耕作方式对岩溶区甘蔗地土壤优先流特征的影响

岩溶区特殊的岩性地质条件,使土壤优先流现象广泛发生。以广西岩溶区内的典型农地甘蔗地作为研究对象,利用野外染色示踪技术和图像解析方法,分别对传统耕作(CT)和粉垄耕作(SRT)方式下的田间土壤优先流特征进行分析,揭示耕作方式对岩溶区甘蔗地土壤优先流的发生及其空间发展变化的影响。结果表明:①在相同外部供水条件下,传统耕作甘蔗地优先流运动分化程度相对较高,多呈指状形式,且平均湿润锋下渗深度为43.19 cm,显著大于粉垄耕作(P0.05),而粉垄耕作甘蔗地优先流以横向运动形式为主,表现为团块状湿润锋形式;②粉垄耕作甘蔗地土壤优先流发生时间显著滞后于传统耕作(P0.05),是其1.67倍;③随土壤深度的增加,两种耕作方式下的甘蔗地土壤优先流发育程度总体呈现先增加后降低的变化趋势,但粉垄耕作甘蔗地优先流比(70.72%)和长度指数(527.12%)均显著小于传统耕作甘蔗地(P0.05),且在土壤空间中对应的染色形态变异系数(1.19)是传统耕作的1.38倍,优先流发育程度显著低于传统耕作甘蔗地。粉垄耕作与传统耕作方式相比,在一定程度上降低了田间土壤优先流现象,改善了田间土层中的水肥状况。     

SRT1720 enhances maturity and quality of oocytes in aged mice

This study aims to investigate the morphology and distribution of mitochondria, spindles, and chromosomes in oocytes of aged mice and examine the effects of SRT1720 on oocyte maturation. C57BL/6J mice were divided into young (4–8 weeks) and aged groups (48–52 weeks). In vitro maturation media contained (0.05, 0.1, and 1.0 μM) SRT1720 and 0.1-μM dimethyl sulfoxide (DMSO control). The rate of chromosome misalignment and spindle misorientation in oocytes of aged mice were significantly higher than that of young mice (P < 0.01). Fluorescence intensity of mitochondria from oocytes of aged mice was significantly lower than that of young mice (P < 0.01). SRT1720 at 0.1 μM significantly improved oocyte maturation, fertilization, and blastocyst formation in aged mice compared with young mice (P < 0.01). Additionally, immunofluorescence intensity of mitochondria, normal spindle morphology, and chromosome alignment were notably enhanced with SRT1720 when compared with the DSMO control group for metaphase II (MII)-stage oocytes matured in vitro (P < 0.01); 0.1-μM SRT1720 enhanced the expression level of SRIT1 in oocytes from aged mice. In summary, the aged mice oocytes showed increased nuclear and cytoplasmic defects, whereas SRT1720 enhanced oocyte maturation and quality. We concluded that 0.1-μM SRT1720 was an appropriate concentration for in vitro maturation media.     

The Research of Using Energy Metabolism Equation to Calculate the Sludge Retained Time

Substantially, the process of biological treatment for wastewater is the process of bacterial energy metabolism. In this paper, from the viewpoint of energy and based on the conservation of mass and energy, an energy metabolism equation is constructed. Through the experimentation, the parameters in equation are measured. Through this equation the reason for SRT choice of activated sludge system is explained from the viewpoint of microcosmic. This equation is adaptable to optimizing the SRT of activated sludge system in the condition of low-organic load thereby to optimizing the energy distribution of activated sludge system for energy saving     

Outcome of intensity‐modulated radiation therapy‐based stereotactic radiation therapy for treatment of canine nasal carcinomas

Stereotactic radiation therapy (SRT) has emerged as a convenient definitive treatment modality in veterinary medicine, but few studies exist evaluating outcome with treatment for canine nasal tumors, and no studies report the treatment of one single tumor histotype. This retrospective, observational study evaluates toxicity, response, and survival in 17 dogs with nasal carcinomas treated with SRT. Dogs received a median of 3000 centigray in three fractions via 6‐MV linear accelerator. Eighty‐eight percent of patients (n = 15) demonstrated clinical benefit. Of dogs with repeated CT imaging (n = 10), 60% (n = 6) achieved a partial response and 10% (n = 1) achieved a complete response. Median progression‐free survival (PFS) was 359 days. Median survival time (MST) was 563 days. Among dogs evaluable for acute toxicity, 50% (n = 10) developed low grade toxicity (grade 1, n = 4; grade 2, n = 1). No patients developed grade 3 toxicity. 16 dogs (87%) evaluable over the long term developed signs consistent with possible late toxicity. The majority of late toxicities were mild (alopecia, hyperpigmentation, and leukotrichia n = 10; ocular discharge and keratoconjunctivitis sicca n = 5). Thirty‐seven percent of patients (n = 6) developed seven possible grade 3 late toxicities (blindness, n = 3; fistula, n = 1; seizures, n = 3), which were difficult to distinguish from progressive disease in most patients. Of the prognostic factors evaluated (demographics, tumor stage, dosimetric data, epistaxis, facial deformity, clinical response, image‐based response, nonsteroidal anti‐inflammatory drugs, and chemotherapy), only clinical response was a positive prognostic factor on MST (P < .00). No factors were found to be significantly associated with PFS.     

反应器类型对生物厌氧发酵产氢的影响研究进展

利用有机废水或废弃物厌氧发酵制取氢气可以同时达到除废和产能的双重目的,是近年来生物质能的研究热点。产氢反应器的类型会影响反应器内产氢菌的数量和种类以及微生物与底物之间的传质作用,进而影响产氢系统的稳定性和产氢效果。对厌氧产氢悬浮细胞系统和固定化细胞系统（颗粒污泥、生物膜、微生物包埋体）保留生物量的效果进行了对比,总结了连续搅拌釜式反应器（CSTR）、厌氧序批反应器（ASBR）、上流式厌氧污泥床（UASB）、膨胀颗粒污泥床（EGSB）、厌氧填充床、厌氧流化床（AFBR）以及复合生物反应器等不同反应器类型对厌氧产氢的影响,并提出了一些建议与展望,以期为以后的研究提供指导作用。     

泥龄对反硝化除磷效能的影响

在厌氧/缺氧(A/A)SBR反应器中考察了污泥龄对反硝化除磷系统效能的影响。结果表明,泥龄对污水中有机物的降解并无明显影响,进水COD基本上都能降解完全;系统脱氮效能受SRT影响不大,只要系统保持SRT大于多数反硝化菌的时代时间,脱氮率基本在90%以上。除磷效果则对SRT变化较为敏感,SRT过低和过高都不利于系统的稳定运行,当SRT为18 d时是维持污泥浓度和除磷效果的最佳结合点。     

Efficacy of stereotactic radiation therapy for the treatment of confirmed or presumed canine glioma

Intracranial gliomas are the second most common brain tumour in dogs. Radiation therapy provides a minimally invasive treatment option for this tumour type. Earlier publications reporting on the use of non-modulated radiation therapy suggested a poor prognosis for dogs with glioma, with median survival times ranging between 4 and 6 months; more recent literature utilizing stereotactic radiation therapy (SRT) demonstrates that the prognosis for canine gliomas may be more promising, with survival times closer to 12 months. A single institution retrospective study was performed between 2010 and 2020 investigating the outcomes of dogs with biopsy-confirmed glioma or a presumptive diagnosis of intra-cranial glioma based on MRI characteristics that were treated with SRT. Twenty-three client-owned dogs were included. Brachycephalic breeds were overrepresented, totalling 13 dogs (57%). SRT protocols included 16 Gy single fraction (n = 1, 4%), 18 Gy single fraction (n = 1, 4%), 24 Gy in 3 daily fractions (n = 20, 91%), or 27 Gy in four daily fractions (n = 1, 4%). Twenty-one dogs (91%) had improvement of their presenting clinical signs following SRT. Median overall survival time (MST) was 349 days (95% CI, 162–584). Median disease specific survival time was 413 days (95% CI, 217–717). When SRT is incorporated into the management plan for dogs with confirmed or presumed intracranial glioma, a median survival time of approximately 12 months may be achievable.     

高校SRT及大学生科研素质全程化培养模式的研究

从国内外大学生科研训练的现状出发,分析了存在的问题,针对高校SRT在教育观念、培养模式、课程结构、经费上的制约因素,提出本科生科研训练的指导思想、计划目标、组织形式和实施方法,并对目前亟待解决的问题做了初步探讨。