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Background Severe acute hepatitis of unknown etiology in children has recently exhibited a global trend of concentrated occurrence. This review aimed to summarize the current available information regarding the outbreak of severe acute hepatitis and introduce our hospital’s previous experiences with the diagnosis and treatment of severe acute hepatitis for reference. Data sources Websites including the UK Health Security Agency, European Centre for Disease Prevention and Control, CDC, WHO, and databases including PubMed/Medline, Cochrane Library, Embase and Web of Science were searched for articles on severe acute hepatitis in children. Results As of May 26, 2022, a total of 650 cases have been reported in 33 countries; at least 38 (6%) children required liver transplantation, and nine (1%) died. Cases are predominantly aged between 3 and 5 years old, and there are no epidemiological links among them. The common manifestations are jaundice, vomiting and pale stools. Adenovirus tested positive in most cases, and SARS-CoV-2 and other viruses were detected in a few cases, but virus particles were not found in liver tissue. Adenovirus immunohistochemistry showed immunoreactivity in the intrasinusoidal lumen from some liver samples. The hierarchical treatment includes symptomatic and supportive therapy, management of coagulation disorders and hepatic encephalopathy, artificial liver support, and liver transplantation (approximately 6%–10% of cases require liver transplant). Conclusions The etiology of this severe acute hepatitis in children is not clear. The clinical features are severe acute hepatitis with significantly elevated liver enzymes. Clinicians need to be alert to children with hepatitis.

A robust and highly active homogeneous chiral nickel-phosphine complex for the asymmetric hydrogenation of aliphatic γ- and δ-ketoacids has been discovered. The hydrogenation could proceed smoothly in the presence of 0.0133 mol% catalyst loading (S/C=7500). The coordination chemistry and catalytic behavior of Ni(OTf)

Phyllanthus emblica L. pomace is a waste residue obtained following juicing that contains many polyphenols. In this study, NKA-II resin was selected as the optimal macroporous resin for separation and employed to separate the crude polyphenol extract of P. emblica pomace. The separation conditions were optimized, and the polyphenol content, polyphenol components, antioxidant activity, and potential anti-Alzheimer's effects of the extract were measured before and after purification. Results showed that the polyphenol content of the purified extract was 656.85 mg/g, which was 2.1 times higher than that of the nonpurified form. Further, the polyphenol components of the pomace, which was like that of the fruit, did not vary after purification. The antioxidant activity of the purified extract was also significantly improved. Moreover, purified extract significantly reduced the paralysis rate of the transgenic Caenorhabditis elegans model of Alzheimer's disease, and the mechanism was related to maintenance of redox homeostasis. PRACTICAL APPLICATION: The polyphenol content and antioxidant activity of purified polyphenol from Phyllanthus emblica L. pomace extracts were significantly improved using optimal separation methods with NKA-II macroporous resin and 70% aqueous ethanol as the eluent in this study. Moreover, purified polyphenols showed potential effects in alleviating Alzheimer's disease. These results suggest that polyphenols separated from P. emblica pomace are valuable for further research and development, and the utilization rate of P. emblica fruit is improved due to the further development of P. emblica pomace.

Shot peening (SP) is one kind of effective mechanical surface treatment to improve the surface mechanical property. Increasing SP intensity can not only introduce compressive residual stresses into the layer near the treated surface, but also produce nanocrystalline layer near the treated surface. This paper investigated the method of predicting the generation of refined grains after high energy shot peening (HESP) proposed by previous works. In that method, the equivalent plastic strain (PEEQ) was considered as a critical value for estimating the grain refinement level. The main contribution of this paper was to prove the applicability of the proposed method of predicting nanostructured surface layer in different HESP conditions via a HESP model with different numbers of shots and impact patterns. The simulated results show the ultimate PEEQ value is independent of the element size in all HESP conditions, which confirms this method is a practical and effective tool to evaluate surface nanocrystallization phenomenon during HESP process.

Spot continual induction hardening (SCIH) is one kind of selective surface treatments, which has been proven to be appropriate for improving the tribological property and the fatigue behavior of specific areas of treated components. In our work, an electromagnetic-thermal-mechanical-metallurgical coupled numerical model was developed based on a novel co-simulation of ANSYS and ABAQUS/standard via making use of these two commercial finite element softwares' respective advantages to describe the SCIH process. The simulated results agreed well with experimental data in temperature development and the distributions of hardness, phase and residual stresses. The relationship between the inductor velocity and surface characteristics was discussed and the optimization of induction coil velocity was carried out based on the validated numerical model.

The aim of this study was to compare nasogastric (NG) feeding with nasojejunal (NJ) feeding when treating pediatric patients with acute pancreatitis (AP).We performed a single-center, prospective, randomized, active-controlled trial involving 77 pediatric patients with AP from April 2014 to December 2017. The patients were randomized into two groups: the NG tube feeding group (34 patients) and the NJ tube feeding group (33 patients). The primary outcome measures included the enteral nutrition intolerance, the length of tube feeding time, the recurrent pain of pancreatitis and complications.A total of 62 patients with AP (31 patients for each group) came into the final analysis. No differences were found in baseline characteristics, pediatric AP score and computed tomography severity score between the two groups. Three (9.7%) patients in the NG group and one (3.2%) patient in the NJ group developed intolerance (relative risk = 3.00, 95% confidence interval 0.33-27.29, P = 0.612). The tube feeding time and length of hospital stay of the NG group were significantly shorter than those of the NJ group (P = 0.016 and 0.027, respectively). No patient died in the trial. No significant differences were found in recurrent pain, complications, nutrition delivery efficacy, and side effects between the two groups.NG tube feeding appears to be effective and safe for acute pediatric pancreatitis compared with NJ tube feeding. In addition, high qualified, large sample sized, randomized controlled trials in pediatric population are needed.

Objective To analyze and compare the effects of peri-treatment analgesics on acute and chronic pain and postoperative functional recovery of patients with thoracolumbar fractures, so as to guide the clinical drug use. Methods Seven hundred nineteen patients with thoracolumbar fractures were collected and divided into acetaminophen dihydrocodeine, celecoxib, and etoricoxib groups. The main indicators were the degree of postoperative pain (visual analog scale (VAS)), the incidence of chronic pain and postoperative functional recovery (Oswestry dysfunction index (ODI) and Japanese Orthopedics Association score (JOA)), which were continuously tracked through long-term telephone follow-up. The correlation analysis of ODI-pain score, peri-treatment VAS score, and ODI index was performed, and bivariate regression analysis was conducted to understand the risk factors for chronic pain. Results Regression analysis showed that severe spinal cord injury and peri-treatment use of acetaminophen dihydrocodeine were both one of the risk factors for postoperative chronic pain. But there were no statistically conspicuous differences in basic characteristics, preoperative injury, and intraoperative conditions. Compared with the other two groups, patients in the acetaminophen dihydrocodeine group had longer peri-therapeutic analgesic use, higher pain-related scores (VAS 1 day preoperatively, VAS 1 month postoperatively, and ODI-pain 1 year postoperatively), higher VAS variation, higher incidence of chronic pain 1 year after surgery, and higher ODI index. And other ODI items and JOA assessments showed no statistically significant differences. In addition, the correlation analysis showed that the peri-treatment pain score was correlated with the severity of postoperative chronic pain. Conclusion Although the peri-treatment analgesic effect of acetaminophen dihydrocodeine is good, it is still necessary to combine analgesics with different mechanisms of action for patients with severe preoperative pain of thoracolumbar fracture, so as to inhibit the incidence of postoperative chronic pain and improve the quality of postoperative rehabilitation.

We report the spatiotemporal mode-locked multimode fiber laser operating at 1.55 µm based on semiconductor saturable absorber mirrors with the mode-locking threshold as low as 104 mW. Benefiting from the multimode interference filtering effect introduced in the laser cavity not only the central wavelength can be continuously tuned from 1557 nm to 1567 nm, but also the number of the output pulses can be adjusted from 1 to 4 by simply adjusting the polarization controllers. This work provides a new platform for exploring the dynamic characteristics of spatiotemporal mode-locked pulses at negative dispersion regime. Moreover, this kind of tunable laser has potential applications in fields of all-optical signal processing, fiber sensing and information coding.

We report a switchable and spacing tunable dual-wavelength spatiotemporal mode-locked (STML) laser based on the multimode interference filtering effect in an all-fiber linear cavity. The dual-wavelength STML operations combined with different pulse patterns are achieved. By adjusting the polarization controllers, the dual-wavelength STML pulses can be switched to single wavelength operation, which is tunable up to 35 nm under certain pump powers. Moreover, the dual-wavelength spacing can also be tuned from 8 nm to 22 nm. The obtained results contribute to understanding and exploring the spatiotemporal characteristics operating in the multi-wavelength regime of STML fiber lasers. All-fiber STML lasers with lasing wavelength tunability and flexibility may have applications in the fields of optical communications and optical measurements.

Previously, we have demonstrated that policosanol from Chinese wax suppressed testosterone(T)-induced alopecia in mice. However, the underlying mechanism remained to be determined. Herein, we investigated the mechanism of policosanol against androgenetic alopecia (AGA). AGA was induced in Kunming mice by subcutaneous administration of testosterone propionate for 60 d. Policosanol (0.5 %, 1% or 2%) was applied topically on the back of mice. Finasteride (2%) was applied topically as a positive control. The serum T and estradiol (E2) concentrations were determined by ELISA after 28 and 60 days of treatment. The cutaneous expression or activity of key mediators of hair growth, such as alkaline phosphatase (ALP), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF), was measured. MTS assay was performed to evaluate cell proliferation in cultured human dermal papilla cells (DPCs) treated with dihydrotestosterone (DHT). Western blotting was performed to evaluate the protein expression of Bax, Bcl2, TGF-β2, caspase-9, and caspase-3. We found lower T and T/E2 ratio in mice treated with policosanol than in the model group. Policosanol suppressed premature hair follicle entry into the regression phase, as shown by improving VEGF and EGF expression and ALP activity. The MTS assay showed that policosanol markedly inhibited the apoptosis of DHT-treated DPCs. Western blotting showed that policosanol significantly reduced the protein expression of TGF-β2, cleaved caspese-9, cleaved caspase-3, and Bax, and increased that of Bcl2. The optimal effect was obtained with 12.50 g/mL policosanol. In conclusion, policosanol prevents androgenetic alopecia by regulating hormone levels and suppressing premature hair follicle entry into the regression phase.

Background Alzheimer’s disease (AD), an age-related neurodegenerative disorder and a serious public health concern, is mainly caused by β-amyloid (Aβ)-induced toxicity. Currently, a limited number of drugs are effective against AD, and only a few are used for its treatment. According to traditional Chinese medicine, white wax is mainly composed of policosanol, hexacosanol, and octacosanol. Policosanol has been shown to reduce lipid levels in blood and alleviate the symptoms associated with diabetic complications and neurodegenerative disorders, such as Parkinson’s disease and AD. However, the efficacy of policosanol depends on the purity and composition of the preparation, and the therapeutic efficacy of policosanol derived from insect wax (PIW) in AD is unknown. Methods Here, we identified the main components of PIW and investigated the effects of PIW on Aβ-induced toxicity and life-span in a transgenic Caenorhabditis elegans model of AD, CL4176. Furthermore, we estimated the expression of amyloid precursor-like protein (apl-1) and the genes involved in various pathways associated with longevity and alleviation of AD-related symptoms in PIW-fed CL4176. Results PIW mainly consists of tetracosanol, hexacosanol, octacosanol, and triacontanol; it could decrease the Aβ-induced paralysis rate from 86.87 to 66.97% (P P apl-1, a gene known to be associated with the levels of Aβ deposits in C. elegans. Additionally, our results showed that PIW modulated the expression of genes associated with longevity-related pathways such as heat shock response, anti-oxidative stress, and glutamine cysteine synthetase. Conclusion Our findings suggest that PIW may be a potential therapeutic agent for the prevention and treatment of AD. However, its effects on murine models and patients with AD need to be explored further.

In order to investigate the effect of shot peening (SP) on residual stress distribution of AISI 304 stainless steel, a 3D dynamic model for describing single and multiple shot impact phenomenon was...

In order to investigate the recrystallization behavior of peened surface deformation layer of precipitation hardening stainless steel, a classic x-ray diffraction line profile analysis, Voigt method, was carried out on peened 17-4PH with different isothermal annealing temperatures. The activation energy of domain boundary migration (Qa) and the activation energy of microstrain relaxation (Qb) were calculated by regression analysis in different annealing temperature conditions. The results show that the value of Qa decreases with annealing temperature increasing, which is due to the influence of precipitation (e-Cu) size on the movements of grain and subgrain boundaries. The maximum growth rate of e-Cu particles occurs during 400 to 500 °C interval. Compared with growth behavior of domain size, microstrain relaxation behavior is less sensitive to precipitation particle size. The effects of annealing temperature and time on dislocation density are both significant when annealing temperature is lower than 500 °C. However, the effect of annealing temperature on dislocation density becomes insignificant when annealing temperature is higher than 500 °C. 300 °C annealing temperature only leads to the microstrain relaxation but nearly cannot lead to the domain size growth even if prolonging annealing time. Microstructure enhancement effect still exists in plastic deformation layer when 300 °C annealing temperature lasts for 60 min but nearly disappears when 600 °C annealing temperature lasts for 20 min.

Porosity and particle arrangement are important parameters affecting soil tortuosity, so it is of great significance to determine the intrinsic relationship between them when studying soil permeability characteristics. Theoretical derivation and geometric analysis methods are used to derive a two-dimensional geometric tortuosity model. The model is a function of particle arrangement parameters (m and θ) and porosity. An analysis of the model and its parameters shows that: (1) The arrangement of particles is one of the reasons for the different functional relationship between tortuosity and porosity, which proved that the tortuosity is not only related to the porosity but also affected by the particle arrangement. (2) The greater the anisotropy parameter m is, the greater the tortuosity is, indicating m varies when fluid passes through the soil from different sides resulting in different values of permeability. (3) The tortuosity increases with the increase in the blocking parameters θ. (4) With increasing porosity, the influence of the parameters m and θ on the tortuosity gradually decreases, suggesting that the influence of particle arrangement on tortuosity gradually decreases. The results presented here increase the understanding of the physical mechanisms controlling tortuosity and, hence, the process of fluid seepage through soil.

As an important mean of shot peening (SP) research, finite element simulation has been widely and successfully employed in estimating the surface characteristic and residual stress distribution after SP treatment. In this study, the effects of shot overlap and rigid body assumptions on dimple geometry and residual stress distribution in depth were discussed via the validated ordered dimple pattern and stochastic dimple pattern SP models for quenched and tempered 42CrMo steel. The results show that shot overlap assumption has a great influence on the surface plastic deformation of peened material. The simulated value of plastic deformation is much larger than the experimental value, which results in the residual stress of the overlapping shot SP model deviating from the actual result seriously. For the prediction of the residual stress distribution, the shot must be set as an elasto-plastic body when the number of shot is large. The shot can be set as a rigid body for the aim of reducing the calculation time when the number of shots is small. In addition, the influence of material hardness on residual stress and equivalent plastic strain (PEEQ) was investigated via simulating the residual stress and PEEQ of different hardness materials treated by SP process.

We report the spatial beam self-cleaning in bi-tapered conventional multimode fibers (MMFs) with different tapered lengths. Through the introduction of the bi-tapered structure in MMFs, the input beam with poor beam quality from a high-power fiber laser can be converted to a centered, bell-shaped beam in a short length, due to the strengthened nonlinear modes coupling. It is found that the bi-tapered MMF with longer tapered length at the same waist diameter shows better beam self-cleaning effect and larger spectral broadening. The obtained results offer a new method to improve the beam quality of high-power laser at low cost. Furthermore, it may be interesting for manufacturing bi-tapered MMF-based devices to obtain the quasi-fundamental mode beam in spatiotemporal mode-locked fiber lasers.