WorldWideScience

Sample records for 510k bk080002 eprogesa

  1. Premarket Notifications (510(k)s)

    Data.gov (United States)

    U.S. Department of Health & Human Services — Medical device manufacturers are required to submit a premarket notification or 510(k) if they intend to introduce a device into commercial distribution for the...

  2. 78 FR 26786 - 510(k) Device Modifications: Deciding When To Submit a 510(k) for a Change to an Existing Device...

    Science.gov (United States)

    2013-05-08

    ... management in the decision process on whether a medical device modification requires a new 510(k) submission... management into this decision process in a way that ensures appropriate and consistent modification decisions... and resolve the following concerns. 1. Risk Management is a Process--Published risk...

  3. 75 FR 4402 - Strengthening the Center for Devices and Radiological Health's 510(k) Review Process; Public...

    Science.gov (United States)

    2010-01-27

    ... requirement), that the device meets the comparative standard of ``substantial equivalence'' to a ``predicate... about devices that have been cleared for marketing through the 510(k) process. Currently, if a device... different ``intended uses'' and explain your reasoning. b. What are the advantages and disadvantages...

  4. Specific heat of rhenium disulfide in 360-510 K temperature range

    International Nuclear Information System (INIS)

    Isobaric specific heat of rhenium disulfide was measured by the method of differential scanning calorimetry in the range of 360-510 K. Thermodynamic functions of rhenium disulfide were calculated using literature data on standard entropy of the compound for the range of 296.15-600 K. 3 refs., 1 fig., 2 tabs

  5. 75 FR 47307 - Center for Devices and Radiological Health 510(k) Working Group Preliminary Report and...

    Science.gov (United States)

    2010-08-05

    ... HUMAN SERVICES Food and Drug Administration Center for Devices and Radiological Health 510(k) Working... ``Center for Devices and Radiological Health Preliminary Internal Evaluations,'' which is comprised of the... public input on the recommendations discussed in these reports, including the feasibility...

  6. Fixing a 510(K) Loophole: In Support of The Sound Devices Act of 2012

    OpenAIRE

    Ho, Shuenn (Patrick)

    2014-01-01

    The current medical device regulatory system contains a dangerous loophole. While the voluntary recall of a harmful medical device removes it from the market, new devices that claim they are substantially equivalent to the recalled device can still reach the market through the 510(k) premarket notification process. Devices that have gained regulatory clearance in this fashion have caused considerable harm and are much more likely to be recalled for safety reasons as well. The recently propo...

  7. 78 FR 100 - Guidance for Industry and Food and Drug Administration Staff; Refuse To Accept Policy for 510(k)s...

    Science.gov (United States)

    2013-01-02

    ... HUMAN SERVICES Food and Drug Administration Guidance for Industry and Food and Drug Administration Staff; Refuse To Accept Policy for 510(k)s; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is announcing the availability of the...

  8. 21 CFR 880.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act). 880.9 Section 880.9 Food and Drugs FOOD AND DRUG... Food, Drug, and Cosmetic Act (the act). The exemption from the requirement of premarket...

  9. 21 CFR 884.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act). 884.9 Section 884.9 Food and Drugs FOOD AND DRUG..., and Cosmetic Act (the act). The exemption from the requirement of premarket notification (section...

  10. 76 FR 50230 - Center for Devices and Radiological Health 510(k) Clearance Process; Recommendations Proposed in...

    Science.gov (United States)

    2011-08-12

    ... August 5, 2010 (75 FR 47307). After reviewing public comment, CDRH issued a plan of action for... public meeting will be held at the Silver Spring Hilton Hotel, 8727 Colesville Rd., Silver Spring, MD... inhibiting innovation in the medical device industry. 7. FDA should develop procedures that ensure the...

  11. 21 CFR 807.93 - Content and format of a 510(k) statement.

    Science.gov (United States)

    2010-04-01

    ... identifiers, and trade secret and confidential commercial information, as defined in 21 CFR 20.61. (2) The... (CONTINUED) MEDICAL DEVICES ESTABLISHMENT REGISTRATION AND DEVICE LISTING FOR MANUFACTURERS AND INITIAL... patient identifiers, and trade secret and confidential commercial information as defined in § 20.61...

  12. 78 FR 14097 - Pulse Oximeters-Premarket Notification Submissions [510(k)s]; Guidance for Industry and Food and...

    Science.gov (United States)

    2013-03-04

    ... Federal Register of July 19, 2007 (72 FR 39631), FDA announced the availability of the draft guidance... HUMAN SERVICES Food and Drug Administration Pulse Oximeters--Premarket Notification Submissions... availability of the guidance entitled ``Pulse Oximeters--Premarket Notification Submissions .'' This...

  13. 76 FR 81510 - Draft Guidance for Industry and Food and Drug Administration Staff; the 510(k) Program...

    Science.gov (United States)

    2011-12-28

    ... Communication, Outreach and Development (HFM-40), Center for Biologics Evaluation and Research (CBER), Food and...) Paradigm Guidance. FDA recognizes and supports efforts for global convergence of regulatory systems, and...

  14. 21 CFR 866.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... marketed device in that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam... (AIDS), chronic or active hepatitis, tuberculosis, or myocardial infarction or to monitor therapy;...

  15. 21 CFR 876.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... marketed device in that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam... (AIDS), chronic or active hepatitis, tuberculosis, or myocardial infarction or to monitor therapy;...

  16. 21 CFR 892.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  17. 21 CFR 868.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  18. 21 CFR 890.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  19. 21 CFR 864.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... marketed device in that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam... (AIDS), chronic or active hepatitis, tuberculosis, or myocardial infarction or to monitor therapy;...

  20. 21 CFR 886.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  1. 21 CFR 872.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  2. 21 CFR 870.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  3. 21 CFR 862.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... laser beam rather than with a sharpened metal blade, or an in vitro diagnostic device detects or... therapy; (4) For assessing the risk of cardiovascular diseases; (5) For use in diabetes management;...

  4. 21 CFR 882.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  5. 21 CFR 878.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... marketed device in that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam... (AIDS), chronic or active hepatitis, tuberculosis, or myocardial infarction or to monitor therapy;...

  6. 21 CFR 888.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  7. 21 CFR 874.9 - Limitations of exemptions from section 510(k) of the Federal Food, Drug, and Cosmetic Act (the act).

    Science.gov (United States)

    2010-04-01

    ... that generic type of device; e.g., a surgical instrument cuts tissue with a laser beam rather than with... hepatitis, tuberculosis, or myocardial infarction or to monitor therapy; (4) For assessing the risk...

  8. 如何进入美国医疗器械市场--医疗器械企业注册、产品列名与510(K)申请%How to Enter American Medical Device Market

    Institute of Scientific and Technical Information of China (English)

    甄辉

    2003-01-01

    @@ 随着中国加入WTO,中国医疗器械工业与国际间的贸易交往将越来越多.目前国内医疗器械市场上技术含量高的医疗器械以进口居多,但技术含量较低或劳动密集型的设备及易耗品则还是以国内产品为主,而且这类产品在国际医疗器械市场上也有一定竞争力,即使在美国也占有一席之地,但目前这些产品出口美国绝大部分以OEM或转口贸易方式进行,很少打自己的品牌直接进入美国,这对于树立自己的品牌,进一步拓宽市场和获得更大企业利益是不利的,而要以自己的品牌进入美国市场就必须获得美国食品药品管理局(FDA-Food and Drug Administration)的批准认可.本文将简要介绍医疗器械进入美国市场的程序以及如何准备申报资料以获得FDA批准认可等问题.

  9. #DDOD: Establishment Registration & Device Listing

    Data.gov (United States)

    U.S. Department of Health & Human Services — SUMMARY DDOD use case to request means on consolidating multiple data sources (MDR, PMA, 510(k), R&L) in order to build a list of all marketed medical devices....

  10. 78 FR 73553 - Prospective Grant of Exclusive License: Development of Cripto-1 Point of Care (POC) Tests and...

    Science.gov (United States)

    2013-12-06

    ... 510K cleared Point of Care (POC) tests and kits for the purpose of disease state recognition, detection..., pancreas, stomach, gallbladder, breast, lung, endometrium and cervix. Current methodologies of...

  11. MO-F-16A-08: Have An Impact On More Patients From Your Ideas And Inventions

    International Nuclear Information System (INIS)

    Purpose: To inform physicists how to obtain an FDA 510(k) clearance for the innovations they use in their facility and to make those ideas widely available to patients throughout the U.S. Methods: Give advice from 20 years experience of assisting in well over 100 successful 510(k) clearances. Results: Learn how to develop a 510(k) submission. Conclusion: Many physicists, physicians and radiation therapists have developed innovations that that are helpful to the patients in their institution. But, many of these innovations deserve to be made available to patients throughout the United States. The author, a Certified Radiological Physicist and former FDA employee, has consulted for over twenty years for inventors, start-ups and established medical device manufacturers to bring new devices to market in the U.S. and to assist them to established FDA compliant quality systems for manufacturing. In this presentation the audience will learn the important points for deciding to go forward with obtaining a Premarket Notification clearance [also known as a 510(k) clearance] to legally market a medical device in the United States. The FDA has published guidelines for submitting a 510(k) application. However, the methods used to efficiently develop the documentation for submission and to obtain clearance in the shortest possible time comes from the author's experience in assisting well over one hundred successful 510(k) clearances.Whether you want to start your own company or to market your idea to an established medical device manufacturer, the value of your innovation increases with a documented 510(k) clearance from FDA

  12. 77 FR 48159 - Draft Guidance for Industry and Food and Drug Administration Staff; Refuse To Accept Policy for...

    Science.gov (United States)

    2012-08-13

    ... HUMAN SERVICES Food and Drug Administration Draft Guidance for Industry and Food and Drug Administration Staff; Refuse To Accept Policy for 510(k)s; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is announcing the availability of...

  13. 78 FR 5186 - Clinical Flow Cytometry in Hematologic Malignancies; Public Workshop; Request for Comments

    Science.gov (United States)

    2013-01-24

    ... monoclonal antibodies and flow cytometry contributed to the automation of lymphocyte subset analysis. Flow cytometric lymphocyte subset analysis was initially used to immunophenotype hematological malignancies; however, the HIV epidemic led to a large number of 510(k) submissions addressing use for HIV...

  14. 78 FR 14013 - Medical Devices; Exemption From Premarket Notification; Class II Devices; Wheelchair Elevator

    Science.gov (United States)

    2013-03-04

    ..., 1998 (63 FR 3142). Section 510(m)(2) of the FD&C Act provides that FDA may exempt a device from....) In the Federal Register of June 1, 2012 (77 FR 32644), FDA published a notice announcing that this... criteria laid out in the Class II 510(k) Exemption Guidance and in 63 FR 3142, and agrees they weigh...

  15. 21 CFR 870.3450 - Vascular graft prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vascular graft prosthesis. 870.3450 Section 870... prosthesis. (a) Identification. A vascular graft prosthesis is an implanted device intended to repair... Prostheses 510(k) Submissions.”...

  16. Structural studies of disordered Mg2NiH4 formed by mechanical grinding

    DEFF Research Database (Denmark)

    Rönnebro, Ewa; Jensen, Jens Oluf; Noréus, Dag;

    1999-01-01

    The low temperature phase of Mg2NiH4 was mechanically ground in argon atmosphere. The ordered monoclinic structure was destroyed to form the disordered cubic structure, previously only found above 510 K. With a Guinier-Hagg X-ray camera the cell parameter was determined to be a=6.492(3) Angstrom...

  17. Dosimetric characteristics of ultraviolet and x-ray-irradiated KBr:Eu2+ thermoluminescence crystals

    International Nuclear Information System (INIS)

    Thermoluminescence (TL) characteristics of KBr:Eu2+ (150 ppm) previously exposed to ultraviolet (UV) light (200 endash 300 nm) and x-ray radiation at room temperature have been determined. The TL glow curve of UV-irradiated samples is composed of six peaks located at 337, 384, 402, 435, 475, and 510 K. The TL glow curves of x-irradiated samples show mainly a TL peak around 384 K. The TL intensities of UV-irradiated (402 and 510 K glow peaks) and x-irradiated specimens present a linear dependence as a function of radiation dose as well as fading stability 300 s after irradiation. These results further enhance the possibilities of using europium-doped materials in nonionizing (actinic region) and ionizing radiation detection and dosimetry applications. copyright 1996 American Institute of Physics

  18. Dosimetric characteristics of ultraviolet and x-ray-irradiated KBr:Eu{sup 2+} thermoluminescence crystals

    Energy Technology Data Exchange (ETDEWEB)

    Melendrez, R.; Perez-Salas, R. [Programa de Posgrado en Fisica de Materiales, Centro de Investigacion, Cientifica y de Educacion Superior de Ensenada, Apartado Postal 2681, Ensenada, Baja California, 22800 (Mexico); Aceves, R.; Piters, T.M.; Barboza-Flores, M. [Centro de Investigacion en Fisica, Universidad de Sonora, Apartado Postal 5-088, Hermosillo, Sonora, 83190 (Mexico)

    1996-08-01

    Thermoluminescence (TL) characteristics of KBr:Eu{sup 2+} (150 ppm) previously exposed to ultraviolet (UV) light (200{endash}300 nm) and x-ray radiation at room temperature have been determined. The TL glow curve of UV-irradiated samples is composed of six peaks located at 337, 384, 402, 435, 475, and 510 K. The TL glow curves of x-irradiated samples show mainly a TL peak around 384 K. The TL intensities of UV-irradiated (402 and 510 K glow peaks) and x-irradiated specimens present a linear dependence as a function of radiation dose as well as fading stability 300 s after irradiation. These results further enhance the possibilities of using europium-doped materials in nonionizing (actinic region) and ionizing radiation detection and dosimetry applications. {copyright} {ital 1996 American Institute of Physics.}

  19. 美国FDA对医疗器械标识的要求%FDA Labeling Requirements for Medical Devices

    Institute of Scientific and Technical Information of China (English)

    马琳榕; 甄辉

    2006-01-01

    分析了标识对医疗器械的重要性,介绍了美国FDA对医疗器械标识的要求,包括通用要求以及对体外诊断试剂产品、临床研究用器械、510(K)、GMP、以及辐射类器械的特定要求.

  20. Microsources of intense fusion in focused discharges of plasma focus

    International Nuclear Information System (INIS)

    High nuclear reactivity within submillimetric domains in the space structure of the pinch of focused discharges has been reported since many years. Now the authors summarize and compare new and previously published data from our experiments which describe the emission of D+ beams and the occurrence of nuclear fusion reactions within submillimetric domains of plasma focus (PF) discharges for W = 5--10 kJ PF machines operating in the neutron optimized mode

  1. Blood trauma testing for mechanical circulatory support devices.

    Science.gov (United States)

    Giridharan, Guruprasad A; Sobieski, Michael A; Ising, Mickey; Slaughter, Mark S; Koenig, Steven C

    2011-01-01

    Preclinical hemolysis testing is a critical requirement toward demonstrating device safety for U.S. Food and Drug Administration (FDA) 510(k) approval of mechanical circulatory support devices (MCSD). FDA and ASTM (formerly known as the American Society for Testing and Materials) have published guidelines to assist industry with developing study protocols. However, there can be significant variability in experimental procedures, study design, and reporting of data that makes comparison of test and predicate devices a challenge. To overcome these limitations, we present a hemolysis testing protocol developed to enable standardization of hemolysis testing while adhering to FDA and ASTM guidelines. Static mock flow loops primed with fresh bovine blood (600 mL, Hematocrit = 27±5%, heparin titrated for ACT >300 sec) from a single-source donor were created as a platform for investigating test and predicate devices. MCSD differential pressure and temperature were maintained at 80 mmHg and 25°±2° C. Blood samples (3 ml) were collected at 0, 5, 90, 180, 270, 360 minutes to measure CBC and plasma free hemoglobin. This protocol led to 510(k) approval of two adult MCSD and has been used to test novel cannulae and a pediatric MCSD. Standardization of hemolysis testing procedures and transparency of results may enable better blood trauma characterization of MCS devices to facilitate the FDA 510(k) and PMA submission processes and improve clinical outcomes. PMID:21812617

  2. US definitions, current use, and FDA stance on use of platelet-rich plasma in sports medicine.

    Science.gov (United States)

    Beitzel, Knut; Allen, Donald; Apostolakos, John; Russell, Ryan P; McCarthy, Mary Beth; Gallo, Gregory J; Cote, Mark P; Mazzocca, Augustus D

    2015-02-01

    With increased utilization of platelet-rich plasma (PRP), it is important for clinicians to understand the United States, the Food and Drug Administration (FDA) regulatory role and stance on PRP. Blood products such as PRP fall under the prevue of FDA's Center for Biologics Evaluation and Research (CBER). CBER is responsible for regulating human cells, tissues, and cellular and tissue-based products. The regulatory process for these products is described in the FDA's 21 CFR 1271 of the Code of Regulations. Under these regulations, certain products including blood products such as PRP are exempt and therefore do not follow the FDA's traditional regulatory pathway that includes animal studies and clinical trials. The 510(k) application is the pathway used to bring PRP preparation systems to the market. The 510(k) application allows devices that are "substantially equivalent" to a currently marketed device to come to the market. There are numerous PRP preparation systems on the market today with FDA clearance; however, nearly all of these systems have 510(k) clearance for producing platelet-rich preparations intended to be used to mix with bone graft materials to enhance bone graft handling properties in orthopedic practices. The use of PRP outside this setting, for example, an office injection, would be considered "off label." Clinicians are free to use a product off-label as long as certain responsibilities are met. Per CBER, when the intent is the practice of medicine, clinicians "have the responsibility to be well informed about the product, to base its use on firm scientific rationale and on sound medical evidence, and to maintain records of the product's use and effects." Finally, despite PRP being exempted, the language in 21 CFR 1271 has caused some recent concern over activated PRP; however to date, the FDA has not attempted to regulate activated PRP. Clinicians using activated PRP should be mindful of these concerns and continued to stay informed. PMID

  3. Innovating in the medical device industry - challenges & opportunities ESB 2015 translational research symposium.

    Science.gov (United States)

    Bayon, Y; Bohner, M; Eglin, D; Procter, P; Richards, R G; Weber, J; Zeugolis, D I

    2016-09-01

    The European Society for Biomaterials 2015 Translational Research Symposium focused on 'Innovating in the Medical Device Industry - Challenges & Opportunities' from different perspectives, i.e., from a non-profit research organisation to a syndicate of small and medium-sized companies and large companies. Lecturers from regulatory consultants, industry and research institutions described the innovation process and regulatory processes (e.g., 510K, PMA, combination product) towards market approval. The aim of the present article is to summarise and explain the main statements made during the symposium, in terms of challenges and opportunities for medical device industries, in a constantly changing customer and regulatory environment. PMID:27552808

  4. Spin-lattice coupling in multiferroic Pb(Fe1/2Nb1/2)O3 thin films

    OpenAIRE

    Peng, W.; Lemée, N.; Karkut, M.; Dkhil, B.; Shvartsman, V. V.; Borisov, P.; Kleemann, W.; Holc, J.; Kosec, M.; Blinc, R.

    2009-01-01

    We have made magnetization and x-ray diffraction measurements on an epitaxial Pb(Fe1/2Nb1/2)O3 200 nm film. From the temperature dependence of the out-of-plane lattice parameter we can assign a Burns' temperature at Td ~ 640 K, a temperature at T* ~ 510 K, related to the appearance of static polar nanoregions, and an anomaly occurring at 200 K. The latter is precisely the N\\'eel temperature TN determined from magnetization and points to spin-lattice coupling at TN ~ 200 K. We also observe "we...

  5. Medicolegal issues surrounding devices and mesh for surgical treatment of prolapse and incontinence.

    Science.gov (United States)

    Nosti, Patrick A; Iglesia, Cheryl B

    2013-06-01

    Legal issues related to vaginal mesh devices for prolapse and incontinence include abnormal injury and inadequate informed consent. Although vaginal mesh devices are currently cleared through the 510(k) process, new developments at the US Food and Drug Administration requiring additional postmarket studies (522 studies) for transvaginal mesh for prolapse and mini-suburethral synthetic slings have been issued to ensure product safety and effectiveness. New initiatives including unique device identification numbers and the Pelvic Floor Disorders Registry have been developed to improve surveillance throughout the total product/device life cycle.

  6. Hardware/Software Issues for Video Guidance Systems: The Coreco Frame Grabber

    Science.gov (United States)

    Bales, John W.

    1996-01-01

    The F64 frame grabber is a high performance video image acquisition and processing board utilizing the TMS320C40 and TMS34020 processors. The hardware is designed for the ISA 16 bit bus and supports multiple digital or analog cameras. It has an acquisition rate of 40 million pixels per second, with a variable sampling frequency of 510 kHz to MO MHz. The board has a 4MB frame buffer memory expandable to 32 MB, and has a simultaneous acquisition and processing capability. It supports both VGA and RGB displays, and accepts all analog and digital video input standards.

  7. Impact of Organic and Inorganic Fertilizers Application on the Phytochemical and Antioxidant Activity of Kacip Fatimah (Labisia pumila Benth)

    OpenAIRE

    Ehsan Karimi; Ali Ghasemzadeh; Jaafar, Hawa Z. E.; Mohd Hafiz Ibrahim

    2013-01-01

    A study was conducted to compare secondary metabolites and antioxidant activity of Labisia pumila Benth (Kacip Fatimah) in response to two sources of fertilizer [i.e., organic (chicken dung; 10% N:10% P2O5:10% K2O) and inorganic fertilizer (NPK green; 15% N, 15% P2O5, 15% K2O)] under different N rates of 0, 90, 180 and 270 kg N/ha. The experiment was arranged in a randomized complete block design replicated three times. At the end of 15 weeks, it was observed that the application of organic f...

  8. Improvement of hygienic quality of white ginseng powders by {gamma}-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Han-Ok; Byun, Myung-Woo; Kang, Il-Jun; Youk, Hong-Sun [Korea Atomic Energy Research Inst., Taejon (Korea, Republic of); Kwon, Joong-Ho

    1994-12-01

    For the purpose of improving hygienic quality of white ginseng powders, the comparative effects of ethylene oxide (EO) fumigation and {gamma}-irradiation (5-10 kGy) on the sterilization, physiochemical properties and organoleptic quality were investigated. EO fumigation and {gamma}-irradiation (5-10 kGy) completely eliminated the microorganisms contaminating in white ginseng powder. There was no growth of microorganisms after 7 months storage at 30degC and different relative humidities. In the physiochemical properties, ginseng saponins were considerably resistant to {gamma}-irradiation (less than 10 kGy) and commercial EO fumigation, while sulfur-containing amino acids, reducing sugar and acidity were significantly changed by EO fumigation. EO residues were 570 ppm in the samples taken immediately after deaeration and 170 ppm in the stored samples of 8 days at 30degC, respectively. Ethylene chlorohydrin and ethylene glycol residues as the secondary products of EO were 9,595 ppm immediately after deaeration and 221 ppm in the stored samples of 3 months at 30degC. (author).

  9. Improvement of hygienic quality of white ginseng powders by γ-irradiation

    International Nuclear Information System (INIS)

    For the purpose of improving hygienic quality of white ginseng powders, the comparative effects of ethylene oxide (EO) fumigation and γ-irradiation (5-10 kGy) on the sterilization, physiochemical properties and organoleptic quality were investigated. EO fumigation and γ-irradiation (5-10 kGy) completely eliminated the microorganisms contaminating in white ginseng powder. There was no growth of microorganisms after 7 months storage at 30degC and different relative humidities. In the physiochemical properties, ginseng saponins were considerably resistant to γ-irradiation (less than 10 kGy) and commercial EO fumigation, while sulfur-containing amino acids, reducing sugar and acidity were significantly changed by EO fumigation. EO residues were 570 ppm in the samples taken immediately after deaeration and 170 ppm in the stored samples of 8 days at 30degC, respectively. Ethylene chlorohydrin and ethylene glycol residues as the secondary products of EO were 9,595 ppm immediately after deaeration and 221 ppm in the stored samples of 3 months at 30degC. (author)

  10. Design of a Modular 5-kW Power Processing Unit for the Next-Generation 40-cm Ion Engine

    Science.gov (United States)

    Pinero, Luis R.; Bond, Thomas; Okada, Don; Pyter, Janusz; Wiseman, Steve

    2002-01-01

    NASA Glenn Research Center is developing a 5/10-kW ion engine for a broad range of mission applications. Simultaneously, a 5-kW breadboard poster processing unit is being designed and fabricated. The design includes a beam supply consisting of four 1.1 kW power modules connected in parallel, equally sharing the output current. A novel phase-shifted/pulse-width-modulated dual full-bridge topology was chosen for its soft-switching characteristics. The proposed modular approach allows scalability to higher powers as well as the possibility of implementing an N+1 redundant beam supply. Efficiencies in excess of 96% were measured during testing of a breadboard beam power module. A specific mass of 3.0 kg/kW is expected for a flight PRO. This represents a 50% reduction from the state of the art NSTAR power processor.

  11. 福特GT:压力及动力

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    福特GT强大吗?没人会怀疑超过370kW的轰鸣不为你带来纯粹的美国肌肉式的感受。但是有些人不满足于原装动力,为这款5.4L的发动机装上机械增压,并鼓作气的将功率升华到510kW的境界。改装工作由Geiger、Cars主持完成,成效显著。百公里加速3.5s,四分之一英里冲刺仅需10.9s。这无疑是款完美的速度机器。

  12. Patient and healthcare professional satisfaction with a new, high accuracy blood glucose meter with color range indicator and wireless connectivity.

    Science.gov (United States)

    Katz, Laurence B; Grady, Mike; Stewart, Lorna; Cameron, Hilary

    2016-07-01

    Accurate self-monitoring of blood glucose is a key component of effective self-management of glycemic control. The OneTouch VerioFlex(™) (OTVF) blood glucose monitoring system (BGMS) was evaluated for accuracy in a clinical setting. Patients also used OTVF for a 1-wk trial period and reported their level of satisfaction with meter features. In a separate study, healthcare professionals used an on-line simulator of the BGMS and answered questions about its potential utility to their patients. OTVF was accurate over a wide glucose range and met lay user and system accuracy blood glucose standards described in ISO15197:2013 as well as the accuracy requirements to fulfill US FDA expectations for 510(k) clearance of BGMS. Patients and healthcare professionals felt the features of OTVF, which has the capability to connect wirelessly to mobile devices and interact wirelessly with diabetes management software, could provide significant benefits to them or their patients. PMID:27232211

  13. Design of a near-IR coherent lidar for high spatial and velocity resolution wind measurement

    Science.gov (United States)

    Grund, Christian J.; Post, Madison J.

    1992-01-01

    A coherent Doppler lidar based on a CW diode-pumped, injection seeded, Th:YAG laser operating at approx. 2.02 microns is currently under development. This system is optimized for measurements of boundary layer winds with high spatial, temporal, and velocity resolution. Initially, the system will run alongside a new high repetition rate (5-10 kHz) CO2 mini-Master Oscillator Power Amplifier (mini-MOPA) Doppler lidar, which will provide simultaneous range-resolved Differential Absorption Lidar (DIAL) water vapor measurements. Water vapor DIAL operation of the 2 micron system is being considered as a future option. The anticipated specifications and the preliminary design are discussed.

  14. Xenon ion propulsion for orbit transfer

    Science.gov (United States)

    Rawlin, V. K.; Patterson, M. J.; Gruber, R. P.

    1990-01-01

    The status of critical ion propulsion system elements is reviewed. Electron bombardment ion thrusters for primary propulsion have evolved to operate on xenon in the 5-10 kW power range. Thruster efficiencies of 0.7 and specific impulse values of 4000 s have been documented. The baseline thruster currently under development by NASA LeRC includes ring-cusp magnetic field plasma containment and dished two-grid ion optics. Based on past experience and demonstrated simplifications, power processors for these thrusters should have approximately 500 parts, a mass of 40 kg, and an efficiency near 0.94. Thrust vector control, via individual thruster gimbals, is a mature technology. High pressure, gaseous xenon propellant storage and control schemes, using flight qualified hardware, result in propellant tankage fractions between 0.1 and 0.2. In-space and ground integration testing has demonstrated that ion propulsion systems can be successfully integrated with their host spacecraft.

  15. Internal photoradiation effect. Radiation-induced luminescence and its influence on radiation processes

    International Nuclear Information System (INIS)

    Effect of radiation-induced luminescence on stabilization and reactions of intermediate charged particles in polymers in course of radiolysis is experimentally and theoretically investigated. The subjects of inquiry are polystyrene and polyvinyl alcohol films. Irradiation was carried out by 60Co γ-quanta in liquid nitrogen up to 5-10 kGy, the dose rate being approximately 5 Gy/s. It is stated that polymer luminescence results in decrease of concentration of stabilized charged particles, determines inequality of their distribution with respect to polymer volume and causes photochemical reactions. Contribution of photoradiation processes to radiation changes of material properties is defined by molecule properties, irradiation conditions, form and size of irradiated sample

  16. Quantitative mid-infrared spectra of allene and propyne from room to high temperatures

    KAUST Repository

    Es-sebbar, Et-touhami

    2014-11-01

    Allene (a-C3H4; CH2CCH2) and propyne (p-C3H4; CH3C2H) have attracted much interest because of their relevance to the photochemistry in astrophysical environments as well as in combustion processes. Both allene and propyne have strong absorption in the infrared region. In the present work, infrared spectra of a-C3H4 and p-C3H4 are measured in the gas phase at temperatures ranging from 296 to 510 K. The spectra are measured over the 580-3400 cm-1 spectral region at resolutions of 0.08 and 0.25 cm-1 using Fourier Transform Infrared spectroscopy. Absolute integrated intensities of the main infrared bands are determined at room temperature and compared with values derived from literature for both molecules. Integrated band intensities are also determined as a function of temperature in various spectral regions.

  17. An HTS X-band DC SQUID based amplifier: Modeling and development concepts

    DEFF Research Database (Denmark)

    Prokopenko, G.V.; Shitov, S.V.; Borisenko, I.V.;

    2003-01-01

    on a combination of single-layer slot and coplanar lines forming novel input and output circuits. The following parameters (per stage) are obtained via simulation for central frequency 11 GHz: bandwidth 0.5-1 GHz, power gain 11-12 dB, noise temperature 5-10 K. A saturation product as high as 500-1000 K......We present an X-band amplifier concept based on a HTS grain boundary dc SQUID, which allow for extended dynamic range for use with SIS mixers, e.g., as a buffer amplifier in front of an RSFQ ADC, or possibly for satellite and cellular phone communications. The proposed rf design is based......(.)GHz is estimated for a characteristic voltage of 1-2 mV. The realization of these parameters makes HTS SQA competitive with existing coolable HEMT-amplifiers for radio astronomy and satellite communication....

  18. Studies on safety and efficacy of gamma-irradiated ginseng -Development of irradiation techniques for quality improvement of ginseng products-

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Han Ok; Byun, Myung Woo; Cho, Sung Kee; Kand, Il Joon; Yook, Hong Sun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-02-01

    Gamma irradiation was applied to red ginseng powder for improving microbiological and physicochemical quality. Irradiation at 5-10 kGy was effective for sterilizing all contaminated microorganisms of red ginseng powder. At the dose levels, major physicochemical properties (saponin, amino acids, sugars, proximate composition, color, pH, acidity, hydrogen donating activity, fatty acids and minerals) were not changed by gamma irradiation upto 10 kGy. Based upon the results, it is concluded that gamma irradiation can effectively improve the microbiological quality of red ginseng powders without significant unfavorable changes. Therefore, it is suggested that irradiation technology is a viable alternative method to other sanitary process containing chemical fumigant and will be useful for the improvement of the quality of red ginseng powders and their products. 5 figs, 18 tabs, 92 refs. (Author).

  19. Ferromagnetism and crystalline electric field effects in cubic UX2Zn20 (X=Co, Rh, Ir)

    Science.gov (United States)

    Bauer, E. D.; Thompson, J. D.; Sarrao, J. L.; Hundley, M. F.

    2007-03-01

    The physical properties of a new family of cubic UX2Zn20 (X=Co, Rh, Ir) heavy-fermion compounds are presented. Both UCo2Zn20 and URh2Zn20 show peaks in specific heat and magnetic susceptibility at ˜5-10 K suggesting the presence of crystalline electric field (CEF) effects in these materials, i.e., a localized 5f2 configuration of uranium. UIr2Zn20 exhibits a first-order ferromagnetic transition at Tc=2.1 K with a saturation moment μsat=0.4 μB at 2 K indicating itinerant ferromagnetism. All compounds in this series are heavy-fermion materials with enhanced electronic specific heat coefficients γ˜100-450 mJ/mol K2.

  20. Studies on safety and efficacy of gamma-irradiated ginseng -Development of irradiation techniques for quality improvement of ginseng products-

    International Nuclear Information System (INIS)

    Gamma irradiation was applied to red ginseng powder for improving microbiological and physicochemical quality. Irradiation at 5-10 kGy was effective for sterilizing all contaminated microorganisms of red ginseng powder. At the dose levels, major physicochemical properties (saponin, amino acids, sugars, proximate composition, color, pH, acidity, hydrogen donating activity, fatty acids and minerals) were not changed by gamma irradiation upto 10 kGy. Based upon the results, it is concluded that gamma irradiation can effectively improve the microbiological quality of red ginseng powders without significant unfavorable changes. Therefore, it is suggested that irradiation technology is a viable alternative method to other sanitary process containing chemical fumigant and will be useful for the improvement of the quality of red ginseng powders and their products. 5 figs, 18 tabs, 92 refs. (Author)

  1. Effect of explant treatment with gamma-rays, EMS and SA on somatic tissue culture in rice

    International Nuclear Information System (INIS)

    Dry seeds of two rice cultivars were treated with gamma-rays (0-40 kR), EMS (0-0.4M) and SA (0-4mM) and then inoculated in N6 medium containing 0.5mg/l 2,4-D, 4mg/l NAA and 2mg/l 6-BA to induce callus.Growth and differentiation' of the callus treated rice seeds were observed in subsequent subcultures.Decreased callus induction percentages were observed in treatments with gamma-rays, EMS and SA, but the mutagenic treatments did not reduce the mean weight of primary calli except that the seeds were irradiated with gamma-rays.Moreover, up to 3-fold increase in callus growth rate was shown after treatments of the three mu-tagenic agents.Higher proportion of calli with green spots or small shoots was also seen in one cultivar treated with the three mutagens.Signif icant increase in plant regeneration capacity was found in 60-day-old calli derived from gamma-rays or EMS-treated rice seeds in one cultivar.The results suggested that the following dose or concentration can be used for explant treatment in indica rice before culture, gamma-rays.5-10kR, EMS.<0.2M and SA:2-4mM

  2. Accuracy of the Lifebox pulse oximeter during hypoxia in healthy volunteers.

    Science.gov (United States)

    Dubowitz, G; Breyer, K; Lipnick, M; Sall, J W; Feiner, J; Ikeda, K; MacLeod, D B; Bickler, P E

    2013-12-01

    Pulse oximetry is a standard of care during anaesthesia in high-income countries. However, 70% of operating environments in low- and middle-income countries have no pulse oximeter. The 'Lifebox' oximetry project set out to bridge this gap with an inexpensive oximeter meeting CE (European Conformity) and ISO (International Organization for Standardization) standards. To date, there are no performance-specific accuracy data on this instrument. The aim of this study was to establish whether the Lifebox pulse oximeter provides clinically reliable haemoglobin oxygen saturation (Sp O2 ) readings meeting USA Food and Drug Administration 510(k) standards. Using healthy volunteers, inspired oxygen fraction was adjusted to produce arterial haemoglobin oxygen saturation (Sa O2 ) readings between 71% and 100% measured with a multi-wavelength oximeter. Lifebox accuracy was expressed using bias (Sp O2 - Sa O2 ), precision (SD of the bias) and the root mean square error (Arms). Simultaneous readings of Sa O2 and Sp O2 in 57 subjects showed a mean (SD) bias of -0.41% (2.28%) and Arms 2.31%. The Lifebox pulse oximeter meets current USA Food and Drug Administration standards for accuracy, thus representing an inexpensive solution for patient monitoring without compromising standards.

  3. NeutroPhase® in chronic non-healing wounds

    Science.gov (United States)

    Crew, John; Varilla, Randell; Rocas, Thomas Allandale; Debabov, Dmitri; Wang, Lu; Najafi, Azar; Rani, Suriani Abdul; Najafi, Ramin (Ron); Anderson, Mark

    2012-01-01

    Chronic non-healing wounds, such as venous stasis ulcers, diabetic ulcers, and pressure ulcers are serious unmet medical needs that affect a patient’s morbidity and mortality. Common pathogens observed in chronic non-healing wounds are Staphylococcus including MRSA, Pseudomonas, Enterobacter, Stenotrophomonas, and Serratia spp. Topical and systemically administered antibiotics do not adequately decrease the level of bacteria or the associated biofilm in chronic granulating wounds and the use of sub-lethal concentrations of antibiotics can lead to resistant phenotypes. Furthermore, topical antiseptics may not be fully effective and can actually impede wound healing. We show 5 representative examples from our more than 30 clinical case studies using NeutroPhase® as an irrigation solution with chronic non-healing wounds with and without the technique of negative pressure wound therapy (NPWT). NeutroPhase® is pure 0.01% hypochlorous acid (i.e. >97% relative molar distribution of active chlorine species as HOCl) in a 0.9% saline solution at pH 4-5 and is stored in glass containers. NovaBay has three FDA cleared 510(k)s. Patients showed a profound improvement and marked accelerated rates of wound healing using NeutroPhase® with and without NPWT. NeutroPhase® was non-toxic to living tissues. PMID:23272294

  4. NeutroPhase(®) in chronic non-healing wounds.

    Science.gov (United States)

    Crew, John; Varilla, Randell; Rocas, Thomas Allandale; Debabov, Dmitri; Wang, Lu; Najafi, Azar; Rani, Suriani Abdul; Najafi, Ramin Ron; Anderson, Mark

    2012-01-01

    Chronic non-healing wounds, such as venous stasis ulcers, diabetic ulcers, and pressure ulcers are serious unmet medical needs that affect a patient's morbidity and mortality. Common pathogens observed in chronic non-healing wounds are Staphylococcus including MRSA, Pseudomonas, Enterobacter, Stenotrophomonas, and Serratia spp. Topical and systemically administered antibiotics do not adequately decrease the level of bacteria or the associated biofilm in chronic granulating wounds and the use of sub-lethal concentrations of antibiotics can lead to resistant phenotypes. Furthermore, topical antiseptics may not be fully effective and can actually impede wound healing. We show 5 representative examples from our more than 30 clinical case studies using NeutroPhase(®) as an irrigation solution with chronic non-healing wounds with and without the technique of negative pressure wound therapy (NPWT). NeutroPhase(®) is pure 0.01% hypochlorous acid (i.e. >97% relative molar distribution of active chlorine species as HOCl) in a 0.9% saline solution at pH 4-5 and is stored in glass containers. NovaBay has three FDA cleared 510(k)s. Patients showed a profound improvement and marked accelerated rates of wound healing using NeutroPhase(®) with and without NPWT. NeutroPhase(®) was non-toxic to living tissues. PMID:23272294

  5. Experimental investigation of plasma relaxation using a compact coaxial magnetized plasma gun in a background plasma

    Science.gov (United States)

    Zhang, Yue; Lynn, Alan; Gilmore, Mark; Hsu, Scott; University of New Mexico Collaboration; Los Alamos National Laboratory Collaboration

    2013-10-01

    A compact coaxial plasma gun is employed for experimental studies of plasma relaxation in a low density background plasma. Experiments are being conducted in the linear HelCat device at UNM. These studies will advance the knowledge of basic plasma physics in the areas of magnetic relaxation and space and astrophysical plasmas, including the evolution of active galactic jets/radio lobes within the intergalactic medium. The gun is powered by a 120pF ignitron-switched capacitor bank which is operated in a range of 5-10 kV and ~100 kA. Multiple diagnostics are employed to investigate plasma relaxation process. Magnetized Argon plasma bubbles with velocities ~1.2Cs and densities ~1020 m-3 have been achieved. Different distinct regimes of operation with qualitatively different dynamics are identified by fast CCD camera images, with the parameter determining the operation regime. Additionally, a B-dot probe array is employed to measure the spatial toroidal and poloidal magnetic flux evolution to identify detached plasma bubble configurations. Experimental data and analysis will be presented.

  6. Evaporation rates and vapor pressures of individual aerosol species formed in the atmospheric oxidation of alpha- and beta-pinene.

    Science.gov (United States)

    Bilde, M; Pandis, S N

    2001-08-15

    The semivolatile oxidation products (trans-norpinic acid, pinic acid, cis-pinonic acid, etc.) of the biogenic monoterpenes (alpha-pinene, beta-pinene, etc.) contribute to the atmospheric burden of particulate matter. Using the tandem differential mobility analysis (TDMA) technique evaporation rates of glutaric acid, trans-norpinic acid, and pinic acid particles were measured in a laminar flow reactor. The vapor pressure of glutaric acid was found to be log(p0 glutaric/Pa) = - 3,510 K/T + 8.647 over the temperature range 290-300 K in good agreement with the values previously reported by Tao and McMurry (1989). The measured vapor pressure of trans-norpinic acid over the temperature range 290-312 K is log(p0 norpinic/Pa) = - 2,196.9 K/T + 3.522, and the vapor pressure of pinic acid is log(p0 pinic/ Pa) = - 5,691.7 K/T + 14.73 over the temperature range 290-323 K. The uncertainty on the reported vapor pressures is estimated to be approximately +/- 50%. The vapor pressure of cis-pinonic acid is estimated to be of the order of 7 x 10(-5) Pa at 296 K.

  7. Thin film fabrication of PMMA/MEH-PPV immiscible blends by corona discharge coating and its application to polymer light emitting diodes.

    Science.gov (United States)

    Jung, Hee Joon; Park, Youn Jung; Choi, Sang Hun; Hong, Jae-Min; Huh, June; Cho, Jun Han; Kim, Jung Hyun; Park, Cheolmin

    2007-02-13

    We introduce a new and facile process, corona discharge coating (CDC), to fabricate thin polymer films of the immiscible poly[2-methoxy-5-(2'-ethylhexyloxy)-p-phenylenevinylene] (MEH-PPV) and poly(methyl methacrylate) (PMMA) blends. The method is based on utilizing directional electric flow, known as electric wind, of the charged unipolar particles generated by corona discharge between a metallic needle and a bottom plate under high electric field (5-10 kV/cm). The electric flow rapidly spreads out the polymer solution on the bottom plate and subsequently forms a smooth and flat thin film over a large area within a few seconds. The method is found to be effective for fabricating uniform thin polymer films with areas larger than approximately 30 mm2. The thin films obtained by CDC exhibit unique microstructures where well-defined spherical and cylindrical domains of approximately 50 nm in diameter coexist. These nanosized domains are found to be much smaller than those in films made by conventional spin coating, which suggests that CDC is beneficial for fabricating phase-separated thin film structures with significantly increased interfacial areas. The effects of the applied voltage, tip-to-plate distance, and substrates on the film formation as well as the resulting microstructure are investigated. Furthermore, the light emitting performance of a device prepared by CDC is compared with one made by spin coating. PMID:17279712

  8. After-pulse from helium-filled proportional counter at low temperatures near 4.2 K

    International Nuclear Information System (INIS)

    After-pulses, which appear in output signals from the helium-filled proportional counter (HFPC) cooled at low temperature (5-10 K), have been analyzed with a technique of non-linear least-squares fit; the drift time Ti of positive helium ions from anode to cathode, the spread in the drift time ΔTi and the second Townsend ionization coefficient Γi of the positive ions have been determined. It is known that the carrier of positive charge in pure helium gas is the dimer ion He+2 at room temperature. We have found that Ti and ΔTi are larger than the values estimated with the mobility of He+2 and Γi is much smaller than the value for He+2. These results indicate that the carrier at low temperatures near 4.2 K is not He+2, but heavier molecular ions He+n; the size n is more than 10 in the present HFPC. It has been concluded that the cluster ion of large molecular helium plays an essential role in the proportional operation of HFPC, especially to suppress the continuous electric discharge. This self-suppression of discharge by the formation of cluster ions is discussed with some data of atomic and molecular heliums. The same quenching mechanism by cluster ions in other rare gases is also suggested. ((orig.))

  9. Vibration-induced electrical noise in a cryogen-free dilution refrigerator: Characterization, mitigation, and impact on qubit coherence

    Science.gov (United States)

    Kalra, Rachpon; Laucht, Arne; Dehollain, Juan Pablo; Bar, Daniel; Freer, Solomon; Simmons, Stephanie; Muhonen, Juha T.; Morello, Andrea

    2016-07-01

    Cryogen-free low-temperature setups are becoming more prominent in experimental science due to their convenience and reliability, and concern about the increasing scarcity of helium as a natural resource. Despite not having any moving parts at the cold end, pulse tube cryocoolers introduce vibrations that can be detrimental to the experiments. We characterize the coupling of these vibrations to the electrical signal observed on cables installed in a cryogen-free dilution refrigerator. The dominant electrical noise is in the 5-10 kHz range and its magnitude is found to be strongly temperature dependent. We test the performance of different cables designed to diagnose and tackle the noise, and find triboelectrics to be the dominant mechanism coupling the vibrations to the electrical signal. Flattening a semi-rigid cable or jacketing a flexible cable in order to restrict movement within the cable, successfully reduces the noise level by over an order of magnitude. Furthermore, we characterize the effect of the pulse tube vibrations on an electron spin qubit device in this setup. Coherence measurements are used to map out the spectrum of the noise experienced by the qubit, revealing spectral components matching the spectral signature of the pulse tube.

  10. Impact of Organic and Inorganic Fertilizers Application on the Phytochemical and Antioxidant Activity of Kacip Fatimah (Labisia pumila Benth

    Directory of Open Access Journals (Sweden)

    Ehsan Karimi

    2013-09-01

    Full Text Available A study was conducted to compare secondary metabolites and antioxidant activity of Labisia pumila Benth (Kacip Fatimah in response to two sources of fertilizer [i.e., organic (chicken dung; 10% N:10% P2O5:10% K2O and inorganic fertilizer (NPK green; 15% N, 15% P2O5, 15% K2O] under different N rates of 0, 90, 180 and 270 kg N/ha. The experiment was arranged in a randomized complete block design replicated three times. At the end of 15 weeks, it was observed that the application of organic fertilizer enhanced the production of total phenolics, flavonoids, ascorbic acid, saponin and gluthathione content in L. pumila, compared to the use of inorganic fertilizer. The nitrate content was also reduced under organic fertilization. The application of nitrogen at 90 kg N/ha improved the production of secondary metabolites in Labisia pumila. Higher rates in excess of 90 kg N/ha reduced the level of secondary metabolites and antioxidant activity of this herb. The DPPH and FRAP activity was also highest at 90 kg N/ha. The results indicated that the use of chicken dung can enhance the production of secondary metabolites and improve antioxidant activity of this herb.

  11. Modelling the stability of maltodextrin-encapsulated grape skin phenolics used as a new ingredient in apple puree.

    Science.gov (United States)

    Lavelli, V; Sri Harsha, P S C; Spigno, G

    2016-10-15

    Highly soluble maltodextrin-encapsulated grape skin phenolics comprising anthocyanins and less hydrophilic flavonoids were added as an ingredient to apple puree. Upon formulation, heat treatments were applied to achieve 3-14 decimal reductions (D) of the target microorganism (Alicyclobacillus acidoterrestris). A storage study was performed at 15-35°C for 1month. Monomeric anthocyanins were retained at 100% after the 3 D treatment, while anthocyanin retention decreased to 72% with increasing heating intensity until 14 D. During storage, the concentration of monomeric anthocyanins decreased following first-order kinetics (k25°C=34.4d(-1), activation energy=51.0kJ/mol). The flavanols were more stable than the monomeric anthocyanins. The hydroxycinnamic acid, dihydrochalcone and flavonol contents did not change. The fortified puree had a two-fold higher reducing capacity with respect to apple puree. Overall, this ingredient could meet the industrial demand for sustainable colouring agents and health promoting compounds. PMID:27173570

  12. An experiment study of homogeneous charge compression ignition combustion and emission in a gasoline engine

    Directory of Open Access Journals (Sweden)

    Zhang Jianyong

    2014-01-01

    Full Text Available Homogenous charge compression ignition (HCCI technology has exhibited high potential to reduce fuel consumption and NOx emissions over normal spark ignition engines significantly. Optimized kinetic process (OKP technology is implemented to realize HCCI combustion in a port fuel injection gasoline engine. The combustion and emission characteristics are investigated with variation of intake air temperature, exhaust gas recirculation (EGR rate and intake air pressure. The results show that intake air temperature has great influence on HCCI combustion characteristic. Increased intake air temperature results in advance combustion phase, shorten combustion duration, and lower indicated mean effective pressure (IMEP. Increased EGR rate retards combustion start phase and prolongs combustion duration, while maximum pressure rising rate and NOx emission are reduced with increase of EGR rate. In the condition with constant fuel flow quantity, increased air pressure leads to retarded combustion phase and lower pressure rising rate, which will reduce the engine knocking tendency. In the condition with constant air fuel ratio condition, fuel injection quantity increases as intake air pressure increases, which lead to high heat release rate and high emission level. The optimal intake air temperature varies in different operating area, which can be tuned from ambient temperature to 220℃ by heat management system. The combination of EGR and air boost technology could expand operating area of HCCI engine, which improve indicated mean effective pressure from maximum 510kPa to 720kPa.

  13. Influence of various forms of dialyzable leukocyte extracts on rat adjuvant arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Stancikova, Maria; Rovensky, Jozef; Blazickova, Stanislava [Research Institute of Rheumatic Diseases, Piestany (Slovakia); Pekarek, J.; Cech, Karel [Institute of Sera and Vaccines, Prague (Czech Republic)

    1994-12-31

    Adjuvant-induced arthritis in rats is a chronic inflammatory disease, widely as an animal model for rheumatoid arthritis. In our study the effect of various fractions of dialyzable leukocyte extract (DLE): DLE I-molecular weight below 10 kDa (commercial preparation), DLE II-molecular weight below 5 kDa (suppressor fraction), DLE III-molecular weight 5-10 kDa on rat adjuvant-induced arthritis was studied. The adjuvant arthritic (AA) rats were treated with DLE fractions i.p. in solutions containing an active substance isolated from 12.5 x 10{sup 6} and 6.25 x 10{sup 6} leukocytes from day 1 (adjuvant injected) through day 18, every second day (total 9 times). Various markers in inflammation, immune function and joint destruction were evaluated: hind paw volume, serum hyaluronic acid, serum albumin and biopterin in urine. All these markers showed a significant improvement after using fraction DLE II in comparison with AA controls. Fractions DLE I and DLE III influenced only some markers of inflammation and immune function. Our results demonstrated a therapeutical effect of fraction DLE II on rat adjuvant-induced arthritis. (author). 22 refs, 2 figs, 2 tabs.

  14. Liver Full Reference Set Application: Hiro Yamada - Wako (2011) — EDRN Public Portal

    Science.gov (United States)

    Wako has received new 510(k) clearance for Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3) and Des-gamma-carboxy prothrombin (DCP) tests on an innovative μTASWako i30 analyzer from FDA. The AFP-L3 and DCP assayed on an older platform LiBASys have been cleared with indication of use for risk assessment of hepatocellular carcinoma (HCC) in patient at risk for the liver malignancy. Wako believes that early detection of HCC is critical for improving HCC patient outcome. Therefore, Wako is currently seeking collaborative opportunities to retrospectively measure clinical samples using the AFP-L3 and DCP for further determining of effectiveness of the HCC biomarkers in early detection which are collected prospectively during HCC surveillance. The Reference Sample Set in the EDRN biorepository are well characterized and studied. Access to these samples would allow Wako to quickly determine the clinical effectiveness of AFP-L3 and DCP in detecting early HCC

  15. Electrical and dielectric spectroscopic characterization of polycrystalline Dy/sub 2/Si/sub 2/O/sub 7/

    International Nuclear Information System (INIS)

    The compound Dy/sub 2/Si/sub 2/O/sub 7/ exists in two polymorphs, the low temperature triclinic phase (type B) and a high temperature orthorhombic phase (type E). The dc and ac electrical conductivities of E-Dy/sub 2/Si/sub 2/O/sub 7/ are measured in the temperature range 290-510 K and frequency range 1 kHz to 1 MHz. The dc electrical transport data are analyzed according to Mott's variable-range hopping model. The disorder parameter (T/sub o/) and density of states at fermi level are obtained. The ac conductivity sigma/sub ac/ (omega) is obtained through the dielectric parameters. The ac conductivity can be expressed as sigma/sub ac/ (omega) = B sigma/sup s/ , where s is slope and it decreases with increase in temperature. The conduction mechanism in the compound is discussed in low and high temperature regions in the light of theoretical models. (author)

  16. Scientific Opinion on the essential composition of total diet replacements for weight control

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA

    2015-01-01

    Full Text Available Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA was asked to deliver a scientific opinion on the essential composition of total diet replacements for weight control. Total diet replacements for weight control are intended to induce a substantial energy deficit in overweight or obese adults who wish to lose weight and replace the whole diet in the context of energy-restricted diets for weight reduction. In this opinion, the Panel proposed a minimum protein content based on a Population Reference Intake for protein adjusted for the overweight or obese (75 g/day, a minimum carbohydrate content based on the obligatory glucose demands of the brain (30 g/day and minimum contents of linoleic acid (11 g/day, α-linolenic acid (1.4 g/day and micronutrients based on reference values established either by the Panel or by other scientific or authoritative bodies. Derived from the minimum content of macronutrients, the Panel proposed a minimum energy content of total diet replacements for weight control of 2 510 kJ/day (600 kcal/day. The Panel also advised on potential conditions and restrictions of use for these products.

  17. Are mussels able to distinguish underwater sounds? Assessment of the reactions of Mytilus galloprovincialis after exposure to lab-generated acoustic signals.

    Science.gov (United States)

    Vazzana, Mirella; Celi, Monica; Maricchiolo, Giulia; Genovese, Lucrezia; Corrias, Valentina; Quinci, Enza Maria; de Vincenzi, Giovanni; Maccarrone, Vincenzo; Cammilleri, Gaetano; Mazzola, Salvatore; Buscaino, Giuseppa; Filiciotto, Francesco

    2016-11-01

    This study examined the effects of lab-generated acoustic signals on the behaviour and biochemistry of Mediterranean mussels (Mytilus galloprovincialis). The experiment was carried out in a tank equipped with a video-recording system using six groups of five mussels exposed to five acoustic treatments (each treatment was replicated three times) for 30min. The acoustic signals, with a maximum sound pressure level of 150dB rms re 1μPa, differed in frequency range as follows: low (0.1-5kHz), mid-low (5-10kHz), mid (10-20kHz), mid-high (20-40kHz) and high (40-60kHz). The exposure to sweeps did not produce any significant changes in the mussels' behaviour. Conversely, the specimens exposed to the low frequency band treatment showed significantly higher values of the following biochemical stress parameters measured in their plasma and tissues: glucose, total proteins, total haemocyte number (THC), heat shock protein 70 (Hsp70) expression, and Acetylcholinesterase (AChE) activity. The responses observed in the mussels exposed to low frequency sweeps enable us to suppose a biological and ecological role for this sound, which contains the main frequencies produced by both shipping traffic and the acoustic emissions of fish.

  18. Adsorption, desorption, and film formation of quinacridone and its thermal cracking product indigo on clean and carbon-covered silicon dioxide surfaces

    Science.gov (United States)

    Scherwitzl, Boris; Lassnig, Roman; Truger, Magdalena; Resel, Roland; Leising, Günther; Winkler, Adolf

    2016-09-01

    The evaporation of quinacridone from a stainless steel Knudsen cell leads to the partial decomposition of this molecule in the cell, due to its comparably high sublimation temperature. At least one additional type of molecules, namely indigo, could be detected in the effusion flux. Thermal desorption spectroscopy and atomic force microscopy have been used to study the co-deposition of these molecules on sputter-cleaned and carbon-covered silicon dioxide surfaces. Desorption of indigo appears at temperatures of about 400 K, while quinacridone desorbs at around 510 K. For quinacridone, a desorption energy of 2.1 eV and a frequency factor for desorption of 1 × 1019 s-1 were calculated, which in this magnitude is typical for large organic molecules. A fraction of the adsorbed quinacridone molecules (˜5%) decomposes during heating, nearly independent of the adsorbed amount, resulting in a surface composed of small carbon islands. The sticking coefficients of indigo and quinacridone were found to be close to unity on a carbon covered SiO2 surface but significantly smaller on a sputter-cleaned substrate. The reason for the latter can be attributed to insufficient energy dissipation for unfavorably oriented impinging molecules. However, due to adsorption via a hot-precursor state, the sticking probability is increased on the surface covered with carbon islands, which act as accommodation centers.

  19. Temperature-Sensing Behavior Based on Upconversion Luminescence at the Rhombohedral-Tetragonal Phase Boundary

    Science.gov (United States)

    Zou, Hua; Hu, Yifeng; Zhu, Xiaoqin; Zhang, Jianhao; Wang, Xusheng; Song, Zhitang

    2016-10-01

    In this work, (1- x)(K0.48Na0.52)(Nb0.95Sb0.05)O3- x - xEr0.5(Na0.82K0.18)0.5ZrO3 ( x = 0-0.05) ceramics were fabricated by solid-state reaction techniques. The rhombohedral-tetragonal (R-T) phase boundary of the ceramics was identified at 0.04 ≤ x, thus providing an opportunity to investigate the upconversion emission derived from the Er3+ ions at the R-T phase boundary. Under 980 nm laser excitation, the R-T phase ceramics exhibited a strong green emission. In addition, the fluorescence intensity ratios of green emissions at 530 nm and 550 nm were investigated in a temperature range of 180-510 K, and maximum sensing sensitivity was found to be 0.0037 K-1. The results indicate that Er3+-doped ceramics with R-T phase boundaries can be applied to new multifunctional electro-optical temperature sensors. Laser excitation heating effects were also observed in detail.

  20. Adsorption, desorption, and film formation of quinacridone and its thermal cracking product indigo on clean and carbon-covered silicon dioxide surfaces.

    Science.gov (United States)

    Scherwitzl, Boris; Lassnig, Roman; Truger, Magdalena; Resel, Roland; Leising, Günther; Winkler, Adolf

    2016-09-01

    The evaporation of quinacridone from a stainless steel Knudsen cell leads to the partial decomposition of this molecule in the cell, due to its comparably high sublimation temperature. At least one additional type of molecules, namely indigo, could be detected in the effusion flux. Thermal desorption spectroscopy and atomic force microscopy have been used to study the co-deposition of these molecules on sputter-cleaned and carbon-covered silicon dioxide surfaces. Desorption of indigo appears at temperatures of about 400 K, while quinacridone desorbs at around 510 K. For quinacridone, a desorption energy of 2.1 eV and a frequency factor for desorption of 1 × 10(19) s(-1) were calculated, which in this magnitude is typical for large organic molecules. A fraction of the adsorbed quinacridone molecules (∼5%) decomposes during heating, nearly independent of the adsorbed amount, resulting in a surface composed of small carbon islands. The sticking coefficients of indigo and quinacridone were found to be close to unity on a carbon covered SiO2 surface but significantly smaller on a sputter-cleaned substrate. The reason for the latter can be attributed to insufficient energy dissipation for unfavorably oriented impinging molecules. However, due to adsorption via a hot-precursor state, the sticking probability is increased on the surface covered with carbon islands, which act as accommodation centers. PMID:27609005

  1. Metabolic engineering of Ralstonia eutropha for the biosynthesis of 2-hydroxyacid-containing polyhydroxyalkanoates.

    Science.gov (United States)

    Park, Si Jae; Jang, Young-Ah; Lee, Hyuk; Park, A-Reum; Yang, Jung Eun; Shin, Jihoon; Oh, Young Hoon; Song, Bong Keun; Jegal, Jonggeon; Lee, Seung Hwan; Lee, Sang Yup

    2013-11-01

    Polyhydroxyalkanoates (PHAs) are bio-based and biodegradable polyesters synthesized by numerous microorganisms. PHAs containing 2-hydroxyacids as monomer units have attracted much attention, but their production has not been efficient. Here, we metabolically engineered Ralstonia eutropha strains for the in vivo synthesis of PHAs containing 2-hydroxyacids as monomers. This was accomplished by replacing the R. eutropha phaC gene in the chromosome with either the R. eutropha phaC S506G A510K gene, which contains two point mutations, or the Pseudomonas sp. MBEL 6-19 phaC1437 gene. In addition, the R. eutropha phaAB genes in the chromosome were replaced with the Clostridium propionicum pct540 gene. All of the engineered R. eutropha strains produced PHAs containing 2-hydroxyacid monomers, including lactate and 2-hydroxybutyrate (2HB), along with 3-hydroxybutyrate (3HB) and/or 3-hydroxyvalerate (3HV), when they were cultured in nitrogen-free medium containing 5 g/L lactate or 4 g/L 2HB and 20 g/L glucose as carbon sources. Expression of the Escherichia coli ldhA gene in engineered R. eutropha strains allowed production of poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)] from glucose as the sole carbon source. This is the first report on the production of 2-hydroxyacid-containing PHAs by metabolically engineered R. eutropha.

  2. Enhancement of localization phenomena driven by covalency in the SrBiMn{sub 1.75}Ti{sub 0.25}O{sub 6} manganite

    Energy Technology Data Exchange (ETDEWEB)

    Asensio de Lucas, E.; Alvarez-Serrano, I. [Depto. Quimica Inorganica I, Facultad Ciencias Quimicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Cuello, G.J. [Institut Laue-Langevin, 6 rue Jules Horowitz, F-38042 Grenoble (France); Garcia-Hernandez, M. [Instituto de Ciencia de Materiales de Madrid, CSIC, E-28049 Cantoblanco, Madrid (Spain); Lopez, M.L., E-mail: marisal@quim.ucm.es [Depto. Quimica Inorganica I, Facultad Ciencias Quimicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Pico, C.; Veiga, M.L. [Depto. Quimica Inorganica I, Facultad Ciencias Quimicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain)

    2012-05-05

    Graphical abstract: Enhancement of localization phenomena driven by covalency in the BiSrMn{sub 1.75}Ti{sub 0.25}O{sub 6} manganite. The CO/OO phenomena and magnetic clusters (Mn{sub 4}) stabilization at temperatures up to 520 K in BiSrMn{sub 1.75}Ti{sub 0.25}O{sub 6} are connected to a structural transition. The observed enhancement of electronic localization is interpreted considering covalent effects of Ti{sup 4+} and Bi{sup 3+} cations as the main driving force. Highlights: Black-Right-Pointing-Pointer The structural, electronic and magnetic behaviour of the new SrBiMn{sub 1.75}Ti{sub 0.25}O{sub 6} manganite is reported. Black-Right-Pointing-Pointer A structural transition above 520 K takes place, coinciding with relevant changes in the transport properties. Black-Right-Pointing-Pointer The electronic behavior is interpreted in terms of a remarkably high orbital and charge ordering temperature and cluster models. Black-Right-Pointing-Pointer The observed features are explained considering a scenario in which bonds covalence is enhanced by the Bi{sup 3+} and Ti{sup 4+} cations. - Abstract: Manganites are materials that show remarkable phenomena related to charge orbital ordering (CO/OO) and it is extremely important to understand the fundamental nature of this behaviour. This paper reports on the structural, electronic and magnetic behaviour of the new SrBiMn{sub 1.75}Ti{sub 0.25}O{sub 6} manganite and the dependence of these properties with temperature. A detailed structural analysis has been carried out by electron, X-ray, neutron diffraction between 4 and 700 K. The electron diffraction patterns obtained at room temperature (RT) evidence that the average structure (a{approx}b{approx}{radical}(2)a{sub p} and c {approx} 2a{sub p}) presents a modulation that doubles the a and c lattice parameters. A very high charge ordering (CO) transition temperature of 510 K, similar to that found for the non-doped material, SrBiMn{sub 2}O{sub 6}, is observed. Above this

  3. 含氮化合物碱性强弱的量子力学研究%Quantum mechanical studies on basieity of nitrogen-containing compounds

    Institute of Scientific and Technical Information of China (English)

    王丽新; 沈喜洲; 周涵; 代振宇

    2009-01-01

    利用密度泛函理论的量子力学从头算法,计算原油及石油产品中不同含氮化合物与H+的结合能,并采用COSMO(conductor-like screen model)模型模拟溶剂的介质环境.结果表明,在水溶剂中,含氮化合物与H+结合的强弱与碱性强弱具有密切关系;与H+结合得越强,其碱性就越强;反之,则越弱.因此,可以算出它们在水溶剂中与H+结合能的高低,判断其碱件的强弱.脂肪胺、非芳香杂环氮化物与H+质子的结合能约在-660~-640 kJ/mol之间,吡啶、芳香胺和吡咯类氮化物分别约为-620、-600、-510 kJ/mol,它们的碱性依次减弱.随着N-烷基苯胺烷基链中碳原子数从0增长到6,与H+结合能从-595 kJ/mol降低到-610 kJ/mol,碱性不断增强;烷基链继续增长,结合能变化很小,对碱性影响不大.芳香环的并入以及芳香环的连接方式,对五员和六员杂环氮化物碱性的影响有所不同.不同氮化物碱性的强弱和其结构有关,尤其电子密度的分布状态,其中电子共轭结构对碱性有很大的影响.%DFT-hased (density functional theory) ab initio quantum mechanical methods have been applied to calculate the pmtonation energies of various nitrogen-containing compounds in petroleum and its products. COSMO (conductor-like screen model) is selected to simulate aqueous solution in the quantum mechanical calculation. The results show that there is a distinct relationship between the pro-tonation energies of nitrogen-containing compounds in aqueous solution and their basicities. The stronger the combination of nitrogen-containing compounds with H + , the higher their basicities. Therefore, the relative basicities of these compounds can be effectively characterized by their protonation energies. The protonation energies of aliphatic amines and nonaromatic heterocycles are about -660 - -640 kJ/mol. Those of pyridines, aromatic amines and pyrroles are about -620 kJ/mol, -600 kJ/mol, and -510 kJ/mol, re

  4. The Level 2 research product algorithms for the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES)

    Science.gov (United States)

    Baron, P.; Urban, J.; Sagawa, H.; Möller, J.; Murtagh, D. P.; Mendrok, J.; Dupuy, E.; Sato, T. O.; Ochiai, S.; Suzuki, K.; Manabe, T.; Nishibori, T.; Kikuchi, K.; Sato, R.; Takayanagi, M.; Murayama, Y.; Shiotani, M.; Kasai, Y.

    2011-10-01

    This paper describes the algorithms of the level-2 research (L2r) processing chain developed for the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES). The chain has been developed in parallel to the operational chain for conducting researches on calibration and retrieval algorithms. L2r chain products are available to the scientific community. The objective of version 2 is the retrieval of the vertical distribution of trace gases in the altitude range of 18-90 km. A theoretical error analysis is conducted to estimate the retrieval feasibility of key parameters of the processing: line-of-sight elevation tangent altitudes (or angles), temperature and ozone profiles. While pointing information is often retrieved from molecular oxygen lines, there is no oxygen line in the SMILES spectra, so the strong ozone line at 625.371 GHz has been chosen. The pointing parameters and the ozone profiles are retrieved from the line wings which are measured with high signal to noise ratio, whereas the temperature profile is retrieved from the optically thick line center. The main systematic component of the retrieval error was found to be the neglect of the non-linearity of the radiometric gain in the calibration procedure. This causes a temperature retrieval error of 5-10 K. Because of these large temperature errors, it is not possible to construct a reliable hydrostatic pressure profile. However, as a consequence of the retrieval of pointing parameters, pressure induced errors are significantly reduced if the retrieved trace gas profiles are represented on pressure levels instead of geometric altitude levels. Further, various setups of trace gas retrievals have been tested. The error analysis for the retrieved HOCl profile demonstrates that best results for inverting weak lines can be obtained by using narrow spectral windows.

  5. 关于骨科脊柱产品申报美国上市前通告和国内注册申报资料的要求对比研究%A Comparative Study on the Premarket Notiifcation in the United States and the Requirements for Domestic Registration for Orthopedic Spinal Products

    Institute of Scientific and Technical Information of China (English)

    孔玮娜; 程云章

    2016-01-01

    The newly revised Provisions forMedical Device Registration (CFDA No.4) andRequirements and Instructions for Medical Device Registration Application (CFDA No.43) introduced the idea of premarket notiifcation 510k of US Food and Drug Administration (FDA). This study made a comparison between the Requirements and Instructions for Medical Device Registration Application and theGuidance for Industry with the Guidance for Industry and FDA Staff Format for Traditional and Abbreviated 510ks. By using the orthopedic spinal products as examples, this paper analyzes the similarities and differences between the two documents, in order to provide guidance and assistance for the medical device registration dossiers preparation.%新修订的《医疗器械注册管理办法》(食品药品监督管理总局令第4号)及配套的《关于公布医疗器械注册申报资料要求和批准证明文件格式的公告》(食品药品监督管理总局令第43号)引入了美国FDA申报510k的思路,本文通过将《医疗器械注册申报资料要求及说明》和美国FDA《传统和简化510k的格式指导原则》(Guidance for Industry and FDA Staff Format for Traditional and Abbreviated 510ks)做对比,以骨科脊柱产品为例,浅析二者之间的异同点,以期对医疗器械注册申报资料的准备工作提供指导和帮助。

  6. High average power CO II laser MOPA system for Tin target LPP EUV light source

    Science.gov (United States)

    Ariga, Tatsuya; Hoshino, Hideo; Endo, Akira

    2007-02-01

    Extreme ultraviolet lithography (EUVL) is the candidate for next generation lithography to be introduced by the semiconductor industry to HVM (high volume manufacturing) in 2013. The power of the EUVL light source has to be at least 115W at a wavelength of 13.5nm. A laser produced plasma (LPP) is the main candidate for this light source but a cost effective laser driver is the key requirement for the realization of this concept. We are currently developing a high power and high repetition rate CO II laser system to achieve 50 W intermediate focus EUV power with a Tin droplet target. We have achieved CE of 2.8% with solid Tin wire target by a transversely excited atmospheric (TEA) CO II laser MOPA system with pulse width, pulse energy and pulse repetition rate as 10~15 ns, 30 mJ and 10 Hz, respectively. A CO II laser system with a short pulse length less than 15 ns, a nominal average power of a few kW, and a repetition rate of 100 kHz, based on RF-excited, fast axial flow CO II laser amplifiers is under development. Output power of about 3 kW has been achieved with a pulse length of 15 ns at 130 kHz repletion rate in a small signal amplification condition with P(20) single line. The phase distortion of the laser beam after amplification is negligible and the beam can be focused to about 150μm diameter in 1/e2. The CO II laser system is reported on short pulse amplification performance using RF-excited fast axial flow lasers as amplifiers. And the CO II laser average output power scaling is shown towards 5~10 kW with pulse width of 15 ns from a MOPA system.

  7. Effects of direct current on the wetting behavior and interfacial morphology between molten Sn and Cu substrate

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Yan; Shen, Ping, E-mail: shenping@jlu.edu.cn; Yang, Nan-Nan; Cao, Kang-Zhan

    2014-02-15

    Highlights: • Applying DC has a noticeable effect on the wetting of oxidized Cu by molten Sn. • Current polarity does not have a strong effect on wettability but on microstructure. • The IMC layer greatly thickens with increasing current intensity. • An unusual morphology was formed at the interface under a larger current intensity. -- Abstract: The effect of applying a direct electric current on the wetting behavior of molten Sn on Cu substrates at a nominal temperature of 510 K was investigated using a sessile drop method. The final stable contact angles were 37 ± 5° without employing a direct current (DC) while they decreased from 29 ± 3° to 16 ± 2° when the current increased from 2.5 A to 7.5 A. The current polarity does not have a noticeable effect on the wetting behavior but on interfacial morphology. Cross-sectional microstructure observations revealed that applying a current promoted the dissolution of the Cu substrate in molten Sn and the effect was enhanced with increasing current intensity. An unusual morphology with Cu{sub 3}Sn being the principal phase and Cu{sub 6}Sn{sub 5} being the secondary phase was observed under a relatively large current intensity, particularly for the case of electrons flowing from the Cu substrate to the molten Sn side. Joule heat-induced Marangoni convection in the liquid droplet and electromigration are likely to play significant roles in determining the wettability and interfacial microstructure under the application of a direct electric current.

  8. Multi-modal vibration based MEMS energy harvesters for ultra-low power wireless functional nodes

    Science.gov (United States)

    Iannacci, J.; Gottardi, M.; Serra, E.; Di Criscienzo, R.; Borrielli, A.; Bonaldi, M.

    2013-05-01

    The aim of this contribution is to report and discuss a preliminary study and rough optimization of a novel concept of MEMS device for vibration energy harvesting, based on a multi-modal dynamic behavior. The circular-shaped device features Four-Leaf Clover-like (FLC) double spring-mass cascaded systems, kept constrained to the surrounding frame by means of four straight beams. The combination of flexural bending behavior of the slender beams plus deformable parts of the petals enable to populate the desired vibration frequency range with a number of resonant modes, and improve the energy conversion capability of the micro-transducer. The harvester device, conceived for piezoelectric mechanical into electric energy conversion, is intended to sense environmental vibrations and, thereby, its geometry is optimized to have a large concentration of resonant modes in a frequency range below 5-10 kHz. The results of FEM (Finite Element Method) based analysis performed in ANSYSTM Workbench are reported, both concerning modal and harmonic response, providing important indications related to the device geometry optimization. The analysis reported in this work is limited to the sole mechanical modeling of the proposed MEMS harvester device concept. Future developments of the study will encompass the inclusion of piezoelectric conversion in the FEM simulations, in order to have indications of the actual power levels achievable with the proposed harvester concept. Furthermore, the results of the FEM studies here discussed, will be validated against experimental data, as soon as the MEMS resonator specimens, currently under fabrication, are ready for testing.

  9. Increased epidermal laser fluence through simultaneous ultrasonic microporation

    Science.gov (United States)

    Whiteside, Paul J. D.; Chininis, Jeff A.; Schellenberg, Mason W.; Qian, Chenxi; Hunt, Heather K.

    2016-03-01

    Lasers have demonstrated widespread applicability in clinical dermatology as minimally invasive instruments that achieve photogenerated responses within tissue. However, before reaching its target, the incident light must first transmit through the surface layer of tissue, which is interspersed with chromophores (e.g. melanin) that preferentially absorb the light and may also generate negative tissue responses. These optical absorbers decrease the efficacy of the procedures. In order to ensure that the target receives a clinically relevant dose, most procedures simply increase the incident energy; however, this tends to exacerbate the negative complications of melanin absorption. Here, we present an alternative solution aimed at increasing epidermal energy uence while mitigating excess absorption by unintended targets. Our technique involves the combination of a waveguide-based contact transmission modality with simultaneous high-frequency ultrasonic pulsation, which alters the optical properties of the tissue through the agglomeration of dissolved gasses into micro-bubbles within the tissue. Doing so effectively creates optically transparent pathways for the light to transmit unobstructed through the tissue, resulting in an increase in forward scattering and a decrease in absorption. To demonstrate this, Q-switched nanosecond-pulsed laser light at 532nm was delivered into pig skin samples using custom glass waveguides clad in titanium and silver. Light transmission through the tissue was measured with a photodiode and integrating sphere for tissue with and without continuous ultrasonic pulsation at 510 kHz. The combination of these techniques has the potential to improve the efficiency of laser procedures while mitigating negative tissue effects caused by undesirable absorption.

  10. Kinetically driven self-assembly of a binary solute mixture with controlled phase separation via electro-hydrodynamic flow of corona discharge.

    Science.gov (United States)

    Jung, Hee Joon; Huh, June; Park, Cheolmin

    2012-10-21

    This feature article describes a new and facile process to fabricate a variety of thin films of non-volatile binary solute mixtures suitable for high performance organic electronic devices via electro-hydrodynamic flow of conventional corona discharge. Both Corona Discharge Coating (CDC) and a modified version of CDC, Scanning Corona Discharge Coating (SCDC), are based on utilizing directional electric flow, known as corona wind, of the charged uni-polar particles generated by corona discharge between a metallic needle and a bottom plate under a high electric field (5-10 kV cm(-1)). The electric flow rapidly spreads out the binary mixture solution on the bottom plate and subsequently forms a smooth and flat thin film in a large area within a few seconds. In the case of SCDC, the static movement of the bottom electrode on which a binary mixture solution is placed provides further control of thin film formation, giving rise to a film highly uniform over a large area. Interesting phase separation behaviors were observed including nanometer scale phase separation of a polymer-polymer binary mixture and vertical phase separation of a polymer-organic semiconductor mixture. Core-shell type phase separation of either polymer-polymer or polymer-colloidal nanoparticle binary mixtures was also developed with a periodically patterned microstructure when the relative location of the corona wind was controlled to a binary solution droplet on a substrate. We also demonstrate potential applications of thin functional films with controlled microstructures by corona coating to various organic electronic devices such as electroluminescent diodes, field effect transistors and non-volatile polymer memories. PMID:22990240

  11. TiO2 effect on crystallization mechanism and physical properties of nano glass-ceramics of MgO-Al2O3-SiO2 glass system.

    Science.gov (United States)

    Jo, Sinae; Kang, Seunggu

    2013-05-01

    The effect of TiO2 on the degree of crystallization, thermal properties and microstructure for MgO-Al2O3-SiO2 glass-ceramics system containing 0-13 wt% TiO2 and 0-1.5 wt% B2O3 in which the cordierite is the main phase was studied. Using Kissinger and Augis-Bennett equations, the activation energy, 510 kJ/mol and Avrami constant, 1.8 were calculated showing the surface-oriented crystallization would be preferred. The alpha-cordierite phase was generated in the glass-ceramics of containing TiO2 of 0-5.6 wt%. However, for the glass-ceramics of TiO2 content above 7 wt%, an alpha-cordierite disappeared and micro-cordierite phase was formed. The glass-ceramics of no TiO2 added had spherical crystals of few tens nanometer size spread in the matrix. As TiO2 content increased up to 5.6 wt%, a lump of dendrite was formed. In the glass-ceramics containing TiO2 7-13 wt%, in which the main phase is micro-cordierite, the dendrite crystal disappeared and a few hundred nanometer sized crystal particles hold tightly each other were generated. The thermal conductivity of glass-ceramics of both a-cordierite and micro-cordierite base decreased with TiO2 contend added. The thermal conductivity of glass-ceramics of 1.5 wt% TiO2 added was 3.4 W/mK which is 36% higher than that of glass-ceramics of no TiO2 added. The sintering temperature for 1.5 wt% TiO2 glass-ceramics was 965 degrees C which could be concluded as to apply to LTCC process for LED packaging. PMID:23858898

  12. Pulsed microwave discharges in powder mixtures: Status, problems, and prospects

    Science.gov (United States)

    Batanov, G. M.; Kossyi, I. A.

    2015-10-01

    Results of experiments on the excitation of pulsed microwave discharges by gyrotron radiation (λ = 4 mm, P 0 = 100-500 kW, τ = 1-10 ms) in the volumes and on the surfaces of metal-dielectric powder mixtures are presented. It is shown that there are two phases of discharge development: the spark phase, accompanied by a partial evaporation of the powder material, and the phase of a developed discharge, characterized by a plasma density of ˜1017 cm-3, high absorption, and high temperatures (˜5-10 kK) in a thin layer (˜0.1-0.2 mm) of plasma and vapor. It is demonstrated that the conductivity induced in the targets by UV radiation play an important role in the microwave absorption by powder grains. It is found that, in the course of the discharge, a conductive metal mesh forms in the powder volume as a result of metal evaporation. Reactions of high-temperature synthesis were initiated in various powder mixtures (Ti + B, Al + Fe2O3, Mo + B, etc.). It is shown that the reactions of high-temperature synthesis last for up to 0.1 s and are accompanied by the evaporation of powder grains and the formation of an aerosol cloud due to free expansion of reactants from the sample surface. The possibility of experimentally studying the kinetics of reactions of high-temperature synthesis is demonstrated. It is noticed that microwave discharges can be used to initiate plasmachemical reactions on the surfaces of radioparent materials in active gaseous media.

  13. Structure and Anti-influenza A (H1N1) Virus Activity of Three Polysaccharides from Eucheuma denticulatum

    Institute of Scientific and Technical Information of China (English)

    YU Guangli; LI Miaomiao; WANG Wei; LIU Xin; ZHAO Xiaoliang; LV Youjing; LI Guangsheng; JIAO Guangling; ZHAO Xia

    2012-01-01

    Three polysaccharides (EW,EH and EA) were prepared from a red alga Eucheuma denticulatum by sequential extraction with cold water,hot water and sodium hydroxide water solution.Their monosaccharide compositions,relative molecular mass and structural characterization were determined by gas chromatography,high performance liquid chromatography,fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy methods.EW was hybrid ι/κ/v-carrageenan (70ι/17κ/13v-carrabiose),EH was mainly ι-carrageenan,and EA was mainly α-1,4-Glucan (88%) but mixed with small amount of ι-carrageenan (12%).The relative molecular mass of EW,EH and EA was 480,580 and 510kDa,respectively.The anti-influenza A (H1N1) virus activity of these three polysaccharides was evaluated using the Madin-Darby canine kidney cells model.EW showed good anti-H1N1 virus activity,its IC50 was 276.5 μg mL-1,and the inhibition rate to H1N1 virus was 52% when its concentration was 250 μg mL-1.The IC50 of ι-carrageenan EH was 366.4 μgmL-1,whereas EA showed lower anti-H1N1 virus activity (IC50>430 μgmL-1).Available data obtained give positive evidence that the hybrid carrageenan EW from Eucheuma denticulatum can be used as potential anti-H1N1 virus inhibitor in future.

  14. Kinetically driven self-assembly of a binary solute mixture with controlled phase separation via electro-hydrodynamic flow of corona discharge.

    Science.gov (United States)

    Jung, Hee Joon; Huh, June; Park, Cheolmin

    2012-10-21

    This feature article describes a new and facile process to fabricate a variety of thin films of non-volatile binary solute mixtures suitable for high performance organic electronic devices via electro-hydrodynamic flow of conventional corona discharge. Both Corona Discharge Coating (CDC) and a modified version of CDC, Scanning Corona Discharge Coating (SCDC), are based on utilizing directional electric flow, known as corona wind, of the charged uni-polar particles generated by corona discharge between a metallic needle and a bottom plate under a high electric field (5-10 kV cm(-1)). The electric flow rapidly spreads out the binary mixture solution on the bottom plate and subsequently forms a smooth and flat thin film in a large area within a few seconds. In the case of SCDC, the static movement of the bottom electrode on which a binary mixture solution is placed provides further control of thin film formation, giving rise to a film highly uniform over a large area. Interesting phase separation behaviors were observed including nanometer scale phase separation of a polymer-polymer binary mixture and vertical phase separation of a polymer-organic semiconductor mixture. Core-shell type phase separation of either polymer-polymer or polymer-colloidal nanoparticle binary mixtures was also developed with a periodically patterned microstructure when the relative location of the corona wind was controlled to a binary solution droplet on a substrate. We also demonstrate potential applications of thin functional films with controlled microstructures by corona coating to various organic electronic devices such as electroluminescent diodes, field effect transistors and non-volatile polymer memories.

  15. Realization of 50-way RF cavity combiner for planar triode based pulse power source at 325 MHz

    International Nuclear Information System (INIS)

    Using Planar triodes, it is proposed to realize pulse RF power system which is capable of delivering few 100 kW RF power at a design frequency in the frequency range of 300-1500 MHz; realizing its advantage of high degree of amplitude and phase stability, linearity and capability of withstanding high VSWR. Within its power and operating frequency range, Planar triode based system offers advantage over both klystron/lOT as well as solid-state devices based RF power system. Unlike klystron/lOT based, planar triode is operated with comparatively moderate anode voltage- in the range of 5-10 kV-thus avoiding issues related to high voltage operation; and unlike solid state devices, it require much less supply current to handle and simple thermal management system. For that a 50-way cavity combiner was realized at 325 MHz which can combine RF output available from 5 kW planar triode based RF amplifiers to deliver more than 200 kW pulse RF power system at its design frequency. The combining structure is configured in form of a cylindrical cavity which is coupled to planar triode based amplifiers by means of door-knob type coupler positioned around its periphery at a radial distance decided by required value of coupling factor. For combined RF output, E-field coupling is realized in form of a capacitive stub which provide required coupling between E-probe and the cavity. The overall structure is designed and simulated for the required performance in terms of phase and amplitude imbalance caused due to manufacturing tolerances, insertion losses, isolation between combing ports etc. In the paper design of combining structure is discussed and a scheme is presented to realize pulse RF power source which is capable of delivering few 100 kW pulse RF power at 325 MHz. (author)

  16. Irradiation as a possible substitute to chemical fumigation of food

    International Nuclear Information System (INIS)

    Chemical fumigants such as ethylene dibromide, methyl bromide, and ethylene oxide have been used effectively for many years around the world for insect disinfestation of grains, legumes, fruits and vegetables, and for microbial decontamination of spices and other food products. Controversy over the use of these chemicals has arisen in recent years because of: (1) increased awareness of their toxicity to the operators and consumers through the residues on the treated products; (2) documented carcinogenicity, mutagenicity and reproductive disorder in experimental animals; and (3) the potential of environmental pollution. Irradiation, in the form of gamma-radiation or accelerated electron beam, does not present these problems because it is a physical process. More than three decades of worldwide research has shown irradiated food to be safe for human consumption. The irradiation process is technically efficacious, economically feasible and can be safely used for disinfesting and decontaminating a wide variety of food products including mangoes of the seed-weevil. At the disinfestation dose, irradiation causes no phytotoxicity of fresh commodities, delivers a superior product to the consumer and provides the opportunity for production and marketing of new crops. Irradiation is therefore a possible and the most efficacious substitute to chemical fumigation of food. Currently, more than 13 countries have approved unconditional irradiation of cereal grain products (0.45-1.0 kGy), fruits, vegetables and dried foods (up to 1.0 kGy) for insect disinfestation, and of spices (5-10 kGy) for decontamination. More countries are soon expected to adopt similar legislations in the interest of public health, food safety and high quality products. (author). 47 refs, 2 tabs

  17. RX Herculink Elite® renal stent system: a review of its use for the treatment of renal artery stenosis

    Directory of Open Access Journals (Sweden)

    Colyer Jr

    2012-08-01

    Full Text Available William R Colyer JrDivision of Cardiovascular Medicine, University of Toledo Medical Center, Toledo, OH, USAAbstract: The management of renal artery stenosis (RAS remains controversial. While some evidence suggests that treatment with stent placement is beneficial, randomized trials have failed to demonstrate a significant benefit. Ongoing clinical trials should help to better define the role for stenting of RAS while avoiding limitations seen with earlier trials. When it comes to stenting for RAS, several stents have been used; however, many stents which have been used previously and which are still being used are biliary stents that are used “off-label.” These stents have typically come onto the market through the 510(k pathway. To date, a total of five stents have been approved by the United States Food and Drug Administration for use in the renal arteries. Of the five stents that have received approval, the Bridge™ Extra Support (Medtronic CardioVascular, Santa Rosa, CA and the Palmaz® (Cordis Corporation, Bridgewater, NJ stents are no longer available. Currently, the Express® SD (Boston Scientific, Natick, MA, Formula™ (Cook Medical, Bloomington, IN, and Herculink Elite® (Abbott Vascular, Santa Clara, CA stents are Food and Drug Administration approved and available for use. The Herculink Elite is the most recently approved of the renal stents, having received approval in late 2011. The Herculink Elite stent is the only cobalt chromium stent approved for use in the renal arteries. Although trial data are limited and direct comparisons among renal stents is not possible, the Herculink Elite stent has demonstrated good performance. Additionally, the design of the Herculink Elite offers some advantages that may translate into improved outcomes.Keywords: renal artery stenosis, stenting, FDA approval

  18. Waves and horizontal structures in Titan's thermosphere

    Science.gov (United States)

    Müller-Wodarg, I. C. F.; Yelle, R. V.; Borggren, N.; Waite, J. H.

    2006-12-01

    The Ion Neutral Mass Spectrometer (INMS) on board the Cassini spacecraft carried out in situ measurements of neutral gas composition above 1025 km altitude in Titan's atmosphere during its flybys in October 2004 (TA) and April 2005 (T5). Strong perturbations are present in the N2 and CH4 densities which we interpret as vertically propagating waves. Typical vertical wavelengths range from 170 to 360 km with density and pressure amplitudes reaching 4-12% of the background values and temperature amplitudes of 5-10 K. Amplitudes over our sampled height range, 1025 (T5) or 1176 (TA) to 1600 km, remain roughly constant, implying that the exponential increase in wave amplitudes with height due to the decrease of density is offset by damping. This finding allows us to constrain the wave periods to values in the order of hours. Estimates of wave-induced acceleration of the background thermosphere suggest that the waves we observe could deposit considerable momentum in Titan's thermosphere, thereby coupling the dynamics of the upper atmosphere with that of the middle atmosphere. In addition, we infer latitudinal structures in Titan's thermosphere with a factor of 3-4 increase of mass densities from pole to equator in the northern hemisphere. A preliminary evaluation of local time variations suggests densities and thermospheric temperatures to be largest near dusk, contradicting expectations for a thermosphere driven energetically and dynamically primarily by solar EUV. From the latitudinal density gradients we derived zonal wind speeds of around 245 ± 50 ms-1, implying that Titan's thermosphere, like its stratosphere, could be superrotating. Our analyses were based on the TA and TS flybys only, and future Cassini Titan flybys could either support or invalidate our findings.

  19. Structure and anti-influenza A (H1N1) virus activity of three polysaccharides from Eucheuma denticulatum

    Science.gov (United States)

    Yu, Guangli; Li, Miaomiao; Wang, Wei; Liu, Xin; Zhao, Xiaoliang; Lv, Youjing; Li, Guangsheng; Jiao, Guangling; Zhao, Xia

    2012-12-01

    Three polysaccharides (EW, EH and EA) were prepared from a red alga Eucheuma denticulatum by sequential extraction with cold water, hot water and sodium hydroxide water solution. Their monosaccharide compositions, relative molecular mass and structural characterization were determined by gas chromatography, high performance 1iquid chromatography, fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy methods. EW was hybrid ı/κ/ν-carrageenan (70 ı/17κ/13ν-carrabiose), EH was mainly ı-carrageenan, and EA was mainly α-1,4-Glucan (88%) but mixed with small amount of ı-carrageenan (12%). The relative molecular mass of EW, EH and EA was 480, 580 and 510 kDa, respectively. The anti-influenza A (H1N1) virus activity of these three polysaccharides was evaluated using the Madin-Darby canine kidney cells model. EW showed good anti-H1N1 virus activity, its IC50 was 276.5 μg mL-1, and the inhibition rate to H1N1 virus was 52% when its concentration was 250 μg mL-1. The IC50 of ı-carrageenan EH was 366.4 μg mL-1, whereas EA showed lower anti-H1N1 virus activity (IC50>430 μg mL-1). Available data obtained give positive evidence that the hybrid carrageenan EW from Eucheuma denticulatum can be used as potential anti-H1N1 virus inhibitor in future.

  20. High-resolution label-free vascular imaging using a commercial, clinically approved dermatological OCT scanner

    Science.gov (United States)

    Byers, R. A.; Tozer, G.; Brown, N. J.; Matcher, S. J.

    2016-02-01

    Background and Aim: Recently developed decorrelative techniques such as speckle-variance optical coherence tomography (svOCT) have demonstrated non-invasive depth-resolved imaging of the microcirculation in-vivo. However, bulk tissue motion (BTM) originating from the subject's breathing or heartbeat remains problematic at low imaging speeds, often resulting in full frame decorrelation and a loss of vascular contrast. The aim of this study was to build upon existing svOCT techniques through utilisation of a commercially available, probe-based VivoSight OCT system running at 20 kHz Axial-scan rate. Methods and results: Custom four-dimensional scanning strategies were developed and utilised in order to maximise the interframe correlation during image acquisition. Volumes of structural OCT data were collected from various anatomical regions and processed using the aforementioned svOCT algorithm to reveal angiographic information. Following data collection, three dimensional image registration and novel filtering algorithms were applied to each volume in order to ensure that BTM artefacts were sufficiently suppressed. This enabled accurate visualisation of the microcirculation within the papillary dermis, to a depth of approximately 2mm. Applications of this technique, including quantitative capillary loop density measurement and visualisation of wound healing are demonstrated and enhanced through widefield mosaicing of the svOCT data. Conclusions: Non-invasive microcirculation imaging using an FDA 510(k) approved OCT scanner such as the VivoSight allows direct clinical utilisation of these techniques, in particular for the pathological analysis of skin diseases. This research was supported by BBSRC Doctoral Training Grant: BB/F016840/1. The authors also gratefully acknowledge the use of equipment funded by MRC grant: MR/L012669/1.

  1. Point-Counterpoint: The FDA Has a Role in Regulation of Laboratory-Developed Tests.

    Science.gov (United States)

    Caliendo, Angela M; Hanson, Kimberly E

    2016-04-01

    Since the Food and Drug Administration (FDA) released its draft guidance on the regulation of laboratory-developed tests (LDTs) in October 2014, there has been a flurry of responses from commercial and hospital-based laboratory directors, clinicians, professional organizations, and diagnostic companies. The FDA defines an LDT as an "in vitrodiagnostic device that is intended for clinical use and is designed, manufactured, and used within a single laboratory." The draft guidance outlines a risk-based approach, with oversight of high-risk and moderate-risk tests being phased in over 9 years. High-risk tests would be regulated first and require premarket approval. Subsequently, moderate-risk tests would require a 510(k) premarket submission to the FDA and low-risk tests would need only to be registered. Oversight discretion would be exercised for LDTs focused on rare diseases (defined as fewer than 4,000 tests, not cases, per year nationally) and unmet clinical needs (defined as those tests for which there is no alternative FDA-cleared or -approved test). There was an open comment period followed by a public hearing in early January of 2015, and we are currently awaiting the final decision regarding the regulation of LDTs. Given that LDTs have been developed by many laboratories and are essential for the diagnosis and monitoring of an array of infectious diseases, changes in their regulation will have far-reaching implications for clinical microbiology laboratories. In this Point-Counterpoint, Angela Caliendo discusses the potential benefits of the FDA guidance for LDTs whereas Kim Hanson discusses the concerns associated with implementing the guidance and why these regulations may not improve clinical care. PMID:26791369

  2. Field-induced transition of the magnetic ground state from A-type antiferromagnetic to ferromagnetic order in CsCo2Se2

    Science.gov (United States)

    von Rohr, Fabian; Krzton-Maziopa, Anna; Pomjakushin, Vladimir; Grundmann, Henrik; Guguchia, Zurab; Schnick, Wolfgang; Schilling, Andreas

    2016-07-01

    We report on the magnetic properties of CsCo2Se2 with ThCr2Si2 structure, which we have characterized through a series of magnetization and neutron diffraction measurements. We find that CsCo2Se2 undergoes a phase transition to an antiferromagnetically ordered state with a Néel temperature of {{T}\\text{N}}≈ 66 K. The nearest neighbour interactions are ferromagnetic as observed by the positive Curie-Weiss temperature of \\Theta≈ 51.0 K. We find that the magnetic structure of CsCo2Se2 consists of ferromagnetic sheets, which are stacked antiferromagnetically along the tetragonal c-axis, generally referred to as A-type antiferromagnetic order. The observed magnitude of the ordered magnetic moment at T  =  1.5 K is found to be only 0.20(1){μ\\text{Bohr}}  / Co. Already in comparably small magnetic fields of {μ0}H{{}\\text{MM}}(5~K)≈ 0.3 T, we observe a metamagnetic transition that can be attributed to spin-rearrangements of CsCo2Se2, with the moments fully ferromagnetically saturated in a magnetic field of {μ0}{{H}\\text{FM}}(5~K)≈ 6.4 T. We discuss the entire experimentally deduced magnetic phase diagram for CsCo2Se2 with respect to its unconventionally weak magnetic coupling. Our study characterizes CsCo2Se2, which is chemically and electronically posed closely to the A x Fe2-y Se2 superconductors, as a host of versatile magnetic interactions.

  3. Numerical simulations of the subsurface structure of sunspots

    Science.gov (United States)

    Rempel, M.; Cheung, M.; Birch, A. C.; Braun, D. C.

    2011-12-01

    Knowledge of the subsurface magnetic field and flow structure of sunspots is essential for understanding the processes involved in their formation, dynamic evolution and decay. Information on the subsurface structure can be obtained by either direct numerical modeling or helioseismic inversions. Numerical simulations have reached only in recent years the point at which entire sunspots or even active regions can be modeled including all relevant physical processes such as 3D radiative transfer and a realistic equation of state. We present in this talk results from a series of different models: from simulations of individual sunspots (with and without penumbrae) in differently sized computational domains to simulations of the active region formation process (flux emergence). It is found in all models that the subsurface magnetic field fragments on an intermediate scale (larger than the scale of sunspot fine structure such as umbral dots); most of these fragmentations become visible as light bridges or flux separation events in the photosphere. The subsurface field strength is found to be in the 5-10 kG range. The simulated sunspots are surrounded by large scale flows, the most dominant and robust flow component is a deep reaching outflow with an amplitude reaching about 50% of the convective RMS velocity at the respective depth. The simulated sunspots show helioseismic signatures (frequency dependent travel time shifts) similar to those in observed sunspots. On the other hand it is clear from the simulations that these signatures originate in the upper most 2-3 Mm of the convection zone, since only there substantial perturbations of the wave speed are present. The contributions from deeper layers are insignificant, in particular a direct comparison between an 8 Mm and 16 Mm deep simulation leads to indiscernible helioseismic differences. The National Center for Atmospheric Research is sponsored by the National Science Foundation. This work is in part supported through the NASA SDO Science Center.

  4. Clinical Application of a Silk Fibroin Protein Biologic Scaffold for Abdominal Wall Fascial Reinforcement

    Science.gov (United States)

    Downey, Susan; Agullo, Frank; Lehfeldt, Max R.; Kind, Gabriel M.; Palladino, Humberto; Marshall, Deirdre; Jewell, Mark L.; Mathur, Anshu B.; Bengtson, Bradley P.

    2014-01-01

    Background: Preclinical studies have demonstrated that macroporous silk fibroin protein scaffolds are capable of promoting physiologically durable supportive tissue, which favors application of these engineered tissues for clinical implantation. The safety and effectiveness of a long-lasting, transitory, 510(k)-cleared purified silk fibroin biologic scaffold (SBS) are investigated for soft-tissue support and repair of the abdominal wall. Methods: We conducted a multicenter retrospective review of all consecutive patients who underwent abdominal wall soft-tissue reinforcement with an SBS device between 2011 and 2013. Indications, comorbid conditions, surgical technique, complications, and outcomes were evaluated. Results: We reviewed the records of 172 consecutive patients who received an SBS for soft-tissue support. Of those, 77 patients underwent abdominal wall fascial repair, with a mean follow-up of 18.4 ± 7.5 months. Procedures using an SBS included reinforcement of an abdominal-based flap donor site (31.2%), ventral hernia repair (53.2%), and abdominoplasty (15.6%). The overall complication rate was 6.5%, consisting of 2 wound dehiscences, 1 with device exposure, 1 seroma, 1 infection with explantation, and a perioperative bulge requiring reoperation. There were no reports of hernia. Conclusions: Postoperative complication rates after 18 months were low, and most surgical complications were managed nonoperatively on an outpatient basis without mesh removal. To our knowledge, this is the only series to report on a long-lasting, transitory SBS for abdominal wall repair and reinforcement. Procedure-specific outcome studies are warranted to delineate optimal patient selection and define potential device characteristic advantages. PMID:25506529

  5. Development of a Conceptual Process for Selective CO 2 Capture from Fuel Gas Streams Using [hmim][Tf 2 N] Ionic Liquid as a Physical Solvent

    Energy Technology Data Exchange (ETDEWEB)

    Basha, Omar M.; Keller, Murphy J.; Luebke, David R.; Resnik, Kevin P.; Morsi, Badie I.

    2013-06-04

    The Ionic Liquid (IL) [hmim][Tf2N] was used as a physical solvent in an Aspen Plus simulation, employing the Peng-Robinson Equation of State (P-R EOS) with Boston-Mathias (BM) alpha function and standard mixing rules, to develop a conceptual process for CO2 capture from a shifted warm fuel gas stream produced from Pittsburgh # 8 coal for a 400 MWe power plant. The physical properties of the IL, including density, viscosity, surface tension, vapor pressure and heat capacity were obtained from literature and modeled as a function of temperature. Also, available experimental solubility values for CO2, H2, H2S, CO, and CH4 in this IL were compiled and their binary interaction parameters (Δij and lij) were optimized and correlated as functions of temperature. The Span-Wager Equation-of-State EOS was also employed to generate CO2 solubilities in [hmim][Tf2N] at high pressures (up to 10 MPa) and temperatures (up to 510 K). The conceptual process developed consisted of 4 adiabatic absorbers (2.4 m ID, 30 m high) arranged in parallel and packed with Plastic Pall Rings of 0.025 m for CO2 capture; 3 flash drums arranged in series for solvent (IL) regeneration with the pressure-swing option; and a pressure-intercooling system for separating and pumping CO2 up to 153 bar to the sequestration sites. The compositions of all process streams, CO2 capture efficiency, and net power were calculated using Aspen Plus simulator. The results showed that, based on the composition of the inlet gas stream to the absorbers, 95.67 mol% of CO2 was captured and sent to sequestration sites; 99.5 mol% of H2 was separated and sent to turbines; the solvent exhibited a minimum loss of 0.31 mol%; and the net power balance of the entire system was 30.81 MW. These results indicated that [hmim][Tf2N] IL could be used as a physical

  6. Study of the degradation process of polyimide induced by high energetic ion irradiation

    International Nuclear Information System (INIS)

    The dissertation focuses on the radiation hardness of Kapton under extreme radiation environment conditions. To study ion-beam induced modifications, Kapton foils were irradiated at the GSI linear accelerator UNILAC using several projectiles (e.g. Ti, Mo, Au, and U) within a large fluence regime (1 x 1010-5 x 1012 ions/cm2). The irradiated Kapton foils were analysed by means of infrared and UV/Vis spectroscopy, tensile strength measurement, mass loss analysis, and dielectric relaxation spectroscopy. For testing the radiation stability of Kapton at the cryogenic operation temperature (5-10 K) of the superconducting magnets, additional irradiation experiments were performed at the Grand Accelerateur National d' Ions Lourds (GANIL, France) focusing on the online analysis of the outgassing process of small volatile degradation fragments. The investigations of the electrical properties analysed by dielectric relaxation spectroscopy exhibit a different trend: high fluence irradiations with light ions (e.g. Ti) lead to a slight increase of the conductivity, whereas heavy ions (e.g. Sm, Au) cause a drastic change already in the fluence regime of nonoverlapping tracks (5 x 1010 ions/cm2). Online analysis of the outgassing process during irradiation at cryogenic temperatures shows the release of a variety of small gaseous molecules (e.g. CO, CO2, and short hydro carbons). Also a small amount of large polymer fragments is identified. The results allow the following conclusions which are of special interest for the application of Kapton as insulating material in a high-energetic particle radiation environment. a) The material degradation measured with the optical spectroscopy and tensile strength tests are scalable with the dose deposited by the ions. The high correlation of the results allows the prediction of the mechanical degradation with the simple and non-destructive infrared spectroscopy. The degradation curve points to a critical material degradation which has to be expected above a dose of 1 MGy. b) The dielectric relaxation spectroscopy indicates a dramatic increase in the conductivity induced by irradiation with heavy ions which pass a threshold of mass and deposited energy (dE/dx). The phenomenon indicates that only a few hits (fluences of 1010 ion/cm2) of a heavy high energetic ion leads to a significant increase of conductivity. c) The degradation induced formation of small molecules and their outgassing even at cryogenic temperature cause a gas release during irradiation. At temperatures below 20 K, an additional accumulation of these molecules in the bulk material occurs and leads to a critical gas evolution during heat-up cycles. (orig.)

  7. An implantable wireless neural interface for recording cortical circuit dynamics in moving primates

    Science.gov (United States)

    Borton, David A.; Yin, Ming; Aceros, Juan; Nurmikko, Arto

    2013-04-01

    Objective. Neural interface technology suitable for clinical translation has the potential to significantly impact the lives of amputees, spinal cord injury victims and those living with severe neuromotor disease. Such systems must be chronically safe, durable and effective. Approach. We have designed and implemented a neural interface microsystem, housed in a compact, subcutaneous and hermetically sealed titanium enclosure. The implanted device interfaces the brain with a 510k-approved, 100-element silicon-based microelectrode array via a custom hermetic feedthrough design. Full spectrum neural signals were amplified (0.1 Hz to 7.8 kHz, 200× gain) and multiplexed by a custom application specific integrated circuit, digitized and then packaged for transmission. The neural data (24 Mbps) were transmitted by a wireless data link carried on a frequency-shift-key-modulated signal at 3.2 and 3.8 GHz to a receiver 1 m away by design as a point-to-point communication link for human clinical use. The system was powered by an embedded medical grade rechargeable Li-ion battery for 7 h continuous operation between recharge via an inductive transcutaneous wireless power link at 2 MHz. Main results. Device verification and early validation were performed in both swine and non-human primate freely-moving animal models and showed that the wireless implant was electrically stable, effective in capturing and delivering broadband neural data, and safe for over one year of testing. In addition, we have used the multichannel data from these mobile animal models to demonstrate the ability to decode neural population dynamics associated with motor activity. Significance. We have developed an implanted wireless broadband neural recording device evaluated in non-human primate and swine. The use of this new implantable neural interface technology can provide insight into how to advance human neuroprostheses beyond the present early clinical trials. Further, such tools enable mobile

  8. Non-Contact Thermal Properties Measurement with Low-Power Laser and IR Camera System

    Science.gov (United States)

    Hudson, Troy L.; Hecht, Michael H.

    2011-01-01

    As shown by the Phoenix Mars Lander's Thermal and Electrical Conductivity Probe (TECP), contact measurements of thermal conductivity and diffusivity (using a modified flux-plate or line-source heat-pulse method) are constrained by a number of factors. Robotic resources must be used to place the probe, making them unavailable for other operations for the duration of the measurement. The range of placement is also limited by mobility, particularly in the case of a lander. Placement is also subject to irregularities in contact quality, resulting in non-repeatable heat transfer to the material under test. Most important from a scientific perspective, the varieties of materials which can be measured are limited to unconsolidated or weakly-cohesive regolith materials, rocks, and ices being too hard for nominal insertion strengths. Accurately measuring thermal properties in the laboratory requires significant experimental finesse, involving sample preparation, controlled and repeatable procedures, and, practically, instrumentation much more voluminous than the sample being tested (heater plates, insulation, temperature sensors). Remote measurements (infrared images from orbiting spacecraft) can reveal composite properties like thermal inertia, but suffer both from a large footprint (low spatial resolution) and convolution of the thermal properties of a potentially layered medium. In situ measurement techniques (the Phoenix TECP is the only robotic measurement of thermal properties to date) suffer from problems of placement range, placement quality, occupation of robotic resources, and the ability to only measure materials of low mechanical strength. A spacecraft needs the ability to perform a non-contact thermal properties measurement in situ. Essential components include low power consumption, leveraging of existing or highly-developed flight technologies, and mechanical simplicity. This new in situ method, by virtue of its being non-contact, bypasses all of these problems. The use of photons to both excite and measure the thermal response of any surface material to a high resolution (estimated footprint = 10 square centimeters) is a generational leap in physical properties measurements. The proposed method consists of spot-heating the surface of a material with a low (less than 1 W) power laser. This produces a moderate (5-10 K) temperature increase in the material.

  9. Fabrication and applications of nanocomposite structures using anodized aluminum oxide membranes

    Science.gov (United States)

    Gapin, Andrew Isaac

    As the field of nanotechnology continues to advance and device feature sizes scale down to ever smaller dimensions, it is becoming increasingly important to develop quick and efficient methods for large-scale production at the nanoscale. Creating such a template would have widespread uses in areas such as magnetic data storage, chemical sensors, and mask technology. One promising approach to realizing this goal may lie in utilizing the self-ordering behavior found in porous anodized aluminum oxide (AAO). This material offers many advantages such as the ability to customize the pore diameter and spacing and easy device integration based on its compatibility with silicon substrates. The pores of the AAO templates can be filled with many different materials via electrochemical deposition or other methods to produce numerous potential devices. In this work, current research results detailing the fabrication of AAO templates and their use in creating ˜100 nm tall CoPt, Ni, and composite Ni/CoPt nanowires is demonstrated. The synthesis of such nanostructures may ultimately be advantageous for new types of patterned magnetic recording media. The Ni nanowires exhibit relatively soft magnetic coercivity of 242 Oe, while the CoPt nanowires show a very high coercivity of at least 10.97 kOe, measured in the perpendicular direction along the nanowires axis. The composite soft magnet/hard magnet Ni/CoPt nanowires exhibit intermediate perpendicular coercivities depending on the relative amounts of Ni and CoPt. The Ni 80nm/CoPt20nm nanowires showed a coercivity of 1.96 kOe, the Ni50nm/CoPt50nm nanowires had a coercivity of 3.59 kOe, and the Ni20nm/CoPt80nm nanowires had a coercivity of 5.10 kOe. This marked decrease in the coercivity is significant because it could facilitate easier magnetic data writing. Analysis of the magnetic properties of the various nanowire structures and their dependence on the processing parameters is presented. A method for utilizing the AAO structure to replicate a master stamp for nanoimprinting technology is also discussed. In addition, plans for future work and a discussion of the application of these fabricated structures towards magnetic recording technology are presented.

  10. Effects of Medium,NPK Proportion and Nitrogen Concentration on Vegetative Growth of Oncidium%基质、氮磷钾比例和氮肥浓度对文心兰生长的影响

    Institute of Scientific and Technical Information of China (English)

    刘晓荣; 廖飞雄; 王碧青; 徐晔春

    2011-01-01

    为提高文心兰的栽培管理水平,为合理施肥提供参考依据,以文心兰切花品种'黄金二号'为试验材料,对不同基质、不同氮磷钾配比及氮肥浓度3个因素进行组合筛选.试验结果显示,水苔与木炭等比例混合基质有利于促进一年生文心兰植株生长,与对照相比,对次代新芽生长达到显著性差异.有利于芽高生长发育的组合是水苔+木炭(1:1),氮磷钾施肥比例30:10:10,氮肥浓度200 mg/L;假球茎发育阶段以水苔+木炭(1:1),氮磷钾施肥比例20:20:20,氮肥浓度100 mg/L为最好;次代新芽以水苔+木炭(1:1),氮磷钾肥比例为20:20:20,氮肥浓度为200 mg/L时生长好.%In order to improve cultivation management level and provide reference for fertilization of Oncidium reasonably, research was conducted to investigate the interaction of different medium, NPK Proportion and nitrogen concentration combinations on growth of ‘ Oncidium Goldiana × O. Guiena Gold’. Plants grown in the sphagnum moss: charcoal (1:1) promoted shoot, pseudobulb and significantly enhanced secondary shoot growth.Combinations of sphagnum moss: charcoal (1:1), 30 N:10 P2O5:10 K2O and 200 mg/L nitrogen accelerated shoot growth. While giving combinations of sphagnum moss: charcoal(1:1), 20 N:20 P2O5:20 K2O and 100 mg/L nitrogen boosted pseudobulb growth, at the same time enhanced secondary shoot growth only increasing nitrogen from 100 mg/L to 200 mg/L.

  11. Characterization of radiation modified κ-carrageenan oligomers for bio-based materials development

    International Nuclear Information System (INIS)

    κ-carrageenan oligomers are known to have several biological activities such as anti-HIV, anti-herpes, antitumor and antioxidant properties. Recent progress in the development of radiation modified κ-carrageenan has resulted in new applications such as plant growth promoter, radiation dose indicator and hydrogels for wound dressing. This presentation would touch on the changes in chemical structure, gelation and conformational transition behavior and molecular size of κ-carrageenan at doses from 0 to 200 kGy and would be correlated to these functions for the development of bio-based materials. Chemical and spectral analyses were carried out using UV-Vis spectroscopy, FT-IR spectroscopy, NMR spectroscopy, reducing sugar analysis, free sulfate and carboxylic acid analysis. The chemical and spectral analyses of the radiolytic products indicated increasing reducing sugars, carbonyl, carboxylic acids, and sulfates with increasing doses which reached a maximum level at a certain dose depending on the irradiation condition. Values were very much lower in solid irradiation (in vacuum and in air) as compared to aqueous irradiation. NMR data also revealed an intact structure of the oligomer irradiated at 100 kGy in the specific fraction that contains an Mw = (3-10) kDa. κ-carrageenan oligomers exhibited antioxidant properties as determined by hydroxyl radical scavenging activity, reducing power and DPPH radical scavenging capacity assay. The degree of oxidative inhibition increased with increasing dose which can be attributed to higher reducing sugar. Dynamic light scattering (DLS) experiments showed that a dose of up to 50 kGy, sol-gelation transition was still observed. Beyond 50 kGy, no gelation took place, instead appearance of fast relax-carrageenan mode in characteristic decay time function was observed at doses of (75-150) kGy. Optimum peak intensity was found at 100 kGy (mol wt. 5-10 kDa) which coincides with the optimum plant growth promoter effect in κ-carrageenan. At a dose beyond 150 kGy, the conformational transition temperature from coil to helix was no longer observed. The data obtained can give a wide spectrum of the possible uses of radiation modified κ-carrageenan for bio-based material development. (author)

  12. Study of the degradation process of polyimide induced by high energetic ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Severin, Daniel

    2008-09-19

    The dissertation focuses on the radiation hardness of Kapton under extreme radiation environment conditions. To study ion-beam induced modifications, Kapton foils were irradiated at the GSI linear accelerator UNILAC using several projectiles (e.g. Ti, Mo, Au, and U) within a large fluence regime (1 x 10{sup 10}-5 x 10{sup 12} ions/cm{sup 2}). The irradiated Kapton foils were analysed by means of infrared and UV/Vis spectroscopy, tensile strength measurement, mass loss analysis, and dielectric relaxation spectroscopy. For testing the radiation stability of Kapton at the cryogenic operation temperature (5-10 K) of the superconducting magnets, additional irradiation experiments were performed at the Grand Accelerateur National d' Ions Lourds (GANIL, France) focusing on the online analysis of the outgassing process of small volatile degradation fragments. The investigations of the electrical properties analysed by dielectric relaxation spectroscopy exhibit a different trend: high fluence irradiations with light ions (e.g. Ti) lead to a slight increase of the conductivity, whereas heavy ions (e.g. Sm, Au) cause a drastic change already in the fluence regime of nonoverlapping tracks (5 x 10{sup 10} ions/cm{sup 2}). Online analysis of the outgassing process during irradiation at cryogenic temperatures shows the release of a variety of small gaseous molecules (e.g. CO, CO{sub 2}, and short hydro carbons). Also a small amount of large polymer fragments is identified. The results allow the following conclusions which are of special interest for the application of Kapton as insulating material in a high-energetic particle radiation environment. a) The material degradation measured with the optical spectroscopy and tensile strength tests are scalable with the dose deposited by the ions. The high correlation of the results allows the prediction of the mechanical degradation with the simple and non-destructive infrared spectroscopy. The degradation curve points to a critical material degradation which has to be expected above a dose of 1 MGy. b) The dielectric relaxation spectroscopy indicates a dramatic increase in the conductivity induced by irradiation with heavy ions which pass a threshold of mass and deposited energy (dE/dx). The phenomenon indicates that only a few hits (fluences of 10{sup 10} ion/cm{sup 2}) of a heavy high energetic ion leads to a significant increase of conductivity. c) The degradation induced formation of small molecules and their outgassing even at cryogenic temperature cause a gas release during irradiation. At temperatures below 20 K, an additional accumulation of these molecules in the bulk material occurs and leads to a critical gas evolution during heat-up cycles. (orig.)

  13. Identifying and Mapping Seasonal Surface Water Frost with MGS TES

    Science.gov (United States)

    Bapst, J.; Bandfield, J. L.; Wood, S. E.

    2013-12-01

    The Thermal Emission Spectrometer (TES) visible/near-infrared and thermal infrared bolometers measured surface broadband albedo and temperature for more than three Mars years. As seasons progress on Mars, surface temperatures may fall below the frost point of volatiles in the atmosphere (namely, carbon dioxide and water). Systematic mapping of the spatial and temporal occurrence of these volatiles in the martian atmosphere, on the surface, and in the subsurface has shown their importance in understanding the climate of Mars. However, few studies have investigated seasonal surface water frost and its role in the global water cycle. We examine zonally-averaged TES daytime albedo, temperature, and water vapor abundance data [after Smith, 2004] to map the presence of surface water frost on Mars. Surface water frost occurs in the polar and mid latitudes, in regions with surface temperatures less than 220 K and above 150 K, and can significantly increase albedo relative to the bare surface. In the northern hemisphere water frost is most apparent in late fall/early winter, before the onset of carbon dioxide frost. Dust storms occurring near northern winter solstice affect albedo data and prevent us from putting a latitudinal lower limit on the water frost in the northern hemisphere. Regardless, seasonal water frost occurs at least as low as 48°N in Utopia Planitia, beginning at Ls=~230°, as observed by Viking Lander 2 [Svitek and Murray, 1990]. Daytime surface water frost was also observed at the Phoenix Lander site (68°N) beginning at Ls=~160° [Cull et al., 2010]. The timing of albedo variations observed by TES agree relatively well with lander observations of seasonal frost. Seasonal water frost is not detected during fall in the southern hemisphere. A potential explanation for this discrepancy, compared with frost detections in the north, is the disparity in atmospheric water vapor abundance between the two hemispheres. The frost point temperatures for water vapor in the southern hemisphere are ~5-10 K lower for the corresponding season and latitude in the north [Smith, 2004]. This inhibits the stability of water frost on the surface in the southern hemisphere and also lowers the maximum thickness of a water frost layer, potentially limiting its effect on surface albedo. Our work here shows that the seasonal progression in the northern hemisphere of Mars involves extensive deposition of water frost, similar in progression to the carbon dioxide seasonal ice cap. This behavior results in variation of surface albedo and therefore affects surface and subsurface temperatures, which could impact the distribution of ground ice. Surface frost and subsequent mixing of vapor back into the atmosphere likely plays an important role in the global water cycle. Mapping of water frost's geographical extent, timing, and impact on surface albedo can provide insight into the processes controlling the present Martian climate. References: Cull, S. et al. (2010) JGR, 115, E00E19. Smith, M. D. (2004) Icarus, 167, 148-165. Svitek, T. and Murray, B. (1990) JGR, 95(B2), 1495-1510.

  14. Thermal structure and CO distribution for the Venus mesosphere/lower thermosphere: 2001-2009 inferior conjunction sub-millimeter CO absorption line observations

    Science.gov (United States)

    Clancy, R. Todd; Sandor, Brad J.; Moriarty-Schieven, Gerald

    2012-02-01

    Sub-millimeter 12CO (346 GHz) and 13CO (330 GHz) line absorptions, formed in the mesosphere and lower thermosphere of Venus (70-120 km), have been mapped across the nightside Venus disk during 2001-2009 inferior conjunctions, employing the James Clerk Maxwell Telescope (JCMT). Radiative transfer analysis of these thermal line absorptions supports temperature and CO mixing profile retrievals, as well as Doppler wind fields (described in the companion paper, Clancy et al., 2012). Temporal sampling over the hourly, daily, weekly and interannual timescales was obtained over 2001-2009. On timescales inferred as several weeks, we observe changes between very distinctive CO and temperature nightside distributions. Retrieved nightside CO, temperature distributions for January 2006 and August 2007 observations display strong local time, latitudinal gradients consistent with early morning (2-3 am), low-to-mid latitude (0-40NS) peaks of 100-200% in CO and 20-30 K in temperature. The temperature increases are most pronounced above 100 km altitudes, whereas CO variations extend from 105 km (top altitude of retrieval) down to below 80 km in the mesosphere. In contrast, the 2004 and 2009 periods of observation display modest temperature (5-10 K) and CO (30-60%) increases, that are centered on antisolar (midnight) local times and equatorial latitudes. Doppler wind derived global (zonal and should be SSAS) circulations from the same data do not exhibit variations correlated with these CO, temperature short-term variations. However, large-scale residual wind fields not fit by the zonal, SSAS circulations are observed in concert with the strong temperature, CO gradients observed in 2006 and 2007 (Clancy et al., 2010). These short term variations in nightside CO, temperature distributions may also be related to observed nightside variations in O 2 airglow (Hueso, H., Sánchez-Lavega, A., Piccioni, G., Drossart, P., Gérard, J.C., Khatuntsev, I., Zasova, L., Migliorini, A. [2008]. J. Geophys. Res. 113, E00B02. doi:10.1029/2008JE003081) and upper mesospheric SO and SO 2 layers (Sandor, B.J., Clancy, R.T., Moriarty-Schieven, G.H., Mills, F.P. [2010]. Icarus 208, 49-60). The retrieved temperature profiles also exhibit 20 K long-term (2001-2009) variations in nightside (whole disk) average mesospheric (80-95 km) temperatures, similar to 1982-1991 variations identified in previous millimeter CO line observations (Clancy et al., 1991). Global average diurnal variations in lower thermospheric temperatures and mesospheric CO abundances decreased by a factor-of-two between 2000-2002 versus 2007-2009 periods of combined dayside and nightside observations. The infrequency and still limited temporal extent of the observations make it difficult to assign specific timescales to such longer term variations, which may be associated with longer term variations observed for cloud top SO 2 (Esposito, L.W., Bertaux, J.-L., Krasnopolsky, V., Moroz, V.I., Zasova, L.V. [1997]. Chemistry of lower atmosphere and clouds. In: Bougher, S.W., Hunten, D.M., Phillips, R.J. (Eds.), VENUS II, 1362pp) and mesospheric water vapor (Sandor, B.J., Clancy, R.T. [2005]. Icarus 177, 129-143) abundances.

  15. Crystal growth of hexaferrite architecture for magnetoelectrically tunable microwave semiconductor integrated devices

    Science.gov (United States)

    Hu, Bolin

    Hexaferrites (i.e., hexagonal ferrites), discovered in 1950s, exist as any one of six crystallographic structural variants (i.e., M-, X-, Y-, W-, U-, and Z-type). Over the past six decades, the hexaferrites have received much attention owing to their important properties that lend use as permanent magnets, magnetic data storage materials, as well as components in electrical devices, particularly those operating at RF frequencies. Moreover, there has been increasing interest in hexaferrites for new fundamental and emerging applications. Among those, electronic components for mobile and wireless communications especially incorporated with semiconductor integrated circuits at microwave frequencies, electromagnetic wave absorbers for electromagnetic compatibility, random-access memory (RAM) and low observable technology, and as composite materials having low dimensions. However, of particular interest is the magnetoelectric (ME) effect discovered recently in the hexaferrites such as SrScxFe12-xO19 (SrScM), Ba2--xSrxZn 2Fe12O22 (Zn2Y), Sr4Co2Fe 36O60 (Co2U) and Sr3Co2Fe 24O41 (Co2Z), demonstrating ferroelectricity induced by the complex internal alignment of magnetic moments. Further, both Co 2Z and Co2U have revealed observable magnetoelectric effects at room temperature, representing a step toward practical applications using the ME effect. These materials hold great potential for applications, since strong magnetoelectric coupling allows switching of the FE polarization with a magnetic field (H) and vice versa. These features could lead to a new type of storage devices, such as an electric field-controlled magnetic memory. A nanoscale-driven crystal growth of magnetic hexaferrites was successfully demonstrated at low growth temperatures (25--40% lower than the temperatures required often for crystal growth). This outcome exhibits thermodynamic processes of crystal growth, allowing ease in fabrication of advanced multifunctional materials. Most importantly, the crystal growth technique is considered theoretically and experimentally to be universal and suitable for the growth of a wide range of diverse crystals. In the present experiment, the conical spin structure of Co2Y ferrite crystals were a found to give rise to an intrinsic magnetoelectric effect. Our experiment reveals a remarkable increase in the conical phase transition temperature by ~150 K for Co 2Y ferrite, compared to 5--10 K of Zn2Y ferrites recently reported. The high quality Co2Y ferrite crystals, having low microwave loss and magnetoelectricity, were successfully grown on wide bandgap semiconductor GaN. The demonstration of the nanostructure materials-based "system on a wafer" architecture is a critical milestone to next generation microwave integrated systems. It is also practical that future microwave integrated systems and their magnetic performances could be tuned by an electric field because of the magnetoelectricity of hexaferrites.