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In the current research, a 60-day experiment was conducted with the purpose of exploring the impacts of methionine on growth performance, muscle nutritive deposition, muscle fibre growth and type I collagen synthesis as well as related signaling pathway. Six diets (iso-nitrogenous) differing in methionine concentrations (2.54, 4.85, 7.43, 10.12, 12.40 and 15.11 g kg-1 diets) were fed to 540 grass carp (178.47 ± 0.36 g). Results showed (P < 0.05) that, compared with methionine deficiency, optimal level of dietary methionine (1) increased feed intake (FI), feed efficiency (FE), specific growth rate (SGR) and percentage weight gain (PWG); (2) increased fish muscle protein, lipid and free amino acid contents, and improved fish muscle fatty acid profile as well as increased protein content in part associated with TORC1/S6K1 signaling pathway; (3) increased the frequency distribution of muscle fibre with >50 µm of diameter; (4) increased type I collagen synthesis partly related to TGF-β1/Smads and CK2/TORC1 signaling pathways. In conclusion, dietary methionine improved muscle growth, which might be due to the regulation of muscle nutritive deposition, and muscle fibre growth and type I collagen synthesis related signal molecules. Finally, according to PWG and muscle collagen content, the methionine requirements for on-growing grass carp (178-626 g) were estimated to be 9.56 g kg-1 diet (33.26 g kg-1 protein of diet) and 9.28 g kg-1 diet (32.29 g kg-1 of dietary protein), respectively.
A new fast-growing mycobacterium, designated strain QGD101T, was isolated from the sputum of an 84-year-old man suspected of tuberculosis in Wuhan Medical Treatment Center, Hubei, China. This strain was a gram-staining-negative, aerobic, non-spore-forming and catalase-positive bacterium, which was further identified as the NTM by PNB and TCH tests. The moxifloxacin and levofloxacin exhibited strong suppressing function against QGD101T with MIC values of 0.06 and 0.125 µg/ml after drug susceptibility testing of six main antimicrobial agents on mycobacteria. Based on the sequence analysis of 16S rRNA, rpoB, hsp65 and 16S-23S rRNA internal transcribed spacer, the strain QGD101T could not be identified to a species level. Mycobacterium moriokaense ATCC43059T that shared the highest 16S rRNA gene sequence similarity (98%) with strain QGD101T was actually different in genomes average nucleotide identity (78.74%). In addition, the major cellular fatty acids of QGD101T were determined as C18:1ω9c, C16:0 and C18:2ω6c. The DNA G + C content was 64.9% measured by high performance liquid chromatography. Therefore, the phenotypic and genotypic characterisation of this strain led us to the conclusion that it represents a novel species of mycobacteria, for which the name Mycobacterium hubeiense sp. nov. (type strain QGD101T = CCTCCAA 2017003T = KCTC39927T) was proposed. Thus, the results of this study are very significant for the clinical diagnosis of tuberculosis and future personalised medicine.
Swelling deformation tests of Kunigel bentonite and its sand mixtures were performed in distilled water and NaCl solution. The salinity of NaCl solution has a significant impact on the swelling properties of bentonite, but not on its surface structure. The surface structure was characterized using the fractal dimension Ds. Based on the fractal dimension, a unique curve of the em–pe relationship (em is the void ratio of montmorillonite and pe is the effective stress) at full saturation was introduced to express the swelling deformation of bentonite–sand mixtures. In mixtures with a large bentonite content, the swelling deformation always followed the em–pe relationship. In mixtures with a small bentonite content, when the effective stress reached a threshold, the void ratio of montmorillonite em deviated from the unique em–pe curve due to the appearance of a sand skeleton. The threshold of vertical pressure for mixtures in different solutions and the maximum swelling strains were estimated using the em–pe relationship. The good agreement between estimates and experimental data suggest that the em–pe relationship might be an alternative method for predicting the swelling deformation of bentonite–sand mixtures in salt solution.
AZ91 magnesium plates with a thickness of 6 mm were subjected to one- and two-pass friction stir processing (FSP). Microstructures and mechanical properties of the experimental materials were investigated. The results show that FSP can significantly refine the microstructures of magnesium alloys, and two-pass FSP can prepare slightly finer grains in comparison with one-pass FSP. Some coarse β-Mg17Al12 phases existed in the first pass FSP break and dissolve into the matrix under the action of the second pass FSP. Microhardness distribution of the two-pass FSP AZ91 alloy exhibits no too much difference with that of the one-pass FSP AZ91 alloy. Due to further finer microstructures, the tensile properties of the two-pass FSP alloy are slightly higher than those of the one-pass FSP alloy. Both FSP AZ91 alloys show typical ductile fracture characteristics, while the dimples on the two-pass FSP specimen are much deeper and increase in quantity.
Actinocerid nautiloids from the Lhasai Formation in the Xainza region are studied systematically for the first time. The nautiloids are identified as Middle Ordovician in age based on stratigraphic correlations with those from North China, Sibumasu, North Australia (northern Gondwana), and North America (Laurentia). A cluster analysis shows strong affinities between the actinocerid nautiloids of the Lhasa Terrane and those of the Himalaya, North China, and Sibumasu terranes. Our results support Middle Ordovician paleogeographic reconstructions that place North China rather than South China much closer to Australia. Nine species assigned to six genera of Meitanoceratidae, Wutinoceratidae, Armenoceratidae, Ormoceratidae, and Discoactinoceratidae are described in detail: Pomphoceras nyalamense (Chen, 1975), Pomphoceras yaliense (Chen, 1975), Wutinoceras cf. W. foerstei (Endo, 1930), Mesowutinoceras giganteum Chen in Chen and Zou, 1984, Armenoceras tani (Grabau, 1922), Armenoceras teicherti Endo, 1932, Armenoceras xizangense new species, Deiroceras globosom Zou and Shen in Chen and Zou, 1984, and Discoactinoceras cf. D. multiplexum Kobayashi, 1927.
Poly(lactic acid) (PLA)/graphene oxide (GO) nanocomposites were prepared by solution mixing. Differential scanning calorimetry results indicated that GO was an effective nucleating agent. The size of spherulites decreased, the density of spherulites increased with increasing GO and the crystallinity of PLA increased from 4.34 to 49.01%. For isothermal crystallization, the crystallization rates of PLA/GO nanocomposites were significantly higher than that of neat PLA, in which t0.5 reduced from 9.0 to 2.8. Spindle-like nanopores (about 100–200 nm) that arranged like spherulites were prepared by low temperature foaming. It was found that the crystallization rate increase and spherulite morphology change were insignificant when the content of GO exceeded 0.5 wt%, because the excessive GO increased the number of nucleation sites while restricting the PLA crystal growth. Thus, the arrangement of nanopores did not mimick the spherulites because of imperfect crystal morphology.
SG-III laser facility is now the largest laser driver for inertial confinement fusion research in China. The whole laser facility can deliver 180 kJ energy and 60 TW power ultraviolet laser onto target, with power balance better than 10%. We review the laser system and introduce the SG-III laser performance here.
While oral antidepressants reach efficacy after weeks, single-dose intravenous (i.v.) ketamine has rapid, yet time-limited antidepressant effects. We aimed to determine the efficacy and safety of single-dose i.v. ketamine augmentation of escitalopram in major depressive disorder (MDD).
Thirty outpatients with severe MDD (17-item Hamilton Rating Scale for Depression total score ⩾24) were randomized to 4 weeks double-blind treatment with escitalopram 10 mg/day+single-dose i.v. ketamine (0.5 mg/kg over 40 min) or escitalopram 10 mg/day + placebo (0.9% i.v. saline). Depressive symptoms were measured using the Montgomery–Asberg Depression Rating Scale (MADRS) and the Quick Inventory of Depressive Symptomatology – Self-Report (QIDS-SR). Suicidal ideation was evaluated with the QIDS-SR item 12. Adverse psychopathological effects were measured with the Brief Psychiatric Rating Scale (BPRS)-positive symptoms, Young Mania Rating Scale (YMRS) and Clinician Administered Dissociative States Scale (CADSS). Patients were assessed at baseline, 1, 2, 4, 24 and 72 h and 7, 14, 21 and 28 days. Time to response (⩾50% MADRS score reduction) was the primary outcome.
By 4 weeks, more escitalopram + ketamine-treated than escitalopram + placebo-treated patients responded (92.3% v. 57.1%, p = 0.04) and remitted (76.9% v. 14.3%, p = 0.001), with significantly shorter time to response [hazard ratio (HR) 0.04, 95% confidence interval (CI) 0.01–0.22, p < 0.001] and remission (HR 0.11, 95% CI 0.02–0.63, p = 0.01). Compared to escitalopram + placebo, escitalopram + ketamine was associated with significantly lower MADRS scores from 2 h to 2 weeks [(peak = 3 days–2 weeks; effect size (ES) = 1.08–1.18)], QIDS-SR scores from 2 h to 2 weeks (maximum ES = 1.27), and QIDS-SR suicidality from 2 to 72 h (maximum ES = 2.24). Only YMRS scores increased significantly with ketamine augmentation (1 and 2 h), without significant BPRS or CADSS elevation.
Single-dose i.v. ketamine augmentation of escitalopram was safe and effective in severe MDD, holding promise for speeding up early oral antidepressant efficacy.
The work was intended to explore the effect of the widely available cationic polymer polyethylenimine (PEI) on small diameter poly(ɛ-caprolactone) (PCL) blood vessel grafts. PEI was blended with PCL and electrospun into nanofibrous vascular scaffolds. The morphologies, wettabilities, mechanical properties, and biological activities of the PCL/PEI electrospun nanofibers were investigated. It was found that by increasing the content of PEI to 5% within the scaffolds, the fiber diameters decreased from 469.7 ± 212.1 to 282.5 ± 107.1 nm, the water contact angle was reduced from 126.6 ± 1.1° to 27.6 ± 3.9°, while the Young's modulus increased from 2.0 ± 0.2 to 4.1 ± 0.1 MPa, the suture retention strength increased from 4.2 ± 0.4 to 6.1 ± 0.7 N, and the burst pressure increased from 801.2 ± 14.1 to 926.2 ± 22.8 mmHg. The in vitro evaluations demonstrated that the nanofibers containing 2% PEI promoted the attachment and proliferation of human umbilical vein endothelial cells (HUVECs).
The robust spines and sclerites of the early to middle Cambrian ‘mollusc’ Wiwaxia are ubiquitous in suitably preserved deposits, but are strikingly absent from the Chengjiang Lagerstätte (Cambrian Stage 3, Yunnan Province, SW China). Here we provide the first record of Wiwaxia sclerites from this rich deposit, extending the record of the genus to the earliest Cambrian Series 2. This reinforces the cosmopolitan distribution of this iconic Cambrian lophotrochozoan and demonstrates the strong faunal continuity that unites distant Cambrian Lagerstätten.
Microcellular injection molding, a process capable of mass-producing complex plastic parts, and particle leaching methods were combined to fabricate porous thermoplastic polyurethane tissue engineering scaffolds. Water soluble polyvinyl alcohol (PVOH) and sodium chloride (NaCl) were used as porogens to improve the porosity and interconnectivity as well as the hydrophilicity of the scaffolds. It was found in the study that the microcellular injection molding process was effective at producing high pore density and porosity. The addition of PVOH decreased the pore diameter and increased the pore density. Furthermore, scaffolds with NaCl and PVOH porogens showed more interconnected pores. The 3T3 fibroblast cell culture was used to confirm the biocompatibility of the scaffolds. Residual PVOH content after leaching increased the hydrophilicity of the scaffolds and further improved cell adhesion and proliferation. The resulting scaffolds offer an alternative scalable tissue scaffold fabrication method for soft tissue scaffold production.
Meningiomas account for approximately 24-30% of primary intracranial neoplasms. Histopathologic grade and degree of resection are two major prognostic factors. The aim of this study was to determine the factors associated with the prognosis of meningioma.
We used immunohistochemistry to analyze the expression levels of Vav3, SPARC, p-Akt, cyclin D1, and Ki-67 in 287 meningiomas of all grades.
The expression of Vav3, SPARC, p-Akt, cyclin D1, and Ki- 67 significantly increased with meningioma grade (p<0.01), and was higher in brain-invasive meningiomas compared to non-invasive meningiomas (WHO grade I) (p<0.05). Furthermore, the expression of Vav3, p-Akt, and Ki-67 was higher in recurrent meningiomas compared to non-recurrent meningiomas (WHO grade I) (p<0.05).
The expression of Vav3, SPARC, p-Akt, cyclin D1, and Ki-67 in meningiomas appears to correlate with meningioma invasiveness, aggressiveness, and recurrence.
Light propagation in a coupled system of Tamm plasmon-polariton and nonlinear cavity mode is theoretically investigated through the nonlinear transfer matrix method. It is found that the asymmetric layered structure exhibits both pronounced unidirectionality and high transmission. This leads to all-optical diode actions. Compared with other similar studies, the designed structure is much simple only with seven periods. The unique feature is that the direction of on-off can be reversed depending on the working frequencies. The effect of metal loss is also considered in this study.
To isolate and identify antioxidant peptides from enzymatically hydrolysed whey protein, whey protein isolate was hydrolysed by different protease (trypsin, pepsin, alcalase 2·4L, promatex, flavourzyme, protease N). The hydrolysate generated by alcalase 2·4L had the highest antioxidant activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, superoxide radicals and in a linoleic acid peroxidation system induced by Fe2+. The IC50 values of DPPH and superoxide radical scavenging activities of the hydrolysate decreased significantly (6·89 and 38·88%, respectively) after treatment with macroporous adsorption resin. Seven different peptides showing strong antioxidant activities were isolated from the hydrolysate using consecutive chromatographic methods including gel filtration chromatography and high-performance liquid chromatography. The molecular mass and amino acids sequences of the purified peptides were determined using a Quadrupole time-of-flight mass spectrometer (Q-TOF MS). One of the antioxidative peptides, Trp–Tyr–Ser–Leu, displayed the highest DPPH radical scavenging activity (IC50=273·63 μm) and superoxide radical scavenging activity (IC50=558·42 μm). These results suggest that hydrolysates from whey proteins are good potential source of natural antioxidants.
Porous thermoplastic polyurethane (TPU) membranes were produced by the electrospinning process. Two different TPUs and their blends were used to investigate the effects of material composition, solution concentration, and rheological properties on the microstructure, fiber diameter, and fiber diameter distribution of the electrospun membranes. The ratios of hard and soft segments in the solutions were adjusted by varying the blend ratios of TPUs dissolved in N, N-dimethylformamide. The solutions with higher TPU concentrations and more hard segments exhibited a higher viscosity, larger storage and loss moduli, and greater electrospun jet stability. Solutions with concentrations around the critical chain entanglement concentration (Ce) produced bead or beaded fiber structures, while bead-free fibers of a uniform diameter were obtained when the concentration increased to about two times that of Ce. Relationships between the electrospun fiber diameter, the Berry number, and the normalized concentration of the solutions were studied as well.
Ultrashort electron bunch trains can be used for plasma wake field acceleration (PWFA) to overcome the limit of transformer ratio of a single electron bunch, or high-power terahertz (Thz) radiation production by various radiation mechanisms. Basic facility for high-power THz radiation development based on ultrashort electron beam has been set up at accelerator lab of TUB. Using birefringent crystal serials, ultraviolet (UV) pulse shaping for photocathode radio frequency gun to produce THz-repetition-rate pulse train was realized. Driven by such pulses, ultrashort electron bunch train with picosecond (ps) spacing was obtained for THz production. Measurement of the stacked UV pulse trains was done by difference frequency generation (DFG), and the measured group velocity mismatch of α-BBO crystal at 266.7-nm wavelength was 0.8 ps/mm. This method may also be applied to form ramped electron bunch trains for PWFA.
The four new transit light curves of WASP-12b are analyzed by using MCMC simulation so as to derive the system parameters. If the apsidal precession exists in the orbit of WASP-12b, according to the theory of Gimenez & Bastero (1995), the rate of precession is estimated as 0.0076 degrees per cycle in the case of orbit with an inclination of 90°.
Four new transit light curves of XO-2b obtained in 2008 and 2009, are analyzed by using MCMC algorithm, and the system parameters are derived. The result demonstrates that the orbital period of the system obtained from new observations is almost the same as Burke et al.'s one (2007), which does not confirm the result of Fernandez et al. (2009).
Genistein and folic acid have been reported respectively to protect against the development of cognitive dysfunction; however, the underlying mechanism(s) for this protection remain unknown. In this report, the mechanism(s) contributing to the neuroprotective effects of genistein and folic acid were explored using rat cortical neuron cultures. We found that genistein and folic acid, both separately and collaboratively, increased cell viability and mitochondrial membrane potential in β-amyloid (Aβ) 31-35-treated neurons. Furthermore, reduced percentage of comet cells and shortened tail length were observed in the neurons treated with genistein or folic acid. A more significant reduction in tail length of the comet neurons was observed in the co-administered neurons. RT-PCR analysis of the cultured cortical neurons showed down-regulated expression of p53, bax and caspase-3, but up-regulated expression of bcl-2 in the three neuroprotective treatment groups compared with neurons from the Aβ31-35 solo-treated group. In a nuclear dyeing experiment using Hoechst 33342, we found that both genistein and folic acid prevent neuronal apoptosis. Collectively, these findings suggest that the mechanism underlying the neuroprotection of genistein and folic acid singly or in combination observed in cultured cortical neuron studies might be related to their anti-apoptotic properties.
The effect of Li3N additive on the Li-Mg-N-H system was examined with respect to the reversible dehydrogenation performance. Screening study with varying Li3N additions (5, 10, 20, and 30 mol%) demonstrates that all are effective for improving the hydrogen desorption capacity. Optimally, incorporation of 10 mol% Li3N improves the practical capacity from 3.9 wt% to approximately 4.7 wt% hydrogen at 200 °C, which drives the dehydrogenation reaction toward completion. Moreover, the capacity enhancement persists well over 10 de-/rehydrogenation cycles. Systematic x-ray diffraction examinations indicate that Li3N additive transforms into LiNH2 and LiH phases and remains during hydrogen cycling. Combined structure/property investigations suggest that the LiNH2 “seeding” should be responsible for the capacity enhancement, which reduces the kinetic barrier associated with the nucleation of intermediate LiNH2. In addition, the concurrent incorporation of LiH is effective for mitigating the ammonia release.