Recent Advances in Broadband Photodetectors from Infrared to Terahertz.

The growing need for the multiband photodetection of a single scene has promoted the development of both multispectral coupling and broadband detection technologies. Photodetectors operating across the infrared (IR) to terahertz (THz) regions have many applications such as in optical communications, sensing imaging, material identification, and biomedical detection. In this review, we present a comprehensive overview of the latest advances in broadband photodetectors operating in the infrared to terahertz range, highlighting their classification, operating principles, and performance characteristics. We discuss the challenges faced in achieving broadband detection and summarize various strategies employed to extend the spectral response of photodetectors. Lastly, we conclude by outlining future research directions in the field of broadband photodetection, including the utilization of novel materials, artificial microstructure, and integration schemes to overcome current limitations. These innovative methodologies have the potential to achieve high-performance, ultra-broadband photodetectors.

Protective effects of METRNL overexpression against pathological cardiac remodeling.

At present, meteorin-like protein (METRNL) has been proven to be widely expressed in the myocardium and participates in the pathogenic process of various cardiovascular diseases. However, the effects of METRNL on pathological cardiac hypertrophy is still unknown. In the present study, we used a mouse model of transverse aortic constriction (TAC) surgery to mimic pathological cardiac hypertrophy and gene delivery system to overexpress METRNL in vivo. The results showed that METRNL overexpression improved TAC-induced pathological cardiac hypertrophy in mice and neonatal cardiomyocytes. In addition, METRNL overexpression diminished TAC-induced cardiac oxidative damage, inflammation and cardiomyocyte apoptosis. Moreover, the cardioprotective effect of METRNL overexpression was directly related to the activation of AMP-activated protein kinase (AMPK) and sirtuin1 (SIRT1). In summary, our data identified that METRNL may be a promising therapeutic target to mitigate pathological cardiac hypertrophy in the future.

Multimodal contrastive representation learning for drug-target binding affinity prediction.

In the biomedical field, the efficacy of most drugs is demonstrated by their interactions with targets, meanwhile, accurate prediction of the strength of drug-target binding is extremely important for drug development efforts. Traditional bioassay-based drug-target binding affinity (DTA) prediction methods cannot meet the needs of drug R&D in the era of big data. Recent years we have witnessed significant success on deep learning-based models for drug-target binding affinity prediction task. However, these models only considered a single modality of drug and target information, and some valuable information was not fully utilized. In fact, the information of different modalities of drug and target can complement each other, and more valuable information can be obtained by fusing the information of different modalities. In this paper, we introduce a multimodal information fusion model for DTA prediction that is called FMDTA, which fully considers drug/target information in both string and graph modalities and balances the feature representations of different modalities by a contrastive learning approach. In addition, we exploited the alignment information of drug atoms and target residues to capture the positional information of string patterns, which can extract more useful feature information in SMILES and target sequences. Experimental results on two benchmark datasets show that FMDTA outperforms the state-of-the-art model, demonstrating the feasibility and excellent feature capture capability of FMDTA. The code of FMDTA and the data are available at: https://github.com/bestdoubleLin/FMDTA.

Crosstalk suppression in CMOS terahertz detectors by using a mushroom-like AMC structure.

The suppression of the crosstalk in a CMOS THz detector is essential for enhancing the performance of detector arrays; however, it presents several technical challenges at the chip level. In this paper, a novel structure featuring a mushroom-like artificial magnetic conductor (M-AMC) is developed to suppress the crosstalk between CMOS THz detectors with on-chip antennas. Three-dimensional simulation results show that the M-AMC structure, which is designed by metal Al and doped-Si materials in the CMOS process, not only reduces the transmission coefficient of the electromagnetic wave between adjacent pixels but also enhances the electric field of the target pixels. A 0.65 THz detector array with a M-AMC structure based on the on-chip antenna was fabricated. Experimental results present that after implanting the M-AMC structure, the noise equivalent power (NEP) at the central frequency of pixels significantly decreases by 315.5%. Moreover, the distribution of NEP becomes more uniform, as evidenced by a reduction in the standard deviation coefficient of 26.3%. This demonstrates the effectiveness of the method in suppressing crosstalk and improving the responsivity of CMOS THz detectors, which can be used for high-performance THz detector arrays.

Impact of Various Thermistors on the Properties of Resistive Microbolometers Fabricated by CMOS Process.

Microbolometers based on the CMOS process has the important advantage of being automatically merged with circuits in the fabrication of larger arrays, but they typically suffer from low detectivity due to the difficulty in realizing high-sensitivity thermistors in the CMOS process. In this paper, two resistive microbolometers based on polysilicon and metal Al thermistors, respectively, are designed and fabricated by the standard CMOS process. Experimental results show that the detectivity of the two resistive microbolometers can reach a maximum of 1.78 ´ 109 cmHz1/2/W at 25 µA and a maximum of 6.2 ´ 108 cmHz1/2/W at 267 µA. The polysilicon microbolometer exhibits better detectivity at lower bias current due to its lower effective thermal conductivity and larger resistance. Even though the thermal time constant of the polysilicon thermistor is three times slower than that of the metal Al thermistor, the former is more suitable for designing a thermal imaging system with sensitive and low power consumption.

Wide-angle and high-efficiency flat retroreflector.

We propose a flat retroreflector that can efficiently reflect the electromagnetic waves back along its incident direction in a wide continuous range of angles. This retroreflector consists of a quadratic metalens and a flat metallic reflector at the focal plane of the former. The quadratic metalens is a dielectric pillar array encoded with a quadratic phase profile and it is embedded in the top side of the substrate. The flat reflector is on the bottom side of the substrate. The designed retroreflector has a diameter of 40 mm, a thickness of 15 mm, and a working frequency of 77 GHz. Through meta-units optimization, a retroreflection efficiency of 38.51% at ± 60° incidence and an average retroreflection efficiency of 46.39% for the incident angles from 0° to 60° can be numerically demonstrated. This flat retroreflector is easy for integration, which is promising for potential applications in the miniature wireless communication systems.

The Adsorption of H2 and C2H2 on Ge-Doped and Cr-Doped Graphene Structures: A DFT Study.

In order to find an excellent sensing material for dissolved gases in transformer oil, the adsorption structures of intrinsic graphene (IG), Ge-doped graphene (GeG), and Cr-doped graphene (CrG) to H2 and C2H2 gas molecules were built. It was found that the doping site right above C atom (T) was the most stable structure by studying three potential doping positions of the Ge and Cr atom on the graphene surface. Then, the structural parameters, density of states, and difference state density of these adsorption systems were calculated and analyzed based on the density functional calculations. The results show that the adsorption properties of GeG and CrG systems for H2 and C2H2 are obviously better than the IG system. Furthermore, by comparing the two doping systems, CrG system exhibits more outstanding adsorption performances to H2 and C2H2, especially for C2H2 gas. Finally, the highest adsorption energy (-1.436 eV) and the shortest adsorption distance (1.981 Å) indicate that Cr-doped graphene is promising in the field of C2H2 gas-sensing detection.

Nomogram to Predict Preoperative Occult Peritoneal Metastasis of Gastrointestinal Stromal Tumors (GIST) Based on Imaging and Inflammatory Indexes.

BACKGROUND: Preoperative imaging examination is the primary method for diagnosing metastatic gastrointestinal stromal tumor (GIST), but it is associated with a high rate of missed diagnosis. Therefore, it is important to establish an accurate model for predicting occult peritoneal metastasis (PM) of GIST. PATIENTS AND METHODS: GIST patients seen between April 2002 and December 2018 were selected from an institutional database. Using multivariate logistic regression analyses, we created a nomogram to predict occult PM of GIST and validated it with an independent cohort from the same center. The concordance index (C-index), decision curve analysis (DCA) and a clinical impact curve (CIC) were used to evaluate its predictive ability. RESULTS: A total of 522 eligible GIST patients were enrolled in this study and divided into training (n=350) and validation cohorts (n=172). Factors associated with occult PM were included in the model: tumor size (odds ratio [OR] 1.194 95% confidence interval [CI], 1.034-1.378; p=0.016), primary location (OR 7.365 95% CI, 2.192-24.746; p=0.001), tumor capsule (OR 4.282 95% CI, 1.209-15.166; p=0.024), Alb (OR 0.813 95% CI, 0.693-0.954; p=0.011) and FIB (OR 2.322 95% CI, 1.410-3.823; p=0.001). The C-index was 0.951 (95% CI, 0.917-0.985) in the training cohort and 0.946 (95% CI, 0.900-0.992) in the validation cohort. In the training cohort, the prediction model had a sensitivity of 82.8%, a specificity of 93.8%, a positive predictive value of 54.7%, and a negative predictive value of 98.4%; the validation cohort values were 94.7%, 85.0%, 43.9% and 99.2%, respectively. DCA and CIC results showed that the nomogram had clinical value in predicting occult PM in GIST patients. CONCLUSION: Imaging and inflammatory indexes are significantly associated with microscopic metastases of GIST. A nomogram including these factors would have an excellent ability to predict occult PM.

Recent Advances of SnO2-Based Sensors for Detecting Volatile Organic Compounds.

SnO2 based sensors has received extensive attention in the field of toxic gas detection due to their excellent performances with high sensitivity, fast response, long-term stability. Volatile organic compounds (VOCs), originate from industrial production, fuel burning, detergent, adhesives, and painting, are poisonous gases with significant effects on air quality and human health. This mini-review focuses on significant improvement of SnO2 based sensors in VOCs detection in recent years. In this review, the sensing mechanism of SnO2-based sensors detecting VOCs are discussed. Furthermore, the improvement strategies of the SnO2 sensor from the perspective of nanomaterials are presented. Finally, this paper summarizes the sensing performances of these SnO2 nanomaterial sensors in VOCs detection, and the future development prospect and challenges is proposed.

Dual-frequency CMOS terahertz detector with silicon-based plasmonic antenna.

Multi-frequency Terahertz (THz) detectors have shown great application potentials in THz imaging and sensing systems. For the first time to our knowledge, a novel dual-frequency THz detector with the stacked structure consisting of a silicon-based plasmonic antenna and a metal-based antenna in one compact unit is proposed and fabricated in standard CMOS technology. Compared with the metal antenna, the antenna based on heavy-doped poly-silicon materials enables the detector to excite localized surface plasmon resonance mode, making the effective absorption of the THz waves and thus resulting in the significant responsivity enhancement of the detector. The experimental results show a maximum voltage responsivity up to about 2000 V/W and 450 V/W, while the noise equivalence power is as low as 23 pW/Hz0.5 and 110 pW/Hz0.5 for the silicon antenna and metal antenna at the frequency of 220 GHz and 650 GHz, respectively. The presented dual-frequency detector can be easily implemented in a small size in favor of high-density array integration.

Characterization of the complete genome of euonymus yellow vein associated virus, a distinct member of the genus Potexvirus, family Alphaflexiviridae, isolated from Euonymus bungeanus Maxim in Liaoning, Northern China.

In August 2016, a yellow vein disease was observed on leaves of Euonymus bungeanus Maxim (Euonymus, Celastraceae) in Liaoning, China. Virions measuring 750 × 13 nm were observed in a sample from the diseased plant. A potexvirus was detected in the sample by small-RNA deep sequencing analysis and recovered by traditional cloning. The genome of this potexvirus consists of 7,279 nucleotides, excluding the poly(A) tail at the 3' end, and contains five open reading frames (ORFs). Based on the nucleotide and amino acid sequences of the coat protein gene, the virus shared the highest sequence similarity with white clover mosaic virus (WCMV, X16636) (40.1%) and clover yellow mosaic virus (ClYMV, D00485) (37.1%). Phylogenetic analysis showed that the virus clustered with potexviruses and is most closely related to strawberry mild yellow edge virus. These results indicate that this virus is a distinct member of the genus Potexvirus, for which the name euonymus yellow vein associated virus (EuYVAV) is proposed. To our knowledge, this is the first report of a potexvirus on E. bungeanus.

Efficacy, Safety, and Acceptability of Low-Dose Mifepristone and Self-Administered Misoprostol for Ultra-Early Medical Abortion: A Randomized Controlled Trial.

The aim of this study was to investigate the efficacy, safety, and acceptability of low-dose mifepristone combined with self-administered misoprostol for ultra-early medical abortion. A total of 744 women with ultra-early pregnancy (amenorrhea ≤35 days) who fulfilled the inclusion criteria were enrolled in the study. Equal numbers of participants were allocated randomly to the hospital administration and self-administration groups. All participants took 75 mg mifepristone at the initial visit and 400 µg oral misoprostol 24 hours later in the hospital or by self-administration. The primary end point was complete abortion. Secondary end points were rates of unscheduled reattendance, time required for and cost of hospital observation and follow-up, vaginal bleeding, adverse effects, menstrual disturbance in the posttreatment period, and satisfaction rating. No differences in the rates of complete abortion, unscheduled reattendance, vaginal bleeding, adverse effects, or return of posttreatment menstruation were observed. The time required for (and costs of) hospital observation and follow-up per participant was 557.82 minutes (and US$40.12) in the hospital administration group and 18.46 minutes (and US$1.96) in the self-administration group (both P < .001). Satisfaction rates were similar in both groups, but the rates of "very satisfied" responses (87.60% vs 25.41%) and follow-up compliance (loss to follow-up, 0.45% vs 7.70%) were higher in the self-administration group (both P < .001). Low-dose mifepristone combined with self-administered misoprostol for ultra-early pregnancy termination was as effective and safe as hospital administration, with greater acceptability and lower cost to the women.