Search

Background: Coronavirus disease 2019 (COVID-19) has been a great concern since 2019. Patients with myasthenia gravis (MG) may be at higher risk of COVID-19 and a more severe disease course. We examined the associations between COVID-19 and MG. Methods: This single-center retrospective cohort study involved 134 patients who were diagnosed with MG from June 2020 to November 2022 and followed up until April 2023. They were divided into a COVID-19 group and non-COVID-19 group. Logistic regression analysis was used to detect factors potentially associating COVID-19 with MG. Results: Of the 134 patients with MG, 108 (80.6%) had COVID-19. A higher number of comorbidities was significantly associated with an increased risk of COVID-19 (p = 0.040). A total of 103 patients (95.4%) had mild/moderate COVID-19 symptoms, and 4 patients (3.7%) were severe/critical symptoms (including 2 deaths). Higher age (p = 0.036), use of rituximab (p = 0.037), tumors other than thymoma (p = 0.031), Hashimoto's thyroiditis (p = 0.011), more comorbidities (p = 0.002), and a higher baseline MG activities of daily living (MG-ADL) score (p = 0.006) were risk factors for severe COVID-19 symptoms. The MG-ADL score increased by ≥ 2 points in 16 (15.7%) patients. Dry cough and/or expectoration (p = 0.011), use of oral corticosteroids (p = 0.033), and use of more than one kind of immunosuppressant (p = 0.017) were associated with the increase of the post-COVID-19 MG-ADL score. Conclusion: Most patients with MG have a mild course of COVID-19. However, patients with older age, many comorbidities, a high MG-ADL score, and use of a variety of immunosuppressants during COVID-19 may be more prone to severe symptoms. [ABSTRACT FROM AUTHOR]

A cobalt-based alloy coating was prepared on the surface of 300 M steel using magnetic field-assisted laser cladding technology. The effects of different frequencies of an alternating magnetic field on the properties of the coating, such as the microstructure, phase characteristics, mechanical properties, thermal stress, and wear and corrosion resistance were investigated. The results showed that the electromagnetic field optimized the microstructure of the coating, and the microstructural refinement was most significant at a magnetic field of 65 Hz. As the magnetic field frequency increased, the degree of microstructural refinement decreased. Modification of the magnetic field frequency did not produce any change in the phase composition of the laser cladding coating. However, the application of a magnetic field reduces the thermal expansion coefficient and elastic modulus of the coating, thus decreasing its thermal stress. The laser cladding coating formed in a magnetic field exhibited enhanced resistance to wear and corrosion. In particular, the coating formed in a magnetic field with a frequency of 65 Hz exhibited a lower friction coefficient and less surface plastic deformation. Further, the corrosion resistance of the coating improved significantly owing to the magnetic field effect, leading to a substantial improvement in the mechanical performance of the laser cladding coatings. [ABSTRACT FROM AUTHOR]

Considering that curved space-time in coordinate or momentum representation should be curved, this paper proposes a new high-order generalized uncertainty principle by modifying the coordinate and momentum operator simultaneously, which could give a self-consistent phenomenological explanation for the existence of the minimum observable length. Moreover, using the proposed new high-order generalized uncertainty principle, we can deduce not only the minimum observable length, but also the allowable maximum observable momentum. More importantly, we further use the new generalized uncertainty principle to discuss the functional analysis of the position operator and maximum localization states, the compare the results with the existing literature. Finally, the harmonic oscillator is further discussed as an example. [ABSTRACT FROM AUTHOR]

In this paper, the effects of laser power, spot diameter, and scanning speed on the performance of laser cladding NiCrBSi alloy coating on 42CrMo steel substrate were studied, and nine orthogonal experiments were designed for experiment. The experimental data of OM morphology, microstructure, microhardness and wear property of coating were analyzed by using the methods of visual analysis and range analysis. The results show that laser power is the main factor affecting the height of the cladding coating. The spot diameter has the largest effect on the width of the cladding coating. The scanning speed has a significant effect on the depth of the molten pool. The laser power has the greatest influence on the microhardness and wear resistance of the cladding coating. As the laser power increases, the microhardness of the cladding coating decreases. The wear forms of the cladding coating are mainly abrasive and adhesive wear. [ABSTRACT FROM AUTHOR]

Background: Severe developmental dysplasia of the hip is a surgical challenge. The purpose of this study is to describe the cementless arthroplasty with a distal femoral shortening osteotomy for Crowe type IV developmental hip dysplasia and to report the results of this technique. Materials and Methods: 12 patients (2 male and 10 female) of Crowe type IV developmental hip dysplasia operated between January 2005 and December 2010 were included in the study. All had undergone cementless arthroplasty with a distal femoral shortening osteotomy. Acetabular cup was placed at the level of the anatomical position in all the hips. The clinical outcomes were assessed and radiographs were reviewed to evaluate treatment effects. Results: The mean followup for the 12 hips was 52 months (range 36-82 months). The mean Harris hip score improved from 41 points (range 28-54) preoperatively to 85 points (range 79-92) at the final followup. The mean length of bone removed was 30 mm (range 25-40 mm). All the osteotomies healed in a mean time of 13 weeks (range 10-16 weeks). There were no neurovascular injuries, pulmonary embolism or no infections. Conclusion: Our study suggests that cementless arthroplasty with a distal femoral shortening is a safe and effective procedure for severe developmental dysplasia of the hip. [ABSTRACT FROM AUTHOR]

Curcumin is a polyphenolic bioactive compound in turmeric. We examined if antioxidant effects of curcumin are associated with lifespan extension in Drosophila. In this experiment, females and males of Drosophila were fed diets either containing no curcumin (C0) or supplemented with curcumin at 0.5 (C1) and 1.0 (C2) mg/g of diet. The levels of malondialdehyde (MDA), enzyme activity of superoxide dismutase (SOD), and expression of seven age-related genes in females and males were analyzed. We found that C1 and C2 increased mean lifespan by 6.2 % and 25.8 % in females, and by 15.5 % and 12.6 % in males, respectively. Meanwhile, C1 and C2 significantly decreased MDA levels and increased SOD activity in both genders. Diets C1 in females and C2 in males are effective in extending mean lifespan and improving levels of two physiological and biochemical measures related to aging in Drosophila. Lifespan extension of curcumin in Drosophila was associated with the up-regulation of Mn-SOD and CuZn-SOD genes, and the down-regulation of dInR, ATTD, Def, CecB, and DptB genes. The present results suggest that curcumin increases mean lifespan of Drosophila via regulating gene expression of the key enzyme SOD and reducing accumulation of MDA and lipid peroxidation. This study provided new insights for understanding the anti-aging mechanism of curcumin in Drosophila. [ABSTRACT FROM AUTHOR]

The hydrogenated amorphous silicon (a-Si:H) thin films were prepared by plasma enhanced chemical vapor deposition at various substrate temperatures. This paper examined the relationship between structural evolution and electronic states of the tested thin films. Raman spectroscopy was used to evaluate the structural evolution in amorphous network. Meanwhile, Fourier transform infrared spectroscopy was applied to explore the change of hydrogen in thin films. Results show that the order of network on short and intermediate scales, the content and bonding mode of bonded hydrogen, as well as the intrinsic stress and silicon coordination defects, and closed rings in the thin films, vary with the deposition temperature. The dielectric spectra of samples were measured using SE850 spectra ellipsometer. The density of electronic band states (DOS) in both valence band and conduction band for a-Si:H thin films was obtained by fitting the measured dielectric spectra. The results, verified by optical measurement, reveal that the effect of hydrogenation on band edge DOS is predominant in comparison with that of network relaxation. [ABSTRACT FROM AUTHOR]

In the present study, we express the quality, function, and characteristics of architecture to help people comprehensively understand what architecture is. We also reveal the problems and conflict found in population, land, water resources, pollution, energy, and the organization systems in construction. China's economy is transforming. We should focus on the cities, architectural environment, energy conservation, emission-reduction, and low-carbon output that will result in successful green development. We should macroscopically and microscopically analyze the development, from the natural environment to the artificial environment; from the relationship between human beings and nature to the combination of social ecology in cities, and farmlands. We must learn to develop and control them harmoniously and scientifically to provide a foundation for the methods used in architecture research. [ABSTRACT FROM AUTHOR]

Abstract  A new dual simultaneous detector was developed for capillary electrophoresis microchip. Confocal laser-induced fluorescence (LIF) and moveable contactless conductivity detection (MCCD) were combined together for the first time. The two detection systems shared a common detection cell and could respond simultaneously. They were mutually independent and advantageous in analyses of mixtures containing organic and inorganic ions. The confocal LIF had high sensitivity and the MCCD could move along the separation channel and detect in different positions of the channel. The detection conditions of the dual detector were optimized. Rhodamine B was used to evaluate the performance of the dual detector. The limit of detection of the confocal LIF was [ABSTRACT FROM AUTHOR]

Abstract  An odorant-binding protein cDNA (Acer-ASP2) was cloned and characterized from antennae of adult workers of an Asian honey bee, Apis cerana cerana F. (Hymenoptera: Apidae). The full-length open reading frame of Acer-ASP2 cDNA was 429 bp, encoding 142 amino acids. Protein signature analyses revealed that it contained six conserved cysteines with an N-terminal signal sequence of 19 amino acids. The deduced protein sequence shares high homology with Amel-ASP2 from the honey bee, Apis mellifera L., and low similarity with odorant-binding proteins from other species of insects. Immunocytochemical localization showed that Acer-ASP2 was concentrated in the lymph of olfactory sensilla, such as sensilla placodea and sensilla trichodea A. Real-time polymerase chain reaction of Acer-ASP2 transcripts showed that Acer-ASP2 was expressed on antennae but not in other general anatomical regions of the body. Temporally, Acer-ASP2 was expressed at a relatively high level in adults during two periods (9 and 27 vs. 1, 15, and 30 days). This timing is correlated with the production of beeswax and searching behavior for nectar/pollen, respectively. Thus, Acer-ASP2 is a species-specific gene that we propose to be involved in the acquisition of odorant molecules from nectar, pollen, and other general odorant sources. [ABSTRACT FROM AUTHOR]

The adsorption of a surfactant mixture, based on an anionic surfactant, sodium dodecyl benzenesulfonate (SDBS) and a nonionic surfactant (Triton X-100, or TX100), on alumina nanoparticles was determined by solution depletion method combined with spectrometric measurement. It is shown that the light scattering, originated from the residual adsorbent alumina particles in the supernatant after centrifugation separation, interferes with the measurements of absorbance of the surfactant molecules, and therefore constitutes an error source for determination of the surfactant concentration in the supernatant by spectrometric means. The intensity of this light scattering, namely the influence of the residual alumina nanoparticles upon the surfactant adsorption, was related to the surfactant adsorption and its equilibrium concentration and varied among a batch. In this paper we report a Kalman filter method in order to eliminate the variational scattering background caused by non-separated residual alumina nanoparticles in each supernatant. This method is of interest as it is simple, easy to carry out and of high precision. [ABSTRACT FROM AUTHOR]

In this paper, we prove that the weak solutions $$ u \in W^{{1,p}}_{{{\text{loc}}}} {\left( \Omega \right)}{\left( {1 < p < \infty } \right)} $$ of the following equation with vanishing mean oscillation coefficients A( x): belong to $$ W^{{1,q}}_{{{\text{loc}}}} {\left( \Omega \right)}{\left( {\forall q \in {\left( {p,\infty } \right)}} \right)} $$, provided $$ F \in L^{q}_{{{\text{loc}}}} {\left( \Omega \right)} $$ and B( x, u, h) satisfies proper growth conditions, where Ω ⊂ R N ( N ≥ 2) is a bounded open set, A( x) = ( A ij( x)) N× N is a symmetric matrix function. [ABSTRACT FROM AUTHOR]

Abstract. The genetic diversity, relationship and molecular identification of 15 well known, widely planted traditional Chinese elite tea genetic resources [Camellia sinensis (L.) O. Kuntze] preserved in the China National Germplasm Hangzhou Tea Repository in the Tea Research Institute of the Chinese Academy of Agricultural Sciences located in Zhejiang province, China, were investigated using RAPD markers. A total of 1050 bands with an average of 52.5 bands per primer, 70 bands per genetic resource were generated by the 20 selected primers from the 15 tea genetic resources. In the total of 137 amplified products, 129 were polymorphic, corresponding to 94.2% genetic diversity. The relative frequency of polymorphic products was from 0.24 to 0.83, with an average of 0.47. In general, this average frequency was relatively high. The genetic distances among the genetic resources were from 0.16 to 0.62, with an average of 0.37. The 15 tea genetic resources were grouped into three groups by UPGMA cluster analysis based on RAPD data. By using the presence of 20 unique RAPD markers and the absence of 11 unique markers, all the 15 investigated tea genetic resources could be easily identified. RAPD markers provided a practical method not only to evaluate the genetic diversity and relationship, but also to identify tea genetic resources. [ABSTRACT FROM AUTHOR]

In this paper, using capacity theory and extension theorem of Lipschitz functions we first discuss the uniqueness of weak solution of nonhomogeneous quasilinear elliptic equations in space W ( θ, p)(Ω), which is bigger than W (1, p)(Ω). Next, using revise reverse Hölder inequality we prove that if ω c is uniformly p-think, then there exists a neighborhood U of p, such that for all t ∈ U, the weak solutions of equation corresponding t are bounded uniformly. Finally, we get the stability of weak solutions on exponent p. [ABSTRACT FROM AUTHOR]

Based on the conductivity change produced by the urea/urease reaction, a piezoelectric enzyme sensor is applied to the detection of urea in urine. The influence of the variation in solution temperature on frequency measurement is greatly reduced by using a buffer giving solution conditions with a near-zero frequency temperature coefficient for the sensor. The sum of the frequency shifts over the reaction time was used to increase the sensitivity of the determination. The linear range of the method is 1–30 μg/ml for urea, with RSDs of 1–2.6%. The detection limit is 0.01 μg/ml. [ABSTRACT FROM AUTHOR]