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Cerebral small vessel disease (CSVD) is characterized by widespread functional changes in the brain, as evident from abnormal brain activations during cognitive tasks. However, the existing findings in this area are not yet conclusive. We systematically reviewed 25 studies reporting task-related fMRI in five cognitive domains in CSVD, namely executive function, working memory, processing speed, motor, and affective processing. The findings highlighted: (1) CSVD affects cognitive processes in a domain-specific manner; (2) Compensatory and regulatory effects were observed simultaneously in CSVD, which may reflect the interplay between the negative impact of brain lesion and the positive impact of cognitive reserve. Combined with behavioral and functional findings in CSVD, we proposed an integrated model to illustrate the relationship between altered activations and behavioral performance in different stages of CSVD: functional brain changes may precede and be more sensitive than behavioral impairments in the early pre-symptomatic stage; Meanwhile, compensatory and regulatory mechanisms often occur in the early stages of the disease, while dysfunction/decompensation and dysregulation often occur in the late stages. Overall, abnormal hyper-/hypo-activations are crucial for understanding the mechanisms of small vessel lesion-induced behavioral dysfunction, identifying potential neuromarker and developing interventions to mitigate the impact of CSVD on cognitive function.

Purpose: Radial extracorporeal shock wave therapy (rESWT) has been used in clinical and rehabilitation fields. However, the formulation of related clinical treatment protocols and the full potential of its therapeutic efficacy are constrained due to limited understanding of shock wave sources. This study aimed to further clarify the characteristics of shock wave sources generated at different medium interfaces. Methods: Shock wave generated by rESWT device at the interface of different media (soft tissue-mimicking-phantom, water and air) was measured based on flexible polyvinylidene fluoride (PVDF) sensors. The temporal and spectral characteristics of the shock wave source were analyzed. Results: The wave generated at the phantom interface was similar to that at the water interface under the same impact pressure, both being largely different from that at the air interface, where the absolute value of the peak pressure was significantly reduced. The spectral properties of the shock wave generated in different media were similar, with distinct peak frequencies, varying modulation frequencies in phantom (12.2 kHz), water (8.5 kHz), and air (7.2 kHz), and a relatively constant carrier frequency (between 82 and 83 kHz). Under the different impact pressures, there were no variations in the peak frequency at the same medium interface, indicating that the impact pressure mainly impacts the shock wave amplitude, but not the peak frequency. Conclusion: The shock waves generated at different medium interfaces exhibited temporal and spectral differences. Therefore, measurement results in biological soft tissues cannot be simply replaced by the measurement results in air or water. The results of this study are expected to provide important information for evaluating rESWT devices and optimizing clinical shock wave treatment protocols.

Aluminum alloy wires with higher strength and better electrical conductivity are demanded in electrical engineering. Pre-torsion was employed to process aluminum alloy wire for the improvement of its properties. Uniaxial tensile and electrical tests show that simultaneous improvements of strength and electrical conductivity were achieved in the pre-torsioned aluminum alloy wire at a maximum shear strain of 0.27. Microstructural observations reveal that pre-torsion induces the formation of nanoscale rod-shaped β′ particles and the sizes of nanoscale precipitates increase with the maximum shear strain of pre-torsion. Based on the experimental results, a theoretical model is proposed to reveal the underlying mechanisms. The small nanoscale precipitates can contribute to the improvement of strength and electrical conductivity. The large size of nanoscale precipitates leads to the low strength and poor electrical conductivity. This is attributed to the weak strengthening and strong electron scattering in large nanoscale precipitates.

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Background: Vitexin is the main bioactive compound of hawthorn (Crataegus pinnatifida), a famous traditional Chinese medicine, and vitexin for injection is currently in phase I clinical trial in China. Objective: This investigation systematically evaluated the metabolism and toxicokinetics of vitexin in rats and dogs. Methods: Rats and beagle dogs were administrated different doses of vitexin, and then the plasma concentration, tissue distribution, excretion, metabolism, pharmacokinetics and plasma protein binding were investigated. Results: The elimination half-life (t1/2) values in rats after a single intravenous dose of 3, 15 and 75 mg/kg were estimated as 43.53±10.82, 22.86±4.23, and 21.17±8.64 min, and the values of the area under the plasma concentration-time curve (AUC0→∞) were 329.34±144.07, 974.79±177.27, and 5251.49±786.98 mg•min/L, respectively. The plasma protein binding rate in rats was determined as about 65% by equilibrium dialysis after 72 hr. After 24 hr of intravenous administration, 16.30%, 3.47% and 9.72% of the given dose were excreted in urine, feces and bile, respectively. The metabolites of the vitexin were hydrolyzed via deglycosylation. The pharmacokinetics of dogs after intravenous administration revealed t1/2, AUC0-∞ and mean residence time (MRT0-∞) values of 20.43±6.37 min, 227.96±26.68 mg•min/L and 17.12±4.33 min, respectively. The no-observed-adverse- effect level (NOAEL) was 50 mg/kg body weight/day. There was no significant accumulation effect at 8 or 20 mg/kg/day in dogs over 92 days of repeated administration. For the 50 mg/kg/- day dose group, the exposure (AUC, Cmax) decreased significantly with prolonged administration. This trend suggests that repeated administration accelerates vitexin metabolism. Conclusion: The absorption of vitexin following routine oral administration was very low. To improve the bioavailability of vitexin, the development of an injectable formulation would be a suitable alternative choice.

Purpose: For users with severe motor impairments such as high paraplegia, constructing a simplified, practical, and effective brain-computer interface (BCI) system is critical to improve the quality of life and reduce nursing requirements. This is challenging for users who retain only muscle function above the neck. Method: In this experiment, both able-bodied and motor impairment subjects attended to a flickering stimulus and performed jaw clenches simultaneously. This paper focused on the feasibility of sharing the same collection sites for steady-state visual evoked potentials (SSVEPs) with electromyograms (EMGs) and the potential of building a parallel hybrid BCI system. Results: The results reveal that when the visual stimulation frequency was lower than 20 Hz, there was no serious crosstalk between SSVEP and EMG from jaw clench actions. The EMG signal slightly affects the recognition of SSVEP, while the recognition rate of jaw clench movements based on the mixed signal exceeded 95%. Conclusions: For patients with severe disabilities, the rare applicable EMG signal is facial muscle electrical activity. The proposed study made full use of the combination of jaw clench-related EMG and SSVEP to solve this problem. Only using the same occipital electrodes to simultaneously collect SSVEP with jaw clench-related EMG and classify them could further promote the development and practical application of hybrid BCIs.

To construct a high-performance next-generation carbon-based flexible supercapacitor, high porosity, large mass density, and high flexibility are three significant challenging goals. However, one side always affects another. Herein, high-density tetratomic-doped porous composite carbon derived from sustainable biomaterials is achieved via two-step processes of carbonization and acid-washing treatment. The assembled carbon-based electrodes are highly doped with various heteroatoms (B, O, N, and P) for 33.59 atom %, resulting in abundant porosity, high densities, high pseudocapacitive contribution for 84.5%, and superior volumetric capacitive performance. The fabricated flexible electrode exhibits high flexibility, high mass loading (316 mg cm–3), and remarkable tensile strength (44.6 MPa). Generally, the volumetric performance is key and a significant parameter to appraise the electrochemical characteristics of flexible supercapacitors within a limited space. The aqueous symmetric supercapacitor demonstrates a high volumetric energy density and an excellent power density of 2.08 mWh cm–3and 498.4 mW cm–3, respectively, along with 99.6% capacitance retention after 20 000 cycles, making it competitive to even some pseudocapacitors.

Waste biomass material derived carbon has become an important energy storage material which is easily available, inexpensive and environmentally friendly. However, it is a major challenge to develop ultra-high specific capacity and stable anode materials based on biomass carbon materials (BCMs). In this work, saponin pod skin was doped with thiourea through a simple hydrothermal process, followed by being sintered in one step to obtain simultaneously N and S elements co-doped porous carbon anode material for sodium ion batteries (SIBs). The active sites and layer spacing of the original pure BCM have been altered, which are conducive to the promotion of ion/electron transport. The half battery (Na/electrolyte/C) has a specific capacity of 259 mAh g‐−1at 0.1 A g−1maintaining a specific capacitance of 238 mAh g−1after 250 cycles, meanwhile it could reach a potential capacity of 239 mAh g−1at 1.0 A g−1which maintaining a specific capacity of 120 mAh g−1after 1000 cycles. This research provides new strategy for the development of novel biomass-derived carbon materials as anode materials for high-performance SIBs.

Interfacial solar steam generation (ISSG) has recently received much attention as a low-carbon-footprint and high-energy-efficient strategy for seawater desalination and wastewater treatment. However, achieving the goals of a high evaporation rate, ecofriendliness, and high tolerance to salt ions in brine remains a bottleneck. Herein, a novel hydrogel-based evaporator for effective solar desalination was synthesized on the basis of sodium alginate (SA) and carboxymethyl chitosan (CMCS) incorporating a carbon nanotube (CNT)-wrapped melamine sponge (MS) through a simple dipping–drying–cross-linking process. The hydrogel-based evaporator reaches a high evaporation rate of 2.18 kg m–2h–1in 3.5 wt % brine under 1 sun irradiation. Furthermore, it demonstrated excellent salt ion rejection in high-concentration salt water. Simultaneously, it exhibits excellent purification functionality toward heavy metals and organic dyes. This study provides a simple and efficient strategy for seawater desalination and wastewater treatment.

The low power consumption of RLCDs has significant advantages over traditional display solutions, making it a competitive candidate for next‐generation green displays. However, in some cases, improper design may cause the RLCD to turn yellowish, causing display distortion. To solve this, we proposed a series of methods to solve such color cast problems. In this paper, the reflectance associated with the phase state between the circular polarizer and the liquid crystal has been adjusted by liquid crystal to decrease this color cast. By redesigning the liquid crystal parameters, the color deviation has been successfully improved. Finally, the samples produced on production lines verified that the Improvement Scheme did make the yellowish panel whiter.

This report discusses a potential reflected color filter for colorful display device. In this design, diffraction gratings could be color filter, reflect specific wavelengths to present blue, green, and red, even cyan and yellow. A 120nm silicon layer lays on a quartz substrate, and the silicon layer was patterned to generate a two‐dimensional circular pillars with different geometric parameters from 180nm pitch to 350nm Meanwhile, it has good tolerance to pillars shape and lattice parameters which are friendly news for volume production. Last but not least, these structures are independence of the polarization and insensitive angular of the incident light of 30°. These RGBCY five primary colors will extend the color gamma to 143% of NTSC. Designed structures can be volume fabricated by nano‐imprint lithography and etching processes.

In quantum dot color filter (QDCF) LCD blue backlight is converted to red/green light separately by red/green quantum dot materials. In cell polarizer is necessary due to the depolarization of quantum dot material. WGP is more promising as in cell polarizer. Therefore it is particularly important to insure the transmittance of blue light as high as possible. In the article, the stacks of WGP and the upper and lower layers were designed to improve the transmittance of blue light. WGP with the upper and lower layers by chemical vapor deposition was fabricated by using nano‐imprinting lithography. The blue light transmittance of WGP in the panel without the upper and lower layers was about 24%. We optimized the design of thin film without changing the structure of WGP to make the transmittance to be increased to 40%. Experimental results showed that the proposed design could achieve a fairly high transmittance 39%.

In quantum dot color filter (QDCF) LCD blue backlight is converted to red/green light separately by red/green quantum dot materials. In cell polarizer is necessary due to the depolarization of quantum dot material. WGP is more promising as in cell polarizer. Therefore it is particularly important to insure the transmittance of blue light as high as possible. In the article, the stacks of WGP and the upper and lower layers were designed to improve the transmittance of blue light. WGP with the upper and lower layers by chemical vapor deposition was fabricated by using nano‐imprinting lithography. The blue light transmittance of WGP in the panel without the upper and lower layers was about 24%. We optimized the design of thin film without changing the structure of WGP to make the transmittance to be increased to 40%. Experimental results showed that the proposed design could achieve a fairly high transmittance 39%.

Flexible energy-storage devices based on supercapacitors rely largely on the scrupulous design of flexible electrodes with both good electrochemical performance and high mechanical properties. Here, nitrogen-doped carbon nanofiber networks/reduced graphene oxide/bacterial cellulose (N-CNFs/RGO/BC) freestanding paper is first designed as a high-performance, mechanically tough, and bendable electrode for a supercapacitor. The BC is exploited as both a supporting substrate for a large mass loading of 8 mg cm–2and a biomass precursor for N-CNFs by pyrolysis. The one-step carbonization treatment not only fabricates the nitrogen-doped three-dimensional (3D) nanostructured carbon composite materials but also forms the reduction of the GO sheets at the same time. The fabricated paper electrode exhibits an ultrahigh areal capacitance of 2106 mF cm–2(263 F g–1) in a KOH electrolyte and 2544 mF cm–2(318 F g–1) in a H2SO4electrolyte, exceptional cycling stability (∼100% retention after 20000 cycles), and excellent tensile strength (40.7 MPa). The symmetric supercapacitor shows a high areal capacitance (810 mF cm–2in KOH and 920 mF cm–2in H2SO4) and thus delivers a high energy density (0.11 mWh cm–2in KOH and 0.29 mWh cm–2in H2SO4) and a maximum power density (27 mW cm–2in KOH and 37.5 mW cm–2in H2SO4). This work shows that the new procedure is a powerful and promising way to design flexible and freestanding supercapacitor electrodes.

Space flight has been shown to induce bone loss and muscle atrophy, which could initiate the degeneration of articular cartilage. Countermeasures to prevent bone loss and muscle atrophy have been explored, but few spaceflight or ground-based studies have focused on the effects on cartilage degeneration. In this study, we investigated the effects of exercise on articular cartilage deterioration in tail-suspended rats. Thirty-two female Sprague-Dawley rats were randomly divided into four groups (n=8in each): tail suspension (TS), tail suspension plus passive motion (TSP), tail suspension plus active exercise (TSA), and control (CON) groups. In the TS, TSP, and TSA groups, the rat hindlimbs were unloaded for 21 days by tail suspension. Next, the cartilage thickness and volume, and the attenuation coefficient of the distal femur were evaluated by micro-computed tomography (μCT). Histological analysis was used to assess the surface integrity of the cartilage, cartilage thickness, and chondrocytes. The results showed that: (1) the cartilage thickness on the distal femur was significantly lower in the TS and TSP groups compared with the CON and TSA groups; (2) the cartilage volume in the TS group was significantly lower compared with the CON, TSA, and TSP groups; and (3) histomorphology showed that the chondrocytes formed clusters where the degree of matrix staining was lower in the TS and TSP groups. There were no significant differences between any of these parameters in the CON and TSA groups. The cartilage thickness measurements obtained by μCT and histomorphology correlated well. In general, tail suspension could induce articular cartilage degeneration, but active exercise was effective in preventing this degeneration in tail-suspended rats.

The purpose of this study was to explore the triphasic mechanical properties of osteoarthritic cartilage with different pathological grades. First, samples of cartilage from rabbits with different stages of osteoarthritis (OA) were graded. Following this, the cartilage was strained by a swelling experiment, and changes were measured using a high-frequency ultrasound system. The result, together with fixed charge density and water volume fraction of cartilage samples, was used to estimate the uniaxial modulus of the cartilage tissue, based on a triphasic model. For the control cartilage samples, the uniaxial elastic modulus on the cartilage surface was lower than those in the middle and deep layers. With an increase in the OA grade, the uniaxial elastic modulus of the surface, middle and deep layers decreased. A significant difference was found in the surface elastic modulus of different OA grades (P<0.01), while no significant differences were identified for OA cartilages of Grades 1 and 2 in the middle and deep layers (P<0.01). Compared with Grades 1 and 2, there was a significant reduction in the elastic modulus in the middle and deep layers of Grade 3 OA cartilage (P<0.05). Overall, this study may provide a new quantitative method to evaluate the severity of OA using the mechanical properties of cartilage tissue.

Subtle changes of articular cartilage (AC) can lead to tissue degeneration and even osteoarthritis (OA). The early degeneration of AC is closely related to a change in proteoglycans (PG) content. The observation of PG is therefore an appropriate way of studying OA and evaluating the degree of AC degeneration. In this study, 20 cartilage-bone samples were prepared from normal porcine femoral condyle cartilage and 10 samples were digested over 2 h using 0.25% trypsin solution. The dynamic process of PG-digestion was explored using a conventional A-mode ultrasound (US) experimental system with a 10 MHz center frequency. Quantitative acoustic parameters were calculated from ultrasonic radio-frequency echo signals and included US speed (USS), US amplitude attenuation coefficient (UAA) and broadband US attenuation coefficient (BUA). The experimental results showed that the conventional A-mode ultrasound is valuable for tracking the degree of PG-digestion. Histology also confirmed the validity of the ultrasound observations. For every AC sample, the degree of PG-digestion within a given time was different and was affected by individual differences. After two hours of degeneration, USS showed a mean decrease of 0.4% (P<0.05). UAA was significantly lower after a two-hour PG depletion period (from (2.45±0.23) to (2.28±0.41) dB mm−1). BUA showed no significant differences during this process. In conclusion, conventional ultrasound can provide useful information about trypsin-induced progressive PG depletion in AC and can reflect variations of PG content via the quantitative acoustic parameters USS and UAA. The results of this study may be used to identify an indirect indicator of cartilage matrix integrity and OA disease progression.

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Three novel perylene polyimides (PPIs) containing p‐n diblock units were designed and synthesized for use in dye‐sensitized mesoporous TiO2solar cells. They all dissolve in m‐cresol and N‐methyl‐2‐pyrrolidone (NMP). Their visible light absorption, electrochemical and photoelectrochemical properties were systematically studied. The polyimides have band gap energies of 2.16, 2.19 and 2.25 eV deduced from ultraviolet–visible absorption spectra, and electron affinity (Ea) and ionization potential (IP) of −3.93 and 6.10 eV for PPI1, −3.94 and 6.13 eV for PPI2, −3.93 and 6.59 eV for PPI3, respectively, deduced from cyclic voltammogram. Experimental data show that introduction of 4,4′‐bisaminetriphenylamine cannot only greatly enhance optic‐electro conversion efficiency, but also enhance the dissolubility which in favorable for making the devices. The relationship of structure and properties of PPI is discussed and the mechanism of photocurrent generation is explained. Copyright © 2004 John Wiley & Sons, Ltd.

Anisotropy was induced in poly‐Schiff bases containing triphenylamine with linearly polarized light at 488 nm. Both writing and relaxation processes were described with a biexponential function. The alignment process involved two response modes: a fast response mode and a slow one. The fast response mode was associated with angular‐dependent trans–cis photoisomerization, whereas the slow one was attributed to the position adjustment of the rigid main chains used to obtain well‐aligned monodomains. The writing rate increased with an increase in the light intensity at a low intensity of the irradiation light. Structural factors such as main‐chain rigidity seemed to play important roles in the remaining stored information. The two polymers had large photoinduced birefringence values (0.01 and 0.0015, respectively). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2274–2279, 2004

The primary purpose of this study was to investigate the aerodynamic characteristics of laryngectomees under two conditions: breathing quietly and speaking with electrolarynx. Twenty male adult subjects, 8 normal speakers, and 12 laryngectomees participated the experiment. Airflow, pressure, and speech data were obtained simultaneously. The acceptability of electrolarynx speech under different conditions was also evaluated by 20 listeners (14 men, 6 women). Results indicated a higher peak expiration airflow and pressure among the laryngectomees as compared with the normal during breathing. Three different breathing patterns appeared among the laryngectomees when speaking with the electrolarynx: holding breath, exhaling, and breathing. Four long-time electrolarynx users held breath during speaking. Seven of 12 laryngectomees kept exhaling, whereas only 1 could breathe during speech production. In addition, (1) the acceptability of electrolarynx speech was the highest when speaking breathlessly; (2) no significant difference was found in the acceptability between the patterns of exhaling and breathing smoothly; and (3) the acceptability decreased if breathing quickly during phonation with the electrolarynx. It also suggests that the laryngectomees who can breathe during speaking may be more appropriate to use the new electrolarynx controlling the pitch by expiration pressure.

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