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1

A comparative evaluation of the effect of internet-based CME delivery format on satisfaction, knowledge and confidence  

PubMed Central

Background Internet-based instruction in continuing medical education (CME) has been associated with favorable outcomes. However, more direct comparative studies of different Internet-based interventions, instructional methods, presentation formats, and approaches to implementation are needed. The purpose of this study was to conduct a comparative evaluation of two Internet-based CME delivery formats and the effect on satisfaction, knowledge and confidence outcomes. Methods Evaluative outcomes of two differing formats of an Internet-based CME course with identical subject matter were compared. A Scheduled Group Learning format involved case-based asynchronous discussions with peers and a facilitator over a scheduled 3-week delivery period. An eCME On Demand format did not include facilitated discussion and was not based on a schedule; participants could start and finish at any time. A retrospective, pre-post evaluation study design comparing identical satisfaction, knowledge and confidence outcome measures was conducted. Results Participants in the Scheduled Group Learning format reported significantly higher mean satisfaction ratings in some areas, performed significantly higher on a post-knowledge assessment and reported significantly higher post-confidence scores than participants in the eCME On Demand format that was not scheduled and did not include facilitated discussion activity. Conclusions The findings support the instructional benefits of a scheduled delivery format and facilitated asynchronous discussion in Internet-based CME. PMID:20113493

2010-01-01

2

A comparative evaluation of the effect of internet-based CME delivery format on satisfaction, knowledge and confidence  

Microsoft Academic Search

BACKGROUND: Internet-based instruction in continuing medical education (CME) has been associated with favorable outcomes. However, more direct comparative studies of different Internet-based interventions, instructional methods, presentation formats, and approaches to implementation are needed. The purpose of this study was to conduct a comparative evaluation of two Internet-based CME delivery formats and the effect on satisfaction, knowledge and confidence outcomes. METHODS:

Vernon R Curran; Lisa J Fleet; Fran Kirby

2010-01-01

3

CME Activity Monitoring (ACCME Standards for Commercial Support 5: Content and Format Without Commercial Bias  

E-print Network

any advertisements from commercial supporter appear in the same space as the CME activity? (Essential of commercial interests engage in sales or promotional activity while in the same space of the CME ActivityCME Activity Monitoring (ACCME Standards for Commercial Support 5: Content and Format Without

4

Social Interaction and Participation: Formative Evaluation of Online CME Modules  

ERIC Educational Resources Information Center

Introduction: This exploratory study examines Canadian physicians' participation in online social activities and learning discussions, perceptions of online social closeness, barriers and motivators to participation, and perceptions of the impact of course duration and face-to-face meetings on learning. Methods: Formative evaluations were…

Guan, Jianfei; Tregonning, Sarah; Keenan, Louanne

2008-01-01

5

If formal CME is ineffective, why do physicians still participate?  

PubMed

Formal or traditional CME can be criticized because organizers often ignore adult learning principles when designing courses. Critics also suggest that formal CME courses have limited impact on attendees' behaviors and practices. The authors agree that attention must be paid to pedagogic principles to assure success of educational courses, but feel that the extant negative evidence related to the impact of formal CME is narrow in scope and of inadequate strength to seriously damn formal approaches. Survey responses were received from 853 practicing physicians who say they still regularly attend formal CME courses. They are motivated to attend to satisfy specific professional needs and for personal reasons. Formal CME is still popular despite what its critics say. The authors are convinced that attention to physicians' perceived needs, effective use of social marketing strategies, and adherence to adult learning principles can assure successful delivery of CME and that formal CME is a useful complement to physician-driven informal CME. PMID:15203529

McLeod, P J; McLeod, A H

2004-03-01

6

Global three-dimensional MHD simulation of a space weather event: CME formation, interplanetary propagation, and interaction with the magnetosphere  

NASA Astrophysics Data System (ADS)

A parallel adaptive mesh refinement (AMR) finite-volume scheme for predicting ideal MHD flows is used to simulate the initiation, structure, and evolution of a coronal mass ejection (CME) and its interaction with the magnetosphere-ionosphere system. The simulated CME is driven by a local plasma density enhancement on the solar surface with the background initial state of the corona and solar wind represented by a newly devised ``steady state'' solution. The initial solution has been constructed to provide a reasonable description of the time-averaged solar wind for conditions near solar minimum: (1) the computed magnetic field near the Sun possesses high-latitude polar coronal holes, closed magnetic field flux tubes at low latitudes, and a helmet streamer structure with a neutral line and current sheet; (2) the Archimedean spiral topology of the interplanetary magnetic field is reproduced; (3) the observed two-state nature of the solar wind is also reproduced with the simulation yielding fast and slow solar wind streams at high and low latitudes, respectively; and (4) the predicted solar wind plasma properties at 1 AU are consistent with observations. Starting with the generation of a CME at the Sun, the simulation follows the evolution of the solar wind disturbance as it evolves into a magnetic cloud and travels through interplanetary space and subsequently interacts with the terrestrial magnetosphere-ionosphere system. The density-driven CME exhibits a two-step release process, with the front of the CME rapidly accelerating following the disruption of the near-Sun closed magnetic field line structure and then moving at a nearly constant speed of ~560 km/s through interplanetary space. The CME also produces a large magnetic cloud (>100RS across) characterized by a magnetic field that smoothly rotates northward and then back again over a period of ~2 days at 1 AU. The cloud does not contain a sustained period with a strong southward component of the magnetic field, and, as a consequence, the simulated CME is somewhat ineffective in generating strong geo-magnetic activity at Earth. Nevertheless, the simulation results illustrate the potential, as well as current limitations, of the MHD-based space weather model for enhancing the understanding of coronal physics, solar wind plasma processes, magnetospheric physics, and space weather phenomena. Such models will provide the foundation for future, more comprehensive space weather prediction tools.

Groth, Clinton P. T.; De Zeeuw, Darren L.; Gombosi, Tamas I.; Powell, Kenneth G.

2000-11-01

7

A Critical Analysis of the Literature Evaluating CME.  

ERIC Educational Resources Information Center

A critical appraisal of 290 articles in the literature of continuing medical education (CME) from 1935 to 1983 assessed formats, study designs, evaluation outcomes, and collated results. It was concluded that CME could be more broadly defined, that impact on patients is disappointing, and that further research is needed to improve its…

Davis, David A.

1984-01-01

8

Controlled Delivery of Zoledronate Improved Bone Formation Locally In Vivo  

PubMed Central

Bisphosphonates (BPs) have been widely used in clinical treatment of bone diseases with increased bone resorption because of their strong affinity for bone and their inhibition of bone resorption. Recently, there has been growing interest in their improvement of bone formation. However, the effect of local controlled delivery of BPs is unclear. We used polylactide acid-glycolic acid copolymer (PLGA) as a drug carrier to deliver various doses of the bisphosphonate zoledronate (Zol) into the distal femur of 8-week-old Sprague-Dawley rats. After 6 weeks, samples were harvested and analyzed by micro-CT and histology. The average bone mineral density and mineralized bone volume fraction were higher with medium- and high-dose PLGA-Zol (30 and 300 µg Zol, respectively) than control and low-dose Zol (3 µg PLGA-Zol; p<0.05). Local controlled delivery of Zol decreased the numbers of osteoclast and increased the numbers of osteoblast. Moreover, local controlled delivery of medium- and high-dose Zol accelerated the expression of bone-formation markers. PLGA used as a drug carrier for controlled delivery of Zol may promote local bone formation. PMID:24618585

Peng, Jiang; Lu, Qiang; Wang, Yu; Wang, Aiyuan; Guo, Quanyi; Gao, Xupeng; Xu, Wenjing; Lu, Shibi

2014-01-01

9

Physician Learning and Individualized CME.  

ERIC Educational Resources Information Center

Continuing medical education (CME) should be tailored to physicians' self-planned learning and individualized instruction. Evidence suggests that physicians engage significantly in self-initiated learning projects, so CME should be geared to assist and enhance these efforts. (SK)

Richards, Robert K.

1984-01-01

10

CME Speed Activity  

NSDL National Science Digital Library

In this activity students use pictures of Coronal Mass Ejection (CME) activity near the Sun, taken by the National Aeronautics and Space Administration/European Space Agency (NASA/ESA) Solar Heliospheric Observatory (SOHO) satellite, and calculate the speed of a CME. They discover that Coronal Mass Ejections are major storms on the Sun, which can hurl billions of tons of matter into space in a matter of a few hours. Traveling at millions of kilometers per hour, some of these clouds occasionally collide with the Earth and have produced power blackouts and satellite damage. Students view pictures in which they can see material being ejected from the Sun. They are given the elapsed time between frames, and the diameter of the sun, and are asked to select a feature in the expanding gas CME and measure its distance from the Sun from one frame to the next in order to calculate the speed of that feature. Students then plot the information and answer some questions about the speed of the CME.

Susan Higley

11

CME Group: Education  

NSDL National Science Digital Library

The CME Group is the world's largest futures and options exchange, and it was formed through the merger of the Chicago Mercantile Exchange, the Chicago Board of Trade, and the New York Mercantile Exchange. Everything from T-bonds to soybeans are traded as part of their daily operations, and the "Education" section of their website is a great way to learn about such matters. In this section, visitors can view featured videos created by the CME Group which cover topics like "Trading Techniques within the Gold Market" and "Energy's Role in National Security". Moving along, the "Education Resources" area includes areas with fact sheets, videos, and daily reports on "Commodities", "Energy", "Options", "Interest Rates", and ten other areas. For students of finance, economics, and business, this site will be an invaluable resource.

12

Continuing Medical Education: What Delivery Format Do Physicians Prefer?  

ERIC Educational Resources Information Center

Background: Although physicians are in a unique position to prevent life-threatening outcomes by counseling patients to stop smoking, many of them miss the opportunity to intervene in their patients' use of tobacco. Nicotine Dependence Across the Lifespan was developed as a continuing medical education (CME) program to teach and encourage…

Stancic, Nancy; Mullen, Patricia Dolan; Prokhorov, Alexander V.; Frankowski, Ralph F.; McAlister, Alfred L.

2003-01-01

13

The Genesis Onboard CME Identification  

NASA Astrophysics Data System (ADS)

With the Genesis mission, for the first time a satellite autonomously and in real time characterized the nature of the solar wind. Measurements from the Genesis Ion Monitor (GIM) and the Genesis Electron Monitor (GEM) were passed as input to a flight software algorithm. That algorithm categorized the solar wind as coronal hole-related fast wind, interstream slow wind, or coronal mass ejection (CME). The spacecraft then exposed the associated regime-specific collector array, thereby gathering solar wind samples sorted by flow type. Because CME composition is expected to be the most highly fractionated and variable relative to the sun, we sought to avoid contaminating the coronal hole and interstream collections with CME solar wind. The algorithm design was biased in favor of easy entry into, and difficult exit from, the CME regime. As a result, the fraction of observations attributed to CME by Genesis, 23%, is likely an over-estimate of the fraction of solar wind that was in fact CME-related during the mission. In the approximately 28 months of operation, Genesis triggered CME collection 108 times. A preliminary inspection suggests that at least 20 of those autonomous CME detections were questionable. We will present a comparison of the real-time autonomous CME identifications with a retrospective analysis. Our report will give particular emphasis to comparing the bidirectional electron streaming detected on-board with that identified in post-mission analysis, and we will report the fraction of probable closed-loop field observed.

Steinberg, J. T.; Barraclough, B. L.; Wiens, R. C.; Reisenfeld, D. B.

2005-12-01

14

CME Plotting Activity  

NSDL National Science Digital Library

This is an activity about the movement of a coronal mass ejection. Learners will plot the path of two coronal mass ejections (CMEs), both the distance traveled and the increasing angular width, as they leave the Sun and travel outward through the Solar System. Then, they will sketch the path of the CMEs and identify the location on the Sun from which a CME would need to leave in order for it to hit Earth. This is the first activity in the Solar Storms and You: Exploring the Wind from the Sun educator guide.

15

The fastest CME of Cycle 23 overtakes another fast CME  

NSDL National Science Digital Library

On November 4, 2003, the Sun produced its fastest coronal mass ejection (CME) for cycle 23 out of the active region 0486 located near the southwest limb of the Sun. The CME was expelled with a speed of approximately 2700 km-s. At the time of the launch of this CME, there was another ejection in progress from the same region. The previous ejection started about 7 hours earlier with a speed of about 1000 km-s. The fastest CME overtook the previous one within 2 hours and produced a spectacular radio radiation detected by the Wind, Ulysses and Cassini spacecraft. The movie shows the radio emission and the two interacting CMEs as observed by the SOHO spacecraft.

Tom Bridgman

2004-05-23

16

The State of the Art in CME.  

ERIC Educational Resources Information Center

The author describes major trends and directions related to continuing medical education (CME). The rapid changes he observed in the state of the art in CME are presented in relation to three historical periods in the past 16 years. (SSH)

Richards, Robert K.

1983-01-01

17

Hematometra formation- a rare complication of cesarean delivery.  

PubMed

Hematometra resulting from partial or complete obstruction of lower genital tract may be congenital or acquired. Commonest congenital causes are imperforate hymen and transverse vaginal septum. Acquired causes are senile atrophy of endocervical canal, scarring of the isthmus by synechiae, radiation and endocervical malignancy or due to surgical procedures. Various surgical procedures associated with hematometra are dilatation and curettage, cone biopsy, endometrial ablation, cryocoagulation and electrocautery. Hematometra following an abortion or cesarean delivery is rare. We report a case of hematometra following obstruction of outflow tract due to prior cesarean delivery. PMID:25302239

Kaur, Gurpreet; Jain, Sandhya; Sharma, Abha; Vaid, Neelam Bala

2014-08-01

18

Hematometra Formation- A Rare Complication of Cesarean Delivery  

PubMed Central

Hematometra resulting from partial or complete obstruction of lower genital tract may be congenital or acquired. Commonest congenital causes are imperforate hymen and transverse vaginal septum. Acquired causes are senile atrophy of endocervical canal, scarring of the isthmus by synechiae, radiation and endocervical malignancy or due to surgical procedures. Various surgical procedures associated with hematometra are dilatation and curettage, cone biopsy, endometrial ablation, cryocoagulation and electrocautery. Hematometra following an abortion or cesarean delivery is rare. We report a case of hematometra following obstruction of outflow tract due to prior cesarean delivery. PMID:25302239

Kaur, Gurpreet; Sharma, Abha; Vaid, Neelam Bala

2014-01-01

19

Reflections on CME Congress 2012  

ERIC Educational Resources Information Center

This commentary reflects the author's impressions of Continuing Medical Education (CME) Congress 2012, a provocative international conference on professional development and quality improvement in the health professions that took place in Toronto, Ontario, last spring. The sessions he attended and conversations he had with other attendees were…

Knox, Alan B.

2013-01-01

20

The deflection of 2008 December 12 CME  

NASA Astrophysics Data System (ADS)

The deflection of CME, which would significant influence the CME's geoeffectiveness, is an important topic of space weather study. In this work, the deflection of 2008 December 12 CME during it propagated from the Sun to Earth will be detailed studied based on the combination of remote and in situ observations. First, the 3-dimensions parameters reconstructed by Graduated Cylindrical Shell (GCS) model based on the STEREO observations were used to study the propagation direction evolution of this CME during it propagated in near solar space. During this phase, this CME deflect from high latitude region to equator in meridian plane but propagated almost along the longitude of W7 in ecliptic plane. Further, whether this CME deflected during it propagated in interplanetary space has also been checked. Based on the remote observations, if this CME propagated radially during it propagated in interplanetary space, it may arrived the Earth and then hit the STEREO A rather than hit STEREO B. But, the in situ observations show contrary results that this CME arrived the Earth and hit the STEREO B but missed STEREO A. This result show direct evidence that this CME deflected to east in ecliptic plane during it propagated in interplanetary space. The kinematic deflection model developed by Wang et. al (2004) has been applied on this CME. The calculation results of this model correspond well with the observational results.

Shen, C.; Wang, Y.; Liu, J.; Ye, P.; Wang, S.

2010-12-01

21

Parametric Study of CME Acceleration  

NASA Astrophysics Data System (ADS)

Observations obtained by Skylab and SMM using HAO/CP (MacQueen and Fisher, 1983) and by the recent SOHO/LASCO mission (Andrews and Howard, 2001) indicate that there at two distinct types of CMEs with different kinematic characteristics. These are (a) constant velocity CMEs and (b) accelerated CMEs. Recently, Low and Zhang (2002) have proposed a theoretical model based on specific magnetic topology which could explain these two types of CME kinematic properties. This theoretical model was attested by observation (Zhang et al. 2002) and simulated by using MHD models (Liu et al. 2002). To investigate the potential mechanisms to reveal these two types of CME kinematic properties, we have used a 2 1/2-D streamer and flux-rope MHD model (Wu and Guo, 1997) by specifying the total magnetic energy content of the streamer and flux-rope system which forms a perturbation at the lower boundary. Our results show (a) that the accelerated CMEs are due solely to the flux-rope eruption which destabilizes the streamer and (b) that the constant speed CMEs are due to drainage of flux rope material with additional heat. The results also showed that the higher the magnetic energy content of the system, the higher the CME propagation speed. Work by STW and TXZ is supported by a NASA grant NAG5-12843 and CDF's work is supported by NASA Grant NAG5-12527 and the DOD University Partnering for Operational Support (UPOS) program.

Wu, S. T.; Zhang, T. X.; Fry, C. F.; Tan, A.

2003-05-01

22

Commercial Buildings Partnership Projects - Metered Data Format and Delivery  

SciTech Connect

A number of the Commercial Building Partnership Projects (CBPs) will require metering, monitoring, data analysis and verification of savings after the retrofits are complete. Although monitoring and verification (M&V) agents are free to use any metering and monitoring devices that they chose, the data they collect should be reported to Pacific Northwest National Laboratory (PNNL) in a standard format. PNNL will store the data collected in its CBP database for further use by PNNL and U.S. Department of Energy. This document describes the data storage process and the deliver format of the data from the M&V agents.

Katipamula, Srinivas

2010-11-16

23

Controlled delivery of platelet-rich plasma-derived growth factors for bone formation  

E-print Network

Controlled delivery of platelet-rich plasma-derived growth factors for bone formation Helen H. Lu,1.interscience.wiley.com). DOI: 10.1002/jbm.a.31740 Abstract: Platelet-rich plasma (PRP) represents an autolo- gous source of PRP-derived growth factors using a hydrogel carrier system. Specifically, the release of platelet

Lu, Helen H.

24

The Effect of Flexible Learning Delivery Format on Online Learners' Learning, Application, and Instructional Perception  

ERIC Educational Resources Information Center

Instructional condition has been an important area of study to improve learner satisfaction and learning outcomes within public and private organizations. Among various types of learning methods satisfying the online learner's learning styles, this study examined the effect of flexible learning delivery format on learning and application of…

Lim, Doo H.; Morris, Michael Lane

2005-01-01

25

Mechanism of Membranous Tunnelling Nanotube Formation in Viral Genome Delivery  

PubMed Central

In internal membrane-containing viruses, a lipid vesicle enclosed by the icosahedral capsid protects the genome. It has been postulated that this internal membrane is the genome delivery device of the virus. Viruses built with this architectural principle infect hosts in all three domains of cellular life. Here, using a combination of electron microscopy techniques, we investigate bacteriophage PRD1, the best understood model for such viruses, to unveil the mechanism behind the genome translocation across the cell envelope. To deliver its double-stranded DNA, the icosahedral protein-rich virus membrane transforms into a tubular structure protruding from one of the 12 vertices of the capsid. We suggest that this viral nanotube exits from the same vertex used for DNA packaging, which is biochemically distinct from the other 11. The tube crosses the capsid through an aperture corresponding to the loss of the peripentonal P3 major capsid protein trimers, penton protein P31 and membrane protein P16. The remodeling of the internal viral membrane is nucleated by changes in osmolarity and loss of capsid-membrane interactions as consequence of the de-capping of the vertices. This engages the polymerization of the tail tube, which is structured by membrane-associated proteins. We have observed that the proteo-lipidic tube in vivo can pierce the gram-negative bacterial cell envelope allowing the viral genome to be shuttled to the host cell. The internal diameter of the tube allows one double-stranded DNA chain to be translocated. We conclude that the assembly principles of the viral tunneling nanotube take advantage of proteo-lipid interactions that confer to the tail tube elastic, mechanical and functional properties employed also in other protein-membrane systems. PMID:24086111

Peralta, Bibiana; Gil-Carton, David; Castaño-Díez, Daniel; Bertin, Aurelie; Boulogne, Claire; Oksanen, Hanna M.; Bamford, Dennis H.; Abrescia, Nicola G. A.

2013-01-01

26

College of Engineering CME Chemical Engineering  

E-print Network

College of Engineering CME Chemical Engineering KEY: # = new course * = course changed = course dropped University of Kentucky 2013-2014 Undergraduate Bulletin 1 CME 006 THE ENGINEERING PROFESSION (JUNIOR AND SENIOR). (0) Activities of the Student Chapter of the American Institute of Chemical Engineers

MacAdam, Keith

27

Objective CME detection over the solar cycle  

NASA Astrophysics Data System (ADS)

We have developed a software package for 'Computer Aided CME Tracking' (CACTus), that autonomously detects CMEs in image sequences from LASCO. The crux of the CACTus software is the detection of CMEs as bright ridges in [height, time] maps using the Hough transform. The output is a list of events, similar to the classic catalogs, with principle angle, angular width and velocity estimation for each CME. In contrast to catalogs assembled by human operators, these CME detections by software can be faster and possibly also more objective, as the detection criterion is written explicitly in a program. Especially on the timescale of a solar cycle, it is questionnable whether human, visual CME detection is stable, as the operator gains experience or personnel is replaced. In this paper we overview the latest improvements of CACTUS and validate its performance by comparing the CACTus output with the classical, visually assembled CME catalogs. Discrepancies between the classical catalogs and the CACTUS catalogs are discussed. Such discrepancies highlight not only the performance of CACTUS but also the caveats of the classical catalogs. Indeed, CACTUS sometimes finds CMEs that are not listed in the catalogs or interpreted differently (eg halo CME or not). It is important to know these caveats when using the CME catalogs as input for statistical CME studies over the solar cycle. The near realtime output of the software is available on the web(http://sidc.oma.be/cactus) and is updated daily.

Robbrecht, E.; Berghmans, D.

28

Examining the value of commercially supported CME.  

PubMed

Commercial support of continuing medical education/continuing professional development (CME/CPD) is a fact of life currently, though under attack from several sources. Does it have a positive or negative value to industry, to physicians, to society, and to CME professionals? There is sufficient evidence to support positive value to industry. There is insufficient evidence to support positive or negative value to physicians or society. There is reason to continue commercial support while broadening the base of support beyond the pharmaceutical industry, not only to avoid perception of bias but also to address CME/CPD needs that do not fit in therapeutic categories. CME professionalism does not depend on commercial support. PMID:19288557

Miller, Lewis A

2009-01-01

29

CME Link to the Geomagnetic Storms  

NASA Technical Reports Server (NTRS)

The coronal mass ejection (CME) link to geomagnetic storms stems from the southward component of the interplanetary magnetic field contained in the CME flux ropes and in the sheath between the flux rope and the CME-driven shock. A typical storm-causing CME is characterized by (i) high speed, (ii) large angular width (mostly halos and partial halos), and (iii)solar source location close to the central meridian. For CMEs originating at larger central meridian distances, the storms are mainly caused by the sheath field. Both the magnetic and energy contents of the storm-producing CMEs can be traced to the magnetic structure of active regions and the free energy stored in them.

Gopalswamy, Nat

2009-01-01

30

Recent Studies on CME-streamer Interactions  

NASA Astrophysics Data System (ADS)

Previous studies have shown the importance of streamers as a host of the CME progenitor with the magnetic energy to be released, as evidenced by observations of streamer blow-out and puff CMEs. Kinks along streamers and other coronal rays have been used to infer the dynamics of CME-driven coronal shocks. The CME-streamer interaction has also been suspected to be important for the generation of some type II radio bursts. Recent studies have discovered a new wave phenomenon dubbed as ''streamer wave', which is sometimes observed in the aftermath of CME-caused streamer deflection, and defined spectral bump and break morphological features of type II radio bursts, which are due to different transits of CME-driven shocks across a dense streamer structure. In this presentation, I will focus on these recent studies of CME-streamer interactions, and discuss how we can diagnose the coronal magnetic field strength and Alfven speed along the streamer plasma sheet with the streamer wave measurement, and infer the shock electron acceleration site as well as the shock geometry using specific features in the observed type II radio bursts. I will also discuss how a streamer-shock system forms an effective magnetic collapsing trap geometry, resulting in efficient electron acceleration to account for a special group of events termed as streamer type IIs.

CHEN, Y.

2012-12-01

31

Desktop document delivery using portable document format (PDF) files and the Web.  

PubMed Central

Desktop access to electronic full-text literature was rated one of the most desirable services in a client survey conducted by the University of Washington Libraries. The University of Washington Health Sciences Libraries (UW HSL) conducted a ten-month pilot test from August 1996 to May 1997 to determine the feasibility of delivering electronic journal articles via the Internet to remote faculty. Articles were scanned into Adobe Acrobat Portable Document Format (PDF) files and delivered to individuals using Multipurpose Internet Mail Extensions (MIME) standard e-mail attachments and the Web. Participants retrieved scanned articles and used the Adobe Acrobat Reader software to view and print files. The pilot test required a special programming effort to automate the client notification and file deletion processes. Test participants were satisfied with the pilot test despite some technical difficulties. Desktop delivery is now offered as a routine delivery method from the UW HSL. PMID:9681165

Shipman, J P; Gembala, W L; Reeder, J M; Zick, B A; Rainwater, M J

1998-01-01

32

Formation of liposome by microfluidic flow focusing and its application in gene delivery  

NASA Astrophysics Data System (ADS)

We report the formation of liposomes in a simple procedure using a microfluidic hydrodynamic flow focusing method for the application in gene delivery. We fabricated microfluidic device using soft lithography and polydimethylsiloxane (PDMS) molding technique. Lipid-containing stream was surrounded by aqueous stream and liposomes were formed at the lipid-water interface. Size distribution of liposomes and zeta potential of liposome dispersion were investigated under various flow rate ratio (FRR) and processing temperature. Size distributions of liposomes were measured by dynamic light scattering (DLS), and zeta potential was measured to quantify the colloidal stability. Prepared liposomes were used as a vehicle for gene delivery, and the successful expression of delivered gene was observed by fluorescent microscope.

Wi, Rinbok; Oh, Yeonsu; Chae, Chanhee; Kim, Do Hyun

2012-06-01

33

Delivery.  

PubMed

Enthusiasm greeted the development of synthetic organic insecticides in the mid-twentieth century, only to see this give way to dismay and eventually scepticism and outright opposition by some. Regardless of how anyone feels about this issue, insecticides and other pesticides have become indispensable, which creates something of a dilemma. Possibly as a result of the shift in public attitude towards insecticides, genetic engineering of microbes was first met with scepticism and caution among scientists. Later, the development of genetically modified crop plants was met with an attitude that hardened into both acceptance and hard-core resistance. Transgenic insects, which came along at the dawn of the twenty-first century, encountered an entrenched opposition. Those of us responsible for studying the protection of crops have been affected more or less by these protagonist and antagonistic positions, and the experiences have often left one thoughtfully mystified as decisions are made by non-participants. Most of the issues boil down to concerns over delivery mechanisms. PMID:23852646

Miller, Thomas A

2013-11-01

34

Delivery  

PubMed Central

Enthusiasm greeted the development of synthetic organic insecticides in the mid-twentieth century, only to see this give way to dismay and eventually scepticism and outright opposition by some. Regardless of how anyone feels about this issue, insecticides and other pesticides have become indispensable, which creates something of a dilemma. Possibly as a result of the shift in public attitude towards insecticides, genetic engineering of microbes was first met with scepticism and caution among scientists. Later, the development of genetically modified crop plants was met with an attitude that hardened into both acceptance and hard-core resistance. Transgenic insects, which came along at the dawn of the twenty-first century, encountered an entrenched opposition. Those of us responsible for studying the protection of crops have been affected more or less by these protagonist and antagonistic positions, and the experiences have often left one thoughtfully mystified as decisions are made by non-participants. Most of the issues boil down to concerns over delivery mechanisms. © 2013 Society of Chemical Industry PMID:23852646

Miller, Thomas A

2013-01-01

35

Membrane domain formation—a key factor for targeted intracellular drug delivery  

PubMed Central

Protein molecules, toxins and viruses internalize into the cell via receptor-mediated endocytosis (RME) using specific proteins and lipids in the plasma membrane. The plasma membrane is a barrier for many pharmaceutical agents to enter into the cytoplasm of target cells. In the case of cancer cells, tissue-specific biomarkers in the plasma membrane, like cancer-specific growth factor receptors, could be excellent candidates for RME-dependent drug delivery. Recent data suggest that agent binding to these receptors at the cell surface, resulting in membrane domain formation by receptor clustering, can be used for the initiation of RME. As a result, these pharmaceutical agents are internalized into the cells and follow different routes until they reach their final intracellular targets like lysosomes or Golgi. We propose that clustering induced formation of plasma membrane microdomains enriched in receptors, sphingolipids, and inositol lipids, leads to membrane bending which functions as the onset of RME. In this review we will focus on the role of domain formation in RME and discuss potential applications for targeted intracellular drug delivery. PMID:25520666

Popov-?eleketi?, Dušan; van Bergen en Henegouwen, Paul M. P.

2014-01-01

36

Dual growth factor delivery and controlled scaffold degradation enhance in vivo bone formation by transplanted bone marrow stromal cells  

E-print Network

. Individual delivery of BMP2 or TGF-h3 resulted in negligible bone tissue formation up to 22 weeks, regardless of exogenous growth factors are typically required to obtain bone regeneration, and it is unclear why lower to be used for therapeutic bone regeneration. We tested this hypothesis by measuring bone formation by rat

Simmons, Craig A.

37

Developing Loansome Doc as a Library Resource and a CME\\/CE Program for Patrons  

Microsoft Academic Search

Portsmouth Regional Hospital has incorporated a class on basic PubMed® evidence-based searching with a presentation on retrieving articles through the National Library of Medicine's Loansome Doc document delivery system into its Continuing Medical Education Program as a 1-Category 1 CME credit and a 1.2 CE credit. This article presents the process of making a class of this nature into both

Sheila Hayes

2006-01-01

38

Solar Back-sided Halo CME - Duration: 0:13.  

NASA Video Gallery

The Sun erupted with several CMEs (coronal mass ejections) during a period just over a day (Nov. 8-9, 2012), the largest of which was a halo CME. This CME appears to have originated from an active ...

39

What flare and CME parameters control the occurrence of solar proton events?  

NASA Astrophysics Data System (ADS)

In this study we examine the occurrence probabilities of solar proton events (SPEs) and their peak fluxes depending on both flare and coronal mass ejection (CME) parameters: flare peak flux, longitude, impulsive time, CME linear speed, and angular width. For this we use the NOAA SPEs, their associated X-ray flares, and CME from 1997 to 2011. We divide the data into 16 subgroups according to the flare and CME parameters and estimate the SPE probabilities for the subgroups. The three highest probabilities are found for the following subgroups: (1) fast full halo (55.3%) and fast partial halo (42.9%) CMEs associated with strong flares from the western region and (2) slow full halo CMEs associated with strong flares from the western region (31.6%). It is noted that the events whose SPE probabilities are nearly 0% belong to the following subgroups: (1) slow and fast partial halo CMEs from the eastern region, (2) slow partial halo CMEs from the western region, and (3) slow full halo CMEs from the eastern region. These results show that important parameters to control SPE occurrences are CME linear speed, angular width, and source longitude, which can be understood by the piston-driven shock formation of fast CMEs and magnetic field connectivity from the source site to the Earth. It is also shown that when the subgroups are separately considered by flare impulsive time and source longitude, the correlation coefficients between the observed and the predicted SPE peak fluxes are greatly improved.

Park, Jinhye; Moon, Y.-J.

2014-12-01

40

Nanoparticle formation by using shellac and chitosan for a protein delivery system.  

PubMed

The potential of using two natural polymers (chitosan and shellac) for the formation of nanoparticles by the process of ionic cross-linking to encapsulate bovine serum albumin, a model protein was investigated. Depending on the concentrations of chitosan, shellac and bovine serum albumin, three physical states - nanoparticle, aggregation, and solution could be observed as a result of the electrostatic force. The formation of nanoparticles was due to the balance between the repulsion force and attractive force while the imbalance between both forces resulted in the formation of aggregation and solution. The Fourier transform infrared spectroscopy and differential scanning calorimetry were applied to prove the nanoparticle formation. The particle size was characterized by the light scattering technique and was found in the range between 100 and 300 nm. The morphology of the particles, detected by transmission electron microscopy was spherical shape. The result showed that the zeta potential of the nanoparticles possessed positive charges. The concentrations of chitosan, shellac and bovine serum albumin had an influence on the physicochemical properties of the nanoparticles such as the particle size, the zeta potential, the encapsulation, the loading efficiencies and the cumulative release. Therefore, chitosan and shellac could be used to form nanoparticles for protein delivery by the ionic cross-linking method. PMID:22568768

Kraisit, Pakorn; Limmatvapirat, Sontaya; Nunthanid, Jurairat; Sriamornsak, Pornsak; Luangtana-anan, Manee

2013-01-01

41

A Challenging Solar Eruptive Event of 18 November 2003 and the Causes of the 20 November Geomagnetic Superstorm. III. Catastrophe of the Eruptive Filament at a Magnetic Null Point and Formation of an Opposite-Handedness CME  

NASA Astrophysics Data System (ADS)

Our analysis in Papers I and II (Grechnev et al., Solar Phys. 289, 289, 2014b and Solar Phys. 289, 1279, 2014c) of the 18 November 2003 solar event responsible for the 20 November geomagnetic superstorm has revealed a complex chain of eruptions. In particular, the eruptive filament encountered a topological discontinuity located near the solar disk center at a height of about 100 Mm, bifurcated, and transformed into a large cloud, which did not leave the Sun. Concurrently, an additional CME presumably erupted close to the bifurcation region. The conjectures about the responsibility of this compact CME for the superstorm and its disconnection from the Sun are confirmed in Paper IV (Grechnev et al., Solar Phys. submitted, 2014a), which concludes about its probable spheromak-like structure. The present article confirms the presence of a magnetic null point near the bifurcation region and addresses the origin of the magnetic helicity of the interplanetary magnetic clouds and their connection to the Sun. We find that the orientation of a magnetic dipole constituted by dimmed regions with the opposite magnetic polarities away from the parent active region corresponded to the direction of the axial field in the magnetic cloud, while the pre-eruptive filament mismatched it. To combine all of the listed findings, we propose an intrinsically three-dimensional scheme, in which a spheromak-like eruption originates via the interaction of the initially unconnected magnetic fluxes of the eruptive filament and pre-existing ones in the corona. Through a chain of magnetic reconnections their positive mutual helicity was transformed into the self-helicity of the spheromak-like magnetic cloud.

Uralov, A. M.; Grechnev, V. V.; Rudenko, G. V.; Myshyakov, I. I.; Chertok, I. M.; Filippov, B. P.; Slemzin, V. A.

2014-10-01

42

3-D views of the expanding CME: from the Sun to 1AU  

NASA Astrophysics Data System (ADS)

Three-dimensional information on Coronal Mass Ejections (CMEs) can be obtained from a wide range of in-situ measurements and remote-sensing techniques. Extreme ultraviolet (EUV) and white-light imaging sensed from several vantage points can be used to infer the 3-D geometry of the different parts that constitute a CME. High-resolution and high-cadence coronal imaging provides detailed information on the formation and release phase of a magnetic flux rope, the lateral expansion of the CME and the reconfiguration of the corona associated with the effects of pressure variations and reconnection. The evolution of the CME in the interplanetary medium and the connection of its various substructures with in-situ measurements can be obtained from multi-point heliospheric imaging.

Rouillard, Alexis P.

2015-03-01

43

Learning to Collaborate: A Case Study of Performance Improvement CME  

ERIC Educational Resources Information Center

Introduction: Performance Improvement Continuing Medical Education (PI CME) is a mechanism for joining quality improvement (QI) in health care to continuing medical education (CME) systems together. Although QI practices and CME approaches have been recognized for years, what emerges from their integration is largely unfamiliar, because it…

Shershneva, Marianna B.; Mullikin, Elizabeth A.; Loose, Anne-Sophie; Olson, Curtis A.

2008-01-01

44

Curriculum Development in Medical Education: Planning a CME Activity  

E-print Network

Curriculum Development in Medical Education: Planning a CME Activity Richard F. Tischler, Jr., PhD, FACEHP Executive Director, CME University of Maryland School of Medicine #12;Curriculum Development to plan and develop this presentation #12;Professional Practice Gap Many CME activities are planned

Weber, David J.

45

Sharing Collaborative Designs of Tobacco Cessation Performance Improvement CME Projects  

ERIC Educational Resources Information Center

Introduction: Performance Improvement Continuing Medical Education (PI CME) provides an important opportunity for CME providers to combine educational and quality health care improvement methodologies. Very few CME providers take on the challenges of planning this type of intervention because it is still a new practice and there are limited…

Mullikin, Elizabeth A.; Ales, Mary W.; Cho, Jane; Nelson, Teena M.; Rodrigues, Shelly B.; Speight, Mike

2011-01-01

46

The CME Flare Arcade and the Width of the CME in the Outer Corona  

NASA Technical Reports Server (NTRS)

Moore, Sterling, & Suess (2007, ApJ, 668, 1221) present evidence that (1) a CME is typically a magnetic bubble, a low-beta gplasmoid with legs h having roughly the 3D shape of a light bulb, and (2) in the outer corona the CME plasmoid is in lateral pressure equilibrium with the ambient magnetic field. They present three CMEs observed by SOHO/LASCO, each from a very different source located near the limb. One of these CMEs came from a compact ejective eruption from a small part of a sunspot active region, another came from a large quiet-region filament eruption, and the third CME, an extremely large and fast one, was produced in tandem with an X20 flare arcade that was centered on a huge delta sunspot. Each of these CMEs had more or less the classic lightbulb silhouette and attained a constant heliocentric angular width in the outer corona. This indicates that the CME plasmoid attained lateral magnetic pressure balance with the ambient radial magnetic field in the outer corona. This lateral pressure balance, together with the standard scenario for CME production by the eruption of a sheared-core magnetic arcade, yields the following simple estimate of the strength B(sub Flare) of the magnetic field in the flare arcade produced together with the CME: B(sub Flare) 1.4(theta CME/theta Flare)sup 2 G, where theta (sub CME) is the heliocentric angular width of the CME plasmoid in the outer corona and theta (sub Flare) is the heliocentric angular width of the full-grown flare arcade. Conversely, theta (sub CME) approximately equal to (R(sub Sun)sup -1(phi(sub Flare)/1.4)sup 1/2 radians, where Flare is the magnetic flux covered by the full-grown flare arcade. In addition to presenting the three CMEs of Moore, Sterling, & Suess (2007) and their agreement with this relation between CME and Flare, we present a further empirical test of this relation. For CMEs that erupt from active regions, the co-produced flare arcade seldom if ever covers the entire active region: if AR is the total magnetic flux of the active region, Flare . AR, and we predict that CME. (R(sub Sun))sup -1(theta AR/1.4)sup 1/2 radians. For a random sample of 31 CMEs that erupted from active regions within 30 of the limb, for each CME we have measured CME from LASCO/C3 and have measured AR from a SOHO/MDI magnetogram of the source active region when it was within 30 of disk center. We find that each CME obeys the above predicted inequality, none having width greater than half of the upper bound given by theta(sub AR). Thus, an active region's magnetic flux content, together with its location on the solar disk, largely determines whether the active region can possibly produce a CME that is wide enough to intercept the Earth.

Moore, Ron; Falconer, David; Sterling, Alphonse

2008-01-01

47

Content Validation Policy for CME EFFECTIVE DATE  

E-print Network

and not a specific proprietary business interest of a commercial interest and be based on best available evidence. E must be based on evidence that is accepted within the profession of medicine as adequate justification be appropriate CME for physicians teaching in a medical school; a course in practice management would

Goodrich, Lisa V.

48

www.chop.edu/cme Second Annual  

E-print Network

www.chop.edu/cme Second Annual Diagnosis and Management of Concussion: Acute and Specialized with concussion. Sessions will provide guidelines for the evaluation and diagnosis of concussion, including strategies for managing concussions with prolonged symptoms will be reviewed in depth, including vestibular

Fang-Yen, Christopher

49

Effects of local insulin delivery on subperiosteal angiogenesis and mineralized tissue formation during fracture healing.  

PubMed

Local insulin delivery has been shown to improve osseous healing in diabetic animals. The purpose of this study was to quantify the effects of local intramedullary delivery of saline or Ultralente insulin (UL) on various fracture healing parameters using an in vivo non-diabetic BB Wistar rat model. Quantitation of local insulin levels showed a rapid release of insulin from the fractured femora, demonstrating complete release at 2 days. RT-PCR analysis revealed that the expression of early osteogenic markers (Col1?2, osteopontin) was significantly enhanced with UL treatment when compared with saline controls (p?formation. PMID:23238777

Paglia, David N; Wey, Aaron; Breitbart, Eric A; Faiwiszewski, Jonathan; Mehta, Siddhant K; Al-Zube, Loay; Vaidya, Swaroopa; Cottrell, Jessica A; Graves, Dana; Benevenia, Joseph; O'Connor, J Patrick; Lin, Sheldon S

2013-05-01

50

CHARACTERISTICS OF KINEMATICS OF A CORONAL MASS EJECTION DURING THE 2010 AUGUST 1 CME-CME INTERACTION EVENT  

SciTech Connect

We study the interaction of two successive coronal mass ejections (CMEs) during the 2010 August 1 events using STEREO/SECCHI COR and heliospheric imager (HI) data. We obtain the direction of motion for both CMEs by applying several independent reconstruction methods and find that the CMEs head in similar directions. This provides evidence that a full interaction takes place between the two CMEs that can be observed in the HI1 field of view. The full de-projected kinematics of the faster CME from Sun to Earth is derived by combining remote observations with in situ measurements of the CME at 1 AU. The speed profile of the faster CME (CME2; {approx}1200 km s{sup -1}) shows a strong deceleration over the distance range at which it reaches the slower, preceding CME (CME1; {approx}700 km s{sup -1}). By applying a drag-based model we are able to reproduce the kinematical profile of CME2, suggesting that CME1 represents a magnetohydrodynamic obstacle for CME2 and that, after the interaction, the merged entity propagates as a single structure in an ambient flow of speed and density typical for quiet solar wind conditions. Observational facts show that magnetic forces may contribute to the enhanced deceleration of CME2. We speculate that the increase in magnetic tension and pressure, when CME2 bends and compresses the magnetic field lines of CME1, increases the efficiency of drag.

Temmer, Manuela; Rollett, Tanja; Bein, Bianca; Moestl, Christian; Veronig, Astrid M.; Flor, Olga [Kanzelhoehe Observatory-IGAM, Institute of Physics, University of Graz, Universitaetsplatz 5, A-8010 Graz (Austria); Vrsnak, Bojan; Zic, Tomislav [Hvar Observatory, Faculty of Geodesy, University of Zagreb, Kaciceva 26, HR-10000 Zagreb (Croatia); De Koning, Curt A. [NOAA Space Weather Prediction Center, Boulder, CO 80305 (United States); Liu, Ying [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Bosman, Eckhard [Space Research Institute, Austrian Academy of Sciences, A-8042 Graz (Austria); Davies, Jackie A.; Bothmer, Volker [Institut fuer Astrophysik, Goettingen University, Friedrich-Hund Platz 1, D-37077 Goettingen (Germany); Harrison, Richard [RAL Space, Rutherford Appleton Laboratory, Harwell Oxford, Didcot OX11 0QX (United Kingdom); Nitta, Nariaki [Solar and Astrophysics Laboratory, Lockheed Martin Advanced Technology Centre, Palo Alto, CA 94304-1191 (United States); Bisi, Mario [Institute of Mathematics and Physics, Aberystwyth University, Ceredigion SY23 3BZ (United Kingdom); Eastwood, Jonathan; Forsyth, Robert [The Blackett Laboratory, Imperial College London, London SW7 2AZ (United Kingdom); Odstrcil, Dusan, E-mail: mat@igam.uni-graz.at [Computational and Data Sciences, George Mason University/NASA Goddard Space Flight Center, Mail Code 674, Greenbelt, MD 20771 (United States)

2012-04-10

51

Characteristics of Kinematics of a Coronal Mass Ejection during the 2010 August 1 CME-CME Interaction Event  

NASA Astrophysics Data System (ADS)

We study the interaction of two successive coronal mass ejections (CMEs) during the 2010 August 1 events using STEREO/SECCHI COR and heliospheric imager (HI) data. We obtain the direction of motion for both CMEs by applying several independent reconstruction methods and find that the CMEs head in similar directions. This provides evidence that a full interaction takes place between the two CMEs that can be observed in the HI1 field of view. The full de-projected kinematics of the faster CME from Sun to Earth is derived by combining remote observations with in situ measurements of the CME at 1 AU. The speed profile of the faster CME (CME2; ~1200 km s-1) shows a strong deceleration over the distance range at which it reaches the slower, preceding CME (CME1; ~700 km s-1). By applying a drag-based model we are able to reproduce the kinematical profile of CME2, suggesting that CME1 represents a magnetohydrodynamic obstacle for CME2 and that, after the interaction, the merged entity propagates as a single structure in an ambient flow of speed and density typical for quiet solar wind conditions. Observational facts show that magnetic forces may contribute to the enhanced deceleration of CME2. We speculate that the increase in magnetic tension and pressure, when CME2 bends and compresses the magnetic field lines of CME1, increases the efficiency of drag.

Temmer, Manuela; Vršnak, Bojan; Rollett, Tanja; Bein, Bianca; de Koning, Curt A.; Liu, Ying; Bosman, Eckhard; Davies, Jackie A.; Möstl, Christian; Žic, Tomislav; Veronig, Astrid M.; Bothmer, Volker; Harrison, Richard; Nitta, Nariaki; Bisi, Mario; Flor, Olga; Eastwood, Jonathan; Odstrcil, Dusan; Forsyth, Robert

2012-04-01

52

Morphology and density of post-CME current sheets  

E-print Network

Eruption of a coronal mass ejection (CME) drags and "opens" the coronal magnetic field, presumably leading to the formation of a large-scale current sheet and the field relaxation by magnetic reconnection. We analyze physical characteristics of ray-like coronal features formed in the aftermath of CMEs, to check if the interpretation of this phenomenon in terms of reconnecting current sheet is consistent with the observations. The study is focused on measurements of the ray width, density excess, and coronal velocity field as a function of the radial distance. The morphology of rays indicates that they occur as a consequence of Petschek-like reconnection in the large scale current sheet formed in the wake of CME. The hypothesis is supported by the flow pattern, often showing outflows along the ray, and sometimes also inflows into the ray. The inferred inflow velocities range from 3 to 30 km s$^{-1}$, consistent with the narrow opening-angle of rays, adding up to a few degrees. The density of rays is an order o...

Vršnak, B; Vuji?, E; Vourlidas, A; Ko, Y -K; Raymond, J C; Ciaravella, A; Žic, T; Webb, D F; Bemporad, A; Landini, F; Schettino, G; Jacobs, C; Suess, S T

2009-01-01

53

Morphology and Density Structure of Post-CME Current Sheets  

NASA Technical Reports Server (NTRS)

Eruption of a coronal mass ejection (CME) is believed to drag and open the coronal magnetic field, presumably leading to the formation of a large-scale current sheet and field relaxation by magnetic reconnection. This paper analyzes the physical characteristics of ray-like coronal features formed in the aftermath of CMEs, to confirm whether interpreting such phenomena in terms of a reconnecting current sheet is consistent with observations. Methods: The study focuses on UVCS/SOHO and LASCO/SOHO measurements of the ray width, density excess, and coronal velocity field as a function of the radial distance. The morphology of the rays implies that they are produced by Petschek-like reconnection in the large-scale current sheet formed in the wake of CME. The hypothesis is supported by the flow pattern, often showing outflows along the ray, and sometimes also inflows into the ray. The inferred inflow velocities range from 3 to 30 km/s, and are consistent with the narrow opening-angle of rays, which add up to a few degrees. The density of rays is an order of magnitude higher than in the ambient corona. The model results are consistent with the observations, revealing that the main cause of the density excess in rays is a transport of the dense plasma from lower to higher heights by the reconnection outflow.

Vrsnak, B.; Poletto, G.; Vujic, E.; Vourlidas, A.

2009-01-01

54

The role of antioxidants-filled HAL delivery system on the fibrous tissue formation using adult rats as a model  

Microsoft Academic Search

Fibrous tissue formation is often used as a screening method to determine biocompatibility of orthopaedic and dental implanted material. In this investigation, porous implants of hydroxyapatitelysine (HAL) delivery devices filled with Vitamin E were implanted intraperitoneally (IP) using adult male rats as a model. The fibrous tissue surrounding the implant was studied histochemically to determine the resorbability rate of the

K. Butler; H. Benghuzzi; Z. Cason; M. Tucci; A. Puckett

1997-01-01

55

Small-Angle Neutron Scattering and Spontaneous Formation of Unilamellar Vesicles: Potential Vehicles for Drug Delivery  

NASA Astrophysics Data System (ADS)

Unilamellar vesicles (ULVs) are single-bilayer shells with radii commonly between 10 and 100 nm, and are widely used as model membranes, drug delivery systems, microreactors and substrates for a variety of enzymes and proteins. A common method of making ULVs is the extrusion of multilamellar vesicles (MLVs) through synthetic membranes of known pore size. These extruded ULVs are invariably unstable and in due time, revert back to MLVs. Over the years there have been reports of the spontaneous formation of stable ULVs in surfactant, lipid, and lipid/detergent mixtures. These ULVs have sometimes been shown to be monodisperse and their radii were found, almost without exception, to vary with concentration. We have carried-out small-angle neutron scattering (SANS) experiments on a biomimetic system composed of the phospholipids dimyristoyl and dihexanoyl phosphorylcholine (DMPC and DHPC, respectively). Doping DMPC/DHPC multilamellar vesicles with either the negatively charged lipid dimyristoyl phosphorylglycerol (DMPG, net charge -1) or the divalent cation, calcium (Ca2+) leads to the spontaneous formation of monodisperse unilamellar vesicles whose radii are concentration independent, in contrast to previous experimental observations.

Katsaras, John

2004-03-01

56

Making other Earths: Dynamical Simulations of Terrestrial Planet Formation and Water Delivery  

E-print Network

We present results from 42 simulations of late stage planetary accretion, focusing on the delivery of volatiles (primarily water) to the terrestrial planets. Our simulations include both planetary "embryos" (defined as Moon to Mars sized protoplanets) and planetesimals, assuming that the embryos formed via oligarchic growth. We investigate volatile delivery as a function of Jupiter's mass, position and eccentricity, the position of the snow line, and the density (in solids) of the solar nebula. In all simulations, we form 1-4 terrestrial planets inside 2 AU, which vary in mass and volatile content. In 42 simulations we have formed 43 planets between 0.8 and 1.5 AU, including 11 "habitable" planets between 0.9 and 1.1 AU. These planets range from dry worlds to "water worlds" with 100+ oceans of water (1 ocean = 1.5x10^24 g), and vary in mass between 0.23 and 3.85 Earth masses. There is a good deal of stochastic noise in these simulations, but the most important parameter is the planetesimal mass we choose, which reflects the surface density in solids past the snow line. A high density in this region results in the formation of a smaller number of terrestrial planets with larger masses and higher water content, as compared with planets which form in systems with lower densities. We find that an eccentric Jupiter produces drier terrestrial planets with higher eccentricities than a circular one. In cases with Jupiter at 7 AU, we form what we call "super embryos," 1-2 Earth mass protoplanets which can serve as the accretion seeds for 2+ Earth mass planets with large water contents.

Sean N. Raymond; Thomas R. Quinn; Jonathan I. Lunine

2003-08-09

57

The SOHO\\/LASCO CME Catalog  

Microsoft Academic Search

Coronal mass ejections (CMEs) are routinely identified in the images of the solar corona obtained by the Solar and Heliospheric\\u000a Observatory (SOHO) mission’s Large Angle and Spectrometric Coronagraph (LASCO) since 1996. The identified CMEs are measured\\u000a and their basic attributes are cataloged in a data base known as the SOHO\\/LASCO CME Catalog. The Catalog also contains digital\\u000a data, movies, and

N. Gopalswamy; S. Yashiro; G. Michalek; G. Stenborg; A. Vourlidas; S. Freeland; R. Howard

2009-01-01

58

Translating a health behavior change intervention for delivery to 2-year college students: the importance of formative research.  

PubMed

Young adults are at risk for weight gain in the transition to independent adulthood; 2-year college students are at greater risk and understudied relative to 4-year students. This project conducted formative research for a randomized controlled weight gain prevention trial among 2-year college students, to ensure appropriateness of content and delivery of a curriculum originally developed for 4-year college students. Data were collected from community college students, faculty, and staff from October 2009 to August 2011. Work included focus groups and key informant interviews, curriculum pilot testing, and social network and support website beta testing. Based on focus groups and interviews, program content, course delivery modes, and communication channels were adjusted to meet population interests and preferences. The course was delivered successfully in pilot testing, and the website was received well by beta testers. Formative work successfully guided program adaptations to address population needs. PMID:24904699

Linde, Jennifer A; Sevcik, Sarah M; Petrich, Christine A; Gardner, Jolynn K; Laska, Melissa N; Lozano, Paula; Lytle, Leslie A

2014-06-01

59

Methods and apparatuses for reagent delivery, reactive barrier formation, and pest control  

Microsoft Academic Search

A reagent delivery method includes positioning reagent delivery tubes in contact with soil. The tubes can include a wall that is permeable to a soil-modifying reagent. The method further includes supplying the reagent in the tubes, diffusing the reagent through the permeable wall and into the soil, and chemically modifying a selected component of the soil using the reagent. The

Tyler Gilmore; Daniel I. Kaplan; George Last

2002-01-01

60

Making other earths: dynamical simulations of terrestrial planet formation and water delivery  

Microsoft Academic Search

We present results from 44 simulations of late stage planetary accretion, focusing on the delivery of volatiles (primarily water) to the terrestrial planets. Our simulations include both planetary “embryos” (defined as Moon to Mars sized protoplanets) and planetesimals, assuming that the embryos formed via oligarchic growth. We investigate volatile delivery as a function of Jupiter's mass, position and eccentricity, the

Sean N. Raymond; Thomas R. Quinn; Jonathan I. Lunine

2004-01-01

61

Facile Formation of Dynamic Hydrogel Microspheres for Triggered Growth Factor Delivery  

PubMed Central

Dynamic hydrogels have emerged as an important class of biomaterials for temporal control over growth factor delivery. In this study we formed dynamic hydrogel microspheres from protein-polymer conjugates using an aqueous two phase suspension polymerization process. The aqueous two phase suspension polymerization process enabled rapid microsphere formation without the use of an organic phase, surfactants, mechanical strain, or toxic radical initiators. The microspheres’ size distribution was modulated by varying the protein-polymer conformation in the pre-polymer solution. Notably, the protein’s ligand-induced, nanometer scale conformational change translated to maximum hydrogel volume changes of 76±10%. The magnitude of the microspheres’ volume change was tuned by varying the crosslinking time and ligand identity. After characterizing the microspheres’ dynamic properties, we encapsulated two important therapeutic proteins, vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2), in the hydrogel microspheres and characterized how the microspheres’ dynamic properties controlled their release. Significantly, the aqueous two phase suspension polymerization process enabled high encapsulation efficiencies (65.8±4.8% and 79.5±3.0% for VEGF and BMP-2, respectively). Also, the microspheres’ ligand-induced volume change triggered VEGF and BMP-2 release at specific, predetermined times. There are hundreds of proteins that undergo well characterized conformational changes that could be processed into hydrogel microspheres via aqueous two phase suspension polymerizations. Therefore, this approach could be used to form dynamic, growth factor-releasing hydrogel microspheres that respond to a broad range of specific biochemical ligands. PMID:21029793

King, William J.; Toepke, Michael W.; Murphy, William L.

2010-01-01

62

Forecasting a CME by Spectroscopic Precursor?  

NASA Astrophysics Data System (ADS)

Multi-temperature plasma flows resulting from the interaction between a mature active region (AR) inside an equatorial coronal hole (CH) are investigated. Outflow velocities observed by Hinode EIS ranged from a few to 13 km s-1 for three days at the AR’s eastern and western edges. However, on the fourth day, velocities intensified up to 20 km s-1 at the AR’s western footpoint about six hours prior to a CME. 3D MHD numerical simulations of the observed magnetic configuration of the AR-CH complex showed that the expansion of the mature AR’s loops drives persistent outflows along the neighboring CH field (Murray et al. in Solar Phys. 261, 253, 2010). Based on these simulations, intensification of outflows observed pre-eruption on the AR’s western side where same-polarity AR and CH field interface, is interpreted to be the result of the expansion of a sigmoidal AR, in particular, a flux rope containing a filament that provides stronger compression of the neighboring CH field on this side of the AR. Intensification of outflows in the AR is proposed as a new type of CME precursor.

Baker, D.; van Driel-Gesztelyi, L.; Green, L. M.

2012-02-01

63

The anatomy of an outstanding CME meeting.  

PubMed

Organizing a continuing medical education (CME) meeting should not be a casual undertaking. It requires experience, staff support, and adequate funding. The sponsoring entity should have a thorough grounding in the Accreditation Council for Continuing Medical Education mind-set, and the course should be within the mission of the organization. Needs of the potential attendees should be assessed and objectives developed to meet those needs. An evaluation process should be in place to ensure that the needs were addressed and met. Ideally, a postcourse evaluation should assess the impact of the meeting on the behavior and practice patterns of the registrants. Excellent teachers should be selected as faculty members. These educators should be given advance information about the characteristics of the attendees, their needs, and their expectations. Topics should be chosen for their relevance to the registrants, as opposed to the convenience of the faculty members. This paper deals with these issues and several related topics. It is based on the author's experience and supplemented by relevant peer-reviewed scientific literature. The CME "market" has a "caveat emptor" approach. PMID:17411871

Muroff, Lawrence R

2005-06-01

64

Evidence for multiple-antibiotic resistance in Campylobacter jejuni not mediated by CmeB or CmeF.  

PubMed

An efflux system, CmeABC, in Campylobacter jejuni was previously described, and a second efflux system, CmeDEF, has now been identified. The substrates of CmeDEF include ampicillin, ethidium bromide, acridine, sodium dodecyl sulfate (SDS), deoxycholate, triclosan, and cetrimide, but not ciprofloxacin or erythromycin. C. jejuni NCTC11168 and two efflux pump knockout strains, cmeB::Kan(r) and cmeF::Kan(r), were exposed to 0.5 to 1 microg of ciprofloxacin/ml in agar plates. All mutants arising from NCTC11168 were resistant to ciprofloxacin but not to other agents and contained a mutation resulting in the replacement of threonine 86 with isoleucine in the quinolone resistance-determining region of GyrA. Mutants with two distinct phenotypes were selected from the efflux pump knockout strains. Mutants with the first phenotype were resistant to ciprofloxacin only and had the same substitution within GyrA as the NCTC11168-derived mutants. Irrespective of the parent strain, mutants with the second phenotype were resistant to ciprofloxacin, chloramphenicol, tetracycline, ethidium bromide, acridine orange, and SDS and had no mutation in gyrA. These mutants expressed levels of the efflux pump genes cmeB and cmeF and the major outer membrane protein gene porA similar to those expressed by the respective parent strains. No mutations were detected in cmeF or cmeB. Accumulation assays revealed that the mutants accumulated lower concentrations of drug. These data suggest the involvement of a non-CmeB or -CmeF efflux pump or reduced uptake conferring multiple-antibiotic resistance, which can be selected after exposure to a fluoroquinolone. PMID:15793099

Pumbwe, Lilian; Randall, Luke P; Woodward, Martin J; Piddock, Laura J V

2005-04-01

65

Evaluating Conflicts of Interest in Research Presented in CME Venues  

ERIC Educational Resources Information Center

Introduction: There is much in the literature regarding the potential for commercial bias in clinical research and in continuing medical education (CME), but no studies were found regarding the potential for bias in reporting original research in CME venues. This pilot study investigated the presence of perceived bias in oral and print content of…

Davis, Nancy L.; Galliher, James M.; Spano, Mindy S.; Main, Deborah S.; Brannigan, Michael; Pace, Wilson D.

2008-01-01

66

Developing an Instrument to Measure Bias in CME  

ERIC Educational Resources Information Center

Introduction: The pharmaceutical industry, by funding over 60% of programs in the United States and Canada, plays a major role in continuing medical education (CME), but there are concerns about bias in such CME programs. Bias is difficult to define, and currently no tool is available to measure it. Methods: Representatives from industry and…

Takhar, Jatinder; Dixon, Dave; Donahue, Jill; Marlow, Bernard; Campbell, Craig; Silver, Ivan; Eadie, Jason; Monette, Celine; Rohan, Ivan; Sriharan, Abi; Raymond, Kathryn; Macnab, Jennifer

2007-01-01

67

Improved Cardiovascular Prevention Using Best CME Practices: A Randomized Trial  

ERIC Educational Resources Information Center

Introduction: It was hypothesized that after a continuing medical education (CME) event, practice enablers and reinforcers addressing main clinical barriers to preventive care would be more effective in improving general practitioners' (GPs) adherence to cardiovascular guidelines than a CME event only. Methods: A cluster-randomized trial was…

Laprise, Rejean; Thivierge, Robert; Gosselin, Gilbert; Bujas-Bobanovic, Maja; Vandal, Sylvie; Paquette, Daniel; Luneau, Micheline; Julien, Pierre; Goulet, Serge; Desaulniers, Jean; Maltais, Paule

2009-01-01

68

Program Registration Family Medicine/Psychiatry CME Conference  

E-print Network

Family Medicine) Credit Card: Charge $_______________ to my: MasterCard · VISA Credit CardProgram Registration Family Medicine/Psychiatry CME Conference MARCH 27, 28, 29, 2015 CME Hours TBA Family Medicine 711 Jefferson, Suite 137 Memphis, TN 38105 901-448-8006 (fax) #12;

Cui, Yan

69

Attendees' Perceptions of Commercial Influence in Noncommercially Funded CME Programs  

ERIC Educational Resources Information Center

Introduction: The controversy surrounding commercial support for continuing medical education (CME) programs has led to policy changes, but data show no significant difference in perceived bias between commercial and noncommercial CME. Indeed, what attendees perceive as commercial influence is not fully understood. We sought to clarify what…

Goldfarb, Elizabeth; Baer, Lee; Fromson, John A.; Gorrindo, Tristan; Iodice, Kristin E.; Birnbaum, Robert J.

2012-01-01

70

CME Interaction with Large-Scale Coronal Structures  

NASA Technical Reports Server (NTRS)

This talk presents some key observations that highlight the importance of CME interaction with other large scale structures such as CMEs and coronal holes . Such interactions depend on the phase of the solar cycle: during maximum, CMEs are ejected more frequently, so CME-CME interaction becomes dominant. During the rise phase, the polar coronal holes are strong, so the interaction between polar coronal holes and CMEs is important, which also leads to a possible increase in the number of interplanetary CMEs observed as magnetic clouds. During the declining phase, there are more equatorial coronal holes, so CMEs originating near these coronal holes are easily deflected. CMEs can be deflected toward and away from the Sun-Earth line resulting in interesting geospace consequences. For example, the largest geomagnetic storm of solar cycle 23 was due to a CME that was deflected towards the Sun-earth line from E22. CME deflection away from the Sun-Earth line diminishes the chance of a CME producing a geomagnetic storm. CME interaction in the coronagraphic field of view was first identified using enhanced radio emission, which is an indication of acceleration of low energy (approx.10 keV) electrons in the interaction site. CME interaction, therefore, may also have implications for proton acceleration. For example, solar energetic particle events typically occur with a higher intensity, whenever multiple CMEs occur in quick succession from the same source region. CME deflection may also have implications to the arrival of energetic particles to earth because magnetic connectivity may be changed by the interaction. I illustrate the above points using examples from SOHO, STEREO, Wind, and ACE data .

Gopalswarny, Nat

2012-01-01

71

Automated Prediction of CMEs Using Machine Learning of CME - Flare Associations  

NASA Astrophysics Data System (ADS)

Machine-learning algorithms are applied to explore the relation between significant flares and their associated CMEs. The NGDC flares catalogue and the SOHO/LASCO CME catalogue are processed to associate X and M-class flares with CMEs based on timing information. Automated systems are created to process and associate years of flare and CME data, which are later arranged in numerical-training vectors and fed to machine-learning algorithms to extract the embedded knowledge and provide learning rules that can be used for the automated prediction of CMEs. Properties representing the intensity, flare duration, and duration of decline and duration of growth are extracted from all the associated (A) and not-associated (NA) flares and converted to a numerical format that is suitable for machine-learning use. The machine-learning algorithms Cascade Correlation Neural Networks (CCNN) and Support Vector Machines (SVM) are used and compared in our work. The machine-learning systems predict, from the input of a flare’s properties, if the flare is likely to initiate a CME. Intensive experiments using Jack-knife techniques are carried out and the relationships between flare properties and CMEs are investigated using the results. The predictive performance of SVM and CCNN is analysed and recommendations for enhancing the performance are provided.

Qahwaji, R.; Colak, T.; Al-Omari, M.; Ipson, S.

2008-04-01

72

CME - Coming At You - Duration: 0:04.  

NASA Video Gallery

An oldie but goody: The September 12, 2000 coronal mass ejection (CME), which moves directly from the sun's surface toward the viewer. This was recorded by the Solar and Heliospheric Observatory (S...

73

Methods and apparatuses for reagent delivery, reactive barrier formation, and pest control  

DOEpatents

A reagent delivery method includes positioning reagent delivery tubes in contact with soil. The tubes can include a wall that is permeable to a soil-modifying reagent. The method further includes supplying the reagent in the tubes, diffusing the reagent through the permeable wall and into the soil, and chemically modifying a selected component of the soil using the reagent. The tubes can be in subsurface contact with soil, including groundwater, and can be placed with directional drilling equipment independent of groundwater well casings. The soil-modifying reagent includes a variety of gases, liquids, colloids, and adsorbents that may be reactive or non-reactive with soil components. The method may be used inter alia to form reactive barriers, control pests, and enhance soil nutrients for microbes and plants.

Gilmore, Tyler [Pasco, WA; Kaplan, Daniel I [Aiken, SC; Last, George [Richland, WA

2002-07-09

74

Stent-Based Delivery of Sirolimus Reduces Neointimal Formation in a Porcine Coronary Model  

Microsoft Academic Search

Background—The purpose of this study was to determine the efficacy of stent-based delivery of sirolimus (SRL) alone or in combination with dexamethasone (DEX) to reduce in-stent neointimal hyperplasia. SRL is a potent immunosup- pressive agent that inhibits SMC proliferation by blocking cell cycle progression. Methods and Results—Stents were coated with a nonerodable polymer containing 185 mg SRL, 350 mg DEX,

Takeshi Suzuki; Greg Kopia; Shin-ichiro Hayashi; Lynn R. Bailey; Gerard Llanos; Robert Wilensky; Bruce D. Klugherz; George Papandreou; Pallassana Narayan; Martin B. Leon; Alan C. Yeung; Fermin Tio; Philip S. Tsao; Robert Falotico; Andrew J. Carter

75

CME front and severe space weather  

NASA Astrophysics Data System (ADS)

Thanks to the work of a number of scientists who made it known that severe space weather can cause extensive social and economic disruptions in the modern high-technology society. It is therefore important to understand what determines the severity of space weather and whether it can be predicted. We present results obtained from the analysis of coronal mass ejections (CMEs), solar energetic particle (SEP) events, interplanetary magnetic field (IMF), CME-magnetosphere coupling, and geomagnetic storms associated with the major space weather events since 1998 by combining data from the ACE and GOES satellites with geomagnetic parameters and the Carrington event of 1859, the Quebec event of 1989, and an event in 1958. The results seem to indicate that (1) it is the impulsive energy mainly due to the impulsive velocity and orientation of IMF Bz at the leading edge of the CMEs (or CME front) that determine the severity of space weather. (2) CMEs having high impulsive velocity (sudden nonfluctuating increase by over 275 km s-1 over the background) caused severe space weather (SvSW) in the heliosphere (failure of the solar wind ion mode of Solar Wind Electron Proton Alpha Monitor in ACE) probably by suddenly accelerating the high-energy particles in the SEPs ahead directly or through the shocks. (3) The impact of such CMEs which also show the IMF Bz southward from the leading edge caused SvSW at the Earth including extreme geomagnetic storms of mean DstMP < -250 nT during main phases, and the known electric power outages happened during some of these SvSW events. (4) The higher the impulsive velocity, the more severe the space weather, like faster weather fronts and tsunami fronts causing more severe damage through impulsive action. (5) The CMEs having IMF Bz northward at the leading edge do not seem to cause SvSW on Earth, although, later when the IMF Bz turns southward, they can lead to super geomagnetic storms of intensity (Dstmin) less than even -400 nT.

Balan, N.; Skoug, R.; Tulasi Ram, S.; Rajesh, P. K.; Shiokawa, K.; Otsuka, Y.; Batista, I. S.; Ebihara, Y.; Nakamura, T.

2014-12-01

76

Comparisons of Remote And In-situ CME Features  

NASA Astrophysics Data System (ADS)

We present a comparison of remote and in-situ CME ejecta using data from the Ulysses and SOHO missions. Quadrature occurs when two spacecraft form a 90 degree angle with the Sun. Quadrature studies allow the comparison of visible features of limb CMEs and and in-situ ICME properties. We investigate several events, including so-called "cannibal" CMEs, and compare the relationship between CME morphology and in-situ structures such as magnetic field, composition, and plasma properties.

Reinard, Alysha; Mulligan, T.; Lynch, B.

2011-05-01

77

What Do EUV Dimmings Tell Us About CME Topology  

NASA Astrophysics Data System (ADS)

Large-scale coronal EUV dimmings develop on timescales of hours in association with a flare or filament eruption, and are known to be well correlated with coronal mass ejections (CMEs). However, it is not clear why some CMEs have dimmings and some do not, nor is it clear how these dimmings relate to CME topology. The inner coronal coverage of SDO AIA and STEREO EUVI, combined with the extended field of view of PROBA2's SWAP imager, allow us the opportunity to map the topology of a dimming region in three dimensions into an erupting CME. Although the location and extent of a dimming region appears to be the best indicator of the inner "footprint" of a CME, the correlation is far from perfect. However, dimmings can provide vital clues about the development and 3D kinematics of CMEs. This is particularly important as we are currently in an extended period where the STEREO coronagraph images are not always available and are increasingly "mirroring" LASCO images, and therefore the 3D properties of a CME will be difficult to deduce. Thus, understanding the inner coronal manifestations of a CME can provide clues to its structure and dynamics, even without multi-viewpoint coronagraph observations. We present the results of this combined analysis effort, along with a discussion of how dimmings can be used to forecast CME trajectories.

Thompson, Barbara J.; DeRosa, Marc L.; Fisher, Richard R.; Krista, Larisza D.; Kwon, Ryun Young; Mason, James P.; Mays, Mona L.; Nitta, Nariaki V.; Webb, David F.; West, Matthew J.

2015-04-01

78

Current Sheet Evolution in the Aftermath of a CME Event  

NASA Technical Reports Server (NTRS)

We report on SOHO-UVCS observations of the coronal restructuring following a Coronal Mass Ejection (CME) on November 26,2002, at the time of a SOHO-Ulysses quadrature campaign. Starting about 3 hours after a CME in the NW quadrant, UVCS began taking spectra at 1.7 solar radius, covering emission from both cool and hot plasma. Observations continued, with occasional gaps, for more than 2 days. Emission in the 974.8 Angstrom line of [Fe XVIII], indicating temperatures above 6 x 10(exp 6) K, was observed throughout the campaign in a spatially limited location. Comparison with EIT images shows the Fe XVIII emission to overlie a growing post-flare loop system formed in the aftermath of the CME. The emission most likely originates in a current sheet overlying the arcade. Analysis of the [Fe XVIII] emission allows us to infer the evolution of physical parameters in the current sheet over the entire span of our observations: in particular, we give the temperature vs. time in the current sheet and estimate the density. At the time of the quadrature, Ulysses was directly above the location of the CME and intercepted the ejecta. High ionization state Fe was detected by Ulysses-SWICS throughout the magnetic cloud associated with the CME. Both the remote and in situ observations are compared with predictions of theoretical CME models.

Bemporad, A.; Poletto, G.; Suess, S. T.; Ko, Y.-K.; Schwadron, N. A.; Elliott, H. A.; Raymond, J. C.

2005-01-01

79

Coronal Current Sheet Evolution in the Aftermath of a CME  

NASA Technical Reports Server (NTRS)

We report on SOHO-UVCS observations of coronal restructuring following a Coronal Mass Ejection (CME) on November 26, 2002, at the time of a SOHO-Ulysses quadrature campaign. Starting about 3 hours after the CME, which was directed towards Ulysses, UVCS began taking spectra at 1.7 solar radii, covering emission from both cool and hot plasma. Observations continued, with occasional gaps, for more than 2 days. Emission in the 974.8 Angstrom line of [Fe XVIII], indicating temperatures above 6x10(6) K, was observed throughout the campaign in a spatially limited location. Comparison with EIT images shows the [Fe XVIII] emission to overlie a growing post-flare loop system formed in the aftermath of the CME. The emission most likely originates in a current sheet overlying the arcade. Analysis of the [Fe XVIII] emission allows us to infer the evolution of physical parameters in the current sheet over the entire span of our observations: in particular, we give the temperature vs. time in the current sheet and estimate the density. Ulysses was directly above the location of the CME and intercepted the ejecta. High ionization state Fe was detected by SWICS throughout the magnetic cloud associated with the CME, although the rapid temporal variation suggests bursty, rather than smooth, reconnection in the coronal current sheet. Both the remote and in situ observations are compared with predictions of theoretical CME models.

Bemporad, A.; Poletto, G.; Suess, S. T.; Ko, Y.-K.; Schwadron, N. A.; Elliott, H. A.; Raymond, J. C.

2005-01-01

80

Effect of gravitational stratification on the propagation of a CME  

NASA Astrophysics Data System (ADS)

Context. Coronal mass ejections (CMEs) are the most violent phenomenon found on the Sun. One model that explains their occurrence is the flux rope ejection model. A magnetic flux rope is ejected from the solar corona and reaches the interplanetary space where it interacts with the pre-existing magnetic fields and plasma. Both gravity and the stratification of the corona affect the early evolution of the flux rope. Aims: Our aim is to study the role of gravitational stratification on the propagation of CMEs. In particular, we assess how it influences the speed and shape of CMEs and under what conditions the flux rope ejection becomes a CME or when it is quenched. Methods: We ran a set of MHD simulations that adopt an eruptive initial magnetic configuration that has already been shown to be suitable for a flux rope ejection. We varied the temperature of the backgroud corona and the intensity of the initial magnetic field to tune the gravitational stratification and the amount of ejected magnetic flux. We used an automatic technique to track the expansion and the propagation of the magnetic flux rope in the MHD simulations. From the analysis of the parameter space, we evaluate the role of gravitational stratification on the CME speed and expansion. Results: Our study shows that gravitational stratification plays a significant role in determining whether the flux rope ejection will turn into a full CME or whether the magnetic flux rope will stop in the corona. The CME speed is affected by the background corona where it travels faster when the corona is colder and when the initial magnetic field is more intense. The fastest CME we reproduce in our parameter space travels at ~850 km s-1. Moreover, the background gravitational stratification plays a role in the side expansion of the CME, and we find that when the background temperature is higher, the resulting shape of the CME is flattened more. Conclusions: Our study shows that although the initiation mechanisms of the CME are purely magnetic, the background coronal plasma plays a key role in the CME propagation, and full MHD models should be applied when one focuses especially on the production of a CME from a flux rope ejection. Movies are available in electronic form at http://www.aanda.org

Pagano, P.; Mackay, D. H.; Poedts, S.

2013-12-01

81

Suppression of FVIII Inhibitor Formation in Hemophilic Mice by Delivery of Transgene Modified Apoptotic Fibroblasts  

PubMed Central

The development of inhibitory antibodies to factor VIII (FVIII) is currently the most significant complication of FVIII replacement therapy in the management of patients with severe hemophilia A. Immune tolerance protocols for the eradication of inhibitors require daily delivery of intravenous FVIII for at least 6 months and are unsuccessful in 20–40% of treated patients. We hypothesize that tolerance can be induced more efficiently and reliably by delivery of FVIII antigen within autologous apoptotic cells (ACs). In this study, we demonstrated suppression of the T cell and inhibitor responses to FVIII by infusion of FVIII expression vector modified apoptotic syngeneic fibroblasts in both naive and preimmunized hemophilia A mice. ACs without FVIII antigen exerted modest generalized immune suppression mediated by anti-inflammatory signals. However, FVIII expressing apoptotic syngeneic fibroblasts produced much stronger antigen-specific immune suppression. Mice treated with these fibroblasts generated CD4+ T cells that suppressed the immune response to FVIII after adoptive transfer into naive recipients and antigen-specific CD4+CD25+ regulatory T cells (Tregs) that inhibited the proliferation of FVIII responsive effector T cells in vitro. These preclinical results demonstrate the potential for using FVIII vector modified autologous ACs to treat high-titer inhibitors in patients with hemophilia A. PMID:19755963

Su, Rui-Jun; Epp, Angela; Latchman, Yvette; Bolgiano, Doug; Pipe, Steven W; Josephson, Neil C

2009-01-01

82

Formation of vitamin D nanoemulsion-based delivery systems by spontaneous emulsification: factors affecting particle size and stability.  

PubMed

Oil-in-water nanoemulsions are particularly suitable for encapsulation of lipophilic nutraceuticals because of their ability to form stable and transparent delivery systems with high oral bioavailability. In this study, the influence of system composition and preparation conditions on the particle size and stability of vitamin D nanoemulsions prepared by spontaneous emulsification (SE) was investigated. SE relies on the formation of small oil droplets when an oil/surfactant mixture is titrated into an aqueous solution. The influence of oil phase composition (vitamin D and MCT), surfactant-to-oil ratio (SOR), surfactant type (Tween 20, 40, 60, 80 and 85), and stirring conditions on the initial particle size of vitamin D nanoemulsions was studied. Nanoemulsions with small droplet diameters (d<200 nm) could be formed using Tween 80 at SOR?1 at high stirring speeds (800 rpm). These systems were relatively stable to droplet growth at ambient temperatures (<10% in diameter after 1 month storage), but unstable to heating (T>80°C). The thermal stability of the nanoemulsions could be improved by adding a cosurfactant (sodium dodecyl sulphate (SDS)). The spontaneous emulsification method is simple and inexpensive to carry out and therefore has great potential for forming nanoemulsion-based delivery systems for food, personal care, and pharmaceutical applications. PMID:25308650

Guttoff, Marrisa; Saberi, Amir Hossein; McClements, David Julian

2015-03-15

83

On the relation between Solar Filament disappearances and Halo CME  

NASA Astrophysics Data System (ADS)

On the relation between solar filament disappearances and Halo CME M.M. Hussein(1) Abstract Filament eruptions, flares, and coronal mass ejections (CMEs) are the most important solar events as far as space weather effects are concerned, linking solar eruptions, major interplanetary disturbances, and geomagnetic storms. A halo CME, which is usually associated with activity near the solar disk center, has great influence on space weather because an Earthward halo CME is indicative of coronal mass and magnetic fields moving out toward the Earth, therefore likely to cause geoeffective disturbances. The majority of previous statistical studies regarding the connection between filament eruptions and CMEs because they could be detected, observed, and measured against the dark sky background. In this paper we present a comprehensive study of filament disappearances from 1996 to 2008, and Hallo CME data for the same period that presents solar cycle 23, to predict Hallo CME for the next ten years by using different statistical tools. 1. Assistant researcher Solar and Space researches Department in the National Research Institute of Astronomy and Geophysics (NRIAG)

Shaltout, Mosalam; Hussein, Magda

84

Numerical Simulation of a Slow Streamer-Blowout CME  

NASA Astrophysics Data System (ADS)

We present a 3D numerical MHD simulation of the 2008 Jun 2 gradual streamer blowout CME that had virtually no identifiable low coronal signatures. We energize the field by simple footpoint shearing along the source region's polarity inversion line and model the background solar wind structure using an ?2MK isothermal wind and a low-order potential field source surface representation of the CR2070 synoptic magnetogram. Our results show that the CME ``initiation’’ is obtained by slowly disrupting the quasi-steady-state configuration of the helmet streamer, resulting in the standard eruptive flare picture that ejects the sheared fields, but very slowly, on a relatively large scale, and with very little magnetic energy release. We obtain a relatively slow CME eruption of order the background solar wind speed and argue that these slow streamer blowout CMEs (now also known as ``stealth CMEs’’) are simply at the lowest end of the CME energy distribution. We present comparisons of the CME propagation through the corona (?15Rs) in synthetic white-light images derived from the simulation density structure with multi-spacecraft coronagraph data from STEREO/SECCHI and SOHO/LASCO.

Lynch, Benjamin J.; Masson, Sophie; Li, Yan; DeVore, C. Richard; Luhmann, Janet; Antiochos, Spiro K.

2014-06-01

85

Analyzing Reasons for Non-Adoption of Distance Delivery Formats in Occupational Therapy Assistant (OTA) Education  

ERIC Educational Resources Information Center

Though distance education formats could help address an urgent need for growth in the occupational therapy assistant (OTA) workforce, distance methods are not as accepted in these programs as they are in other professional and clinical programs. This study investigated whether beliefs and levels of experience of OTA program directors shaped their…

Gergen, Theresa; Roblyer, M. D.

2013-01-01

86

The Impact of Course Delivery Format on Wellness Patterns of University Students  

ERIC Educational Resources Information Center

University students (N = 103) enrolled in multiple wellness courses at a small northeastern public university completed a questionnaire measuring wellness patterns at the beginning and end of a wellness course delivered totally on line (web-based), in the traditional classroom, or in a mix of the two formats (blended). Attrition of participants…

Everhart, Kim; Dimon, Chelsea

2013-01-01

87

Development and Evaluation of CmeC Subunit Vaccine against Campylobacter jejuni  

PubMed Central

Campylobacter jejuni is the leading bacterial cause of human enteritis in many industrialized countries. There is no commercial vaccine against C. jejuni available to date. CmeC is an essential outer membrane component of CmeABC multidrug efflux pump that plays a critical role in antibiotic resistance and in vivo colonization of C. jejuni. CmeC is prevalent in C. jejuni strains and is dramatically induced and immunogenic in vivo. In this study, we analyzed CmeC sequence homology, examined in vitro immune protection of CmeC peptide antibodies, and produced full-length recombinant CmeC (rCmeC) for evaluating immunogenicity and protective efficacy of the CmeC subunit vaccine against C. jejuni using chicken model system. Amino acid sequences of CmeC from 24 diverse C. jejuni strains were determined and subjected to alignment, which revealed that CmeC is highly conserved in C. jejuni with a identity ranging from 97.3% to 100%. CmeC peptide antibodies inhibited the function of CmeABC efflux pump and enhanced susceptibility of C. jejuni to bile salts, the natural antimicrobial present in the intestine. Two full-length rCmeC proteins with N- or C-terminal His tag were produced in E. coli; the N-terminal His-tagged rCmeC with high purity and yield was obtained by single step affinity purification. The purified rCmeC was used in two vaccination trials using a chicken model of C. jejuni infection. Stimulation of CmeC-specific serum IgG responses via oral vaccination required immunization with higher doses of rCmeC (200?g) together with 70?g of mucosal adjuvant mLT (modified E. coli heat-labile enterotoxin). Subcutaneous vaccination of chickens with rCmeC remarkably stimulated both serum IgG and IgA responses. However, CmeC-specific intestinal secretory IgA response was not significantly stimulated regardless of vaccination regimen and the rCmeC vaccination did not confer protection against C. jejuni infection. Together, these findings provide further compelling evidence that CmeC is a promising subunit vaccine candidate against C. jejuni infection. However, the CmeC vaccination regimen should be optimized to enhance CmeC-specific mucosal immune response in for protection against C. jejuni. PMID:22140651

Zeng, Ximin; Xu, Fuzhou; Lin, Jun

2011-01-01

88

Exercise Motivation of College Students in Online, Face-to-Face, and Blended Basic Studies Physical Activity and Wellness Course Delivery Formats  

ERIC Educational Resources Information Center

Objective: The purpose of this study was to assess exercise motivation among college students self-selected into 4 online (OL) and face-to-face (F2F) basic studies' physical activity and wellness course delivery formats. Participants/Methods: Out of 1,037 enrolled students during the Spring 2009 semester, 602 responded online to demographic…

Sidman, Cara Lynn; Fiala, Kelly Ann; D'Abundo, Michelle Lee

2011-01-01

89

Effect of monoacyl phosphatidylcholine content on the formation of microemulsions and the dermal delivery of flufenamic acid.  

PubMed

The choice of appropriate excipients is crucial for the success of a dermal drug delivery system. Especially surfactants should be chosen carefully, because of their possible interactions with the skin or the applied drug. Since monoacyl phosphatidylcholine (MAPL) exhibits great emulsification properties and can be derived from natural sources, it is of great interest as surfactant in microemulsions. Therefore, the aim of the present study was to investigate the effect of the MAPL content on the formation of microemulsions. The great emulsification power of MAPL was confirmed by increased isotropic areas with increasing MAPL content. Moreover, a decrease in particle size, particle size distribution and viscosity with increasing MAPL content was determined. Besides its effects on microemulsion structure, MAPL exhibited a significant influence on the skin permeation of flufenamic acid. Interestingly, the higher the MAPL content, the lower was the skin permeation of flufenamic acid. A possible explanation might be that the hydrophilic MAPL could hinder the permeation of the lipophilic drug. In contrast, the skin permeation enhancing effects of the microemulsion with the lowest MAPL content might be attributed to formation of a patch-like structure and therefore better contact between the formulation and the skin. PMID:25542986

Hoppel, Magdalena; Juric, Sonja; Ettl, Hanna; Valenta, Claudia

2015-02-01

90

Space Weather Model of July 22-23, 2012 CME - Duration: 0:05.  

NASA Video Gallery

NASA's Space Weather Research Center modeled the July 23, 2012 CME using a modeling program called ENLIL. The CME can be seen to expand dramatically as it travels through space. By comparing how we...

91

01.22.12: SOHO's View of Earth-directed CME - Duration: 7 seconds.  

NASA Video Gallery

The Solar Heliospheric Observatory captured the coronal mass ejection (CME) in this video (which shows the sun's activity from January 19 to January 23). The CME is associate with an M8.7 class sol...

92

Validation of CME Detection Software (CACTus) by Means of Simulated Data, and Analysis of Projection Effects on CME Velocity Measurements  

NASA Astrophysics Data System (ADS)

In the context of space weather forecasting, an automated detection of coronal mass ejections (CMEs) becomes more and more important for efficiently handling a large data flow which is expected from recently-launched and future solar missions. In this paper we validate the detection software package "CACTus" by applying the program to synthetic data from our 3D time-dependent CME simulations instead of observational data. The main strength of this study is that we know in advance what should be detected. We describe the sensitivities and strengths of automated detection, more specific for the CACTus program, resulting in a better understanding of CME detection on one hand and the calibration of the CACTus software on the other hand, suggesting possible improvements of the package. In addition, the simulation is an ideal tool to investigate projection effects on CME velocity measurements.

Bonte, K.; Jacobs, C.; Robbrecht, E.; de Groof, A.; Berghmans, D.; Poedts, S.

2011-05-01

93

THE 2010 AUGUST 1 TYPE II BURST: A CME-CME INTERACTION AND ITS RADIO AND WHITE-LIGHT MANIFESTATIONS  

SciTech Connect

We present observational results of a type II burst associated with a CME-CME interaction observed in the radio and white-light (WL) wavelength range. We applied radio direction-finding techniques to observations from the STEREO and Wind spacecraft, the results of which were interpreted using WL coronagraphic measurements for context. The results of the multiple radio direction-finding techniques applied were found to be consistent both with each other and with those derived from the WL observations of coronal mass ejections (CMEs). The results suggest that the type II burst radio emission is causally related to the CMEs interaction.

Martinez Oliveros, Juan Carlos; Raftery, Claire L.; Bain, Hazel M.; Liu Ying; Bale, Stuart; Krucker, Saem [Space Sciences Laboratory, University of California, Berkeley, CA (United States); Krupar, Vratislav [Institute of Atmospheric Physics, Academy of Sciences of the Czech Republic, Prague (Czech Republic)

2012-03-20

94

Didactic CME and Practice Change: Don't Throw that Baby out Quite yet  

ERIC Educational Resources Information Center

Skepticism exists regarding the role of continuing medical education (CME) in improving physician performance. The harshest criticism has been reserved for didactic CME. Reviews of the scientific literature on the effectiveness of CME conclude that formal or didactic modes of education have little or no impact on clinical practice. This has led…

Olson, Curtis A.; Tooman, Tricia R.

2012-01-01

95

Amount of external CME in groups of specialties: a nation-wide survey among Finnish doctors  

Microsoft Academic Search

BACKGROUND: Continuing medical education (CME) is an integral part of continuing professional development and a prerequisite for good quality in health care. We aimed to describe and analyse the number of days spent in formal CME outside the workplace by specialty among Finnish doctors of working age. FINDINGS: The number of days in formal CME outside the workplace in 2005

Arja Helin-Salmivaara; Mira Kajantie; Jukka Vänskä; Hannu Halila; Taina Autti; Juha P Turunen; Amos Pasternack

2009-01-01

96

Away?from?home CME: Age and sex differences among physicians in the Dakotas  

Microsoft Academic Search

Continuing Medical Education (CME) is required for reregistration of license in many states, continued membership in several specialty societies, and maintenance of practice privileges in most hospitals. However, although CME contributes to medical practice, it also makes demands on physicians’ personal lives. To explore these demands, we investigated enrollment at 2?day CME conferences by physicians of both sexes and varying

Henry B. Slotnick; Robert R. Raszkowski; Clayton E. Jensen; Tanya A. Christman

1994-01-01

97

Obstetrician/Gynecologists and Postpartum Mental Health: Differences between CME Course Takers and Nontakers  

ERIC Educational Resources Information Center

Introduction: Continuing medical education (CME) courses are an essential component of professional development. Research indicates a continued need for understanding how and why physicians select certain CME courses, as well as the differences between CME course takers and nontakers. Purpose: Obstetrician-gynecologists (OB-GYNs) are health care…

Leddy, Meaghan A.; Farrow, Victoria A.; Joseph, Gerald F., Jr.; Schulkin, Jay

2012-01-01

98

Improving CME: Using Participant Satisfaction Measures to Specify Educational Methods  

ERIC Educational Resources Information Center

Imagine having developed a continuing medical education (CME) initiative to educate physicians on updated guidelines regarding high cholesterol in adults. This initiative consisted of didactic presentations and case-based discussions offered in 5 major US cities, followed by a Web-based enduring component to distill key points of the live…

Olivieri, Jason J.; Regala, Roderick P.

2013-01-01

99

STEREO Captures Fastest CME to Date - Duration: 0:15.  

NASA Video Gallery

This movie shows a coronal mass ejection (CME) on the sun from July 22, 2012 at 10:00 PM EDT until 2 AM on July 23 as captured by NASA's Solar TErrestrial RElations Observatory-Ahead (STEREO-A). Be...

100

Time series of a CME blasting out from the Sun  

E-print Network

#12;Time series of a CME blasting out from the Sun Composite image of the Sun in UV light with the naked eye, the Sun seems static, placid, constant. From the ground, the only notice- able variations in the Sun are its location (where will it rise and set today?) and its color (will clouds cover

Christian, Eric

101

Synthesis and characterization of PHV-block-mPEG diblock copolymer and its formation of amphiphilic nanoparticles for drug delivery.  

PubMed

Despite the recent research interest in the field of nanoparticles delivery system, their structure modification and transport behavior of various hydrophobic drugs is poorly developed. In this article the synthesis of novel amphiphilic diblock copolymer poly([R]-3-hydroxyvalerate)-block-monomethoxy poly(ethylene glycol) (PHV-block-mPEG) was undertaken by modifying the structure of biodegradable and hydrophobic poly([R]-3-hydroxyvalerate) (PHV) with hydrophilic monomethoxy poly(ethylene glycol) (mPEG). The chemical combination of the two blocks was carried out in the melt using bis(2-ethylhexanoate) tin as transesterification catalyst. The synthesized product was characterized by gel permeation chromatography (GPC), 1H nuclear magnetic resonance (NMR) and differential scanning calorimetry (DSC) analysis. The block copolymer self-assembled into amphiphilic nanoparticles with a core of hydrophobic PHV and a shell of hydrophilic mPEG in aqueous solution. Characterization of the nanoparticles showed the formation of discrete, spherically shaped nanoparticles with mean particle size of 200 +/- 1 nm and zeta potential of -14 +/- 1 mV. A hydrophobic drug thymoquinone was efficiently incorporated into the core hydrophobic domain of the nanoparticles and its release kinetics was studied in vitro. The amphiphilic PEGylated nanoparticles showed biocompatibility when checked in neuronal hippocampal cells of prenatal rat. Our results suggest that the amphiphilic nanoparticles with core-shell structures are potentially useful to develop novel drug carriers. PMID:22121594

Shah, Mohsin; Choi, Mun Hwan; Ullah, Najeeb; Kim, Myeong Ok; Yoon, Sung Chul

2011-07-01

102

Exercise Motivation of College Students in Online, Face-to-Face, and Blended Basic Studies Physical Activity and Wellness Course Delivery Formats  

Microsoft Academic Search

Objective: The purpose of this study was to assess exercise motivation among college students self-selected into 4 online (OL) and face-to-face (F2F) basic studies’ physical activity and wellness course delivery formats. Participants\\/Methods: Out of 1,037 enrolled students during the Spring 2009 semester, 602 responded online to demographic questions and to the Behavioural Regulation in Exercise Questionnaire, which assessed exercise motivation

Cara Lynn Sidman; Kelly Ann Fiala; Michelle Lee D’Abundo

2011-01-01

103

Coronal Magnetic Field Measurement Using CME-Driven Shock Observations  

NASA Technical Reports Server (NTRS)

Collisionless shocks form ahead of coronal mass ejections (CMEs) when the CME speed exceeds the Alfven speed of the ambient plasma in the corona and interplanetary medium. The shock stands at a distance from the CME flux rope that depends on the shock Mach number, the geometry of the driver, and the adiabatic index. While the shock ahead of the CME has been observed for a long time in the in situ data, it has been identified recently near the Sun in the coronagraphic and EUV images. Unlike in situ observations, the imaging observations are two dimensional, so one can better discern the CME-shock relationship near the Sun. Gopalswamy and Yashiro demonstrated that the coronal magnetic field can be derived from the shock standoff distance measured in coronagraphic images. The method involves measuring the standoff distance, the radius of curvature of the flux rope, and assuming the value of the adiabatic index and deriving the Alfvenic Mach number. The next step is to derive the Alfvenic Mach number from the measured shock speed and an estimate of the local solar wind speed. The final step involves deriving the magnetic field from the Alfven speed by measuring the local plasma density either from coronagraphic (polarized brightness) images or from the band-splitting of type II radio bursts. In this paper, we derive the combined magnetic field profile from near the Sun to the edge of the LASCO field of view (1.5 to 30 solar radii) and compare it with the current model profiles.

Gopalswarmy, Nat; Nitta, N.; Yashiro, S.; Makela, P.; Xie, H.; Akiyama, S.

2012-01-01

104

Automated LASCO CME Catalog for Solar Cycle 23: Are CMEs Scale Invariant?  

NASA Astrophysics Data System (ADS)

In this paper, we present the first automatically constructed LASCO coronal mass ejection (CME) catalog, a result of the application of the Computer Aided CME Tracking software (CACTus) on the LASCO archive during the interval 1997 September-2007 January. We have studied the CME characteristics and have compared them with similar results obtained by manual detection (CDAW CME catalog). On average, CACTus detects less than two events per day during solar minimum, up to eight events during maximum, nearly half of them being narrow (<20°). Assuming a correction factor, we find that the CACTus CME rate is surprisingly consistent with CME rates found during the past 30 years. The CACTus statistics show that small-scale outflow is ubiquitously observed in the outer corona. The majority of CACTus-only events are narrow transients related to previous CME activity or to intensity variations in the slow solar wind, reflecting its turbulent nature. A significant fraction (about 15%) of CACTus-only events were identified as independent events, thus not related to other CME activity. The CACTus CME width distribution is essentially scale invariant in angular span over a range of scales from 20° to 120° while previous catalogs present a broad maximum around 30°. The possibility that the size of coronal mass outflows follow a power-law distribution could indicate that no typical CME size exists, i.e., that the narrow transients are not different from the larger well defined CMEs.

Robbrecht, E.; Berghmans, D.; Van der Linden, R. A. M.

2009-02-01

105

Type II Radio Bursts as an Indicator of CME Location  

NASA Astrophysics Data System (ADS)

We examined a subset of nine low-frequency radio events with type II radio bursts that drifted below 2 megahertz and were detected by the WAVES investigation on the WIND spacecraft. For each event, we identified the associated coronal mass ejection (CME) and derived the electron density using a model of solar wind plasma frequency (fp ? 9 * ne1/2, where fp is plasma frequency in kHz and ne is electron density in cm-3) . We also used the pb_inverter program in SolarSoft developed by Howard and Hayes to examine the electron density structure. Expanding on the Van De Hulst process of inverting polarized brightness measurements, the program inverts total brightness measurements from SOHO LASCO images to extract electron density information. From the electron density inferred from radio spectra, we derived the location of the CME using five standard electron density to height models (Leblanc, 1996; Saito, 1977; Bougeret, 1984; Alvarez, 1973; and Fainberg, 1971). Using images from the LASCO instrument on SOHO and the SECCHI instrument on STEREO, we extracted locations of the leading edge of the CME and compared the heights and velocities to those found using the frequency data. For the lowest frequency events, we also compared our results to the outputs of ENLIL, a time-dependent, three-dimensional, MHD model of the heliosphere hosted by the Community Coordinated Modeling Center (CCMC) at NASA Goddard Space Flight Center.

Quirk, C. A.; St Cyr, O. C.; Henning, C.; Xie, H.; Gilbert, H. R.; Orlove, M.; Gopalswamy, N.; Odstrcil, D.

2011-12-01

106

On the Relationship between Solar Magnetic Forces and CME Momenta  

NASA Astrophysics Data System (ADS)

Free magnetic energy is the energy source of solar flares and CMEs. At the initiation of a CME, the free magnetic energy converts to kinetic energy and few other types of energy. Observable magnetic field sudden changes have been found at the onset of flares. The Lorentz force around the onset of a flare have been formulated in recent studies and can be estimated using photospheric vector magnetic field data. It is proposed that outward Lorentz force impulses could be related to CME momenta. We analyze about 30 CMEs and their source region magnetic fields. The best vector magnetic field data are observed for active regions near the center of the solar disk. We first select CMEs that appear to be halo or partial halo CMEs in the LASCO images, and then we use STEREO SECCHI COR2 white light images to estimate CME mass and speed. We then estimate the Lorentz forces in the source active regions at the flare onset using SDO HMI photosheric vector magnetic field data. We report our studies and describe our analyses.This study is under the support of NSF grants.

Li, Yan; Lynch, Ben; Sun, Xudong; Welsch, Brian T.; Bercik, David J.; Fisher, George H.

2015-04-01

107

Solar Eruption Model Relating CME Kinematics to Flare Emissions  

NASA Astrophysics Data System (ADS)

The combination of a loss-of-equilibrium coronal mass ejection (CME) model with a multi-threaded flare loop model is used to develop a model of solar eruptions. The CME kinematics, thermal energy release, and flare emissions are compared in order to understand the relationship between these properties of solar eruptions. CME accelerations and peak x-ray fluxes are modeled for many different cases, and it is found that the timing of the peak flux derivative and the peak acceleration are well correlated when the inflow Alfven Mach number is fast and the magnetic field is high. The total thermal energy release and peak soft x-ray flux are observed to have a power law relationship, where the peak flux is about equal to the thermal energy to the power of alpha (alpha is between 2.54 and 1.54, depending on the reconnection rate). This finding conflicts with theoretical underpinnings of the Neupert Effect, which assumes the soft x-ray flux is proportional to the thermal energy release.

Moats, Stephanie; Reeves, K.

2010-05-01

108

Dependence of Geomagnetic Storms on Their Associated Halo CME Parameters  

NASA Astrophysics Data System (ADS)

We compare the geoeffective parameters of halo coronal mass ejections (CMEs). We consider 50 front-side full-halo CMEs (FFH CMEs), which are from the list of Michalek, Gopalswamy, and Yashiro ( Solar Phys. 246, 399, 2007), whose asymmetric-cone model parameters and earthward-direction parameter were available. For each CME we use its projected velocity [ V p], radial velocity [ V r], angle between cone axis and sky plane [ ?] from the cone model, earthward-direction parameter [ D], source longitude [ L], and magnetic-field orientation [ M] of its CME source region. We make a simple linear-regression analysis to find out the relationship between CME parameters and Dst index. The main results are as follows: i) The combined parameters [( V r D)1/2 and V r ?] have higher correlation coefficients [cc] with the Dst index than the other parameters [ V p and V r]: cc=0.76 for ( V r D)1/2, cc=0.70 for V r ?, cc=0.55 for V r, and cc=0.17 for V p. ii) Correlation coefficients between V r ? and Dst index depend on L and M; cc=0.59 for 21 eastern events [E], cc=0.80 for 29 western events [W], cc=0.49 for 17 northward magnetic-field events [N], and cc=0.69 for 33 southward magnetic-field events [S]. iii) Super geomagnetic storms (Dst?-200 nT) only appear in the western and southward magnetic-field events. The mean absolute Dst values of geomagnetic storms (Dst?-50 nT) increase with an order of E+N, E+S, W+N, and W+S events; the mean absolute Dst value (169 nT) of W+S events is significantly larger than that (75 nT) of E+N events. Our results demonstrate that not only do the cone-model parameters together with the earthward-direction parameter improve the relationship between CME parameters and Dst index, but also the longitude and the magnetic-field orientation of a FFH CME source region play a significant role in predicting geomagnetic storms.

Lee, Jae-Ok; Moon, Y.-J.; Lee, Kyoung-Sun; Kim, R.-S.

2014-06-01

109

STUDY OF THE 2007 APRIL 20 CME-COMET INTERACTION EVENT WITH AN MHD MODEL  

SciTech Connect

This study examines the tail disconnection event on 2007 April 20 on comet 2P/Encke, caused by a coronal mass ejection (CME) at a heliocentric distance of 0.34 AU. During their interaction, both the CME and the comet are visible with high temporal and spatial resolution by the STEREO-A spacecraft. Previously, only current sheets or shocks have been accepted as possible reasons for comet tail disconnections, so it is puzzling that the CME caused this event. The MHD simulation presented in this work reproduces the interaction process and demonstrates how the CME triggered a tail disconnection in the April 20 event. It is found that the CME disturbs the comet with a combination of a 180 deg. sudden rotation of the interplanetary magnetic field (IMF), followed by a 90 deg. gradual rotation. Such an interpretation applies our understanding of solar wind-comet interactions to determine the in situ IMF orientation of the CME encountering Encke.

Jia, Y. D.; Russell, C. T.; Jian, L. K. [IGPP, University of California, Los Angeles, CA 90095 (United States); Manchester, W. B.; Cohen, O.; Hansen, K. C.; Combi, M. R.; Gombosi, T. I. [CSEM, University of Michigan, Ann Arbor, MI, 48109 (United States); Vourlidas, A. [Solar Physics Branch, Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)

2009-05-01

110

Synthetic radio maps of CME-driven shocks below 4 solar radii heliocentric distance  

Microsoft Academic Search

We present 2 1\\/2 D numerical MagnetoHydroDynamic (MHD) simulations of coronal mass ejections (CMEs) in conjunction with plasma simulations of radio emission from the CME-driven shocks. The CME-driven shock extends to an almost spherical shape during the temporal evolution of the CME. Our plasma simulations can reproduce the dynamic spectra of coronal type II radio bursts, with the frequency drift

J. M. Schmidt; N. Gopalswamy

2008-01-01

111

Novel site-specific chemical delivery system as a potential mydriatic agent: formation of phenylephrine in the iris-ciliary body from phenylephrone chemical delivery systems.  

PubMed

The objective of this study was to test the three novel ester derivatives of phenylephrone (isovaleryl, phenylacetyl, and pivalyl esters) as potential site-specific chemical delivery systems. The mydriatic effect and ocular distribution/metabolism of these compounds were studied by topical application to the eyes of normal rabbits. It was assumed that a reduction-hydrolysis sequence could produce the active phenylephrine in the iris-ciliary body tissues. All the derivatives showed a more pronounced mydriatic effect than that of phenylephrine, whereas phenylephrone was completely devoid of any mydriatic activity. Phenylacetyl ester was the most potent drug, with short duration of action, and showed maximum activity in the presence of 0.01% benzalkonium chloride without causing any visible irritation to the rabbit eye. Administration of the novel compounds to the eyes of the rabbits showed no traces of phenylephrine in the systemic circulation, contrary to topical administration of phenylephrine. Phenylephrone was detected in different compartments of the eye, whereas phenylephrine was present only in the iris-ciliary body tissues following administration of phenylacetyl ester. The conversion of phenylephrone esters to the active drug, phenylephrine, and thus their subsequent activity was dependent on the physicochemical characteristics of the drugs. The results suggest the potential use of phenylacetyl ester as a potent short-term mydriatic agent without systemic side effects. PMID:11064374

Goskonda, V R; Ghandehari, H; Reddy, I K

2001-01-01

112

Evolution of two Flaring Active Regions With CME Association  

NASA Astrophysics Data System (ADS)

We study the coronal magnetic field structure of two active regions, one during solar activity minimum (June 2007) and another one during a more active time (January 2004). The temporal evolution was explored with the help of nonlinear force-free coronal magnetic field extrapolations of SOLIS/VSM and NAOJ/SFT photospheric vector magnetograms. We study the active region NOAA 10960 observed on 2007 June 7 with three SOLIS/VSM snapshots taken during a small C1.0 flare of time cadence 10 minutes and six snapshots during a quiet period. The total magnetic energy in the active region was approximately 3 × 1025 J. Before the flare the free magnetic energy was about 5~% of the potential field energy. A part of this excess energy was released during the flare, producing almost a potential configuration at the beginning of the quiet period. The return to an almost potential structure can be assigned to a CME as recorded by the SoHO/LASCO instrument on 2007 June 07 around 10 minutes after the flare peaked, so that whatever magnetic helicity was bodily removed from the structure. This was compared with active region 10540 observed on 2004 January 18 -- 21, which was analyzed with the help of vector magnetograph data from the Solar Flare Telescope in Japan of time cadence of about 1 day. The free energy was Efree? 66~% of the total energy which was sufficiently high to power a M6.1 flare on January 20, which was associated with a CME 20 minutes later. The activity of AR 10540 was significantly higher than for AR 10960, as was the total magnetic energy. Furthermore, we found the common feature that magnetic energy accumulates before the flare/CME and a significant part of the excess energy is released during the eruption.

Thalmann, J. K.; Wiegelmann, T.

2008-12-01

113

Scientific goals of the Cooperative Multiscale Experiment (CME)  

NASA Technical Reports Server (NTRS)

Mesoscale Convective Systems (MCS) form the focus of CME. Recent developments in global climate models, the urgent need to improve the representation of the physics of convection, radiation, the boundary layer, and orography, and the surge of interest in coupling hydrologic, chemistry, and atmospheric models of various scales, have emphasized the need for a broad interdisciplinary and multi-scale approach to understanding and predicting MCS's and their interactions with processes at other scales. The role of mesoscale systems in the large-scale atmospheric circulation, the representation of organized convection and other mesoscale flux sources in terms of bulk properties, and the mutually consistent treatment of water vapor, clouds, radiation, and precipitation, are all key scientific issues concerning which CME will seek to increase understanding. The manner in which convective, mesoscale, and larger scale processes interact to produce and organize MCS's, the moisture cycling properties of MCS's, and the use of coupled cloud/mesoscale models to better understand these processes, are also major objectives of CME. Particular emphasis will be placed on the multi-scale role of MCS's in the hydrological cycle and in the production and transport of chemical trace constituents. The scientific goals of the CME consist of the following: understand how the large and small scales of motion influence the location, structure, intensity, and life cycles of MCS's; understand processes and conditions that determine the relative roles of balanced (slow manifold) and unbalanced (fast manifold) circulations in the dynamics of MCS's throughout their life cycles; assess the predictability of MCS's and improve the quantitative forecasting of precipitation and severe weather events; quantify the upscale feedback of MCS's to the large-scale environment and determine interrelationships between MCS occurrence and variations in the large-scale flow and surface forcing; provide a data base for initialization and verification of coupled regional, mesoscale/hydrologic, mesoscale/chemistry, and prototype mesoscale/cloud-resolving models for prediction of severe weather, ceilings, and visibility; provide a data base for initialization and validation of cloud-resolving models, and for assisting in the fabrication, calibration, and testing of cloud and MCS parameterization schemes; and provide a data base for validation of four dimensional data assimilation schemes and algorithms for retrieving cloud and state parameters from remote sensing instrumentation.

Cotton, William

1993-01-01

114

Particle Acceleration by Cme-driven Shock Waves  

NASA Technical Reports Server (NTRS)

In the largest solar energetic particle (SEP) events, acceleration occurs at shock waves driven out from the Sun by coronal mass ejections (CMEs). Peak particle intensities are a strong function of CME speed, although the intensities, spectra, and angular distributions of particles escaping the shock are highly modified by scattering on Alfven waves produced by the streaming particles themselves. Element abundances vary in complex ways because ions with different values of Q/A resonate with different parts of the wave spectrum, which varies with space and time. Just recently, we have begun to model these systematic variations theoretically and to explore other consequences of proton-generated waves.

Reames, Donald V.

1999-01-01

115

Energetics and Dynamics of Bipolar and Multipolar CME Source Regions  

NASA Astrophysics Data System (ADS)

We present results of a numerical experiment which tests the Aly-Sturrock limit in a fully 3-dimensional, spherical geometry. We compare two common magnetic configurations corresponding to bipolar and multipolar "active region" arcades with identical photospheric normal field distributions and applied shearing flows. The bipolar response is a smooth expansion of the stressed fields, void of any explosive behavior, whereas the multipolar configuration results in the rapid expulsion of the low-lying sheared field via the magnetic breakout mechanism for CME initiation. The critical nature of the oppositely-directed overlying field and its topological consequences is discussed in the context of the breakout model.

Lynch, B. J.; Antiochos, S. K.; DeVore, C. R.; Luhmann, J. G.

2006-12-01

116

Conducting a University Career and Technical Education Degree Program through Multiple Technology Delivery Formats: A Working Model.  

ERIC Educational Resources Information Center

The Department of Industrial Technology Education (ITE) at Indiana State University offers approximately 20 courses per semester, split equally between undergraduate and graduate courses. Although all classes are offered on campus, almost half of the ITE courses are also taught using these three alternative simultaneous delivery methods: (1) for…

Zirkle, Chris

117

Dual growth factor delivery and controlled scaffold degradation enhance in vivo bone formation by transplanted bone marrow stromal cells  

Microsoft Academic Search

Supraphysiological concentrations of exogenous growth factors are typically required to obtain bone regeneration, and it is unclear why lower levels are not effective. We hypothesized that delivery of bone progenitor cells along with appropriate combinations of growth factors and scaffold characteristics would allow physiological doses of proteins to be used for therapeutic bone regeneration. We tested this hypothesis by measuring

Craig A. Simmons; Eben Alsberg; Susan Hsiong; Woo J. Kim; David J. Mooneya

2004-01-01

118

Coronal Dimming in fe XII 195 Disk Features and Halo CME Events  

NASA Astrophysics Data System (ADS)

For this study data from seven flight missions, utilizing 15 instrument systems, were used to investigate the dynamic changes to the solar atmosphere for nine flare events occurring May through July 2012 Flare characterization ranges from M5.1 to X1.4 for 6 events where GOES data is available. Three large backside flare events associated with SEP and halo CMEs were included. Disk imagery from six Instruments observing the EUV disk in He I 304 and Fe XII (and Fe XXIV) 195 were fused together in platte-carree' format forming image sequences of the entire solar surface. A nominal rate of one full whole-Sun image per ten-minutes was used for this study. In nine of nine cases, the FeXII- FeXIV 195 disk EUV data demonstrate a large-scale, dimming feature in the first 30- 60minutes post flare. Running difference image sequences show an area of expanding reduced emission (1-4% relive to pre-flare intensity), expanding in the vicinity on the flare site. Machine-based or human techniques recognized "halo" CME transients in C2 imagery for all cases, with final expansion rates in the plane of he sky of 800-1400 km/sec . In six cases GOES, or ACE detectors showed post-flare enhancement of local protons. In one of three backside events STEREO B particle detectors found SEP levels of protons. The detection of the time, location and directional evolution of these slightly dimmed dynamic features, if proven to a general characteristic, may provide an alternative to the use of coronagraphs as a means of early detection of large, Earth-directed, CME events originating from the front of the Sun.

Fisher, R. R.; Thompson, W. T.; Rager, A. C.

2012-12-01

119

SEP Acceleration in CME Driven Shocks Using a Hybrid Code  

NASA Astrophysics Data System (ADS)

We perform hybrid simulations of a super-Alfvénic quasi-parallel shock, driven by a coronal mass ejection (CME), propagating in the outer coronal/solar wind at distances of between 3 to 6 solar radii. The hybrid treatment of the problem enables the study of the shock propagation on the ion timescale, preserving ion kinetics and allowing for a self-consistent treatment of the shock propagation and particle acceleration. The CME plasma drags the embedded magnetic field lines stretching from the sun, and propagates out into interplanetary space at a greater velocity than the in situ solar wind, driving the shock, and producing very energetic particles. Our results show that electromagnetic Alfvén waves are generated at the shock front. The waves propagate upstream of the shock and are produced by the counter-streaming ions of the solar wind plasma being reflected at the shock. A significant fraction of the particles are accelerated in two distinct phases: first, particles drift from the shock and are accelerated in the upstream region, and second, particles arriving at the shock get trapped and are accelerated at the shock front. A fraction of the particles diffused back to the shock, which is consistent with the Fermi acceleration mechanism.

Gargaté, L.; Fonseca, R. A.; Silva, L. O.; Bamford, R. A.; Bingham, R.

2014-09-01

120

Controlling Quality in CME/CPD by Measuring and Illuminating Bias  

ERIC Educational Resources Information Center

Introduction: There has been a surge of interest in the area of bias in industry-supported continuing medical education/continuing professional development (CME/CPD) activities. In 2007, we published our first study on measuring bias in CME, demonstrating that our assessment tool was valid and reliable. In light of the increasing interest in this…

Dixon, David; Takhar, Jatinder; Macnab, Jennifer; Eadie, Jason; Lockyer, Jocelyn; Stenerson, Heather; Francois, Jose; Bell, Mary; Monette, Celine; Campbell, Craig; Marlow, Bernie

2011-01-01

121

A Pilot Study of CME on Risk Management in Long-Term Care  

ERIC Educational Resources Information Center

This pilot study's purpose was to evaluate behavioral changes among medical directors and physicians following CME on risk management in long-term care (LTC) facilities. The setting was a satellite conference at the AGS Meeting Symposium 2000. CME participants included 51 medical directors, attending physicians, and nurses. Evaluations were based…

Powers, James; Pichert, James W.; Habermann, Ralf; Ribble, Rachel

2004-01-01

122

Of Horses' Mouths and Toothpick Houses. A Devil's Advocate Position vis-a-vis CME Research.  

ERIC Educational Resources Information Center

The authors argue that continuing medical education (CME) research fails to prove its effectiveness in patient outcomes, that there is no theory from which to generate measurable hypotheses and that questionable methodology, dubious applicability, and misleading conclusions pervade CME research. (SK)

Miller, Judith Ribble; Pennington, Floyd A.

1984-01-01

123

A Community-Based Trial of Online Intimate Partner Violence CME  

PubMed Central

Background: There is a broad need to improve physician continuing medical education (CME) in the management of intimate partner violence (IPV). However, there are only a few examples of successful IPV CME programs and none of these are suitable for widespread distribution. Design: Randomized, controlled trial beginning in September 2003 and ending November 2004. Data were analyzed in 2005. Setting/Participants: Fifty-two primary care physicians in small (< 8 physicians), community-based medical offices in Arizona and Missouri. Intervention: Twenty-three physicians completed a minimum of 4 hours of an asynchronous, multimedia, interactive, case-based, online CME program, which provided them flexibility in constructing their educational experience (“constructivism”). Control physicians received no CME. Main Outcome Measures: Scores on a standardized 10-scale self-reported survey of IPV knowledge, attitudes, beliefs, and self-reported behaviors (KABB) administered prior to randomization and repeated at 6 and 12 months following the CME program. Results: Use of the online CME program was associated with a significant improvement in eight of 10 KABB outcomes, including physician self-efficacy and reported IPV management practices, over the study period. These measures did not improve in the control group. Conclusion: The Internet-based CME program was clearly effective in improving long-term individual educational outcomes, including self-reported IPV practices. This type of CME may be an effective and less costly alternative to live IPV training sessions and workshops. PMID:16459218

Short, Lynn M.; Surprenant, Zita J.; Harris, John M.

2006-01-01

124

KL2/Catalyst Medical Research Investigator Training (CMeRIT) Request for Applications (RFA)  

E-print Network

KL2/Catalyst Medical Research Investigator Training (CMeRIT) Request for Applications (RFA) Due Medical Research Investigator Training (CMeRIT) award provides two years of salary support at 50 Harvard Catalyst will be tuition-free. Each awardee will also receive a small research support funding

Church, George M.

125

KELVIN-HELMHOLTZ INSTABILITY OF THE CME RECONNECTION OUTFLOW LAYER IN THE LOW CORONA  

SciTech Connect

New capabilities for studying the Sun allow us to image for the first time the magnetic Kelvin-Helmholtz (KH) instability developing at the surface of a fast coronal mass ejecta (CME) less than 150 Mm above the solar surface. We conduct a detailed observational investigation of this phenomenon, observed off the east solar limb on 2010 November 3, in the EUV with SDO/AIA. In conjunction with STEREO-B/EUVI, we derive the CME source surface position. We ascertain the timing and early evolution of the CME outflow leading to the instability onset. We perform image and spectral analysis, exploring the CME plasma structuring and its parabolic flow pattern. As we evaluate and validate the consistency of the observations with theoretical considerations and predictions, we take the view that the ejecta layer corresponds to a reconnection outflow layer surrounding the erupting flux rope, accounting for the timing, high temperature ({approx}11.6 MK), and high flow shear ({approx}680 km s{sup -1}) on the unstable CME northern flank and for the observed asymmetry between the CME flanks. From the irregular evolution of the CME flow pattern, we infer a shear gradient consistent with expected spatial flow variations across the KH-unstable flank. The KH phenomenon observed is tied to the first stage of a linked flare-CME event.

Foullon, Claire; Verwichte, Erwin [Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Nykyri, Katariina [Department of Physical Sciences, Embry-Riddle Aeronautical University, Daytona Beach, FL 32114 (United States); Aschwanden, Markus J. [Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street, Palo Alto, CA 94304 (United States); Hannah, Iain G., E-mail: claire.foullon@warwick.ac.uk [School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

2013-04-20

126

Promoting Free Online CME for Intimate Partner Violence: What Works at What Cost?  

ERIC Educational Resources Information Center

Introduction: There is a need to provide practicing physicians with training on the recognition and management of intimate partner violence (IPV). Online continuing medical education (CME) could help meet this need, but there is little information on the costs and effectiveness of promoting online CME to physicians. This lack of information may…

Harris, John M., Jr.; Novalis-Marine, Cheryl; Amend, Robert W.; Surprenant, Zita J.

2009-01-01

127

CME projection effects studied with STEREO/COR and SOHO/LASCO  

E-print Network

CME projection effects studied with STEREO/COR and SOHO/LASCO M. TEMMER, S. PREISS, A.M. VERONIG edge features in the plane-of-sky (tradi- tional CME tracking) from combined STEREO/SECCHI-SOHO- craft pairs SOHO-LASCO/STEREO-A and SOHO-LASCO/STEREO-B allows us to study the reliability of the method

Temmer Manuela

128

Implications of CME Deflections on the Habitability of Planets Around M Dwarfs  

NASA Astrophysics Data System (ADS)

Solar coronal mass ejections (CMEs) are known to produce adverse space weather effects at Earth. These effects include geomagnetically induced currents and energetic particles accelerated by CME-driven shocks. Significant non-radial motions are observed for solar CMEs with the CME path deviating as much as 30 degrees within 20 solar radii. We have developed a model, Forecasting a CME's Altered Trajectory (ForeCAT), which predicts the deflected path of a CME according to the magnetic forces of the background solar wind. In Kay et al (2013), we show that these magnetic forces cause CMEs to deflect towards the region of minimum magnetic field strength. For the Sun, this magnetic minimum corresponds to the Heliospheric Current Sheet (HCS). We predict that the Earth is most likely to be impacted by a deflected CME when its orbit brings it near the HCS. M dwarfs can have magnetic field strengths several orders of magnitude larger than the Sun which will strongly affect CME deflections. We explore stellar CME deflections with ForeCAT. We present results for M4V star V374 Peg. We determine potential impacts caused by CME deflections for a planet located within the habitable zone of V374 Peg 20-40 solar radii). We discuss future extensions as including variations in solar cycle, capturing small structures such as active regions, and extensions for other M dwarf stars.

Kay, Christina; Opher, Merav

2014-06-01

129

MHD Simulations of CME-Driven Shocks: Structures Relevant to Particle Acceleration  

NASA Astrophysics Data System (ADS)

Fast Coronal Mass Ejections (CMEs) drive strong shocks from the corona through interplanetary space where these large-scale disturbances accelerate particles typically associated with gradual events. The acceleration of solar energetic particles (SEPs) is strongly dependent on shock speed and geometry, which may exhibit significant temporal and spatial variations as the CME propagates. Here, we examine three-dimensional (3-D) magnetohydrodynamic simulations of CMEs, and find that the ambient solar wind structure strongly affects the evolution of CME-driven shocks. Variations in wind speed deform the shock front, resulting in strong meridional flows and compressions in the CME sheath. We also find that CMEs can cause stream interactions that result in high-latitude reverse shocks Sunward of the CME. Understanding and predicting such CME driven shocks is a necessary step in building a quantitative model of SEP acceleration and transport that can be used to forecast and mitigate radiation hazards.

Manchester, W. B.; Toth, G.; Sokolov, I.; Zurbuchen, T. H.; Kota, J.

2008-08-01

130

Prevalence of the Campylobacter multi-drug efflux pump (CmeABC) in Campylobacter spp. Isolated from freshly processed Turkeys  

Microsoft Academic Search

The prevalence of the Campylobacter multi-drug efflux pump (CmeABC) was evaluated in Campylobacter isolates recovered from freshly processed turkeys at two Midwestern processing plants. A total of 94 Campylobacter isolates recovered from processed turkeys were examined using polymerase chain reaction (PCR) to determine the presence of the multi-drug efflux pump genes cmeA, cmeB, and cmeC.Results from this study found that

Pamela A. Olah; Curt Doetkott; Mohamed K. Fakhr; Catherine M. Logue

2006-01-01

131

Dual delivery of rhPDGF-BB and bone marrow mesenchymal stromal cells expressing the BMP2 gene enhance bone formation in a critical-sized defect model.  

PubMed

Bone tissue healing is a dynamic, orchestrated process that relies on multiple growth factors and cell types. Platelet-derived growth factor-BB (PDGF-BB) is released from platelets at wound sites and induces cellular migration and proliferation necessary for bone regeneration in the early healing process. Bone morphogenetic protein-2 (BMP-2), the most potent osteogenic differentiation inducer, directs new bone formation at the sites of bone defects. This study evaluated a combinatorial treatment protocol of PDGF-BB and BMP-2 on bone healing in a critical-sized defect model. To mimic the bone tissue healing process, a dual delivery approach was designed to deliver the rhPDGF-BB protein transiently during the early healing phase, whereas BMP-2 was supplied by rat bone marrow stromal cells (BMSCs) transfected with an adenoviral vector containing the BMP2 gene (AdBMP2) for prolonged release throughout the healing process. In in vitro experiments, the dual delivery of rhPDGF-BB and BMP2 significantly enhanced cell proliferation. However, the osteogenic differentiation of BMSCs was significantly suppressed even though the amount of BMP-2 secreted by the AdBMP2-transfected BMSCs was not significantly affected by the rhPDGF-BB treatment. In addition, dual delivery inhibited the mRNA expression of BMP receptor type II and Noggin in BMSCs. In in vivo experiments, critical-sized calvarial defects in rats showed enhanced bone regeneration by dual delivery of autologous AdBMP2-transfected BMSCs and rhPDGF-BB in both the amount of new bone formed and the bone mineral density. These enhancements in bone regeneration were greater than those observed in the group treated with AdBMP2-transfected BMSCs alone. In conclusion, the dual delivery of rhPDGF-BB and AdBMP2-transfected BMSCs improved the quality of the regenerated bone, possibly due to the modulation of PDGF-BB on BMP-2-induced osteogenesis. PMID:23901900

Park, Shin-Young; Kim, Kyoung-Hwa; Shin, Seung-Yun; Koo, Ki-Tae; Lee, Yong-Moo; Seol, Yang-Jo

2013-11-01

132

Ion Transport in the September 24, 1998 CME Event  

NASA Technical Reports Server (NTRS)

On 24 September 1998 Earth's magnetosphere was impacted by a large CME with an associated shock front. This impact moved the magnetopause inward by several Re and pushed dayside magnetospheric boundaries anti-sunward by more than 1 Re. The resulting observations from the Polar spacecraft, which was located over the northern polar cap, show signatures of the polar cap, the cusp, and the mantle as these regions were moved across the spacecraft position. An enhanced Cleft Ion Fountain outflow was observed as Polar moved sunward towards the cusp following the shock passage. Analysis of these data shows the velocity filter/mass spectrometer nature of the CIF in association with anti-sunward convection. These signatures are used to investigate time scales for reconnection, energy transfer to the Ionosphere, and CIF outflow generation.

Chandler, M. O.; Craven, P. D.

1999-01-01

133

CME Interaction with Coronal Holes and Their Interplanetary Consequences  

NASA Technical Reports Server (NTRS)

A significant number of interplanetary (IP) shocks (-17%) during cycle 23 were not followed by drivers. The number of such "driverless" shocks steadily increased with the solar cycle with 15%, 33%, and 52% occurring in the rise, maximum, and declining phase of the solar cycle. The solar sources of 15% of the driverless shocks were very close the central meridian of the Sun (within approx.15deg), which is quite unexpected. More interestingly, all the driverless shocks with their solar sources near the solar disk center occurred during the declining phase of solar cycle 23. When we investigated the coronal environment of the source regions of driverless shocks, we found that in each case there was at least one coronal hole nearby suggesting that the coronal holes might have deflected the associated coronal mass ejections (CMEs) away from the Sun-Earth line. The presence of abundant low-latitude coronal holes during the declining phase further explains why CMEs originating close to the disk center mimic the limb CMEs, which normally lead to driverless shocks due to purely geometrical reasons. We also examined the solar source regions of shocks with drivers. For these, the coronal holes were located such that they either had no influence on the CME trajectories. or they deflected the CMEs towards the Sun-Earth line. We also obtained the open magnetic field distribution on the Sun by performing a potential field source surface extrapolation to the corona. It was found that the CMEs generally move away from the open magnetic field regions. The CME-coronal hole interaction must be widespread in the declining phase, and may have a significant impact on the geoeffectiveness of CMEs.

Gopalswamy, N.; Makela, P.; Xie, H.; Akiyama, S.; Yashiro, S.

2008-01-01

134

Contribution of the Multidrug Efflux Transporter CmeABC to Antibiotic Resistance in Different Campylobacter Species  

PubMed Central

Abstract CmeABC, a multidrug efflux system in Campylobacter jejuni, plays an important role in the resistance to different antimicrobials and toxic compounds. Although this efflux system has been well characterized in C. jejuni and to a less extent in C. coli, it is unknown if CmeABC homologs are functional in other Campylobacter spp. In this study, the cmeABC homologs were identified and functionally characterized in five Campylobacter species including C. jejuni, C. coli, C. lari, C. upsaliensis, and C. fetus. Our results indicated that cmeABC is present in all five Campylobacter spp. and the genomic organization of this efflux operon is similar among the Campylobacter spp. Insertional mutagenesis of cmeB increased the susceptibilities of all the five Campylobacter spp. to structurally diverse antimicrobials. Together, these results indicated that the CmeABC efflux system is conserved at both the genomic and functional levels in all five Campylobacter spp. examined in this study, further highlighting the significant role of CmeABC in Campylobacter pathobiology. PMID:19785541

Guo, Baoqing; Lin, Jun; Reynolds, Donald L.

2010-01-01

135

Radio Observations of the CME-poor region AR2192: a type II burst with no CME driver  

NASA Astrophysics Data System (ADS)

The remarkable sunspot group NOAA AR 2192 (October 2014) produced X-class flares without CMEs, and in general was large and powerful but with little heliospheric interaction. We discuss radio perspectives on the development of this region. In particular there were decametric type II bursts observed in association with jet-like flares SOL2014-10-21T12:28 (C4.4) and SOL2014-10-21T13:38 (M1.2), as first noted in the Glasgow Callisto observatory and confirmed via the Meudon decametric array. In cases such as this, the global coronal wave responsible for the type II emission seems to originate from an ejection of material flowing along a previously established field structure, rather than perpendicular to it as in a CME.

Hudson, Hugh; Vilmer, Nicole; Wakeford, Peter

2015-04-01

136

Mixed micelle formation with hydrophobic and hydrophilic Pluronic block copolymers: implications for controlled and targeted drug delivery.  

PubMed

Pluronic block copolymers offer affluent phase behavioral characteristics and are extensively investigated for drug delivery applications. Hydrophobic Pluronics produce larger aggregates whereas hydrophilic Pluronics often generate small-sized micelles in aqueous milieu. To overcome the limitations and combine the advantages of different kinds of Pluronics the mixing of such two types of Pluronics is studied here, especially for hydrophobic Pluronic L81 and relatively hydrophilic Pluronic P123. Critical micelle concentration (CMC) of the developed binary mixtures was 0.032 mg/ml as evidenced from pyrene fluorescence spectroscopy and is located in between that of the individual Pluronics. Dynamic light scattering (DLS) showed very small particle sizes (?20 nm) and low polydispersity indices for most of the mixed micelles. Transmission electron microscopy (TEM) demonstrated spherical shape of micelles. Based upon the ratio of hydrophobic and hydrophilic Pluronics, dispersions of varied stability were obtained. With 0.1/1.0 wt.% and 0.5/3.0 wt.% of Pluronic L81/P123, stable dispersions were obtained. Stability was assessed from turbidity measurement, size analysis and clarity of dispersion on standing. Micelles were also found to be stable in bovine serum albumin (BSA) solution. Mixed micelles showed fairly high entrapment efficiency, loading capacity and sustained release profile for aceclofenac (Acl), a model hydrophobe. Presence of salt lowered Acl solubilization in micelles. Thermodynamic parameters for Acl solubilization in mixed micelles revealed high partition coefficient values and spontaneity of drug solubilization. Thus, the developed novel mixed micelles hold promise in controlled and targeted drug delivery owing to their very small size, high entrapment efficiency and stability. PMID:21862296

Kulthe, S S; Inamdar, N N; Choudhari, Y M; Shirolikar, S M; Borde, L C; Mourya, V K

2011-12-01

137

CME 331.3 (3L-3P alt week) Microprocessor Based Embedded Systems  

E-print Network

CME 331.3 (3L-3P alt week) Microprocessor Based Embedded Systems Department of Electrical.usask.ca/university_secretary/honesty/StudentAcademicAppeals.pdf Course Content: Microprocessor - introductory concepts Intro to Stellaris LaunchPad Microcontroller

Saskatchewan, University of

138

Analysis and Modeling of the UV Spectra of the Feb. 12, 2000 Flux Rope CME.  

NASA Astrophysics Data System (ADS)

UltraViolet spectra of a typical flux rope CME have been taken with the UltraViolet Coronagraph Spectrometer aboard SOHO above the NW limb at heliocentric distance of 2.3 Rsun. The high temporal and spectral resolutions of the spectra provide a detailed monitoring of the dynamical and physical properties of the CME. Beside the cool lines of H I (1216 and 1025 A) and the intermediate lines of O VI (1032, 1037 A) usually observed in CME this event shows emission in the hot lines of SI XII (520 A) and Mg X (610 A). Doppler shift of the observed spectral lines give the line of sight velocity of the bright front and the prominence core plasma. The latter showing evidence for helical motion. A model of the Doppler shift evolution in both front and core of the CME is presented.

Ciaravella, A.; Raymond, J.; van ballegooijen, A.

2001-05-01

139

December 2008 CME as Viewed by Spacecraft - Duration: 0:16.  

NASA Video Gallery

Newly reprocessed images from NASA's STEREO-A spacecraft, allow scientists to trace the anatomy of the December 2008 CME as it moves and changes on its journey from the Sun to the Earth, identify t...

140

SYNTHESIS OF CME-ASSOCIATED MORETON AND EIT WAVE FEATURES FROM MHD SIMULATIONS  

E-print Network

waves are identified. It confirms that the EIT waves, which border the expanding dimmming region that the piston-driven shock straddling over the CME is responsible for both the type II bursts and the Moreton

Chen, P. F.

141

SOHO Captures CME From X5.4 Solar Flare - Duration: 5 seconds.  

NASA Video Gallery

The Solar Heliospheric Observatory (SOHO) captured this movie of the sun's coronal mass ejection (CME) associated with an X5.4 solar flare on the evening of March 6, 2012. The extremely fast and en...

142

Anabolic bone formation via a site-specific bone-targeting delivery system by interfering with semaphorin 4D expression.  

PubMed

Semaphorins have been recently targeted as new molecules directly implicated in the cell-cell communication that occurs between osteoclasts and osteoblasts. Overexpression of certain semaphorins, such as semaphorin4D (sema4D), is found in an osteoporotic phenotype and plays a key role in osteoclast activity by suppressing osteoblast maturation, thus significantly altering the bone modeling cycle. In the present study, we fabricate a site-specific bone-targeting drug-delivery system from polymeric nanoparticles with the incorporation of siRNA interference molecule for sema4D and demonstrate their cellular uptake and intracellular trafficking within osteoclasts, thus preventing the suppression of osteoblast activity. We then demonstrate in an osteoporotic animal model induced by ovariectomy that weekly intravenous injections led to a significantly greater number of active osteoblasts at the bone surface, resulting in higher bone volume in compromised animals. The findings from the present study demonstrate a novel and promising site-specific therapeutic option for the treatment of osteoporosis via interference of the sema4D-plexin cell communication pathway between osteoclasts and osteoblasts. PMID:25088728

Zhang, Yufeng; Wei, Lingfei; Miron, Richard J; Shi, Bin; Bian, Zhuan

2015-02-01

143

The sustained delivery of resveratrol or a defined grape powder inhibits new blood vessel formation in a mouse model of choroidal neovascularization.  

PubMed

The objective of this study was to determine whether resveratrol or a defined, reconstituted grape powder can attenuate the formation of new blood vessels in a mouse model of choroidal neovascularization (CNV). To accomplish this objective, C57BL/6J mice were randomized into control or treatment groups which received either resveratrol or grape powder by daily oral gavage, resveratrol or grape powder delivered ad libitum through the drinking water, or resveratrol by slow release via implanted osmotic pumps. A laser was used to rupture Bruch's membrane to induce CNV which was then detected in sclerochoroidal eyecups stained with antibodies against intercellular adhesion molecule-2. CNV area was measured using fluorescence microscopy and Image J software. Ad libitum delivery of both resveratrol and grape powder was shown to significantly reduce the extent of CNV by 68% and 57%, respectively. Parallel experiments conducted in vitro demonstrated that resveratrol activates p53 and inactivates Akt/protein kinase B in choroidal endothelial cells, contributing to its anti-proliferative and anti-migratory properties. In addition resveratrol was shown to inhibit the formation of endothelial cell networks, augmenting its overall anti-angiogenic effects. The non-toxic nature of resveratrol makes it an especially attractive candidate for the prevention and/or treatment of CNV. PMID:25361423

Kanavi, Mozhgan Rezaie; Darjatmoko, Soesiawati; Wang, Shoujian; Azari, Amir A; Farnoodian, Mitra; Kenealey, Jason D; van Ginkel, Paul R; Albert, Daniel M; Sheibani, Nader; Polans, Arthur S

2014-01-01

144

The Relationship Between Solar X-Ray Flux and Coronal Mass Ejection (CME) Energy  

NASA Astrophysics Data System (ADS)

Solar flares and their associated CMEs are an integral part of solar weather that can have profound effects on Earth's atmosphere. The charged particles emitted by strong CMEs and strong x-ray fluxes produced by solar flares can cause damage to satellites, disrupt radio and GPS signals, and strain power grids. It is critical to understand how solar flare intensity influences the magnitude of CMEs so as to minimize and prevent these consequential negative effects. This study investigated the hypothesis that solar x-ray flux has a direct correlation to CME energy. Total daily x-ray flux was correlated with CME energy for the years 2000-2012. X-ray flux data consisted of background and solar flare flux obtained from the Geostationary Operational Environmental Satellites (GOES). CME energy was obtained by squaring the 2nd-order speed at 20 Rs (solar radii) and summing these squared values for each day of each year. CME speed data was obtained from the NASA Large Angle and Spectrometric Coronagraph (LASCO) located on the Solar and Heliospheric Observatory satellite (SOHO). Results indicate significant correlations between solar x-ray flux and CME energy for the various years. Other factors that influence CME energy were also investigated.

Hirschberger, M.; Damas, M. C.; O'Connell, M.; Mezzafonte, D.; Marchese, A.; Carbone, A.; Chen, K.; Marchese, P.

2013-12-01

145

Web-Based Delivery System for Disaster Prevention Information Using a New Jma Dpi Xml Format and Amedas Data  

NASA Astrophysics Data System (ADS)

The Automated Meteorological Data Acquisition System (AMeDAS) Data is used along with compound disaster information for a geographic information system (GIS) by integration into the Japan Meteorological Agency (JMA) disaster prevention information XML data. A JMA XML format is a next generation format that contains weather warnings, tsunami warnings, and earthquake information, etc. However, it is not possible to process it by reading disaster prevention information XML Data and AMeDAS Data directly to the GIS system. Therefore, development of a program that converts the data structure is important to consolidate a variety of disaster prevention information on the GIS system. Information on escape routes and evacuation sites, etc. were given as points for regional meteorological observation forecasts using AMeDAS Data by disaster prevention information XML data and integrating it where the disaster was generated, giving a range of expansion of damage and a damage level. There are two main aims; the first is to deliver these compound data of disaster prevention information XML data and AMeDAS Data via the Internet. The second aim is to provide GIS files (shapefile format) of these data to such as local governments for their individual analysis. This was furthermore confirmed to enable the construction of a system using WebGIS (Google Maps) and Open Source Software GIS to monitor disaster information at low cost.

Nishio, M.; Mori, M.

2012-07-01

146

Kinematic Treatment of CME Evolution in the Solar Wind  

NASA Technical Reports Server (NTRS)

We present a kinematic study of the evolution of coronal mass ejections (CMEs) in the solar wind. Specifically, we consider the effects of: (1) spherical expansion; and (2) uniform expansion due to pressure gradients between the Interplanetary CME (ICME) and the ambient solar wind. We compare these results with an MHD model, which allows us to isolate these effects from the combined kinematic and dynamical effects, which are included in MHD models. They also provide compelling evidence that the fundamental cross section of so-called "force-free" flux ropes (or magnetic clouds) is neither circular or elliptical, but rather a convex-outward, "pancake" shape. We apply a force-free fitting to the magnetic vectors from the MHD simulation to assess how the distortion of the flux rope affects the fitting. In spite of these limitations, force-free fittings, which are straightforward to apply, do provide an important description of a number of parameters, including the radial dimension, orientation and chirality of the ICME.

Riley, Pete; Crooker, N. U.

2004-01-01

147

CME Eruption Onset Observations from EIT and SXT  

NASA Technical Reports Server (NTRS)

Why CMEs erupt is a major outstanding puzzle of solar physics. Signatures observable at the earliest stages of eruption onset may hold precious clues about the onset mechanism. We present observations in EUV from SOHO/EIT and in soft X-rays from Yohkoh/SXT of the re-eruption and eruption phases of CME expulsion, along with the eruption's magnetic setting found from SOHO/MDI magnetograms. Most of our events involve clearly-observable filament eruptions and multiple neutral lines, and we use the magnetic settings and motions of the filaments to help infer the geometry and behavior of the associated erupting magnetic fields. Pre-eruption and early-eruption signatures include a relatively slow filament rise prior to eruption, and intensity "dimmings" and brightenings, both in the immediate neighborhood of the "core" (location of greatest magnetic shear) of the erupting fields and at locations remote from the core. These signatures and their relative timings place observational constraints on eruption mechanisms; our recent work has focused on implications for the so-called "tether cutting" and "breakout" models, but the same observational constraints are applicable to any model.

Sterling, A. C.

2004-01-01

148

X-ray and EUV Observations of CME Eruption Onset  

NASA Technical Reports Server (NTRS)

Why Coronal Mass Ejections (CMEs) erupt is a major outstanding puzzle of solar physics. Signatures observable at the earliest stages of eruption onset may hold precious clues about the onset mechanism. We present observations from SOHO/EIT and from TRACE in EUV, and from Yohkoh/SXT in soft X-rays of the pre-eruption and eruption phases of CME expulsion, along with the eruption's magnetic setting found from SOHO/MDI magnetograms. Most of our events involve clearly-observable filament eruptions and multiple neutral lines, and we use the magnetic settings and motions of the filaments to help infer the geometry and behavior of the associated erupting magnetic fields. Pre-eruption and early-eruption signatures include a relatively slow filament rise prior to eruption, and intensity "dimmings" and brightenings, both in the immediate neighborhood of the "core" (location of greatest magnetic shear) of the erupting fields and at locations remote from the core. These signatures and their relative timings place observational constraints on eruption mechanisms; our recent work has focused on implications for the so-called "tether cutting" and "breakout" models, but the same observational constraints are applicable to any model.

Sterling, A. C.

2004-01-01

149

Intelligent Multimedia Delivery? It’s a question of semantics  

Microsoft Academic Search

Intelligent multimedia delivery uses semantic information about content to enhance the delivery process. This paper proposes a model for intelligent multimedia delivery that advances the state of the art by incorporating a concept of semantic distortion into the delivery optimization process. Furthermore, the model combines format-independence with rate-distortion optimization to provide a flexible framework for intelligent delivery of multimedia in

Joseph Thomas-Kerr; Ian Burnett; Christian Ritz

2007-01-01

150

Compressed antisolvent precipitation and photopolymerization for the formation of crosslinked polymer microparticles useful for controlled drug delivery  

NASA Astrophysics Data System (ADS)

This work presents novel antisolvent processing technique entitled Compressed Antisolvent Precipitation and Photopolymerization (CAPP) useful for forming crosslinked polymer microparticles. In this process, an organic solvent dissolves monomer and polymerization photoinitiators to form a homogeneous solution. Photopolymerization and microparticle formation occur when the homogeneous solution is sprayed into a compressed antisolvent while being simultaneously exposed to initiating light. We investigated the method of particle formation in the CAPP process to explain the repeatable bimodal particle size distribution obtained under a variety of operating conditions. Ternary phase diagrams of antisolvent, monomer, and solvent solutions were constructed and specific spray paths from the resulting ternary phase diagrams were investigated and the significance of crossing the binodal, as well as the importance of where the binodal was crossed, was discovered. In addition, manipulation of injection conditions, varying process residence times, and nucleation rate calculations were explored to further investigate the means of particle formation. We demonstrate the feasibility of encapsulating therapeutic agents into highly crosslinked polymer particles using the CAPP process. Ion-paired tacrine, erythromycin, erythromycin estolate, and erythromycin ethyl succinate were CAPP processed with poly(ethylene glycol) diacrylate monomers of several molecular weights so that the resulting particles would entrap different sized drugs in networks with varying mesh sizes. In vitro drug release profiles were obtained for all of the various drug-monomer combinations. Diffusion coefficients were estimated by fitting a short time approximation of Fickian release from a sphere of fixed diameter to the release data and were applied to a model of Fickian release from polydisperse spheres, and the results were compared to the in vitro release data. CAPP particle processing was explored in acetone, ethanol, and methanol with respect to reaction kinetics, particle size and morphology, particle double bond conversion, and in vitro drug release. A multifunctional anhydride monomer was also applied to the CAPP process and ion-paired tacrine was successfully encapsulated in the resulting surface eroding, crosslinked polymer microparticles. Degradation of and release from thin disks of photopolymerized monomer, poly(sebacic anhydride dimethacrylate), gave a kinetic constant for surface erosion, which was applied to predict the release of ion-paired tacrine from the CAPP-processed, degradable particles.

Owens, Jennifer Lani

151

Diversity of planetary systems in low-mass disks. Terrestrial-type planet formation and water delivery  

NASA Astrophysics Data System (ADS)

Context. Several studies, observational and theoretical, suggest that planetary systems with only rocky planets are the most common in the Universe. Aims: We study the diversity of planetary systems that might form around Sun-like stars in low-mass disks without gas-giant planets. We focus especially on the formation process of terrestrial planets in the habitable zone (HZ) and analyze their water contents with the goal to determine systems of astrobiological interest. In addition, we study the formation of planets on wide orbits because they can be detected with the microlensing technique. Methods: N-body simulations of high resolution were developed for a wide range of surface density profiles. A bimodal distribution of planetesimals and planetary embryos with different physical and orbital configurations was used to simulate the planetary accretion process. The surface density profile combines a power law for the inside of the disk of the form r-?, with an exponential decay to the outside. We performed simulations adopting a disk of 0.03 M? and values of ? = 0.5, 1 and 1.5. Results: All our simulations form planets in the HZ with different masses and final water contents depending on the three different profiles. For ? = 0.5, our simulations produce three planets in the HZ with masses ranging from 0.03 M? to 0.1 M? and water contents between 0.2 and 16 Earth oceans (1 Earth ocean =2.8 × 10-4 M?). For ? = 1, three planets form in the HZ with masses between 0.18 M? and 0.52 M? and water contents from 34 to 167 Earth oceans. Finally, for ? = 1.5, we find four planets in the HZ with masses ranging from 0.66 M? to 2.21 M? and water contents between 192 and 2326 Earth oceans. This profile shows distinctive results because it is the only one of those studied here that leads to the formation of water worlds. Conclusions: Since planetary systems with ? = 1 and 1.5 present planets in the HZ with suitable masses to retain a long-lived atmosphere and to maintain plate tectonics, they seem to be the most promising candidates to be potentially habitable. Particularly, these systems form Earths and Super-Earths of at least 3 M? around the snow line, which can be discovered by the microlensing technique.

Ronco, M. P.; de Elía, G. C.

2014-07-01

152

Efficacy of an integrated continuing medical education (CME) and quality improvement (QI) program on radiation oncologist (RO) clinical practice  

Microsoft Academic Search

Purpose: There has been little radiation oncologist (RO)-specific research in continuing medical education (CME) or quality improvement (QI) program efficacy. Our aim was to evaluate a CME\\/QI program for changes in RO behavior, performance, and adherence to department protocols\\/studies over the first 12 months of the program. Methods and Materials: The CME\\/QI program combined chart audit with feedback (C-AWF), simulation

Cheng Nang. Leong; Thomas Philip Shakespeare; Rahul K. Mukherjee; Michael F. Back; Khai Mun Lee; Jiade Jay Lu; Christopher J. Wynne; Keith Lim; Johann Tang; Xiaojian Zhang

2006-01-01

153

Solar Mass Ejection Imager (SMEI) Solar Wind 3-D Analysis of the January 20, 2005 CME  

NASA Astrophysics Data System (ADS)

The Solar Mass Ejection Imager (SMEI) has observed the inner heliospheric response in white light from over 200 CMEs. One of these, on January 20, 2005, produced one of the largest Solar Energetic Particle events ever recorded. We show SMEI orbital difference images and the 3D solar wind reconstruction of this well-observed CME, and demonstrate how we can track its outward motion from approximately 20 deg. from the Sun until it vanishes in the SMEI field of view in the direction of the Ulysses spacecraft. Our 3D reconstruction technique is used to obtain perspective views from outward-flowing solar wind as observed from Earth by iteratively fitting a kinematic solar wind density model using the SMEI white light observations. This 3D modeling technique permits us to separate the heliospheric response in SMEI from background noise, and to estimate the 3D structure and transient heliospheric components of the CME and its speed and mass. We then determine the total energy of the CME that can be used as input to determine the total energy output of the event. More information about the spatial extent and energetics of this CME event can be determined by measurements in-situ from the Ulysses spacecraft that was beyond 5 AU and about 35 degrees west of Earth. Ulysses first detected an extremely fast CME response at the spacecraft 7 days following the event on the Sun and the transient flow continued for several days. The SMEI 3D reconstruction shows the event as it passes Earth to the west and helps to disentangle the CME structure. This will allow a better understanding of which portions of the CME intersect Ulysses, and the 3D trajectories of several CMEs observed earlier in coronagraph and SMEI data.

Jackson, B. V.; Buffington, A.; Hick, P. P.; Yu, Y.; Webb, D.

2005-12-01

154

The first observation of a simultaneously bubble-like CME and a jet-like CME produced by a coronal blowout jet  

NASA Astrophysics Data System (ADS)

The coronal blowout jet is a peculiar category among various jet phenomena, of which the sheared base arch, often carrying a small filament, experiences a miniature version of blowout eruption that produces large-scale coronal mass ejection (CME). Here, we report such a coronal blowout jet with high-resolution multi-wavelength and multi-angle observations taken from Solar Dynamics Observatory, Solar Terrestrial Relations Observatory, and Big Bear Solar Observatory. For the first time, we find that a simultaneous bubble-like and a jet-like CMEs were dynamically related to the blowout jet that showed cool and hot components next to each other. Our observational results indicate that: (1) the cool component was resulted from the eruption of the filament contained within the jet's base arch, and it further caused the bubble-like CME; (2) the jet-like CME was associated with the hot component, which was the outward moving heated plasmas generated by the reconnection of the base arch and its ambient open field lines. On the other hand, bifurcation of the jet's cool component was also observed, which was resulted from the uncoupling of the erupting filament's two legs that were highly twisted at the very beginning. Based on these results, we propose a model to interpret the coronal blowout jet, of which the external reconnection not only produces the jet-like CME but also leads to the rising of the filament. Subsequently, internal reconnection starts underneath the rising filament and thereby causes the bubble-like CME.

Shen, Yuandeng

2012-07-01

155

The Formation of Jupiter, the Jovian Early Bombardment and the Delivery of Water to the Asteroid Belt: The Case of (4) Vesta  

PubMed Central

The asteroid (4) Vesta, parent body of the Howardite-Eucrite-Diogenite meteorites, is one of the first bodies that formed, mostly from volatile-depleted material, in the Solar System. The Dawn mission recently provided evidence that hydrated material was delivered to Vesta, possibly in a continuous way, over the last 4 Ga, while the study of the eucritic meteorites revealed a few samples that crystallized in presence of water and volatile elements. The formation of Jupiter and probably its migration occurred in the period when eucrites crystallized, and triggered a phase of bombardment that caused icy planetesimals to cross the asteroid belt. In this work, we study the flux of icy planetesimals on Vesta during the Jovian Early Bombardment and, using hydrodynamic simulations, the outcome of their collisions with the asteroid. We explore how the migration of the giant planet would affect the delivery of water and volatile materials to the asteroid and we discuss our results in the context of the geophysical and collisional evolution of Vesta. In particular, we argue that the observational data are best reproduced if the bulk of the impactors was represented by 1–2 km wide planetesimals and if Jupiter underwent a limited (a fraction of au) displacement. PMID:25370027

Turrini, Diego; Svetsov, Vladimir

2014-01-01

156

The formation of jupiter, the jovian early bombardment and the delivery of water to the asteroid belt: the case of (4) vesta.  

PubMed

The asteroid (4) Vesta, parent body of the Howardite-Eucrite-Diogenite meteorites, is one of the first bodies that formed, mostly from volatile-depleted material, in the Solar System. The Dawn mission recently provided evidence that hydrated material was delivered to Vesta, possibly in a continuous way, over the last 4 Ga, while the study of the eucritic meteorites revealed a few samples that crystallized in presence of water and volatile elements. The formation of Jupiter and probably its migration occurred in the period when eucrites crystallized, and triggered a phase of bombardment that caused icy planetesimals to cross the asteroid belt. In this work, we study the flux of icy planetesimals on Vesta during the Jovian Early Bombardment and, using hydrodynamic simulations, the outcome of their collisions with the asteroid. We explore how the migration of the giant planet would affect the delivery of water and volatile materials to the asteroid and we discuss our results in the context of the geophysical and collisional evolution of Vesta. In particular, we argue that the observational data are best reproduced if the bulk of the impactors was represented by 1-2 km wide planetesimals and if Jupiter underwent a limited (a fraction of au) displacement. PMID:25370027

Turrini, Diego; Svetsov, Vladimir

2014-01-01

157

The CORIMP CME Catalogue: Automatically Detecting and Tracking CMEs in Coronagraph Data  

NASA Astrophysics Data System (ADS)

Studying CMEs in coronagraph data can be challenging due to their diffuse structure and transient nature, and user-specific biases may be introduced through visual inspection of the images. The large amount of data available from the SOHO and STEREO missions also makes manual cataloguing of CMEs tedious, and so a robust method of detection and analysis is required. This has led to the development of automated CME detection and cataloguing packages such as CACTus, SEEDS and ARTEMIS. Here we present the development of the CORIMP (coronal image processing) Catalogue: a new, automated, multiscale, CME detection and tracking catalogue, that overcomes many of the drawbacks of current catalogues. It works by first employing a dynamic CME separation technique to remove the static background, and then characterizing CME structure via a multiscale edge-detection algorithm. The detections are chained through time to determine the CME kinematics and morphological changes as it propagates across the plane-of-sky. The effectiveness of the method is demonstrated by its application to a selection of SOHO/LASCO and STEREO/SECCHI images, as well as to synthetic coronagraph images created from a model corona with a variety of CMEs. These algorithms are being applied to the whole LASCO and SECCHI datasets, and a CORIMP catalogue of results will soon be available to the community.

Byrne, Jason; Morgan, H.; Habbal, S. R.

2012-05-01

158

Stereoscopic Analysis of STEREO/SECCHI Data for CME Trajectory Determination  

NASA Technical Reports Server (NTRS)

The Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) coronagraphs on the twin Solar TErrestrial RElations Observatory (STEREO) spacecraft provide simultaneous views of the corona and coronal mass ejections from two view points. Here, we analyze simultaneous image pairs using the technique of tie-pointing and triangulation (T&T) to determine the three-dimensional trajectory of seven coronal mass ejections (CMEs). The bright leading edge of a CME seen in coronagraph images results from line-of-sight integration through the CME front; the two STEREO coronagraphs see different apparent leading edges, leading to a systematic error in its three-dimensional reconstruction. We analyze this systematic error using a simple geometric model of a CME front. We validate the technique and analysis by comparing T&T trajectory determinations for seven CMEs with trajectories determined by Thernisien et al. (2009) using a forward modeling technique not susceptible to this systematic effect.

Liewer, P. C.; Hall, J. R.; Howard, R. A.; DeJong, E. M.; Thompson, W. T.; Thernisten, A.

2010-01-01

159

Crystal structure of the Campylobacter jejuni CmeC outer membrane channel.  

PubMed

As one of the world's most prevalent enteric pathogens, Campylobacter jejuni is a major causative agent of human enterocolitis and is responsible for more than 400 million cases of diarrhea each year. The impact of this pathogen on children is of particular significance. Campylobacter has developed resistance to many antimicrobial agents via multidrug efflux machinery. The CmeABC tripartite multidrug efflux pump, belonging to the resistance-nodulation-cell division (RND) superfamily, plays a major role in drug resistant phenotypes of C. jejuni. This efflux complex spans the entire cell envelop of C. jejuni and mediates resistance to various antibiotics and toxic compounds. We here report the crystal structure of C. jejuni CmeC, the outer membrane component of the CmeABC tripartite multidrug efflux system. The structure reveals a possible mechanism for substrate export. PMID:24753291

Su, Chih-Chia; Radhakrishnan, Abhijith; Kumar, Nitin; Long, Feng; Bolla, Jani Reddy; Lei, Hsiang-Ting; Delmar, Jared A; Do, Sylvia V; Chou, Tsung-Han; Rajashankar, Kanagalaghatta R; Zhang, Qijing; Yu, Edward W

2014-07-01

160

Coronal Mass Ejection of 26 February 2000: Complete analysis of the three-part CME structure  

NASA Astrophysics Data System (ADS)

We analyze the kinematics and morphology of the limb coronal mass ejection (CME) of 26 February 2000, utilizing observations from Mauna Loa Solar Observatory (MLSO), the Solar and Heliospheric Observatory (SOHO) and the Geostationary Operational Environmental Satellite (GOES). Also, we analyze the relation between dynamics of the CME and the energy release in the associated flare. An intricate structure (prominence, prominence-like absorbing feature, cavity and bright overlying arcade) is clearly recognizable in the low corona during the pre-eruption phase of slow rise. This provided measurements of kinematics of verious features from the very beginning of the eruption up to the post-acceleration phase which was followed up to 32 solar radii. Such events are observed only occasionaly, and are of great importance for the comprehension of the nature of forces driving CMEs. The acceleration maximum was attained at the radial distance of 2.4 solar radii from the solar center and ceased beyond 12 solar radii. The time profiles of the acceleration of various features of CME are showing "self-similar" expansion and implying a common driver. The acceleration phase was synchronized to a certain degree with the impulsive phase of the associated two-ribbon flare. Observations provide clear evidence that CME eruption caused a global restructuring of the magnetic field in the outer and inner corona. Furthermore, kinematics and morphological properties of this CME show possibility that in some events the prominence can evolve into a structure which looks like three-part structure CME, i.e. where the frontal rim is just a part of helically twisted prominence.

Mari?i?, D.; Vršnak, B.; Roša, D.; Hržina, D.

2012-11-01

161

The Solar Stormwatch CME catalogue: Results from the first space weather citizen science project  

NASA Astrophysics Data System (ADS)

Solar Stormwatch was the first space weather citizen science project, the aim of which is to identify and track coronal mass ejections (CMEs) observed by the Heliospheric Imagers aboard the STEREO satellites. The project has now been running for approximately 4 years, with input from >16,000 citizen scientists, resulting in a data set of >38,000time-elongation profiles of CME trajectories, observed over 18 preselected position angles. We present our method for reducing this data set into a CME catalogue. The resulting catalogue consists of 144 CMEs over the period January 2007 to February 2010, of which 110 were observed by STEREO-A and 77 were observed by STEREO-B. For each CME, the time-elongation profiles generated by the citizen scientists are averaged into a consensus profile along each position angle that the event was tracked. We consider this catalogue to be unique, being at present the only citizen science-generated CME catalogue, tracking CMEs over an elongation range of 4° out to a maximum of approximately 70°. Using single spacecraft fitting techniques, we estimate the speed, direction, solar source region, and latitudinal width of each CME. This shows that at present, the Solar Stormwatch catalogue (which covers only solar minimum years) contains almost exclusively slow CMEs, with a mean speed of approximately 350 km s-1. The full catalogue is available for public access at www.met.reading.ac.uk/~spate/solarstormwatch. This includes, for each event, the unprocessed time-elongation profiles generated by Solar Stormwatch, the consensus time-elongation profiles, and a set of summary plots, as well as the estimated CME properties.

Barnard, L.; Scott, C.; Owens, M.; Lockwood, M.; Tucker-Hood, K.; Thomas, S.; Crothers, S.; Davies, J. A.; Harrison, R.; Lintott, C.; Simpson, R.; O'Donnell, J.; Smith, A. M.; Waterson, N.; Bamford, S.; Romeo, F.; Kukula, M.; Owens, B.; Savani, N.; Wilkinson, J.; Baeten, E.; Poeffel, L.; Harder, B.

2014-12-01

162

Delivery methods for LVSD systems  

NASA Astrophysics Data System (ADS)

In this paper we present formats and delivery methods of Large Volume Streaming Data (LVSD) systems. LVSD systems collect TBs of data per mission with aggregate camera sizes in the 100 Mpixel to several Gpixel range at temporal rates of 2 - 60 Hz. We present options and recommendations for the different stages of LVSD data collection and delivery, to include the raw (multi-camera) data, delivery of processed (stabilized mosaic) data, and delivery of user-defined region of interest windows. Many LVSD systems use JPEG 2000 for the compression of raw and processed data. We explore the use of the JPEG 2000 Interactive Protocol (JPIP) for interactive client/server delivery to thick-clients (desktops and laptops) and MPEG-2 and H.264 to handheld thin-clients (tablets, cell phones). We also explore the use of 3D JPEG 2000 compression, defined in ISO 15444-2, for storage and delivery as well. The delivery of raw, processed, and region of interest data requires different metadata delivery techniques and metadata content. Beyond the format and delivery of data and metadata we discuss the requirements for a client/server protocol that provides data discovery and retrieval. Finally, we look into the future as LVSD systems perform automated processing to produce "information" from the original data. This information may include tracks of moving targets, changes of the background, snap shots of targets, fusion of multiple sensors, and information about "events" that have happened.

Kasner, James H.; Brower, Bernard V.

2011-06-01

163

Role of Ambient Solar Wind Conditions in CME evolution (P21)  

NASA Astrophysics Data System (ADS)

ipsraj@yahoo.com Solar events are mainly responsible for producing storms at the Earth. Coronal Mass Ejection (CME) is a major cause for this. In this paper, Coronal Mass Ejections occurred during 1998-2004 are studied. Ambient solar wind does play some role in determining the effect of a CME. The effects produced at the Earth during the period 1999 2004 are considered and an attempt has been made to understand the role of ambient solar wind. This is to draw some conclusion about how some of the events become geo- effective.

Jadav, R.; Jadeja, A. K.; Iyer, K. N.

2006-11-01

164

Analysis and study of the in situ observation of the June 1st 2008 CME by STEREO  

Microsoft Academic Search

In this work we present a combined study of the counterpart of the coronal mass ejection (CME) of June 1st of 2008 in the interplanetary medium. This event has been largely studied because of its peculiar initiation and its possible forecasting consequences for space weather. We show an in situ analysis (on days June 6th–7th of 2008) of the CME

T. Nieves-Chinchilla; R. Gómez-Herrero; A. F. Viñas; O. Malandraki; N. Dresing; M. A. Hidalgo; A. Opitz; J.-A. Sauvaud; B. Lavraud; J. M. Davila

2011-01-01

165

INVESTIGATION OF THE FORMATION AND SEPARATION OF AN EXTREME-ULTRAVIOLET WAVE FROM THE EXPANSION OF A CORONAL MASS EJECTION  

SciTech Connect

We address the nature of EUV waves through direct observations of the formation of a diffuse wave driven by the expansion of a coronal mass ejection (CME) and its subsequent separation from the CME front. The wave and the CME on 2011 June 7 were well observed by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. Following the solar eruption onset, marked by the beginning of the rapid increasing of the CME velocity and the X-ray flux of accompanying flare, the CME exhibits a strong lateral expansion. During this impulsive expansion phase, the expansion speed of the CME bubble increases from 100 km s{sup -1} to 450 km s{sup -1} in only six minutes. An important finding is that a diffuse wave front starts to separate from the front of the expanding bubble shortly after the lateral expansion slows down. Also a type II burst is formed near the time of the separation. After the separation, two distinct fronts propagate with different kinematic properties. The diffuse front travels across the entire solar disk, while the sharp front rises up, forming the CME ejecta with the diffuse front ahead of it. These observations suggest that the previously termed EUV wave is a composite phenomenon and driven by the CME expansion. While the CME expansion is accelerating, the wave front is cospatial with the CME front, thus the two fronts are indiscernible. Following the end of the acceleration phase, the wave moves away from the CME front with a gradually increasing distance between them.

Cheng, X.; Ding, M. D. [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Zhang, J. [School of Physics, Astronomy and Computational Sciences, George Mason University, Fairfax, VA 22030 (United States); Olmedo, O. [NRC, Naval Research Laboratory, Washington, DC 20375 (United States); Vourlidas, A. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Liu, Y., E-mail: dmd@nju.edu.cn, E-mail: jzhang7@gmu.edu [Space Science Laboratory, University of California, Berkeley, CA 94720 (United States)

2012-01-20

166

Effects of efflux-pump inducers and genetic variation of the multidrug transporter cmeB in biocide resistance of Campylobacter jejuni and Campylobacter coli.  

PubMed

Multidrug efflux pumps, such as CmeABC and CmeDEF, are involved in the resistance of Campylobacter to a broad spectrum of antimicrobials. The aim of this study was to analyse the effects of two putative efflux-pump inducers, bile salts and sodium deoxycholate, on the resistance of Campylobacter to biocides (triclosan, benzalkonium chloride, chlorhexidine diacetate, cetylpyridinium chloride and trisodium phosphate), SDS and erythromycin. The involvement of the CmeABC and CmeDEF efflux pumps in this resistance was studied on the basis of the effects of bile salts and sodium deoxycholate in Campylobacter cmeB, cmeF and cmeR mutants. The genetic variation in the cmeB gene was also examined, to see whether this polymorphism is related to the function of the efflux pump. In 15 Campylobacter jejuni and 23 Campylobacter coli strains, bile salts and sodium deoxycholate increased the MICs of benzalkonium chloride, chlorhexidine diacetate, cetylpyridinium chloride and SDS, and decreased the MICs of triclosan, trisodium phosphate and erythromycin. Bile salts and sodium deoxycholate further decreased or increased the MICs of biocides and erythromycin in the cmeF and cmeR mutants. For cmeB polymorphisms, 17 different cmeB-specific PCR-RFLP patterns were identified: six within C. jejuni only, nine within C. coli only and two in both species. In conclusion, bile salts and sodium deoxycholate can increase or decrease bacterial resistance to structurally unrelated antimicrobials. The MIC increases in the cmeF and cmeR mutants indicated that at least one non-CmeABC efflux system is involved in resistance to biocides. These results indicate that the cmeB gene polymorphism identified is not associated with biocide and erythromycin resistance in Campylobacter. PMID:23161768

Mavri, Ana; Smole Možina, Sonja

2013-03-01

167

Reconciling CME Kinematics using Radio and White-light Observations from STEREO and SOHO  

NASA Astrophysics Data System (ADS)

We study the characteristics of nonthermal radio emission associated with coronal mass ejections (CMEs) observed by STEREO, SOHO, and Wind spacecraft. In particular, we examine three backside CMEs associated with type II radio bursts at frequencies below 16 MHz. These bursts are known to be excellent indicators of solar energetic particle events. We use the universal drift rate spectrum of type II radio bursts and the inferred density scale heights in the corona and interplanetary medium o estimate the speed of the shock waves that produce the type II radio bursts. We find that the radio bursts can provide an accurate estimate of the CME speeds. We consider three backside events and a cannibalism event to show the usefulness of radio dynamic spectrum in inferring CME kinematics. We use radio direction finding technique to show that CME-CME interaction results in enhanced nonthermal radio emission. The radio data also provide constraints on the particle acceleration mechanisms and the reason for the energetic particles observed at wide-ranging longitudes. Finally we infer the shape and extent of the shock associated with one of the biggest solar energetic particle events in the space era.

Gopalswamy, Nat; Yashiro, Seiji; Xie, Hong; Makela, Pertti; Akiyama, Sachiko; Reiner, Michael; MacDowall, Robert

2014-05-01

168

Medical Education and Communication Companies Involved in CME: An Updated Profile  

ERIC Educational Resources Information Center

Introduction: Medical Education and Communication Companies (MECCs) represent approximately 21% of the providers accredited by the Accreditation Council for Continuing Medical Education (ACCME), yet relatively little is known about these organizations in the greater continuing medical education (CME) community. Two prior studies described them,…

Peterson, Eric D.; Overstreet, Karen M.; Parochka, Jacqueline N.; Lemon, Michael R.

2008-01-01

169

Relativistic electron losses related to EMIC waves during CIR and CME storms  

E-print Network

­particle interactions with electromagnetic ion-cyclotron (EMIC) waves during corotating interaction region (CIR) stormsRelativistic electron losses related to EMIC waves during CIR and CME storms M.I. Sandanger a,�, F o Article history: Accepted 14 July 2008 Available online 30 July 2008 PACS: 94.30.Lr 94.30.cb 94

Bergen, Universitetet i

170

Interrater Reliability to Assure Valid Content in Peer Review of CME-Accredited Presentations  

ERIC Educational Resources Information Center

Introduction: The Accreditation Council for Continuing Medical Education (ACCME) provides guidelines for continuing medical education (CME) materials to mitigate problems in the independence or validity of content in certified activities; however, the process of peer review of materials appears largely unstudied and the reproducibility of…

Quigg, Mark; Lado, Fred A.

2009-01-01

171

Effects of the June 2011 CME Observed by Mars Express Ionospheric Sounding  

NASA Astrophysics Data System (ADS)

We show the effects of a strong coronal mass ejection on the Martian ionosphere as directly observed by the Active Ionospheric Sounding (AIS) mode of the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) on board the Mars Express spacecraft. We are able to time the onset, peak, and recovery from the CME through in situ background provided by the High-Energy Neutron Detector on board the Mars Odyssey spacecraft and the ASPERA-3 plasma instrument on board Mars Express. Increased electron intensity for the duration of the CME is confirmed by disappearance of the MARSIS AIS surface reflection and disruption of the MARSIS Subsurface mode surface reflection. Local electron density and magnetic field strength measurements from MARSIS AIS show that prior to CME peak intensity, there is compression of the Martian ionosphere accompanied by simultaneous plasma density and magnetic field strength oscillation. At the peak of the CME, the Martian ionosphere is compressed enough to be completely below the orbit of Mars Express. The ionospheric peak, usually detectable by MARSIS AIS remote sounding out to about 100° solar zenith angle, is extended at significant density to solar zenith angles of 113°. The nature of this increase, whether due to increased flow or increased ionization due to particle flux, continues to be a subject of inquiry.

Morgan, D. D.; Gurnett, D. A.; Duru, F.; Dubinin, E.; Fraenz, M.; Opgenoorth, H. J.; Andrews, D. J.; Ulusen, D.; Mitrofanov, I.; Plaut, J. J.

2012-12-01

172

Diagnostic Role of PET in Dementia CME Author: Hossein Jadvar, MD, PhD, MPH  

E-print Network

Diagnostic Role of PET in Dementia CME Author: Hossein Jadvar, MD, PhD, MPH Complete author of dementias such as Alzheimer's disease. Goal The objective of this activity is to spotlight the clinical of dementias such as Alzheimer's disease; to define appropriate settings for the use of this technology

Jadvar, Hossein

173

Are CME 'interactions' Really Important for Accelerating Major Solar Energetic Particle Events?  

NASA Technical Reports Server (NTRS)

Recent studies have proposed that the presence or absence of an interaction with a preceding coronal mass ejection (CME) or other coronal structure within approximately 50R(sub s), of the Sun discriminates large, fast CMEs associated with major solar energetic particle (SEP) events from those that are not. We conclude that there is no compelling evidence that, if such interactions take place, they play an important role in SEP acceleration. Reasons include: The reported statistical results are consistent with a chance association between interacting CMEs and SEP events; Energetic SEPs are detected at Earth typically before or around the time when the primary CME enters the LASCO C2 field of view - interactions higher in the corona cannot play a role in acceleration of these particles; For approximately 60% of major SEP events in 1997-2001, the preceding CME fades into the background corona or is relatively narrow (less than 40 deg), suggesting any interaction will be weak; Radio signatures attributed to CME interaction occur after SEP acceleration has commenced.

Richardson, I. G.; Lawrence, G. R.; Haggerty, D. K.; Kucera, T.; Szabo, A.

2002-01-01

174

Three Dimensional Modeling of a CME event Observed in LASCO and UVCS  

NASA Astrophysics Data System (ADS)

The dynamics of magnetic flux ropes near the sun are studied by solving model equations [1,2] which describe a flux-rope-geometry coronal mass ejection (CME). This model is applied to a 2000 February 11 CME event, which was observed by both the UVCS spectrometer and the LASCO coronagraph. The UVCS spectrometer provides line-of-sight Doppler velocities for the CME plasma, while LASCO images provide position and velocity information for the CME projected onto the plane of the sky. The result is three-dimensional (3D) data that can be compared to 3D model results. However, ambiguities in the model-data correspondence depend both on the assumed density structure within the model flux rope and the interpretation of the data. The data (EIT, MK4, LASCO, UVCS) and corresponding model results will be presented and discussed. [1] Chen, J. 1996, JGR, 101, 27499 [2] Krall, J. et al., 2000, ApJ, 539, 964 Supported by ONR.

Krall, J.; Chen, J.; Howard, R.; Ciaravella, A.

2001-12-01

175

Constraints on CME Evolution from in situ Observations of Ionic Charge States  

NASA Technical Reports Server (NTRS)

We present a novel procedure for deriving the physical properties of Coronal Mass Ejections (CMES) in the corona. Our methodology uses in-situ measurements of ionic charge states of C, O, Si and Fe in the heliosphere and interprets them in the context of a model for the early evolution of ICME plasma, between 2 - 5 R-solar. We find that the data can be fit only by an evolution that consists of an initial heating of the plasma, followed by an expansion that ultimately results in cooling. The heating profile is consistent with a compression of coronal plasma due to flare reconnect ion jets and an expansion cooling due to the ejection, as expected from the standard CME/flare model. The observed frozen-in ionic charge states reflect this time-history and, therefore, provide important constraints for the heating and expansion time-scales, as well as the maximum temperature the CME plasma is heated to during its eruption. Furthermore, our analysis places severe limits on the possible density of CME plasma in the corona. We discuss the implications of our results for CME models and for future analysis of ICME plasma composition.

Gruesbeck, Jacob R.; Lepri, Susan T.; Zurbuchen, Thomas H.; Antiochos, Spiro K.

2010-01-01

176

Organizational Change in Management of Hepatitis C: Evaluation of a CME Program  

ERIC Educational Resources Information Center

Introduction: Effective treatment regimens exist for the hepatitis C virus (HCV); however, clinicians are often resistant to evaluation or treatment of patients with alcohol or substance abuse problems. We describe a continuing medical education (CME) program for clinicians in a nationwide health care system, with emphasis on current treatment…

Garrard, Judith; Choudary, Veena; Groom, Holly; Dieperink, Eric; Willenbring, Mark L.; Durfee, Janet M.; Ho, Samuel B.

2006-01-01

177

After Delivery  

MedlinePLUS

... after delivery. For many, it's a period of odd blood glucose swings. Not being able to predict ... stressed from lack of sleep, and off schedule. Odd sleep patterns increase the danger of napping through ...

178

Prevalence of the Campylobacter multi-drug efflux pump (CmeABC) in Campylobacter spp. Isolated from freshly processed Turkeys.  

PubMed

The prevalence of the Campylobacter multi-drug efflux pump (CmeABC) was evaluated in Campylobacter isolates recovered from freshly processed turkeys at two Midwestern processing plants. A total of 94 Campylobacter isolates recovered from processed turkeys were examined using polymerase chain reaction (PCR) to determine the presence of the multi-drug efflux pump genes cmeA, cmeB, and cmeC. Results from this study found that 51% of all isolates tested were positive for CmeABC. 46.6% of these positive isolates were from plant A and 55.1% from plant B. Differences were observed in the prevalence of individual genes found among Campylobacter isolates from each plant. Additional analysis found that among the isolates positive for CmeABC, 85.5% were identified as C. jejuni and 14.5% identified as C. coli. There was a relatively high occurrence of the Campylobacter multi-drug efflux pump genes in Campylobacter spp. recovered from processed turkeys, however, the presence of the genes could not be significantly linked to antimicrobial resistance observed in the test strains and suggests that the CmeABC genes are only one factor associated with antimicrobial resistance in Campylobacter spp. PMID:16943037

Olah, Pamela A; Doetkott, Curt; Fakhr, Mohamed K; Logue, Catherine M

2006-08-01

179

Formation of a selenium-substituted rhodanese by reaction with selenite and glutathione: Possible role of a protein perselenide in a selenium delivery system  

PubMed Central

Selenophosphate is the active selenium-donor compound required by bacteria and mammals for the specific synthesis of Secys-tRNA, the precursor of selenocysteine in selenoenzymes. Although free selenide can be used in vitro for the synthesis of selenophosphate, the actual physiological selenium substrate has not been identified. Rhodanese (EC 2.3.1.1) normally occurs as a persulfide of a critical cysteine residue and is believed to function as a sulfur-delivery protein. Also, it has been demonstrated that a selenium-substituted rhodanese (E-Se form) can exist in vitro. In this study, we have prepared and characterized an E-Se rhodanese. Persulfide-free bovine-liver rhodanese (E form) did not react with SeO\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\mathrm{_{3}^{2-}}}\\end{equation*}\\end{document} directly, but in the presence of reduced glutathione (GSH) and SeO\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\mathrm{_{3}^{2-}}}\\end{equation*}\\end{document} E-Se rhodanese was generated. These results indicate that the intermediates produced from the reaction of GSH with SeO\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\mathrm{_{3}^{2-}}}\\end{equation*}\\end{document} are required for the formation of a selenium-substituted rhodanese. E-Se rhodanese was stable in the presence of excess GSH at neutral pH at 37°C. E-Se rhodanese could effectively replace the high concentrations of selenide normally used in the selenophosphate synthetase in vitro assay in which the selenium-dependent hydrolysis of ATP is measured. These results show that a selenium-bound rhodanese could be used as the selenium donor in the in vitro selenophosphate synthetase assay. PMID:11493708

Ogasawara, Yuki; Lacourciere, Gerard; Stadtman, Thressa C.

2001-01-01

180

The SCEC Community Modeling Environment(SCEC/CME): A Collaboratory for Seismic Hazard Analysis  

NASA Astrophysics Data System (ADS)

The SCEC Community Modeling Environment (SCEC/CME) Project is an NSF-supported Geosciences/IT partnership that is actively developing an advanced information infrastructure for system-level earthquake science in Southern California. This partnership includes SCEC, USC's Information Sciences Institute (ISI), the San Diego Supercomputer Center (SDSC), the Incorporated Institutions for Research in Seismology (IRIS), and the U.S. Geological Survey. The goal of the SCEC/CME is to develop seismological applications and information technology (IT) infrastructure to support the development of Seismic Hazard Analysis (SHA) programs and other geophysical simulations. The SHA application programs developed on the Project include a Probabilistic Seismic Hazard Analysis system called OpenSHA. OpenSHA computational elements that are currently available include a collection of attenuation relationships, and several Earthquake Rupture Forecasts (ERFs). Geophysicists in the collaboration have also developed Anelastic Wave Models (AWMs) using both finite-difference and finite-element approaches. Earthquake simulations using these codes have been run for a variety of earthquake sources. Rupture Dynamic Model (RDM) codes have also been developed that simulate friction-based fault slip. The SCEC/CME collaboration has also developed IT software and hardware infrastructure to support the development, execution, and analysis of these SHA programs. To support computationally expensive simulations, we have constructed a grid-based scientific workflow system. Using the SCEC grid, project collaborators can submit computations from the SCEC/CME servers to High Performance Computers at USC and TeraGrid High Performance Computing Centers. Data generated and archived by the SCEC/CME is stored in a digital library system, the Storage Resource Broker (SRB). This system provides a robust and secure system for maintaining the association between the data seta and their metadata. To provide an easy-to-use system for constructing SHA computations, a browser-based workflow assembly web portal has been developed. Users can compose complex SHA calculations, specifying SCEC/CME data sets as inputs to calculations, and calling SCEC/CME computational programs to process the data and the output. Knowledge-based software tools have been implemented that utilize ontological descriptions of SHA software and data can validate workflows created with this pathway assembly tool. Data visualization software developed by the collaboration supports analysis and validation of data sets. Several programs have been developed to visualize SCEC/CME data including GMT-based map making software for PSHA codes, 4D wavefield propagation visualization software based on OpenGL, and 3D Geowall-based visualization of earthquakes, faults, and seismic wave propagation. The SCEC/CME Project also helps to sponsor the SCEC UseIT Intern program. The UseIT Intern Program provides research opportunities in both Geosciences and Information Technology to undergraduate students in a variety of fields. The UseIT group has developed a 3D data visualization tool, called SCEC-VDO, as a part of this undergraduate research program.

Maechling, P. J.; Jordan, T. H.; Minster, J. B.; Moore, R.; Kesselman, C.

2005-12-01

181

DFT NORMAL MODES ON TERTIARY CATION EtCMeCHEtO-TMS FOLLOWED BY REOPTIMIZATION USING THE ANALYTIC FORCE  

E-print Network

+ DFT NORMAL MODES ON TERTIARY CATION EtCMeCHEtO-TMS FOLLOWED BY REOPTIMIZATION USING THE ANALYTIC. ********************************************* Gaussian 98: x86-Win32-G98RevA.7 11-Apr-1999 10-Sep-2001 ********************************************* %chk=etcmechetoTMS

Morton, Thomas Hellman

182

An Investigation of the CME of 3 November 2011 and Its Associated Widespread Solar Energetic Particle Event  

NASA Astrophysics Data System (ADS)

Multi-spacecraft observations are used to study the in-situ effects of a large coronal mass ejection (CME) erupting from the farside of the Sun on 3 November 2011, with particular emphasis on the associated solar energetic particle (SEP) event. At that time both Solar Terrestrial Relations Observatory (STEREO) spacecraft were located more than 90 degrees from Earth and could observe the CME eruption directly, with the CME visible on-disk from STEREO-B and off the limb from STEREO-A. Signatures of pressure variations in the corona such as deflected streamers were seen, indicating the presence of a coronal shock associated with this CME eruption. The evolution of the CME and an associated extreme-ultraviolet (EUV) wave were studied using EUV and coronagraph images. It was found that the lateral expansion of the CME low in the corona closely tracked the propagation of the EUV wave, with measured velocities of 240±19 km s-1 and 221±15 km s-1 for the CME and wave, respectively. Solar energetic particles were observed to arrive first at STEREO-A, followed by electrons at the Wind spacecraft at L1, then STEREO-B, and finally protons arrived simultaneously at Wind and STEREO-B. By carrying out a velocity-dispersion analysis on the particles arriving at each location, it was found that energetic particles arriving at STEREO-A were released first and that the release of particles arriving at STEREO-B was delayed by about 50 minutes. Analysis of the expansion of the CME to a wider longitude range indicates that this delay is a result of the time taken for the CME edge to reach the footpoints of the magnetic-field lines connected to STEREO-B. The CME expansion is not seen to reach the magnetic footpoint of Wind at the time of solar-particle release for the particles detected here, suggesting that these particles may not be associated with this CME.

Prise, A. J.; Harra, L. K.; Matthews, S. A.; Long, D. M.; Aylward, A. D.

2014-05-01

183

A pilot study of CME on risk management in long-term care.  

PubMed

This pilot study's purpose was to evaluate behavioral changes among medical directors and physicians following CME on risk management in long-term care (LTC) facilities. The setting was a satellite conference at the AGS Meeting Symposium 2000. CME participants included 51 medical directors, attending physicians, and nurses. Evaluations were based on 20 LTC medical directors and physicians. Descriptive statistics were used for outcome measurements. Respondents (n = 15, 75%) "committed" to an average of 3 changes. Of the 45 commitments, no progress was reported on 8 (17.7%); another 8 commitments were reported as fully completed. The mean implementation rate was 60%. LTC physicians departed the course with intentions to alter their behaviors, but important obstacles such as "lack of time" and "staff not available or interested" interfered with implementation. PMID:15778147

Powers, James; Pichert, James W; Habermann, Ralf; Ribble, Rachel

2004-01-01

184

Coordinated UVCS/LASCO/EIT Observations of a High Latitude CME  

NASA Astrophysics Data System (ADS)

We present here the results of our coordinated UVCS/LASCO/EIT observations of a CME on 2000 March 5. The northern polar region of the Sun at a position angle 270 degrees was monitored with UVCS at 2 solar radii for about 8 hours. During that time interval a spectacular CME developed in the northern hemisphere. This event was also detected and monitored with LASCO C2 and C3 and the EIT for several hours. We compare the edge-enhanced LASCO and EIT images of this event with the increased intensities of the H I Lyman-alpha spectral line and the line pair O VI 1031.91 A and 1037.61 A seen in the UVCS observations. LASCO and EIT images are essential in providing the larger scale context for this event and for correlating the small-scale sub-structure observed in white light with the the plasma morphology as observed with the UVCS.

Karovska, M.; Esser, R.; Dobrzycka, D.; Kohl, J.

2001-05-01

185

Modeling CME-shock-driven storms in 2012-2013: MHD test particle simulations  

NASA Astrophysics Data System (ADS)

The Van Allen Probes spacecraft have provided detailed observations of the energetic particles and fields environment for coronal mass ejection (CME)-shock-driven storms in 2012 to 2013 which have now been modeled with MHD test particle simulations. The Van Allen Probes orbital plane longitude moved from the dawn sector in 2012 to near midnight and prenoon for equinoctial storms of 2013, providing particularly good measurements of the inductive electric field response to magnetopause compression for the 8 October 2013 CME-shock-driven storm. An abrupt decrease in the outer boundary of outer zone electrons coincided with inward motion of the magnetopause for both 17 March and 8 October 2013 storms, as was the case for storms shortly after launch. Modeling magnetopause dropout events in 2013 with electric field diagnostics that were not available for storms immediately following launch have improved our understanding of the complex role that ULF waves play in radial transport during such events.

Hudson, M. K.; Paral, J.; Kress, B. T.; Wiltberger, M.; Baker, D. N.; Foster, J. C.; Turner, D. L.; Wygant, J. R.

2015-02-01

186

Magnetic Interaction of a Super-CME with the Earth's Magnetosphere: Scenario for Young Earth  

E-print Network

Solar eruptions, known as Coronal Mass Ejections (CMEs), are frequently observed on our Sun. Recent Kepler observations of superflares on G-type stars have implied that so called super-CMEs, possessing kinetic energies 10 times of the most powerful CME event ever observed on the Sun, could be produced with a frequency of 1 event per 800-2000 yr on solar-like slowly rotating stars. We have performed a 3D time-dependent global magnetohydrodynamic simulation of the magnetic interaction of such a CME cloud with the Earth's magnetosphere. We calculated the global structure of the perturbed magnetosphere and derive the latitude of the open-closed magnetic field boundary. We also estimated energy fluxes penetrating the Earth's ionosphere and discuss the consequences of energetic particle fluxes on biological systems on early Earth.

Airapetian, Vladimir S; Danchi, William

2014-01-01

187

UVCS\\/SOHO observations of a CME-driven shock: Consequences on ion heating mechanisms behind a coronal shock  

Microsoft Academic Search

We report the observation of a 1100 km s-1 CME-driven shock with the UltraViolet Coronagraph Spectrometer (UVCS) telescope operating on board SOHO on March 3, 2000. The shock speed was derived from the type II radio burst drift rate and from UVCS observations that can yield the density profile just before the passage of the shock. A CME projected speed

S. Mancuso; J. C. Raymond; J. Kohl; Y.-K. Ko; M. Uzzo; R. Wu

2002-01-01

188

The Double-belt Outer Radiation Belt During CME- and CIR-driven Geomagnetic Storms  

NASA Astrophysics Data System (ADS)

We have identified 8 events with double-belt structure in the outer radiation belt from 110 CME-driven magnetic storms and 223 CIR-driven storms during 1994 to 2003 based on the SAMPEX data sets. Among them, 3 cases are related to CME-driven magnetic storms and 5 cases are related CIR-driven storms. All double-belt structure events in the outer radiation belt are found during the recovery phase of a magnetic storm for both CME- and CIR-related events---they usually start to form within 3-4 days after the onset of the magnetic storm. The pre-conditions needed to form a double-belt structure, for all the CME-related events, are found to be high solar wind dynamic pressure (Pdy) and southward IMF Bz; Nevertheless, for the CIR-related events, they are found to be associated with high speed stream with southward interplanetary magnetic field caused by the Russell-McPherron effect. It is further found that the double-belt structure can be fitted well with a simple exponential decay function. Based on the RBC index, the proportion of the total number of 1.5-6.0MeV electrons inside the position of maximum fluxes to that outside the maximum fluxes keeps rising during the double-belt period, which implies that the acceleration mainly occurs at regions inside the location of maximum fluxes. We suggest that local acceleration mechanisms play an important role in the development of the higher belt during the period of the double-belt structure event in the outer radiation belt.

Yuan, C.; Zong, Q.

2013-12-01

189

Relationship between CME Parameters and Large-Scale Structure of Solar Magnetic Fields  

NASA Astrophysics Data System (ADS)

In this work, we explore how the parameters of coronal mass ejections (CME) associated with eruptive prominences (EP) depend on their position relative to the coronal streamer belt (CSB) and coronal streamer chains (CSCs). We show that the CMEs whose axes are close to CSB propagate at lower mean speed than the CMEs observed in the vicinity of CSCs. The CMEs concentrated at CSCs have larger mean kinetic energy than those associated with CSB. The mean mass is maximum for the events associated with CSB and minimum for events observed near the base of open magnetic field configurations (OMF) - counterparts of coronal holes. The mean angular size is virtually the same for the CMEs of both types. The CME deviation from the radial trajectory has been studied. It is shown that CMEs may deviate noticeably from the radial propagation both on their way from the origin site (prominence eruption site) up to about 2.5 solar radii (Ro) and farther, from ~2.5 up to 20 Ro. In the epoch of solar minimum and at the rise of the cycle, the deviation in the first part of the trajectory (up to 2.5 Ro) is mainly towards the equator. In the other phases, no preferable direction has been revealed. As the EP latitude increases up to ±45°, the CME deviation, on the average, increases, too. It is shown that about 50% of all CMEs change the sense of deviation when passing from the near-solar part of the trajectory to its far part so that, as the CME moves away from the Sun, its propagation becomes more radial. The results obtained show that large-scale solar magnetic fields have a significant effect on the characteristics and propagation of coronal mass ejections.

Fainshtein, V. G.; Ivanov, E. V.

2010-11-01

190

The Dependence of Characteristic Times of Gradual SEP Events on Their Associated CME Properties  

NASA Astrophysics Data System (ADS)

It is generally believed that coronal mass ejections CMEs are the drivers of shocks that accelerate gradual solar energetic particles SEPs One might expect that the characteristics of the SEP intensity time profiles observed at 1 AU are determined by properties of the associated CMEs such as the radial speed and the angular width Recently Kahler statistically investigated the characteristic times of gradual SEP events observed from 1998-2002 and their associated coronal mass ejection properties Astrophys J 628 1014--1022 2005 Three characteristic times of gradual SEP events are determined as functions of solar source longitude 1 T 0 the time from associated CME launch to SEP onset at 1 AU 2 T R the rise time from SEP onset to the time when the SEP intensity is a factor of 2 below peak intensity and 3 T D the duration over which the SEP intensity is within a factor of 2 of the peak intensity However in his study the CME speeds and angular widths are directly taken from the LASCO CME catalog In this study we analyze the radial speeds and the angular widths of CMEs by an ice-cream cone model and re-investigate their correlationships with the characteristic times of the corresponding SEP events We find T R and T D are significantly correlated with radial speed for SEP events in the best-connected longitude range and there is no correlation between T 0 and CME radial speed and angular width which is consistent with Kahler s results On the other hand it s found that T R and T D are also have

Pan, Z. H.; Wang, C. B.; Xue, X. H.; Wang, Y. M.

191

Relativistic electron losses related to EMIC waves during CIR and CME storms  

E-print Network

of radiation belt electrons to the atmosphere due to wave­particle interactions with electromagnetic ionRelativistic electron losses related to EMIC waves during CIR and CME storms M.I. Sandanger a,�, F o Article history: Accepted 14 July 2008 PACS: 94.30.Lr 94.30.cb 94.30.Xy 94.30.cv 94.20.wj 94.30.Ny

Bergen, Universitetet i

192

THE 'TWIN-CME' SCENARIO AND LARGE SOLAR ENERGETIC PARTICLE EVENTS IN SOLAR CYCLE 23  

SciTech Connect

Energetic particles in large solar energetic particle (SEP) events are a major concern for space weather. Recently, Li et al. proposed a 'twin-CME' scenario for ground-level events. Here we extend that study to large SEP events in solar cycle 23. Depending on whether preceding coronal mass ejections (CMEs) within 9 hr exist and whether ions >10 MeV nucleon{sup -1} exceed 10 pfu, we categorize fast CMEs with speed >900 km s{sup -1} and width >60 Degree-Sign from the western hemisphere source regions into four groups: groups I and II are 'twin' and single CMEs that lead to large SEPs; groups III and IV are 'twin' and single CMEs that do not lead to large SEPs. The major findings of this paper are: first, large SEP events tend to be 'twin-CME' events. Of 59 western large SEP events in solar cycle 23, 43 are 'twin-CME' (group I) events and 16 are single-CME (group II) events. Second, not all 'twin CMEs' produced large SEPs: 28 twin CMEs did not produce large SEPs (group III events). Some of them produced excesses of particles up to a few MeV nucleon{sup -1}. Third, there were 39 single fast CMEs that did not produce SEPs (group IV events). Some of these also showed an excess of particles up to a few MeV nucleon{sup -1}. For all four groups of events, we perform statistical analyses on properties such as the angular width, the speed, the existence of accompanying metric type II radio bursts, and the associated flare class for the main CMEs and the preceding CMEs.

Ding, Liuguan; Jiang, Yong [College of Math and Physics, Nanjing University of Information Science and Technology, Nanjing, Jiangsu 210044 (China)] [College of Math and Physics, Nanjing University of Information Science and Technology, Nanjing, Jiangsu 210044 (China); Zhao, Lulu; Li, Gang, E-mail: gang.li@uah.edu [Department of Physics and CSPAR, University of Alabama in Huntsville, AL 35899 (United States)] [Department of Physics and CSPAR, University of Alabama in Huntsville, AL 35899 (United States)

2013-01-20

193

Tracking the CME-driven Shock Wave on 2012 March 5 and Radio Triangulation of Associated Radio Emission  

NASA Astrophysics Data System (ADS)

We present a multiwavelength study of the 2012 March 5 solar eruptive event, with an emphasis on the radio triangulation of the associated radio bursts. The main points of the study are reconstruction of the propagation of shock waves driven by coronal mass ejections (CMEs) using radio observations and finding the relative positions of the CME, the CME-driven shock wave, and its radio signatures. For the first time, radio triangulation is applied to different types of radio bursts in the same event and performed in a detailed way using goniopolarimetric observations from STEREO/Waves and WIND/Waves spacecraft. The event on 2012 March 5 was associated with a X1.1 flare from the NOAA AR 1429 situated near the northeast limb, accompanied by a full halo CME and a radio event comprising long-lasting interplanetary type II radio bursts. The results of the three-dimensional reconstruction of the CME (using SOHO/LASCO, STEREO COR, and HI observations), and modeling with the ENLIL cone model suggest that the CME-driven shock wave arrived at 1 AU at about 12:00 UT on March 7 (as observed by SOHO/CELIAS). The results of radio triangulation show that the source of the type II radio burst was situated on the southern flank of the CME. We suggest that the interaction of the shock wave and a nearby coronal streamer resulted in the interplanetary type II radio emission.

Magdaleni?, J.; Marqué, C.; Krupar, V.; Mierla, M.; Zhukov, A. N.; Rodriguez, L.; Maksimovi?, M.; Cecconi, B.

2014-08-01

194

Topological Evolution of a Fast Magnetic Breakout CME in 3-Dimensions  

NASA Technical Reports Server (NTRS)

W present the extension of the magnetic breakout model for CME initiation to a fully 3-dimensional, spherical geometry. Given the increased complexity of the dynamic magnetic field interactions in 3-dimensions, we first present a summary of the well known axisymmetric breakout scenario in terms of the topological evolution associated with the various phases of the eruptive process. In this context, we discuss the completely analogous topological evolution during the magnetic breakout CME initiation process in the simplest 3-dimensional multipolar system. We show that an extended bipolar active region embedded in an oppositely directed background dipole field has all the necessary topological features required for magnetic breakout, i.e. a fan separatrix surface between the two distinct flux systems, a pair of spine fieldlines, and a true 3-dimensional coronal null point at their intersection. We then present the results of a numerical MHD simulation of this 3-dimensional system where boundary shearing flows introduce free magnetic energy, eventually leading to a fast magnetic breakout CME. The eruptive flare reconnection facilitates the rapid conversion of this stored free magnetic energy into kinetic energy and the associated acceleration causes the erupting field and plasma structure to reach an asymptotic eruption velocity of greater than or approx. equal to 1100 km/s over an approx.15 minute time period. The simulation results are discussed using the topological insight developed to interpret the various phases of the eruption and the complex, dynamic, and interacting magnetic field structures.

Lynch, B. J.; Antiochos, S. K.; DeVore, C. R.; Luhmann, J. G.; Zurbuchen, T. H.

2008-01-01

195

Validation of a priori CME arrival predictions made using real-time heliospheric imager observations  

NASA Astrophysics Data System (ADS)

Between December 2010 and March 2013, volunteers for the Solar Stormwatch (SSW) Citizen Science project have identified and analyzed coronal mass ejections (CMEs) in the near real-time Solar Terrestrial Relations Observatory Heliospheric Imager observations, in order to make "Fearless Forecasts" of CME arrival times and speeds at Earth. Of the 60 predictions of Earth-directed CMEs, 20 resulted in an identifiable Interplanetary CME (ICME) at Earth within 1.5-6 days, with an average error in predicted transit time of 22 h, and average transit time of 82.3 h. The average error in predicting arrival speed is 151 km s-1, with an average arrival speed of 425km s-1. In the same time period, there were 44 CMEs for which there are no corresponding SSW predictions, and there were 600 days on which there was neither a CME predicted nor observed. A number of metrics show that the SSW predictions do have useful forecast skill; however, there is still much room for improvement. We investigate potential improvements by using SSW inputs in three models of ICME propagation: two of constant acceleration and one of aerodynamic drag. We find that taking account of interplanetary acceleration can improve the average errors of transit time to 19 h and arrival speed to 77 km s-1.

Tucker-Hood, Kimberley; Scott, Chris; Owens, Mathew; Jackson, David; Barnard, Luke; Davies, Jackie A.; Crothers, Steve; Lintott, Chris; Simpson, Robert; Savani, Neel P.; Wilkinson, J.; Harder, B.; Eriksson, G. M.; L Baeten, E. M.; Wan Wah, Lily Lau

2015-01-01

196

Reconnectionless CME Eruption: Putting the Aly-Sturrock Conjecture to Rest  

NASA Astrophysics Data System (ADS)

We demonstrate that magnetic reconnection is not necessary to initiate fast Coronal mass ejections (CMEs). The Aly-Sturrock conjecture states that the magnetic energy of a given force-free boundary field is maximized when the field is open. This is problematic for CME initiation because it leaves little or no magnetic energy to drive the eruption, unless reconnection is present to allow some of the flux to escape without opening. Thus, it has been thought that reconnection must be present to initiate CMEs. This theory has not been subject to rigorous numerical testing because conventional magnetohydrodynamics (MHD) numerical models contain numerical diffusion, which introduces uncontrolled numerical reconnection. We use a quasi-Lagrangian simulation technique to run the first controlled experiments of CME initiation in the complete lack of reconnection. We find that a flux rope confined by an arcade, when twisted beyond a critical amount, can escape to an open state, allowing some of the surrounding arcade to shrink, and releasing magnetic energy from the global field. This mechanism includes a true ideal MHD instability. We conclude that reconnection is not a necessary trigger for fast CME eruptions.

Rachmeler, L. A.; DeForest, C. E.; Kankelborg, C. C.

2009-03-01

197

Topological Evolution of a Fast Magnetic Breakout CME in Three Dimensions  

NASA Astrophysics Data System (ADS)

We present the extension of the magnetic breakout model for CME initiation to a fully three-dimensional, spherical geometry. Given the increased complexity of the dynamic magnetic field interactions in three dimensions, we first present a summary of the well known axisymmetric breakout scenario in terms of the topological evolution associated with the various phases of the eruptive process. In this context, we discuss the analogous topological evolution during the magnetic breakout CME initiation process in the simplest three-dimensional multipolar system. We show that an extended bipolar active region embedded in an oppositely directed background dipole field has all the necessary topological features required for magnetic breakout, i.e., a fan separatrix surface between the two distinct flux systems, a pair of spine field lines, and a true three-dimensional coronal null point at their intersection. We then present the results of a numerical MHD simulation of this three-dimensional system where boundary shearing flows introduce free magnetic energy, eventually leading to a fast magnetic breakout CME. The eruptive flare reconnection facilitates the rapid conversion of this stored free magnetic energy into kinetic energy and the associated acceleration causes the erupting field and plasma structure to reach an asymptotic eruption velocity of >~1100 km s-1 over an ~15 minute time period. The simulation results are discussed using the topological insight developed to interpret the various phases of the eruption and the complex, dynamic, and interacting magnetic field structures.

Lynch, B. J.; Antiochos, S. K.; DeVore, C. R.; Luhmann, J. G.; Zurbuchen, T. H.

2008-08-01

198

The 20 January 2005 CME Solar Mass Ejection Imager (SMEI) Analyses  

NASA Astrophysics Data System (ADS)

Solar Mass Ejection Imager (SMEI) brightness measurements are analyzed to determine 3D volumetric densities for several CMEs including that of the 20 January 2005 CME. Here we present analyses of these 3D heliospheric volumetric solar wind density analyses. We use this system to measure the distribution of structure and provide a 3D mass of the ejecta associated with the large CMEs viewed in SMEI observations. In the case of the 20 January 2005 CME, the primary mass moves to the northwest of the Sun following the event observed earlier in LASCO coronagraph observations. There are two other very large coronal responses to the coronal energy input beginning around 6:30 UT near the time of CME onset. One of these is the large and extremely prompt Solar Energetic Particle (SEP) proton event observed at Earth beginning about 6:50 UT. Another response is an outward-propagating fast shock that arrives at Earth 34 hours following the event onset. A response that may be attributed to this shock is observed slightly more than 5 days following this at the Ulysses spacecraft situated 5.3 AU from the Sun, 17 degrees south of the ecliptic, and 27 degrees from the Sun-Earth line to the west. SMEI observes the white-light response of this shock at Earth in the interplanetary medium around the spacecraft, and limits the shock extent in 3D.

Jackson, B. V.; Hick, P. P.; Buffington, A.

2006-12-01

199

Why Is the Great Solar Active Region 12192 CME-Poor?  

NASA Astrophysics Data System (ADS)

Solar active region (AR) 12192 of October 2014 hosts the largest sunspot group in 24 years. It is the most prolific flaring site of Cycle 24, but surprisingly produced no coronal mass ejection (CME) from the core region during its disk passage. Here, we study the magnetic conditions that prevented eruption and the consequences that ensued. We find AR 12192 to be "big but mild"; its core region exhibits weaker non-potentiality, stronger overlying field, and smaller flare-related field changes compared to two other major flare-CME-productive ARs (11429 and 11158). These differences are present in the intensive-type indices (e.g., means) but generally not the extensive ones (e.g., totals). AR 12192's large amount of magnetic free energy does not translate into CME productivity. The unexpected behavior suggests that AR eruptiveness is limited by some relative measure of magnetic non-potentiality over the restriction of background field, and that confined flares may leave weaker photospheric and coronal imprints compared to their eruptive counterparts.

Sun, Xudong; Bobra, Monica G.; Hoeksema, Todd; Liu, Yang; Li, Yan; Shen, Chenglong; Couvidat, Sebastien; Norton, Aimee A.; Fisher, George H.

2015-04-01

200

Comparison of a CME Flux-rope Model with LASCO data  

NASA Astrophysics Data System (ADS)

The theoretical flux rope model (Chen 1989, 1996) of CME dynamics is investigated and compared with height-time curves of flux rope CME observations from LASCO. This model has been shown by Krall et al. (2001) to be a good match to numerous observed CME events. It is useful to study the model parametric dependences of CME initial acceleration, which is important for understanding the driving mechanisms of the ejections. STEREO will be able to provide data of the lower parts of the corona, capturing the initial acceleration of CMEs. The physics-based flux rope model is a low dimensional model comprising two second-order ordinary differential equations for the acceleration of the height Z(t) and the minor radius a(t) for the toroidal plasma loop. Given an initial parameter vector, an MHD-stable equilibrum is found that is a partial torus with two stationary footpoints separated by a distance Sf and anchored in the massive photosphere. The equilibrium flux rope is embedded in a background corona of finite pressure pc and magnetic field Bc and balances the J × B Lorentz force, gravity, and pressure gradient force. Injection of poloidal flux (toroidal current) serves as a direct drive toward destabilization and eruption. A code solves in seconds the dynamical evolution of the system in the d=4 state space for a given set of initial physical parameters (?5 = \\{Z0,Sf,a0,\\bar{p}/pc,Bc\\}), model coronal magnetic field, model solar wind, and the functional form of the flux injection d?p(t)/dt. A physically acceptable range of parameters is sampled, and comparison with CME height-time data yields optimal parameters by the inverse method. Both the Very Fast Simulated Annealing Method (VFSA) and the Genetic Algorithm (GA) are used for optimization, and results are compared. The average relative variance of the model height versus time curves with the data sets are reported. The work is supported by NSF grant ATM-0638480 and the U.S. Department of Energy.

Pino, J. E.; Mays, M. L.; Horton, W.

2007-12-01

201

Pyomyositis after vaginal delivery  

PubMed Central

Pyomyositis is a purulent infection of skeletal muscle that arises from haematogenous spread, usually with abscess formation. It can develop after a transient bacteraemia of any cause. This type of infection has never been reported before in the literature after vaginal delivery. A 34-year-old woman had progressive severe pain in the left buttock and thigh and weakness in the left lower limb day 1 post spontaneous vaginal delivery. MRI showed severe oedema of the left gluteus, iliacus, piriformis and adductor muscles of the left thigh and a small fluid collection at the left hip joint. She was diagnosed with pyomyositis. She had fever of 37.9°C immediately postpartum and her risk factors for bacteraemia were a mild IV cannula-associated cellulitis and labour itself. She required prolonged treatment with antibiotics before significant clinical improvement was noted. PMID:22693277

Gaughan, Eve; Eogan, Maeve; Holohan, Mary

2011-01-01

202

Efficacy of an integrated continuing medical education (CME) and quality improvement (QI) program on radiation oncologist (RO) clinical practice  

SciTech Connect

Purpose: There has been little radiation oncologist (RO)-specific research in continuing medical education (CME) or quality improvement (QI) program efficacy. Our aim was to evaluate a CME/QI program for changes in RO behavior, performance, and adherence to department protocols/studies over the first 12 months of the program. Methods and Materials: The CME/QI program combined chart audit with feedback (C-AWF), simulation review AWF (SR-AWF), reminder checklists, and targeted CME tutorials. Between April 2003 and March 2004, management of 75 patients was evaluated by chart audit with feedback (C-AWF) and 178 patients via simulation review audit (SR-AWF) using a validated instrument. Scores were presented, and case management was discussed with individualized educational feedback. RO behavior and performance was compared over the first year of the program. Results: Comparing the first and second 6 months, there was a significant improvement in mean behavior (12.7-13.6 of 14, p = 0.0005) and RO performance (7.6-7.9 of 8, p = 0.018) scores. Protocol/study adherence significantly improved from 90.3% to 96.6% (p = 0.005). A total of 50 actions were generated, including the identification of learning needs to direct CME tutorials, the systematic change of suboptimal RO practice, and the alteration of deficient management of 3% of patients audited during the program. Conclusion: An integrated CME/QI program combining C-AWF, SR-AWF, QI reminders, and targeted CME tutorials effectively improved targeted RO behavior and performance over a 12-month period. There was a corresponding increase in departmental protocol and study adherence.

Leong, Cheng Nang [Department of Radiation Oncology, Cancer Institute, National University Hospital (Singapore) and Department of Radiation Oncology, Cancer Institute, Tan Tock Seng Hospital (Singapore)]. E-mail: Cheng_Nang_Leong@mail.nhg.com.sg; Shakespeare, Thomas Philip [Department of Radiation Oncology, Cancer Institute, National University Hospital (Singapore); North Coast Cancer Institute, Coffs Harbour (Australia); Mukherjee, Rahul K. [Department of Radiation Oncology, Cancer Institute, National University Hospital (Singapore); Department of Radiation Oncology, Cancer Institute, Tan Tock Seng Hospital (Singapore); Back, Michael F. [Department of Radiation Oncology, Cancer Institute, National University Hospital (Singapore); Department of Radiation Oncology, Cancer Institute, Tan Tock Seng Hospital (Singapore); Lee, Khai Mun [Department of Radiation Oncology, Cancer Institute, National University Hospital (Singapore); Department of Radiation Oncology, Cancer Institute, Tan Tock Seng Hospital (Singapore); Lu, Jiade Jay [Department of Radiation Oncology, Cancer Institute, National University Hospital (Singapore); Department of Radiation Oncology, Cancer Institute, Tan Tock Seng Hospital (Singapore); Wynne, Christopher J. [Department of Radiation Oncology, Cancer Institute, National University Hospital (Singapore); Lim, Keith [Department of Radiation Oncology, The Cancer Institute, National University Hospital (Singapore); Tang, Johann [Department of Radiation Oncology, Cancer Institute, National University Hospital (Singapore); Department of Radiation Oncology, Cancer Institute, Tan Tock Seng Hospital (Singapore); Zhang Xiaojian [Department of Radiation Oncology, Cancer Hospital, Fudan Hospital, Shanghai (China)

2006-12-01

203

Transit time of CME/shock associated with four major geo-effective CMEs in solar cycle 24  

NASA Astrophysics Data System (ADS)

The kinematics of coronal mass ejection (CME) in the interplanetary medium is very important in the concept of space-weather. Main aim of this paper is to study the propagation of four major geo-effective CMEs and their associated shocks observed in solar cycle 24. The arrival of interplanetary shocks and CMEs of these events near the Earth is seen from the ACE/wind in situ data available in OMNI data base. The CMEs considered in this study have a wide range of initial speeds 500-1900 km/s in the LASCO field of view, comprising of two slow CMEs (V ? 500 km/s), one fast CME (V ? 1800 km/s) and one moderate speed CME (V ? 800 km/s). The observed transit time of these events are compared with transit time estimated using the empirical shock arrival model (ESA). Especially, we utilize (i) different acceleration - speed equations reported in the literature from the observations made in the last few decades and (ii) various acceleration cessation distances (Acd) In addition, we compared the estimated and observed transit time with that from the Drag Based Model (DBM). From the result of this analysis, we demonstrated that each CME behaves in its own way in the interplanetary medium and their propagation is governed by the CME initial speed, interplanetary acceleration and acceleration cessation distances. In the present paper, we found (i) which acceleration equation is better for the transit time calculations (ii) importance of the CME acceleration cessation distances (iii) reducing the transit time error in CME forecasting. Based on these results and on Zhao and Dryer (2014) review (that included physics-based models), the realistic statistics should be based on real-time studies, not on post-mortem case studies.

Syed Ibrahim, M.; Shanmugaraju, A.; Bendict Lawrance, M.

2015-01-01

204

Information Delivery Options over Three Decades.  

ERIC Educational Resources Information Center

The rate of new technology-driven innovations for information delivery has accelerated over the past three decades. New information delivery formats in the 1950s and 1960s included microforms and, in response to demands from librarians, indexing and abstracting services began to make their publications available on this medium. Electronic…

Kennedy, H. Edward

1986-01-01

205

Amphiphilic polymer-mediated formation of laponite-based nanohybrids with robust stability and pH sensitivity for anticancer drug delivery.  

PubMed

The development of pH-sensitive drug delivery nanosystems that present a low drug release at the physiological pH and are able to increase the extent of the release at a lower pH value (like those existent in the interstitial space of solid tumors (pH 6.5) and in the intracellular endolysosomal compartments (pH 5.0)) is very important for an efficient and safe cancer therapy. Laponite (LP) is a synthetic silicate nanoparticle with a nanodisk structure (25 nm in diameter and 0.92 nm in thickness) and negative-charged surface, which can be used for the encapsulation of doxorubicin (DOX, a cationic drug) through electrostatic interactions and exhibit good pH sensitivity in drug delivery. However, the colloidal instability of LP still limits its potential clinical applications. In this study, we demonstrate an elegant strategy to develop stable Laponite-based nanohybrids through the functionalization of its surface with an amphiphile PEG-PLA copolymer by a self-assembly process. The hydrophobic block of PEG-PLA acts as an anchor that binds to the surface of drug-loaded LP nanodisks, maintaining the core structure, whereas the hydrophilic PEG part serves as a protective stealth shell that improves the whole stability of the nanohybrids under physiological conditions. The resulting nanocarriers can effectively load the DOX drug (the encapsulation efficiency is 85%), and display a pH-enhanced drug release behavior in a sustained way. In vitro biological evaluation indicated that the DOX-loaded nanocarriers can be effectively internalized by CAL-72 cells (an osteosarcoma cell line), and exhibit a remarkable higher anticancer cytotoxicity than free DOX. The merits of Laponite/PEG-PLA nanohybrids, such as good cytocompatibility, excellent physiological stability, sustained pH-responsive release properties, and improved anticancer activity, make them a promising platform for the delivery of other therapeutic agents beyond DOX. PMID:25167168

Wang, Guoying; Maciel, Dina; Wu, Yilun; Rodrigues, João; Shi, Xiangyang; Yuan, Yuan; Liu, Changsheng; Tomás, Helena; Li, Yulin

2014-10-01

206

COLON TARGETED DRUG DELIVERY SYSTEMS  

Microsoft Academic Search

Colon targeted drug delivery systems have the potential to deliver drugs for the treatment of a variety of colonic diseases and to deliver proteins and peptides to the colon for their systemic absorption. In recent years, various pharmaceutical approaches have been developed for targeting the drugs to the colon include, formation of prodrugs, coating of pH-sensitive polymers, use of colon

Ceyda Tuba

207

Studying the Complexity in Dynamics and Magnetic Topology of CME with 3D MHD Simulations Involving Dynamic AMR  

NASA Astrophysics Data System (ADS)

It is of fundamental importance in solar, heliospheric, and magnetospheric physics to explore the high degree of variability and complex internal magnetic and plasma structure of CMEs. Three-dimensional (3D) magnetohydrodynamic (MHD) simulations provide excellent grounds for studying the complexity in dynamics of this and other solar phenomena. We present some results on state-of-art numerical experiments of CME propagation, including dynamic Adaptive Mesh Refinement (AMR). All computations presented here are carried out using the BATS-R-US (Block Adaptive Tree Solarwind Roe Upwind Scheme) code and involve 3D MHD. The CME is initiated through an eruption of twisted flux rope in the solar corona. The MHD shock created ahead of the CME is essential in determining geoeffective events. The physics based AMR allows to reveal the complexity of the CME development and propagation on the particular ray Sun-Earth. The applied numerical algorithm is designed to use optimal computational resources for the sake of tracing CMEs with very high spatial resolution all the way from Sun to Earth, and beyond. We further discuss the differences in using various criteria for mesh refinement on the overall physical picture of the CME dynamics.

Roussev, I. I.; Manchester, W. B.; Gombosi, T. I.; De Zeeuw, D. L.; Sokolov, I. V.; Toth, G.

2002-05-01

208

Temporal and Physical Relationships Between CME Acceleration and Flare Energy Release  

NASA Astrophysics Data System (ADS)

The physical relationship between CMEs and flares is re-examined from both observational and theoretical points of view, utilizing the new SECCHI as well as LASCO observations. For the theoretical model, we use the erupting flux-rope model that has been shown to replicate observed CME trajectories. Mathematically, this model starts with an equilibrium flux rope and drives it with a specified function d?p(t)/dt increasing the poloidal flux ?p. Physically, the injected flux may be of coronal or subphotospheric origin. The function d?p/dt is parameterized by the ramp-up and ramp-down time scales, the peak duration, and the peak value. For each event, we obtain the "best fit" solution to fit the entire trajectory (out to HI1 if available) by adjusting these parameters. It is found that the duration of required poloidal flux injection is closely correlated with the duration of associated GOES X-ray profile. This correlation holds for short- duration as well as long-duration flares. This suggests that the poloidal flux injection has a physical connection to observed CME dynamics and flare energy release. Injection of poloidal flux produces an electromotive force (EMF) around the flux rope that has the same functional form and duration as d?p/dt. The EMF is sufficient to accelerate particles to several tens of keV and higher in one collisional mean free path. In the model, the main acceleration phase is governed by the intrinsic time scale (Alfvenic time in the flux rope) and the geometry (footpoint separation distance) of the flux rope, insensitive to the form of d?p/dt. The duration of the flux injection, however, is sensitive to the long-time propagation properties of the CME in HI1 field of view. The model results are compared with published results of arcade models. Work supported by ONR and NASA

Chen, J.; Kunkel, V.

2008-12-01

209

Prediction of Type II Radio Bursts Associated with Large CME Events  

NASA Astrophysics Data System (ADS)

Type II radio bursts are associated with shocks in the corona and solar wind, either driven by CMEs or else by blast waves. Recently we coupled the advanced 3D MHD BATS-R-US code of Toth, Gombosi, and colleagues with our kinetic ``bolt-on'' theory for type II emission. Initialising the simulation code with event specific coronal and CME data, the combined code can be used to predict the dynamic spectrum of type II emission for a specific radio event. We demonstrate very good agreement with Wind spacecraft observations for three type II bursts, one on 15 February 2011 and two on 7 March 2012 (associated with successive CMEs from different sides of the same active region). The intensities, frequencies, and times of fundamental and harmonic type II emission are predicted very well from the high corona to 1 AU (frequencies ~ 20 MHz - 30 kHz). The islands of increased emission correspond to different regions of the shock interacting with coronal structures, with streamers typically corresponding to reduced emission. The results provide strong evidence that both the type II theory and the BATS-R-US (driven with event-specific data) are accurate. They also provide strong evidence that the observation and detailed theoretical modelling of type II bursts can in principle provide warnings with lead-times of over a day for large and fast CMEs that might produce space weather at Earth. The MHD code can also predict whether the CME will hit Earth's magnetopause and the magnetic field direction at the magnetopause as the shock, sheath, and CME, vital quantities for predicting space weather at Earth.

Cairns, Iver; Schmidt, Joachim

210

Toward the identification of CME content needs for primary care physicians.  

PubMed

While continuing medical education (CME) has been accepted as effective in changing the clinical behavior of participants, there is still uncertainty as to the most effective method of determining content that is practice relevant and clinically important to an identified population of participating physicians. This article proposes a model for developing a knowledge examination that can be administered to CME audiences to detect deficiencies of knowledge that will be helpful in CME program planning. It further proposes that such an instrument be based upon the following assumptions: (1) that core competencies can be identified by content specialists; (2) that the relevance to practice can be determined by reviewing practitioners who represent the target audience (content and face validity); (3) that eight management stages should be sampled by the instrument to assure that all management areas of clinical practice are included; (4) that the test items be tested and retained, revised, or discarded according to the results of item analysis (validity); (5) that test items should be written to represent application and problem-solving use of knowledge; (6) that medical problems for which test items are written should be selected on the basis of potential for improving mortality or morbidity. For example, in the case of cancer, most would agree that colorectal cancer represents an area where better application of current concepts would result in improved mortality rates. With use of a test instrument constructed on the basis of these assumptions, it should be possible to sample what physicians need to know that is relevant to their practices--the proactive model.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2641344

Williams, T; Donaldson, W S

1989-01-01

211

Comparison of the WSA-ENLIL model with three CME cone types  

NASA Astrophysics Data System (ADS)

We have made a comparison of the CME-associated shock propagation based on the WSA-ENLIL model with three cone types using 29 halo CMEs from 2001 to 2002. These halo CMEs have cone model parameters as well as their associated interplanetary (IP) shocks. For this study we consider three different cone types (an asymmetric cone model, an ice-cream cone model and an elliptical cone model) to determine 3-D CME parameters (radial velocity, angular width and source location), which are the input values of the WSA-ENLIL model. The mean absolute error (MAE) of the arrival times for the asymmetric cone model is 10.6 hours, which is about 1 hour smaller than those of the other models. Their ensemble average of MAE is 9.5 hours. However, this value is still larger than that (8.7 hours) of the empirical model of Kim et al. (2007). We will compare their IP shock velocities and densities with those from ACE in-situ measurements and discuss them in terms of the prediction of geomagnetic storms.Abstract (2,250 Maximum Characters): We have made a comparison of the CME-associated shock propagation based on the WSA-ENLIL model with three cone types using 29 halo CMEs from 2001 to 2002. These halo CMEs have cone model parameters as well as their associated interplanetary (IP) shocks. For this study we consider three different cone types (an asymmetric cone model, an ice-cream cone model and an elliptical cone model) to determine 3-D CME parameters (radial velocity, angular width and source location), which are the input values of the WSA-ENLIL model. The mean absolute error (MAE) of the arrival times for the asymmetric cone model is 10.6 hours, which is about 1 hour smaller than those of the other models. Their ensemble average of MAE is 9.5 hours. However, this value is still larger than that (8.7 hours) of the empirical model of Kim et al. (2007). We will compare their IP shock velocities and densities with those from ACE in-situ measurements and discuss them in terms of the prediction of geomagnetic storms.

Jang, Soojeong; Moon, Y.; Na, H.

2013-07-01

212

The Driving Magnetic Field and Reconnection in CME/Flare Eruptions and Coronal Jets  

NASA Technical Reports Server (NTRS)

Signatures of reconnection in major CME (coronal mass ejection)/flare eruptions and in coronal X-ray jets are illustrated and interpreted. The signatures are magnetic field lines and their feet that brighten in flare emission. CME/flare eruptions are magnetic explosions in which: 1. The field that erupts is initially a closed arcade. 2. At eruption onset, most of the free magnetic energy to be released is not stored in field bracketing a current sheet, but in sheared field in the core of the arcade. 3. The sheared core field erupts by a process that from its start or soon after involves fast "tether-cutting" reconnection at an initially small current sheet low in the sheared core field. If the arcade has oppositely-directed field over it, the eruption process from its start or soon after also involves fast "breakout" reconnection at an initially small current sheet between the arcade and the overarching field. These aspects are shown by the small area of the bright field lines and foot-point flare ribbons in the onset of the eruption. 4. At either small current sheet, the fast reconnection progressively unleashes the erupting core field to erupt with progressively greater force. In turn, the erupting core field drives the current sheet to become progressively larger and to undergo progressively greater fast reconnection in the explosive phase of the eruption, and the flare arcade and ribbons grow to become comparable to the pre-eruption arcade in lateral extent. In coronal X-ray jets: 1. The magnetic energy released in the jet is built up by the emergence of a magnetic arcade into surrounding unipolar "open" field. 2. A simple jet is produced when a burst of reconnection occurs at the current sheet between the arcade and the open field. This produces a bright reconnection jet and a bright reconnection arcade that are both much smaller in diameter that the driving arcade. 3. A more complex jet is produced when the arcade has a sheared core field and undergoes an ejective eruption in the manner of a miniature CME/flare eruption. The jet is then a combination of a miniature CME and the products of more widely distributed reconnection of the erupting arcade with the open field than in simple jets.

Moore, Ronald L.

2010-01-01

213

AIA observations of a flare/CME system in conjunction with X-ray and radio data  

NASA Astrophysics Data System (ADS)

During solar flares and coronal mass ejections, free magnetic energy, previously stored within the magnetic field, is released and used to accelerate particles and heat the surrounding plasma. Using multiwavelength observations from AIA onboard SDO, combined with X-ray observations from RHESSI and radio observations from the Nancay Radioheliograph we investigate sources of particle acceleration and heating within the flare-CME system of an event which occurred on the 14 August 2010. This was the first proton event in more than three years. In addition, radio spectrogram data show Type III radio bursts associated with the impulsive/launch phase of the CME, indicating the location of energetic electrons as they escape into the interplanetary medium. A Type II radio burst is also observed as electrons are accelerated in a CME driven shock as the ejected material propagates away from the Sun.

Bain, H. M.; Krucker, S.

2010-12-01

214

Multi-wavelength observations of CME-associated structures on the Sun with the CORONAS-F/SPIRIT EUV telescope  

NASA Astrophysics Data System (ADS)

Multi-wavelength imaging of the solar corona is a powerful observational method to study CME-related dynamics of structures in spectral bands related to the solar corona and transition region. We analyze large-scale eruptive events caused by halo-type CMEs observed at the solar disk with the CORONAS-F/SPIRIT (175, 304, and 284 Å) and SOHO/EIT telescopes on November 4, 2001 and October-November, 2003. For most events, CME-associated dimmings coincide in different bands, but the 304 Å dimming in November 4, 2001 event was delayed by >1/2 hours. In October-November events, coronal waves were observed in 195 Å and some in 175 Å channel. In a CME event associated with a filament eruption on November 18, the SPIRIT images display a propagating disturbance seen as a darkening in 304 Å channel only. This phenomenon was not described earlier.

Slemzin, V.; Chertok, I.; Grechnev, V.; Ignat'ev, A.; Kuzin, S.; Pertsov, A.; Zhitnik, I.; Delaboudinière, J.-P.

215

Plasma properties from the multi-wavelength analysis of the November 1st 2003 CME/shock event  

PubMed Central

The analysis of the spectral properties and dynamic evolution of a CME/shock event observed on November 1st 2003 in white-light by the LASCO coronagraph and in the ultraviolet by the UVCS instrument operating aboard SOHO, has been performed to compute the properties of some important plasma parameters in the middle corona below about 2R?. Simultaneous observations obtained with the MLSO/Mk4 white-light coronagraph, providing both the early evolution of the CME expansion in the corona and the pre-shock electron density profile along the CME front, were also used to study this event. By combining the above information with the analysis of the metric type II radio emission detected by ground-based radio spectrographs, we finally derive estimates of the values of the local Alfvén speed and magnetic field strength in the solar corona. PMID:25685432

Benna, Carlo; Mancuso, Salvatore; Giordano, Silvio; Gioannini, Lorenzo

2012-01-01

216

Plasma properties from the multi-wavelength analysis of the November 1st 2003 CME/shock event.  

PubMed

The analysis of the spectral properties and dynamic evolution of a CME/shock event observed on November 1st 2003 in white-light by the LASCO coronagraph and in the ultraviolet by the UVCS instrument operating aboard SOHO, has been performed to compute the properties of some important plasma parameters in the middle corona below about 2R ?. Simultaneous observations obtained with the MLSO/Mk4 white-light coronagraph, providing both the early evolution of the CME expansion in the corona and the pre-shock electron density profile along the CME front, were also used to study this event. By combining the above information with the analysis of the metric type II radio emission detected by ground-based radio spectrographs, we finally derive estimates of the values of the local Alfvén speed and magnetic field strength in the solar corona. PMID:25685432

Benna, Carlo; Mancuso, Salvatore; Giordano, Silvio; Gioannini, Lorenzo

2013-05-01

217

Ion acceleration at CME-driven shocks near the Earth and the Sun  

SciTech Connect

We compare the behavior of heavy ion spectra during an Energetic Storm Particle (ESP) event that exhibited clear evidence of wave excitation with that observed during an intense, large gradual Solar Energetic Particle (SEP) event in which the associated <0.2 MeV/nucleon ions are delayed >12 hr. We interpret that the ESP event is an example of the first-order Fermi acceleration process where enhancements in the magnetic field power spectral densities around local ion cyclotron frequency {nu}{sub pc} indicate the presence of Alfven waves excited by accelerated protons streaming away from the in-situ interplanetary shock. The softening or unfolding of the CNO energy spectrum below {approx}200 keV/nucleon and the systematic organization of the Fe and O spectral roll-overs with the E/q ratio during the ESP event are likely due to M/Q-dependent trapping and scattering of the heavy ions by the proton-excited waves. Based on striking similarities in the spectral behavior observed upstream of both, the ESP and the SEP event, we suggest that coupling between proton-generated Alfven waves and energetic ions is also operating at the distant CME shock during the large, gradual SEP event, thereby providing us with a new, powerful tool to remotely probe the roles of shock geometries and wave-particle interactions at near-Sun CME-driven shocks.

Desai, Mihir; Dayeh, Maher; Ebert, Robert; Smith, Charles; Mason, Glenn; Li, G. [Southwest Research Institute, 6220 Culebra Road, San Antonio, Texas, 78238 (United States); University of New Hampshire, Durham, New Hampshire, 03824 (United States); Applied Physics Laboratory, Johns Hopkins University, Laurel, Maryland, 20724 (United States); Center for Space Plasma and Aeronomic Research, University of Alabama, Huntsville, Al 35899 (United States)

2012-11-20

218

The Divergence of CME and Sunspot Number Rates During Solar Cycle 24  

NASA Astrophysics Data System (ADS)

In the previous three solar cycles the frequency of occurrence of CMEs observed in white light has closely tracked the solar cycle in both phase and amplitude, varying by an order of magnitude over the cycle. LASCO has now observed the entire solar Cycle 23 and continues to observe through the current rise and maximum phases of Cycle 24. Cycle 23 had an unusually long decline and extended minimum. During this period we have been able to image and count CMEs in the heliosphere, and can determine rates from both LASCO and STEREO SECCHI (since 2007) coronagraphs and from the Solar Mass Ejection Imager (SMEI - since 2003) and the SECCHI Heliospheric Imagers in the heliosphere. Manual rates estimated by observers are now supplemented by counts from identifications made by automatic programs, such as contained in the SEEDS, CACTus and ARTEMIS catalogs. Since the cycle 23/24 minimum, the CME and sunspot number rates have diverged, with similar cycle 23/24 rise and peak CME rates but much lower SSN rates in this cycle. We will discuss these rate estimates and their implications for the evolution of the global solar magnetic field.

Webb, David F.; St. Cyr, Orville Chris; Xie, Hong; Kuchar, Thomas Andrew

2014-06-01

219

PROPAGATION AND EVOLUTION OF THE JUNE 1st 2008 CME IN THE INTERPLANETARY MEDIUM  

NASA Astrophysics Data System (ADS)

In this work we present a study of the coronal mass ejection (CME) of June 1st of 2008 in the interplanetary medium. This event has been extensively studied by others because of its favorable geometry and the possible consequences of its peculiar initiation for space weather forecasting. We show an analysis of the evolution of the CME in the interplanetary medium in order to shed some light on the propagation mechanism of the ICME. We have determined the typical shock associated characteristics of the ICME in order to understand the propagation properties. Using two different non force-free models of the magnetic cloud allows us to incorporate expansion of the cloud. We use in-situ measurements from STEREO B/IMPACT to characterize the ICME. In addition, we use images from STEREO A/SECCHI-HI to analyze the propagation and visual evolution of the associated flux rope in the interplanetary medium. We compare and contrast these observations with the results of the analytical models.

Nieves-Chinchilla, T.; Lamb, D. A.; Davila, J. M.; Vinas, A. F.; Moestl, C.; Hidalgo, M. A.; Farrugia, C. J.; Malandraki, O.; Dresing, N.; Gómez-Herrero, R.

2009-12-01

220

Longitudinal Dependence of SEP Peak Intensities as Evidence of CME-Driven Shock Particle Acceleration  

NASA Astrophysics Data System (ADS)

Multi-spacecraft observations of solar energetic particle (SEP) events allow us to estimate the longitudinal distributions of SEP peak intensities. By fitting a Gaussian functional form to the ensemble of SEP peak intensities measured by two or more spacecraft as a function of the longitudinal distance between the associated parent solar flare and the footpoint labels of the magnetic field lines connecting each spacecraft with the Sun, we found that such distributions are not centered at nominal well-connected flare longitudes but slightly offset to the west of the associated flare (Lario et al. 2006, 2013). We offer an interpretation of this result in terms of long-lived particle injection from shocks driven by the associated coronal mass ejections (CMEs). By assuming that (i) CME-driven shocks are centered on the longitude of the associated solar flare, (ii) the injection of shock accelerated particles maximizes at the nose of the shock which propagates radially outward from the Sun, and (iii) SEP particle injection from the shock starts at a certain distance above the solar surface, we infer an average radial distance where shocks are located when peak intensities in the prompt component of the SEP events are observed. We estimate the heliocentric distance of the CME-driven shock when particle injection from the shock maximizes and conclude that the injection of ˜20 MeV protons and near-relativistic electrons maximizes well inside ˜0.2 AU.

Lario, D.; Roelof, E. C.; Decker, R. B.

2014-05-01

221

UThe life of a CME and the development of a MIR: From the Sun to 58 A J. D. Richardson, K. I. Paularena, and C. Wang  

E-print Network

1 UThe life of a CME and the development of a MIR: From the Sun to 58 A J. D. Richardson, K. I interac- h tion regions (MIRs). One signature of some CMEs that can be used to track them through t MIR. This study is the first to identify a CME source and use increased alpha abundance t race

Richardson, John

222

The effect of rhBMP-2 and PRP delivery by biodegradable ?-tricalcium phosphate scaffolds on new bone formation in a non-through rabbit cranial defect model  

PubMed Central

This study evaluated whether the combination of biodegradable ?-tricalcium phosphate (?-TCP) scaffolds with recombinant human bone morphogenetic protein-2 (rhBMP-2) or platelet-rich plasma (PRP) could accelerate bone formation and increase bone height using a rabbit non-through cranial bone defect model. Four non-through cylindrical bone defects with a diameter of 8-mm were surgically created on the cranium of rabbits. ?-TCP scaffolds in the presence and absence of impregnated rhBMP-2 or PRP were placed into the defects. At 8 and 16 weeks after implantation, samples were dissected and fixed for analysis by microcomputed tomography and histology. Only defects with rhBMP-2 impregnated ?-TCP scaffolds showed significantly enhanced bone formation compared to non-impregnated ?-TCP scaffolds (p<0.05). Although new bone was higher than adjacent bone at 8 weeks after implantation, vertical bone augmentation was not observed at 16 weeks after implantation, probably due to scaffold resorption occurring concurrently with new bone formation. PMID:23779152

Lim, Hyun-Pil; Mercado-Pagan, Angel E.; Yun, Kwi-Dug; Kang, Seong-Soo; Choi, Taek-Hue; Bishop, Julius; Koh, Jeong-Tae; Maloney, William; Lee, Kwang-Min; Yang, Yunzhi; Park, Sang-Won

2013-01-01

223

The Role of the IMF in Forecasting CME-Induced Terrestrial Space Weather  

NASA Astrophysics Data System (ADS)

The interplanetary magnetic field (IMF) is the major contributor to terrestrial space weather induced by coronal mass ejections (CME). Nowcasting of these events has become quite successful. Our ability to forecast such events on significant time scales (on the order of one day), however, remains a rather elusive goal. In situ observations of the solar wind at the L1 point provide an advance warning of no more than 1 hour. The auto-correlation times of the solar wind are usually too short to enable data driven predictions with sufficient lead times. The resolution of both solar wind propagation modeling from Sun to Earth and solar remote sensing observations is insufficient to predict the CME internal structure at the level needed to predict terrestrial space weather conditions. A practical terrestrial space weather forecast for CMEs will require an integrated approach where remote sensing, modeling and in situ components work together to make the resulting framework stronger than the sum of the individual parts. In this presentation, we will concentrate on in situ observations of the IMF viewed in this context. Ultimately, our goal is to enable the development of integrated, data-driven space weather forecasting. For this, we need to understand the temporal patterns of the IMF inside CMEs at relevant time scales. To uncover these patterns we are classifying solar wind time series segments of various lengths using specially trained neural networks (Kohonen Self-Organizing Maps). We present how well our networks can classify CMEs and their subclasses as a function of the length of these time series segments and the variable types (IMF, solar wind properties) we use. Then we discuss the probability with which the future temporal development of the solar wind can be predicted using those time segment patterns. To close the presentation, we discuss how we envision to correlate our purely empirical CME time segment classifications of the IMF and solar wind measurements with remote sensing solar observations. Combining these correlations with solar wind propagation estimates could lead to probability estimates of IMF temporal developments at L1 and Earth based on remote sensing solar observations alone.

Jahn, J.; Elliott, H. A.

2009-12-01

224

Continuing Medical Education (CME) www.princetonhcs.org A University Hospital Affiliate of UMDNJ Robert Wood Johnson Medical School  

E-print Network

­ Robert Wood Johnson Medical School The Office of Continuing Medical Education presents the DepartmentContinuing Medical Education (CME) www.princetonhcs.org A University Hospital Affiliate of UMDNJ Medicine Princeton HealthCare System is accredited by the Medical Society of New Jersey to provide

Rowley, Clarence W.

225

Simulation of the 23 July 2012 extreme space weather event: What if this extremely rare CME was Earth directed?  

NASA Astrophysics Data System (ADS)

Extreme space weather events are known to cause adverse impacts on critical modern day technological infrastructure such as high-voltage electric power transmission grids. On 23 July 2012, NASA's Solar Terrestrial Relations Observatory-Ahead (STEREO-A) spacecraft observed in situ an extremely fast coronal mass ejection (CME) that traveled 0.96 astronomical units (˜1 AU) in about 19 h. Here we use the Space Weather Modeling Framework (SWMF) to perform a simulation of this rare CME. We consider STEREO-A in situ observations to represent the upstream L1 solar wind boundary conditions. The goal of this study is to examine what would have happened if this Rare-type CME was Earth-bound. Global SWMF-generated ground geomagnetic field perturbations are used to compute the simulated induced geoelectric field at specific ground-based active INTERMAGNET magnetometer sites. Simulation results show that while modeled global SYM-H index, a high-resolution equivalent of the Dst index, was comparable to previously observed severe geomagnetic storms such as the Halloween 2003 storm, the 23 July CME would have produced some of the largest geomagnetically induced electric fields, making it very geoeffective. These results have important practical applications for risk management of electrical power grids.

Ngwira, Chigomezyo M.; Pulkkinen, Antti; Leila Mays, M.; Kuznetsova, Maria M.; Galvin, A. B.; Simunac, Kristin; Baker, Daniel N.; Li, Xinlin; Zheng, Yihua; Glocer, Alex

2013-12-01

226

Relation Between the 3D-Geometry of the Coronal Wave and Associated CME During the 26 April 2008 Event  

NASA Technical Reports Server (NTRS)

We study the kinematical characteristics and 3D geometry of a large-scale coronal wave that occurred in association with the 26 April 2008 flare-CME event. The wave was observed with the EUVI instruments aboard both STEREO spacecraft (STEREO-A and STEREO-B) with a mean speed of approx 240 km/s. The wave is more pronounced in the eastern propagation direction, and is thus, better observable in STEREO-B images. From STEREO-B observations we derive two separate initiation centers for the wave, and their locations fit with the coronal dimming regions. Assuming a simple geometry of the wave we reconstruct its 3D nature from combined STEREO-A and STEREO-B observations. We find that the wave structure is asymmetric with an inclination toward East. The associated CME has a deprojected speed of approx 750 +/- 50 km/s, and it shows a non-radial outward motion toward the East with respect to the underlying source region location. Applying the forward fitting model developed by Thernisien, Howard, and Vourlidas we derive the CME flux rope position on the solar surface to be close to the dimming regions. We conclude that the expanding flanks of the CME most likely drive and shape the coronal wave.

Temmer, M.; Veronig, A. M.; Gopalswamy, N.; Yashiro, S.

2011-01-01

227

18XZ Tauri and the Super CME! These pictures were taken by the Hubble Space Telescope between 1995  

E-print Network

18XZ Tauri and the Super CME! These pictures were taken by the Hubble Space Telescope between 1995 gas in events called Coronal Mass Ejections (CMEs) but involve far less matter ejected into space present in the star's interplanetary space? Space Math http://spacemath.gsfc.nasa.gov #12;18 Answer Key

228

C-ME: A 3D Community-Based, Real-Time Collaboration Tool for Scientific Research and Training  

PubMed Central

The need for effective collaboration tools is growing as multidisciplinary proteome-wide projects and distributed research teams become more common. The resulting data is often quite disparate, stored in separate locations, and not contextually related. Collaborative Molecular Modeling Environment (C-ME) is an interactive community-based collaboration system that allows researchers to organize information, visualize data on a two-dimensional (2-D) or three-dimensional (3-D) basis, and share and manage that information with collaborators in real time. C-ME stores the information in industry-standard databases that are immediately accessible by appropriate permission within the computer network directory service or anonymously across the internet through the C-ME application or through a web browser. The system addresses two important aspects of collaboration: context and information management. C-ME allows a researcher to use a 3-D atomic structure model or a 2-D image as a contextual basis on which to attach and share annotations to specific atoms or molecules or to specific regions of a 2-D image. These annotations provide additional information about the atomic structure or image data that can then be evaluated, amended or added to by other project members. PMID:18286178

Kolatkar, Anand; Kennedy, Kevin; Halabuk, Dan; Kunken, Josh; Marrinucci, Dena; Bethel, Kelly; Guzman, Rodney; Huckaby, Tim; Kuhn, Peter

2008-01-01

229

Particle acceleration and transport at an oblique CME-driven shock  

NASA Astrophysics Data System (ADS)

In gradual solar energetic particle (SEP) events, protons and heavy ions are often accelerated to >100 MeV/nucleon at a CME-driven shock. In this work, we study particle acceleration at an oblique shock by extending our earlier particle acceleration and transport in heliosphere (PATH) code to include shocks with arbitrary ?BN, where ?BN is the angle between the upstream magnetic field and the shock normal. Instantaneous particle spectra at the shock front are obtained by solving the transport equation using the total diffusion coefficient ?, which is a function of the parallel diffusion coefficient ?? and the perpendicular diffusion coefficient ??. In computing ?? and ??, we use analytic expressions derived previously. The particle maximum energy at the shock front as a function of time, the time intensity profiles and particle spectra at 1 AU for five ?BN's are calculated for an example shock.

Li, G.; Shalchi, A.; Ao, X.; Zank, G.; Verkhoglyadova, O. P.

2012-03-01

230

Comparison of CME radial velocities from a flux rope model and an ice cream cone model  

NASA Astrophysics Data System (ADS)

Coronal Mass Ejections (CMEs) on the Sun are the largest energy release process in the solar system and act as the primary driver of geomagnetic storms and other space weather phenomena on the Earth. So it is very important to infer their directions, velocities and three-dimensional structures. In this study, we choose two different models to infer radial velocities of halo CMEs since 2008 : (1) an ice cream cone model by Xue et al (2005) using SOHO/LASCO data, (2) a flux rope model by Thernisien et al. (2009) using the STEREO/SECCHI data. In addition, we use another flux rope model in which the separation angle of flux rope is zero, which is morphologically similar to the ice cream cone model. The comparison shows that the CME radial velocities from among each model have very good correlations (R>0.9). We will extending this comparison to other partial CMEs observed by STEREO and SOHO.

Kim, T.; Moon, Y.; Na, H.

2011-12-01

231

Dependence of Sunspot Properties on Flare Occurrence and Flare-CME Association  

NASA Astrophysics Data System (ADS)

Previous studies showed that the intense flares tend to erupt from the large sunspot region with complex magnetic configuration and strong magnetic field. However, note that not all the active regions (ARs) classified as ??? would produce X-class flares. To clarify the significance of sunspot properties on solar explosive events, we reexamine the dependence of flare magnitude on sunspot size and magnetic type during 1996-2014 based on the report of NOAA Solar Region Summary and the measurements of GOES soft X-ray flux. In particular, we focus on the ???-type ARs to relate the flare productivity to the sunspot area and magnetic field strength by means of the line-of-sight magnetograms from SOHO/MDI and SDO/HMI. Two flare-productive ARs, 10486 and 12192, with ??? magnetic configuration during most periods of their disk passages are further investigated to characterize the sunspots and flare-CME association.

Yang, Ya-Hui

2015-04-01

232

Transdermal drug delivery  

Microsoft Academic Search

Transdermal drug delivery has made an important contribution to medical practice, but has yet to fully achieve its potential as an alternative to oral delivery and hypodermic injections. First-generation transdermal delivery systems have continued their steady increase in clinical use for delivery of small, lipophilic, low-dose drugs. Second-generation delivery systems using chemical enhancers, noncavitational ultrasound and iontophoresis have also resulted

Mark R Prausnitz; Robert Langer

2008-01-01

233

CME liftoff with high-frequency fragmented type II burst emission  

E-print Network

Aims: Solar radio type II bursts are rarely seen at frequencies higher than a few hundred MHz. Since metric type II bursts are thought to be signatures of propagating shock waves, it is of interest to know how these shocks, and the type II bursts, are formed. In particular, how are high-frequency, fragmented type II bursts created? Are there differences in shock acceleration or in the surrounding medium that could explain the differences to the "typical" metric type IIs? Methods: We analyse one unusual metric type II event in detail, with comparison to white-light, EUV, and X-ray observations. As the radio event was associated with a flare and a coronal mass ejection (CME), we investigate their connection. We then utilize numerical MHD simulations to study the shock structure induced by an erupting CME in a model corona including dense loops. Results: Our simulations show that the fragmented part of the type II burst can be formed when a coronal shock driven by a mass ejection passes through a system of dense loops overlying the active region.To produce fragmented emission, the conditions for plasma emission have to be more favourable inside the loop than in the interloop area. The obvious hypothesis, consistent with our simulation model, is that the shock strength decreases significantly in the space between the denser loops. The later, more typical type II burst appears when the shock exits the dense loop system and finally, outside the active region, the type II burst dies out when the changing geometry no longer favours the electron shock-acceleration.

S. Pohjolainen; J. Pomoell; R. Vainio

2008-09-02

234

Are CME-Related Dimmings Always a Simple Signature of Interplanetary Magnetic Cloud Footpoints?  

NASA Astrophysics Data System (ADS)

Coronal dimmings are often present on both sides of erupting magnetic configurations. It has been suggested that dimmings mark the location of the footpoints of ejected flux ropes and, thus, their magnetic flux can be used as a proxy for the flux involved in the ejection. If so, this quantity can be compared to the flux in the associated interplanetary magnetic cloud to find clues about the origin of the ejected flux rope. In the context of this physical interpretation, we analyze the event, flare, and coronal mass ejection (CME) that occurred in active region 10486 on 28 October 2003. The CME on this day is associated with large-scale dimmings, located on either side of the main flaring region. We combine SOHO/Extreme Ultraviolet Imaging Telescope data and Michelson Doppler Imager magnetic maps to identify and measure the flux in the dimming regions. We model the associated cloud and compute its magnetic flux using in situ observations from the Magnetometer Instrument and the Solar Wind Electron Proton Alpha Monitor aboard the Advance Composition Explorer. We find that the magnetic fluxes of the dimmings and magnetic cloud are incompatible, in contrast to what has been found in previous studies. We conclude that, in certain cases, especially in large-scale events and eruptions that occur in regions that are not isolated from other flux concentrations, the interpretation of dimmings requires a deeper analysis of the global magnetic configuration, since at least a fraction of the dimmed regions is formed by reconnection between the erupting field and the surrounding magnetic structures.

Mandrini, C. H.; Nakwacki, M. S.; Attrill, G.; van Driel-Gesztelyi, L.; Démoulin, P.; Dasso, S.; Elliott, H.

2007-08-01

235

On-board CME detection algorithm for the Solar Orbiter-METIS coronagraph  

NASA Astrophysics Data System (ADS)

The METIS coronagraph is one of the instruments part of the payload of the ESA - Solar Orbiter mission to be launched in 2017. The spacecraft will operate much like a planetary encounter mission, with the main scientific activity taking place with the remote-sensing instruments during three 10-days intervals per orbit: optimization of the different instrument observing modes will be crucial. One of the key scientific targets of METIS will be the study of transient ejections of mass through the solar corona (Coronal Mass Ejections - CMEs) and their heliospheric evolution. METIS will provide for the first time imaging of CMEs in two different wavelengths: VL (visible light 580- 640 nm) and UV (Lyman-? line of HI at 121.6 nm). The detection of transient phenomena shall be managed directly by the METIS Processing and Power Unit (MPPU) by means of both external triggers ("flags") coming from other Solar Orbiter instruments, and internal "flags" produced directly by the METIS on-board software. METIS on-board algorithm for the automatic detection of CMEs will be based on running differences between consecutive images re-binned to very low resolution and thresholded for significant changes over a minimum value. Given the small relative variation of white light intensity during CMEs, the algorithm will take advantage of VL images acquired with different polarization angles to maximize the detection capability: possible false detections should be automatically managed by the algorithm. The algorithm will be able to provide the CME first detection time, latitudinal direction of propagation on the plane of the sky (within 45 degrees), a binary flag indicating whether a "halo CME" has been detected.

Bemporad, A.; Andretta, V.; Pancrazzi, M.; Focardi, M.; Straus, T.; Sasso, C.; Spadaro, D.; Uslenghi, M.; Antonucci, E.; Fineschi, S.; Abbo, L.; Nicolini, G.; Landini, F.; Romoli, M.; Naletto, G.; Nicolosi, P.

2014-07-01

236

Wavelet analysis of CME, X-ray flare, and sunspot series  

NASA Astrophysics Data System (ADS)

Context. Coronal mass ejections (CMEs) and solar flares are the most energetic transient phenomena taking place at the Sun. Together they are principally responsible for disturbances in outer geospace. Coronal mass ejections and solar flares are believed to be correlated with the solar cycle, which is mainly characterized by sunspot numbers. Aims: Here, we search for pattern identification in CMEs, X-ray solar flares, and sunspot number time series using a new data mining process and a quantitative procedure to correlate these series. Methods: This new process consists of the combination of a decomposition method with the wavelet transform technique applied to the series ranging from 2000 until 2012. A simple moving average is used for the time-series decomposition as a high-pass filter. A continuous wavelet transform is applied to the series in sequence, which permits us to uncover signals previously masked by the original time series. We made use of the wavelet coherence to find some correlation between the data. Results: The results have shown the existence of periodic and intermittent signals in the CMEs, flares, and sunspot time series. For the CME and flare series, few and relatively short time intervals without any signal were observed. Signals with an intermittent character take place during some epochs of the maximum and descending phases of the solar cycle 23 and rising phase of solar cycle 24. A comparison among X-ray flares, sunspots, and CME time series shows a stronger relation between flare and CMEs, although during some short intervals (four-eight months) and in a relatively narrow band. Yet, in contrast we have obtained a fainter or even absent relation between the X-ray flares and sunspot number series as well as between the CMEs and sunspot number series.

Guedes, M. R. G.; Pereira, E. S.; Cecatto, J. R.

2015-01-01

237

The Relationship Between CME Properties in the CDAW, CACTUS and SEEDS Catalogs and ?25 MeV Solar Proton Event Intensities  

NASA Astrophysics Data System (ADS)

The existence of a correlation between the intensity of solar energetic proton (SEP) events and the speed of the associated coronal mass ejection near the Sun is well known, and is often interpreted as evidence for particle acceleration at CME-driven shocks. However, this correlation is far from perfect and might be improved by taking other parameters into consideration (e.g., CME width). In studies of cycle 23 SEP events, values of CME speed, width and other parameters were typically taken from the CDAWWeb LASCO CME catalog. This is compiled 'by hand' from examination of LASCO images by experienced observers. Other automated LASCO CME catalogs have now been developed, e.g., CACTUS (Royal Observatory of Belgium) and SEEDS (George Mason University), but the basic CME parameters do not always agree with those from the CDAWweb catalog since they are not determined in the same way. For example the 'CME speed' might be measured at a specific position angle against the plane of the sky in one catalog, or be the average of speeds taken along the CME front in another. Speeds may also be based on linear or higher order fits to the coronagraph images. There will also be projection effects in these plane of the sky speeds. Similarly, CME widths can vary between catalogs and are dependent on how they are defined. For example, the CDAW catalog lists any CME that surrounds the occulting disk as a 'halo' (360 deg. width) CME even though the CME may be highly-asymmetric and originate from a solar event far from central meridian. Another catalog may give a smaller width for the same CME. The problem of obtaining the 'true' CME width is especially acute for assessing the relationship between CME width and SEP properties when using the CDAW catalog since a significant fraction, if not the majority, of the CMEs associated with major SEP events are reported to be halo CMEs. In principle, observations of CMEs from the STEREO A and B spacecraft, launched in late 2006, might be used to overcome some of these problems. In particular, a spacecraft in quadrature with the solar source of an SEP event should observe the 'true' width and speed of the associated CME. However, STEREO CME parameters are derived using the CACTUS method, and cannot be directly compared with the LASCO CDAW catalog values that have been so widely used for many years. In this study, we will examine the relationship between the properties of CMEs in various catalogs and the intensities of a large sample of particle events that include ˜25 MeV protons in cycles 23 and 24. In particular, we will compare the proton intensity-speed relationships obtained using the CDAW, CACTUS and SEEDS LASCO catalogs, and also using the CACTUS values from whichever spacecraft (STEREO A, B or SOHO) is best in quadrature with the solar event. We will also examine whether there is any correlation between the width of the CMEs in the automated catalogs and proton intensity, and whether a combination of CME speed and width might improve the correlation with proton intensity.

Richardson, I. G.; von Rosenvinge, T. T.; Cane, H. V.

2013-12-01

238

Transdermal drug delivery  

PubMed Central

Transdermal drug delivery has made an important contribution to medical practice, but has yet to fully achieve its potential as an alternative to oral delivery and hypodermic injections. First-generation transdermal delivery systems have continued their steady increase in clinical use for delivery of small, lipophilic, low-dose drugs. Second-generation delivery systems using chemical enhancers, non-cavitational ultrasound and iontophoresis have also resulted in clinical products; the ability of iontophoresis to control delivery rates in real time provides added functionality. Third-generation delivery systems target their effects to skin’s barrier layer of stratum corneum using microneedles, thermal ablation, microdermabrasion, electroporation and cavitational ultrasound. Microneedles and thermal ablation are currently progressing through clinical trials for delivery of macromolecules and vaccines, such as insulin, parathyroid hormone and influenza vaccine. Using these novel second- and third-generation enhancement strategies, transdermal delivery is poised to significantly increase impact on medicine. PMID:18997767

Prausnitz, Mark R.; Langer, Robert

2009-01-01

239

Using Heliospheric Imaging for Storm Forecasting - SMEI CME Observations as a Tool for Operational Forecasting at AFWA  

NASA Astrophysics Data System (ADS)

Observations of coronal mass ejections (CMEs) from heliospheric imagers such as the Solar Mass Ejection Imager (SMEI) can lead to significant improvements in operational space weather forecasting. We are working with the Air Force Weather Agency (AFWA) to ingest SMEI all-sky imagery with appropriate tools to help forecasters improve their operational space weather forecasts. We describe two approaches: 1) Near- real time analysis of propagating CMEs from SMEI images alone combined with near-Sun observations of CME onsets and, 2) Using these calculations of speed as a mid-course correction to the HAFv2 solar wind model forecasts. HAFv2 became operational at AFWA in late 2006. The objective is to determine a set of practical procedures that the duty forecaster can use to update or correct a solar wind forecast using heliospheric imager data. SMEI observations can be used inclusively to make storm forecasts, as recently discussed in Webb et al. (Space Weather, in press, 2008). We have developed a point-and-click analysis tool for use with SMEI images and are working with AFWA to ensure that timely SMEI images are available for analyses. When a frontside solar eruption occurs, especially if within about 45 deg. of Sun center, a forecaster checks for an associated CME observed by a coronagraph within an appropriate time window. If found, especially if the CME is a halo type, the forecaster checks SMEI observations about a day later, depending on the apparent initial CME speed, for possibly associated CMEs. If one is found, then the leading edge is measured over several successive frames and an elongation-time plot constructed. A minimum of three data points, i.e., over 3-4 orbits or about 6 hours, are necessary for such a plot. Using the solar source location and onset time of the CME from, e.g., SOHO observations, and assuming radial propagation, a distance-time relation is calculated and extrapolated to the 1 AU distance. As shown by Webb et al., the storm onset time is then expected to be about 3 hours after this 1 AU arrival time (AT). The prediction program is updated as more SMEI data become available. Currently when an appropriate solar event occurs, AFWA routinely runs the HAFv2 model to make a forecast of the shock and ejecta arrival times at Earth. SMEI data can be used to improve this prediction. The HAFv2 model can produce synthetic sky maps of predicted CME brightness for comparison with SMEI images. The forecaster uses SMEI imagery to observe and track the CME. The forecaster then measures the CME location and speed using the SMEI imagery and the HAFv2 synthetic sky maps. After comparing the SMEI and HAFv2 results, the forecaster can adjust a key input to HAFv2, such as the initial speed of the disturbance at the Sun or the mid-course speed. The forecaster then iteratively runs HAFv2 until the observed and forecast sky maps match. The final HAFv2 solution becomes the new forecast. When the CME/shock arrives at (or does not reach) Earth, the forecaster verifies the forecast and updates the forecast skill statistics. Eventually, we plan to develop a more automated version of this procedure.

Webb, D. F.; Johnston, J. C.; Fry, C. D.; Kuchar, T. A.

2008-12-01

240

Coronal Mass Ejection (CME) Activity of Low Mass M Stars as An Important Factor for The Habitability of Terrestrial Exoplanets. II. CME-Induced Ion Pick Up of Earth-like Exoplanets in Close-In Habitable Zones  

Microsoft Academic Search

Atmospheric erosion of CO2 -rich Earth-size exoplanets due to coronal mass ejection (CME)-induced ion pick up within close-in habitable zones of active M-type dwarf stars is investigated. Since M stars are active at the X-ray and extreme ultraviolet radiation (XUV) wave-lengths over long periods of time, we have applied a thermal balance model at various XUV flux input values for

Helmut Lammer; Herbert I. M. Lichtenegger; Yuri N. Kulikov; Jean-Mathias Grießmeier; N. Terada; Nikolai V. Erkaev; Helfried K. Biernat; Maxim L. Khodachenko; Ignasi Ribas; Thomas Penz; Franck Selsis

2007-01-01

241

Routine Vaginal Delivery  

MedlinePLUS

... Friendly Doctor Delivery by Cesarean Section Choosing a School Delivery: What About the Pain? Banking Cord Blood Study Finds Over 4,500 U.S. Children Hospitalized From Child Abuse in One Year, and 300 of Them Died ...

242

Magnetic Reconnection and the Deduced Properties of Plasma inside the CME/Flare Current Sheet  

NASA Astrophysics Data System (ADS)

In the present work, we display our results of studying and analyzing the observational data from UVCS and other remote sensing instruments for three CME/flare events that obviously developed a long current sheet during the eruptions. These results include the thickness of the current sheets, magnetic diffusivities and electrical conductivities (resistivities) of the plasma inside the current sheets. This is the first time that the electrical conductivity (resistivity) within magnetic reconnection region during the real eruptive processes has been deduced since the theory of magnetic reconnection was applied to the solar eruptions about 6 decades ago. The thickness of the current sheet developed during the January 8, 2002 event varies from 7 × 104 km to 2.2 × 105 km for altitudes between 2.5 R? and 5.5 R?, with the average thickness of 1.4× 105 km, and the speed of magnetic reconnection inflow near the current sheet is about 10 km s-1. These results suggest a magnetic diffusivity of the plasma inside the current sheet to be 0.7 × 1012 m2 s-1 (compared to the classical value for the quiet corona of 1 m2 s-1, and to the corresponding value for the "turbulent plasma" of 3.4× 106 m2 s-1). For the event occurring on November 18, 2003, the data from UVCS indicate that the upper limit of the current sheet thickness at altitude of 1.7 R? is about 2.8 × 104 km, and that the velocity of magnetic reconnection inflow near the current sheet ranges from 10.5 km s-1 to 106 km s-1. Combining these results yields a range of magnetic diffusivity from 1.4× 1011 m2 s-1 to 1.4× 1012 m2 s-1. During the event observed on March 23, 1998, the upper limit of the thickness of the current sheet in the wake of a CME is about 105 km according to data from UVCS. No data for the velocity of the magnetic reconnection near the current sheet in this event were obtained. Considering the fact that this event was more gradual than the other two cases, we assume the inflow speed in this event to be 5 km s-1. So, we obtain that the magnetic diffusivity of the plasma inside the current sheet has an upper limit of 2.5× 1011 m2 s-1. We notice that values of magnetic diffusivity deduced for three different events are within the range of magnitude.

Lin, J.; Li, J.; Forbes, T. G.; Ko, Y.; Raymond, J. C.; van Ballegooijen, A. A.

2005-05-01

243

Correlation Between CME Occurrence Rate and Current Helicity in the Global Magnetic Field of Solar Cycle 23  

NASA Astrophysics Data System (ADS)

We investigate the correlation between the occurrence rate of the monthly coronal mass ejection (CME) and the magnitude of the current helicity in global magnetic field on the photosphere of solar cycle 23. We used the technique introduced by Pevtsov and Latushko ( Astrophys. J. 528, 999, 2000) to retrieve the vector magnetic field from longitudinal full-disk magnetograms, but applied a different method to calculate the current helicity and focused on the evolution of the magnitude of current helicity over a full solar cycle. We found that there is a close relationship between the variation of the current helicity in the global magnetic field and that of the monthly CME occurrence rate. This provides further evidence to support that helicity is an important ingredient for solar eruptions.

Wang, Chuanyu; Zhang, Mei

2015-03-01

244

Elemental composition before, during and after the January 6, 1997, CME event measured by CELIAS/SOHO  

NASA Technical Reports Server (NTRS)

Using solar wind particle data from the charge, element and isotope analysis system (CELIAS) experiment on the SOHO mission, densities of the elements O, Ne, Mg, Si, S, Ca, and Fe are derived, and their abundance is analyzed before, during and after the 6 Janaury 1997 coronal mass ejection event (CME). In the interstream and coronal hole regions before and after this event, typical solar wind abundances for the elements investigated were found. However, during the passage of the coronal mass ejection and during the passage of the erupted filament, the elemental composition differed markedly from typical solar wind. For the passage of the CME and for the passage of the erupted filament, a mass-dependent enhancement of the elements was found, with a monotonic increase towards heavier elements. Si/O and Fe/O ratios of the order of one during these time periods were observed.

Wurz, P.; Ipavich, F. M.; Galvin, A. B.; Bochsler, P.; Aellig, M. R.; Kallenbach, R.; Hovestadt, D.; Gruenwaldt, H.; Hilchenbach, M.; Axford, W. I.; Balsiger, H.; Buergi, A.; Coplan, M. A.; Geiss, J.; Gliem, F.; Gloeckler, G.; Hefti, S.; Hsieh, K. C.; Klecker, B.; Lee, M. A.

1997-01-01

245

Articulating feedstock delivery device  

DOEpatents

A fully articulable feedstock delivery device that is designed to operate at pressure and temperature extremes. The device incorporates an articulating ball assembly which allows for more accurate delivery of the feedstock to a target location. The device is suitable for a variety of applications including, but not limited to, delivery of feedstock to a high-pressure reaction chamber or process zone.

Jordan, Kevin

2013-11-05

246

Tracking the Momentum Flux of a CME and Quantifying Its Influence on Geomagnetically Induced Currents at Earth  

NASA Technical Reports Server (NTRS)

We investigate a coronal mass ejection (CME) propagating toward Earth on 29 March 2011. This event is specifically chosen for its predominately northward directed magnetic field, so that the influence from the momentum flux onto Earth can be isolated. We focus our study on understanding how a small Earth-directed segment propagates. Mass images are created from the white-light cameras onboard STEREO which are also converted into mass height-time maps (mass J-maps). The mass tracks on these J-maps correspond to the sheath region between the CME and its associated shockfront as detected by in situ measurements at L1. A time series of mass measurements from the STEREOCOR-2A instrument is made along the Earth propagation direction. Qualitatively, this mass time series shows a remarkable resemblance to the L1 in situ density series. The in situ measurements are used as inputs into a three-dimensional (3-D) magnetospheric space weather simulation from the Community Coordinated Modeling Center. These simulations display a sudden compression of the magnetosphere from the large momentum flux at the leading edge of the CME, and predictions are made for the time derivative of the magnetic field (dBdt) on the ground. The predicted dBdt values were then compared with the observations from specific equatorially located ground stations and showed notable similarity. This study of the momentum of a CME from the Sun down to its influence on magnetic ground stations on Earth is presented as a preliminary proof of concept, such that future attempts may try to use remote sensing to create density and velocity time series as inputs to magnetospheric simulations.

Savani, N. P.; Vourlidas, A.; Pulkkinen, A.; Nieves-Chinchilla, T.; Lavraud, B.; Owens, M. J.

2013-01-01

247

Does an offer for a free on-line continuing medical education (CME) activity increase physician survey response rate? A randomized trial  

PubMed Central

Background Achieving a high response rate in a physician survey is challenging. Monetary incentives increase response rates but obviously add cost to a survey project. We wondered whether an offer of a free continuing medical education (CME) activity would be effective in improving survey response rate. Results As part of a survey of a national sample of physicians, we randomized half to an offer for a free on-line CME activity upon completion of a web-based survey and the other half to no such offer. We compared response rates between the groups. A total of 1214 out of 8477 potentially eligible physicians responded to our survey, for an overall response rate of 14.3%. The response rate among the control group (no offer of CME credit) was 16.6%, while among those offered the CME opportunity, the response rate was 12.0% (p < 0.0001). Conclusions An offer for a free on-line CME activity did not improve physician survey response rate. On the contrary, the offer for a free CME activity actually appeared to worsen the response rate. PMID:22397624

2012-01-01

248

On the Statistical Relationship between CME Speed and Soft X-ray Flux and Fluence of the Associated Flare  

E-print Network

Both observation and theory reveal a close relationship between the kinematics of coronal mass ejections (CMEs) and the thermal energy release traced by the related soft X-ray (SXR) emission. The major problem of empirical studies of this relationship is the distortion of the CME speed by the projection effect in the coronagraphic measurements. We present a re-assessment of the statistical relationship between CME velocities and SXR parameters, using the SOHO/LASCO catalog and GOES whole Sun observations during the period 1996 to 2008. 49 events were identified where CMEs originated near the limb, at central meridian distances between 70$^\\circ$ and 85$^\\circ$, and had a reliably identified SXR burst, the parameters of which - peak flux and fluence - could be determined with some confidence. We find similar correlations between the logarithms of CME speed and of SXR peak flux and fluence as several earlier studies, with correlation coefficients of 0.48 and 0.58, respectively. Correlations are slightly improve...

Salas-Matamoros, Carolina

2015-01-01

249

EUV observations of CME-associated eruptive phenomena with the CORONAS-F/SPIRIT telescope/spectroheliograph  

NASA Astrophysics Data System (ADS)

A multi-channel SPIRIT telescope/spectroheliograph aboard the CORONAS-F satellite operating in soft X-ray and EUV ranges ( T ˜ 0.05-15 MK) is an effective instrument for complex studies of CME-associated phenomena such as eruptive filaments, dimmings, coronal waves, posteruptive arcades, etc. In particular, SRIRIT observations of high-temperature (T = 5-15 MK) plasma structures in the MgXII 8.42 Å line show specific pre-CME sigmoid magnetic field configurations. Eruptions of filaments (prominences) and dimmings in a CME process are seen with a high contrast in the coronal 175 Å band (FeIX-XI) and the transition-region 304 Å (HeII) images. Our results are illustrated by several powerful eruptive events of the current solar cycle. We compare SPIRIT data with observations at other spaceborne and ground-based instruments (SOHO/EIT, Yohkoh/SXT, and H ? images, etc.)

Slemzin, V. A.; Grechnev, V. V.; Zhitnik, I. A.; Kuzin, S. V.; Chertok, I. M.; Bogachev, S. A.; Ignatiev, A. P.; Pertsov, A. A.; Lisin, D. V.

250

Comprehensive chronic pain management: improving physical and psychological function (CME multimedia activity).  

PubMed

As shown in this CME online activity (www.cmeaccess.com/AJM/ChronicPain02), chronic, non-cancer pain can arise from a variety of etiologies and can be broadly classified based on its underlying mechanism as nociceptive, inflammatory, neuropathic, or central, with some patients having pain arising from a combination of mechanisms. Chronic pain assessment and treatment involves evaluating not only its biological aspects, but also psychological and sociocultural factors. Beyond neural mechanisms, a patient's perception of chronic pain can be influenced by comorbid mood disorders, such as depression and anxiety; cognitive and affective traits, such as catastrophizing and fear-avoidance; environmental stressors, family relationships, social support, and cultural beliefs. Based on this biopsychosocial model, a multidisciplinary approach to management incorporates pharmacotherapy (opioid, nonopioid, and centrally-acting analgesics, and pain adjuvant medications) with nonpharmacologic physical rehabilitation and psychological and behavioral therapies to address the multifactorial causes of chronic pain, which in turn leads to improvement of physical and psychological function. PMID:22624694

McCarberg, Bill H; Stanos, Steven; Williams, David A

2012-06-01

251

Development of a full ice-cream cone model for halo CME structures  

NASA Astrophysics Data System (ADS)

The determination of three dimensional parameters (e.g., radial speed, angular width, source location) of Coronal Mass Ejections (CMEs) is very important for space weather forecast. To estimate these parameters, several cone models based on a flat cone or a shallow ice-cream cone with spherical front have been suggested. In this study, we investigate which cone model is proper for halo CME morphology using 33 CMEs which are identified as halo CMEs by one spacecraft (SOHO or STEREO-A or B) and as limb CMEs by the other ones. From geometrical parameters of these CMEs such as their front curvature, we find that near full ice-cream cone CMEs (28 events) are dominant over shallow ice-cream cone CMEs (5 events). So we develop a new full ice-cream cone model by assuming that a full ice-cream cone consists of many flat cones with different heights and angular widths. This model is carried out by the following steps: (1) construct a cone for given height and angular width, (2) project the cone onto the sky plane, (3) select points comprising the outer boundary, (4) minimize the difference between the estimated projection points with the observed ones. We apply this model to several halo CMEs and compare the results with those from other methods such as a Graduated Cylindrical Shell model and a geometrical triangulation method.

Na, Hyeonock; Moon, Yong-Jae

2015-04-01

252

Kinetic Approaches to Shear-Driven Magnetic Reconnection for Multi-Scale Modeling of CME Initiation  

NASA Astrophysics Data System (ADS)

In the standard model for coronal mass ejections (CME) and/or solar flares, the free energy for the event resides in the strongly sheared magnetic field of a filament channel. The pre-eruption force balance, consisting of an upward force due to the magnetic pressure of the sheared field balanced by a downward tension due to overlying un-sheared field, is widely believed to be disrupted by magnetic reconnection. Therefore, understanding initiation of solar explosive phenomena requires a true multi-scale model of reconnection onset driven by the buildup of magnetic shear. While the application of magnetic-field shear is a trivial matter in MHD simulations, it is a significant challenge in a PIC code. The driver must be implemented in a self-consistent manner and with boundary conditions that avoid the generation of waves that destroy the applied shear. In this work, we describe drivers for 2.5D, aperiodic, PIC systems and discuss the implementation of driver-consistent boundary conditions that allow a net electric current to flow through the walls. Preliminary tests of these boundaries with a MHD equilibrium are shown. This work was supported, in part, by the NASA Living With a Star TR&T Program.

Black, C.; Antiochos, S. K.; DeVore, C.; Germaschewski, K.; Karpen, J. T.

2013-12-01

253

CME Mass Estimates via EVE Coronal Dimmings for X-class Flares  

NASA Astrophysics Data System (ADS)

The EVE instrument on SDO detects post-flare dimmings, mainly in the spectral regions of Fe IX-XII in its MEGS-A range, which is available for most of the 29 X-class flares that have occurred between SDO launch and the end of April 2014. Based upon earlier X-ray observations we interpret these dimmings as the result of CME mass ejection from the low corona. We estimate the masses involved in these dimmings by deriving a best pre-event temperature and emission measure in the dimmed region from EVE, and a source volume from AIA images. The dimming for SOL2011-02-15, the first of these events, "peaked"at -3.4% in Fe IX in terms of the pre-event emission from the whole Sun, with smaller relative depletions in higher ionization states of Fe. The "maximum" occurred more than one hour after GOES peak. The dimming signature is generally cleanly measurable in the EVE/MEGS-A spectral samples at10 s cadence, with the dominant source of uncertainty stemming from the "sun-as-a-star" integrations; for example flare-related excess emission at a given wavelength tends to compensate for the dimming,and in this sense the mass estimate must be considered a lower limit. We address these uncertainties for the solar case by appealing to the AIA images, but for analogous processes in stellar flares one would not have this luxury.

Hudson, Hugh S.; Hannah, Iain; Schrijver, Karel

2014-06-01

254

Numerical experiments of magnetic reconnection in the solar flare and CME current sheet  

NASA Astrophysics Data System (ADS)

Magnetic reconnection plays a critical role in the energy conversion in the solar eruption. This paper performs a set of MHD experiments for the magnetic reconnection process in a current sheet formed in a disrupting magnetic configuration. The eruption results from the loss of equilibrium in the magnetic configuration that includes a current-carrying flux rope, which is used to model the filament floating in the corona. In order to study the fine structure and micro process inside the current sheet (CS), the mesh refinement technology is used to depress the numerical diffusion. A uniform physical diffusion is applied and results in a Lundquist number S=10^4 in the vicinity of CS. Because of the advantage of the foregoing setting, some features appear with high resolution, including plasmoids due to the tearing mode and the plasmoid instabilities, turbulence regions, and the slow mode shocks. Inside CS, magnetic reconnection goes through the Sweet-Parker and the fractal fashions, and eventually, it displays a time-dependent Petschek pattern. Our results seem to support the concept of fractal reconnection suggested by Shibata et al. (1995) and Shibata & Tanuma (2001). And our results suggest that the CS evolves through a Sweet-Parker reconnection prior to the fast reconnection stage. For the first time, the detailed features and/or fine structures inside the CME/flare CS in the eruption were investigated in this work.

Mei, Zhixing; Lin, Jun; Shen, Chengcai

2012-07-01

255

Trauma-Informed Medical Care: A CME Communication Training for Primary Care Providers  

PubMed Central

BACKGROUND AND OBJECTIVES: Trauma exposure predicts mental disorders, medical morbidity, and healthcare costs. Yet trauma-related impacts have not received sufficient attention in primary care provider (PCP) training programs. This study adapted a theory-based approach to working with trauma survivors, Risking Connection, into a 6-hour CME course, Trauma-Informed Medical Care (TI-Med), and evaluated its efficacy. METHODS: We randomized PCPs to training or wait-list (delay) conditions; waitlist groups were trained after reassessment. The primary outcome assessing newly acquired skills was a patient-centeredness score derived from Roter Interactional Analysis System ratings of 90 taped visits between PCPs and standardized patients (SPs). PCPs were Family Medicine residents (n=17) and community physicians (n=13; 83% Family Medicine specialty), from four sites in the Washington DC metropolitan area. RESULTS: Immediately trained PCPs trended toward a larger increase in patient-centeredness than did the delayed PCPs (p < .09), with a moderate effect size (.66). The combined trained PCP groups showed a significant increase in patient-centeredness pre to post training, p < .01, Cohen’s D = .61. CONCLUSIONS: This is a promising approach to supporting relationship-based trauma-informed care among PCPs to help promote better patient health and higher compliance with medical treatment plans. PMID:25646872

Green, Bonnie L.; Saunders, Pamela A.; Power, Elizabeth; Dass-Brailsford, Priscilla; Schelbert, Kavitha Bhat; Giller, Esther; Wissow, Larry; Hurtado-de-Mendoza, Alejandra; Mete, Mihriye

2014-01-01

256

Modeling magnetohydrodynamics and non-equilibrium SoHO/UVCS line emission of CME shocks  

NASA Astrophysics Data System (ADS)

The Coronal Mass Ejections are plasma clouds expelled from the Sun into the interplanetary medium. We study the propagation of shock waves in the solar corona generated during Coronal Mass Ejections by means of a numerical multi-dimensional MHD model. The model describes the MHD evolution of a compressible plasma in an ambient magnetic field including tensor thermal conduction, radiative losses as main physical effects. We use the MHD version of the FLASH parallel hydrodynamic code with adaptive mesh refinement, originally developed at the University of Chicago USA). The code is highly modular and made efficiently parallel with the Message Passing Interface library. We analyze the diagnostic signatures of shock fronts generated by supersonic CME fragments detectable with the UltraViolet Coronagraphic Spectrometer on board the SoHO mission. To this aim we perform 3D MHD simulations of the shock propagation for the time it takes to cross the UVCS slit positioned at a distance of a few solar radii from the solar surface. In the presence of highly effective thermal conduction the simulation takes 200000 time steps to cover 1000 s of evolution. Considering a 3-D domain of 256x256x512 grid cells this kind of simulations requires thousands of hours of computer time and therefore high performance computing (HPC) systems. The simulations were run on the CINECA IBM/SP5 HPC cluster within the INAF/CINECA agreement. We show simulation results and some implications for UVCS observations.

Pagano, P.; Raymond, J. C.; Reale, F.

257

Post Alpbach-summerschool project: CARRINGTON MISSION FOR CME DETECTION TO IMPROVE SPACE WEATHER FORECAST  

NASA Astrophysics Data System (ADS)

The effects of solar activity, especially Coronal Mass Ejections (CMEs), on Earth- and satellite-based systems are well-known and can cause major damage to space-dependent infrastructure. The main problem in current space weather forecasting is the inability to determine necessary forecast parameters of CMEs and Corotating Interaction Regions (CIRs) early enough to react. We present the design for a novel space mission consisting of two spacecraft that is aimed to perform stereoscopic measurements on Earth-directed CMEs and in-situ measurements of CIRs. The magnetic field orientation and structure of CMEs will be measured close to the Sun, using spectro-polarimetry. Geoeffectiveness will be derived by remote sensing the CMEs magnetic field at 0.64AU from the Sun, determining the full magnetic field vector of a CME. This will be achieved by the novel concept of measuring its polarising effects on spacecraft to spacecraft laser beams based upon heterodyne interferometry. Overall structure and trajectory of CMEs will also be monitored by heliospheric imagers and in-situ plasma instruments. To achieve the mission objectives, the orbit is heliocentric at 1AU with a separation angle from the Earth of ±50°. The operational mission lifetime is 6 years with a proposed 6 year extension. If implemented, Carrington will serve as a forecast system which will significantly improve the minimum forecast time for the fastest CMEs with 2000 km/s, from 13 minutes based on current L1 satellites, to around 3 hours.

Scheucher, Markus; Urbar, Jaroslav; Musset, Sophie; Andersson, Viktor; Gini, Francesco; Gorski, Jedrzej; Jüstel, Peter; Kiefer, René; Lee, Arrow; Meskers, Arjan; Miles, Oscar; Perakis, Nikolas; Rußwurm, Michael; Scully, Stephen; Seifert, Bernhard; Sorba, Arianna

2014-05-01

258

Commercial Document Delivery Services "Challenged" as EBSCO Drops Service.  

ERIC Educational Resources Information Center

Discusses the EBSCO decision to stop its traditional commercial document delivery business. High prices for copyright clearance, government subsidized services, electronic formats available on the Internet, Web-based services, and consortium-based licensing activities are discussed as influencing the market for document delivery. (LRW)

Machovec, George S.

1998-01-01

259

Biodegradable hybrid polymeric membranes for ocular drug delivery  

Microsoft Academic Search

Ophthalmic delivery systems such as ocular inserts are useful strategies to improve the ocular bioavailability of topically administered drugs. In the present study polyvinyl alcohol and sodium carboxymethylcellulose based ocular inserts were prepared by solution casting for sustained drug delivery of ciprofloxacin for treatment of topical infections. The polymers were esterified and the formation of ester bonds was confirmed by

Dharmendra Jain; Edmund Carvalho; R. Banerjee

2010-01-01

260

Intracochlear Drug Delivery Systems  

PubMed Central

Introduction Advances in molecular biology and in the basic understanding of the mechanisms associated with sensorineural hearing loss and other diseases of the inner ear, are paving the way towards new approaches for treatments for millions of patients. However, the cochlea is a particularly challenging target for drug therapy, and new technologies will be required to provide safe and efficacious delivery of these compounds. Emerging delivery systems based on microfluidic technologies are showing promise as a means for direct intracochlear delivery. Ultimately, these systems may serve as a means for extended delivery of regenerative compounds to restore hearing in patients suffering from a host of auditory diseases. Areas covered in this review Recent progress in the development of drug delivery systems capable of direct intracochlear delivery is reviewed, including passive systems such as osmotic pumps, active microfluidic devices, and systems combined with currently available devices such as cochlear implants. The aim of this article is to provide a concise review of intracochlear drug delivery systems currently under development, and ultimately capable of being combined with emerging therapeutic compounds for the treatment of inner ear diseases. Expert Opinion Safe and efficacious treatment of auditory diseases will require the development of microscale delivery devices, capable of extended operation and direct application to the inner ear. These advances will require miniaturization and integration of multiple functions, including drug storage, delivery, power management and sensing, ultimately enabling closed-loop control and timed-sequence delivery devices for treatment of these diseases. PMID:21615213

Borenstein, Jeffrey T.

2011-01-01

261

Power Delivery of the Future  

E-print Network

This paper is written to provide an insight into the physics and engineering that go into power delivery of the future. Topics covered are Fault Current Limiters (FCL) including Superconducting FCL and Emission Limited FCL; Lightning and Restoration Preparedness; Compressed-Gas-Insulated Delivery; Evaporative Cooling Delivery; Advanced Delivery Technologies Requiring Big Breakthroughs such as Conducting Polymers, Electron-Beam Delivery, Microwave Delivery, and Laser-Beam Delivery.

Mario Rabinowitz

2003-04-26

262

An Asynchronous Augmentation to Traditional Course Delivery.  

ERIC Educational Resources Information Center

Asynchronous augmentation facilitates distributed learning, which relies heavily on technology and self-learning. This paper reports the results of delivering a real estate principles course using an asynchronous course delivery format. It highlights one of many ways to enhance learning using technology, and it provides information concerning how…

Wolverton, Marvin L.; Wolverton, Mimi

263

One Quiz File, Several Modes of Delivery  

ERIC Educational Resources Information Center

This report offers online course designers, particularly those keen on using Moodle CMSs, a means of diversifying accessibility to their educational materials via multiple modes of delivery that do not require the creation of numerous files and formats for just one activity. The author has made contributions to the development of an open source…

Herbert, John C.

2012-01-01

264

APPLICATIONS OF ELECTROSPINNING TECHNIQUE IN DRUG DELIVERY  

Microsoft Academic Search

Electrospinning has proven to be a simple, versatile, and useful technique for fabricating nanofibers from a rich variety of functional materials. In the past few years, we have witnessed tremendous research progress in understanding electrospinning mechanisms and their applications in controlled drug releasing and delivery. In this review, a brief description of the electrospinning process and fiber formation mechanisms is

Bochu Wang; Yazhou Wang; Tieying Yin; Qingsong Yu

2010-01-01

265

Use of Yohkoh SXT in Measuring the Net Current and CME Productivity of Active Regions  

NASA Astrophysics Data System (ADS)

In our investigation of the correlation of global nonpotentiality of active regions to their CME productivity (Falconer, D. A. 2001, JGR, in press, and Falconer, Moore, & Gary, 2000, EOS 82, 20 S323), we use Yohkoh SXT images for two purposes. The first use is to help resolve the 180o ambiguity in the direction of the observed transverse magnetic field. Resolution of the 180o ambiguity is important, since the net current, one of our measures of global nonpotentiality, is derived from integrating the dot product of the transverse field around a contour (IN = int BTcdot dl). The ambiguity results from the observed transverse field being determined from the linear polarization, which gives the plane of the direction, but leaves a 180o ambiguity. Automated methods to resolve the ambiguity ranging from the simple acute angle rule (Falconer, D. A. 2001) to the more sophisticated annealing method (Metcalf T. R. 1994). For many active regions, especially ones that are nearly potential these methods work well. But for very nonpotential active regions where the shear angle (the angle between the observed and potential transverse field) is near 90o throughout large swaths along the main neutral line, both methods can resolve the ambiguity incorrectly for long segments of the neutral line. By determining from coronal images, such as those from Yohkoh/SXT, the sense of shear along the main neutral line in the active region, these cases can be identified and corrected by a modification of the acute angle rule described here. The second use of Yohkoh/SXT in this study is to check for the cusped coronal arcades of long-duration eruptive flares. This signature is an excellent proxy for CMEs, and was used by Canfield, Hudson, and McKenzie (1999 GRL V26, 6, 627-630). This work is funded by NSF through the Space Weather Program and by NASA through the Solar Physics Supporting Research and Technology Program.

Falconer, D. A.; Moore, R. L.; Gary, G. A.

2002-01-01

266

Using email reminders to engage physicians in an Internet-based CME intervention  

PubMed Central

Background Engaging practicing physicians in educational strategies that reinforce guideline adoption and improve the quality of healthcare may be difficult. Push technologies such as email offer new opportunities to engage physicians in online educational reinforcing strategies. The objectives are to investigate 1) the effectiveness of email announcements in engaging recruited community-based primary care physicians in an online guideline reinforcement strategy designed to promote Chlamydia screening, 2) the characteristics of physicians who respond to email announcements, as well as 3) how quickly and when they respond to email announcements. Methods Over a 45-week period, 445 recruited physicians received up to 33 email contacts announcing and reminding them of an online women's health guideline reinforcing CME activity. Participation was defined as physician log-on at least once to the website. Data were analyzed to determine participation, to compare characteristics of participants with recruited physicians who did not participate, and to determine at what point and when participants logged on. Results Of 445 recruited physicians with accurate email addresses, 47.2% logged on and completed at least one module. There were no significant differences by age, race, or specialty between participants and non-participants. Female physicians, US medical graduates and MDs had higher participation rates than male physicians, international medical graduates and DOs. Physicians with higher baseline screening rates were significantly more likely to log on to the course. The first 10 emails were the most effective in engaging community-based physicians to complete the intervention. Physicians were more likely to log on in the afternoon and evening and on Monday or Thursday. Conclusions Email course reminders may enhance recruitment of physicians to interventions designed to reinforce guideline adoption; physicians' response to email reminders may vary by gender, degree, and country of medical training. Repetition of email communications contributes to physician online participation. PMID:15453911

Abdolrasulnia, Maziar; Collins, Blanche C; Casebeer, Linda; Wall, Terry; Spettell, Claire; Ray, Midge N; Weissman, Norman W; Allison, Jeroan J

2004-01-01

267

43 CFR Appendix II to Part 11 - Format for Data Inputs and Modifications to the NRDAM/CME  

Code of Federal Regulations, 2012 CFR

...environment stated in hours. Time Year, month, day, and hour when the identified substance first entered...one set of data on prevailing wind conditions for each day of the 30-day period beginning 24 hours before the identified...

2012-10-01

268

43 CFR Appendix II to Part 11 - Format for Data Inputs and Modifications to the NRDAM/CME  

Code of Federal Regulations, 2010 CFR

...environment stated in hours. Time Year, month, day, and hour when the identified substance first entered...one set of data on prevailing wind conditions for each day of the 30-day period beginning 24 hours before the identified...

2010-10-01

269

43 CFR Appendix II to Part 11 - Format for Data Inputs and Modifications to the NRDAM/CME  

Code of Federal Regulations, 2011 CFR

...environment stated in hours. Time Year, month, day, and hour when the identified substance first entered...one set of data on prevailing wind conditions for each day of the 30-day period beginning 24 hours before the identified...

2011-10-01

270

43 CFR Appendix II to Part 11 - Format for Data Inputs and Modifications to the NRDAM/CME  

Code of Federal Regulations, 2014 CFR

...environment stated in hours. Time Year, month, day, and hour when the identified substance first entered...one set of data on prevailing wind conditions for each day of the 30-day period beginning 24 hours before the identified...

2014-10-01

271

43 CFR Appendix II to Part 11 - Format for Data Inputs and Modifications to the NRDAM/CME  

Code of Federal Regulations, 2013 CFR

...environment stated in hours. Time Year, month, day, and hour when the identified substance first entered...one set of data on prevailing wind conditions for each day of the 30-day period beginning 24 hours before the identified...

2013-10-01

272

The First Ground Level Enhancement Event of Solar Cycle 24: Direct Observation of Shock Formation and Particle Release Heights  

NASA Astrophysics Data System (ADS)

We report on the 2012 May 17 ground level enhancement (GLE) event, which is the first of its kind in solar cycle 24. This is the first GLE event to be fully observed close to the surface by the Solar Terrestrial Relations Observatory (STEREO) mission. We determine the coronal mass ejection (CME) height at the start of the associated metric type II radio burst (i.e., shock formation height) as 1.38 Rs (from the Sun center). The CME height at the time of GLE particle release was directly measured from a STEREO image as 2.32 Rs, which agrees well with the estimation from CME kinematics. These heights are consistent with those obtained for cycle-23 GLEs using back-extrapolation. By contrasting the 2012 May 17 GLE with six other non-GLE eruptions from well-connected regions with similar or larger flare sizes and CME speeds, we find that the latitudinal distance from the ecliptic is rather large for the non-GLE events due to a combination of non-radial CME motion and unfavorable solar B0 angle, making the connectivity to Earth poorer. We also find that the coronal environment may play a role in deciding the shock strength.

Gopalswamy, N.; Xie, H.; Akiyama, S.; Yashiro, S.; Usoskin, I. G.; Davila, J. M.

2013-03-01

273

Nonviral Vectors for Gene Delivery  

NASA Astrophysics Data System (ADS)

The development of nonviral vectors for safe and efficient gene delivery has been gaining considerable attention recently. An ideal nonviral vector must protect the gene against degradation by nuclease in the extracellular matrix, internalize the plasma membrane, escape from the endosomal compartment, unpackage the gene at some point and have no detrimental effects. In comparison to viruses, nonviral vectors are relatively easy to synthesize, less immunogenic, low in cost, and have no limitation in the size of a gene that can be delivered. Significant progress has been made in the basic science and applications of various nonviral gene delivery vectors; however, the majority of nonviral approaches are still inefficient and often toxic. To this end, two nonviral gene delivery systems using either biodegradable poly(D,L-lactide- co-glycolide) (PLG) nanoparticles or cell penetrating peptide (CPP) complexes have been designed and studied using A549 human lung epithelial cells. PLG nanoparticles were optimized for gene delivery by varying particle surface chemistry using different coating materials that adsorb to the particle surface during formation. A variety of cationic coating materials were studied and compared to more conventional surfactants used for PLG nanoparticle fabrication. Nanoparticles (˜200 nm) efficiently encapsulated plasmids encoding for luciferase (80-90%) and slowly released the same for two weeks. After a delay, moderate levels of gene expression appeared at day 5 for certain positively charged PLG particles and gene expression was maintained for at least two weeks. In contrast, gene expression mediated by polyethyleneimine (PEI) ended at day 5. PLG particles were also significantly less cytotoxic than PEI suggesting the use of these vehicles for localized, sustained gene delivery to the pulmonary epithelium. On the other hand, a more simple method to synthesize 50-200 nm complexes capable of high transfection efficiency or high gene knockdown was also explored. Positively charged CPPs were complexed with pDNA or siRNA, which resulted in 'loose' (˜1 micron) particles. These were then condensed into small nanoparticles by using calcium, which formed "soft" crosslinks by interacting with both phosphates on nucleic acids and amines on CPPs. An optimal amount of CaCl2 produced stable, ˜100 nm complexes that exhibited higher transfection efficiency and gene silencing than PEI polyplexes. CPPs also displayed negligible cytotoxicity up to 5 mg/mL. Biophysical studies of the pDNA structure within complexes suggested that pDNA within CPP complexes (condensed with calcium) had similar structure, but enhanced thermal stability compared to PEI complexes. Thus, CPP complexes emerged as simple, attractive candidates for future studies on nonviral gene delivery in vivo.

Baoum, Abdulgader Ahmed

2011-12-01

274

Comparison of the CME-associated shock arrival times at the earth using the WSA-ENLIL model with three cone models  

NASA Astrophysics Data System (ADS)

We have made a comparison of CME-associated shock arrival times at the earth based on the WSA-ENLIL model with three cone models using 29 halo CMEs from 2001 to 2002. These halo CMEs have cone model parameters from Michalek et al. (2007) as well as their associated interplanetary (IP) shocks. For this study we consider three different cone models (an asymmetric cone model, an ice-cream cone model and an elliptical cone model) to determine CME cone parameters (radial velocity, angular width and source location), which are used for input parameters of the WSA-ENLIL model. The mean absolute error (MAE) of the arrival times for the elliptical cone model is 10 hours, which is about 2 hours smaller than those of the other models. However, this value is still larger than that (8.7 hours) of an empirical model by Kim et al. (2007). We are investigating several possibilities on relatively large errors of the WSA-ENLIL cone model, which may be caused by CME-CME interaction, background solar wind speed, and/or CME density enhancement.

Jang, S.; Moon, Y.; Na, H.

2012-12-01

275

Statistical relationship between CME speed and soft X-ray flux and fluence of the associated flare during solar cycle 23  

NASA Astrophysics Data System (ADS)

We present a study of the statistical relationship between CME velocities reported in the SOHO/LASCO catalogue and soft X-Ray (SXR) measurements from the GOES satellites during the period 1996-2008, to explore the possible correlation between CME speed and parameters of the associated X-ray burst, peak flux and start-to-peak fluence. In order to minimize blurring by projection effects, we focused on CMEs originating near the solar limbs. The flare association was inferred from the backward extrapolation of the height-time trajectory of the CME, and was carefully checked for each event. For the resulting sample of 54 events we found similar positive correlations between the CME speed on the one hand, the SXR peak flux (r=0.50) and fluence (r=0.54) on the other. As a consistency check we compare the CME speeds inferred from SXR bursts with measurements by the STEREO mission for CMEs observed while the two spacecraft were near an angle of 90 degrees with the Sun-Earth line and we found that the calculated speeds are close to the measured value by the STEREO satellites. Furthermore we explore the usefulness of the method for estimating the ICME travel time to the Earth.

Salas Matamoros, Carolina; Klein, Karl-Ludwig

276

CME-associated dimmings on the Sun observed with the EUV SPIRIT telescope on the CORONAS-F spacecraft  

NASA Astrophysics Data System (ADS)

A space solar observatory CORONAS-F was launched in August 2001. The SPectrographIc X-Ray Imaging Telescope (SPIRIT) aboard CORONAS-F observes the Sun in several bands in EUV to soft X-rays, in particular, in EUV 175, 284 and 304 Å lines. Based on the SPIRIT observations in these lines, we have analyzed large-scale manifestations of halo-type coronal mass ejections (CMEs). The objects of our particular interest are dimmings living several hours. Our method involves an analysis of fixed difference images formed in two steps. First, we compensate the solar rotation using 3D 'derotation' of all heliograms to the same time, usually to the time of the base frame observed before the event. Then this frame is subtracted from all subsequent frames. Analysis of SPIRIT images using this technique allowed us to find some interesting features of eruptive events. In particular, in the 4 November 2001 event that was not observed with a similar EUV telescope SOHO/EIT, difference SPIRIT heliograms revealed two relatively compact dimmings adjoining to the eruptive center and several narrow channelled dimmings stretching to remote active regions. Development of one compact dimming observed in the transition region line 304 Å has a noticeable delay with respect to the coronal lines. During powerful eruptive events of October-November 2003, SPIRIT heliograms, in contrast to EIT images, were neither saturated by extremely intense flare emission, nor affected by very strong particle fluxes due to the low orbit of the spacecraft inside the Earth's magnetosphere. In the late phase of the 18 November 2003 event, SPIRIT 304 Å difference images display a propagating dimming associated perhaps with a CME disconnection from coronal structures that essentially supplements the picture of CME-initiated disturbances observed with EIT. Our analysis confirms that global magnetic structures above a considerable part of the solar disk can be involved in a CME process. The spatial coincidence of the main dimmings in the diverse-temperature lines suggests their origin due to plasma evacuation from partly or completely opened magnetic structures in the transition region and corona. For some dimmings whose appearance is dissimilar in different lines, CME-associated variations of the plasma temperature can play a role as well.

Kuzin, S.; Chertok, I.; Grechnev, V.; Slemzin, V.; Bugaenko, O.; Zhitnik, I.; Ignat'ev, A.; Pertsov, A.

277

FUEL DELIVERY TEMPERATURE STUDY  

E-print Network

Elkins ­ California State Water Resources Control Board Kurt Floren ­ Los Angeles County AgriculturalCALIFORNIA ENERGY COMMISSION FUEL DELIVERY TEMPERATURE STUDY COMMISSIONREPORT March 2009 CEC-600 and Nicholas Janusch, 2009. Fuel Delivery Temperature Study, California Energy Commission. CEC-600-2009-002-CMF

278

Real-Time CME Forecasting Using HMI Active-Region Magnetograms and Flare History  

NASA Technical Reports Server (NTRS)

We have recently developed a method of predicting an active region s probability of producing a CME, an X-class Flare, an M-class Flare, or a Solar Energetic Particle Event from a free-energy proxy measured from SOHO/MDI line-of-sight magnetograms. This year we have added three major improvements to our forecast tool: 1) Transition from MDI magnetogram to SDO/HMI magnetogram allowing us near-real-time forecasts, 2) Automation of acquisition and measurement of HMI magnetograms giving us near-real-time forecasts (no older than 2 hours), and 3) Determination of how to improve forecast by using the active region s previous flare history in combination with its free-energy proxy. HMI was turned on in May 2010 and MDI was turned off in April 2011. Using the overlap period, we have calibrated HMI to yield what MDI would measure. This is important since the value of the free-energy proxy used for our forecast is resolution dependent, and the forecasts are made from results of a 1996-2004 database of MDI observations. With near-real-time magnetograms from HMI, near-real-time forecasts are now possible. We have augmented the code so that it continually acquires and measures new magnetograms as they become available online, and updates the whole-sun forecast from the coming day. The next planned improvement is to use an active region s previous flare history, in conjunction with its free-energy proxy, to forecast the active region s event rate. It has long been known that active regions that have produced flares in the past are likely to produce flares in the future, and that active regions that are nonpotential (have large free-energy) are more likely to produce flares in the future. This year we have determined that persistence of flaring is not just a reflection of an active region s free energy. In other words, after controlling for free energy, we have found that active regions that have flared recently are more likely to flare in the future.

Falconer, David; Moore, Ron; Barghouty, Abdulnasser F.; Khazanov, Igor

2011-01-01

279

A Parametric Study of Erupting Flux Rope Rotation: Modeling the 'Cartwheel CME' on 9 April 2008  

NASA Technical Reports Server (NTRS)

The rotation of erupting filaments in the solar corona is addressed through a parametric simulation study of unstable, rotating flux ropes in bipolar force-free initial equilibrium. The Lorentz force due to the external shear-field component and the relaxation of tension in the twisted field are the major contributors to the rotation in this model, while reconnection with the ambient field is of minor importance, due to the field's simple structure. In the low-beta corona, the rotation is not guided by the changing orientation of the vertical field component's polarity inversion line with height. The model yields strong initial rotations which saturate in the corona and differ qualitatively from the profile of rotation vs. height obtained in a recent simulation of an eruption without preexisting flux rope. Both major mechanisms writhe the flux rope axis, converting part of the initial twist helicity, and produce rotation profiles which, to a large part, are very similar within a range of shear-twist combinations. A difference lies in the tendency of twist-driven rotation to saturate at lower heights than shear-driven rotation. For parameters characteristic of the source regions of erupting filaments and coronal mass ejections, the shear field is found to be the dominant origin of rotations in the corona and to be required if the rotation reaches angles of order 90 degrees and higher; it dominates even if the twist exceeds the threshold of the helical kink instability. The contributions by shear and twist to the total rotation can be disentangled in the analysis of observations if the rotation and rise profiles are simultaneously compared with model calculations. The resulting twist estimate allows one to judge whether the helical kink instability occurred. This is demonstrated for the erupting prominence in the "Cartwheel CME" on 9 April 2008, which has shown a rotation of approximately 115 deg. up to a height of 1.5 Solar R above the photosphere. Out of a range of initial equilibria which include strongly kink-unstable (Phi = 5 pi), weakly kink-unstable (Phi = 3.5 pi), and kink-stable (Phi = 2.5 pi) configurations, only the evolution of the weakly kink-unstable flux rope matches the observations in their entirety.

Kliem, B.; Toeroek, T.; Thompson, W. T.

2012-01-01

280

Use of Yohkoh SXT in Measuring the Net Current and CME Productivity of Active Regions  

NASA Technical Reports Server (NTRS)

In our investigation of the correlation of global nonpotentiality of active regions to their CME productivity (Falconer, D.A. 2001, JGR, in press, and Falconer, Moore, & Gary, 2000, EOS 82, 20 S323), we use Yohkoh SXT images for two purposes. The first use is to help resolve the 180 degree ambiguity in the direction of the observed transverse magnetic field. Resolution of the 180 degree ambiguity is important, since the net current, one of our measures of global nonpotentiality, is derived from integrating the dot product of the transverse field around a contour (I(sub N)=(integral)BT(raised dot)dl). The ambiguity results from the observed transverse field being determined from the linear polarization, which gives the plane of the direction, but leaves a 180 degrees ambiguity. Automated methods to resolve the ambiguity ranging from the simple acute angle rule (Falconer, D.A. 2001) to the more sophisticated annealing method (Metcalf T.R. 1994). For many active regions, especially ones that are nearly potential these methods work well. But for very nonpotential active regions where the shear angle (the angle between the observed and potential transverse field) is near 90 degrees throughout large swaths along the main neutral line, both methods can resolve the ambiguity incorrectly for long segments of the neutral line. By determining from coronal images, such as those from Yohkoh/SXT, the sense of shear along the main neutral line in the active region, these cases can be identified and corrected by a modification of the acute angle rule described here. The second use of Yohkoh/SXT in this study is to check for the cusped coronal arcades of long-duration eruptive flares. This signature is an excellent proxy for CMEs, and was used by Canfield, Hudson, and McKenzie (1999 GRL V26, 6, 627-630). This work is funded by NSF through the Space Weather Program and by NASA through the Solar Physics Supporting Research and Technology Program.

Falconer, D. A.; Moore, R. L.; Gary, G. A.; Six, N. Frank (Technical Monitor)

2001-01-01

281

Using SOHO to Understand CME-Producing Quiet-Region Filament Eruptions  

NASA Technical Reports Server (NTRS)

In recent years we have been studying solar eruptions in an attempt to determine their primary initiation mechanism. We have focused on events involving filaments, because motions of the filaments just prior to their violent eruption are indicative of changes in the entire magnetic field system involved in the eruption. When the pre-eruption filament resides in a quiet region, the motions leading up to eruption are slower than in similar eruptions in active regions due to the weaker magnetic field strength and correspondingly lower Alfven velocities. These early motions manifest themselves in a slow rise (a few km/s) of the filament, in some cases lasting several hours. After this the filament and associated magnetic structures erupt rapidly, accelerating to speeds of a few 10 kmh over a few minutes. Because of their slow evolution, quiet-region eruptions such as these can be effectively studied in EUV with SOHO/EIT, with its regular cadence of about 12 min. For several cases we have combined EIT images with SOHO/MDI magnetograms and data from other other instruments, and compared our observations with predictions from various eruption scenarios, in particular the "breakout" (Antiochos 1998), "tether cutting" (e.g., Moore et al. 2001), and MHD instability mechanisms. Here we present a representative example of a quiet-region eruption involving a filament ejection, that occurred on 2001 February 28 in a magnetically quadrupolar region and produced a halo CME in SOHO/LASCO images. In addition to EIT and MDI, we analyzed spectral data from SOHO/CDS and soft X-ray (SXR) images from Yohkoh/SXT. We found that flux emergence occurred near one end of the filament, and that both this emergence and resulting microflaring in SXRs and EUV were temporally and spatially closely related to the start of the filament's slow rise. Intensity changes (dimmings and brightenings) in the EIT and SXT images indicate that fields far removed from the erupting core were involved in the eruption, and that breakout-type reconnection did occur. Our observations allow us to investigate whether breakout was the trigger of the eruption, or merely a consequence of a more fundamental eruption process such as tether cutting or MHD instability occurring in a complex magnetic environment.

Sterling, A. C.; Moore, R. L.; Harra, L. K.

2006-01-01

282

Transcriptional Regulation of the CmeABC Multidrug Efflux Pump and the KatA Catalase by CosR in Campylobacter jejuni  

PubMed Central

CosR is an essential response regulator in Campylobacter jejuni, a major food-borne pathogen causing enteritis worldwide. A transcriptomic analysis performed in this study discovered 93 genes whose transcriptional levels were changed >2-fold due to the repression of CosR expression by antisense peptide nucleic acid. The identified CosR-regulated genes are involved in various cellular functions, such as energy production, protein synthesis and folding, flagellum biogenesis, and lipid metabolism. Interestingly, 17 of the 93 CosR-regulated genes (18.3%) are predicted essential genes, indicating that CosR may participate in the regulation of vital biological processes in C. jejuni. In particular, CosR knockdown increased the transcriptional levels of cmeA, cmeB, and cmeC genes, whose protein product (CmeABC) is an important determinant conferring multidrug resistance in Campylobacter. Negative regulation of cmeABC by CosR was verified by quantitative real-time PCR (qRT-PCR) and PcmeABC::lacZ assay. The results of electrophoretic mobility shift assays (EMSAs) and DNase I footprinting assays demonstrated that CosR directly binds to the cmeABC promoter. Another notable finding is that CosR regulates the transcription of katA, the sole catalase gene in C. jejuni. Further characterization with qRT-PCR, the catalase enzyme assay, EMSA, and DNase I footprinting assays successfully demonstrated that CosR affects the katA transcription and the catalase activity by direct interactions with the katA promoter. The findings in this study clearly demonstrated that CosR regulates resistance mechanisms in C. jejuni by controlling the expression of genes involved in oxidative stress defense and extrusion of toxic compounds out of the cell. PMID:23065977

Hwang, Sunyoung; Zhang, Qijing; Ryu, Sangryeol

2012-01-01

283

Typical CME-IP shock events during the ascending phase of Solar Cycle 24 and their arrival time predictions at Earth  

NASA Astrophysics Data System (ADS)

Predicting arrival times of interplanetary (IP) shocks at the near Earth space is an important ingredient of space weather forecasting because the passage of an IP shock at Earth will compress the magnetosphere and produce corresponding space weather effects. We have developed a new shock arrival time prediction model, called SPM2, based on 551 solar disturbance events during Solar Cycle 23. Here new shock events in Solar Cycle 24 will be used to check the predicting performance of SPM2. 35 typical CME-IP shock events during the ascending phase of Solar Cycle 24 (2009-2013) with near-simultaneous coronagraph observations of CMEs and metric type II radio bursts are adopted as the sample events. Comparisons between the initial shock speed calculated from the type II burst drifting rate and the CME speed derived from coronagraph observations are investigated. It is found that the multi-spacecraft coronagraph observations combined with appropriate CME leading edge fitting model can give a more reliable CME radial speed than the type II burst shock speed. Then, SPM2 and an empirical model, which input the type II shock speed and CME speed respectively, are used to give the arrival time prediction of the associated IP shocks at the Earth orbit. The predicting precision of the empirical model would become better if the CME is tracked to a larger helio-distance. The prediction of SPM2 gives a similar predicting accuracy even its input parameters contain larger uncertainties. On this sense, the potential capability of the SPM2 model is also discussed in terms of real-time shock arrival time forecasts.

Zhao, X.; Feng, X.

2013-12-01

284

Modeling the radiation belt electron response to CME-driven storms: the first year of the Van Allen Probes (Invited)  

NASA Astrophysics Data System (ADS)

Recent geomagnetic storms at solar maximum have produced dynamic variations in outer zone radiation belt electron flux measured in detail by the Van Allen Probe twin spacecraft, launched August 30, 2012. Both enhanced flux and sudden dropouts have been observed, which characterize CME-driven storms dominating variability around solar maximum. High time resolution measurements of waves which modulate that variability are also made by the Van Allen Probes. In addition to strong evidence of prompt magnetopause loss provided by the Van Allen Probes and THEMIS spacecraft, enhanced atmospheric precipitation has been observed by the Balloon Array for RBSP Relativistic Electron Losses (BARREL), launched from Antarctica in January to mid-February 2013. Results will be shown from modeling flux enhancements due to plasmasheet electron injection during the October 7 - 9 storm, which produced the largest enhancement seen since launch, along with ULF wave mediated magnetopause loss and loss to the atmosphere. The technique described follows electron test particles in global MHD fields using the Lyon-Fedder-Mobarry MHD code driven by upstream solar wind measurements. Magnetopause location is investigated with the coupled LFM-RCM model. Plasmasheet electrons can be transported inside geosynchronous orbit, acquiring energies ~ 1 MeV, after loss to the magnetopause and to the atmosphere depletes the outer zone immediately following the arrival of CME shocks. The cycle of flux dropout and enhancement during storm intervals is followed by radial diffusion over quiet periods, which can be modeled by a diffusion code.

Hudson, M. K.; Brito, T. V.; Kress, B. T.; Li, Z.; Paral, J.; Toffoletto, F.; Wiltberger, M. J.

2013-12-01

285

Determination of coronal magnetic fields from 10 to 26 R ? using the density compression ratios of CME-driven shocks  

NASA Astrophysics Data System (ADS)

Recently, the estimation of coronal magnetic field using new methods, such as standoff distance method or density compression ratio method has been reported. In the present work, we utilized the density compression ratio of CME-driven shocks for 10 events at 29 different locations in the upper solar corona (10-26 R ?) and determined the coronal magnetic field for two different adiabatic indices ( ?=4/3 and 5/3). In addition, radial dependence of shock parameters in the corona is studied. It is found that the magnetic field estimated in the above range agree with the general trend. In addition, we obtained a radial profile of magnetic field [ B( R)=623 R -1.4] in the entire upper corona (3-30 R ?) by combining the magnetic field estimated by Kim et al. (Astrophys. J. 746:118, 2012) in the range 3-15 R ? and that estimated in the present study in the range (10-26 R ?). The power-law indices are nearly in agreement with recent results of CME-driven shocks reported in the literature. The results are discussed with the comparison of newly reported coronal magnetic field values obtained by different techniques and found that the power-law relation closely follow the literature values.

Shanmugaraju, A.; Suresh, K.; Moon, Y.-J.

2014-05-01

286

RECONNECTION OUTFLOWS AND CURRENT SHEET OBSERVED WITH HINODE/XRT IN THE 2008 APRIL 9 'CARTWHEEL CME' FLARE  

SciTech Connect

Supra-arcade downflows (SADs) have been observed with Yohkoh/SXT (soft X-rays (SXR)), TRACE (extreme ultraviolet (EUV)), SOHO/LASCO (white light), SOHO/SUMER (EUV spectra), and Hinode/XRT (SXR). Characteristics such as low emissivity and trajectories, which slow as they reach the top of the arcade, are consistent with post-reconnection magnetic flux tubes retracting from a reconnection site high in the corona until they reach a lower-energy magnetic configuration. Viewed from a perpendicular angle, SADs should appear as shrinking loops rather than downflowing voids. We present X-ray Telescope (XRT) observations of supra-arcade downflowing loops (SADLs) following a coronal mass ejection (CME) on 2008 April 9 and show that their speeds and decelerations are consistent with those determined for SADs. We also present evidence for a possible current sheet observed during this flare that extends between the flare arcade and the CME. Additionally, we show a correlation between reconnection outflows observed with XRT and outgoing flows observed with LASCO.

Savage, Sabrina L.; McKenzie, David E.; Longcope, Dana W. [Department of Physics, Montana State University, P.O. Box 173840, Bozeman, MT 59717-3840 (United States); Reeves, Katharine K. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street MS 58, Cambridge, MA 02138 (United States); Forbes, Terry G. [Institute for the Study of Earth, Oceans, and Space (EOS), University of New Hampshire, 39 College Road, Durham, NH 03824 (United States)

2010-10-10

287

Polarimetric localization: A new tool for calculating the CME speed and direction of propagation in near-real time  

NASA Astrophysics Data System (ADS)

The polarimetric localization technique uses the percent polarization observed by a single coronagraph to obtain a three-dimensional reconstruction of a coronal mass ejection (CME). We use this technique to analyze STEREO/SECCHI/COR2 beacon data for 12 different events at spacecraft separations ranging from 9° to 127°. To determine if the technique is efficacious, we compare the three-dimensional location and velocity, including speed and direction, computed by polarimetric localization to the same quantities computed by geometric localization. The geometric localization technique utilizes a series of lines of sight from two space-based coronagraphs to determine gross propagation characteristics of CMEs in three-dimensional space. In particular, we present a detailed comparison of the techniques for two events: the first example is from very early on in the mission, on 23 May 2007, when the spacecraft separation was only 9.2°, and the second event is from 12 December 2008, when the spacecraft were almost in quadrature. We find that the two techniques yield comparable CME velocities; furthermore, both are straightforward to apply and they can be used in near-real time. In conclusion, we believe that these techniques promise a substantial improvement in our capability to locate and characterize CMEs for forecasting, as well as research purposes.

de Koning, Curt A.; Pizzo, V. J.

2011-03-01

288

Current perspectives on intrathecal drug delivery  

PubMed Central

Advances in intrathecal analgesia and intrathecal drug delivery systems have allowed for a range of medications to be used in the control of pain and spasticity. This technique allows for reduced medication doses that can decrease the side effects typically associated with oral or parenteral drug delivery. Recent expert panel consensus guidelines have provided care paths in the treatment of nociceptive, neuropathic, and mixed pain syndromes. While the data for pain relief, adverse effect reduction, and cost-effectiveness with cancer pain control are compelling, the evidence is less clear for noncancer pain, other than spasticity. Physicians should be aware of mechanical, pharmacological, surgical, and patient-specific complications, including possible granuloma formation. Newer intrathecal drug delivery systems may allow for better safety and quality of life outcomes. PMID:25395870

Bottros, Michael M; Christo, Paul J

2014-01-01

289

Optically generated ultrasound for enhanced drug delivery  

DOEpatents

High frequency acoustic waves, analogous to ultrasound, can enhance the delivery of therapeutic compounds into cells. The compounds delivered may be chemotherapeutic drugs, antibiotics, photodynamic drugs or gene therapies. The therapeutic compounds are administered systemically, or preferably locally to the targeted site. Local delivery can be accomplished through a needle, cannula, or through a variety of vascular catheters, depending on the location of routes of access. To enhance the systemic or local delivery of the therapeutic compounds, high frequency acoustic waves are generated locally near the target site, and preferably near the site of compound administration. The acoustic waves are produced via laser radiation interaction with an absorbing media and can be produced via thermoelastic expansion, thermodynamic vaporization, material ablation, or plasma formation. Acoustic waves have the effect of temporarily permeabilizing the membranes of local cells, increasing the diffusion of the therapeutic compound into the cells, allowing for decreased total body dosages, decreased side effects, and enabling new therapies.

Visuri, Steven R. (Livermore, CA); Campbell, Heather L. (Baltimore, MD); Da Silva, Luiz (Danville, CA)

2002-01-01

290

An operational software tool for the analysis of coronagraph images: Determining CME parameters for input into the WSA-Enlil heliospheric model  

NASA Astrophysics Data System (ADS)

Coronal mass ejections (CMEs)—massive explosions of dense plasma that originate in the lower solar atmosphere and propagate outward into the solar wind—are the leading cause of significant space weather effects within Earth's environment. Computational models of the heliosphere such as WSA-Enlil offer the possibility of predicting whether a given CME will become geo-effective and, if so, the likely time of arrival at Earth. To be meaningful, such a forecast model is dependent upon accurately characterizing key parameters for the CME, notably its speed and direction of propagation, and its angular width. Studies by Zhao et al. (2002) and Xie et al. (2004) suggest that these key CME parameters can be deduced from geometric analysis of the elliptical "halo" forms observed in coronagraph images on spacecraft such as the Solar and Heliospheric Observatory (SOHO) and which result from a CME whose propagation is roughly toward or away from the observer. Both studies assume that the CME presents a circular cross-section and maintains a constant angular width during its radial expansion, the so called "cone model." Development work at the NOAA Space Weather Prediction Center (SWPC) has been concerned with building and testing software tools to allow forecasters to determine these CME parameters routinely within an operational context, a key aspect of transitioning the WSA-Enlil heliospheric model into operations at the National Weather Service. We find "single viewpoint" cone analysis, while a useful start, to be highly problematic in many real-world situations. In particular, it is extremely difficult to establish objectively the correct ellipse that should be applied to a given halo form and that small changes in the exact ellipse chosen can lead to large differences in the deduced CME parameters. The inaccuracies in the technique are particularly evident for analysis of the "nearly circular" elliptical forms which result from CMEs that are propagating directly toward the observer and are therefore the most likely to be geo-effective. In working to resolve this issue we have developed a new three-dimensional (3-D) graphics-based analysis system which seeks to reduce inaccuracies by analyzing a CME using coronagraph images taken concurrently by SOHO and also by the two Solar TErrestrial RElations Observatory (STEREO) spacecraft, which provide additional viewing locations well away from the Sun-Earth line. The resulting "three view" technique has led to the development of the CME Analysis Tool (CAT), an operational software system in routine use at the SWPC as the primary means to determine CME parameters for input into the WSA-Enlil model. Results from the operational WSA-Enlil system are presented: utilizing CAT to provide CME input parameters, we show that, during the first year of operations at SWPC, the WSA-Enlil model has forecasted the arrival of CMEs at Earth with an average error 7.5 h.

Millward, G.; Biesecker, D.; Pizzo, V.; Koning, C. A.

2013-02-01

291

Drug delivery systems for intraperitoneal therapy.  

PubMed

Disorders associated with the peritoneal cavity include peritoneal adhesions and intraperitoneal (IP) malignancies. To prevent peritoneal adhesions, physical barrier devices are used to prevent organs from contacting other structures in the abdomen and forming adhesions, or pharmacological agents that interfere with adhesion formation are administered intraperitoneally. IP malignancies are other disorders confined to the peritoneal cavity, which are treated by combination of surgical removal and chemotherapy of the residual tumor. IP drug delivery helps in the regional therapy of these disorders by providing relatively high concentration and longer half-life of a drug in the peritoneal cavity. Various studies suggest that IP delivery of anti-neoplastic agents is a promising approach for malignancies in the peritoneal cavity compared to the systemic administration. However, IP drug delivery faces several challenges, such as premature clearance of a small molecular weight drug from the peritoneal cavity, lack of target specificity, and poor drug penetration into the target tissues. Previous studies have proposed the use of micro/nanoparticles and/or hydrogel-based systems for prolonging the drug residence time in the peritoneal cavity. This commentary discusses the currently used IP drug delivery systems either clinically or experimentally and the remaining challenges in IP drug delivery for future development. PMID:20198409

Bajaj, Gaurav; Yeo, Yoon

2010-05-01

292

Nanoparticles for Pulmonary Delivery  

Microsoft Academic Search

\\u000a This chapter aims to provide a rational for the use of nanoparticles in pulmonary delivery as well as an overview of strategies\\u000a and physiological implications of nanoparticle delivery to the lungs. Formulation aspects of nanoparticle systems in the form\\u000a of liquid dispersions and inhaled dry powders are also reviewed. The chapter also addresses the expanse of lung toxicology\\u000a research surrounding

Alan B. Watts; Robert O. Williams

293

Oxazole yellow homodimer YOYO-1-labeled DNA: a fluorescent complex that can be used to assess structural changes in DNA following formation and cellular delivery of cationic lipid DNA complexes  

Microsoft Academic Search

To improve transfection efficiency following delivery of plasmid expression vectors using lipid-based carriers, it is crucial to define structural characteristics of the lipid\\/DNA complexes that optimize transgene expression. Due to its strong affinity for DNA and high quantum yield, the fluorescent DNA intercalator YOYO-1 was used as a tool to assess changes in DNA that occur following lipid binding and

Margaret Wong; Spencer Kong; Wieslawa H. Dragowska; Marcel B. Bally

2001-01-01

294

Analysis and interpretation of a fast limb CME with eruptive prominence, C-flare, and EUV dimming  

NASA Astrophysics Data System (ADS)

Aims: Coronal mass ejections or CMEs are large dynamical solar-corona events. The mass balance and kinematics of a fast limb CME, including its prominence progenitor and the associated flare, will be compared with computed magnetic structures to look for their origin and effect. Methods: Multi-wavelength ground-based and spaceborne observations are used to study a fast W-limb CME event of December 2, 2003, taking into account both on and off disk observations. Its erupting prominence is measured at high cadence with the Pic du Midi full H? line-flux imaging coronagraph. EUV images from SOHO/EIT and CORONAS-F/SPIRIT space instruments are processed including difference imaging. SOHO/LASCO images are used to study the mass excess and motions. Computed coronal structures from extrapolated surface magnetic fields are compared to observations. Results: A fast bright expanding coronal loop is identified in the region recorded slightly later by GOES as a C7.2 flare, followed by a brightening and an acceleration phase of the erupting material with both cool and hot components. The total coronal radiative flux dropped by ~7% in the 19.5 nm channel and by 4% in the 17.5 nm channel, revealing a large dimming effect at and above the limb over a 2 h interval. The typical 3-part structure observed 1 h later by the Lasco C2 and C3 coronagraphs shows a core shaped similarly to the eruptive filament/prominence. The total measured mass of the escaping CME (~1.5×1016 g from C2 LASCO observations) definitely exceeds the estimated mass of the escaping cool prominence material although assumptions made to analyze the H? erupting prominence, as well as the corresponding EUV darkening of the filament observed several days before, made this evaluation uncertain by a factor of 2. This mass budget suggests that the event is not confined to the eruption region alone. From the current free extrapolation we discuss the shape of the magnetic neutral surface and a possible scenario leading to an instability, including the small scale dynamics inside and around the filament.

Koutchmy, S.; Slemzin, V.; Filippov, B.; Noens, J.-C.; Romeuf, D.; Golub, L.

2008-05-01

295

Synergy between Efflux Pump CmeABC and Modifications in Ribosomal Proteins L4 and L22 in Conferring Macrolide Resistance in Campylobacter jejuni and Campylobacter coli?  

PubMed Central

Macrolide-resistant mutants of Campylobacter jejuni and Campylobacter coli were selected in vitro using erythromycin and tylosin. These mutants exhibited modifications in the ribosomal proteins L4 (G74D) and L22 (insertions at position 86 or 98). A synergy between the CmeABC efflux pump and these modifications in conferring macrolide resistance was observed. PMID:16940070

Cagliero, Cédric; Mouline, Christian; Cloeckaert, Axel; Payot, Sophie

2006-01-01

296

Synergy between efflux pump CmeABC and modifications in ribosomal proteins L4 and L22 in conferring macrolide resistance in Campylobacter jejuni and Campylobacter coli.  

PubMed

Macrolide-resistant mutants of Campylobacter jejuni and Campylobacter coli were selected in vitro using erythromycin and tylosin. These mutants exhibited modifications in the ribosomal proteins L4 (G74D) and L22 (insertions at position 86 or 98). A synergy between the CmeABC efflux pump and these modifications in conferring macrolide resistance was observed. PMID:16940070

Cagliero, Cédric; Mouline, Christian; Cloeckaert, Axel; Payot, Sophie

2006-11-01

297

Sequence variation in the outer membrane protein-encoding gene cmeC, conferring multidrug resistance among Campylobacter jejuni and Campylobacter coli strains isolated from different hosts.  

PubMed

A novel PCR primer pair was used to detect the presence of cmeC in 131 Campylobacter jejuni and C. coli strains isolated from various hosts (cattle, turkeys, humans, and pigs). DNA sequence analysis revealed a high degree of genetic variation between the two species, while extremely limited genetic variation among isolates of the same species was detected. PMID:17652470

Fakhr, Mohamed K; Logue, Catherine M

2007-10-01

298

Sequence Variation in the Outer Membrane Protein-Encoding Gene cmeC, Conferring Multidrug Resistance among Campylobacter jejuni and Campylobacter coli Strains Isolated from Different Hosts?  

PubMed Central

A novel PCR primer pair was used to detect the presence of cmeC in 131 Campylobacter jejuni and C. coli strains isolated from various hosts (cattle, turkeys, humans, and pigs). DNA sequence analysis revealed a high degree of genetic variation between the two species, while extremely limited genetic variation among isolates of the same species was detected. PMID:17652470

Fakhr, Mohamed K.; Logue, Catherine M.

2007-01-01

299

Quantitative understanding of Forbush decrease drivers based on shock-only and CME-only models using global signature of February 14, 1978 event  

NASA Astrophysics Data System (ADS)

We have studied the Forbush decrease (FD) event that occurred on February 14, 1978 using 43 neutron monitor observatories to understand the global signature of FD. We have studied rigidity dependence of shock amplitude and total FD amplitude. We have found almost the same power law index for both shock phase amplitude and total FD amplitude. Local time variation of shock phase amplitude and maximum depression time of FD have been investigated which indicate possible effect of shock/CME orientation. We have analyzed rigidity dependence of time constants of two phase recovery. Time constants of slow component of recovery phase show rigidity dependence and imply possible effect of diffusion. Solar wind speed was observed to be well correlated with slow component of FD recovery phase. This indicates solar wind speed as possible driver of recovery phase. To investigate the contribution of interplanetary drivers, shock and CME in FD, we have used shock-only and CME-only models. We have applied these models separately to shock phase and main phase amplitudes respectively. This confirms presently accepted physical scenario that the first step of FD is due to propagating shock barrier and second step is due to flux rope of CME/magnetic cloud.

Raghav, Anil; Bhaskar, Ankush; Lotekar, Ajay; Vichare, Geeta; Yadav, Virendra

2014-10-01

300

An essay on terminology, myths,- and known facts: Solar transient-flare-CME-driver gas-piston-BDE-magnetic cloud-shock wave-geomagnetic storm  

Microsoft Academic Search

In the field of solar-terrestrial relations a clear and unique terminology is needed in order to abolish and avoid unnecessary confusion between the scientists from several involved disciplines. For example, the widely used abbreviationCME (for coronal mass ejection) has turned out to be somewhat misleading. Early on it had been known that other than coronal material is often involved in

Rainer Schwenn

1996-01-01

301

Responsibility of a Filament Eruption for the Initiation of a Flare, CME, and Blast Wave, and its Possible Transformation into a Bow Shock  

NASA Astrophysics Data System (ADS)

Multi-instrument observations of two filament eruptions on 24 February and 11 May 2011 suggest the following updated scenario for eruptive flare, coronal mass ejection (CME), and shock wave evolution. An initial destabilization of a filament results in stretching out of the magnetic threads belonging to its body that are rooted in the photosphere along the inversion line. Their reconnection leads to i) heating of parts of the filament or its environment, ii) an initial development of the flare cusp, arcade, and ribbons, iii) an increasing similarity of the filament to a curved flux rope, and iv) to its acceleration. Then the pre-eruption arcade enveloping the filament becomes involved in reconnection according to the standard model and continues to form the flare arcade and ribbons. The poloidal magnetic flux in the curved rope developing from the filament progressively increases and forces its toroidal expansion. This flux rope impulsively expands and produces a magnetohydrodynamical disturbance, which rapidly steepens into a shock. The shock passes through the arcade that expands above the filament and then freely propagates for some time ahead of the CME like a decelerating blast wave. If the CME is slow, then the shock eventually decays. Otherwise, the frontal part of the shock changes into the bow-shock regime. This was observed for the first time in the 24 February 2011 event. When reconnection ceases, the flux rope relaxes and constitutes the CME core-cavity system. The expanding arcade develops into the CME frontal structure. We also found that reconnection in the current sheet of a remote streamer forced by the shock passage results in a running flare-like process within the streamer responsible for a type II burst. The development of dimming and various associated phenomena are discussed.

Grechnev, V. V.; Uralov, A. M.; Kuzmenko, I. V.; Kochanov, A. A.; Chertok, I. M.; Kalashnikov, S. S.

2015-01-01

302

An Ensemble Study of a January 2010 Coronal Mass Ejection (CME): Connecting a Non-obvious Solar Source with Its ICME/Magnetic Cloud  

NASA Astrophysics Data System (ADS)

A distinct magnetic cloud (MC) was observed in-situ at the Solar TErrestrial RElations Observatory (STEREO)-B on 20 - 21 January 2010. About three days earlier, on 17 January, a bright flare and coronal mass ejection (CME) were clearly observed by STEREO-B, which suggests that this was the progenitor of the MC. However, the in-situ speed of the event, several earlier weaker events, heliospheric imaging, and a longitude mismatch with the STEREO-B spacecraft made this interpretation unlikely. We searched for other possible solar eruptions that could have caused the MC and found a faint filament eruption and the associated CME on 14 - 15 January as the likely solar source event. We were able to confirm this source by using coronal imaging from the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI)/EUVI and COR and Solar and Heliospheric Observatory (SOHO)/ Large Angle and Spectrometric Coronograph (LASCO) telescopes and heliospheric imaging from the Solar Mass Ejection Imager (SMEI) and the STEREO/ Heliospheric Imager instruments. We use several empirical models to understand the three-dimensional geometry and propagation of the CME, analyze the in-situ characteristics of the associated ICME, and investigate the characteristics of the MC by comparing four independent flux-rope model fits with the launch observations and magnetic-field orientations. The geometry and orientations of the CME from the heliospheric-density reconstructions and the in-situ modeling are remarkably consistent. Lastly, this event demonstrates that a careful analysis of all aspects of the development and evolution of a CME is necessary to correctly identify the solar counterpart of an ICME/MC.

Webb, D. F.; Bisi, M. M.; de Koning, C. A.; Farrugia, C. J.; Jackson, B. V.; Jian, L. K.; Lugaz, N.; Marubashi, K.; Möstl, C.; Romashets, E. P.; Wood, B. E.; Yu, H.-S.

2014-11-01

303

Alginate based hydrogel as a potential biopolymeric carrier for drug delivery and cell delivery systems: present status and applications.  

PubMed

Alginate is a non-toxic, biocompatible and biodegradable natural polymer with a number of peculiar physicochemical properties for which it has wide applications in drug delivery and cell delivery systems. Hydrogel formation can be obtained by interactions of anionic alginates with multivalent inorganic cations by simple ionotropic gelation method. Hydrophilic polymeric network of three dimensional cross linked structures of hydrogels absorb substantial amount of water or biological fluids. Among the numerous biomaterials used for hydrogel formation alginate has been and will continue to be one of the most important biomaterial. Therefore, in view of the vast literature support, we focus in this review on alginate - based hydrogel as drug delivery and cell delivery carriers for biomedical applications. Various properties of alginates, their hydrogels and also various techniques used for preparing alginate hydrogels have been reviewed. PMID:22998675

Giri, Tapan Kumar; Thakur, Deepa; Alexander, Amit; Ajazuddin; Badwaik, Hemant; Tripathi, Dulal Krishna

2012-11-01

304

Nanomedicine in pulmonary delivery  

PubMed Central

The lung is an attractive target for drug delivery due to noninvasive administration via inhalation aerosols, avoidance of first-pass metabolism, direct delivery to the site of action for the treatment of respiratory diseases, and the availability of a huge surface area for local drug action and systemic absorption of drug. Colloidal carriers (ie, nanocarrier systems) in pulmonary drug delivery offer many advantages such as the potential to achieve relatively uniform distribution of drug dose among the alveoli, achievement of improved solubility of the drug from its own aqueous solubility, a sustained drug release which consequently reduces dosing frequency, improves patient compliance, decreases incidence of side effects, and the potential of drug internalization by cells. This review focuses on the current status and explores the potential of colloidal carriers (ie, nanocarrier systems) in pulmonary drug delivery with special attention to their pharmaceutical aspects. Manufacturing processes, in vitro/in vivo evaluation methods, and regulatory/toxicity issues of nanomedicines in pulmonary delivery are also discussed. PMID:20054434

Mansour, Heidi M; Rhee, Yun-Seok; Wu, Xiao

2009-01-01

305

Systems and Components Fuel Delivery System, Water Delivery System, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Systems and Components - Fuel Delivery System, Water Delivery System, Derrick Crane System, and Crane System Details - Marshall Space Flight Center, F-1 Engine Static Test Stand, On Route 565 between Huntsville and Decatur, Huntsville, Madison County, AL

306

Hydrogen Storage Technologies Hydrogen Delivery  

E-print Network

Hydrogen Storage Technologies Roadmap Hydrogen Delivery Technical Team Roadmap June 2013 #12;This.................................................................................. 13 6. Hydrogen Storage). The Hydrogen Delivery Technical Team is one of 12 U.S. DRIVE technical teams ("tech teams") whose mission

307

Fluid delivery control system  

SciTech Connect

A method of controlling the delivery of fluid to an engine includes receiving a fuel flow rate signal. An electric pump is arranged to deliver fluid to the engine. The speed of the electric pump is controlled based on the fuel flow rate signal.

Hoff, Brian D.; Johnson, Kris William; Algrain, Marcelo C.; Akasam, Sivaprasad

2006-06-06

308

GENE DELIVERY TO BONE  

PubMed Central

Gene delivery to bone is useful both as an experimental tool and as a potential therapeutic strategy. Among its advantages over protein delivery are the potential for directed, sustained and regulated expression of authentically processed, nascent proteins. Although no clinical trials have been initiated, there is a substantial pre-clinical literature documenting the successful transfer of genes to bone, and their intraosseous expression. Recombinant vectors derived from adenovirus, retrovirus and lentivirus, as well as non-viral vectors, have been used for this purpose. Both ex vivo and in vivo strategies, including gene-activated matrices, have been explored. Ex vivo delivery has often employed mesenchymal stem cells (MSCs), partly because of their ability to differentiate into osteoblasts. MSCs also have the potential to home to bone after systemic administration, which could serve as a useful way to deliver transgenes in a disseminated fashion for the treatment of diseases affecting the whole skeleton, such as osteoporosis or osteogenesis imperfecta. Local delivery of osteogenic transgenes, particularly those encoding bone morphogenetic proteins, has shown great promise in a number of applications where it is necessary to regenerate bone. These include healing large segmental defects in long bones and the cranium, as well as spinal fusion and treating avascular necrosis. PMID:22480730

Evans, C. H.

2012-01-01

309

Electronic Document Delivery  

Microsoft Academic Search

The Houston Public Library provides Electronic Document Delivery through Uncover, Magazine Index, and Business Index at the Central Library and the regional branches, as well as to remote users. Patrons use their credit cards to pay any charges. Documents can be printed out from the terminals or sent to the user's fax machine. Though the service is popular, use has

Gene Rollins

1996-01-01

310

Delivery by Cesarean Section  

MedlinePLUS

... a Cesarean section as the best means of delivery. The reason is because breech babies are more difficult to deliver vaginally, and ... Materna El Primer Ano De Su Bebe Raising Twins Newborn Intensive Care, 3rd Edition Heading Home With Your Newborn ... Baby Toddler Preschool Gradeschool Teen Young ...

311

Delivery: A Trauma for Fathers?  

ERIC Educational Resources Information Center

Fathers' reactions to their wives' pregnancies and especially to the actual deliveries are discussed and three case histories are given to illustrate the gradual build up of tension as the father anticipates delivery which often culminates in crises at the time of delivery. Implications for counselor and educators are given. (Author)

Coley, Silas B., Jr.; James, Barbara E.

1976-01-01

312

PECTIN IN CONTROLLED DRUG DELIVERY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Controlled drug delivery remains a research focus for public health to enhance patient compliance, drug efficiency and to reduce the side effects of drugs. Pectin, an edible plant polysaccharide, has shown potential for the construction of drug delivery systems for site-specific drug delivery. Sev...

313

Locoregional Delivery of Adenoviral Vectors  

Microsoft Academic Search

The overall median survival of patients with a malignant glioma is ,1 y. Because malignant gliomas rarely metastasize outside the skull, locoregional treatment strategies, such as gene therapy, are under investigation. Recently, convection-enhanced delivery (CED) has been presented as a method to improve delivery of large molecules. The goal of this study was to evaluate whether CED improves intratumoral delivery

Suzanne M. Verwijnen; Eric Brouwer; Rob C. Hoeben; Marion de Jong; Bertie H. C. G. M. de Leeuw; Peter A. E. Sillevis

314

Peptide and protein delivery using new drug delivery systems.  

PubMed

Pharmaceutical and biotechnological research sorts protein drug delivery systems by importance based on their various therapeutic applications. The effective and potent action of the proteins/peptides makes them the drugs of choice for the treatment of numerous diseases. Major research issues in protein delivery include the stabilization of proteins in delivery devices and the design of appropriate target-specific protein carriers. Many efforts have been made for effective delivery of proteins/peptidal drugs through various routes of administrations for successful therapeutic effects. Nanoparticles made of biodegradable polymers such as poly lactic acid, polycaprolactone, poly(lactic-co-glycolic acid), the poly(fumaric-co-sebacic) anhydride chitosan, and modified chitosan, as well as solid lipids, have shown great potential in the delivery of proteins/peptidal drugs. Moreover, scientists also have used liposomes, PEGylated liposomes, niosomes, and aquasomes, among others, for peptidal drug delivery. They also have developed hydrogels and transdermal drug delivery systems for peptidal drug delivery. A receptor-mediated delivery system is another attractive strategy to overcome the limitation in drug absorption that enables the transcytosis of the protein across the epithelial barrier. Modification such as PEGnology is applied to various proteins and peptides of the desired protein and peptides also increases the circulating life, solubility and stability, pharmacokinetic properties, and antigenicity of protein. This review focuses on various approaches for effective protein/peptidal drug delivery, with special emphasis on insulin delivery. PMID:23662604

Jain, Ashish; Jain, Aviral; Gulbake, Arvind; Shilpi, Satish; Hurkat, Pooja; Jain, Sanjay K

2013-01-01

315

Local delivery of therapeutics for percutaneous coronary intervention.  

PubMed

Percutaneous coronary intervention (PCI) has become a highly effective alternative for the treatment of coronary artery disease. The use of stents has reduced the rates of restenosis by preventing elastic recoil and negative remodeling, however neointima formation still remains an issue. Local drug delivery is an attractive option to maintain effective drug concentrations at the site of arterial injury without risking systemic toxicity. Drug-eluting stents (DESs) are implanted to provide local drug delivery to combat neointima formation by slowing cell proliferation and migration. However, problems still remain with DES use including the non-specificity of therapeutics, incomplete endothelialization leading to late thrombosis, necessity for longer term anti-platelet drug use, and local hypersensitivity to polymer delivery matrices. This review describes recent advances in local drug delivery for the prevention of restenosis. Many different drug therapeutics have been considered, as well as the material properties of the drug delivery systems. Systems for delivery include DESs, balloon catheters, polymeric cuffs and nanoparticles. Our own experience designing a controlled release device for a new therapeutic agent, Serp-1, an anti-inflammatory protein, is briefly presented. The release of Serp-1 can be extended using diffusion controlled release from physically crosslinked poly(vinyl alcohol) hydrogels, where its release properties can be tuned by the processing parameters of the hydrogel. PMID:21696350

Kennedy, Karen L; Lucas, Alexandra R; Wan, Wankei

2011-09-01

316

Synopsis of Diet in Dermatology: A one day CME conducted by the Department of Dermatology, Kasturba Medical College, Manipal, March 3, 2013  

PubMed Central

Food is intricately related to mind and body and is one of the elements sustaining life, in disease as well as in health. There are many myths and misgivings regarding partake of food and its medicinal properties. The Department of Dermatology, Kasturba Medical College (KMC), Manipal organized a continuing medical education (CME) on Diet in Dermatology on 3rd March 2013 focusing on pertinent issues regarding diet and medicinal use of food. PMID:24350027

Prabhu, Smitha S; Nayak, Sudhir UK; Shenoi, Shrutakirthi Damodar; Pai, Sathish Ballambat

2013-01-01

317

Biodegradable polymersomes for drug delivery : circulation kinetics and biodistribution, modulated drug delivery and cellular uptake  

Microsoft Academic Search

In this thesis, the development and characterization of biodegradable and\\/or enzymetriggered\\u000adestabilizable polymersomes (Ps) for controlled and targeted drug delivery are\\u000apresented. In Chapter 1, a general introduction, the aim of the study and structure of the\\u000athesis are given. Scientific background information on the criteria for the formation of Ps\\u000aand methods for their characterization are discussed in Chapter

Jung Seok Lee

2011-01-01

318

Capturing the Three-Dimensional Motion of the 16 June 2010 CME in the STEREO-SECCHI Observations using Scene Flow  

NASA Astrophysics Data System (ADS)

The motion of coronal mass ejections (CMEs) in the heliosphere is governed by the complex interactions of the magnetic field and gas pressure both internal and external to the CME. The two-viewpoint observations of the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) instrument suite abroad the Solar TErrestrial RElations Observatory (STEREO) mission is a unique resource for studying these forces throughout the heliosphere. To access the fullest potential of these data, we first need to apply advanced image analysis tools to deal with the three-dimensional data. Here, we present the application of the computer vision technique of scene flow on the CME observed by SECCHI on 10 June 2010. Scene flow methods estimate the three-dimensional motion of points in the field of view using multiple camera sequences. We use a scene flow algorithm to estimate the three-dimensional velocity at every point on a surface of the 10 June 2010 CME. We discuss how these technique can be used in future research.

Colaninno, R. C.; Vourlidas, A.

2010-12-01

319

Origin Development, and Effects of Coronal Mass Ejections (CMEs): Report from the 2nd International CME Workshop at Elmau Castle, Germany, in February 2003  

NASA Astrophysics Data System (ADS)

The second of three international workshops on Origin, Development, and Effects of Coronal Mass Ejections (CMEs) was held at Elmau castle with about 50 participants. The aim of the workshop is to interpret the observations from CMEs involving scientists from all different disciplines affected. This includes experimenters, ground observers, modellers, and theorists, remote sensing and in-situ observations, and the environments of the solar photosphere, chromosphere, coronal and the interplanetary space out to the outer heliosphere. The work is done mostly within two sets of 4 working groups meeting in parallel and concentrating on specific asp ects of CMEs. To stimulate interdisciplinary cross-fertilisation esp ecially in the second set of working groups participants from different areas using various to ols coop erate. The working groups are: Set I: A: Coronal observations, B: Solar wind and magnetic field measurements, C: Energetic particle observations, D: CME theory and models. Set I I: E: The pre-CME Sun, F: CME-related coronal phenomena, G: Inner heliosphere, H: Outer heliosphere & high latitudes. Preliminary results from the working groups are presented.

Kunow, Horst W.

2003-07-01

320

Transdermal delivery of ketorolac.  

PubMed

A reservoir type transdermal patch for delivery of ketorolac, a potent analgesic agent was studied. The low permeability of skin is the rate-limiting step for delivery of most of the drugs. Studies were carried out to investigate the effect of permeation enhancers on the in vitro permeation of ketorolac across rat skin. The reservoir type transdermal patch was fabricated and the core was filled with gel system of a non ionic polymer HPMC (hydroxypropyl methyl cellulose) formulated in PBS (phosphate buffer saline) solution of pH of 5.4 along with isopropyl alcohol at 25% w/w concentration. Various permeation enhancers' viz. dimethyl sulphoxide, d-limonene, eucalyptus oil and transcutol (diethylene glycol monoethyl ether) were incorporated into the gel system. Permeation enhancement of ketorolac with different enhancers followed the order eucalyptus oil> transcutol> DMSO> d-limonene. Cyclic terpene containing eucalyptus oil was found to be the most promising chemical permeation enhancer for transdermal delivery of ketorolac. The increase in concentration of eucalyptus oil further enhanced drug permeation with maximum flux being achieved at 10% w/w of 66.38 microg/cm(2)/h. Further enhancement of permeation rate of ketorolac across skin was attained by application of abrading gel containing crushed apricot seed onto the skin. There was 5.16 times enhancement and flux of 93.10 microg/cm(2)/h was attained. A reservoir type transdermal patch for delivery of ketorolac thus appears to be feasible of delivering ketorolac across skin. PMID:19252396

Amrish, Chandra; Kumar, Sharma Pramod

2009-03-01

321

Nanovehicular Intracellular Delivery Systems  

PubMed Central

This article provides an overview of principles and barriers relevant to intracellular drug and gene transport, accumulation and retention (collectively called as drug delivery) by means of nanovehicles (NV). The aim is to deliver a cargo to a particular intracellular site, if possible, to exert a local action. Some of the principles discussed in this article apply to noncolloidal drugs that are not permeable to the plasma membrane or to the blood–brain barrier. NV are defined as a wide range of nanosized particles leading to colloidal objects which are capable of entering cells and tissues and delivering a cargo intracelullarly. Different localization and targeting means are discussed. Limited discussion on pharmacokinetics and pharmacodynamics is also presented. NVs are contrasted to micro-delivery and current nanotechnologies which are already in commercial use. Newer developments in NV technologies are outlined and future applications are stressed. We also briefly review the existing modeling tools and approaches to quantitatively describe the behavior of targeted NV within the vascular and tumor compartments, an area of particular importance. While we list “elementary” phenomena related to different level of complexity of delivery to cancer, we also stress importance of multi-scale modeling and bottom-up systems biology approach. PMID:18200527

PROKOP, ALES; DAVIDSON, JEFFREY M.

2013-01-01

322

Single compartment drug delivery.  

PubMed

Drug design is built on the concept that key molecular targets of disease are isolated in the diseased tissue. Systemic drug administration would be sufficient for targeting in such a case. It is, however, common for enzymes or receptors that are integral to disease to be structurally similar or identical to those that play important biological roles in normal tissues of the body. Additionally, systemic administration may not lead to local drug concentrations high enough to yield disease modification because of rapid systemic metabolism or lack of sufficient partitioning into the diseased tissue compartment. This review focuses on drug delivery methods that physically target drugs to individual compartments of the body. Compartments such as the bladder, peritoneum, brain, eye and skin are often sites of disease and can sometimes be viewed as "privileged," since they intrinsically hinder partitioning of systemically administered agents. These compartments have become the focus of a wide array of procedures and devices for direct administration of drugs. We discuss the rationale behind single compartment drug delivery for each of these compartments, and give an overview of examples at different development stages, from the lab bench to phase III clinical trials to clinical practice. We approach single compartment drug delivery from both a translational and a technological perspective. PMID:24798478

Cima, Michael J; Lee, Heejin; Daniel, Karen; Tanenbaum, Laura M; Mantzavinou, Aikaterini; Spencer, Kevin C; Ong, Qunya; Sy, Jay C; Santini, John; Schoellhammer, Carl M; Blankschtein, Daniel; Langer, Robert S

2014-09-28

323

Prospective of guar gum and its derivatives as controlled drug delivery systems  

Microsoft Academic Search

Guar gum is a non-ionic polysaccharide that is found abundantly in nature and has many properties desirable for drug delivery applications. However, due to its high swelling characteristics in aqueous solution, the use of guar gum as delivery carriers is limited. Guar gum can be modified by derivatization, grafting and network formation to improve its property profile for a wide

M. Prabaharan

2011-01-01

324

CME-associated dimmings on the Sun observed with the EUV SPIRIT telescope on the CORONAS-F spacecraft  

NASA Astrophysics Data System (ADS)

Based on observations with the EUV SPIRIT telescope aboard the CORONAS-F spacecraft, we analyze large-scale dimmings on the solar disk initiated by halo-type coronal mass ejections (CMEs). We address four powerful geo-effective eruptive events of November 4, 2001; October 28, 29, and November 18, 2003. The SOHO/EIT telescope did not observe the first event. Considering other events, we demonstrate that the CORONAS-F/SPIRIT and SOHO/EIT data well supplement each other in time and spectral coverage. The spatial coincidence of the main dimmings in different-temperature lines hints at their relation to plasma outflow from partly or completely opened magnetic structures in the transition region and corona. For some dimmings whose appearance is dissimilar in different lines, CME-associated variations of the plasma temperature can play a role as well. Peculiar propagating darkening was detected in the SPIRIT 304 Å band on November 18 between 08:23 and 09:54 UT. Most probably, the darkening is caused by some absorption of the emission in cold material of the erupted filament.

Kuzin, S.; Chertok, I.; Grechnev, V.; Slemzin, V.; Bugaenko, O.; Zhitnik, I.; Ignat'Ev, A.; Pertsov, A.

2006-01-01

325

Source region of the 2003 November 18 CME that led to the strongest magnetic storm of cycle 23  

E-print Network

The super-storm of November 20, 2003 was associated with a high speed coronal mass ejection which originated in the NOAA AR 10501 on November 18. This coronal mass ejection had severe terrestrial consequences leading to a geomagnetic storm with DST index of -472 nT, the strongest of the current solar cycle. In this paper, we attempt to understand the factors that led to the coronal mass ejection on November 18. We have also studied the evolution of the photospheric magnetic field of NOAA AR 10501, the source region of this coronal mass ejection. For this purpose, the MDI line-of-sight magnetograms and vector magnetograms from Solar Flare Telescope, Mitaka, obtained during November, 17-19, 2003 were analysed. In particular, quantitative estimates of the temporal variation in magnetic flux, energy and magnetic field gradient were estimated for the source active region. The evolution of these quantities was studied for the 3-day period with an objective to understand the pre-flare configuration leading up to the moderate flare which was associated with the geo-effective coronal mass ejection. We also examined the chromospheric images recorded in H-alpha from Udaipur Solar Observatory to compare the flare location with regions of different magnetic field and energy. Our observations provide evidence that the flare associated with the CME occurred at a location marked by high magnetic field gradient which led to release of free energy stored in the active region.

N. Srivastava; S. Mathew; R. Louis; T. Wiegelmann

2008-12-30

326

California Integrated Service Delivery Evaluation Report. Phase I  

ERIC Educational Resources Information Center

This study is a formative evaluation of the OneStop Career Center Integrated Service Delivery (ISD) Model within the California Workforce System. The study was sponsored by the California Workforce Investment Board. The study completed four in-depth case studies of California OneStops to describe how they implemented the ISD model which brings…

Moore, Richard W.; Rossy, Gerard; Roberts, William; Chapman, Kenneth; Sanchez, Urte; Hanley, Chris

2010-01-01

327

The transition from face-to-face to online CME facilitation.  

PubMed

This study examines the experiences of nine medical teachers who transitioned from face-to-face teaching to facilitating a course in an online environment. The authors examined the reasons why the teachers agreed to facilitate an online course, the challenges they encountered and their practical solutions, and the advantages and disadvantages they perceived to this teaching environment. Thirty-minute phone interviews were conducted. An iterative process was used to develop the themes and sub-themes for coding. Teachers reported being attracted to the novelty of the new instructional format and saw online learning as an opportunity to reach different learners. They described two facets to the transition associated with the technical and facilitation aspects of online facilitation. They had to adapt their usual teaching materials and determine how they could make the 'classroom' user friendly. They had to determine ways to encourage interaction and facilitate learning. Lack of participation was frustrating for most. This study has implications for those intending to develop online courses. Teacher selection is important as teachers must invest time in course development and teaching and encourage participation. Teacher support is critical for course design, site navigation and mentoring to ensure teachers facilitate online discussion. PMID:17594554

Lockyer, Jocelyn; Sargeant, Joan; Curran, Vernon; Fleet, Lisa

2006-11-01

328

Migration and health service delivery.  

PubMed

Migration has positive and integrative effects on health service delivery. This paper presents initiatives promoting circular migration of diaspora health professionals to contribute to health service delivery and capacity development in their countries of origin. The paper will also highlight the contributions that foreign trained and foreign born health professionals can make to the delivery of migrant friendly health services for diverse multi-cultural populations. PMID:21155421

Davies, A A; Mosca, D; Frattini, C

2010-01-01

329

DELIVERY OF THERAPEUTIC PROTEINS  

PubMed Central

The safety and efficacy of protein therapeutics are limited by three interrelated pharmaceutical issues, in vitro and in vivo instability, immunogenicity and shorter half-lives. Novel drug modifications for overcoming these issues are under investigation and include covalent attachment of poly(ethylene glycol) (PEG), polysialic acid, or glycolic acid, as well as developing new formulations containing nanoparticulate or colloidal systems (e.g. liposomes, polymeric microspheres, polymeric nanoparticles). Such strategies have the potential to develop as next generation protein therapeutics. This review includes a general discussion on these delivery approaches. PMID:20049941

Pisal, Dipak S.; Kosloski, Matthew P.; Balu-Iyer, Sathy V.

2009-01-01

330

H2A Delivery H2A Hydrogen Delivery  

E-print Network

-Truck ­ Tube Trailer -Truck - LH2 -Pipeline -Liquefier -Compressor (one-stage and multi-stage) -Forecourt Compressor -Terminals (gaseous and liquid) #12;H2A Delivery Spreadsheet Features · Yes/no toggle Input User Input Required Calculated Cells #12;H2A Delivery Component Model Hierarchy Component Design

331

Analysis of EIT/LASCO Observations Using Available MHD Models: Investigation of CME Initiation Propagation and Geoeffectiveness  

NASA Technical Reports Server (NTRS)

The Sun's activity drives the variability of geospace (i.e., near-earth environment). Observations show that the ejection of plasma from the sun, called coronal mass ejections (CMEs), are the major cause of geomagnetic storms. This global-scale solar dynamical feature of coronal mass ejection was discovered almost three decades ago by the use of space-borne coronagraphs (OSO-7, Skylab/ATM and P78-1). Significant progress has been made in understanding the physical nature of the CMEs. Observations show that these global-scale CMEs have size in the order of a solar radius (approximately 6.7 x 10(exp 5) km) near the sun, and each event involves a mass of about 10(exp 15) g and an energy comparable to that of a large flare on the order of 10(exp 32) ergs. The radial propagation speeds of CMEs have a wide range from tens to thousands of kilometers per second. Thus, the transit time to near earth's environment [i.e., 1 AU (astronomical unit)] can be as fast as 40 hours to 100 hours. The typical transit time for geoeffective events is approximately 60-80 h. This paper consists of two parts: 1) A summary of the observed CMEs from Skylab to the present SOHO will be presented. Special attention will be made to SOHO/ LASCO/ EIT observations and their characteristics leading to a geoeffectiv a CME 2) The chronological development of theory and models to interpret the physical nature of this fascinating phenomenon will be reviewed. Finally, an example will be presented to illustrate the geoeffectiveness of the CMEs by using both observation and model.

Wu, S. T.

2001-01-01

332

Radiotherapy delivery during motion  

NASA Astrophysics Data System (ADS)

This paper discusses the 3D dosimetric consequences of radiotherapy delivery during two kinds of motion, (i) the respiratory motion by the patient and (ii) the motion by the gantry while rotating around the patient. Respiratory motion primarily compromises treatments in the thorax and abdomen regions. Several strategies to reduce respiratory motion effects have been developed or are under development. The organ motion could for instance be measured and incorporated in the treatment planning, or adapted to by using respiratory gating and tumour-tracking delivery techniques. Gantry motion is involved in various forms of intensity-modulated arc-therapy techniques. The purpose is to increase the modulation by simultaneously varying the MLC positions, the rotation speed of the gantry, and the dose rate during the treatment. The advantage of these techniques is the increased possibility to deliver a high absorbed dose to the target volume while minimizing the dose to normal tissues. However, the dosimetric uncertainties associated with motion, small fields and steep dose gradients, has to be evaluated in detail, and this requires adequate true 3D dose-verification tools.

Ceberg, Sofie; Bäck, Sven Å. J.

2010-11-01

333

Biodegradable microspheres for protein delivery  

Microsoft Academic Search

In a very short time, since their emergence, the field of controlled delivery of proteins has grown immensely. Because of their relatively large size, they have low transdermal bioavailabilities. Oral bioavailability is generally poor since they are poorly absorbed and easily degraded by proteolytic enzymes in the gastrointestinal tract. Ocular and nasal delivery is also unfavorable due to degradation by

V. R. Sinha; Aman Trehan

2003-01-01

334

Operative Delivery: Yesterday and Today  

Microsoft Academic Search

The normal mechanism of labour leads to spontaneous vaginal delivery in many patients. However, from the beginning of time there has been a requirement for operative intervention to achieve delivery in some women. For centuries, to save the mother in an obstructed labour, the only option was craniotomy to deliver a dead child. The requirement for craniotomy decreased with the

James A. Low

335

Bioresponsive matrices in drug delivery  

Microsoft Academic Search

For years, the field of drug delivery has focused on (1) controlling the release of a therapeutic and (2) targeting the therapeutic to a specific cell type. These research endeavors have concentrated mainly on the development of new degradable polymers and molecule-labeled drug delivery vehicles. Recent interest in biomaterials that respond to their environment have opened new methods to trigger

Jin-Oh You; Dariela Almeda; George JC Ye; Debra T Auguste

2010-01-01

336

CME Expansion as the Driver of Metric Type II Shock Emission as Revealed by Self-consistent Analysis of High-Cadence EUV Images and Radio Spectrograms  

NASA Astrophysics Data System (ADS)

On 13 June 2010, an eruptive event occurred near the solar limb. It included a small filament eruption and the onset of a relatively narrow coronal mass ejection (CME) surrounded by an extreme ultraviolet (EUV) wave front recorded by the Solar Dynamics Observatory's (SDO) Atmospheric Imaging Assembly (AIA) at high cadence. The ejection was accompanied by a GOES M1.0 soft X-ray flare and a Type-II radio burst; high-resolution dynamic spectra of the latter were obtained by the Appareil de Routine pour le Traitement et l'Enregistrement Magnetique de l'Information Spectral (ARTEMIS IV) radio spectrograph. The combined observations enabled a study of the evolution of the ejecta and the EUV wave front and its relationship with the coronal shock manifesting itself as metric Type-II burst. By introducing a novel technique, which deduces a proxy of the EUV compression ratio from AIA imaging data and compares it with the compression ratio deduced from the band-split of the Type-II metric radio burst, we are able to infer the potential source locations of the radio emission of the shock on that AIA images. Our results indicate that the expansion of the CME ejecta is the source for both EUV and radio shock emissions. Early in the CME expansion phase, the Type-II burst seems to originate in the sheath region between the EUV bubble and the EUV shock front in both radial and lateral directions. This suggests that both the nose and the flanks of the expanding bubble could have driven the shock.

Kouloumvakos, A.; Patsourakos, S.; Hillaris, A.; Vourlidas, A.; Preka-Papadema, P.; Moussas, X.; Caroubalos, C.; Tsitsipis, P.; Kontogeorgos, A.

2014-06-01

337

Comparison of interplanetary CME arrival times and solar wind parameters based on the WSA-ENLIL model with three cone types and observations  

NASA Astrophysics Data System (ADS)

We have made a comparison between coronal mass ejection (CME)-associated shock propagations based on the Wang-Sheeley-Arge (WSA)-ENLIL model using three cone types and in situ observations. For this we use 28 full-halo CMEs, whose cone parameters are determined and their corresponding interplanetary shocks were observed at the Earth, from 2001 to 2002. We consider three different cone types (an asymmetric cone model, an ice cream cone model, and an elliptical cone model) to determine 3-D CME cone parameters (radial velocity, angular width, and source location), which are the input values of the WSA-ENLIL model. The mean absolute error of the CME-associated shock travel times for the WSA-ENLIL model using the ice-cream cone model is 9.9 h, which is about 1 h smaller than those of the other models. We compare the peak values and profiles of solar wind parameters (speed and density) with in situ observations. We find that the root-mean-square errors of solar wind peak speed and density for the ice cream and asymmetric cone model are about 190 km/s and 24/cm3, respectively. We estimate the cross correlations between the models and observations within the time lag of ± 2 days from the shock travel time. The correlation coefficients between the solar wind speeds from the WSA-ENLIL model using three cone types and in situ observations are approximately 0.7, which is larger than those of solar wind density (cc ˜0.6). Our preliminary investigations show that the ice cream cone model seems to be better than the other cone models in terms of the input parameters of the WSA-ENLIL model.

Jang, Soojeong; Moon, Y.-J.; Lee, Jae-Ok; Na, Hyeonock

2014-09-01

338

Delivery of bone morphogenetic protein-2 and substance P using graphene oxide for bone regeneration  

PubMed Central

In this study, we demonstrate that graphene oxide (GO) can be used for the delivery of bone morphogenetic protein-2 (BMP-2) and substance P (SP), and that this delivery promotes bone formation on titanium (Ti) implants that are coated with GO. GO coating on Ti substrate enabled a sustained release of BMP-2. BMP-2 delivery using GO-coated Ti exhibited a higher alkaline phosphatase activity in bone-forming cells in vitro compared with bare Ti. SP, which is known to recruit mesenchymal stem cells (MSCs), was co-delivered using Ti or GO-coated Ti to further promote bone formation. SP induced the migration of MSCs in vitro. The dual delivery of BMP-2 and SP using GO-coated Ti showed the greatest new bone formation on Ti implanted in the mouse calvaria compared with other groups. This approach may be useful to improve osteointegration of Ti in dental or orthopedic implants. PMID:24872706

La, Wan-Geun; Jin, Min; Park, Saibom; Yoon, Hee-Hun; Jeong, Gun-Jae; Bhang, Suk Ho; Park, Hoyoung; Char, Kookheon; Kim, Byung-Soo

2014-01-01

339

Pore formation in fluctuating membranes Oded Farago  

E-print Network

in biological membranes is also an important step for drug delivery7 and gene therapy.8 Conse- quently, much adhesion on porous or decorated substrates,18,19 and osmotic swelling.20,21 Most theories of pore formation'' . The formation of a circular hole of radius r0 is driven by the reduction in the tension energy r0 2

Farago, Oded

340

The formation heights of coronal shocks from 2D density and Alfvén speed maps  

NASA Astrophysics Data System (ADS)

Context. Super-Alfvénic shocks associated with coronal mass ejections (CMEs) can produce radio emission known as Type II bursts. In the absence of direct imaging, accurate estimates of coronal electron densities, magnetic field strengths, and Alfvén speeds are required to calculate the kinematics of shocks. To date, 1D radial models have been used, but these are not appropriate for shocks propagating in non-radial directions. Aims: Here, we study a coronal shock wave associated with a CME and Type II radio burst using 2D electron density and Alfvén speed maps to determine the locations that shocks are excited as the CME expands through the corona. Methods: Coronal density maps were obtained from emission measures derived from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) and polarized brightness measurements from the Large Angle and Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory (SOHO). Alfvén speed maps were calculated using these density maps and magnetic field extrapolations from the Helioseismic and Magnetic Imager (SDO/HMI). The computed density and Alfvén speed maps were then used to calculate the shock kinematics in non-radial directions. Results: Using the kinematics of the Type II burst and associated shock, we find our observations to be consistent with the formation of a shock located at the CME flanks where the Alfvén speed has a local minimum. Conclusions: The 1D density models are not appropriate for shocks that propagate non-radially along the flanks of a CME. Rather, the 2D density, magnetic field and Alfvén speed maps described here give a more accurate method for determining the fundamental properties of shocks and their relation to CMEs.

Zucca, Pietro; Carley, Eoin P.; Bloomfield, D. Shaun; Gallagher, Peter T.

2014-04-01

341

Space age health care delivery  

NASA Technical Reports Server (NTRS)

Space age health care delivery is being delivered to both NASA astronauts and employees with primary emphasis on preventive medicine. The program relies heavily on comprehensive health physical exams, health education, screening programs and physical fitness programs. Medical data from the program is stored in a computer bank so epidemiological significance can be established and better procedures can be obtained. Besides health care delivery to the NASA population, NASA is working with HEW on a telemedicine project STARPAHC, applying space technology to provide health care delivery to remotely located populations.

Jones, W. L.

1977-01-01

342

DIRECT EVIDENCE FOR A FAST CORONAL MASS EJECTION DRIVEN BY THE PRIOR FORMATION AND SUBSEQUENT DESTABILIZATION OF A MAGNETIC FLUX ROPE  

SciTech Connect

Magnetic flux ropes play a central role in the physics of coronal mass ejections (CMEs). Although a flux-rope topology is inferred for the majority of coronagraphic observations of CMEs, a heated debate rages on whether the flux ropes pre-exist or whether they are formed on-the-fly during the eruption. Here, we present a detailed analysis of extreme-ultraviolet observations of the formation of a flux rope during a confined flare followed about 7 hr later by the ejection of the flux rope and an eruptive flare. The two flares occurred during 2012 July 18 and 19. The second event unleashed a fast (>1000 km s{sup -1}) CME. We present the first direct evidence of a fast CME driven by the prior formation and destabilization of a coronal magnetic flux rope formed during the confined flare on July 18.

Patsourakos, S. [Department of Physics, University of Ioannina, Section of Astrogeophysics, Ioannina (Greece)] [Department of Physics, University of Ioannina, Section of Astrogeophysics, Ioannina (Greece); Vourlidas, A. [Space Sciences Division, Naval Research Laboratory, Washington, DC (United States)] [Space Sciences Division, Naval Research Laboratory, Washington, DC (United States); Stenborg, G. [School of Physics, Astronomy, and Computational Sciences (SPACS), College of Science George Mason University, Fairfax, VA (United States)] [School of Physics, Astronomy, and Computational Sciences (SPACS), College of Science George Mason University, Fairfax, VA (United States)

2013-02-20

343

Italy. [CME Country Reports].  

ERIC Educational Resources Information Center

Ever since 1946, increased emigration in Italy has been paralleled by a slow but steady increase in educational activity. In 1971, Law No. 153 was adopted which provides for special educational arrangements to be made for migrant workers and their spouses adopted by the Italian Government are based on the need for Italian children to: (1) be…

Council of Europe, Strasbourg (France). Documentation Center for Education in Europe.

344

Netherlands. [CME Country Reports].  

ERIC Educational Resources Information Center

Under the 1969 Compulsory Education Act in the Netherlands, immigrant parents of school age children are obliged to enroll them in a primary school. Chief problems in the education of these children are the Dutch language, and a great cultural diversity in the children's backgrounds. Another problem relates to length of residence -- although the…

Council of Europe, Strasbourg (France). Documentation Center for Education in Europe.

345

Anatomy of a CME  

NSDL National Science Digital Library

This is an activity about graph interpretation. Learners will compare, interpret, and discuss four graphs of the speed, temperature, magnetic field strength, and density of a coronal mass ejection as it swept past Earth in 1997. This is the third activity in the Solar Storms and You: Exploring the Wind from the Sun educator guide.

2012-08-03

346

France. [CME Country Reports].  

ERIC Educational Resources Information Center

In France, the 1882 Compulsory Education Act includes both French and foreign children. Since then, the need to go further than this general principle of non-discrimination and to undertake specific action for immigrants, both adults and children, has been recognized. Since 1970, the Ministry of Education has been directly responsible for this…

Council of Europe, Strasbourg (France). Documentation Center for Education in Europe.

347

Luxembourg. [CME Country Reports].  

ERIC Educational Resources Information Center

The Luxembourg policy for providing education and training for migrant workers and their children is to offer the same opportunities as for nationals. The main difficulties so far are providing for children aged 9 and over and teaching students, especially those with a Latin language as their mother tongue, the languages used in the host schools…

Council of Europe, Strasbourg (France). Documentation Center for Education in Europe.

348

Spain. [CME Country Reports].  

ERIC Educational Resources Information Center

Initially, the Spanish Emigration Institute (Ministry of Labour) endeavored to meet the educational needs of Spanish emigrants. However, this proved to be inadequate as the number of emigrants rose. Therefore, in 1969 the Ministry of Labour and the Ministry of Education and Science divided the responsibility between them and set up a Schools…

Council of Europe, Strasbourg (France). Documentation Center for Education in Europe.

349

DETERMINATION OF THE HELIOSPHERIC RADIAL MAGNETIC FIELD FROM THE STANDOFF DISTANCE OF A CME-DRIVEN SHOCK OBSERVED BY THE STEREO SPACECRAFT  

SciTech Connect

We report on the determination of radial magnetic field strength in the heliocentric distance range from 6 to 120 solar radii (R {sub Sun }) using data from Coronagraph 2 (COR2) and Heliospheric Imager I (HI1) instruments on board the Solar Terrestrial Relations Observatory spacecraft following the standoff-distance method of Gopalswamy and Yashiro. We measured the shock standoff distance of the 2008 April 5 coronal mass ejection (CME) and determined the flux-rope curvature by fitting the three-dimensional shape of the CME using the Graduated Cylindrical Shell model. The radial magnetic field strength is computed from the Alfven speed and the density of the ambient medium. We also compare the derived magnetic field strength with in situ measurements made by the Helios spacecraft, which measured the magnetic field at the heliocentric distance range from 60 to 215 R {sub Sun }. We found that the radial magnetic field strength decreases from 28 mG at 6 R {sub Sun} to 0.17 mG at 120 R {sub Sun }. In addition, we found that the radial profile can be described by a power law.

Poomvises, Watanachak; Gopalswamy, Nat; Yashiro, Seiji; Kwon, Ryun-Young [NASA GSFC, Greenbelt, MD 20771 (United States); Olmedo, Oscar [Space Science Division, U.S. Naval Research Laboratory, Washington, DC 20375 (United States)

2012-10-20

350

Empirical Relationship Between CME Parameters and Geo-effectiveness of Halo CMEs in the Rising Phase of Solar Cycle 24 (2011 - 2013)  

NASA Astrophysics Data System (ADS)

We analyzed the physical characteristics of 40 halo coronal mass ejections (CMEs) and their geo-effective parameters observed during the period 2011 to 2013 in the rising phase of Solar Cycle 24. Out of all halo CMEs observed by SOHO/LASCO, we selected 40 halo CMEs and investigated their geomagnetic effects. In particular, we estimated the CME direction parameter (DP) from coronagraph observations, and we obtained the geomagnetic storm disturbance index (Dst) value corresponding to each event by following certain criteria. We studied the correlation between near-Sun parameters of CMEs such as speed and DP with Dst. For this new set of events in the current solar cycle, the relations are found to be consistent with those of previous studies. When the direction parameter increases, the Dst value also increases for symmetrical halo CME ejections. If DP>0.6, these events produce high Dst values. In addition, the intensity of geomagnetic storm calculated using an empirical model with the near-Sun parameters is nearly equal to the observed values. More importantly, we find that the geo-effectiveness in the rising phase of Solar Cycle 24 is much weaker than that in Cycle 23.

Shanmugaraju, A.; Syed Ibrahim, M.; Moon, Y.-J.; Mujiber Rahman, A.; Umapathy, S.

2015-04-01

351

Determination of the Heliospheric Radial Magnetic Field from the Standoff Distance of a CME-Driven Shock Observed by the Stereo Spacecraft  

NASA Technical Reports Server (NTRS)

We report on the determination of radial magnetic field strength in the heliocentric distance range from 6 to 120 solar radii (R-solar) using data from Coronagraph 2 (COR2) and Heliospheric Imager I (HI1) instruments on board the Solar Terrestrial Relations Observatory spacecraft following the standoff-distance method of Gopalswamy & Yashiro. We measured the shock standoff distance of the 2008 April 5 coronal mass ejection (CME) and determined the flux-rope curvature by fitting the three-dimensional shape of the CME using the Graduated Cylindrical Shell model. The radial magnetic field strength is computed from the Alfven speed and the density of the ambient medium. We also compare the derived magnetic field strength with in situ measurements made by the Helios spacecraft, which measured the magnetic field at the heliocentric distance range from 60 to 215 R-solar.We found that the radial magnetic field strength decreases from 28 mG at 6 R-solar to 0.17 mG at 120 R-solar. In addition, we found that the radial profile can be described by a power law.

Poomvises, Watanachak; Gopalswamy, Nat; Yashiro, Seiji; Kwon, Ryun-Young; Olmedo, Oscar

2012-01-01

352

Nanoparticles for Targeted Drug Delivery  

E-print Network

Nanoparticles were synthesized and modified for target drug delivery. The research involved the aqueous synthesis of near infrared (NIR) sensitive Au-Au2S nanoparticles. An anti-cancer drug (cis-platin) ...

Chow, Gan-Moog

353

Variable delivery, fixed displacement pump  

SciTech Connect

A variable delivery, fixed displacement pump comprises a plurality of pistons reciprocated within corresponding cylinders in a cylinder block. The pistons are reciprocated by rotation of a fixed angle swash plate connected to the pistons. The pistons and cylinders cooperate to define a plurality of fluid compression chambers each have a delivery outlet. A vent port is provided from each fluid compression chamber to vent fluid therefrom during at least a portion of the reciprocal stroke of the piston. Each piston and cylinder combination cooperates to close the associated vent port during another portion of the reciprocal stroke so that fluid is then pumped through the associated delivery outlet. The delivery rate of the pump is varied by adjusting the axial position of the swash plate relative to the cylinder block, which varies the duration of the piston stroke during which the vent port is closed.

Sommars, Mark F. (Sparland, IL)

2001-01-01

354

Driving delivery vehicles with ultrasound.  

PubMed

Therapeutic applications of ultrasound have been considered for over 40 years, with the mild hyperthermia and associated increases in perfusion produced by ultrasound harnessed in many of the earliest treatments. More recently, new mechanisms for ultrasound-based or ultrasound-enhanced therapies have been described, and there is now great momentum and enthusiasm for the clinical translation of these techniques. This dedicated issue of Advanced Drug Delivery Reviews, entitled "Ultrasound for Drug and Gene Delivery," addresses the mechanisms by which ultrasound can enhance local drug and gene delivery and the applications that have been demonstrated at this time. In this commentary, the identified mechanisms, delivery vehicles, applications and current bottlenecks for translation of these techniques are summarized. PMID:18479775

Ferrara, Katherine W

2008-06-30

355

Driving delivery vehicles with ultrasound ?  

PubMed Central

Therapeutic applications of ultrasound have been considered for over 40 years, with the mild hyperthermia and associated increases in perfusion produced by ultrasound harnessed in many of the earliest treatments. More recently, new mechanisms for ultrasound-based or ultrasound-enhanced therapies have been described, and there is now great momentum and enthusiasm for the clinical translation of these techniques. This dedicated issue of Advanced Drug Delivery Reviews, entitled “Ultrasound for Drug and Gene Delivery,” addresses the mechanisms by which ultrasound can enhance local drug and gene delivery and the applications that have been demonstrated at this time. In this commentary, the identified mechanisms, delivery vehicles, applications and current bottlenecks for translation of these techniques are summarized. PMID:18479775

Ferrara, Katherine W.

2009-01-01

356

PEGylated Cationic Polylactides for Hybrid Biosynthetic Gene Delivery.  

PubMed

Genetic vaccination is predicated on the underlying principle that diseases can be prevented by the controlled introduction of genetic material encoding antigenic proteins from pathogenic organisms to elicit the formation of protective immune responses. Driving this process is the choice of carrier that is responsible for navigating the obstacles associated with gene delivery. In this work, we expand upon a novel class of hybrid biosynthetic gene delivery vectors that are composed of a biomaterial outer coating and a bacterial (Escherichia coli) inner core. Specifically, a series of newly developed biodegradable cationic polylactides (CPLAs) and their PEGylated variants were selected to investigate the role of low polydispersity index (PDI), charge density, and PEGylation upon hybrid vector assembly and gene delivery efficacy. Upon assembly, hybrid vectors mediated increased gene delivery beyond that of the individual bacterial vector in isolation, including assays with increasing medium protein content to highlight shielding properties afforded by the PEG-functionalized CPLA component. Furthermore, after extensive characterization of surface deposition of the polymer, results prompted a new model for describing hybrid vector assembly that includes cellular coating and penetration of the CPLA component. In summary, these results provide new options and insight toward the assembly and application of next-generation hybrid biosynthetic gene delivery vectors. PMID:25625426

Jones, Charles H; Chen, Chih-Kuang; Chen, Mingfu; Ravikrishnan, Anitha; Zhang, Hanguang; Gollakota, Akhila; Chung, Taichun; Cheng, Chong; Pfeifer, Blaine A

2015-03-01

357

Boronate-Mediated Biologic Delivery  

PubMed Central

Inefficient cellular delivery limits the landscape of macromolecular drugs. Boronic acids readily form boronate esters with the 1,2- and 1,3-diols of saccharides, such as those that coat the surface of mammalian cells. Here pendant boronic acids are shown to enhance the cytosolic delivery of a protein toxin. Thus, boronates are a non-cationic carrier that can deliver a polar macromolecule into mammalian cells. PMID:22303837

Ellis, Gregory A.; Palte, Michael J.; Raines, Ronald T.

2012-01-01

358

Nonviral Vectors for Gene Delivery  

E-print Network

of the liver. After injections of adenovirus carrying the corrected genes, the patient died from a massive immune response. Other challenges include limitations in target cell specificity and high cost associated with the vector production. On the other... with the formulation, toxicity and immunogenicity. Based on the type of the physical methods employed, these can be categorized as direct injection hydrodynamic, electroporation, ultrasound-mediated delivery, laser irradiation, magnetic force mediated delivery...

Baoum, Abdulgader Ahmed

2011-04-26

359

Development of insulin delivery systems.  

PubMed

Delivery system of insulin is vital for its acceptance and adherence to therapy for achieving the glycemic targets. Enormous developments have occurred in the delivery system of insulin during the last twenty years and each improvement was aimed at two common goals: patients convenience and better glycemic control. Till to date, the various insulin delivery systems are: syringes/vials, injection aids, jet injectors, transmucosal delivery, transdermal delivery, external insulin infusion pump, implantable insulin pumps, insulin pens and insulin inhalers. Syringe/vial is the oldest and conventional method, still widely used and relatively cheaper. Modern plastic syringes are disposable, light weight with microfine needle for patients convenience and comfort. Oral route could be the most acceptable and viable, if the barriers can be overcome and under extensive trial. Insulin pen device is an important milestone in the delivery system of insulin as it is convenient, discrete, painless, attractive, portable with flexible life style and improved quality of life. More than 80% of European diabetic patients are using insulin pen. Future digital pen will have better memory option, blood glucose monitoring system, insulin dose calculator etc. Insulin infusion pump is a good option for the children, busy patients with flexible lifestyle and those who want to avoid multiple daily injections. Pulmonary route of insulin delivery is a promising, effective, non-invasive and acceptable alternative method. Exubera, the world first insulin inhaler was approved by FDA in 28 January 2006. But due to certain limitations, it has been withdrawn from the market in October 2007. The main concern of inhaled insulin are: long term pulmonary safety issues, cost effectiveness and user friendly device. In future, more acceptable and cost effective insulin inhaler will be introduced. Newer avenues are under extensive trial for better future insulin delivery systems. PMID:18285745

Siddiqui, N I; Siddiqui, Ni; Rahman, S; Nessa, A

2008-01-01

360

Radiation delivery system and method  

DOEpatents

A radiation delivery system and method are described. The system includes a treatment configuration such as a stent, balloon catheter, wire, ribbon, or the like, a portion of which is covered with a gold layer. Chemisorbed to the gold layer is a radiation-emitting self-assembled monolayer or a radiation-emitting polymer. The radiation delivery system is compatible with medical catheter-based technologies to provide a therapeutic dose of radiation to a lesion following an angioplasty procedure.

Sorensen, Scott A. (Overland Park, KS); Robison, Thomas W. (Los Alamos, NM); Taylor, Craig M. V. (Jemez Springs, NM)

2002-01-01

361

Electroporation-mediated gene delivery.  

PubMed

Electroporation has been used extensively to transfer DNA to bacteria, yeast, and mammalian cells in culture for the past 30 years. Over this time, numerous advances have been made, from using fields to facilitate cell fusion, delivery of chemotherapeutic drugs to cells and tissues, and most importantly, gene and drug delivery in living tissues from rodents to man. Electroporation uses electrical fields to transiently destabilize the membrane allowing the entry of normally impermeable macromolecules into the cytoplasm. Surprisingly, at the appropriate field strengths, the application of these fields to tissues results in little, if any, damage or trauma. Indeed, electroporation has even been used successfully in human trials for gene delivery for the treatment of tumors and for vaccine development. Electroporation can lead to between 100 and 1000-fold increases in gene delivery and expression and can also increase both the distribution of cells taking up and expressing the DNA as well as the absolute amount of gene product per cell (likely due to increased delivery of plasmids into each cell). Effective electroporation depends on electric field parameters, electrode design, the tissues and cells being targeted, and the plasmids that are being transferred themselves. Most importantly, there is no single combination of these variables that leads to greatest efficacy in every situation; optimization is required in every new setting. Electroporation-mediated in vivo gene delivery has proven highly effective in vaccine production, transgene expression, enzyme replacement, and control of a variety of cancers. Almost any tissue can be targeted with electroporation, including muscle, skin, heart, liver, lung, and vasculature. This chapter will provide an overview of the theory of electroporation for the delivery of DNA both in individual cells and in tissues and its application for in vivo gene delivery in a number of animal models. PMID:25620008

Young, Jennifer L; Dean, David A

2015-01-01

362

Advances in Gene Delivery Systems  

PubMed Central

The transfer of genes into cells, both in vitro and in vivo, is critical for studying gene function and conducting gene therapy. Methods that utilize viral and nonviral vectors, as well as physical approaches, have been explored. Viral vector-mediated gene transfer employs replication-deficient viruses such as retro-virus, adenovirus, adeno-associated virus and herpes simplex virus. A major advantage of viral vectors is their high gene delivery efficiency. The nonviral vectors developed so far include cationic liposomes, cationic polymers, synthetic peptides and naturally occurring compounds. These nonviral vectors appear to be highly effective in gene delivery to cultured cells in vitro but are significantly less effective in vivo. Physical methods utilize mechanical pressure, electric shock or hydrodynamic force to transiently permeate the cell membrane to transfer DNA into target cells. They are simpler than viral- and nonviral-based systems and highly effective for localized gene delivery. The past decade has seen significant efforts to establish the most desirable method for safe, effective and target-specific gene delivery, and good progress has been made. The objectives of this review are to (i) explain the rationale for the design of viral, nonviral and physical methods for gene delivery; (ii) provide a summary on recent advances in gene transfer technology; (iii) discuss advantages and disadvantages of each of the most commonly used gene delivery methods; and (iv) provide future perspectives. PMID:22200988

Kamimura, Kenya; Suda, Takeshi; Zhang, Guisheng; Liu, Dexi

2011-01-01

363

Local Delivery of Basic Fibroblast Growth Factor (bFGF) Using Adsorbed Silyl-heparin,  

E-print Network

Local Delivery of Basic Fibroblast Growth Factor (bFGF) Using Adsorbed Silyl-heparin, Benzyl for binding. Once adsorbed the silyl-heparin/ FGF was able to induce capillary tube formation of endothelial into the extracellular matrix. The binding of FGFs to heparin/HS results in the formation or stabiliza- tion of dimers

Homes, Christopher C.

364

"Bronchial Artery Delivery of Viral Vectors for Gene delivery in Cystic Fibrosis; Superior to Airway Delivery?"  

PubMed Central

Background Attempts at gene therapy for the pulmonary manifestations of Cystic Fibrosis have relied mainly on airway delivery. However the efficiency of gene transfer and expression in the airway epithelia has not reached therapeutic levels. Access to epithelial cells is not homogenous for a number of reasons and the submucosal glands cannot be reached via the airways. Presentation We propose to inject gene delivery vectors directly into bronchial arteries combined with pre-delivery of vascular endothelial growth factor to increase vascular endothelial permeability and post-delivery flow reduction by balloon occlusion. Thus it may be possible to reach mucous secreting cells of the bronchial luminal epithelium and the submucosal glands in an increased and homogenous fashion. Testing This combination of techniques to the best of our knowledge has not previously been investigated, and may enable us to overcome some of the current limitations to gene therapy for Cystic Fibrosis. PMID:11929614

Bakhai, Ameet; Sheridan, Desmond J; Coutelle, Charles C

2002-01-01

365

Therapeutic angiogenesis: controlled delivery of angiogenic factors  

PubMed Central

Therapeutic angiogenesis aims at treating ischemic diseases by generating new blood vessels from existing vasculature. It relies on delivery of exogenous factors to stimulate neovasculature formation. Current strategies using genes, proteins and cells have demonstrated efficacy in animal models. However, clinical translation of any of the three approaches has proved to be challenging for various reasons. Administration of angiogenic factors is generally considered safe, according to accumulated trials, and offers off-the-shelf availability. However, many hurdles must be overcome before therapeutic angiogenesis can become a true human therapy. This article will highlight protein-based therapeutic angiogenesis, concisely review recent progress and examine critical challenges. We will discuss growth factors that have been widely utilized in promoting angiogenesis and compare their targets and functions. Lastly, since bolus injection of free proteins usually result in poor outcomes, we will focus on controlled release of proteins. PMID:22838066

Chu, Hunghao; Wang, Yadong

2013-01-01

366

This CME/CE conference will examine how we create cities that promote mental health and well-being of urban residents. We will discuss latest practices, policies, and research on the social determinants of urban mental health at community,  

E-print Network

This CME/CE conference will examine how we create cities that promote mental health and well of urban mental health at community, regional, national, and international levels. Intended for mental presents The Social Determinants of URBAN MENTAL HEALTH: Paving the Way Forward This conference is jointly

Illinois at Chicago, University of

367

Bladder Injury During Cesarean Delivery  

PubMed Central

Cesarean section is the most common surgery performed in the United States with over 30% of deliveries occurring via this route. This number is likely to increase given decreasing rates of vaginal birth after cesarean section (VBAC) and primary cesarean delivery on maternal request, which carries the inherent risk for intraoperative complications. Urologic injury is the most common injury at the time of either obstetric or gynecologic surgery, with the bladder being the most frequent organ damaged. Risk factors for bladder injury during cesarean section include previous cesarean delivery, adhesions, emergent cesarean delivery, and cesarean section performed at the time of the second stage of labor. Fortunately, most bladder injuries are recognized at the time of surgery, which is important, as quick recognition and repair are associated with a significant reduction in patient mortality. Although cesarean delivery is a cornerstone of obstetrics, there is a paucity of data in the literature either supporting or refuting specific techniques that are performed today. There is evidence to support double-layer closure of the hysterotomy, the routine use of adhesive barriers, and performing a Pfannenstiel skin incision versus a vertical midline subumbilical incision to decrease the risk for bladder injury during cesarean section. There is also no evidence that supports the creation of a bladder flap, although routinely performed during cesarean section, as a method to reduce the risk of bladder injury. Finally, more research is needed to determine if indwelling catheterization, exteriorization of the uterus, and methods to extend hysterotomy incision lead to bladder injury. PMID:24876830

Tarney, Christopher M.

2013-01-01

368

Buccal and sublingual vaccine delivery.  

PubMed

Because of their large surface area and immunological competence, mucosal tissues are attractive administration and target sites for vaccination. An important characteristic of mucosal vaccination is its ability to elicit local immune responses, which act against infection at the site of pathogen entry. However, mucosal surfaces are endowed with potent and sophisticated tolerance mechanisms to prevent the immune system from overreacting to the many environmental antigens. Hence, mucosal vaccination may suppress the immune system instead of induce a protective immune response. Therefore, mucosal adjuvants and/or special antigen delivery systems as well as appropriate dosage forms are required in order to develop potent mucosal vaccines. Whereas oral, nasal and pulmonary vaccine delivery strategies have been described extensively, the sublingual and buccal routes have received considerably less attention. In this review, the characteristics of and approaches for sublingual and buccal vaccine delivery are described and compared with other mucosal vaccine delivery sites. We discuss recent progress and highlight promising developments in the search for vaccine formulations, including adjuvants and suitable dosage forms, which are likely critical for designing a successful sublingual or buccal vaccine. Finally, we outline the challenges, hurdles to overcome and formulation issues relevant for sublingual or buccal vaccine delivery. PMID:24911355

Kraan, Heleen; Vrieling, Hilde; Czerkinsky, Cecil; Jiskoot, Wim; Kersten, Gideon; Amorij, Jean-Pierre

2014-09-28

369

Crystallization processes in pharmaceutical technology and drug delivery design  

NASA Astrophysics Data System (ADS)

Crystallization is a major technological process for particle formation in pharmaceutical industry and, in addition, plays an important role in defining the stability and drug release properties of the final dosage forms. Industrial and regulatory aspects of crystallization are briefly reviewed with reference to solid-state properties of pharmaceuticals. Crystallization, incorporating wider definition to include precipitation and solid-state transitions, is considered in terms of preparation of materials for direct compression, formation of amorphous, solvated and polymorphic forms, chiral separation of drugs, production of materials for inhalation drug delivery and injections. Finally, recent developments in supercritical fluid particle technology is considered in relationship to the areas discussed.

Shekunov, B. Yu; York, P.

2000-04-01

370

Coordinated Scheduling of Production and Delivery with Production Window and Delivery Capacity Constraints  

NASA Astrophysics Data System (ADS)

This paper considers the coordinated production and delivery scheduling problem. We have a planning horizon consisting of z delivery times each with a unique delivery capacity. Suppose we have a set of jobs each with a committed delivery time, processing time, production window, and profit. The company can earn the profit if the job is produced in its production window and delivered before its committed delivery time. From the company point of view, we are interested in picking a subset of jobs to process and deliver so as to maximize the total profit subject to the delivery capacity constraint. We consider both the single delivery time case and the multiple delivery times case.

Fu, Bin; Huo, Yumei; Zhao, Hairong

371

Adapting Assessment Procedures for Delivery via an Automated Format.  

ERIC Educational Resources Information Center

The Office of Personnel Management (OPM) decided to explore alternative examining procedures for positions covered by the Administrative Careers with America (ACWA) examination. One requirement for new procedures was that they be automated for use with OPM's recently developed Microcomputer Assisted Rating System (MARS), a highly efficient system…

Kelly, Karen L.; And Others

372

Two Distinct Course Formats in the Delivery of Connectivist MOOCs  

ERIC Educational Resources Information Center

Massive Open Online Courses based on the principles of connectivist educational pedagogy known as connectivist MOOCs (c-MOOCs) have been carried out with great success during the last years with hundreds of registered participants. Examples are CCK08 (2008), PLENK2010 (2010), MobiMOOC (2011), EduMOOC (2011), Change11 (2011/12), and LAK12 (2012).…

Rodriguez, C. Osvaldo

2013-01-01

373

Distance Education Quality Course Delivery Framework: A Formative Research Study  

ERIC Educational Resources Information Center

In the Fall 2010 semester, student enrollment in distance education courses increased in the United States to over 6.1 million students taking at least one distance course. Distance education allows institutions to meet increasing demands from the government and business sectors for more graduates in ways that face-to-face courses cannot meet with…

Berta, Michael Raymond

2013-01-01

374

In vivo transdermal delivery of leuprolide using microneedles and iontophoresis.  

PubMed

The objective of this study was to investigate the use of iontophoresis and/or microneedles to enhance transdermal delivery of leuprolide acetate in vivo in hairless rats. Microporation was achieved using 500 ?m long maltose microneedles and pore formation was confirmed using dye binding studies, histology studies, calcein imaging studies, pore permeability index calculation and trans-epidermal water loss measurement. Iontophoresis was performed using liquid reservoir patch with inbuilt silver wire electrode and a current density of 0.1 mA/cm2 was applied for 4 hours. Delivery studies were performed using microneedles and iontophoresis alone and in combination. Passive studies involving delivery through intact skin and injections of drug solution administered subcutaneously served as controls. Blood samples were collected at predetermined time points and plasma samples were analyzed for drug using ELISA. Significantly higher drug levels were detected at the end of 6 hours treatment by microneedles alone treatment (0.98 ± 0.08 ng/ml) as compared to passive (0.36 ± 0.22 ng/ml) delivery (p < 0.05). Further, three times more drug was found to be present systemically with iontophoresis alone (3.47 ± 0.03 ng/ml) or by combination (3.54 ± 0.08 ng/ml) treatments as compared to microneedles alone treatment (p < 0.05) at the end of treatment duration. When compared to iontophoresis alone treatment, combination treatment resulted in faster drug delivery due to propulsion of the drug through the preformed micropores. In conclusion, the use of microneedles and/or iontophoresis seems promising for the transdermal delivery of peptide like leuprolide acetate. PMID:23157712

Sachdeva, Vishal; Zhou, Yingcong; Banga, Ajay K

2013-01-01

375

Maternal Nutrition and Preterm Delivery  

Microsoft Academic Search

\\u000a \\u000a \\u000a Key Points\\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a The rate of preterm delivery in the United States has increased by more than 25% in the past 20 yr.\\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Low weight before pregnancy may be associated with increased risk for preterm delivery.\\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Inadequate weight gain, particularly in the third trimester, may be associated with increased risk for preterm delivery.\\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Fasting and intervals longer

Theresa O. Scholl

376

Organ-targeted high-throughput in vivo biologics screen identifies materials for RNA delivery.  

PubMed

Therapies based on biologics involving delivery of proteins, DNA, and RNA are currently among the most promising approaches. However, although large combinatorial libraries of biologics and delivery vehicles can be readily synthesized, there are currently no means to rapidly characterize them in vivo using animal models. Here, we demonstrate high-throughput in vivo screening of biologics and delivery vehicles by automated delivery into target tissues of small vertebrates with developed organs. Individual zebrafish larvae are automatically oriented and immobilized within hydrogel droplets in an array format using a microfluidic system, and delivery vehicles are automatically microinjected to target organs with high repeatability and precision. We screened a library of lipid-like delivery vehicles for their ability to facilitate the expression of protein-encoding RNAs in the central nervous system. We discovered delivery vehicles that are effective in both larval zebrafish and rats. Our results showed that the in vivo zebrafish model can be significantly more predictive of both false positives and false negatives in mammals than in vitro mammalian cell culture assays. Our screening results also suggest certain structure-activity relationships, which can potentially be applied to design novel delivery vehicles. PMID:25184623

Chang, Tsung-Yao; Shi, Peng; Steinmeyer, Joseph D; Chatnuntawech, Itthi; Tillberg, Paul; Love, Kevin T; Eimon, Peter M; Anderson, Daniel G; Yanik, Mehmet Fatih

2014-10-01

377

Local magnetism in the molecule-based metamagnet [Ru2(O2CMe)4]3[Cr(CN)6] probed with implanted muons  

SciTech Connect

We present a muon-spin relaxation study of local magnetism in the molecule-based metamagnet [Ru2(O2CMe)4]3[Cr(CN)6]. We observe magnetic order with TN = 33 K, although above 25 K the sublattice spins become less rigid and a degree of static magnetic disorder is observed. The comparison of measurements in applied magnetic field with simulations allows us to understand the origin of the muon response across the metamagnetic transition and to map out the phase diagram of the material. Applied hydrostatic pressures of up to 6 kbar lead to an increase in the local magnetic field along with a complex change in the internal magnetic field distribution.

Lancaster, T. [University of Oxford; Pratt, F. L. [ISIS Facility, Rutherford Appleton Laboratory; Blundell, S. J. [University of Oxford; Steele, Andrew J. [University of Oxford; Baker, Peter J. [ISIS Facility, Rutherford Appleton Laboratory; Wright, Jack D. [University of Oxford; Fishman, Randy Scott [ORNL; Miller, Joel S. [University of Utah

2011-01-01

378

Cesarean delivery: counseling issues and complication management.  

PubMed

Nearly one-third of all deliveries in the United States are cesarean deliveries. Compared with spontaneous vaginal delivery, cesarean delivery is associated with increased maternal and neonatal morbidity and mortality. Interventions that decrease the chance of a cesarean delivery include avoiding non-medically indicated induction of labor, avoiding amniotomy, and having a doula present. In North America, the most common reasons for cesarean delivery include elective repeat cesarean delivery, dystocia or failure to progress, malpresentation, and fetal heart rate tracings that suggest fetal distress. Post-cesarean delivery complications include pain, endomyometritis, wound separation/infection, urinary tract infection, gastrointestinal problems, deep venous thrombosis, and septic thrombophlebitis. Women with no risk factors for deep venous thrombosis other than the postpartum state and the operative delivery do not require thromboembolism prophylaxis other than early ambulation. A pregnant woman's decision to attempt a trial of labor after cesarean delivery or have a planned repeat cesarean delivery involves a balancing of maternal and neonatal risks, as well as personal preference after counseling by her physician. Approximately 75% of attempted trials of labor after cesarean delivery are successful. Provision of advanced maternity care practices by family physicians, including serving as primary surgeons for cesarean deliveries, is consistent with the goals of the patient-centered medical home. PMID:25822271

Quinlan, Jeffrey D; Murphy, Neil J

2015-02-01

379

Delivery of Organic Material and Water through Asteroid Impacts  

NASA Astrophysics Data System (ADS)

Meteorites, specifically carbonaceous chondrites, are frequently invoked as the primary source of Earth's water and organic materials, crucial ingredients for the formation of life. We have started developing a dynamical model of the delivery of their parent bodies, primitive low-albedo asteroids, from the asteroid main belt to Earth and to other planetary surfaces.Existing modeling work focuses on time-integrated delivery rates, which are dominated by the Solar System's turbulent youth. We, in turn, aim at calculating instantaneous delivery rates for comparison with instantaneous measurements. In doing so, we take direct account of the asteroid main belt's observed dynamical and physical structure. In particular, we use low albedo (as taken from the WISE catalog) as a proxy for primitive composition.Our first goal is for our model to reproduce the measured rate of micro-meteorite impacts on Earth. We will then calculate improved delivery rates to Mars and other planetary surfaces within the Solar System.Finally, we aim at applying our model to select exo-planetary systems. Far-IR observations of Vega and Fomalhaut reveal the presence of asteroid belts around these stars; dynamical calculations suggest that those are not a rare occurence but should occur rather generically around the location of the frost line. In such planetary systems, asteroids could deliver water and organics to the habitable region. In this sense, our model should lead to the definition of benchmark observables for exoplanet studies using upcoming/proposed IR facilities such as SPICA, METIS, and JWST.

Mueller, Michael; Frantseva, Kateryna; van der Tak, Floris; Helmich, Frank P.

2014-11-01

380

[Basic studies on the nasal delivery of insulin].  

PubMed

Nasal absorption of insulin was discussed to develop a delivery system that targets the systemic circulation or central nervous system. Formation of insulin dimer and hexamer affects not only the diffusivity but also the membrane permeability of insulin via aqueous channels. The Renkin function was used to evaluate penetration pathways of hydrophilic compounds containing insulin through aqueous channels, and pore size and occupancy of the pathways were obtained as the membrane parameters on the basis of the function. Cationic polymers applied on the mucosal membranes as penetration enhancers increased the number of pathways for the hydrophilic compounds in the tight junctions, which suggested that these compounds could be sufficient as additives for the nasal delivery of insulin. However, excess interaction of the cationic enhancers with anionic insulin suppressed insulin permeation, and protection of insulin against degradation in the permeation process was required to improve the nasal absorption. PEGylation of insulin could be a possible way to improve the nasal delivery of insulin. In addition, combination of PEGylated insulin and modified cyclodextrin, which form pseudorotaxanes, can be applicable for further modification of pharmacokinetic and pharmacodynamic properties of insulin. Such well-designed complex systems may be required for specific delivery of insulin to the central nervous system. PMID:23123716

Seki, Toshinobu

2012-01-01

381

Solid lipid nanoparticles: promising therapeutic nanocarriers for drug delivery.  

PubMed

Development of colloidal delivery systems has opened new avenues/frontiers for improving drug delivery. Solid lipid nanoparticles have come up as the latest development in the arena of lipid based colloidal delivery systems after nanoemulsion and liposomes ever since their introduction in the early 1990s. In this review, the authors have made efforts to bring forth the essential and practically relevant aspects of SLNs. This review gives an overview of the preparation methods of solid lipid nanoparticles while mainly focussing on their biological applications including their projected applications in drug delivery. This review critically examines the influential factors governing the formation of SLNs and then discussing in detail the several techniques being utilized for their characterization. This review discusses the drug loading and drug release aspects of SLNs as these are useful biocompatible carriers of lipophilic and to a certain extent hydrophilic drugs. An updated list of drugs encapsulated into various lipids to prepare SLN formulations has been provided. Other relevant aspects pertaining to the clinical use of SLN formulations like their sterilization and storage stability have also been explained. A unique facet of this review is the discussion on the challenging issues of in vivo applications and recent progresses in overcoming these challenges which follows in the end. PMID:25469779

Thukral, Dipti Kakkar; Dumoga, Shweta; Mishra, Anil K

2014-01-01

382

Statins: A new era in local drug delivery  

PubMed Central

Periodontitis is an inflammatory disease of the supporting tissues of the teeth, caused by a group of specific microorganisms. Aggressive forms of periodontitis can be localized or generalized. The concept that localized problem sites may be treated by local drug delivery appears attractive as the antimicrobial agent is delivered within periodontal pockets and the therapy is targeted on specific pathogenic microorganisms. Periodontitis can result in bone resorption creating bony defects, which may cause tooth loss. Various drugs have been studied using local delivery to improve the periodontal health and to achieve periodontal regeneration. Local delivery of antimicrobial agents using controlled release systems should be considered as adjunctive to mechanical debridement for the treatment of localized forms of periodontal destruction. Pharmacological agents offer great promise in this direction. Simvastatin, used for the treatment of hypercholesterolemia, is a universally accepted and relatively inexpensive drug. Local application of simvastatin has been shown to stimulate bone formation in rodents both in vitro and in vivo and in human periodontal ligament cells in vitro. This article reviews the effects of simvastatin as a local delivery and examines its potential role in periodontal regenerative therapy. PMID:23066263

Elavarasu, Sugumari; Suthanthiran, Thanga Kumaran; Naveen, Devisree

2012-01-01

383

The Cultural Geography of Health Care Delivery.  

ERIC Educational Resources Information Center

This article shows how health care delivery is related to cultural or human geography. This is accomplished by describing health care delivery in terms of 12 popular themes of cultural geography. (JDH)

Gesler, Wilbert M.

1987-01-01

384

FastStats: Births -- Method of Delivery  

MedlinePLUS

... this? Submit What's this? Submit Button NCHS Home Births - Method of Delivery Recommend on Facebook Tweet Share ... of all deliveries by Cesarean: 32.7% Source: Births: Final Data for 2013, table 21 [PDF - 1. ...

385

Virtual doctor's office telemedicine delivery system  

E-print Network

delivery services that are two-way telecommunications using a File Transfer Protocol over an Ethernet connection. The system is used to demonstrate effective telemedicine delivery to enable tele-consultation. Virtual instruments are developed for both ends...

Sainath, Paavana

2002-01-01

386

Packaging for a drug delivery microelectromechanical system  

E-print Network

Local drug delivery is a fast expanding field, and has been a center of attention for researchers in medicine in the last decade. Its advantages over systemic drug delivery are clear in cancer therapy, with localized tumors. ...

Ho Duc, Hong Linh, 1978-

2005-01-01

387

Waste feed delivery test and evaluation plan  

SciTech Connect

This plan documents the Waste Feed Delivery Program test and evaluation planning and implementation approach. The purpose of this document is to define and communicate the Waste Feed Delivery Program Test and Evaluation scope, objectives, planning and implementation approach.

O'TOOLE, S.M.

1999-09-30

388

Valuing a Document Delivery System.  

ERIC Educational Resources Information Center

Users of a search/document delivery service in a large engineering firm were surveyed to determine the amount and relevancy of information received, time saved by using the service, dollar value of information received, number of employees using or seeing the information, and any improvement in the firm's competitive position. (EM)

Estabrook, Leigh Stewart

1986-01-01

389

New Methods of Drug Delivery  

Microsoft Academic Search

Conventional forms of drug administration generally rely on pills, eye drops, ointments, and intravenous solutions. Recently, a number of novel drug delivery approaches have been developed. These approaches include drug modification by chemical means, drug entrapment in small vesicles that are injected into the bloodstream, and drug entrapment within pumps or polymeric materials that are placed in desired bodily compartments

Robert Langer

1990-01-01

390

Delivery System, 2003-2004.  

ERIC Educational Resources Information Center

This workshop guide for financial aid administrators provides training in the federal student financial aid delivery system. An introduction enables the participant to share some information about his or her responsibilities and to reflect on the relevance of the training to the job. Session 1, "Application Systems," identifies methods of applying…

Office of Federal Student Aid (ED), Washington, DC.

391

Teleteach Expanded Delivery System: Evaluation.  

ERIC Educational Resources Information Center

In order to meet the demand for Air Force Institute of Technology (AFIT) professional continuing education (PCE) courses within the School of Systems and Logistics and the School of Engineering, the Teleteach Expanded Delivery System (TEDS) for instruction of Air Force personnel at remote locations was developed and evaluated. TEDS uses a device…

Christopher, G. Ronald; Milam, Alvin L.

392

TARGETED DELIVERY OF INHALED PROTEINS  

EPA Science Inventory

ETD-02-047 (Martonen) GPRA # 10108 TARGETED DELIVERY OF INHALED PROTEINS T. B. Martonen1, J. Schroeter2, Z. Zhang3, D. Hwang4, and J. S. Fleming5 1Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Research Triangle Park...

393

Decationized polyplexes for gene delivery.  

PubMed

Gene therapy has received much attention in the field of drug delivery. Synthetic, nonviral gene delivery systems have gained increasing attention as vectors for gene therapy mainly due to a favorable immunogenicity profile and ease of manufacturing as compared to viral vectors. The great majority of these formulations are based on polycationic structures, due to their ability to interact with negatively charged nucleic acids to spontaneously form nanoparticles. In recent years, several polycationic systems have demonstrated high transfection in vitro. However, progress toward clinical applications has been slow, mainly because the cationic nature of these systems leads to intolerable toxicity levels, inappropriate biodistribution and unsatisfactory efficiency in vivo, particularly after systemic administration. Decationized polyplexes are a new class of gene delivery systems that have been developed as an alternative for conventional polycation-based systems. The major innovation introduced by decationized polyplexes is that these systems are based on neutral polymers, without any detrimental effect on the physicochemical stability or encapsulation ability, due to the transient presence of cationic charge and disulfide cross-links between the polymer chains by which the nucleic acids are physically entrapped in the particles. This editorial summarizes the most important features of decationized polyplexes and discusses potential implications for the development of new safe and efficient gene delivery systems. PMID:25425332

Novo, Luís; Mastrobattista, Enrico; van Nostrum, Cornelus F; Lammers, Twan; Hennink, Wim E

2015-04-01

394

Chitosan-based gastrointestinal delivery systems  

Microsoft Academic Search

Chitosan, a natural polymer obtained by alkaline deacetylation of chitin, is non-toxic, biocompatible, and biodegradable. These properties make chitosan a good candidate for the development of conventional and novel gastrointestinal (GI) drug and gene delivery systems. The objective of this review is to summarize the recent applications of chitosan in oral and\\/or buccal delivery, stomach-specific drug delivery, intestinal delivery, and

Radi Hejazi; Mansoor Amiji

2003-01-01

395

An analysis of Internet content delivery systems  

Microsoft Academic Search

In the span of only a few years, the Internet has experienced an astronomical increase in the use of specialized content delivery systems, such as content delivery networks and peer-to-peer file sharing systems. Therefore, an understanding of content delivery on the lnternet now requires a detailed understanding of how these systems are used in practice.This paper examines content delivery from

Stefan Saroiu; Krishna P. Gummadi; Richard J. Dunn; Steven D. Gribble; Henry M. Levy

2002-01-01

396

Coordination Compounds of Strontium. Syntheses, Characterizations, and Crystal Structures of [Sr(u-ONc)(2)(HONc(4))]2 and Sr(5)(u(4)-O)(u(3)-ONep)(4)(u-ONep)(4)(HONep)(solv)(4) (ONc=O(2)CCH(2)CMe(3));Nep=CH(2)CMe(3); solv=tetrahydrofuran or 1-methyl-imida  

SciTech Connect

The authors have synthesized and characterized two novel Sr compounds: [Sr({mu}-ONc){sub 2}(HONc){sub 4}]{sub 2} (1, ONc = O{sub 2}CCH{sub 2}CMe{sub 3}), and Sr{sub 5}({mu}{sub 4}-O)({mu}{sub 3}-ONep){sub 4}({mu}-ONep){sub 4}(HONep)(solv){sub 4} [ONep = OCH{sub 2}CMe{sub 3}, solv = tetrahydrofuran (THF), 2a; 1-methyl-imidazole (MeIm), (2b)], that demonstrate increased solubility in comparison to the commercially available Sr precursors. The two metal centers of 1 share 4 unidentate bridging {mu}-ONc ligands and complete their octahedral geometry through the coordination of 4 monodentate terminal HONc ligands. The structure arrangement of the central core of 2a and b are identical, wherein 4 octahedral Sr atoms are arranged in a square geometry around a {mu}{sub 4}-O ligand. An additional 7-coordinated Sr atom sits directly atop the {mu}{sub 4}-O to form a square base pyramidal arrangement of the Sr atoms but the apical Sr-O distance is too long to be considered a bond. In solution, compound 1 is disrupted forming a monomer but 2a and b retain their structures.

Boyle, Timothy J.; Tafoya, Cory J.; Scott, Brian L.; Ziller, Joseph W.

1999-07-21

397

43 CFR 418.7 - Who may receive irrigation deliveries.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 false Who may receive irrigation deliveries. 418.7 Section 418.7...Water Delivery § 418.7 Who may receive irrigation deliveries. Project irrigation water deliveries may be made only to...

2014-10-01

398

43 CFR 418.7 - Who may receive irrigation deliveries.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Who may receive irrigation deliveries. 418.7 Section 418.7...Water Delivery § 418.7 Who may receive irrigation deliveries. Project irrigation water deliveries may be made only to...

2013-10-01

399

43 CFR 418.7 - Who may receive irrigation deliveries.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Who may receive irrigation deliveries. 418.7 Section 418.7...Water Delivery § 418.7 Who may receive irrigation deliveries. Project irrigation water deliveries may be made only to...

2011-10-01

400

43 CFR 418.7 - Who may receive irrigation deliveries.  

Code of Federal Regulations, 2012 CFR

... 2011-10-01 true Who may receive irrigation deliveries. 418.7 Section 418.7...Water Delivery § 418.7 Who may receive irrigation deliveries. Project irrigation water deliveries may be made only to...

2012-10-01

401

43 CFR 418.7 - Who may receive irrigation deliveries.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 false Who may receive irrigation deliveries. 418.7 Section 418.7...Water Delivery § 418.7 Who may receive irrigation deliveries. Project irrigation water deliveries may be made only to...

2010-10-01

402

Delivery and Hedging Delivery ties the futures price to the spot price.  

E-print Network

Delivery and Hedging · Delivery ties the futures price to the spot price. · On the delivery date, the settlement price of the futures contract is determined by the spot price. · Hence, when the delivery period is reached, the futures price should be very close to the spot price. · Changes in futures prices usually

Lyuu, Yuh-Dauh

403

Carboxymethyl starch and lecithin complex as matrix for targeted drug delivery: I. Monolithic mesalamine forms for colon delivery.  

PubMed

For drugs expected to act locally in the colon, and for successful treatment, a delivery device is necessary, in order to limit the systemic absorption which decreases effectiveness and causes important side effects. Various delayed release systems are currently commercialized; most of them based on pH-dependent release which is sensitive to gastrointestinal pH variation. This study proposes a novel excipient for colon delivery. This new preparation consists in the complexation between carboxymethyl starch (CMS) and Lecithin (L). As opposed to existing excipients, the new complex is pH-independent, inexpensive, and easy to manufacture and allows a high drug loading. FTIR, X-ray, and SEM structural analysis all support the hypothesis of the formation of a complex. By minor variation of the excipient content within the tablet, it is possible to modulate the release time and delivery at specific sites of the gastrointestinal tract. This study opens the door to a new pH-independent delivery system for mesalamine targeted administration. Our novel formulation fits well with the posology of mesalamine, used in the treatment of Inflammatory Bowel Disease (IBD), which requires repeated administrations (1g orally four times a day) to maintain a good quality of life. PMID:23562535

Mihaela Friciu, Maria; Canh Le, Tien; Ispas-Szabo, Pompilia; Mateescu, Mircea Alexandru

2013-11-01

404

Magnetizable implants for targeted drug delivery  

Microsoft Academic Search

The capability to deliver high effective dosages to specific sites in the human body has become the holy grail of drug delivery research. Drugs with proven effectiveness under in vitro investigation often reach a major roadblock under in vivo testing due to a lack of an effective delivery strategy. In addition, many clinical scenarios require delivery of agents that are

Zachary Graham Forbes

2005-01-01

405

ELI Delivery Consortium AISBL Rue Montoyer 23  

E-print Network

ELI Delivery Consortium AISBL Rue Montoyer 23 1000 Brussels Belgium www.eli-laser.eu Company number: 0538.816.291 ELI Delivery Consortium AISBL Chief Administrative Officer (CAO) ­ Background information and position description Background information on the ELI Delivery

406

Teletex Based Electronic Document Delivery (Project HERMES).  

ERIC Educational Resources Information Center

Project HERMES is characterized by participation of publishers, industrial and public libraries, and national government, and by use of Teletex for both document ordering and delivery. Provision of three facilities (electronic document ordering and delivery, automatic document delivery, electronic mail) to pilot group of 60 organizations is…

Amy, Susan J.

1985-01-01

407

Flexible Delivery of Training. Review of Research.  

ERIC Educational Resources Information Center

Research on flexible delivery of training in Australia since 1990 was reviewed to identify main trends in the delivery of training, the adequacy of research on the topic, and topics that should be addressed in future studies. Selected conclusions of the review are as follows: (1) flexible delivery strategies are valuable in facilitating access to…

Kearns, Peter

408

The determinants of delivery care in Kenya  

Microsoft Academic Search

This paper examines the determinants of place of delivery and childbirth attendant in Kenya based on the 1993 Kenya Demographic and Health Survey data. The analysis utilizes multilevel logistic and multilevel multinomial regression models for the place of delivery and the type of childbirth attendant, respectively. The results show that delivery care in Kenya is determined by a wide range

Monica Magadi; Ian Diamond; Roberto Nascimento Rodrigues

2000-01-01

409

Targeted Retrograde Gene Delivery for Neuronal Protection  

Microsoft Academic Search

The cellular heterogeneity and complex circuitry of the central nervous system make it difficult to achieve precise delivery of experimental and therapeutic agents. We report here an in vivo retrograde gene delivery strategy to target mature projection neurons using adeno-associated virus, a vector with low toxicity and the capacity for long-term gene expression. Viral delivery to axon terminal fields in

Brian K. Kaspar; Dawn Erickson; David Schaffer; Linda Hinh; Fred H. Gage; Daniel A. Peterson

2002-01-01

410

Energetics of homogeneous intermolecular vinyl and allyl carbon-hydrogen bond activation by the 16-electron coordinatively unsaturated organometallic fragment [Tp{prime}Rh(CNCH{sub 2}CMe{sub 3})  

SciTech Connect

Reaction of the complex Tp{prime}Rh(CNneo)(CH{double_bond}CH{sub 2})Cl (neo = CH{sub 2}CMe{sub 3}, Tp{prime} = hydridotris(3,5-dimethylpyrazolyl)borate) with Cp{sub 2}ZrH{sub 2} leads to the formation of Tp{prime}Rh(CNneo)(CH{double_bond}CH{sub 2})H. This complex is also formed upon photolysis of a solution of Tp{prime}Rh(CNneo)(PhN{double_bond}C{double_bond}Nneo) containing ethylene or by thermal reaction of Tp{prime}Rh(CNneo)(c-hexyl)H with ethylene. The vinyl hydride complex rearranges to the more stable {eta}{sup 2}-ethylene complex with a half-life of 8 h at 22 C. Photolysis of a solution of Tp{prime}Rh(CNneo)(PhN{double_bond}C{double_bond}Nneo) in liquid propylene produces the allylic activation product Tp{prime}Rh(CNneo)(CH{sub 2}CH{double_bond}CH{sub 2})H, which rearranges (t{sub 1/2} = 3 days at 11 C) to the {eta}{sup 2}-propylene complex. Allylic activation is also seen with isobutylene, but loss of olefin is observed at 22 C in benzene solution to generate Tp{prime}Rh(CNneo)(Ph)H (t{sub 1/2} = 16.6 h). Photolysis of a tert-butylethylene solution of Tp{prime}Rh(CNneo)(PhN{double_bond}C{double_bond}Nneo) produces the trans vinyl hydride complex, which loses tert-butylethylene to generate Tp{prime}Rh(CNneo)(Ph)H (t{sub 1/2} = 113 days at 22 C). A combination of kinetic selectivity and reductive elimination experiments have allowed for calculation of relative Rh-C bond strengths for both the rhodium allyl and vinyl hydride complexes and for the inclusion of these new data in an analysis of bond strength correlations. The results show that the trend for relative Rh-C bond strengths parallels the trend of hydrocarbon C-H bond strengths, but that differences in M-C bond strengths typically exceed the differences in C-H bond strengths.

Wick, D.D.; Jones, W.D. [Univ. of Rochester, NY (United States). Dept. of Chemistry] [Univ. of Rochester, NY (United States). Dept. of Chemistry

1999-02-15

411

Nanoparticle Delivery Enhancement With Acoustically Activated Microbubbles  

PubMed Central

The application of microbubbles and ultrasound to deliver nanoparticle carriers for drug and gene delivery is an area that has expanded greatly in recent years. Under ultrasound exposure, microbubbles can enhance nanoparticle delivery by increasing cellular and vascular permeability. In this review, the underlying mechanisms of enhanced nanoparticle delivery with ultrasound and microbubbles and various proposed delivery techniques are discussed. Additionally, types of nanoparticles currently being investigated in preclinical studies, as well as the general limitations and benefits of a microbubble-based approach to nanoparticle delivery are reviewed. PMID:23287914

Mullin, Lee B; Phillips, Linsey C; Dayton, Paul A

2013-01-01

412

Dendrimer type bio-reducible polymer for efficient gene delivery.  

PubMed

Arginine-grafted bio-reducible poly(disulfide amine) (ABP) was incorporated into the poly(amido amine) (PAMAM) dendrimer, creating a high molecular weight bio-reducible polymer, PAM-ABP, to overcome the limitations of the low molecular weight ABP. The newly synthesized PAM-ABP was studied to determine its efficacy as a gene delivery carrier. The PAM-ABP demonstrated superior condensing ability for plasmid DNA through the formation of compact nanosized polyplexes. These compact polyplexes enhanced cellular uptake and were less susceptible to reducing agents, resulting in greater transfection efficiency compared to ABP alone. Based on these results, this newly developed PAM-ABP polyplex is a promising delivery system for clinical gene therapy. PMID:22546681

Nam, Hye Yeong; Nam, Kihoon; Lee, Minhyung; Kim, Sung Wan; Bull, David A

2012-06-28

413

Sustained Delivery of Chondroitinase ABC from Hydrogel System.  

PubMed

In the injured spinal cord, chondroitin sulfate proteoglycans (CSPGs) are the principal responsible of axon growth inhibition and they contribute to regenerative failure, promoting glial scar formation. Chondroitinase ABC (chABC) is known for being able to digest proteoglycans, thus degrading glial scar and favoring axonal regrowth. However, its classic administration is invasive, infection-prone and clinically problematic. An agarose-carbomer (AC1) hydrogel, already used in SCI repair strategies, was here investigated as a delivery system capable of an effective chABC administration: the material ability to include chABC within its pores and the possibility to be injected into the target tissue were firstly proved. Subsequently, release kinetic and the maintenance of enzymatic activity were positively assessed: AC1 hydrogel was thus confirmed to be a feasible tool for chABC delivery and a promising device for spinal cord injury topic repair strategies. PMID:24956524

Rossi, Filippo; Veglianese, Pietro; Santoro, Marco; Papa, Simonetta; Rogora, Cristina; Dell'Oro, Valentina; Forloni, Gianluigi; Masi, Maurizio; Perale, Giuseppe

2012-01-01

414

The determinants of delivery care in Kenya.  

PubMed

This paper examines the determinants of place of delivery and childbirth attendant in Kenya based on the 1993 Kenya Demographic and Health Survey data. The analysis utilizes multilevel logistic and multilevel multinomial regression models for the place of delivery and the type of childbirth attendant, respectively. The results show that delivery care in Kenya is determined by a wide range of factors: socioeconomic and cultural factors associated with the individual woman or her household, her demographic status or reproductive behavior relating to a specific birth, as well as availability and accessibility of health services within her community. In addition, a significant variation in delivery care behavior is observed between women and between communities, implying that there are unobserved factors within families and communities that have a significant effect on delivery care. The woman or family effect on delivery care is particularly strong, but varies by distance to the nearest delivery care facility. PMID:12055693

Magadi, M; Diamond, I; Rodrigues, R N

2000-01-01

415

Adhesions following cesarean delivery: a review of their occurrence, consequences and preventative management using adhesion barriers.  

PubMed

The objective of this article is to provide a comprehensive review of the occurrence and consequences of postoperative adhesions following cesarean delivery (CD), and an overview of the published clinical data on prevention in this setting using adhesion barriers. Adhesions occur frequently after CD and the incidence increases with each subsequent CD. Repeat CDs are complicated by adhesions, which increase operating time, time to delivery and risk of bladder injury. Clinical data on the efficacy of adhesion prevention strategies specific to the setting of CD are limited. Two small, nonrandomized studies found that the use of absorbable anti-adhesion barriers was associated with a significant reduction in adhesion formation and a shorter time to delivery at repeat CD, compared with no barrier use. Implications for practice and research are discussed. There is a significant need for well-controlled, randomized clinical studies investigating adhesion prevention in the labor and delivery setting. PMID:24007252

Poole, Judith H

2013-09-01

416

Gelatin Used for Drug Delivery  

NSDL National Science Digital Library

In this activity, learners discover how gelatin can be used as a medium for drug delivery. Learners create colored gelatin and then cut out pieces of the gelatin to simulate medicine (pills). Learners then put their simulated pills in a pan of hot water. Since gelatin is a thermoreversible or cold-setting polymer, gelatin will convert back to a liquid if put in a hot environment. As the gelatin returns to its liquid form, it releases its embedded dye. The dye eventually diffuses completely out of the gelatin which simulates the slow release of a drug from a pill. From this activity, learners learn more about diffusion and drug delivery. Adult supervision recommended.

2012-03-28

417

Gene delivery to dystrophic muscle.  

PubMed

Electroporation is a powerful method for gene delivery to dystrophic muscle in the mdx mouse model of Duchenne muscular dystrophy. Successful transfer of reporter and therapeutic plasmids and antisense oligonucleotides has been demonstrated. However, the efficiency falls with increasing plasmid size. Although it is unlikely that the electrotransfer approach will be useful clinically, it is an important experimental tool, particularly in testing potential immune responses to gene transfer in the absence of vector proteins. PMID:18370219

Wells, Kim E; McMahon, Jill; Foster, Helen; Ferrer, Aurora; Wells, Dominic J

2008-01-01

418

Cyclodextrins in delivery systems: Applications  

PubMed Central

Cyclodextrins (CDs) are a family of cyclic oligosaccharides with a hydrophilic outer surface and a lipophilic central cavity. CD molecules are relatively large with a number of hydrogen donors and acceptors and, thus in general, they do not permeate lipophilic membranes. In the pharmaceutical industry, CDs have mainly been used as complexing agents to increase aqueous solubility of poorly soluble drugs and to increase their bioavailability and stability. CDs are used in pharmaceutical applications for numerous purposes, including improving the bioavailability of drugs. Current CD-based therapeutics is described and possible future applications are discussed. CD-containing polymers are reviewed and their use in drug delivery is presented. Of specific interest is the use of CD-containing polymers to provide unique capabilities for the delivery of nucleic acids. Studies in both humans and animals have shown that CDs can be used to improve drug delivery from almost any type of drug formulation. Currently, there are approximately 30 different pharmaceutical products worldwide containing drug/CD complexes in the market. PMID:21814436

Tiwari, Gaurav; Tiwari, Ruchi; Rai, Awani K.

2010-01-01

419

Vaginal films for drug delivery.  

PubMed

Vaginal dosage forms have been studied in relation to many drugs as the vagina presents several advantages as a site for drug delivery, such as large surface area, rich blood supply, avoidance of the first-pass effect, relatively high permeability to several drugs, and self-insertion. Traditional vaginal dosage forms have been associated with disadvantages such as low residence time and discomfort and have been surpassed by newly designed drug delivery systems, particularly those based on bioadhesive polymers. Vaginal films are solid dosage forms that rapidly dissolve in contact with vaginal fluids and are unlikely to be associated with leakage and messiness. They have been studied for some female genital problems, aiming either contraceptive, antimicrobial, or microbicide effects. Precise and complex processes of manufacturing and characterization are required to achieve successful film formulation. Although scarce, the available user's acceptability studies show promising results. Vaginal films gather a lack of opportunities for both therapeutic and prophylactic actions, and therefore should be considered when designing and developing new vaginal drug delivery systems. PMID:23649325

Machado, Rita M; Palmeira-de-Oliveira, Ana; Martinez-De-Oliveira, José; Palmeira-de-Oliveira, Rita

2013-07-01

420

Peptide vectors for the nonviral delivery of nucleic acids.  

PubMed

Over the past two decades, gene therapy has garnered tremendous attention and is heralded by many as the ultimate cure to treat diseases such as cancer, viral infections, and inherited genetic disorders. However, the therapeutic applications of nucleic acids extend beyond the delivery of double-stranded DNA and subsequent expression of deficient gene products in diseased tissue. Other strategies include antisense oligonucleotides and most notably RNA interference (RNAi). Antisense strategies bear great potential for the treatment of diseases that are caused by misspliced mRNA, and RNAi is a universal and extraordinarily efficient tool to knock down the expression of virtually any gene by specific degradation of the desired target mRNA. However, because of the hurdles associated with effective delivery of nucleic acids across a cell membrane, the initial euphoria surrounding siRNA therapy soon subsided. The ability of oligonucleotides to cross the plasma membrane is hampered by their size and highly negative charge. Viral vectors have long been the gold standard to overcome this barrier, but they are associated with severe immunogenic effects and possible tumorigenesis. Cell-penetrating peptides (CPPs), cationic peptides that can translocate through the cell membrane independent of receptors and can transport cargo including proteins, small organic molecules, nanoparticles, and oligonucleotides, represent a promising class of nonviral delivery vectors. This Account focuses on peptide carrier systems for the cellular delivery of various types of therapeutic nucleic acids with a special emphasis on cell-penetrating peptides. We also emphasize the clinical relevance of this research through examples of promising in vivo studies. Although CPPs are often derived from naturally occurring protein transduction domains, they can also be artificially designed. Because CPPs typically include many positively charged amino acids, those electrostatic interactions facilitate the formation of complexes between the carriers and the oligonucleotides. One drawback of CPP-mediated delivery includes entrapment of the cargo in endosomes because uptake tends to be endocytic: coupling of fatty acids or endosome-disruptive peptides to the CPPs can overcome this problem. CPPs can also lack specificity for a single cell type, which can be addressed through the use of targeting moieties, such as peptide ligands that bind to specific receptors. Researchers have also applied these strategies to cationic carrier systems for nonviral oligonucleotide delivery, such as liposomes or polymers, but CPPs tend to be less cytotoxic than other delivery vehicles. PMID:22455499

Hoyer, Jan; Neundorf, Ines

2012-07-17

421

The perspectives of clients and unqualified allopathic practitioners on the management of delivery care in urban slums, Dhaka, Bangladesh - a mixed method study  

Microsoft Academic Search

BACKGROUND: BRAC is implementing a program to improve maternal and newborn health among the urban poor in the slums of Bangladesh (Mansohi), funded by the Bill & Melinda Gates Foundation. Formative research has demonstrated that unqualified allopathic practitioners (UAPs) are commonly assisting home-delivery. The objective of this study was to explore the role of unqualified allopathic practitioners during home delivery

Tasnuva Wahed; Allisyn C Moran; Mohammad Iqbal

2010-01-01

422

Preparation of a high pH-resistant AAPTS-silica coating and its application to capillary microextraction (CME) of Cu, Zn, Ni, Hg and Cd from biological samples followed by on-line ICP-MS detection  

Microsoft Academic Search

In this work, a novel sol–gel coating of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AAPTS)-silica was prepared for capillary microextraction (CME) of trace Cu, Zn, Ni, Hg and Cd followed by on-line ICP-MS detection. This organic–inorganic hybrid coating was in situ created on the inner walls of fused silica capillary using a sol solution containing tetramethoxysilane (TMOS) as a precursor, AAPTS as a co-precursor, ethanol

Fei Zheng; Bin Hu

2007-01-01

423

On the existence of two different mechanisms of coronal mass ejection formation  

NASA Astrophysics Data System (ADS)

Data from Mark 3 and 4, DPM (Mauna Loa Solar Observatory), and from spacecrafts place-SOHO (LASCO C2, EIT), STEREO (COR1, EUVI) were analyzed. It is demonstrated that the difference between the physical nature of the "impulsive" and the "gradual" CMEs is mainly represented by such parameters as the CME location, velocity and angular size at the moment the CME emerges. The "gradual" CMEs are formed in the corona at 0.1R0 ? h ? 0.7R0 above the limb of the Sun (R0 is the solar radius). They start moving, when their angular size is ? 15-65 degrees (in the heliocentric coordinate system) and their initial velocity V0 ? 0. A probable mechanism for their formation is the eruption of a coronal flux rope from the equilib-rium state. The formation of "impulsive" CMEs appears to begin under the photosphere of the Sun and may be related to ejection of floating magnetic tubes (flux ropes) from the convective zone. At the photospheric level, the radial velocities of such magnetic tubes exceed the local sound velocity and may reach hundreds km/s, while their angular sizes do not exceed ? (1-5)° . Possible ejection of magnetic tubes from the convective zone was theoretically demonstrated earlier.

Eselevich, Victor; Eselevich, Maxim

424

[Mn12O12(O2CMe)12(NO3)4(H2O)4]: facile synthesis of a new type of Mn12 complex.  

PubMed

The title dodecanuclear Mn complex, namely dodeca-?2-acetato-?(24)O:O'-tetraaquatetra-?2-nitrato-?(8)O:O'-tetra-?4-oxido-octa-?3-oxido-tetramanganese(IV)octamanganese(III) nitromethane tetrasolvate, [Mn12(CH3COO)12(NO3)4O12(H2O)4]·4CH3NO2, was synthesized by the reaction of Mn(2+) and Ce(4+) sources in nitromethane with an excess of acetic acid. This compound is distinct from the previously known single-molecule magnet [Mn12O12(O2CMe)16(H2O)4], synthesized by Lis [Acta Cryst. (1980), B36, 2042-2044]. It is the first Mn12-type molecule containing nitrate ligands to be directly synthesized without the use of a preformed cluster. Additionally, this molecule is distinct from all other known Mn12 complexes due to intermolecular hydrogen bonds between the nitrate and water ligands, which give rise to a three-dimensional network. The complex is compared to other known Mn12 molecules in terms of its structural parameters and symmetry. PMID:25734846

Thuijs, Annaliese E; Christou, George; Abboud, Khalil A

2015-03-01

425

The LITA Drill and Sample Delivery System  

NASA Astrophysics Data System (ADS)

The Life in the Atacama (LITA) project has a goal of demonstrating autonomous roving, sample acquisition, delivery and analysis operations in Atacama, Chile. To enable the sample handling requirement, Honeybee Robotics developed a rover-deployed, rotary-percussive, autonomous drill, called the LITA Drill, capable of penetrating to ~80 cm in various formations, capturing and delivering subsurface samples to a 20 cup carousel. The carousel has a built-in capability to press the samples within each cup, and position target cups underneath instruments for analysis. The drill and sample delivery system had to have mass and power requirements consistent with a flight system. The drill weighs 12 kg and uses less than 100 watt of power to penetrate ~80 cm. The LITA Drill auger has been designed with two distinct stages. The lower part has deep and gently sloping flutes for retaining powdered sample, while the upper section has shallow and steep flutes for preventing borehole collapse and for efficient movement of cuttings and fall back material out of the hole. The drill uses the so called 'bite-sampling' approach that is samples are taken in short, 5-10 cm bites. To take the first bite, the drill is lowered onto the ground and upon drilling of the first bite it is then retracted into an auger tube. The auger with the auger tube are then lifted off the ground and positioned next to the carousel. To deposit the sample, the auger is rotated and retracted above the auger tube. The cuttings retained on the flutes are either gravity fed or are brushed off by a passive side brush into the cup. After the sample from the first bite has been deposited, the drill is lowered back into the same hole to take the next bite. This process is repeated until a target depth is reached. The bite sampling is analogous to peck drilling in the machining process where a bit is periodically retracted to clear chips. If there is some fall back into the hole once the auger has cleared the hole, this fall back material will be augered out during auger re-insertion. The next bite will be taken only once the auger has reached the true bottom. In the bite sampling approach the stratigraphy is somewhat preserved since every time the sample is taken, it more or less represents the depth interval in the hole. There is going to be some level of cross contamination due to smearing of cuttings on the flutes against the borehole as the auger is being pulled out, or when formation is very porous and unstable. The goal of the first drill campaign in Atacama in May of 2012 was to demonstrate successful operation of the bite sampling method and to learn about diversity of soils and rocks in the Atacama. In 2013, the sampling system has been integrated onto the CMU Zoe rover and autonomously deployed in Atacama. The drill penetrated various formations and delivered samples to a carousel. When soil was very porous, poor sample recovery was observed. When the soil was dense and cohesive, sample recovery was 100% with little cross contamination. To enable greater sample recovery in loose and unstable formations, the auger diameter will be increased from the current 12.5 mm to 19 mm. Acknowledgements: The project has been funded by the NASA ASTEP program.

Paulsen, G.; Yoon, S.; Zacny, K.; Wettergreeng, D.; Cabrol, N. A.

2013-12-01

426

A Blended Learning Lecture Delivery Model for Large and Diverse Undergraduate Cohorts  

ERIC Educational Resources Information Center

A blended learning model was developed to enhance lecture delivery in a large, diverse introductory psychology unit, introducing the use of an online, personalized learning system for lecture preparation and using lecture time to extend students' understanding. Changes to the assessment included diagnostic, formative and summative online quizzes.…

McKenzie, Wendy A.; Perini, Eloise; Rohlf, Vanessa; Toukhsati, Samia; Conduit, Russell; Sanson, Gordon

2013-01-01

427

Localized drugs delivery hydroxyapatite microspheres for osteoporosis therapy  

NASA Astrophysics Data System (ADS)

This study describes the preparation of hydroxyapatite microspheres for local drugs delivery. The formation of the hydroxyapatite microspheres was initiated by enzymatic decomposition of urea and accomplished by emulsification process (water-in-oil). The microspheres obtained were sintered at 500°C. Scanning electron microscope (SEM) indicated that the microspheres have various porous with random size, which maximizes the surface area. Cytotoxicity was not observed after sintering. Osteoporosis drugs, alendronate and BMP-2, were loaded into HAp microspheres and the releases of both molecules showed sustained releasing profiles.

Lee, J. H.; Ko, I. H.; Jeon, S.-H.; Chae, J. H.; Lee, E. J.; Chang, J. H.

2011-10-01

428

Fiber coupled optical spark delivery system  

DOEpatents

A spark delivery system for generating a spark using a laser beam is provided, the spark delivery system including a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. In addition, the laser delivery assembly includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. In accordance with embodiments of the present invention, the assembly may be used to create a spark in a combustion engine. In accordance with other embodiments of the present invention, a method of using the spark delivery system is provided. In addition, a method of choosing an appropriate fiber for creating a spark using a laser beam is also presented.

Yalin, Azer (Fort Collins, CO); Willson, Bryan (Fort Collins, CO); Defoort, Morgan (Fort Collins, CO)

2008-08-12

429

Physically facilitating drug-delivery systems  

PubMed Central

Facilitated/modulated drug-delivery systems have emerged as a possible solution for delivery of drugs of interest to pre-allocated sites at predetermined doses for predefined periods of time. Over the past decade, the use of different physical methods and mechanisms to mediate drug release and delivery has grown significantly. This emerging area of research has important implications for development of new therapeutic drugs for efficient treatments. This review aims to introduce and describe different modalities of physically facilitating drug-delivery systems that are currently in use for cancer and other diseases therapy. In particular, delivery methods based on ultrasound, electrical, magnetic and photo modulations are highlighted. Current uses and areas of improvement for these different physically facilitating drug-delivery systems are discussed. Furthermore, the main advantages and drawbacks of these technologies reviewed are compared. The review ends with a speculative viewpoint of how research is expected to evolve in the upcoming years. PMID:22485192

Rodriguez-Devora, Jorge I; Ambure, Sunny; Shi, Zhi-Dong; Yuan, Yuyu; Sun, Wei; Xu, Tao

2012-01-01

430

Advances in Lymphatic Imaging and Drug Delivery  

SciTech Connect

Cancer remains the second leading cause of death after heart disease in the US. While metastasized cancers such as breast, prostate, and colon are incurable, before their distant spread, these diseases will have invaded the lymphatic system as a first step in their progression. Hence, proper evaluation of the disease state of the lymphatics which drain a tumor site is crucial to staging and the formation of a treatment plan. Current lymphatic imaging modalities with visible dyes and radionucleotide tracers offer limited sensitivity and poor resolution; however, newer tools using nanocarriers, quantum dots, and magnetic resonance imaging promise to vastly improve the staging of lymphatic spread without needless biopsies. Concurrent with the improvement of lymphatic imaging agents, has been the development of drug carriers that can localize chemotherapy to the lymphatic system, thus improving the treatment of localized disease while minimizing the exposure of healthy organs to cytotoxic drugs. This review will focus on polymeric systems that have been developed for imaging and drug delivery to the lymph system, how these new devices improve upon current technologies, and where further improvement is needed.

Nune, Satish K.; Gunda, Padmaja; Majeti, Bharat K.; Thallapally, Praveen K.; Laird, Forrest M.

2011-09-10

431

Advances in Lymphatic Imaging and Drug Delivery  

PubMed Central

Cancer remains the second leading cause of death after heart disease in the US. While metastasized cancers such as breast, prostate, and colon are incurable, before their distant spread, these diseases will have invaded the lymphatic system as a first step in their progression. Hence, proper evaluation of the disease state of the lymphatics which drain a tumor site is crucial to staging and the formation of a treatment plan. Current lymphatic imaging modalities with visible dyes and radionucleotide tracers offer limited sensitivity and poor resolution; however, newer tools using nanocarriers, quantum dots, and magnetic resonance imaging promise to vastly improve the staging of lymphatic spread without needless biopsies. Concurrent with the improvement of lymphatic imaging agents, has been the development of drug carriers that can localize chemotherapy to the lymphatic system, thus improving the treatment of localized disease while minimizing the exposure of healthy organs to cytotoxic drugs. This review will focus on the use of various nanoparticulate and polymeric systems that have been developed for imaging and drug delivery to the lymph system, how these new devices improve upon current technologies, and where further improvement is needed. PMID:21718728

Nune, Satish K.; Gunda, Padmaja; Majeti, Bharat K.; Thallapally, Praveen K.; Forrest, M. Laird

2011-01-01

432

Ocular Drug Delivery Using Ultrasound  

NASA Astrophysics Data System (ADS)

Our goal was to evaluate ultrasound (US) enhancement of drug delivery through the cornea, and the histological appearance of the cornea, up to 24 h after treatment. The aqueous humor concentration of topically applied sodium fluorescein was determined quantitatively in US-treated and sham rabbit eyes in vivo. Gross and light microscopic examinations were used to observe structural changes in the cornea 0-24 h after US exposure. The increase in the dye concentration in aqueous humor, after the simultaneous application of 880 kHz US and the dye solution (for 5 min), was 2.4 times at 0.19 W/cm2, 3.8 times at 0.34 W/cm2, and 10.6 times at 0.56 W/m2 (p<0.05). The dye delivery was found to increase with increasing US intensity, which corresponded with an increase in cavitation activity. After the separate application of US and the dye solution, the increase in the dye concentration was 3.8 times at 0.56 W/cm2 (p<0.01), while no increase was achieved at 0.19-0.34 W/cm2. The majority of damaged cells were present in the surface layer of the corneal epithelium. Corneal pits, observed in the US-treated epithelium, completely disappeared within 90 min. The application of 880 kHz ultrasound provided enhancement in the delivery of a hydrophilic compound through the cornea while producing minor changes in the corneal epithelium.

Zderic, Vesna; Clark, John I.; Vaezy, Shahram

2005-03-01

433

Sediment delivery after a wildfire  

USGS Publications Warehouse

We use a record of sedimentation a small reservoir within the Cerro Grande burn area, New Mexico, to document postfire delivery of ash, other fine-grained sediment carried in suspension within floods, and coarse-grained sediment transported as bedload over a five-year period. Ash content of sediment layers is estimated using fallout 137Cs as a tracer, and ash concentrations are shown to rapidly decrease through a series of moderate-intensity convective storms in the first rainy season after the fire. Over 90% of the ash was delivered to the reservoir in the first year, and ash concentrations in suspended sediment were negligible after the second year. Delivery of the remainder of the fine sediment also declined rapidly after the first year despite the occurrence of higher-intensity storms in the second year. Fine sediment loads after five years remained significantly above prefire averages. Deposition of coarse-grained sediment was irregular in time and was associated with transport by snowmelt runoff of sediment stored along the upstream channel during short-duration summer floods. Coarse sediment delivery in the first four years was strongly correlated with snowmelt volume, suggesting a transport-limited system with abundant available sediment. Transport rates of coarse sediment declined in the fifth year, consistent with a transition to a more stable channel as the accessible sediment supply was depleted and the channel bed coarsened. Maximum impacts from ash and other fine-grained sediment therefore occurred soon after the fire, whereas the downstream impacts from coarse-grained sediment were attenuated by the more gradual process of bedload sediment transport. ?? 2007 Geological Society of America.

Reneau, S.L.; Katzman, D.; Kuyumjian, G.A.; Lavine, A.; Malmon, D.V.

2007-01-01

434

Local Delivery Methods Into the CNS  

Microsoft Academic Search

The earliest forms of therapeutic drug delivery to the central nervous system (CNS) were systemically based intravenous and\\u000a oral preparations. Despite attempts to increase target concentrations with intraarterial delivery or osmotic opening of the\\u000a blood-brain barrier (BBB), systemic delivery remains hindered by systemic toxicity and the need for extensive drug modification\\u000a for effective (80) BBB penetration. These limitations have provided

Timothy W. Vogel; Jeffrey N. Bruce

435

Microbially triggered drug delivery to the colon  

Microsoft Academic Search

Increasing acceptance of protein- and peptide-based drugs necessitates an investigation into the suitability of various sites for their administration. Colon is being investigated for delivery of such molecules. Colon-specific drug delivery is designed to target drug molecules specifically to this area. Development of site-specific delivery systems may exploit a specific property of the target site for drug activation\\/release. The gastrointestinal

V. R Sinha; Rachna Kumria

2003-01-01

436

Electrically-assisted transdermal delivery of buprenorphine  

Microsoft Academic Search

The objective of this study was to explore the electrically assisted transdermal delivery of buprenorphine. Oral delivery of buprenorphine, a synthetic opiate analgesic, is less efficient due to low absorption and large first-pass metabolism. While transdermal delivery of buprenorphine is expected to avoid the first-pass effect and thereby be more bioavailable, use of electrical enhancement techniques (iontophoresis and\\/or electroporation) could

Sagarika Bose; William R. Ravis; Yuh-Jing Lin; Lei Zhang; Günter A. Hofmann; Ajay K. Banga

2001-01-01

437

Ocular drug delivery systems: An overview  

PubMed Central

The major challenge faced by today’s pharmacologist and formulation scientist is ocular drug delivery. Topical eye drop is the most convenient and patient compliant route of drug administration, especially for the treatment of anterior segment diseases. Delivery of drugs to the targeted ocular tissues is restricted by various precorneal, dynamic and static ocular barriers. Also, therapeutic drug levels are not maintained for longer duration in target tissues. In the past two decades, ocular drug delivery research acceleratedly advanced towards developing a novel, safe and patient compliant formulation and drug delivery devices/techniques, which may surpass these barriers and maintain drug levels in tissues. Anterior segment drug delivery advances are witnessed by modulation of conventional topical solutions with permeation and viscosity enhancers. Also, it includes development of conventional topical formulations such as suspensions, emulsions and ointments. Various nanoformulations have also been introduced for anterior segment ocular drug delivery. On the other hand, for posterior ocular delivery, research has been immensely focused towards development of drug releasing devices and nanoformulations for treating chronic vitreoretinal diseases. These novel devices and/or formulations may help to surpass ocular barriers and associated side effects with conventional topical drops. Also, these novel devices and/or formulations are easy to formulate, no/negligibly irritating, possess high precorneal residence time, sustain the drug release, and enhance ocular bioavailability of therapeutics. An update of current research advancement in ocular drug delivery necessitates and helps drug delivery scientists to modulate their think process and develop novel and safe drug delivery strategies. Current review intends to summarize the existing conventional formulations for ocular delivery and their advancements followed by current nanotechnology based formulation developments. Also, recent developments with other ocular drug delivery strategies employing in situ gels, implants, contact lens and microneedles have been discussed. PMID:25590022

Patel, Ashaben; Cholkar, Kishore; Agrahari, Vibhuti; Mitra, Ashim K

2014-01-01

438

Gene Delivery to the Airway  

PubMed Central

This unit describes generation of and gene transfer to several commonly used airway models. Isolation and transduction of primary airway epithelial cells are first described. Next, the preparation of polarized airway epithelial monolayers is outlined. Transduction of these polarized cells is also described. Methods are presented for generation of tracheal xenografts as well as both ex vivo and in vivo gene transfer to these xenografts. Finally, a method for in vivo gene delivery to the lungs of rodents is included. Methods for evaluating transgene expression are given in the support protocols. PMID:23853081

Keiser, Nicholas W.; Engelhardt, John F.