RESUMO
Here, we present a protocol for preparing layer-engineered van der Waals (vdW) materials via an atomic spalling process. We describe steps for fixing bulk crystals and introduce the appropriate stressor materials. We then detail a deposition technique for internal stress regulation of stressor film, followed by layer-engineered atomic-scale spalling to exfoliate vdW materials with a controlled number of layers from bulk crystals. Lastly, we outline a procedure for polymer/stressor film removal. For complete details on the use and execution of this protocol, please refer to Moon et al.1.
RESUMO
Bowel ischemia is a life-threatening surgical emergency. We report a case of rapidly progressive bowel necrosis in a previously healthy child without proven mechanical small bowel obstruction. The definite diagnosis was established at the time of an exploratory operation. Of note, imaging studies and even a laparotomy did not reveal any evidence of acute appendicitis or mechanical obstruction such as intussusception or Meckel's diverticulum. During hospitalization, since we could not rule out surgical abdomen after inconclusive image findings, we closely followed the patient and repeated physical examinations carefully. Eventually surgical exploration was performed based on changes in clinical condition, which proved to be the right decision for the patient. We propose that in children with suspected strangulation of small bowel obstruction, especially when imaging findings do not provide a conclusive diagnosis, the timely exploratory surgical approach ought to be chosen based on carefully observed clinical findings and other evaluations.
RESUMO
The water distribution in human osteoarthritic articular cartilage has been quantitatively characterized using terahertz time-domain spectroscopy (THz TDS). We measured the refractive index and absorption coefficient of cartilage tissue in the THz frequency range. Based on our measurements, the estimated water content was observed to decrease with increasing depth cartilage tissue, showing good agreement with a previous report based on destructive biochemical methods.
RESUMO
We demonstrated quantitative analysis and measurements of near-fields interactions in a terahertz pulse near-field microscope. We developed a self-consistent line dipole image method for the quantitative analysis of the near-field interaction in THz scattering-type scanning optical microscopes. The measurements of approach curves and relative contrasts on gold and silicon substrates were in excellent agreement with calculations.