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Stimulated Brillouin scattering (SBS) in a high-Q resonator is capable for narrow-linewidth laser generation for various applications but is limited by on-resonance pump to SBS matching from single-longitudinal lasing. In this Letter, we present a narrow linewidth laser via SBS that is enhanced in a monolithic high-Q fiber resonator. The unique cross-polarization pump scheme based on fiber birefringence prevents high-order SBS and ensures single-frequency Brillouin lasing with high intracavity conversion efficiency. Fundamental linewidth of 50 Hz is achieved. Moreover, our scheme also allows precise characterization of Brillouin frequency shift and gain bandwidth of some nonlinear materials. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the second most fatal cancer. Many studies have shown that cancer stemness contributes to resistance to conventional chemotherapy and poor prognosis. However, the mechanisms involved in maintaining cancer stemness in CRC are still obscure and few clinical drugs were used to target cancer stemness. Previous studies had reported CD95 increases the stemness of cancer cells with long-term stimulation of exogenous agonist CD95 ligand (CD95L). However, the expression of CD95L is relative low in certain human tumor tissues. In this study, we found that CD95 was highly expressed in CRC cells, and in vitro it promoted the tumorsphere formation, chemotherapy resistance and in vivo tumor growth without stimulation of exogenous CD95L. Mechanistically, the bulk and single-cell RNA-sequencing results suggested that CD95 promotes stemness of CRC cells through upregulation of long non-coding RNAs metastasis-associated lung adenocarcinoma transcript 1 (lncRNA MALAT1). MALAT1 knockdown inhibited CD95-induced tumorsphere formation and chemotherapy resistance. In summary, our findings reveal that CD95 has the capability to modulate cancer stemness via the action of the lncRNA MALAT1. Targeting CD95 may be a promising strategy to inhibit cancer stemness in CRC. [ABSTRACT FROM AUTHOR]

We demonstrate a broadband optical parametric oscillation, using a sheet cavity, via cavity phase-matching. A 21.2 THz broad comb-like spectrum is achieved, with a uniform line spacing of 133.0 GHz, despite a relatively large dispersion of 275.4 fs2/mm around 1064 nm. With 22.6% high slope efficiency, and 14.9 kW peak power handling, this sheet optical parametric oscillator can be further developed for χ(2) comb. [ABSTRACT FROM AUTHOR]

Mid-infrared (MIR) radiation is essential for remote gas sensing, ranging, and lidar applications, where high pulse energy and narrow linewidth are the keys to the high sensitivity over long distance. However, complex optical and electronic locking schemes are normally required to achieve both features at the same time. Here, we demonstrate pulse-pumped single-longitudinal-mode (SLM) MIR generation using a microresonator seed in the form of a sheet optical parametric oscillator (SOPO). The SOPO features a sub-coherence-length thickness of 400 µm, which enables SLM and high-energy oscillation using cavity phase matching. Its output around 1.55 µm is seeded into an optical parametric amplifier and locks the MIR output in SLM at 3.38 µm. In a simple and compact setup, up to 21% conversion efficiency and 22% slope efficiency are measured with a MIR output energy of 54 µJ. This SLM MIR source with the SOPO seed greatly reduces the system size and is compatible for further integration for field-deployable devices and thus has broad applications in the field of remote gas sensing. [ABSTRACT FROM AUTHOR]

A self-injection locking scheme has the potential to narrow the linewidth of lasers in a compact setup. Here, we report a narrow linewidth laser source near 1 μm by the self-injection locking scheme using a Fabry–Pérot (FP) hollow resonator with a high-quality factor (Q > 108). The measured fundamental linewidth of the laser is 41 Hz, and a coarse tuning range over 5.5 nm is achieved by changing the driving current of the laser source. Meanwhile, a fine-tuning range of 373 MHz is achieved without mode hops by changing the voltage applied to the PZT on the resonator. More importantly, benefiting from the low thermal refractive noise and low thermal expansion of the FP hollow resonator, the beat-note linewidth and the frequency Allan deviation are measured to be 510.3 Hz in and 10−11 (1 s of averaging time), respectively, by using a fully stabilized frequency comb as a reference. Such a high-performance laser is fully integrated with a palm-sized package (52.3 ml) for field-deployable applications. [ABSTRACT FROM AUTHOR]

In terrestrial plants, stomata in the leaf epidermis formed by guard cells are the major pathways for gas exchange. However, opened stomata also provide a major channel for pathogen entry. At the pre‐invasive stage, plants actively close stomata to prevent pathogen attack, which is termed stomatal immunity, and plant hormones are involved in this process. Here, we summarize recent advances in the role of abscisic acid (ABA) in promoting stomatal immunity to prevent pathogen entry. Additionally, salicylic acid shares common downstream elements with ABA to promote stomatal immunity, whereas reactive oxygen species and Ca2+ act as critical signals to cross‐talk with ABA signalling to regulate stomatal movement, and they also enhance the effect of ABA in stomatal immunity. On the other hand, at the post‐invasive stage, closed stomata create a water‐soaked environment that allows pathogen multiplication, and ABA signalling is hijacked by pathogens to reduce stomatal aperture. Here, we propose a model of dual roles of ABA‐mediated stomatal closure during plant‐pathogen interaction and offer emerging consequences and questions for ABA‐mediated stomatal immunity. [ABSTRACT FROM AUTHOR]

Aims Accumulating evidence supports the indispensable role of protein arginine methyltransferase 5 (PRMT5) in the pathological progression of several human cancers. As an important enzyme-regulating protein methylation, how PRMT5 participates in vascular remodelling remains unknown. The aim of this study was to investigate the role and underlying mechanism of PRMT5 in neointimal formation and to evaluate its potential as an effective therapeutic target for the condition. Methods and results Aberrant PRMT5 overexpression was positively correlated with clinical carotid arterial stenosis. Vascular smooth muscle cell (SMC)-specific PRMT5 knockout inhibited intimal hyperplasia with an enhanced expression of contractile markers in mice. Conversely, PRMT5 overexpression inhibited SMC contractile markers and promoted intimal hyperplasia. Furthermore, we showed that PRMT5 promoted SMC phenotypic switching by stabilizing Kruppel-like factor 4 (KLF4). Mechanistically, PRMT5-mediated KLF4 methylation inhibited ubiquitin-dependent proteolysis of KLF4, leading to a disruption of myocardin (MYOCD)–serum response factor (SRF) interaction and MYOCD–SRF-mediated the transcription of SMC contractile markers. Conclusion Our data demonstrated that PRMT5 critically mediated vascular remodelling by promoting KLF4-mediated SMC phenotypic conversion and consequently the progression of intimal hyperplasia. Therefore, PRMT5 may represent a potential therapeutic target for intimal hyperplasia–associated vascular diseases. [ABSTRACT FROM AUTHOR]

For graphene films, the change of crystal structure induced by ion bombardment as well as the doping and strain generated in thermal annealing process is addressed in this work. Experimental results show that both the structure and number of defects for graphene depends strongly on the ion dose. Furthermore, it is found that the structure defects caused by ion bombardment in graphene can be healed and the graphene samples are all doped in subsequent thermal annealing. The frequency shift of G and 2D peaks in Raman spectra reveals that compressive strain in graphene results from the thermal annealing treatment and the occurrence of strain is influenced by the thermal annealing and defects in graphene. For graphene, since defects and thermal annealing are unavoidable for the fabrication of graphene-based devices, the systematical investigation on these two aspects in this work is, therefore, of great importance and significance. [ABSTRACT FROM AUTHOR]

The effect of ion-induced defects on graphene was studied to investigate the contact resistance of 40 nm palladium (Pd) contacting on graphene. The defect development was considered and analyzed by irradiating boron (B), carbon (C), nitrogen (N2), and argon (Ar) ions on as-transferred graphene before metallization. The bombardment energy was set at 1.5 keV and ion dose at 1 × 1014 ions/cm2. The defect yields under different ion irradiation conditions were examined by Raman spectroscopy. Although, dissolution process occurs spontaneously upon metal deposition, chemical reaction between metal and graphene is more pronounced at higher temperatures. The rapid thermal annealing (RTA) treatment was performed to improve the Pd/graphene contact after annealing at 450 °C, 500 °C, 550 °C, and 600 °C. The lowest contact resistance of 95.2 Ω-µm was achieved at 550 °C RTA with Ar ion irradiation. We have proved that ion irradiation significantly enhance the Pd/graphene contact instead of pd/pristine graphene contact. Therefore, in view of the contention of results ion induced defects before metallization plus the RTA served an excellent purpose to reduce the contact resistance. [ABSTRACT FROM AUTHOR]

Periodically poled lithium niobate on insulator (PPLNOI) offers an admirably promising platform for the advancement of nonlinear photonic integrated circuits (PICs). In this context, domain inversion engineering emerges as a key process to achieve efficient nonlinear conversion. However, periodic poling processing of thin-film lithium niobate has only been realized on the chip level, which significantly limits its applications in large-scale nonlinear photonic systems that necessitate the integration of multiple nonlinear components on a single chip with uniform performances. Here, we demonstrate a wafer-scale periodic poling technique on a 4-inch LNOI wafer with high fidelity. The reversal lengths span from 0.5 to 10.17 mm, encompassing an area of ~1 cm2 with periods ranging from 4.38 to 5.51 μm. Efficient poling was achieved with a single manipulation, benefiting from the targeted grouped electrode pads and adaptable comb line widths in our experiment. As a result, domain inversion is ultimately implemented across the entire wafer with a 100% success rate and 98% high-quality rate on average, showcasing high throughput and stability, which is fundamentally scalable and highly cost-effective in contrast to traditional size-restricted chiplet-level poling. Our study holds significant promise to dramatically promote ultra-high performance to a broad spectrum of applications, including optical communications, photonic neural networks, and quantum photonics. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is a functional impairment of the spinal cord caused by external forces, accompanied by limb movement disorders and permanent paralysis, which seriously lowers the life quality of SCI patients. Secondary injury caused by inflammation attenuated the therapeutic effects of SCI. Therefore, the exploration of biomarkers associated with the inflammatory response following SCI might provide novel therapy strategy against SCI.SCI rat model was established as previously reported and evaluated by BBB score. The expression of microRNA-24-3p (miR-24-3p) and MAPK-activated protein kinase 2 (MK2) in spinal cord tissues of SCI rats and HAPI cells was analyzed by qRT-PCR. Protein expression of MK2, ionized calcium-binding adapter molecule-1 (Iba-1), tumor necrosis factor-alpha (TNF-α), and interleukin-1β (IL-1β) was assessed by western blot assay. The release of inflammatory cytokines TNF-α and IL-1β was measured by enzyme-linked immunosorbent assay (ELISA). The interaction between miR-24-3p and MK2 was examined by the luciferase reporter system. Basso-Beattie-Bresnahan (BBB) score dramatically reduced in rats following SCI compared with sham rats. Moreover, the expression of miR-24-3p was down-regulated, while MK2 was up-regulated in the spinal cord tissues of SCI rats and LPS-induced microglia cells compared with the corresponding control group. Luciferase reporter system confirmed the interaction between miR-24-3p and MK2. In addition, miR-24-3p upregulation or MK2 knockdown attenuated LPS induced activation of microglial cells and expression of inflammatory cytokine TNF-α and IL-1β. Besides, we discovered that miR-24-3p regulated inflammation of highly aggressively proliferating immortalized (HAPI) cells by targeting MK2.In our study, we clarified that miR-24-3p repressed inflammation of microglia cells following SCI by regulating MK2, thereby providing promising biomarkers for SCI therapy. [ABSTRACT FROM AUTHOR]

The degradation of InSe film and its impact on field effect transistors are investigated. After the exposure to atmospheric environment, 2D InSe flakes produce irreversible degradation that cannot be stopped by the passivation layer of h-BN, causing a rapid decrease for InSe FETs performance, which is attributed to the large number of traps formed by the oxidation of 2D InSe and adsorption to impurities. The residual photoresist in lithography can cause unwanted doping to the material and reduce the performance of the device. To avoid contamination, a high-performance InSe FET is achieved by a using hard shadow mask instead of the lithography process. The high-quality channel surface is manifested by the hysteresis of the transfer characteristic curve. The hysteresis of InSe FET is less than 0.1 V at Vd of 0.2, 0.5, and 1 V. And a high on/off ratio of 1.25 × 108 is achieved, as well relative high Ion of 1.98 × 10−4 A and low SS of 70.4 mV/dec at Vd = 1 V are obtained, demonstrating the potential for InSe high-performance logic device. [ABSTRACT FROM AUTHOR]

A multivalued logic (MVL) device can achieve greater data density with a smaller footprint than a traditional binary logic device. In this study, a ternary logic inverter based on negative capacitance FETs (NCFETs) without additional footprints has been realized. By enhancing the amplification in surface potential owing to the utilization of the negative capacitance, the third intermediate state can be successfully obtained at VDD/2 in the conventional binary CMOS inverter. The third intermediate state arises due to no-saturation effect of drain current, and the noise margin of the third intermediate state (NMM) can be optimized by changing ferroelectric thickness or annealing temperature of ferroelectric material. The influence of remnant polarization (Pr) and coercive electric (EC) variation on the ternary logic inverter was investigated based on experimental data. Moreover, a ternary logic 8T SRAM with transmission gate logic (TGL) was proposed, and the results show that the proposed 8T SRAM cell exhibits nondestructive read and reliable write operations for all three states. [ABSTRACT FROM AUTHOR]

The negative-capacitance field-effect transistor (NCFET) is an emerging steep switching device that utilizes the negative capacitance of the ferroelectric layer to induce voltage amplification in the gate stack. In this study, an NCFET was fabricated by using a replacement metal gate process, which can avoid the influence of high temperature processes on ferroelectric film. The different sub-threshold slope (SS) characteristics of forward gate voltage sweep and reverse gate voltage sweep were investigated. The results show that the different SS characteristics may originate from asymmetrical polarization–voltage (P–V) hysteresis loops of metal–ferroelectric–insulator–silicon capacitance in the NCFET. Moreover, the influences of Hf/Zr ratio, annealing temperature and capacitance size on ferroelectric characteristics were investigated. The experimental results show that there is an optimal Hf/Zr ratio and annealing temperature that maximizes the residual polarization (Pr). For ferroelectric field-effect transistor (FeFET) memory design, the largest Pr should be chosen to increase retention time. For ferroelectric NCFET logic design, the negative capacitance can be adjusted by changing the Hf/Zr ratio and annealing temperature to achieve better capacitance matching between positive capacitance and negative capacitance. It is expected that experimental results may provide some guidance for the design and performance enhancement of FeFETs and NCFETs. [ABSTRACT FROM AUTHOR]

Enterovirus71(EV71), the etiological agent of hand-foot-and-mouth disease, has increasingly become a public health challenge around the world. Type I interferons (IFNs) are an important family of cytokines that regulate innate and adaptive immune responses to pathogens.These pathways are tightly regulated by the host to prevent an inappropriate cellular response, but viruses can modulate these pathways to proliferate and spread. In this study, we demonstrated that EV71 evades the immune surveillance system to proliferate by activating microRNA-21. We demonstrated that EV71 infection upregulates miR-21, which in turn suppresses EV71-triggered type I IFN production, thus promoting EV71 replication. Furthermore, we demonstrated that miR-21 targets the myeloid differentiation factor 88(MyD88) and interleukin-1 receptor-associated kinase 1(IRAK1), which are involved in EV71-induced type I IFN production. [ABSTRACT FROM AUTHOR]

• Created a new type of embedded cooling modules for multi-chip electronic devices. • The module can be reconfigured, and chips can be replaced multiple times. • Tested a 70 × 88 × 9 mm3 cooling module for a 3 × 3 array of chips. • Demonstrated successful thermal management of multi-chip electronic devices. • Can be useful for high-performance processors and DC/DC power converters. Multi-chip thermal management technology is facing new challenges for improving system performance with the increasing use of multi-chip strategies in electronic systems. In this study, an embedded cooling method with configurability and replaceability for multi-chip electronic devices was demonstrated. A cooling module with the size of 70 × 88 × 9 mm3 for a 3 × 3 chip array verified the feasibility. The experimental results showed that each chip was cooled independently with no thermal coupling between each other, the maximum temperature of the array less than 85.81 ℃ and the temperature uniformity was 0.0728 (coefficient of variation) at 600 W/cm2 and 500 mL/min. Under the same conditions, the cooling effect of chips in the array was not affected by arrangements, where the differences in pressure drops and temperature uniformity were less than 4% and 0.0276, respectively. The heat dissipation effect of the chips in the module remained unchanged after repeated assembly, which proves the replaceability of the chips into the module. Therefore, this configurable and replaceable cooling method for multi-chip electronic devices is promising for high-performance processors and power converters. [ABSTRACT FROM AUTHOR]

Summary: Strigolactones (SLs), a class of the most recently identified terpenoid phytohormones, play essential roles in plant development, specifically in suppressing shoot branching. MAX2, a subunit of an SCF E3 ligase and a positive regulator that inhibits shoot branching, is likely a key SL signaling component. Here, we provide genetic and biochemical evidence to demonstrate that BES1 interacts with MAX2 and acts as its substrate to regulate SL-responsive gene expression. Additional AtD14, a putative receptor of SLs, can promote BES1 degradation. Knockdown of BES1 and its homologs dramatically suppressed the branching phenotype of max2-1 mutant. These results portray an SL signaling cascade from the putative receptor to downstream transcription factors. In addition, we demonstrate that the SL and brassinosteroid (BR) signaling pathways distinctly regulate the same transcription factor, BES1, to control specific developmental processes. [Copyright &y& Elsevier]

In this study, negative DIBL (NDIBL) due to negative capacitance is used to improve MOSFETs and Complementary Metal-Oxide-Semiconductor Transistor (CMOS) circuits by employing custom-built Simulation Program with Integrated Circuit Emphasis (SPICE) model. A multi-threshold technique was proposed by using NDIBL effect, and it can be manufactured by simple manufacturing process without increasing footprint of transistor. The influence of the negative DIBL effect of a negative capacitance field-effect-transistor (NCFET) on transistor effective drive current (I eff) and CMOS circuit performance were analyzed. The results shown that increasing NDIBL effect increased I eff by ~12%. A 7-stage ring oscillator (RO) was simulated to analyze the CMOS circuit energy-delay, and it shown that significant delay reduction, at iso-energy and iso-area, can be achieved owing to NDIBL effect of NCFET. A 6T Static Random-Access Memory (SRAM) cell was investigated, and enhanced hold and read static noise margins (SNM) are achieved owing to NDIBL effect. Moreover, several methods of increasing NDIBL effect were proposed. [ABSTRACT FROM AUTHOR]

The applications of a boron-doped diamond (BDD) used in electrode application for toxic and refractory organic degradation have attracted much attention, and its efficiency is considered to be an important factor for its practical application. In this study, BDD thin films were prepared on Ti plates by double bias-assisted hot filament chemical vapor deposition (HFCVD) technique. A reactive ion etching process was introduced by a positive grid bias and a negative substrate bias which can generate an electric field in HFCVD system. Then a novel structure of BDD electrode with nanocone arrays was successfully etched from a flat diamond thin film by this system. The addition of the bias greatly improved the etching efficiency and promoted the formation of nanocones structures. The cyclic voltammograms (CV) test showed nanostructured BDD (NBDD) electrodes had excellent electrochemical performance almost the same as that of the electrodes with untreated surfaces. It had a large effective electroactive surface area (EASA), which was 31.0% greater than the unetched electrode. As a result, the NBDD electrode exhibited improved electrocatalytic performance as compared with the untreated one, i.e., an about 24.3% increase of chemical oxygen demand (COD) removal efficiency. Among them, the superiority of NBDD electrode was obvious in the initial stage due to its highest concentration in the initial stage. In addition, the NBDD electrode achieved higher average current efficiency (ACE) as compared with the untreated one. Unlabelled Image • The BDD nanostructure was prepared by double bias-assisted HFCVD system. • The NBDD films were used as electrodes for wastewater treatment. • The EASA of the NBDD electrodes was increased. • The COD removal rate and ACE of NBDD electrodes were improved. [ABSTRACT FROM AUTHOR]

With the development of new designs and materials for nano-scale transistors, vertical Gate-All-Around Field Effect Transistors (vGAAFETs) with germanium as channel materials have emerged as excellent choices. The driving forces for this choice are the full control of the short channel effect and the high carrier mobility in the channel region. In this work, a novel process to form the structure for a VGAA transistor with a Ge channel is presented. The structure consists of multilayers of Si0.2Ge0.8/Ge grown on a Ge buffer layer grown by the reduced pressure chemical vapor deposition technique. The Ge buffer layer growth consists of low-temperature growth at 400 °C and high-temperature growth at 650 °C. The impact of the epitaxial quality of the Ge buffer on the defect density in the Si0.2Ge0.8/Ge stack has been studied. In this part, different thicknesses (0.6, 1.2 and 2.0 µm) of the Ge buffer on the quality of the Si0.2Ge0.8/Ge stack structure have been investigated. The thicker Ge buffer layer can improve surface roughness. A high-quality and atomically smooth surface with RMS 0.73 nm of the Si0.2Ge0.8/Ge stack structure can be successfully realized on the 1.2 µm Ge buffer layer. After the epitaxy step, the multilayer is vertically dry-etched to form a fin where the Ge channel is selectively released to SiGe by using wet-etching in HNO3 and H2O2 solution at room temperature. It has been found that the solution concentration has a great effect on the etch rate. The relative etching depth of Ge is linearly dependent on the etching time in H2O2 solution. The results of this study emphasize the selective etching of germanium and provide the experimental basis for the release of germanium channels in the future. [ABSTRACT FROM AUTHOR]