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641.
Deregulation of dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) plays a significant role in developmental brain defects, early-onset neurodegeneration, neuronal cell loss, dementia, and several types of cancer. Herein, we report the discovery of three new classes of N-heterocyclic DYRK1A inhibitors based on the potent, yet toxic kinase inhibitors, harmine and harmol. An initial in vitro evaluation of the small molecule library assembled revealed that the core heterocyclic motifs benzofuranones, oxindoles, and pyrrolones, showed statistically significant DYRK1A inhibition. Further, the utilization of a low cost, high-throughput functional genomic in vivo model system to identify small molecule inhibitors that normalize DYRK1A overexpression phenotypes is described. This in vivo assay substantiated the in vitro results, and the resulting correspondence validates generated classes as architectural motifs that serve as potential DYRK1A inhibitors. Further expansion and analysis of these core compound structures will allow discovery of safe, more effective chemical inhibitors of DYRK1A to ameliorate phenotypes caused by DYRK1A overexpression.  相似文献   
642.
Die universellen Energiekennzahlen für Deutschland beinhalten bis dato 1/4 Million Gebäude‐Energieverbrauchskennzahlen der BRUNATA‐METRONA‐Gruppe aus den vergangenen sechs Jahren. Deren Datenaufbereitung umfasst die rückwirkende Revision respektive Normierung aller Energiekennzahlen anhand neuer ortsgenauer Klimafaktoren des Deutschen Wetterdienstes. Eine Auswahl von 110.000 Energiekennzahlen von gas‐ und ölbeheizten Gebäuden — davon etwa die Hälfte mit Baujahr nach 1977 — werden statistisch gemäß ihrer Kennzahlenentwicklung nach Baualtersklassen aufgeschlüsselt. Betrachtet wurden dabei nur nominell wärmetechnisch unsanierte Mehrfamilienhäuser bis 1994 und Neubauten ab 1995. Es wird belegt, dass die Mediane der heutigen Energiekennzahlverteilungen der bis in die 1960‐er Jahre gebauten Gebäude relativ konstant um 155 kWh/(m2a) liegen. Für diesen Bauzeitraum fallen die Energiekennzahlen für rund 90 % des Bestandes (5 bis 95 % Quantil) zwischen 100 und 260 kWh/(m2a). Seitdem fallen die Mediane stetig auf aktuell bis 85 kWh/(m2a). Der stärkste relative Rückgang ergibt sich für die Baujahre von 1994 nach 1995 mit Inkrafttreten der Wärmeschutzverordnung 1995. Die Standardabweichungen der Verteilungen haben sich gegenüber den Gebäuden aus den 1960‐er Jahren von über 50 kWh/(m2a) bis auf heute an nähernd 25 kWh/(m2a) etwa halbiert. Eine Gegenüberstellung der empirisch ermittelten Verbrauchskennzahlverteilungen mit den typischen Mindestanforderungen der vergangenen Wärmeschutzverordnungen und aktuellen Energieeinsparverordnungen schließen sich an. Mathematische Parametrierungen der empirischen Kennzahlverteilungen für Modell‐ und Hochrechnungen der Energieeffizienzentwicklung werden mitgeliefert. Universal Energy ratings for Germany — (Part 2): Evolution of rating distributions according to year of building construction. To date, “Universal Energy Ratings” for Germany contain about a quarter of a million energy consumption ratings recorded by the BRUNATA METRONA Group within the recent six year period. Data processing comprises a retro perspective review and normalisation of all energy ratings according to new, localised climate factors from the German weather service. A subset of 110.000 energy ratings concerning gas‐ and oil‐heated buildings only — half of those built past 1977 — has been analysed statistically by creating energy rating distributions depending on construction year, focussing exclusively on unrenovated objects (according to 1995 standards) built prior to 1995 and new buildings constructed in 1995 or later. It is shown, that the median values of rating distributions from about 1900 up into the 1960ies appear relatively constant around 155 kWh/(m2a). For building construction years within this time interval 90 % of today’s energy ratings (5 % to 95 %‐percentiles) fall into the range between 100 and 260 kWh/(m2a). For construction years after the mid 1960ies the median values continuously decrease to about 85 kWh/(m2a) today. Their corresponding standard deviations decreased by a factor of two from above 50 kWh/(m2a) to about 25 kWh/(m2a). The most distinct relative decrease occurred between 1994 and 1995 when the WSVO’95 was activated. This work adds a direct comparison between the recorded today energy ratings and the typical requirement levels of the various heat insulation regulations, WSVO, and Building Energy Conservation Ordinances, EnEV, concerning building construction years starting from 1977. We also present parameterization functions for the most important rating distributions that could be utilized for general model calculations and extapoletions to picture future energy efficiency evolution.  相似文献   
643.
In wet-oxidative gas desulfurization processes, absorbed H2S is directly converted to sulfur by a redox catalyst dissolved in a circulating scrubbing solution. High flexibility is achieved through the availability of different catalyst classes. In this work, a process based on the Takahax process was investigated in a pilot plant under industrially relevant conditions with coke oven gas. A stable plant operation without sulfur precipitation was achieved by a suitable choice of the operating conditions. The solid-free operating window was determined and a sulfur redissolution strategy developed.  相似文献   
644.
A variety of substituted schiff base complexes of the composition (“salen”)ZrCl2(thf) ( 1 – 21 ) were synthesized, with methylalumoxane (“MAO”) activated and used for a systematic study of their catalytic activity towards hexa‐1,5‐diene (“salen”: substituted salicylidene–ethylene‐iminato ligands). Main product of the catalytic cycle is methylenecyclopentane. Dimers are only formed in minor amounts. The catalytic activity and selectivity of the Ziegler–Natta systems strongly depend on the nature and the position of the peripheric substituents in the Schiff base ligands. Electron‐withdrawing substituents in para‐position to the phenolato oxygen (5‐position) decrease the catalytic activity. Improved activity and selectivity were obtained with electron‐donating substituents in 5‐position. Altering the ethylene bridge causes a lowering of the activity or inactivation. According to the x‐ray analysis the metal center in the related complex (L)ZrCl2 ( 22 ) (L: N′,N′‐bis(ethylene)‐N′‐methyl‐N,N′′‐bis(benzoylacetonato‐imine) has a pentagonal‐bipyramidal environment. The pentadentate schiff base ligand lies in the plane, and both chloro groups occupy the axial positions. In contrast to the catalytically active salene complexes 22 can not rearrange to form a species in which the both chlorides are cis to each other. Consequently 22 is catalytically inactive.  相似文献   
645.
The effect of a novel heat treatment, that is, aging under superimposed external stress, on the fatigue performance and microstructural evolution of a high-strength aluminum alloy (EN AW-7075) is presented. Stress aging, a combination of heat treatment and superimposed external stress, can enhance the mechanical properties of EN AW-7075 under monotonic loading due to the acceleration of precipitation kinetics. Scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) reveal that a longer aging time and the presence of superimposed stress both promote the formation and growth of precipitates, that is, the precipitation of strengthening η´ precipitates. This is confirmed by differential scanning calorimetry (DSC) heating experiments of stressless and stress-aged states. Furthermore, stress aging leads to a reduction of dimensions of precipitate-free zones near grain boundaries. Cyclic deformation responses (CDRs) and half-life hysteresis loops are evaluated focusing on the low-cycle fatigue (LCF) performance of different conditions. A noticeable cyclic hardening seen in case of the specimens aged for a short time indicates the occurrence of dynamic strain aging (DSA). Eventually, stress aging allows for an enhancement of the monotonic mechanical properties of EN AW-7075 without degrading the cyclic performance in the LCF regime.  相似文献   
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