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101.
102.
Martin-Vaquero P da Costa RC Echandi RL Sammet CL Knopp MV Sammet S 《Research in veterinary science》2012,93(1):427-429
The purpose of this study was to evaluate the feasibility of proton magnetic resonance spectroscopy (1H MRS) to study the concentration of metabolites in the brain of dogs at 3.0 and 7.0 T. Four healthy male beagles were scanned using 3.0 T and 7.0 T human magnetic resonance imaging (MRI) units. The results obtained showed that all dogs had excellent quality spectra for a small (1 cm3) and large (8 cm3) voxel at 3.0 T, whereas only 2 dogs had high quality spectra at 7.0 T due to insufficient water suppression. 1H MRS at 3.0 T appears to be a reliable method to study metabolite concentrations in the canine brain. The development of more advanced water suppression techniques is necessary to improve the results at 7.0 T. 相似文献
103.
Development of a teleoperation system for agricultural vehicles 总被引：1，自引：0，他引：1
N. Murakami A. Ito Jeffrey D. Will Michael Steffen K. Inoue K. Kita S. Miyaura 《Computers and Electronics in Agriculture》2008,63(1):81-robotics
A teleoperation system for a hydro-static transmission (HST) drive crawler-type robotic vehicle is described in this paper. The system was developed to satisfy the needs of various farm operations and teleoperation in unknown agricultural fields. The controller has a layered architecture and supports two degrees of cooperation between the operator and robot, direct and supervisory control. The vehicle can travel autonomously by using an RTK-GPS and a fiber-optic gyroscope during supervisory control, and the operator interface also provides a field navigator based on Google Map technology. The vehicle's position and heading direction was capable of 1 Hz update using precise satellite image maps. The results of field tests using direct control showed that it is difficult for the operator to control the movement of the vehicle along the target lines. On the other hand, the vehicle could travel in a straight line with a maximum lateral error of 0.3 m by using supervisory control. 相似文献
104.
105.
Gerd Wessolek Björn Kluge Steffen Trinks Michael Facklam Olaf Zeuschner 《Journal of Soils and Sediments》2018,18(2):481-493
Purpose
Wastewater irrigation is still a common practice in many cities worldwide. After ending the wastewater irrigation, the question arises as to how the highly polluted areas can be reused. Mostly, the remediation costs for liming or adding synthetic soil conditioners are too high for decision makers, often leading to unattractive wastelands in neighboring suburbs. This story shows how part of a former wastewater disposal field in Berlin (Germany) was remediated by adding and mixing loam-rich glacial until excavated from subway construction work. The remediation led to long-term improvements of soil and landscape, which nowadays is an attractive forested recreation area. Part of this landscape is used as an ecological lab for research, art, and education.Materials and methods
The article summarizes the results of soil analysis of the contamination status and remediation technique over the last 2 decades. We collected and reevaluated historical data, research results, technical reports, and graphic materials concerning the wastewater disposal field in Berlin, Germany.Results and discussion
The remediation concept without adding any synthetic substances was a successful soft technology leading to (i) a reduction of the long-term groundwater risk, (ii) an immobilization of the trace element concentration in the soil solution, and (iii) a reduction of the metal uptake by plants. Remediation led to much better conditions for plant growth, soil fauna, and microbiological activity, which improved the environment in a sustainable way. The implementation of a new landscape concept combining ecology, culture, and art totally changed the character of the landscape from former stinking wastewater fields to present-day attractive sites that can be used for many purposes.Conclusions
The remediation of the former wastewater disposal fields, using natural glacial till materials rich in clay and silt, became a “story of success.” However, a remediation project of this type and scope only becomes reality if all responsible actors in society participate continuously. We conclude that stakeholders should not focus only on remediation costs but also on the benefits for society: reclaiming waste sites significantly improves our well-being.106.
Generating genetic variation in narrow‐leafed lupin (Lupinus angustifolius L.) for plant architecture by ethyl methanesulfonate mutagenesis 
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下载免费PDF全文 Kristin Fischer Eicke Rudloff Steffen R. Roux Regine Dieterich Peter Wehling Wolfgang Friedt Brigitte Ruge‐Wehling 《Plant Breeding》2018,137(1):73-80
Narrow‐leafed lupin (NLL) is a source of protein and fibre with exceptional functional properties useful for a variety of purposes. In adapted NLL germplasm selected for low alkaloid contents, the genetic base is narrow, thus limiting fast breeding progress. In an EMS‐based mutagenesis programme, we have treated 40,000 seeds of cv. ‘Boruta’ and obtained a variety of phenotypic mutant lines expressing novel growth types with altered plant height and/or branching. In 3‐year field trials at two locations, three of these lines exhibited significantly improved grain yield components compared to the cv. ‘Boruta’. Growth types of these promising lines were shown to be inherited in a monogenic recessive manner and should, thus, be easily fixable by breeding. 相似文献
107.
Andrea Baumgarten Mathias Wilhelmi Kerstin Kalbantner Martin Ganter Reinhard Mischke 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(2):149-156
Background: Whole blood platelet aggregometry (impedance) is an important method to investigate platelet function disorders. Examination of hemostatic function in sheep is important with respect to their role as an animal model of human disease. Objective: The aim of this study was to evaluate and optimize selected methodological aspects (anticoagulant, agonist concentration) of impedance aggregometry in ovine blood using the new Multiplate 5.0 analyzer. Methods: Blood samples were collected in hirudin anticoagulant from 40 clinically healthy sheep. Samples from selected sheep were collected in citrate, with or without the addition of calcium chloride. The agonists adenosine diphosphate (ADP), collagen, ristocetin, arachidonic acid, and thrombin receptor‐activating peptide (TRAP) were added in several concentrations to induce aggregation. Results: Based on maximum aggregation values and internal precision, no significant difference was found between ADP concentrations of 3–10 μmol/L and collagen concentrations of 3–5 μg/mL (P>.05). The lowest interindividual variation of approximately 3–4‐fold was seen with 4 and 5 μmol/L ADP and 4 and 5 μg/mL collagen. Ristocetin, arachidonic acid, and TRAP did not induce significant aggregation at any concentration. Aggregation results were significantly lower when measured in citrate‐ vs hirudin‐anticoagulated blood, regardless of the presence of calcium chloride. Conclusions: Our results indicate that the multiplate impedance aggregometer is suitable for the measurement of platelet aggregation in sheep using optimal agonist concentrations of 4–5 μmol/L ADP and 4–5 μg/mL collagen. Hirudin‐anticoagulated blood is the preferred sample material. 相似文献
108.
内蒙古萨拉乌苏河米浪沟湾MIS 5以来生态环境演变特征 总被引：1，自引：0，他引：1
通过对毛乌素沙漠南缘萨拉乌苏河流域米浪沟湾地层中有机质含量(TOC)和饱和烃分布特征,以及沉积物中碳酸盐碳氧同位素组成的分析,讨论了该地区末次间冰期以来生态环境的演变特征和过程。MIS5阶段为森林草原环境,气候比较湿润,河流径流量较大;MIS4和MIS2阶段气候干冷,以沙漠堆积为主,但MIS2在16.9-18.4kaBP期间有一次持续大约1.5ka的古环境适宜时期,森林草原发育;MIS3阶段气候温暖湿润,森林草原环境,湖泊发育;全新世早中期总体上向干旱方向发展,湖泊动荡短暂,为较少森林的草原环境。到晚全新世以沙漠沉积为主,成为与目前生态环境相似的干草原环境。该地区的生态环境演变特征反映出主要受冬夏季风变化控制,但如果西风环流加强时期植被也相对发育。 相似文献
109.
Thomas Kaupper Stefanie Hetz Steffen Kolb Sukhwan Yoon Marcus A. Horn Adrian Ho 《Biology and Fertility of Soils》2020,56(3):287-298
Oil palm plantations, irreversibly claimed primarily from tropical forest, carpet the landscape in Malaysia and Indonesia, the largest global producers of palm oil. The impact of forest conversion... 相似文献
110.
12个中国地方鸡种群体遗传结构及遗传多样性分析 总被引：24，自引：4，他引：24
利用29对微卫星引物对我国的12个地方鸡种进行群体遗传结构及遗传多样性评估，结果表明：每个座位的等位基因数从2到23不等，所有的12个群体均显示较高水平的杂合度，固始鸡最低，为0．4532，大骨鸡最高，为0．6271。鸡种间存在较大的遗传分化，16．7％的遗传变异源于品种间的差异。基于Reynolds’遗传距离的邻近（NJ）聚类图显示，12个群体可以分为2个主要的类群：重体型的鸡种首先聚在一起，然后轻体型鸡种加入。structure程序同时也被用于评价鸡种间的遗传关系，结果与NJ聚类法相似，重体型的鸡种首先与轻体型鸡种分成两类。 相似文献