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To evaluate potential viral contamination on the surfaces of personal protective equipment (PPE) in COVID-19 wards.Face shields, gloves, the chest area of PPE and shoe soles were sampled at different time points. The samples were tested for the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by PCR, and the cycle threshold (CT) values were recorded.The positive rate was 74.7% (239/320) for all PPE specimens. The CT values of the samples were ranked in the following order: face shieldschestsglovesshoe soles (37.08±1.38, 35.48±2.02, 34.17±1.91 and 33.52±3.16, respectively; P for trend.001). After disinfection, the CT values of shoe soles decreased compared with before disinfection (32.78±3.47 vs. 34.3±2.61, P = .037), whereas no significant effect of disinfection on the CT values of face shields, chests and gloves was observed. After disinfection, the CT values of specimens collected from shoe soles gradually increased; before disinfection, the CT values of shoe sole specimens were all less than 35.SARS-CoV-2 can attach to the surfaces of the PPE of healthcare professionals in COVID-19 wards, especially the shoe soles and undisinfected gloves. Shoe soles had the highest SARS-CoV-2 loads among all tested PPE items.

BackgroundFatigue and long work hours of surgeons attracts increasing concerns in recent years. In clinical practice, most patients prefer to receiving surgery in the morning. So, we aimed to explore whether starting time is associated with perioperative outcomes and hospital cost for elective lung surgery. MethodsA retrospective study was conducted on elective lung surgery patients between September 2019-November 2019. Patients were divided into “early start group” if surgery started before 4pm while “late start group” was after 4pm. Perioperative outcomes and total hospital costs were compared between two groups. Besides, multivariable logistic regression analysis was performed for further analysis.ResultsA total of 398 patients were finally enrolled for analysis in this study. Of all the cases, 295 patients were divided into early start group while 103 patients belonged to late start group. There were no differences in postoperative hospital duration, operation time, complication incidence and total hospital cost. In multivariable logistic regression analysis, surgery start late was still found not to be a risk factor.ConclusionIn elective lung surgery, perioperative outcomes and cost were all similar between early start and late start surgery, it was not necessary to worry about surgery order for these patients.

Background The effect of general anesthetics (propofol and volatile anesthetics) on pulmonary outcome after lung resection surgery with one-lung ventilation (OLV) is yet undetermined. We evaluated the effect of intravenous anesthesia (propofol) and volatile anesthesia (sevoflurane or desflurane) regimens on postoperative pulmonary complications (PPCs) in patients undergoing lung resection surgery. Methods This prospective, randomized controlled trial enrolled 555 adult patients scheduled for lung resection surgery with OLV. Participants were randomized to 1 of 3 general anesthetic regimens (propofol, sevoflurane, or desflurane). Standard anesthesia and ventilation protocols were followed in all groups. The primary outcome was a composite of PPCs in the first 7 postoperative days. Secondary outcomes included the severity of PPCs and major postoperative complications classification. Intergroup difference in the primary outcome was assessed for significance using the Pearson χ2 test. Results Of 837 patients who were assessed for eligibility, 555 were randomized and 545 were analyzed. One hundred and seventy-nine patients were assigned to the propofol group, 182 in the sevoflurane group, and 184 in the desflurane group. The incidence of PPCs did not differ between the combined volatile anesthetics (sevoflurane and desflurane) group and the propofol group (21.9% vs 24.0%; odds ratio, 0.89; 95% confidence interval, 0.58-1.35; P = .570). The PPCs grade and Clavien-Dindo scores did not differ significantly across groups. Conclusions In patients undergoing lung resection surgery with OLV, general anesthesia with volatile anesthetics (sevoflurane or desflurane) did not reduce PPCs compared with propofol. No difference in secondary outcomes was observed.

To investigate the correlations of serum homocysteine (Hcy), α2-Heremans-Schmid glycoprotein (AHSG), and C-reactive protein (CRP) with insulin resistance (IR), 25-hydroxyvitamin D (25-OH-VD), and blood lipids in patients with gestational diabetes mellitus (GDM) by detecting their levels.A total of 72 GDM patients (GDM group) and 72 healthy pregnant women (control group) delivered in our hospital from February 2017 to January 2019 were randomly selected. The basic data, somatological parameters [height, weight, body mass index (BMI), waist circumference, hip circumference, waist-to-hip ratio (WHR), blood pressure, and body fat content], and biochemical indexes (glucose metabolism indexes, lipid metabolism indexes, Hcy, AHSG, CRP, and 25-OH-VD) were compared between the two groups. Additionally, Pearson's correlation analysis was employed to analyze the correlations among indicators.In comparison with the control group, the GDM group had a higher average rate of family history of DM (p0.05), larger waist circumference and WHR, and higher body fat content (p0.05). Besides, the fasting plasma glucose (FPG), 1-hour plasma glucose (1hPG) and 2-hour plasma glucose (2hPG), glycosylated hemoglobin (HbA1c), fasting insulin (FINS), homeostasis model assessment (HOMA)-IR, triglyceride (TG), total cholesterol (TC), and low density lipoprotein cholesterol (LDL-C) were higher in the GDM group than those in the control group (p0.05), while the high density lipoprotein cholesterol (HDL-C) was lower in the GDM group than that in the control group (p0.05). Compared with those in the control group, the serum Hcy, AHSG, and CRP levels rose, while the serum 25-OH-VD level declined in the GDM group (p0.05). The results of Pearson's correlation analysis revealed that HOMA-IR had positive correlations with FPG, FINS, TC, TG, Hcy, AHSG, and CRP (r = 0.591, 0.825, 0.312, 0.234, 0.458, 0.647, 0.487, p0.05) and negative correlation with 25-OH-VD (r = -0.323, p0.05). CRP was positively correlated with HOMA-IR, TC, and AHSG (r = 0.485, 0.331, 0.226, p0.05), negatively associated with 25-OH-VD (r = -0.443, p0.05), and had no correlation to TG and Hcy (r = 0.019, 0.058, p0.05). AHSG displayed positive correlations with HOMA-IR, TC, TG, and CRP (r = 0.647, 0.321, 0.314, 0.226, p0.05) and no association with Hcy and 25-OH-VD (r = 0.058, -0.034, p0.05).GDM patients have increased serum Hcy, AHSG, and CRP levels and a decreased serum 25-OH-VD level, indicating that serum Hcy, AHSG, CRP, and 25-OH-VD are correlated with glucose and lipid metabolism disorders in GDM patients.

Relying on 1 × 2 photonic crystal waveguide and photonic crystal resonator, a compact eight-channel terahertz wave power splitter is proposed. The mechanism of such a device is further theoretically analyzed and numerically investigated with the aid of the plane wave expansion method and the finite-difference time-domain method. With an appropriate design, the proposed power splitter can split the input terahertz wave energy equally into eight output ports at the frequency of 0.667 THz. Furthermore, the total size of the present device is of 4.33 mm × 3.74 mm. Due to its small size, the multi-channel terahertz wave power splitter has practical applications in the terahertz wave integrated circuit fields.

Ontology technology is the foundation of the semantic Web, and provides support for the definition of domain ontology to the clothing e-commerce direct knowledge base, so as to realize the electronic commerce platform based on domain knowledge. In this paper, the design of the clothing network marketing e-commerce platform is an integrated product sales, product management, marketing and sales information entrance, marketing, customer relationship management and other functional modules operating platform. The paper presents application of ontology technology in building knowledge base of e-commerce system in direct selling clothing network. Experimental results show that the proposed application technology has high efficiency.

In this article, a method for simultaneously enhancing the gain and reducing the size of microstrip antennas using a spiral complementary openings resonance ring (CSRR) structure ground plane has been presented. The proposed antenna is successfully designed and measured, which provides frequency band from 5.145∼5.387 GHz. By adjusting the size of the spiral CSRR on the ground plane, small size antenna of 25 × 25 × 0.8 mm3 and 5.8 dBi of relative high gain are achieved. Comparing the simulated and measured results confirm the suitability of the proposed antenna for wireless local area network application. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:117–120, 2014

An equivalent circuit model is proposed to estimate the absorbance characteristics of the proposed terahertz wave absorber based on metamaterial. The component can be optimized to achieve high absorption of different frequency of the incident electromagnetic wave by adjusting physical dimensions and material parameters. The fabricated device was characterized by using a Fourier transform infrared spectrometer. The designed absorber demonstrated excellent absorbance compared with previously reported metamaterial-based terahertz wave absorbers, which exhibited 99.3% absorbance at 0.575 THz. The simulation and measurement results show that the absorber is an excellent terahertz wave collector. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2195–2198, 2013

We present an ultra-compact gate-voltage-controlled terahertz power divider based on graphene plasmonic waveguide, which consists of five graphene ribbons embedded in the polymethylmethacrylate (PMMA) substrate. We have theoretically explained their mechanisms as bias voltage change induced carrier density of graphene modification and the coupling coefficients of graphene plasmon effect after carrier density change, respectively. The surface plasmonic polariton (SPP) propagation and extinction ratio in the graphene-based device are numerically investigated. The proposed terahertz power divider has a 3dB working band about 0.1THz and its extinction ratio reaches about 39.86dB at the frequency of 7THz. It anticipated that our proposed compact device is potentially interesting for the terahertz wave integrated circuit technology.

We proposed a simple scheme to manipulate the position of the reflected terahertz wave beam based on the prism/liquid crystal structure. Both the stationary-phase method and finite element method are used to analyze and simulate the characteristics of the proposed device. To give comprehensive understanding, the position of the reflected terahertz wave beam is verified in simulation by using the COMSOL Multiphysics software. Numerical calculation results show that the proposed terahertz wave switch a high extinction ratio (35dB for TE polarization and 30dB for TM polarization). This provides an attractive way for creating a simple structure and compact size terahertz wave switch with acceptable extinction ratio.

Modifications of the interfacial electrical characteristics of kaolin were investigated through reversing particles surface charges induced by organic cationic polyelectrolyte and natural anionic organic substance. Zeta potential and rheology tests indicated that polymeric OH-Al reversed the edge charges and reached a saturation adsorption on kaolin surface at dosage of 45μmol/g, corresponding to a lower viscosity of kaolin suspension, as a result of the combined action of OH-Al modified positive particle surface and negative charges from sodium hexametaphosphate dispersant. A significant reduction in viscosity of kaolin modified by gallic acid was also observed in either dilute or concentrated suspension. The strong interaction of OH-Al ions with clay greatly increased the gallic acid adsorption, and resulted in the lowest viscosity for modified kaolin, indicating the bound of gallic acid to the reactive surface sites induced by OH-Al. It can be concluded in this experiments that the highly charged organic coating play a role in the dispersion of kaolin particles.

In this work, the possibility of diluting chemicals using white water in paper making process instead of fresh water was discussed. The circulation water was found to be harmless to the fines and filler retention when retention aids chemicals were prepared with fresh water. The retention performance of the dual retention aids system consisting of CPAM and bentonite was determined when dissolved using white water. It was found that the dissolution of CPAM with white water from disc saveall did not have an influence on the efficiency of retention aids system, while the flocculation function of bentonite was significantly affected by the quality of white water. Moreover, the result indicated that it was feasible for fixing agent PEI to be dissolved with white water in this experiment.

To analyze the distribution of the higher order aberrations in the population of Chinese with myopia and astigmatism and determine whether the pupil size, degree of myopia and astigmatism affects the higher order aberrations.Using a Tscherning method, 147 myopic and astigmatism eyes were evaluated before LASIK. The root mean square (RMS) values of higher order aberrations for each subject with pupil diameters of 4.5, 5.0, 5.5, 6.0, 6.5 and 7.0 mm were calculated. The subjects were divided into following groups: high myopia (-6.00 D) and low myopia (or= -6.00 D); astigmatism group I (or= 0.75 D) and astigmatism group II (0.75 D).The root mean square (RMS) values was decreased from 3rd order to sixth order aberrations in the same eye. The individual difference was from 6.1-fold to 36.6-fold in same type of aberration. All types of aberrations, in particular spherical and coma aberration, was increased significantly with increasing pupil size. Secondary spherical aberration, spherical and secondary coma aberration were affected by myopia, but coma aberration; astigmatism only affected the coma aberration, but spherical aberration.The aberrations were increased with the increasing of refractive error such as myopia and astigmatism. Spherical aberration is more common in high myopia, Coma aberrations is related with astigmatism.