Low temperature fluorescence spectra of atropisomeric perylene dyes

The site selection spectra of highly photostable perylene fluorescent dyes at 4.2 K in a glassy matrix of three different organic solvents (ethanol, methyl tetrahydrofuran, n-butyl acetate) are presented. The spectra ofthe two isomers are identical for a given solvent and only very minute differences are detectable between different solvents. We conclude that the influence of the matrix on the fluorescence spectra is of only minor importance. The influence of the orientation in the matrix is negligible

Corrosion Study of Current Collectors for Magnesium Batteries

The transition to renewable energy requires a significant amount of low-cost energy storage systems. Regarding batteries, magnesium provides a highly abundant raw material which is less sensitive to air in comparison to lithium, crucial to the mass production and safety. Promising candidates for intercalation materials on the cathode side are Prussian green FeFe(CN)6 with a electrochemical potential of around 0,9 V vs. Mg or the Chevrel phase Mo6S8 which shows a high specific capacity of around 120 mAh/g. Magnesium perchlorate-based electrolytes provide a practicable solution for fundamental work in the early stage of cathode research, yet are not compatible with Mg metal due to corrosion. Therefore, the organo-metallic all phenyl complex (APC) based electrolyte is a potential candidate for magnesium full cells. However, both systems contain highly reactive chloride species which cause severe corrosion of the current collector. In this work, potential materials for current collectors (carbon coated Al and Ni) are investigated applying linear sweep voltammetry, chronoamperometry and electrochemical impedance spectroscopy. A graphite based current collector is identified as the most promising candidate due to its high corrosion resistivity of 2 V vs. Mg/Mg2+ and low areal density, which helps to increase the energy density of practical Mg batteries

Ingestion of colostrum from specific cows induces Bovine Neonatal Pancytopenia (BNP) in some calves

Background: Since 2006, cases of haemorrhagic diathesis in young calves have been observed with a much higher incidence than previously known. The syndrome, now uniformly called Bovine Neonatal Pancytopenia (BNP), is characterized by multiple (external and internal) haemorrhages, thrombocytopenia, leukocytopenia, and bone marrow depletion. Although various infectious and toxicological causes of bleeding disorders in calves have been ruled out, the aetiology of BNP remains unknown. However, field observations have led to the hypothesis that the aetiological principle may be transmitted to calves via colostrum. The objective of the present study was to verify whether ingestion of colostrum from dams of known BNP calves can elicit signs of BNP and typical haematological findings in conveniently selected neonatal calves. Six such calves received one feeding of colostrum (or a mixture of colostrum batches) from dams of known BNP calves. As controls, another six conveniently selected calves from herds which had never had a BNP case received one feeding of colostrum from their own dams. Haematological and clinical parameters were monitored. Results: One of the six experimental calves never showed any haematological, clinical or pathological evidence of BNP. In the other five calves, thrombocyte and leukocyte counts dropped within a few hours following ingestion of colostrum. Of those, three calves developed clinical signs of BNP, their post-mortem examination revealed bone marrow depletion. Of the remaining two calves, a pair of mixed twins, marked thrombocytopenia and recurrent leukocytopenia was evident in one, in which only slight changes in the bone marrow were detected, while in the other thrombocyte counts dropped, but rebounded later, and no bone marrow changes were noted. Thrombocyte counts of the experimental calves were statistically significantly lower than those of the control calves at 2 hours post ingestion of colostrum and at every sampling point between 9 hours and 8 days postcolostral. Leucocyte counts of the experimental calves were statistically significantly lower than those of control calves at 2 hours post ingestion of colostrum and 3-7 days postcolostral. Conclusions: BNP can be induced in some calves by ingestion of colostrum from cows that have given birth to BNP calves

Kırk bin frank cihaz

Émile Richebourg'ün Saadet'te yayımlanan Kırk Bin Frank Cihaz adlı romanının ilk ve son tefrikalarıTefrikanın devamına rastlanmamış, tefrika yarım kalmıştır

Genome-wide identification and phenotypic characterization of seizure-associated copy number variations in 741,075 individuals

Copy number variants (CNV) are established risk factors for neurodevelopmental disorders with seizures or epilepsy. With the hypothesis that seizure disorders share genetic risk factors, we pooled CNV data from 10,590 individuals with seizure disorders, 16,109 individuals with clinically validated epilepsy, and 492,324 population controls and identified 25 genome-wide significant loci, 22 of which are novel for seizure disorders, such as deletions at 1p36.33, 1q44, 2p21-p16.3, 3q29, 8p23.3-p23.2, 9p24.3, 10q26.3, 15q11.2, 15q12-q13.1, 16p12.2, 17q21.31, duplications at 2q13, 9q34.3, 16p13.3, 17q12, 19p13.3, 20q13.33, and reciprocal CNVs at 16p11.2, and 22q11.21. Using genetic data from additional 248,751 individuals with 23 neuropsychiatric phenotypes, we explored the pleiotropy of these 25 loci. Finally, in a subset of individuals with epilepsy and detailed clinical data available, we performed phenome-wide association analyses between individual CNVs and clinical annotations categorized through the Human Phenotype Ontology (HPO). For six CNVs, we identified 19 significant associations with specific HPO terms and generated, for all CNVs, phenotype signatures across 17 clinical categories relevant for epileptologists. This is the most comprehensive investigation of CNVs in epilepsy and related seizure disorders, with potential implications for clinical practice

Charakterisierung nichtlinearer Signalverzerrung in faser-optischen Übertragungssystemen mit räumlichem Multiplex

Kerr-Effekt basierende Nichtlinearitäten stellen einen limitierenden Faktor für die Übertragungsleistung von faser-optischen Kommunikationssystemen mit räumlichen Multiplexverfahren (engl. Space Division Multiplexing (SDM), auch Mode Division Multiplexing (MDM)) da. Ziel dieser Arbeit ist eine fundierte Analyse von nichtlinearen Effekten, die in Übertragungssystemen mit Vielmoden Glasfasern, bei Verwendung von räumlichem Multiplex, auftreten können. Zunächst wurde eine analytische Abschätzung des Einflusses von intra- und intermodalen nichtlinearen Störungen berechnet, wobei eine idealisierte vielmodige Glasfaser angenommen wurde. Es wurde gezeigt, dass intermodale nichtlineare Störung von gleicher Größenordnung wie intramodal nichtlineare Störungen sein kann. Anhand eines exemplarischen Übertragungssystems wurde weiterhing gezeigt, dass eine vielmodige Glasfaser mit gleicher Leistungsdichte im Faserkern, höhere Übertragungsleistungen aufweist als eine einmodige Glasfaser. Das ist ein erstaunliches Ergebnis, da es zeigt, dass eine vielmodige Glasfaser nicht nur bei höherer absoluter Leistung sondern auch bei höherer Leistungsdichte betrieben werden kann als eine einmodige Glasfaser. Weiterhin wurde die maximale Übertragungskapazität einer vielmodigen Glasfaser die in etwa dem OM4 Standard entspricht ermittelt. Jede Mode dieser Glasfaser kann eine gleiche oder höhere Übertragungskapazität bieten als eine standard-einmodige Faser. Ein zweiter Schwerpunkt dieser Arbeit war die numerische Untersuchung von nichtlinearen Übertragungseffekten, die auftreten, wenn MDM in realistischeren Übertragungsszenarien eingesetzt wird. Dabei wurde zunächst der Einfluss von Differential Mode-Delay (DMD) management auf die Übertragungsqualität untersucht. Es wurde gezeigt, dass DMD management durch die Einführung einer Korrelation zwischen Signalen in unterschiedlichen Moden zu einer erhöhten nichtlinearen Störung führt. Zuletzt wurde der Einfluss der Kanal Granularität von Signalen mit Wellenlängen Multiplex auf die nichtlineare Signalausbreitung bestimmt. Dabei hat sich gezeigt, dass eine starke Fluktuation der Übertragungsleistung auftritt, wenn eine kleine Variation der differenziellen Gruppenlaufzeiten zwischen zwei Moden auftritt.Kerr-effect-based nonlinearities might be the limiting factor for the application of Mode-Division Multiplexed (MDM) transmission links. The goal of this study was to offer a thorough analysis of nonlinear effects that might occur in MDM systems with multi-mode fibers (MMF). An analytical estimation of the impact of intra- and intermodal nonlinear interaction in idealized MMF (no mode-dependent loss / no linear coupling) has been derived and validated by numerical simulations. It was observed that intermodal nonlinear interactions can occur in same order of magnitude as intramodal nonlinear interactions. It has been shown that each mode of an exemplary graded-index MMF based transmission system can outperform a single-mode fiber based systems with equal core-power densities when only considering Kerr-nonlinearities. This is a noteworthy result, as it shows that a multi-mode fiber cannot only be operated at higher absolute power than a single-mode fiber but also at higher power density. Furthermore, the nonlinear impairments in a standard MMF (similar to OM4-standard) were analyzed. It was found out that each fiber mode can achieve a better performance compared to a standard SMF. A second emphasis was the investigation of transmission effects that might arise when applying mode-division multiplexing in a more realistic system. Differential Mode-Delay (DMD) management was proposed to facilitate reduce the group-delay spread in order to facilitate Multiple-Input / Multiple Output (MIMO) that is required when considering linear mode coupling. It was shown in this work that DMD management can have a negative impact on the maximal achievable performance of each mode as a result of an increased signals correlation that has a negative impact on the nonlinear signal distortion. Finally, it was shown that the channel granularity in Wavelength-Division multiplexed (WDM) transmission links can lead to a strong performance fluctuation when the DMD varies in a range that might be within the tolerance of the fiber production process