[Meta Analysis on Yield Effect of Biochar for Staple Crops in China].

In order to quantitatively evaluate the impact of biochar on the yield of staple crops in China, a total of 866 pairs of data from 116 published studies were collected. Meta analysis was used to quantitatively analyze the impact of biochar on the yield of staple crops in China and its influencing factors. Meanwhile, a structural equation model (SEM) was constructed to further explain the interaction among the factors. The results showed that compared with no biochar application, biochar application could improve the physical and chemical properties of the soil in the main grain fields and increase the yield of the main grain crops, with an average yield increase rate of 8.77%. Among them, when the pH of biochar was 7-8, the average yield increase rate was the highest, reaching 26.49%. When C/N<60, the average yield increase rate was 13.73%, which was significantly higher than that of C/N≥60. Applying biochar to acidic or neutral soil could give full play to its yield-increasing effect. When the amount of carbon applied was 10-20 t·hm-2, the average yield increase rate of wheat and corn was the highest. The average yield of rice was the highest when the amount of carbon was 15-25 t·hm-2. However, the yield-increasing rates of rice with different carbon application levels were similar, so it is possible to consider losing part of the yield and give consideration to the economic benefits by appropriate reduction. In addition, the yield-increasing effect of biochar decreased with the increase in application years, and generally the yield-increasing effect was not significant after three years. The SEM showed that the application amount of biochar not only directly affected the yield of staple crops but also indirectly affected the yield of staple crops by improving soil fertility, whereas biochar C/N and pH only affected the yield of staple crops by improving soil fertility. Therefore, in the future application of biochar, priority should be given to applying it to acidic or neutral soil with low fertility, and its C/N and pH should be controlled below 60 and 7-8, respectively. Soil conditions, biochar characteristics, and field management measures should be comprehensively considered to maximize the yield of staple crops. This research can provide scientific basis and theoretical basis for the popularization and rational application of biochar.

Malignant transformation in a sciatic plexiform neurofibroma in Neurofibromatosis Type 1 - imaging features that aid diagnosis.

A 41-year-old Asian male with NF1 and bilateral sciatic plexiform neurofibromas, presented with unintentional weight loss, increasing size of a left thigh mass associated with increasing pain and radiculopathy. MRI of the left thigh demonstrated imaging features suspicious of malignant transformation. The patient had a new left lung mass, demonstrating avid FDG uptake, raising suspicion for metastasis. Surgical resection of the left thigh mass confirms malignant transformation in a preexisting sciatic plexiform neurofibroma. Diagnosis of malignant transformation in a nerve sheath tumour can be challenging. MRI remains the main preferred imaging modality in the evaluation of these tumours. Imaging features that raise suspicion for malignant transformation are discussed. Although none of these are specific for malignant transformation, studies suggest that the presence of two to four of these features should prompt further investigations.

Construction of anti-cD20scFv/CD80/CD28/zeta recombinant gene modified T cell and research on its targeting cytotoxicity / 中华血液学杂志

<p><b>OBJECTIVE</b>To construct anti-CD20scFv/CD80/CD28/zeta recombinant gene modified T cells, test its effectiveness of eradicating CD20+ lymphoma cells and provide a probably new approach to tumor adoptive immunotherapy.</p><p><b>METHODS</b>CD28-zeta cDNA were amplified from vector pBULLET and inserted into pLNCX vector that contained anti-CD20scFv/CD80 gene. The recombinant vectors were transduced into PA317 cells and high titer retroviruses were obtained to infect human peripheral blood T lymphocytes. Resistant T cells were obtained by G418 selection at one week. Then transduced T lymphocytes and lymphoma cell lines Daudi Raji were cocultured. The cytotoxicity and cytokine production of transduced T cells were determined by non-radio-activation cytotoxicity assay and ELISA respectively.</p><p><b>RESULTS</b>The recombinant eukaryotic vector was constructed successfully as proved by enzyme digestion analysis and sequencing. These T cells were able to lyse CD20+ target cells and secrete high levels of IL-2 and IFN-gamma in vitro.</p><p><b>CONCLUSION</b>Recombinant gene modified T cells can be constructed successfully. It can specially kill CD20 positive lymphoma cells in vitro.</p>

Progress on Swimming Mechanism of Flagellar Bacteria / 微生物学通报

Some types of bacteria swim through rotating their flagella. The swimming mechanism of bacteria during flagella bundling and tumble process is analyzed. The effects of body rotation and flagellum′s polymorphic transitions on bundling processes and the wall effect phenomenon are also discussed. Finally, based on dynamics similarity, a new microrobot module is put forward to further studying the flagella swimming phenomena. The research would be very helpful for constructing the bionic swimming robots under the low Reynolds number.