• Computers and Concrete
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• v.4 no.1
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• pp.67-82
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• 2007

The discrete crack-concept is applied to study the 3D propagation of tensile-dominated failure in plain concrete. To this end the Partition of Unity Finite Element Method (PUFEM) is utilized and the strong discontinuity approach is followed. A consistent linearized implementation of the PUFEM is combined with a predictor-corrector algorithm to track the crack path, which leads to a robust numerical description of concrete cracking. The proposed concept is applied to study concrete failure during the PCT3D test and the predicted numerical results are compared to experimental data. The proposed numerical concept provides a clear interface for constitutive models and allows an investigation of their impact on concrete cracking under 3D conditions, which is of significant scientific interests to interpret results from 3D experiments.

• Clinical and Experimental Pediatrics
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• v.61 no.9
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• pp.285-290
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• 2018

Purpose: To study the usefulness of the procalcitonin (PCT) test in young febrile infants between 1 and 3 months of age. Methods: We evaluated the medical records of 336 febrile infants between 1 and 3 months of age who visited the Emergency Department or outpatient department of Samsung Changwon Hospital from May 2015 to February 2017, and analyzed the clinical characteristics between infants in the serious bacterial infection (SBI) group and non-SBI group. Results: Among the 336 infants, 38 (11.3%) had definitive SBI (bacteremia, n=3; meningitis, n=1; urinary tract infection, n=34). The mean PCT ($6.4{\pm}11.9ng/mL$) and C-reactive protein (CRP) level ($3.8{\pm}2.6mg/dL$), and the absolute neutrophil count (ANC) ($6,984{\pm}4,675$) for patients in the SBI group were significantly higher than those for patients in the non-SBI group (PCT, $0.3{\pm}1.2ng/mL$; CRP, $1.3{\pm}1.6mg/dL$; ANC, $4,888{\pm}3,661$). PCT had lower sensitivity (43.6%), but higher specificity (92.6%) and accuracy (86.9%) than CRP (92.3%, 25.3%, and 33.0%) for identifying SBI. The area under the receiver operating characteristic curves (AUCs) for definitive SBI were PCT 77.0%, CRP 80.8%, WBC 56.8%, ANC 67.8%, and PLT 48.1%. The AUCs for definitive SBI were PCT+CRP 85.4%, PCT+WBC 77.2%, PCT+ANC 81.3%, CRP+WBC 80.1%, and CRP+ANC 81.6%. Conclusion: Our results suggest that the PCT test or a combination of PCT and CRP tests is a more accurate and specific biomarker to detect and rule out SBIs.

• Computers and Concrete
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• v.4 no.1
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• pp.49-66
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• 2007

The objective of this paper is to provide experimental data on the propagation of curved crack-surfaces and the respective load-displacement diagrams for the validation of numerical models for cracking of concrete, subjected to three-dimensional stress states. To this end beam-shaped specimens are subjected to combined bending and torsional loading, leading to the formation of a spatially curved crack-surface. The experimental data contain the evolution of the load and of the strains at selected points in terms of the crack mouth opening displacement and the propagation of the crack surface.