Search

High repetition frequency (HRF) ultrashort pulse fiber laser has been widely used in laser cold processing. The technical solutions such as short cavity length fiber laser have been proposed to achieve HRF ultrashort pulse output recently. However, the application of material-based saturable absorbers in this field has been astricted due to the low modulation depth, low damage resistance threshold, and high saturation fluence. Here, we designed a one-dimensional asymmetric photonic crystal with defect layer (1D-APCDL) as a novel saturable absorber, where the defect layer is Bi1.6Sb0.4Te3 with high modulation depth. The harmonic pulse with 3.82 GHz repetition frequency is achieved at the wavelength of 1562 nm, which is the highest repetition frequency of the topological insulator-based ring fiber laser so far to the best of our knowledge. The research provides a new saturable absorber solution, and provides a new idea for the application of material-based nonlinear optical chip in high-repetition frequency ultrashort pulse fiber lasers.

Background Papillary thyroid carcinoma is the most common thyroid carcinoma worldwide. Papillary thyroid carcinoma metastasis to the cervical region increases the probability of local or regional recurrence and the requirement for further surgery. Contrast-enhanced ultrasound has been suggested as a possible adjunct diagnostic technique for evaluating papillary thyroid carcinoma metastatic lymph nodes in several studies. This meta-analysis aims to evaluate the diagnostic accuracy of contrast-enhanced ultrasound for cervical lymph nodes metastatic in papillary thyroid carcinoma patients. Methods A search for studies evaluating the role of contrast-enhanced ultrasound for assessing cervical lymph nodes metastatic in papillary thyroid carcinoma patients from January 2000 to May 2022 was performed in PubMed, Embase, OVID, and Web of Science databases. The Quality Assessment of Diagnostic Accuracy Studies 2 evaluated the quality of the studies. All analyses were performed using Review Manager 5.3 and Stata 17.0. Results A total of seven articles were finally included in this study. Perfusion type, enhancement homogeneous, hilum absent, and perfusion defect were involved in the meta-analysis as the standard of contrast-enhanced ultrasound, among which, perfusion type showed the best diagnostic performance. The pooled estimated sensitivity, specificity, positive likelihood, negative likelihood ratio, and diagnostic odds ratio of perfusion type in contrast-enhanced ultrasound for detecting lymph node metastasis were 0.95 (0.91, 0.97), 0.87 (0.69, 0.96), 7.51 (2.80, 20.14), 0.06 (0.03, 0.10), and 124.17 (42.78, 360.46), respectively. Heterogeneity was moderate. Conclusion The perfusion type in contrast-enhanced ultrasound has good diagnostic performance for cervical lymph nodes metastasis in papillary thyroid carcinoma patients.

Myod and Myf5 are muscle-specific basic helix-loop-helix (bHLH) transcription factors that play essential roles in regulating skeletal muscle development and growth. In order to investigate potential function of myod and myf5 of Megalobrama amblycephala, an economically important freshwater fish species, in the present study, we characterized the sequences and expression profiles of M. amblycephala myod and myf5. The open reading frame (ORF) sequences of myod and myf5 encoded 275 and 240 amino acids, respectively, possessing analogous structure with the highly conserved domains, bHLH and C-terminal helix III domains. Spatio-temporal expression patterns revealed that myod and myf5 were predominant in skeletal muscle with the highest expression in white muscle, and the highest at 10 days post-hatching (dph) and the segmentation period, respectively. Furthermore, we evaluated the effects of lipopolysaccharide (LPS) on the expression of muscle-related genes in white and red muscle, and proliferation and differentiation of satellite cells. The myod, myf5 and pax-7 expression generally increased and then decreased with increase of LPS concentration and treatment time in red muscle, while these genes showed inconsistent expression patterns in white muscle. In addition, LPS administration caused the frequency increase of satellite cells in red and white muscle especially at 3 and 7 days after LPS-injection.

It is still a great challenge that designing proper codoping concentrations of rare earth ions for achieving intensest expected emission from the studied phosphor. In this work, the quadratic general rotary unitized design (QGRUD) was introduced into the codoping concentration option of NaLa(MoO4)2: Er3+/Yb3+ phosphor for upconversion (UC) applications, and the optimum doping concentrations of Er3+ and Yb3+ for achieving maximum UC luminescence intensity, which is close to commercial NaYF4:Er3+/Yb3+ phosphor, were obtained. The two-photon process was assigned to the green UC emissions in the optimized NaLa(MoO4)2: Er3+/Yb3+ phosphor. It was also demonstrated that the optimized phosphor presented more stable upconversion emissions than the commercial NaYF4:Er3+/Yb3+ phosphor.

Real-time aerosol extinction retrieved by Micro-pulse LIDAR and concentrations of PM

This experiment was aimed to discuss the protective effect and mechanism of total lignans from Tibetan medicinal Herpetospermum seeds on carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Forty-eight male Sprague-Dawley rats were randomly divided into the blank control group (G1), model group (G2), total lignans high, middle and low dose groups (400,200, and 100 mg•kg⁻¹•d⁻¹)(G3/4/5) and the glycyrrhizin positive control group (25 mg•kg⁻¹•d⁻¹)(G6), n=8 in each group. The rats in blank group received normal feeding; the rats in model group, total lignans low, middle and high dose groups and glycyrrhizic group were subcutaneously in jected with 3 mL•kg⁻¹ olive oilsolution containing 40%CCl4 every two or three days for Eight weeks. During the course, the rats inblank group and model group were orally administered with 2 mL normal saline, and the rats in total lignans groups and the glycyrrhizin positive control group received corresponding doses of drugs by intragastric administration. Eight weeks later, after the the last time modeling, the rats were sacrificed. Then the biochemical analysis was used to determine alanine aminotransferase(ALT), aspartate aminotransferase(AST), and alkaline phosphatase (ALP) levels in serum while enzyme-linked immuno sorbent assay(ELISA) was applied for detecting transforming growth factor β1(TGF-β1), hyaluronic acid(HA), hydroxy-proline(HYP) and superoxide dismutase(SOD) levels in serum. HE and Masson's trichrome stainings were conducted in liver tissues to observe the pathological variations and grades of hepatic fibrosis. The results showed that as compared with the model group, the levels of ALT, AST, ALP, TGF-β1, HA, HYP and SOD in serum of total lignans groups were significantly decreased (P0.05, P0.01); levels of SOD in the liver tissue homogenate were increased(P0.05, P0.01); the pathological damage of the liver tissues were relieved (P0.05, P0.01), and liver fibrosis scores were decreased(P0.05, P0.01). The above experimentsindicated that total lignans from Tibetan medicinal Herpetospermum seeds can effectively reduce carbon tetrachloride-induced hepatic injury of rat liver fibrosis, reduce the degree of liver fibrosis, and its mechanism maybe associated with down-regulating TGF-β1 expression.

Processing chamber is important part of high-frequency electromagnetic, water processor, In order to determine what kind of processing chamber has better effect to the anti-scal, the paper simulates electromagnetic energy distribution in two common processing chambers by using the software Ansoft Maxwell, which is based on the finite element method. One processing chamber is set with coaxial electrodes and the other one is wrapped by spirals, both are composed by high-frequency electromagnetic pulses. According to the simulation data, electromagnetic energy of processing chamber with coaxial electrodes is much bigger than that of spiral wrapped process chamber. Meanwhile, a mini–circulating water system is built and water quality experiments are completed. Analysis results from experimental data illustrate that two kinds of processing chambers under high-frequency pulsed field have anti-scaling effects, but the processing chamber with coaxial electrodes is much better.

For understanding the effect of MDG-1, a water-soluble β-D-fructan polysaccharide from Ophiopogon japonicas, on intestinal microecological balance, especially on the changes of lactobacillus, sixty 8-week-old male C57BL/6J mice were given a high-fat diet for six weeks and were also gavaged with saline once a day simultaneously. Then the mice which is below 30 grams or dropped more than 10% through lavage were eliminated and the rest were randomly divided into four groups: diet-induced obese (DIO) model group (n = 12, gavaged with saline), low-dose MDG-1 group (n = 12, gavaged with MDG-1, 75 mg · kg(-1)) , medial-dose MDG- 1 group (n = 12, gavaged with 150 mg · kg(-1)), and high-dose MDG-1 group (n = 12, gavaged with 300 mg · kg(-1)) according to the weight and blood glucose; the model group and MDG-1 group were placed on a high-fat diet while the normal control group (n = 12, gavaged with saline) were kept on a low-fat diet through the experiment. After 12-weeks of treatment, feces samples were collected and cultured for intestinal microecological balance analysis. Then the intestinal probiotics were cultured through traditional methods combined with modified gradient gel electrophoresis (DGGE) method. The changes of lactobacillus in each treatment group were also detected by a statistical analysis of the total number of the intestinal flora. We have established the phylogenetic tree by 16S rDNA sequencing and use some molecular identification methods such as PCR-DGGE to analyse the changes of the dominant bacteria floras, and also get the pure culture. In conclusion, different concentrations of MDG-1 can increase the number of the intestinal probiotics, especially Taiwan lactobacillus and Lactobacillus murinus, and improve their diversity and promote proliferation in a dose-dependent way.

Three-factor orthogonal design (OD) of Er3+/Gd3+/T (calcination temperature) is used to optimize the luminescent intensity of NaY(Gd)(MoO4)2:Er3+ phosphor. Firstly, the uniform design (UD) is introduced to explore the doping concentration range of Er3+/Gd3+. Then OD and range analysis are performed based on the results of UD to obtain the primary and secondary sequence and the best combination of Er3+, Gd3+, and T within the experimental range. The optimum sample is prepared by the high temperature solid state method. Photoluminescence excitation and emission spectra of the optimum sample are detected. The intense green emissions (530 nm and 550 nm) are observed which originate from Er3+ 2H11/2→ 4I15/2 and 4S3/2→4I15/2, respectively. Thermal effect is investigated in the optimum NaY(Gd3+)(MoO4)2:Er3+ phosphors, and the green emission intensity decreases as temperature increases.

To observe the therapeutic effect of blood-letting puncture combined with red-hot needle therapy on knee osteoarthritis.One hundred and twenty-nine cases were randomly divided into a bloodletting puncture plus red-hot needle therapy group (n=73) and a routine acupuncture group (n=56). The blood letting puncture plus red-hot needle therapy group were treated by blood-letting puncture at Weizhong (BL 40), and red-hot needle pricking Heding (EX-LE 2), Dubi (ST 35), Xiyan (EX-LE 5), Yinlingquan (SP 9), Yanglingquan (GB 34), Xuanzhong (GB 39) and Ashi points, twice each week, 4 times constituting one course. The routine acupuncture group were treated by routine acupuncture at the same points as those for red-hot needle pricking, once each day, two weeks constituting one course.After treatment for 2 courses, the joint pain score and the illness serious index were 2.68+/-0.88 and 4.25+/-1.02, and 4.68+/-1.89 and 7.46+/-2. 13 in the two groups, respectively, with very significant differences before and after treatment in the two groups (P0.01), the former being better than the later (P0.05). The clinical cured rate and the total effective rate were 37.0% and 94.5% in the blood-letting puncture plus red-hot needle therapy group and 19.6% and 89.3% in the routine acupuncture group, with a very significant difference between the two groups(P0. 01).Blood-letting puncture combined with red-hot needle therapy has obvious therapeutic effect on knee osteoarthritis.