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On the exceptional damage-tolerance of gradient metallic materials
An experimental study is described on the fracture toughness and micro-mechanisms associated with the initiation and propagation of cracks in metallic nickel containing marked gradients in grain size, ranging from ∼30 nm to ∼4 μm. Specifically, cracks are grown in a gradient structured (GS) nickel with grain-size gradient ranging from the coarse macro-scale to nano-scale (CG → NG) and vice versa (NG → CG), with the measured crack-resistance R-curves compared to the corresponding behavior in uniform nano-grained (NG) and coarse-grained (CG) materials. It is found that the gradient structures display a much-improved combination of high strength and toughness compared to uniform grain-sized materials. However, based on J-integral measurements in the gradient materials, the crack-initiation toughness is far higher for cracks grown in the direction of the coarse-to-nano grained gradient than vice versa, a result which we ascribe primarily to excessive crack-tip blunting in the coarse-grained microstructure. Both gradient structures, however, display marked rising R-curve behavior with exceptional crack-growth toughnesses exceeding 200 MPa.m½
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TGFβ1 single-nucleotide polymorphism C-509T alters mucosal cell function in pediatric eosinophilic esophagitis.
Eosinophilic esophagitis (EoE) is a chronic Th2 antigen-driven disorder associated with tissue remodeling. Inflammation and remodeling lead to esophageal rigidity, strictures, and dysphagia. TGFβ1 drives esophageal remodeling including epithelial barrier dysfunction and subepithelial fibrosis. A functional SNP in the TGFβ1 gene that increases its transcription (C-509T) is associated with elevated numbers of esophageal TGFβ1-expressing cells. We utilized esophageal biopsies and fibroblasts from TT-genotype EoE children to understand if TGFβ1 influenced fibroblast and epithelial cell function in vivo. Genotype TT EoE esophageal fibroblasts had higher baseline TGFβ1, collagen1α1, periostin, and MMP2 (p < 0.05) gene expression and distinct contractile properties compared with CC genotype (n = 6 subjects per genotype). In vitro TGFβ1 exposure caused greater induction of target gene expression in genotype CC fibroblasts (p < 0.05). Esophageal biopsies from TT-genotype subjects had significantly less epithelial membrane-bound E-cadherin (p < 0.01) and wider cluster distribution at nanometer resolution. TGFβ1 treatment of stratified primary human esophageal epithelial cells and spheroids disrupted transepithelial resistance (p < 0.001) and E-cadherin localization (p < 0.0001). A TGFβ1-receptor-I inhibitor improved TGFβ1-mediated E-cadherin mislocalization. These data suggest that EoE severity can depend on genotypic differences that increase in vivo exposure to TGFβ1. TGFβ1 inhibition may be a useful therapy in subsets of EoE patients
Count three for wear able computers
This paper is a postprint of a paper submitted to and accepted for publication in the Proceedings of the IEE Eurowearable 2003 Conference, and is subject to Institution of Engineering and Technology Copyright. The copy of record is available at the IET Digital Library.
A revised version of this paper was also published in Electronics Systems and Software, also subject to Institution of Engineering and Technology Copyright. The copy of record is also available at the IET Digital Library.A description of 'ubiquitous computer' is presented. Ubiquitous computers imply portable computers embedded into everyday objects, which would replace personal computers. Ubiquitous computers can be mapped into a three-tier scheme, differentiated by processor performance and flexibility of function. The power consumption of mobile devices is one of the most important design considerations. The size of a wearable system is often a design limitation
Pengelolaan Pelabuhan Cartagena Spanyol sebagai Kerangka Optimalisasi Pelabuhan di Negeri Sendiri
Dampak ekonomi dari pengembangan Pelabuhan Cartagena sangat pesat dalam kurun waktu 10 tahun terakhir. Hal ini ditunjukkan dengan adanya kenaikan Product Domestic Regional Bruto(PDRB) sektor kelautan dengan Gross Value Added(GVA) dari nilai 1,1% menjadi 3,81% dan nilai 0,1% menjadi 2,11% untuk sektor tenaga kerja. Dengan metode Regional Input-Output Tables(R-IOT) dan metode pendekatan Input-Output(I-O) didapat data dan angka – angka yang bisa memberikan beberapa terobosan pengembangan dari sektor forex pelabuhan maupun sektor pariwisata maritim, sehingga Pelabuhan Cartagena sebagai pemberi impact terbesar ke 5 dari 28 pelabuhan yang ada di Spanyol dan menempatkan Spanyol menduduki peringkat 2 dalam hal kedatangan turis dengan kapal pesiar di Eropa setelah Italia.Indonesia juga mencontoh dengan strategi yang sama sektor-sektor yang mempengaruhi PDRB,tenaga kerja pada sektor kelautan,keringanan bidang pajak, kemudahan bidang tenaga kerja, jaminan keamanan bagi investor yang menanam modalnya disektor kelautan, dengan didukung oleh akses-akses transportasi yang mudah, cepat, dan simpul-simpul kemacetan ditiadakan. Seluruh akses yang menuju kepusat-pusat ekonomi kelautan diperbaiki, industri pendukung baik dari sektor swasta maupun Badan Usaha Milik Negara(BUMN) juga berbenah. Indonesia mulai memandang laut sebagai masa depan,tidak lagi membelakangi laut, seluruh aktifitas dan kebijakannya bersifat sustainable .Potensi kelautan yang demikianlah yang dapat menjamin masa depan generasi mendatang menjadi lebih baik
One crash, too many : Global uncertainty, sentiment factors and cryptocurrency market
Peer reviewe
Proximal and distal esophageal contractions in patients with vigorous or classic esophageal Chagas' disease
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