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White phosphorus activation with low-valent metal species has proved to be very effective in converting P

In this work, nano carbon black was modified with polyethyleneimine (CB-PEI) under an ultrasonic field. The obtained product was used as a demulsifier to break oily wastewater. Morphology, structure, and chemical composition of CB-PEI were systematically analyzed. Bottle test was carried out to evaluate the influence of dosage, pH value and salinity on the demulsification efficiency of the emulsion. The results showed that the light transmittance of water phase (TSW) after the demulsification was 79.1% and corresponding oil removal rate (ORR) could reach up to 99.4% with 60 mg/L of CB-PEI at ambient temperature for 30 min. In addition, the possible demulsification mechanism was explored by dynamic interface tension (IFT), elasticity modulus, wettability, self-assemble of interfacial membrane, zeta potential and micrograph analysis. It indicated that CB-PEI had an appropriate amphiphilicity and good interfacial activity, which could improve it quickly transfer to the oil-water interface and result in the oil-water separation. The current work provides a simple method to prepare a demulsifier with excellent performance, so it has a good application prospect for the treatment of oil-water emulsions.

The traditional diagnosis model has great challenges for the etiological diagnosis of the central nervous system (CNS) diseases with similar clinical manifestations, especially for the diagnosis of rare pathogens. It is very important to make rapid and accurate identification of pathogens for guiding clinical choices in administering countermeasures.On August 22, 2020, a 49 years old Chinese male patient had a headache for two days, and then the computed tomography (CT) scan of the brain showed subarachnoid hemorrhage. Subsequently, he underwent twice craniotomy and about 3 weeks of hospitalization. Since September 20, the patient was in the local rehabilitation hospital for hyperbaric oxygen therapy for about three weeks. Then the patient developed acute purulent meningoencephalitis. In the absence of diagnosis of specific pathogenic bacteria, vancomycin (1 g every 12 hours), ceftazidime (2 g every 8 hours), mannitol dehydration (125 mL, every 8 hours), and sodium valproate (0.4 g tid) was used timely according to cerebrospinal fluid (CSF) examination and clinical manifestations. CSF smear and routine culture test were negative during hospitalization. We used the metagenomic next-generation sequencing (mNGS) analysis of CSF for quick and accurate diagnosis, which identified human herpesvirus type 4 (EBV), Corynebacterium corynebacterium, Achromobacter xylose oxidation, and Acinetobacter baumannii, But the mapping degree was not high. Then, we used the modified method-multiplex PCR-based targeted gene sequencing platform (ptNGS) to detect CSF samples and found that the sequences detected were Acinetobacter pittii (A. pittii) and Staphylococcus epidermidis. S. epidermidis might come from skin colonization during lumbar puncture, so it was excluded from the etiological diagnosis. Therefore, we highly suspected that A. pittii was the pathogen in this case. After about three weeks of hospitalization treatment, the patient's symptoms were relieved.In conclusion, empirical medication before the identification of pathogens is very important. The ptNGS may be an effective method for the diagnosis of pathogens.

Oily wastewater produced in the process of oil extraction has a potential threat to the environment. In this paper, diethylenetriamine was used to modify rice straw powder (RSP) by a solvent-free strategy, and the obtained product (AM-RSP) was utilized to dispose oily wastewater. AM-RSP was characterized by Field emission scanning electron microscope (FE-SEM), energy dispersive spectrometer (EDS), Fourier transform infrared spectroscope (FT-IR) and BET. The factors affecting the demulsification performance (DP) such as dosage, salinity and pH value were detailly investigated. The results indicated that light transmittance (E

In this paper, the high frequency characteristics of Trapezoidal Staggered Grating Slow-wave Structure for 1THz Traveling Wave Tube has been studied. The transmission structure has been simulated, the reflection coefficient is less than -20dB in the frequency of 1015GHz to 1055GHz and the loss of the structure is over 58dB. The PIC simulation shows that the saturation output power is 405mW at the frequency of 1030GHz, and the corresponding gain is 19.08dB.

Background: We conducted this systematic review and meta-analysis to investigate the clinical effect of dexmedetomidine in preventing pediatric emergence agitation (EA) or delirium (ED) following anesthesia compared with placebo or other sedatives.Methods: The databases of Pubmed, Embase, and Cochrane Library were searched until 8th January 2020. Inclusion criteria were participants with age

BACKGROUND: The cerebrospinal fluid (CSF) culture is a widely used method for the diagnosis of meningitis, but its detection sensitivity is low. Several new methods have been developed for pathogen detection, including metagenomic next-generation sequencing (mNGS) and pathogen-targeted NGS (ptNGS). In this study, we aimed to evaluate the performance of ptNGS in pathogen detection in CSF. METHODS: CSF specimens were acquired from 38 patients with meningitis who were diagnosed at Xuanwu Hospital, Capital Medical University between October 2020 and February 2021. DNA was extracted from the CSF samples, and pathogens were identified using both ptNGS and mNGS. SPSS 22.0 software was used to compare the pathogen detection performance of ptNGS and mNGS in CSF. RESULTS: Among the 38 patients with meningitis, 14 had a non-infectious disease (NID) and 24 had an infectious disease (ID). Of the 38 samples, both ptNGS and mNGS detected 9 (23.7%) positive samples, and 12 (31.6%) negative samples. Thirteen (34.2%) samples were detected to be positive by ptNGS only, and 4 (10.5%) were detected to be positive by mNGS only. The positivity rate detected by ptNGS for the ID group was higher than that detected by mNGS (P=0.080), and the positivity rates detected by ptNGS and mNGS for the NID group were comparable. The positive predictive value (PPV) and negative predictive value (NPV) of diagnosing an ID by ptNGS were 77.3% and 56.3%, respectively. While, the PPV and NPV of diagnosing an ID by mNGS were 76.9% and 44.0%, respectively. ptNGS increased the sensitivity rate by approximately 70%. The sensitivity rate of ptNGS was higher than that of mNGS (70.8% vs. 41.7%), while the specificity rate of mNGS was higher than that of ptNGS (78.6% vs. 64.3%). Additionally, ptNGS required a shorter time for pathogen diagnosis (15 vs. 24 hrs) and had lower costs than mNGS. CONCLUSIONS: ptNGS has a number of advantages over mNGS, including its sensitivity, timeliness, and economy, all factors that are important considerations in clinical use.

Using 1-ethylimidazole as ligand, a new zinc sulfite Zn(SO3)(C5N2H8) (1) has been synthesized under hydrothermal condition. Compound 1 shows two-dimensional layered structure constructed with triple-fused 4-rings (Zn4S4) motifs via corner-sharing oxygen atoms. The 12-MR windows are presented in the bc plane. The 1-ethylimidazole molecules are grafted onto the Zn atoms of two sides of this layer and the ethyl groups of the 1-ethylimidazole molecules exclusively protrude into the interlayer region. Alternating-current impedance analysis demonstrates compound 1 displays remarkable proton conductivity which relays on the relative humidity (RH). Under 98% RH, the value can reach up to 1.80 × 10−3 S cm−1 at 75 °C. The Ea is 0.52 eV at 98% RH, attributed to the vehicle mechanism by water molecules serving as proton carriers to carry protons.

Background. General anesthesia combining with a caudal block (CB) has been commonly performed in pediatric patients undergoing circumcision surgeries. However, some severe complications have been suspected of a caudal block in the combined use. To avoid these issues of a caudal block, this study introduces a novel dorsal penile nerve block (DPNB) via perineum guided by ultrasound as an alternative to a caudal block in pediatric circumcision surgeries. Methods. A total of 104 pediatric patients scheduled for circumcision surgeries were involved and randomly divided into 2 groups: the CB group (n=52) and the DPNB group (n=52). A laryngeal mask was inserted followed by induction and maintenance anesthesia of inhaled sevoflurane. In the DPNB group, a dorsal penile nerve block (DPNB) guided by a real-time ultrasonography was performed by a single injection via perineum of 0.25% ropivacaine plus 0.8% lidocaine with total injection volume of 3-5ml. In the CB group, a dose of 0.5 ml/kg was given via the caudal canal following the same general anesthesia with that of Group DPNB. The time to the first analgesic demand after surgery is the key data collected for comparing between the two study groups. Heart rates and respiratory rates changes before and during the surgical procedure, pain score when leaving the PACU, and the time taken for the first micturition after a surgery were also recorded to analyze the differences in analgesic effects between the CB and DPNB groups. Results. No significant difference in heart rates and respiratory rates was found between the two groups before and during the surgery. Pain scores were similar before pediatric patients leave the PACU. However, the time taken for the first micturition after a surgery in Group DPNB is shorter than Group CB. The patients in Group DPNB asked for analgesics later than those in Group CB. Additionally, no significant differences in adverse effects were noted between two groups except the numbness of the lower limbs occurring less in Group DPNB. Conclusions. The ultrasound-guided dorsal penile nerve block via perineal approach can basically act as a safe and effective alternative to the caudal block in pediatric patients undergoing circumcision surgeries. Clinical Trials identifier is ChiCTR-IPR-15006670. Protocol is available at http://www.chictr.org.cn/showproj.aspx?proj=11319.

A wideband coaxial line to double-ridge waveguide window for broadband high power THz TWT has been studied in this paper, which can cover the 270–370 GHz with a ultra-bandwidth over 0.1 THz. Based on the mode conversion theories and impedance matching techniques, the broadband transition of coaxial line to double ridge waveguide is designed. In addition, the diamond is adopted to design the broadband double ridged waveguide window. The characteristics of the transition are analyzed by using the full-wave analysis software. According to the simulated results, the reflection coefficient is less than −20 dB and the VSWR is less than 1.2 in the 270–370 GHz.

This paper reported a Q-band sheet beam slot-line backward wave oscillator (BWO). The characteristics of slot-line slow wave structure (SL-SWS) has been investigated and the result shows that it's much more suitable to be designed as a BWO than a traveling wave tube (TWT). The slot-line backward wave oscillator is driven by a 0.19A sheet beam whose rectangular cross section is 0.9mm*0.12mm. While the beam voltage ranges from 6000V to 10000V, the frequency of output signal varies from 40.275GHz to 43.925GHz, and the output power is over 40W.

Microbe-soil combined treatment is a newly developed technology in view of the defects of the curing process and waste drilling mud slag properties. In particular, 0.3%–0.5% bioremediation reagents were fully mixed with the waste drilling sludge according to its wet and dry degree, and 1.5 folds to twice weight of more finely ground soil was added in the mix, which was covered by soil of 5–15 cm thick and thereby grasses or greeneries were planted on the soil. The process was successfully applied to some fields of Well Danqian 001-8, Well Lianhua 000-X8, etc. After three months of such treatment, the main indexes of the drilling solid waste such as the degradation of COD and the oil-degrading ratio reached more than 90%, the index of leaching solution met the requirement of the first grade in the national “Integrated Wastewater Discharge Standard”; heavy metal ion concentration in soil did not change significantly with the indicators meeting the requirement of the third grade in the national “Soil Environmental Quality Standard” (Dry Land); and no harmful effects of heavy metals have ever been found on the planted grasses and greeneries. In conclusion, with this microbe-soil technology, the soil property will recover its background values without any other chemical additives, realizing the ecological restoration and reuse of land covered by wellsite wastes, so it is in line with the energy-saving and environmentally-friendly treatment way.

For a Voltage Source Converter based High Voltage Direct Current Transmission(VSC-HVDC)system the most important part is the VSC part because it determines main performance of the whole system. This paper proposed a new topology of PWM AC/DC converter which is cascaded VIENNA rectifier. In addition, in this paper a current controller based on the working modes of three-phase VIENNA rectifier will be introduced to control input currents. By this current controller the input currents can follow the corresponding references to achieve the goal of unit power factor. When this current controller is applied on the proposed cascaded VIENNA rectifier the performance will be investigated too. In order to verify the correctness of the current controller and the cascaded VIENNA rectifier, the prototype of three-phase VIENNA rectifier and single-phase two modules cascaded VIENNA rectifier are developed. The current controller and the proposed topology is validated by the way of analysis of the experimental results.

As a novel important regulator of glucose and lipid metabolism homeostasis, human fibroblast growth factor 21 (hFGF21) has become a potential drug candidate for the treatment of metabolic diseases including obesity, and type 2 diabetes, as well as non-alcoholic fatty liver disease. To improve the production of recombinant hFGF21 to meet the increasing demand in clinical applications, an artificial gene encoding its mature peptide sequence was constructed, cloned into vector pET-3c and then expressed in Escherichia coli Origami B (DE3). Under optimal conditions in a 50-L fermentor, the average bacterial yield and the soluble expression level of recombinant hFGF21 of six batches attained 1750 ± 185 g and 32 ± 1.5%, respectively. The target protein was purified by the combination of nickel-nitrilotriacetic acid affinity chromatography and Sephadex S-100 resin. 5% (w/v) trehalose solution was able to prevent rhFGF21 from degradation effectively. The purity of rhFGF21 was higher than 97%, and the yield was 213 ± 17 mg/L. The preliminary biochemical characterization of rhFGF21 was confirmed using Western blot and peptide map finger analysis. Based on the glucose oxidase-peroxidase assay, the EC50 of glucose uptake activity of the purified rhFGF21 was 22.1 nM.