Enterovirus A-71 (EV-A71) may be fatal, but the natural history, symptoms, and signs are poorly understood. This study aimed to examine the natural history of fatal EV-A71 infection and to identify the symptoms and signs of early warning of deterioration. This was a clinical observational study of fatal cases of EV-A71 infection treated at five Chinese hospitals between 1 January 2010 and 31 December 2012. We recorded and analysed 91 manifestations of EV-A71 infection in order to identify early prognosis indicators. There were 54 fatal cases. Median age was 21.5 months (Q1−Q3: 12–36). The median duration from onset to death was 78.5 h (range, 6 to 432). The multilayer perceptron analysis showed that ataxia respiratory, ultrahyperpyrexia, excessive tachycardia, refractory shock, absent pharyngeal reflex, irregular respiratory rhythm, hyperventilation, deep coma, pulmonary oedema and/or haemorrhage, excessive hypertension, tachycardia, somnolence, CRT extension, fatigue or sleepiness and age were associated with death. Autopsy findings (n = 2) showed neuronal necrosis, softening, perivascular cuffing, colloid and neuronophagia phenomenon in the brainstem. The fatal cases of enterovirus A71 had neurologic involvement, even at the early stage. Direct virus invasion through the neural pathway and subsequent brainstem damage might explain the rapid progression to death.

High-pressure in situ angular dispersive x-ray diffraction study on the wurtzite-type InN nanowires has been carried out by means of the image-plate technique and diamond-anvil cell (DAC) up to about 31.8 GPa. The pressure-induced structural transition from the wurtzite to a rocksalt-type phase occurs at about 14.6 GPa, which is slightly higher than the transition pressure of InN bulk materials (∼12.1 GPa). The relative volume reduction at the transition point is close to 17.88%, and the bulk modulus B0 is determined through fitting the relative volume-pressure experimental data related to the wurtzite and rocksalt phases to the Birch–Murnaghan equation of states. Moreover, high-pressure Raman scattering for InN nanowires were also investigated in DAC at room temperature. The corresponding structural transition was confirmed by assignment of phonon modes. We calculated the mode Grüneisen parameters for the wurtzite and rocksalt phases of InN nanowires.

Good sample preparation is essential for acquiring successful electron backscattered diffraction (EBSD) patterns in the SEM. Mechanical polishing to obtain the required surface quality with minimal sub-surface defects and deformation that does not interfere with the quality of the diffraction data is, more often than not, an art form. Special polishing techniques, such as low force lapping fixtures, electrochemical-mechanical polishing, and vibratory polishing, have been used to minimize the sub-surface damage, but have not eliminated it. Ion polishing has been used to reduce the damage layer further. However, the commercially available ion systems suffer several drawbacks, including: 1) small area treatment (≤ 1 cm) 2) decreasing beam current density with accelerating voltages, and 3) the inability to process non-conducting samples. Barna and Pecz have shown that at 3 keV with an incident angle of 5° relative to the surface, approximately 25 nm of ion damage occurs in Si and GaAs, but at 250 eV, there is less than 1 nm of amorphization of the surface. They also showed that a glancing angle across the surface is essential for removing topographic features. The ion guns that have been available for ion polishing and ion etching of SEM samples typically cannot operate effectively below 3 keV because of the low current density.

An iron-based amorphous metal, Fe49.7Cr17.7Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 (SAM2X5), with very good corrosion resistance has been developed. This material was prepared as a melt-spun ribbon, as well as gas atomized powder and a thermal-spray coating. During electrochemical testing in several environments, including seawater at 90 °C, the passive film stability was found to be comparable to that of high-performance nickel-based alloys and superior to that of stainless steels, based on electrochemical measurements of the passive film breakdown potential and general corrosion rates. This material also performed very well in standard salt fog tests. Chromium (Cr), molybdenum (Mo), and tungsten (W) provided corrosion resistance, and boron (B) enabled glass formation. The high boron content of this particular amorphous metal made it an effective neutron absorber and suitable for criticality control applications. This material and its parent alloy maintained corrosion resistance up to the glass transition temperature and remained in the amorphous state during exposure to relatively high neutron doses.

The nucleation mechanism of deformation-induced martensite was investigated by x-ray diffraction and transmission electron microscope in an ultra-low carbon austenitic stainless steel deformed by equal channel angular pressing at room temperature. It was found that two types of martensite transformation mechanism, stress-assisted and strain-induced, occurred via the sequences of γ (fcc) → ɛ (hcp) → α′ (bcc) and/or γ → α′. In both cases, the crystallographic relationships among γ, ɛ, and α′ followed the Kurdjumov-Sachs orientation relationships: {111}γ //{0001}ɛ //{011}α′ and 〈110〉γ//〈1120〉ɛ//〈111〉α′.

Bulk fully nanocrystalline grain structures were successfully obtained in ultralow carbon stainless steel by means of equal channel angular pressing at room temperature. Transmission electron microscopy (TEM) and high-resolution TEM investigations indicated that two types of nanostructures were formed: nanocrystalline strain-induced martensite (body-centered cubic structure) with a mean grain size of 74 nm and nanocrystalline austenite (face-centered cubic structure) with a size of 31 nm characterized by dense deformation twins. The results about the formation of fully nanocrystalline grain structures in stainless steel suggested that a low stacking fault energy is exceptionally profitable for producing nanocrystalline materials by equal channel angular pressing.

We have used nanometer spatial resolution secondary electron and Auger electron imaging in an ultra-high vacuum scanning transmission electron microscope to characterize microstructure in ultrathin films of Fe/Cu(100) grown at room temperature and Fe/CaF2/Si(111) grown at room temperature and 150 C. Thin film microstructure was correlated in situ with magnetic properties by using the surface magneto-optic Kerr effect.