2) as risk factors for breast cancer among BRCA1 and BRCA2 mutation carriers, respectively. We explored associations with ovarian cancer and with breast cancer by tumor histopathology for these variants in mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Methods Genotyping data for 12,599 BRCA1 and 7,132 BRCA2 mutation carriers from 40 studies were combined. Results We confirmed associations between rs8170 at 19p13.1 and breast cancer risk for BRCA1 mutation carriers (hazard ratio (HR)=1.17; 95%CI 1.07–1.27; p=7.42×10−4) and between rs16917302 at ZNF365 (HR=0.84; 95%CI 0.73–0.97; p=0.017) but not rs311499 at 20q13.3 (HR=1.11; 95%CI 0.94–1.31; p=0.22) and breast cancer risk for BRCA2 mutation carriers. Analyses based on tumor histopathology showed that 19p13 variants were predominantly associated with estrogen receptor (ER)-negative breast cancer for both BRCA1 and BRCA2 mutation carriers, whereas rs16917302 at ZNF365 was mainly associated with ER-positive breast cancer for both BRCA1 and BRCA2 mutation carriers. We also found for the first time that rs67397200 at 19p13.1 was associated with an increased risk of ovarian cancer for BRCA1 (HR=1.16; 95%CI 1.05–1.29; p=3.8×10−4) and BRCA2 mutation carriers (HR=1.30; 95%CI 1.10–1.52; p=1.8×10−3). Conclusions 19p13.1 and ZNF365 are susceptibility loci for ovarian cancer and ER subtypes of breast cancer among BRCA1 and BRCA2 mutation carriers. Impact These findings can lead to an improved understanding of tumor development and may prove useful for breast and ovarian cancer risk prediction for BRCA1 and BRCA2 mutation carriers. PMID:22351618

Development of the Facet Cryostat

NASA Technical Reports Server (NTRS)

Nash, A.; Shields, P.; Jirmanus, M.

1999-01-01

A proof of concept prototype cryostat has been developed to demonstrate the ability to accommodate low temperature science investigations within the constraints of the Hitchhiker siderail carrier on the Space Shuttle.

European retrievable carrier (Eureca) and evolutionary space carrier for microgravity, Earth observation and technology demonstration

NASA Technical Reports Server (NTRS)

Mory, R.; Seibert, G.

1984-01-01

The Spacelab relatively short stay-time in orbit has led to consideration of the European Retrievable Carrier (EURECA) concept as a reusable carrier. The EURECA concept is a free-flying carrier of experiments which is launched and recovered by the space shuttle. It is commensurate with the size of payloads that can be economically developed in Europe and combines the advantages of Spacelab (high mass and power capability, recovery) with those of a free flyer (extended operating time in a non-polluted environment). The launch of the first EURECA mission is scheduled for October 1987. The Eureca spacecraft will be deployed from the Shuttle cargo bay in orbit, will operate in a free-flying mode for about six months, and will then be retrieved, together with its payloads, returned to Earth by the Space Shuttle and prepared for the next mission. The first mission of EURECA is dedicated to research in the fields of life sciences and material sciences. The experimental hardware of the first mission consist of a variety of processin chambers for crystal growth and equipment for biological investigations viz plant growth and protein crystallization, and there is the possibility to perform experiments in the field of exobiology.

APOE polymorphism as a potential determinant of functional fitness in the elderly regardless of nutritional status.

PubMed

Snejdrlova, Michaela; Kalvach, Zdenek; Topinkova, Eva; Vrablik, Michal; Prochazkova, Renata; Kvasilova, Marie; Lanska, Vera; Zlatohlavek, Lukas; Prusikova, Martina; Ceska, Richard

2011-01-01

Life expectancy is determined by a combination of genetic predisposition (~25%) and environmental influences (~75%). Nevertheless a stronger genetic influence is anticipated in long-living individuals. Apolipoprotein E (APOE) gene belongs among the most studied candidate genes of longevity. We evaluated the relation of APOE polymorphism and fitness status in the elderly. We examined a total number of 128 subjects, over 80 years of age. Using a battery of functional tests their fitness status was assessed and the subjects were stratified into 5 functional categories according to Spirduso´s classification. Biochemistry analysis was performed by enzymatic method using automated analyzers. APOE gene polymorphism was analysed performed using PCR-RFLP. APOE4 allele carriers had significantly worse fitness status compared to non-carriers (p=0.025). Multiple logistic regression analysis showed the APOE4 carriers had higher risk (p=0.05) of functional unfitness compared to APOE2/E3 individuals. APOE gene polymorphism seems be an important genetic contributor to frailty development in the elderly. While APOE2 carriers tend to remain functionally fit till higher age, the functional status of APOE4 carriers deteriorates more rapidly. © 2011 Neuroendocrinology Letters

Synthesis, characterization and in vitro cytotoxicity analysis of a novel cellulose based drug carrier for the controlled delivery of 5-fluorouracil, an anticancer drug

NASA Astrophysics Data System (ADS)

Anirudhan, Thayyath S.; Nima, Jayachandran; Divya, Peethambaran L.

2015-11-01

The present investigation concerns the development and evaluation of a novel drug delivery system, aminated-glycidylmethacrylate grafted cellulose-grafted polymethacrylic acid-succinyl cyclodextrin (Cell-g-(GMA/en)-PMA-SCD) for the controlled release of 5-Fluorouracil, an anticancer drug. The prepared drug carrier was characterized by FT-IR, XRD and SEM techniques. Binding kinetics and isotherm studies of 5-FU onto Cell-g-(GMA/en)-PMA-SCD were found to follow pseudo-second-order and Langmuir model respectively. Maximum binding capacity of drug carrier was found to be 149.09 mg g-1 at 37 °C. Swelling studies, in vitro release kinetics, drug loading efficiency and encapsulation efficiency of Cell-g-(GMA/en)-PMA-SCD were studied. The release kinetics was analyzed using Ritger-Peppas equation at pH 7.4. Cytotoxicity analysis on MCF-7 (human breast carcinoma) cells indicated that the drug carrier shows sustained and controlled release of drug to the target site. Hence, it is evident from this investigation that Cell-g-(GMA/en)-PMA-SCD could be a promising carrier for 5-FU.

Apolipoprotein E4 Allele and Gait Performance in Mild Cognitive Impairment: Results From the Gait and Brain Study.

PubMed

Sakurai, Ryota; Montero-Odasso, Manuel

2017-11-09

The apolipoprotein E polymorphism ε4 allele (ApoE4) and gait impairment are both known risk factors for developing cognitive decline and dementia. However, it is unclear the interrelationship between these factors, particularly among older adults with mild cognitive impairment (MCI) who are considered as prodromal for Alzheimer's disease. This study aimed to determine whether ApoE4 carrier individuals with MCI may experience greater impairment in gait performance. Fifty-six older adults with MCI from the "Gait and Brain Study" who were identified as either ApoE4 carriers (n = 20) or non-ApoE4 carriers (n = 36) with 1 year of follow-up were included. Gait variability, the main outcome variable, was assessed as stride time variability with an electronic walkway. Additional gait variables and cognitive performance (mini-mental state examination [MMSE] and Montreal Cognitive Assessment [MoCA]) were also recorded. Covariates included age, sex, education level, body mass index, and number of comorbidities. Baseline characteristics were similar for both groups. Repeated measures analysis of covariance showed that gait stride time and stride length variabilities significantly increased in ApoE4 carriers but was maintained in the non-ApoE4 carriers. Similarly, ApoE4 carriers showed greater decrease in MMSE score at follow-up. In this sample of older adults with MCI, the presence of at least one copy of ApoE4 was associated with the development of both increased gait variability and cognitive decline during 1 year of follow-up. ApoE4 genotype might be considered as a potential mediator of decline in mobility function in MCI; future studies with larger samples are needed to confirm our preliminary findings. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Standardized system for quantifying residual dirt on medical appliances cleansed in hospital washers--disinfectors: dirt detection by different methods.

PubMed

Sigler, K; Gásková, D; Chládková, K; Knebl, R; Wimmer, T; Vacata, V; Gebel, J

2003-01-01

An easy-to construct, easy-to-operate standardized system was developed for determining the residual biological contamination of surgical instruments, endoscopes and other medical appliances subjected to hospital cleansing and/or disinfection. It consists of standard-sized pieces of glass, metal or endoscope plastic--dirt carriers--either bare or enclosed in truncated Eppendorf caps to simulate hard-to-access conditions. The surface of the carriers is covered with model dirt simulating biological contamination and the carriers are then affixed to sturdy metal holders. Conventional model dirt were found to peel or flake off the carrier surface, lowering the precision of residual soil determination. A newly developed model dirt consisting of liver mash, lactose and sunflower oil and exhibiting low tendency to peel off surfaces was therefore used. The whole setup was subjected to chemical or enzymic cleansing programs at elevated temperature in hospital washer-disinfectors of two types, and the residual dirt after cleansing was determined by three methods. The method using toxicant-doped dirt that quenches the luminescence of an indicator bacterium Photobacterium phosphoreum gave satisfactory data under laboratory conditions but with hospital-washed samples it exhibited excessive fluctuations caused by bacterium--dirt interactions and by physical influences. Both other methods gave better results but displayed some process sensitivity. The luciferin-luciferase-based ATP bioluminescence assay sometimes gave low or even negative dirt level values and showed a low effect of reduced dirt accessibility on cleansing of metal carriers. The Bradford protein assay showed about equal cleansing efficiency for both easily and poorly accessible carriers after enzymic cleansing. Our system can be used for determining low levels of residual contamination of medical appliances after cleansing/disinfection and assessing the efficiency of commercial washer-disinfectors; its efficiency can be further increased by using a cleansing process-insensitive method for soil detection and quantification.

Rational Design of Mixed-Metal Oxides for Chemical Looping Combustion of Coal via Coupled Computational-Experimental Studies

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

Mishra, Amit; Li, Fanxing; Santiso, Erik

Energy and global climate change are two grand challenges to the modern society. An urgent need exists for development of clean and efficient energy conversion processes. The chemical looping strategy, which utilizes regenerable oxygen carriers (OCs) to indirectly convert carbonaceous fuels via redox reactions, is considered to be one of the more promising approaches for CO2 capture by the U.S. Department of Energy (USDOE). To date, most long-term chemical looping operations were conducted using gaseous fuels, even though direct conversion of coal is more desirable from both economics and CO2 capture viewpoints. The main challenges for direct coal conversion residemore » in the stringent requirements on oxygen carrier performances. In addition, coal char and volatile compounds are more challenging to convert than gaseous fuels. A promising approach for direct conversion of coal is the so called chemical looping with oxygen uncoupling (CLOU) technique. In the CLOU process, a metal oxide that decomposes at the looping temperature, and releases oxygen to the gas phase is used as the OC. The overarching objective of this project was to discover the fundamental principles for rational design and optimization of oxygen carriers (OC) in coal chemical looping combustion (CLC) processes. It directly addresses Topic Area B of the funding opportunity announcement (FOA) in terms of “predictive description of the phase behavior and mechanical properties” of “mixed metal oxide” based OCs and rational development of new OC materials with superior functionality. This was achieved through studies exploring i) iron-containing mixed-oxide composites as oxygen carriers for CLOU, ii) Ca1-xAxMnO3-δ (A = Sr and Ba) as oxygen carriers for CLOU, iii) CaMn1-xBxO3-δ (B=Al, V, Fe, Co, and Ni) as oxygen carrier for CLOU and iv) vacancy creation energy in Mn-containing perovskites as an indicator chemical looping with oxygen uncoupling.« less

Clinical progression and metachronous paragangliomas in a large cohort of SDHD germline variant carriers.

PubMed

Heesterman, Berdine L; de Pont, Lisa M H; van der Mey, Andel Gl; Bayley, Jean-Pierre; Corssmit, Eleonora Pm; Hes, Frederik J; Verbist, Berit M; van Benthem, Peter Paul G; Jansen, Jeroen C

2018-05-18

Although it is well established that paternally transmitted germline variants in SDHD are associated with multifocal paragangliomas and lifelong follow-up is generally advised, the risk of metachronous lesions is presently unknown. In a large Dutch cohort of SDHD variant carriers, we studied the development of new paragangliomas, and the evolution of symptoms and cranial nerve impairment. Recurrent event analysis and the Kaplan-Meier product limit estimator were used to study the risk of new lesions. The relation between several predictors and development of new symptoms was assessed using logistic regression. Of the 222 SDHD variant carriers included, 65% presented with symptoms and 11% with cranial nerve dysfunction. Over a median period of 8 years, 42% reported new symptoms, and new cranial nerve impairment was observed in 11% of subjects. The estimated fraction of subjects that developed new HNPGL increased to 73% (95% CI: 52-85%) after 22 years of follow-up. Males were more likely to develop new HNPGL compared to females (HR: 1.63, 95% CI: 1.10-2.40), as were subjects that presented with symptoms, compared to subjects that were asymptomatic at baseline (HR: 1.61, 95% CI: 1.01-2.55). In addition, the risk of new lesions decreased with number of HNPGL present at first diagnosis (HR: 0.68 and 95% CI: 0.56-0.82). Carriers of a paternally inherited SDHD variant face a considerable risk for new HNPGL. In addition, nearly 50% of subjects reported new symptoms. However, new cranial nerve deficits were observed in only 11%, which is less than reported in surgical series. These risks should be taken into account when considering treatment strategies and counseling.

Developing and establishing the validity and reliability of the perceptions toward Aviation Safety Action Program (ASAP) and Line Operations Safety Audit (LOSA) questionnaires

NASA Astrophysics Data System (ADS)

Steckel, Richard J.

Aviation Safety Action Program (ASAP) and Line Operations Safety Audits (LOSA) are voluntary safety reporting programs developed by the Federal Aviation Administration (FAA) to assist air carriers in discovering and fixing threats, errors and undesired aircraft states during normal flights that could result in a serious or fatal accident. These programs depend on voluntary participation of and reporting by air carrier pilots to be successful. The purpose of the study was to develop and validate a measurement scale to measure U.S. air carrier pilots' perceived benefits and/or barriers to participating in ASAP and LOSA programs. Data from these surveys could be used to make changes to or correct pilot misperceptions of these programs to improve participation and the flow of data. ASAP and LOSA a priori models were developed based on previous research in aviation and healthcare. Sixty thousand ASAP and LOSA paper surveys were sent to 60,000 current U.S. air carrier pilots selected at random from an FAA database of pilot certificates. Two thousand usable ASAP and 1,970 usable LOSA surveys were returned and analyzed using Confirmatory Factor Analysis. Analysis of the data using confirmatory actor analysis and model generation resulted in a five factor ASAP model (Ease of use, Value, Improve, Trust and Risk) and a five factor LOSA model (Value, Improve, Program Trust, Risk and Management Trust). ASAP and LOSA data were not normally distributed, so bootstrapping was used. While both final models exhibited acceptable fit with approximate fit indices, the exact fit hypothesis and the Bollen-Stine p value indicated possible model mis-specification for both ASAP and LOSA models.

HIV-1 vaccine strategies utilizing viral vectors including antigen- displayed inoviral vectors.

PubMed

Hassapis, Kyriakos A; Kostrikis, Leondios G

2013-12-01

Antigen-presenting viral vectors have been extensively used as vehicles for the presentation of antigens to the immune system in numerous vaccine strategies. Particularly in HIV vaccine development efforts, two main viral vectors have been used as antigen carriers: (a) live attenuated vectors and (b) virus-like particles (VLPs); the former, although highly effective in animal studies, cannot be clinically tested in humans due to safety concerns and the latter have failed to induce broadly neutralizing anti-HIV antibodies. For more than two decades, Inoviruses (non-lytic bacterial phages) have also been utilized as antigen carriers in several vaccine studies. Inoviral vectors are important antigen-carriers in vaccine development due to their ability to present an antigen on their outer architecture in many copies and to their natural high immunogenicity. Numerous fundamental studies have been conducted, which have established the unique properties of antigen-displayed inoviral vectors in HIV vaccine efforts. The recent isolation of new, potent anti-HIV broadly neutralizing monoclonal antibodies provides a new momentum in this emerging technology.

Genetically engineered nanocarriers for drug delivery.

PubMed

Shi, Pu; Gustafson, Joshua A; MacKay, J Andrew

2014-01-01

Cytotoxicity, low water solubility, rapid clearance from circulation, and off-target side-effects are common drawbacks of conventional small-molecule drugs. To overcome these shortcomings, many multifunctional nanocarriers have been proposed to enhance drug delivery. In concept, multifunctional nanoparticles might carry multiple agents, control release rate, biodegrade, and utilize target-mediated drug delivery; however, the design of these particles presents many challenges at the stage of pharmaceutical development. An emerging solution to improve control over these particles is to turn to genetic engineering. Genetically engineered nanocarriers are precisely controlled in size and structure and can provide specific control over sites for chemical attachment of drugs. Genetically engineered drug carriers that assemble nanostructures including nanoparticles and nanofibers can be polymeric or non-polymeric. This review summarizes the recent development of applications in drug and gene delivery utilizing nanostructures of polymeric genetically engineered drug carriers such as elastin-like polypeptides, silk-like polypeptides, and silk-elastin-like protein polymers, and non-polymeric genetically engineered drug carriers such as vault proteins and viral proteins.

Genetically engineered nanocarriers for drug delivery

PubMed Central

Shi, Pu; Gustafson, Joshua A; MacKay, J Andrew

2014-01-01

Cytotoxicity, low water solubility, rapid clearance from circulation, and off-target side-effects are common drawbacks of conventional small-molecule drugs. To overcome these shortcomings, many multifunctional nanocarriers have been proposed to enhance drug delivery. In concept, multifunctional nanoparticles might carry multiple agents, control release rate, biodegrade, and utilize target-mediated drug delivery; however, the design of these particles presents many challenges at the stage of pharmaceutical development. An emerging solution to improve control over these particles is to turn to genetic engineering. Genetically engineered nanocarriers are precisely controlled in size and structure and can provide specific control over sites for chemical attachment of drugs. Genetically engineered drug carriers that assemble nanostructures including nanoparticles and nanofibers can be polymeric or non-polymeric. This review summarizes the recent development of applications in drug and gene delivery utilizing nanostructures of polymeric genetically engineered drug carriers such as elastin-like polypeptides, silk-like polypeptides, and silk-elastin-like protein polymers, and non-polymeric genetically engineered drug carriers such as vault proteins and viral proteins. PMID:24741309

Development of scanning graphene Hall probes for magnetic microscopy

NASA Astrophysics Data System (ADS)

Schaefer, Brian T.; Wang, Lei; McEuen, Paul L.; Nowack, Katja C.

We discuss our progress on developing scanning Hall probes fabricated from hexagonal boron nitride (hBN)-encapsulated graphene, with the goal to image magnetic fields with submicron resolution. In contrast to scanning superconducting quantum interference device (SQUID) microscopy, this technique is compatible with a large applied magnetic field and not limited to cryogenic temperatures. The field sensitivity of a Hall probe depends inversely on carrier density, while the primary source of noise in the measurement is Johnson noise originating from the device resistance. hBN-encapsulated graphene demonstrates high carrier mobility at low carrier densities, therefore making it an ideal material for sensitive Hall probes. Furthermore, engineering the dielectric environment of graphene by encapsulating in hBN reduces low-frequency charge noise and disorder from the substrate. We outline our plans for adapting these devices for scanning, including characterization of the point spread function with a scanned current loop and fabrication of a deep-etched structure that enables positioning the sensitive area within 100 nanometers of the sample surface.

CARRIAGE OF THE VIRUS OF POLIOMYELITIS, WITH SUBSEQUENT DEVELOPMENT OF THE INFECTION.

PubMed

Taylor, E; Amoss, H L

1917-11-01

A family group containing four children of whom all showed in varying degree symptoms of poliomyelitis is described. The source of infection and periods of incubation have been followed. Two of the children were proven by inoculation tests to carry the virus of poliomyelitis in the nasopharynx. Of these, one was detected to be a carrier after recovering from a non-paralytic attack of the disease, and the other was discovered to be a carrier about 5 days before the initial symptoms, attended later by paralysis, appeared. The original case from which the three others took origin was fatal; the youngest child, after quite a severe onset, was treated with immune serum, and made a prompt and almost perfect recovery. The nasopharyngeal secretions of two of the cases, taken 1 month after the attack, proved incapable of neutralizing an active poliomyelitic virus. The proposition is presented that every case of poliomyelitis develops from a carrier of the microbic cause, or virus, of poliomyelitis.

Multiple Payload Ejector for Education, Science and Technology Experiments

NASA Technical Reports Server (NTRS)

Lechworth, Gary

2005-01-01

The education research community no longer has a means of being manifested on Space Shuttle flights, and small orbital payload carriers must be flown as secondary payloads on ELV flights, as their launch schedule, secondary payload volume and mass permits. This has resulted in a backlog of small payloads, schedule and cost problems, and an inability for the small payloads community to achieve routine, low-cost access to orbit. This paper will discuss Goddard's Wallops Flight Facility funded effort to leverage its core competencies in small payloads, sounding rockets, balloons and range services to develop a low cost, multiple payload ejector (MPE) carrier for orbital experiments. The goal of the MPE is to provide a low-cost carrier intended primarily for educational flight research experiments. MPE can also be used by academia and industry for science, technology development and Exploration experiments. The MPE carrier will take advantage of the DARPAI NASA partnership to perform flight testing of DARPA s Falcon small, demonstration launch vehicle. The Falcon is similar to MPE fiom the standpoint of focusing on a low-cost, responsive system. Therefore, MPE and Falcon complement each other for the desired long-term goal of providing the small payloads community with a low-cost ride to orbit. The readiness dates of Falcon and MPE are complementary, also. MPE is being developed and readied for flight within 18 months by a small design team. Currently, MPE is preparing for Critical Design Review in fall 2005, payloads are being manifested on the first mission, and the carrier will be ready for flight on the first Falcon demonstration flight in summer, 2006. The MPE and attached experiments can weigh up to 900 lb. to be compatible with Falcon demonstration vehicle lift capabilities fiom Wallops, and will be delivered to the Falcon demonstration orbit - 100 nautical mile circular altitude.

Ultrasonic coupling to optically generated charge carriers in CdS: Physical phenomena and applications. Ph.D. Thesis - Washington Univ., Saint Louis, Mo.

NASA Technical Reports Server (NTRS)

Heyman, J. S.

1975-01-01

Phonon-charge carrier interactions are studied as well as ultrasonic resonators. Sensitivity enhancement factors predicted by one dimensional resonator theory are verified and several sensitive ultrasonic experimental techniques are developed. Measurements are reported of an anomalous sign reversal of the acoustoelectric voltage in a CdS resonator. Applications of CdS as an ultrasonic power detector are described.

Piezophototronic Effect in Single-Atomic-Layer MoS2 for Strain-Gated Flexible Optoelectronics.

PubMed

Wu, Wenzhuo; Wang, Lei; Yu, Ruomeng; Liu, Yuanyue; Wei, Su-Huai; Hone, James; Wang, Zhong Lin

2016-10-01

Strain-gated flexible optoelectronics are reported based on monolayer MoS 2 . Utilizing the piezoelectric polarization created at the metal-MoS 2 interface to modulate the separation/transport of photogenerated carriers, the piezophototronic effect is applied to implement atomic-layer-thick phototransistor. Coupling between piezoelectricity and photogenerated carriers may enable the development of novel optoelectronics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Shuttle Carrier Aircraft

NASA Image and Video Library

2014-04-23

It has been called the world's greatest piggyback ride: a space shuttle, atop a Boeing 747 jet aircraft. But this is no ordinary 747, this is the Shuttle Carrier Aircraft...the SCA. This specially modified jumbo jet was not only a taxi service for the shuttle, but also helped in the development of the shuttle itself. In 30 years of flying, the majestic image of a spacecraft joined to the SCA, became a symbol of American invention and ingenuity.

Performance evaluation of a mobile satellite system modem using an ALE method

NASA Technical Reports Server (NTRS)

Ohsawa, Tomoki; Iwasaki, Motoya

1990-01-01

Experimental performance of a newly designed demodulation concept is presented. This concept applies an Adaptive Line Enhancer (ALE) to a carrier recovery circuit, which makes pull-in time significantly shorter in noisy and large carrier offset conditions. This new demodulation concept was actually developed as an INMARSAT standard-C modem, and was evaluated. On a performance evaluation, 50 symbol pull-in time is confirmed under 4 dB Eb/No condition.

Production and characterization of nanostructured lipid carriers and solid lipid nanoparticles containing lycopene for food fortification.

PubMed

Akhoond Zardini, Ali; Mohebbi, Mohebbat; Farhoosh, Reza; Bolurian, Shadi

2018-01-01

In this study, lycopene, was loaded on nanostructured lipid carrier and solid lipid nanoparticles using combination of high shear homogenization and ultrasonication method. Effect of applied lipids types, nanocarrier's type and lycopene loading on physicochemical properties of developed nanocarriers were studied. Particle sizes of developed nanocarriers were between 74.93 and 183.40 nm. Encapsulation efficiency of nanostructured lipid carrier was significantly higher than solid lipid nanoparticles. Morphological study of developed nanocarriers using scanning electron microscopy showed spherical nanoparticles with smooth surface. Lycopene was entrapped in nanocarriers without any chemical interaction with coating material according to Fourier transform infrared spectroscopy spectrum and differential scanning calorimetry thermogram. Glycerol monostearate containing nanoparticles showed phase separation after 30 days in 6 and 25 °C, whereas this event was not observed in nanosuspensions that produced by glycerol distearate. Lycopene release in gastrointestinal condition was studied by the dialysis bag method. To evaluate nanocarrier's potential for food fortification, developed lycopene-loaded nanocarriers were added to orange drink. Results of sensory analysis indicated that nanoencapsulation could obviate the poor solubility and tomato after taste of lycopene. Fortified sample with lycopene nanocarriers didn't show significant difference with blank orange drink sample except in orange odor.

Ultrasensitive photodetectors exploiting electrostatic trapping and percolation transport

DOE PAGES

Zhang, Yingjie; Hellebusch, Daniel J.; Bronstein, Noah D.; ...

2016-06-21

The sensitivity of semiconductor photodetectors is limited by photocarrier recombination during the carrier transport process. We developed a new photoactive material that reduces recombination by physically separating hole and electron charge carriers. This material has a specific detectivity (the ability to detect small signals) of 5 × 10 17 Jones, the highest reported in visible and infrared detectors at room temperature, and 4-5 orders of magnitude higher than that of commercial single-crystal silicon detectors. The material was fabricated by sintering chloride-capped CdTe nanocrystals into polycrystalline films, where Cl selectively segregates into grain boundaries acting as n-type dopants. Photogenerated electrons concentratemore » in and percolate along the grain boundaries - a network of energy valleys, while holes are confined in the grain interiors. This electrostatic field-assisted carrier separation and percolation mechanism enables an unprecedented photoconductive gain of 10 10 e - per photon, and allows for effective control of the device response speed by active carrier quenching.« less

Direct and simultaneous observation of ultrafast electron and hole dynamics in germanium

DOE PAGES

Zurch, Michael; Chang, Hung -Tzu; Borja, Lauren J.; ...

2017-06-01

Understanding excited carrier dynamics in semiconductors is crucial for the development of photovoltaics and efficient photonic devices. However, overlapping spectral features in optical pump-probe spectroscopy often render assignments of separate electron and hole carrier dynamics ambiguous. Here, ultrafast electron and hole dynamics in germanium nanocrystalline thin films are directly and simultaneously observed by ultrafast transient absorption spectroscopy in the extreme ultraviolet at the germanium M 4,5 edge. We decompose the spectra into contributions of electronic state blocking and photo-induced band shifts at a carrier density of 8 × 10 20 cm –3. Separate electron and hole relaxation times are observedmore » as a function of hot carrier energies. A first-order electron and hole decay of ~1 ps suggests a Shockley–Read–Hall recombination mechanism. Furthermore, the simultaneous observation of electrons and holes with extreme ultraviolet transient absorption spectroscopy paves the way for investigating few- to sub-femtosecond dynamics of both holes and electrons in complex semiconductor materials and across junctions.« less

Anisotropic carrier mobility in buckled two-dimensional GaN.

PubMed

Tong, Lijia; He, Junjie; Yang, Min; Chen, Zheng; Zhang, Jing; Lu, Yanli; Zhao, Ziyuan

2017-08-30

Developing nanoelectronic engineering requires two-dimensional (2d) materials with both usable carrier mobility and proper large band-gap. In this study, we present a detailed theoretical investigation of the intrinsic carrier mobilities of buckled 2d GaN. This buckled 2d GaN is accessed by hydrofluorination (FGaNH) and hydrogenation (HGaNH). We predict that the anisotropic carrier mobilities of buckled 2d GaN can exceed those of 2d MoS 2 and can be altered by an alterable surface chemical bond (convert from a Ga-F-Ga bond of FGaNH to a Ga-H bond of HGaNH). Moreover, converting FGaNH to HGaNH can significantly suppress hole mobility (even close to zero) and result in a transition from a p-type-like semiconductor (FGaNH) to an n-type-like semiconductor (HGaNH). These features make buckled 2d GaN a promising candidate for application in future conductivity-adjustable electronics.

Ultrasensitive photodetectors exploiting electrostatic trapping and percolation transport

PubMed Central

Zhang, Yingjie; Hellebusch, Daniel J.; Bronstein, Noah D.; Ko, Changhyun; Ogletree, D. Frank; Salmeron, Miquel; Alivisatos, A. Paul

2016-01-01

The sensitivity of semiconductor photodetectors is limited by photocarrier recombination during the carrier transport process. We developed a new photoactive material that reduces recombination by physically separating hole and electron charge carriers. This material has a specific detectivity (the ability to detect small signals) of 5 × 1017 Jones, the highest reported in visible and infrared detectors at room temperature, and 4–5 orders of magnitude higher than that of commercial single-crystal silicon detectors. The material was fabricated by sintering chloride-capped CdTe nanocrystals into polycrystalline films, where Cl selectively segregates into grain boundaries acting as n-type dopants. Photogenerated electrons concentrate in and percolate along the grain boundaries—a network of energy valleys, while holes are confined in the grain interiors. This electrostatic field-assisted carrier separation and percolation mechanism enables an unprecedented photoconductive gain of 1010 e− per photon, and allows for effective control of the device response speed by active carrier quenching. PMID:27323904

Antibiotic-containing hyaluronic acid gel as an antibacterial carrier: Usefulness of sponge and film-formed HA gel in deep infection.

PubMed

Matsuno, Hiroaki; Yudoh, Kazuo; Hashimoto, Masamichi; Himeda, Yasukazu; Miyoshi, Teruzo; Yoshida, Kaoru; Kano, Syogo

2006-03-01

We have developed a novel bioabsorbable antibacterial carrier using hyaluronic acid (HA) gel for prevention and treatment of orthopedic infections. In this study, we investigated the in vivo antibacterial effects of two forms of this new material, an HA gel sponge and an HA gel film. A titanium cylinder was inserted into the intramedullary cavity of each rabbit femur, along with an HA gel sponge or HA gel film containing antibiotics. The HA gel sponge contained gentamycin, vancomycin, tobramycin, or minomycin. The HA gel film contained gentamycin or vancomycin. After 0, 7, and 14 days, the rabbit bone marrow was collected, and the antibacterial activity of the HA gel was determined by agar diffusion test. As a control, we used Septocoll, a commercially available antibacterial carrier. Both the HA gel sponge and HA gel film exhibited antibacterial activity. The present results indicate that HA gel containing antibiotics is a clinically useful bioabsorbable antibacterial carrier. Copyright 2006 Orthopaedic Research Society.

A new coherent demodulation technique for land-mobile satellite communications

NASA Technical Reports Server (NTRS)

Yoshida, Shousei; Tomita, Hideho

1990-01-01

An advanced coherent demodulation technique is described for land mobile satellite (LMS) communications. The proposed technique features a combined narrow/wind band dual open loop carrier phase estimator, which is effectively able to compensate the fast carrier phase fluctuation by fading with sacrificing a phase slip rate. Also included is the realization of quick carrier and clock reacquisition after shadowing by taking open loop structure. Its bit error rate (BER) performance is superior to that of existing detection schemes, showing a BER of 1 x 10(exp -2) at 6.3 dB E sub b/N sub o over the Rician channel with 10 dB C/M and 200 Hz (1/16 modulation rate) fading pitch f sub d for QPSK. The proposed scheme consists of a fast response carrier recovery and a quick bit timing recovery with an interpolation. An experimental terminal model was developed to evaluate its performance at fading conditions. The results are quite satisfactory, giving prospects for future LMS applications.

A novel liquid organic hydrogen carrier system based on catalytic peptide formation and hydrogenation

PubMed Central

Hu, Peng; Fogler, Eran; Diskin-Posner, Yael; Iron, Mark A.; Milstein, David

2015-01-01

Hydrogen is an efficient green fuel, but its low energy density when stored under high pressure or cryogenically, and safety issues, presents significant disadvantages; hence finding efficient and safe hydrogen carriers is a major challenge. Of special interest are liquid organic hydrogen carriers (LOHCs), which can be readily loaded and unloaded with considerable amounts of hydrogen. However, disadvantages include high hydrogen pressure requirements, high reaction temperatures for both hydrogenation and dehydrogenation steps, which require different catalysts, and high LOHC cost. Here we present a readily reversible LOHC system based on catalytic peptide formation and hydrogenation, using an inexpensive, safe and abundant organic compound with high potential capacity to store and release hydrogen, applying the same catalyst for loading and unloading hydrogen under relatively mild conditions. Mechanistic insight of the catalytic reaction is provided. We believe that these findings may lead to the development of an inexpensive, safe and clean liquid hydrogen carrier system. PMID:25882348

Direct and simultaneous observation of ultrafast electron and hole dynamics in germanium

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

Zurch, Michael; Chang, Hung -Tzu; Borja, Lauren J.

Understanding excited carrier dynamics in semiconductors is crucial for the development of photovoltaics and efficient photonic devices. However, overlapping spectral features in optical pump-probe spectroscopy often render assignments of separate electron and hole carrier dynamics ambiguous. Here, ultrafast electron and hole dynamics in germanium nanocrystalline thin films are directly and simultaneously observed by ultrafast transient absorption spectroscopy in the extreme ultraviolet at the germanium M 4,5 edge. We decompose the spectra into contributions of electronic state blocking and photo-induced band shifts at a carrier density of 8 × 10 20 cm –3. Separate electron and hole relaxation times are observedmore » as a function of hot carrier energies. A first-order electron and hole decay of ~1 ps suggests a Shockley–Read–Hall recombination mechanism. Furthermore, the simultaneous observation of electrons and holes with extreme ultraviolet transient absorption spectroscopy paves the way for investigating few- to sub-femtosecond dynamics of both holes and electrons in complex semiconductor materials and across junctions.« less

Enhanced carrier multiplication in engineered quasi-type-II quantum dots

PubMed Central

Cirloganu, Claudiu M.; Padilha, Lazaro A.; Lin, Qianglu; Makarov, Nikolay S.; Velizhanin, Kirill A.; Luo, Hongmei; Robel, Istvan; Pietryga, Jeffrey M.; Klimov, Victor I.

2014-01-01

One process limiting the performance of solar cells is rapid cooling (thermalization) of hot carriers generated by higher-energy solar photons. In principle, the thermalization losses can be reduced by converting the kinetic energy of energetic carriers into additional electron-hole pairs via carrier multiplication (CM). While being inefficient in bulk semiconductors this process is enhanced in quantum dots, although not sufficiently high to considerably boost the power output of practical devices. Here we demonstrate that thick-shell PbSe/CdSe nanostructures can show almost a fourfold increase in the CM yield over conventional PbSe quantum dots, accompanied by a considerable reduction of the CM threshold. These structures enhance a valence-band CM channel due to effective capture of energetic holes into long-lived shell-localized states. The attainment of the regime of slowed cooling responsible for CM enhancement is indicated by the development of shell-related emission in the visible observed simultaneously with infrared emission from the core. PMID:24938462

Dependence of Mobility on Density of Gap States in Organics by GAMEaS - Gate Modulated Activation Energy Spectroscopy

NASA Astrophysics Data System (ADS)

So, Woo-Young; Lang, David; Ramirez, Arthur

2008-03-01

We develop a spectroscopic method for determining the density of states (DOS) in the energy gap - GAte Modulated activation Energy Spectroscopy (GAMEaS), We also report the relationship of these gap states to the mobility of organic field-effect-transistors (FETs). We find that the field-effect mobility is parameterized by two factors: (1) the free-carrier mobility and (2) the ratio of the free carrier density to the total carrier density induced by the gate bias. We show that the highest mobility FETs have shallow exponential band tails of localized states with characteristic slope of 1/kT at 300K. Most remarkably, state-of-the-art crystalline FETs fabricated from rubrene, pentacene, and tetracene all have a very high free-carrier mobility, up to 200cm2/Vsec at 300K, with the somewhat lower effective mobilities dominated by localized gap states. This strongly suggests that further improvements in device performance could be possible with enhanced material quality.

Direct and simultaneous observation of ultrafast electron and hole dynamics in germanium.

PubMed

Zürch, Michael; Chang, Hung-Tzu; Borja, Lauren J; Kraus, Peter M; Cushing, Scott K; Gandman, Andrey; Kaplan, Christopher J; Oh, Myoung Hwan; Prell, James S; Prendergast, David; Pemmaraju, Chaitanya D; Neumark, Daniel M; Leone, Stephen R

2017-06-01

Understanding excited carrier dynamics in semiconductors is crucial for the development of photovoltaics and efficient photonic devices. However, overlapping spectral features in optical pump-probe spectroscopy often render assignments of separate electron and hole carrier dynamics ambiguous. Here, ultrafast electron and hole dynamics in germanium nanocrystalline thin films are directly and simultaneously observed by ultrafast transient absorption spectroscopy in the extreme ultraviolet at the germanium M 4,5 edge. We decompose the spectra into contributions of electronic state blocking and photo-induced band shifts at a carrier density of 8 × 10 20  cm -3 . Separate electron and hole relaxation times are observed as a function of hot carrier energies. A first-order electron and hole decay of ∼1 ps suggests a Shockley-Read-Hall recombination mechanism. The simultaneous observation of electrons and holes with extreme ultraviolet transient absorption spectroscopy paves the way for investigating few- to sub-femtosecond dynamics of both holes and electrons in complex semiconductor materials and across junctions.

Direct and simultaneous observation of ultrafast electron and hole dynamics in germanium

PubMed Central

Zürch, Michael; Chang, Hung-Tzu; Borja, Lauren J.; Kraus, Peter M.; Cushing, Scott K.; Gandman, Andrey; Kaplan, Christopher J.; Oh, Myoung Hwan; Prell, James S.; Prendergast, David; Pemmaraju, Chaitanya D.; Neumark, Daniel M.; Leone, Stephen R.

2017-01-01

Understanding excited carrier dynamics in semiconductors is crucial for the development of photovoltaics and efficient photonic devices. However, overlapping spectral features in optical pump-probe spectroscopy often render assignments of separate electron and hole carrier dynamics ambiguous. Here, ultrafast electron and hole dynamics in germanium nanocrystalline thin films are directly and simultaneously observed by ultrafast transient absorption spectroscopy in the extreme ultraviolet at the germanium M4,5 edge. We decompose the spectra into contributions of electronic state blocking and photo-induced band shifts at a carrier density of 8 × 1020 cm−3. Separate electron and hole relaxation times are observed as a function of hot carrier energies. A first-order electron and hole decay of ∼1 ps suggests a Shockley–Read–Hall recombination mechanism. The simultaneous observation of electrons and holes with extreme ultraviolet transient absorption spectroscopy paves the way for investigating few- to sub-femtosecond dynamics of both holes and electrons in complex semiconductor materials and across junctions. PMID:28569752

Tremor-Ataxia syndrome and primary ovarian insufficiency in anFMR1 premutation carrier

PubMed Central

Rodriguez-Guerrero, Tatiana; Fandiño-Losada, Andres; Ramirez-Cheyne, Julian

2017-01-01

Abstract Introduction: The FMR1 gene has four allelic variants according to the number of repeats of the CGG triplet. Premutation carriers with between 55 and 200 repeats are susceptible to developing pathologies such as tremor and ataxia syndrome (FXTAS) and fragile X-associated primary ovarian insufficiency (FXPOI) syndrome. Case description: The patient was a 53-year-old female farmer with severe tremor in the upper limbs at rest that worsens with movement, tremor in the jaw and tongue, and generalized cerebral atrophy. She is a carrier of the FMR1 premutation diagnosed by PCR and Southern Blot, complying with the clinical and radiological criteria of FXTAS, and in addition, has a history of vagal symptoms suggestive of ovarian failure and menstrual cycle disorders that led to hysterectomy at age 33 and was subsequently diagnosed with FXPOI. Conclusion: An unusual case of FXTAS and FXPOI complying with clinical and radiological criteria is reported in a premutation carrier of the FMR1 gene. PMID:29299012

[Nanoscale drug carriers for traditional Chinese medicine research and development].

PubMed

Yi, Cheng-xue; Yu, Jiang-nan; Xu, Xi-ming

2008-08-01

Nanocarriers generally made of natural or artificial polymers ranging in size from about 10-1 000 nm, possess versatile properties suitable for drug delivery, including good biocompatibility and biodegradability, potential capability of targeted delivery and controlled release of incorporated drugs, and have been extensively used in the development of new drug delivery systems (DDS). These types of nano-DDS have considerable potential to traditional Chinese medicine (TCM), and recently have attracted increasing efforts on the TCM research and development. In this review, the recently published literature worldwide is covered to describe the latest advances in the applications as TCM delivery carriers, and to highlight the characteristics and preparation methods of some selected examples of promising nanocarriers such as nanoparticles, lipid nanoparticles, nanoemulsions, nanomicelles and nanoliposomes.

Targeting cancer with hyaluronic acid-based nanocarriers: recent advances and translational perspectives.

PubMed

Cadete, Ana; Alonso, María José

2016-09-01

Hyaluronic acid is a natural polysaccharide that has been widely explored for the development of anticancer therapies due to its ability to target cancer cells. Moreover, advances made in the last decade have revealed the versatility of this biomaterial in the design of multifunctional carriers, intended for the delivery of a variety of bioactive molecules, including polynucleotides, immunomodulatory drugs and imaging agents. In this review, we aim to provide an overview of the major recent achievements in this field, highlighting the application of the newly developed nanostructures in combination therapies, immunomodulation and theranostics. Finally, we will discuss the main challenges and technological advances that will allow these carriers to be considered as candidates for clinical development.

Early behavioural changes in familial Alzheimer's disease in the Dominantly Inherited Alzheimer Network.

PubMed

Ringman, John M; Liang, Li-Jung; Zhou, Yan; Vangala, Sitaram; Teng, Edmond; Kremen, Sarah; Wharton, David; Goate, Alison; Marcus, Daniel S; Farlow, Martin; Ghetti, Bernardino; McDade, Eric; Masters, Colin L; Mayeux, Richard P; Rossor, Martin; Salloway, Stephen; Schofield, Peter R; Cummings, Jeffrey L; Buckles, Virginia; Bateman, Randall; Morris, John C

2015-04-01

Prior studies indicate psychiatric symptoms such as depression, apathy and anxiety are risk factors for or prodromal symptoms of incipient Alzheimer's disease. The study of persons at 50% risk for inheriting autosomal dominant Alzheimer's disease mutations allows characterization of these symptoms before progressive decline in a population destined to develop illness. We sought to characterize early behavioural features in carriers of autosomal dominant Alzheimer's disease mutations. Two hundred and sixty-one persons unaware of their mutation status enrolled in the Dominantly Inherited Alzheimer Network, a study of persons with or at-risk for autosomal dominant Alzheimer's disease, were evaluated with the Neuropsychiatric Inventory-Questionnaire, the 15-item Geriatric Depression Scale and the Clinical Dementia Rating Scale (CDR). Ninety-seven asymptomatic (CDR = 0), 25 mildly symptomatic (CDR = 0.5), and 33 overtly affected (CDR > 0.5) autosomal dominant Alzheimer's disease mutation carriers were compared to 106 non-carriers with regard to frequency of behavioural symptoms on the Neuropsychiatric Inventory-Questionnaire and severity of depressive symptoms on the Geriatric Depression Scale using generalized linear regression models with appropriate distributions and link functions. Results from the adjusted analyses indicated that depressive symptoms on the Neuropsychiatric Inventory-Questionnaire were less common in cognitively asymptomatic mutation carriers than in non-carriers (5% versus 17%, P = 0.014) and the odds of experiencing at least one behavioural sign in cognitively asymptomatic mutation carriers was lower than in non-carriers (odds ratio = 0.50, 95% confidence interval: 0.26-0.98, P = 0.042). Depression (56% versus 17%, P = 0.0003), apathy (40% versus 4%, P < 0.0001), disinhibition (16% versus 2%, P = 0.009), irritability (48% versus 9%, P = 0.0001), sleep changes (28% versus 7%, P = 0.003), and agitation (24% versus 6%, P = 0.008) were more common and the degree of self-rated depression more severe (mean Geriatric Depression Scale score of 2.8 versus 1.4, P = 0.006) in mildly symptomatic mutation carriers relative to non-carriers. Anxiety, appetite changes, delusions, and repetitive motor activity were additionally more common in overtly impaired mutation carriers. Similar to studies of late-onset Alzheimer's disease, we demonstrated increased rates of depression, apathy, and other behavioural symptoms in the mildly symptomatic, prodromal phase of autosomal dominant Alzheimer's disease that increased with disease severity. We did not identify any increased psychopathology in mutation carriers over non-carriers during the presymptomatic stage, suggesting these symptoms result when a threshold of neurodegeneration is reached rather than as life-long qualities. Unexpectedly, we found lower rates of depressive symptoms in cognitively asymptomatic mutation carriers. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Template method for fabricating interdigitate p-n heterojunction for organic solar cell

PubMed Central

2012-01-01

Anodic aluminum oxide (AAO) templates are used to fabricate arrays of poly(3-hexylthiophene) (P3HT) pillars. This technique makes it possible to control the dimensions of the pillars, namely their diameters, intervals, and heights, on a tens-of-nanometer scale. These features are essential for enhancing carrier processes such as carrier generation, exciton diffusion, and carrier dissociation and transport. An interdigitated p-n junction between P3HT pillars and fullerene (C60) exhibits a photovoltaic effect. Although the device properties are still preliminary, the experimental results indicate that an AAO template is an effective tool with which to develop organic solar cells because highly regulated nanostructures can be produced on large areas exceeding 100 mm2. PMID:22908897

Nanostructured lipid carriers: versatile oral delivery vehicle

PubMed Central

Poonia, Neelam; Kharb, Rajeev; Lather, Viney; Pandita, Deepti

2016-01-01

Oral delivery is the most accepted and economical route for drug administration and leads to substantial reduction in dosing frequency. However, this route still remains a challenge for the pharmaceutical industry due to poorly soluble and permeable drugs leading to poor oral bioavailability. Incorporating bioactives into nanostructured lipid carriers (NLCs) has helped in boosting their therapeutic functionality and prolonged release from these carrier systems thus providing improved pharmacokinetic parameters. The present review provides an overview of noteworthy studies reporting impending benefits of NLCs in oral delivery and highlights recent advancements for developing engineered NLCs either by conjugating polymers over their surface or modifying their charge to overcome the mucosal barrier of GI tract for active transport across intestinal membrane. PMID:28031979

Hitchhiker capabilities

NASA Technical Reports Server (NTRS)

Goldsmith, Theodore C.

1988-01-01

A carrier system has been developed for economical and quick response flight of small attached payloads on the space shuttle. Hitchhiker can accommodate up to 750 lb of customer payloads in canisters or mounted to an exposed side-mount plate, or up to 1200 lb mounted on a cross-bay structure. The carrier connects to the orbiter's electrical systems and provides up to six customers with standard electrical services including power, real time telemetry and commands. A transparent data and command system concept is employed to allow the customer to easily use his own ground support equipment and personnel to control his payload during integration and flight operations. A general description of the Hitchhiker program and the Shuttle Payload of Opportunity Carrier (SPOC) is given and future enhancements are outlined.

Time resolved photo-luminescent decay characterization of mercury cadmium telluride focal plane arrays

DOE PAGES

Soehnel, Grant

2015-01-20

The minority carrier lifetime is a measurable material property that is an indication of infrared detector device performance. To study the utility of measuring the carrier lifetime, an experiment has been constructed that can time resolve the photo-luminescent decay of a detector or wafer sample housed inside a liquid nitrogen cooled Dewar. Motorized stages allow the measurement to be scanned over the sample surface, and spatial resolutions as low as 50µm have been demonstrated. A carrier recombination simulation was developed to analyze the experimental data. Results from measurements performed on 4 mercury cadmium telluride focal plane arrays show strong correlationmore » between spatial maps of the lifetime, dark current, and relative response.« less

Insulin resistance, dyslipidemia, and apolipoprotein E interactions as mechanisms in cognitive impairment and Alzheimer's disease

PubMed Central

Salameh, Therese S; Rhea, Elizabeth M; Hanson, Angela J

2016-01-01

An increased risk for Alzheimer's disease is associated with dyslipidemia and insulin resistance. A separate literature shows the genetic risk for developing Alzheimer's disease is strongly correlated to the presence of the E4 isoform of the apolipoprotein E carrier protein. Understanding how apolipoprotein E carrier protein, lipids, amyloid β peptides, glucose, central nervous system insulin, and peripheral insulin interact with one another in Alzheimer's disease is an area of increasing interest. Here, we will review the evidence relating apolipoprotein E carrier protein, lipids, and insulin action to Alzheimer's disease and Aβ peptides and then propose mechanisms as to how these factors might interact with one another to impair cognition and promote Alzheimer's disease. PMID:27470930

Candidal carriage predicts candidiasis during topical immunosuppressive therapy: a preliminary retrospective cohort study.

PubMed

Tejani, Sara; Sultan, Ahmed; Stojanov, Ivan; Woo, Sook-Bin

2016-10-01

To determine (1) the prevalence of candidal carriage in patients with oral mucosal disease to be treated with topical immunosuppressive therapy, and (2) the incidence of oral candidiasis among carriers and noncarriers after initiation of therapy to assess any correlation between carriage and the development of candidiasis. Records of patients who underwent swab cultures for Candida between January 2009 and October 2014 at the Brigham and Women's Hospital in Boston, Massachusetts, were retrospectively reviewed. The prevalence of candidal carriage and incidence of candidiasis were determined by using descriptive statistics. Of 99 evaluable patients, 20 (20.2%) were Candida positive and 79 (79.8%) were Candida negative. Of 44 patients with follow-up, 7 (15.9%) were Candida positive and 37 (84.1%) were Candida negative; five (11.4%) developed candidiasis. Four of seven (57.1%) Candida-positive patients developed candidiasis, whereas only one of 37 (2.7%) Candida-negative patients developed candidiasis (P = .0012). The overall prevalence of candidal carriage was low (20.2%), and there was a significant difference in the incidence of candidiasis between carriers and noncarriers (P = .0012) after topical immunosuppressive therapy. Therefore, patients who are candidal carriers should be monitored closely for the development of secondary candidiasis and may be candidates for prophylactic antifungal therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Computer-assisted techniques to evaluate fringe patterns

NASA Astrophysics Data System (ADS)

Sciammarella, Cesar A.; Bhat, Gopalakrishna K.

1992-01-01

Strain measurement using interferometry requires an efficient way to extract the desired information from interferometric fringes. Availability of digital image processing systems makes it possible to use digital techniques for the analysis of fringes. In the past, there have been several developments in the area of one dimensional and two dimensional fringe analysis techniques, including the carrier fringe method (spatial heterodyning) and the phase stepping (quasi-heterodyning) technique. This paper presents some new developments in the area of two dimensional fringe analysis, including a phase stepping technique supplemented by the carrier fringe method and a two dimensional Fourier transform method to obtain the strain directly from the discontinuous phase contour map.

Development of a (Hg, Cd)Te photodiode detector, Phase 2. [for 10.6 micron spectral region

NASA Technical Reports Server (NTRS)

1972-01-01

High speed sensitive (Hg,Cd)Te photodiode detectors operating in the 77 to 90 K temperature range have been developed for the 10.6 micron spectral region. P-N junctions formed by impurity (gold) diffusion in p-type (Hg, Cd) Te have been investigated. It is shown that the bandwidth and quantum efficiency of a diode are a constant for a fixed ratio of mobility/lifetime ratio of minority carriers. The minority carrier mobility and lifetime uniquely determine the bandwidth and quantum efficiency and indicate the shallow n on p (Hg,Cd) Te diodes are preferable as high performance, high frequency devices.

Cosegregation and functional analysis of mutant ABCR (ABCA4) alleles in families that manifest both Stargardt disease and age-related macular degeneration.

PubMed

Shroyer, N F; Lewis, R A; Yatsenko, A N; Wensel, T G; Lupski, J R

2001-11-01

Mutations in ABCR (ABCA4) have been reported to cause a spectrum of autosomal recessively inherited retinopathies, including Stargardt disease (STGD), cone-rod dystrophy and retinitis pigmentosa. Individuals heterozygous for ABCR mutations may be predisposed to develop the multifactorial disorder age-related macular degeneration (AMD). We hypothesized that some carriers of STGD alleles have an increased risk to develop AMD. We tested this hypothesis in a cohort of families that manifest both STGD and AMD. With a direct-sequencing mutation detection strategy, we found that AMD-affected relatives of STGD patients are more likely to be carriers of pathogenic STGD alleles than predicted based on chance alone. We further investigated the role of AMD-associated ABCR mutations by testing for expression and ATP-binding defects in an in vitro biochemical assay. We found that mutations associated with AMD have a range of assayable defects ranging from no detectable defect to apparent null alleles. Of the 21 missense ABCR mutations reported in patients with AMD, 16 (76%) show abnormalities in protein expression, ATP-binding or ATPase activity. We infer that carrier relatives of STGD patients are predisposed to develop AMD.

ELaNa - Educational Launch of Nanosatellite Providing Routine RideShare Opportunities

NASA Technical Reports Server (NTRS)

Skrobot, Garrett Lee; Coelho, Roland

2012-01-01

Since the creation of the NASA CubeSat Launch Initiative (NCSLI), the need for CubeSat rideshares has dramatically increased. After only three releases of the initiative, a total of 66 CubeSats now await launch opportunities. So, how is this challenge being resolved? NASA's Launch Services Program (LSP) has studied how to integrate PPODs on Athena, Atlas V, and Delta IV launch vehicles and has been instrumental in developing several carrier systems to support CubeSats as rideshares on NASA missions. In support of the first two ELaNa missions the Poly-Picosatellite Orbital Deployer (P-POD) was adapted for use on a Taurus XL (ELaNa I) and a Delta n (ELaNa III). Four P-PODs, which contained a total eight CubeSats, were used on these first ELaNa missions. Next up is ELaNa VI, which will launch on an Atlas V in August 2012. The four ELaNa VI CubeSats, in three P-PODs, are awaiting launch, having been integrated in the NPSCuLite. To increase rideshare capabilities, the Launch Services Program (LSP) is working to integrate P-PODs on Falcon 9 missions. The proposed Falcon 9 manifest will provide greater opportunities for the CubeSat community. For years, the standard CubeSat size was 1 U to 3U. As the desire to include more science in each cube grows, so does the standard CubeSat size. No longer is a 1 U, 1.5U, 2U or 3U CubeSat the only option available; the new CubeSat standard will include 6U and possibly even 12U. With each increase in CubeSat size, the CubeSat community is pushing the capability of the current P-POD design. Not only is the carrier system affected, but integration to the Launch Vehicle is also a concern. The development of a system to accommodate not only the 3U P-POD but also carriers for larger CubeSats is ongoing. LSP considers payloads in the lkg to 180 kg range rideshare or small/secondary payloads. As new and emerging small payloads are developed, rideshare opportunities and carrier systems need to be identified and secured. The development of a rideshare carrier system is not always cost effective. Sometimes a launch vehicle with an excellent performance record appears to be a great rideshare candidate however, after completing a feasibility study, LSP may determine that the cost of the rideshare carrier system is too great and, due to budget constraints, the development cannot go forward. With the current budget environment, one cost effective way to secure rideshare opportunities is to look for synergy with other government organizations that share the same interest.

Comprehensive approach to intrinsic charge carrier mobility in conjugated organic molecules, macromolecules, and supramolecular architectures.

PubMed

Saeki, Akinori; Koizumi, Yoshiko; Aida, Takuzo; Seki, Shu

2012-08-21

Si-based inorganic electronics have long dominated the semiconductor industry. However, in recent years conjugated polymers have attracted increasing attention because such systems are flexible and offer the potential for low-cost, large-area production via roll-to-roll processing. The state-of-the-art organic conjugated molecular crystals can exhibit charge carrier mobilities (μ) that nearly match or even exceed that of amorphous silicon (1-10 cm(2) V(-1) s(-1)). The mean free path of the charge carriers estimated from these mobilities corresponds to the typical intersite (intermolecular) hopping distances in conjugated organic materials, which strongly suggests that the conduction model for the electronic band structure only applies to μ > 1 cm(2) V(-1) s(-1) for the translational motion of the charge carriers. However, to analyze the transport mechanism in organic electronics, researchers conventionally use a disorder formalism, where μ is usually less than 1 cm(2) V(-1) s(-1) and dominated by impurities, disorders, or defects that disturb the long-range translational motion. In this Account, we discuss the relationship between the alternating-current and direct-current mobilities of charge carriers, using time-resolved microwave conductivity (TRMC) and other techniques including field-effect transistor, time-of-flight, and space-charge limited current. TRMC measures the nanometer-scale mobility of charge carriers under an oscillating microwave electric field with no contact between the semiconductors and the metals. This separation allows us to evaluate the intrinsic charge carrier mobility with minimal trapping effects. We review a wide variety of organic electronics in terms of their charge carrier mobilities, and we describe recent studies of macromolecules, molecular crystals, and supramolecular architecture. For example, a rigid poly(phenylene-co-ethynylene) included in permethylated cyclodextrin shows a high intramolecular hole mobility of 0.5 cm(2) V(-1) s(-1), based on a combination of flash-photolysis TRMC and transient absorption spectroscopy (TAS) measurements. Single-crystal rubrene showed an ambipolarity with anisotropic charge carrier transport along each crystal axis on the nanometer scale. Finally, we describe the charge carrier mobility of a self-assembled nanotube consisting of a large π-plane of hexabenzocoronene (HBC) partially appended with an electron acceptor. The local (intratubular) charge carrier mobility reached 3 cm(2) V(-1) s(-1) for the nanotubes that possessed well-ordered π-stacking, but it dropped to 0.7 cm(2) V(-1) s(-1) in regions that contained greater amounts of the electron acceptor because those molecules reduced the structural integrity of π-stacked HBC arrays. Interestingly, the long-range (intertubular) charge carrier mobility was on the order of 10(-4) cm(2) V(-1) s(-1) and monotonically decreased when the acceptor content was increased. These results suggest the importance of investigating charge carrier mobilities by frequency-dependent charge carrier motion for the development of more efficient organic electronic devices.

[Polymer and oligomer based doxorubicin carriers].

PubMed

Kik, Krzysztof; Lwow, Felicja; Szmigiero, Leszek

2007-01-01

Doxorubicin and other anthracycline derivatives play an important role in the treatment of many malignant diseases. Unfortunately, clinical effectiveness of this class of drugs is limited by cumulative cardiotoxicity which occurs in significant percentage of patients at cumulative dose in the range 450-600 mg/m2. Therefore, several strategies have been developed to reduce cardiotoxicity of doxorubicin and its analogues. One of the possible ways leading to the improvement of anticancer selectivity of doxorubicin is the design of polymer and olygomer carriers which may transport drug molecules more efficiently and more specifically. Synthetic polymers are of increasing interest as therapeutic agents owing to their enhanced pharmacokinetic profiles relative to small molecule drugs. Currently a new class of multifunctional polymers is being prepared that can "mask" biologically active compounds, such as cytotoxic agents, until they reach target sites, but which can then release the agent in situ to effect the therapy. The legitimacy of the development of polymer based doxorubicine carriers is supported by the growing number of clinical reports indicating that the use of hydrophilic polymers or polymer coated liposomes as a platform for delivery of the drug results in better therapeutic effects than the free drug. In this article we present the most promising strategies directed at the development of improved anthracycline drugs formulations based of polymer and olygomer carriers. We review: 1) polyethylenoglycol-coated ("pegylated") liposomal doxorubicin; 2) extracellulary tumor-activated prodrugs which are conjugates of doxorubicin with peptides; 3) doxorubicin coated by higly polymerised glycosoaminoglycans; 4) conjugates of doxorubicin with copolymer of N-(2-hydroxypropyl)methacrylamide.

77 FR 64431 - Civil Monetary Penalty Inflation Adjustment Rule

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-22

... Rail Carrier (Part A), Motor and Water Carriers (Part B), and Pipeline Carrier (Part C) provisions of... related to motor carriers, water carriers, brokers, and freight forwarders appears at 49 U.S.C. 14901... forwarders, Motor carriers, Pipeline carriers, Rail carriers, Water carriers. Decided: October 12, 2012. By...

Blood expression profiles of fragile X premutation carriers identify candidate genes involved in neurodegenerative and infertility phenotypes.

PubMed

Mateu-Huertas, Elisabet; Rodriguez-Revenga, Laia; Alvarez-Mora, Maria Isabel; Madrigal, Irene; Willemsen, Rob; Milà, Montserrat; Martí, Eulàlia; Estivill, Xavier

2014-05-01

Male premutation carriers presenting between 55 and 200 CGG repeats in the Fragile-X-associated (FMR1) gene are at risk of developing Fragile X Tremor/Ataxia Syndrome (FXTAS), and females undergo Premature Ovarian Failure (POF1). Here, we have evaluated gene expression profiles from blood in male FMR1 premutation carriers and detected a strong deregulation of genes enriched in FXTAS relevant biological pathways, including inflammation, neuronal homeostasis and viability. Gene expression profiling distinguished between control individuals, carriers with FXTAS and carriers without FXTAS, with levels of expanded FMR1 mRNA being increased in FXTAS patients. In vitro studies in a neuronal cell model indicate that expression levels of expanded FMR1 5'-UTR are relevant in modulating the transcriptome. Thus, perturbations of the transcriptome may be an interplay between the CGG expansion size and FMR1 expression levels. Several deregulated genes (DFFA, BCL2L11, BCL2L1, APP, SOD1, RNF10, HDAC5, KCNC3, ATXN7, ATXN3 and EAP1) were validated in brain samples of a FXTAS mouse model. Downregulation of EAP1, a gene involved in the female reproductive system physiology, was confirmed in female carriers. Decreased levels were detected in female carriers with POF1 compared to those without POF1, suggesting that EAP1 levels contribute to ovarian insufficiency. In summary, gene expression profiling in blood has uncovered mechanisms that may underlie different pathological aspects of the premutation. A better understanding of the transcriptome dynamics in relation with expanded FMR1 mRNA expression levels and CGG expansion size may provide mechanistic insights into the disease process and a more accurate FXTAS diagnosis to the myriad of phenotypes associated with the premutation. Copyright © 2014. Published by Elsevier Inc.

Survival analysis of cancer risk reduction strategies for BRCA1/2 mutation carriers.

PubMed

Kurian, Allison W; Sigal, Bronislava M; Plevritis, Sylvia K

2010-01-10

Women with BRCA1/2 mutations inherit high risks of breast and ovarian cancer; options to reduce cancer mortality include prophylactic surgery or breast screening, but their efficacy has never been empirically compared. We used decision analysis to simulate risk-reducing strategies in BRCA1/2 mutation carriers and to compare resulting survival probability and causes of death. We developed a Monte Carlo model of breast screening with annual mammography plus magnetic resonance imaging (MRI) from ages 25 to 69 years, prophylactic mastectomy (PM) at various ages, and/or prophylactic oophorectomy (PO) at ages 40 or 50 years in 25-year-old BRCA1/2 mutation carriers. With no intervention, survival probability by age 70 is 53% for BRCA1 and 71% for BRCA2 mutation carriers. The most effective single intervention for BRCA1 mutation carriers is PO at age 40, yielding a 15% absolute survival gain; for BRCA2 mutation carriers, the most effective single intervention is PM, yielding a 7% survival gain if performed at age 40 years. The combination of PM and PO at age 40 improves survival more than any single intervention, yielding 24% survival gain for BRCA1 and 11% for BRCA2 mutation carriers. PM at age 25 instead of age 40 offers minimal incremental benefit (1% to 2%); substituting screening for PM yields a similarly minimal decrement in survival (2% to 3%). Although PM at age 25 plus PO at age 40 years maximizes survival probability, substituting mammography plus MRI screening for PM seems to offer comparable survival. These results may guide women with BRCA1/2 mutations in their choices between prophylactic surgery and breast screening.

Olfaction in Parkin single and compound heterozygotes in a cohort of young onset Parkinson's disease patients.

PubMed

Malek, N; Swallow, D M A; Grosset, K A; Lawton, M A; Smith, C R; Bajaj, N P; Barker, R A; Ben-Shlomo, Y; Bresner, C; Burn, D J; Foltynie, T; Morris, H R; Williams, N; Wood, N W; Grosset, D G

2016-10-01

Parkin related Parkinson's disease (PD) is differentiated from idiopathic PD by absent or sparse Lewy bodies, and preserved olfaction. The significance of single Parkin mutations in the pathogenesis of PD is debated. To assess olfaction results according to Parkin mutation status. To compare the prevalence of Parkin single heterozygous mutations in patients diagnosed with PD to the rate in healthy controls in order to establish whether these single mutations could be a risk factor for developing PD. Parkin gene mutation testing was performed in young onset PD (diagnosed <50 years old) to identify three groups: Parkin homozygous or compound heterozygote mutation carriers, Parkin single heterozygote mutation carriers, and non-carriers of Parkin mutations. Olfaction was tested using the 40-item British version of the University of Pennsylvania smell identification test (UPSIT). Of 344 young onset PD cases tested, 8 (2.3%) were Parkin compound heterozygotes and 13 (3.8%) were Parkin single heterozygotes. Olfaction results were available in 282 cases (eight compound heterozygotes, nine single heterozygotes, and 265 non-carriers). In Parkin compound heterozygotes, the median UPSIT score was 33, interquartile range (IQR) 28.5-36.5, which was significantly better than in single Parkin heterozygotes (median 19, IQR 18-28) and non-carriers (median score 22, IQR 16-28) (ANOVA P < 0.001). These differences persisted after adjusting for age, disease duration, gender, and smoking (P < 0.001). There was no significant difference in UPSIT scores between single heterozygotes and non-carriers (P = 0.90). Patients with Parkin compound heterozygous mutations have relatively preserved olfaction compared to Parkin single heterozygotes and non-carriers. The prevalence of Parkin single heterozygosity is similar to the 3.7% rate reported in healthy controls. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Magnetic Nanoparticle Drug Carriers and their Study by Quadrupole Magnetic Field-Flow Fractionation

PubMed Central

Williams, P. Stephen; Carpino, Francesca; Zborowski, Maciej

2009-01-01

Magnetic nanoparticle drug carriers continue to attract considerable interest for drug targeting in the treatment of cancers and other pathological conditions. The efficient delivery of therapeutic levels of drug to a target site while limiting nonspecific, systemic toxicity requires optimization of the drug delivery materials, the applied magnetic field, and the treatment protocol. The history and current state of magnetic drug targeting is reviewed. While initial studies involved micron-sized and larger carriers, and work with these microcarriers continues, it is the sub-micron carriers or nanocarriers that are of increasing interest. An aspect of magnetic drug targeting using nanoparticle carriers that has not been considered is then addressed. This aspect involves the variation in the magnetic properties of the nanocarriers. Quadrupole magnetic field-flow fractionation (QMgFFF) is a relatively new technique for characterizing magnetic nanoparticles. It is unique in its capability of determining the distribution in magnetic properties of a nanoparticle sample in suspension. The development and current state of this technique is also reviewed. Magnetic nanoparticle drug carriers have been found by QMgFFF analysis to be highly polydisperse in their magnetic properties, and the strength of response of the particles to magnetic field gradients is predicted to vary by orders of magnitude. It is expected that the least magnetic fraction of a formulation will contribute the most to systemic toxicity, and the depletion of this fraction will result in a more effective drug carrying material. A material that has a reduced systemic toxicity will allow higher doses of cytotoxic drugs to be delivered to the tumor with reduced side effects. Preliminary experiments involving a novel method of refining a magnetic nanoparticle drug carrier to achieve this result are described. QMgFFF is used to characterize the refined and unrefined material. PMID:19591456

Stepwise verification of bone regeneration using recombinant human bone morphogenetic protein-2 in rat fibula model

PubMed Central

2017-01-01

Objectives The purpose of this study was to introduce our three experiments on bone morphogenetic protein (BMP) and its carriers performed using the critical sized segmental defect (CSD) model in rat fibula and to investigate development of animal models and carriers for more effective bone regeneration. Materials and Methods For the experiments, 14, 16, and 24 rats with CSDs on both fibulae were used in Experiments 1, 2, and 3, respectively. BMP-2 with absorbable collagen sponge (ACS) (Experiments 1 and 2), autoclaved autogenous bone (AAB) and fibrin glue (FG) (Experiment 3), and xenogenic bone (Experiment 2) were used in the experimental groups. Radiographic and histomorphological evaluations were performed during the follow-up period of each experiment. Results Significant new bone formation was commonly observed in all experimental groups using BMP-2 compared to control and xenograft (porcine bone) groups. Although there was some difference based on BMP carrier, regenerated bone volume was typically reduced by remodeling after initially forming excessive bone. Conclusion BMP-2 demonstrates excellent ability for bone regeneration because of its osteoinductivity, but efficacy can be significantly different depending on its delivery system. ACS and FG showed relatively good bone regeneration capacity, satisfying the essential conditions of localization and release-control when used as BMP carriers. AAB could not provide release-control as a BMP carrier, but its space-maintenance role was remarkable. Carriers and scaffolds that can provide sufficient support to the BMP/carrier complex are necessary for large bone defects, and AAB is thought to be able to act as an effective scaffold. The CSD model of rat fibula is simple and useful for initial estimate of bone regeneration by agents including BMPs. PMID:29333367

Development of mass production type rigid polyurethane foam for LNG carrier using ozone depletion free blowing agent

NASA Astrophysics Data System (ADS)

Lee, Yeongbeom; Baek, Kye Hyun; Choe, Kunhyung; Han, Chonghun

2016-12-01

Nowadays the price of natural gas has become higher and the efficiency of propulsion system of liquefied natural gas (LNG) carriers has improved. Due to these trends, required boil-off rate (BOR) for LNG carrier has been lowered from 0.15%/day to 0.12%/day for conventional LNG carriers with sizes between 125,000 m3 and 170,000 m3. This requirement of BOR can be satisfied by using a rigid polyurethane foam (PUF) blown by 1,1-dichloro-1-fluoroethane (HCFC-141b) as an insulator. However, ozone depletion potential (ODP) of HCFC-141b requires alternative blowing agents with zero ODP such as hydroflurocarbons (HFCs) because of tougher environmental regulations. This paper introduces use of HFCs and additives to enhance properties of rigid PUFs under a mass production environment. Among the additives, perfluoroalkane (PFA) reduces thermal conductivity down to 12% and increases compressive strength up to 15% of a rigid PUF prepared in a laboratory scale. Based on this result, a mass production type rigid PUF is manufactured and is evaluated for BOR, mechanical strengths over operation temperature range, and thermal shock stability for LNG carriers. The BOR of the manufactured rigid PUF is below 0.12%/day, which satisfies the recent BOR specification for LNG carriers. The other required properties are also met the specifications for a conventional LNG carrier. Consequently, it is expected that the results in this paper will bring low BOR (<0.12%/day) LNG carries with rigid PUFs using ODP free blowing agents and contribute environmental protection through saving energy and preserving the ozone layer in the stratosphere.

A Multi-Cohort Study of ApoE ɛ4 and Amyloid-β Effects on the Hippocampus in Alzheimer’s Disease

PubMed Central

Khan, Wasim; Giampietro, Vincent; Banaschewski, Tobias; Barker, Gareth J.; Bokde, Arun L.W.; Büchel, Christian; Conrod, Patricia; Flor, Herta; Frouin, Vincent; Garavan, Hugh; Gowland, Penny; Heinz, Anreas; Ittermann, Bernd; Lemaître, Hervé; Nees, Frauke; Paus, Tomas; Pausova, Zdenka; Rietschel, Marcella; Smolka, Michael N.; Ströhle, Andreas; Gallinat, Jeurgen; Vellas, Bruno; Soininen, Hilkka; Kloszewska, Iwona; Tsolaki, Magda; Mecocci, Patrizia; Spenger, Christian; Villemagne, Victor L.; Masters, Colin L.; Muehlboeck, J-Sebastian; Bäckman, Lars; Fratiglioni, Laura; Kalpouzos, Grégoria; Wahlund, Lars-Olof; Schumann, Gunther; Lovestone, Simon; Williams, Steven C.R.; Westman, Eric; Simmons, Andrew

2017-01-01

The apolipoprotein E (APOE) gene has been consistently shown to modulate the risk of Alzheimer’s disease (AD). Here, using an AD and normal aging dataset primarily consisting of three AD multi-center studies (n = 1,781), we compared the effect of APOE and amyloid-β (Aβ) on baseline hippocampal volumes in AD patients, mild cognitive impairment (MCI) subjects, and healthy controls. A large sample of healthy adolescents (n = 1,387) was also used to compare hippocampal volumes between APOE groups. Subjects had undergone a magnetic resonance imaging (MRI) scan and APOE genotyping. Hippocampal volumes were processed using FreeSurfer. In the AD and normal aging dataset, hippocampal comparisons were performed in each APOE group and in ɛ4 carriers with positron emission tomography (PET) Aβ who were dichotomized (Aβ+/Aβ–) using previous cut-offs. We found a linear reduction in hippocampal volumes with ɛ4 carriers possessing the smallest volumes, ɛ3 carriers possessing intermediate volumes, and ɛ2 carriers possessing the largest volumes. Moreover, AD and MCI ɛ4 carriers possessed the smallest hippocampal volumes and control ɛ2 carriers possessed the largest hippocampal volumes. Subjects with both APOE ɛ4 and Aβ positivity had the lowest hippocampal volumes when compared to Aβ- ɛ4 carriers, suggesting a synergistic relationship between APOE ɛ4 and Aβ. However, we found no hippocampal volume differences between APOE groups in healthy 14-year-old adolescents. Our findings suggest that the strongest neuroanatomic effect of APOE ɛ4 on the hippocampus is observed in AD and groups most at risk of developing the disease, whereas hippocampi of old and young healthy individuals remain unaffected. PMID:28157104

Ultrafast carrier dynamics in organic molecular crystals and conjugated polymers

NASA Astrophysics Data System (ADS)

Hegmann, Frank

2005-03-01

Organic semiconductors are being extensively studied by many research groups around the world for applications in electronic and photonic devices. For example, much work has focused on the development of organic thin film transistors based on thermally evaporated pentacene films, where the polycrystalline morphology typically results in a thermally-activated carrier mobility. On the other hand, more intrinsic bandlike transport, where the carrier mobility increases as the temperature decreases, has been observed in many organic single crystals. However, the nature of charge transport in organic molecular crystals is still not understood. Also, despite many advances in organic photonics, the nature of photocarrier generation in organic semiconductors is not completely understood and remains controversial even today. The generation of mobile charge carriers in photoexcited organic materials occurs over femtosecond to picosecond time scales, and so ultrafast pump-probe experiments are essential in order to improve our understanding of fundamental processes in these materials. Recently, time-resolved terahertz pulse spectroscopy has been used to directly probe transient photoconductivity in pentacene and functionalized pentacene thin films and single crystals [1,2], revealing photogeneration of mobile charge carriers over sub-picosecond time scales as well as bandlike carrier transport in both single crystal and thin film samples [1]. This talk will provide an overview of ultrafast carrier dynamics in organic semiconductors, and will emphasize how time-resolved terahertz pulse spectroscopy can be used to help understand the nature of photoexcitations and carrier transport in organic materials. (This work was supported by NSERC, CFI, CIPI, the Killam Trust, and ONR. Collaborators for this work are listed in Ref. 1.) [1] O. Ostroverkhova, D. G. Cooke, S. Shcherbyna, R. F. Egerton, F. A. Hegmann, R. R. Tykwinski, and J. E. Anthony, Phys. Rev. B., in press. [2] V. K. Thorsmølle, R. D. Averitt, X. Chi, D. J. Hilton, D. L. Smith, A. P. Ramirez, and A. J. Taylor, Appl. Phys. Lett. 84, 891 (2004).

Gynecologic surgeries and risk of ovarian cancer in women with BRCA1 and BRCA2 Ashkenazi founder mutations: an Israeli population-based case-control study.

PubMed

Rutter, Joni L; Wacholder, Sholom; Chetrit, Angela; Lubin, Flora; Menczer, Joseph; Ebbers, Sarah; Tucker, Margaret A; Struewing, Jeffery P; Hartge, Patricia

2003-07-16

In the general population, the risk of developing ovarian cancer is reduced in women who have undergone tubal ligation, hysterectomy, or oophorectomy, although peritoneal cancer can arise after bilateral oophorectomy. In studies from genetic screening clinics, women with mutations in the breast and ovarian susceptibility genes BRCA1 and BRCA2 have been found to have a low risk of peritoneal carcinoma in the first years after bilateral oophorectomy. We assessed the level and persistence of reduction of ovarian (including peritoneal) cancer risk after gynecologic surgeries for women who carry BRCA1/2 mutations but were not selected from high-risk clinics. We identified 1124 Israeli women with incident ovarian cancer or primary peritoneal cancer and tested 847 of them for the three Ashkenazi founder mutations. We compared gynecologic surgery history among all case patients, BRCA1 (n = 187) and BRCA2 (n = 64) carrier case patients, and the non-carrier case patients (n = 598) with that in control subjects drawn from a population registry (n = 2396). We estimated ovarian cancer risk (odds ratios [ORs] with 95% confidence intervals [CIs]) after gynecologic surgery in mutation carriers and non-carriers with logistic regression models. Eight women with primary peritoneal cancer and 128 control subjects reported a previous bilateral oophorectomy (OR = 0.12, 95% CI = 0.06 to 0.24). Other gynecologic surgeries were associated with a 30%-50% reduced risk of ovarian cancer, depending on the type of surgery, with surgery to remove some ovarian tissue associated with the most risk reduction (OR = 0.34, 95% CI = 0.16 to 0.74). Reduced risks were seen in BRCA1/2 carriers and non-carriers. Age at surgery and years since surgery did not affect risk reductions. Both BRCA1/2 mutation carriers and non-carriers have reduced risk of ovarian or peritoneal cancer after gynecologic surgery. The magnitude of the reduction depends upon the type and extent of surgery.

Carriers of the hypertrophic cardiomyopathy MYBPC3 mutation are characterized by reduced myocardial efficiency in the absence of hypertrophy and microvascular dysfunction.

PubMed

Timmer, Stefan A J; Germans, Tjeerd; Brouwer, Wessel P; Lubberink, Mark; van der Velden, Jolanda; Wilde, Arthur A M; Christiaans, Imke; Lammertsma, Adriaan A; Knaapen, Paul; van Rossum, Albert C

2011-12-01

Next to left ventricular (LV) hypertrophy, hypertrophic cardiomyopathy (HCM) is characterized by microvascular dysfunction and reduced myocardial external efficiency (MEE). Insights into the presence of these abnormalities as early markers of disease are of clinical importance in risk stratification, and development of therapeutic approaches. Therefore, the aim was to investigate myocardial perfusion and energetics in genotype-positive, phenotype-negative HCM subjects (carriers). Fifteen carriers of an MYBPC3 mutation underwent [(15)O]water positron emission tomography (PET) to assess myocardial blood flow (MBF). [(11)C]acetate PET was performed to obtain myocardial oxygen consumption (MVO(2)). By use of cardiovascular magnetic resonance imaging, LV volumes and mass were defined to calculate MEE, i.e. the ratio between external work and MVO(2). Eleven healthy, genotype-negative, family relatives underwent similar scanning protocols to serve as a control group. Left ventricular mass was comparable between carriers and controls (93 ± 25 vs. 99 ± 21 g, P= 0.85), as was MBF at rest (1.19 ± 0.34 vs. 1.18 ± 0.32 mL min(-1) g(-1), P= 0.92), and during hyperaemia (3.87 ± 0.75 vs. 3.96 ± 0.86 mL min(-1) g(-1), P= 0.77). Myocardial oxygen consumption averaged 0.137 ± 0.057 mL min(-1) g(-1) in carriers and was not significantly different from controls (0.125 ± 0.043 mL min(-1) g(-1), P= 0.29). Cardiac work, however, was slightly reduced in carriers (7398 ± 1384 vs. 9139 ± 2484 mmHg mL in controls, P= 0.08). As a consequence, MEE was significantly decreased in carriers (27 ± 10 vs. 36 ± 8% in controls, P= 0.02). Carriers display reduced myocardial work generation in relation to oxygen consumption, in the absence of hypertrophy and flow abnormalities. Hence, impaired myocardial energetics may constitute a primary component of HCM pathogenesis.

Separation of intron 22 inversion type 1 and 2 of hemophilia A by modified inverse-shifting polymerase chain reaction and capillary gel electrophoresis.

PubMed

Pan, Tzu-Yu; Chiou, Shyh-Shin; Wang, Chun-Chi; Wu, Shou-Mei

2014-12-01

An inverse-shifting polymerase chain reaction (IS-PCR) combined with short-end capillary gel electrophoresis (CGE) was developed for genotyping of intron 22 inversion Type 1 (Inv22-1) and Type 2 (Inv22-2) of hemophilia A (HA). Severe HA cases are affected by intron 22 inversion around 45-50%. Inv22-1 has higher frequency than Inv22-2. The aim of this study is to distinguish them by genotyping. In order to improve Inv22 genotyping efficiency, five primers were designed and applied to differentiate the wild type, Inv22-1, Inv22-2 and carrier. Three amplicons of 405, 457 and 512 bp were recognized for wild type; 333, 457 and 584 bp for Inv22-1; 385, 405 and 584 bp for Inv22-2. The Inv22-1 carrier has 5 amplicons including 333, 405, 457, 512, 584 bp and Inv22-2 carrier is differentiated by 385, 405, 457, 512 and 584 bp. The amplicons between Inv22-1 and Inv22-2 carriers are only different in 333 bp for Inv22-1 carrier and 385 bp for Inv22-2 carrier. Capillary gel electrophoresis (CGE) was used for separation within 5 min. The separation voltage was set at 8 kV (cathode at detector), and the temperature was kept at 25°C. The sieving matrix was 89 mM Tris, 89 mM boric acid, 2mM EDTA containing 0.4% (w/v) HPMC and 1 μM of YO-PRO(®)-1 Iodide. Total of 50 HA patients (including 35 non-Inv22, 14 Inv22-1, and one Inv22-2 patients) and 7 HA carriers were diagnosed in the application. Seven random samples (5 patients and 2 carriers) were subjected to comparison and gave identical results of DNA sequencing and this modified IS-PCR. Copyright © 2014 Elsevier B.V. All rights reserved.

Development of a Thermal Isolation Structure for Aerospace Cryogenic Instruments

NASA Technical Reports Server (NTRS)

Nash, A.; Robeck, L.

1999-01-01

A proof of concept prototype cryostat has been developed to demonstrate the ability to accommodate low temperature science investigations within the constraints of the Hitchhiker siderail carrier on the space shuttle.

High‐Volume Processed, ITO‐Free Superstrates and Substrates for Roll‐to‐Roll Development of Organic Electronics

PubMed Central

Hösel, Markus; Angmo, Dechan; Søndergaard, Roar R.; dos Reis Benatto, Gisele A.; Carlé, Jon E.; Jørgensen, Mikkel

2014-01-01

The fabrication of substrates and superstrates prepared by scalable roll‐to‐roll methods is reviewed. The substrates and superstrates that act as the flexible carrier for the processing of functional organic electronic devices are an essential component, and proposals are made about how the general availability of various forms of these materials is needed to accelerate the development of the field of organic electronics. The initial development of the replacement of indium‐tin‐oxide (ITO) for the flexible carrier materials is described and a description of how roll‐to‐roll processing development led to simplification from an initially complex make‐up to higher performing materials through a more simple process is also presented. This process intensification through process simplification is viewed as a central strategy for upscaling, increasing throughput, performance, and cost reduction. PMID:27980893

The Block V Receiver fast acquisition algorithm for the Galileo S-band mission

NASA Technical Reports Server (NTRS)

Aung, M.; Hurd, W. J.; Buu, C. M.; Berner, J. B.; Stephens, S. A.; Gevargiz, J. M.

1994-01-01

A fast acquisition algorithm for the Galileo suppressed carrier, subcarrier, and data symbol signals under low data rate, signal-to-noise ratio (SNR) and high carrier phase-noise conditions has been developed. The algorithm employs a two-arm fast Fourier transform (FFT) method utilizing both the in-phase and quadrature-phase channels of the carrier. The use of both channels results in an improved SNR in the FFT acquisition, enabling the use of a shorter FFT period over which the carrier instability is expected to be less significant. The use of a two-arm FFT also enables subcarrier and symbol acquisition before carrier acquisition. With the subcarrier and symbol loops locked first, the carrier can be acquired from an even shorter FFT period. Two-arm tracking loops are employed to lock the subcarrier and symbol loops parameter modification to achieve the final (high) loop SNR in the shortest time possible. The fast acquisition algorithm is implemented in the Block V Receiver (BVR). This article describes the complete algorithm design, the extensive computer simulation work done for verification of the design and the analysis, implementation issues in the BVR, and the acquisition times of the algorithm. In the expected case of the Galileo spacecraft at Jupiter orbit insertion PD/No equals 14.6 dB-Hz, R(sym) equals 16 symbols per sec, and the predicted acquisition time of the algorithm (to attain a 0.2-dB degradation from each loop to the output symbol SNR) is 38 sec.

A new technology for harnessing the dye polluted water and dye collection in a chemical factory.

PubMed

Pu, J P; Pu, P M; Hu, C H; Qian, J L; Pu, J X; Hua, J K

2001-04-01

A new technology for harnessing the dye polluted water and dye collection was developed. It is based on the enhanced evaporation by using solar, wind and air temperature energy and additional heat-electric energy. It consists of four parts: (1) evaporation carrier system (evaporation carrier and frame for evaporation carrier) for polluted water; (2) polluted water circulating system (pumping-spraying-collecting); (3) heating system; (4) workshop with polluted water reservoir-tanks and rainfall prevention roof. The polluted water was (heated in case necessary) sprayed to the evaporation carrier system and the water was evaporated when it moved in the space and downward along the carrier mainly by using natural (solar, wind and air temperature energy). In case, when there is no roof for the carrier system, the polluted water can be stored in the reservoirs (storage volume for about 20 days). The first 10-25 mm rainfall also need to be stored in the reservoirs to meet the state standard for discharging wastewater. The dye may be collected at the surface in the reservoir-tanks and the crystallized salt may be collected at the bottom plate. The black-color wastewater released by the factory is no more discharged to the surface water system of Taihu Lake Basin. About 2 kg dye and 200 kg industrial salt may be collected from each tone of the polluted water. The non-pollution production of dye may be realized by using this technology with environmental, economical and social benefits.

Meso and micro-scale response of post carbon removal nitrifying MBBR biofilm across carrier type and loading.

PubMed

Young, Bradley; Banihashemi, Bahman; Forrest, Daina; Kennedy, Kevin; Stintzi, Alain; Delatolla, Robert

2016-03-15

This study investigates the effects of three specific moving bed biofilm reactor (MBBR) carrier types and two surface area loading rates on biofilm thickness, morphology and bacterial community structure of post carbon removal nitrifying MBBR systems along with the effects of carrier type and loading on ammonia removal rates and effluent solids settleability. The meso and micro analyses show that the AOB kinetics vary based on loading condition, but irrespective of carrier type. The meso-scale response to increases in loading was shown to be an increase in biofilm thickness with higher surface area carriers being more inclined to develop and maintain thicker biofilms. The pore spaces of these higher surface area to volume carriers also demonstrated the potential to become clogged at higher loading conditions. Although the biofilm thickness increased during higher loading conditions, the relative percentages of both the embedded viable and non-viable cells at high and conventional loading conditions remained stable; indicating that the reduced ammonia removal kinetics observed during carrier clogging events is likely due to the observed reduction in the surface area of the attached biofilm. Microbial community analyses demonstrated that the dominant ammonia oxidizing bacteria for all carriers is Nitrosomonas while the dominant nitrite oxidizing bacteria is Nitrospira. The research showed that filamentous species were abundant under high loading conditions, which likely resulted in the observed reduction in effluent solids settleability at high loading conditions as opposed to conventional loading conditions. Although the settleability of the effluent solids was correlated to increases in abundances of filamentous organisms in the biofilm, analyzed using next generation sequencing, the ammonia removal rate was not shown to be directly correlated to specific meso or micro-scale characteristics. Instead post carbon removal MBBR ammonia removal kinetics were shown to be related to the viable AOB cell coverage of the carriers; which was calculated by normalizing the surface area removal rate by the biofilm thickness, the bacterial percent abundance of ammonia oxidizing bacteria and the percentage of viable cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gallic acid grafting effect on delivery performance and antiglaucoma efficacy of antioxidant-functionalized intracameral pilocarpine carriers.

PubMed

Chou, Shih-Feng; Luo, Li-Jyuan; Lai, Jui-Yang

2016-07-01

Functionalization of therapeutic carrier biomaterials can potentially provide additional benefits in drug delivery for disease treatment. Given that this modification determines final therapeutic efficacy of drug carriers, here, we investigate systematically the role of grafting amount of antioxidant gallic acid (GA) onto GN in situ gelling copolymers made of biodegradable gelatin and thermo-responsive poly(N-isopropylacrylamide) for intracameral delivery of pilocarpine in antiglaucoma treatment. As expected, increasing redox reaction time increased total antioxidant activities and free radical scavenging abilities of synthesized carrier biomaterials. The hydrophilic nature of antioxidant molecules strongly affected physicochemical properties of carrier materials with varying GA grafting amounts, thereby dictating in vitro release behaviors and mechanisms of pilocarpine. In vitro oxidative stress challenges revealed that biocompatible carriers with high GA content alleviated lens epithelial cell damage and reduced reactive oxygen species. Intraocular pressure and pupil diameter in glaucomatous rabbits showed correlations with GA-mediated release of pilocarpine. Additionally, enhanced pharmacological treatment effects prevented corneal endothelial cell loss during disease progression. Increasing GA content increased total antioxidant level and decreased nitrite level in the aqueous humor, suggesting a much improved antioxidant status in glaucomatous eyes. This work significantly highlights the dependence of physicochemical properties, drug release behaviors, and bioactivities on intrinsic antioxidant capacities of therapeutic carrier biomaterials for glaucoma treatment. Development of injectable biodegradable polymer depots and functionalization of carrier biomaterials with antioxidant can potentially provide benefits such as improved bioavailability, controlled release pattern, and increased therapeutic effect in intracameral pilocarpine administration for glaucoma treatment. For the first time, this study demonstrated that the biodegradable in situ gelling copolymers can incorporate different levels of antioxidant gallic acid to tailor the structure-property-function relationship of the intracameral drug delivery system. The systematic evaluation fully verified the dependence of phase transition, degradation behavior, drug release mechanism, and antiglaucoma efficacy on intrinsic antioxidant capacities of carrier biomaterials. The report highlights the significant role of grafting amount of gallic acid in optimizing performance of antioxidant-functionalized polymer therapeutics as new drug delivery platforms in disease treatment. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Assessing the Deterrence Value of Carrier Presence Against Adversary Aggression in a Coalition Environment

DTIC Science & Technology

2017-09-01

seeks to quantify the deterrence value of a CSG using a game - theoretic framework. Consider a region with several nations, where two major players stand...develop a Markov game to model the interactions between the two players and these other nations over a period of time. The game starts in Notional...establishing diplomatic advantage are equally important in deterring aggression. 14. SUBJECT TERMS carrier strike group, CSG, deterrence, Markov game

Development of a Telemetry-Enabled High-G Projectile Carrier

DTIC Science & Technology

2012-09-01

of High Velocity Guns, Version 2 (IBHVG2) interior ballistics simulation • Pete Muller, ARL, helped populate the ARL sensor suite boards...differences in external characteristics between the conventional M831 and the modified M831 high-g carrier projectile can be seen in figure 3. Figure 2...of High Velocity Guns, Version 2 (IBHVG2) (6). The output values from the simulation for the selected charge weight are seen in table 2. Table 2

InAs1-xSbx Alloys with Native Llattice Parameters Grown on Compositionally Graded Buffers: Structural and Optical Properties

DTIC Science & Technology

2013-08-15

InAsSb, compositionally graded buffer, MBE, infrared, minority carrier lifetime, reciprocal space mapping Ding Wang, Dmitry Donetsky, Youxi Lin, Gela...infrared, minority carrier lifetime; reciprocal space mapping . Introduction GaSb based Ill-Y materials are widely used in the development of mid... space mapping (RSM) at the symmetric (004) and asymmetric (335) Bragg reflections. Figure 3 presents a set of RSM measurements for a structure

Optimization of gas chromatographic method for the enantioseparation of arylpropionic non-steroidal anti-inflammatory drug methyl esters.

PubMed

Petrović, Marinko; Debeljak, Zeljko; Blazević, Nikola

2005-09-15

The gas chromatography (GC) method for enantioseparation of well-known non-steroidal anti-inflammatory drugs ibuprofen, fenoprofen and ketoprofen methyl esters mixture was developed. Best enantioseparation was performed on capillary column with heptakis-(2,3-di-O-methyl-6-O-t-butyldimethyl-silyl)-beta-cyclodextrin stationary phase and hydrogen used as a carrier gas. Initial temperature, program rate and carrier pressure were optimized to obtain best resolution between enantiomers.

Modal Analysis of Space-rocket Equipment Components

NASA Astrophysics Data System (ADS)

Igolkin, A. A.; Safin, A. I.; Prokofiev, A. B.

2018-01-01

In order to prevent vibration damage an analysis of natural frequencies and mode shapes of elements of rocket and space technology should be developed. This paper discusses technique of modal analysis on the example of the carrier platform. Modal analysis was performed by using mathematical modeling and laser vibrometer. Experimental data was clarified by using Test.Lab software. As a result of modal analysis amplitude-frequency response of carrier platform was obtained and the parameters of the elasticity was clarified.

One-step synthesis of gene carrier via gamma irradiation and its application in tumor gene therapy

PubMed Central

Kim, Eun-Ji; Heo, Hun; Park, Jong-Seok; Gwon, Hui-Jeong; Lim, Youn-Mook; Jang, Mi-Kyeong

2018-01-01

Introduction Although numerous studies have been conducted with the aim of developing drug-delivery systems, chemically synthesized gene carriers have shown limited applications in the biomedical fields due to several problems, such as low-grafting yields, undesirable reactions, difficulties in controlling the reactions, and high-cost production owing to multi-step manufacturing processes. Materials and methods We developed a 1-step synthesis process to produce 2-aminoethyl methacrylate-grafted water-soluble chitosan (AEMA-g-WSC) as a gene carrier, using gamma irradiation for simultaneous synthesis and sterilization, but no catalysts or photoinitiators. We analyzed the AEMA graft site on WSC using 2-dimensional nuclear magnetic resonance spectroscopy (2D NMR; 1H and 13C NMR), and assayed gene transfection effects in vitro and in vivo. Results We revealed selective grafting of AEMA onto C6-OH groups of WSC. AEMA-g-WSC effectively condensed plasmid DNA to form polyplexes in the size range of 170 to 282 nm. AEMA-g-WSC polyplexes in combination with psi-hBCL2 (a vector expressing short hairpin RNA against BCL2 mRNA) inhibited tumor cell proliferation and tumor growth in vitro and in vivo, respectively, by inducing apoptosis. Conclusion The simple grafting process mediated via gamma irradiation is a promising method for synthesizing gene carriers. PMID:29416333

Solid dispersion of poorly water-soluble drugs: early promises, subsequent problems, and recent breakthroughs.

PubMed

Serajuddin, A T

1999-10-01

Although there was a great interest in solid dispersion systems during the past four decades to increase dissolution rate and bioavailability of poorly water-soluble drugs, their commercial use has been very limited, primarily because of manufacturing difficulties and stability problems. Solid dispersions of drugs were generally produced by melt or solvent evaporation methods. The materials, which were usually semisolid and waxy in nature, were hardened by cooling to very low temperatures. They were then pulverized, sieved, mixed with relatively large amounts of excipients, and encapsulated into hard gelatin capsules or compressed into tablets. These operations were difficult to scale up for the manufacture of dosage forms. The situation has, however, been changing in recent years because of the availability of surface-active and self-emulsifying carriers and the development of technologies to encapsulate solid dispersions directly into hard gelatin capsules as melts. Solid plugs are formed inside the capsules when the melts are cooled to room temperature. Because of surface activity of carriers used, complete dissolution of drug from such solid dispersions can be obtained without the need for pulverization, sieving, mixing with excipients, etc. Equipment is available for large-scale manufacturing of such capsules. Some practical limitations of dosage form development might be the inadequate solubility of drugs in carriers and the instability of drugs and carriers at elevated temperatures necessary to manufacture capsules.

Concise review: Nanoparticles and cellular carriers-allies in cancer imaging and cellular gene therapy?

PubMed Central

Tang, Catherine; Russell, Pamela J; Martiniello-Wilks, Rosetta; J Rasko, John E; Khatri, Aparajita

2010-01-01

Ineffective treatment and poor patient management continue to plague the arena of clinical oncology. The crucial issues include inadequate treatment efficacy due to ineffective targeting of cancer deposits, systemic toxicities, suboptimal cancer detection and disease monitoring. This has led to the quest for clinically relevant, innovative multifaceted solutions such as development of targeted and traceable therapies. Mesenchymal stem cells (MSCs) have the intrinsic ability to “home” to growing tumors and are hypoimmunogenic. Therefore, these can be used as (a) “Trojan Horses” to deliver gene therapy directly into the tumors and (b) carriers of nanoparticles to allow cell tracking and simultaneous cancer detection. The camouflage of MSC carriers can potentially tackle the issues of safety, vector, and/or transgene immunogenicity as well as nanoparticle clearance and toxicity. The versatility of the nanotechnology platform could allow cellular tracking using single or multimodal imaging modalities. Toward that end, noninvasive magnetic resonance imaging (MRI) is fast becoming a clinical favorite, though there is scope for improvement in its accuracy and sensitivity. In that, use of superparamagnetic iron-oxide nanoparticles (SPION) as MRI contrast enhancers may be the best option for tracking therapeutic MSC. The prospects and consequences of synergistic approaches using MSC carriers, gene therapy, and SPION in developing cancer diagnostics and therapeutics are discussed. STEM CELLS 2010; 28:1686–1702. PMID:20629172

Defining the cause of skewed X-chromosome inactivation in X-linked mental retardation by use of a mouse model.

PubMed

Muers, Mary R; Sharpe, Jacqueline A; Garrick, David; Sloane-Stanley, Jacqueline; Nolan, Patrick M; Hacker, Terry; Wood, William G; Higgs, Douglas R; Gibbons, Richard J

2007-06-01

Extreme skewing of X-chromosome inactivation (XCI) is rare in the normal female population but is observed frequently in carriers of some X-linked mutations. Recently, it has been shown that various forms of X-linked mental retardation (XLMR) have a strong association with skewed XCI in female carriers, but the mechanisms underlying this skewing are unknown. ATR-X syndrome, caused by mutations in a ubiquitously expressed, chromatin-associated protein, provides a clear example of XLMR in which phenotypically normal female carriers virtually all have highly skewed XCI biased against the X chromosome that harbors the mutant allele. Here, we have used a mouse model to understand the processes causing skewed XCI. In female mice heterozygous for a null Atrx allele, we found that XCI is balanced early in embryogenesis but becomes skewed over the course of development, because of selection favoring cells expressing the wild-type Atrx allele. Unexpectedly, selection does not appear to be the result of general cellular-viability defects in Atrx-deficient cells, since it is restricted to specific stages of development and is not ongoing throughout the life of the animal. Instead, there is evidence that selection results from independent tissue-specific effects. This illustrates an important mechanism by which skewed XCI may occur in carriers of XLMR and provides insight into the normal role of ATRX in regulating cell fate.

Minoxidil-loaded nanostructured lipid carriers (NLC): characterization and rheological behaviour of topical formulations.

PubMed

Silva, A C; Santos, D; Ferreira, D C; Souto, E B

2009-03-01

Lipid nanoparticles are used as biocompatible carriers for several types of drugs intended for pharmaceutical, cosmetic, and biochemical purposes. The wide range of lipids and surfactants available for the production of such particles turns these carriers highly suitable for distinct applications (topical, dermal and transdermal, parenteral, pulmonary, and oral administration). This work describes the development of a special type of lipid particles, namely nanostructured lipid carriers (NLC), for minoxidil as an alternative to conventional topical alcoholic solutions. NLC were composed of stearic acid and oleic acid, being the matrix stabilized with poloxamer 188 in aqueous dispersion. To develop a suitable topical formulation, lipid dispersions were further mixed with freshly prepared Carbopol or perfluorocarbon based hydrogels. Minoxidil-loaded NLC were approximately 250 nm in size before the entrapment within the gel network and remained below 500 nm after mixing with both types of hydrogels. The occurrence of minoxidil crystallization in the aqueous phase of lipid dispersions was discarded under analysis by light microscopy and by scanning electron microscopy. Differential scanning calorimetry was used to assess the recrystallization index (i.e. measure of the percentage of lipid matrix that is crystallized) of the particles, which was shown to be 62% for minoxidil-free dispersions and 68% for minoxidil-loaded NLC dispersions. Rheological analysis of hydrogels containing NLC dispersions showed typical pseudoplastic behaviour which makes them suitable for topical purposes.

Creation of a National, At-home Model for Ashkenazi Jewish Carrier Screening.

PubMed

Grinzaid, Karen Arnovitz; Page, Patricia Zartman; Denton, Jessica Johnson; Ginsberg, Jessica

2015-06-01

Ethnicity-based carrier screening for the Ashkenazi Jewish population has been available and encouraged by advocacy and community groups since the early 1970's. Both the American College of Medical Genetics and the American Congress of Obstetricians and Gynecologists recommend carrier screening for this population (Obstetrics and Gynecology, 114(4), 950-953, 2009; Genetics in Medicine, 10(1), 55-56, 2008). While many physicians inquire about ethnic background and offer appropriate carrier screening, studies show that a gap remains in implementing recommendations (Genetic testing and molecular biomarkers, 2011). In addition, education and outreach efforts targeting Jewish communities have had limited success in reaching this at-risk population. Despite efforts by the medical and Jewish communities, many Jews of reproductive age are not aware of screening, and remain at risk for having children with preventable diseases. Reaching this population, preferably pre-conception, and facilitating access to screening is critically important. To address this need, genetic counselors at Emory University developed JScreen, a national Jewish genetic disease screening program. The program includes a national marketing and PR campaign, online education, at-home saliva-based screening, post-test genetic counseling via telephone or secure video conferencing, and referrals for face-to-face genetic counseling as needed. Our goals are to create a successful education and screening program for this population and to develop a model that could potentially be used for other at-risk populations.

Thermal and Evolved Gas Analysis of Geologic Samples Containing Organic Materials: Implications for the 2007 Mars Phoenix Scout Mission

NASA Technical Reports Server (NTRS)

Lauer, H. V., Jr.; Ming, Douglas W.; Golden, D. C.; Boynton, W. V.

2006-01-01

The Thermal and Evolved Gas Analyzer (TEGA) instrument scheduled to fly onboard the 2007 Mars Phoenix Scout Mission will perform differential scanning calorimetry (DSC) and evolved gas analysis (EGA) of soil samples and ice collected from the surface and subsurface at a northern landing site on Mars. We have been developing a sample characterization data library using a laboratory DSC integrated with a quadrupole mass spectrometer to support the interpretations of TEGA data returned during the mission. The laboratory TEGA test-bed instrument has been modified to operate under conditions similar to TEGA, i.e., reduced pressure (e.g., 100 torr) and reduced carrier gas flow rates. We have previously developed a TEGA data library for a variety of volatile-bearing mineral phases, including Fe-oxyhydroxides, phyllosilicates, carbonates, and sulfates. Here we examine the thermal and evolved gas properties of samples that contain organics. One of the primary objectives of the Phoenix Scout Mission is to search for habitable zones by assessing organic or biologically interesting materials in icy soil. Nitrogen is currently the carrier gas that will be used for TEGA. In this study, we examine two possible modes of detecting organics in geologic samples; i.e., pyrolysis using N2 as the carrier gas and combustion using O2 as the carrier gas.

The effect of genotypes and parent of origin on cancer risk and age of cancer development in PMS2 mutation carriers.

PubMed

Suerink, Manon; van der Klift, Heleen M; Ten Broeke, Sanne W; Dekkers, Olaf M; Bernstein, Inge; Capellá Munar, Gabriel; Gomez Garcia, Encarna; Hoogerbrugge, Nicoline; Letteboer, Tom G W; Menko, Fred H; Lindblom, Annika; Mensenkamp, Arjen; Moller, Pal; van Os, Theo A; Rahner, Nils; Redeker, Bert J W; Olderode-Berends, M J W; Olderode, Maran; Spruijt, Liesbeth; Vos, Yvonne J; Wagner, Anja; Morreau, Hans; Hes, Frederik J; Vasen, Hans F A; Tops, Carli M; Wijnen, Juul T; Nielsen, Maartje

2016-04-01

Lynch syndrome (LS), a heritable disorder with an increased risk of primarily colorectal cancer (CRC) and endometrial cancer (EC), can be caused by mutations in the PMS2 gene. We wished to establish whether genotype and/or parent-of-origin effects (POE) explain (part of) the reported variability in severity of the phenotype. European PMS2 mutation carriers (n = 381) were grouped and compared based on RNA expression and whether the mutation was inherited paternally or maternally. Mutation carriers with loss of RNA expression (group 1) had a significantly lower age at CRC diagnosis (51.1 years vs. 60.0 years, P = 0.035) and a lower age at EC diagnosis (55.8 years vs. 61.0 years, P = 0.2, nonsignificant) compared with group 2 (retention of RNA expression). Furthermore, group 1 showed slightly higher, but nonsignificant, hazard ratios (HRs) for both CRC (HR: 1.31, P = 0.38) and EC (HR: 1.22, P = 0.72). No evidence for a significant parent-of-origin effect was found for either CRC or EC. PMS2 mutation carriers with retention of RNA expression developed CRC 9 years later than those with loss of RNA expression. If confirmed, this finding would justify a delay in surveillance for these cases. Cancer risk was not influenced by a parent-of-origin effect.Genet Med 18 4, 405-409.

Effects of intestinal colonization by Clostridium difficile and Staphylococcus aureus on microbiota diversity in healthy individuals in China.

PubMed

Dong, Danfeng; Ni, Qi; Wang, Chen; Zhang, Lihua; Li, Zhen; Jiang, Cen; EnqiangMao; Peng, Yibing

2018-05-03

Intestinal colonization by pathogenic bacteria is a risk factor for infection, and contributes to environmental contamination and disease dissemination. Alteration of gut microbiota also plays a pivotal role in the development of disease. Although Clostridium difficile and Staphylococcus aureus are well-recognized pathogens causing nosocomial and community infections, the intestinal colonization was not fully investigated. Herein, we explored their overall carriage rates in healthy adults from the community, and characterized the gut microbiomes of C. difficile and S. aureus carriers. Fecal samples were collected from 1709 healthy volunteers from communities in Shanghai, China, and tested for the presence of C. difficile, methicillin-sensitive S. aureus (MSSA), and methicillin-resistant S. aureus (MRSA) using culture-based techniques. To explore differences in the gut microbiome, 16S rRNA gene sequencing was conducted using samples from non-carriers (CH), C. difficile carriers (CCD), MRSA carriers (CM), and MSSA carriers (CS). Overall, we detected 12 C. difficile and 60 S. aureus isolates, accounting for 0.70% and 3.51% of total isolates, respectively. Eight isolates were determined to be MRSA, accounting for 13.3% of the S. aureus population. Sequencing data revealed that the microbial diversity and richness were similar among the four groups. However, at the phylum level, carriage of C. difficile or MRSA was associated with a paucity of Bacteroidetes and an overabundance of Proteobacteria compared with non-carriers. At the genus level, the prevalence of the genera Bacteroides, Prevotella, Faecalibacterium, and Roseburia was decreased in C. difficile-positive samples compared with the controls, while the proportion of Clostridium cluster XIVa species was increased. MRSA carriers exhibited a higher proportion of the genera Parasutterella and Klebsiella, but a decreased prevalence of Bacteroides. Compared with MSSA carriers, Klebsiella was the only genus found to be significantly enriched in MRSA carriers. In healthy adults, colonization by C. difficile or S. aureus did not significantly affect gut microbiota diversity. However, the alteration of the gut microbiota composition in C. difficile carriers could indicate a predisposition to further infection. Our study provides essential data on the prevalence and effects of C. difficile and S. aureus colonization on gut microbiota composition in healthy adults.

Ultrafast carrier thermalization and cooling dynamics in few-layer MoS2.

PubMed

Nie, Zhaogang; Long, Run; Sun, Linfeng; Huang, Chung-Che; Zhang, Jun; Xiong, Qihua; Hewak, Daniel W; Shen, Zexiang; Prezhdo, Oleg V; Loh, Zhi-Heng

2014-10-28

Femtosecond optical pump-probe spectroscopy with 10 fs visible pulses is employed to elucidate the ultrafast carrier dynamics of few-layer MoS2. A nonthermal carrier distribution is observed immediately following the photoexcitation of the A and B excitonic transitions by the ultrashort, broadband laser pulse. Carrier thermalization occurs within 20 fs and proceeds via both carrier-carrier and carrier-phonon scattering, as evidenced by the observed dependence of the thermalization time on the carrier density and the sample temperature. The n(-0.37 ± 0.03) scaling of the thermalization time with carrier density suggests that equilibration of the nonthermal carrier distribution occurs via non-Markovian quantum kinetics. Subsequent cooling of the hot Fermi-Dirac carrier distribution occurs on the ∼ 0.6 ps time scale via carrier-phonon scattering. Temperature- and fluence-dependence studies reveal the involvement of hot phonons in the carrier cooling process. Nonadiabatic ab initio molecular dynamics simulations, which predict carrier-carrier and carrier-phonon scattering time scales of 40 fs and 0.5 ps, respectively, lend support to the assignment of the observed carrier dynamics.

Residual and suppressed-carrier arraying techniques for deep-space communications

NASA Technical Reports Server (NTRS)

Shihabi, M.; Shah, B.; Hinedi, S.; Million, S.

1995-01-01

Three techniques that use carrier information from multiple antennas to enhance carrier acquisition and tracking are presented. These techniques in combination with baseband combining are analyzed and simulated for residual and suppressed-carrier modulation. It is shown that the carrier arraying using a single carrier loop technique can acquire and track the carrier even when any single antenna in the array cannot do so by itself. The carrier aiding and carrier arraying using multiple carrier loop techniques, on the other hand, are shown to lock on the carrier only when one of the array elements has sufficient margin to acquire the carrier on its own.

Micelle-like Nanoparticles as Carriers for DNA and siRNA

PubMed Central

Navarro, Gemma; Pan, Jiayi; Torchilin, Vladimir P.

2015-01-01

Gene therapy represents a potential efficient approach of disease prevention and therapy. However, due to their poor in vivo stability, gene molecules need to be associated with delivery systems to overcome extracellular and intracellular barriers and allow access to the site of action. Cationic polymeric nanoparticles are popular carriers for small interfering RNA (siRNA) and DNA-based therapeutics for which efficient and safe delivery are important factors that need to be optimized. Micelle-like nanoparticles (MNP) (half micelles, half polymeric nanoparticles) can overcome some of the disadvantages of such cationic carriers by unifying in one single carrier the best of both delivery systems. In this review, we will discuss how the unique properties of MNP including self-assembly, condensation and protection of nucleic acids, improved cell association and gene transfection, and low toxicity may contribute to the successful application of siRNA- and DNA-based therapeutics into the clinic. Recent developments of MNP involving the addition of stimulus-sensitive functions to respond specifically to pathological or externally applied “triggers” (e.g., temperature, pH or enzymatic catalysis, light, or magnetic fields) will be discussed. Finally, we will overview the use of MNP as two-in-one carriers for the simultaneous delivery of different agents (small molecules, imaging agents) and nucleic acid combinations. PMID:25557580

Improved Differential Ion Mobility Separations Using Linked Scans of Carrier Gas Composition and Compensation Field

NASA Astrophysics Data System (ADS)

Santiago, Brandon G.; Harris, Rachel A.; Isenberg, Samantha L.; Ridgeway, Mark E.; Pilo, Alice L.; Kaplan, Desmond A.; Glish, Gary L.

2015-07-01

Differential ion mobility spectrometry (DIMS) separates ions based on differences in their mobilities in low and high electric fields. When coupled to mass spectrometric analyses, DIMS has the ability to improve signal-to-background by eliminating isobaric and isomeric compounds for analytes in complex mixtures. DIMS separation power, often measured by resolution and peak capacity, can be improved through increasing the fraction of helium in the nitrogen carrier gas. However, because the mobility of ions is higher in helium, a greater number of ions collide with the DIMS electrodes or housing, yielding losses in signal intensity. To take advantage of the benefits of helium addition on DIMS separations and reduce ion losses, linked scans were developed. In a linked scan the helium content of the carrier gas is reduced as the compensation field is increased. Linked scans were compared with conventional compensation field scans with constant helium content for the protein ubiquitin and a tryptic digest of bovine serum albumin (BSA). Linked scans yield better separation of ubiquitin charge states and enhanced peak capacities for the analysis of BSA compared with compensation field scans with constant helium carrier gas percentages. Linked scans also offer improved signal intensity retention in comparison to compensation field scans with constant helium percentages in the carrier gas.

Progress in the Field of Constructing Near-Infrared Light-Responsive Drug Delivery Platforms.

PubMed

Zhou, Fang; Wang, Hanjie; Chang, Jin

2016-03-01

Stimuli-responsive materials have taken replace of traditional drug carriers due to their ability to achieve controlled release of their encapsulated contents. A variety of sensitive materials, such as polymers that respond to pH, light, and magnetic fields, are widely used to construct drug carriers, and achieved good results. Specifically, near-infrared light (NIR) responsive materials are of particular interest in drug delivery, as NIR can penetrate body tissue and is minimally absorbed by the body's water and hemoglobin and is less harmful to healthy cells than UV or visible light. Thus, the near-infrared excitation drug delivery systems (NIRDDSs) have some essential advantages just like being efficient to kill tumor cells, accurate to achieve the tumor sites and less damage to human body. Also, in the process of building the carriers, we may achieve a combination of controlled release chemotherapy, photothermal therapy (PTT) or photodynamic therapy (PDT). In addition, besides utilizing as drug delivery platforms, some carriers can achieve multifunctional tumor diagnosis and treatment, such as magnetic resonance imaging, optical imaging, drug carriers and PTT. In this review, based on the mechanism of NIR, we highlight diverse near-infrared light-responsive drug delivery platforms and recent advances in the development of NIRDDSs for cancer therapy primarily.

Nano-biomimetic carriers are implicated in mechanistic evaluation of intracellular gene delivery

NASA Astrophysics Data System (ADS)

Alipour, Mohsen; Hosseinkhani, Saman; Sheikhnejad, Reza; Cheraghi, Roya

2017-01-01

Several tissue specific non-viral carriers have been developed for gene delivery purposes. However, the inability to escape endosomes, undermines the efficacy of these carriers. Researchers inspired by HIV and influenza virus, have randomly used Gp41 and H5WYG fusogenic peptides in several gene delivery systems without any rational preference. Here for the first time, we have genetically engineered two Nano-biomimetic carriers composed of either HWYG (HNH) or Gp41 (GNH) that precisely provide identical conditions for the study and evaluation of these fusogenic peptides. The luciferase assay demonstrated a two-fold higher transfection efficiency of HNH compared to GNH. These nanocarriers also displayed equivalent properties in terms of DNA binding ability and DNA protection against serum nucleases and formed similar nanoparticles in terms of surface charge and size. Interestingly, hemolysis and cellular analysis demonstrated both of nanoparticles internalized into cells in similar rate and escaped from endosome with different efficiency. Furthermore, the structural analysis revealed the mechanisms responsible for the superior endosomal escaping capability of H5WYG. In conclusion, this study describes the rationale for using H5WYG peptide to deliver nucleic acids and suggests that using nano-biomimetic carriers to screen different endosomal release peptides, improves gene delivery significantly.

Recent Advances in Lipid-Based Vesicles and Particulate Carriers for Topical and Transdermal Application.

PubMed

Jain, Shashank; Patel, Niketkumar; Shah, Mansi K; Khatri, Pinak; Vora, Namrata

2017-02-01

In the recent decade, skin delivery (topical and transdermal) has gained an unprecedented popularity, especially due to increased incidences of chronic skin diseases, demand for targeted and patient compliant delivery, and interest in life cycle management strategies among pharmaceutical companies. Literature review of recent publications indicates that among various skin delivery systems, lipid-based delivery systems (vesicular carriers and lipid particulate systems) have been the most successful. Vesicular carriers consist of liposomes, ultradeformable liposomes, and ethosomes, while lipid particulate systems consist of lipospheres, solid lipid nanoparticles, and nanostructured lipid carriers. These systems can increase the skin drug transport by improving drug solubilization in the formulation, drug partitioning into the skin, and fluidizing skin lipids. Considering that lipid-based delivery systems are regarded as safe and efficient, they are proving to be an attractive delivery strategy for the pharmaceutical as well as cosmeceutical drug substances. However, development of these delivery systems requires comprehensive understanding of physicochemical characteristics of drug and delivery carriers, formulation and process variables, mechanism of skin delivery, recent technological advancements, specific limitations, and regulatory considerations. Therefore, this review article encompasses recent research advances addressing the aforementioned issues. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Exploring time-resolved photoluminescence for nanowires using a three-dimensional computational transient model.

PubMed

Ren, Dingkun; Scofield, Adam C; Farrell, Alan C; Rong, Zixuan; Haddad, Michael A; Laghumavarapu, Ramesh B; Liang, Baolai; Huffaker, Diana L

2018-04-26

Time-resolved photoluminescence (TRPL) has been implemented experimentally to measure the carrier lifetime of semiconductors for decades. For the characterization of nanowires, the rich information embedded in TRPL curves has not been fully interpreted and meaningfully mapped to the respective material properties. This is because their three-dimensional (3-D) geometries result in more complicated mechanisms of carrier recombination than those in thin films and analytical solutions cannot be found for those nanostructures. In this work, we extend the intrinsic power of TRPL by developing a full 3-D transient model, which accounts for different material properties and drift-diffusion, to simulate TRPL curves for nanowires. To show the capability of the model, we perform TRPL measurements on a set of GaAs nanowire arrays grown on silicon substrates and then fit the measured data by tuning various material properties, including carrier mobility, Shockley-Read-Hall recombination lifetime, and surface recombination velocity at the GaAs-Si heterointerface. From the resultant TRPL simulations, we numerically identify the lifetime characteristics of those material properties. In addition, we computationally map the spatial and temporal electron distributions in nanowire segments and reveal the underlying carrier dynamics. We believe this study provides a theoretical foundation for interpretation of TRPL measurements to unveil the complex carrier recombination mechanisms in 3-D nanostructured materials.

A Simplified Baseband Prefilter Model with Adaptive Kalman Filter for Ultra-Tight COMPASS/INS Integration

PubMed Central

Luo, Yong; Wu, Wenqi; Babu, Ravindra; Tang, Kanghua; Luo, Bing

2012-01-01

COMPASS is an indigenously developed Chinese global navigation satellite system and will share many features in common with GPS (Global Positioning System). Since the ultra-tight GPS/INS (Inertial Navigation System) integration shows its advantage over independent GPS receivers in many scenarios, the federated ultra-tight COMPASS/INS integration has been investigated in this paper, particularly, by proposing a simplified prefilter model. Compared with a traditional prefilter model, the state space of this simplified system contains only carrier phase, carrier frequency and carrier frequency rate tracking errors. A two-quadrant arctangent discriminator output is used as a measurement. Since the code tracking error related parameters were excluded from the state space of traditional prefilter models, the code/carrier divergence would destroy the carrier tracking process, and therefore an adaptive Kalman filter algorithm tuning process noise covariance matrix based on state correction sequence was incorporated to compensate for the divergence. The federated ultra-tight COMPASS/INS integration was implemented with a hardware COMPASS intermediate frequency (IF), and INS's accelerometers and gyroscopes signal sampling system. Field and simulation test results showed almost similar tracking and navigation performances for both the traditional prefilter model and the proposed system; however, the latter largely decreased the computational load. PMID:23012564

Antimicrobial delivery systems for local infection prophylaxis in orthopedic- and trauma surgery.

PubMed

ter Boo, Gert-Jan A; Grijpma, Dirk W; Moriarty, Thomas F; Richards, Robert G; Eglin, David

2015-06-01

Infectious complications occur in a minor but significant portion of the patients undergoing joint replacement surgery or fracture fixation, particularly those with severe open fractures, those undergoing revision arthroplasty or those at elevated risk because of poor health status. Once established, infections are difficult to eradicate, especially in the case of bacterial biofilm formation on implanted hardware. Local antibiotic carriers offer the prospect of controlled delivery of antibiotics directly in target tissues and implant, without inducing toxicity in non-target organs. Polymeric carriers have been developed to optimize the release and targeting of antibiotics. Passive polymeric carriers release antibiotics by diffusion and/or upon degradation, while active polymeric carriers release their antibiotics upon stimuli provided by bacterial pathogens. Additionally, some polymeric carriers gelate in-situ in response to physiological stimuli to form a depot for antibiotic release. As antibiotic resistance has become a major issue, also other anti-infectives such as silver and antimicrobial peptides have been incorporated in research. Currently, several antibiotic loaded biomaterials for local infection prophylaxis are available for use in the clinic. Here we review their advantages and limitations and provide an overview of new materials emerging that may overcome these limitations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of liquid droplets on turbulence in a round gaseous jet

NASA Technical Reports Server (NTRS)

Mostafa, A. A.; Elghobashi, S. E.

1986-01-01

The main objective of this investigation is to develop a two-equation turbulence model for dilute vaporizing sprays or in general for dispersed two-phase flows including the effects of phase changes. The model that accounts for the interaction between the two phases is based on rigorously derived equations for turbulence kinetic energy (K) and its dissipation rate epsilon of the carrier phase using the momentum equation of that phase. Closure is achieved by modeling the turbulent correlations, up to third order, in the equations of the mean motion, concentration of the vapor in the carrier phase, and the kinetic energy of turbulence and its dissipation rate for the carrier phase. The governing equations are presented in both the exact and the modeled formes. The governing equations are solved numerically using a finite-difference procedure to test the presented model for the flow of a turbulent axisymmetric gaseous jet laden with either evaporating liquid droplets or solid particles. The predictions include the distribution of the mean velocity, volume fractions of the different phases, concentration of the evaporated material in the carrier phase, turbulence intensity and shear stress of the carrier phase, droplet diameter distribution, and the jet spreading rate. The predictions are in good agreement with the experimental data.

Infrared countermeasure flare performance measurements using a gas gun

NASA Astrophysics Data System (ADS)

Krishnamoorthy, Lakshmanan; Stringer, Michael; Taylor, Mark R. G.; Kollias, S.

2004-12-01

A unique and cost effective measurement facility called the Reusable Aerodynamic Flare Ejection Capability (RAFEC) has been developed at the Defence Science and Technology Organisation (DSTO), Australia. The RAFEC system involves the use of a reusable, carrier projectile that is launched from a 10 inch, nitrogen driven gas gun. The IRCM flare is loaded in the carrier projectile and the gas gun launches the carrier projectile with a known velocity of between approximately 350 to 650 knots. At a pre-determined time after firing and in the field of view of the measuring instrumentation, the flare is ejected from the carrier projectile for performance measurements to be undertaken. The temporal, spatial and spectral quantities were accomplished with the instruments fielded around the gas gun line of fire and the trajectory is derived from the spatial measurements. The data will be used for hardware in the loop simulations and modelling. Further improvements such as; (1) multiple (maximum of three) flare ejection, (2) 1"x1"x8" format flares made to the carrier projectile, and (3) design and manufacture of the puston, a new item of firing hardware to obtain lower muzzle velocities have enhanced the RAFEC capability. Thus the RAFEC system provides a more realistic IRCM performance measurement capability as it incorporates the deceleration effects experienced by the flare on deployment.

The Prevalence and Molecular Spectrum of α- and β-Globin Gene Mutations in 14,332 Families of Guangdong Province, China

PubMed Central

Xu, Longchang; Wu, Li; Zhang, Liang; Ma, Yuanzhu; Chen, Tingting; Gao, Shuang; Liang, Juqing; Guo, Hao; Qin, Danqing; Wang, Jicheng; Yuan, Tenglong; Wang, Yixia; Huang, Wei-wei; He, Wen-Fei; Zhang, Yanxia; Liu, Chang; Xia, Sujian; Chen, Qingshan; Zhao, Qingguo; Zhang, Xiaozhuang

2014-01-01

Objective To reveal the familial prevalence and molecular variation of α- and β-globin gene mutations in Guangdong Province. Methods A total of 40,808 blood samples from 14,332 families were obtained and analyzed for both hematological and molecular parameters. Results A high prevalence of α- and β-globin gene mutations was found. Overall, 17.70% of pregnant women, 15.94% of their husbands, 16.03% of neonates, and 16.83% of couples (pregnant women and their husbands) were heterozygous carriers of α- or β-thalassemia. The regions with the highest prevalence were the mountainous and western regions, followed by the Pearl River Delta; the region with the lowest prevalence was Chaoshan. The total familial carrier rate (both spouses were α- or β-thalassemia carriers) was 1.87%, and the individual carrier rates of α- and β-thalassemia were 1.68% and 0.20%, respectively. The total rate of moderate-to-severe fetal thalassemia was 12.78% among couples in which both parents were carriers. Conclusions There was a high prevalence of α- and β-thalassemia in Guangdong Province. This study will contribute to the development of thalassemia prevention and control strategies in Guangdong Province. PMID:24587075

Enhanced styrene recovery from waste polystyrene pyrolysis using response surface methodology coupled with Box-Behnken design.

PubMed

Mo, Yu; Zhao, Lei; Wang, Zhonghui; Chen, Chia-Lung; Tan, Giin-Yu Amy; Wang, Jing-Yuan

2014-04-01

A work applied response surface methodology coupled with Box-Behnken design (RSM-BBD) has been developed to enhance styrene recovery from waste polystyrene (WPS) through pyrolysis. The relationship between styrene yield and three selected operating parameters (i.e., temperature, heating rate, and carrier gas flow rate) was investigated. A second order polynomial equation was successfully built to describe the process and predict styrene yield under the study conditions. The factors identified as statistically significant to styrene production were: temperature, with a quadratic effect; heating rate, with a linear effect; carrier gas flow rate, with a quadratic effect; interaction between temperature and carrier gas flow rate; and interaction between heating rate and carrier gas flow rate. The optimum conditions for the current system were determined to be at a temperature range of 470-505°C, a heating rate of 40°C/min, and a carrier gas flow rate range of 115-140mL/min. Under such conditions, 64.52% WPS was recovered as styrene, which was 12% more than the highest reported yield for reactors of similar size. It is concluded that RSM-BBD is an effective approach for yield optimization of styrene recovery from WPS pyrolysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

Carriers for the Tunable Release of Therapeutics: Etymological Classification and Examples

PubMed Central

Uskoković, Vuk; Ghosh, Shreya

2016-01-01

Introduction Physiological processes at the molecular level take place at precise spatiotemporal scales, which vary from tissue to tissue and from one patient to another, implying the need for the carriers that enable tunable release of therapeutics. Areas Covered Classification of all drug release to intrinsic and extrinsic is proposed, followed by the etymological clarification of the term “tunable” and its distinction from the term “tailorable”. Tunability is defined as analogous to tuning a guitar string or a radio receiver to the right frequency using a single knob. It implies changing a structural parameter along a continuous quantitative scale and correlating it numerically with the release kinetics. Examples of tunable, tailorable and environmentally responsive carriers are given, along with the parameters used to achieve these levels of control. Expert Opinion Interdependence of multiple variables defining the carrier microstructure obstructs the attempts to elucidate parameters that allow for the independent tuning of release kinetics. Learning from the tunability of nanostructured materials and superstructured metamaterials can be a fruitful source of inspiration in the quest for the new generation of tunable release carriers. The greater intersection of traditional materials sciences and pharmacokinetic perspectives could foster the development of more sophisticated mechanisms for tunable release. PMID:27322661

Design, development, and evaluation of truck and bus driver wellness programs

DOT National Transportation Integrated Search

2000-06-01

In May 1997, the Federal Motor Carrier Safety Administration (FMCSA) began a research project to design, develop, and evaluate a model truck and bus driver wellness program. This wellness program was developed to provide a resource for addressing tru...

Acoustic manipulation of active spherical carriers: Generation of negative radiation force

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

Rajabi, Majid, E-mail: majid_rajabi@iust.ac.ir; Mojahed, Alireza

2016-09-15

This paper examines theoretically a novel mechanism of generating negative (pulling) radiation force for acoustic manipulation of spherical carriers equipped with piezoelectric actuators in its inner surface. In this mechanism, the spherical particle is handled by common plane progressive monochromatic acoustic waves instead of zero-/higher- order Bessel beams or standing waves field. The handling strategy is based on applying a spatially uniform harmonic electrical voltage at the piezoelectric actuator with the same frequency of handling acoustic waves, in order to change the radiation force effect from repulsive (away from source) to attractive (toward source). This study may be considered asmore » a start point for development of contact-free precise handling and entrapment technology of active carriers which are essential in many engineering and medicine applications.« less

Recent advances in galactose-engineered nanocarriers for the site-specific delivery of siRNA and anticancer drugs.

PubMed

Jain, Ashay; Jain, Atul; Parajuli, Prahlad; Mishra, Vijay; Ghoshal, Gargi; Singh, Bhupinder; Shivhare, Uma Shankar; Katare, Om Prakash; Kesharwani, Prashant

2018-05-01

Galactosylated nanocarriers have recently emerged as viable and versatile tools to deliver drugs at an optimal rate specifically to their target tissues or cells, thus maximizing their therapeutic benefits while circumventing off-target effects. The abundance of lectin receptors on cell surfaces makes the galactosylated carriers suitable for the targeted delivery of bioactives. Additionally, tethering of galactose (GAL) to various carriers, including micelles, liposomes, and nanoparticles (NPs), might also be appropriate for drug delivery. Here, we review recent advances in the development of galactosylated nanocarriers for active tumor targeting. We also provide a brief overview of the targeting mechanisms and cell receptor theory involved in the ligand-receptor-mediated delivery of drug carriers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of high-efficiency solar cells on silicon web

NASA Technical Reports Server (NTRS)

Meier, D. L.; Greggi, J.; Okeeffe, T. W.; Rai-Choudhury, P.

1986-01-01

Work was performed to improve web base material with a goal of obtaining solar cell efficiencies in excess of 18% (AM1). Efforts in this program are directed toward identifying carrier loss mechanisms in web silicon, eliminating or reducing these mechanisms, designing a high efficiency cell structure with the aid of numerical models, and fabricating high efficiency web solar cells. Fabrication techniques must preserve or enhance carrier lifetime in the bulk of the cell and minimize recombination of carriers at the external surfaces. Three completed cells were viewed by cross-sectional transmission electron microscopy (TEM) in order to investigate further the relation between structural defects and electrical performance of web cells. Consistent with past TEM examinations, the cell with the highest efficiency (15.0%) had no dislocations but did have 11 twin planes.

Charge transfer polarisation wave and carrier pairing in the high T(sub c) copper oxides

NASA Technical Reports Server (NTRS)

Chakraverty, B. K.

1990-01-01

The High T(sub c) oxides are highly polarizable materials and are charge transfer insulators. The charge transfer polarization wave formalism is developed in these oxides. The dispersion relationships due to long range dipole-dipole interaction of a charge transfer dipole lattice are obtained in 3-D and 2-D. These are high frequency bosons and their coupling with carriers is weak and antiadiabatic in nature. As a result, the mass renormalization of the carriers is negligible in complete contrast to conventional electron-phonon interaction, that give polarons and bipolarons. Both bound and superconducting pairing is discussed for a model Hamiltonian valid in the antiadiabatic regime, both in 3-D and 2-D. The stability of the charge transfer dipole lattice has interesting consequences that are discussed.

Pharmacological aspects of release from microcapsules - from polymeric multilayers to lipid membranes.

PubMed

Wuytens, Pieter; Parakhonskiy, Bogdan; Yashchenok, Alexey; Winterhalter, Mathias; Skirtach, Andre

2014-10-01

This review is devoted to pharmacological applications of principles of release from capsules to overcome the membrane barrier. Many of these principles were developed in the context of polymeric multilayer capsule membrane modulation, but they are also pertinent to liposomes, polymersomes, capsosomes, particles, emulsion-based carriers and other carriers. We look at these methods from the physical, chemical or biological driving mechanisms point of view. In addition to applicability for carriers in drug delivery, these release methods are significant for another area directly related to pharmacology - modulation of the permeability of the membranes and thus promoting the action of drugs. Emerging technologies, including ionic current monitoring through a lipid membrane on a nanopore, are also highlighted. Copyright © 2014 Elsevier Ltd. All rights reserved.

Immobilization of l-Asparaginase on Carrier Materials: A Comprehensive Review.

PubMed

Ulu, Ahmet; Ates, Burhan

2017-06-21

There are two major applications of l-asparaginase (L-ASNase): leukemia therapy and the food industry. Especially, its chemotherapeutic effect has attracted interest from the scientific community and individual scientists. Therefore, to protect the intrinsic activity and half-time of L-ASNase, several carriers and immobilization techniques for immobilization of L-ASNase have been described in articles. Unfortunately, a comprehensive review about immobilization of L-ASNase has not been written until now. In this review, we have thoroughly discussed the carriers for L-ASNase by illustrating immobilization findings including both past and present applications. In addition, we have revealed advantages and disadvantages of immobilized enzyme and related it to free form. We believe that this review will not only provide background information, but also guide future developments.

Reversible Conversion of Dominant Polarity in Ambipolar Polymer/Graphene Oxide Hybrids

PubMed Central

Zhou, Ye; Han, Su-Ting; Sonar, Prashant; Ma, Xinlei; Chen, Jihua; Zheng, Zijian; Roy, V. A. L.

2015-01-01

The possibility to selectively modulate the charge carrier transport in semiconducting materials is extremely challenging for the development of high performance and low-power consuming logic circuits. Systematical control over the polarity (electrons and holes) in transistor based on solution processed layer by layer polymer/graphene oxide hybrid system has been demonstrated. The conversion degree of the polarity is well controlled and reversible by trapping the opposite carriers. Basically, an electron device is switched to be a hole only device or vice versa. Finally, a hybrid layer ambipolar inverter is demonstrated in which almost no leakage of opposite carrier is found. This hybrid material has wide range of applications in planar p-n junctions and logic circuits for high-throughput manufacturing of printed electronic circuits. PMID:25801827

Optimization of territory control of the mail carrier by using Hungarian methods

NASA Astrophysics Data System (ADS)

Supian, S.; Wahyuni, S.; Nahar, J.; Subiyanto

2018-03-01

In this paper, the territory control of the mail carrier from the central post office Bandung in delivering the package to the destination location was optimized by using Hungarian method. Sensitivity analysis against data changes that may occur was also conducted. The sampled data in this study are the territory control of 10 mail carriers who will be assigned to deliver mail package to 10 post office delivery centers in Bandung. The result of this research is the combination of territory control optimal from 10 mail carriers as follows: mail carrier 1 to Cikutra, mail carrier 2 to Ujung Berung, mail carrier 3 to Dayeuh Kolot, mail carrier 4 to Padalarang, mail carrier 5 to Situ Saeur, mail carrier 6 to Cipedes, mail carrier 7 to Cimahi, mail carrier 8 to Soreang, mail carrier 9 to Asia-Afrika, mail carrier 10 to Cikeruh. Based on this result, manager of the central post office Bandung can make optimal decisions to assign tasks to their mail carriers.

Spectral estimation of received phase in the presence of amplitude scintillation

NASA Technical Reports Server (NTRS)

Vilnrotter, V. A.; Brown, D. H.; Hurd, W. J.

1988-01-01

A technique is demonstrated for obtaining the spectral parameters of the received carrier phase in the presence of carrier amplitude scintillation, by means of a digital phased locked loop. Since the random amplitude fluctuations generate time-varying loop characteristics, straightforward processing of the phase detector output does not provide accurate results. The method developed here performs a time-varying inverse filtering operation on the corrupted observables, thus recovering the original phase process and enabling accurate estimation of its underlying parameters.

The Carrier Arms Race in East and South Asia: Responses to a Changing Strategic Environment

DTIC Science & Technology

2014-09-01

analysis of Japan’s strategic trajectory and the development of new classes of helicopter destroyers. Koda describes the U.S.-Japan security alliance... Koda , “A New Carrier Race? Strategy, Force Planning, and JS Hyuga.” Naval War College Review 64, no. 3 (2011): 32–51. 11 Korean Institute for...According to retired Vice Admiral Yoji Koda , “Hyuga realizes a long-standing dream and goal of the JMSDF, which has wanted to be a truly capable

Current Progress in Gene Delivery Technology Based on Chemical Methods and Nano-carriers

PubMed Central

Jin, Lian; Zeng, Xin; Liu, Ming; Deng, Yan; He, Nongyue

2014-01-01

Gene transfer methods are promising in the field of gene therapy. Current methods for gene transfer include three major groups: viral, physical and chemical methods. This review mainly summarizes development of several types of chemical methods for gene transfer in vitro and in vivo by means of nano-carriers like; calcium phosphates, lipids, and cationic polymers including chitosan, polyethylenimine, polyamidoamine dendrimers, and poly(lactide-co-glycolide). This review also briefly introduces applications of these chemical methods for gene delivery. PMID:24505233

Measurement of irregularities in angular velocities of rotating assemblies in memory devices on magnetic carriers

NASA Technical Reports Server (NTRS)

Virakas, G. I.; Matsyulevichyus, R. A.; Minkevichyus, K. P.; Potsyus, Z. Y.; Shirvinskas, B. D.

1973-01-01

Problems in measurement of irregularities in angular velocity of rotating assemblies in memory devices with rigid and flexible magnetic data carriers are discussed. A device and method for determination of change in angular velocities in various frequency and rotation rate ranges are examined. A schematic diagram of a photoelectric sensor for recording the signal pulses is provided. Mathematical models are developed to show the amount of error which can result from misalignment of the test equipment.

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

Petach, Trevor A.; Reich, Konstantin V.; Zhang, Xiao

Ionic liquid gating has a number of advantages over solid-state gating, especially for flexible or transparent devices and for applications requiring high carrier densities. But, the large number of charged ions near the channel inevitably results in Coulomb scattering, which limits the carrier mobility in otherwise clean systems. We develop a model for this Coulomb scattering. We then validate our model experimentally using ionic liquid gating of graphene across varying thicknesses of hexagonal boron nitride, demonstrating that disorder in the bulk ionic liquid often dominates the scattering.

Electrochemical impedance analysis of perovskite–electrolyte interfaces

DOE PAGES

Li, Zhen; Mercado, Candy C.; Yang, Mengjin; ...

2017-01-31

Here, the flat band potentials and carrier densities of spin coated and sprayed MAPbI 3, FA 0.85Cs 0.15PbI 3, and MAPbBr 3 perovskite films were determined using the Mott-Schottky relation. The films developed a space charge layer and exhibited p-type conduction with carrier concentration ~ 10 16 cm -3 for spin coated films. Electrochemical impedance spectra showed typical space charge impedance at frequencies > 1 kHz with increasing capacitance < 1 kHz owing to an ion diffusion component.

Advanced methods for preparation and characterization of infrared detector materials

NASA Technical Reports Server (NTRS)

Broerman, J. G.; Morris, B. J.; Meschter, P. J.

1983-01-01

Crystals were prepared by the Bridgman-Stockbarger method with a wide range of crystal growth rates and temperature gradients adequate to prevent constitutional supercooling under diffusion-limited, steady-state, growth conditions. The longitudinal compositional gradients for different growth conditions and alloy compositions were calculated and compared with experimental data to develop a quantitative model of solute redistribution during the crystal growth of the alloys. Measurements were performed to ascertain the effect of growth conditions on radial compositional gradients. The pseudobinary HgTe-CdTe constitutional phase diagram was determined by precision differential-thermal-analysis measurements and used to calculate the segregation coefficient of Cd as a function of x and interface temperature. Experiments were conducted to determine the ternary phase equilibria in selected regions of the Hg-Cd-Te constitutional phase diagram. Electron and hole mobilities as functions of temperature were analyzed to establish charge-carrier scattering probabilities. Computer algorithms specific to Hg(1-x)CdxTe were developed for calculations of the charge-carrier concentration, charge-carrier mobilities, Hall coefficient, and Dermi Fermi energy as functions of x, temperature, ionized donor and acceptor concentrations, and neutral defect concentrations.

Structural DNA nanotechnology for intelligent drug delivery.

PubMed

Chao, Jie; Liu, Huajie; Su, Shao; Wang, Lianhui; Huang, Wei; Fan, Chunhai

2014-11-01

Drug delivery carriers have been popularly employed to improve solubility, stability, and efficacy of chemical and biomolecular drugs. Despite the rapid progress in this field, it remains a great challenge to develop an ideal carrier with minimal cytotoxicity, high biocompatibility and intelligence for targeted controlled release. The emergence of DNA nanotechnology offers unprecedented opportunities in this regard. Due to the unparalleled self-recognition properties of DNA molecules, it is possible to create numerous artificial DNA nanostructures with well-defined structures and DNA nanodevices with precisely controlled motions. More importantly, recent studies have proven that DNA nanostructures possess greater permeability to the membrane barrier of cells, which pave the way to developing new drug delivery carriers with nucleic acids, are summarized. In this Concept, recent advances on the design and fabrication of both static and dynamic DNA nanostructures, and the use of these nanostructures for the delivery of various types of drugs, are highlighted. It is also demonstrated that dynamic DNA nanostructures provide the required intelligence to realize logically controlled drug release. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Stoddard, Ryan J.; Eickemeyer, Felix T.; Katahara, John K.

High-bandgap mixed-halide hybrid perovskites have higher open-circuit voltage deficits and lower carrier diffusion lengths than their lower-bandgap counterparts. We have developed a ligand-assisted crystallization (LAC) technique that introduces additives in situ during the solvent wash and developed a new method to dynamically measure the absolute intensity steady-state photoluminescence and the mean carrier diffusion length simultaneously. The measurements reveal four distinct regimes of material changes and show that photoluminescence brightening often coincides with losses in carrier transport, such as in degradation or phase segregation. Further, the measurements enabled optimization of LAC on the 1.75 eV bandgap FA 0.83Cs 0.17Pb(I 0.66Br 0.34)more » 3, resulting in an enhancement of the photoluminescence quantum yield (PLQY) of over an order of magnitude, an increase of 80 meV in the quasi-Fermi level splitting (to 1.29 eV), an increase in diffusion length by a factor of 3.5 (to over 1 μm), and enhanced open-circuit voltage and short-circuit current from photovoltaics fabricated from the LAC-treated films.« less

Solution-Processed Metal Oxides as Efficient Carrier Transport Layers for Organic Photovoltaics.

PubMed

Choy, Wallace C H; Zhang, Di

2016-01-27

Carrier (electron and hole) transport layers (CTLs) are essential components for boosting the performance of various organic optoelectronic devices such as organic solar cells and organic light-emitting diodes. Considering the drawbacks of conventional CTLs (easily oxidized/unstable, demanding/costly fabrication, etc.), transition metal oxides with good carrier transport/extraction and superior stability have drawn extensive research interest as CTLs for next-generation devices. In recent years, many research efforts have been made toward the development of solution-based metal oxide CTLs with the focus on low- or even room-temperature processes, which can potentially be compatible with the deposition processes of organic materials and can significantly contribute to the low-cost and scale-up of organic devices. Here, the recent progress of different types of solution-processed metal oxide CTLs are systematically reviewed in the context of organic photovoltaics, from synthesis approaches to device performance. Different approaches for further enhancing the performance of solution-based metal oxide CTLs are also discussed, which may push the future development of this exciting field. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of carrier-based formulation of root endophyte Piriformospora indica and its evaluation on Phaseolus vulgaris L.

PubMed

Tripathi, Swati; Das, Aparajita; Chandra, Anil; Varma, Ajit

2015-02-01

Endophytic fungi are plant beneficial rhizospheric microorganisms often applied as bioinoculants for enhanced and disease-free crop production. The objectives of the present work were to develop a carrier-based formulation of root endophyte Piriformospora indica as a bioinoculant. Powder formulation of four different carrier materials viz., talcum powder, clay, sawdust and bioboost (organic supplement) were evaluated and a talc-based formulation was optimized for a longer shelf life with respect to microbial concentration, storage temperature and biological activity. Finally the effect of optimized talc formulation on plant productivity was determined. The application dosages were optimized by studies on plant growth parameters of Phaseolus vulgaris L. plants under green house conditions. Five percent formulation (w/w) of talcum powder was observed to be the most stable at 30 °C with 10(8) CFU g(-1) and effective for a storage period of 6 months. The application of this optimized formulation resulted in increase of growth parameters of P. vulgaris L. and better adaptation of plants under green house conditions.

Exciton shelves for charge and energy transport in third-generation quantum-dot devices

NASA Astrophysics Data System (ADS)

Goodman, Samuel; Singh, Vivek; Noh, Hyunwoo; Casamada, Josep; Chatterjee, Anushree; Cha, Jennifer; Nagpal, Prashant

2014-03-01

Quantum dots are semiconductor nanocrystallites with size-dependent quantum-confined energy levels. While they have been intensively investigated to utilize hot-carriers for photovoltaic applications, to bridge the mismatch between incident solar photons and finite bandgap of semiconductor photocells, efficient charge or exciton transport in quantum-dot films has proven challenging. Here we show development of new coupled conjugated molecular wires with ``exciton shelves'', or different energy levels, matched with the multiple energy levels of quantum dots. Using single nanoparticle and ensemble device measurements we show successful extraction and transport of both bandedge and high-energy charge carriers, and energy transport of excitons. We demonstrate using measurements of electronic density of states, that careful matching of energy states of quantum-dot with molecular wires is important, and any mismatch can generate midgap states leading to charge recombination and reduced efficiency. Therefore, these exciton-shelves and quantum dots can lead to development of next-generation photovoltaic and photodetection devices using simultaneous transport of bandedge and hot-carriers or energy transport of excitons in these nanostructured solution-processed films.

14 CFR 221.204 - Adoption of provisions of one carrier by another carrier.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Adoption of provisions of one carrier by another carrier. When one carrier adopts the tariffs of another carrier, the effective and prospective fares of the adopted carrier shall be changed to reflect the name of the adopting carrier and the effective date of the adoption. Further, each adopted fare shall bear...

Development and Validation of an Instrument to Measure the Impact of Genetic Testing on Self-Concept in Lynch Syndrome (LS)

PubMed Central

Esplen, Mary Jane; Stuckless, Noreen; Wong, Jiahui; Gallinger, Steve; Aronson, Melyssa; Rothenmund, Heidi; Semotiuk, Kara; Stokes, Jackie; Way, Chris; Green, Jane; Butler, Kate; Petersen, Helle Vendel

2011-01-01

Background A positive genetic test result may impact on a person’s self-concept and affect quality of life. Purpose The purpose of the study was to develop a self concept scale to measure such impact for individuals carrying mutations for a heritable colorectal cancer- Lynch Syndrome (LS). Methods Two distinct phases were involved: Phase 1 generated specific colorectal self-concept candidate scale items from interviews with eight LS carriers and five genetic counselors which were added to a previously developed self-concept scale for BRCA1/2 mutation carriers. Phase II had 115 LS carriers complete the candidate scale and a battery of validating measures. Results A 20 item scale was developed with two dimensions identified through factor analysis: stigma/vulnerability and bowel symptom-related anxiety. The scale demonstrated excellent reliability (Cronbach’s α = .93), good convergent validity by a high correlation with impact of event scale (r(102) = .55, p< .001) and Rosenberg Self-Esteem Scale (r(108) = −.59, p< .001), and a low correlation with the Fear questionnaire (r(108)=.37 p< .001). The scale’s performance was stable across participant characteristics. Conclusions This new scale for measuring self-concept has potential to be used as a clinical tool and as a measure for future studies. PMID:21883167

Development and validation of an instrument to measure the impact of genetic testing on self-concept in Lynch syndrome.

PubMed

Esplen, M J; Stuckless, N; Gallinger, S; Aronson, M; Rothenmund, H; Semotiuk, K; Stokes, J; Way, C; Green, J; Butler, K; Petersen, H V; Wong, J

2011-11-01

A positive genetic test result may impact on a person's self-concept and affect quality of life. The purpose of the study was to develop a self-concept scale to measure such impact for individuals carrying mutations for a heritable colorectal cancer Lynch syndrome (LS). Two distinct phases were involved: Phase 1 generated specific colorectal self-concept candidate scale items from interviews with eight LS carriers and five genetic counselors, which were added to a previously developed self-concept scale for BRCA1/2 mutation carriers, Phase II had 115 LS carriers complete the candidate scale and a battery of validating measures. A 20-item scale was developed with two dimensions identified through factor analysis: stigma/vulnerability and bowel symptom-related anxiety. The scale showed excellent reliability (Cronbach's α = 0.93), good convergent validity by a high correlation with impact of event scale (r(102) = 0.55, p < 0.001) and Rosenberg self-esteem scale (r(108) = -0.59, p < 0.001), and a low correlation with the Fear questionnaire (r(108) = 0.37, p < 0.001). The scale's performance was stable across participant characteristics. This new scale for measuring self-concept has potential to be used as a clinical tool and as a measure for future studies. © 2011 John Wiley & Sons A/S.

Hereditary diffuse gastric cancer: implications of genetic testing for screening and prophylactic surgery.

PubMed

Cisco, Robin M; Ford, James M; Norton, Jeffrey A

2008-10-01

Approximately 10% of patients with gastric cancer show familial clustering, and 3% show autosomal dominance and high penetrance. Hereditary diffuse gastric cancer (HDGC) is an autosomal-dominant, inherited cancer syndrome in which affected individuals develop diffuse-type gastric cancer at a young age. Inactivating mutations in the E-cadherin gene CDH1 have been identified in 30% to 50% of patients. CDH1 mutation carriers have an approximately 70% lifetime risk of developing DGC, and affected women carry an additional 20% to 40% risk of developing lobular breast cancer. Because endoscopic surveillance is ineffective in identifying early HDGC, gene-directed prophylactic total gastrectomy currently is offered for CDH1 mutation carriers. In series of asymptomatic individuals undergoing total gastrectomy for CDH1 mutations, the removed stomachs usually contain small foci of early DGC, making surgery not prophylactic but curative. The authors of this review recommend consideration of total gastrectomy in CDH1 mutation carriers at an age 5 years younger than the youngest family member who developed gastric cancer. Individuals who choose not to undergo prophylactic gastrectomy should be followed with biannual chromoendoscopy, and women with CDH1 mutations also should undergo regular surveillance with magnetic resonance imaging studies of the breast. Because of the emergence of gene-directed gastrectomy for HDGC, today, a previously lethal disease is detected by molecular techniques, allowing curative surgery at an early stage.

SDHB-related pheochromocytoma and paraganglioma penetrance and genotype-phenotype correlations.

PubMed

Jochmanova, Ivana; Wolf, Katherine I; King, Kathryn S; Nambuba, Joan; Wesley, Robert; Martucci, Victoria; Raygada, Margarita; Adams, Karen T; Prodanov, Tamara; Fojo, Antonio Tito; Lazurova, Ivica; Pacak, Karel

2017-08-01

Succinate dehydrogenase subunit B (SDHB) gene mutations are associated with an aggressive clinical disease course of pheochromocytoma/paraganglioma (PHEO/PGL). Limited information is available concerning PHEO/PGL penetrance among SDHB mutation carriers with regards to primary tumor location, specific mutation type, and gender. We assessed PHEO/PGL penetrance in SDHB mutation carriers and described the clinical presentation and disease course. Asymptomatic relatives (N = 611) of 103 index patients were tested for SDHB mutations. Mutation carriers (N = 328) were offered PHEO/PGL screening, of which 241 participated and were included in penetrance analysis. For additional disease outcome analysis, the 103 index patients and 40 screened individuals who developed PHEO/PGL were included. Clinical data were collected between October 2004 and June 2016. Forty (16.60%) of the 241 screened individuals developed PHEO/PGL during the study. The penetrance estimate in this population was 49.80% (95% CI 29-74.9) at 85 years. A significantly higher age-related penetrance of disease was observed in males compared to females, with 50% penetrance achieved at age 74 vs. not reached. Age-related penetrance analysis demonstrated 4 mutations (Ile127Ser, IVS1+1G>T, Exon 1 deletion, Arg90X) presenting with a slower rate of disease development (50% penetrance ages, respectively: not achieved, 70, 63, 61 years) compared to Arg46X and Val140Phe mutations (50% penetrance at 38 years). Here, we found a higher estimated penetrance compared to several other studies, and a striking difference in age-related penetrance between male and female SDHB mutation carriers with no association between mutation and gender or tumor location.

T1 Measurements Identify Extracellular Volume Expansion in Hypertrophic Cardiomyopathy Sarcomere Mutation Carriers With and Without Left Ventricular Hypertrophy

PubMed Central

Ho, Carolyn Y.; Abbasi, Siddique A.; Neilan, Tomas G.; Shah, Ravi V.; Chen, Yucheng; Heydari, Bobak; Cirino, Allison L.; Lakdawala, Neal K.; Orav, E. John; González, Arantxa; López, Begoña; Díez, Javier; Jerosch-Herold, Michael; Kwong, Raymond Y.

2013-01-01

Background Myocardial fibrosis is a hallmark of hypertrophic cardiomyopathy (HCM) and a potential substrate for arrhythmias and heart failure. Sarcomere mutations appear to induce profibrotic changes before left ventricular hypertrophy (LVH) develops. To further evaluate these processes, we used cardiac magnetic resonance (CMR) with T1 measurements on a genotyped HCM population to quantify myocardial extracellular volume (ECV). Methods and Results Sarcomere mutation carriers with LVH (G+/LVH+, n = 37) and without LVH (G+/LVH−, n = 29); HCM patients without mutations (sarcomere-negative HCM, n = 11); and healthy controls (n = 11) underwent contrast CMR, measuring T1 times pre- and post-gadolinium infusion. Concurrent echocardiography and serum biomarkers of collagen synthesis, hemodynamic stress, and myocardial injury were also available in a subset. Compared to controls, ECV was increased in patients with overt HCM, as well as G+/LVH− mutation carriers (ECV= 0.36±0.01, 0.33±0.01, 0.27±0.01 in G+/LVH+, G+/LVH−, controls, respectively, P≤0.001 for all comparisons). ECV correlated with NT-proBNP levels (r = 0.58, P<0.001) and global E’ velocity (r = −0.48, P<0.001). Late gadolinium enhancement (LGE) was present in >60% of overt HCM patients but absent from G+/LVH− subjects. Both ECV and LGE were more extensive in sarcomeric HCM than sarcomere-negative HCM. Conclusions Myocardial ECV is increased in HCM sarcomere mutation carriers even in the absence of LVH. These data provide additional support that fibrotic remodeling is triggered early in disease pathogenesis. Quantifying ECV may help characterize the development myocardial fibrosis in HCM and ultimately assist in developing novel disease-modifying therapy, targeting interstitial fibrosis. PMID:23549607

Spinal cord infarction in carriers of methylenetetrahydrofolate reductase-polymorphism-like unique risk factor: report of two cases.

PubMed

Tejero-Fernández, V; Fernández-Rodríguez, I; Membrilla-Mesa, M D; Arroyo-Morales, M

2014-11-01

A case report. To present two cases of spinal cord infarction (SCI) in carriers of the C677T methylenetetrahydrofolate reductase (MTHFR) polymorphism. Physical Medicine and Rehabilitation Department, Section for Rehabilitation and Traumatology, Hospital Virgen de las Nieves, Granada, Spain. Two cases are presented, one with SCI at the C7 level American Spinal Injury Association (ASIA) A and one at the C5 level (ASIA A). One patient presented an acute onset of tetraplegia and the other a centromedular syndrome. In both cases the patients were carriers of the MTHFR polymorphism, which is a unique risk factor. Increased blood levels of homocysteine related to mutation of the MTHFR gene increase the risk of a thrombotic episode, triggering the development of SCI. These two cases increase the limited number reported in the recent literature regarding MTHFR polymorphism carriers suffering from thrombotic SCI. MTHFR mutation can be considered a risk factor for thrombotic SCI, but it is not the sole risk factor. We propose that a consensus regarding the inclusion of anticoagulation treatment after confirmation of the diagnosis in these patients is needed.

Irreversibility and carriers control in two-dimensional electron gas at LaTiO3/SrTiO3 interface

NASA Astrophysics Data System (ADS)

Bergeal, N.; Biscaras, J.; Hurand, S.; Feuillet-Palma, C.; Lesueur, J.; Rastogi, A.; Budhani, R. C.; Reyren, N.; Lesne, E.; Leboeuf, D.; Proust, C.

2013-03-01

It has been shown recently that a two-dimensional electron gas 2DEG could form at the interface of two insulators such as LaAlO3 and SrTiO3, or LaTiO3 (a Mott insulator) and SrTiO3. We present low temperature transport measurements on LaTiO3/SrTiO3 and LaAlO3/SrTiO3 hetero-structures, whose properties can be modulated by field effect using a metallic gate on the back of the substrate. Here we show that when the carrier density is electrostatically increased beyond a critical value, the added electrons escape into the SrTiO3 leading to an irreversible doping regime where all the electronic properties of the 2DEG saturate (carrier density, resistivity, superconducting transition...). The dynamic of leakage was studied using time resolved measurement. Based on a complete self-consistent description of the confinement well, a thermal model for the carriers escape has been developed, which quantitatively accounts for the data.

New Carrier Made from Glass Nanofibres for the Colorimetric Biosensor of Cholinesterase Inhibitors.

PubMed

Matějovský, Lukáš; Pitschmann, Vladimír

2018-05-30

Cholinesterase inhibitors are widely used as pesticides in agriculture, but also form a group of organophosphates known as nerve chemical warfare agents. This calls for close attention regarding their detection, including the use of various biosensors. One such biosensor made in the Czech Republic is the Detehit, which is based on a cholinesterase reaction that is assessed using a colour indicator-the Ellman's reagent-which is anchored on cellulose filter paper together with the substrate. With the use of this biosensor, detection is simple, quick, and sensitive. However, its disadvantage is that a less pronounced yellow discoloration occurs, especially under difficult light conditions. As a possible solution, a new indicator/substrate carrier has been designed. It is made of glass nanofibres, so the physical characteristics of the carrier positively influence reaction conditions, and as a result improve the colour response of the biosensor. The authors present and discuss some of the results of the study of this carrier under various experimental conditions. These findings have been used for the development of a modified Detehit biosensor.

Effects of organic solvents on drug incorporation into polymeric carriers and morphological analyses of drug-incorporated polymeric micelles.

PubMed

Harada, Yoshiko; Yamamoto, Tatsuhiro; Sakai, Masaru; Saiki, Toshiharu; Kawano, Kumi; Maitani, Yoshie; Yokoyama, Masayuki

2011-02-14

We incorporated an anticancer agent, camptothecin (CPT), into polymeric micelle carriers by using two different solvents (TFE and chloroform) in the solvent-evaporation drug incorporation process. We observed significant differences in the drug-incorporation behaviors, in the morphologies of the incorporated drug and the polymeric micelles, and in the pharmacokinetic behaviors between the two solvents' cases. In particular, the CPT-incorporated polymeric micelles prepared with TFE as the incorporation solvent exhibited more stable circulation in blood than those prepared with chloroform. This contrast indicates a novel technological perspective regarding the drug incorporation into polymeric micelle carriers. Morphological analyses of the inner core have revealed the presence of the directed alignment of the CPT molecules and CPT crystals in the micelle inner core. This is the first report of the morphologies of the drug incorporated into the polymeric micelle inner cores. We believe these analyses are very important for further pharmaceutical developments of polymeric micelle drug-carrier systems. Copyright © 2010 Elsevier B.V. All rights reserved.

Time-resolved correlative optical microscopy of charge-carrier transport, recombination, and space-charge fields in CdTe heterostructures

DOE PAGES

Kuciauskas, Darius; Myers, Thomas H.; Barnes, Teresa M.; ...

2017-02-20

From time- and spatially resolved optical measurements, we show that extended defects can have a large effect on the charge-carrier recombination in II-VI semiconductors. In CdTe double heterostructures grown by molecular beam epitaxy on the InSb (100)-orientation substrates, we characterized the extended defects and found that near stacking faults the space-charge field extends by 2-5 μm. Charge carriers drift (with the space-charge field strength of 730-1,360 V cm -1) and diffuse (with the mobility of 260 ± 30 cm 2 V -1 s -1) toward the extended defects, where the minority-carrier lifetime is reduced from 560 ns to 0.25 ns.more » Furthermore, the extended defects are nonradiative recombination sinks that affect areas significantly larger than the typical crystalline grains in II-VI solar cells. From the correlative time-resolved photoluminescence and second-harmonic generation microscopy data, we developed a band-diagram model that can be used to analyze the impact of extended defects on solar cells and other electronic devices.« less

Study on additional carrier sensing for IEEE 802.15.4 wireless sensor networks.

PubMed

Lee, Bih-Hwang; Lai, Ruei-Lung; Wu, Huai-Kuei; Wong, Chi-Ming

2010-01-01

Wireless sensor networks based on the IEEE 802.15.4 standard are able to achieve low-power transmissions in the guise of low-rate and short-distance wireless personal area networks (WPANs). The slotted carrier sense multiple access with collision avoidance (CSMA/CA) is used for contention mechanism. Sensor nodes perform a backoff process as soon as the clear channel assessment (CCA) detects a busy channel. In doing so they may neglect the implicit information of the failed CCA detection and further cause the redundant sensing. The blind backoff process in the slotted CSMA/CA will cause lower channel utilization. This paper proposes an additional carrier sensing (ACS) algorithm based on IEEE 802.15.4 to enhance the carrier sensing mechanism for the original slotted CSMA/CA. An analytical Markov chain model is developed to evaluate the performance of the ACS algorithm. Both analytical and simulation results show that the proposed algorithm performs better than IEEE 802.15.4, which in turn significantly improves throughput, average medium access control (MAC) delay and power consumption of CCA detection.

Development of bio-fuel from palm frond via fast pyrolysis

NASA Astrophysics Data System (ADS)

Solikhah, M. D.; Raksodewanto, A. A.; Kismanto, A.; Karuana, F.; Heryana, Y.; Riza; Pratiwi, F. T.

2017-05-01

In order to fulfill the fuel demand in the future, Indonesia has to find a sustainable alternative for its energy. Energy source in the form of biomass is a promising alternative since its availability is abundance in this tropical country. Biomass can be converted into liquid fuel via fast pyrolysis by contacting the solid biomass into hot medium in the absence of oxygen. Hot sand is the common heat carrier for fast pyrolysis purposes but it is very abrasive and required high pyrolysis temperature (450-600 °C). This paper will discuss on the equipment design and experiment of fast pyrolysis of palm frond using high boiling point thermal oil as heat carrier. Experiments show that by using thermal oil as heat carrier, bio-oil can be produced at lower pyrolysis temperature of 350 °C, compared to the one using hot sand as heating carrier. The yield of bio-oil production is 36.4 % of biomass feeding. The water content of bio-oil is 52.77 % mass while heating value is 10.25 MJ/kg.

Startup pattern and performance enhancement of pilot-scale biofilm process for raw water pretreatment.

PubMed

Yang, Guang-Feng; Feng, Li-Juan; Yang, Qi; Zhu, Liang; Xu, Jian; Xu, Xiang-Yang

2014-11-01

The quality of raw water is getting worse in developing countries because of the inadequate treatment of municipal sewage, industrial wastewater and agricultural runoff. Aiming at the biofilm enrichment and pollutant removal, two pilot-scale biofilm reactors were built with different biological carriers. Results showed that compared with the blank carrier, the biofilm was easily enriched on the biofilm precoated carrier and less nitrite accumulation occurred. The removal efficiencies of NH4(+)-N, DOC and UV254 increased under the aeration condition, and a optimum DO level for the adequate nitrification was 1.0-2.6mgL(-1) with the suitable temperature range of 21-22°C. Study on the trihalomethane prediction model indicated that the presentence of algae increased the risk of disinfection by-products production, which could be effectively controlled via manual algae removing and light shading. In this study, the performance of biofilm pretreatment process could be enhanced under the optimized condition of DO level and biofilm carrier. Copyright © 2014 Elsevier Ltd. All rights reserved.

A novel analytical model for scattering limited electron transport in nano-dimensional InAlAs/InGaAs heterostructure for cryogenic applications

NASA Astrophysics Data System (ADS)

Sharma, Neetika; Verma, Neha; Jogi, Jyotika

2017-11-01

This paper models the scattering limited electron transport in a nano-dimensional In0.52Al0.48As/In0.53Ga0.47As/InP heterostructure. An analytical model for temperature dependent sheet carrier concentration and carrier mobility in a two dimensional electron gas, confined in a triangular potential well has been developed. The model accounts for all the major scattering process including ionized impurity scattering and lattice scattering. Quantum mechanical variational technique is employed for studying the intrasubband scattering mechanism in the two dimensional electron gas. Results of various scattering limited structural parameters such as energy band-gap and functional parameters such as sheet carrier concentration, scattering rate and mobility are presented. The model corroborates the dominance of ionized impurity scattering mechanism at low temperatures and that of lattice scattering at high temperatures, both in turn limiting the carrier mobility. Net mobility obtained taking various scattering mechanisms into account has been found in agreement with earlier reported results, thus validating the model.

Behavior of macroporous vinyl silica and silica monolithic columns in high pressure gas chromatography.

PubMed

Maniquet, Adrien; Bruyer, Nicolas; Raffin, Guy; Baco-Antionali, Franck; Demesmay, Claire; Dugas, Vincent; Randon, Jérôme

2017-06-30

80% vinyltrimethoxysilane-based hybrid silica monoliths (80-VTMS), which have been initially developed for separation in reversed-phase liquid chromatography, have been investigated in high pressure gas chromatography separations (carrier gas pressure up to 60bar) and compared to silica monolithic columns. The behavior of both silica and 80-VTMS monolithic columns was investigated using helium, nitrogen and carbon dioxide as carrier gas. The efficiency of 80-VTMS monolithic columns was shown to vary differently than silica monolithic columns according to the temperature and the carrier gas used. Carrier gas nature was a significant parameter on the retention for both silica and vinyl columns in relation to its adsorption onto the stationary phase in such high pressure conditions. The comparison of retention and selectivity between 80-VTMS monoliths and silica was performed under helium using the logarithm of the retention factor according to the number of carbon atoms combined to Kovats indexes. The very good performances of these columns were demonstrated, allowing the separation of 8 compounds in less than 1min. Copyright © 2017 Elsevier B.V. All rights reserved.

Carrier thermalization dynamics in single zincblende and wurtzite InP Nanowires.

PubMed

Wang, Yuda; Jackson, Howard E; Smith, Leigh M; Burgess, Tim; Paiman, Suriati; Gao, Qiang; Tan, Hark Hoe; Jagadish, Chennupati

2014-12-10

Using transient Rayleigh scattering (TRS) measurements, we obtain photoexcited carrier thermalization dynamics for both zincblende (ZB) and wurtzite (WZ) InP single nanowires (NW) with picosecond resolution. A phenomenological fitting model based on direct band-to-band transition theory is developed to extract the electron-hole-plasma density and temperature as a function of time from TRS measurements of single nanowires, which have complex valence band structures. We find that the thermalization dynamics of hot carriers depends strongly on material (GaAs NW vs InP NW) and less strongly on crystal structure (ZB vs WZ). The thermalization dynamics of ZB and WZ InP NWs are similar. But a comparison of the thermalization dynamics in ZB and WZ InP NWs with ZB GaAs NWs reveals more than an order of magnitude slower relaxation for the InP NWs. We interpret these results as reflecting their distinctive phonon band structures that lead to different hot phonon effects. Knowledge of hot carrier thermalization dynamics is an essential component for effective incorporation of nanowire materials into electronic devices.

Time-resolved correlative optical microscopy of charge-carrier transport, recombination, and space-charge fields in CdTe heterostructures

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

Kuciauskas, Darius; Myers, Thomas H.; Barnes, Teresa M.

From time- and spatially resolved optical measurements, we show that extended defects can have a large effect on the charge-carrier recombination in II-VI semiconductors. In CdTe double heterostructures grown by molecular beam epitaxy on the InSb (100)-orientation substrates, we characterized the extended defects and found that near stacking faults the space-charge field extends by 2-5 μm. Charge carriers drift (with the space-charge field strength of 730-1,360 V cm -1) and diffuse (with the mobility of 260 ± 30 cm 2 V -1 s -1) toward the extended defects, where the minority-carrier lifetime is reduced from 560 ns to 0.25 ns.more » Furthermore, the extended defects are nonradiative recombination sinks that affect areas significantly larger than the typical crystalline grains in II-VI solar cells. From the correlative time-resolved photoluminescence and second-harmonic generation microscopy data, we developed a band-diagram model that can be used to analyze the impact of extended defects on solar cells and other electronic devices.« less

FKBP5 moderation of the relationship between childhood trauma and maladaptive emotion regulation strategies in adolescents.

PubMed

Halldorsdottir, Thorhildur; de Matos, Ana Paula Soares; Awaloff, Yvonne; Arnarson, Eiríkur Örn; Craighead, W Edward; Binder, Elisabeth B

2017-10-01

Maladaptive emotion regulation strategies, such as rumination and catastrophizing, are transdiagnostic risk factors for psychopathology. FK506-binding protein 51 (FKBP5) has been found to moderate the relationship between stressful life events and various psychiatric disorders. Given the cross-disorder moderation effect of FKBP5 at the diagnostic level, the aim of the current study was to examine whether the relationship between exposure to childhood trauma and transdiagnostic maladaptive emotion regulation processes would also be moderated by genetic FKBP5 variation in a community sample of adolescents. We hypothesized that adolescent carriers of the FKBP5 CATT haplotype composed of rs9296158, rs3800373, rs1360780, and rs9470080, that has been associated with increased risk for psychiatric disorders in adulthood, would also show higher levels of rumination and catastrophizing. Participants included 1345 genotyped adolescents (M age =13.95, 64.2% female; 100% European Caucasians of Portuguese descent) who completed self-report measures on exposure to childhood trauma and emotion regulation strategies. Genotypes of rs9296158, rs3800373, rs1360780, and rs9470080 were used to estimate the CATT haplotype (carriers versus non-carriers). Consistent with our hypotheses and previous findings, adolescent CATT haplotype carriers with higher levels of childhood trauma endorsed higher levels of both rumination and catastrophizing compared to non-carriers. Given the association of these maladaptive emotion regulation processes and psychiatric disorders, the findings suggest possible psychological mechanisms why FKBP5 haplotype carriers exposed to childhood trauma are more vulnerable to developing a psychiatric disorder later in life. Copyright © 2017. Published by Elsevier Ltd.

Static and Dynamic Effects of Lateral Carrier Diffusion in Semiconductor Lasers

NASA Technical Reports Server (NTRS)

Li, Jian-Zhong; Cheung, Samson H.; Ning, C. Z.; Biegel, Bryan A. (Technical Monitor)

2002-01-01

Electron and hole diffusions in the plane of semiconductor quantum wells play an important part in the static and dynamic operations of semiconductor lasers. It is well known that the value of diffusion coefficients affects the threshold pumping current of a semiconductor laser. At the same time, the strength of carrier diffusion process is expected to affect the modulation bandwidth of an AC-modulated laser. It is important not only to investigate the combined DC and AC effects due to carrier diffusion, but also to separate the AC effects from that of the combined effects in order to provide design insights for high speed modulation. In this presentation, we apply a hydrodynamic model developed by the present authors recently from the semiconductor Bloch equations. The model allows microscopic calculation of the lateral carrier diffusion coefficient, which is a nonlinear function of the carrier density and plasma temperature. We first studied combined AC and DC effects of lateral carrier diffusion by studying the bandwidth dependence on diffusion coefficient at a given DC current under small signal modulation. The results show an increase of modulation bandwidth with decrease in the diffusion coefficient. We simultaneously studied the effects of nonlinearity in the diffusion coefficient. To clearly identify how much of the bandwidth increase is a result of decrease in the threshold pumping current for smaller diffusion coefficient, thus an effective increase of DC pumping, we study the bandwidth dependence on diffusion coefficient at a given relative pumping. A detailed comparison of the two cases will be presented.

Development of breast tumors in CHEK2, NBN/NBS1 and BLM mutation carriers does not commonly involve somatic inactivation of the wild-type allele.

PubMed

Suspitsin, Evgeny N; Yanus, Grigory A; Sokolenko, Anna P; Yatsuk, Olga S; Zaitseva, Olga A; Bessonov, Alexandr A; Ivantsov, Alexandr O; Heinstein, Valeria A; Klimashevskiy, Valery F; Togo, Alexandr V; Imyanitov, Evgeny N

2014-02-01

Somatic inactivation of the remaining allele is a characteristic feature of cancers arising in BRCA1 and BRCA2 mutation carriers, which determines their unprecedented sensitivity to some DNA-damaging agents. Data on tumor-specific status of the involved gene in novel varieties of hereditary breast cancer (BC) remain incomplete. We analyzed 32 tumors obtained from 30 patients with non-BRCA1/2 BC-associated germ-line mutations: 25 women were single mutation carriers (7 BLM, 15 CHEK2 and 3 NBN/NBS1) and 5 were double mutation carriers (2 BLM/BRCA1, 1 CHEK2/BLM, 1 CHEK2/BRCA1 and 1 NBN/BLM). Losses of heterozygosity affecting the wild-type allele were detected in none of the tumors from BLM mutation carriers, 3/18 (17 %) CHEK2-associated BC and 1/4 (25 %) NBN/NBS1-driven tumors. The remaining 28 BC were subjected to the sequence analysis of entire coding region of the involved gene; no somatic mutations were identified. We conclude that the tumor-specific loss of the wild-type allele is not characteristic for BC arising in CHEK2, NBN/NBS1 and BLM mutation carriers. Rarity of "second-hit" inactivation of the involved gene in CHEK2-, NBN/NBS1- and BLM-associated BC demonstrates their substantial biological difference from BRCA1/2-driven cancers and makes them poorly suitable for the clinical trials with cisplatin and PARP inhibitors.

Association of VAV2 and VAV3 polymorphisms with cardiovascular risk factors

PubMed Central

Perretta-Tejedor, Nuria; Fernández-Mateos, Javier; García-Ortiz, Luis; Gómez-Marcos, Manuel A.; Recio-Rodríguez, José I.; Agudo-Conde, Cristina; Rodriguez-Sánchez, Emiliano; Morales, Ana I.; López-Hernández, Francisco J.; López-Novoa, José M.; González-Sarmiento, Rogelio; Martínez-Salgado, Carlos

2017-01-01

Hypertension, diabetes and obesity are cardiovascular risk factors closely associated to the development of renal and cardiovascular target organ damage. VAV2 and VAV3, members of the VAV family proto-oncogenes, are guanosine nucleotide exchange factors for the Rho and Rac GTPase family, which is related with cardiovascular homeostasis. We have analyzed the relationship between the presence of VAV2 rs602990 and VAV3 rs7528153 polymorphisms with cardiovascular risk factors and target organ damage (heart, vessels and kidney) in 411 subjects. Our results show that being carrier of the T allele in VAV2 rs602990 polymorphism is associated with an increased risk of obesity, reduced levels of ankle-brachial index and diastolic blood pressure and reduced retinal artery caliber. In addition, being carrier of T allele is associated with increased risk of target organ damage in males. On the other hand, being carrier of the T allele in VAV3 rs7528153 polymorphism is associated with a decreased susceptibility of developing a pathologic state composed by the presence of hypertension, diabetes, obesity or cardiovascular damage, and with an increased risk of developing altered basal glycaemia. This is the first report showing an association between VAV2 and VAV3 polymorphisms with cardiovascular risk factors and target organ damage. PMID:28157227

Review: emerging developments in the use of bioactive glasses for treating infected prosthetic joints.

PubMed

Rahaman, Mohamed N; Bal, B Sonny; Huang, Wenhai

2014-08-01

Bacterial contamination of implanted orthopedic prostheses is a serious complication that requires prolonged systemic antibiotic therapy, major surgery to remove infected implants, bone reconstruction, and considerable morbidity. Local delivery of high doses of antibiotics using poly(methyl methacrylate) (PMMA) cement as the carrier, along with systemic antibiotics, is the standard treatment. However, PMMA is not biodegradable, and it can present a surface on which secondary bacterial infection can occur. PMMA spacers used to treat deep implant infections must be removed after resolution of the infection. Alternative carrier materials for antibiotics that could also restore deficient bone are therefore of interest. In this article, the development of bioactive glass-based materials as a delivery system for antibiotics is reviewed. Bioactive glass is osteoconductive, converts to hydroxyapatite, and heals to hard and soft tissues in vivo. Consequently, bioactive glass-based carriers can provide the combined functions of controlled local antibiotic delivery and bone restoration. Recently-developed borate bioactive glasses are of particular interest since they have controllable degradation rates coupled with desirable properties related to osteogenesis and angiogenesis. Such glasses have the potential for providing a new class of biomaterials, as substitutes for PMMA, in the treatment of deep bone infections. Copyright © 2014 Elsevier B.V. All rights reserved.

Electronic Structure and Transport in Solids from First Principles

NASA Astrophysics Data System (ADS)

Mustafa, Jamal Ibrahim

The focus of this dissertation is the determination of the electronic structure and trans- port properties of solids. We first review some of the theory and computational methodology used in the calculation of electronic structure and materials properties. Throughout the dissertation, we make extensive use of state-of-the-art software packages that implement density functional theory, density functional perturbation theory, and the GW approximation, in addition to specialized methods for interpolating matrix elements for extremely accurate results. The first application of the computational framework introduced is the determination of band offsets in semiconductor heterojunctions using a theory of quantum dipoles at the interface. This method is applied to the case of heterojunction formed between a new metastable phase of silicon, with a rhombohedral structure, and cubic silicon. Next, we introduce a novel method for the construction of localized Wannier functions, which we have named the optimized projection functions method (OPFM). We illustrate the method on a variety of systems and find that it can reliably construct localized Wannier functions with minimal user intervention. We further develop the OPFM to investigate a class of materials called topological insulators, which are insulating in the bulk but have conductive surface states. These properties are a result of a nontrivial topology in their band structure, which has interesting effects on the character of the Wannier functions. In the last sections of the main text, the noble metals are studied in great detail, including their electronic properties and carrier dynamics. In particular, we investigate, the Fermi surface properties of the noble metals, specifically electron-phonon scattering lifetimes, and subsequently the transport properties determined by carriers on the Fermi surface. To achieve this, a novel sampling technique is developed, with wide applicability to transport calculations. Additionally, the generation and transport of hot carriers is studied extensively. The distribution of hot carriers generated from the decay of plasmons is explored over a range of energy, and the transport properties, particularly the lifetimes and mean-free-paths, of the hot carriers are determined. Lastly, appendices detailing the implementation of the algorithms developed in the work is presented, along with a useful derivation of the electron-plasmon matrix elements.

BLOOD SUBSTITUTES: EVOLUTION FROM NON-CARRYING TO OXYGEN AND GAS CARRYING FLUIDS

PubMed Central

Cabrales, Pedro; Intaglietta, Marcos

2013-01-01

The development of oxygen (O2) carrying blood substitutes has evolved from the goal of replicating blood O2 transports properties to that of preserving microvascular and organ function, reducing the inherent or potential toxicity of the material used to carry O2, and treating pathologies initiated by anemia and hypoxia. Furthermore, the emphasis has shifted from blood replacement fluid to “O2 therapeutics” that restore tissue oxygenation to specific tissues regions. This review covers the different alternatives, potential and limitations of hemoglobin based O2 carriers (HBOCs) and perfluorocarbon based O2 carriers (PFCOCs), with emphasis on the physiological conditions disturbed in the situation that they will be used. It describes how concepts learned from plasma expanders without O2 carrying capacity can be applied to maintain O2 delivery and summarizes the microvascular responses due to HBOCs and PFCOCs. This review also presents alternative applications of HBOCs and PFCOCs namely: 1) How HBOC O2 affinity can be engineered to target O2 delivery to hypoxic tissues; and 2) How the high gas solubility of PFCOCs provides new opportunities for carrying, dissolving and delivering gases with biological activity. It is concluded that current blood substitutes development has amplified their applications horizon by devising therapeutic functions for oxygen carriers requiring limited O2 delivery capacity restoration. Conversely, full, blood-like O2 carrying capacity re-establishment awaits control of O2 carrier toxicity. PMID:23820271

Infusion of imaging and therapeutic molecules into the plant virus-based carrier cowpea mosaic virus: cargo-loading and delivery

PubMed Central

Yildiz, Ibrahim; Lee, Karin L.; Chen, Kevin; Shukla, Sourabh; Steinmetz, Nicole F.

2013-01-01

This work is focused on the development of a plant virus-based carrier system for cargo delivery, specifically 30 nm-sized cowpea mosaic virus (CPMV). Whereas previous reports described the engineering of CPMV through genetic or chemical modification, we report a non-covalent infusion technique that facilitates efficient cargo loading. Infusion and retention of 130–155 fluorescent dye molecules per CPMV using DAPI (4’,6-diamidino-2-phenylindole dihydrochloride), propidium iodide (3,8-diamino-5-[3-(diethylmethylammonio)propyl]-6-phenylphenanthridinium diiodide), and acridine orange (3,6-bis(dimethylamino)acridinium chloride), as well as 140 copies of therapeutic payload proflavine (PF, acridine-3,6-diamine hydrochloride), is reported. Loading is achieved through interaction of the cargo with the CPMV’s encapsidated RNA molecules. The loading mechanism is specific; empty RNA-free eCPMV nanoparticles could not be loaded. Cargo-infused CPMV nanoparticles remain chemically active, and surface lysine residues were covalent modified with dyes leading to the development of dual-functional CPMV carrier systems. We demonstrate cargo-delivery to a panel of cancer cells (cervical, breast, and colon): CPMV nanoparticles enter cells via the surface marker vimentin, the nanoparticles target the endolysosome, where the carrier is degraded and the cargo released allowing imaging and/or cell killing. In conclusion, we demonstrate cargo-infusion and delivery to cells; the methods discussed provide a useful means for functionalization of CPMV toward its application as drug and/or contrast agent delivery vehicle. PMID:23665254

Mitochondrial oxodicarboxylate carrier deficiency is associated with mitochondrial DNA depletion and spinal muscular atrophy-like disease.

PubMed

Boczonadi, Veronika; King, Martin S; Smith, Anthony C; Olahova, Monika; Bansagi, Boglarka; Roos, Andreas; Eyassu, Filmon; Borchers, Christoph; Ramesh, Venkateswaran; Lochmüller, Hanns; Polvikoski, Tuomo; Whittaker, Roger G; Pyle, Angela; Griffin, Helen; Taylor, Robert W; Chinnery, Patrick F; Robinson, Alan J; Kunji, Edmund R S; Horvath, Rita

2018-03-08

PurposeTo understand the role of the mitochondrial oxodicarboxylate carrier (SLC25A21) in the development of spinal muscular atrophy-like disease.MethodsWe identified a novel pathogenic variant in a patient by whole-exome sequencing. The pathogenicity of the mutation was studied by transport assays, computer modeling, followed by targeted metabolic testing and in vitro studies in human fibroblasts and neurons.ResultsThe patient carries a homozygous pathogenic variant c.695A>G; p.(Lys232Arg) in the SLC25A21 gene, encoding the mitochondrial oxodicarboxylate carrier, and developed spinal muscular atrophy and mitochondrial myopathy. Transport assays show that the mutation renders SLC25A21 dysfunctional and 2-oxoadipate cannot be imported into the mitochondrial matrix. Computer models of central metabolism predicted that impaired transport of oxodicarboxylate disrupts the pathways of lysine and tryptophan degradation, and causes accumulation of 2-oxoadipate, pipecolic acid, and quinolinic acid, which was confirmed in the patient's urine by targeted metabolomics. Exposure to 2-oxoadipate and quinolinic acid decreased the level of mitochondrial complexes in neuronal cells (SH-SY5Y) and induced apoptosis.ConclusionMitochondrial oxodicarboxylate carrier deficiency leads to mitochondrial dysfunction and the accumulation of oxoadipate and quinolinic acid, which in turn cause toxicity in spinal motor neurons leading to spinal muscular atrophy-like disease.GENETICS in MEDICINE advance online publication, 8 March 2018; doi:10.1038/gim.2017.251.

Development challenges of secondary and small airports in California.

DOT National Transportation Integrated Search

2012-06-01

This study investigates the development of secondary and smaller airports in California. Low-Cost Carrier (LCC) business is growing at these airports because they offer reduced operating costs, and they have adequate capacity to help LCCs avoid battl...

Development of a transportation real-time technology readiness framework.

DOT National Transportation Integrated Search

2017-03-01

The purpose of this study was to develop a proof-of-concept carrier technology readiness framework. While substantial investment has been made into the Iowa Department of Transportation (DOT) Traffic Operations Center, scant attention has been paid t...

Development, evaluation and application of performance-based brake testing technologies field test : executive summary

DOT National Transportation Integrated Search

1999-09-01

This report presents the results of the field test portion of the Development, Evaluation, and Application of Performance-Based Brake Testing Technologies sponsored by the Federal Highway Administrations (FHWA) Office of Motor Carriers.

Dominant role of many-body effects on the carrier distribution function of quantum dot lasers

NASA Astrophysics Data System (ADS)

Peyvast, Negin; Zhou, Kejia; Hogg, Richard A.; Childs, David T. D.

2016-03-01

The effects of free-carrier-induced shift and broadening on the carrier distribution function are studied considering different extreme cases for carrier statistics (Fermi-Dirac and random carrier distributions) as well as quantum dot (QD) ensemble inhomogeneity and state separation using a Monte Carlo model. Using this model, we show that the dominant factor determining the carrier distribution function is the free carrier effects and not the choice of carrier statistics. By using empirical values of the free-carrier-induced shift and broadening, good agreement is obtained with experimental data of QD materials obtained under electrical injection for both extreme cases of carrier statistics.

14 CFR 399.82 - Passing off of carrier identity by affiliation between carriers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Passing off of carrier identity by... Relating to Enforcement § 399.82 Passing off of carrier identity by affiliation between carriers. (a... points served by both carriers should preserve the identity of the individual carriers; (5) Where joint...

14 CFR 399.82 - Passing off of carrier identity by affiliation between carriers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Passing off of carrier identity by... Relating to Enforcement § 399.82 Passing off of carrier identity by affiliation between carriers. (a... points served by both carriers should preserve the identity of the individual carriers; (5) Where joint...

14 CFR 399.82 - Passing off of carrier identity by affiliation between carriers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Passing off of carrier identity by... Relating to Enforcement § 399.82 Passing off of carrier identity by affiliation between carriers. (a... points served by both carriers should preserve the identity of the individual carriers; (5) Where joint...

14 CFR 399.82 - Passing off of carrier identity by affiliation between carriers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Passing off of carrier identity by... Relating to Enforcement § 399.82 Passing off of carrier identity by affiliation between carriers. (a... points served by both carriers should preserve the identity of the individual carriers; (5) Where joint...