Zur Kenntnis der Azulene, X. Über Azulen-enamine und deren Umwandlung in tricyclische Pentalen- und Heptalen-Derivate

Die alkalische Hydrolyse von [4.6.8-Trimethyl-azulyl-(1)]-N.N-dialkyl-ketimmonium-Salzen, die leicht aus Azulenen und Carbonsäure-dialkylamiden in Gegenwart von Phosphoroxychlorid entstehen, führt zu stabilen Azulen-enaminen. Diese reagieren mit Alkylierungs- und Acylierungsmitteln unter Bildung tricyclischer Pentalen- und Heptalenderivate, deren Reaktionen Rückschlüsse auf ihre Feinstruktur erlauben

Interaction between Sox proteins of two physiologically distinct bacteria and a new protein involved in thiosulfate oxidation

AbstractOrganisms using the thiosulfate-oxidizing Sox enzyme system fall into two groups: group 1 forms sulfur globules as intermediates (Allochromatium vinosum), group 2 does not (Paracoccus pantotrophus). While several components of their Sox systems are quite similar, i.e. the proteins SoxXA, SoxYZ and SoxB, they differ by Sox(CD)2 which is absent in sulfur globule-forming organisms. Still, the respective enzymes are partly exchangeable in vitro: P. pantotrophus Sox enzymes work productively with A. vinosum SoxYZ whereas A. vinosum SoxB does not cooperate with the P. pantotrophus enzymes. Furthermore, A. vinosum SoxL, a rhodanese-like protein encoded immediately downstream of soxXAK, appears to play an important role in recycling SoxYZ as it increases thiosulfate depletion velocity in vitro without increasing the electron yield

Probabilistic Routing for On-Street Parking Search

An estimated 30% of urban traffic is caused by search for parking spots [Shoup, 2005]. Suggesting routes along highly probable parking spots could reduce traffic. In this paper, we formalize parking search as a probabilistic problem on a road graph and show that it is NP-complete. We explore heuristics that optimize for the driving duration and the walking distance to the destination. Routes are constrained to reach a certain probability threshold of finding a spot. Empirically estimated probabilities of successful parking attempts are provided by TomTom on a per-street basis. We release these probabilities as a dataset of about 80,000 roads covering the Berlin area. This allows to evaluate parking search algorithms on a real road network with realistic probabilities for the first time. However, for many other areas, parking probabilities are not openly available. Because they are effortful to collect, we propose an algorithm that relies on conventional road attributes only. Our experiments show that this algorithm comes close to the baseline by a factor of 1.3 in our cost measure. This leads to the conclusion that conventional road attributes may be sufficient to compute reasonably good parking search routes

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

Zur Kenntnis der Azulene, X. Über Azulen-enamine und deren Umwandlung in tricyclische Pentalen- und Heptalen-Derivate

Die alkalische Hydrolyse von [4.6.8-Trimethyl-azulyl-(1)]-N.N-dialkyl-ketimmonium-Salzen, die leicht aus Azulenen und Carbonsäure-dialkylamiden in Gegenwart von Phosphoroxychlorid entstehen, führt zu stabilen Azulen-enaminen. Diese reagieren mit Alkylierungs- und Acylierungsmitteln unter Bildung tricyclischer Pentalen- und Heptalenderivate, deren Reaktionen Rückschlüsse auf ihre Feinstruktur erlauben

Kinetic analysis of the abnormal fluorimetric titration behaviour of naphthylamines

The fluorimetric titration behaviour of naphthylamines is abnormal in that the sum of the reduced quantum yields of conjugated acid and base passes through a minimum. Based on fluorescence quantum yield and lifetime measurements, we explain this behaviour by two independent mechanisms: A diabatic quenching of the excited base by protons and a decrease of the excited cation's protolytic dissociation in the hyperacidic region. Though apparently independent processes, their rate constants can be shown to be related to each other by a quasi-thermodynamical equation

Inhibition of Voriconazole Metabolism by Chloramphenicol in an Adolescent with Central Nervous System Aspergillosis▿

For an adolescent with bacterial meningitis and subsequent cerebral aspergillosis, intravenous voriconazole dose requirements substantially decreased during coadministration with intravenous chloramphenicol and considerably rose after discontinuation of the antibiotic. In agreement with in vitro evidence, these data suggest that chloramphenicol is a rather significant inhibitor of hepatic CYP3A4 and/or CYP2C19