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For all Eichler orders with a same squarefree level in a definite quaternion algebra over the field of rational numbers, we prove that a weighted sum of Jacobi theta series associated to these orders is a Jacobi Eisenstein series. Multiply the Fourier coefficients of the latter by a power of 2 to get our modified Hurwitz class numbers. As its corollaries, the modified Hurwitz class numbers can be used to calculate the traces of Brandt matrices and the type number of the Eichler orders.

Ethylene glycol and ferric chloride pretreatment assisted by low-pressure carbon dioxide (1 MPa CO

A systematic scale-up study on a rotating packed bed (RPB) reactor is essential before the industrial application. However, the mass transfer and application performance of the RPB reactor with a s...

Liquid dispersion by impacting on wire mesh benefits many mass transfer processes. However, most of studies focused on the dispersion behaviors of liquid impacting on a one-layer wire mesh. In this...

A novel disk-distributor rotating packed bed (DRPB) was developed in this study to promote the application of RPBs for high-viscosity processes. A rotating disk was used as a liquid distributor in the inner cavity of the DRPB to distribute a high-viscosity liquid, and the porous packing was anchored radially outside the disk to additionally disperse the incoming liquid. Three-dimensional Eulerian multiphase simulations were implemented to examine the liquid flow characteristics in the packing after experimental validation. With increasing viscosity (μ) from 11 mPa·s to 59372 mPa·s, flow patterns were transformed from dispersive into continuous modes. Liquid holdup, which ranged from 0.0006 to 0.25, was proportional to μ0.61. Wetting efficiency and wetting height varied in ranges of 0.0012–0.416 and 3.03–14.57 mm, respectively. At a viscosity of 3331 mPa·s, approaches involving the use of multistage DRPB and the installation of redistribution blades improved the axial utilization efficiency of the packing from 20% to 80% and 20% to 92%, respectively.

Mesh packing in rotating packed bed reactors has been intensively exploited. As a crucial parameter of mesh, fiber cross-sectional shape was expected to affect the liquid flow behavior inside packing. Herein, liquid jet impacting on rotating single-layer meshes with various fiber cross-sectional shapes, including circular, elliptical, and quadrangular, were investigated. Liquid flow pattern and dispersion characteristics were studied by visualization. Details of liquid impact-disintegration process and internal velocity and pressure fields were presented via simulation. The curved surface allowed liquid to flow around fiber and converge again, then generated liquid ligaments and films perpendicular to the rotational axis. The sharp edges of quadrangular fiber hampered separated liquid to converge, thus generating liquid films parallel to the rotational axis. The mesh composed of vertical quadrangular fiber and horizontal elliptical fiber reduced average droplet diameter by 16% and liquid maldistribution index by 14% compared to mesh with circular fibers, intensifying liquid dispersion.

The impaction process of droplet on fiber (used as packing) including capture and dispersion is widely encountered in the multiphase reactors. Numerous studies have been conducted to illustrate the captured phenomena, while the phenomena and mechanism of dispersion are still unclear. In this work, the high-speed photography and computational fluid dynamics simulation were employed to investigate the dispersion phenomena of liquid droplet impacting on the single fiber with different wettabilities. Three flow patterns, named one-drop, one-film, and two-film dripping were observed from experimental results. Four contact angle models were implemented in the simulation. The gas–liquid interfacial area and energy utilization efficiency respectively increased from 1.85 to 3.38 times of initial area and from 1.97 % to 48.29 % when the contact angle increased from 45° to 155°. The results are of great significance to understand the dispersion phenomena as well as the enhanced dispersion efficiency of liquid in chemical reactors.

The devolatilization of volatile organic compounds (VOCs) from the viscous liquid like polymers was necessary but of great challenge caused by the high viscosity. In this work, different packing structures were manufactured in a rotating packed bed (RPB), including the stainless steel wire mesh packing (SMP), 3D-printed column packing (PCP), 3D-printed mesh packing with circular fibers (PMP-C), and 3D-printed mesh packing with drop-shaped fibers (PMP-D). The devolatilization performance of the RPB was investigated with the acetone-silicon oil working system. Results indicated that modifying the fiber shape of packing effectively intensified the devolatilization in the RPB. The removal efficiency (η) and volumetric mass transfer coefficient (KLa) of the PMP-D were dramatically larger than the other three packings. Compared the PMP-D with the traditional SMP, the maximum η was enhanced from 40% to 50%, and the increment of KLa was 50% on average. The correlations to predict KLa were established, and the deviations from the experimental results were less than ± 20%.

The oxygen vacancies in CeO2-based catalysts play a vital role in the oxidation reactions due to the repeatable Ce4+/Ce3+ redox cycles. However, the influence of micro-mixing efficiency during co-precipitation reaction on the oxygen vacancy concentration in CeO2-based catalysts was scarce. In this work, a rotating packed bed (RPB) reactor was employed to intensify the micro-mixing of reactants before crystal nucleation, aiming to increase the oxygen vacancy concentration of CeO2-based catalysts. The MOx-CeO2 (M = Cu, Co, Fe) catalysts prepared in the RPB reactor featured more M-O-Ce species and 1.3 – 1.4 times concentration of oxygen vacancy compared to those prepared in a stirred tank reactor (STR). The RPB-CuO-CeO2 catalyst showed an elevated reaction rate of CO (6.70 × 10-4 mol gcat-1 s-1) at 90 °C and remained unchanged after 8 cycles in CO oxidation. This work demonstrates a feasible “nonchemical” strategy to prepare the high-activity solid solution catalysts with increased oxygen vacancies.

With the interactive and accumulative effects of multiple pressures, the dissolved inorganic nitrogen concentration (CDIN) is increasing considerably and is regarded as the dominant chemical pollutant in Jiaozhou Bay (JZB). To efficiently prevent water quality (WQ) deterioration, the relationships among the CDIN in JZB with anthropogenic pressure indicators (APIs) and coastal carrying indicators (CCIs) were identified using long-term series data (1962–2012). First, the control indicators (CIs) were obtained by the application of a conceptual model analysis, and potential sources were identified by a factor analysis. Second, the key CIs were identified by a regression analysis. Finally, the effects of the key CIs on WQ were quantitatively assessed by numerical model experiments. The results showed that the CIs for the CDIN variation contained both APIs, including terrigenous total nitrogen flux (FTN) discharged into JZB, river runoff, sea area of reclamation, and the CCIs, including the water area of JZB (SJZB), chlorophyll-a, dissolved oxygen, pH, salinity and seawater temperature. The APIs on WQ variation were greater than the CCIs. The FTN and SJZB were identified as the key CIs responsible for the variation in the CDIN. The WQ simulation results showed that the increasing trend of the CDIN was caused by the increase in the FTN and the decrease in the SJZB, and the combined effects induced by the two key CIs on the CDIN variation was as high as 79%, higher their separate effects, indicating a synergistic interaction of the two key CIs on the WQ of JZB during the last 50 years. These results illustrated that both terrigenous nitrogen pollutant load control systems and a scientific plan for coastline utilization should be implemented to effectively improve the WQ of JZB.

Myasthenia gravis (MG) is an autoimmune neuromuscular disease characterized by fatigue and muscle weakness. Ginseng is used in the treatment of MG. Ginsenoside Rb1 (G-Rb1), the most abundant ginsenoside in ginseng root, has been proved to be immune regulatory in various diseases. In this study, we investigated the effects and mechanisms of G-Rb1 in treatment for MG in a rat model. Our data showed that G-Rb1 treatment markedly ameliorated the symptoms of experimental autoimmune myasthenia gravis (EAMG) rats, decreased the percentage of Th17 cells in mononuclear cells (MNCs), and increased the number of Treg and Th2 cells in MNCs. We also found that G-Rb1 treatment decreased the serum level of anti-R97-116 peptides IgG1 and IgG2a antibodies. Our findings provide strong evidence that G-Rb1 treatment has immune regulatory effects in EAMG rats, which indicate that G-Rb1 may be employed as a therapeutic medication for MG.

Post-stroke depression (PSD) is one of the most prevalent emotional disorders after stroke and often results in poor outcomes. However, the underlying physiopathologic mechanism and effective treatment of PSD remain poorly elucidated.To investigate whether paeoniflorin has antidepressant-like activity in a rat model of PSD.Rats were randomly divided into four groups: sham-operated control (Sham), PSD, paeoniflorin (with PSD) and fluoxetine group(with PSD). PSD was developed by the right middle cerebral artery occlusion followed 21 days chronic unpredictable mild stress combined (CUMS) with raised alone. Tests of sucrose preference and open field were used to assess the depression-like behavior. Neurological function was evaluated by neurological deficit score and beam balance test. Expression of phosphorylated CREB (p-CREB) and brain-derived neurotrophic factor (BDNF) in the CA1 region of the hippocampal complex was evaluated by western blot and immunofluorescence.Te depressive-like behaviors markedly improved after paeoniflorin and fluoxetine treatment. Furthermore, paeoniflorin treatment significantly increased BDNF and p-CREB expression in the CA1 region.Observed results suggested that paeoniflorin could ameliorate the symptoms and improve the functional capability of PSD rats, similar to the effect of fluoxetine.PSD: post-stroke depression; CUMS: chronic unpredictable mild stress stimulation; MCAO: middle cerebral artery occlusion; OFT: open field test; SPT: sucrose preference test, NDS: neurological deficit score, BBT: beam balance test; BDNF: brain-derived neurotrophic factor protein; p-CREB: phosphorylated Cyclic-AMP responsive element binding protein.

Objective To investigate the effects of Polygoni Cuspidati Rhizoma et Radix (PCRR) and its ingredient resveratrol (Res) on experimental autoimmune myasthenia gravis (EAMG). Methods EAMG was induced in Lewis rats by the immunization of a synthetic peptide corresponding to region 97–116 of the rat acetylcholine receptor (AChR) α subunit (R97-116). EAMG rats were randomly divided into PCRR group, Res group, and control (C) group, and were ig administered respectively with PCRR (2 g/kg), Res (20 mg/kg), and DMSO (0.4 mL/kg) every day from day 5 after immunization to day 42. Clinical evaluation, lymphocyte proliferation, cytokines, and anti-97-116 antibodies were performed for examination of their therapeutic effects. Results Treatments with PCRR and Res significantly ameliorated clinical symptoms, down-regulated TNF-α and up-regulated IL-10 in serum and culture supernatants of lymphocytes stimulated with R97-116, and decreased levels of anti-R97-116 IgG1 and IgG2a in serum compared with C group. Unexpectedly, PCRR but not Res inhibited lymphocyte proliferation compared with C group. Conclusion PCRR and Res ameliorating EAMG is associated with suppressing immune response, and indicates a therapeutic potential for EAMG and even human myasthenia gravis (MG). Res may be the main effective ingredient from PCRR ameliorating EAMG, but further experiments are necessary.

The Rho/Rho kinase (ROCK) pathway serves as molecular switches in many biological processes including the immune response. ROCK inhibitors lead to amelioration of some autoimmune diseases. The present study was designed to define whether a selective ROCK inhibitor, fasudil, was effective in experimental autoimmune myasthenia gravis (EAMG) and investigate the underlying mechanisms. Here we found fasudil effectively attenuated the development of ongoing EAMG. Fasudil abolished the antibody production and function by decreasing follicular helper T cells and CD19(+) B cells, especially germinal center B cells. Moreover, fasudil reduced the expression of CD80 on lymph node mononuclear cells. These findings suggest the inhibition of ROCK might be a potential therapeutic strategy for antibody-mediated autoimmune diseases.

A Gram-stain positive, non-motile, non-sporogenous, aerobic, rod-shaped and halophilic bacterium, designated LAM0015(T), was isolated from a saline sediment sample collected from Yantai City in China. The isolate was found to be able to grow at NaCl concentrations of 5-25 % (w/v) (optimum: 7-12 %), 15-45 °C (optimum: 35 °C) and pH 5.0-9.0 (optimum: 7.0). The major fatty acids were determined to be anteiso-C15:0 and anteiso-C17:0. The predominant respiratory quinone was identified as MK-7. The cell wall peptidoglycan was determined to contain meso-diaminopimelic acid. The polar lipids were found to be diphosphatidyglycerol, phosphatidylglycerol, five phospholipids and one glycolipid. The DNA G+C content was 43.1 mol% as determined by the T m method. Analysis of the 16S rRNA gene sequence indicated that the isolate belongs within the genus Lentibacillus and is closely related to Lentibacillus persicus DSM 22530(T), Lentibacillus salicampi JCM 11462(T) and Lentibacillus jeotgali JCM 15795(T) with 97.3, 96.7 and 96.4 % sequence similarity, respectively. The DNA-DNA hybridization value between LAM0015(T) and L. persicus DSM 22530(T) was 51.2 ± 1.4 %. Based on its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM0015(T) is concluded to represent a novel species of the genus Lentibacillus, for which the name Lentibacillus amyloliquefaciens sp. nov. is proposed. The type strain is LAM0015(T) (=ACCC 06401(T) = JCM 19838(T)).

Liquid-solid mass transfer model is significant but deficient for the design of a rotating trickle-bed reactor (RTBR), which has great potential for process intensification of heterogeneous catalytic reactions. In this work, a mathematical model considering the wetting efficiency was first established to describe the liquid-solid mass transfer process in the RTBR. External static liquid holdup was referred to give a reasonable initial value for calculation. The profile of concentration boundary layer was obtained by mass balance analysis of an Eulerian element on a single sphere. The above model was then extended to predict the liquid-solid mass transfer coefficient (kLS) in the RTBR. A copper dissolution method was employed to measure the kLS, considering the effects of particle diameter, rotational speed, and liquid superficial mass velocity. The comprehensive comparison between predicted and experimental values of kLS was conducted and deviations were within ±25%.

Axon regeneration after cerebral ischemia in mammals is inadequate to restore function, illustrating the need to design better strategies for improving outcomes. Improvement of axon regeneration has been achieved through fastigial nucleus electrostimulation (FNS) in animal researches. However, the mechanisms underlying this neuroprotection remain poorly understood. Increasing the levels of the second messenger cyclic AMP (cAMP) enhances axon regeneration, making it an excellent candidate molecule that has therapeutic potential. In the present study, we examined the expression of cAMP signaling in ischemic brain tissues following focal cerebral ischemia. Adult rats were subjected to ischemia induced by middle cerebral artery occlusion (MCAO). A dipolar electrode was placed into the cerebellum to stimulate the cerebellar fastigial nucleus for 1 h after ischemia. Neurological deficits and the expressions of cAMP, PKA (protein kinase A) and ROCK (Rho-kinase) were determined. Axonal regeneration was measured by upregulation of growth-associated protein 43 (GAP43). The data indicated that FNS significantly enhanced axonal regeneration and motor function recovery after cerebral ischemia. FNS also significantly increased cAMP and PKA levels after ischemic brain injury. All the beneficial effects of FNS were blocked by Rp-cAMP, an antagonist of PKA. Our research suggested that the axonal regeneration conferred by FNS was likely achieved via the regulation of cAMP/PKA pathway.

Artesunate is a semi-synthetic derivative of a Chinese herb named Artemisia annua L. that is commonly used as an antimalarial agent in the history of traditional Chinese medicine. Many studies have reported artesunate possesses anti-inflammatory and immunoregulation properties. The present study was conducted to explore whether artesunate was effective in experimental autoimmune myasthenia gravis (EAMG) in Lewis rats. Our data showed that artesunate could improve the clinical symptoms and suppress the development of EAMG. Artesunate exerted its immunomodulatory effects by inhibiting lymphocyte proliferation and the expression of costimulatory molecules CD86, modulating Th1/Th2 cytokine expression levels, and enhancing the level of Treg cells. The final result of administration of artesunate was the decreased synthesis of anti-R97-116 IgG, IgG2a, and IgG2b antibodies. The treatment effect of artesunate was more obvious at dose of 10 mg/kg. These date suggest that artesunate might be a potential drug for the treatment of human myasthenia gravis (MG).

Many countries in the world have implemented many price support policies to promote the development of renewable energy, and there are evolutionary processes between different policies at different stages of national development. Existing literature has less research on the internal mechanism and alternative process of renewable energy price policies’ evolution process. In view of this, this paper innovatively introduces the classic model of innovation diffusion theory, the Bass model, into the renewable energy price mechanism, and improves it on the basis of the traditional Bass model, and then proposes a system dynamics (SD) simulation based on the improved Bass model to study the evolution process of the renewable energy price policies. This paper mainly studies the evolution process of the policies from feed-in tariff (FIT) to renewable portfolio standard (RPS), and takes China’s wind power industry as an example to simulate the model. The results show that FIT can effectively and quickly evolve to RPS based on the internal influence of the interaction among power generation enterprises and the external influence of government behaviors. All the power generation enterprises will implement RPS, and the amount of green power enterprises eventually grows steadily and slowly. In addition, increasing the decline rate of FIT subsidy and RPS unit fine can effectively promote the evolution of RPS policy, and also improve the amount of green power enterprises and the activity of the tradable green certificates (TGC) trading market.

The implementation of the carbon trading (CT) mechanism is important for the transformation of China’s renewable energy industry, thereby affecting the structure of energy, economy, and the environment, and determining the sustainable development of China’s economic-energy-environment (3E) system in the future. This paper constructs a 3E system simulation model under the CT mechanism based on the theory of system dynamics and taking the Beijing-Tianjin-Hebei region as an example. We study the internal operation mechanism of the carbon emissions trading system and its impact on 3E by combing the related mechanisms of the CT market, CO2 emissions, energy consumption, and gross domestic product (GDP), thereby helping to provide references for policy-making institutions. The results show that the implementation of CT can effectively reduce energy consumption growth and carbon emissions in the Beijing-Tianjin-Hebei region, and the negative impact of CT implementation on GDP is significantly lower than its positive impact on reducing carbon emissions and energy consumption. Thus, the CT mechanism is conducive to the sustainable development of the Beijing-Tianjin-Hebei region’s 3E system. In addition, reducing the total amount of quota, reducing free quota, and increasing CT price can effectively promote carbon emission reduction, thus promoting the sustainable development of the 3E system.