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High-TC superconductor thin film heterostructures were deposited using reactive co-evaporation for dual layer electronic applications. The epitaxial structure consisted of 35-nm YBa2Cu3O7-δ(YBCO), 75-nm CeO2 , 150-nm YBCO, and 20-nm CeO2 on r-plane sapphire wafers. The critical temperature was measured to be 83.6 K and 84.8 K for the bottom and top YBCO layers, respectively. Atomic force microscopy reveals smooth surfaces with RMS roughness of the top YBCO layer to be 4.7 nm. The CeO2 insulating layer exhibited hopping conduction that freezes out at low temperature, making these structures suitable for electrical circuits with isolated ground planes.

Focused helium ion beam material modification is ideally suited for the fabrication of YBa2Cu3O7-δ (YBCO) Josephson junctions and superconducting feature sizes down to the nanoscale. We report the fabrication and measurement of YBCO nano-slit SQUIDs and study how scaling the dimensions of the SQUID body and electrodes influences the electrical properties. Sixteen nano-slit SQUIDs with different width and length were fabricated from a single-layer 25-nm-thick YBCO film. The experimental results yield an estimation of the sheet inductance to be ∼4 pH/□ and a penetration depth of ∼180 nm. The temperature dependence of the inductance agree well with an impurity scattering model, indicating that the TC of the film was ∼82 K, and the ratio between geometric inductance and kinetic inductance at 0 K was ∼0.8. These results provide solid basis for the design of high-performance, high-TC micro-SQUID magnetometers.

Objective To investigate the influence of thoracic paravertebral block(TPVB) and serratus anterior plane block(SAPB) on postoperative analgesia and stress response in patients with breast cancer. Methods A total of 92 patients who planned to receive radical mastectomy from January 2020 to December 2021 in Huizhou Municipal Central Hospital were selected as study objects. All the patients were divided into SAPB group(SAPB + laryngeal mask general anesthesia, n=31), TPVB group(TPVB + laryngeal mask general anesthesia, n=31) and general anesthesia group(laryngeal mask general anesthesia, n=30) according to random number method. The postoperative pain and analgesic effect were compared among the three groups. The stress response indexes ［interleukin(IL)-10, IL-6 and malondialdehyde(MDA)］before and 24 hours after operation were compared among the three groups. The adverse reactions of the three groups were recorded. Results The VAS scores at 12 h, 24 h, 48 h and 72 h after operation were as follows: simple anesthesia group＞SAPB group＞TPVB group(P＜0.05). The dosage of sufentanil and the effective press times of patient-controlled intravenous analgesia(PCIA) within 48 hours after operation were as follows: simple anesthesia group＞SAPB group＞TPVB group(P＜0.05). The levels of serum IL-10, IL-6 and MDA at 24 h after operation were as follows: simple anesthesia group＞SAPB group＞TPVB group(P＜0.05). Conclusion TPVB is superior to SAPB in postoperative analgesia for breast cancer, which can effectively relieve postoperative pain of patients, prolong the effective duration of analgesia, reduce the dose of analgesic drugs, and alleviate the stress reaction of the body.

Antibiotic residues in milk powder are public focusing concerns relevant to food safety. Long term exposure to antibiotic residues will lead to drug resistant strains in human body, reduce body's immunity, and bring health hazards to consumers. Sulfonamides, (fluoro)quinolones and macrolides are high frequency detecting antibiotic residues in matrix of milk powder. Rapid screening analysis of these residues and simultaneous confirmation with high confidence are valuable in practical scenarios of investigation testing, special monitoring program and so on. The direct analysis in real time (DART) ion source is an emerging technology of ambient pressure desorption ionization, it can directly complete the analysis of sample ionization and injection at the ambient pressure and open experimental environment, without changing the properties of the analyte itself. It became possible to analyze samples directly with minimal sample preparation steps or even without any sample pretreatment procedure with DART ion source. A hybrid high resolution mass spectrotmety, quadrupole orbitrap high resolution mass spectrometry (Q-Orbitrap HRMS) is a powerful tool in veterinary drug residue analysis with superior specificity, accuracy and sensitivity. In present study, DART ion source was hyphenated to Q-Orbitrap HRMS to perform rapid screening analysis and simultaneously unambiguous identification of the above mentioned antibiotic residues in milk powder. Sample was diluted in water and fast purified by filtering solid phase extraction column and then the filtrate was subjected to DART QOrbitrap HRMS analysis. Several key parameters of the DART ion source, such as ionization type and temperature, as well as injection speed of DART ion source were optimized to enhance the performance of the method. Then, a QuickStrip (QS) Module was selected with the helium as carrier gas and ionization temperature as well as injection speed were set to 400 ℃ and 1 mm/s, respectively. The DART ion source with optimized settings coupled to Q-Orbitrap HRMS was finally applied to screening analysis. Results showed that 16 commonencountered antibiotic residues including sulfonamides, (fluoro)quinolones and macrolides can be effectively detected with the screening concentration of 100 μg/kg. Recoveries of the analytes ranged from 72.5% to 106.7% and the false negative rates were all less than 5%. Real life sample analysis was finally conducted by the proposed method with an expected method performance, evidencing the potency of the developed method in risk monitoring in milk powder for veterinary drug screening analysis. It should be mentioned here that the screening concentration of 100 μg/kg is a compromised concentration for the sake of some less sensitive analytes to provide reliable determination of the antibiotic residues with the proposed procedures. It is, however, quite meaningful concentration to indicate the existence of high risk level of corresponding antibiotic residues which need to take actions. In total, the proposed method can play a role in risk monitoring laboratories and relevant industry institutions.

In order to develop a soft composite with high‐performance puncture resistance and self‐healing property property, herein, we introduced Pluronic F127 diacrylate (F127DA) into titania‐based nanocomposite hydrogels (PAMT) and then compounded hydrogel and aramid fabric to form gel‐matrix soft composites (GMSCs). The result shows that, with the addition of 5 wt% TiO2 nanoparticles, the hydrogels exhibited a fracture strain of 3898%, a toughness of 12.23 MJ/m3 and a self‐healing efficiency of 99.45% after healing at 100°C for 12 h, indicating multiple recycling feature. In addition, a series of mechanical tests had shown that the resultant GMSCs exhibited incredible spike puncture resistance and knife puncture resistance, 17.66 times and 13.78 times greater than that of pure fabrics, and could achieve 33.84% spike puncture self‐healing efficiency and 26.62% knife puncture self‐healing efficiency. The synergetic reinforcement mechanism of the hydrogel and fabrics was also analyzed. This study provides a valuable reference for designing a puncture resistant soft composite with rapid self‐healing and repeated recycling. [ABSTRACT FROM AUTHOR]

What is known and objective: Propofol and esketamine are routine anaesthetics used in sedation or general anaesthesia for paediatric procedures. Coadministration could reduce the dose of either propofol or esketamine required and lower the incidence of drug‐related adverse events. We designed a four‐arm randomized controlled trial in children undergoing diagnostic upper gastrointestinal endoscopy to investigate the dose of propofol with different doses of esketamine inducing appropriate depth of anaesthesia in 50% patients (median effective dose, ED50). Methods: After getting the approval of the research ethics committee and informed consent, 92 paediatric patients planning for upper gastrointestinal endoscopy were divided into four groups randomly: esketamine 0, 0.25, 0.5 and 1 mg/kg groups (n = 23/group). Propofol doses followed the Dixon and Massey up‐and‐down method with different starting and interval doses between groups. During the first attempt of endoscope insertion, if patients' reactions prevented the insertion, it would be considered as a failure. The awakening time, total propofol doses, as well as the perioperative and post‐procedure adverse events were evaluated and recorded for each patient. Results and discussion: The ED50 (median, 95% confidence interval) of propofol was significantly greater in esketamine 0 and 0.25 mg/kg groups in comparison with the esketamine 0.5 and 1 mg/kg groups (4.1 [3.3–4.9]; 3.1 [2.5–3.8] mg/kg vs. 1.8 [1.1–2.4]; 0.8 [0.2–1.3] mg/kg, respectively, p <.05). The total doses of propofol in esketamine 0.5 and 1 mg/kg groups were statistically lower than these in esketamine 0 and 0.25 mg/kg group (p <.01). The mean blood pressure was lower in the esketamine 0 mg/kg group than that in 1 mg/kg group after administration and during the procedure (p <.01). The esketamine 1 mg/kg group showed a higher incidence of vomiting and visual disturbances than the other three groups (p <.001). What is new and conclusion: In children who accomplished diagnostic paediatric upper gastrointestinal endoscopy under deep sedation/anaesthesia, the total dosage of propofol needed was reduced significantly in esketamine 0.5 and 1 mg/kg groups with a corresponding reduce in propofol‐related hemodynamic changes. However, a higher incidence of esketamine‐related adverse effects was found in esketamine 1 mg/kg group. [ABSTRACT FROM AUTHOR]