Dual ablation of the RyR2-Ser2808 and RyR2-Ser2814 sites increases propensity for pro-arrhythmic spontaneous Ca2+ releases.

During exercise or stress, the sympathetic system stimulates cardiac contractility via ß-adrenergic receptor (ß-AR) activation, resulting in phosphorylation of the cardiac ryanodine receptor (RyR2). Three RyR2 phosphorylation sites have taken prominence in excitation-contraction coupling: S2808 and S2030 are described as protein kinase A specific and S2814 as a Ca2+/calmodulin kinase type-2-specific site. To examine the contribution of these phosphosites to Ca2+ signalling, we generated double knock-in (DKI) mice in which Ser2808 and Ser2814 phosphorylation sites have both been replaced by alanine (RyR2-S2808A/S2814A). These mice did not exhibit an overt phenotype. Heart morphology and haemodynamic parameters were not altered. However, they had a higher susceptibility to arrhythmias. We performed confocal Ca2+ imaging and electrophysiology experiments. Isoprenaline was used to stimulate ß-ARs. Measurements of Ca2+ waves and latencies in myocytes revealed an increased propensity for spontaneous Ca2+ releases in DKI myocytes, both in control conditions and during ß-AR stimulation. In DKI cells, waves were initiated from a lower threshold concentration of Ca2+ inside the sarcoplasmic reticulum, suggesting higher Ca2+ sensitivity of the RyRs. The refractoriness of Ca2+ spark triggering depends on the Ca2+ sensitivity of the RyR2. We found that RyR2-S2808A/S2814A channels were more Ca2+ sensitive in control conditions. Isoprenaline further shortened RyR refractoriness in DKI cardiomyocytes. Together, our results suggest that ablation of both the RyR2-Ser2808 and RyR2-S2814 sites increases the propensity for pro-arrhythmic spontaneous Ca2+ releases, as previously suggested for hyperphosphorylated RyRs. Given that the DKI cells present a full response to isoprenaline, the data suggest that phosphorylation of Ser2030 might be sufficient for ß-AR-mediated sensitization of RyRs. KEY POINTS: Phosphorylation of cardiac sarcoplasmic reticulum Ca2+-release channels (ryanodine receptors, RyRs) is involved in the regulation of cardiac function. Ablation of both the RyR2-Ser2808 and RyR2-Ser2814 sites increases the propensity for pro-arrhythmic spontaneous Ca2+ releases, as previously suggested for hyperphosphorylated RyRs. The intra-sarcoplasmic reticulum Ca2+ threshold for spontaneous Ca2+ wave generation is lower in RyR2-double-knock-in cells. The RyR2 from double-knock-in cells exhibits increased Ca2+ sensitivity. Phosphorylation of Ser2808 and Ser2814 might be important for basal activity of the channel. Phosphorylation of Ser2030 might be sufficient for a ß-adrenergic response.

Exceptional Nexus in Bose-Einstein Condensates with Collective Dissipation.

In multistate non-Hermitian systems, higher-order exceptional points and exotic phenomena with no analogues in two-level systems arise. A paradigm is the exceptional nexus (EX), a third-order EP as the cusp singularity of exceptional arcs (EAs), that has a hybrid topological nature. Using atomic Bose-Einstein condensates to implement a dissipative three-state system, we experimentally realize an EX within a two-parameter space, despite the absence of symmetry. The engineered dissipation exhibits density dependence due to the collective atomic response to resonant light. Based on extensive analysis of the system's decay dynamics, we demonstrate the formation of an EX from the coalescence of two EAs with distinct geometries. These structures arise from the different roles played by dissipation in the strong coupling limit and quantum Zeno regime. Our Letter paves the way for exploring higher-order exceptional physics in the many-body setting of ultracold atoms.

Trivalent Organostibines: Sb,N Ligands in Double N-Arylation of Primary Amines toward Functionalized Carbazoles.

A Sb,N ligand (L-Sb) for Pd-catalyzed double N-arylation of primary amines was developed. This trivalent ligand L-Sb, containing a 5,6,7,12-tetrahydrodibenzo[c,f][1,5]azastibocine skeleton and stable under air and moisture, could be synthesized facilely on a gram scale from chlorostibine (1) and cyclopentylmagnesium bromide. L-Sb showed excellent catalytic performance in Pd2(dba)3-catalyzed double N-arylation of 2,2'-dibromo-1,1'-biphenyl (2) with primary amines (3), affording functionalized carbazoles in good yields. This Pd2(dba)3/L-Sb-catalyzed double N-arylation, the first example of the application of trivalent organostibines as a ligand in N-arylation, featured the following advantages: small catalyst loading, wide functional group tolerance, good yields, and ease of gram-scale synthesis.

Quantitative and dynamic profiling of human gut core microbiota by real-time PCR.

The human gut microbiota refers to a diverse community of microorganisms that symbiotically exist in the human intestinal system. Altered microbial communities have been linked to many human pathologies. However, there is a lack of rapid and efficient methods to assess gut microbiota signatures in practice. To address this, we established an appraisal system containing 45 quantitative real-time polymerase chain reaction (qPCR) assays targeting gut core microbes with high prevalence and/or abundance in the population. Through comparative genomic analysis, we selected novel species-specific genetic markers and primers for 31 of the 45 core microbes with no previously reported specific primers or whose primers needed improvement in specificity. We comprehensively evaluated the performance of the qPCR assays and demonstrated that they showed good sensitivity, selectivity, and quantitative linearity for each target. The limit of detection ranged from 0.1 to 1.0 pg/µL for the genomic DNA of these targets. We also demonstrated the high consistency (Pearson's r = 0.8688, P < 0.0001) between the qPCR method and metagenomics next-generation sequencing (mNGS) method in analyzing the abundance of selected bacteria in 22 human fecal samples. Moreover, we quantified the dynamic changes (over 8 weeks) of these core microbes in 14 individuals using qPCR, and considerable stability was demonstrated in most participants, albeit with significant individual differences. Overall, this study enables the simple and rapid quantification of 45 core microbes in the human gut, providing a promising tool to understand the role of gut core microbiota in human health and disease. KEY POINTS: • A panel of original qPCR assays was developed to quantify human gut core microbes. • The qPCR assays were evaluated and compared with mNGS using real fecal samples. • This method was used to dynamically profile the gut core microbiota in individuals.

Analyzing the photoassociation spectrum of ultracold 85Rb 133Cs molecule in (3)3Σ+ state.

We establish a theoretical model to analyze the photoassociative spectroscopy of 85Rb 133Cs molecules in the (3)3Σ+ state. The vibrational energy, spin-spin coupling constant, and hyperfine interaction constant of the (3)3Σ+ state are determined based on nine observed vibrational levels. Consequently, the Rydberg-Klein-Rees potential energy curve of the (3)3Σ+ state is obtained and compared with the ab initial potential energy curve. Our model can be adopted to analyze the photoassociative spectroscopy of other heteronuclear alkali-metal diatomic molecules in the (3)3Σ+ state.

Narrow laser linewidth measurement with the optimal demodulated Lorentzian spectrum: erratum.

This erratum corrects errors in Fig. 4(b) of the original paper, Appl. Opt.63, 1847 (2023)APOPAI0003-693510.1364/AO.510265. This correction does not affect any of the results or conclusions of the aforementioned paper.

Narrow laser linewidth measurement with the optimal demodulated Lorentzian spectrum.

A method called the optimal demodulated Lorentzian spectrum is employed to precisely quantify the narrowness of a laser's linewidth. This technique relies on the coherent envelope demodulation of a spectrum obtained through short delayed self-heterodyne interferometry. Specifically, we exploit the periodic features within the coherence envelope spectrum to ascertain the delay time of the optical fiber. Furthermore, the disparity in contrast within the coherence envelope spectrum serves as a basis for estimating the laser's linewidth. By creating a plot of the coefficient of determination for the demodulated Lorentzian spectrum fitting in relation to the estimated linewidth values, we identify the existence of an optimal Lorentzian spectrum. The corresponding laser linewidth found closest to the true value is deemed optimal. This method holds particular significance for accurately measuring the linewidth of lasers characterized as narrow or ultranarrow.

Identification and Functional Exploration of BraGASA Genes Reveal Their Potential Roles in Drought Stress Tolerance and Sexual Reproduction in Brassica rapa L. ssp. pekinensis.

Gibberellic acid-stimulated Arabidopsis sequences (GASAs) are a subset of the gibberellin (GA)-regulated gene family and play crucial roles in various physiological processes. However, the GASA genes in Brassica rapa have not yet been documented. In this study, we identified and characterized 16 GASA genes in Chinese cabbage (Brassica rapa L. ssp. pekinensis). Analysis of the conserved motifs revealed significant conservation within the activation segment of BraGASA genes. This gene family contains numerous promoter elements associated with abiotic stress tolerance, including those for abscisic acid (ABA) and methyl jasmonate (MeJA). Expression profiling revealed the presence of these genes in various tissues, including roots, stems, leaves, flowers, siliques, and callus tissues. When plants were exposed to drought stress, the expression of BraGASA3 decreased notably in drought-sensitive genotypes compared to their wild-type counterparts, highlighting the potentially crucial role of BraGASA3 in drought stress. Additionally, BraGASAs exhibited various functions in sexual reproduction dynamics. The findings contribute to the understanding of the function of BraGASAs and provide valuable insights for further exploration of the GASA gene function of the BraGASA gene in Chinese cabbage.

Transcriptomic and Proteomic Analyses Unveil the Role of Nitrogen Metabolism in the Formation of Chinese Cabbage Petiole Spot.

Chinese cabbage is the most widely consumed vegetable crop due to its high nutritional value and rock-bottom price. Notably, the presence of the physiological disease petiole spot significantly impacts the appearance quality and marketability of Chinese cabbage. It is well known that excessive nitrogen fertilizer is a crucial factor in the occurrence of petiole spots; however, the mechanism by which excessive nitrogen triggers the formation of petiole spots is not yet clear. In this study, we found that petiole spots initially gather in the intercellular or extracellular regions, then gradually extend into intracellular regions, and finally affect adjacent cells, accompanied by cell death. Transcriptomic and proteomic as well as physiology analyses revealed that the genes/proteins involved in nitrogen metabolism exhibited different expression patterns in resistant and susceptible Chinese cabbage lines. The resistant Chinese cabbage line has high assimilation ability of NH4+, whereas the susceptible one accumulates excessive NH4+, thus inducing a burst of reactive oxygen species (ROS). These results introduce a novel perspective to the investigation of petiole spot induced by the nitrogen metabolism pathway, offering a theoretical foundation for the development of resistant strains in the control of petiole spot.

Research on the improvement effect of Saposhnikovia divaricata (Trucz.) Schischk on rheumatoid arthritis based on the "component-target-pathway" association.

OBJECTIVE: To investigate the therapeutic effect and mechanism of the traditional Chinese medicine Saposhnikovia divaricata (Trucz.) Schischk in rats with complete Freund's adjuvant-induced rheumatoid arthritis (RA). METHODS: The chemical targets and RA targets of Saposhnikovia divaricata (Trucz.) Schischk were acquired by the network pharmacological method. The complete Freund's adjuvant-induced rat RA model was used to further explore the mechanism of Saposhnikovia divaricata (Trucz.) Schischk in improving RA. Pathological changes in the volume of toes, body weight and synovial tissues of joints as well as serum inflammatory factor levels before and after the intervention of Saposhnikovia divaricata (Trucz.) Schischk were investigated. The key metabolic pathways were screened by correlations between metabolites and key targets. Finally, a quantitative analysis of key targets and metabolites was experimentally validated. RESULTS: Saposhnikovia divaricata (Trucz.) Schischk administration increased body weight, mitigated foot swelling and downregulated inflammatory cytokine levels in model rats. The histopathology showed that treatment with Saposhnikovia divaricata (Trucz.) Schischk can induce inflammatory cell infiltration and synovial hyperplasia and obviously reduce cartilage injuries, thus improving arthritis symptoms in rats. According to the network pharmacology-metabonomics association analysis results, the purine metabolic signaling pathway might be the key pathway for RA intervention with Saposhnikovia divaricata (Trucz.) Schischk. Targeted metabonomics, Western blotting (WB) and reverse transcription-polymerase chain reaction (RT‒PCR) assays showed that the recombinant adenosine deaminase (ADA) mRNA expression level and metabolic level of inosine in Saposhnikovia divaricata (Trucz.) Schischk administration group were lower than those of the model group. This reflected that Saposhnikovia divaricata (Trucz.) Schischk could improve RA by downregulating ADA mRNA expression levels and the metabolic level of inosine in the purine signaling pathway. CONCLUSION: Based on the "component-disease-target" association analysis, this study concludes that Saposhnikovia divaricata (Trucz.) Schischk improves complete Freund's adjuvant-induced RA symptoms in rats mainly by downregulating ADA mRNA expression levels in the purine metabolic signaling pathway, mitigating foot swelling, improving the levels of serum inflammatory factors (IL-1ß, IL-6 and TNF-α), and decreasing the ADA protein expression level to intervene in purine metabolism.

Process-Divergent Syntheses of 4- and 5-Sulfur-Functionalized 1,2,3-Triazoles via Copper-Catalyzed Azide-Alkyne Cycloadditions of 1-Phosphinyl-2-sulfanylethynes.

4-Sulfanyl-substituted 1,2,3-triazoles were provided regioselectively with good yields and broad scope via consecutive t-BuOK-promoted dephosphinylation of 1-phosphinyl-2-sulfanylethynes and copper-catalyzed azide-alkyne cycloadditions (CuAAC) with alkyl azides. Unsymmetrically substituted ditriazoles were successfully obtained using a tandem dephosphinylative CuAAC protocol with diazides. Direct CuAAC of the 1-phosphinyl-2-sulfanylethynes with azides afforded regioisomeric mixtures of 4-phosphinyl-5-sulfanyl- and 5-phosphinyl-4-sulfanyl-1,2,3-triazoles that were easily separable from one another. When the phosphinyl- and sulfanyl-substituted triazoles were treated with t-BuOK, the dephosphination proceeded smoothly, yielding the corresponding 5- and 4-sulfanyltriazoles, respectively. 5-(1-Aryl-1-hydroxymethyl)-4-sulfanyltriazoles were synthesized by stepwise treatment of 5-phosphinyl-4-sulfanyltriazole with MeMgBr and arylaldehydes. Additionally, Ph2P(O) and RS groups in the triazoles were easily converted to Ph2P and RSO2 by PhSiH3-reduction and m-CPBA-oxidation, respectively. Following the dephosphinylative CuAAC of 1-phosphinyl-2-(4-t-butylphenylsulfanyl)ethyne with aryl azides and m-CPBA-oxidation, potent antagonists of pregnane X receptor LC-58 and LC-59 were successfully produced.

Simple, low-cost, and well-performing optical phase-locked loop for frequency and phase locking of semiconductor lasers.

We demonstrate a simple, low-cost, and well-performing optical phase-locked loop (OPLL) circuit with ADF4007 as the phase frequency detector chip to achieve frequency and phase locking of two semiconductor lasers in both short and long terms. The measured short term performances, determined by fast feedback, show that the spectral width of the beat signal is low, around 1 Hz, and the residual phasing error is 0.04r a d 2. The measured long term performances, determined by slow feedback, show that the drift of the central frequency of the beat signal is within 1.1(1) Hz in 2 h, and the derived Allan deviation is less than 0.4 Hz within all integration times of up to 1000 s. The phase noise measurement shows a suppression of phase noise of the beat signal from free running to closed-loop OPLLs in a Fourier frequency of 10 Hz-20 kHz. These measurements show that the OPLL circuit we modified can fit most scientific experiments requiring a fixed frequency difference and phase coherence.

Identification of DELLA gene family in head cabbage and analysis of mRNA transport in the heterograft.

DELLA gene family is involved in the regulation of signal transduction of plant hormones. mRNAs of GA insensitive (GAI), the member of DELLA gene family, are also signaling molecules of long-distance transport in plants. Genome-wide identification and mRNA transport analysis of the members of DELLA gene family in head cabbage (Brassica oleracea var. capitata) can provide basic data for their application in head cabbage. In this study, five members of DELLA gene family (BoRGA1, BoRGA2, BoRGL1, BoRGL2, and BoRGL3) were identified in head cabbage using genome and transcriptome data. However, head cabbage lacked a GAI gene in its genome. The scion (head cabbage, inbred line G27) and the rootstock Chinese flowering cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) (sijiucaixin) were cleft-grafted together to produce the heterograft. Inflorescence stem of the rootstock and the corresponding inflorescence stem in Chinese flowering cabbage seedlings (as controls) were purified and analyzed with transcriptome sequencing. The total of 8, 9, 3, 5, and 1 exogenous read(s), derived respectively from BoRGA1, BoRGA2, BoRGL1, BoRGL2, and BoRGL3, were identified in the transcriptomes of the rootstocks. Nevertheless, mRNA transport of DELLA family genes from scion to rootstock did not increase the transcriptional level of the members of DELLA gene family in the rootstocks. Correlation analysis suggested that mRNA transport efficiency of the DELLA family genes was correlated with the sequence and the transcriptional level of the respective DELLA gene in the scion (head cabbage). This study lays the foundation for further investigation on the molecular mechanism of mRNA transport of the members of DELLA gene family in head cabbage.

[Determination of 10 mycotoxins in Hippophae Fructus medicinal and edible products by ultra-performance liquid chromatography- tandem mass spectrometry].

An analytical method for 10 mycotoxins in Hippophae Fructus medicinal and edible products was established in this study, and the contamination of their mycotoxins was analyzed. First of all, the mixed reference solution of ten mycotoxins such as aflatoxin, ochratoxin, zearalenone, and dexoynivalenol was selected as the control, and the Hippophae Fructus medicinal and edible products were prepared. Secondly, based on the ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) technology, 10 mycotoxins in Hippophae Fructus medicinal and edible products were quantitatively investigated and their content was determined. Finally, the contamination of mycotoxins was analyzed and evaluated. The optimal analysis conditions were determined, and the methodological inspection results showed that the 10 mycotoxins established a good linear relationship(r>0.99). The method had good repeatability, test sample specificity, stability, and instrument precision. The average recovery rates of 10 mycotoxins in Hippophae Fructus medicinal products, edible solids, and edible liquids were 90.31%-109.4%, 87.86%-107.8%, and 85.61%-109.1%, respectively. Relative standard deviation(RSD) values were 0.22%-10%, 0.75%-13%, and 0.84%-8.5%, repsectively. Based on UPLC-MS/MS technology, the simultaneous determination method for the limits of 10 mycotoxins established in this study has fast detection speed, less matrix interference, high sensitivity, and accurate results, which is suitable for the limit examination of 10 mycoto-xins in Hippophae Fructus medicinal and edible products.

Preserved cardiac performance and adrenergic response in a rabbit model with decreased ryanodine receptor 2 expression.

Ryanodine receptor 2 (RyR2) is an ion channel in the heart responsible for releasing into the cytosol most of the Ca2+ required for contraction. Proper regulation of RyR2 is critical, as highlighted by the association between channel dysfunction and cardiac arrhythmia. Lower RyR2 expression is also observed in some forms of heart disease; however, there is limited information on the impact of this change on excitation-contraction (e-c) coupling, Ca2+-dependent arrhythmias, and cardiac performance. We used a constitutive knock-out of RyR2 in rabbits (RyR2-KO) to assess the extent to which a stable decrease in RyR2 expression modulates Ca2+ handling in the heart. We found that homozygous knock-out of RyR2 in rabbits is embryonic lethal. Remarkably, heterozygotes (KO+/-) show ~50% loss of RyR2 protein without developing an overt phenotype at the intact animal and whole heart levels. Instead, we found that KO+/- myocytes show (1) remodeling of RyR2 clusters, favoring smaller groups in which channels are more densely arranged; (2) lower Ca2+ spark frequency and amplitude; (3) slower rate of Ca2+ release and mild but significant desynchronization of the Ca2+ transient; and (4) a significant decrease in the basal phosphorylation of S2031, likely due to increased association between RyR2 and PP2A. Our data show that RyR2 deficiency, although remarkable at the molecular and subcellular level, has only a modest impact on global Ca2+ release and is fully compensated at the whole-heart level. This highlights the redundancy of RyR2 protein expression and the plasticity of the e-c coupling apparatus.

One-pot synthesis of phosphorylnaphth[2,1-d]oxazoles and products as P,N-ligands in C-N and C-C formation.

Phosphanylnaphtho[2,1-d]oxazoles were synthesized successfully through one-pot phosphonation of naphthoquinone with diaryl(alkyl)phosphine oxides and Cu-catalyzed oxidative condensation with imines, followed by methylation and reduction. Upon applying 4-phosphanylnaphtho[2,1-d]oxazole as a P,N-chelating ligand, Pd-catalyzed C-N formation of amines or nitrobenzene as well as Ni-catalyzed C-C formation and the synthesis of quinoline proceeded successfully. The reaction was facilely scaled up to give N-benzylaniline 15a in a gram scale synthesis. This research provided a facile and convenient protocol to synthesize phosphanylnaphtho[2,1-d]oxazoles, which could be applied as an efficient P,N-ligand in transition-metal-catalyzed C-N and C-C formation to produce the desired products in high yields with wide functional group tolerance under small catalyst loading, solvent-free conditions in many reactions.

Tunable laser frequency lock based on a temperature-dependent Fabry-Perot etalon.

A simple method for laser frequency stabilizing by a temperature-tuned Fabry-Perot etalon is reported. The etalon is a plano-convex lens that permits tuning the length and refractive index via controlling the temperature for shifting wavelengths in the region of 852 nm, with a transmission spectral linewidth of ∼72.5MHz and free spectral region of ∼16GHz. Using this scheme, arbitrary frequency locking of a laser with an adjustable frequency resolution of 2.34GHz/∘C is realized, and MHz-level long-term stability is demonstrated.

Glutamic Acid and Poly-γ-glutamic Acid Enhanced the Heat Resistance of Chinese Cabbage (Brassica rapa L. ssp. pekinensis) by Improving Carotenoid Biosynthesis, Photosynthesis, and ROS Signaling.

Heat stress is one of the most common agrometeorological risks in crop production in the middle and lower reaches of the Yangtze River in China. This study aimed to investigate whether glutamic acid (Glu) or poly-γ-glutamic acid (γ-PGA) biostimulants can improve the thermotolerance of a cool-season Chinese cabbage (Brassica rapa L. ssp. pekinensis) crop. Priming with Glu (2.0 mM) or γ-PGA (20 mg·L-1) was conducted at the third leaf stage by applying as daily foliar sprays for 5 days before 5 days of heat stress (45 °C in 16-h light/35 °C in 8-h dark). Coupled with morpho-physiological and biochemical analyses, transcriptomes of Glu or γ-PGA-primed Chinese cabbage under heat stress were examined by RNA-seq analysis. The results showed that the thermotolerance conferred by Glu and γ-PGA priming was associated with the increased parameters of vegetative growth, gas exchange, and chlorophyll fluorescence. Compared with the control, the dry weights of plants treated with Glu and γ-PGA increased by 51.52% and 39.39%, respectively. Glu and γ-PGA application also significantly increased the contents of total chlorophyll by 42.21% and 23.12%, and carotenoid by 32.00% and 24.00%, respectively. In addition, Glu- and γ-PGA-primed plants markedly inhibited the levels of malondialdehyde, electrolyte leakage, and super-oxide anion radical, which was accompanied by enhanced activity levels of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD). Enrichment analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) categories within the differentially expressed genes (DEGs) functional clusters of RNA-seq data indicated that the expression levels of the genes for DNA replication, DNA repair system, linoleic acid metabolism, cysteine and methionine metabolism, glutathione metabolism, purine and pyrimidine metabolism, carotenoid biosynthesis, and plant-pathogen interaction were commonly up-regulated by both Glu and γ-PGA priming. Glu treatment enhanced the expression levels of the genes involved in aliphatic glucosinolate and 2-oxocarboxylic acid, while γ-PGA treatment activated carotenoid cleavage reaction to synthesize abscisic acid. Taken together, both Glu and γ-PGA have great potential for the preadaptation of Chinese cabbage seedlings to heat stress, with Glu being more effective than γ-PGA.

Measurement of the permanent electric dipole moment of ultracold ground state 85Rb133Cs molecules by microwave coherent spectroscopy.

We demonstrate measurement of the permanent electric dipole moment (EDM) of 85Rb133Cs molecules in the absolute vibrational ground state by microwave (MW) coherent spectroscopy. The rotational states of the considered molecules, which are formed from short-range photoassociation of mixed cold atoms, are nondegenerated under external electric field. To measure the EDM based on electric-field-induced shifts of the sublevels of X1Σ+(v = 0, J = 1) rotational state, we utilized a MW coherent spectroscopy, which has a higher resolution than depletion spectroscopy and one-photon MW spectroscopy and can also eliminate the influence from Stark shift of the excited state existing in both spectroscopies above. In order to acquire accurate electric intensity, electromagnetic induced transparency spectroscopy of 85Rb Rydberg atoms is used to implement the calibration. The permanent EDM of 85Rb133Cs molecules is finally determined to be 1.266(15) D, which agrees with the theoretical calculations and is comparable with the value of its isotopic molecule.

Microwave-assisted coherent control of ultracold polar molecules in a ladder-type configuration of rotational states.

We demonstrate microwave-assisted coherent control of ultracold 85Rb133Cs molecules in a ladder-type configuration of rotational states. Specifically, we use a probe and a control MW field to address the transitions between the J = 1 → 2 and J = 2 → 3 rotational states of the X1Σ+(v = 0) vibrational level, respectively, and use the control field to modify the response of the probe MW transition by coherently reducing the population of the intermediate J = 2 state. We observe that an increased Rabi frequency of the control field leads to broadening of the probe spectrum splitting and a shift of the central frequency. We apply Akaike's information criterion (AIC) to conclude that the observed coherent spectral response appears across the crossover regime between electromagnetically induced transparency and Aulter-Townes splitting. Our work is a significant development in microwave-assisted quantum control of ultracold polar molecules with multilevel configuration.