Opto-electrical and polarization performance of a mesa-structured InGaAs PIN detector integrated with subwavelength aluminum gratings.

Polarization detection in the short-wave infrared (SWIR) region presents broad applications in target-background contrast enhancement, underwater imaging, material classification, etc. A mesa structure can prevent electrical cross talk due to its intrinsic advantages, making it potentially suited to meet the need for manufacturing smaller-sized devices to save cost and shrink volume. In this Letter, mesa-structured InGaAs PIN detectors with a spectral response ranging from 900 nm to 1700 nm and a detectivity of 6.28 × 1011 cm·Hz1/2/W at 1550 nm and -0.1 V bias (room temperature) have been demonstrated. Furthermore, the devices with subwavelength gratings in four orientations show obvious polarization performance. Their extinction ratios (ERs) can reach 18:1 at 1550 nm and their transmittances are over 90%. Such a polarized device with a mesa structure could realize miniaturized SWIR polarization detection.

Demonstration of SWIR Silicon-Based Photodetection by Using Thin ITO/Au/Au Nanoparticles/n-Si Structure.

Plasmonic photodetection based on the hot-electron generation in nanostructures is a promising strategy for sub-band detection due to the high conversion efficiencies; however, it is plagued with the high dark current. In this paper, we have demonstrated the plasmonic photodetection with dark current suppression to create a Si-based broadband photodetector with enhanced performance in the short-wavelength infrared (SWIR) region. By hybridizing a 3 nm Au layer with the spherical Au nanoparticles (NPs) formed by rapid thermal annealing (RTA) on Si substrate, a well-behaved ITO/Au/Au NPs/n-Si Schottky photodetector with suppressed dark current and enhanced absorption in the SWIR region is obtained. This optimized detector shows a broad detection beyond 1200 nm and a high responsivity of 22.82 mA/W at 1310 nm at -1 V, as well as a low dark current density on the order of 10-5 A/cm2. Such a Si-based plasmon-enhanced detector with desirable performance in dark current will be a promising strategy for realization of the high SNR detector while keeping fabrication costs low.

Enhanced light extraction from AlGaInP-based red light-emitting diodes with photonic crystals.

The photonic crystal (PC) has been demonstrated to be very effective in improving the extraction efficiency of light-emitting diodes (LEDs). In this paper, high-brightness AlGaInP-based vertical LEDs (VLEDs) with surface PC (SPCLED) and embedded PC (EPCLED) were successfully fabricated. Compared with normal LED (NLED), photoluminescence intensities of SPCLED and EPCLED have been improved up to 30% and 60%, respectively. And the reflection patterns of SPCLED and EPCLED were periodic bright points array, showing the ability to control light in PC. Electroluminescent measurements show that three kinds of LEDs have similar threshold voltages. Simultaneously, the light output power (LOP) of SPCLED and EPCLED has been improved up to 24% and 11% at 200 mA, respectively, in comparison to NLEDs. But the LOP decays earlier for EPCLED due to the excessive heat production. Furthermore, it is demonstrated that the SPCLED and EPCLED luminous uniformity is better. This kind of high brightness PCLED is promising in improving the properties of all kinds of LEDs, especially mini LEDs and micro LEDs.

Piezotronic effect tuned AlGaN/GaN high electron mobility transistor.

The piezotronic effect utilizes strain-induced piezoelectric polarization charges to tune the carrier transportation across the interface/junction. We fabricated a high-performance AlGaN/GaN high electron mobility transistor (HEMT), and the transport property was proven to be enhanced by applying an external stress for the first time. The enhanced source-drain current was also observed at any gate voltage and the maximum enhancement of the saturation current was up to 21% with 15 N applied stress (0.18 GPa at center) at -1 V gate voltage. The physical mechanism of HEMT with/without external compressive stress conditions was carefully illustrated and further confirmed by a self-consistent solution of the Schrödinger-Poisson equations. This study proves the cause-and-effect relationship between the piezoelectric polarization effect and 2D electron gas formation, which provides a tunable solution to enhance the device performance. The strain tuned HEMT has potential applications in human-machine interface and the security control of the power system.

The efficacy and safety of reslizumab for inadequately controlled asthma with elevated blood eosinophil counts: A systematic review and meta-analysis.

CONTEXT: Reslizumab is a humanised anti-interleukin 5 monoclonal antibody that disrupts eosinophil maturation and promotes programmed cell death. OBJECTIVE: We carried out a systematic review and meta-analysis to assess the efficacy and safety of the drug in patients with inadequately controlled, eosinophilic asthma. DATA SOURCES: The search included the following databases: MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. STUDY SELECTION: A literature review was performed to identify all published randomized double-blind, placebo-controlled trials of reslizumab for the treatment of inadequately controlled, eosinophilic asthma. DATA EXTRACTION: Two reviewers independently extracted and verified pre-defined data fields. RESULTS: Four publications including 5 RCTs that compared reslizumab with placebo. For the comparison of reslizumab with placebo, asthma exacerbation (odds ratio (OR) = 0.46, 95% confidence interval (CI) = 0.35 to 0.59, p <0.00001); a forced expiratory volume in 1 s (FEV1) (the standardized mean difference (SMD) = 0.16, 95%CI = 0.10 to 0.23, p <0.00001); Asthma Control Questionnaire (ACQ) score (the SMD = -0.26, 95%CI= -0.36 to -0.16, p <0.00001); blood eosinophil counts (the SMD = -475.62, 95%CI = -528.41 to -422.83, p <0.00001). Safety assessments included the proportion of individuals who withdrawn due to adverse event (AE) (OR = 0.60 95%CI = 0.38 to 1.17, p = 0.16) indicated that reslizumab was well tolerated. LIMITATIONS: The article didn't research the safety, efficacy of reslizumab with longer term. CONCLUSIONS: This meta-analysis indicates that reslizumab to be an effective and safe treatment for inadequately controlled, eosinophilic asthma.

Effectiveness of the conservative therapy for spontaneous isolated iliac artery dissection: Preliminary results.

Purpose To investigate the effectiveness of conservative therapy for spontaneous isolated iliac artery dissection (SIIAD). Methods From February 2006 to May 2016, all patients with SIIAD were included and analyzed. The diagnosis of SIIAD was made based on contrast-enhanced computed tomography. The imaging morphologic characteristics, treatments, and outcomes for each patient were analyzed. Results A total of 11 patients (10 male and 1 female, age 71.1 ± 7.8 years) were included in this study. Of the 11 patients, 8 patients were asymptomatic and the SIIADs were discovered during the course of computed tomography for other diseases, and 3 patients were symptomatic. Initial computed tomography findings: iliac arterial calcification ( n = 7); compression of the true lumen ( n = 6), with stenosis of the true lumen from 25% to 50% ( n = 3) and ≥ 50% ( n = 3); thrombosed false lumen partially ( n = 4), and no thrombosis in false lumen ( n = 7); dissecting aneurysm ( n = 11); entry points ( n = 11); re-entry points ( n = 1); no dissection extended to the internal iliac or common femoral artery. Conservative treatment was performed in six patients, and the remaining five patients need no treatment. During 23.3 ± 14.2 months follow-up, none recurred symptoms and signs of symptomatic SIIAD; partial remodeling of SIIAD was achieved in four patients, and the remaining seven patients with no change of SIIAD. There was no presence of new false lumen enhancement on contrast-enhanced computed tomography during follow-up. Conclusions SIIAD without arterial rupture or lower limb necrosis can be safely treated with conservative therapy.

Piezo-Phototronic Effect Controlled Dual-Channel Visible light Communication (PVLC) Using InGaN/GaN Multiquantum Well Nanopillars.

Visible light communication (VLC) simultaneously provides illumination and communication via light emitting diodes (LEDs). Keeping a low bit error rate is essential to communication quality, and holding a stable brightness level is pivotal for illumination function. For the first time, a piezo-phototronic effect controlled visible light communication (PVLC) system based on InGaN/GaN multiquantum wells nanopillars is demonstrated, in which the information is coded by mechanical straining. This approach of force coding is also instrumental to avoid LED blinks, which has less impact on illumination and is much safer to eyes than electrical on/off VLC. The two-channel transmission mode of the system here shows great superiority in error self-validation and error self-elimination in comparison to VLC. This two-channel PVLC system provides a suitable way to carry out noncontact, reliable communication under complex circumstances.

Temperature and pH dual response flexible silica aerogel with switchable wettability for selective oil/water separation.

Silica aerogels are attractive oil-absorbing agents due to their low density, high porosity. However, how to discharge the oil which adsorbed by silica aerogels is a difficult issue. To address this challenge, new separation strategies with high efficiency are needed. In this study, we prepared the temperature and pH dual response flexible silica aerogel have temperature response and pH response effect, which can change its wettability by adjusting temperature or pH. On the one hand, the temperature and pH responsive flexible silica aerogel can be used to adsorb water at the temperature below 34.73 °C or pH > 7. On the other hand, it can adsorb oil at a temperature above 34.73 °C or pH < 7. The automatic desorption of oil can be achieved without consuming additional energy and damaging the pore structure. Therefore, the sample could continuously adsorb and filtrate efficiently and realize the recovery of oil and adsorption materials.

Transcriptome analysis reveals key genes and pathways for prickle development in Zanthoxylumarmatum.

Zanthoxylum armatum is an economically important tree species. However, well-developed prickles on its stems and leaves pose serious challenges in terms of management and harvesting. To investigate the molecular mechanism underlying prickle development, we sequenced different stages of prickle morphological development and transcriptomes of different tissues in the root tips (Gen), leaf buds (Ya), and fruits of Z. armatum. The results revealed that proteins related to cell division and genes related to the growth hormone signaling pathway were highly expressed in the prickle just protrusion (PC1). In addition, a high expression of lignin biosynthesis genes was observed during the developmental onset of lignification (PC2) and prickle lignification (PC3). These findings indicate that phenylpropanoid biosynthesis and plant hormone signal transduction are key pathways for the completion of lignification development in the prickle. During prickle development, ZaMYB2 and ZaWRKY3 were significantly upregulated in PC2 and PC3, suggesting their possible involvement in prickle development. Transcriptome and qRT-PCR analyses revealed differential gene expression of zaPAL3, za4CLL1, zaCOMT1, ZaWRKY3, and ZaCCD31 in the Gen, Ya, newly formed fruit (ZaF1), newly oil-spotted fruits (ZaF2), PC1, PC2, and PC3 of Zarmatum. zaCCD31 was highly expressed in leaf buds, whereas Za4CLL1 was highly expressed in root tips. During the lignification of prickles, the relative expression of genes including zaMYB2 increased gradually; however, the relative expression of zaCCD31 decreased during this process. Therefore, we inferred that these genes might be closely related to prickle development. Notably, zaMYB2 was expressed at higher levels in PC2 and PC3 than in PC1 and was not expressed in Gen, Ya, ZaF1, and ZaF2. Therefore, zaMYB2 is a key gene involved in prickle development of Z. armatum that exhibited tissue-specific expression. This study establishes a foundation for future analyses of the molecular mechanism underlying prickle development in Z. armatum.

A preliminary study on the application of bone marrow stromal cell sheet on the formation of functional tissue-engineered bone in dogs.

PURPOSE: The aim of this study was to construct functional tissue-engineered bone in dogs using cell sheet engineering, a new technique to gain and transfer seed cells. MATERIALS AND METHODS: Demineralized bone matrixes, prepared from homologous bone, were coated with recombinant human bone morphogenetic protein-2. Bone marrow stromal cells (BMSCs) were isolated and subcultured. Osteogenic-induced BMSCs were incubated in a temperature-responsive culture dish to form the BMSC sheet. The complex of demineralized bone matrix, recombinant human bone morphogenetic protein-2, and BMSCs wrapped with BMSC sheets was implanted around the blood vessels of the latissimus dorsi muscle in the experimental side, and the same complex without BMSC sheets was implanted around the blood vessels of the latissimus dorsi muscle on the other side as a control. At 4, 8, 12, and 16 weeks after implantation, the implants were removed for radiographic evaluation, descriptive histologic observation, and histologic quantitative analysis. RESULTS: Radiographic analysis showed that the optical density of the tissue-engineered bone on the 2 sides increased with time. However, the optical density of the experimental side was significantly greater than that of the control side at the same points. Sixteen weeks after implantation, mature lamellar bone was formed in the experimental side, with red bone marrow in the bone marrow cavity. In contrast, the control side exhibited significantly less lamellar bone. Histologic quantitative analysis showed that the experimental side exhibited significantly more bone per area compared with the control side. CONCLUSION: BMSC sheet engineering may be useful to construct functional tissue-engineered bone.

Preparation of Super-Flexible Silica Aerogel and Its Application in Oil-Water Separation.

Using silica as the precursor, and methyltrimethoxysilane and dimethyldimethoxysilane as the silicon sources, a super-flexible hydrophobic lipophilic gel solid was prepared via hydrolysis, drying, solvent replacement, and atmospheric-pressure drying. The characterization test showed that the sample had good flexibility, hydrophobicity, an amorphous structure, and a hydrophobic contact angle of 137°. Through the adsorption separation experiment, it was concluded that the adsorption separation rate of aerogel to oil substances is related to the viscosity of the oil substances. The hydrophobic and oleophilic properties of flexible silicon aerogel materials can be applied to many aspects, such as crude oil leakage and kitchen waste oil recovery, with broad future development prospects and great research significance.

Ultrasensitive and Self-Powered Multiparameter Pressure-Temperature-Humidity Sensor Based on Ultra-Flexible Conductive Silica Aerogel.

The application of silica aerogel has been limited because of its poor mechanical properties. In order to expand the application scope of silica aerogel, this study fabricated an ultra-flexible conductive silica aerogel as a multiparameter sensor. The sample is fabricated by introducing poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) on a base of ultra-flexible silica aerogel, which was prepared by a diene synthesis reaction at atmospheric pressure. The pressure, temperature, and humidity can be converted into electrical signals. The pressure sensitivity can reach up to 54.88 kPa-1, and the detection limit is as low as 5 Pa. The temperature resolution is up to 0.1 K, and the response time of humidity is within 4 s. More importantly, the developed multiparameter sensor can be self-powered to realize multiparameter sensing of pressure, temperature, and humidity. The ultra-flexible conductive silica aerogel is a promising candidate for monitoring human activities and fire-affected areas.

Ultrafast One-Step Deposition Route to Fabricate Single-Crystal CsPbX3 (X = Cl, Cl/Br, Br, and Br/I) Photodetectors.

Inorganic perovskites have received much attention due to their stability and high performance in luminescence, photoelectric conversion, and photodetection. However, perovskite optoelectronic devices prepared by the solution technique are still suffering from time-consuming and complex operations. In this paper, a single-crystal perovskite-based photodetector (PD) is prepared by very fast one-step deposition of synthesizing microplatelets (MPs) on the electrode directly. The saturated precursor is carefully optimized by adding appropriate antisolvent chlorobenzene (CB) to fabricate the MPs with their PL wavelength ranging from 418 to 600 nm. Furthermore, the PDs with a low dark current on order of nanoangstroms, high responsivity and detectivity of up to 10.7 A W-1 and 1012 Jones, respectively, and an ultrafast response rate featured by 278/287 µs (rise/decay time) are achieved. These all-inorganic perovskite PDs with a simple fabricating process and tunable detection wavelength meet the evolution tendency of PDs toward low cost and high performance, which is a high-profile strategy to realize high-performance perovskite PDs.

PVA-assisted CNCs/SiO2 composite aerogel for efficient sorption of ciprofloxacin.

Efforts to develop a green, inexpensive and effective adsorbent are crucial for eliminating antibiotics in polluted water. The sorption capacity of the as-prepared polyvinyl alcohol (PVA)-assisted cellulose nanocrystals/SiO2 (CNCs/SiO2) composite aerogel to ciprofloxacin (CIP) rises with the increase of temperature and initial concentration. Reverse trend of sorption capacity can be found when increasing the adsorbent dosage of adsorbent. The optimal pH value for the sorption is proved to be 4. It's found in the uniaxial compression test that the maximum load that PVA-assisted aerogels can withstand is nearly 100 times than that of non-PVA aerogels. Sorption results confirm that the Pseudo-second order (R2 = 0.9885) and Langmuir models (R2 = 0.9959) fit well to sorption kinetics and equilibrium data, respectively. The rate constant differs from the initial concentration of CIP according to the Pseudo-second order model. The composite aerogel sorption capacity of Langmuir (qmax) for CIP was 163.34 mg·g-1. The thermodynamic studies showed that the sorption process is endothermic with the value of enthalpy change of 41.032 kJ/mol. Hydrogen bonding, π-π interaction, hydrophobic and electrostatic interactions are the dominant mechanisms of CIP sorption by the PVA-assisted CNCs/SiO2 composite aerogel.

[Study on ITS sequences of Aconitum vilmorinianum and its medicinal adulterant].

OBJECTIVE: To analyze and compare the ITS sequences of Aconitum vilmorinianum and its medicinal adulterant Aconitum austroyunnanense. METHODS: Total genomic DNA were extracted from sample materials by improved CTAB method, ITS sequences of samples were amplified using PCR systems, directly sequenced and analyzed using software DNAStar, ClustalX1.81 and MEGA 4.0. RESULTS: 299 consistent sites, 19 variable sites and 13 informative sites were found in ITS1 sequences, 162 consistent sites, 2 variable sites and 1 informative sites were found in 5.8S sequences, 217 consistent sites, 3 variable sites and 1 informative site were found in ITS2 sequences. Base transition and transversion was not found only in 5.8S sequences, 2 sites transition and 1 site transversion were found in ITS1 sequences, only 1 site transversion was found in ITS2 sequences comparting the ITS sequences data matrix. By analyzing the ITS sequences data matrix from 2 population of Aconitum vilmorinianum and 3 population of Aconitum austroyunnanense, we found a stable informative site at the 596th base in ITS2 sequences, in all the samples of Aconitum vilmorinianum the base was C, and in all the samples of Aconitum austroyunnanense the base was A. CONCLUSION: Aconitum vilmorinianum and Aconitum austroyunnanense can be identified by their characters of ITS sequences, and the variable sites in ITS1 sequences are more than in ITS2 sequences.

The relationship between the accuracy of curling athletes' duration judgment and delivery performance.

Objective: Time perception is a critical point for curling athletes to have in order to successfully complete interactions between themselves and their environment. Exploring the relationship between the accuracy of duration judgment and curling athletes' performance is helpful to reveal the influencing factors on their performance and to provide a reference for the training of athletes' delivery performance. Methods: Thirty curling athletes and 30 non-athletes were recruited as participants. Using 3D modeling technology, curling videos of different situations were presented to the participants as stimulus information, and the participants were required to complete the duration judgment task. The neural activation of the participants during the entire process of duration judgment was recorded using electroencephalogram (EEG) equipment. The performance of the 30 curlers participating in the experiment was measured. Variance analyses were conducted on the collected behavioral and EEG data, and correlation and regression analyseswere conducted between behavioral data and delivery performance. Results: The accuracy of the distance judgment of curlers was higher than that of non-curlers (P < 0.05). In the stimulus video presentation stage, the power in the alpha band of curlers was higher than that of non-athletes (P < 0.05). In the task decision stage, the power in the alpha band of curlers was higher than that of non-athletes (P < 0.05), and the power in the theta band was higher than that of non-athletes (P < 0.05). There was a correlation between the accuracy of the curlers' perception of specific situational time intervals and the accuracy of delivery (P < 0.05). Regression analysis results were y = 3.422 + 1.415x. Conclusion: The accuracy of curling athletes' duration judgment is high in a specific situation. There is a correlation between the accuracy of duration judgment and delivery performance in a specific situation: the higher the accuracy of specific duration perception, the higher the performance accuracy of delivery. The cognitive strategies adopted by curlers differ from those adopted by non-athletes in the completion of duration judgment. Specifically, in a specific situation, fewer attention resources are utilized in the stimulus presentation and decision-making stages, while more memory resources are utilized in the decision-making stage to ensure higher accuracy of interval judgment. This study provides a new idea for exploring the causes of curling athletes' excellent technical performance and provides a reference for future curling research on competition training practice. Given the limitations of mobile EEG devices in this study, future studies can measure neural activity during actual delivery preparation and execution in an environment of high ecological validity to obtain more direct evidence.

Kinetic Study on High-Temperature H2S Removal over Mn-Based Regenerable Sorbent Using Deactivation Model.

The kinetics of high-temperature H2S removal over Mn/Al sorbents prepared by co-precipitation method was investigated in a fixed-bed reactor using a deactivation model. The initial sorption rate constant (k 0), deactivation rate constant (k d), apparent activation energy (E a), and deactivation energy (E d) were obtained. The k 0 and k d values of Mn/Al sorbents are much higher than those of pure Mn2O3. This indicates that Mn/Al sorbents have higher reactivity on the removal of H2S and less diffusion resistance caused by the formation of the sulfided product. The E a and E d values for the sorbent with the Mn content (wt %) of 35.4% are 38.18 and 31.05 kJ/mol, respectively. The deactivation model gives excellent predictions for the H2S breakthrough curves in the sulfidation-regeneration process.

Green and Low-Cost Natural Lignocellulosic Biomass-Based Carbon Fibers-Processing, Properties, and Applications in Sports Equipment: A Review.

At present, high-performance carbon fibers (CFs) are mainly produced from petroleum-based materials. However, the high costs and environmental problems of the production process prompted the development of new precursors from natural biopolymers. This review focuses on the latest research on the conversion of natural lignocellulosic biomass into precursor fibers and CFs. The influence of the properties, advantages, separation, and extraction of lignin and cellulose (the most abundant natural biopolymers), as well as the spinning process on the final CF performance are detailed. Recent strategies to further improve the quality of such CFs are discussed. The importance and application of CFs in sports equipment manufacturing are briefly summarized. While the large-scale production of CFs from natural lignocellulosic biomass and their applications in sports equipment have not yet been realized, CFs still provide a promising market prospect as green and low-cost materials. Further research is needed to ensure the market entry of lignocellulosic biomass-based CFs.

Inspired by Skeletal Muscles: Study of the Physical and Electrochemical Properties of Derived Lignocellulose-Based Carbon Fibers.

Skeletal muscles exhibit excellent properties due to their well-developed microstructures. Taking inspiration from nature that thick filaments and thin filaments are linked by "cross-bridges", leading to good stability and ion transport performance of muscles. In this work, extracted poplar lignin and microcrystalline cellulose (MCC) were connected by biomimetic covalent bonds, akin to biological muscle tissue, in which isophorone diisocyanate was used as the chemical crosslinking agent. Then, poplar lignin-MCC was mixed with polyacrylonitrile to serve as the precursor for electrospinning. The results show that due to the effective covalent-bond connection, the precursor fibers possess excellent morphology, smooth surface, good thermal stability, and high flexibility and toughness (average elongation-at-break is 51.84%). Therefore, after thermal stabilization and carbonization, derived lignocellulose-based carbon fibers (CFs) with a reduced cost, complete fiber morphology with a uniform diameter (0.48 ± 0.22 µm), and high graphitization degree were obtained. Finally, the electrodes fabrication and electrochemical testing were carried out. The results of electrochemical impedance spectroscopy (EIS) indicate that the Rs and Rct values of CFs supercapacitors are 1.18 Ω and 0.14 Ω, respectively. Results of cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) suggest that these CFs demonstrate great application potential in electrochemical materials.

High performance visible-SWIR flexible photodetector based on large-area InGaAs/InP PIN structure.

Mechanically flexible optoelectronic devices and systems can enable a much broader range of applications than what their rigid counterparts can do, especially for novel bio-integrated optoelectronic systems, flexible consumer electronics and wearable sensors. Inorganic semiconductor could be a good candidate for the flexible PD when it can keep its high performance under the bending condition. Here, we demonstrate a III-V material-based flexible photodetector operating wavelength from 640 to 1700 nm with the high detectivity of 5.18 × 1011 cm‧Hz1/2/W and fast response speed @1550 nm by using a simply top-to-down fabrication process. The optoelectrical performances are stable as the PDs are exposed to bending cycles with a radius of 15 mm up to 1000 times. Furthermore, the mechanical failure mode of the PD is also investigated, which suggests that the cracking and delamination failure mode are dominant in bending up and bending down direction, respectively. Such a flexible III-V material-based PD and design with stable and high performance could be a promising strategy for the application of the flexible broad spectrum detection.