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In this paper, the electrospinning technique has been employed to fabricate PVDF/CuO/Al nanocomposites, where the formulation was optimized on the basis of maximizing the reaction heat with increased efficiency. The graphene oxide (GO) has also been used as both lubricant and catalyst, which is well dispersed inside the PVDF matrix by the electrospinning process as well. It has been found that the smooth PVDF nano-fibers could be fabricated with GO content of 0.5 wt%, where the Al and CuO nanoparticles are also uniformly loaded. In comparison with the n-CuO/n-Al and PVDF/CuO/Al prepared by conventional mechanical mixing method, the GO-doped PVDF/CuO/Al nanocomposites via electrospinning improved heat of reaction, density as well as anti-oxidation capability. In addition, the electrospinning technique and doping of 0.5 wt% of GO can improve the reaction efficiency of PVDF/CuO/Al nanocomposites since they contribute to dispersion of components and homogeneous structure fabrication.

This study investigated the damage and failure mechanism of composite laminates under low-velocity impact and compression-after-impact (CAI) loading conditions by numerical and experimental methods. Ultrasonic C-scan, DIC and SEM methods were combined to give a new and deep insight of damage evolution and failure mechanisms in composite laminates. A novel three-dimensional damage model based on continuum damage mechanics was developed to investigate the impact and CAI behavior with consideration of both interlaminar delamination damage and intralaminar damage. The maximum-strain failure criterion and an improved three-dimensional Puck criterion, which was physically-based, were employed to capture the initiation of fiber and matrix damage respectively and a bi-linear damage constitutive relation was used for characterization of damage evolution. The interlaminar delamination damage was simulated by the interfacial cohesive behavior. Good correlation between numerical and experimental results demonstrated the effectiveness and rationality of the proposed numerical model. The effects of impact energy level and multiple impacts were discussed.

In order to enhance the heat release of nanoparticles silicon, the Si@AP/NC metastable intermixed composites (MICs) Si@AP/NC with varied content of silicon (40%, 60%, and 80%) were designed and prepared by electrospray. Observation by scanning electron microscopy (SEM) has shown that the morphological characterization of those composites was homogeneously mixed. The thermal properties of those MICs were evaluated by means of DSC-TG techniques. Results show that the low- and high-temperature decomposition of AP transitioned from two separated stages to a one-step process. This was mainly caused by the interaction of thin silica on the surface of silicon and perchloric acid. The dependence of activation energy on the conversation rate was obtained by making use of state-of-the-art kinetic procedures. It has been found that decomposition of Si@NC/AP-40 and Si@NC/AP-60 followed the random chain scission model. With the strengthening of active centers of silica, the mechanism of proton migration of AP turned into the growth of the nucleus. The decomposition process of AP started on the surface of the crystal and gradually decomposed steadily as AP decomposition proceeded. Therefore, it is a first-order reaction model for Si@NC/AP-60 and Si@NC/AP-80 in their second-step reaction. Overall, manufacture spherical Si-NPs composites wrapped in polymer though electrostatic spray technology, a novel way of preparing nanoenergetic materials was created. These nanocomposites could be applied normally as fuels in thermobaric explosives or solid propellants.

The graphene oxide (GO) was found to be able to stabilize organic molecules including energetic compounds. However, the inherent mechanisms of such stabilization effects are still not well-known. Herein, various transition metal complexes of triaminoguanidine nitrate (TAGN) using GO as a dopant have been prepared and evaluated. It has been shown that the presence of GO could great improve the thermal stability of the resulted TAG-based complexes. The physical models governing their thermolysis for their initial rate-limiting decomposition steps are obtained using the state-of-the-art evaluation methods. These physical models are further supported by analyses of the overall gaseous products. In addition, the reaction pathways are proposed to explain the stabilization mechanisms of GO. For instance, by interaction of GO, the release of N2 from TAG-Ni was greatly postponed. There is a broad secondary peak at temperature of 378 °C due to decomposition of the nickel nitrides, as the primary thermolysis intermediates of TAG-Ni. The formation of cobalt nitrides plays a significant role on decomposition of TAG-Co and G-T-Co, which results in much less heat release and mass loss in comparison to TAG-Ni.

The addition of graphene-based energetic catalysts to the solid propellants may improve the combustion efficiency, and meantime maintain its energy level and high thermal stability, which are of great importance for the solid propellant applications. Various new energetic coordination polymers (ECPs), based on the graphene oxide (GO) copper(II) complex, have been synthesized using 5,5′-bis-tetrazole (H2BT) or 5,5-bis-tetrazole-1,1-dioldehydrate (DHBT) as the ligands, by hydrothermal and solvothermal methods. It has been shown that crystal structure and morphologies could be changed by regulation of the synthetic methods, resulting in a series of the graphene-based bis-tetrazole complexes using the same starting materials. The graphene-based energetic azole-based ECPs showed higher thermostability than the pristine metal complexes due to stabilization effect of graphene, and change in crystal forms also makes thermostability different. The heat releases from AP have been increased by three to four times under the catalytic effects of these GO-based ECPs, where two exothermic peaks of AP merged into one at 290.5 °C for GO-Cu-DBT/AP and 316.2 °C for GO-Cu-BT/AP. A shoulder peak is shown after the main exothermic peak of RDX due to the post-effect of the catalysts on its condensed products with secondary reactions.

Among deep learning methods, convolutional neural networks (CNNs) are able to extract features automatically and have increasingly been used in intelligent fault diagnosis studies. However, studies seldomly concentrate on the weakness associated with a highly imbalanced distribution of fault types due to different failure rates and when multiple faults are easily confused with single faults. To solve these problems, this paper developed a stochastic discrete-time series deep convolutional neural network (SDCNN) method based on random oversampling along with a progressive method with multiple SDCNNs to improve the diagnosis performance. To assess the developed method, datasets from three avionics 24-pulse auto-transformer rectifier units (ATRUs), which are secondary electric power supplies in aircraft, were analyzed and compared with other CNN methods.

An earthquake is a natural disaster with great destructive power and serious harm to humans. The collection of earthquake disaster information is a very complicated task, and it is even more difficult to mine valuable information from the massive, scattered and real-time changing disaster data. In response to the problems of slow and fragmented postearthquake disaster acquisition, large errors in disaster assessment, and inadequate decision support, this paper describes the design of open data interfaces to collect disaster data information from different sources and different structures in the shortest time, then implement integrated encoding to achieve dynamic management of disaster data throughout the life cycle. The experiment shows that the effect is good. This result provides a decision-making basis for rapid and effective emergency rescue of relevant departments.

A robust monoclonal antibody (mAb) bioprocess requires physiological parameters such as temperature, pH, or dissolved oxygen (DO) to be well-controlled as even small variations in them could potentially impact the final product quality. For instance, pH substantially affects N-glycosylation, protein aggregation and charge variant profiles, as well as mAb productivity. However, relatively less is known about how pH jointly influences product quality and titer. In this study, we investigated the effect of pH on culture performance, product titer and quality profiles by applying longitudinal multi-omics profiling, including transcriptomics, proteomics, metabolomics and glycomics, at three different culture pH set points. The subsequent systematic analysis of multi-omics data showed that pH set points differentially regulated various intracellular pathways including intracellular vesicular trafficking, cell cycle, and apoptosis, thereby resulting in differences in specific productivity, product titer and quality profiles. In addition, a time-dependent variation in mAb N-glycosylation profiles, independent of pH was identified to be mainly due to the accumulation of mAb proteins in the endoplasmic reticulum (ER) over culture time, disrupting cellular homeostasis. Overall, this multi-omics-based study provides an in-depth understanding of the intracellular processes in mAb-producing CHO cell line under varied pH conditions and could serve as a baseline for enabling the quality optimization and control of mAb production.

Background CIMP (CpG island methylator phenotype) is an epigenetic molecular subtype, observed in multiple malignancies and associated with the epigenetic silencing of tumor suppressors. Currently, for most cancers including gastric cancer (GC), mechanisms underlying CIMP remain poorly understood. We sought to discover molecular contributors to CIMP in GC, by performing global DNA methylation, gene expression, and proteomics profiling across 14 gastric cell lines, followed by similar integrative analysis in 50 GC cell lines and 467 primary GCs. Results We identify the cystathionine beta-synthase enzyme (CBS) as a highly recurrent target of epigenetic silencing in CIMP GC. Likewise, we show that CBS epimutations are significantly associated with CIMP in various other cancers, occurring even in premalignant gastroesophageal conditions and longitudinally linked to clinical persistence. Of note, CRISPR deletion of CBS in normal gastric epithelial cells induces widespread DNA methylation changes that overlap with primary GC CIMP patterns. Reflecting its metabolic role as a gatekeeper interlinking the methionine and homocysteine cycles, CBS loss in vitro also causes reductions in the anti-inflammatory gasotransmitter hydrogen sulfide (H2S), with concomitant increase in NF-κB activity. In a murine genetic model of CBS deficiency, preliminary data indicate upregulated immune-mediated transcriptional signatures in the stomach. Conclusions Our results implicate CBS as a bi-faceted modifier of aberrant DNA methylation and inflammation in GC and highlights H2S donors as a potential new therapy for CBS-silenced lesions.

Chloroplast genomes are widely used in genetic engineering, molecular marker development, and phylogeny. In order to analyze the complete chloroplast genome of Dianthus caryophyllus, the complete chloroplast genome of D. caryophyllus was sequenced and annotated. On the other hand, phylogenetic analysis of the chloroplast genome of D. caryophyllus was carried out. The results showed that the whole length of the chloroplast genome of D. caryophyllus was 147,604 bp, and had a typical conserved quadripartite structure. The G and C basic content of D. caryophyllus chloroplast was 36.3%. The genome contained 83 protein-coding genes, 34 tRNA genes, and 6 rRNA genes. Among the protein-coding genes, 10 genes contain a single intron and 2 genes contain two introns. The phylogeny of D. caryophyllus indicated that the closest phylogenetic relationship was D. longicalyxanus. This study provides materials for the molecular study of D. caryophyllus may improve the carnation industry.

Walnut is a popular nut tree species and usually suffers from drought stress. However, little information is available on the mechanism of walnut responding to drought stress, resulting in lack of basic understanding for its resistance. In order to excavate more functional genes that can respond to stressors, and enrich the theoretical basis for walnut resistance, in this study, 5 MYB genes with complete ORFs were identified from J. regia and the basic bio-information as well as expression patterns in different tissues and response to drought and ABA stresses were confirmed using qRT-PCR assay. The results showed that 2 JrMYB genes belong to R1-MYB subfamily and 3 JrMYBs belong to R2R3-MYB, encoding the proteins from 212 to 362 aa in length. The phylogenetic analysis categorized proteins of 5 JrMYBs and 40 Arabidopsis AtMYBs into 10 subgroups. JrMYBs in the same subgroup exhibited significant similarities in the composition of conserved domains and motifs in amino acid sequences and exon/intron organization in DNA sequences. The results of qRT-PCR analysis revealed that JrMYB genes diversely expressed in various tissues. Moreover, the expression values of JrMYBs were upregulated or downregulated significantly under drought and ABA stresses. Most attractively, in contrast with suffering from drought stress alone, the treatments with drought and additional ABA greatly enhanced the transcript levels of JrMYBs. All these results suggested that JrMYB genes play a vital role in plant biological processes and drought as well as ABA stress response, and possibly perform as ABA-dependent drought response transcription factors in plant. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12298-021-01008-z.

The cocrystallization method that combines various constituents into cocrystals yields the newly formed materials with significantly enhanced charge transport properties. However, this strategy has not been greatly utilized in all-conjugated block copolymers (BCPs). Herein, we scrutinize the relationship between cocrystals and charge mobilities in all-conjugated BCPs (i.e., poly(3-butylthiophene)-block-poly(3-hexylthiophene); denoted P3BT-b-P3HT) by tuning their molecular weights and thermal annealing process. All the rod-rod BCPs form cocrystals with high charge mobilities than P3BT and P3HT homopolymers and P3BT/P3HT blend, imparting the cocrystal-facilitated charge transport because of the synergy of two conjugated components. Upon 150 °C treatment, their crystallinities increase and their charge mobilities at 15k, 18k, and 28k increase slightly. In contrast, P3BT-b-P3HT-12k shows decreased charge mobilities. It is due to the preferential increase of crystal size and order through the π-π stacking direction in the former while through the alkyl stacking direction in the latter. Intriguingly, when these P3BT-b-P3HT cocrystals experience two-step thermal treatment, P3BT-b-P3HT-12k retains its cocrystalline structure, while microphase separation of P3BT and P3HT occurs in P3BT-b-P3HT-15k, 18k, and 28k with different degrees. All P3BT-b-P3HT BCPs exhibit decreased charge mobilities. This study demonstrates the cocrystallization-promoted charge mobility in all-conjugated BCPs, which may facilitate their application in a wide range of optoelectronic devices.

A visible-light-promoted S-H insertion reaction between thiols and α-diazoesters was developed. The reaction proceeded smoothly at room temperature with a broad substrate scope, affording various thioethers in moderate to excellent yields. The catalyst- and additive-free nature, sustainable energy source and mild reaction conditions make this strategy more eco-friendly.

This paper collects data on the damage to the traffic system caused by earthquakes in China in the past two decades, and uses KNN algorithm, SVM algorithm, logistic regression algorithm, naive Bayes algorithm and decision tree algorithm to train the data, then establish earthquake prediction models. The paper introduces the process of preprocessing, modelling, evaluation, and visualization of disaster data. An earthquake disaster inversion model based on traffic data has been established, which can predict the earthquake intensity based on the relevant data provided by the traffic department. The prediction accuracy is relatively accurate, which is very helpful for earthquake prediction and rescue operations.

Background. This study is aimed at investigating the repairing effect of mesenchymal stem cells and their exosomes from different sources on ovarian granulosa cells damaged by chemotherapy drugs—phosphoramide mustard (PM). Methods. In this study, we choose bone marrow mesenchymal stem cells (BMSCs) and human placental mesenchymal stem cells (HPMSCs) for research. Then, they were cocultured with human ovarian granulosa cells (SVOG) injured by phosphoramide mustard (PM), respectively. β-Galactosidase staining, flow cytometry, and Western blot were used to detect the changes in the senescence and apoptosis of SVOG cells before and after their coculture with the above two types of MSCs. Subsequently, exosomes from these two types of MSCs were extracted and added to the culture medium of SVOG cells after PM injury to test whether these two types of exosomes played a role similar to that of MSCs in repairing damaged SVOG cells. Results. PM treatment-induced apoptotic SVOG cells were significantly decreased after HPMSCs and BMSCs as compared with control group. After coculturing with these two types of MSCs, PM-treated SVOG cells showed significantly reduced senescence and apoptosis proportions as well as cleaved-Caspase 3 expression, and HPMSCs played a slightly stronger role than BMSCs in repairing SVOG cells in terms of the above three indicators. In addition, the ratios of senescent and apoptotic SVOG cells were also significantly reduced by the two types of exosomes, which played a role similar to that of MSCs in repairing cell damages. Conclusions. The results indicated that BMSCs, HPMSCs, and their exosomes all exerted a certain repair effect on SVOG cells damaged by PM, and consistent repair effect was observed between exosomes and MSCs. The repair effect of exosomes secreted from BMSCs and HPMSCs on the SVOG cells was studied for the first time, and the results fully demonstrated that exosomes are the key carriers for MSCs to play their role.

The evaluation index system of computer network operation and maintenance management is a yardstick to measure the quality of network operation and maintenance services. It plays an important guiding role in the construction of the network operation and maintenance management system. A scientific and accurate comprehensive evaluation index system must be established to ensure the objectivity and fairness of the evaluation. This paper first summarizes the basic connotation of decentralized and centralized network operation and maintenance management modes, and then makes a comparative analysis of the two operation and maintenance modes using a combination of qualitative analysis and quantitative analysis, to verify the effectiveness and superiority of the centralized operation and maintenance management mode, thereby exploring the evaluation method of computer network operation quality.

Matlab is a powerful mathematical simulation software, which is widely used in many scientific fields such as theoretical analysis, engineering design, etc. In this paper, a Matlab program was written, and used to set up a poor lubrication model of piston ring pack. In this simulation model, the effect of surface roughness between cylinder-piston ring pack was considered, and an improved piston ring condition was used. Besides, this Matlab program was applied to diesel PA6-280 piston ring pack. At last, the minimum oil film thickness distribution curve was obtained within a working cycle of each ring.

The precise mechanism through which macroautophagy/autophagy affects psoriasis is poorly understood. Here, we found that keratinocyte (KC) autophagy, which was positively correlated with psoriatic severity in patients and mouse models and could be inhibited by mitogen-activated protein kinase (MAPK) family inactivation. The impairment of autophagic flux alleviated psoriasisform inflammation. We also found that an autophagy-based unconventional secretory pathway (autosecretion) dependent on ATG5 (autophagy related 5) and GORASP2 (golgi reassembly stacking protein 2) promoted psoriasiform KC inflammation. Moreover, the alarmin HMGB1 (high mobility group box 1) was more effective than other autosecretory proteins in regulating psoriasiform cutaneous inflammation. HMGB1 neutralization in autophagy-efficient KCs eliminated the differences in psoriasiform inflammation between Krt14(+/+)-Atg5(f/f) KCs and Krt14(Cre/+)-atg5(f/f) KCs, and conversely, recombinant HMGB1 almost completely restored psoriasiform inflammation in Krt14(Cre/+)-atg5(f/f) KCs in vivo. These results suggest that HMGB1-associated autosecretion plays a pivotal role in cutaneous inflammation. Finally, we demonstrated that Krt14(Cre/+)-hmgb1(f/f) mice displayed attenuated psoriatic inflammation due to the essential crosstalk between KC-specific HMGB1-associated autosecretion and γδT cells. Thus, this study uncovered a novel autophagy mechanism in psoriasis pathogenesis, and the findings imply the clinical significance of investigating and treating psoriasis. Abbreviations: 3-MA: 3-methyladenine; ACTB: actin beta; AGER: advanced glycosylation end-product specific receptor; Anti-HMGB1: anti-HMGB1 neutralizing antibody; Anti-IL18: anti-IL18 neutralizing antibody; Anti-IL1B: anti-IL1B neutralizing antibody; ATG5: autophagy related 5; BAF: bafilomycin A(1); BECN1: beclin 1; CASP1: caspase 1; CCL: C-C motif chemokine ligand; CsA: cyclosporine A; ctrl shRNA: lentivirus harboring shRNA against control; CXCL: C-X-C motif chemokine ligand; DCs: dendritic cells; DMEM: dulbecco’s modified Eagle’s medium; ELISA: enzyme-linked immunosorbent assay; EM: electron microscopy; FBS: fetal bovine serum; GORASP2 shRNA: lentivirus harboring shRNA against GORASP2; GORASP2/GRASP55: golgi reassembly stacking protein 2; GR1: a composite epitope between LY6 (lymphocyte antigen 6 complex) locus C1 and LY6 locus G6D antigens; H&E: hematoxylin and eosin; HMGB1: high mobility group box 1; HMGB1 shRNA: lentivirus harboring shRNA against HMGB1; IFNG/IFN-γ: interferon gamma; IL17A: interleukin 17A; IL18: interleukin 18; IL1A/IL-1α: interleukin 1 alpha; IL1B/IL-1β: interleukin 1 beta; IL22/IL-22: interleukin 22; IL23A: interleukin 23 subunit alpha; IL23R: interleukin 23 receptor; IMQ: imiquimod; ITGAM/CD11B: integrin subunit alpha M; ITGAX/CD11C: integrin subunit alpha X; IVL: involucrin; KC: keratinocyte; KD: knockdown; KO: knockout; Krt14(+/+)-Atg5(f/f) mice: mice bearing an Atg5 flox allele, in which exon 3 of the Atg5 gene is flanked by two loxP sites; Krt14(+/+)-Hmgb1(f/f): mice bearing an Hmgb1 flox allele, in which exon 2 to 4 of the Hmgb1 gene is flanked by two loxP sites; Krt14(Cre/+)-atg5(f/f) mice: keratinocyte-specific atg5 knockout mice generated by mating Atg5-floxed mice with mice expressing Cre recombinase under the control of the promoter of Krt4; Krt14(Cre/+)-hmgb1(f/f) mice: keratinocyte-specific hmgb1 knockout mice generated by mating Hmgb1-floxed mice with mice expressing Cre recombinase under the control of the promoter of Krt14; Krt14-Vegfa mice: mice expressing 164-amino acid Vegfa splice variant recombinase under the control of promoter of Krt14; LAMP1: lysosomal associated membrane protein 1; LDH: lactate dehydrogenase; LORICRIN: loricrin cornified envelope precursor protein; M5: TNF, IL1A, IL17A, IL22 and OSM in combination; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MAPK: mitogen-activated protein kinase; MKI67: marker of proliferation Ki-67; MTT: thiazolyl blue tetrazolium bromide; NFKB/NF-κB: nuclear factor kappa B; NHEKs: primary normal human epidermal keratinocytes; NS: not significant; OSM: oncostatin M; PASI: psoriasis area and severity index; PtdIns3K: class III phosphatidylinositol 3-kinase; qRT-PCR: quantitative RT-PCR; RELA/p65: RELA proto-oncogene, NF-kB subunit; rHMGB1: recombinant HMGB1; rIL18: recombinant interleukin 18; rIL1B: recombinant interleukin 1 beta; S100A: S100 calcium binding protein A; SQSTM1/p62: sequestosome 1; T17: IL17A-producing T; TCR: T-cell receptor; tcrd KO mice: tcrd (T cell receptor delta chain) knockout mice, which show deficient receptor expression in all adult lymphoid and epithelial organs; TLR: toll-like receptor; TNF/TNF-α: tumor necrosis factor; WOR: wortmannin; WT: wild-type; γδT17 cells: IL17A-producing γδ T cells.

Several transition metal complexes of triaminoguanidine (TAG) nitrate, TAG-Ni, TAG-Co, graphene oxide (GO)/TAG-Ni (GT-Ni), GO/TAG-Co (GT-Co), and GO/ TAG-Cu (GT-Cu) were prepared using GO as a stabilizer. It has been shown that these complexes are promising energetic catalysts for decomposition of ammonium perchlorate (AP), which was uniformly coated with the mentioned catalysts. The decomposition kinetic parameters and mechanisms of the complexes have been studied by means of differential scanning calorimetry/thermogravimetric techniques. Results show that the presence of GO in such hybrid catalysts is able to stabilize AP before its decomposition, but the strong catalytic effects occur on HClO4 as the intermediate of the initial decomposition of AP. In the cases of TAG-Co, GT-Co, and GT-Cu, they would make the two-step decomposition of AP into a single step. The heat releases have been greatly increased as well because of a more complete decomposition. More importantly, the thermolysis mechanism of AP c...

Using methanol as a sustainable C1 source, cobalt-catalyzed α-methoxymethylation and α-aminomethylation of ketones have been developed. With cheap CoCl2·6H2O as catalyst and TBHP as oxidant, the methoxymethylated products were obtained within a short reaction time in up to 91% yield. Based on the observed reversibility of methoxy adduct to enone, the α-aminomethylation of ketones was then achieved by a one-pot methylenation/aza-Michael addition sequence. In addition, an easy way to convert α-methoxymethyl ketones to α-aminomethyl ketones has been discovered.

In this paper, the graphene oxide (GO) doped transition metal (Cu, Co, and Ni) complexes of triaminoguanidine (TAG) have been prepared where the GO serves as the stabilizing agent. The catalytic reactivity of GO stabilized TAG-M (M = Cu, Co, Ni) energetic composites on thermolysis of 1,3,5-trinitro-1,3,5-triazinane (RDX) has been investigated by using DSC/TGA techniques. It has been found that these materials have strong catalytic effects on decomposition of RDX by decreasing the apparent activation energy. Meantime, GO would not only stabilize TAG-M energetic composites but also enhance the thermal stability of RDX due to its high thermal conductivity. The physical models that govern the decomposition processes were also studied, and it has been shown that different reaction processes are accomplished by varying transition metals or in cooperation with GO. The complex catalyst, with improved thermal stability, represents a unique class of catalyst of considerable value for catalytic combustion and safety...

Advances in mobile networks and low-power electronics have driven smart mobile medical devices at a tremendous pace, evoking increased interest in household healthcare, especially for those with cardiovascular or respiratory disease. Thus, flexible battery-free pressure sensors, with great potential for monitoring respiration and heartbeat in a smart way, are urgently demanded. However, traditional flexible battery-free pressure sensors for subtle physiological signal detecting are mostly tightly adhered onto the skin instead of working under the pressure of body weight in a noncontact mode, as the low sensitivity in the high-pressure region can hardly meet the demands. Moreover, a hollow microstructure (HM) with higher deformation than solid microstructures and great potential for improving the pressure sensitivity of self-powered sensors has never been investigated. Here, for the first time, we demonstrated a noncontact heartbeat and respiration monitoring system based on a flexible HM-enhanced self-powered pressure sensor, which possesses the advantages of low cost, a high dynamic-pressure sensitivity of 18.98 V·kPa

Flexible pressure sensors have attracted increasing attention for wide application in wearable electronics and artificial intelligence. To enhance the pressure sensitivity of such sensors, a theoretical study based on modeling and experimental validation is required. Here, we theoretically demonstrated a method for optimizing the sensitivity of flexible piezoelectret-based pressure sensors (FPPS) by investigating the electric-mechanical behavior. A new model was established to estimate the compressibility and analyze the pressure sensitivity of the tunable FPPS. Experimental verification was carried out by fabrication of an FPPS based on a perfluoro (alkoxy alkane) (PFA) electret and tuning of the supporting structures. Based on tuning of the pressure sensitivity of the FPPS, a pressure sensor with a sensitivity of 15 V kPa−1 in the range of 0–2.5 kPa was demonstrated and successfully applied for energy harvesting and self-powered human biological signal detection.

This paper aims to investigate the impact of board characteristics and auditors on the disclosure practices of listed companies in the Philippines. This study used a self-constructed research instrument, namely the ASEAN Disclosure Index, to assess the extent of corporate disclosure of 21 the Philippines’ listed companies from 2011-2015, made out of 105 observations. The index covers 212 information items, with three attributes: financial information (76 items), non-financial information (68 items) and strategic information (68 items). An empirical result reports that the result reveals that an audit committee independence is positively significant at 95% level while board size and a number of board meetings held in the year are negatively significant at 95% level. For other variables covering board independence, a number director participation rates, gender diversity, CEO duality, a number of audit committee meetings, a number of audit committee participation rates and quality of external auditors, no significant relationship was found. This study contributes to the literature by offering a new instrument for assessing the extent of corporate disclosure in Southeast Asia region and also providing a novel viewpoint into the relationships between corporate governance mechanisms on information disclosure practices in a context of developing countries like the Philippines. Definitely, the contributed empirical evidence of this study might also help regulators for enhancing the level of corporate disclosure in the Philippines as well as neighboring countries in Southeast Asia region.

Visible light, in combination with the molecular iodine catalyst-mediated α-hydroxylation of α-methylene ketones, has been developed. The reaction proceeds smoothly in methanol at room temperature under aerobic conditions and shows exclusive selectivity toward methylene ketones. Mechanistic studies have revealed that the reaction proceeds by a radical pathway. Renewable energy, metal-free catalyst and abundant oxygen source alongside a wide scope and novel selectivity are features that make this strategy practical and eco-friendly.

We propose a hybrid gap plasmonic traveling wave amplifier (TWA) with electrically pumped multiple quantum wells (MQW). This TWA has deep sub-wavelength mode field scale and works at 1310 nm window. For the polarization-independent amplification we design the InGaAlAs tensile-strain MQW. Furthermore we analyze this plasmonic TWA’s optical, electrical and thermal characteristics by finite element method. First we get the suitable trade-off point between the affordable mode propagation loss and moderate mode field size by adjusting the gap width and height. Second we find that the narrower the MQW, the higher the MQW local gain. Third, our device has good thermal performance as the plasmonic wave power is less than 5 μw. Simulation results suggest that the independent polarization gain appears at 1317 nm wavelength. At this wavelength 3.60 cm −1 mode gain and 161 nm mode width are obtained as the 9.39 kA cm−2 injection current and 10 nm × 240 nm gap size.

Piezoelectric polymers hold physical properties, such as high mechanical flexibility and smaller acoustical impedance, that piezoelectric ceramics do not have. Nevertheless, owing to the piezoelectricity originates from the crystalline region, it is still a challenge for most semi-crystalline polymers to generate a high piezoelectric response. Here, we develop a class of piezoelectret with sandwiched polymer structure (electret/dielectric/electret, EDE) which is assembled via simple electrostatic interaction. The transparent and mechanical robust EDE piezoelectrets exhibit the piezoelectric constant (d33) up to ~930 pC N-1, and the corresponding physical model is established to investigate major influence factors to the piezoelectric properties, including the relative permittivity and elastic modulus of the electret and dielectric, and the simulated results are in accord with the experimental data. We demonstrate the strain sensors and acoustic transducers based on the ultrathin and flexible EDE piezoelectret, verifying the feasibility of the electrostatic assembled piezoelectrets in the applications of epidermal and implantable electronics. Moreover, various combinations of polymers in the EDE structure can be employed based on our proposed model to explore other unique applications such as transient electronics.

Cardiovascular diseases account for the highest mortality globally, but recent advances in wearable technologies may potentially change how these illnesses are diagnosed and managed. In particular, continuous monitoring of cardiovascular vital signs for early intervention is highly desired. To this end, flexible wearable sensors that can be comfortably worn over long durations are gaining significant attention. In this review, advanced flexible wearable sensors for monitoring cardiovascular vital signals are outlined and discussed. Specifically, the functional materials, configurations, mechanisms, and recent advances of these flexible sensors for heart rate, blood pressure, blood oxygen saturation, and blood glucose monitoring are highlighted. Different mechanisms in bioelectric, mechano-electric, optoelectric, and ultrasonic wearable sensors are presented to monitor cardiovascular vital signs from different body locations. Present challenges, possible strategies, and future directions of these wearable sensors are also discussed. With rapid development, these flexible wearable sensors will potentially be applicable for both medical diagnosis and daily healthcare use in tackling cardiovascular diseases.

A novel pH fluorescence probe (PIF), derived from phenanthro[9,10-d]imidazole bound to the fluorescein, is designed and synthesized based on the intramolecular hydrogen bond and then its spectra properties are investigated. Probe PIF exhibits negligible fluorescence intensity at acidic pH condition due to ESIPT quenching caused by the formation of the intramolecular hydrogen bonds, and a significant fluorescence enhancement in neutral and weak alkaline environments because of the strengthened ICT process arose from the fracture of the intramolecular hydrogen bonds. The studies of UV–Vis and fluorescence spectra mean that probe PIF is able to respond linearly and reversibly over pH from 6.5 to 9.0 with pK a of 7.0. Moreover, the pH responses of probe PIF are stable and not disturbed by the common cations and anions. The possible response mechanism has been proposed according to the analysis of 1H NMR and DFT calculations.

Horn antenna is one of the simplest even widely used antennas in the RF and microwave regimes. However, few systematic investigations on pyramidal horn antennas are found at optical frequency while optical antennas are extensively studied in various applications. Here, we investigate the feature of pyramidal horn nanoantennas and explore the mechanism of nanofocusing. Although the dimensions of antenna can be optimized through numerical simulations for the applications, it is inefficient due to the large degree of freedom of a horn antenna. Firstly, we analyze both the scattering loss and the dissipative loss during compressing electromagnetic waves in the horn antennas while the dimensions gradually decrease. Then, we establish an analytic and simple approach of mode matching, which is based on the effective index method, to efficiently squeeze light into arbitrarily small 3D nanospots. We numerically demonstrate that a nanofocusing spot of πλ 2/1200 at the wavelength of 785 nm with 1.2 dB losses is achieved by a pyramidal horn nanoantenna with the analytically determined dimensions. The intensity enhancement is further increased to more than 6000 times by introducing surface plasmon coupling at the input interface.

Wearable healthcare devices with monitoring, treating and protecting applications can provide reliable and newfangled interactive service for people. Herein, a bi-functional smart face mask based on electrospun polyetherimide (PEI) electret nonwoven is developed. By virtue of the surplus charges maintained steadily in the PEI nonwoven, the smart face mask possesses bi-functions of removing the particulate matter and generating electricity. Moreover, the unique applications for dynamically monitoring the particulate matter removal ability and human's respiratory rates are demonstrated. Besides offering an unique air filter, this study will promisingly promote the progress of self-powered wearable electronics.

The shadow banking system has grown stronger in the process of evading supervision. Together with traditional commercial banks, it has become an important participant in the financial system, which has caused a fundamental change in the structure of the global financial system. As an exogenous reform force in China’s special period, Shadow Bank has become an important channel for financial resources to “disconnect from reality”. Despite the lack of substantial securitization, China’s shadow banking system has developed rapidly. This paper analyzes the development motivation.This paper believes that the scope of China’s shadow banking system can be defined according to the nature of the fund supply side.

Aiming at the problem of oversubscription of data relay access request of user stars in future Space-Based Information System, the problem of resource scheduling optimization for data relay satellite system with microwave and laser hybrid links is studied. The characteristics of the hybrid links are analyzed. A multi-objective programming model on static resource scheduling constraint satisfaction problem is established, and a hybrid optimization algorithm integration of artificial immune strategies, niche ideas and improved genetic algorithm is put forward to solve the scheduling model. Simulation results show that the hybrid optimization algorithm optimizes the model quickly, and performs well in the ability of global optimization and convergence. The results validate that the static resource scheduling model could accurately describe the microwave and laser hybrid links relay satellite system resource scheduling problem with multi-tasking and multi-type antenna1.

Polytetrafluoroethylene (PTFE) is a fascinating electret material widely used for energy harvesting and sensing, and an enhancement in the performance could be expected by reducing its size into nanoscale because of a higher surface charge density attained. Hence, the present study demonstrates the use of nanofibrous PTFE for high-performance self-powered wearable sensors. The nanofibrous PTFE is fabricated by electrospinning with a suspension of PTFE particles in dilute polyethylene oxide (PEO) aqueous solution, followed by a thermal treatment at 350 °C to remove the PEO component from the electrospun PTFE-PEO nanofibers. The obtained PTFE nanofibrous membrane exhibits good air permeability with pressure drop comparable to face masks, excellent mechanical property with tensile strength of 3.8 MPa, and stable surface potential of − 270 V. By simply sandwiching the PTFE nanofibrous membrane into two pieces of conducting carbon clothes, a breathable, flexible, and high-performance nanogenerator (NG) device with a peak power of 56.25 μW is constructed. Remarkably, this NG device can be directly used as a wearable self-powered sensor for detecting body motion and physiological signals. Small elbow joint bending of 30°, the rhythm of respiration, and typical cardiac cycle are clearly recorded by the output waveform of the NG device. This study demonstrates the use of electrospun PTFE nanofibrous membrane for the construction of high-performance self-powered wearable sensors. Electronic supplementary material The online version of this article (10.1186/s11671-019-3091-y) contains supplementary material, which is available to authorized users.

Camellia oleiferais one of the four largest woody edible oil plants in the world with high ecological and medicinal values. Due to frequent interspecific hybridization, it was difficult to study its genetics and evolutionary history. This study usedC. oleiferathat was collected on Hainan Island to conduct our research. The unique island environment makes the quality of tea oil higher than that of other species grown in the mainland. Moreover, a long-term geographic isolation might affect gene structure. In order to better understand the molecular biology of this species, protect excellent germplasm resources, and promote the population genetics and phylogenetic studies ofCamelliaplants, high-throughput sequencing technology was used to obtain the chloroplast genome sequence of HainanC. oleifera. The results showed that the whole chloroplast genome ofC. oleiferain Hainan was 156,995 bp in length, with a typical quadripartite structure of a large single copy (LSC) region of 86,648 bp, a small single copy (SSC) region of 18,297 bp, and a pair of inverted repeats (IRs) of 26,025 bp. The whole genome encoded a total of 141 genes (115 different genes), including 88 protein-coding genes, 45 tRNA genes, and eight rRNA genes. Among these genes, nine genes contained one intron, two genes contained two introns, and four overlapping genes were also detected. The total GC content of HainanC. oleifera’s chloroplast genome was 37.29%. The chloroplast genome structure characteristics of HainanC. oleiferawere compared with mainlandC. oleiferaand those of the other eight closely related Theaceae species; it was found that the contractions and expansions of the IR/LSC and IR/SSC regions affected the length of chloroplast genome. The chloroplast genome sequences of these Theaceae species were highly similar. A comparative analysis indicated that the Theaceae species were conserved in structure and evolution. A total of 51 simple sequence repeat (SSR) loci were detected in the chloroplast genome of HainanC. oleifera, and allCamelliaplants did not have pentanucleotide repeats, which could be used as a good marker in phylogenetic studies. We also detected seven long repeats, the base composition of all repeats was biased toward A/T, which was consistent with the codon bias. It was found that HainanC. oleiferahad a similar evolutionary relationship withC. crapnelliana, through the use of codons and phylogenetic analysis. This study can provide an effective genomic resource for the evolutionary history of Theaceae family.

A quantitative evaluation method has been developed to study the effects of nanoadditives on thermal decomposition mechanisms of energetic compounds using the conventional thermogravimetry coupled with mass spectrometry (TG/MS) technique. The decomposition of ammonium perchlorate (AP) under the effect of several energetic catalysts has been investigated as a demonstration. In particular, these catalysts are transition metal (Cu2+, Co2+ and Ni2+) complexes of triaminoguanidine (TAG), using graphene oxide (GO) as dopant. They have been well-compared in terms of their catalytic effects on the concentration of the released gaseous products of AP. These detailed quantitative analyses of the gaseous products of AP provide a proof that the proton transfer between ∙O and O2 determines the catalytic decomposition pathways, which largely depend on the type of reactive centers of the catalysts. This quantitative method could be applied to evaluate the catalytic effects of any other additives on the thermal decomposition of various energetic compounds.

At present, the network architecture is based on the TCP/IP protocol and node communications are achieved by the IP address and identifier of the node. The IP address in the network remains basically unchanged, so it is more likely to be attacked by network intruder. To this end, it is important to make periodic dynamic hopping in a specific address space possible, so that an intruder fails to obtain the internal network address and grid topological structure in real time and to continue to perform infiltration by the building of a new address space layout randomization system on the basis of SDN from the perspective of an attacker.

With the continuous development of optical communication technology, the structure of optical network is becoming more and more complex, and complex network theory can analyze the nature of the actual system. From the angle of self-organizing criticality, the “sand pile” model of intelligent optical network is constructed, the model parameters are designed, and the self-organized critical model of intelligent optical network is established. Finally, the computer algorithm is designed according to the model, and the critical value of the whole network load is solved. The research shows that there is a quantitative relationship between the critical value of network load and the number of the betweenness, which has a certain guiding significance for improving the processing ability of key nodes and optimizing the network security.

Figure S1. a. SEM images and b. XRD pattern of the PTFE-PEO nanofibrous membrane. Figure S2. a. SEM image and b. pressure drop as a function of gas flow rate of the conducting carbon cloth. Figure S3. a. Output of the NG device with different pressing forces at a frequency of 5â Hz. b. Output of the NG device at different frequencies with a pressing force of 5â N. (PDF 561 kb)

IMPORTANCE Exfoliation syndrome is a systemic disorder characterized by progressive accumulation of abnormal fibrillar protein aggregates manifesting clinically in the anterior chamber of the eye. This disorder is the most commonly known cause of glaucoma and a major cause of irreversible blindness. OBJECTIVE To determine if exfoliation syndrome is associated with rare, protein-changing variants predicted to impair protein function. DESIGN, SETTING, AND PARTICIPANTS A 2-stage, case-control, whole-exome sequencing association study with a discovery cohort and 2 independently ascertained validation cohorts. Study participants from 14 countries were enrolled between February 1999 and December 2019. The date of last clinical follow-up was December 2019. Affected individuals had exfoliation material on anterior segment structures of at least 1 eye as visualized by slit lamp examination. Unaffected individuals had no signs of exfoliation syndrome. EXPOSURES Rare, coding-sequence genetic variants predicted to be damaging by bioinformatic algorithms trained to recognize alterations that impair protein function. MAIN OUTCOMES AND MEASURES The primary outcome was the presence of exfoliation syndrome. Exome-wide significance for detected variants was defined as P < 2.5 x 10(-6). The secondary outcomes included biochemical enzymatic assays and gene expression analyses. RESULTS The discovery cohort included 4028 participants with exfoliation syndrome (median age, 78 years [interquartile range, 73-83 years]; 2377 [59.0%] women) and 5638 participants without exfoliation syndrome (median age, 72 years [interquartile range, 65-78 years]; 3159 [56.0%] women). In the discovery cohort, persons with exfoliation syndrome, compared with those without exfoliation syndrome, were significantly more likely to carry damaging CYP39A1 variants (1.3% vs 0.30%, respectively; odds ratio, 3.55 [95% CI, 2.07-6.10]; P = 6.1 x 10(-7). This outcome was validated in 2 independent cohorts. The first validation cohort included 2337 individuals with exfoliation syndrome (median age, 74 years; 1132 women; n = 1934 with demographic data) and 2813 individuals without exfoliation syndrome (median age, 72 years; 1287 women; n = 2421 with demographic data). The second validation cohort included 1663 individuals with exfoliation syndrome (median age, 75 years; 587 women; n = 1064 with demographic data) and 3962 individuals without exfoliation syndrome (median age, 74 years; 951 women; n = 1555 with demographic data). Of the individuals from both validation cohorts, 5.2% with exfoliation syndrome carried CYP39A1 damaging alleles vs 3.1% without exfoliation syndrome (odds ratio, 1.82 [95% CI, 1.47-2.26]; P < .001). Biochemical assays classified 34 of 42 damaging CYP39A1 alleles as functionally deficient (median reduction in enzymatic activity compared with wild-type CYP39A1, 94.4%[interquartile range, 78.7%-98.2%] for the 34 deficient variants). CYP39A1 transcript expression was 47% lower (95% CI, 30%-64% lower; P < .001) in ciliary body tissues from individuals with exfoliation syndrome compared with individuals without exfoliation syndrome. CONCLUSIONS AND RELEVANCE In this whole-exome sequencing case-control study, presence of exfoliation syndrome was significantly associated with carriage of functionally deficient CYP39A1 sequence variants. Further research is needed to understand the clinical implications of these findings. National Research Foundation of SingaporeNational Research Foundation, Singapore [NRF-NRFI2018-01]; US National Eye Institute of the National Institutes of Health [R01 EY020928, P30 EY014104, UM1 CA186107, U01 CA167552, EY015473]; Glaucoma Research Foundation of Canada [X052, CIRG17may053]; National Medical Research Council of SingaporeNational Medical Research Council, Singapore The study was funded by grant NRF-NRFI2018-01 from the National Research Foundation of Singapore. Additional support was provided by grants R01 EY020928, P30 EY014104, UM1 CA186107, U01 CA167552, and EY015473 from the US National Eye Institute of the National Institutes of Health, funding from the Glaucoma Research Foundation of Canada, and grants X052 and CIRG17may053 from the National Medical Research Council of Singapore.

Convolutional neural networks (CNNs) are able to extract features automatically. Fault identification and location of transformer rectifier units (TRUs) which are widely used as an avionic secondary power supply are significant for system reliability. Based on the analyzation of TRUs, this paper discusses the design process of the developed discrete time-series convolution neural network (DTCNN) and develops a hierarchical method for TRUs fault diagnosis along with a transfer learning-based fault diagnosis method instead of training new models for different TRUs. The DTCNN construction is determined firstly. Then, the performance of HDCNN is validated. On the basis, the conditions of a suitable source dataset for TRU fault diagnosis and the transfer layers from the pre-trained HDCNN are discussed. The comparison with other algorithms under different noise conditions shown that the transfer learning is an effective way to construct the diagnosis network for similar equipment and often can lead to better performance.

In this paper, the widely used energetic material RDX had been modified with 2D high nitrogen polymer (TAGP). Various hybrid RDX crystals (qy-RDX) with higher detonation velocity and better thermostability had been obtained as a result of strong intermolecular interactions between TAGP and RDX molecules. The performance of the qy-RDX had been characterized to clarify the inherent mechanisms. It shows that the⊿Hf of qy-RDX could be largely changed in the range of 23.4 kJ kg-1 to 1343.6 kJ kg-1, whereas the density varies only from 1.81 g cm-3 to 1.86 g cm-3. The resulted detonation velocities are in the range of 8725.5 m·s-1 to 9251.8 m·s-1, depending on the content and state of the TAGP dopant. The sensitivity of the resulted qy-RDX is much better than pristine RDX due to improved crystal quality as well as higher concentration of hydrogen bonds. The impact energy is improved from 8.5 J (RDX) to 22 J (qy-RDX-1), whereas the friction sensitivity improves form 130 N to over 360 N for the same case. The Ea for thermal decomposition of qy-RDX-1has reduced from 147.8 kJ mol-1 (RDX) to (124.5 kJ mol-1), since TAGP dopant could be considered as active catalytic sites after melting of RDX.

Previous studies have demonstrated that E proteins induce activation-induced deaminase (AID) expression in activated B cells. Here, we examined the role of Id3 in germinal center (GC) cells. We found that Id3 expression is high in follicular B lineage cells but declines in GC cells. Immunized mice with Id3 expression depleted displayed a block in germinal center B cell maturation, showed reduced numbers of marginal zone B cells and class-switched cells, and were associated with decreased antibody titers and lower numbers of plasma cells. In vitro, Id3-depleted B cells displayed a defect in class switch recombination. Whereas AID levels were not altered in Id3-depleted activated B cells, the expression of a subset of genes encoding signaling components of antigen receptor-, cytokine receptor-, and chemokine receptor-mediated signaling was significantly impaired. We propose that during the GC reaction, Id3 levels decline to activate the expression of genes encoding signaling components that mediate B cell receptor- and or cytokine receptor-mediated signaling to promote the differentiation of GC B cells.

Melamine (Mel) is added illegally to foods and feeds due to its high nitrogen content and high intake, and it causes serious health problems, so it is urgent to build a simple and quick method for detecting Mel in our daily life. In this work, a self-powered Mel detection method is developed that is based on the newly invented triboelectric nanogenerator (TENG) by using the strong electronegativity property of Mel. In addition, Mel can enhance the electrical output signals of the TENGs by pairing with other triboelectric materials. Thus a high-sensitive Mel sensor is designed based on polytetrafluoethylene (PTFE) TENG; the output current of TENG increases with the addition of Mel, resulting in largely improved detection limit of Mel with 0.5 ppb and a linear increase range from 1 to 500 ppb. This study not only develops a new type of material for TENG, but also demonstrates an innovative and convenient method for the detection of Mel and other biomaterials.