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Sample records for multiple consecutive adhesive

  1. Percutaneous Vertebroplasty in Multiple Myeloma: Prospective Long-Term Follow-Up in 106 Consecutive Patients

    SciTech Connect

    Anselmetti, Giovanni Carlo Manca, Antonio; Montemurro, Filippo; Hirsch, Joshua; Chiara, Gabriele; Grignani, Giovanni Carnevale Schianca, Fabrizio Capaldi, Antonio Rota Scalabrini, Delia; Sardo, Elena Debernardi, Felicino; Iussich, Gabriella; Regge, Daniele

    2012-02-15

    Purpose: Percutaneous vertebroplasty (PV) is a minimally invasive procedure involving the injection of bone cement within a collapsed vertebral body. Although this procedure was demonstrated to be effective in osteoporosis and metastases, few studies have been reported in cases of multiple myeloma (MM). We prospectively evaluated the safety and efficacy of PV in the treatment of vertebral compression fractures (VCFs) resulting from MM. Materials and Methods: PV was performed in 106 consecutive MM patients who had back pain due to VCFs, the treatment of which had failed conservative therapies. Follow-up (28.2 {+-} 12.1 months) was evaluated at 7 and 15 days as well as at 1, 3, 6, 12, 18, and every 6 months after PV. Visual analog scale (VAS) pain score, opioid use, external brace support, and Oswestry Disability Index (ODI) score were recorded. Results: The median pretreatment VAS score of 9 (range 4-10) significantly (P < 0.001) decreased to 1 (range 0-9) after PV. Median pre-ODI values of 82% (range 36-89%) significantly improved to 7% (range 0-82%) (P < 0.001). Differences in pretreatment and posttreatment use of analgesic drug were statistically significant (P < 0.001). The majority of patients (70 of 81; 86%) did not use an external brace after PV (P < 0.001). Conclusion: PV is a safe, effective, and long-lasting procedure for the treatment of vertebral compression pain resulting from MM.

  2. Electrostatic adhesion of multiple non-uniformly charged dielectric particles

    NASA Astrophysics Data System (ADS)

    Kemp, B. A.; Whitney, J. G.

    2013-01-01

    Charged particle adhesion measurements can be as much as one order of magnitude higher than theoretical calculations. This discrepancy has ignited a debate as to the nature of the physics occurring with microscopic particle adhesion. Attempts to bring calculations closer to measured results have produced models that include multiple particle interactions, dielectric polarization, and non-uniform charge. Individually, each of these models can only produce a 2× to 5× enhancement in predicted adhesion force over simple Coulombic attraction. In this correspondence, an analytical model of electrostatic particle forces is developed, which allows for independent assignment of dielectric constant and non-uniform surface charge distribution to an arbitrary number of particles. Because the model can include an image plane, it is ideal for electrostatic adhesion calculations. Application to a monolayer of printed toner particles predicts nearly an order of magnitude increase in adhesion force over Coulombic attraction. These results are the first analytical results to place predictions of charged particle adhesion on the same order of magnitude with measurements.

  3. Human DNA Polymerase ϵ Is Able to Efficiently Extend from Multiple Consecutive Ribonucleotides*

    PubMed Central

    Göksenin, A. Yasemin; Zahurancik, Walter; LeCompte, Kimberly G.; Taggart, David J.; Suo, Zucai; Pursell, Zachary F.

    2012-01-01

    Replicative DNA polymerases (Pols) help to maintain the high fidelity of replication in large part through their strong selectivity against mispaired deoxyribonucleotides. It has recently been demonstrated that several replicative Pols from yeast have surprisingly low selectivity for deoxyribonucleotides over their analogous ribonucleotides. In human cells, ribonucleotides are found in great abundance over deoxyribonucleotides, raising the possibility that ribonucleotides are incorporated in the human genome at significant levels during normal cellular functions. To address this possibility, the ability of human DNA polymerase ϵ to incorporate ribonucleotides was tested. At physiological concentrations of nucleotides, human Pol ϵ readily inserts and extends from incorporated ribonucleotides. Almost half of inserted ribonucleotides escape proofreading by 3′ → 5′ exonuclease-proficient Pol ϵ, indicating that ribonucleotide incorporation by Pol ϵ is likely a significant event in human cells. Human Pol ϵ is also efficient at extending from primers terminating in up to five consecutive ribonucleotides. This efficient extension appears to result from reduced exonuclease activity on primers containing consecutive 3′-terminal ribonucleotides. These biochemical properties suggest that Pol ϵ is a likely source of ribonucleotides in human genomic DNA. PMID:23093410

  4. Rapid chemiluminescent sandwich enzyme immunoassay capable of consecutively quantifying multiple tumor markers in a sample.

    PubMed

    Kim, Julie; Kim, Jennie; Rho, Tae Ho D; Lee, Ji Hoon

    2014-11-01

    Using the role of p-iodophenol in enzyme assay, enhanced 1,1'-oxalyldiimidazole chemiluminescent enzyme immunoassays (ODI-CLEIAs) were developed to consecutively quantify trace levels of triple tumor markers, such as alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), and prostate specific antigen (PSA) in a sample. Due to the high sensitivity of enhanced ODI-CLEIAs, it was possible to fix the incubation times (1) to capture a tumor marker with two antibodies, which are primary antibody immobilized on the surface of polystyrene strip-well and detection antibody-conjugated horseradish peroxidase (HRP), and (2) to form resorufin with the addition of substrates (e.g., Amplex Red, H2O2) in order to quantify triple markers in human serum. Enhanced ODI-CLEIAs capable of consecutively and rapidly quantifying triple markers with the same incubation time were more sensitive than conventional enzyme-linked immunosorbent assay (ELISA) capable of separately and slowly quantifying them with different incubation times. In addition, accuracy, precision, and recovery of enhanced ODI CLEIAs in the presence of p-iodophenol were acceptable within statistical error range. PMID:25127571

  5. Split-Volume Treatment Planning of Multiple Consecutive Vertebral Body Metastases for Cyberknife Image-Guided Robotic Radiosurgery

    SciTech Connect

    Sahgal, Arjun Chuang, Cynthia; Larson, David; Huang, Kim; Petti, Paula; Weinstein, Phil; Ma Lijun

    2008-10-01

    Cyberknife treatment planning of multiple consecutive vertebral body metastases is challenging due to large target volumes adjacent to critical normal tissues. A split-volume treatment planning technique was developed to improve the treatment plan quality of such lesions. Treatment plans were generated for 1 to 5 consecutive thoracic vertebral bodies (CVBM) prescribing a total dose of 24 Gy in 3 fractions. The planning target volume (PTV) consisted of the entire vertebral body(ies). Treatment plans were generated considering both the de novo clinical scenario (no prior radiation), imposing a dose limit of 8 Gy to 1 cc of spinal cord, and the retreatment scenario (prior radiation) with a dose limit of 3 Gy to 1 cc of spinal cord. The split-volume planning technique was compared with the standard full-volume technique only for targets ranging from 2 to 5 CVBM in length. The primary endpoint was to obtain best PTV coverage by the 24 Gy prescription isodose line. A total of 18 treatment plans were generated (10 standard and 8 split-volume). PTV coverage by the 24-Gy isodose line worsened consistently as the number of CVBM increased for both the de novo and retreatment scenario. Split-volume planning was achieved by introducing a 0.5-cm gap, splitting the standard full-volume PTV into 2 equal length PTVs. In every case, split-volume planning resulted in improved PTV coverage by the 24-Gy isodose line ranging from 4% to 12% for the de novo scenario and, 8% to 17% for the retreatment scenario. We did not observe a significant trend for increased monitor units required, or higher doses to spinal cord or esophagus, with split-volume planning. Split-volume treatment planning significantly improves Cyberknife treatment plan quality for CVBM, as compared to the standard technique. This technique may be of particular importance in clinical situations where stringent spinal cord dose limits are required.

  6. Adhesion

    MedlinePlus

    ... adhesions Ovarian cyst References Munireddy S, Kavalukas SL, Barbul A. Intra-abdominal healing: gastrointestinal tract and adhesions. Surg Clin N Am Kulaylat MN, Dayton, MT. Surgical complications. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, ...

  7. Cell-matrix adhesion characterization using multiple shear stress zones in single stepwise microchannel

    NASA Astrophysics Data System (ADS)

    Kim, Min-Ji; Doh, Il; Bae, Gab-Yong; Cha, Hyuk-Jin; Cho, Young-Ho

    2014-08-01

    This paper presents a cell chip capable to characterize cell-matrix adhesion by monitoring cell detachment rate. The proposed cell chip can supply multiple levels of shear stress in single stepwise microchannel. As epithelial-mesenchymal transition (EMT), one of hallmarks of cancer metastasis is closely associated to the interaction with extracelluar matrix (ECM), we took advantage of two lung cancer cell models with different adhesion properties to ECM depending their epithelial or mesenchymal properties, including the pair of lung cancer cells with (A549sh) or without E-cadherin expression (A549sh-Ecad), which would be optimal model to examine the alteration of adhesion properties after EMT induction. The cell-matrix adhesion resisting to shear stress appeared to be remarkably differed between lung cancer cells. The detachment rate of epithelial-like H358 and mesenchymal-like H460 cells was 53%-80% and 25%-66% in the shear stress range of 34-60 dyn/cm2, respectively. A549sh-Ecad cells exhibits lower detachment rate (5%-9%) compared to A549sh cells (14%-40%). By direct comparison of adhesion between A549sh and A549sh-Ecad, we demonstrated that A549shE-cad to mimic EMT were more favorable to the ECM attachment under the various levels of shear stress. The present method can be applied to quantitative analysis of tumor cell-ECM adhesion.

  8. RBQ3 participates in multiple myeloma cell proliferation, adhesion and chemoresistance.

    PubMed

    Liu, Hong; Ding, Linlin; Shen, Yaodong; Zhong, Fei; Wang, Qiru; Xu, Xiaohong

    2016-10-01

    Cell adhesion mediated drug resistance (CAM-DR) is a major factor that impedes the effect of chemotherapy in multiple myeloma (MM). RBQ3, which is a RB-binding protein, played a crucial role in cell cycle process. Here, we reported that RBQ3 expression was increased gradually during the proliferation process of myeloma cells. Knocking down of RBQ3 resulted in cell cycle arrest in G1 phase and increased myeloma cells adherent to fibronectin or bone marrow stromal cells (BMSCs). Furthermore, silencing of RBQ3 reduced sensitivity to chemotherapeutic drugs in myeloma cell lines adherent to BMSCs and reduced two apoptotic marker proteins cleaved caspase-3 and cleaved PARP expression. Besides, we also found that RBQ3 participated in MAPK/ERK signal transduction pathway. In summary, these results may shed new insights into the role of RBQ3 in the development of multiple myeloma. PMID:27189701

  9. Efficacy of Anastrozole in a Consecutive Series of Advanced Breast Cancer Patients Treated with Multiple Prior Chemotherapies and Endocrine Agents: M. D. Anderson Cancer Center Experience.

    PubMed

    Knoche, A. Jolynn; Michaud, Laura Boehnke; Buzdar, Aman U.

    1999-05-01

    Anastrozole is a highly selective, nonsteroidal aromatase inhibitor approved by the U.S. Food and Drug Administration (FDA) in January 1996 for the treatment of advanced breast cancer in postmenopausal women with disease progression following tamoxifen therapy. To date, information on anastrozole's use has been limited to breast cancer patients with minimal prior therapy. The purpose of this review was to determine, in clinical practice, the benefits of anastrozole in advanced breast cancer patients treated with multiple prior cytotoxic and endocrine therapies. This was a retrospective review of a consecutive series of 117 patients who received anastrozole after marketing in January 1996. As this was not a prospective study, rigorous response criteria could not be applied. Responses were categorized as improvement in disease (ID), stable disease (SD), or progressive disease (PD). One hundred eight patients were evaluable for response with a median age of 61 years and the number of prior therapies ranging from one to nine. Response, defined as improvement of disease or stable disease >/=8 weeks, was seen in 59% of patients. Patients with three or more prior endocrine therapies demonstrated a 61% response (ID + SD) and patients with ER-negative tumors demonstrated 50% response. Patients with prior aminoglutethamide therapy exhibited similar response rates to the overall group. One male patient received anastrozole without benefit. This data determines the activity of anastrozole even in heavily pretreated patients and suggests that patients who have tumors that are ER-negative may also benefit from anastrozole therapy. PMID:11348281

  10. Epigenetic mechanisms of cell adhesion-mediated drug resistance in multiple myeloma.

    PubMed

    Furukawa, Yusuke; Kikuchi, Jiro

    2016-09-01

    Multiple myeloma cells acquire the resistance to anti-cancer drugs through physical and functional interactions with the bone marrow microenvironment via two overlapping mechanisms. First, bone marrow stromal cells (BMSCs) produce soluble factors, such as interleukin-6 and insulin-like growth factor-1, to activate signal transduction pathways leading to drug resistance (soluble factor-mediated drug resistance). Second, BMSCs up-regulate the expression of cell cycle inhibitors, anti-apoptotic members of the Bcl-2 family and ABC drug transporters in myeloma cells upon direct adhesion [cell adhesion-mediated drug resistance (CAM-DR)]. Elucidation of the mechanisms underlying drug resistance may greatly contribute to the advancement of cancer therapies. Recent investigations, including ours, have revealed the involvement of epigenetic alterations in drug resistance especially CAM-DR. For example, we found that class I histone deacetylases (HDACs) determine the sensitivity of proteasome inhibitors and the histone methyltransferase EZH2 regulates the transcription of anti-apoptotic genes during the acquisition of CAM-DR by myeloma cells. In addition, another histone methyltransferase MMSET was shown to confer drug resistance to myeloma cells by facilitating DNA repair. These findings provide a rationale for the inclusion of epigenetic drugs, such as HDAC inhibitors and histone methylation modifiers, in combination chemotherapy for MM patients to increase the therapeutic index. PMID:27411688

  11. Mono- and multiple TiN(/Ti) coating adhesion mechanism on a Ti-13Nb-13Zr alloy

    NASA Astrophysics Data System (ADS)

    Li, Jianzhong; Zheng, Hua; Sinkovits, Theo; Hee, Ay Ching; Zhao, Yue

    2015-11-01

    Mono- and multiple TiN(/Ti) coatings deposited on Ti-13Nb-13Zr alloy substrates by the filtered arc deposition system were examined using scratch testing and depth-sensing indentation in terms of the relationship between the coating adhesion, deformation mechanism, and microstructure, and mechanical properties at the film/substrate interface. The results show that multilayer TiN/Ti coatings offer a greater resistance to cracking and delamination than monolithic TiN coatings under the same conditions on the Ti-13Nb-13Zr alloys substrates. And increasing the number of layers for TiN multilayer coating improves the coatings adhesion. In contrast, for the coatings on the Ti-13Nb-13Zr alloys substrates that were heat-treated to a higher hardness, the limited deformation in the substrates improved remarkably the coating adhesion indiscriminately. The substrate mechanical properties play the major roles in controlling the coating adhesion, and increasing thickness and layers of the TiN multilayer have a limited improvement to the adhesion of coating.

  12. Reelin promotes the adhesion and drug resistance of multiple myeloma cells via integrin β1 signaling and STAT3

    PubMed Central

    Lv, Meng; Liang, Xiaodong; Dai, Hui; Qin, Xiaodan; Zhang, Yan; Hao, Jie; Sun, Xiuyuan; Yin, Yanhui; Huang, Xiaojun; Zhang, Jun; Lu, Jin; Ge, Qing

    2016-01-01

    Reelin is an extracellular matrix (ECM) protein that is essential for neuron migration and positioning. The expression of reelin in multiple myeloma (MM) cells and its association with cell adhesion and survival were investigated. Overexpression, siRNA knockdown, and the addition of recombinant protein of reelin were used to examine the function of reelin in MM cells. Clinically, high expression of reelin was negatively associated with progression-free survival and overall survival. Functionally, reelin promoted the adhesion of MM cells to fibronectin via activation of α5β1 integrin. The resulting phosphorylation of Focal Adhesion Kinase (FAK) led to the activation of Src/Syk/STAT3 and Akt, crucial signaling molecules involved in enhancing cell adhesion and protecting cells from drug-induced cell apoptosis. These findings indicate reelin's important role in the activation of integrin-β1 and STAT3/Akt pathways in multiple myeloma and highlight the therapeutic potential of targeting reelin/integrin/FAK axis. PMID:26848618

  13. Sums of Consecutive Integers

    ERIC Educational Resources Information Center

    Pong, Wai Yan

    2007-01-01

    We begin by answering the question, "Which natural numbers are sums of consecutive integers?" We then go on to explore the set of lengths (numbers of summands) in the decompositions of an integer as such sums.

  14. RNAi targeting multiple cell adhesion molecules reduces immune cell recruitment and vascular inflammation after myocardial infarction.

    PubMed

    Sager, Hendrik B; Dutta, Partha; Dahlman, James E; Hulsmans, Maarten; Courties, Gabriel; Sun, Yuan; Heidt, Timo; Vinegoni, Claudio; Borodovsky, Anna; Fitzgerald, Kevin; Wojtkiewicz, Gregory R; Iwamoto, Yoshiko; Tricot, Benoit; Khan, Omar F; Kauffman, Kevin J; Xing, Yiping; Shaw, Taylor E; Libby, Peter; Langer, Robert; Weissleder, Ralph; Swirski, Filip K; Anderson, Daniel G; Nahrendorf, Matthias

    2016-06-01

    Myocardial infarction (MI) leads to a systemic surge of vascular inflammation in mice and humans, resulting in secondary ischemic complications and high mortality. We show that, in ApoE(-/-) mice with coronary ligation, increased sympathetic tone up-regulates not only hematopoietic leukocyte production but also plaque endothelial expression of adhesion molecules. To counteract the resulting arterial leukocyte recruitment, we developed nanoparticle-based RNA interference (RNAi) that effectively silences five key adhesion molecules. Simultaneously encapsulating small interfering RNA (siRNA)-targeting intercellular cell adhesion molecules 1 and 2 (Icam1 and Icam2), vascular cell adhesion molecule 1 (Vcam1), and E- and P-selectins (Sele and Selp) into polymeric endothelial-avid nanoparticles reduced post-MI neutrophil and monocyte recruitment into atherosclerotic lesions and decreased matrix-degrading plaque protease activity. Five-gene combination RNAi also curtailed leukocyte recruitment to ischemic myocardium. Therefore, targeted multigene silencing may prevent complications after acute MI. PMID:27280687

  15. Evidence of a Role for CD44 and Cell Adhesion in Mediating Resistance to Lenalidomide in Multiple Myeloma: Therapeutic Implications

    PubMed Central

    Bjorklund, Chad C.; Baladandayuthapani, Veerabhadran; Lin, Heather Y.; Jones, Richard J.; Kuiatse, Isere; Wang, Hua; Yang, Jing; Shah, Jatin J.; Thomas, Sheeba K.; Wang, Michael; Weber, Donna M.; Orlowski, Robert Z.

    2013-01-01

    Resistance of myeloma to lenalidomide is an emerging clinical problem, and though it has been associated in part with activation of Wnt/β-catenin signaling, the mediators of this phenotype remained undefined. Lenalidomide-resistant models were found to overexpress the hyaluronan (HA)-binding protein CD44, a downstream Wnt/β-catenin transcriptional target. Consistent with a role of CD44 in cell adhesion-mediated drug-resistance (CAM-DR), lenalidomide-resistant myeloma cells were more adhesive to bone marrow stroma and HA-coated plates. Blockade of CD44 with monoclonal antibodies, free HA, or CD44 knockdown reduced adhesion and sensitized to lenalidomide. Wnt/β-catenin suppression by FH535 enhanced the activity of lenalidomide, as did interleukin-6 neutralization with siltuximab. Notably, all-trans-retinoic acid (ATRA) down-regulated total β-catenin, cell-surface and total CD44, reduced adhesion of lenalidomide-resistant myeloma cells, and enhanced the activity of lenalidomide in a lenalidomide-resistant in vivo murine xenograft model. Finally, ATRA sensitized primary myeloma samples from patients that had relapsed and/or refractory disease after lenalidomide therapy to this immunomodulatory agent ex vivo. Taken together, our findings support the hypotheses that CD44 and CAM-DR contribute to lenalidomide-resistance in multiple myeloma, that CD44 should be evaluated as a putative biomarker of sensitivity to lenalidomide, and that ATRA or other approaches that target CD44 may overcome clinical lenalidomide resistance. PMID:23760401

  16. Normalizing the bone marrow microenvironment with p38 inhibitor reduces multiple myeloma cell proliferation and adhesion and suppresses osteoclast formation

    SciTech Connect

    Nguyen, Aaron N.; Stebbins, Elizabeth G.; Henson, Margaret; O'Young, Gilbert; Choi, Sun J.; Quon, Diana; Damm, Debby; Reddy, Mamatha; Ma, Jing Y.; Haghnazari, Edwin; Kapoun, Ann M.; Medicherla, Satyanarayana; Protter, Andy; Schreiner, George F.; Kurihara, Noriyoshi; Anderson, Judy; Roodman, G. David; Navas, Tony A.; Higgins, Linda S. . E-mail: lhiggin3@scius.jnj.com

    2006-06-10

    The multiple myeloma (MM) bone marrow (BM) microenvironment plays a critical role in supporting tumor growth and survival as well as in promoting formation of osteolytic lesions. Recent results suggest that the p38 mitogen-activated protein kinase (MAPK) is an important factor in maintaining this activated environment. In this report, we demonstrate that the p38{alpha} MAPK inhibitor, SCIO-469, suppresses secretion of the tumor-supportive factors IL-6 and VEGF from BM stromal cells (BMSCs) as well as cocultures of BMSCs with MM cells, resulting in reduction in MM cell proliferation. Additionally, we show that SCIO-469 prevents TNF{alpha}-induced adhesion of MM cells to BMSCs through an ICAM-1- and VCAM-1-independent mechanism. Microarray analysis revealed a novel set of TNF{alpha}-induced chemokines in BMSCs that is strongly inhibited by SCIO-469. Furthermore, reintroduction of chemokines CXCL10 and CCL8 to BMSCs overcomes the inhibitory effect of SCIO-469 on TNF{alpha}-induced MM adhesion. Lastly, we show that SCIO-469 inhibits secretion and expression of the osteoclast-activating factors IL-11, RANKL, and MIP-1{alpha} as well as prevents human osteoclast formation in vitro. Collectively, these results suggest that SCIO-469 treatment can suppress factors in the bone marrow microenvironment to inhibit MM cell proliferation and adhesion and also to alleviate osteolytic activation in MM.

  17. Loss of laminin alpha 1 results in multiple structural defects and divergent effects on adhesion during vertebrate optic cup morphogenesis.

    PubMed

    Bryan, Chase D; Chien, Chi-Bin; Kwan, Kristen M

    2016-08-15

    The vertebrate eye forms via a complex set of morphogenetic events. The optic vesicle evaginates and undergoes transformative shape changes to form the optic cup, in which neural retina and retinal pigmented epithelium enwrap the lens. It has long been known that a complex, glycoprotein-rich extracellular matrix layer surrounds the developing optic cup throughout the process, yet the functions of the matrix and its specific molecular components have remained unclear. Previous work established a role for laminin extracellular matrix in particular steps of eye development, including optic vesicle evagination, lens differentiation, and retinal ganglion cell polarization, yet it is unknown what role laminin might play in the early process of optic cup formation subsequent to the initial step of optic vesicle evagination. Here, we use the zebrafish lama1 mutant (lama1(UW1)) to determine the function of laminin during optic cup morphogenesis. Using live imaging, we find, surprisingly, that loss of laminin leads to divergent effects on focal adhesion assembly in a spatiotemporally-specific manner, and that laminin is required for multiple steps of optic cup morphogenesis, including optic stalk constriction, invagination, and formation of a spherical lens. Laminin is not required for single cell behaviors and changes in cell shape. Rather, in lama1(UW1) mutants, loss of epithelial polarity and altered adhesion lead to defective tissue architecture and formation of a disorganized retina. These results demonstrate that the laminin extracellular matrix plays multiple critical roles regulating adhesion and polarity to establish and maintain tissue structure during optic cup morphogenesis. PMID:27339294

  18. Consecutive combined response spectrum

    NASA Astrophysics Data System (ADS)

    Xu, Longjun; Zhao, Guochen; Liu, Qingyang; Xie, Yujian; Xie, Lili

    2014-12-01

    Appropriate estimates of earthquake response spectrum are essential for design of new structures, or seismic safety evaluation of existing structures. This paper presents an alternative procedure to construct design spectrum from a combined normalized response spectrum (NRSC) which is obtained from pseudo-velocity spectrum with the ordinate scaled by different peak ground amplitudes (PGA, PGV, PGD) in different period regions. And a consecutive function f( T) used to normalize the ordinates is defined. Based on a comprehensive study of 220 strong ground motions recorded during recent eleven large worldwide earthquakes, the features of the NRSC are discussed and compared with the traditional normalized acceleration, velocity and displacement response spectra (NRSA, NRSV, NRSD). And the relationships between ground amplitudes are evaluated by using a weighted mean method instead of the arithmetic mean. Then the NRSC is used to define the design spectrum with given peak ground amplitudes. At last, the smooth spectrum is compared with those derived by the former approaches, and the accuracy of the proposed spectrum is tested through an analysis of the dispersion of ground motion response spectra.

  19. RANK-RANKL interactions are involved in cell adhesion-mediated drug resistance in multiple myeloma cell lines.

    PubMed

    Tsubaki, Masanobu; Takeda, Tomoya; Yoshizumi, Misako; Ueda, Emi; Itoh, Tatsuki; Imano, Motohiro; Satou, Takao; Nishida, Shozo

    2016-07-01

    Interaction between multiple myeloma (MM) cells and the bone marrow microenvironment plays a critical role in MM pathogenesis and the development of drug resistance. Recently, it has been reported that MM cells express the receptor activator of nuclear factor-κB (NF-κB) (RANK). However, the role of the RANK/RANK ligand (RANKL) system in drug resistance remains unclear. In this study, we demonstrated a novel function of the RANK/RANKL system in promoting drug resistance in MM. We found that RANKL treatment induced drug resistance in RANK-expressing but not RANK-negative cell lines. RANKL stimulation of RANK-expressing cells increased multidrug resistance protein 1 (MDR1), breast cancer resistance protein (BCRP), and lung resistance protein 1 (LRP1) expression and decreased Bim expression through various signaling molecules. RNA silencing of Bim expression induced drug resistance, but the RANKL-mediated drug resistance could not be overcome through the RNA silencing of MDR1, BCRP, and LRP1 expression. These results indicate that the RANK/RANKL system induces chemoresistance through the activation of multiple signal transduction pathways and by decreasing Bim expression in RANK-positive MM cells. These findings may prove to be useful in the development of cell adhesion-mediated drug resistance inhibitors in RANK-positive MM cells. PMID:26762414

  20. Toll-Like Receptor (TLR)-1/2 Triggering of Multiple Myeloma Cells Modulates Their Adhesion to Bone Marrow Stromal Cells and Enhances Bortezomib-Induced Apoptosis

    PubMed Central

    Abdi, Jahangir; Mutis, Tuna; Garssen, Johan; Redegeld, Frank A.

    2014-01-01

    In multiple myeloma (MM), the malignant plasma cells usually localize to the bone marrow where they develop drug resistance due to adhesion to stromal cells and various environmental signals. Hence, modulation of this interaction is expected to influence drug sensitivity of MM cells. Toll-like receptor (TLR) ligands have displayed heterogeneous effects on B-cell malignancies and also on MM cells in a few recent studies, but effects on adhesion and drug sensitivity of myeloma cells in the context of bone marrow stromal cells (BMSCs) have never been investigated. In the present study, we explored the modulatory effects of TLR1/2 ligand (Pam3CSK4) on adhesion of human myeloma cells to BMSCs. It is shown that TLR1/2 triggering has opposite effects in different HMCLs on their adhesion to BMSCs. Fravel, L363, UM-6, UM-9 and U266 showed increased adhesion to BMSC in parallel with an increased surface expression of integrin molecules α4 and αVβ3. OPM-1, OPM-2 and NCI-H929 showed a dose-dependent decrease in adhesion upon TLR activation following a downregulation of β7 integrin expression. Importantly, TLR1/2 triggering increased cytotoxic and apoptotic effects of bortezomib in myeloma cells independent of the effect on stromal cell adhesion. Moreover, the apoptosis-enhancing effect of Pam3CSK4 paralleled induction of cleaved caspase-3 protein in FACS analysis suggesting a caspase-dependent mechanism. Our findings uncover a novel role of TLR activation in MM cells in the context of bone marrow microenvironment. Stimulation of TLR1/2 bypasses the protective shield of BMSCs and may be an interesting strategy to enhance drug sensitivity of multiple myeloma cells. PMID:24794258

  1. The multiple myeloma–associated MMSET gene contributes to cellular adhesion, clonogenic growth, and tumorigenicity

    PubMed Central

    Abukhdeir, Abde M.; Konishi, Hiroyuki; Garay, Joseph P.; Gustin, John P.; Wang, Qiuju; Arceci, Robert J.; Matsui, William

    2008-01-01

    Multiple myeloma (MM) is an incurable hematologic malignancy characterized by recurrent chromosomal translocations. Patients with t(4;14)(p16;q32) are the worst prognostic subgroup in MM, although the basis for this poor prognosis is unknown. The t(4;14) is unusual in that it involves 2 potential target genes: fibroblast growth factor receptor 3 (FGFR3) and multiple myeloma SET domain (MMSET). MMSET is universally overexpressed in t(4;14) MM, whereas FGFR3 expression is lost in one-third of cases. Nonetheless, the role of MMSET in t(4;14) MM has remained unclear. Here we demonstrate a role for MMSET in t(4;14) MM cells. Down-regulation of MMSET expression in MM cell lines by RNA interference and by selective disruption of the translocated MMSET allele using gene targeting dramatically reduced colony formation in methylcellulose but had only modest effects in liquid culture. In addition, MMSET knockdown led to cell-cycle arrest of adherent MM cells and reduced the ability of MM cells to adhere to extracellular matrix. Finally, MMSET knockdown and knockout reduced tumor formation by MM xenografts. These results provide the first direct evidence that MMSET plays a significant role in t(4;14) MM and suggest that therapies targeting this gene could impact this particular subset of poor-prognosis patients. PMID:17942756

  2. Junctional adhesion molecule-A is overexpressed in advanced multiple myeloma and determines response to oncolytic reovirus

    PubMed Central

    Kelly, Kevin R.; Espitia, Claudia M.; Zhao, Weiguo; Wendlandt, Erik; Tricot, Guido; Zhan, Fenghuang; Carew, Jennifer S.; Nawrocki, Steffan T.

    2015-01-01

    Despite the development of several new agents for multiple myeloma (MM) therapy over the last decade, drug resistance continues to be a significant problem. Patients with relapsed/refractory disease have high mortality rates and desperately need new precision approaches that directly target specific molecular features that are prevalent in the refractory setting. Reolysin is a proprietary formulation of reovirus for cancer therapy that has demonstrated efficacy in multiple clinical trials. Its selective effects against solid tumors have been largely attributed to RAS-mediated control of reovirus replication. However, the mechanisms regulating its preferential anti-neoplastic effects in MM and other hematological malignancies have not been rigorously studied. Here we report that the reovirus receptor, junctional adhesion molecule-A (JAM-A) is highly expressed in primary cells from patients with MM and the majority of MM cell lines compared to normal controls. A series of experiments demonstrated that JAM-A expression, rather than RAS, was required for Reolysin-induced cell death in MM models. Notably, analysis of paired primary MM specimens revealed that JAM-A expression was significantly increased at relapse compared to diagnosis. Two different models of acquired resistance to bortezomib also displayed both higher JAM-A expression and elevated sensitivity to Reolysin compared to parental cells, suggesting that Reolysin may be an effective agent for patients with relapsed/refractory disease due to their high JAM-A levels. Taken together, these findings support further investigation of Reolysin for the treatment of patients with relapsed/refractory MM and of JAM-A as a predictive biomarker for sensitivity to Reolysin-induced cell death. PMID:26513296

  3. N-Consecutive-Phase Encoder

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Lee, Ho-Kyoung; Weber, Charles

    1995-01-01

    N-consecutive-phase encoder (NCPE) is conceptual encoder for generating alphabet of N consecutive full-response continuous-phase-modulation (CPM) signals. Enables use of binary preencoder of higher rate than used with simple continuous-phase encoder (CPE). NCPE makes possible to achieve power efficiencies and bandwidth efficiencies greater than conventional trellis coders with continuous-phase frequency-shift keying (CPFSK).

  4. Large registry analysis to accurately define second malignancy rates and risks in a well-characterized cohort of 744 consecutive multiple myeloma patients followed-up for 25 years.

    PubMed

    Engelhardt, Monika; Ihorst, Gabriele; Landgren, Ola; Pantic, Milena; Reinhardt, Heike; Waldschmidt, Johannes; May, Annette M; Schumacher, Martin; Kleber, Martina; Wäsch, Ralph

    2015-10-01

    Additional malignancies in multiple myeloma patients after first-line and maintenance treatment have been observed, questioning whether specific risks exist. Second primary malignancies have also gained attention since randomized data showed associations to newer drugs. We have conducted this large registry analysis in 744 consecutive patients and analyzed: 1) frequency and onset of additional malignancies; and 2) second primary malignancy- and myeloma-specific risks. We assessed the frequency of additional malignancies in terms of host-, myeloma- and treatment-specific characteristics. To compare these risks, we estimated cumulative incidence rates for second malignancies and myeloma with Fine and Gray regression models taking into account competing risks. Additional malignancies were found in 118 patients: prior or synchronous malignancies in 63% and subsequent in 37%. Cumulative incidence rates for second malignancies were increased in IgG-myeloma and decreased in bortezomib-treated patients (P<0.05). Cumulative incidence rates for myeloma death were increased with higher stage and age, but decreased in IgG-subtypes and due to anti-myeloma treatment (P<0.05). Cytogenetics in patients acquiring second primary malignancies were predominantly favorable, suggesting that indolent myeloma and long disease latency may allow the manifestation of additional malignancies. An assessment of the Surveillance, Epidemiology, and End Result Program of the National Cancer Institute and our data with long-term follow up of 25 years confirmed a prevalence of second malignancy of 10% at 25 years, whereas death from myeloma decreased from 90% to 83%, respectively. Our important findings widen our knowledge of second malignancies and show that they are of increasing relevance as the prognosis in myeloma improves and mortality rates decrease. PMID:26160877

  5. Large registry analysis to accurately define second malignancy rates and risks in a well-characterized cohort of 744 consecutive multiple myeloma patients followed-up for 25 years

    PubMed Central

    Engelhardt, Monika; Ihorst, Gabriele; Landgren, Ola; Pantic, Milena; Reinhardt, Heike; Waldschmidt, Johannes; May, Annette M.; Schumacher, Martin; Kleber, Martina; Wäsch, Ralph

    2015-01-01

    Additional malignancies in multiple myeloma patients after first-line and maintenance treatment have been observed, questioning whether specific risks exist. Second primary malignancies have also gained attention since randomized data showed associations to newer drugs. We have conducted this large registry analysis in 744 consecutive patients and analyzed: 1) frequency and onset of additional malignancies; and 2) second primary malignancy- and myeloma-specific risks. We assessed the frequency of additional malignancies in terms of host-, myeloma- and treatment-specific characteristics. To compare these risks, we estimated cumulative incidence rates for second malignancies and myeloma with Fine and Gray regression models taking into account competing risks. Additional malignancies were found in 118 patients: prior or synchronous malignancies in 63% and subsequent in 37%. Cumulative incidence rates for second malignancies were increased in IgG-myeloma and decreased in bortezomib-treated patients (P<0.05). Cumulative incidence rates for myeloma death were increased with higher stage and age, but decreased in IgG-subtypes and due to anti-myeloma treatment (P<0.05). Cytogenetics in patients acquiring second primary malignancies were predominantly favorable, suggesting that indolent myeloma and long disease latency may allow the manifestation of additional malignancies. An assessment of the Surveillance, Epidemiology, and End Result Program of the National Cancer Institute and our data with long-term follow up of 25 years confirmed a prevalence of second malignancy of 10% at 25 years, whereas death from myeloma decreased from 90% to 83%, respectively. Our important findings widen our knowledge of second malignancies and show that they are of increasing relevance as the prognosis in myeloma improves and mortality rates decrease. PMID:26160877

  6. Adhesion and migration of avian neural crest cells on fibronectin require the cooperating activities of multiple integrins of the (beta)1 and (beta)3 families.

    PubMed

    Testaz, S; Delannet, M; Duband, J

    1999-12-01

    Based on genetic, functional and histological studies, the extracellular matrix molecule fibronectin has been proposed to play a key role in the migration of neural crest cells in the vertebrate embryo. In the present study, we have analyzed in vitro the repertoire and function of integrin receptors involved in the adhesive and locomotory responses of avian truncal neural crest cells to fibronectin. Immunoprecipitation experiments showed that neural crest cells express multiple integrins, namely (alpha)3(beta)1, (alpha)4(beta)1, (alpha)5(beta)1, (alpha)8(beta)1, (alpha)v(beta)1, (alpha)v(beta)3 and a (beta)8 integrin, as potential fibronectin receptors, and flow cytometry analyses revealed no major heterogeneity among the cell population for expression of integrin subunits. In addition, the integrin repertoire expressed by neural crest cells was found not to change dramatically during migration. At the cellular level, only (alpha)v(beta)1 and (alpha)v(beta)3 were concentrated in focal adhesion sites in connection with the actin microfilaments, whereas the other integrins were predominantly diffuse over the cell surface. In inhibition assays with function-perturbing antibodies, it appeared that complete abolition of cell spreading and migration could be achieved only by blocking multiple integrins of the (beta)1 and (beta)3 families, suggesting possible functional compensations between different integrins. In addition, these studies provided evidence for functional partitioning of integrins in cell adhesion and migration. While spreading was essentially mediated by (alpha)v(beta)1 and (alpha)8(beta)1, migration involved primarily (alpha)4(beta)1, (alpha)v(beta)3 and (alpha)8(beta)1 and, more indirectly, (alpha)3(beta)1. (alpha)5(beta)1 and the (beta)8 integrin were not found to play any major role in either adhesion or migration. Finally, consistent with the results of inhibition experiments, recruitment of (alpha)4(beta)1 and (alpha)v(beta)3, individually or in

  7. Consecutive Measurements in Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Glick, Jennifer R.; Adami, Christoph

    The physics of quantum measurement still continues to puzzle with no resolution in sight between competing interpretations, in particular because no interpretation has so far produced predictions that would be falsifiable via experiment. Here we present an analysis of consecutive projective measurements performed on a quantum state using quantum information theory, where the entanglement between the quantum system and a measuring device is explicitly taken into account, and where the consecutive measurements increase the joint Hilbert space while the wavefunction of the joint system never collapses. Using this relative-state formalism we rederive well-known results for the pairwise correlation between any two measurement devices, but show that considering the joint as well as conditional entropy of three devices reveals a difference between the collapse and no-collapse pictures of quantum measurement that is experimentally testable. This research was funded by a Michigan State University Enrichment Fellowship.

  8. Brain endothelial miR-146a negatively modulates T-cell adhesion through repressing multiple targets to inhibit NF-κB activation.

    PubMed

    Wu, Dongsheng; Cerutti, Camilla; Lopez-Ramirez, Miguel A; Pryce, Gareth; King-Robson, Josh; Simpson, Julie E; van der Pol, Susanne Ma; Hirst, Mark C; de Vries, Helga E; Sharrack, Basil; Baker, David; Male, David K; Michael, Gregory J; Romero, Ignacio A

    2015-03-01

    Pro-inflammatory cytokine-induced activation of nuclear factor, NF-κB has an important role in leukocyte adhesion to, and subsequent migration across, brain endothelial cells (BECs), which is crucial for the development of neuroinflammatory disorders such as multiple sclerosis (MS). In contrast, microRNA-146a (miR-146a) has emerged as an anti-inflammatory molecule by inhibiting NF-κB activity in various cell types, but its effect in BECs during neuroinflammation remains to be evaluated. Here, we show that miR-146a was upregulated in microvessels of MS-active lesions and the spinal cord of mice with experimental autoimmune encephalomyelitis. In vitro, TNFα and IFNγ treatment of human cerebral microvascular endothelial cells (hCMEC/D3) led to upregulation of miR-146a. Brain endothelial overexpression of miR-146a diminished, whereas knockdown of miR-146a augmented cytokine-stimulated adhesion of T cells to hCMEC/D3 cells, nuclear translocation of NF-κB, and expression of adhesion molecules in hCMEC/D3 cells. Furthermore, brain endothelial miR-146a modulates NF-κB activity upon cytokine activation through targeting two novel signaling transducers, RhoA and nuclear factor of activated T cells 5, as well as molecules previously identified, IL-1 receptor-associated kinase 1, and TNF receptor-associated factor 6. We propose brain endothelial miR-146a as an endogenous NF-κB inhibitor in BECs associated with decreased leukocyte adhesion during neuroinflammation. PMID:25515214

  9. Brain endothelial miR-146a negatively modulates T-cell adhesion through repressing multiple targets to inhibit NF-κB activation

    PubMed Central

    Wu, Dongsheng; Cerutti, Camilla; Lopez-Ramirez, Miguel A; Pryce, Gareth; King-Robson, Josh; Simpson, Julie E; van der Pol, Susanne MA; Hirst, Mark C; de Vries, Helga E; Sharrack, Basil; Baker, David; Male, David K; Michael, Gregory J; Romero, Ignacio A

    2015-01-01

    Pro-inflammatory cytokine-induced activation of nuclear factor, NF-κB has an important role in leukocyte adhesion to, and subsequent migration across, brain endothelial cells (BECs), which is crucial for the development of neuroinflammatory disorders such as multiple sclerosis (MS). In contrast, microRNA-146a (miR-146a) has emerged as an anti-inflammatory molecule by inhibiting NF-κB activity in various cell types, but its effect in BECs during neuroinflammation remains to be evaluated. Here, we show that miR-146a was upregulated in microvessels of MS-active lesions and the spinal cord of mice with experimental autoimmune encephalomyelitis. In vitro, TNFα and IFNγ treatment of human cerebral microvascular endothelial cells (hCMEC/D3) led to upregulation of miR-146a. Brain endothelial overexpression of miR-146a diminished, whereas knockdown of miR-146a augmented cytokine-stimulated adhesion of T cells to hCMEC/D3 cells, nuclear translocation of NF-κB, and expression of adhesion molecules in hCMEC/D3 cells. Furthermore, brain endothelial miR-146a modulates NF-κB activity upon cytokine activation through targeting two novel signaling transducers, RhoA and nuclear factor of activated T cells 5, as well as molecules previously identified, IL-1 receptor-associated kinase 1, and TNF receptor-associated factor 6. We propose brain endothelial miR-146a as an endogenous NF-κB inhibitor in BECs associated with decreased leukocyte adhesion during neuroinflammation. PMID:25515214

  10. Application Results and Evaluation of Anti-slip Re-adhesion Control Based on Speed Sensor-less Vector Control and Disturbance Observer for Electric Multiple Units, Series 205-5000

    NASA Astrophysics Data System (ADS)

    Kadowaki, Satoshi; Hata, Tadashi; Hirose, Hiroshi; Ohishi, Kiyoshi; Iida, Norifumi; Takagi, Masashi; Sano, Takashi; Yasukawa, Shinobu

    The improvement of adhesion characteristics is important in electric motor coach. We have already proposed the anti-slip/skid re-adhesion control system based on disturbance observer and sensor-less vector control. The effectiveness of the proposed method has been confirmed by the experiment and the numerical simulation using the tested bogie system of electric motor coach. Then, we apply the proposed method to the actual electric multiple units, which is Series 205-5000. In the experimental results of Series 205-5000, this paper discusses that the proposed anti-slip/skid re-adhesion control system has the desired driving wheel torque response. Moreover, this paper proposes the evaluation method of re-adhesion control test results.

  11. Abdominal Adhesions

    MedlinePlus

    ... Abdominal Adhesions 1 Ward BC, Panitch A. Abdominal adhesions: current and novel therapies. Journal of Surgical Research. 2011;165(1):91– ... are abdominal adhesions and intestinal obstructions ... generally do not require treatment. Surgery is the only way to treat abdominal ...

  12. The effects of cold atmospheric plasma on cell adhesion, differentiation, migration, apoptosis and drug sensitivity of multiple myeloma.

    PubMed

    Xu, Dehui; Luo, Xiaohui; Xu, Yujing; Cui, Qingjie; Yang, Yanjie; Liu, Dingxin; Chen, Hailan; Kong, Michael G

    2016-05-13

    Cold atmospheric plasma was shown to induce cell apoptosis in numerous tumor cells. Recently, some other biological effects, such as induction of membrane permeation and suppression of migration, were discovered by plasma treatment in some types of tumor cells. In this study, we investigated the biological effects of plasma treatment on multiple myeloma cells. We detected the detachment of adherent myeloma cells by plasma, and the detachment area was correlated with higher density of hydroxyl radical in the gas phase of the plasma. Meanwhile, plasma could promote myeloma differentiation by up-regulating Blimp-1 and XBP-1 expression. The migration ability was suppressed by plasma treatment through decreasing of MMP-2 and MMP-9 secretion. In addition, plasma could increase bortezomib sensitivity and induce myeloma cell apoptosis. Taking together, combination with plasma treatment may enhance current chemotherapy and probably improve the outcomes. PMID:27067049

  13. Abdominal Adhesions

    MedlinePlus

    ... Adhesions 1 Ward BC, Panitch A. Abdominal adhesions: current and novel therapies. Journal of Surgical Research. 2011;165(1):91–111. Seek Help for ... and how to participate, visit the NIH Clinical Research Trials and You website ... Foundation for Functional Gastrointestinal Disorders 700 West Virginia ...

  14. Microsurgical lumbar discectomy: preliminary report of 83 consecutive cases.

    PubMed

    Wilson, D H; Kenning, J

    1979-02-01

    The application of microsurgical technique to lumbar discectomy may be of dual value: minimal disruption of the integrity of normal anatomy and meticulous hemostasis may help to speed the process of convalescence, and the retention of epidural fat around the nerve root may help to prevent adhesions, a common cause of the late, "failed disc" syndrome. The authors report their experience with 83 consecutive microdiscectomies for lumbar disc protrusions. The results must be considered as tentative because the follow-up period has been short and the authors found it difficult to quantify the quality of health during the convalescent phase, although this seemed to be excellent. Their short term results are similar to those of the larger series reported by Williams, whose experience with microsurgical lumbar discectomies began 6 years ago. No other series have been reported. The authors describe their technique and compare it to that of Williams. PMID:440544

  15. Differences in expression of junctional adhesion molecule-A and beta-catenin in multiple sclerosis brain tissue: increasing evidence for the role of tight junction pathology.

    PubMed

    Padden, Maureen; Leech, Susie; Craig, Beverly; Kirk, John; Brankin, Brenda; McQuaid, Stephen

    2007-02-01

    Previously we have employed antibodies to the tight junction (TJ)-associated proteins ZO-1 and occludin to describe endothelial tight junction abnormalities, in lesional and normal appearing white matter, in primary and secondary progressive multiple sclerosis (MS). This work is extended here by use of antibodies to the independent TJ-specific proteins and junctional adhesion molecule A & B (JAM-A, JAM-B). We have also assessed the expression in MS of beta-catenin, a protein specific to the TJ-associated adherens junction. Immunocytochemistry and semiquantitative confocal microscopy for JAM-A and beta-catenin was performed on snap-frozen sections from MS cases (n=11) and controls (n=6). Data on 1,443 blood vessels was acquired from active lesions (n=13), inactive lesions (n=13), NAWM (n=20) and control white matter (n=13). In MS abnormal JAM-A expression was found in active (46%) and inactive lesions (21%), comparable to previous data using ZO-1. However, a lower level of TJ abnormality was found in MS NAWM using JAM-A (3%) compared to ZO-1 (13%). JAM-B was strongly expressed on a small number of large blood vessels in control and MS tissues but at too low a level for quantitative analysis. By comparison with the high levels of abnormality observed with the TJ proteins, the adherens junction protein beta-catenin was normally expressed in all MS and control tissue categories. These results confirm, by use of the independent marker JAM-A, that TJ abnormalities are most frequent in active white matter lesions. Altered expression of JAM-A, in addition to affecting junctional tightness may also both reflect and affect leukocyte trafficking, with implications for immune status within the diseased CNS. Conversely, the adherens junction component of the TJ, as indicated by beta-catenin expression is normally expressed in all MS and control tissue categories. PMID:17024496

  16. Polyimide adhesives

    NASA Technical Reports Server (NTRS)

    Progar, D. J.; Bell, V. L.; Saintclair, T. L. (Inventor)

    1974-01-01

    A process of preparing aromatic polyamide-acids for use as adhesives is described. An equimolar quantity of an aromatic dianhydride is added to a stirred solution of an aromatic diamine in a water or alcohol-miscible ether solvent to obtain a viscous polymer solution. The polymeric-acid intermediate polymer does not become insoluble but directly forms a smooth viscous polymer solution. These polyamic-acid polymers are converted, by heating in the range of 200-300 C and with pressure, to form polyimides with excellent adhesive properties.

  17. Cohesion and the Yiddish Consecutive Order.

    ERIC Educational Resources Information Center

    Miner, Kenneth L.

    Literary Yiddish shows a high frequency of declarative sentences with the subject present and the verb in sentence-initial position, the so-called consecutive order. This construction was analyzed in one collection of 17 short narratives and with reference to a hypothesis of German grammarians regarding a similar structure in German. In this…

  18. Plasma polymerization for cell adhesive/anti-adhesive implant coating

    NASA Astrophysics Data System (ADS)

    Meichsner, Juergen; Testrich, Holger; Rebl, Henrike; Nebe, Barbara

    2015-09-01

    Plasma polymerization of ethylenediamine (C2H8N2, EDA) and perfluoropropane (C3F8, PFP) with admixture of argon and hydrogen, respectively, was studied using an asymmetric 13.56 MHz CCP. The analysis of the plasma chemical gas phase processes for stable molecules revealed consecutive reactions: C2H8N2 consumption, intermediate product NH3, and main final product HCN. In C3F8- H2 plasma the precursor molecule C3F8 and molecular hydrogen are consumed and HF as well as CF4 and C2F6 are found as main gaseous reaction products. The deposited plasma polymer films on the powered electrode are strongly cross-linked due to ion bombardment. The stable plasma polymerized films from EDA are characterized by high content of nitrogen with N/C ratio of about 0.35. The plasma polymerized fluorocarbon film exhibit a reduced F/C ratio of about 1.2. Adhesion tests with human osteoblast cell line MG-63 on coated Ti6Al4V samples (polished) compared with uncoated reference sample yielded both, the enhanced cell adhesion for plasma polymerized EDA and significantly reduced cell adhesion for fluorocarbon coating, respectively. Aging of the plasma polymerized EDA film, in particular due to the reactions with oxygen from air, showed no significant change in the cell adhesion. The fluorocarbon coating with low cell adhesion is of interest for temporary implants. Funded by the Campus PlasmaMed.

  19. Consecutive GA Pairs Stabilize Medium Size RNA Internal Loops†

    PubMed Central

    Chen, Gang; Turner, Douglas H.

    2014-01-01

    Internal loops in RNA are important for folding and function. Consecutive non-canonical pairs can form in internal loops having at least two nucleotides on each side. Thermodynamic and structural insights for such internal loops should improve approximations for their stabilities and predictions of secondary and three-dimensional structures. Most natural internal loops are purine rich. A series of oligoribonucleotides that form purine rich internal loops of 5 – 10 nucleotides, including kink-turn loops, were studied by UV melting, exchangeable proton and phosphorus NMR. Three consecutive GA pairs with the motif of 5′YGGA¯3′RAAG or GGA¯R3′AAGY5′ (i.e. 5′GGA¯3′3′AAG5′ closed on at least one side with a CG, UA, or UG pair with Y representing C or U and R representing A or G) stabilize internal loops having six to ten nucleotides. Certain motifs with two consecutive GA pairs are also stabilizing. In internal loops with three or more nucleotides on each side, the motif 5′UG¯3′GA has stability similar to 5′CG¯3′GA. A revised model for predicting stabilities of internal loops with 6 – 10 nucleotides is derived by multiple linear regression. Loops with 2 × 3 nucleotides are predicted well by a previous thermodynamic model. PMID:16548530

  20. Botulinum Toxin A Treatment of Consecutive Esotropia in Children

    PubMed Central

    Couser, Natario L.; Lambert, Scott R.

    2013-01-01

    Objective To assess the outcome of Botulinum A toxin (BTXA) to treat surgically overcorrected intermittent exotropia in children. Methods A retrospective analysis was performed on a series of children with consecutive esotropia treated with BTXA. Results Six children with a mean consecutive esotropia of 21 PD were treated with BTXA at a mean of 19.8 months following strabismus surgery. Two patients underwent a single injection, 3 patients 2 injections, and 1 patient 3 injections. Complications included transient ptosis and a vertical deviation. Mean follow-up from last BTXA injection was 16 months. At last follow-up, 4 of the 6 patients were orthotropic and stereopsis was present in 4 of 5 patients old enough to cooperate with testing. One patient was treated with strabismus surgery following a single BTXA injection. Conclusions BTXA is an efficacious treatment for consecutive esotropia in children. However, in our series, two-thirds of patients required multiple injections to achieve the desired outcome and one ultimately had an additional strabismus surgery. PMID:23211140

  1. RNA interference-mediated knockdown of CD49e (α5 integrin chain) in human thymic epithelial cells modulates the expression of multiple genes and decreases thymocyte adhesion

    PubMed Central

    2010-01-01

    Background The thymus is a central lymphoid organ, in which bone marrow-derived T cell precursors undergo a complex process of maturation. Developing thymocytes interact with thymic microenvironment in a defined spatial order. A component of thymic microenvironment, the thymic epithelial cells, is crucial for the maturation of T-lymphocytes through cell-cell contact, cell matrix interactions and secretory of cytokines/chemokines. There is evidence that extracellular matrix molecules play a fundamental role in guiding differentiating thymocytes in both cortical and medullary regions of the thymic lobules. The interaction between the integrin α5β1 (CD49e/CD29; VLA-5) and fibronectin is relevant for thymocyte adhesion and migration within the thymic tissue. Our previous results have shown that adhesion of thymocytes to cultured TEC line is enhanced in the presence of fibronectin, and can be blocked with anti-VLA-5 antibody. Results Herein, we studied the role of CD49e expressed by the human thymic epithelium. For this purpose we knocked down the CD49e by means of RNA interference. This procedure resulted in the modulation of more than 100 genes, some of them coding for other proteins also involved in adhesion of thymocytes; others related to signaling pathways triggered after integrin activation, or even involved in the control of F-actin stress fiber formation. Functionally, we demonstrated that disruption of VLA-5 in human TEC by CD49e-siRNA-induced gene knockdown decreased the ability of TEC to promote thymocyte adhesion. Such a decrease comprised all CD4/CD8-defined thymocyte subsets. Conclusion Conceptually, our findings unravel the complexity of gene regulation, as regards key genes involved in the heterocellular cell adhesion between developing thymocytes and the major component of the thymic microenvironment, an interaction that is a mandatory event for proper intrathymic T cell differentiation. PMID:21210968

  2. Consecutive plate acoustic suppressor apparatus and methods

    NASA Technical Reports Server (NTRS)

    Doychak, Joseph (Inventor); Parrott, Tony (Inventor)

    1992-01-01

    An apparatus and method for suppressing acoustic noise utilizes consecutive plates, closely spaced to each other so as to exploit dissipation associated with sound propagation in narrow channels to optimize the acoustic resistance at a liner surface. The closely spaced plates can be utilized as high temperature structural materials for jet engines by constructing the plates from composite materials. Geometries of the plates, such as plate depth, shape, thickness, inter-plate spacing, arrangement, etc., can be selected to achieve bulk material-like behavior.

  3. Consecutive Plate Acoustic Suppressor Apparatus and Methods

    NASA Technical Reports Server (NTRS)

    Doychak, Joseph (Inventor); Parrott, Tony L. (Inventor)

    1993-01-01

    An apparatus and method for suppressing acoustic noise utilizes consecutive plates, closely spaced to each other so as to exploit dissipation associated with sound propagation in narrow channels to optimize the acoustic resistance at a liner surface. The closely spaced plates can be utilized as high temperature structural materials for jet engines by constructing the plates from composite materials. Geometries of the plates, such as plate depth, shape, thickness, inter-plate spacing, arrangement, etc., can be selected to achieve bulk material-like behavior.

  4. α2-Macroglobulin Can Crosslink Multiple Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) Molecules and May Facilitate Adhesion of Parasitized Erythrocytes

    PubMed Central

    Stevenson, Liz; Laursen, Erik; Cowan, Graeme J.; Bandoh, Betty; Barfod, Lea; Cavanagh, David R.; Andersen, Gregers R.; Hviid, Lars

    2015-01-01

    Rosetting, the adhesion of Plasmodium falciparum-infected erythrocytes to uninfected erythrocytes, involves clonal variants of the parasite protein P. falciparum erythrocyte membrane protein 1 (PfEMP1) and soluble serum factors. While rosetting is a well-known phenotypic marker of parasites associated with severe malaria, the reason for this association remains unclear, as do the molecular details of the interaction between the infected erythrocyte (IE) and the adhering erythrocytes. Here, we identify for the first time a single serum factor, the abundant serum protease inhibitor α2-macroglobulin (α2M), which is both required and sufficient for rosetting mediated by the PfEMP1 protein HB3VAR06 and some other rosette-mediating PfEMP1 proteins. We map the α2M binding site to the C terminal end of HB3VAR06, and demonstrate that α2M can bind at least four HB3VAR06 proteins, plausibly augmenting their combined avidity for host receptors. IgM has previously been identified as a rosette-facilitating soluble factor that acts in a similar way, but it cannot induce rosetting on its own. This is in contrast to α2M and probably due to the more limited cross-linking potential of IgM. Nevertheless, we show that IgM works synergistically with α2M and markedly lowers the concentration of α2M required for rosetting. Finally, HB3VAR06+ IEs share the capacity to bind α2M with subsets of genotypically distinct P. falciparum isolates forming rosettes in vitro and of patient parasite isolates ex vivo. Together, our results are evidence that P. falciparum parasites exploit α2M (and IgM) to expand the repertoire of host receptors available for PfEMP1-mediated IE adhesion, such as the erythrocyte carbohydrate moieties that lead to formation of rosettes. It is likely that this mechanism also affects IE adhesion to receptors on vascular endothelium. The study opens opportunities for broad-ranging immunological interventions targeting the α2M—(and IgM-) binding domains of PfEMP1

  5. Control of vascular permeability by adhesion molecules.

    PubMed

    Sarelius, Ingrid H; Glading, Angela J

    2015-01-01

    Vascular permeability is a vital function of the circulatory system that is regulated in large part by the limited flux of solutes, water, and cells through the endothelial cell layer. One major pathway through this barrier is via the inter-endothelial junction, which is driven by the regulation of cadherin-based adhesions. The endothelium also forms attachments with surrounding proteins and cells via 2 classes of adhesion molecules, the integrins and IgCAMs. Integrins and IgCAMs propagate activation of multiple downstream signals that potentially impact cadherin adhesion. Here we discuss the known contributions of integrin and IgCAM signaling to the regulation of cadherin adhesion stability, endothelial barrier function, and vascular permeability. Emphasis is placed on known and prospective crosstalk signaling mechanisms between integrins, the IgCAMs- ICAM-1 and PECAM-1, and inter-endothelial cadherin adhesions, as potential strategic signaling nodes for multipartite regulation of cadherin adhesion. PMID:25838987

  6. Spatial interactions between consecutive manual responses.

    PubMed

    Avery, Brittany; Cowper-Smith, Christopher D; Westwood, David A

    2015-11-01

    We have shown that the latency to initiate a reaching movement is increased if its direction is the same as a previous movement compared to movements that differ by 90° or 180° (Cowper-Smith and Westwood in Atten Percept Psychophys 75:1914-1922, 2013). An influential study (Taylor and Klein in J Exp Psychol Hum Percept Perform 26:1639-1656, 2000), however, reported the opposite spatial pattern for manual keypress responses: repeated responses on the same side had reduced reaction time compared to responses on opposite sides. In order to determine whether there are fundamental differences in the patterns of spatial interactions between button-pressing responses and reaching movements, we compared both types of manual responses using common methods. Reaching movements and manual keypress responses were performed in separate blocks of trials using consecutive central arrow stimuli that directed participants to respond to left or right targets. Reaction times were greater for manual responses made to the same target as a previous response (M = 390 ms) as compared to the opposite target (M = 365 ms; similarity main effect: p < 0.001) regardless of whether the response was a reaching movement or a keypress response. This finding is broadly consistent with an inhibitory mechanism operating at the level of motor output that discourages movements that achieve the same spatial goal as a recent action. PMID:26259747

  7. Vernal keratoconjunctivitis in Nigerians: 109 consecutive cases.

    PubMed

    Ukponmwan, Catherine U

    2003-10-01

    Vernal keratoconjunctivitis was the most common conjunctival disease seen over a 2 year period (January 1997-December 1998) at the University of Benin Teaching Hospital, Benin City, Nigeria. One hundred and nine consecutive patients were seen with vernal keratoconjunctivitis. There was a male to female ratio of 1:1.3. The age range of the patients was 5 months to 38 years with a mean age of 15.5 +/- 8.3 years (SD). Of the patients 54.1% were children. Itching was the most common symptom, followed by redness, tearing, aching eye and photophobia. Ninety patients (82.6%) had predominantly tarsal papillae, while the others had mixed and limbal papillae. A history of atopic diseases such as asthma and rhinitis was present in only five patients (4.5%). There was no patient with corneal ulcer or scarring. Although the complications were few, health education of the patients about the dangers of self medication with steroids should be emphasized. PMID:14620434

  8. Sundew adhesive: a naturally occurring hydrogel

    PubMed Central

    Huang, Yujian; Wang, Yongzhong; Sun, Leming; Agrawal, Richa; Zhang, Mingjun

    2015-01-01

    Bioadhesives have drawn increasing interest in recent years, owing to their eco-friendly, biocompatible and biodegradable nature. As a typical bioadhesive, sticky exudate observed on the stalked glands of sundew plants aids in the capture of insects and this viscoelastic adhesive has triggered extensive interests in revealing the implied adhesion mechanisms. Despite the significant progress that has been made, the structural traits of the sundew adhesive, especially the morphological characteristics in nanoscale, which may give rise to the viscous and elastic properties of this mucilage, remain unclear. Here, we show that the sundew adhesive is a naturally occurring hydrogel, consisting of nano-network architectures assembled with polysaccharides. The assembly process of the polysaccharides in this hydrogel is proposed to be driven by electrostatic interactions mediated with divalent cations. Negatively charged nanoparticles, with an average diameter of 231.9 ± 14.8 nm, are also obtained from this hydrogel and these nanoparticles are presumed to exert vital roles in the assembly of the nano-networks. Further characterization via atomic force microscopy indicates that the stretching deformation of the sundew adhesive is associated with the flexibility of its fibrous architectures. It is also observed that the adhesion strength of the sundew adhesive is susceptible to low temperatures. Both elasticity and adhesion strength of the sundew adhesive reduce in response to lowering the ambient temperature. The feasibility of applying sundew adhesive for tissue engineering is subsequently explored in this study. Results show that the fibrous scaffolds obtained from sundew adhesive are capable of increasing the adhesion of multiple types of cells, including fibroblast cells and smooth muscle cells, a property that results from the enhanced adsorption of serum proteins. In addition, in light of the weak cytotoxic activity exhibited by these scaffolds towards a variety of

  9. Sundew adhesive: a naturally occurring hydrogel.

    PubMed

    Huang, Yujian; Wang, Yongzhong; Sun, Leming; Agrawal, Richa; Zhang, Mingjun

    2015-06-01

    Bioadhesives have drawn increasing interest in recent years, owing to their eco-friendly, biocompatible and biodegradable nature. As a typical bioadhesive, sticky exudate observed on the stalked glands of sundew plants aids in the capture of insects and this viscoelastic adhesive has triggered extensive interests in revealing the implied adhesion mechanisms. Despite the significant progress that has been made, the structural traits of the sundew adhesive, especially the morphological characteristics in nanoscale, which may give rise to the viscous and elastic properties of this mucilage, remain unclear. Here, we show that the sundew adhesive is a naturally occurring hydrogel, consisting of nano-network architectures assembled with polysaccharides. The assembly process of the polysaccharides in this hydrogel is proposed to be driven by electrostatic interactions mediated with divalent cations. Negatively charged nanoparticles, with an average diameter of 231.9 ± 14.8 nm, are also obtained from this hydrogel and these nanoparticles are presumed to exert vital roles in the assembly of the nano-networks. Further characterization via atomic force microscopy indicates that the stretching deformation of the sundew adhesive is associated with the flexibility of its fibrous architectures. It is also observed that the adhesion strength of the sundew adhesive is susceptible to low temperatures. Both elasticity and adhesion strength of the sundew adhesive reduce in response to lowering the ambient temperature. The feasibility of applying sundew adhesive for tissue engineering is subsequently explored in this study. Results show that the fibrous scaffolds obtained from sundew adhesive are capable of increasing the adhesion of multiple types of cells, including fibroblast cells and smooth muscle cells, a property that results from the enhanced adsorption of serum proteins. In addition, in light of the weak cytotoxic activity exhibited by these scaffolds towards a variety of

  10. Thermal Characterization of Adhesive

    NASA Technical Reports Server (NTRS)

    Spomer, Ken A.

    1999-01-01

    The current Space Shuttle Reusable Solid Rocket Motor (RSRM) nozzle adhesive bond system is being replaced due to obsolescence. Down-selection and performance testing of the structural adhesives resulted in the selection of two candidate replacement adhesives, Resin Technology Group's Tiga 321 and 3M's EC2615XLW. This paper describes rocket motor testing of these two adhesives. Four forty-pound charge motors were fabricated in configurations that would allow side by side comparison testing of the candidate replacement adhesives and the current RSRM adhesives. The motors provided an environment where the thermal performance of adhesives in flame surface bondlines was compared. Results of the FPC testing show that: 1) The phenolic char depths on radial bond lines is approximately the same and vary depending on the position in the blast tube regardless of which adhesive was used; 2) The adhesive char depth of the candidate replacement adhesives is less than the char depth of the current adhesives; 3) The heat-affected depth of the candidate replacement adhesives is less than the heat-affected depth of the current adhesives; and 4) The ablation rates for both replacement adhesives are slower than that of the current adhesives.

  11. Human climbing with efficiently scaled gecko-inspired dry adhesives

    PubMed Central

    Hawkes, Elliot W.; Eason, Eric V.; Christensen, David L.; Cutkosky, Mark R.

    2015-01-01

    Since the discovery of the mechanism of adhesion in geckos, many synthetic dry adhesives have been developed with desirable gecko-like properties such as reusability, directionality, self-cleaning ability, rough surface adhesion and high adhesive stress. However, fully exploiting these adhesives in practical applications at different length scales requires efficient scaling (i.e. with little loss in adhesion as area grows). Just as natural gecko adhesives have been used as a benchmark for synthetic materials, so can gecko adhesion systems provide a baseline for scaling efficiency. In the tokay gecko (Gekko gecko), a scaling power law has been reported relating the maximum shear stress σmax to the area A: σmax ∝ A−1/4. We present a mechanical concept which improves upon the gecko's non-uniform load-sharing and results in a nearly even load distribution over multiple patches of gecko-inspired adhesive. We created a synthetic adhesion system incorporating this concept which shows efficient scaling across four orders of magnitude of area, yielding an improved scaling power law: σmax ∝ A−1/50. Furthermore, we found that the synthetic adhesion system does not fail catastrophically when a simulated failure is induced on a portion of the adhesive. In a practical demonstration, the synthetic adhesion system enabled a 70 kg human to climb vertical glass with 140 cm2 of adhesive per hand. PMID:25411404

  12. Understanding Marine Mussel Adhesion

    SciTech Connect

    H. G. Silverman; F. F. Roberto

    2007-12-01

    In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are waterimpervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion.

  13. Understanding Marine Mussel Adhesion

    PubMed Central

    Roberto, Francisco F.

    2007-01-01

    In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are water-impervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion. PMID:17990038

  14. Understanding marine mussel adhesion.

    PubMed

    Silverman, Heather G; Roberto, Francisco F

    2007-01-01

    In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are water-impervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion. PMID:17990038

  15. Rapid Reversible Photoswitching of Integrin-Mediated Adhesion at the Single-Cell Level.

    PubMed

    Kadem, Laith F; Holz, Michelle; Suana, Kristine Grace; Li, Qian; Lamprecht, Constanze; Herges, Rainer; Selhuber-Unkel, Christine

    2016-03-01

    Rapid and reversible photoswitching of cell adhesion is achieved by c(RGDfK)-azobenzenes embedded in a poly(ethylene glycol) background on surfaces. The light-induced cis-trans-isomerization of the azobenzene enables switching of cell adhesion on the surface. Reversibility of switching over several consecutive switching cycles is demonstrated by single-cell force spectroscopy. PMID:26685922

  16. Pathophysiology and prevention of postoperative peritoneal adhesions

    PubMed Central

    Arung, Willy; Meurisse, Michel; Detry, Olivier

    2011-01-01

    Peritoneal adhesions represent an important clinical challenge in gastrointestinal surgery. Peritoneal adhesions are a consequence of peritoneal irritation by infection or surgical trauma, and may be considered as the pathological part of healing following any peritoneal injury, particularly due to abdominal surgery. The balance between fibrin deposition and degradation is critical in determining normal peritoneal healing or adhesion formation. Postoperative peritoneal adhesions are a major cause of morbidity resulting in multiple complications, many of which may manifest several years after the initial surgical procedure. In addition to acute small bowel obstruction, peritoneal adhesions may cause pelvic or abdominal pain, and infertility. In this paper, the authors reviewed the epidemiology, pathogenesis and various prevention strategies of adhesion formation, using Medline and PubMed search. Several preventive agents against postoperative peritoneal adhesions have been investigated. Their role aims in activating fibrinolysis, hampering coagulation, diminishing the inflammatory response, inhibiting collagen synthesis or creating a barrier between adjacent wound surfaces. Their results are encouraging but most of them are contradictory and achieved mostly in animal model. Until additional findings from future clinical researches, only a meticulous surgery can be recommended to reduce unnecessary morbidity and mortality rates from these untoward effects of surgery. In the current state of knowledge, pre-clinical or clinical studies are still necessary to evaluate the effectiveness of the several proposed prevention strategies of postoperative peritoneal adhesions. PMID:22147959

  17. Quantitation of Endothelial Cell Adhesiveness In Vitro

    PubMed Central

    Lowe, Donna J.; Raj, Kenneth

    2015-01-01

    One of the cardinal processes of inflammation is the infiltration of immune cells from the lumen of the blood vessel to the surrounding tissue. This occurs when endothelial cells, which line blood vessels, become adhesive to circulating immune cells such as monocytes. In vitro measurement of this adhesiveness has until now been done by quantifying the total number of monocytes that adhere to an endothelial layer either as a direct count or by indirect measurement of the fluorescence of adherent monocytes. While such measurements do indicate the average adhesiveness of the endothelial cell population, they are confounded by a number of factors, such as cell number, and do not reveal the proportion of endothelial cells that are actually adhesive. Here we describe and demonstrate a method which allows the enumeration of adhesive cells within a tested population of endothelial monolayer. Endothelial cells are grown on glass coverslips and following desired treatment are challenged with monocytes (that may be fluorescently labeled). After incubation, a rinsing procedure, involving multiple rounds of immersion and draining, the cells are fixed. Adhesive endothelial cells, which are surrounded by monocytes are readily identified and enumerated, giving an adhesion index that reveals the actual proportion of endothelial cells within the population that are adhesive. PMID:26132714

  18. PH dependent adhesive peptides

    DOEpatents

    Tomich, John; Iwamoto, Takeo; Shen, Xinchun; Sun, Xiuzhi Susan

    2010-06-29

    A novel peptide adhesive motif is described that requires no receptor or cross-links to achieve maximal adhesive strength. Several peptides with different degrees of adhesive strength have been designed and synthesized using solid phase chemistries. All peptides contain a common hydrophobic core sequence flanked by positively or negatively charged amino acids sequences.

  19. Ins and Outs of Microbial Adhesion

    NASA Astrophysics Data System (ADS)

    Virji, Mumtaz

    Microbial adhesion is generally a complex process, involving multiple adhesins on a single microbe and their respective target receptors on host cells. In some situations, various adhesins of a microbe may co-operate in an apparently hierarchical and sequential manner whereby the first adhesive event triggers the target cell to express receptors for additional microbial adhesins. In other instances, adhesins may act in concert leading to high avidity interactions, often a prelude to cellular invasion and tissue penetration. Mechanisms used to target the host include both lectin-like interactions and protein-protein interactions; the latter are often highly specific for the host or a tissue within the host. This reflective chapter aims to offer a point of view on microbial adhesion by presenting some experiences and thoughts especially related to respiratory pathogens and explore if there can be any future hope of controlling bacterial infections via preventing adhesion or invasion stages of microbial pathogenesis.

  20. Reversible Thermoset Adhesives

    NASA Technical Reports Server (NTRS)

    Mac Murray, Benjamin C. (Inventor); Tong, Tat H. (Inventor); Hreha, Richard D. (Inventor)

    2016-01-01

    Embodiments of a reversible thermoset adhesive formed by incorporating thermally-reversible cross-linking units and a method for making the reversible thermoset adhesive are provided. One approach to formulating reversible thermoset adhesives includes incorporating dienes, such as furans, and dienophiles, such as maleimides, into a polymer network as reversible covalent cross-links using Diels Alder cross-link formation between the diene and dienophile. The chemical components may be selected based on their compatibility with adhesive chemistry as well as their ability to undergo controlled, reversible cross-linking chemistry.

  1. Adhesion at metal interfaces

    NASA Technical Reports Server (NTRS)

    Banerjea, Amitava; Ferrante, John; Smith, John R.

    1991-01-01

    A basic adhesion process is defined, the theory of the properties influencing metallic adhesion is outlined, and theoretical approaches to the interface problem are presented, with emphasis on first-principle calculations as well as jellium-model calculations. The computation of the energies of adhesion as a function of the interfacial separation is performed; fully three-dimensional calculations are presented, and universality in the shapes of the binding energy curves is considered. An embedded-atom method and equivalent-crystal theory are covered in the framework of issues involved in practical adhesion.

  2. Postoperative Peritoneal Adhesions

    PubMed Central

    Ryan, Graeme B.; Grobéty, Jocelyne; Majno, Guido

    1971-01-01

    This paper describes an experimental model of peritoneal adhesions, in the rat, based on two relatively minor accidents that may occur during abdominal surgery in man: drying of the serosa, and bleeding. Drying alone had little effect; drying plus bleeding consistently produced adhesions to the dried area. Fresh blood alone produced adhesions between the three membranous structures [omentum and pelvic fat bodies (PFBs)]. The formation of persistent adhesions required whole blood. Preformed clots above a critical size induced adhesions even without previous serosal injury; they were usually captured by the omentum and PFBs. If all three membranous structures were excised, the clots caused visceral adhesions. The protective role of the omentum, its structure, and the mechanism of omental adhesions, are discussed. These findings are relevant to the pathogenesis of post-operative adhesions in man. ImagesFig 3Fig 4Fig 5Fig 6Fig 7Fig 12Fig 13Fig 1Fig 2Fig 14Fig 15Fig 8Fig 9Fig 10Fig 11 PMID:5315369

  3. Polymer nanocarriers for dentin adhesion.

    PubMed

    Osorio, R; Osorio, E; Medina-Castillo, A L; Toledano, M

    2014-12-01

    To obtain more durable adhesion to dentin, and to protect collagen fibrils of the dentin matrix from degradation, calcium- and phosphate-releasing particles have been incorporated into the dental adhesive procedure. The aim of the present study was to incorporate zinc-loaded polymeric nanocarriers into a dental adhesive system to facilitate inhibition of matrix metalloproteinases (MMPs)-mediated collagen degradation and to provide calcium ions for mineral deposition within the resin-dentin bonded interface. PolymP- N : Active nanoparticles (nanoMyP) were zinc-loaded through 30-minute ZnCl2 immersion and tested for bioactivity by means of 7 days' immersion in simulated body fluid solution (the Kokubo test). Zinc-loading and calcium phosphate depositions were examined by scanning and transmission electron microscopy, elemental analysis, and x-ray diffraction. Nanoparticles in ethanol solution infiltrated into phosphoric-acid-etched human dentin and Single Bond (3M/ESPE) were applied to determine whether the nanoparticles interfered with bonding. Debonded sticks were analyzed by scanning electron microscopy. A metalloproteinase collagen degradation assay was also performed in resin-infiltrated dentin with and without nanoparticles, measuring C-terminal telopeptide of type I collagen (ICTP) concentration in supernatants, after 4 wk of immersion in artificial saliva. Numerical data were analyzed by analysis of variance (ANOVA) and Student-Newman-Keuls multiple comparisons tests (p < .05). Nanoparticles were effectively zinc-loaded and were shown to have a chelating effect, retaining calcium regardless of zinc incorporation. Nanoparticles failed to infiltrate demineralized intertubular dentin and remained on top of the hybrid layer, without altering bond strength. Calcium and phosphorus were found covering nanoparticles at the hybrid layer, after 24 h. Nanoparticle application in etched dentin also reduced MMP-mediated collagen degradation. Tested nanoparticles may be

  4. Polymer Nanocarriers for Dentin Adhesion

    PubMed Central

    Osorio, R.; Osorio, E.; Medina-Castillo, A.L.; Toledano, M.

    2014-01-01

    To obtain more durable adhesion to dentin, and to protect collagen fibrils of the dentin matrix from degradation, calcium- and phosphate-releasing particles have been incorporated into the dental adhesive procedure. The aim of the present study was to incorporate zinc-loaded polymeric nanocarriers into a dental adhesive system to facilitate inhibition of matrix metalloproteinases (MMPs)-mediated collagen degradation and to provide calcium ions for mineral deposition within the resin-dentin bonded interface. PolymP-nActive nanoparticles (nanoMyP) were zinc-loaded through 30-minute ZnCl2 immersion and tested for bioactivity by means of 7 days’ immersion in simulated body fluid solution (the Kokubo test). Zinc-loading and calcium phosphate depositions were examined by scanning and transmission electron microscopy, elemental analysis, and x-ray diffraction. Nanoparticles in ethanol solution infiltrated into phosphoric-acid-etched human dentin and Single Bond (3M/ESPE) were applied to determine whether the nanoparticles interfered with bonding. Debonded sticks were analyzed by scanning electron microscopy. A metalloproteinase collagen degradation assay was also performed in resin-infiltrated dentin with and without nanoparticles, measuring C-terminal telopeptide of type I collagen (ICTP) concentration in supernatants, after 4 wk of immersion in artificial saliva. Numerical data were analyzed by analysis of variance (ANOVA) and Student-Newman-Keuls multiple comparisons tests (p < .05). Nanoparticles were effectively zinc-loaded and were shown to have a chelating effect, retaining calcium regardless of zinc incorporation. Nanoparticles failed to infiltrate demineralized intertubular dentin and remained on top of the hybrid layer, without altering bond strength. Calcium and phosphorus were found covering nanoparticles at the hybrid layer, after 24 h. Nanoparticle application in etched dentin also reduced MMP-mediated collagen degradation. Tested nanoparticles may be

  5. Approaching improved adhesive bonding repeatability

    NASA Astrophysics Data System (ADS)

    Schlette, Christian; Müller, Tobias; Roβmann, Jürgen; Brecher, Christian

    2016-03-01

    Today, the precision of micro-optics assembly is mostly limited by the accuracy of the bonding process ― and in the case of adhesive bonding by the prediction and compensation of adhesive shrinkage during curing. In this contribution, we present a novel approach to address adhesive bonding based on hybrid control system theory. In hybrid control, dynamic systems are described as "plants" which produce discrete and/or continuous outputs from given discrete and/or continuous inputs, thus yielding a hybrid state space description of the system. The task of hybrid controllers is to observe the plant and to generate a discrete and/or continuous input sequence that guides or holds the plant in a desired target state region while avoiding invalid or unwanted intermediate states. Our approach is based on a series of experiments carried out in order to analyze, define and decouple the dependencies of adhesive shrinkage on multiple parameters, such as application geometries, fixture forces and UV intensities. As some of the dependencies describe continuous effects (e.g. shrinkage from UV intensity) and other dependencies describe discrete state transitions (e.g. fixture removal during curing), the resulting model of the overall bonding process is a hybrid dynamic system in the general case. For this plant model, we then propose a concept of sampling-based parameter search as a basis to design suitable hybrid controllers, which have the potential to optimize process control for a selection of assembly steps, thus improving the repeatability of related production steps like beam-shaping optics or mounting of turning mirrors for fiber coupling.

  6. Yielding Elastic Tethers Stabilize Robust Cell Adhesion

    PubMed Central

    Whitfield, Matt J.; Luo, Jonathon P.; Thomas, Wendy E.

    2014-01-01

    Many bacteria and eukaryotic cells express adhesive proteins at the end of tethers that elongate reversibly at constant or near constant force, which we refer to as yielding elasticity. Here we address the function of yielding elastic adhesive tethers with Escherichia coli bacteria as a model for cell adhesion, using a combination of experiments and simulations. The adhesive bond kinetics and tether elasticity was modeled in the simulations with realistic biophysical models that were fit to new and previously published single molecule force spectroscopy data. The simulations were validated by comparison to experiments measuring the adhesive behavior of E. coli in flowing fluid. Analysis of the simulations demonstrated that yielding elasticity is required for the bacteria to remain bound in high and variable flow conditions, because it allows the force to be distributed evenly between multiple bonds. In contrast, strain-hardening and linear elastic tethers concentrate force on the most vulnerable bonds, which leads to failure of the entire adhesive contact. Load distribution is especially important to noncovalent receptor-ligand bonds, because they become exponentially shorter lived at higher force above a critical force, even if they form catch bonds. The advantage of yielding is likely to extend to any blood cells or pathogens adhering in flow, or to any situation where bonds are stretched unequally due to surface roughness, unequal native bond lengths, or conditions that act to unzip the bonds. PMID:25473833

  7. Cytotoxicity of denture adhesives.

    PubMed

    de Gomes, Pedro Sousa; Figueiral, Maria Helena; Fernandes, Maria Helena R; Scully, Crispian

    2011-12-01

    Ten commercially available denture adhesives, nine soluble formulations (six creams, three powders) and one insoluble product (pad), were analyzed regarding the cytotoxicity profile in direct and indirect assays using L929 fibroblast cells. In the direct assay, fibroblasts were seeded over the surface of a thick adhesive gel (5%, creams; 2.5%, powders and pad). In the indirect assay, cells were cultured in the presence of adhesive extracts prepared in static and dynamic conditions (0.5-2%, creams; 0.25-1%, powders and pad). Cell toxicity was assessed for cell viability/proliferation (MTT assay) and cell morphology (observation of the F-actin cytoskeleton organization by confocal laser scanning microscopy). Direct contact of the L929 fibroblasts with the thick adhesive gels caused no, or only a slight, decrease in cell viability/proliferation. The adhesive extracts (especially those prepared in dynamic conditions) caused significantly higher growth inhibition of fibroblasts and, in addition, caused dose- and time-dependent effects, throughout the 6-72 h exposure time. Also, dose-dependent effects on cell morphology, with evident disruption of the F-actin cytoskeleton organization, were seen in the presence of most adhesives. In conclusion, the adhesives possessed different degrees of cytotoxicity, but similar dose- and time-dependent biological profiles. PMID:20844908

  8. Cell adhesion force microscopy

    PubMed Central

    Sagvolden, G.; Giaever, I.; Pettersen, E. O.; Feder, J.

    1999-01-01

    The adhesion forces of cervical carcinoma cells in tissue culture were measured by using the manipulation force microscope, a novel atomic force microscope. The forces were studied as a function of time and temperature for cells cultured on hydrophilic and hydrophobic polystyrene substrates with preadsorbed proteins. The cells attached faster and stronger at 37°C than at 23°C and better on hydrophilic than on hydrophobic substrates, even though proteins adsorb much better to the hydrophobic substrates. Because cell adhesion serves to control several stages in the cell cycle, we anticipate that the manipulation force microscope can help clarify some cell-adhesion related issues. PMID:9892657

  9. Adhesive Contact Sweeper

    NASA Technical Reports Server (NTRS)

    Patterson, Jonathan D.

    1993-01-01

    Adhesive contact sweeper removes hair and particles vacuum cleaner leaves behind, without stirring up dust. Also cleans loose rugs. Sweeper holds commercially available spools of inverted adhesive tape. Suitable for use in environments in which air kept free of dust; optics laboratories, computer rooms, and areas inhabited by people allergic to dust. For carpets, best used in tandem with vacuum cleaner; first pass with vacuum cleaner removes coarse particles, and second pass with sweeper extracts fine particles. This practice extends useful life of adhesive spools.

  10. Focal adhesions in osteoneogenesis

    PubMed Central

    Biggs, M.J.P; Dalby, M.J

    2010-01-01

    As materials technology and the field of tissue engineering advances, the role of cellular adhesive mechanisms, in particular the interactions with implantable devices, becomes more relevant in both research and clinical practice. A key tenet of medical device technology is to use the exquisite ability of biological systems to respond to the material surface or chemical stimuli in order to help develop next-generation biomaterials. The focus of this review is on recent studies and developments concerning focal adhesion formation in osteoneogenesis, with an emphasis on the influence of synthetic constructs on integrin mediated cellular adhesion and function. PMID:21287830

  11. Consecutive parthenogenetic births in a spotted eagle ray Aetobatus narinari.

    PubMed

    Harmon, T S; Kamerman, T Y; Corwin, A L; Sellas, A B

    2016-02-01

    Genetic evidence is given to support consecutive parthenogenesis in a spotted eagle ray Aetobatus narinari using nuclear microsatellite genotyping. To date, only a handful of births involving the parthenogenesis process in chondrichthyans have been verified using microsatellite markers and even fewer verified as recurring births. This appears to be the first documented case of this process occurring in a myliobatid species. PMID:26563982

  12. Confabulations after bilateral consecutive strokes of the lenticulostriate arteries.

    PubMed

    Carota, Antonio; Calabrese, Pasquale

    2012-01-01

    We describe the case of a 75-year-old woman who manifested persistent confabulations after two consecutive strokes encompassing the area of the lenticulostriate arteries territory on both hemispheres. Findings reported on this rare clinical syndrome suggest that fantastic confabulations and delusional thoughts may arise after bilateral damage of subcortical nonthalamic structures. PMID:22649343

  13. Confabulations after Bilateral Consecutive Strokes of the Lenticulostriate Arteries

    PubMed Central

    Carota, Antonio; Calabrese, Pasquale

    2012-01-01

    We describe the case of a 75-year-old woman who manifested persistent confabulations after two consecutive strokes encompassing the area of the lenticulostriate arteries territory on both hemispheres. Findings reported on this rare clinical syndrome suggest that fantastic confabulations and delusional thoughts may arise after bilateral damage of subcortical nonthalamic structures. PMID:22649343

  14. Exploring the Sums of Powers of Consecutive q-Integers

    ERIC Educational Resources Information Center

    Kim, T.; Ryoo, C. S.; Jang, L. C.; Rim, S. H.

    2005-01-01

    The Bernoulli numbers are among the most interesting and important number sequences in mathematics. They first appeared in the posthumous work "Ars Conjectandi" (1713) by Jacob Bernoulli (1654-1705) in connection with sums of powers of consecutive integers (Bernoulli, 1713; or Smith, 1959). Bernoulli numbers are particularly important in number…

  15. TOPICAL REVIEW: Recent advances in the fabrication and adhesion testing of biomimetic dry adhesives

    NASA Astrophysics Data System (ADS)

    Sameoto, D.; Menon, C.

    2010-10-01

    In the past two years, there have been a large number of publications on the topic of biomimetic dry adhesives from modeling, fabrication and testing perspectives. We review and compare the most recent advances in fabrication and testing of these materials. While there is increased convergence and consensus as to what makes a good dry adhesive, the fabrication of these materials is still challenging, particularly for anisotropic or hierarchal designs. Although qualitative comparisons between different adhesive designs can be made, quantifying the exact performance and rating each design is significantly hampered by the lack of standardized testing methods. Manufacturing dry adhesives, which can reliably adhere to rough surfaces, show directional and self-cleaning behavior and are relatively simple to manufacture, is still very challenging—great strides by multiple research groups have however made these goals appear achievable within the next few years.

  16. Adhesion of Lunar Dust

    NASA Astrophysics Data System (ADS)

    Walton, Otis R.

    2007-04-01

    This paper reviews the physical characteristics of lunar dust and the effects of various fundamental forces acting on dust particles on surfaces in a lunar environment. There are transport forces and adhesion forces after contact. Mechanical forces (i.e., from rover wheels, astronaut boots and rocket engine blast) and static electric effects (from UV photo-ionization and/or tribo-electric charging) are likely to be the major contributors to the transport of dust particles. If fine regolith particles are deposited on a surface, then surface energy-related (e.g., van der Walls) adhesion forces and static-electric-image forces are likely to be the strongest contributors to adhesion. Some measurement techniques are offered to quantify the strength of adhesion forces. And finally some dust removal techniques are discussed.

  17. Adhesion of Lunar Dust

    NASA Technical Reports Server (NTRS)

    Walton, Otis R.

    2007-01-01

    This paper reviews the physical characteristics of lunar dust and the effects of various fundamental forces acting on dust particles on surfaces in a lunar environment. There are transport forces and adhesion forces after contact. Mechanical forces (i.e., from rover wheels, astronaut boots and rocket engine blast) and static electric effects (from UV photo-ionization and/or tribo-electric charging) are likely to be the major contributors to the transport of dust particles. If fine regolith particles are deposited on a surface, then surface energy-related (e.g., van der Walls) adhesion forces and static-electric-image forces are likely to be the strongest contributors to adhesion. Some measurement techniques are offered to quantify the strength of adhesion forces. And finally some dust removal techniques are discussed.

  18. Optical adhesive property study

    SciTech Connect

    Sundvold, P.D.

    1996-01-01

    Tests were performed to characterize the mechanical and thermal properties of selected optical adhesives to identify the most likely candidate which could survive the operating environment of the Direct Optical Initiation (DOI) program. The DOI system consists of a high power laser and an optical module used to split the beam into a number of channels to initiate the system. The DOI requirements are for a high shock environment which current military optical systems do not operate. Five candidate adhesives were selected and evaluated using standardized test methods to determine the adhesives` physical properties. EC2216, manufactured by 3M, was selected as the baseline candidate adhesive based on the test results of the physical properties.

  19. Adhesives for Aerospace

    NASA Technical Reports Server (NTRS)

    Meade, L. E.

    1985-01-01

    The industry is hereby challenged to integrate adhesive technology with the total structure requirements in light of today's drive into automation/mechanization. The state of the art of adhesive technology is fairly well meeting the needs of the structural designers, the processing engineer, and the inspector, each on an individual basis. The total integration of these needs into the factory of the future is the next collective hurdle to be achieved. Improved processing parameters to fit the needs of automation/mechanization will necessitate some changes in the adhesive forms, formulations, and chemistries. Adhesives have, for the most part, kept up with the needs of the aerospace industry, normally leading the rest of the industry in developments. The wants of the aerospace industry still present a challenge to encompass all elements, achieving a totally integrated joined and sealed structural system. Better toughness with hot-wet strength improvements is desired. Lower cure temperatures, longer out times, and improved corrosion inhibition are desired.

  20. Leucocyte cellular adhesion molecules.

    PubMed

    Yong, K; Khwaja, A

    1990-12-01

    Leucocytes express adhesion promoting receptors which mediate cell-cell and cell-matrix interactions. These adhesive interactions are crucial to the regulation of haemopoiesis and thymocyte maturation, the direction and control of leucocyte traffic and migration through tissues, and in the development of immune and non-immune inflammatory responses. Several families of adhesion receptors have been identified (Table). The leucocyte integrin family comprises 3 alpha beta heterodimeric membrane glycoproteins which share a common beta subunit, designated CD18. The alpha subunits of each of the 3 members, lymphocyte function associated antigen-1 (LFA-1), macrophage antigen-1 (Mac-1) and p150,95 are designated CD11a, b and c respectively. These adhesion molecules play a critical part in the immune and inflammatory responses of leucocytes. The leucocyte integrin family is, in turn, part of the integrin superfamily, members of which are evolutionally, structurally and functionally related. Another Integrin subfamily found on leucocytes is the VLA group, so-called because the 'very late activation antigens' VLA-1 and VLA-2 were originally found to appear late in T-cell activation. Members of this family function mainly as extracellular matrix adhesion receptors and are found both on haemopoietic and non-haemopoietic cells. They play a part in diverse cellular functions including tissue organisation, lymphocyte recirculation and T-cell immune responses. A third integrin subfamily, the cytoadhesins, are receptors on platelets and endothelial cells which bind extracellular matrix proteins. A second family of adhesion receptors is the immunoglobulin superfamily, members of which include CD2, LFA-3 and ICAM-1, which participate in T-cell adhesive interactions, and the antigen-specific receptors of T and B cells, CD4, CD8 and the MHC Class I and II molecules. A recently recognised family of adhesion receptors is the selectins, characterised by a common lectin domain. Leucocyte

  1. High temperature adhesives

    NASA Technical Reports Server (NTRS)

    St.clair, Terry L.

    1991-01-01

    The aerospace and electronics industries have an ever increasing need for higher performance materials. In recent years, linear aromatic polyimides have been proven to be a superior class of materials for various applications in these industries. The use of this class of polymers as adhesives is continuing to increase. Several NASA Langley developed polyimides show considerable promise as adhesives because of their high glass transition temperatures, thermal stability, resistance to solvents/water, and their potential for cost effective manufacture.

  2. Maximal charge injection of consecutive electron pulses with uniform temporal pulse separation

    SciTech Connect

    Liu, Y. L.; Zhang, P.; Chen, S. H.; Ang, L. K.

    2015-08-15

    A charge sheet model is proposed for the study of the space-charge limited density of consecutive electron pulses injected to in a diode with uniform temporal pulse separation. Based on the model, an analytical formula is derived for expressing the dependency of the charge density limit on the gap spacing, gap voltage, and pulse separation. The theoretical results are verified by numerical solutions up to electron energy of a few MeV, including relativistic effects. The model can be applied to the design of multiple-pulse electron beams for time resolved electron microscopy and free electron lasers.

  3. Laparoscopic Management of Adhesive Small Bowel Obstruction

    PubMed Central

    Konjic, Ferid; Idrizovic, Enes; Hasukic, Ismar; Jahic, Alen

    2016-01-01

    Introduction: Adhesions are the reason for bowel obstruction in 80% of the cases. In well selected patients the adhesive ileus laparoscopic treatment has multiple advantages which include the shorter hospitalization period, earlier food taking, and less postoperative morbidity rate. Case report: Here we have a patient in the age of 35 hospitalized at the clinic due to occlusive symptoms. Two years before an opened appendectomy had been performed on him. He underwent the treatment of exploration laparoscopy and laparoscopic adhesiolysis. Dilated small bowel loops connected with the anterior abdominal wall in the ileocecal region by adhesions were found intraoperatively and then resected harmonically with scalpel. One strangulation around which a small bowel loop was wrapped around was found and dissected. Postoperative course was normal. PMID:27041815

  4. Physical outcome in a successful Italian Serie A soccer team over three consecutive seasons.

    PubMed

    Vigne, Gregory; Dellal, Alexandre; Gaudino, Claudio; Chamari, Karim; Rogowski, Isabelle; Alloatti, Guisseppe; Wong, P Del; Owen, Adam; Hautier, Christophe

    2013-05-01

    The aim of this study was to examine the physical performance of a successful Italian Serie A team of more than 3 consecutive seasons. Twenty-five players participated in the study and were classified into 3 playing positions: defenders (n = 9), midfielders (n = 11), and forwards (n = 5). Activities match were studied by an analysis of multiple match camera SICS throughout the competition Italian Serie A matches played at home (n = 90) for 3 consecutive seasons (first: 2004/2005; second: 2005/2006; and third: 2006/2007). Total team ball possession and time-motion characteristics were examined. Results showed that total ball possession (52.1-54.9%) and the number of points accumulated at home (40/48) improved in the past 3 seasons, whereas the final rankings at home were stable. The total distances covered by minutes of play were significantly different between the 3 seasons (118.32 ± 6.69 m·min to 111.96 ± 8.05 m·min). Distance running and high-intensity activities were similar in the 3 seasons, whereas the distance covered in moderate-intensity running decreased in the third (p < 0.05). Variations between playing positions were found during the 3 consecutive seasons, with midfielders covering greater distances than defenders (p < 0.05) and forwards (p < 0.01). This study showed how for 3 consecutive seasons a Serie A team of successful players reduced their distances performed at submaximal speeds, and increased ball possession, while maintaining the high-intensity activities and the number of points at home. It is suggested that this is because of a better understanding of roles and tactics team organization and to act collectively and individually on these parameters to reduce energy expenditure during the game to maintain a high-level performance throughout the season. PMID:22820208

  5. Controllable ON-OFF adhesion for Earth orbit grappling applications

    NASA Astrophysics Data System (ADS)

    Parness, Aaron; Hilgendorf, Tyler; Daniel, Phillip; Frost, Matt; White, Victor; Kennedy, Brett

    ON-OFF adhesives can benefit multiple Earth orbit applications by providing the capability to selectively anchor two surfaces together repeatedly and releasably without significant preload. Key to this new capability, targets will not need special preparation; ON-OFF adhesives can be used with cooperative and non-cooperative objects, like defunct satellites or space debris. Using an ON-OFF adhesive gripper allows large surfaces on a target to serve as potential grapple points, reducing the precision needed in the sensing and control throughout the grapple operation. A space-rated adhesive structure is presented that can be turned ON-OFF using a slight sliding motion. This adhesive mimics the geometry and performance characteristics of the adhesive structures found on the feet of gecko lizards. Results from adhesive testing on common orbital surfaces like solar panels, thermal blankets, composites, and painted surfaces are presented. Early environmental testing results from cold temperature and vacuum tests are also presented. Finally, the paper presents the design, fabrication, and preliminary testing of a gripping mechanism enabled by these ON-OFF adhesives in preparation for satellite-servicing applications. Adhesive levels range from near zero on rough surfaces to more than 75 kPa on smooth surfaces like glass.

  6. Unexpected biases in the distribution of consecutive primes.

    PubMed

    Lemke Oliver, Robert J; Soundararajan, Kannan

    2016-08-01

    Although the sequence of primes is very well distributed in the reduced residue classes [Formula: see text], the distribution of pairs of consecutive primes among the permissible ϕ(q)(2) pairs of reduced residue classes [Formula: see text] is surprisingly erratic. This paper proposes a conjectural explanation for this phenomenon, based on the Hardy-Littlewood conjectures. The conjectures are then compared with numerical data, and the observed fit is very good. PMID:27418603

  7. Sorted consecutive local binary pattern for texture classification.

    PubMed

    Ryu, Jongbin; Hong, Sungeun; Yang, Hyun S

    2015-07-01

    In this paper, we propose a sorted consecutive local binary pattern (scLBP) for texture classification. Conventional methods encode only patterns whose spatial transitions are not more than two, whereas scLBP encodes patterns regardless of their spatial transition. Conventional methods do not encode patterns on account of rotation-invariant encoding; on the other hand, patterns with more than two spatial transitions have discriminative power. The proposed scLBP encodes all patterns with any number of spatial transitions while maintaining their rotation-invariant nature by sorting the consecutive patterns. In addition, we introduce dictionary learning of scLBP based on kd-tree which separates data with a space partitioning strategy. Since the elements of sorted consecutive patterns lie in different space, it can be generated to a discriminative code with kd-tree. Finally, we present a framework in which scLBPs and the kd-tree can be combined and utilized. The results of experimental evaluation on five texture data sets--Outex, CUReT, UIUC, UMD, and KTH-TIPS2-a--indicate that our proposed framework achieves the best classification rate on the CUReT, UMD, and KTH-TIPS2-a data sets compared with conventional methods. The results additionally indicate that only a marginal difference exists between the best classification rate of conventional methods and that of the proposed framework on the UIUC and Outex data sets. PMID:25850088

  8. Epithelial Cell Adhesion Molecule

    PubMed Central

    Trzpis, Monika; McLaughlin, Pamela M.J.; de Leij, Lou M.F.H.; Harmsen, Martin C.

    2007-01-01

    The epithelial cell adhesion molecule (EpCAM, CD326) is a glycoprotein of ∼40 kd that was originally identified as a marker for carcinoma, attributable to its high expression on rapidly proliferating tumors of epithelial origin. Normal epithelia express EpCAM at a variable but generally lower level than carcinoma cells. In early studies, EpCAM was proposed to be a cell-cell adhesion molecule. However, recent insights revealed a more versatile role for EpCAM that is not limited only to cell adhesion but includes diverse processes such as signaling, cell migration, proliferation, and differentiation. Cell surface expression of EpCAM may actually prevent cell-cell adhesion. Here, we provide a comprehensive review of the current knowledge on EpCAM biology in relation to other cell adhesion molecules. We discuss the implications of the newly identified functions of EpCAM in view of its prognostic relevance in carcinoma, inflammatory pathophysiology, and tissue development and regeneration as well as its role in normal epithelial homeostasis. PMID:17600130

  9. Flexibilized copolyimide adhesives

    NASA Technical Reports Server (NTRS)

    Progar, Donald J.; St.clair, Terry L.

    1988-01-01

    Two copolyimides, LARC-STPI and STPI-LARC-2, with flexible backbones were processed and characterized as adhesives. The processability and adhesive properties were compared to those of a commercially available form of LARC-TPI. Lap shear specimens were fabricated using adhesive tape prepared from each of the three polymers. Lap shear tests were performed at room temperature, 177 C, and 204 C before and after exposure to water-boil and to thermal aging at 204 C for up to 1000 hours. The three adhesive systems possess exceptional lap shear strengths at room temperature and elevated temperatures both before and after thermal exposure. LARC-STPI, because of its high glass transition temperature provided high lap shear strengths up to 260 C. After water-boil, LARC-TPI exhibited the highest lap shear strengths at room temperature and 177 C, whereas the LARC-STPI retained a higher percentage of its original strength when tested at 204 C. These flexible thermoplastic copolyimides show considerable potential as adhesives based on this study and because of the ease of preparation with low cost, commercially available materials.

  10. Platelet Adhesion under Flow

    PubMed Central

    Ruggeri, Zaverio M.

    2011-01-01

    Platelet adhesive mechanisms play a well-defined role in hemostasis and thrombosis, but evidence continues to emerge for a relevant contribution to other pathophysiological processes including inflammation, immune-mediated responses to microbial and viral pathogens, and cancer metastasis. Hemostasis and thrombosis are related aspects of the response to vascular injury, but the former protects from bleeding after trauma while the latter is a disease mechanism. In either situation, adhesive interactions mediated by specific membrane receptors support the initial attachment of single platelets to cellular and extracellular matrix constituents of the vessel wall and tissues. In the subsequent steps of thrombus growth and stabilization, adhesive interactions mediate platelet to platelet cohesion (aggregation) and anchoring to the fibrin clot. A key functional aspect of platelets is their ability to circulate in a quiescent state surveying the integrity of the inner vascular surface, coupled to a prompt reaction wherever alterations are detected. In many respects, therefore, platelet adhesion to vascular wall structures, to one another or to other blood cells are facets of the same fundamental biological process. The adaptation of platelet adhesive functions to the effects of blood flow is the main focus of this review. PMID:19191170

  11. Protein mediated membrane adhesion

    NASA Astrophysics Data System (ADS)

    Carlson, Andreas; Mahadevan, L.

    2015-05-01

    Adhesion in the context of mechanical attachment, signaling, and movement in cellular dynamics is mediated by the kinetic interactions between membrane-embedded proteins in an aqueous environment. Here, we present a minimal theoretical framework for the dynamics of membrane adhesion that accounts for the kinetics of protein binding, the elastic deformation of the membrane, and the hydrodynamics of squeeze flow in the membrane gap. We analyze the resulting equations using scaling estimates to characterize the spatiotemporal features of the adhesive patterning and corroborate them using numerical simulations. In addition to characterizing aspects of cellular dynamics, our results might also be applicable to a range of phenomena in physical chemistry and materials science where flow, deformation, and kinetics are coupled to each other in slender geometries.

  12. Adhesive particle shielding

    DOEpatents

    Klebanoff, Leonard Elliott; Rader, Daniel John; Walton, Christopher; Folta, James

    2009-01-06

    An efficient device for capturing fast moving particles has an adhesive particle shield that includes (i) a mounting panel and (ii) a film that is attached to the mounting panel wherein the outer surface of the film has an adhesive coating disposed thereon to capture particles contacting the outer surface. The shield can be employed to maintain a substantially particle free environment such as in photolithographic systems having critical surfaces, such as wafers, masks, and optics and in the tools used to make these components, that are sensitive to particle contamination. The shield can be portable to be positioned in hard-to-reach areas of a photolithography machine. The adhesive particle shield can incorporate cooling means to attract particles via the thermophoresis effect.

  13. Natural Underwater Adhesives

    PubMed Central

    Stewart, Russell J.; Ransom, Todd C.; Hlady, Vladimir

    2011-01-01

    The general topic of this review is protein-based underwater adhesives produced by aquatic organisms. The focus is on mechanisms of interfacial adhesion to native surfaces and controlled underwater solidification of natural water-borne adhesives. Four genera that exemplify the broad range of function, general mechanistic features, and unique adaptations are discussed in detail: blue mussels, acorn barnacles, sandcastle worms, and freshwater caddisfly larva. Aquatic surfaces in nature are charged and in equilibrium with their environment, populated by an electrical double layer of ions as well as adsorbed natural polyelectrolytes and microbial biofilms. Surface adsorption of underwater bioadhesives likely occurs by exchange of surface bound ligands by amino acid sidechains, driven primarily by relative affinities and effective concentrations of polymeric functional groups. Most aquatic organisms exploit modified amino acid sidechains, in particular phosphorylated serines and hydroxylated tyrosines (dopa), with high-surface affinity that form coordinative surface complexes. After delivery to the surfaces as a fluid, permanent natural adhesives solidify to bear sustained loads. Mussel plaques are assembled in a manner superficially reminiscent of in vitro layer-by-layer strategies, with sequentially delivered layers associated through Fe(dopa)3 coordination bonds. The adhesives of sandcastle worms, caddisfly larva, and barnacles may be delivered in a form somewhat similar to in vitro complex coacervation. Marine adhesives are secreted, or excreted, into seawater that has a significantly higher pH and ionic strength than the internal environment. Empirical evidence suggests these environment triggers could provide minimalistic, fail-safe timing mechanisms to prevent premature solidification (insolubilization) of the glue within the secretory system, yet allow rapid solidification after secretion. Underwater bioadhesives are further strengthened by secondary covalent

  14. A Continuum Approach to Modelling Cell-Cell Adhesion

    PubMed Central

    Armstrong, Nicola J.; Painter, Kevin J.; Sherratt, Jonathan A.

    2007-01-01

    Cells adhere to each other through the binding of cell adhesion molecules at the cell surface. This process, known as cell-cell adhesion, is fundamental in many areas of biology, including early embryo development, tissue homeostasis and tumour growth. In this paper we develop a new continuous mathematical model of this phenomenon by considering the movement of cells in response to the adhesive forces generated through binding. We demonstrate that our model predicts the aggregation behaviour of a disassociated adhesive cell population. Further, when the model is extended to represent the interactions between multiple populations, we demonstrate that it is capable of replicating the different types of cell sorting behaviour observed experimentally. The resulting pattern formation is a direct consequence of the relative strengths of self-population and cross-population adhesive bonds in the model. While cell sorting behaviour has been captured previously with discrete approaches, it has not, until now, been observed with a fully continuous model. PMID:16860344

  15. Timer cover adhesive optimization

    SciTech Connect

    Carleton, J.J. II.

    1992-03-17

    The implementation of PROCODE as the data acquisition system for processing timers has required some modifications to the method of identifying timer assemblies. PROCODE requires machine-readable labelling of the assemblies. This report describes a series of experiments to find an adhesive that would keep labels attached to timers regardless of the condition of their surface when the label was applied and regardless of the heat, vibration, and shock they endured afterwards. The effect of the variation of these experimental factors on the performance of the adhesive was determined by using a Taguchi experimental design.

  16. Metallic Adhesion and Bonding

    NASA Technical Reports Server (NTRS)

    Ferrante, J.; Smith, J. R.; Rose, J. H.

    1984-01-01

    Although metallic adhesion has played a central part in much tribological speculation, few quantitative theoretical calculations are available. This is in part because of the difficulties involved in such calculations and in part because the theoretical physics community is not particularly involved with tribology. The calculations currently involved in metallic adhesion are summarized and shown that these can be generalized into a scaled universal relationship. Relationships exist to other types of covalent bonding, such as cohesive, chemisorptive, and molecular bonding. A simple relationship between surface energy and cohesive energy is offered.

  17. Elastomer toughened polyimide adhesives

    NASA Technical Reports Server (NTRS)

    St.clair, A. K.; St.clair, T. L. (Inventor)

    1983-01-01

    A rubber-toughened addition-type polyimide composition is disclosed which has excellent high temperature bonding characteristics in the fully cured state, and improved peel strength and adhesive fracture resistance physical property characteristics. The process for making the improved adhesive involves preparing the rubber containing amic acid prepolymer by chemically reacting an amine-terminated elastomer and an aromatic diamine with an aromatic dianhydride with which a reactive chain stopper anhydride was mixed, and utilizing solvent or mixture of solvents for the reaction.

  18. Switchable bio-inspired adhesives

    NASA Astrophysics Data System (ADS)

    Kroner, Elmar

    2015-03-01

    Geckos have astonishing climbing abilities. They can adhere to almost any surface and can run on walls and even stick to ceilings. The extraordinary adhesion performance is caused by a combination of a complex surface pattern on their toes and the biomechanics of its movement. These biological dry adhesives have been intensely investigated during recent years because of the unique combination of adhesive properties. They provide high adhesion, allow for easy detachment, can be removed residue-free, and have self-cleaning properties. Many aspects have been successfully mimicked, leading to artificial, bio-inspired, patterned dry adhesives, and were addressed and in some aspects they even outperform the adhesion capabilities of geckos. However, designing artificial patterned adhesion systems with switchable adhesion remains a big challenge; the gecko's adhesion system is based on a complex hierarchical surface structure and on advanced biomechanics, which are both difficult to mimic. In this paper, two approaches are presented to achieve switchable adhesion. The first approach is based on a patterned polydimethylsiloxane (PDMS) polymer, where adhesion can be switched on and off by applying a low and a high compressive preload. The switch in adhesion is caused by a reversible mechanical instability of the adhesive silicone structures. The second approach is based on a composite material consisting of a Nickel- Titanium (NiTi) shape memory alloy and a patterned adhesive PDMS layer. The NiTi alloy is trained to change its surface topography as a function of temperature, which results in a change of the contact area and of alignment of the adhesive pattern towards a substrate, leading to switchable adhesion. These examples show that the unique properties of bio-inspired adhesives can be greatly improved by new concepts such as mechanical instability or by the use of active materials which react to external stimuli.

  19. Consecutive polarizers arrangement producing maximum polarized light intensity

    NASA Astrophysics Data System (ADS)

    Wirjawan, Johannes V. D.

    2016-03-01

    Polarizer mainly functions as a specific filter that blocks or transmits lights of certain polarization. Malus' law predicts the average intensity of polarized light passing a polarizer that transmits certain polarization direction will be proportional to the squared cosine of angle between the two polarization directions. Arranging several polarizers consecutively with various transmission directions will produce various final intensity as well as final polarized direction. Specific arrangement of an arbitrary number (N > 3) of polarizers producing maximum intensity of polarized light will be discussed in this paper. In addition, interesting pattern of maximum values of some trigonometric functions that are difficult to be solved analytically can be obtained from this discussion.

  20. Switchable Adhesion in Vacuum Using Bio-Inspired Dry Adhesives.

    PubMed

    Purtov, Julia; Frensemeier, Mareike; Kroner, Elmar

    2015-11-01

    Suction based attachment systems for pick and place handling of fragile objects like glass plates or optical lenses are energy-consuming and noisy and fail at reduced air pressure, which is essential, e.g., in chemical and physical vapor deposition processes. Recently, an alternative approach toward reversible adhesion of sensitive objects based on bioinspired dry adhesive structures has emerged. There, the switching in adhesion is achieved by a reversible buckling of adhesive pillar structures. In this study, we demonstrate that these adhesives are capable of switching adhesion not only in ambient air conditions but also in vacuum. Our bioinspired patterned adhesive with an area of 1 cm(2) provided an adhesion force of 2.6 N ± 0.2 N in air, which was reduced to 1.9 N ± 0.2 N if measured in vacuum. Detachment was induced by buckling of the structures due to a high compressive preload and occurred, independent of air pressure, at approximately 0.9 N ± 0.1 N. The switch in adhesion was observed at a compressive preload between 5.6 and 6.0 N and was independent of air pressure. The difference between maximum adhesion force and adhesion force after buckling gives a reasonable window of operation for pick and place processes. High reversibility of the switching behavior is shown over 50 cycles in air and in vacuum, making the bioinspired switchable adhesive applicable for handling operations of fragile objects. PMID:26457864

  1. Switchable Adhesion in Vacuum Using Bio-Inspired Dry Adhesives

    PubMed Central

    2015-01-01

    Suction based attachment systems for pick and place handling of fragile objects like glass plates or optical lenses are energy-consuming and noisy and fail at reduced air pressure, which is essential, e.g., in chemical and physical vapor deposition processes. Recently, an alternative approach toward reversible adhesion of sensitive objects based on bioinspired dry adhesive structures has emerged. There, the switching in adhesion is achieved by a reversible buckling of adhesive pillar structures. In this study, we demonstrate that these adhesives are capable of switching adhesion not only in ambient air conditions but also in vacuum. Our bioinspired patterned adhesive with an area of 1 cm2 provided an adhesion force of 2.6 N ± 0.2 N in air, which was reduced to 1.9 N ± 0.2 N if measured in vacuum. Detachment was induced by buckling of the structures due to a high compressive preload and occurred, independent of air pressure, at approximately 0.9 N ± 0.1 N. The switch in adhesion was observed at a compressive preload between 5.6 and 6.0 N and was independent of air pressure. The difference between maximum adhesion force and adhesion force after buckling gives a reasonable window of operation for pick and place processes. High reversibility of the switching behavior is shown over 50 cycles in air and in vacuum, making the bioinspired switchable adhesive applicable for handling operations of fragile objects. PMID:26457864

  2. Adept Adhesion Reduction Solution

    MedlinePlus

    ... icodextrin. The fluid is used during or after laparoscopic gynecological surgery to separate and protect tissues and decrease the number of new adhesions after surgery. Adept® is supplied sterile, in a single-use bag. How does it work? During surgery, ...

  3. Adhesion molecules and receptors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adhesion molecules are necessary for leukocyte trafficking and differentiation. They serve to initiate cell-cell interactions under conditions of shear, and they sustain the cell-cell and cell-matrix interactions needed for cellular locomotion. They also can serve directly as signaling molecules act...

  4. Wood Composite Adhesives

    NASA Astrophysics Data System (ADS)

    Gomez-Bueso, Jose; Haupt, Robert

    The global environment, in which phenolic resins are being used for wood composite manufacture, has changed significantly during the last decade. This chapter reviews trends that are driving the use and consumption of phenolic resins around the world. The review begins with recent data on volume usage and regional trends, followed by an analysis of factors affecting global markets. In a section on environmental factors, the impact of recent formaldehyde emission regulations is discussed. The section on economics introduces wood composite production as it relates to the available adhesive systems, with special emphasis on the technical requirement to improve phenolic reactivity. Advances in composite process technology are introduced, especially in regard to the increased demands the improvements place upon adhesive system performance. The specific requirements for the various wood composite families are considered in the context of adhesive performance needs. The results of research into current chemistries are discussed, with a review of recent findings regarding the mechanisms of phenolic condensation and acceleration. Also, the work regarding alternate natural materials, such as carbohydrates, lignins, tannins, and proteinaceous materials, is presented. Finally, new developments in alternative adhesive technologies are reported.

  5. Rapid adhesive bonding concepts

    NASA Technical Reports Server (NTRS)

    Stein, B. A.; Tyeryar, J. R.; Hodges, W. T.

    1984-01-01

    Adhesive bonding in the aerospace industry typically utilizes autoclaves or presses which have considerable thermal mass. As a consequence, the rates of heatup and cooldown of the bonded parts are limited and the total time and cost of the bonding process is often relatively high. Many of the adhesives themselves do not inherently require long processing times. Bonding could be performed rapidly if the heat was concentrated in the bond lines or at least in the adherends. Rapid adhesive bonding concepts were developed to utilize induction heating techniques to provide heat directly to the bond line and/or adherends without heating the entire structure, supports, and fixtures of a bonding assembly. Bonding times for specimens are cut by a factor of 10 to 100 compared to standard press bonding. The development of rapid adhesive bonding for lap shear specimens (per ASTM D1003 and D3163), for aerospace panel bonding, and for field repair needs of metallic and advanced fiber reinforced polymeric matrix composite structures are reviewed.

  6. Adhesion testing of aircraft tires

    NASA Technical Reports Server (NTRS)

    Bobo, S. N.

    1983-01-01

    Adhesion testing appeared to offer a less burdensome alternative to replace some of the dynamometer tests. Accordingly, test results and data were requested from retreaders who had used adhesion testing.

  7. Resistance heating releases structural adhesive

    NASA Technical Reports Server (NTRS)

    Glemser, N. N.

    1967-01-01

    Composite adhesive package bonds components together for testing and enables separation when testing is completed. The composite of adhesives, insulation and a heating element separate easily when an electrical current is applied.

  8. 3-D foam adhesive deposition

    NASA Technical Reports Server (NTRS)

    Lemons, C. R.; Salmassy, O. K.

    1976-01-01

    Bonding method, which reduces amount and weight of adhesive, is applicable to foam-filled honeycomb constructions. Novel features of process include temperature-viscosity control and removal of excess adhesive by transfer to cellophane film.

  9. Scaling Reversible Adhesion in Synthetic and Biological Systems

    NASA Astrophysics Data System (ADS)

    Bartlett, Michael; Irschick, Duncan; Crosby, Alfred

    2013-03-01

    High capacity, easy release polymer adhesives, as demonstrated by a gecko's toe, present unique opportunities for synthetic design. However, without a framework that connects biological and synthetic adhesives from basic nanoscopic features to macroscopic systems, synthetic mimics have failed to perform favorably at large length scales. Starting from an energy balance, we develop a scaling approach to understand unstable interfacial fracture over multiple length scales. The simple theory reveals that reversibly adhesive polymers do not rely upon fibrillar features but require contradicting attributes: maximum compliance normal to the substrate and minimum compliance in the loading direction. We use this counterintuitive criterion to create reversible, easy release adhesives at macroscopic sizes (100 cm2) with unprecedented force capacities on the order of 3000 N. Importantly, we achieve this without fibrillar features, supporting our predictions and emphasizing the importance of subsurface anatomy in biological adhesive systems. Our theory describes adhesive force capacity as a function of material properties and geometry and is supported by over 1000 experiments, spanning both synthetic and biological adhesives, with agreement over 14 orders of magnitude in adhesive force.

  10. Analysis of the surface effects on adhesion in MEMS structures

    NASA Astrophysics Data System (ADS)

    Rusu, F.; Pustan, M.; Bîrleanu, C.; Müller, R.; Voicu, R.; Baracu, A.

    2015-12-01

    One of the main failure causes in microelectromechanical systems (MEMS) is stiction. Stiction is the adhesion of contacting surfaces due to surface forces. Adhesion force depends on the operating conditions and is influenced by the contact area. In this study, the adhesion force between MEMS materials and the AFM tips is analyzed using the spectroscopy in point mode of the AFM. The aim is to predict the stiction failure mode in MEMS. The investigated MEMS materials are silicon, polysilicon, platinum, aluminum, and gold. Three types of investigations were conducted. The first one aimed to determine the variation of the adhesion force with respect to the variation of the roughness. The roughness has a strong influence on the adhesion because the contact area between components increases if the roughness decreases. The second type of investigation aimed to determine the adhesion force in multiple points of each considered sample. The values obtained experimentally for the adhesion force were also validated using the JKR and DMT models. The third type of investigation was conducted with the purpose of determining the influence of the temperature on the adhesion force.

  11. Coating Reduces Ice Adhesion

    NASA Technical Reports Server (NTRS)

    Smith, Trent; Prince, Michael; DwWeese, Charles; Curtis, Leslie

    2008-01-01

    The Shuttle Ice Liberation Coating (SILC) has been developed to reduce the adhesion of ice to surfaces on the space shuttle. SILC, when coated on a surface (foam, metal, epoxy primer, polymer surfaces), will reduce the adhesion of ice by as much as 90 percent as compared to the corresponding uncoated surface. This innovation is a durable coating that can withstand several cycles of ice growth and removal without loss of anti-adhesion properties. SILC is made of a binder composed of varying weight percents of siloxane(s), ethyl alcohol, ethyl sulfate, isopropyl alcohol, and of fine-particle polytetrafluoroethylene (PTFE). The combination of these components produces a coating with significantly improved weathering characteristics over the siloxane system alone. In some cases, the coating will delay ice formation and can reduce the amount of ice formed. SILC is not an ice prevention coating, but the very high water contact angle (greater than 140 ) causes water to readily run off the surface. This coating was designed for use at temperatures near -170 F (-112 C). Ice adhesion tests performed at temperatures from -170 to 20 F (-112 to -7 C) show that SILC is a very effective ice release coating. SILC can be left as applied (opaque) or buffed off until the surface appears clear. Energy dispersive spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS) data show that the coating is still present after buffing to transparency. This means SILC can be used to prevent ice adhesion even when coating windows or other objects, or items that require transmission of optical light. Car windshields are kept cleaner and SILC effectively mitigates rain and snow under driving conditions.

  12. Relationship between consecutive deterioration of mean deviation value and progression of visual field defect in open-angle glaucoma

    PubMed Central

    Naito, Tomoko; Yoshikawa, Keiji; Mizoue, Shiro; Nanno, Mami; Kimura, Tairo; Suzumura, Hirotaka; Takeda, Ryuji; Shiraga, Fumio

    2015-01-01

    Purpose To analyze the relationship between consecutive deterioration of mean deviation (MD) value and glaucomatous visual field (VF) progression in open-angle glaucoma (OAG), including primary OAG and normal tension glaucoma. Patients and methods The subjects of the study were patients undergoing treatment for OAG who had performed VF tests at least 10 times with a Humphrey field analyzer (SITA standard, C30-2 program). The VF progression was defined by a significantly negative MD slope (MD slope worsening) at the final VF test during the follow-up period. The relationship between the MD slope worsening and the consecutive deterioration of MD value were retrospectively analyzed. Results A total of 165 eyes of 165 patients were included in the analysis. Significant progression of VF defects was observed in 72 eyes of 72 patients (43.6%), while no significant progression was evident in 93 eyes of 93 patients (56.4%). There was significant relationship between the frequency of consecutive deterioration of MD value and MD slope worsening (P<0.0001, Cochran–Armitage trend test). A significant association was observed for MD slope worsening in the eyes with three (odds ratio: 2.1, P=0.0224) and four (odds ratio: 3.6, P=0.0008) consecutive deterioration of MD value in multiple logistic regression analysis, but no significant association in the eyes with two consecutive deterioration (odds ratio: 1.1, P=0.8282). The eyes with VF progression had significantly lower intraocular pressure reduction rate (P<0.01). Conclusion This retrospective study has shown that three or more consecutive deterioration of MD value might be a predictor to future significant MD slope worsening in OAG. PMID:26648689

  13. Focal Adhesion Kinase-Dependent Regulation of Adhesive Force Involves Vinculin Recruitment to Focal Adhesions

    PubMed Central

    Hanks, Steven K.; García, Andrés J.

    2016-01-01

    Background information Focal adhesion kinase (FAK), an essential non-receptor tyrosine kinase, plays pivotal roles in migratory responses, adhesive signaling, and mechanotransduction. FAK-dependent regulation of cell migration involves focal adhesion turnover dynamics as well as actin cytoskeleton polymerization and lamellipodia protrusion. Whereas roles for FAK in migratory and mechanosensing responses have been established, the contributions of FAK to the generation of adhesive forces are not well understood. Results Using FAK-null cells expressing wild-type and mutant FAK under an inducible tetracycline promoter, we analyzed the role of FAK in the generation of steady-state adhesive forces using micropatterned substrates and a hydrodynamic adhesion assay. FAK expression reduced steady-state strength by 30% compared to FAK-null cells. FAK expression reduced vinculin localization to focal adhesions by 35% independently from changes in integrin binding and localization of talin and paxillin. RNAi knockdown of vinculin abrogated the FAK-dependent differences in adhesive force. FAK-dependent changes in vinculin localization and adhesive force were confirmed in human primary fibroblasts with FAK knocked down by RNAi. The autophosphorylation Y397 and kinase domain Y576/Y577 sites were differentially required for FAK-mediated adhesive responses. Conclusions We demonstrate that FAK reduces steady-state adhesion strength by modulating vinculin recruitment to focal adhesions. These findings provide insights into the role of FAK in mechanical interactions between a cell and the extracellular matrix. PMID:19883375

  14. Three consecutive pregnancies in a patient with glycogen storage disease type IA (von Gierke's disease).

    PubMed

    Ryan, I P; Havel, R J; Laros, R K

    1994-06-01

    Glycogen storage disease type IA is associated with metabolic abnormalities that can compromise fetal outcome. Normal outcome can be achieved by maintaining euglycemia throughout gestation. We report three consecutive pregnancies in a patient with glycogen storage disease type IA. The patient, a 35-year-old woman, has been maintained on a regimen of nightly nasogastric or cornstarch feedings for the past 12 years with improving metabolic control, reduced liver size, and no progression of multiple hepatic adenomas. On confirmation of each pregnancy, early in the first trimester nightly feeding was changed from cornstarch ingestion to Polycose by nasogastric intubation, with good metabolic control. During the last trimester of each pregnancy metabolic control showed further improvement, with lowering of lactate, urate, and triglyceride levels. During the first pregnancy unexpected fetal death occurred at 33 weeks. During the last two pregnancies, the patient was admitted at 33 and 34 weeks, respectively, for closer supervision of metabolic status and fetal monitoring. She underwent a cesarean section at 35 weeks 4 days of gestation and was delivered of a girl. She underwent a repeat cesarean section at 35 weeks 2 days for the subsequent gestation and was delivered of a boy. Both infants are healthy and appear to be unaffected by von Gierke's disease. Hepatic adenomas did not enlarge during the pregnancies. Meticulous management resulted in normal pregnancy outcomes in two consecutive gestations. Rapid fetal growth late in the third trimester may require particularly careful supervision to maintain euglycemia. PMID:8203427

  15. Vegetarianism in anorexia nervosa? A review of 116 consecutive cases.

    PubMed

    O'Connor, M A; Touyz, S W; Dunn, S M; Beumont, P J

    A retrospective study was carried out of 116 consecutive patients with anorexia nervosa to ascertain the extent and nature of vegetarianism in this population. Sixty-three (54.3%) patients were found to be avoiding red meat. In only four (6.3%) of these did meat avoidance predate the onset of their anorexia nervosa. Of the remaining 59 patients (best termed pseudovegetarians), 25 (42.4%) patients continued to avoid red meat by the end of treatment. Pseudovegetarianism was associated with a longer duration of anorexia nervosa, a lower weight during the course of their illness, and living away from the parental home. The reintroduction of red meat into the diet was more likely if vegetarianism were of a short duration. PMID:3696039

  16. Consecutive laparoscopic gallbladder and spleen resections in cirrhotic patients

    PubMed Central

    Wang, Ming-Jun; Li, Jun-Li; Zhou, Jin; Wu, Zhong; Peng, Bing

    2014-01-01

    AIM: To evaluate the feasibility, safety, and effectiveness of consecutive laparoscopic cholecystectomy (LC) plus splenectomy (LS) in liver cirrhosis patients. METHODS: From 2003 to 2013, 17 (group 1) patients with liver cirrhosis complicated by hypersplenism and symptomatic gallstones were treated with combined LC and LS, while 58 (group 2) patients with liver cirrhosis and hypersplenism received LS alone. An additional 14 (group 3) patients who received traditional open procedures during the same period were included as controls. Data were retrospectively collected and reviewed in regard to demographic characteristics and preoperative, intraoperative and postoperative features. Differences between the three groups were assessed by statistical analysis. RESULTS: The three groups showed no significant differences in the demographic characteristics or preoperative status. However, the patients treated with LC and LS required significantly longer operative time, shorter postoperative stay as well as shorter time of return to the first oral intake, and suffered less intraoperative blood loss as well as fewer postoperative surgical infections than the patients treated with traditional open procedures (group 1 vs group 3, P < 0.05 for all). The patients treated with LC and LS showed no significant differences in the intraoperative and postoperative variables from those treated with LS alone (group 1 vs group 2). All patients showed significant improvements in the haematological responses (preoperative period vs postoperative period, P < 0.05 for all). None of the patients treated with LC and LS presented with any gallstone-associated symptoms following discharge, while the patients treated with the traditional open procedures expressed complaints of discomfort related to their surgical incisions. CONCLUSION: Consecutive LC and LS is an appropriate treatment option for liver cirrhosis patients with gallstones and hypersplenism, especially for those with Child-Pugh A and

  17. Adhesion behaviors on superhydrophobic surfaces.

    PubMed

    Zhu, Huan; Guo, Zhiguang; Liu, Weimin

    2014-04-18

    The adhesion behaviors of superhydrophobic surfaces have become an emerging topic to researchers in various fields as a vital step in the interactions between materials and organisms/materials. Controlling the chemical compositions and topological structures via various methods or technologies is essential to fabricate and modulate different adhesion properties, such as low-adhesion, high-adhesion and anisotropic adhesion on superhydrophobic surfaces. We summarize the recent developments in both natural superhydrophobic surfaces and artificial superhydrophobic surfaces with various adhesions and also pay attention to superhydrophobic surfaces switching between low- and high-adhesion. The methods to regulate or translate the adhesion of superhydrophobic surfaces can be considered from two perspectives. One is to control the chemical composition and change the surface geometric structure on the surfaces, respectively or simultaneously. The other is to provide external stimulations to induce transitions, which is the most common method for obtaining switchable adhesions. Additionally, adhesion behaviors on solid-solid interfaces, such as the behaviors of cells, bacteria, biomolecules and icing on superhydrophobic surfaces are also noticeable and controversial. This review is aimed at giving a brief and crucial overview of adhesion behaviors on superhydrophobic surfaces. PMID:24575424

  18. Clinical Recommendation: Labial Adhesions.

    PubMed

    Bacon, Janice L; Romano, Mary E; Quint, Elisabeth H

    2015-10-01

    Labial adhesions, also known as labial agglutination, are a common finding in prepubertal adolescents. They are defined as fusion of the labia minora in the midline or are termed vulvar adhesions when they occur below the labia minora (inner labia). Patients are often asymptomatic but might present with genitourinary complaints. The decision for treatment is based on symptoms. The mainstay of treatment in asymptomatic patients is conservative, with careful attention to vulvar hygiene and reassurance to parents. In symptomatic patients, topical treatment with estrogen and/or steroid cream is often curative. Less often, corrective surgery is necessary. Recurrence is common until a patient goes through puberty. These recommendations are intended for pediatric and gynecologic health care providers who care for pediatric and adolescent girls to facilitate diagnosis and treatment. PMID:26162697

  19. Environmentally compliant adhesive joining technology

    SciTech Connect

    Tira, J.S.

    1996-08-01

    Adhesive joining offers one method of assembling products. Advantages of adhesive joining/assembly include distribution of applied forces, lighter weight, appealing appearance, etc. Selecting environmentally safe adhesive materials and accompanying processes is paramount in today`s business climate if a company wants to be environmentally conscious and stay in business. Four areas of adhesive joining (adhesive formulation and selection, surface preparation, adhesive bonding process, waste and pollution generation/cleanup/management) all need to be carefully evaluated before adhesive joining is selected for commercial as well as military products. Designing for six sigma quality must also be addressed in today`s global economy. This requires material suppliers and product manufacturers to work even closer together.

  20. Development of phosphorylated adhesives

    NASA Technical Reports Server (NTRS)

    Bilow, N.; Giants, T. W.; Jenkins, R. K.; Campbell, P. L.

    1983-01-01

    The synthesis of epoxy prepolymers containing phosphorus was carried out in such a manner as to provide adhesives containing at least 5 percent of this element. The purpose of this was to impart fire retardant properties to the adhesive. The two epoxy derivatives, bis(4-glycidyl-oxyphenyl)phenylphosphine oxide and bis(4-glycidyl-2-methoxyphenyl)phenylphosphonate, and a curing agent, bis(3-aminophenyl)methylphosphine oxide, were used in conjunction with one another and along with conventional epoxy resins and curing agents to bond Tedlar and Polyphenylethersulfone films to Kerimid-glass syntactic foam-filled honeycomb structures. Elevated temperatures are required to cure the epoxy resins with the phosphorus-contaning diamine; however, when Tedlar is being bonded, lower curing temperatures must be used to avoid shrinkage and the concomitant formation of surface defects. Thus, the phosphorus-containing aromatic amine curing agent cannot be used alone, although it is possible to use it in conjunction with an aliphatic amine which would allow lower cure temperatures to be used. The experimental epoxy resins have not provided adhesive bonds quite as strong as those provided by Epon 828 when compared in peel tests, but the differences are not very significant. It should be noted, if optimum properties are to be realized. In any case the fire retardant characteristics of the neat resin systems obtained are quite pronounced, since in most cases the self-extinguishing properties are evident almost instantly when specimens are removed from a flame.

  1. Ceramic microstructure and adhesion

    NASA Technical Reports Server (NTRS)

    Buckley, D. H.

    1984-01-01

    When a ceramic is brought into contact with a ceramic, a polymer, or a metal, strong bond forces can develop between the materials. The bonding forces will depend upon the state of the surfaces, cleanliness and the fundamental properties of the two solids, both surface and bulk. Adhesion between a ceramic and another solid are discussed from a theoretical consideration of the nature of the surfaces and experimentally by relating bond forces to interface resulting from solid state contact. Surface properties of ceramics correlated with adhesion include, orientation, reconstruction and diffusion as well as the chemistry of the surface specie. Where a ceramic is in contact with a metal their interactive chemistry and bond strength is considered. Bulk properties examined include elastic and plastic behavior in the surficial regions, cohesive binding energies, crystal structures and crystallographic orientation. Materials examined with respect to interfacial adhesive interactions include silicon carbide, nickel zinc ferrite, manganese zinc ferrite, and aluminum oxide. The surfaces of the contacting solids are studied both in the atomic or molecularly clean state and in the presence of selected surface contaminants.

  2. Difficulty and Discrimination Parameters of Boston Naming Test Items in a Consecutive Clinical Series

    PubMed Central

    Pedraza, Otto; Sachs, Bonnie C.; Ferman, Tanis J.; Rush, Beth K.; Lucas, John A.

    2011-01-01

    The Boston Naming Test is one of the most widely used neuropsychological instruments; yet, there has been limited use of modern psychometric methods to investigate its properties at the item level. The current study used Item response theory to examine each item's difficulty and discrimination properties, as well as the test's measurement precision across the range of naming ability. Participants included 300 consecutive referrals to the outpatient neuropsychology service at Mayo Clinic in Florida. Results showed that successive items do not necessarily reflect a monotonic increase in psychometric difficulty, some items are inadequate to distinguish individuals at various levels of naming ability, multiple items provide redundant psychometric information, and measurement precision is greatest for persons within a low-average range of ability. These findings may be used to develop short forms, improve reliability in future test versions by replacing psychometrically poor items, and analyze profiles of intra-individual variability. PMID:21593059

  3. The Role of Glottal Surface Adhesion on Vocal Folds Biomechanics

    PubMed Central

    Bhattacharya, Pinaki; Siegmund, Thomas

    2014-01-01

    The airway surface liquid (ASL) is a very thin mucus layer and covers the vocal fold (VF) surface. Adhesion mediated by the ASL occurs during phonation as the VFs separate after collision. Such adhesion is hypothesized to determine voice quality and health. However, biomechanical insights into the adhesive processes during VF oscillation are lacking. Here, a computational study is reported on self-sustained VF vibration involving contact and adhesion. The VF structural model and the glottal airflow are considered fully three-dimensional. The mechanical behavior of the ASL is described through a constitutive traction–separation law where mucosal cohesive strength, cohesive energy and rupture length enter. Cohesive energy values considered are bound below by the cohesive energy of water at standard temperature and pressure. Cohesive strength values considered are bound above by prior reported data on the adhesive strength of mucosal surface of rat small intestine. This model introduces a mechanical length scale into the analysis. The sensitivity of various aspects of VF dynamics such as flow-declination rate, VF separation under adhesive condition and formation of multiple local fluid bridges is determined in relation to specific ASL adhesive properties. It is found that for the ASL considered here, the characteristics of the VF separation process are of debond type. Instabilities lead to the breakup of the bond area into several smaller bond patches. Such finding is consistent with in-vivo observations. PMID:25034504

  4. Gecko Adhesion on Wet and Dry Patterned Substrates

    PubMed Central

    Stark, Alyssa Y.; Palecek, Amanda M.; Argenbright, Clayton W.; Bernard, Craig; Brennan, Anthony B.; Niewiarowski, Peter H.; Dhinojwala, Ali

    2015-01-01

    Perhaps one of the most astounding characteristics of the gecko adhesive system is its versatility. Geckos can locomote across complex substrates in a variety of conditions with apparent ease. In contrast, many of our synthetic pressure sensitive adhesives fail on substrates that are dirty, wet or rough. Although many studies have investigated the effect of environmental challenges on performance, the interaction of multiple, potentially compromising variables is studied less often. Here we focus on substrate structure and surface water, both of which are highly relevant to the biological system and to synthetic design. To do this we utilized a highly controlled, patterned substrate (Sharklet®, by Sharklet® Technologies Inc.). This allowed us to test independently and jointly the effects of reduced surface area substrates, with a defined pattern, on adhesion in both air and water. Our results show that adhesion is not significantly impaired in air, whereas surface area and pattern significantly affect adhesion in water. These findings highlight the need to study multiple parameters that are relevant to the gecko adhesive system to further improve our understanding of the biological system and to design better, more versatile synthetics. PMID:26696412

  5. Gecko Adhesion on Wet and Dry Patterned Substrates.

    PubMed

    Stark, Alyssa Y; Palecek, Amanda M; Argenbright, Clayton W; Bernard, Craig; Brennan, Anthony B; Niewiarowski, Peter H; Dhinojwala, Ali

    2015-01-01

    Perhaps one of the most astounding characteristics of the gecko adhesive system is its versatility. Geckos can locomote across complex substrates in a variety of conditions with apparent ease. In contrast, many of our synthetic pressure sensitive adhesives fail on substrates that are dirty, wet or rough. Although many studies have investigated the effect of environmental challenges on performance, the interaction of multiple, potentially compromising variables is studied less often. Here we focus on substrate structure and surface water, both of which are highly relevant to the biological system and to synthetic design. To do this we utilized a highly controlled, patterned substrate (Sharklet®, by Sharklet® Technologies Inc.). This allowed us to test independently and jointly the effects of reduced surface area substrates, with a defined pattern, on adhesion in both air and water. Our results show that adhesion is not significantly impaired in air, whereas surface area and pattern significantly affect adhesion in water. These findings highlight the need to study multiple parameters that are relevant to the gecko adhesive system to further improve our understanding of the biological system and to design better, more versatile synthetics. PMID:26696412

  6. Chest wall reconstruction. Experience with 100 consecutive patients.

    PubMed Central

    Arnold, P G; Pairolero, P C

    1984-01-01

    Experience with 100 consecutive chest wall reconstructions during the past 7 years was reviewed. There were 52 female and 48 male patients with ages ranging from 13 to 78 years (average 53). Of the 100 patients, 42 had tumors of the chest wall, 19 had radiation necrosis, 24 had infected median sternotomies , and 15 had combinations of the three. Seventy-six patients underwent skeletal resection of the chest wall. An average of 5.7 ribs were resected in 63 patients. Total or partial sternectomies were performed in 29. Ninety-two patients underwent 142 muscle flaps: 77 pectoralis major, 29 latissimus dorsi, and 36 other muscles, including serratus anterior, rectus abdominis, and external oblique muscles. The omentum was transposed in ten patients. Chest wall skeletal defects were closed with Prolene mesh in 29 patients and with autogenous ribs in 11. Eighty-nine patients underwent primary closure of the skin. The 100 patients underwent an average of 2.1 operations. Hospitalization averaged 17.5 days. There was one perioperative death (29 days). Two patients required tracheostomy. Follow-up averaged 21.6 months. There were 24 late deaths. All 99 patients who were alive 30 days after operation had excellent results at the time of death or last follow-up. Images Figs. 2A-D. Figs. 3A-F. Figs. 4A-D. Figs. 4A-D. Fig. 5. Fig. 5. PMID:6732314

  7. Subdeltoid lipomas: a consecutive series of 13 cases.

    PubMed

    Carbone, Stefano; Candela, Vittorio; Passaretti, Daniele; Cinotti, Gianluca; Della Rocca, Carlo; Giannicola, Giuseppe; Gumina, Stefano

    2012-05-01

    We describe 13 consecutive cases of patients presenting with shoulder mass and limited function, and to whom we formulated a diagnosis of subdeltoid lipoma. Between 2002 and 2010, 14 patients had a diagnosis of subdeltoid lipoma. Of these, one was excluded from this review because of a concomitant cuff tear. Shoulder was evaluated with X-ray, MRI, EMG and pre-/post-operatively with constant score (CS) and subjective shoulder value (SSV). All patients had complete excision of the mass. Minimum follow-up was 12 months. In 14 cases, the lipoma was causing slight pain or discomfort, and in four cases (28.57 %), it was causing limitation of joint movement. EMG showed axillary nerve neuro apraxia in two cases (14.28 %). Preoperative CS and SSV were on average 80 and 80, respectively. At one-year follow-up, CS and SSV were meanly 92 and 95, respectively (p = 0.034). No recurrence of the lesion was noted. Subdeltoid lipomas quickly grow up and may cause compression of axillary nerve. Surgery is the treatment of these lesions if symptomatic. After complete excision, subdeltoid lipomas do not recur, and clinical signs disappear. Level of evidence Case series, Level IV. PMID:22528845

  8. Squamous Dysplasia of the Urinary Bladder: A Consecutive Cystectomy Series.

    PubMed

    Warrick, Joshua I; Kaag, Matthew; Raman, Jay D; Chan, Wilson; Tran, Truc; Kunchala, Sudhir; DeGraff, David; Chen, Guoli

    2016-06-01

    Squamous dysplasia of the urinary bladder is uncommon and may represent a precursor to invasive squamous cell carcinoma. Though significant focus has been devoted to squamous differentiation in invasive bladder cancer, relatively little attention has been given to squamous dysplasia. We methodically reviewed microscopic slides from a consecutive cystectomy series at our institution (n = 303; 2001-2014), with special attention given to squamous dysplasia and squamous differentiation within association invasive carcinoma. Of these 303 cases, 3% (9 cases) had squamous dysplasia. The majority (89%; 8/9) had a similar morphological appearance to squamous dysplasia of the head and neck (ie, cytological atypia, architectural disturbances, and abnormal keratinization). Invasive carcinoma was present in 230 of the cystectomy cases. Of these 230 cases with invasive carcinoma, 4% (8 cases) also had squamous dysplasia. The invasive carcinoma had evidence of squamous differentiation in all cases with concurrent squamous dysplasia. Concurrent flat urothelial carcinoma in situ was present in 3 of the 8 cases with both invasive carcinoma and squamous dysplasia. Squamous dysplasia was not associated with clinical outcomes data, including death from bladder cancer and bladder cancer recurrence. The data from this study indicate that squamous dysplasia is uncommon in the cystectomy setting, frequently has the morphology of head and neck dysplasia, and is often associated with invasive carcinoma with squamous differentiation. PMID:26860905

  9. A deformable model for tracking tumors across consecutive imaging studies

    PubMed Central

    Nosher, John L.; Schneider, M. D. Benjamin; Foran, David J.

    2009-01-01

    Objective A deformable registration technique was developed and evaluated to track and quantify tumor response to radiofrequency ablation for patients with liver malignancies. Materials and methods The method uses the combined power of global and local alignment of pre- and post-treatment computed tomography image data sets. The strategy of the algorithm is to infer volumetric deformation based upon surface displacements using a linearly elastic finite element model (FEM). Using this framework, the major challenge for tracking tumor location is not the tissue mechanical properties for FEM modeling but rather the evaluation of boundary conditions. Three different methods were systematically investigated to automatically determine the boundary conditions defined by the correspondences on liver surfaces. Results Using both 2D synthetic phantoms and imaged 3D beef liver data we performed gold standard registration while measuring the accuracy of non-rigid deformation. The fact that the algorithms could support mean displacement error of tumor deformation up to 2 mm indicates that this technique may serve as a useful tool for surgical interventions. The method was further demonstrated and evaluated using consecutive imaging studies for three liver cancer patients. Conclusion The FEM-based surface registration technique provides accurate tracking and monitoring of tumor and surrounding tissue during the course of treatment and follow-up. PMID:19774096

  10. Thoracic wall defects: surgical management of 205 consecutive patients

    SciTech Connect

    Pairolero, P.C.; Arnold, P.G.

    1986-07-01

    In this article, we review our experience during the past 9 years with 205 consecutive thoracic wall reconstructions. The 100 female and 105 male patients ranged in age from 12 to 85 years (mean, 53.4 years). One hundred fourteen patients had thoracic wall tumors, 56 had radiation necrosis, 56 had infected median sternotomy wounds, and 8 had costochondritis. Twenty-nine of these patients had combinations of the aforementioned conditions. One hundred seventy-eight patients underwent skeletal resection. A mean of 5.4 ribs were resected in 142 patients. Total or partial sternectomies were performed in 60. Skeletal defects were closed with prosthetic material in 66 patients and with autogenous ribs in 12. One hundred sixty-eight patients underwent 244 muscle flap procedures: 149 pectoralis major, 56 latissimus dorsi, 14 rectus abdominis, 13 serratus anterior, 8 external oblique, 2 trapezius, and 2 advancement of diaphragm. The omentum was transposed in 20 patients. The mean number of operations per patient was 1.9 (range, 1 to 8). The mean duration of hospitalization was 16.5 days. One perioperative death occurred (at 29 days). Four patients required tracheostomy. During a mean follow-up of 32.4 months, there were 49 late deaths, predominantly due to malignant disease. All 204 patients who were alive 30 days after operation had excellent surgical results at last follow-up examination or at the time of death due to causes unrelated to the reconstructive procedure.

  11. Aspiration-Related Deaths in 57 Consecutive Patients: Autopsy Study

    PubMed Central

    Hu, Xiaowen; Yi, Eunhee S.; Ryu, Jay H.

    2014-01-01

    Background Aspiration can cause a diverse spectrum of pulmonary disorders some of which can lead to death but can be difficult to diagnose. Patients and Methods The medical records and autopsy findings of 57 consecutive patients in whom aspiration was the immediate cause of death at Mayo Clinic (Rochester, MN, USA) over a 9-yr period, from January 1 2004 to December 31 2012 were analyzed. Results The median age at death was 72 years (range, 13–95 years) and included 39 (68%) males. The most common symptom before death was dyspnea (63%) and chest radiography revealed bilateral infiltrates in the majority (81%). Most common precipitating factors for aspiration were depressed consciousness (46%) and dysphagia (44%). Aspiration-related syndromes leading to death were aspiration pneumonia in 26 (46%), aspiration pneumonitis in 25 (44%), and large airway obstruction in 6 patients (11%). Aspiration was clinically unsuspected in 19 (33%) patients. Antimicrobial therapy had been empirically administered to most patients (90%) with aspiration pneumonia and aspiration pneumonitis. Conclusion We conclude aspiration-related deaths occur most commonly in the elderly with identifiable risks and presenting bilateral pulmonary infiltrates. One-third of these aspiration-related pulmonary syndromes were clinically unsuspected at the time of death. PMID:25076409

  12. Effective healthcare system response to consecutive Florida hurricanes.

    PubMed

    Banks, Laura L; Shah, Mark B; Richards, Michael E

    2007-01-01

    In September 2004, two consecutive hurricanes (Hurricane Frances and Hurricane Jeanne) made landfall in Stuart, FL, and created healthcare needs that overtaxed the capacity of the local healthcare system. To determine the character and structure of the response to these hurricanes, researchers from the University of New Mexico, Center for Disaster Medicine conducted both a structured written survey of employees and a guided group interview with healthcare system management. The written survey queried staff on topics related to their ability and willingness to get to work and stay at work during the storms. The roundtable interview with leadership resulted in analysis of the preexisting Emergency Operations Plan and its use during the storms, including preparation and execution of plans for staffing, facility operation, communication, community resource utilization, and recovery. In addition, the interaction with federally deployed Disaster Medical Assistance Teams was documented and reviewed. In general, prior planning on the part of the healthcare system in Stuart, FL, resulted in a successful response to both hurricanes. Employees were willing and able to provide the necessary care for patients during the hurricanes, overcoming many physical and emotional barriers that arose during the month-long response. These barriers included concern for the safety of family and pets, inoperable or insufficient communication methods, and damage to employees' personal property and homes. Recommendations for healthcare system preparedness and response were formulated by the researchers based on this healthcare system's successful response to back-to-back hurricanes, including recommendations for interacting with disaster medical resources. PMID:18297949

  13. Polyurethane adhesive ingestion.

    PubMed

    Fitzgerald, Kevin T; Bronstein, Alvin C

    2013-02-01

    Polyurethane adhesives are found in a large number of household products in the United States and are used for a variety of purposes. Several brands of these expanding wood glues (those containing diphenylmethane diisocyanate [MDI]) have the potential to form gastrointestinal (GI) foreign bodies if ingested. The ingested adhesive forms an expanding ball of glue in the esophagus and gastric lumen. This expansion is caused by a polymerization reaction using the heat, water, and gastric acids of the stomach. A firm mass is created that can be 4-8 times its original volume. As little as 2 oz of glue have been reported to develop gastric foreign bodies. The obstructive mass is reported to form within minutes of ingestion of the adhesive. The foreign body can lead to esophageal impaction and obstruction, airway obstruction, gastric outflow obstruction, mucosal hemorrhage, ulceration, laceration, perforation of the esophageal and gastric linings, and death. Clinical signs following ingestion include anorexia, lethargy, vomiting, tachypnea, and abdominal distention and pain, and typically develop within 12 hours. Clinical signs may depend upon the size of the mass. If left untreated, perforation and rupture of the esophagus or stomach can occur. The glue mass does not stick to the GI mucosa and is not always detectable on abdominal palpation. Radiographs are recommended to confirm the presence of the "glue-ball" foreign body, and radiographic evidence of the obstruction may be seen as early as 4-6 hours following ingestion. Emesis is contraindicated owing to the risk of aspiration of the glue into the respiratory tree or the subsequent lodging of the expanding glue mass in the esophagus. Likewise, efforts to dilute the glue and prevent the formation of the foreign body through administration of liquids, activated charcoal, or bulk-forming products to push the foreign body through the GI tract have proven ineffective. Even endoscopy performed to remove the foreign body has

  14. Lessons learned from two consecutive cleft lip and palate missions and the impact of patient education.

    PubMed

    Schönmeyr, Björn; Restrepo, Carolina; Wendby, Lisa; Gillenwater, Justin; Campbell, Alex

    2014-09-01

    Two consecutive cleft missions were conducted in Guwahati, northeastern India in December 2010 and January 2011. In the later mission, a standardized patient education program for postoperative care was introduced. The objective of this study was to retrospectively evaluate the impact of the patient education program on cleft lip complications in terms of wound infection and dehiscence. Two hundred ninety-eight cleft lip repairs were performed in the first mission and 220 (74%) returned for early follow-up. In the second mission, 356 patients were operated on and 252 (71%) returned for follow-up. From the first mission, 8 patients (3.7%) were diagnosed with lip wound infection and 21 patients (9.6%) with lip dehiscence. After the second mission, only 1 patient (0.4%) returned with a wound infection and 16 (6.4%) were diagnosed with dehiscence.Using binary logistic regression including age, cleft type, postoperative antibiotics, surgeon, and patient education program as covariates, the patient education program stood out as the only variable with a statistically significant impact on the incidence of postoperative wound infections. Even though the incidence of lip dehiscence was reduced by one third when the patient education program was utilized, our regression model singled out the surgeons as the only factor significantly related to this type of complication. Moreover, no benefits of postoperative antibiotic prophylaxis were found. Further analysis of the data also implied that the use of tissue adhesive as a compliment to sutures does not reduce the risk of dehiscence. PMID:25148620

  15. Elevated pretreatment serum levels of soluble vascular cell adhesion molecule 1 and lactate dehydrogenase as predictors of survival in cutaneous metastatic malignant melanoma.

    PubMed Central

    Franzke, A.; Probst-Kepper, M.; Buer, J.; Duensing, S.; Hoffmann, R.; Wittke, F.; Volkenandt, M.; Ganser, A.; Atzpodien, J.

    1998-01-01

    Very rapid progression of disease with a median survival of 6-9 months is a common feature of metastatic cutaneous malignant melanoma. Nevertheless, substantial variability of survival suggests that metastatic cutaneous malignant melanoma can be divided into several biological subgroups. Pretreatment serum levels of soluble adhesion molecules and various clinical parameters in cutaneous metastatic malignant melanoma were evaluated to determine their prognostic value. In this study pretreatment serum levels of soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble intercellular cell adhesion molecule 1 (sICAM-1), soluble endothelial leukocyte adhesion molecule 1 (sE-selectin) and multiple clinical factors were assessed in relation to overall survival of 97 consecutive patients with metastatic cutaneous malignant melanoma seen at our institution between May 1990 and April 1996. For statistical analysis, both univariate and multivariate Cox proportional-hazards models were used. Elevated pretreatment serum levels of sVCAM-1 (P < 0.005) and of lactate dehydrogenase (P < 0.002) were rendered statistically independent and were significantly associated with unfavourable outcome. Patients were assigned to one of three risk categories (low, intermediate and high) according to a cumulative risk score defined as the function of the sum of these two variables. There were significant differences in overall survival (P < 0.0001) between low- (n = 53, 5-year survival probability of 23.3%), intermediate- (n = 29, 5-year survival probability of 9.9%) and high-risk (n = 15) patients. Elevated pretreatment serum levels of sVCAM-1 and of lactate dehydrogenase correlate with poor outcome in metastatic cutaneous malignant melanoma. These data support risk stratification for future therapeutic trials and identify factors that need to be validated in prospective studies and may potentially influence decision-making in palliative management of patients with disseminated cutaneous

  16. JKR adhesion in cylindrical contacts

    NASA Astrophysics Data System (ADS)

    Sundaram, Narayan; Farris, T. N.; Chandrasekar, S.

    2012-01-01

    Planar JKR adhesive solutions use the half-plane assumption and do not permit calculation of indenter approach or visualization of adhesive force-displacement curves unless the contact is periodic. By considering a conforming cylindrical contact and using an arc crack analogy, we obtain closed-form indenter approach and load-contact size relations for a planar adhesive problem. The contact pressure distribution is also obtained in closed-form. The solutions reduce to known cases in both the adhesion-free and small-contact solution ( Barquins, 1988) limits. The cylindrical system shows two distinct regimes of adhesive behavior; in particular, contact sizes exceeding the critical (maximum) size seen in adhesionless contacts are possible. The effects of contact confinement on adhesive behavior are investigated. Some special cases are considered, including contact with an initial neat-fit and the detachment of a rubbery cylinder from a rigid cradle. A comparison of the cylindrical solution with the half-plane adhesive solution is carried out, and it indicates that the latter typically underestimates the adherence force. The cylindrical adhesive system is novel in that it possesses stable contact states that may not be attained even on applying an infinite load in the absence of adhesion.

  17. Early Requestive Development in Consecutive Third Language Learning

    ERIC Educational Resources Information Center

    Safont-Jorda, Maria-Pilar

    2011-01-01

    While research on early simultaneous bilingual acquisition is well-documented, studies on multiple language acquisition in early childhood are still needed. Existing studies have mainly focused on early simultaneous acquisition of three or more languages. Some attention has already been paid to early pragmatic differentiation and cross-linguistic…

  18. Adhesive sealing of dentin surfaces in vitro: A review

    PubMed Central

    Abu-Nawareg, Manar M; Zidan, Ahmed Z; Zhou, Jianfeng; Agee, Kelli; Chiba, Ayaka; Tagami, Jungi; Pashley, David H

    2016-01-01

    Purpose The purpose of this review is to describe the evolution of the use of dental adhesives to form a tight seal of freshly prepared dentin to protect the pulp from bacterial products, during the time between crown preparation and final cementum of full crowns. The evolution of these “immediate dentin sealants” follows the evolution of dental adhesives, in general. That is, they began with multiple-step, etch-and-rinse adhesives, and then switched to the use of simplified adhesives. Methods Literature was reviewed for evidence that bacteria or bacterial products diffusing across dentin can irritate pulpal tissues before and after smear layer removal. Smear layers can be solubilized by plaque organisms within 7–10 days if they are directly exposed to oral fluids. It is likely that smear layers covered by temporary restorations may last more than one month. As long as smear layers remain in place, they can partially seal dentin. Thus, many in vitro studies evaluating the sealing ability of adhesive resins use smear layer-covered dentin as a reference condition. Surprisingly, many adhesives do not seal dentin as well as do smear layers. Results Both in vitro and in vivo studies show that resin-covered dentin allows dentinal fluid to cross polymerized resins. The use of simplified single bottle adhesives to seal dentin was a step backwards. Currently, most authorities use either 3-step adhesives such as Scotchbond Multi-Purposea or OptiBond FLb or two-step self-etching primer adhesives, such as Clearfil SEc, Unifil Bondd or AdheSEe, respectfully. PMID:26846037

  19. Mechanisms of fluid production in smooth adhesive pads of insects.

    PubMed

    Dirks, Jan-Henning; Federle, Walter

    2011-07-01

    Insect adhesion is mediated by thin fluid films secreted into the contact zone. As the amount of fluid affects adhesive forces, a control of secretion appears probable. Here, we quantify for the first time the rate of fluid secretion in adhesive pads of cockroaches and stick insects. The volume of footprints deposited during consecutive press-downs decreased exponentially and approached a non-zero steady state, demonstrating the presence of a storage volume. We estimated its size and the influx rate into it from a simple compartmental model. Influx was independent of step frequency. Fluid-depleted pads recovered maximal footprint volumes within 15 min. Pads in stationary contact accumulated fluid along the perimeter of the contact zone. The initial fluid build-up slowed down, suggesting that flow is driven by negative Laplace pressure. Freely climbing stick insects left hardly any traceable footprints, suggesting that they save secretion by minimizing contact area or by recovering fluid during detachment. However, even the highest fluid production rates observed incur only small biosynthesis costs, representing less than 1 per cent of the resting metabolic rate. Our results show that fluid secretion in insect wet adhesive systems relies on simple physical principles, allowing for passive control of fluid volume within the contact zone. PMID:21208970

  20. Diffuse aspiration bronchiolitis: analysis of 20 consecutive patients*

    PubMed Central

    Hu, Xiaowen; Yi, Eunhee Suh; Ryu, Jay Hoon

    2015-01-01

    OBJECTIVE: Aspiration can cause a variety of pulmonary syndromes, some of which are not well recognized. The objective of this study was to assess the demographic, clinical, radiological, and histopathological correlates of diffuse aspiration bronchiolitis (DAB), a bronchiolocentric disorder caused by recurrent aspiration. METHODS: This was a retrospective study of 20 consecutive patients with DAB seen at the Mayo Clinic in Rochester, Minnesota, between January 1, 1998 and June 30, 2014. RESULTS: The median age of the patients was 56.5 years (range, 22-76 years), and the male/female ratio was 2.3:1.0. In 18 patients, the diagnosis of DAB was based on the results of a lung biopsy; in the 2 remaining patients, it was based on clinical and radiological features, together with documented aspiration observed in a videofluoroscopic swallow study. In 19 patients (95%), we identified predisposing factors for aspiration, including gastroesophageal reflux disease (GERD), drug abuse, and dysphagia. Common presenting features included cough, sputum production, dyspnea, and fever. Twelve patients (60%) had a history of recurrent pneumonia. In all of the patients, chest CT revealed bilateral pulmonary infiltrates consisting of micronodules and tree-in-bud opacities. In the majority of patients, interventions aimed at preventing recurrent aspiration (e.g., anti-GERD therapies) led to improvement in the symptoms of DAB. CONCLUSIONS: Young to middle-aged subjects with recognizable predisposing factors for aspiration and who report a history of recurrent pneumonia are at increased risk for DAB. Although DAB is not well recognized, certain chest CT features are characteristic of the disorder. PMID:25972969

  1. Does palliative home oxygen improve dyspnoea? A consecutive cohort study.

    PubMed

    Currow, D C; Agar, M; Smith, J; Abernethy, A P

    2009-06-01

    Palliative oxygen for refractory dyspnoea is frequently prescribed, even when the criteria for long-term home oxygen (based on survival, rather than the symptomatic relief of breathlessness) are not met. Little is known about how palliative home oxygen affects symptomatic breathlessness. A 4-year consecutive cohort from a regional community palliative care service in Western Australia was used to compare baseline breathlessness before oxygen therapy with dyspnoea sub-scales on the symptom assessment scores (SAS; 0-10) 1 and 2 weeks after the introduction of oxygen. Demographic and clinical characteristics of people who responded were included in a multi-variable logistic regression model. Of the study population (n = 5862), 21.1% (n = 1239) were prescribed oxygen of whom 413 had before and after data that could be included in this analysis. The mean breathlessness before home oxygen was 5.3 (SD 2.5; median 5; range 0-10). There were no significant differences overall at 1 or 2 weeks (P = 0.28) nor for any diagnostic sub-groups. One hundred and fifty people (of 413) had more than a 20% improvement in mean dyspnoea scores. In multi-factor analysis, neither the underlying diagnosis causing breathlessness nor the demographic factors predicted responders at 1 week. Oxygen prescribed on the basis of breathlessness alone across a large population predominantly with cancer does not improve breathlessness for the majority of people. Prospective randomised trials in people with cancer and non-cancer are needed to determine whether oxygen can reduce the progression of breathlessness compared to a control arm. PMID:19304806

  2. A Twelve-Year Consecutive Case Experience in Thoracic Reconstruction

    PubMed Central

    Chen, Jenny T.; Bonneau, Laura A.; Weigel, Tracey L.; Maloney, James D.; Castro, Francisco; Shulzhenko, Nikita

    2016-01-01

    Background: We describe the second largest contemporary series of flaps used in thoracic reconstruction. Methods: A retrospective review of patients undergoing thoracomyoplasty from 2001 to 2013 was conducted. Ninety-one consecutive patients were identified. Results: Thoracomyoplasty was performed for 67 patients with intrathoracic indications and 24 patients with chest wall defects. Malignancy and infection were the most common indications for reconstruction (P < 0.01). The latissimus dorsi (LD), pectoralis major, and serratus anterior muscle flaps remained the workhorses of reconstruction (LD and pectoralis major: 64% flaps in chest wall reconstruction; LD and serratus anterior: 85% of flaps in intrathoracic indication). Only 12% of patients required mesh. Only 6% of patients with <2 ribs resected required mesh when compared with 24% with 3–4 ribs, and 100% with 5 or more ribs resected (P < 0.01). Increased rib resections required in chest wall reconstruction resulted in a longer hospital stay (P < 0.01). Total comorbidities and complications were related to length of stay only in intrathoracic indication (P < 0.01). Average intubation time was significantly higher in patients undergoing intrathoracic indication (5.51 days) than chest wall reconstruction (0.04 days), P < 0.05. Average hospital stay was significantly higher in patients undergoing intrathoracic indication (23 days) than chest wall reconstruction (12 days), P < 0.05. One-year survival was most poor for intrathoracic indication (59%) versus chest wall reconstruction (83%), P = 0.0048. Conclusion: Thoracic reconstruction remains a safe and successful intervention that reliably treats complex and challenging problems, allowing more complex thoracic surgery problems to be salvaged. PMID:27257568

  3. Laparoscopic splenectomy: outcome and efficacy in 103 consecutive patients.

    PubMed Central

    Katkhouda, N; Hurwitz, M B; Rivera, R T; Chandra, M; Waldrep, D J; Gugenheim, J; Mouiel, J

    1998-01-01

    OBJECTIVE: To study the safety and efficacy of laparoscopic splenectomy (LS) in patients with predominantly benign hematologic disorders. SUMMARY BACKGROUND DATA: The technical feasibility of LS has been recently established. However, data regarding the efficacy of the procedure in a large cohort of patients are scarce. METHODS: One hundred three consecutive patients underwent LS between June 1992 and October 1997. Data were collected prospectively on all patients. RESULTS: Indications were idiopathic thrombocytopenic purpura (ITP), hereditary spherocytosis, autoimmune hemolytic anemia, thrombotic thrombocytopenic purpura, and others. Mean spleen size was 14 cm and mean weight was 263 g. Accessory spleens were found in 12 patients with ITP and in 5 patients without ITP. There were no deaths. Complications occurred in six patients, one requiring a second procedure for small bowel obstruction. Six patients received transfusions, and four procedures were converted to open splenectomy for bleeding. Mean surgical time was 161 minutes and was greater in the first 10 cases than the last 10. Mean postsurgical stay was 2.5 days. Thrombocytopenia resolved after surgery in 84% of patients with ITP, and hematocrit levels increased significantly in 70% of patients with chronic hemolytic anemias. A positive response was noted in 92% of patients with hereditary spherocytosis, without relapse for the duration of the observation. ITP relapsed in four patients during follow-up, three within 12 months. CONCLUSIONS: LS can be performed safely and effectively in a teaching institution. Rigorous technique will minimize capsular fractures, reducing the risk of splenosis. Accessory spleens can be successfully localized, thus improving response and limiting recurrence of ITP. LS should become the technique of choice for treatment of intractable benign hematologic disease. PMID:9790346

  4. Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes

    PubMed Central

    Strazza, Marianne; Azoulay-Alfaguter, Inbar; Pedoeem, Ariel; Mor, Adam

    2014-01-01

    T lymphocyte adhesion is required for multiple T cell functions, including migration to sites of inflammation and formation of immunological synapses with antigen presenting cells. T cells accomplish regulated adhesion by controlling the adhesive properties of integrins, a class of cell adhesion molecules consisting of heterodimeric pairs of transmembrane proteins that interact with target molecules on partner cells or extracellular matrix. The most prominent T cell integrin is lymphocyte function associated antigen (LFA)-1, composed of subunits αL and β2, whose target is the intracellular adhesion molecule (ICAM)-1. The ability of a T cell to control adhesion derives from the ability to regulate the affinity states of individual integrins. Inside-out signaling describes the process whereby signals inside a cell cause the external domains of integrins to assume an activated state. Much of our knowledge of these complex phenomena is based on mechanistic studies performed in simplified in vitro model systems. The T lymphocyte adhesion assay described here is an excellent tool that allows T cells to adhere to target molecules, under static conditions, and then utilizes a fluorescent plate reader to quantify adhesiveness. This assay has been useful in defining adhesion-stimulatory or inhibitory substances that act on lymphocytes, as well as characterizing the signaling events involved. Although described here for LFA-1 - ICAM-1 mediated adhesion; this assay can be readily adapted to allow for the study of other adhesive interactions (e.g. VLA-4 - fibronectin). PMID:24961998

  5. Stickiness--some fundamentals of adhesion.

    PubMed

    Gay, Cyprien

    2002-12-01

    We review some adhesion mechanisms that have been understood in the field of synthetic adhesives, and more precisely for adhesives that adhere instantaneously (a property named tackiness) and whose adhesive strength usually depends on the applied pressure (pressure-sensitive adhesives). The discussion includes effects of surface roughness, elasticity, cavitation, viscous and elastic fingering, substrate flexibility. PMID:21680396

  6. Small-bowel enema in the diagnosis of adhesive obstructions.

    PubMed

    Caroline, D F; Herlinger, H; Laufer, I; Kressel, H Y; Levine, M S

    1984-06-01

    The small-bowel enema was evaluated in 60 patients in whom a final diagnosis of adhesive obstruction was made by surgery or on the basis of clinical findings. Distinctive radiographic and clinical features were found with single versus multiple bands. While 72% of 32 single-band obstructions were graded as severe, this grading was given to only 34% of 18 obstructions by multiple bands. Extensive adhesions were demonstrated in 10 patients and presented varied radiographic features. The radiographic diagnosis of adhesive obstruction was found to be correct in 36 (87.8%) of 41 patients in whom a surgical diagnosis could subsequently be made. However, an incorrect radiologic diagnosis of obstruction by metastases was made in five patients. They form the basis for a discussion of the differential diagnosis. PMID:6609596

  7. Effect of adhesive thickness on adhesively bonded T-joint

    NASA Astrophysics Data System (ADS)

    Abdullah, A. R.; Afendi, Mohd; Majid, M. S. Abdul

    2013-12-01

    The aim of this work is to analyze the effect of adhesive thickness on tensile strength of adhesively bonded stainless steel T-joint. Specimens were made from SUS 304 Stainless Steel plate and SUS 304 Stainless Steel perforated plate. Four T-joint specimens with different adhesive thicknesses (0.5, 1.0, 1.5 and 2.0 mm) were made. Experiment result shows T-joint specimen with adhesive thickness of 1.0 mm yield highest maximum load. Identical T-joint specimen jointed by spot welding was also tested. Tensile test shows welded T-Joint had eight times higher tensile load than adhesively bonded T-joint. However, in low pressure application such as urea granulator chamber, high tensile strength is not mandatory. This work is useful for designer in fertilizer industry and others who are searching for alternative to spot welding.

  8. Improved Adhesion and Compliancy of Hierarchical Fibrillar Adhesives.

    PubMed

    Li, Yasong; Gates, Byron D; Menon, Carlo

    2015-08-01

    The gecko relies on van der Waals forces to cling onto surfaces with a variety of topography and composition. The hierarchical fibrillar structures on their climbing feet, ranging from mesoscale to nanoscale, are hypothesized to be key elements for the animal to conquer both smooth and rough surfaces. An epoxy-based artificial hierarchical fibrillar adhesive was prepared to study the influence of the hierarchical structures on the properties of a dry adhesive. The presented experiments highlight the advantages of a hierarchical structure despite a reduction of overall density and aspect ratio of nanofibrils. In contrast to an adhesive containing only nanometer-size fibrils, the hierarchical fibrillar adhesives exhibited a higher adhesion force and better compliancy when tested on an identical substrate. PMID:26167951

  9. Pharmacokinetics and Pulmonary Distribution of Clarithromycin and Rifampicin after Concomitant and Consecutive Administration in Foals.

    PubMed

    Berlin, Sarah; Spieckermann, Lena; Oswald, Stefan; Keiser, Markus; Lumpe, Stefan; Ullrich, Anett; Grube, Markus; Hasan, Mahmoud; Venner, Monica; Siegmund, Werner

    2016-03-01

    Drug interactions often result from multiple pharmacokinetic changes, such as after rifampicin (RIF) and clarithromycin (CLA) in the treatment of abscessing lung diseases. Comedication of RIF may interact with CLA disposition by either induction of presystemic elimination processes and/or inhibition of uptake mechanisms because it regulates gene transcription and modulates function of various CYP enzymes, multidrug efflux and uptake transporters for which CLA is a substrate. To distinguish the transcriptional changes from the modulating interaction components upon CLA absorption and pulmonary distribution, we initiated a repeated-dose study in 12 healthy foals with CLA (7.5 mg/kg, p.o., b.i.d.) in comedication with RIF (10 mg/kg, p.o., b.i.d.) given either concomitantly with CLA or consecutively 4 h after CLA. Affinity of CLA to human P-gp, MRP2, and MRP3 and to OCT1, OCT3, and PEPT1 was measured using Sf9-derived inside-out membrane vesicles and transfected HEK293 cells, respectively. ABCB1 (P-gp) induction by RIF and affinity of CLA to equine P-gp were studied using primary equine hepatocytes. Absolute bioavailability of CLA was reduced from ∼40% to below 5% after comedication of RIF in both schedules of administration, and Tmax occurred ∼2-3 h earlier. The loss of bioavailability was not associated with increased 14-hydroxyclarithromycin (14-OH-CLA) exposure. After consecutive dosing, absolute bioavailability and pulmonary penetration of CLA increased ∼2-fold compared to concomitant use. In vitro, CLA showed affinity to human and equine P-gp. Expression of ABCB1 mRNA was upregulated by RIF in 7 of 8 duodenal biopsy specimens and in primary equine hepatocytes. In conclusion, the major undesired influence of RIF on oral absorption and pulmonary distribution of CLA is associated with induction of intestinal P-gp. Consecutive administration to avoid competition with its intestinal uptake transport results in significantly, although not clinically relevant

  10. The electrostatic profile of consecutive Cβ atoms applied to protein structure quality assessment

    PubMed Central

    Chakraborty, Sandeep; Venkatramani, Ravindra; Rao, Basuthkar J.; Asgeirsson, Bjarni; Dandekar, Abhaya M.

    2014-01-01

    The structure of a protein provides insight into its physiological interactions with other components of the cellular soup. Methods that predict putative structures from sequences typically yield multiple, closely-ranked possibilities. A critical component in the process is the model quality assessing program (MQAP), which selects the best candidate from this pool of structures. Here, we present a novel MQAP based on the physical properties of sidechain atoms. We propose a method for assessing the quality of protein structures based on the electrostatic potential difference (EPD) of Cβ atoms in consecutive residues. We demonstrate that the EPDs of Cβ atoms on consecutive residues provide unique signatures of the amino acid types. The EPD of Cβ atoms are learnt from a set of 1000 non-homologous protein structures with a resolution cuto of 1.6 Å obtained from the PISCES database. Based on the Boltzmann hypothesis that lower energy conformations are proportionately sampled more, and on Annsen's thermodynamic hypothesis that the native structure of a protein is the minimum free energy state, we hypothesize that the deviation of observed EPD values from the mean values obtained in the learning phase is minimized in the native structure. We achieved an average specificity of 0.91, 0.94 and 0.93 on hg_structal, 4state_reduced and ig_structal decoy sets, respectively, taken from the Decoys `R' Us database. The source code and manual is made available at https://github.com/sanchak/mqap and permanently available on 10.5281/zenodo.7134. PMID:25506420

  11. Platelet adhesiveness in diabetes mellitus

    PubMed Central

    Shaw, S.; Pegrum, G. D.; Wolff, Sylvia; Ashton, W. L.

    1967-01-01

    Platelet adhesiveness has been assessed on whole blood from a series of 34 diabetics and 50 control subjects using adenosine diphosphate (A.D.P.) and by adherence to glass microspherules (ballotini). Using both techniques it was possible to demonstrate a significant increase in platelet adhesiveness in the diabetic patients. PMID:5614070

  12. Measuring Adhesion And Friction Forces

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa

    1991-01-01

    Cavendish balance adapted to new purpose. Apparatus developed which measures forces of adhesion and friction between specimens of solid materials in vacuum at temperatures from ambient to 900 degrees C. Intended primarily for use in studying adhesion properties of ceramics and metals, including silicon carbide, aluminum oxide, and iron-base amorphous alloys.

  13. 21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that...

  14. 21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that...

  15. 21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that...

  16. 21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that...

  17. 21 CFR 880.5240 - Medical adhesive tape and adhesive bandage.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Medical adhesive tape and adhesive bandage. 880... Personal Use Therapeutic Devices § 880.5240 Medical adhesive tape and adhesive bandage. (a) Identification. A medical adhesive tape or adhesive bandage is a device intended for medical purposes that...

  18. Biological adhesives and fastening devices

    NASA Astrophysics Data System (ADS)

    Wolpert, H. D.

    2012-04-01

    Sea creatures are a leading source to some of the more interesting discoveries in adhesives. Because sea water naturally breaks down even the strongest conventional adhesive, an alternative is important that could be used in repairing or fabricating anything that might have regular contact with moisture such as: Repairing broken and shattered bones, developing a surgical adhesive, use in the dental work, repairing and building ships, and manufacturing plywood. Some of nature's prototypes include the common mussel, limpet, some bacteria and abalone. As we learn more about these adhesives we are also developing non adhesive fasteners, such as mimicked after studying the octopus, burdock burrs (i.e. Velcro®) and the gecko.

  19. Hyaluronan-mediated cellular adhesion

    NASA Astrophysics Data System (ADS)

    Curtis, Jennifer

    2005-03-01

    Many cells surround themselves with a cushioning halo of polysaccharides that is further strengthened and organized by proteins. In fibroblasts and chrondrocytes, the primary component of this pericellular matrix is hyaluronan, a large linear polyanion. Hyaluronan production is linked to a variety of disease, developmental, and physiological processes. Cells manipulate the concentration of hyaluronan and hyaluronan receptors for numerous activities including modulation of cell adhesion, cell motility, and differentiation. Recent investigations by identify hyaluronan's role in mediating early-stage cell adhesion. An open question is how the cell removes the 0.5-10 micron thick pericellular matrix to allow for further mature adhesion events requiring nanometer scale separations. In this investigation, holographic optical tweezers are used to study the adhesion and viscoelastic properties of chondrocytes' pericellular matrix. Ultimately, we aim to shed further light on the spatial and temporal details of the dramatic transition from micron to nanometer gaps between the cell and its adhesive substrate.

  20. Corrugated pipe adhesive applicator apparatus

    DOEpatents

    Shirey, Ray A.

    1983-06-14

    Apparatus for coating selected portions of the troughs of a corrugated pipe within an adhesive includes a support disposed within the pipe with a reservoir containing the adhesive disposed on the support. A pump, including a spout, is utilized for supplying the adhesive from the reservoir to a trough of the pipe. A rotatable applicator is supported on the support and contacts the trough of the pipe. The applicator itself is sized so as to fit within the trough, and contacts the adhesive in the trough and spreads the adhesive in the trough upon rotation. A trough shield, supported by the support and disposed in the path of rotation of the applicator, is utilized to prevent the applicator from contacting selected portions of the trough. A locator head is also disposed on the support and provides a way for aligning the spout, the applicator, and the trough shield with the trough.

  1. Corrugated pipe adhesive applicator apparatus

    DOEpatents

    Shirey, R.A.

    1983-06-14

    Apparatus for coating selected portions of the troughs of a corrugated pipe with an adhesive includes a support disposed within the pipe with a reservoir containing the adhesive disposed on the support. A pump, including a spout, is utilized for supplying the adhesive from the reservoir to a trough of the pipe. A rotatable applicator is supported on the support and contacts the trough of the pipe. The applicator itself is sized so as to fit within the trough, and contacts the adhesive in the trough and spreads the adhesive in the trough upon rotation. A trough shield, supported by the support and disposed in the path of rotation of the applicator, is utilized to prevent the applicator from contacting selected portions of the trough. A locator head is also disposed on the support and provides a way for aligning the spout, the applicator, and the trough shield with the trough. 4 figs.

  2. Adhesion testing device

    NASA Technical Reports Server (NTRS)

    LaPeyronnie, Glenn M. (Inventor); Huff, Charles M. (Inventor)

    2010-01-01

    The present invention provides a testing apparatus and method for testing the adhesion of a coating to a surface. The invention also includes an improved testing button or dolly for use with the testing apparatus and a self aligning button hook or dolly interface on the testing apparatus. According to preferred forms, the apparatus and method of the present invention are simple, portable, battery operated rugged, and inexpensive to manufacture and use, are readily adaptable to a wide variety of uses, and provide effective and accurate testing results. The device includes a linear actuator driven by an electric motor coupled to the actuator through a gearbox and a rotatable shaft. The electronics for the device are contained in the head section of the device. At the contact end of the device, is positioned a self aligning button hook, attached below the load cell located on the actuator shaft.

  3. [Retention of adhesive bridges].

    PubMed

    Raes, F; De Boever, J

    1994-04-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rests, interocclusal clearance and cingulum stops is equally important. Including more teeth in the design does not necessarily lead to an improved retention. Besides the material and technical aspects, the whole clinical procedure needs much attention. The retention does not depend on one single factor, but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 80% can be obtained. PMID:11830965

  4. Epidural Lysis of Adhesions

    PubMed Central

    Lee, Frank; Jamison, David E.; Hurley, Robert W.

    2014-01-01

    As our population ages and the rate of spine surgery continues to rise, the use epidural lysis of adhesions (LOA) has emerged as a popular treatment to treat spinal stenosis and failed back surgery syndrome. There is moderate evidence that percutaneous LOA is more effective than conventional ESI for both failed back surgery syndrome, spinal stenosis, and lumbar radiculopathy. For cervical HNP, cervical stenosis and mechanical pain not associated with nerve root involvement, the evidence is anecdotal. The benefits of LOA stem from a combination of factors to include the high volumes administered and the use of hypertonic saline. Hyaluronidase has been shown in most, but not all studies to improve treatment outcomes. Although infrequent, complications are more likely to occur after epidural LOA than after conventional epidural steroid injections. PMID:24478895

  5. Epidural lysis of adhesions.

    PubMed

    Lee, Frank; Jamison, David E; Hurley, Robert W; Cohen, Steven P

    2014-01-01

    As our population ages and the rate of spine surgery continues to rise, the use epidural lysis of adhesions (LOA) has emerged as a popular treatment to treat spinal stenosis and failed back surgery syndrome. There is moderate evidence that percutaneous LOA is more effective than conventional ESI for both failed back surgery syndrome, spinal stenosis, and lumbar radiculopathy. For cervical HNP, cervical stenosis and mechanical pain not associated with nerve root involvement, the evidence is anecdotal. The benefits of LOA stem from a combination of factors to include the high volumes administered and the use of hypertonic saline. Hyaluronidase has been shown in most, but not all studies to improve treatment outcomes. Although infrequent, complications are more likely to occur after epidural LOA than after conventional epidural steroid injections. PMID:24478895

  6. Effect of fibril shape on adhesive properties

    NASA Astrophysics Data System (ADS)

    Soto, Daniel; Hill, Ginel; Parness, Aaron; Esparza, Noé; Cutkosky, Mark; Kenny, Tom

    2010-08-01

    Research into the gecko's adhesive system revealed a unique architecture for adhesives using tiny hairs. By using a stiff material (β-keratin) to create a highly structured adhesive, the gecko's system demonstrates properties not seen in traditional pressure-sensitive adhesives which use a soft, unstructured planar layer. In contrast to pressure sensitive adhesives, the gecko adhesive displays frictional adhesion, in which increased shear force allows it to withstand higher normal loads. Synthetic fibrillar adhesives have been fabricated but not all demonstrate this frictional adhesion property. Here we report the dual-axis force testing of single silicone rubber pillars from synthetic adhesive arrays. We find that the shape of the adhesive pillar dictates whether frictional adhesion or pressure-sensitive behavior is observed. This work suggests that both types of behavior can be achieved with structures much larger than gecko terminal structures. It also indicates that subtle differences in the shape of these pillars can significantly influence their properties.

  7. Amine-functionalized polypyrrole: Inherently cell adhesive conducting polymer.

    PubMed

    Lee, Jae Y; Schmidt, Christine E

    2015-06-01

    Electrically conducting polymers (CPs) have been recognized as novel biomaterials that can electrically communicate with biological systems. For their tissue engineering applications, CPs have been modified to promote cell adhesion for improved interactions between biomaterials and cells/tissues. Conventional approaches to improve cell adhesion involve the surface modification of CPs with biomolecules, such as physical adsorption of cell adhesive proteins and polycationic polymers, or their chemical immobilization; however, these approaches require additional multiple modification steps with expensive biomolecules. In this study, as a simple and effective alternative to such additional biomolecule treatment, we synthesized amine-functionalized polypyrrole (APPy) that inherently presents cell adhesion-supporting positive charges under physiological conditions. The synthesized APPy provides electrical activity in a moderate range and a hydrophilic surface compared to regular polypyrrole (PPy) homopolymers. Under both serum and serum-free conditions, APPy exhibited superior attachment of human dermal fibroblasts and Schwann cells compared to PPy homopolymer controls. Moreover, Schwann cell adhesion onto the APPy copolymer was at least similar to that on poly-l-lysine treated PPy controls. Our results indicate that amine-functionalized CP substrates will be useful to achieve good cell adhesion and potentially electrically stimulate various cells. In addition, amine functionality present on CPs can further serve as a novel and flexible platform to chemically tether various bioactive molecules, such as growth factors, antibodies, and chemical drugs. PMID:25294089

  8. Fluorescence Fluctuation Approaches to the Study of Adhesion and Signaling

    PubMed Central

    Bachir, Alexia I.; Kubow, Kristopher E.; Horwitz, Alan R.

    2013-01-01

    Cell–matrix adhesions are large, multimolecular complexes through which cells sense and respond to their environment. They also mediate migration by serving as traction points and signaling centers and allow the cell to modify the surroucnding tissue. Due to their fundamental role in cell behavior, adhesions are germane to nearly all major human health pathologies. However, adhesions are extremely complex and dynamic structures that include over 100 known interacting proteins and operate over multiple space (nm–µm) and time (ms–min) regimes. Fluorescence fluctuation techniques are well suited for studying adhesions. These methods are sensitive over a large spatiotemporal range and provide a wealth of information including molecular transport dynamics, interactions, and stoichiometry from a single time series. Earlier chapters in this volume have provided the theoretical background, instrumentation, and analysis algorithms for these techniques. In this chapter, we discuss their implementation in living cells to study adhesions in migrating cells. Although each technique and application has its own unique instrumentation and analysis requirements, we provide general guidelines for sample preparation, selection of imaging instrumentation, and optimization of data acquisition and analysis parameters. Finally, we review several recent studies that implement these techniques in the study of adhesions. PMID:23280111

  9. Double C-H amination by consecutive SET oxidations.

    PubMed

    Evoniuk, Christopher J; Hill, Sean P; Hanson, Kenneth; Alabugin, Igor V

    2016-06-01

    A new method for intramolecular C-H oxidative amination is based on a FeCl3-mediated oxidative reaction of anilines with activated sp(3) C-H bonds. The amino group plays multiple roles in the reaction cascade: (1) as the activating group in single-electron-transfer (SET) oxidation process, (2) as a directing group in benzylic/allylic C-H activation at a remote position, and (3) internal nucleophile trapping reactive intermediates formed from the C-H activation steps. These multielectron oxidation reactions proceed with catalytic amounts of Fe(iii) and inexpensive reagents. PMID:27170275

  10. Tunicate-mimetic nanofibrous hydrogel adhesive with improved wet adhesion.

    PubMed

    Oh, Dongyeop X; Kim, Sangsik; Lee, Dohoon; Hwang, Dong Soo

    2015-07-01

    The main impediment to medical application of biomaterial-based adhesives is their poor wet adhesion strength due to hydration-induced softening and dissolution. To solve this problem, we mimicked the wound healing process found in tunicates, which use a nanofiber structure and pyrogallol group to heal any damage on its tunic under sea water. We fabricated a tunicate-mimetic hydrogel adhesive based on a chitin nanofiber/gallic acid (a pyrogallol acid) composite. The pyrogallol group-mediated cross-linking and the nanofibrous structures improved the dissolution resistance and cohesion strength of the hydrogel compared to the amorphous polymeric hydrogels in wet condition. The tunicate-mimetic adhesives showed higher adhesion strength between fully hydrated skin tissues than did fibrin glue and mussel-mimetic adhesives. The tunicate mimetic hydrogels were produced at low cost from recyclable and abundant raw materials. This tunicate-mimetic adhesive system is an example of how natural materials can be engineered for biomedical applications. PMID:25841348

  11. The effect of surface water and wetting on gecko adhesion.

    PubMed

    Stark, Alyssa Y; Sullivan, Timothy W; Niewiarowski, Peter H

    2012-09-01

    Despite profound interest in the mechanics and performance of the gecko adhesive system, relatively few studies have focused on performance under conditions that are ecologically relevant to the natural habitats of geckos. Because geckos are likely to encounter surfaces that are wet, we used shear force adhesion measurements to examine the effect of surface water and toe pad wetting on the whole-animal performance of a tropical-dwelling gecko (Gekko gecko). To test the effect of surface wetting, we measured the shear adhesive force of geckos on three substrate conditions: dry glass, glass misted with water droplets and glass fully submerged in water. We also investigated the effect of wetting on the adhesive toe pad by soaking the toe pads prior to testing. Finally, we tested for repeatability of the adhesive system in each wetting condition by measuring shear adhesion after each step a gecko made under treatment conditions. Wetted toe pads had significantly lower shear adhesive force in all treatments (0.86 ± 0.09 N) than the control (17.96 ± 3.42 N), as did full immersion in water (0.44 ± 0.03 N). Treatments with droplets of water distributed across the surface were more variable and did not differ from treatments where the surface was dry (4.72 ± 1.59 N misted glass; 9.76 ± 2.81 N dry glass), except after the gecko took multiple steps. These findings suggest that surface water and the wetting of a gecko's adhesive toe pads may have significant consequences for the ecology and behavior of geckos living in tropical environments. PMID:22875772

  12. Synergistic and hierarchical adhesive and topographic guidance of BHK cells.

    PubMed

    Britland, S; Morgan, H; Wojiak-Stodart, B; Riehle, M; Curtis, A; Wilkinson, C

    1996-11-01

    Guided cell movement is a fundamental process in development and regeneration. We have used microengineered culture substrates to study the interaction between model topographic and adhesive guidance cues in steering BHK cell orientation. Grooves 0.1, 0.5, 1.0, 3.0, and 6.0 microm deep together with pitch-matched aminosilane tracks 5, 12, 25, 50, and 100 microm wide were fabricated on fused silica substrates using photolithographic and dry-etching techniques. The cues were presented to the cells individually, simultaneously in parallel and orthogonally opposed. Cells aligned most strongly to 25-microm-wide adhesive tracks and to 5-microm-wide, 6-microm-deep grooves. Stress fibers and vinculin were found to align with the adhesive tracks and to the grooves and ridges. Cell alignment was profoundly enhanced on all surfaces that presented both cues in parallel. Cells were able to switch alignment from ridges to grooves, and vice versa, depending on the location of superimposed adhesive tracks. Cells aligned preferentially to adhesive tracks superimposed orthogonally over grooves of matched pitch, traversing numerous grooves and ridges. The strength of the cues was more closely matched on narrower 3- and 6-microm-deep gratings with cells showing evidence of alignment to both cues. Confocal fluorescence microscopy revealed two groups of mutually opposed f-actin stress fibers within the same cell, one oriented with the topographic cues and the other with the adhesive cues. However, the adhesive response was consistently dominant. We conclude that cells are able to detect and respond to multiple guidance cues simultaneously. The adhesive and topographic guidance cues modeled here were capable of interacting both synergistically and hierarchically to guide cell orientation. PMID:8912725

  13. Wet Adhesion and Adhesive Locomotion of Snails on Anti-Adhesive Non-Wetting Surfaces

    PubMed Central

    Shirtcliffe, Neil J.; McHale, Glen; Newton, Michael I.

    2012-01-01

    Creating surfaces capable of resisting liquid-mediated adhesion is extremely difficult due to the strong capillary forces that exist between surfaces. Land snails use this to adhere to and traverse across almost any type of solid surface of any orientation (horizontal, vertical or inverted), texture (smooth, rough or granular) or wetting property (hydrophilic or hydrophobic) via a layer of mucus. However, the wetting properties that enable snails to generate strong temporary attachment and the effectiveness of this adhesive locomotion on modern super-slippy superhydrophobic surfaces are unclear. Here we report that snail adhesion overcomes a wide range of these microscale and nanoscale topographically structured non-stick surfaces. For the one surface which we found to be snail resistant, we show that the effect is correlated with the wetting response of the surface to a weak surfactant. Our results elucidate some critical wetting factors for the design of anti-adhesive and bio-adhesion resistant surfaces. PMID:22693563

  14. Marine Bioinspired Underwater Contact Adhesion.

    PubMed

    Clancy, Sean K; Sodano, Antonio; Cunningham, Dylan J; Huang, Sharon S; Zalicki, Piotr J; Shin, Seunghan; Ahn, B Kollbe

    2016-05-01

    Marine mussels and barnacles are sessile biofouling organisms that adhere to a number of surfaces in wet environments and maintain remarkably strong bonds. Previous synthetic approaches to mimic biological wet adhesive properties have focused mainly on the catechol moiety, present in mussel foot proteins (mfps), and especially rich in the interfacial mfps, for example, mfp-3 and -5, found at the interface between the mussel plaque and substrate. Barnacles, however, do not use Dopa for their wet adhesion, but are instead rich in noncatecholic aromatic residues. Due to this anomaly, we were intrigued to study the initial contact adhesion properties of copolymerized acrylate films containing the key functionalities of barnacle cement proteins and interfacial mfps, for example, aromatic (catecholic or noncatecholic), cationic, anionic, and nonpolar residues. The initial wet contact adhesion of the copolymers was measured using a probe tack testing apparatus with a flat-punch contact geometry. The wet contact adhesion of an optimized, bioinspired copolymer film was ∼15.0 N/cm(2) in deionized water and ∼9.0 N/cm(2) in artificial seawater, up to 150 times greater than commercial pressure-sensitive adhesive (PSA) tapes (∼0.1 N/cm(2)). Furthermore, maximum wet contact adhesion was obtained at ∼pH 7, suggesting viability for biomedical applications. PMID:27046671

  15. Adhesion molecules in cutaneous inflammation.

    PubMed

    Barker, J N

    1995-01-01

    As in other organs, leukocyte adhesion molecules and their ligands play a major role in cutaneous inflammatory events both by directing leukocyte trafficking and by their effects on antigen presentation. Skin biopsies of inflamed skin from patients with diseases such as as psoriasis or atopic dermatitis reveal up-regulation of endothelial cell expression of P- and E-selectin, vascular cell adhesion molecule 1 and intercellular adhesion molecule 1. Studies of evolving lesions following UVB irradiation, Mantoux reaction or application of contact allergen, demonstrate that expression of these adhesion molecules parallels leukocyte infiltration into skin. When cutaneous inflammation is widespread (e.g. in erythroderma), soluble forms of these molecules are detectable in serum. In vitro studies predict that peptide mediators are important regulatory factors for endothelial adhesion molecules. Intradermal injection of the cytokines interleukin 1, tumour necrosis factor alpha and interferon gamma into normal human skin leads to induction of endothelial adhesion molecules with concomitant infiltration of leukocytes. In addition, neuropeptides rapidly induce P-selectin translocation to the cell membrane and expression of E-selectin. Adhesion molecules also play a crucial role as accessory molecules in the presentation of antigen to T lymphocytes by Langerhans' cells. Expression of selectin ligands by Langerhans' cells is up-regulated by various inflammatory stimuli, suggesting that adhesion molecules may be important in Langerhans' cell migration. The skin, because of its accessibility, is an ideal organ in which to study expression of adhesion molecules and their relationship to inflammatory events. Inflammatory skin diseases are common and inhibition of lymphocyte accumulation in skin is likely to prove of great therapeutic benefit. PMID:7587640

  16. Nuclear Signaling from Cadherin Adhesion Complexes

    PubMed Central

    McCrea, Pierre D.; Maher, Meghan T.; Gottardi, Cara J.

    2015-01-01

    The arrival of multicellularity in evolution facilitated cell–cell signaling in conjunction with adhesion. As the ectodomains of cadherins interact with each other directly in trans (as well as in cis), spanning the plasma membrane and associating with multiple other entities, cadherins enable the transduction of “outside-in” or “inside-out” signals. We focus this review on signals that originate from the larger family of cadherins that are inwardly directed to the nucleus, and thus have roles in gene control or nuclear structure–function. The nature of cadherin complexes varies considerably depending on the type of cadherin and its context, and we will address some of these variables for classical cadherins versus other family members. Substantial but still fragmentary progress has been made in understanding the signaling mediators used by varied cadherin complexes to coordinate the state of cell–cell adhesion with gene expression. Evidence that cadherin intracellular binding partners also localize to the nucleus is a major point of interest. In some models, catenins show reduced binding to cadherin cytoplasmic tails favoring their engagement in gene control. When bound, cadherins may serve as stoichiometric competitors of nuclear signals. Cadherins also directly or indirectly affect numerous signaling pathways (e.g., Wnt, receptor tyrosine kinase, Hippo, NFκB, and JAK/STAT), enabling cell–cell contacts to touch upon multiple biological outcomes in embryonic development and tissue homeostasis. PMID:25733140

  17. Nuclear signaling from cadherin adhesion complexes.

    PubMed

    McCrea, Pierre D; Maher, Meghan T; Gottardi, Cara J

    2015-01-01

    The arrival of multicellularity in evolution facilitated cell-cell signaling in conjunction with adhesion. As the ectodomains of cadherins interact with each other directly in trans (as well as in cis), spanning the plasma membrane and associating with multiple other entities, cadherins enable the transduction of "outside-in" or "inside-out" signals. We focus this review on signals that originate from the larger family of cadherins that are inwardly directed to the nucleus, and thus have roles in gene control or nuclear structure-function. The nature of cadherin complexes varies considerably depending on the type of cadherin and its context, and we will address some of these variables for classical cadherins versus other family members. Substantial but still fragmentary progress has been made in understanding the signaling mediators used by varied cadherin complexes to coordinate the state of cell-cell adhesion with gene expression. Evidence that cadherin intracellular binding partners also localize to the nucleus is a major point of interest. In some models, catenins show reduced binding to cadherin cytoplasmic tails favoring their engagement in gene control. When bound, cadherins may serve as stoichiometric competitors of nuclear signals. Cadherins also directly or indirectly affect numerous signaling pathways (e.g., Wnt, receptor tyrosine kinase, Hippo, NFκB, and JAK/STAT), enabling cell-cell contacts to touch upon multiple biological outcomes in embryonic development and tissue homeostasis. PMID:25733140

  18. Adhesive Performance of Biomimetic Adhesive-Coated Biologic Scaffolds

    PubMed Central

    Murphy, John L.; Vollenweider, Laura; Xu, Fangmin; Lee, Bruce P.

    2010-01-01

    Surgical repair of a discontinuity in traumatized or degenerated soft tissues is traditionally accomplished using sutures. A current trend is to reinforce this primary repair with surgical grafts, meshes, or patches secured with perforating mechanical devices (i.e., sutures, staples, or tacks). These fixation methods frequently lead to chronic pain and mesh detachment. We developed a series of biodegradable adhesive polymers that are synthetic mimics of mussel adhesive proteins (MAPs), composed of 3,4-dihydroxyphenylalanine (DOPA)-derivatives, polyethylene glycol (PEG), and polycaprolactone (PCL). These polymers can be cast into films, and their mechanical properties, extent of swelling, and degradation rate can be tailored through the composition of the polymers as well as blending with additives. When coated onto a biologic mesh used for hernia repair, these adhesive constructs demonstrated adhesive strengths significantly higher than fibrin glue. With further development, a pre-coated bioadhesive mesh may represent a new surgical option for soft tissue repair. PMID:20919699

  19. Focal adhesion kinases in adhesion structures and disease.

    PubMed

    Eleniste, Pierre P; Bruzzaniti, Angela

    2012-01-01

    Cell adhesion to the extracellular matrix (ECM) is essential for cell migration, proliferation, and embryonic development. Cells can contact the ECM through a wide range of matrix contact structures such as focal adhesions, podosomes, and invadopodia. Although they are different in structural design and basic function, they share common remodeling proteins such as integrins, talin, paxillin, and the tyrosine kinases FAK, Pyk2, and Src. In this paper, we compare and contrast the basic organization and role of focal adhesions, podosomes, and invadopodia in different cells. In addition, we discuss the role of the tyrosine kinases, FAK, Pyk2, and Src, which are critical for the function of the different adhesion structures. Finally, we discuss the essential role of these tyrosine kinases from the perspective of human diseases. PMID:22888421

  20. Focal Adhesion Kinases in Adhesion Structures and Disease

    PubMed Central

    Eleniste, Pierre P.; Bruzzaniti, Angela

    2012-01-01

    Cell adhesion to the extracellular matrix (ECM) is essential for cell migration, proliferation, and embryonic development. Cells can contact the ECM through a wide range of matrix contact structures such as focal adhesions, podosomes, and invadopodia. Although they are different in structural design and basic function, they share common remodeling proteins such as integrins, talin, paxillin, and the tyrosine kinases FAK, Pyk2, and Src. In this paper, we compare and contrast the basic organization and role of focal adhesions, podosomes, and invadopodia in different cells. In addition, we discuss the role of the tyrosine kinases, FAK, Pyk2, and Src, which are critical for the function of the different adhesion structures. Finally, we discuss the essential role of these tyrosine kinases from the perspective of human diseases. PMID:22888421

  1. Photovoltaic module with adhesion promoter

    SciTech Connect

    Xavier, Grace

    2013-10-08

    Photovoltaic modules with adhesion promoters and methods for fabricating photovoltaic modules with adhesion promoters are described. A photovoltaic module includes a solar cell including a first surface and a second surface, the second surface including a plurality of interspaced back-side contacts. A first glass layer is coupled to the first surface by a first encapsulating layer. A second glass layer is coupled to the second surface by a second encapsulating layer. At least a portion of the second encapsulating layer is bonded directly to the plurality of interspaced back-side contacts by an adhesion promoter.

  2. Notch-Mediated Cell Adhesion

    PubMed Central

    Murata, Akihiko; Hayashi, Shin-Ichi

    2016-01-01

    Notch family members are generally recognized as signaling molecules that control various cellular responses in metazoan organisms. Early fly studies and our mammalian studies demonstrated that Notch family members are also cell adhesion molecules; however, information on the physiological roles of this function and its origin is limited. In this review, we discuss the potential present and ancestral roles of Notch-mediated cell adhesion in order to explore its origin and the initial roles of Notch family members dating back to metazoan evolution. We hypothesize that Notch family members may have initially emerged as cell adhesion molecules in order to mediate multicellularity in the last common ancestor of metazoan organisms. PMID:26784245

  3. Adhesives from modified soy protein

    DOEpatents

    Sun, Susan; Wang, Donghai; Zhong, Zhikai; Yang, Guang

    2008-08-26

    The, present invention provides useful adhesive compositions having similar adhesive properties to conventional UF and PPF resins. The compositions generally include a protein portion and modifying ingredient portion selected from the group consisting of carboxyl-containing compounds, aldehyde-containing compounds, epoxy group-containing compounds, and mixtures thereof. The composition is preferably prepared at a pH level at or near the isoelectric point of the protein. In other preferred forms, the adhesive composition includes a protein portion and a carboxyl-containing group portion.

  4. Wear mechanism based on adhesion

    NASA Technical Reports Server (NTRS)

    Yamamoto, T.; Buckley, D. H.

    1982-01-01

    Various concepts concerning wear mechanisms and deformation behavior observed in the sliding wear track are surveyed. The mechanisms for wear fragment formation is discussed on the basis of adhesion. The wear process under unlubricated sliding conditions is explained in relation to the concept of adhesion at the interface during the sliding process. The mechanism for tearing away the surface layer from the contact area and forming the sliding track contour is explained by assuming the simplified process of material removal based on the adhesion theory.

  5. Interfacial adhesion of carbon fibers

    NASA Technical Reports Server (NTRS)

    Bascom, Willard D.

    1987-01-01

    Relative adhesion strengths between AS4, AS1, and XAS carbon fibers and thermoplastic polymers were determined using the embedded single filament test. Polymers studied included polycarbonate, polyphenylene oxide, polyetherimide, polysulfone, polyphenylene oxide blends with polystyrene, and polycarbonate blends with a polycarbonate polysiloxane block copolymer. Fiber surface treatments and sizings improved adhesion somewhat, but adhesion remained well below levels obtained with epoxy matrices. An explanation for the differences between the Hercules and Grafil fibers was sought using X ray photon spectroscopy, wetting, scanning electron microscopy and thermal desorption analysis.

  6. Notch-Mediated Cell Adhesion.

    PubMed

    Murata, Akihiko; Hayashi, Shin-Ichi

    2016-01-01

    Notch family members are generally recognized as signaling molecules that control various cellular responses in metazoan organisms. Early fly studies and our mammalian studies demonstrated that Notch family members are also cell adhesion molecules; however, information on the physiological roles of this function and its origin is limited. In this review, we discuss the potential present and ancestral roles of Notch-mediated cell adhesion in order to explore its origin and the initial roles of Notch family members dating back to metazoan evolution. We hypothesize that Notch family members may have initially emerged as cell adhesion molecules in order to mediate multicellularity in the last common ancestor of metazoan organisms. PMID:26784245

  7. Advances in light curing adhesives

    NASA Astrophysics Data System (ADS)

    Bachmann, Andy

    2001-11-01

    This paper describes the development of a new family of light curing adhesives containing a new reactive additive previously not used in optical grade light curing adhesives are obtained with the addition of functionalized cellulositics. Outgassing as low as 10-6 grams/gram has been observed based on headspace sampling. Other additives have lowered the shrinkage rates of positioning adhesives from near 1 percent to less than 0.1 percent with fractional, percentage movements over thermal range of -40 degrees C to +200 degrees C.

  8. [Retention of adhesive bridges].

    PubMed

    Raes, F; De Boever, J

    1990-01-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. To ensure an adequate retention over a number of years different factors have to be considered. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin (Panavia Ex) are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rets, interocclusal clearance of 0.4 mm and cingulum stops is equally important. Care should be taken not to remove all the enamel in the cervical region in preparing a mini chamfer. Including more teeth in the design does not necessarily lead to an improved retention. Teeth with a different mobility should not be included in the same bridge. Besides the material and technical aspects, the whole clinical procedure needs much attention. Only an exact impression, a precise model and a reliable casting technique will provide a metal frame with an optimal marginal adaptation and a close fit. The retention does not depend on one single factor but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 90% can be obtained. PMID:2077574

  9. Seafood delicacy makes great adhesive

    SciTech Connect

    Idaho National Laboratory - Frank Roberto, Heather Silverman

    2008-03-26

    Technology from Mother Nature is often hard to beat, so Idaho National Laboratory scientistsgenetically analyzed the adhesive proteins produced by blue mussels, a seafood delicacy. Afterobtaining full-length DNA sequences encoding these proteins, reprod

  10. Seafood delicacy makes great adhesive

    ScienceCinema

    Idaho National Laboratory - Frank Roberto, Heather Silverman

    2010-01-08

    Technology from Mother Nature is often hard to beat, so Idaho National Laboratory scientistsgenetically analyzed the adhesive proteins produced by blue mussels, a seafood delicacy. Afterobtaining full-length DNA sequences encoding these proteins, reprod

  11. The incidence of Gorlin syndrome in 173 consecutive cases of medulloblastoma.

    PubMed Central

    Evans, D. G.; Farndon, P. A.; Burnell, L. D.; Gattamaneni, H. R.; Birch, J. M.

    1991-01-01

    We have investigated the incidence of Gorlin syndrome (GS) in patients with the childhood brain tumour, medulloblastoma. One hundred and seventy-three consecutive cases of medulloblastoma in the North-West Regional Health Authority between 1954 and 1989 (Manchester Regional Health Board before 1974) were studied. After review of case notes, X-rays and health surveys only 2/173 cases had evidence supporting a diagnosis of GS. A further case at 50% risk of GS died of a brain tumour aged 4 years. The incidence of GS in medulloblastoma is, therefore, probably between 1-2%. A population based study of GS in the region started in 1983 was used to assess the incidence of medulloblastoma in GS, which was found to be between 3-5%. This figure is lower than previous estimates, but this is the first population based study undertaken. In view of the early age of onset in GS (mean 2 years) children presenting with medulloblastoma, especially under 5 years, should be examined for signs of the syndrome. Those at high risk of developing multiple invasive basal cell carcinomata will then be identified. PMID:1931625

  12. The bone-added osteotome sinus floor elevation technique: multicenter retrospective report of consecutively treated patients.

    PubMed

    Rosen, P S; Summers, R; Mellado, J R; Salkin, L M; Shanaman, R H; Marks, M H; Fugazzotto, P A

    1999-01-01

    A retrospective clinical evaluation of patients consecutively treated from multiple centers was performed. The treatment of these patients utilized the bone-added osteotome sinus floor elevation (BAOSFE) procedure with immediate implant fixation. The BAOSFE method employs a specific set of osteotome instruments to tent the sinus membrane with bone graft material placed through the osteotomy site. A total of 174 implants was placed in 101 patients. Implants were of both screw and cylinder shapes with machined, titanium plasma-sprayed, and hydroxyapatite surfaces from various manufacturers. The 9 participating clinicians used autografts, allografts, and xenografts alone or in various combinations, and the type of graft was selected by the individual clinicians. The choice of graft material did not appear to influence survival rates. Loading periods varied from 6 to 66 months. The survival rate was 96% or higher when pretreatment bone height was 5 mm or more and dropped to 85.7% when pretreatment bone height was 4 mm or less. The most important factor influencing implant survival with the BAOSFE was the preexisting bone height between the sinus floor and crest. This short-term retrospective investigation suggests that the BAOSFE can be a successful procedure with a wide variety of implant types and grafting procedures. PMID:10612923

  13. Watch and learn: seeing is better than doing when acquiring consecutive motor tasks.

    PubMed

    Larssen, Beverley C; Ong, Nicole T; Hodges, Nicola J

    2012-01-01

    During motor adaptation learning, consecutive physical practice of two different tasks compromises the retention of the first. However, there is evidence that observational practice, while still effectively aiding acquisition, will not lead to interference and hence prove to be a better practice method. Observers and Actors practised in a clockwise (Task A) followed by a counterclockwise (Task B) visually rotated environment, and retention was immediately assessed. An Observe-all and Act-all group were compared to two groups who both physically practised Task A, but then only observed (ObsB) or did not see or practice Task B (NoB). The two observer groups and the NoB control group better retained Task A than Actors, although importantly only the observer groups learnt Task B. RT data and explicit awareness of the rotation suggested that the observers had acquired their respective tasks in a more strategic manner than Actor and Control groups. We conclude that observational practice benefits learning of multiple tasks more than physical practice due to the lack of updating of implicit, internal models for aiming in the former. PMID:22723909

  14. The impact of consecutive freshwater trimix dives at altitude on human cardiovascular function.

    PubMed

    Lozo, Mislav; Madden, Dennis; Gunjaca, Grgo; Ljubkovic, Marko; Marinovic, Jasna; Dujic, Zeljko

    2015-03-01

    Self-contained underwater breathing apparatus (SCUBA) diving is regularly associated with numerous asymptomatic changes in cardiovascular function. Freshwater SCUBA diving presents unique challenges compared with open sea diving related to differences in water density and the potential for dive locations at altitude. The aim of this study was to evaluate the impact of freshwater trimix diving at altitude on human cardiovascular function. Ten divers performed two dives in consecutive days at 294 m altitude with the surface interval of 24 h. Both dives were at a depth of 45 m with total dive time 29 and 26 min for the first and second dive, respectively. Assessment of venous gas embolization, hydration status, cardiac function and arterial stiffness was performed. Production of venous gas emboli was low, and there were no significant differences between the dives. After the first dive, diastolic blood pressure was significantly reduced, which persisted up to 24 h. Left ventricular stroke volume decreased, and heart rate increased after both dives. Pulse wave velocity was unchanged following the dives. However, the central and peripheral augmentation index became more negative after both dives, indicating reduced wave reflection. Ejection duration and round trip travel time were prolonged 24 h after the first dive, suggesting longer-lasting suppression of cardiac and endothelial function. This study shows that freshwater trimix dives with conservative profiles and low venous gas bubble loads can result in multiple asymptomatic acute cardiovascular changes some of which were present up to 24 h after dive. PMID:24528802

  15. Engineering invitro cellular microenvironment using polyelectrolyte multilayer films to control cell adhesion and for drug delivery applications

    NASA Astrophysics Data System (ADS)

    Kidambi, Srivatsan

    Over the past decades, the development of new methods for fabricating thin films that provide precise control of the three-dimensional topography and cell adhesion has generated lots of interest. These films could lead to significant advances in the fields of tissue engineering, drug delivery and biosensors which have become increasingly germane areas of research in the field of chemical engineering. The ionic layer-by-layer (LbL) assembly technique called "Polyelectrolyte Multilayers (PEMs)", introduced by Decher in 1991, has emerged as a versatile and inexpensive method of constructing polymeric thin films, with nanometer-scale control of ionized species. PEMs have long been utilized in such applications as sensors, eletrochromics, and nanomechanical thin films but recently they have also been shown to be excellent candidates for biomaterial applications. In this thesis, we engineered these highly customizable PEM thin films to engineer in vitro cellular microenvironments to control cell adhesion and for drug delivery applications. PEM films were engineered to control the adhesion of primary hepatocytes and primary neurons without the aid of adhesive proteins/ligands. We capitalized upon the differential cell attachment and spreading of primary hepatocytes and neurons on poly(diallyldimethylammoniumchloride) (PDAC) and sulfonated polystyrene (SPS) surfaces to make patterned co-cultures of primary hepatocytes/fibroblasts and primary neurons/astrocytes on the PEM surfaces. In addition, we developed self-assembled monolayer (SAM) patterns of m-d-poly(ethylene glycol) (m-dPEG) acid molecules onto PEMs. The created m-dPEG acid monolayer patterns on PEMs acted as resistive templates, and thus prevented further deposits of consecutive poly(anion)/poly(cation) pairs of charged particles and resulted in the formation of three-dimensional (3-D) patterned PEM films or selective particle depositions atop the original multilayer thin films. These new patterned and structured

  16. Fibrillar Adhesive for Climbing Robots

    NASA Technical Reports Server (NTRS)

    Pamess, Aaron; White, Victor E.

    2013-01-01

    A climbing robot needs to use its adhesive patches over and over again as it scales a slope. Replacing the adhesive at each step is generally impractical. If the adhesive or attachment mechanism cannot be used repeatedly, then the robot must carry an extra load of this adhesive to apply a fresh layer with each move. Common failure modes include tearing, contamination by dirt, plastic deformation of fibers, and damage from loading/ unloading. A gecko-like fibrillar adhesive has been developed that has been shown useful for climbing robots, and may later prove useful for grasping, anchoring, and medical applications. The material consists of a hierarchical fibrillar structure that currently contains two levels, but may be extended to three or four levels in continuing work. The contacting level has tens of thousands of microscopic fibers made from a rubberlike material that bend over and create intimate contact with a surface to achieve maximum van der Waals forces. By maximizing the real area of contact that these fibers make and minimizing the bending energy necessary to achieve that contact, the net amount of adhesion has been improved dramatically.

  17. Venous Stenosis After Transvenous Lead Placement: A Study of Outcomes and Risk Factors in 212 Consecutive Patients

    PubMed Central

    Abu-El-Haija, Basil; Bhave, Prashant D; Campbell, Dwayne N; Mazur, Alexander; Hodgson-Zingman, Denice M; Cotarlan, Vlad; Giudici, Michael C

    2015-01-01

    Background Venous stenosis is a common complication of transvenous lead implantation, but the risk factors for venous stenosis have not been well defined to date. This study was designed to evaluate the incidence of and risk factors for venous stenosis in a large consecutive cohort. Methods and Results A total of 212 consecutive patients (136 male, 76 female; mean age 69 years) with existing pacing or implantable cardioverter-defibrillator systems presented for generator replacement, lead revision, or device upgrade with a mean time since implantation of 6.2 years. Venograms were performed and percentage of stenosis was determined. Variables studied included age, sex, number of leads, lead diameter, implant duration, insulation material, side of implant, and anticoagulant use. Overall, 56 of 212 patients had total occlusion of the subclavian or innominate vein (26%). There was a significant association between the number of leads implanted and percentage of venous stenosis (P =0.012). Lead diameter, as an independent variable, was not a risk factor; however, greater sum of the lead diameters implanted was a predictor of subsequent venous stenosis (P =0.009). Multiple lead implant procedures may be associated with venous stenosis (P =0.057). No other variables approached statistical significance. Conclusions A significant association exists between venous stenosis and the number of implanted leads and also the sum of the lead diameters. When combined with multiple implant procedures, the incidence of venous stenosis is increased. PMID:26231843

  18. Investigation of organic adhesives for hybrid microcircuits

    NASA Technical Reports Server (NTRS)

    Perkins, K. L.; Licari, J. J.

    1975-01-01

    The properties of organic adhesives were investigated to acquire information for a guideline document regarding the selection of adhesives for use in high reliability hybrid microcircuits. Specifically, investigations were made of (1) alternate methods for determining the outgassing of cured adhesives, (2) effects of long term aging at 150 C on the electrical properties of conductive adhesives, (3) effects of shelf life age on adhesive characteristics, (4) bond strengths of electrically conductive adhesives on thick film gold metallization, (5) a copper filled adhesive, (6) effects of products outgassed from cured adhesives on device electrical parameters, (7) metal migration from electrically conductive adhesives, and (8) ionic content of electrically insulative adhesives. The tests performed during these investigations are described, and the results obtained are discussed.

  19. Successional trajectories of rhizosphere bacterial communities over consecutive seasons

    SciTech Connect

    Shi, Shengjing; Nuccio, Erin; Herman, Donald J.; Rijkers, Ruud; Estera, Katerina; Li, Jiabao; da Rocha, Ulisses Nunes; He, Zhili; Pett-Ridge, Jennifer; Brodie, Eoin L.; Zhou, Jizhong; Firestone, Mary

    2015-08-04

    succession that was consistent and repeatable over two growing seasons. There are few studies assessing the reproducibility over multiple seasons. Through the growing season, the rhizosphere community became progressively less diverse, likely reflecting root homogenization of soil microniches. Phylogenetic clustering of the rhizosphere dynamic taxa suggests evolutionary adaptation to Avena roots. The reproducibility of rhizosphere succession and the apparent phylogenetic conservation of rhizosphere competence traits suggest adaptation of the indigenous bacterial community to this common grass over the many decades of its presence.

  20. Successional trajectories of rhizosphere bacterial communities over consecutive seasons

    DOE PAGESBeta

    Shi, Shengjing; Nuccio, Erin; Herman, Donald J.; Rijkers, Ruud; Estera, Katerina; Li, Jiabao; da Rocha, Ulisses Nunes; He, Zhili; Pett-Ridge, Jennifer; Brodie, Eoin L.; et al

    2015-08-04

    over two growing seasons. There are few studies assessing the reproducibility over multiple seasons. Through the growing season, the rhizosphere community became progressively less diverse, likely reflecting root homogenization of soil microniches. Phylogenetic clustering of the rhizosphere dynamic taxa suggests evolutionary adaptation to Avena roots. The reproducibility of rhizosphere succession and the apparent phylogenetic conservation of rhizosphere competence traits suggest adaptation of the indigenous bacterial community to this common grass over the many decades of its presence.« less

  1. 34 CFR 237.31 - May a fellowship be awarded for two consecutive years?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 1 2012-07-01 2012-07-01 false May a fellowship be awarded for two consecutive years... ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION CHRISTA MCAULIFFE FELLOWSHIP PROGRAM What Conditions Must Be Met by Fellows? § 237.31 May a fellowship be awarded for two consecutive years? A...

  2. 34 CFR 237.31 - May a fellowship be awarded for two consecutive years?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false May a fellowship be awarded for two consecutive years... ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION CHRISTA MCAULIFFE FELLOWSHIP PROGRAM What Conditions Must Be Met by Fellows? § 237.31 May a fellowship be awarded for two consecutive years? A...

  3. 34 CFR 237.31 - May a fellowship be awarded for two consecutive years?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 1 2013-07-01 2013-07-01 false May a fellowship be awarded for two consecutive years... ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION CHRISTA MCAULIFFE FELLOWSHIP PROGRAM What Conditions Must Be Met by Fellows? § 237.31 May a fellowship be awarded for two consecutive years? A...

  4. 34 CFR 237.31 - May a fellowship be awarded for two consecutive years?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 1 2014-07-01 2014-07-01 false May a fellowship be awarded for two consecutive years... ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION CHRISTA MCAULIFFE FELLOWSHIP PROGRAM What Conditions Must Be Met by Fellows? § 237.31 May a fellowship be awarded for two consecutive years? A...

  5. 34 CFR 237.31 - May a fellowship be awarded for two consecutive years?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false May a fellowship be awarded for two consecutive years... ELEMENTARY AND SECONDARY EDUCATION, DEPARTMENT OF EDUCATION CHRISTA MCAULIFFE FELLOWSHIP PROGRAM What Conditions Must Be Met by Fellows? § 237.31 May a fellowship be awarded for two consecutive years? A...

  6. Highly Multiplexed Imaging Uncovers Changes in Compositional Noise within Assembling Focal Adhesions.

    PubMed

    Harizanova, Jana; Fermin, Yessica; Malik-Sheriff, Rahuman S; Wieczorek, Jakob; Ickstadt, Katja; Grecco, Hernán E; Zamir, Eli

    2016-01-01

    Integrin adhesome proteins bind each other in alternative manners, forming within the cell diverse cell-matrix adhesion sites with distinct properties. An intriguing question is how such modular assembly of adhesion sites is achieved correctly solely by self-organization of their components. Here we address this question using high-throughput multiplexed imaging of eight proteins and two phosphorylation sites in a large number of single focal adhesions. We found that during the assembly of focal adhesions the variances of protein densities decrease while the correlations between them increase, suggesting reduction in the noise levels within these structures. These changes correlate independently with the area and internal density of focal adhesions, but not with their age or shape. Artificial neural network analysis indicates that a joint consideration of multiple components improves the predictability of paxillin and zyxin levels in internally dense focal adhesions. This suggests that paxillin and zyxin densities in focal adhesions are fine-tuned by integrating the levels of multiple other components, thus averaging-out stochastic fluctuations. Based on these results we propose that increase in internal protein densities facilitates noise suppression in focal adhesions, while noise suppression enables their stable growth and further density increase-hence forming a feedback loop giving rise to a quality-controlled assembly. PMID:27519053

  7. Highly Multiplexed Imaging Uncovers Changes in Compositional Noise within Assembling Focal Adhesions

    PubMed Central

    Harizanova, Jana; Fermin, Yessica; Malik-Sheriff, Rahuman S.; Wieczorek, Jakob; Ickstadt, Katja; Grecco, Hernán E.; Zamir, Eli

    2016-01-01

    Integrin adhesome proteins bind each other in alternative manners, forming within the cell diverse cell-matrix adhesion sites with distinct properties. An intriguing question is how such modular assembly of adhesion sites is achieved correctly solely by self-organization of their components. Here we address this question using high-throughput multiplexed imaging of eight proteins and two phosphorylation sites in a large number of single focal adhesions. We found that during the assembly of focal adhesions the variances of protein densities decrease while the correlations between them increase, suggesting reduction in the noise levels within these structures. These changes correlate independently with the area and internal density of focal adhesions, but not with their age or shape. Artificial neural network analysis indicates that a joint consideration of multiple components improves the predictability of paxillin and zyxin levels in internally dense focal adhesions. This suggests that paxillin and zyxin densities in focal adhesions are fine-tuned by integrating the levels of multiple other components, thus averaging-out stochastic fluctuations. Based on these results we propose that increase in internal protein densities facilitates noise suppression in focal adhesions, while noise suppression enables their stable growth and further density increase—hence forming a feedback loop giving rise to a quality-controlled assembly. PMID:27519053

  8. Phosphonic Acid-Functionalized Polyurethane Dispersions with Improved Adhesion Properties.

    PubMed

    Breucker, Laura; Landfester, Katharina; Taden, Andreas

    2015-11-11

    A facile route to phosphorus-functionalized polyurethane dispersions (P-PUDs) with improved adhesion properties is presented. (Bis)phosphonic acid moieties serve as adhesion promoting sites that are covalently attached via an end-capping reaction to isocyanate-reactive polyurethane particles under aqueous conditions. The synthetic approach circumvents solubility issues, offers great flexibility in terms of polyurethane composition, and allows for the synthesis of semicrystalline systems with thermomechanical response due to reversible physical cross-linking. Differential scanning calorimetry (DSC) is used to investigate the effect of functionalization on the semicrystallinity. The end-capping conversion was determined via inductively-coupled plasma optical emission spectroscopy (ICP-OES) and was surprisingly found to be almost independent of the stoichiometry of reaction, suggesting an adsorption-dominated process. Particle charge detection (PCD) experiments reveal that a dense surface coverage of phosphonic acid groups can be attained and that, at high functionalization degrees, the phosphonic adhesion moieties are partially dragged inside the colloidal P-PUD particle. Quartz crystal microbalance with dissipation (QCMD) investigations conducted with hydroxyapatite (HAP) and stainless steel sensors as model surfaces show a greatly enhanced affinity of the aqueous P-PUDs and furthermore indicate polymer chain rearrangements and autonomous film formation under wet conditions. Due to their facile synthesis, significantly improved adhesion, and variable film properties, P-PUD systems such as the one described here are believed to be of great interest for multiple applications, e.g., adhesives, paints, anticorrosion, or dentistry. PMID:26491881

  9. Adhesion and Fusion of Muscle Cells Are Promoted by Filopodia.

    PubMed

    Segal, Dagan; Dhanyasi, Nagaraju; Schejter, Eyal D; Shilo, Ben-Zion

    2016-08-01

    Indirect flight muscles (IFMs) in Drosophila are generated during pupariation by fusion of hundreds of myoblasts with larval muscle templates (myotubes). Live observation of these muscles during the fusion process revealed multiple long actin-based protrusions that emanate from the myotube surface and require Enabled and IRSp53 for their generation and maintenance. Fusion is blocked when formation of these filopodia is compromised. While filopodia are not required for the signaling process underlying critical myoblast cell-fate changes prior to fusion, myotube-myoblast adhesion appears to be filopodia dependent. Without filopodia, close apposition between the cell membranes is not achieved, the cell-adhesion molecule Duf is not recruited to the myotube surface, and adhesion-dependent actin foci do not form. We therefore propose that the filopodia are necessary to prime the heterotypic adhesion process between the two cell types, possibly by recruiting the cell-adhesion molecule Sns to discrete patches on the myoblast cell surface. PMID:27505416

  10. Optimizing Adhesive Design by Understanding Compliance.

    PubMed

    King, Daniel R; Crosby, Alfred J

    2015-12-23

    Adhesives have long been designed around a trade-off between adhesive strength and releasability. Geckos are of interest because they are the largest organisms which are able to climb utilizing adhesive toepads, yet can controllably release from surfaces and perform this action over and over again. Attempting to replicate the hierarchical, nanoscopic features which cover their toepads has been the primary focus of the adhesives field until recently. A new approach based on a scaling relation which states that reversible adhesive force capacity scales with (A/C)(1/2), where A is the area of contact and C is the compliance of the adhesive, has enabled the creation of high strength, reversible adhesives without requiring high aspect ratio, fibrillar features. Here we introduce an equation to calculate the compliance of adhesives, and utilize this equation to predict the shear adhesive force capacity of the adhesive based on the material components and geometric properties. Using this equation, we have investigated important geometric parameters which control force capacity and have shown that by controlling adhesive shape, adhesive force capacity can be increased by over 50% without varying pad size. Furthermore, we have demonstrated that compliance of the adhesive far from the interface still influences shear adhesive force capacity. Utilizing this equation will allow for the production of adhesives which are optimized for specific applications in commercial and industrial settings. PMID:26618537

  11. Endothelial cell adhesion in real time. Measurements in vitro by tandem scanning confocal image analysis.

    PubMed

    Davies, P F; Robotewskyj, A; Griem, M L

    1993-06-01

    Real time measurements of cell-substratum adhesion in endothelial cells were obtained by tandem scanning confocal microscopy of sites of focal contact (focal adhesions) at the abluminal cell surface. Focal contact sites were sharply defined (low radiance levels) in the living cell such that the images could be enhanced, digitized, and isolated from other cellular detail. Sites of focal contact are the principal determinant of cell-substratum adhesion. Measurements of (a) the focal contact area and (b) the closeness of contact (inverse radiance) were used to nominally define the adhesion of a single cell or field of cells, and to record spontaneous and induced changes of cell adhesion in real time. The topography of focal contacts was estimated by calculating separation distances from radiance values using a calibration technique based on interference ring optics. While slightly closer contact was noted between the cell membrane and substratum at or near the center of each focal contact, separation distances throughout the adhesion regions were always < 50 nm. Subtraction of consecutive images revealed continuous spontaneous remodeling of individual focal adhesions in unperturbed cells during periods of < 1 min. Despite extensive remodeling of focal contact sites, however, cell adhesion calculated for an entire cell over extended periods varied by < 10%. When cytoskeletal stability was impaired by exposure to cytochalasin or when cells were exposed to proteolytic enzyme, endothelial adhesion declined rapidly. Such changes were recorded at the level of single cells, groups of cells, and at single focal adhesions. In both unperturbed and manipulated cells, the dynamics of remodeling and cell adhesion characteristics varied greatly between individual sites within the same cell; disappearance of existing sites and appearance of new ones often occurred within minutes while adjacent sites underwent minimal remodelling. Tandem scanning confocal microscopy image analysis of

  12. Innovative Electrostatic Adhesion Technologies

    NASA Technical Reports Server (NTRS)

    Bryan, Tom; Macleod, Todd; Gagliano, Larry; Williams, Scott; McCoy, Brian

    2015-01-01

    Developing specialized Electro-Static grippers (commercially used in Semiconductor Manufacturing and in package handling) will allow gentle and secure Capture, Soft Docking, and Handling of a wide variety of materials and shapes (such as upper-stages, satellites, arrays, and possibly asteroids) without requiring physical features or cavities for a pincher or probe or using harpoons or nets. Combined with new rigid boom mechanisms or small agile chaser vehicles, flexible, high speed Electro-Static Grippers can enable compliant capture of spinning objects starting from a safe stand-off distance. Electroadhesion (EA) can enable lightweight, ultra-low-power, compliant attachment in space by using an electrostatic force to adhere similar and dissimilar surfaces. A typical EA enabled device is composed of compliant space-rated materials, such as copper-clad polyimide encapsulated by polymers. Attachment is induced by strong electrostatic forces between any substrate material, such as an exterior satellite panel and a compliant EA gripper pad surface. When alternate positive and negative charges are induced in adjacent planar electrodes in an EA surface, the electric fields set up opposite charges on the substrate and cause an electrostatic adhesion between the electrodes and the induced charges on the substrate. Since the electrodes and the polymer are compliant and can conform to uneven or rough surfaces, the electrodes can remain intimately close to the entire surface, enabling high clamping pressures. Clamping pressures of more than 3 N/cm2 in shear can be achieved on a variety of substrates with ultra-low holding power consumption (measured values are less than 20 microW/Newton weight held). A single EA surface geometry can be used to clamp both dielectric and conductive substrates, with slightly different physical mechanisms. Furthermore EA clamping requires no normal force be placed on the substrate, as conventional docking requires. Internally funded research and

  13. Innovative Electrostatic Adhesion Technologies

    NASA Astrophysics Data System (ADS)

    Gagliano, L.; Bryan, T.; Williams, S.; McCoy, B.; MacLeod, T.

    Developing specialized Electro-Static grippers (commercially used in Semiconductor Manufacturing and in package handling) will allow gentle and secure Capture, Soft Docking, and Handling of a wide variety of materials and shapes (such as upper-stages, satellites, arrays, and possibly asteroids) without requiring physical features or cavities for a pincher or probe or using harpoons or nets. Combined with new rigid boom mechanisms or small agile chaser vehicles, flexible, high speed Electro-Static Grippers can enable compliant capture of spinning objects starting from a safe stand-off distance. Electroadhesion (EA) can enable lightweight, ultra-low-power, compliant attachment in space by using an electrostatic force to adhere similar and dissimilar surfaces. A typical EA enabled device is composed of compliant space-rated materials, such as copper-clad polyimide encapsulated by polymers. Attachment is induced by strong electrostatic forces between any substrate material, such as an exterior satellite panel and a compliant EA surface. When alternate positive and negative charges are induced in adjacent planar electrodes in an EA surface, the electric fields set up opposite charges on the substrate and cause an electrostatic adhesion between the electrodes and the induced charges on the substrate. Since the electrodes and the polymer are compliant and can conform to uneven or rough surfaces, the electrodes can remain intimately close to the entire surface, enabling high clamping pressures. Clamping pressures of more than 3 N/cm2 in shear can be achieved on a variety of substrates with ultra-low holding power consumption (measured values are less than 20 microW/Newton weight held). A single EA surface geometry can be used to clamp both dielectric and conductive substrates, with slightly different physical mechanisms. Furthermore EA clamping requires no normal force be placed on the substrate, as conventional docking requires. Internally funded research and development

  14. Elastocapilllarity in insect adhesion: the case of beetle adhesive hair

    NASA Astrophysics Data System (ADS)

    Gernay, Sophie; Gilet, Tristan; Lambert, Pierre; Federle, Walter

    2014-11-01

    The feet of many insects are covered with dense arrays of hair-like structures called setae. Liquid capillary bridges at the tip of these micrometric structures are responsible for the controlled adhesion of the insect on a large variety of substrates. The resulting adhesion force can exceed several times the body weight of the insect. The high aspect-ratio of setae suggests that flexibility is a key ingredient in this capillary-based adhesion mechanism. There is indeed a strong coupling between their elastic deformation and the shape of the liquid meniscus. In this experimental work, we observe and quantify the local deflection of dock beetle seta tips under perpendicular loading using interference microscopy. Our results are then interpreted in the light of an analytic model of elastocapillarity. This research has been funded by the FRIA/FNRS and the Interuniversity Attraction Poles Programme (IAP 7/38 MicroMAST) initiated by the Belgian Science Policy Office.

  15. The neural cell adhesion molecule (NCAM) heparin binding domain binds to cell surface heparan sulfate proteoglycans.

    PubMed

    Kallapur, S G; Akeson, R A

    1992-12-01

    The neural cell adhesion molecule (NCAM) has been strongly implicated in several aspects of neural development. NCAM mediated adhesion has been proposed to involve a homophilic interaction between NCAMs on adjacent cells. The heparin binding domain (HBD) is an amino acid sequence within NCAM and has been shown to be involved in NCAM mediated adhesion but the relationship of this domain to NCAM segments mediating homophilic adhesion has not been defined. In the present study, a synthetic peptide corresponding to the HBD has been used as a substrate to determine its role in NCAM mediated adhesion. A neural cell line expressing NCAM (B35) and its derived clone which does not express NCAM (B35 clone 3) adhered similarly to plates coated with HBD peptide. A polyclonal antiserum to NCAM inhibited B35 cell-HBD peptide adhesion by only 10%, a value not statistically different from inhibition caused by preimmune serum. Both these experiments suggested no direct NCAM-HBD interactions. To test whether the HBD peptide bound to cell surface heparan sulfate proteoglycans (HSPG), HSPG synthesis was inhibited using beta-D-xyloside. After treatment, B35 cell adhesion to the HBD peptide, but not to control substrates, was significantly decreased. B35 cell adhesion to the HBD peptide could be inhibited by 10(-7) M heparin but not chondroitin sulfate. Preincubation of the substrate (HBD peptide) with heparin caused dramatic reduction of B35 cell-HBD peptide adhesion whereas preincubation of B35 cells with heparin caused only modest reductions in cell-HBD adhesion. Furthermore, inhibition of HSPG sulfation with sodium chlorate also decreased the adhesion of B35 cells to the HBD peptide. These results strongly suggest that, within the assay system, the NCAM HBD does not participate in homophilic interactions but binds to cell surface heparan sulfate proteoglycan. This interaction potentially represents an important mechanism of NCAM adhesion and further supports the view that NCAM has

  16. Consecutive successful pregnancies subsequent to intravenous immunoglobulin therapy in a patient with recurrent spontaneous miscarriage

    PubMed Central

    Diejomaoh, Michael F; Bello, Zainab; Al Jassar, Waleed; Jirous, Jiri; Karunakaran, Kavitha; Mohammed, Asiya T

    2015-01-01

    . The mother and baby made satisfactory progress and were discharged on January 24, 2015. Conclusion Two consecutive successful pregnancies in Mrs HM with multiple causes of RSM treated with other medications and IVIG strongly suggest that IVIG has a positive role in RSM. PMID:26715864

  17. High performance Cu adhesion coating

    SciTech Connect

    Lee, K.W.; Viehbeck, A.; Chen, W.R.; Ree, M.

    1996-12-31

    Poly(arylene ether benzimidazole) (PAEBI) is a high performance thermoplastic polymer with imidazole functional groups forming the polymer backbone structure. It is proposed that upon coating PAEBI onto a copper surface the imidazole groups of PAEBI form a bond with or chelate to the copper surface resulting in strong adhesion between the copper and polymer. Adhesion of PAEBI to other polymers such as poly(biphenyl dianhydride-p-phenylene diamine) (BPDA-PDA) polyimide is also quite good and stable. The resulting locus of failure as studied by XPS and IR indicates that PAEBI gives strong cohesive adhesion to copper. Due to its good adhesion and mechanical properties, PAEBI can be used in fabricating thin film semiconductor packages such as multichip module dielectric (MCM-D) structures. In these applications, a thin PAEBI coating is applied directly to a wiring layer for enhancing adhesion to both the copper wiring and the polymer dielectric surface. In addition, a thin layer of PAEBI can also function as a protection layer for the copper wiring, eliminating the need for Cr or Ni barrier metallurgies and thus significantly reducing the number of process steps.

  18. Flexible backbone aromatic polyimide adhesives

    NASA Technical Reports Server (NTRS)

    Progar, Donald J.; St.clair, Terry L.

    1988-01-01

    Continuing research at Langley Research Center on the synthesis and development of new inexpensive flexible aromatic polyimides as adhesives has resulted in a material identified as LARC-F-SO2 with similarities to polyimidesulfone, PISO2, and other flexible backbone polyimides recently reported by Progar and St. Clair. Also prepared and evaluated was an endcapped version of PISO2. These two polymers were compared with LARC-TPI and LARC-STPI, polyimides research in our laboratory and reported in the literature. The adhesive evaluation, primarily based on lap shear strength (LSS) tests at RT, 177 C and 204 C, involved preparing adhesive tapes, conducting bonding studies and exposing lap shear specimens to 204 C air for up to 1000 hrs and to a 72-hour water boil. The type of adhesive failure as well as the Tg was determined for the fractured specimens. The results indicate that LARC-TPI provides the highest LSSs. LARC-F-SO2, LARC-TPI and LARC-STPI all retain their strengths after thermal exposure for 1000 hrs and PISO2 retains greater than 80 percent of its control strengths. After a 72-hr water boil exposure, most of the four adhesive systems showed reduced strengths for all test temperatures although still retaining a high percentage of their original strength (greater than 60 percent) except for one case. The predominant failure type was cohesive with no significant change in the Tgs.

  19. Flexible backbone aromatic polyimide adhesives

    NASA Technical Reports Server (NTRS)

    Progar, Donald J.; St. Clair, Terry L.

    1989-01-01

    Continuing research at Langley Research Center on the synthesis and development of new inexpensive flexible aromatic polyimides as adhesives has resulted in a material identified as LARC-F-SO2 with similarities to polyimidesulfone, PISO2, and other flexible backbone polyimides recently reported by Progar and St. Clair. Also prepared and evaluated was an endcapped version of PISO2. These two polymers were compared with LARC-TPI and LARC-STPI, polyimides research in our laboratory and reported in the literature. The adhesive evaluation, primarily based on lap shear strength (LSS) tests at RT, 177 C and 204 C, involved preparing adhesive tapes, conducting bonding studies and exposing lap shear specimens to 204 C air for up to 1000 hrs and to a 72-hour water boil. The type of adhesive failure as well as the Tg was determined for the fractured specimens. The results indicate that LARC-TPI provides the highest LSSs. LARC-F-SO2, LARC-TPI and LARC-STPI all retain their strengths after thermal exposure for 1000 hrs and PISO2 retains greater than 80 percent of its control strengths. After a 72-hr water boil exposure, most of the four adhesive systems showed reduced strengths for all test temperatures although still retaining a high percentage of their original strength (greater than 60 percent) except for one case. The predominant failure type was cohesive with no significant change in the Tgs.

  20. Capillarity-based switchable adhesion

    PubMed Central

    Vogel, Michael J.; Steen, Paul H.

    2010-01-01

    Drawing inspiration from the adhesion abilities of a leaf beetle found in nature, we have engineered a switchable adhesion device. The device combines two concepts: The surface tension force from a large number of small liquid bridges can be significant (capillarity-based adhesion) and these contacts can be quickly made or broken with electronic control (switchable). The device grabs or releases a substrate in a fraction of a second via a low-voltage pulse that drives electroosmotic flow. Energy consumption is minimal because both the grabbed and released states are stable equilibria that persist with no energy added to the system. Notably, the device maintains the integrity of an array of hundreds to thousands of distinct interfaces during active reconfiguration from droplets to bridges and back, despite the natural tendency of the liquid toward coalescence. We demonstrate the scaling of adhesion strength with the inverse of liquid contact size. This suggests that strengths approaching those of permanent bonding adhesives are possible as feature size is scaled down. In addition, controllability is fast and efficient because the attachment time and required voltage also scale down favorably. The device features compact size, no solid moving parts, and is made of common materials. PMID:20133725

  1. Laboratory evaluation of adhesive systems.

    PubMed

    Barkmeier, W W; Cooley, R L

    1992-01-01

    Adhesive bonding of resin materials to acid-conditioned enamel is a clinically proven technique in preventative, restorative, and orthodontic procedures. Laboratory evaluations of etched-enamel resin bonding have shown excellent bond strengths and the virtual elimination of marginal microleakage. Adhesion to dentin has been more of a challenge. Earlier-generation dentin bonding systems did not yield high bond strengths in the laboratory or prevent marginal microleakage. Newer-generation adhesive systems generally use a dentin conditioner to modify or remove the smear layer and a subsequent application of an adhesive resin bonding agent. Laboratory evaluations of newer systems have shown bond strengths that approach or actually exceed that of etched enamel resin bonding. Bond strengths have improved with the evolution of dentin bonding systems, and microleakage from the cementum/dentin margin has been significantly reduced or prevented with the newer systems. Although laboratory testing of adhesive systems provides a mechanism to screen and compare newly developed systems, clinical trials are essential to document long-term clinical performance. PMID:1470553

  2. Semen characteristics in consecutive ejaculates with short abstinence in subfertile males.

    PubMed

    Bahadur, G; Almossawi, O; Zeirideen Zaid, R; Ilahibuccus, A; Al-Habib, A; Muneer, A; Okolo, S

    2016-03-01

    This study reports the favourable semen characteristics of 73 subfertile oligozoospermic men with short abstinence periods up to 40 min. Semen characteristics were compared between initial and consecutive ejaculate showing improved semen parameters: progressive grade A spermatozoa, morphology and sperm concentration. Median concentrations in initial and consecutive ejaculates were 10 million/ml and 17 million/ml, respectively. The second sample had a higher median normal morphology (7% versus 6%, P < 0.001). The median of non-progressive spermatozoa (Grade C) was significantly lower in the consecutive sample than the initial sample (0% versus 5%, P < 0.01). Medians for slow progression spermatozoa (B grade) and immotile spermatozoa (D grade) were lower in the consecutive samples (20% versus 13%, P < 0.01 and 60% versus 50%, P < 0.001, respectively). The median for rapid motility (Grade A) was significantly higher in the consecutive sample than the first (30% versus 5%, P < 0.001). Overall median progressive motility as benchmarked by the WHO 2010 criteria was significantly higher in the consecutive sample (43% versus 25%, P < 0.001). Semen analyses of consecutive semen samples collected 30 min (mean) apart in oligozoospemic men should be checked routinely for diagnostic purposes and for managing potential subfertility treatment. PMID:26776821

  3. UV curable pressure sensitive adhesives

    SciTech Connect

    Glotfelter, C.A.

    1995-12-01

    Pressure sensitive adhesives (PSA`s) have become a ubiquitous element in our society, so much so, that the relative status of a society can be determined by the per capita consumption of PSA`s. We discuss new monomers as components of PSA formulations which enable adhesion to be achieved on a variety of substrates. Since solventless coating systems are desirable, the UV PSA market is of utmost importance to meeting the strict environmental guidelines now being imposed worldwide. In addition, highly ethoxylated monomers have shown promise in water dispersed PSA formulations, and a self-emulsifying acrylate monomer has been developed to offer dispersive abilities without using traditional emulsifying agents. This talk will focus on the effects of the materials described on properties of adhesive strength and shear strength in UV PSA formulations.

  4. A novel addition polyimide adhesive

    NASA Technical Reports Server (NTRS)

    St.clair, T. L.; Progar, D. J.

    1981-01-01

    An addition polyimide adhesive, LARC 13, was developed which shows promise for bonding both titanium and composites for applications which require service temperatures in excess of 533 K. The LARC 13 is based on an oligomeric bis nadimide containing a meta linked aromatic diamine. The adhesive melts prior to polymerization due to its oligomeric nature, thereby allowing it to be processed at 344 kPa or less. Therefore, LARC 13 is ideal for the bonding of honeycomb sandwich structures. After melting, the resin thermosets during the cure of the nadic endcaps to a highly crosslinked system. Few volatiles are evolved, thus allowing large enclosed structures to be bonded. Preparation of the adhesive as well as bonding, aging, and testing of lap shear and honeycomb samples are discussed.

  5. Liposome adhesion generates traction stress

    NASA Astrophysics Data System (ADS)

    Murrell, Michael P.; Voituriez, Raphaël; Joanny, Jean-François; Nassoy, Pierre; Sykes, Cécile; Gardel, Margaret L.

    2014-02-01

    Mechanical forces generated by cells modulate global shape changes required for essential life processes, such as polarization, division and spreading. Although the contribution of the cytoskeleton to cellular force generation is widely recognized, the role of the membrane is considered to be restricted to passively transmitting forces. Therefore, the mechanisms by which the membrane can directly contribute to cell tension are overlooked and poorly understood. To address this, we directly measure the stresses generated during liposome adhesion. We find that liposome spreading generates large traction stresses on compliant substrates. These stresses can be understood as the equilibration of internal, hydrostatic pressures generated by the enhanced membrane tension built up during adhesion. These results underscore the role of membranes in the generation of mechanical stresses on cellular length scales and that the modulation of hydrostatic pressure due to membrane tension and adhesion can be channelled to perform mechanical work on the environment.

  6. Interfacial adhesion - Theory and experiment

    NASA Technical Reports Server (NTRS)

    Ferrante, John; Banerjea, Amitava; Bozzolo, Guillermo H.; Finley, Clarence W.

    1988-01-01

    Adhesion, the binding of different materials at an interface, is of general interest to many branches of technology, e.g., microelectronics, tribology, manufacturing, construction, etc. However, there is a lack of fundamental understanding of such diverse interfaces. In addition, experimental techniques generally have practical objectives, such as the achievement of sufficient strength to sustain mechanical or thermal effects and/or have the proper electronic properties. In addition, the theoretical description of binding at interfaces is quite limited, and a proper data base for such theoretical analysis does not exist. This presentation will review both experimental and theoretical aspects of adhesion in nonpolymer materials. The objective will be to delineate the critical parameters needed, governing adhesion testing along with an outline of testing objectives. A distinction will be made between practical and fundamental objectives. Examples are given where interfacial bonding may govern experimental consideration. The present status of theory is presented along with recommendations for future progress and needs.

  7. Interfacial adhesion: Theory and experiment

    NASA Technical Reports Server (NTRS)

    Ferrante, John; Bozzolo, Guillermo H.; Finley, Clarence W.; Banerjea, Amitava

    1988-01-01

    Adhesion, the binding of different materials at an interface, is of general interest to many branches of technology, e.g., microelectronics, tribology, manufacturing, construction, etc. However, there is a lack of fundamental understanding of such diverse interfaces. In addition, experimental techniques generally have practical objectives, such as the achievement of sufficient strength to sustain mechanical or thermal effects and/or have the proper electronic properties. In addition, the theoretical description of binding at interfaces is quite limited, and a proper data base for such theoretical analysis does not exist. This presentation will review both experimental and theoretical aspects of adhesion in nonpolymer materials. The objective will be to delineate the critical parameters needed, governing adhesion testing along with an outline of testing objectives. A distinction will be made between practical and fundamental objectives. Examples are given where interfacial bonding may govern experimental consideration. The present status of theory is presented along wiith recommendations for future progress and needs.

  8. Two consecutive singleton pregnancies versus one twins pregnancy as preferred outcome of in vitro fertilization for mothers and infants: a retrospective case-control study.

    PubMed

    La Sala, Giovanni Battista; Morini, Daria; Gizzo, Salvatore; Nicoli, Alessia; Palomba, Stefano

    2016-04-01

    Objective Many infertile couples request a multiple embryo transfer because they desire more than one child. Based on this consideration, the current study aimed to compare the reproductive and perinatal outcomes of two consecutive singleton pregnancies versus one twin pregnancy in a large cohort of in vitro fertilization (IVF) patients. Research design and methods Retrospective analysis of data from patients with clinical twin pregnancy after IVF fresh cycles and from patients with two consecutive IVF fresh cycles and clinical singleton pregnancy. Main outcome measures Miscarriage rate, delivery rate, gestational age at birth, neonatal birth weight, and perinatal complications. A sub-analysis of data according to vanishing twin syndrome (VTS) was also performed. Results A total of 18,703 autologous fresh cycles were analyzed. One hundred seven patients had two consecutive singleton clinical pregnancies, whereas one clinical twin pregnancy occurred in 641 women. In patients who had two consecutive singleton clinical pregnancies the rates of overall pregnancies lost (odds ratio [OR] 4.9, 95% confidence interval [CI] 3.4, 6.9) and live births (OR 0.2, 95% CI 0.1, 0.3) were, respectively, higher and lower when compared to patients who had one clinical twin pregnancy. That data did not change after sub-analysis for VTS. The overall risk of perinatal complications was significantly higher in patients who had one twin delivery rather than patients who had two consecutive singleton deliveries (OR 31.8, 95% CI 14.1, 71.5). No difference between groups was detected in terms of intrauterine/neonatal deaths, perinatal mortality and neonatal intensive care unit admission. Data did not change after adjusting for confounders. Conclusions When compared with two consecutive singleton pregnancies, twin pregnancies are characterized by higher success rates but worse perinatal outcomes irrespectively of VTS. Well designed prospective controlled studies are needed to confirm or rebut

  9. Does the use of a novel self-adhesive flowable composite reduce nanoleakage?

    PubMed Central

    Naga, Abeer Abo El; Yousef, Mohammed; Ramadan, Rasha; Fayez Bahgat, Sherif; Alshawwa, Lana

    2015-01-01

    Objective The aim of the study reported here was to evaluate the performance of a self-adhesive flowable composite and two self-etching adhesive systems, when subjected to cyclic loading, in preventing the nanoleakage of Class V restorations. Methods Wedge-shape Class V cavities were prepared (4×2×2 mm [length × width × depth]) on the buccal surfaces of 90 sound human premolars. Cavities were divided randomly into three groups (n=30) according to the used adhesive (Xeno® V [self-etching adhesive system]) and BOND-1® SF (solvent-free self-etching adhesive system) in conjunction with Artiste® Nano Composite resin, and Fusio™ Liquid Dentin (self-adhesive flowable composite), consecutively. Each group was further divided into three subgroups (n=10): (A) control, (B) subjected to occlusal cyclic loading (90N for 5,000 cycles), and (C) subjected to occlusal cyclic loading (90N for 10,000 cycles). Teeth then were coated with nail polish up to 1 mm from the interface, immersed in 50% silver nitrate solution for 24 hours and tested for nanoleakage using the environmental scanning electron microscopy and energy dispersive analysis X-ray analysis. Data were statistically analyzed using two-way analysis of variance and Tukey’s post hoc tests (P≤0.05). Results The Fusio Liquid Dentin group showed statistically significant lower percentages of silver penetration (0.55 μ) compared with the BOND-1 SF (3.45 μ) and Xeno V (3.82 μ) groups, which were not statistically different from each other, as they both showed higher silver penetration. Conclusion Under the test conditions, the self-adhesive flowable composite provided better sealing ability. Aging of the two tested adhesive systems, as a function of cyclic loading, increased nanoleakage. PMID:25848318

  10. Dual-Mode Adhesive Pad

    NASA Technical Reports Server (NTRS)

    Hartz, Leslie

    1994-01-01

    Tool helps worker grip and move along large, smooth structure with no handgrips or footholds. Adheres to surface but easily released by actuating simple mechanism. Includes handle and segmented contact-adhesive pad. Bulk of pad made of soft plastic foam conforming to surface of structure. Each segment reinforced with rib. In sticking mode, ribs braced by side catches. In peeling mode, side catches retracted, and segmented adhesive pad loses its stiffness. Modified versions useful in inspecting hulls of ships and scaling walls in rescue operations.

  11. Adhesive, elastomeric gel impregnating composition

    DOEpatents

    Shaw, David Glenn; Pollard, John Randolph; Brooks, Robert Aubrey

    2002-01-01

    An improved capacitor roll with alternating film and foil layers is impregnated with an adhesive, elastomeric gel composition. The gel composition is a blend of a plasticizer, a polyol, a maleic anhydride that reacts with the polyol to form a polyester, and a catalyst for the reaction. The impregnant composition is introduced to the film and foil layers while still in a liquid form and then pressure is applied to aid with impregnation. The impregnant composition is cured to form the adhesive, elastomeric gel. Pressure is maintained during curing.

  12. Biliary reconstructions and complications encountered in 50 consecutive right-lobe living donor liver transplantations.

    PubMed

    Icoz, Gokhan; Kilic, Murat; Zeytunlu, Murat; Celebi, Arzu; Ersoz, Galip; Killi, Refik; Memis, Ahmet; Karasu, Zeki; Yuzer, Yildiray; Tokat, Yaman

    2003-06-01

    Biliary complications appear to be the leading cause of postoperative complications after living donor liver transplantation (LDLT). The aim of this study is to analyze the complications, treatment modalities, and outcomes of biliary anastomoses in a series of 50 consecutive right-lobe LDLTs. Median patient age was 45 years, and median right-lobe graft volume was 740 g. Graft-recipient weight ratio was 0.69 to 1.80. Median follow-up time was 15 months (range, 2 to 38 months). Eleven of 50 patients died, resulting in an overall allograft and patient survival rate of 78%. In biliary reconstruction, a duct-to-duct (D-D) anastomosis or a standard Roux-en-Y (R-Y) anastomosis was performed. Twenty-nine grafts (58%) had a single duct for anastomosis. Seventeen grafts (34%) had two bile duct orifices, and four grafts (8%) had three bile duct orifices. A D-D anastomosis was performed in 36 cases (72%), whereas R-Y reconstruction was preferred in 14 cases (28%). The overall incidence of biliary anastomotic complications was 30% in this series. Five patients developed biliary leaks, presumably from the cut surface, and all of them healed spontaneously. Two bilomas were drained percutaneously. Anastomotic strictures occurred in 8 patients (16%) and were significantly greater than in the R-Y group (P =.03). Although strictures seemed to develop more frequently in allografts with multiple bile ducts, this did not reach statistical significance (P =.05). All strictures were managed by nonsurgical measures initially. Restenosis occurred in 2 patients, both of whom had an R-Y anastomotic stricture. These anastomoses were revised surgically, giving a reoperation rate of 4% for biliary problems. No graft or patient was lost because of biliary problems. Our data suggest that D-D anastomosis is a safe and feasible method of biliary reconstruction in LDLT by preserving physiological bilioenteric continuity and allowing easy access through endoscopic techniques. PMID:12783398

  13. Effect of polyacrylamide as a post-fire erosion mitigation treatment during consecutive rainstorms

    NASA Astrophysics Data System (ADS)

    Inbar, Assaf; Ben-Hur, Meni; Sternberg, Marcelo; Liñares, Marcos

    2014-05-01

    Anionic polyacrylamide (PAM) has been proven to be an effective chemical soil amendment for reducing erosion in arable lands and infrastructure projects, but few attempts have been made to use it as a post-fire mitigation measure. Moreover, the mechanisms by which PAM reduces soil erosion are not fully understood. In this study, we tested the use of 50 kg/ha granular PAM as a post-fire amendment on infiltration rate (IR), runoff and soil loss both in laboratory and field experiments involving multiple rainstorms. In the laboratory experiments, three consecutive storms separated by drying periods were applied by means of a rainfall simulator to two contrasting soils affected by fire (Humic Cambisol and Calcic Regosol). During the 1st rainstorm, PAM decreased IR and increased runoff in both soils due to an increase in viscosity of the runoff and soil solution. At the same time, a reduction in soil loss was observed in both PAM-treated soils compared to the untreated controls. During the first drying period, PAM was irreversibly adsorbed to soil particles, and in the following storms PAM-induced soil loss reduction persisted while the effect of the polymer on IR and runoff was reversed. Differences in the effect of PAM on soil erosion between soils were attributed to changes in the electrolyte concentration of runoff and soil solution. The positive effect of PAM on post-fire soil loss was confirmed in field experiments with erosion plots constructed in the burnt Calcic Regosol. The application of 25 and 50 kg/ha of granular PAM reduced soil erosion by 23 and 57%, respectively, compared to the untreated control. Runoff was reduced only in the 50 kg/ha treatment. It is suggested that the application of PAM could be a good alternative to current post-fire erosion mitigation measures.

  14. Tuberous sclerosis complex-associated renal angiomyolipomas: A single center study of 17 consecutive cases

    PubMed Central

    Wang, Hang; Long, Qilai; Wang, Yiwei; Liu, Li; Zhou, Lin; Guo, Jianming

    2016-01-01

    The aim of the present study was to investigate the treatment options for patients with tuberous sclerosis complex (TSC)-associated renal angiomyolipomas (AMLs). A total of 17 patients who were consecutively diagnosed with TSC-associated renal AMLs at the Department of Urology of Zhongshan Hospital between 1998 and 2012 were included in the study. The patient cohort included 7 males and 10 females with a mean age of 37.6 years (range, 18–62 years). A total of 12 patients were diagnosed with renal AML with TSC during physical examination (PE), while 5 patients were admitted to the Emergency Department of Zhongshan Hospital due to spontaneous rupture of renal AMLs. All renal lesions were examined by ultrasonography and abdominal computed tomography prior to treatment. The primary outcome measure was the kidney reservation rate (patients that had not received nephrectomies) in the rupture group and PE group. Both abdominal ultrasonography and CT revealed AMLs in all patients and the mean tumor size was 10.0±4.0 cm (range, 3.0–17.5 cm). Overall, 9 patients underwent surgery, which included unilateral nephrectomy in 4 patients and unilateral partial nephrectomy/tumor enucleation in 5 patients. The remaining 8 patients received medical treatment. All patients were followed-up for between 10 and 67 months. One patient succumbed as a result of multiple organ failure, which was caused by hypovolemic shock due to the spontaneous rupture of renal AML. The kidney reservation rate during surgery was 87.5% (7/8) in the PE group and 25% (1/4) in the spontaneous rupture group. The management of TSC-associated renal AMLs differs from that of solitary sporadic AMLs. Surgical therapy is recommended following careful risk-benefit analysis. PMID:27446460

  15. State of the art etch-and-rinse adhesives

    PubMed Central

    Pashley, David H; Tay, Franklin R; Breschi, Lorenzo; Tjäderhane, Leo; Carvalho, Ricardo M; Carrilho, Marcela; Tezvergil-Mutluay, Arzu

    2013-01-01

    Etch-and-rinse adhesive systems are the oldest of the multi-generation evolution of resin bonding systems. In the 3-step version, they involve acid-etching, priming and application of a separate adhesive. Each step can accomplish multiple goals. This review explores the therapeutic opportunities of each separate step. Acid-etching, using 32-37% phosphoric acid (pH 0.1-0.4) not only simultaneously etches enamel and dentin, but the low pH kills many residual bacteria. Some etchants include anti-microbial compounds such as benzalkonium chloride that also inhibits matrix metalloproteinases (MMPs) in dentin. Primers are usually water and HEMA-rich solutions that ensure complete expansion of the collagen fibril meshwork and wet the collagen with hydrophilic monomers. However, water alone can re-expand dried dentin and can also serve as a vehicle for protease inhibitors or protein cross-linking agents that may increase the durability of resin-dentin bonds. In the future, ethanol or other water-free solvents may serve as dehydrating primers that may also contain antibacterial quaternary ammonium methacrylates to inhibit dentin MMPs and increase the durability of resin-dentin bonds. The complete evaporation of solvents is nearly impossible. Manufacturers may need to optimize solvent concentrations. Solvent-free adhesives can seal resin-dentin interfaces with hydrophobic resins that may also contain fluoride and antimicrobial compounds. Etch-and-rinse adhesives produce higher resin-dentin bonds that are more durable than most 1 and 2-step adhesives. Incorporation of protease inhibitors in etchants and/or cross-linking agents in primers may increase the durability of resin-dentin bonds. The therapeutic potential of etch-and-rinse adhesives has yet to be fully exploited. PMID:21112620

  16. Photoresist substrate having robust adhesion

    DOEpatents

    Dentinger, Paul M.

    2005-07-26

    A substrate material for LIGA applications w hose general composition is Ti/Cu/Ti/SiO.sub.2. The SiO.sub.2 is preferably applied to the Ti/Cu/Ti wafer as a sputtered coating, typically about 100 nm thick. This substrate composition provides improved adhesion for epoxy-based photoresist materials, and particularly the photoresist material SU-8.

  17. Fluorescence Reveals Contamination From Adhesives

    NASA Technical Reports Server (NTRS)

    Nikolia, William

    1992-01-01

    Contamination of nearby surfaces from ingredients in some adhesive materials detected by ultraviolet illumination and observation of resulting fluorescence. Identification of contaminants via telltale fluorescence not new; rather, significance lies in method of implementation and potential extension to wider variety of materials and applications.

  18. Candida biofilms: is adhesion sexy?

    PubMed

    Soll, David R

    2008-08-26

    The development of Candida albicans biofilms requires two types of adhesion molecule - the Als proteins and Hwp1. Mutational analyses have recently revealed that these molecules play complementary roles, and their characteristics suggest that they may have evolved from primitive mating agglutinins. PMID:18727911

  19. Computational Chemistry of Adhesive Bonds

    NASA Technical Reports Server (NTRS)

    Phillips, Donald H.

    1999-01-01

    This investigation is intended to determine the electrical mechanical, and chemical properties of adhesive bonds at the molecular level. The initial determinations will be followed by investigations of the effects of environmental effects on the chemistry and properties of the bond layer.

  20. New adhesive withstands temperature extremes

    NASA Technical Reports Server (NTRS)

    Park, J. J.; Seidenberg, B.

    1978-01-01

    Adhesive, developed for high-temperature components aboard satellites, is useful at both high and low temperatures and exhibits low-vacuum volatility and low shrinkage. System uses polyfunctional epoxy with high aromatic content, low equivalent weight, and more compact polymer than conventional bisphenol A tape.

  1. Arthroscopic repair of acetabular chondral delamination with fibrin adhesive.

    PubMed

    Tzaveas, Alexandros P; Villar, Richard N

    2010-01-01

    Acetabular chondral delamination is a frequent finding at hip arthroscopy. The cartilage is macroscopically normal but disrupted from the subchondral bone. Excision of chondral flaps is the usual procedure for this type of lesion. However, we report 19 consecutive patients in whom the delaminated chondral flap was re-attached to the underlying subchondral bone with fibrin adhesive. We used the modified Harris hip score for assessment of pain and function. Improvement in pain and function was found to be statistically significant six months and one year after surgery. No local or general complications were noted. Three patients underwent further surgery for unrelated reasons. In each, the area of fibrin repair appeared intact and secure. Our results suggest that fibrin is a safe agent to use for acetabular chondral delamination. PMID:20235074

  2. Tackifier Dispersions to Make Pressure Sensitive Adhesives

    SciTech Connect

    2003-02-01

    Development of new processes for tackifier dispersion could improve the production of pressure sensitive adhesives. Pressure sensitive adhesives (PSAs) have the ability to adhere to different surfaces with manual or finger pressure.

  3. Microfluidic adhesion induced by subsurface microstructures.

    PubMed

    Majumder, Abhijit; Ghatak, Animangsu; Sharma, Ashutosh

    2007-10-12

    Natural adhesives in the feet of different arthropods and vertebrates show strong adhesion as well as excellent reusability. Whereas the hierarchical structures on the surface are known to have a substantial effect on adhesion, the role of subsurface structures such as the network of microchannels has not been studied. Inspired by these bioadhesives, we generated elastomeric layers with embedded air- or oil-filled microchannels. These adhesives showed remarkable enhancement of adhesion ( approximately 30 times), which results from the crack-arresting properties of the microchannels, together with the surface stresses caused by the capillary force. The importance of the thickness of the adhesive layer, channel diameter, interchannel spacing, and vertical position within the adhesive has been examined for developing an optimal design of this microfluidic adhesive. PMID:17932295

  4. Evaluation of the metal/adhesive interfaces in the MC2370 fire set

    SciTech Connect

    Zavadil, K.R.

    1997-10-01

    Several analysis methods have been applied to evaluate the structure and composition of the electrode/adhesive interfaces i previously fielded M2370 Fire Sets. A method of interfacial fracture at cryogenic temperatures as been employed to expose regions of these interfaces at multiple levels in a SFE stack. Electron microscopy shows that bond failure induced by the fracture is predominantly adhesive with an equal probability of failure of the Au and Cu interfaces. Some evidence for cohesive, indicative of a possible microstructure related to electrical breakdown. Pinhole-free larger regions of adhesive also exist which may explain the observed high resistance in impedance measurements.

  5. Alterations in cell adhesion proteins and cardiomyopathy

    PubMed Central

    Li, Jifen

    2014-01-01

    Cell adhesive junction is specialized intercellular structure composed of cell adhesion proteins. They are essential to connect adjacent heart muscle cell and make heart contraction effectively and properly. Clinical and genetic studies have revealed close relationship between cell adhesive proteins and the occurrence of various cardiomyopathies. Here we will review recent development on the disease phenotype, potential cellular and molecular mechanism related to cell adhesion molecules, with particular disease pathogenesis learned from genetic manipulated murine models. PMID:24944760

  6. 21 CFR 878.4380 - Drape adhesive.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Drape adhesive. 878.4380 Section 878.4380 Food and... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4380 Drape adhesive. (a) Identification. A drape adhesive is a device intended to be placed on the skin to attach a surgical drape....

  7. 21 CFR 878.4380 - Drape adhesive.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Drape adhesive. 878.4380 Section 878.4380 Food and... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4380 Drape adhesive. (a) Identification. A drape adhesive is a device intended to be placed on the skin to attach a surgical drape....

  8. 21 CFR 175.105 - Adhesives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Adhesives. 175.105 Section 175.105 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS OF COATINGS Substances for Use Only as Components of Adhesives §...

  9. 21 CFR 175.105 - Adhesives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Adhesives. 175.105 Section 175.105 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS OF COATINGS Substances for Use Only as Components of Adhesives §...

  10. Nonwoven glass fiber mat reinforces polyurethane adhesive

    NASA Technical Reports Server (NTRS)

    Roseland, L. M.

    1967-01-01

    Nonwoven glass fiber mat reinforces the adhesive properties of a polyurethane adhesive that fastens hardware to exterior surfaces of aluminum tanks. The mat is embedded in the uncured adhesive. It ensures good control of the bond line and increases the peel strength.