Application of Neural Networks for Estimation of Concrete Strength

The uniaxial compressive strength of concrete is the most widely used criterion in producing concrete. Although testing of the uniaxial compressive strength of concrete specimens is done routinely, it is performed on the 28th day after concrete placement. At this point, it is too late to make improvements if the test result does not satisfy the required strength. Therefore, the strength estimation before the placement of concrete is highly desirable. This study presents the first effort in applying neural network-based system identification techniques to predict the compressive strength of concrete based on concrete mix proportions. Back-propagation neural networks were developed, trained, and tested using actual data sets of concrete mix proportions provided by two ready-mixed concrete companies. The compressive strengths estimated by the neural networks were verified by laboratory testing results. This study demonstrated that the neural network techniques are effective in estimating the compressive strength of concrete based on the mix proportions. Application of these techniques will contribute significantly to the concrete quality assurance

Analysis of Mechanical Strain in AlGaN/GaN HFETs

Herein, the influence of mechanical strain induced by passivation layers on the electrical performance of AlGaN/GaN heterostructure field-effect transistor is investigated. We studied the physical mechanism of a threshold voltage (Vth) shift for the monolithically fabricated on/off devices reported earlier by our group. For that, theoretical calculations, simulation-based analysis, and nano-beam electron diffraction (NBED) measurements based on STEM are used. Strain distribution in the gate vicinity of transistors is compared for a SiNx passivation layer with intrinsic stress from ≈0.5 to −1 GPa for normally on and normally off devices, respectively. The strain in epitaxial layers transferred by intrinsic stress of SiNx is quantitatively evaluated using NEBD method. Strain dissimilarity Δε = 0.23% is detected between normally on and normally off devices. Using this method, quantitative correlation between 1.13 V of Vth shift and microscopic strain difference in the epitaxial layers caused by 1.5 GPa intrinsic stress variation in passivation layer is provided. It is showed in this correlation that about half of the reported threshold voltage shift is induced by strain, i.e., by the piezoelectric effect. The rest of Vth shift is caused by the fabrication process. Therefore, various components/mechanisms contributing to the measured Vth shift are distinguished

The Pathology of Neoatherosclerosis in Human Coronary Implants Bare-Metal and Drug-Eluting Stents

ObjectivesHuman coronary bare-metal stents (BMS) and drug-eluting stents (DES) from autopsy cases with implant duration >30 days were examined for the presence of neointimal atherosclerotic disease.BackgroundNeointimal atherosclerotic change (neoatherosclerosis) after BMS implantation is rarely reported and usually occurs beyond 5 years. The incidence of neoatherosclerosis after DES implantation has not been reported.MethodsAll available cases from the CVPath stent registry (n = 299 autopsies), which includes a total of 406 lesions—197 BMS, 209 DES (103 sirolimus-eluting stents [SES] and 106 paclitaxel-eluting stents [PES])—with implant duration >30 days were examined. Neoatherosclerosis was recognized as clusters of lipid-laden foamy macrophages within the neointima with or without necrotic core formation.ResultsThe incidence of neoatherosclerosis was significantly greater in DES lesions (31%) than BMS lesions (16%; p < 0.001). The median stent duration with neoatherosclerosis was shorter in DES than BMS (DES, 420 days [interquartile range [IQR]: 361 to 683 days]; BMS, 2,160 days [IQR: 1,800 to 2,880 days], p < 0.001). Unstable lesions characterized as thin-cap fibroatheromas or plaque rupture were more frequent in BMS (n = 7, 4%) than in DES (n = 3, 1%; p = 0.17), with relatively shorter implant durations for DES (1.5 ± 0.4 years) compared to BMS (6.1 ± 1.5 years). Independent determinants of neoatherosclerosis identified by multiple logistic regression included younger age (p < 0.001), longer implant durations (p < 0.001), SES usage (p < 0.001), PES usage (p = 0.001), and underlying unstable plaques (p = 0.004).ConclusionsNeoatherosclerosis is a frequent finding in DES and occurs earlier than in BMS. Unstable features of neoatherosclerosis are identified for both BMS and DES with shorter implant durations for the latter. The development of neoatherosclerosis may be yet another rare contributing factor to late thrombotic events

Acute Thrombogenicity of a Durable Polymer Everolimus-Eluting Stent Relative to Contemporary Drug-Eluting Stents With Biodegradable Polymer Coatings Assessed Ex Vivo in a Swine Shunt Model

AbstractObjectivesThis study sought to evaluate whether the permanent fluoropolymer-coated Xience Xpedition everolimus-eluting stent (Xience-EES) exhibits lower acute thrombogenicity compared with contemporary drug-eluting stents (DES) with biodegradable polymer coatings in an acute swine shunt model.BackgroundPrevious pre-clinical and clinical experience suggests that several factors may influence the predisposition for acute thrombus formation of polymer-coated DES, including stent design and the polymer coating technology. It remains unclear whether relevant differences exist with respect to acute thrombogenicity, particularly between current commercial stent designs using permanent polymers and those using biodegradable polymers.MethodsAn ex vivo carotid to jugular arteriovenous porcine shunt model involving a test circuit of 3 in-line stents, was used to test acute thrombogenicity, where Xience-EES (n = 24) was compared with 4 CE-marked DES with biodegradable polymer coatings (BioMatrix Flex, Synergy, Nobori, and Orsiro [n = 6 each]). After 1 h of circulation, platelet aggregation in whole mount stents was evaluated by confocal microscopy with immunofluorescent staining against dual platelet markers (CD61/CD42b) along with scanning electron microscopy.ResultsXience-EES showed the least percentage of thrombus-occupied area as compared with the biodegradable polymer-coated DES, with a significant difference compared with BioMatrix Flex and Synergy (mean differences: [BioMatrix Flex: 15.54, 95% confidence interval [CI]: 11.34 to 19.75, p < 0.001; Synergy: 8.64, 95% CI: 4.43 to 12.84, p < 0.001; Nobori: 4.22, 95% CI: -0.06 to 8.49, p = 0.055; Orsiro: 2.95, 95% CI: -1.26 to 7.15, p = 0.286). The number of cell nuclei on strut surfaces was also the least in Xience-EES, with a significant difference relative to BioMatrix Flex, Nobori, and Orsiro (mean ratios: BioMatrix Flex: 4.73, 95% CI: 2.46 to 9.08, p < 0.001; Synergy: 1.44, 95% CI: 0.75 to 2.76, p = 0.51; Nobori: 5.97, 95% CI: 3.11 to 11.44, p < 0.001; Orsiro: 5.16, 95% CI: 2.69 to 9.91, p < 0.001).ConclusionsXience-EES’s overall design confers acute thromboresistance relative to contemporary DES with biodegradable coatings, with less platelet aggregation versus BioMatrix Flex and Synergy, and less inflammatory cell attachment versus BioMatrix Flex, Nobori, and Orsiro, in an ex vivo swine shunt model, which lends support to reported clinical findings of lower early stent thrombosis

Three novel mutations in KIF21A highlight the importance of the third coiled-coil stalk domain in the etiology of CFEOM1

<p>Abstract</p> <p>Background</p> <p>Congenital fibrosis of the extraocular muscles types 1 and 3 (CFEOM1/CFEOM3) are autosomal dominant strabismus disorders that appear to result from maldevelopment of ocular nuclei and nerves. We previously reported that most individuals with CFEOM1 and rare individuals with CFEOM3 harbor heterozygous mutations in <it>KIF21A</it>. <it>KIF21A </it>encodes a kinesin motor involved in anterograde axonal transport, and the familial and <it>de novo </it>mutations reported to date predictably alter one of only a few KIF21A amino acids – three within the third coiled-coil region of the stalk and one in the distal motor domain, suggesting they result in altered KIF21A function. To further define the spectrum of <it>KIF21A </it>mutations in CFEOM we have now identified all CFEOM probands newly enrolled in our study and determined if they harbor mutations in <it>KIF21A</it>.</p> <p>Results</p> <p>Sixteen CFEOM1 and 29 CFEOM3 probands were studied. Three previously unreported <it>de novo </it>KIF21A mutations were identified in three CFEOM1 probands, all located in the same coiled-coil region of the stalk that contains all but one of the previously reported mutations. Eight additional CFEOM1 probands harbored three of the mutations previously reported in <it>KIF21A</it>; seven had one of the two most common mutations, while one harbored the mutation in the distal motor domain. No mutation was detected in 5 CFEOM1 or any CFEOM3 probands.</p> <p>Conclusion</p> <p>Analysis of sixteen CFEOM1 probands revealed three novel <it>KIF21A </it>mutations and confirmed three reported mutations, bringing the total number of reported <it>KIF21A </it>mutations in CFEOM1 to 11 mutations among 70 mutation positive probands. All three new mutations alter amino acids in heptad repeats within the third coiled-coil region of the KIF21A stalk, further highlighting the importance of alterations in this domain in the etiology of CFEOM1.</p

Immune response of macrophages from young and aged mice to the oral pathogenic bacterium Porphyromonas gingivalis

Periodontal disease is a chronic inflammatory gum disease that in severe cases leads to tooth loss. Porphyromonas gingivalis (Pg) is a bacterium closely associated with generalized forms of periodontal disease. Clinical onset of generalized periodontal disease commonly presents in individuals over the age of 40. Little is known regarding the effect of aging on inflammation associated with periodontal disease. In the present study we examined the immune response of bone marrow derived macrophages (BMM) from young (2-months) and aged (1-year and 2-years) mice to Pg strain 381. Pg induced robust expression of cytokines; tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10, chemokines; neutrophil chemoattractant protein (KC), macrophage colony stimulating factor (MCP)-1, macrophage inflammatory protein (MIP)-1α and regulated upon activation normal T cell expressed and secreted (RANTES), as well as nitric oxide (NO, measured as nitrite), and prostaglandin E2 (PGE2) from BMM of young mice. BMM from the 2-year age group produced significantly less TNF-α, IL-6 and NO in response to Pg as compared with BMM from 2-months and 1-year of age. We did not observe any difference in the levels of IL-1β, IL-10 and PGE2 produced by BMM in response to Pg. BMM from 2-months and 1-year of age produced similar levels of all chemokines measured with the exception of MCP-1, which was reduced in BMM from 1-year of age. BMM from the 2-year group produced significantly less MCP-1 and MIP-1α compared with 2-months and 1-year age groups. No difference in RANTES production was observed between age groups. Employing a Pg attenuated mutant, deficient in major fimbriae (Pg DPG3), we observed reduced ability of the mutant to stimulate inflammatory mediator expression from BMMs as compared to Pg 381, irrespective of age. Taken together these results support senescence as an important facet of the reduced immunological response observed by BMM of aged host to the periodontal pathogen Pg

Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p&lt;0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (&lt;1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (&lt;1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline