The reduction of regional cerebral blood flow in normal-appearing white matter is associated with the severity of white matter lesions in elderly: a Xeon-CT study.

White matter lesions (WMLs) in normal elderly are related to chronic ischemia, and progression of WML occurs mostly in moderate to severe disease. However, the mechanism is uncertain. Thus, we enrolled fifty-six normal elderly patients without large artery disease. The severity of WML on MRI was graded as grade 0, I, II and III using the modified Fazekas scale. Cerebral blood flow (CBF) was measured by Xenon-CT. We found that CBF (mL/100 g/min) within periventricular lesions and in the right and left centrum semiovales were 20.33, 21.27 and 21.03, respectively, in group I; 16.33, 15.55 and 15.91, respectively, in group II; and 14.05, 14.46 and 14.23, respectively, in group III. CBF of normal-appearing white matter (NAWM) around periventricular areas and in the right and left centrum semiovales were 20.79, 22.26 and 22.15, respectively, in group 0; 21.12, 22.17 and 22.25, respectively, in group I; 18.02, 19.45 and 19.62, respectively, in group II; and 16.38, 18.18 and 16.74, respectively, in group III. Significant reductions in CBF were observed not only within lesions but also in NAWM surrounding the lesions. In addition, CBF was reduced significantly within lesions compared to NAWM of the same grade. Furthermore, CBF was reduced significantly in NAWM in grades II and III when compared to grades 0 and I. Our finding indicates that ischemia may play a role in the pathogenesis of WML. Additionally, our finding provides an alternative explanation for finding that the progression of WML occurred more commonly in patients with moderate to severe WML

Sputtering parameters effect on microstructural parameters of TiN coating via the Williamson-Hall analysis

Titanium nitride (TiN) coatings were deposited on Zr-4 substrate by direct current magnetron sputtering. The microstructural property of the as-deposited coating was studied by means of x-ray diffraction (XRD). The microstructural parameters, such as crystal size, lattice strain, lattice deformation stress and lattice deformation energy density, were investigated in detail by employed modified Debye–Scherrer method (MDS) and Williamson-Hall methods by assuming three models namely uniform deformation model, uniform stress deformation model and uniform energy density deformation model. And the effects of sputtering power, substrate temperature and substrate bias on microstructural parameters were investigated. The results show that TiN coating deposited by magnetron sputtering presents lattice compressive strain, except for sample X3 - 1 which is prepared by substrate bias of −50 V. It is also shown that sputtering power, substrate temperature and substrate bias have great influence on crystal size, lattice strain, lattice deformation stress and lattice deformation energy density of the as-deposited TiN coating. Especially the influence of substrate bias is very significant

Flair imaging, normal CT and Xe-CT at different levels of subjects with WML.

<p>Flair imaging, normal CT and Xe-CT at different levels of subjects with WML.</p

Mean (SD) CBF values (mL/100 g/min) in different area in each grade.

<p>P* refers to CBF comparison between different areas in the same group. NAWM means normal-appearing white matter, WPV means whole periventricular areas; RCS means right centrum semiovale, LCS means left centrum semiovale.</p><p>Mean (SD) CBF values (mL/100 g/min) in different area in each grade.</p

Clinical characteristics of all participants (n = 56) in each grade.

<p>*Compared among the four groups.</p><p>Clinical characteristics of all participants (n = 56) in each grade.</p

Mean (SD) CBF values (mL/100 g/min) of grey matter regions in each grade.

1<p>Compared with grades 0 and I, CBF in grades II and III, P value <0.05;</p>2<p>compared with grade II, CBF in grade III, P value <0.05. R means right side, L means left side.</p><p>Mean (SD) CBF values (mL/100 g/min) of grey matter regions in each grade.</p

Mean (SD) CBF (mL/100 g/min) of NAWM and lesions in each grade.

<p>P* refers to CBF within lesions compared that in NAWM in the same group.</p>1<p>Compared with grades 0 and I, CBF of NAWM in grades II and III, P value <0.05;</p>2<p>compared with grade II, CBF of NAWM in grade III, P value <0.05.</p>3<p>Compared with grade I, CBF within lesions in groups II and III, P value <0.05;</p>4<p>compared with grade II, CBF within lesions in group III, P value <0.05.</p><p>NAWM means normal-appearing white matter. RLV means right lateral of ventricle, LLV means left lateral of ventricle; RAV means right anterior of ventricle, LAV means left anterior of ventricle; RPV means right posterior of ventricle, LPV means left posterior of ventricle; WPV means whole periventricular areas; RCS means right centrum semiovale, LCS means left centrum semiovale.</p><p>Mean (SD) CBF (mL/100 g/min) of NAWM and lesions in each grade.</p

Genome-wide analysis of the strigolactone biosynthetic and signaling genes in grapevine and their response to salt and drought stresses

Strigolactones (SLs) are a novel class of plant hormones that play critical roles in regulating various developmental processes and stress tolerance. Although the SL biosynthetic and signaling genes were already determined in some plants such as Arabidopsis and rice, the information of SL-related genes in grapevine (Vitis vinifera L.) remains largely unknown. In this study, the SL-related genes were identified from the whole grapevine genome, and their expression patterns under salt and drought stresses were determined. The results indicated that the five genes that involved in the SL biosynthesis included one each of the D27, CCD7, CCD8, MAX1 and LBO genes, as well as the three genes that involved in the SL signaling included one each of the D14, MAX2, D53 genes. Phylogenetic analysis suggested that these SL-related proteins are highly conserved among different plant species. Promoter analysis showed that the prevalence of a variety of cis-acting elements associated with hormones and abiotic stress existed in the promoter regions of these SL-related genes. Furthermore, the transcription expression analysis demonstrated that most SL-related genes are involved in the salt and drought stresses response in grapevine. These findings provided valuable information for further investigation and functional analysis of SL biosynthetic and signaling genes in response to salt and drought stresses in grapevine

Spatiotemporal Dynamics of Terrestrial Vegetation and Its Driver Analysis over Southwest China from 1982 to 2015

Global environmental changes have been dramatic recently, exerting substantial effects on the structures and functions of terrestrial ecosystems, especially for the ecologically-fragile karst regions. Southwest China is one of the largest karst continuum belts around the world, which also contributes about 1/3 of terrestrial carbon sequestration to China. Therefore, a deep understanding of the long-term changes of vegetation across Southwest China over the past decades is critical. Relying on the long time series of Advanced Very High Resolution Radiometer (AVHRR) Global Inventory Modeling and Mapping Studies normalized difference vegetation index (GIMMS NDVI3g) data set, this study examined the spatial and temporal patterns of vegetation conditions in Southwest China from 1982 to 2015, as well as their response to the environmental factors including temperature, precipitation and downward shortwave radiation. Multi-year mean NDVI showed that except the northwestern region, the NDVI of Southwest China was large, ranging from 0.5 to 0.8. Meanwhile, nearly 43.7% of the area experienced significant improvements in NDVI, whereas only 3.47% of the area exhibited significant decreases in NDVI. Interestingly, the NDVI in karst area increased more quickly with 1.035 × 10−3/a in comparison with that in the non-karst area with about 0.929 × 10−3/a. Further analysis revealed that temperature is the dominant environmental factor controlling the interannual changes in NDVI, accounting for 48.19% of the area, followed by radiation (3.71%) and precipitation (3.09%), respectively