scholarly journals Retentive Characteristics of a Polyetheretherketone Post-Core Restoration with Polyvinylsiloxane Attachments

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2005
Author(s):  
Ping Li ◽  
Dorina Hasselbeck ◽  
Alexey Unkovskiy ◽  
Feraydoon Sharghi ◽  
Sebastian Spintzyk

A new application of a polyetheretherketone (PEEK) post-core restoration combined with polyvinylsiloxane (PVS) attachments was proposed and substantiated. This study aimed to evaluate retentive characteristics of the PEEK post-core restoration with PVS attachment systems. Specimens with PVS attachments were fabricated to evaluate retention force during 10,000 cyclic dislodgements. Additionally, the retention forces of PVS attachments with three different values of Shore hardness were further measured before and after aging treatments. The results of cyclic dislodgement test indicated a strong negative linear relationship between the cyclic times and retention force (p < 0.0001, r = −0.957). Furthermore, the retention forces of the PVS were significantly improved with Shore hardness increased, which was also affected by the aging treatment (F (2, 138) = 10.95, p < 0.0001). Therefore, the PEEK post-core restoration with PVS attachments exhibited the favorable retention force, which could be a promising alternative for dental prostheses.

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 510f-511 ◽  
Author(s):  
D.C. Ferree ◽  
S.J. McArtney ◽  
D.M. Scurlock

Four French–American hybrid grape cultivars grown in a greenhouse were subjected to 5 days of 80% shade at four different times around bloom. Fruit set of `Seyval' was reduced by shade imposed before, during, or immediately after bloom. `Vidal' and `Chambourcin' were less sensitive, with fruit set reduced only by shade at bloom. Shade had little effect on fruit set of `DeChaunac'. In a second study, `Chambourcin' vines were exposed to ambient, ambient plus supplemental lights, and 30%, 50%, or 80% shade for 5 weeks beginning just prior to bloom. Fruit set was positively related to light intensity. At harvest, soluble solids, pH, and hue angle had a negative linear relationship to light level. Fruit color developed earliest and most rapidly with the reduced light treatments applied at bloom. Cluster weight was positively related to light intensity.


2019 ◽  
Author(s):  
Xiaoyan Jia ◽  
Ping Chen ◽  
Xue Wang ◽  
Xianglei Kong ◽  
Juan Chen ◽  
...  

Abstract Background: Few studies are available on the non-linear association between serum albumin (S-Alb) level and prognosis in maintenance hemodialysis (MHD) patients. Methods: All stable MHD patients treated in our center from 2007 to 2011 were enrolled into this study. Demographics, laboratory data, hospitalization and mortality were collected; Cox regressive models were fitted to investigate predicting outcomes, restricted cubic splines (RCS) were allowing for non-linear association between S-Alb and prognosis. Results: S-Alb was independent protective factor for mortality, all-cause hospitalization, hospitalization for cardiovascular or cerebrovascular disease and hospitalization for infection. The relationships between S-Alb and mortality, all-cause hospitalization, hospitalization for cardiovascular or cerebrovascular disease were U-shaped; relationships between S-Alb and hospitalization for infection were negative linear relationships both in univariable Cox regression models and in multivariable Cox regression. Conclusions: In MHD population, there were “U-shaped” relationships between serum albumin level and mortality or hospitalization; the potential risks associated with excessive S-Alb should been taken into consideration. There was negative linear relationship between S-Alb and hospitalization for infection, S-Alb may be even more important in preventing infection in MHD population.


2020 ◽  
Vol 93 (6) ◽  
pp. 2163-2175
Author(s):  
Yichen Wang ◽  
Renzhan Yin ◽  
Meiyun Chai ◽  
Nishu ◽  
Chong Li ◽  
...  

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Xiangfei Cui ◽  
Guoming Liu ◽  
Cheng-long Wang ◽  
Yudong Qi

Polyethylene terephthalate (PET) fiber from waste plastic bottles is an environmentally friendly fiber that can improve the mechanical properties of wet-mix shotcrete. The main objective of this paper is to investigate the effects of PET fiber parameters on pumpability, shootability, and mechanical properties of wet-mix shotcrete. For this purpose, the orthogonal test based on three factors and three levels was conducted. The width, length, and content of PET fiber were selected as the experimental variables. The tests of wet-mix shotcrete reinforced by PET fibers were carried out, along with properties tests such as slump, pressure drop, build-up thickness, compressive strength, and splitting strength. The results showed the change trend of shotcrete performances with increasing PET fiber parameters (width, length, and content). According to the orthogonal test, PET fiber parameters were determined (1 mm width, 20 mm length, and 5 kg/m3 content). Furthermore, relationships between slump and pumpability and shootability were explored, as well as the relationships between pumpability, shootability, and mechanical properties. It was found that pressure drop and compressive strength had the strongest negative linear relationship among all fitting relationships. We hoped that this study could contribute the useful information for the application of wet-mix shotcrete mixed with PET fibers.


2019 ◽  
Vol 9 (23) ◽  
pp. 5077
Author(s):  
Aleksandra Sender-Janeczek ◽  
Jacek Zborowski ◽  
Małgorzata Szulc ◽  
Tomasz Konopka

Combination of the classical subgingival instrumentation (scaling and root planing procedure, SRP) with an antibiotic administered to periodontal pockets in a suitable medium is a promising alternative protocol of nonsurgical periodontal treatment. It enables obtaining the long-term minimum drug concentration inhibiting the development of periopathogens. Objectives: Clinical and microbiological evaluation of periodontal pockets two months after single application of a gel containing piperacillin and tazobactam (Gelcide)® in relation to the nonsurgical treatment procedure (SRP). Materials and methods: Ten patients aged 24–56 years (mean 39.5) with chronic periodontitis, nonsmokers with acceptable oral hygiene and no classical exclusion criteria were qualified for treatment. In the maxilla area, SRP was performed and the assessed gel was inserted to two randomly selected adjacent periodontal pockets. Clinical evaluation included the assessment of bleeding on probing (BoP), pocket depth (PD), and clinical attachment loss (CAL) at six measurement points. A microbiological examination with the use of PET deluxe diagnostic kit in the drug-administered pockets and symmetrically in two pockets on the other side of the dental arch was performed. The examination was conducted before the treatment and two months later. Results: Two months after the treatment, a significant improvement in all analyzed clinical parameters was observed. However, the extent of this improvement did not differ significantly between the compared treatment methods. No statistically significant differences were found in the number of bacteria before and after the treatment, except for a significant decrease in the number of Micromonas micros (2957 vs. 589, p = 0.028) and a higher number of the green complex bacteria Capnocytophaga gingivalis (5439 vs. 2050, p = 0.041) after antibiotic had been used. Conclusion: No significant clinical and microbiological differences were found after additional administration of gel with piperacillin and tazobactam in relation to SRP in the preliminary study.


Author(s):  
Lorenz S. Neuwirth

Cellular phone distractions inhibit faculty delivering and students learning the curriculum by reducing student attendance and active engagement. Arguably, cellular phone usage during precious class times can be a risk factor for student attrition, but scarce solutions have been offered to address this problem in colleges. The Flipd App, a cellular phone distraction reduction technology was tested on 266 college students. The results showed a positive linear relationship between usage and attendance rates and a negative linear relationship between usage and ≥ 3 absence rates, and ∼10% of students resisted its use. The Flipd App may serve as a predictive educational intervention tool that increases active learning, reduces attrition, and increases retention. It may be useful in classes with less hands-on activities to reduce distractions and increase active student engagement. The Flipd App may prove useful in helping college students curb their screen time habits from the Fear of Missing Out to the Joy of Missing Out.


1989 ◽  
Vol 16 (2) ◽  
pp. 76-82
Author(s):  
Gregory B. Parker ◽  
Olin D. Smith ◽  
W. James Grichar

Abstract Colorimetry was evaluated as a method to assess pod disease in peanuts (Arachis hypogaea L.) caused primarily by Pythium myriotylum Drechs., Sclerotium rolfsii Sacc., and Rhizoctonia solani Kuhn. Data analyzed were from nineteen replicated tests conducted from 1982 to 1987, exclusive of 1985, in three South Texas locations. Each plot was scored for pod disease colorimetrically and visually. A negative linear relationship (R2&gt;96%) was found between Hunter color values (L and b) and percent infection measured visually for samples hand selected to approximate eleven disease levels varying from 0-100%. Variability among readings was less at extremes of infection. Correlation both between visual ratings and between visual and colorimetric ratings was affected by soil differences, pathogens infecting the pods, pod genotype, and level of infection present. Correlation among visual raters was generally higher than that between color value ratings. Two-thirds of the lines in these tests classified visually as being in the best 50% for pod disease were also in the best 50% according to colorimetric scores. Use of colorimetry in conjunction with a single visual rating was estimated to increase efficiency and reduce costs of evaluation compared to multiple visual ratings.


2005 ◽  
Vol 475-479 ◽  
pp. 1503-1506 ◽  
Author(s):  
Koichi Matsuda ◽  
Yoshimi Watanabe ◽  
Kazuhisa Yamagiwa ◽  
Yasuyoshi Fukui

Near net shape forming of Al-Al3Fe functionally graded materials (FGMs) have been studied. FGM billets fabricated by a centrifugal method were extruded under the condition of a mixture of molten Al eutectic and solid Al3Fe particles. Both distribution and profile of Al3Fe particles were characterized by and the variation of volume fraction of Al3Fe particles was observed. Shore hardness of the Al matrix was also measured to evaluate the strength of the FGM before and after the semi-solid forming associated with the character of distributed Al3Fe particles. It was confirmed that Shore hardness increased with increasing the volume fraction of Al3Fe particles and after the semi-solid forming than before. This was due to the fact that Al3Fe particles after the semi-solid forming became fine by shear stress introduced by liquid Al flow.


2000 ◽  
Vol 125 (5) ◽  
pp. 553-557 ◽  
Author(s):  
B.R. Bondada ◽  
C.E. Sams ◽  
D.E. Deyton ◽  
J.C. Cummins

Environmental factors such as rainfall may reduce the efficacy of foliar-applied soybean [Glycine max (L.) Merrill] oil in reducing pest mortality. Greenhouse studies were conducted to investigate the influence of rain on the retention of soybean oil and the influence of soybean oil and rainfall on surface morphology of apple [Malus sylvestris (L.) Mill var. domestica (Borkh.) Mansf.] and peach [Prunus persica (L.) Batsch (Peach Group)] leaves and stems. `Contender' peach and `Golden Delicious'/Malling 27 apple trees were grown in 19 L pots in a greenhouse (23 ± 9 °C) and sprayed with soybean oil (1%) emulsified with the adjuvants Latron B-1956 or K1. Twenty-four hours after treatment, the trees were subjected to simulated rainfall of 0.0, 0.25, 1.25, or 2.54 cm. A negative linear relationship existed between rainfall and oil retention. Peach leaves receiving 0.25, 1.25, and 2.54 cm rainfall retained 81%, 38%, and 18% of the applied oil, respectively. Oil retention by apple leaves was also negatively related to rainfall. For both species, a negative linear relationship existed between oil retention on stems and rainfall. There was no effect of emulsifier on retention of 1% soybean oil after rain on apple leaves or on the retention of 8% to 11% soybean oil on the stems of apple and peach. Scanning electron microscopy revealed that epicuticular wax occurred as striations on apple and peach leaves. The wax morphology on peach and apple stems appeared as thin plates and platelets, respectively. The wax morphology of leaves and stems of both trees was not affected either by the soybean oil emulsions or rain. Both emulsions induced stomatal closure in leaves and peach stems, however, stomates opened after rainfall of 1.25 or 2.54 cm. The lenticels appeared to be unaffected by either emulsion. Results illustrate that rainfall of 2.54 cm washed off a major portion of the applied oil. Thus, respraying may be needed under natural climatic conditions with rainfall ≥2.54 cm to restore the efficacy of applied soybean oil.


2018 ◽  
Vol 930 ◽  
pp. 43-47
Author(s):  
Cristiane Fonseca de Carvalho ◽  
Cláudio Luis de Melo-Silva ◽  
Tereza Cristina Favieri de Melo-Silva ◽  
Fábio Amaral de Araújo ◽  
Jefferson Fabricio Cardoso Lins

The aim of this study was to analyze the flexural strength of ceramics based on yttria-stabilized zirconia (YTZP) , used in the manufacture of dental prostheses infrastructure before and after aging with cyclic fatigue in moisture. The samples were made by pre-sintered blocks of ZirkonTransluzent (Zirkonzahn GMHB) from YTZP ceramics with and without feldspathic ceramic coating, divided into groups: G1 = YTZP control; G2 = YTZP aged; G3 = YTZP + feldspathic; G4 = YTZP + aged feldspathic. The samples were submitted to a three-point bending test with a speed of 0.5 mm / min. The mean values of the flexural strength values were G1 = 645 MPa (DP ± 124), G2 = 681 MPa (DP ± 129), G3 = 904Mpa (DP ± 157) and G4 = 954Mpa (DP ± 243). The values of groups G1 and G2; G3 and G4 were statistically similar, depending on the presence or absence of coating. Cyclic stresses did not affect the flexural strength of the material


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