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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.

Conjugated rod–rod block copolymers (BCPs) are important semiconducting materials because they combine the unique microphase-separation characteristics of BCPs with the remarkable optoelectronic pr...

Recently, wearable and breathable healthcare devices for air filtering and real-time vital signs monitoring have become urgently needed since virus and particulate matter (PM) cause serious health issues. Herein, we present a trap-induced dense monocharged hybrid perfluorinated electret nanofibrous membrane (HPFM) for highly efficient ultrafine PM0.3 removal with an efficiency of 99.712% under low pressure drop (38.1 Pa) and high quality factor of 0.154 Pa-1. Furthermore, a recyclable multifunctional healthcare mask is constructed by integrating the HPFM-based nanogenerator, which realizes efficient PM0.3 filtering and wireless real-time human respiration monitoring simultaneously. More importantly, the performance of this mask is still relatively stable even at 100%RH humidity and 92 °C temperature conditions for 48 h, which infers that it can be reused after disinfection. The strategy of fabricating HPFM provides an approach to obtain charge-rich stable electret materials, and the design of multifunctional masks demonstrates their potential application for future personal protection and health monitoring devices.

The fundamental relationship between microstructure, constituent, processing and performances of separating materials is really a vital issue. Traditional preparation methods for separation membranes are complex, time-consuming and easy to be fouled. Also, the durability of conventional coatings on membrane is poor. By combination of bioinspiration from mussel adhesive and fish scales’ underwater superoleophobicity, we propose a general route to prepare organic-inorganic hybrid coatings, while no complex apparatus is needed. Specifically, based on the biomimetic adhesion of polydopamine (PDA), we used it as a binder to adhere TiO2 nanoparticles and built rough microstructure on fabric. In this way, we obtained TiO2-PDA treated fabric with special wettability. These TiO2-PDA treated samples owned superamphiphilicity in air, underwater superoleophobicity (underwater oil contact angles (OCAs) > 150°), underoil superhydrophobicity (underoil water contact angles (WCAs)> 150°), excellent multiresistance; and can separate polar/nonpolar liquid mixture effectively. It also owned superaerophobicity underwater (underwater bubble contact angles (BCAs) > 150°). The proposed TiO2-PDA coatings are highly expected to be employed for real situation of water pollution remediation, self-cleaning, oil extraction and harsh chemical engineering issues.

The timely biochemical detection of environmental pollutants or infectious disease is a predominant challenge for global health and people living in remote areas. However, the energy supply is still difficult for both the pretreatment and test steps, especially for diagnostics in resource-limited environments or outdoor point-of-care testing. Herein, we demonstrate a hand-powered triboelectric nanogenerator (TENG) system, which can simultaneously accomplish centrifugal pretreatment and analysis without an additional power supply. The complete separation of plasma from red blood cells can be achieved within 1.5 min at an operation frequency of 1 Hz. Besides, according to the impressive high rotational speed of 7500 rpm, the rotating mechanical energy can be efficiently recycled by the TENG to power different electronic devices, such as an electronic watch or thermometer. As a demonstration, the pretreatment of lake water and the detection of hydrogen peroxide contained in it has been realized. The combination of the system with different types of sensors will further promote its applications in multifarious biochemical detections. Moreover, this TENG system is effective, field-portable and ultra-low cost, and is promising for battery-free point-of-care diagnostic systems for outdoor or harsh environments.

Despite significant advances in double-crystalline coil–coil block copolymers (BCPs), investigations into double-crystalline all-conjugated rod–rod BCPs have been comparatively fewer and are limite...

A new group of energetic metastable intermixed composites (MICs) was designed and fabricated by means of the spray granulation technique. These MICs are composed of aluminum (Al) as the fuel, ammonium perchlorate (AP) and polyvinylidene fluoride (PVDF) as the co-oxidizer. The AP/PVDF ratio was optimized by taking the maximum energy release as the criteria. A minor content of graphene oxide (GO) was also doped in the MICs to act as both lubricant and catalyst. It was shown that Al@AP/PVDF with 0.2% GO has the greatest density (2.57 g·cm–3) and highest heat of reaction (5999.5 J·g–1). These values are much higher than those of Al@AP/PVDF (2.00 g·cm–3 and 5569.8 J·g–1). The inclusion of GO increases the solid-state reaction rate of Al@AP/PVDF and improves the thermal stability. The flame propagation rate was increased up to 4.71 m·s–1 by doping with 0.2% GO, and was about 10.7% higher than that of Al@AP/PVDF. Al@AP/PVDF-GO has a better interfacial contact and particle distribution, which results in an improved heat-transfer rate, freedom from the agglomeration of nano-Al particles, and an improved combustion reaction rate. This work demonstrates a new strategy to improve the energy release rate and combustion efficiency of Al-based MICs.

Despite recent impressive advances in synthesis of all-conjugated diblock copolymers via facile quasi-living Grignard metathesis (GRIM) polymerization, it remains challenging to achieve well-define...

Density functional theory calculations were used to investigate the reaction mechanisms on [3 + 2] cycloaddition reactions of azides with metal carbyne complexes. Our results reveal that the formation of a 1,4-metallatriazole regioisomer is a kinetically favorable process in comparison with the formation of 1,5-metallatriazole. Aromaticity plays an important role in stabilizing the products in these reactions. Further analyses show that the electron-donating ligand on metal centers or the electron-withdrawing group on the azide could accelerate the [3 + 2] cycloaddition reaction. All of these findings could be useful for experimental chemists to develop "click reactions" in organometallic chemistry.

To demonstrate the discrepancies of the international standards on compatibility evaluation for energetic additives, a comparative study on compatibility of three typical graphene-based catalysts with common energetic ingredients has been done by using DSC and VST methods. Based on some unusual findings, further suggestions are proposed on improvement in the compatibility evaluation standard. The compatibility results from DSC and VST methods for HMX/GT-Ni, HMX/GC-Cu, AP/GC-Cu, AP/GT-Ni and RDX/GC-Cu systems are contradictory. The major discrepancies between DSC and VST results are caused by combination of contradictory nature of stabilization and catalytic effects of these additives on the corresponding energetic ingredients. It has been shown that the HMX/GC-Ni, HMX/GT-Ni, AP/GT-Ni, NC/GC-Ni, NC/GT-Ni, NC/GT-Cu and NC/GA-Cu mixtures have good compatibility, and the RDX/GC-Ni, AP/GC-Ni and NC/GC-Cu mixtures have moderate compatibility. In general, the copper-based additives even under the stabilization of graphene oxide are not so compatible with nitramine oxidizers and AP. These results indicate that each of the evaluation standards on compatibility has its own feature and limitation. The DSC standard is probably not suitable for the evaluation of the compatibility of GC-Ni, GC-Cu, GT-Ni, GT-Cu and GA-Cu with energetic ingredients. The compatibility assessment cannot simply rely on the available standards, and more comprehensive evaluation procedures need to be established according to the nature of the materials evaluated.

In this paper, the composites of a newly insensitive high explosive 2,4,6-triamino-5-nitropyrimidine-1,3-dioxide (ICM-102) with nanosized metals (Al, Co, Mg, Si, Ti, and Zr) and nanosized metal oxides (CuO and Fe2O3) have been prepared and investigated in terms of thermal reactivity. The catalytic effects on the thermal decomposition of ICM-102 composites have been investigated by TGA-DSC technique. Among all the composites, ICM-102/Co shows the minimum residue rate of 1.57 wt % and ICM-102/Si shows the maximum heat release of 1001.9 J g–1. The kinetic parameters for the catalytic decomposition of ICM-102 have been obtained. The activation energy (Ea) of ICM-102 decomposition is within 197.9–212.0 kJ mol–1. Compared with ICM-102, the Ea of ICM-102/Si decomposition was decreased by about 90 kJ mol–1. The decomposition gaseous products of ICM-102 and its composites have been analyzed by the TG-MS technique. It has been shown that the main gaseous products are H2O, C2H4, C3, and C2N or C3H2. The ICM-102 deco...

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

In this paper, the 2D (two-dimensional) high nitrogen triaminoguanidine-glyoxal polymer (TAGP) has been used to dope HMX crystals. Various constraint TAGP-doped HMX crystals (qy-HMX) with higher density and better stability have been obtained due to strong constraint interactions between dopant and HMX molecules. The structure and thermal reactivity properties of qy-HMX are unexpectedly largely affected by a slight change in the way of co-crystallization/precipitation under the same precursor conditions. In particular, the density of qy-HMX could be largely changed in the range of 0.94 g cm−3 to 2.12 g cm−3 due to varied doping state, depending on the crystallization conditions. These qy-HMX crystals are more thermally stable than HMX, showing either no polymorphic transition or increased transition temperature. As a typical example, the polymorphic transition of qy-HMX-211 with doping amount of 21.1 wt% was excluded due to formation of a completely new more stable phase of HMX. The qy-HMX-341 has the highest heat release (1869 J g−1), even higher than that of HMX. The average Ea (activation energy) for the polymorphic transition of qy-HMX-341 is about 334.1 kJ mol−1, following a random chain scission model (L2), whereas it is 222 kJ mol−1 for HMX. The Ea for thermal decomposition of qy-HMX-341 is 215.7 kJ mol−1, which is 39.8 kJ mol−1 lower than that of HMX. Therefore, the qy-HMX crystal has high potential to be used as a promising high explosive to replace HMX for various applications in the future.

Hexanitrohexaazaisowurtzitane (CL-20) is a well-known high energy density nitramine, but it is of high sensitivity and has the problem of polymorphic transition. In order to reduce the sensitivity of e-CL-20 and improve the stability of its crystal structure, the polydopamine (PDA)-coated graphene oxide (GO) was used to dope e-CL-20 crystals by strategy of in-situ coating followed with a solvent-non-solvent crystallization process. It has been shown that modified CL-20 crystals with the best performances are of polygon shape with a smooth surface and with the average diameter of 16 μm, much smaller than that of raw e-CL-20 (140 μm). In addition, the doping can either improve the polymorphic transition temperature up to 19.0 °C or exclude such a transition due to formation of completely new crystal phase with better stability, depending on the type and content of the dopants. The density of a certain GO@PDA modified CL-20 is even slightly higher than that of pristine e-CL-20 due to better assembling of the molecules under the nucleation of the dopants. CL-20/PDAG-2 does not show any polymorphic transition peak. Moreover, the XRD spectrum of CL-20/PDAG-2 also demonstrates that it is a completely new crystal phase better than the other four reported ones in terms of thermal stability.

Wearable pressure sensors, as essential components of flexible wearable electronics, may play important roles in early diagnosis and mortality prevention for cardiovascular healthcare. However, traditional self-powered pressure sensors can hardly obtain both high sensitivity and wide pressure range, which makes perceiving both cardiac and vascular signals in a wearable self-powered way challenging as these physiological signals not only have imperceptible changes but also span a broad pressure range. Here, we develop a flexible hierarchical elastomer tuned self-powered pressure sensor, which achieves both high-sensitivity and wide pressure range, showing a high sensitivity of 7.989 V kPa−1 and wide pressure range of 0.1–60 kPa simultaneously. Fast response (40 ms) and high signal noise ratio (38 db) with good stability are also achieved. We demonstrate that the self-powered pressure sensor can not only sensitively monitor pulse, artery and heart condition but also monitor the wide range blood pressure, which satisfies the diverse needs of wearable cardiovascular healthcare. As most of the pressure related to human interface is less than 50 kPa, we envision the sensor holds great potential in wearable electronics, mobile healthcare and human-machine interaction.

Combustion is a kind of reacting process involves fluid mechanics and chemical reactions at the same time. In the past decades, little attention has been paid to the improvement on the heat and mass transfer rate of EMs, especially for metastable intermixed composites (MICs). In this paper, an Al-based MIC (EF@EMOF) with modified chemical kinetics as well as improved heat and mass transfer rate was prepared by precisely designing the reaction process and introducing energetic metal organic frameworks (EMOF) with high specific surface area as the reactants. The overall reaction process includes the activation of n-Al by eliminating Al2O3, decomposition of EMOF producing metal oxide, followed by exothermic reactions between the activated n-Al with metal oxide and PVDF. Results show that obtained MIC has significantly increased heat release (3464 J g−1), burning rate (more than 5 times faster than that of mechanically mixed one), and improved combustion efficiency. Furthermore, it is found that the decomposition of EMOF as well as the etching reaction generates massive gas products on the interface layer which avoid the sintering and form lots of holes. Those holes, in return, provide new channels for the further reaction, thus significantly improving the energy output and chemical reaction kinetics.

It has been demonstrated in this paper that the tea polyphenols (TP) can easily adhere to the surface of particles through self-polymerization, even these particles are very hydrophobic. In this paper, a method of in-situ polymerization of TP has been used to coat n-Al powder. Then, Bi(IO3)3 crystal is grown on TP as an interfacial layer to obtain core-shell iodine-based MICs (n-Al@TP@Bi(IO3)3). Various characterization techniques are used to investigate the prepared core-shell MICs, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermal analysis, mass spectrum (MS), bomb calorimetry and high-speed camera. The results show that the obtained novel MICs are uniformly and densely distributed. The n-Al@TP@Bi(IO3)3 has higher reactivity and heat release than the traditional mechanical mixture, and the initial reaction temperature is reduced by about 30 °C caused by the decomposition-promoting effect of the decomposition product of TP (carbon) on Bi(IO3)3. and the volume reaction heat of n-Al@TP@Bi(IO3)3 (21.246 kJ cm−3) enhances by 11.3%. The results of combustion experiments show that the burning rate of n-Al@TP@Bi(IO3)3 is above 3.4 m s−1, which is 4 times that of Al/ Bi(IO3)3 (0.9 m s−1). Moreover, the combustion efficiency is higher and the agglomeration of the condensed combustion products is greatly decreased. Various other core-shell structured MICs with tunable reactivity could be easily prepared by using similar interfacial binding materials by using our strategy as a guidance.

Flexible pressure sensors possess promising applications in artificial electronic skin, intelligence robot, wearable health monitoring, flexible physiological signal sensing, etc. Herein, we design a flexible pressure sensor with robust stability, high sensitivity, and large linear pressure region on the basis of tetrafluoroethylene-hexafluoropropylene-vinylide (THV)/cyclic olefin copolymer (COC) piezoelectret nanogenerator. According to the theoretical analysis for piezoelectret nanogenerators with imbalanced charge distribution, THV and COC are utilized to promote the electric field inside the piezoelectret for output voltage enhancement. Meanwhile, the compression property of the piezoelectret nanogenerator is facilely tuned. Owing to high inner electric field and optimized compression property, the THV/COC piezoelectret nanogenerator exhibits a high sensitivity of 30 mV/kPa, which is 10 times higher than that of the traditional cellular polypropylene piezoelectret. Simultaneously, the linear pressure region reaches 150 kPa with excellent linearity ( R2 = 0.99963). The device is demonstrated to realize wearable pressure sensing with a wide pressure range from finger typing to fist hammering. This study presents a fabrication strategy for piezoelectret nanogenerators with high sensitivity and large linear pressure region, paving the way for development of wearable and flexible pressure sensing networks.

Glutathione S-transferases (GSTs) are important plant proteins involved in biotic and abiotic stress responses. A gene from Juglans regia, JrGSTTau1 was previously cloned and functionally characterized as an enzyme involved in improving cold tolerance in plants. To clarify the functional mechanism of JrGSTTau1 and its role in stress response, here, the JrGSTTau1 promoter including the up-stream regulators was examined using yeast one-hybrid together with transient expression assays, and the osmotic stress response ability was confirmed by comparing with wild-type plants. The 1500 bp JrGSTTau1 promoter displayed high GUS expression activity and was enhanced by mannitol stress. The promoter is composed of abundant cis-elements, some of which were osmotic stress response-related motifs, such as ABRE, DRE and MYB, indicating that the expression of JrGSTTau1 is regulated by potential up-stream regulators under abiotic stress. The transcription factors (TFs) of JrDREB2A, JrMYC2, JrMYB44, JrDof1 and JrWRKY7 were identified, which shared a similar response with JrGSTTau1 when exposed to PEG6000 in walnut leaf and root. These results implied that JrDREB2A, JrMYC2, JrMYB44, JrDof1 and JrWRKY7 may act as up-stream regulators of JrGSTTau1 to regulate or combine functionality with JrGSTTau1 in osmotic stress response. Furthermore, compared with the WT plants, the transgenic tobacco plants that overexpress JrGSTTau1 showed improved tolerance to drought induced by osmotic stress, in which antioxidant enzymes, proline and reactive oxygen species (ROS) are involved. Our results demonstrated the positive role played by JrGSTTau1 in osmotic tolerance, which is regulated by multiple up-stream regulators.

Given a raw LC–MS dataset, it is often required to rapidly generate initial hypotheses, in conjunction with other ‘omics’ datasets, without time-consuming lipid verifications. Furthermore, for meta-analysis of many datasets, it may be impractical to conduct exhaustive confirmatory analyses. In other cases, samples for validation may be difficult to obtain, replicate or maintain. Thus, it is critical that the computational identification of lipids is of appropriate accuracy, coverage, and unbiased by a researcher’s experience and prior knowledge. We aim to prescribe a systematic framework for lipid identifications, without usage of their characteristic retention-time by fully exploiting their underlying mass features. Initially, a hybrid technique, for deducing both common and distinctive daughter ions, is used to infer parent lipids from deconvoluted spectra. This is followed by parent confirmation using basic knowledge of their preferred product ions. Using the framework, we could achieve an accuracy of ~ 80% by correctly identified 101 species from 18 classes in Chinese hamster ovary (CHO) cells. The resulting inferences could explain the recombinant-producing capability of CHO-SH87 cells, compared to non-producing CHO-K1 cells. For comparison, a XCMS-based study of the same dataset, guided by a user’s ad-hoc knowledge, identified less than 60 species of 12 classes from thousands of possibilities. We describe a systematic LC–MS-based framework that identifies lipids for rapid hypothesis generation.

Three silicone surfactants, 3-tris(trimethylsiloxy)silylpropyl sulfonate with different alkaline counterions (lithium, sodium, and potassium), were synthesized for the first time. Their chemical structures were confirmed by FT-IR spectra, 1H NMR, and ESI-MS, and their behaviors in aqueous solutions were investigated by surface tensiometry, electrical conductivity, dynamic light scattering, and different transmission electron microscopy techniques. These anionic silicone surfactants exhibited remarkable surface activity and could reduce the surface tension of water to as low as 19.8 mN/m at the critical aggregate concentration (CAC). The adsorption and aggregation behaviors of these surfactants were assessed by determining the adsorption efficiency, minimum average area per surfactant molecule, and thermodynamic parameters. The cryo-TEM results verified that these molecules could form vesicles in water above the CAC. Moreover, the lowest surface tension, the smallest CAC value, and the largest aggregate si...

High-speed optical communication systems are built for real-time, massive and remote information exchange. However, any power outage will paralyse the systems and cause a huge loss. Here we constructed a self-powered long-distance optical communication system (SLOCS) utilizing output enhanced parallel connected electret nanogenerators (NGs) as a backup power for the power outage. The output current of the electret NG was promoted from 1.45 μA to 8.14 μA through optimizing the thickness of the electret film. In the SLOCS, a coded message was successfully transmitted for 50 meters by pressing electret NGs. The as-fabricated SLOCS paves the way to a simple and cost-effective strategy for developing a reliable emergency communication system in case of power outage, simultaneously promoting the progress of self-powered electronics.

Wearable active sensors have extensive applications in mobile biosensing and human–machine interaction but require good flexibility, high sensitivity, excellent stability, and self-powered feature. In this work, cellular polypropylene (PP) piezoelectret was chosen as the core material of a sensitivity-enhanced wearable active voiceprint sensor (SWAVS) to realize voiceprint recognition. By virtue of the dipole orientation control method, the air layers in the piezoelectret were efficiently utilized, and the current sensitivity was enhanced (from 1.98 pA/Hz to 5.81 pA/Hz at 115 dB). The SWAVS exhibited the superiorities of high sensitivity, accurate frequency response, and excellent stability. The voiceprint recognition system could make correct reactions to human voices by judging both the password and speaker. This study presented a voiceprint sensor with potential applications in noncontact biometric recognition and safety guarantee systems, promoting the progress of wearable sensor networks.

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 c...

Effective development of host cells for therapeutic protein production is hampered by the poor characterization of cellular transfection. Here, we employed a multi-omics-based systems biotechnology approach to elucidate the genotypic and phenotypic differences between a wild-type and recombinant antibody-producing Chinese hamster ovary (CHO) cell line. At the genomic level, we observed extensive rearrangements in specific targeted loci linked to transgene integration sites. Transcriptional re-wiring of DNA damage repair and cellular metabolism in the antibody producer, via changes in gene copy numbers, was also detected. Subsequent integration of transcriptomic data with a genome-scale metabolic model showed a substantial increase in energy metabolism in the antibody producer. Metabolomics, lipidomics, and glycomics analyses revealed an elevation in long-chain lipid species, potentially associated with protein transport and secretion requirements, and a surprising stability of N-glycosylation profiles between both cell lines. Overall, the proposed knowledge-based systems biotechnology framework can further accelerate mammalian cell-line engineering in a targeted manner.

The trends in miniaturization of electronic devices give rise to the attention of energy harvesting technologies that gathers tiny wattages of power. Here this study demonstrates an ultrathin flexible single electrode triboelectric nanogenerator (S-TENG) which not only could harvest mechanical energy from human movements and ambient sources, but also could sense instantaneous force without extra energy. The S-TENG, which features an extremely simple structure, has an average output current of 78 μA, lightening up at least 70 LEDs (light-emitting diode). Even tapped by bare finger, it exhibits an output current of 1 μA. The detection sensitivity for instantaneous force sensing is about 0.947 μA MPa−1. Performances of the device are also systematically investigated under various motion types, press force, and triboelectric materials. The S-TENG has great application prospects in sustainable wearable devices, sustainable medical devices, and smart wireless sensor networks owning to its thinness, light weight, energy harvesting, and sensing capacities.

A theory is presented for the transmission of transverse magnetic waves through a finite number of subwavelength slits in metal film. While a single slit achieves the single channel limit on resonance, multiple slits show super-transmission exceeding the single channel limit. The phenomenon of super-transmission is revealed as a result of cross-coupling of modes and confirmed by simulations. The influence of finite permittivity in the IR and microwave regime is included by perturbative corrections to the theory. The theory agrees quantitatively with past experiments and finite-difference time-domain simulations. By considering two or more modes in the slit region, our theory provides an approach to the analysis of cross-coupling among slits, which allows for super-transmission and features of a Fano resonance.