Magnetic Resonance Signal Amplification by Reversible Exchange of Selective PyFALGEA Oligopeptide Ligands Towards Epidermal Growth Factor Receptors

The biorelevant PyFALGEA oligopeptide ligand, which is selective towards the epidermal growth factor receptor (EGFR), has been successfully employed as a substrate in magnetic resonance signal amplification by reversible exchange (SABRE) experiments. It is demonstrated that PyFALGEA and the iridium catalyst IMes form a PyFALGEA:IMes molecular complex. The interaction between PyFALGEA:IMes and H₂ results in a ternary SABRE complex. Selective 1D EXSY experiments reveal that this complex is labile, which is an essential condition for successful hyperpolarization by SABRE. Polarization transfer from parahydrogen to PyFALGEA is observed leading to significant enhancement of the ¹H NMR signals of PyFALGEA. Different iridium catalysts and peptides are inspected to discuss the influence of their molecular structures on the efficiency of hyperpolarization. It is observed that PyFALGEA oligopeptide hyperpolarization is more efficient when an iridium catalyst with a sterically less demanding NHC ligand system such as IMesBn is employed. Experiments with shorter analogues of PyFALGEA, that is, PyLGEA and PyEA, show that the bulky phenylalanine from the PyFALGEA oligopeptide causes steric hindrance in the SABRE complex, which hampers hyperpolarization with IMes. Finally, a single-scan ¹H NMR SABRE experiment of PyFALGEA with IMesBn revealed a unique pattern of NMR lines in the hydride region, which can be treated as a fingerprint of this important oligopeptide.     

Energy Efficiency Trade-Off Between Duty-Cycling and Wake-Up Radio Techniques in IoT Networks

Wireless Personal Communications - For robust monitoring, control and proper energy management of renewable energy sources (RES), wireless sensing networks (WSNs) are proved to be a vital solution....     

Activity-Directed Synthesis: A Flexible Approach for Lead Generation

Activity-directed synthesis (ADS) is a structure-blind, functional-driven molecular discovery approach. In this Concept, four case studies highlight the general applicability of ADS and showcase its flexibility to support different medicinal chemistry strategies. ADS deliberately harnesses reactions with multiple possible outcomes, and allows many chemotypes to be evaluated in parallel. Resources are focused on bioactive molecules, which emerge in tandem with associated synthetic routes. Some of the future challenges for ADS are highlighted, including the realisation of an autonomous molecular discovery platform. The prospects for ADS to become a mainstream lead generation approach are discussed.     

Evaluating the effects of frame of reference on spatial collaboration using desktop collaborative virtual environments

Spatial collaboration is an everyday activity in which people work together to solve a spatial problem. For example, a group of people will often arrange furniture together or exchange directions with one another. Collaborative virtual environments using desktop PCs are particularly useful for spatial activities when the participants are distributed. This work investigates ways to enhance distributed, collaborative spatial activities. This paper explores how different frames of reference affect spatial collaboration. Specifically, it reports on an experiment that examines different combinations of exocentric and egocentric frames of reference with two users. Tasks involve manipulating an object, where one participant knows the objective (director) and the other performs the interactions (actor). It discusses the advantages and disadvantages of the different combinations for a spatial collaboration task. Findings from this study demonstrate that frames of reference affect collaboration in a variety of ways and simple exocentric-egocentric combinations do not always provide the most usable solution.     

Technology combats disabilities

The author focusses on advances in equipment that offset physically functional limitations. He discusses how disabled and elderly people are using aids that enhance mobility (walking a certain distance, lifting a weight, or climbing stairs) as well as sensory faculties (seeing print, hearing conversation, and speaking intelligibly)     

Synthesis and thermal stability of ball-milled and melt-quenched amorphous and nanostructured Al-Ni-Nd-Co alloys

In this work the Al₈₅Ni₉Nd₄Co₂ alloy was used as a starting point for examining the possibility of forming bulk glassy Al-based materials by combining rapid quenching and ball milling techniques. Fine glassy powders were obtained by ball milling melt-spun amorphous ribbons using a severe cryogenic processing regime. The thermal stability data of the powders as obtained by constant-rate heating and isothermal DSC experiments together with viscosity measurements are discussed with respect to feasible consolidation conditions. The powder compaction was done by two methods (uni-axial hot pressing and extrusion) at 513 K for up to 15 min. Only the uni-axial hot pressing led to bulk Al₈₅Ni₉Nd₄Co₂ samples with similar glassy structure and Vickers microhardness values comparable to those of the initial melt-spun ribbons.     

Alpha induced reactions on Sn: An experimental study of excitation functions and possible production pathways

In the frame of a systematic study of light ion induced threshold reactions on natural tin (Sn) excitation functions for alpha particles induced reactions are presented in a 12–38 MeV energy domain. Using a stacked foil activation method the following radioisotopes were identified: ¹¹⁶Te, ¹¹⁷Te, ¹¹⁸Te, ¹¹⁹Te, ¹²¹Te, ¹²³Te, ¹¹⁷Sb, ¹¹⁸Sb, ¹²⁰Sb, ¹²²Sb, ¹²⁴Sb, ¹²⁶Sb, ¹¹⁷Sn, ¹¹¹In. The experimental cross sections for these isotopes are presented for the first time in this energy range and a direct comparison with values calculated with the ALICE-IPPE code is discussed. Possible use of these data for production of some isotopes relevant in nuclear medicine is suggested.     

基于计算机的材料性能测试

 恩斯特马赫研究所(EMI)的弗劳恩霍费尔瞬时动力学研究所通过多功能动态材料试验台、碰撞和冲击装置、冲击管装置进行实验以及数值模拟，从事材料动态特性研究，并将所确定的动态材料数据用于未来新材料的优化设计。     

Demonstration of discrete secreted and membrane-bound ocular mucins in the dog

Our aims were to separate and characterize secreted canine ocular mucins, and to provide definitive evidence of membrane-bound mucins at the canine ocular surface. Mucus was collected by suction from the ocular surface of normal dogs and dispersed in guanidine hydrochloride and a cocktail of protease inhibitors. Caesium chloride density gradient centrifugation separated secreted mucins from membranes, which were collected from the top of the gradients. Membranes were extracted with octyl glucoside and screened using lectins and anti-mucin antibodies. Gradient fractions containing secreted mucins were constituted into pools on the basis of differential lectin and antibody staining. High molecular weight material from each pool was purified by gel filtration. This material, and the membrane extract, were reduced and alkylated. Vacuum blotting of separated materials after agarose gel electrophoresis was used to compare subunit structure. Density gradient profiles indicated three principal secreted glycoprotein peaks: one staining strongly with anti-mucin antibodies. Gel filtration demonstrated that each contained high molecular weight material. Vacuum blots demonstrated the presence of two secreted glycoproteins with differently sized subunits. On the basis of buoyant density, one of these may be lipid complexed. Membrane extracted material stained with anti-mucin antibodies, and vacuum blotting of this material provided evidence for two membrane-bound components. In conclusion, we have shown that normal canine ocular mucus contains two secreted mucins, each exhibiting different subunit structure; one of these mucins may undergo lipid complexation. Normal canine ocular mucus also contains two membrane-bound mucins: one of which is unique among membrane mucins in showing subunit structure.