Human mesenchymal stromal cells ameliorate cisplatin-induced acute and chronic kidney injury via TSG-6.

Cisplatin is widely used in tumor chemotherapy, but nephrotoxicity is an unavoidable side effect of cisplatin. Several studies have demonstrated that mesenchymal stromal cells (MSCs) ameliorate cisplatin-induced kidney injury, but the underlying mechanisms are unknown. In this study, the cisplatin-induced kidney injury mouse model was established by subjecting a single intraperitoneal injection with cisplatin. One hour before cisplatin injection, the mice received human bone marrow MSCs (hBM-MSCs) with or without siRNA-transfection, recombinant human tumor necrosis factor-α-stimulated gene/protein 6 (rhTSG-6), or PBS through the tail vein. In addition, cisplatin-stimulated HK-2 cells were treated with hBM-MSCs or rhTSG-6. Human BM-MSCs treatment remarkably ameliorated cisplatin-induced acute and chronic kidney injury, as evidenced by significant reductions in serum creatinine (Scr), blood urea nitrogen, tubular injury, collagen deposition, α-smooth muscle actin accumulation, as well as inflammatory responses, and by remarkable increased anti-inflammatory factor expression and Treg cells infiltration in renal tissues. Furthermore, we found that only a few hBM-MSCs engrafted into damaged kidney and that the level of human TSG-6 in the serum of mice increased significantly following hBM-MSCs administration. Moreover, hBM-MSCs significantly increased the viability of damaged HK-2 cells and decreased the levels of inflammatory cytokines in the culture supernatant. However, the knockdown of the TSG-6 gene in hBM-MSCs significantly attenuated their beneficial effects in vivo and in vitro. On the contrary, treated with rhTSG-6 achieved similar beneficial effects of hBM-MSCs. Our results indicate that systemic administration of hBM-MSCs alleviates cisplatin-induced acute and chronic kidney injury in part by paracrine TSG-6 secretion.

Annexin A11 mutations are associated with nuclear envelope dysfunction in vivo and in human tissue.

Annexin A11 mutations are a rare cause of amyotrophic lateral sclerosis (ALS), wherein replicated protein variants P36R, G38R, D40G and D40Y are located in a small-alpha helix within the long, disordered N-terminus. To elucidate disease mechanisms, we characterised the phenotypes induced by a genetic loss of function (LoF) and by misexpression of G38R and D40G in vivo. Loss of Annexin A11 results in a low-penetrant behavioural phenotype and aberrant axonal morphology in zebrafish homozygous knockout larvae, which is rescued by human WT Annexin A11. Both Annexin A11 knockout/down and ALS variants trigger nuclear dysfunction characterised by Lamin B2 mis-localisation. The Lamin B2 signature also presented in anterior horn, spinal cord neurons from post-mortem ALS+/-FTD patient tissue possessing G38R and D40G protein variants. These findings suggest mutant Annexin A11 acts as a dominant negative, revealing a potential early nucleopathy highlighting nuclear envelope abnormalities preceding behavioural abnormality in animal models.

Perceptual training improves audiovisual integration by enhancing alpha-band oscillations and functional connectivity in older adults.

Numerous studies on perceptual training exist, however, most have focused on the precision of temporal audiovisual perception, while fewer have concentrated on ability promotion for audiovisual integration (AVI). To investigate these issues, continuous 5-day audiovisual perceptual training was applied, during which electroencephalography was performed in response to auditory-only (A), visual-only (V) and audiovisual (AV) stimuli before and after training. The results showed that the perceptual sensitivity was greater for training group than for control group and was greater in the posttest than in the pretest. The response to the AV stimulus was significantly faster in the posttest than in the pretest for the older training group but was significantly greater for A and V stimuli for the younger training group. Electroencephalography analysis found higher P3 AVI amplitudes [AV-(A + V)] in the posttest than in the pretest for training group, which were subsequently reflected by an increased alpha (8-12 Hz) oscillatory response and strengthened global functional connectivity (weighted phase lag index). Furthermore, these facilitations were greater for older training groups than for younger training groups. These results confirm the age-related compensatory mechanism for AVI may be strengthened as audiovisual perceptual training progresses, providing an effective candidate for cognitive intervention in older adults.

A novel imprinted locus on bovine chromosome 18 homologous with human chromosome 16q24.1.

Genomic imprinting is an epigenetic regulation mechanism in mammals resulting in the parentally dependent monoallelic expression of genes. Imprinting disorders in humans are associated with several congenital syndromes and cancers and remain the focus of many medical studies. Cattle is a better model organism for investigating human embryo development than mice. Imprinted genes usually cluster on chromosomes and are regulated by different methylation regions (DMRs) located in imprinting control regions that control gene expression in cis. There is an imprinted locus on human chromosome 16q24.1 associated with congenital lethal developmental lung disease in newborns. However, genomic imprinting on bovine chromosome 18, which is homologous with human chromosome 16 has not been systematically studied. The aim of this study was to analyze the allelic expressions of eight genes (CDH13, ATP2C2, TLDC1, COTL1, CRISPLD2, ZDHHC7, KIAA0513, and GSE1) on bovine chromosome 18 and to search the DMRs associated gene allelic expression. Three transcript variants of the ZDHHC7 gene (X1, X2, and X5) showed maternal imprinting in bovine placentas. In addition, the monoallelic expression of X2 and X5 was tissue-specific. Five transcripts of the KIAA0513 gene showed tissue- and isoform-specific monoallelic expression. The CDH13, ATP2C2, and TLDC1 genes exhibited tissue-specific imprinting, however, COTL1, CRISLPLD2, and GSE1 escaped imprinting. Four DMRs, established after fertilization, were found in this region. Two DMRs were located between the ZDHHC7 and KIAA0513 genes, and two were in exon 1 of the CDH13 and ATP2C2 genes, respectively. The results from this study support future studies on the molecular mechanism to regulate the imprinting of candidate genes on bovine chromosome 18.

Four and a half LIM domains 2 (FHL2) attenuates tumorigenesis of gastrointestinal stromal tumors (GISTs) by negatively regulating KIT signaling.

Gastrointestinal stromal tumors (GISTs) are predominately induced by KIT mutants. In this study, we found that four and a half LIM domains 2 (FHL2) was highly expressed in GISTs and KIT signaling dramatically increased FHL2 transcription while FHL2 inhibited KIT transcription. In addition, our results showed that FHL2 associated with KIT and increased the ubiquitination of both wild-type KIT and primary KIT mutants in GISTs, leading to decreased expression and activation of KIT although primary KIT mutants were less inhibited by FHL2 than wild-type KIT. In the animal experiments, loss of FHL2 expression in mice carrying germline KIT/V558A mutation which can develop GISTs resulted in increased tumor growth, but increased sensitivity of GISTs to imatinib treatment which is used as the first-line targeted therapy of GISTs, suggesting that FHL2 plays a role in the response of GISTs to KIT inhibitor. Unlike wild-type KIT and primary KIT mutants, we further found that FHL2 didn't alter the expression and activation of drug-resistant secondary KIT mutants. Taken together, our results indicated that FHL2 acts as the negative feedback of KIT signaling in GISTs while primary KIT mutants are less sensitive and secondary KIT mutants are resistant to the inhibition of FHL2.

Inhibition of ABI2 ubiquitination-dependent degradation suppresses TNBC cell growth via down-regulating PI3K/Akt signaling pathway.

Triple negative breast cancer (TNBC) is a type of cancer that lacks receptor expression and has complex molecular mechanisms. Recent evidence shows that the ubiquitin-protease system is closely related to TNBC. In this study, we obtain a key ubiquitination regulatory substrate-ABI2 protein by bioinformatics methods, which is also closely related to the survival and prognosis of TNBC. Further, through a series of experiments, we demonstrated that ABI2 expressed at a low level in TNBC tumors, and it has the ability to control cell cycle and inhibit TNBC cell migration, invasion and proliferation. Molecular mechanism studies proved E3 ligase CBLC could increase the ubiquitination degradation of ABI2 protein. Meanwhile, RNA-seq and IP experiments indicated that ABI2, acting as a crucial factor of tumor suppression, can significantly inhibit PI3K/Akt signaling pathway via the interaction with Rho GTPase RAC1. Finally, based on TNBC drug target ABI2, we screened and found that FDA-approved drug Colistimethate sodium(CS) has significant potential in suppressing the proliferation of TNBC cells and inducing cell apoptosis, making it a promising candidate for impeding the progression of TNBC.

Urine albumin-to-creatinine ratio diurnal variation rate predicts outcomes in idiopathic membranous nephropathy.

BACKGROUND: Idiopathic membranous nephropathy (IMN) is a leading cause of end-stage renal disease (ESRD). The purpose of this study was to evaluate whether urinary albumin-to-creatinine ratio (UACR) diurnal variation rate calculated by spot urinary protein test predicts 1-year nephrotic outcomes as a biomarker of proteinuria severity in patients with IMN. METHODS: Patients' baseline demographics, blood and urinary biomarkers, and clinical and pathological characteristics were collected retrospectively. Urine samples were collected at 7:00 (before breakfast) and 19:00 (after dinner) to calculate the UACR diurnal variation rate. A prediction model for no remission (NR) was developed statistically based on differences between prognosis groups. Receiver operating characteristic curve (ROC) analysis was performed to evaluate prediction abilities and determine optimal cut-off points of the model and UACR diurnal variation rate alone. RESULTS: The formula for calculating the probability of NR was exp(L)/(1 + exp(L)), where the linear predictor L = - 22.038 + 0.134 × Age (years) + 0.457 × 24-h urinary protein + 0.511 × blood urea nitrogen (BUN) + 0.014 × serum uric acid (SUA) + 2.411 if glomerular sclerosis + 0.816 × fasting blood glucose (FBG)-0.039 × UACR diurnal variation rate (%). Optimal cut-off points for NR prediction by the final model and UACR diurnal variation rate alone were 0.331 and 58.5%, respectively. Sensitivity and specificity were 0.889 and 0.859 for the final model, and 0.926 and 0.676 for UACR diurnal variation rate alone. CONCLUSION: UACR diurnal variation using spot urinary protein is a simpler way to predict nephrotic outcomes and is a highly sensitive screening tool for identifying patients who should undergo further comprehensive risk assessment.

ZFAT (isoform-specific) and its antisense RNA 1 (ZFAT-AS1) are two allele-specific monoallelically expressed genes in cattle.

In mammals, imprinted genes are characterised by a monoallelic expression, which is based on parental origin and is essential for both foetal and placental development. The ZFAT gene encodes a transcriptional factor, and its non-coding antisense RNA, ZFAT-AS1, overlaps with the ZFAT locus. Both ZFAT and ZFAT-AS1 are maternally imprinted in human placentas. In bovines, the imprinting status of the ZFAT and ZFAT-AS1 genes has yet to be reported. In this study, we analysed the allelic expression of three transcript variants (X1-X3) of the bovine ZFAT and ZFAT-AS1 genes in somatic tissues and placentas using a single nucleotide polymorphism-based method. The results showed that bovine ZFAT exhibited isoform-specific paternal expression. The ZFAT X2 variant exhibited monoallelic expression in the bovine placentas and biallelic expression in the six bovine somatic tissues (heart, liver, spleen, lung, kidney and brain). However, the ZFAT X1 and X3 variants were biallelically expressed in both bovine tissues and placentas. A 311 bp bovine ZFAT-AS1 complementary DNA (cDNA) sequence was obtained by aligning the human ZFAT-AS1 cDNA sequence with the bovine genome and conducting reverse transcription polymerase chain reaction amplification. Bovine ZFAT-AS1 have monoallelic expression in bovine placentas and somatic tissues. In addition, the DNA methylation of two regions was characterised, including the partial promoter, and exon 1 and intron 1 regions of ZFAT, and there were no differentially methylated regions.

The landscape of allelic expression and DNA methylation at the bovine SGCE/PEG10 locus.

Genomic imprinting is an epigenetic regulation in mammals in which a small subset of genes is monoallelically expressed dependent on their parental origin. A large imprinted domain, SGCE/PEG10 locus, is located on human chromosome 7q21s and mouse proximal chromosome 6. However, genomic imprinting of bovine SGCE/PEG10 cluster has not been systematically studied. In this study, we investigated allele expression of 14 genes of the SGCE/PEG10 locus in bovine somatic tissues and term placenta using a single nucleotide polymorphism (SNP)-based sequencing method. In addition to SGCE and PEG10, two conserved paternally expressed genes in human and mice, five other genes (TFPI2, GNG11, ASB4, PON1, and PON3) were paternally expressed. Three genes, BET1, COL1A2, and CASD1, exhibited tissue-specific monoallelic expression. CALCR showed monoallelic expression in tissues but biallelic expression in the placenta. Three genes, GNGT1, PPP1R9A, and PON2, showed biallelic expression in cattle. Five differentially methylated regions (DMRs) were found to be associated with the allelic expression of TFPI2, COL1A2, SGCE/PEG10, PON3, and ASB4 genes, respectively. The SGCE/PEG10 DMR is a maternally hypermethylated germline DMR, but TFPI2, COL1A2, PON3, and ASB4 DMRs are secondary DMRs. In summary, we identified five novel bovine imprinted genes (GNG11, BET1, COL1A2, CASD1, and PON1) and four secondary DMRs at the SGCE/PEG10 locus.

A metabolomics study on the mechanisms of Gardeniae fructus against α-naphthylisothiocyanate-induced cholestatic liver injury.

Gardeniae fructus (GF) is known for its various beneficial effects on cholestatic liver injury (CLI). However, the biological mechanisms through which GF regulates CLI have not been fully elucidated. This study aimed to explore the potential mechanisms of GF against α-naphthylisothiocyanate (ANIT)-induced CLI. First, HPLC technology was used to analyze the chemical profile of the GF extract. Second, the effects of GF on serum biochemical indicators and liver histopathology were examined. Lastly, metabolomics was utilized to study the changes in liver metabolites and clarify the associated metabolic pathways. In chemical analysis, 10 components were identified in the GF extract. GF treatment regulated serum biochemical indicators in ANIT-induced CLI model rats and alleviated liver histological damage. Metabolomics identified 26 endogenous metabolites as biomarkers of ANIT-induced CLI, with 23 biomarkers returning to normal levels, particularly involving primary bile acid biosynthesis, glycerophospholipid metabolism, tryptophan metabolism, and arachidonic acid metabolism. GF shows promise in alleviating ANIT-induced CLI by modulating multiple pathways.

Liposomes in the cosmetics: present and outlook.

Liposomes are small spherical vesicles composed of phospholipid bilayers capable of encapsulating a variety of ingredients, including water- and oil-soluble compound, which are one of the most commonly used piggybacking and delivery techniques for many active ingredients and different compounds in biology, medicine and cosmetics. With the increasing number of active cosmetic ingredients, the concomitant challenge is to effectively protect, transport, and utilize these substances in a judicious manner. Many cosmetic ingredients are ineffective both topically and systemically when applied to the skin, thus changing the method of delivery and interaction with the skin of the active ingredients is a crucial step toward improving their effectiveness. Liposomes can improve the delivery of active ingredients to the skin, enhance their stability, and ultimately, improve the efficacy of cosmetics and and pharmaceuticals. In this review, we summarized the basic properties of liposomes and their recent advances of functionalities in cosmetics and and pharmaceuticals. Also, the current state of the art in the field is discussed and the prospects for future research areas are highlighted. We hope that this review will provide ideas and inspiration on the application and development of cosmetics and pharmaceuticals.

Transcriptome and Hormonal Analysis of Agaricus bisporus Basidiome Response to Hypomyces perniciosus Infection.

Agaricus bisporus (Lange) Imbach is the most widely cultivated mushroom in the world. A. bisporus wet bubble disease is one of the most severe diseases of white button mushrooms and is caused by the fungal pathogen Hypomyces perniciosus. The pathogen causes a drastic reduction in mushroom yield because of malformation and deterioration of the basidiomes. However, the mechanism of the button mushroom's malformation development after infection with H. perniciosus remains obscure. Therefore, to reveal the mechanism of A. bisporus malformation caused by H. perniciosus, the interaction between the pathogen and host was investigated in this study using histopathological, physiological, and transcriptomic analyses. Results showed that irrespective of the growth stages of A. bisporus basidiomes infected with H. perniciosus, the host's malformed basidiomes and enlarged mycelia and basidia indicated that the earlier the infection with H. perniciosus, the more the malformation of the basidiomes. Analyzing physiological and transcriptomic results in tandem, we concluded that H. perniciosus causes malformation development of A. bisporus mainly by affecting the metabolism level of phytohormones (N6-isopentenyladenosine, cis-zeatin, and N6-[delta 2-isopentenyl]-adenine) of the host's fruiting bodies rather than using toxins. Our findings revealed the mechanism of the button mushroom's malformation development after infection with H. perniciosus, providing a reference for developing realistic approaches to control mushroom diseases. Our results further clarified the interaction between A. bisporus and H. perniciosus and identified the candidate genes for A. bisporus wet bubble disease resistance breeding. Additionally, our work provides a valuable theoretical basis and technical support for studying the interaction between other pathogenic fungi and their fungal hosts.

Single-atom catalysts: promotors of highly sensitive and selective sensors.

Sensors, the underlying technology that supports the Internet of Things, are undergoing multi-disciplinary integration development to constantly improve the efficiency of human production and life. Simultaneously, the application scenarios in emerging fields such as medical diagnosis, environmental monitoring and industrial safety put forward higher requirements for sensing capabilities. Over the last decade, single-atom catalysts (SACs) have attracted tremendous attention in fields such as environment and energy due to their high atom utilization efficiencies, controllable active sites, tailorable coordination environments and structural/chemical stability. These extraordinary characteristics extend the sensitivity and selectivity of sensors beyond their current limitations. Here, we start with the working principles of SAC-based sensors, and summarize the relationship between sensor performance and intrinsic properties of SACs, followed by an overview of the design strategy development. We then review the recent advances in SAC-based sensors in different fields and highlight the future opportunities and challenges in their exciting applications.

Predictive model for epileptogenic tubers from all tubers in patients with tuberous sclerosis complex based on 18F-FDG PET: an 8-year single-centre study.

BACKGROUND: More than half of patients with tuberous sclerosis complex (TSC) suffer from drug-resistant epilepsy (DRE), and resection surgery is the most effective way to control intractable epilepsy. Precise preoperative localization of epileptogenic tubers among all cortical tubers determines the surgical outcomes and patient prognosis. Models for preoperatively predicting epileptogenic tubers using 18F-FDG PET images are still lacking, however. We developed noninvasive predictive models for clinicians to predict the epileptogenic tubers and the outcome (seizure freedom or no seizure freedom) of cortical tubers based on 18F-FDG PET images. METHODS: Forty-three consecutive TSC patients with DRE were enrolled, and 235 cortical tubers were selected as the training set. Quantitative indices of cortical tubers on 18F-FDG PET were extracted, and logistic regression analysis was performed to select those with the most important predictive capacity. Machine learning models, including logistic regression (LR), linear discriminant analysis (LDA), and artificial neural network (ANN) models, were established based on the selected predictive indices to identify epileptogenic tubers from multiple cortical tubers. A discriminating nomogram was constructed and found to be clinically practical according to decision curve analysis (DCA) and clinical impact curve (CIC). Furthermore, testing sets were created based on new PET images of 32 tubers from 7 patients, and follow-up outcome data from the cortical tubers were collected 1, 3, and 5 years after the operation to verify the reliability of the predictive model. The predictive performance was determined by using receiver operating characteristic (ROC) analysis. RESULTS: PET quantitative indices including SUVmean, SUVmax, volume, total lesion glycolysis (TLG), third quartile, upper adjacent and standard added metabolism activity (SAM) were associated with the epileptogenic tubers. The SUVmean, SUVmax, volume and TLG values were different between epileptogenic and non-epileptogenic tubers and were associated with the clinical characteristics of epileptogenic tubers. The LR model achieved the better performance in predicting epileptogenic tubers (AUC = 0.7706; 95% CI 0.70-0.83) than the LDA (AUC = 0.7506; 95% CI 0.68-0.82) and ANN models (AUC = 0.7425; 95% CI 0.67-0.82) and also demonstrated good calibration (Hosmer‒Lemeshow goodness-of-fit p value = 0.7). In addition, DCA and CIC confirmed the clinical utility of the nomogram constructed to predict epileptogenic tubers based on quantitative indices. Intriguingly, the LR model exhibited good performance in predicting epileptogenic tubers in the testing set (AUC = 0.8502; 95% CI 0.71-0.99) and the long-term outcomes of cortical tubers (1-year outcomes: AUC = 0.7805, 95% CI 0.71-0.85; 3-year outcomes: AUC = 0.8066, 95% CI 0.74-0.87; 5-year outcomes: AUC = 0.8172, 95% CI 0.75-0.87). CONCLUSIONS: The 18F-FDG PET image-based LR model can be used to noninvasively identify epileptogenic tubers and predict the long-term outcomes of cortical tubers in TSC patients.

Cavity-enhanced and temporally multiplexed atom-photon entanglement interface.

Practical realization of quantum repeaters requires quantum memories with high retrieval efficiency, multi-mode storage capacities, and long lifetimes. Here, we report a high-retrieval-efficiency and temporally multiplexed atom-photon entanglement source. A train of 12 write pulses in time is applied to a cold atomic ensemble along different directions, which generates temporally multiplexed pairs of Stokes photons and spin waves via Duan-Lukin-Cirac-Zoller processes. The two arms of a polarization interferometer are used to encode photonic qubits of 12 Stokes temporal modes. The multiplexed spin-wave qubits, each of which is entangled with one Stokes qubit, are stored in a "clock" coherence. A ring cavity that resonates simultaneously with the two arms of the interferometer is used to enhance retrieval from the spin-wave qubits, with the intrinsic retrieval efficiency reaching 70.4%. The multiplexed source gives rise to a ∼12.1-fold increase in atom-photon entanglement-generation probability compared to the single-mode source. The measured Bell parameter for the multiplexed atom-photon entanglement is 2.21(2), along with a memory lifetime of up to ∼125 µs.

SPRY4 inhibits and sensitizes the primary KIT mutants in gastrointestinal stromal tumors (GISTs) to imatinib.

BACKGROUND: KIT is frequently mutated in gastrointestinal stromal tumors (GISTs), and the treatment of GISTs largely relies on targeting KIT currently. In this study, we aimed to investigate the role of sprouty RTK signaling antagonist 4 (SPRY4) in GISTs and related mechanisms. METHODS: Ba/F3 cells and GIST-T1 cell were used as cell models, and mice carrying germline KIT/V558A mutation were used as animal model. Gene expression was examined by qRT-PCR and western blot. Protein association was examined by immunoprecipitation. RESULTS: Our study revealed that KIT increased the expression of SPRY4 in GISTs. SPRY4 was found to bind to both wild-type KIT and primary KIT mutants in GISTs, and inhibited KIT expression and activation, leading to decreased cell survival and proliferation mediated by KIT. We also observed that inhibition of SPRY4 expression in KITV558A/WT mice led to increased tumorigenesis of GISTs in vivo. Moreover, our results demonstrated that SPRY4 enhanced the inhibitory effect of imatinib on the activation of primary KIT mutants, as well as on cell proliferation and survival mediated by the primary KIT mutants. However, in contrast to this, SPRY4 did not affect the expression and activation of drug-resistant secondary KIT mutants, nor did it affect the sensitivity of secondary KIT mutants to imatinib. These findings suggested that secondary KIT mutants regulate a different downstream signaling cascade than primary KIT mutants. CONCLUSIONS: Our results suggested that SPRY4 acts as negative feedback of primary KIT mutants in GISTs by inhibiting KIT expression and activation. It can increase the sensitivity of primary KIT mutants to imatinib. In contrast, secondary KIT mutants are resistant to the inhibition of SPRY4.

CRISPR-Cas12a coupled with universal gold nanoparticle strand-displacement probe for rapid and sensitive visual SARS-CoV-2 detection.

Point of care (POC) diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are particularly significant for preventing transmission of coronavirus disease 2019 (COVID-19) by any user at any given time and place. CRISPR/Cas-assisted SARS-CoV-2 assays are viewed as supplemental to RT-PCR due to simple operation, convenient use and low cost. However, most current CRISPR molecular diagnostics based on fluorescence measurement increased the difficulty of POC test with need of the additional light sources. Some instrument-free visual detection with the naked eye has limitations in probe universality. Herein, we developed a universal, rapid, sensitive and specific SARS-CoV-2 POC test that combines the outstanding DNase activity of Cas12a with universal AuNPs strand-displacement probe. The oligo trigger, which is the switch the AuNPs of the strand-displacement probe, is declined as a result of Cas12a recognition and digestion. The amount of released AuNPs produced color change which can be visual with the naked eye and assessed by UV-Vis spectrometer for quantitative detection. Furthermore, a low-cost hand warmer is used as an incubator for the visual assay, enabling an instrument-free, visual SARS-CoV-2 detection within 20 min. A real coronavirus GX/P2V instead of SARS-CoV-2 were chosen for practical application validation. After rapid virus RNA extraction and RT-PCR amplification, a minimum of 2.7 × 102 copies/mL was obtained successfully. The modular design can be applied to many nucleic acid detection applications, such as viruses, bacteria, species, etc., by simply modifying the crRNA, showing great potential in POC diagnosis.

Semiconductor-Metal Phase Transition and Emergent Charge Density Waves in 1T-ZrX2 (X = Se, Te) at the Two-Dimensional Limit.

A charge density wave (CDW) is a collective quantum phenomenon in metals and features a wavelike modulation of the conduction electron density. A microscopic understanding and experimental control of this many-body electronic state in atomically thin materials remain hot topics in materials physics. By means of material engineering, we realized a dimensionality and Zr intercalation induced semiconductor-metal phase transition in 1T-ZrX2 (X = Se, Te) ultrathin films, accompanied by a commensurate 2 × 2 CDW order. Furthermore, we observed a CDW energy gap of up to 22 meV around the Fermi level. Fourier-transformed scanning tunneling microscopy and angle-resolved photoemission spectroscopy reveal that 1T-ZrX2 films exhibit the simplest Fermi surface among the known CDW materials in TMDCs, consisting only of a Zr 4d derived elliptical electron conduction band at the corners of the Brillouin zone.

Retrieval of sound-velocity profile in ocean by employing Brillouin scattering LiDAR.

Accurate remote sensing of the sound velocity profile of the upper-ocean mixed layers is of major important in oceanography, especially in underwater acoustic communication. However, the existing technologies cannot realize fast and real-time detection on sound velocity profile, a cost efficiency, flexibility, and real-time remote sensing technique is still highly urgent. In this paper, we propose a novel approach based on stimulated Brillouin scattering (SBS) LiDAR for retrieving the sound velocity profile. The sound velocity profiles in the upper-ocean mixed layer of South China Sea were retrieved theoretically and experimentally. We simulated the sound velocity profile of the upper-ocean mixed layer in South China Sea by using the Del Grosso algorithm and the data of temperature, salinity, depth selected from the World Ocean Atlas 2018 (WOA18). We designed a special ocean simulation system to measure the sound velocity in seawater with different temperatures, salinities, and pressures through measuring the frequency shift of SBS. Based on the measured sound velocities, we built a retrieval equation to express the sound velocity as a function of temperature, salinity, and pressure. Then, we retrieved the sound velocity profile of the upper-ocean mixed layer of South China Sea by using the retrieval equation. The results show that the retrieved sound velocity profile is good agreement with the theoretical simulation, and the difference between them is approximately 1∼2 m/s. Also, we have analyzed the differences between the theoretical simulation and experimental measurement. This work is essential to future application for remote sensing the sound velocity distribution profiles of the upper-ocean mixed layers by using the Brillouin LiDAR technique.

Generation of entanglement between a highly wave-packet-tunable photon and a spin-wave memory in cold atoms.

Controls of waveforms (pulse durations) of single photons are important tasks for effectively interconnecting disparate atomic memories in hybrid quantum networks. So far, the waveform control of a single photon that is entangled with an atomic memory remains unexplored. Here, we demonstrated control of waveform length of the photon that is entangled with an atomic spin-wave memory by varying light-atom interaction time in cold atoms. The Bell parameter S as a function of the duration of photon pulse is measured, which shows that violations of Bell inequality can be achieved for the photon pulse in the duration range from 40 ns to 50 µs, where, S = 2.64 ± 0.02 and S = 2.26 ± 0.05 for the 40-ns and 50-µs durations, respectively. The measured results show that S parameter decreases with the increase in the pulse duration. We confirm that the increase in photon noise probability per pulse with the pulse-duration is responsible for the S decrease.