Stress intensity factor solution for edge interface crack based on the crack tip stress without the crack

In this paper, a new solution is discussed for the stress intensity factor of an edge interface crack. The intensity of the singular stress field (ISSF) at the interface end before appearing the edge interface crack is distinguished from the stress intensity factor (SIF) of the interface crack itself. By considering those two distinct double singular stress fields, the ISSF and the SIF are discussed under arbitrary material combinations. By focusing on the crack tip stress without the interface crack σy(a), the SIF of the edge interface crack can be expressed conveniently. This is because the crack tip stress without the interface crack is reflecting the ISSF at the interface end. The SIFs based on the crack tip stress without the interface crack are indicated by varying the crack length and material combination. It is found that the normalized SIFs (F1,int and F2,int) based on σy(a) are independent of the geometrical condition for the wide range of the crack length

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Direct volume manipulation for visualizing intraoperative liver resection process

This paper introduces a new design and application for direct volume manipulation for visualizing the intraoperative liver resection process. So far, interactive volume deformation and resection have been independently handled due to the difficulty of representing elastic behavior of volumetric objects. Our framework models global shape editing and discontinuous local deformation by merging proxy geometry encoding and displacement mapping. A local-frame-based elastic model is presented to allow stable editing of the liver shape including bending and twisting while preserving the volume. Several tests using clinical CT data have confirmed the developed software and interface can represent the intraoperative state of liver and produce local views of reference vascular structures, which provides a "road map of vessels" that are key features when approaching occluded tumors during surgery

Gated Silicon Drift Detector Fabricated from a Low-Cost Silicon Wafer

Inexpensive high-resolution silicon (Si) X-ray detectors are required for on-site surveys of traces of hazardous elements in food and soil by measuring the energies and counts of X-ray fluorescence photons radially emitted from these elements. Gated silicon drift detectors (GSDDs) are much cheaper to fabricate than commercial silicon drift detectors (SDDs). However, previous GSDDs were fabricated from $10$-k$\Omega \cdot$cm Si wafers, which are more expensive than $2$-k$\Omega \cdot$cm Si wafers used in commercial SDDs. To fabricate cheaper portable X-ray fluorescence instruments, we investigate GSDDs formed from $2$-k$\Omega \cdot$cm Si wafers. The thicknesses of commercial SDDs are up to $0.5$ mm, which can detect photons with energies up to $27$ keV, whereas we describe GSDDs that can detect photons with energies of up to $35$ keV. We simulate the electric potential distributions in GSDDs with Si thicknesses of $0.5$ and $1$ mm at a single high reverse bias. GSDDs with one gate pattern using any resistivity Si wafer can work well for changing the reverse bias that is inversely proportional to the resistivity of the Si wafer

Oral administration of bovine lactoferrin upregulates neutrophil functions in a dog with familial β2-integrin-related neutrophil dysfunction

Lactoferrin, a glycoprotein present in neutrophils and exocrine secretions, plays important roles in host defense. Administration of bovine lactoferrin has been reported to modulate various neutrophil functions. We found a mixed-breed male dog with novel familial neutrophil dysfunction. The disorder was caused by a decrease of β2-integrin expression encoding CD18 without mutation. Antibiotics therapy alone did not influence a series of neutrophil functions in the same dog. We examined the effects of oral administration of bovine lactoferrin on the neutrophil function and clinical symptoms in the same dog. Oral chronic administration of bovine lactoferrin increased neutrophilic β2-integrin gene expression comparable to normal dogs, followed by the upregulation of surface CD18 expression. Concurrently, the superoxide production, phagocytic activity and adherence that were β2-integrin-related neutrophil functions increased to normal canine levels. The chronic inflammation from bacterial upper respiratory infections and pneumonia was also alleviated in the dog. Our results indicate that oral treatment with bovine lactoferrin increases neutrophil β2-integrin transcript level, leading to the upregulation of neutrophil functions and improvement of clinical symptoms in the dog with familial neutrophil dysfunction