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Sample records for patch tests

  1. Patch tests*

    PubMed Central

    Lazzarini, Rosana; Duarte, Ida; Ferreira, Alessandra Lindmayer

    2013-01-01

    Patch tests were introduced as a diagnostic tool in the late nineteenth century. Since then, they have improved considerably becoming what they are today. Patch tests are used in the diagnostic investigation of contact dermatitis worldwide. Batteries or series previously studied and standardized should be used in patch testing. The methodology is simple, but it requires adequate training for the results to be correctly interpreted and used. Despite having been used for over a century, it needs improvement like all other diagnostic techniques in the medical field. PMID:24474094

  2. Patch Test Negative Generalized Dermatitis.

    PubMed

    Spiker, Alison; Mowad, Christen

    2016-01-01

    Allergic contact dermatitis is a common condition in dermatology. Patch testing is the criterion standard for diagnosis. However, dermatitis is not always caused by an allergen, and patch testing does not identify a culprit in every patient. Generalized dermatitis, defined as eczematous dermatitis affecting greater than 3 body sites, is often encountered in dermatology practice, especially patch test referral centers. Management for patients with generalized dermatitis who are patch test negative is challenging. The purpose of this article is to outline an approach to this challenging scenario and summarize the paucity of existing literature on patch test negative generalized dermatitis.

  3. The "edge effect" with patch test materials.

    PubMed

    Fyad, A; Masmoudi, M L; Lachapelle, J M

    1987-03-01

    A positive "edge effect", i.e., the accumulation on the skin of a chemical solution (such as fluorescein 0.01% in a 50/50 water-ethanol solution) at the periphery of the patch test sites has been demonstrated. It occurs with different test materials (Finn Chamber; Silver Patch Test; Patch Test Chamber). Practical implications are discussed: this observation could be important when discussing results of laboratory investigations. In clinical practice, it could explain the occurrence of "ring-shaped" positive allergic patch test reactions to chemicals used in solution, i.e., Kathon CG or hydrocortisone.

  4. [Glossodynia--indication for patch testing?].

    PubMed

    Bäurle, G; Schönberger, A

    1986-08-15

    100 patients suffering from glossodynia without pathologic changes of the oral mucosa and 16 patients with suspected allergic contact stomatitis underwent patch testing using standard patch test and dental materials. The results were compared with those of patients in dental occupations suffering from hand eczema. As there is no clinical relevance of allergens in patients with glossodynia, patch testing seems to be unnecessary. On the other hand, patch test results of patients with stomatitis and dentures often suggest a causal allergy. In most of those cases, this was confirmed by complete healing after changing the denture bases, whereas in glossodynia such replacements never brought about a convincing improvement of the symptoms.

  5. A Practical Guide to Patch Testing.

    PubMed

    Fonacier, Luz

    2015-01-01

    Contact dermatitis is a common disease seen by allergists, dermatologists, and primary care physicians. The gold standard for diagnosing allergic contact dermatitis (ACD) is patch testing and is indicated in any patient with a chronic, pruritic, eczematous, or lichenified dermatitis if underlying or secondary ACD is suspected. Patients with acute generalized dermatitis who have extensive eczema on the back, are on immunosuppressant medications, and have applied topical corticosteroids, topical calcineurin inhibitors, or ultraviolet radiation to the patch test (PT) site may have suppressed PT reactions. The procedure of patch testing is not a difficult one to perform, but the interpretation of the PT needs some critical components, including having an appropriate level of suspicion for the diagnosis of ACD, testing the relevant allergens in their proper vehicle and concentration, and the necessary experience to properly interpret the results. Careful history and physical examination must be correlated with the result of the PT to establish clinical relevance. Once the PT is completed, allergens are identified, and relevance has been established, educating the patient about the avoidance of exposure is critical. The Joint Task Force of the American Academy of Allergy, Asthma and Immunology and American College of Allergy, Asthma and Immunology has developed updated practice parameters for contact dermatitis and patch testing, and their recommendations will be discussed (Fonacier LF, Bernstein DI, Pacheco K, Holness DL. Contact dermatitis: a practice parameter update 2015. J Allergy Clin Immunol Pract 2015; 3(3S):S1-S40.).

  6. Patch testing for noncontact dermatitis: the atopy patch test for food and inhalants.

    PubMed

    Wollenberg, Andreas; Vogel, Sandra

    2013-10-01

    The atopy patch test (APT) is defined as a patch test procedure to assess delayed type hypersensitivity reactions against those protein allergens known to elicit IgE-mediated type I reactions in atopic patients. This patch test procedure uses intact protein allergens instead of haptens in an optimized test setting and with a special reading key. It may be clinically useful especially for atopic dermatitis, as the currently available test procedures either target the wrong reaction type (type I and not type IV) or use the wrong allergens (haptens and not protein allergen). A positive APT reaction correlates with a positive lymphocyte transformation test and allergen-specific Th2 cells in the peripheral blood. As even small changes in the test procedure influence the sensitivity, specificity, and reproducibility of the APT, the European Task Force on Atopic Dermatitis (ETFAD) has developed a standardized APT technique: Intact protein allergens, purified in petrolatum, are applied in 12-mm-diameter Finn chambers mounted on Scanpor tape for 48 h to non-irritated, non-abraded, or tape-stripped skin of the upper back for 48 h; the evaluation of the test reaction is done after 48 and 72 h using the ETFAD reading key, assessing erythema as well as number and distribution pattern of the papules. The APT may reveal type IV sensitization in patients who are negative for the respective type I tests. Limited availability of the expensive test substances and limited reimbursement is among the factors restricting the routine use of the APT.

  7. Unusual edge effect in patch testing with silver nitrate.

    PubMed

    Iliev, D; Elsner, P

    1998-03-01

    Silver nitrate is a widely used substance and has been applied topically for cauterizing bleeding and healing wounds. In the past it has even been used to mark patch test sites, when no one knew that the substance itself might be a sensitizer. However, there are also toxic reactions to that substance. We report a case in which a positive "edge effect" at the periphery of the patch test site could be shown. It can be explained by the unequal distribution of patch test solutions in the different patch test systems with a concentration at the rim. Distinguishing between allergic and toxic reactions may be difficult when an edge effect occurs. Therefore, in certain rare cases a biopsy or a lymphocyte transformation test might be of help.

  8. Dermatotoxicologic clinical solutions: textile dye dermatitis patch testing.

    PubMed

    Coman, Garrett; Blickenstaff, Nicholas; Edwards, Ashley; Maibach, Howard

    2015-03-01

    The authors provide a framework for working up and counseling a patient with suspected textile dermatitis, focusing on identifying which textile materials are most likely to be the cause of the eczematous lesions, the current clinical guidelines, the utility and appropriateness of patch testing, the limitations of these guidelines, and our pro tempore recommendations. While there are many challenges to correctly identify and counsel patients on how to avoid the offending textile products in a patient with suspected textile dye dermatitis, there is value in following the guidelines set forth to help identify the causative textile(s). Although patch tests can be useful, dermatologists should understand the limitations of standardized patch testing for patients with suspected textile dye-induced dermatitis. These guidelines are expected to increase the likelihood of identifying the causative textile(s), so that patch testing can be supplemented with swatch testing and chemical dye extraction to help discover the allergenic dye.

  9. Membrane Vibration Tests Using Surface-Bonded Piezoelectric Patch Actuation

    NASA Technical Reports Server (NTRS)

    Gasper, James L.; Pappa, Richard S.

    2003-01-01

    This paper describes the status of on-going work at the NASA Langley Research Center to measure the dynamics of thin membranes. The test article is a one-meter square pre-tensioned Kapton membrane that incorporates small surface-bonded piezoelectric patches strategically positioned to excite many modes. It is shown that PVDF (polyvinylidene fluoride) and MFC (macro fiber composite) piezoelectric patch actuators provide adequate excitation energy to obtain modal frequencies and mode shapes. Results from modal tests performed on the membrane using piezoelectric patches of different sizes and positions are discussed.

  10. Atopy patch testing for foods: a review of the literature.

    PubMed

    Edwards, Kathryn P; Martinez, Barbara A

    2014-01-01

    The atopy patch test (APT) was first reported in 1895 by the German dermatologist, Jadassohn and was used for evaluation of contact dermatitis. The first documented epicutaneous application of aeroallergens was by Rostenberg and Sulzbergen in 1937. Although others including Mitchell and Platts-Mills, further described patch testing with aeroallergens, Langeland et al. initially described the use of patch testing with foods by testing atopic patients against egg white. Subsequently, food patch testing has gained popularity and has been included as a potential test to assess for food allergy not only for atopic dermatitis (AD) but also eosinophilic esophagitis and food protein-induced enterocolitis syndrome, although its role still remains unclear. Through a comprehensive literature review, this article addresses the use of APT for foods and its application in AD and other allergic diseases. There will be inclusion of some data from aeroallergen and hapten patch testing as a basis from which our knowledge for food APT is derived. The data, in particular the sensitivity, specificity, and predictive values, vary widely from 0 to 100%, depending on the study. Given this large variation in test results, food APT use in isolation is not recommended at this time. Additional studies are needed to standardize, improve accuracy and reproducibility, and determine its role in the evaluation of allergic diseases.

  11. Aeroallergen Patch Testing in Patients of Suspected Contact Dermatitis

    PubMed Central

    Bisen, Nelee; Shenoi, Shrutakirthi D; Balachandran, C

    2014-01-01

    Background: Aeroallergens are airborne substances present in the environment with the potential to trigger an allergic reaction in the respiratory tract, mucosae, or skin of susceptible individuals. The relevance of aeroallergens in the pathogenesis of atopic dermatitis has been reported by many investigators. However, very few studies have been conducted to investigate their role in the production of allergic contact dermatitis (ACD). Aims: To determine the prevalence of aeroallergen patch test positivity in patients of suspected ACD and to study the clinical characteristics of patients testing positive with aeroallergens. Materials and Methods: Patients presenting to our department with suspected contact allergy and undergoing patch testing with Indian Standard Series (ISS) between January 2010 and June 2011 were studied. After a detailed history and clinical examination, patients were patch tested with ISS and aeroallergen series. Based on the history and clinical suspicion, patients were additionally patch tested with 15% Parthenium. Prior tape stripping was done in some patients. Results: Out of total 114 patients, 26 (22.8%) showed sensitivity to aeroallergen series. Parthenium was the commonest aeroallergen being positive in all 26 patients followed by Xanthium in two. None reacted to other allergens. Although positivity was more in patients with prior tape stripping, the difference was not statistically significant. Conclusion: Most common aeroallergen found to be positive in our study was Parthenium hysterophorus. In view of low positivity to other allergens, routine aeroallergen patch testing in patients with suspected contact dermatitis may not be necessary. PMID:24891655

  12. Fixed drug eruption by etoricoxib confirmed by patch test*

    PubMed Central

    de Sousa, Aline Soares; Cardoso, José Carlos; Gouveia, Miguel Pinto; Gameiro, Ana Rita; Teixeira, Vera Barreto; Gonçalo, Maria

    2016-01-01

    Non-steroidal, anti-inflammatory drugs, followed by antibiotics, are the main causes of fixed drug eruption. They provoke one or several round erythematous or bullous lesions that recur in the same place after taking the causative medication. A positive patch test on residual, lesional skin can replace satisfactorily oral reintroduction. We describe the case of a 74-year-old woman with numerous, rounded, erythematous lesions on the trunk and recurrent blistering on the fifth right-hand finger, which developed a few hours after taking etoricoxib. Lesional patch testing with etoricoxib was positive and reproduced the typical pattern of a fixed drug eruption upon histopathology. We emphasize the specific reactivity of the etoricoxib patch test, and the capacity to reproduce the histologic pattern of the reaction. PMID:27828643

  13. Fixed drug eruption by etoricoxib confirmed by patch test.

    PubMed

    Sousa, Aline Soares de; Cardoso, José Carlos; Gouveia, Miguel Pinto; Gameiro, Ana Rita; Teixeira, Vera Barreto; Gonçalo, Maria

    2016-01-01

    Non-steroidal, anti-inflammatory drugs, followed by antibiotics, are the main causes of fixed drug eruption. They provoke one or several round erythematous or bullous lesions that recur in the same place after taking the causative medication. A positive patch test on residual, lesional skin can replace satisfactorily oral reintroduction. We describe the case of a 74-year-old woman with numerous, rounded, erythematous lesions on the trunk and recurrent blistering on the fifth right-hand finger, which developed a few hours after taking etoricoxib. Lesional patch testing with etoricoxib was positive and reproduced the typical pattern of a fixed drug eruption upon histopathology. We emphasize the specific reactivity of the etoricoxib patch test, and the capacity to reproduce the histologic pattern of the reaction.

  14. Photopatch and UV-irradiated patch testing in photosensitive dermatitis

    PubMed Central

    Rai, Reena; Thomas, Maria

    2016-01-01

    Background: The photopatch test is used to detect photoallergic reactions to various antigens such as sunscreens and drugs. Photosensitive dermatitis can be caused due to antigens like parthenium, fragrances, rubbers and metals. The photopatch test does not contain these antigens. Therefore, the Indian Standard Series (ISS) along with the Standard photopatch series from Chemotechnique Diagnostics, Sweden was used to detect light induced antigens. Aim: To detect light induced antigens in patients with photosensitive dermatitis. Methods: This study was done in a descriptive, observer blinded manner. Photopatch test and ISS were applied in duplicate on the patient's back by the standard method. After 24 hours, readings were recorded according to ICDRG criteria. One side was closed and other side irradiated with 14 J/cm2 of UVA and a second set of readings were recorded after 48 hrs. Result: The highest positivity was obtained with parthenium, with 18 out of 35 (51%) patients showing a positive patch test reaction with both photoallergic contact dermatitis and photoaggravation. Four patients (11%) showed positive patch test reaction suggestive of contact dermatitis to potassium dichromate and fragrance mix. Six patients had contact dermatitis to numerous antigens such as nickel, cobalt, chinoform and para-phenylenediamine. None of these patients showed photoaggravation on patch testing. Conclusion: Parthenium was found to cause photoallergy, contact dermatitis with photoaggravation and contact allergy. Hence, photopatch test and UV irradiated patch test can be an important tool to detect light induced antigens in patients with photosensitive dermatitis. PMID:26955581

  15. Investigation of contact allergy to dental materials by patch testing

    PubMed Central

    Rai, Reena; Dinakar, Devina; Kurian, Swetha S.; Bindoo, Y. A.

    2014-01-01

    Background: Dental products are widely used by patients and dental personnel alike and may cause problems for both. Dental materials could cause contact allergy with varying manifestations such as burning, pain, stomatitis, cheilitis, ulcers, lichenoid reactions localized to the oral mucosa in patients, and hand dermatitis in dental personnel. Patch testing with the dental series comprising commonly used materials can be used to detect contact allergies to dental materials. Aim: This study aimed to identify contact allergy among patients who have oral mucosal lesions after dental treatment and among dental personnel who came in contact with these materials. Materials and Methods: Twenty patients who had undergone dental procedures with symptoms of oral lichen planus, oral stomatitis, burning mouth, and recurrent aphthosis, were included in the study. Dental personnel with history of hand dermatitis were also included in the study. Patch testing was performed using Chemotechnique Dental Series and results interpreted as recommended by the International Contact Dermatitis Research Group (ICDRG). Results: Out of 13 patients who had undergone dental treatment/with oral symptoms, six patients with stomatitis, lichenoid lesions, and oral ulcers showed positive patch tests to a variety of dental materials, seven patients with ulcers had negative patch tests, seven dental personnel with hand dermatitis showed multiple allergies to various dental materials, and most had multiple positivities. Conclusion: The patch test is a useful, simple, noninvasive method to detect contact allergies among patients and among dental personnel dealing with these products. Long term studies are necessary to establish the relevance of these positive patch tests by eliminating the allergic substances, identifying clinical improvement, and substituting with nonallergenic materials. PMID:25165644

  16. DRESS Syndrome Following Levofloxacin Exposure With Positive Patch-test.

    PubMed

    Charfi, Ons; Lakhoua, Ghozlane; Sahnoun, Rim; Badri, Talel; Daghfous, Riadh; El Aidli, Sihem; Kastalli, Sarah; Zaïem, Ahmed

    2015-01-01

    Drug rash with eosinophilia and systemic symptoms (DRESS syndrome) in a severe cutaneous drug reaction, which can be life threatening. Levofloxacin has not been reported in literature as a causative drug. We are presenting an exceptional case of levofloxacin-induced DRESS without eosinophilia and with positive patch-tests to levofloxacin.

  17. Patch testing for allergic contact dermatitis in the allergist office.

    PubMed

    Fonacier, Luz; Charlesworth, Ernest N

    2003-07-01

    The identification of allergens responsible for allergic contact dermatitis (ACD) is key to the management of this disease. The patch test (PT) is the only safe, objective, scientific, and practical method for the diagnosis of ACD. There is no single PT panel that will screen all the relevant allergens in a patient's environment. It is generally thought that 20 to 30 allergens in routine screening tests can identify 50% to 70% of clinically relevant ACD. However, the usefulness of patch testing is enhanced with the number of allergens tested. Although the PT might be simple to apply, it might be difficult to read, interpret, and correlate to the patient's symptoms. A familiarity with the patient's environment, the process of the industry in that environment, and the uses of various chemicals in the industry is needed in most cases.

  18. Impulse Testing of Corporate-Fed Patch Array Antennas

    NASA Technical Reports Server (NTRS)

    Chamberlain, Neil F.

    2011-01-01

    This paper discusses a novel method for detecting faults in antenna arrays. The method, termed Impulse Testing, was developed for corporate-fed patch arrays where the element is fed by a probe and is shorted at its center. Impulse Testing was devised to supplement conventional microwave measurements in order to quickly verify antenna integrity. The technique relies on exciting each antenna element in turn with a fast pulse (or impulse) that propagates through the feed network to the output port of the antenna. The resulting impulse response is characteristic of the path through the feed network. Using an oscilloscope, a simple amplitude measurement can be made to detect faults. A circuit model of the antenna elements and feed network was constructed to assess various fault scenarios and determine fault-detection thresholds. The experimental setup and impulse measurements for two patch array antennas are presented. Advantages and limitations of the technique are discussed along with applications to other antenna array topologies

  19. Patch Test as a Diagnostic Tool in Hand Eczema

    PubMed Central

    Vigneshkarthik, Natarajan; Kuruvila, Sheela

    2016-01-01

    Introduction Allergic contact dermatitis is an important cause of hand eczema. Patch testing is the only investigation available to prove the diagnosis of allergic contact dermatitis. Exposures to allergens differ according to geographical, occupational, economic and social factors. Accordingly, patterns of allergic contact dermatitis differ in different parts of the world and different regions of the same country. Aim To study the causes of allergic contact dermatitis in adult patients with hand eczema with the help of patch testing. Materials and Methods This was a cross-sectional study involving 54 hand eczema patients conducted between October 2013 and June 2015, at a tertiary care centre in Southern India. After a detailed history including history of occupational exposure and detailed examination, patch test was done on these patients with Indian standard series. The patches were removed after 48 hours. Another reading was taken after 72 hours. The readings were interpreted according to International Contact Dermatitis Research Group criteria and noted down. The data were summarized using mean and standard deviation for continuous variables and percentages for categorical and dichotomous variables. The test of association was done with Fisher’s-exact test. Results Hyperkeratotic hand eczema was the commonest morphological type (29%), followed by discoid eczema. Pompholyx was significantly more common among patients with history of atopy. A total of 20 patients (37%) showed patch test positivity to a total of 25 allergens. Nickel was the most common allergen (11.11%) followed by para-phenylenediamine (PPD) (7.4%). Nickel (6 patients) and cobalt (3 patients) were the common allergens among women, while potassium dichromate (3 patients) and parthenium (2 patients) were the common allergens among men. Potassium dichromate allergy was significantly more common among masons and PPD allergy was significantly more common among hair dye users. Discoid pattern of

  20. Comparison of urine to sweat patch test results in court ordered testing.

    PubMed

    Levisky, J A; Bowerman, D L; Jenkins, W W; Johnson, D G; Levisky, J S; Karch, S B

    2001-10-15

    A former cocaine and methamphetamine abuser was continuously monitored with both sweat patch and urine testing for approximately 6 months. Thirteen sweat patches were applied and collected, five were positive for cocaine and/or methamphetamine, but all the urine specimens collected were negative at the analytical cut-off levels. The high incidence of false positive sweat patch tests in relation to the sensitivity, specificity, and efficiency of the sweat patch assay is discussed. Possible mechanisms, which can lead to false positive results, are presented. The results of our study raise further questions about the preferential use of the sweat patch in detecting new episodes of drug use in formerly chronic drug users.

  1. Evaluation of patch test results with denture material series.

    PubMed

    Gebhart, M; Geier, J

    1996-03-01

    791 patients, among them 59 dental technicians and 732 other patients, were tested with the denture material series (DMS) recommended by the German Contact Dermatitis Research Group (DKG) in the hospitals of the Information Network of Departments of Dermatology (IVDK) between January 1990 and July 1993. Most frequently, positive reactions occurred to cadmium chloride in both groups. However, there was no evidence at all for relevance of these reactions. Benzoyl peroxide (BPO) ranked 2nd in patch test positivity. Although not statistically significant, reactions were more frequent in dental technicians, who might be exposed to BPO the in working environment. Methyl methacrylate (MMA) and triethylene glycol dimethacrylate (TEGDMA) were common sensitizers in dental technicians but not in other patients. This finding, too, has its explanation in the working process of manufacturing dental prostheses.

  2. Priming and testing silicon patch-clamp neurochips.

    PubMed

    Py, Christophe; Denhoff, Michael W; Sabourin, Nicaulas; Weber, John; Shiu, Matthew; Zhao, Ping

    2014-09-25

    We report on the systematic and automated priming and testing of silicon planar patch-clamp chips after their assembly in Plexiglas packages and sterilization in an air plasma reactor. We find that almost 90% of the chips are successfully primed by our automated setup, and have a shunt capacitance of between 10 pF and 30 pF. Blocked chips are mostly due to glue invasion in the well, and variability in the manual assembly process is responsible for the distribution in shunt capacitance value. Priming and testing time with our automated setup is less than 5 min per chip, which is compatible with the production of large series for use in electrophysiology experiments.

  3. [Atopy patch test--when is it useful?].

    PubMed

    Toncić, Ruzica Jurakić; Lipozencić, Jasna

    2011-01-01

    The aim of the article is to introduce the atopy patch test (APT) as a model of cellular immunity reaction. APT is epicutaneous test performed with food and aeroallergens, and represents a good model for T lymphocyte hypersensitivity. It is compared with skin prick test (SPT). Its value is supported by the fact that atopic dermatitis is the result of complex immune interactions and involves both Coombs and Gell reactions type IV and I. In this review, we shortly discuss the etiopathogenesis of atopic dermatitis, distinction of extrinsic and intrinsic issues, and compare the value of APT with SPT and IgE determination. APT includes epicutaneous application of type I allergens known to elicit IgE mediated reactions, followed by evaluation of eczematous skin reaction after 48 and 72 hours. The limitations of ATP include the lack of test standardization, but there also are comparative advantages over SPT and specific IgE determination. We also briefly discuss the most important food and aeroallergens. APT has been recognized as a diagnostic tool in the evaluation of food allergy and aeroallergens such as house dust mite, pollen and animal dander. APT is a useful diagnostic procedure in patients with atopic dermatitis allergic to inhalant allergens and in children with food allergy younger than 2 years. The sensitivity and specificity of the test greatly depend on the allergen tested and patient age.

  4. Metal patch test results from 1990-2009.

    PubMed

    Nonaka, Hiromitsu; Nakada, Tokio; Iijima, Masafumi; Maibach, Howard I

    2011-03-01

    Although metals are common contact allergens, clinical findings of metal contact dermatitis have varied. Such patients have subsequently become rare in Japan as gold dermatitis caused by ear piercing or baboon syndrome by broken thermometers. To evaluate such clinical findings and to determine the frequency of metal allergy, we analyzed the results of patch testing with 18 metals from 1990-2009. Nine hundred and thirty-one patients (189 men and 742 women, mean age 39.0years [standard deviation±17.8]) were tested. Metals were applied on the back for 2days, and the results read with the International Contact Dermatitis Research Group (ICDRG) scoring system 3days after application. Reactions of + to +++ were regarded as positive. Differences of positive rates between men and women, and patients from 1990-1999 and those from 2000-2009 were analyzed with the χ(2) -test. Differences were considered significant at P<0.05. The metal to which the most patients reacted was 5% nickel sulfate (27.2%), irrespective of sex and phase. Significantly more women reacted to nickel sulfate (P<0.01), mercuric chloride (P<0.05) and gold chloride (P<0.01) than men. Significantly more patients in the 1990s reacted to palladium chloride, mercuric chloride and gold chloride (all P<0.01) than from 2000-2009. Nickel has been the most common metal allergen and mercury-sensitivity has decreased over 19years in Japan.

  5. The spectrum of cutaneous patch-test reactions in patients with atopic dermatitis.

    PubMed

    Hanifin, J M; Klas, P A

    1996-01-01

    We have outlined rationale and problems associated with three types of patch tests that may provide diagnostic help in patients with difficult-to-manage AD. Each of these methods is imperfect and in need of greater study using a critical approach, better techniques, more attention to irritant controls, and better definition of atopic populations. Proof of validity for aeroallergen patch testing will necessarily require large quantities of purified antigens. In spite of all these problems, patch testing can be useful and sometimes essential for the diagnosis and management of difficult AD.

  6. Patch-test reaction patterns in patients with a predisposition to atopic dermatitis.

    PubMed

    Brasch, Jochen; Schnuch, Axel; Uter, Wolfgang

    2003-10-01

    Patients with a predisposition to atopic dermatitis often need to be patch tested in order to detect possible contact sensitization. However, it is unknown whether immunologic or other peculiarities of atopic skin are related to altered patch-test reaction patterns. Our study was aimed at answering this question, because patch-test reaction patterns are of considerable practical importance in the reading and interpretation of patch tests. Therefore, we compared patterns of patch-test reactions in patients with a predisposition to atopic dermatitis and in control patients matched for sex, age, reason for testing and test centre. Patch-test results from 9 centres (2322 patients with a disposition to atopic dermatitis and 2126 matched controls) were evaluated retrospectively. All patients were tested with nickel sulfate, fragrance mix, potassium dichromate, lanolin alcohol, formaldehyde and mercury ammonium chloride. Patch tests applied for 1 day with readings on days 1, 2 and 3 were evaluated in order to cover the early phase of the reactions. Not unexpectedly, we found that, compared to the matched controls, patients with a predisposition to atopic dermatitis tended to have more doubtful and irritant reactions on day 1. As a new observation, it turned out that they had less reactions of crescendo pattern and more strong reactions on day 3. All these differences were slight/insignificant. A higher skin irritability in patients with a predisposition to atopic dermatitis is a likely explanation. In conclusion, standard methods for patch testing can be applied in patients with a predisposition to atopic dermatitis, but minor differences in reaction patterns should be considered.

  7. [Should metal alloy discs be used for patch testing in suspected metal implant intolerance reaction?].

    PubMed

    Thomas, P; Geier, J; Dickel, H; Diepgen, T; Hillen, U; Kreft, B; Schnuch, A; Szliska, C; Mahler, V

    2015-11-01

    Intolerance reactions to metal implants may be caused by metal allergy. However, prior to implantation, patch testing should not be done in a prophylactic-prophetic approach. Pre-implant patch testing should only be performed to verify or exclude metal allergy in patients with a reported respective history. In the case of implant-in particular arthroplasty-related complications like, for example, pain, effusion, skin changes, reduced range of motion, or loosening, orthopedic-surgical differential diagnostics should be performed first. Allergological workup of suspected metal implant allergy should be done with the DKG baseline series which contains nickel-, cobalt- and chromium-preparations. Various studies assessing the usefulness of metal alloy discs for patch testing proved that this approach does not give reliable information about metal allergy. Positive patch test reactions to the discs cannot be assigned to a specific metal within the disc alloy components. Furthermore, availability of such metal discs might be an invitation to uncritical testing. Accordingly, due to lack of benefit in comparison to patch testing with standardized metal salt preparations, we do not recommend patch testing with metal alloy discs.

  8. Assessment criteria for MEG/EEG cortical patch tests

    NASA Astrophysics Data System (ADS)

    Im, Chang-Hwan; An, Kwang-Ok; Jung, Hyun-Kyo; Kwon, Hyukchan; Lee, Yong-Ho

    2003-08-01

    To validate newly developed methods or implemented software for magnetoencephalography/electroencephalography (MEG/EEG) source localization problems, many researchers have used human skull phantom experiments or artificially constructed forward data sets. Between the two methods, the use of an artificial data set constructed with forward calculation attains superiority over the use of a human skull phantom in that it is simple to implement, adjust and control various conditions. Nowadays, for the forward calculation, especially for the cortically distributed source models, generating artificial activation patches on a brain cortical surface has been popularized instead of activating some point dipole sources. However, no well-established assessment criterion to validate the reconstructed results quantitatively has yet been introduced. In this paper, we suggest some assessment criteria to compare and validate the various MEG/EEG source localization techniques or implemented software applied to the cortically distributed source model. Four different criteria can be used to measure accuracy, degrees of focalization, noise-robustness, existence of spurious sources and so on. To verify the usefulness of the proposed criteria, four different results from two different noise conditions and two different reconstruction techniques were compared for several patches. The simulated results show that the new criteria can provide us with a reliable index to validate the MEG/EEG source localization techniques.

  9. Attitudes about Advances in Sweat Patch Testing in Drug Courts: Insights from a Case Study in Southern California

    ERIC Educational Resources Information Center

    Polzer, Katherine

    2010-01-01

    Drug courts are reinventing the drug testing framework by experimenting with new methods, including use of the sweat patch. The sweat patch is a band-aid like strip used to monitor drug court participants. The validity and reliability of the sweat patch as an effective testing method was examined, as well as the effectiveness, meaning how likely…

  10. Inferring local competition intensity from patch size distributions: a test using biological soil crusts

    USGS Publications Warehouse

    Bowker, Matthew A.; Maestre, Fernando T.

    2012-01-01

    Dryland vegetation is inherently patchy. This patchiness goes on to impact ecology, hydrology, and biogeochemistry. Recently, researchers have proposed that dryland vegetation patch sizes follow a power law which is due to local plant facilitation. It is unknown what patch size distribution prevails when competition predominates over facilitation, or if such a pattern could be used to detect competition. We investigated this question in an alternative vegetation type, mosses and lichens of biological soil crusts, which exhibit a smaller scale patch-interpatch configuration. This micro-vegetation is characterized by competition for space. We proposed that multiplicative effects of genetics, environment and competition should result in a log-normal patch size distribution. When testing the prevalence of log-normal versus power law patch size distributions, we found that the log-normal was the better distribution in 53% of cases and a reasonable fit in 83%. In contrast, the power law was better in 39% of cases, and in 8% of instances both distributions fit equally well. We further hypothesized that the log-normal distribution parameters would be predictably influenced by competition strength. There was qualitative agreement between one of the distribution's parameters (μ) and a novel intransitive (lacking a 'best' competitor) competition index, suggesting that as intransitivity increases, patch sizes decrease. The correlation of μ with other competition indicators based on spatial segregation of species (the C-score) depended on aridity. In less arid sites, μ was negatively correlated with the C-score (suggesting smaller patches under stronger competition), while positive correlations (suggesting larger patches under stronger competition) were observed at more arid sites. We propose that this is due to an increasing prevalence of competition transitivity as aridity increases. These findings broaden the emerging theory surrounding dryland patch size distributions

  11. Skin biopsy and quantitative sensory testing do not predict response to lidocaine patch in painful neuropathies.

    PubMed

    Herrmann, David N; Pannoni, Valerie; Barbano, Richard L; Pennella-Vaughan, Janet; Dworkin, Robert H

    2006-01-01

    Predictors of response to neuropathic pain treatment in patients with painful distal sensory neuropathies are lacking. The 5% lidocaine patch is believed to exert its effects on neuropathic pain via a local stabilizing effect on cutaneous sensory afferents. As such, it provides a model to assess whether the status of epidermal innervation as determined by skin biopsy or quantitative sensory testing (QST) of small- and large-diameter sensory afferents might serve as predictors of response to topical, locally active treatment. In this study we assessed associations between epidermal nerve fiber (ENF) densities, sensory nerve conduction studies (NCS), QST, and response to a 5% lidocaine patch in patients with painful distal sensory neuropathies. We observed no association between distal leg epidermal and subepidermal innervation and response to the lidocaine patch. Several patients with complete loss of distal leg ENF showed a response to the lidocaine patch. Similarly we observed no consistent association between treatment response and QST for vibration, cooling, warm, heat-pain, and cold-pain thresholds, or distal sensory NCS. Thus, distal-leg skin biopsy, QST, and sensory NCS cannot be used to identify patients with painful polyneuropathy likely to respond to a lidocaine patch in clinical practice. Further studies are required to clarify precisely the mechanism and site of action of the lidocaine patch in patients with peripheral neuropathic pain.

  12. Allergy to cocamidopropyl betaine may be due to amidoamine: a patch test and product use test study.

    PubMed

    Fowler, J F; Fowler, L M; Hunter, J E

    1997-12-01

    Cocamidopropyl betaine (CAPB) is an amphoteric surfactant commonly used in personal care products and surface cleaners. Patch testing with commercially-available CAPB has yielded occasional reactions indicative of allergic contact dermatitis. To determine if subjects with previous positive patch tests would react in provocative use tests of products containing CAPB, and to study various contaminants in commercial CAPB supplies for allergenicity in these subjects, 10 subjects previously positive to CAPB on patch testing used a hair shampoo, hand soap, and body wash containing CAPB for 1-6 weeks or until a reaction developed. Later, they were patch tested to 2 different purity grades of CAPB and 3 possible manufacturing contaminants (dimethylaminopropylamine, amidoamine, and sodium monochloroacetate). 7 of the 10 subjects developed dermatitis from 1 or more CAPB-containing products at some point during the study. 9 of the 10 use-test subjects were then patch tested, and 6 of these subjects showed a reaction to amidoamine (0.1% aq.). None reacted to dimethylaminopropylamine (0.1% pet.). 1 subject reacted to CAPB but not to amidoamine. In the follow-up patch testing with CAPB that was free of amidoamine, there were no positive reactions. Most subjects who were patch-test-positive showed a reaction when using CAPB-containing skin and hair care products. The chemical amidoamine, which is used in the synthesis of CAPB and which is a known contaminant of CAPB preparations, is likely to be the actual sensitizer in most cases rather than CAPB itself. The results do not rule out the possibility that CAPB itself may be an allergen in rare cases.

  13. Diagnosis and treatment of an oral base-metal contact lesion following negative dermatologic patch tests.

    PubMed

    Lyzak, W A; Flaitz, C M; McGuckin, R S; Eichmiller, F; Brown, R S

    1994-08-01

    We report a confirmed case of intraoral contact mucositis secondary to nickel dental alloy hypersensitivity. The lesion resolved after removal of the offending prosthesis. The patient responded negatively to dermatologic patch tests, but a positive intraoral rechallenge confirmed the mucositis diagnosis. A nonreactive, gold alloy prosthesis was inserted for a successful result.

  14. Hydroxychloroquine-induced acute generalized exanthematous pustulosis with positive patch-testing.

    PubMed

    Charfi, Ons; Kastalli, Sarrah; Sahnoun, Rym; Lakhoua, Ghozlane

    2015-01-01

    Acute generalized exanthematous pustulosis (AGEP) is a severe cutaneous adverse reaction, mostly induced by drugs. Hydroxychloroquine have been rarely reported in literature as a causative drug of this reaction. We report a case of AGEP induced by hydroxychloroquine with systemic involvement and confirmed by positive patch testing.

  15. Permeability test for transdermal and local therapeutic patches using Skin PAMPA method.

    PubMed

    Vizserálek, Gábor; Berkó, Szilvia; Tóth, Gergő; Balogh, Réka; Budai-Szűcs, Mária; Csányi, Erzsébet; Sinkó, Bálint; Takács-Novák, Krisztina

    2015-08-30

    Using the skin as absorption site presents unique advantages that have facilitated the progression of transdermal drug delivery in the past decades. Efforts in drug research have been devoted to find a quick and reproducible model for predicting the skin permeation of molecules. The Parallel Artificial Membrane Permeability Assay (PAMPA) has been extended for prediction of transdermal permeation by developing a model with completely artificial membrane, which can mimic the permeation through the stratum corneum. The present study aims to extend the Skin PAMPA method for testing transdermal and local therapeutic patches. The original method was modified and seven commercially available transdermal and local therapeutic patches with four different active pharmaceutical ingredients (nicotine, fentanyl, rivastigmine and ketoprofen) were studied. Data were compared to the declared delivery rates that are indicated by the manufacturers. Ex vivo permeation study was also performed in order to compare the permeated amount of the released drugs obtained by the two methods. The flux across the artificial membrane as well as the human skin (ex vivo) has been calculated and compared to the in vivo flux deduced from the labelled delivery rate and the active area of the patches. The results suggest that Skin PAMPA system can serve as a useful tool for evaluation and classification of the transdermal patches.

  16. The importance of checking for delayed reactions in pediatric patch testing.

    PubMed

    Matiz, Catalina; Russell, Kathryn; Jacob, Sharon E

    2011-01-01

    Patch testing is often performed with the final reading being completed at 72 hours. Studies in adults have shown that performing an additional reading several days later increases the yield of relevant positive reactions. We report a study of this matter in children. We conducted a prospective patch test study of 38 affected children aged 6 to 17 (mean 11.6 years), with presumed allergic contact dermatitis between April and July 2009. The patients were required to return at 48 hours for patch test removal and assessment of early reactions, at 72 to 96 hours (3-4 days) for evaluation of delayed reactions, and again at 168 to 216 hours (7-9 days) for a final late delayed reading. We tallied the number of patients with "equivocal" (+/?), +, ++, and +++ reactions and noted these as potential positive reactions by reading date. Twenty-five of the 38 children (66%) had a positive reaction at 48 hours; 32 children (84%) had a positive reaction at 72 hours (day 3); 19 children (50%) had a positive reaction at 168 to 216 hours (day 7-9). Of those 19, 16 (42%) had persistent reactions, while 5 children (13%) had new late delayed reactions. Among the new late delayed reactions, there were six allergens identified, four of which were considered of probable clinical relevance. When patch testing with Thin Layer Rapid-Use Epicutaneous test panels, a delayed reading beyond 72 hours may be needed to identify the offending agent(s) responsible for allergic contact dermatitis in some children. Additional studies are needed to assess optimal readings schedules.

  17. A clinical and patch test study in a tall-oil rosin factory.

    PubMed

    Färm, G; Lidén, C; Karlberg, A T

    1994-08-01

    Rosin of different sources is commonly used in many technical products and is known to cause contact allergy. The aim of the present investigation was to study the frequency of occupational dermatoses and of contact allergy to rosin in a factory producing tall-oil rosin. 163/180 present employees and 17/35 former employees participated in the study, which consisted of interview, clinical examination and patch testing with a standard series and additional rosins. 1/4 of those examined had some kind of current skin lesion. There were 10 cases of hand eczema. 7 subjects were patch-test-positive to gum rosin in the standard series. This frequency is about the same as among dermatitis patients at our clinic. Only 1 reaction to tall-oil rosin and none to the modified rosins tested were found. No relation between a positive patch test reaction to rosin and current skin disease could be established. No case of ongoing occupational skin disease was proved.

  18. Comparison of European Standard Patch Test Results of 330 Patients from an Occupational Diseases Hospital

    PubMed Central

    Aytekin, Aslı; Tutkun, Engin; Yılmaz, Hınç

    2016-01-01

    Background and Aim. Contact dermatitis (CD) is the most prevalent occupational skin disease with a significant impact on quality of life. Patch testing is used for the identification of responsible allergens which may improve protective and preventive measures in the workplace. Herein, we aim to identify the demographic characteristics and occupation of patients with early diagnosis of occupational CD and compare patch test results. Materials and Methods. The study included 330 patients referred to our clinic between April 2009 and April 2011 and who were patch-tested with 28-allergen European Standard Test. Results. 126 (38%) patients were female and 204 (62%) were male with a mean age of 36.12 (±13.13) years. Positive allergic reactions were observed in 182 (55%) patients. Nickel sulphate (41/126) and potassium dichromate (39/204) were significantly the most common allergens in women and men, respectively (P < 0.005). Additionally, the most common occupation in women was household activities (83/126) and in men was manufacturing (80/204). Conclusion. The allergens to which people become sensitized differ according to their working environment and occupation. Classification of occupations is important for identification of sensitization risks and monitoring of changes in allergen distribution of different occupations. PMID:27807445

  19. Clinical experience and patch testing using colophony (rosin) from different sources.

    PubMed

    Karlberg, A T; Lidén, C

    1985-10-01

    Patients with suspected allergy to colophony were patch-tested with colophony (rosin) of different kinds (gum rosin, tall oil rosin). More cases of allergy were detected by testing with more than one type of colophony. Tall oil rosin produced a smaller number of positive reactions than the gum rosins tested, which suggests a lower allergenic activity. Venice turpentine was a useful additional screening substance. When different test concentrations were compared (20% and 5%) the lower concentration failed to reveal four of 30 cases. The patients' eczema had been caused chiefly by contact with colophony in their work.

  20. Allergic contact dermatitis from exotic woods: importance of patch-testing with patient-provided samples.

    PubMed

    Podjasek, Joshua O; Cook-Norris, Robert H; Richardson, Donna M; Drage, Lisa A; Davis, Mark D P

    2011-01-01

    Exotic woods from tropical and subtropical regions (eg, from South America, south Asia, and Africa) frequently are used occupationally and recreationally by woodworkers and hobbyists. These exotic woods more commonly provoke irritant contact dermatitis reactions, but they also can provoke allergic contact dermatitis reactions. We report three patients seen at Mayo Clinic (Rochester, MN) with allergic contact dermatitis reactions to exotic woods. Patch testing was performed and included patient-provided wood samples. Avoidance of identified allergens was recommended. For all patients, the dermatitis cleared or improved after avoidance of the identified allergens. Clinicians must be aware of the potential for allergic contact dermatitis reactions to compounds in exotic woods. Patch testing should be performed with suspected woods for diagnostic confirmation and allowance of subsequent avoidance of the allergens.

  1. Patch-testing with serial dilutions of tixocortol pivalate and potential cross-reactive substances.

    PubMed

    Isaksson, M; Bruze, M; Goossens, A; Lepoittevin, J P

    2000-01-01

    Of patch-tested patients with dermatitis, 4-5% are allergic to corticosteroids. Four groups of corticosteroids are recognized (A-D), where substances from the same group may cross-react. We investigated the potential cross-reactivity pattern and dose-response relationship for several corticosteroids from group A. We also included the corresponding aldehyde to hydrocortisone, as this degradation product has been proposed to be immunogenic. Eleven patients shown to be allergic to tixocortol pivalate were patch-tested with several corticosteroids from group A, as well as with the aldehyde, all in serial dilutions. All 11 reacted to both tixocortol pivalate and hydrocortisone. The dose-response relationship for the corticosteroids tended to be similar to sensitizers lacking anti-inflammatory potential. Patients with simultaneous reactions to many substances had high patch-test reactivity to tixocortol pivalate and hydrocortisone, while patients with few such reactions showed low reactivity (p=0.001 and 0.003, respectively). Several patients reacted to the aldehyde, supporting the theory that it is an intermediate in sensitization.

  2. Comparison of Marketed Cosmetic Products Constituents with the Antigens Included in Cosmetic-related Patch Test

    PubMed Central

    Cheong, Seung Hyun; Choi, You Won; Myung, Ki Bum

    2010-01-01

    Background Currently, cosmetic series (Chemotechnique Diagnostics, Sweden) is the most widely used cosmetic-related patch test in Korea. However, no studies have been conducted on how accurately it reflects the constituents of the cosmetics in Korea. Objective We surveyed the constituents of various cosmetics and compare with the cosmetic series, to investigate whether it is accurate in determining allergic contact dermatitis caused by cosmetics sold in Korea. Methods Cosmetics were classified into 11 categories and the survey was conducted on the constituents of 55 cosmetics, with 5 cosmetics in each category. The surveyed constituents were classified by chemical function and compared with the antigens of cosmetic series. Results 155 constituents were found in 55 cosmetics, and 74 (47.7%) of constituents were included as antigen. Among them, only 20 constituents (27.0%) were included in cosmetic series. A significant number of constituents, such as fragrance, vehicle and surfactant were not included. Only 41.7% of antigens in cosmetic series were found to be in the cosmetics sampled. Conclusion The constituents not included in the patch test but possess antigenicity are widely used in cosmetics. Therefore, the patch test should be modified to reflect ingredients in the marketed products that may stimulate allergies. PMID:20711261

  3. Patch testing for allergic contact dermatitis to cigarettes: smoked/unsmoked components and formaldehyde factors.

    PubMed

    Carew, Benjamin; Muir, Jim

    2014-08-01

    A patient with hand dermatitis reported that switching her smoking hand resulted in reduced symptoms. When allergy to cigarettes is suspected the literature supports standard allergy testing as well as testing the individual components of cigarettes. Initial standard patch testing revealed an allergy to formaldehyde and the formaldehyde releasing agent, quaternium-15. The patient did not react to her usual roll-your-own cigarette components but reacted to the smoked filter paper of a particular brand of cigarette she frequently borrowed from a friend. Possible explanations include either a variation of ingredients between cigarettes that alters the formaldehyde concentration or another unidentified allergen in the branded cigarette causing allergic contact dermatitis.

  4. Test/analysis comparison of piezoelectric patch local behavior for vibroacoustic active control application

    NASA Astrophysics Data System (ADS)

    Florens, Corine; Balmes, Etienne; Clero, Franck

    2007-04-01

    To predict the effect of active control on aircraft or helicopter trim panels, made with honeycomb sandwich composite, one approach consists in modeling the panel by Finite Element Method. FEM with shell elements for the laminate and volume elements for the core is classically used in industry; in a previous study the homogenized modeling approach has been validated. The aim of the present paper is to make a test/analysis comparison of the dynamic behavior of a honeycomb core sandwich beam actuated by a piezoelectric patch. More precisely, the behavior in the vicinity of the piezoelectric actuator is characterized, in order to validate the modeling approach of honeycomb sandwich composite equipped with piezoelectric patches.

  5. [Contact allergens in the standard patch test series from 1980-2004 at the University Clinic Aachen].

    PubMed

    Hoeller Obrigkeit, D; Vens, N; Merk, H F; Schroeder, C M

    2005-12-01

    Allergic contact dermatitis is a common disease whose specific therapy is avoidance of allergens. It is critical to identify frequency of occurrence of allergic reactions to initiate preventive measures (e.g. elimination of substances with an especially high allergic potential). This study analyzes results of patch testing performed between 1980 and 1993 at the University Clinic of the RWTH Aachen. Additionally, age and sex-related distribution was evaluated. The data is compared to published patch test results covering the years 1995-2001 and patch test results from 2004 in the University Clinic Aachen.

  6. Testing metapopulation concepts: effects of patch characteristics and neighborhood occupancy on the dynamics of an endangered lagomorph

    USGS Publications Warehouse

    Eaton, Mitchell J.; Hughes, Phillip T.; Hines, James E.; Nichols, James D.

    2014-01-01

    Metapopulation ecology is a field that is richer in theory than in empirical results. Many existing empirical studies use an incidence function approach based on spatial patterns and key assumptions about extinction and colonization rates. Here we recast these assumptions as hypotheses to be tested using 18 years of historic detection survey data combined with four years of data from a new monitoring program for the Lower Keys marsh rabbit. We developed a new model to estimate probabilities of local extinction and colonization in the presence of nondetection, while accounting for estimated occupancy levels of neighboring patches. We used model selection to identify important drivers of population turnover and estimate the effective neighborhood size for this system. Several key relationships related to patch size and isolation that are often assumed in metapopulation models were supported: patch size was negatively related to the probability of extinction and positively related to colonization, and estimated occupancy of neighboring patches was positively related to colonization and negatively related to extinction probabilities. This latter relationship suggested the existence of rescue effects. In our study system, we inferred that coastal patches experienced higher probabilities of extinction and colonization than interior patches. Interior patches exhibited higher occupancy probabilities and may serve as refugia, permitting colonization of coastal patches following disturbances such as hurricanes and storm surges. Our modeling approach should be useful for incorporating neighbor occupancy into future metapopulation analyses and in dealing with other historic occupancy surveys that may not include the recommended levels of sampling replication.

  7. Analysis of skin patch test results and metalloproteinase-2 levels in a patient with contact dermatitis

    PubMed Central

    Czajkowski, Rafał; Kowaliszyn, Bogna; Żbikowska-Gotz, Magdalena; Bartuzi, Zbigniew

    2015-01-01

    Introduction The complex course of skin reactions that contact eczema involves is due in part to abnormalities of the extracellular matrix function. Proteins that degrade extracellular matrix components include metalloproteinases (MMP), which are divided into subcategories depending on the chemical structure and substrate specificity. Aim To analyse patch test results in contact dermatitis patients and to assess MMP-2 levels during skin lesion exacerbation and remission. Material and methods Fifty patients suffering from contact eczema were qualified to the study and 20 healthy volunteers as a control group. The study group patients had epidermal skin tests performed with the “European Standard” set. To assess the MMP-2 level in serum, venous blood was drawn, twice from study group patients – during contact dermatitis exacerbation and remission periods – and once from control group patients. Assessment of MMP-2 in serum was done with ELISA immunoassay. To verify the proposed hypotheses, parametric and nonparametric significance tests were used. Results Hands were the most frequent location of contact dermatitis. Nickel (II) sulphate was the most frequent sensitizing substance. Mean MMP-2 levels were statistically higher in the study group both in contact dermatitis exacerbation and remission periods than in the control group. There was no statistically significant difference between MMP-2 levels and skin patch test results. Conclusions Nickel is one of the most allergenic contact allergens in patients with contact dermatitis. Metalloproteinase-2 is a good marker of contact dermatitis in various stages of the disease. PMID:26161054

  8. Patch-test results in children and adolescents: systematic review of a 15-year period*

    PubMed Central

    Rodrigues, Dulcilea Ferraz; Goulart, Eugênio Marcos Andrade

    2016-01-01

    The number of studies on patch-test results in children and adolescents has gradually increased in recent years, thus stimulating reviews. This paper is a systematic review of a 15-year period devoted to studying the issue. Variations pertaining to the number and age groups of tested children and/or adolescents, the number of subjects with atopy/atopic dermatitis history, the quantity, type and concentrations of the tested substances, the test technique and type of data regarding clinical relevance, must all be considered in evaluating these studies, as they make it harder to formulate conclusions. The most common allergens in children were nickel, thimerosal, cobalt, fragrance, lanolin and neomycin. In adolescents, they were nickel, thimerosal, cobalt, fragrance, potassium dichromate, and Myroxylon pereirae. Knowledge of this matter aids health professionals in planning preventive programs aimed at improving children's quality of life and ensuring that their future prospects are not undermined. PMID:26982781

  9. Patch testing with budesonide in serial dilutions: the significance of dose, occlusion time and reading time.

    PubMed

    Isaksson, M; Bruze, M; Goossens, A; Lepoittevin, J P

    1999-01-01

    Budesonide is advocated as a marker molecule for corticosteroid contact allergy. When patch testing corticosteroids, one must consider their sensitizing potential but also their anti-inflammatory properties, as well as the possibility of different time courses for such properties. The dose-response relationship for budesonide was therefore investigated with regard to dose, occlusion time, and reading time. 10 patients were patch tested with budesonide in ethanol in serial dilutions from 2.0% down to 0.0002% with occlusion times of 48, 24, and 5 h. Readings were on D2, D4, and D7. The 48-h occlusion picked up most positive reactors, 8/10. The D4 reading (48-h occlusion) detected most positive reactors, 8/10, and here 0.002% picked up most contact allergies. Late readings favoured high concentrations. The "edge effect" was noted for several concentrations at early readings. Due to the individual corticosteroid reactivity, the dose-response relationship and the time courses of the elicitation and the anti-inflammatory capacity, several features may be explained, i.e., that lower concentrations may detect budesonide allergy better at early readings, that patients with an "edge reaction" can have positive reactions to lower concentrations.

  10. Immunophenotyping of the cutaneous cellular infiltrate after atopy patch testing in cats with atopic dermatitis.

    PubMed

    Roosje, P J; Thepen, T; Rutten, V P M G; van den Brom, W E; Bruijnzeel-Koomen, C A F M; Willemse, T

    2004-10-01

    Cats with spontaneously occurring atopic dermatitis have clinical and immunocytochemical characteristics compatible with these in humans with atopic dermatitis (AD). The atopy patch test (APT) has proven to be a valuable tool in elucidating the disease process in humans. Additionally, the APT is very specific and bypasses the problem of conflicting results due to differences in chronicity of lesions of AD patients. We adapted the APT for use in cats to explore the suitability of the APT as a tool to study the onset of allergic inflammation in cats with atopic dermatitis. APT were performed in AD cats (n = 6) and healthy cats (n = 10). All cats were patch tested with two allergens in three different dilutions and a diluent control. The allergens for the APT were selected from positive intradermal test and /or prick test results and consisted of: Dermatophagoides farinae, D. pteronyssinus, Tyrophagus putrescentiae, and a grass pollen mixture. APT were read after 10, 24 and 48 h, and punch biopsies for immunohistochemical evaluation were collected at these time points. Macroscopically positive APT reactions were observed in three out of six cats at 24 and/or 48 h with allergen concentrations of 25,000 and 100,000 NU/ml. Reactions were not observed at negative control sites and neither in control animals. A significantly increased number of IL-4+, CD4+, CD3+, MHC class II+ and CD1a+ cells was found in one AD cat with positive APT reactions. Five out of six AD cats had significantly increased IL-4+ T cell numbers at 24 and/or 48 h. Our data indicate that in cats, macroscopically positive patch test reactions can be induced, which have a cellular infiltrate similar to that in lesional skin. We found a high specificity and a macroscopically positive APT reaction in half of the cats, which is similar to what is seen in humans. Hence, the APT in cats might be a useful tool in studying the immunopathogenesis of feline atopic dermatitis.

  11. Clutter sensitivity test under controlled field conditions Resonant Microstrip Patch Antenna (RMPA) sensor technology

    SciTech Connect

    1996-06-27

    Theoretical research, controlled laboratory tests, and these field test results show that nonmetallic (and metallic) shallowly buried objects can be detected and imaged with the Resonant Microstrip Patch Antenna (RMPA) sensor. The sensor can be modeled as a high Q cavity which capitalizes on its resonant condition sensitivity to scattered waves from buried objects. When the RMPA sensor is swept over a shallowly buried object, the RMPA fed-point impedance (resistance), measured with a Maxwell bridge, changes by tens of percent. The significant change in unprocessed impedance data can be presented in two-dimensional and three-dimensional graphical displays over the survey area. This forms silhouette images of the objects without the application of computationally intensive data processing algorithms. Because RMPA employed electromagnetic waves to illuminate the shallowly buried object, a number of questions and issues arise in the decision to fund or deny funding of the reconfiguration of the RMPA technology into a nonmetallic (metallic) land mine detector.

  12. Cocamidopropyl betaine: the significance of positive patch test results in twelve patients.

    PubMed

    Fowler, J F

    1993-11-01

    Cocamidopropyl betaine is a surfactant coming into wide use in shampoos and other cleansing products. Recent reports have implicated it as a potential allergen, although it is less irritating than other surfactants such as sodium lauryl sulfate. Twelve positive patch test results were seen over a period of fifteen months of testing in selected patients. Of these, seven results were thought to be relevant. All seven patients with relevant reactions and four of the five with uncertain relevance had dermatitis of the head and neck area. It is concluded that although cocamidopropyl betaine is not a common allergen, it may be at least partially responsible for some cases of allergic dermatitis of the head and neck.

  13. Results of patch testing with a specialized collection of plastic and glue allergens.

    PubMed

    Holness, D L; Nethercottdagger, J R

    1997-06-01

    Patch testing was performed on 235 patients with a specialized collection of plastic and glue components. Thirteen percent had a positive response to at least one of the allergens. Seventy-four percent of the responses were relevant to either the present or a past problem, and 64% were occupationally related. The substances that yielded the greater percentage of positive responses were ethylenediamine, triethylenetetramine, diethylenetriamine, diaminodiphenylmethane, melamine formaldehyde resin, phenol formaldehyde resin, cresylglycidylether, phenylglycidylether, and N, N-dimethyl-p-toluidine. Of the 47 agents used, 26 did not elicit any positive responses. There were few distinguishing characteristics between those who exhibited a positive response to these agents and those who did not. In 12 cases (5% of those tested), the diagnosis of allergic contact dermatitis would have been missed if the plastics and glues components were not used.

  14. DKG statement on the use of metal alloy discs for patch testing in suspected intolerance to metal implants.

    PubMed

    Thomas, Peter; Geier, Johannes; Dickel, Heinrich; Diepgen, Thomas; Hillen, Uwe; Kreft, Burkhard; Schnuch, Axel; Szliska, Christiane; Mahler, Vera

    2015-10-01

    Intolerance reactions to metal implants may be caused by metal allergy. However, prior to implantation, 'prophetic'/prophylactic patch testing should not be performed. Pre-implant patch testing should only be done to verify or exclude metal allergy in patients with a corresponding history. In case of implant-related complications - in particular following replacement arthroplasty - such as pain, effusion, skin lesions, reduced range of motion or implant loosening, orthopedic causes should be ruled out first. Workup of suspected metal implant allergy should then be done using the DKG standard series, which includes nickel, cobalt, and chromium preparations. Various studies assessing the usefulness of metal alloy discs for patch testing have shown this particular approach to be ineffective with respect to providing reliable information on metal allergy. Any positive reaction in such tests cannot be assigned to a specific metal contained within the alloy. Furthermore, there is a risk of broad and indiscriminate use of these readily available discs. Accordingly, given the lack of additional benefit compared to patch testing with standardized metal salt preparations, we do not recommend patch testing with metal alloy discs.

  15. 365 Patch Testing Results in Contact Dermatitis from the Allergist's Perspective

    PubMed Central

    Aquino, Marcella; Michelis, Mary Ann; Lighvani, Sebastian; Davis-Lorton, Mark; Fonacier, Luz

    2012-01-01

    Background Contact Dermatitis (CD) is a frequently encountered skin disease by allergists and dermatologists that results from contact with external allergens. Patch Testing (PT) remains the gold standard in the diagnosis of allergic CD. Studies evaluating PT from allergy practices are lacking. Methods A multi-center, retrospective chart review of PT within the last 5 years at allergy practices in 3 institutions. We report PT results using allergens in the Thin-Layer Rapid-Use Epicutaneous Test (TT) and additional supplemental allergens [North American Contact Dermatitis (NACD) Panel, Dormer Cosmetic Panel, hairdresser's panel, corticosteroid panel and personal products]. Additionally, patient characteristics including age, gender, occupation, dermatitis site, history of atopic disease and final diagnosis were also obtained. Results A total of 427 patients (mean age = 49.8 years) were patch tested, 82% were female, 54% reported an atopic history (history of asthma, atopic dermatitis, allergic rhinitis or food allergy), 30% were tested with TT, 60% with NACD panel, 30% with cosmetic series, 15% with corticosteroid series and 35% with personal products. The 5 most common positive PT allergens were nickel sulfate, fragrance mix I, P-phenylenediamine, thimerosal and cobalt chloride. The most common dermatitis sites were eyelid/periorbital (31%), facial (25%) and trunk (21%). 56.9% of patients were positive to at least one TT allergen. 25.6% of patients were positive to both a TT and a supplemental allergen (these patients would have been “partially evaluated” with TT allergens alone as they are positive to at least 1 TT allergen and 1 supplemental allergen). 12.5% of patients were negative to a TT allergen and positive to at least 1 supplemental allergen only (these patients would have been “missed” as they are negative to all TT allergens, but positive to at least 1 supplemental allergen). Conclusions Nickel remains the most common allergen. When evaluating

  16. Immunoglobulin E-Mediated Allergy Plays a Role in Atopic Eczema as Shown in the Atopy Patch Test

    PubMed Central

    2008-01-01

    Although the pathophysiology of immunoglobulin E (IgE)-mediated allergic rhinoconjunctivitis and bronchial asthma is rather well established, the role of allergy in atopic eczema (AE) is still controversial. By a technique called atopy patch test, aeroallergens like house dust mite, animal dander, or pollen were proven as relevant trigger factors in a subgroup of patients with AE. The atopy patch test is an epicutaneous patch test with such allergens known to elicit IgE-mediated reactions, and used for the evaluation of eczematous skin reactions. In a series of single-center and multicenter studies, a method was developed, standardized, and compared with other diagnostic techniques (radioallergosorbent test, skin prick test) in AE patients. With regard to clinical history, the most specific results were obtained with the atopy patch test (allergen-dependent, 69%-92%), whereas sensitivity was higher for skin prick test (range, 69%-82%) and specific IgE (range, 65%-94%). The characterization of a patient subgroup with relevant IgE-mediated allergy may lead to more efficient avoidance and eventually even specific immunotherapy strategies in the management of AE. PMID:23283386

  17. Identification and testing of early indicators for N leaching from urine patches.

    PubMed

    Vogeler, Iris; Cichota, Rogerio; Snow, Val

    2013-11-30

    Nitrogen leaching from urine patches has been identified as a major source of nitrogen loss under intensive grazing dairy farming. Leaching is notoriously variable, influenced by management, soil type, year-to-year variation in climate and timing and rate of urine depositions. To identify early indicators for the risk of N leaching from urine patches for potential usage in a precision management system, we used the simulation model APSIM (Agricultural Production Systems SIMulator) to produce an extensive N leaching dataset for the Waikato region of New Zealand. In total, nearly forty thousand simulation runs with different combinations of soil type and urine deposition times, in 33 different years, were done. The risk forecasting indicators were chosen based on their practicality: being readily measured on farm (soil water content, temperature and pasture growth) or that could be centrally supplied to farms (such as actual and forecast weather data). The thresholds of the early indicators that are used to forecast a period for high risk of N leaching were determined via classification and regression tree analysis. The most informative factors were soil temperature, pasture dry matter production, and average soil water content in the top soil over the two weeks prior to the urine N application event. Rainfall and air temperature for the two weeks following urine deposition were also important to fine-tune the predictions. The identified early indicators were then tested for their potential to predict the risk of N leaching in two typical soils from the Waikato region in New Zealand. The accuracy of the predictions varied with the number of indicators, the soil type and the risk level, and the number of correct predictions ranged from about 45 to over 90%. Further expansion and fine-tuning of the indicators and the development of a practical N risk tool based on these indicators is needed.

  18. Winter season, frequent hand washing, and irritant patch test reactions to detergents are associated with hand dermatitis in healthcare workers

    PubMed Central

    Callahan, Adrienne; Baron, Elma; Fekedulegn, Desta; Kashon, Michael; Yucesoy, Berran; Johnson, Victor J.; Santo Domingo, Diana; Kirkland, Brent; Luster, Michael I.; Nedorost, Susan

    2013-01-01

    Background Irritant hand dermatitis (IHD) is common in healthcare workers. Objective We studied endogenous irritant contact dermatitis threshold by patch testing, and exogenous factors such as season and hand washing for their association with IHD in healthcare workers. Methods Irritant patch testing with sodium lauryl sulfate (SLS), sodium hydroxide (NaOH) and benzalkonium chloride (BAK) at varying concentrations was measured in 113 healthcare workers. Examination for hand dermatitis occurred at one month intervals for a period of six months in the Midwestern US. Results Positive patch testing to low concentration SLS was associated with IHD (p=0.0310) after adjusting for age, gender, ethnicity, season, history of childhood flexural dermatitis, mean indoor relative humidity, glove and hand sanitizer usage). Subjects with a positive patch test to SLS were 78% more likely to have occurrence of IHD (IRR=1.78, 95% CI: 0.92, 3.45). Hand washing frequency (≥ 10 times a day; IRR=1.55, 95% CI: 1.01, 2.39) and cold season (IRR=2.76, 95% CI: 1.35, 5.65) were associated with IHD. No association was found between history of childhood flexural dermatitis and IHD in this population. Conclusions Both genetic and environmental factors are important in the etiology of IHD and should be considered in designing strategies to protect, educate and treat susceptible individuals. PMID:23857011

  19. Allergy to tea tree oil: retrospective review of 41 cases with positive patch tests over 4.5 years.

    PubMed

    Rutherford, Tim; Nixon, Rosemary; Tam, Mei; Tate, Bruce

    2007-05-01

    Tea tree oil use is increasing, with considerable interest in it being a 'natural' antimicrobial. It is found in many commercially available skin and hair care products in Australia. We retrospectively reviewed our patch test data at the Skin and Cancer Foundation Victoria over a 4.5-year period and identified 41 cases of positive reactions to oxidized tea tree oil of 2320 people patch-tested, giving a prevalence of 1.8%. The tea tree oil reaction was deemed relevant to the presenting dermatitis in 17 of 41 (41%) patients. Of those with positive reactions, 27 of 41 (66%) recalled prior use of tea tree oil and eight of 41 (20%) specified prior application of neat (100%) tea tree oil. Tea tree oil allergic contact dermatitis is under-reported in the literature but is sufficiently common in Australia to warrant inclusion of tea tree oil, at a concentration of 10% in petrolatum, in standard patch-test series. Given tea tree oil from freshly opened tea tree oil products elicits no or weak reactions, oxidized tea tree oil should be used for patch testing.

  20. Patch testing and cross sensitivity study of adverse cutaneous drug reactions due to anticonvulsants: A preliminary report

    PubMed Central

    Shiny, T N; Mahajan, Vikram K; Mehta, Karaninder S; Chauhan, Pushpinder S; Rawat, Ritu; Sharma, Rajni

    2017-01-01

    AIM To evaluate the utility of patch test and cross-sensitivity patterns in patients with adverse cutaneous drug reactions (ACDR) from common anticonvulsants. METHODS Twenty-four (M:F = 13:11) patients aged 18-75 years with ACDR from anticonvulsants were patch tested 3-27 mo after complete recovery using carbamazepine, phenytoin, phenobarbitone, lamotrigine, and sodium valproate in 10%, 20% and 30% conc. in pet. after informed consent. Positive reactions persisting on D3 and D4 were considered significant. RESULTS Clinical patterns were exanthematous drug rash with or without systemic involvement (DRESS) in 18 (75%), Stevens-Johnsons syndrome/toxic epidermal necrolysis (SJS/TEN) overlap and TEN in 2 (8.3%) patients each, SJS and lichenoid drug eruption in 1 (4.2%) patient each, respectively. The implicated drugs were phenytoin in 14 (58.3%), carbamazepine in 9 (37.5%), phenobarbitone in 2 (8.3%), and lamotrigine in 1 (4.7%) patients, respectively. Twelve (50%) patients elicited positive reactions to implicated drugs; carbamazepine in 6 (50%), phenytoin alone in 4 (33.3%), phenobarbitone alone in 1 (8.3%), and both phenytoin and phenobarbitone in 1 (8.33%) patients, respectively. Cross-reactions occurred in 11 (92%) patients. Six patients with carbamazepine positive patch test reaction showed cross sensitivity with phenobarbitone, sodium valproate and/or lamotrigine. Three (75%) patients among positive phenytoin patch test reactions had cross reactions with phenobarbitone, lamotrigine, and/or valproate. CONCLUSION Carbamazepine remains the commonest anticonvulsant causing ACDRs and cross-reactions with other anticonvulsants are possible. Drug patch testing appears useful in DRESS for drug imputability and cross-reactions established clinically.

  1. Survey of Occupational Allergic Contact Dermatitis and Patch Test among Clothing Employees in Beijing

    PubMed Central

    Chen, Yu-Xin; Gao, Bing-Ai; Cheng, Hai-Yan

    2017-01-01

    Occupational population-based epidemiological data relating to occupational contact allergies in the Chinese clothing industry are limited. To investigate the prevalence of occupational allergic contact dermatitis (OACD) and to identify the causative allergens among clothing employees in China, a cross-sectional study was conducted in 529 clothing employees at 12 clothing factories in Beijing. All employees were subjected to an interview using self-administered questionnaire and skin examination, and those who were diagnosed with occupational contact dermatitis (OCD) were patch tested. In the present survey, we found that the overall 1-year prevalence of OACD among the clothing employees was 8.5%. The 1-year prevalence of OACD among workers (10.8%) was significantly higher than that among managers (3.2%). The lesions were primarily on the hands and wrists in workers, but the face and neck in managers. The major allergens were nickel sulfate and cobalt dichloride in workers and colophony and p-tert-butylphenol formaldehyde resin in managers. In conclusion, workers are at a higher risk of OACD compared with managers in the Chinese clothing industry. In addition to hand dermatitis in workers, airborne contact dermatitis on the face and neck should be also addressed in managers.

  2. Survey of Occupational Allergic Contact Dermatitis and Patch Test among Clothing Employees in Beijing.

    PubMed

    Chen, Yu-Xin; Gao, Bing-Ai; Cheng, Hai-Yan; Li, Lin-Feng

    2017-01-01

    Occupational population-based epidemiological data relating to occupational contact allergies in the Chinese clothing industry are limited. To investigate the prevalence of occupational allergic contact dermatitis (OACD) and to identify the causative allergens among clothing employees in China, a cross-sectional study was conducted in 529 clothing employees at 12 clothing factories in Beijing. All employees were subjected to an interview using self-administered questionnaire and skin examination, and those who were diagnosed with occupational contact dermatitis (OCD) were patch tested. In the present survey, we found that the overall 1-year prevalence of OACD among the clothing employees was 8.5%. The 1-year prevalence of OACD among workers (10.8%) was significantly higher than that among managers (3.2%). The lesions were primarily on the hands and wrists in workers, but the face and neck in managers. The major allergens were nickel sulfate and cobalt dichloride in workers and colophony and p-tert-butylphenol formaldehyde resin in managers. In conclusion, workers are at a higher risk of OACD compared with managers in the Chinese clothing industry. In addition to hand dermatitis in workers, airborne contact dermatitis on the face and neck should be also addressed in managers.

  3. Crude 4-methylcyclohexanemethanol (MCHM) did not cause skin irritation in humans in 48-h patch test.

    PubMed

    Monnot, Andrew D; Novick, Rachel M; Paustenbach, Dennis J

    2017-03-13

    Crude 4-methylcyclohexanemethanol (MCHM) is an industrial chemical used to wash and clean coal. On January 9th, 2014 approximately 10,000 gallons of a mixture containing crude MCHM were released into the Elk River near Charleston, West Virginia, contaminating the local water supply. Following the spill, residents reported numerous health complaints, and sought medical attention for ailments including rashes and itching. The relationship between the complaints and the spill were unknown, as such symptoms are reported frequently in the background. In this study, the primary irritation potential of crude MCHM was evaluated in 206 individuals who underwent 48 hour semi-occluded patch testing. MCHM concentrations assessed in this study were 1, 5, 15, and 100 ppm. No appreciable skin reactions were observed in individuals at any concentration. Three of the five concentrations evaluated were above the highest measured concentration of MCHM in the tap water of residents in West Virginia (3.7 ppm). The results of this study suggest that crude MCHM would not be a dermal irritant for the vast majority, if not all, potentially exposed persons at the concentrations in the water reported after the spill.

  4. Determination of acid base balance and oil water partition coefficient of an atopy patch test of levofloxacin.

    PubMed

    Lecordier, Julien; Lahet, Jean-Jacques; Courderot-Masuyer, Carol; Beaudoin, Etienne; Chaillot, Bernard

    2008-02-01

    Levofloxacin, a quinolone used in the treatment of an upper respiratory tract infection is involved in skin reactions. Patch tests are helpful for the aetiological diagnosis. Unfortunately, they are known for their lack of sensibility. A weak transcutaneous penetration due to the physicochemical characteristics of tested drugs is a well-known cause of false negative results but these characteristics are usually unknown. The aim of the present study was to evaluate physicochemical parameters by potentiometric method in order to optimize the transcutaneous penetration of a preparation for patch test. This method is applicable to a medium such as the preparation for patch test. In order to value the stability of the preparation, qualitative and quantitative analysis of the level of levofloxacin was effectuated. In our study, spectrophotometric and potentiometric data at T0 and six months later with the preparation showed the stability of the preparation. The proportions of non-ionized (45%) and ionized levofloxacin (55%) were not modified. Further experiments are needed to choose the minimal efficient dose of the suspected molecule able to detect a positive reaction in cases of allergic reaction. In addition, this method could be useful in qualitative and quantitative control of preparations made at hospital.

  5. Positive atopy patch test reaction to Malassezia furfur in atopic dermatitis correlates with a T helper 2-like peripheral blood mononuclear cells response.

    PubMed

    Johansson, Catharina; Eshaghi, Hojjat; Linder, Maria Tengvall; Jakobson, Eva; Scheynius, Annika

    2002-06-01

    The yeast Malassezia furfur belongs to the normal cutaneous flora, but is also a triggering allergen that can contribute to atopic dermatitis. To illuminate the effect of circulating allergen-specific T cells in atopic dermatitis, the peripheral mononuclear cell response was correlated with the in vivo skin prick test and atopy patch test reactivity to M. furfur. None of 16 healthy controls showed any positive in vivo reaction. The 40 atopic dermatitis patients, of whom 18 had serum IgE reactivity to M. furfur, were subdivided according to their in vivo reaction to M. furfur extract into three groups: skin prick test positive/atopy patch test positive (n = 12), skin prick test positive/atopy patch test negative (n = 12), and skin prick test negative/atopy patch test negative (n = 16). The skin prick test positive/atopy patch test positive and the skin prick test positive/atopy patch test negative groups had a significantly higher peripheral mononuclear cell stimulation index than the healthy controls. Interestingly, the stimulation index values in the skin prick test positive/atopy patch test positive group were significantly higher than in the skin prick test positive/atopy patch test negative group. In the M. furfur skin prick test positive atopic dermatitis patients (n = 24) a correlation was found between stimulation index and the M. furfur atopy patch test reactions, but not between stimulation index and M. furfur-specific serum IgE levels. Skin prick test positive and/or atopy patch test positive reactions to the recombinant M. furfur allergens rMal f 1, rMal f 5, and rMal f 6 were observed in 7, 14, and 16 of the 40 atopic dermatitis patients, respectively. Further, there was a correlation between production of the T helper 2-related cytokines interleukins 4, 5, and 13 and stimulation index to M. furfur extract, but not between the T helper 1-related interferon-gamma and stimulation index to M. furfur extract. Our data strongly suggest a relationship between

  6. Comparative assessment of the acute skin irritation potential of detergent formulations using a novel human 4-h patch test method.

    PubMed

    Robinson, Michael K; Kruszewski, Francis H; Al-Atrash, Jenan; Blazka, Mark E; Gingell, Ralph; Heitfeld, Fred A; Mallon, David; Snyder, Neil K; Swanson, Judith E; Casterton, Phillip L

    2005-12-01

    Predictive skin irritation test methods, which do not require use of animals, are needed for the pre-market assessment of detergent formulations. The utility of a novel and ethical human acute skin irritation patch test method, originally developed for chemical skin irritation assessment, was evaluated. In this IRB-approved method, subjects were patched under occlusion for increasing periods of time up to 4h in duration. The total incidence of positive skin reactions for test products was compared to a positive control (20% aqueous sodium dodecyl sulfate [SDS]). Acutely irritating formulas were defined as those showing a significantly increased or equal incidence of positive responders compared with that of SDS. The time of exposure required for 50% of subjects to show a positive skin reaction (TR50 value) was calculated for each product and enabled test product comparisons within and between studies. Using this approach, 24 detergent formulations of various types were tested in seven individual studies. The skin irritation profiles were generally consistent within product types, which could be categorized as follows (by decreasing irritancy): mold/mildew removers (average TR50 = 0.37 h) > disinfectants/sanitizers (0.64 h) > fabric softener concentrate (1.09 h) = aluminum wash (1.20 h) > 20% SDS (1.81 h) > liquid laundry detergents (3.48 h) > liquid dish detergents (4.16 h) = liquid fabric softeners (4.56 h) = liquid hand soaps (4.58 h) = shampoos (5.40 h) = hard surface cleaners (6.34 h) > powder automatic dish detergents (>16 h) = powder laundry detergents (>16 h). In addition to formulation effects, some seasonal effects were noted; particularly greater winter-time reactivity to 20% SDS and the hard surface cleaner and liquid laundry formulations. These results demonstrate the utility of this patch test method for the comparative skin irritation assessment of these different product types.

  7. Contact allergy to acid and neutral fractions of rosins. Sensitization experiments in guinea pigs and patch testing in patients.

    PubMed

    Karlberg, A T; Boman, A; Holmbom, B; Lidén, C

    1986-01-01

    The allergenicity of two different types of rosins (gum rosin and tall oil rosin) was compared. The rosins were divided into their neutral and acid fractions. The neutral fraction of tall oil rosin failed to induce contact sensitivity in animals tested according to the Guinea pig maximization test method (GPMT). The neutral fraction of gum rosin as well as the two acid fractions gave significant responses. Relatively fewer dermatitis patients reacted to the neutral fraction compared with reactions to the unfractionated gum rosin when patch tested. Fewer reactions to tall oil rosin than to gum rosin (p less than 0.05) were observed. It is concluded that tall oil rosin is less allergenic than gum rosin, which may be due to the absence of allergens in its neutral fraction.

  8. The Spanish standard patch test series: 2016 update by the Spanish Contact Dermatitis and Skin Allergy Research Group (GEIDAC).

    PubMed

    Hervella-Garcés, M; García-Gavín, J; Silvestre-Salvador, J F

    2016-09-01

    The Spanish standard patch test series, as recommended by the Spanish Contact Dermatitis and Skin Allergy Research Group (GEIDAC), has been updated for 2016. The new series replaces the 2012 version and contains the minimum set of allergens recommended for routine investigation of contact allergy in Spain from 2016 onwards. Four haptens -clioquinol, thimerosal, mercury, and primin- have been eliminated owing to a low frequency of relevant allergic reactions, while 3 new allergens -methylisothiazolinone, diazolidinyl urea, and imidazolidinyl urea- have been added. GEIDAC has also modified the recommended aqueous solution concentrations for the 2 classic, major haptens methylchloroisothiazolinone and methylisothiazolinone, which are now to be tested at 200ppm in aqueous solution, and formaldehyde, which is now to be tested in a 2% aqueous solution. Updating the Spanish standard series is one of the functions of GEIDAC, which is responsible for ensuring that the standard series is suited to the country's epidemiological profile and pattern of contact sensitization.

  9. Skin irritation to glass wool or continuous glass filaments as observed by a patch test among human Japanese volunteers.

    PubMed

    Tsunoda, Masashi; Kido, Takamasa; Mogi, Sachiyo; Sugiura, Yumiko; Miyajima, Eriko; Kudo, Yuichiro; Kumazawa, Tatenao; Aizawa, Yoshiharu

    2014-01-01

    Glass wool and continuous glass filaments have been used in industry. We examined the irritability of those among Japanese. A patch test was performed on 43 volunteers for the followings: glass wool for non-residential use with and without a urea-modified phenolic resin binder, that for residential use with and without the binder, and continuous glass filaments with diameters of 4, 7, 9, and 13 µm. Materials were applied to an upper arm of each volunteer for 24 h. The skin was observed at 1 and 24 h after the removal. At 1 h after removal, slight erythema was observed on the skin of a woman after the exposure to glass wool for residential use without the binder. Erythema was observed on the skin of another woman at 1 h after a 24-h exposure to glass wool for non-residential use without the binder. There were no reactions at 24 h after the removal. The low reactions in the patch test suggested that the irritability caused by glass wool, irrespective of a resin component, could be induced mechanically, and that the irritability caused by continuous glass filaments with resin could be slight and either mechanical or chemical.

  10. Distributions-per-level: a means of testing level detectors and models of patch-clamp data.

    PubMed

    Schröder, I; Huth, T; Suitchmezian, V; Jarosik, J; Schnell, S; Hansen, U P

    2004-01-01

    Level or jump detectors generate the reconstructed time series from a noisy record of patch-clamp current. The reconstructed time series is used to create dwell-time histograms for the kinetic analysis of the Markov model of the investigated ion channel. It is shown here that some additional lines in the software of such a detector can provide a powerful new means of patch-clamp analysis. For each current level that can be recognized by the detector, an array is declared. The new software assigns every data point of the original time series to the array that belongs to the actual state of the detector. From the data sets in these arrays distributions-per-level are generated. Simulated and experimental time series analyzed by Hinkley detectors are used to demonstrate the benefits of these distributions-per-level. First, they can serve as a test of the reliability of jump and level detectors. Second, they can reveal beta distributions as resulting from fast gating that would usually be hidden in the overall amplitude histogram. Probably the most valuable feature is that the malfunctions of the Hinkley detectors turn out to depend on the Markov model of the ion channel. Thus, the errors revealed by the distributions-per-level can be used to distinguish between different putative Markov models of the measured time series.

  11. Atopy patch tests in young adult patients with atopic dermatitis and controls: dose-response relationship, objective reading, reproducibility and clinical interpretation.

    PubMed

    Bygum, Anette; Mortz, Charlotte Gotthard; Andersen, Klaus Ejner

    2003-01-01

    The clinical interpretation and reproducibility of atopy patch tests was studied in 23 selected young adult patients with atopic dermatitis and 25 healthy controls using standard inhalant allergens. Non-invasive measurements were used for objective assessment of test reactions and the participants were retested after 6 weeks. Ten of 19 (53%) evaluable patients with atopic dermatitis had at least one positive atopy patch test. However, there was no clear clinical relevance of the atopy patch test results when related to patient history and distribution of dermatitis. Reproducible and dose-dependent results were obtained with Dermatophagoides pteronyssinus, grass and cat with a reproducibility rate of 0.69 to 0.81 in patients and 0.60-0.96 in controls. A unique finding was a significant positive correlation between a positive atopy patch test, allergen dose and increase in transepidermal water loss and erythema, while measurement of capacitance did not distinguish between positive and negative reactions. The results of the present study do not support the routine use of atopy patch tests in the evaluation of adult patients with atopic dermatitis.

  12. Results of tests of K5NA and a revised formulation of EPDM/cork patch material in MSFC Hot Gas Facility

    NASA Technical Reports Server (NTRS)

    Dean, W. G.

    1982-01-01

    During prelaunch procedures at Kennedy Space Center some of the EPDM Thermal Protection System material was damaged on the Solid Rocket Booster stiffener stubs. The preferred solution was to patch the damaged areas with a cork-filled epoxy patching compound. Before this was done, however, it was requested that this patching technique be checked out by testing it in the MSFC Hot Gas Facility. Two tests were run in the HFG in 1980. The results showed the patch material to be adequate. Since that time, the formulation of the cork-filled epoxy material has been changed. It became necessary to retest this concept to be sure that the new material is as good as or better than the original material. In addition to the revised formulation material, tests were also made using K5NA as the patch material. The objectives of the tests reported herein were to: (1) compare the thermal performance of the original and the new cork-filled epoxy formulations, and (2) compare the K5NA closeout material to these epoxy materials. Material specifications are also discussed.

  13. An experimental test of the effects of food resources and hydraulic refuge on patch colonization by stream macroinvertebrates during spates.

    PubMed

    Negishi, Junjiro N; Richardson, John S

    2006-01-01

    1. The passive or active movement of organisms between habitat patches plays important roles in achieving ecosystem resilience to disturbance and long-term control of population levels. However, causal mechanisms of disturbance-induced movements of mobile biota across heterogeneous habitat patches at a relatively short time-scale are little understood. 2. We experimentally tested the effects of food resource values on macroinvertebrate colonization of hydraulic refugia from spates in a second-order creek. Experimental cages were colonized by macroinvertebrates with combinations of resource types (natural or polyester leaves), and extent of exposure to stream flow (exposed to or sheltered from current); one half of each set was collected before and after a spate. This experiment was repeated over three spates of varying magnitude and seasonal contexts. 3. Pre-spate colonization was consistently greater for the cages with natural leaves relative to artificial leaves regardless of the extent of flow exposure. Two autumn spates with relatively low and stable antecedent flow conditions caused large movements of organic matter and macroinvertebrates across the stream, showing community-level accumulations into hydraulically sheltered patches independent of food treatment. The smallest spate with high and variable antecedent flows during winter resulted in negligible responses, which we interpret to be a result of depletion of easily transportable organic matter and organisms. 4. Two detritivorous taxa, the mayfly Paraleptophlebia spp. and stonefly Despaxia augusta (Banks) were the most responsive to autumn spates, and had disproportionately higher colonization rates of cages when provided with natural leaves during the largest autumn spate. Preferential settlement in food-enriched hydraulic refugia was attributable to taxon-specific mobility related to efficient acquisition of detritus resource, whose availability varies spatially and temporally. 5. Our findings suggest

  14. Phototoxicity of bergamot oil assessed by in vitro techniques in combination with human patch tests.

    PubMed

    Kejlová, K; Jírová, D; Bendová, H; Kandárová, H; Weidenhoffer, Z; Kolárová, H; Liebsch, M

    2007-10-01

    The aim of this study was to clarify the differences in the phototoxicity of bergamot oil obtained from four different suppliers. Spectral and chemical analyses were performed to identify presence of photoactive compounds in the test samples. The phototoxicity was assessed in vitro by the 3T3 NRU phototoxicity test (PT) and subsequently in a phototoxicity test on reconstructed human skin model (H3D PT). Confirmatory photopatch tests in a group of volunteers were performed using the first non-phototoxic concentration determined in the H3D PT. The spectral and chemical analyses revealed, that two samples of bergamot oil exhibited a potential for photoactivation. These oils were subsequently classified as phototoxic in the 3T3 NRU PT, however, only on the basis of borderline results and depending on the solvent used. H3D PT revealed clear classifications, correlating well with the findings of spectral and chemical analysis. The test was, however, not yet capable of precise prediction of safe, non-phototoxic concentrations. Additional endpoints, e.g. interleukin determination might be employed to increase the sensitivity of the test. Although the study showed the usefulness of the tiered testing strategy, currently, the extrapolation of in vitro results to human situation may be performed only to a limited extent.

  15. Effects of different base agents on prediction of skin irritation by sodium lauryl sulfate using patch testing and repeated application test.

    PubMed

    Horita, Kotomi; Horita, Daisuke; Tomita, Hiroyuki; Yasoshima, Mitsue; Yagami, Akiko; Matsunaga, Kayoko

    2017-03-06

    Animal testing for cosmetics was banned in the European Union (EU) in 2013; therefore, human tests to predict and ensure skin safety such as the patch test or usage test are now in demand in Japan as well as in the EU. In order to investigate the effects of different bases on the findings of tests to predict skin irritation, we performed patch testing (PT) and the repeated application test (RAT) using sodium lauryl sulfate (SLS), a well-known irritant, dissolved in 6 different base agents to examine the effects of these bases on skin irritation by SLS. The bases for PT were distilled water, 50% ethanol, 100% ethanol, a gel containing 50% ethanol, white petrolatum, and hydrophilic cream. The concentrations of SLS were 0.2% and 0.5%. Twelve different base combinations were applied to the normal back skin of 19 individuals for 24h. RAT was performed with distilled water, 50% ethanol, 100% ethanol, a gel containing 50% ethanol, white petrolatum, and hydrophilic cream containing SLS at concentrations of 0.2%, 2%, and 5%, being applied to the arms of the same PT subjects. The test preparation of each base was applied at the same site, with 0.2% SLS being used in the first week, 2% SLS in the following week, and 5% SLS in the final week. The results of PT revealed that skin irritation scores varied when SLS at the same concentration was dissolved in a different base. The results of RAT showed that although skin irritation appeared with every base at a concentration of 5%, the positive rate was approximately the same. In conclusion, our results suggest that skin irritation elicited in PT depends on the base, while in RAT, it does not depend on the type of base employed.

  16. Use of the cytosensor microphysiometer to predict results of a 21-day cumulative irritation patch test in humans.

    PubMed

    Landin, Wendell E; Mun, Greg C; Nims, Raymond W; Harbell, John W

    2007-09-01

    The cytosensor microphysiometer (mu phi) was investigated as a rapid, relatively inexpensive test to predict performance of skin cleansing wipes on the human 21-day cumulative irritation patch test (21CIPT). It indirectly measures metabolic rate changes in L929 cells as a function of test article dose, by measuring the acidification rate in a low-buffer medium. The dose producing a 50% reduction in metabolic rate (MRD50), relative to the baseline rate, is used as a measure of toxicity. The acute toxicity of the mu phi assay can be compared to the chronic toxicity of the 21CIPT, which is based largely on the exposure of test agents to the epidermal cells, resulting in damage and penetration of the stratum corneum leading to cell toxicity. Two series of surfactant-based cleansing wipe products were tested via the mu phi assay and 21CIPT. The first series, consisting of 20 products, was used to determine a prediction model. The second series of 38 products consisted of routine product development formulas or marketed products. Comparing the results from both tests, samples with an MRD50 greater than 50 mg/ml provided a 21CIPT score consistent with a product that performs satisfactorily in the market. When the MRD50 was greater than 78 mg/ml, the 21CIPT score was usually zero. The mu phi may be more sensitive than the 21CIPT for ranking minimally irritating materials. The mu phi assay is useful as a screen for predicting the performance of a wet wipes formula on the 21CIPT, and concurrently reduces the use of animals for safety testing in a product development program for cleansing wipes.

  17. Patch test results in children and adolescents. Study from the Santa Casa de Belo Horizonte Dermatology Clinic, Brazil, from 2003 to 2010*

    PubMed Central

    Rodrigues, Dulcilea Ferraz; Goulart, Eugênio Marcos Andrade

    2015-01-01

    BACKGROUND Patch testing is an efficient method to identify the allergen responsible for allergic contact dermatitis. OBJECTIVE To evaluate the results of patch tests in children and adolescents comparing these two age groups' results. METHODS Cross-sectional study to assess patch test results of 125 children and adolescents aged 1-19 years, with suspected allergic contact dermatitis, in a dermatology clinic in Brazil. Two Brazilian standardized series were used. RESULTS Seventy four (59.2%) patients had "at least one positive reaction" to the patch test. Among these positive tests, 77.0% were deemed relevant. The most frequent allergens were nickel (36.8%), thimerosal (18.4%), tosylamide formaldehyde resin (6.8%), neomycin (6.4%), cobalt (4.0%) and fragrance mix I (4.0%). The most frequent positive tests came from adolescents (p=0.0014) and females (p=0.0002). There was no relevant statistical difference concerning contact sensitizations among patients with or without atopic history. However, there were significant differences regarding sensitization to nickel (p=0.029) and thimerosal (p=0.042) between the two age groups under study, while adolescents were the most affected. CONCLUSION Nickel and fragrances were the only positive (and relevant) allergens in children. Nickel and tosylamide formaldehyde resin were the most frequent and relevant allergens among adolescents. PMID:26560213

  18. Multicentre patch testing with compositae mix by the Swedish Contact Dermatitis Research Group.

    PubMed

    Isaksson, Marléne; Hansson, Christer; Inerot, Annica; Lidén, Carola; Matura, Mihaly; Stenberg, Berndt; Möller, Halvor; Bruze, Magnus

    2011-05-01

    Sesquiterpene lactone mix detects contact allergy to these compounds present in the plant family Asteraceae. This marker is present in many baseline series. An additional marker is Compositae mix, which is not present in many baseline series. To investigate whether this allergen should be inserted into the Swedish baseline series, six dermatology centres representing the Swedish Contact Dermatitis Research Group included Compositae mix into their baseline series for 1.5 years. Of 2818 patients tested, 31 (1.1%) reacted to Compositae mix and 26 (0.9%) to Sesquiterpene lactone mix. Active sensitization to Compositae mix was noted in two cases. Only 0.4% of Asteraceae contact allergy cases would have been missed if Compositae mix had not been tested, a frequency too low to merit its inclusion in the baseline series. Due to obvious geographical differences in frequency in frequency of simultaneous allergic reactions to Compositae mix and Sesquiterpene lactone mix, the question as to whether specific baseline series (including Compositae mix or not as a "tail" substance) should be used in the different centres must be addressed. Another option could be to remove Sesquiterpene lactone mix from the baseline series and substitute it with Compositae mix.

  19. Application of Near-Field Microwave and Millimeter Wave Nondestructive Testing for Evaluation of Fiber Breakage and Orientation Evaluation in CFRP Composite Patches

    NASA Astrophysics Data System (ADS)

    Kharkovsky, S.; Zoughi, R.

    2005-04-01

    Near-field microwave and millimeter wave nondestructive testing and evaluation techniques have been successfully used for detecting defects such as disbond and delamination in complex composite structures. This paper presents the results of fiber breakage detection and fiber orientation determination in carbon fiber reinforced polymer patches which are used in aerospace industry and civil infrastructure.

  20. Allergic contact stomatitis to dodecyl gallate? A review of the relevance of positive patch test results to gallates.

    PubMed

    Gamboni, Sarah E; Palmer, Amanda M; Nixon, Rosemary L

    2013-08-01

    Gallic acid esters or gallates are antioxidants used as preservatives in food and cosmetics. Few cases of gallates causing allergic contact dermatitis (ACD) have been reported in the literature. We present a case report of a 42-year-old beauty therapist who presented with a swollen tongue. Patch testing was positive to dodecyl gallate, commonly reported as being present in edible oil and oily foods such as margarine. Our patient avoided foods presumed to contain gallates and at the 6-week review reported a substantial improvement in her tongue symptoms. We reviewed our database and found 16 (7%) definitely or possibly relevant reactions to dodecyl gallate, seven (15%) definitely or possibly relevant reactions to propyl gallate and six (3%) definitely or possibly relevant reactions to octyl gallate. Most reactions were attributed to margarine, moisturising cream and lipstick. These products are often mentioned in the literature as containing gallates; however, ingredient labelling and discussions with manufacturers made it difficult to establish whether they are currently present in foods. Ascertaining relevance for these reactions is not always possible.

  1. Patch test reactions to mite antigens: a GERDA multicentre study. Groupe d'Etudes et de Recherches en Dermato-Allergie.

    PubMed

    Castelain, M; Birnbaum, J; Castelain, P Y; Ducombs, G; Grosshans, E; Jelen, G; Lacroix, M; Meynadier, J; Mougeolle, J M; Lachapelle, J M

    1993-11-01

    We performed patch tests with Dermatophagoides pteronyssinus (Dp) antigens from 2 different sources in 355 non-randomly selected patients with atopic dermatitis (AD) and 398 subjects of a control group. The study demonstrated that contact sensitization to mites occurred in an appreciable % of AD cases (20.8%), using commonly available assay products. The differences recorded between the 2 materials tested were related to the concentration of P1 antigen. Non-atopic patients rarely showed positive reactions to Dp (0.75%), when strict criteria for readings were applied and if 2 readings were performed. Patients with positive patch tests did not necessarily show positive immediate skin tests. It would be useful to carry out tests systematically in atopic patients, even if it is not yet known what modern treatment would be best for the patient. Laboratories still do not provide standardized house dust mite preparations--measuring and codifying their biological activity--for use in patch tests. It is to be hoped that the extension of this type of test will lead to the production of better test materials, in syringes with homogeneous dispersion and concentration.

  2. In vitro testing of tensides employing monolayer cultures: a comparison with results of patch tests on human volunteers.

    PubMed

    Benassi, L; Bertazzoni, G; Seidenari, S

    1999-01-01

    Evaluation of the irritant potential of new products or ingredients prior to human testing is generally performed in vivo on animals. However, according to the 6th amendment and following updates of the European Community directive on cosmetic products (93/35/EEC), animal testing will be banned when suitable substitutes will be available. To know whether in vitro tests for assessment of skin irritancy provide results approaching human conditions, comparisons have to be made between data deriving from in vitro tests and skin response in humans. The aim of our study was to assess the validity of the monolayer culture system of normal human keratinocytes as a model for the evaluation of the irritant effects of detergents, by comparing in vitro cell culture data to in vivo acute skin irritancy effects of cocamidopropyl betaine (CAPB), an amphoteric compound, Tween 20 (TW20) (polysorbate 20) and Tween 80 (TW80) (polysorbate 80), representing nonionic compounds, applied to the skin of 24 healthy volunteers at a concentration similar to that employed in commercial products. As parameters for cytotoxicity, cell proliferation, cell membrane integrity and cell metabolism were assessed by cell counts, thymidine incorporation, MTT conversion, and Neutral Red uptake. In order to increase the sensitivity of the in vivo evaluation, bioengineering methods for assessment of the effects of test products on the skin were employed. Whereas all 4 in vitro methods ranked the tensides according to their toxicity in the following order: CAPB>SLS>TW20>TW80, both in vivo methods agreed in identifying SLS as the most irritating substance. Moreover, as compared with the irritation potential on human skin, all 4 in vitro tests overestimated the toxicity of CAPB. This suggests that the keratinocyte monolayer cell culture technique cannot directly replace in vivo methods, and that data obtained by this method should be interpreted cautiously.

  3. A case of acute generalized exanthematous pustulosis due to amoxicillin-clavulanate with multiple positivity to beta-lactam patch testing.

    PubMed

    Bomarrito, L; Zisa, G; Delrosso, G; Farinelli, P; Galimberti, M

    2013-09-01

    We present a case of acute generalized exanthematous pustolosis (AGEP) induced by amoxicillin-clavulanate. Clinical diagnosis was confirmed by symptoms presentation and  histological features (Euroscar score point compatible with definite diagnosis). Patch testing performer six months later confirmed sensitization to the culprit drug and showed positivity also to other beta-lactam antibiotics (penicillin G and cephalexin). We believe that a T cell delayed response to betalactams common ring could be involved.

  4. Granisetron Transdermal Patch

    MedlinePlus

    ... patch. Each patch is stuck onto a thin plastic liner and a separate rigid plastic film. Do not open the pouch in advance, ... cut the patch into pieces. Peel the thin plastic liner off of the printed side of the ...

  5. Spin Glass Patch Planting

    NASA Technical Reports Server (NTRS)

    Wang, Wenlong; Mandra, Salvatore; Katzgraber, Helmut G.

    2016-01-01

    In this paper, we propose a patch planting method for creating arbitrarily large spin glass instances with known ground states. The scaling of the computational complexity of these instances with various block numbers and sizes is investigated and compared with random instances using population annealing Monte Carlo and the quantum annealing DW2X machine. The method can be useful for benchmarking tests for future generation quantum annealing machines, classical and quantum mechanical optimization algorithms.

  6. Cabbage Patch

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This Sojourner rover image of the Cabbage Patch shows small rounded objects on the surface that are about 3-4 cm across. Some of these are within excavations, which are about 0.5 cm wide. Several questions arise about the pebbles: Why are they rounded? Where did they come from? What do they mean?

    Geologists use MULTIPLE WORKING HYPOTHESES when attempting to explain observations. Some hypotheses that could account for the pebbles are: They were rounded during transport by waters of catastrophic floods and deposited on the Ares Vallis floodplain They were rounded by wave action on an ancient Martian beach They were rounded during glacial transport They are glasses that were produced by melting during impact cratering. The glass was first ejected from the crater, then molded into spherical shapes or drops as it traveled through the atmosphere, and finally was deposited at the sites They are spatter from lava flows They are nodules brought up from the deep Martian interior by lava flows or pyroclastic eruptions. They are concretions formed in sedimentary rocks They came from ancient conglomerate rocks. The pebbles were rounded by water action and subsequently lithified into conglomerate rocks. Later, the waters of catastrophic floods transported the conglomerates and deposited them on the Ares floodplain. The pebbles were then freed from the rocks by weathering. A combination of the above

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  7. Release of nickel ions from stainless steel alloys used in dental braces and their patch test reactivity in nickel-sensitive individuals.

    PubMed

    Jensen, Christian Stab; Lisby, Steen; Baadsgaard, Ole; Byrialsen, Kirsten; Menné, Torkil

    2003-06-01

    Nickel ions leached in sufficient quantities from nickel-containing alloys may induce nickel sensitization or elicit allergic contact dermatitis. Nickel-containing stainless steel alloys are generally considered safe for nickel-sensitive individuals to use. The study summarized in this paper investigated 3 parameters. First, the release of nickel was estimated in artificial saliva and sweat from 4 different stainless steel alloys frequently used in dental braces. Second, in a pilot study, oral mucosa cells harvested from 3 dental patients before and after the attachment of dental braces were analysed for possible nickel content. Third, patch test reactivity of the 4 stainless steel alloys was tested on 31 nickel-sensitive subjects. All 4 stainless steel alloys released small amounts of nickel ions into artificial saliva (<0.13 micro g/cm2/week) and artificial sweat (<0.05 micro g/cm2/week), but no measurable amounts of nickel were found in any of the oral mucosa samples. None of the 31 nickel-sensitive subjects reacted to patch testing with the 4 stainless steel alloys, indicating that these stainless steel alloys would be safe to use in direct and prolonged contact with the skin.

  8. Patching. Restitching business portfolios in dynamic markets.

    PubMed

    Eisenhardt, K M; Brown, S L

    1999-01-01

    In turbulent markets, businesses and opportunities are constantly falling out of alignment. New technologies and emerging markets create fresh opportunities. Converging markets produce more. And of course, some markets fade. In this landscape of continuous flux, it's more important to build corporate-level strategic processes that enable dynamic repositioning than it is to build any particular defensible position. That's why smart corporate strategists use patching, a process of mapping and remapping business units to create a shifting mix of highly focused, tightly aligned businesses that can respond to changing market opportunities. Patching is not just another name for reorganizing; patchers have a distinctive mindset. Traditional managers see structure as stable; patching managers believe structure is inherently temporary. Traditional managers set corporate strategy first, but patching managers keep the organization focused on the right set of business opportunities and let strategy emerge from individual businesses. Although the focus of patching is flexibility, the process itself follows a pattern. Patching changes are usually small in scale and made frequently. Patching should be done quickly; the emphasis is on getting the patch about right and fixing problems later. Patches should have a test drive before they're formalized but then be tightly scripted after they've been announced. And patching won't work without the right infrastructure: modular business units, fine-grained and complete unit-level metrics, and companywide compensation parity. The authors illustrate how patching works and point out some common stumbling blocks.

  9. Scopolamine Transdermal Patch

    MedlinePlus

    ... patch from its protective pouch. To expose the adhesive surface of the patch, the clear plastic protective ... peeled off and discarded. Contact with the exposed adhesive layer should be avoided to prevent contamination of ...

  10. SafePatch

    SciTech Connect

    Kelley, M.; Elko, S.

    2000-10-01

    Authenticating and upgrading system software plays a critical role in information security, yet practical tools for assessing and installing software are lacking in today's marketplace. The SafePatch tool provides the mechanism of performing automated analysis, notification, distribution, and installation of security patches and related software to network-based computer systems in a vendor-independent fashion. SafePatch assists in the authentication of software by comparing the system's objects with the patch's objects. SafePatch will monitor vendor's sites to determine when new patches are released and will upgrade system software on target systems automatically. This paper describes the design of SafePatch, motivations behind the project and the advantages of SafePatch over existing tools.

  11. Metal Patch Antenna

    NASA Technical Reports Server (NTRS)

    Chamberlain, Neil F. (Inventor); Hodges, Richard E. (Inventor); Zawadzki, Mark S. (Inventor)

    2012-01-01

    Disclosed herein is a patch antenna comprises a planar conductive patch attached to a ground plane by a support member, and a probe connector in electrical communication with the conductive patch arranged to conduct electromagnetic energy to or from the conductive patch, wherein the conductive patch is disposed essentially parallel to the ground plane and is separated from the ground plane by a spacing distance; wherein the support member comprises a plurality of sides disposed about a central axis oriented perpendicular to the conductive patch and the ground plane; wherein the conductive patch is solely supported above the ground plane by the support member; and wherein the support member provides electrical communication between the planer conductive patch and the ground plane.

  12. Birth Control Patch

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Birth Control Patch KidsHealth > For Teens > Birth Control Patch A A A What's in this article? ... Much Does It Cost? What Is It? The birth control patch is a thin, beige, 1¾-inch (4½- ...

  13. Birth Control Patch

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Birth Control Patch KidsHealth > For Teens > Birth Control Patch Print A A A What's in this ... Much Does It Cost? What Is It? The birth control patch is a thin, beige, 1¾-inch (4½- ...

  14. Positive patch- and photopatch-test reactions to methylene bis-benzotriazolyl tetramethylbutylphenol in patients with both atopic dermatitis and chronic actinic dermatitis.

    PubMed

    Gonzalez, Mercedes E; Soter, Nicholas A; Cohen, David E

    2011-01-01

    Ultraviolet filters are the most common topical photoallergens. Although currently not available on the US market, methylene bis-benzotriazolyl tetramethylbutylphenol (referred to as bisoctrizole on product labels) represents a new class of UV filters that have both organic and inorganic properties and are widely available in different preparations in Europe, South America, and Asia. We report two patients with atopic dermatitis and chronic actinic dermatitis who had positive patch- and photopatch-test reactions, which suggested both an allergic contact and a photoallergic contact dermatitis from bisoctrizole. Neither patient could identify previous or current contact with the chemical; nonetheless, it is possible that either the allergic contact or photoallergic contact dermatitis from bisoctrizole led to their chronic actinic dermatitis.

  15. Dispersal, patch leaving, and distribution of Homalodisca vitripennis (Hemiptera: Cicadellidae).

    PubMed

    Northfield, Tobin D; Mizell, Russell F; Paini, Dean R; Andersen, Peter C; Brodbeck, Brent V; Riddle, T Charles; Hunter, Wayne B

    2009-02-01

    Homalodisca vitripennis (Germar) and related species have caused millions of dollars in damage to southern California vineyards in recent years through the vectoring of Pierce's disease. However, the effects of surrounding vegetation on the dispersal and distribution of H. vitripennis are poorly understood. Therefore, the relationship between dispersal rates and patch quality was tested, as well as the basic predictions of the marginal value theorem. Additional experiments were conducted to compare the H. vitripennis distribution in an isolated crape myrtle (Lagerstroemia indica) patch and a L. indica patch bordering two alternative host patches. In mark-release-recapture tests, H. vitripennis dispersed farther from the release point in a patch of low-quality host plants (Prunus persica) than in patches of high-quality host plants (L. indica). In addition, H. vitripennis remained in L. indica patches longer than in P. persica patches and adjusted patch residence times in P. persica in correlation with known changes in plant physiology. These data suggest that H. vitripennis follows the basic predictions of marginal value theorem. In distribution tests, H. vitripennis were more abundant in the patch center than patch edges in the isolated L. indica patch, but in a patch bordering cottonwood (Populus sp.) and peach (P. persica), H. vitripennis numbers were generally higher along the edges of the patch. These data suggest that alternate hosts bordering cropping systems may be important to the spatial dynamics of H. vitripennis. Implications of these spatial observations on the biology of H. vitripennis and potential control methods are discussed.

  16. Corridor Length and Patch Colonization by a Butterfly Junonia coenia

    SciTech Connect

    Nick Haddad

    2000-06-01

    Habitat corridors have been proposed to reduce patch isolation and increase population persistence in fragmented landscapes. This study tested whether patch colonization was increased by the presence and various length corridors. The specific butterfly species tested has been shown to use corridors, however, the results indicate that neither the distance between patches or the presence of a corridor influenced colonization.

  17. Noninvasive measuring methods for the investigation of irritant patch test reactions. A study of patients with hand eczema, atopic dermatitis and controls.

    PubMed

    Agner, T

    1992-01-01

    The aim of the study was to assess the susceptibility of clinically normal skin to a standard irritant trauma under varying physiological and patophysiological conditions. Evaluation of skin responses to patch tests with sodium lauryl sulphate (SLS) was used for assessment of skin susceptibility. The following noninvasive measuring methods were used for evaluation of the skin before and after exposure to irritants: measurement of transepidermal water loss by an evaporimeter, measurement of electrical conductance by a hydrometer, measurement of skin blood flow by laser Doppler flowmetry, measurement of skin colour by a colorimeter and measurement of skin thickness by ultrasound A-scan. The studies were carried out on healthy volunteers and patients with eczema. In the first studies the standard irritant patch test for assessment of skin susceptibility was characterized and validated. SLS was chosen among other irritants because of its ability to penetrate and impair the skin barrier. The implications of use of different qualities of SLS was investigated. The applied noninvasive measuring methods were evaluated, and for quantification of SLS-induced skin damage measurement of TEWL was found to be the most sensitive method. Application of the standard test on clinically normal skin under varying physiological and patophysiological conditions lead to the following main results: Seasonal variation in skin susceptibility to SLS was found, with increased susceptibility in winter, when the hydration state of the stratum corneum was also found to be decreased. A variation in skin reactivity to SLS during the menstrual cycle was demonstrated, with an increased skin response at day 1 as compared to days 9-11 in the menstrual cycle. The presence of active eczema distant from the test site increased skin susceptibility to SLS, indicating a generalized hyperreactivity of the skin. Taking these sources of variation into account healthy volunteers and patients with hand eczema and

  18. Nickel-Related Intestinal Mucositis in IBS-Like Patients: Laser Doppler Perfusion Imaging and Oral Mucosa Patch Test in Use.

    PubMed

    Borghini, Raffaele; Puzzono, Marta; Rosato, Edoardo; Di Tola, Marco; Marino, Mariacatia; Greco, Francesca; Picarelli, Antonio

    2016-09-01

    Nickel (Ni) is often the trigger of irritable bowel syndrome (IBS)-like gastrointestinal disorders: its ingestion may cause allergic contact mucositis, identifiable by means of oral mucosa patch test (omPT). OmPT effectiveness has been proven, but it is still an operator-dependent method. Laser Doppler perfusion imaging (LDPI) was tested to support omPT in Ni allergic contact mucositis diagnosis. Group A: 22 patients with intestinal/systemic symptoms related to the ingestion of Ni-containing foods. Group B: 12 asymptomatic volunteers. Ni-related symptoms and their severity were tested by a questionnaire. All patients underwent Ni omPT with clinical evaluation at baseline (T0), after 30 min (T1), after 2 h (T2), and after 24-48 h (T3). LDPI was performed to evaluate the mean mucosal perfusion at T0, T1, and T2. Statistical analysis was performed by ANOVA test and Bonferroni multiple-comparison test. All 22 Ni-sensitive patients (group A) presented oral mucosa hyperemia and/or edema at T2. Eight out of the same 22 patients presented a local delayed vesicular reaction at T3 (group A1), unlike the remaining 14 out of 22 patients (group A2). All 12 patients belonging to control group B did not show any alteration. The mean mucosal perfusion calculated with LDPI showed an increase in both subgroups A1 and A2. In group B, no significant perfusion variations were observed. LDPI may support omPT for diagnostic purposes in Ni allergic contact mucositis. This also applies to symptomatic Ni-sensitive patients without aphthous stomatitis after 24-48 h from omPT and that could risk to miss the diagnosis.

  19. Frequent occurrence of T cell–mediated late reactions revealed by atopy patch testing with hypoallergenic rBet v 1 fragments

    PubMed Central

    Campana, Raffaela; Moritz, Katharina; Marth, Katharina; Neubauer, Angela; Huber, Hans; Henning, Rainer; Blatt, Katharina; Hoermann, Gregor; Brodie, Tess M.; Kaider, Alexandra; Valent, Peter; Sallusto, Federica; Wöhrl, Stefan; Valenta, Rudolf

    2015-01-01

    Background Late allergic reactions are common in the course of allergen-specific immunotherapy and even occur with allergy vaccines with reduced IgE reactivity. Objective We sought to study atopy patch test (APT) reactions and T-cell responses to the recombinant birch pollen allergen Bet v 1 and recombinant hypoallergenic T-cell epitope–containing Bet v 1 fragments in patients with birch pollen allergy with and without atopic dermatitis (AD). Methods A clinical study was conducted in 15 patients with birch pollen allergy with AD (group 1), 5 patients with birch pollen allergy without AD (group 2), 5 allergic patients without birch pollen allergy (group 3), and 5 nonallergic subjects (group 4) by performing skin prick tests and APTs with rBet v 1 and hypoallergenic rBet v 1 fragments. T-cell, cutaneous lymphocyte antigen (CLA)+ and CCR4+ T-cell and cytokine responses were studied by thymidine uptake, carboxyfluorescein diacetate succinimidyl ester staining, and Luminex technology, respectively. Results rBet v 1 and hypoallergenic rBet v 1 fragments induced APT reactions in not only most of the patients with birch pollen allergy with AD (11/15) but also in most of those without AD (4/5). Patients with birch pollen allergy with AD had higher Bet v 1–specific proliferation of CLA+ and CCR4+ T cells compared with patients with birch pollen allergy without AD. There were no differences in Bet v 1–specific CLA+ and CCR4+ proliferation and cytokine secretion in patients with and without APT reactions. Conclusion Hypoallergenic rBet v 1 fragments induce T cell–dependent late reactions not only in patients with birch pollen allergy with AD but also in those without AD, which can be determined based on APT results but not based on in vitro parameters. PMID:26518092

  20. Peripheral blood lymphocyte typing as a useful tool to objectify the oral mucosa patch test in the diagnosis of allergic contact mucositis to nickel.

    PubMed

    Di Tola, Marco; Amodeo, Rachele; Marino, Mariacatia; Tabacco, Fabio; Casale, Rossella; Bove, Maurizio; Rossi, Alfredo; Cardelli, Patrizia; Picarelli, Antonio

    2014-06-01

    Nickel (Ni) exposure through the intestinal mucosa may cause a hypersensitivity reaction recently defined as allergic contact mucositis (ACM). This condition is identifiable by the oral mucosa patch test (omPT), a qualitative and subjective examination that requires clinical expertise. Our aim was to evaluate if a peripheral blood lymphocyte typing performed before and after the omPT for Ni may be able to objectify this examination for diagnostic purposes. Thirty patients with symptoms referable to the ingestion of Ni-rich foods were subjected to omPT for Ni. Before and after the omPT, each patient underwent blood sampling for the typing of total lymphocytes and their subsets (T, T helper or Th, T cytotoxic or Tc, B, natural killer or NK). Statistical analysis was performed by Student t test and receiver operating characteristic (ROC) curve analysis. According to the omPT outcomes, 18 patients were defined as Ni-sensitive and the remaining 12 as controls. In Ni-sensitive patients, the number of total, T, Th, Tc, and B lymphocytes/μL whole blood increased after the omPT (p<0.0001 for the first three, p=0.0004 and p=0.0001 for the last two lymphocyte types). No omPT-dependent lymphocyte increase was observed in controls. The post/pre omPT cell ratio, especially if calculated for Th lymphocytes, appears to be an effective index for diagnostic purposes (sensitivity=100%, specificity=83.3%, Youden index=0.833, area under curve (AUC)=0.926, p<0.0001). In conclusion, the peripheral blood lymphocyte typing with calculation of post/pre omPT cell ratio has the potential to support the omPT in diagnosing ACM, with the advantage of providing quantitative and objective data.

  1. Lidocaine Transdermal Patch

    MedlinePlus

    Lidocaine patches are used to relieve the pain of post-herpetic neuralgia (PHN; the burning, stabbing pains, ... for months or years after a shingles infection). Lidocaine is in a class of medications called local ...

  2. DyninstAPI Patches

    SciTech Connect

    LeGendre, M.

    2012-04-01

    We are seeking a code review of patches against DyninstAPI 8.0. DyninstAPI is an open source binary instrumentation library from the University of Wisconsin and University of Maryland. Our patches port DyninstAPI to the BlueGene/P and BlueGene/Q systems, as well as fix DyninstAPI bugs and implement minor new features in DyninstAPI.

  3. Identification of causative chemicals of allergic contact dermatitis using a combination of patch testing in patients and chemical analysis. Application to cases from rubber footwear.

    PubMed

    Kaniwa, M A; Isama, K; Nakamura, A; Kantoh, H; Itoh, M; Miyoshi, K; Saito, S; Shono, M

    1994-01-01

    5 cases of allergic contact dermatitis from rubber footwear were investigated by a combination of patch testing in patients and chemical analysis of causative rubber products. Our studies revealed 2-mercaptobenzothiazole (MBT) and benzothiazyl disulfide (MBTS) (typical allergenic accelerators) as causative chemicals in 3 cases from children's rubber shoes, ladies' rubber boots and ladies' canvas shoes. These 3 patients reacted to mercaptobenzothiazole-type accelerators including MBT and MBTS. MBT and MBTS were determined in each item of causative footwear by chemical analysis, including extraction by shaking with acetone-chloroform (1:1) mixture at room temperature and determination using reversed-phase high-performance liquid chromatography (RP-HPLC). Subsequently, we identified styrenated phenol (SP), a newly found allergenic antioxidant, as a causative chemical in a case from ladies' canvas shoes. The patient reacted to SP but not to MBT and MBTS, though SP, MBT and MBTS were determined in the causative shoes by gas chromatography (GC), GC-mass spectrometry (GC-MS) and HPLC. We also identified p-tert-butylphenol-formaldehyde resin (PTBP-F-R), (a known allergenic adhesive ingredient) as a causative chemical in a case from ladies' sneakers. The patient reacted to PTBP-F-R but not to p-tert-butylphenol (PTBP), MBT and MBTS. These 4 compounds were determined in the causative sneakers by GC, GC-MS and HPLC. Thus, our studies revealed that not only known allergens, such as MBT, MBTS and PTBP-F-R, but also a newly found one, such as SP, were important causes of allergic contact dermatitis from rubber footwear.

  4. Development and evaluation of a tampering resistant transdermal fentanyl patch.

    PubMed

    Cai, Bing; Engqvist, Håkan; Bredenberg, Susanne

    2015-07-05

    With the increasing number of misuse and abuse of opioids, the resistance to tampering becomes an important attribute for transdermal opioid patches. In this study, drug-containing geopolymer granules were integrated into an adhesive matrix to improve the resistance of fast drug release against some common abuse techniques. Bench testing showed that fentanyl loaded geopolymer granules had better resistance to tampering compared to a commercial fentanyl patch. Moreover, in a pilot in vivo study on a few rats, the granules showed potential to give similar drug plasma concentrations as the commercial fentanyl patch. After integrating geopolymer granules into an adhesive matrix, the new patch showed a better resistance against the investigated tampering tests compared with the commercially available patch. In this study, we showed that incorporating drug loaded geopolymer granules into a patch adhesive has potential to improve the resistance of the fentanyl patch against tampering without compromising the drug release.

  5. Sperm Patch-Clamp

    PubMed Central

    Lishko, Polina; Clapham, David E.; Navarro, Betsy; Kirichok, Yuriy

    2014-01-01

    Sperm intracellular pH and calcium concentration ([Ca2+]i) are two central factors that control sperm activity within the female reproductive tract. As such, the ion channels of the sperm plasma membrane that alter intracellular sperm [Ca2+] and pH play important roles in sperm physiology and the process of fertilization. Indeed, sperm ion channels regulate sperm motility, control sperm chemotaxis toward the egg in some species, and may trigger the acrosome reaction. Until recently, our understanding of these important molecules was rudimentary due to the inability to patch-clamp spermatozoa and directly record the activity of these ion channels under voltage clamp. Recently, we overcame this technical barrier and developed a method for reproducible application of the patch-clamp technique to mouse and human spermatozoa. This chapter covers important aspects of application of the patch-clamp technique to spermatozoa, such as selection of the electrophysiological equipment, isolation of spermatozoa for patch-clamp experiments, formation of the gigaohm seal with spermatozoa, and transition into the whole-cell mode of recording. We also discuss potential pitfalls in application of the patch-clamp technique to flagellar ion channels. PMID:23522465

  6. Chamber Tests with Human Subjects XX. Hypersensitivity to H as Demonstrated by Patch Tests Before and After Chamber Exposure to H Vapor

    DTIC Science & Technology

    1946-05-15

    intense erythema 4 a. erythema with edema b. dry scaling of scrotum c. maceration of axillary skin 5 a. vesicle b. numerous pinpoint vesicles c. crusting... skin reaction following exposure to H vapor in the man-chamber are discussed. Eight kodachrone prints, illustrating pertinent features, are included...Reactions for a Given Test Dose - 12 F. Changes in Threshold ------------------ 12 G. Abnormal Skin Reactions Following Chamber Exposures to H Vapor

  7. Research and analysis of patch shape on microstrip patch antenna

    NASA Astrophysics Data System (ADS)

    Ji, Ai-guo; Wang, Peng

    2017-01-01

    The shape of the radiating patch in the microstrip patch antenna is one of the many factors that affect the performance of the microstrip antenna.In this paper, on the premise of center frequency of 2.45 GHz, rectangular, circular and triangular microstrip patch antennas are designed and simulated respectively.The simulation results of the three microstrip patch antenna are analyzed, such as feed point position, return loss and radiation patterns.The influence of the shape of the radiation patch on the impedance bandwidth, gain and directivity of microstrip antennas is discussed.The simulation results show that the comprehensive performance of rectangular microstrip patch antenna is better than the other two, the comprehensive performance of triangular microstrip patch antenna is poor.

  8. Understanding patch departure rules for large carnivores: lion movements support a patch-disturbance hypothesis.

    PubMed

    Valeix, Marion; Chamaillé-Jammes, Simon; Loveridge, Andrew J; Davidson, Zeke; Hunt, Jane E; Madzikanda, Hillary; Macdonald, David W

    2011-08-01

    We test two hypotheses that could account for patch departure by large mammalian carnivores. One hypothesis is the unsuccessful-hunt hypothesis, where carnivores leave an area after an unsuccessful hunt but continue hunting in the same area after a successful hunt. The second hypothesis is the patch-disturbance hypothesis, where carnivores depart the area after a successful hunt because of behavioral responses of prey to predator presence. We used global positioning system collars to monitor the movements of African lions (Panthera leo) and identified their kill sites to distinguish between these two hypotheses. Lions moved to a different area (≥ 5 km away) after 87% of the kills, which supports the patch-disturbance hypothesis for patch-departure behavior of large mammalian carnivores.

  9. Comparative study of patches for liquid cooled garments.

    NASA Technical Reports Server (NTRS)

    Shitzer, A.; Chambers, A. B.

    1973-01-01

    Tests were performed on 12 cooling patches of various designs to establish criteria for the evaluation of their performance in liquid-cooled suits in industrial, military and aerospace applications. The thermal effectiveness value was 0.088 for patch designs with a double spiral flow pattern, and 0.075 for patch designs with a parallel flow pattern. The ratio of thermal energy transfer rate to cooling-medium pumping power requirement is indicated as the prime performance characteristic to be considered in the selection and rating of cooling patches.

  10. Polar Cap Patch Dynamics

    DTIC Science & Technology

    2013-04-25

    3 . Campaign periods for the 2010/2011 winter 3.1 Operation periods Ny-Ålesund 29 Nov - 13 Dec 2010 28 Dec - 10 Jan 2011 25 Jan - 8 Feb...dominated by a stable interplanetary magnetic field (IMF) B z < 0 and by an IMF B y > 0 situation. The aurora was characterized by a series of PMAFs...Svalbard Radar of two intense polar cap patch events on 6 February 2001. The interplanetary magnetic field (IMF) was dominated by a large positive By

  11. Patch antenna terahertz photodetectors

    SciTech Connect

    Palaferri, D.; Todorov, Y. Chen, Y. N.; Madeo, J.; Vasanelli, A.; Sirtori, C.; Li, L. H.; Davies, A. G.; Linfield, E. H.

    2015-04-20

    We report on the implementation of 5 THz quantum well photodetector exploiting a patch antenna cavity array. The benefit of our plasmonic architecture on the detector performance is assessed by comparing it with detectors made using the same quantum well absorbing region, but processed into a standard 45° polished facet mesa. Our results demonstrate a clear improvement in responsivity, polarization insensitivity, and background limited performance. Peak detectivities in excess of 5 × 10{sup 12} cmHz{sup 1/2}/W have been obtained, a value comparable with that of the best cryogenic cooled bolometers.

  12. Patched Conic Trajectory Code

    NASA Technical Reports Server (NTRS)

    Park, Brooke Anderson; Wright, Henry

    2012-01-01

    PatCon code was developed to help mission designers run trade studies on launch and arrival times for any given planet. Initially developed in Fortran, the required inputs included launch date, arrival date, and other orbital parameters of the launch planet and arrival planets at the given dates. These parameters include the position of the planets, the eccentricity, semi-major axes, argument of periapsis, ascending node, and inclination of the planets. With these inputs, a patched conic approximation is used to determine the trajectory. The patched conic approximation divides the planetary mission into three parts: (1) the departure phase, in which the two relevant bodies are Earth and the spacecraft, and where the trajectory is a departure hyperbola with Earth at the focus; (2) the cruise phase, in which the two bodies are the Sun and the spacecraft, and where the trajectory is a transfer ellipse with the Sun at the focus; and (3) the arrival phase, in which the two bodies are the target planet and the spacecraft, where the trajectory is an arrival hyperbola with the planet as the focus.

  13. Statistics for Patch Observations

    NASA Astrophysics Data System (ADS)

    Hingee, K. L.

    2016-06-01

    In the application of remote sensing it is common to investigate processes that generate patches of material. This is especially true when using categorical land cover or land use maps. Here we view some existing tools, landscape pattern indices (LPI), as non-parametric estimators of random closed sets (RACS). This RACS framework enables LPIs to be studied rigorously. A RACS is any random process that generates a closed set, which encompasses any processes that result in binary (two-class) land cover maps. RACS theory, and methods in the underlying field of stochastic geometry, are particularly well suited to high-resolution remote sensing where objects extend across tens of pixels, and the shapes and orientations of patches are symptomatic of underlying processes. For some LPI this field already contains variance information and border correction techniques. After introducing RACS theory we discuss the core area LPI in detail. It is closely related to the spherical contact distribution leading to conditional variants, a new version of contagion, variance information and multiple border-corrected estimators. We demonstrate some of these findings on high resolution tree canopy data.

  14. Improved Gain Microstrip Patch Antenna

    DTIC Science & Technology

    2015-08-06

    08-2015 Publication Improved Gain Microstrip Patch Antenna David A. Tonn Naval Under Warfare Center Division, Newport 1176 Howell St., Code 00L...Distribution A An antenna for mounting on a ground plane includes a dielectric substrate for mounting on the ground plane. A conductive patch...GAIN MICROSTRIP PATCH ANTENNA STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and used by or for the

  15. Ethinyl Estradiol and Norelgestromin Transdermal Patch

    MedlinePlus

    ... the skin. One patch is applied once a week for 3 weeks, followed by a patch-free week. Follow the directions on your prescription label carefully, ... new patch on the same day of the week (the Patch Change Day). Apply a new patch ...

  16. Analgesic Microneedle Patch for Neuropathic Pain Therapy.

    PubMed

    Xie, Xi; Pascual, Conrado; Lieu, Christopher; Oh, Seajin; Wang, Ji; Zou, Bende; Xie, Julian; Li, Zhaohui; Xie, James; Yeomans, David C; Wu, Mei X; Xie, Xinmin Simon

    2017-01-24

    Neuropathic pain caused by nerve injury is debilitating and difficult to treat. Current systemic pharmacological therapeutics for neuropathic pain produce limited pain relief and have undesirable side effects, while current local anesthetics tend to nonspecifically block both sensory and motor functions. Calcitonin gene related peptide (CGRP), a neuropeptide released from sensory nerve endings, appears to play a significant role in chronic neuropathic pain. In this study, an analgesic microneedle (AMN) patch was developed using dissolvable microneedles to transdermally deliver selective CGRP antagonist peptide in a painless manner for the treatment of localized neuropathic pain. Local analgesic effects were evaluated in rats by testing behavioral pain sensitivity in response to thermal and mechanical stimuli using neuropathic pain models such as spared-nerve injury and diabetic neuropathy pain, as well as neurogenic inflammatory pain model induced by ultraviolet B (UVB) radiation. Unlike several conventional therapies, the AMN patches produced effective analgesia on neuropathic pain without disturbing the normal nociception and motor function of the rat, resulting from the high specificity of the delivered peptide against CGRP receptors. The AMN patches did not cause skin irritation or systemic side effects. These results demonstrate that dissolvable microneedle patches delivering CGRP antagonist peptide provide an effective, safe, and simple approach to mitigate neuropathic pain with significant advantages over current treatments.

  17. Whole-GUV patch-clamping.

    PubMed

    Garten, Matthias; Mosgaard, Lars D; Bornschlögl, Thomas; Dieudonné, Stéphane; Bassereau, Patricia; Toombes, Gilman E S

    2017-01-10

    Studying how the membrane modulates ion channel and transporter activity is challenging because cells actively regulate membrane properties, whereas existing in vitro systems have limitations, such as residual solvent and unphysiologically high membrane tension. Cell-sized giant unilamellar vesicles (GUVs) would be ideal for in vitro electrophysiology, but efforts to measure the membrane current of intact GUVs have been unsuccessful. In this work, two challenges for obtaining the "whole-GUV" patch-clamp configuration were identified and resolved. First, unless the patch pipette and GUV pressures are precisely matched in the GUV-attached configuration, breaking the patch membrane also ruptures the GUV. Second, GUVs shrink irreversibly because the membrane/glass adhesion creating the high-resistance seal (>1 GΩ) continuously pulls membrane into the pipette. In contrast, for cell-derived giant plasma membrane vesicles (GPMVs), breaking the patch membrane allows the GPMV contents to passivate the pipette surface, thereby dynamically blocking membrane spreading in the whole-GMPV mode. To mimic this dynamic passivation mechanism, beta-casein was encapsulated into GUVs, yielding a stable, high-resistance, whole-GUV configuration for a range of membrane compositions. Specific membrane capacitance measurements confirmed that the membranes were truly solvent-free and that membrane tension could be controlled over a physiological range. Finally, the potential for ion transport studies was tested using the model ion channel, gramicidin, and voltage-clamp fluorometry measurements were performed with a voltage-dependent fluorophore/quencher pair. Whole-GUV patch-clamping allows ion transport and other voltage-dependent processes to be studied while controlling membrane composition, tension, and shape.

  18. Blockade of patch-based μ opioid receptors in the striatum attenuates methamphetamine-induced conditioned place preference and reduces activation of the patch compartment.

    PubMed

    Horner, Kristen A; Logan, Mary Caroline; Fisher, Trevor J; Logue, Jordan B

    2017-02-05

    The behavioral effects of methamphetamine (METH) are mediated by the striatum, which is divided into the patch compartment, which mediates limbic and reward functions, and the matrix compartment, which mediates sensorimotor tasks. METH treatment results in repetitive behavior that is related to enhanced relative activation of the patch versus the matrix compartment. The patch, but not the matrix compartment contains a high density of μ opioid receptors, and localized blockade of patch-based μ opioid receptors attenuates METH-induced patch-enhanced activity and repetitive behaviors. Numerous studies have examined patch-enhanced activity and the contribution of patch-associated μ opioid receptors to METH-induced repetitive behavior, but it is not known whether patch-enhanced activity occurs during METH-mediated reward, nor is it known if patch-based μ opioid receptors contribute to METH reward. The goals of this study were to determine if blockade of patch-based μ opioid receptors alters METH-induced conditioned place preference (CPP), as well activation of the patch and matrix compartments following METH-mediated CPP. A biased conditioning paradigm was used to assess CPP, and conditioning occurred over an 8-d period. Animals were bilaterally infused in the striatum with the μ-specific antagonist CTAP or vehicle prior to conditioning. Animals were tested for preference 24h after the last day of conditioning, sacrificed and the brains processed for immunohistochemistry. Blockade of patch-based μ opioid receptors reduced METH-induced CPP, and reduced patch-enhanced c-Fos expression in the striatum following METH-mediated CPP. These data indicate that patch-enhanced activity is associated with METH-mediated reward and patch-based μ opioid receptors contribute to this phenomenon.

  19. Structural health monitoring of composite repair patches in bridge rehabilitation

    NASA Astrophysics Data System (ADS)

    Wu, Zhanjun; Ghosh, Kumar; Qing, Xinlin; Karbhari, Vistasp; Chang, Fu-Kuo

    2006-03-01

    In recent years, there are many issues involving safety on old bridges, aircrafts and other structures, which threaten the lives of the people using those structures, as well as the structures themselves. To prevent future failure, various measures are being taken. Structure rehabilitations with carbon fiber reinforced composite patches have been adopted and demonstrated to be an excellent way to enhance/repair the structures and prolong the service life. However, there are still many problems residing in this kind of technology that remain unsolved, for example, the failure of the interface between composite repair patches and their host structures. This is a critical issue that must be addressed in order to show the viability of composite patches. In order to study debond occurring between composite repair patches and their host structures, a structure health monitoring scheme was demonstrated on a concrete bridge model in the laboratory. The system is based on active sensing with diagnostic lamb waves, in which piezoelectric transducers are used as both sensors and actuators. In the test, six SMART Layers, each having eight piezoelectirc transducers, were integrated with two composite repair strips on the deck slab of the concrete bridge model. For the three diagnostic layers with each composite repair patch, two layers were bonded on the top surface of the patch, and the other is embedded at the interface between the composite repair patch and the deck slab of the concrete bridge model. The loading procedure of the test included three phases. First, the bridge model was preloaded to initiate cracks on the deck slabs and the repair patches were then implemented. Second, the load was raised to reach the shear capacity of the girders of the bridge model and then the repair patches were implemented on those girders. Lastly, the structure was loaded to damage the deck slabs. During the test, the initiation and development of debond between composite repair patches

  20. Allergy Skin Tests

    MedlinePlus

    ... allergic rhinitis) Allergic asthma Dermatitis (eczema) Food allergies Penicillin allergy Bee venom allergy Latex allergy Skin tests are ... may recommend this test to check for an allergy to insect venom or penicillin. Patch test Patch testing is generally done to ...

  1. Taro corms mucilage/HPMC based transdermal patch: an efficient device for delivery of diltiazem hydrochloride.

    PubMed

    Sarkar, Gunjan; Saha, Nayan Ranjan; Roy, Indranil; Bhattacharyya, Amartya; Bose, Madhura; Mishra, Roshnara; Rana, Dipak; Bhattacharjee, Debashis; Chattopadhyay, Dipankar

    2014-05-01

    The aim of this work is to examine the effectiveness of mucilage/hydroxypropylmethylcellulose (HPMC) based transdermal patch (matrix type) as a drug delivery device. We have successfully extracted mucilage from Colocasia esculenta (Taro) corms and prepared diltiazem hydrochloride incorporated mucilage/HPMC based transdermal patches using various wt% of mucilage by the solvent evaporation technique. Characterization of both mucilage and transdermal patches has been done by several techniques such as Molisch's test, organoleptic evaluation of mucilage, mechanical, morphological and thermal analysis of transdermal patches. Skin irritation test is studied on hairless Albino rat skin showing that transdermal patches are apparently free of potentially hazardous skin irritation. Fourier transform infrared analysis shows that there is no interaction between drug, mucilage and HPMC while scanning electron microscopy shows the surface morphology of transdermal patches. In vitro drug release time of mucilage-HPMC based transdermal patches is prolonged with increasing mucilage concentration in the formulation.

  2. Failure analysis and surety design of composite patching systems.

    SciTech Connect

    Hamoush, Sameer

    2004-08-01

    This work presents an experimental evaluation of patch repair of solid laminated composites. The study was focused on destructive and nondestructive tests of full-scale repaired panels under static tension loading conditions. The testing program consisted of ten panels: three pristine, three damaged, three repaired and one repaired with mismatched fiber orientation patch. The evaluated panels were (300 mm x 675 mm) in size and consisted of 6-ply ((-60 /60/0){sub s}) quasi-isotropic laminates. The destructive tests were performed by North Carolina A&T State University and the nondestructive tests were performed by Iowa State University using Pulse-echo C-scan, Air coupled TTU and Auto-Tap. Sandia National Laboratories validated the NDT tests by implementing NDE field methods. Based on the evaluation performed in this study, it appears that the patch repair is an effective means in retrofitting damaged solid composite laminates.

  3. Shape of patch edges affects edge permeability for meadow voles.

    PubMed

    Nams, Vilis O

    2012-09-01

    Human development typically fragments natural habitats into patches, affecting population and metapopulation dynamics via changes in animal behavior. Emigration from one habitat patch to another has a large effect on population and metapopulation dynamics. One factor that affects emigration is permeability of patch edges. This study looks at the effects of edge shape (convex, concave, and straight) on edge permeability for meadow voles (Microtus pennsylvanicus).. I tested five hypotheses for responses of animal movement to patch shape: (1) neutral edge response; (2) edge attraction; (3) edge avoidance; (4) time-minimizing, in which an animal attempts to minimize the time spent in inhospitable matrix, and thus travels as far as possible in the patch before crossing the edge; and (5) protection, in which an animal attempts to maximize protection while in the inhospitable matrix by keeping the patch close by. These hypotheses were tested by an experimental manipulation of meadow vole habitats. A strip was mowed with different edge shapes through an old field, and vole response was measured by tracking plates. Voles crossed edges at concave treatments twice as often compared to convex and straight shapes. Hypotheses (2) and (5) were supported. Although edge attraction causes a passive effect of a decrease in edge-crossing at concavities, this effect was eclipsed by the active effect of voles choosing to cross at concavities. The results can be generalized to edge tortuosity in general. Conservation biologists should consider edge shapes when exploring the effects of habitat fragmentation on animal populations.

  4. Transdermal Buprenorphine Patches for Postoperative Pain Control in Abdominal Surgery

    PubMed Central

    Kumar, Santosh; Singh, Prithvi Kumar; Verma, Reetu; Chandra, Girish; Bhatia, Vinod Kumar; Singh, Dinesh; Bogra, Jaishri

    2016-01-01

    Introduction Buprenorphine is a semi-synthetic derivative of thebaine; its low concentration is sufficient to provide effective pain relief. Aim To evaluate the efficacy of transdermal buprenorphine patch in postoperative pain management. Materials and Methods After ethical approval and taking informed consent from the patients, they were randomized into three groups (n=30 in each group) using a computer generated random number table. Group A: placebo patch; Group B: buprenorphine (10mg) patch and Group C: buprenorphine (20mg) patch. Haemodynamic and analgesic effects were compared by using analysis of variance (ANOVA) followed by Turkey’s post hoc test. The proportion of side effects was compared using the Chi-square test. Results Haemodynamic changes were not statistically different in all the three groups A, B and C, whereas at the end of surgery VAS score of Group A subjects was significantly higher (4.93±0.98) as compared to Group B (1.73±0.64) and Group C (1.40±0.50). On 2nd postoperative day, no pain was reported by the Group C patients and on 4th day after surgery, no pain was reported by Group B patients. Conclusion The transdermal buprenorphine patch (20mg) was effective in attenuating postoperative pain, maintaining haemodynamic stability requiring no rescue analgesia, with fewer postoperative rescue analgesic requirements in low dose of buprenorphine patch (10mg) group. PMID:27504383

  5. Patch Size and Isolation Predict Plant Species Density in a Naturally Fragmented Forest

    PubMed Central

    Munguía-Rosas, Miguel A.; Montiel, Salvador

    2014-01-01

    Studies of the effects of patch size and isolation on plant species density have yielded contrasting results. However, much of the available evidence comes from relatively recent anthropogenic forest fragments which have not reached equilibrium between extinction and immigration. This is a critical issue because the theory clearly states that only when equilibrium has been reached can the number of species be accurately predicted by habitat size and isolation. Therefore, species density could be better predicted by patch size and isolation in an ecosystem that has been fragmented for a very long time. We tested whether patch area, isolation and other spatial variables explain variation among forest patches in plant species density in an ecosystem where the forest has been naturally fragmented for long periods of time on a geological scale. Our main predictions were that plant species density will be positively correlated with patch size, and negatively correlated with isolation (distance to the nearest patch, connectivity, and distance to the continuous forest). We surveyed the vascular flora (except lianas and epiphytes) of 19 forest patches using five belt transects (50×4 m each) per patch (area sampled per patch = 0.1 ha). As predicted, plant species density was positively associated (logarithmically) with patch size and negatively associated (linearly) with patch isolation (distance to the nearest patch). Other spatial variables such as patch elevation and perimeter, did not explain among-patch variability in plant species density. The power of patch area and isolation as predictors of plant species density was moderate (together they explain 43% of the variation), however, a larger sample size may improve the explanatory power of these variables. Patch size and isolation may be suitable predictors of long-term plant species density in terrestrial ecosystems that are naturally and anthropogenically fragmented. PMID:25347818

  6. Smart patch piezoceramic actuator issues

    NASA Technical Reports Server (NTRS)

    Griffin, Steven F.; Denoyer, Keith K.; Yost, Brad

    1993-01-01

    The Phillips Laboratory is undertaking the challenge of finding new and innovative ways to integrate sensing, actuation, and the supporting control and power electronics into a compact self-contained unit to provide vibration suppression for a host structure. This self-contained unit is commonly referred to as a smart patch. The interfaces to the smart patch will be limited to standard spacecraft power and possibly a communications line. The effort to develop a smart patch involves both contractual and inhouse programs which are currently focused on miniaturization of the electronics associated with vibrational control using piezoceramic sensors and actuators. This paper is comprised of two distinct parts. The first part examines issues associated with bonding piezoceramic actuators to a host structure. Experimental data from several specimens with varying flexural stiffness are compared to predictions from two piezoelectric/substructure coupling models, the Blocked Force Model and the Uniform Strain Model with Perfect Bonding. The second part of the paper highlights a demonstration article smart patch created using the insights gained from inhouse efforts at the Phillips Laboratory. This demonstration article has self contained electronics on the same order of size as the actuator powered by a voltage differential of approximately 32 volts. This voltage is provided by four rechargeable 8 volt batteries.

  7. MS lesion segmentation using a multi-channel patch-based approach with spatial consistency

    NASA Astrophysics Data System (ADS)

    Mechrez, Roey; Goldberger, Jacob; Greenspan, Hayit

    2015-03-01

    This paper presents an automatic method for segmentation of Multiple Sclerosis (MS) in Magnetic Resonance Images (MRI) of the brain. The approach is based on similarities between multi-channel patches (T1, T2 and FLAIR). An MS lesion patch database is built using training images for which the label maps are known. For each patch in the testing image, k similar patches are retrieved from the database. The matching labels for these k patches are then combined to produce an initial segmentation map for the test case. Finally a novel iterative patch-based label refinement process based on the initial segmentation map is performed to ensure spatial consistency of the detected lesions. A leave-one-out evaluation is done for each testing image in the MS lesion segmentation challenge of MICCAI 2008. Results are shown to compete with the state-of-the-art methods on the MICCAI 2008 challenge.

  8. Monocular Patching May Induce Ipsilateral “Where” Spatial Bias

    PubMed Central

    Chen, Peii; Erdahl, Lillian; Barrett, Anna M.

    2009-01-01

    Spatial bias is an asymmetry of perception and/or representation of spatial information —“where” bias —, or of spatially directed actions — “aiming” bias. A monocular patch may induce contralateral “where” spatial bias (the Sprague effect; Sprague (1966) Science, 153, 1544–1547). However, an ipsilateral patch-induced spatial bias may be observed if visual occlusion results in top-down, compensatory re-allocation of spatial perceptual or representational resources toward the region of visual deprivation. Tactile distraction from a monocular patch may also contribute to an ipsilateral bias. To examine these hypotheses, neurologically normal adults bisected horizontal lines at baseline without a patch, while wearing a monocular patch, and while wearing tactile-only and visual-only monocular occlusion. We fractionated “where” and “aiming” spatial bias components using a video apparatus to reverse visual feedback for half of the test trials. The results support monocular patch-induced ipsilateral “where” spatial errors, which are not consistent with the Sprague effect. Further, the present findings suggested that the induced ipsilateral bias may be primarily induced by visual deprivation, consistent with compensatory “where” resource re-allocation. PMID:19100274

  9. Local spread of metamitron resistant Chenopodium album L. patches.

    PubMed

    Aper, J; De Riek, J; Mechant, E; Bulcke, R; Reheul, D

    2011-01-01

    Molecular markers can provide valuable information on the spread of resistant weed biotypes. In particular, tracing local spread of resistant weed patches will give details on the importance of seed migration with machinery, manure, wind or birds. This study investigated the local spread of metamitron resistant Chenopodium album L. patches in the southwest region of the province West-Flanders (Belgium). During the summer of 2009, leaf and seed samples were harvested in 27 patches, distributed over 10 sugar beet fields and 1 maize field. The fields were grouped in four local clusters. Each cluster corresponded with the farmer who cultivated these fields. A cleaved amplified polymorphic sequence (CAPS) procedure identified the Ser264 to Gly mutation in the D1 protein, endowing resistance to metamitron, a key herbicide applied in sugar beet. The majority of the sampled plants within a patch (97% on average) carried this mutation. Amplified fragment length polymorphism (AFLP) analysis was performed with 4 primer pairs and yielded 270 molecular markers, polymorphic for the whole dataset (303 samples). Analysis of molecular variance revealed that a significant part of the genetic variability was attributed to variation among the four farmer locations (12 %) and variation among Chenopodium album patches within the farmer locations (14%). In addition, Mantel tests revealed a positive correlation between genetic distances (linearised phipt between pairs of patches) and geographic distances (Mantel-coefficient significant at p = 0.002), suggesting isolation-by-distance. In one field, a decreased genetic diversity and strong genetic relationships between all the patches in this field supported the hypothesis of a recent introduction of resistant biotypes. Furthermore, genetic similarity between patches from different fields from the same farmer and from different farmers indicated that seed transport between neighbouring fields is likely to have an important impact on the

  10. Habitat patch size and isolation as predictors of occupancy and number of argyrodine spider kleptoparasites in Nephila webs

    NASA Astrophysics Data System (ADS)

    Agnarsson, Ingi

    2011-02-01

    How fully a suitable habitat patch is utilized by organisms depends crucially on patch size and isolation. Testing this interplay is made difficult in many systems by the arbitrariness of defining a "habitat patch", measuring its boarders, and relatively low detection probability of the inhabitants. Spider webs as habitat patches for obligate web kleptoparasites are free from these problems. Each individual web is a highly discrete and readily measured habitat patch, and the detection probability of argyrodine spider kleptoparasites is very nearly 1. Hence, spider webs emerge as simple systems for ecological models such as patch occupancy and metapopulation biology. Recently, I showed that the distribution of kleptoparasites among host webs relates both to web (patch) size as well as patch connectivity. Here, I test the relative importance of patch size versus isolation in explaining patch occupancy and abundance of inhabitants. I find that (1) web size is the better predictor of patch occupancy and abundance. (2) Web size is overall positively correlated with abundance, but predicts it most precisely among interconnected webs and not at all among the most isolated webs. Hence, patch occupancy and inhabitant abundance is explained by a rather complex interplay between patch size and isolation.

  11. Habitat patch size and isolation as predictors of occupancy and number of argyrodine spider kleptoparasites in Nephila webs.

    PubMed

    Agnarsson, Ingi

    2011-02-01

    How fully a suitable habitat patch is utilized by organisms depends crucially on patch size and isolation. Testing this interplay is made difficult in many systems by the arbitrariness of defining a "habitat patch", measuring its boarders, and relatively low detection probability of the inhabitants. Spider webs as habitat patches for obligate web kleptoparasites are free from these problems. Each individual web is a highly discrete and readily measured habitat patch, and the detection probability of argyrodine spider kleptoparasites is very nearly 1. Hence, spider webs emerge as simple systems for ecological models such as patch occupancy and metapopulation biology. Recently, I showed that the distribution of kleptoparasites among host webs relates both to web (patch) size as well as patch connectivity. Here, I test the relative importance of patch size versus isolation in explaining patch occupancy and abundance of inhabitants. I find that (1) web size is the better predictor of patch occupancy and abundance. (2) Web size is overall positively correlated with abundance, but predicts it most precisely among interconnected webs and not at all among the most isolated webs. Hence, patch occupancy and inhabitant abundance is explained by a rather complex interplay between patch size and isolation.

  12. Tunable Patch Antennas Using Microelectromechanical Systems

    DTIC Science & Technology

    2011-05-11

    Tunable Microstrip Patch Antena Using RF MEMS Technology, IEEE Transactions on Antennas and Propagations, Vol. 55, Issue 4, April 2007, pp. 1193...capacitors co-fabricated in the same process. 15. SUBJECT TERMS Microstrip antennas, patch antennas, radio frequency microelectromechanical systems...resonant mode. Keywords: Microstrip antennas, patch antennas, radio frequency microelectromechanical systems, tunable circuits and devices 2

  13. OpenSSO Project Patches

    SciTech Connect

    NEBERGALL, CHRISTOPHER

    2009-06-08

    These are patches to Sun Microsystems open source OpenSSO project to fix various bugs and incorporate changes for Sandia and NNSA to use the product including fixes to improve OpenSSO's authentication and authorization abilities. These fixes will then by incorporated by Sun into their Sun Access Manager product, which is used by various DOE/NNSA plants and labs. Having Sun maintain these changes will relieve SNL and DOE from the cost of maintaining the changes themselves.

  14. Foraging decisions, patch use, and seasonality in egrets (Aves: ciconiiformes)

    USGS Publications Warehouse

    Erwin, R.M.

    1985-01-01

    Feeding snowy (Egretta thula) and great (Casmerodius albus) egrets were observed during 2 breeding seasons in coastal New Jersey and 2 brief winter periods in northeast Florida (USA). A number of tests based on assumptions of foraging models, predictions from foraging theory, and earlier empirical tests concerning time allocation and movement in foraging patches was made. Few of the expectations based on foraging theory and/or assumptions were supported by the empirical evidence. Snowy egrets fed with greater intensity and efficiency during the breeding season (when young were being fed) than during winter. They also showed some tendency to leave patches when their capture rate declined, and they spent more time foraging in patches when other birds were present nearby. Great egrets showed few of these tendencies, although they did leave patches when their intercapture intervals increased. Satiation differences had some influence on feeding rates in snowy egrets, but only at the end of feeding bouts. Some individuals of both species revisited areas in patches that had recently been exploited, and success rates were usually higher after the 2nd visit. Apparently, for predators of active prey, short-term changes in resource availability ('resource depression') may be more important than resource depletion, a common assumption in most optimal foraging theory models.

  15. "Patch"ing up our tumor signaling knowledge.

    PubMed

    Atwood, Scott X; Whitson, Ramon J; Oro, Anthony E

    2013-05-01

    The tumor suppressor Patched1 (Ptch1) possesses well-described roles in regulating sonic hedgehog (SHH) signaling in the skin and preventing the formation of basal cell carcinomas (BCCs). In this issue, Kang et al. extend their previous work to show that a naturally occurring allele of Ptch1 found in FVB mice promotes early squamous cell carcinoma (SCC) growth without aberrant activation of the SHH pathway. The study reveals new roles for Ptch1 that lie at the nexus between BCC and SCC formation.

  16. Mitral Valve Mechanics Following Posterior Leaflet Patch Augmentation

    PubMed Central

    Rahmani, Azadeh; Rasmussen, Ann Q.; Honge, Jesper L.; Ostli, Bjorn; Levine, Robert A.; Hagège, Albert; Nygaard, Hans; Nielsen, Sten L.; Jensen, Morten O.

    2013-01-01

    Background and aim of the study Attention towards the optimization of mitral valve repair methods is increasing. Patch augmentation is one strategy used to treat functional ischemic mitral regurgitation (FIMR). The study aim was to investigate the force balance changes in specific chordae tendineae emanating from the posterior papillary muscle in a FIMR-simulated valve, following posterior leaflet patch augmentation. Methods Mitral valves were obtained from 12 pigs (body weight 80 kg). An in vitro test set-up simulating the left ventricle was used to hold the valves. The left ventricular pressure was regulated with water to simulate different static pressures during valve closure. A standardized oval pericardial patch (17 × 29 mm) was introduced into the posterior leaflet from mid P2 to the end of the P3 scallop. Dedicated miniature transducers were used to record the forces exerted on the chordae tendineae. Data were acquired before and after 12 mm posterior and 5 mm apical posterior papillary muscle displacement to simulate the effect from one of the main contributors of FIMR, before and after patch augmentation. Results The effect of displacing the posterior papillary muscle induced tethering on the intermediate chordae tendineae to the posterior leaflet, and resulted in a 39.8% force increase (p = 0.014). Posterior leaflet patch augmentation of the FIMR valve induced a 31.1% force decrease (p = 0.007). There was no difference in force between the healthy and the repaired valve simulations (p = 0.773). Conclusion Posterior leaflet patch augmentation significantly reduced the forces exerted on the intermediate chordae tendineae from the posterior papillary muscle following FIMR simulation. As changes in chordal tension lead to a redistribution of the total stress exerted on the valve, patch augmentation may have an adverse long-term influence on mitral valve function and remodeling. PMID:23610985

  17. A nanofibrous electrospun patch to maintain human mesenchymal cell stemness.

    PubMed

    Pandolfi, L; Furman, N Toledano; Wang, Xin; Lupo, C; Martinez, J O; Mohamed, M; Taraballi, F; Tasciotti, E

    2017-03-01

    Mesenchymal stem cells (MSCs) have been extensively investigated in regenerative medicine because of their crucial role in tissue healing. For these properties, they are widely tested in clinical trials, usually injected in cell suspension or in combination with tridimensional scaffolds. However, scaffolds can largely affect the fates of MSCs, inducing a progressive loss of functionality overtime. The ideal scaffold must delay MSCs differentiation until paracrine signals from the host induce their change. Herein, we proposed a nanostructured electrospun gelatin patch as an appropriate environment where human MSCs (hMSCs) can adhere, proliferate, and maintain their stemness. This patch exhibited characteristics of a non-linear elastic material and withstood degradation up to 4 weeks. As compared to culture and expansion in 2D, hMSCs on the patch showed a similar degree of proliferation and better maintained their progenitor properties, as assessed by their superior differentiation capacity towards typical mesenchymal lineages (i.e. osteogenic and chondrogenic). Furthermore, immunohistochemical analysis and longitudinal non-invasive imaging of inflammatory response revealed no sign of foreign body reaction for 3 weeks. In summary, our results demonstrated that our biocompatible patch favored the maintenance of undifferentiated hMSCs for up to 21 days and is an ideal candidate for tridimensional delivery of hMSCs. The present work reports a nanostructured patch gelatin-based able to maintain in vitro hMSCs stemness features. Moreover, hMSCs were able to differentiate toward osteo- and chondrogenic lineages once induces by differentiative media, confirming the ability of this patch to support stem cells for a potential in vivo application. These attractive properties together with the low inflammatory response in vivo make this patch a promising platform in regenerative medicine.

  18. Analysis of Stub Loaded Microstrip Patch Antennas

    NASA Technical Reports Server (NTRS)

    Bailey, M. C.; Deshpande, M. D.

    1997-01-01

    A microstrip patch antenna fed by a coaxial probe and reactively loaded by a open circuited microstrip line has been used previously to produce circular polarization[ l] and also as a building block for a series fed microstrip patch array [2]. Rectangular and circular patch antennas loaded with a microstrip stub were previously analyzed using the generalized Thevenin theorem [2,3]. In the Thevenin theorem approach, the mutual coupling between the patch current and the surface current on the stub was not taken into account. Also, the Thevenin theorem approach neglects continuity of current at the patch-stub junction. The approach in this present paper includes the coupling between the patch and stub currents as well as continuity at the patch-stub junction.

  19. Data-driven interactive 3D medical image segmentation based on structured patch model.

    PubMed

    Park, Sang Hyun; Yun, Il Dong; Lee, Sang Uk

    2013-01-01

    In this paper, we present a novel three dimensional interactive medical image segmentation method based on high level knowledge of training set. Since the interactive system should provide intermediate results to an user quickly, insufficient low level models are used for most of previous methods. To exploit the high level knowledge within a short time, we construct a structured patch model that consists of multiple corresponding patch sets. The structured patch model includes the spatial relationships between neighboring patch sets and the prior knowledge of the corresponding patch set on each local region. The spatial relationships accelerate the search of corresponding patch in test time, while the prior knowledge improves the segmentation accuracy. The proposed framework provides not only fast editing tool, but the incremental learning system through adding the segmentation result to the training set. Experiments demonstrate that the proposed method is useful for fast and accurate segmentation of target objects from the multiple medical images.

  20. A large-scale deforestation experiment: Effects of patch area and isolation on Amazon birds

    USGS Publications Warehouse

    Ferraz, G.; Nichols, J.D.; Hines, J.E.; Stouffer, P.C.; Bierregaard, R.O.; Lovejoy, T.E.

    2007-01-01

    As compared with extensive contiguous areas, small isolated habitat patches lack many species. Some species disappear after isolation; others are rarely found in any small patch, regardless of isolation. We used a 13-year data set of bird captures from a large landscape-manipulation experiment in a Brazilian Amazon forest to model the extinction-colonization dynamics of 55 species and tested basic predictions of island biogeography and metapopulation theory. From our models, we derived two metrics of species vulnerability to changes in isolation and patch area. We found a strong effect of area and a variable effect of isolation on the predicted patch occupancy by birds.

  1. A large-scale deforestation experiment: effects of patch area and isolation on Amazon birds.

    PubMed

    Ferraz, Gonçalo; Nichols, James D; Hines, James E; Stouffer, Philip C; Bierregaard, Richard O; Lovejoy, Thomas E

    2007-01-12

    As compared with extensive contiguous areas, small isolated habitat patches lack many species. Some species disappear after isolation; others are rarely found in any small patch, regardless of isolation. We used a 13-year data set of bird captures from a large landscape-manipulation experiment in a Brazilian Amazon forest to model the extinction-colonization dynamics of 55 species and tested basic predictions of island biogeography and metapopulation theory. From our models, we derived two metrics of species vulnerability to changes in isolation and patch area. We found a strong effect of area and a variable effect of isolation on the predicted patch occupancy by birds.

  2. Omnidirectional Lamb waves by axisymmetrically-configured magnetostrictive patch transducer.

    PubMed

    Lee, Joo Kyung; Kim, Hoe Woong; Kim, Yoon Young

    2013-09-01

    This work presents the generation of omnidirectional Lamb waves by a new magnetostrictive patch transducer (MPT) and investigates its generation mechanism. Although MPTs have been widely used for wave transduction in plates and pipes, no investigation reports the generation of omnidirectional Lamb waves in a plate by an MPT. For the generation, we propose an axisymmetrically-configured MPT that installs multiple axisymmetric turns of coil outside of a permanent cylindrical magnet located above the center of a circular magnetostrictive patch. After confirming the omnidirectivity of the proposed MPT experimentally, the mechanism of the Lamb wave generation and its frequency characteristics are investigated. It is also shown that the Lamb wave is most efficiently generated in a test plate when its wavelength is equal to two-thirds of the magnetostrictive patch diameter. If this wavelength¿patch diameter relation holds, the second radial extensional vibration mode of the patch of the proposed MPT is shown to be the mode responsible for generating the Lamb wave in a plate.

  3. Temporary patching of damaged UF{sub 6} cylinders

    SciTech Connect

    Cardenas, A.L.

    1991-12-31

    Patching techniques based on application of epoxy resins have been developed for temporarily repairing UF{sub 6} cylinders which have sustained relatively minor damage and must be safely emptied. The method is considerably faster and simpler than metallurgical weld repairs. Laboratory tests, detailed operational procedures, and case histories of experience at the Portsmouth Gaseous Diffusion Plant are described.

  4. Face recognition under variable illumination via sparse representation of patches

    NASA Astrophysics Data System (ADS)

    Fan, Shouke; Liu, Rui; Feng, Weiguo; Zhu, Ming

    2013-10-01

    The objective of this work is to recognize faces under variations in illumination. Previous works have indicated that the variations in illumination can dramatically reduce the performance of face recognition. To this end - ;an efficient method for face recognition which is robust under variable illumination is proposed in this paper. First of all, a discrete cosine transform(DCT) in the logarithm domain is employed to preprocess the images, removing the illumination variations by discarding an appropriate number of low-frequency DCT coefficients. Then, a face image is partitioned into several patches, and we classify the patches using Sparse Representation-based Classification, respectively. At last, the identity of a test image can be determined by the classification results of its patches. Experimental results on the Yale B database and the CMU PIE database show that excellent recognition rates can be achieved by the proposed method.

  5. Adaptation of prey and predators between patches.

    PubMed

    Wang, Wendi; Takeuchi, Yasuhiro

    2009-06-21

    Mathematical models are proposed to simulate migrations of prey and predators between patches. In the absence of predators, it is shown that the adaptation of prey leads to an ideal spatial distribution in the sense that the maximal capacity of each patch is achieved. With the introduction of co-adaptation of predators, it is proved that both prey and predators achieve ideal spatial distributions when the adaptations are weak. Further, it is shown that the adaptation of prey and predators increases the survival probability of predators from the extinction in both patches to the persistence in one patch. It is also demonstrated that there exists a pattern that prey and predators cooperate well through adaptations such that predators are permanent in every patch in the case that predators become extinct in each patch in the absence of adaptations. For strong adaptations, it is proved that the model admits periodic cycles and multiple stability transitions.

  6. Slime moulds use heuristics based on within-patch experience to decide when to leave.

    PubMed

    Latty, Tanya; Beekman, Madeleine

    2015-04-15

    Animals foraging in patchy, non-renewing or slowly renewing environments must make decisions about how long to remain within a patch. Organisms can use heuristics ('rules of thumb') based on available information to decide when to leave the patch. Here, we investigated proximate patch-departure heuristics in two species of giant, brainless amoeba: the slime moulds Didymium bahiense and Physarum polycephalum. We explicitly tested the importance of information obtained through experience by eliminating chemosensory cues of patch quality. In P. polycephalum, patch departure was influenced by the consumption of high, and to a much lesser extent low, quality food items such that engulfing a food item increased patch-residency time. Physarum polycephalum also tended to forage for longer in darkened, 'safe' patches. In D. bahiense, engulfment of any food item increased patch residency irrespective of that food item's quality. Exposure to light had no effect on the patch-residency time of D. bahiense. Given that these organisms lack a brain, our results illustrate how the use of simple heuristics can give the impression that individuals make sophisticated foraging decisions.

  7. Scale-dependent feedbacks between patch size and plant reproduction in desert grassland

    USGS Publications Warehouse

    Svejcar, Lauren N.; Bestelmeyer, Brandon T.; Duniway, Michael C.; James, Darren K.

    2015-01-01

    Theoretical models suggest that scale-dependent feedbacks between plant reproductive success and plant patch size govern transitions from highly to sparsely vegetated states in drylands, yet there is scant empirical evidence for these mechanisms. Scale-dependent feedback models suggest that an optimal patch size exists for growth and reproduction of plants and that a threshold patch organization exists below which positive feedbacks between vegetation and resources can break down, leading to critical transitions. We examined the relationship between patch size and plant reproduction using an experiment in a Chihuahuan Desert grassland. We tested the hypothesis that reproductive effort and success of a dominant grass (Bouteloua eriopoda) would vary predictably with patch size. We found that focal plants in medium-sized patches featured higher rates of grass reproductive success than when plants occupied either large patch interiors or small patches. These patterns support the existence of scale-dependent feedbacks in Chihuahuan Desert grasslands and indicate an optimal patch size for reproductive effort and success in B. eriopoda. We discuss the implications of these results for detecting ecological thresholds in desert grasslands.

  8. Foil Patches Seal Small Vacuum Leaks

    NASA Technical Reports Server (NTRS)

    Spiegel, Kirk W.; Reed, David W.

    1995-01-01

    Report discloses technique to patch holes in nickel-alloy rocket-engine nozzle parts prior to vacuum brazing. Technique involves lightly spot-welding nickel foil 0.002 in. thick over hole patched, then spot-welding corrosion-resistant steel foil of same thickness over nickel foil. Once patches subject to pressure and temperature of vacuum brazing, nickel foil diffuses to bond with nickel-alloy nozzle, making vacuum-tight seal.

  9. Measurement and control of electrostatic patch potentials

    NASA Astrophysics Data System (ADS)

    Garrett, Joseph L.; Munday, Jeremy N.

    Electrostatic patch potentials hinder many precision measurements, particularly measurements of the Casimir force. Despite the improved force sensitivity achieved over the last decade, only recently have attempts been made to measure and quantify the effects of patch potentials. Here we present an analysis of patch potentials measured by Kelvin probe force microscopy (KPFM) and discuss methods to control these potentials (e.g. humidity, material choice, etc).

  10. Multi-Mode Broadband Patch Antenna

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R. (Inventor)

    2001-01-01

    A multi-mode broad band patch antenna is provided that allows for the same aperture to be used at independent frequencies such as reception at 19 GHz and transmission at 29 GHz. Furthermore, the multi-mode broadband patch antenna provides a ferroelectric film that allows for tuning capability of the multi-mode broadband patch antenna over a relatively large tuning range. The alternative use of a semiconductor substrate permits reduced control voltages since the semiconductor functions as a counter electrode.

  11. RF MEMS reconfigurable triangular patch antenna.

    SciTech Connect

    Nordquist, Christopher Daniel; Christodoulou, Christos George; Feldner, Lucas Matthew

    2005-01-01

    A Ka-band RF MEMS enabled frequency reconfigurable triangular microstrip patch antenna has been designed for monolithic integration with RF MEMS phase shifters to demonstrate a low-cost monolithic passive electronically scanned array (PESA). This paper introduces our first prototype reconfigurable triangular patch antenna currently in fabrication. The aperture coupled patch antenna is fabricated on a dual-layer quartz/alumina substrate using surface micromachining techniques.

  12. RF MEMS reconfigurable triangular patch antenna.

    SciTech Connect

    Christodoulou, Christos George; Nordquist, Christopher Daniel; Feldner, Lucas Matthew

    2005-07-01

    A Ka-band RF MEMS enabled frequency reconfigurable triangular microstrip patch antenna has been designed for monolithic integration with RF MEMS phase shifters to demonstrate a low-cost monolithic passive electronically scanned array (PESA). This paper introduces our first prototype reconfigurable triangular patch antenna currently in fabrication. The aperture coupled patch antenna is fabricated on a dual-layer quartz/alumina substrate using surface micromachining techniques.

  13. Patch definition in metapopulation analysis: a graph theory approach to solve the mega-patch problem.

    PubMed

    Cavanaugh, Kyle C; Siegel, David A; Raimondi, Peter T; Alberto, Filipe

    2014-02-01

    The manner in which patches are delineated in spatially realistic metapopulation models will influence the size, connectivity, and extinction and recolonization dynamics of those patches. Most commonly used patch-definition methods focus on identifying discrete, contiguous patches of habitat from a single temporal observation of species occurrence or from a model of habitat suitability. However, these approaches are not suitable for many metapopulation systems where entire patches may not be fully colonized at a given time. For these metapopulation systems, a single large patch of habitat may actually support multiple, interacting subpopulations. The interactions among these subpopulations will be ignored if the patch is treated as a single unit, a situation we term the "mega-patch problem." Mega-patches are characterized by variable intra-patch synchrony, artificially low inter-patch connectivity, and low extinction rates. One way to detect this problem is by using time series data to calculate demographic synchrony within mega-patches. We present a framework for identifying subpopulations in mega-patches using a combination of spatial autocorrelation and graph theory analyses. We apply our approach to southern California giant kelp (Macrocystis pyrifera) forests using a new, long-term (27 years), satellite-based data set of giant kelp canopy biomass. We define metapopulation patches using our method as well as several other commonly used patch delineation methodologies and examine the colonization and extinction dynamics of the metapopulation under each approach. We find that the relationships between patch characteristics such as area and connectivity and the demographic processes of colonizations and extinctions vary among the different patch-definition methods. Our spatial-analysis/graph-theoretic framework produces results that match theoretical expectations better than the other methods. This approach can be used to identify subpopulations in metapopulations

  14. Collection of analytes from microneedle patches.

    PubMed

    Romanyuk, Andrey V; Zvezdin, Vasiliy N; Samant, Pradnya; Grenader, Mark I; Zemlyanova, Marina; Prausnitz, Mark R

    2014-11-04

    Clinical medicine and public health would benefit from simplified acquisition of biological samples from patients that can be easily obtained at point of care, in the field, and by patients themselves. Microneedle patches are designed to serve this need by collecting dermal interstitial fluid containing biomarkers without the dangers, pain, or expertise needed to collect blood. This study presents novel methods to collect biomarker analytes from microneedle patches for analysis by integration into conventional analytical laboratory microtubes and microplates. Microneedle patches were made out of cross-linked hydrogel composed of poly(methyl vinyl ether-alt-maleic acid) and poly(ethylene glycol) prepared by micromolding. Microneedle patches were shown to swell with water up to 50-fold in volume, depending on degree of polymer cross-linking, and to collect interstitial fluid from the skin of rats. To collect analytes from microneedle patches, the patches were mounted within the cap of microcentrifuge tubes or formed the top of V-bottom multiwell microplates, and fluid was collected in the bottom of the tubes under gentle centrifugation. In another method, microneedle patches were attached to form the bottom of multiwell microplates, thereby enabling in situ analysis. The simplicity of biological sample acquisition using microneedle patches coupled with the simplicity of analyte collection from microneedles patches integrated into conventional analytical equipment could broaden the reach of future screening, diagnosis, and monitoring of biomarkers in healthcare and environmental/workplace settings.

  15. Two Holes in 'Wooly Patch'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The rock abrasion tool on NASA's Mars Exploration Rover Spirit ground two holes in a relatively soft rock called 'Wooly Patch' near the base of the 'Columbia Hills' inside Gusev Crater on Mars. This approximately true-color image from the panoramic camera was taken on sol 200 (July 25, 2004) and generated using the camera's 600-, 530-, and 480-nanometer filters. It shows the natural red and reddish-brown color of the rock. Scientists speculate that this relatively soft rock (compared to others analyzed by Spirit) may have been modified by water. Small cracks in the surface outside the drill holes may be the result of interactions with water-rich fluids.

  16. HotPatch Web Gateway: Statistical Analysis of Unusual Patches on Protein Surfaces

    DOE Data Explorer

    Pettit, Frank K.; Bowie, James U. [DOE-Molecular Biology Institute

    HotPatch finds unusual patches on the surface of proteins, and computes just how unusual they are (patch rareness), and how likely each patch is to be of functional importance (functional confidence (FC).) The statistical analysis is done by comparing your protein's surface against the surfaces of a large set of proteins whose functional sites are known. Optionally, HotPatch can also write a script that will display the patches on the structure, when the script is loaded into some common molecular visualization programs. HotPatch generates complete statistics (functional confidence and patch rareness) on the most significant patches on your protein. For each property you choose to analyze, you'll receive an email to which will be attached a PDB-format file in which atomic B-factors (temp. factors) are replaced by patch indices; and the PDB file's Header Remarks will give statistical scores and a PDB-format file in which atomic B-factors are replaced by the raw values of the property used for patch analysis (for example, hydrophobicity instead of hydrophobic patches). [Copied with edits from http://hotpatch.mbi.ucla.edu/

  17. Transdermal patches: history, development and pharmacology

    PubMed Central

    Pastore, Michael N; Kalia, Yogeshvar N; Horstmann, Michael; Roberts, Michael S

    2015-01-01

    Transdermal patches are now widely used as cosmetic, topical and transdermal delivery systems. These patches represent a key outcome from the growth in skin science, technology and expertise developed through trial and error, clinical observation and evidence-based studies that date back to the first existing human records. This review begins with the earliest topical therapies and traces topical delivery to the present-day transdermal patches, describing along the way the initial trials, devices and drug delivery systems that underpin current transdermal patches and their actives. This is followed by consideration of the evolution in the various patch designs and their limitations as well as requirements for actives to be used for transdermal delivery. The properties of and issues associated with the use of currently marketed products, such as variability, safety and regulatory aspects, are then described. The review concludes by examining future prospects for transdermal patches and drug delivery systems, such as the combination of active delivery systems with patches, minimally invasive microneedle patches and cutaneous solutions, including metered-dose systems. PMID:25560046

  18. Immunoisolation Patch System for Cellular Transplantation

    NASA Technical Reports Server (NTRS)

    Wang, Taylor G. (Inventor)

    2014-01-01

    An immunoisolation patch system, and particularly a patch system comprising multiple immunoisolation microcapsules, each encapsulating biological material such as cells for transplantation, which can be used in the prophylactic and therapeutic treatment of disease in large animals and humans without the need for immunosuppression.

  19. Formulation study of tea tree oil patches.

    PubMed

    Minghetti, Paola; Casiraghi, Antonella; Cilurzo, Francesco; Gambaro, Veniero; Montanari, Luisa

    2009-01-01

    The antimicrobial, antifungal and anti-inflammatory properties of tea tree oil (TTO), the essential oil of Melaleuca alternifolia are well documented. In order to optimize its therapeutic activity, TTO patches were designed. The aim of this work was the formulation of monolayer patches containing TTO. Moreover, the performance of oleic acid (OA) as a skin penetration enhancer in patches was evaluated. Terpinen-4-ol (T4OL), the main component of TTO, was the marker used to evaluate TTO skin permeability. The permeation study was performed through human epidermis by using Franz diffusion cells. Patches were prepared by using methacrylic copolymers, Eudragit E100 (EuE100) or Eudragit NE (EuNE), and a silicone resin, BioPSA7-4602 (Bio-PSA). TTO and OA contents were fixed at 10% w/w and 3% w/w, respectively. The patches were prepared by a casting method and characterised in terms of T4OL content and skin permeability. All the selected polymers were suitable as the main component of the patch matrix. Since the main critical issue in the use of TTO is related to its toxicity after absorption, the local administration of TTO can take advantage of the use of patches based on EuE100 because of the high retained amount and the low permeation of T4OL. In this matrix, OA slightly increased the T4OL retained amount, improving the efficacy and safety of TTO patches.

  20. Patch scales in coastal ecosystems

    NASA Astrophysics Data System (ADS)

    Broitman, Bernardo R.

    Quantifying the spatial and temporal scales over which ecological processes are coupled to environmental variability is a major challenge for ecologists. Here, I assimilate patterns of oceanographic variability with ecological field studies in an attempt to quantify spatial and temporal scales of coupling. Using coastal time series of chlorophyll-a concentration from remote sensing, the first chapter examines the alongshore extent of coastal regions subject to similar temporal patterns of oceanographic variability in Western North America (WNA) and North-Central Chile (Chile). I found striking interhemispherical differences in the length of coastal sections under similar oceanographic regimes, with the Chile region showing longshore coherency over much smaller spatial scales (˜60 km) than on the coast of WNA (˜140 km). Through a spatial analysis of coastal orientation I suggest that the characteristic length scales may be traced to the geomorphologic character of the ocean margins. The second chapter examines spatial patterns of primary production through long-term means of coastal chlorophyll-a concentration and kelp (Macrocystis pyrifera) cover and explores their relationship with coastal geomorphology and sea surface temperature (SST). Spatial analyses showed a striking match in length scales around 180--250 km. Strong anticorrelations at small spatial lags and positive correlations at longer distances suggest little overlap between patches of kelp and coastal chlorophyll-a. In agreement with findings from the previous chapter, I found that coastal patches could be traced back to spatial patterns of coastal geomorphology. Through SST time series and long-term datasets of larval recruitment in Santa Cruz Island, California, the third chapter examines temporal patterns of oceanographic variability as determinants of ecological patterns. SST time series from sites experiencing low larval recruitment rates were dominated by strong temporal variability. These sites

  1. Image Quality Assessment Based on Inter-Patch and Intra-Patch Similarity

    PubMed Central

    Zhou, Fei; Lu, Zongqing; Wang, Can; Sun, Wen; Xia, Shu-Tao; Liao, Qingmin

    2015-01-01

    In this paper, we propose a full-reference (FR) image quality assessment (IQA) scheme, which evaluates image fidelity from two aspects: the inter-patch similarity and the intra-patch similarity. The scheme is performed in a patch-wise fashion so that a quality map can be obtained. On one hand, we investigate the disparity between one image patch and its adjacent ones. This disparity is visually described by an inter-patch feature, where the hybrid effect of luminance masking and contrast masking is taken into account. The inter-patch similarity is further measured by modifying the normalized correlation coefficient (NCC). On the other hand, we also attach importance to the impact of image contents within one patch on the IQA problem. For the intra-patch feature, we consider image curvature as an important complement of image gradient. According to local image contents, the intra-patch similarity is measured by adaptively comparing image curvature and gradient. Besides, a nonlinear integration of the inter-patch and intra-patch similarity is presented to obtain an overall score of image quality. The experiments conducted on six publicly available image databases show that our scheme achieves better performance in comparison with several state-of-the-art schemes. PMID:25793282

  2. Reconfigurable Wideband Circularly Polarized Microstrip Patch Antenna for Wireless Applications

    NASA Astrophysics Data System (ADS)

    Khidre, Ahmed

    vice versa, with the aid of two RF PIN diodes that act as RF switches. The proposed structure which is simple; consists of a single-layer single fed radiating E-shaped patch and RF switch placed on each of its slots at an appropriate location. The design targets WLAN IEEE 802.11b/g frequency band (2.4- 2.5 GHz) as one example of the wireless applications. The idea is based on the first proposed design. In other words, if one of the switches is ON and the other is OFF, the two slot lengths will become effectively unequal and circular polarization will be obtained. If the states of the two switches are reversed, circular polarization with opposite orientation will be obtained at the same frequency band. Full-wave simulator Ansoft HFSS is again used for the analysis. Complete detailed DC biasing circuit of the switches for integration with the antenna is presented. Also, characterizations of the microwave components used in the biasing circuit are discussed. Antenna prototype has been fabricated and tested. Simulation results along with the measured one, for the reflection coefficient, axial ratio, radiation pattern, and antenna gain agree well, showing wide bandwidth and high gain for the two circularly polarized modes.

  3. A case of secondary syphilis with mucous patches on the hard palate.

    PubMed

    Ban, M; Ohtani, M; Seishima, M

    1995-01-01

    A rare case of secondary syphilis showing mucous patches on the hard palate is reported. A 31-year-old male had two erosive patches which were slightly raised on his hard palate. A linear lesion was also present on the inside of his right alveolar process. Many red-brown macules on his abdomen and bilateral inguinal lymphadenopathy accompanied these symptoms. The serological tests for syphilis were positive: VDRL test 1:512, TPHA test 1:20,480, and IgM-FTA-ABS test 1:40. Immunohistochemical staining with rabbit monoclonal antibody to Treponema pallidum by the biotin-streptoavidin system detected treponemal organisms in the paraffin-embedded specimen from his mucous patch. A diagnosis of secondary syphilis was made, and he was given amoxicillin (AMPC) at 750 mg per day for 4 weeks. His eruptions, including the mucous patch, healed in a week.

  4. Evaluation of a mucoadhesive buccal patch for delivery of peptides: in vitro screening of bioadhesion.

    PubMed

    Li, C; Bhatt, P P; Johnston, T P

    1998-10-01

    We have assessed the bioadhesive properties of several different mucoadhesive buccal patches. The patches consisted of custom coformulations of silicone polymers and Carbopol 974P. The contact angle of water was measured for each of the test formulations, using an ophthalmic shadow scope. The corresponding work of adhesion between the water and the patches (W1), and between the patches and freshly-excised rabbit buccal mucosa (W2) was then calculated, using a modification of Dupre's equation. The bioadhesive strength between the patches and excised rabbit buccal mucosa was also assessed. The results of the contact-angle measurements indicated that the contact angle decreased with an increase in the amount of Carbopol in the formulation. Additionally, the calculated values of both W1 and W2 increased with an increase in the amount of Carbopol in the buccal-patch formulations. A correlation (r not equal to 0.9808) was found between the measured contact angle and the calculated values for W2. The direct measurement of the force required to separate a buccal patch from excised rabbit buccal mucosa with the INSTRON demonstrated that the adhesive strength increased with an increase in the amount of Carbopol. This preliminary study has shown that the measurement of contact angles alone may provide a useful technique for estimating the work of adhesion, and may serve as a convenient and rapid screening procedure to identify potential mucoadhesive buccal-patch formulations.

  5. Pairwise Operator Learning for Patch Based Single-image Super-resolution.

    PubMed

    Tang, Yi; Shao, Ling

    2016-12-14

    Motivated by the fact that image patches could be inherently represented by matrices, single-image super-resolution is treated as a problem of learning regression operators in a matrix space in this paper. The regression operators that map low-resolution image patches to high-resolution image patches are generally defined by left and right multiplication operators. The pairwise operators are respectively used to extract the raw and column information of low-resolution image patches for recovering high-resolution estimations. The patch based regression algorithm possesses three favorable properties. Firstly, the proposed super-resolution algorithm is efficient during both training and testing, because image patches are treated as matrices. Secondly, the data storage requirement of the optimal pairwise operator is far less than most popular single-image super-resolution algorithms because only two small sized matrices need to be stored. Lastly, the super-resolution performance is competitive with most popular single-image super-resolution algorithms because both raw and column information of image patches is considered. Experimental results show the efficiency and effectiveness of the proposed patch-based single-image superresolution algorithm.

  6. Relative abundance of mesopredators and size of oak patches in the cross-timbers ecoregion

    USGS Publications Warehouse

    Disney, M.R.; Hellgren, E.C.; Davis, C.A.; Leslie, David M.; Engle, David M.

    2008-01-01

    Mesopredators (e.g., raccoon Procyon lotor, Virginia opossum Didelphis virginiana, striped skunk Mephitis mephitis) have received considerable attention because of links to population declines in birds via increased nest predation, especially in landscapes fragmented by anthropogenic forces. Relationships of abundance of mesopredators to size of habitat patches have received less attention than relationships to other metrics of fragmentation, particularly edge characteristics. We tested the hypothesis that relative abundance of mesopredators (e.g., raccoons and Virginia opossums) was related negatively to size of forest patch. We delineated 15 patches of oak (Quercus) forest ranging from 0.2 to 55.3 ha within a grassland-woodland mosaic in the cross-timbers ecoregion of Oklahoma. Scent stations and live traps within these patches were used to index relative abundance of mesopredators in summers 2003 and 2004. Both indices of relative abundance were related weakly and negatively to area of forest patch. However, rate of capture and visitation to scent station were not correlated consistently throughout the study. Our results suggested that the two methods to index abundance provided separate information on functional and numerical responses to size of patch. Our evidence that mesopredators within the cross timbers were more likely to be in smaller patches of oak forest may have implications to success of avian nesting in these patches.

  7. A procedure of landscape services assessment based on mosaics of patches and boundaries.

    PubMed

    Martín de Agar, Pilar; Ortega, Marta; de Pablo, Carlos L

    2016-09-15

    We develop a procedure for assessing the environmental value of landscape mosaics that simultaneously considers the values of land use patches and the values of the boundaries between them. These boundaries indicate the ecological interactions between the patches. A landscape mosaic is defined as a set of patches and the boundaries between them and corresponds to a spatial pattern of ecological interactions. The procedure is performed in two steps: (i) an environmental assessment of land use patches by means of a function that integrates values based on the goods and services the patches provide, and (ii) an environmental valuation of mosaics using a function that integrates the environmental values of their patches and the types and frequencies of the boundaries between them. This procedure allows us to measure how changes in land uses or in their spatial arrangement cause variations in the environmental value of landscape mosaics and therefore in that of the whole landscape. The procedure was tested in the Sierra Norte of Madrid (central Spain). The results show that the environmental values of the landscape depend not only on the land use patches but also on the values associated with the pattern of the boundaries within the mosaics. The results also highlight the importance of the boundaries between land use patches as determinants of the goods and services provided by the landscape.

  8. Effects of Spatial Patch Arrangement and Scale of Covarying Resources on Growth and Intraspecific Competition of a Clonal Plant

    PubMed Central

    Wang, Yong-Jian; Shi, Xue-Ping; Meng, Xue-Feng; Wu, Xiao-Jing; Luo, Fang-Li; Yu, Fei-Hai

    2016-01-01

    Spatial heterogeneity in two co-variable resources such as light and water availability is common and can affect the growth of clonal plants. Several studies have tested effects of spatial heterogeneity in the supply of a single resource on competitive interactions of plants, but none has examined those of heterogeneous distribution of two co-variable resources. In a greenhouse experiment, we grew one (without intraspecific competition) or nine isolated ramets (with competition) of a rhizomatous herb Iris japonica under a homogeneous environment and four heterogeneous environments differing in patch arrangement (reciprocal and parallel patchiness of light and soil water) and patch scale (large and small patches of light and water). Intraspecific competition significantly decreased the growth of I. japonica, but at the whole container level there were no significant interaction effects of competition by spatial heterogeneity or significant effect of heterogeneity on competitive intensity. Irrespective of competition, the growth of I. japonica in the high and the low water patches did not differ significantly in the homogeneous treatments, but it was significantly larger in the high than in the low water patches in the heterogeneous treatments with large patches. For the heterogeneous treatments with small patches, the growth of I. japonica was significantly larger in the high than in the low water patches in the presence of competition, but such an effect was not significant in the absence of competition. Furthermore, patch arrangement and patch scale significantly affected competitive intensity at the patch level. Therefore, spatial heterogeneity in light and water supply can alter intraspecific competition at the patch level and such effects depend on patch arrangement and patch scale. PMID:27375630

  9. Group-Living Herbivores Weigh Up Food Availability and Dominance Status when Making Patch-Joining Decisions

    PubMed Central

    Stears, Keenan; Kerley, Graham I. H.; Shrader, Adrian M.

    2014-01-01

    Two key factors that influence the foraging behaviour of group-living herbivores are food availability and individual dominance status. Yet, how the combination of these factors influences the patch-joining decisions of individuals foraging within groups has scarcely been explored. To address this, we focused on the patch-joining decisions of group-living domestic goats (Capra hircus). When individuals were tested against the top four ranked goats of the herd, we found that at patches with low food availability they avoided these dominant patch-holders and only joined subordinates (i.e. costs outweighed benefits). However, as the amount of food increased, the avoidance of the top ranked individuals declined. Specifically, goats shifted and joined the patch of an individual one dominance rank higher than the previous dominant patch holder when the initial quantity of food in the new patch was twice that of the lower ranking individual’s patch (i.e. benefits outweighed costs). In contrast, when individuals chose between patches held by dominant goats, other than the top four ranked goats, and subordinate individuals, we found that they equally joined the dominant and subordinate patch-holders. This joining was irrespective of the dominance gap, absolute rank of the dominant patch-holder, sex or food availability (i.e. benefits outweighed costs). Ultimately, our results highlight that herbivores weigh up the costs and benefits of both food availability and patch-holder dominance status when making patch-joining decisions. Furthermore, as the initial quantity of food increases, food availability becomes more important than dominance with regard to influencing patch-joining decisions. PMID:25271889

  10. Effects of Spatial Patch Arrangement and Scale of Covarying Resources on Growth and Intraspecific Competition of a Clonal Plant.

    PubMed

    Wang, Yong-Jian; Shi, Xue-Ping; Meng, Xue-Feng; Wu, Xiao-Jing; Luo, Fang-Li; Yu, Fei-Hai

    2016-01-01

    Spatial heterogeneity in two co-variable resources such as light and water availability is common and can affect the growth of clonal plants. Several studies have tested effects of spatial heterogeneity in the supply of a single resource on competitive interactions of plants, but none has examined those of heterogeneous distribution of two co-variable resources. In a greenhouse experiment, we grew one (without intraspecific competition) or nine isolated ramets (with competition) of a rhizomatous herb Iris japonica under a homogeneous environment and four heterogeneous environments differing in patch arrangement (reciprocal and parallel patchiness of light and soil water) and patch scale (large and small patches of light and water). Intraspecific competition significantly decreased the growth of I. japonica, but at the whole container level there were no significant interaction effects of competition by spatial heterogeneity or significant effect of heterogeneity on competitive intensity. Irrespective of competition, the growth of I. japonica in the high and the low water patches did not differ significantly in the homogeneous treatments, but it was significantly larger in the high than in the low water patches in the heterogeneous treatments with large patches. For the heterogeneous treatments with small patches, the growth of I. japonica was significantly larger in the high than in the low water patches in the presence of competition, but such an effect was not significant in the absence of competition. Furthermore, patch arrangement and patch scale significantly affected competitive intensity at the patch level. Therefore, spatial heterogeneity in light and water supply can alter intraspecific competition at the patch level and such effects depend on patch arrangement and patch scale.

  11. Patch shape, connectivity, and foraging by oldfield mice (Peromyscus polionotus).

    SciTech Connect

    Orrock, John, L.; Danielson, Brent J

    2005-06-01

    We examined how corridors and patch shape affect foraging by the oldfield mouse (Peromyscus polionotus) by deploying foraging trays and live traps in experimental landscapes with 3 different patch types: patches connected with a corridor, unconnected patches with projecting corridorlike portions (winged patches), and unconnected rectangular patches. Corridors did not lead to different levels of activity of P. polionotus among the 3 patch types. Rather, corridors influenced activity by changing patch shape: foraging in seed trays and total number of captures of P. polionotus tended to be greater at the patch center than at the patch edge, but only in connected and winged patches where corridors or wings increased the amount of patch edge relative to the amount of core habitat in the patch. P. polionotus avoided open microhabitats near the patch edge in winged and connected patches, but not open microhabitats near the patch interior, suggesting that predation risk caused shifts in foraging near edges in connected and winged patches. Foraging in corridors and wings was generally low, suggesting that both are high-risk habitats where predation risk is not ameliorated by proximity to vegetative cover. By changing patch shape, corridors caused changes in within-patch activity of P. polionotus, changing foraging patterns and potentially altering the dynamics of P. polionotus and the seeds they consume.

  12. Electrostatic patch potentials in Casimir force measurements

    NASA Astrophysics Data System (ADS)

    Garrett, Joseph; Somers, David; Munday, Jeremy

    2015-03-01

    Measurements of the Casimir force require the elimination of the electrostatic force between interacting surfaces. The force can be minimized by applying a potential to one of the two surfaces. However, electrostatic patch potentials remain and contribute an additional force which can obscure the Casimir force signal. We will discuss recent measurements of patch potentials made with Heterodyne Amplitude-Modulated Kelvin Probe Force Microscopy that suggest patches could be responsible for >1% of the signal in some Casimir force measurements, and thus make the distinction between different theoretical models of the Casimir force (e.g. a Drude-model or a plasma-model for the dielectric response) difficult to discern.

  13. Scattering from arbitrarily shaped microstrip patch antennas

    NASA Technical Reports Server (NTRS)

    Shively, David G.; Deshpande, Manohar D.; Cockrell, Capers R.

    1992-01-01

    The scattering properties of arbitrarily shaped microstrip patch antennas are examined. The electric field integral equation for a current element on a grounded dielectric slab is developed for a rectangular geometry based on Galerkin's technique with subdomain rooftop basis functions. A shape function is introduced that allows a rectangular grid approximation to the arbitrarily shaped patch. The incident field on the patch is expressed as a function of incidence angle theta(i), phi(i). The resulting system of equations is then solved for the unknown current modes on the patch, and the electromagnetic scattering is calculated for a given angle. Comparisons are made with other calculated results as well as with measurements.

  14. Can Stem Cell 'Patch' Help Heart Failure?

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_164475.html Can Stem Cell 'Patch' Help Heart Failure? Small improvement seen over ... Scientists report another step in the use of stem cells to help treat people with debilitating heart failure. ...

  15. The Smart Patches and Wearable Band (W-Band) for comfortable sleep monitoring system.

    PubMed

    Lee, Seulki; Yan, Long; Roh, Taehwan; Hong, Sunjoo; Yoo, Hoi-Jun

    2011-01-01

    The Smart Patches and Wearable Band (W-Band) are proposed for comfortable sleep monitoring system which recognizes and diagnoses sleep disorders. By using Planar Fashionable Circuit Board (P-FCB) techniques, the Smart Patches are implemented with the plain fabric patch so that it can have light weight and small size. And the stretchability of the W-Band can achieve user convenience, low manufacturing cost, and low power consumption all at once. The data display program is developed on the external PC so that the user can check the monitoring result after wake-up. The proposed sleep monitoring system is fully implemented and tested on the human during normal sleep.

  16. Structural Health Monitoring of a Bonded Composite Patch Repair on a Fatigue-Cracked F-111C Wing

    DTIC Science & Technology

    2008-03-01

    fractographic observations just prior to failure of the wing in the fatigue test . For the patch system, based on the use of the bond-strength test as a...Environmental degradation of the adhesive bond would be manifested in the test as low strength and failure at the aluminium alloy surface - termed adhesive...34: Patch segments showing the bond test results. The location of the bond test plugs are shown together with the bond strength in MPa and failure

  17. Management of prosthetic patch infection after CEA.

    PubMed

    Naylor, Ross

    2016-04-01

    It has been reported that 0.5-1% of patients undergoing carotid endarterectomy with prosthetic patch closure of the arteriotomy will develop patch infection. One third occur within the first 2 months after surgery, while two-thirds occur after >6 months have elapsed. Wound infection and abscess formation is the commonest mode of presentation in early cases, while chronic sinus discharge and false aneurysm formation are the commonest presentations in late cases. The commonest infecting organisms are Staphylococci/Streptococci (90%) and this should be borne in mind when planning antibiotic therapy before cultures are available. Most patch infections present (semi)-electively and patch rupture is relatively rare (10%), thereby enabling the surgeon to undertake careful evaluation of the patients overall clinical and anatomical status, whilst planning the optimal treatment strategy. If necessary, the patient should be transferred to a tertiary center for treatment. This is not an operation to be undertaken by an inexperienced surgeon. Operative planning should involve checking the original operation note (did the patient tolerate carotid clamping under locoregional anesthesia and therefore might tolerate carotid ligation), is there evidence of contralateral cranial nerve lesions (a contraindication to major open surgery) and has the surgeon planned for adequate distal exposure of the internal carotid artery. Patch excision and autologous reconstruction (usually vein) is the current 'gold standard' treatment, but highly selected patients can be successfully treated by less invasive surgery (including insertion of a covered stent). Patch excision and prosthetic reconstruction should be avoided.

  18. Patch-clamp amplifiers on a chip.

    PubMed

    Weerakoon, Pujitha; Culurciello, Eugenio; Yang, Youshan; Santos-Sacchi, Joseph; Kindlmann, Peter J; Sigworth, Fred J

    2010-10-15

    We present the first, fully integrated, two-channel implementation of a patch-clamp measurement system. With this "PatchChip" two simultaneous whole-cell recordings can be obtained with rms noise of 8pA in a 10kHz bandwidth. The capacitance and series-resistance of the electrode can be compensated up to 10pF and 100MΩ respectively under computer control. Recordings of hERG and Na(v) 1.7 currents demonstrate the system's capabilities, which are on par with large, commercial patch-clamp instrumentation. By reducing patch-clamp amplifiers to a millimeter size micro-chip, this work paves the way to the realization of massively parallel, high-throughput patch-clamp systems for drug screening and ion-channel research. The PatchChip is implemented in a 0.5μm silicon-on-sapphire process; its size is 3×3mm(2) and the power consumption is 5mW per channel with a 3.3V power supply.

  19. Preparation of Mucoadhesive Oral Patches Containing Tetracycline Hydrochloride and Carvacrol for Treatment of Local Mouth Bacterial Infections and Candidiasis

    PubMed Central

    Obaidat, Rana M.; Bader, Ammar; Al-Rajab, Wafa; Abu Sheikha, Ghassan; Obaidat, Aiman A.

    2011-01-01

    The specific aim of this work was to prepare mucoadhesive patches containing tetracycline hydrochloride and carvacrol in an attempt to develop a novel oral drug delivery system for the treatment of mouth infections. The bilayered patches were prepared using ethyl cellulose as a backing layer and carbopol 934 as a matrix mucoadhesive layer. Patches were prepared with different loading amounts of tetracycline hydrochloride and carvacrol. The antimicrobial activity was assessed for the prepared patches using the disc-diffusion method against the yeast Candida albicans and five bacterial strains, including Pseudomonas aeruginosa, Escherichia coli, Bacillus cereus, Staphylococcus aureus, and Bacillus bronchispti. In this work, we highlighted the possibility of occurrence of a synergistic action between carvacrol and tetracycline. The best formulation was selected based on microbiological tests, drug release, ex-vivo mucoadhesive performance, and swelling index. Physical characteristics of the selected formulations were determined. These included pH, patch thickness, weight uniformity, content uniformity, folding endurance, and patch stability. PMID:21617783

  20. Short-term monocular patching boosts the patched eye’s response in visual cortex

    PubMed Central

    Zhou, Jiawei; Baker, Daniel H.; Simard, Mathieu; Saint-Amour, Dave; Hess, Robert F.

    2015-01-01

    Abstract Purpose: Several recent studies have demonstrated that following short-term monocular deprivation in normal adults, the patched eye, rather than the unpatched eye, becomes stronger in subsequent binocular viewing. However, little is known about the site and nature of the underlying processes. In this study, we examine the underlying mechanisms by measuring steady-state visual evoked potentials (SSVEPs) as an index of the neural contrast response in early visual areas. Methods: The experiment consisted of three consecutive stages: a pre-patching EEG recording (14 minutes), a monocular patching stage (2.5 hours) and a post-patching EEG recording (14 minutes; started immediately after the removal of the patch). During the patching stage, a diffuser (transmits light but not pattern) was placed in front of one randomly selected eye. During the EEG recording stage, contrast response functions for each eye were measured. Results: The neural responses from the patched eye increased after the removal of the patch, whilst the responses from the unpatched eye remained the same. Such phenomena occurred under both monocular and dichoptic viewing conditions. Conclusions: We interpret this eye dominance plasticity in adult human visual cortex as homeostatic intrinsic plasticity regulated by an increase of contrast-gain in the patched eye. PMID:26410580

  1. The effects of patch shape and connectivity on nest site selection and reproductive success of the Indigo Bunting.

    SciTech Connect

    Weldon, Aimee Jean

    2004-07-01

    Description – Ph.D Dissertation. North Carolina State University. Raleigh, North Carolina. 135 pp. Abatract - Habitat fragmentation and its associated effects have been blamed for the recent population declines of many Neotropical migratory bird species. Increased predation and parasitism resulting from edge-related effects have been implicated for poor nesting success in many studies, mostly of forest interior species. However, little attention has been devoted to disturbance-dependent birds. In this study, I examine how patch shape and connectivity in fragmented landscapes affects the reproductive success of disturbance-dependent bird species, specifically the Indigo Bunting (Passerina cyanea). I conducted my study in a landscape-scale experimental system of similar-area habitat patches that differed in connectivity and in shape. Shapes differed between edgy and rectangular forms, where edgy patches contained 50% more edge than rectangular patches. I tested whether edgy patches function as ecological traps for species with strong edge preferences, by leading them to select dangerous habitats. Indigo Buntings preferentially selected edgy patches over rectangular patches, but experienced significantly lower reproductive success in edgy patches early in the season. Although predation pressure intensified in rectangular patches late in the season, seasonal fecundity was still significantly lower in edgy patches, providing the first empirical evidence that edges can function as ecological traps for Indigo Buntings. A second objective of my study was to evaluate the efficacy of conservation corridors for disturbance-dependent bird species. Conservation corridors have become a popular strategy to preserve biodiversity and promote gene flow in fragmented landscapes, but corridors may also have negative consequences. I tested the hypothesis that corridors can increase nest predation risk in connected patches relative to unconnected patches. Nest predation rates

  2. Effects of an emergent vegetation patch on channel reach bathymetry and stability during repeated unsteady flows

    NASA Astrophysics Data System (ADS)

    Waters, Kevin A.; Crowe Curran, Joanna

    2016-11-01

    While research into the interaction between in-channel vegetation, flow, and bed sediment has increased in recent years, there is still a need to understand how unsteady flows affect these processes, particularly in terms of channel bed adjustments. In this study, flume experiments tested two flood hydrograph sizes run over sand/gravel and sand/silt beds to evaluate reach scale impacts of a midchannel vegetation patch of variable stem density on channel bathymetry and stability. Alternating flood hydrographs with periods of low, steady flow created flow sequences reflective of an extended unsteady flow regime, thereby simulating time scales consisting of multiple flood events. Digital elevation models provided detailed measurements of channel change following each flood event to enable analysis over each unsteady flow sequence. The vegetation patch created characteristic channel bathymetries dependent on sediment mixture and patch density that in all cases resulted in a more variable bed structure than channels without a patch. Reach scale stability, quantified based on net volumetric bed change, only occurred with a sparse patch in the low flood sequence, corresponding with little variation in surface composition and structure. In most other cases, scour measured at the patch prevented stability at the reach scale, especially in the finer substrate. Overall, findings show that a channel may only adjust to a stable bathymetry upon addition of a midchannel vegetation patch within a limited range of flow regimes and patch stem densities, and that for the experimental conditions tested here, in-stream patches generally did not enhance reach scale bed stability.

  3. Truncated stacked elliptical patch antenna for broadband performance

    NASA Astrophysics Data System (ADS)

    Sharma, Vijay; Sharma, Brajraj; Sharma, K. B.; Bhatnagar, D.

    2013-01-01

    A new design of a single-feed truncated elliptical patch antenna with and without slots for broadband performance with stacked arrangement is proposed in this paper and its performance is tested in free space. This multilayered rectangular microstrip antenna is designed and analyzed by using the ie3d simulation software. In between conducting and ground plane, designed antenna has two glass epoxy fr-4 substrates separated by an air substrate to attain broadband performance. The impedance bandwidth of designed antenna is better than 2.11GHz or 60% with respect to the central frequency. The simulated e plane co and cross radiation patterns are identical in shape for most of the part of bandwidth however at higher frequency side due to the presence of higher modes and cross polarization the radiation pattern are no more directive normal to patch geometry.

  4. Dredging displaces bottlenose dolphins from an urbanised foraging patch.

    PubMed

    Pirotta, Enrico; Laesser, Barbara Eva; Hardaker, Andrea; Riddoch, Nicholas; Marcoux, Marianne; Lusseau, David

    2013-09-15

    The exponential growth of the human population and its increasing industrial development often involve large scale modifications of the environment. In the marine context, coastal urbanisation and harbour expansion to accommodate the rising levels of shipping and offshore energy exploitation require dredging to modify the shoreline and sea floor. While the consequences of dredging on invertebrates and fish are relatively well documented, no study has robustly tested the effects on large marine vertebrates. We monitored the attendance of common bottlenose dolphins (Tursiops truncatus) to a recently established urbanised foraging patch, Aberdeen harbour (Scotland), and modelled the effect of dredging operations on site usage. We found that higher intensities of dredging caused the dolphins to spend less time in the harbour, despite high baseline levels of disturbance and the importance of the area as a foraging patch.

  5. Mental confusion associated with scopolamine patch in elderly with mild cognitive impairment (MCI).

    PubMed

    Seo, Sang Won; Suh, Mee Kyung; Chin, Juhee; Na, Duk L

    2009-01-01

    Mental confusion or delirium can occur after application of scopolamine patch. However, predisposing factors for scopolamine-induced delirium are not known. It is expected that undetected incipient dementia or mild cognitive impairment (MCI) may be prone to develop mental confusion after applying the scopolamine patch. For the past 5 years, we found seven elderly women who had experienced transdermal scopolamine-induced mental confusion. They underwent neuropsychological tests after recovery from mental confusion (mean duration from onset to the test: 66 days). The results showed that all the patients were impaired in at least one of cognitive domains, fulfilling the criteria of MCI. These findings suggest that scopolamine patch-induced mental confusion should be included in the differential diagnoses of mental confusion in elderly, especially in travel situation, and that older people with undetected MCI are prone to develop scopolamine patch-induced mental confusion.

  6. Measuring Radiation Patterns of Reconfigurable Patch Antennas on Wafers

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.

    2004-01-01

    An apparatus and technique have been devised for measuring the radiation pattern of a microwave patch antenna that is one of a number of identical units that have been fabricated in a planar array on a high-resistivity silicon wafer. The apparatus and technique are intended, more specifically, for application to such an antenna that includes a DC-controlled microelectromechanical system (MEMS) actuator for switching the antenna between two polarization states or between two resonance frequencies. Prior to the development of the present apparatus and technique, patch antennas on wafers were tested by techniques and equipment that are more suited to testing of conventional printed-circuit antennas. The techniques included sawing of the wafers to isolate individual antennas for testing. The equipment included custom-built test fixtures that included special signal launchers and transmission-line transitions. The present apparatus and technique eliminate the need for sawing wafers and for custom-built test fixtures, thereby making it possible to test antennas in less time and at less cost. Moreover, in a production setting, elimination of the premature sawing of wafers for testing reduces loss from breakage, thereby enhancing yield.

  7. Individual colour patches as multicomponent signals.

    PubMed

    Grether, Gregory F; Kolluru, Gita R; Nersissian, Karen

    2004-08-01

    Colour patches are complex traits, the components of which may evolve independently through a variety of mechanisms. Although usually treated as simple, two-dimensional characters and classified as either structural or pigmentary, in reality colour patches are complicated, three-dimensional structures that often contain multiple pigment types and structural features. The basic dermal chromatophore unit of fishes, reptiles and amphibians consists of three contiguous cell layers. Xanthophores and erythrophores in the outermost layer contain carotenoid and pteridine pigments that absorb short-wave light; iridophores in the middle layer contain crystalline platelets that reflect light back through the xanthophores; and melanophores in the basal layer contain melanins that absorb light across the spectrum. Changes in any one component of a chromatophore unit can drastically alter the reflectance spectrum produced, and for any given adaptive outcome (e.g. an increase in visibility), there may be multiple biochemical or cellular routes that evolution could take, allowing for divergent responses by different populations or species to similar selection regimes. All of the mechanisms of signal evolution that previously have been applied to single ornaments (including whole colour patches) could potentially be applied to the individual components of colour patches. To reach a complete understanding of colour patch evolution, however, it may be necessary to take an explicitly multi-trait approach. Here, we review multiple trait evolution theory and the basic mechanisms of colour production in fishes, reptiles and amphibians, and use a combination of computer simulations and empirical examples to show how multiple trait evolution theory can be applied to the components of single colour patches. This integrative perspective on animal colouration opens up a host of new questions and hypotheses. We offer specific, testable functional hypotheses for the most common pigmentary

  8. Methods of Making and Using Shape Memory Polymer Composite Patches

    NASA Technical Reports Server (NTRS)

    Hood, Patrick J.

    2011-01-01

    A method of repairing a composite component having a damaged area including: laying a composite patch over the damaged area: activating the shape memory polymer resin to easily and quickly mold said patch to said damaged area; deactivating said shape memory polymer so that said composite patch retains the molded shape; and bonding said composite patch to said damaged part.

  9. Measles vaccination using a microneedle patch.

    PubMed

    Edens, Chris; Collins, Marcus L; Ayers, Jessica; Rota, Paul A; Prausnitz, Mark R

    2013-07-25

    Measles vaccination programs would benefit from delivery methods that decrease cost, simplify logistics, and increase safety. Conventional subcutaneous injection is limited by the need for skilled healthcare professionals to reconstitute and administer injections, and by the need for safe needle handling and disposal to reduce the risk of disease transmission through needle re-use and needlestick injury. Microneedles are micron-scale, solid needles coated with a dry formulation of vaccine that dissolves in the skin within minutes after patch application. By avoiding the use of hypodermic needles, vaccination using a microneedle patch could be carried out by minimally trained personnel with reduced risk of blood-borne disease transmission. The goal of this study was to evaluate measles vaccination using a microneedle patch to address some of the limitations of subcutaneous injection. Viability of vaccine virus dried onto a microneedle patch was stabilized by incorporation of the sugar, trehalose, and loss of viral titer was less than 1 log10(TCID50) after storage for at least 30 days at room temperature. Microneedle patches were then used to immunize cotton rats with the Edmonston-Zagreb measles vaccine strain. Vaccination using microneedles at doses equaling the standard human dose or one-fifth the human dose generated neutralizing antibody levels equivalent to those of a subcutaneous immunization at the same dose. These results show that measles vaccine can be stabilized on microneedles and that vaccine efficiently reconstitutes in vivo to generate a neutralizing antibody response equivalent to that generated by subcutaneous injection.

  10. Transdermal patch drug delivery interactions with exercise.

    PubMed

    Lenz, Thomas L; Gillespie, Nicole

    2011-03-01

    Transdermal drug delivery systems, such as the transdermal patch, continue to be a popular and convenient way to administer medications. There are currently several medications that use a transdermal patch drug delivery system. This article describes the potential untoward side effects of increased drug absorption through the use of a transdermal patch in individuals who exercise or participate in sporting events. Four studies have been reported that demonstrate a significant increase in the plasma concentration of nitroglycerin when individuals exercise compared with rest. Likewise, several case reports and two studies have been conducted that demonstrate nicotine toxicity and increased plasma nicotine while wearing a nicotine patch in individuals who exercise or participate in sporting events compared with rest. Healthcare providers, trainers and coaches should be aware of proper transdermal patch use, especially while exercising, in order to provide needed information to their respective patients and athletes to avoid potential untoward side effects. Particular caution should be given to individuals who participate in an extreme sporting event of long duration. Further research that includes more medications is needed in this area.

  11. Activated Membrane Patches Guide Chemotactic Cell Motility

    PubMed Central

    Hecht, Inbal; Skoge, Monica L.; Charest, Pascale G.; Ben-Jacob, Eshel; Firtel, Richard A.; Loomis, William F.; Levine, Herbert; Rappel, Wouter-Jan

    2011-01-01

    Many eukaryotic cells are able to crawl on surfaces and guide their motility based on environmental cues. These cues are interpreted by signaling systems which couple to cell mechanics; indeed membrane protrusions in crawling cells are often accompanied by activated membrane patches, which are localized areas of increased concentration of one or more signaling components. To determine how these patches are related to cell motion, we examine the spatial localization of RasGTP in chemotaxing Dictyostelium discoideum cells under conditions where the vertical extent of the cell was restricted. Quantitative analyses of the data reveal a high degree of spatial correlation between patches of activated Ras and membrane protrusions. Based on these findings, we formulate a model for amoeboid cell motion that consists of two coupled modules. The first module utilizes a recently developed two-component reaction diffusion model that generates transient and localized areas of elevated concentration of one of the components along the membrane. The activated patches determine the location of membrane protrusions (and overall cell motion) that are computed in the second module, which also takes into account the cortical tension and the availability of protrusion resources. We show that our model is able to produce realistic amoeboid-like motion and that our numerical results are consistent with experimentally observed pseudopod dynamics. Specifically, we show that the commonly observed splitting of pseudopods can result directly from the dynamics of the signaling patches. PMID:21738453

  12. Characterizing the morphology of protein binding patches.

    PubMed

    Malod-Dognin, Noël; Bansal, Achin; Cazals, Frédéric

    2012-12-01

    Let the patch of a partner in a protein complex be the collection of atoms accounting for the interaction. To improve our understanding of the structure-function relationship, we present a patch model decoupling the topological and geometric properties. While the geometry is classically encoded by the atomic positions, the topology is recorded in a graph encoding the relative position of concentric shells partitioning the interface atoms. The topological-geometric duality provides the basis of a generic dynamic programming-based algorithm comparing patches at the shell level, which may favor topological or geometric features. On the biological side, we address four questions, using 249 cocrystallized heterodimers organized in biological families. First, we dissect the morphology of binding patches and show that Nature enjoyed the topological and geometric degrees of freedom independently while retaining a finite set of qualitatively distinct topological signatures. Second, we argue that our shell-based comparison is effective to perform atomic-level comparisons and show that topological similarity is a less stringent than geometric similarity. We also use the topological versus geometric duality to exhibit topo-rigid patches, whose topology (but not geometry) remains stable upon docking. Third, we use our comparison algorithms to infer specificity-related information amidst a database of complexes. Finally, we exhibit a descriptor outperforming its contenders to predict the binding affinities of the affinity benchmark. The softwares developed with this article are availablefrom http://team.inria.fr/abs/vorpatch_compatch/.

  13. Microneedle patches for vaccination in developing countries.

    PubMed

    Arya, Jaya; Prausnitz, Mark R

    2016-10-28

    Millions of people die of infectious diseases each year, mostly in developing countries, which could largely be prevented by the use of vaccines. While immunization rates have risen since the introduction of the Expanded Program on Immunization (EPI), there remain major challenges to more effective vaccination in developing countries. As a possible solution, microneedle patches containing an array of micron-sized needles on an adhesive backing have been developed to be used for vaccine delivery to the skin. These microneedle patches can be easily and painlessly applied by pressing against the skin and, in some designs, do not leave behind sharps waste. The patches are single-dose, do not require reconstitution, are easy to administer, have reduced size to simplify storage, transportation and waste disposal, and offer the possibility of improved vaccine immunogenicity, dose sparing and thermostability. This review summarizes vaccination challenges in developing countries and discusses advantages that microneedle patches offer for vaccination to address these challenges. We conclude that microneedle patches offer a powerful new technology that can enable more effective vaccination in developing countries.

  14. Surface patterning of nanoparticles with polymer patches

    SciTech Connect

    Choueiri, Rachelle M.; Galati, Elizabeth; Thérien-Aubin, Héloïse; Klinkova, Anna; Larin, Egor M.; Querejeta-Fernández, Ana; Han, Lili; Xin, Huolin L.; Gang, Oleg; Zhulina, Ekaterina B.; Rubinstein, Michael; Kumacheva, Eugenia

    2016-08-24

    Patterning of colloidal particles with chemically or topographically distinct surface domains (patches) has attracted intense research interest. Surface-patterned particles act as colloidal analogues of atoms and molecules serve as model systems in studies of phase transitions in liquid systems, behave as ‘colloidal surfactants’ and function as templates for the synthesis of hybrid particles. The generation of micrometre- and submicrometre-sized patchy colloids is now efficient but surface patterning of inorganic colloidal nanoparticles with dimensions of the order of tens of nanometres is uncommon. Such nanoparticles exhibit size- and shape-dependent optical, electronic and magnetic properties, and their assemblies show new collective properties. At present, nanoparticle patterning is limited to the generation of two-patch nanoparticles and nanoparticles with surface ripples or a ‘raspberry’ surface morphology. We demonstrate nanoparticle surface patterning, which utilizes thermodynamically driven segregation of polymer ligands from a uniform polymer brush into surface-pinned micelles following a change in solvent quality. Patch formation is reversible but can be permanently preserved using a photocrosslinking step. The methodology offers the ability to control the dimensions of patches, their spatial distribution and the number of patches per nanoparticle, in agreement with a theoretical model. The versatility of the strategy is demonstrated by patterning nanoparticles with different dimensions, shapes and compositions, tethered with various types of polymers and subjected to different external stimuli. Furthermore, these patchy nanocolloids have potential applications in fundamental research, the self-assembly of nanomaterials, diagnostics, sensing and colloidal stabilization.

  15. Surface patterning of nanoparticles with polymer patches

    NASA Astrophysics Data System (ADS)

    Choueiri, Rachelle M.; Galati, Elizabeth; Thérien-Aubin, Héloïse; Klinkova, Anna; Larin, Egor M.; Querejeta-Fernández, Ana; Han, Lili; Xin, Huolin L.; Gang, Oleg; Zhulina, Ekaterina B.; Rubinstein, Michael; Kumacheva, Eugenia

    2016-10-01

    Patterning of colloidal particles with chemically or topographically distinct surface domains (patches) has attracted intense research interest. Surface-patterned particles act as colloidal analogues of atoms and molecules, serve as model systems in studies of phase transitions in liquid systems, behave as ‘colloidal surfactants’ and function as templates for the synthesis of hybrid particles. The generation of micrometre- and submicrometre-sized patchy colloids is now efficient, but surface patterning of inorganic colloidal nanoparticles with dimensions of the order of tens of nanometres is uncommon. Such nanoparticles exhibit size- and shape-dependent optical, electronic and magnetic properties, and their assemblies show new collective properties. At present, nanoparticle patterning is limited to the generation of two-patch nanoparticles, and nanoparticles with surface ripples or a ‘raspberry’ surface morphology. Here we demonstrate nanoparticle surface patterning, which utilizes thermodynamically driven segregation of polymer ligands from a uniform polymer brush into surface-pinned micelles following a change in solvent quality. Patch formation is reversible but can be permanently preserved using a photocrosslinking step. The methodology offers the ability to control the dimensions of patches, their spatial distribution and the number of patches per nanoparticle, in agreement with a theoretical model. The versatility of the strategy is demonstrated by patterning nanoparticles with different dimensions, shapes and compositions, tethered with various types of polymers and subjected to different external stimuli. These patchy nanocolloids have potential applications in fundamental research, the self-assembly of nanomaterials, diagnostics, sensing and colloidal stabilization.

  16. The effect of direct interspecific competition on patch exploitation strategies in parasitoid wasps.

    PubMed

    Mohamad, Rihab; Wajnberg, Eric; Monge, Jean-Paul; Goubault, Marlène

    2015-01-01

    The presence of competitors may affect the pay-off of individuals' foraging strategies. They should therefore modify their resource exploitation decisions accordingly. In such a direct competition situation, theory predicts that individuals should stay longer on a resource patch than when foraging alone. However, models predicting patch residence time focus on intraspecific competition without agonistic interactions. Here, we investigate the patch use strategies of females of two parasitoid species, Eupelmus vuilleti and Dinarmus basalis, attacking the same host, Callosobruchus maculatus, knowing that D. basalis is more aggressive and can exclude E. vuilleti during pairwise contests for single hosts. Our results showed that time allocation and oviposition strategies differed in relation to the species and type of competition (i.e., presence/absence of competitor, simultaneous/sequential female introduction or resident/intruder female). Eupelmus vuilleti females tended to wait in the patch surroundings for D. basalis females' departure to return and exploit hosts parasitized by the opponent (after destruction of her eggs). In contrast, D. basalis females tended to self-superparasitize and stay motionless near the hosts. After detecting an E. vuilleti female entering the patch, they attacked and chased her permanently from the patch. Females of both species spent less time in the patch when faced with a competitor than when alone. This study is the first to test the influence of direct interspecific competition and arrival order on patch exploitation strategies in parasitoid species, and highlights the necessity to include agonistic behaviors in theoretical models predicting optimal patch residence time in competitive situations.

  17. Plant community response to landscape connectivity and patch shape.

    SciTech Connect

    Damschen, Ellen I.

    2005-07-01

    Ph.D Dissertation. North Carolina State University. Raleigh, North Carolina. 135 pp. Abstract. Land transformation is the single most important factor promoting the global loss of terrestrial biological diversity. Remaining habitat fragments contain more edges, less interior habitat, and are more isolated from other habitat fragments, all of which decrease rates of colonization following local extinctions, reduce reproductive rates and gene flow between populations, and ultimately lead to species extinctions. The best approach to prevent species loss, therefore, is to preserve greater areas of habitat. In many cases, however, habitat has already been fragmented and strategies are needed to configure and manage the remaining land. Land managers often create reserve networks that incorporate the use of landscape corridors, linear strips of habitat connecting isolated patches, to reduce species loss by increasing colonizations and decreasing extinctions. Most empirical tests of corridors have been limited to individuals and populations, leaving corridor effects on diversity largely unknown, especially at large spatial scales. Additionally, only a handful of studies have examined corridor effects on plants, which may be especially sensitive to the abiotic changes resulting from alterations in patch shape due to dispersal limitation. Using one of the best-replicated, large-scale habitat fragmentation experiments, I tested explicitly for corridor effects on plant community diversity and composition by examining the established plant community and the soil seedbank. My experimental design distinguished among the three possible ways corridors can affect between-patch processes: by acting as a movement conduit between connected patches (“connectivity effects”), by increasing area alone (“area effects”), and by intercepting organisms moving across the landscape and filtering them into connected patches (“drift-fence effects”). Additionally, I tested for the

  18. Assessment of the effectiveness of nontransdermal energy patches on muscle endurance and power.

    PubMed

    Jacobson, Bert H; Smith, Doug B; Stemm, John D; Warren, Aric J; O'Brien, Matt S; Glass, Rob G

    2008-05-01

    Claims of recently developed energy patches suggest that organic nanoscale biomolecular "antennas" produced by L and D-stereoisomers resonate at frequencies in unison with molecules in the cells inducing electron flow to assists in recruiting calcium ions, allowing greater muscle fiber recruitment during muscle contraction. The purpose of the study was to assess the efficacy of energy patches in the performance of selected muscle power and endurance measures. After a 5-minute warm-up and stretch, 41 college varsity football players (age, 20.37 +/- 1.24 years; height, 169.91 +/- 7.44 cm; weight, 109.45 +/- 19.85 kg) were pre-tested on 102-kg maximal bench press repetitions, standing vertical jump, grip strength, peak torque, torque to body weight, total work, average power, and average torque as measured by 50 repetitions of leg extensions at 180 degrees .s. The following week, the players were randomly assigned the experimental or placebo patches. After placement of the patches, the participants again completed a 5-minute warm-up, followed by the identical pre-test protocol. Repeated-measures ANOVAs were used to compare resultant data. No significant group interaction effects were found between experimental and placebo patches for maximal bench press repetitions (p = 0.48), vertical jump distance (p = 0.39), grip strength (p = 0.29), total work (p = 0.26), torque to body weight (p = 0.05), average peak torque (p = 0.08), and average power (p = 0.05). A significant increase occurred in the experimental group for peak torque (p = 0.04). It was concluded that the energy patches significantly improved performance over placebo patches in one of the eight variables tested and registered near significance in two additional variables. However, inconsistency in overall results demands further studies to determine the reliability in improvement of performance in the presence of energy patches.

  19. Adhesive RFID Sensor Patch for Monitoring of Sweat Electrolytes.

    PubMed

    Rose, Daniel P; Ratterman, Michael E; Griffin, Daniel K; Hou, Linlin; Kelley-Loughnane, Nancy; Naik, Rajesh R; Hagen, Joshua A; Papautsky, Ian; Heikenfeld, Jason C

    2015-06-01

    Wearable digital health devices are dominantly found in rigid form factors such as bracelets and pucks. An adhesive radio-frequency identification (RFID) sensor bandage (patch) is reported, which can be made completely intimate with human skin, a distinct advantage for chronological monitoring of biomarkers in sweat. In this demonstration, a commercial RFID chip is adapted with minimum components to allow potentiometric sensing of solutes in sweat, and surface temperature, as read by an Android smartphone app with 96% accuracy at 50 mM Na(+) (in vitro tests). All circuitry is solder-reflow integrated on a standard Cu/polyimide flexible-electronic layer including an antenna, but while also allowing electroplating for simple integration of exotic metals for sensing electrodes. Optional paper microfluidics wick sweat from a sweat porous adhesive allowing flow to the sensor, or the sensor can be directly contacted to the skin. The wearability of the patch has been demonstrated for up to seven days, and includes a protective textile which provides a feel and appearance similar to a standard Band-Aid. Applications include hydration monitoring, but the basic capability is extendable to other mM ionic solutes in sweat (Cl(-), K(+), Mg(2+), NH4(+), and Zn(2+)). The design and fabrication of the patch are provided in full detail, as the basic components could be useful in the design of other wearable sensors.

  20. Evolution of density- and patch-size-dependent dispersal rates.

    PubMed Central

    Poethke, Hans Joachim; Hovestadt, Thomas

    2002-01-01

    Based on a marginal value approach, we derive a nonlinear expression for evolutionarily stable (ES) dispersal rates in a metapopulation with global dispersal. For the general case of density-dependent population growth, our analysis shows that individual dispersal rates should decrease with patch capacity and-beyond a certain threshold-increase with population density. We performed a number of spatially explicit, individual-based simulation experiments to test these predictions and to explore further the relevance of variation in the rate of population increase, density dependence, environmental fluctuations and dispersal mortality on the evolution of dispersal rates. They confirm the predictions of our analytical approach. In addition, they show that dispersal rates in metapopulations mostly depend on dispersal mortality and inter-patch variation in population density. The latter is dominantly driven by environmental fluctuations and the rate of population increase. These conclusions are not altered by the introduction of neighbourhood dispersal. With patch capacities in the order of 100 individuals, kin competition seems to be of negligible importance for ES dispersal rates except when overall dispersal rates are low. PMID:11916481

  1. Role of Bacterial Communities in the Natural Suppression of Rhizoctonia solani Bare Patch Disease of Wheat (Triticum aestivum L.)

    PubMed Central

    Yin, Chuntao; Hulbert, Scot H.; Schroeder, Kurtis L.; Mavrodi, Olga; Mavrodi, Dmitri; Dhingra, Amit; Schillinger, William F.

    2013-01-01

    Rhizoctonia bare patch and root rot disease of wheat, caused by Rhizoctonia solani AG-8, develops as distinct patches of stunted plants and limits the yield of direct-seeded (no-till) wheat in the Pacific Northwest of the United States. At the site of a long-term cropping systems study near Ritzville, WA, a decline in Rhizoctonia patch disease was observed over an 11-year period. Bacterial communities from bulk and rhizosphere soil of plants from inside the patches, outside the patches, and recovered patches were analyzed by using pyrosequencing with primers designed for 16S rRNA. Taxa in the class Acidobacteria and the genus Gemmatimonas were found at higher frequencies in the rhizosphere of healthy plants outside the patches than in that of diseased plants from inside the patches. Dyella and Acidobacteria subgroup Gp7 were found at higher frequencies in recovered patches. Chitinophaga, Pedobacter, Oxalobacteriaceae (Duganella and Massilia), and Chyseobacterium were found at higher frequencies in the rhizosphere of diseased plants from inside the patches. For selected taxa, trends were validated by quantitative PCR (qPCR), and observed shifts of frequencies in the rhizosphere over time were duplicated in cycling experiments in the greenhouse that involved successive plantings of wheat in Rhizoctonia-inoculated soil. Chryseobacterium soldanellicola was isolated from the rhizosphere inside the patches and exhibited significant antagonism against R. solani AG-8 in vitro and in greenhouse tests. In conclusion, we identified novel bacterial taxa that respond to conditions affecting bare patch disease symptoms and that may be involved in suppression of Rhizoctonia root rot and bare batch disease. PMID:24056471

  2. PL-PatchSurfer: A Novel Molecular Local Surface-Based Method for Exploring Protein-Ligand Interactions

    PubMed Central

    Hu, Bingjie; Zhu, Xiaolei; Monroe, Lyman; Bures, Mark G.; Kihara, Daisuke

    2014-01-01

    Structure-based computational methods have been widely used in exploring protein-ligand interactions, including predicting the binding ligands of a given protein based on their structural complementarity. Compared to other protein and ligand representations, the advantages of a surface representation include reduced sensitivity to subtle changes in the pocket and ligand conformation and fast search speed. Here we developed a novel method named PL-PatchSurfer (Protein-Ligand PatchSurfer). PL-PatchSurfer represents the protein binding pocket and the ligand molecular surface as a combination of segmented surface patches. Each patch is characterized by its geometrical shape and the electrostatic potential, which are represented using the 3D Zernike descriptor (3DZD). We first tested PL-PatchSurfer on binding ligand prediction and found it outperformed the pocket-similarity based ligand prediction program. We then optimized the search algorithm of PL-PatchSurfer using the PDBbind dataset. Finally, we explored the utility of applying PL-PatchSurfer to a larger and more diverse dataset and showed that PL-PatchSurfer was able to provide a high early enrichment for most of the targets. To the best of our knowledge, PL-PatchSurfer is the first surface patch-based method that treats ligand complementarity at protein binding sites. We believe that using a surface patch approach to better understand protein-ligand interactions has the potential to significantly enhance the design of new ligands for a wide array of drug-targets. PMID:25167137

  3. Vegetation patches increase wind-blown litter accumulation in a semi-arid steppe of northern China

    NASA Astrophysics Data System (ADS)

    Yan, Yuchun; Xin, Xiaoping; Xu, Xingliang; Wang, Xu; Yan, Ruirui; Murray, Philip J.

    2016-12-01

    Litter decomposition is an important source of soil organic matter and nutrients; however, few studies have explored how vegetation patches affect wind-driven litter mobility and accumulation. In this study, we aimed to test the following hypotheses: (1) vegetation patches can reduce litter removal and facilitate litter accumulation, (2) litter mobility results in the heterogeneous redistribution of carbon and nutrients over the land surface, and (3) litter removal rates differ among different litter types (e.g., leaf and stem). Four vegetation patch types and six litter types were used to investigate the impacts of vegetation patches on litter mobility and accumulation. The results show that compared with almost bare ground patches, patches with vegetation cover had significantly higher litter accumulation, with the shrub patch type having the highest accumulation amount. The rate of litter removal due to wind was highest for the almost bare surface type (P4) and lowest for the shrub patch (P1) and Stipa grandis community (P2) types. There were significant differences in the removal rate among the different litter types. These findings indicate that wind-based litter redistribution among bare, S. grandis-dominated, and shrub-dominated patches is at least partially responsible for increasing the spatial heterogeneity of resources on a landscape scale.

  4. Can we go beyond burned area assessment with fire patch metrics from global remote rensing?

    NASA Astrophysics Data System (ADS)

    Nogueira Pereira Messias, Joana; Ruffault, Julien; Chuvieco, Emilio; Mouillot, Florent

    2016-04-01

    Fire is a major event influencing global biogeochemical cycles and contribute to the emissions of CO2 and other greenhouse gases to the atmosphere. Global burned area (BA) datasets from remote sensing have provided the fruitful information for quantifying carbon emissions in global biogeochemical models, and for DGVM's benchmarking. Patch level analysis from pixel level information recently emerged as an informative additional feature of the regime as fire size distribution. The aim of this study is to evaluate the ability of global BA products to accurately represent characteristics of fire patches (size, complexity shape and spatial orientation). We selected a site in the Brazilian savannas (Cerrado), one of the most fire prone biome and one of the validation test site for the ESA fire-Cci project. We used the pixel-level burned area detected by Landsat, MCD45A1 and the newly delivered MERIS ESA fire-Cci for the period 2002-2009. A flood-fill algorithm adapted from Archibald and Roy (2009) was used to identify the individual fire patches (patch ID) according to the burned date (BD). For each patch ID, we calculated a panel of patch metrics as area, perimeter and core area, shape complexity (shape index and fractal dimension) and the feature of the ellipse fitted over the spatial distribution of pixels composing the patch (eccentricity and direction of the main axis). Paired fire patches overlapping between each BA products were compared. The correlation between patch metrics were evaluated by linear regression models for each inter-product comparison according to fire size classes. Our results showed significant patch overlaps (>30%) between products for patches with areas larger than 270ha, with more than 90% of patches overlapping between MERIS and MCD45A1. Fire Patch metrics correlations showed R2>0.6 for all comparisons of patch Area and Core Area, with a slope of 0.99 between MERIS and MCD45A1 illustrating the agreement between the two global products. The

  5. Deformation of Polar Cap Patches During Substorms

    NASA Astrophysics Data System (ADS)

    Zou, S.; Ridley, A. J.; Nicolls, M. J.; Coster, A. J.; Thomas, E. G.; Ruohoniemi, J. M.; Hampton, D.

    2015-12-01

    Polar cap patches refer to the islands of high F-region plasma density within the polar cap. Their formation on the dayside and deformation on the nightside are not well understood. The F-layer ionosphere density is strongly influenced by electric field, thermospheric wind as well as soft particle precipitation. This study combines observations from multiple instruments, including Poker Flat incoherent scatter radar, GPS TEC and optical instruments, as well as the Global Ionosphere and Thermosphere Model (GITM), to investigate the effects of highly structured electric fields and winds on the deformation of polar cap patches during substorms. We will also discuss variations of the auroral emissions associated with the patch evolution.

  6. Tunable nano dispersed LC based patch antenna

    NASA Astrophysics Data System (ADS)

    Karim, Afaque; Yadav, Harsh; Ahmad, Shakeb

    2015-06-01

    This paper presents Patch antenna based on pure and Nano dispersed liquid crystals (LCs) for earth and space applications. Patch antenna are one of the most attractive antennas designed for RF frequency. To fulfill the demand of modern antenna i.e. tunability, a design of LC based patch antenna with optimum frequency of 15 GHz is investigated. In this design, NLC and ZnO doped NLC were used as a dielectric substrate. Its dielectric permittivity was controlled by biasing voltage. The dielectric properties of the 4-Cyano-4' -pentylbiphenyl (5CB) nematic liquid crystal (NLC), and NLC doped with Zinc oxide (ZnO) Nanoparticles was studied at room temperature. The concentration of doping material was 0.5% by w.t. in ZnO. Results shows that dielectric parameters are strong function of frequency and applied bias voltage. Moreover, Using doped NLC as dielectric substrate one gets more tunability or shift in resonant frequency in the proposed geometry.

  7. Cell repair: Revisiting the patch hypothesis

    PubMed Central

    Davenport, Nicholas R.

    2016-01-01

    ABSTRACT Plasma membrane damage elicits a complex and dynamic cellular response. A vital component of this response, membrane resealing, is thought to arise from fusion of intracellular membranous compartments to form a temporary, impermeant patch at the site of damage; however, this hypothesis has been difficult to confirm visually. By utilizing advanced microscopy technologies with high spatiotemporal resolution in wounded Xenopus laevis oocytes, we provide the first direct visualization of the membrane fusion events predicted by the patch hypothesis; we show the barrier formed by patching is capable of abating exchange of material across the plasma membrane within seconds. Profound changes also occur to the plasma membrane surrounding wounds; lipid remodeling is accompanied by membrane fusion events, both conventional (e.g., exocytosis) and novel (e.g., “explodosis”). Further, we reveal additional complexity in wound-induced subcellular patterning, supporting existing evidence that extensive interactions between lipid, protein, and ionic signaling pathways shape the cellular wound response. PMID:28042380

  8. Boolean Operations with Prism Algebraic Patches

    PubMed Central

    Bajaj, Chandrajit; Paoluzzi, Alberto; Portuesi, Simone; Lei, Na; Zhao, Wenqi

    2009-01-01

    In this paper we discuss a symbolic-numeric algorithm for Boolean operations, closed in the algebra of curved polyhedra whose boundary is triangulated with algebraic patches (A-patches). This approach uses a linear polyhedron as a first approximation of both the arguments and the result. On each triangle of a boundary representation of such linear approximation, a piecewise cubic algebraic interpolant is built, using a C1-continuous prism algebraic patch (prism A-patch) that interpolates the three triangle vertices, with given normal vectors. The boundary representation only stores the vertices of the initial triangulation and their external vertex normals. In order to represent also flat and/or sharp local features, the corresponding normal-per-face and/or normal-per-edge may be also given, respectively. The topology is described by storing, for each curved triangle, the two triples of pointers to incident vertices and to adjacent triangles. For each triangle, a scaffolding prism is built, produced by its extreme vertices and normals, which provides a containment volume for the curved interpolating A-patch. When looking for the result of a regularized Boolean operation, the 0-set of a tri-variate polynomial within each such prism is generated, and intersected with the analogous 0-sets of the other curved polyhedron, when two prisms have non-empty intersection. The intersection curves of the boundaries are traced and used to decompose each boundary into the 3 standard classes of subpatches, denoted in, out and on. While tracing the intersection curves, the locally refined triangulation of intersecting patches is produced, and added to the boundary representation. PMID:21516262

  9. Dynamics of skimming flow in the wake of a vegetation patch

    NASA Astrophysics Data System (ADS)

    Mayaud, Jerome R.; Wiggs, Giles F. S.; Bailey, Richard M.

    2016-09-01

    Dryland vegetation is often spatially patchy, and so affects wind flow in complex ways. Theoretical models and wind tunnel testing have shown that skimming flow develops above vegetation patches at high plant densities, resulting in little or no wind erosion in these zones. Understanding the dynamics of skimming flow is therefore important for predicting sediment transport and bedform development in dryland areas. However, no field-based data are available describing turbulent airflow dynamics in the wake of vegetation patches. In this study, turbulent wind flow was examined using high-frequency (10 Hz) sonic anemometry at four measurement heights (0.30 m, 0.55 m, 1.10 m and 1.65 m) along a transect in the lee of an extensive patch of shrubs (z = 1.10 m height) in Namibia. Spatial variations in mean wind velocity, horizontal Reynolds stresses and coherent turbulent structures were analysed. We found that wind velocity in the wake of the patch effectively recovered over ∼12 patch heights (h) downwind, which is 2-5 h longer than previously reported recovery lengths for individual vegetation elements and two-dimensional wind fences. This longer recovery can be attributed to a lack of flow moving around the obstacle in the patch case. The step-change in roughness between the patch canopy and the bare surface in its wake resulted in an initial peak in resultant horizontal shear stress (τr) followed by significant decrease downwind. In contrast to τr , horizontal normal Reynolds stress (u‧2 ‾) progressively increased along the patch wake. A separation of the upper shear layer at the leeside edge of the patch was observed, and a convergence of τr curves implies the formation of a constant stress layer by ∼20 h downwind. The use of τr at multiple heights is found to be a useful tool for identifying flow equilibration in complex aerodynamic regimes. Quadrant analysis revealed elevated frequencies of Q2 (ejection) and Q4 (sweep) events in the immediate lee of the

  10. Epidural blood patch and acute varicella.

    PubMed

    Martin, David P; Bergman, Bradley D; Berger, Ines H

    2004-12-01

    We present the case of a 38-yr-old woman who required an epidural blood patch in the context of acute varicella (chickenpox). The unique risks in this case include the possible triggering of central nervous system complications after the introduction of viremic blood into the epidural or intrathecal space. However, the risk was believed to be acceptable because the patient was receiving antiviral coverage. She enjoyed complete relief of her headache but experienced transient back and leg pain. Leptomeningeal irritation caused by acute varicella infection may put patients at increased risk for pain after epidural blood patch.

  11. Patch Clamping Protoplasts from Vascular Plants 1

    PubMed Central

    Elzenga, J. Theo M.; Keller, Christopher P.; Van Volkenburgh, Elizabeth

    1991-01-01

    A method is described for the isolation of protoplasts (Pisum sativum, Phaseolus vulgaris, Avena sativa, Arabidopsis thaliana) in preparation for ion flux studies using patch clamp electrophysiology. Protoplasts that have been exposed to hydrolytic, cell wall degrading, enzymes for as little as 5 minutes form gigaseals (seal resistance higher than 10 giga Ohm) with the patch pipette with success rates greater than 40%. Sealing of these protoplasts is fast, averaging less than 2 minutes. This method yields high rates of gigaseal formation in a variety of tissues from both monocots and dicots and will enhance data collection in ion flux studies of plasma membranes of vascular plants. PMID:16668586

  12. Lightweight Material Patches Allow for Quick Repairs

    NASA Technical Reports Server (NTRS)

    2010-01-01

    Cornerstone Research Group Inc., of Dayton, Ohio, has been the recipient of 16 Small Business Innovation Research (SBIR) contracts with NASA with a variety of different focuses, including projects like creating inflatable structures for radio frequency antennas and, most recently, healable polymer matrix composites for future space vehicles. One of its earlier SBIR contracts, with Kennedy Space Center, led to the development of a new type of structural patch for a variety of consumer uses: Rubbn Repair, for automotive uses; and Rec Repair for the outdoors and adventure market. Both are flexible, heat-activated structural patches.

  13. Grid flexibility and patching techniques

    NASA Technical Reports Server (NTRS)

    Keith, T. G.; Smith, L. W.; Yung, C. N.; Barthelson, S. H.; Dewitt, K. J.

    1984-01-01

    The numerical determination of combustor flowfields is of great value to the combustor designer. An a priori knowledge of the flow behavior can speed the combustor design process and reduce the number of experimental test rigs required to arrive at an optimal design. Even 2-D steady incompressible isothermal flow predictions are of use; many codes of this kind are available, each employing different techniques to surmount the difficulties arising from the nonlinearity of the governing equations and from typically irregular combustor geometries. Mapping techniques (algebraic and elliptic PDE), and adaptive grid methods (both multi-grid and grid embedding) as applied to axisymmetric combustors are discussed.

  14. Patches for Carotid Artery Endarterectomy: Current Materials and Prospects

    PubMed Central

    Muto, Akihito; Nishibe, Toshiya; Dardik, Herbert; Dardik, Alan

    2009-01-01

    Patch angioplasty is commonly performed after carotid endarterectomy. Randomized prospective trials and meta-analyses have documented improved rates of perioperative and long-term stroke prevention as well as reduced rates of restenosis for patches compared to primary closure of the arteriotomy. Although use of vein patches is considered to be the “gold standard” for patch closure, newer generations of synthetic and biological materials rival outcomes associated with vein patches. Future bioengineered patches are likely to optimize patch performance, both by achieving minimal stroke risk and long-term rates of restenosis, as well as by minimizing the risk of unusual complications of prosthetic patches such as infection and pseudoaneurysm formation; in addition, lessons from bioengineered patches will likely enable construction of bioengineered and tissue-engineered bypass grafts. PMID:19563972

  15. Critical patch sizes for food-web modules.

    PubMed

    Martinson, Holly M; Fagan, William F; Denno, Robert F

    2012-08-01

    Because patch size and connectivity may strongly impact the assemblage of species that occur on a patch, the types of food-web interactions that occur among those species may also depend on spatial structure. Here, we identify whether food-web interactions among salt-marsh-inhabiting arthropods vary with patch size and connectivity, and how such changes in trophic structure might feed back to influence the spatial distribution of prey. In a multiyear survey, patch-restricted predators exhibited steeper occupancy-patch-size relationships than herbivores, and species' critical patch sizes were correlated with overall rarity. As a result, the presence of food-web modules depended strongly on patch size: large and well-connected patches supported complex food-web modules, but only the simplest modules involving the most abundant species were found on small patches. Habitat-generalist spiders dominated on small patches, and predation pressure from such species may contribute to the observed lower densities of mesopredators on small patches. Overall, patch size and connectivity influenced the types of modules present on a patch through differential loss of rare, patch-restricted predators, but predation by generalist predators may be a key mechanism influencing the spatial structure of certain prey species.

  16. Multimode Broad-Band Patch Antennas

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R.

    2003-01-01

    Microstrip patch antennas of a proposed type would be tunable over broad wavelength ranges. These antennas would be attractive for use in a variety of microwave communication systems in which there are requirements for transmission and/or reception at multiple, widely separated frequencies. Prior efforts to construct tunable microstrip patch antennas have involved integration of microstrip circuitry with, variously, ferrite films with magneticfield tuning, solid-state electronic tuning devices, or piezoelectric tuning actuators. Those efforts have been somewhat successful, but have yielded tuning ranges of 20 percent and smaller much smaller than needed in typical practical cases. Like prior microstrip patch antennas (both tunable and non-tunable), the proposed antennas would have instantaneous bandwidths of about 1 percent of their nominal or resonance frequencies. However, these would be tunable over much broader frequency ranges as much as several octaves, depending on specific designs. They could be fabricated relatively simply and inexpensively by use of conventional photolithography, and without need for integration with solid-state electronic or piezoelectric control devices. An antenna as proposed (see figure) would include a microstrip patch radiating element on a thin ferroelectric film on a semiconductor substrate with a ground-plane conductor on the underside of the substrate. The ferroelectric film could be, for example, SrTiO3 with a thickness of the order of 1 or 2 micrometers.

  17. Juno Microwave Radiometer Patch Array Antennas

    NASA Technical Reports Server (NTRS)

    Chamberlain, N.; Chen, J.; Focardi, P.; Hodges, R.; Hughes, R.; Jakoboski, J.; Venkatesan, J.; Zawadzki, M.

    2009-01-01

    Juno is a mission in the NASA New Frontiers Program with the goal of significantly improving our understanding of the formation and structure of Jupiter. This paper discusses the modeling and measurement of the two patch array antennas. An overview of the antenna architecture, design and development at JPL is provided, along with estimates of performance and the results of measurements.

  18. Soil, Seeds, and the Pumpkin Patch!

    ERIC Educational Resources Information Center

    Phillips, Marianne; Vowell, Julie

    2013-01-01

    "Soil, Seeds, and the Pumpkin Patch!" is an integrated unit designed to provide elementary school teachers with ideas for using hands-on activities, fostering inquiry and valuable discussion, and using technology as a learning tool. This unit integrates science with language arts, mathematics, literature, and technology. During this unit, students…

  19. Surface patterning of nanoparticles with polymer patches

    DOE PAGES

    Choueiri, Rachelle M.; Galati, Elizabeth; Thérien-Aubin, Héloïse; ...

    2016-08-24

    Patterning of colloidal particles with chemically or topographically distinct surface domains (patches) has attracted intense research interest. Surface-patterned particles act as colloidal analogues of atoms and molecules serve as model systems in studies of phase transitions in liquid systems, behave as ‘colloidal surfactants’ and function as templates for the synthesis of hybrid particles. The generation of micrometre- and submicrometre-sized patchy colloids is now efficient but surface patterning of inorganic colloidal nanoparticles with dimensions of the order of tens of nanometres is uncommon. Such nanoparticles exhibit size- and shape-dependent optical, electronic and magnetic properties, and their assemblies show new collective properties.more » At present, nanoparticle patterning is limited to the generation of two-patch nanoparticles and nanoparticles with surface ripples or a ‘raspberry’ surface morphology. We demonstrate nanoparticle surface patterning, which utilizes thermodynamically driven segregation of polymer ligands from a uniform polymer brush into surface-pinned micelles following a change in solvent quality. Patch formation is reversible but can be permanently preserved using a photocrosslinking step. The methodology offers the ability to control the dimensions of patches, their spatial distribution and the number of patches per nanoparticle, in agreement with a theoretical model. The versatility of the strategy is demonstrated by patterning nanoparticles with different dimensions, shapes and compositions, tethered with various types of polymers and subjected to different external stimuli. Furthermore, these patchy nanocolloids have potential applications in fundamental research, the self-assembly of nanomaterials, diagnostics, sensing and colloidal stabilization.« less

  20. Surface patterning of nanoparticles with polymer patches

    PubMed Central

    Choueiri, Rachelle M.; Galati, Elizabeth; Thérien-Aubin, Héloïse; Klinkova, Anna; Larin, Egor M.; Querejeta-Fernández, Ana; Han, Lili; Xin, Huolin L.; Gang, Oleg; Zhulina, Ekaterina B.; Rubinstein, Michael; Kumacheva, Eugenia

    2016-01-01

    Patterning of colloidal particles with chemically or topographically distinct surface domains (patches) has attracted intense research interest1–3. Surface-patterned particles act as colloidal analogues of atoms and molecules4,5, serve as model systems in studies of phase transitions in liquid systems6, behave as ‘colloidal surfactants’7 and function as templates for the synthesis of hybrid particles8. The generation of micrometre- and submicrometre-sized patchy colloids is now efficient9–11, but surface patterning of inorganic colloidal nanoparticles with dimensions of the order of tens of nanometres is uncommon. Such nanoparticles exhibit size- and shape-dependent optical, electronic and magnetic properties, and their assemblies show new collective properties12. At present, nanoparticle patterning is limited to the generation of two-patch nanoparticles13–15, and nanoparticles with surface ripples16 or a ‘raspberry’ surface morphology17. Here we demonstrate nanoparticle surface patterning, which utilizes thermodynamically driven segregation of polymer ligands from a uniform polymer brush into surface-pinned micelles following a change in solvent quality. Patch formation is reversible but can be permanently preserved using a photocrosslinking step. The methodology offers the ability to control the dimensions of patches, their spatial distribution and the number of patches per nanoparticle, in agreement with a theoretical model. The versatility of the strategy is demonstrated by patterning nanoparticles with different dimensions, shapes and compositions, tethered with various types of polymers and subjected to different external stimuli. These patchy nanocolloids have potential applications in fundamental research, the self-assembly of nanomaterials, diagnostics, sensing and colloidal stabilization. PMID:27556943

  1. Multi-Band Miniaturized Patch Antennas for a Compact, Shielded Microwave Breast Imaging Array.

    PubMed

    Aguilar, Suzette M; Al-Joumayly, Mudar A; Burfeindt, Matthew J; Behdad, Nader; Hagness, Susan C

    2013-12-18

    We present a comprehensive study of a class of multi-band miniaturized patch antennas designed for use in a 3D enclosed sensor array for microwave breast imaging. Miniaturization and multi-band operation are achieved by loading the antenna with non-radiating slots at strategic locations along the patch. This results in symmetric radiation patterns and similar radiation characteristics at all frequencies of operation. Prototypes were fabricated and tested in a biocompatible immersion medium. Excellent agreement was obtained between simulations and measurements. The trade-off between miniaturization and radiation efficiency within this class of patch antennas is explored via a numerical analysis of the effects of the location and number of slots, as well as the thickness and permittivity of the dielectric substrate, on the resonant frequencies and gain. Additionally, we compare 3D quantitative microwave breast imaging performance achieved with two different enclosed arrays of slot-loaded miniaturized patch antennas. Simulated array measurements were obtained for a 3D anatomically realistic numerical breast phantom. The reconstructed breast images generated from miniaturized patch array data suggest that, for the realistic noise power levels assumed in this study, the variations in gain observed across this class of multi-band patch antennas do not significantly impact the overall image quality. We conclude that these miniaturized antennas are promising candidates as compact array elements for shielded, multi-frequency microwave breast imaging systems.

  2. Predator-Prey Interactions Shape Thermal Patch Use in a Newt Larvae-Dragonfly Nymph Model

    PubMed Central

    Gvoždík, Lumír; Černická, Eva; Van Damme, Raoul

    2013-01-01

    Thermal quality and predation risk are considered important factors influencing habitat patch use in ectothermic prey. However, how the predator’s food requirement and the prey’s necessity to avoid predation interact with their respective thermoregulatory strategies remains poorly understood. The recently developed ‘thermal game model’ predicts that in the face of imminent predation, prey should divide their time equally among a range of thermal patches. In contrast, predators should concentrate their hunting activities towards warmer patches. In this study, we test these predictions in a laboratory setup and an artificial environment that mimics more natural conditions. In both cases, we scored thermal patch use of newt larvae (prey) and free-ranging dragonfly nymphs (predators). Similar effects were seen in both settings. The newt larvae spent less time in the warm patch if dragonfly nymphs were present. The patch use of the dragonfly nymphs did not change as a function of prey availability, even when the nymphs were starved prior to the experiment. Our behavioral observations partially corroborate predictions of the thermal game model. In line with asymmetric fitness pay-offs in predator-prey interactions (the ‘life-dinner’ principle), the prey’s thermal strategy is more sensitive to the presence of predators than vice versa. PMID:23755175

  3. Predator-prey interactions shape thermal patch use in a newt larvae-dragonfly nymph model.

    PubMed

    Gvoždík, Lumír; Černická, Eva; Van Damme, Raoul

    2014-01-01

    Thermal quality and predation risk are considered important factors influencing habitat patch use in ectothermic prey. However, how the predator's food requirement and the prey's necessity to avoid predation interact with their respective thermoregulatory strategies remains poorly understood. The recently developed 'thermal game model' predicts that in the face of imminent predation, prey should divide their time equally among a range of thermal patches. In contrast, predators should concentrate their hunting activities towards warmer patches. In this study, we test these predictions in a laboratory setup and an artificial environment that mimics more natural conditions. In both cases, we scored thermal patch use of newt larvae (prey) and free-ranging dragonfly nymphs (predators). Similar effects were seen in both settings. The newt larvae spent less time in the warm patch if dragonfly nymphs were present. The patch use of the dragonfly nymphs did not change as a function of prey availability, even when the nymphs were starved prior to the experiment. Our behavioral observations partially corroborate predictions of the thermal game model. In line with asymmetric fitness pay-offs in predator-prey interactions (the 'life-dinner' principle), the prey's thermal strategy is more sensitive to the presence of predators than vice versa.

  4. Effects of slits in a patch of omnidirectional Lamb-wave MPT on the transducer output

    NASA Astrophysics Data System (ADS)

    Kim, Kiyean; Lee, Hyung Jin; Lee, Joo Kyung; Kim, Yoon Young

    2016-03-01

    An omnidirectional Lamb-wave magnetostrictive patch transducer (MPT) uses a thin circular magnetostrictive patch excited by the axisymmetric turns of a plane coil placed over it. Since the dynamic magnetic field applied by the coil induces an eddy current only on the top surface due to the skin effect, the mechanical deformation in the patch is confined only near the surface, considerably limiting the transducer output power. This study shows that if a radial slit is introduced in the patch, the circular flow of the eddy current on the top surface only becomes broken, and thus the eddy current flows on both the top and bottom surfaces. As a consequence, there is a substantial increase in the dynamic magnetic field in the patch and, in turn, an increased transducer output power. Interestingly, the material type, either metallic or nonmetallic, of the test waveguide plate affects the magnitude of the eddy current near the bottom surface and the overall magnetic field. If the number of slits is over a certain number, say, 8, and the slits are symmetrically made in the patch, the omni-directivity of the resulting MPT is virtually ensured. Finally, the present findings are verified both numerically and experimentally.

  5. Patching vs Atropine to Treat Amblyopia in Children Aged 7 to 12 Years: A Randomized Trial

    PubMed Central

    2008-01-01

    Objective To compare patching with atropine eye drops in the treatment of moderate amblyopia (20/40 -20/100) in children age 7 to 12 years. Methods In a randomized multi-center clinical trial, 193 children with amblyopia were randomized to weekend atropine or patching 2 hours per day of the sound eye. Main Outcome Measure Masked assessment of amblyopic eye visual acuity using the EETDRS testing protocol at 17 weeks. Results At 17 weeks, visual acuity had improved from baseline by an average of 7.6 letters in the atropine group and 8.6 letters in the patching group. The mean difference (patching minus atropine) between groups adjusted for baseline acuity was 1.2 letters (ends of complementary 1-sided 95% confidence intervals for noninferiority = -0.7 and +3.1 letters). Based on the confidence intervals this difference met the pre-specified definition for equivalence (ends of confidence intervals <5 letters). Amblyopic eye visual acuity was 20/25 or better in 15 subjects (17%) in the atropine group and 20 subjects (24%) in the patching group (difference = 7%, 95% confidence interval = -3% to 17%). Conclusions Treatment with atropine or patching leads to similar degrees of improvement in 7 to 12 year old children with moderate amblyopia. About 1 in 5 achieves 20/25 or better visual acuity in the amblyopic eye. Application to Clinical Practice Treatment of older children with unilateral amblyopia. PMID:19064841

  6. Long-term stability of influenza vaccine in a dissolving microneedle patch.

    PubMed

    Mistilis, Matthew J; Joyce, Jessica C; Esser, E Stein; Skountzou, Ioanna; Compans, Richard W; Bommarius, Andreas S; Prausnitz, Mark R

    2017-04-01

    This study tested the hypothesis that optimized microneedle patch formulations can stabilize trivalent subunit influenza vaccine during long-term storage outside the cold chain and when exposed to potential stresses found during manufacturing and storage. Formulations containing combinations of trehalose/sucrose, sucrose/arginine, and arginine/heptagluconate were successful at retaining most or all vaccine activity during storage at 25 °C for up to 24 months as determined by ELISA assay. The best formulation of microneedle patches contained arginine/heptagluconate, which showed no significant loss of vaccine activity during the study. To validate these in vitro findings, mice were immunized using trivalent influenza vaccine stored in microneedle patches for more than 1 year at 25 °C, which elicited antibody titers greater than or equal to fresh liquid vaccine delivered by intradermal injection, indicating the retention of immunogenicity during storage. Finally, influenza vaccine in microneedle patches lost no significant activity during exposure to 60 °C for 4 months, multiple freeze-thaw cycles, or electron beam irradiation. We conclude that optimally formulated microneedle patches can retain influenza vaccine activity during extended storage outside the cold chain and during other environmental stresses, which suggests the possibility of microneedle patch storage on pharmacy shelves without refrigeration.

  7. Multi-Band Miniaturized Patch Antennas for a Compact, Shielded Microwave Breast Imaging Array

    PubMed Central

    Aguilar, Suzette M.; Al-Joumayly, Mudar A.; Burfeindt, Matthew J.; Behdad, Nader; Hagness, Susan C.

    2014-01-01

    We present a comprehensive study of a class of multi-band miniaturized patch antennas designed for use in a 3D enclosed sensor array for microwave breast imaging. Miniaturization and multi-band operation are achieved by loading the antenna with non-radiating slots at strategic locations along the patch. This results in symmetric radiation patterns and similar radiation characteristics at all frequencies of operation. Prototypes were fabricated and tested in a biocompatible immersion medium. Excellent agreement was obtained between simulations and measurements. The trade-off between miniaturization and radiation efficiency within this class of patch antennas is explored via a numerical analysis of the effects of the location and number of slots, as well as the thickness and permittivity of the dielectric substrate, on the resonant frequencies and gain. Additionally, we compare 3D quantitative microwave breast imaging performance achieved with two different enclosed arrays of slot-loaded miniaturized patch antennas. Simulated array measurements were obtained for a 3D anatomically realistic numerical breast phantom. The reconstructed breast images generated from miniaturized patch array data suggest that, for the realistic noise power levels assumed in this study, the variations in gain observed across this class of multi-band patch antennas do not significantly impact the overall image quality. We conclude that these miniaturized antennas are promising candidates as compact array elements for shielded, multi-frequency microwave breast imaging systems. PMID:25392561

  8. Patch occupancy, number of individuals and population density of the Marbled White in a changing agricultural landscape

    NASA Astrophysics Data System (ADS)

    Lenda, Magdalena; Skórka, Piotr

    2010-09-01

    Metapopulation theory predicts the occurrence of animals in habitat patches. In this paper, we tested predictions based on this theory, including effects of spatial autocorrelation, to describe factors affecting the presence, local number of individuals and density of the Marbled White butterfly Melanargia galathea in habitat patches spread across the agricultural landscape of southern Poland. This agricultural landscape has undergone significant changes in recent decades due to the country's political transformation and is currently characterized by a large proportion of fallow (abandoned) land. We compared 48 occupied habitat patches with 60 unoccupied ones. Positive spatial autocorrelation was found in the number and density of individuals in habitat patches. The probability of patch occupancy was higher for patches that were larger, had a higher proportion of edges, were located closer to the nearest neighbouring local population and to the nearest piece of fallow, contained a smaller area of cut grass, and also had more nectar resources. The number of Marbled Whites in habitat patches was positively related to the patch area, the distance to the nearest fallow and the abundance of nectar resources, but was negatively related to the density of shrubs. The density of individuals was positively related to abundance of flowers, proportion of edge in a patch and distance to the nearest fallow, but it was negatively related to patch area, vegetation height and grass cover. These results indicate that recent land-use changes in agricultural landscapes have had both positive and negative effects on the presence and local number of individuals and density of the Marbled White. These changes affect the metapopulation of the species through changes in habitat quality and landscape connectivity in the area surrounding habitat patches.

  9. Relationships of habitat patch size to predator community and survival of duck nests

    USGS Publications Warehouse

    Sovada, M.A.; Zicus, M.C.; Greenwood, R.J.; Rave, D.P.; Newton, W.E.; Woodward, R.O.; Beiser, J.A.

    2000-01-01

    We studied duck nest success and predator community composition in relation to size of discrete patches of nesting cover in the Prairie Pothole Region (PPR) of the United States in 1993-95. We focused on nests in uplands that were seeded to perennial grasses and forbs and enrolled in the Conservation Reserve Program (CRP) in Minnesota, North Dakota, and South Dakota. We estimated daily survival rates (DSRs) of upland duck nests and indices of activity for red foxes (Vulpes vulpes), coyotes (Canis latrans), American badgers (Taxidea taxus), striped skunks (Mephitis mephitis), and Franklin's ground squirrels (Spermophilus franklinii), and related these variables to habitat patch size. The effect of patch size (small vs. large) on estimated annual mean DSR was dependent on date of nest initiation (early vs. late) and year. Examination of within-year comparisons for early and late nests suggested that DSR was generally greater in larger habitat patches. Activity indices for the 5 mammalian nest predators were influenced differently by year, location, and patch size. Activity indices of the red fox were greatest in small patches. Coyote indices were the most inconsistent, demonstrating a year X location X patch size interaction. Activity indices of the striped skunk and American badger varied only among years. Franklin's ground squirrel indices were affected by study area location, with higher indices in the southeast than the northwest. Red fox activity was weakly correlated with that of the striped skunk and coyote. Although a positive relationship between habitat patch size and nest success probably exists, we believe the experiment to fully test this hypothesis will continue to be elusive.

  10. Emergent properties of patch shapes affect edge permeability to animals.

    PubMed

    Nams, Vilis O

    2011-01-01

    Animal travel between habitat patches affects populations, communities and ecosystems. There are three levels of organization of edge properties, and each of these can affect animals. At the lowest level are the different habitats on each side of an edge, then there is the edge itself, and finally, at the highest level of organization, is the geometry or structure of the edge. This study used computer simulations to (1) find out whether effects of edge shapes on animal behavior can arise as emergent properties solely due to reactions to edges in general, without the animals reacting to the shapes of the edges, and to (2) generate predictions to allow field and experimental studies to test mechanisms of edge shape response. Individual animals were modeled traveling inside a habitat patch that had different kinds of edge shapes (convex, concave and straight). When animals responded edges of patches, this created an emergent property of responding to the shape of the edge. The response was mostly to absolute width of the shapes, and not the narrowness of them. When animals were attracted to edges, then they tended to collect in convexities and disperse from concavities, and the opposite happened when animals avoided edges. Most of the responses occurred within a distance of 40% of the perceptual range from the tip of the shapes. Predictions were produced for directionality at various locations and combinations of treatments, to be used for testing edge behavior mechanisms. These results suggest that edge shapes tend to either concentrate or disperse animals, simply because the animals are either attracted to or avoid edges, with an effect as great as 3 times the normal density. Thus edge shape could affect processes like pollination, seed predation and dispersal and predator abundance.

  11. A Novel Miniaturization Technique of a Microstrip Patch Antenna using Patch Resonators

    NASA Astrophysics Data System (ADS)

    Kakita, Katsutoshi; Morita, Norihiko; Horii, Yasushi

    Microstrip patch antennas have been widely used in mobile and satellite communication systems due to their great advantages of low cost, low profile, lightweight and easy fabrication. However, the dimensions of a classical patch antenna are on the order of half a wavelength. This paper proposes a new approach to reduce the size of the antenna by embedding several patch resonators in an antenna substrate. Periodically installed resonators are expected to exhibit slow-wave effects. First of all, a microstrip delay line having a train of patch resonators in its substrate is demonstrated theoretically by the conventional FDTD method, and the slow-wave effect is discussed. Next, a 2-dimentional patch resonator array is applied to a microstrip patch antenna, and the effectiveness of the proposed structure is evaluated in the respect of antenna dimensions. Also, several experiments have been carried out to confirm the theoretical predictions. Using a prototype model fabricated on an LTCC substrate, the size reduction of more the 50% is attained.

  12. NORTHWEST OBLIQUE AERIAL VIEW OF FORT DELAWARE AND PEA PATCH ...

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

    NORTHWEST OBLIQUE AERIAL VIEW OF FORT DELAWARE AND PEA PATCH ISLAND. REMAINS OF SEA WALL VISIBLE IN FOREGROUND AND RIGHT OF IMAGE - Fort Delaware, Pea Patch Island, Delaware City, New Castle County, DE

  13. Performance Analysis of Coaxial Fed Stacked Patch Antennas

    NASA Astrophysics Data System (ADS)

    Jain, Satish K.; Jain, Shobha

    2014-01-01

    A performance analysis of coaxial fed stacked dual patch electromagnetic-coupled microstrip antenna useful for satellite communication working in X/Ku band is presented. A simplified structure of stacked dual patch antenna is proposed with adjustable foam-gap between patches. Few important geometrical parameters were chosen on which the performance of stacked dual patch antenna mainly depends. Dimension of lower square patch, upper square patch and height of foam-gap between two patches are the parameters, which were varied one by one keeping other parameters constant. The performance was observed through the reflection coefficient (dB) and smith chart impedance plot, obtained from the numerical simulator (IE3D) for the dual resonance frequency and bandwidth. Proposed geometry of stacked dual patch antenna was also analyzed with cavity model and artificial neural network modeling technique. Dual resonance frequencies and associated bandwidth were calculated through them and results were cross checked in the laboratory with a few experimental findings.

  14. [Responses of Caragana seed pests to host plant patch quality and patch pattern in desert regions of Ningxia, Northwest China].

    PubMed

    Zhang, Da-zhi; He, Da-han

    2011-07-01

    Taking the desert landscape in mid-eastern Ningxia of Northeast China as the background, eighteen patches of Caragana shrub lands (natural or manned) with the habitat types of manually-fixed sandy land, mobile sandy land, and silty-loam downland were selected as study sites to investigate the responses of three Caragana seed pest species (Kytorhinus immixtus, Etiella zinckenella, and Bruchophagus neocaraganae) to the host plant patch quality, patch area, and patch spatial pattern. The damaged rate of host plant by the pests had close relations to the patch quality, patch pattern, and the transferring capability of the pests. The responses of the pests to patch quality were affected by patch scale, and among the three habitat types, manually-fixed sandy land had the highest damaged rate, followed by mobile sandy land, and silty-loam downland, with significant differences among them (P<0.05). In small scale patch pattern, there existed definite correlations between the pest number and the patch area and its fragmentation degree. The decrease of patch area and the increase of the fragmentation degree reduced the damage rate of high transferring capability Etiella zinckenella (r = 0.365), but had less effects on low transferring capability K. immixtus (r = 0.160) and B. neocaraganae (r = 0.193). The strength of patch edge effect and the mutual complement of the resources around patches had positive effects on the population density of the pests.

  15. Corridor Length and Patch Colonization by a Butterfly, Junonia coenia

    SciTech Connect

    Haddad, N.

    1999-01-22

    Study hypothesized that corridors increase patch colonization by Junonia coenia regardless of insects initial distance from patch, as the butterfly is known to move between patches preferentially through corridors. Neither corridor nor distance had significant effect on patch colonization, but significant interaction between presence or absence of corridors and distance. One critical factor is interpatch distance which may determine the relative effectiveness of corridors and other landscape configurations.

  16. Ceramic Paste for Patching High-Temperature Insulation

    NASA Technical Reports Server (NTRS)

    Adam, Steven J.; Tompkins, James V.; Toombs, Gordon R.; Hogensen, Pete; Soden, Douglas G.

    2007-01-01

    A ceramic paste that can be applied relatively easily, either by itself or in combination with one or more layer(s) of high-temperature ceramic fabrics, such as silicon carbide or zirconia, has been invented as a means of patching cracks or holes in the reinforced carbon-carbon forward surfaces of a space shuttle in orbit before returning to Earth. The paste or the paste/fabric combination could also be used to repair rocket-motor combustion chambers, and could be used on Earth to patch similar high-temperature structures. The specified chemical composition of the paste admits of a number of variations, and the exact proportions of its constituents are proprietary. In general, the paste consists of (1) silicon carbide, possibly with addition of (2) hafnium carbide, zirconium carbide, zirconium boride, silicon tetraboride, silicon hexaboride, or other metal carbides or oxides blended with (3) a silazane-based polymer. Because the paste is viscous and sticky at normal terrestrial and outer-space ambient temperatures, high-temperature ceramic fabrics such as silicon carbide or zirconia fabric impregnated with the paste (or the paste alone) sticks to the damaged surface to which it is applied. Once the patch has been applied, it is smoothed to minimize edge steps as required [forward-facing edge steps must be < or equal to 0.030 in. (< or equal to 0.76 mm) in the original intended space-shuttle application]. The patch is then heated to a curing temperature thereby converting it from a flexible material to a hard, tough material. The curing temperature is 375 to 450 F (approx.190 to 230 C). In torch tests and arc-jet tests, the cured paste was found to be capable of withstanding a temperature of 3,500 F (approx. 1,900 C) for 15 minutes. As such, the material appears to satisfy the requirement, in the original space-shuttle application, to withstand re-entry temperatures of approx.3,000 F (approx. 1,600 C).

  17. Novel Metamaterials for Patch Antennas Applications

    NASA Astrophysics Data System (ADS)

    Zervos, Theodore; Lazarakis, Fotis; Alexandridis, Antonis; Dangakis, Kostas; Stamopoulos, Dimosthenis; Pissas, Michalis

    In this paper we introduce the incorporation of magneto-electric materials into antenna design and the potential of controlling the behavior of the antenna by means of an external magnetic field. After an intensive study of magneto-electric material properties, a ferrimagnetic compound called Yttrium Iron Garnet (YIG) was found to be the best candidate for the novel antenna design. We provide a metamaterial patch antenna design where a part of the substrate is replaced by the YIG compound. After several design modifications the final model includes a circular-shaped YIG substrate just under the metallic patch and offers sufficient performance in terms of resonance, bandwidth and radiation efficiency. Additionally, in the presence of an external magnetic field the polarization becomes elliptical and the sense of the polarization (left or right) can be controlled through the direction of the magnetic field. That latter characteristic confirms the metamaterial-nature of the antenna.

  18. Mesh saliency with adaptive local patches

    NASA Astrophysics Data System (ADS)

    Nouri, Anass; Charrier, Christophe; Lézoray, Olivier

    2015-03-01

    3D object shapes (represented by meshes) include both areas that attract the visual attention of human observers and others less or not attractive at all. This visual attention depends on the degree of saliency exposed by these areas. In this paper, we propose a technique for detecting salient regions in meshes. To do so, we define a local surface descriptor based on local patches of adaptive size and filled with a local height field. The saliency of mesh vertices is then defined as its degree measure with edges weights computed from adaptive patch similarities. Our approach is compared to the state-of-the-art and presents competitive results. A study evaluating the influence of the parameters establishing this approach is also carried out. The strength and the stability of our approach with respect to noise and simplification are also studied.

  19. Compressive strain measurement using RFID patch antenna sensors

    NASA Astrophysics Data System (ADS)

    Cho, Chunhee; Yi, Xiaohua; Wang, Yang; Tentzeris, Manos M.; Leon, Roberto T.

    2014-04-01

    In this research, two radiofrequency identification (RFID) antenna sensor designs are tested for compressive strain measurement. The first design is a passive (battery-free) folded patch antenna sensor with a planar dimension of 61mm × 69mm. The second design is a slotted patch antenna sensor, whose dimension is reduced to 48mm × 44mm by introducing slots on antenna conducting layer to detour surface current path. A three-point bending setup is fabricated to apply compression on a tapered aluminum specimen mounted with an antenna sensor. Mechanics-electromagnetics coupled simulation shows that the antenna resonance frequency shifts when each antenna sensor is under compressive strain. Extensive compression tests are conducted to verify the strain sensing performance of the two sensors. Experimental results confirm that the resonance frequency of each antenna sensor increases in an approximately linear relationship with respect to compressive strain. The compressive strain sensing performance of the two RFID antenna sensors, including strain sensitivity and determination coefficient, is evaluated based on the experimental data.

  20. Patch Finder Plus (PFplus): a web server for extracting and displaying positive electrostatic patches on protein surfaces.

    PubMed

    Shazman, Shula; Celniker, Gershon; Haber, Omer; Glaser, Fabian; Mandel-Gutfreund, Yael

    2007-07-01

    Positively charged electrostatic patches on protein surfaces are usually indicative of nucleic acid binding interfaces. Interestingly, many proteins which are not involved in nucleic acid binding possess large positive patches on their surface as well. In some cases, the positive patches on the protein are related to other functional properties of the protein family. PatchFinderPlus (PFplus) http://pfp.technion.ac.il is a web-based tool for extracting and displaying continuous electrostatic positive patches on protein surfaces. The input required for PFplus is either a four letter PDB code or a protein coordinate file in PDB format, provided by the user. PFplus computes the continuum electrostatics potential and extracts the largest positive patch for each protein chain in the PDB file. The server provides an output file in PDB format including a list of the patch residues. In addition, the largest positive patch is displayed on the server by a graphical viewer (Jmol), using a simple color coding.

  1. Optimal patch code design via device characterization

    NASA Astrophysics Data System (ADS)

    Wu, Wencheng; Dalal, Edul N.

    2012-01-01

    In many color measurement applications, such as those for color calibration and profiling, "patch code" has been used successfully for job identification and automation to reduce operator errors. A patch code is similar to a barcode, but is intended primarily for use in measurement devices that cannot read barcodes due to limited spatial resolution, such as spectrophotometers. There is an inherent tradeoff between decoding robustness and the number of code levels available for encoding. Previous methods have attempted to address this tradeoff, but those solutions have been sub-optimal. In this paper, we propose a method to design optimal patch codes via device characterization. The tradeoff between decoding robustness and the number of available code levels is optimized in terms of printing and measurement efforts, and decoding robustness against noises from the printing and measurement devices. Effort is drastically reduced relative to previous methods because print-and-measure is minimized through modeling and the use of existing printer profiles. Decoding robustness is improved by distributing the code levels in CIE Lab space rather than in CMYK space.

  2. Nanowired three-dimensional cardiac patches

    NASA Astrophysics Data System (ADS)

    Dvir, Tal; Timko, Brian P.; Brigham, Mark D.; Naik, Shreesh R.; Karajanagi, Sandeep S.; Levy, Oren; Jin, Hongwei; Parker, Kevin K.; Langer, Robert; Kohane, Daniel S.

    2011-11-01

    Engineered cardiac patches for treating damaged heart tissues after a heart attack are normally produced by seeding heart cells within three-dimensional porous biomaterial scaffolds. These biomaterials, which are usually made of either biological polymers such as alginate or synthetic polymers such as poly(lactic acid) (PLA), help cells organize into functioning tissues, but poor conductivity of these materials limits the ability of the patch to contract strongly as a unit. Here, we show that incorporating gold nanowires within alginate scaffolds can bridge the electrically resistant pore walls of alginate and improve electrical communication between adjacent cardiac cells. Tissues grown on these composite matrices were thicker and better aligned than those grown on pristine alginate and when electrically stimulated, the cells in these tissues contracted synchronously. Furthermore, higher levels of the proteins involved in muscle contraction and electrical coupling are detected in the composite matrices. It is expected that the integration of conducting nanowires within three-dimensional scaffolds may improve the therapeutic value of current cardiac patches.

  3. Modular assembly of thick multifunctional cardiac patches

    PubMed Central

    Fleischer, Sharon; Shapira, Assaf; Feiner, Ron; Dvir, Tal

    2017-01-01

    In cardiac tissue engineering cells are seeded within porous biomaterial scaffolds to create functional cardiac patches. Here, we report on a bottom-up approach to assemble a modular tissue consisting of multiple layers with distinct structures and functions. Albumin electrospun fiber scaffolds were laser-patterned to create microgrooves for engineering aligned cardiac tissues exhibiting anisotropic electrical signal propagation. Microchannels were patterned within the scaffolds and seeded with endothelial cells to form closed lumens. Moreover, cage-like structures were patterned within the scaffolds and accommodated poly(lactic-co-glycolic acid) (PLGA) microparticulate systems that controlled the release of VEGF, which promotes vascularization, or dexamethasone, an anti-inflammatory agent. The structure, morphology, and function of each layer were characterized, and the tissue layers were grown separately in their optimal conditions. Before transplantation the tissue and microparticulate layers were integrated by an ECM-based biological glue to form thick 3D cardiac patches. Finally, the patches were transplanted in rats, and their vascularization was assessed. Because of the simple modularity of this approach, we believe that it could be used in the future to assemble other multicellular, thick, 3D, functional tissues. PMID:28167795

  4. Carbon Nanotube Based Sensor to Monitor Crack Growth in Cracked Aluminum Structures Underneath Composite Patching

    NASA Astrophysics Data System (ADS)

    Olson, T. M.; Kwon, Y. W.; Hart, D. C.; Loup, D. C.; Rasmussen, E. A.

    2015-10-01

    The paper investigates a carbon nanotube-based sensor to detect crack propagation in aluminum structures underneath composite patching. Initial tests are conducted to determine the correct procedure and materials to properly fabricate a carbon nanotube (CNT) based sensor, which is then placed in between a composite patch and the aluminum structure. The CNTs have been utilized as sensors in previous studies but only for sensing crack propagation within the composite itself. This study focuses on crack propagation in the base material and is not concerned with the composite. In this application, the composite is only a patch and can be replaced if damaged. The study conducts both tension and fatigue testing to determine the usefulness of the CNT sensor. The CNT sensor is shown to be effective in giving an indication of the crack propagation in the aluminum. Correlation is done between the crack propagation length and the increase in electrical resistance in the CNT sensor under tensile and cyclic loading, respectively.

  5. Experimental Fatigue Study of Composite Patch Repaired Steel Plates with Cracks

    NASA Astrophysics Data System (ADS)

    Karatzas, Vasileios A.; Kotsidis, Elias A.; Tsouvalis, Nicholas G.

    2015-10-01

    Cracks are among the most commonly encountered defects in metallic structures operating at sea. Composite patch repairing is a repair method which is gaining popularity as it counters most of the problems faced by conventional renewal repairs. Extensive studies can be found in the literature addressing the efficiency of this novel repair method using techniques which meet higher performance and monitoring standards than these commonly found in naval applications. In this work the efficiency of practices widely used in the ship repair industry for the implementation of composite patch repairing is addressed. To this end, steel plates repaired with composite patches were tested under fatigue loading. The composite patches consisted of carbon fibers in epoxy matrix and were directly laminated to the steel surface using the vacuum infusion method. Two different surface preparation methods, namely grit-blasting and mechanical treatment with the use of a needle gun were studied. In addition, in order to account for the harsh environmental conditions during the operating life of the structure and to study its effect on the repair, two different aging scenarios were considered. Non-destructive evaluation of the patches was performed so as to assess the quality of the repair, and the evolution of debonding during testing.

  6. A hospital cost analysis of a fibrin sealant patch in soft tissue and hepatic surgical bleeding

    PubMed Central

    Corral, Mitra; Ferko, Nicole; Hogan, Andrew; Hollmann, Sarah S; Gangoli, Gaurav; Jamous, Nadine; Batiller, Jonathan; Kocharian, Richard

    2016-01-01

    Background Despite hemostat use, uncontrolled surgical bleeding is prevalent. Drawbacks of current hemostats include limitations with efficacy on first attempt and suboptimal ease-of-use. Evarrest® is a novel fibrin sealant patch that has demonstrated high hemostatic efficacy compared with standard of care across bleeding severities. The objective of this study was to conduct a hospital cost analysis of the fibrin sealant patch versus standard of care in soft tissue and hepatic surgical bleeding. Methods The analysis quantified the 30-day costs of each comparator from a hospital perspective. Published US unit costs were applied to resource use (ie, initial treatment, retreatment, operating time, hospitalization, transfusion, and ventilator) reported in four trials. A “surgical” analysis included resources clinically related to the hemostatic benefit of the fibrin sealant patch, whereas a “hospital” analysis included all resources reported in the trials. An exploratory subgroup analysis focused solely on coagulopathic patients defined by abnormal blood test results. Results The surgical analysis predicted cost savings of $54 per patient with the fibrin sealant patch compared with standard of care (net cost impact: −$54 per patient; sensitivity range: −$1,320 to $1,213). The hospital analysis predicted further cost savings with the fibrin sealant patch (net cost impact of −$2,846 per patient; sensitivity range: −$1,483 to −$5,575). Subgroup analyses suggest that the fibrin sealant patch may provide dramatic cost savings in the coagulopathic subgroup of $3,233 (surgical) and $9,287 (hospital) per patient. Results were most sensitive to operating time and product units. Conclusion In soft tissue and hepatic problematic surgical bleeding, the fibrin sealant patch may result in important hospital cost savings. PMID:27703386

  7. Computer-aided patch planning for treatment of complex coarctation of the aorta

    NASA Astrophysics Data System (ADS)

    Rietdorf, Urte; Riesenkampff, Eugénie; Kuehne, Titus; Huebler, Michael; Meinzer, Hans-Peter; Wolf, Ivo

    2009-02-01

    Between five and eight percent of all children born with congenitally malformed hearts suffer from coarctations of the aorta. Some severe coarctations can only be treated by surgical repair. Untreated, this defect can cause serious damage to organ development or even lead to death. Patch repair requires open surgery. It can affect patients of any age: newborns with severe coarctation and/or hypoplastic aortic arch as well as older patients with late diagnosis of coarctation of the aorta. Another patient group are patients of varying age with re-coarctation of the aorta or hypoplastic aortic arch after surgical and/or interventional repair. If anatomy is complex and interventional treatment by catheterization, balloon angioplasty or stent placement is not possible, surgery is indicated. The choice of type of surgery depends not only on the given anatomy but also on the experience the surgical team has with each method. One surgical approach is patch repair. A patch of a suitable shape and size is sewed into the aorta to expand the aortic lumen at the site of coarctation. At present, the shape and size of the patch are estimated intra-operatively by the surgeon. We have developed a software application that allows planning of the patch pre-operatively on the basis of magnetic resonance angiographic data. The application determines the diameter of the coarctation and/or hypoplastic segment and constructs a patch proposal by calculating the difference to the normal vessel diameter pre-operatively. Evaluation of MR angiographic datasets from 12 test patients with different kinds of aortic arch stenosis shows a divergence of only (1.5+/-1.2) mm in coarctation diameters between manual segmentations and our approach, with comparable time expenditure. Following this proposal the patch can be prepared and adapted to the patient's anatomy pre-operatively. Ideally, this leads to shorter operation times and a better long-term outcome with a reduced rate of residual stenosis and

  8. A Latent Source Model for Patch-Based Image Segmentation.

    PubMed

    Chen, George H; Shah, Devavrat; Golland, Polina

    2015-10-01

    Despite the popularity and empirical success of patch-based nearest-neighbor and weighted majority voting approaches to medical image segmentation, there has been no theoretical development on when, why, and how well these nonparametric methods work. We bridge this gap by providing a theoretical performance guarantee for nearest-neighbor and weighted majority voting segmentation under a new probabilistic model for patch-based image segmentation. Our analysis relies on a new local property for how similar nearby patches are, and fuses existing lines of work on modeling natural imagery patches and theory for nonparametric classification. We use the model to derive a new patch-based segmentation algorithm that iterates between inferring local label patches and merging these local segmentations to produce a globally consistent image segmentation. Many existing patch-based algorithms arise as special cases of the new algorithm.

  9. Movement of patches during thermoforming: Experiment and simulation

    NASA Astrophysics Data System (ADS)

    Schell, J. S. U.; Amory, L.; Guillon, D.

    2016-10-01

    The application of local reinforcement like uni-directional patches can locally increase the strength of composite parts without adding much weight. During design through structural analysis, shape and position of local reinforcement can easily be determined. In the thermoforming process, patches can be integrated into the ply-stack by preassembling. During forming, these patches can move and change their position reducing the structural effect of the patch. The movement of patches has been investigated experimentally. Key factors that influence this movement are orientation, size, position in the pile and slope of the mold. The forming process is simulated using HYPERFORM. The results show that this complex process needs special models which can be computationally intensive. In this work, we model the movement of patches and compare with experiments. The final goal is to have a reasonable predictive capability for movement of patches and design the process to minimize it.

  10. A MULTI-PATCH MALARIA MODEL WITH LOGISTIC GROWTH POPULATIONS*

    PubMed Central

    GAO, DAOZHOU; RUAN, SHIGUI

    2013-01-01

    In this paper, we propose a multi-patch model to study the effects of population dispersal on the spatial spread of malaria between patches. The basic reproduction number R0 is derived and it is shown that the disease-free equilibrium is locally asymptotically stable if R0<1 and unstable if R0>1. Bounds on the disease-free equilibrium and R0 are given. A sufficient condition for the existence of an endemic equilibrium when R0>1 is obtained. For the two-patch submodel, the dependence of R0 on the movement of exposed, infectious, and recovered humans between the two patches is investigated. Numerical simulations indicate that travel can help the disease to become endemic in both patches, even though the disease dies out in each isolated patch. However, if travel rates are continuously increased, the disease may die out again in both patches. PMID:23723531

  11. Analysis of habitat selection studies with multiple patches within cover types

    USGS Publications Warehouse

    Otis, D.L.

    1997-01-01

    Current statistical methods are inadequate for evaluation of the relation between spatial pattern of the landscape and observed patterns of habitat use by individuals or populations. For example, traditional habitat selection analysis methods do not use information about the size and distribution of the several patches of each cover type that may exist within the study area. Statistical tests are presented for hypotheses about disproportional use of cover types and patches within cover types. These tests require that use of individual patches is recorded, as well as the size of individual patches. Different designs are considered in which there are (1) single or multiple samples of use, and (2) equal or unequal habitat availability. Formulas for calculating Type II statistical errors of the tests are presented and Monte Carlo simulation is used to assess the accuracy of the formulas and to check the Type I error rates of the proposed test statistics. With adequate sample sizes, Type II error formulas can be a useful tool for planning of habitat selection studies. An example analysis is presented of a hypothetical study of habitat selection by ring-necked pheasants (Phasianus colchicus) in a Midwestern landscape. The proposed tests also represent a contribution toward bringing together concepts of landscape ecology and wildlife habitat selection.

  12. Deep patch technique for landslide repair. Final report

    SciTech Connect

    Helwany, B.M.

    1994-10-01

    The report describes the laboratory testing of the `USFS deep patch` technique and a CTI modification of this technique for repairing landslides with geosynthetic reinforcement. The technique involves replacing sections of roadway lost due to landslides on top of a geosynthetically-reinforced embankment. The CTI modification involves replacing the reinforced slope with a geosynthetically-reinforced retaining wall with a truncated base. Both techniques rely on the cantilevering ability of the reinforced mass to limit the load on the foundation with a high slide potential. The tests with road base showed that (1) both the USFS and CTI repair reduced effectively the adverse effects of local landsliding on the highway pavement by preventing crack propagation; (2) the USFS repair increased the stability of the repaired slope, which was in progressive failure, by reducing the stresses exerted on it; and (3) the CTI repair produced substantially greater stresses on its foundation due to the truncated base of the reinforced mass.

  13. The time dependence of reversed archeomagnetic flux patches

    NASA Astrophysics Data System (ADS)

    Terra-Nova, Filipe; Amit, Hagay; Hartmann, Gelvam A.; Trindade, Ricardo I. F.

    2016-04-01

    Archeomagnetic field models may provide important insights to the geodynamo. Here we investigate the existence and mobility of reversed flux patches (RFPs) in archeomagnetic field model CALS3k.4b of Korte and Constable (2011; PEPI, 188, 247-259). We introduce topological algorithms to define, identify and track RPFs. In addition, we explore the relations between RFPs and dipole changes, and apply robustness tests to the RFPs. In contrast to previous definitions, patches that reside on the geographic equator are adequately identified based on our RFPs definition that takes the magnetic equator as a reference. Most RFPs exhibit a westward drift and migrate towards higher latitudes. Undulations of the magnetic equator and RFPs oppose the axial dipole moment (ADM). Filtered models show a tracking behaviour similar to the non-filtered model, and surprisingly new RFPs occasionally emerge. The advection and diffusion of RFPs have worked in unison to yield the decrease of the ADM at recent times. The absence of RFPs in the period 550-1440 AD is related to a low in intermediate degrees of the geomagnetic power spectrum. We thus hypothesize that the RFPs are strongly dependent on intermediate spherical harmonic degrees 4 and above. Comparison of tracking of RFPs among various archeomagnetic field models was also performed and gives more complex results.

  14. The time dependence of reversed archeomagnetic flux patches

    NASA Astrophysics Data System (ADS)

    Terra-Nova, Filipe; Amit, Hagay; Hartmann, Gelvam A.; Trindade, Ricardo I. F.

    2015-02-01

    Archeomagnetic field models may provide important insights to the geodynamo. Here we investigate the existence and mobility of reversed flux patches (RFPs) in an archeomagnetic field model. We introduce topological algorithms to define, identify, and track RFPs. In addition, we explore the relations between RFPs and dipole changes and apply robustness tests to the RFPs. In contrast to previous definitions, patches that reside on the geographic equator are adequately identified based on our RFPs definition. Most RFPs exhibit a westward drift and migrate toward higher latitudes. Undulations of the magnetic equator and RFPs oppose the axial dipole moment (ADM). Filtered models show a tracking behavior similar to the nonfiltered model, and surprisingly new RFPs occasionally emerge. The advection and diffusion of RFPs have worked in unison to yield the decrease of the ADM at recent times. The absence of RFPs in the period 550-1440 A.D. is related to a low in intermediate degrees of the geomagnetic power spectrum. We thus hypothesize that the RFPs are strongly dependent on intermediate spherical harmonic degrees 4 and above.

  15. Speed estimates from grating patches are not contrast-normalized

    NASA Technical Reports Server (NTRS)

    Thompson, P.; Stone, L. S.; Swash, S.

    1996-01-01

    We have previously shown that the perceived speed of a moving grating depends upon its contrast, with lower-contrast patterns appearing to move more slowly than otherwise identical higher-contrast patterns. To explain this finding while remaining consistent with the findings of McKee, Silverman and Nakayama [(1986) Vision Research, 26, 609-619], we proposed that this misperception might arise from a modified version of the contrast-normalization procedure, envisaged by Adelson and Bergen [(1986) The extraction of spatio-temporal energy in human and machine vision (pp. 135-139). Charleston, S.C.: IEEE Computer Society] as a necessary second stage of motion-energy models of human motion processing. Specifically, our previous results might be explained if the two gratings to be compared interfered with each other's normalization. To test this hypothesis we performed two experiments. Experiment 1 demonstrates that the contrast effects persist even when two grating patches to be compared are presented up to 5 sec apart so that they would not be expected to bias each other's normalization. Experiment 2 shows that the contrast effects are unchanged when the two grating patches are surrounded by a range of patterns whose contrast would be expected to interfere with any normalization process. These two results allow the rejection of the contrast-normalized motion-energy hypothesis as an explanation of human speed perception. We discuss the consequences of these results on models of speed processing in the human visual system.

  16. Effect of stiffness and thickness ratio of host plate and piezoelectric patches on reduction of the stress concentration factor

    NASA Astrophysics Data System (ADS)

    Fesharaki, Javad Jafari; Madani, Seyed Ghasem; Golabi, Sa'id

    2016-09-01

    This paper focuses on the effects of stiffness ratio and thickness ratio on reducing stress concentration factor using piezoelectric patches in a rectangular plate with a hole, as a classical shape. Various locations of actuators and induction of positive/negative strains into the host plate are investigated and the best location of patches is presented. The study investigated the ratio effects and piezoelectric patches bounded on a rectangular host plate having various thicknesses and materials. Results show that the best position of actuators varies based on values of thickness and stiffness ratios of the host plate and piezoelectric patches. Also, the location of maximum stress concentration is transmitted from top and bottom of the hole to another point around the edge by changing the location of the piezoelectric actuators. To verify the results, some experimental tests are applied. The results show good agreement between the finite element analysis and experimental tests.

  17. Wideband Patch Antenna for Land based Vehicles

    NASA Astrophysics Data System (ADS)

    Gangwar, R. P. S.; Dutt, Sanjay

    2016-12-01

    In this paper, an irregular pentagon shaped patch antenna has been presented. The proposed antenna operates over a wide band in frequency range from 12 to 26 GHz with VSWR < 2. It has a partial ground plane with two-inverted L and one I shaped slots in the radiation patch to attain wide bandwidth. The antenna consists of FR4 epoxy as a dielectric substrate with dielectric constant 4.4 and loss tangent 0.002. The size of the antenna is 30 × 30 × 1.57 mm3 and is fed by the microstrip line. The size of the fabricated proposed antenna is smaller than that of the antenna under reference (elliptical radiating patch with defected ground plane). The simulation has been done using high frequency structure simulator (HFSS) which is a finite element method (FEM) based tool. The proposed antenna exhibits the return loss of 21.85, 28.03 and 29.14 dB and gain of 6.6, 5.67 and 7.0 dB at resonant frequencies 16.7, 19.00 and 21.4 GHz, respectively. The bandwidth of the antenna is 10 GHz with normalized radiation efficiencies of 65, 69 and 70 % at corresponding resonant frequencies. The measured results of the fabricated proposed antenna have been compared with the simulated results and there has been a close agreement between both the results. Also the simulated results of the proposed antenna have been compared with the antenna under reference and it is found that the performance of the proposed antenna is far better. The proposed antenna can be used for land based vehicles in both Ku-band (12-18 GHz) and K-band (18-26 GHz).

  18. Robust Nonnegative Patch Alignment for Dimensionality Reduction.

    PubMed

    You, Xinge; Ou, Weihua; Chen, Chun Lung Philip; Li, Qiang; Zhu, Ziqi; Tang, Yuanyan

    2015-11-01

    Dimensionality reduction is an important method to analyze high-dimensional data and has many applications in pattern recognition and computer vision. In this paper, we propose a robust nonnegative patch alignment for dimensionality reduction, which includes a reconstruction error term and a whole alignment term. We use correntropy-induced metric to measure the reconstruction error, in which the weight is learned adaptively for each entry. For the whole alignment, we propose locality-preserving robust nonnegative patch alignment (LP-RNA) and sparsity-preserviing robust nonnegative patch alignment (SP-RNA), which are unsupervised and supervised, respectively. In the LP-RNA, we propose a locally sparse graph to encode the local geometric structure of the manifold embedded in high-dimensional space. In particular, we select large p -nearest neighbors for each sample, then obtain the sparse representation with respect to these neighbors. The sparse representation is used to build a graph, which simultaneously enjoys locality, sparseness, and robustness. In the SP-RNA, we simultaneously use local geometric structure and discriminative information, in which the sparse reconstruction coefficient is used to characterize the local geometric structure and weighted distance is used to measure the separability of different classes. For the induced nonconvex objective function, we formulate it into a weighted nonnegative matrix factorization based on half-quadratic optimization. We propose a multiplicative update rule to solve this function and show that the objective function converges to a local optimum. Several experimental results on synthetic and real data sets demonstrate that the learned representation is more discriminative and robust than most existing dimensionality reduction methods.

  19. Preparation of a ligustrazine ethosome patch and its evaluation in vitro and in vivo

    PubMed Central

    Liu, Xingyan; Liu, Hong; Liu, Jianqiang; He, Zhiwei; Ding, Congcong; Huang, Guoliang; Zhou, Weihua; Zhou, Leshan

    2011-01-01

    Background The purpose of this study was to develop a transdermal ligustrazine patch containing a stable formulation and with good entrapment efficiency, release rate, and transdermal absorption. Methods Ligustrazine ethosomes were prepared by ethanol injection-sonication, with entrapment efficiency as an indicator. Using acrylic resin as the primary constituent, the ligustrazine ethosome patch was prepared by adding succinic acid as a crosslinking agent and triethyl citrate as a plasticizer. In vitro release and transdermal permeation studies were carried out. Finally, a pharmacokinetic study was carried out in rats to explore relative bioavailability. The formulations of ligustrazine ethosome were 1% (w/v) phospholipid, 0.4% (w/v) cholesterol, and 45% (v/v) ethanol. Results Ligustrazine ethosomes were obtained with an average particle size of 78.71 ± 1.23 nm and an average entrapment efficiency of 86.42% ± 1.50%. In vitro transdermal testing of the ligustrazine ethosome patches showed that the cumulative 24-hour amount of ligustrazine was up to 183 ± 18 μg/cm2. The pharmacokinetic results revealed that the relative bioavailability was 209.45%. Conclusion Compared with conventional ligustrazine administration, ligustrazine ethosome patches could promote better drug absorption and increase bioavailability. This study demonstrates that the transdermal action of the ligustrazine ethosome patch was comparatively good. PMID:21499422

  20. Direct transfer trajectory design options for interplanetary orbiter missions using an iterative patched conic method

    NASA Astrophysics Data System (ADS)

    Parvathi, S. P.; Ramanan, R. V.

    2017-04-01

    In a direct interplanetary transfer, the spacecraft moves from a parking orbit of the departure planet to a parking orbit of the arrival planet. The transfer trajectory must be designed such that the specified arrival parking orbit conditions are achieved. For a fixed departure epoch and flight duration, there are four distinct transfer trajectory design options in a direct transfer. The conventional patched conic method, the most widely used analytical trajectory design method, does not identify these design options. An iterative patched conic method that identifies these distinct design options is developed and presented in this paper. This method involves two iterative processes: (i) iteration on the hyperbolic orbit characteristics using an analytical tuning strategy to achieve the hyperbolic excess velocity vector at the patch point, (ii) iteration on the patch points at the sphere of influence. The performance of the proposed method is compared with the conventional and V-infinity tuned patched conic methods. A design analysis tool, based on the proposed method, is developed and tested in various orbiter mission scenarios.

  1. Disruptive coloration in woodland camouflage: evaluation of camouflage effectiveness due to minor disruptive patches

    NASA Astrophysics Data System (ADS)

    Selj, Gorm K.; Heinrich, Daniela H.

    2016-10-01

    We present results from an observer based photosimulation study of generic camouflage patterns, intended for military uniforms, where three near-identical patterns have been compared. All the patterns were prepared with similar effective color, but were different in how the individual pattern patches were distributed throughout the target. We did this in order to test if high contrast (black) patches along the outline of the target would enhance the survivability when exposed to human observers. In the recent years it has been shown that disruptive coloration in the form of high contrast patches are capable of disturbing an observer by creating false edges of the target and consequently enhance target survivability. This effect has been shown in different forms in the Animal Kingdom, but not to the same extent in camouflaged military targets. The three patterns in this study were i) with no disruptive preference, ii) with a disruptive patch along the outline of the head and iii) with a disruptive patch on the outline of one of the shoulders. We used a high number of human observers to assess the three targets in 16 natural (woodland) backgrounds by showing images of one of the targets at the time on a high definition pc screen. We found that the two patterns that were thought to have a minor disruptive preference to the remaining pattern were more difficult to detect in some (though not all) of the 16 scenes and were also better in overall performance when all the scenes were accounted for.

  2. Patch-clamp array with on-chip electronics, optics, flow control and mechanical actuation.

    SciTech Connect

    James, Conrad D.; Okandan, Murat; Draper, Bruce Leroy; Mani, Seethambal S.

    2003-07-01

    Fast and quantitative analysis of cellular activity, signaling and responses to external stimuli is a crucial capability and it has been the goal of several projects focusing on patch clamp measurements. To provide the maximum functionality and measurement options, we have developed a patch clamp array device that incorporates on-chip electronics, mechanical, optical and microfluidic coupling as well as cell localization through fluid flow. The preliminary design, which integrated microfluidics, electrodes and optical access, was fabricated and tested. In addition, new designs which further combine mechanical actuation, on-chip electronics and various electrode materials with the previous designs are currently being fabricated.

  3. ATRIS Seafloor Images – West Turtle Shoal Patch Reef, Rawa Patch Reef, Dustan Rocks Patch Reef, and Thor Patch Reef, Florida, 2011

    USGS Publications Warehouse

    Zawada, David G.; Ruzicka, Rob; Colella, Michael A.; Resnick, Jessica

    2016-01-01

    The U.S. Geological Survey St. Petersburg Coastal and Marine Science Center developed the Along-Track Reef Imaging System (ATRIS) in order to capture high-resolution, geo-located images of the seafloor. The images in this data release were collected September 29-30, 2011 at West Turtle Shoal, Rawa, Dustan Rocks, and Thor patch reefs near Marathon, Florida. The transects below show the path of image collection.For further information regarding data collection methods, refer to DOI: 10.1016/j.jembe.2015.02.017.

  4. Analyzing Milestones in Smoking Cessation: Illustration in a Nicotine Patch Trial in Adult Smokers

    ERIC Educational Resources Information Center

    Shiffman, Saul; Scharf, Deborah M.; Shadel, William G.; Gwaltney, Chad J.; Dang, Qianyu; Paton, Stephanie M.; Clark, Duncan B.

    2006-01-01

    Tests of addiction treatments seldom reveal where treatment exercises its effect (i.e., promoting initial abstinence, preventing lapses, and/or impeding progression from lapse to relapse). The authors illustrate analyses distinguishing effects on these milestones in a randomized trial of high-dose nicotine patch (35 mg; n = 188) versus placebo (n…

  5. Fatigue behavior of a thermally-activated NiTiNb SMA-FRP patch

    NASA Astrophysics Data System (ADS)

    El-Tahan, M.; Dawood, M.

    2016-01-01

    This paper presents the details of an experimental study that was conducted to characterize the fatigue behavior of a thermally-activated shape memory alloy (SMA)/carbon fiber reinforced polymer (CFRP) patch that can be used to repair cracked steel members. A total of 14 thermally-activated patches were fabricated and tested to evaluate the stability of the prestress under fatigue loading. The parameters considered in this study are the prestress level in the nickel-titanium-niobium SMA wires and the applied force range. An empirical model to predict the degradation of the prestress is also presented. The results indicate that patches for which the maximum applied loads in a fatigue cycle did not cause debonding of the SMA wires from the CFRP sustained two million loading cycles with less than 20% degradation of the prestress.

  6. Reduction in Stress Intensity Factor of a Compact Tension Specimen by Bonding Symmetrical GFRP Patches

    NASA Astrophysics Data System (ADS)

    Shinde, P. S.; Tripathi, V. K.; Singh, K. K.; Sarkar, P. K.; Kumar, P.

    2013-10-01

    Reduction in stress intensity factor (SIF) of an acrylic compact tension (CT) specimen is studied by symmetrical bonding of glass fiber reinforced plastic (GFRP) patches on both sides of the specimen. The CT specimen was designed and developed to satisfy all dimensional constraints for plane strain condition. A suitable load fixture using dead weight for higher accuracy was designed for the purpose. The numerical and experimental analysis of CT specimen with varying geometry of the GFRP patches was carried out to analyze their effect on SIF of the specimen. The strain near the crack tip was measured by bonding a small strain gauge to estimate the equivalent SIF of the CT specimen. The test data was compared with the results of numerical analysis carried out using ANSYS software. The variation in strain value determined through theoretical analysis, numerical evaluation and experimental measurement is within 7 %. The equivalent SIF was found to be drastically reduced after bonding the CT specimen with GFRP patches.

  7. Development of a self-stressing NiTiNb shape memory alloy (SMA)/fiber reinforced polymer (FRP) patch

    NASA Astrophysics Data System (ADS)

    El-Tahan, M.; Dawood, M.; Song, G.

    2015-06-01

    The objective of this research is to develop a self-stressing patch using a combination of shape memory alloys (SMAs) and fiber reinforced polymer (FRP) composites. Prestressed carbon FRP patches are emerging as a promising alternative to traditional methods to repair cracked steel structures and civil infrastructure. However, prestressing these patches typically requires heavy and complex fixtures, which is impractical in many applications. This paper presents a new approach in which the prestressing force is applied by restraining the shape memory effect of NiTiNb SMA wires. The wires are subsequently embedded in an FRP overlay patch. This method overcomes the practical challenges associated with conventional prestressing. This paper presents the conceptual development of the self-stressing patch with the support of experimental observations. The bond between the SMA wires and the FRP is evaluated using pull-out tests. The paper concludes with an experimental study that evaluates the patch response during activation subsequent monotonic tensile loading. The results demonstrate that the self-stressing patch with NiTiNb SMA is capable of generating a significant prestressing force with minimal tool and labor requirements.

  8. Robust Observation Detection for Single Object Tracking: Deterministic and Probabilistic Patch-Based Approaches

    PubMed Central

    Zulkifley, Mohd Asyraf; Rawlinson, David; Moran, Bill

    2012-01-01

    In video analytics, robust observation detection is very important as the content of the videos varies a lot, especially for tracking implementation. Contrary to the image processing field, the problems of blurring, moderate deformation, low illumination surroundings, illumination change and homogenous texture are normally encountered in video analytics. Patch-Based Observation Detection (PBOD) is developed to improve detection robustness to complex scenes by fusing both feature- and template-based recognition methods. While we believe that feature-based detectors are more distinctive, however, for finding the matching between the frames are best achieved by a collection of points as in template-based detectors. Two methods of PBOD—the deterministic and probabilistic approaches—have been tested to find the best mode of detection. Both algorithms start by building comparison vectors at each detected points of interest. The vectors are matched to build candidate patches based on their respective coordination. For the deterministic method, patch matching is done in 2-level test where threshold-based position and size smoothing are applied to the patch with the highest correlation value. For the second approach, patch matching is done probabilistically by modelling the histograms of the patches by Poisson distributions for both RGB and HSV colour models. Then, maximum likelihood is applied for position smoothing while a Bayesian approach is applied for size smoothing. The result showed that probabilistic PBOD outperforms the deterministic approach with average distance error of 10.03% compared with 21.03%. This algorithm is best implemented as a complement to other simpler detection methods due to heavy processing requirement. PMID:23202226

  9. Interpatch movement of the red milkweed beetle, Tetraopes tetraophthalmus: individual responses to patch size and isolation.

    PubMed

    Matter, Stephen F

    1996-03-01

    Individual movement patterns and the effects of host plant patch size and isolation on patch occupancy were examined for red milkweed beetles, Tetraopes tetraophthalmus, residing in a heterogeneous landscape. Male beetles were found to move both more often and farther between host plant patches than female beetles, and this difference affected the patterns of patch occupancy observed. Overall, unoccupied milkweed patches were smaller and more isolated than patches occupied by beetles. Patches uninhabited by females tended to be more isolated, but not necessarily smaller, than patches with female beetles, indicating that females may be affected more by patch isolation than patch size. Presence of male beetles on patches showed a stronger response to patch size than to patch isolation. Differences in movement between males and females illustrate the need for demographically based dispersal data. Comparisons of Tetraopes interpatch movement patterns between landscapes composed of patches of different size revealed that landscapes with overall smaller patches may have greater rates of interpatch movement.

  10. Patch size and landscape effects on density and nesting success of grassland birds

    USGS Publications Warehouse

    Winter, M.; Johnson, D.H.; Shaffer, J.A.; Donovan, T.M.; Svedarsky, W.D.

    2006-01-01

    Current management recommendations for grassland birds in North America emphasize providing large patches of grassland habitat within landscapes that have few forest or shrubland areas. These Bird Conservation Areas are being proposed under the assumption that large patches of habitat in treeless landscapes will maintain viable populations of grassland birds. This assumption requires that patch size and landscape features affect density and nesting success of grassland birds, and that these effects are consistent among years and regions and across focal species. However, these assumptions have not yet been validated for grassland birds, and the relative importance of local vegetation structure, patch size, and landscape composition on grassland bird populations Is not well known. In addition, factors influencing grassland bird nesting success have been investigated mostly in small-scale and short-duration studies. To develop management guidelines for grassland birds, we tested the spatial and temporal repeatability of the influence of patch size and landscape composition on density and nesting success of 3 grassland passerines, after controlling for local-scale vegetation structure, climate, and-when analyzing nest success-bird density. We conducted our study during 4 years (1998-2001) in 44 study plots that were set up in 3 regions of the northern tallgrass prairie in Minnesota and North Dakota, USA. In these study plots we measured density and nesting success of clay-colored sparrows (Spizella pallida), Savannah sparrows (Passerculus sandwichensis), and bobolinks (Dolichonyx oryzivorusj. Statistical models indicated that density was influenced by patch size, landscape, region, and local vegetation structure more so than by local vegetation structure alone. Both magnitude and direction of the response of density to patch size varied among regions, years, and species. In contrast, the direction of landscape effects was consistent among regions, years, and between

  11. Sexual segregation of forage patch use: Support for the social-factors and predation hypotheses.

    PubMed

    Biggerstaff, Michael T; Lashley, Marcus A; Chitwood, M Colter; Moorman, Christopher E; DePerno, Christopher S

    2017-03-01

    Nearly all species of sexually dimorphic ungulates sexually segregate. Several hypotheses have been proposed to explain this phenomenon, including the social-factors hypothesis (SFH) and the predation hypothesis (PH). Interestingly, previous studies have accepted and rejected each hypothesis within and across species but few studies have simultaneously tested both hypotheses in the same population. In August 2011 and 2012 using 7680 photographs taken with camera traps in standardized forage patches, we tested two predictions of the SFH: 1) foraging efficiency of both sexes would decrease when foraging rate in mixed-sex groups relative to single-sex groups, and 2) activity patterns (i.e., the pattern of temporal use of forage patches on a diel scale) of the sexes would decrease in temporal overlap at the forage patch level (i.e., social segregation) compared to the overall temporal overlap of activity patterns of the population. Also, we tested two predictions of the +PH : 1) the relationship between feeding rates of each sex, and 2) temporal activity overlap would change with changing risk level of forage patches as a result of differing risk perception between sexes. In support of the SFH for temporal segregation, when in mixed-sex groups, mature males and all females decreased feeding rate 30% and 10%, respectively; further, the sexes had similar activity patterns overall (94-95% overlap), though temporal overlap was lower in individual forage patches (68-74% overlap). In multi-male mixed sex groups, at least one male exhibited aggressive posture toward females during all foraging bouts suggesting intersex aggression was the cause of the observed decrease in foraging rates. In support of the PH , the sexes adjusted feeding rate differently in response to changing risk level of a forage patch, encouraging spatial segregation; however, the PH was not supported for temporal segregation because temporal activity pattern overlap did not vary as a function of predation

  12. Patch forest: a hybrid framework of random forest and patch-based segmentation

    NASA Astrophysics Data System (ADS)

    Xie, Zhongliu; Gillies, Duncan

    2016-03-01

    The development of an accurate, robust and fast segmentation algorithm has long been a research focus in medical computer vision. State-of-the-art practices often involve non-rigidly registering a target image with a set of training atlases for label propagation over the target space to perform segmentation, a.k.a. multi-atlas label propagation (MALP). In recent years, the patch-based segmentation (PBS) framework has gained wide attention due to its advantage of relaxing the strict voxel-to-voxel correspondence to a series of pair-wise patch comparisons for contextual pattern matching. Despite a high accuracy reported in many scenarios, computational efficiency has consistently been a major obstacle for both approaches. Inspired by recent work on random forest, in this paper we propose a patch forest approach, which by equipping the conventional PBS with a fast patch search engine, is able to boost segmentation speed significantly while retaining an equal level of accuracy. In addition, a fast forest training mechanism is also proposed, with the use of a dynamic grid framework to efficiently approximate data compactness computation and a 3D integral image technique for fast box feature retrieval.

  13. Laser-assisted patch clamping: a methodology

    NASA Technical Reports Server (NTRS)

    Henriksen, G. H.; Assmann, S. M.; Evans, M. L. (Principal Investigator)

    1997-01-01

    Laser microsurgery can be used to perform both cell biological manipulations, such as targeted cell ablation, and molecular genetic manipulations, such as genetic transformation and chromosome dissection. In this report, we describe a laser microsurgical method that can be used either to ablate single cells or to ablate a small area (1-3 microns diameter) of the extracellular matrix. In plants and microorganisms, the extracellular matrix consists of the cell wall. While conventional patch clamping of these cells, as well as of many animal cells, requires enzymatic digestion of the extracellular matrix, we illustrate that laser microsurgery of a portion of the wall enables patch clamp access to the plasma membrane of higher plant cells remaining situated in their tissue environment. What follows is a detailed description of the construction and use of an economical laser microsurgery system, including procedures for single cell and targeted cell wall ablation. This methodology will be of interest to scientists wishing to perform cellular or subcellular ablation with a high degree of accuracy, or wishing to study how the extracellular matrix affects ion channel function.

  14. Geometry of the infalling causal patch

    NASA Astrophysics Data System (ADS)

    Freivogel, Ben; Jefferson, Robert A.; Kabir, Laurens; Yang, I.-Sheng

    2015-02-01

    The firewall paradox states that an observer falling into an old black hole must see a violation of unitarity, locality, or the equivalence principle. Motivated by this remarkable conflict, we analyze the causal structure of black hole spacetimes in order to determine whether all the necessary ingredients for the paradox fit within a single observer's causal patch. We particularly focus on the question of whether the interior partner modes of the outgoing Hawking quanta can, in principle, be measured by an infalling observer. Since the relevant modes are spread over the entire sphere, we answer a simple geometrical question: can any observer see an entire sphere behind the horizon? We find that for all static black holes in 3 +1 and higher dimensions, with any value of the cosmological constant, no single observer can see both the early Hawking radiation and the interior modes with low angular momentum. We present a detailed description of the causal patch geometry of the Schwarzschild black hole in 3 +1 dimensions, where an infalling observer comes closest to being able to measure the relevant modes.

  15. Ultra low concentration deltamethrin loaded patch development and evaluation of its repellency against dengue vector Aedes (S) albopictus

    PubMed Central

    2013-01-01

    Background Mosquito repellents and emanators confer protection against mosquito bites through spatial action of emanated vapours which are released into the adjoining environment. Synthetic insecticides released into the environment in ultra low volume vapour phase deter the mosquitoes from biting humans in a protected space. Methods Formulation patches were prepared using the solvent evaporation method over a backing membrane and using Dibutylphthalate (DBT) as a plasticizer. The effect of formulation variables on the deltamethrin release from the patch matrices were studied under accelerated conditions, whereas, HPLC was used for quantitative estimation of deltamethrin. The prepared patch formulations were subjected to physicochemical studies, such as, deltamethrin content, thickness, weight variation, percent moisture content, moisture uptake, surface area and surface pH determination. Deltamethrin-polymer interaction and compatibility was ascertained using DSC and FT-IR, while surface morphology and deltamethrin distribution in the patch were studied using SEM technique. Repellent activity of the patch formulations was evaluated against Ae. albopictus mosquitoes. Results Blends of polymeric combinations of polyvinylpyrrolidone (PVP) and ethyl-cellulose (EC) with admixture of deltamethrin provided prolonged repellent activity against Ae. albopictus mosquitoes. Physicochemical characterisation indicated the suitability of deltamethrin patch formulation with the polymeric combinations of PVP and EC. Patches were very effective against laboratory reared Ae. albopictus mosquitoes. No significant difference was observed between the performance of test patches and commercially available repellent cream Mosqshield®. Conclusion Deltamethrin loaded patches provided effective repellency against Ae. albopictus mosquitoes. The study emphasised that deltamethrin released to the environment in low concentration could be an excellent spatial repellent against hematophagous

  16. Patch size has no effect on insect visitation rate per unit area in garden-scale flower patches

    NASA Astrophysics Data System (ADS)

    Garbuzov, Mihail; Madsen, Andy; Ratnieks, Francis L. W.

    2015-01-01

    Previous studies investigating the effect of flower patch size on insect flower visitation rate have compared relatively large patches (10-1000s m2) and have generally found a negative relationship per unit area or per flower. Here, we investigate the effects of patch size on insect visitation in patches of smaller area (range c. 0.1-3.1 m2), which are of particular relevance to ornamental flower beds in parks and gardens. We studied two common garden plant species in full bloom with 6 patch sizes each: borage (Borago officinalis) and lavender (Lavandula × intermedia 'Grosso'). We quantified flower visitation by insects by making repeated counts of the insects foraging at each patch. On borage, all insects were honey bees (Apis mellifera, n = 5506 counts). On lavender, insects (n = 737 counts) were bumble bees (Bombus spp., 76.9%), flies (Diptera, 22.4%), and butterflies (Lepidoptera, 0.7%). On both plant species we found positive linear effects of patch size on insect numbers. However, there was no effect of patch size on the number of insects per unit area or per flower and, on lavender, for all insects combined or only bumble bees. The results show that it is possible to make unbiased comparisons of the attractiveness of plant species or varieties to flower-visiting insects using patches of different size within the small scale range studied and make possible projects aimed at comparing ornamental plant varieties using existing garden flower patches of variable area.

  17. Influence of habitat quality, population size, patch size, and connectivity on patch-occupancy dynamics of the middle spotted woodpecker.

    PubMed

    Robles, Hugo; Ciudad, Carlos

    2012-04-01

    Despite extensive research on the effects of habitat fragmentation, the ecological mechanisms underlying colonization and extinction processes are poorly known, but knowledge of these mechanisms is essential to understanding the distribution and persistence of populations in fragmented habitats. We examined these mechanisms through multiseason occupancy models that elucidated patch-occupancy dynamics of Middle Spotted Woodpeckers (Dendrocopos medius) in northwestern Spain. The number of occupied patches was relatively stable from 2000 to 2010 (15-24% of 101 patches occupied every year) because extinction was balanced by recolonization. Larger and higher quality patches (i.e., higher density of oaks >37 cm dbh [diameter at breast height]) were more likely to be occupied. Habitat quality (i.e., density of large oaks) explained more variation in patch colonization and extinction than did patch size and connectivity, which were both weakly associated with probabilities of turnover. Patches of higher quality were more likely to be colonized than patches of lower quality. Populations in high-quality patches were less likely to become extinct. In addition, extinction in a patch was strongly associated with local population size but not with patch size, which means the latter may not be a good surrogate of population size in assessments of extinction probability. Our results suggest that habitat quality may be a primary driver of patch-occupancy dynamics and may increase the accuracy of models of population survival. We encourage comparisons of competing models that assess occupancy, colonization, and extinction probabilities in a single analytical framework (e.g., dynamic occupancy models) so as to shed light on the association of habitat quality and patch geometry with colonization and extinction processes in different settings and species.

  18. Low dielectric polyimide aerogels as substrates for lightweight patch antennas.

    PubMed

    Meador, Mary Ann B; Wright, Sarah; Sandberg, Anna; Nguyen, Baochau N; Van Keuls, Frederick W; Mueller, Carl H; Rodríguez-Solís, Rafael; Miranda, Félix A

    2012-11-01

    The dielectric properties and loss tangents of low-density polyimide aerogels have been characterized at various frequencies. Relative dielectric constants as low as 1.16 were measured for polyimide aerogels made from 2,2'-dimethylbenzidine (DMBZ) and biphenyl 3,3',4,4'-tetracarbozylic dianhydride (BPDA) cross-linked with 1,3,5-triaminophenoxybenzene (TAB). This formulation was used as the substrate to fabricate and test prototype microstrip patch antennas and benchmark against state of practice commercial antenna substrates. The polyimide aerogel antennas exhibited broader bandwidth, higher gain, and lower mass than the antennas made using commercial substrates. These are very encouraging results, which support the potential advantages of the polyimide aerogel-based antennas for aerospace applications.

  19. Active AU Based Patch Weighting for Facial Expression Recognition

    PubMed Central

    Xie, Weicheng; Shen, Linlin; Yang, Meng; Lai, Zhihui

    2017-01-01

    Facial expression has many applications in human-computer interaction. Although feature extraction and selection have been well studied, the specificity of each expression variation is not fully explored in state-of-the-art works. In this work, the problem of multiclass expression recognition is converted into triplet-wise expression recognition. For each expression triplet, a new feature optimization model based on action unit (AU) weighting and patch weight optimization is proposed to represent the specificity of the expression triplet. The sparse representation-based approach is then proposed to detect the active AUs of the testing sample for better generalization. The algorithm achieved competitive accuracies of 89.67% and 94.09% for the Jaffe and Cohn–Kanade (CK+) databases, respectively. Better cross-database performance has also been observed. PMID:28146094

  20. Studying mechanosensitive ion channels with an automated patch clamp.

    PubMed

    Barthmes, Maria; Jose, Mac Donald F; Birkner, Jan Peter; Brüggemann, Andrea; Wahl-Schott, Christian; Koçer, Armağan

    2014-03-01

    Patch clamp electrophysiology is the main technique to study mechanosensitive ion channels (MSCs), however, conventional patch clamping is laborious and success and output depends on the skills of the operator. Even though automated patch systems solve these problems for other ion channels, they could not be applied to MSCs. Here, we report on activation and single channel analysis of a bacterial mechanosensitive ion channel using an automated patch clamp system. With the automated system, we could patch not only giant unilamellar liposomes but also giant Escherichia coli (E. coli) spheroplasts. The tension sensitivity and channel kinetics data obtained in the automated system were in good agreement with that obtained from the conventional patch clamp. The findings will pave the way to high throughput fundamental and drug screening studies on mechanosensitive ion channels.

  1. Single Image Super-resolution using Deformable Patches

    PubMed Central

    Zhu, Yu; Zhang, Yanning; Yuille, Alan L.

    2014-01-01

    We proposed a deformable patches based method for single image super-resolution. By the concept of deformation, a patch is not regarded as a fixed vector but a flexible deformation flow. Via deformable patches, the dictionary can cover more patterns that do not appear, thus becoming more expressive. We present the energy function with slow, smooth and flexible prior for deformation model. During example-based super-resolution, we develop the deformation similarity based on the minimized energy function for basic patch matching. For robustness, we utilize multiple deformed patches combination for the final reconstruction. Experiments evaluate the deformation effectiveness and super-resolution performance, showing that the deformable patches help improve the representation accuracy and perform better than the state-of-art methods. PMID:25473254

  2. Effect of Eye Patching in Rehabilitation of Hemispatial Neglect

    PubMed Central

    Smania, Nicola; Fonte, Cristina; Picelli, Alessandro; Gandolfi, Marialuisa; Varalta, Valentina

    2013-01-01

    Eye patching (EP; monocular or right hemifield) has been proposed to improve visuospatial attention to the ignored field in patients with hemispatial neglect. The aim of this paper is to review the literature on the effects of EP in hemispatial neglect after stroke in order to convey evidence-based recommendations to clinicians in stroke rehabilitation. Thirteen intervention studies were selected from the Medline, EMBASE, Scopus, Cochrane Library, CINAHL, PsychINFO, EBRSR, and Health Star databases. Methodological quality was defined according to the Physiotherapy Evidence Database. Overall, seven studies used monocular EP, five used right hemifield patching, and one compared right monocular with right hemifield patching. Seven studies compared normal viewing to monocular or hemifield patching conditions. Six studies included a period of treatment. As to the monocular EP, four studies reported positive effects of right monocular patching. One study showed an improvement in hemispatial neglect with left monocular patching. Two studies found no superiority of right vs. left monocular patching. One study found no effects of right monocular patching. As to the right hemifield EP, one study showed improvements in neglect after right hemifield patching. Three studies found that right hemifield patching combined with another rehabilitation technique was more effective than that treatment alone. One study found no differences between right hemifield patching combined with another treatment and that treatment alone. One study found the same effect between right hemifield patching alone and another rehabilitation technique. Our results globally tend to support the usefulness of right hemifield EP in clinical practice. In order to define a level of evidence with the standard rehabilitation evidence rating tools, further properly powered randomized controlled trials or meta-analysis are needed. PMID:24032011

  3. The Hedgehog Receptor Patched Is Involved in Cholesterol Transport

    PubMed Central

    Bidet, Michel; Joubert, Olivier; Lacombe, Benoit; Ciantar, Marine; Nehmé, Rony; Mollat, Patrick; Brétillon, Lionel; Faure, Hélène; Bittman, Robert; Ruat, Martial; Mus-Veteau, Isabelle

    2011-01-01

    Background Sonic hedgehog (Shh) signaling plays a crucial role in growth and patterning during embryonic development, and also in stem cell maintenance and tissue regeneration in adults. Aberrant Shh pathway activation is involved in the development of many tumors, and one of the most affected Shh signaling steps found in these tumors is the regulation of the signaling receptor Smoothened by the Shh receptor Patched. In the present work, we investigated Patched activity and the mechanism by which Patched inhibits Smoothened. Methodology/Principal Findings Using the well-known Shh-responding cell line of mouse fibroblasts NIH 3T3, we first observed that enhancement of the intracellular cholesterol concentration induces Smoothened enrichment in the plasma membrane, which is a crucial step for the signaling activation. We found that binding of Shh protein to its receptor Patched, which involves Patched internalization, increases the intracellular concentration of cholesterol and decreases the efflux of a fluorescent cholesterol derivative (BODIPY-cholesterol) from these cells. Treatment of fibroblasts with cyclopamine, an antagonist of Shh signaling, inhibits Patched expression and reduces BODIPY-cholesterol efflux, while treatment with the Shh pathway agonist SAG enhances Patched protein expression and BODIPY-cholesterol efflux. We also show that over-expression of human Patched in the yeast S. cerevisiae results in a significant boost of BODIPY-cholesterol efflux. Furthermore, we demonstrate that purified Patched binds to cholesterol, and that the interaction of Shh with Patched inhibits the binding of Patched to cholesterol. Conclusion/Significance Our results suggest that Patched may contribute to cholesterol efflux from cells, and to modulation of the intracellular cholesterol concentration. This activity is likely responsible for the inhibition of the enrichment of Smoothened in the plasma membrane, which is an important step in Shh pathway activation. PMID

  4. An Optimal Cell Detection Technique for Automated Patch Clamping

    NASA Technical Reports Server (NTRS)

    McDowell, Mark; Gray, Elizabeth

    2004-01-01

    While there are several hardware techniques for the automated patch clamping of cells that describe the equipment apparatus used for patch clamping, very few explain the science behind the actual technique of locating the ideal cell for a patch clamping procedure. We present a machine vision approach to patch clamping cell selection by developing an intelligent algorithm technique that gives the user the ability to determine the good cell to patch clamp in an image within one second. This technique will aid the user in determining the best candidates for patch clamping and will ultimately save time, increase efficiency and reduce cost. The ultimate goal is to combine intelligent processing with instrumentation and controls in order to produce a complete turnkey automated patch clamping system capable of accurately and reliably patch clamping cells with a minimum amount of human intervention. We present a unique technique that identifies good patch clamping cell candidates based on feature metrics of a cell's (x, y) position, major axis length, minor axis length, area, elongation, roundness, smoothness, angle of orientation, thinness and whether or not the cell is only particularly in the field of view. A patent is pending for this research.

  5. Facile route to morphologically tailored silver patches on colloidal particles.

    PubMed

    Klupp Taylor, Robin N; Bao, Huixin; Tian, Chenting; Vasylyev, Serhiy; Peukert, Wolfgang

    2010-08-17

    Here we demonstrate, for the first time, the heterogeneous nucleation and growth of silver patches on submicrometer silica spheres. While patches can be grown directly onto native silica particles, it is shown that a higher patch yield can be obtained by first treating the silica with a mixture of an alkanolamine and silver nitrate. Variation of the pretreatment and subsequent coating reactions allowed the patch yield, number, size, thickness, and shape to be adjusted. The patchy particles were shown to possess plasmon modes extending from the visible into the near-IR region, making these structures highly interesting for both their asymmetric morphological and functional properties.

  6. Acute Reversible Charles Bonnet Syndrome Following Eye Patch Placement.

    PubMed

    Nan, Lian; Yanbin, Hou; Jingping, Zhao

    2013-01-01

    Charles Bonnet syndrome (CBS) is characterised by recurrent vivid visual hallucinations in the presence of normal cognition. We present a case of CBS secondary to eye patching following Pars Plana Vitrectomy with an unusually acute onset in a 48-year-old woman. She presented with formed visual hallucinations that started less than 30 min after patching of her left eye. The patch was removed after 2 d, and these hallucinations persisted 2 d following eye patch removal. It is important that the ophthalmic surgeon be aware of the potential for development of CBS and offer appropriate referral and reassurance should it occur.

  7. In Vitro System for Measuring Chordal Force Changes Following Mitral Valve Patch Repair

    PubMed Central

    Ostli, B; Vester-Petersen, J; Askov, JB; Honge, JL; Levine, RA; Hagège, A; Nielsen, SL; Hasenkam, JM; Nygaard, H; Jensen, MO

    2013-01-01

    Background Attention towards optimization of mitral valve repair methods is increasing. Patch augmentation is one strategy utilized to correct functional mitral regurgitation or systolic anterior motion in complex mitral valve repairs. This article describes a system for investigating the redistribution of chordae tendineae tension as a reflection of altered stress distribution of the valve leaflet following patch augmentation. Methods and materials An in vitro test setup was constructed to hold native porcine mitral valves containing an annulus and papillary muscle positioning system. The alterations caused by patch augmentation should be visual from both the atrial and ventricular views. Ventricular pressure was regulated stepwise in a range of 0-150 mmHg. To test the system, the anterior mitral leaflet was extended by a pericardial patch sutured to the mid/basal part of the leaflet, and the chordae tendineae force was measured as the ventricular pressure was applied. Results The system demonstrated the capacity to hold native porcine mitral valves and introducing patch repairs according to clinical practice. The porcine mitral valve test setup indicated strong correlation between the forces in the mitral valve secondary chordae tendineae and the applied transvalvular pressure (R2 = 0.95). Conclusion This test setup proved the ability to obtain normal mid-systolic mitral valve function, secondary chordae force measurements, and important preservation of the visual access: Hence, obtaining the pressure-force relationship as well as identifying any shift of the secondary chordae insertion point on the anterior leaflet relative to the coaptation zone was made possible. PMID:26273417

  8. Two Holes in 'Wooly Patch' (False Color)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The rock abrasion tool on NASA's Mars Exploration Rover Spirit ground two holes in a relatively soft rock called 'Wooly Patch' near the base of the 'Columbia Hills' inside Gusev Crater on Mars. This false-color image from the panoramic camera was taken on sol 200 (July 25, 2004) and generated using the camera's 750-, 530-, and 430-nanometer filters. It highlights the material ground up by the rock abrasion tool, grayish-blue in appearance in this image. The color of the material excavated suggests the interior of the rock contains iron minerals that are less oxidized than the dust or possibly weathered coating on the exterior of the rock. Scientists speculate that this relatively soft rock (compared to others analyzed by Spirit) may have been modified by water. Small cracks in the surface outside the drill holes may be the result of interactions with water-rich fluids.

  9. Behavioral response races, predator-prey shell games, ecology of fear, and patch use of pumas and their ungulate prey.

    PubMed

    Laundré, John W

    2010-10-01

    The predator-prey shell game predicts random movement of prey across the landscape, whereas the behavioral response race and landscape of fear models predict that there should be a negative relationship between the spatial distribution of a predator and its behaviorally active prey. Additionally, prey have imperfect information on the whereabouts of their predator, which the predator should incorporate in its patch use strategy. I used a one-predator-one-prey system, puma (Puma concolor)-mule deer (Odocoileus hemionus) to test the following predictions regarding predator-prey distribution and patch use by the predator. (1) Pumas will spend more time in high prey risk/low prey use habitat types, while deer will spend their time in low-risk habitats. Pumas should (2) select large forage patches more often, (3) remain in large patches longer, and (4) revisit individual large patches more often than individual smaller ones. I tested these predictions with an extensive telemetry data set collected over 16 years in a study area of patchy forested habitat. When active, pumas spent significantly less time in open areas of low intrinsic predation risk than did deer. Pumas used large patches more than expected, revisited individual large patches significantly more often than smaller ones, and stayed significantly longer in larger patches than in smaller ones. The results supported the prediction of a negative relationship in the spatial distribution of a predator and its prey and indicated that the predator is incorporating the prey's imperfect information about its presence. These results indicate a behavioral complexity on the landscape scale that can have far-reaching impacts on predator-prey interactions.

  10. Measured Leak Rate of Ammonia Through an Epoxy/Stainless-Steel Patch

    DTIC Science & Technology

    2007-08-10

    temperature to accelerate degradation phenomena. No gross failures of the patches were observed in four weeks of testing. No significant difference... alu - minum 6063 T4 condenser lines. This pitting corrosion could eventually cause small holes to form in the condenser line. This end result was...testing and evaluation. Space Materials Laboratory: Evaluation and characterizations of new materials and processing techniques: metals, alloys , ceramics

  11. Smart patches: self-monitoring composite patches for the repair of aircraft

    NASA Astrophysics Data System (ADS)

    Crossley, Samuel D.; Marioli-Riga, Zaira; Tsamasphyros, George; Kanderakis, George; Furnarakis, Nikos; Ikiades, Aris; Konstantaki, Mary

    2004-03-01

    Conventional aircraft repair techniques employ bolted or riveted metallic reinforcements, which frequently introduce additional stress concentrations leading to further cracking and creating areas difficult or impossible to inspect. Bonded composite repairs ("patches") result in the elimination of stress concentrations caused by additional fastener holes, improved strength to weight ratio and present a sealed interface. This reduces even further the danger of corrosion and fretting under the repair, gives greater flexibility in design and lessens application time while lengthening fatigue life. Embedding optical fibres and sensors into the patch, and combining this with advanced data collection and processing systems, creating a so-called "smart patch", will enable the real-time assessment of aircraft structural integrity resulting in reliable prediction of maintenance requirements for repaired structures. This paper describes the current state of the art in smart patch technology, and includes a detailed description of the measurement problem and of the work being undertaken to solve it, at both the component and system level. An analysis of typical crack behaviour, based on FE modelling is presented and this demonstrates the need for optical strain sensors having a very short gauge length. The paper discusses the advantages and limitations of very short Fibre Bragg Gratings (FBGs) in this context and also provides early experimental data from 1mm and 2mm gratings which have been fabricated for this purpose. The paper also describes the impact of the measurement and environmental constraints on the design of the FBG interrogation system and presents the results of initial trials. The work is being undertaken in the framework of a collaborative project (ACIDS) which is co-funded by the European Commission.

  12. Pharmacokinetics of lidocaine delivered from a transmucosal patch in children.

    PubMed Central

    Leopold, Andrea; Wilson, Stephen; Weaver, Joel S.; Moursi, Amr M.

    2002-01-01

    The DentiPatch lidocaine transoral delivery system (Noven Pharmaceuticals) is indicated for mild topical anesthesia of mucosal membranes in the mouth. The DentiPatch is a mucoadhesive patch containing 46.1 mg of lidocaine (20% concentration). Current studies in adults report that DentiPatch application produces very low plasma concentrations of lidocaine. However, it is not known what plasma levels are obtained when the same dosage is used in children. The purpose of this study was to determine whether the plasma lidocaine concentrations generated by the DentiPatch are within a safe range for children. The sample in this study was 11 children aged 2-7 years requiring general anesthesia for comprehensive dental care. A lidocaine DentiPatch was placed on the buccal mucosa above the maxillary incisors for 5 minutes. Blood samples were drawn before placing the DentiPatch and at various time intervals after removing it. Blood samples were analyzed by fluorescence polarization immunoassay to determine the plasma concentrations of lidocaine and its major metabolite, monoethylglycinexylidide. The lidocaine and monoethylglycinexylidide absorbed from the DentiPatch did not reach toxic plasma levels in children. However, plasma concentrations were much higher than in adults and were high enough to require inclusion in the calculation of total lidocaine administered to a pediatric patient. Images Figure 1 PMID:15384296

  13. FDTD Analysis of U-Slot Rectangular Patch Antenna

    NASA Technical Reports Server (NTRS)

    Luk, K. M.; Tong, K. F.; Shum, S. M.; Lee, K. F.; Lee, R. Q.

    1997-01-01

    The U-slot rectangular patch antenna (Figure I) has been found experimentally to provide impedance and gain bandwidths of about 300 without the need of stacked or coplanar parasitic elements [1,2]. In this paper, simulation results of the U-slot patch using FDTD analysis are presented. Comparison with measured results are given.

  14. Intrinsic modes of radiation in ferrite patch antennas

    NASA Astrophysics Data System (ADS)

    How, Hoton; Fang, Ta-Ming; Vittoria, Carmine

    1994-06-01

    We have found two types of radiation modes for patch antennas loaded with ferrite materials. Each mode of radiation is a linear combination of normal modes of propagation in parallel plate waveguide separated by a slab of ferrite material. We have introduced new boundary conditions in which only TE modes of oscillation in the patch antenna cavity result.

  15. Rabies vaccination in dogs using a dissolving microneedle patch.

    PubMed

    Arya, Jaya M; Dewitt, Kristopher; Scott-Garrard, Maya; Chiang, Yu-Wei; Prausnitz, Mark R

    2016-10-10

    Because humans get rabies primarily through dog bites, stray dog population control and mass or mandatory vaccination of domestic dogs and other animals has virtually eliminated human rabies in industrialized countries. However, thousands of people in developing countries die of rabies each year due to the inability to control dog populations and implement mass vaccination because of financial, logistical and other challenges. The availability of an easier-to-administer and more cost-effective vaccine may help to address some of these issues. Here, we propose the use of dissolving microneedle patches for simple and potentially cost-effective rabies vaccination, and assess the safety and immunogenicity of microneedle patch vaccination using a rabies DNA vaccine in dogs. The vaccine was stable upon formulation and storage for at least 3weeks at 4°C in a microneedle patch. For vaccination, the patches were applied to the inner ear by hand without an applicator. Microneedle patches were well tolerated in the skin, with mild erythema, minimal wheal formation and complete resolution of skin reactions within 7days, and generated no systemic adverse events. Microneedle patches were at least as immunogenic as intramuscular injection at the same dose, as demonstrated by similar serum neutralizing antibody titers. A ten-fold lower vaccine dose administered by microneedle patch generated a weaker immune response compared to full-dose intramuscular vaccination. We conclude that dissolving microneedle patches may provide an innovative approach to mass vaccination of dogs.

  16. 270. OFFICERS' QUARTERS (FORMER SUMMER COTTAGES) AT DOG PATCH BEACH, ...

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

    270. OFFICERS' QUARTERS (FORMER SUMMER COTTAGES) AT DOG PATCH BEACH, C. 1939. VIEW NORTH DOWN GREENWICH ROAD TOWARD FORMER SUMMER COTTAGES, CONVERTED TO OFFICER'S QUARTERS, OVER-LOOKING DOG PATCH BEACH. - Quonset Point Naval Air Station, Roger Williams Way, North Kingstown, Washington County, RI

  17. Reduction of Rhizoctonia bare patch win wheat with barley rotations.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizoctonia bare patch caused by Rhizoctonia solani AG-8 is a major fungal root disease in no-till cropping systems. In an 8-year experiment comparing various dryland no-till cropping systems near Ritzville, Washington, Rhizoctonia bare patch first appeared in year 3 and continued through year 8. ...

  18. Cell-Detection Technique for Automated Patch Clamping

    NASA Technical Reports Server (NTRS)

    McDowell, Mark; Gray, Elizabeth

    2008-01-01

    A unique and customizable machinevision and image-data-processing technique has been developed for use in automated identification of cells that are optimal for patch clamping. [Patch clamping (in which patch electrodes are pressed against cell membranes) is an electrophysiological technique widely applied for the study of ion channels, and of membrane proteins that regulate the flow of ions across the membranes. Patch clamping is used in many biological research fields such as neurobiology, pharmacology, and molecular biology.] While there exist several hardware techniques for automated patch clamping of cells, very few of those techniques incorporate machine vision for locating cells that are ideal subjects for patch clamping. In contrast, the present technique is embodied in a machine-vision algorithm that, in practical application, enables the user to identify good and bad cells for patch clamping in an image captured by a charge-coupled-device (CCD) camera attached to a microscope, within a processing time of one second. Hence, the present technique can save time, thereby increasing efficiency and reducing cost. The present technique involves the utilization of cell-feature metrics to accurately make decisions on the degree to which individual cells are "good" or "bad" candidates for patch clamping. These metrics include position coordinates (x,y) in the image plane, major-axis length, minor-axis length, area, elongation, roundness, smoothness, angle of orientation, and degree of inclusion in the field of view. The present technique does not require any special hardware beyond commercially available, off-the-shelf patch-clamping hardware: A standard patchclamping microscope system with an attached CCD camera, a personal computer with an imagedata- processing board, and some experience in utilizing imagedata- processing software are all that are needed. A cell image is first captured by the microscope CCD camera and image-data-processing board, then the image

  19. Recent and relict topography of Boo Bee patch reef, Belize

    USGS Publications Warehouse

    Halley, R.B.; Shinn, E.A.; Hudson, J.H.; Lidz, B.; Taylor, D.L.

    1977-01-01

    Five core borings were taken on and around Boo Bee Patch Reef to better understand the origin of such shelf lagoon reefs. The cores reveal 4 stages of development: (1) subaerial exposure of a Pleistocene "high" having about 8 meters of relief, possibly a Pleistocene patch reef; (2) deposition of peat and impermeable terrigenous clay 3 meters thick around the high; (3) initiation of carbonate sediment production by corals and algae on the remaining 5 meters of hard Pleistocene topography and carbonate mud on the surrounding terrigenous clay; and (4) accelerated organic accumulation on the patch reef. Estimates of patch reef sedimentation rates (1.6 m/1000 years) are 3 to 4 times greater than off-reef sedimentation rates (0.4-0.5 m/1000 years). During periods of Pleistocene sedimentation on the Belize shelf, lagoon patch reefs may have grown above one another, stacking up to form reef accumulation of considerable thickness.

  20. Chronic adhesive arachnoiditis after repeat epidural blood patch.

    PubMed

    Carlswärd, C; Darvish, B; Tunelli, J; Irestedt, L

    2015-08-01

    Epidural blood patching is an effective treatment for postdural puncture headache but has potential risks. Arachnoiditis is a very rare disabling condition and few cases have been described following an epidural blood patch. We present a case of chronic adhesive arachnoiditis in a parturient treated with a repeat epidural blood patch. A healthy 29-year-old woman had an accidental dural puncture following epidural insertion during labour. Initial treatment of postdural puncture headache with an epidural blood patch was ineffective and was therefore repeated. She gradually developed severe neurological symptoms consistent with arachnoiditis confirmed with magnetic resonance imaging. Despite intensive multimodal treatment with analgesics and physiotherapy, her neurological condition remains unresolved two years later. This serious but rare complication should encourage caution when treating parturients with postdural puncture headache with a repeat epidural blood patch.

  1. Suspended Patch Antenna Array With Electromagnetically Coupled Inverted Microstrip Feed

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.

    2000-01-01

    The paper demonstrates a four-element suspended patch antenna array, with a parasitic patch layer and an electromagnetically coupled inverted microstrip feed, for linear polarization at K-Band frequencies. This antenna has the following advantages over conventional microstrip antennas: First, the inverted microstrip has lower attenuation than conventional microstrip; hence, conductor loss associated with the antenna corporate feed is lower resulting in higher gain and efficiency. Second, conventional proximity coupled patch antennas require a substrate for the feed and a superstrate for the patch. However, the inverted microstrip fed patch antenna makes use of a single substrate, and hence, is lightweight and low cost. Third, electromagnetic coupling results in wider bandwidth. Details regarding the design and fabrication will be presented as well as measured results including return loss, radiation patterns and cross-polarization levels.

  2. Patch Exploitation by female Red Flour Beetles, Tribolium castaneum

    PubMed Central

    Campbell, J. F.; Runnion, C.

    2003-01-01

    The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) has had a long association with human stored food and can be a major pest in anthropogenic structures used for the processing and storage of grain-based products. Anthropogenic structures are fragmented landscapes characterized by spatially and temporally patchy resources. Here we investigate the ability of female T. castaneum to evaluate the quality of small patches of food and to adjust the number of eggs they lay per patch (i.e., clutch size) to maximize fitness gains. In multiple choice, paired choice and no choice experiments females tended to lay more eggs in larger amounts of flour. The number of eggs that they lay in a patch of flour was consistent with that predicted to optimize production of adults from that patch (i.e., the ‘Lack’ clutch size). Progeny size was only significantly impacted in the smallest patch sizes. PMID:15841236

  3. Microstrip patch antenna receiving array operating in the Ku band

    NASA Technical Reports Server (NTRS)

    Walcher, Douglas A.

    1996-01-01

    Microstrip patch antennas were first investigated from the idea that it would be highly advantageous to fabricate radiating elements (antennas) on the same dielectric substrate as RF circuitry and transmission lines. Other advantages were soon discovered to be its lightweight, low profile, conformability to shaped surfaces, and low manufacturing costs. Unfortunately, these same patches continually exhibit narrow bandwidths, wide beamwidths, and low antenna gain. This thesis will present the design and experimental results of a microstrip patch antenna receiving array operating in the Ku band. An antenna array will be designed in an attempt to improve its performance over a single patch. Most Ku band information signals are either wide band television images or narrow band data and voice channels. An attempt to improve the gain of the array by introducing parasitic patches on top of the array will also be presented in this thesis.

  4. Patch exploitation by female red flour beetles, Tribolium castaneum.

    PubMed

    Campbell, J F; Runnion, C

    2003-01-01

    The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) has had a long association with human stored food and can be a major pest in anthropogenic structures used for the processing and storage of grain-based products. Anthropogenic structures are fragmented landscapes characterized by spatially and temporally patchy resources. Here we investigate the ability of female T. castaneum to evaluate the quality of small patches of food and to adjust the number of eggs they lay per patch (i.e., clutch size) to maximize fitness gains. In multiple choice, paired choice and no choice experiments females tended to lay more eggs in larger amounts of flour. The number of eggs that they lay in a patch of flour was consistent with that predicted to optimize production of adults from that patch (i.e., the 'Lack' clutch size). Progeny size was only significantly impacted in the smallest patch sizes.

  5. Prediction of Infant MRI Appearance and Anatomical Structure Evolution using Sparse Patch-based Metamorphosis Learning Framework

    PubMed Central

    Rekik, Islem; Li, Gang; Wu, Guorong; Lin, Weili; Shen, Dinggang

    2016-01-01

    Magnetic resonance imaging (MRI) of pediatric brain provides invaluable information for early normal and abnormal brain development. Longitudinal neuroimaging has spanned various research works on examining infant brain development patterns. However, studies on predicting postnatal brain image evolution remain scarce, which is very challenging due to the dynamic tissue contrast change and even inversion in postnatal brains. In this paper, we unprecedentedly propose a dual image intensity and anatomical structure (label) prediction framework that nicely links the geodesic image metamorphosis model with sparse patch-based image representation, thereby defining spatiotemporal metamorphic patches encoding both image photometric and geometric deformation. In the training stage, we learn the 4D metamorphosis trajectories for each training subject. In the prediction stage, we define various strategies to sparsely represent each patch in the testing image using the training metamorphosis patches; as we progressively increment the richness of the patch (from appearance-based to multimodal kinetic patches). We used the proposed framework to predict 6, 9 and 12-month brain MR image intensity and structure (white and gray matter maps) from 3 months in 10 infants. Our seminal work showed promising preliminary prediction results for the spatiotemporally complex, drastically changing brain images.

  6. Effects of coastal transport on larval patches: Models and observations

    NASA Astrophysics Data System (ADS)

    Tilburg, Charles E.; Houser, Letise T.; Steppe, Cecily N.; Garvine, Richard W.; Epifanio, Charles E.

    2006-03-01

    We used a combination of field observations and numerical modeling to examine the physical mechanisms responsible for the evolution and transport of patches of blue crab larvae in the mouth of Delaware Bay. The observations consisted of larval collections and surface salinity measurements taken along a moving spatial grid whose origin was determined by a satellite-tracked drifter. Examination of field observations revealed a slender larval patch that was aligned with salinity contours. Measurement of the salting rate of the larval patch indicated that the patch moved through the offshore edge of a buoyant plume due to wind-driven upwelling circulation. A numerical model that provided realistic simulations of the flow field at the mouth of Delaware Bay and the adjoining coastal ocean was used to examine the physical mechanisms responsible for the movement and evolution of the patch. We conducted a series of simulations in which we separately examined the effects of tides, buoyancy-driven flow, and wind-driven transport. Results showed that both tides and buoyancy-driven flow tend to elongate an initially square fluid element. Although winds alone have little effect on the shape of a patch, wind-driven flow can effectively move a patch through a complex flow field in which the deformation by tides and buoyancy-driven circulation can have significant effects. This study represents the first observation and analysis of a larval patch that remains intact while moving through the edge of a buoyant plume. It provides new insight into the shape of larval patches in Delaware Bay and any region with strong buoyancy- and tidally-driven flow, suggesting that typical larval patches may not be characterized by equal across- and alongshelf dimensions but instead tend to be slender shapes that are aligned with the flow field.

  7. Identifying preferred habitats of samango monkeys (Cercopithecus (nictitans) mitis erythrarchus) through patch use.

    PubMed

    Emerson, Sara E; Brown, Joel S

    2013-11-01

    To examine habitat preferences of two groups of samango monkeys (Cercopithecus (nictitans) mitis erythrarchus) in the Soutpansberg, South Africa, we used experimental food patches in fragments of tall forest and in bordering secondary growth short forest. Additionally, to test for the impacts of group cohesion and movement on habitat use, we tested for the interaction of space and time in our analyses of foraging intensity in the experimental food patches placed throughout the home ranges of the two groups. We expected the monkeys to harvest the most from patches in tall forest habitats and the least from patches in short forest. Further, because the monkeys move through their habitats in groups, we expected to see group cohesion effects illustrated by daily spatial variation in the monkeys’ use of widespread foraging grids. In the forest height experiments, the two groups differed in their foraging responses, with 8% greater foraging overall for one group. However, forest height did not significantly impact foraging in either group, meaning that, given feeding opportunities, samango monkeys are able to utilise secondary growth forest. For one group, missed opportunity costs of staying with the group appeared through the statistical interaction of day with foraging location (the monkeys did not always spread out to take advantage of all available food patches). In several subsequent experiments in widespread grids, significant daily spatial variation in foraging occurred, pointing to spatial cohesion during group movement as likely being an important predictor of habitat use. For an individual social forager, staying with the group may be more important than habitat type in driving habitat selection.

  8. Identifying preferred habitats of samango monkeys (Cercopithecus (nictitans) mitis, erythrarchus) through patch use.

    PubMed

    Emerson, Sara E; Brown, Joel S

    2013-10-26

    To examine habitat preferences of two groups of samango monkeys (Cercopithecus (nictitans) mitis erythrarchus) in the Soutpansberg, South Africa, we used experimental food patches in fragments of tall forest and in bordering secondary growth short forest. Additionally, to test for the impacts of group cohesion and movement on habitat use, we tested for the interaction of space and time in our analyses of foraging intensity in the experimental food patches placed throughout the home ranges of the two groups. We expected the monkeys to harvest the most from patches in tall forest habitats and the least from patches in short forest. Further, because the monkeys move through their habitats in groups, we expected to see group cohesion effects illustrated by daily spatial variation in the monkeys' use of widespread foraging grids. In the forest height experiments, the two groups differed in their foraging responses, with 8% greater foraging overall for one group. However, forest height did not significantly impact foraging in either group, meaning that, given feeding opportunities, samango monkeys are able to utilize secondary growth forest. For one group, missed opportunity costs of staying with the group appeared through the statistical interaction of day with foraging location (the monkeys did not always spread out to take advantage of all available food patches). In several subsequent experiments in widespread grids, significant daily spatial variation in foraging occurred, pointing to spatial cohesion during group movement as likely being an important predictor of habitat use. For an individual social forager, staying with the group may be more important than habitat type in driving habitat selection.

  9. Circumferential phased array of shear-horizontal wave magnetostrictive patch transducers for pipe inspection.

    PubMed

    Kim, Hoe Woong; Lee, Joo Kyung; Kim, Yoon Young

    2013-02-01

    Several investigations report effective uses of magnetostrictive patch transducers to generate and measure longitudinal and torsional guided waves in a pipe. They can be used to form a phased array for the circumferential inspection of pipes. Although there are circumferential phased arrays employing piezoelectric transducers or EMAT's, no magnetostrictive patch transducer based array system has been attempted. In this investigation, we aim to develop a circumferential phased magnetostrictive patch transducer (PMPT) array that can focus shear-horizontal waves at any target point on a cylindrical surface of a pipe. For the development, a specific configuration of a PMPT array employing six magnetostrictive patch transducers is proposed. A wave simulation model is also developed to determine time delays and amplitudes of signals generated by the transducers of the array. This model should be able to predict accurately the angular profiles of shear-horizontal waves generated by the transducers. For wave focusing, the time reversal idea will be utilized. The wave focusing ability of the developed PMPT array is tested with multiple-crack detection experiments. Imaging of localized surface inspection regions is also attempted by using wave signals measured by the developed PMPT array system.

  10. Preparation of active 3D film patches via aligned fiber electrohydrodynamic (EHD) printing

    NASA Astrophysics Data System (ADS)

    Wang, Jun-Chuan; Zheng, Hongxia; Chang, Ming-Wei; Ahmad, Zeeshan; Li, Jing-Song

    2017-03-01

    The design, preparation and application of three-dimensional (3D) printed structures have gained appreciable interest in recent times, particularly for drug dosage development. In this study, the electrohydrodynamic (EHD) printing technique was developed to fabricate aligned-fiber antibiotic (tetracycline hydrochloride, TE-HCL) patches using polycaprolactone (PCL), polyvinyl pyrrolidone (PVP) and their composite system (PVP-PCL). Drug loaded 3D patches possessed perfectly aligned fibers giving rise to fibrous strut orientation, variable inter-strut pore size and controlled film width (via layering). The effect of operating parameters on fiber deposition and alignment were explored, and the impact of the film structure, composition and drug loading was evaluated. FTIR demonstrated successful TE-HCL encapsulation in aligned fibers. Patches prepared using PVP and TE-HCL displayed enhanced hydrophobicity. Tensile tests exhibited changes to mechanical properties arising from additive effects. Release of antibiotic from PCL-PVP dosage forms was shown over 5 days and was slower compared to pure PCL or PVP. The printed patch void size also influenced antibiotic release behavior. The EHDA printing technique provides an exciting opportunity to tailor dosage forms in a single-step with minimal excipients and operations. These developments are crucial to meet demands where dosage forms cannot be manufactured rapidly or when a personalized approach is required.

  11. Preparation of active 3D film patches via aligned fiber electrohydrodynamic (EHD) printing

    PubMed Central

    Wang, Jun-Chuan; Zheng, Hongxia; Chang, Ming-Wei; Ahmad, Zeeshan; Li, Jing-Song

    2017-01-01

    The design, preparation and application of three-dimensional (3D) printed structures have gained appreciable interest in recent times, particularly for drug dosage development. In this study, the electrohydrodynamic (EHD) printing technique was developed to fabricate aligned-fiber antibiotic (tetracycline hydrochloride, TE-HCL) patches using polycaprolactone (PCL), polyvinyl pyrrolidone (PVP) and their composite system (PVP-PCL). Drug loaded 3D patches possessed perfectly aligned fibers giving rise to fibrous strut orientation, variable inter-strut pore size and controlled film width (via layering). The effect of operating parameters on fiber deposition and alignment were explored, and the impact of the film structure, composition and drug loading was evaluated. FTIR demonstrated successful TE-HCL encapsulation in aligned fibers. Patches prepared using PVP and TE-HCL displayed enhanced hydrophobicity. Tensile tests exhibited changes to mechanical properties arising from additive effects. Release of antibiotic from PCL-PVP dosage forms was shown over 5 days and was slower compared to pure PCL or PVP. The printed patch void size also influenced antibiotic release behavior. The EHDA printing technique provides an exciting opportunity to tailor dosage forms in a single-step with minimal excipients and operations. These developments are crucial to meet demands where dosage forms cannot be manufactured rapidly or when a personalized approach is required. PMID:28272513

  12. Enhanced Stability of Inactivated Influenza Vaccine Encapsulated in Dissolving Microneedle Patches

    PubMed Central

    Chu, Leonard Y.; Ye, Ling; Dong, Ke; Compans, Richard W.; Yang, Chinglai; Prausnitz, Mark R.

    2015-01-01

    Purpose This study tested the hypothesis that encapsulation of influenza vaccine in microneedle patches increases vaccine stability during storage at elevated temperature. Methods Whole inactivated influenza virus vaccine (A/Puerto Rico/8/34) was formulated into dissolving microneedle patches and vaccine stability was evaluated by in vitro and in vivo assays of antigenicity and immunogenicity after storage for up to 3 months at 4, 25, 37 and 45°C. Results While liquid vaccine completely lost potency as determined by hemagglutination (HA) activity within 1–2 weeks outside of refrigeration, vaccine in microneedle patches lost 40–50% HA activity during or shortly after fabrication, but then had no significant additional loss of activity over 3 months of storage, independent of temperature. This level of stability required reduced humidity by packaging with desiccant, but was not affected by presence of oxygen. This finding was consistent with additional stability assays, including antigenicity of the vaccine measured by ELISA, virus particle morphological structure captured by transmission electron microscopy and protective immune responses by immunization of mice in vivo. Conclusions These data show that inactivated influenza vaccine encapsulated in dissolving microneedle patches has enhanced stability during extended storage at elevated temperatures. PMID:26620313

  13. Adherence of Staphylococcus aureus to Dyneema Purity® Patches and to Clinically Used Cardiovascular Prostheses

    PubMed Central

    Basir, Amir; Gründeman, Paul; Moll, Frans; van Herwaarden, Joost; Pasterkamp, Gerard

    2016-01-01

    Various materials that are used for vascular and heart valve prostheses carry drawbacks: some require anticoagulant drugs or have moderate durability; others are not suitable for endovascular treatment. These prostheses are associated with bacterial infections. A material potentially suitable for prostheses is Dyneema Purity®, made of ultra—high-molecular-weight polyethylene. Dyneema Purity® fibers are very thin, flexible, resistant to fatigue and abrasion, and have high strength. S. aureus adherence to Dyneema Purity® was tested and compared with currently used cardiovascular prostheses. We compared adhesion of S. aureus to Dyneema Purity® (1 membrane-based and 1 yarn-composed patch) with 5 clinically used yarn-composed polyester and membrane-based expanded polytetrafluoroethylene patches. Patches were contaminated with S. aureus bacteria and bacterial adherence was quantified. S. aureus adherence was also visualized in flow conditions. Overall, bacterial adherence was higher on yarn-composed prosthesis materials, with a rough surface, than on the membrane-based materials, with a smooth surface. Adherence to Dyneema Purity® materials was non-inferior to the currently used materials. Therefore, patches of Dyneema Purity® might be attractive for use in cardiovascular applications such as catheter-based heart valves and endovascular prostheses by their good mechanical properties combined with their noninferiority regarding bacterial adhesion. PMID:27583703

  14. Preparation of active 3D film patches via aligned fiber electrohydrodynamic (EHD) printing.

    PubMed

    Wang, Jun-Chuan; Zheng, Hongxia; Chang, Ming-Wei; Ahmad, Zeeshan; Li, Jing-Song

    2017-03-08

    The design, preparation and application of three-dimensional (3D) printed structures have gained appreciable interest in recent times, particularly for drug dosage development. In this study, the electrohydrodynamic (EHD) printing technique was developed to fabricate aligned-fiber antibiotic (tetracycline hydrochloride, TE-HCL) patches using polycaprolactone (PCL), polyvinyl pyrrolidone (PVP) and their composite system (PVP-PCL). Drug loaded 3D patches possessed perfectly aligned fibers giving rise to fibrous strut orientation, variable inter-strut pore size and controlled film width (via layering). The effect of operating parameters on fiber deposition and alignment were explored, and the impact of the film structure, composition and drug loading was evaluated. FTIR demonstrated successful TE-HCL encapsulation in aligned fibers. Patches prepared using PVP and TE-HCL displayed enhanced hydrophobicity. Tensile tests exhibited changes to mechanical properties arising from additive effects. Release of antibiotic from PCL-PVP dosage forms was shown over 5 days and was slower compared to pure PCL or PVP. The printed patch void size also influenced antibiotic release behavior. The EHDA printing technique provides an exciting opportunity to tailor dosage forms in a single-step with minimal excipients and operations. These developments are crucial to meet demands where dosage forms cannot be manufactured rapidly or when a personalized approach is required.

  15. Catch and Patch: A Pipette-Based Approach for Automating Patch Clamp That Enables Cell Selection and Fast Compound Application.

    PubMed

    Danker, Timm; Braun, Franziska; Silbernagl, Nikole; Guenther, Elke

    2016-03-01

    Manual patch clamp, the gold standard of electrophysiology, represents a powerful and versatile toolbox to stimulate, modulate, and record ion channel activity from membrane fragments and whole cells. The electrophysiological readout can be combined with fluorescent or optogenetic methods and allows for ultrafast solution exchanges using specialized microfluidic tools. A hallmark of manual patch clamp is the intentional selection of individual cells for recording, often an essential prerequisite to generate meaningful data. So far, available automation solutions rely on random cell usage in the closed environment of a chip and thus sacrifice much of this versatility by design. To parallelize and automate the traditional patch clamp technique while perpetuating the full versatility of the method, we developed an approach to automation, which is based on active cell handling and targeted electrode placement rather than on random processes. This is achieved through an automated pipette positioning system, which guides the tips of recording pipettes with micrometer precision to a microfluidic cell handling device. Using a patch pipette array mounted on a conventional micromanipulator, our automated patch clamp process mimics the original manual patch clamp as closely as possible, yet achieving a configuration where recordings are obtained from many patch electrodes in parallel. In addition, our implementation is extensible by design to allow the easy integration of specialized equipment such as ultrafast compound application tools. The resulting system offers fully automated patch clamp on purposely selected cells and combines high-quality gigaseal recordings with solution switching in the millisecond timescale.

  16. Development and characterization of Eudragit based mucoadhesive buccal patches of salbutamol sulfate

    PubMed Central

    Vasantha, Prasanth Viswanadhan; Puratchikody, Ayarivan; Mathew, Sam Thomarayil; Balaraman, Ashok Kumar

    2011-01-01

    For systemic drug delivery, the buccal region offers an attractive route of drug administration. Salbutamol sulfate is a short-acting β2-adrenergic receptor agonist used for the relief of bronchospasm in conditions such as asthma and chronic obstructive pulmonary disease. It’s oral bioavailability is ∼40% due to extensive first pass metabolism. Salbutamol sulfate patches were prepared using Eudragit L-100, HPMC, PVA and Carbopol 934 in various proportions and combinations using PEG-400/PG as plasticizers. Patches were laminated on one side with a water impermeable backing layer for unidirectional drug release. The thickness of medicated patches were ranged between 0.23 ± 0.008 and 0.59 ± 0.007 mm and mass varied between 65.23 ± 3.3 and 117.92 ± 4.2 mg. Patches showed an increase in mass and swelling index with PEG-400 when compared with PG. The surface-pH of patches ranged between 6 and 7. Formulations E7 (7.5 mL Eudragit L-100, 15 mL HPMC K4M, 7.5 mL PVA and 2 mL PEG-400), E12 (7.5 mL Eudragit L-100, 7.5 mL PVA, 15 mL Carbopol and 2 mL PEG-400), F7 (7.5 mL Eudragit L-100, 15 mL HPMC K4M, 7.5 mL PVA and 2 mL PG), and F12 (7.5 mL Eudragit L-100, 7.5 mL PVA, 15 mL Carbopol and 2 mL PG) showed high folding endurance. Residence time of the tested patches ranged between 101 and 110 min. The maximum in vitro release was found to be 99.93% over a period of 120 min for formulation F12. Data of in vitro release from patches were fitted to different kinetic models such as Higuchi and Korsmeyer–Peppas models to explain the release profile. Formulations E7 and F7 were best fitted to the non-Fickian, where as formulations E12 and F12 showed Fickian/anomalous drug release. Stability studies indicated that there was no change in the chemical and physical characteristics during the test period. PMID:23960761

  17. Relative importance of host plant patch geometry and habitat quality on the patterns of occupancy, extinction and density of the monophagous butterfly Iolana iolas.

    PubMed

    Rabasa, Sonia G; Gutiérrez, David; Escudero, Adrián

    2008-06-01

    Habitat fragmentation is a major cause of species rarity and decline because it increases local population extinctions and reduces recolonisation rates of remnant patches. Although two major patch characteristics (area and connectivity) have been used to predict distribution patterns in fragmented landscapes, other factors can affect the occurrence of a species as well as the probability of it becoming extinct. In this paper, we study the spatial structure and dynamics of the butterfly Iolana iolas in a 75-patch network of its host plant (Colutea hispanica) to determine the relative importance of patch area, connectivity and habitat quality characteristics on occupancy, extinction and density over the period 2003-2006. Occupancy in 2003, incidence (proportion of years occupied) and probability of extinction were mostly affected by patch area. Smaller patches were less likely to be occupied because they had a higher probability of extinction, partly due to environmental stochasticity. The density of I. iolas was negatively related to patch area in all study years. Only in 2004 was the density of I. iolas positively influenced by fruit production per plant. Our results suggest that for I. iolas, and probably for other specialist butterflies with clearly delimited resource requirements, metapopulation dynamics can be satisfactorily predicted using only geometric variables because most habitat characteristics are subsumed in patch area. However, this hypothesis should be subject to further testing under diverse environmental conditions to evaluate the extent of its generalisation.

  18. Temporal characteristics and energy deposition of pulsating auroral patches

    NASA Astrophysics Data System (ADS)

    Humberset, B. K.; Gjerloev, J. W.; Samara, M.; Michell, R. G.; Mann, I. R.

    2016-07-01

    We present a careful statistical analysis of pulsating aurora (PA) using all-sky green line (557.7 nm) images obtained at 3.3 Hz. Six well-defined individual PA patches are identified and extracted using a contouring technique. Quantitative parameters such as the patch duration (on-time and off-time), peak intensity, and integrated intensity are determined for each patch and each pulsation. The resulting characteristics serve as strict observational constraints that any of the many competing theories attempting to explain PA must predict. The purpose of this paper is to determine the characteristics of PA patches in order to provide better observational constraints on the suggested mechanisms. All aspects of the temporal behavior of the individual patches appear to be erratic. Historically, PA has been defined very loosely and we argue that the use of the term "pulsating" is inappropriate since our findings and other published results are not regularly periodic and thus a more appropriate term may be fluctuating aurora. Further, we find that the observational constraints do not fit well with the flow cyclotron maser theory, which in particular is suggested to create PA patches. There is no clear candidate of the suggested mechanisms and drivers to explain the observational constraints set by the PA patches in a satisfactory manner.

  19. An Algorithm for Projecting Points onto a Patched CAD Model

    SciTech Connect

    Henshaw, W D

    2001-05-29

    We are interested in building structured overlapping grids for geometries defined by computer-aided-design (CAD) packages. Geometric information defining the boundary surfaces of a computation domain is often provided in the form of a collection of possibly hundreds of trimmed patches. The first step in building an overlapping volume grid on such a geometry is to build overlapping surface grids. A surface grid is typically built using hyperbolic grid generation; starting from a curve on the surface, a grid is grown by marching over the surface. A given hyperbolic grid will typically cover many of the underlying CAD surface patches. The fundamental operation needed for building surface grids is that of projecting a point in space onto the closest point on the CAD surface. We describe an fast algorithm for performing this projection, it will make use of a fairly coarse global triangulation of the CAD geometry. We describe how to build this global triangulation by first determining the connectivity of the CAD surface patches. This step is necessary since it often the case that the CAD description will contain no information specifying how a given patch connects to other neighboring patches. Determining the connectivity is difficult since the surface patches may contain mistakes such as gaps or overlaps between neighboring patches.

  20. Temporal Characteristics and Energy Deposition of Pulsating Auroral Patches

    NASA Technical Reports Server (NTRS)

    Humberset, B. K.; Gjerloev, J. W.; Samara, M.; Michell, R. G.; Mann, I. R.

    2016-01-01

    We present a careful statistical analysis of pulsating aurora (PA) using all-sky green line (557.7 nm) images obtained at 3.3 Hz. Six well-defined individual PA patches are identified and extracted using a contouring technique. Quantitative parameters such as the patch duration (on-time and off-time), peak intensity, and integrated intensity are determined for each patch and each pulsation. The resulting characteristics serve as strict observational constraints that any of the many competing theories attempting to explain PA must predict. The purpose of this paper is to determine the characteristics of PA patches in order to provide better observational constraints on the suggested mechanisms. All aspects of the temporal behavior of the individual patches appear to be erratic. Historically, PA has been defined very loosely and we argue that the use of the term pulsating is inappropriate since our findings and other published results are not regularly periodic and thus a more appropriate term may be fluctuating aurora. Further, we find that the observational constraints do not fit well with the flow cyclotron maser theory, which in particular is suggested to create PA patches. There is no clear candidate of the suggested mechanisms and drivers to explain the observational constraints set by the PA patches in a satisfactory manner.

  1. Heterogeneous iris image hallucination using sparse representation on a learned heterogeneous patch dictionary

    NASA Astrophysics Data System (ADS)

    Li, Yung-Hui; Zheng, Bo-Ren; Ji, Dai-Yan; Tien, Chung-Hao; Liu, Po-Tsun

    2014-09-01

    Cross sensor iris matching may seriously degrade the recognition performance because of the sensor mis-match problem of iris images between the enrollment and test stage. In this paper, we propose two novel patch-based heterogeneous dictionary learning method to attack this problem. The first method applies the latest sparse representation theory while the second method tries to learn the correspondence relationship through PCA in heterogeneous patch space. Both methods learn the basic atoms in iris textures across different image sensors and build connections between them. After such connections are built, at test stage, it is possible to hallucinate (synthesize) iris images across different sensors. By matching training images with hallucinated images, the recognition rate can be successfully enhanced. The experimental results showed the satisfied results both visually and in terms of recognition rate. Experimenting with an iris database consisting of 3015 images, we show that the EER is decreased 39.4% relatively by the proposed method.

  2. Patching rainfall data using regression methods. 3. Grouping, patching and outlier detection

    NASA Astrophysics Data System (ADS)

    Pegram, Geoffrey

    1997-11-01

    Rainfall data are used, amongst other things, for augmenting or repairing streamflow records in a water resources analysis environment. Gaps in rainfall records cause problems in the construction of water-balance models using monthly time-steps, when it becomes necessary to estimate missing values. Modest extensions are sometimes also desirable. It is also important to identify outliers as possible erroneous data and to group data which are hydrologically similar in order to accomplish good patching. Algorithms are described which accomplish these tasks using the covariance biplot, multiple linear regression, singular value decomposition and the pseudo-Expectation-Maximization algorithm.

  3. Dual-Band Miniaturized Patch Antennas for Microwave Breast Imaging

    PubMed Central

    Al-Joumayly, Mudar A.; Aguilar, Suzette M.; Behdad, Nader; Hagness, Susan C.

    2010-01-01

    We present a miniaturized, dual-band patch antenna array element that is designed for use in a 3-D microwave tomography system for breast imaging. Dual-band operation is achieved by manipulating the fundamental resonant mode of the patch antenna and one of its higher-order modes. Miniaturization and tuning of the resonant frequencies are achieved by loading the antenna with non-radiating slots at strategic locations along the patch. This results in a compact, dual-band antenna with symmetric radiation patterns and similar radiation characteristics at both bands of operation. The performance of the antenna in a biocompatible immersion medium is verified experimentally. PMID:21866218

  4. Dendritic Actin Filament Nucleation Causes Traveling Waves and Patches

    PubMed Central

    Carlsson, Anders E

    2010-01-01

    The polymerization of actin via branching at a cell membrane containing nucleation-promoting factors (NPFs) is simulated using a stochastic-growth methodology. The polymerized-actin distribution displays three types of behavior: a) traveling waves, b) moving patches, and c) random fluctuations. Increasing actin concentration causes a transition from patches to waves. The waves and patches move by a treadmilling mechanism which does not require myosin II. The effects of downregulation of key proteins on actin wave behavior are evaluated. PMID:20867207

  5. Direct Observations of the Evolution of Polar Cap Ionization Patches

    NASA Astrophysics Data System (ADS)

    Zhang, Q.; Zhang, B.; Lockwood, M. M.; Hu, H.; Moen, J. I.; Ruohoniemi, J.; Thomas, E. G.; Zhang, S.; Yang, H.; Liu, R.; McWilliams, K. A.; Baker, J. B.

    2013-12-01

    Patches of ionization are common in the polar ionosphere where their motion and associated density gradients give variable disturbances to High Frequency (HF) radio communications, over-the-horizon radar location errors, and disruption and errors to satellite navigation and communication. Their formation and evolution are poorly understood, particularly under disturbed space weather conditions. We report direct observations of the full evolution of patches during a geomagnetic storm, including formation, polar cap entry, transpolar evolution, polar cap exit, and sunward return flow. Our observations show that modulation of nightside reconnection in the substorm cycle of the magnetosphere helps form the gaps between patches where steady convection would give a 'tongue' of ionization (TOI).

  6. Esophageal Rings and Stricture Related to a Circumferential Inlet Patch

    PubMed Central

    Scott, Larry

    2016-01-01

    Inlet patches are sometimes seen during upper endoscopy, usually in the proximal esophagus. Complications of inlet patches can cause a wide array of symptoms and complications. A man presented with dysphagia and was found to have 2 rings in the upper esophagus, just above and below a circumferential inlet patch. The more distal ring caused a stenosis, which produced the symptoms. Savary dilation and treatment with a proton pump inhibitor led to symptom resolution. Pathology was missed on the patient's first endoscopy, highlighting the importance of looking for pathology throughout the entire esophagus, not just in the distal esophagus. PMID:27807576

  7. Structural Durability of Damaged Metallic Panel Repaired with Composite Patches

    NASA Technical Reports Server (NTRS)

    Minnetyan, Levon; Chamis, Christos C.

    1997-01-01

    Structural durability/damage tolerance characteristics of an aluminum tension specimen possessing a short crack and repaired by applying a fiber composite surface patch is investigated via computational simulation. The composite patch is made of graphite/epoxy plies with various layups. An integrated computer code that accounts for all possible failure modes is utilized for the simulation of combined fiber-composite/aluminum structural degradation under loading. Damage initiation, growth, accumulation, and propagation to structural fracture are included in the simulation. Results show the structural degradation stages due to tensile loading and illustrate the use of computational simulation for the investigation of a composite patch repaired cracked metallic panel.

  8. Multi-band CRLH unit cell -loaded patch antenna

    NASA Astrophysics Data System (ADS)

    El-Henawy, Sally I.; Omar, Ahmed A.; Safwat, Amr M. E.; El-Hennawy, Hadia S.

    2017-01-01

    A multi-band patch antenna loaded with composite right-/left-handed (CRLH) unit cell is presented in this paper. It operates at three bands, which are not harmonically related, covering several communication standards. The first and third bands have patch-like radiation pattern, and the second band has monopole-like radiation pattern. These bands can be controlled by varying the patch size and unit cell element values. The performance was analyzed using both electromagnetic and circuit simulations; furthermore, measurements were taken and all were in good agreement.

  9. Detection of coliforms in drinking water using skin patches: a rapid, reliable method that does not require an external energy source.

    PubMed

    Nam, Sehee; Kim, Min-jeong; Park, MinSun; Kim, Nuri; Lee, Yu-jin; Lee, Gyu-Cheol

    2014-02-01

    The detection of coliforms requires incubation in a laboratory, generally powered using electricity. In many parts of the developing world, however, external energy sources such as electricity are not readily available. To develop a fast, reliable method for detecting coliforms in water without an external energy source, we assessed the efficacy of six test kits for the identification of coliforms in water samples. To assess the possibility of using body temperature as the sole source of heat for incubation, bacterial samples were then mixed with the enzymatic test kit reagent and attached to the human body surface using a patch system. The patches were attached to the bodies of volunteers for 24 hours and the practicality and accuracy of the patches were assessed. Coliforms were detected within 24 hours in all patches. This innovation will facilitate the testing of water quality by researchers and by economically disadvantaged people without electricity.

  10. Alzheimer's Patients' Use of Painkilling Patches Cause for Concern

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_162442.html Alzheimer's Patients' Use of Painkilling Patches Cause for Concern Researchers ... opioid painkillers may be common among Alzheimer's disease patients and could be a cause for concern, researchers ...

  11. Self-focusing dynamics of patches of ripples

    NASA Astrophysics Data System (ADS)

    Milewski, P. A.; Wang, Z.

    2016-10-01

    The dynamics of focussing of extended patches of nonlinear capillary-gravity waves within the primitive fluid dynamic equations is presented. It is found that, when the envelope has certain properties, the patch focusses initially in accordance to predictions from nonlinear Schrödinger equation, and focussing can concentrate energy to the vicinity of a point or a curve on the fluid surface. After initial focussing, other effects dominate and the patch breaks up into a complex set of localised structures-lumps and breathers-plus dispersive radiation. We perform simulations both in the inviscid regime and for small viscosities. Lastly we discuss throughout the similarities and differences between the dynamics of ripple patches and self-focussing light beams.

  12. MULTISTAGE CHARACTERIZATION OF RIPARIAN PATCHES IN THE ARID SOUTHWEST

    EPA Science Inventory

    Some ecologically critical riparian ecosystems in the and Southwest are spatially and temporally discontinuous making their location and/or condition difficult to distinguish when studying the desert landscape. When conditions permit, riparian patches in the desert are distinct b...

  13. Polarization Reconfigurable Patch Antenna Using Microelectromechanical Systems (MEMS) Actuators

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Chun, Donghoon; Katehi, Linda P. B.

    2002-01-01

    The paper demonstrates a nearly square patch antenna integrated with a novel microelectromechanical systems (MEMS) actuator for reconfiguring the polarization. Experimental results demonstrate that at a fixed frequency, the polarization can be reconfigured, from circular to linear.

  14. Broadband Plasmonic Microlenses based on Patches of Nanoholes

    PubMed Central

    Gao, Hanwei; Hyun, Jerome K.; Lee, Min Hyung; Yang, Jiun-Chan; Lauhon, Lincoln J.; Odom, Teri W.

    2010-01-01

    This paper reports a new type of diffractive microlens based on finite-areas of 2D arrays of circular nanoholes (patches). The plasmonic microlenses can focus single wavelengths of light across the entire visible spectrum as well as broadband white light with little divergence. The focal length is determined primarily by the overall size of the patch and is tolerant to significant changes in patch substructure, including lattice geometry and local order of the circular nanoholes. The optical throughput, however, depends sensitively on the patch substructure and is determined by the wavelengths of surface plasmon resonances. This simple diffractive lens design enables millions of broadband plasmonic microlenses to be fabricated in parallel using soft nanolithographic techniques. PMID:20839781

  15. Combined Hormonal Birth Control: Pill, Patch, and Ring

    MedlinePlus

    ... FREQUENTLY ASKED QUESTIONS FAQ185 CONTRACEPTION Combined Hormonal Birth Control: Pill, Patch, and Ring • What are combined hormonal birth control methods? • How do combined hormonal methods prevent pregnancy? • ...

  16. Rain evaporation and moist patches in tropical boundary layers

    NASA Astrophysics Data System (ADS)

    Torri, Giuseppe; Kuang, Zhiming

    2016-09-01

    Moist patches are areas in the subcloud layer characterized by a positive water vapor anomaly compared to the environment and are considered important in triggering new convective cells. A correct understanding of the origin of the water vapor in these patches is, thus, essential to improving existing convective parameterizations. Recent studies have addressed this problem and have shown that contrary to what was previously thought, the main source of water vapor in moist patches are surface latent heat fluxes, instead of rain evaporation. This manuscript offers a different perspective to the topic, focusing on the origin only of the water vapor that makes moist patches anomalously moist when compared to the environment. It is found that near the surface, rain evaporation contributes half as much as latent heat fluxes, implying that a parameterization of the thermodynamic forcing should be more sensitive to environmental variables, like relative humidity, than recently suggested.

  17. Disorganized Cortical Patches Suggest Prenatal Origin of Autism

    MedlinePlus

    ... March 26, 2014 Disorganized cortical patches suggest prenatal origin of autism NIH-funded study shows disrupted cell ... treatments, and cures for both common and rare diseases. For more information about NIH and its programs, ...

  18. The individual element test revisited

    NASA Technical Reports Server (NTRS)

    Militello, Carmelo; Felippa, Carlos A.

    1991-01-01

    The subject of the patch test for finite elements retains several unsettled aspects. In particular, the issue of one-element versus multielement tests needs clarification. Following a brief historical review, we present the individual element test (IET) of Bergan and Hanssen in an expanded context that encompasses several important classes of new elements. The relationship of the IET to the multielement forms A, B, and C of the patch test and to the single element test are clarified.

  19. [Study on an optimized patch probe and its biomedical application].

    PubMed

    Yan, Liping; Huang, Kama; Liu, Changjun; Wang, Chengrong

    2006-12-01

    A wide-band patch probe excited by coaxial line, which is useful for noninvasive measurement of superficial tissues at high frequencies, is presented in this paper. Optimization of the probe is performed by genetic algorithm (GA) combined with Finite Difference Time Domain (FDTD). Then the optimized round patch probe is used to measure reflection coefficient for 1-7 GHz. The measured results show some interesting phenomena, which are very useful for reconstruction of electric properties of superficial tissues.

  20. Patch based recovery in finite element elastoplastic analysis

    NASA Astrophysics Data System (ADS)

    Daghia, Federica; de Miranda, Stefano; Ubertini, Francesco

    2013-10-01

    A new patch based stress recovery procedure for elastoplastic analysis is presented in this paper. The formulation derives from the extension to the elastic-perfectly plastic case of the Recovery by Compatibility in Patches procedure recently proposed by the authors. The present procedure is designed to simultaneously reconstruct both a new stress field and a new plastic strain field, so to ensure that elastoplastic consistency is satisfied. The numerical results on two common benchmark problems show the effectiveness of the new procedure.

  1. Evidence of sequentially formed charge patches guiding ions through nanocapillaries.

    PubMed

    Skog, P; Zhang, Hq; Schuch, R

    2008-11-28

    We investigated the time evolution of the dynamically shifting distribution of 7 keV Ne7+ ions guided through nanocapillaries in SiO2. We present evidence for a small number of charge patches, formed sequentially in the charging-up process, guiding the ions. We show that the charge patches are distributed along the whole length of the capillaries and that they are maintained in the equilibrium state of transmission. The interpretations are supported by model calculations.

  2. Histological and molecular-biological analyses of poly(3-hydroxybutyrate) (PHB) patches for enhancement of bone regeneration.

    PubMed

    Gredes, Tomasz; Gedrange, Tomasz; Hinüber, Claudia; Gelinsky, Michael; Kunert-Keil, Christiane

    2015-05-01

    Tissue engineered cell-seeded constructs with poly(3)hydroxybutyrate (PHB) induced ectopic bone formation after implantation into the back muscle of rats. The objective of our in vivo study was to evaluate the osteogenic potential of pure PHB patches in surgically created cranial defects. For this, PHB patches were analyzed after implantation in surgically created defects on the cranium of adult male rats. After healing periods of 4, 8 and 12 weeks, the bone tissue specimens containing PHB patches were processed and analyzed histologically as well as molecular-biologically. After 4 weeks, the PHB patches were completely embedded in connective tissue. Eight weeks after PHB insertion, bone regeneration proceeding from bearing bone was found in 50% of all treated animals, whereas all PHB treated cavities showed both bone formation and embedding of the patches in bone 12 weeks after surgery. Furthermore, all slices showed pronounced development of blood vessels. Histomorphometric analysis presented a regenerated bone mean value between 46.4 ± 16.1% and 54.2 ± 19.3% after 4-12 weeks of healing. Caveolin-1 staining in capillary-like structures showed a 1.16-1.38 fold increased expression in PHB treated defects compared to controls. Real-time RT-PCR analyses showed significantly lower expressions of Alpl, Col1a1 and VEGFA in cranium defects after treatment with PHB patches compared to untreated bony defects of the same cranium. Within the limits of the presented animal investigation, it could conclude that the tested PHB patches featured a good biocompatibility and an osteoconductive character.

  3. [The Cytoskelrtal Protein Zvxin Interacts with the Hedgehog Receptor Patched].

    PubMed

    Martynova, N U; Ermolina, L V; Eroshkin, F M; Zarayskiy, A G

    2015-01-01

    Earlier, we demonstrated Zyxin influence upon Hedgehog (Hh)-signaling pathway during early patterning of the central neural system (CNS) anlage of the Xenopus laevis embryo. Now we show that Zyxin can physically interact with the transmembrane receptor of Hh, Patched2 (Ptc2). Binding of Hh by this receptor activates signaling pathway, which regulates many events, including numerous types of cell differentiation during the embryonic development. In particular, patterning of the CNS anlage. The ability of Zyxin to interact with Ptc2 have been confirmed by immunoprecipitation experiments, in which we tested mutual binding affinity of Zyxin and Ptc2, as well as mutual affinity of their deletion mutants. As a result, we have established that in Xenopus levis, Zyxin binding to Ptc2 is due to the interaction of Zyxin 2nd LIM-domain (530-590 aa) with the under-membrane region of the cytoplasmic C-terminus of Ptc2 (1159-1412 aa). We have also demonstrated that similar interaction is valid for the homologous regions of the human Zyxin and human Hh receptor, Ptc1. The data obtained allow to hypothesize existence of evolutionary conserved mechanism that modulates Hh-signaling and based on the interaction of Zyxin with Ptc.

  4. Sound attenuation in ducts using locally resonant periodic aluminum patches.

    PubMed

    Farooqui, Maaz; Elnady, Tamer; Akl, Wael

    2016-06-01

    In recent years, the control of low frequency noise has received a lot of attention for several applications. Traditional passive noise control techniques using Helmholtz resonators have size limitations in the low frequency range because of the long wavelength. Promising noise reductions, with flush mounted aluminum patches with no size problems can be obtained using local resonance phenomenon implemented in acoustic metamaterial techniques. The objective of this work is to introduce locally resonant thin aluminum patches flush mounted to a duct walls aiming at creating frequency stop bands in a specific frequency range. Green's function is used within the framework of interface response theory to predict the amount of attenuation of the local resonant patches. The two-port theory and finite elements are also used to predict the acoustic performance of these patches. No flow measurements were conducted and show good agreement with the models. The effect of varying the damping and the masses of the patches are used to expand the stop bandwidth and the effect of both Bragg scattering and the locally resonant mechanisms was demonstrated using mathematical models. The effect of the arrays of patches on the effective dynamic density and bulk modulus has also been investigated.

  5. Application of monodirectional Janus patch to oromucosal delivery system.

    PubMed

    You, Jae Bem; Choi, Ah Young; Baek, Jieung; Oh, Myung Seok; Im, Sung Gap; Lee, Kyung Eun; Gwak, Hye Sun

    2015-10-28

    Drug delivery through mucosae has received huge research attention owing to its advantageous characteristics such as accurate dose control and the avoidance of premature metabolism of vulnerable drugs by oral administration. However, body fluid in mucosae may dissolve the drug, releasing it to unwanted directions. Here, a Janus drug delivery patch with monodirectional diffusion property is devised to deliver drugs efficiently and to overcome the issue of unwanted drug release. A polyester fabric is coated with a hydrophobic polymer, poly(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10-heptadecafluorodecyl methacrylate), via initiated chemical vapor deposition. Subsequently, hydrophilicity is rendered selectively on one surface by base-catalyzed hydrolysis to obtain a Janus substrate with both hydrophobic and hydrophilic surfaces. The hydrophilic surface of the Janus substrate is further coated with resveratrol-loaded hydrogel to produce a Janus drug delivery patch. The fabricated patch efficiently blocks fluid penetration from one side to the other in mucous environment. Delivery of resveratrol through hairless mouse skin and reconstructed human mucosae using Janus patch shows higher permeation flux compared to bare control patch. The Janus drug delivery patch shown in this study can be a useful tool for efficient transmucosal delivery of various kinds of drugs.

  6. Sessile Nanodroplets on Elliptical Patches of Enhanced Lyophilicity

    PubMed Central

    2017-01-01

    We theoretically investigate the shape of a nanodroplet on a lyophilic elliptical patch in lyophobic surroundings on a flat substrate. To compute the droplet equilibrium shape, we minimize its interfacial free energy using both Surface Evolver and Monte Carlo calculations, finding good agreement between the two methods. We observe different droplet shapes, which are controlled by the droplet volume and the aspect ratio of the ellipse. In particular, we study the behavior of the nanodroplet contact angle along the three-phase contact line, explaining the different droplet shapes. Although the nanodroplet contact angle is constant and fixed by Young’s law inside and outside the elliptical patch, its value varies along the rim of the elliptical patch. We find that because of the pinning of the nanodroplet contact line at the rim of the elliptical patch, which has a nonconstant curvature, there is a regime of aspect ratios of the elliptical patch in which the nanodroplet starts expanding to the lyophobic part of the substrate, although there is still a finite area of the lyophilic patch free to be wetted. PMID:28248114

  7. Guided bone regeneration using a flexible hydroxyapatite patch.

    PubMed

    Sun, Fangfang; Kang, Hyun Gu; Ryu, Su-Chak; Kim, Ji Eun; Park, Enoch Y; Hwang, Dae Youn; Lee, Jaebeom

    2013-11-01

    Guided bone regeneration (GBR) is a new method of promoting new bone formation by blocking the proliferation of regenerated connective tissue or providing additional interventions such as direct drug delivery and mechanical support. This in vivo study of bone regeneration in radius compound fractures in rabbits was conducted using a highly flexible scaffold of nanoscale hydroxyapatite (nHAp)/chitosan, termed a "bone patch". A solidification-assisted compression (SAC) method was utilized to fabricate the bone patch, and its in vivo cytotoxicity, bio-absorption, and bone regeneration capacity were evaluated. Four weeks after implantation, new bone formation with abundant active osteoblasts and incompleted degradation of chitosan in the patch were observed without any regeneration of connective tissue, compared with the corresponding implant without a patch. X-ray images showed that the radius with the bone patch had higher opacity than that of the control, which was consistent with the results obtained via histological analysis. Evidently, the nHAp-embedded bone-patch scaffold has considerable potential for application in the field of orthopedics of bone regeneration.

  8. Image Restoration using Prioritized Exemplar Inpainting with Automatic Patch Optimization

    NASA Astrophysics Data System (ADS)

    Borole, Rajesh Pandurang; Bonde, Sanjiv Vedu

    2016-08-01

    Image analysis and restoration has been carried out by texture synthesis for large regions and inpainting algorithms for small cracks in images. A new approach that allow simultaneous fill-in of different structures and textures is being proposed in present study. A combination of structure inpainting and patch-based texture synthesis with patch size optimization is carried out (termed as `optimized patch based inpainting') for filling and updating the target region that shows additional advantages over earlier approaches. The algorithm here uses the patch based inpainting having isophote driven patch-based texture synthesis at core. In present algorithm, ones the user selects the target regions, the algorithm automatically search and fills-in these regions with best matching information surrounding it. Patch-based filling is found to improve execution speed and robustness significantly over pixel-based fill. The fill-in is done in such a way that structure information arriving at the region boundaries is propagated inside. A number of examples on real and complex images are considered to demonstrate the effectiveness of the algorithm.

  9. The relationship between feeding rate and patch choice.

    PubMed Central

    Johnson, D F; Collier, G

    1991-01-01

    Rats in a laboratory foraging simulation searched for sequential opportunities to feed in two patches that differed in the rate at which food pellets were delivered (controlled by fixed-interval schedules) and in the size of the pellets. The profitability of feeding in each patch was calculated in terms of time (grams per minute) and in terms of effort (grams per bar press). These values were the result of the imposed fixed interval, the size of the pellets, and the rate at which the rats pressed the bar in each condition. The rats ate more food and larger meals, but not more frequent meals, at the patch offering the higher rate of food consumption, calculated as grams per minute. The relative intake at any patch was a function of the relative rate of intake during meals at that patch compared to the other patch. Rats respond to explicit manipulations of feeding time in the same manner as they respond to manipulations of feeding effort. PMID:2002303

  10. Successful application of large microneedle patches by human volunteers.

    PubMed

    Ripolin, Anastasia; Quinn, James; Larrañeta, Eneko; Vicente-Perez, Eva Maria; Barry, Johanne; Donnelly, Ryan F

    2017-02-16

    We describe, for the first time, the design, production and evaluation of large microneedle patches. Such systems, based on 16 individual microneedle arrays (needle height 600μm), were prepared from aqueous blends of 15% w/w Gantrez(®) S97 and 7.5% w/w poly(ethyleneglycol) 10,000Da. Ester-based crosslinking was confirmed by FTIR and mechanical strength was good. Insertion depths in a validated skin model were approximately 500μm. Ten human volunteers successfully self-inserted the microneedles of these larger patches in their skin, following appropriate instruction, as confirmed by transepidermal water loss measurements. The mean insertion depth ranged between 300 and 450μm over the area of the large patches. That this was not significantly different to a single unit MN patch self-applied by the same volunteers is encouraging. Microneedle patch sizes much larger than the 1-2cm(2) will be required if this technology is to be successfully translated to clinic for delivery of drug substances. The work described here suggests that use of such larger patches by patients can be successful, potentially opening up the possibility for a significant expansion of the size of the market for transdermal drug delivery.

  11. Clinical study of transcutaneous vaccination using a hydrogel patch for tetanus and diphtheria.

    PubMed

    Hirobe, Sachiko; Matsuo, Kazuhiko; Quan, Ying-Shu; Kamiyama, Fumio; Morito, Hironori; Asada, Hideo; Takaya, Yusuke; Mukai, Yohei; Okada, Naoki; Nakagawa, Shinsaku

    2012-02-27

    Transcutaneous immunization (TCI) is a non-invasive and easy-to-use vaccination method. We demonstrated the efficacy and safety of a transcutaneous vaccine formulation using a hydrogel patch in animal experiments. In the present study, we performed a clinical study to apply our TCI formulation for vaccination against tetanus and diphtheria in human. The TCI device was a hydrogel patch (antigen-free) applied to the left brachial medial skin of 22 healthy volunteers for 48 h. Next, the hydrogel patch, containing 2mg tetanus toxoid (TT) and 2mg diphtheria toxoid (DT) as the TCI formulation, was applied to 27 healthy volunteers for 24h and some volunteers were vaccinated again by TCI formulation. For safety assessment, the patch application site was observed to assess local adverse events, and systemic adverse events were determined by a blood test. The antigen-free hydrogel patch and TCI formulation containing TT and DT did not induce local or systemic severe adverse events. For vaccine efficacy estimation, toxoid-specific serum antibody titers were determined by ELISA and the toxin-neutralizing activity of the induced antibody was evaluated in a passive-challenge experiment. The anti-TT IgG titer and the anti-DT IgG titer increased, and a significant effect was detected by paired t-test. The antibody titers were maintained at higher level than that before vaccination for at least 1 year. Moreover, toxoid-specific antibodies were produced by the second vaccination in some subjects. Antibodies induced by application of the TCI formulation neutralized the toxin and prevented toxic death in mice. In addition, changes in the skin condition due to application of the TCI formulation were observed under in vivo confocal Raman spectroscopy. The amount of water and patch components in the stratum corneum increased after application of the TCI formulation, suggesting that the change in the skin condition was related to antigen penetration. These data indicate that this easy

  12. Superconducting antennas for telecommunication applications based on dual mode cross slotted patches

    NASA Astrophysics Data System (ADS)

    Cassinese, A.; Barra, M.; Fragalà, I.; Kusunoki, M.; Malandrino, G.; Nakagawa, T.; Perdicaro, L. M. S.; Sato, K.; Ohshima, S.; Vaglio, R.

    2002-08-01

    Dual mode devices based on high temperature superconducting films represent an interesting class for telecommunication applications since they combine a miniaturized size with a good power handling. Here we report on a novel compact antenna obtained by crossing a square patch with two or more slots. The proposed design has an antenna size reduction of about 40% as compared to the conventional square patch microstrip antennas. Single patch antenna both with linear (LP) and circular (CP) polarization operating in the X-band have been designed and tested at prototype level. They are realized by using double sided (YBa 2Cu 3O 7- x) YBCO and Tl 2Ba 2Ca 1Cu 2O 8 (Tl-2212) superconducting films grown on MgO substrates and tested with a portable cryocooler. They showed at T=77 K a return loss <25 dB and a power handling of 23 dBm. Exemplary 16 elements arrays LP antennas operating in the X band have been also realized by using YBCO film grown on 2 ″ diameter MgO substrate.

  13. A Spatial Landscape Model of Forest Patch Dynamics and Climate Change

    USGS Publications Warehouse

    Busing, Richard T.

    2007-01-01

    FOREL (a FOREst Landscape model) is an individual-based, multi-scale simulator of forest and climate dynamics. Rationale and design of the model are presented in relation to other forest patch models. Information on implementation of the model is also provided. Capabilities of the FOREL model are demonstrated for forest composition, structure and dynamics along climatic gradients. The model relies on a patch simulation approach that has been tested and developed by independent ecologists for more than three decades. Improvements made over the last decade to the simulation of climate effects on trees are incorporated in the landscape model. A single parameterization of the model is capable of simulating major shifts in forest composition and structure across broad climatic gradients. It is responsive along moisture gradients and temperature gradients. The landscape model is flexible and can be altered easily to test various assumptions about the effects of climate on trees, and the effects of spatial pattern on processes operating within and among forest stands. The spatial structure of the model makes interaction of patches possible. Interactions may include dispersal of propagules and competition for light. The model is a useful tool for projecting temporal climate change effects on forested sites, landscapes and regions.

  14. Male germ cell-specific expression of a novel Patched-domain containing gene Ptchd3

    SciTech Connect

    Fan Jun; Akabane, Hiroto; Zheng Xuehai; Zhou Xuan; Zhang Li; Liu Qiang; Zhang Yonglian; Yang Jing; Zhu Guozhang

    2007-11-23

    The Hedgehog (Hh) signaling pathway plays an important role in various biological processes, including pattern formation, cell fate determination, proliferation, and differentiation. Hh function is mediated through its membrane receptor Patched. Herein, we have characterized a novel Patched-domain containing gene Ptchd3 in mouse. Messenger RNA of Ptchd3 was exclusively detected in the testis, and existed in two isoforms Ptchd3a and Ptchd3b. The expression of these two mRNA isoforms was shown to be developmentally regulated in testes, and specifically found in male germ cells. Further analysis revealed that the Ptchd3 protein was located on the midpiece of mouse, rat and human sperm. Collectively, these results indicate that Ptchd3 is a novel male germ cell-specific gene and may be involved in the Hh signaling to regulate sperm development and/or sperm function.

  15. Combined patch containing salicylic acid and nicotinamide: role of drug interaction.

    PubMed

    Padula, Cristina; Ferretti, Chiara; Nicoli, Sara; Santi, Patrizia

    2010-12-01

    The aim of the present study was to formulate a combined patch containing salicylic (SA) acid and nicotinamide (NA), useful for the treatment of mild acne, and to verify their mutual effect on drug permeation and skin retention. The performance of the patch was tested in vitro in permeation experiments using pig ear skin as barrier. To better understand the data obtained from the film, permeation from solutions and isopropyl myristate/water partition coefficient were also determined. The results obtained in the present work suggest a mutual influence of NA and SA on their permeation across the skin from an innovative transdermal film. The partition coefficient obtained when the two molecules were simultaneously present was typically lower than the respective value obtained with NA and SA alone.

  16. Diclofenac epolamine (Flector) patch: evidence for topical activity.

    PubMed

    Petersen, Birte; Rovati, Stefano

    2009-01-01

    This review focuses on previously unpublished clinical and pharmacokinetic data with the diclofenac epolamine (diclofenac hydroxyethylpyrrolidine) patch supporting the hypothesis of a topical effect of this formulation. Previous studies have shown that 1 or 2 weeks of treatment with diclofenac epolamine provides pain relief for various localized musculoskeletal conditions such as ankle sprains, epicondylitis and knee osteoarthritis. The reduction in pain after application of the first patch in 155 patients with painful knee osteoarthritis was significant at the 1-hour time point and was superior to placebo at the 3-hour time point and at all time points thereafter. Comparable results were found in a study of 274 patients with acute ankle sprains, in which pain relief was also significantly superior to placebo at the 3-hour time point. Corresponding single-dose (patch) application for 12 hours in ten healthy volunteers demonstrated that diclofenac first appears in plasma at a mean of 4.5 hours after application (range 2-8 hours). Hence, the patch provided pain relief at a time point at which no diclofenac is assumed to be in plasma, which demonstrates local action in terms of tissue diclofenac accumulation under the patch. This is further supported by an apparent plasma diclofenac half-life of 9-12 hours after patch application, which implies the presence of a tissue reservoir, as the half-life after oral intake of diclofenac is 1-2 hours.Steady-state plasma diclofenac concentrations are present before 3 days' application (two patches/day) and are in the order of 1-3 ng/mL. The bioavailability in terms of systemic exposure from the patch compared with oral intake (75 mg/day) is in the order of 1%. Such low diclofenac concentrations are without systemic effects, as demonstrated by the fact that no drug-related gastrointestinal bleeding, ulcers or cutaneous events characteristic of Steven-Johnson syndrome have been reported during 15 years of diclofenac epolamine

  17. Paddle-pin alinement test

    NASA Technical Reports Server (NTRS)

    Gilliam, D. M.; Foster, J. A.

    1977-01-01

    Segmented insulated test bar speeds up patch distributor paddle-pin test. Device eliminates need to disconnect cables or remove distributor. Printed circuit cable and connector reduces weight on bar, adding to tester portability.

  18. Large-scale binding ligand prediction by improved patch-based method Patch-Surfer2.0

    PubMed Central

    Zhu, Xiaolei; Xiong, Yi; Kihara, Daisuke

    2015-01-01

    Motivation: Ligand binding is a key aspect of the function of many proteins. Thus, binding ligand prediction provides important insight in understanding the biological function of proteins. Binding ligand prediction is also useful for drug design and examining potential drug side effects. Results: We present a computational method named Patch-Surfer2.0, which predicts binding ligands for a protein pocket. By representing and comparing pockets at the level of small local surface patches that characterize physicochemical properties of the local regions, the method can identify binding pockets of the same ligand even if they do not share globally similar shapes. Properties of local patches are represented by an efficient mathematical representation, 3D Zernike Descriptor. Patch-Surfer2.0 has significant technical improvements over our previous prototype, which includes a new feature that captures approximate patch position with a geodesic distance histogram. Moreover, we constructed a large comprehensive database of ligand binding pockets that will be searched against by a query. The benchmark shows better performance of Patch-Surfer2.0 over existing methods. Availability and implementation: http://kiharalab.org/patchsurfer2.0/ Contact: dkihara@purdue.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25359888

  19. Novel speed-up strategies for non-local means denoising with patch and edge patch based dictionaries.

    PubMed

    Bhujle, Hemalata; Chaudhuri, Subhasis

    2014-01-01

    In this paper, a novel technique to speed-up a nonlocal means (NLM) filter is proposed. In the original NLM filter, most of its computational time is spent on finding distances for all the patches in the search window. Here, we build a dictionary in which patches with similar photometric structures are clustered together. Dictionary is built only once with high resolution images belonging to different scenes. Since the dictionary is well organized in terms of indexing its entries, it is used to search similar patches very quickly for efficient NLM denoising. We achieve a substantial reduction in computational cost compared with the original NLM method, especially when the search window of NLM is large, without much affecting the PSNR. Second, we show that by building a dictionary for edge patches as opposed to intensity patches, it is possible to reduce the dictionary size; thus, further improving the computational speed and memory requirement. The proposed method preclassifies similar patches with the same distance measure as used by NLM method. The proposed algorithm is shown to outperform other prefiltering based fast NLM algorithms computationally as well as qualitatively.

  20. Knowledge-based design of generate-and-patch problem solvers that solve global resource assignment problems

    NASA Technical Reports Server (NTRS)

    Voigt, Kerstin

    1992-01-01

    We present MENDER, a knowledge based system that implements software design techniques that are specialized to automatically compile generate-and-patch problem solvers that satisfy global resource assignments problems. We provide empirical evidence of the superior performance of generate-and-patch over generate-and-test: even with constrained generation, for a global constraint in the domain of '2D-floorplanning'. For a second constraint in '2D-floorplanning' we show that even when it is possible to incorporate the constraint into a constrained generator, a generate-and-patch problem solver may satisfy the constraint more rapidly. We also briefly summarize how an extended version of our system applies to a constraint in the domain of 'multiprocessor scheduling'.

  1. Embedding of Cortical Representations by the Superficial Patch System

    PubMed Central

    Da Costa, Nuno M. A.; Girardin, Cyrille C.; Naaman, Shmuel; Omer, David B.; Ruesch, Elisha; Grinvald, Amiram; Douglas, Rodney J.

    2011-01-01

    Pyramidal cells in layers 2 and 3 of the neocortex of many species collectively form a clustered system of lateral axonal projections (the superficial patch system—Lund JS, Angelucci A, Bressloff PC. 2003. Anatomical substrates for functional columns in macaque monkey primary visual cortex. Cereb Cortex. 13:15–24. or daisy architecture—Douglas RJ, Martin KAC. 2004. Neuronal circuits of the neocortex. Annu Rev Neurosci. 27:419–451.), but the function performed by this general feature of the cortical architecture remains obscure. By comparing the spatial configuration of labeled patches with the configuration of responses to drifting grating stimuli, we found the spatial organizations both of the patch system and of the cortical response to be highly conserved between cat and monkey primary visual cortex. More importantly, the configuration of the superficial patch system is directly reflected in the arrangement of function across monkey primary visual cortex. Our results indicate a close relationship between the structure of the superficial patch system and cortical responses encoding a single value across the surface of visual cortex (self-consistent states). This relationship is consistent with the spontaneous emergence of orientation response–like activity patterns during ongoing cortical activity (Kenet T, Bibitchkov D, Tsodyks M, Grinvald A, Arieli A. 2003. Spontaneously emerging cortical representations of visual attributes. Nature. 425:954–956.). We conclude that the superficial patch system is the physical encoding of self-consistent cortical states, and that a set of concurrently labeled patches participate in a network of mutually consistent representations of cortical input. PMID:21383233

  2. Structural Health Monitoring of a Bonded Composite Patch Repair on a Fatigue-Cracked F-111C Wing

    DTIC Science & Technology

    2008-03-01

    patched crack, there were some difficulties in reconciling the NDI and fractographic observations just prior to failure of the wing in the fatigue test ...29 6.2 Discussion of Results 6.2.1 Bond Strengths and Failure Modes Environmental degradation of the adhesive bond would be manifested in the test ...the bond test plugs are shown together with the bond strength in MPa and failure mode. The locations of strain gauge strips and single gauges are also

  3. Reproducible, high performance patch antenna array apparatus and method of fabrication

    DOEpatents

    Strassner, II, Bernd H.

    2007-01-23

    A reproducible, high-performance patch antenna array apparatus includes a patch antenna array provided on a unitary dielectric substrate, and a feed network provided on the same unitary substrate and proximity coupled to the patch antenna array. The reproducibility is enhanced by using photolithographic patterning and etching to produce both the patch antenna array and the feed network.

  4. [Maintenance capacity of plant community diversity of wetlands in patch scale].

    PubMed

    Sun, Xian-bin; Liu, Hong-yu; Zhang, Xiao-hong; Hu, Jun-na

    2009-03-01

    Based on GIS and principal component analysis method, this paper analyzed the relationships between the patch characteristics and the plant community diversity in the patches of wetlands in Naoli River Watershed in 1950, 1967, 1983 and 2000. The results showed that in 1950-2000, the average patch size of the wetlands and the number of the patches that had the capacity of maintaining more than two types of wetland plant community decreased dramatically, and the minimum patch size was 10.1 km2. Both the plant community diversity index and the number of plant community types had significant positive correlations with the patch size of the wetlands. The larger the patch size, the higher maintenance capacity of plant community diversity. With the decrease of patch size, the patch fragmentation index and patch fragmental dimension increased, while the patch shape index and the plant community diversity index in the patches decreased. With the increase of patch spatial separation, the plant community diversity index in the patches decreased. Principal component analysis indicated that patch size was the most important factor affecting the plant community diversity of wetlands, followed by patch fragmentation and separation.

  5. Patches with links: a unified system for processing faces in the macaque temporal lobe.

    PubMed

    Moeller, Sebastian; Freiwald, Winrich A; Tsao, Doris Y

    2008-06-06

    The brain processes objects through a series of regions along the ventral visual pathway, but the circuitry subserving the analysis of specific complex forms remains unknown. One complex form category, faces, selectively activates six patches of cortex in the macaque ventral pathway. To identify the connectivity of these face patches, we used electrical microstimulation combined with simultaneous functional magnetic resonance imaging. Stimulation of each of four targeted face patches produced strong activation, specifically within a subset of the other face patches. Stimulation outside the face patches produced an activation pattern that spared the face patches. These results suggest that the face patches form a strongly and specifically interconnected hierarchical network.

  6. Simultaneous shear and pressure sensing based on patch antenna

    NASA Astrophysics Data System (ADS)

    Jiang, Hao; Huang, Haiying

    2015-04-01

    In this paper, we presented a microstrip patch antenna sensor that is capable to measure the shear and normal deformations simultaneously. The sensor was designed based on the electromagnetic interference between a microstrip patch antenna and a metallic reflector separated by a distance. By placing the reflector on top of the patch antenna, the electromagnetic wave radiated by the patch antenna is reflected by the reflector and interferes with the electromagnetic field of the radiation patch, which in turn changes the antenna resonant frequencies. Since the antenna resonant frequencies are related to the lateral and vertical positions of the metallic reflector, the shear force and normal pressure that shift the reflector laterally and vertically can be detected by monitoring the antenna resonant frequencies. The numerical simulation and experimental measurements were carried out to evaluate the relationship between the antenna resonant frequencies and the shear and normal displacements. A data processing scheme was developed to inversely determine the shear and normal displacements from the antenna resonant frequencies.

  7. Nucleosomes determine their own patch size in base excision repair

    PubMed Central

    Meas, Rithy; Smerdon, Michael J.

    2016-01-01

    Base excision repair (BER) processes non-helix distorting lesions (e.g., uracils and gaps) and is composed of two subpathways that differ in the number of nucleotides (nts) incorporated during the DNA synthesis step: short patch (SP) repair incorporates 1 nt and long patch (LP) repair incorporates 2–12 nts. This choice for either LP or SP repair has not been analyzed in the context of nucleosomes. Initial studies with uracil located in nucleosome core DNA showed a distinct DNA polymerase extension profile in cell-free extracts that specifically limits extension to 1 nt, suggesting a preference for SP BER. Therefore, we developed an assay to differentiate long and short repair patches in ‘designed’ nucleosomes containing a single-nucleotide gap at specific locations relative to the dyad center. Using cell-free extracts or purified enzymes, we found that DNA lesions in the nucleosome core are preferentially repaired by DNA polymerase β and there is a significant reduction in BER polymerase extension beyond 1 nt, creating a striking bias for incorporation of short patches into nucleosomal DNA. These results show that nucleosomes control the patch size used by BER. PMID:27265863

  8. Modeling of endovascular patch welding using the computer program LATIS

    SciTech Connect

    Glinsky, M.E.; London, R.A.; Zimmerman, G.B.; Jacques, S.L.

    1995-03-01

    A new computer program, LATIS, being developed at Lawrence Livermore National Laboratory is used to study the effect of pulsed laser irradiation on endovascular patch welding. Various physical and biophysical effects are included in these simulations: laser light scattering and absorption, tissue heating and heat conduction, vascular cooling, and tissue thermal damage. The geometry of a patch being held against the inner vessel wall (500 {mu}m inner diameter) by a balloon is considered. The system is exposed to light pulsed from an optical fiber inside the balloon. A minimum in the depth of damage into the vessel wall is found. The minimum damage zone is about the thickness of the patch material that is heated by the laser. The more ordered the tissue the thinner the minimum zone of damage. The pulse length which minimizes the zone of damage is found to be the time for energy to diffuse across the layer. The delay time between the pulses is determined by the time for the heated layer to cool down. An optimal pulse length exists which minimizes the total time needed to weld the patch to the wall while keeping the thickness of the damaged tissue to less than 100 {mu}m. For the case that is considered, a patch dyed with light absorbing ICG on the side next to the vessel (thickness of the dyed layer is 60 {mu}m), the best protocol is found to be 65-200 ms pulses applied over 2 min.

  9. Polar cap patch transportation beyond the classic scenario

    NASA Astrophysics Data System (ADS)

    Zhang, Qing-He; Moen, Jøran; Lockwood, Michael; McCrea, Ian; Zhang, Bei-Chen; McWilliams, Kathryn A.; Zong, Qiu-Gang; Zhang, Shun-Rong; Ruohoniemi, J. Michael; Thomas, Evan G.; Dunlop, Malcolm W.; Liu, Rui-Yuan; Yang, Hui-Gen; Hu, Hong-Qiao; Lester, Mark

    2016-09-01

    We report the continuous monitoring of a polar cap patch, encompassing its creation, and a subsequent evolution that differs from the classic behavior. The patch was formed from the storm-enhanced density plume, by segmentation associated with a subauroral polarization stream generated by a substorm. Its initial antisunward motion was halted due to a rapidly changing of interplanetary magnetic field (IMF) conditions from strong southward to strong eastward with weaker northward components, and the patch subsequently very slowly evolved behind the duskside of a lobe reverse convection cell in afternoon sectors, associated with high-latitude lobe reconnection, much of it fading rapidly due to an enhancement of the ionization recombination rate. This differs from the classic scenario where polar cap patches are transported across the polar cap along the streamlines of twin-cell convection pattern from day to night. This observation provides us new important insights into patch formation and control by the IMF, which has to be taken into account in F region transport models and space weather forecasts.

  10. Front-Side Microstrip Line Feeding a Raised Antenna Patch

    NASA Technical Reports Server (NTRS)

    Hodges, Richard; Hoppe, Daniel

    2005-01-01

    An improved design concept for a printed-circuit patch antenna and the transmission line that feeds the patch calls for (1) a microstrip transmission line on the front (radiative) side of a printed-circuit board based on a thin, high-permittivity dielectric substrate; (2) using the conductor covering the back side of the circuit board as a common ground plane for both the microstrip line and the antenna patch; (3) supporting the antenna patch in front of the circuit board on a much thicker, lower-permittivity dielectric spacer layer; and (4) connecting the microstrip transmission line to the patch by use of a thin wire or narrow ribbon that extends through the thickness of the spacer and is oriented perpendicularly to the circuit-board plane. The thickness of the substrate is typically chosen so that a microstrip transmission line of practical width has an impedance between 50 and 100 ohms. The advantages of this design concept are best understood in the context of the disadvantages of prior design concepts, as explained

  11. Multiscale patterned transplantable stem cell patches for bone tissue regeneration.

    PubMed

    Kim, Jangho; Bae, Won-Gyu; Choung, Han-Wool; Lim, Ki Taek; Seonwoo, Hoon; Jeong, Hoon Eui; Suh, Khap-Yang; Jeon, Noo Li; Choung, Pill-Hoon; Chung, Jong Hoon

    2014-11-01

    Stem cell-based therapy has been proposed as an enabling alternative not only for the treatment of diseases but also for the regeneration of tissues beyond complex surgical treatments or tissue transplantation. In this study, we approached a conceptual platform that can integrate stem cells into a multiscale patterned substrate for bone regeneration. Inspired by human bone tissue, we developed hierarchically micro- and nanopatterned transplantable patches as synthetic extracellular matrices by employing capillary force lithography in combination with a surface micro-wrinkling method using a poly(lactic-co-glycolic acid) (PLGA) polymer. The multiscale patterned PLGA patches were highly flexible and showed higher tissue adhesion to the underlying tissue than did the single nanopatterned patches. In response to the anisotropically multiscale patterned topography, the adhesion and differentiation of human mesenchymal stem cells (hMSCs) were sensitively controlled. Furthermore, the stem cell patch composed of hMSCs and transplantable PLGA substrate promoted bone regeneration in vivo when both the micro- and nanotopography of the substrate surfaces were synergistically combined. Thus, our study concludes that multiscale patterned transplantable stem cell patches may have a great potential for bone regeneration as well as for various regenerative medicine approaches.

  12. The Value of Patch-Choice Copying in Fruit Flies

    PubMed Central

    Golden, Shane; Dukas, Reuven

    2014-01-01

    Many animals copy the choices of others but the functional and mechanistic explanations for copying are still not fully resolved. We relied on novel behavioral protocols to quantify the value of patch-choice copying in fruit flies. In a titration experiment, we quantified how much nutritional value females were willing to trade for laying eggs on patches already occupied by larvae (social patches). Females were highly sensitive to nutritional quality, which was positively associated with their offspring success. Females, however, perceived social, low-nutrition patches (33% of the nutrients) as equally valuable as non-social, high-nutrition ones (100% of the nutrients). In follow-up experiments, we could not, however, either find informational benefits from copying others or detect what females' offspring may gain from developing with older larvae. Because patch-choice copying in fruit flies is a robust phenomenon in spite of potential costs due to competition, we suggest that it is beneficial in natural settings, where fruit flies encounter complex dynamics of microbial communities, which include, in addition to the preferred yeast species they feed on, numerous harmful fungi and bacteria. We suggest that microbial ecology underlies many cases of copying in nature. PMID:25375776

  13. Rotigotine transdermal patch for the treatment of Parkinson's Disease.

    PubMed

    Perez-Lloret, Santiago; Rey, María Verónica; Ratti, Pietro Lucca; Rascol, Olivier

    2013-02-01

    Rotigotine, a non-ergot dopamine agonist, has been developed as a novel transdermal formulation. The rotigotine transdermal patch has received EMEA marketing authorization for the treatment of adult patients with early or advanced Parkinson's disease (PD) or with moderate to severe restless legs syndrome (RLS). FDA originally granted a marketing authorization for early PD, which was later suspended, and is now studying the authorization for RLS. The aim of this review is to review the pharmacokinetics, pharmacodynamics as well as the clinical efficacy and tolerability of the rotigotine transdermal patch in PD. Source material was identified using a PubMed search for the term 'rotigotine' and PD. Articles published up to January 2011 or abstract submitted to most relevant international neurology congresses were reviewed. The rotigotine transdermal patch is efficacious for the treatment of PD. Tolerability profile appears to be well within the range of that observed with other non-ergot dopamine agonists in PD. Application-site reactions were the most frequent adverse event, and they were considered mild to moderate in the majority of cases. The rotigotine transdermal patch offers a safe and efficacious alternative for the treatment of PD. Further studies should focus on the possibility that continuous dopamine stimulation by means of the transdermal patch has any influence on levodopa-related motor complications.

  14. Spatial patch occupancy patterns of the Lower Keys marsh rabbit

    USGS Publications Warehouse

    Eaton, Mitchell J.; Hughes, Phillip T.; Nichols, James D.; Morkill, Anne; Anderson, Chad

    2011-01-01

    Reliable estimates of presence or absence of a species can provide substantial information on management questions related to distribution and habitat use but should incorporate the probability of detection to reduce bias. We surveyed for the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) in habitat patches on 5 Florida Key islands, USA, to estimate occupancy and detection probabilities. We derived detection probabilities using spatial replication of plots and evaluated hypotheses that patch location (coastal or interior) and patch size influence occupancy and detection. Results demonstrate that detection probability, given rabbits were present, was <0.5 and suggest that naïve estimates (i.e., estimates without consideration of imperfect detection) of patch occupancy are negatively biased. We found that patch size and location influenced probability of occupancy but not detection. Our findings will be used by Refuge managers to evaluate population trends of Lower Keys marsh rabbits from historical data and to guide management decisions for species recovery. The sampling and analytical methods we used may be useful for researchers and managers of other endangered lagomorphs and cryptic or fossorial animals occupying diverse habitats.

  15. Host finding by Uscana lariophaga (Hymenoptera: Trichogrammatidae) in stored cowpea: the effect of distance, time interval, host patch size and spatial orientation.

    PubMed

    Stolk, C; Ghimire, M N; Souquié, S; van der Werf, W; van Huis, A

    2005-06-01

    Host finding and parasitization by Uscana lariophaga Steffan, a potential biocontrol agent of the storage pest Callosobruchus maculatus (Fabricius), were investigated in stored cowpea. Host finding was shown to be a function of distance, time, host patch size and the spatial position of U. lariophaga relative to the host patch. Uscana lariophaga females were able to find hosts up to 75 cm horizontal distance from the host patch, which was the largest distance tested. The probability that a host patch was found when an individual U. lariophaga female was released at 2.5 cm horizontal distance from the host patch ranged from 0.6 after 2 h foraging time to 0.9 after 8 h foraging time. At 10 cm from the host patch, host finding probability ranged from 0.2 to 0.45 at these respective foraging times. Finding probabilities doubled compared to horizontal distances when U. lariophaga was released below the host patch, and halved when it was released above the host patch. The negative geotaxic response was shown not to be an artefact of the release method. The median net displacement rate in the direction of the host patch was two beans per hour (1.4 cm h(-1)). The results suggest that U. lariophaga females start searching for hosts regardless of the quality of the olfactory information they receive. Additional observations indicated that U. lariophaga is adapted to a host with a patchy distribution, which implies that host finding over larger distances is relevant for U. lariophaga.

  16. Enterohemorrhagic Escherichia coli pathogenesis: role of Long polar fimbriae in Peyer’s patches interactions

    PubMed Central

    Cordonnier, Charlotte; Etienne-Mesmin, Lucie; Thévenot, Jonathan; Rougeron, Amandine; Rénier, Sandra; Chassaing, Benoit; Darfeuille-Michaud, Arlette; Barnich, Nicolas; Blanquet-Diot, Stéphanie; Livrelli, Valérie

    2017-01-01

    Enterohemorrhagic Escherichia coli (EHEC) are major food-borne pathogens whose survival and virulence in the human digestive tract remain unclear owing to paucity of relevant models. EHEC interact with the follicle-associated epithelium of Peyer’s patches of the distal ileum and translocate across the intestinal epithelium via M-cells, but the underlying molecular mechanisms are still unknown. Here, we investigated the involvement of Long polar fimbriae (Lpf) in EHEC pathogenesis. Of the 236 strains tested, a significant association was observed between the presence of lpf operons and pathogenicity. In sophisticated in vitro models of the human gastro-intestinal tract, lpf expression was induced during transit through the simulated stomach and small intestine, but not in the colonic compartment. To investigate the involvement of Lpf in EHEC pathogenesis, lpf isogenic mutants and their relative trans-complemented strains were generated. Translocation across M-cells, interactions with murine ileal biopsies containing Peyer’s patches and the number of hemorrhagic lesions were significantly reduced with the lpf mutants compared to the wild-type strain. Complementation of lpf mutants fully restored the wild-type phenotypes. Our results indicate that (i) EHEC might colonize the terminal ileum at the early stages of infection, (ii) Lpf are an important player in the interactions with Peyer’s patches and M-cells, and could contribute to intestinal colonization. PMID:28317910

  17. Skip entry guidance using numerical predictor-corrector and patched corridor

    NASA Astrophysics Data System (ADS)

    Luo, Zong-Fu; Zhang, Hong-Bo; Tang, Guo-Jian

    2015-12-01

    This paper presents a skip entry guidance algorithm that uses a numerical predictor-corrector and a patched corridor for low-lifting capsules returning from the Moon. The longitudinal and lateral channels are assumed to be decoupled. The bank angle magnitude profile is parameterized using piecewise linear segments with respect to a normalized energy. The shape of the bank-vs-energy profile is determined using a single piecewise-defined variable. The predicted longitudinal bias is nullified using a false position method. The adverse effects of aerodynamic and atmospheric uncertainties are mitigated using an on-board estimating strategy during the trajectory prediction. A patched corridor is devised to manage the lateral state based on analytical derivations and reasonable approximations. The sign of the bank angle is reversed when the boundary of the patched corridor is violated. Dispersed simulations are implemented in a three-degree-of-freedom dynamical context, and the results demonstrate the high performance of the proposed guidance algorithm under stressful testing conditions.

  18. Numerical comparison of patch and sandwich piezoelectric transducers for transmitting ultrasonic waves

    NASA Astrophysics Data System (ADS)

    Loveday, Philip W.

    2006-03-01

    Guided wave ultrasonic inspection is becoming an important method of non-destructive testing for long, slender structures such as pipes and rails. Often it is desirable to use transducers that can strongly excite a specific mode of wave propagation in the waveguide. Piezoelectric patch transducers are frequently employed, by researchers, for exciting waves in beam like structures. Sonar systems frequently make use of resonant transducers, such as sandwich transducers, for acoustic wave generation and this principle has been used to excite waves in a rail. This paper compares the two transduction approaches, for launching bending waves in rectangular waveguides, with numerical modeling. The numerical modeling combined a waveguide finite element model, of the waveguide, with conventional three-dimensional piezoelectric finite element models of the transducers. The waveguide finite elements were formulated using a complex exponential to describe the wave propagation along the structure and conventional finite element interpolation over the area of the element. Consequently, only a two-dimensional finite element mesh covering the cross-section of the waveguide is required. The harmonic forced response of the waveguide was used to compute a complex dynamic stiffness matrix which represented the waveguide in the transducer model. The effects of geometrical parameters of patch and sandwich transducers were considered before the comparison was made. It appears that piezoelectric patch transducers offer advantages at low frequencies while sandwich transducers are superior at high frequencies, where resonance can be exploited, at the cost of more complex design.

  19. Comparison of a Simple Patched Conic Trajectory Code to Commercially Available Software

    NASA Technical Reports Server (NTRS)

    AndersonPark, Brooke M.; Wright, Henry S.

    2007-01-01

    Often in spaceflight proposal development, mission designers must eva luate numerous trajectories as different design factors are investiga ted. Although there are numerous commercial software packages availab le to help develop and analyze trajectories, most take a significant amount of time to develop the trajectory itself, which isn't effectiv e when working on proposals. Thus a new code, PatCon, which is both q uick and easy to use, was developed to aid mission designers to condu ct trade studies on launch and arrival times for any given target pla net. The code is able to run quick analyses, due to the incorporation of the patched conic approximation, to determine the trajectory. PatCon provides a simple but accurate approximation of the four body moti on problem that would be needed to solve any planetary trajectory. P atCon has been compared to a patched conic test case for verification, with limited validation or comparison with other COTS software. This paper describes the patched conic technique and its implementation i n PatCon. A description of the results and comparison of PatCon to ot her more evolved codes such as AGI#s Satellite Tool Kit and JAQAR As trodynamics# Swingby Calculator is provided. The results will include percent differences in values such as C3 numbers, and Vinfinity at a rrival, and other more subjective results such as the time it takes to build the simulation, and actual calculation time.

  20. Patch-clamp evidence for calcium channels in apical membranes of rabbit kidney connecting tubules.

    PubMed Central

    Tan, S; Lau, K

    1993-01-01

    To test the hypothesis that Ca channel plays a role in renal epithelial Ca transport, we exposed and patched apical membranes of freshly microdissected rabbit connecting tubules (CNTs). Single channel Ca currents were recorded with Ba as the charge carrier. In the cell-attached mode, 8-Br-cAMP increased the open-state probability (Po) to 0.6%. In excised, inside-out patches, Po was low spontaneously and remained low during either bath protein kinase A catalytic subunit (PKAcs) or Bay K 8644. Exposure to both agonists, however, unmasked Ca channels previously latent with only one, raising Po by 1.05% at membrane potential of -70 mV. Mean Po for 14 seals (2.57%) peaked at -70 mV, declining with either hyperpolarization or depolarization. The slope conductance was 25 pS. The extrapolated reversal potential (138 mV) agrees with the calculated equilibrium potential for Ca (158 mV). The Ca to Na permeability ratio exceeded 2,800. In four patches stimulated by Bay K 8644 and PKAcs, bath nifedipine reduced Po from 1.03 to 0.15% at -63 mV. These patch-clamp data demonstrate a selective, 25-pS, cAMP/PKAcs-sensitive Ca channel in apical membranes of CNT. Po is stimulated by PKAcs and dihydropyridine (DHP) agonist, but inhibited by DHP antagonist and by depolarization. The data are consistent with the potential role of apical membrane Ca channel in epithelial Ca transport. PMID:7504693

  1. The role of vegetation patches and antecedent soil moisture conditions in runoff and erosion connectivity in a 4-times burnt pine stand.

    NASA Astrophysics Data System (ADS)

    Regensburg, Taco; González-Pelayo, Oscar; Martins, Martinho; Hosseini, Mohammedreza; Keesstra, Saskia; Keizer, Jan Jacob

    2015-04-01

    (50 cm x 50 cm); (ii) double inter-patch (50 cm x 100 cm); (iii) vegetation patch plus single upslope inter-patch (50 cm x 100 cm); (iv) vegetation patch plus double upslope inter-patch (50 cm x 150 cm). This experimental design was envisaged to address the following hypotheses: (i) runoff and erosion connectivity increase with increasing length of up-slope inter-patches; (ii) vegetation patches act as effective sinks of run-on and transported sediments from upslope inter-patches; (iii) the sink function of the vegetation patches is related to the influence of the shrubs on antecedent soil moisture conditions. The latter hypothesis is tested by means of replicate but unbounded plots next to the above-mentioned 150 cm-long bounded, being instrumented with EC-5 soil moisture sensors to automatically record topsoil moisture contents in a vegetation patch and upslope inter-patches. The very first results are pointing towards a confirmation of the first two of the above-mentioned hypotheses.

  2. Density of Diadema antillarum (Echinodermata: Echinoidea) on live coral patch reefs and dead Acropora cervicornis rubble patches near Loggerhead Key, Dry Tortugas National Park, Florida, USA

    EPA Science Inventory

    Density of adult Diadema antillarum was assessed on live coral patch reefs and dead Acropora cervicornis rubble patches next to Loggerhead Key, Dry Tortugas National Park, Florida, USA in June 2009. Mean density on live coral patch reefs (0.49 individuals m-2) was not statistical...

  3. Development of a novel prolonged-release nicotine transdermal patch.

    PubMed

    Davaran, Soodabeh; Rashidi, Mohammad R; Khandaghi, Reza; Hashemi, Mahdi

    2005-03-01

    A transdermal patch for delivering nicotine for periods of 12-48h was designed. An inclusion complex formed between the nicotine and beta-cyclodextrine (beta-CD) was used in drug depot. The usefulness of a specially cross-linked polyvinyl alcohol (cross-PVA) membrane was investigated as a rate controlling membrane. The influence of carbopol polymers, type C-934P and C-940 and propylene glycol on transdermal permeation of nicotine through the rat skin was investigated. The results indicated a maximum flux of 42 microgcm(-2)h(-1) after 48 h from the patches made from C-934P when the propylene glycol concentration was 15% and the nicotine-beta-CD mole ratio in the inclusion complex was 3:1. These nicotine transdermal patches can be fabricated to obtain a controlled release, zero order systems.

  4. Silicone Rubber Superstrate Loaded Patch Antenna Design Using Slotting Technique

    NASA Astrophysics Data System (ADS)

    Kaur, Bhupinder; Saini, Garima; Saini, Ashish

    2016-09-01

    For the protection of antenna from external environmental conditions, there is a need that antenna should be covered with a stable, non-reactive, highly durable and weather resistive material which is insensitive to changing external environment. Hence, in this paper silicone rubber is proposed as a superstrate layer for patch antenna for its protection. The electrical properties of silicon rubber sealant are experimentally found out and its effect of using as superstrate on coaxial fed microstrip patch antenna using transmission line model is observed. The overall performance is degraded by slightly after the use of superstrate. Further to improve the performance of superstrate loaded antenna, patch slots and ground defects have been proposed. The proposed design achieves the wideband of 790 MHz (13.59 %), gain of 7.12 dB, VSWR of 1.12 and efficiency of 83.02 %.

  5. Patch-based near-optimal image denoising.

    PubMed

    Chatterjee, Priyam; Milanfar, Peyman

    2012-04-01

    In this paper, we propose a denoising method motivated by our previous analysis of the performance bounds for image denoising. Insights from that study are used here to derive a high-performance practical denoising algorithm. We propose a patch-based Wiener filter that exploits patch redundancy for image denoising. Our framework uses both geometrically and photometrically similar patches to estimate the different filter parameters. We describe how these parameters can be accurately estimated directly from the input noisy image. Our denoising approach, designed for near-optimal performance (in the mean-squared error sense), has a sound statistical foundation that is analyzed in detail. The performance of our approach is experimentally verified on a variety of images and noise levels. The results presented here demonstrate that our proposed method is on par or exceeding the current state of the art, both visually and quantitatively.

  6. Shear sensing based on a microstrip patch antenna

    NASA Astrophysics Data System (ADS)

    Mohammad, I.; Huang, H.

    2012-10-01

    A microstrip patch antenna sensor was studied for shear sensing with a targeted application of measuring plantar shear distribution on a diabetic foot. The antenna shear sensor consists of three components, namely an antenna patch, a soft foam substrate and a slotted ground plane. The resonant frequency of the antenna sensor is sensitive to the overlapping length between the slot in the ground plane and the antenna patch. A shear force applied along the direction of the slot deforms the foam substrate and causes a change in the overlapping length, which can be detected from the antenna frequency shift. The antenna shear sensor was designed based on simulated antenna frequency response and validated by experiments. Experimental results indicated that the antenna sensor exhibits high sensitivity to shear deformation and responds to the applied shear loads with excellent linearity and repeatability.

  7. Patch-clamp experiments under micro-gravity.

    PubMed

    Meissner, Klaus; Hanke, Wolfgang

    2002-07-01

    For human based space research it is of high importance to understand the influence of gravity on the properties of single ion channels in biological membranes, as these are involved in about all biological processes. The patch clamp technique is the best established method to investigate electrophysiological properties of single ion channels in detail. Consequently, a patch clamp set-up was designed for the drop tower in Bremen, Germany. Using this set-up among others, successfully leech neurons have been patched under micro-gravity, delivering data about ion channel behaviour, which were compared to results from bilayer experiments in the drop tower and to results from lab controls under 1 g and under higher gravity.

  8. The Origin and Shape of Diffuse Auroral Patches

    NASA Technical Reports Server (NTRS)

    Rae, Kyle; Donovan, Eric; Liang, Jun; Spanswick, Emma L.; Lessard, Marc; Jones, Sarah; Jaynes, Allison N.

    2011-01-01

    Patchy pulsating aurora occurs commonly in the post-midnight sector. Recent studies have moved us significantly closer to understanding the mechanisms responsible for pitch angle scattering of the Central Plasma Sheet (CPS) electrons that produce these aurora. However, there is not yet an adequate explanation of what physical process gives rise to the patchy nature of the aurora. These patches last for minutes up to tens of minutes, with sizes that do not change significantly over their life time, and remain more or less stationary relative to the ground. In this paper, we use THEMIS and NORSTAR ASI observations of these auroral features to explore the shape of these patches. Based on our results, we conclude that the patches are the ionospheric counterpart of structures in cold plasma near the magnetospheric equator.

  9. Direct observations of the evolution of polar cap ionization patches.

    PubMed

    Zhang, Qing-He; Zhang, Bei-Chen; Lockwood, Michael; Hu, Hong-Qiao; Moen, Jøran; Ruohoniemi, J Michael; Thomas, Evan G; Zhang, Shun-Rong; Yang, Hui-Gen; Liu, Rui-Yuan; McWilliams, Kathryn A; Baker, Joseph B H

    2013-03-29

    Patches of ionization are common in the polar ionosphere, where their motion and associated density gradients give variable disturbances to high-frequency (HF) radio communications, over-the-horizon radar location errors, and disruption and errors to satellite navigation and communication. Their formation and evolution are poorly understood, particularly under disturbed space weather conditions. We report direct observations of the full evolution of patches during a geomagnetic storm, including formation, polar cap entry, transpolar evolution, polar cap exit, and sunward return flow. Our observations show that modulation of nightside reconnection in the substorm cycle of the magnetosphere helps form the gaps between patches where steady convection would give a "tongue" of ionization (TOI).

  10. Image superresolution of cytology images using wavelet based patch search

    NASA Astrophysics Data System (ADS)

    Vargas, Carlos; García-Arteaga, Juan D.; Romero, Eduardo

    2015-01-01

    Telecytology is a new research area that holds the potential of significantly reducing the number of deaths due to cervical cancer in developing countries. This work presents a novel super-resolution technique that couples high and low frequency information in order to reduce the bandwidth consumption of cervical image transmission. The proposed approach starts by decomposing into wavelets the high resolution images and transmitting only the lower frequency coefficients. The transmitted coefficients are used to reconstruct an image of the original size. Additional details are added by iteratively replacing patches of the wavelet reconstructed image with equivalent high resolution patches from a previously acquired image database. Finally, the original transmitted low frequency coefficients are used to correct the final image. Results show a higher signal to noise ratio in the proposed method over simply discarding high frequency wavelet coefficients or replacing directly down-sampled patches from the image-database.

  11. Formulation of Bilayer Benzydamine HCl Patch Targeted For Gingivitis

    PubMed Central

    Sanghai, Piyush; Poddar, Sushilkumar

    2016-01-01

    In the present study bilayer patch of benzydamine HCl was developed using solvent casting method. Different substrates were attempted like Petri dish, glass-and-ring, and teflon-and-ring for selection of the proper option to formulate patch that should give easily peelable film with adequate mechanical properties. HPMC E15 LV was used in different concentrations for obtaining proper viscosity of solution for pouring on to surface and ring, that it should not leak from ring. The second layer was optimized by using different polymer like eudragit RSPO, eudragit RSPO + EC, and eudragit NE30 D for efficient layer bonding. The minimum release from backing membrane was established by diffusion study as compared to from drug loaded layer. The optimized batches were evaluated for folding endurance, weight variation, thickness, drug content, drug release, tensile strength, layer separation, mucoadhesion, moisture uptake, and layer bonding. The novel gingival patch of benzydamine HCl developed would be beneficial in optimizing the therapy. PMID:28127472

  12. Recommended Practice for Patch Management of Control Systems

    SciTech Connect

    Steven Tom; Dale Christiansen; Dan Berrett

    2008-12-01

    A key component in protecting a nation’s critical infrastructure and key resources is the security of control systems. The term industrial control system refers to supervisory control and data acquisition, process control, distributed control, and any other systems that control, monitor, and manage the nation’s critical infrastructure. Critical Infrastructure and Key Resources (CIKR) consists of electric power generators, transmission systems, transportation systems, dam and water systems, communication systems, chemical and petroleum systems, and other critical systems that cannot tolerate sudden interruptions in service. Simply stated, a control system gathers information and then performs a function based on its established parameters and the information it receives. The patch management of industrial control systems software used in CIKR is inconsistent at best and nonexistent at worst. Patches are important to resolve security vulnerabilities and functional issues. This report recommends patch management practices for consideration and deployment by industrial control systems owners.

  13. Analysis of finite phased arrays of circular microstrip patches

    NASA Technical Reports Server (NTRS)

    Deshpande, Manohar D.; Bailey, Marion C.

    1989-01-01

    A method is presented for analyzing a finite planar array of circular microstrip patches fed by coaxial probes. The self- and mutual impedances between array elements are calculated using the method of moments with the dyadic Green's function for a dielectric layer on a ground plane. The patch circuits are determined by using the reaction integral equation. The active input impedance as well as the active element pattern of the array are computed from a knowledge of the resultant patch currents. The calculated results for two-element and eight-element linear arrays are in good agreement with experimental data. The active reflection coefficient and element pattern for the center and edge elements of a two-dimensional array as a function of scan angle are also presented.

  14. Evaluation of a tissue-engineered bovine pericardial patch in paediatric patients with congenital cardiac anomalies: initial experience with the ADAPT-treated CardioCel® patch

    PubMed Central

    Neethling, William M.L.; Strange, Geoff; Firth, Laura; Smit, Francis E.

    2013-01-01

    OBJECTIVES This study evaluated the safety, efficacy and clinical performance of the tissue-engineered ADAPT® bovine pericardial patch (ABPP) in paediatric patients with a range of congenital cardiac anomalies. METHODS In this single-centre, prospective, non-randomized clinical study, paediatric patients underwent surgery for insertion of the ABPP. Primary efficacy measures included early (<30 day) morbidity; incidence of device-related complications; haemodynamic performance derived from echocardiography assessment at 6- and 12-month follow-up and magnetic resonance imaging findings in 10 randomly selected patients at 12 months. Secondary measures included device-handling characteristics; shape and sizing characteristics and perioperative implant complications. The Aristotle complexity scoring system was used to score the complexity level of all surgical procedures. Patients completing the 12-month study were eligible to enter a long-term evaluation study. RESULTS Between April 2008 and September 2009, the ABPP was used in 30 paediatric patients. In the 30-day postoperative period, no graft-related morbidity was observed. In total, there were 5 deaths (2 in the 30-day postoperative period and 3 within the first 6 postoperative months). All deaths were deemed due to comorbid non-graft-related events. Echocardiography assessment at 6 and 12 months revealed intact anatomical and haemodynamically stable repairs without any visible calcification of the patch. Magnetic resonance imaging assessment in 10 patients at 12 months revealed no signs of calcification. Fisher's exact test demonstrated that patients undergoing more complex, higher risk surgical repairs (Aristotle complexity score >8) were significantly more likely to die (P = 0.0055, 58% survival compared with 100% survival for less complex surgical repairs). In 19 patients, echocardiographic data were available at 18–36 months with no evidence of device calcification, infection, thromboembolic events or

  15. Heterogeneous Light Supply Affects Growth and Biomass Allocation of the Understory Fern Diplopterygium glaucum at High Patch Contrast

    PubMed Central

    Guo, Wei; Song, Yao-Bin; Yu, Fei-Hai

    2011-01-01

    Spatial heterogeneity in resource supply is common and responses to heterogeneous resource supply have been extensively documented in clonal angiosperms but not in pteridophytes. To test the hypotheses that clonal integration can modify responses of pteridophytes to heterogeneous resource supply and the integration effect is larger at higher patch contrast, we conducted a field experiment with three homogeneous and two heterogeneous light treatments on the rhizomatous, understory fern Diplopterygium glaucum in an evergreen broad-leaved forest in East China. In homogeneous treatments, all D. glaucum ramets in 1.5 m×1.5 m units were subjected to 10, 40 and 100% natural light, respectively. In the heterogeneous treatment of low patch contrast, ramets in the central 0.5 m×0.5 m plots of the units were subjected to 40% natural light and their interconnected ramets in the surrounding area of the units to 100%; in the heterogeneous treatment of high patch contrast, ramets in the central plots were subjected to 10% natural light and those in the surrounding area to 100%. In the homogeneous treatments, biomass and number of living ramets in the central plots decreased and number of dead ramets increased with decreasing light supply. At low contrast heterogeneous light supply did not affect performance or biomass allocation of D. glaucum in the central plots, but at high contrast it increased lamina biomass and number of living ramets older than annual and modified biomass allocation to lamina and rhizome. Thus, clonal integration can affect responses of understory ferns to heterogeneous light supply and ramets in low light patches can be supported by those in high light. The results also suggest that effects of clonal integration depend on the degree of patch contrast and a significant integration effect may be found only under a relatively high patch contrast. PMID:22132189

  16. Predator-prey interactions, resource depression and patch revisitation

    USGS Publications Warehouse

    Erwin, R.M.

    1989-01-01

    Generalist predators may be confronted by different types of prey in different patches: sedentary and conspicuous, cryptic (with or without refugia), conspicuous and nonsocial, or conspicuous and social. I argue that, where encounter rates with prey are of most importance, patch revisitation should be a profitable tactic where prey have short 'recovery' times (conspicuous, nonsocial prey), or where anti-predator response (e.g. shoaling) may increase conspicuousness. Predictions are made for how temporal changes in prey encounter rates should affect revisit schedules and feeding rates for the 4 different prey types.

  17. A supervised patch-based approach for human brain labeling.

    PubMed

    Rousseau, Françcois; Habas, Piotr A; Studholme, Colin

    2011-10-01

    We propose in this work a patch-based image labeling method relying on a label propagation framework. Based on image intensity similarities between the input image and an anatomy textbook, an original strategy which does not require any nonrigid registration is presented. Following recent developments in nonlocal image denoising, the similarity between images is represented by a weighted graph computed from an intensity-based distance between patches. Experiments on simulated and in vivo magnetic resonance images show that the proposed method is very successful in providing automated human brain labeling.

  18. A supervised patch-based approach for human brain labeling

    PubMed Central

    Rousseau, François; Habas, Piotr A.; Studholme, Colin

    2012-01-01

    We propose in this work a patch-based image labeling method relying on a label propagation framework. Based on image intensity similarities between the input image and an anatomy textbook, an original strategy which does not require any non-rigid registration is presented. Following recent developments in non-local image denoising, the similarity between images is represented by a weighted graph computed from an intensity-based distance between patches. Experiments on simulated and in-vivo MR images show that the proposed method is very successful in providing automated human brain labeling. PMID:21606021

  19. Picosecond time of spontaneous emission in plasmonic patch nanoantennas

    NASA Astrophysics Data System (ADS)

    Eliseev, S. P.; Vitukhnovsky, A. G.; Chubich, D. A.; Kurochkin, N. S.; Sychev, V. V.; Marchenko, A. A.

    2016-01-01

    A significant (to 12 ps) decrease in the lifetime of excited states of quantum emitters in the form of three-layer colloidal quantum dots (CdSe/CdS/ZnS) placed in an aluminum-triangular silver nanoprism cavity (patch nanoantenna) has been experimentally demonstrated. The decrease in the time of spontaneous emission of quantum dots has been explained by the Purcell effect. The Purcell coefficient for an emitter in the resonator has been found to be 625. Such a significant increase in the rate of spontaneous emission in the patch nanoantenna is due to an increase in the local density of photon states in the plasmonic cavity.

  20. Formulation development and investigation of domperidone transdermal patches

    PubMed Central

    Prabhu, Prabhakar; Shah, Samip; Gundad, Shankar

    2011-01-01

    Aim and Background: Domperidone is a dopamine antagonist with antiemetic properties having a plasma half life of 7-9 h with 15% oral bioavailability. In the present work transdermal patches of domperidone were prepared with the objective to improve its therapeutic efficacy, patient compliance and to reduce the frequency of dosing and side effects, as well as to avoid its extensive first pass metabolism of the drug. Materials and Methods: The patches were prepared using ethyl cellulose (EC): Poly vinyl pyrrolidone (PVP), poly vinyl alcohol (PVA): Poly vinyl pyrrolidone (PVP) and hydroxypropylmethylcellulose (HPMC): Sodium (carboxy methyl cellulose) CMC as polymers in combination. The physicochemical parameters like thickness, drug content, weight variation, moisture absorption and drug permeation studies were evaluated for the prepared patches. No significant difference in thickness, average weight and in the drug content among the patches. Results: It was observed that from hydrophilic polymers the drug release was found to be faster compared to (F5 and F6 & F3 and F4) combination of hydrophilic and lipophilic polymers used in the study. Patches containing HPMC and Sodium CMC (F5 and F6) showed faster release as the patches showed maximum percentage amount moisture absorption. The in vitro release data was treated with kinetic equations and it followed Higuchi's diffusion mechanism. The in vivo bioavailability study was performed in rats and observed that, drug reached to the peak in approximately 60 min (16%) after oral route of administration. However, approximately same amount of drug was found in the serum from transdermal formulation in 6 h and further increase in the amount of drug in the serum, indicated that the drug 5 bioavailability could be better and hence the hepatic metabolism can be avoided, as it is evident from the data. Further, the decrease in the amount of drug present in the serum 45 min after oral administration also indicated that major

  1. Apollo 13 Astronaut Fred Haise and Apollo 13 Mission Patch

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Astronaut Fred Haise Jr. of Biloxi, Miss., views his Apollo 13 mission patch, the flight on which he served in 1970, in a StenniSphere display donated to NASA by the American Needlepoint Guild. The exhibit is on permanent display at StenniSphere, the visitor center at John C. Stennis Space Center. In its first year of operation, more than 251,000 visitors representing over 40 countries have viewed the 123 hand-stitched patches in the exhibit. Forty-two guild members from 20 states made the trip to StenniSphere for the opening of the exhibit, one of the most popular at StenniSphere.

  2. Patched1 and Patched2 inhibit Smoothened non-cell autonomously

    PubMed Central

    Roberts, Brock; Casillas, Catalina; Alfaro, Astrid C; Jägers, Carina; Roelink, Henk

    2016-01-01

    Smoothened (Smo) inhibition by Patched (Ptch) is central to Hedgehog (Hh) signaling. Ptch, a proton driven antiporter, is required for Smo inhibition via an unknown mechanism. Hh ligand binding to Ptch reverses this inhibition and activated Smo initiates the Hh response. To determine whether Ptch inhibits Smo strictly in the same cell or also mediates non-cell-autonomous Smo inhibition, we generated genetically mosaic neuralized embryoid bodies (nEBs) from mouse embryonic stem cells (mESCs). These experiments utilized novel mESC lines in which Ptch1, Ptch2, Smo, Shh and 7dhcr were inactivated via gene editing in multiple combinations, allowing us to measure non-cell autonomous interactions between cells with differing Ptch1/2 status. In several independent assays, the Hh response was repressed by Ptch1/2 in nearby cells. When 7dhcr was targeted, cells displayed elevated non-cell autonomous inhibition. These findings support a model in which Ptch1/2 mediate secretion of a Smo-inhibitory cholesterol precursor. DOI: http://dx.doi.org/10.7554/eLife.17634.001 PMID:27552050

  3. Assessment of patches attributes along the Urban Development Gradient

    NASA Astrophysics Data System (ADS)

    Kopel, Daniella; Wittenberg, lea; Malkinson, Dan

    2014-05-01

    The world is increasingly urban. If current trends maintain, by 2050 the global urban population is estimated to be 6.3 billion, nearly doubling the world population in 2010. Consequently, more than 60% of the area projected to be urban in 2030 has yet to be built, replacing the open and agriculture lands with construction and infrastructure. The open green patches (OGP), within the urban matrix, are essential for healthy and wellness of cities by supplying the city's ecological services (Mausback and Seybold, 1998). Regarding future trends, there is a need and obligation to insure the functional and sustainability of the city's OPG. Urban vegetation composition and diversity in the OGP had long been considered as an indication for ecologically functioning systems. Furthermore, urban soil is also essential for the sustainability and function of the urban habitat and ecological services, such as maintaining groundwater restraining urban floods etc. (Lehmann and Stahr 2007). There is no single set of rules to classify a functional urban green patch worth preserving. The aim of this study is to examine the effects of patch properties (including geometry, age, type and location along the urban gradient, connectivity, and urban matrix density) on the presence, abundance and characteristics of vegetation and soil conditions of remnant patches The inspired purpose is to eventually find an assessment for urban open green patches OGP quality by linking, patches attributes, plants indexes and soil quality indexes The research is conducted in the city of Haifa, which is located on the northern part of Mount Carmel in the north-western part of Israel . Mean annual rainfall, 550-800 mm, varies with latitude and the mean temperature is 18.80c. Modern Haifa is a relatively young city which maintains remnant vegetation patches within its municipal boundary. 32 OGP were selected in nine categories (size: small, medium and large, distance from city edge: far, average, near), in

  4. A comparative study of the effects of using normalized patches for penalized likelihood tomographic reconstruction

    NASA Astrophysics Data System (ADS)

    Ren, Xue; Lee, Soo-Jin

    2016-03-01

    Patch-based regularization methods, which have proven useful not only for image denoising, but also for tomographic reconstruction, penalize image roughness based on the intensity differences between two nearby patches. However, when two patches are not considered to be similar in the general sense of similarity but still have similar features in a scaled domain after normalizing the two patches, the difference between the two patches in the scaled domain is smaller than the intensity difference measured in the standard method. Standard patch-based methods tend to ignore such similarities due to the large intensity differences between the two patches. In this work, for patch-based penalized likelihood tomographic reconstruction, we propose a new approach to the similarity measure using the normalized patch differences as well as the intensity-based patch differences. A normalized patch difference is obtained by normalizing and scaling the intensity-based patch difference. To selectively take advantage of the standard patch (SP) and normalized patch (NP), we use switching schemes that can select either SP or NP based on the gradient of a reconstructed image. In this case the SP is selected for restoring large-scaled piecewise-smooth regions, while the NP is selected for preserving the contrast of fine details. The numerical experiments using software phantom demonstrate that our proposed methods not only improve overall reconstruction accuracy in terms of the percentage error, but also reveal better recovery of fine details in terms of the contrast recovery coefficient.

  5. Runoff and erosion in a pinon-juniper woodland: Influence of vegetation patches

    SciTech Connect

    Reid, K.D.; Wilcox, B.P.; Breshears, D.D.; MacDonald, L.

    1999-12-01

    In many semiarid regions, runoff and erosion differ according to vegetation patch type. These differences, although hypothesized to fundamentally affect ecological processes, have been poorly quantified. In a semiarid pinion-juniper woodland [Pinus edulis Engelm. and Juniperus monosperma (Engelm) Sarg.] in northern New Mexico, the authors measured runoff and erosion from the three patch types that compose these woodlands: Canopy patches (those beneath woody plants), vegetated patched in intercanopy areas, and bare patches in intercanopy areas. The bare intercanopy patches exhibited the highest rates, followed by vegetated intercanopy patches and then by canopy patches. Large convective summer storms, though relatively infrequent, generated much of the runoff and most of the sediment; prolonged frontal storms were capable of generating considerable runoff but little sediment. A portion of the runoff and most of the sediment generated from bare intercanopy patches was redistributed down-slope, probably to adjacent vegetated intercanopy patches, demonstrating connectivity between these two patch types. Their results indicate that there are significant and important differences in runoff and sediment production from the three patch types; that bare intercanopy patches act as sources of both water and sediment for the vegetated intercanopy patches; and that the transfer of water and sediment at small scales is both frequent enough and substantial enough to be considered ecologically significant.

  6. A Randomized Trial Comparing Part-time Patching with Observation for Intermittent Exotropia in Children 12 to 35 Months Old

    PubMed Central

    Mohney, Brian G.; Cotter, Susan A.; Chandler, Danielle L.; Holmes, Jonathan M.; Chen, Angela M.; Melia, Michele; Donahue, Sean P.; Wallace, David K.; Kraker, Raymond T.; Christian, Melanie L.; Suh, Donny W.

    2015-01-01

    Objective To determine the effectiveness of part-time patching for treating intermittent exotropia (IXT) in young children Design Multicenter, randomized clinical trial Participants Two hundred one children 12 to 35-months-old with untreated IXT meeting the following criteria: 1) IXT at distance OR constant exotropia at distance and either IXT or exophoria at near; 2) ≥15 prism diopter (Δ) exodeviation at distance or near by prism and alternate cover test (PACT) but at least 10Δ exodeviation at distance by PACT. Methods Participants were randomly assigned to either observation (no treatment for 6 months) or patching prescribed for 3 hours daily for 5 months, followed by 1 month of no patching. Main Outcome Measure The primary outcome was deterioration, defined as constant exotropia measuring at least 10Δ at distance and near or receipt of non-protocol treatment for IXT. Results Of the 177 participants (88%) completing the 6-month primary outcome examination, deterioration occurred in 4.6% (4 of 87) of the participants in the observation group and in 2.2% (2 of 90) of the participants in the patching group (difference = 2.4%; P = 0.27, 95% confidence interval (CI) = -3.8% to +9.4%). Motor deterioration occurred in 2.3% (2 of 87) of the observation group and in 2.2% (2 of 90) of the patching group (difference = 0.08%, P = 0.55, 95% CI = -5.8% to +6.1%). For the observation and patching groups respectively, 6-month mean PACT measurements were 27.9Δ versus 24.9Δ at distance (P = 0.02) and 19.3Δ versus 17.0Δ at near (P = 0.10); 6-month mean exotropia control scores were 2.8 vs. 2.3 points at distance (P = 0.02), and 1.4 vs. 1.1 points at near (P = 0.26). Conclusion Among children 12 to 35 months of age with previously untreated IXT, deterioration over 6 months was uncommon, with or without patching treatment. There was insufficient evidence to recommend part-time patching for the treatment of IXT in children in this age group. PMID:26072346

  7. Colour detection thresholds in faces and colour patches.

    PubMed

    Tan, Kok Wei; Stephen, Ian D

    2013-01-01

    Human facial skin colour reflects individuals' underlying health (Stephen et al 2011 Evolution & Human Behavior 32 216-227); and enhanced facial skin CIELab b* (yellowness), a* (redness), and L* (lightness) are perceived as healthy (also Stephen et al 2009a International Journal of Primatology 30 845-857). Here, we examine Malaysian Chinese participants' detection thresholds for CIELab L* (lightness), a* (redness), and b* (yellowness) colour changes in Asian, African, and Caucasian faces and skin coloured patches. Twelve face photos and three skin coloured patches were transformed to produce four pairs of images of each individual face and colour patch with different amounts of red, yellow, or lightness, from very subtle (deltaE = 1.2) to quite large differences (deltaE = 9.6). Participants were asked to decide which of sequentially displayed, paired same-face images or colour patches were lighter, redder, or yellower. Changes in facial redness, followed by changes in yellowness, were more easily discriminated than changes in luminance. However, visual sensitivity was not greater for redness and yellowness in nonface stimuli, suggesting red facial skin colour special salience. Participants were also significantly better at recognizing colour differences in own-race (Asian) and Caucasian faces than in African faces, suggesting the existence of cross-race effect in discriminating facial colours. Humans' colour vision may have been selected for skin colour signalling (Changizi et al 2006 Biology Letters 2 217-221), enabling individuals to perceive subtle changes in skin colour, reflecting health and emotional status.

  8. The pathways of Marine Plastic into the Ocean Garbage Patches

    NASA Astrophysics Data System (ADS)

    van Sebille, E.; England, M. H.; Froyland, G.

    2013-12-01

    Much of the plastic debris in the near-surface ocean collects in so-called garbage patches where, due to convergence of the surface flow, the debris is trapped for decades to millennia. Here, we use observational data from the Global Drifter Program in a particle-trajectory tracer approach to study the fate of marine debris in the open ocean from coastal regions around the world on interannual to centennial time scales. We find that garbage patches emerge in each of the five subtropical basins. The evolution of each of the five patches is markedly different, however. With the exception of the North Pacific, all patches are much more dispersive than expected from linear ocean circulation theory, suggesting that on centennial time scales the different basins are much better connected than previously thought and that inter-ocean exchanges play a large role in the spreading of marine debris. In order to increase public awareness on this issue of sustainability in the ocean, we have used the methods and data of this study to create a public website at www.adrift.org.au where all interested can investigate the spread of tracer from any and all points on the ocean surface.

  9. Use of microstrip patch antennas in grain permittivity measurement

    USGS Publications Warehouse

    El Sabbagh, M.A.; Ramahi, O.M.; Trabelsi, S.; Nelson, S.O.; Khan, L.

    2003-01-01

    In this paper, a compact size free-space setup is proposed for the measurement of complex permittivity of granular materials. The horn antennas in the conventional setup are replaced by microstrip patch antennas which is a step toward system miniaturization. The experimental results obtained are in good agreement with those obtained with horn antennas.

  10. A Flexible and Wearable Human Stress Monitoring Patch

    NASA Astrophysics Data System (ADS)

    Yoon, Sunghyun; Sim, Jai Kyoung; Cho, Young-Ho

    2016-03-01

    A human stress monitoring patch integrates three sensors of skin temperature, skin conductance, and pulsewave in the size of stamp (25 mm × 15 mm × 72 μm) in order to enhance wearing comfort with small skin contact area and high flexibility. The skin contact area is minimized through the invention of an integrated multi-layer structure and the associated microfabrication process; thus being reduced to 1/125 of that of the conventional single-layer multiple sensors. The patch flexibility is increased mainly by the development of flexible pulsewave sensor, made of a flexible piezoelectric membrane supported by a perforated polyimide membrane. In the human physiological range, the fabricated stress patch measures skin temperature with the sensitivity of 0.31 Ω/°C, skin conductance with the sensitivity of 0.28 μV/0.02 μS, and pulse wave with the response time of 70 msec. The skin-attachable stress patch, capable to detect multimodal bio-signals, shows potential for application to wearable emotion monitoring.

  11. Surgery for supravalvular aortic stenosis - the three-patch technique.

    PubMed

    Arnáiz, Elena; Koolbergen, Dave; Adsuar, Alejandro; Hazekamp, Mark G

    2008-01-01

    The objective of this paper is to describe the three-patch technique for repair of supravalvular aortic stenosis (SVAS). Supravalvular aortic stenosis is a rare malformation as a result of an abnormal thickening of the aortic wall. SVAS may present in two forms: a localized form (affecting only the aortic sinotubular junction) and a diffuse form, where the aortic arch and its side branches are also affected. Since 1960, multiple surgical techniques have been described with the aim of relieving the aortic narrowing and restoring the aortic root. We present the three-patch technique as originally developed by Brom. After transection of the aorta at the sinotubular junction, three longitudinal incisions are made into the three sinuses. The aortic root geometry is then restored by placement of three separate patches of autologous pericardium in the opened sinuses. Brom's technique provides a complete and symmetric restoration of the aortic anatomy. The technique is illustrated by angiographies, surgical drawings, videos and a review of the literature. The results of the three-patch technique are good and our long-term experience will be described.

  12. A Flexible and Wearable Human Stress Monitoring Patch.

    PubMed

    Yoon, Sunghyun; Sim, Jai Kyoung; Cho, Young-Ho

    2016-03-23

    A human stress monitoring patch integrates three sensors of skin temperature, skin conductance, and pulsewave in the size of stamp (25 mm × 15 mm × 72 μm) in order to enhance wearing comfort with small skin contact area and high flexibility. The skin contact area is minimized through the invention of an integrated multi-layer structure and the associated microfabrication process; thus being reduced to 1/125 of that of the conventional single-layer multiple sensors. The patch flexibility is increased mainly by the development of flexible pulsewave sensor, made of a flexible piezoelectric membrane supported by a perforated polyimide membrane. In the human physiological range, the fabricated stress patch measures skin temperature with the sensitivity of 0.31 Ω/°C, skin conductance with the sensitivity of 0.28 μV/0.02 μS, and pulse wave with the response time of 70 msec. The skin-attachable stress patch, capable to detect multimodal bio-signals, shows potential for application to wearable emotion monitoring.

  13. Dendritic Actin Nucleation Causes Traveling Waves and Patches

    NASA Astrophysics Data System (ADS)

    Carlsson, Anders

    2010-03-01

    Reversible polymerization of the intracellular protein actin into semiflexible filaments is crucial for cell motion and environmental sensing. Recent studies have shown that polymerized actin can spontaneously form traveling waves and/or moving patches. I investigate possible mechanisms for such phenomena by numerically simulating the ``dendritic nucleation'' model of actin network growth. The simulations treat the growth of an actin network on a flat portion of a cell membrane, using a stochastic-growth method which calculates an explicit three-dimensional network structure. The calculations treat processes including filament growth, capping, branching, severing, and Brownian motion. The dynamics of membrane proteins stimulating actin polymerization are also included: they diffuse in the membrane, and detach/deactivate in the presence of polymerized actin. The simulations show three types of polymerized-actin behavior: 1) traveling waves, 2) coherently moving patches, and 3) random fluctuations with occasional moving patches. Wave formation is favored at low free-actin concentrations by a long reattachment time for the membrane proteins, and by weakness of the attractive interaction between filaments and the membrane. Raising the free-actin concentration results in a randomly varying distribution of polymerized actin. Lowering the free-actin concentration below the optimal value for waves causes the waves to break up into patches which, however, move coherently. Effects of similar magnitude are predicted when other intracellular protein concentrations are varied. Diffusion of the membrane proteins slows the waves, and, if fast enough, stops them completely, resulting in the formation of a static spot.

  14. Optimum Three Impulse Trajectory Generator with Patched Conic Trajectory Model

    NASA Technical Reports Server (NTRS)

    Payne, M. H.; Pines, S.; Horsewood, J. L.

    1972-01-01

    Optimal multi-impulse trajectories were investigated as a nominal about which asymptotic expansion was used to obtain approximations of optimal low thrust trajectories. The work consisted of the analysis and description of an optimal 3-impulse trajectory program. A patched-conic trajectory model was specifically designed for compatibility with the subsequent addition of the low thrust expansion approximation.

  15. Dispersal, patch Leaving, and distribution of Homalodisca vitripennis (Hemiptera: Cicadellidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We identified the impact of plant diversity, and quality which were found to influence leafhopper tendencies to either disperse, or to remain, within a patch of plants. Understanding the underlying influences for leafhopper movement provides the information needed to create better management strateg...

  16. Development of a thermostable microneedle patch for influenza vaccination.

    PubMed

    Mistilis, Matthew J; Bommarius, Andreas S; Prausnitz, Mark R

    2015-02-01

    The goal of this study is to develop thermostable microneedle patch formulations for influenza vaccine that can be partially or completely removed from the cold chain. During vaccine drying associated with microneedle patch manufacturing, ammonium acetate and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer salts stabilized influenza vaccine, surfactants had little effect during drying, drying temperature had weak effects on vaccine stability, and drying on polydimethylsiloxane (PDMS) led to increased stability compared with drying on stainless steel. A number of excipients, mostly polysaccharides and some amino acids, further stabilized the influenza vaccine during drying. Over longer time scales of storage, combinations of stabilizers preserved the most vaccine activity. Finally, dissolving microneedle patches formulated with arginine and calcium heptagluconate had no significant activity loss for all three strains of seasonal influenza vaccine during storage at room temperature for 6 months. We conclude that appropriately formulated microneedle patches can exhibit remarkable thermostability that could enable storage and distribution of influenza vaccine outside the cold chain.

  17. Mechanical Behavior of Cracked Panels Repaired with Bonded Composite Patch

    DTIC Science & Technology

    2005-06-01

    inverse pyramid – smallest ply first. The layup is debulked after every 5 plies. 2. Typical patches for an actual repair have a layer of FM73 over the...in Normandy Park, Washington. He graduated fro Evergreen Lutheran Highschoo, Des Moines, Washington, in 1996. He then entered the University of

  18. A Flexible and Wearable Human Stress Monitoring Patch

    PubMed Central

    Yoon, Sunghyun; Sim, Jai Kyoung; Cho, Young-Ho

    2016-01-01

    A human stress monitoring patch integrates three sensors of skin temperature, skin conductance, and pulsewave in the size of stamp (25 mm × 15 mm × 72 μm) in order to enhance wearing comfort with small skin contact area and high flexibility. The skin contact area is minimized through the invention of an integrated multi-layer structure and the associated microfabrication process; thus being reduced to 1/125 of that of the conventional single-layer multiple sensors. The patch flexibility is increased mainly by the development of flexible pulsewave sensor, made of a flexible piezoelectric membrane supported by a perforated polyimide membrane. In the human physiological range, the fabricated stress patch measures skin temperature with the sensitivity of 0.31 Ω/°C, skin conductance with the sensitivity of 0.28 μV/0.02 μS, and pulse wave with the response time of 70 msec. The skin-attachable stress patch, capable to detect multimodal bio-signals, shows potential for application to wearable emotion monitoring. PMID:27004608

  19. Lung image patch classification with automatic feature learning.

    PubMed

    Li, Qing; Cai, Weidong; Feng, David Dagan

    2013-01-01

    Image patch classification is an important task in many different medical imaging applications. The classification performance is usually highly dependent on the effectiveness of image feature vectors. While many feature descriptors have been proposed over the past years, they can be quite complicated and domain-specific. Automatic feature learning from image data has thus emerged as a different trend recently, to capture the intrinsic image features without manual feature design. In this paper, we propose to create multi-scale feature extractors based on an unsupervised learning algorithm; and obtain the image feature vectors by convolving the feature extractors with the image patches. The auto-generated image features are data-adaptive and highly descriptive. A simple classification scheme is then used to classify the image patches. The proposed method is generic in nature and can be applied to different imaging domains. For evaluation, we perform image patch classification to differentiate various lung tissue patterns commonly seen in interstitial lung disease (ILD), and demonstrate promising results.

  20. Patch-scale connectivity: Where and why does it matter?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Patch-scale connectivity is frequently cited as a significant factor controlling redistribution of water, organic matter and nutrients in many arid and semi-arid ecosystems. The ‘leakiness’ of these systems has been cited as an indicator of degradation. Methods to limit or modify soil loss and redis...

  1. Astronomy Patch Day: An Interactive Astronomy Experience for Girl Scouts

    NASA Astrophysics Data System (ADS)

    Knierman, K. A.; McCarthy, D. W.; Schutz, K.

    2005-12-01

    To help encourage a new generation of women in science, we have created Astronomy Patch Day for the Sahuaro Girl Scout Council in Tucson, Arizona. This all-day event is an interactive experience for Girl Scouts ages 5-18 to learn about astronomical concepts and women in astronomy. Our first Astronomy Patch Day, held on March 19, 2005, in conjunction with the Sahuaro Council's annual Science, Math, and Related Technologies (SMART) program, was very successful, reaching about 150-200 girls and their leaders. Individual troops rotated every half hour among our six activity booths: Earth-Moon, Solar System, Stars, Galaxies, Universe, and Ask an Astronomer, which were staffed by trained Girl Scout Leaders as well as faculty, post-doctoral researchers, and graduate students from Steward Observatory. To earn a patch, younger girls (ages 5-12) had to complete activities at three booths and older girls had to complete all six activities. Positive feedback for this event was received from both the girls and leaders. We plan to hold Astronomy Patch Day annually, possibly with different and/or additional activities in future years. K. Knierman is supported by an Arizona/NASA Space Grant Fellowship. This outreach program is supported by NIRCam/JWST E/PO.

  2. Microneedle electrodes toward an amperometric glucose-sensing smart patch.

    PubMed

    Invernale, Michael A; Tang, Benjamin C; York, Royce L; Le, Long; Hou, David Yupeng; Anderson, Daniel G

    2014-03-01

    Here, efforts toward the development of a microneedle-based glucose sensor or "smart patch" for intradermal glucose sensing are described. Metallic microneedle array electrodes, conducting polymers, and glucose oxidase form the sensor platform. This work represents the first steps toward the development of painless, transdermal-sensing devices for continuous glucose monitoring.

  3. Speeding up 3D speckle tracking using PatchMatch

    NASA Astrophysics Data System (ADS)

    Zontak, Maria; O'Donnell, Matthew

    2016-03-01

    Echocardiography provides valuable information to diagnose heart dysfunction. A typical exam records several minutes of real-time cardiac images. To enable complete analysis of 3D cardiac strains, 4-D (3-D+t) echocardiography is used. This results in a huge dataset and requires effective automated analysis. Ultrasound speckle tracking is an effective method for tissue motion analysis. It involves correlation of a 3D kernel (block) around a voxel with kernels in later frames. The search region is usually confined to a local neighborhood, due to biomechanical and computational constraints. For high strains and moderate frame-rates, however, this search region will remain large, leading to a considerable computational burden. Moreover, speckle decorrelation (due to high strains) leads to errors in tracking. To solve this, spatial motion coherency between adjacent voxels should be imposed, e.g., by averaging their correlation functions.1 This requires storing correlation functions for neighboring voxels, thus increasing memory demands. In this work, we propose an efficient search using PatchMatch, 2 a powerful method to find correspondences between images. Here we adopt PatchMatch for 3D volumes and radio-frequency signals. As opposed to an exact search, PatchMatch performs random sampling of the search region and propagates successive matches among neighboring voxels. We show that: 1) Inherently smooth offset propagation in PatchMatch contributes to spatial motion coherence without any additional processing or memory demand. 2) For typical scenarios, PatchMatch is at least 20 times faster than the exact search, while maintaining comparable tracking accuracy.

  4. Computer modeling of endovascular patch welding using temperature feedback

    SciTech Connect

    Glinsky, M.E.; London, R.A.; Zimmerman, G.B.; Jacques, S.L.; Ols, J.D.

    1995-11-01

    A new computer program, LATIS, being developed at Lawrence Livermore National Laboratory is used to study the effect of pulsed laser irradiation with temperature feedback on endovascular patch welding. Various physical and biophysical effects are included in these simulations: laser light scattering and absorption, tissue heating and heat conduction, vascular cooling, and tissue thermal damage. The geometry of a patch being held against the inner vessel wall (500 {mu}m inner diameter) by a balloon is considered. The system is exposed to light pulsed from an optical fiber inside the balloon. The laser power is adjusted during the course of a pulse. This is done automatically in the simulation by temperature feedback. A minimum in the depth of damage into the vessel wall is found. The minimum damage zone is about the thickness of the patch material that is heated by the laser. The more ordered the tissue the thinner the minimum zone of damage. The pulse length which minimizes the zone of damage is found to be the time for energy to diffuse across the layer. The delay time between the pulses is determined by the time for the heated layer to cool down. An optimal pulse length exists which minimizes the total time needed to weld the patch to the wall while keeping the thickness of the damaged tissue to less than 100 {mu}m. For the case that is considered, a patch dyed with light absorbing ICG on the side next to the vessel (thickness of the dyed layer is 60 {mu}m), the best protocol is found to be 33-600 ms pulses applied over 1.6 min.

  5. Patch-based iterative conditional geostatistical simulation using graph cuts

    NASA Astrophysics Data System (ADS)

    Li, Xue; Mariethoz, Gregoire; Lu, DeTang; Linde, Niklas

    2016-08-01

    Training image-based geostatistical methods are increasingly popular in groundwater hydrology even if existing algorithms present limitations that often make real-world applications difficult. These limitations include a computational cost that can be prohibitive for high-resolution 3-D applications, the presence of visual artifacts in the model realizations, and a low variability between model realizations due to the limited pool of patterns available in a finite-size training image. In this paper, we address these issues by proposing an iterative patch-based algorithm which adapts a graph cuts methodology that is widely used in computer graphics. Our adapted graph cuts method optimally cuts patches of pixel values borrowed from the training image and assembles them successively, each time accounting for the information of previously stitched patches. The initial simulation result might display artifacts, which are identified as regions of high cost. These artifacts are reduced by iteratively placing new patches in high-cost regions. In contrast to most patch-based algorithms, the proposed scheme can also efficiently address point conditioning. An advantage of the method is that the cut process results in the creation of new patterns that are not present in the training image, thereby increasing pattern variability. To quantify this effect, a new measure of variability is developed, the merging index, quantifies the pattern variability in the realizations with respect to the training image. A series of sensitivity analyses demonstrates the stability of the proposed graph cuts approach, which produces satisfying simulations for a wide range of parameters values. Applications to 2-D and 3-D cases are compared to state-of-the-art multiple-point methods. The results show that the proposed approach obtains significant speedups and increases variability between realizations. Connectivity functions applied to 2-D models transport simulations in 3-D models are used to

  6. Do geese fully develop brood patches? A histological analysis of lesser snow geese (Chen caerulescens caerulescens) and Ross's geese (C. rossii)

    USGS Publications Warehouse

    Jonsson, J.E.; Afton, A.D.; Homberger, D.G.; Henk, W.G.; Alisauskas, R.T.

    2006-01-01

    Most birds develop brood patches before incubation; epidermis and dermis in the brood patch region thicken, and the dermal connective tissue becomes increasingly vascularized and infiltrated by leukocytes. However, current dogma states that waterfowl incubate without modifications of skin within the brood patch region. The incubation periods of lesser snow geese (Chen caerulescens caerulescens; hereafter called snow geese) and Ross's geese (C. rossii) are 2-6 days shorter than those of other goose species; only females incubate. Thus, we hypothesized that such short incubation periods would require fully developed brood patches for sufficient heat transfer from incubating parents to eggs. We tested this hypothesis by analyzing the skin histology of abdominal regions of snow and Ross's geese collected at Karrak Lake, Nunavut, Canada. For female snow geese, we found that epidermis and dermis had thickened and vascularization of dermis was 14 times greater, on average, than that observed in males (n=5 pairs). Our results for Ross's geese (n=5 pairs) were more variable, wherein only one of five female Ross's geese fully developed a brood patch. Our results are consistent with three hypotheses about brood patch development and its relationship with different energetic cost-benefit relationships, resulting from differences in embryonic development and body size. ?? Springer-Verlag 2006.

  7. Do geese fully develop brood patches? A histological analysis of lesser snow geese (Chen caerulescens caerulescens) and Ross's geese (C. rossii).

    PubMed

    Jónsson, Jón Einar; Afton, Alan D; Homberger, Dominique G; Henk, William G; Alisauskas, Ray T

    2006-06-01

    Most birds develop brood patches before incubation; epidermis and dermis in the brood patch region thicken, and the dermal connective tissue becomes increasingly vascularized and infiltrated by leukocytes. However, current dogma states that waterfowl incubate without modifications of skin within the brood patch region. The incubation periods of lesser snow geese (Chen caerulescens caerulescens; hereafter called snow geese) and Ross's geese (C. rossii) are 2-6 days shorter than those of other goose species; only females incubate. Thus, we hypothesized that such short incubation periods would require fully developed brood patches for sufficient heat transfer from incubating parents to eggs. We tested this hypothesis by analyzing the skin histology of abdominal regions of snow and Ross's geese collected at Karrak Lake, Nunavut, Canada. For female snow geese, we found that epidermis and dermis had thickened and vascularization of dermis was 14 times greater, on average, than that observed in males (n=5 pairs). Our results for Ross's geese (n=5 pairs) were more variable, wherein only one of five female Ross's geese fully developed a brood patch. Our results are consistent with three hypotheses about brood patch development and its relationship with different energetic cost-benefit relationships, resulting from differences in embryonic development and body size.

  8. Effects of patch quality and network structure on patch occupancy dynamics of a yellow-bellied marmot metapopulation.

    PubMed

    Ozgul, Arpat; Armitage, Kenneth B; Blumstein, Daniel T; Vanvuren, Dirk H; Oli, Madan K

    2006-01-01

    1. The presence/absence of a species at a particular site is the simplest form of data that can be collected during ecological field studies. We used 13 years (1990-2002) of survey data to parameterize a stochastic patch occupancy model for a metapopulation of the yellow-bellied marmot in Colorado, and investigated the significance of particular patches and the influence of site quality, network characteristics and regional stochasticity on the metapopulation persistence. 2. Persistence of the yellow-bellied marmot metapopulation was strongly dependent on the high quality colony sites, and persistence probability was highly sensitive to small changes in the quality of these sites. 3. A relatively small number of colony sites was ultimately responsible for the regional persistence. However, lower quality satellite sites also made a significant contribution to long-term metapopulation persistence, especially when regional stochasticity was high. 4. The northern network of the marmot metapopulation was more stable compared to the southern network, and the persistence of the southern network depended heavily on the northern network. 5. Although complex models of metapopulation dynamics may provide a more accurate description of metapopulation dynamics, such models are data-intensive. Our study, one of the very few applications of stochastic patch occupancy models to a mammalian species, suggests that stochastic patch occupancy models can provide important insights into metapopulation dynamics using data that are easy to collect.

  9. Grassland fire and cattle grazing regulate reptile and amphibian assembly among patches.

    PubMed

    Larson, Danelle M

    2014-12-01

    Fire and grazing are common management schemes of grasslands globally and are potential drivers of reptilian and amphibian (herpetofauna) metacommunity dynamics. Few studies have assessed the impacts of fire and cattle grazing on herpetofauna assemblages in grasslands. A patch-burn grazing study at Osage Prairie, MO, USA in 2011-2012 created landscape patches with treatments of grazing, fire, and such legacies. Response variables were measured before and after the application of treatments, and I used robust-design occupancy modeling to estimate patch occupancy and detection rate within patches, and recolonization and extinction (i.e., dispersal) across patches. I conducted redundancy analysis and a permuted multivariate analysis of variance to determine if patch type and the associated environmental factors explained herpetofauna assemblage. Estimates for reptiles indicate that occupancy was seasonally constant in Control patches (ψ ~ 0.5), but declined to ψ ~ 0.15 in patches following the applications of fire and grazing. Local extinctions for reptiles were higher in patches with fire or light grazing (ε ~ 0.7) compared to the controls. For the riparian herpetofaunal community, patch type and grass height were important predictors of abundance; further, the turtles, lizards, snakes, and adult amphibians used different patch types. The aquatic amphibian community was predicted by watershed and in-stream characteristics, irrespective of fire or grazing. The varying responses from taxonomic groups demonstrate habitat partitioning across multiple patch types undergoing fire, cattle grazing, and legacy effects. Prairies will need an array of patch types to accommodate multiple herpetofauna species.

  10. Grassland Fire and Cattle Grazing Regulate Reptile and Amphibian Assembly Among Patches

    NASA Astrophysics Data System (ADS)

    Larson, Danelle M.

    2014-12-01

    Fire and grazing are common management schemes of grasslands globally and are potential drivers of reptilian and amphibian (herpetofauna) metacommunity dynamics. Few studies have assessed the impacts of fire and cattle grazing on herpetofauna assemblages in grasslands. A patch-burn grazing study at Osage Prairie, MO, USA in 2011-2012 created landscape patches with treatments of grazing, fire, and such legacies. Response variables were measured before and after the application of treatments, and I used robust-design occupancy modeling to estimate patch occupancy and detection rate within patches, and recolonization and extinction (i.e., dispersal) across patches. I conducted redundancy analysis and a permuted multivariate analysis of variance to determine if patch type and the associated environmental factors explained herpetofauna assemblage. Estimates for reptiles indicate that occupancy was seasonally constant in Control patches ( ψ ~ 0.5), but declined to ψ ~ 0.15 in patches following the applications of fire and grazing. Local extinctions for reptiles were higher in patches with fire or light grazing ( ɛ ~ 0.7) compared to the controls. For the riparian herpetofaunal community, patch type and grass height were important predictors of abundance; further, the turtles, lizards, snakes, and adult amphibians used different patch types. The aquatic amphibian community was predicted by watershed and in-stream characteristics, irrespective of fire or grazing. The varying responses from taxonomic groups demonstrate habitat partitioning across multiple patch types undergoing fire, cattle grazing, and legacy effects. Prairies will need an array of patch types to accommodate multiple herpetofauna species.

  11. Single-unit recordings in the macaque face patch system reveal limitations of fMRI MVPA.

    PubMed

    Dubois, Julien; de Berker, Archy Otto; Tsao, Doris Ying

    2015-02-11

    Multivariate pattern analysis (MVPA) of fMRI data has become an important technique for cognitive neuroscientists in recent years; however, the relationship between fMRI MVPA and the underlying neural population activity remains unexamined. Here, we performed MVPA of fMRI data and single-unit data in the same species, the macaque monkey. Facial recognition in the macaque is subserved by a well characterized system of cortical patches, which provided the test bed for our comparison. We showed that neural population information about face viewpoint was readily accessible with fMRI MVPA from all face patches, in agreement with single-unit data. Information about face identity, although it was very strongly represented in the populations of units of the anterior face patches, could not be retrieved from the same data. The discrepancy was especially striking in patch AL, where neurons encode both the identity and viewpoint of human faces. From an analysis of the characteristics of the neural representations for viewpoint and identity, we conclude that fMRI MVPA cannot decode information contained in the weakly clustered neuronal responses responsible for coding the identity of human faces in the macaque brain. Although further studies are needed to elucidate the relationship between information decodable from fMRI multivoxel patterns versus single-unit populations for other variables in other brain regions, our result has important implications for the interpretation of negative findings in fMRI multivoxel pattern analyses.

  12. Changes in diatom patch-size distribution and degradation in a spatially self-organized intertidal mudflat ecosystem.

    PubMed

    Weerman, E J; Van Belzen, J; Rietkerk, M; Temmerman, S; Kéfi, S; Herman, P M J; Van de Koppel, J

    2012-03-01

    Self-organized spatial patterns have been proposed as possible indicators for regime shifts in ecosystems. Until now, this hypothesis has only been tested in drylands. Here, we focus on intertidal mudflats where regular spatial patterns develop in early spring from the interaction between diatom growth and sedimentation but disappear when benthic herbivore abundance increases in early summer, accompanied by a dramatic shift to a bare mudflat. We followed the patch-size distributions of diatom biofilms during this degradation process. As time progressed, we found a temporal change in the spatial configuration occurring simultaneously with the loss of the diatom-sediment feedback. This indicates a gradual failure in time of the self-organization process that underlies regular patterning in this ecosystem. The path to degradation co-occurred with the loss of the larger patches in the ecosystem, which resulted in a decrease of the truncation in the patch-size distribution. Hence, our study in mudflat ecosystems confirms the general hypothesis that spatial patterns can provide important clues about the level of degradation. Nevertheless, our study highlights the need for thorough study about the type of spatial patterns and the nature of the underlying feedbacks before a reliable assessment of ecosystem status can be made, as changes in patch-size distribution differed markedly with those observed in other ecosystems.

  13. Initial characterization of a gel patch dosimeter for in vivo dosimetry

    NASA Astrophysics Data System (ADS)

    Matrosic, C.; Culberson, W.; Rosen, B.; Madsen, E.; Frank, G.; Bednarz, B.

    2016-05-01

    In vivo dosimetry is a greatly underutilized tool for patient safety in clinical external beam radiotherapy treatments, despite being recommended by several national and international organizations (AAPM, ICRU, IAEA, NACP). The reasons for this underutilization mostly relate to the feasibility and cost of in vivo dosimetry methods. Due to the increase in the number of beam angles and dose per fraction in modern treatments, there is a compelling need for a novel dosimeter that is robust and affordable while able to operate properly in these complex conditions. This work presents a gel patch dosimeter as a novel method of in vivo dosimetry. DEFGEL, a 6% T normoxic polyacrylamide gel, was injected into 1 cm thick acrylic molds to create 1 cm thick small cylindrical patch dosimeters. To evaluate the change in optical density due to radiation induced polymerization, dosimeters were scanned before and after irradiation using an in-house developed laser densitometer. The dose-responses of three separate batches of gel were evaluated and compared to check for linearity and repeatability. The response development time was evaluated to ensure that the patch dosimeter could be high throughput. Additionally, the potential of this system to be used as an in vivo dosimeter was tested with a clinically relevant end-to-end in vivo phantom test. All irradiations were performed with a Varian Clinac 21EX at the University of Wisconsin Medical Radiation Research Center (UWMRRC). The dose-response of all three batches of gel was found to be linear within the range of 2-20 Gy. At doses below 0.5 Gy the statistical uncertainties were prohibitively large to make quantitative assessments of the results. The three batches demonstrated good repeatability in the range of 2 Gy to up to 10 Gy, with only slight variations in response at higher doses. For low doses the dosimeter fully developed within an hour while at higher doses they fully developed within four hours. During the in vivo

  14. Left ventricle remodelling by double-patch sandwich technique

    PubMed Central

    Tappainer, Ernesto; Fiorani, Vinicio; Pederzolli, Nicola; Manfredi, Jacopo; Nocchi, Andrea; Zogno, Mario

    2007-01-01

    Background The sandwich double-patch technique was adopted as an alternative method for reconstruction of the left ventricle after excision of postinfarction dysfunctional myocardium to solve technical problems due to the thick edges of the ventricular wall. Methods Over a 5-year period, 12 of 21 patients with postinfarction antero-apical left ventricular aneurysm had thick wall edges after wall excision. It was due to akinetic muscular thick tissue in 6 cases, while in the other 6 with classic fibrous aneurysm, thick edges remained after the cut of the border zone. The ventricular opening was sandwiched between two patches and this is a technique which is currently used for the treatment of the interventricular septum rupture. In our patients the patches are much smaller than the removed aneurysm and they were sutured simply by a single row of single stitches. However, in contrast to interventricular septum rupture where the patches loosen the tension of the tissues, in our patients the patches pull strongly and restrain the walls by fastening their edges and supporting tight stitches. In this way they could narrow the cavity and close the ventricle. Results The resected area varied from 5 × 4 to 8 × 8 cm. Excision was extended into the interventricular septum in 5 patients, thus opening the right ventricle. CABG was performed on all patients but two. Left ventricular volumes and the ejection fraction changed significantly: end-systolic volume 93.5 ± 12.4 to 57.8 ± 8.9 ml, p < 0.001; end-diastolic volume 157.2 ± 16.7 to 115.3 ± 14.9 ml, p < 0.001; ejection fraction 40.3 ± 4.2 to 49.5 ± 5.7%, p < 0.001. All patients did well. One patient suffered from bleeding, which was not from the wall suture, and another had a left arm paresis. The post-operative hospital stay was 5 to 30 days with a mean 10.5 ± 7.5 days/patient. At follow-up, 9 to 60 months mean 34, all patients were symptom-free. NYHA class 2.5 ± 0.8 changed to 1.2 ± 0.4, p < 0.001. Conclusion The

  15. Intelligent Patching of Conceptual Geometry for CFD Analysis

    NASA Technical Reports Server (NTRS)

    Li, Wu

    2010-01-01

    The iPatch computer code for intelligently patching surface grids was developed to convert conceptual geometry to computational fluid dynamics (CFD) geometry (see figure). It automatically uses bicubic B-splines to extrapolate (if necessary) each surface in a conceptual geometry so that all the independently defined geometric components (such as wing and fuselage) can be intersected to form a watertight CFD geometry. The software also computes the intersection curves of surface patches at any resolution (up to 10.4 accuracy) specified by the user, and it writes the B-spline surface patches, and the corresponding boundary points, for the watertight CFD geometry in the format that can be directly used by the grid generation tool VGRID. iPatch requires that input geometry be in PLOT3D format where each component surface is defined by a rectangular grid {(x(i,j), y(i,j), z(i,j)):1less than or equal to i less than or equal to m, 1 less than or equal to j less than or equal to n} that represents a smooth B-spline surface. All surfaces in the PLOT3D file conceptually represent a watertight geometry of components of an aircraft on the half-space y greater than or equal to 0. Overlapping surfaces are not allowed, but could be fixed by a utility code "fixp3d". The fixp3d utility code first finds the two grid lines on the two surface grids that are closest to each other in Hausdorff distance (a metric to measure the discrepancies of two sets); then uses one of the grid lines as the transition line, extending grid lines on one grid to the other grid to form a merged grid. Any two connecting surfaces shall have a "visually" common boundary curve, or can be described by an intersection relationship defined in a geometry specification file. The intersection of two surfaces can be at a conceptual level. However, the intersection is directional (along either i or j index direction), and each intersecting grid line (or its spine extrapolation) on the first surface should intersect

  16. Rapid Establishment of a Regular Distribution of Adult Tropical Drosophila Parasitoids in a Multi-Patch Environment by Patch Defence Behaviour

    PubMed Central

    de Jong, Peter W.; Hemerik, Lia; Gort, Gerrit; van Alphen, Jacques J. M.

    2011-01-01

    Females of the larval parasitoid of Drosophila, Asobara citri, from sub-Saharan Africa, defend patches with hosts by fighting and chasing conspecific females upon encounter. Females of the closely related, palearctic species Asobara tabida do not defend patches and often search simultaneously in the same patch. The effect of patch defence by A. citri females on their distribution in a multi-patch environment was investigated, and their distributions were compared with those of A. tabida. For both species 20 females were released from two release-points in replicate experiments. Females of A. citri quickly reached a regular distribution across 16 patches, with a small variance/mean ratio per patch. Conversely, A. tabida females initially showed a clumped distribution, and after gradual dispersion, a more Poisson-like distribution across patches resulted (variance/mean ratio was closer to 1 and higher than for A. citri). The dispersion of A. tabida was most probably an effect of exploitation: these parasitoids increasingly made shorter visits to already exploited patches. We briefly discuss hypotheses on the adaptive significance of patch defence behaviour or its absence in the light of differences in the natural history of both parasitoid species, notably the spatial distribution of their hosts. PMID:21765889

  17. A Patch to MCNP5 for Multiplication Inference: Description and User Guide

    SciTech Connect

    Solomon, Jr., Clell J.

    2014-05-05

    A patch to MCNP5 has been written to allow generation of multiple neutrons from a spontaneous-fission event and generate list-mode output. This report documents the implementation and usage of this patch.

  18. Exploratory Study of MM-wave Patch Antennas for Strain Measurement and Crack Detection

    DTIC Science & Technology

    2008-08-31

    b) microstrip line feeding. 5 4. Antenna fabrication The patch antennas were fabricated on a flexible polyimide film (Kapton HN) using...the patch antenna was designed to be fed using a microstrip line, as shown in Figure 2.b. The microstrip line joins the metallic patch at (0, y0...which means only the impedance of the patch antenna for the TM01 mode is matched. The length and the width of the microstrip line were tuned to achieve

  19. A Nonadjuvanted Transcutaneous Tetanus Patch Is Effective in Boosting Anti-Tetanus Toxoid Immune Responses

    PubMed Central

    Seid, Robert C.; Reinisch, Christoph; Schlegl, Robert; Moehlen, Michael; Meinke, Andreas

    2014-01-01

    Dry tetanus toxoid (TTx) patches were formulated without any adjuvant, with excipients to impart antigen stabilization and to enhance skin delivery. The booster effects of the TTx patches were assessed using a guinea pig model. The study revealed significant rises in TTx IgG titers induced by the TTx patches after a low-dose subcutaneous (s.c.) prime with TTx adsorbed to aluminum hydroxide. The TTx patch can therefore be considered an effective alternative to a subcutaneous booster. PMID:24334688

  20. A nonadjuvanted transcutaneous tetanus patch is effective in boosting anti-tetanus toxoid immune responses.

    PubMed

    Seid, Robert C; Reinisch, Christoph; Schlegl, Robert; Moehlen, Michael; Meinke, Andreas; Lundberg, Urban

    2014-02-01

    Dry tetanus toxoid (TTx) patches were formulated without any adjuvant, with excipients to impart antigen stabilization and to enhance skin delivery. The booster effects of the TTx patches were assessed using a guinea pig model. The study revealed significant rises in TTx IgG titers induced by the TTx patches after a low-dose subcutaneous (s.c.) prime with TTx adsorbed to aluminum hydroxide. The TTx patch can therefore be considered an effective alternative to a subcutaneous booster.

  1. Studying a disease with no home - lessons in trial recruitment from the PATCH II study

    PubMed Central

    2010-01-01

    Background Cellulitis is a very common condition that often recurs. The PATCH II study was designed to explore the possibility of preventing future episodes of cellulitis, with resultant cost savings for the NHS. This was the first trial to be undertaken by the UK Dermatology Clinical Trials Network. As such, it was the first to test a recruitment model that involved many busy clinicians each contributing just a few patients. Methods A double-blind randomised controlled trial comparing prophylactic antibiotics (penicillin V) with placebo tablets, for the prevention of repeat episodes of cellulitis of the leg. Primary outcome was time to subsequent recurrence of cellulitis. Results The PATCH II study was closed to recruitment having enrolled 123 participants from a target of 400. Whilst the recruitment period was extended by 12 months, it was not possible to continue beyond this point without additional funds. Many factors contributed to poor recruitment: (i) changes in hospital policy and the introduction of community-based intravenous teams resulted in fewer cellulitis patients being admitted to hospital; ii) those who were admitted were seen by many different specialties, making it difficult for a network of dermatology clinicians to identify suitable participants; and iii) funding for research staff was limited to a trial manager and a trial administrator at the co-ordinating centre. With no dedicated research nurses at the recruiting centres, it was extremely difficult to maintain momentum and interest in the study. Attempts to boost recruitment by providing some financial support for principal investigators to employ local research staff was of limited success. Discussion The model of a network of busy NHS clinicians all recruiting a few patients into large clinical studies requires further testing. It did not work very well for PATCH II, but this was probably because patients were not routinely seen by dermatologists, and recruitment took place prior to

  2. Lung nodule classification with multilevel patch-based context analysis.

    PubMed

    Zhang, Fan; Song, Yang; Cai, Weidong; Lee, Min-Zhao; Zhou, Yun; Huang, Heng; Shan, Shimin; Fulham, Michael J; Feng, Dagan D

    2014-04-01

    In this paper, we propose a novel classification method for the four types of lung nodules, i.e., well-circumscribed, vascularized, juxta-pleural, and pleural-tail, in low dose computed tomography scans. The proposed method is based on contextual analysis by combining the lung nodule and surrounding anatomical structures, and has three main stages: an adaptive patch-based division is used to construct concentric multilevel partition; then, a new feature set is designed to incorporate intensity, texture, and gradient information for image patch feature description, and then a contextual latent semantic analysis-based classifier is designed to calculate the probabilistic estimations for the relevant images. Our proposed method was evaluated on a publicly available dataset and clearly demonstrated promising classification performance.

  3. Microelectromechanical Systems (MEMS) Actuator for Reconfigurable Patch Antenna Demonstrated

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.

    2001-01-01

    A microstrip patch antenna with two contact actuators along the radiating edges for frequency reconfiguration was demonstrated at K-band frequencies. The layout of the antenna is shown in the following figure. This antenna has the following advantages over conventional semiconductor varactor-diode-tuned patch antennas: 1. By eliminating the semiconductor diode and its nonlinear I-V characteristics, the antenna minimizes intermodulation signal distortion. This is particularly important in digital wireless systems, which are sensitive to intersymbol interference caused by intermodulation products. 2. Because the MEMS actuator is an electrostatic device, it does not draw any current during operation and, hence, requires a negligible amount of power for actuation. This is an important advantage for hand-held, battery-operated, portable wireless systems since the battery does not need to be charged frequently. 3. The MEMS actuator does not require any special epitaxial layers as in the case of diodes and, hence, is cost effective.

  4. Comparison of shrinkage related properties of various patch repair materials

    NASA Astrophysics Data System (ADS)

    Kristiawan, S. A.; Fitrianto, R. S.

    2017-02-01

    A patch repair material has been developed in the form of unsaturated polyester resin (UPR)-mortar. The performance and durability of this material are governed by its compatibility with the concrete being repaired. One of the compatibility issue that should be tackled is the dimensional compatibility as a result of differential shrinkage between the repair material and the concrete substrate. This research aims to evaluate such shrinkage related properties of UPR-mortar and to compare with those of other patch repair materials. The investigation includes the following aspects: free shrinkage, resistance to delamination and cracking. The results indicate that UPR-mortar poses a lower free shrinkage, lower risk of both delamination and cracking tendency in comparison to other repair materials.

  5. Ion transport through macrocapillaries - Oscillations due to charge patch formation

    NASA Astrophysics Data System (ADS)

    Kulkarni, D. D.; Lyle, L. A. M.; Sosolik, C. E.

    2016-09-01

    We present results on ion transport through large bore capillaries (macrocapillaries) that probe both the geometric and ion-guided aspects of this ion delivery mechanism. We have demonstrated that guiding in macrocapillaries exhibits position- and angle-dependent transmission properties which are directly related to the capillary material (either metal or insulator) and geometry. Specifically, we have passed 1 keV Rb+ ions through glass and metal macrocapillaries, and have observed oscillations for the transmitted ion current passing through the insulating capillaries. Straightforward calculations show that these oscillations can be attributed to beam deflections from charge patches that form on the interior walls of the capillary. The absence of these oscillations in the metal capillary data serve as further confirmation of the role of charge patch formation.

  6. Transbuccal delivery of chlorpheniramine maleate from mucoadhesive buccal patches.

    PubMed

    Sekhar, K Chandra; Naidu, K V S; Vishnu, Y Vamshi; Gannu, Ramesh; Kishan, V; Rao, Y Madhusudan

    2008-01-01

    This article describes buccal permeation of chlorpheniramine maleate (CPM) and its transbuccal delivery using mucoadhesive buccal patches. Permeation of CPM was calculated in vitro using porcine buccal membrane and in vivo in healthy humans. Buccal formulations were developed with hydroxyethylcellulose (HEC) and evaluated for in vitro release, moisture absorption, mechanical properties, and bioadhesion, and optimized formulation was subjected for bioavailability studies in healthy human volunteers. In vitro flux of CPM was calculated to be 0.14 +/- 0.03 mg.h(-1).cm(-2) and buccal absorption also was demonstrated in vivo in human volunteers. In vitro drug release and moisture absorbed were governed by HEC content and formulations exhibited good tensile and mucoadhesive properties. Bioavailability from optimized buccal patch was 1.46 times higher than the oral dosage form and the results showed statistically significant difference.

  7. Comparative study of icy patches on comet nuclei

    NASA Astrophysics Data System (ADS)

    Oklay, Nilda; Pommerol, Antoine; Barucci, Maria Antonietta; Sunshine, Jessica; Sierks, Holger; Pajola, Maurizio

    2016-07-01

    Cometary missions Deep Impact, EPOXI and Rosetta investigated the nuclei of comets 9P/Tempel 1, 103P/Hartley 2 and 67P/Churyumov-Gerasimenko respectively. Bright patches were observed on the surfaces of each of these three comets [1-5]. Of these, the surface of 67P is mapped at the highest spatial resolution via narrow angle camera (NAC) of the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS, [6]) on board the Rosetta spacecraft. OSIRIS NAC is equipped with twelve filters covering the wavelength range of 250 nm to 1000 nm. Various filters combinations are used during surface mapping. With high spatial resolution data of comet 67P, three types of bright features were detected on the comet surface: Clustered, isolated and bright boulders [2]. In the visible spectral range, clustered bright features on comet 67P display bluer spectral slopes than the average surface [2, 4] while isolated bright features on comet 67P have flat spectra [4]. Icy patches observed on the surface of comets 9P and 103P display bluer spectral slopes than the average surface [1, 5]. Clustered and isolated bright features are blue in the RGB composites generated by using the images taken in NIR, visible and NUV wavelengths [2, 4]. This is valid for the icy patches observed on comets 9P and 103P [1, 5]. Spectroscopic observations of bright patches on comets 9P and 103P confirmed the existence of water [1, 5]. There were more than a hundred of bright features detected on the northern hemisphere of comet 67P [2]. Analysis of those features from both multispectral data and spectroscopic data is an ongoing work. Water ice is detected in eight of the bright features so far [7]. Additionally, spectroscopic observations of two clustered bright features on the surface of comet 67P revealed the existence of water ice [3]. The spectral properties of one of the icy patches were studied by [4] using OSIRIS NAC images and compared with the spectral properties of the active regions observed

  8. Localized Patch-Based Fuzzy Active Contours for Image Segmentation

    PubMed Central

    Liu, Huaxiang; Zhang, Liting; Liu, Jun

    2016-01-01

    This paper presents a novel fuzzy region-based active contour model for image segmentation. By incorporating local patch-energy functional along each pixel of the evolving curve into the fuzziness of the energy, we construct a patch-based energy function without the regurgitation term. Its purpose is not only to make the active contour evolve very stably without the periodical initialization during the evolution but also to reduce the effect of noise. In particular, in order to reject local minimal of the energy functional, we utilize a direct method to calculate the energy alterations instead of solving the Euler-Lagrange equation of the underlying problem. Compared with other fuzzy active contour models, experimental results on synthetic and real images show the advantages of the proposed method in terms of computational efficiency and accuracy. PMID:28070210

  9. An extended patch-dynamic framework for food chains in fragmented landscapes

    PubMed Central

    Liao, Jinbao; Chen, Jiehong; Ying, Zhixia; Hiebeler, David E.; Nijs, Ivan

    2016-01-01

    Habitat destruction, a key determinant of species loss, can be characterized by two components, patch loss and patch fragmentation, where the former refers to the reduction in patch availability, and the latter to the division of the remaining patches. Classical metacommunity models have recently explored how food web dynamics respond to patch loss, but the effects of patch fragmentation have largely been overlooked. Here we develop an extended patch-dynamic model that tracks the patch occupancy of the various trophic links subject to colonization-extinction-predation dynamics by incorporating species dispersal with patch connectivity. We found that, in a simple food chain, species at higher trophic level become extinct sooner with increasing patch loss and fragmentation due to the constraint in resource availability, confirming the trophic rank hypothesis. Yet, effects of fragmentation on species occupancy are largely determined by patch loss, with maximal fragmentation effects occurring at intermediate patch loss. Compared to the spatially explicit simulations that we also performed, the current model with pair approximation generates similar community patterns especially in spatially clustered landscapes. Overall, our extended framework can be applied to model more complex food webs in fragmented landscapes, broadening the scope of existing metacommunity theory. PMID:27608823

  10. Patch occupancy and dispersal of spruce grouse on the edge of its range in Maine

    USGS Publications Warehouse

    Whitcomb, S.A.; Servello, F.A.; O'Connell, A.F.

    1996-01-01

    We surveyed 18 habitat patches (black spruce (Picea marinana) - tamarack (Larix larcina) wetlands) for spruce grouse (Dendragapus canadensis canadensis) on Mount Desert Island, Maine, during April-May in 1992 and 1993 to determine patch occupancy relative to patch area. We also equipped nine juvenile grouse with radio transmitters to determine movement and habitat use outside of patches during autumn dispersal. The 2 large patches (77 and 269 ha), 5 of 6 medium-sized (11-26 ha) patches, and 1 of 10 small (4-8 ha) patches were occupied. Spruce grouse occupied smaller habitat patches than previously reported, and occupied patches were closer (P < 0.05) to the nearest occupied patch (x = 1.2 km) than were unoccupied patches (x = 2.5 km). Eight of nine juvenile grouse left their natal habitat patch during autumn dispersal, and net dispersal distance (x = 2.3 km) was greater than that reported for grouse in areas with more contiguous habitat. Dispersing juveniles used all major forest types and 33 % of relocations were in deciduous forest. Thus, deciduous forest was not an absolute dispersal barrier.

  11. 21 CFR 310.103 - New drug substances intended for hypersensitivity testing.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... distributor by a practitioner licensed by law to administer such drugs, and the use of such drugs for patch... other labeling provisions of the act: (i) “Rx only”; and (ii) “For use only in patch testing”. (4) The quantity shipped is limited to an amount reasonable for the purpose of patch testing in the normal...

  12. 21 CFR 310.103 - New drug substances intended for hypersensitivity testing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... distributor by a practitioner licensed by law to administer such drugs, and the use of such drugs for patch... other labeling provisions of the act: (i) “Rx only”; and (ii) “For use only in patch testing”. (4) The quantity shipped is limited to an amount reasonable for the purpose of patch testing in the normal...

  13. Conservative Patch Algorithm and Mesh Sequencing for PAB3D

    NASA Technical Reports Server (NTRS)

    Pao, S. P.; Abdol-Hamid, K. S.

    2005-01-01

    A mesh-sequencing algorithm and a conservative patched-grid-interface algorithm (hereafter Patch Algorithm ) have been incorporated into the PAB3D code, which is a computer program that solves the Navier-Stokes equations for the simulation of subsonic, transonic, or supersonic flows surrounding an aircraft or other complex aerodynamic shapes. These algorithms are efficient, flexible, and have added tremendously to the capabilities of PAB3D. The mesh-sequencing algorithm makes it possible to perform preliminary computations using only a fraction of the grid cells (provided the original cell count is divisible by an integer) along any grid coordinate axis, independently of the other axes. The patch algorithm addresses another critical need in multi-block grid situation where the cell faces of adjacent grid blocks may not coincide, leading to errors in calculating fluxes of conserved physical quantities across interfaces between the blocks. The patch algorithm, based on the Stokes integral formulation of the applicable conservation laws, effectively matches each of the interfacial cells on one side of the block interface to the corresponding fractional cell area pieces on the other side. This approach is comprehensive and unified such that all interface topology is automatically processed without user intervention. This algorithm is implemented in a preprocessing code that creates a cell-by-cell database that will maintain flux conservation at any level of full or reduced grid density as the user may choose by way of the mesh-sequencing algorithm. These two algorithms have enhanced the numerical accuracy of the code, reduced the time and effort for grid preprocessing, and provided users with the flexibility of performing computations at any desired full or reduced grid resolution to suit their specific computational requirements.

  14. Feasibility Study of Optically Transparent Microstrip Patch Antenna

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Lee, Richard Q.

    1997-01-01

    The paper presents a feasibility study on optically transparent patch antennas with microstrip line and probe feeds. The two antennas operate at 2.3 GHz and 19.5 GHz respectively. They are constructed from a thin sheet of clear polyester with an AgHT-8 optically transparent conductive coating. The experimental results show good radiation patterns and input impedance match. The antennas have potential applications in mobile wireless communications.

  15. Quantum Hall effect in graphene decorated with disordered multilayer patches

    SciTech Connect

    Nam, Youngwoo; Sun, Jie Lindvall, Niclas; Kireev, Dmitry; Yurgens, August; Jae Yang, Seung; Rae Park, Chong; Woo Park, Yung

    2013-12-02

    Quantum Hall effect (QHE) is observed in graphene grown by chemical vapour deposition using platinum catalyst. The QHE is even seen in samples which are irregularly decorated with disordered multilayer graphene patches and have very low mobility (<500 cm{sup 2}V{sup −1}s{sup −1}). The effect does not seem to depend on electronic mobility and uniformity of the resulting material, which indicates the robustness of QHE in graphene.

  16. Accurate Insertion Loss Measurements of the Juno Patch Array Antennas

    NASA Technical Reports Server (NTRS)

    Chamberlain, Neil; Chen, Jacqueline; Hodges, Richard; Demas, John

    2010-01-01

    This paper describes two independent methods for estimating the insertion loss of patch array antennas that were developed for the Juno Microwave Radiometer instrument. One method is based principally on pattern measurements while the other method is based solely on network analyzer measurements. The methods are accurate to within 0.1 dB for the measured antennas and show good agreement (to within 0.1dB) of separate radiometric measurements.

  17. Analysis of cylindrical arrays of microstrip rectangular patches

    NASA Astrophysics Data System (ADS)

    da Silva, C. M.; Lumini, F.; Lacava, J. C. D.; Richards, F. P.

    1991-04-01

    A model for analysis of the radiation characteristics of cylindrical arrays of microstrip rectangular patches is presented. The model is based on the Green function for the multilayered structure calculated in the Fourier domain. The fields radiated by the array are calculated through an asymptotic expression obtained by the application of the stationary phase method. Radiation characteristics such as the directivity function, the ripple and the crosspolarization level are discussed for arrays excited in the TM(01) mode.

  18. Extended HXR Sources - Albedo Patches or Coronal Sources

    NASA Technical Reports Server (NTRS)

    Dennis, Brian R.

    2011-01-01

    Extended HXR sources in the presence of compact footpoints have been reported based on visibility amplitudes from different detectors. Attempts have been made to determine the location and extent of these sources through direct imaging. Results of this work will be described for simulated sources and for specific flares at different solar longitudes, with a discussion of the possible nature of the extended sources as either albedo patches or coronal sources or a combination of the two.

  19. Colloids with magnetic patches: synthesis and self-assembly

    NASA Astrophysics Data System (ADS)

    Sacanna, Stefano; Rossi, Laura; Irvine, William; Pine, David

    2011-03-01

    We developed a new class of colloidal particles that programmably and reversibly self-assemble into well-defined clusters by virtue of ``magnetic patches'' carrying a permanent magnetic dipole moment. The resulting clusters form spontaneously in a zero external field, and their geometry is entirely determined by the interplay between magnetic, steric, and electrostatic interactions. Imposing an external magnetic field enables the clusters to unbind or change their geometry allowing, in principle, to create materials with tunable structural arrangements.

  20. Multilevel image recognition using discriminative patches and kernel covariance descriptor

    NASA Astrophysics Data System (ADS)

    Lu, Le; Yao, Jianhua; Turkbey, Evrim; Summers, Ronald M.

    2014-03-01

    Computer-aided diagnosis of medical images has emerged as an important tool to objectively improve the performance, accuracy and consistency for clinical workflow. To computerize the medical image diagnostic recognition problem, there are three fundamental problems: where to look (i.e., where is the region of interest from the whole image/volume), image feature description/encoding, and similarity metrics for classification or matching. In this paper, we exploit the motivation, implementation and performance evaluation of task-driven iterative, discriminative image patch mining; covariance matrix based descriptor via intensity, gradient and spatial layout; and log-Euclidean distance kernel for support vector machine, to address these three aspects respectively. To cope with often visually ambiguous image patterns for the region of interest in medical diagnosis, discovery of multilabel selective discriminative patches is desired. Covariance of several image statistics summarizes their second order interactions within an image patch and is proved as an effective image descriptor, with low dimensionality compared with joint statistics and fast computation regardless of the patch size. We extensively evaluate two extended Gaussian kernels using affine-invariant Riemannian metric or log-Euclidean metric with support vector machines (SVM), on two medical image classification problems of degenerative disc disease (DDD) detection on cortical shell unwrapped CT maps and colitis detection on CT key images. The proposed approach is validated with promising quantitative results on these challenging tasks. Our experimental findings and discussion also unveil some interesting insights on the covariance feature composition with or without spatial layout for classification and retrieval, and different kernel constructions for SVM. This will also shed some light on future work using covariance feature and kernel classification for medical image analysis.

  1. Species Richness Responses to Structural or Compositional Habitat Diversity between and within Grassland Patches: A Multi-Taxon Approach

    PubMed Central

    Lengyel, Szabolcs; Déri, Eszter; Magura, Tibor

    2016-01-01

    Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD) is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR) of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary) and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals) showed that the wet-dry gradient (compositional HD at the between-patch scale) was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale) was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale) was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none) was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve biodiversity in

  2. Species Richness Responses to Structural or Compositional Habitat Diversity between and within Grassland Patches: A Multi-Taxon Approach.

    PubMed

    Lengyel, Szabolcs; Déri, Eszter; Magura, Tibor

    2016-01-01

    Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD) is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR) of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary) and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals) showed that the wet-dry gradient (compositional HD at the between-patch scale) was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale) was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale) was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none) was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve biodiversity in

  3. Polyurethane membranes for flexible centimeter-wave patch antennas

    NASA Astrophysics Data System (ADS)

    Baron, Samuel; Guiffard, Benoit; Sharaiha, Ala

    2014-07-01

    In this paper, we present the original use of a recyclable and low cost soft polymer, polyurethane (PU) (ɛr ≈ 3.5 at 10 GHz), as part of a dielectric substrate of a microstrip patch antenna. The combination of simple membrane manufacturing process and the low Young’s modulus of PU (EPU ≈ 30 MPa) are employed in an X-band antenna application in this study. The PU dielectric characterizations indicate the high loss tangent value (tan δ ≈ 0.1 at 10 GHz). Membrane supported technology is used to reduce the influence of this high loss and increase the antenna efficiency. The measurement of antenna performances such as efficiency (η ≈ 31.7%) confirms the viability of the technological process and the specific patch antenna design developed in this work. Besides, the potential of the PU-based soft patch antenna for frequency agility (3.88%) via mechanical reconfiguration is also shown.

  4. The groundwater subsidy to vegetation: groundwater exchanges between landcover patches

    NASA Astrophysics Data System (ADS)

    Steven, L. I.; Gimenez, R.; Jobbagy, E. G.

    2015-12-01

    The Gran Chaco is a hot, dry plain, that spans over 60 million hectares across Bolivia, Paraguay, Brazil and Argentina. It supports high biodiversity in its dry forest and savannahs, but is rapidly being converted to agriculture in response to growing soy demand and technology including genetic modification and zero-till, that has made cultivation in drier landscapes more viable. Under natural conditions, the deep-rooted, native vegetation of the Chaco effectively captured all rainfall for evapotranspiration resulting in near zero groundwater recharge under the dry forest. Conversion to shallower rooted soy and corn, combined with the fallow period prior to the growing season, reduces evapotranspiration and allows some water to percolate through the root zone and recharge the groundwater system. When this groundwater recharge occurs, it creates groundwater mounding and a hydraulic gradient that drives flow to adjacent landcover patches where recharge does not occur. As the watertable rises, groundwater becomes available to the deep-rooted, dry forest vegetation. We develop a soil and groundwater flow model to simulate infiltration, percolation, evaporation, rootwater uptake, groundwater recharge and the lateral transfer of water between adjacent landcover patches to quantify this groundwater subsidy from converted agricultural lands to remnant patches of dry forest.

  5. Patch Network for Power Allocation and Distribution in Smart Materials

    NASA Technical Reports Server (NTRS)

    Golembiewski, Walter T.

    2000-01-01

    The power allocation and distribution (PAD) circuitry is capable of allocating and distributing a single or multiple sources of power over multi-elements of a power user grid system. The purpose of this invention is to allocate and distribute power that is collected by individual patch rectennas to a region of specific power-user devices, such as actuators. The patch rectenna converts microwave power into DC power. Then this DC power is used to drive actuator devices. However, the power from patch rectennas is not sufficient to drive actuators unless all the collected power is effectively used to drive another group by allocation and distribution. The power allocation and distribution (PAD) circuitry solves the shortfall of power for devices in a large array. The PAD concept is based on the networked power control in which power collected over the whole array of rectennas is allocated to a sub domain where a group of devices is required to be activated for operation. Then the allocated power is distributed to individual element of power-devices in the sub domain according to a selected run-mode.

  6. Patch reef modeling: a comparison of Devonian and recent examples

    SciTech Connect

    Precht, W.F.

    1983-09-01

    In reef research, models have been developed to define variations in the lithic and biotic development of facies. Walker and Alberstadt, and Hoffman and Narkiewicz developed models for growth of ancient reef communities. Although these models form a solid foundation by which patch reefs can be classed and zoned, they are neither complete nor accurate for all reef types. A comparison was made of Lower Devonian patch reefs from the Appalachian basin of New York, New Jersey, and Pennsylvania, and Holocene examples from the Bahamas and Florida Keys to identify the structure, orientation, community variability, and succession of the reef biofacies. The complexion and genesis of the carbonate lithofacies were also studied. Results show similarities; these include the size, areal distribution, 3-D geometry, wave-resistance potential, lateral sequences of facies, sedimentary textures and structures, vertical zonation explained by growth from low-energy to high-energy regimes, biotic diversity, growth habit and form, and postmortem alteration. Thus, when used in conjunction with the traditional models, the recent can serve as the basis for a general model which include most patch reef types. However, these models should not be used as explicit analogs for all Phanerozoic reefs. Knowing and understanding the limitations of these comparative studies are essential to a fuller comprehension of the potential for variations which exist within and between the traditional models.

  7. Cleaning patch-clamp pipettes for immediate reuse

    PubMed Central

    Kolb, I.; Stoy, W. A.; Rousseau, E. B.; Moody, O. A.; Jenkins, A.; Forest, C. R.

    2016-01-01

    Patch-clamp recording has enabled single-cell electrical, morphological and genetic studies at unparalleled resolution. Yet it remains a laborious and low-throughput technique, making it largely impractical for large-scale measurements such as cell type and connectivity characterization of neurons in the brain. Specifically, the technique is critically limited by the ubiquitous practice of manually replacing patch-clamp pipettes after each recording. To circumvent this limitation, we developed a simple, fast, and automated method for cleaning glass pipette electrodes that enables their reuse within one minute. By immersing pipette tips into Alconox, a commercially-available detergent, followed by rinsing, we were able to reuse pipettes 10 times with no degradation in signal fidelity, in experimental preparations ranging from human embryonic kidney cells to neurons in culture, slices, and in vivo. Undetectable trace amounts of Alconox remaining in the pipette after cleaning did not affect ion channel pharmacology. We demonstrate the utility of pipette cleaning by developing the first robot to perform sequential patch-clamp recordings in cell culture and in vivo without a human operator. PMID:27725751

  8. Potential and problems of developing transdermal patches for veterinary applications.

    PubMed

    Riviere, J E; Papich, M G

    2001-09-01

    A new frontier in the administration of therapeutic drugs to veterinary species is transdermal drug delivery. The primary challenge in developing these systems is rooted in the wide differences in skin structure and function seen in species ranging from cats to cows. The efficacy of a transdermal system is primarily dependent upon the barrier properties of the targeted species skin, as well as the ratio of the area of the transdermal patch to the species total body mass needed to achieve effective systemic drug concentrations. A drug must have sufficient lipid solubility to traverse the epidermal barrier to be considered for delivery for this route. A number of insecticides have been developed in liquid "pour-on" formulations that illustrate the efficacy of this route of administration for veterinary species. The human transdermal fentanyl patch has been successfully used in cats and dogs for post-operative analgesia. The future development of transdermal drug delivery systems for veterinary species will be drug and species specific. With efficient experimental designs and available transdermal patch technology, there are no obvious hurdles to the development of effective systems in many veterinary species.

  9. STS-69 Crew members display 'Dog Crew' patches

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Following their arrival at KSC's Shuttle Landing Facility, the five astronauts assigned to Space Shuttle Mission STS-69 display the unofficial crew patch for their upcoming spaceflight: the Dog Crew II patch. Mission Commander David M. Walker (center) and Payload Commander James S. Voss (second from right) previously flew together on Mission STS-53, the final dedicated Department of Defense flight on the Space Shuttle. A close comradery formed among Walker, Voss and the rest of the crew, and they dubbed themselves the 'dogs of war', with each of the STS-53 'Dog Crew' members assigned a 'dog tag' or nickname. When the STS-69 astronauts also became good buddies, they decided it was time for the Dog Crew II to be named. Walker's dog tag is Red Dog, Voss's is Dogface, Pilot Kenneth D. Cockrell (second from left) is Cujo, space rookie and Mission Specialist Michael L. Gernhardt (left) is Under Dog, and Mission Specialist James H. Newman (right) is Pluato. The Dog Crew II patch features a bulldog peering out from a doghouse shaped like the Space Shuttle and lists the five crew member's dog names. The five astronauts are scheduled to lift off on the fifth Shuttle flight of the year at 11:04 a.m. EDT, August 31, aboard the Space Shuttle Endeavour.

  10. Cleaning patch-clamp pipettes for immediate reuse.

    PubMed

    Kolb, I; Stoy, W A; Rousseau, E B; Moody, O A; Jenkins, A; Forest, C R

    2016-10-11

    Patch-clamp recording has enabled single-cell electrical, morphological and genetic studies at unparalleled resolution. Yet it remains a laborious and low-throughput technique, making it largely impractical for large-scale measurements such as cell type and connectivity characterization of neurons in the brain. Specifically, the technique is critically limited by the ubiquitous practice of manually replacing patch-clamp pipettes after each recording. To circumvent this limitation, we developed a simple, fast, and automated method for cleaning glass pipette electrodes that enables their reuse within one minute. By immersing pipette tips into Alconox, a commercially-available detergent, followed by rinsing, we were able to reuse pipettes 10 times with no degradation in signal fidelity, in experimental preparations ranging from human embryonic kidney cells to neurons in culture, slices, and in vivo. Undetectable trace amounts of Alconox remaining in the pipette after cleaning did not affect ion channel pharmacology. We demonstrate the utility of pipette cleaning by developing the first robot to perform sequential patch-clamp recordings in cell culture and in vivo without a human operator.

  11. Explorationist's model of a patch-reef trap

    SciTech Connect

    Sams, R.H.

    1984-04-01

    A geologic model of a carbonate patch-reef complex is proposed. When applied to subsurface control where wells have been cored, the model is designed to actually position a well location with respect to a stratigraphic trap formed by the patch reef. The model is lithofacies governed and is based upon those facies relationships observed among several Gulf Cost patch-reef examples. The relationship between variations in effective porosity and permeability and the variations in lithofacies appears to be direct, judging from the examples studies. This direct relationship points to the formation of a permeability barrier stratigraphic trap where certain updip and lateral facies changes occur. Only primary porosity and permeability are considered by the model. The effects of secondary porosity, fracturing, dolomitization, and/or secondary cementation can be considered by a second model applied as an overprint to the first. Application of the model as an additional exploratory tool in carbonates where reservoir quality is a function of lithofacies distribution can lead to the drilling and discovery of numerous subtle stratigraphic traps.

  12. Earth's polar cap ionization patches lead to ion upflow

    NASA Astrophysics Data System (ADS)

    Zhang, Q. H.; Zong, Q.; Lockwood, M. M.; Liang, J.; Zhang, B.; Moen, J. I.; Zhang, S.; Zhang, Y.; Ruohoniemi, J. M.; Thomas, E. G.; Liu, R.; Dunlop, M. W.; Yang, H. G.; Hu, H.; Liu, Y.; Lester, M.

    2014-12-01

    The Earth constantly losses matter through ions escaping from the polar ionosphere. This makes the ionosphere as an important source of plasma for the magnetosphere and could modulate atmospheric isotope abundances on geological timescales, depending on what fraction of the upflowing ions subsequently return to the ionosphere and what fraction are ejected into interplanetary space. It has been proposed that the magnetosphere is dynamically modulated by the presence of the ionospheric ions, particularly heavy ions O+, during magnetic substorms and storms. The origin and formation mechanism of ionospheric ion upflow is, however, poorly understood, particularly under disturbed space weather conditions. We report simultaneous direct observations of ion upflow and a patch of ionization at the center of the polar cap region during a geomagnetic storm. Our observations indicate enhanced fluxes of upwelling O+ ions originate from the patch and were accelerated by the enhanced ambipolar electric field. This enhancement is caused by soft electron precipitations. Polar cap patches therefore provide an important source of upwelling ions for accelerations mechanisms at greater altitudes which can eject the ions. These observations give new insight into the processes of ionosphere-magnetosphere coupling and the potential loss of terrestrial water dissociation products into space which, although extremely slow in the case of Earth, may be significant for other planets and moons.

  13. Self-Replication of Localized Vegetation Patches in Scarce Environments

    NASA Astrophysics Data System (ADS)

    Bordeu, Ignacio; Clerc, Marcel G.; Couteron, Piere; Lefever, René; Tlidi, Mustapha

    2016-09-01

    Desertification due to climate change and increasing drought periods is a worldwide problem for both ecology and economy. Our ability to understand how vegetation manages to survive and propagate through arid and semiarid ecosystems may be useful in the development of future strategies to prevent desertification, preserve flora—and fauna within—or even make use of scarce resources soils. In this paper, we study a robust phenomena observed in semi-arid ecosystems, by which localized vegetation patches split in a process called self-replication. Localized patches of vegetation are visible in nature at various spatial scales. Even though they have been described in literature, their growth mechanisms remain largely unexplored. Here, we develop an innovative statistical analysis based on real field observations to show that patches may exhibit deformation and splitting. This growth mechanism is opposite to the desertification since it allows to repopulate territories devoid of vegetation. We investigate these aspects by characterizing quantitatively, with a simple mathematical model, a new class of instabilities that lead to the self-replication phenomenon observed.

  14. Self-Replication of Localized Vegetation Patches in Scarce Environments

    PubMed Central

    Bordeu, Ignacio; Clerc, Marcel G.; Couteron, Piere; Lefever, René; Tlidi, Mustapha

    2016-01-01

    Desertification due to climate change and increasing drought periods is a worldwide problem for both ecology and economy. Our ability to understand how vegetation manages to survive and propagate through arid and semiarid ecosystems may be useful in the development of future strategies to prevent desertification, preserve flora—and fauna within—or even make use of scarce resources soils. In this paper, we study a robust phenomena observed in semi-arid ecosystems, by which localized vegetation patches split in a process called self-replication. Localized patches of vegetation are visible in nature at various spatial scales. Even though they have been described in literature, their growth mechanisms remain largely unexplored. Here, we develop an innovative statistical analysis based on real field observations to show that patches may exhibit deformation and splitting. This growth mechanism is opposite to the desertification since it allows to repopulate territories devoid of vegetation. We investigate these aspects by characterizing quantitatively, with a simple mathematical model, a new class of instabilities that lead to the self-replication phenomenon observed. PMID:27650430

  15. Self-Replication of Localized Vegetation Patches in Scarce Environments.

    PubMed

    Bordeu, Ignacio; Clerc, Marcel G; Couteron, Piere; Lefever, René; Tlidi, Mustapha

    2016-09-21

    Desertification due to climate change and increasing drought periods is a worldwide problem for both ecology and economy. Our ability to understand how vegetation manages to survive and propagate through arid and semiarid ecosystems may be useful in the development of future strategies to prevent desertification, preserve flora-and fauna within-or even make use of scarce resources soils. In this paper, we study a robust phenomena observed in semi-arid ecosystems, by which localized vegetation patches split in a process called self-replication. Localized patches of vegetation are visible in nature at various spatial scales. Even though they have been described in literature, their growth mechanisms remain largely unexplored. Here, we develop an innovative statistical analysis based on real field observations to show that patches may exhibit deformation and splitting. This growth mechanism is opposite to the desertification since it allows to repopulate territories devoid of vegetation. We investigate these aspects by characterizing quantitatively, with a simple mathematical model, a new class of instabilities that lead to the self-replication phenomenon observed.

  16. A patch-based tensor decomposition algorithm for M-FISH image classification.

    PubMed

    Wang, Min; Huang, Ting-Zhu; Li, Jingyao; Wang, Yu-Ping

    2016-05-03

    Multiplex-fluorescence in situ hybridization (M-FISH) is a chromosome imaging technique which can be used to detect chromosomal abnormalities such as translocations, deletions, duplications, and inversions. Chromosome classification from M-FISH imaging data is a key step to implement the technique. In the classified M-FISH image, each pixel in a chromosome is labeled with a class index and drawn with a pseudo-color so that geneticists can easily conduct diagnosis, for example, identifying chromosomal translocations by examining color changes between chromosomes. However, the information of pixels in a neighborhood is often overlooked by existing approaches. In this work, we assume that the pixels in a patch belong to the same class and use the patch to represent the center pixel's class information, by which we can use the correlations of neighboring pixels and the structural information across different spectral channels for the classification. On the basis of assumption, we propose a patch-based classification algorithm by using higher order singular value decomposition (HOSVD). The developed method has been tested on a comprehensive M-FISH database that we established, demonstrating improved performance. When compared with other pixel-wise M-FISH image classifiers such as fuzzy c-means clustering (FCM), adaptive fuzzy c-means clustering (AFCM), improved adaptive fuzzy c-means clustering (IAFCM), and sparse representation classification (SparseRC) methods, the proposed method gave the highest correct classification ratio (CCR), which can translate into improved diagnosis of genetic diseases and cancers. © 2016 International Society for Advancement of Cytometry.

  17. A Randomized Trial Comparing Part-time Patching with Observation for Children 3–10 Years Old with Intermittent Exotropia

    PubMed Central

    Cotter, Susan A.; Mohney, Brian G.; Chandler, Danielle L.; Holmes, Jonathan M.; Repka, Michael X.; Melia, Michele; Wallace, David K.; Beck, Roy W.; Birch, Eileen E.; Kraker, Raymond T.; Tamkins, Susanna M.; Miller, Aaron M.; Sala, Nicholas A.; Glaser, Stephen R.

    2014-01-01

    Objective To determine the effectiveness of prescribed part-time patching for treatment of intermittent exotropia in children Design Multicenter, randomized clinical trial Participants Three hundred fifty-eight children aged 3 to < 11 years old with previously untreated (except for refractive correction) intermittent exotropia (IXT) and near stereoacuity of 400 arcsec or better were enrolled. Intermittent exotropia met the following criteria: 1) constant or intermittent exotropia at distance and either intermittent exotropia or exophoria at near; 2) exodeviation (tropia or phoria) of at least 15 prism diopters (Δ) at distance or near by prism and alternate cover test (PACT); and 3) exodeviation of at least 10Δ at distance by PACT. Methods Participants were randomly assigned to either observation (no treatment for 6 months) or patching for 3 hours per day for 5 months, with a 1-month washout period of no patching before the 6-month primary outcome exam. Main Outcome Measure The primary outcome was deterioration at either the 3-month or the 6-month follow-up visit, defined as: 1) constant exotropia measuring at least 10Δ at distance and near by simultaneous prism and cover test, and/or 2) near stereoacuity decreased by at least 2 octaves from baseline, both assessed by a masked examiner and confirmed by a retest. Participants who were prescribed any non-randomized treatment without first meeting either deterioration criteria were also counted as having deteriorated. Results Of the 324 (91%) participants completing the 6-month primary outcome exam, deterioration occurred in 10 (6.1%) of the 165 participants in the observation group (3 of these 10 started treatment without meeting deterioration criteria) and in 1 (0.6%) of the 159 participants in the part-time patching group (difference = 5.4%, lower limit of one-sided exact 95% confidence interval = 2.0%; p value from one-sided hypothesis test = 0.004). Conclusion Deterioration of previously untreated childhood IXT

  18. Planar silicon patch-clamp electrodes integrated with polydimethylsiloxane microfluidics

    NASA Astrophysics Data System (ADS)

    Nagarah, John Michael

    The patch-clamp technique allows one to probe single ion channels and macroscopic ion channel activity in their native environment and resolve their activity as their physical and chemical surroundings are varied. The traditional method of patch-clamping cells involves bringing a clean, flame-polished glass pipette tip with a 1-2 mum diameter pore into contact with a cell membrane to form a high electrical resistance seal. This technique is the gold standard for cellular electrophysiology investigations because it allows the observation of single ion channel protein dynamics as well as activity from an ensemble ion channels from a single cell. Furthermore, any drug approved by federal drug agencies must be screened against particular ion channels with the patch-clamp technique. However, this technique by its nature is serial, time consuming, difficult when exchanging pipette solutions, and difficult to integrate with other technologies. These reasons have prompted several investigators to explore alternative approaches to traditional pipette patch-clamping to increase the throughput of measurements. Herein, I describe the development of a silicon-wafer based device platform that enables the measurement of ion channel activities. The electrical nature of the cell/wafer seal is characterized for several pore design variations. The majority of gigaohm seals obtained falls in the range of 10-20GO. The cell-attached and whole cell configurations are demonstrated. Whole cell ion channel activity originating from various cell fines is consistent with the more traditional micropipette patch-clamp recordings. The silicon fabrication methods developed, although novel, utilize established semiconductor technologies, making them amenable to batch fabrication techniques. I integrate these silicon devices with PDMS microfluidics with monolithic valves, allowing ultra-fast solution exchange as low as tens of milliseconds for the extracellular solution. Furthermore, I developed a

  19. The Association Between Treatment Adherence to Nicotine Patches and Smoking Cessation in Pregnancy: A Secondary Analysis of a Randomized Controlled Trial

    PubMed Central

    Aveyard, Paul; Cooper, Sue; Leonardi-Bee, Jo; Coleman, Tim

    2016-01-01

    adherence to NRT patch treatment and odds of cessation in pregnant quitters. Greater adherence was seen with NRT patches, and greater adherence with NRT patches increased the odds of smoking cessation. A likely explanation for findings is that NRT patches, if used sufficiently, may be effective for at least some pregnant women who try to stop smoking. Trials testing interventions which encourage women’s adherence to higher dose NRT are indicated. PMID:27611311

  20. A framework for landscape ecological design of new patches in the rural landscape.

    PubMed

    Lafortezza, R; Brown, R D

    2004-10-01

    This study developed a comprehensive framework to incorporate landscape ecological principles into the landscape planning and design process, with a focus on the design of new patches in the rural landscape. The framework includes two interrelated phases: patch analyst (PA) and patch designer (PD). The patch analyst augments the process of landscape inventory and analysis. It distinguishes nodes (associated with potential habitat patches) from links (associated with corridors and stepping stones between habitats). For natural vegetation patches, characteristics such as size, shape, and spatial arrangement have been used to develop analytical tools that distinguish between nodes and links. The patch designer uses quantitative information and analytical tools to recommend locations, shapes, sizes, and composition of introduced patches. The framework has been applied to the development of a new golf course in the rural Mediterranean landscape of Apulia, Southern Italy. Fifty new patches of Mediterranean maquis (24 patches) and garrigue (26 patches) have been designed and located in the golf course, raising the overall natural vegetation area to 70 ha (60% of total property). The framework has potential for use in a wide variety of landscape planning, design, and management projects.

  1. Effect of patch borders on coercivity in amorphous rare earth-transition metal thin films

    NASA Technical Reports Server (NTRS)

    Patterson, G.; Fu, H.; Giles, R. C.; Mansuripur, M.

    1991-01-01

    The coercivity at the micron scale is a very important property of magneto-optical media. It is a key factor that determines the magnetic domain wall movement and domain reversal. How the coercivity is influenced by a special type of patch borders is discussed. Patch formation is a general phenomenon in growth processes of amorphous rare earth transition metal thin films. Different patches may stem from different seeds and the patch borders are formed when they merge. Though little is known about the exact properties of the borders, we may expect that the exchange interaction at the patch border is weaker than that within a patch, since there is usually a spatial gap between two patches. Computer simulations were performed on a 2-D hexagonal lattice consisting of 37 complete patches with random shape and size. From the series of simulations we may conclude that the domain in the patch with borders of 30 percent exchange strength can expand most easily to the whole lattice, because the exchange strength can expand most easily to the whole lattice, because the exchange strength of the border is not too high to prevent the domain from growing within the patch and it is not too low to prevent the domain from expanding beyond the patch.

  2. Periodic creation of polar cap patches from auroral transients in the cusp

    NASA Astrophysics Data System (ADS)

    Hosokawa, K.; Taguchi, S.; Ogawa, Y.

    2016-06-01

    On 24 November 2012, an interval of polar cap patches was identified by an all-sky airglow imager located near the dayside cusp. During the interval, the successive appearance of poleward moving auroral forms (PMAFs) was detected, which are known to represent ionospheric manifestations of pulsed magnetic reconnections at the dayside magnetopause. All of the patches observed during the interval appeared from these transient auroral features (i.e., there was a one-to-one correspondence between PMAFs and newly created baby patches). This fact strongly suggests that patches can be directly and seamlessly created from a series of PMAFs. The optical intensities of the baby patches were 100-150 R, which is slightly lower than typical patch luminosity on the nightside and may imply that PMAF-induced patches are generally low density. The generation of such patches could be explained by impact ionization due to soft particle precipitation into PMAFs traces. In spite of the faint signature of the baby patches, two coherent HF radars of the SuperDARN network observed backscatter echoes in the central polar cap, which represented signatures of plasma irregularities associated with the baby patches. These indicate that patches created from PMAFs have the potential to affect the satellite communications environment in the central polar cap region.

  3. Covalent modification of pericardial patches for sustained rapamycin delivery inhibits venous neointimal hyperplasia

    NASA Astrophysics Data System (ADS)

    Bai, Hualong; Lee, Jung Seok; Chen, Elizabeth; Wang, Mo; Xing, Ying; Fahmy, Tarek M.; Dardik, Alan

    2017-01-01

    Prosthetic grafts and patches are commonly used in cardiovascular surgery, however neointimal hyperplasia remains a significant concern, especially under low flow conditions. We hypothesized that delivery of rapamycin from nanoparticles (NP) covalently attached to patches allows sustained site-specific delivery of therapeutic agents targeted to inhibit localized neointimal hyperplasia. NP were covalently linked to pericardial patches using EDC/NHS chemistry and could deliver at least 360 ng rapamycin per patch without detectable rapamycin in serum; nanoparticles were detectable in the liver, kidney and spleen but no other sites within 24 hours. In a rat venous patch angioplasty model, control patches developed robust neointimal hyperplasia on the patch luminal surface characterized by Eph-B4-positive endothelium and underlying SMC and infiltrating cells such as macrophages and leukocytes. Patches delivering rapamycin developed less neointimal hyperplasia, less smooth muscle cell proliferation, and had fewer infiltrating cells but retained endothelialization. NP covalently linked to pericardial patches are a novel composite delivery system that allows sustained site-specific delivery of therapeutics; NP delivering rapamycin inhibit patch neointimal hyperplasia. NP linked to patches may represent a next generation of tissue engineered cardiovascular implants.

  4. Covalent modification of pericardial patches for sustained rapamycin delivery inhibits venous neointimal hyperplasia.

    PubMed

    Bai, Hualong; Lee, Jung Seok; Chen, Elizabeth; Wang, Mo; Xing, Ying; Fahmy, Tarek M; Dardik, Alan

    2017-01-10

    Prosthetic grafts and patches are commonly used in cardiovascular surgery, however neointimal hyperplasia remains a significant concern, especially under low flow conditions. We hypothesized that delivery of rapamycin from nanoparticles (NP) covalently attached to patches allows sustained site-specific delivery of therapeutic agents targeted to inhibit localized neointimal hyperplasia. NP were covalently linked to pericardial patches using EDC/NHS chemistry and could deliver at least 360 ng rapamycin per patch without detectable rapamycin in serum; nanoparticles were detectable in the liver, kidney and spleen but no other sites within 24 hours. In a rat venous patch angioplasty model, control patches developed robust neointimal hyperplasia on the patch luminal surface characterized by Eph-B4-positive endothelium and underlying SMC and infiltrating cells such as macrophages and leukocytes. Patches delivering rapamycin developed less neointimal hyperplasia, less smooth muscle cell proliferation, and had fewer infiltrating cells but retained endothelialization. NP covalently linked to pericardial patches are a novel composite delivery system that allows sustained site-specific delivery of therapeutics; NP delivering rapamycin inhibit patch neointimal hyperplasia. NP linked to patches may represent a next generation of tissue engineered cardiovascular implants.

  5. Covalent modification of pericardial patches for sustained rapamycin delivery inhibits venous neointimal hyperplasia

    PubMed Central

    Bai, Hualong; Lee, Jung Seok; Chen, Elizabeth; Wang, Mo; Xing, Ying; Fahmy, Tarek M.; Dardik, Alan

    2017-01-01

    Prosthetic grafts and patches are commonly used in cardiovascular surgery, however neointimal hyperplasia remains a significant concern, especially under low flow conditions. We hypothesized that delivery of rapamycin from nanoparticles (NP) covalently attached to patches allows sustained site-specific delivery of therapeutic agents targeted to inhibit localized neointimal hyperplasia. NP were covalently linked to pericardial patches using EDC/NHS chemistry and could deliver at least 360 ng rapamycin per patch without detectable rapamycin in serum; nanoparticles were detectable in the liver, kidney and spleen but no other sites within 24 hours. In a rat venous patch angioplasty model, control patches developed robust neointimal hyperplasia on the patch luminal surface characterized by Eph-B4-positive endothelium and underlying SMC and infiltrating cells such as macrophages and leukocytes. Patches delivering rapamycin developed less neointimal hyperplasia, less smooth muscle cell proliferation, and had fewer infiltrating cells but retained endothelialization. NP covalently linked to pericardial patches are a novel composite delivery system that allows sustained site-specific delivery of therapeutics; NP delivering rapamycin inhibit patch neointimal hyperplasia. NP linked to patches may represent a next generation of tissue engineered cardiovascular implants. PMID:28071663

  6. Engineered hybrid cardiac patches with multifunctional electronics for online monitoring and regulation of tissue function

    NASA Astrophysics Data System (ADS)

    Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal

    2016-06-01

    In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, freestanding electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function.

  7. Localized polar cap precipitation in association with nonstorm time airglow patches

    NASA Astrophysics Data System (ADS)

    Zou, Ying; Nishimura, Yukitoshi; Lyons, Larry R.; Shiokawa, Kazuo

    2017-01-01

    Although airglow patches are traditionally regarded as high-density ionospheric plasma unrelated to local precipitation, past observations were limited to disturbed conditions. Recent nonstorm time observations show patches to be associated with ionospheric flow channels and localized field-aligned currents. We examine whether nonstorm time patches are related also to polar cap precipitation using Fast Auroral Snapshot-imager conjunctions. We have identified localized precipitation that is enhanced within patches in comparison to the weak polar rain outside patches. The precipitation consists of structured or diffuse soft electron fluxes. While the latter resembles polar rain only with higher fluxes, the former consists of discrete fluxes enhanced by 1-2 orders of magnitude from several to several hundred eV. Therefore, patches should be regarded as part of a localized magnetosphere-ionosphere coupling system along open magnetic field lines and their transpolar evolution as a reflection of mesoscale magnetotail lobe processes. The precipitation a minor contributor to patch ionization.

  8. The modeling of piezoceramic patch interactions with shells, plates and beams

    NASA Technical Reports Server (NTRS)

    Banks, H. T.; Smith, R. C.

    1992-01-01

    General models describing the interactions between a pair of piezoceramic patches and elastic substructures consisting of a cylindrical shell, plate and beam are presented. In each case, the manner in which the patch loads enter both the strong and weak forms of the time-dependent structural equations of motion is described. Through force and moment balancing, these loads are then determined in terms of material properties of the patch and substructure (thickness, elastic properties, Poisson ratios), the geometry of the patch placement, and the voltages into the patches. In the case of the shell, the coupling between banding and inplane deformations, which is due to the curvature, is retained. These models are sufficiently general to allow for potentially different patch voltages which implies that they can be suitably employed when using piezoceramic patches for controlling system dynamics when both extensional and bending vibrations are present.

  9. Engineered hybrid cardiac patches with multifunctional electronics for online monitoring and regulation of tissue function

    PubMed Central

    Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal

    2016-01-01

    In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, free-standing electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on-demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function. PMID:26974408

  10. Patched1 functions as a gatekeeper by promoting cell cycle progression.

    PubMed

    Adolphe, Christelle; Hetherington, Rehan; Ellis, Tammy; Wainwright, Brandon

    2006-02-15

    Mutations in the Hedgehog receptor, Patched 1 (Ptch1), have been linked to both familial and sporadic forms of basal cell carcinoma (BCC), leading to the hypothesis that loss of Ptch1 function is sufficient for tumor progression. By combining conditional knockout technology with the inducible activity of the Keratin6 promoter, we provide in vivo evidence that loss of Ptch1 function from the basal cell population of mouse skin is sufficient to induce rapid skin tumor formation, reminiscent of human BCC. Elimination of Ptch1 does not promote the nuclear translocation of beta-catenin and does not induce ectopic activation or expression of Notch pathway constituents. In the absence of Ptch1, however, a large proportion of basal cells exhibit nuclear accumulation of the cell cycle regulators cyclin D1 and B1. Collectively, our data suggest that Ptch1 likely functions as a tumor suppressor by inhibiting G1-S phase and G2-M phase cell cycle progression, and the rapid onset of tumor progression clearly indicates Ptch1 functions as a "gatekeeper." In addition, we note the high frequency and rapid onset of tumors in this mouse model makes it an ideal system for testing therapeutic strategies, such as Patched pathway inhibitors.

  11. Effect of N-bromoacetamide on single sodium channel currents in excised membrane patches

    PubMed Central

    1982-01-01

    We have studied the effect of N-bromoacetamide (NBA) on the behavior of single sodium channel currents in excised patches of rat myotube membrane at 10 degree C. Inward sodium currents were activated by voltage steps from holding potentials of about -100 mV to test potentials of -40 mV. The cytoplasmic-face solution was isotonic CsF. Application of NBA or pronase to the cytoplasmic face of the membrane irreversibly removed sodium channel inactivation, as determined by averaged single-channel records. Teh lifetime of the open channel at - 40 mV was increased about 10-fold by NBA treatment without affecting the amplitude of single-channel currents. A binomial analysis was used both before and after treatment to determine the number of channels within the excised patch. NBA was shown to have little effect on activation kinetics, as determined by an examination of both the rising phase of averaged currents and measurements f the delay between the start of the pulse and the first channel opening. Our data support a kinetic model of sodium channel activation in which the rate constant leading back from the open state to the last closed state is slower than expected from a strict Hodgkin-Huxley model. The data also suggest that the normal open-channel lifetime is primarily determined by the inactivation process in the voltage range we have examined. PMID:6281357

  12. Local extinction of grassland plants: the landscape matrix is more important than patch attributes.

    PubMed

    Williams, Nicholas S G; Morgan, John W; McCarthy, Michael A; McDonnell, Mark J

    2006-12-01

    Past studies of local extinctions in fragmented habitats most often tested the influence of fragment size and isolation while ignoring how differences in the surrounding landscape matrix may govern extinction. We assessed how both the spatial attributes of remnant patches (area and isolation) and landscape factors (extent of urbanization and maximum inter-fire interval) influence the persistence of native plant species in grasslands in western Victoria, Australia. Persistence was determined in 2001 by resurveying 30 remnants first surveyed in the 1980s, and correlates of extinction were assessed using Bayesian logistic regression models. On average, 26% of populations of native species became locally extinct over two decades. Area and isolation had little effect on the probability of local extinction, but urbanization and longer maximum inter-fire intervals increased extinction risk. These findings suggest that the native grasslands studied are relatively insensitive to area- and isolation-based fragmentation effects and that short-term persistence of plant populations requires the maintenance of habitat quality. The latter is strongly influenced by the landscape matrix surrounding remnant patches through changes in fire regimes and increased exogenous disturbance.

  13. An extremely low profile, compact, and broadband tightly coupled patch array

    NASA Astrophysics Data System (ADS)

    Irci, E.; Sertel, K.; Volakis, John L.

    2012-01-01

    A tightly coupled patch array (TCPA) is introduced to realize small-size, extremely low profile planar antennas with broadband performance. Past approaches have used frequency selective surfaces (FSSs) as part of the substrate or ground plane (i.e., in passive mode) for also realizing low-profile antennas. In contrast, the proposed TCPA employs an FSS aperture as the radiating structure (i.e., array antenna). A key aspect of the TCPA is the exploitation of differences in FSSs when operating in radiating and passive modes. Tight element coupling and periodic excitation are the keys for achieving broadband operation. In this paper, a small-size, finite array is designed along with a very thin and compact feeding network. The designed TCPA resonated at 2.07 GHz with 5.6% impedance bandwidth (∣S11∣ < -10 dB), 4.4 dB realized gain (86% efficiency), and 23% gain bandwidth (3 dB drop). Of importance is that the overall aperture dimensions were only λ0/3 × λ0/3 and λ0/42 thick (including feeding network) at the midfrequency of operation. A preliminary TCPA antenna prototype was fabricated and tested. Both simulated and measured data show enhanced bandwidth as compared to the conventional microstrip patch antennas of the same size and thickness. However, as common for such extremely low profile microstrip antennas, the conductivity losses were augmented. Thus, the measured TCPA efficiency (50%) was smaller than computed.

  14. Robotic multi-well planar patch-clamp for native and primary mammalian cells

    PubMed Central

    Milligan, Carol J; Li, Jing; Sukumar, Piruthivi; Majeed, Yasser; Dallas, Mark L; English, Anne; Emery, Paul; Porter, Karen E; Smith, Andrew M; McFadzean, Ian; Beccano-Kelly, Dayne; Bahnasi, Yahya; Cheong, Alex; Naylor, Jacqueline; Zeng, Fanning; Liu, Xing; Gamper, Nikita; Jiang, Lin-Hua; Pearson, Hugh A; Peers, Chris; Robertson, Brian; Beech, David J

    2009-01-01

    Multi-well robotic planar patch-clamp has become common in drug development and safety programmes because it enables efficient and systematic testing of compounds against ion channels during voltage-clamp. It has not, however, been adopted significantly in other important areas of ion channel research, where conventional patch-clamp remains the favoured method. Here we show the wider potential of the multi-well approach with the capability for efficient intracellular solution exchange, describing protocols and success rates for recording from a range of native and primary mammalian cells derived from blood vessels, arthritic joints, and the immune and central nervous systems. The protocol involves preparing a suspension of single cells to be dispensed robotically into 4-8 microfluidic chambers each containing a glass chip with a small aperture. Under automated control, giga-seals and whole-cell access are achieved followed by pre-programmed routines of voltage paradigms and fast extracellular or intracellular solution exchange. Recording from 48 chambers usually takes 1-6 hr depending on the experimental design and yields 16-33 cell recordings. PMID:19197268

  15. Winter Soil Respiration from Different Vegetation Patches in the Yellow River Delta, China

    NASA Astrophysics Data System (ADS)

    Han, Guangxuan; Yu, Junbao; Li, Huabing; Yang, Liqiong; Wang, Guangmei; Mao, Peili; Gao, Yongjun

    2012-07-01

    Vegetation type and density exhibited a considerable patchy distribution at very local scales in the Yellow River Delta, due to the spatial variation of soil salinity and water scarcity. We proposed that soil respiration is affected by the spatial variations in vegetation type and soil chemical properties and tested this hypothesis in three different vegetation patches ( Phragmites australis, Suaeda heteroptera and bare soil) in winter (from November 2010 to April 2011). At diurnal scale, soil respiration all displayed single-peak curves and asymmetric patterns in the three vegetation patches; At seasonal scale, soil respiration all declined steadily until February, and then increased to a peak in next April. But, the magnitude of soil respiration showed significant differences among the three sites. Mean soil respiration rates in winter were 0.60, 0.45 and 0.17 μmol CO2 m-2 s-1 for the Phragmites australis, Suaeda heteroptera and bare soil, respectively. The combined effect of soil temperature and soil moisture accounted for 58-68 % of the seasonal variation of winter soil respiration. The mean soil respiration revealed positive and linear correlations with total N, total N and SOC storages at 0-20 cm depth, and plant biomass among the three sites. We conclude that the patchy distribution of plant biomass and soil chemical properties (total C, total N and SOC) may affect decomposition rate of soil organic matter in winter, thereby leading to spatial variations in soil respiration.

  16. Pre-clinical Experience with a Multi-Chordal Patch for Mitral Valve Repair.

    PubMed

    Chawla, Surendra K; Shi, Weiwei; McIver, Bryant V; Vinten-Johansen, Jakob; Frater, Robert W M; Padala, Muralidhar

    2016-04-01

    Surgical repair of flail mitral valve leaflets with neochordoplasty has good outcomes, but implementing it in anterior and bi-leaflet leaflet repair is challenging. Placing and sizing individual neochordae is time consuming and error prone, with persistent localized flail if performed incorrectly. In this study, we report our pre-clinical experience with a novel multi-chordal patch for mitral valve repair. The device was designed based on human cadaver hearts, and laser cut from expanded polytetrafluoroethylene. The prototypes were tested in: (stage 1) ex vivo hearts with leaflet flail (N = 6), (stage 2) acute swine induced with flail (N = 6), and (stage 3) two chronic swine survived to 23 and 120 days (N = 2). A2 and P2 prolapse were successfully repaired with coaptation length restored to 8.1 ± 2.2mm after posterior repair and to 10.2 ± 1.3mm after anterior repair in ex vivo hearts. In vivo, trace regurgitation was seen after repair with excellent patch durability, healing, and endothelialization at euthanasia. A new device for easier mitral repair is reported, with good early pre-clinical outcomes.

  17. Exploiting the richest patch has a fitness pay-off for the migratory swift parrot.

    PubMed

    Stojanovic, Dejan; Terauds, Aleks; Westgate, Martin J; Webb, Matthew H; Roshier, David A; Heinsohn, Robert

    2015-09-01

    1. Unlike philopatric migrants, the ecology of nomadic migrants is less well understood. This life-history strategy reflects responses to spatiotemporal variation in resource availability and the need to find resource rich patches to initiate breeding. The fitness consequences of movements between regions of patchily distributed resources can provide insight into ecology of all migrants and their responses to global change. 2. We link broad-scale data on spatiotemporal fluctuation in food availability to data on settlement patterns and fitness outcomes for a nomadic migrant, the endangered swift parrot Lathamus discolor. We test several predictions to determine whether facultative movements are adaptive for individual swift parrots in an environment where resources are patchily distributed over time and space. 3. Variation in the availability of swift parrot food resources across our study period was dramatic. As a consequence, swift parrots moved to breed wherever food was most abundant and did not resettle nesting regions in successive years when food availability declined. By moving, swift parrots exploited a variable food resource and reproduced successfully. 4. Exploiting the richest patches allowed swift parrots to maintain stable fitness outcomes between discrete breeding events at different locations. Unlike sedentary species that often produce few or lower quality offspring when food is scarce, nomadic migration buffered swift parrots against extreme environmental variation. 5. We provide the first detailed evidence that facultative movements and nomadic migration are adaptive for individuals in unpredictable environments. Our data support the widely held assumption that nomadic migration allows animals to escape resource limitation.

  18. Single dose pharmacokinetics of the novel transdermal donepezil patch in healthy volunteers

    PubMed Central

    Kim, Yo Han; Choi, Hee Youn; Lim, Hyeong-Seok; Lee, Shi Hyang; Jeon, Hae Sun; Hong, Donghyun; Kim, Seong Su; Choi, Young Kweon; Bae, Kyun-Seop

    2015-01-01

    Background Donepezil is an acetylcholinesterase inhibitor indicated for Alzheimer’s disease. The aim of this randomized, single-blind, placebo-controlled, single-dose, dose-escalation study was to investigate the safety, tolerability, and pharmacokinetics of the donepezil patch in healthy male subjects. Methods Each healthy male subject received a single transdermal donepezil patch (72 hours patch-on periods) of 43.75 mg/12.5 cm2, 87.5 mg/25 cm2, or 175 mg/50 cm2. Serial blood samples were collected up to 312 hours after patch application. The plasma concentrations of donepezil were determined by using a validated liquid chromatography–tandem mass spectrometry method. Pharmacokinetic parameters were obtained by noncompartmental analysis. Tolerability of the patches and performance of the patches (adhesion, skin irritation, residual donepezil content in the patch) were assessed throughout the study. Results The study was completed by 36 healthy subjects. After patch application, the maximal plasma donepezil concentration (Cmax) and the area under the curve (AUC) increased in a dose-proportional manner. Median time to Cmax was ~74–76 hours (~2–4 hours after patch removal), and mean t1/2β was ~63.77–93.07 hours. The average donepezil residue in the patch after 72 hours was ~73.9%–86.7% of the loading dose. There were neither serious adverse events nor adverse events that lead to discontinuation. Skin adhesion of the patch was good in 97.2% of the subjects. All skin irritations after patch removal were mild and were resolved during the study period. Conclusion The donepezil patch appeared to be generally well tolerated and adhesive. Pharmacokinetic analysis of the donepezil patch demonstrated linear kinetics. PMID:25792802

  19. Ecophysiological responses to different forest patch type of two codominant tree seedlings

    PubMed Central

    Duan, Renyan; Huang, Minyi; Kong, Xiaoquan; Wang, Zhigao; Fan, Weiyi

    2015-01-01

    According to gap-phase dynamics theory, forests can be divided into four distinct patch types: gap patch (G), building patch (B), mature patch (M), and degeneration patch (D). Varying light conditions across patch types are one of the most important factors affecting the coexistence of vegetation. Mechanisms of coexistence can be understood through detailed knowledge of ecophysiological responses of codominant tree seedlings to patch types. The following study was conducted to determine ecophysiological responses of Cyclobalanopsis glauca (an evergreen broad-leaved species) and Bothrocaryum controversum (a deciduous broad-leaved species) to four different patch types. During the gap-phase dynamics, light intensity and the magnitude of change in the four different patches followed the order of: G > B > D > M. Both species had the greatest photosynthetic capacity in the G patch. Dry leaf mass per area (LMA), Chlorophyll a + b concentration (Chl), carotenoids (Car), and nitrogen content per area (Na) all responded to changes in light across patch type, but B. controversum showed greater sensitivity and changes than C. glauca. From G to M patch, the maximal quantum efficiency of PSII (Fv/Fm) had a larger variation magnitude for B. controversum than for C. glauca. From G to M patch, B. controversum showed significant changes in gas exchange, while C. glauca showed only small changes. Ecophysiological trait partitioning of response to light in different patches provides a possible explanation of a coexistence mechanism. PMID:25691956

  20. Large-scale experimental landscapes reveal distinctive effects of patch shape and connectivity on arthropod communities.

    SciTech Connect

    Orrock, John, L.; Curler, Gregory, R.; Danielson, Brent, J.; Coyle, David. R.

    2011-09-14

    The size, shape, and isolation of habitat patches can affect organism behavior and population dynamics, but little is known about the relative role of shape and connectivity in affecting ecological communities at large spatial scales. Using six sampling sessions from July 2001 until August 2002, we collected 33,685 arthropods throughout seven 12-ha experimental landscapes consisting of clear-cut patches surrounded by a matrix of mature pine forest. Patches were explicitly designed to manipulate connectivity (via habitat corridors) independently of area and edge effects. We found that patch shape, rather than connectivity, affected ground-dwelling arthropod richness and beta diversity (i.e. turnover of genera among patches). Arthropod communities contained fewer genera and exhibited less turnover in high-edge connected and high-edge unconnected patches relative to low-edge unconnected patches of similar area. Connectivity, rather than patch shape, affected the evenness of ground-dwelling arthropod communities; regardless of patch shape, high-edge connected patches had lower evenness than low- or high-edge unconnected patches. Among the most abundant arthropod orders, increased richness in low-edge unconnected patches was largely due to increased richness of Coleoptera, whereas Hymenoptera played an important role in the lower evenness in connected patches and patterns of turnover. These findings suggest that anthropogenic habitat alteration can have distinct effects on ground-dwelling arthropod communities that arise due to changes in shape and connectivity. Moreover, this work suggests that corridors, which are common conservation tools that change both patch shape and connectivity, can have multiple effects on arthropod communities via different mechanisms, and each effect may alter components of community structure.