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In this paper, the alkali sulfadiazine neodymium (NdSD) was prepared from sulfadiazine and neodymium nitrate hexahydrate under alkaline conditions, and used as a heat stabilizer on PVC. The structure of NdSD was characterized by elemental analysis and infrared spectrum. The results show that the molecular formula of NdSD is Nd (SD)2·OH·H2O. The thermal degradation process of NdSD at 25-800°C was characterized by thermogravimetric analysis. The results show that the decomposition temperature of NdSD is higher than 200°C, which is suitable for PVC thermal stabilizer. The thermal stabilizer time of PVC by NdSD was characterized by static Congo red method. The results showed that the thermal stabilizer time of PVC increased from 2.7min to 23.2 min after adding NdSD. The discoloration effect of NdSD on PVC was characterized by oven discoloration method. The results indicate that PVC samples added with NdSD show better effect than other heat stabilizers. By means of silver nitrate solution method and Fourier transform infrared spectroscopy, it was proved that sulfadiazine neodymium can absorb and react with HCl, and further proposed a possible mechanism of NdSD stabilization of PVC.

The contents and correlation of various mineral elements in soil and roots, stems and leaves of Fritillaria hubeiensis were analyzed and evaluated to supply basis for diagnosis of soil mineral nutrition and rational fertilization of Fritillaria hubeiensis. The contents of Phosphorus, potassium, calcium, magnesium, iron, zinc, manganese and copper were tested by the inductively coupled plasma, and the results were analyzed by SPSS11.5 software. The total contents of manganese, phosphorus, potassium, calcium and magnesium in soil and roots, leaves and stems of Fritillaria hubeiensis were different with different cultivation bases. The order of Fe and Cu contents was root > leaf > stem. The distribution of Zn showed a trend of “root > stem > leaf.” Between potassium content of soil and root, it was a significant positive correlation. But there was a significant negative correlation between Zinc content of soil and root. The total contents of calcium and iron were positively correlated between roots and stems. The total contents of Phosphorus, potassium, magnesium and copper were positively correlated among stems and leaves, while the contents of Mn were positively correlated. Therefore, Fritillaria hubeiensis mainly regulates the amount of mineral nutrients through selective absorption.

Thymocytes bearing autoreactive T cell receptors (TCRs) are agonist-signaled by TCR/co-stimulatory molecules to either undergo clonal deletion or to differentiate into specialized regulatory T (Treg) or effector T (Teff) CD4+ cells. How these different fates are achieved during development remains poorly understood. We now document that deletion and differentiation are agonist-signaled at different times during thymic selection and that Treg and Teff cells both arise after clonal deletion as alternative lineage fates of agonist-signaled CD4+CD25+ precursors. Disruption of agonist signaling induces CD4+CD25+ precursors to initiate Foxp3 expression and become Treg cells, whereas persistent agonist signaling induces CD4+CD25+ precursors to become IL-2+ Teff cells. Notably, we discovered that transforming growth factor-β induces Foxp3 expression and promotes Treg cell development by disrupting weaker agonist signals and that Foxp3 expression is not induced by IL-2 except under non-physiological in vivo conditions. Thus, TCR signaling disruption versus persistence is a general mechanism of lineage fate determination in the thymus that directs development of agonist-signaled autoreactive thymocytes.

Nickel oxide deposited silica stationary phase was prepared by liquid phase deposition and characterized. Its chromatographic performance was evaluated using several compounds such as typical polar compounds and benzimidazoles as probes. The effects of mobile phase variables such as acetonitrile content, salt concentration, and pH on the chromatographic behavior, thermodynamics, and kinetics of these compounds were investigated to reveal the retention mechanism. The results showed that the prepared stationary phase exhibited a retention behavior of hydrophilic interaction liquid chromatography, and that multiple retention mechanisms including partitioning, adsorption, ion-exchange, electrostatic attraction, and coordination interactions contributed to solute retention. The coordination of nickel oxide electron-accepting sites and the electron-donating solutes resulted in the mixed-mode retention on stationary phase, which could be very useful for enhancing the chromatographic selectivity for the analytes. The batch-to-batch reproducibility was acceptable with the relative standard deviations of probe retentionof less than 9.89%. The prepared nickel oxide deposited silica stationary phase was successfully employed for the separation of several compounds, and it showed better separation effect and different selectivity from silica column and commercial Zorbax NH2 column.

Background During the past decades, robotic-assisted technology has experienced an incredible advancement in the field of total joint arthroplasty (TJA), which demonstrated promise in improving the accuracy and precision of implantation and alignment in both primary total hip arthroplasty (THA) and total knee arthroplasty (TKA). However, revision TJA remains a technically challenging procedure with issues of large-scale bone defects and damage to nearby anatomical structures. Thus, surgeons are trying to harness the abilities of robotic-assisted technology for revision TJA surgery. Methods PubMed, Embase, Cochrane Library, and Google Scholar were comprehensively searched to identify relevant publications that reported the application of robotic-assisted technology in revision TJA. Results Overall, ten studies reported the use of the robotic system in revision TJA, including active (ROBODOC) and semi-active (MAKO and NAVIO) systems. One clinical case reported conversion from hip fusion to THA, and three studies reported revision from primary THA to revision THA. Moreover, four studies reported that robotic-assisted technology is helpful in revising unicompartmental knee arthroplasty (UKA) to TKA, and two case reports converted primary TKA to revision TKA. In this study, we present the latest evolvements, applications, and technical obstacles of robotic-assisted technology in the revision of TJA and the current state-of-the-art. Conclusion Current available evidence suggests that robotic-assisted technology may help surgeons to reproducibly perform preoperative plans and accurately achieve operative targets during revision TJA. However, concerns remain regarding preoperative metal artifacts, registration techniques, closed software platforms, further bone loss after implant removal, and whether robotic-assisted surgery will improve implant positioning and long-term survivorship.

Unconstrained optimization problems often arise from mining of big data and scientific computing. On the basis of a modified gradient-difference, this article aims to present a new three-term conjugate gradient algorithm to efficiently solve unconstrained optimization problems. Compared with the existing nonlinear conjugate gradient algorithms, the search directions in this algorithm are always sufficiently descent independent of any line search, as well as having conjugacy property. Using the standard Wolfe line search, global and local convergence of the proposed algorithm is proved under mild assumptions. Implementing the developed algorithm to solve 750 benchmark test problems available in the literature, it is shown that the numerical performance of this algorithm is remarkable, especially in comparison with that of the other similar efficient algorithms.

Most existing convolutional neural-network-based super-resolution (SR) methods focus on designing effective neural blocks but rarely describe the image SR mechanism from the perspective of image evolution in the SR process. In this study, we explore a new research routine by abstracting the movement of pixels in the reconstruction process as the flow of fluid in the field of fluid dynamics (FD), where explicit motion laws of particles have been discovered. Specifically, a novel fluid micelle network is devised for image SR based on the theory of FD that follows the residual learning scheme but learns the residual structure by solving the finite difference equation in FD. The pixel motion equation in the SR process is derived from the Navier-Stokes (N-S) FD equation, establishing a guided branch that is aware of edge information. Thus, the second-order residual drives the network for feature extraction, and the guided branch corrects the direction of the pixel stream to supplement the details. Experiments on popular benchmarks and a real-world microscope chip image dataset demonstrate that the proposed method outperforms other modern methods in terms of both objective metrics and visual quality. The proposed method can also reconstruct clear geometric structures, offering the potential for real-world applications.

The overall scale and proportion of the aging population in China is on the rise. The rate of population aging is further accelerated. The trend of advanced aging is increasingly obvious. This study analyzes the current situation and causes of the aging population and proposes specific solution paths and strategies. The authors suggest reducing the impact of population aging by encouraging childbirth to fundamentally increase the number of newborns population, actively promoting the policy of delaying retirement, and building a redistribution system compatible with an aging society. Society is suggested to accelerate the establishment of a sound social security system and to reduce the stereotype of the aged. Applying modern science and technology and better public policies can improve the quality of services for the elderly. These suggestions in this paper provide a reference for improving the social work of the elderly, which is conducive to improving the quality of life and happiness index of the elderly.

Reproducing physically-based global illumination (GI) effects has been a long-standing demand for many real-time graphical applications. In pursuit of this goal, many recent engines resort to some form of light probes baked in a precomputation stage. Unfortunately, the GI effects stemming from the precomputed probes are rather limited due to the constraints in the probe storage, representation or query. In this paper, we propose a new method for probe-based GI rendering which can generate a wide range of GI effects, including glossy reflection with multiple bounces, in complex scenes. The key contributions behind our work include a gradient-based search algorithm and a neural image reconstruction method. The search algorithm is designed to reproject the probes' contents to any query viewpoint, without introducing parallax errors, and converges fast to the optimal solution. The neural image reconstruction method, based on a dedicated neural network and several G-buffers, tries to recover high-quality images from low-quality inputs due to limited resolution or (potential) low sampling rate of the probes. This neural method makes the generation of light probes efficient. Moreover, a temporal reprojection strategy and a temporal loss are employed to improve temporal stability for animation sequences. The whole pipeline runs in realtime (>30 frames per second) even for high-resolution (1920×1080) outputs, thanks to the fast convergence rate of the gradient-based search algorithm and a light-weight design of the neural network. Extensive experiments on multiple complex scenes have been conducted to show the superiority of our method over the state-of-the-arts.

Solar still is a simple equipment for the fresh water production in the regions where water is scarce and is rich in solar energy sources. In this paper, a solar still unit was built and tested in the south of China to investigate its water production. The test results show that the fresh water production is affected by average solar irradiation intensity, the production of the unit averaged at 6.27 kg/day, the water production decreased to 1.9 kg/day when the daily average solar radiation decreased to 236 W/m2. At the same time, the test result show that because of the difference between the ambient and seawater temperatures, the solar still could produce water at night, and the daily production could increase to 7.55 kg/day when the daily average solar radiation is 533 W/m2.

In this work, the composite electrode composed of metal-organic frameworks and transition metal phosphides is first assembled on the nickel foam substrate. The as-prepared NiCo-MOF-74@Ni

Obesity hypoventilation syndrome (OHS) is frequently misdiagnosed and undertreated, increasing the risk of perioperative complications. We aimed to determine the predictors of OHS and to develop and validate a novel nomogram and online calculator for identifying patients at risk of OHS in bariatric surgery candidates.We retrospectively analyzed the data of patients undergoing bariatric surgery between March 2017 and June 2020. Predictors were identified using univariate and multivariate analyses to establish the nomogram. The discriminative ability, calibration, and clinical value of the nomograms were tested using C-statistics, calibration plots, and decision curve analysis. The nomogram was internally validated using bootstrap resampling.A total of 577 patients were enrolled, and OHS was presented in 17.9% (103/577). Body mass index (BMI) (odds ratio [OR], 1.11; 95% confidence interval (CI), 1.04-1.18; p = 0.001), neck circumference (OR, 1.09; 95% CI, 1.01-1.18; p = 0.035), type 2 diabetes (T2D) (OR, 2.02; 95% CI, 1.17-3.45; p = 0.011), serum bicarbonate (OR, 1.47; 95% CI, 1.30-1.67; p 0.001), and C-reactive protein (CRP) (OR, 1.03; 95% CI, 1.01-1.06; p = 0.017) were independent risk factors for OHS and incorporated to develop the nomogram. The nomogram revealed good discrimination, with a C-index of 0.830 (95% CI: 0.784-0.876) (0.8227 through internal validation), and good calibration. Decision curve analysis further confirmed the nomogram's clinical usefulness.The novel nomogram and online calculator provided an excellent preoperative individualized prediction of OHS in patients undergoing bariatric surgery, hereby potentially assisting clinicians and surgeons in the early detection and intensive monitoring of OHS.

Our study aims to develop a diagnostic model using 24-h intraocular pressure (IOP) patterns to differentiate between open-angle glaucoma (OAG) and dysthyroid optic neuropathy (DON) in thyroid eye disease (TED) patients with glaucoma-like symptoms.TED patients with elevated IOP, abnormal optic disc, and/or visual fields were prospectively recruited. The subjects whose symptoms were relieved by DON first-line treatments were divided into the DON group, and the subjects with previous diagnosis of OAG before TED onset were divided into the OAG group. The 24-h IOP was monitored by Tono-Pen in a sitting position during awake time and in a supine position during sleep time. All subjects were divided into a training set and a testing set. The diagnostic models were generated from training set by using either IOP curve-derived parameters or principal component (PC) factors. The discrimination ability was tested in training set based on area under curve (AUC), and the calibration ability was verified in testing set by Hosmer-Lemeshow goodness-of-fit. The sensitivity and specificity were calculated by two-by-two table with the cutoff value determined by Youden's index.Thirty-two cases were recruited in each group. The 24-h IOP curves revealed a nocturnal pattern in both groups, with the acrophase moving slightly forward in the DON group (21:00 pm-24:00 pm) compared to the OAG group (22:00 pm-3:00 am). Several IOP curve-derived parameters differed between the two groups, with larger amplitude during sleep time (P 0.000) and longer duration of IOP ≥ 21 mmHg at awake time (P = 0.004) in the DON group than the OAG group. However, the diagnostic model generated from IOP parameters showed poor reliability (P = 0.001) in calibration test and was rejected. The other model built on PC factors achieved good performance of discrimination (AUC = 0.943) and calibration (P = 0.139) with a sensitivity of 87.50% and a specificity of 95.83% at cutoff value of 0.538 to identify OAG cases.The diagnostic model facilitates discrimination between OAG and DON in TED patients based on 24-h IOP-related patterns.This work was registered on Chinese Clinical Trial Registry (ChiCTR1900025394).