Cortical lesions are common and often extensive in multiple sclerosis but are difficult to visualize by MRI, leaving important questions about their clinical implications and response to therapy ...unanswered. Our aim was to determine whether cortical lesions are better visualized using magnetization prepared 2 rapid acquisition gradient echoes (MP2RAGE) than T2*-weighted imaging on 7T MR imaging.
Brain MR imaging using T1-weighted MP2RAGE at 500-μm isotropic resolution, T2*-weighted gradient-echo, and T2*-weighted segmented echo-planar imaging sequences were collected for 13 patients with MS and 5 age-matched neurologically healthy controls on a 7T research system. One MS case underwent postmortem MR imaging including gradient-echo and MP2RAGE sequences, after which cortical lesions seen on MR imaging were assessed with immunohistochemistry.
MP2RAGE detected 203 cortical lesions (median, 16 lesions/case; interquartile range, 15), compared to 92 with T2*gradient-echo (median, 7; interquartile range, 8;
< .001) and 81 with T2*EPI (median, 7; interquartile range, 5;
< .001). This increase in lesion number detected on MP2RAGE versus T2* was observed for juxtacortical, leukocortical, and intracortical lesions. Forty-three percent of all cortical lesions were identified only on MP2RAGE. White matter lesion volume correlated with total juxtacortical (
= 0.86,
< .001) and leukocortical lesion volume (
= 0.70,
< .01) but not intracortical lesion volume, suggesting that pathophysiology may differ by lesion type. Of 4 suspected lesions seen on postmortem imaging, 3 were found to be true cortical lesions while 1 represented postmortem tissue damage.
A combination of MP2RAGE and T2*-weighted imaging at 7T improved detection of cortical lesions and should enable longitudinal studies to elucidate their spatiotemporal dynamics and clinical implications.
Summary
Autoimmune diseases are a major cause of morbidity, and their incidence and prevalence continue to rise. Treatments for these diseases are non‐specific and result in significant adverse ...effects. Targeted therapies may help in improving the risk : benefit ratio associated with treatment. Immunological memory is an important feature of the vertebrate immune system that results in the production of cells that are long‐lived and able to respond to antigens in a more robust manner. In the setting of autoimmunity this characteristic becomes detrimental due to the ongoing response to a self‐antigen(s). These memory cells have been shown to play key roles in various autoimmune diseases such as type 1 diabetes, multiple sclerosis and psoriasis. Memory T cells and B cells can be identified based on various molecules expressed on their surface. Memory T cells can be divided into three main categories – central memory, effector memory and resident memory cells. These subsets have different proliferative potential and cytokine‐producing abilities. Utilizing differentially expressed surface molecules or downstream signalling pathway proteins in these cells it is now possible to target memory cells while sparing naive cells. We will discuss the various available options for such a strategy and several potential strategies that may yield successful therapies in the future.
Three novel bacterial strains, PVAS-1(T), B3W22(T) and B8W22(T), were isolated from cryotubes used to collect air samples at altitudes of between 27 and 41 km. Based on phenotypic characteristics, ...chemotaxonomic features, DNA-DNA hybridization with the nearest phylogenetic neighbours and phylogenetic analysis based on partial 16S rRNA gene sequences (PVAS-1(T), 1196 nt; B3W22(T), 1541 nt; B8W22(T), 1533 nt), the three strains were identified as representing novel species, and the names proposed are Janibacter hoylei sp. nov. (type strain PVAS-1(T) =MTCC 8307(T) =DSM 21601(T) =CCUG 56714(T)), Bacillus isronensis sp. nov. (type strain B3W22(T) =MTCC 7902(T) =JCM 13838(T)) and Bacillus aryabhattai sp. nov. (type strain B8W22(T) =MTCC 7755(T) =JCM 13839(T)).
Response of reinforced concrete structures subjected to blast load of high intensity and short duration is difficult to analyze. P-I (pressure-impulse) curves are one of the approaches for describing ...structural response against blast load. Design codes also suggest preparing P-I curves based on SDOF for obtaining structural response subjected to blast. Blast load excites higher modes of vibrations. The SDOF analysis does not cover the higher modes effect.The structural dynamic response of RC flexure members under a varying range of explosion scenarios was predicted by carrying out investigations. The linear elastic beam with variable boundary conditions was analyzed using the Modal superposition method based upon Euler-Bernoulli, Rayleigh, Shear, and Timoshenko theories. For various ranges of the blast, Iso-damage (P-I) curves, including the effect of higher modes, were generated, and the types of failure were established. These iso-damage curves differ significantly from those obtained using the SDOF concept for the case of blast in the dynamic and impulsive regime. In the case of near blast, understandably higher modes (both flexure and shear) play a significant role. The present study suggests that the Timoshenko formulation yields an accurate response irrespective of the Flexibility of the structure.
Four novel bacterial strains were isolated from cryogenic tubes used to collect air samples at altitudes of 24, 28 and 41 km. The four strains, 24K(T), 28K(T), 41KF2a(T) and 41KF2b(T), were ...identified as members of the genus Bacillus. Phylogenetic analysis based on 16S rRNA gene sequences indicated that three of the strains, 24K(T), 28K(T) and 41KF2a(T), are very similar to one another (>98 % sequence similarity) and show a similarity of 98-99 % with Bacillus licheniformis and 98 % with Bacillus sonorensis. DNA-DNA hybridization studies showed that strains 24K(T), 28K(T) and 41KF2a(T) exhibit <70 % similarity with each other and with B. licheniformis and B. sonorensis. Differences in phenotypic and chemotaxonomic characteristics between the novel strains and B. licheniformis and B. sonorensis further confirmed that these three isolates are representatives of three separate novel species. Strain 41KF2b(T) showed 100 % 16S rRNA gene sequence similarity to Bacillus pumilus, but differed from its nearest phylogenetic neighbour in a number of phenotypic and chemotaxonomic characteristics and showed only 55 % DNA-DNA relatedness. Therefore, the four isolates represent four novel species for which the names Bacillus aerius sp. nov. (type strain, 24K(T)=MTCC 7303(T)=JCM 13348(T)), Bacillus aerophilus sp. nov. (type strain, 28K(T)=MTCC 7304(T)=JCM 13347(T)), Bacillus stratosphericus sp. nov. (type strain, 41KF2a(T)=MTCC 7305(T)=JCM 13349(T)) and Bacillus altitudinis sp. nov. (type strain, 41KF2b(T)=MTCC 7306(T)=JCM 13350(T)) are proposed.
Isothermal sintering behavior of pure molybdenum (Mo) and mechanically alloyed Mo–TZM (Mo–0.6Ti–0.2Zr–0.02C) has been investigated in the temperature range 1000–1800
°C. A linear relationship has ...been found to exist between logarithms of increment in density and time. Although the volume diffusion has been found to be the dominant sintering mechanism, a significant contribution from grain boundary diffusion is also identified. Both the diffusion coefficients (
D
v
) obtained from shrinkage data and the grain boundary mobility (
M
b
) during grain growth are found to be lower for Mo–TZM due to the presence of carbides in the microstructure. The grain boundary migration is restricted due to the presence of carbides and porosities in the microstructure.
The paper presents an experimental and finite element investigation to explore the influence of target to projectile diameter ratio (D/d) on the ballistic performance and failure mechanism of thin ...aluminium plates. 1100-H12 aluminium target plates of 1 mm thickness were impacted by 19 mm diameter ogive and blunt nosed projectiles. The D/d ratio was varied by varying the span diameter of the target keeping the projectile diameter constant, 19 mm. The finite element simulations were carried out at D/d ratios 3.6, 5, 7.9, 10, 15, 20, 25, 30, 35 and 40. The validation of the simulation results was carried out by performing experiments at D/d ratio 3.6, 5, 7.9, 10 and 15.
The total work done in plastic deformation of the target was disintegrated into circumferential, radial, axial and tangential stretching. An initial increment in D/d ratio from 3.6 to 10 has been found to have prominent effect on the ballistic limit particularly against blunt nosed projectile. Subsequent increase in the D/d ratio however, could not influence the ballistic resistance significantly. The energy absorption inplastic deformation was found maximum for D/d ratio 10. The maximum energy dissipation occurred in circumferential stretching against bunt and in tangential stretching against ogive nosed projectile. The minimum energy dissipated in axial stretching against both the projectile.
•Ballistic performance and energy dissipation in thin aluminium targets was studied.•Target to projectile diameter ratio was varied, 3.6–40, by varying target diameter.•Ballistic limit increased with increase in target to projectile diameter ratio (D/d).•Against ogive nosed projectile maximum energy dissipated in tangential stretching.•Against blunt projectile, circumferential and radial stretching was more prominent.
Photocatalytic degradation of toxic organic pollutants is a major task in ecological and environmental protection. A lot of work has been done on photocatalytic degradation and observed that iron ...oxide composite photocatalytic systems are best suitable single-component semiconductor oxides that have low activity under visible light. In this study, iron oxide carbon composite was fabricated using iron oxide and sucrose as soluble source of carbon and annealed at 1000 and 1100°C respectively. Samples are charcterized by powder X-ray diffraction, scanning electron microscopy (SEM), and Raman spectroscopy. The photocatalytic activity of in-situ carbon supported iron oxide (ICS-Fe
2
O
3
) is studied for cationic dyes (MB (Methylene Blue) and CV (Crystal Violet)). Sample heat treated at 1000°C shows better photocatalytic activity than sample heat treated at 1100°C.
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