Nuclear Inelastic X-Ray Scattering of FeO to 48 GPa

The partial density of vibrational states has been measured for Fe in compressed FeO (w\"ustite) using nuclear resonant inelastic x-ray scattering. Substantial changes have been observed in the overall shape of the density of states close to the magnetic transiton around 20 GPa from the paramagnetic (low pressure) to the antiferromagnetic (high pressure) state. Our data indicate a substantial softening of the aggregate sound velocities far below the transition, starting between 5 and 10 GPa. This is consistent with recent radial x-ray diffraction measurements of the elastic constants in FeO. The results indicate that strong magnetoelastic coupling in FeO is the driving force behind the changes in the phonon spectrum of FeO.Comment: 4 pages, 4 figure

An empirical comparison of commercial and open‐source web vulnerability scanners

Web vulnerability scanners (WVSs) are tools that can detect security vulnerabilities in web services. Although both commercial and open-source WVSs exist, their vulnerability detection capability and performance vary. In this article, we report on a comparative study to determine the vulnerability detection capabilities of eight WVSs (both open and commercial) using two vulnerable web applications: WebGoat and Damn vulnerable web application. The eight WVSs studied were: Acunetix; HP WebInspect; IBM AppScan; OWASP ZAP; Skipfish; Arachni; Vega; and Iron WASP. The performance was evaluated using multiple evaluation metrics: precision; recall; Youden index; OWASP web benchmark evaluation; and the web application security scanner evaluation criteria. The experimental results show that, while the commercial scanners are effective in detecting security vulnerabilities, some open-source scanners (such as ZAP and Skipfish) can also be effective. In summary, this study recommends improving the vulnerability detection capabilities of both the open-source and commercial scanners to enhance code coverage and the detection rate, and to reduce the number of false-positives

Chinese and Korean Characters Engage the Same Visual Word Form Area in Proficient Early Chinese-Korean Bilinguals

A number of recent studies consistently show an area, known as the visual word form area (VWFA), in the left fusiform gyrus that is selectively responsive for visual words in alphabetic scripts as well as in logographic scripts, such as Chinese characters. However, given the large difference between Chinese characters and alphabetic scripts in terms of their orthographic rules, it is not clear at a fine spatial scale, whether Chinese characters engage the same VWFA in the occipito-temporal cortex as alphabetic scripts. We specifically compared Chinese with Korean script, with Korean script serving as a good example of alphabetic writing system, but matched to Chinese in the overall square shape. Sixteen proficient early Chinese-Korean bilinguals took part in the fMRI experiment. Four types of stimuli (Chinese characters, Korean characters, line drawings and unfamiliar Chinese faces) were presented in a block-design paradigm. By contrasting characters (Chinese or Korean) to faces, presumed VWFAs could be identified for both Chinese and Korean characters in the left occipito-temporal sulcus in each subject. The location of peak response point in these two VWFAs were essentially the same. Further analysis revealed a substantial overlap between the VWFA identified for Chinese and that for Korean. At the group level, there was no significant difference in amplitude of response to Chinese and Korean characters. Spatial patterns of response to Chinese and Korean are similar. In addition to confirming that there is an area in the left occipito-temporal cortex that selectively responds to scripts in both Korean and Chinese in early Chinese-Korean bilinguals, our results show that these two scripts engage essentially the same VWFA, even at the level of fine spatial patterns of activation across voxels. These results suggest that similar populations of neurons are engaged in processing the different scripts within the same VWFA in early bilinguals

Structural Modifications of the Brain in Acclimatization to High-Altitude

Adaptive changes in respiratory and cardiovascular responses at high altitude (HA) have been well clarified. However, the central mechanisms underlying HA acclimatization remain unclear. Using voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) with fractional anisotropy (FA) calculation, we investigated 28 Han immigrant residents (17–22 yr) born and raised at HA of 2616–4200 m in Qinghai-Tibetan Plateau for at least 17 years and who currently attended college at sea-level (SL). Their family migrated from SL to HA 2–3 generations ago and has resided at HA ever since. Control subjects were matched SL residents. HA residents (vs. SL) showed decreased grey matter volume in the bilateral anterior insula, right anterior cingulate cortex, bilateral prefrontal cortex, left precentral cortex, and right lingual cortex. HA residents (vs. SL) had significantly higher FA mainly in the bilateral anterior limb of internal capsule, bilateral superior and inferior longitudinal fasciculus, corpus callosum, bilateral superior corona radiata, bilateral anterior external capsule, right posterior cingulum, and right corticospinal tract. Higher FA values in those regions were associated with decreased or unchanged radial diffusivity coinciding with no change of longitudinal diffusivity in HA vs. SL group. Conversely, HA residents had lower FA in the left optic radiation and left superior longitudinal fasciculus. Our data demonstrates that HA acclimatization is associated with brain structural modifications, including the loss of regional cortical grey matter accompanied by changes in the white matter, which may underlie the physiological adaptation of residents at HA