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41.
BACKGROUND: Two field trials growing Jerusalem artichoke (Helianthus tuberosus L.) are discussed. Twenty genetic variants were compared in order to find genotypes suitable for Norwegian production. A second trial investigated the above‐ground part of early and late variants. RESULTS: The highest yield (28.7 t ha?1) and highest amount of tubers per plant was obtained in early variants, e.g. the white Tysnes gave 1.72 kg tubers plant?1. Early variants had a markedly lower portion of smooth tubers. Late variants gave the most preferable tuber shape, but low yield. Only a weak correlation was found between dry matter content and total content of fructo‐oligosaccharides (FOS) (r = 0.255) in the tubers. The mean content of FOS including sucrose through all variants was found to be 116 g kg?1 fresh weight (FW) or 550 g kg?1 dry weight (DW). The average chain length of FOS in the tubers was found to be DP3.9. There was no difference in tuber FOS content between early and late variants. The highest above‐ground amount biomass was found for the late variants when harvested in September. The content of soluble carbohydrates was found to be highest in stalks in August (sucrose and FOS major compounds). CONCLUSION: Early variants give the highest tuber yield under Norwegian growing conditions. Late variants give highest above‐ground biomass. Copyright © 2010 Society of Chemical Industry  相似文献   
42.
Hydrolytic degradation at elevated temperatures is a key reason for failure in offshore flexible risers. In this article, the aging of polyamide 11 in deoxygenated water at 90°C and 120°C was studied. Tensile and dynamic mechanical thermal analysis tests were performed to measure changes in mechanical properties. Viscometry, gravimetric measurements, differential scanning calorimetry, and thermogravimetric analysis were used to link these properties with morphological changes. General trends are increased stiffness, tensile strength, and glass transition temperature as well as decreased glassy state damping efficiency with increased aging times. Changes can be initially ascribed to plasticizer depletion and then to interplay between molecular weight decrease and crystallinity increase. Viscosity at hydrolysis equilibrium indicates that brittle failure typically involves oxidation or UV exposure. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41971.  相似文献   
43.
Fifty-five to two hundred CGG repeats (called a premutation, or PM) in the 5′-UTR of the FMR1 gene are generally unstable, often expanding to a full mutation (>200) in one generation through maternal inheritance, leading to fragile X syndrome, a condition associated with autism and other intellectual disabilities. To uncover the early mechanisms of pathogenesis, we performed metabolomics and proteomics on amniotic fluids from PM carriers, pregnant with male fetuses, who had undergone amniocentesis for fragile X prenatal diagnosis. The prenatal metabolic footprint identified mitochondrial deficits, which were further validated by using internal and external cohorts. Deficits in the anaplerosis of the Krebs cycle were noted at the level of serine biosynthesis, which was confirmed by rescuing the mitochondrial dysfunction in the carriers’ umbilical cord fibroblasts using alpha-ketoglutarate precursors. Maternal administration of serine and its precursors has the potential to decrease the risk of developing energy shortages associated with mitochondrial dysfunction and linked comorbidities.  相似文献   
44.
The precipitate microstructure and vacancy distribution in Al-Mg-Si alloys with different amounts of solute and different heat treatments were investigated by transmission electron microscopy and muon spin relaxation measurements. A high amount of vacancies is normally present in Al-Mg-Si alloys as these bind to atomic clusters. We observe these vacancies to leave the material not before over-aging at very high temperatures such as 623 K (350 °C), meaning that vacancies do not bind to incoherent over-aged precipitates. For samples only stored at room temperature after solution heat treatment, a reduction of muon trapping was found at a temperature of 140 K (?133 °C) when reducing the amount of solute in the alloy. This might be connected to a lower number density of Cluster (1), which contrary to Cluster (2) do not nucleate precipitates upon further aging of the material.  相似文献   
45.
It is demonstrated that good thermal stability in Al-Mg-Si-Cu aluminum alloys correlates with a high density of fine lath-shaped, Cu-containing, disordered L-precipitates. Alloys optimized for L retained hardness above 90 HV after 3 weeks over-aging at 473 K (200 °C). Further improvement was achieved by substituting Si by Ge in one alloy. High-angle annular dark-field scanning transmission electron microscopy showed that at peak-hardness conditions, L coexists with more common needle-shaped precipitates, often with Cu-enriched interfaces.  相似文献   
46.
Type IIB von Willebrand disease (vWD) is characterized by a selective loss of high molecular weight von Willebrand factor (vWF) multimers in plasma due to their abnormally enhanced reactivity with platelets. Several missense mutations in the platelet glycoprotein Ib (GPIb) binding domain of vWF were recently characterized that cause type IIB vWD. The effect of type IIB mutation Arg(545)Cys on vWF binding to platelet GPIb was studied using recombinant wild type (rvWFWT) and mutant rvWFR545C expressed in COS-7 cells. In the absence of ristocetin, 50% of rvWFR545C bound spontaneously to platelet GPIb and the binding increased to 70% in the presence of 0.2 mg/ml ristocetin; rvWFWT did not bind significantly under either condition. Botrocetin-induced binding of rvWFR545C was only slightly increased compared to rvWFWT. These data demonstrate that the Arg(545)Cys mutation increases the affinity of vWF for GPIb, resulting in the characteristics gain-of-function type IIB vWD phenotype.  相似文献   
47.
In Al–Mg–Si alloys, additions of only a few weight percent of Mg and Si enable formation of hardening precipitates during heat treatment. The precipitation is complex and is influenced by chemical compositions and thermo‐mechanical treatment. Structural analysis at the atomic scale has played an important role for understanding the Al–Mg–Si system. This review paper gives a summary of the influence of elements on the precipitate structures of Al–Mg–Si alloys at the atomic scale. The structures are modified by small additions of different elements, but all the encountered precipitates are structurally connected with the Si network, except for the main hardening phase which exhibit a partially discontinuous Si network. The influence of the selected elements (Li, Cu, Zn, Ge, Ag, Ni, Co, and Au) is discussed in detail.
  相似文献   
48.
Objective: Transference interpretation is considered as a core active ingredient in dynamic psychotherapy. In common clinical theory, it is maintained that more mature relationships, as well as a strong therapeutic alliance, may be prerequisites for successful transference work. In this study, the interaction between quality of object relations, transference interpretation, and alliance is estimated. Method: One hundred outpatients seeking psychotherapy for depression, anxiety, and personality disorders were randomly assigned to 1 year of weekly sessions of dynamic psychotherapy with transference interpretation or to the same type and duration of treatment, but without the use of transference interpretation. Quality of Object Relations (QOR)–lifelong pattern was evaluated before treatment (P. H?glend, 1994). The Working Alliance Inventory (A. O. Horvath & L. S. Greenberg, 1989; T. J. Tracey & A. M. Kokotovic, 1989) was rated in Session 7. The primary outcome variable was the Psychodynamic Functioning Scales (P. H?glend et al., 2000), measured at pretreatment, posttreatment, and 1 year after treatment termination. Results: A significant Treatment Group × Quality of Object Relations × Alliance interaction was present, indicating that alliance had a significantly different impact on effects of transference interpretation, depending on the level of QOR. The impact of transference interpretation on psychodynamic functioning was more positive within the context of a weak therapeutic alliance for patients with low quality of object relations. For patients with more mature object relations and high alliance, the authors observed a negative effect of transference work. Conclusion: The specific effects of transference work was influenced by the interaction of object relations and alliance, but in the direct opposite direction of what is generally maintained in mainstream clinical theory. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
49.
Obese children (aged 8–12 yrs) and parents from 53 families were randomly assigned to 3 groups: diet, diet plus exercise, and no-treatment control. At 6 mo, parents and children in both treatment groups had equal and significantly better weight change than members of the control group. At 1 yr, however, parents given diet plus exercise showed better weight losses than parents given diet alone. No treatment group differences were found for children after 1 yr. Parent and child weight changes observed during the 1st 6 mo of treatment were highly correlated, but those observed during Months 6–22 were uncorrelated. Discriminant analyses showed that initial relative weight was the best predictor of 12-mo relative weight for both parents and children but that exposure to the exercise program during treatment was a predictor of maintenance of nonobesity. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
影像融合在滨海湿地遥感监测中具有重要作用,然而滨海湿地区域多以水体、植物等为主,地物复杂多变,导致现有融合方法易产生光谱畸变且鲁棒性往往较差,难以满足滨海湿地的长时序动态监测需求。为此,提出基于空—谱质量评价的全色/多光谱影像融合方法SSQI_ PANSHARP,所提融合模型以融合影像的空—谱质量评价为导向,集成多种融合方法在空间增强和光谱保真方面的互补优势,满足滨海湿地长时序遥感监测对融合方法鲁棒性的需求。以杭州湾滨海湿地为研究区域,利用1999~2018年Landsat-7、Landsat-8卫星20年影像数据,从定性、定量以及滨海湿地典型地物光谱指数NDVI、NDWI等多方面,对提出方法进行充分验证,并在此基础上均匀抽取相近季度3期数据,对杭州湾滨海湿地近20年间土地覆盖类型,进行宏观长时序动态监测分析。研究结果表明,SSQI_PANSHARP方法在滨海湿地区域中的光谱保真度、空间结构信息增强效果表现较好,且鲁棒性强,适合于滨海湿地的长时序监测需求。监测结果显示,杭州湾南岸滨海湿地2010年后建筑用地比例上升,区域内池塘水田明显增加,农田绿地有所下降。  相似文献   
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