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Objective To report on the pathological characteristics of brain tissue in a case of Parkinson's disease (PD) with cerebral small vessel disease (CSVD). Methods and Results The male patient, 69 years old, was suddenly died. His brain tissue was donated and accepted by the Human Brain Tissue Bank of China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, 9.50 h after sudden death. The patient was diagnosed with PD, and had undergone deep brain stimulation (DBS), but there was no clinical diagnosis of CSVD. We processed the brain tissue according to standardized procedure of international brain banks. Gross observation showed there was significant discoloration in the substantia nigra and locus coeruleus. The DBS pathway was also visible. Microscopic observation showed in addition to advanced stage of PD (Braak stage Ⅴ), pathological changes of DBS could also be seen, as well as CSVD pathological changes such as microvascular smooth muscle cell proliferation, thickening and hardening vessel walls, hyaline degeneration, lumen stenosis, severe perivascular dilatation, white matter microinfarction and microhemorrhage in frontal lobe, temporal lobe, cingulate gyrus, basal ganglia, brainstem and other areas. The final pathological diagnosis was PD (Braak stage Ⅴ) after DBS and CSVD. Conclusions This brain tissue was enrolled into the brain bank for the clinical diagnosis of PD. Pathological examination showed that in addition to the pathological changes of PD and DBS, CSVD was also coexisted. This case suggests that attention should be paid to the multiple comorbidities of neurological diseases of the elderly. doi:10.3969/j.issn.1672⁃6731.2021.04.006

Final electromagnetic stirring (F-EMS) is widely used in the billet and bloom continuous casting process because it effectively improves the as-cast quality. Numerous industrial trials on F-EMS have been conducted; however, the real melt flow and heat transfer characteristics at the crater end remain unclear. In this study, based on a round billet special steel continuous casting process, a coupled three-dimensional numerical model was developed to describe the F-EMS phenomenon. The flow and solidification behavior of the melt in the F-EMS region were obtained by a segmentation calculation model, and the Darcy source term method was employed to suppress the velocity within the mushy region. The effect of stirring current intensity and frequency on the electromagnetic field, melt flow, and heat transfer was investigated numerically. The model was validated using the measured data of magnetic flux density in the stirrer center and the strand surface temperature. According to the simulation results, with every 100 A increase in the current intensity, the maximal magnetic flux density increases by 19.05 mT. The electromagnetic force significantly increases with the increase in current intensity. With the increase in current frequency within 20-40 Hz, the magnetic flux density decreases slightly, whereas the electromagnetic force increases. Moreover, a swirling flow field in the stirrer region is observed under the rotary electromagnetic force, and the tangential velocity of melt increases with the increase in current intensity and frequency. Additionally, the swirling flow enhances the local melt heat transfer at the radial direction of the round strand. As the current intensity and frequency increase, the temperature of the melt in the liquid core decreases, and the center solid fraction at the F-EMS-implemented position increases accordingly.

The mushy zone refers to the region of the solid-liquid system where the temperature is between the liquidus and solidus temperatures. In this zone, the turbulence of the interdendritic flow is reduced by blockage of dendrites. The mushy zone coefficient (Amush) is an important calculating parameter in the continuous casting numerical simulation process, which strongly affects the prediction of fluid flow and solidification behavior in the mold zone. However, most researchers have neglected the influence of the mushy zone coefficient, and the correct expression of this coefficient is rarely found in the literature. Generally, the lower default value of 1×105 kg·m-3·s-1 is used in the model, which leads to unrealistic results. In this study, the relationship between the mushy zone coefficient and permeability was analyzed, and the expression of the mushy zone coefficient was proposed. A coupled flow and solidification numerical model was developed to evaluate the effect of the mushy zone coefficient on the melt flow and solidification phenomena in a bloom continuous casting mold. Results show that the higher the value of the mushy zone coefficient, the stronger the damping becomes, and the faster the velocity drops as melt solidifies. A relatively high value of the mushy zone coefficient generates a "banded" form of mushy zone sandwiched between the solid and liquid phases in the mold zone. When the mushy zone coefficient is at a lower value, a wider mushy zone is obtained and the melt cools down rapidly in the mold region. In addition, the temperature at free surface is relatively low with supercooling, and the solidified shell remelts locally. The model is validated through comparison with measurements of shell thickness on a breakout shell. The value of the mushy zone coefficient ranging from 1×108 to 5×108 kg·m-3·s-1 is suggested.

The present study is the first to investigate resistance levels ofTetranychus cinnabarinus(Boiduval) in mulberry in southwest China. The toxicity and resistance of seven common acaricides, including dichlorvos, phoxim, methomyl, pyridaben, propargite, abamectin and chlorfenapyr, were assayed for seven mulberry field strains of mites along with a laboratory susceptible strain (SS). The results indicated that most field strains exhibited low to moderate levels of resistance. Mengzi and Xiangyun had moderate resistance to phoxim (RR = 31.45 and 26.22, respectively). The Qiaojia, Luliang, Mengzi and Heqing strains showed moderate resistance to chlorfenapyr (RR = 14.98–22.52). Correlation analysis of resistance ratio in seven acaricides indicated that methomyl and abamectin were negatively correlated. The results provide information for acaricide rotations and resistance management of spider mite in mulberry plantations. [ABSTRACT FROM PUBLISHER]

A three-dimensional numerical model combining electromagnetic field, fluid flow, heat transfer, and solidification has been established to study the effect of nozzle injection mode and mold electromagnetic stirring (M-EMS) on the internal quality of a continuously cast bloom. The model is validated by measured data of the magnetic flux density along the stirrer center line. According to the simulation and experimental results, M-EMS can introduce a horizontal swirling flow ahead of the solidification front, promoting the superheat dissipation of molten steel and columnar to equiaxed transition (CET). As the stirring current increases from 0 to 800 A, the superheat at the mold exit in the bloom center decreases by 1.9 K for the single-port nozzle case and 3.8 K for the five-port nozzle case. The resulting increase in the equiaxed crystal ratio is about 5.65% and 4.06%, respectively. In comparison, the injection mode shows a more significant influence on the heat transfer and solidification structure in the bloom under the present casting conditions. The superheat at the mold exit in the bloom center decreases by 5.1–7.7 K as the injection mode changes from a single-port nozzle to a five-port nozzle, and the increase in the equiaxed crystal ratio ranges between 14.8% and 17%. It is found that the flow velocity of the molten steel in front of the solidification interface for the five-port nozzle is higher than that for the single-port nozzle regardless of the M-EMS power. The washing effect here reinforces both the heat exchange through the solidification interface and the dendrite re-melting or fragmenting, stimulating the formation of an equiaxed crystal at the bloom center. In addition, it is observed that both the central shrinkage and carbon segregation have decreased with the five-port nozzle plus M-EMS. This suggests that the combined application of a five-port nozzle and M-EMS can effectively improve the internal quality of large bloom castings. [ABSTRACT FROM AUTHOR]

High salinity wastewater is one of the difficulties in the field of wastewater treatment. As a new desalination technology, electrosorption technology has many advantages. This paper studied a new type of carbon-based electrodes, the graphite and activated carbon fiber composite electrodes. And the influencing factors of electrosorption and its desalination effect were investigated. The electrosorption device had optimal desalination effect when the voltage was 1. 6 V, the retention time was 60 min and the plate spacing was 1 cm. The graphite and activated carbon fiber composite electrodes were used to treat the black liquor of refined cotton and sodium copper chlorophyll wastewater to investigate its desalination effect. When the electrodes were used to treat the black liquor of refined cotton after acid treatment, the removal rate of conductivity and COD reached 58. 8% and 75. 6% respectively when 8 pairs of electrodes were used. And when the electrode was used to treat the sodium copper chlorophyll wastewater, the removal rate of conductivity and COD reached higher than 50. 0% and 13. 5% respectively when 6-8 pairs of electrodes were used.

Objective: To find a new method of treating hepatocellular carcinoma with melittin by way of using the melittin gene., Methods: The recombinant adenoviruses carrying the melittin gene and alpha-fetoprotein (AFP) promoter (Ad-rAFP-Mel) were constructed through a bacterial homologous recombinant system. The efficiency of the adenovirus mediated gene transfer and the inhibition effect of Ad-rAFP-Mel on the proliferation of hepatocarcinoma cells were determined by X-gal staining and MTT assay respectively. The tumorigenicity of hepatocarcinoma cells transfected by Ad-rAFP-Mel and the antitumor effect of Ad-rAFP-Mel on the transplanted tumors in nude mice were detected in vivo., Results: The mRNA of the melittin gene was transcripted in HepG2 hepatocellular carcinoma cells transducted by Ad-rAFP-Mel. The efficiency of adenovirus mediated gene transfered to BEL-7402 hepatocarcinoma cells was 100% when the multiplicities of infection (MOI) of Ad-rAFP-Mel was 10 in vitro and was high in vivo as well. The inhibitive rates of Ad-rAFP-Mel and Ad-rAFP for BEL7402 cells were 66.2%+/-2.7% and 2.9%+/-2.3% (t = 30.83) by MTT assay. The inhibitive rates of Ad-CMV-Mel for BEL7402, SMMC7721 and L02 cells were 58.9%+/-9.6%, 65.9%+/-3.8%, 31.7%+/-1.2%, respectively, and those of the Ad-rAFP-Mel were 6.2%+/-2.7%, 16.1%+/-6.6%, 7.5%+/-3.3%, respectively (t = 1.27; t = 11.31, and t = 12.12, vs. Ad-CMV-Mel group in same cells). The tumorigenicity rates of hepatocarcinoma cells transfected by Ad-rAFP-Mel were decreased. A significant antineoplastic effect was detectd on transplanted tumor in nude mice by intratumoral injection of Ad-rAFP-Mel., Conclusion: Ad-rAFP-Mel can inhibit specifically the proliferation of AFP-producing human hepatocarcinoma cells in vitro and in vivo. It suggests that animal toxin gene can be used as an interesting antitumor gene.

Objective: To observe the induced apoptosis of recombinant adenovirus carrying melittin gene (Ad-rAFP-Mel) for hepatocellular carcinoma cell line (BEL-7402)., Methods: The morphological observe, DNA electrophoresis, TUNEL and Flow cytometry assay were used to study the apoptosis of BEL-7042 cell line transfected by Ad-rAFP-Mel., Results: The morphological changes and apoptosis of BEL-7402 transfected by Ad-rAFP-Mel were confirmed with microscopy and DNA electrophoresis, TUNEL, Flow cytometry assay. The DNA ladder could be demonstrated on DNA electrophoresis in Ad-rAFP-Mel group. The apoptosis rates of BEL-7402 cells in Ad-rAFP-Mel, Ad-rAFP, and control groups were (21.5+/-2.4)%, (10.5+/-4.4)% and (3.0+/-1.4)% respectively by TUNEL assay (F = 38.0, P < 0.05) and were (7.3+/-0.5)%, (3.9+/-0.1)% and (0.8+/-0.1)% respectively by flow cytometry assay (F = 415.1, P < 0.05)., Conclusion: It seems that melittin inducing apoptosis might be one of the antitumor mechanisms.

Objective: To observe the effects of melittin gene transfection on the biological behavior of hepatocarcinoma cells., Methods: Melittin gene was recombined into a shuttle plasmid under the control by alpha-fetoprotein (AFP) transcription regulatory element (rAFP), and the gene of interest was then recombined into an adenoviral backbone plasmid through a simplified efficient bacterial homologous recombination system. The recombinant adenoviral plasmids were subsequently linearized with Pac I and transfected into 293 cells mediated by lipofectin to generate the desired recombinant adenoviruses. After infections of the hepatocarcinoma cells with the resultant viruses carrying melittin gene was achieved, melittin gene transcription was verified by way of RT-PCR, and CD54 expression was measured by flow cytometry., Results: Recombinant adenoviral vectors containing melittin gene were successfully constructed, and melittin gene transcription was approved by RT-PCR. Flow cytometry results showed that melittin gene transfection inhibited CD54 expression in the hepatocarcinoma cells., Conclusion: Melittin gene transfection may result in changes of the biological behavior of hepatocarcinoma cells, thus decreasing the malignancy of the tumor cells.