Characteristic Study of Self-Powered Sensors Based on Native Protein Composite Film

Flexible electronic sensors composed of flexible film and conductive materials play an increasingly important role in wearable and internet information transmission.It has received more and more attention and made some progress over the decades.However,it is still a great challenge to prepare biocompatible and highly transparent conductive films.Egg white is a pure natural protein-rich material.Hydroxypropylmethyl cellulose has a good compatibility and high transparency,which is an ideal material for flexible sensors.Here,we overcome the problem of poor mechanical flexibility and electrical conductivity of protein,and develop a high transparency and good flexibility hydroxypropylmethyl cellulose/egg white protein composite membrane-based triboelectric nanogenerator('X'-TENG).The experimental results show that the flexible pressure sensor based on'X'-TENG has a high sensitivity,fast response speed,and low detection limit.It can even be used as a touch/pressure sensing artificial electronic skin.It can also be made into an intelligent waffle keyboard for recording and tracking users of the keyboard.Our strategy may provide a new way to easily build flexible electronic sensors and move toward practical applications.

“化瘀”理论指导下运用三步理筋手法联合TDP照射治疗落枕

目的观察在中医“化瘀”理论指导下三步理筋手法联合TDP照射治疗落枕的疗效。方法选择2019年6月13日—2021年6月12日确诊为落枕的患者75例随机分成治疗组、手法对照组和TDP对照组,每组25例。在中医“化瘀”理论指导下,治疗组采用三步理筋手法联合TDP局部照射治疗,手法对照组采用三步理筋手法治疗,TDP对照组采用TDP照射,每日一次,3次一疗程。记录每次治疗结束时每组患者疼痛视觉模拟评分(VAS)、颈部左右旋转范围和一个疗程结束后临床疗效的数据,并作统计学处理。结果①治疗组第一次、第二次治疗后的VAS和一个疗程后治愈率优于手法对照组(P<0.05),而这两组的颈部旋转范围和一个疗程后愈显率无显著性差异(P>0.05);②治疗组各项指标优于TDP对照组(P<0.05);③手法对照组每次颈部活动度、第三次VAS及一个疗程后愈显率优于TDP对照组(P<0.05),而这两组第一次、第二次VAS及第一个疗程后治愈率无显著性差异(P>0.05)。结论在“化瘀”理论指导下运用三步理筋手法联合TDP治疗落枕疗效优于单纯采用三步理筋手法或者单纯TDP照射治疗。

屈光不正儿童后极部视网膜厚度及视盘周围神经纤维层厚度的观察

目的:利用频域光学相干断层扫描仪(SD-OCT)对屈光不正儿童后极部视网膜厚度及视网膜神经纤维层(retinal nerve fiber layer,RNFL)厚度进行测量,探讨年龄、屈光度与视网膜厚度之间的相关性。方法:收集2016-02/2017-02在复旦大学附属华山北院眼科门诊就诊的5～15岁屈光不正儿童96例192眼,应用SD-OCT设备对受检者视盘周围RNFL厚度和后极部视网膜厚度(posterior pole retinal thickness,PPRT),包括后极部20°范围内以视盘和黄斑连线为界,分为上方、下方、平均PPRT及距黄斑中心凹1mm视网膜厚度进行检测,并分析年龄、屈光度与PPRT及RNFL厚度的相关性。结果:SD-OCT检查示,本组病例距黄斑中心凹1mm视网膜厚度为252.72±13.87μm,平均PPRT为294.02±8.70μm,上方PPRT为294.53±9.11μm,下方PPRT为293.53±9.50μm,RNFL厚度为105.75±10.60μm。年龄与距黄斑中心凹1mm视网膜厚度呈正相关,屈光度与PPRT及RNFL厚度均呈正相关。结论:SD-OCT能够准确测量儿童后极部视网膜厚度,年龄、屈光度与视网膜厚度及RNFL厚度具有相关性。

DTI and pathological changes in a rabbit model of radiation injury to the spinal cord after ^(125)I radioactive seed implantation

Excessive radiation exposure may lead to edema of the spinal cord and deterioration of the nervous system. Magnetic resonance imaging can be used to judge and assess the extent of edema and to evaluate pathological changes and thus may be used for the evaluation of spinal cord injuries caused by radiation therapy. Radioactive ^125I seeds to irradiate 90% of the spinal cord tissue at doses of 40–100 Gy （D90） were implanted in rabbits at T10 to induce radiation injury, and we evaluated their safety for use in the spinal cord. Diffusion tensor imaging showed that with increased D90, the apparent diffusion coefficient and fractional anisotropy values were increased. Moreover, pathological damage of neurons and microvessels in the gray matter and white matter was aggravated. At 2 months after implantation, obvious pathological injury was visible in the spinal cords of each group. Magnetic resonance diffusion tensor imaging revealed the radiation injury to the spinal cord, and we quantified the degree of spinal cord injury through apparent diffusion coefficient and fractional anisotropy.

Correlation between white matter damage and gray matter lesions in multiple sclerosis patients

We observed the characteristics of white matter fibers and gray matter in multiple sclerosis patients, to identify changes in diffusion tensor imaging fractional anisotropy values following white matter fiber injury. We analyzed the correlation between fractional anisotropy values and changes in whole-brain gray matter volume. The participants included 20 patients with relapsing-remitting multiple sclerosis and 20 healthy volunteers as controls. All subjects underwent head magnetic resonance imaging and diffusion tensor imaging. Our results revealed that fractional anisotropy values decreased and gray matter volumes were reduced in the genu and splenium of corpus callosum, left anterior thalamic radiation, hippocampus, uncinate fasciculus, right corticospinal tract, bilateral cingulate gyri, and inferior longitudinal fasciculus in multiple sclerosis patients. Gray matter volumes were significantly different between the two groups in the right frontal lobe（superior frontal, middle frontal, precentral, and orbital gyri）, right parietal lobe（postcentral and inferior parietal gyri）, right temporal lobe（caudate nucleus）, right occipital lobe（middle occipital gyrus）, right insula, right parahippocampal gyrus, and left cingulate gyrus. The voxel sizes of atrophic gray matter positively correlated with fractional anisotropy values in white matter association fibers in the patient group. These findings suggest that white matter fiber bundles are extensively injured in multiple sclerosis patients. The main areas of gray matter atrophy in multiple sclerosis are the frontal lobe, parietal lobe, caudate nucleus, parahippocampal gyrus, and cingulate gyrus. Gray matter atrophy is strongly associated with white matter injury in multiple sclerosis patients, particularly with injury to association fibers.

Psychometric properties of the Caregiver Strain Questionnaire among Chinese parents of children with ADHD or ASD

Background There is an urgent need in clinical practice to measure the stress of parenting.The Caregiver Strain Questionnaire(CGSQ)was found to be useful to measure parenting stress,but it has not been validated among the Chinese population.Aims To assess the reliability and construct validity of the Chinese version of CGSQ among Chinese parents.Methods From 2016 to 2017,266 parents(patient group)with a child having DSM-5-defined attention deficit hyperactivity disorder(ADHD)(n=107)or autism spectrum disorder(ASD)(n=159)and 268 parents of healthy children(control group)were recruited to the present study in Kunming,Yunnan province.All the parents were asked to fill out the Chinese version of CGSQ.We conducted exploratory factor analysis and confirmatory factor analysis(CFA)to verify construct validity of CGSQ in both patient and control groups.Cronbach’s α coefficient as an index of internal consistency was assessed for each subscale.Fourteen days later,23 subjects filled out the scale again.Intra-class correlation coefficient was calculated to evaluate the test-retest reliability.Results(1)Cronbach’s alpha of the global scale was 0.901 for the control group and 0.952 for the patient group.The test-retest reliability for the whole scale was 0.890;(2)CFA indicated that the three-factor model had better fitting indices compared with the two-factor model in both groups.Besides,the fitting indices in the patient group were more favourable than those of the control group,withχ2/df=1.564,Goodness-of Fit Index=0.841,Comparative Fit Index=0.954,and root mean square error of approximation=0.065 for the patient group at three-factor model;(3)The caregiver strain of ASD parents was statistically higher than that of ADHD parents,and caregiver strain of ADHD parents was higher than that of control group.Conclusion These findings provide initial evidence to support the construct validity and reliability of CGSQ as a parenting stress measurement tool for Chinese parents,especially for parents of children with ADHD or ASD.

Bioprinting of Small-Diameter Blood Vessels

There has been an increasing demand for bioengineered blood vessels for utilization in both regenerative medicine and drug screening.However,the availability of a true bioengineered vascular graft remains limited.Three-dimensional(3D)bioprinting presents a potential approach for fabricating blood vessels or vascularized tissue constructs of various architectures and sizes for transplantation and regeneration.In this review,we summarize the basic biology of different blood vessels,as well as 3D bioprinting approaches and bioink designs that have been applied to fabricate vascular and vascularized tissue constructs,with a focus on small-diameter blood vessels.

A mathematical model for electrochemical chloride removal from marine cast iron artifacts

The aim of this article was to theoretically study diffusion and migration of chloride ions during electrochemical chloride removal. The proposed model would enable optimization of its application by predicting the optimal treatment time and current combination. A mathematical model for simulating the transport behavior of chloride ions was developed by consideration of diffusion and migration of chloride ions when a constant DC current density was applied through the marine cast iron artifacts. The corresponding tests were conducted to validate the mathematical model. This model predicted the data of the extraction ratio of the chloride ion that correlated satisfactorily with the experimental values. An important issue in electrochemical chloride removal was to understand how chloride ions moved, taking account of diffusion and migration of chloride ions and the release of binding chloride ions. The effects of the treatment time, externally applied current density, chloride diffusion coefficient, and rate constant of release of binding chloride ion on chloride removal are studied. The specific quantitative details applied to one-dimensional model were discussed here. This article has proposed a mathematical model for the first time, which was showed to be a useful tool that can reveal the ionic transport mechanism and optimize the application during electrochemical chloride removal.

Changes in Physiological and Biochemical Characteristics of Floral Organ Development in a Soybean Cytoplasmic-nuclear Male Sterile Line

[Objectives]This study was conducted to explore the mechanism of soybean cytoplasmic-nuclear male sterility.[Methods]With soybean cytoplasmic-nuclear male sterile line JLCMS9 A and its homotype maintainer line JLCMS9 B as experimental materials,the activity of superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT),malondialdehyde(MDA)content,starch content,soluble protein content,soluble sugar content and free proline content in flower buds,alabastrums and mature flowers were determined,and the contents and changes of auxin(IAA),gibberellin(GA3),isopentenyl adenosine(iPA)and abscisic acid(ABA)at the three stages were analyzed.[Results]The activity of SOD and CAT and the contents of MDA and free proline in the sterile line at the flower bud stage were lower than those of the maintainer line,but the opposite was true at the alabastrum stage and the flowering stage,and their values were higher than those of the maintainer line;the POD activity of the sterile line was significantly lower than that of the maintainer line at the flower bud stage,and the opposite was true at the alabastrum stage and the flowering stage,and its values were higher than those of the maintainer line;and the starch content and soluble sugar content of sterile line 9 A showed an overall upward trend,and were significantly lower than those of the maintainer line 9 B at the alabastrum stage and the flowering stage.During the whole development process of floral organs,the content of IAA in sterile line 9 A showed a trend of first increasing and then decreasing,and the content of iPA increased gradually.The contents of hormones in the sterile line were lower than those in the maintainer line.The ratios of IAA/ABA,IAA/GA3,IAA/iPA and ABA/GA3 in the sterile line were significantly different from those in the maintainer line.It is inferred that the abnormal physiological characteristics of floral organ development are related to the cytoplasmic-nuclear male sterility of soybean.The alabastrum stage may be a critical period for the occurrence of abnormal physiological and biochemical indexes in the floral organs of soybean cytoplasmic-nuclear male sterile lines.[Conclusions]This study provides a theoretical basis for the breeding of fine sterile lines of soybean and the research on the mechanism of sterility.

Biotinylated dextran amine is an ideal anterograde tracer for the corticospinal tract in a goat model of ischemic corticospinal tract injury

Existing visualized tracer studies of the corticospinal tract have been focused on rodents, which have markedly different spinal cord structures compared with humans. In this study, the segmental artery feeding the spinal cord was embolized with digital subtraction angiography to establish a goat model of ischemic spinal cord injury. Biotinylated dextran amine was injected into the motor function areas of the cortex in goats with ischemic spinal cord injury. The corticospinal tract originates from the cerebral cortex motor function area, and travels towards the lateral funiculus at the contralateral spinal dorsal horn after decussation at the pyramid. The number of corticospinal tract positive fibers was found to be gradually reduced. These findings indicate that digital subtraction angiography can be applied to a goat model of ischemic spinal cord injury. Biotinylated dextran amine visualizes the course of the goat corticospinal tract in the spinal cord, which is similar to the human spinal cord. Biotinylated dextran amine is an ideal tracer for the corticospinal tract.

Hippocampal mitochondrial cytochrome C oxidase activity and gene expression in a rat model of chronic cerebral ischemia

The present study established a rat model of chronic cerebral ischemia using bilateral common carotid artery permanent ligation to analyze cytochrome C oxidase activity and mRNA expression in hippocampal mitochondria. Results showed significantly decreased cytochrome C oxidase activity and cytochrome C oxidase II mRNA expression with prolonged ischemia time. Further analysis revealed five mitochondrial cytochrome C oxidase II gene mutations, two newly generated mutations, and four absent mutational sites at 1 month after cerebral ischemia, as well as three mitochondrial cytochrome C oxidase III gene mutations, including two newly generating mutations, and one disappeared mutational site at 1 month after cerebral ischemia. Results demonstrated that decreased cytochrome C oxidase gene expression and mutations, as well as decreased cytochrome C oxidase activity, resulting in energy dysmetabolism, which has been shown to be involved in the DatholoQical Process of ischemic brain iniurv.

PNKP Knockdown by RNA Interference Inhibits Herpes Simplex Virus-1 Replication in Astrocytes

Herpes simplex virus-1 (HSV-1) is a major pathogen that causes various central nervous system (CNS) diseases,including herpes simplex encephalitis and meningitis.According to recent studies,PNKP significantly affects the proliferation of HSV-1 in astrocytes.Here,we used viral proliferation curves to confirm the significant inhibitory effects of PNKP on HSV-1 proliferation.PNKP downregulation was also confirmed by analyzing the transcription of viral genes.We found that PNKP downregulation affects the viral DNA copy number.This study preliminarily confirms that PNKP affects viral proliferation by affecting HSV-1 genome cyclization.These results also suggest that astrocytes play a specific role in preventing HSV-1 infection.

Biological effects of EV71 infection in neural cells

Enterovirus 71 (EV71) can cause serious nervous system lesions but to date the pathogenesis has been unclear. Our results show that EV71 proliferates in the neural cells and leads to neural cell lesions. The study of the pathology of EV71 infection in neonatal rat brains shows that the invasive ability of EV71 to the nervous system in vivo may depend on many unknown factors.

The applicability of vortex identification methods for complex vortex structures in axial turbine rotor passages

The complex vortex structures in the flow around turbine rotor passages, with weak or strong, large or small vortices, interacting with each other, often generate most of aerodynamic loss in turbomachines. Therefore, it is important to identify the vortex structures accurately for the flow field analysis and the aerodynamic performance optimization for turbomachines. In this paper, by using 4 vortex identification methods (the Q criterion, the Q method, the Liutex method and the Q -Liutex method), the vortices are identified in turbine rotor passages. In terms of the threshold selection, the results show that the D method and the Q -Liutex method are more robust, by which strong and weak vortices can be visualized simultaneously over a wide range of thresholds. As for the display consistency of the vortex identification methods and the streamlines, it is shown that the Liutex method gives results coinciding best with the streamlines in identifying strong vortices, while the Q -Liutex method gives results the most consistent with the streamlines in identifying weak vortices. As to the relationship among the loss, the vortices and the shear, except for the Q criterion, the other three methods can distinguish the vortical regions from the high shear regions. And the flow losses in turbine rotor passages are often related to high shear zones, while there is a small loss within the core of the vortex. In order to obtain the variation of vortices in the turbine rotor passages at different working points, the Liutex method is applied in 2 cases of a turbine with different angles of attack. The identification results show that the strengths of the tip leakage vortex and the upper passage vortex are weaker and the distance between them is closer at a negative angle of attack. This indicates that the Liutex method is an effective method, and can be used to analyze the vortex structures and their evolution in turbine rotor passages.

All-in-one cellulose based hybrid tribo/piezoelectric nanogenerator

Aybrid tribo/piezoelectric nanogenerators (HTPENG) have been proven to be highly efficient and versatile as far as the collection and conversion of ambient energy are concerned, and the introduction of flexible and green materials is a key step for their potential applications. Here, we developed a HTPENG by using nitrocellulose nanofibril paper as the triboelectric layer and BaTiCVMWCNT@ bacterial cellulose paper as the piezoelectric layer. The output of the triboelelctric paper has considerable performance as fluorinated ethylene propylene, and the output of piezoelectric paper is more than ten times higher than the BTO/polydimethylsiloxane structure. The integrated outputs of the sandwich structured HTPENG are 18 V and 1.6 pA·cm^-2, which are capable of lighting up three LED bulbs and charging a 1 pF capacitor to 2.5 V in 80 s. In addition, the voltage signal generated by the HTPENG in contact-separation mode can be used for dynamic pressure detection. The linear range of dynamic pressure is from 0.5 to 3 N·cm^-2 with a high sensitivity of 8.276 V·cm^-2·N^-1 and a detection limit of 0.2 N·cm^-2. This work provides new insights into the design and application of cellulose-based hybrid nanogenerators with high flexibility and simple structure.

Wearable and humidity-resistant biomaterials-based triboelectric nanogenerator for high entropy energy harvesting and self-powered sensing

Triboelectric nanogenerator(TENG)provides a new solution to the energy supply by harvesting high entropy energy.However,wearable electronic devices have high requirements for flexible,humidity-resistant,and low-cost TENG.Here,environmentfriendly and multi-functional wheat starch TENG(S-TENG)was made by a simple and green method.The open-circuit voltage and short-circuit current of S-TENG are 151.4 V and 47.1μA,respectively.S-TENG can be used not only to drive and intelligently control electronic equipment,but also to effectively harvest energy from body movements and wind.In addition,the output of S-TENG was not negatively affected with the increase in environmental humidity,but increased abnormally.In the range of 20%RH–80%RH,S-TENG can be potentially used as a sensitive self-powered humidity sensor.The S-TENG paves the way for large-scale preparation of multi-functional biomaterials-based TENG,and practical application of self-powered sensing and wearable devices.

Self-powered electrochemical system by combining Fenton reaction and active chlorine geheration for organic contaminant treatment

Environmental deterioration,especially water pollution,is widely dispersed and could affect the quality of people's life at large.Though the sewage treatment plants are constructed to meet the demands of cities,distributed treatment units are still in request for the supplementary of centralized purification beyond the range of plants.Electrochemical degradation can reduce organic pollution to some degree,but it has to be powered.Triboelectric nanogenerator(TENG)is a newly-invented technology for low-frequency mechanical energy harvesting.Here,by integrating a rotary TENG(R-TENG)as electric power source with an electrochemical cell containing a modified graphite felt cathode for hydrogen peroxide(H2O2)along with hydroxyl radical(·OH)generation by Fenton reaction and a platinum sheet anode for active chlorine generation,a self-powered electrochemical system(SPECS)was constructed.Under the driven of mechanical energy or wind flow,such SPECS can efficiently degrade dyes after power management in neutral condition without any O2 aeration.This work not only provides a guideline for optimizing self-powered electrochemical reaction,but also displays a strategy based on the conversion from distributed mechanical energy to chemical energy for environmental remediation.

Hybridized triboelectric-electromagnetic nanogenerators and solar cell for energy harvesting and wireless power transmission

Energy harvesting and power transmission is a significant challenge for the self-powered technologies towards mobile electronic devices.Here,we propose a hybridized energy harvester to complement each other's strengths for simultaneously scavenging multiple types of energy and then wirelessly transmit the power.The harvester consists of electromagnetic-triboelectric nanogenerator units for collecting rotational energy and a commercial water-proof flexible solar cell.At a rotation rate of 500 rpm,the output current of electromagnetic-triboelectric nanogenerator units can reach about 630 mA through energy management.Moreover,the power harvested by hybridized energy harvester can be wirelessly transmitted up to a distance of about 100 cm in real time to charge mobile phone,anemometer,and hygrometer based on self-resonant coils.The hybridized energy harvester with wireless power transmission has potential applications in large-scale energy collection,long-distance wireless power transmission and sustainably driving mobile electronic devices.

Direct Electrochemistry of Cytochrome c at a Hierarchically Nanostructured TiO_(2) Quantum Electrode

Monodisperse TiO2 nanoparticles and urchin-like hierarchical TiO2 nanospheres assembled with ultrathin quantum nanowires(about 2 nm)have been synthesized by a simple template-free wet chemical method.The morphology,structure,and crystallinity of the TiO2 nanomaterials were investigated by field emission scanning electron microscopy(FESEM),X-ray diffraction(XRD),and high resolution transmission electron microscopy(HRTEM).Electrochemical measurements with the hierarchically nanostructured TiO2 nanospheres as an electrode showed much better reversibility for direct electrochemistry of cytochrome c(cyt c)and much higher sensitivity than for an electrode composed of the monodisperse TiO2 nanoparticles.The excellent performance of the hierarchical TiO2 nanospheres may result from a quantum size effect,and their favorable nanostructure(with the presence of an abundance of both uniform macropores and mesopores),excellent structural stability and high specific surface area.The relative ionic strength had significant effect on the direct electrochemistry.Very high ionic strengths relative to cyt c concentration(I/c)induced a conformational change of cyt c on the nanostructure-coated electrode,from the native state to a partially unfolded one in 25 mmol/L phosphate buffer solution(pH 6.8).

On the understanding of dielectric elastomer and its application for all-soft artificial heart

Although dielectric elastomer(DE)with substantial actuated strain(AS)has been reported 20 years ago,its scientific understanding remains unclear.The most accepted theory of DE,which is proposed in 2000,holds the view that AS of DE is induced by the Maxwell stress.According to this theory,materials have similar ratios of permittivity and Young’s modulus should have similar AS,while the experimental results are on contrary to this theory,and the experimental AS has no relationship with ideal AS.Here,a new dipole-conformation-actuated strain cross-scale model is proposed,which can be generally applied to explain the AS of DE without pre-strain.According to this model,several characteristics of an ideal DE are listed in this work and a new DE based on polyphosphazene(PPZ)is synthesized.The AS of PPZ can reach 84%without any pre-strain.At last,a PPZ-based all soft artificial heart(ASAH)is built,which works in the similar way with natural myocardium,indicating that this material has great application potential and possibility in the construction of an ASAH for heart failure(HF)patients.