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Summary: This paper presents an adaptive fuzzy control approach of multiple‐input–multiple‐output (MIMO) switched uncertain systems, which involve time‐varying full state constraints (TFSCs) and unknown disturbances. In the design procedure, the fuzzy logic systems are adopted to approximate the unknown functions in the systems. The adaptive fuzzy controller is set up by backstepping technique. According to the tangent barrier Lyapunov function (BLF‐Tan), a novel adaptive MIMO switched nonlinear control algorithm is designed. Under the rule of arbitrary switchings and the proposed control laws, it is demonstrated that all signals in the resulted system are semiglobally uniformly ultimately bounded (SGUUB) and the tracking error converges to a small neighborhood of zero with TFSCs. Furthermore, the simulation example validates the effectiveness of presented control strategy. [ABSTRACT FROM AUTHOR]

Summary: This paper is concerned with adaptive tracking control for switched uncertain nonlinear systems, which contain the time‐varying output constraint (TVOC) and input asymmetric saturation characteristic. In response to the unknown functions, the fuzzy logic systems are adopted. The controller is constructed by the backstepping technique. Based on the Tangent Barrier Lyapunov Function (BLF‐Tan), an adaptive switched control scheme is designed. It is demonstrated that all signals in the resulted system are semiglobally uniformly ultimately bounded with TVOC under arbitrary switchings. Furthermore, the effectiveness of presented control method is validated via the simulation example. [ABSTRACT FROM AUTHOR]

Objectives: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is characterized by strategic white matter (WM) hyperintensities on MRI. Pathological features include WM degeneration, arteriolosclerosis, lacunar infarcts, and the deposition of granular osmiophilic material. Based on the hypothesis that the gliovascular unit is compromised, we assessed the nature of astrocyte damage in the deep WM of CADASIL subjects. Methods: We evaluated post‐mortem brains from CADASIL, cerebral small vessel disease, similar age cognitively normal and older control subjects. Standard immunohistochemical, immunofluorescent, and unbiased stereological methods were used to evaluate the distribution of astrocytes, microvessels, and autophagy markers in five different brain regions. Results: Compared to the controls, the deep WM of CADASIL subjects overall showed increased numbers of glial fibrillary acidic protein (GFAP)‐positive clasmatodendritic astrocytes (P=0.037) and a decrease in the percentage of normal appearing astrocytes (P=0.025). In accord with confluent WM hyperintensities, the anterior temporal pole contained abundant clasmatodendritic astrocytes with displaced aquaporin 4 immunoreactivity. Remarkably, we also found strong evidence for the immunolocalization of autophagy markers including microtubule‐associated protein 1, light chain 3 (LC3), and sequestosome 1/p62 and Caspase‐3 in GFAP‐positive clasmatodendritic cells, particularly within perivascular regions of the deep WM. LC3 was co‐localized in more than 90% of the GFAP‐positive clasmatodendrocytes. Conclusions: Our novel findings show astrocytes undergo autophagy‐like cell death in CADASIL, with the anterior temporal pole being highly vulnerable. We propose astrocytes transform from normal appearing type A to hypertrophic type B and eventually to clasmatodendritic type C cells. These observations also suggest the gliovascular unit of the deep WM is severely impaired in CADASIL. [ABSTRACT FROM AUTHOR]

This study aimed to quantify blood pressure (BP) measurement accuracy and variability with different techniques. Thirty video clips of BP recordings from the BHS training database were converted to Korotkoff sound waveforms. Ten observers without receiving medical training were asked to determine BPs using (a) traditional manual auscultatory method and (b) visual auscultation method by visualizing the Korotkoff sound waveform, which was repeated three times on different days. The measurement error was calculated against the reference answers, and the measurement variability was calculated from the SD of the three repeats. Statistical analysis showed that, in comparison with the auscultatory method, visual method significantly reduced overall variability from 2.2 to 1.1 mmHg for SBP and from 1.9 to 0.9 mmHg for DBP (both p<0.001). It also showed that BP measurement errors were significant for both techniques (all p<0.01, except DBP from the traditional method). Although significant, the overall mean errors were small (−1.5 and −1.2 mmHg for SBP and −0.7 and 2.6 mmHg for DBP, resp., from the traditional auscultatory and visual auscultation methods). In conclusion, the visual auscultation method had the ability to achieve an acceptable degree of BP measurement accuracy, with smaller variability in comparison with the traditional auscultatory method. [ABSTRACT FROM AUTHOR]

This study aimed to compare within-subject blood pressure (BP) variabilities from different measurement techniques. Cuff pressures from three repeated BP measurements were obtained from 30 normotensive and 30 hypertensive subjects. Automatic BPs were determined from the pulses with normalised peak amplitude larger than a threshold (0.5 for SBP, 0.7 for DBP, and 1.0 for MAP). They were also determined from cuff pressures associated with the above thresholds on a fitted curve polynomial curve of the oscillometric pulse peaks. Finally, the standard deviation (SD) of three repeats and its coefficient of variability (CV) were compared between the two automatic techniques. For the normotensive group, polynomial curve fitting significantly reduced SD of repeats from 3.6 to 2.5 mmHg for SBP and from 3.7 to 2.1 mmHg for MAP and reduced CV from 3.0% to 2.2% for SBP and from 4.3% to 2.4% for MAP (all P<0.01). For the hypertensive group, SD of repeats decreased from 6.5 to 5.5 mmHg for SBP and from 6.7 to 4.2 mmHg for MAP, and CV decreased from 4.2% to 3.6% for SBP and from 5.8% to 3.8% for MAP (all P<0.05). In conclusion, polynomial curve fitting of oscillometric pulses had the ability to reduce automatic BP measurement variability. [ABSTRACT FROM AUTHOR]

Aim Brain clusterin is known to be associated with the amyloid-β deposits in Alzheimer's disease ( AD). We assessed the distribution of clusterin immunoreactivity in cerebrovascular disorders, particularly focusing on white matter changes in small vessel diseases. Methods Post-mortem brain tissues from the frontal or temporal lobes of a total of 70 subjects with various disorders including cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy ( CADASIL), cerebral amyloid angiopathy ( CAA) and AD were examined using immunohistochemistry and immunofluorescence. We further used immunogold electron microscopy to study clusterin immunoreactivity in extracellular deposits in CADASIL. Results Immunostaining with clusterin antibodies revealed strong localization in arterioles and capillaries, besides cortical neurones. We found that clusterin immunostaining was significantly increased in the frontal white matter of CADASIL and pontine autosomal dominant microangiopathy and leukoencephalopathy subjects. In addition, clusterin immunostaining correlated with white matter pathology severity scores. Immunostaining in axons ranged from fine punctate deposits in single axons to larger confluent areas with numerous swollen axon bulbs, similar to that observed with known axon damage markers such as non-phosphorylated neurofilament H and the amyloid precursor protein. Immunofluorescence and immunogold electron microscopy experiments showed that whereas clusterin immunoreactivity was closely associated with vascular amyloid-β in CAA, it was lacking within the granular osmiophilic material immunolabelled by NOTCH3 extracelluar domain aggregates found in CADASIL. Conclusions Our results suggest a wider role for clusterin associated with white matter damage in addition to its ability to chaperone proteins for clearance via the perivascular drainage pathways in several disease states. [ABSTRACT FROM AUTHOR]

Propagating optical eigenmodes are found in densely packed monolayers of plasmonic nanoparticles on a metal mirror. FDTD numerical calculations show that these 2D waves carry strongly confined and amplified light energy directly in the layer of nanoparticles or in the gap between the nanoparticles and the mirror. The extreme amplification of light intensity and localization at the nanoscale offer a high potential of these waves for photon emission, light harvesting, and waveguiding applications. [ABSTRACT FROM AUTHOR]

The article describes research report on Detrital Zircon U-Pb Geochronology of the Triassic Sandstones from the Yanyuan Basin of Southwestern Sichuan, China. Topics discusses include Triassic sandstones in the Yanyuan Basin record different detrital zircon geochronology signals; and supported by the Sichuan Science and technology program the open fund of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology.