Sample records for factors affecting bond

  1. Bonding strategies for MIH-affected enamel and dentin.

    PubMed

    Krämer, Norbert; Bui Khac, Ngoc-Han Nana; Lücker, Susanne; Stachniss, Vitus; Frankenberger, Roland

    2018-02-01

    Aim of the present study was to evaluate resin composite adhesion to dental hard tissues affected by molar incisor hypomineralisation (MIH). 94 freshly extracted human molars and incisors (53 suffering MIH) were used. 68 teeth (35 with MIH) were used for μ-TBS tests in enamel and dentin, 26 (18 with MIH) for qualitative evaluation. Specimens were bonded with Clearfil SE Bond, Scotchbond Universal, and OptiBond FL. For MIH affected enamel, additional OptiBond FL groups with NaOCl and NaOCl+Icon were investigated. Beside fractographic analysis, also qualitative evaluations were performed using SEM at different magnifications as well as histological sectioning. Highest μ-TBS values were recorded with dentin specimens (ANOVA, mod. LSD, p<0.05). Results were independent of adhesive and dentin substrate (p>0.05). Pre-test failures did not occur in dentin specimens. Sound enamel specimens exhibited significantly higher μ-TBS values than MIH enamel (p<0.05). The two-step self-etch adhesive (Clearfil SE Bond) and the two-step etch-and-rinse adhesive (Scotchbond Universal) showed the lowest values in affected enamel specimens (p<0.05) with most pre-test failures (p<0.05). OptiBond FL on affected enamel showed better results than Clearfil SE Bond (p<0.05). An additional pre-treatment of affected enamel with NaOCl or NaOCl and Icon did not enhance enamel bonding (p>0.05), however, it caused less pre-test failures (p<0.05). Micromorphological analyses revealed that conventional phosphoric acid etching produces a much less pronounced etching pattern in affected enamel and a porous structure as weak link for the resin-enamel bond was identified. Bonding to porous hypomineralized MIH enamel is the limiting factor in adhesion to MIH teeth. MIH-affected dentin may be bonded conventionally. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  2. Factors affecting the shear bond strength of metal and ceramic brackets bonded to different ceramic surfaces.

    PubMed

    Abu Alhaija, Elham S J; Abu AlReesh, Issam A; AlWahadni, Ahed M S

    2010-06-01

    The aims of this study were to evaluate the shear bond strength (SBS) of metal and ceramic brackets bonded to two different all-ceramic crowns, IPS Empress 2 and In-Ceram Alumina, to compare the SBS between hydrofluoric acid (HFA), phosphoric acid etched, and sandblasted, non-etched all-ceramic surfaces. Ninety-six all-ceramic crowns were fabricated resembling a maxillary left first premolar. The crowns were divided into eight groups: (1) metal brackets bonded to sandblasted 9.6 per cent HFA-etched IPS Empress 2 crowns; (2) metal brackets bonded to sandblasted 9.6 per cent HFA-etched In-Ceram crowns; (3) ceramic brackets bonded to sandblasted 9.6 per cent HFA-etched IPS Empress 2 crowns; (4) ceramic brackets bonded to sandblasted 9.6 per cent HFA-etched In-Ceram crowns; (5) metal brackets bonded to sandblasted 37 per cent phosphoric acid-etched IPS Empress 2 crowns; (6) metal brackets bonded to sandblasted 37 per cent phosphoric acid-etched In-Ceram crowns; (7) metal brackets bonded to sandblasted, non-etched IPS Empress 2 crowns; and (8) metal brackets bonded to sandblasted, non-etched In-Ceram crowns. Metal and ceramic orthodontic brackets were bonded using a conventional light polymerizing adhesive resin. An Instron universal testing machine was used to determine the SBS at a crosshead speed of 0.1 mm/minute. Comparison between groups was performed using a univariate general linear model and chi-squared tests. The highest mean SBS was found in group 3 (120.15 +/- 45.05 N) and the lowest in group 8 (57.86 +/- 26.20 N). Of all the variables studied, surface treatment was the only factor that significantly affected SBS (P < 0.001). Acid etch application to sandblasted surfaces significantly increased the SBS in groups 1, 2, 5, and 6. The SBS of metal brackets debonded from groups 1, 3, and 5 were not significantly different from those of groups 2, 4, and 6. All debonded metal brackets revealed a similar pattern of bond failure at the adhesive-restorative interface

  3. Analysis of factors influencing the bond strength in roll bonding processes

    NASA Astrophysics Data System (ADS)

    Khaledi, Kavan; Wulfinghoff, Stephan; Reese, Stefanie

    2018-05-01

    Cold Roll Bonding (CRB) is recognized as an industrial technique in which the metal sheets are joined together in order to produce laminate metal composites. In this technique, a metallurgical bond resulting from severe plastic deformation is formed between the rolled metallic layers. The main objective of this paper is to analyse different factors which may affect the bond formation in rolling processes. To achieve this goal, first, an interface model is employed which describes both the bonding and debonding. In this model, the bond strength evolution between the metallic layers is calculated based on the film theory of bonding. On the other hand, the debonding process is modelled by means of a bilinear cohesive zone model. In the numerical section, different scenarios are taken into account to model the roll bonding process of metal sheets. The numerical simulation includes the modelling of joining during the roll bonding process followed by debonding in a Double Cantilever Beam (DCB) peeling test. In all simulations, the metallic layers are regarded as elastoplastic materials subjected to large plastic deformations. Finally, the effects of some important factors on the bond formation are numerically investigated.

  4. Effect of etching on bonding of a self-etch adhesive to dentine affected by amelogenesis imperfecta.

    PubMed

    Epasinghe, Don Jeevanie; Yiu, Cynthia Kar Yung

    2018-02-01

    Dentine affected by amelogenesis imperfecta (AI) is histologically altered due to loss of hypoplastic enamel and becomes hypermineralized. In the present study, we examined the effect of additional acid etching on microtensile bond strength of a self-etch adhesive to AI-affected dentine. Flat coronal dentine obtained from extracted AI-affected and non-carious permanent molars were allocated to two groups: (a) Clearfil SE Bond (control); and (b) Clearfil SE Bond and additional etching with 34% phosphoric acid for 15 seconds. The bonded teeth were sectioned into .8-mm 2 beams for microtensile bond strength testing, and stressed to failure under tension. The bond strength data were analyzed using two-way analysis of variance (dentine type and etching step) and Student-Newman-Keuls multiple comparison test (P<.05). Representative fractured beams from each group were examined under scanning electron microscopy. Both factors, dentine substrate (P<.001) and etching step (P<.05), and their interactions (P<.001), were statistically significant. Additional etching had an adverse effect on the bond strength of Clearfil SE Bond to normal dentine (P<.005), and no significant improvement was found for AI-affected dentine (P=.479). Additional acid etching does not improve the bond strength of a self-etch adhesive to AI-affected dentine. © 2017 John Wiley & Sons Australia, Ltd.

  5. Factors Affecting the Shear Bond Strength of Orthodontic Brackets - a Review of In Vitro Studies.

    PubMed

    Bakhadher, Waleed; Halawany, Hassan; Talic, Nabeel; Abraham, Nimmi; Jacob, Vimal

    2015-01-01

    The adhesive material used to bond orthodontic brackets to teeth should neither fail during the treatment period, resulting in treatment delays, untoward expenses or patient inconvenience nor should it damage the enamel on debonding at the end of the treatment. Although the effectiveness of a bonding system and any unfavorable effects on the enamel may be studied by conducting in-vivo studies, it is nearly impossible to independently analyze different variables that influence a specific bonding system in the oral environment. In-vitro studies, on the other hand, may utilize more standardized protocols for testing different bonding systems and materials available. Thus, the present review focused attention on in-vitro studies and made an attempt to discuss material-related, teeth-related (fluorotic vs non-fluorotic teeth) and other miscellaneous factors that influences the shear bond strength of orthodontic brackets. Within the limitations of this review, using conventional acid-etch technique, ceramic brackets and bonding to non-fluorotic teeth was reported to have a positive influence on the shear bond strength of orthodontic brackets, but higher shear bond strength found on using ceramic brackets can be dangerous for the enamel.

  6. Effects of Chemical Cross-linkers on Caries-affected Dentin Bonding

    PubMed Central

    Macedo, G.V.; Yamauchi, M.; Bedran-Russo, A.K.

    2009-01-01

    The achievement of a strong and stable bond between composite resin and dentin remains a challenge in restorative dentistry. Over the past two decades, dental materials have been substantially improved, with better handling and bonding characteristics. However, little attention has been paid to the contribution of collagen structure/stability to bond strength. We hypothesized that the induction of cross-linking in dentin collagen improves dentin collagen stability and bond strength. This study investigated the effects of glutaraldehyde- and grape seed extract-induced cross-linking on the dentin bond strengths of sound and caries-affected dentin, and on the stability of dentin collagen. Our results demonstrated that the application of chemical cross-linking agents to etched dentin prior to bonding procedures significantly enhanced the dentin bond strengths of caries-affected and sound dentin. Glutaraldehyde and grape seed extract significantly increased dentin collagen stability in sound and caries-affected dentin, likely via distinct mechanisms. PMID:19892915

  7. Bond strength of different adhesives to normal and caries-affected dentins.

    PubMed

    Xuan, Wei; Hou, Ben-xiang; Lü, Ya-lin

    2010-02-05

    Currently, several systems of dentin substrate-reacting adhesives are available for use in the restorative treatment against caries. However, the bond effectiveness and property of different adhesive systems to caries-affected dentin are not fully understood. The objective of this study was to evaluate the bond strength of different adhesives to both normal dentin (ND) and caries-affected dentin (CAD) and to analyze the dentin/adhesive interfacial characteristics. Twenty eight extracted human molars with coronal medium carious lesions were randomly assigned to four groups according to adhesives used. ND and CAD were bonded with etch-and-rinse adhesive Adper Single Bond 2 (SB2) or self-etching adhesives Clearfil SE Bond (CSE), Clearfil S(3) Bond (CS3), iBond GI (IB). Rectangular sticks of resin-dentin bonded interfaces 0.9 mm(2) were obtained. The specimens were subjected to microtensile bond strength (microTBS) testing at a crosshead speed of 1 mm/min. Mean microTBS was statistically analyzed with analysis of variance (ANOVA) and Student-Newman-Keuls tests. Interfacial morphologies were analyzed by Scanning Electron Microscopy (SEM). Etch-and-rinse adhesive Adper(TM) Single Bond 2 yielded high bond strength when applied to both normal and caries-affected dentin. The two-step self-etching adhesive Clearfil SE Bond generated the highest bond strength to ND among all adhesives tested but a significantly reduced strength when applied to CAD. For the one-step self-etching adhesives, Clearfil S(3) Bond and iBond GI, the bond strength was relatively low regardless of the dentin type. SEM interfacial analysis revealed that hybrid layers were thicker with poorer resin tag formation and less resin-filled lateral branches in the CAD than in the ND for all the adhesives tested. The etch-and-rinse adhesive performed more effectively to caries-affected dentin than the self-etching adhesives.

  8. Microtensile bond strength of three simplified adhesive systems to caries-affected dentin.

    PubMed

    Scholtanus, J D; Purwanta, Kenny; Dogan, Nilgun; Kleverlaan, Cees J; Feilzer, Albert J

    2010-08-01

    The purpose of the study was to determine the microtensile bond strength of three different simplified adhesive systems to caries-affected dentin. Fifteen extracted human molars with primary carious lesions were ground flat until dentin was exposed. Soft caries-infected dentin was excavated with the help of caries detector dye. On the remaining hard dentin, a standardized smear layer was created by polishing with 600-grit SiC paper. Teeth were divided into three groups and treated with one of the three tested adhesives: Adper Scotchbond 1 XT (3M ESPE), a 2-step etch-andrinse adhesive, Clearfil S3 Bond (Kuraray), a 1-step self-etching or all-in-one adhesive, and Clearfil SE Bond (Kuraray), a 2-step self-etching adhesive. Five-mm-thick composite buildups (Z-250, 3M ESPE) were built and light cured. After water storage for 24 h at 37ºC, the bonded specimens were sectioned into bars (1.0 x 1.0 mm; n = 20 to 30). Microtensile bond strength of normal dentin specimens and caries-affected dentin specimens was measured in a universal testing machine (crosshead speed = 1 mm/min). Data were analyzed using two-way ANOVA and Tukey's post-hoc test (p < 0.05). No significant differences in bond strength values to normal dentin between the three adhesives were found. Adper Scotchbond 1 XT and Clearfil S3 Bond showed significantly lower bond strength values to caries-affected dentin. For Clearfil SE Bond, bond strength values to normal and caries-affected dentin were not significantly different. All the tested simplified adhesives showed similar bond strength values to normal dentin. For the tested 2-step etch-and-rinse adhesive and the all-in-one adhesive, the bond strength values to caries-affected dentin were lower than to normal dentin.

  9. Dentin pretreatment and adhesive temperature as affecting factors on bond strength of a universal adhesive system.

    PubMed

    Sutil, Bruna Gabrielle da Silva; Susin, Alexandre Henrique

    2017-01-01

    To evaluate the effects of dentin pretreatment and temperature on the bond strength of a universal adhesive system to dentin. Ninety-six extracted non-carious human third molars were randomly divided into 12 groups (n=8) according to Scotchbond Universal Adhesive (SbU) applied in self-etch (SE) and etch-and-rinse (ER) mode, adhesive temperature (20°C or 37°C) and sodium bicarbonate or aluminum oxide air abrasion. After composite build up, bonded sticks with cross-sectional area of 1 mm2 were obtained to evaluate the microtensile bond strength (μTBS). The specimens were tested at a crosshead speed of 0.5 mm/min on a testing machine until failure. Fractured specimens were analyzed under stereomicroscope to determine the failure patterns in adhesive, cohesive (dentin or resin) and mixed fractures. The microtensile bond strength data was analyzed using two-way ANOVA and Tukey's test (α=5%). Interaction between treatment and temperature was statistically significant for SbU applied in self-etch technique. Both dentin treatments showed higher bond strength for ER mode, regardless of adhesive temperature. When compared to control group, sodium bicarbonate increased bond strength of SbU in SE technique. Adhesive temperature did not significantly affect the μTBS of tested groups. Predominantly, adhesive failure was observed for all groups. Dentin surface treatment with sodium bicarbonate air abrasion improves bond strength of SbU, irrespective of adhesive application mode, which makes this approach an alternative to increase adhesive performance of Scotchbond Universal Adhesive to dentin.

  10. Dentin pretreatment and adhesive temperature as affecting factors on bond strength of a universal adhesive system

    PubMed Central

    Sutil, Bruna Gabrielle da Silva; Susin, Alexandre Henrique

    2017-01-01

    Abstract Objectives: To evaluate the effects of dentin pretreatment and temperature on the bond strength of a universal adhesive system to dentin. Material and Methods: Ninety-six extracted non-carious human third molars were randomly divided into 12 groups (n=8) according to Scotchbond Universal Adhesive (SbU) applied in self-etch (SE) and etch-and-rinse (ER) mode, adhesive temperature (20°C or 37°C) and sodium bicarbonate or aluminum oxide air abrasion. After composite build up, bonded sticks with cross-sectional area of 1 mm2 were obtained to evaluate the microtensile bond strength (μTBS). The specimens were tested at a crosshead speed of 0.5 mm/min on a testing machine until failure. Fractured specimens were analyzed under stereomicroscope to determine the failure patterns in adhesive, cohesive (dentin or resin) and mixed fractures. The microtensile bond strength data was analyzed using two-way ANOVA and Tukey's test (α=5%). Results: Interaction between treatment and temperature was statistically significant for SbU applied in self-etch technique. Both dentin treatments showed higher bond strength for ER mode, regardless of adhesive temperature. When compared to control group, sodium bicarbonate increased bond strength of SbU in SE technique. Adhesive temperature did not significantly affect the μTBS of tested groups. Predominantly, adhesive failure was observed for all groups. Conclusions: Dentin surface treatment with sodium bicarbonate air abrasion improves bond strength of SbU, irrespective of adhesive application mode, which makes this approach an alternative to increase adhesive performance of Scotchbond Universal Adhesive to dentin. PMID:29069151

  11. Shear bond strengths of self-etching adhesives to caries-affected dentin on the gingival wall.

    PubMed

    Koyuturk, Alp Erdin; Sengun, Abdulkadir; Ozer, Fusun; Sener, Yagmur; Gokalp, Alparslan

    2006-03-01

    The purpose of this study was to evaluate the bonding ability of five current self-etching adhesives to caries-affected dentin on the gingival wall. Seventy extracted human molars with approximal dentin caries were employed in this study. In order to obtain caries-affected dentin on the gingival wall, grinding was performed under running water. Following which, specimens mounted in acrylic blocks and composite resins of the bonding systems were bonded to dentin with plastic rings and then debonded by shear bond strength. With Clearfil SE Bond, bonding to caries-affected dentin showed the highest bond strength. With Optibond Solo Plus Self-Etch, bonding to caries-affected dentin showed higher shear bond strength than AQ Bond, Tyrian SPE & One-Step Plus, and Prompt-L-Pop (p<0.05). Further, the bond strengths of Clearfil SE Bond and Optibond Solo Plus Self-Etch to sound dentin were higher than those of Prompt-L-Pop, AQ Bond, and Tyrian SPE & One-Step Plus (p<0.05). In conclusion, besides micromechanical interlocking through hybrid layer formation, bond strength of self-etch adhesives to dentin may be increased from additional chemical interaction between the functional monomer and residual hydroxyapatite. The results of this study confirmed that differences in bond strength among self-etching adhesives to both caries-affected and sound dentin were due to chemical composition rather than acidity.

  12. Direct reciprocity in animals: The roles of bonding and affective processes.

    PubMed

    Freidin, Esteban; Carballo, Fabricio; Bentosela, Mariana

    2017-04-01

    The presence of direct reciprocity in animals is a debated topic, because, despite its evolutionary plausibility, it is believed to be uncommon. Some authors claim that stable reciprocal exchanges require sophisticated cognition which has acted as a constraint on its evolution across species. In contrast, a more recent trend of research has focused on the possibility that direct reciprocity occurs within long-term bonds and relies on simple as well as more complex affective mechanisms such as emotional book-keeping, rudimentary and higher forms of empathy, and inequity aversion, among others. First, we present evidence supporting the occurrence of long-term reciprocity in the context of existing bonds in social birds and mammals. Second, we discuss the evidence for affective responses which, modulated by bonding, may underlie altruistic behaviours in different species. We conclude that the mechanisms that may underlie reciprocal exchanges are diverse, and that some act in interaction with bonding processes. From simple associative learning in social contexts, through emotional contagion and behavioural mimicry, to empathy and a sense of fairness, widespread and diverse social affective mechanisms may explain why direct reciprocity may not be a rare phenomenon among social vertebrates. © 2015 International Union of Psychological Science.

  13. Childhood parental bonding affects adulthood trait anxiety through self-esteem.

    PubMed

    Shimura, Akiyoshi; Takaesu, Yoshikazu; Nakai, Yukiei; Murakoshi, Akiko; Ono, Yasuyuki; Matsumoto, Yasunori; Kusumi, Ichiro; Inoue, Takeshi

    2017-04-01

    The association between trait anxiety and parental bonding has been suggested. However, the mechanism remains uncertain and there is no study focused on general adult population. We investigated the association and the mechanism between childhood parental bonding and adulthood trait anxiety in the general adult population. A cross-sectional retrospective survey was conducted in 2014 with 853 adult volunteers from the general population. The Parental Bonding Instrument, Rosenberg Self-Esteem Scale, and State-Trait Anxiety Inventory Form Y (STAI-Y) were self-administered. Structural equation modelling was used for the analysis. Childhood parental bonding affected adulthood trait anxiety indirectly mediated by self-esteem. Trait anxiety was decreased by parental care and increased by parental overprotection through self-esteem. This model explained 51.1% of the variability in STAI-Y trait anxiety scores. This study suggests an important role of self-esteem as a mediator between childhood parental bonding and adulthood trait anxiety. Copyright © 2016. Published by Elsevier Inc.

  14. Bonding Pictures: Affective Ratings Are Specifically Associated to Loneliness But Not to Empathy

    PubMed Central

    Silva, Heraldo D.; Campagnoli, Rafaela R.; Mota, Bruna Eugênia F.; Araújo, Cássia Regina V.; Álvares, Roberta Sônia R.; Mocaiber, Izabela; Rocha-Rego, Vanessa; Volchan, Eliane; Souza, Gabriela G. L.

    2017-01-01

    Responding to pro-social cues plays an important adaptive role in humans. Our aims were (i) to create a catalog of bonding and matched-control pictures to compare the emotional reports of valence and arousal with the International Affective Picture System (IAPS) pictures; (ii) to verify sex influence on the valence and arousal of bonding and matched-control pictures; (iii) to investigate if empathy and loneliness traits exert a specific influence on emotional reports for the bonding pictures. To provide a finer tool for social interaction studies, the present work defined two new sets of pictures consisting of “interacting dyads” (Bonding: N = 70) and matched controls “non-interacting dyads” (Controls: N = 70). The dyads could be either a child and an adult, or two children. Participants (N = 283, 182 women) were divided in 10 groups for the experimental sessions. The task was to rate the hedonic valence and emotional arousal of bonding and controls; and of pleasant, neutral, and unpleasant pictures from the IAPS. Effects of social-related traits, empathy and loneliness, on affective ratings were tested. Participants rated bonding pictures as more pleasant and arousing than control ones. Ratings did not differentiate bonding from IAPS pleasant pictures. Control pictures showed lower ratings than pleasant but higher ratings than neutral IAPS pictures. Women rated bonding and control pictures as more positive than men. There was no sex difference for arousal ratings. High empathic participants rated bonding and control pictures higher than low empathic participants. Also, they rated pleasant IAPS pictures more positive and arousing; and unpleasant pictures more negative and arousing than the less empathic ones. Loneliness trait, on the other hand, affected very specifically the ratings of bonding pictures; lonelier participants rated them less pleasant and less arousing than less lonely. Loneliness trait did not modulate ratings of other categories. In

  15. Bonding Pictures: Affective Ratings Are Specifically Associated to Loneliness But Not to Empathy.

    PubMed

    Silva, Heraldo D; Campagnoli, Rafaela R; Mota, Bruna Eugênia F; Araújo, Cássia Regina V; Álvares, Roberta Sônia R; Mocaiber, Izabela; Rocha-Rego, Vanessa; Volchan, Eliane; Souza, Gabriela G L

    2017-01-01

    Responding to pro-social cues plays an important adaptive role in humans. Our aims were (i) to create a catalog of bonding and matched-control pictures to compare the emotional reports of valence and arousal with the International Affective Picture System (IAPS) pictures; (ii) to verify sex influence on the valence and arousal of bonding and matched-control pictures; (iii) to investigate if empathy and loneliness traits exert a specific influence on emotional reports for the bonding pictures. To provide a finer tool for social interaction studies, the present work defined two new sets of pictures consisting of "interacting dyads" (Bonding: N = 70) and matched controls "non-interacting dyads" (Controls: N = 70). The dyads could be either a child and an adult, or two children. Participants ( N = 283, 182 women) were divided in 10 groups for the experimental sessions. The task was to rate the hedonic valence and emotional arousal of bonding and controls; and of pleasant, neutral, and unpleasant pictures from the IAPS. Effects of social-related traits, empathy and loneliness, on affective ratings were tested. Participants rated bonding pictures as more pleasant and arousing than control ones. Ratings did not differentiate bonding from IAPS pleasant pictures. Control pictures showed lower ratings than pleasant but higher ratings than neutral IAPS pictures. Women rated bonding and control pictures as more positive than men. There was no sex difference for arousal ratings. High empathic participants rated bonding and control pictures higher than low empathic participants. Also, they rated pleasant IAPS pictures more positive and arousing; and unpleasant pictures more negative and arousing than the less empathic ones. Loneliness trait, on the other hand, affected very specifically the ratings of bonding pictures; lonelier participants rated them less pleasant and less arousing than less lonely. Loneliness trait did not modulate ratings of other categories. In conclusion

  16. Maternal postnatal psychiatric symptoms and infant temperament affect early mother-infant bonding.

    PubMed

    Nolvi, Saara; Karlsson, Linnea; Bridgett, David J; Pajulo, Marjukka; Tolvanen, Mimmi; Karlsson, Hasse

    2016-05-01

    Postnatal mother-infant bonding refers to the early emotional bond between mothers and infants. Although some factors, such as maternal mental health, especially postnatal depression, have been considered in relation to mother-infant bonding, few studies have investigated the role of infant temperament traits in early bonding. In this study, the effects of maternal postnatal depressive and anxiety symptoms and infant temperament traits on mother-infant bonding were examined using both mother and father reports of infant temperament. Data for this study came from the first phase of the FinnBrain Birth Cohort Study (n=102, father reports n=62). After controlling for maternal symptoms of depression and anxiety, mother-reported infant positive emotionality, measured by infant smiling was related to better mother-infant bonding. In contrast, infant negative emotionality, measured by infant distress to limitations was related to lower quality of bonding. In regards to father-report infant temperament, only infant distress to limitations (i.e., frustration/anger) was associated with lower quality of mother-infant bonding. These findings underline the importance of infant temperament as one factor contributing to early parent-infant relationships, and counseling parents in understanding and caring for infants with different temperament traits. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Does endodontic post space irrigation affect smear layer removal and bonding effectiveness?

    PubMed

    Gu, Xin-Hua; Mao, Cai-Yun; Liang, Cong; Wang, Hui-Ming; Kern, Matthias

    2009-10-01

    The effect of different post space irrigants on smear layer removal and dentin bond strength was evaluated. Sixty-six extracted sound maxillary central incisors were endodontically treated. After post space preparation, the teeth were assigned to three groups of 22 teeth each. The teeth of these three groups were irrigated for 1 min with 17% ethylenediaminetetracetic acid (EDTA) (group 1), 5.25% sodium hypochlorite (NaOCl) (group 2), or 0.9% sodium chloride (NaCl) (group 3). In each group, eight specimens were split longitudinally for smear layer evaluation, and the other fourteen specimens were filled with a self-etching adhesive system (Panavia F). Four of 14 specimens of each group were prepared for evaluation of the resin-dentin interdiffusion zone (RDIZ) and resin tags, and the other 10 specimens were serially sectioned for push-out test analysis. Smear layer removal and bond strength were affected by different post space irrigants. EDTA removed the smear layer extremely effectively and, as a result, improved the bond strength at each region (apical, middle, and coronal) of the roots. Resin tag formation and the RDIZ were also affected by different irrigants and in accordance with bond strength. Therefore, removal of the smear layer use a self-etching luting system plays an important role in bonding effectiveness.

  18. Effect of ethanol-wet bonding with hydrophobic adhesive on caries-affected dentine.

    PubMed

    Huang, Xueqing; Li, Li; Huang, Cui; Du, Xijin

    2011-08-01

    Frequently encountered in clinical practice, caries-affected dentine (CAD) is the most challenging bonding substrate. This study evaluated the effect of ethanol-wet bonding with hydrophobic adhesive to sound dentine and to CAD. In the control groups, prepared sound dentine and CAD were bonded with Adper Single Bond 2 using a traditional water-wet bonding technique. In the experimental groups, the specimens were treated as follows: Group 1, rinsed with stepwise ethanol dehydration; Group 2, immersion in 100% ethanol, three times, for 20 s each time; and Group 3, immersion in 100% ethanol for 20 s. Microtensile bond strength (μTBS) testing was used to evaluate the effects of the different protocols on bonding. The microhardness of debonded dentine surfaces was measured to ensure the presence of CAD. Interfacial nanoleakage was evaluated by field-emission scanning electron microscopy. Treatment significantly improved the μTBS in CAD in Groups 1 and 2, but had no effect on Group 3. Conversely, treatment significantly reduced the μTBS in sound dentine in Groups 2 and 3, but had no effect in Group 1. The presence of nanoleakage varied with the ethanol-wet protocol used. In conclusion, ethanol-wet bonding can potentially improve bond efficacy to CAD when an appropriate protocol is used. © 2011 Eur J Oral Sci.

  19. Parental bonding and depression: personality as a mediating factor.

    PubMed

    Avagianou, Penelope-Alexia; Zafiropoulou, Maria

    2008-01-01

    According to Bowlby's theory of attachment, the role of early experience and parenting is of crucial importance to child development and mental health. In addition, several research findings suggest that parental bonding and different types of attachment play a crucial role in personality development. The present study examines the association between parental bonding experiences (lack of parental care, overprotection or both) and depression during adulthood. The objective of the present study was to evaluate different personality dimensions as possible mediators of the relation between perceptions of parental bonding and depressive symptoms in adult life. 181 participants (15- 49-years-old) completed the Parental Bonding Instrument (PBI), the Beck Depression Inventory (BDI) and the 16 Personality Factor Questionnaire (16PF). The results show that lack of parental care and overprotection is linked with depressive symptoms and a number of personality characteristics, such as low self-esteem, introversion, distress and emotional instability. In contrast, high care and low protection (optimal bonding) is linked with increased self-confidence, less distress and less depressive symptoms. The results presented here are in line with Bowlby's theory of attachment and show that parental bonding is linked with problematic personality development and psychopathology. The present study provided evidence that personality factors may mediate the observed relationship between parental rearing style and depression. The potential causal mechanisms warrant longitudinal evaluation.

  20. Factors affecting the cement-post interface.

    PubMed

    Zicari, F; De Munck, J; Scotti, R; Naert, I; Van Meerbeek, B

    2012-03-01

    To evaluate the effect of different factors on the push-out bond strength of glass fiber posts luted in simulated (standard) root canals using different composite cements. Three types of glass-fiber root-canal posts with a different matrix, namely an epoxy resin (RelyX post, 3M ESPE), a proprietary composite resin (FRC-Plus post, Ivoclar-Vivadent), and a methacrylate resin (GC post, GC), and three types of composite cements, namely an etch-and-rinse Bis-GMA-based (Variolink II, Ivoclar-Vivadent), a self-etch 10-MDP-based (Clearfil Esthetic Cement, Kuraray) and a self-adhesive (RelyX Unicem, 3M ESPE) cement, were tested. Posts were either left untreated (control), were treated with silane, or coated with silicated alumina particles (Cojet system, 3M ESPE). Posts were inserted up to 9-mm depth into composite CAD-CAM blocks (Paradigm, 3M ESPE) in order to solely test the strength of the cement-post interface, while excluding interference of the cement-dentin interface. After 1-week storage at 37 °C, three sections (coronal, middle, apical) of 2-mm thickness were subjected to a push-out bond-strength test. All three variables, namely the type of post, the composite cement and the post-surface pre-treatment, were found to significantly affect the push-out bond strength (p<0.001). Regarding the type of post, a significantly lower push-out bond strength was recorded for the FRC-Plus post (Ivoclar-Vivadent); regarding the composite cement, a significantly higher push-out bond strength was recorded for the self-adhesive cement Unicem (3M ESPE); and regarding the post-surface treatment, a significantly higher push-out bond strength was recorded when the post-surface was beforehand subjected to a Cojet (3M ESPE) combined sandblasting/silicatization surface pre-treatment. Many interactions between these three variables were found to be significant as well (p<0.001). Finally, the push-out bond strength was found to significantly reduce with depth from coronal to apical

  1. Depression in young adolescents: investigations using 2 and 3 factor versions of the Parental Bonding Instrument.

    PubMed

    Martin, Graham; Bergen, Helen A; Roeger, Leigh; Allison, Stephen

    2004-10-01

    Associations between parenting style and depressive symptomatology in a community sample of young adolescents (N = 2596) were investigated using self-report measures including the Parental Bonding Instrument and the Center for Epidemiologic Studies Depression Scale. Specifically, the 25-item 2-factor and 3-factor models by Parker et al. (1979), Kendler's (1996) 16-item 3-factor model, and Parker's (1983) quadrant model for the Parental Bonding Instrument were compared. Data analysis included analysis of variance and logistic regression. Reanalysis of Parker's original scale indicates that overprotection is composed of separate factors: intrusiveness (at the individual level) and restrictiveness (in the social context). All models reveal significant independent contributions from paternal care, maternal care, and maternal overprotection (2-factor) or intrusiveness (3-factor) to moderate and serious depressive symptomatology, controlling for sex and family living arrangement. Additive rather than multiplicative interactions between care and overprotection were found. Regardless of the level of parental care and affection, clinicians should note that maternal intrusiveness is strongly associated with adverse psychosocial health in young adolescents.

  2. Effect of 2% Chlorhexidine Digluconate on the Bond Strength to Normal versus Caries-Affected Dentin

    PubMed Central

    Komori, Paula C. P.; Pashley, David H.; Tjäderhane, Leo; Breschi, Lorenzo; Mazzoni, Annalisa; de Goes, Mario Fernando; Wang, Linda; Carrilho, Marcela R.

    2013-01-01

    SUMMARY This study evaluated the effect of 2% chlorhexidine digluconate (CHX) used as a therapeutic primer on the long-term bond strengths of two etch-and-rinse adhesives to normal (ND) and caries-affected (CAD) dentin. Forty extracted human molars with coronal carious lesions, surrounded by normal dentin, were selected for this study. Flat surfaces of two types of dentin (i.e. ND and CAD) were prepared with a water-cooled high speed diamond disc, and then acid-etched, rinsed and air-dried. In control groups, dentin was re-hydrated with distilled water, blot-dried and bonded with a three-step (Scotchbond Multi-Purpose-MP) or a two-step (Single Bond 2-SB) etch-and-rinse adhesive. In experimental groups, dentin was re-hydrated with 2% CHX (60 s), blot-dried and bonded with the same adhesives. Resin composite build-ups were made. Specimens were prepared for microtensile bond testing in accordance with the non-trimming technique and then tested either immediately or after 6-month storage in artificial saliva. Data were analyzed by ANOVA/Bonferroni tests (α = 0.05). CHX did not affect the immediate bond strength to ND or CAD (p>0.05). CHX treatment significantly lowered the loss of bond strength after 6 months seen in control bonds for ND (p<0.05), but it did not alter the bond strength of CAD (p>0.05). Application of MP on CHX-treated ND or CAD produced bonds that did not change over 6 months of storage. PMID:19363971

  3. Effect of 2% chlorhexidine digluconate on the bond strength to normal versus caries-affected dentin.

    PubMed

    Komori, Paula C P; Pashley, David H; Tjäderhane, Leo; Breschi, Lorenzo; Mazzoni, Annalisa; de Goes, Mario Fernando; Wang, Linda; Carrilho, Marcela R

    2009-01-01

    This study evaluated the effect of 2% chlorhexidine digluconate (CHX) used as a therapeutic primer on the long-term bond strengths of two etch-and-rinse adhesives to normal (ND) and caries-affected (CAD) dentin. Forty extracted human molars with coronal carious lesions, surrounded by normal dentin, were selected for this study. The flat surfaces of two types of dentin (ND and CAD) were prepared with a water-cooled high-speed diamond disc, then acid-etched, rinsed and air-dried. In the control groups, the dentin was re-hydrated with distilled water, blot-dried and bonded with a three-step (Scotchbond Multi-Purpose-MP) or two-step (Single Bond 2-SB) etch-and-rinse adhesive. In the experimental groups, the dentin was rehydrated with 2% CHX (60 seconds), blot-dried and bonded with the same adhesives. Resin composite build-ups were made. The specimens were prepared for microtensile bond testing in accordance with the non-trimming technique, then tested either immediately or after six-months storage in artificial saliva. The data were analyzed by ANOVA/Bonferroni tests (alpha = 0.05). CHX did not affect the immediate bond strength to ND or CAD (p > 0.05). CHX treatment significantly lowered the loss of bond strength after six months as seen in the control bonds for ND (p < 0.05), but it did not alter the bond strength of CAD (p > 0.05). The application of MP on CHX-treated ND or CAD produced bonds that did not change over six months of storage.

  4. Effect of reducing acid etching time on bond strength to noncarious and caries-affected primary and permanent dentin.

    PubMed

    Scheffel, Débora Lopes Salles; Ricci, Hérica Adad; de Souza Costa, Carlos Alberto; Pashley, David Henry; Hebling, Josimeri

    2013-01-01

    The purpose was to evaluate the effect of acid etching time on the bond strength of a simplified etch-and-rinse adhesive system to noncarious and caries-affected dentin of primary and permanent teeth. Twenty-four extracted primary and permanent teeth were divided into three groups, according to the acid etching time. Four teeth from each group were exposed to a microbiological caries-inducing protocol. After caries removal, noncarious and caries-affected dentin surfaces were etched with 37 percent phosphoric acid for five, 10, or 15 seconds prior to the application of Prime & Bond NT adhesive. Crowns were restored with resin composite and prepared for microtensile testing. Data were submitted to Kruskal-Wallis and Mann-Whitney tests (α=0.05). Higher bond strengths were obtained for noncarious dentin vs. caries-affected dentin for both primary and permanent teeth. Reducing the acid etching time from 15 to five seconds did not affect the bond strength to caries-affected or noncarious dentin in primary teeth. For permanent teeth, lower bond strength values were observed when the noncarious dentin was etched for five seconds, while no difference was seen between 10 and 15 seconds. For Prime & Bond NT, the etching of dentin for five seconds could be recommended for primary teeth, while 10 seconds would be the minimum time for permanent teeth.

  5. Children’s Bonding with Parents and Grandparents and Its Associated Factors

    PubMed Central

    Li, Yuli; Cui, Naixue; Cao, Fenglin; Liu, Jianghong

    2015-01-01

    Previous literature has focused on the importance of both parental and grandparental bonding. However, few studies have been conducted to measure children’s bonding with parents and grandparents simultaneously, especially tested by the same instrument that offers more comparable results. Therefore, we studied the relationships between parental and grandparental bonding using the Parental Bonding Instrument (PBI), and possible associations between these bonds and sociodemographic variables in 905 Chinese children aged 10–14 years. Children’s bonding with mother, father, and grandparents were positively correlated, and the final mixed-effect model showed that several sociodemographic factors (e.g., gender, only children, parents’ marital status, and mother’s occupation) were associated with parental and grandparental bonding. PMID:27284385

  6. Degradation of Multimode Adhesive System Bond Strength to Artificial Caries-Affected Dentin Due to Water Storage.

    PubMed

    Follak, A C; Miotti, L L; Lenzi, T L; Rocha, R O; Soares, F Z

    The purpose of this study was to evaluate the influence of water storage on bond strength of multimode adhesive systems to artificially induced caries-affected dentin. One hundred twelve sound bovine incisors were randomly assigned to 16 groups (n=7) according to the dentin condition (sound; SND, artificially induced caries-affected dentin; CAD, cariogenic challenge by pH cycling for 14 days); the adhesive system (SU, Scotchbond Universal Adhesive; AB, All-Bond Universal; PB, Prime & Bond Elect; SB, Adper Single Bond 2; and CS, Clearfil SE Bond), and the etching strategy (etch-and-rinse and self-etch). All adhesive systems were applied under manufacturer's instructions to flat dentin surfaces, and a composite block was built up on each dentin surface. After 24 hours of water storage, the specimens were sectioned into stick-shaped specimens (0.8 mm 2 ) and submitted to a microtensile test immediately (24 hours) or after six months of water storage. Bond strength data (MPa) were analyzed using three-way repeated-measures analysis of variance and post hoc Tukey test (α=5%), considering each substrate separately (SND and CAD). The etching strategy did not influence the bond strength of multimode adhesives, irrespective of the dentin condition. Water storage only reduced significantly the bond strength to CAD. The degradation of bond strength due to water storage was more pronounced in CAD, regardless of the etching strategy.

  7. Evaluation of microtensile bond strength of self-etching adhesives on normal and caries-affected dentin.

    PubMed

    Shibata, Shizuma; Vieira, Luiz Clovis Cardoso; Baratieri, Luiz Narciso; Fu, Jiale; Hoshika, Shuhei; Matsuda, Yasuhiro; Sano, Hidehiko

    2016-01-01

    The purpose of this study was to evaluate the µTBS (microtensile bond strength) of currently available self-etching adhesives with an experimental self-etch adhesive in normal and caries-affected dentin, using a portable hardness measuring device, in order to standardize dentin Knoop hardness. Normal (ND) and caries-affected dentin (CAD) were obtained from twenty human molars with class II natural caries. The following adhesive systems were tested: Mega Bond (MB), a 2-step self-etching adhesive; MTB-200 (MTB), an experimental 1-step self-etching adhesive (1-SEA), and two commercially available one-step self-etching systems, G-Bond Plus (GB) and Adper Easy Bond (EB). MB-ND achieved the highest µTBS (p<0.05). The mean µTBS was statistically lower in CAD than in ND for all adhesives tested (p<0.05), and the 2-step self-etch adhesive achieved better overall performance than the 1-step self-etch adhesives.

  8. Bonding durability of a self-etching primer system to normal and caries-affected dentin under hydrostatic pulpal pressure in vitro.

    PubMed

    Nakajima, Masatoshi; Hosaka, Keiichi; Yamauti, Monica; Foxton, Richard M; Tagami, Junji

    2006-06-01

    To evaluate the bonding durability of a self-etching primer system to normal and caries-affected dentin under hydrostatic pulpal pressure. 18 extracted human molars with occlusal caries were used. Their occlusal dentin surfaces were ground flat to expose normal and caries-affected dentin using #600 SiC paper under running water. Clearfil SE Bond was placed on the dentin surface including the caries-affected dentin according to the manufacturer's instructions and then the crowns were built up with resin composite (Clearfil AP-X) under either a pulpal pressure of 15 cm H2O or none (control). The bonded specimens were stored in 100% humidity for 1 day (control) or for 1 week and 1 month with hydrostatic pulpal pressure. After storage, the specimens were serially sectioned into 0.7 mm-thick slabs and trimmed to an hour-glass shape with a 1 mm2 cross-section, isolated by normal or caries-affected dentin, and then subjected to the micro-tensile bond test. Data were analyzed by two-way ANOVA and Tukey's test (P< 0.05). Hydrostatic pulpal pressure significantly reduced the bond strength to normal dentin after 1-month storage (P< 0.05), but did not affect the bond strength to caries-affected dentin.

  9. Cigarette smoke affects bonding to dentin.

    PubMed

    Almeida e Silva, Junio S; de Araujo, Edson Medeiro; Araujo, Elito

    2010-01-01

    This in vitro study evaluated the microtensile bond strength (muTBS) of composite resin bonded to dentin that had been contaminated by cigarette smoke. Ten extracted unerupted human third molars were used: Six molars were prepared for muTBS testing, while the other four molars were assigned to pre- and post-etching scanning electronic microscopy (SEM) analysis. The 20 specimens obtained from the 10 coronal portions were distributed into two experimental groups so that each tooth served as its own control. Group 1 underwent a daily toothbrushing simulation and exposure to a smoking simulation chamber, while Group 2 received only a daily simulated toothbrushing. Student's t-test demonstrated that Group 1 samples demonstrated significantly lower bond strength (49.58 MPa) than Group 2 samples (58.48 MPa). Pre and postetching SEM analysis revealed the presence of contaminants on the dentinal surfaces of the Group 1 specimens. It was concluded that contamination by cigarette smoke decreases the bond strength between dentin and composite resin.

  10. [EARLY MOTHER-CHILD BONDING FACTORS ASSOCIATED WITH CHILDREN OBESITY].

    PubMed

    Vargas Martínez, Gabriela; Cruzat Mandich, Claudia; Díaz Castrillón, Fernanda; Moore Infante, Catalina; Ulloa Jiménez, Valentina

    2015-11-01

    The aim of this study is to describe the experience of a group of mothers with obese children, regarding how early bond affects the relationship that both have with food and this, in turn, impacts on childhood obesity. The present study has a qualitative, exploratory and descriptive design. The sample consists of five chilean women between 22 and 39 years old, with obese children between 2 and 4 years old. In-depth interviews were carried out and open coding strategy was used as method of analysis. Results show a tendency of mothers to establish insecure attachment relations, difficulties of tuning and expression of affection, and a predominance of a permissive parenting style around food. This has important implications for prevention and treatment of obesity, focusing on the attachment bond between mother and child. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  11. The impact of artificially caries-affected dentin on bond strength of multi-mode adhesives

    PubMed Central

    Follak, Andressa Cargnelutti; Miotti, Leonardo Lamberti; Lenzi, Tathiane Larissa; Rocha, Rachel de Oliveira; Maxnuck Soares, Fabio Zovico

    2018-01-01

    Aim: The aim of this study is to evaluate the impact of dentin condition on bond strength of multi-mode adhesive systems (MMAS) to sound and artificially induced caries-affected dentin (CAD). Methods: Flat dentin surfaces of 112 bovine incisors were assigned to 16 subgroups (n = 7) according to the substrate condition (sound and CAD– pH-cycling for 14 days); adhesive systems (Scotchbond Universal, All-Bond Universal, Prime and Bond Elect, Adper Single Bond Plus and Clearfil SE Bond) and etching strategy (etch-and-rinse and self-etch). All systems were applied according to the manufacturer's instructions, and resin composite restorations were built. After 24 h of water storage, specimens were sectioned (0.8 mm2) and submitted to the microtensile test. Statistical Analysis: Data (MPa) were analyzed using three-way analysis of variance and Tukey's test (α = 0.05). Results: MMAS presented similar bond strength values, regardless etching strategy in each substrate condition. Bond strength values were lower when MMAS were applied to CAD in the etch-and-rinse strategy. Conclusion: The etching strategy did not influence the bond strength of MMAS to sound or CAD, considering each substrate separately. However, CAD impact negatively on bond strength of MMAS in etch-and rinse mode. PMID:29674813

  12. Does Acid Challenge Affect the Properties and Bond Stability of Restorative Materials on Primary Teeth?

    PubMed

    Tedesco, Tamara K; Calvo, Ana F B; Yoshioka, Laysa; Fukushima, Karen A; Cesar, Paulo F; Raggio, Daniela P

    2018-05-31

    To evaluate the effect of acidic challenge (AC) on the properties and bond stability of restorative materials to primary enamel and dentin. One hundred twenty primary molars were assigned to 12 groups according to substrate (enamel or dentin), restorative material (composite, high-viscosity glass ionomer cement [HV-GIC] or resin-modified glass-ionomer cement [RM-GIC]), and immersion after restoration (control [saline solution/7 days] or AC [cola-based drink/5 min/3x per day/7 days]). Twenty-four hours after the restorative procedure, specimens were submitted to one of the proposed challenges. Half of the specimens were immediately subjected to the microshear bond strength test, and the other half after 12 months. To determine flexural strength flexural strength and superficial roughness (SR), 30 specimens were built up. After 24 h, the first measurement of SR from 10 specimens was performed. Specimens were then immersed in one of proposed challenges and SR was measured again. Subsequently, flexural strength testing was performed. Bond strength, surface roughness, and flexural strength data were subjected to ANOVA and Tukey's test. Composite showed the highest bond strengths compared to the others materials on both substrates. The storage period negatively influenced the bond strength only for composite groups in dentin. AC after restoration negatively influenced bond strength when the materials were evaluated in eroded dentin. AC affected the second SR measurement, showing increased SR for all restorative materials. AC did not affect flexural strength. The acidic challenge jeopardizes the surface roughness and bond strength of restorations to eroded dentin.

  13. A Study of the Predictability of School District Bond Ratings.

    ERIC Educational Resources Information Center

    Vedra, Kenneth David

    School district bond ratings, issued on request by Standard and Poor's Corporation or Moody's Investors Service, hold implications for school districts' financial management. Ultimately, the bond rating assigned is a factor affecting the total cost of the bond issuance, related to the principal and interest payments over the life of the debt. A…

  14. An energetic scale for equilibrium H/D fractionation factors illuminates hydrogen bond free energies in proteins

    PubMed Central

    Cao, Zheng; Bowie, James U

    2014-01-01

    Equilibrium H/D fractionation factors have been extensively employed to qualitatively assess hydrogen bond strengths in protein structure, enzyme active sites, and DNA. It remains unclear how fractionation factors correlate with hydrogen bond free energies, however. Here we develop an empirical relationship between fractionation factors and free energy, allowing for the simple and quantitative measurement of hydrogen bond free energies. Applying our empirical relationship to prior fractionation factor studies in proteins, we find: [1] Within the folded state, backbone hydrogen bonds are only marginally stronger on average in α-helices compared to β-sheets by ∼0.2 kcal/mol. [2] Charge-stabilized hydrogen bonds are stronger than neutral hydrogen bonds by ∼2 kcal/mol on average, and can be as strong as –7 kcal/mol. [3] Changes in a few hydrogen bonds during an enzyme catalytic cycle can stabilize an intermediate state by –4.2 kcal/mol. [4] Backbone hydrogen bonds can make a large overall contribution to the energetics of conformational changes, possibly playing an important role in directing conformational changes. [5] Backbone hydrogen bonding becomes more uniform overall upon ligand binding, which may facilitate participation of the entire protein structure in events at the active site. Our energetic scale provides a simple method for further exploration of hydrogen bond free energies. PMID:24501090

  15. Grandparents Affected by Parental Divorce: A Population at Risk?

    ERIC Educational Resources Information Center

    Myers, Jane E.; Perrin, Novella

    1993-01-01

    When parents divorce, grandparents who have bonded with children may be affected, especially when denied visitation. Grandparenting roles and styles, family dynamics affecting grandparenthood, and other factors affecting the grandparent-grandchild bond are examined. Legal and ethical issues are discussed. Implications for counselors and human…

  16. Assessment of post-contamination treatments affecting different bonding stages to dentin

    PubMed Central

    Elkassas, Dina; Arafa, Abla

    2016-01-01

    Objectives: To assess the effect of cleansing treatments following saliva and blood contamination at different bonding stages to dentin. Materials and Methods: Labial surfaces of 168 permanent maxillary central incisors were ground flat exposing superficial dentin. Specimens were divided into: uncontaminated control (A), contamination after etching (B), contamination after adhesive application (C), contamination after adhesive polymerization (D). Groups were further subdivided according to cleansing treatments into: rinsing (B1, C1, D1), re-etching (B2, D3), sodium hypochlorite application (B3), ethyl alcohol application (C2), acetone application (C3), rinsing and rebonding (D2), re-etching and rebonding (D4). Composite microcylinders were bonded to treated substrates and shear loaded micro-shear bond strength (μSBS) until failure and treated surfaces were examined with scanning electron microscope. Debonded surfaces were classified as adhesive, cohesive or mixed failure. The data were analyzed using one-way ANOVA and Tukey's post hoc test. Results: The μSBS values were ranked as follow; Group B: A > B3 > B2 > B1 > B, Group C: A > C3 > C2 > C1 > C, Group D: A > D4 > D1 = D2 ≥ D3. Debonded surfaces showed adhesive failure in Group B while cohesive failure in Groups C and D. Conclusions: Cleansing treatments differ according to bonding step; re-etching then rebonding suggested if etched substrate or polymerized adhesive were contaminated while acetone application decontaminated affected unpolymerized adhesive. PMID:27403048

  17. Does Shortened Application Time Affect Long-Term Bond Strength of Universal Adhesives to Dentin?

    PubMed

    Saikaew, P; Matsumoto, M; Chowdhury, Afma; Carvalho, R M; Sano, H

    2018-04-09

    This study evaluated the effect of shortened application time on long-term bond strength with universal adhesives. Three universal adhesives were used: Clearfil Universal Bond (CU, Kuraray Noritake Dental Inc, Tokyo, Japan), Scotchbond Universal Adhesive (SB, 3M ESPE, St Paul, MN, USA) or G-Premio Bond (GP, GC Corp, Tokyo, Japan). Sixty molars were cut to expose midcoronal dentin and prepared with a regular diamond bur. Each adhesive was applied either according to the manufacturer's instruction or with shortened time. Specimens were stored in distilled water at 37°C for 24 hours and then cut into resin-dentin sticks. Microtensile bond strength (μTBS) was tested after either 24 hours or 1 year of water storage. Data were analyzed by the three-way ANOVA and Duncan tests ( α=0.05). Fracture modes were analyzed under a scanning electron microscope (SEM). One dentin stick per group was selected after fracture mode analysis and further observed using transmission electron microscopy (TEM). Six additional dentin discs were prepared and conditioned with each adhesive under the different application time to observe the adhesive-smear layer interaction by SEM. Shortened application time affected the μTBS ( p<0.001) while storage time did not affect bond strength ( p=0.187). A significant effect of shortened application time on μTBS was observed in the CU at 1 year and in the GP at both storage times. One-year storage time had no effect on the μTBS of universal adhesives to bur-cut dentin. The performance of universal adhesives can be compromised when applied using a shortened application time.

  18. Determination of apparent coupling factors for adhesive bonded acrylic plates using SEAL approach

    NASA Astrophysics Data System (ADS)

    Pankaj, Achuthan. C.; Shivaprasad, M. V.; Murigendrappa, S. M.

    2018-04-01

    Apparent coupling loss factors (CLF) and velocity responses has been computed for two lap joined adhesive bonded plates using finite element and experimental statistical energy analysis like approach. A finite element model of the plates has been created using ANSYS software. The statistical energy parameters have been computed using the velocity responses obtained from a harmonic forced excitation analysis. Experiments have been carried out for two different cases of adhesive bonded joints and the results have been compared with the apparent coupling factors and velocity responses obtained from finite element analysis. The results obtained from the studies signify the importance of modeling of adhesive bonded joints in computation of the apparent coupling factors and its further use in computation of energies and velocity responses using statistical energy analysis like approach.

  19. Let's stay together? Intrinsic and extrinsic factors involved in pair bond dissolution in a recolonizing wolf population.

    PubMed

    Milleret, Cyril; Wabakken, Petter; Liberg, Olof; Åkesson, Mikael; Flagstad, Øystein; Andreassen, Harry Peter; Sand, Håkan

    2017-01-01

    For socially monogamous species, breeder bond dissolution has important consequences for population dynamics, but the extent to which extrinsic or intrinsic population factors causes pair dissolution remain poorly understood, especially among carnivores. Using an extensive life-history data set, a survival analysis and competing risks framework, we examined the fate of 153 different wolf (Canis lupus) pairs in the recolonizing Scandinavian wolf population, during 14 winters of snow tracking and DNA monitoring. Wolf pair dissolution was generally linked to a mortality event and was strongly affected by extrinsic (i.e. anthropogenic) causes. No divorce was observed, and among the pair dissolution where causes have been identified, death of one or both wolves was always involved. Median time from pair formation to pair dissolution was three consecutive winters (i.e. approximately 2 years). Pair dissolution was mostly human-related, primarily caused by legal control actions (36·7%), verified poaching (9·2%) and traffic-related causes (2·1%). Intrinsic factors, such as disease and age, accounted for only 7·7% of pair dissolutions. The remaining 44·3% of dissolution events were from unknown causes, but we argue that a large portion could be explained by an additional source of human-caused mortality, cryptic poaching. Extrinsic population factors, such as variables describing the geographical location of the pair, had a stronger effect on risk of pair dissolution compared to anthropogenic landscape characteristics. Population intrinsic factors, such as the inbreeding coefficient of the male pair member, had a negative effect on pair bond duration. The mechanism behind this result remains unknown, but might be explained by lower survival of inbred males or more complex inbreeding effects mediated by behaviour. Our study provides quantitative estimates of breeder bond duration in a social carnivore and highlights the effect of extrinsic (i.e. anthropogenic) and

  20. Integrative Review of Factors and Interventions That Influence Early Father-Infant Bonding.

    PubMed

    Scism, Ashley Renee; Cobb, Robin Lynn

    To report on the current state of research analyzing early father-infant bonding, including influential factors and interventions, to identify gaps in the literature. CINAHL, MEDLINE, PubMed, and PsychInfo computerized databases were searched using the keywords bonding, paternal, father, infant, relationship, engrossment, and postpartum. Twenty-eight articles were compiled on the basis of key inclusion criteria. Quality measures were undertaken using specific components of SQUIRE 2.0 to ensure quality of methodology and data. Each study was carefully dissected and initially arranged in a generic annotated bibliography. This process resulted in pattern recognition and identification of three major themes. The findings of every article were compared for commonalities and differences and were synthesized into an integrated review of father-infant bonding. The synthesis revealed three themes: Father's Adjustment and Transition, Variables That Influence Father-Infant Bonding, and Interventions That Promote Father-Infant Bonding. There is an immediate need to perform studies on specific interventions aimed at the promotion of early father-infant bonding in the United States. More research is needed to better understand the timing of early father-infant bonding and how this bonding influences a provider's role, attitude, and priority for establishing successful bonding interventions for fathers. Copyright © 2017 AWHONN, the Association of Women’s Health, Obstetric and Neonatal Nurses. Published by Elsevier Inc. All rights reserved.

  1. GROUT-CONCRETE INTERFACE BOND PERFORMANCE: EFFECT OF INTERFACE MOISTURE ON THE TENSILE BOND STRENGTH AND GROUT MICROSTRUCTURE.

    PubMed

    De la Varga, I; Muñoz, J F; Bentz, D P; Spragg, R P; Stutzman, P E; Graybeal, B A

    2018-05-01

    Bond between two cementitious materials is crucial in applications such as repairs, overlays, and connections of prefabricated bridge elements (PBEs), to name just a few. It is the latter that has special interest to the authors of this paper. After performing a dimensional stability study on grout-like materials commonly used as connections between PBEs, it was observed that the so-called 'non-shrink' cementitious grouts showed a considerable amount of early-age shrinkage. This might have negative effects on the integrity of the structure, due not only to the grout material's early degradation, but also to a possible loss of bond between the grout and the prefabricated concrete element. Many factors affect the bond strength between two cementitious materials (e.g., grout-concrete), the presence of moisture at the existing concrete substrate surface being one of them. In this regard, pre-moistening the concrete substrate surface prior to the application of the grout material is sometimes recommended for bond enhancement. This topic has been the focus of numerous research studies in the past; however, there is still controversy among practitioners on the real benefits that this practice might provide. This paper evaluates the tensile bond performance of two non-shrink cementitious grouts applied to the exposed aggregate surface of a concrete substrate, and how the supply of moisture at the grout-concrete interface affects the bond strength. "Pull-off" bond results show increased tensile bond strength when the concrete surface is pre-moistened. Reasons to explain the observed increased bond strength are given after a careful microstructural analysis of the grout-concrete interface. Interfaces where sufficient moisture is provided to the concrete substrate such that moisture movement from the grout is prevented show reduced porosity and increased hydration on the grout side of the interface, which is thought to directly contribute to the increased tensile bond

  2. Does time after pair bond disruption affect subsequent reproduction in the socially monogamous woodland vole (Microtus pinetorum)?

    PubMed Central

    Renfro, Caroline A.; Pesek, Daniel W.; Bobeck, Kelly; Solomon, Nancy G.

    2010-01-01

    Disruption of the pair bond between socially monogamous animals leads to changes in behavior, which may have reproductive consequences. There are two alternative hypotheses to explain the effect of the length of time since pair bond disruption on subsequent reproduction. One hypothesis predicts that voles housed immediately with a new opposite-sex conspecific will be as likely to produce litters and will produce them as quickly as voles separated from their initial mate for longer. Alternatively, if attachment between mates is enduring, we expect that more voles separated longer from their previous mates will produce litters and produce them sooner than voles re-paired immediately after separation from their initial mates. Woodland voles, paired with opposite-sex conspecifics, remained together until parturition. Mates were then separated for zero, seven, or fourteen days until re-pairing with an opposite-sex conspecific. Pair bond disruption did not prevent males and females from mating subsequently, which was consistent with data from our breeding colony. In addition, the length of time an individual remained alone after pair bond disruption did not affect the latency to produce a litter. Our results show that having been paired previously does not affect subsequent reproduction in this socially monogamous vole. PMID:19429197

  3. Adhesive bonding and performance testing of bonded wood products

    Treesearch

    Charles R. Frihart

    2005-01-01

    Despite the importance of durable wood bonds, the factors that lead to durability are not well understood, and the internal forces exerted upon the bondline are often overlooked. Durability requires that the bonded assembly resist dimensional changes of wood with fluctuation of wood moisture levels. Both bonding and bond breaking steps need to be understood at cellular...

  4. Investigation of ball bond integrity for 0.8 mil (20 microns) diameter gold bonding wire on low k die in wire bonding technology

    NASA Astrophysics Data System (ADS)

    Kudtarkar, Santosh Anil

    Microelectronics technology has been undergoing continuous scaling to accommodate customer driven demand for smaller, faster and cheaper products. This demand has been satisfied by using novel materials, design techniques and processes. This results in challenges for the chip connection technology and also the package technology. The focus of this research endeavor was restricted to wire bond interconnect technology using gold bonding wires. Wire bond technology is often regarded as a simple first level interconnection technique. In reality, however, this is a complex process that requires a thorough understanding of the interactions between the design, material and process variables, and their impact on the reliability of the bond formed during this process. This research endeavor primarily focused on low diameter, 0.8 mil thick (20 mum) diameter gold bonding wire. Within the scope of this research, the integrity of the ball bond formed by 1.0 mil (25 mum) and 0.8 mil (20 mum) diameter wires was compared. This was followed by the evaluation of bonds formed on bond pads having doped SiO2 (low k) as underlying structures. In addition, the effect of varying the percentage of the wire dopant, palladium and bonding process parameters (bonding force, bond time, ultrasonic energy) for 0.8 mil (20 mum) bonding wire was also evaluated. Finally, a degradation empirical model was developed to understand the decrease in the wire strength. This research effort helped to develop a fundamental understanding of the various factors affecting the reliability of a ball bond from a design (low diameter bonding wire), material (low k and bonding wire dopants), and process (wire bonding process parameters) perspective for a first level interconnection technique, namely wire bonding. The significance of this research endeavor was the systematic investigation of the ball bonds formed using 0.8 mil (20 microm) gold bonding wire within the wire bonding arena. This research addressed low k

  5. Factors affecting sign retroreflectivity

    DOT National Transportation Integrated Search

    2001-01-01

    This study was undertaken to better understand the factors that may affect road sign retroreflectivity, specifically age and physical orientation. A better understanding of these factors could provide guidance to ODOT in managing its inventory of roa...

  6. Effects of single bond-ion and single bond-diradical form on the stretching vibration of Cdbnd N bridging bond in 4,4‧-disubstituted benzylidene anilines

    NASA Astrophysics Data System (ADS)

    Cao, Chao-Tun; Bi, Yakun; Cao, Chenzhong

    2016-06-01

    Fifty-seven samples of model compounds, 4,4‧-disubstituted benzylidene anilines, p-X-ArCH = NAr-p-Y were synthesized. Their infrared absorption spectra were recorded, and the stretching vibration frequencies νCdbnd N of the Cdbnd N bridging bond were determined. New stretching vibration mode was proposed by means of the analysis of the factors affecting νCdbnd N, that is there are mainly three modes in the stretching vibration of Cdbnd N bond: (I) polar double bond form Cdbnd N, (II) single bond-ion form C+-N- and (III) single bond-diradical form Crad -Nrad . The contributions of the forms (I) and (II) to the change of νCdbnd N can be quantified by using Hammett substituent constant (including substituent cross-interaction effects between X and Y groups), whereas the contribution of the form (III) can be quantified by employing the excited-state substituent constant. The most contribution of these three forms is the form (III), the next is the form (II), whose contribution difference was discussed with the viewpoint of energy requirements in vibration with the form (III) and form (II).

  7. Autoregulation of von Willebrand factor function by a disulfide bond switch

    PubMed Central

    Butera, Diego; Passam, Freda; Ju, Lining; Cook, Kristina M.; Woon, Heng; Aponte-Santamaría, Camilo; Gardiner, Elizabeth; Davis, Amanda K.; Murphy, Deirdre A.; Bronowska, Agnieszka; Luken, Brenda M.; Baldauf, Carsten; Jackson, Shaun; Andrews, Robert; Gräter, Frauke; Hogg, Philip J.

    2018-01-01

    Force-dependent binding of platelet glycoprotein Ib (GPIb) receptors to plasma von Willebrand factor (VWF) plays a key role in hemostasis and thrombosis. Previous studies have suggested that VWF activation requires force-induced exposure of the GPIb binding site in the A1 domain that is autoinhibited by the neighboring A2 domain. However, the biochemical basis of this “mechanopresentation” remains elusive. From a combination of protein chemical, biophysical, and functional studies, we find that the autoinhibition is controlled by the redox state of an unusual disulfide bond near the carboxyl terminus of the A2 domain that links adjacent cysteine residues to form an eight-membered ring. Only when the bond is cleaved does the A2 domain bind to the A1 domain and block platelet GPIb binding. Molecular dynamics simulations indicate that cleavage of the disulfide bond modifies the structure and molecular stresses of the A2 domain in a long-range allosteric manner, which provides a structural explanation for redox control of the autoinhibition. Significantly, the A2 disulfide bond is cleaved in ~75% of VWF subunits in healthy human donor plasma but in just ~25% of plasma VWF subunits from heart failure patients who have received extracorporeal membrane oxygenation support. This suggests that the majority of plasma VWF binding sites for platelet GPIb are autoinhibited in healthy donors but are mostly available in heart failure patients. These findings demonstrate that a disulfide bond switch regulates mechanopresentation of VWF. PMID:29507883

  8. Autoregulation of von Willebrand factor function by a disulfide bond switch.

    PubMed

    Butera, Diego; Passam, Freda; Ju, Lining; Cook, Kristina M; Woon, Heng; Aponte-Santamaría, Camilo; Gardiner, Elizabeth; Davis, Amanda K; Murphy, Deirdre A; Bronowska, Agnieszka; Luken, Brenda M; Baldauf, Carsten; Jackson, Shaun; Andrews, Robert; Gräter, Frauke; Hogg, Philip J

    2018-02-01

    Force-dependent binding of platelet glycoprotein Ib (GPIb) receptors to plasma von Willebrand factor (VWF) plays a key role in hemostasis and thrombosis. Previous studies have suggested that VWF activation requires force-induced exposure of the GPIb binding site in the A1 domain that is autoinhibited by the neighboring A2 domain. However, the biochemical basis of this "mechanopresentation" remains elusive. From a combination of protein chemical, biophysical, and functional studies, we find that the autoinhibition is controlled by the redox state of an unusual disulfide bond near the carboxyl terminus of the A2 domain that links adjacent cysteine residues to form an eight-membered ring. Only when the bond is cleaved does the A2 domain bind to the A1 domain and block platelet GPIb binding. Molecular dynamics simulations indicate that cleavage of the disulfide bond modifies the structure and molecular stresses of the A2 domain in a long-range allosteric manner, which provides a structural explanation for redox control of the autoinhibition. Significantly, the A2 disulfide bond is cleaved in ~75% of VWF subunits in healthy human donor plasma but in just ~25% of plasma VWF subunits from heart failure patients who have received extracorporeal membrane oxygenation support. This suggests that the majority of plasma VWF binding sites for platelet GPIb are autoinhibited in healthy donors but are mostly available in heart failure patients. These findings demonstrate that a disulfide bond switch regulates mechanopresentation of VWF.

  9. Parental bonding in males with adjustment disorder and hyperventilation syndrome.

    PubMed

    Lung, For-Wey; Lee, Ting-Hsuan; Huang, Mei-Feng

    2012-06-06

    The purpose of the study was to identify the style of parental bonding and the personality characteristics that might increase the risk of hyperventilation and adjustment disorder. A total of 917 males were recruited, 156 with adjustment disorder and hyperventilation syndrome (AD + HY), 273 with adjustment disorder without hyperventilation syndrome (AD-HY), and 488 healthy controls. All participants completed the Parental Bonding Instrument, Eysenck Personality Questionnaire, and Chinese Health Questionnaire. Analysis using structural equation models identified a pathway relationship in which parental bonding affected personality characteristics, personality characteristics affected mental health condition, and mental health condition affected the development of hyperventilation or adjustment disorder. Males with AD-HY perceived less paternal care, and those with AD + HY perceived more maternal protection than those with adjustment disorder and those in the control group. Participants with AD-HY were more neurotic and less extroverted than those with AD + HY. Both groups showed poorer mental health than the controls. Although some patients with hyperventilation syndrome demonstrated symptoms of adjustment disorder, there were different predisposing factors between the two groups in terms of parental bonding and personality characteristics. This finding is important for the early intervention and prevention of hyperventilation and adjustment disorder.

  10. Can Parental Bonding Be Assessed in Children? Factor Structure and Factorial Invariance of the Parental Bonding Instrument (PBI) between Adults and Children

    ERIC Educational Resources Information Center

    Tsaousis, Ioannis; Mascha, Katerina; Giovazolias, Theodoros

    2012-01-01

    This study examined the factorial structure of the Parental Bonding Instrument (PBI) in the Greek population. Using confirmatory factor analysis different proposed models of the basic dimensions of PBI were evaluated. The results indicated that Kendler's three-factor (i.e. care, protectiveness and authoritarianism) solution was found to be more…

  11. The marginal effect of bond insurance on hospital, tax-exempt bond yields.

    PubMed

    Carpenter, C E

    1991-01-01

    In response to changes in the health care environment and the tax-exempt bond market, many hospitals have purchased bond insurance and other forms of credit enhancement to lower the yields on their debt financings. This study of tax-exempt revenue bonds issued by hospitals from 1982-84 estimates that bond insurance lowers yields on hospital bonds by approximately 87 basis points and that bond insurance serves as a substitute measure of creditworthiness. The findings also suggest that the insured group of hospital bonds is more homogeneous than the uninsured group in terms of characteristics that affect the risks associated with hospital investments. Insured bonds seem to represent hospitals in an intermediate risk group.

  12. Association of bond, market, operational, and financial factors with multi-hospital system bond issues.

    PubMed

    Carpenter, C E; McCue, M J; Hossack, J B

    2001-01-01

    Despite the growth of multi-hospital systems in the 1990s, their performance in the tax-exempt bond market has not been adequately evaluated. The purpose of this study is to compare bonds issued by multi-hospital systems to those issued by individual hospitals in terms of bond, market, operational, and financial characteristics. The study sample includes 2,078 newly issued, tax-exempt, revenue bonds between 1991 and 1997. The findings indicate that multi-hospital systems issued larger amounts of debt at a lower cost, were more likely to be insured, had higher debt service coverage and higher operating margins.

  13. Parental bonding during childhood affects stress-coping ability and stress reaction.

    PubMed

    Ohtaki, Yuh; Ohi, Yuichi; Suzuki, Shun; Usami, Kazuya; Sasahara, Shinichiro; Matsuzaki, Ichiyo

    2017-07-01

    An online survey examined the effects of parental bonding during childhood on adult workers' stress-coping ability (Sense of Coherence) and stress reactions (General Health Questionnaire and Self-Rating Depression Scale). Participants who completed the questionnaire were grouped into optimal bonding and poor bonding groups. Analyses of covariance by gender with age as a covariate were conducted for the Sense of Coherence, General Health Questionnaire, and Self-Rating Depression Scale scores for 9525 participants. For both genders, the scores of the poor bonding group were significantly lower for the Sense of Coherence and significantly higher for the General Health Questionnaire and Self-Rating Depression Scale compared to those of the optimal bonding group.

  14. Factors affecting construction performance: exploratory factor analysis

    NASA Astrophysics Data System (ADS)

    Soewin, E.; Chinda, T.

    2018-04-01

    The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.

  15. [Curing mode of universal adhesives affects the bond strength of resin cements to dentin].

    PubMed

    Fu, Z R; Tian, F C; Zhang, L; Han, B; Wang, X Y

    2017-02-18

    To determine the effects of curing mode of one-step and two-step universal adhesives on the micro-tensile bond strength (μTBS) of different dual-cure resin cements to dentin. One-step universal adhesive Single Bond Universal (SBU), and two-step universal adhesive OptiBond Versa (VSA) were chosen as the subjects, one-step self-etching adhesive OptiBond All in One (AIO) and two-step self-etching adhesive Clearfil SE Bond (SEB) were control groups, and two dual-cure resin cements RelyX Ultimate (RLX) and Nexus 3 Universal (NX3) were used in this study. In this study, 80 extracted human molars were selected and the dentin surface was exposed using diamond saw. The teeth were divided into 16 groups according to the adhesives (AIO, SBU, SEB, VSA), cure modes of adhesives (light cure, non-light cure) and resin cements (RLX, NX3). The adhesives were applied on the dentin surface following the instruction and whether light cured or not, then the resin cements were applied on the adhesives with 1 mm thickness and light cured (650 mW/cm(2) for 20 s. A resin was built up (5 mm) on the cements and light cured layer by layer. After water storage for 24 h, the specimens were cut into resin-cement-dentin strips with a cross sectional area of 1 mm×1 mm and the μTBS was measured. Regarding one-step universal adhesive (SBU) light cured, the μTBS with RLX [(35.45±7.04) MPa] or NX3 [(26.84±10.39) MPa] were higher than SBU non-light cured with RLX [(17.93±8.93) MPa)] or NX3 [(10.07±5.89) MPa, P<0.001]. Compared with AIO, light-cured SBU combined with RLX presented higher μTBS than AIO group [(35.45±7.04) MPa vs. (24.86±8.42) MPa, P<0.05]. When SBU was not lighted, the μTBS was lower than AIO [(17.93±8.93) MPa vs. (22.28±7.57) MPa, P<0.05]. For two-step universal adhesive (VSA) and control adhesive (SEB), curing mode did not affect the μTBS when used with either RLX or NX3 (25.98-32.24 MPa, P>0.05). Curing mode of one-step universal adhesive may affect the μTBS between

  16. A Persian version of the parental bonding instrument: factor structure and psychometric properties.

    PubMed

    Behzadi, Behnaz; Parker, Gordon

    2015-02-28

    The Parental Bonding Instrument (PBI) is a widely used self-report measure for quantifying key parenting styles as perceived by the child during its first 16 years. While its development study identified two key parental dimensions, subsequent studies have variably confirmed those two or argued for one or more additional parental constructs. We developed a Persian translation of the PBI and administered it to a sample of 340 high school students. The construct validity of the Persian PBI was examined by Exploratory Factor Analysis while Confirmatory Factor Analysis was used to identify the most adequate model. Analyses of the Persian PBI favored a four-factor model for both parental forms. The Persian PBI has a factorial structure consistent with constructs identified in western cultures, as well as high internal consistency and test-retest reliability. Multivariate analyses indicated significant differences between boys and girls across some factors. The PBI appears an acceptable and appropriate measure for quantifying parent-child bonding in Iranian samples. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  17. Do bonding and bridging social capital affect self-rated health, depressive mood and cognitive decline in older Japanese? A prospective cohort study.

    PubMed

    Murayama, Hiroshi; Nishi, Mariko; Matsuo, Eri; Nofuji, Yu; Shimizu, Yumiko; Taniguchi, Yu; Fujiwara, Yoshinori; Shinkai, Shoji

    2013-12-01

    Little is known regarding the longitudinal effects of bonding and bridging social capital on health. This study examined the longitudinal associations of bonding and bridging social capital with self-rated health, depressive mood, and cognitive decline in community-dwelling older Japanese. Data analyzed in this study were from the 2010 (baseline) and 2012 (follow-up) Hatoyama Cohort Study. Bonding social capital was assessed by individual perception of homogeneity of the neighborhood (the level of homogeneity among neighbors) and of networks (the amount of homogeneous personal networks) in relation to age, gender, and socioeconomic status. Bridging social capital was assessed by individual perception of heterogeneity of networks (the amount of heterogeneous personal networks) in relation to age, gender, and socioeconomic status. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the effects of baseline social capital on poor health outcome at follow-up by logistic regression analysis. In total, 681 people completed baseline and follow-up surveys. The mean age of participants was 71.8 ± 5.1 years, and 57.9% were male. After adjusting for sociodemographics, lifestyle factors, comorbidity, functional capacity, baseline score of each outcome, and other bonding/bridging social capital, stronger perceived neighborhood homogeneity was inversely associated with poor self-rated health (OR = 0.55, 95% CI = 0.30-1.00) and depressive mood assessed by the Geriatric Depression Scale (OR = 0.58, 95% CI = 0.34-0.99). When participants who reported a depressive mood at baseline were excluded, stronger perceived heterogeneous network was inversely associated with depressive mood (OR = 0.40, 95% CI = 0.19-0.87). Neither bonding nor bridging social capital was significantly associated with cognitive decline assessed by the Mini-Mental State Examination. In conclusion, bonding and bridging social capital affect health in different ways, but they both have

  18. Factors Affecting Medical Service Quality.

    PubMed

    Mosadeghrad, Ali Mohammad

    2014-02-01

    A better understanding of factors influencing quality of medical service can pinpoint better strategies for quality assurance in medical services. This study aimed to identify factors affecting the quality of medical services provided by Iranian physicians. Exploratory in-depth individual interviews were conducted with sixty-four physicians working in various medical institutions in Iran. Individual, organizational and environmental factors enhance or inhibit the quality of medical services. Quality of medical services depends on the personal factors of the physician and patient, and factors pertaining to the healthcare setting and the broader environment. Differences in internal and external factors such as availability of resources, patient cooperation and collaboration among providers affect the quality of medical services and patient outcomes. Supportive leadership, proper planning, education and training and effective management of resources and processes improve the quality of medical services. This article contributes to healthcare theory and practice by developing a conceptual framework for understanding factors that influence medical services quality.

  19. Parental bonding in males with adjustment disorder and hyperventilation syndrome

    PubMed Central

    2012-01-01

    Background The purpose of the study was to identify the style of parental bonding and the personality characteristics that might increase the risk of hyperventilation and adjustment disorder. Methods A total of 917 males were recruited, 156 with adjustment disorder and hyperventilation syndrome (AD + HY), 273 with adjustment disorder without hyperventilation syndrome (AD–HY), and 488 healthy controls. All participants completed the Parental Bonding Instrument, Eysenck Personality Questionnaire, and Chinese Health Questionnaire. Results Analysis using structural equation models identified a pathway relationship in which parental bonding affected personality characteristics, personality characteristics affected mental health condition, and mental health condition affected the development of hyperventilation or adjustment disorder. Males with AD–HY perceived less paternal care, and those with AD + HY perceived more maternal protection than those with adjustment disorder and those in the control group. Participants with AD–HY were more neurotic and less extroverted than those with AD + HY. Both groups showed poorer mental health than the controls. Conclusions Although some patients with hyperventilation syndrome demonstrated symptoms of adjustment disorder, there were different predisposing factors between the two groups in terms of parental bonding and personality characteristics. This finding is important for the early intervention and prevention of hyperventilation and adjustment disorder. PMID:22672223

  20. Nanostructure formation during accumulative roll bonding of commercial purity titanium

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

    Karimi, Mohsen, E-mail: m.karimi@shahroodut.ac.ir

    2016-12-15

    In this investigation, commercial purity titanium (CP–Ti) was subjected to accumulative roll bonding (ARB) process up to 8 cycles (equivalent strain of 6.4) at the ambient temperature. Transmission electron microscopy (TEM) and X–ray diffraction line profile analysis (XRDLPA) were utilized to investigate the microstructure and grain size evolution. Both characterization techniques could clarify the non–uniform microstructure in the early stages and the uniform microstructure in the final stages of the process. The effectiveness of ARB for the fabrication of the nano–grained structure in CP–Ti was revealed. It was found that the SFE is not the only factor affecting grain refinement,more » as compared with other studies on ARB of FCC materials. Influence of other factors such as the melting temperature and the crystalline structure of the material was determined on the grain refinement. - Highlights: •Nano–grained commercial purity titanium was produced by accumulative roll bonding. •TEM and XRDLPA were used for the characterization of the microstructure. •Important factors affecting the grain size of ARBed materials were discussed.« less

  1. Ether bond effects in quaternary ammonium and phosphonium ionic liquid-propanol solutions

    NASA Astrophysics Data System (ADS)

    Kishimura, Hiroaki; Kohki, Erica; Nakada, Ayumu; Tamatani, Kentaro; Abe, Hiroshi

    2018-03-01

    The liquid-liquid equilibria (LLE) of quaternary ammonium and phosphonium ionic liquid (IL)-propanol solutions were examined. The ILs contained cations with or without ether bonds; the anion in all the ILs was bis(trifluoromethanesulfonyl)imide (TFSI-). The cations without ether groups are tributylmethyl ammonium (N4441+), triethylpentyl phosphonium (P2225+), triethyloctyl phosphonium (P2228+), and tributylmethyl phosphonium (P4441+). The cations containing ether groups are N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium, (N122(2O1)+), triethyl(methoxymethyl) phosphonium (P222(1O1)+), and triethyl(2-methoxyethyl) phosphonium, (P222(2O1)+). Propanol isomer effect was observed to affect the LLEs, reflecting the geometrical factors and hydrophobicities of 1-propanol and 2-propanol. According to Raman spectroscopy, the TFSI- anion conformers in the mixtures were altered in the presence of ether bonds in the cations. The universal quasichemical (UNIQUAC) interaction parameters are consistent with significant factors affecting IL-propanol solutions, such as the type of cation (ammonium or phosphonium), ether bonds, TFSI- conformers, and propanol isomer effects.

  2. Bonding with Your Baby

    MedlinePlus

    ... for intimate relationships and foster a sense of security and positive self-esteem . And parents' responsiveness to an infant's signals can affect the child's social and cognitive development. Why Is Bonding Important? Bonding is essential for a baby. Studies of ...

  3. Wafer-to-wafer bonding of nonplanarized MEMS surfaces using solder

    NASA Astrophysics Data System (ADS)

    Sparks, D.; Queen, G.; Weston, R.; Woodward, G.; Putty, M.; Jordan, L.; Zarabadi, S.; Jayakar, K.

    2001-11-01

    The fabrication and reliability of a solder wafer-to-wafer bonding process is discussed. Using a solder reflow process allows vacuum packaging to be accomplished with unplanarized complementary metal-oxide semiconductor (CMOS) surface topography. This capability enables standard CMOS processes, and integrated microelectromechanical systems devices to be packaged at the chip-level. Alloy variations give this process the ability to bond at lower temperatures than most alternatives. Factors affecting hermeticity, shorts, Q values, shifting cavity pressure, wafer saw cleanliness and corrosion resistance will be covered.

  4. Can 1% chlorhexidine diacetate and ethanol stabilize resin-dentin bonds?

    PubMed Central

    Manso, Adriana Pigozzo; Grande, Rosa Helena Miranda; Bedran-Russo, Ana Karina; Reis, Alessandra; Loguercio, Alessandro D.; Pashley, David Henry; Carvalho, Ricardo Marins

    2014-01-01

    Objectives To examine the effects of the combined use of chlorhexidine and ethanol on the durability of resin-dentin bonds. Methods Forty-eight flat dentin surfaces were etched (32% phosphoric acid), rinsed (15 s) and kept wet until bonding procedures. Dentin surfaces were blot-dried with absorbent paper and re-wetted with water (Water, control), 1% chlorhexidine diacetate in water (CHD/Water), 100% ethanol (Ethanol), or 1% chlorhexidine diacetate in ethanol (CHD/Ethanol) solutions for 30 s. They were then bonded with All Bond 3 (AB3, Bisco) or Excite (EX, Ivoclar-Vivadent) using a smooth, continuous rubbing application (10 s), followed by 15 s gentle air stream to evaporate solvents. The adhesives were light-cured (20 s) and resin composite build-ups constructed for the microtensile method. Bonded beams were obtained and tested after 24-hours, 6-months and 15-months of water storage at 37°C. Storage water was changed every month. Effects of treatment and testing periods were analyzed (ANOVA, Holm-Sidak, p<0.05) for each adhesive. Results There were no interactions between factors for both etch-and-rinse adhesives. AB3 was significantly affected only by storage (p = 0.003). Excite was significantly affected only by treatments (p = 0.048). AB3 treated either with ethanol or CHD/ethanol resulted in reduced bond strengths after 15 months. The use of CHD/ethanol resulted in higher bond strengths values for Excite. Conclusions Combined use of ethanol/1% chlorhexidine diacetate did not stabilize bond strengths after 15 months. PMID:24815823

  5. School-Related Factors Affecting High School Seniors' Methamphetamine Use

    ERIC Educational Resources Information Center

    Stanley, Jarrod M.; Lo, Celia C.

    2009-01-01

    Data from the 2005 Monitoring the Future survey were used to examine relationships between school-related factors and high school seniors' lifetime methamphetamine use. The study applied logistic regression techniques to evaluate effects of social bonding variables and social learning variables on likelihood of lifetime methamphetamine use. The…

  6. The Effects of Silicone Contamination on Bond Performance of Various Bond Systems

    NASA Technical Reports Server (NTRS)

    Anderson, G. L.; Stanley, S. D.; Young, G. L.; Brown, R. A.; Evans, K. B.; Wurth, L. A.

    2012-01-01

    The sensitivity to silicone contamination of a wide variety of adhesive bond systems is discussed. Generalizations regarding factors that make some bond systems more sensitive to contamination than others are inferred and discussed. The effect of silane adhesion promoting primer on the contamination sensitivity of two epoxy/steel bond systems is also discussed.

  7. Factors Affecting Tocopherol Concentrations in Soybean Seeds.

    PubMed

    Carrera, Constanza S; Seguin, Philippe

    2016-12-21

    Soybean seeds contain several health-beneficial compounds, including tocopherols, which are used by the nutraceutical and functional food industries. Soybean tocopherol concentrations are, however, highly variable. Large differences observed in tocopherol concentrations among soybean genotypes together with the relatively simple biosynthetic pathway involving few genes support the feasibility of selecting for high-tocopherol soybean. Tocopherol concentrations are also highly influenced by environmental factors and field management. Temperature during seed filling and soil moisture appear to be the main factors affecting tocopherol concentrations; other factors such as soil fertility and solar radiation also affect concentrations and composition. Field management decisions including seeding date, row spacing, irrigation, and fertilization also affect tocopherols. Knowledge of factors affecting soybean tocopherols is essential to develop management strategies that will lead to the production of seeds with consistent target concentrations that will meet the needs of the nutraceutical and functional food industries.

  8. An allosteric disulfide bond is involved in enhanced activation of factor XI by protein disulfide isomerase.

    PubMed

    Zucker, M; Seligsohn, U; Yeheskel, A; Mor-Cohen, R

    2016-11-01

    Essentials Reduction of three disulfide bonds in factor (F) XI enhances chromogenic substrate cleavage. We measured FXI activity upon reduction and identified a bond involved in the enhanced activity. Reduction of FXI augments FIX cleavage, probably by faster conversion of FXI to FXIa. The Cys362-Cys482 disulfide bond is responsible for FXI enhanced activation upon its reduction. Background Reduction of factor (F) XI by protein disulfide isomerase (PDI) has been shown to enhance the ability of FXI to cleave its chromogenic substrate. Three disulfide bonds in FXI (Cys118-Cys147, Cys362-Cys482, and Cys321-Cys321) are involved in this augmented activation. Objectives To characterize the mechanisms by which PDI enhances FXI activity. Methods FXI activity was measured following PDI reduction. Thiols that were exposed in FXI after PDI reduction were labeled with 3-(N-maleimidopropionyl)-biocytin (MPB) and detected with avidin. The rate of conversion of FXI to activated FXI (FXIa) following thrombin activation was assessed with western blotting. FXI molecules harboring mutations that disrupt the three disulfide bonds (C147S, C321S, and C482S) were expressed in cells. The antigenicity of secreted FXI was measured with ELISA, and its activity was assessed by the use of a chromogenic substrate. The effect of disulfide bond reduction was analyzed by the use of molecular dynamics. Results Reduction of FXI by PDI enhanced cleavage of both its chromogenic substrate, S2366, and its physiologic substrate, FIX, and resulted in opening of the Cys362-Cys482 bond. The rate of conversion of FXI to FXIa was increased following its reduction by PDI. C482S-FXI showed enhanced activity as compared with both wild-type FXI and C321S-FXI. MD showed that disruption of the Cys362-Cys482 bond leads to a broader thrombin-binding site in FXI. Conclusions Reduction of FXI by PDI enhances its ability to cleave FIX, probably by causing faster conversion of FXI to FXIa. The Cys362-Cys482 disulfide

  9. Web-based Factors Affecting Online Purchasing Behaviour

    NASA Astrophysics Data System (ADS)

    Ariff, Mohd Shoki Md; Sze Yan, Ng; Zakuan, Norhayati; Zaidi Bahari, Ahamad; Jusoh, Ahmad

    2013-06-01

    The growing use of internet and online purchasing among young consumers in Malaysia provides a huge prospect in e-commerce market, specifically for B2C segment. In this market, if E-marketers know the web-based factors affecting online buyers' behaviour, and the effect of these factors on behaviour of online consumers, then they can develop their marketing strategies to convert potential customers into active one, while retaining existing online customers. Review of previous studies related to the online purchasing behaviour in B2C market has point out that the conceptualization and empirical validation of the online purchasing behaviour of Information and Communication Technology (ICT) literate users, or ICT professional, in Malaysia has not been clearly addressed. This paper focuses on (i) web-based factors which online buyers (ICT professional) keep in mind while shopping online; and (ii) the effect of web-based factors on online purchasing behaviour. Based on the extensive literature review, a conceptual framework of 24 items of five factors was constructed to determine web-based factors affecting online purchasing behaviour of ICT professional. Analysis of data was performed based on the 310 questionnaires, which were collected using a stratified random sampling method, from ICT undergraduate students in a public university in Malaysia. The Exploratory factor analysis performed showed that five factors affecting online purchase behaviour are Information Quality, Fulfilment/Reliability/Customer Service, Website Design, Quick and Details, and Privacy/Security. The result of Multiple Regression Analysis indicated that Information Quality, Quick and Details, and Privacy/Security affect positively online purchase behaviour. The results provide a usable model for measuring web-based factors affecting buyers' online purchase behaviour in B2C market, as well as for online shopping companies to focus on the factors that will increase customers' online purchase.

  10. 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.

  11. Structural factors affecting 13C NMR chemical shifts of cellulose: a computational study

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

    Yang, Hui; Wang, Tuo; Oehme, Daniel

    Here, the doublet C4 peaks at ~ 85 and ~ 89 ppm in solid-state 13C NMR spectra of native cellulose have been attributed to signals of C4 atoms on the surface (solvent-exposed) and in the interior of microfibrils, designated as sC4 and iC4, respectively. The relative intensity ratios of sC4 and iC4 observed in NMR spectra of cellulose have been used to estimate the degree of crystallinity of cellulose and the number of glucan chains in cellulose microfibrils. However, the molecular structures of cellulose responsible for the specific surface and interior C4 peaks have not been positively confirmed. Using densitymore » functional theory (DFT) methods and structures produced from classical molecular dynamics simulations, we investigated how the following four factors affect 13C NMR chemical shifts in cellulose: conformations of exocyclic groups at C6 ( tg, gt and gg), H 2O molecules H-bonded on the surface of the microfibril, glycosidic bond angles (Φ, Ψ) and the distances between H4 and HO3 atoms. We focus on changes in the δ 13C4 value because it is the most significant observable for the same C atom within the cellulose structure. DFT results indicate that different conformations of the exocyclic groups at C6 have the greatest influence on δ 13C4 peak separation, while the other three factors have secondary effects that increase the spread of the calculated C4 interior and surface peaks.« less

  12. Structural factors affecting 13C NMR chemical shifts of cellulose: a computational study

    DOE PAGES

    Yang, Hui; Wang, Tuo; Oehme, Daniel; ...

    2017-11-02

    Here, the doublet C4 peaks at ~ 85 and ~ 89 ppm in solid-state 13C NMR spectra of native cellulose have been attributed to signals of C4 atoms on the surface (solvent-exposed) and in the interior of microfibrils, designated as sC4 and iC4, respectively. The relative intensity ratios of sC4 and iC4 observed in NMR spectra of cellulose have been used to estimate the degree of crystallinity of cellulose and the number of glucan chains in cellulose microfibrils. However, the molecular structures of cellulose responsible for the specific surface and interior C4 peaks have not been positively confirmed. Using densitymore » functional theory (DFT) methods and structures produced from classical molecular dynamics simulations, we investigated how the following four factors affect 13C NMR chemical shifts in cellulose: conformations of exocyclic groups at C6 ( tg, gt and gg), H 2O molecules H-bonded on the surface of the microfibril, glycosidic bond angles (Φ, Ψ) and the distances between H4 and HO3 atoms. We focus on changes in the δ 13C4 value because it is the most significant observable for the same C atom within the cellulose structure. DFT results indicate that different conformations of the exocyclic groups at C6 have the greatest influence on δ 13C4 peak separation, while the other three factors have secondary effects that increase the spread of the calculated C4 interior and surface peaks.« less

  13. The coevolution of long-term pair bonds and cooperation.

    PubMed

    Song, Z; Feldman, M W

    2013-05-01

    The evolution of social traits may not only depend on but also change the social structure of the population. In particular, the evolution of pairwise cooperation, such as biparental care, depends on the pair-matching distribution of the population, and the latter often emerges as a collective outcome of individual pair-bonding traits, which are also under selection. Here, we develop an analytical model and individual-based simulations to study the coevolution of long-term pair bonds and cooperation in parental care, where partners play a Snowdrift game in each breeding season. We illustrate that long-term pair bonds may coevolve with cooperation when bonding cost is below a threshold. As long-term pair bonds lead to assortative interactions through pair-matching dynamics, they may promote the prevalence of cooperation. In addition to the pay-off matrix of a single game, the evolutionarily stable equilibrium also depends on bonding cost and accidental divorce rate, and it is determined by a form of balancing selection because the benefit from pair-bond maintenance diminishes as the frequency of cooperators increases. Our findings highlight the importance of ecological factors affecting social bonding cost and stability in understanding the coevolution of social behaviour and social structures, which may lead to the diversity of biological social systems. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  14. Hardness and elasticity of caries-affected and sound primary tooth dentin bonded with 4-META one-step self-etch adhesives

    PubMed Central

    Hosoya, Yumiko; Tay, Franklin R.; Miyakoshi, Shoichi; Pashley, David H.

    2013-01-01

    Purpose This study evaluated the quality of the interface of sound and carious primary tooth dentin bonded with two 4-META one-step self-etch adhesives. Methods Twelve sound and twelve carious primary molars were bonded with AQ Bond Plus (AQBP; Sun Medical) or Hybrid Bond (HB; Sun Medical) and restored with Clearfil Protect Liner F (Kuraray Medical Inc.). After 24 hours of water immersion, the teeth were sectioned and polished. Resin-dentin interfaces were measured with a nano-indentation tester and hardness and Young’s modulus were calculated. Data were analyzed using one-way or two-ways ANOVA and Fisher’s PLSD test with α=0.05. Resin-dentin interfaces were also observed with SEM and TEM. Ammoniacal silver nitrate was used as a tracer for TEM observation. Results Hardness and Young’s modulus of the interfacial dentin were significantly lower than the underlying intact dentin except for the carious-AQBP group. However, there was no significant difference of hardness and Young's moduli of the interfacial dentin among all groups. TEM revealed extensive interfacial nanoleakage in sound dentin bonded with either AQBP or HB. For the carious teeth, nanoleakage was absent in the hybrid layers bonded with the two adhesives. However, extensive silver deposits were identified from the subsurface, porous caries-affected dentin. PMID:18795517

  15. Factors Affecting Wound Healing

    PubMed Central

    Guo, S.; DiPietro, L.A.

    2010-01-01

    Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. For a wound to heal successfully, all four phases must occur in the proper sequence and time frame. Many factors can interfere with one or more phases of this process, thus causing improper or impaired wound healing. This article reviews the recent literature on the most significant factors that affect cutaneous wound healing and the potential cellular and/or molecular mechanisms involved. The factors discussed include oxygenation, infection, age and sex hormones, stress, diabetes, obesity, medications, alcoholism, smoking, and nutrition. A better understanding of the influence of these factors on repair may lead to therapeutics that improve wound healing and resolve impaired wounds. PMID:20139336

  16. Factors affecting wound healing.

    PubMed

    Guo, S; Dipietro, L A

    2010-03-01

    Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. For a wound to heal successfully, all four phases must occur in the proper sequence and time frame. Many factors can interfere with one or more phases of this process, thus causing improper or impaired wound healing. This article reviews the recent literature on the most significant factors that affect cutaneous wound healing and the potential cellular and/or molecular mechanisms involved. The factors discussed include oxygenation, infection, age and sex hormones, stress, diabetes, obesity, medications, alcoholism, smoking, and nutrition. A better understanding of the influence of these factors on repair may lead to therapeutics that improve wound healing and resolve impaired wounds.

  17. Factors Affecting Sign Retroreflectivity : final report.

    DOT National Transportation Integrated Search

    2001-01-01

    This study was undertaken to better understand the factors that may affect road sign retroreflectivity, specifically age and physical orientation. A better understanding of these factors could provide guidance to ODOT in managing its inventory of roa...

  18. Effect of Casein Phosphopeptide-amorphous Calcium Phosphate Treatment on Microtensile Bond Strength to Carious Affected Dentin Using Two Adhesive Strategies

    PubMed Central

    Bahari, Mahmoud; Savadi Oskoee, Siavash; Kimyai, Soodabeh; Pouralibaba, Firoz; Farhadi, Farrokh; Norouzi, Marouf

    2014-01-01

    Background and aims. The aim was to evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on microtensile bond strength (μTBS) to carious affected dentin (CAD) using etch-and-rinse and self-etch adhesive systems. Materials and methods. The occlusal surface of 32 human molars with moderate occlusal caries was removed. Infected dentin was removed until reaching CAD and the teeth were randomly divided into two groups based on the Single Bond (SB) and Clearfil SE Bond (CSE) adhesive systems. Before composite resin bonding, each group was subdivided into three subgroups of ND, CAD and CPP-ACP-treated CAD (CAD-CPP) based on the dentin substrate. After dissecting samples to l-mm-thick cross-sections (each subgroup: n = 13), μTBS was measured at a strain rate of 0.5 mm/min. Data was analyzed using two-way ANOVA, independent samples t-test and post-hoc Tukey tests (α=0.05). Results. Bond strength of both adhesive systems to ND was significantly higher than that to CAD (P <0.001) and CAD/CPP (P < 0.001). There were no significant differences between the μTBS of SB to CAD and CAD-CPP (P > 0.05).μTBS of CSE to CAD-CPP was higher than that to CAD; however, the difference was not significant (P > 0.05). Significant differences were found between SB and CSE systems only with CAD substrate (P < 0.001). Conclusion. Regardless of the adhesive system used, surface treatment of CAD with CPP-ACP did not have a significant effect on bond strength. However, bond strength to CAD was higher with SB rather than with CSE. PMID:25346832

  19. Social bonds affect anti-predator behaviour in a tolerant species of macaque, Macaca nigra.

    PubMed

    Micheletta, Jérôme; Waller, Bridget M; Panggur, Maria R; Neumann, Christof; Duboscq, Julie; Agil, Muhammad; Engelhardt, Antje

    2012-10-07

    Enduring positive social bonds between individuals are crucial for humans' health and well being. Similar bonds can be found in a wide range of taxa, revealing the evolutionary origins of humans' social bonds. Evidence suggests that these strong social bonds can function to buffer the negative effects of living in groups, but it is not known whether they also function to minimize predation risk. Here, we show that crested macaques (Macaca nigra) react more strongly to playbacks of recruitment alarm calls (i.e. calls signalling the presence of a predator and eliciting cooperative mobbing behaviour) if they were produced by an individual with whom they share a strong social bond. Dominance relationships between caller and listener had no effect on the reaction of the listener. Thus, strong social bonds may improve the coordination and efficiency of cooperative defence against predators, and therefore increase chances of survival. This result broadens our understanding of the evolution and function of social bonds by highlighting their importance in the anti-predator context.

  20. Social bonds affect anti-predator behaviour in a tolerant species of macaque, Macaca nigra

    PubMed Central

    Micheletta, Jérôme; Waller, Bridget M.; Panggur, Maria R.; Neumann, Christof; Duboscq, Julie; Agil, Muhammad; Engelhardt, Antje

    2012-01-01

    Enduring positive social bonds between individuals are crucial for humans' health and well being. Similar bonds can be found in a wide range of taxa, revealing the evolutionary origins of humans' social bonds. Evidence suggests that these strong social bonds can function to buffer the negative effects of living in groups, but it is not known whether they also function to minimize predation risk. Here, we show that crested macaques (Macaca nigra) react more strongly to playbacks of recruitment alarm calls (i.e. calls signalling the presence of a predator and eliciting cooperative mobbing behaviour) if they were produced by an individual with whom they share a strong social bond. Dominance relationships between caller and listener had no effect on the reaction of the listener. Thus, strong social bonds may improve the coordination and efficiency of cooperative defence against predators, and therefore increase chances of survival. This result broadens our understanding of the evolution and function of social bonds by highlighting their importance in the anti-predator context. PMID:22859593

  1. Bond Sensitivity to Silicone Contamination

    NASA Technical Reports Server (NTRS)

    Caldwell, G. A.; Hudson, W. D.; Hudson, W. D.; Cash, Stephen F. (Technical Monitor)

    2003-01-01

    Currently during fabrication of the Space Shuttle booster rocket motors, the use of silicone and silicone-containing products is prohibited in most applications. Many shop aids and other materials containing silicone have the potential, if they make contact with a bond surface, to transfer some of the silicone to the substrates being bonded. Such transfer could result in a reduction of the bond strength or even failure of the subsequent bonds. This concern is driving the need to understand the effect of silicones and the concentration needed to affect a given bond-line strength. Additionally, as silicone detection methods used for materials acceptance improve what may have gone unnoticed earlier is now being detected. Thus, realistic silicone limits for process materials (below which bond performance is satisfactory) are needed rather than having an absolute no silicone permitted policy.

  2. How Is the Enamel Affected by Different Orthodontic Bonding Agents and Polishing Techniques?

    PubMed

    Heravi, Farzin; Shafaee, Hooman; Abdollahi, Mojtaba; Rashed, Roozbeh

    2015-03-01

    The objective of this study was to assess the effect of new bonding techniques on enamel surface. Sixty upper central incisors were randomly divided into two equal groups. In the first group, metal brackets were bonded using TransbondXT and, in the second group, the same brackets were bonded with Maxcem Elite. The shear bond strength (SBS) of both agents to enamel was measured and the number and length of enamel cracks before bonding, after debonding and after polishing were compared. The number of visible cracks and the adhesive remnant index (ARI) scores in each group were also measured. There were significantly more enamel cracks in the Transbond XT group after debonding and polishing compared to the Maxcem Elite group. There was no significant difference in the length of enamel cracks between the two groups; but, in each group, a significant increase in the length of enamel cracks was noticeable after debonding. Polishing did not cause any statistically significant change in crack length. The SBS of Maxcem Elite was significantly lower than that of Transbond XT (95% confidence interval). Maxcem Elite offers clinically acceptable bond strength and can thus be used as a routine adhesive for orthodontic purposes since it is less likely to damage the enamel.

  3. Age Learning Factors Affecting Pilot Education.

    ERIC Educational Resources Information Center

    Torbert, Brison

    This document, intended for pilot education and flight safety specialists, consists chiefly of a review of the literature on physiological factors that affect pilot education and an examination of environmental factors that should be scrutinized in order to improve the effectiveness of aviation learning facilities. The physiological factors…

  4. Bond-Slip Relationship for CFRP Sheets Externally Bonded to Concrete under Cyclic Loading.

    PubMed

    Li, Ke; Cao, Shuangyin; Yang, Yue; Zhu, Juntao

    2018-02-26

    The objective of this paper was to explore the bond-slip relationship between carbon fiber-reinforced polymer (CFRP) sheets and concrete under cyclic loading through experimental and analytical approaches. Modified beam tests were performed in order to gain insight into the bond-slip relationship under static and cyclic loading. The test variables are the CFRP-to-concrete width ratio, and the bond length of the CFRP sheets. An analysis of the test results in this paper and existing test results indicated that the slope of the ascending segment of the bond-slip curve decreased with an increase in the number of load cycles, but the slip corresponding to the maximum shear stress was almost invariable as the number of load cycles increased. In addition, the rate of reduction in the slope of the ascending range of the bond-slip curve during cyclic loading decreased as the concrete strength increased, and increased as the load level or CFRP-to-concrete width ratio enhanced. However, these were not affected by variations in bond length if the residual bond length was longer than the effective bond length. A bilinear bond-slip model for CFRP sheets that are externally bonded to concrete under cyclic loading, which considered the effects of the cyclic load level, concrete strength, and CFRP-to-concrete ratio, was developed based on the existing static bond-slip model. The accuracy of this proposed model was verified by a comparison between this proposed model and test results.

  5. Nanoleakage of dentin adhesive systems bonded to Carisolv-treated dentin.

    PubMed

    Kubo, Shisei; Li, Heping; Burrow, Michael F; Tyas, Martin J

    2002-01-01

    The hybrid layer created in caries-affected dentin has not been fully elucidated and may influence bond durability. This study investigated the nanoleakage patterns of caries-affected dentin after excavation with Carisolv or conventional instruments treated with one of three adhesive systems. Flat occlusal dentin surfaces, including carious lesions, were prepared from extracted human molars and finished with wet 600-grit silicon carbide paper. Carious dentin was removed with Carisolv or round steel burs in conjunction with Caries Detector. PermaQuik, Single Bond or One-Up Bond F was bonded to the excavated dentin surfaces and adjacent flat occlusal surfaces and it was covered with Silux Plus resin-based composite. After 24-hour storage in 37 degrees C water, the bonded interfaces were polished to remove flash, and the surrounding tooth surfaces were coated with nail varnish. Specimens were immersed in 50% (w/v) silver nitrate solution for 24 hours, exposed to photo developing solution for eight hours, then sectioned longitudinally through the bonded, excavated dentin or "normal" dentin surfaces. The sectioned surfaces were polished, carbon coated and observed in a Field Emission-SEM using back scattered electrons. Silver deposition occurred along the base of the hybrid layer for all specimens. However, Single Bond showed a greater density of silver deposition in the caries-affected dentin compared with normal dentin. PermaQuik had a thicker hybrid layer in caries-affected dentin than normal dentin. One-Up Bond F exhibited a thin hybrid layer in normal dentin, but the hybrid layer was often difficult to detect in caries-affected dentin.

  6. Factors that lead to failure with wood adhesive bonds

    Treesearch

    Charles R. Frihart; James F. Beecher

    2016-01-01

    Understanding what makes a good wood adhesive is difficult since the type of adhesive, wood species, bonding process, and resultant products vary considerably. Wood bonds are subjected to a variety of tests that reflect the different product performance criteria in diverse countries. The most common tests involve some type of moisture resistance; both wood and adhesive...

  7. Social bonding: regulation by neuropeptides.

    PubMed

    Lieberwirth, Claudia; Wang, Zuoxin

    2014-01-01

    Affiliative social relationships (e.g., among spouses, family members, and friends) play an essential role in human society. These relationships affect psychological, physiological, and behavioral functions. As positive and enduring bonds are critical for the overall well-being of humans, it is not surprising that considerable effort has been made to study the neurobiological mechanisms that underlie social bonding behaviors. The present review details the involvement of the nonapeptides, oxytocin (OT), and arginine vasopressin (AVP), in the regulation of social bonding in mammals including humans. In particular, we will discuss the role of OT and AVP in the formation of social bonds between partners of a mating pair as well as between parents and their offspring. Furthermore, the role of OT and AVP in the formation of interpersonal bonding involving trust is also discussed.

  8. Environmental Factors Affecting Preschoolers' Motor Development

    ERIC Educational Resources Information Center

    Venetsanou, Fotini; Kambas, Antonis

    2010-01-01

    The process of development occurs according to the pattern established by the genetic potential and also by the influence of environmental factors. The aim of the present study was to focus on the main environmental factors affecting motor development. The review of the literature revealed that family features, such as socioeconomic status,…

  9. Rapid adhesive bonding of advanced composites and titanium

    NASA Technical Reports Server (NTRS)

    Stein, B. A.; Tyeryart, J. R.; Hodgest, W. T.

    1985-01-01

    Rapid adhesive bonding (RAB) concepts utilize a toroid induction technique to heat the adhesive bond line directly. This technique was used to bond titanium overlap shear specimens with 3 advanced thermoplastic adhesives and APC-2 (graphite/PEEK) composites with PEEK film. Bond strengths equivalent to standard heated-platen press bonds were produced with large reductions in process time. RAB produced very strong bonds in APC-2 adherend specimens; the APC-2 adherends were highly resistant to delamination. Thermal cycling did not significantly affect the shear strengths of RAB titanium bonds with polyimide adhesives. A simple ultrasonic non-destructive evaluation process was found promising for evaluating bond quality.

  10. Effect of blood and saliva contamination on bond strength of brackets bonded with a protective liquid polish and a light-cured adhesive.

    PubMed

    Sayinsu, Korkmaz; Isik, Fulya; Sezen, Serdar; Aydemir, Bulent

    2007-03-01

    The application of a polymer coating to the labial enamel tooth surface before bonding can help keep white spot lesions from forming. Previous studies evaluating the effects of blood and saliva contamination on the bond strengths of light-cured composites showed significant reductions in bond strength values. The purpose of this study was to investigate whether the bond strength of a light-cured system (Transbond XT, 3M Unitek, Puchheim, Germany) used with a liquid polish (BisCover, Bisco, Schaumburg, Ill) is affected by contamination with blood or saliva. One hundred twenty permanent human premolars were randomly divided into 6 groups of 20. Various enamel surface conditions were studied: dry, blood contaminated, and saliva contaminated. A light-cured bonding system (Transbond XT) was used in all groups. The teeth in group 1 were bonded with Transbond XT. In the second group, BisCover polymeric resin polish was applied on the etched tooth surfaces before the brackets were bonded with Transbond XT resin. Comparison of the first and second groups showed no statistically significant difference. Groups 3 through 6 were bonded without Transbond XT. For groups 3 and 5, a layer of blood or saliva, respectively, was applied to the etched enamel followed by BisCover. In groups 4 and 6, blood or saliva, respectively, was applied on the light-cured BisCover. Shear forces were applied to the samples with a universal testing machine, and bond strengths were measured in megapascals. The protective liquid polish (BisCover) layer did not affect bond strength. Blood contamination on acid-etched surfaces affects bond strength more than saliva contamination. When a protective liquid polish (BisCover) is applied to the tooth surface, the effect of contamination by blood or saliva is prevented.

  11. Nutritional Factors Affecting Adult Neurogenesis and Cognitive Function.

    PubMed

    Poulose, Shibu M; Miller, Marshall G; Scott, Tammy; Shukitt-Hale, Barbara

    2017-11-01

    Adult neurogenesis, a complex process by which stem cells in the hippocampal brain region differentiate and proliferate into new neurons and other resident brain cells, is known to be affected by many intrinsic and extrinsic factors, including diet. Neurogenesis plays a critical role in neural plasticity, brain homeostasis, and maintenance in the central nervous system and is a crucial factor in preserving the cognitive function and repair of damaged brain cells affected by aging and brain disorders. Intrinsic factors such as aging, neuroinflammation, oxidative stress, and brain injury, as well as lifestyle factors such as high-fat and high-sugar diets and alcohol and opioid addiction, negatively affect adult neurogenesis. Conversely, many dietary components such as curcumin, resveratrol, blueberry polyphenols, sulforaphane, salvionic acid, polyunsaturated fatty acids (PUFAs), and diets enriched with polyphenols and PUFAs, as well as caloric restriction, physical exercise, and learning, have been shown to induce neurogenesis in adult brains. Although many of the underlying mechanisms by which nutrients and dietary factors affect adult neurogenesis have yet to be determined, nutritional approaches provide promising prospects to stimulate adult neurogenesis and combat neurodegenerative diseases and cognitive decline. In this review, we summarize the evidence supporting the role of nutritional factors in modifying adult neurogenesis and their potential to preserve cognitive function during aging. © 2017 American Society for Nutrition.

  12. Transforming individual civic engagement into community collective efficacy: the role of bonding social capital.

    PubMed

    Collins, Charles R; Neal, Jennifer Watling; Neal, Zachary P

    2014-12-01

    Collective efficacy is defined as residents' perceived collective capacity to take coordinated and interdependent action on issues that affect their lives. This study explored factors associated with neighborhood collective efficacy among residents. Utilizing a national sample of 4,120 urban households provided by Annie E. Casey Foundation's Making Connection Initiative, we investigated the mediating role of residents' perceptions of bonding social capital (i.e. reciprocity, trust, and shared norms) in the association between civic engagement and collective efficacy. Multiple regression analyses revealed that civic engagement and bonding social capital were both directly related to collective efficacy. Additionally, bonding social capital partially mediated the relationship between civic engagement and collective efficacy. Specifically, residents who reported greater levels of civic engagement also reported higher levels of bonding social capital. In turn, residents who reported higher levels of bonding social capital also reported higher levels of neighborhood collective efficacy. We discuss implications of these findings for researchers and practitioners interested in associations of neighborhood collective efficacy.

  13. 27 CFR 19.168 - Superseding bonds.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Superseding bonds. 19.168 Section 19.168 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Circular 570. TTB may also require the filing of a superseding bond if any other contingency affecting the...

  14. 27 CFR 19.168 - Superseding bonds.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Superseding bonds. 19.168 Section 19.168 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... Circular 570. TTB may also require the filing of a superseding bond if any other contingency affecting the...

  15. Factors affecting dignity of patients with multiple sclerosis.

    PubMed

    Sharifi, Simin; Borhani, Fariba; Abbaszadeh, Abbas

    2016-12-01

    MS is one of the most common chronic diseases of the nervous system. Apart from disease progression, other complications such as unemployment, separation and divorce could potentially threat patients' dignity. Most of the previous studies have been done of maintaining patients' dignity in interaction with healthcare team, but studies on affecting factors of dignity in chronic patients in the society and in interaction with usual people are scarce. We aimed to investigate factors affecting dignity of Iranian patients with MS in daily living and in interaction of them with the society. In this qualitative study, 13 patients with multiple sclerosis were chosen by purposive sampling and semi-structured interviews were conducted until data saturation. The study was done in Tehran, the capital city of Iran. Factors affecting dignity were classified as 'personal factors' and 'social factors'. Personal factors consist of the following subcategories: patients' communication with self, patients' knowledge, patients' values and beliefs and patients' resources. Social factors include others' communication with patients, social knowledge, social values and beliefs and social resources. Multiple personal and social factors interfere in perceived patient dignity. In fact, interaction between personal and social factors can be influential in final perceived dignity. By focusing on whole aspects of the patients' lives, we can identify dignity-promoting or dignity-threatening factors and help patients maintain their dignity by taking appropriate measures for moderating threatening factors and improving dignity enhancing ones. © 2016 Nordic College of Caring Science.

  16. Effect of Bonding Agent Application Method on Titanium-Ceramic Bond Strength.

    PubMed

    Curtis, Joseph G; Dossett, Jon; Prihoda, Thomas J; Teixeira, Erica C

    2015-07-01

    Although milled titanium may be used as a substructure in fixed and implant prosthodontics, the application of the veneering porcelain presents particular challenges compared to traditional alloys. To address these challenges, some Ti ceramic systems incorporate the application of a bonding agent prior to the opaque layer. Vita Titankeramik's bonding agent is available as a powder, paste, and spray-on formulation. We examined the effect of these three application methods on the bond strength. Four titanium bars were milled from each of 11 wafers cut from grade II Ti using the Kavo Everest milling unit and a custom-designed milling toolpath. An experienced technician prepared the 25 × 3 × 0.5 mm(3) metal bars and applied bonding agent using one of three application methods, and then applied opaque, dentin, and enamel porcelains according to manufacturer's instructions to a 8 × 3 × 1 mm(3) porcelain. A control group received no bonding agent prior to porcelain application. The four groups (n = 11) were blindly tested for differences in bond strength using a universal testing machine in a three-point bend test configuration, based on ISO 9693-1:2012. The average (SD) bond strengths for the control, powder, paste, and spray-on groups, respectively, were: 24.8 (2.6), 24.6 (2.6), 25.3 (4.0), and 24.1 (3.9) MPa. One-way ANOVA and Tukey's multiple comparison tests were performed between all groups. There were no statistically significant differences among groups (p = 0.951). Titanium-porcelain bond strength was not affected by the use of a bonding agent or its application method when tested by ISO 9693-1 standard. © 2014 by the American College of Prosthodontists.

  17. Prediction of allosteric sites and mediating interactions through bond-to-bond propensities

    NASA Astrophysics Data System (ADS)

    Amor, B. R. C.; Schaub, M. T.; Yaliraki, S. N.; Barahona, M.

    2016-08-01

    Allostery is a fundamental mechanism of biological regulation, in which binding of a molecule at a distant location affects the active site of a protein. Allosteric sites provide targets to fine-tune protein activity, yet we lack computational methodologies to predict them. Here we present an efficient graph-theoretical framework to reveal allosteric interactions (atoms and communication pathways strongly coupled to the active site) without a priori information of their location. Using an atomistic graph with energy-weighted covalent and weak bonds, we define a bond-to-bond propensity quantifying the non-local effect of instantaneous bond fluctuations propagating through the protein. Significant interactions are then identified using quantile regression. We exemplify our method with three biologically important proteins: caspase-1, CheY, and h-Ras, correctly predicting key allosteric interactions, whose significance is additionally confirmed against a reference set of 100 proteins. The almost-linear scaling of our method renders it suitable for high-throughput searches for candidate allosteric sites.

  18. Prediction of allosteric sites and mediating interactions through bond-to-bond propensities

    PubMed Central

    Amor, B. R. C.; Schaub, M. T.; Yaliraki, S. N.; Barahona, M.

    2016-01-01

    Allostery is a fundamental mechanism of biological regulation, in which binding of a molecule at a distant location affects the active site of a protein. Allosteric sites provide targets to fine-tune protein activity, yet we lack computational methodologies to predict them. Here we present an efficient graph-theoretical framework to reveal allosteric interactions (atoms and communication pathways strongly coupled to the active site) without a priori information of their location. Using an atomistic graph with energy-weighted covalent and weak bonds, we define a bond-to-bond propensity quantifying the non-local effect of instantaneous bond fluctuations propagating through the protein. Significant interactions are then identified using quantile regression. We exemplify our method with three biologically important proteins: caspase-1, CheY, and h-Ras, correctly predicting key allosteric interactions, whose significance is additionally confirmed against a reference set of 100 proteins. The almost-linear scaling of our method renders it suitable for high-throughput searches for candidate allosteric sites. PMID:27561351

  19. Effect of light aging on silicone-resin bond strength in maxillofacial prostheses.

    PubMed

    Polyzois, Gregory; Pantopoulos, Antonis; Papadopoulos, Triantafillos; Hatamleh, Muhanad

    2015-04-01

    The aim of this study was to investigate the effect of accelerated light aging on bond strength of a silicone elastomer to three types of denture resin. A total of 60 single lap joint specimens were fabricated with auto-, heat-, and photopolymerized (n = 20) resins. An addition-type silicone elastomer (Episil-E) was bonded to resins treated with the same primer (A330-G). Thirty specimens served as controls and were tested after 24 hours, and the remaining were aged under accelerated exposure to daylight for 546 hours (irradiance 765 W/m(2) ). Lap shear joint tests were performed to evaluate bond strength at 50 mm/min crosshead speed. Two-way ANOVA and Tukey's test were carried out to detect statistical significance (p < 0.05). ANOVA showed that the main effect of light aging was the most important factor determining the shear bond strength. The mean bond strength values ranged from 0.096 to 0.136 MPa. The highest values were recorded for auto- (0.131 MPa) and photopolymerized (0.136 MPa) resins after aging. Accelerated light aging for 546 hours affects the bond strength of an addition-type silicone elastomer to three different denture resins. The bond strength significantly increased after aging for photo- and autopolymerized resins. All the bonds failed adhesively. © 2014 by the American College of Prosthodontists.

  20. Automated optical inspection of liquid crystal display anisotropic conductive film bonding

    NASA Astrophysics Data System (ADS)

    Ni, Guangming; Du, Xiaohui; Liu, Lin; Zhang, Jing; Liu, Juanxiu; Liu, Yong

    2016-10-01

    Anisotropic conductive film (ACF) bonding is widely used in the liquid crystal display (LCD) industry. It implements circuit connection between screens and flexible printed circuits or integrated circuits. Conductive microspheres in ACF are key factors that influence LCD quality, because the conductive microspheres' quantity and shape deformation rate affect the interconnection resistance. Although this issue has been studied extensively by prior work, quick and accurate methods to inspect the quality of ACF bonding are still missing in the actual production process. We propose a method to inspect ACF bonding effectively by using automated optical inspection. The method has three steps. The first step is that it acquires images of the detection zones using a differential interference contrast (DIC) imaging system. The second step is that it identifies the conductive microspheres and their shape deformation rate using quantitative analysis of the characteristics of the DIC images. The final step is that it inspects ACF bonding using a back propagation trained neural network. The result shows that the miss rate is lower than 0.1%, and the false inspection rate is lower than 0.05%.

  1. 12 CFR 713.4 - What bond forms may be used?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....4 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS FIDELITY BOND AND INSURANCE COVERAGE FOR FEDERAL CREDIT UNIONS § 713.4 What bond forms may be used? (a) A... basic bond form; or (2) Any rider or endorsement that limits coverage of approved basic bond forms. [64...

  2. Oxytocin and Social Bonds: The Role of Oxytocin in Perceptions of Romantic Partners' Bonding Behavior.

    PubMed

    Algoe, Sara B; Kurtz, Laura E; Grewen, Karen

    2017-12-01

    In this research, we tested hypotheses about the role of oxytocin in adult human bonding. Inspired by revisiting the research on pair bonding in microtine voles that fueled psychologists' interest in the role of oxytocin in social life, we drew on recent theory from affective and relationship science to identify a well-defined bonding context for human romantic relationships. We then paired these behaviors and subjective psychological responses with a measure of naturally circulating oxytocin. In 129 romantically involved adults whose partner expressed gratitude to them in the lab, greater oxytocin over the prior 24 hr was associated with greater perceptions of the expresser's responsiveness and gratitude, as well as greater experienced love, but not general affective reward. Moreover, in this one-time conversation, higher oxytocin acted like rose-colored glasses, attenuating the effect of a partner's behaviorally coded expressive behavior on perceptions of the expresser's responsiveness. These results justify future research on the role of oxytocin in psychological aspects of growth processes.

  3. Effect of different intracoronal bleaching methods on shear bond strength of ceramic brackets bonded to bleached enamel: An in-vitro study.

    PubMed

    Chauhan, Vikas; Kumar, Piush; Sharma, Payal; Shetty, Divya

    2017-01-01

    To investigate the effect of different intracoronal bleaching methods on the shear bond strength and site of failure of ceramic brackets. Sixty freshly extracted human maxillary incisors were randomly divided into four groups ( n = 15). Endodontic access cavity was prepared and root canals were filled, root fillings were removed 2mm apical to the cementoenamel junction, and a 2-mmthick layer of glass ionomer cement base was applied. Group 1 served as the control. Intracoronal bleaching was performed with 35% carbamide peroxide in group 2, sodium perborate in group 3, and 37.5% hydrogen peroxide in group 4. The teeth were immersed in artificial saliva for 4 weeks before bracket bonding. Ceramic brackets were bonded with composite resin and cured with LED light. After bonding, the shear bond strength of the brackets was tested with a universal testing machine. The site of bond failure was determined by modified ARI (Adhesive Remnant Index). The highest value of shear bond strength was measured in control group (18.67 ± 1.59 MPa), which was statistically significant from groups 2,3, and 4. There was no significant difference between groups 2 and 4. The lowest shear bond strength was measured in group 3. ARI scores were not significant from each other. Intracoronal bleaching significantly affected the shear bond strength of ceramic brackets even after 4 weeks of bleaching. Bleaching with sodium perborate affects shear bond strength more adversely than does bleaching with other agents like hydrogen peroxide and carbamide peroxide.

  4. Bent Bonds and Multiple Bonds.

    ERIC Educational Resources Information Center

    Robinson, Edward A.; Gillespie, Ronald J.

    1980-01-01

    Considers carbon-carbon multiple bonds in terms of Pauling's bent bond model, which allows direct calculation of double and triple bonds from the length of a CC single bond. Lengths of these multiple bonds are estimated from direct measurements on "bent-bond" models constructed of plastic tubing and standard kits. (CS)

  5. Microshear bond strength of resin composite to teeth affected by molar hypomineralization using 2 adhesive systems.

    PubMed

    William, Vanessa; Burrow, Michael F; Palamara, Joseph E A; Messer, Louise B

    2006-01-01

    When restoring hypomineralized first permanent molars, placement of cavo-surface margins can be difficult to ascertain due to uncertainty of the bonding capability of the tooth surface. The purpose of this study was to investigate the adhesion of resin composite bonded to control and hypomineralized enamel with an all-etch single-bottle adhesive or self-etching primer adhesive. Specimens of control enamel (N=44) and hypomineralized enamel (N=45) had a 0.975-mm diameter composite rod (Filtek Supreme Universal Restorative) bonded with either 3M ESPE Single Bond or Clearfil SE Bond following manufacturers' instructions. Specimens were stressed in shear at 1 mm/min to failure (microshear bond strength). Etched enamel surfaces and enamel-adhesive interfaces were examined under scanning electron microscopy. The microshear bond strength (MPa) of resin composite bonded to hypomineralized enamel was significantly lower than for control enamel (3M ESPE Single Bond=7.08 +/- 4.90 vs 16.27 +/- 10.04; Clearfil SE Bond=10.39 +/- 7.56 vs 19.63 +/- 7.42; P=.001). Fractures were predominantly adhesive in control enamel and cohesive in hypomineralized enamel. Scotchbond etchant produced deep interprismatic and intercrystal porosity in control enamel and shallow etch patterns with minimal intercrystal porosity in hypomineralized enamel. Control enamel appeared almost unaffected by SE Primer; hypomineralized enamel showed shallow etching. The hypomineralized enamel-adhesive interface was porous with cracks in the enamel. The control enamel-adhesive interface displayed a hybrid layer of even thickness. The microshear bond strength of resin composite bonded to hypomineralized enamel was significantly lower than for control enamel. This was supported by differences seen in etch patterns and at the enamel-adhesive interface.

  6. A valence bond study of three-center four-electron pi bonding: electronegativity vs electroneutrality.

    PubMed

    DeBlase, Andrew; Licata, Megan; Galbraith, John Morrison

    2008-12-18

    Three-center four-electron (3c4e) pi bonding systems analogous to that of the ozone molecule have been studied using modern valence bond theory. Molecules studied herein consist of combinations of first row atoms C, N, and O with the addition of H atoms where appropriate in order to preserve the 3c4e pi system. Breathing orbital valence bond (BOVB) calculations were preformed at the B3LYP/6-31G**-optimized geometries in order to determine structural weights, pi charge distributions, resonance energies, and pi bond energies. It is found that the most weighted VB structure depends on atomic electronegativity and charge distribution, with electronegativity as the dominant factor. By nature, these systems are delocalized, and therefore, resonance energy is the main contributor to pi bond energies. Molecules with a single dominant VB structure have low resonance energies and therefore low pi bond energies.

  7. Backbone conformation affects duplex initiation and duplex propagation in hybridisation of synthetic H-bonding oligomers.

    PubMed

    Iadevaia, Giulia; Núñez-Villanueva, Diego; Stross, Alexander E; Hunter, Christopher A

    2018-06-06

    Synthetic oligomers equipped with complementary H-bond donor and acceptor side chains form multiply H-bonded duplexes in organic solvents. Comparison of the duplex forming properties of four families of oligomers with different backbones shows that formation of an extended duplex with three or four inter-strand H-bonds is more challenging than formation of complexes that make only two H-bonds. The stabilities of 1 : 1 complexes formed between length complementary homo-oligomers equipped with either phosphine oxide or phenol recognition modules were measured in toluene. When the backbone is very flexible (pentane-1,5-diyl thioether), the stability increases uniformly by an order of magnitude for each additional base-pair added to the duplex: the effective molarities for formation of the first intramolecular H-bond (duplex initiation) and subsequent intramolecular H-bonds (duplex propagation) are similar. This flexible system is compared with three more rigid backbones that are isomeric combinations of an aromatic ring and methylene groups. One of the rigid systems behaves in exactly the same way as the flexible backbone, but the other two do not. For these systems, the effective molarity for formation of the first intramolecular H-bond is the same as that found for the other two backbones, but additional H-bonds are not formed between the longer oligomers. The effective molarities are too low for duplex propagation in these systems, because the oligomer backbones cannot adopt conformations compatible with formation of an extended duplex.

  8. Fracture surface analysis in composite and titanium bonding

    NASA Technical Reports Server (NTRS)

    Devilbiss, T. A.; Wightman, J. P.

    1985-01-01

    To understand the mechanical properties of fiber-reinforced composite materials, it is necessary to understand the mechanical properties of the matrix materials and of the reinforcing fibers. Another factor that can affect the mechanical properties of a composite material is the interaction between the fiber and the matrix. In general, composites with strong fiber matrix bonding will give higher modulus, lower toughness composites. Composites with weak bonding will have a lower modulus and more ductility. The situation becomes a bit more complex when all possibilities are examined. To be considered are the following: the properties of the surface layer on the fiber, the interactive forces between polymer and matrix, the surface roughness and porosity of the fiber, and the morphology of the matrix polymer at the fiber surface. In practice, the surface of the fibers is treated to enhance the mechanical properties of a composite. These treatments include anodization, acid etching, high temperature oxidation, and plasma oxidation, to name a few. The goal is to be able to predict the surface properties of carbon fibers treated in various ways, and then to relate surface properties to fiber matrix bonding.

  9. Essential Factors Influencing the Bonding Strength of Cold-Sprayed Aluminum Coatings on Ceramic Substrates

    NASA Astrophysics Data System (ADS)

    Drehmann, R.; Grund, T.; Lampke, T.; Wielage, B.; Wüstefeld, C.; Motylenko, M.; Rafaja, D.

    2018-02-01

    The present work summarizes the most important results of a research project dealing with the comprehensive investigation of the bonding mechanisms between cold-sprayed Al coatings and various poly- and monocrystalline ceramic substrates (Al2O3, AlN, Si3N4, SiC, MgF2). Due to their exceptional combination of properties, metallized ceramics are gaining more and more importance for a wide variety of applications, especially in electronic engineering. Cold spray provides a quick, flexible, and cost-effective one-step process to apply metallic coatings on ceramic surfaces. However, since most of the existing cold-spray-related publications focus on metallic substrates, only very little is known about the bonding mechanisms acting between cold-sprayed metals and ceramic substrates. In this paper, the essential factors influencing the bonding strength in such composites are identified. Besides mechanical tensile strength testing, a thorough analysis of the coatings and especially the metal/ceramic interfaces was conducted by means of HRTEM, FFT, STEM, EDX, EELS, GAXRD, and EBSD. The influence of substrate material, substrate temperature, and particle size is evaluated. The results suggest that, apart from mechanical interlocking, the adhesion of cold-sprayed metallic coatings on ceramics is based on a complex interplay of different mechanisms such as quasiadiabatic shearing, static recrystallization, and heteroepitaxial growth.

  10. Social Bonds, Early Trauma and Smoking: Evidence of the Group Specific Relevance of Control Theory.

    ERIC Educational Resources Information Center

    Pawlak, Rebecca; DeFronzo, James

    1993-01-01

    Analyzed data from 595 adults to evaluate potential effects of social bonds and childhood trauma on tobacco smoking. Although both control factors and childhood experiences affected smoking, religious belief and belief in importance of conforming to moral and social norms had more important and robust negative relationships to smoking than…

  11. Curing mode affects bond strength of adhesively luted composite CAD/CAM restorations to dentin.

    PubMed

    Lührs, Anne-Katrin; Pongprueksa, Pong; De Munck, Jan; Geurtsen, Werner; Van Meerbeek, Bart

    2014-03-01

    To determine the effect of curing mode and restoration-surface pre-treatment on the micro-tensile bond strength (μTBS) to dentin. Sandblasted CAD/CAM composite blocks (LAVA Ultimate, 3M ESPE) were cemented to bur-cut dentin using either the etch & rinse composite cement Nexus 3 ('NX3', Kerr) with Optibond XTR ('XTR', Kerr), or the self-etch composite cement RelyX Ultimate ('RXU', 3M ESPE) with Scotchbond Universal ('SBU', 3M ESPE). All experimental groups included different 'curing modes' (light-curing of adhesive and cement ('LL'), light-curing of adhesive and auto-cure of cement ('LA'), co-cure of adhesive through light-curing of cement ('AL'), or complete auto-cure ('AA')) and different 'restoration-surface pre-treatments' of the composite block (NX3: either a silane primer (Kerr), or the XTR adhesive; RXU: either silane primer (RelyX Ceramic Primer, 3M ESPE) and SBU, or solely SBU). After water-storage (7 days, 37°C), the μTBS was measured. Additionally, the degree of conversion (DC) of both cements was measured after 10min and after 1 week, either auto-cured (21°C/37°C) or light-cured (directly/through 3-mm CAD/CAM composite). The linear mixed-effects model (α=0.05) revealed a significant influence of the factors 'curing mode' and 'composite cement', and a less significant effect of the factor 'restoration-surface pre-treatment'. Light-curing 'LL' revealed the highest μTBS, which decreased significantly for all other curing modes. For curing modes 'AA' and 'AL', the lowest μTBS and a high percentage of pre-testing failures were reported. Overall, DC increased with light-curing and incubation time. The curing mode is decisive for the bonding effectiveness of adhesively luted composite CAD/CAM restorations to dentin. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  12. Verification of surface preparation for adhesive bonding

    NASA Technical Reports Server (NTRS)

    Myers, Rodney S.

    1995-01-01

    A survey of solid rocket booster (SRB) production operations identified potential contaminants which might adversely affect bonding operations. Lap shear tests quantified these contaminants' effects on adhesive strength. The most potent contaminants were selected for additional studies on SRB thermal protection system (TPS) bonding processes. Test panels were prepared with predetermined levels of contamination, visually inspected using white and black light, then bonded with three different TPS materials over the unremoved contamination. Bond test data showed that white and black light inspections are adequate inspection methods for TPS bonding operations. Extreme levels of contamination (higher than expected on flight hardware) had an insignificant effect on TPS bond strengths because of the apparent insensitivity of the adhesive system to contamination effects, and the comparatively weak cohesive strength of the TPS materials.

  13. Resin-dentin bonds to EDTA-treated vs. acid-etched dentin using ethanol wet-bonding. Part II: Effects of mechanical cycling load on microtensile bond strengths.

    PubMed

    Sauro, Salvatore; Toledano, Manuel; Aguilera, Fatima Sánchez; Mannocci, Francesco; Pashley, David H; Tay, Franklin R; Watson, Timothy F; Osorio, Raquel

    2011-06-01

    To compare microtensile bond strengths (MTBS) subsequent to load cycling of resin bonded acid-etched or EDTA-treated dentin using a modified ethanol wet-bonding technique. Flat dentin surfaces were obtained from extracted human molars and conditioned using 37% H(3)PO(4) (PA) (15s) or 0.1M EDTA (60s). Five experimental adhesives and one commercial bonding agent were applied to the dentin and light-cured. Solvated experimental resins (50% ethanol/50% comonomers) were used as primers and their respective neat resins were used as the adhesives. The resin-bonded teeth were stored in distilled water (24h) or submitted to 5000 loading cycles of 90N. The bonded teeth were then sectioned in beams for MTBS. Modes of failure were examined by scanning electron microscopy. The most hydrophobic resin 1 gave the lowest bond strength values to both acid and EDTA-treated dentin. The hydrophobic resin 2 applied to EDTA-treated dentin showed lower bond strengths after cycling load but this did not occur when it was bonded to PA-etched dentin. Resins 3 and 4, which contained hydrophilic monomers, gave higher bond strengths to both EDTA-treated or acid-etched dentin and showed no significant difference after load cycling. The most hydrophilic resin 5 showed no significant difference in bond strengths after cycling loading when bonded to EDTA or phosphoric acid treated dentin but exhibited low bond strengths. The presence of different functional monomers influences the MTBS of the adhesive systems when submitted to cyclic loads. Adhesives containing hydrophilic comonomers are not affected by cycling load challenge especially when applied on EDTA-treated dentin followed by ethanol wet bonding. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  14. Empirical evidence for an invariant three-factor structure of the Parental Bonding Instrument in six European countries.

    PubMed

    Heider, Dirk; Matschinger, Herbert; Bernert, Sebastian; Vilagut, Gemma; Martínez-Alonso, Montserrat; Dietrich, Sandra; Angermeyer, Matthias C

    2005-06-30

    The objective of the present study was to test the Parental Bonding Instrument's (PBI) three-factor structure (care, overprotection, and authoritarianism) found by [Cox, B.J., Enns, M.W., Clara, I.P. 2000, The Parental Bonding Instrument: confirmatory evidence for a three-factor model in a psychiatric clinical sample and in the National Comorbidity Survey, Social Psychiatry and Psychiatric Epidemiology 35 (2000) 353-357.] on an eight-item short form of the scale. A total of 8813 respondents from the six European countries participating in the ESEMeD project (Belgium, France, Germany, Italy, The Netherlands, and Spain) completed either the PBI-paternal or the PBI-maternal scale. Maximum likelihood confirmatory factor analysis was used to compare the original factor model of Cox et al. with a three-factor solution that emerged from an exploration of the structure with principal component factor analysis. When gender and age subgroups, as well as different countries, were taken into account, the accuracy of the model was confirmed. The fit indices for the new model indicated a generally better model fit than the ones for the model originally developed by Cox et al. Further efforts should be directed to the modeling of the dimension authoritarianism. The results provide the opportunity to estimate the influence of the extracted factors on mental disorders in different countries. The application of the short form of the PBI seems suitable primarily for large epidemiological studies.

  15. Economic and Cultural Factors Affecting University Excellence

    ERIC Educational Resources Information Center

    Jabnoun, Naceur

    2009-01-01

    Purpose: The ranking of top universities in the world has generated increased interest in the factors that enhance university performance. The purpose of this paper is to identify economic and cultural factors that affect the number of top ranking universities in each country. Design/methodology/approach: This paper first identifies the number of…

  16. Lack of Breastfeeding: A Potential Risk Factor in the Multifactorial Genesis of Borderline Personality Disorder and Impaired Maternal Bonding.

    PubMed

    Schwarze, Cornelia E; Hellhammer, Dirk H; Stroehle, Verena; Lieb, Klaus; Mobascher, Arian

    2015-10-01

    Borderline personality disorder (BPD) is characterized by a pattern of intense but unstable interpersonal relationships. These interpersonal dysfunctions may originate from impaired bonding and attachment that is determined during early life. Remarkably, it has been reported that the quality of mother-infant relationship is influenced by the feeding mode. Thus, bottle feeding instead of breastfeeding and possible lack of maternal bonding-related behavior may increase the risk for later psychopathology and attachment problems as seen in BPD. A total of 100 BPD patients and 100 matched healthy controls underwent semistructured interviews, based on retrospective information about early risk factors and breastfeeding during infancy. The authors' analyses revealed that BPD patients were significantly less breastfed compared to healthy controls (no breastfeeding in BPD: 42.4%; no breastfeeding in controls: 18.2%; p < .001). The BPD diagnosis was significantly predicted by the variable "no breastfeeding" (p < .001; odds ratio [OR] = 3.32; confidence interval [CI] [1.74, 6.34]), even after adjustment for childhood trauma and several confounding factors (p = .001). The variable "no breastfeeding" accounts for 9.1% of the variance of the BPD diagnosis and is associated with low perceived maternal bonding (p = .006). Breastfeeding may act as an early indicator of the mother-infant relationship that seems to be relevant for bonding and attachment later in life.

  17. ENVIRONMENTAL FACTORS AFFECTING BREAST CANCER SUSCEPTIBILITY

    EPA Science Inventory

    Environmental Factors Affecting Breast Cancer Susceptibility
    Suzanne. E. Fenton
    US EPA, ORD, MD-67 NHEERL, Reproductive Toxicology Division, Research Triangle Park, NC 27711.

    Breast cancer is still the most common malignancy afflicting women in the Western world. Alt...

  18. Factors Affecting Radon Concentration in Houses

    NASA Astrophysics Data System (ADS)

    Al-Sharif, Abdel-Latif; Abdelrahman, Y. S.

    2001-03-01

    The dangers to the human health upon exposure to radon and its daughter products is the main motivation behind the vast number of studies performed to find the concentration of radon in our living environment, including our houses. The presence of radon and its daughter products in houses are due to various sources including building materials and the soil under the houses. Many factors affect radon concentration in our houses, the elevation above ground level,ventilation, building materials and room usage being among these factors. In our paper, we discuss the effect of elevation above ground level, room usage and ventilation on the Radon concentration in houses. The faculty residences of the Mu'tah University (Jordan) were chosen in our study. Our results showed that the concentration of radon decreases with elevation. Ventilation rate was also found to affect radon concentration, where low concentrations observed for areas with good ventilation.

  19. Students' Perceptions of Parental Bonding Styles and Their Academic Burnout

    ERIC Educational Resources Information Center

    Shin, Hyojung; Lee, Jayoung; Kim, Boyoung; Lee, Sang Min

    2012-01-01

    This study investigated how parental bonding style affects academic burnout in Korean adolescents. Participants were 447 middle school students, who completed the Parental Bonding Instrument and the Maslach Burnout Inventory-Student Survey. MANCOVA results confirmed that adolescents reporting the optimal bonding parental style, for both mother and…

  20. Factors affecting caregivers' ability to make environmental modifications.

    PubMed

    Messecar, D C

    2000-12-01

    This study explored factors that family caregivers described as affecting their ability to use environmental modifications. Intensive interviews and participant observation were used to collect detailed data from 24 primary family caregivers. Several factors that affect the caregivers' ability to implement modification strategies were identified in the analysis. These factors included attributes of the elderly individual, attributes of the modification, quality of the caregiver-elderly relationship, caregivers' skills, personal resources of the caregiver, and the informal and formal supports available. Of these factors, the most important were the salient skills that caregivers need to implement environmental modifications. These findings point to the importance of caregivers receiving skills training in this important dimension of caregiving. Intervention should be based on a collaborative approach that ensures the caregiver and care receiver's needs and preferences are respected.

  1. Effects of tacky mat contamination on bond degradation for Chemlok/liner and NBR/liner bonds

    NASA Technical Reports Server (NTRS)

    Padilla, A. M.

    1989-01-01

    Tacky mats are placed by the rubber lay-up areas for the solid rocket motor segments. These mats dust off the shoes prior to entering the platform where the lay-up work is performed. The possibility exists that a tacky mat could be touched with gloved hands prior to handling the uncured nitride butadiene rubber (NBR). Tests were run to determine if NBR were accidentally touched would there be any degradation of the liner/NBR bond. The tacky mats were judged solely on the basis of bond degradation caused by either direct or indirect contamination. Test results all indicate that there was no notable NBR/Chemlok or liner/NBR bond degradation on samples that came into contact with the tacky mat material. Testing procedures are described. The tacky mat adhesive composition does not contain fluorocarbons or release agents that would affect bonding.

  2. Oxytocin and Social Bonds: The Role of Oxytocin in Perceptions of Romantic Partners’ Bonding Behavior

    PubMed Central

    Algoe, Sara B.; Kurtz, Laura E.; Grewen, Karen

    2017-01-01

    In this research, we tested hypotheses about the role of oxytocin in adult human bonding. Inspired by revisiting the research on pair bonding in microtine voles that fueled psychologists’ interest in the role of oxytocin in social life, we drew on recent theory from affective and relationship science to identify a well-defined bonding context for human romantic relationships. We then paired these behaviors and subjective psychological responses with a measure of naturally circulating oxytocin. In 129 romantically involved adults whose partner expressed gratitude to them in the lab, greater oxytocin over the prior 24 hr was associated with greater perceptions of the expresser’s responsiveness and gratitude, as well as greater experienced love, but not general affective reward. Moreover, in this one-time conversation, higher oxytocin acted like rose-colored glasses, attenuating the effect of a partner’s behaviorally coded expressive behavior on perceptions of the expresser’s responsiveness. These results justify future research on the role of oxytocin in psychological aspects of growth processes. PMID:28968183

  3. Effect of Er,Cr:YSGG laser on the microtensile bond strength of two different adhesives to the sound and caries-affected dentin.

    PubMed

    Ergücü, Z; Celik, E U; Unlü, N; Türkün, M; Ozer, F

    2009-01-01

    This study examined the effect of Er,Cr:YSGG laser irradiation on the microtensile bond strength (microTBS) of a three-step etch-and-rinse and a two-step self-etch adhesive to sound and caries-affected dentin. Sixteen freshly extracted human molars with occlusal dentin caries were used. The caries lesion was removed by one of the following methods: conventional treatment with burs or Er,Cr:YSGG laser (Waterlase MD, Biolase). The adhesive systems (AdheSE, Ivoclar Vivadent and Scotchbond Multi Purpose, 3M ESPE) were applied to the entire tooth surface according to the manufacturers' instructions. Resin composites were applied to the adhesive-treated dentin surfaces and light-cured. Each tooth was sectioned into multiple beams with the "non-trimming" version of the microtensile test. The specimens were subjected to microtensile forces (BISCO Microtensile Tester, BISCO). The data was analyzed by three-way ANOVA and independent t-tests (p=0.05). Er,Cr:YSGG laser irradiation exhibited similar microTBS values compared to that of conventional bur treatment, regardless of the adhesive system and type of treated dentin. The self-etch system revealed lower microTBS values, both with conventional and laser treatment techniques, compared to the etch-and-rinse adhesive in sound and caries-affected dentin (p<0.05). Er,Cr:YSGG laser irradiation did not negatively affect the bonding performance of adhesive systems to sound and caries-affected dentin.

  4. A modified low-temperature wafer bonding method using spot pressing bonding technique and water glass adhesive layer

    NASA Astrophysics Data System (ADS)

    Xu, Yang; Wang, Shengkai; Wang, Yinghui; Chen, Dapeng

    2018-02-01

    A modified low-temperature wafer bonding method using a spot pressing bonding technique and a water glass adhesive layer is proposed. The electrical properties of the water glass layer has been studied by capacitance-voltage (C-V) and electric current-voltage (I-V) measurements. It is found that the adhesive layer can be regarded as a good insulator in terms of leakage current density. The bonding mechanism and the motion of bubbles during the thermal treatment are investigated. The dominant factor for the bubble motion in the modified bonding process is the gradient of pressure introduced by the spot pressing force. It is proved that the modified method achieves low-temperature adhesive bonding, minimizes the effect of water desorption, and provides good bonding performance.

  5. Fiber post cementation strategies: effect of mechanical cycling on push-out bond strength and cement polymerization stress.

    PubMed

    Bergoli, Cesar Dalmolin; Amaral, Marina; Boaro, Leticia Cristina; Braga, Roberto Ruggiero; Valandro, Luiz Felipe

    2012-08-01

    To evaluate the effect of mechanical cycling and cementation strategies on the push-out bond strength between fiber posts and root dentin and the polymerization stresses produced using three resin cements. Eighty bovine mandibular teeth were sectioned to a length of 16 mm, prepared to 12 mm, and embedded in self-curing acrylic resin. The specimens were then distributed into 8 groups (n = 10): Gr1 - Scotchbond Multi Purpose + RelyX ARC; Gr2 - Scotchbond Multi Purpose + RelyX ARC + mechanical cycling; Gr3 - AdheSE + Multilink Automix; Gr4 - AdheSE + Multilink Automix + mechanical cycling; Gr5 - phosphoric acid + RelyX U100 (self-adhesive cement); Gr6 - phosphoric acid+ RelyX U100 + mechanical cycling; Gr7 - RelyX U100; Gr8 - RelyX U100 + mechanical cycling. The values obtained from the push-out bond strength test were submitted to two-way ANOVA and Tukey's test (p = 0.05), while the values obtained from the polymerization stress test were subjected to one-way ANOVA and Tukey's test (α = 0.05). Mechanical cycling did not affect the bond strength values (p = 0.236), while cementation strategies affected the push-out bond strength (p < 0.001). Luting with RelyX U100 and Scotch Bond Multi Purpose + RelyX ARC yielded higher push-out bond strength values. The polymerization stress results were affected by the factor "cement" (p = 0.0104): the self-adhesive cement RelyX U100 exhibited the lowest values, RelyX ARC resulted in the highest values, while Multilink Automix presented values statistically similar to the other two cements. The self-adhesive cement appears to be a good alternative for luting fiber posts due to the high push-out bond strengths and lower polymerization stress values.

  6. Which factors affect software projects maintenance cost more?

    PubMed

    Dehaghani, Sayed Mehdi Hejazi; Hajrahimi, Nafiseh

    2013-03-01

    The software industry has had significant progress in recent years. The entire life of software includes two phases: production and maintenance. Software maintenance cost is increasingly growing and estimates showed that about 90% of software life cost is related to its maintenance phase. Extraction and considering the factors affecting the software maintenance cost help to estimate the cost and reduce it by controlling the factors. In this study, the factors affecting software maintenance cost were determined then were ranked based on their priority and after that effective ways to reduce the maintenance costs were presented. This paper is a research study. 15 software related to health care centers information systems in Isfahan University of Medical Sciences and hospitals function were studied in the years 2010 to 2011. Among Medical software maintenance team members, 40 were selected as sample. After interviews with experts in this field, factors affecting maintenance cost were determined. In order to prioritize the factors derived by AHP, at first, measurement criteria (factors found) were appointed by members of the maintenance team and eventually were prioritized with the help of EC software. Based on the results of this study, 32 factors were obtained which were classified in six groups. "Project" was ranked the most effective feature in maintenance cost with the highest priority. By taking into account some major elements like careful feasibility of IT projects, full documentation and accompany the designers in the maintenance phase good results can be achieved to reduce maintenance costs and increase longevity of the software.

  7. Matrix isolation technique for the study of some factors affecting the partitioning of trace elements. [using vibrational spectroscopy

    NASA Technical Reports Server (NTRS)

    Grzybowski, J. M.; Allen, R. O.

    1974-01-01

    The factors that affect the preferred positions of cations in ionic solid solutions were investigated utilizing vibrational spectroscopy. Solid solutions of the sulfate and chromate ions codoped with La(+3) and Ca(+2) in a KBr host lattice were examined as a function of the polyvalent cation concentration. The cation-anion pairing process was found to be random for Ca(+2), whereas the formation of La(+3)-SO4(-2) ion pairs with a C2 sub v bonding geometry is highly preferential to any type of La(+3)-CrO4(-2) ion pair formation. The relative populations of ion pair site configurations are discussed in terms of an energy-entropy competition model which can be applied to the partition of trace elements during magmatic processes.

  8. Orthodontic bracket bonding without previous adhesive priming: A meta-regression analysis.

    PubMed

    Altmann, Aline Segatto Pires; Degrazia, Felipe Weidenbach; Celeste, Roger Keller; Leitune, Vicente Castelo Branco; Samuel, Susana Maria Werner; Collares, Fabrício Mezzomo

    2016-05-01

    To determine the consensus among studies that adhesive resin application improves the bond strength of orthodontic brackets and the association of methodological variables on the influence of bond strength outcome. In vitro studies were selected to answer whether adhesive resin application increases the immediate shear bond strength of metal orthodontic brackets bonded with a photo-cured orthodontic adhesive. Studies included were those comparing a group having adhesive resin to a group without adhesive resin with the primary outcome measurement shear bond strength in MPa. A systematic electronic search was performed in PubMed and Scopus databases. Nine studies were included in the analysis. Based on the pooled data and due to a high heterogeneity among studies (I(2)  =  93.3), a meta-regression analysis was conducted. The analysis demonstrated that five experimental conditions explained 86.1% of heterogeneity and four of them had significantly affected in vitro shear bond testing. The shear bond strength of metal brackets was not significantly affected when bonded with adhesive resin, when compared to those without adhesive resin. The adhesive resin application can be set aside during metal bracket bonding to enamel regardless of the type of orthodontic adhesive used.

  9. Preslaughter factors affecting poultry meat quality chapter 2.

    USDA-ARS?s Scientific Manuscript database

    Poultry meat quality is affected by numerous antemortem factors, in particular those occurring during the last 24 hours that the bird is alive. These short term factors influence carcass yield (live shrink), carcass defects (bruising, broken/dislocated bones), carcass microbiological contamination, ...

  10. FACTORS ADVERSELY AFFECTING AMPHIBIAN POPULATIONS IN THE US

    EPA Science Inventory

    Factors known or suspected to be adversely affecting native amphibian populations in the US were identified using information from species accounts written in a standardized format by multiple authors in a forthcoming book. Specific adverse factors were identified for 53 (58%) of...

  11. Factors affecting radiographers' organizational commitment.

    PubMed

    Akroyd, Duane; Jackowski, Melissa B; Legg, Jeffrey S

    2007-01-01

    A variety of factors influence employees' attitudes toward their workplace and commitment to the organization that employs them. However, these factors have not been well documented among radiologic technologists. To determine the predictive ability of selected organizational, leadership, work-role and demographic variables on organizational commitment for a national sample of radiographers. Three thousand radiographers registered by the American Registry of Radiologic Technologists working full time in clinical settings were surveyed by mail regarding their commitment to their employers, leadership within the organization that employs them, employer support and demographic information. Overall, radiographers were found to have only a moderate level of commitment to their employers. Among the factors that significantly affected commitment were the radiographer's educational level, perceived level of organizational support, role clarity and organizational leadership. The results of this study could provide managers and supervisors with insights on how to empower and challenge radiographers and offer opportunities that will enhance radiographers' commitment to the organization, thus reducing costly turnover and improving employee performance.

  12. 1 mil gold bond wire study.

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

    Huff, Johnathon; McLean, Michael B.; Jenkins, Mark W.

    2013-05-01

    In microcircuit fabrication, the diameter and length of a bond wire have been shown to both affect the current versus fusing time ratio of a bond wire as well as the gap length of the fused wire. This study investigated the impact of current level on the time-to-open and gap length of 1 mil by 60 mil gold bond wires. During the experiments, constant current was provided for a control set of bond wires for 250ms, 410ms and until the wire fused; non-destructively pull-tested wires for 250ms; and notched wires. The key findings were that as the current increases, themore » gap length increases and 73% of the bond wires will fuse at 1.8A, and 100% of the wires fuse at 1.9A within 60ms. Due to the limited scope of experiments and limited data analyzed, further investigation is encouraged to confirm these observations.« less

  13. School Delinquency and Social Bond Factors: Exploring Gendered Differences among a National Sample of 10th Graders

    ERIC Educational Resources Information Center

    Hart, Caroline O.; Mueller, Christian E.

    2013-01-01

    School delinquency has been linked to an array of negative educational outcomes, and if left unchecked, may lead to more serious problems in adulthood. Identifying the risk and protective factors that influence school delinquency is therefore crucial to develop effective intervention programs. Utilizing Hirschi's social bond theory as a framework,…

  14. Estimation of Hydrogen-Exchange Protection Factors from MD Simulation Based on Amide Hydrogen Bonding Analysis

    PubMed Central

    Park, In-Hee; Venable, John D.; Steckler, Caitlin; Cellitti, Susan E.; Lesley, Scott A.; Spraggon, Glen; Brock, Ansgar

    2015-01-01

    Hydrogen exchange (HX) studies have provided critical insight into our understanding of protein folding, structure and dynamics. More recently, Hydrogen Exchange Mass Spectrometry (HX-MS) has become a widely applicable tool for HX studies. The interpretation of the wealth of data generated by HX-MS experiments as well as other HX methods would greatly benefit from the availability of exchange predictions derived from structures or models for comparison with experiment. Most reported computational HX modeling studies have employed solvent-accessible-surface-area based metrics in attempts to interpret HX data on the basis of structures or models. In this study, a computational HX-MS prediction method based on classification of the amide hydrogen bonding modes mimicking the local unfolding model is demonstrated. Analysis of the NH bonding configurations from Molecular Dynamics (MD) simulation snapshots is used to determine partitioning over bonded and non-bonded NH states and is directly mapped into a protection factor (PF) using a logistics growth function. Predicted PFs are then used for calculating deuteration values of peptides and compared with experimental data. Hydrogen exchange MS data for Fatty acid synthase thioesterase (FAS-TE) collected for a range of pHs and temperatures was used for detailed evaluation of the approach. High correlation between prediction and experiment for observable fragment peptides is observed in the FAS-TE and additional benchmarking systems that included various apo/holo proteins for which literature data were available. In addition, it is shown that HX modeling can improve experimental resolution through decomposition of in-exchange curves into rate classes, which correlate with prediction from MD. Successful rate class decompositions provide further evidence that the presented approach captures the underlying physical processes correctly at the single residue level. This assessment is further strengthened in a comparison of

  15. Factors Affecting Faculty Web Portal Usability

    ERIC Educational Resources Information Center

    Bringula, Rex P.; Basa, Roselle S.

    2011-01-01

    The study investigated the factors that might significantly affect web portal usability. Results of the study were intended to serve as inputs for faculty web portal development of the University of the East-Manila. Descriptive statistics utilized questionnaire data from 82 faculty members. The data showed that most of the respondents were…

  16. Low Calorie Diet Affects Aging-Related Factors

    MedlinePlus

    ... Research News From NIH Low Calorie Diet Affects Aging-Related Factors Past Issues / Summer 2006 Table of ... project sponsored by the NIH's National Institute on Aging (NIA) to learn more about the effects of ...

  17. What Factors Affect Response to Ads? A Perspective.

    ERIC Educational Resources Information Center

    Rotzoll, Kim B.

    The concept of "frame of reference" offers a perspective from which to examine the many factors which affect advertising response. The advertiser is interested in affecting two types of overt behavior. First, the individual is induced to select a particular stimulus (the advertisement) from competing stimuli (such as other people, noise,…

  18. Erosive cola-based drinks affect the bonding to enamel surface: an in vitro study.

    PubMed

    Casas-Apayco, Leslie Caroll; Dreibi, Vanessa Manzini; Hipólito, Ana Carolina; Graeff, Márcia Sirlene Zardin; Rios, Daniela; Magalhães, Ana Carolina; Buzalaf, Marília Afonso Rabelo; Wang, Linda

    2014-01-01

    This study aimed to assess the impact of in vitro erosion provoked by different cola-based drinks (Coke types), associated or not with toothbrushing, to bonding to enamel. Fifty-six [Corrected] bovine enamel specimens were prepared and randomly assigned into seven groups (N=8): C- Control (neither eroded nor abraded), ERO-RC: 3x/1-minute immersion in Regular Coke (RC), ERO-LC: 3x/1-minute immersion in Light Coke (LC), ERO-ZC: 3x/1-minute immersion in Zero Coke (ZC) and three other eroded groups, subsequently abraded for 1-minute toothbrushing (EROAB-RC, EROAB-LC and EROAB-ZC, respectively). After challenges, they were stored overnight in artificial saliva for a total of 24 hours and restored with Adper Single Bond 2/Filtek Z350. Buildup coronal surfaces were cut in 1 mm2 -specimens and subjected to a microtensile test. Data were statistically analyzed by two-way ANOVA/Bonferroni tests (α=0.05). Failure modes were assessed by optical microscopy (X40). The Interface of the restorations were observed using Confocal Laser Scanning Microscopy (CLSM). All tested cola-based drinks significantly reduced the bond strength, which was also observed in the analyses of interfaces. Toothbrushing did not have any impact on the bond strength. CLSM showed that except for Zero Coke, all eroded specimens resulted in irregular hybrid layer formation. All cola-based drinks reduced the bond strength. Different patterns of hybrid layers were obtained revealing their impact, except for ZC.

  19. Resin–dentin bonds to EDTA-treated vs. acid-etched dentin using ethanol wet-bonding

    PubMed Central

    Sauro, Salvatore; Toledano, Manuel; Aguilera, Fatima Sánchez; Mannocci, Francesco; Pashley, David H.; Tay, Franklin R.; Watson, Timothy F.; Osorio, Raquel

    2013-01-01

    Objective To compare resin–dentin bond strengths and the micropermeability of hydrophobic vs. hydrophilic resins bonded to acid-etched or EDTA-treated dentin, using the ethanol wet-bonding technique. Methods Flat dentin surfaces from extracted human third molars were conditioned before bonding with: 37% H3PO4 (15 s) or 0.1 M EDTA (60 s). Five experimental resin blends of different hydrophilicities and one commercial adhesive (SBMP: Scotchbond Multi-Purpose) were applied to ethanol wet-dentin (1 min) and light-cured (20 s). The solvated resins were used as primers (50% ethanol/50% comonomers) and their respective neat resins were used as the adhesive. The resin-bonded teeth were stored in distilled water (24 h) and sectioned in beams for microtensile bond strength testing. Modes of failure were examined by stereoscopic light microscopy and SEM. Confocal tandem scanning microscopy (TSM) interfacial characterization and micropermeability were also performed after filling the pulp chamber with 1 wt% aqueous rhodamine-B. Results The most hydrophobic resin 1 gave the lowest bond strength values to acid-etched dentin and all beams failed prematurely when the resin was applied to EDTA-treated dentin. Resins 2 and 3 gave intermediate bond strengths to both conditioned substrates. Resin 4, an acidic hydrophilic resin, gave the highest bond strengths to both EDTA-treated and acid-etched dentin. Resin 5 was the only hydrophilic resin showing poor resin infiltration when applied on acid-etched dentin. Significance The ethanol wet-bonding technique may improve the infiltration of most of the adhesives used in this study into dentin, especially when applied to EDTA-treated dentin. The chemical composition of the resin blends was a determining factor influencing the ability of adhesives to bond to EDTA-treated or 37% H3PO4 acid-etched dentin, when using the ethanol wet-bonding technique in a clinically relevant time period. PMID:20074787

  20. Affective and Social Factors in a Project-Based Writing Course

    ERIC Educational Resources Information Center

    Kathpalia, Sujata Surinder; Heah, Carmel

    2011-01-01

    Much of the work in academic writing has focused on the cognitive rather than the affective and social aspects involved in project-based writing. Emphasis in past research has been on skills and processes of writing rather than on affective factors such as motivation, attitudes, feelings or social factors involving intrapersonal and interpersonal…

  1. Substrate-Related Factors Affecting Enzymatic Saccharification of Lignocelluloses: Our Recent Understanding

    Treesearch

    Shao-Yuan Leu; J.Y. Zhu

    2013-01-01

    Enzymatic saccharification of cellulose is a key step in conversion of plant biomass to advanced biofuel and chemicals. Many substrate-related factors affect saccharification. Rather than examining the role of each individual factor on overall saccharification efficiency, this study examined how each factor affects the three basic processes of a heterogeneous...

  2. Microbiologic factors affecting Clostridium difficile recurrence.

    PubMed

    Chilton, C H; Pickering, D S; Freeman, J

    2018-05-01

    Recurrent Clostridium difficile infection (rCDI) places a huge economic and practical burden on healthcare facilities. Furthermore, rCDI may affect quality of life, leaving patients in an rCDI cycle and dependant on antibiotic therapy. To discuss the importance of microbiologic factors in the development of rCDI. Literature was drawn from a search of PubMed from 2000 onwards with the search term 'recurrent Clostridium difficile infection' and further references cited within these articles. Meta-analyses and systematic reviews have shown that CDI and rCDI risk factors are similar. Development of rCDI is attendant on many factors, including immune status or function, comorbidities and concomitant treatments. Studies suggest that poor bacterial diversity is correlated with clinical rCDI. Narrow-spectrum gut microflora-sparing antimicrobials (e.g. surotomycin, cadazolid, ridinilazole) are in development for CDI treatment, while microbiota therapeutics (faecal microbiota transplantation, nontoxigenic C. difficile, stool substitutes) are increasingly being explored. rCDI can only occur when viable C. difficile spores are present, either within the gut lumen after infection or when reacquired from the environment. C. difficile spore germination can be influenced by gut environmental factors resulting from dysbiosis, and spore outgrowth may be affected stage by some antimicrobials (e.g. fidaxomicin, ramoplanin, oritavancin). rCDI is a significant challenge for healthcare professionals, requiring a multifaceted approach; optimized infection control to minimize reinfection; C. difficile-targeted antibiotics to minimize dysbiosis; and gut microflora restoration to promote colonization resistance. These elements should be informed by our understanding of the microbiologic factors involved in both C. difficile itself and the gut microbiome. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  3. Sibling bereavement and continuing bonds.

    PubMed

    Packman, Wendy; Horsley, Heidi; Davies, Betty; Kramer, Robin

    2006-11-01

    Historically, from a Freudian and medical model perspective, emotional disengagement from the deceased was seen as essential to the successful adaptation of bereavement. A major shift in the bereavement literature has occurred and it is now generally accepted that despite the permanence of physical separation, the bereaved remains involved and connected to the deceased and can be emotionally sustained through continuing bonds. The majority of literature has focused on adults and on the nature of continuing bonds following the death of a spouse. In this article, the authors demonstrate how the continuing bonds concept applies to the sibling relationship. We describe the unique continued relationship formed by bereaved children and adolescents following a sibling loss, highlight the factors that influence the siblings continuing bonds expressions, and offer clinical interventions. In our view, mental health professionals can play an important role in helping parents encourage activities that may facilitate the creation and maintenance of continuing bonds in their children.

  4. [Bonding strength of resin and tooth enamel after teeth bleaching with cold plasma].

    PubMed

    Zhu, Meng-meng; Wang, Guo-min; Sun, Ke; Li, Ying-long; Pan, Jie

    2016-02-18

    To investigate the immediate bond strength and surface structure of resin and the tooth enamel which treated by cold plasma. In the study, 40 bovine incisors were divided into two equal parts. In this sense, all enamel adhesive samples were prepared and then randomly divided into 4 groups (n =20). group 1: acid + single bond 2+resin composite (control group); group 2:beyond bleaching+ acid+single bond 2+resin composite; group 3: treated by cold plasma for 5 minutes+ acid+single bond 2+resin composite; group 4: treated by cold plasma for 5 minutes+single bond 2+resin composite. Single bond 2 bonding system and Filtek Z250 resin were used in this experiment. The shear bond strength was tested by universal testing machine. The surface of the enamel in different processes was observed by scanning electron microscope (SEM). Statistical analyses by the single factor analysis of variance and multiple pairwise comparisons were performed with SPSS 17.0 . The shear bond strength of group 4 (8.60 MPa) was significantly lower than that of the other three groups (P<0.05). The shear bond strength of group 2 (17.89 MPa) was higher than that of group 4, but lower than group 1 and group 3 (P<0.05).There was no significant difference between group 1 (34.82 MPa) and group 3 (34.69 MPa). Scanning electron microscope indicated that the enamel treated by cold plasma had slight molten form, which was different from etched enamel surface.The fractured surface of group 3 was mix fracture, which was similar to the control group (group 1). Compared with the conventional clinic bleaching, immediate bond strength of resin-enamel that treated by cold plasma has not been affected.

  5. Erosive cola-based drinks affect the bonding to enamel surface: an in vitro study

    PubMed Central

    CASAS-APAYCO, Leslie Caroll; DREIBI, Vanessa Manzini; HIPÓLITO, Ana Carolina; GRAEFF, Márcia Sirlene Zardin; RIOS, Daniela; MAGALHÃES, Ana Carolina; BUZALAF, Marília Afonso Rabelo; WANG, Linda

    2014-01-01

    Objective This study aimed to assess the impact of in vitro erosion provoked by different cola-based drinks (Coke types), associated or not with toothbrushing, to bonding to enamel. Material and Methods Fifty-six bovine enamel specimens were prepared and randomly assigned into seven groups (N=8): C- Control (neither eroded nor abraded), ERO-RC: 3x/1-minute immersion in Regular Coke (RC), ERO-LC: 3x/1-minute immersion in Light Coke (LC), ERO-ZC: 3x/1-minute immersion in Zero Coke (ZC) and three other eroded groups, subsequently abraded for 1-minute toothbrushing (EROAB-RC, EROAB-LC and EROAB-ZC, respectively). After challenges, they were stored overnight in artificial saliva for a total of 24 hours and restored with Adper Single Bond 2/Filtek Z350. Buildup coronal surfaces were cut in 1 mm2 -specimens and subjected to a microtensile test. Data were statistically analyzed by two-way ANOVA/Bonferroni tests (α=0.05). Failure modes were assessed by optical microscopy (X40). The interface of the restorations were observed using Confocal Laser Scanning Microscopy (CLSM). Results All tested cola-based drinks significantly reduced the bond strength, which was also observed in the analyses of interfaces. Toothbrushing did not have any impact on the bond strength. CLSM showed that except for Zero Coke, all eroded specimens resulted in irregular hybrid layer formation. Conclusions All cola-based drinks reduced the bond strength. Different patterns of hybrid layers were obtained revealing their impact, except for ZC. PMID:24918663

  6. Factors affecting strategic plan implementation using interpretive structural modeling (ISM).

    PubMed

    Bahadori, Mohammadkarim; Teymourzadeh, Ehsan; Tajik, Hamidreza; Ravangard, Ramin; Raadabadi, Mehdi; Hosseini, Seyed Mojtaba

    2018-06-11

    Purpose Strategic planning is the best tool for managers seeking an informed presence and participation in the market without surrendering to changes. Strategic planning enables managers to achieve their organizational goals and objectives. Hospital goals, such as improving service quality and increasing patient satisfaction cannot be achieved if agreed strategies are not implemented. The purpose of this paper is to investigate the factors affecting strategic plan implementation in one teaching hospital using interpretive structural modeling (ISM). Design/methodology/approach The authors used a descriptive study involving experts and senior managers; 16 were selected as the study sample using a purposive sampling method. Data were collected using a questionnaire designed and prepared based on previous studies. Data were analyzed using ISM. Findings Five main factors affected strategic plan implementation. Although all five variables and factors are top level, "senior manager awareness and participation in the strategic planning process" and "creating and maintaining team participation in the strategic planning process" had maximum drive power. "Organizational structure effects on the strategic planning process" and "Organizational culture effects on the strategic planning process" had maximum dependence power. Practical implications Identifying factors affecting strategic plan implementation is a basis for healthcare quality improvement by analyzing the relationship among factors and overcoming the barriers. Originality/value The authors used ISM to analyze the relationship between factors affecting strategic plan implementation.

  7. 31 CFR 353.31 - Series HH bonds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the owner or coowner's account at a financial institution. Checks will be mailed to the delivery...) (c) Delivery of interest. Notices affecting the delivery of interest payments. To ensure appropriate action, notices affecting the delivery of interest payments on Series HH bonds must be received by the...

  8. Effect of additional etching and ethanol-wet bonding on the dentin bond strength of one-step self-etch adhesives

    PubMed Central

    Ahn, Joonghee; Jung, Kyoung-Hwa; Son, Sung-Ae; Hur, Bock; Kwon, Yong-Hoon

    2015-01-01

    Objectives This study examined the effects of additional acid etching on the dentin bond strength of one-step self-etch adhesives with different compositions and pH. The effect of ethanol wetting on etched dentin bond strength of self-etch adhesives was also evaluated. Materials and Methods Forty-two human permanent molars were classified into 21 groups according to the adhesive types (Clearfil SE Bond [SE, control]; G-aenial Bond [GB]; Xeno V [XV]; Beauti Bond [BB]; Adper Easy Bond [AE]; Single Bond Universal [SU]; All Bond Universal [AU]), and the dentin conditioning methods. Composite resins were placed on the dentin surfaces, and the teeth were sectioned. The microtensile bond strength was measured, and the failure mode of the fractured specimens was examined. The data were analyzed statistically using two-way ANOVA and Duncan's post hoc test. Results In GB, XV and SE (pH ≤ 2), the bond strength was decreased significantly when the dentin was etched (p < 0.05). In BB, AE and SU (pH 2.4 - 2.7), additional etching did not affect the bond strength (p > 0.05). In AU (pH = 3.2), additional etching increased the bond strength significantly (p < 0.05). When adhesives were applied to the acid etched dentin with ethanol-wet bonding, the bond strength was significantly higher than that of the no ethanol-wet bonding groups, and the incidence of cohesive failure was increased. Conclusions The effect of additional acid etching on the dentin bond strength was influenced by the pH of one-step self-etch adhesives. Ethanol wetting on etched dentin could create a stronger bonding performance of one-step self-etch adhesives for acid etched dentin. PMID:25671215

  9. Finite Element Bond Modeling for Indented Wires in Pretensioned Concrete Crossties

    DOT National Transportation Integrated Search

    2016-04-12

    Indented wires have been increasingly employed by : concrete crosstie manufacturers to improve the bond between : prestressing steel reinforcements and concrete, as bond can : affect several critical performance measures, including transfer : length,...

  10. Bond-strength inversion in (In,Ga)As semiconductor alloys

    NASA Astrophysics Data System (ADS)

    Eckner, Stefanie; Ritter, Konrad; Schöppe, Philipp; Haubold, Erik; Eckner, Erich; Rensberg, Jura; Röder, Robert; Ridgway, Mark C.; Schnohr, Claudia S.

    2018-05-01

    The atomic-scale structure and vibrational properties of semiconductor alloys are determined by the energy required for stretching and bending the individual bonds. Using temperature-dependent extended x-ray absorption fine-structure spectroscopy, we have determined the element-specific In-As and Ga-As effective bond-stretching force constants in (In,Ga)As as a function of the alloy composition. The results reveal a striking inversion of the bond strength where the originally stiffer bond in the parent materials becomes the softer bond in the alloy and vice versa. Our findings clearly demonstrate that changes of both the individual bond length and the surrounding matrix affect the bond-stretching force constants. We thus show that the previously used common assumptions about the element-specific force constants in semiconductor alloys do not reproduce the composition dependence determined experimentally for (In,Ga)As.

  11. Exploring paraprofessional and classroom factors affecting teacher supervision.

    PubMed

    Irvin, Dwight W; Ingram, Paul; Huffman, Jonathan; Mason, Rose; Wills, Howard

    2018-02-01

    Paraprofessionals serve a primary role in supporting students with disabilities in the classroom, which necessitates teachers' supervision as a means to improve their practice. Yet, little is known regarding what factors affect teacher supervision. We sought to identify how paraprofessional competence and classroom type affected the levels of teacher direction. We administered an adapted version of the Paraprofessional Needs, Knowledge & Tasks Survey and the Survey for Teachers Supervising Paraprofessionals to teachers supervising paraprofessionals in elementary schools. Structural Equation Modeling was used to examine the link between paraprofessional competence and classroom factors affecting the level of teacher supervision. Our results indicated that when teachers perceived paraprofessionals as being more skilled, they provided more supervision, and when more supervision was provided the less they thought paraprofessionals should be doing their assigned tasks. Additionally, paraprofessionals working in classrooms with more students with mild disabilities received less supervision than paraprofessionals working in classrooms with more students with moderate-to-severe disabilities. Those paraprofessionals in classrooms serving mostly children with mild disabilities were also perceived as having lower levels of skill competence than those serving in classrooms with students with more moderate-to-severe disabilities. By understanding the factors that affect teacher supervision, policy and professional development opportunities can be refined/developed to better support both supervising teachers and paraprofessionals and, in turn, improve the outcomes of children with disabilities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Ranking factors affecting emissions of GHG from incubated agricultural soils.

    PubMed

    García-Marco, S; Ravella, S R; Chadwick, D; Vallejo, A; Gregory, A S; Cárdenas, L M

    2014-07-01

    Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO 3 - ) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L 16 design, comprising 16 experimental units. Within this L 16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N 2 O), methane (CH 4 ) and carbon dioxide (CO 2 ) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO 3 - addition were the main factors affecting N 2 O fluxes, whilst glucose, NO 3 - and soil temperature were the main factors affecting CO 2 and CH 4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time.

  13. Ranking factors affecting emissions of GHG from incubated agricultural soils

    PubMed Central

    García-Marco, S; Ravella, S R; Chadwick, D; Vallejo, A; Gregory, A S; Cárdenas, L M

    2014-01-01

    Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO3−) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L16 design, comprising 16 experimental units. Within this L16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO3− addition were the main factors affecting N2O fluxes, whilst glucose, NO3− and soil temperature were the main factors affecting CO2 and CH4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time. PMID:25177207

  14. Prediction of fracture toughness and durability of adhesively bonded composite joints with undesirable bonding conditions

    NASA Astrophysics Data System (ADS)

    Musaramthota, Vishal

    Advanced composite materials have enabled the conventional aircraft structures to reduce weight, improve fuel efficiency and offer superior mechanical properties. In the past, materials such as aluminum, steel or titanium have been used to manufacture aircraft structures for support of heavy loads. Within the last decade or so, demand for advanced composite materials have been emerging that offer significant advantages over the traditional metallic materials. Of particular interest in the recent years, there has been an upsurge in scientific significance in the usage of adhesively bonded composite joints (ABCJ's). ABCJ's negate the introduction of stress risers that are associated with riveting or other classical techniques. In today's aircraft transportation market, there is a push to increase structural efficiency by promoting adhesive bonding to primary joining of aircraft structures. This research is focused on the issues associated with the durability and related failures in bonded composite joints that continue to be a critical hindrance to the universal acceptance of ABCJ's. Of particular interest are the short term strength, contamination and long term durability of ABCJ's. One of the factors that influence bond performance is contamination and in this study the influence of contamination on composite-adhesive bond quality was investigated through the development of a repeatable and scalable surface contamination procedure. Results showed an increase in the contaminant coverage area decreases the overall bond strength significantly. A direct correlation between the contaminant coverage area and the fracture toughness of the bonded joint was established. Another factor that influences bond performance during an aircraft's service life is its long term strength upon exposure to harsh environmental conditions or when subjected to severe mechanical loading. A test procedure was successfully developed in order to evaluate durability of ABCJ's comprising severe

  15. Association of HMO penetration and other credit quality factors with tax-exempt bond yields.

    PubMed

    McCue, M J

    1997-01-01

    This paper evaluates the relationship of HMO penetration, as well as other credit quality measures of market, institutional, operational, and financial traits, to tax-exempt bond yields. The study analyzed more than 1,500 bond issues from 1990 through 1993 and corrected for simultaneous relationships between bond size and yield and selection bias. The study found lower bond yields for hospitals located in markets with no HMO penetration. Lower yields for bond issues also were found for facilities generating higher numbers of days cash on hand and greater debt service coverage. Finally, results show that hospitals with higher occupancy rates achieve a lower yield.

  16. Importance of interlayer H bonding structure to the stability of layered minerals

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

    Conroy, Michele; Soltis, Jennifer A.; Wittman, Rick S.

    Layered (oxy) hydroxide minerals often possess out-of-plane hydrogen atoms that form hydrogen bonding networks which stabilize the layered structure. However, less is known about how the ordering of these bonds affects the structural stability and solubility of these minerals. Here, we report a new strategy that uses the focused electron beam to probe the effect of differences in hydrogen bonding networks on mineral solubility. In this regard, the dissolution behavior of boehmite (γ-AlOOH) and gibbsite (γ-Al(OH)3) were compared and contrasted in real time via liquid cell electron microscopy. Under identical such conditions, 2D-nanosheets of boehmite (γ-AlOOH) exfoliated from the bulkmore » and then rapidly dissolved, whereas gibbsite was stable. Further, substitution of only 1% Fe(III) for Al(III) in the structure of boehmite inhibited delamination and dissolution. Factors such as pH, radiolytic species, and knock on damage were systematically studied and eliminated as proximal causes for boehmite dissolution. Instead, the creation of electron/hole pairs was considered to be the mechanism that drove dissolution. The widely disparate behaviors of boehmite, gibbsite, and Fe-doped boehmite are discussed in the context of differences in the OH bond strengths, hydrogen bonding networks, and the presence or absence of electron/hole recombination centers.« less

  17. Importance of interlayer H bonding structure to the stability of layered minerals

    DOE PAGES

    Conroy, Michele; Soltis, Jennifer A.; Wittman, Rick S.; ...

    2017-10-16

    Layered (oxy) hydroxide minerals often possess out-of-plane hydrogen atoms that form hydrogen bonding networks which stabilize the layered structure. However, less is known about how the ordering of these bonds affects the structural stability and solubility of these minerals. Here, we report a new strategy that uses the focused electron beam to probe the effect of differences in hydrogen bonding networks on mineral solubility. In this regard, the dissolution behavior of boehmite (γ-AlOOH) and gibbsite (γ-Al(OH)3) were compared and contrasted in real time via liquid cell electron microscopy. Under identical such conditions, 2D-nanosheets of boehmite (γ-AlOOH) exfoliated from the bulkmore » and then rapidly dissolved, whereas gibbsite was stable. Further, substitution of only 1% Fe(III) for Al(III) in the structure of boehmite inhibited delamination and dissolution. Factors such as pH, radiolytic species, and knock on damage were systematically studied and eliminated as proximal causes for boehmite dissolution. Instead, the creation of electron/hole pairs was considered to be the mechanism that drove dissolution. The widely disparate behaviors of boehmite, gibbsite, and Fe-doped boehmite are discussed in the context of differences in the OH bond strengths, hydrogen bonding networks, and the presence or absence of electron/hole recombination centers.« less

  18. Reviews on factors affecting fatigue behavior of high-Mn steels

    NASA Astrophysics Data System (ADS)

    Kim, Sangshik; Jeong, Daeho; Sung, Hyokyung

    2018-01-01

    A variety of factors affect the fatigue behavior of high-Mn steels, which include both extrinsic (i.e., loading type, R ratio, specimen type, surface condition, temperature, and environment) and intrinsic (i.e., chemical composition, grain size, microstructure, stacking fault energy) factors. Very often, the influence of extrinsic factors on the fatigue behavior is even greater than that of intrinsic factors, misleading the interpretation of fatigue data. The metallurgical factors influence the initiation and propagation behaviors of fatigue by altering the characteristics of slip that is prerequisite for fatigue damage accumulation. It is however not easy to separate the effect of each factor since they affect the fatigue behavior of high-Mn steels in complex and synergistic way. In this review, the fatigue data of high-Mn steels are summarized and the factors complicating the interpretation are discussed.

  19. Review: Factors affecting fouling in conventional pens for slaughter pigs.

    PubMed

    Larsen, M L V; Bertelsen, M; Pedersen, L J

    2018-02-01

    This review assesses factors affecting fouling in conventional pens for slaughter pigs. Fouling of the pen happens when pigs change their excretory behaviour from occurring in the designated dunging area to the lying area. This can result in a lower hygiene, bad air quality, extra work for the farmer, disturbance of the pigs' resting behaviour and an increase in agonistic interactions. A systematic search was conducted and results narrowed down to 21 articles. Four factors were found to affect fouling directly: insufficient space allowance, the flooring design of the pen, the thermal climate and pigs' earlier experience. Further, these primary factors are affected by secondary factors such as the shape of the pen, the weight of the pigs and especially the heat balance of the pigs, which is affected by several tertiary factors including, for example, temperature, humidity and draught. Results indicate that the most important factor to control when trying to prevent fouling of a pen is the pen climate. An appropriate climate may be accomplished through floor cooling in the designated lying area, sprinklers above the designated dunging area and by ensuring a more optimal ambient temperature curve that also fits the weight of the pigs in different stages of the production. All in all, fouling of the pen in conventional slaughter pigs is a multifactorial problem, but it is important to focus on increasing the comfortability, and especially the climate, of the designated lying area.

  20. Bond-valence methods for pKa prediction. II. Bond-valence, electrostatic, molecular geometry, and solvation effects

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

    Bickmore, Barry R.; Rosso, Kevin M.; Tadanier, Christopher J.

    2006-08-15

    In a previous contribution, we outlined a method for predicting (hydr)oxy-acid and oxide surface acidity constants based on three main factors: bond valence, Me?O bond ionicity, and molecular shape. Here electrostatics calculations and ab initio molecular dynamics simulations are used to qualitatively show that Me?O bond ionicity controls the extent to which the electrostatic work of proton removal departs from ideality, bond valence controls the extent of solvation of individual functional groups, and bond valence and molecular shape controls local dielectric response. These results are consistent with our model of acidity, but completely at odds with other methods of predictingmore » acidity constants for use in multisite complexation models. In particular, our ab initio molecular dynamics simulations of solvated monomers clearly indicate that hydrogen bonding between (hydr)oxo-groups and water molecules adjusts to obey the valence sum rule, rather than maintaining a fixed valence based on the coordination of the oxygen atom as predicted by the standard MUSIC model.« less

  1. Bond performance of "Touch and Cure" adhesives on resin core systems.

    PubMed

    Kadowaki, Yoshitaka; Kakuda, Shinichi; Kawano, Shimpei; Katsumata, Aiichiro; Ting, Shihchun; Hoshika, Shuhei; Ikeda, Takatsumi; Tanaka, Toru; Carvalho, Ricardo Marinsde; Sano, Hidehiko

    2016-01-01

    The purpose of this study was to compare the micro-tensile bond strength (µTBS) of three resin core composites to dentin and to examine the bonded interface of the composites. One experimental TDK-03(TD) and, two commercial, DC core Automix One (DC) and Unifil core EM(UN) were used. Flat dentin surfaces of human molars were exposed using #600 SiC paper and bonded with the respective adhesive of each system. After bonding, the composites were built up on the surfaces and cured under two conditions: "light condition" or "dark condition". µTBSs (MPa) in the light condition were: TD; 60.02±17.08, DC; 38.21±13.70, and UN; 29.50±9.71; in the dark condition: TD; 54.62±17.11, DC; 8.40±4.81, and UN; 9.47±6.56. Dark curing negatively affected the bond strength of the two commercial resin-core materials. The experimental material was not affected by the curing conditions.

  2. Binding cooperativity between a ligand carbonyl group and a hydrophobic side chain can be enhanced by additional H-bonds in a distance dependent manner: A case study with thrombin inhibitors.

    PubMed

    Said, Ahmed M; Hangauer, David G

    2015-01-01

    One of the underappreciated non-covalent binding factors, which can significantly affect ligand-protein binding affinity, is the cooperativity between ligand functional groups. Using four different series of thrombin inhibitors, we reveal a strong positive cooperativity between an H-bond accepting carbonyl functionality and the adjacent P3 hydrophobic side chain. Adding an H-bond donating amine adjacent to the P3 hydrophobic side chain further increases this positive cooperativity thereby improving the Ki by as much as 546-fold. In contrast, adding an amidine multiple H-bond/salt bridge group in the distal S1 pocket does not affect this cooperativity. An analysis of the crystallographic B-factors of the ligand groups inside the binding site indicates that the strong cooperativity is mainly due to a significant mutual reduction in the residual mobility of the hydrophobic side chain and the H-bonding functionalities that is absent when the separation distance is large. This type of cooperativity is important to encode in binding affinity prediction software, and to consider in SAR studies. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  3. [Influence of thermalcycling on bonding durability of self-etch adhesives with dentin].

    PubMed

    Tian, Fu-cong; Wang, Xiao-yan; Gao, Xue-jun

    2014-04-18

    To investigate influence of thermalcycling on the bonding durability of two one-step products [Adper Prompt (AP) and G-bond (GB)] and one two-step self-etching adhesive [Clearfil SE bond (SE)] with dentin in vitro. Forty-two extracted human molars were selected. The superficial dentin was exposed by grinding off the enamel. The teeth were randomly distributed into six groups with varied bonding protocols. The adhesives were applied to the dentin surface. Composite crowns were built up, then the samples were cut longitudinally into sticks with 1.0 mm×1.0 mm bonding area [for microtensile bond strength (MTBS) testing] or 1.0 mm thick slabs (for nanoleakage observation). Bonding performance was evaluated with or without thermalcyling. For the MTBS testing, the strength values were statistically analysed using One-Way ANOVA. Four slabs in each group were observed for nanoleakage by SEM with a backscattered electron detector. Thermalcycling procedures affected MTBS. In the two one-step groups, the MTBS decreased significantly (P<0.05) after thermalcycling [AP group from (19.06±1.50) MPa to (12.62±2.10) MPa; GB group from (17.75±1.10) MPa to (6.24±0.42)MPa]. But in SE groups, MTBS did not significantly affect [(45.80±2.97) MPa compared with(40.60±5.76) MPa]. As a whole, one-step self-etching adhesives showed lower MTBS than two-step bonding system after aging.For AP and GB, continuous nanoleakage appearance was notable and more obvious than for SE. Thermalcycling can affect the bonding performance of self-etch adhesives including decrease of bond strength and nanoleakage pattern. one-step self-etch adhesives showed more obvious change compared with their two-step counterparts.

  4. Modified low-temperture direct bonding method for vacuum microelectronics application

    NASA Astrophysics Data System (ADS)

    Ju, Byeong-Kwon; Lee, Duck-Jung; Choi, Woo-Beom; Lee, Yun-Hi; Jang, Jin; Lee, Kwang-Bae; Oh, Myung-Hwan

    1997-06-01

    This paper presents the process and experimental results for the improved silicon-to-glass bonding using silicon direct bonding (SDB) followed by anodic bonding. The initial bonding between glass and silicon was caused by the hydrophilic surfaces of silicon-glass ensemble using SDB method. Then the initially bonded specimen had to be strongly bonded by anodic bonding process. The effects of the bonding process parameters on the interface energy were investigated as functions of the bonding temperature and voltage. We found that the specimen which was bonded using SDB process followed by anodic bonding process had higher interface energy than one using anodic bonding process only. The main factor contributing to the higher interface energy in the glass-to-silicon assemble bonded by SDB followed by anodic bonding was investigated by secondary ion mass spectroscopy analysis.

  5. Factors affecting the quality of life in childhood epilepsy in China.

    PubMed

    Yong, L; Chengye, J; Jiong, Q

    2006-03-01

    To explore the level of, and factors affecting the quality of life (QOL) in childhood epilepsy in China. At the Peking University First Hospital, we consecutively identified 418 parents whose children were with known epilepsy to complete a questionnaire, which included children's demographic characteristics, clinical message of epilepsy, QOL, familial message, parental symptoms of anxiety/depression. Significant (p<0.05) affecting factors of children's quality of life included current educational degree, mental development, age at diagnosis, age at onset, seizure frequency, duration, AED number; parental significant (p<0.05) affecting factors included anxiety, depression and health. On regression analysis, parental anxiety was the most important factor in explaining lower QOL in childhood epilepsy. AEDs, familial economic state, paternal career, seizure frequency were also significant factors. Parental anxiety outweighed the physical factors in determining QOL in childhood epilepsy. Recognition of this will be helpful for professionals to treat disease and improve the QOL of childhood epilepsy.

  6. Knowing the Odds: Parameters that Predict Passing or Failing School District Bonds

    ERIC Educational Resources Information Center

    Bowers, Alex J.; Metzger, Scott Alan; Militello, Matthew

    2010-01-01

    This study investigates parameters affecting the likelihood of passing school facility construction bonds by local district election. Using statewide data from Michigan, this study analyzes school bond data for urban (n = 30), suburban (n = 164), small town (n = 70), and rural (n = 241) school districts that held capital improvement bond elections…

  7. Factors affecting academic leadership in dermatology.

    PubMed

    Martires, Kathryn J; Aquino, Lisa L; Wu, Jashin J

    2015-02-01

    Although prior studies have examined methods by which to recruit and retain academic dermatologists, few have examined factors that are important for developing academic leaders in dermatology. This study sought to examine characteristics of dermatology residency programs that affect the odds of producing department or division chairs/chiefs and program directors (PDs). Data regarding program size, faculty, grants, alumni residency program attended, lectures, and publications for all accredited US dermatology residency programs were collected. Of the 103 programs examined, 46% had graduated at least 1 chair/chief, and 53% had graduated at least 1 PD. Results emphasize that faculty guidance and research may represent modifiable factors by which a dermatology residency program can increase its graduation of academic leaders.

  8. DRD4 Polymorphism Moderates the Effect of Alcohol Consumption on Social Bonding

    PubMed Central

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

    2012-01-01

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

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

    PubMed

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

    2012-01-01

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

  10. 78 FR 46418 - Proposed Information Collection (Obligation To Report Factors Affecting Entitlement) Activity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... (Obligation To Report Factors Affecting Entitlement) Activity; Comment Request AGENCY: Veterans Benefits... use of other forms of information technology. Title: Obligation to Report Factors Affecting... entitlement factors. Individual factors such as income, marital status, and the beneficiary's number of...

  11. 75 FR 62634 - Proposed Information Collection (Obligation to Report Factors Affecting Entitlement) Activity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... (Obligation to Report Factors Affecting Entitlement) Activity: Comment Request AGENCY: Veterans Benefits... use of other forms of information technology. Title: Obligation to Report Factors Affecting... entitlement factors. Individual factors such as income, marital status, and the beneficiary's number of...

  12. Analysis of factors affecting employee satisfaction: A case study from Pakistan.

    PubMed

    Rukh, Lala; Choudhary, Muhammad Abbas; Abbasi, Saddam Akber

    2015-01-01

    Employee job satisfaction has been a research focal point throughout the world. It is a key factor when measuring the performance of an organization and individuals. A leading engineering goods manufacturing enterprise in Pakistan, has been used in this case study. In Pakistan, very limited research has been done with respect to factors affecting job satisfaction. Some research has been done in medical institutions, banks, universities and the information technology sector but large public sector organizations in Pakistan have not been studied. A theoretical foundation for researching factors affecting job satisfaction in large organizations is outlined. The objective of this research is to analyze various demographic, financial and non-financial factors affecting the satisfaction level of employees and to study the effects across different employee groups. This study is based on quantitative data analysis. The employees of the organization under study have been divided into 10 homogeneous groups based on their departments. Information on job related factors (affecting the satisfaction level) have been collected from subsamples of each group using a self-administered questionnaire. An overall sample of 250 (out of total 1100) employees has been selected. Before conducting the survey, reliability of the questionnaire was measured using Cronbach's alpha. The normality of data was also examined using the Kolmogorov Smirnov test. Hypotheses devised to address the research questions were tested by using non-parametric Spearman correlation and Kruskal-Wallis tests. The response rate was 73.2%. Research findings indicated the significant factors that affect the satisfaction level of employees. Median group differences existed between responses based on age, work experience, salary and designation (i.e. job position/rank) of employees. Job satisfaction was also positively and significantly associated with job related factors such as pay, promotion, relation with employees

  13. Factors Affecting Successful Implementation of Hospital Information Systems.

    PubMed

    Farzandipur, Mehrdad; Jeddi, Fatemeh Rangraz; Azimi, Esmaeil

    2016-02-01

    Today, the use of information systems in health environments, like any other fields, is necessary and organizational managers are convinced to use these systems. However, managers' satisfaction is not the only factor in successfully implementing these systems and failed information technology projects (IT) are reported despite the consent of the directors. Therefore, this study aims to determine the factors affecting the successful implementation of a hospital information system. The study was carried out as a descriptive method in 20 clinical hospitals that the hospital information system (HIS) was conducted in them. The clinical and paraclinical users of mentioned hospitals are the study group. 400 people were chosen as samples in scientific method and the data was collected using a questionnaire consisted of three main human, managerial and organizational, and technological factors, by questionnaire and interview. Then the data was scored in Likert scale (score of 1 to 5) and were analyzed using the SPSS software. About 75 percent of the population were female, with average work experience of 10 years and the mean age was 30 years. The human factors affecting the success of hospital information system implementation achieved the mean score of 3.5, both organizational and managerial factors 2.9 and technological factors the mean of 3. Human factors including computer skills, perceiving usefulness and perceiving the ease of a hospital information system use are more effective on the acceptance and successful implementation of hospital information systems; then the technological factors play a greater role. It is recommended that for the successful implementation of hospital information systems, most of these factors to be considered.

  14. Factors Affecting Open-Set Word Recognition in Adults with Cochlear Implants

    PubMed Central

    Holden, Laura K.; Finley, Charles C.; Firszt, Jill B.; Holden, Timothy A.; Brenner, Christine; Potts, Lisa G.; Gotter, Brenda D.; Vanderhoof, Sallie S.; Mispagel, Karen; Heydebrand, Gitry; Skinner, Margaret W.

    2012-01-01

    A monosyllabic word test was administered to 114 postlingually-deaf adult cochlear implant (CI) recipients at numerous intervals from two weeks to two years post-initial CI activation. Biographic/audiologic information, electrode position, and cognitive ability were examined to determine factors affecting CI outcomes. Results revealed that Duration of Severe-to-Profound Hearing Loss, Age at Implantation, CI Sound-field Threshold Levels, Percentage of Electrodes in Scala Vestibuli, Medio-lateral Electrode Position, Insertion Depth, and Cognition were among the factors that affected performance. Knowledge of how factors affect performance can influence counseling, device fitting, and rehabilitation for patients and may contribute to improved device design. PMID:23348845

  15. Factors affecting self-regulated learning in medical students: a qualitative study

    PubMed Central

    Jouhari, Zahra; Haghani, Fariba; Changiz, Tahereh

    2015-01-01

    Introduction Clinical courses are required of all medical students and means that they must develop the key skill of self-regulation during learning. The ability to self-regulate learning strategies is affected by different factors. This study determined the views of medical students on the factors affecting self-regulated learning (SRL). Method This study uses a qualitative approach and the content analysis method. Nineteen medical students in their fourth, fifth, and sixth years of study at Isfahan University of Medical Science participated in semi-structured, in-depth interviews. The students were selected using purposive sampling based on their overall grade point average (GPA). Results Five main themes were found to affect SRL. These themes included family with the two subthemes of family supervisory and supportive roles; peers with the two subthemes of facilitating and inhibiting roles; instructors with the two subthemes of personal and educational instructor's characteristics; educational environment with the two subthemes of facilitator and inhibitor roles; and student with the two subthemes of facilitating and inhibiting personal factors. Conclusion The outcomes of student understanding of the factors affecting self-regulation indicate that facilitating factors should be used on an individual basis to reduce the effect of inhibiting factors to improve self-regulation in students. PMID:26549046

  16. Factors affecting self-regulated learning in medical students: a qualitative study.

    PubMed

    Jouhari, Zahra; Haghani, Fariba; Changiz, Tahereh

    2015-01-01

    Introduction Clinical courses are required of all medical students and means that they must develop the key skill of self-regulation during learning. The ability to self-regulate learning strategies is affected by different factors. This study determined the views of medical students on the factors affecting self-regulated learning (SRL). Method This study uses a qualitative approach and the content analysis method. Nineteen medical students in their fourth, fifth, and sixth years of study at Isfahan University of Medical Science participated in semi-structured, in-depth interviews. The students were selected using purposive sampling based on their overall grade point average (GPA). Results Five main themes were found to affect SRL. These themes included family with the two subthemes of family supervisory and supportive roles; peers with the two subthemes of facilitating and inhibiting roles; instructors with the two subthemes of personal and educational instructor's characteristics; educational environment with the two subthemes of facilitator and inhibitor roles; and student with the two subthemes of facilitating and inhibiting personal factors. Conclusion The outcomes of student understanding of the factors affecting self-regulation indicate that facilitating factors should be used on an individual basis to reduce the effect of inhibiting factors to improve self-regulation in students.

  17. Factors affecting self-regulated learning in medical students: a qualitative study.

    PubMed

    Jouhari, Zahra; Haghani, Fariba; Changiz, Tahereh

    2015-01-01

    Clinical courses are required of all medical students and means that they must develop the key skill of self-regulation during learning. The ability to self-regulate learning strategies is affected by different factors. This study determined the views of medical students on the factors affecting self-regulated learning (SRL). This study uses a qualitative approach and the content analysis method. Nineteen medical students in their fourth, fifth, and sixth years of study at Isfahan University of Medical Science participated in semi-structured, in-depth interviews. The students were selected using purposive sampling based on their overall grade point average (GPA). Five main themes were found to affect SRL. These themes included family with the two subthemes of family supervisory and supportive roles; peers with the two subthemes of facilitating and inhibiting roles; instructors with the two subthemes of personal and educational instructor's characteristics; educational environment with the two subthemes of facilitator and inhibitor roles; and student with the two subthemes of facilitating and inhibiting personal factors. The outcomes of student understanding of the factors affecting self-regulation indicate that facilitating factors should be used on an individual basis to reduce the effect of inhibiting factors to improve self-regulation in students.

  18. 14 CFR Appendix B to Part 1215 - Factors Affecting Standard Charges

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Factors Affecting Standard Charges B Appendix B to Part 1215 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION TRACKING AND DATA RELAY SATELLITE SYSTEM (TDRSS) Pt. 1215, App. B Appendix B to Part 1215—Factors Affecting Standard...

  19. Shear bond strength of composite bonded with three adhesives to Er,Cr:YSGG laser-prepared enamel.

    PubMed

    Türkmen, Cafer; Sazak-Oveçoğlu, Hesna; Günday, Mahir; Güngör, Gülşad; Durkan, Meral; Oksüz, Mustafa

    2010-06-01

    To assess in vitro the shear bond strength of a nanohybrid composite resin bonded with three adhesive systems to enamel surfaces prepared with acid and Er,Cr:YSGG laser etching. Sixty extracted caries- and restoration-free human maxillary central incisors were used. The teeth were sectioned 2 mm below the cementoenamel junction. The crowns were embedded in autopolymerizing acrylic resin with the labial surfaces facing up. The labial surfaces were prepared with 0.5-mm reduction to receive composite veneers. Thirty specimens were etched with Er,Cr:YSGG laser. This group was also divided into three subgroups, and the following three bonding systems were then applied on the laser groups and the other three unlased groups: (1) 37% phosphoric acid etch + Bond 1 primer/adhesive (Pentron); (2) Nano-bond self-etch primer (Pentron) + Nano-bond adhesive (Pentron); and (3) all-in-one adhesive-single dose (Futurabond NR, Voco). All of the groups were restored with a nanohybrid composite resin (Smile, Pentron). Shear bond strength was measured with a Zwick universal test device with a knife-edge loading head. The data were analyzed with two-factor ANOVA. There were no significant differences in shear bond strength between self-etch primer + adhesive and all-in-one adhesive systems for nonetched and laser-etched enamel groups (P > .05). However, bond strength values for the laser-etched + Bond 1 primer/adhesive group (48.00 +/- 13.86 MPa) were significantly higher than the 37% phosphoric acid + Bond 1 primer/adhesive group (38.95 +/- 20.07 MPa) (P < .05). The Er,Cr:YSGG laser-powered hydrokinetic system etched the enamel surface more effectively than 37% phosphoric acid for subsequent attachment of composite material.

  20. The social life of bonding theory.

    PubMed

    Crouch, M; Manderson, L

    1995-09-01

    'Bonding' as a crucial factor of the early post-partum entered obstetric and paediatric practice after the publication of Maternal and Infant Bonding in 1976 by Klaus and Kennell. The concept has held its place since, as witnessed by medical textbook accounts of it, and the perception of 'instantaneous bonding' as a vital component of the ideal birth experience has dominated media representations of childbirth and, until very recently, feminist writing. Only during the last few years has this literature taken into account research findings concerning the guilt and anxiety experienced by women whose expectations regarding 'bonding' are not realised. While it is now generally acknowledged that maternal attachment develops over an extended period of time, 'bonding' as used extensively in both popular and scientific literature conflates a wide range of meanings and blurs the boundaries between process and outcome. This facilitates the entry of ideological elements into a field which is, by its very nature, deeply significant for human experience. We therefore argue for a continuing critical appraisal of the role of 'bonding' in both general and scientific research.

  1. Methods of Combinatorial Optimization to Reveal Factors Affecting Gene Length

    PubMed Central

    Bolshoy, Alexander; Tatarinova, Tatiana

    2012-01-01

    In this paper we present a novel method for genome ranking according to gene lengths. The main outcomes described in this paper are the following: the formulation of the genome ranking problem, presentation of relevant approaches to solve it, and the demonstration of preliminary results from prokaryotic genomes ordering. Using a subset of prokaryotic genomes, we attempted to uncover factors affecting gene length. We have demonstrated that hyperthermophilic species have shorter genes as compared with mesophilic organisms, which probably means that environmental factors affect gene length. Moreover, these preliminary results show that environmental factors group together in ranking evolutionary distant species. PMID:23300345

  2. Measuring Treasury Bond Portfolio Risk and Portfolio Optimization with a Non-Gaussian Multivariate Model

    NASA Astrophysics Data System (ADS)

    Dong, Yijun

    The research about measuring the risk of a bond portfolio and the portfolio optimization was relatively rare previously, because the risk factors of bond portfolios are not very volatile. However, this condition has changed recently. The 2008 financial crisis brought high volatility to the risk factors and the related bond securities, even if the highly rated U.S. treasury bonds. Moreover, the risk factors of bond portfolios show properties of fat-tailness and asymmetry like risk factors of equity portfolios. Therefore, we need to use advanced techniques to measure and manage risk of bond portfolios. In our paper, we first apply autoregressive moving average generalized autoregressive conditional heteroscedasticity (ARMA-GARCH) model with multivariate normal tempered stable (MNTS) distribution innovations to predict risk factors of U.S. treasury bonds and statistically demonstrate that MNTS distribution has the ability to capture the properties of risk factors based on the goodness-of-fit tests. Then based on empirical evidence, we find that the VaR and AVaR estimated by assuming normal tempered stable distribution are more realistic and reliable than those estimated by assuming normal distribution, especially for the financial crisis period. Finally, we use the mean-risk portfolio optimization to minimize portfolios' potential risks. The empirical study indicates that the optimized bond portfolios have better risk-adjusted performances than the benchmark portfolios for some periods. Moreover, the optimized bond portfolios obtained by assuming normal tempered stable distribution have improved performances in comparison to the optimized bond portfolios obtained by assuming normal distribution.

  3. Durable wood bonding with epoxy adhesives

    Treesearch

    Charles R. Frihart

    2003-01-01

    Although wood was one of the earliest materials to be adhesively bonded, the factors that contribute to strong wood bonds are still not well understood. Wood is a very complex substrate in that it is non-uniform in most aspects. On the macro scale, it is a porous structure with different sized and shaped voids for fluid flow. The structural cells contain four different...

  4. Bonding measurement -Strength and fracture mechanics approaches.

    PubMed

    Anunmana, Chuchai; Wansom, Wiroj

    2017-07-26

    This study investigated the effect of cross-sectional areas on interfacial fracture toughness and bond strength of bilayered dental ceramics. Zirconia core ceramics were veneered and cut to produce specimens with three different cross-sectional areas. Additionally, monolithic specimens of glass veneer were also prepared. The specimens were tested in tension until fracture at the interface and reported as bond strength. Fracture surfaces were observed, and the apparent interfacial toughness was determined from critical crack size and failure stress. The results showed that cross-sectional area had no effect on the interfacial toughness whereas such factor had a significant effect on interfacial bond strength. The study revealed that cross-sectional area had no effect on the interfacial toughness, but had a significant effect on interfacial bond strength. The interfacial toughness may be a more reliable indicator for interfacial bond quality than interfacial bond strength.

  5. Effect of chlorhexidine pretreatment on bond strength durability of caries-affected dentin over 2-year aging in artificial saliva and under simulated intrapulpal pressure.

    PubMed

    Mobarak, E H

    2011-01-01

    To evaluate the influence of 2% and 5% chlorhexidine (CHX) pretreatment on bond durability of a self-etching adhesive to normal (ND) and caries-affected (AD) dentin after 2-years of aging in artificial saliva and under simulated intrapulpal pressure (IPP). One hundred twenty freshly extracted carious teeth were ground to expose ND and AD. Specimens were distributed into three equal groups (n=40) according to whether the dentin substrates were pretreated with 2% or 5% CHX or with water (control). Clearfil SE Bond (Kuraray) was applied to both substrates and composite cylinders (0.9 mm diameter and 0.7 mm height) were formed. Pretreatment and bonding were done while the specimens were subjected to 15 mm Hg IPP. After curing, specimens were aged in artificial saliva at 37°C and under IPP at 20 mm Hg until being tested after 24 hours or 2 years (n=20/group). Microshear bond strength was evaluated. Failure modes were determined using a scanning electron microscope (SEM) at 400× magnification. Data were statistically analyzed using three-way analysis of variance (ANOVA); one-way ANOVA tests, and t-test (p<0.05). Additional specimens (n=5/group) were prepared to evaluate interfacial silver precipitation. For the 24-hour groups, there were no significant differences among the ND groups and AD groups. For ND aged specimens, the 5% CHX group had the highest value followed by the 2% CHX and control groups, although the difference was statistically insignificant. For AD aged specimens, the 5% CHX group revealed statistically higher bond values compared to the 2% CHX and control groups. Fracture modes were predominately adhesive and mixed. Different interfacial silver depositions were recorded. Two percent or 5% CHX pretreatment has no adverse effect on the 24-hour bonding to ND and AD. Five percent CHX was able to diminish the loss in bonding to AD after 2years of aging in artificial saliva and under simulated IPP.

  6. Shear bond strength of resin composite bonded with two adhesives: Influence of Er: YAG laser irradiation distance

    PubMed Central

    Shirani, Farzaneh; Birang, Reza; Malekipour, Mohammad Reza; Hourmehr, Zahra; Kazemi, Shantia

    2014-01-01

    Background: Dental surfaces prepared with different Er:YAG laser distance may have different characteristics compared with those prepared with conventional instruments. The aim of this study was to investigate the effect of Er:YAG laser irradiation distance from enamel and dentin surfaces on the shear bond strength of composite with self-etch and etch and rinse bonding systems compared with conventional preparation method. Materials and Methods: Two hundred caries-free human third molars were randomly divided into twenty groups (n = 10). Ten groups were designated for enamel surface (E1-E10) and ten for dentin surface (D1-D10). Er: YAG laser (2940 nm) was used on the E1-E8 (240 mJ, 25 Hz) and D1-D8 (140 mJ, 30 Hz) groups at four different distances of 0.5 (standard), 2, 4 and 11 mm. Control groups (E9, E10, D9 and D10) were ground with medium grit diamond bur. The enamel and dentin specimens were divided into two subgroups that were bonded with either Single Bond or Clearfil SE Bond. Resin composite (Z100) was dispensed on prepared dentin and enamel. The shear bond strengths were tested using a universal testing machine. Data were analyzed by SPSS12 statistical software using three way analysis of variance, Tukey and independent t-test. P < 0.05 was considered as significant. Results: There was a significant difference between enamel and dentin substrates (P < 0.001) and between lased and un-lased groups; the un-lased group had significantly higher bond strength (P < 0.001). Shear bond strength increased significantly with an increase in the laser irradiation distance (P < 0.05) on enamel surfaces (in both bonding agent subgroups) and on dentin surfaces (in the Single Bond subgroup). Conclusion: Laser irradiation decreases shear bond strength. Irradiation distance affects shear bond strength and increasing the distance would decrease the negative effects of laser irradiation. PMID:25540665

  7. Factors Affecting Smoking Tendency and Smoking Intensity

    ERIC Educational Resources Information Center

    David, Nissim Ben; Zion, Uri Ben

    2009-01-01

    Purpose: The purpose of this paper is to measure the relative effect of relevant explanatory variable on smoking tendency and smoking intensity. Design/methodology/approach: Using survey data collected by the Israeli Bureau of Statistics in 2003-2004, a probit procedure is estimated for analyzing factors that affect the probability of being a…

  8. σ-Hole Bond vs π-Hole Bond: A Comparison Based on Halogen Bond.

    PubMed

    Wang, Hui; Wang, Weizhou; Jin, Wei Jun

    2016-05-11

    The σ-hole and π-hole are the regions with positive surface electrostatic potential on the molecule entity; the former specifically refers to the positive region of a molecular entity along extension of the Y-Ge/P/Se/X covalent σ-bond (Y = electron-rich group; Ge/P/Se/X = Groups IV-VII), while the latter refers to the positive region in the direction perpendicular to the σ-framework of the molecular entity. The directional noncovalent interactions between the σ-hole or π-hole and the negative or electron-rich sites are named σ-hole bond or π-hole bond, respectively. The contributions from electrostatic, charge transfer, and other terms or Coulombic interaction to the σ-hole bond and π-hole bond were reviewed first followed by a brief discussion on the interplay between the σ-hole bond and the π-hole bond as well as application of the two types of noncovalent interactions in the field of anion recognition. It is expected that this review could stimulate further development of the σ-hole bond and π-hole bond in theoretical exploration and practical application in the future.

  9. Effect of indirect composite treatment microtensile bond strength of self-adhesive resin cements

    PubMed Central

    Escribano, Nuria; Baracco, Bruno; Romero, Martin; Ceballos, Laura

    2016-01-01

    Background No specific indications about the pre-treatment of indirect composite restorations is provided by the manufacturers of most self-adhesive resin cements. The potential effect of silane treatment to the bond strength of the complete tooth/indirect restoration complex is not available.The aim of this study was to determine the contribution of different surface treatments on microtensile bond strength of composite overlays to dentin using several self-adhesive resin cements and a total-etch one. Material and Methods Composite overlays were fabricated and bonding surfaces were airborne-particle abraded and randomly assigned to two different surface treatments: no treatment or silane application (RelyX Ceramic Primer) followed by an adhesive (Adper Scotchbond 1 XT). Composite overlays were luted to flat dentin surfaces using the following self-adhesive resin cements: RelyX Unicem, G-Cem, Speedcem, Maxcem Elite or Smartcem2, and the total-etch resin cement RelyX ARC. After 24 h, bonded specimens were cut into sticks 1 mm thick and stressed in tension until failure. Two-way ANOVA and SNK tests were applied at α=0.05. Results Bond strength values were significantly influenced by the resin cement used (p<0.001). However, composite surface treatment and the interaction between the resin cement applied and surface treatment did not significantly affect dentin bond strength (p>0.05). All self-adhesive resin cements showed lower bond strength values than the total-etch RelyX ARC. Among self-adhesive resin cements, RelyX Unicem and G-Cem attained statistically higher bond strength values. Smartcem2 and Maxcem Elite exhibited 80-90% of pre-test failures. Conclusions The silane and adhesive application after indirect resin composite sandblasting did not improve the bond strength of dentin-composite overlay complex. Selection of the resin cement seems to be a more relevant factor when bonding indirect composites to dentin than its surface treatment. Key words:Bond

  10. Technique sensitivity in bonding to enamel and dentin.

    PubMed

    Powers, John M; Farah, John W

    2010-09-01

    Bonding to enamel and dentin has been among the most significant advancements in dentistry in the last five decades; extensive research and product development have resulted in more adhesive options. However, bonding to enamel and dentin still proves to be challenging, and selecting the correct product for a clinical application can be confusing. An incorrect choice can lead to insufficient bond strength. Day-to-day clinical factors, such as the presence of enamel, superficial dentin, or carious dentin, as well as contamination by saliva, blood, or bleaching agents, can cause bonding agents to be technique sensitive-they may fail prematurely if steps are not followed meticulously. This article attempts to simplify the selection process for enamel and dentinal bonding and summarize clinically relevant bonding information that will help produce consistently successful results.

  11. Identification of Factors That Affect Software Complexity.

    ERIC Educational Resources Information Center

    Kaiser, Javaid

    A survey of computer scientists was conducted to identify factors that affect software complexity. A total of 160 items were selected from the literature to include in a questionnaire sent to 425 individuals who were employees of computer-related businesses in Lawrence and Kansas City. The items were grouped into nine categories called system…

  12. INTERNATIONAL DIFFERENCES IN FACTORS AFFECTING LABOUR MOBILITY.

    ERIC Educational Resources Information Center

    SELLIER, F.; ZARKA, C.

    THE GEOGRAPHICAL, OCCUPATIONAL, AND INTERFIRM MOBILITY, AND THE FACTORS AFFECTING THESE MOVEMENTS FOR WORKERS IN FRANCE, ITALY, GERMANY, AND SWEDEN IN THE PERIOD SINCE THE SECOND WORLD WAR ARE STUDIED. DATA OBTAINED FROM INDUSTRIAL SURVEYS AND GENERAL CENSUSES WERE USED TO COMPARE THE FOUR COUNTRIES WITH EACH OTHER AND WITH THE UNITED STATES.…

  13. Factors Contributing to Students' Misconceptions in Learning Covalent Bonds

    ERIC Educational Resources Information Center

    Erman, Erman

    2017-01-01

    This study aims to identify students' misconceptions regarding covalent bonds. Seventy-seven graduate students in the middle of Indonesia participated in the study. Data were collected in three stages. First, misconceptions were identified by using the Semi Open Diagnostic Test. Ten students who experienced the worst misconceptions were…

  14. A Metasynthesis of Factors Affecting Self-Management of Chronic Illness

    PubMed Central

    SCHULMAN-GREEN, Dena; JASER, Sarah S.; PARK, Chorong; WHITTEMORE, Robin

    2015-01-01

    Aim To identify factors that may serve as facilitators and barriers to self-management described by adults living with chronic illness by conducting a qualitative metasynthesis. Background Self-management is an individuals’ active management of a chronic illness in collaboration with their family members and clinicians. Design Qualitative metasynthesis. Data Sources We analyzed studies (N=53) published between January 2000–May 2013 that described factors affecting self-management in chronic illness as reported by adults aged over 18 years with chronic illness. Review Methods Sandelowsi and Barroso approach to qualitative metasynthesis: literature search; quality appraisal; analysis; and synthesis of findings. Results Collectively, article authors reported on sixteen chronic illnesses, most commonly diabetes (N=28) and cardiovascular disease (N=20). Participants included men and women (mean age=57, range 18–94) from twenty countries representing diverse races and ethnicities. We identified five categories of factors affecting self-management: Personal/Lifestyle Characteristics; Health Status; Resources; Environmental Characteristics; and Health Care System. Factors may interact to affect self-management and may exist on a continuum of positive (facilitator) to negative (barrier). Conclusion Understanding factors that influence self-management may improve assessment of self-management among adults with chronic illness and may inform interventions tailored to meet individuals’ needs and improve health outcomes. PMID:26781649

  15. Factors affecting post-pubertal penile size in patients with hypospadias.

    PubMed

    Moriya, Kimihiko; Nakamura, Michiko; Nishimura, Yoko; Kitta, Takeya; Kanno, Yukiko; Chiba, Hiroki; Kon, Masafumi; Shinohara, Nobuo

    2016-09-01

    To evaluate actual post-pubertal penile size and factors affecting it in hypospadias patients, we retrospectively reviewed medical charts. Hypospadias patients whose external genitalia were categorized into Tanner stage 5, and whose stretched penile length was evaluated at 15 years old or older from April 2008 to April 2015, were enrolled in the present study. Stretched penile length was measured by a single examiner. Actual post-pubertal stretched penile length and factors affecting the post-pubertal stretched penile length were estimated. Statistical analysis was performed using Mann-Whitney U test and univariate and multivariate linear regression models for the determination of independent factors. Thirty patients met the inclusion criteria. Median age at evaluation was 17.2 years. Thirteen and 17 had mild and severe hypospadias, respectively. Endocrinological abnormality was identified in 5. Multivariate analysis showed that the severity of hypospadias and endocrinological abnormality were significant factors affecting stretched penile length. Stretched penile length in 25 patients without endocrinological abnormality was significantly longer than that in those with endocrinological abnormality (p = 0.036). Among patients without endocrinological abnormality, stretched penile length in 13 with severe hypospadias was significantly shorter than that in 12 with mild hypospadias (p = 0.004). While the severity of hypospadias and endocrinological abnormality at post-pubertal evaluation were factors affecting post-pubertal penile size, stretched penile length in patients with severe hypospadias was shorter even in cases without endocrinological abnormality. These results suggest that severe hypospadias is not only a disorder of urethral development, but also a disorder of penile development.

  16. Hydrogen bond and halogen bond inside the carbon nanotube

    NASA Astrophysics Data System (ADS)

    Wang, Weizhou; Wang, Donglai; Zhang, Yu; Ji, Baoming; Tian, Anmin

    2011-02-01

    The hydrogen bond and halogen bond inside the open-ended single-walled carbon nanotubes have been investigated theoretically employing the newly developed density functional M06 with the suitable basis set and the natural bond orbital analysis. Comparing with the hydrogen or halogen bond in the gas phase, we find that the strength of the hydrogen or halogen bond inside the carbon nanotube will become weaker if there is a larger intramolecular electron-density transfer from the electron-rich region of the hydrogen or halogen atom donor to the antibonding orbital of the X-H or X-Hal bond involved in the formation of the hydrogen or halogen bond and will become stronger if there is a larger intermolecular electron-density transfer from the electron-rich region of the hydrogen or halogen atom acceptor to the antibonding orbital of the X-H or X-Hal bond. According to the analysis of the molecular electrostatic potential of the carbon nanotube, the driving force for the electron-density transfer is found to be the negative electric field formed in the carbon nanotube inner phase. Our results also show that the X-H bond involved in the formation of the hydrogen bond and the X-Hal bond involved in the formation of the halogen bond are all elongated when encapsulating the hydrogen bond and halogen bond within the carbon nanotube, so the carbon nanotube confinement may change the blue-shifting hydrogen bond and the blue-shifting halogen bond into the red-shifting hydrogen bond and the red-shifting halogen bond. The possibility to replace the all electron nanotube-confined calculation by the simple polarizable continuum model is also evaluated.

  17. Durable bonds at the adhesive/dentin interface: an impossible mission or simply a moving target?

    PubMed Central

    SPENCER, Paulette; Jonggu PARK, Qiang YE; MISRA, Anil; BOHATY, Brenda S.; SINGH, Viraj; PARTHASARATHY, Ranga; SENE, Fábio; de Paiva GONÇALVES, Sérgio Eduardo; LAURENCE, Jennifer

    2013-01-01

    Composite restorations have higher failure rates, more recurrent caries and increased frequency of replacement as compared to dental amalgam. Penetration of bacterial enzymes, oral fluids, and bacteria into the crevices between the tooth and composite undermines the restoration and leads to recurrent decay and failure. The gingival margin of composite restora tions is particularly vulnerable to decay and at this margin, the adhesive and its seal to dentin provides the primary barrier between the prepared tooth and the environment. The intent of this article is to examine physico-chemical factors that affect the integrity and durability of the adhesive/dentin interfacial bond; and to explore how these factors act synergistically with mechanical forces to undermine the composite restoration. The article will examine the various avenues that have been pursued to address these problems and it will explore how alterations in material chemistry could address the detrimental impact of physico-chemical stresses on the bond formed at the adhesive/dentin interface. PMID:24855586

  18. Factors affecting rotator cuff healing.

    PubMed

    Mall, Nathan A; Tanaka, Miho J; Choi, Luke S; Paletta, George A

    2014-05-07

    Several studies have noted that increasing age is a significant factor for diminished rotator cuff healing, while biomechanical studies have suggested the reason for this may be an inferior healing environment in older patients. Larger tears and fatty infiltration or atrophy negatively affect rotator cuff healing. Arthroscopic rotator cuff repair, double-row repairs, performing a concomitant acromioplasty, and the use of platelet-rich plasma (PRP) do not demonstrate an improvement in structural healing over mini-open rotator cuff repairs, single-row repairs, not performing an acromioplasty, or not using PRP. There is conflicting evidence to support postoperative rehabilitation protocols using early motion over immobilization following rotator cuff repair.

  19. Factors affecting corticosteroid concentrations in yellow-bellied marmots.

    PubMed

    Armitage, K B

    1991-01-01

    1. Bound and total corticosteroid concentrations of yellow-bellied marmots (Marmota flaviventris) were lowest in May after emergence from hibernation and peaked in August prior to immergence. 2. Total corticosteroids were affected by age but not by sex or reproductive status. 3. There was no consistent relationship between measures of population density and concentrations of corticosteroids; when a significant relationship occurred, only 22-34% of the variation was explained. 4. Social status and social behavior were the major factors affecting corticosteroid concentrations.

  20. Factors affecting Iran`s future. Final report

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

    Sinai, J.

    1993-05-28

    This study examines the factors affecting Iran`s future by focusing on the demographic, economic, and military trends in Iran and their impact on the country`s national security objectives in the next decade. The paper also assesses the implications of an economic embargo on Iran and potential Iranian threats to regional and United States national interests.

  1. Are Affective Factors a Good Predictor of Science Achievement? Examining the Role of Affective Factors Based on PISA 2006

    ERIC Educational Resources Information Center

    Ozel, Murat; Caglak, Serdar; Erdogan, Mehmet

    2013-01-01

    This study investigated how affective factors like attitude and motivation contribute to science achievement in PISA 2006 using linear structural modeling. The data set of PISA 2006 collected from 4942 fifteen-year-old Turkish students (2290 females, 2652 males) was used for the statistical analyses. A total of 42 selected items on a four point…

  2. Effects of double and triple bonds on the spatial representations of odorants in the rat olfactory bulb.

    PubMed

    Johnson, Brett A; Ong, Joan; Lee, Kaman; Ho, Sabrina L; Arguello, Spart; Leon, Michael

    2007-02-01

    Many naturally occurring volatile chemicals that are detected through the sense of smell contain unsaturated (double or triple) carbon-carbon bonds. These bonds can affect odors perceived by humans, yet in a prior study of unsaturated hydrocarbons we found only very minor effects of unsaturated bonds. In the present study, we tested the possibility that unsaturated bonds affect the recognition of oxygen-containing functional groups, because humans perceive odor differences between such molecules. We therefore compared spatial activity patterns across the entire glomerular layer of the rat olfactory bulb evoked by oxygen-containing odorants differing systematically in the presence, position, number, and stereochemistry of unsaturated bonds. We quantified activity patterns by mapping [(14)C]2-deoxyglucose uptake into anatomically standardized data matrices, which we compared statistically. We found that the presence and number of unsaturated bonds consistently affected activity patterns, with the largest effect related to the presence of a triple bond. Effects of bond saturation included a loss of activity in glomeruli strongly activated by the corresponding saturated odorants and/or the presence of activity in areas not stimulated by the corresponding saturated compounds. The position of double bonds also affected patterns of activity, but cis vs. trans configuration had no measurable impact in all five sets of stereoisomers that we studied. These results simultaneously indicate the importance of interactions between carbon-carbon bond types and functional groups in the neural coding of odorant chemical information and highlight the emerging concept that the rat olfactory system is more sensitive to certain types of chemical differences than others. (c) 2006 Wiley-Liss, Inc.

  3. Determinants of Interest Rates on Corporate Bonds of Mining Enterprises

    NASA Astrophysics Data System (ADS)

    Ranosz, Robert

    2017-09-01

    This article is devoted to the determinants of interest rates on corporate bonds of mining enterprises. The study includes a comparison between the cost of foreign capital as resulting from the issue of debt instruments in different sectors of the economy in relation to the mining industry. The article also depicts the correlation between the rating scores published by the three largest rating agencies: S&P, Moody's, and Fitch. The test was based on simple statistical methods. The analysis performed indicated that there is a dependency between the factors listed and the amount of interest rates on corporate bonds of global mining enterprises. Most significant factors include the rating level and the period for which the given series of bonds was issued. Additionally, it is not without significance whether the given bond has additional options. Pursuant to the obtained results, is should be recognized that in order to reduce the interest rate on bonds, mining enterprises should pay particular attention to the rating and attempt to include additional options in issued bonds. Such additional options may comprise, for example, an ability to exchange bonds to shares or raw materials.

  4. Factors affecting cardiac rehabilitation referral by physician specialty.

    PubMed

    Grace, Sherry L; Grewal, Keerat; Stewart, Donna E

    2008-01-01

    Cardiac rehabilitation (CR) is widely underutilized because of multiple factors including physician referral practices. Previous research has shown CR referral varies by type of provider, with cardiologists more likely to refer than primary care physicians. The objective of this study was to compare factors affecting CR referral in primary care physicians versus cardiac specialists. A cross-sectional survey of a stratified random sample of 510 primary care physicians and cardiac specialists (cardiologists or cardiovascular surgeons) in Ontario identified through the Canadian Medical Directory Online was administered. One hundred four primary care physicians and 81 cardiac specialists responded to the 26-item investigator-generated survey examining medical, demographic, attitudinal, and health system factors affecting CR referral. Primary care physicians were more likely to endorse lack of familiarity with CR site locations (P < .001), lack of standardized referral forms (P < .001), inconvenience (P = .04), program quality (P = .004), and lack of discharge communication from CR (P = .001) as factors negatively impacting CR referral practices than cardiac specialists. Cardiac specialists were significantly more likely to perceive that their colleagues and department would regularly refer patients to CR than primary care physicians (P < .001). Where differences emerged, primary care physicians were more likely to perceive factors that would impede CR referral, some of which are modifiable. Marketing CR site locations, provision of standardized referral forms, and ensuring discharge summaries are communicated to primary care physicians may improve their willingness to refer to CR.

  5. Human-animal bonds between zoo professionals and the animals in their care.

    PubMed

    Hosey, Geoff; Melfi, Vicky

    2012-01-01

    Some human-animal relationships can be so positive that they confer emotional well-being to both partners and can thus be viewed as bonds. In this study, 130 delegates at zoo research and training events completed questionnaires in which they were asked about their professional work in the zoo and whether they believed they had established bonds with any animals. They were also asked to indicate agreement or disagreement with several statements about human-animal bonds. Results showed that many zoo professionals consider that they have established bonds with some of their animals; 103 respondents believed that they had a bond with at least one animal, and 78 of these identified that the bond was with a zoo animal. The most frequent bonds reported were with primates (n = 24) and carnivores (n = 28). Perceived benefits of these bonds to the respondents included both operational (animal easier to handle, easier to administer treatments to) and affective (sense of well-being, enjoyment at being with the animal). Identifying benefits to the animals was more difficult. Most respondents identified similar benefits for their animals as for themselves, i.e. operational (animal responded more calmly, appeared less stressed) and affective (animal appeared to enjoy contact with respondent, seemed more content). This suggests that bonding between zoo professionals and their animals could have profound consequences for the management and welfare of the animals, not to mention the job satisfaction of the people involved. © 2010 Wiley Periodicals, Inc.

  6. Effect of layered manufacturing techniques, alloy powders, and layer thickness on metal-ceramic bond strength.

    PubMed

    Ekren, Orhun; Ozkomur, Ahmet; Ucar, Yurdanur

    2018-03-01

    Direct metal laser sintering (DMLS) and direct metal laser melting (DMLM) have become popular for fabricating the metal frameworks of metal-ceramic restorations. How the type of layered manufacturing device, layer thickness, and alloy powder may affect the bond strength of ceramic to metal substructure is unclear. The purpose of this in vitro study was to evaluate the bond strength of dental porcelain to metal frameworks fabricated using different layered manufacturing techniques (DMLS and DMLM), Co-Cr alloy powders, and layer thicknesses and to evaluate whether a correlation exists between the bond strength and the number of ceramic remnants on the metal surface. A total of 75 bar-shaped metal specimens (n=15) were fabricated using either DMLS or DMLM. The powder alloys used were Keramit NP-S and EOS-Cobalt-Chrome SP-2 with layer thicknesses of 20 μm and 30 μm. After ceramic application, the metal-ceramic bond strength was evaluated with a 3-point-bend test. Three-way ANOVA followed by the Tukey honest significance difference test were used for statistical analysis (α=.05). De-bonding surface microstructure was observed with scanning electron microscopy. Energy dispersive spectroscopy analysis was conducted to evaluate the correlation between ceramic remnants on the metal surface and bond strength values. The mean bond strength value of DMLS was significantly higher than that of DMLM. While no statistically significant difference was found between layer thicknesses, alloy powders closely affected bond strength. Statistical comparisons revealed that the highest bond strength could be achieved with DMLS-Cobalt-Chrome SP2-20μm, and the lowest bond strength was observed in DMLS-Keramit NP-S-20μm (P≤.05). No correlation was found between porcelain remnants on the metal surface and bond strength values. The layered manufacturing device and the alloy powders evaluated in the current study closely affected the bond strength of dental porcelain to a metal framework

  7. The Japanese version of the Postpartum Bonding Questionnaire: Examination of the reliability, validity, and scale structure.

    PubMed

    Suetsugu, Yoshiko; Honjo, Shuji; Ikeda, Mari; Kamibeppu, Kiyoko

    2015-07-01

    The purpose of this study was to develop the Japanese version of the Postpartum Bonding Questionnaire (PBQ) to gather data on Japanese mothers for comparison with other cultures and to examine the scale structure of the PBQ among Japanese mothers. We administered the PBQ to a cross-section of 244 mothers 4 weeks after delivery and again 2 weeks later to 199 mothers as a retest to examine reliability. We used exploratory factor analysis to evaluate the factor structure of the PBQ. Correlations with the Mother-to-Infant Bonding Scale (MIBS), the Maternal Attachment Inventory (MAI), Edinburgh Postnatal Depression Scale (EPDS), and sociodemographic variables were calculated for validation. The 14-item version of the PBQ extracted by exploratory analysis consisted of four factors: 'impaired bonding', 'rejection and anger', 'anxiety about care', and 'lack of affection'. We found significant correlations of the total scores of the PBQ and the 14-item version of the PBQ positively with the MIBS and negatively with the MAI. Moderate significant correlations with total scores were also found with the EPDS. Total scores for primiparous and depressed mothers were higher than those for multiparous mothers and mothers without depression. The results of this study demonstrated the reliability and validity of the PBQ and the 14-item version of the PBQ in Japanese mothers 4 weeks after delivery. Copyright © 2015. Published by Elsevier Inc.

  8. Effect of Delayed Bonding and Antioxidant Application on the Bond Strength to Enamel after Internal Bleaching.

    PubMed

    Kılınç, Halil İbrahim; Aslan, Tuğrul; Kılıç, Kerem; Er, Özgür; Kurt, Gökmen

    2016-07-01

    This study evaluated the effect of delayed bonding and antioxidant application (AA, 10% sodium ascorbate) after internal bleaching (35% carbamide peroxide) on the shear bond strength of an adhesive cement to enamel. Eighty-four human maxillary central incisors were endodontically treated. The control group remained unbleached with no AA. Experimental groups were all internally bleached. The buccal enamel was finished and polished with metallographic paper to a refinement of #600, in order to obtain a 5-mm(2) flat bonding area. An adhesive cement (Clearfil Esthetic) was placed into a plastic tube with internal diameter of 3 mm and a 3-mm height and cured on the enamel. Bonding occurred either immediately after bleaching (group Im), a 7-day delay (group 7), or a 14-day delay (group 14), and half the specimens were treated with antioxidant application (groups Im-AA, 7-AA, and 14-AA). Shear bond strength testing was performed on a universal testing machine, and data were analyzed with ANOVA and Fisher test (5%). Delaying of bonding is a useful factor for enhancing shear bond strength (p < 0.05), whereas AA only enhanced shear bond strength after 7 days delayed bleaching (p < 0.05). The highest bond strength was noted in groups 7-AA (20.51 ± 4.5 MPa), 14 (19.82 ± 4.6), 14-AA (20.27 ± 4.4), and control (20.51 ± 5.1), which were not significantly different from each other. After internal bleaching, adhesive cementation to enamel is recommended only when delayed 14 days, or delayed 7 days with sodium ascorbate application. © 2015 by the American College of Prosthodontists.

  9. Factors Affecting Radiologist's PACS Usage.

    PubMed

    Forsberg, Daniel; Rosipko, Beverly; Sunshine, Jeffrey L

    2016-12-01

    The purpose of this study was to determine if any of the factors radiologist, examination category, time of week, and week effect PACS usage, with PACS usage defined as the sequential order of computer commands issued by a radiologist in a PACS during interpretation and dictation. We initially hypothesized that only radiologist and examination category would have significant effects on PACS usage. Command logs covering 8 weeks of PACS usage were analyzed. For each command trace (describing performed activities of an attending radiologist interpreting a single examination), the PACS usage variables number of commands, number of command classes, bigram repetitiveness, and time to read were extracted. Generalized linear models were used to determine the significance of the factors on the PACS usage variables. The statistical results confirmed the initial hypothesis that radiologist and examination category affect PACS usage and that the factors week and time of week to a large extent have no significant effect. As such, this work provides direction for continued efforts to analyze system data to better understand PACS utilization, which in turn can provide input to enable optimal utilization and configuration of corresponding systems. These continued efforts were, in this work, exemplified by a more detailed analysis using PACS usage profiles, which revealed insights directly applicable to improve PACS utilization through modified system configuration.

  10. Emotional intelligence, attachment and bonding and communication.

    PubMed

    Gunning, Melanie D; Waugh, Harriet; Robertson, Fiona; Holmes, Bjarne

    2011-03-01

    This study explores the use of emotional intelligence (El) as an explanatory factor in the relationship between attachment and mother-infant bonding and communication. With the long-term aim of synthesising these constructs into a useful tool to identify risk for mother-infant bonding and communication problems, the study utilised previously validated questionnaires. The inter-relationships between El and adult attachment anxiety/avoidance were investigated alongside their associations with mothers' self-assessments of bonding problems and with observer-based assessments of maternal communicative behaviour. The study suggests that the El capacity for managing and controlling emotions in challenging situations mediates the link between anxious attachment style and bonding problems. Women with lower El also showed more disrupted behaviours during play with their infants. The results support further development of the use of the constructs of El and attachment in identifying risk for bonding and communication difficulties.

  11. Cognitive Factors Affecting Freeze-like Behavior in Humans.

    PubMed

    Alban, Michael W; Pocknell, Victoria

    2017-01-01

    Contemporary research on survival-related defensive behaviors has identified physiological markers of freeze/flight/fight. Our research focused on cognitive factors associated with freeze-like behavior in humans. Study 1 tested if an explicit decision to freeze is associated with the psychophysiological state of freezing. Heart rate deceleration occurred when participants chose to freeze. Study 2 varied the efficacy of freezing relative to other defense options and found "freeze" was responsive to variations in the perceived effectiveness of alternative actions. Study 3 tested if individual differences in motivational orientation affect preference for a "freeze" option when the efficacy of options is held constant. A trend in the predicted direction suggested that naturally occurring cognitions led loss-avoiders to select "freeze" more often than reward-seekers. In combination, our attention to the cognitive factors affecting freeze-like behavior in humans represents a preliminary step in addressing an important but neglected research area.

  12. Factors affecting the use of hardwood flooring in urban rehabilitation

    Treesearch

    Robert L. Jr. Nevel; Robert L. Jr. Nevel

    1973-01-01

    The continued use of hardwood flooring in urban rehabilitation is being threatened. A study of the influences that determine the choice of flooring indicates that economic, physical, or technological factors dominate. Most factors affecting the use of hardwood flooring are related to cost, availability, and compatibility. Of these factors, time and cost of installation...

  13. Financial and operational ratios for bond-insured hospitals.

    PubMed

    McCue, Michael J; McCluer, R Forrest

    2008-01-01

    Few, if any, researchers have analyzed the performance indicators of companies that offer bond insurance to hospitals and healthcare systems. The authors of this study analyzed the key financial and operational indicators of independent hospitals and hospitals within large multihospital systems that are insured by the 5 major bond insurance companies. The authors examined 87 insured bond issues; the results of this study show that some insurers cover healthcare facilities that have strong operational traits and others focus on financial factors.

  14. Estimation of Hydrogen-Exchange Protection Factors from MD Simulation Based on Amide Hydrogen Bonding Analysis.

    PubMed

    Park, In-Hee; Venable, John D; Steckler, Caitlin; Cellitti, Susan E; Lesley, Scott A; Spraggon, Glen; Brock, Ansgar

    2015-09-28

    Hydrogen exchange (HX) studies have provided critical insight into our understanding of protein folding, structure, and dynamics. More recently, hydrogen exchange mass spectrometry (HX-MS) has become a widely applicable tool for HX studies. The interpretation of the wealth of data generated by HX-MS experiments as well as other HX methods would greatly benefit from the availability of exchange predictions derived from structures or models for comparison with experiment. Most reported computational HX modeling studies have employed solvent-accessible-surface-area based metrics in attempts to interpret HX data on the basis of structures or models. In this study, a computational HX-MS prediction method based on classification of the amide hydrogen bonding modes mimicking the local unfolding model is demonstrated. Analysis of the NH bonding configurations from molecular dynamics (MD) simulation snapshots is used to determine partitioning over bonded and nonbonded NH states and is directly mapped into a protection factor (PF) using a logistics growth function. Predicted PFs are then used for calculating deuteration values of peptides and compared with experimental data. Hydrogen exchange MS data for fatty acid synthase thioesterase (FAS-TE) collected for a range of pHs and temperatures was used for detailed evaluation of the approach. High correlation between prediction and experiment for observable fragment peptides is observed in the FAS-TE and additional benchmarking systems that included various apo/holo proteins for which literature data were available. In addition, it is shown that HX modeling can improve experimental resolution through decomposition of in-exchange curves into rate classes, which correlate with prediction from MD. Successful rate class decompositions provide further evidence that the presented approach captures the underlying physical processes correctly at the single residue level. This assessment is further strengthened in a comparison of

  15. Factors Affecting Sleep Quality of Patients in Intensive Care Unit

    PubMed Central

    Bihari, Shailesh; Doug McEvoy, R.; Matheson, Elisha; Kim, Susan; Woodman, Richard J.; Bersten, Andrew D.

    2012-01-01

    Introduction: Sleep disturbance is a frequently overlooked complication of intensive care unit (ICU) stay. Aim: To evaluate sleep quality among patients admitted to ICU and investigate environmental and non-environmental factors that affect sleep quality in ICU. Methods: Over a 22-month period, we consecutively recruited patients who spent ≥ 2 nights post-endotracheal extubation in ICU and who were orientated to time, place, and person on the day of discharge. Self-reported sleep quality, according to a modified Freedman questionnaire, which provided data on self-reported ICU sleep quality in ICU and environmental factors affecting sleep quality in the ICU, were collected. We also investigated non-environmental factors, such as severity of illness, ICU interventions, and medications that can affect sleep quality. Results: Fifty males and 50 females were recruited with a mean (± SD) age of 65.1 ± 15.2 years. APACHE II score at admission to ICU was 18.1 ± 7.5 with duration of stay 6.7 ± 6.5days. Self-reported sleep quality score at home (1 = worst; 10 = best) was 7.0 ± 2.2; this decreased to 4.0 ± 1.7 during their stay in ICU (p < 0.001). In multivariate analysis with APACHE III as severity of illness (R2 = 0.25), factors [exp(b)(95% CI), p value] which significantly affected sleep in ICU were sex [0.37(0.19-0.72), p < 0.01], age and sex interaction [1.02(1.01-1.03), p < 0.01], bedside phone [0.92(0.87-0.97), p < 0.01], prior quality of sleep at home [1.30(1.05-1.62), p = 0.02], and use of steroids [0.82(0.69-0.98), p = 0.03] during the stay in ICU. Conclusion: Reduced sleep quality is a common problem in ICU with a multifactorial etiology. Citation: Bihari S; McEvoy RD; Kim S; Woodman RJ; Bersten AD. Factors affecting sleep quality of patients in intensive care unit. J Clin Sleep Med 2012;8(3):301-307. PMID:22701388

  16. An Analysis of Factors That Affect the Educational Performance of Agricultural Students

    ERIC Educational Resources Information Center

    Greenway, Gina

    2012-01-01

    Many factors contribute to student achievement. This study focuses on three areas: how students learn, how student personality type affects performance, and how course format affects performance outcomes. The analysis sought to improve understanding of the direction and magnitude with which each of these factors impacts student success. Improved…

  17. Assessment of Factor Affecting Institutional Performance: The Case of Wolaita Sodo University

    ERIC Educational Resources Information Center

    Shibru, Sintayehu; Bibiso, Mesfin; Ousman, Kedir

    2017-01-01

    The purpose of this study is to explore factors that affect institutional performance of Wolaita Sodo University. The study has identified middle level manager's perceptions toward institutional performance to indicate the key factors that seem to affect the performance of the university. Data were collected using structured questionnaires and…

  18. 48 CFR 1228.106-1 - Bonds and bond-related forms.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... GENERAL CONTRACTING REQUIREMENTS BONDS AND INSURANCE Bonds and Other Financial Protections 1228.106-1 Bonds and bond-related forms. (b) Standard Form (SF) 25, Performance Bond, prescribed at (FAR) 48 CFR 28...) shall not be used by contractors when a performance bond is required. ...

  19. H-Bond Self-Assembly: Folding versus Duplex Formation.

    PubMed

    Núñez-Villanueva, Diego; Iadevaia, Giulia; Stross, Alexander E; Jinks, Michael A; Swain, Jonathan A; Hunter, Christopher A

    2017-05-17

    Linear oligomers equipped with complementary H-bond donor (D) and acceptor (A) sites can interact via intermolecular H-bonds to form duplexes or fold via intramolecular H-bonds. These competing equilibria have been quantified using NMR titration and dilution experiments for seven systems featuring different recognition sites and backbones. For all seven architectures, duplex formation is observed for homo-sequence 2-mers (AA·DD) where there are no competing folding equilibria. The corresponding hetero-sequence AD 2-mers also form duplexes, but the observed self-association constants are strongly affected by folding equilibria in the monomeric states. When the backbone is flexible (five or more rotatable bonds separating the recognition sites), intramolecular H-bonding is favored, and the folded state is highly populated. For these systems, the stability of the AD·AD duplex is 1-2 orders of magnitude lower than that of the corresponding AA·DD duplex. However, for three architectures which have more rigid backbones (fewer than five rotatable bonds), intramolecular interactions are not observed, and folding does not compete with duplex formation. These systems are promising candidates for the development of longer, mixed-sequence synthetic information molecules that show sequence-selective duplex formation.

  20. Factors affecting onset of puberty in Denizli province in Turkey.

    PubMed

    Semiz, Serap; Kurt, Funda; Kurt, Devrim Tanil; Zencir, Mehmet; Sevinç, Ozgür

    2009-01-01

    The relationship between the possible factors affecting pubertal onset and pubertal timing was investigated in the Denizli province in Turkey. A total number of 3311 subjects (1562 girls, 1749 boys) aged 6-16.5 years participated in this study. Body mass index (BMI) was calculated. Pubertal stages were assessed according to methods of Marshall and Tanner. Testicular volume was determined using Prader orchidometer. Menarcheal age was recorded. All parents and students completed different questionnaires on demographic variables affecting pubertal timing such as socioeconomic conditions, psychosocial factors, exercise, nutritional status, chronic diseases, migration and birth weight. Using distribution percentiles of pubertal stages according to age, the relation between pubertal timing and factors affecting puberty was investigated. There was no significant association between exercise, birth weight, migration, chronic disease, and socioeconomic status and age of puberty onset. Menarcheal age of overweight and obese girls was significantly lower than that of girls with normal weight. In-family stress was the cause of early puberty in girls and of delayed puberty in boys.

  1. Factors affecting the periapical healing process of endodontically treated teeth.

    PubMed

    Holland, Roberto; Gomes, João Eduardo; Cintra, Luciano Tavares Angelo; Queiroz, Índia Olinta de Azevedo; Estrela, Carlos

    2017-01-01

    Tissue repair is an essential process that reestablishes tissue integrity and regular function. Nevertheless, different therapeutic factors and clinical conditions may interfere in this process of periapical healing. This review aims to discuss the important therapeutic factors associated with the clinical protocol used during root canal treatment and to highlight the systemic conditions associated with the periapical healing process of endodontically treated teeth. The antibacterial strategies indicated in the conventional treatment of an inflamed and infected pulp and the modulation of the host's immune response may assist in tissue repair, if wound healing has been hindered by infection. Systemic conditions, such as diabetes mellitus and hypertension, can also inhibit wound healing. The success of root canal treatment is affected by the correct choice of clinical protocol. These factors are dependent on the sanitization process (instrumentation, irrigant solution, irrigating strategies, and intracanal dressing), the apical limit of the root canal preparation and obturation, and the quality of the sealer. The challenges affecting the healing process of endodontically treated teeth include control of the inflammation of pulp or infectious processes and simultaneous neutralization of unpredictable provocations to the periapical tissue. Along with these factors, one must understand the local and general clinical conditions (systemic health of the patient) that affect the outcome of root canal treatment prediction.

  2. Nurse aide decision making in nursing homes: factors affecting empowerment.

    PubMed

    Chaudhuri, Tanni; Yeatts, Dale E; Cready, Cynthia M

    2013-09-01

    To evaluate factors affecting structural empowerment among nurse aides in nursing homes. Structural empowerment can be defined as the actual rather than perceived ability to make autonomous decisions within an organisation. Given the paucity of research on the subject, this study helps to close the gap by identifying factors that affect nurse aide empowerment, that is, decision-making among nurse aides. The data for the study come from self-administered questionnaires distributed to direct-care workers (nurse aides) in 11 nursing homes in a southern state in the USA. Ordinary least square regression models were estimated to analyse the effects of demographic predictors, personal factors (competency, emotional exhaustion and positive attitude) and structural characteristics (coworker and supervisor support, information availability and shared governance) on nurse aide decision-making. Findings suggest race among demographic predictors, emotional exhaustion among personal characteristics, and supervisor support, and shared governance among structural factors, significantly affect nurse aide decision-making. It is important to explore race as one of the central determinants of structural empowerment among nurse aides. In addition, the nature and type of emotional exhaustion that propels decision-making needs to be further examined. The study shows the importance of shared governance and supervisor support for fostering nurse aide empowerment. © 2013 Blackwell Publishing Ltd.

  3. Pauling bond strength, bond length and electron density distribution

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

    Gibbs, Gerald V.; Ross, Nancy L.; Cox, David F.

    2014-01-18

    A power law regression equation, = 1.46(/r)-0.19, connecting the average experimental bond lengths, , with the average accumulation of the electron density at the bond critical point, , between bonded metal M and oxygen atoms, determined at ambient conditions for oxide crystals, where r is the row number of the M atom, is similar to the regression equation R(M-O) = 1.39(ρ(rc)/r)-0.21 determined for three perovskite crystals for pressures as high as 80 GPa. The two equations are also comparable with those, = 1.43( /r)-0.21, determined for a large number of oxide crystals at ambient conditions and = 1.39(/r)-0.22, determined formore » geometry optimized hydroxyacid molecules, that connect the bond lengths to the average Pauling electrostatic bond strength, , for the M-O bonded interactions. On the basis of the correspondence between the two sets of equations connecting ρ(rc) and the Pauling bond strength s with bond length, it appears that Pauling’s simple definition of bond strength closely mimics the accumulation of the electron density between bonded pairs of atoms. The similarity of the expressions for the crystals and molecules is compelling evidence that the M-O bonded interactions for the crystals and molecules 2 containing the same bonded interactions are comparable. Similar expressions, connecting bond lengths and bond strength, have also been found to hold for fluoride, nitride and sulfide molecules and crystals. The Brown-Shannon bond valence, σ, power law expression σ = [R1/(R(M-O)]N that has found wide use in crystal chemistry, is shown to be connected to a more universal expression determined for oxides and the perovskites, = r[(1.41)/]4.76, demonstrating that the bond valence for a bonded interaction is likewise closely connected to the accumulation of the electron density between the bonded atoms. Unlike the Brown-Shannon expression, it is universal in that it holds for the M-O bonded interactions for a relatively wide range of M atoms of the

  4. Nutritional Factors Affecting Adult Neurogenesis and Cognitive Function

    USDA-ARS?s Scientific Manuscript database

    Adult neurogenesis, a complex process by which stem cells in the hippocampal brain region differentiate and proliferate into new neurons and other resident brain cells, is known to be affected by many intrinsic and extrinsic factors, including diet. Neurogenesis plays a critical role in neural plas...

  5. Push-out bond strengths of two fiber post types bonded with different dentin bonding agents.

    PubMed

    Topcu, Fulya Toksoy; Erdemir, Ugur; Sahinkesen, Gunes; Mumcu, Emre; Yildiz, Esra; Uslan, Ibrahim

    2010-05-01

    The aim of this study was to evaluate the regional push-out bond strengths for two fiber-reinforced post types using three different dentin bonding agents. Sixty single-rooted extracted human first premolar teeth were sectioned below the cemento-enamel junction, and the roots were endodontically treated. Following standardized post space preparations, the roots were divided into two fiber-post groups (Glassix and Carbopost), and further divided into three subgroups of 10 specimens each for the bonding systems self-etching dentin bonding agents (Clearfil SE Bond and Optibond all-in-one), and total-etching dentin bonding agent (XP Bond). A dual-cure resin luting cement (Maxcem) was then placed in the post spaces and posts were then seated into the root canals polymerized through the cervical portion. The roots were then cut into 3-mm thick sections. Push-out tests were performed at a crosshead speed of 0.5 mm/min. The data were analyzed with multivariate ANOVA (alpha = 0.05). The morphology of interface between different dentin bonding agents from the cervical sections were analyzed with SEM. Glass fiber-reinforced posts demonstrated significantly higher push-out bond strengths than carbon fiber-reinforced posts (p < 0.001). Bond strength values decreased significantly from the cervical to the apical root canal regions (p < 0.001). Self-etching dentin adhesive Clearfil SE Bond and total-etching dentin adhesive XP Bond demonstrated similar bond strengths values and this was significantly higher compared with the Optibond all-in-one in cervical root canal region. In conclusion, in all root segments, the glass fiber-reinforced posts provided significantly increased post retention than the carbon fiber-reinforced posts, regardless of the adhesive used. (c) 2010 Wiley Periodicals, Inc.

  6. Halogen bonding (X-bonding): A biological perspective

    PubMed Central

    Scholfield, Matthew R; Zanden, Crystal M Vander; Carter, Megan; Ho, P Shing

    2013-01-01

    The concept of the halogen bond (or X-bond) has become recognized as contributing significantly to the specificity in recognition of a large class of halogenated compounds. The interaction is most easily understood as primarily an electrostatically driven molecular interaction, where an electropositive crown, or σ-hole, serves as a Lewis acid to attract a variety of electron-rich Lewis bases, in analogous fashion to a classic hydrogen bonding (H-bond) interaction. We present here a broad overview of X-bonds from the perspective of a biologist who may not be familiar with this recently rediscovered class of interactions and, consequently, may be interested in how they can be applied as a highly directional and specific component of the molecular toolbox. This overview includes a discussion for where X-bonds are found in biomolecular structures, and how their structure–energy relationships are studied experimentally and modeled computationally. In total, our understanding of these basic concepts will allow X-bonds to be incorporated into strategies for the rational design of new halogenated inhibitors against biomolecular targets or toward molecular engineering of new biological-based materials. PMID:23225628

  7. Continuous feelings of love? The parental bond from pregnancy to toddlerhood.

    PubMed

    de Cock, Evi S A; Henrichs, Jens; Vreeswijk, Charlotte M J M; Maas, A Janneke B M; Rijk, Catharina H A M; van Bakel, Hedwig J A

    2016-02-01

    Both prenatal and postnatal parental bonding (i.e., the affective tie from parent to child) have important effects on parental and child functioning. However, research on the continuity and correlates of parental bonding is lacking. Therefore, the goal of the present study was to examine the stability of bonding levels and to explore distinct bonding patterns with a latent class analysis. Moreover, the correlates of these bonding patterns in the parental-, child-, and contextual domain were studied. Levels of maternal (N = 370) and paternal (N = 292) bonding and potential correlates were assessed at 26 weeks of pregnancy, 6 months, and 24 months postpartum. Results showed moderate stability of bonding from pregnancy to toddlerhood. For both mothers and fathers, 4 distinct bonding patterns were found. Parents with low bonding patterns were characterized by increased anxiety and parenting stress, less partner support, less adaptive personality profiles, and children with difficult temperament. These findings indicate the importance of monitoring young children's parents with poor levels of bonding as their bonding patterns remain stable from pregnancy until toddlerhood and because those parents experience problems in multiple domains. (c) 2016 APA, all rights reserved).

  8. Selective Acid Etching Improves the Bond Strength of Universal Adhesive to Sound and Demineralized Enamel of Primary Teeth.

    PubMed

    Antoniazzi, Bruna Feltrin; Nicoloso, Gabriel Ferreira; Lenzi, Tathiane Larissa; Soares, Fabio Zovico Maxnuck; Rocha, Rachel de Oliveira

    To evaluate the influence of enamel condition and etching strategy on bond strength of a universal adhesive in primary teeth. Thirty-six primary molars were randomly assigned to six groups (n = 6) according to the enamel condition (sound [S] and demineralized [DEM]/cariogenic challenge by pH cycling prior to restorative procedures) and adhesive system (Scotchbond Universal Adhesive [SBU]) used in either etch-and-rinse (ER) or selfetching (SE) mode, with Clearfil SE Bond as the self-etching control. The adhesives were applied to flat enamel surfaces and composite cylinders (0.72 mm2) were built up. After 24-h storage in water, specimens were subjected to the microshear test. Bond strength (MPa) data were analyzed using two-way ANOVA and Tukey's post-hoc tests (α = 0.05). Significant differences were found considering the factors adhesive system (p = 0.003) and enamel condition (p = 0.001). Demineralized enamel negatively affected the bond strength, with μSBS values approximately 50% lower than those obtained for sound enamel. SBU performed better in etch-and-rinse mode, and the bond strength found for SBU applied in self-etching mode was similar to that of CSE. Enamel etching with phosphoric acid improves the bond strength of a universal adhesive system to primary enamel. Demineralized primary enamel results in lower bond strength.

  9. The key factors affecting students' individual interest in school science lessons

    NASA Astrophysics Data System (ADS)

    Cheung, Derek

    2018-01-01

    Individual interest in school science lessons can be defined as a relatively stable and enduring personal emotion comprising affective and behavioural reactions to events in the regular science lessons at school. Little research has compared the importance of different factors affecting students' individual interest in school science lessons. The present study aimed to address this gap, using a mixed methods design. Qualitative interview data were collected from 60 Hong Kong junior secondary school students, who were asked to describe the nature of their interest in science lessons and the factors to which they attribute this. Teacher interviews, parent interviews, and classroom observations were conducted to triangulate student interview data. Five factors affecting students' individual interest in school science lessons were identified: situational influences in science lessons, individual interest in science, science self-concept, grade level, and gender. Quantitative data were then collected from 591 students using a questionnaire. Structural equation modelling was applied to test a hypothesised model, which provided an acceptable fit to the student data. The strongest factor affecting students' individual interest in school science lessons was science self-concept, followed by individual interest in science and situational influences in science lessons. Grade level and gender were found to be nonsignificant factors. These findings suggest that teachers should pay special attention to the association between academic self-concept and interest if they want to motivate students to learn science at school.

  10. The effect of air thinning on dentin adhesive bond strength.

    PubMed

    Hilton, T J; Schwartz, R S

    1995-01-01

    The purpose of this study was to determine if air thinning three dentin adhesives would affect bond strength to dentin. Ninety human molars were mounted in acrylic and the occlusal surfaces ground to expose a flat dentin surface. Thirty teeth were randomly assigned to one of the following dentin bonding agent/composite combinations: A) Universal Bond 3/TPH (Caulk), B) All-Bond 2/Bis-Fil-P (Bisco), and C) Scotchbond Multi-Purpose/Z-100 (3m). The primers were applied following the manufacturers' instructions. The adhesives were applied by two methods. A thin layer of adhesive was applied with a brush to 15 specimens in each group and light cured. Adhesive was brushed on to the remaining 15 teeth in the group, air thinned for 3 seconds, and then polymerized. The appropriate composite was applied in 2 mm increments and light cured utilizing a 5 mm-in-diameter split Teflon mold. Following 3 months of water storage, all groups were shear tested to failure on an Instron Universal Testing Machine. Bond strength was significantly higher in all groups when the dentin bonding agent was painted on without being air thinned. Scotchbond Multi-Purpose had significantly higher bond strength than All-Bond 2, which had significantly higher bond strength than Universal Bond 3.

  11. Effect of acid and laser etching on shear bond strength of conventional and resin-modified glass-ionomer cements to composite resin.

    PubMed

    Navimipour, Elmira Jafari; Oskoee, Siavash Savadi; Oskoee, Parnian Alizadeh; Bahari, Mahmoud; Rikhtegaran, Sahand; Ghojazadeh, Morteza

    2012-03-01

    Success in sandwich technique procedures can be achieved through an acceptable bond between the materials. The aim of this study was to compare the effect of 35% phosphoric acid and Er,Cr:YSGG laser on shear bond strength of conventional glass-ionomer cement (GIC) and resin-modified glass-ionomer cement (RMGIC) to composite resin in sandwich technique. Sixty-six specimens were prepared from each type of glass-ionomer cements and divided into three treatment groups as follows: without pretreatment, acid etching by 35% phosphoric acid for 15 s, and 1-W Er,Cr:YSGG laser treatment for 15 s with a 600-μm-diameter tip aligned perpendicular to the target area at a distance of 1 mm from the surface. Energy density of laser irradiation was 17.7 J/cm(2). Two specimens in each group were prepared for evaluation under a scanning electron microscope (SEM) after surface treatment and the remainder underwent bonding procedure with a bonding agent and composite resin. Then the shear bond strength was measured at a crosshead speed of 0.5 mm/min. Two-factor analysis of variance and post-hoc Tukey test showed that the cement type, surface treatment method, and the interaction of these two factors significantly affect the shear bond strength between glass-ionomer cements and composite resin (p < 0.05). Surface treatment with phosphoric acid or Er,Cr:YSGG laser increased the shear bond strength of GIC to composite resin; however, in RMGIC only laser etching resulted in significantly higher bond strength. These findings were supported by SEM results. The fracture mode was evaluated under a stereomicroscope at ×20.

  12. The Important Role of Halogen Bond in Substrate Selectivity of Enzymatic Catalysis

    NASA Astrophysics Data System (ADS)

    Jiang, Shuiqin; Zhang, Lujia; Cui, Dongbin; Yao, Zhiqiang; Gao, Bei; Lin, Jinping; Wei, Dongzhi

    2016-10-01

    The use of halogen bond is widespread in drug discovery, design, and clinical trials, but is overlooked in drug biosynthesis. Here, the role of halogen bond in the nitrilase-catalyzed synthesis of ortho-, meta-, and para-chlorophenylacetic acid was investigated. Different distributions of halogen bond induced changes of substrate binding conformation and affected substrate selectivity. By engineering the halogen interaction, the substrate selectivity of the enzyme changed, with the implication that halogen bond plays an important role in biosynthesis and should be used as an efficient and reliable tool in enzymatic drug synthesis.

  13. Enamel Wetness Effects on Microshear Bond Strength of Different Bonding Agents (Adhesive Systems): An in vitro Comparative Evaluation Study.

    PubMed

    Kulkarni, Girish; Mishra, Vinay K

    2016-05-01

    significant difference when compared with Clearfil SE Bond adhesive in dry enamel. Single Bond 2 adhesive showed no significant difference in microshear bond strength as compared with self-etching adhesive systems (Clearfil SE Bond and Xeno-V), when the enamel was kept wet. From the findings of the results, it was concluded that self-etching adhesives were not negatively affected by the presence of water on the enamel surface. The all-in-one adhesive showed different behavior depending on whether the enamel surface was dry or wet. So the enamel surface should not be desiccated, when self-etching adhesives are used.

  14. Stress intensity factors in bonded half planes containing inclined cracks and subjected to antiplane shear loading

    NASA Technical Reports Server (NTRS)

    Bassani, J. L.; Erdogan, F.

    1979-01-01

    The antiplane shear problem for two bonded dissimilar half planes containing a semi-infinite crack or two arbitrarily located collinear cracks is considered. For the semi-infinite crack the problem is solved for a concentrated wedge load and the stress intensity factor and the angular distribution of stresses are calculated. For finite cracks the problem is reduced to a pair of integral equations. Numerical results are obtained for cracks fully imbedded in a homogeneous medium, one crack tip touching the interface, and a crack crossing the interface for various crack angles.

  15. Stress intensity factors in bonded half planes containing inclined cracks and subjected to antiplane shear loading

    NASA Technical Reports Server (NTRS)

    Bassani, J. L.; Erdogan, F.

    1978-01-01

    The antiplane shear problem for two bonded dissimilar half planes containing a semi-infinite crack or two arbitrarily located collinear cracks was considered. For the semi-infinite crack the problem was solved for a concentrated wedge load and the stress intensity factor and the angular distribution of stresses were calculated. For finite cracks the problem was reduced to a pair of integral equations. Numerical results were obtained for cracks fully imbedded in a homogeneous medium, one crack tip touching the interface, and a crack crossing the interface for various crack angles.

  16. 75 FR 80114 - Agency Information Collection (Obligation To Report Factors Affecting Entitlement) Activity Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-21

    ... (Obligation To Report Factors Affecting Entitlement) Activity Under OMB Review AGENCY: Veterans Benefits... Report Factors Affecting Entitlement (38 CFR 3.204(a)(1), 38 CFR 3.256(a) and 38 CFR 3.277(b)). OMB... benefits must report changes in their entitlement factors. Individual factors such as income, marital...

  17. Factors Affecting Students' Grades in Principles of Economics

    ERIC Educational Resources Information Center

    Kara, Orhan; Bagheri, Fathollah; Tolin, Thomas

    2009-01-01

    Factors affecting students' grades in principles of microeconomics and macroeconomics students are analyzed from the data collected in two public universities. Results indicate that gender, number of hours worked, SAT scores, number of missed classes, recommending the course to a friend, instructors, being a junior, number of economics courses…

  18. Crack growth in bonded elastic half planes

    NASA Technical Reports Server (NTRS)

    Goree, J. G.

    1975-01-01

    Two solutions were developed for the two dimensional problem of bonded linearly elastic half-planes. For each solution, numerical results are presented for the stress intensity factors, strain energy release rate, stresses, and displacements. The behavior predicted by the studies was investigated experimentally using polymers for the material pairs. Close agreement was found for the critical stress intensity factor at fracture for the perpendicular crack near the interface. Fracture along the interface proved to be inconclusive due to difficulties in obtaining a brittle bond. Some interesting and predictable behavior regarding the potential for the crack to cross the interface was observed and is discussed.

  19. Systematic review of factors affecting pharmaceutical expenditures.

    PubMed

    Mousnad, Mohamed Awad; Shafie, Asrul Akmal; Ibrahim, Mohamed Izham

    2014-06-01

    To systematically identify the main factors contributing to the increase in pharmaceutical expenditures. A systematic search of published studies was conducted utilising major widely used electronic databases using the search terms 'factors,' 'financing,' 'pharmaceutical,' and 'expenditures.' To be included, the studies needed to: (1) measure at least one of the following outcomes: total growth in pharmaceutical expenditures, price growth or quantity growth; (2) mention a clear method for analysing the impact of factors affecting the increases in drug expenditures; (3) be written in English. Nonprimary articles that were published only as an abstract, a review, a commentary or a letter were excluded. From a total of 2039 studies, only 25 were included in the full review. The main determinant categories that were identified in the review were factors related to price, utilisation, therapeutic choice, demand and health care system. The major cost drivers were found to be changes in drug quantities and therapies as well as new drugs. It is important for policymakers to understand pharmaceutical spending trends and the factors that influence them in order to formulate effective cost containment strategies and design optimum drug policy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Pi Bond Orders and Bond Lengths

    ERIC Educational Resources Information Center

    Herndon, William C.; Parkanyi, Cyril

    1976-01-01

    Discusses three methods of correlating bond orders and bond lengths in unsaturated hydrocarbons: the Pauling theory, the Huckel molecular orbital technique, and self-consistent-field techniques. (MLH)

  1. Microshear bond strength of self-etching systems associated with a hydrophobic resin layer.

    PubMed

    De Vito Moraes, André Guaraci; Francci, Carlos; Carvalho, Ceci Nunes; Soares, Silvio Peixoto; Braga, Roberto Ruggiero

    2011-08-01

    To evaluate in vitro the microshear bond strength of adhesive systems applied to dentin according to manufacturers' instructions, associated or not with a hydrophobic layer of unfilled resin. Six self-etching adhesives (Clearfil SE Bond, Kuraray Medical; AdheSE, Ivoclar Vivadent; Xeno III, Dentsply; I Bond, Heraeus-Kulzer; Bond Force, Tokuyama; Futurabond DC, Voco) were tested. The labial dentin of sixty bovine incisors was exposed, and the teeth were divided into two groups according to the application or not of an extra hydrophobic resin layer (Scotchbond Multi Purpose Plus, bottle 3). Six composite cylinders (Filtek Z250, 3M ESPE) were built up on each treated surface. Specimens were stored in distilled water at 37ºC for 24 h and then subjected to the microshear bond strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. Microshear bond strength values were analyzed by 2-way ANOVA and Tukey's post-hoc test. Failure mode was determined using a stereomicroscope under 20X magnification. The application of the hydrophobic resin layer did not affect bond strength, except for AdheSE. However, the bond strengths with the hydrophobic layer were similar among the six tested systems (Clearfil: 17.1 ± 7.9; AdheSE: 14.5 ± 7.1; Xeno lll: 12.8 ± 7.7; I Bond: 9.5 ± 5.8; Bond Force: 17.5 ± 4.1; Futurabond: 7.7 ± 2.3). When used as recommended by the manufacturers, Bond Force presented statistically higher bond strength than AdheSE and I Bond (p < 0.05) (Clearfil 10.4 ± 4.9; AdheSE 1.6 ± 1.6; Xeno lll: 9.0 ± 3.8; I Bond: 3.0 ± 1.5; Bond Force: 14 ± 3.9; Futurabond: 8.8 ± 3.8). Failure mode was predominantly adhesive. The bond strength of the self-etching systems tested was not significantly affected by the application of a hydrophobic layer, but a significant improvement was observed in AdheSE.

  2. The ice-breaker effect: singing mediates fast social bonding.

    PubMed

    Pearce, Eiluned; Launay, Jacques; Dunbar, Robin I M

    2015-10-01

    It has been proposed that singing evolved to facilitate social cohesion. However, it remains unclear whether bonding arises out of properties intrinsic to singing or whether any social engagement can have a similar effect. Furthermore, previous research has used one-off singing sessions without exploring the emergence of social bonding over time. In this semi-naturalistic study, we followed newly formed singing and non-singing (crafts or creative writing) adult education classes over seven months. Participants rated their closeness to their group and their affect, and were given a proxy measure of endorphin release, before and after their class, at three timepoints (months 1, 3 and 7). We show that although singers and non-singers felt equally connected by timepoint 3, singers experienced much faster bonding: singers demonstrated a significantly greater increase in closeness at timepoint 1, but the more gradual increase shown by non-singers caught up over time. This represents the first evidence for an 'ice-breaker effect' of singing in promoting fast cohesion between unfamiliar individuals, which bypasses the need for personal knowledge of group members gained through prolonged interaction. We argue that singing may have evolved to quickly bond large human groups of relative strangers, potentially through encouraging willingness to coordinate by enhancing positive affect.

  3. The ice-breaker effect: singing mediates fast social bonding

    PubMed Central

    Pearce, Eiluned; Launay, Jacques; Dunbar, Robin I. M.

    2015-01-01

    It has been proposed that singing evolved to facilitate social cohesion. However, it remains unclear whether bonding arises out of properties intrinsic to singing or whether any social engagement can have a similar effect. Furthermore, previous research has used one-off singing sessions without exploring the emergence of social bonding over time. In this semi-naturalistic study, we followed newly formed singing and non-singing (crafts or creative writing) adult education classes over seven months. Participants rated their closeness to their group and their affect, and were given a proxy measure of endorphin release, before and after their class, at three timepoints (months 1, 3 and 7). We show that although singers and non-singers felt equally connected by timepoint 3, singers experienced much faster bonding: singers demonstrated a significantly greater increase in closeness at timepoint 1, but the more gradual increase shown by non-singers caught up over time. This represents the first evidence for an ‘ice-breaker effect’ of singing in promoting fast cohesion between unfamiliar individuals, which bypasses the need for personal knowledge of group members gained through prolonged interaction. We argue that singing may have evolved to quickly bond large human groups of relative strangers, potentially through encouraging willingness to coordinate by enhancing positive affect. PMID:26587241

  4. Key factors affecting dying children and their families.

    PubMed

    Hinds, Pamela S; Schum, Lisa; Baker, Justin N; Wolfe, Joanne

    2005-01-01

    The death of a child alters the life and health of others immediately and for the rest of their lives. How a child dies influences parents' abilities to continue their role functions as well as siblings' abilities to make and maintain friendships, and may be the basis for health care providers' decisions to exit direct care roles. Thus, facilitating a "good death"-an obvious care priority for all involved with the dying child-ought also to be a priority for the health of bereaved families and affected health care providers. Making this a care priority is complicated by a serious lack of data, as details of the last hours or weeks of a dying child or adolescent's life are largely unknown. The purpose of this paper is to identify key factors that affect the course of dying children and adolescents and that of their bereaved survivors, and to link those key factors to needed research that could produce clinically relevant findings to improve the care of these patients. Key factors described here include suffering (physical, psychological, and spiritual), communication, decision making, prognostic ambiguities, ability of the seriously ill child to give assent to research participation, and educational preparation of health care providers to give competent end-of-life care.

  5. Genetic factors affecting dental caries risk.

    PubMed

    Opal, S; Garg, S; Jain, J; Walia, I

    2015-03-01

    This article reviews the literature on genetic aspects of dental caries and provides a framework for the rapidly changing disease model of caries. The scope is genetic aspects of various dental factors affecting dental caries. The PubMed database was searched for articles with keywords 'caries', 'genetics', 'taste', 'diet' and 'twins'. This was followed by extensive handsearching using reference lists from relevant articles. The post-genomic era will present many opportunities for improvement in oral health care but will also present a multitude of challenges. We can conclude from the literature that genes have a role to play in dental caries; however, both environmental and genetic factors have been implicated in the aetiology of caries. Additional studies will have to be conducted to replicate the findings in a different population. Identification of genetic risk factors will help screen and identify susceptible patients to better understand the contribution of genes in caries aetiopathogenesis. Information derived from these diverse studies will provide new tools to target individuals and/or populations for a more efficient and effective implementation of newer preventive measures and diagnostic and novel therapeutic approaches in the management of this disease. © 2015 Australian Dental Association.

  6. Factors affecting sustainability of rural water schemes in Swaziland

    NASA Astrophysics Data System (ADS)

    Peter, Graciana; Nkambule, Sizwe E.

    The Millennium Development Goal (MDG) target to reduce the proportion of people without sustainable access to safe drinking water by the year 2015 has been met as of 2010, but huge disparities exist. Some regions, particularly Sub-Saharan Africa are lagging behind it is also in this region where up to 30% of the rural schemes are not functional at any given time. There is need for more studies on factors affecting sustainability and necessary measures which when implemented will improve the sustainability of rural water schemes. The main objective of this study was to assess the main factors affecting the sustainability of rural water schemes in Swaziland using a Multi-Criteria Analysis Approach. The main factors considered were: financial, social, technical, environmental and institutional. The study was done in Lubombo region. Fifteen functional water schemes in 11 communities were studied. Data was collected using questionnaires, checklist and focused group discussion guide. A total of 174 heads of households were interviewed. Statistical Package for Social Sciences (SPSS) was used to analyse the data and to calculate sustainability scores for water schemes. SPSS was also used to classify sustainability scores according to sustainability categories: sustainable, partially sustainable and non-sustainable. The averages of the ratings for the different sub-factors studied and the results on the sustainability scores for the sustainable, partially sustainable and non-sustainable schemes were then computed and compared to establish the main factors influencing sustainability of the water schemes. The results indicated technical and social factors as most critical while financial and institutional, although important, played a lesser role. Factors which contributed to the sustainability of water schemes were: functionality; design flow; water fetching time; ability to meet additional demand; use by population; equity; participation in decision making on operation and

  7. Failure of dissimilar material bonded joints

    NASA Astrophysics Data System (ADS)

    Konstantakopoulou, M.; Deligianni, A.; Kotsikos, G.

    2016-03-01

    Joining of materials in structural design has always been a challenge for engineers. Bolting and riveting has been used for many years, until the emergence of fusion welding which revolutionised construction in areas such as shipbuilding, automotive, infrastructure and consumer goods. Extensive research in the past 50 years has resulted in better understanding of the process and minimised the occurrence of failures associated with fusion welding such as, residual stress cracking, stress corrosion and corrosion fatigue cracking, localised reduction in mechanical properties due to microstructural changes (heat affected zone) etc. Bonding has been a technique that has been proposed as an alternative because it eliminates several of the problems associated with fusion welding. But, despite some applications it has not seen wide use. There is however a renewed interest in adhesively bonded joints, as designers look for ever more efficient structures which inevitably leads to the use and consequently joining of combinations of lightweight materials, often with fundamentally different mechanical and physical properties. This chapter provides a review of adhesively bonded joints and reports on improvements to bonded joint strength through the introduction of carbon nanotubes at the bond interface. Results from various workers in the field are reported as well as the findings of the authors in this area of research. It is obvious that there are several challenges that need to be addressed to further enhance the strength of bonded joints and worldwide research is currently underway to address those shortcomings and build confidence in the implementation of these new techniques.

  8. Factors Affecting Online Groupwork Interest: A Multilevel Analysis

    ERIC Educational Resources Information Center

    Du, Jianxia; Xu, Jianzhong; Fan, Xitao

    2013-01-01

    The purpose of the present study is to examine the personal and contextual factors that may affect students' online groupwork interest. Using the data obtained from graduate students in an online course, both student- and group-level predictors for online groupwork interest were analyzed within the framework of hierarchical linear modeling…

  9. Factors Affecting the Technology Readiness of Health Professionals

    ERIC Educational Resources Information Center

    Myers, Stephanie E.

    2010-01-01

    Federal government policies are promoting diffusion of technologies into the healthcare system. If health professionals reject the new technologies planned for the healthcare system, it could result in costly failures, delays, and workforce problems. There is a lack of knowledge about factors that affect technology readiness (TR), defined as the…

  10. Factors affecting receipt of chemotherapy in women with breast cancer

    PubMed Central

    Morimoto, Libby; Coalson, Jenna; Mowat, Fionna; O’Malley, Cynthia

    2010-01-01

    Aims: To review literature describing factors associated with receipt of chemotherapy for breast cancer, to better understand what factors are most relevant to women’s health and whether health disparities are apparent, and to assess how these factors might affect observational studies and outcomes research. Patterns of care for metastatic breast cancer, for which no standard-of-care exists, were of particular interest. Methods: Relevant studies written in English, Italian, French, or Spanish, published in 2000 or later, were identified through MEDLINE and reviewed. Review articles and clinical trials were excluded; all observational studies and surveys were considered. Articles were reviewed for any discussion of patient characteristics, hospital/physician/insurance characteristics, psychosocial characteristics, and clinical characteristics affecting receipt of chemotherapy by breast cancer patients. Results: In general, factors associated with increased likelihood of receiving chemotherapy included younger age, being Caucasian, having good general health and few co-morbidities, having more severe clinical disease, having responded well to previous treatment, and having breast cancer that is estrogen- or progesterone-receptor-negative. Many of the clinical factors found to increase the likelihood of receiving chemotherapy were consistent with current oncology guidelines. Of the relevant 19 studies identified, only six (32%) reported data specific to metastatic cancer; most studies aggregated women with stage I–IV for purposes of analysis. Conclusion: Studies of patterns of care in breast cancer treatment can help identify challenges in health care provided to particular subgroups of women and can aid researchers in designing studies that account for such factors in clinical and outcomes research. Although scarce, studies evaluating only women with metastatic breast cancer indicate that factors affecting decisions related to receipt of chemotherapy are similar

  11. [Research on bond durability among different core materials and zirconia ceramic cemented by self-adhesive resin cements].

    PubMed

    Xinyu, Luo; Xiangfeng, Meng

    2017-02-01

    This research estimated shear bond durability of zirconia and different substrates cemented by two self-adhesive resin cements (Clearfil SA Luting and RelyX U100) before and after aging conditioning. Machined zirconia ceramic discs were cemented with four kinds of core material (cobalt-chromium alloy, flowable composite resin core material, packable composite resin, and dentin) with two self-adhesive resin cements (Clearfil SA Luting and RelyX U100). All specimens were divided into eight test groups, and each test group was divided into two subgroups. Each subgroup was subjected to shear test before and after 10 000 thermal cycles. All factors (core materials, cements, and thermal cycle) significantly influenced bond durability of zirconia ceramic (P<0.00 1). After 10 000 thermal cycles, significant decrease was not observed in shear bond strength of cobalt-chromium alloy luted with Clearfil SA Luting (P>0.05); observed shear bond strength was significantly higher than those of other substrates (P<0.05). Significantly higher shear bond strength was noted in Clearfil SA Luting luted with cobalt-chromium alloy, flowable composite resin core material, and packable composite resin than that of RelyX U100 (P<0.05). However, significant difference was not observed in shear bond strength of dentin luted with Clearfil SA Luting and RelyX U100 (P>0.05). Different core materials and self-adhesive resin cements can significantly affect bond durability of zirconia ceramic. 
.

  12. 26 CFR 1.144-1 - Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 2 2012-04-01 2012-04-01 false Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds. 1.144-1 Section 1.144-1 Internal Revenue INTERNAL...) Tax Exemption Requirements for State and Local Bonds § 1.144-1 Qualified small issue bonds, qualified...

  13. 26 CFR 1.144-1 - Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 2 2013-04-01 2013-04-01 false Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds. 1.144-1 Section 1.144-1 Internal Revenue INTERNAL...) Tax Exemption Requirements for State and Local Bonds § 1.144-1 Qualified small issue bonds, qualified...

  14. 26 CFR 1.144-1 - Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds. 1.144-1 Section 1.144-1 Internal Revenue INTERNAL...) Tax Exemption Requirements for State and Local Bonds § 1.144-1 Qualified small issue bonds, qualified...

  15. 26 CFR 1.144-1 - Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 2 2014-04-01 2014-04-01 false Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds. 1.144-1 Section 1.144-1 Internal Revenue INTERNAL...) Tax Exemption Requirements for State and Local Bonds § 1.144-1 Qualified small issue bonds, qualified...

  16. 26 CFR 1.144-1 - Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 2 2011-04-01 2011-04-01 false Qualified small issue bonds, qualified student loan bonds, and qualified redevelopment bonds. 1.144-1 Section 1.144-1 Internal Revenue INTERNAL...) Tax Exemption Requirements for State and Local Bonds § 1.144-1 Qualified small issue bonds, qualified...

  17. Morphology, topography, and hardness of diffusion bonded sialon to AISI 420 at different bonding time

    NASA Astrophysics Data System (ADS)

    Ibrahim, Nor Nurulhuda Md.; Hussain, Patthi; Awang, Mokhtar

    2015-07-01

    Sialon and AISI 420 martensitic stainless steel were diffusion bonded in order to study the effect of bonding time on reaction layer's growth. Joining of these materials was conducted at 1200°C under a uniaxial pressure of 17 MPa in a vacuum ranging from 5.0 to 8.0×10-6 Torr with bonding time varied for 0.5, 2, and 3 h. Thicker reaction layer was formed in longer bonded sample since the elements from sialon could diffuse further into the steel. Sialon retained its microstructure but it was affected at the initial contact with the steel to form the new interface layer. Diffusion layer grew toward the steel and it was segregated with the parent steel as a result of the difference in properties between these regions. The segregation formed a stream-like structure and its depth decreased when the bonding time was increased. The microstructure of the steel transformed into large grain size with precipitates. Prolonging the bonding time produced more precipitates in the steel and reduced the steel thickness as well. Interdiffusions of elements occurred between the joined materials and the concentrations were decreasing toward the steel and vice versa. Silicon easily diffused into the steel because it possessed lower ionization potential compared to nitrogen. Formation of silicide and other compounds such as carbides were detected in the interface layer and steel grain boundary, respectively. These compounds were harmful due to silicide brittleness and precipitation of carbides in the grain boundary might cause intergranular corrosion cracking. Sialon retained its hardness but it dropped very low at the interface layer. The absence of crack at the joint in all samples could be contributed from the ductility characteristic of the reaction layer which compensated the residual stress that was formed upon the cooling process.

  18. Enamel shear bond strength of two orthodontic self-etching bonding systems compared to Transbond™ XT.

    PubMed

    Hellak, Andreas; Rusdea, Patrick; Schauseil, Michael; Stein, Steffen; Korbmacher-Steiner, Heike Maria

    2016-11-01

    The aim of this in vitro study was to compare the shear bond strength (SBS) and Adhesive Remnant Index (ARI) scores of two self-etching no-mix adhesives (Prompt L-Pop™ and Scotchbond™) for orthodontic appliances to the commonly used total etch system Transbond XT™ (in combination with phosphoric acid). In all, 60 human premolars were randomly divided into three groups of 20 specimens each. In group 1 (control), brackets were bonded with Transbond™ XT primer. Prompt L-Pop™ (group 2) and Scotchbond™ Universal (group 3) were used in the experimental groups. Lower premolar brackets were bonded by light curing the adhesive. After 24 h of storage, the shear bond strength (SBS) was measured using a Zwicki 1120 testing machine. The adhesive remnant index (ARI) was determined under 10× magnification. The Kruskal-Wallis test was used to statistically compare the SBS and the ARI scores. No significant differences in the SBS between any of the experimental groups were detected (group 1: 15.49 ± 3.28 MPa; group 2: 13.89 ± 4.95 MPa; group 3: 14.35 ± 3.56 MPa; p = 0.489), nor were there any significant differences in the ARI scores (p = 0.368). Using the two self-etching no-mix adhesives (Prompt L-Pop™ and Scotchbond™) for orthodontic appliances does not affect either the SBS or ARI scores in comparison with the commonly used total-etch system Transbond™ XT. In addition, Scotchbond™ Universal supports bonding on all types of surfaces (enamel, metal, composite, and porcelain) with no need for additional primers. It might therefore be helpful for simplifying bonding in orthodontic procedures.

  19. Factors affecting the periapical healing process of endodontically treated teeth

    PubMed Central

    Holland, Roberto; Gomes, João Eduardo; Cintra, Luciano Tavares Angelo; Queiroz, Índia Olinta de Azevedo; Estrela, Carlos

    2017-01-01

    Abstract Tissue repair is an essential process that reestablishes tissue integrity and regular function. Nevertheless, different therapeutic factors and clinical conditions may interfere in this process of periapical healing. This review aims to discuss the important therapeutic factors associated with the clinical protocol used during root canal treatment and to highlight the systemic conditions associated with the periapical healing process of endodontically treated teeth. The antibacterial strategies indicated in the conventional treatment of an inflamed and infected pulp and the modulation of the host's immune response may assist in tissue repair, if wound healing has been hindered by infection. Systemic conditions, such as diabetes mellitus and hypertension, can also inhibit wound healing. The success of root canal treatment is affected by the correct choice of clinical protocol. These factors are dependent on the sanitization process (instrumentation, irrigant solution, irrigating strategies, and intracanal dressing), the apical limit of the root canal preparation and obturation, and the quality of the sealer. The challenges affecting the healing process of endodontically treated teeth include control of the inflammation of pulp or infectious processes and simultaneous neutralization of unpredictable provocations to the periapical tissue. Along with these factors, one must understand the local and general clinical conditions (systemic health of the patient) that affect the outcome of root canal treatment prediction. PMID:29069143

  20. Defying ageing: An expectation for dentine bonding with universal adhesives?

    PubMed

    Zhang, Zheng-yi; Tian, Fu-cong; Niu, Li-na; Ochala, Kirsten; Chen, Chen; Fu, Bai-ping; Wang, Xiao-yan; Pashley, David H; Tay, Franklin R

    2016-02-01

    The present study evaluated the long-term dentine bonding effectiveness of five universal adhesives in etch-and-rinse or self-etch mode after 12 months of water-ageing. The adhesives evaluated included All-Bond Universal, Clearfil Universal Bond, Futurabond U Prime&Bond Elect and Scotchbond Universal. Microtensile bond strength and transmission electron microscopy of the resin-dentine interfaces created in human coronal dentine were examined after 24h or 12 months. Microtensile bond strength were significantly affected by bonding strategy (etch-and-rinse vs self-etch) and ageing (24h vs 12 months). All subgroups showed significantly decreased bond strength after ageing except for Prime&Bond Elect and Scotchbond Universal used in self-etch mode. All five adhesives employed in etch-and-rinse mode exhibited ultrastructural features characteristic of collagen degradation and resin hydrolysis. A previously-unobserved inside-out collagen degradation pattern was identified in hybrid layers created by 10-MDP containing adhesives (All-Bond Universal, Scotchbond Universal and Clearfil Universal Bond) in the etch-and-rinse mode, producing partially degraded collagen fibrils with intact periphery and a hollow core. In the self-etch mode, all adhesives except for Prime&Bond Elect exhibited degradation of the collagen fibrils along the thin hybrid layers. The three 10-MDP containing universal adhesives did not protect surface collagen fibrils from degradation when bonding was performed in the self-etch mode. Despite the adjunctive conclusion that bonds created by universal adhesives in the self-etch bonding mode are more resistant to decline in bond strength when compared with those bonds created using the etch-and-rinse mode, bonds created by universal adhesives are generally incapable of defying ageing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Factors affecting outcome in ocular myasthenia gravis.

    PubMed

    Mazzoli, Marco; Ariatti, Alessandra; Valzania, Franco; Kaleci, Shaniko; Tondelli, Manuela; Nichelli, Paolo F; Galassi, Giuliana

    2018-01-01

    50%-60% of patients with ocular myasthenia gravis (OMG) progress to generalized myasthenia gravis (GMG) within two years. The aim of our study was to explore factors affecting prognosis of OMG and to test the predictive role of several independent clinical variables. We reviewed a cohort of 168 Caucasian patients followed from September 2000 to January 2016. Several independent variables were considered as prognostic factors: gender, age of onset, results on electrophysiological tests, presence and level of antibodies against acetylcholine receptors (AChR Abs), treatments, thymic abnormalities. The primary outcome was the progression to GMG and/or the presence of bulbar symptoms. Secondary outcomes were either achievement of sustained minimal manifestation status or worsening in ocular quantitative MG subscore (O-QMGS) or worsening in total QMG score (T-QMGS), assessed by Myasthenia Gravis Foundation of America (MGFA) quantitative scores. Changes in mental and physical subscores of health-related quality of life (HRQoL) were assessed with SF-36 questionnaire. Variance analysis was used to interpret the differences between AChR Ab titers at different times of follow up among the generalized and non-generalized patients. Conversion to GMG occurred in 18.4% of patients; it was significantly associated with sex, later onset of disease and anti-AChR Ab positivity. Antibody titer above the mean value of 25.8 pmol/mL showed no significant effect on generalization. Sex and late onset of disease significantly affected T-QMGS worsening. None of the other independent variables significantly affected O-QMGS and HRQoL. Sex, later onset and anti-AChR Ab positivity were significantly associated with clinical worsening.

  2. Solute's perspective on how trimethylamine oxide, urea, and guanidine hydrochloride affect water's hydrogen bonding ability.

    PubMed

    Pazos, Ileana M; Gai, Feng

    2012-10-18

    While the thermodynamic effects of trimethylamine oxide (TMAO), urea, and guanidine hydrochloride (GdnHCl) on protein stability are well understood, the underlying mechanisms of action are less well characterized and, in some cases, even under debate. Herein, we employ the stretching vibration of two infrared (IR) reporters, i.e., nitrile (C≡N) and carbonyl (C═O), to directly probe how these cosolvents mediate the ability of water to form hydrogen bonds with the solute of interest, e.g., a peptide. Our results show that these three agents, despite having different effects on protein stability, all act to decrease the strength of the hydrogen bonds formed between water and the infrared probe. While the behavior of TMAO appears to be consistent with its protein-protecting ability, those of urea and GdnHCl are inconsistent with their role as protein denaturants. The latter is of particular interest as it provides strong evidence indicating that although urea and GdnHCl can perturb the hydrogen-bonding property of water their protein-denaturing ability does not arise from a simple indirect mechanism.

  3. Factors affecting sexual function in menopause: A review article.

    PubMed

    Nazarpour, Soheila; Simbar, Masoumeh; Tehrani, Fahimeh Ramezani

    2016-08-01

    This study aimed to systematically review the articles on factors affecting sexual function during menopause. Searching articles indexed in Pubmed, Science Direct, Iranmedex, EMBASE, Scopus, and Scientific Information Database databases, a total number of 42 studies published between 2003 and 2013 were selected. Age, estrogen deficiency, type of menopause, chronic medical problems, partner's sex problems, severity of menopause symptoms, dystocia history, and health status were the physical factors influencing sexual function of menopausal women. There were conflicting results regarding the amount of androgens, hormonal therapy, exercise/physical activity, and obstetric history. In the mental-emotional area, all studies confirmed the impact of depression and anxiety. Social factors, including smoking, alcohol consumption, the quality of relationship with husband, partner's loyalty, sexual knowledge, access to health care, a history of divorce or the death of a husband, living apart from a spouse, and a negative understanding of women's health were found to affect sexual function; however, there were conflicting results regarding the effects of education, occupation, socioeconomic status, marital duration, and frequency of sexual intercourse. Copyright © 2016. Published by Elsevier B.V.

  4. Dissecting the machinery that introduces disulfide bonds in Pseudomonas aeruginosa.

    PubMed

    Arts, Isabelle S; Ball, Geneviève; Leverrier, Pauline; Garvis, Steven; Nicolaes, Valérie; Vertommen, Didier; Ize, Bérengère; Tamu Dufe, Veronica; Messens, Joris; Voulhoux, Romé; Collet, Jean-François

    2013-12-10

    Disulfide bond formation is required for the folding of many bacterial virulence factors. However, whereas the Escherichia coli disulfide bond-forming system is well characterized, not much is known on the pathways that oxidatively fold proteins in pathogenic bacteria. Here, we report the detailed unraveling of the pathway that introduces disulfide bonds in the periplasm of the human pathogen Pseudomonas aeruginosa. The genome of P. aeruginosa uniquely encodes two DsbA proteins (P. aeruginosa DsbA1 [PaDsbA1] and PaDsbA2) and two DsbB proteins (PaDsbB1 and PaDsbB2). We found that PaDsbA1, the primary donor of disulfide bonds to secreted proteins, is maintained oxidized in vivo by both PaDsbB1 and PaDsbB2. In vitro reconstitution of the pathway confirms that both PaDsbB1 and PaDsbB2 shuttle electrons from PaDsbA1 to membrane-bound quinones. Accordingly, deletion of both P. aeruginosa dsbB1 (PadsbB1) and PadsbB2 is required to prevent the folding of several P. aeruginosa virulence factors and to lead to a significant decrease in pathogenicity. Using a high-throughput proteomic approach, we also analyzed the impact of PadsbA1 deletion on the global periplasmic proteome of P. aeruginosa, which allowed us to identify more than 20 new potential substrates of this major oxidoreductase. Finally, we report the biochemical and structural characterization of PaDsbA2, a highly oxidizing oxidoreductase, which seems to be expressed under specific conditions. By fully dissecting the machinery that introduces disulfide bonds in P. aeruginosa, our work opens the way to the design of novel antibacterial molecules able to disarm this pathogen by preventing the proper assembly of its arsenal of virulence factors. The human pathogen Pseudomonas aeruginosa causes life-threatening infections in immunodepressed and cystic fibrosis patients. The emergence of P. aeruginosa strains resistant to all of the available antibacterial agents calls for the urgent development of new antibiotics

  5. [Research progress of bonding strength between porcelain veneer and enamel].

    PubMed

    Cheng, Hong; Zhang, Fu-qiang

    2014-02-01

    Porcelain veneer had gained more and more attention in dental clinical applications due to its advantages such as good esthetic effects and minor invasiveness. The reliable and consistent adhesive bonding were the key to success. The enamel which featured high mineralization and low moisture would be the ideal bonding part for porcelain veneer. This article was aimed to summarize the research progress regarding to those factors that might had effect on the bonding strength between the porcelain veneer and the enamel including the restoration types of resin adhesives and bonding surface preparations.

  6. Analysis on factors affecting consumers decision on purchasing simple-type houses

    NASA Astrophysics Data System (ADS)

    Rumintang, A.; Sholichin, I.

    2018-01-01

    In line with the increase of the population and the need of comfortable houses, as affected by modernization era, the house demand is getting higher. Hence, conducting a research on consumers need and want in buying a house should be seriously attempted to succeed marketing activity. Using an analysis consumers’ behavior, the researcher will know few affecting factors related to consumers’ satisfaction in buying a house. Among other, the factors in question include: house price, house condition, facilities, location and accessability. The sample of this research was drawn from the residents of Graha Asri Housing, Taman Bulang Permai, and Sukodono Permai. Based on the analysis and discussion, some conclusions are made as follow: the factors and variables affecting the consumers’ decision on each choice of house is different and also the same variables on three sources of data include housing atmosphere, cleaning service, ease of access to shopping center, health clinics or hospitals, tourism spot, schools, and the bus station.

  7. Thermochemical factors affecting the dehalogenation of aromatics.

    PubMed

    Sadowsky, Daniel; McNeill, Kristopher; Cramer, Christopher J

    2013-12-17

    Halogenated aromatics are one of the largest chemical classes of environmental contaminants, and dehalogenation remains one of the most important processes by which these compounds are degraded and detoxified. The thermodynamic constraints of aromatic dehalogenation reactions are thus important for understanding the feasibility of such reactions and the redox conditions necessary for promoting them. Accordingly, the thermochemical properties of the (poly)fluoro-, (poly)chloro-, and (poly)bromobenzenes, including standard enthalpies of formation, bond dissociation enthalpies, free energies of reaction, and the redox potentials of Ar-X/Ar-H couples, were investigated using a validated density functional protocol combined with continuum solvation calculations when appropriate. The results highlight the fact that fluorinated aromatics stand distinct from their chloro- and bromo- counterparts in terms of both their relative thermodynamic stability toward dehalogenation and how different substitution patterns give rise to relevant properties, such as bond strengths and reduction potentials.

  8. 14 CFR Appendix B to Part 1215 - Factors Affecting Standard Charges

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... DATA RELAY SATELLITE SYSTEM (TDRSS) Pt. 1215, App. B Appendix B to Part 1215—Factors Affecting Standard Charges Charges for services shall be determined by multiplying the factors below by the base rates for...

  9. Other Factors That Affect Heart Disease: Birth Control Pills

    MedlinePlus

    ... Heart Handbook for Women Other Factors That Affect Heart Disease Birth Control Pills Studies show that women who ... t had any more complications because of my heart disease." — Diane Pay attention to diabetes. Levels of glucose, ...

  10. Reappraising factors affecting mourning dove perch coos

    USGS Publications Warehouse

    Sayre, M.W.; Atkinson, R.D.; Baskett, T.S.; Haas, G.H.

    1978-01-01

    Results confirmed pairing as the primary factor influencing perch-cooing rates of wild mourning doves (Zenaida macroura). Marked unmated males cooed at substantially higher rates (6.2x) than mated males, had greater probability of cooing (2.3x) during 3-minute periods, and continued cooing longer each morning than mated males. Population density was not a major factor affecting cooing. Unmated males cooed more frequently in the presence of other cooing doves (P < 0.05) than when alone, but the number of additional doves above 1 was unimportant. Cooing rates of both mated and unmated males on areas with dissimilar dove densities were not significantly different. Within limits of standard call-count procedure, weather exerted no detectable influence on cooing.

  11. Bonding Social Capital in Low-Income Neighborhoods

    ERIC Educational Resources Information Center

    Brisson, Daniel S.; Usher, Charles L.

    2005-01-01

    Social capital has recently become a guiding theoretical framework for family interventions in low-income neighborhoods. In the context of the Annie E. Casey Foundation's Making Connections initiative, this research uses hierarchical linear modeling to examine how neighborhood characteristics and resident participation affect bonding social…

  12. 27 CFR 24.147 - Operations bond or unit bond.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Operations bond or unit... BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Establishment and Operations Bonds and Consents of Surety § 24.147 Operations bond or unit bond. Notwithstanding the provisions of § 24.146, each person...

  13. Laser Engineered Net Shaping of Nickel-Based Superalloy Inconel 718 Powders onto AISI 4140 Alloy Steel Substrates: Interface Bond and Fracture Failure Mechanism

    PubMed Central

    Kim, Hoyeol; Cong, Weilong; Zhang, Hong-Chao; Liu, Zhichao

    2017-01-01

    As a prospective candidate material for surface coating and repair applications, nickel-based superalloy Inconel 718 (IN718) was deposited on American Iron and Steel Institute (AISI) 4140 alloy steel substrate by laser engineered net shaping (LENS) to investigate the compatibility between two dissimilar materials with a focus on interface bonding and fracture behavior of the hybrid specimens. The results show that the interface between the two dissimilar materials exhibits good metallurgical bonding. Through the tensile test, all the fractures occurred in the as-deposited IN718 section rather than the interface or the substrate, implying that the as-deposited interlayer bond strength is weaker than the interfacial bond strength. From the fractography using scanning electron microscopy (SEM) and energy disperse X-ray spectrometry (EDS), three major factors affecting the tensile fracture failure of the as-deposited part are (i) metallurgical defects such as incompletely melted powder particles, lack-of-fusion porosity, and micropores; (ii) elemental segregation and Laves phase, and (iii) oxide formation. The fracture failure mechanism is a combination of all these factors which are detrimental to the mechanical properties and structural integrity by causing premature fracture failure of the as-deposited IN718. PMID:28772702

  14. Laser Engineered Net Shaping of Nickel-Based Superalloy Inconel 718 Powders onto AISI 4140 Alloy Steel Substrates: Interface Bond and Fracture Failure Mechanism.

    PubMed

    Kim, Hoyeol; Cong, Weilong; Zhang, Hong-Chao; Liu, Zhichao

    2017-03-25

    As a prospective candidate material for surface coating and repair applications, nickel-based superalloy Inconel 718 (IN718) was deposited on American Iron and Steel Institute (AISI) 4140 alloy steel substrate by laser engineered net shaping (LENS) to investigate the compatibility between two dissimilar materials with a focus on interface bonding and fracture behavior of the hybrid specimens. The results show that the interface between the two dissimilar materials exhibits good metallurgical bonding. Through the tensile test, all the fractures occurred in the as-deposited IN718 section rather than the interface or the substrate, implying that the as-deposited interlayer bond strength is weaker than the interfacial bond strength. From the fractography using scanning electron microscopy (SEM) and energy disperse X-ray spectrometry (EDS), three major factors affecting the tensile fracture failure of the as-deposited part are (i) metallurgical defects such as incompletely melted powder particles, lack-of-fusion porosity, and micropores; (ii) elemental segregation and Laves phase, and (iii) oxide formation. The fracture failure mechanism is a combination of all these factors which are detrimental to the mechanical properties and structural integrity by causing premature fracture failure of the as-deposited IN718.

  15. Low-temperature poly(oxymethylene) direct bonding via self-assembled monolayer

    NASA Astrophysics Data System (ADS)

    Fu, Weixin; Ma, Bo; Kuwae, Hiroyuki; Shoji, Shuichi; Mizuno, Jun

    2018-02-01

    A direct bonding of poly(oxymethylene) (POM) was feasible at 100 °C by using self-assembled monolayer (SAM) as a surface modification method. (3-aminopropyl)triethoxysilane (APTES) and (3-glycidyloxypropyl)trimethoxysilane (GOPTS) were used in our work. X-ray photoelectron spectroscopy showed that both APTES and GOPTS modified the POM surface successfully. Bonding strength evaluation revealed that surface modification was affected by pretreatment (VUV/O3) process time. In addition, the bonding condition with highest strength had an average strength of 372 kPa. This technology is expected to be used in packaging for micro-/nano-electromechanical systems, such as biomedical devices.

  16. Organisational Factors Affecting Policy and Programme Decision Making in a Public Health Policy Environment

    ERIC Educational Resources Information Center

    Zardo, Pauline; Collie, Alex; Livingstone, Charles

    2015-01-01

    Organisational factors can affect the success of interventions aimed at increasing research use. Research is needed to identify organisational factors affecting research use in specific public health policy contexts. Qualitative interviews with decision makers from a specific public health context identified a range of organisational factors that…

  17. Factors affecting dental service quality.

    PubMed

    Bahadori, Mohammadkarim; Raadabadi, Mehdi; Ravangard, Ramin; Baldacchino, Donia

    2015-01-01

    Measuring dental clinic service quality is the first and most important factor in improving care. The quality provided plays an important role in patient satisfaction. The purpose of this paper is to identify factors affecting dental service quality from the patients' viewpoint. This cross-sectional, descriptive-analytical study was conducted in a dental clinic in Tehran between January and June 2014. A sample of 385 patients was selected from two work shifts using stratified sampling proportional to size and simple random sampling methods. The data were collected, a self-administered questionnaire designed for the purpose of the study, based on the Parasuraman and Zeithaml's model of service quality which consisted of two parts: the patients' demographic characteristics and a 30-item questionnaire to measure the five dimensions of the service quality. The collected data were analysed using SPSS 21.0 and Amos 18.0 through some descriptive statistics such as mean, standard deviation, as well as analytical methods, including confirmatory factor. Results showed that the correlation coefficients for all dimensions were higher than 0.5. In this model, assurance (regression weight=0.99) and tangibility (regression weight=0.86) had, respectively, the highest and lowest effects on dental service quality. The Parasuraman and Zeithaml's model is suitable to measure quality in dental services. The variables related to dental services quality have been made according to the model. This is a pioneering study that uses Parasuraman and Zeithaml's model and CFA in a dental setting. This study provides useful insights and guidance for dental service quality assurance.

  18. Exploring Factors that Affect Purchase Intention of Athletic Team Merchandise

    ERIC Educational Resources Information Center

    Lee, Donghun; Trail, Galen T.; Lee, Cindy; Schoenstedt, Linda J.

    2013-01-01

    The purpose of this study was to test a structural model to determine which psychosocial constructs affected the purchase intention of athletic team merchandise (ATM). Results from the analyses indicated that the twelve-factor ATM model fit the data from collegiate athletic events well, explaining the various impact factors that lead to purchase…

  19. Influence of hydrophilic pre-treatment on resin bonding to zirconia ceramics.

    PubMed

    Noro, Akio; Kameyama, Atsushi; Haruyama, Akiko; Takahashi, Toshiyuki

    2015-01-01

    Atmospheric plasma or ultraviolet (UV) treatment alters the surface characteristics of tetragonal zirconia polycrystal (TZP), increasing its hydrophilicity by reducing the contact angle against water to zero. This suggests that such treatment would increase the wettability of bonding resin. The purpose of this study was to determine how increasing the hydrophilicity of TZP through plasma irradiation, UV treatment, or application of ceramic primer affected initial bonding with resin composites. Here, the effect of each pre-treatment on the hydrophilicity of TZP surfaces was determined by evaluating change in shear bond strength. Plasma irradiation, UV, or ceramic primer pre-treatment showed no significant effect on bonding strength between TZP surfaces and resin composites. In addition, alumina blasting yielded no significant increase in bond strength. Plasma irradiation, UV treatment, or ceramic primer pre-treatment did not lead to significant increase in bond strength between TZP and resin composites.

  20. 29 CFR 784.118 - The exemption is intended for work affected by natural factors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false The exemption is intended for work affected by natural...(a)(5) Exemption § 784.118 The exemption is intended for work affected by natural factors. As... that are controlled or materially affected by natural factors or elements, such as the vicissitudes of...

  1. 29 CFR 784.118 - The exemption is intended for work affected by natural factors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false The exemption is intended for work affected by natural...(a)(5) Exemption § 784.118 The exemption is intended for work affected by natural factors. As... that are controlled or materially affected by natural factors or elements, such as the vicissitudes of...

  2. Experimental and FE displacement and polymerization stress of bonded restorations as a function of the C-Factor, volume and substrate stiffness.

    PubMed

    Boaro, Letícia Cristina Cidreira; Brandt, William Cunha; Meira, Josete Barbosa Cruz; Rodrigues, Flávia Pires; Palin, William M; Braga, Roberto Ruggiero

    2014-02-01

    To determine the free surface displacement of resin-composite restorations as a function of the C-Factor, volume and substrate stiffness, and to compare the results with interfacial stress values evaluated by finite element analysis (FEA). Surface displacement was determined by an extensometer using restorations with 4 or 6mm diameter and 1 or 2mm depth, prepared in either bovine teeth or glass. The maximum displacement of the free surface was monitored for 5 min from the start of photoactivation, at an acquisition rate of 1s(-1). Axisymmetric cavity models were performed by FEA. Structural stiffness and maximum stresses were investigated. For glass, displacement showed a stronger correlation with volume (r=0.771) than with C-Factor (r=0.395, p<0.001 for both). For teeth, a stronger correlation was found with C-Factor (r=0.709; p<0.001) than with volume (r=0.546, p<0.001). For similar dimensions, stress and displacement were defined by stiffness. Simultaneous increases in volume and C-Factor led to increases in stress and surface displacement. Maximum stresses were located at the cavosurface angle, internal angle (glass) and at the dentine-enamel junction (teeth). The displacement of the restoration's free surface was related to interfacial stress development. Structural stiffness seems to affect the shrinkage stress at the tooth/resin-composite interface in bonded restorations. Deep restorations are always problematic because they showed high shear stress, regardless of their width. FEA is the only tool capable of detecting shear stress due to polymerization as there is still no reliable experimental alternative. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Formal Classroom Observations: Factors That Affect Their Success

    ERIC Educational Resources Information Center

    Zaidi, Zeba

    2017-01-01

    Formal class room observation is a very delicate topic in any educational institution. It involves a series of emotions and sentiments that come with the package. In this paper, the researcher will attempt to analyze the factors that affect the process in a relatively significant manner and thereby contribute greatly to the success or failure of…

  4. Factors affecting patient compliance with compressive brace therapy for pectus carinatum.

    PubMed

    Kang, Du-Young; Jung, Junho; Chung, Sangho; Cho, Jinkyung; Lee, Sungsoo

    2014-12-01

    The aim of this study was to identify factors affecting patient compliance with brace therapy for pectus carinatum. Eighty-six pectus carinatum patients who started brace therapy from August 2008 to November 2011 were included in this study. Patients were divided into two groups: patients who wore the brace for ≥6 months (compliance group) or patients who wore the brace for <6 months (non-compliance group). Factors affecting patient compliance were assessed at the last day of follow-up with a multiple-choice questionnaire. The questionnaire comprised seven items: pain at compression site, skin problems on compression area, confidence in brace treatment, shame, discomfort, initial result of bracing treatment and total number of factors affecting patient compliance. Eighty-six patients completed the survey, including seven (8.1%) female patients and 79 (91.9%) male patients, with a mean age of 12.0 years at the time of treatment (range, 3-20 years). The initial result of the compression period (P <0.001) and total number of factors affecting patient compliance (P <0.05) were significant predictors of patient compliance. An initial successful result of the compression period may increase patient compliance during treatment for pectus carinatum. Additional efforts to decrease pain, skin problems, shame and discomfort, and to give confidence may be beneficial in increasing compliance with bracing treatment. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  5. Rotational Spectra of Hydrogen Bonded Networks of Amino Alcohols

    NASA Astrophysics Data System (ADS)

    Zhang, Di; Zwier, Timothy S.

    2014-06-01

    The rotational spectra of several different amino alcohols including D/L-allo-threoninol, 2-amino-1,3-propanediol and 1,3-diamino-2-propanol over the 6.5-18.5 GHz range have been investigated under jet-cooled conditions using chirped-pulsed Fourier transform microwave spectroscopy. Despite the small size of these molecules, a great variety of conformations have been observed in the molecular expansion. While the NH2 group is typically thought of as a H-bond acceptor, it often acts both as acceptor and donor in forming H-bonded networks. With three adjacent H-bonding substituents (a combination of OH and NH2 groups), many different hydrogen bonding patterns are possible, including H-bonded chains and H-bonded cycles. Since many of these structures differ primarily by the relative orientation of the H-atoms, the analysis of these rotational spectra are challenging. Only through an exhaustive conformational search and the comparison with the experimental rotational constants, nuclear quadrupolar splittings, and line strengths are we able to understand the complex nature of these interactions. The ways in which the presence and number of NH2 groups affects the relative energies, and distorts the structures will be explored.

  6. Factors affecting scholastic performances of adolescents.

    PubMed

    Shashidhar, Saraswati; Rao, Chandrika; Hegde, Radhakrishna

    2009-05-01

    The present study aims at recognizing the social influence, study habits and health factors affecting scholastic performances of adolescents and to compare these factors among the adolescents between two categories of school. A total of 1230 adolescents (13-18 yrs) were screened. Data was collected by personal interview, using the teenage screening questionnaire, Trivandrum, between May 2004 and November 2005. A total 615 students from corporation and private schools were studied. 39.76% (489) were high achievers, 13.5% (166) were low achievers with p < 0.001. In the low achievers, 12.03% were from the corporation schools and 1.46% from private schools. The incidence of poor study habits and social factors were increased in low achievers of corporation schools. On multivariate analysis, the predictor variables for poor scholastic performance were adolescent having refractory error, not having help for study at home, not doing home work regularly, not solving question bank papers and reading only before examinations. It is feasible and worthwhile to identify the determinants of scholastic performance and plan intervention strategies at each school. The results of this study highlight the importance of implementing newer strategies, focusing on strict study patterns and creating the conducive school and home environment for study, so as to achieve better scholastic performances.

  7. New method for rapid testing of bond strength for wood adhesives

    Treesearch

    James M. Wescott; Michael J. Birkeland; Amy E. Traska; Charles R. Frihart; Brice N. Dally

    2007-01-01

    In developing new adhesives for wood bonding, the testing of bond performance can often be a limiting factor in the development process. Evaluating the bond performance of an adhesive that can be prepared in less than a day often takes several days using standard performance tests. This testing slows the development process and may cause a company to abandon a...

  8. Factors affecting hydrogen-tunneling contribution in hydroxylation reactions promoted by oxoiron(IV) porphyrin π-cation radical complexes.

    PubMed

    Cong, Zhiqi; Kinemuchi, Haruki; Kurahashi, Takuya; Fujii, Hiroshi

    2014-10-06

    Hydrogen atom transfer with a tunneling effect (H-tunneling) has been proposed to be involved in aliphatic hydroxylation reactions catalyzed by cytochrome P450 and synthetic heme complexes as a result of the observation of large hydrogen/deuterium kinetic isotope effects (KIEs). In the present work, we investigate the factors controlling the H-tunneling contribution to the H-transfer process in hydroxylation reaction by examining the kinetics of hydroxylation reactions at the benzylic positions of xanthene and 1,2,3,4-tetrahydronaphthalene by oxoiron(IV) 5,10,15,20-tetramesitylporphyrin π-cation radical complexes ((TMP(+•))Fe(IV)O(L)) under single-turnover conditions. The Arrhenius plots for these hydroxylation reactions of H-isotopomers have upwardly concave profiles. The Arrhenius plots of D-isotopomers, clear isosbestic points, and product analysis rule out the participation of thermally dependent other reaction processes in the concave profiles. These results provide evidence for the involvement of H-tunneling in the rate-limiting H-transfer process. These profiles are simulated using an equation derived from Bell's tunneling model. The temperature dependence of the KIE values (k(H)/k(D)) determined for these reactions indicates that the KIE value increases as the reaction temperature becomes lower, the bond dissociation energy (BDE) of the C-H bond of a substrate becomes higher, and the reactivity of (TMP(+•))Fe(IV)O(L) decreases. In addition, we found correlation of the slope of the ln(k(H)/k(D)) - 1/T plot and the bond strengths of the Fe═O bond of (TMP(+•))Fe(IV)O(L) estimated from resonance Raman spectroscopy. These observations indicate that these factors modulate the extent of the H-tunneling contribution by modulating the ratio of the height and thickness of the reaction barrier.

  9. The Impact of Debt Limitations and Referenda Requirements on the Cost of School District Bond Issues

    ERIC Educational Resources Information Center

    Harris, Mary H.; Munley, Vincent G.

    2011-01-01

    One distinction between the markets for corporate and municipal bonds involves institutional constraints that apply to some municipal bond issues. This research focuses on how public finance institutions, in particular explicit debt limits and referenda requirements, affect the borrowing cost of individual school district bond issues. The…

  10. Factors affecting maintenance overlay ride quality : 1996 rideability status.

    DOT National Transportation Integrated Search

    1997-01-01

    In early 1996, the Virginia Transportation Research Council initiated a formal analysis of the factors affecting overlay ride quality. As part of that effort, a statewide, multi-year survey of the ride quality for both new overlays and pavement await...

  11. External factors affecting data acquisition during corneal topography examination.

    PubMed

    González-Méijome, José Manuel; Queirós, Antonio; Jorge, Jorge; Fernandes, Paulo; Cerviño, Alejandro; de Almeida, José Borges

    2007-03-01

    To analyze the factors affecting data acquisition during corneal topography examination with the Medmont E-300 videokeratoscope and to provide strategies to minimize their effects. Sixty eyes from thirty young adults were examined. A second observer registered incidences with the potential to affect data acquisition. Those factors were correlated with the difficulty of measurements as judged subjectively by the practitioner who performed the examination. Measurements of axial curvature were analyzed to evaluate the variability expressed as intrasession and intersession coefficient of variation and the standard error of the mean (SEM). The level of difficulty rated by the practitioner was in general low, with 70% of the eyes being easy or very easy to measure. For the remaining 30% of the eyes, corneal topography measurements were considered to be difficult (27%) or very difficult (3%). Of the external parameters investigated, only fixation instability (P<0.001, chi2) and the need for head repositioning (P=0.024, chi2) were associated significantly with a higher level of difficulty, as rated subjectively by the practitioner. Further analysis showed that some external factors, including those previously mentioned and others related to tear instability, affect the variability of measurements at certain corneal locations, particularly in the vertical meridian when related to tear instability and in the horizontal meridian when related to the need for head repositioning on the chin rest owing to physiognomy interferences with the keratoscope cone. Intersession SEM improved when three readings from each session were considered. The level of subjective difficulty found during videokeratoscopy examination is correlated strongly with fixation instability and the need for head reorientation in the chin rest, whereas tear-related events seem to be less relevant in the practitioner perception of test ease or difficulty. Those factors have relevance in measurement variability.

  12. Factors affecting 30-month survival in lung cancer patients.

    PubMed

    Mahesh, P A; Archana, S; Jayaraj, B S; Patil, Shekar; Chaya, S K; Shashidhar, H P; Sunitha, B S; Prabhakar, A K

    2012-10-01

    Age adjusted incidence rate of lung cancer in India ranges from 7.4 to 13.1 per 100,000 among males and 3.9 to 5.8 per 100,000 among females. The factors affecting survival in lung cancer patients in India are not fully understood. The current study was undertaken to evaluate the factors affecting survival in patients diagnosed with lung cancer attending a tertiary care cancer institute in Bangalore, Karnataka, India. Consecutive patients with primary lung cancer attending Bangalore Institute of Oncology, a tertiary care centre at Bangalore, between 2006 and 2009 were included. Demographic, clinical, radiological data were collected retrospectively from the medical records. A total of 170 consecutive subjects (128 males, 42 females) diagnosed to have lung cancer; 151 non-small cell lung cancer (NSCLC) and 19 small cell lung cancer (SCLC) were included. A higher proportion of never-smokers (54.1%) were observed, mostly presenting below the age of 60 yr. Most subjects were in stage IV and III at the time of diagnosis. More than 50 per cent of patients presented with late stage lung cancer even though the duration of symptoms is less than 2 months. The 30-month overall survival rates for smokers and never-smokers were 32 and 49 per cent, respectively. No significant differences were observed in 30 month survival based on age at presentation, gender and type of lung cancer. Cox proportional hazards model identified never-smokers and duration of symptoms less than 1 month as factors adversely affecting survival. Our results showed that lung cancer in Indians involved younger subjects and associated with poorer survival as compared to other ethnic population. Studies on large sample need to be done to evaluate risk factors in lung cancer patients.

  13. Factors affecting 30-month survival in lung cancer patients

    PubMed Central

    Mahesh, P.A.; Archana, S.; Jayaraj, B.S.; Patil, Shekar; Chaya, S.K.; Shashidhar, H.P.; Sunitha, B.S.; Prabhakar, A.K.

    2012-01-01

    Background & objectives: Age adjusted incidence rate of lung cancer in India ranges from 7.4 to 13.1 per 100,000 among males and 3.9 to 5.8 per 100,000 among females. The factors affecting survival in lung cancer patients in India are not fully understood. The current study was undertaken to evaluate the factors affecting survival in patients diagnosed with lung cancer attending a tertiary care cancer institute in Bangalore, Karnataka, India. Methods: Consecutive patients with primary lung cancer attending Bangalore Institute of Oncology, a tertiary care centre at Bangalore, between 2006 and 2009 were included. Demographic, clinical, radiological data were collected retrospectively from the medical records. Results: A total of 170 consecutive subjects (128 males, 42 females) diagnosed to have lung cancer; 151 non-small cell lung cancer (NSCLC) and 19 small cell lung cancer (SCLC) were included. A higher proportion of never-smokers (54.1%) were observed, mostly presenting below the age of 60 yr. Most subjects were in stage IV and III at the time of diagnosis. More than 50 per cent of patients presented with late stage lung cancer even though the duration of symptoms is less than 2 months. The 30-month overall survival rates for smokers and never-smokers were 32 and 49 per cent, respectively. No significant differences were observed in 30 month survival based on age at presentation, gender and type of lung cancer. Cox proportional hazards model identified never-smokers and duration of symptoms less than 1 month as factors adversely affecting survival. Interpretation & conclusions: Our results showed that lung cancer in Indians involved younger subjects and associated with poorer survival as compared to other ethnic population. Studies on large sample need to be done to evaluate risk factors in lung cancer patients. PMID:23168702

  14. Shear bond strength of porcelain laminate veneers to enamel, dentine and enamel-dentine complex bonded with different adhesive luting systems.

    PubMed

    Öztürk, Elif; Bolay, Şükran; Hickel, Reinhard; Ilie, Nicoleta

    2013-02-01

    The aim of this study was to evaluate the shear bond strength of porcelain laminate veneers to 3 different surfaces by means of enamel, dentine, and enamel-dentine complex. One hundred thirty-five extracted human maxillary central teeth were used, and the teeth were randomly divided into 9 groups (n=15). The teeth were prepared with 3 different levels for bonding surfaces of enamel (E), dentine (D), and enamel-dentine complex (E-D). Porcelain discs (IPS e.max Press, Ivoclar Vivadent) of 2mm in thickness and 4mm in diameter were luted to the tooth surfaces by using 2 light-curing (RelyX Veneer [RV], 3M ESPE; Variolink Veneer [VV], Ivoclar Vivadent) and a dual-curing (Variolink II [V2], Ivoclar Vivadent) adhesive systems according to the manufacturers' instructions. Shear bond strength test was performed in a universal testing machine at 0.5mm/min until bonding failure. Failure modes were determined under a stereomicroscope, and fracture surfaces were evaluated with a scanning electron microscope. The data were statistically analysed (SPSS 17.0) (p=0.05). Group RV-D exhibited the lowest bond strength value (5.42±6.6MPa). There was statistically no difference among RV-D, V2-D (13.78±8.8MPa) and VV-D (13.84±6.2MPa) groups (p>0.05). Group VV-E exhibited the highest bond strength value (24.76±8.8MPa). The type of tooth structure affected the shear bond strength of the porcelain laminate veneers to the 3 different types of tooth structures (enamel, dentine, and enamel-dentine complex). When dentine exposure is necessary during preparation, enough sound enamel must be protected as much as possible to maintain a good bonding; to obtain maximum bond strength, preparation margins should be on sound enamel. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Bonded Radii and the Contraction of the Electron Density of the Oxygen Atom by Bonded Interactions

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

    Gibbs, Gerald V.; Ross, Nancy L.; Cox, David F.

    2013-02-21

    more electronegative M atoms. On the other hand, the ionic radii are in closer agreement with rb(M) for the more electropositive atoms. Notwithstanding that ionic radii are typically smaller than bonded radii, particularly for the more electronegative atoms, they have been used with considerable success in understanding and rationalizing problems and properties in crystal chemistry primarily because both ionic and crystal radii are highly correlated on a one-to-one basis with both the bonded radii and the associated M-O bond lengths. The lack of agreement between the effective ionic and crystal radii and the bonded radii for the more shared bonded interactions is ascribed to the progressive increase in the polarization of the O atom by the bonded atoms with a concomitant decrease in its radius, a factor that was neglected in the compilation of ionic and crystal radii for fluorides, oxides, sulfides and nitrides. This accounts for ionic radii for these materials being smaller than the bonded radii for the more electronegative atoms.« less

  16. Factors affecting medication-order processing time.

    PubMed

    Beaman, M A; Kotzan, J A

    1982-11-01

    The factors affecting medication-order processing time at one hospital were studied. The order processing time was determined by directly observing the time to process randomly selected new drug orders on all three work shifts during two one-week periods. An order could list more than one drug for an individual patient. The observer recorded the nature, location, and cost of the drugs ordered, as well as the time to process the order. The time and type of interruptions also were noted. The time to process a drug order was classified as six dependent variables: (1) total time, (2) work time, (3) check time, (4) waiting time I--time from arrival on the dumbwaiter until work was initiated, (5) waiting time II--time between completion of the work and initiation of checking, and (6) waiting time III--time after the check was completed until the order left on the dumbwaiter. The significant predictors of each of the six dependent variables were determined using stepwise multiple regression. The total time to process a prescription order was 58.33 +/- 48.72 minutes; the urgency status of the order was the only significant determinant of total time. Urgency status also significantly predicted the three waiting-time variables. Interruptions and the number of drugs on the order were significant determinants of work time and check time. Each telephone interruption increased the work time by 1.72 minutes. While the results of this study cannot be generalized to other institutions, pharmacy managers can use the method of determining factors that affect medication-order processing time to identify problem areas in their institutions.

  17. 30 CFR 581.33 - Bonds and bonding requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Bonds and bonding requirements. 581.33 Section 581.33 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE... title. Prior to the approval of a Delineation, Testing, or Mining Plan, the bond amount shall be...

  18. 30 CFR 281.33 - Bonds and bonding requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Bonds and bonding requirements. 281.33 Section 281.33 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF..., Testing, or Mining Plan, the bond amount shall be adjusted, if appropriate, to cover the operations and...

  19. 30 CFR 581.33 - Bonds and bonding requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Bonds and bonding requirements. 581.33 Section 581.33 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE... title. Prior to the approval of a Delineation, Testing, or Mining Plan, the bond amount shall be...

  20. 30 CFR 581.33 - Bonds and bonding requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Bonds and bonding requirements. 581.33 Section 581.33 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE... title. Prior to the approval of a Delineation, Testing, or Mining Plan, the bond amount shall be...

  1. Social-bond strength influences vocally mediated recruitment to mobbing

    PubMed Central

    2016-01-01

    Strong social bonds form between individuals in many group-living species, and these relationships can have important fitness benefits. When responding to vocalizations produced by groupmates, receivers are expected to adjust their behaviour depending on the nature of the bond they share with the signaller. Here we investigate whether the strength of the signaller–receiver social bond affects response to calls that attract others to help mob a predator. Using field-based playback experiments on a habituated population of wild dwarf mongooses (Helogale parvula), we first demonstrate that a particular vocalization given on detecting predatory snakes does act as a recruitment call; receivers were more likely to look, approach and engage in mobbing behaviour than in response to control close calls. We then show that individuals respond more strongly to these recruitment calls if they are from groupmates with whom they are more strongly bonded (those with whom they preferentially groom and forage). Our study, therefore, provides novel evidence about the anti-predator benefits of close bonds within social groups. PMID:27903776

  2. Social-bond strength influences vocally mediated recruitment to mobbing.

    PubMed

    Kern, Julie M; Radford, Andrew N

    2016-11-01

    Strong social bonds form between individuals in many group-living species, and these relationships can have important fitness benefits. When responding to vocalizations produced by groupmates, receivers are expected to adjust their behaviour depending on the nature of the bond they share with the signaller. Here we investigate whether the strength of the signaller-receiver social bond affects response to calls that attract others to help mob a predator. Using field-based playback experiments on a habituated population of wild dwarf mongooses (Helogale parvula), we first demonstrate that a particular vocalization given on detecting predatory snakes does act as a recruitment call; receivers were more likely to look, approach and engage in mobbing behaviour than in response to control close calls. We then show that individuals respond more strongly to these recruitment calls if they are from groupmates with whom they are more strongly bonded (those with whom they preferentially groom and forage). Our study, therefore, provides novel evidence about the anti-predator benefits of close bonds within social groups. © 2016 The Author(s).

  3. Hydroxide-catalyzed bonding

    NASA Technical Reports Server (NTRS)

    Gwo, Dz-Hung (Inventor)

    2003-01-01

    A method of bonding substrates by hydroxide-catalyzed hydration/dehydration involves applying a bonding material to at least one surface to be bonded, and placing the at least one surface sufficiently close to another surface such that a bonding interface is formed between them. A bonding material of the invention comprises a source of hydroxide ions, and may optionally include a silicate component, a particulate filling material, and a property-modifying component. Bonding methods of the invention reliably and reproducibly provide bonds which are strong and precise, and which may be tailored according to a wide range of possible applications. Possible applications for bonding materials of the invention include: forming composite materials, coating substrates, forming laminate structures, assembly of precision optical components, and preparing objects of defined geometry and composition. Bonding materials and methods of preparing the same are also disclosed.

  4. Bonding quality of contemporary dental cements to sandblasted esthetic crown copings.

    PubMed

    Abdelaziz, Khalid M; Al-Qahtani, Nasser M; Al-Shehri, Abdulrahman S; Abdelmoneam, Adel M

    2012-05-01

    To evaluate the shear bond strength of current luting cements to sandblasted crown-coping substrates. Specimens of nickel-chromium, pressable glass ceramic, and zirconia crown-coping substrates were sandblasted in three groups (n = 30 each) with 50 (group 1), 110 (group 2), and 250 μm (group 3) alumina particles at a pressure of 250 kPa. Cylinders of glass ionomer, universal resin, and self-adhesive resin cements were then built up on the sandblasted substrate surfaces of each group (n = 10). All bonded specimens were stressed to evaluate the cement-substrate shear bond strength. Both the mode and incidence of bond failure were also considered. No difference was noticed between all test groups in terms of cement-substrate bond strength. In comparison to self-adhesive type, the universal resin cement provided lower bond strengths to both metal and glass-ceramic substrates in group 1. The self-adhesive resin cement provided the highest bond strengths to the zirconia substrates in groups 2 and 3. The adhesive type of bond failure was common in the metal and zirconia substrates in all groups. Cement-substrate bonding quality is not affected by the size of sandblasting particles. Resin cements bond better to different coping substrates. Self-adhesive resin cement is the best choice to bond zirconia-based substrates. © 2011 Blackwell Publishing Asia Pty Ltd.

  5. Teaching the Factors Affecting Resistance Using Pencil Leads

    ERIC Educational Resources Information Center

    Küçüközer, Asuman

    2015-01-01

    The aim of this paper is to provide a way of teaching the factors that affect resistance using mechanical pencil leads and the brightness of the light given out by a light bulb connected to an electrical circuit. The resistance of a conductor is directly proportional to its length (L) and inversely proportional to its cross-sectional area (A).…

  6. Culture and affect: the factor structure of the affective style questionnaire and its relation with depression and anxiety among Japanese.

    PubMed

    Ito, Masaya; Hofmann, Stefan G

    2014-09-02

    Affective styles are assumed to be one of the underlying processes of depression and anxiety maintenance. However, little is known about the effect of depression and anxiety and the cultural influence of the factor structure. Here, we examined the cross-cultural validity of the Affective Style Questionnaire and its incremental validity for the influence on depression and anxiety. Affective Style Questionnaire was translated into Japanese using standard back-translation procedure. Japanese university students (N = 1,041) served as participants. Emotion Regulation Questionnaire, Acceptance and Action Questionnaire-II, Toronto Alexithymia Scale, Rumination and Reflection Questionnaire, Brief COPE, Self-Construal Scale, and Hospital Anxiety and Depression Scale were administered. Exploratory and confirmatory factor analyses showed that the Affective Style Questionnaire comprised four factors: Concealing, Adjusting, Holding and Tolerating (CFI = .92, TLI = .90, RMSEA = .07). The measure's convergent and discriminant validity was substantiated by its association with various emotion regulation measures. Regression analyses showed that negative influence of Adjusting, Holding, Reappraisal (β = -.17, -.19, -.30) and positive influence of Suppression (β = .23) were observed on depression. For anxiety, Adjusting and Reappraisal was negatively influenced (β = -.29, and -.18). Reliability and validity of the Affective Style Questionnaire was partly confirmed. Further study is needed to clarify the culturally dependent aspects of affective styles.

  7. Variations of the Hydrogen Bonding and of the Hydrogen Bonded Network in Ethanol-Water Mixtures on Cooling.

    PubMed

    Pothoczki, Szilvia; Pusztai, Laszlo; Bako, Imre

    2018-06-12

    Molecular dynamics computer simulations have been conducted for ethanol-water liquid mixtures in the water-rich side of the composition range, with 10, 20 and 30 mol % of the alcohol, at temperatures between room temperature and the experimental freezing point of the given mixture. All-atom type (OPLS) interatomic potentials have been assumed for ethanol, in combination with two kinds of rigid water models (SPC/E and TIP4P/2005). Both combinations have provided excellent reproductions of the experimental X-ray total structure factors at each temperature; this yielded a strong basis for further structural analyses. Beyond partial radial distribution functions, various descriptors of hydrogen bonded assemblies, as well as of the hydrogen bonded network have been determined. A clear tendency was observed towards that an increasing proportion of water molecules participate in hydrogen bonding with exactly 2 donor- and 2 acceptor sites as temperature decreases. Concerning larger assemblies held together by hydrogen bonding, the main focus was put on the properties of cyclic entities: it was found that, similarly to methanol-water mixtures, the number of hydrogen bonded rings has increased with lowering temperature. However, for ethanol-water mixtures the dominance of not the six-, but of the five-fold rings could be observed.

  8. Quantum finance Hamiltonian for coupon bond European and barrier options.

    PubMed

    Baaquie, Belal E

    2008-03-01

    Coupon bond European and barrier options are financial derivatives that can be analyzed in the Hamiltonian formulation of quantum finance. Forward interest rates are modeled as a two-dimensional quantum field theory and its Hamiltonian and state space is defined. European and barrier options are realized as transition amplitudes of the time integrated Hamiltonian operator. The double barrier option for a financial instrument is "knocked out" (terminated with zero value) if the price of the underlying instrument exceeds or falls below preset limits; the barrier option is realized by imposing boundary conditions on the eigenfunctions of the forward interest rates' Hamiltonian. The price of the European coupon bond option and the zero coupon bond barrier option are calculated. It is shown that, is general, the constraint function for a coupon bond barrier option can -- to a good approximation -- be linearized. A calculation using an overcomplete set of eigenfunctions yields an approximate price for the coupon bond barrier option, which is given in the form of an integral of a factor that results from the barrier condition times another factor that arises from the payoff function.

  9. Factors That Affect the Academic Success of Foreign Students at Cardinal Stritch University

    ERIC Educational Resources Information Center

    Annor, Peter

    2010-01-01

    There are limited studies in the literature on the factors that affect the academic success of foreign students in the United States. This ex post facto mixed method study investigated the factors that affect the academic success of foreign students at Cardinal Stitch University (CSU), a medium size, private university located in the Midwestern…

  10. Influence of metal bonding layer on strain transfer performance of FBG

    NASA Astrophysics Data System (ADS)

    Liu, Hao; Chen, Weimin; Zhang, Peng; Liu, Li; Shu, Yuejie; Wu, Jun

    2013-01-01

    Metal bonding layer seriously affects the strain transfer performance of Fiber Bragg Grating (FBG). Based on the mode of FBG strain transfer, the influence of the length, the thickness, Poisson's ratio, elasticity modulus of metal bonding layer on the strain transfer coefficient of FBG is analyzed by numerical simulation. FBG is packaged to steel wire using metal bonding technology of FBG. The tensile tests of different bonding lengths and elasticity modulus are carried out. The result shows the strain transfer coefficient of FBGs are 0.9848,0.962 and their average strain sensitivities are 1.076 pm/μɛ,1.099 pm/μɛ when the metal bonding layer is zinc, whose lengths are 15mm, 20mm, respectively. The strain transfer coefficient of FBG packaged by metal bonding layer raises 8.9 percent compared to epoxy glue package. The preliminary experimental results show that the strain transfer coefficient increases with the length of metal bonding layer, decreases with the thickness of metal bonding layer and the influence of Poisson's ratio can be ignored. The experiment result is general agreement with the analysis and provides guidance for metal package of FBG.

  11. Looking under the Bonnet: Factors Affecting Student Adoption of E-Learning Systems in Jordan

    ERIC Educational Resources Information Center

    Abbad, Muneer Mahmood; Morris, David; de Nahlik, Carmel

    2009-01-01

    The primary questions addressed in this paper are the following: what are the factors that affect students' adoption of an e-learning system and what are the relationships among these factors? This paper investigates and identifies some of the major factors affecting students' adoption of an e-learning system in a university in Jordan. E-learning…

  12. Sticker Bonding.

    ERIC Educational Resources Information Center

    Frazier, Laura Corbin

    2000-01-01

    Introduces a science activity on the bonding of chemical compounds. Assigns students the role of either a cation or anion and asks them to write the ions they may bond with. Assesses students' understanding of charge, bonding, and other concepts. (YDS)

  13. Institutional and Managerial Factors Affecting International Student Recruitment Management

    ERIC Educational Resources Information Center

    Ross, Mitchell; Heaney, Joo-Gim; Cooper, Maxine

    2007-01-01

    Purpose: The purpose of this paper is to investigate international student recruitment from an institutional perspective and to consider institutional factors that may affect recruitment. Design/methodology/approach: A qualitative study is undertaken in which education marketing practitioners are interviewed regarding aspects of international…

  14. Halogen bonding, chalcogen bonding, pnictogen bonding, tetrel bonding: origins, current status and discussion.

    PubMed

    Brammer, Lee

    2017-10-13

    The role of the closing lecture in a Faraday Discussion is to summarise the contributions made to the Discussion over the course of the meeting and in so doing capture the main themes that have arisen. This article is based upon my Closing Remarks Lecture at the 203 rd Faraday Discussion meeting on Halogen Bonding in Supramolecular and Solid State Chemistry, held in Ottawa, Canada, on 10-12 th July, 2017. The Discussion included papers on fundamentals and applications of halogen bonding in the solid state and solution phase. Analogous interactions involving main group elements outside group 17 were also examined. In the closing lecture and in this article these contributions have been grouped into the four themes: (a) fundamentals, (b) beyond the halogen bond, (c) characterisation, and (d) applications. The lecture and paper also include a short reflection on past work that has a bearing on the Discussion.

  15. Moisture effect on interfacial integrity of epoxy-bonded system: a hierarchical approach

    NASA Astrophysics Data System (ADS)

    Tam, Lik-ho; Lun Chow, Cheuk; Lau, Denvid

    2018-01-01

    The epoxy-bonded system has been widely used in various applications across different scale lengths. Prior investigations have indicated that the moisture-affected interfacial debonding is the major failure mode of such a system, but the fundamental mechanism remains unknown, such as the basis for the invasion of water molecules in the cross-linked epoxy and the epoxy-bonded interface. This prevents us from predicting the long-term performance of the epoxy-related applications under the effect of the moisture. Here, we use full atomistic models to investigate the response of the epoxy-bonded system towards the adhesion test, and provide a detailed analysis of the interfacial integrity under the moisture effect and the associated debonding mechanism. Molecular dynamics simulations show that water molecules affect the hierarchical structure of the epoxy-bonded system at the nanoscale by disrupting the film-substrate interaction and the molecular interaction within the epoxy, which leads to the detachment of the epoxy thin film, and the final interfacial debonding. The simulation results show good agreement with the experimental results of the epoxy-bonded system. Through identifying the relationship between the epoxy structure and the debonding mechanism at multiple scales, it is shown that the hierarchical structure of the epoxy-bonded system is crucial for the interfacial integrity. In particular, the available space of the epoxy-bonded system, which consists of various sizes ranging from the atomistic scale to the macroscale and is close to the interface facilitates the moisture accumulation, leading to a distinct interfacial debonding when compared to the dry scenario.

  16. Bonding resin thixotropy and viscosity influence on dentine bond strength.

    PubMed

    Niem, Thomas; Schmidt, Alexander; Wöstmann, Bernd

    2016-08-01

    To investigate the influence of bonding resin thixotropy and viscosity on dentine tubule penetration, blister formation and consequently on dentine bond strength as a function of air-blowing pressure (air-bp) intensity. Two HEMA-free, acetone-based, one-bottle self-etch adhesives with similar composition except disparate silica filler contents and different bonding resin viscosities were investigated. The high-filler-containing adhesive (G-Bond) featured a lower viscous bonding resin with inherent thixotropic resin (TR) properties compared to the low-filler-containing adhesive (iBond) exhibiting a higher viscous bonding resin with non-thixotropic resin (NTR) properties. Shear bond strength tests for each adhesive with low (1.5bar; 0.15MPa; n=16) and high (3.0bar; 0.30MPa; n=16) air-bp application were performed after specimen storage in distilled water (24h; 37.0±1.0°C). Results were analysed using a Student's t-test to identify statistically significant differences (p<0.05). Fracture surfaces of TR adhesive specimens were morphologically characterised by SEM. Statistically significant bond strength differences were obtained for the thixotropic resin adhesive (high-pressure: 24.6MPa, low-pressure: 9.6MPa). While high air-bp specimens provided SEM images revealing resin-plugged dentine tubules, resin tags and only marginally blister structures, low air-bp left copious droplets and open dentine tubules. In contrast, the non-thixotropic resin adhesive showed no significant bond strength differences (high-pressure: 9.3MPa, low-pressure: 7.6MPa). A pressure-dependent distinct influence of bonding resin thixotropy and viscosity on dentine bond strength has been demonstrated. Stronger adhesion with high air-bp application is explained by improved resin fluidity and facilitated resin penetration into dentine tubules. Filler particles used in adhesive systems may induce thixotropic effects in bonding resin layers, accounting for improved free-flowing resin properties. In

  17. Exploratory study of bed-sharing and maternal-infant bonding.

    PubMed

    Mitchell, Edwin A; Hutchison, B Lynne; Thompson, John Md; Wouldes, Trecia A

    2015-08-01

    Bed-sharing with an infant is controversial due to the increased risk of sudden unexpected death in infancy versus postulated benefits of the practice such as enhanced breastfeeding and maternal-infant bonding. This study evaluated the association between bed-sharing and maternal-infant bonding. Four hundred randomly selected mothers who had delivered in a large maternity unit in Auckland and whose infants were between the ages of 6 weeks and 4 months were sent a postal questionnaire asking about their bed-sharing practices last night, usually, and in the last 2 weeks. Included in the questionnaire were factors 1 and 2 questions from the Postpartum Bonding Questionnaire to assess maternal-infant bonding. Responders totalled 172 (43%), and infants were a mean age of 11 weeks. Fourteen per cent of infants slept in a bed-sharing situation last night, 8% usually, and 41% had slept with an adult in the last 2 weeks. Nine per cent of mothers scored above the cut-off for factor 1 for impaired maternal-infant bonding. Infants of these mothers were more likely to bed-share last night, usually, and in the last 2 weeks, and were less likely to use a pacifier and to breastfeed. Bed-sharing mothers scored more highly on individual questions relating to being annoyed or irritated by their baby. There is an inverse association between bed-sharing and maternal-infant bonding, which is contrary to the often expressed belief that bed-sharing enhances maternal-infant bonding. © 2015 The Authors. Journal of Paediatrics and Child Health © 2015 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  18. Effect of Saliva on the Tensile Bond Strength of Different Generation Adhesive Systems: An In-Vitro Study.

    PubMed

    Gupta, Nimisha; Tripathi, Abhay Mani; Saha, Sonali; Dhinsa, Kavita; Garg, Aarti

    2015-07-01

    Newer development of bonding agents have gained a better understanding of factors affecting adhesion of interface between composite and dentin surface to improve longevity of restorations. The present study evaluated the influence of salivary contamination on the tensile bond strength of different generation adhesive systems (two-step etch-and-rinse, two-step self-etch and one-step self-etch) during different bonding stages to dentin where isolation is not maintained. Superficial dentin surfaces of 90 extracted human molars were randomly divided into three study Groups (Group A: Two-step etch-and-rinse adhesive system; Group B: Two-step self-etch adhesive system and Group C: One-step self-etch adhesive system) according to the different generation of adhesives used. According to treatment conditions in different bonding steps, each Group was further divided into three Subgroups containing ten teeth in each. After adhesive application, resin composite blocks were built on dentin and light cured subsequently. The teeth were then stored in water for 24 hours before sending for testing of tensile bond strength by Universal Testing Machine. The collected data were then statistically analysed using one-way ANOVA and Tukey HSD test. One-step self-etch adhesive system revealed maximum mean tensile bond strength followed in descending order by Two-step self-etch adhesive system and Two-step etch-and-rinse adhesive system both in uncontaminated and saliva contaminated conditions respectively. Unlike One-step self-etch adhesive system, saliva contamination could reduce tensile bond strength of the two-step self-etch and two-step etch-and-rinse adhesive system. Furthermore, the step of bonding procedures and the type of adhesive seems to be effective on the bond strength of adhesives contaminated with saliva.

  19. Early maternal and paternal bonding, childhood physical abuse and adult psychopathic personality

    PubMed Central

    Gao, Y.; Raine, A.; Chan, F.; Venables, P. H.; Mednick, S. A.

    2013-01-01

    Background A significant gap in the literature on risk factors for psychopathy is the relative lack of research on parental bonding. Method This study examines the cross-sectional relationship between maternal and paternal bonding, childhood physical abuse and psychopathic personality at age 28 years in a community sample of 333 males and females. It also assesses prospectively whether children separated from their parents in the first 3 years of life are more likely to have a psychopathic-like personality 25 years later. Results Hierarchical regression analyses indicated that: (1) poor parental bonding (lack of maternal care and low paternal overprotection) and childhood physical abuse were both associated with a psychopathic personality; (2) parental bonding was significantly associated with psychopathic personality after taking into account sex, social adversity, ethnicity and abuse; (3) those separated from parents in the first 3 years of life were particularly characterized by low parental bonding and a psychopathic personality in adulthood; and (4) the deviant behavior factor of psychopathy was more related to lack of maternal care whereas the emotional detachment factor was related to both lack of maternal care and paternal overprotection. Conclusions Findings draw attention to the importance of different components of early bonding in relation to adult psychopathy, and may have potential implications for early intervention and prevention of psychopathy. PMID:20441692

  20. Longitudinal Associations Between Parental Bonding, Parenting Stress, and Executive Functioning in Toddlerhood.

    PubMed

    de Cock, Evi S A; Henrichs, Jens; Klimstra, Theo A; Janneke B M Maas, A; Vreeswijk, Charlotte M J M; Meeus, Wim H J; van Bakel, Hedwig J A

    2017-01-01

    Early executive functioning is an important predictor for future development of children's cognitive skills and behavioral outcomes. Parenting behavior has proven to be a key environmental determinant of child executive functioning. However, the association of parental affect and cognitions directed to the child with child executive functioning has been understudied. Therefore, in the present study we examine the associations between parental bonding (i.e., the affective tie from parent to child), parenting stress, and child executive functioning. At 26 weeks of pregnancy, and at 6 months and 24 months postpartum the quality of the maternal (N = 335) and paternal (N = 261) bond with the infant was assessed. At 24 months, postnatal parenting stress and child executive functioning were measured by means of parent-report questionnaires. Results indicated that for both mothers and fathers feelings of bonding negatively predicted experienced parenting stress over time. In addition, for both parents a negative indirect effect of bonding on child executive functioning problems was found via experienced parenting stress. These findings indicate the importance of monitoring parents who experience a low level and quality of early parent-child bonding, as this makes them vulnerable to parenting stress, consequently putting their children at risk for developing executive functioning problems.

  1. Psychological factors affecting medical condition: a new proposal for DSM-V.

    PubMed

    Fava, Giovanni A; Fabbri, Stefania; Sirri, Laura; Wise, Thomas N

    2007-01-01

    The DSM category of "psychological factors affecting medical condition" had virtually no impact on clinical practice. However, several clinically relevant psychosomatic syndromes have been described in the literature: disease phobia, persistent somatization, conversion symptoms, illness denial, demoralization, and irritable mood. These syndromes, in addition to the DSM definition of hypochondriasis, can yield clinical specification in the category of "psychological factors affecting medical condition" and eliminate the need for the highly criticized DSM classification of somatoform disorders. This new classification is supported by a growing body of research evidence and is in line with psychosomatic medicine as a recognized subspecialty.

  2. Demographic and obstetric factors affecting women's sexual functioning during pregnancy.

    PubMed

    Abouzari-Gazafroodi, Kobra; Najafi, Fatemeh; Kazemnejad, Ehsan; Rahnama, Parvin; Montazeri, Ali

    2015-08-19

    Sexual desire and frequency of sexual relationships during pregnancy remains challenging. This study aimed to assess factors that affect women's sexual functioning during pregnancy. This was a cross sectional study carried out at prenatal care clinics of public health services in Iran. An author-designed structured questionnaire including items on socio-demographic characteristics, obstetric history, the current pregnancy, and women's sexual functioning during pregnancy was used to collect data. The generalized linear model was performed in order to find out factors that affect women's sexual functioning during pregnancy. In all, 518 pregnant women participated in the study. The mean age of participants was 26.4 years (SD = 4.7). Overall 309 women (59.7%) scored less than mean on sexual functioning. The results obtained from generalized linear model demonstrated that that lower education, unwanted pregnancy, earlier stage of pregnancy, older age, and longer duration of marriage were the most important factors contributing to disturbed sexual functioning among couples. The findings suggest that sexual function during pregnancy might be disturbed due to several factors. Indeed issues on sexual relationship should be included as part of prenatal care and reproductive health programs for every woman.

  3. Picosecond laser bonding of highly dissimilar materials

    NASA Astrophysics Data System (ADS)

    Carter, Richard M.; Troughton, Michael; Chen, Jianyong; Elder, Ian; Thomson, Robert R.; Lamb, Robert A.; Esser, M. J. Daniel; Hand, Duncan P.

    2016-10-01

    We report on recent progress in developing an industrially relevant, robust technique to bond dissimilar materials through ultra-fast microwelding. This technique is based on the use of a 5.9ps, 400kHz Trumpf laser operating at 1030nm. Tight focusing of the laser radiation at, or around, the interface between two materials allows for simultaneous absorption in both. This absorption rapidly, and locally, heats the material forming plasma from both materials. With suitable surface preparation this plasma can be confined to the interface region where it mixes, cools and forms a weld between the two materials. The use of ps pulses results in a short interaction time. This enables a bond to form whilst limiting the heat affected zone (HAZ) to a region of only a few hundred micrometres across. This small scale allows for the bonding of materials with highly dissimilar thermal properties, and in particular coefficients of thermal expansion e.g. glass-metal bonding. We report on our results for a range of material combinations including, Al-Bk7, Al-SiO2 and Nd:YAG-AlSi. Emphasis will be laid on the technical requirements for bonding including the required surface preparation of the two materials and on the laser parameters required. The quality of the resultant bonds are characterized through shear force measurements (where strengths equal to and exceeding equivalent adhesives will be presented). The lifetime of the welds is also discussed, paying particular attention to the results of thermal cycling tests.

  4. Validation of the Malay Version of the Parental Bonding Instrument among Malaysian Youths Using Exploratory Factor Analysis.

    PubMed

    Muhammad, Noor Azimah; Shamsuddin, Khadijah; Omar, Khairani; Shah, Shamsul Azhar; Mohd Amin, Rahmah

    2014-01-01

    Parenting behaviour is culturally sensitive. The aims of this study were (1) to translate the Parental Bonding Instrument into Malay (PBI-M) and (2) to determine its factorial structure and validity among the Malaysian population. The PBI-M was generated from a standard translation process and comprehension testing. The validation study of the PBI-M was administered to 248 college students aged 18 to 22 years. Participants in the comprehension testing had difficulty understanding negative items. Five translated double negative items were replaced with five positive items with similar meanings. Exploratory factor analysis showed a three-factor model for the PBI-M with acceptable reliability. Four negative items (items 3, 4, 8, and 16) and item 19 were omitted from the final PBI-M list because of incorrect placement or low factor loading (< 0.32). Out of the final 20 items of the PBI-M, there were 10 items for the care factor, five items for the autonomy factor and five items for the overprotection factor. All the items loaded positively on their respective factors. The Malaysian population favoured positive items in answering questions. The PBI-M confirmed the three-factor model that consisted of care, autonomy and overprotection. The PBI-M is a valid and reliable instrument to assess the Malaysian parenting style. Confirmatory factor analysis may further support this finding. Malaysia, parenting, questionnaire, validity.

  5. Affect and Health Behavior Co-Occurrence: The Emerging Roles of Transdiagnostic Factors and Sociocultural Factors.

    PubMed

    Zvolensky, Michael J; Leventhal, Adam M

    2016-01-01

    The majority of scientific work addressing relations among affective states and health correlates has focused primarily on their co-occurrence and a limited range of health conditions. We have developed a Special Issue to highlight recent advances in this emerging field of work that addresses the nature and interplay between affective states and disorders, in terms of their impact and consequences from health status and behavior. This Special Issue is organized into three parts classified as (a) co-occurrence and interplay between (b) transdiagnostic factors and (c) sociocultural factors. It is hoped that this issue will (a) alert readers to the significance of this work at different levels of analysis, (b) illustrate the many domains currently being explored via innovative approaches, and (c) identify fecund areas for future systematic study. © The Author(s) 2016.

  6. Prevalence, pathophysiological mechanisms and factors affecting urolithiasis.

    PubMed

    Khan, Aslam

    2018-05-01

    The formation of urinary stone, urolithiasis, is one the oldest known disease affecting human throughout different civilizations and times. The exact pathophysiological mechanism of urolithiasis is not yet clear, as these calculi are of various types and too complex for simple understanding. A single theory cannot explain its formation; therefore, different theories are presented in various times for its explanation like free particle, fixed particle, Randall's plaque theory. In addition, various factors and components are identified that play an important role in the formation of these urinary calculi. In this review, composition of kidney stones, its prevalence/incidence, explanation of pathophysiological mechanisms and role of various factors; urinary pH, uric acid, parathyroid hormone, citrate, oxalate, calcium and macromolecules; osteopontin, matrix Gla protein, kidney injury molecules, urinary prothrombin fragment-1, Tamm-Horsfall protein, inter-α-inhibitors, have been discussed in detail.

  7. Effect of hydrostatic pressure on regional bond strengths of compomers to dentine.

    PubMed

    Zheng, L; Pereira, P N; Somphone, P; Nikaido, T; Tagami, J

    2000-09-01

    The aim of this study was to evaluate the effect of hydrostatic pressure on the regional bond strengths of compomers to dentine. Thirty freshly extracted molars were ground flat to expose the dentine and randomly divided into two groups for bonding: no hydrostatic pressure and hydrostatic pressure of 15cm H(2)O. Xeno CF, Dyract AP and F 2000 were applied to dentine surfaces pretreated by the respective bonding systems following the manufactures' instructions, and then restored with Clearfil AP-X. After 24h storage in water, the teeth were sectioned into 0.7-mm thick slabs and visually divided into three regional subgroups: the region communicating with the pulp through dentinal tubules (pulp horn); the region between the pulp horns (center); and the region between the pulp horn and DEJ (periphery). The specimens were trimmed to a cross-sectional area of 1mm(2) and subjected to the micro-tensile bond test. The data were analyzed by one- and three-way ANOVA, and Fisher's PLSD (p<0.05). There were no significant regional differences of bond strengths for all the compomers tested (p>0.05). However, hydrostatic pressure significantly decreased the bond strength of F 2000 to all regions (p<0.05), while the bond strength of Dyract AP significantly decreased only at the pulp horn region (p<0.05). On the other hand, the bond strengths of Xeno CF seemed not to be affected by hydrostatic pressure (p>0.05). For Dyract AP and F 2000, the fracture modes were affected by hydrostatic pressure, while, for Xeno CF, there were no significant differences between the fracture modes with non- or positive hydrostatic pressure. Simulated pulpal pressure of 15cm H(2)O had a greater influence on the bond strengths of compomers to dentine than did dentine regions. Therefore, when measuring the bond strengths of compomers to dentine under the simulated in vivo conditions, the wetness of the dentine surface, as well as the intrinsic properties of each material should be seriously considered.

  8. Bond strength of self-etch adhesives after saliva contamination at different application steps.

    PubMed

    Cobanoglu, N; Unlu, N; Ozer, F F; Blatz, M B

    2013-01-01

    This study evaluated and compared the effect of saliva contamination and possible decontamination methods on bond strengths of two self-etching adhesive systems (Clearfil SE Bond [CSE], Optibond Solo Plus SE [OSE]). Flat occlusal dentin surfaces were created on 180 extracted human molar teeth. The two bonding systems and corresponding composite resins (Clearfil AP-X, Kerr Point 4) were bonded to the dentin under six surface conditions (n=15/group): group 1 (control): primer/bonding/composite; group 2: saliva/drying/primer/bonding/composite; group 3: primer/saliva/rinsing/drying/primer/bonding/composite; group 4: primer/saliva/rinsing/drying/bonding/composite; group 5: primer/bonding (cured)/saliva/rinsing/drying/primer/bonding/composite; group 6: primer/bonding (cured)/saliva/removing contaminated layer with a bur/rinsing/drying/primer/bonding/composite. Shear bond strength was tested after specimens were stored in distilled water at 37°C for 24 hours. One-way analysis of variance and Tukey post hoc tests were used for statistical analyses. For CSE, groups 2, 3, and 4 and for OSE, groups 6, 2, and 4 showed significantly lower bond strengths than the control group (p<0.05). CSE groups 5 and 6 and OSE groups 3 and 5 revealed bond strengths similar to the control. When saliva contamination occurred after light polymerization of the bonding agent, repeating the bonding procedure recovered the bonding capacity of both self-etch adhesives. However, saliva contamination before or after primer application negatively affected their bond strength.

  9. Effects of different etching methods and bonding procedures on shear bond strength of orthodontic metal brackets applied to different CAD/CAM ceramic materials.

    PubMed

    Buyuk, S Kutalmış; Kucukekenci, Ahmet Serkan

    2018-03-01

    To investigate the shear bond strength (SBS) of orthodontic metal brackets applied to different types of ceramic surfaces treated with different etching procedures and bonding agents. Monolithic CAD/CAM ceramic specimens (N = 120; n = 40 each group) of feldspathic ceramic Vita Mark II, resin nanoceramic Lava Ultimate, and hybrid ceramic Vita Enamic were fabricated (14 × 12 × 3 mm). Ceramic specimens were separated into four subgroups (n = 10) according to type of surface treatment and bonding onto the ceramic surface. Within each group, four subgroups were prepared by phosphoric acid, hydrofluoric acid, Transbond XT primer, and Clearfill Ceramic primer. Mandibular central incisor metal brackets were bonded with light-cure composite. The SBS data were analyzed using three-way analysis of variance (ANOVA) and Tukey HSD tests. The highest SBS was found in the Vita Enamic group, which is a hybrid ceramic, etched with hydrofluoric acid and applied Transbond XT Adhesive primer (7.28 ± 2.49 MPa). The lowest SBS was found in the Lava Ultimate group, which is a resin nano-ceramic etched with hydrofluoric acid and applied Clearfill ceramic primer (2.20 ± 1.21 MPa). CAD/CAM material types and bonding procedures affected bond strength ( P < .05), but the etching procedure did not ( P > .05). The use of Transbond XT as a primer bonding agent resulted in higher SBS.

  10. [The bonding mechanisms of base metals for metal-ceramic crown microstructure analysis of bonding agent and gold bond between porcelain and base metals].

    PubMed

    Wang, C C; Hsu, C S

    1996-06-01

    The use of base metal alloys for porcelain fused to a metal crown and bridges has increased recently because of lower price, high hardness, high tensile strength and high elastic modulus. The addition of beryllium to base metal alloys increased fluidity and improved casting fitness. Beryllium also controlled surface oxidation and bonding strength. The bonding agent and gold bonding agent also affected the bonding strength between porcelain and metal alloys. Four commercially available ceramic base alloys were studied (two alloys contained beryllium element, another two did not). The purpose of this investigation was to study the microstructure between porcelain matrix, bonding agent and alloy matrix interfaces. A scanning electron micro-probe analyzer and energy dispersive X-ray spectroscopy (EDXS) were used to study the distribution of elements (Ni, Cr, Mo, Cu, O, Si, Sn, Al) in four base alloys. The following results were obtained: 1. The thickness of the oxidized layer of Rexillium III alloy and Unitbond alloy (contained beryllium) was thinner than Unibond alloy and Wiron 88 alloy (no beryllium). 2. The thickness of the oxidized layer of alloys in air (10 minutes and 30 minutes) was thinner in Unitbond (2.45 microns and 3.80 microns) and thicker in Wiron 88 (4.39 microns and 5.96 microns). 3. The thickness of the oxidized layer occurring for a duration of ten minutes (in vaccum) showed that the Rexillium III alloy was the thinnest (1.93 microns), and Wiron 88 alloy was the thickest (2.30 microns). But in thirty minutes (vacuum), Unitbond alloy was the thinnest (3.37 microns), and Wiron 88 alloy was the thickest (5.51 microns). 4. The intensity of Cr elements was increased obviously near the interface between Unitbond alloy, Wiron 88 alloy (no beryllium) and oxidized layer, but the intensity of Ni and Mo elements was slightly increased. The intensity of Cr element was not increased markedly between Rexillium III alloy, Unitbond alloy (beryllium) and oxidized

  11. Is the Effect of Postpartum Depression on Mother-Infant Bonding Universal?

    PubMed

    Badr, Lina Kurdahi; Ayvazian, Nelly; Lameh, Salma; Charafeddine, Lama

    2018-05-01

    Although the negative consequences of maternal depression on infants has been documented in several Western societies, similar studies have not been conducted in Middle-Eastern countries where cultural norms and traditions may differ. The main objective of this study was to determine the risk factors for postpartum depression (PPD) and its relationship to mother -infant bonding in a Lebanese population. One hundred and fifty participants were administered the Edinburgh Postpartum Depression Scale (EPDS), and the social support scale at 2-3 days postpartum. At 10-12 weeks mother-infant bonding using the Postpartum Bonding Questionnaire (PBQ) and depression using the Beck Inventory (BDI-II) were assessed during a telephone interview. The prevalence of depression was 19% with an average score of 10.9 ± 6.02 on the EPDS. At 10-12 weeks 2.7% of the whole sample was depressed with an average score of 18.60 ± 16.87 on the BDI-II. Risk factors of PPD on the EPDS were; history of alcohol use, complications during pregnancy, not a good marital relationship, baby admitted to an intensive care unit, history of depression and low social support. Risk factors for impaired bonding were age, history of depression, BDI-II scores above 20 and low social support. The multiple regression analysis found that impaired bonding was associated with older age, history of depression and low social support, which explained 39% of the variance, F = 7.12, p = 0.02. The prevalence of PPD was higher than previously reported at day 2-3 post-delivery, but lower at 10-12 weeks postpartum. Impaired mother- infant bonding was associated older mothers, history of depression, low social support and BDI-II scores above 20 which should alert practitioner to assessing these factors in post-partum mothers. Copyright © 2018. Published by Elsevier Inc.

  12. Factors that affect the development of nurses' competencies: a systematic review.

    PubMed

    Rizany, Ichsan; Hariyati, Rr Tutik Sri; Handayani, Hanny

    2018-02-01

    To investigate factors affecting the development of nursing competency based on a review of the literature. A systematic review was utilized. The articles were taken from the databases of Pro-Quest, ScienceDirect, SpringerLink, and Scopus. They were retrieved using the following keywords: nursing competence, nurse competencies and clinical competence. Twenty-one papers were selected. Competence development is a continuous process of improving knowledge, attitudes and skills, and is influenced by a myriad of factors. Six factors were identified that affected the development of nursing competence in our systematic review: (1) work experience, (2) type of nursing environment, (3) educational level achieved, (4) adherence to professionalism, (5) critical thinking, and (6) personal factors. Work experience and education were shown to significantly influence the development of competency of nurses. Nurse managers need to support staffing competence through ongoing education, mentoring-preceptorship training, and case-reflection-discussion teaching programs. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

  13. Mean bond-length variations in crystals for ions bonded to oxygen

    PubMed Central

    2017-01-01

    Variations in mean bond length are examined in oxide and oxysalt crystals for 55 cation configurations bonded to O2−. Stepwise multiple regression analysis shows that mean bond length is correlated to bond-length distortion in 42 ion configurations at the 95% confidence level, with a mean coefficient of determination (〈R 2〉) of 0.35. Previously published correlations between mean bond length and mean coordination number of the bonded anions are found not to be of general applicability to inorganic oxide and oxysalt structures. For two of 11 ions tested for the 95% confidence level, mean bond lengths predicted using a fixed radius for O2− are significantly more accurate as those predicted using an O2− radius dependent on coordination number, and are statistically identical otherwise. As a result, the currently accepted ionic radii for O2− in different coordinations are not justified by experimental data. Previously reported correlation between mean bond length and the mean electronegativity of the cations bonded to the oxygen atoms of the coordination polyhedron is shown to be statistically insignificant; similar results are obtained with regard to ionization energy. It is shown that a priori bond lengths calculated for many ion configurations in a single structure-type leads to a high correlation between a priori and observed mean bond lengths, but a priori bond lengths calculated for a single ion configuration in many different structure-types leads to negligible correlation between a priori and observed mean bond lengths. This indicates that structure type has a major effect on mean bond length, the magnitude of which goes beyond that of the other variables analyzed here.

  14. Predicting Trigger Bonds in Explosive Materials through Wiberg Bond Index Analysis.

    PubMed

    Harper, Lenora K; Shoaf, Ashley L; Bayse, Craig A

    2015-12-21

    Understanding the explosive decomposition pathways of high-energy-density materials (HEDMs) is important for developing compounds with improved properties. Rapid reaction rates make the detonation mechanisms of HEDMs difficult to understand, so computational tools are used to predict trigger bonds-weak bonds that break, leading to detonation. Wiberg bond indices (WBIs) have been used to compare bond densities in HEDMs to reference molecules to provide a relative scale for the bond strength to predict the activated bonds most likely to break to trigger an explosion. This analysis confirms that X-NO2 (X=N,C,O) bonds are trigger linkages in common HEDMs such as TNT, RDX and PETN, consistent with previous experimental and theoretical studies. Calculations on a small test set of substituted tetrazoles show that the assignment of the trigger bond depends upon the functionality of the material and that the relative weakening of the bond correlates with experimental impact sensitivities. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. The decision process used for hospital bond rating--and its implications.

    PubMed Central

    Cleverley, W O; Nutt, P C

    1984-01-01

    Investigation of the process of hospital bond rating related the ratings assigned by Moody's and Standard and Poors to indicators of hospital financial condition (such as debt per bed and peak debt coverage), institutional factors (including size, occupancy, and local market competition), indenture provisions (such as reserves), and contextual factors. The criteria used by Moody's and Standard and Poors to rate hospital bonds were revealed to be similar, but not identical. Criteria used in the bond rating process have several important implications: the rating approach provides strong financial incentives for increases in hospital size and complexity, for example, and hospitals that rely on extensive amounts of public financing appear to be penalized in the rating process. PMID:6500959

  16. Factors Affecting Recruitment into Child and Adolescent Psychiatry Training

    ERIC Educational Resources Information Center

    Shaw, Jon A.; Lewis, John E.; Katyal, Shalini

    2010-01-01

    Objective: The authors studied the factors affecting the recruitment into child and adolescent psychiatry training in the United States. Methods: Medical students (n = 154) and general and child and adolescent psychiatry residents (n = 111) completed a questionnaire to evaluate career choice in child psychiatry (n = 265). Results: Compared with…

  17. Effects of hydrogen bond on the melting point of azole explosives

    NASA Astrophysics Data System (ADS)

    Wang, Jian-Hua; Shen, Chen; Liu, Yu-Cun; Luo, Jin; Duan, Yingjie

    2018-07-01

    Melting point is an important index to determine whether an explosive can be a melt cast carrier. In this study, the relationship among the molecular structure, crystal structure, and melting point of explosives was investigated by using nitroazole compounds. Hydrogen bonds influence crystal packing modes in chemically understandable ways. Hydrogen bonds also affect the changes in entropy and enthalpy in balancing melting process. Hence, different types of hydrogen bonds in explosive crystal structures were compared when the relationship between the molecular structure and the melting point of nitroazole explosives were analyzed. The effects of methyl and amino groups on intermolecular hydrogen bonds were also compared. Results revealed that the methyl and amino groups connected on the N(1) of the heterocyclic compound can reduce the melting point of azole explosive. This finding is possible because methyl and amino groups destroy the intermolecular hydrogen bond of the heterocyclic compound.

  18. Elucidating bonding preferences in tetrakis(imido)uranate(VI) dianions

    NASA Astrophysics Data System (ADS)

    Anderson, Nickolas H.; Xie, Jing; Ray, Debmalya; Zeller, Matthias; Gagliardi, Laura; Bart, Suzanne C.

    2017-09-01

    Actinyl species, [AnO2]2+, are well-known derivatives of the f-block because of their natural occurrence and essential roles in the nuclear fuel cycle. Along with their nitrogen analogues, [An(NR)2]2+, actinyls are characterized by their two strong trans-An-element multiple bonds, a consequence of the inverse trans influence. We report that these robust bonds can be weakened significantly by increasing the number of multiple bonds to uranium, as demonstrated by a family of uranium(VI) dianions bearing four U-N multiple bonds, [M]2[U(NR)4] (M = Li, Na, K, Rb, Cs). Their geometry is dictated by cation coordination and sterics rather than by electronic factors. Multiple bond weakening by the addition of strong π donors has the potential for applications in the processing of high-valent actinyls, commonly found in environmental pollutants and spent nuclear fuels.

  19. A review of affecting factors on sexual satisfaction in women.

    PubMed

    Shahhosseini, Zohreh; Gardeshi, Zeinab Hamzeh; Pourasghar, Mehdi; Salehi, Fariba

    2014-12-01

    Sex is a complex, important and sensitive issue in human being and interwoven with the whole of human existence. Given the serious changes in attitude, function and behavior in sex, the need to address sexual function, especially sexual satisfaction, is felt completely. Sexual satisfaction has a very important role in creating marital satisfaction and any defect in sexual satisfaction is significantly associated with risky sexual behaviors, serious mental illness, social crimes and ultimately divorce. The aim of this study was to explore affecting factors on sexual satisfaction in women based on an overview in scientific database. In this narrative review the researchers searched MEDLINE database, Google Scholar and Science Direct as well as Persian database like Scientific Information Database with search terms of sexual satisfaction and sexual function, restricted to English/ Persian language, during the 20 years ago. Then those articles written by renowned experts were selected. In this regard, 57 articles have been reviewed, which 30 articles related to this research have been extracted. The findings were divided in to four categories including: Demographic factors, Pathophysiological factors, Psychological factors and Sociocultural factors. Sexuality, especially sexual intimacy is sophisticated and yet elegant affair that the other persons has different definitions and different functions. Discrepancies in the results of the studies show that analysis of factors affecting sexual satisfaction regardless of the women's' sociocultural context, religious beliefs, and personal attitudes is undoubtedly inefficient, unscientific and irrational.

  20. Assessment of psychometric properties of the Postpartum Bonding Questionnaire (PBQ) in Spanish mothers.

    PubMed

    Garcia-Esteve, Lluïsa; Torres, Anna; Lasheras, Gracia; Palacios-Hernández, Bruma; Farré-Sender, Borja; Subirà, Susana; Valdés, Manuel; Brockington, Ian Fraser

    2016-04-01

    The Postpartum Bonding Questionnaire (PBQ) was developed to assess mother-infant bonding disturbances in the postpartum period. The aim of this study was to examine the psychometric properties of the Spanish version of the PBQ in a sample of Spanish postpartum women. Eight hundred forty mothers were recruited in the postpartum visit (4-6 weeks after delivery): 513 from a gynecology unit (forming the general population sample) and 327 mothers from a perinatal psychiatry program (forming the clinical sample). All women were assessed by means of the Edinburgh Postnatal Depression Scale (EPDS) and the PBQ. Neither the original four-factor structure nor alternative structures (Reck et al. 2006; Wittkowski et al. 2010) were replicated by the confirmatory factor analyses. An exploratory factor analysis showed a four-factor solution. The Schmid-Leiman transformation found a general factor that accounted for 61% of the variance of the PBQ. Bonding impairment showed higher associations with depressive symptomatology in both samples. The Spanish version of the PBQ showed adequate psychometric properties for use with clinical and general populations of Spanish postpartum women. The results suggest that the PBQ could be summarized by a general factor and confirm the utility of the use of the total score for detecting bonding impairment.

  1. Bond Issues.

    ERIC Educational Resources Information Center

    Pollack, Rachel H.

    2000-01-01

    Notes trends toward increased borrowing by colleges and universities and offers guidelines for institutions that are considering issuing bonds to raise money for capital projects. Discussion covers advantages of using bond financing, how use of bonds impacts on traditional fund raising, other cautions and concerns, and some troubling aspects of…

  2. Factors affecting yearly and monthly visits to Taipei Zoo

    NASA Astrophysics Data System (ADS)

    Su, Ai-Tsen; Lin, Yann-Jou

    2018-02-01

    This study investigated factors affecting yearly and monthly numbers of visits to Taipei Zoo. Both linear and nonlinear regression models were used to estimate yearly visits. The results of both models showed that the "opening effect" and "animal star effect" had a significantly positive effect on yearly visits, while a SARS outbreak had a negative effect. The number of years had a significant influence on yearly visits. Results showed that the nonlinear model had better explanatory power and fitted the variations of visits better. Results of monthly model showed that monthly visits were significantly influenced by time fluctuations, weather conditions, and the animal star effect. Chinese New Year, summer vacation, numbers of holidays, and animal star exhibitions increased the number of monthly visits, while the number of days with temperatures at or below 15 °C, the number of days with temperatures at or above 30 °C, and the number of rainy days had significantly negative effects. Furthermore, the model of monthly visits showed that the animal star effect could last for over two quarters. The results of this study clarify the factors affecting visits to an outdoor recreation site and confirm the importance of meteorological factors to recreation use.

  3. A Qualitative Study of Factors Affecting Morale in Psychiatry Residency Training.

    PubMed

    Caravella, Rachel A; Robinson, Lee A; Wilets, Ilene; Weinberg, Michael; Cabaniss, Deborah L; Cutler, Janis L; Kymissis, Carisa; Arbuckle, Melissa R

    2016-10-01

    Resident morale is an important yet poorly understood aspect of the residency training experience. Despite implications for program quality, resident satisfaction, patient care, and recruitment, little is known about the variables influencing this complex phenomenon. This study sought to identify important factors affecting morale in psychiatry residency training. The authors conducted four semi-structured focus groups at a moderately sized, urban, psychiatry residency program during the 2013-2014 academic year. They used qualitative data analysis techniques, including grounded theory and content analysis, to identify key themes affecting resident morale across training levels. Twenty-seven residents participated in the focus groups with equal distribution across post-graduate years (PGY) 1-4. Five major conceptual categories affecting resident morale emerged: Sense of Community, Individual Motivators, Clinical Work, Feeling Cared For, and Trust in the Administration. Morale is an important topic in residency education. The qualitative results suggest that factors related to a Sense of Community and Individual Motivators generally enhanced resident morale whereas factors related to a lack of Feeling Cared For and Trust in the Administration tended to contribute to lower morale. The authors describe the possible interventions to promote stronger program morale suggested by these findings.

  4. Factors affecting the overcrowding in outpatient healthcare

    PubMed Central

    Bahadori, Mohammadkarim; Teymourzadeh, Ehsan; Ravangard, Ramin; Raadabadi, Mehdi

    2017-01-01

    Background: The expansion of outpatient services and the desire to provide more outpatient care than inpatient care create some problems such as the overcrowding in the outpatient clinics. Given the importance of overcrowding in the outpatient clinics, this qualitative study aimed to determine the factors influencing the overcrowding in the specialty and subspecialty clinic of a teaching hospital. Materials and Methods: This was a qualitative study conducted in the specialty and subspecialty clinic of a hospital using content analysis method in the period of January to March 2014. The study population was all managers and heads of the outpatient wards. The studied sample consisted of 22 managers of the clinic wards who were selected using the purposive sampling method. The required data was collected using semi-structured interviews. The collected data was analyzed using conventional content analysis and the MAXQDA 10.0 software. Results: Three themes were identified as the main factors affecting the overcrowding including the internal positive factors, internal negative factors, and external factors. Conclusions: Despite the efforts made to eliminate overcrowding, and reduce waiting times and increase access to the services for patients, the problem of overcrowding still has remained unresolved. In addition, the use of some strategies such as clarifying the working processes of the clinic for staff and patients and the relationships between the clinic and other wards especially emergency department, as well as using a simple triage system on the patients’ arrival at the clinic are recommended. PMID:28546986

  5. Recruitment and retention: factors that affect pericyte migration

    PubMed Central

    Aguilera, Kristina Y.

    2013-01-01

    Pericytes are critical for vascular morphogenesis and contribute to several pathologies, including cancer development and progression. The mechanisms governing pericyte migration and differentiation are complex and have not been fully established. Current literature suggests that platelet-derived growth factor/platelet-derived growth factor receptor-β, sphingosine 1-phosphate/endothelial differentiation gene-1, angiopoietin-1/tyrosine kinase with immunoglobulin-like and EGF-like domains 2, angiopoietin-2/tyros-ine kinase with immunoglobulin-like and EGF-like domains 2, transforming growth factor β/activin receptor-like kinase 1, transforming growth factor β/activin receptor-like kinase 5, Semaphorin-3A/Neuropilin, and matrix metalloproteinase activity regulate the recruitment of pericytes to nascent vessels. Interestingly, many of these pathways are directly affected by secreted protein acidic and rich in cysteine (SPARC). Here, we summarize the function of these factors in pericyte migration and discuss if and how SPARC might infuence these activities and thus provide an additional layer of control for the recruitment of vascular support cells. Additionally, the consequences of targeted inhibition of pericytes in tumors and the current understanding of pericyte recruitment in pathological environments are discussed. PMID:23912898

  6. Factors Affecting Role Stress and Burnout among School Counselors

    ERIC Educational Resources Information Center

    Willingham, Wendy Elizabeth

    2009-01-01

    The purpose of this study is to determine factors affecting role stress and burnout among practicing school counselors as measured by the Maslach Burnout Inventory-Educators Survey (MBI-ES) and the Role Conflict and Ambiguity Scale. The MBI-ES utilizes three subscales to measure burnout: emotional exhaustion, depersonalization, and personal…

  7. Factors affecting species distribution predictions: A simulation modeling experiment

    Treesearch

    Gordon C. Reese; Kenneth R. Wilson; Jennifer A. Hoeting; Curtis H. Flather

    2005-01-01

    Geospatial species sample data (e.g., records with location information from natural history museums or annual surveys) are rarely collected optimally, yet are increasingly used for decisions concerning our biological heritage. Using computer simulations, we examined factors that could affect the performance of autologistic regression (ALR) models that predict species...

  8. Motivational Factors Affecting Online Learning by Japanese MBA Students

    ERIC Educational Resources Information Center

    Kikuchi, Hisayo

    2006-01-01

    In Japan, Internet based learning is still at an early stage. However, adult learners in Japanese society expect the development of flexible e-learning programs. This case study examines motivational factors affecting online learning in a Japanese and Australian MBA program, using observations, interviews and a questionnaire survey. The data were…

  9. Analysis of extrinsic and intrinsic factors affecting event related desynchronization production.

    PubMed

    Takata, Yohei; Kondo, Toshiyuki; Saeki, Midori; Izawa, Jun; Takeda, Kotaro; Otaka, Yohei; It, Koji

    2012-01-01

    Recently there has been an increase in the number of stroke patients with motor paralysis. Appropriate re-afferent sensory feedback synchronized with a voluntary motor intention would be effective for promoting neural plasticity in the stroke rehabilitation. Therefore, BCI technology is considered to be a promising approach in the neuro-rehabilitation. To estimate human motor intention, an event-related desynchronization (ERD), a feature of electroencephalogram (EEG) evoked by motor execution or motor imagery is usually used. However, there exists various factors that affect ERD production, and its neural mechanism is still an open question. As a preliminary stage, we evaluate mutual effects of intrinsic (voluntary motor imagery) and extrinsic (visual and somatosensory stimuli) factors on the ERD production. Experimental results indicate that these three factors are not always additively interacting with each other and affecting the ERD production.

  10. New strategies in the assessment of psychological factors affecting medical conditions.

    PubMed

    Sirri, Laura; Fabbri, Stefania; Fava, Giovanni A; Sonino, Nicoletta

    2007-12-01

    In this article, we examine research that may lead to a better assessment of psychological factors affecting medical conditions. We performed a review of the psychosomatic literature using both Medline and manual searches. We selected papers that were judged to be relevant to new strategies of assessment, with particular reference to the use of the Diagnostic Criteria for Psychosomatic Research. We assessed 8 areas concerned with the assessment of psychological factors in the setting of medical disease: hypochondriasis, disease phobia, persistent somatization, conversion symptoms, illness denial, demoralization, irritable mood, and Type A behavior. A new subclassification of the Diagnostic and Statistical Manual of Mental Disorders (5th ed. [DSM-V]; not yet published) category of psychological factors affecting physical conditions appears to be feasible and may provide the clinician with better tools for identifying psychological distress.

  11. Multifactorial analysis of factors affecting recurrence of stroke in Japan.

    PubMed

    Omori, Toyonori; Kawagoe, Masahiro; Moriyama, Michiko; Yasuda, Takeshi; Ito, Yasuhiro; Hyakuta, Takeshi; Nagatsuka, Kazuyuki; Matsumoto, Masayasu

    2015-03-01

    Data on factors affecting stroke recurrence are relatively limited. The authors examined potential factors affecting stroke recurrence, retrospectively. The study participants were 1087 patients who were admitted to stroke centers suffering from first-ever ischemic stroke and returned questionnaires with usable information after discharge. The authors analyzed the association between clinical parameters of the patients and their prognosis. Recurrence rate of during an average of 2 years after discharge was 21.3%, and there were differences among stroke subtypes. It was found that the disability level of the patients after discharge correlated well with the level at discharge (r s = 0.66). Multivariate logistic regression analysis of the data shows that modified Rankin Scale score, National Institute of Health Stroke Scale score, gender, age, and family history had statistically significant impacts on stroke recurrence, and the impact was different depending on subtypes. These findings suggest that aggressive and persistent health education for poststroke patients and management of risk factors are essential to reduce stroke recurrence. © 2012 APJPH.

  12. Mathematics Performance and the Role Played by Affective and Background Factors

    ERIC Educational Resources Information Center

    Grootenboer, Peter; Hemmings, Brian

    2007-01-01

    In this article, we report on a study examining those factors which contribute to the mathematics performance of a sample of children aged between 8 and 13 years. The study was designed specifically to consider the potency of a number of mathematical affective factors, as well as background characteristics (viz., gender, ethnicity, and…

  13. Factors Affecting Career Decision Making of Mexican and Mexican-American Students.

    ERIC Educational Resources Information Center

    Newlon, Betty J.; Borboa, Roman

    The purpose of this research was to identify the self-reported factors affecting the career decision making of Mexican and Mexican-American students. It was hypothesized that the factor clusters would differ between the two sample populations, Mexican and Mexican-American. It was also hypothesized that these clusters would differ from six clusters…

  14. Industry Training: The Factors that Affect Demand. Discussion Paper.

    ERIC Educational Resources Information Center

    Smith, A.; Roberts, P.; Noble, C.; Hayton, G.; Thorne, E.

    A study was conducted in Australia, to determine the factors that affect demand for job training. The study consisted of 30 detailed industry case studies, an industry analysis, and a literature review. Each case study examined current training practices, training decision making in the business, and the determinants of training for the…

  15. An Analysis of Factors Affecting Community College Students' Expectations on E-Learning

    ERIC Educational Resources Information Center

    Kilic-Cakmak, Ebru; Karatas, Sercin; Ocak, Mehmet Akif

    2009-01-01

    There are many factors that affect the e-learning process. Instructor, assessment and evaluation, communication, and technical support are among the leading factors. It is obvious that these factors influence the effectiveness of e-learning and may be related to different expectations of e-learners. Therefore, this study focuses on examining the…

  16. Synthesis and energetics of gold nanoclusters tailored by interfacial bonding structure

    NASA Astrophysics Data System (ADS)

    Tang, Zhenghua

    In addition to the well known quantum confinement effects resulted from size and shape, interfacial bond structure is another factor, affecting the properties of the nanomaterial that is rarely studied. Inspired by the "Au-S-Au" staple motif discovered from the crystal structure of monothiol protected Au102 nanocluster (Science, 2007, 318, 430), dithiol molecules (e.g. 1, 2-dithiol, 1, 4-dithiol, etc.) with molecular structural constraint have been employed to create dithiolate protected clusters or mixed monothiolate and dithiolate protected clusters. The structure and properties of the Au clusters are expected to change due to two effects: The entropy gain of dithiol over monothiol protection and the constraint to the formation of the thiol bridging motif. DMPS (1, 2-dithiol molecule) stabilized clusters with characteristic absorption bands have been obtained, and characterized by multiple techniques. Monolayer reaction on gold core surface between the monothiol tiopronin and dithiol DMPS has been performed, and the mechanism has been probed. Mixed phenylethanethiolate and durene-dithiolate (1, 4-dithiol molecule) protected Au130 clusters with rich electrochemical features have been created, and the optical and electrochemical energetics have been successfully correlated based on core and core-ligand energy states. Furthermore, the impact of 1, 4-dithiolate-Au bonding on the near infrared luminescence has been studied. INDEX WORDS: Au MPCs, Staple motif, DMPS, Au DTCs, Au4, Tiopronin, Monolayer reaction, Durene-DT, Au MTCs, Au130, Optical energetic, Electrochemistry, Near infrared luminescence, 1, 4-Dithiolate-Au bonding.

  17. Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors

    PubMed Central

    Tatarinova, Tatiana; Dien Bard, Jennifer; Cohen, Irit

    2015-01-01

    Proteins of the same functional family (for example, kinases) may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content) tend to have longer genes than species with low GC3 content. PMID:26114113

  18. Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors.

    PubMed

    Tatarinova, Tatiana; Salih, Bilal; Dien Bard, Jennifer; Cohen, Irit; Bolshoy, Alexander

    2015-01-01

    Proteins of the same functional family (for example, kinases) may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content) tend to have longer genes than species with low GC3 content.

  19. Hydrogen bonding strength of diblock copolymers affects the self-assembled structures with octa-functionalized phenol POSS nanoparticles.

    PubMed

    Lu, Yi-Syuan; Yu, Chia-Yu; Lin, Yung-Chih; Kuo, Shiao-Wei

    2016-02-28

    In this study, the influence of the functional groups by the diblock copolymers of poly(styrene-b-4-vinylpyridine) (PS-b-P4VP), poly(styrene-b-2-vinylpyridine) (PS-b-P2VP), and poly(styrene-b-methyl methacrylate) (PS-b-PMMA) on their blends with octa-functionalized phenol polyhedral oligomeric silsesquioxane (OP-POSS) nanoparticles (NPs) was investigated. The relative hydrogen bonding strengths in these blends follow the order PS-b-P4VP/OP-POSS > PS-b-P2VP/OP-POSS > PS-b-PMMA/OP-POSS based on the Kwei equation from differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopic analyses. Small-angle X-ray scattering and transmission electron microscopic analyses show that the morphologies of the self-assembly structures are strongly dependent on the hydrogen bonding strength at relatively higher OP-POSS content. The PS-b-P4VP/OP-POSS hybrid complex system with the strongest hydrogen bonds shows the order-order transition from lamellae to cylinders and finally to body-centered cubic spheres upon increasing OP-POSS content. However, PS-b-P2VP/OP-POSS and PS-b-PMMA/OP-POSS hybrid complex systems, having relatively weaker hydrogen bonds, transformed from lamellae to cylinder structures at lower OP-POSS content (<50 wt%), but formed disordered structures at relatively high OP-POSS contents (>50 wt%).

  20. A noncontacting scanning photoelectron emission technique for bonding surface cleanliness inspection

    NASA Technical Reports Server (NTRS)

    Gause, Raymond L.

    1989-01-01

    Molecular contamination of bonding surfaces can drastically affect the bond strength that can be achieved and therefore the structural integrity and reliability of the bonded part. The presence of thin contaminant films on bonding surfaces can result from inadequate or incomplete cleaning methods, from oxide growth during the time between cleaning (such as grit blasting) and bonding, or from failure to properly protect cleaned surfaces from oils, greases, fingerprints, release agents, or deposition of facility airborne molecules generated by adjacent manufacturing or processing operations. Required cleanliness levels for desired bond performance can be determined by testing to correlate bond strength with contaminant type and quantity, thereby establishing the degree of contamination that can be tolerated based on the strength that is needed. Once the maximum acceptable contaminant level is defined, a method is needed to quantitatively measure the contaminant level on the bonding surface prior to bonding to verify that the surface meets the established cleanliness requirement. A photoelectron emission technique for the nondestructive inspection of various bonding surfaces, both metallic and nonmetallic, to provide quantitative data on residual contaminant levels is described. The technique can be used to scan surfaces at speeds of at least 30 ft/min using a servo system to maintain required sensor to surface spacing. The fundamental operation of the photoelectron emission sensor system is explained and the automated scanning system and computer data acquisition hardware and software are described.

  1. A Study of the Technological, Instructional, and Motivational Factors Affecting PHR Certification Exam Outcomes

    ERIC Educational Resources Information Center

    Bonner, David M.

    2012-01-01

    Although previous studies have considered the factors affecting other certification exam outcomes, they have not examined those that are related to performance on the Professional in Human Resources (PHR) exam. In response to that need, this study specifically investigates technology and training factors that affect self-efficacy and self-set…

  2. Bond characteristics of reinforcing steel embedded in geopolymer concrete

    NASA Astrophysics Data System (ADS)

    Kathirvel, Parthiban; Thangavelu, Manju; Gopalan, Rashmi; Raja Mohan Kaliyaperumal, Saravana

    2017-07-01

    The force transferring between reinforcing steel and the surrounding concrete in reinforced concrete is influenced by several factors. Whereas, the study on bond behaviour of geopolymer concrete (GPC) is lagging. In this paper, an experimental attempt has been made to evaluate the geopolymer concrete bond with reinforcing steel of different diameter and embedded length using standard pull out test. The geopolymer concrete is made of ground granulated blast furnace slag (GGBFS) as geopolymer source material (GSM). The tests were conducted to evaluate the development of bond between steel and concrete of grade M40 and M50 with 12 and 16 mm diameter reinforcing steel for geopolymer and cement concrete mixes and to develop a relation between bond strength and compressive strength. From the experimental results, it has been observed that the bond strength of the geopolymer concrete mixes was more compared to the cement concrete mixes and increases with the reduction in the diameter of the bar.

  3. [Factors affecting residual stones after percutaneous nephrolithotomy in patients with renal calculus].

    PubMed

    Qiao, Mingzhou; Zhang, Haifang; Zhou, Chenlong

    2015-11-24

    To explore the factors affecting the residual stones after percutaneous nephrolithotomy (PCNL) in patients with renal calculus. A retrospective analysis was performed for 1 200 patients who were affected by renal calculus and treated with PCNL between Jan 2008 and May 2014 in People's Hospital of Anyang City. Among those patients, 16 were diagnosed as bilateral renal stone and had two successive operations. The size, location and number of stones, previous history of surgery, the degree of hydronephrosis, urinary infection were included in the univariate analysis. Significant factors in univariate analysis were included in the multivariate analysis to determine factors affecting stone residual. A total of 385 cases developed stone residual after surgery. The overall residual rate was 31.7%. In univariate analysis, renal pelvis combined with caliceal calculus (P=0.006), stone size larger than 4 cm (P=0.005), stone number more than 4 (P=0.002), the amount of bleeding more than 200 ml (P=0.025), operation time longer than 120 minutes (P=0.028) were associated with an increased rate of stone residual. When subjected to the Cox multivariate analysis, the independent risk factors for residual stones were renal pelvis combined with caliceal calculus (P=0.049), stone size larger than 4 cm (P=0.038) and stone number more than 4 (P=0.018). Factors affecting the incidence of residual stones after PCNL are the size, location and number of stones. Larger size stone and the presence of renal pelvis combined with caliceal calculus are significantly associated with residual stones. Nevertheless, stone number less than 4 indicates an increased stone clearance rate.

  4. Aspects of bonding between resin luting cements and glass ceramic materials.

    PubMed

    Tian, Tian; Tsoi, James Kit-Hon; Matinlinna, Jukka P; Burrow, Michael F

    2014-07-01

    The bonding interface of glass ceramics and resin luting cements plays an important role in the long-term durability of ceramic restorations. The purpose of this systematic review is to discuss the various factors involved with the bond between glass ceramics and resin luting cements. An electronic Pubmed, Medline and Embase search was conducted to obtain laboratory studies on resin-ceramic bonding published in English and Chinese between 1972 and 2012. Eighty-three articles were included in this review. Various factors that have a possible impact on the bond between glass ceramics and resin cements were discussed, including ceramic type, ceramic crystal structure, resin luting cements, light curing, surface treatments, and laboratory test methodology. Resin-ceramic bonding has been improved substantially in the past few years. Hydrofluoric acid (HF) etching followed by silanizaiton has become the most widely accepted surface treatment for glass ceramics. However, further studies need to be undertaken to improve surface preparations without HF because of its toxicity. Laboratory test methods are also required to better simulate the actual oral environment for more clinically compatible testing. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  5. Validation of the Malay Version of the Parental Bonding Instrument among Malaysian Youths Using Exploratory Factor Analysis

    PubMed Central

    MUHAMMAD, Noor Azimah; SHAMSUDDIN, Khadijah; OMAR, Khairani; SHAH, Shamsul Azhar; MOHD AMIN, Rahmah

    2014-01-01

    Background: Parenting behaviour is culturally sensitive. The aims of this study were (1) to translate the Parental Bonding Instrument into Malay (PBI-M) and (2) to determine its factorial structure and validity among the Malaysian population. Methods: The PBI-M was generated from a standard translation process and comprehension testing. The validation study of the PBI-M was administered to 248 college students aged 18 to 22 years. Results: Participants in the comprehension testing had difficulty understanding negative items. Five translated double negative items were replaced with five positive items with similar meanings. Exploratory factor analysis showed a three-factor model for the PBI-M with acceptable reliability. Four negative items (items 3, 4, 8, and 16) and item 19 were omitted from the final PBI-M list because of incorrect placement or low factor loading (< 0.32). Out of the final 20 items of the PBI-M, there were 10 items for the care factor, five items for the autonomy factor and five items for the overprotection factor. All the items loaded positively on their respective factors. Conclusion: The Malaysian population favoured positive items in answering questions. The PBI-M confirmed the three-factor model that consisted of care, autonomy and overprotection. The PBI-M is a valid and reliable instrument to assess the Malaysian parenting style. Confirmatory factor analysis may further support this finding. Keywords: Malaysia, parenting, questionnaire, validity PMID:25977634

  6. Interface bonding of SA508-3 steel under deformation and high temperature diffusion

    NASA Astrophysics Data System (ADS)

    Xu, Bin; Shao, Chunjuan; Sun, Mingyue

    2018-05-01

    There are mainly two parameters affecting high temperature interface bonding: deformation and diffusion. To study these two parameters, interface bonding of SA508-3 bainitic steel at 1100°C are simulated by gleeble3500 thermal simulator. The results show that interface of SA508-3 steel can be bonded under deformation and high temperature. For a specimen pressed at 1100°C without further high temperature diffusion, a reduction ratio of 30% can make the interface begun to bond, but the interface is still part of the grain boundary and small grains exist near the interface. When reduction ratio reaches 50%, the interface can be completely bonded and the microstructure near the interface is the same as that of the base material. When deformation is small, long time diffusion can also help the interface bonding. The results show that when the diffusion time is long enough, the interface under small deformation can also be bonded. For a specimen holding for 24h at 1100°C, only 13% reduction ratio is enough for interface bonding.

  7. Repositioning identity in conceptualizations human-place bonding

    Treesearch

    James D. Absher

    2010-01-01

    In this investigation, we adapted identity theory (references) to reassess a conceptualization of place attachment – an attitudinal construct used by environmental psychologists to describe people‘s bonding to the physical landscape. Past work has conceptualized the construct in terms of three components; cognitive, affective and conative elements. Based on the tents...

  8. Factors affecting decision-making of patients choosing acupuncture in a public hospital.

    PubMed

    Sayampanathan, Andrew Arjun; Koh, Thean Howe Bryan; Kong, Keng He; Low, Yin Peng

    2015-11-01

    With increasing evidence to support its practice, acupuncture has been integrated within many hospitals around the world. The purpose of this study is to understand the factors affecting decision making of patients as they select acupuncture treatment for their medical conditions and symptoms within a public hospital. A qualitative study consisting of in depth interviews with 14 patients was conducted. All patients attended an acupuncture clinic within a public hospital. Data collected was analysed via thematic analysis. Four main factor groups affecting decision making of patients were identified- factors affecting the level and value of patient-centric care, the confidence and trust patients place within the acupuncture service, the presence of collaborative efforts between acupuncturists and Western medicine practitioners, and the knowledge, culture and belief society has regarding the role of acupuncture and Western medicine. All participants interviewed had more than one factor group present as enablers toward their eventual selection of acupuncture for ailment management. It was also noted that although the majority of participants had sufficient knowledge regarding acupuncture, there were a select few who had misperceptions or no knowledge regarding certain aspects of acupuncture. There may be certain patterns in the way patients choose to utilise acupuncture services in public hospitals. Further studies should also be carried out in other public hospitals to analyse the factor groups identified further.

  9. Factors that Affect Poverty Areas in North Sumatera Using Discriminant Analysis

    NASA Astrophysics Data System (ADS)

    Nasution, D. H.; Bangun, P.; Sitepu, H. R.

    2018-04-01

    In Indonesia, especially North Sumatera, the problem of poverty is one of the fundamental problems that become the focus of government both central and local government. Although the poverty rate decreased but the fact is there are many people who are poor. Poverty happens covers several aspects such as education, health, demographics, and also structural and cultural. This research will discuss about several factors such as population density, Unemployment Rate, GDP per capita ADHK, ADHB GDP per capita, economic growth and life expectancy that affect poverty in Indonesia. To determine the factors that most influence and differentiate the level of poverty of the Regency/City North Sumatra used discriminant analysis method. Discriminant analysis is one multivariate analysis technique are used to classify the data into a group based on the dependent variable and independent variable. Using discriminant analysis, it is evident that the factor affecting poverty is Unemployment Rate.

  10. Effects of surface preparation on the long-term durability of adhesively bonded composite joints

    NASA Astrophysics Data System (ADS)

    Bardis, Jason Dante

    The long-term durability of adhesively bonded composite joints is critical to modern aircraft structures, which are increasingly adopting bonding as an alternative option to mechanical fastening. The effects of the surface preparation of the adherends are critical, affecting initial strength, long-term durability, fracture toughness, and failure modes of bonded joints. In this study, several potential factors are evaluated, with focus on the following: (1) Effects of possible chemical contamination from release fabrics, release films, and peel plies during adherend cure. (2) Chemical and mechanical effects of abrasion on the fracture toughness and failure mode. (3) Characterization of paste and film adhesives. There are several standard test methods used to evaluate specimen fracture, but the majority concentrate on bonded metals and interlaminar composite fracture. Testing concentrated on mode I tests; a custom double cantilever beam specimen was devised and utilized, and two forms of a wedge crack test (traveling and static) were also used. Additionally, single lap shear tests were run to contrast the mode I tests. Non-destructive testing included X-ray photography of crack fronts, energy dispersive spectroscopy and X-ray photoelectron spectroscopy surface chemistry analyses, and scanning electron microscope imaging of prepared surfaces. All mode I test methods tended to be in agreement in the ranking of different surface preparation methods. Test results revealed that release agents deposited on adherend surfaces during their cure cycle prevented proper adhesion. While mechanical abrasion did improve their fracture toughness and lower their contamination greatly, the test values did not reach the levels of samples that were not contaminated before bonding, and the interfacial modes of failure did not always change to desirable modes.

  11. Municipal Bond Insurance Might Enhance Your Next School Bond.

    ERIC Educational Resources Information Center

    Shapiro, Eric J.

    1989-01-01

    School systems with a rating of "A" or lower can save money by insuring their bonds because, in almost every instance, the reduced borrowing cost more than offsets the bond insurance premium. Included is a list compiled by Donna Harrington-Lueker of the four major players in the bond insurance field and elements to consider in choosing…

  12. Factors Other than GFR Affecting Serum Cystatin C Levels

    PubMed Central

    Stevens, Lesley A; Schmid, Christopher H.; Greene, Tom; Li, Liang; Beck, Gerald J; Joffe, Marshall; Froissart, Marc; Kusek, John; Zhang, Yaping (Lucy); Coresh, Josef; Levey, Andrew S

    2015-01-01

    Cystatin C is gaining acceptance as an endogenous filtration marker. Factors other than glomerular filtration rate (GFR) that affect the serum level have not been carefully studied. In a cross-sectional analysis of a pooled dataset of participants from clinical trials and a clinical population with chronic kidney disease (N=3418), we related serum levels of cystatin C and creatinine to clinical and biochemical variables after adjustment for GFR using errors-in-variables models to account for GFR measurement error. GFR was measured as urinary clearance of 125I-iothalamate and 15Cr-EDTA. Cystatin C was assayed at a single laboratory and creatinine was standardized to reference methods. Mean (SD) creatinine and cystatin C were 2.1 (1.1) mg/dL and 1.8 (0.8) mg/L, respectively. After adjustment for GFR, cystatin C was 4.3% lower for every 20 years of age, 9.2% lower for female sex but only 1.9% lower in blacks. Diabetes was associated with 8.5% higher levels of cystatin C and 3.9% lower levels of creatinine. Higher C-reactive protein and white blood cell count and lower serum albumin were associated with higher levels of cystatin C and lower levels of creatinine. Adjustment for age, sex and race had a greater effect on association of factors with creatinine than cystatin C. In conclusion, cystatin C is affected by factors other than GFR. Clinicians should consider these factors when interpreting the serum levels or GFR estimates from cystatin C. PMID:19119287

  13. Repositioning identity in conceptualizations of human-place bonding

    Treesearch

    Gerard T. Kyle; Jinhee Jun; James D. Absher

    2014-01-01

    In this investigation, we adapted identity theory to reassess a conceptualization of place attachment—conceived herein as an attitudinal construct used by environmental psychologists to describe people's bonding to the physical landscape. Past work has conceptualized the construct in terms of three components: cognitive, affective, and conative elements...

  14. Comparative evaluation of shear bond strength of metallic brackets bonded with two different bonding agents under dry conditions and with saliva contamination.

    PubMed

    Khanehmasjedi, Mashallah; Naseri, Mohammad Ali; Khanehmasjedi, Samaneh; Basir, Leila

    2017-02-01

    This study compared the shear bond strength of metallic brackets bonded with Single Bond and Assure bonding agents under dry and saliva-contamination conditions. Sixty sound premolar teeth were selected, and stainless-steel brackets were bonded on enamel surfaces with Single Bond and Assure bonding agents under dry condition or with saliva contamination. Shear bond strength values of brackets were measured in a universal testing machine. The adhesive remnant index scores were determined after debonding of the brackets under a stereomicroscope. One-way analysis of variance (ANOVA) was used to analyze bond strength. Two-by-two comparisons were made with post hoc Tukey tests (p<0.001). Frequencies of adhesive remnant index scores were analyzed by Kruskal-Wallis test. Bond strength values of brackets to tooth structure were 9.29±8.56 MPa and 21.25±8.93 MPa with the use of Assure resin bonding agent under saliva-contamination and dry conditions, respectively. These values were 10.13±6.69 MPa and 14.09±6.6 MPa, respectively, under the same conditions with the use of Single Bond adhesive. Contamination with saliva resulted in a significant decrease in the bond strength of brackets to tooth structure with the application of Assure adhesive resin (p<0.001). There were no significant differences in the adhesive remnant index scores between the study groups. Application of Single Bond and Assure bonding agents resulted in adequate bond strength of brackets to tooth structures. Contamination with saliva significantly decreased the bond strength of Assure bonding agent compared with dry conditions. Copyright © 2016. Published by Elsevier Taiwan LLC.

  15. Validating YouTube Factors Affecting Learning Performance

    NASA Astrophysics Data System (ADS)

    Pratama, Yoga; Hartanto, Rudy; Suning Kusumawardani, Sri

    2018-03-01

    YouTube is often used as a companion medium or a learning supplement. One of the educational places that often uses is Jogja Audio School (JAS) which focuses on music production education. Music production is a difficult material to learn, especially at the audio mastering. With tutorial contents from YouTube, students find it easier to learn and understand audio mastering and improved their learning performance. This study aims to validate the role of YouTube as a medium of learning in improving student’s learning performance by looking at the factors that affect student learning performance. The sample involves 100 respondents from JAS at audio mastering level. The results showed that student learning performance increases seen from factors that have a significant influence of motivation, instructional content, and YouTube usefulness. Overall findings suggest that YouTube has a important role to student learning performance in music production education and as an innovative and efficient learning medium.

  16. Beyond Negative Pain-Related Psychological Factors: Resilience Is Related to Lower Pain Affect in Healthy Adults.

    PubMed

    Hemington, Kasey S; Cheng, Joshua C; Bosma, Rachael L; Rogachov, Anton; Kim, Junseok A; Davis, Karen D

    2017-09-01

    Resilience, a characteristic that enhances adaptation in response to stressful events, is a positive psychological factor that can predict and modulate health outcomes. However, resilience is rarely considered in pain research. Conversely, negative psychological factors (eg, anxiety, depression) are known to be related to the affective dimension of pain. It is critical to understand all potential psychological drivers of pain affect, a prominent component of chronic pain. We tested the hypothesis that higher resilience is associated with lower pain affect, above and beyond the predictive value of negative psychological factors. Healthy adults underwent psychophysical testing to acquire ratings of heat pain intensity and unpleasantness and completed the Resilience Scale, the State-Trait Anxiety Inventory (trait form), Beck Depression Inventory, Pain Catastrophizing Scale, and the Pain Vigilance and Attention Questionnaire. Multiple regression modeling (n = 68) showed resilience to be a negatively associated with pain affect (unpleasantness). Furthermore, in individuals with higher anxiety scores, resilience was protective against higher pain affect. This highlights the importance of resilience, a positive psychological factor, in the affective dimension of pain. This study is the first to assess a positive psychological factor and experimental pain affect, and has the potential to improve prediction of and treatment strategies for clinical pain. We report that resilience, a positive psychological factor, interacts with anxiety and is associated with heat pain affect (unpleasantness) in healthy individuals. Resilience may provide predictive value of chronic pain affect and treatment outcomes, and could be a target for behavioral therapy. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.

  17. A study of the factors affecting the range of airplanes

    NASA Technical Reports Server (NTRS)

    Biermann, David

    1937-01-01

    A study was made of the most important factors affecting the range of airplanes. Numerical examples are given showing the effects of different variables on the range of a two-engine airplane. The takeoff problems of long-range airplanes are analyzed.

  18. An Empirically Derived Taxonomy of Factors Affecting Physicians' Willingness to Disclose Medical Errors

    PubMed Central

    Kaldjian, Lauris C; Jones, Elizabeth W; Rosenthal, Gary E; Tripp-Reimer, Toni; Hillis, Stephen L

    2006-01-01

    BACKGROUND Physician disclosure of medical errors to institutions, patients, and colleagues is important for patient safety, patient care, and professional education. However, the variables that may facilitate or impede disclosure are diverse and lack conceptual organization. OBJECTIVE To develop an empirically derived, comprehensive taxonomy of factors that affects voluntary disclosure of errors by physicians. DESIGN A mixed-methods study using qualitative data collection (structured literature search and exploratory focus groups), quantitative data transformation (sorting and hierarchical cluster analysis), and validation procedures (confirmatory focus groups and expert review). RESULTS Full-text review of 316 articles identified 91 impeding or facilitating factors affecting physicians' willingness to disclose errors. Exploratory focus groups identified an additional 27 factors. Sorting and hierarchical cluster analysis organized factors into 8 domains. Confirmatory focus groups and expert review relocated 6 factors, removed 2 factors, and modified 4 domain names. The final taxonomy contained 4 domains of facilitating factors (responsibility to patient, responsibility to self, responsibility to profession, responsibility to community), and 4 domains of impeding factors (attitudinal barriers, uncertainties, helplessness, fears and anxieties). CONCLUSIONS A taxonomy of facilitating and impeding factors provides a conceptual framework for a complex field of variables that affects physicians' willingness to disclose errors to institutions, patients, and colleagues. This taxonomy can be used to guide the design of studies to measure the impact of different factors on disclosure, to assist in the design of error-reporting systems, and to inform educational interventions to promote the disclosure of errors to patients. PMID:16918739

  19. Simultaneous bond degradation and bond formation during phenol-formaldehyde curing with wood

    Treesearch

    Daniel J. Yelle; John Ralph

    2016-01-01

    Bonding of wood using phenol–formaldehyde adhesive develops highly durable bonds. Phenol– formaldehyde is believed to form primary bonds with wood cell wall polymers (e.g., lignin). However, it is unclear how this adhesive interacts and bonds to lignin. Through wood solubilisation methodologies, earlywood and latewood bonded assemblies were characterized using two-...

  20. Effect of Pd Surface Roughness on the Bonding Process and High Temperature Reliability of Au Ball Bonds

    NASA Astrophysics Data System (ADS)

    Huang, Y.; Kim, H. J.; McCracken, M.; Viswanathan, G.; Pon, F.; Mayer, M.; Zhou, Y. N.

    2011-06-01

    A 0.3- μm-thick electrolytic Pd layer was plated on 1 μm of electroless Ni on 1 mm-thick polished and roughened Cu substrates with roughness values ( R a) of 0.08 μm and 0.5 μm, respectively. The rough substrates were produced with sand-blasting. Au wire bonding on the Ni/Pd surface was optimized, and the electrical reliability was investigated under a high temperature storage test (HTST) during 800 h at 250°C by measuring the ball bond contact resistance, R c. The average value of R c of optimized ball bonds on the rough substrate was 1.96 mΩ which was about 40.0% higher than that on the smooth substrate. The initial bondability increased for the rougher surface, so that only half of the original ultrasonic level was required, but the reliability was not affected by surface roughness. For both substrate types, HTST caused bond healing, reducing the average R c by about 21% and 27%, respectively. Au diffusion into the Pd layer was observed in scanning transmission electron microscopy/ energy dispersive spectroscopy (STEM-EDS) line-scan analysis after HTST. It is considered that diffusion of Au or interdiffusion between Au and Pd can provide chemically strong bonding during HTST. This is supported by the R c decrease measured as the aging time increased. Cu migration was indicated in the STEM-EDS analysis, but its effect on reliability can be ignored. Au and Pd tend to form a complete solid solution at the interface and can provide reliable interconnection for high temperature (250°C) applications.

  1. Factors Affecting Teen Involvement in Pennsylvania 4-H Programming

    ERIC Educational Resources Information Center

    Gill, Bart E.; Ewing, John C.; Bruce, Jacklyn A.

    2010-01-01

    The study reported here determined the factors that affect teen involvement in 4-H programming. The design of the study was descriptive and correlational in nature. Using a purposive sampling procedure, a survey questionnaire was distributed to all (N=214) 4-H members attending the 4-H State Leadership Conference. The major findings of the study…

  2. [Factors affecting the quality of cardiopulmonary resuscitation in inpatient units: perception of nurses].

    PubMed

    Citolino, Clairton Marcos Filho; Santos, Eduesley Santana; Silva, Rita de Cassia Gengo E; Nogueira, Lilia de Souza

    2015-12-01

    To identify, in the perception of nurses, the factors that affect the quality of cardiopulmonary resuscitation (CPR) in adult inpatient units, and investigate the influence of both work shifts and professional experience length of time in the perception of these factors. A descriptive, exploratory study conducted at a hospital specialized in cardiology and pneumology with the application of a questionnaire to 49 nurses working in inpatient units. The majority of nurses reported that the high number of professionals in the scenario (75.5%), the lack of harmony (77.6%) or stress of any member of staff (67.3%), lack of material and/or equipment failure (57.1%), lack of familiarity with the emergency trolleys (98.0%) and presence of family members at the beginning of the cardiopulmonary arrest assistance (57.1%) are factors that adversely affect the quality of care provided during CPR. Professional experience length of time and the shift of nurses did not influence the perception of these factors. The identification of factors that affect the quality of CPR in the perception of nurses serves as parameter to implement improvements and training of the staff working in inpatient units.

  3. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

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

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  4. Psychological Factor Affecting English Speaking Performance for the English Learners in Indonesia

    ERIC Educational Resources Information Center

    Haidara, Youssouf

    2016-01-01

    In every learning situation or environment, human psychology plays a significant role. English speaking is a language skill that is highly affected by human psychology. This research aimed at describing the psychological factor that affects negatively the English speaking performance for the English learners in Indonesia. A descriptive qualitative…

  5. The Key Factors Affecting Students' Individual Interest in School Science Lessons

    ERIC Educational Resources Information Center

    Cheung, Derek

    2018-01-01

    Individual interest in school science lessons can be defined as a relatively stable and enduring personal emotion comprising affective and behavioural reactions to events in the regular science lessons at school. Little research has compared the importance of different factors affecting students' individual interest in school science lessons. The…

  6. Theoretical and Experimental Evaluation of the Bond Strength Under Peeling Loads

    NASA Technical Reports Server (NTRS)

    Nayeb-Hashemi, Hamid; Jawad, Oussama Cherkaoui

    1997-01-01

    Reliable applications of adhesively bonded joints require understanding of the stress distribution along the bond-line and the stresses that are responsible for the joint failure. To properly evaluate factors affecting peel strength, effects of defects such as voids on the stress distribution in the overlap region must be understood. In this work, the peel stress distribution in a single lap joint is derived using a strength of materials approach. The bonded joint is modeled as Euler-Bernoulli beams, bonded together with an adhesive. which is modeled as an elastic foundation which can resist both peel and shear stresses. It is found that for certain adhesive and adherend geometries and properties, a central void with the size up to 50 percent of the overlap length has negligible effect on the peak peel and shear stresses. To verify the solutions obtained from the model, the problem is solved again by using the finite element method and by treating the adherends and the adhesive as elastic materials. It is found that the model used in the analysis not only predicts the correct trend for the peel stress distribution but also gives rather surprisingly close results to that of the finite element analysis. It is also found that both shear and peel stresses can be responsible for the joint performance and when a void is introduced, both of these stresses can contribute to the joint failure as the void size increases. Acoustic emission (AE) activities of aluminum-adhesive-aluminum specimens with different void sizes were monitored. The AE ringdown counts and energy were very sensitive and decreased significantly with the void size. It was observed that the AE events were shifting towards the edge of the overlap where the maximum peeling and shearing stresses were occurring as the void size increased.

  7. Sulfide bonded atomic radii

    NASA Astrophysics Data System (ADS)

    Gibbs, G. V.; Ross, N. L.; Cox, D. F.

    2017-09-01

    The bonded radius, r b(S), of the S atom, calculated for first- and second-row non-transition metal sulfide crystals and third-row transition metal sulfide molecules and crystals indicates that the radius of the sulfur atom is not fixed as traditionally assumed, but that it decreases systematically along the bond paths of the bonded atoms with decreasing bond length as observed in an earlier study of the bonded radius of the oxygen atom. When bonded to non-transition metal atoms, r b(S) decreases systematically with decreasing bond length from 1.68 Å when the S atom is bonded to the electropositive VINa atom to 1.25 Å when bonded to the more electronegative IVP atom. In the case of transition metal atoms, rb(S) likewise decreases with decreasing bond length from 1.82 Å when bonded to Cu and to 1.12 Å when bonded to Fe. As r b(S) is not fixed at a given value but varies substantially depending on the bond length and the field strength of the bonded atoms, it is apparent that sets of crystal and atomic sulfide atomic radii based on an assumed fixed radius for the sulfur atom are satisfactory in that they reproduce bond lengths, on the one hand, whereas on the other, they are unsatisfactory in that they fail to define the actual sizes of the bonded atoms determined in terms of the minima in the electron density between the atoms. As such, we urge that the crystal chemistry and the properties of sulfides be studied in terms of the bond lengths determined by adding the radii of either the atomic and crystal radii of the atoms but not in terms of existing sets of crystal and atomic radii. After all, the bond lengths were used to determine the radii that were experimentally determined, whereas the individual radii were determined on the basis of an assumed radius for the sulfur atom.

  8. Affective changes during the postpartum period: Influences of genetic and experiential factors.

    PubMed

    Agrati, Daniella; Lonstein, Joseph S

    2016-01-01

    This article is part of a Special Issue "Parental Care". The postpartum period involves some truly transformational changes in females' socioemotional behaviors. For most female laboratory rodents and women, these changes include an improvement in their affective state, which has positive consequences for their ability to sensitively care for their offspring. There is heterogeneity among females in the likelihood of this positive affective change, though, and some women experience elevated anxiety or depression (or in rodents anxiety- or depression-related behaviors) after giving birth. We aim to contribute to the understanding of this heterogeneity in maternal affectivity by reviewing selected components of the scientific literatures on laboratory rodents and humans examining how mothers' physical contact with her infants, genetics, history of anxiety and depression and early-life and recent-life experiences contribute to individual differences in postpartum affective states. These studies together indicate that multiple biological and environmental factors beyond female maternal state shape affective responses during the postpartum period, and probably do so in an interactive manner. Furthermore, the similar capacity of some of these factors to modulate anxiety and depression in human and rodent mothers suggests cross-species conservation of mechanisms regulating postpartum affectivity. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Factors Affecting Soil Microbial Community Structure in Tomato Cropping Systems

    USDA-ARS?s Scientific Manuscript database

    Soil and rhizosphere microbial communities in agroecosystems may be affected by soil, climate, plant species, and management. We identified some of the most important factors controlling microbial biomass and community structure in an agroecosystem utilizing tomato plants with the following nine tre...

  10. 27 CFR 26.70 - New or superseding bonds.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false New or superseding bonds. 26.70 Section 26.70 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU..., be required in any other contingency affecting the validity or impairing the efficiency of an...

  11. 27 CFR 26.70 - New or superseding bonds.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false New or superseding bonds. 26.70 Section 26.70 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU..., be required in any other contingency affecting the validity or impairing the efficiency of an...

  12. Halogen Bonding versus Hydrogen Bonding: A Molecular Orbital Perspective

    PubMed Central

    Wolters, Lando P; Bickelhaupt, F Matthias

    2012-01-01

    We have carried out extensive computational analyses of the structure and bonding mechanism in trihalides DX⋅⋅⋅A− and the analogous hydrogen-bonded complexes DH⋅⋅⋅A− (D, X, A=F, Cl, Br, I) using relativistic density functional theory (DFT) at zeroth-order regular approximation ZORA-BP86/TZ2P. One purpose was to obtain a set of consistent data from which reliable trends in structure and stability can be inferred over a large range of systems. The main objective was to achieve a detailed understanding of the nature of halogen bonds, how they resemble, and also how they differ from, the better understood hydrogen bonds. Thus, we present an accurate physical model of the halogen bond based on quantitative Kohn–Sham molecular orbital (MO) theory, energy decomposition analyses (EDA) and Voronoi deformation density (VDD) analyses of the charge distribution. It appears that the halogen bond in DX⋅⋅⋅A− arises not only from classical electrostatic attraction but also receives substantial stabilization from HOMO–LUMO interactions between the lone pair of A− and the σ* orbital of D–X. PMID:24551497

  13. Factors affecting the reproductive success of dominant male meerkats.

    PubMed

    Spong, Göran F; Hodge, Sarah J; Young, Andrew J; Clutton-Brock, Tim H

    2008-05-01

    Identifying traits that affect the reproductive success of individuals is fundamental for our understanding of evolutionary processes. In cooperative breeders, a dominant male typically restricts mating access to the dominant female for extended periods, resulting in pronounced variation in reproductive success among males. This may result in strong selection for traits that increase the likelihood of dominance acquisition, dominance retention and reproductive rates while dominant. However, despite considerable research on reproductive skew, few studies have explored the factors that influence these three processes among males in cooperative species. Here we use genetic, behavioural and demographic data to investigate the factors affecting reproductive success in dominant male meerkats (Suricata suricatta). Our data show that dominant males sire the majority of all offspring surviving to 1 year. A male's likelihood of becoming dominant is strongly influenced by age, but not by weight. Tenure length and reproductive rate, both important components of dominant male reproductive success, are largely affected by group size and composition, rather than individual traits. Dominant males in large groups have longer tenures, but after this effect is controlled, male tenure length also correlates negatively to the number of adult females in the group. Male reproductive rate also declines as the number of intra- and extra-group competitors increases. As the time spent in the dominant position and reproductive rate while dominant explain > 80% of the total variance in reproductive success, group composition thus has major implications for male reproductive success.

  14. Knowing What Matters: An Expanded Study of School Bond Elections in Michigan, 1998-2006

    ERIC Educational Resources Information Center

    Bowers, Alex J.; Metzger, Scott Alan; Militello, Matthew

    2010-01-01

    This study investigates what factors are associated with the likelihood of passing school facility construction bonds by local district election. It uses statewide data from Michigan, 1998-2006, to examine the outcome of 789 bond elections in terms of the following ten variables: amount of the bond request; district enrollment; district locale;…

  15. Exposure to Bordetella pertussis adenylate cyclase toxin affects integrin-mediated adhesion and mechanics in alveolar epithelial cells.

    PubMed

    Angely, Christelle; Nguyen, Ngoc-Minh; Andre Dias, Sofia; Planus, Emmanuelle; Pelle, Gabriel; Louis, Bruno; Filoche, Marcel; Chenal, Alexandre; Ladant, Daniel; Isabey, Daniel

    2017-08-01

    The adenylate cyclase (CyaA) toxin is a major virulent factor of Bordetella pertussis, the causative agent of whooping cough. CyaA toxin is able to invade eukaryotic cells where it produces high levels of cyclic adenosine monophosphate (cAMP) affecting cellular physiology. Whether CyaA toxin can modulate cell matrix adhesion and mechanics of infected cells remains largely unknown. In this study, we use a recently proposed multiple bond force spectroscopy (MFS) with an atomic force microscope to assess the early phase of cell adhesion (maximal detachment and local rupture forces) and cell rigidity (Young's modulus) in alveolar epithelial cells (A549) for toxin exposure <1 h. At 30 min of exposure, CyaA toxin has a minimal effect on cell viability (>95%) at CyaA concentration of 0.5 nM, but a significant effect (≈81%) at 10 nM. MFS performed on A549 for three different concentrations (0.5, 5 and 10 nM) demonstrates that CyaA toxin significantly affects both cell adhesion (detachment forces are decreased) and cell mechanics (Young's modulus is increased). CyaA toxin (at 0.5 nM) assessed at three indentation/retraction speeds (2, 5 and 10 μm/s) significantly affects global detachment forces, local rupture events and Young modulus compared with control conditions, while an enzymatically inactive variant CyaAE5 has no effect. These results reveal the loading rate dependence of the multiple bonds newly formed between the cell and integrin-specific coated probe as well as the individual bond kinetics which are only slightly affected by the patho-physiological dose of CyaA toxin. Finally, theory of multiple bond force rupture enables us to deduce the bond number N which is reduced by a factor of 2 upon CyaA exposure (N ≈ 6 versus N ≈ 12 in control conditions). MFS measurements demonstrate that adhesion and mechanical properties of A549 are deeply affected by exposure to the CyaA toxin but not to an enzymatically inactive variant. This indicates that the

  16. Bonding thermoplastic polymers

    DOEpatents

    Wallow, Thomas I [Fremont, CA; Hunter, Marion C [Livermore, CA; Krafcik, Karen Lee [Livermore, CA; Morales, Alfredo M [Livermore, CA; Simmons, Blake A [San Francisco, CA; Domeier, Linda A [Danville, CA

    2008-06-24

    We demonstrate a new method for joining patterned thermoplastic parts into layered structures. The method takes advantage of case-II permeant diffusion to generate dimensionally controlled, activated bonding layers at the surfaces being joined. It is capable of producing bonds characterized by cohesive failure while preserving the fidelity of patterned features in the bonding surfaces. This approach is uniquely suited to production of microfluidic multilayer structures, as it allows the bond-forming interface between plastic parts to be precisely manipulated at micrometer length scales. The bond enhancing procedure is easily integrated in standard process flows and requires no specialized equipment.

  17. Factors affecting the employability in people with epilepsy.

    PubMed

    Wo, Monica Chen Mun; Lim, Kheng Seang; Choo, Wan Yuen; Tan, Chong Tin

    2016-12-01

    People with epilepsy (PWE) are negatively prejudiced in their ability to work. This study aimed to examine demographic, clinical and psychological factors associated with employability in PWE. This study recruited epilepsy patients from a neurology clinic in Malaysia. Employability was measured using employment ratio, with a ratio ≥90% (ER90) classified as high employability. Basic demographic data such as age, gender, marital status, religion, education level and household income was collected. Clinical measures consisted of age of seizure onset, seizure frequency, type of epilepsy, aura, polytherapy, nocturnal seizures and seizure control. Psychological measures included Work Self-Determination Index (WSDI), Rosenberg Self-Esteem Scale (SES), and Multidimensional Scale of Perceived Social Support (MSPSS). Of 146 PWE, 64.4% had high employability. The participants were predominantly female (52%), Chinese (50.7%), single (50%), having tertiary education (55.5%) and focal epilepsy (72.6%). Clinically, only type of epilepsy was significantly correlated to employability of PWE. Employability of PWE was associated with ability to work (indicated by education level, work performance affected by seizures, ability to travel independently and ability to cope with stress at work) and family overprotection. The high employability group was found to have lower self-perceived stigma (ESS), higher self-determined motivation (WSDI), self-esteem (SES) and perceived social support (MSPSS), than the low employability group. Logistic regression analysis showed that tertiary education level (AOR 3.42, CI: 1.46-8.00), higher self-determination (WSDI, AOR 1.09, CI: 1.012-1.17), lower family overprotection (AOR 0.76, CI: 0.61-0.95), and generalised epilepsy (AOR 4.17, CI: 1.37-12.70) were significant predictors for higher employability in PWE. Ability to work (education level), clinical factor (type of epilepsy) and psychological factor (self-determined motivation and family

  18. Adhesive bonding of wood materials

    Treesearch

    Charles B. Vick

    1999-01-01

    Adhesive bonding of wood components has played an essential role in the development and growth of the forest products industry and has been a key factor in the efficient utilization of our timber resource. The largest use of adhesives is in the construction industry. By far, the largest amounts of adhesives are used to manufacture building materials, such as plywood,...

  19. 29 CFR 2580.412-19 - Term of the bond, discovery period, other bond clauses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SECURITY ACT OF 1974 TEMPORARY BONDING RULES General Bond Rules § 2580.412-19 Term of the bond, discovery... 29 Labor 9 2010-07-01 2010-07-01 false Term of the bond, discovery period, other bond clauses... new bond must be obtained each year. There is nothing in the Act that prohibits a bond for a term...

  20. Personal Factors that Affect the Satisfaction of Female Patients Undergoing Esthetic Suture after Typical Thyroidectomy.

    PubMed

    Kim, Hyo Young; Kim, Jung Won; Park, Jin Hyung; Kim, Jung Hun; Han, Yea Sik

    2013-07-01

    In esthetic surgery, understanding the factors that influence patient satisfaction is important for successful practice. We hypothesize that the factors that influence patient satisfaction include not only aesthetic and functional outcomes, but also personal factors such as the level of familiarity with factors affecting wound healing and expectations regarding aesthetic outcome. One hundred patients who underwent esthetic closure after thyroidectomy were included in this study. In order to evaluate the individual characteristics of the patients, a preoperative survey was administered to the patients. We estimated the patient satisfaction six months postoperatively and assessed the aesthetic and functional outcomes using the Patient and Observer Scar Assessment Scale. According to the results of correlation analysis, level of familiarity with wound healing factors had a positive correlation with satisfaction. High expectations, pain, itching, and high observer scale score had negative correlations with satisfaction. The factors that were correlated with satisfaction were included in the multiple regression analysis. Level of familiarity with wound healing factors was found to have a positive relationship with satisfaction, while itching and observer scale were found to have a negative relationship with satisfaction. After excluding 10 patients who had hypertrophic scars, only level of familiarity with wound healing factors and expectations affected satisfaction. The level of familiarity with factors affecting wound healing and expectations were found to independently affect satisfaction. Improving patients' level of familiarity with wound healing factors and reducing their expectations by providing suitable preoperative education has the potential to improve patient satisfaction.

  1. Arsenic in Drinking Water in Bangladesh: Factors Affecting Child Health

    PubMed Central

    Aziz, Sonia N.; Aziz, Khwaja M. S.; Boyle, Kevin J.

    2014-01-01

    The focus of this paper is to present an empirical model of factors affecting child health by observing actions households take to avoid exposure to arsenic in drinking water. Millions of Bangladeshis face multiple health hazards from high levels of arsenic in drinking water. Safe water sources are either expensive or difficult to access, affecting people’s individuals’ time available for work and ultimately affecting the health of household members. Since children are particularly susceptible and live with parents who are primary decision makers for sustenance, parental actions linking child health outcomes is used in the empirical model. Empirical results suggest that child health is significantly affected by the age and gender of the household water procurer. Adults with a high degree of concern for children’s health risk from arsenic contamination, and who actively mitigate their arsenic contaminated water have a positive effect on child health. PMID:24982854

  2. Factors affecting physical therapists’ job satisfaction: questionnaire survey targeting first-year physical therapists

    PubMed Central

    Kota, Munetsugu; Kudo, Hiroyuki; Okita, Kazuhiko

    2018-01-01

    [Purpose] The survey aimed to clarify the factors that affect physiotherapists’ job satisfaction. [Subjects and Methods] To examine factors affecting physical therapists’ job satisfaction using a cross-sectional study with a questionnaire survey. Subjects were 193 first-year physical therapists who participated in a newcomer orientation at Hiroshima Prefectural Physical Therapy Association. The questionnaire comprised items concerning physical therapists’ satisfaction with their work, motives for becoming physical therapists, education in school, internships, the workplace, and comfort in the workplace. [Results] Subjects were divided into two groups according to their satisfaction with their occupation. The “high satisfaction” group included 157 subjects, and the group “low satisfaction” group included 36 subjects. Using logistic regression analysis, items concerning comfort in the workplace, motives for becoming physical therapists, and learning in school were analysed. [Conclusion] Factors affecting physical therapists’ job satisfaction were primarily influenced by previous experience and working conditions. PMID:29706706

  3. Factors affecting physical therapists' job satisfaction: questionnaire survey targeting first-year physical therapists.

    PubMed

    Kota, Munetsugu; Kudo, Hiroyuki; Okita, Kazuhiko

    2018-04-01

    [Purpose] The survey aimed to clarify the factors that affect physiotherapists' job satisfaction. [Subjects and Methods] To examine factors affecting physical therapists' job satisfaction using a cross-sectional study with a questionnaire survey. Subjects were 193 first-year physical therapists who participated in a newcomer orientation at Hiroshima Prefectural Physical Therapy Association. The questionnaire comprised items concerning physical therapists' satisfaction with their work, motives for becoming physical therapists, education in school, internships, the workplace, and comfort in the workplace. [Results] Subjects were divided into two groups according to their satisfaction with their occupation. The "high satisfaction" group included 157 subjects, and the group "low satisfaction" group included 36 subjects. Using logistic regression analysis, items concerning comfort in the workplace, motives for becoming physical therapists, and learning in school were analysed. [Conclusion] Factors affecting physical therapists' job satisfaction were primarily influenced by previous experience and working conditions.

  4. Hydrogen bonding in a mixture of protic ionic liquids: a molecular dynamics simulation study.

    PubMed

    Paschek, Dietmar; Golub, Benjamin; Ludwig, Ralf

    2015-04-07

    We report results of molecular dynamics (MD) simulations characterising the hydrogen bonding in mixtures of two different protic ionic liquids sharing the same cation: triethylammonium-methylsulfonate (TEAMS) and triethylammonium-triflate (TEATF). The triethylammonium-cation acts as a hydrogen-bond donor, being able to donate a single hydrogen-bond. Both, the methylsulfonate- and the triflate-anions can act as hydrogen-bond acceptors, which can accept multiple hydrogen bonds via their respective SO3-groups. In addition, replacing a methyl-group in the methylsulfonate by a trifluoromethyl-group in the triflate significantly weakens the strength of a hydrogen bond from an adjacent triethylammonium cation to the oxygen-site in the SO3-group of the anion. Our MD simulations show that these subtle differences in hydrogen bond strength significantly affect the formation of differently-sized hydrogen-bonded aggregates in these mixtures as a function of the mixture-composition. Moreover, the reported hydrogen-bonded cluster sizes can be predicted and explained by a simple combinatorial lattice model, based on the approximate coordination number of the ions, and using statistical weights that mostly account for the fact that each anion can only accept three hydrogen bonds.

  5. Factors affecting wood energy consumption by U.S. households

    Treesearch

    Nianfu Song; Francisco X. Aguilar; Stephen R. Shifley; Michael E. Goerndt

    2012-01-01

    About 23% of energy derived from woody sources in the U.S. was consumed by households, of which 70% was used by households in rural areas in 2005. We investigated factors affecting household-level wood energy consumption in the four continental U.S. regions using data from the U.S. Residential Energy Consumption Survey. To account for a large number of zero...

  6. Disulfide Bond Formation and ToxR Activity in Vibrio cholerae

    PubMed Central

    Fengler, Vera H. I.; Boritsch, Eva C.; Tutz, Sarah; Seper, Andrea; Ebner, Hanna; Roier, Sandro; Schild, Stefan; Reidl, Joachim

    2012-01-01

    Virulence factor production in Vibrio cholerae is complex, with ToxRS being an important part of the regulatory cascade. Additionally, ToxR is the transcriptional regulator for the genes encoding the major outer membrane porins OmpU and OmpT. ToxR is a transmembrane protein and contains two cysteine residues in the periplasmic domain. This study addresses the influence of the thiol-disulfide oxidoreductase system DsbAB, ToxR cysteine residues and ToxR/ToxS interaction on ToxR activity. The results show that porin production correlates with ToxR intrachain disulfide bond formation, which depends on DsbAB. In contrast, formation of ToxR intrachain or interchain disulfide bonds is dispensable for virulence factor production and in vivo colonization. This study further reveals that in the absence of ToxS, ToxR interchain disulfide bond formation is facilitated, whereat cysteinyl dependent homo- and oligomerization of ToxR is suppressed if ToxS is coexpressed. In summary, new insights into gene regulation by ToxR are presented, demonstrating a mechanism by which ToxR activity is linked to a DsbAB dependent intrachain disulfide bond formation. PMID:23144706

  7. The main factor affecting the competitiveness of Contractor Company

    NASA Astrophysics Data System (ADS)

    Nurisra; Malahayati, Nurul; Mahmuddin

    2018-05-01

    Contractor companies must have the competitive advantage to compete in maintaining the survival of the company. Problems arise because quite a lot of advantages can be used and these advantages must be used appropriately to produce competitiveness for the company to continue to compete and to win the competition. This study aims to determine the main factors affecting the competitiveness of medium-class contractors in Banda Aceh. Data collection was obtained through questionnaires distributed to 31 middle-class contractors in Banda Aceh. Data processing and analysis is done by using descriptive analysis. Based on the result of descriptive analysis, it can be concluded that the most important competitiveness factor with a mean score value 4.52 is the relationship, and the factor that has the highest mean score value is the relationship with the government of 4.97, while the result of the ranking analysis is obtained 25 factor that is critical to the competitiveness of medium-class contractors in Banda Aceh.

  8. Molecularly Tuning the Radicaloid N-H···O═C Hydrogen Bond.

    PubMed

    Lu, Norman; Chung, Wei-Cheng; Ley, Rebecca M; Lin, Kwan-Yu; Francisco, Joseph S; Negishi, Ei-Ichi

    2016-03-03

    Substituent effects on the open shell N-H···O═C hydrogen-bond has never been reported. This study examines how 12 functional groups composed of electron donating groups (EDG), halogen atoms and electron withdrawing groups (EWG) affect the N-H···O═C hydrogen-bond properties in a six-membered cyclic model system of O═C(Y)-CH═C(X)N-H. It is found that group effects on this open shell H-bonding system are significant and have predictive trends when X = H and Y is varied. When Y is an EDG, the N-H···O═C hydrogen-bond is strengthened; and when Y is an EWG, the bond is weakened; whereas the variation in electronic properties of X group do not exhibit a significant impact upon the hydrogen bond strength. The structural impact of the stronger N-H···O═C hydrogen-bond are (1) shorter H and O distance, r(H···O) and (2) a longer N-H bond length, r(NH). The stronger N-H···O═C hydrogen-bond also acts to pull the H and O in toward one another which has an effect on the bond angles. Our findings show that there is a linear relationship between hydrogen-bond angle and N-H···O═C hydrogen-bond energy in this unusual H-bonding system. In addition, there is a linear correlation of the r(H···O) and the hydrogen bond energy. A short r(H···O) distance corresponds to a large hydrogen bond energy when Y is varied. The observed trends and findings have been validated using three different methods (UB3LYP, M06-2X, and UMP2) with two different basis sets.

  9. Thorium–phosphorus triamidoamine complexes containing Th–P single- and multiple-bond interactions

    PubMed Central

    Wildman, Elizabeth P.; Balázs, Gábor; Wooles, Ashley J.; Scheer, Manfred; Liddle, Stephen T.

    2016-01-01

    Despite the burgeoning field of uranium-ligand multiple bonds, analogous complexes involving other actinides remain scarce. For thorium, under ambient conditions only a few multiple bonds to carbon, nitrogen, oxygen, sulfur, selenium and tellurium are reported, and no multiple bonds to phosphorus are known, reflecting a general paucity of synthetic methodologies and also problems associated with stabilising these linkages at the large thorium ion. Here we report structurally authenticated examples of a parent thorium(IV)–phosphanide (Th–PH2), a terminal thorium(IV)–phosphinidene (Th=PH), a parent dithorium(IV)–phosphinidiide (Th–P(H)-Th) and a discrete actinide–phosphido complex under ambient conditions (Th=P=Th). Although thorium is traditionally considered to have dominant 6d-orbital contributions to its bonding, contrasting to majority 5f-orbital character for uranium, computational analyses suggests that the bonding of thorium can be more nuanced, in terms of 5f- versus 6d-orbital composition and also significant involvement of the 7s-orbital and how this affects the balance of 5f- versus 6d-orbital bonding character. PMID:27682617

  10. Thorium-phosphorus triamidoamine complexes containing Th-P single- and multiple-bond interactions.

    PubMed

    Wildman, Elizabeth P; Balázs, Gábor; Wooles, Ashley J; Scheer, Manfred; Liddle, Stephen T

    2016-09-29

    Despite the burgeoning field of uranium-ligand multiple bonds, analogous complexes involving other actinides remain scarce. For thorium, under ambient conditions only a few multiple bonds to carbon, nitrogen, oxygen, sulfur, selenium and tellurium are reported, and no multiple bonds to phosphorus are known, reflecting a general paucity of synthetic methodologies and also problems associated with stabilising these linkages at the large thorium ion. Here we report structurally authenticated examples of a parent thorium(IV)-phosphanide (Th-PH 2 ), a terminal thorium(IV)-phosphinidene (Th=PH), a parent dithorium(IV)-phosphinidiide (Th-P(H)-Th) and a discrete actinide-phosphido complex under ambient conditions (Th=P=Th). Although thorium is traditionally considered to have dominant 6d-orbital contributions to its bonding, contrasting to majority 5f-orbital character for uranium, computational analyses suggests that the bonding of thorium can be more nuanced, in terms of 5f- versus 6d-orbital composition and also significant involvement of the 7s-orbital and how this affects the balance of 5f- versus 6d-orbital bonding character.

  11. Closing in on chemical bonds by opening up relativity theory.

    PubMed

    Whitney, Cynthia K

    2008-03-01

    This paper develops a connection between the phenomenology of chemical bonding and the theory of relativity. Empirical correlations between electron numbers in atoms and chemical bond stabilities in molecules are first reviewed and extended. Quantitative chemical bond strengths are then related to ionization potentials in elements. Striking patterns in ionization potentials are revealed when the data are viewed in an element-independent way, where element-specific details are removed via an appropriate scaling law. The scale factor involved is not explained by quantum mechanics; it is revealed only when one goes back further, to the development of Einstein's special relativity theory.

  12. Ceramic susceptor for induction bonding of metals, ceramics, and plastics

    NASA Technical Reports Server (NTRS)

    Fox, Robert L.; Buckley, John D.

    1991-01-01

    A thin (.005) flexible ceramic susceptor (carbon) was discovered. It was developed to join ceramics, plastics, metals, and combinations of these materials using a unique induction heating process. Bonding times for laboratory specimens comparing state of the art technology to induction bonding were cut by a factor of 10 to 100 times. This novel type of carbon susceptor allows for applying heat directly and only to the bondline without heating the entire structure, supports, and fixtures of a bonding assembly. The ceramic (carbon film) susceptor produces molten adhesive or matrix material at the bond interface. This molten material flows through the perforated susceptor producing a fusion between the two parts to be joined, which in many instances has proven to be stronger than the parent material. Bonding can be accomplished in 2 minutes on areas submitted to the inductive heating. Because a carbon susceptor is used in bonding carbon fiber reinforced plastics and ceramics, there is no radar signature or return making it an ideal process for joining advanced aerospace composite structures.

  13. Bidentate, monoanionic auxiliary-directed functionalization of carbon-hydrogen bonds.

    PubMed

    Daugulis, Olafs; Roane, James; Tran, Ly Dieu

    2015-04-21

    In recent years, carbon-hydrogen bond functionalization has evolved from an organometallic curiosity to a tool used in mainstream applications in the synthesis of complex natural products and drugs. The use of C-H bonds as a transformable functional group is advantageous because these bonds are the most abundant functionality in organic molecules. One-step conversion of these bonds to the desired functionality shortens synthetic pathways, saving reagents, solvents, and labor. Less chemical waste is generated as well, showing that this chemistry is environmentally beneficial. This Account describes the development and use of bidentate, monoanionic auxiliaries for transition-metal-catalyzed C-H bond functionalization reactions. The chemistry was initially developed to overcome the limitations with palladium-catalyzed C-H bond functionalization assisted by monodentate directing groups. By the use of electron-rich bidentate directing groups, functionalization of unactivated sp(3) C-H bonds under palladium catalysis has been developed. Furthermore, a number of abundant base-metal complexes catalyze functionalization of sp(2) C-H bonds. At this point, aminoquinoline, picolinic acid, and related compounds are among the most used and versatile directing moieties in C-H bond functionalization chemistry. These groups facilitate catalytic functionalization of sp(2) and sp(3) C-H bonds by iron, cobalt, nickel, copper, ruthenium, rhodium, and palladium complexes. Exceptionally general reactivity is observed, enabling, among other transformations, direct arylation, alkylation, fluorination, sulfenylation, amination, etherification, carbonylation, and alkenylation of carbon-hydrogen bonds. The versatility of these auxilaries can be attributed to the following factors. First, they are capable of stabilizing high oxidation states of transition metals, thereby facilitating the C-H bond functionalization step. Second, the directing groups can be removed, enabling their use in

  14. Bidentate, Monoanionic Auxiliary-Directed Functionalization of Carbon–Hydrogen Bonds

    PubMed Central

    Daugulis, Olafs; Roane, James; Tran, Ly Dieu

    2015-01-01

    CONSPECTUS In recent years, carbon–hydrogen bond functionalization has evolved from an organometallic curiosity to mainstream applications in the synthesis of complex natural products and drugs. The use of C–H bonds as a transformable functional group is advantageous because these bonds are the most abundant functionality in organic molecules. One-step conversion of these bonds to the desired functionality shortens synthetic pathways, saving reagents, solvents, and labor. Less chemical waste is generated as well, showing that this chemistry is environmentally beneficial. This Account describes the development and use of bidentate, monoanionic auxiliaries for transition-metal-catalyzed C–H bond functionalization reactions. The chemistry was initially developed to overcome the limitations with palladium-catalyzed C–H bond functionalization assisted by monodentate directing groups. By the use of electron-rich bidentate directing groups, functionalization of unactivated sp3 C–H bonds under palladium catalysis has been developed. Furthermore, a number of abundant base-metal complexes catalyze functionalization of sp2 C–H bonds. At this point, aminoquinoline, picolinic acid, and related compounds are among the most used and versatile directing moieties in C–H bond functionalization chemistry. These groups facilitate catalytic functionalization of sp2 and sp3 C–H bonds by iron, cobalt, nickel, copper, ruthenium, rhodium, and palladium complexes. Exceptionally general reactivity is observed, enabling, among other transformations, direct arylation, alkylation, fluorination, sulfenylation, amination, etherification, carbonylation, and alkenylation of carbon–hydrogen bonds. The versatility of these auxilaries can be attributed to the following factors. First, they are capable of stabilizing high oxidation states of transition metals, thereby facilitating the C–H bond functionalization step. Second, the directing groups can be removed, enabling their use in

  15. Effects of bonding with parents and home culture on intercultural adaptations and the moderating role of genes.

    PubMed

    Phua, Desiree Y; Meaney, Michael J; Khor, Chiea Chuen; Lau, Ivy Y M; Hong, Ying-Yi

    2017-05-15

    In the current age of globalization, living abroad is becoming an increasingly common and highly sought after experience. Sojourners' ability to adjust to a new culture can be affected by their existing attachments, internalized as intrapsychic environment, as well as their biological sensitivity to environment. This sensitivity can be partly attributed to one's genomic endowments. As such, this prospective study sought to examine the differential effects of early experiences with parents and affection for home culture on young adults' ability to adapt to a foreign culture (n=305, students who studied overseas for a semester) - specifically, the difficulties they experience - moderated by genetic susceptibility. An additional 258 students who did not travel overseas were included as a comparison group to demonstrate the uniqueness of intercultural adaptation. Current findings suggest that the maternal, paternal and cultural bondings or affections affect different aspects of intercultural adjustment. Maternal bonding affected sojourners' relationships with host nationals, while paternal bonding affected sojourners' adjustment to a new physical environment. Moreover, individuals' genetic predispositions significantly moderate these main effects regarding how much difficulty the sojourners experienced overseas. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Effect of saliva contamination and artificial aging on different primer/cement systems bonded to zirconia.

    PubMed

    Pitta, João; Branco, Teresa C; Portugal, Jaime

    2018-05-01

    Saliva contamination has been shown to decrease bonding to zirconia. Adopting a less contamination-sensitive cement system may be an alternative to decontamination. The purpose of this in vitro study was to assess the ability of different primer/cement systems to promote a durable bond to zirconia after saliva contamination. Zirconia blocks (Lava Plus) (N=320) were airborne-particle abraded (50 μm Al 2 O 3 ) and divided into 32 experimental groups (n=10) according to the variables in the study: saliva contamination; primer/cement system (Panavia SA [PSA]; RelyX Unicem 2 [RU2]; Bifix SE [BSE]; Panavia F2.0 [PF2]; Scotchbond Universal + RelyX Ultimate [SBU+RXU]; Futurabond M+ + Bifix QM [FBM+BQM]; All-Bond Universal + Duo-link [ABU+DL]; Z-Prime Plus + Duo-link [ZPP+DL]; and aging period (72 hours; 30 days with 10 000 thermocycles at 5°C to 55°C). After half of the blocks had been contaminated with fresh human saliva for 10 minutes, rinsed with water, and air-dried, each primer/cement was applied. Polymerized composite resin disks were then placed over the cement, and the resin cement was light-polymerized for 20 seconds each at 2 opposite margins. After the aging time, the specimens were tested in shear (1 mm/min). The failure mode was classified as adhesive, cohesive, or mixed. Statistical analysis of the shear bond strength (SBS) data was performed with ANOVA followed by Tukey honest significant difference post hoc tests. Chi-square tests were used to analyze the failure mode data (α=.05). The mean SBS ranged between 4.2 and 34.5 MPa. Shear bond strength was influenced (P<.001) by all the factors studied (cement system, saliva contamination, aging time). SBU+RXU and FBM+BQM showed a higher mean SBS than those of the other experimental groups (P<.05) and were the only groups not affected by saliva contamination (P>.05). Failure was predominantly classified as adhesive. In general, saliva contamination and aging decreased bonding efficacy. Two systems

  17. Factors Affecting the Formation of Food Preferences in Preschool Children.

    ERIC Educational Resources Information Center

    Alles-White, Monica L.; Welch, Patricia

    1985-01-01

    Identifies and discusses factors that affect the development of food preferences in preschool children, including familiarity, age, parents, peers, teachers, and programs designed to influence food habits. Makes recommendations to preschool and day care programs for creating an atmosphere conducive to trying new foods. (Author/DST)

  18. Risk factors for injuries in landslide- and flood-affected populations in Uganda.

    PubMed

    Agrawal, Shreya; Gopalakrishnan, Tisha; Gorokhovich, Yuri; Doocy, Shannon

    2013-08-01

    The frequency of occurrence of natural disasters has increased over the past several decades, which necessitates a better understanding of human vulnerability, particularly in low-resource settings. This paper assesses risk factors for injury in the March 2010 floods and landslides in Eastern Uganda, and compares the effects of location, injury type, and severity. A stratified cluster survey of the disaster-affected populations was conducted five months after onset of the disasters. Probability proportional to size sampling was used to sample 800 households, including 400 affected by floods in Butaleja District and 400 affected by landslides in Bududa District. Flood- and landslide-affected populations were surveyed in July 2010 using a stratified cluster design. The odds of injury were 65% higher in the flood-affected groups than the landslide-affected groups in a logistic regression (OR = 0.35; 95% CI, 0.24-0.52; P < .001). The injury rate was greater in individuals under 42 years of age, and location of injury was a contributing factor. More people were injured in the flood-affected population as compared with the landslide-affected population, and injuries were more severe. This study illustrates differences between populations injured by flood and landslide disasters that occurred simultaneously in Eastern Uganda in 2010. In areas where landslides are prone to occur due to massive rainfalls or floods, preventative measures, such as early warning systems and evacuation, are more likely to increase the likelihood of people surviving, while for areas with massive floods, immediate and effective medical attention can save lives and improve injury outcomes.

  19. Chemical activation of molecules by metals: Experimental studies of electron distributions and bonding

    NASA Astrophysics Data System (ADS)

    Lichtenberg, Dennis L.

    During this period some important breakthroughs were accomplished in understanding the relationships between molecular ionization energies and bond energies in transition metal complexes, in understanding the electronic factors of carbon-hydrogen bond activation by transition metals, in characterizing small molecule bonding interactions with transition metals, and in investigating intermolecular interactions in thin films of transition metal complexes. The formal relationship between measured molecular ionization energies and thermodynamic bond dissociation energies was developed into a single equation which unifies the treatment of covalent bonds, ionic bonds, and partially ionic bonds. The relationship was used to clarify the fundamental thermodynamic information relating to metal-hydrogen, metal-alkyl, and metal-metal bond energies. The ionization energies were also used to correlate the rates of carbonyl substitution reactions of (eta(sup 5)-C5H4X)Rh(CO)2 complexes, and to reveal the factors that control the stability of the transition state. The investigations of the fundamental interactions of C-H sigma and sigma* orbitals metals were continued with study of eta(sup 3)-1-methylallyl metal complexes. Direct observation and measurement of the stabilization energy provided by the agostic interaction of the C-H bond with the metal was obtained. The ability to observe the electronic effects of intermolecular interactions by comparing the ionizations of metal complexes in the gas phase with the ionizations of thin solid organometallic films prepared in ultra-high vacuum was established. Most significantly, the scanning tunneling microscope imaging of these thin films was accomplished.

  20. Factors affecting smoking in schizophrenia.

    PubMed

    Beratis, S; Katrivanou, A; Gourzis, P

    2001-01-01

    There is an increased frequency of smoking among patients with schizophrenia. However, it is unknown whether the smoking behavior of the patients is similar in all schizophrenia subtypes, as well as which is the relationship between smoking initiation and disease onset. Four hundred six patients with DSM-IV schizophrenia were interviewed to determine the smoking status in relationship to gender and schizophrenic subtype, and to other factors that could affect or be affected by smoking. The frequency of smoking among patients (58%) was significantly greater than in subjects from the general population (42%) (P =.000005). Male patients smoked significantly more frequently (70%) than the corresponding control subjects (50%) (P =.000006), whereas the difference failed to reach significance between female patients (41%) and control subjects (32%). Among male patients, the number of smokers was significantly greater than in the controls in the paranoid (77%), undifferentiated (72%), and residual (78%) subtypes, whereas there was no significant difference in the disorganized (44%) and catatonic (22%) subtypes. The findings show that the frequency of smoking in schizophrenia patients increases with increasing positive symptoms and decreases with increasing negative symptoms. Male and female smoking patients consumed approximately 10 cigarettes per day more than the corresponding control subjects (P <.000001). In 86% of the patients, smoking initiation occurred before the disease onset. Among patients who smoked, smoking initiation and disease onset occurred at age 18.7 +/- 4.4 and 24.1 +/- 6.1 years, respectively (P <.000001). It appears that smoking in schizophrenia is influenced by gender and subtype. However, the nature of this association remains uncertain because in the vast majority of the patients smoking initiation occurs earlier than the disease onset. Copyright 2001 by W.B. Saunders Company

  1. Companion of choice at birth: factors affecting implementation.

    PubMed

    Kabakian-Khasholian, Tamar; Portela, Anayda

    2017-08-31

    Two recent recommendations made by the World Health Organization confirm the benefits of companion of choice at birth on labour outcomes; however institutional practices and policies do not always support its implementation in different settings around the world. We conducted a review to determine factors that affect implementation of this intervention considering the perspectives and experiences of different stakeholders and other institutional, systemic barriers and facilitators. Forty one published studies were included in this review. Thirty one publications were identified from a 2013 Cochrane review on the effectiveness of companion of choice at birth. We also reviewed 10 qualitative studies conducted alongside the trials or other interventions on labour and birth companionship identified through electronic searches. The SURE (Supporting the Use of Research Evidence) framework was used to guide the thematic analysis of implementation factors. Women and their families expressed appreciation for the continuous presence of a person to provide support during childbirth. Health care providers were concerned about the role of the companion and possible interference with activities in the labour ward. Allocation of resources, organization of care, facility-related constraints and cultural inclinations were identified as implementation barriers. Prior to introducing companion of choice at birth, understanding providers' attitudes and sensitizing them to the evidence is necessary. The commitment of the management of health care facilities is also required to change policies, including allocation of appropriate physical space that respects women's privacy. Implementation research to develop models for different contexts which could be scaled up would be useful, including documentation of factors that affected implementation and how they were addressed. Future research should also focus on documenting the costs related to implementation, and on measuring the impact of

  2. The influence of plain bar on bond strength of geopolymer concrete

    NASA Astrophysics Data System (ADS)

    Dewi, Evrianti Syntia; Ekaputri, Januarti Jaya

    2017-06-01

    This paper presents some results of experimental study of bond strength of plain bar embedded in geopolymer concrete. Fly ash class F was used as a raw material activated with alkali solutions. The combination of 8 Molar of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) as alkali activators was examined in the mixture with ratio of 2.5 by weight. Nine cubical specimens with a size of 150 × 150 × 150 mm were prepared to measure bond strength and slip between reinforcement and concrete. The influential factors studied for the experimental investigation were the diameter of reinforcement bar, bond area, and concrete cover to diameter (c/d) of reinforcement. The result showed that the average bond strength decreased as the diameter of plain bar and bonded length were increased from 16 mm to 19 mm. However, the 12 mm showed the different result allegedly caused by the effect of bond area and the passive confined provided by the concrete. Based on several equations used to compare the bond strength, it is clear that deformed bar of 12 mm in diameter is potential to increase the bond strength.

  3. Association between parental depressive symptoms and impaired bonding with the infant.

    PubMed

    Kerstis, Birgitta; Aarts, Clara; Tillman, Carin; Persson, Hanna; Engström, Gabriella; Edlund, Birgitta; Öhrvik, John; Sylvén, Sara; Skalkidou, Alkistis

    2016-02-01

    Impaired bonding with the infant is associated with maternal postpartum depression but has not been investigated extensively in fathers. The primary study aim was to evaluate associations between maternal and paternal depressive symptoms and impaired bonding with their infant. A secondary aim was to determine the associations between parents' marital problems and impaired bonding with the infant. The study is part of a population-based cohort project (UPPSAT) in Uppsala, Sweden. The Edinburgh Postnatal Depression Scale (EPDS) at 6 weeks and 6 months postpartum and the Postpartum Bonding Questionnaire at 6 months postpartum were completed by 727 couples. The prevalence of impaired bonding was highest among couples in which both spouses had depressive symptoms. Impaired bonding was associated with higher EPDS scores in both mothers and fathers, as well as with experiencing a deteriorated marital relationship. The association between maternal and paternal impaired bonding and the mothers' and fathers' EPDS scores remained significant even after adjustment for relevant confounding factors. Depressive symptoms at 6 weeks postpartum are associated with impaired bonding with the infant at 6 months postpartum for both mothers and fathers. It is critical to screen for and prevent depressive symptoms in both parents during early parenthood.

  4. The Rhetoric of Bonds, Alliances, and Identities: Interrogating Social Networks in Early Modern English Drama

    ERIC Educational Resources Information Center

    Cady, Christina J.

    2010-01-01

    The household and family have received considerable interest in studies of early modern English drama, but less attention has been paid to how writers represent intimate affective bonds on the stage. Emotion is intangible; yet many writers convincingly convey the intensity of emotional bonds through rhetoric. Rhetoric is a mainstay in…

  5. Influence of Hemostatic Solution on Bond Strength and Physicochemical Properties of Resin Cement.

    PubMed

    Araújo, Isabela Sousa de; Prado, Célio Jesus do; Raposo, Luís Henrique Araújo; Soares, Carlos José; Zanatta, Rayssa Ferreira; Torres, Carlos Rocha Gomes; Ruggiero, Reinaldo; Silva, Gisele Rodrigues da

    2017-01-01

    The aim of this study was to evaluate the degree of conversion, color stability, chemical composition, and bond strength of a light-cured resin cement contaminated with three different hemostatic solutions. Specimens were prepared for the control (uncontaminated resin cement) and experimental groups (resin cement contaminated with one of the hemostatic solutions) according to the tests. For degree of conversion, DC (n = 5) and color analyses (n = 10), specimens (3 mm in diameter and 2 mm thick) were evaluated by Fourier transform infrared spectroscopy (FTIR) and CIELAB spectrophotometry (L*, a*, b*), respectively. For elemental chemical analysis (n = 1), specimens (2 mm thick and 6 mm in diameter) were evaluated by x-ray energy-dispersive spectroscopy (EDS). The bond strengths of the groups were assessed by the microshear test (n = 20) in a leucite-reinforced glass ceramic substrate, followed by failure mode analysis by scanning electron microscopy (SEM). The mean values, except for the elemental chemical evaluation and failure mode, were evaluated by ANOVA and Tukey's HSD test. The color stability was influenced by storage time (p<0.001) and interaction between contamination and storage time (p<0.001). Hemostop and Viscostat Clear contamination did not affect the DC, however Viscostat increased the DC. Bond strength of the resin cement to ceramic was negatively affected by the contaminants (p<0.001). Contamination by hemostatic agents affected the bond strength, degree of conversion, and color stability of the light-cured resin cement tested.

  6. Parental bonding and suicidality in adulthood.

    PubMed

    Heider, Dirk; Bernert, Sebastian; Matschinger, Herbert; Haro, Josep M; Alonso, Jordi; Angermeyer, Matthias C

    2007-01-01

    The short-term effect of an adverse parental child rearing style on suicidality in adolescence has been extensively discussed. Nevertheless, little is known about the long-term effect of adverse parental child rearing on lifetime suicidality in adulthood. So the present study aims to examine the relation between parental bonding on the one hand and suicidality in adulthood on the other. We used data from 7740 respondents of the European Study of Epidemiology of Mental Disorders project, a cross-sectional household survey carried out in six European countries. The data were assessed with the World Mental Health Composite International Diagnostic Interview, a comprehensive, fully structured psychiatric diagnostic interview. Suicidality was categorized as follows: 'no ideation', 'ideation', 'attempt'. Parental bonding was assessed by means of a three-factor ('care', 'overprotection', 'authoritarianism') short form of the Parental Bonding Instrument. Using a multinomial-logistic regression model to investigate the association between these two constructs, we also adjusted for mood disorders, anxiety disorders, alcohol abuse/dependence and possible country effects. We found associations between low maternal and paternal care on the one hand and suicidality on the other. Country-specific differences proved negligible. Prevention programs can help better equip parents in their child-rearing role to create a more caring parenting environment. This can be a protective factor for suicidality in adulthood. Nevertheless, more efforts are necessary to better describe the paths that lead from child-rearing behaviour to suicidality in adulthood.

  7. Pauling's electronegativity equation and a new corollary accurately predict bond dissociation enthalpies and enhance current understanding of the nature of the chemical bond.

    PubMed

    Matsunaga, Nikita; Rogers, Donald W; Zavitsas, Andreas A

    2003-04-18

    Contrary to other recent reports, Pauling's original electronegativity equation, applied as Pauling specified, describes quite accurately homolytic bond dissociation enthalpies of common covalent bonds, including highly polar ones, with an average deviation of +/-1.5 kcal mol(-1) from literature values for 117 such bonds. Dissociation enthalpies are presented for more than 250 bonds, including 79 for which experimental values are not available. Some previous evaluations of accuracy gave misleadingly poor results by applying the equation to cases for which it was not derived and for which it should not reproduce experimental values. Properly interpreted, the results of the equation provide new and quantitative insights into many facets of chemistry such as radical stabilities, factors influencing reactivity in electrophilic aromatic substitutions, the magnitude of steric effects, conjugative stabilization in unsaturated systems, rotational barriers, molecular and electronic structure, and aspects of autoxidation. A new corollary of the original equation expands its applicability and provides a rationale for previously observed empirical correlations. The equation raises doubts about a new bonding theory. Hydrogen is unique in that its electronegativity is not constant.

  8. Effects of bond primers on bending strength and bonding of glass fibers in fiber-embedded maxillofacial silicone prostheses.

    PubMed

    Hatamleh, Muhanad M; Watts, David C

    2011-02-01

    To evaluate the effect of three commonly used bond primers on the bending strength of glass fibers and their bond strength to maxillofacial silicone elastomer after 360 hours of accelerated daylight aging. Eighty specimens were fabricated by embedding resin-impregnated fiber bundles (1.5-mm diameter, 20-mm long) into maxillofacial silicone elastomer M511 (Cosmesil). Twenty fiber bundles served as control and did not receive surface treatment with primers, whereas the remaining 60 fibers were treated with three primers (n = 20): G611 (Principality Medical), A-304 (Factor II), and A-330-Gold (Factor II). Forty specimens were dry stored at room temperature (23 ± 1°C) for 24 hours, and the remaining specimens were aged using an environmental chamber under accelerated exposure to artificial daylight for 360 hours. The aging cycle included continuous exposure to quartz-filtered visible daylight (irradiance 760 W/m(2) ) under an alternating weathering cycle (wet for 18 minutes, dry for 102 minutes). Pull-out tests were performed to evaluate bond strength between fiber bundles and silicone using a universal testing machine at 1 mm/min crosshead speed. A 3-point bending test was performed to evaluate the bending strength of the fiber bundles. One-way Analysis of Variance (ANOVA), Bonferroni post hoc test, and an independent t-test were carried out to detect statistical significances (p < 0.05). Mean (SD) values of maximum pull-out forces (N) before aging for groups: no primer, G611, A-304, A-330-G were: 13.63 (7.45), 20.44 (2.99), 22.06 (6.69), and 57.91 (10.15), respectively. All primers increased bond strength in comparison to control specimens (p < 0.05). Primer A-330-G showed the greatest increase among all primers (p < 0.05); however, bonding degraded after aging (p < 0.05), and pull-out forces were 13.58 (2.61), 6.17 (2.89), 6.95 (2.61), and 11.72 (3.03). Maximum bending strengths of fiber bundles at baseline increased after treatment with primers and light aging in

  9. The Synergistic Effect of Affective Factors on Student Learning Outcomes

    ERIC Educational Resources Information Center

    Jack, Brady Michael; Lin, Huann-shyang; Yore, Larry D.

    2014-01-01

    This study investigates how affective and self-related factors impact participation in science learning and environmental awareness and responsibility. Using PISA 2006 datasets from Taiwan and Canada having similar level of science competency, the model for this study verifies and expands an earlier model by examining the relationships among…

  10. Factors Affecting Educational Innovation with in Class Electronic Response Systems

    ERIC Educational Resources Information Center

    Freeman, Mark; Bell, Amani; Comerton-Forde, Carole; Pickering, Joanne; Blayney, Paul

    2007-01-01

    This paper reports the use of Rogers' diffusion of innovation perspective to understand the factors affecting educational innovation decisions, specifically in regard to in class electronic response systems. Despite decreasing costs and four decades of research showing strong student support, academic adoption is limited. Using data collected from…

  11. Scrutinizing the Factors Affecting Fluency of English among Arab Learners

    ERIC Educational Resources Information Center

    Al Ghazali, Fawzi

    2017-01-01

    This research study investigates the cognitive, psychological and personal factors affecting the accuracy and fluency of English language usage among Arab learners. Early research led by Chomsky (1965) and Krashen (1981) suggested that an individual's Language Acquisition Device once triggered at the appropriate time and supported with adequate…

  12. Factors Affecting the Acceptability of Microforms as a Reading Medium.

    ERIC Educational Resources Information Center

    Spencer, Herbert; Reynolds, Linda

    Based on visits to representative microform users and an extensive survey of relevant literature, a study was undertaken to assess the relative importance of factors affecting the acceptability of microforms as reading mediums. The following variables were considered: (1) microform characteristics; (2) equipment design; (3) work station design;…

  13. Environmental factors affecting understory diversity in second-growth deciduous forests

    Treesearch

    Cynthia D. Huebner; J.C. Randolph; G.R. Parker

    1995-01-01

    The purpose of this study was to determine the most important nonanthropogenic factors affecting understory (herbs, shrubs and low-growing vines) diversity in forested landscapes of southern Indiana. Fourteen environmental variables were measured for 46 sites. Multiple regression analysis showed significant positive correlation between understory diversity and tree...

  14. Factors Affecting School Choice: What Do Malaysian Chinese Parents Want?

    ERIC Educational Resources Information Center

    Siah, Poh Chua; Christina Ong, Sook Beng; Tan, Swee Mee; Sim, Chzia Poaw; Xian Thoo, Raphael Yi

    2018-01-01

    Aiming to explore factors affecting Malaysian Chinese parents in sending their children to either national secondary schools or Chinese independent schools, 494 parents were surveyed using a questionnaire. Results showed that parents who sent their children to Chinese independent schools have different priorities compared to those who sent theirs…

  15. Risk factors affecting human traumatic tympanic membrane perforation regeneration therapy using fibroblast growth factor-2.

    PubMed

    Lou, Zhengcai; Yang, Jian; Tang, Yongmei; Xiao, Jian

    2015-01-01

    The use of growth factors to achieve closure of human traumatic tympanic membrane perforations (TMPs) has recently been demonstrated. However, pretreatment factors affecting healing outcomes have seldom been discussed. The objective of this study was to evaluate pretreatment factors contributing to the success or failure of healing of TMPs using fibroblast growth factor-2 (FGF-2). A retrospective cohort study of 99 patients (43 males, 56 females) with traumatic TMPs who were observed for at least 6 months after FGF-2 treatment between March 2011 and December 2012. Eleven factors considered likely to affect the outcome of perforation closure were evaluated statistically using univariate and multivariate logistic regression analysis. Each traumatic TMP was treated by direct application of FGF-2. Complete closure versus failure to close. In total, 99 patients were analyzed. The total closure rate was 92/99 (92.9%) at 6 months; the mean closure time was 10.59 ±  6.81 days. The closure rate did not significantly differ between perforations with or without inverted edges (100.0% vs. 91.4%, p = 0.087), among different size groups (p = 0.768), or among different periods of exposure to injury (p = 0.051). However, the closure rate was significantly different between the high- and low-dose FGF-2 groups (85.0% vs. 98.3%, p = 0.010) and between perforations where the umbo or malleus was or was not involved in perforation (85.4% vs. 98.3%, p = 0.012). Additionally, univariate logistic regression analysis tests showed that it was difficult to achieve healing of these perforations with a history of chronic otitis media or residual TM calcification (p = 0.006), the umbo or malleus was involved in perforation (p = 0.038), and with a high dose of FGF-2 (p = 0.035) compared with control groups. Multivariate logistic regression analysis showed that only a history of chronic otitis media and residual TM calcification and perforation close to the

  16. Factors affecting alkali jarosite precipitation

    NASA Astrophysics Data System (ADS)

    Dutrizac, J. E.

    1983-12-01

    Several factors affecting the precipitation of the alkali jarosites (sodium jarosite, potassium jarosite, rubidium jarosite, and ammonium jarosite) have been studied systematically using sodium jarosite as the model. The pH of the reacting solution exercises a major influence on the amount of jarosite formed, but has little effect on the composition of the washed product. Higher temperatures significantly increase the yield and slightly raise the alkali content of the jarosites. The yield and alkali content both increase greatly with the alkali concentration to about twice the stoichiometric requirement but, thereafter, remain nearly constant. At 97 °C, the amount of product increases with longer retention times to about 15 hours, but more prolonged reaction times are without significant effect on the amount or composition of the jarosite. Factors such as the presence of seed or ionic strength have little effect on the yield or jarosite composition. The amount of precipitate augments directly as the iron concentration of the solution increases, but the product composition is nearly independent of this variable. A significant degree of agitation is necessary to suspend the product and to prevent the jarosite from coating the apparatus with correspondingly small yields. Once the product is adequately suspended, however, further agitation is without significant effect. The partitioning of alkali ions during jarosite precipitation was ascertained for K:Na, Na:NH4, K:NH4, and K:Rb. Potassium jarosite is the most stable of the alkali jarosites and the stability falls systematically for lighter or heavier congeners; ammonium jarosite is slightly more stable than the sodium analogue. Complete solid solubility among the various alkali jarosite-type compounds was established.

  17. [Phosphorus availability in cropland soils of China and related affecting factors].

    PubMed

    Wang, Yong-Zhuang; Chen, Xin; Shi, Yi

    2013-01-01

    Soil phosphorus (P) availability directly determines cropland productivity. Based on the long-term fertilization experiments in different climatic zones of China, this paper summarized the P content, its availability, and the factors affecting the P transformation in China cropland soils. The total and available P contents in different types of China cropland soils were 0.31-1.72 g x kg(-1) and 0.1-228.8 mg x kg(-1), respectively. Soil parent material, soil physical and chemical prosperities, and fertilization practices were the main factors affecting the soil P availability. It was suggested that more attentions should be paid on the mixed application of organic manure and chemical fertilizers to improve the P availability of cropland soils and on the potential environmental impacts of this fertilization.

  18. Factors affecting workplace bullying and lateral violence among clinical nurses in Korea: descriptive study.

    PubMed

    Oh, Hyunjin; Uhm, Dong Choon; Yoon, Young Joo

    2016-04-01

    Workplace bullying and lateral violence are serious issues affecting the work life of hospital nurses. The purpose of this study was to identify the selected individual and institutional characteristics for workplace bullying and lateral violence using a conceptual framework. A descriptive survey design was used. A convenience sample of 255 nurses in tertiary hospitals, who had a minimum of 6 months clinical experience, completed the survey. Regression analysis was used to determine factors significantly associated with workplace bullying and lateral violence. The Negative Acts Questionnaire-Revised and the Lateral Violence scale were used to measure workplace bullying and lateral violence. A negative affect, individualism and working in hospital specialty units predicted workplace bullying. Individualism, a negative affect, affiliated hospital and working hours predicted verbal abuse whereas the place of employment was significantly associated with lateral violence. The results of this study identified factors that are associated with bullying and violence but did not fully support the conceptual framework. The individual characteristic negative affect was significantly associated with most types of workplace bullying and lateral violence bully whereas the place of employment was an important factor in lateral violence. Nurse managers need to be aware that both individual and institutional factors may impact levels of workplace bullying and lateral violence in their hospitals and need to prepare specific strategies to address these multiple factors. © 2015 John Wiley & Sons Ltd.

  19. Factors affecting length of stay in teaching hospitals of a middle-income country

    PubMed Central

    Khosravizadeh, Omid; Vatankhah, Soudabeh; Bastani, Peivand; Kalhor, Rohollah; Alirezaei, Samira; Doosty, Farzane

    2016-01-01

    Introduction The length of stay (LOS) in hospitals is a widely used and important criteria for evaluating hospital performance. The aim of this study was to determine factors affecting LOS in teaching hospitals of Qazvin Providence. Methods In this cross-sectional study, patients’ health records were randomly selected from archives in teaching hospitals of Qazvin in 2013. Data were collected through a data entry form and were analyzed using Kolmogorov–Smirnov, Kruskal–Wallis, and Mann–Whitney U tests at the significant level of 0.05. Results The mean of hospital LOS was 5.45 ± 6.14 days. Age, employment, marital status, history of previous admission, patient condition at discharge, method of payment, and type of treatment had an impact on LOS (p<0.05). Other factors, including gender, place of residence, and type of admission, did not affect LOS. Conclusion Because hospitals consume a perceptible part of resources in a health system, controlled and optimized use of its resources help to save a lot. Therefore, this study showed many clinical and nonclinical factors affect LOS in evaluating these factors, which may reduce inappropriate hospital stays and decrease costs. PMID:27957301

  20. Analysis of usability factors affecting purchase intention in online e-commerce sites

    NASA Astrophysics Data System (ADS)

    Perdana, R. A.; Suzianti, A.

    2017-03-01

    The growing number of internet users plays a significant role in the emergence of a variety of online e-commerce sites to meet the needs of Indonesians. However, there are still some problems faced by the users in using e-commerce sites. Therefore, a research related to user experience on their purchase intention to foster e-commerce sites is required. This study is conducted to find out the relationship between usability factors on e-commerce users’ purchase intention using a case study by using SEM to analyse the usability of the website. The result of this study shows that credibility, readability and telepresence are usability factors that directly affect purchase intention, while simplicity, consistency and interactivity are usability factors that indirectly affect purchase intention. Therefore, we can conclude that Indonesian consumers are on the Early Majority phase in adopting Company A.

  1. The Internal Structure of Positive and Negative Affect: A Confirmatory Factor Analysis of the PANAS

    ERIC Educational Resources Information Center

    Tuccitto, Daniel E.; Giacobbi, Peter R., Jr.; Leite, Walter L.

    2010-01-01

    This study tested five confirmatory factor analytic (CFA) models of the Positive Affect Negative Affect Schedule (PANAS) to provide validity evidence based on its internal structure. A sample of 223 club sport athletes indicated their emotions during the past week. Results revealed that an orthogonal two-factor CFA model, specifying error…

  2. Factors affecting midwives' confidence in intrapartum care: a phenomenological study.

    PubMed

    Bedwell, Carol; McGowan, Linda; Lavender, Tina

    2015-01-01

    midwives are frequently the lead providers of care for women throughout labour and birth. In order to perform their role effectively and provide women with the choices they require midwives need to be confident in their practice. This study explores factors which may affect midwives' confidence in their practice. hermeneutic phenomenology formed the theoretical basis for the study. Prospective longitudinal data collection was completed using diaries and semi-structured interviews. Twelve midwives providing intrapartum care in a variety of settings were recruited to ensure a variety of experiences in different contexts were captured. the principal factor affecting workplace confidence, both positively and negatively, was the influence of colleagues. Perceived autonomy and a sense of familiarity could also enhance confidence. However, conflict in the workplace was a critical factor in reducing midwives' confidence. Confidence was an important, but fragile, phenomenon to midwives and they used a variety of coping strategies, emotional intelligence and presentation management to maintain it. this is the first study to highlight both the factors influencing midwives' workplace confidence and the strategies midwives employed to maintain their confidence. Confidence is important in maintaining well-being and workplace culture may play a role in explaining the current low morale within the midwifery workforce. This may have implications for women's choices and care. Support, effective leadership and education may help midwives develop and sustain a positive sense of confidence. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Specifying the non-specific factors underlying opioid analgesia: Expectancy, attention, and affect

    PubMed Central

    Atlas, Lauren Y.; Wielgosz, Joseph; Whittington, Robert A.; Wager, Tor D.

    2013-01-01

    Rationale Psychological processes such as expectancy, attention, and affect directly influence clinical outcomes. These factors are grouped together as “nonspecific” factors, or placebo effects, in the medical literature, and their individual contributions are rarely considered. The pain-reducing effects of analgesic treatments may reflect changes in these psychological factors, rather than pure drug effects on pain. Furthermore, drug effects may not be isolated by drug vs. placebo comparisons if drugs interact with relevant psychological processes. Objectives To determine whether the analgesic effects of opioid and placebo treatment are mediated by changes in attention, expectancy, or affect. Methods We crossed intravenous administration of a potent opioid analgesic, remifentanil, with information about drug delivery (treatment expectancy, or placebo) using a balanced placebo design. We measured drug and treatment expectancy effects on pain, attention, and responses to emotional images. We also examined interactions with cue-based expectations about noxious stimulation, or stimulus expectancy. Results Pain was additively influenced by treatment expectancy, stimulus expectancy, and drug concentration. Attention performance showed a small but significant interaction between drug and treatment expectancy. Finally, remifentanil enhanced responses to both positive and negative emotional images. Conclusions The pain-relieving effects of opioid drugs are unlikely to be mediated by changes in threat or affective processing. Standard open-label opioid administration influences multiple clinically relevant cognitive and emotional processes. Psychological factors can combine with drug effects to influence multiple outcomes in distinct ways. The influence of specific psychological factors should be considered when developing and testing pharmacological treatments. PMID:24096537

  4. Parental bonds in children at high and low familial risk for panic disorder.

    PubMed

    Koszycki, Diana; Bilodeau, Cynthia; Zwanzger, Peter; Schneider, Barry H; Flament, Martine F; Bradwejn, Jacques

    2013-04-01

    A rejecting and overprotective parenting style is considered to be an important risk factor for the development of anxiety disorders. This study examined the role of perceived parental bonding as a potential environmental risk factor for panic disorder (PD) in unaffected offspring with parental PD. Children with a biological parent with PD (n = 71) and children of parents with no psychiatric history (n = 80) participated in the study. Results indicate that high risk children do not perceive their parents as being more protective and less caring than low risk controls. The optimal bonding type (high care, low protection) was the most frequently reported parenting style across groups. The constraining type of maternal bonding (high care, high protection) was less frequently reported by high risk children (p < 0.05). Overall, these data suggest that parental PD does not compromise the parent-child bonds in never-ill offspring.

  5. Interactions of School Bonding, Disturbed Family Relationships, and Risk Behaviors among Adolescents

    ERIC Educational Resources Information Center

    Rovis, Darko; Bezinovic, Petar; Basic, Josipa

    2015-01-01

    Background: Substance use, gambling, and violence represent a great risk for adolescent health. Schools are often referred to as the "best" places for health promotion and prevention, where positive school bonding serves as a strong protective factor for the development of risk behaviors and poor school bonding is associated with various…

  6. Study on the factors affecting the quality of public bus transportation service in Bali Province using factor analysis

    NASA Astrophysics Data System (ADS)

    Susilawati, M.; Nilakusmawati, D. P. E.

    2017-06-01

    The volume of mobility flows are increasing day by day and the condition of the number of people using private transport modes contribute to traffic congestion. With the limited capacity of the road, one of the alternatives solution to reduce congestion is to optimize the use of public transport. The purposes of this study are to determine the factors that influence user’s satisfaction on the quality of public bus transportation service and determine variables that became identifier on the dominant factor affecting user’s satisfaction. The study was conducted for the public bus transportation between districts in the province of Bali, which is among the eight regencies and one municipality, using a questionnaire as a data collection instrument. Service variables determinant of user’s satisfaction in this study, described in 25 questions, which were analyzed using factor analysis. The results showed there were six factors that explain the satisfaction of users of public transport in Bali, with a total diversity of data that can be parsed by 61.436%. These factors are: Safety and comfort, Responsiveness, Capacity, Tangible, Safety, Reliability. The dominant factor affecting public transport user satisfaction is the safety and comfort, with the most influential variable is feeling concerned about the personal safety of users when on the bus.

  7. A study of factors affecting the adoption of server virtualization technology

    NASA Astrophysics Data System (ADS)

    Lu, Hsin-Ke; Lin, Peng-Chun; Chiang, Chang-Heng; Cho, Chien-An

    2018-04-01

    It has become a trend that worldwide enterprises and organizations apply new technologies to improve their operations; besides, it has higher cost and less flexibility to construct and manage traditional servers, therefore the current mainstream is to use server virtualization technology. However, from these new technology organizations will not necessarily get the expected benefits because each one has its own level of organizational complexity and abilities to accept changes. The researcher investigated key factors affecting the adoption of virtualization technology through two phases. In phase I, the researcher reviewed literature and then applied the dimensions of "Information Systems Success Model" (ISSM) to generalize the factors affecting the adoption of virtualization technology to be the preliminary theoretical framework and develop a questionnaire; in phase II, a three-round Delphi Method was used to integrate the opinions of experts from related fields which were then gradually converged in order to obtain a stable and objective questionnaire of key factors so that these results were expected to provide references for organizations' adoption of server virtualization technology and future studies.

  8. Factors Affecting Environmental Knowledge and Attitudes among Lebanese College Students

    ERIC Educational Resources Information Center

    Oweini, Ahmad; Houri, Ahmad

    2006-01-01

    This exploratory study aimed at assessing the variables that would positively affect the knowledge and attitude of a group of Lebanese college students regarding the environment, namely such factors as gender, age, previous hiking experience and living abroad. A purposeful sample of students attending the Lebanese American University, was asked to…

  9. Factors Affecting Performance of Undergraduate Students in Construction Related Disciplines

    ERIC Educational Resources Information Center

    Olatunji, Samuel Olusola; Aghimien, Douglas Omoregie; Oke, Ayodeji Emmanuel; Olushola, Emmanuel

    2016-01-01

    Academic performance of students in Nigerian institutions has been of much concern to all and sundry hence the need to assess the factors affecting performance of undergraduate students in construction related discipline in Nigeria. A survey design was employed with questionnaires administered on students in the department of Quantity Surveying,…

  10. Formation of Irreversible H-bonds in Cellulose Materials

    Treesearch

    Umesh P. Agarwal; Sally A. Ralph; Rick S. Reiner; Nicole M. Stark

    2015-01-01

    Understanding of formation of irreversible Hbonds in cellulose is important in a number of fields. For example, fields as diverse as pulp and paper and enzymatic saccharification of cellulose are affected. In the present investigation, the phenomenon of formation of irreversible H-bonds is studied in a variety of celluloses and under two different drying conditions....

  11. Factors affecting the implementation of childhood vaccination communication strategies in Nigeria: a qualitative study.

    PubMed

    Oku, Afiong; Oyo-Ita, Angela; Glenton, Claire; Fretheim, Atle; Eteng, Glory; Ames, Heather; Muloliwa, Artur; Kaufman, Jessica; Hill, Sophie; Cliff, Julie; Cartier, Yuri; Bosch-Capblanch, Xavier; Rada, Gabriel; Lewin, Simon

    2017-02-15

    The role of health communication in vaccination programmes cannot be overemphasized: it has contributed significantly to creating and sustaining demand for vaccination services and improving vaccination coverage. In Nigeria, numerous communication approaches have been deployed but these interventions are not without challenges. We therefore aimed to explore factors affecting the delivery of vaccination communication in Nigeria. We used a qualitative approach and conducted the study in two states: Bauchi and Cross River States in northern and southern Nigeria respectively. We identified factors affecting the implementation of communication interventions through interviews with relevant stakeholders involved in vaccination communication in the health services. We also reviewed relevant documents. Data generated were transcribed verbatim and analysed using thematic analysis. We used the SURE framework to organise the identified factors (barriers and facilitators) affecting vaccination communication delivery. We then grouped these into health systems and community level factors. Some of the commonly reported health system barriers amongst stakeholders interviewed included: funding constraints, human resource factors (health worker shortages, training deficiencies, poor attitude of health workers and vaccination teams), inadequate infrastructure and equipment and weak political will. Community level factors included the attitudes of community stakeholders and of parents and caregivers. We also identified factors that appeared to facilitate communication activities. These included political support, engagement of traditional and religious institutions and the use of organised communication committees. Communication activities are a crucial element of immunization programmes. It is therefore important for policy makers and programme managers to understand the barriers and facilitators affecting the delivery of vaccination communication so as to be able to implement

  12. Effect of cleaning methods after reduced-pressure air abrasion on bonding to zirconia ceramic.

    PubMed

    Attia, Ahmed; Kern, Matthias

    2011-12-01

    To evaluate in vitro the influence of different cleaning methods after low-pressure air abrasion on the bond strength of a phosphate monomer-containing luting resin to zirconia ceramic. A total of 112 zirconia ceramic disks were divided into 7 groups (n = 16). In the test groups, disks were air abraded at low pressure (L) 0.05 MPa using 50-μm alumina particles. Prior to bonding, the disks were ultrasonically (U) cleaned either in isopropanol alcohol (AC), hydrofluoric acid (HF), demineralized water (DW), or tap water (TW), or they were used without ultrasonic cleaning. Disks air abraded at a high (H) pressure of 0.25 MPa and cleaned ultrasonically in isopropanol served as positive control; original (O) milled disks used without air abrasion served as the negative control group. Plexiglas tubes filled with composite resin were bonded with the adhesive luting resin Panavia 21 to the ceramic disks. Prior to testing tensile bond strength (TBS), each main group was further subdivided into 2 subgroups (n=8) which were stored in distilled water either at 37°C for 3 days or for 30 days with 7500 thermal cycles. Statistical analyses were conducted with two- and one-way analyses of variance (ANOVA) and Tukey's HSD test. Initial tensile bond strength (TBS) ranged from 32.6 to 42.8 MPa. After 30 days storage in water with thermocycling, TBS ranged from 21.9 to 36.3 MPa. Storage in water and thermocycling significantly decreased the TBS of test groups which were not air abraded (p = 0.05) or which were air abraded but cleaned in tap water (p = 0.002), but not the TBS of the other groups (p > 0.05). Also, the TBS of air-abraded groups were significantly higher than the TBS of the original milled (p < 0.01). Cleaning procedures did not significantly affect TBS either after 3 days or 30 days storage in water and thermocycling (p > 0.05). Air abrasion at 0.05 MPa and ultrasonic cleaning are important factors for improving bonding to zirconia ceramic.

  13. Factors affecting early and long-term outcomes after completion pneumonectomy.

    PubMed

    Chataigner, Olivier; Fadel, Elie; Yildizeli, Bedrettin; Achir, Abdallah; Mussot, Sacha; Fabre, Dominique; Mercier, Olaf; Dartevelle, Philippe G

    2008-05-01

    To identify factors that affect operative mortality and morbidity and long-term survival after completion pneumonectomy. We retrospectively reviewed the charts of consecutive patients who underwent completion pneumonectomy at our cardiothoracic surgery department from January 1996 to December 2005. We identified 69 patients, who accounted for 17.8% of all pneumonectomies during the study period; 22 had benign disease and 47 malignant disease (second primary lung cancer, n=19; local recurrence, n=17; or metastasis, n=11). There were 50 males and 19 females with a mean age of 60 years (range, 29-80 years). Postoperative mortality was 12% and postoperative morbidity 41%. Factors associated with postoperative mortality included obesity (p=0.005), coronary artery disease (p=0.03), removal of the right lung (p=0.02), advanced age (p=0.02), and renal failure (p<0.0001). Preoperative renal failure was the only significant risk factor for mortality by multivariate analysis (p=0.036). Bronchopleural fistula developed in seven patients (10%), with risk factors being removal of the right lung (p=0.04) and mechanical stump closure (p=0.03). Overall survival was 65% after 3 years and 46% after 5 years. Long-term survival was not affected by the reason for completion pneumonectomy. Although long-term survival was acceptable, postoperative mortality and morbidity rates remained high, confirming the reputation of completion pneumonectomy as a challenging procedure. Significant comorbidities and removal of the right lung were the main risk factors for postoperative mortality. Improved patient selection and better management of preoperative renal failure may improve the postoperative outcomes of this procedure, which offers a chance for prolonged survival.

  14. Bonding properties and bond activation of ylides: recent findings and outlook.

    PubMed

    Urriolabeitia, Esteban P

    2008-11-14

    The interaction of phosphorus and nitrogen ylides with metallic precursors has been examined from different points of view. The first one is related to the bonding properties of the ylides. Ylides with a unique stabilizing group bond through different atoms (the Calpha or the heteroatoms); while ylides with two stabilizing groups never coordinate through the Calpha atom. In the second section we examine the cause of the stereoselective coordination of bisylides of phosphorus, nitrogen and arsenic, and of mixed bisylides. We describe here the very interesting conformational preferences found in these systems, which have been determined and characterized. The DFT study of these bisylides has allowed for the characterization of strong intramolecular PO and AsO interactions, as well as moderate CHO[double bond, length as m-dash]C hydrogen bonds as the source of these conformational preferences. The third topic is related to the amazing reactivity of phosphorus ylides in bond activation processes. Depending on the nature of the metallic precursors, ylides can behave as sources of carbenes, of phosphine derivatives, of other ylides or of orthometallated complexes through P[double bond, length as m-dash]C, P-C or C-H bond activation reactions.

  15. Halogen bonding based recognition processes: a world parallel to hydrogen bonding.

    PubMed

    Metrangolo, Pierangelo; Neukirch, Hannes; Pilati, Tullio; Resnati, Giuseppe

    2005-05-01

    Halogen bonding is the noncovalent interaction between halogen atoms (Lewis acids) and neutral or anionic Lewis bases. The main features of the interaction are given, and the close similarity with the hydrogen bonding will become apparent. Some heuristic principles are presented to develop a rational crystal engineering based on halogen bonding. The focus is on halogen-bonded supramolecular architectures given by halocarbons. The potential of the interaction is shown by useful applications in the field of synthetic chemistry, material science, and bioorganic chemistry.

  16. Shear bond resistance and enamel surface comparison after the bonding and debonding of ceramic and metallic brackets

    PubMed Central

    da Rocha, José Maurício; Gravina, Marco Abdo; Campos, Marcio José da Silva; Quintão, Cátia Cardoso Abdo; Elias, Carlos Nelson; Vitral, Robert Willer Farinazzo

    2014-01-01

    Objective To evaluate, in vitro, the shear bond strength presented by three brands of polycrystalline ceramic brackets and one brand of metallic bracket; verify the adhesive remnant index (ARI) after the tests, and analyze, through scanning electron microscopy (SEM) the enamel surface topography after debonding, detecting the release of mineral particles. Methods Sixty bovine lower incisors were used. Three ceramic brackets (Allure®, InVu®, and Clarity®) and one metallic bracket (Geneus®) were bonded with Transbond XT®. Kruskal-Wallis's test (significance level set at 5%) was applied to the results of share bond and ARI. Mann Whitney's test was performed to compare the pairs of brackets in relation to their ARI. Brown-Forsythe's test (significance level set at 5%) was applied to the results of enamel chemical composition. Comparisons between groups were made with Games-Howell's and the Post-hoc tests. Results No statistically significant difference was observed in relation to the shear bond strength loads. Clarity® brackets were the most affected in relation to the surface topography and to the release of mineral particles of enamel (calcium ions). Conclusion With regard to the ARI, there was a prevalence of score 4 (40.4%). As for enamel surface topography, the Geneus® bracket was the only one which did not show superficial tissue loss. The InVu® and Clarity® ones showed cohesive fractures in 33.3% and the Allure® in 50%, the latter being the one that presented most fractures during removal. PMID:24713563

  17. Closing in on Chemical Bonds by Opening up Relativity Theory

    PubMed Central

    Whitney, Cynthia Kolb

    2008-01-01

    This paper develops a connection between the phenomenology of chemical bonding and the theory of relativity. Empirical correlations between electron numbers in atoms and chemical bond stabilities in molecules are first reviewed and extended. Quantitative chemical bond strengths are then related to ionization potentials in elements. Striking patterns in ionization potentials are revealed when the data are viewed in an element-independent way, where element-specific details are removed via an appropriate scaling law. The scale factor involved is not explained by quantum mechanics; it is revealed only when one goes back further, to the development of Einstein’s special relativity theory. PMID:19325749

  18. Metal-Free Oxidative C-C Bond Formation through C-H Bond Functionalization.

    PubMed

    Narayan, Rishikesh; Matcha, Kiran; Antonchick, Andrey P

    2015-10-12

    The formation of C-C bonds embodies the core of organic chemistry because of its fundamental application in generation of molecular diversity and complexity. C-C bond-forming reactions are well-known challenges. To achieve this goal through direct functionalization of C-H bonds in both of the coupling partners represents the state-of-the-art in organic synthesis. Oxidative C-C bond formation obviates the need for prefunctionalization of both substrates. This Minireview is dedicated to the field of C-C bond-forming reactions through direct C-H bond functionalization under completely metal-free oxidative conditions. Selected important developments in this area have been summarized with representative examples and discussions on their reaction mechanisms. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. 30 CFR 281.33 - Bonds and bonding requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Bonds and bonding requirements. 281.33 Section 281.33 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE LEASING OF MINERALS OTHER THAN OIL, GAS, AND SULPHUR IN THE OUTER CONTINENTAL SHELF Financial Considerations § 281.33...

  20. Factors Affecting 25-Hydroxyvitamin D Concentration in Response to Vitamin D Supplementation

    PubMed Central

    Mazahery, Hajar; von Hurst, Pamela R.

    2015-01-01

    Sun exposure is the main source of vitamin D. Due to many lifestyle risk factors vitamin D deficiency/insufficiency is becoming a worldwide health problem. Low 25(OH)D concentration is associated with adverse musculoskeletal and non-musculoskeletal health outcomes. Vitamin D supplementation is currently the best approach to treat deficiency and to maintain adequacy. In response to a given dose of vitamin D, the effect on 25(OH)D concentration differs between individuals, and it is imperative that factors affecting this response be identified. For this review, a comprehensive literature search was conducted to identify those factors and to explore their significance in relation to circulating 25(OH)D response to vitamin D supplementation. The effect of several demographic/biological factors such as baseline 25(OH)D, aging, body mass index(BMI)/body fat percentage, ethnicity, calcium intake, genetics, oestrogen use, dietary fat content and composition, and some diseases and medications has been addressed. Furthermore, strategies employed by researchers or health care providers (type, dose and duration of vitamin D supplementation) and environment (season) are other contributing factors. With the exception of baseline 25(OH)D, BMI/body fat percentage, dose and type of vitamin D, the relative importance of other factors and the mechanisms by which these factors may affect the response remains to be determined. PMID:26121531

  1. Factors Affecting Aerosol Radiative Forcing

    NASA Astrophysics Data System (ADS)

    Wang, Jingxu; Lin, Jintai; Ni, Ruijing

    2016-04-01

    Rapid industrial and economic growth has meant a large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RF of aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissions per unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size. South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions, its aerosol RF is alleviated by its lowest chemical efficiency. The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is lowered by a small per capita GDP. Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The

  2. Factors Affecting Aerosol Radiative Forcing

    NASA Astrophysics Data System (ADS)

    Wang, J.; Lin, J.; Ni, R.

    2016-12-01

    Rapid industrial and economic growth has meant large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RFof aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissionsper unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size.South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions,its aerosol RF is alleviated by its lowest chemical efficiency.The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is loweredbyasmall per capita GDP.Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The resulting

  3. Solder extrusion pressure bonding process and bonded products produced thereby

    DOEpatents

    Beavis, Leonard C.; Karnowsky, Maurice M.; Yost, Frederick G.

    1992-01-01

    Production of soldered joints which are highly reliable and capable of surviving 10,000 thermal cycles between about -40.degree. C. and 110.degree. C. Process involves interposing a thin layer of a metal solder composition between the metal surfaces of members to be bonded and applying heat and up to about 1000 psi compression pressure to the superposed members, in the presence of a reducing atmosphere, to extrude the major amount of the solder composition, contaminants including fluxing gases and air, from between the members being bonded, to form a very thin, strong intermetallic bonding layer having a thermal expansion tolerant with that of the bonded members.

  4. Solder extrusion pressure bonding process and bonded products produced thereby

    NASA Astrophysics Data System (ADS)

    Beavis, L. C.; Karnowsky, M. M.; Yost, F. G.

    1990-04-01

    The production of soldered joints are highly reliable and capable of surviving 10,000 thermal cycles between about -40 and 110 C. The process involves interposing a thin layer of a metal solder composition between the metal surfaces of members to be bonded and applying heat up to about 1000 psi compression pressure to the superposed members, in the presence of a reducing atmosphere, to extrude the major amount of the solder composition, contaminants including fluxing gases and air, from between the members being bonded, to form a very thin, strong intermetallic bonding layer having a thermal expansion tolerant with that of the bonded members.

  5. Mothers recovering from cocaine addiction: factors affecting parenting skills.

    PubMed

    Coyer, S M

    2001-01-01

    To identify factors that may influence parenting by mothers who are recovering from cocaine addiction. Exploratory descriptive, with in-depth unstructured interviews. Interviews were conducted in the woman's home or in a treatment center. A convenience sample of 11 women recovering from cocaine addiction who were mothers of children 3 years of age and younger. A content analysis was used to analyze the interview data. Two themes, personal/psychologic factors and environmental/contextual factors, and four subthemes emerged. They identify issues that may affect parenting by mothers being treated for cocaine addiction. Subthemes included low self-esteem, difficulty developing a maternal identity, isolation from friends and family, and chronic life stress. This study provides a better understanding of the sources contributing to vulnerability in the parenting role for mothers recovering from cocaine addiction and will assist nurses in providing care for these mothers and their children.

  6. The significance of nanoparticles on bond strength of polymer concrete to steel

    DOE PAGES

    Douba, A.; Genedy, M.; Matteo, E. N.; ...

    2017-01-03

    Here, polymer concrete (PC) is a commonly used material in construction due to its improved durability and good bond strength to steel substrate. PC has been suggested as a repair and seal material to restore the bond between the cement annulus and the steel casing in wells that penetrate formations under consideration for CO 2 sequestration. Nanoparticles including Multi-Walled Carbon Nano Tubes (MWCNTs), Aluminum Nanoparticles (ANPs) and Silica Nano particles (SNPs) were added to an epoxy-based PC to examine how the nanoparticles affect the bond strength of PC to a steel substrate. Slant shear tests were used to determine themore » bond strength of PC incorporating nanomaterials to steel; results reveal that PC incorporating nanomaterials has an improved bond strength to steel substrate compared with neat PC. In particular, ANPs improve the bond strength by 51% over neat PC. Local shear stresses, extracted from Finite Element (FE) analysis of the slant shear test, were found to be as much as twice the apparent/average shear/bond strength. These results suggest that the impact of nanomaterials is higher than that shown by the apparent strength. Fourier Transform Infrared (FTIR) measurements of epoxy with and without nanomaterials showed ANPs to influence curing of epoxy, which might explain the improved bond strength of PC incorporating ANPs.« less

  7. The significance of nanoparticles on bond strength of polymer concrete to steel

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

    Douba, A.; Genedy, M.; Matteo, E. N.

    Here, polymer concrete (PC) is a commonly used material in construction due to its improved durability and good bond strength to steel substrate. PC has been suggested as a repair and seal material to restore the bond between the cement annulus and the steel casing in wells that penetrate formations under consideration for CO 2 sequestration. Nanoparticles including Multi-Walled Carbon Nano Tubes (MWCNTs), Aluminum Nanoparticles (ANPs) and Silica Nano particles (SNPs) were added to an epoxy-based PC to examine how the nanoparticles affect the bond strength of PC to a steel substrate. Slant shear tests were used to determine themore » bond strength of PC incorporating nanomaterials to steel; results reveal that PC incorporating nanomaterials has an improved bond strength to steel substrate compared with neat PC. In particular, ANPs improve the bond strength by 51% over neat PC. Local shear stresses, extracted from Finite Element (FE) analysis of the slant shear test, were found to be as much as twice the apparent/average shear/bond strength. These results suggest that the impact of nanomaterials is higher than that shown by the apparent strength. Fourier Transform Infrared (FTIR) measurements of epoxy with and without nanomaterials showed ANPs to influence curing of epoxy, which might explain the improved bond strength of PC incorporating ANPs.« less

  8. Factors Affecting the Interest of Israeli Social Work Students in Working with Different Client Groups

    ERIC Educational Resources Information Center

    Krumer-Nevo, Michal; Weiss, Idit

    2006-01-01

    Employing a large-scale sample of 521 BSW students from 4 Israeli schools of social work, this research examines the factors affecting social work students' interest in working with a wide range of client groups. The results suggest that student interest in working with specific client groups is affected by factors related to desire for…

  9. Factors Affecting English Language Teaching and Learning in Higher Education

    ERIC Educational Resources Information Center

    Nguyen, Hong Thi; Warren, Wendy; Fehring, Heather

    2014-01-01

    This paper reports part of a study that aims to explore factors affecting the efficacy of non-major English teaching and learning in Vietnamese higher education through an investigation of classroom practices. Eight non-participant class observations were conducted at HUTECH University, Ho Chi Minh City, Vietnam. The study's findings show that…

  10. The Impact of CLIL on Affective Factors and Vocabulary Learning

    ERIC Educational Resources Information Center

    Heras, Arantxa; Lasagabaster, David

    2015-01-01

    The aim of this article is twofold: to assess the effectiveness of a CLIL (content and language integrated learning) module on affective factors (motivation and self-esteem), and to test the purported blurring effect of CLIL on gender differences in foreign language learning. Forty-six students in their fourth year of compulsory secondary…

  11. The Perspective of Gozitan Teachers on Factors Affecting Students' Achievement

    ERIC Educational Resources Information Center

    Xuereb, Lorna; De Giovanni, Katya Sarah

    2016-01-01

    This study aims at exploring the impact of factors at pupil, teacher and school levels on students? academic achievement. Moreover, the main purpose was that of investigating which one of the three levels is most likely to affect students? educational accomplishment. A questionnaire was administered to 100 Gozitan teachers. Results were analysed…

  12. 77 FR 18862 - Brazil: Competitive Factors Affecting U.S. and Brazilian Agricultural Sales in Selected Third...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 332-524] Brazil: Competitive Factors Affecting U.S. and Brazilian Agricultural Sales in Selected Third Country Markets AGENCY: United States... Committee in investigation No. 332-524, Brazil: Competitive Factors In Brazil Affecting U.S. and Brazilian...

  13. Insertion reactions into Pd[bond]O and Pd[bond]N bonds: preparation of alkoxycarbonyl, carbonato, carbamato, thiocarbamate, and thioureide complexes of palladium(II).

    PubMed

    Ruiz, José; Martínez, M Teresa; Florenciano, Félix; Rodríguez, Venancio; López, Gregorio; Pérez, José; Chaloner, Penny A; Hitchcock, Peter B

    2003-06-02

    Mononuclear palladium hydroxo complexes of the type [Pd(N[bond]N)(C(6)F(5))(OH)] [(N[bond]N = 2,2'-bipyridine (bipy), 4,4'-dimethyl-2,2'-bipyridine (Me(2)bipy), 1,10-phenanthroline (phen), or N,N,N',N'-tetramethylethylenediamine (tmeda)] have been prepared by reaction of [Pd(N[bond]N)(C(6)F(5))(acetone)]ClO(4) with KOH in methanol. These hydroxo complexes react, in methanol, with CO (1 atm, room temperature) to yield the corresponding methoxycarbonyl complexes [Pd(N[bond]N)(C(6)F(5))(CO(2)Me)]. Similar alkoxycarbonyl complexes [Pd(N[bond]N)(C(6)F(5))(CO(2)R)] (N[bond]N = bis(3,5-dimethylpyrazol-1-yl)methane); R = Me, Et, or (i)Pr) are obtained when [Pd(N[bond]N)(C(6)F(5))Cl] is treated with KOH in the corresponding alcohol ROH and CO is bubbled through the solution. The reactions of [Pd(N[bond]N)(C(6)F(5))(OH)] (N[bond]N = bipy or Me(2)bipy) with CO(2), in tetrahydrofuran, lead to the formation of the binuclear carbonate complexes [(N[bond]N)(C(6)F(5))Pd(mu-eta(2)-CO(3))Pd(C(6)F(5))(N[bond]N)]. Complexes [Pd(N[bond]N)(C(6)F(5))(OH)] react in alcohol with PhNCS to yield the corresponding N-phenyl-O-alkylthiocarbamate complexes [Pd(N[bond]N)(C(6)F(5))[SC(OR)NPh

  14. Longitudinal evaluation of the microleakage of dentin bonding agents used to seal resected root apices.

    PubMed

    Vignaroli, P A; Anderson, R W; Pashley, D H

    1995-10-01

    A material that bonds to dentin and seals both the root canal and exposed dentinal tubules would be desirable following root resection. The purpose of this study was to measure the sealing ability of four dentin bonding agents on the resected root end. The bonding systems evaluated were Amalgambond (AMB), Scotchbond Multi-Purpose (SMP), Prisma Universal Bond 3 (PUB 3), and All-Bond 2 (AB2). All materials were applied directly to the resected root end without a class I preparation. One-half of the roots in each group were contaminated with human blood before bonding. Microleakage was measured using fluid filtration at various time intervals from 1 to 24 wk. Results indicated that all dentin bonding agents significantly reduced apical microleakage compared with prebonded controls at all time intervals. Blood contamination did not adversely affect the sealing ability of AMB, PUB 3, or SMP. The blood-contaminated AB2 group displayed significantly greater microleakage after 12 and 24 wk than the uncontaminated roots.

  15. Bonding strength of alkyl-2-cyanoacrylates to bone in vitro.

    PubMed

    Kilpikari, J; Lapinsuo, M; Törmälä, P; Pätiälä, H; Rokkanen, P

    1986-10-01

    This study measured the bonding strength between alkyl-2-cyanoacrylates and bone, and examined how treatment of the bone surface with acid, and prolonged exposure to moisture, affected this strength. The initial strength of all cyanoacrylates was high (9.6-11.2 N/mm2). In long-term experiments under water, n- and i-butylcyanoacrylates lost their strength at a far slower rate than ethylcyanoacrylates. However, the butylcyanoacrylates also showed a decrease of 15% in strength after three weeks. Pretreatment of the bone surface with acid did not have a marked effect on bonding strength, although SEM investigation revealed that the acid treatment had increased the porosity of the bone surface. A study of the fracture surface proved that the adhesive film tended to loosen or break after 3 to 6 weeks under water. The decrease in the bonding strength was probably due to the degradation of the adhesive film in water which loosened mechanical bonds between the bone and adhesive. Considering clinical use it would be necessary to achieve better long-term strength.

  16. Hydrogen bonding in ionic liquids.

    PubMed

    Hunt, Patricia A; Ashworth, Claire R; Matthews, Richard P

    2015-03-07

    Ionic liquids (IL) and hydrogen bonding (H-bonding) are two diverse fields for which there is a developing recognition of significant overlap. Doubly ionic H-bonds occur when a H-bond forms between a cation and anion, and are a key feature of ILs. Doubly ionic H-bonds represent a wide area of H-bonding which has yet to be fully recognised, characterised or explored. H-bonds in ILs (both protic and aprotic) are bifurcated and chelating, and unlike many molecular liquids a significant variety of distinct H-bonds are formed between different types and numbers of donor and acceptor sites within a given IL. Traditional more neutral H-bonds can also be formed in functionalised ILs, adding a further level of complexity. Ab initio computed parameters; association energies, partial charges, density descriptors as encompassed by the QTAIM methodology (ρBCP), qualitative molecular orbital theory and NBO analysis provide established and robust mechanisms for understanding and interpreting traditional neutral and ionic H-bonds. In this review the applicability and extension of these parameters to describe and quantify the doubly ionic H-bond has been explored. Estimating the H-bonding energy is difficult because at a fundamental level the H-bond and ionic interaction are coupled. The NBO and QTAIM methodologies, unlike the total energy, are local descriptors and therefore can be used to directly compare neutral, ionic and doubly ionic H-bonds. The charged nature of the ions influences the ionic characteristics of the H-bond and vice versa, in addition the close association of the ions leads to enhanced orbital overlap and covalent contributions. The charge on the ions raises the energy of the Ylp and lowers the energy of the X-H σ* NBOs resulting in greater charge transfer, strengthening the H-bond. Using this range of parameters and comparing doubly ionic H-bonds to more traditional neutral and ionic H-bonds it is clear that doubly ionic H-bonds cover the full range of weak

  17. Postpartum bonding: the role of perinatal depression, anxiety and maternal-fetal bonding during pregnancy.

    PubMed

    Dubber, S; Reck, C; Müller, M; Gawlik, S

    2015-04-01

    Adverse effects of perinatal depression on the mother-child interaction are well documented; however, the influence of maternal-fetal bonding during pregnancy on postpartum bonding has not been clearly identified. The subject of this study was to investigate prospectively the influence of maternal-fetal bonding and perinatal symptoms of anxiety and depression on postpartum mother-infant bonding. Data from 80 women were analyzed for associations of symptoms of depression and anxiety as well as maternal bonding during pregnancy to maternal bonding in the postpartum period using the Edinburgh Postnatal Depression Scale (EPDS), the State-Trait Anxiety Inventory (STAI), the Pregnancy Related Anxiety Questionnaire (PRAQ-R), the Maternal-Fetal Attachment Scale (MFAS) and the Postpartum Bonding Questionnaire (PBQ-16). Maternal education, MFAS, PRAQ-R, EPDS and STAI-T significantly correlated with the PBQ-16. In the final regression model, MFAS and EPDS postpartum remained significant predictors of postpartum bonding and explained 20.8 % of the variance. The results support the hypothesized negative relationship between maternal-fetal bonding and postpartum maternal bonding impairment as well as the role of postpartum depressive symptoms. Early identification of bonding impairment during pregnancy and postpartum depression in mothers plays an important role for the prevention of potential bonding impairment in the early postpartum period.

  18. Micro-CT evaluation of microleakage under orthodontic ceramic brackets bonded with different bonding techniques and adhesives.

    PubMed

    Öztürk, Fırat; Ersöz, Mustafa; Öztürk, Seyit Ahmet; Hatunoğlu, Erdem; Malkoç, Sıddık

    2016-04-01

    The aim of this study was to evaluate microleakage under orthodontic ceramic brackets bonded with direct and different indirect bonding techniques and adhesives using micro-computed tomography. A total of 30 human maxillary premolars were randomly separated into five groups with six teeth in each group. In group I, teeth were bonded directly with Transbond XT (3M Unitek). In group II, group III, group IV, and group V, teeth were bonded through an indirect technique with Custom I.Q. (Reliance Orthodontic Products), Sondhi Rapid-Set (3M Unitek), RMbond (RMO), and Transbond IDB (3M Unitek), respectively, following the manufacturer's instructions. Micro-CT system model 1172 of Skyscan (Kontich, Belgium) was used to scan all samples. NRecon (Skyscan) version 1.6, CT-Analyser V.1.11 (Skyscan), and TView (SkyScan, Bvba) software programs were used for microleakage evaluation. Microleakage values between the test groups were assessed using the Kruskal-Wallis test, while the Wilcoxon signed rank test was used for within-group comparisons. The level of significance was set at P < 0.05. According to the Kruskal-Wallis analysis of variance test, there were no significant differences among the tested groups, with regard to volume and percentage (microleakage/region of interest × 100) of microleakage values (P < 0.05). The Wilcoxon signed rank test showed that coronal microleakage volume and percentage values significantly differed for RMbond and Transbond IDB groups. In the study, only ceramic brackets were used and microleakage into mini gaps did not show up on the micro-CT image because 50% silver nitrate solution could not penetrate into mini gaps which are smaller than silver nitrate particles. Use of direct and indirect bonding techniques with different adhesives did not significantly affect the amount of microleakage. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email

  19. Factors affecting the stability of reverse shoulder arthroplasty: a biomechanical study.

    PubMed

    Clouthier, Allison L; Hetzler, Markus A; Fedorak, Graham; Bryant, J Tim; Deluzio, Kevin J; Bicknell, Ryan T

    2013-04-01

    Despite the success of reverse shoulder arthroplasty (RSA) in treating patients with painful pseudoparalytic shoulders, instability is a common complication and currently the factors affecting stability are not well understood. The objective of this study was to investigate a number of factors as well as the interactions between factors to determine how they affect the stability of the prosthesis. These factors included: active arm posture (abduction and abduction plane angles), loading direction, glenosphere diameter and eccentricity, and humeral socket constraint. Force required to dislocate the joint, determined using a biomechanical shoulder simulator, was used as a measure of stability. A factorial design experiment was implemented to examine the factors and interactions. Actively increasing the abduction angle by 15° leads to a 30% increase in stability and use of an inferior-offset rather than a centered glenosphere improved stability by 17%. Use of a more constrained humeral socket also increased stability; but the effect was dependent on loading direction, with a 88% improvement for superior loading, 66% for posterior, 36% for anterior, and no change for inferior loading. Abduction plane angle and glenosphere diameter had no effect on stability. Increased glenohumeral abduction and the use of an inferior-offset glenosphere were found to increase the stability of RSA. Additionally, use of a more constrained humeral socket increased stability for anterior, posterior, and superior loading. These identified factor effects have the potential to decrease the risk of dislocation following RSA. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  20. Amino acid polymorphisms in the fibronectin-binding repeats of fibronectin-binding protein A affect bond strength and fibronectin conformation

    PubMed Central

    Casillas-Ituarte, Nadia N.; Cruz, Carlos H. B.; Lins, Roberto D.; DiBartola, Alex C.; Howard, Jessica; Liang, Xiaowen; Höök, Magnus; Viana, Isabelle F. T.; Sierra-Hernández, M. Roxana; Lower, Steven K.

    2017-01-01

    The Staphylococcus aureus cell surface contains cell wall-anchored proteins such as fibronectin-binding protein A (FnBPA) that bind to host ligands (e.g. fibronectin; Fn) present in the extracellular matrix of tissue or coatings on cardiac implants. Recent clinical studies have found a correlation between cardiovascular infections caused by S. aureus and nonsynonymous SNPs in FnBPA. Atomic force microscopy (AFM), surface plasmon resonance (SPR), and molecular simulations were used to investigate interactions between Fn and each of eight 20-mer peptide variants containing amino acids Ala, Asn, Gln, His, Ile, and Lys at positions equivalent to 782 and/or 786 in Fn-binding repeat-9 of FnBPA. Experimentally measured bond lifetimes (1/koff) and dissociation constants (Kd = koff/kon), determined by mechanically dissociating the Fn·peptide complex at loading rates relevant to the cardiovascular system, varied from the lowest-affinity H782A/K786A peptide (0.011 s, 747 μm) to the highest-affinity H782Q/K786N peptide (0.192 s, 15.7 μm). These atomic force microscopy results tracked remarkably well to metadynamics simulations in which peptide detachment was defined solely by the free-energy landscape. Simulations and SPR experiments suggested that an Fn conformational change may enhance the stability of the binding complex for peptides with K786I or H782Q/K786I (Kdapp = 0.2–0.5 μm, as determined by SPR) compared with the lowest-affinity double-alanine peptide (Kdapp = 3.8 μm). Together, these findings demonstrate that amino acid substitutions in Fn-binding repeat-9 can significantly affect bond strength and influence the conformation of Fn upon binding. They provide a mechanistic explanation for the observation of nonsynonymous SNPs in fnbA among clinical isolates of S. aureus that cause endovascular infections. PMID:28400484

  1. Factors affecting the palpability of breast lesion by self-examination.

    PubMed

    Lam, W W M; Chan, C P; Chan, C F; Mak, C C C; Chan, C F; Chong, K W H; Leung, M H J; Tang, M H

    2008-03-01

    This study aims to assess the accuracy of detection of breast lesion by breast self-examination and to assess different factors affecting the accuracy. All consecutive Chinese female patients, who attended our breast imaging unit in 2001, completed our questionnaire, had retrievable hard copy films, and had more than three years clinical follow-up, were recruited for this study. Different factors, such as age, menopausal status, previous experience of breastfeeding, family history of breast cancer, previous history of mastectomy or lumpectomy, hormonal therapy, oral contraceptive pills and previous history of mammography, were correlated with accuracy in self-detection of breast lesions retrospectively. The nature, size and location of the lesion, and breast size based on imaging, were also correlated with the accuracy in self-detection of breast lesions. A total of 163 questionnaires were analysed. 111 patients detected a breast lesion themselves and 24 of these lesions were false-positives. A total of 173 lesions (27 cancerous, 146 benign lesions) were documented by either ultrasonography and/or mammography, and confirmed by either histology or three-year clinical follow-up. The overall sensitivity in detecting both benign and malignant breast lesions was 71% when number of breast lesions was used as the denominator, and up to 78% sensitivity was achieved when number of patients was used as the denominator. History of mastectomy, and size and nature of the lesions were found to affect the accuracy of self-detection of breast lesions. Overall, breast self-examinations were effective in the detection of breast lesions and factors such as size of lesion, nature of the lesion and history of mastectomy affect the accuracy of the detections. Breast self-examination should be promoted for early detection of breast cancer.

  2. Factors Affecting the Effectiveness and Use of Moodle: Students' Perception

    ERIC Educational Resources Information Center

    Damnjanovic, Vesna; Jednak, Sandra; Mijatovic, Ivana

    2015-01-01

    The purpose of this research paper is to identify the factors affecting the effectiveness of Moodle from the students' perspective. The research hypotheses derived from the suggested extended Seddon model have been empirically validated using the responses to a survey on e-learning usage among 255 users. We tested the model across higher education…

  3. The Effect on Final Bond Strength of Bracket Manipulation Subsequent To Initial Positioning

    NASA Astrophysics Data System (ADS)

    Beebe, David A.

    The shear bond strength of light activated orthodontic adhesives varies according to the composition of the material, placement protocol, and time prior to light curing. Manipulating brackets after their initial placement on a tooth can disrupt the adhesive's polymerization and compromise final bond strength. No previous research has investigated how a specific degree of manipulation, and the amount of time elapsed prior to curing, under specific lighting conditions, affects the orthodontic adhesives shear bond strength. Victory SeriesRTM, MBT prescription, premolar (3M Unitek, Monrovia, CA) orthodontic brackets were bonded using three different adhesives to sixty (60) bicuspids and varying the time after bracket manipulation before curing. The shear bond strength was calculated for each specimen. The brackets were debonded and the same teeth were rebonded with new, identical brackets, using the same protocol and under the same conditions. The results showed a statistically significant difference between the shear bond strength of Transbond XT and Grengloo, with Transbond XT having the highest strength. There was also a statistically significance difference in bond strength between the group cured 30 seconds after manipulation and the groups manipulated at different intervals prior to curing, with the 30 second group having the highest bond strength. This study confirms that various orthodontic adhesives have different bond strengths depending on manipulation and varying times prior to curing each adhesive.

  4. Influence of drying time and temperature on bond strength of contemporary adhesives to dentine.

    PubMed

    Garcia, Fernanda C P; Almeida, Júlio C F; Osorio, Raquel; Carvalho, Ricardo M; Toledano, Manuel

    2009-04-01

    To evaluate the bond strength (microTBS) of self-etching adhesives in different solvent evaporation conditions. Flat dentine surfaces from extracted human third molars were bonded with: (1) 2 two-steps self-etching adhesives (Clearfil SE Bond-CSEB); (Protect Bond-PB) and (2) 2 one-step self-etch systems (Adper Prompt L Pop-ADPLP); (Xeno III-XIII). Bonded dentine surfaces were air-dried for 5s, 20s, 30s or 40s at either 21 degrees C or 38 degrees C. Composite build-ups were constructed incrementally. After storage in water for 24h at 37 degrees C, the specimens were prepared for microtensile bond strength testing. Data were analyzed by two-way ANOVA and Student-Newman-Keuls at alpha=0.05. CSEB and PB performed better at warm temperature with only 20s of air-blowing. The bond strength increased when XIII was performed at warm temperature at 40s air-blowing. Extended air-blowing not affect the performance of ADPLP, except at 30s air-blowing time at warm temperature. The use of a warm air-dry stream seems to be a clinical tool to improve the bond strength to self-etching adhesives.

  5. Solder extrusion pressure bonding process and bonded products produced thereby

    DOEpatents

    Beavis, L.C.; Karnowsky, M.M.; Yost, F.G.

    1992-06-16

    Disclosed is a process for production of soldered joints which are highly reliable and capable of surviving 10,000 thermal cycles between about [minus]40 C and 110 C. Process involves interposing a thin layer of a metal solder composition between the metal surfaces of members to be bonded and applying heat and up to about 1000 psi compression pressure to the superposed members, in the presence of a reducing atmosphere, to extrude the major amount of the solder composition, contaminants including fluxing gases and air, from between the members being bonded, to form a very thin, strong intermetallic bonding layer having a thermal expansion tolerant with that of the bonded members.

  6. Factors Affecting Conservation Practice Behavior of CRP Participants in Alabama

    Treesearch

    Okwudili Onianwa; Gerald Wheelock; Shannon Hendrix

    1999-01-01

    This study examines the factors that affect conservation practice choices of CRP farmers in Alabama. From over 9,000 contracts enrolled in the state between 1986 and 1995, 594 were randomly selected for the study. A multiple-regression analysis was employed to analyze the data. Results indicate that education, ratio ofcropland in CRP, farm size, gender, prior crop...

  7. Factors Affecting the Retention Decisions of Female Surface Warfare Officers

    DTIC Science & Technology

    2003-03-01

    NAVAL POSTGRADUATE SCHOOL Monterey, California THESIS Approved for public release; distribution is unlimited. FACTORS AFFECTING THE RETENTION...Warfare Officers 6. AUTHOR(S) Clifton, Elizabeth A. 5. FUNDING NUMBERS 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate School ...for the degree of MASTER OF SCIENCE IN LEADERSHIP AND HUMAN RESOURCE DEVELOPMENT from the NAVAL POSTGRADUATE SCHOOL March 2003

  8. The CRF system mediates increased passive stress-coping behavior following the loss of a bonded partner in a monogamous rodent.

    PubMed

    Bosch, Oliver J; Nair, Hemanth P; Ahern, Todd H; Neumann, Inga D; Young, Larry J

    2009-05-01

    Social relationships significantly influence physiology and behavior, including the hypothalamo-pituitary-adrenal axis, anxiety, and mental health. Disruption of social bonds through separation or death often results in profound grieving, depression, and physical illness. As the monogamous prairie vole forms enduring, selective pair bonds with the mating partner, they provide an animal model to study the physiological consequences of pair bonding and, thus, the loss of the bonded partner. Male prairie voles were paired with a novel female or male sibling. After 5 days, half of the males of each group were separated from the partner. Elevated plus-maze, forced swim, and tail suspension tests were used to assess anxiety-like and passive stress-coping behaviors indicative of depressive-like behavior. Following 4 days of separation from the female but not the male partner, experimental males displayed increased passive stress-coping. This effect was abolished by long-term intracerebroventricular infusion of a nonselective corticotropin-releasing factor (CRF) receptor antagonist without disrupting the bond itself. Both CRF type 1 and 2 receptors were involved in the emergence of passive stress-coping behavior. Furthermore, pairing with a female was associated with elevated CRF mRNA in the bed nucleus of the stria terminalis, and partner loss elicited a pronounced increase in circulating corticosteroid and adrenal weight. We speculate that the CRF system may mediate an aversive affect following separation from the female partner, which may facilitate proximity seeking between the pair-bonded individuals. Hence, the prairie vole model may provide insights into brain mechanisms involved in the psychopathological consequences of partner loss.

  9. Factors Affecting Lactoferrin Concentration in Human Milk: How Much Do We Know?

    PubMed Central

    Villavicencio, Aasith; Rueda, Maria S.; Turin, Christie G.; Ochoa, Theresa J.

    2017-01-01

    Lactoferrin (LF) is a breast milk glycoprotein with antimicrobial and anti-inflammatory effects. Its beneficial properties in infants, especially in those born preterm, are currently being studied in clinical trials. However, the maternal and nursing infant factors that may affect the concentration of LF in breast milk are still not clear. We conducted a systematic review to investigate the factors that may affect LF concentration. We used a 2-step approach to identify the eligible studies according to inclusion/exclusion criteria and to determine which studies would be considered. We included 70 qualified articles from 29 countries with publication dates ranging from 1976 to 2015. We described the correlation between LF concentration in breast milk and lactation stage; 10 maternal factors, such as race, parity, among others; and 2 infant factors, infections and prematurity. Colostrum has the highest LF levels, but they decrease with days postpartum. No other factor has been consistently associated with LF concentration. A major limitation of the majority of the published studies is the small sample size and the different methods used to measure LF concentration. Therefore, there is a need for large, multicenter studies with standardized study design, sample collection, and LF measurement methods to identify clinically significant factors associated with LF expression in breast milk, which will help promote exclusive breastfeeding in preterm infants. PMID:28075610

  10. Protective Factors against Serious Violent Behavior in Adolescence: A Prospective Study of Aggressive Children.

    ERIC Educational Resources Information Center

    Herrenkohl, Todd I.; Hill, Karl G.; Chung, Ick-Joong; Guo, Jie; Abbott, Robert D.; Hawkins, J. David

    2003-01-01

    Examines factors in adolescence that affect the probability of violent behavior at age 18 among youths who received high teacher ratings of aggression at age 10. Study found a lower probability of violence was associated with religious services attendance, good family management by parents, and bonding to school. Implications of these findings for…

  11. Factors affecting assertiveness among student nurses.

    PubMed

    Ibrahim, Sanaa Abd El Azim

    2011-05-01

    This study aimed to investigate the factors affecting assertiveness among student nurses. The study was carried out at Faculty of Nursing, Port-Said University, on 207 student nurses from four different grades. Rathus Assertiveness Schedule, consisted of 30 items, was used to measure the students' assertiveness level and a 12-item scale developed by Spreitzer was used to measure students' psychological empowerment. The study results showed that 60.4% of the students were assertive, while about half of the students were empowered. A positive relation between student assertiveness and psychological empowerment was detected. Moreover, positive relations regarding family income and students' assertiveness and psychological empowerment were determined. The study recommended introduction of specific courses aiming at enhancing the acquisition of assertiveness skills, in addition, nurse educators must motivate their students to express their opinion and personal rights and also they must pay attention for students' empowerment and enhance students' autonomy. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. Factors Affecting Regional Per-Capita Carbon Emissions in China Based on an LMDI Factor Decomposition Model

    PubMed Central

    Dong, Feng; Long, Ruyin; Chen, Hong; Li, Xiaohui; Yang, Qingliang

    2013-01-01

    China is considered to be the main carbon producer in the world. The per-capita carbon emissions indicator is an important measure of the regional carbon emissions situation. This study used the LMDI factor decomposition model–panel co-integration test two-step method to analyze the factors that affect per-capita carbon emissions. The main results are as follows. (1) During 1997, Eastern China, Central China, and Western China ranked first, second, and third in the per-capita carbon emissions, while in 2009 the pecking order changed to Eastern China, Western China, and Central China. (2) According to the LMDI decomposition results, the key driver boosting the per-capita carbon emissions in the three economic regions of China between 1997 and 2009 was economic development, and the energy efficiency was much greater than the energy structure after considering their effect on restraining increased per-capita carbon emissions. (3) Based on the decomposition, the factors that affected per-capita carbon emissions in the panel co-integration test showed that Central China had the best energy structure elasticity in its regional per-capita carbon emissions. Thus, Central China was ranked first for energy efficiency elasticity, while Western China was ranked first for economic development elasticity. PMID:24353753

  13. Factors affecting regional per-capita carbon emissions in China based on an LMDI factor decomposition model.

    PubMed

    Dong, Feng; Long, Ruyin; Chen, Hong; Li, Xiaohui; Yang, Qingliang

    2013-01-01

    China is considered to be the main carbon producer in the world. The per-capita carbon emissions indicator is an important measure of the regional carbon emissions situation. This study used the LMDI factor decomposition model-panel co-integration test two-step method to analyze the factors that affect per-capita carbon emissions. The main results are as follows. (1) During 1997, Eastern China, Central China, and Western China ranked first, second, and third in the per-capita carbon emissions, while in 2009 the pecking order changed to Eastern China, Western China, and Central China. (2) According to the LMDI decomposition results, the key driver boosting the per-capita carbon emissions in the three economic regions of China between 1997 and 2009 was economic development, and the energy efficiency was much greater than the energy structure after considering their effect on restraining increased per-capita carbon emissions. (3) Based on the decomposition, the factors that affected per-capita carbon emissions in the panel co-integration test showed that Central China had the best energy structure elasticity in its regional per-capita carbon emissions. Thus, Central China was ranked first for energy efficiency elasticity, while Western China was ranked first for economic development elasticity.

  14. [Factors affecting infant mortality (author's transl)].

    PubMed

    Chackiel, J

    1982-04-01

    The purpose of this paper is to analyze the differentials and detect factors affecting infant mortality on the basis of data obtained from the fertility surveys from those countries participating in the World Fertility Survey. In particular, this includes the surveys carried out in Colombia, Peru, Costa Rica, Panama, and the Dominican Republic. 3 types of explanatory variables may be considered from the information available: 1) context variables related to the mother's environment; 2) socioeconomic variables based on the educational and economic characteristics of the mother and her last husband; and 3) biological factors (from each woman's pregnancy history) such as mother's age at birth of the child, order of birth, interbirth interval, etc. The countries, whether high or low mortality, present great differences in child mortality in most of the variables considered. In Panama and Costa Rica there are population sectors with infant mortality rates of around 100/1000 live births, whereas in Peru these are over 150/1000 (children from mothers without education, low agricultural strata, etc.). Besides presenting the differentials, a methodological test is made through the application to Costa Rica and Peru of the Proportional Hazards Model which permits analysis of the effects of variables when acting simultaneously upon mortality in early childhood. The variables which show the highest disparity in mortality level are: natural region among the context variables, education of mother among the socioeconomic variables, and interbirth interval and maternal age at birth of their children among the biological ones.

  15. Factors affecting rotator cuff healing after arthroscopic repair: osteoporosis as one of the independent risk factors.

    PubMed

    Chung, Seok Won; Oh, Joo Han; Gong, Hyun Sik; Kim, Joon Yub; Kim, Sae Hoon

    2011-10-01

    The prognostic factors associated with structural outcome after arthroscopic rotator cuff repair have not yet been fully determined. The hypothesis of this study was that bone mineral density (BMD) is an important prognostic factor affecting rotator cuff healing after arthroscopic cuff repair. Cohort study; Level of evidence, 3. Among 408 patients who underwent arthroscopic repair for full-thickness rotator cuff tear between January 2004 and July 2008, 272 patients were included whose postoperative cuff integrity was verified by computed tomography arthrography (CTA) or ultrasonography (USG) and simultaneously who were evaluated by various functional outcome instruments. The mean age at the time of operation was 59.5 ± 7.9 years. Postoperative CTA or USG was performed at a mean 13.0 ± 5.1 months after surgery, and the mean follow-up period was 37.2 ± 10.0 months (range, 24-65 months). The clinical, structural, and surgery-related factors affecting cuff integrity including BMD were analyzed using both univariate and multivariate analysis. Evaluation of postoperative cuff integrity was performed by musculoskeletal radiologists who were unaware of the present study. The failure rate of rotator cuff healing was 22.8% (62 of 272). The failure rate was significantly higher in patients with lower BMD (P < .001); older age (P < .001); female gender (P = .03); larger tear size (P < .001); higher grade of fatty infiltration (FI) of the supraspinatus, infraspinatus, and subscapularis (all P < .001); diabetes mellitus (P = .02); shorter acromiohumeral distance (P < .001); and associated biceps procedure (P < .001). However, in the multivariate analysis, only BMD (P = .001), FI of the infraspinatus (P = .01), and the amount of retraction (P = .03) showed a significant relationship with cuff healing failure following arthroscopic rotator cuff repair. Bone mineral density, as well as FI of the infraspinatus and amount of retraction, was an independent determining factor

  16. Factors that affect the onset of action of non-depolarizing neuromuscular blocking agents

    PubMed Central

    Kim, Yong Byum; Sung, Tae-Yun

    2017-01-01

    Neuromuscular blockade plays an important role in the safe management of patient airways, surgical field improvement, and respiratory care. Rapid-sequence induction of anesthesia is indispensable to emergency surgery and obstetric anesthesia, and its purpose is to obtain a stable airway, adequate depth of anesthesia, and appropriate respiration within a short period of time without causing irritation or damage to the patient. There has been a continued search for new neuromuscular blocking drugs (NMBDs) with a rapid onset of action. Factors that affect the onset time include the potency of the NMBDs, the rate of NMBDs reaching the effect site, the onset time by dose control, metabolism and elimination of NMBDs, buffered diffusion to the effect site, nicotinic acetylcholine receptor subunit affinity, drugs that affect acetylcholine (ACh) production and release at the neuromuscular junction, drugs that inhibit plasma cholinesterase, presynaptic receptors responsible for ACh release at the neuromuscular junction, anesthetics or drugs that affect muscle contractility, site and methods for monitoring neuromuscular function, individual variability, and coexisting disease. NMBDs with rapid onset without major adverse events are expected in the next few years, and the development of lower potency NMBDs will continue. Anesthesiologists should be aware of the use of NMBDs in the management of anesthesia. The choice of NMBD and determination of the appropriate dosage to modulate neuromuscular blockade characteristics such as onset time and duration of neuromuscular blockade should be considered along with factors that affect the effects of the NMBDs. In this review, we discuss the factors that affect the onset time of NMBDs. PMID:29046769

  17. Impact of bracket displacement or rotation during bonding and time of removal of excess adhesive on the bracket-enamel bond strength.

    PubMed

    Oliveira, Adauê S; Barwaldt, Caroline K; Bublitz, Luana S; Moraes, Rafael R

    2014-06-01

    This study investigated the the influence of bracket displacement or rotation during fixation and the time of excess adhesive removal from around the bracket on bond strength to enamel. Stainless steel brackets were bonded to the buccal faces of bovine incisors using Transbond XT® adhesive resin. The teeth were divided into five groups (n = 20). In the control group, no displacement or rotation of the bracket was carried out. In the Displac-A group, excess adhesive was removed after the bracket was displaced 2 mm incisally. In the B-Displac group, excess adhesive was removed before the bracket was displaced incisally. In the Rotat-A group, excess adhesive was removed after the bracket was rotated 45°. In the B-Rotat group, excess adhesive was removed before the bracket was rotated. Photoactivation was carried out on the lateral sides of the bracket. A shear test was conducted 10 min after fixation using a knife-edged chisel. Bond strength data were analysed using ANOVA and Fisher's test (5%). The adhesive remnant index (ARI) was scored under magnification. ARI data were analysed using the Kruskal-Wallis test (5%). No significant differences were detected among the Control, Displac-A, Rotat-A and B-Rotat groups. The B-Displac group showed lower bond strength than all of the other groups, except Displac-A. No significant differences were observed in ARI scores across groups. Displacements of the brackets during fixation did not seem to affect the enamel bond strength when excess adhesive is removed after the final positioning of the bracket. © 2014 British Orthodontic Society.

  18. Effect of 2% chlorhexidine digluconate on bond strength of a glass-fibre post to root dentine.

    PubMed

    Wang, L; Pinto, T A; Silva, L M; Araújo, D F G; Martins, L M; Hannas, A R; Pedreira, A P R V; Francisconi, P A S; Honório, H M

    2013-09-01

    To assess the immediate influence of dentine bonding systems (DBS) associated with 2% chlorhexidine digluconate (CHX) on glass-fibre post-bond strength to root dentine, in terms of coronal, middle and apical thirds. Sixty bovine roots were root filled and randomly assigned to 1 of 6 groups (n = 10): SBMP (3-step etch-and-rinse system, Scotchbond Multi-Purpose), SB (2-step etch-and-rinse system, Single Bond 2), SE (2-step self-etching system, Clearfil SE Bond) and SBMP-CHX, SB-CHX and SE-CHX, respectively, associated with CHX. For all groups, a glass-fibre post was luted with a dual-cure resin cement, RelyX ARC. After 7-day storage, specimens were subjected to the push-out test. Failure modes were analysed under optical microscopy (40x). Bond strength values were statistically analysed by two-way anova and Bonferroni tests (P < 0.05). The effect of DBS was significant (P < 0.05), and SE reached higher bond strength in comparison with the other DBS tested. CHX association did not show improvement with any DBS (P > 0.05); rather, it negatively affected SE, which was detected for all thirds. There was no difference between thirds (P > 0.05), except for the SE-CHX, which presented lower values for the apical third (P < 0.05). Adhesive cement/dentine adhesive failure was predominant for all groups. CHX did not influence the failure mode for any DBS (P > 0.05). The performance of the dentine bonding systems was material dependent. CHX did not improve immediate bond strength; however, CHX negatively affected the bond strength of the self-etching system, especially in the third apical. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  19. Bio-psycho-social factors affecting sexual self-concept: A systematic review

    PubMed Central

    Potki, Robabeh; Ziaei, Tayebe; Faramarzi, Mahbobeh; Moosazadeh, Mahmood; Shahhosseini, Zohreh

    2017-01-01

    Background Nowadays, it is believed that mental and emotional aspects of sexual well-being are the important aspects of sexual health. Sexual self-concept is a major component of sexual health and the core of sexuality. It is defined as the cognitive perspective concerning the sexual aspects of ‘self’ and refers to the individual’s self-perception as a sexual creature. Objective The aim of this study was to assess the different factors affecting sexual self-concept. Methods English electronic databases including PubMed, Scopus, Web of Science and Google Scholar as well as two Iranian databases including Scientific Information Database and Iranmedex were searched for English and Persian-language articles published between 1996 and 2016. Of 281 retrieved articles, 37 articles were finally included for writing this review article. Results Factors affecting sexual self-concept were categorized to biological, psychological and social factors. In the category of biological factors, age gender, marital status, race, disability and sexual transmitted infections are described. In the psychological category, the impact of body image, sexual abuse in childhood and mental health history are present. Lastly, in the social category, the roles of parents, peers and the media are discussed. Conclusion As the development of sexual self-concept is influenced by multiple events in individuals’ lives, to promotion of sexual self-concept, an integrated implementation of health policies is recommended. PMID:29038693

  20. Bio-psycho-social factors affecting sexual self-concept: A systematic review.

    PubMed

    Potki, Robabeh; Ziaei, Tayebe; Faramarzi, Mahbobeh; Moosazadeh, Mahmood; Shahhosseini, Zohreh

    2017-09-01

    Nowadays, it is believed that mental and emotional aspects of sexual well-being are the important aspects of sexual health. Sexual self-concept is a major component of sexual health and the core of sexuality. It is defined as the cognitive perspective concerning the sexual aspects of 'self' and refers to the individual's self-perception as a sexual creature. The aim of this study was to assess the different factors affecting sexual self-concept. English electronic databases including PubMed, Scopus, Web of Science and Google Scholar as well as two Iranian databases including Scientific Information Database and Iranmedex were searched for English and Persian-language articles published between 1996 and 2016. Of 281 retrieved articles, 37 articles were finally included for writing this review article. Factors affecting sexual self-concept were categorized to biological, psychological and social factors. In the category of biological factors, age gender, marital status, race, disability and sexual transmitted infections are described. In the psychological category, the impact of body image, sexual abuse in childhood and mental health history are present. Lastly, in the social category, the roles of parents, peers and the media are discussed. As the development of sexual self-concept is influenced by multiple events in individuals' lives, to promotion of sexual self-concept, an integrated implementation of health policies is recommended.