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91.
Teixeira EC Piascik JR Stoner BR Thompson JY 《Journal of materials science. Materials in medicine》2007,18(6):1219-1224
Fracture strength and fatigue parameters of three ceramic materials submitted to dynamic fatigue were evaluated. A machinable
leucite-reinforced dental ceramic, aluminum oxide, and yttria-stabilized zirconia (YSZ) were tested. The inert strength of
the materials was determined in air (25 °C) at stressing rates of 70, 250, 400 MPa/s for Porcelain, Alumina and YSZ respectively.
The data was analyzed using a two-parameter Weibull distribution. The Weibull modulus (m) and the characteristic of fracture (σ
0) parameters were determined for each material. Specimens were also tested in 3-point bending at different stressing rates
in distilled/deionized water at 37 °C (dynamic fatigue) in order to calculate the fatigue parameters n and ln B. The strength for each material was characterized using Strength–Probability–Time (SPT) diagrams for 1 day, 1 year and 10 years.
YSZ showed a high-fracture strength σ
0 (1,459 MPa) at a failure probability of 63.2% and high resistance to subcritical crack growth. YSZ and alumina showed better
resistance to slow crack growth than porcelain, indicating less susceptibility to strength degradation by stress corrosion.
Lifetime predictions after 10 years indicate a reduction of 50%, 36% and 29% in strength for porcelain, alumina and YSZ respectively.
YSZ seems to be a very promising material for long-term dental and biomedical applications. 相似文献
92.
Rufus Vinod Randa Mahran Erica Routila Janne Leivo Kim Pettersson Kamlesh Gidwani 《International journal of molecular sciences》2021,22(19)
Extracellular vesicles (EVs) are found in all biological fluids, providing potential for the identification of disease biomarkers such as colorectal cancer (CRC). EVs are heavily glycosylated with specific glycoconjugates such as tetraspanins, integrins, and mucins, reflecting the characteristics of the original cell offering valuable targets for detection of CRC. We report here on europium-nanoparticle (EuNP)-based assay to detect and characterize different surface glycoconjugates of EVs without extensive purification steps from five different CRC and the HEK 293 cell lines. The promising EVs candidates from cell culture were clinically evaluated on small panel of serum samples including early-stage (n = 11) and late-stage (n = 11) CRC patients, benign condition (n = 11), and healthy control (n = 10). The majority of CRC cell lines expressed tetraspanin sub-population and glycovariants of integrins and conventional tumor markers. The subpopulation of CD151 having CD63 expression (CD151CD63) was significantly (p = 0.001) elevated in early-stage CRC (8 out of 11) without detecting any benign and late-stage samples, while conventional CEA detected mostly late-stage CRC (p = 0.045) and with only four early-stage cases. The other glycovariant assays such as CEACon-A, CA125WGA, CA 19.9Ma696, and CA 19.9Con-A further provided some complementation to the CD151CD63 assay. These results indicate the potential application of CD151CD63 assay for early detection of CRC patients in human serum. 相似文献
93.
Francesco Dituri Serena Mancarella Grazia Serino Nada Chaoul Luigi Giovanni Lupo Erica Villa Isabel Fabregat Gianluigi Giannelli 《International journal of molecular sciences》2021,22(21)
The balance between anti-tumor and tumor-promoting immune cells, such as CD4+ Th1 and regulatory T cells (Tregs), respectively, is assumed to dictate the progression of hepatocellular carcinoma (HCC). The transforming growth factor beta (TGFβ) markedly shapes the HCC microenvironment, regulating the activation state of multiple leukocyte subsets and driving the differentiation of cancer associated fibroblasts (CAFs). The fibrotic (desmoplastic) reaction in HCC tissue strongly depends on CAFs activity. In this study, we attempted to assess the role of TGFβ on transendothelial migration of Th1-oriented and Treg-oriented CD4+ T cells via a direct or indirect, CAF-mediated mechanisms, respectively. We found that the blockage of TGFβ receptor I-dependent signaling in Tregs resulted in impaired transendothelial migration (TEM) of these cells. Interestingly, the secretome of TGFβ-treated CAFs inhibited the TEM of Tregs but not Th1 cells, in comparison to the secretome of untreated CAFs. In addition, we found a significant inverse correlation between alpha-SMA and FoxP3 (marker of Tregs) mRNA expression in a microarray analysis involving 78 HCCs, thus suggesting that TGFβ-activated stromal cells may counteract the trafficking of Tregs into the tumor. The apparent dual behavior of TGFβ as both pro- and anti-tumorigenic cytokines may add a further level of complexity to the mechanisms that regulate the interactions among cancerous, stromal, and immune cells within HCC, as well as other solid tumors, and contribute to better manipulation of the TGFβ signaling as a therapeutic target in HCC patients. 相似文献
94.
Forzani ES Li X Zhang P Tao N Zhang R Amlani I Tsui R Nagahara LA 《Small (Weinheim an der Bergstrasse, Germany)》2006,2(11):1283-1291
A method to functionalize single-walled carbon nanotubes (SWNTs) in a field-effect transistor (FET) device for the selective detection of heavy-metal ions is presented. In this method, peptide-modified polymers were electrochemically deposited onto SWNTs and the selective detection of metal ions was demonstrated by choosing appropriate peptide sequences. The signal transduction mechanism of the peptide-modified SWNT-FETs has also been studied. 相似文献
95.
This study presents a new approach for improving the structure, and hence the robustness, of the SPME fiber coating applied for gas chromatography (GC) analysis. It involves application of an external layer of poly(dimethyl siloxane) (PDMS) over the commercial PDMS/divinyl benzene (DVB) extraction phase. The fiber provided extraction capabilities similar to that exhibited by the original PDMS/DVB fiber toward triazole pesticides from water samples. Furthermore, the fiber could be utilized for over 100 extractions in direct contact with a complex food matrix such as whole grape pulp, with no sample pretreatment required. The amount of extracted pesticides from whole grape pulp had RSD values below 20% throughout 130 extraction/desorption/conditioning cycles, which is a dramatic improvement when compared to commercial PDMS/DVB fiber coating applied in food analysis facilitating high-throughput automation. 相似文献
96.
A nitrogen oxide (NO(x); x = 1, 2) optical sensor with an extremely low detection limit in the range of fractions of ppbV (0.3 ppbV for 20 s sample injection) is presented. Phenylenediamine derivatives are utilized as molecular probes in the solid state on a nanoporous membrane to produce a miniaturized and low cost sensing platform for use as a wearable personal monitor. 相似文献
97.
Making sense of family conflict: Intimate partner violence and preschoolers’ externalizing problems.
Minze Laura C.; McDonald Renee; Rosentraub Erica L.; Jouriles Ernest N. 《Canadian Metallurgical Quarterly》2010,24(1):5
This research examines relations among parental intimate partner violence (IPV), preschoolers’ narrative coherence about family conflict situations, and preschoolers’ externalizing problems. Participants were 57 mothers and their 4- to 5-year-old children. Mothers provided data on IPV and children’s externalizing problems. Narrative coherence was coded from children’s play narratives in response to story stems from the MacArthur Story Stem Battery. Results are consistent with theory suggesting that exposure to IPV may adversely affect preschoolers’ ability to understand family conflict situations in an organized manner, which in turn may contribute to their externalizing problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Markman Howard J.; Rhoades Galena K.; Stanley Scott M.; Ragan Erica P.; Whitton Sarah W. 《Canadian Metallurgical Quarterly》2010,24(3):289
Using data from 210 couples who provided data across the first 5 years of marriage, we examined how premarital communication quality was related to divorce and later distress. The results showed that premarital observed negative and positive communication nearly reached significance as predictors of divorce, while self-reported negative communication was significantly associated with divorce. In terms of marital adjustment, we found that both premarital observed and self-reported negative premarital communication (but not observed positive communication) were associated with lower adjustment during the first 5 years of marriage. The most important questions addressed in this study pertain to how positive and negative dimensions of communication change over time and how these changes are related to being distressed or nondistressed after 5 years of marriage. This is the first study, to our knowledge, to examine the changes in communication over time that are so central to theories of the development of marital distress and for research-based interventions. We found that all couples showed decreases in negative communication over time, but the nondistressed group declined significantly more than the distressed group in negative communication, suggesting they are handling negative emotions better. Implications for future research on the development of relationship distress and for enhancing research-based couples' intervention programs are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Wise Erica H.; Sturm Cynthia A.; Nutt Roberta L.; Rodolfa Emil; Schaffer Jack B.; Webb Carol 《Canadian Metallurgical Quarterly》2010,41(4):288
As a profession we are committed to maintaining and enhancing our competence as psychologists in order to most effectively serve the public throughout our careers. While this is a widely shared commitment among psychologists, there is considerably less consensus regarding how best to accomplish this goal. This dilemma is examined from the ethical, educational and legal perspectives. The American Psychological Association (APA) Ethics Code clearly articulates that competence is an ethical duty, although there is little guidance provided in the code as to how to meet this standard. As a profession we have tended to focus on the construct of life-long learning and we have incorporated this principle into our education and training standards. In fact, APA accreditation requires that doctoral programs inculcate this value into our foundational training. The majority of Psychology Licensing Boards have addressed this issue through the endorsement of mandatory continuing education requirements that primarily focus on hours and the content or structure of approved programs. Potential limitations to our ability to effectively self-assess our professional training needs are discussed and several innovative models are presented for integrating effective self-assessment and continuing education. Three invited experts provide commentaries that further explore the challenges and dilemmas posed by the ethical, legal and professional duty to maintain and enhance competence throughout our professional careers. These commentaries broaden the considerations, provide practical suggestions from other professions and provide a vision for the future. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Limin Kung Megan L. Smith Erica Benjamim da Silva Michelle C. Windle Thiago C. da Silva Stephanie A. Polukis 《Journal of dairy science》2018,101(7):5949-5960
We evaluated the effectiveness of an additive comprising sodium benzoate, potassium sorbate, and sodium nitrite (SSL) as active ingredients for its ability to improve the aerobic stability of corn silages made in North America. In experiment 1, treatment with SSL (1.5 and 2.0 L/t) on whole-plant corn (WPC) was compared with treatment with an additive containing buffered propionic acid and citric acid (BPA; 2 L/t) on corn harvested at 32 and 38% dry matter and ensiled for 120 d. Silage treated with BPA was higher in ammonia-N and propionic acid relative to other treatments. Treatments with all of the additives had numerically, but not statistically, fewer yeasts compared with untreated silage. Both application rates of SSL resulted in lower concentrations of ethanol compared with untreated and BPA silages. Treatment with BPA improved the aerobic stability of silages compared with untreated silage, but the effect from SSL was markedly greater. In experiment 2, WPC was untreated or treated with 2 or 3 L of SSL/t or a microbial inoculant containing Enterococcus faecium M74, Lactobacillus plantarum CH6072, and Lactobacillus buchneri LN1819 (final total lactic acid bacteria application rate of 150,000 cfu/g of fresh forage). Silages were air stressed for 24 h at 28 and 42 d of storage and ensiled for 49 d before opening. Inoculation had no effect on acid end products, ethanol, number of yeasts, or aerobic stability compared with other treatments. Treatment with SSL decreased the amount of ethanol, had no effect on number of yeasts, and improved aerobic stability in a dose-dependent manner compared with other treatments. In experiment 3, WPC was untreated or treated with 2 L of SSL/t and ensiled for 5, 15, and 30 d. Treatment with SSL resulted in silage with fewer yeasts and lower concentrations of ethanol after all times of ensiling compared with untreated silage. In addition, SSL improved aerobic stability after each period of ensiling, but the effect was more at 15 and 30 d compared with 5 d of storage. Treating WPC with SSL can improve the aerobic stability of corn silage made in North America, and the effect can be observed as soon as 5 d after ensiling. 相似文献