Two-dimensional van der Waals thin film transistors as active matrix for spatially resolved pressure sensing

The development of pressure sensor arrays capable of distinguishing the shape and texture details of objects is of considerable interest in the emerging fields of smart robots,prostheses,human-machine interfaces,and artificial intelligence(AI).Here we report an integrated pressure sensor array,by combining solution-processed two-dimensional(2D)MoS2 van der Waals(vdW)thin film transistor(TFT)active matrix and conductive micropyramidal pressure-sensitive rubber(PSR)electrodes made of polydimethylsiloxane/carbon nanotube composites,to achieve spatially revolved pressure mapping with excellent contrast and low power consumption.We demonstrate a 10×10 active matrix by using the 2D MoS2 vdW-TFTs with high on-off ratio>10^(6),minimal hysteresis,and excellent device-to-device uniformity.The combination of the vdW-TFT active matrix with the highly uniform micropyramidal PSR electrodes creates an integrated pressure sensing array for spatially resolved pressure mapping.This study demonstrates that the solution-processed 2D vdW-TFTs offer a solution for active-matrix control of pressure sensor arrays,and could be extended for other active-matrix arrays of electronic or optoelectronic devices.

Cryptotanshinone attenuates isoprenaline-induced cardiac fibrosis in the mouse associated with upregulation and activation of matrix metalloproteinase-2

Objectives The impairment of matrix metallopro- teinase-2(MMP-2)has been associated with the development of cardiac fibrosis.Although the Chinese herb Salvia miltior-rhiza has been widely used in patients with cardiovascular disorders,the mechanisms involved have not been elucidated. The purpose of the present study was to determine whether the administration of cryptotanshinone,an active ingredient of Salvia miltiorrhiza,could prevent the cardiac fibrosis induced by isoprenaline and to investigate the underlying mechanisms. Methods and Results Male C57BL/6 mice were submitted to receive daily injection of 0.9%saline,3 mg/kg isoprenaline, or isoprenaline plus 20 mg/kg cryptotanshinone by gastric gavage for 2 weeks.Herein,we demonstrate that cryptotanshinone can significantly ameliorate the isoprenaline-induced cardiac fibrosis,which was associated with marked up-regulation and activation of MMP-2 in ventricular myocardium. Additionally,we demonstrate that cryptotanshinone can dose-dependently upregulate and activate MMP-2 in cultured cardiac fibroblast.Moreover,incubation with cryptotanshinone also can prevent isoprenaline-induced downregulation and inactivation of MMP-2 in cultured cardiac fibroblast. Conclusions Taken together,our data suggest that cryptotanshinone may become a novel and potent antifibrotic agent. The present findings might further our understanding of the role of MMP-2 in cardiac fibrosis and antifibrotic mechanisms of cryptotanshinone.

Rosiglitazone uppresses lipopolysaccharide-induced matrix metalloproteinase-2 activity in rat aortic endothelial cells via rasMEK1/2 signaling

ix metalloproteinase(MMPs) plays a key role in the pathogenesis of chronic inflammatory disease,such as atherosclerosis.Among MMPs,MMP-2 is regarded as a major proteinase in atherosclerotic plaque lesions.Peroxisome proliferator activated receptor-gamma(PPARg) ameliorates oxidative stress and the inflammatory response.The aim of the present study was to evaluate the effect of Rosiglitazone on Lipopolysaccharide(LPS)-induced MMP-2 activation as well as its possible mechanism.LPS-induced MMP-2 activity was inhibited by Rosiglitazone(PPARg agonist) in the rat aortic endothelial cells(RAEC).LPS-induced MMP-2 activation was diminished no matter exposure to NF-kB Activation Inhibitor II(JSH-23)or Ras inhibitor,farnesylthiosalicylic acid(FTS). Further study shows that LPS-induced activation of Phospho-Rho A and Phospho-MEKl/2 were significantly inhibited by Rosiglitazone.The activation of NF-kB p65 in the nuclear extract of cells was also significantly suppressed by Rosiglitazone, moreover,the expression of NF-κB p65 was partly activated by GW9662(PPARg antagonist).NF-kB DNA binding activity was also demolished by Rosiglitazone.In summary,our data showed that PPARg agonist,Rosiglitazone suppresses LPS-activated MMP-2 secretion via Ras-MEK1/2 signaling pathways and NF-kB activation.PPARg agonist and Ras-MEK1/2 pathway may be another potential therapeutic target for the disease induced by chronic inflammation.

Advances in mobility enhancement of ITZO thin-film transistors:a review

Indium-tin-zinc oxide(ITZO)thin-film transistor(TFT)technology holds promise for achieving high mobility and offers significant opportunities for commercialization.This paper provides a review of progress made in improving the mobility of ITZO TFTs.This paper begins by describing the development and current status of metal-oxide TFTs,and then goes on to explain the advantages of selecting ITZO as the TFT channel layer.The evaluation criteria for TFTs are subsequently introduced,and the reasons and significance of enhancing mobility are clarified.This paper then explores the development of high-mobility ITZO TFTs from five perspectives:active layer optimization,gate dielectric optimization,electrode optimization,interface optimization,and device structure optimization.Finally,a summary and outlook of the research field are presented.

Design on AM-OLED display control ASIC with high gray scale levels

The paper puts forward a method on controlling the AM-OLED panel to display image with high gray scale levels. It also gives an ASIC design sample to implement this method. A twenty sub-fields scan scheme has been taken into use in the chip to display 256 gray scale levels on a QVGA resolution AM-OLED display screen. The functions of image scaling and rotating have also been implemented for multiply application. The simulation and chip test result show that the chip design has met the design requirements.

Heuristic algorithm for RCPSP with the objective of minimizing activities' cost

Resource-constrained project scheduling problem（RCPSP） is an important problem in research on project management. But there has been little attention paid to the objective of minimizing activities＇ cost with the resource constraints that is a critical sub-problem in partner selection of construction supply chain management because the capacities of the renewable resources supplied by the partners will effect on the project scheduling. Its mathematic model is presented firstly, and analysis on the characteristic of the problem shows that the objective function is non-regular and the problem is NP-complete following which the basic idea for solution is clarified. Based on a definition of preposing activity cost matrix, a heuristic algorithm is brought forward. Analyses on the complexity of the heuristics and the result of numerical studies show that the heuristic algorithm is feasible and relatively effective.

Microstructure and Mechanical Performance of Cu-SnO_2-rGO based Composites Prepared by Plasma Activated Sintering

A novel chemical technique combined with unique plasma activated sintering（PAS） was utilized to prepare consolidated copper matrix composites（CMCs） by adding Cu-SnO2-rGO layered micro powders as reinforced fillers into Cu matrix. The repeating Cu-SnO2-rGO structure was composed of inner dispersed reduced graphene oxide（r GO）, SnO2 as intermedia and outer Cu coating. SnO2 was introduced to the surface of rGO sheets in order to prevent the graphene aggregation with SnO2 serving as spacer and to provide enough active sites for subsequent Cu deposition. This process can guarantee rGO sheets to suffi ciently disperse and Cu nanoparticles to tightly and uniformly anchor on each layer of rGO by means of the SnO2 active sites as well as strictly control the reduction speed of Cu^2＋. The complete cover of Cu nanoparticles on rGO sheets thoroughly avoids direct contact among rGO layers. Hence, the repeating structure can simultaneously solve the wettability problem between rGO and Cu matrix as well as improve the bonding strength between rGO and Cu matrix at the well-bonded Cu-SnO2-rGO interface. The isolated rGO can effectively hinder the glide of dislocation at Cu-rGO interface and support the applied loads. Finally, the compressive strength of CMCs was enhanced when the strengthening effi ciency reached up to 41.

On the Extent of Environmental Health

Background: Main purpose of this article is to offer information, criteria and conceptual proposals that could clarify the extent or scope of environmental health, and systematize the approaches for its institutional stewardship by environmental health services. Hopefully, it will be useful to managers, professionals, technicians and academics involved in the management, implementation, teaching or research of this multidisciplinary field. Methods: The notion of “environment” is examined, a definition is proposed, and a look is taken at the “green” and “blue” sides of environmental problems. A number of understandings in various countries for “environmental health” are put forth and lists of basic areas for environmental health are analyzed. Results: One finding is that all lists are, in reality, unsystematic groupings of three different constituents: determinants, processes and functions. Consideration of these groupings leads to a homogeneous list of 18 areas and 77 sub-areas. Sets or series are provided for each type of constituent (64 determinants, 18 processes and 25 functions), and their aggregation forms the enormous universe of environmental health activities. On the other hand, certain rules of operation are proposed which make it possible, through a form of algebra, to construct expressions based on the provided sets of constituents. And it becomes possible to employ a common symbolic language for describing or assigning activities in the environmental health services. Conclusions: The article analyses the contemporaneous extent of environmental health.

N-carboxymethyl chitosan/sodium alginate composite hydrogel loading plasmid DNA as a promising gene activated matrix for in-situ burn wound treatment

Improving the degree of vascularization through the regulation of wound microenvironment is crucial for wound repair.Gene activated matrix(GAM)technology provides a new approach for skin regeneration.It is a local gene delivery system that can not only maintain a moist environment,but also increase the concentration of local active factors.For this purpose,we fabricated the mVEGF165/TGF-β1 gene-loaded N-carboxymethyl chitosan/sodium alginate hydrogel and studied its effect on promoting deep second degree burn wound repair.The average diameter of the hydrogel pores was 100μm and the porosity was calculated as 50.9%.SEM and CLSM images showed that the hydrogel was suitable for cell adhesion and growth.The NS-GAM could maintain continuous expression for at least 9 days in vitro,showing long-term gene release and expression effect.Deep second-degree burn wound model was made on the backs of Wistar rats to evaluate the healing effect.The wounds were healed by day 22 in NS-GAM group with the prolonged high expression of VEGF and TGF-β1 protein.A high degree of neovascularization and high expression level of CD34 were observed in NS-GAM group in 21 days.The histological results showed that NS-GAM had good tissue safety and could effectively promote epithelialization and collagen regeneration.These results indicated that the NS-GAM could be applied as a promising local gene delivery system for the repair of deep second-degree burn wounds.

Mixed Matrix Membranes of Polysulfone/Polyimide Reinforced with Modified Zeolite Based Filler: Preparation, Properties and Application

In this work, polysulfone/polyimide（PSf/PI） mixed matrix membranes were fabricated by reinforcement of modified zeolite（MZ） particles through solution casting method for investigation of antibacterial activity against two gram negative bacteria（Salmonella typhi, Klebsella pneumonia） and two gram positive bacteria（Staphylococcus aureus, Bacillus subtilis）. The modified zeolite particles were incorporated to PSf and PI matrix and the influence of these particles on thermal, mechanical and structural properties was evaluated. The morphological evolution was investigated through scanning electron microscopy（SEM） and transmission electron microscopy（TEM） analysis, which revealed good compatibility between organic polymer matrix and inorganic filler. Mechanical stability was investigated by tensile testing while thermal analysis was evaluated by thermogravimetric analysis（TGA） and differential scanning calorimetry（DSC）. This revealed improvement in thermal properties with increasing filler concentration from 1 wt% to 10 wt%. Structural analysis was successfully done using X-ray diffraction analysis（XRD） and Fourier transform infrared（FTIR） spectroscopy. Solvent content of fabricated mixed matrix membranes was observed to decrease while moving from more hydrophilic to less hydrophilic solvent. However, addition of filler content enhanced the porosity of fabricated membranes. The synthesized mixed matrix membranes exhibited good antibacterial activity and the highest activity was shown by PSf/PI/MZ mixed matrix membrane. Therefore, the combination effect of PSf, PI and MZ sufficiently enhanced the antibacterial activity of mixed matrix membranes.

Osteogenic potential of the human bone morphogenetic protein 2 gene activated nanobone putty

Background Nanobone putty is an injectable and bioresorbable bone substitute. The neutral-pH putty resembles hard bone tissue, does not contain polymers or plasticizers, and is self-setting and nearly isothermic, properties which are helpful for the adhesion, proliferation, and function of bone cells. The aim of this study was to investigate the osteogenic potential of human bone morphogenetic protein 2 （hBMP2） gene activated nanobone putty in inducing ectopic bone formation, and the effects of the hBMP2 gene activated nanobone putty on repairing bone defects. Methods Twenty four Kunming mice were randomly divided into two groups. The nanobone putty ＋ hBMP2 plasmid was injected into the right thigh muscle pouches of the mice （experiment side）. The nanobone putty ＋ blank plasmid or nanobone putty was injected into the left thigh muscle pouches of the group 1 （control side 1） or group 2 （control side 2）, respectively. The effects of ectopic bone formation were evaluated by radiography, histology, and molecular biology analysis at 2 and 4 weeks after operation. Bilateral 15 mm radial defects were made in forty-eight rabbits. These rabbits were randomly divided into three groups： Group A, nanobone putty ＋ hBMP2 plasmid; Group B, putty ＋ blank plasmid; Group C, nanobone putty only. Six rabbits with left radial defects served as blank controls. The effect of bone repairing was evaluated by radiography, histology, molecular biology, and biomechanical analysis at 4, 8, and 12 weeks after operation. Results The tissue from the experimental side of the mice expressed hBMP2. Obvious cartilage and island-distributed immature bone formation in implants of the experiment side were observed at 2 weeks after operation, and massive mature bone observed at 4 weeks. No bone formation was observed in the control side of the mice. The ALP activity in the experiment side of the mice was higher than that in the control side. The tissue of Group A rabbits expressed hBMP2 protein and higher ALP level. The new bone formation rate and antibending strength of group A was significantly higher than those of group B and C. The defects in blank control were not healed. Conclusions The hBMP2 gene activated nanobone putty exhibited osteoinductive ability, and had a better bone defect repair capabilitv than that of nanobone putty only.

Tissue engineering in mandibular reconstruction: osteogenesis-inducing scaffolds

Currently, the gold standard for aesthetic and functional reconstruction of critical mandibular defects is an autologous fibular flap;however, this carries risk of donor site morbidity, and is not a promising option in patients with depleted donor sites due to previous surgeries. Tissue engineering presents a potential solution in the design of a biomimetic scaffold that must be osteoconductive, osteoinductive, and support osseointegration. These osteogenesis-inducing scaffolds are most successful when they mimic and interact with the surrounding native macro- and micro-environment of the mandible. This is accomplished via the regeneration triad: (1) a biomimetic, bioactive osteointegrative scaffold, most likely a resorbable composite of collagen or a synthetic polymer with collagen-like properties combined with beta-tri calcium phosphate that is 3D printed according to defect morphology;(2) growth factor, most frequently bone morphogenic protein 2 (BMP-2);and (3) stem cells, most commonly bone marrow mesenchymal stem cells. Novel techniques for scaffold modification include the use of nano-hydroxyapatite, or combining a vector with a biomaterial to create a gene activated matrix that produces proteins of interest (typically BMP-2) to support osteogenesis. Here, we review the current literature in tissue engineering in order to discuss the success of varying use and combinations of scaffolding materials (i.e., ceramics, biological polymers, and synthetic polymers) with stem cells and growth factors, and will examine their success in vitro and in vivo to induce and guide osteogenesis in mandibular defects.