Floquet Engineering Hz-Level Rabi Spectra in Shallow Optical Lattice Clock.

Quantum metrology with ultrahigh precision usually requires atoms prepared in an ultrastable environment with well-defined quantum states. Thus, in optical lattice clock systems deep lattice potentials are used to trap ultracold atoms. However, decoherence, induced by Raman scattering and higher order light shifts, can significantly be reduced if atomic clocks are realized in shallow optical lattices. On the other hand, in such lattices, tunneling among different sites can cause additional dephasing and strongly broadening of the Rabi spectrum. Here, in our experiment, we periodically drive a shallow ^{87}Sr optical lattice clock. Counterintuitively, shaking the system can deform the wide broad spectral line into a sharp peak with 5.4 Hz linewidth. With careful comparison between the theory and experiment, we demonstrate that the Rabi frequency and the Bloch bands can be tuned, simultaneously and independently. Our work not only provides a different idea for quantum metrology, such as building shallow optical lattice clock in outer space, but also paves the way for quantum simulation of new phases of matter by engineering exotic spin orbit couplings.

Feasibility of Brain Imaging Using a Digital Surround Technology Body Coil: A Study Based on SRGAN-VGG Convolutional Neural Networks.

Brain imaging using conventional head coils presents several problems in routine magnetic resonance (MR) examination, such as anxiety and claustrophobic reactions during scanning with a head coil, photon attenuation caused by the MRI head coil in positron emission tomography (PET)/MRI, and coil constraints in intraoperative MRI or MRI-guided radiotherapy. In this paper, we propose a super resolution generative adversarial (SRGAN-VGG) network-based approach to enhance low-quality brain images scanned with body coils. Two types of T1 fluid-attenuated inversion recovery (FLAIR) images scanned with different coils were obtained in this study: joint images of the head-neck coil and digital surround technology body coil (H+B images) and body coil images (B images). The deep learning (DL) model was trained using images acquired from 36 subjects and tested in 4 subjects. Both quantitative and qualitative image quality assessment methods were performed during evaluation. Wilcoxon signed-rank tests were used for statistical analysis. Quantitative image quality assessment showed an improved structural similarity index (SSIM) and peak signal-to-noise ratio (PSNR) in gray matter and cerebrospinal fluid (CSF) tissues for DL images compared with B images (P <.01), while the mean square error (MSE) was significantly decreased (P <.05). The analysis also showed that the natural image quality evaluator (NIQE) and blind image quality index (BIQI) were significantly lower for DL images than for B images (P <.0001). Qualitative scoring results indicated that DL images showed an improved SNR, image contrast and sharpness (P<.0001). The outcomes of this study preliminarily indicate that body coils can be used in brain imaging, making it possible to expand the application of MR-based brain imaging.

Standard-dose versus low-dose azathioprine in the treatment of Crohn's disease: A prospective randomized study.

OBJECTIVE: Azathioprine (AZA) is widely used to treat Crohn's disease (CD) with a recommended dose of 2-2.5 mg/kg per day for Westerners. Asian patients are suggested to take a lower dose. However, many clinicians reported poor efficacy with a reduced dose. This study aimed to explore a efficient and safe dose of AZA providing the best efficacy for Chinese CD patients. METHODS: Fifty patients with active CD were enrolled and randomized into two groups (n = 25 each). All other treatments were the same except that group A received 1 mg/kg per day and group B took 2 mg/kg per day of AZA. Complete remission (CR) rate and response rate at weeks 12, 24 and 48 were assessed by using intent-to-treat (ITT) and per-protocol (PP) analyses. Adverse events and recurrence rate were also evaluated. RESULTS: At week 48, CR rate and response rate in group B (ITT: 50.0% and 59.1%; PP: 57.9% and 68.4%) were significantly higher than those in group A (ITT: 13.0% and 17.4%; PP: 16.7% and 22.2%) (P < 0.05). Nine adverse events occurred, including pancreatitis (n = 1), arthritis (n = 2) and myelosuppression (n = 6). There was no significant difference in adverse events between the two groups. However, recurrence rate was significantly higher in group A than in group B (P = 0.042). CONCLUSION: AZA 2 mg/kg per day is more appropriate than 1 mg/kg per day for Chinese CD patients with a high efficacy, a low recurrence rate and not increased adverse events.

Synthesis of N-substituted acridinediones and polyhydroquinoline derivatives in refluxing water.

Acridinediones were synthesized by the one-pot Hantzsch condensation of an aromatic aldehyde, 5,5-dimethyl-1,3-cyclohexanedione, and aniline/4-methylaniline in refluxing water. This method has then been extended to the four-component reaction of an aromatic aldehyde, 5,5-dimethyl-1,3-cyclohexanedione, ethyl acetoacetate and ammonium acetate for the synthesis of polyhydroquinoline derivatives. This is an environmentally friendly and efficient procedure providing  good to excellent yields.

PTD4-apoptin protein and dacarbazine show a synergistic antitumor effect on B16-F1 melanoma in vitro and in vivo.

PTD4-apoptin protein enters cells and harbors tumor-selective cell death activity. Dacarbazine is the mainstay of treatment for malignant melanoma. In this study, we investigated the cytotoxic effect of PTD4-apoptin protein and/or dacarbazine in mouse B16-F1 and human A875 and SK-MEL-5 melanoma cells in vitro and by means of a mouse B16-F1 melanoma model in vivo. PTD4-apoptin protein inhibits the growth of B16-F1, A875 and SK-MEL-5 melanoma cells in a dose-dependent manner, but not in normal human cell lines WI-38 and L-02. PTD4-apoptin combined with dacarbazine revealed a synergistic cytotoxic effect (coefficient of drug interaction<1) in all three different tumor cell lines. In vivo, PTD4-apoptin protein and dacarbazine alone effectively inhibited the growth of B16-F1 melanoma in C57BL/6 mice. Strikingly, combined PTD4-apoptin/dacarbazine treatment significantly increased the antitumor effect in comparison to the single treatments. As important, a combined PTD4-apoptin/dacarbazine treatment with a 50% reduction of dacarbazine revealed similar antitumor activities, without detectable hematologic side effects. A combined PTD4-apoptin/dacarbazine treatment represents a promising novel efficient and safe anticancer strategy.

Investigation of biosurfactant-producing indigenous microorganisms that enhance residue oil recovery in an oil reservoir after polymer flooding.

Three biosurfactant-producing indigenous microorganisms (XDS1, XDS2, XDS3) were isolated from a petroleum reservoir in the Daqing Oilfield (China) after polymer flooding. Their metabolic, biochemical, and oil-degradation characteristics, as well as their oil displacement in the core were studied. These indigenous microorganisms were identified as short rod bacillus bacteria with white color, round shape, a protruding structure, and a rough surface. Strains have peritrichous flagella, are able to produce endospores, are sporangia, and are clearly swollen and terminal. Bacterial cultures show that the oil-spreading values of the fermentation fluid containing all three strains are more than 4.5 cm (diameter) with an approximate 25 mN/m surface tension. The hydrocarbon degradation rates of each of the three strains exceeded 50%, with the highest achieving 84%. Several oil recovery agents were produced following degradation. At the same time, the heavy components of crude oil were degraded into light components, and their flow characteristics were also improved. The surface tension and viscosity of the crude oil decreased after being treated by the three strains of microorganisms. The core-flooding tests showed that the incremental oil recoveries were 4.89-6.96%. Thus, XDS123 treatment may represent a viable method for microbial-enhanced oil recovery.

Aminobromination of olefins with TsNH(2) and NBS as the nitrogen and bromine sources mediated by hypervalent iodine in a ball mill.

A series of olefins including alpha,beta-unsaturated ketones, cinnamates, cinnamides and styrenes have been aminobrominated with good yields and excellent diastereoselectivities under mechanical milling conditions, using TsNH(2) and NBS as the nitrogen and bromine sources, promoted by (diacetoxyiodo)benzene.

Efficient preparation of aldoximes from arylaldehydes, ethylenediamine and Oxone in water.

The one-pot reaction of aromatic aldehydes, ethylenediamine and Oxone (2 KHSO5 x KHSO4 x K2SO4) in pure water was found to unexpectedly afford aldoximes in excellent yields.

[Glycosides from flowers of Jasminum officinale L. var. grandiflorum].

To study the chemical constituents of the flower of Jasminum officinale L. var. grandiflorum. The compounds were isolated and purified by re-crystallization and chromatography on silica gel and Sephadex LH-20 column. Their structures were elucidated on the physicochemical properties and spectral analysis. Seven glycosides were identified as kaempferol-3-O-alpha-L-rhamnopyranosyl (1-->3)-[alpha-L-rhamnopyranosyl (1-->6)]-beta-D-galactopyranoside (I), kaempferol-3-O-rutinoside (II), 7-ketologanin (III), oleoside-11-methyl ester (IV), 7-glucosyl-l1-methyl oleoside (V), ligstroside (VI), oleuropein (VII). Compound I is a new compound. Compounds III and V were isolated from the family of Jasminum for the first time and compounds II, IV and VI were isolated from Jasminum officinale L. var. grandiflorum for the first time.

Solvent-free mechanochemical and one-pot reductive benzylizations of malononitrile and 4-methylaniline using Hantzsch 1,4-dihydropyridine as the reductant.

Under mechanical milling conditions, direct reductive benzylizations of malononitrile and 4-methylaniline by aromatic aldehydes were achieved using a Hantzsch 1,4-dihydropyridine as the reductant.