476 research outputs found

    Aging and Degradation Behavior Elucidated by Viscoelasticity Aiming Protection of Smart City Facilities

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    Polymer coatings play a crucially important role in protecting smart city facilities against the harsh factors of outdoor environments. Recent increased awareness of ecoā€friendliness has led to the use of waterborne organic coatings. Research into the bulk material properties of these coatings is necessary in order to understand their degradation process in the field. The present work focuses attention on a unique rheological property, which has both elastic and viscous characteristics, as a means of assessing the stability of the coating. The viscoelastic property determines whether it presents solidā€like or liquidā€like response from the comparison of relative strengths of the relaxation time (Ļ„) and operating time (t). In the process of degradation, both the storage (Eā€²) and loss modulus (Eā€³), which represent the elastic and viscous components, respectively, decrease accordingly, reflecting the deterioration of coating. The majority of the water molecules absorbed in a coating are strongly bound to the polymer network through hydrogen bonds with polar functional groups, which destroys intermolecular bonding between macromolecules and reduces the bulk materialsā€™ ability to diffuse stress concentrations and thereby lowers a coatingā€™s overall strength

    High MYC mRNA expression is more clinically relevant than MYC DNA amplification in triple-negative breast cancer

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    DNA abnormalities are used in inclusion criteria of clinical trials for treatments with specific targeted molecules. MYC is one of the most powerful oncogenes and is known to be associated with triple-negative breast cancer (TNBC). Its DNA amplification is often part of the targeted DNA-sequencing panels under the assumption of reflecting upregulated signaling. However, it remains unclear if MYC DNA amplification is a surrogate of its upregulated signaling. Thus, we investigated the difference between MYC DNA amplification and mRNA high expression in TNBCs utilizing publicly available cohorts. MYC DNA amplified tumors were found to have various mRNA expression levels, suggesting that MYC DNA amplification does not always result in elevated MYC mRNA expression. Compared to other subtypes, both MYC DNA amplification and mRNA high expression were more frequent in the TNBCs. MYC mRNA high expression, but not DNA amplification, was significantly associated with worse overall survival in the TNBCs. The TNBCs with MYC mRNA high expression enriched MYC target genes, cell cycle related genes, and WNT/Ī²-catenin gene sets, whereas none of them were enriched in MYC DNA amplified TNBCs. In conclusion, MYC mRNA high expression, but not DNA amplification, reflects not only its upregulated signaling pathway, but also clinical significance in TNBCs

    The ubiquitin E3 ligase activity of BRCA1 and its biological functions

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    The basal-like breast cancer, a new category of breast cancer associated with poor prognosis and possibly unique chemosensitivity, is a current topic in the breast cancer field. Evidence from multiple sources strongly indicate that impairment of BRCA1 pathways is responsible for this phenotype, implying the importance of BRCA1 not only in familial breast cancers but also in sporadic cancers. BRCA1 acts as a hub protein that coordinates a diverse range of cellular pathways to maintain genomic stability. BRCA1 participates in multiple cellular supercomplexes to execute its tasks and, in most of the complexes, BRCA1 exists as a RING heterodimer with BARD1 to provide ubiquitin E3 ligase activity that is required for its tumor suppressor function. It was revealed recently that the BRCA1 RING finger is capable of catalyzing multiple types of ubiquitination depending upon the interacting E2, the ubiquitin carrier protein. BRCA1 may catalyze distinct ubiquitination on different substrates as the situation demands. On the other hand, in response to DNA double-strand breaks where BRCA1 plays its major role for homologous recombination repair, recent evidence showed that ubiquitination is a critical step to recruit BRCA1 to the damaged site through UIM (ubiquitin interacting motif) containing protein RAP80. Thus, ubiquitin and BRCA1 likely affect each other in many ways to perform cellular functions. Elucidation of this mechanism in relation to cell survival is now much anticipated because it could be a key to predict chemosensitivity of basal-like breast cancer

    A marker tephra bed close to the Lower-Middle Pleistocene boundary: Distribution of the Ontake-Byakubi Tephra Bed in central Japan

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    Tephrochronology is an exceptionally important tool in the precise regional correlation of Early and Middle Pleistocene sedimentary strata in Japan. The present study reveals that the Yukawa tephra 5 (YUT5) derived from the Older Ontake volcano, the Nezumigawa (Nzg) and Mitamitajima (Mtj) tephras of the Ina Bazin, and the Byakubi-E tephra (Byk-E) of the Boso Peninsula are the same tephra on the basis of their lithofacies, bulk grain composition, mafic mineral composition, major element composition of hornblende, and stratigraphic relationships with the dated tephras. We propose to call the series of tephras correlated with Byk-E the Ontake-Byakubi Tephra Bed (On-Byk Tephra) following the naming convention in which the tephra name consists of the names of the source volcano and the type location. The Matuyama-Brunhes Chronozone boundary occurs just above Byk-E in the type section of the Kokumoto Formation in the Kazusa Group, which is a candidate Global Boundary Stratotype Section and Point (GSSP) for the lower boundary of the Middle Pleistocene Subseries. Therefore, On-Byk Tephra becomes a critically important marker tephra bed for the Early-Middle Pleistocene boundary in central Japan. The present study indicates that the major element composition of hornblende can be a useful tool for identification and correlation of strongly weathered tephra layers such as Nzg and Mtj in which all the volcanic glass shards have been altered.ArticleQuaternary International. 397: 27-38(2016)journal articl

    Wortmannin, a specific inhibitor of phosphatidylinositol-3-kinase, induces accumulation of DNA double-strand breaks

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    Wortmannin, a fungal metabolite, is a specific inhibitor of the phosphatidylinositol 3-kinase (PI3K) family, which includes double-stranded DNA dependent protein kinase (DNA-PK) and ataxia telangiectasia mutated kinase (ATM). We investigated the effects of wortmannin on DNA damage in DNA-PK-deficient cells obtained from severe combined immunodeficient mice (SCID cells). Survival of wortmannin-treated cells decreased in a concentration-dependent manner. After treatment with 50 Ī¼M wortmannin, survival decreased to 60% of that of untreated cells. We observed that treatment with 20 and 50 Ī¼M wortmannin induced DNA damage equivalent to that by 0.37 and 0.69 Gy, respectively, of Ī³-ray radiation. The accumulation of DNA double-strand breaks (DSBs) in wortmannin-treated SCID cells was assessed using pulsed-field gel electrophoresis. The maximal accumulation was observed 4 h after treatment. Moreover, the presence of DSBs was confirmed by the ability of nuclear extracts from Ī³-ray-irradiated SCID cells to produce in vitro phosphorylation of histone H2AX. These results suggest that wortmannin induces cellular toxicity by accumulation of spontaneous DSBs through inhibition of ATM

    Application of the High Early Strength Type Expansive Agent to the Blast Furnace Slag Combination Concrete with GGBFS under Steam Curing

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    In recent years, the use of blast furnace slag material is being focused as environmental loading reduction and sustainable construction. However, in general, autogeneours shrinkage of the concrete using much amount of GGBFS is large in compared to normal concrete, therefore risk of cracking should be cared. On the other hand, strength development speed of concrete at early stage will be decreasing as the dosage of GGBFS increases, even under steam curing condition. It can be considered these points will be significant disadvantage in both productivity and quality of precast concrete. So in this study, early strength type expansive agent and setting accelerator were used in combination. As a result, it was confirmed that compressive strength at early stage is obviously increased. And steam curing temperature can be reduced about 10 degrees, and also, 600Ɨ10-6 of restraint expansion was obtained

    Evaluation of Preoperative Magnetic Resonance Cholangiopancreatography in Acute Cholecystitis to Predict Technical Difficulties in Laparoscopic Cholecystectomy

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    Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging technique that provides high-quality visualization of the biliary tree, including the gallbladder. This study aimed to evaluate the useful-ness of preoperative MRCP for acute cholecystitis in predicting technical difficulties during laparoscopic chole-cystectomy (LC). A total of 168 patients who underwent LC with preoperative MRCP were enrolled in this study. Patients were divided into two groups according to preoperative MRCP findings: the visualized group (n = 126), in which the entire gallbladder could be visualized; and the non-visualized group (n = 42), in which the entire gallbladder could not be visualized. The perioperative characteristics and postoperative complica-tions of the two groups were retrospectively analyzed. Operation time was longer in the non-visualized group (median 101.5 vs. 143.5 min; p < 0.001). The non-visualized group had significantly more intraoperative blood loss than the visualized group (median 5 vs. 10 g; p = 0.05). The rate of conversion to open cholecystectomy was significantly higher in the non-visualized group (1.6 vs. 9.5%; p = 0.03). In conclusion, patients in the non- visualized group showed higher difficulty in performance of LC. Our MRCP-based classification is a simple and effective means of predicting difficulties in performing LC for acute cholecystitis

    Deep Learning Predicts Rapid Over-softening and Shelf Life in Persimmon Fruits

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    In contrast to the progress in the research on physiological disorders relating to shelf life in fruit crops, it has been difficult to non-destructively predict their occurrence. Recent high-tech instruments have gradually enabled non-destructive predictions for various disorders in some crops, while there are still issues in terms of efficiency and costs. Here, we propose application of a deep neural network (or simply deep learning) to simple RGB images to predict a severe fruit disorder in persimmon, rapid over-softening. With 1,080 RGB images of ā€˜Soshuā€™ persimmon fruits, three convolutional neural networks (CNN) were examined to predict rapid over-softened fruits with a binary classification and the date to fruit softening. All of the examined CNN models worked successfully for binary classification of the rapid over-softened fruits and the controls with > 80% accuracy using multiple criteria. Furthermore, the prediction values (or confidence) in the binary classification were correlated to the date to fruit softening. Although the features for classification by deep learning have been thought to be in a black box by conventional standards, recent feature visualization methods (or ā€œexplainableā€ deep learning) has allowed identification of the relevant regions in the original images. We applied Grad-CAM, Guided backpropagation, and layer-wise relevance propagation (LRP), to find early symptoms for CNNs classification of rapid over-softened fruits. The focus on the relevant regions tended to be on color unevenness on the surface of the fruit, especially in the peripheral regions. These results suggest that deep learning frameworks could potentially provide new insights into early physiological symptoms of which researchers are unaware
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