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Surface plasmons in graphene provide a compelling strategy for advanced photonic technologies thanks to their tight confinement, fast response and tunability. Recent advances in the field of all-optical generation of graphene's plasmons in planar waveguides offer a promising method for high-speed signal processing in nanoscale integrated optoelectronic devices. Here, we use two counter propagating frequency combs with temporally synchronized pulses to demonstrate deterministic all-optical generation and electrical control of multiple plasmon polaritons, excited via difference frequency generation (DFG). Electrical tuning of a hybrid graphene-fibre device offers a precise control over the DFG phase-matching, leading to tunable responses of the graphene's plasmons at different frequencies across a broadband (0 ~ 50 THz) and provides a powerful tool for high-speed logic operations. Our results offer insights for plasmonics on hybrid photonic devices based on layered materials and pave the way to high-speed integrated optoelectronic computing circuits.

3D hosts are promising to extend the cycle life of lithium metal anodes but have rarely been implemented with lean electrolytes thus impacting the practical cell energy density. To overcome this challenge, a 3D host that is lightweight and easy to fabricate with optimum pore size that enables full utilization of its pore volume, essential for lean electrolyte operations, is reported. The host is fabricated by casting a VGCF (vapor-grown carbon fiber)-based slurry loaded with a sparingly soluble rubidium nitrate salt as an additive. The network of fibers generates uniform pores of ≈3 µm in diameter with a porosity of 80%, while the nitrate additive enhances lithiophilicity. This 3D host delivers an average coulombic efficiency of 99.36% at 1 mA cm-2 and 1 mAh cm-2 for over 860 cycles in half-cell tests. Full cells containing an anode with 1.35-fold excess lithium paired with LiNi0.8 Mn0.1 Co0.1 O2 (NMC811) cathodes exhibit capacity retention of 80% over 176 cycles at C/2 under a lean electrolyte condition of 3 g Ah-1 . This work provides a facile and scalable method to advance 3D lithium hosts closer to practical lithium-metal batteries.

BackgroundUveal melanoma (UVM) is a rare cancer that shows sex difference in incidence and survival, with little previous report for the underlying mechanism.MethodsThis study used the SEER data (1974-2016) for an age-dependent analysis on sex difference in UVM, and further used the TCGA-UVM genomics dataset for analyzing the differential gene expression profiles in tumors from men and women.ResultsOur results demonstrate a sex difference in older age (≥40 years) but not in younger patients, with men exhibiting a higher incidence rate than women. However, younger women have shown a continuous increasing trend since 1974. Examining the 11 major oncogenes and tumor suppressors in UVM revealed that EIF1AX showed a significant sex difference in mRNA accumulation and copy number variation, with female tumors expressing higher levels of EIF1AX and exhibiting more variations in copy numbers. EIF1AX mRNA levels were significantly inversely correlated with EIF1AX copy numbers in female tumors only, but not in male tumors. Differential gene expression analysis at the whole genomic level identified a set of 92 protein-coding and 16 RNA-coding genes which exhibited differential expression in men and women (fold of change cutoff at 1.7, adjusted p value < 0.05, FDR < 0.05). Network analysis showed significant difference in immune response and in disulfide bond formation, with EGR1/EGR2 and PDIA2 genes as regulators for immune response and disulfide bond formation, respectively. The melanocortin pathway which is linked to both melanin synthesis and obesity seems to be altered with unclear significance, as the sex difference in POMC, DCT/TYRP2, and MRAP2 was observed but with no clear direction.ConclusionThis study reveals possible mechanisms for the sex difference in tumorigenesis of UVM which has potentials for better understanding and prevention of UVM.

Lithium metal batteries (LMBs) hold the promise to pushing cell level energy densities beyond 300 Wh kg-1 while operating at ultra-low temperatures (< -30°C). Batteries capable of both charging and discharging at these temperature extremes are highly desirable due to their inherent reduction of external warming requirements. Here we demonstrate that the local solvation structure of the electrolyte defines the charge-transfer behavior at ultra-low temperature, which is crucial for achieving high Li metal coulombic efficiency (CE) and avoiding dendritic growth. These insights were applied to Li metal full cells, where a high-loading 3.5 mAh cm-2 sulfurized polyacrylonitrile (SPAN) cathode was paired with a one-fold excess Li metal anode. The cell retained 84 % and 76 % of its room temperature capacity when cycled at -40 and -60 °C, respectively, which presented stable performance over 50 cycles. This work provides design criteria for ultra-low temperature LMB electrolytes, and represents a defining step for the performance of low-temperature batteries.

ObjectiveTo analyze the effectiveness and safety of clinical use of different types of stem cells to provide evidence for governmental supervision of key issues in clinical utilization of stem cells.MethodsSix literature databases in China and abroad were searched for relevant literature published from January 2010 to July 2020， and a systematic review was conducted.ResultsThe study showed 72 studies concerning the effectiveness and safety of different types of stem cells in clinical utilization. Although clinical utilization of stem cells had some therapeutic effects for certain diseases， their long-term effect and safety need to be further evaluated， especially their potential risk of tumorigenicity.ConclusionTo protect the patients’ interest， physicians should fully weigh the benefits against the risks of clinical utilization of stem cells， and relevant governmental departments should strengthen supervision of ethics of clinical research and therapies involving stem cells as well as supervision of stem cell products.

Objective To evaluate the safety and efficacy of irreversible electroporation (IRE) combined with neoadjuvant chemotherapy in patients with locally advanced pancreatic cancer. Methods We searched PubMed, Embase, Cochrane Library, Web of Science, China Biomedical Literature Database, CNKI, Wanfang, and VIP databases for articles dated from the establishment of each database to March 2022. Meta-analysis was performed using RevMan5.4 software. Results A total of 3970 patients with locally advanced pancreatic cancer were enrolled in eight studies, including one randomized controlled trial, four retrospective studies, and three prospective studies. The patients were divided into the combined therapy group with 344 patients and the chemotherapy-only group with 3626 patients. Meta-analysis showed that the overall survival of patients in the combined therapy group was significantly higher than that in the chemotherapy-only group (OR=4.52; 95%CI: 2.63-7.77; P < 0.00001). However, no significant difference existed in the disease control rate between the combined therapy group and the chemotherapy-only group (OR=0.58; 95%CI: 0.02-18.74; P=0.76). Moreover, no significant difference existed in the disease progression between the two groups (OR=0.49; 95%CI: 0.23-1.02; P=0.06). The combination of neoadjuvant chemotherapy and IRE had no significant effect on the incidence of adverse reactions of gastrointestinal reaction (OR=0.37; 95%CI: 0.10-1.34; P=0.13) and bone marrow suppression (OR=0.61; 95%CI: 0.26-1.40; P=0.24). Conclusion IRE combined with neoadjuvant chemotherapy can remarkably improve the prognosis of patients with locally advanced pancreatic cancer, and significantly prolong the overall survival.

In the paper， national and international ethical requirements and supervision on stem cell research and clinical application were analyzed after literature review. It is suggested that the development of stem cell technology should be timely tracked， prospective ethical research related to stem cells should be enhanced， and that stem cell research and clinical translation should comply with relevant international ethical guidelines and national regulations in China. In addition， it is indicated that the oversight of stem cell products and their clinical use will be continuously improved in our country.

This paper studies the visual quality evaluation method along the tourist highway from the driver’s first perspective, selects five evaluation indexes from the aspects of driver’s driving reaction and physiological reaction, and establishes a “man-vehicle-road” visual quality evaluation method model of tourist highway. Through BIM + VR technology, the tourist highway scene is built for virtual driving experience and evaluation, and different landscape design schemes and dynamic effects of tourist highway are reproduced virtually. Combined with questionnaire survey and physiological data feedback, the tourist highway landscape is evaluated qualitatively and quantitatively, and a qualitative and quantitative evaluation method for the visual quality of tourist highway is put forward. It provides decision-making basis for local relevant departments to carry out landscape design quality evaluation along tourist highways, and realizes high-quality development of tourist highways.

A method of electro-thermal co-optimization design for the Gallium nitride (GaN) monolithic microwave integrated circuit (MMIC) power amplifier (PA) is introduced in this paper. Due to the self-heating effect of the GaN high electron mobility transistor (HEMT), it is necessary to pay attention to the influence of thermal resistance change on circuit performance when designing a high-power RF PA. For this purpose, a three-dimensional finite element analysis model of GaN multi-gate HEMT is developed. The thermal resistance and junction temperature of the device under a RF dynamic current are extracted by heat transfer simulation and can be substituted into the temperature node of the transistor model for PA circuit simulation design. To verify the proposed method, a Class AB MMIC PA was designed and tested using a 0.15-μm GaN-on-SiC process. Through the application of the above methods, the designed PA performance is optimized and achieves the performance of over 60% power-added efficiency (PAE) and 38 dBm saturation power (Psat) within a compact area of 1.6 mm × 2.2 mm. It is demonstrated that the proposed method can effectively improve the consistency of simulation results and measurement results, which can be a valuable reference for high-power MMIC PA design. [ABSTRACT FROM AUTHOR]

In this paper, a four-stage gallium nitride (GaN) low noise amplifier (LNA) using coupled-line (CL) feedback in a 0.15-μm GaN-on-SiC process is proposed. The electromagnetic coupling feedback between the drain and source of each transistor is employed to generate an additional signal path for neutralization, which enhances gain and improves stability performance. A series transmission line-capacitor-transmission line (TL-C-TL) network is introduced between stages of the LNA for wider band interstage matching. The measured results show that the designed LNA achieves a 3-dB bandwidth of 23.6 to 29.8 GHz, a peak gain of 23.7 dB at 25.8 GHz, and a minimum noise figure (NF) of 2.2 dB at 27.8 GHz. The output-referred 1-dB compression point (OP1dB) is 13 dBm. The total power consumption of the LNA is 200 mW. [ABSTRACT FROM AUTHOR]

A twice‐input variable‐resolution single‐side switching scheme without reset energy is proposed for successive approximation register (SAR) analogue‐to‐digital converters (ADCs). The proposed switching scheme is based on semi‐resting DAC technology to design a four‐array architecture capable of handling twice the swing of the signal input while reducing the capacitor array size. The technique of top‐plate sampling and monotonic shift is utilized so that no switching energy is generated for the first three comparisons. The proposed scheme utilizes full‐capacitor split, bridged switch, and C‐2C dummy capacitor technology, which reduces average switching energy consumption by 99.8% compared to conventional schemes and enables ADC variable resolution function, making the SAR ADC more suitable for IoT applications. [ABSTRACT FROM AUTHOR]

In this paper, a deep learning-based device modeling framework for design-technology co-optimization (DTCO) is proposed. A ResNet surrogate model is utilized as an alternative to traditional compact models, demonstrating high accuracy in both single-task (I–V or C–V) and multi-task (I–V and C–V) device modeling. Moreover, transfer learning is applied to the ResNet model, using the BSIM-CMG compact model for a 12 nm FinFET SPICE model as the pre-trained source. Through this approach, superior modeling accuracy and faster training speed are achieved compared to a ResNet surrogate model initialized with random weights, thereby meeting the rapid and efficient demands of the DTCO process. The effectiveness of the ResNet surrogate model in circuit simulation for 12 nm FinFET devices is demonstrated. [ABSTRACT FROM AUTHOR]

BackgroundAs an excellent nondestructive testing technology, cold neutron radiography is widely employed to image materials of interest in many basic and application research fields. One of key components of such device is the neutron sensitive scintillation screen. Normally, these screens are made up of scintillation or phosphor powder mixed with/without neutron sensing isotopes, such as 6LiF:ZnS(Ag) and Gd2O2S:Tb. Uniform scintillation screens are very difficult to make a trade-off between spatial resolution and neutron detection efficiency. Recently a new type of micro-structural scintillation screens has been proposed, which is expected to have higher spatial resolution while maintaining higher neutron detection efficiency. Following this idea, a scintillation screen has been proposed, developed, and studied by our group.PurposeThis study aims to develop a new type of scintillation screens based on a glass capillary array filled with scintillation powders to achieve high spatial resolution and neutron detection efficiency.MethodsFirst of all, a neutron sensing scintillation screen was made by filling very fine grinded Gd2O2S:Tb phosphor powder into glass capillary arrays. Three main steps, i.e. the phosphor powder grinding, the particle size screening, and the vacuum suction filtration process, were taken making such screens. Then, photographs of Gd2O2S:Tb phosphor before and after grinding were taken with a scanning electron microscope (SEM) to examine the filling efficiency of scintillation powder in the glass capillary arrays. Finally, experimental test of spatial resolution of such scintillation screens was carried out by using an optical system to read out the scintillation light emitted by the screen, and a Siemens Star neutron test target to characterize the screens' spatial resolution with cold neutrons.ResultsX-ray luminescence spectra show that the grinding process reduces the light yield of the phosphor. The filling efficiency of scintillation powder in the glass capillary arrays is up to 70%. The cold neutron imaging system with developed scintillation screen achieves spatial resolution of about 300 μm@CTF=3% by experimental test.ConclusionsAlthough the new neutron sensing scintillation screen is still under-developing and there are still some problems to be overcome, cold neutron imaging scintillation screen based on glass capillary array filled with Gd2O2S:Tb phosphor, proposed in this study, can be used to achieve high spatial resolution and neutron detection efficiency with advantages of low cost and simple fabrication process.