Thoughts on Pairing Assistance to Tibet for Promoting Agricultural High-quality Development in Southern Tibet from the Perspective of Agricultural Power

In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries.

Nutrient status of Populus euphratica growing in desert riparian forests of northwestern China

Seasonal and microhabitat variations of chemical constituents of foliar organic carbon （C）, total nitrogen （N）, total phosphorus （P）, and total potassium （K）, in Populus euphratica growing in desert riparian forests in northwestern China and their correlations were studied. Results show that ranges of C, N, P and K contents in the leaves ofP. euphratica were 39.08%-46.16%, 0.28%-2.81%, 0.05%-0.18% and 0.35%-2.03%, with means of 43.51%, 1.49%, 0.102% and 1.17%, respectively. The ratio of C/N, C/P and N/P changed from 16.26 to 146.61, from 258.08 to 908.67 and from 2.89 to 26.67; the mean was 37.24, 466.27 and 15.14, respectively. The mean N content was significantly lower than of deciduous trees in China, but the mean P content was nearly equivalent. The ratio of C/N was remarkably higher than of global land plants. The ratio of N/P indicated that growth ofP. euphratica was jointly limited by N and P nutrient deficiency. During the growth season, total trends of leaf C, N, P and K contents decreased. The max- imum appeared in May, and the minimum in September. Among microhabitats, C, N and K contents gradually increased from ri- parian lowland, flatland, sandpile, Gobi and dune, but C/N ratio was opposite, and P content was not apparent. Foliar C content was extremely, significantly and positively correlated with N and K contents, respectively. The relationships of N-K and P-K were both significantly positive.

青海湖流域蒸散发对土壤水分的时空响应特征

研究蒸散发对土壤水分的时空响应特征有助于深入理解区域水文循环过程。利用2016—2020年青海湖流域蒸散量和土壤含水量遥感数据,借助ArcGIS空间分析和数理统计方法研究了青海湖流域蒸散发和土壤水分在8 d、月和年尺度的变化特点及两者的对应关系,揭示了青海湖流域蒸散发对土壤水分的时空响应特征。结果显示:(1)2016—2020年,青海湖流域平均蒸散量和土壤含水量分别为494.45 mm和0.34 m^(3)·m^(-3),8 d、月和年尺度蒸散量总体呈先增大后减小的特点,土壤含水量分别呈增大—减小—增大—减小、增大—平稳—减小和较稳定的特点。(2)空间上,各时间尺度青海湖流域平均蒸散量总体呈流域东北向西南方向减小的特点,平均土壤含水量总体由湖滨向流域四周递增、由河谷向两侧递增。(3)时间协同性上,青海湖流域蒸散量和土壤含水量在第1~185天(1—6月)和第241~365天(9—12月)强于第185~241天(7—8月),非生长季强于生长季,2016—2018年强于2018—2020年;空间协同性上,流域东北部的沙柳河和哈尔盖河流域及湖东岸强于其他地区。(4)8 d、月、非生长季和生长季尺度,青海湖流域蒸散量与土壤含水量的平均相关系数分别为0.61、0.69、0.36和0.24,两者以显著正相关关系为主,说明青海湖流域蒸散量对土壤含水量的时间响应在月尺度和8 d尺度较强,不同时间阶段流域蒸散量均随土壤含水量的增加而增大。本研究结果可为深入认识青海湖流域水文循环过程、水量平衡及水资源管理提供理论参考。

单细胞转录组和单细胞染色质开放性图谱解析小鼠γδT细胞异质性

γδT细胞具有重要的免疫监视功能,其不同亚群在维持组织稳态和局部免疫反应中发挥不同作用,但是γδT细胞的异质性尚未完全解析.本文对小鼠胸腺、脾脏和淋巴结中的γδT细胞开展了单细胞转录和染色质开放性组学分析,系统地解析了其异质性.经典的γδT1(IFN-γ^(+))和γδT17(IL-17A;)亚群内部也存在显著的异质性,作者推断了其潜在调控机制.通过对胸腺γδT细胞进行拟时序分析,作者构建了其发育轨迹.有意思的是,作者发现胸腺中存在一群独立于γδT1和γδT17的新亚群—GZMA;γδT细胞,并且发现该亚群具有前体细胞特征.作者还通过转录子活性分析、转录因子识别基序富集发现了一个新的γδT17转录抑制因子—NR1D1,并利用基因敲除小鼠进行了验证.综上,本文构建了小鼠γδT单细胞转录图谱和单细胞染色质开放性图谱,为深入解析γδT细胞异质性和亚群调控机制提供了宝贵的资源库.

Normalization cancer immunotherapy: blocking Siglec-15!

In a recent paper published in Nature medicine,Wang,J.,et al.identified Siglec-15 as a new candidate responsible for adaptive immune resistance and a potential target for normalization cancer immunotherapy.1 Cancer cells can develop various mechanisms to evade tumor-specific and non-specific attacks in the TME of solid tumors.2 Thus,systemic activation of immune systems or even increasing tumor-specific T cells in the peripheral does not necessarily lead to tumor regression.In fact,almost all the known strategies adopted by cancer for immune escape are also used for maintaining systemic homeostasis.

CFTR is a negative regulator ofγδT cell IFN-γproduction and antitumor immunity

CFTR,a chloride channel and ion channel regulator studied mostly in epithelial cells,has been reported to participate in immune regulation and likely affect the risk of cancer development.However,little is known about the effects of CFTR on the differentiation and function ofγδT cells.In this study,we observed that CFTR was functionally expressed on the cell surface ofγδT cells.Genetic deletion and pharmacological inhibition of CFTR both increased IFN-γrelease by peripheralγδT cells and potentiated the cytolytic activity of these cells against tumor cells both in vitro and in vivo.Interestingly,the molecular mechanisms underlying the regulation ofγδT cell IFN-γproduction by CFTR were either TCR dependent or related to Ca^(2+)influx.CFTR was recruited to TCR immunological synapses and attenuated Lck-P38 MAPK-c-Jun signaling.In addition,CFTR was found to modulate TCR-induced Ca^(2+)influx and membrane potential(Vm)-induced Ca^(2+)influx and subsequently regulate the calcineurin-NFATc1 signaling pathway inγδT cells.Thus,CFTR serves as a negative regulator of IFN-γproduction inγδT cells and the function of these cells in antitumor immunity.Our investigation suggests that modification of the CFTR activity ofγδT cells may be a potential immunotherapeutic strategy for cancer.

Metabolic Control ofγδT Cell Function

Metabolic change is associated with cell activities,such as signal transduction,cell differentiation,and cell cycle.In the pathogenesis of autoimmune diseases,abnormal activation of T cells is often accompanied by changes in their metabolism.Conversely,the changes of metabolites can also regulate the proliferation,differentiation,and function of T cells.As a bridge between innate and adaptive immune responses,γδT cells have unique biological characteristics and functions.However,the immunometabolic mechanism ofγδT cells has been a novel field for research in recent years.In this review,we summarize the influence of metabolic pathways and nutrients onγδT cell function,and metabolic features ofγδT cell subsets,which may provide new insights in interventions targetingγδT cells in disease control.

Inhibition of MALT1 paracaspase activity improves lesion recovery following spinal cord injury

Spinal cord injury(SCI) is a devastating traumatic injury that causes persistent, severe motor and sensory dysfunction. Immune responses are involved in functional recovery after SCI. Mucosa-associated lymphoid tissue lymphoma translocation 1(MALT1) has been shown to regulate the survival and differentiation of immune cells and to play a critical role in many diseases, but its function in lesion recovery after SCI remains unclear. In this paper, we generated KI(knock in) mice with a point mutation(C472 G) in the active center of MALT1 and found that the KI mice exhibited improved functional recovery after SCI.Fewer macrophages were recruited to the injury site in KI mice and these macrophages differentiated into anti-inflammatory macrophages. Moreover, macrophages from KI mice exhibited reduced phosphorylation of p65, which in turn resulted in decreased SOCS3 expression and increased pSTAT6 levels.Similar results were obtained upon inhibition of MALT1 paracaspase with the small molecule inhibitor‘‘MI-2' or the more specific inhibitor ‘‘MLT-827'. In patients with SCI, peripheral blood mononuclear cells(PBMC) displayed increased MALT1 paracaspase. Human macrophages showed reduced proinflammatory and increased anti-inflammatory characteristics following the inhibition of MALT1 paracaspase. These findings suggest that inhibition of MALT1 paracaspase activity in the clinic may improve lesion recovery in subjects with SCI.