A Click-Chemistry-Based Enrichable Crosslinker for Structural and Protein Interaction Analysis by Mass Spectrometry

Mass spectrometry is the method of choice for the characterisation of proteomes. Most proteins operate in protein complexes, in which their close association modulates their function. However, with standard MS analysis, information on protein–protein interactions is lost and no structural information is retained. To gain structural and interactome data, new crosslinking reagents are needed that freeze inter- and intramolecular interactions. Herein, the development of a new reagent, which has several features that enable highly sensitive crosslinking MS, is reported. The reagent enables enrichment of crosslinked peptides from the majority of background peptides to facilitate efficient detection of low-abundant crosslinked peptides. Due to the special cleavable properties, the reagent can be used for MS² and potentially for MS³ experiments. Thus, the new crosslinking reagent, in combination with high-end MS, should enable sensitive analysis of interactomes, which will help researchers to obtain important insights into cellular states in health and diseases.     

Overview of Steel Bridges Containing High Strength Steel

The use of high strength steel has the potential to reduce the amount of steel used in bridges and thereby, facilitate a more sustainable construction. A survey of existing bridges built using high strength steel is presented in this paper with emphasis on the Swedish bridge stock. The survey aimed at identifying the steel grades that were used and where in the cross-section they have been used. A case study on the influence of fatigue shows that today’s regulations make it more difficult to use high strength steel in comparison to previous regulations.

     

In situ growth of well-dispersed CdS nanocrystals in semiconducting polymers

A straight synthetic route to fabricate hybrid nanocomposite films of well-dispersed CdS nanocrystals (NCs) in poly[2-methoxy-5-(2''-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) is reported. A soluble cadmium complex [Cd(SBz)₂]₂·MI, obtained by incorporating a Lewis base (1-methylimidazole, MI) on the cadmium bis(benzyl)thiol, is used as starting reagent in an in situ thermolytic process. CdS NCs with spherical shape nucleate and grow well below 200°C in a relatively short time (30 min). Photoluminescence spectroscopy measurements performed on CdS/MEH-PPV nanocomposites show that CdS photoluminescence peaks are totally quenched inside MEH-PPV, if compared to CdS/PMMA nanocomposites, as expected due to overlapping of the polymer absorption and CdS emission spectra. The CdS NCs are well-dispersed in size and homogeneously distributed within MEH-PPV matrix as proved by transmission electron microscopy. Nanocomposites with different precursor/polymer weight ratios were prepared in the range from 1:4 to 4:1. Highly dense materials, without NCs clustering, were obtained for a weight/weight ratio of 2:3 between precursor and polymer, making these nanocomposites particularly suitable for optoelectronic and solar energy conversion applications.     

欧洲与北美制造的烧结青铜含油轴承性能的比较

多孔性青铜含油轴承是全世界都在生产的，最早与最无处不用的现代粉末冶金产品。然而，各地区产品之间仍存在着明显差异。近期发布的粉末冶金材料的全球标准ISO5755，其中有2个描述轴承材料性能的数据表。其中列举的几项关键性轴承特性和MPIF标准35或相应的ASTM标准中列出的轴承性能有所不同。因此，MPIF标准委员会进行一项小型试验，对标准90％（质量分数）Cu-10％（质量分数）Sn轴承的关键特性进行了对比。这项研究的样品零件来自欧洲与北美的大批量生产厂家。数据证实孔隙度与径向压溃强度不同，这种差异是原料粉与制造工艺的微妙差异所致。最终用户应该了解这些差异，和确认IS05755中列举的特性能满足他们对轴承的要求。     

Biochemical Characterization of Pyranose Oxidase from Streptomyces canus—Towards a Better Understanding of Pyranose Oxidase Homologues in Bacteria

Pyranose oxidase (POx, glucose 2-oxidase; EC 1.1.3.10, pyranose:oxygen 2-oxidoreductase) is an FAD-dependent oxidoreductase and a member of the auxiliary activity (AA) enzymes (subfamily AA3_4) in the CAZy database. Despite the general interest in fungal POxs, only a few bacterial POxs have been studied so far. Here, we report the biochemical characterization of a POx from Streptomyces canus (ScPOx), the sequence of which is positioned in a separate, hitherto unexplored clade of the POx phylogenetic tree. Kinetic analyses revealed that ScPOx uses monosaccharide sugars (such as d-glucose, d-xylose, d-galactose) as its electron-donor substrates, albeit with low catalytic efficiencies. Interestingly, various C- and O-glycosides (such as puerarin) were oxidized by ScPOx as well. Some of these glycosides are characteristic substrates for the recently described FAD-dependent C-glycoside 3-oxidase from Microbacterium trichothecenolyticum. Here, we show that FAD-dependent C-glycoside 3-oxidases and pyranose oxidases are enzymes belonging to the same sequence space.     

Synthesis from hyperproperties

We study the reactive synthesis problem for hyperproperties given as formulas of the temporal logic HyperLTL. Hyperproperties generalize trace properties, i.e., sets of traces, to sets of sets of traces. Typical examples are information-flow policies like noninterference, which stipulate that no sensitive data must leak into the public domain. Such properties cannot be expressed in standard linear or branching-time temporal logics like LTL, CTL, or $$\hbox {CTL}^*$$. Furthermore, HyperLTL subsumes many classical extensions of the LTL realizability problem, including realizability under incomplete information, distributed synthesis, and fault-tolerant synthesis. We show that, while the synthesis problem is undecidable for full HyperLTL, it remains decidable for the $$\exists ^*$$, $$\exists ^*\forall ^1$$, and the $${{ linear }}\;\forall ^*$$ fragments. Beyond these fragments, the synthesis problem immediately becomes undecidable. For universal HyperLTL, we present a semi-decision procedure that constructs implementations and counterexamples up to a given bound. We report encouraging experimental results obtained with a prototype implementation on example specifications with hyperproperties like symmetric responses, secrecy, and information flow.     

Population Ageing,the Intergenerational Conflict,and Active Ageing Policies – a Multilevel Study of 27 European Countries

In the scientific and the public debate demographic ageing is sometimes perceived as an unstoppable “grey tide” which will inevitably lead to a conflict between the old and young generation. In this paper we empirically evaluate whether we find any evidence for an intergenerational conflict in Europe and which factors might influence its severity. In particular, we answer the following questions. (1) Is there a conflict between the interests of the younger and the older generation? (2) Does the strength of the conflict increase with population ageing? And finally, (3) can a policy of Active Ageing, i.e. better integrating older generations into society, moderate the conflict? We answer these questions in a comparative study of 27 European countries using data from the Eurobarometer 2009. Our results show a moderate conflict between generations. Compared to spending preferences of the younger generation, older people are more likely to support increased spending for old age at the expense of educational spending. Contrary to expectation, generational conflict does not increase with population ageing. Linking country differences in the strength of the generational conflict to the degree of population ageing with multilevel regression techniques we do not find any evidence that the conflict is increasing In a final step of our analysis we evaluate the potential of generational policies - measured with the Active Aging Index - to mitigate the generational conflict. Intergenerational conflict is weaker when older people actively participate in the political life and are visible in society, suggesting Active Aging policies as a means to mitigate intergenerational conflict     

A study of suppression effect of oxygen contamination by bias voltage in reactively sputtered ZrN films

A scrupulous cleaning and degreasing of the deposition chamber allows to make a ZrN film with stoichiometry of 1.3 and to achieve a level of oxygen contamination equal to 5%. This film exhibits a low number of carriers estimated at N* = 3 × 10²¹ cm^− 3 and with a very high electrical resistivity value of about 10⁵ μΩ·m. This result points the way for further improvements in the quality of the material.This amount of oxygen contamination may be reduced in conditions in which only the oxygen will be removed without disturbing the zirconium presence in the film. A bias voltage value between 8 eV and 20 eV reduces the oxygen contamination.The ionic assistance is often proposed as a mean to minimize the oxygen contamination. However, one must consider the negative phenomena as re-sputtering, ion implantation, atom displacement and stress generation that introduce defects in the film and affect its properties. This work proposes a very low bias voltage value to control oxygen contamination. The bias voltage value is chosen higher than the nitrogen sputtering threshold energy and lower than the argon sputtering threshold energy. The re-sputtering phenomenon, far from being a problem, can be used to achieve the stoichiometry if one starts from a nitrogen-rich compound. In this way, ZrN_x is grown with x about 1, with an effective free electron concentration N* = 8.9 × 10²¹ cm^− 3. Furthermore its resistivity value is about 2 μΩ·m and the oxygen Secondary Ion Mass Spectrometry (SIMS) signal is similar to the noise signal.     

Temperature and Texture Development during High Speed Friction Stir Processing of Magnesium AZ31

The increasing demand for low weight structural materials yields a growing interest in Mg alloys processed at industrially interesting speeds. One aim of this study is to develop defect free welds in the velocity range of 1–10 m · min^?1. The resulting welds are subjected to temperature, microstructure and texture investigations. Energy input as well as temperature development under the tool are predicted using numerical models. Image correlation is used to evaluate distortion. The results show that while ensuring constant weld quality, the energy input, sample distortion and grain size can be decreased reaching a threshold at 5 m · min^?1. Thermal analysis reveal an asymmetry between AS and RS. The basal planes exhibits a shift from 0 to 45° into processing direction.     

追求能源效率是材料研发的动力

在发动机舱内的塑料必须能承受发动机舱内持续生高的温度.