陆地棉背景的Pima棉染色体片段置换系创制

染色体片段置换系(CSSLs,chromosome segment substitution lines)基因组内只有1个或少数几个纯合的供体亲本染色体片段,而其余部分与受体亲本相同,是进行QTL分析的理想材料。本研究以陆地棉中棉所8号(CCRI8)为受体亲本,海岛棉Piam90-53为供体亲本在BC3F1-3借助分子标记辅助选择培育了一套182个株系构成的染色体片段置换系。这套置换系置换片段平均长度21.0 c M,总长度19957.8 c M,是棉花基因组总长度4168.7 c M的4.7倍。每个株系内置换片段长度不一,最短为0.7 c M,最长是83.2 c M,导入片段数量为1~11个。CSSLs在纤维品质性状上的分布表现为相对连续的正态分布,部分株系较CCRI8有了明显提高。本研究为进一步开展棉花纤维品质QTL定位以及陆地棉纤维品质育种研究提供了新材料。     

2-Deoxyglucose Incorporation in the Cerebellum of Weaver and Nervous Mutant Mice

Abstract: The 2-deoxyglucose autoradiographic method has been used to study activity in cerebellum of the weaver and nervous mutant mice. Patterns of 2-deoxyglucose incorporation into the cerebral hemispheres from weaver and nervous strains did not differ significantly from those of the controls. In the normal cerebellum, 2-deoxyglucose incorporation was maximal in the granular layer, where mossy fibers form synapses with the dendrites of granule cells. In the cerebellum of nervous mice, which lacks Purkinje cells, the incorporation of the 2-deoxyglucose was maximal in the granular layer, but the incorporation into the molecular layer appeared less than in the control. The incorporation into the cerebellum from weaver, which lacks granule cells, was much higher than that of the control, the maximal incorporation being found in the Purkinje cell layer and in cell masses located in the white matter. These data suggest that the heterologous synapses that mossy fibers or climbing fibers form with the cells in the Purkinje cell layer and the cells in the white matter in the weaver cerebellum are functional.     

新型生物医用材料—止血纤维的制备与应用研究

作者以高分子生物医用材料,采用气体牵伸纺丝技术,制备了医用止血纤维。经止血机理及结构的研究,其在外伤止血、护创和手术局部止血方面疗效显著。     

Cotton Biotechnology

Genetically modified (GM) cotton altered for insect and herbicide resistance released into commercial production in 1996 to 1997 now accounts for the lion's share of cotton acreage in the U.S. The rapid increase in transgenic cotton acreage in such a short period of time attests to the overall success of agricultural biotechnology. Grower satisfaction with transgenic cotton is largely due to several significant benefits, such as lower production costs, streamlined yet flexible management, and a reduced impact on the environment. This review article provides an overview of what has been accomplished thus far, as well as what improved germplasm may lurk on the horizon. A critical assessment of the gene delivery systems in cotton and possible targets for improvement is presented. The performance of the first generation of transgenic cotton plants engineered for insect, disease, or herbicide resistance is evaluated from the perspective of the benefits, the limitations that impact field performance, and management strategies. A few traits that hold future promise for increasing fiber productivity, enhancing and/or increasing the novelty of cotton-based products for the consumer, and improving human health and well-being are presented. Above all, cotton biotechnology offers to greatly enhance breeding programs by introducing novel traits that have eluded more traditional plant improvement methods and therefore will likely play an increasingly important role in the genetic improvement of cotton.     

神府东胜煤田弃土弃渣体径流产沙过程的野外试验

采用野外模拟降雨试验方法,研究了神府东胜煤田开采造成的弃土弃渣体产流产沙规律及其减水减沙效益.结果表明： 随降雨强度的增大,弃土弃渣体产流的起始时间呈递减趋势,且差异达几倍至十几倍.弃渣体比弃土体更快到达稳定流速,平均流速大小为弃土体>沙多石少弃渣体>沙少石多弃渣体.弃土弃渣体产流6 min后的径流率达到稳定,与降雨强度呈显著相关.弃土弃渣体侵蚀主要发生在产流开始后的前6 min,弃土体产流后前6 min的平均含沙量是6 min后的0.43～4.27倍,弃渣体为1.43～54.93倍.弃土体和沙多石少弃渣体径流量与降雨强度呈线性函数关系,沙少石多弃渣体呈幂函数关系.弃土体和沙少石多弃渣体的次侵蚀量与降雨强度之间分别呈指数函数和幂函数相关.弃土体侵蚀量与径流量呈线性函数关系.在降雨强度为1.0和1.5 mm·min^-1条件下,弃渣体采用鱼鳞坑及植被防护的产流滞后降雨时间为24 min,减水效益为29.5%～52.9%,减沙效益为85.7%～97.9%.     

采伐剩余物管理对杉木人工林土壤nosZ型反硝化细菌群落多样性的影响

反硝化细菌是土壤氧化亚氮(N₂O)排放的关键因子。以杉木人工林为研究对象,设置4种采伐剩余物处理方式(RF:对照;RB:火烧;MT:粉碎;NR:移除),采用高通量测序技术,以nosZ为标记基因,测定了自2018年9月—2020年9月,2年期间土壤nosZ型反硝化细菌群落的组成和丰度。研究结果显示,4种采伐剩余物处理中的土壤nosZ型反硝化细菌90%以上来自变形菌门,优势菌属包括固氮螺菌属、中慢生根瘤菌属、动胶菌属、伯克霍尔德菌属、嗜酸菌属、慢生根瘤菌属、假单胞菌属、固氮弧菌属以及无色杆菌属;样本间差异物种的显著性分析表明,在处理完成半年时,火烧相较于对照于β-变形菌纲水平显著增加了nosZ基因丰度;在处理完成一年时,火烧分别于红螺菌目、红螺菌科、固氮螺菌属水平显著高于粉碎;粉碎相较于移除在处理完成一年时,于γ-变形菌纲和产碱菌科水平显著增加了nosZ基因丰度;在处理完成两年时,粉碎处理的nosZ基因丰度在变形菌门水平显著高于对照和火烧。α多样性数据显示,处理完成一年时,粉碎处理相较于对照和移除显著增加了Shannon和Simpson指数;处理完成两年时,粉碎和火烧...     

Sensory Neurons Contacting the Cerebrospinal Fluid Require the Reissner Fiber to Detect Spinal Curvature In Vivo

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Muscle fiber type characteristics in females with chronic obstructive pulmonary disease. A preliminary study

Chronic obstructive pulmonary disease (COPD) is known to elicit intrinsic abnormalities in male skeletal muscle. However, it is unclear to what extent these changes occur in women and whether they are fiber-type specific. We investigated fiber-type specific differences in selected histochemical properties in muscle obtained from women with moderate to severe COPD compared to healthy control (CON) women. Tissue was obtained from the vastus lateralis in five COPD patients (age 66.9 ± 2.6 years; FEV₁ = 43 ± 7%) and eight CON (age 68 ± 4.9 years; FEV₁ = 113 ± 4.2%). Compared to CON, the distribution (30.6 ± 5.2 vs. 57.9 ± 4.6%) and cross sectional area of type I (CSA, 5660 ± 329 vs. 3586 ± 257 μm²) and type IIA (2770 ± 302 vs. 2099 ± 206 μm²) were lower (P < 0.05) and higher (P < 0.05), respectively, in COPD. Disease state did not alter either the distribution or CSA of the IIA, IIAX or type X subtypes. Although differences were found between fiber types in the number of capillary contacts (n) (I > IIAX, IIX; IIA > IIX) and the capillaries per CSA (μm²10⁻³) (I < IIA, IIAX, IIX), no differences were found between CON and COPD. Succinic dehydrogenase activity and sarcoplasmic reticulum (SR) Ca²⁺-ATPase activity, measured photometrically (OD units), were higher (P < 0.05), and lower (P < 0.05), respectively, in type I compared to the type II fiber subtypes. These properties were not altered with COPD. COPD in females is accompanied by a higher percent of type II fibers, a larger CSA of type I and type IIA fibers, both of which occur in the absence of differences in oxidative potential and the potential for SR Ca²⁺-sequestration.     

Measurement of light within thin plant tissues with fiber optic microprobes

Vogelmann, T. C., Knapp, A. K., McClean, T. M. and Smith, W. K. 1988. Measurement of light within thin plant tissues with fiber optic microprobes. - Physiol. Plant. 72: 623–630.
The measurement of light with fiber optic microprobes has been extended to thin (200–300 μm) plant tissue samples. To test the method, light measurements were made in thin aqueous films and paradermal sections from 10-day-old etiolated Cucurbita pepo L. cv. Fordhook cotyledons. The measurements obtained were highly reproducible. Paradermal sections of spongy mesophyll that were irradiated with collimated light scattered light more effectively than the palisade layer of intact cotyledons. These results demonstrate that different plant tissues have different light scattering characteristics. The successful extension of the fiber optic microprobe technique to thin systems makes it possible to examine the optical properties of different cell layers within leaves and other plant organs.