Integrated and DC-powered superconducting microcomb.

Frequency combs, specialized laser sources emitting multiple equidistant frequency lines, have revolutionized science and technology with unprecedented precision and versatility. Recently, integrated frequency combs are emerging as scalable solutions for on-chip photonics. Here, we demonstrate a fully integrated superconducting microcomb that is easy to manufacture, simple to operate, and consumes ultra-low power. Our turnkey apparatus comprises a basic nonlinear superconducting device, a Josephson junction, directly coupled to a superconducting microstrip resonator. We showcase coherent comb generation through self-started mode-locking. Therefore, comb emission is initiated solely by activating a DC bias source, with power consumption as low as tens of picowatts. The resulting comb spectrum resides in the microwave domain and spans multiple octaves. The linewidths of all comb lines can be narrowed down to 1 Hz through a unique coherent injection-locking technique. Our work represents a critical step towards fully integrated microwave photonics and offers the potential for integrated quantum processors.

Designing Different Heterometallic Organic Frameworks by Heteroatom and Second Metal Doping Strategies for the Electrocatalytic Oxygen Evolution Reaction.

Metal-organic frameworks (MOFs) are considered one of the most significant electrocatalysts for the sluggish oxygen evolution reaction (OER). Hence, a series of novel N,S-codoped Ni-based heterometallic organic framework (HMOF) (NiM-bptz-HMOF, M = Co, Zn, and Mn; bptz = 2,5-bis((3-pyridyl)methylthio)thiadiazole) precatalysts are constructed by the heteroatom and second metal doping strategies. The effective combination of the two strategies promotes electronic conductivity and optimizes the electronic structure of the metal. By regulation of the type and proportion of metal ions, the electrochemical performance of the OER can be improved. Among them, the optimized Ni6Zn1-bptz-HMOF precatalyst exhibits the best performance with an overpotential of 268 mV at 10 mA cm-2 and a small Tafel slope of 72.5 mV dec-1. This work presents a novel strategy for the design of modest heteroatom-doped OER catalysts.

Unconventional Superconducting Diode Effects via Antisymmetry and Antisymmetry Breaking.

Symmetry breaking plays a pivotal role in unlocking intriguing properties and functionalities in material systems. For example, the breaking of spatial and temporal symmetries leads to a fascinating phenomenon: the superconducting diode effect. However, generating and precisely controlling the superconducting diode effect pose significant challenges. Here, we take a novel route with the deliberate manipulation of magnetic charge potentials to realize unconventional superconducting flux-quantum diode effects. We achieve this through suitably tailored nanoengineered arrays of nanobar magnets on top of a superconducting thin film. We demonstrate the vital roles of inversion antisymmetry and its breaking in evoking unconventional superconducting effects, namely a magnetically symmetric diode effect and an odd-parity magnetotransport effect. These effects are nonvolatilely controllable through in situ magnetization switching of the nanobar magnets. Our findings promote the use of antisymmetry (breaking) for initiating unconventional superconducting properties, paving the way for exciting prospects and innovative functionalities in superconducting electronics.

Linear and phase controllable terahertz frequency conversion via ultrafast breaking the bond of a meta-molecule.

The metasurface platform with time-varying characteristics has emerged as a promising avenue for exploring exotic physics associated with Floquet materials and for designing photonic devices like linear frequency converters. However, the limited availability of materials with ultrafast responses hinders their applications in the terahertz range. Here we present a time-varying metasurface comprising an array of superconductor-metal hybrid meta-molecules. Each meta-molecule consists of two meta-atoms that are "bonded" together by double superconducting microbridges. Through experimental investigations, we demonstrate high-efficiency linear terahertz frequency conversion by rapidly breaking the bond using a coherent ultrashort terahertz pump pulse. The frequency and relative phase of the converted wave exhibit strong dependence on the pump-probe delay, indicating phase controllable wave conversion. The dynamics of the meta-molecules during the frequency conversion process are comprehensively understood using a time-varying coupled mode model. This research not only opens up new possibilities for developing innovative terahertz sources but also provides opportunities for exploring topological dynamics and Floquet physics within metasurfaces.

A compact multi-pixel superconducting nanowire single-photon detector array supporting gigabit space-to-ground communications.

Classical and quantum space-to-ground communications necessitate highly sensitive receivers capable of extracting information from modulated photons to extend the communication distance from near-earth orbits to deep space explorations. To achieve gigabit data rates while mitigating strong background noise photons and beam drift in a highly attenuated free-space channel, a comprehensive design of a multi-functional detector is indispensable. In this study, we present an innovative compact multi-pixel superconducting nanowire single-photon detector array that integrates near-unity detection efficiency (91.6%), high photon counting rate (1.61 Gcps), large dynamic range for resolving different photon numbers (1-24), and four-quadrant position sensing function all within one device. Furthermore, we have constructed a communication testbed to validate the advantages offered by such an architecture. Through 8-PPM (pulse position modulation) format communication experiments, we have achieved an impressive maximum data rate of 1.5 Gbps, demonstrating sensitivities surpassing previous benchmarks at respective speeds. By incorporating photon number information into error correction codes, the receiver can tolerate maximum background noise levels equivalent to 0.8 photons/slot at a data rate of 120 Mbps-showcasing a great potential for daylight operation scenarios. Additionally, preliminary beam tracking tests were conducted through open-loop scanning techniques, which revealed clear quantitative dependence indicating sensitivity variations based on beam location. Based on the device characterizations and communication results, we anticipate that this device architecture, along with its corresponding signal processing and coding techniques, will be applicable in future space-to-ground communication tasks.

High-timing-precision detection of single X-ray photons by superconducting nanowires.

Precisely acquiring the timing information of individual X-ray photons is important in both fundamental research and practical applications. The timing precision of commonly used X-ray single-photon detectors remains in the range of one hundred picoseconds to microseconds. In this work, we report on high-timing-precision detection of single X-ray photons through the fast transition to the normal state from the superconductive state of superconducting nanowires. We successfully demonstrate a free-running X-ray single-photon detector with a timing resolution of 20.1 ps made of 100-nm-thick niobium nitride film with an active area of 50 µm by 50 µm. By using a repeated differential timing measurement on two adjacent X-ray single-photon detectors, we demonstrate a precision of 0.87 ps in the arrival-time difference of X-ray photon measurements. Therefore, our work significantly enhances the timing precision in X-ray photon counting, opening a new niche for ultrafast X-ray photonics and many associated applications.

Cyp3A4 *1G polymorphism is associated with alcohol drinking: A 5-year retrospective single centered population-based study in China.

INTRODUCTION: We investigated the epidemiology of Cytochrome P450 (CYP) 3A4 genotype and the relationship between CYP3A4 genotype and alcohol drinking habits. MATERIALS AND METHODS: A single-centered retrospective study was conducted on 630 patients who underwent CYP3A4*1G genetic testing. Their relevant information on epidemiology and etiology was collected. Laboratory testing, including CYP3A4*1G genotype, liver function tests, and serum lipid measurements were performed. Bi-variate logistic regressions were used to examine the relationship between variables. The relationship between alcohol drinking and CYP3A4*1G genotype was estimated. Demographic and clinical features were analyzed. Participants with drinking history were divided into non-heavy drinking and heavy drinking groups. Liver function and dyslipidemia of participants with drinking histories were compared between CYP3A4*1G mutation (GA+AA) and wild-type (GG) groups. RESULTS: Participants with CYP3A4*1G mutation(GA+AA) had an increased adjusted odds ratio (AOR) of 2.56 (95% CI, 1.4-4.65; P = 0.00) for alcohol abuse when compared with participants without CYP3A4 mutation (GG). In the subgroup of participants with alcohol abuse, there are no significant differences in liver injury levels and serum lipid levels between CYP3A4*1G mutant and wild-type groups. Patients with CYP3A4*1G mutation had an increased AOR of cardiac-vascular diseases and malignant diseases compared with patients without CYP3A4*1G mutation. The epidemiology had no difference between GA and AA group. CONCLUSION: The study indicated that there was association between alcohol drinking and CYP3A4*1G genetic mutation. In the subgroup of participants with alcohol abuse, there are no significant differences in liver injury and dyslipidemia between CYP3A4*1G mutant and wild-type groups. CYP3A4*1G mutation was also related to cardiac-vascular diseases and malignant diseases.

Increased age, bilirubin, international normalized ratio, and creatinine score to triglyceride ratio are associated with alcohol-associated primary liver carcinoma: a single-centered retrospective study.

BACKGROUND: This study analyzed the clinical features and biomarkers of alcohol-associated liver disease (ALD) to investigate the diagnostic value of age, bilirubin, international normalized ratio (INR), and creatinine (ABIC) score to triglyceride (TG) ratio (ABIC/TG) in ALD-associated primary liver carcinoma (PLC). MATERIALS AND METHODS: Data were collected from 410 participants with ALD, and the epidemiological and clinical records of 266 participants were analyzed. Participants were divided into ALD-without-PLC and ALD-associated-PLC groups. Relationships between clinical characteristics, biomarkers and ALD-associated PLC were estimated. Serum lipid levels and liver function were compared between ALD patients without PLC and patients with ALD-associated PLC. Scoring systems were calculated to investigate ALD severity. The robustness of the relationship was analyzed by the receiver operating characteristic (ROC) curve. RESULTS: Age and dyslipidemia were more strongly associated with ALD-associated PLC than with ALD-without PLC, with AORs of 2.39 and 0.25, respectively, with P less than 0.05. Drinking time and average daily intake, ABIC score, and ABIC/TG ratio were significantly higher in the ALD-associated-PLC group than in the ALD-without-PLC group. The AUC for the ABIC/TG ratio predicting the incidence of PLC was 0.80 (P < 0.01), which was higher than that of the ABIC and TG scores alone; additionally, the specificity and Youden index for the ABIC/TG ratio were also higher, and the cutoff value was 6.99. CONCLUSIONS: In ALD patients, age, drinking time, and average daily intake were risk factors for PLC. Drinking time, average daily intake, TG and ABIC score have diagnostic value for ALD-associated PLC. The ABIC/TG ratio had a higher AUC value and Youden index than the ABIC score and TG level.

Image distortion by ambiguous multiple-photon detections in a superconducting nanowire single-photon imager and the correction method.

Scaling up superconducting nanowire single-photon detectors (SNSPDs) into a large array for imaging applications is the current pursuit. Although various readout architectures have been proposed, they cannot resolve multiple-photon detections (MPDs) currently, which limits the operation of the SNSPD arrays at high photon flux. In this study, we focused on the readout ambiguity of a superconducting nanowire single-photon imager applying time-of-flight multiplexing readout. The results showed that image distortion depended on both the incident photon flux and the imaging object. By extracting multiple-photon detections on idle pixels, which were virtual because of the incorrect mapping from the ambiguous readout, a correction method was proposed. An improvement factor of 1.3~9.3 at a photon flux of µ = 5 photon/pulse was obtained, which indicated that joint development of the pixel design and restoration algorithm could compensate for the readout ambiguity and increase the dynamic range.

Topotactic fabrication of transition metal dichalcogenide superconducting nanocircuits.

Superconducting nanocircuits, which are usually fabricated from superconductor films, are the core of superconducting electronic devices. While emerging transition-metal dichalcogenide superconductors (TMDSCs) with exotic properties show promise for exploiting new superconducting mechanisms and applications, their environmental instability leads to a substantial challenge for the nondestructive preparation of TMDSC nanocircuits. Here, we report a universal strategy to fabricate TMDSC nanopatterns via a topotactic conversion method using prepatterned metals as precursors. Typically, robust NbSe2 meandering nanowires can be controllably manufactured on a wafer scale, by which a superconducting nanowire circuit is principally demonstrated toward potential single photon detection. Moreover, versatile superconducting nanocircuits, e.g., periodical circle/triangle hole arrays and spiral nanowires, can be prepared with selected TMD materials (NbS2, TiSe2, or MoTe2). This work provides a generic approach for fabricating nondestructive TMDSC nanocircuits with precise control, which paves the way for the application of TMDSCs in future electronics.

Modeling of a multireflector terahertz imaging system using a geometrical optics model based on angular spectrum theory.

We propose a simulation method for a multireflector terahertz imaging system. The description and verification of the method are based on an existing active bifocal terahertz imaging system at 0.22 THz. Using the phase conversion factor and angular spectrum propagation, the computation of the incident and received fields requires only a simple matrix operation. The phase angle is used to calculate the ray tracking direction, and the total optical path is used to calculate the scattering field of defective foams. Compared with the measurements and simulations of aluminum disks and defective foams, the validity of the simulation method is confirmed in the field of view of 50 cm × 90 cm at 8 m. This work aims to develop better imaging systems by predicting their imaging behavior for different targets before manufacturing.

PRMT1 inhibition promotes ferroptosis sensitivity via ACSL1 upregulation in acute myeloid leukemia.

Acute myeloid leukemia (AML) is a hematological malignancy with an alarming mortality rate. The development of novel therapeutic targets or drugs for AML is urgently needed. Ferroptosis is a form of regulated cell death driven by iron-dependent lipid peroxidation. Recently, ferroptosis has emerged as a novel method for targeting cancer, including AML. Epigenetic dysregulation is a hallmark of AML, and a growing body of evidence suggests that ferroptosis is subject to epigenetic regulation. Here, we identified protein arginine methyltransferase 1 (PRMT1) as a ferroptosis regulator in AML. The type I PRMT inhibitor GSK3368715 promoted ferroptosis sensitivity in vitro and in vivo. Moreover, PRMT1-knockout cells exhibited significantly increased sensitivity to ferroptosis, suggesting that PRMT1 is the primary target of GSK3368715 in AML. Mechanistically, both GSK3368715 and PRMT1 knockout upregulated acyl-CoA synthetase long-chain family member 1 (ACSL1), which acts as a ferroptosis promoter by increasing lipid peroxidation. Knockout ACSL1 reduced the ferroptosis sensitivity of AML cells following GSK3368715 treatment. Additionally, the GSK3368715 treatment reduced the abundance of H4R3me2a, the main histone methylation modification mediated by PRMT1, in both genome-wide and ACSL1 promoter regions. Overall, our results demonstrated a previously unknown role of the PRMT1/ACSL1 axis in ferroptosis and suggested the potential value and applications of the combination of PRMT1 inhibitor and ferroptosis inducers in AML treatment.

Increased TG to HDL-C ratio is associated with severity of drug-induced liver injury.

We investigated the relationship between dyslipidemia and drug-induced liver injury (DILI), especially the level of triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-C) in severe DILI. In this single-centered retrospective study, of 326 patients with DILI, 221 patients were analyzed. Control groups include medication using group and acute hepatitis B group. The relationship between dyslipidemia and DILI was estimated. Demographic and clinical features were analyzed. Dyslipidemia and TG/HDL-C ratios were compared between DILI and control groups, DILI mild group and severe group. The area under the receiver-operating characteristic curve (AUC) was used to evaluate the credibility of the relationship and to find cut-off points. Dyslipidemia is related to DILI when compared with medication using control group (AOR 4.60; 95% CI 2.81-7.54; P < 0.01) and compared with acute hepatitis B group (AOR 2.12; 95% CI 1.37-3.29; P < 0.01). Dyslipidemia is associated with the severity of DILI (AOR 25.78; 95% CI 7.63-87.1; P < 0.01). TG/HDL-C ratio is higher in DILI group than that of medication using control group, also higher in severe DILI group than that of mild DILI group. AUCs for TG/HDL-C ratio to indicate the severity of DILI was 0.89 (P < 0.05), the cut-off point was 2.35. Dyslipidemia and TG/HDL-C ratio were related to DILI occurrence. Severe liver injury in DILI was associated with dyslipidemia and elevated TG/HDL-C ratio.

Deficiency of angiopoietin-like 4 enhances CD8+ T cell bioactivity via metabolic reprogramming for impairing tumour progression.

Angiopoietin-like 4 (ANGPTL4) is a secreted metabolism-modulating glycoprotein involved in the progression of tumours, cardiovascular diseases, metabolic syndrome and infectious diseases. In this study, more CD8+ T cells were activated to be effector T cells in ANGPTL4-/- mice. Impaired growth of tumours implanted in 3LL, B16BL6 or MC38 cells and reduced metastasis by B16F10 cells were observed in ANGPTL4-/- mice. Bone marrow (BM) transplantation experiments displayed that deficiency of ANGPTL4 in either host or BM cells promoted CD8+ T cell activation. However, ANGPTL4 deficiency in CD8+ T cells themselves showed more efficient anti-tumour activities. Recombinant ANGPTL4 protein promoted tumour growth in vivo with the less CD8+ T cell infiltration and it directly downregulated CD8+ T cell activation ex vivo. Transcriptome sequencing and metabolism analysis identified that ANGPTL4-/- CD8+ T cells increased glycolysis and decreased oxidative phosphorylation, which was dependent on the PKCζ-LKB1-AMPK-mTOR signalling axis. Reverse correlation of elevated ANGPTL4 levels in sera and tumour tissues with activated CD8+ T cells in the peripheral blood was displayed in patients with colorectal cancer. These results demonstrated that ANGPTL4 decreased immune surveillance in tumour progression by playing an immune-modulatory role on CD8+ T cells via metabolic reprogramming. Efficient blockade of ANGPTL4 expression in tumour patients would generate an effective anti-tumour effect mediated by CD8+ T cells.

Polarizer-free measurement of the full Stokes vector using a fiber-coupled superconducting nanowire single photon detector with a polarization extinction ratio of ∼2.

The characterization and manipulation of polarization state at single photon level are of great importance in research fields such as quantum information processing and quantum key distribution, where photons are normally delivered using single mode optical fibers. To date, the demonstrated polarimetry measurement techniques based on a superconducting nanowire single photon detector (SNSPD) require the SNSPD to be either highly sensitive or highly insensitive to the photon's polarization state, therefore placing an unavoidable challenge on the SNSPD's design and fabrication processes. In this article, we present the development of an alternative polarimetry measurement technique, of which the stringent requirement on the SNSPD's polarization sensitivity is removed. We validate the proposed technique by a rigorous theoretical analysis and comparisons of the experimental results obtained using a fiber-coupled SNSPD with a polarization extinction ratio of ∼2 to that obtained using other well-established known methods. Based on the full Stokes data measured by the proposed technique, we also demonstrate that at the single photon level (∼ -100 dBm), the polarization state of the photon delivered to the superconducting nanowire facet plane can be controlled at will using a further developed algorithm. Note that other than the fiber-coupled SNSPD, the only component involved is a quarter-wave plate (no external polarizer is necessary), which when aligned well has a paid insertion loss less than 0.5 dB.

Inducement of ER Stress by PAD Inhibitor BB-Cl-Amidine to Effectively Kill AML Cells.

OBJECTIVE: Acute myeloid leukemia (AML) is a highly heterogeneous and recurrent hematological malignancy. Despite the emergence of novel chemotherapy drugs, AML patients' complete remission (CR) remains unsatisfactory. Consequently, it is imperative to discover new therapeutic targets or medications to treat AML. Such epigenetic changes like DNA methylation and histone modification play vital roles in AML. Peptidylarginine deminase (PAD) is a protein family of histone demethylases, among which the PAD2 and PAD4 expression have been demonstrated to be elevated in AML patients, thus suggesting a potential role of PADs in the development or maintenance of AML and the potential for the identification of novel therapeutic targets. METHODS: AML cells were treated in vitro with the pan-PAD inhibitor BB-Cl-Amidine (BB-Cl-A). The AML cell lines were effectively induced into apoptosis by BB-Cl-A. However, the PAD4-specific inhibitor GSK484 did not. RESULTS: PAD2 played a significant role in AML. Furthermore, we found that BB-Cl-A could activate the endoplasmic reticulum (ER) stress response, as evidenced by an increase in phosphorylated PERK (p-PERK) and eIF2α (p-eIF2α). As a result of the ER stress activation, the BB-Cl-A effectively induced apoptosis in the AML cells. CONCLUSION: Our findings indicated that PAD2 plays a role in ER homeostasis maintenance and apoptosis prevention. Therefore, targeting PAD2 with BB-Cl-A could represent a novel therapeutic strategy for treating AML.

Fast and accurate measurement of the polarization-dependent detection efficiency of superconducting nanowire single photon detectors.

Superconducting nanowire single photon detectors (SNSPDs) have been extensively investigated due to their superior characteristics, including high system detection efficiency, low dark count rate and short recovery time. The polarization sensitivity introduced by the meandering-type superconductor nanowires is an intrinsic property of SNSPD, which is normally measured by sweeping hundreds of points on the Poincaré sphere to overcome the unknown birefringent problem of the SNSPD's delivery fiber. In this paper, we propose an alternative method to characterize the optical absorptance of SNSPDs, without sweeping hundreds of points on the Poincaré sphere. It is shown theoretically that measurements on the system detection efficiencies (SDEs) subject to cases of four specific photon polarization states are sufficient to reveal the two eigen-absorptances of the SNSPD. We validate the proposed method by comparing the measured detection spectra with the spectra attained from sweeping points on the Poincaré sphere and the simulated absorption spectra.

Triglyceride to HDL-C ratio is associated with plasma D-dimer levels in different types of pancreatitis.

This study aims to evaluate levels of D-dimer and serum lipid in different types of pancreatitis, and the relationship between D-dimer and dyslipidemia, especially triglyceride to HDL-C ratio (TG/HDL-C) in different types of pancreatitis. We analyzed the D-dimer and dyslipidemia levels in acute pancreatitis (AP), recurrent acute pancreatitis (RAP) and chronic pancreatitis (CP). A single-centered retrospective study was conducted on 1013 patients diagnosed with AP, RAP or CP. Only patients hospitalized within 24 h of onset were included, and 204 patients were enrolled in pancreatitis groups. 68 normal persons without pancreatitis, malignant diseases, pregnancy, or organ failure, who had health check-ups, were enrolled in the control group. Blood samples were taken within 24 h of admission. The relevant information on epidemiology and etiology was collected. D-dimer and serum lipid levels in different types of pancreatitis were analyzed. Furthermore, the area under the receiver-operating characteristic curve (AUC) was used to estimate the validity of the predictor and to define optimal cut-off points for prediction. We found that D-dimer and TG/HDL-C ratio could distinguish mild AP (MAP) and non-MAP in AP and RAP patients. The D-dimer level was related to TG/HDL-C ratio and severity of pancreatitis, with the coefficient correlation of 0.379 and 0.427(p < 0.05), respectively. TG/HDL-C was related to D-dimer in different types of pancreatitis. Logistic regression analysis was conducted in the parameters at admission like alcohol abuse, dyslipidemia and coagulation disturbance in distinguishing AP and RAP groups from the control group, and the parameter like diabetes in RAP and CP groups significantly increased compared with that of the control group. The value of D-dimer level and TG/HDL-C ratio in predicting the severity of AP and RAP was confirmed but there was no significant difference between CP group and the control group. The D-dimer level was related to dyslipidemia and TG/HDL-C ratio.