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Herein we describe the synthesis and photophysical and electrochemical characterization of pyrimidopteridine‐based photoredox catalysts. The pyrimidopteridines can be obtained from the corresponding N‐oxides through photo‐mediated oxygen atom transfer to a sacrificial acceptor molecule on gramscale. The presence of a triplet excited state was evidenced by means of transient absorption spectroscopy. Pyrimidopteridines are potent excited state oxidants with excited state reduction potentials exceeding +2.10 V vs. SCE in MeCN. The catalytic activity is illustrated in the photo‐mediated oxidative annulation of 2‐phenylbenzoic acid. [ABSTRACT FROM AUTHOR]

In cost–benefit analysis of lidar data acquisition, point density is often artificially reduced in order to examine how this affects the quality of derived products. However, the performance of the different density reduction methods has not yet been compared and their influence on the accuracy of the models and results has not been evaluated. A novel method for reducing the point density, termed Proportional per Cell (PpC), is presented and compared with the performance of three other reduction methods, examining their influence on the accuracy of lidar‐derived digital surface models using ISPRS reference data. The results indicate that the PpC method was better at conserving the characteristics of the original data. However, point density, sample type and slope had a greater influence than the reduction method used. [ABSTRACT FROM AUTHOR]

A series of thienoindolizine structural isomers have been synthesized in a one‐pot, two‐step procedure starting from easily accessible gem‐difluoroalkene functionalized bromothiophenes. The developed method gives easy access to a range of thienoindolizine products containing thieno[3,2‐g]‐, thieno[3,4‐g]‐ and thieno[2,3‐g]indolizine core structures. The described synthesis strategy consists of a base mediated, transition metal free nucleophilic substitution of fluorine atoms by nitrogen containing heterocycles followed by a Pd catalyzed intramolecular cyclization. A series of 22 final product examples has been obtained with yields ranging from 29 % to 95 %. UV/Vis absorption, fluorescence spectroscopy, fluorescence lifetime measurements and cyclic voltammetry were carried out with selected final products to evaluate structural effects on photophysical and electrochemical properties. (TD)DFT and NICS calculations were performed to provide insight into the electronic properties of the four core molecular structures. [ABSTRACT FROM AUTHOR]

Background Elucidating risk pathways for under-achieving at school can inform strategies to reduce the number of adolescents leaving school without passing grades in core subjects. Maternal depression can compromise the quality of parental care and is associated with multiple negative child outcomes. However, only a few small studies have investigated the association between perinatal maternal depression and poor academic achievement in adolescence. The pathways to explain the risks are also unclear. Method Prospective observational data from 5,801 parents and adolescents taking part in a large UK population cohort (Avon-Longitudinal-Study-of-Parents-and-Children) were used to test associations between maternal and paternal depression and anxiety in the perinatal period, executive function ( EF) at age 8, and academic achievement at the end of compulsory school at age 16. Results Adolescents of postnatally depressed mothers were 1.5 times (1.19, 1.94, p = .001) as likely as adolescents of nondepressed mothers to fail to achieve a 'pass' grade in math; antenatal anxiety was also an independent predictor of poor math. Disruption in different components of EF explained small but significant proportions of these associations: attentional control explained 16% (4%, 27%, p < .001) of the association with postnatal depression, and working memory explained 17% (13%, 30%, p = .003) of the association with antenatal anxiety. A similar pattern was seen for language grades, but associations were confounded by maternal education. There was no evidence that paternal factors were independently associated with impaired child EF or adolescent exams. Conclusion Maternal postnatal depression and antenatal anxiety are risk factors for adolescents underachieving in math. Preventing, identifying, and treating maternal mental health in the perinatal period could, therefore, potentially increase adolescents' academic achievement. Different aspects of EF partially mediated these associations. Further work is needed, but if these pathways are causal, improving EF could reduce underachievement in math. [ABSTRACT FROM AUTHOR]

Herein we report the photo‐ and electrochemical characterization of pyrimidopteridine N‐oxide‐based heterocycles. The potential of their application as organic photoredox catalysts is showcased in the photomediated contra‐thermodynamic E→Z isomerization of cinnamic acid derivatives and oxidative cyclization of 2‐phenyl benzoic acid to benzocoumarin using molecular oxygen as a mild oxidant. Furthermore, unprecedented intermolecular non‐covalent n–π‐hole interactions in solid state are discussed based on crystallographic and theoretical data. PyrimidopteridineN‐oxide‐based heterocycles exhibit excellent excited state reduction potentials paired with a suitable ground state reduction potential allowing for catalyst turnover with mild oxidants. The structural similarity between pyrimidopteridines and recently uncovered flavine N‐oxides may draw an important link between organic photoredox catalysis and chemical biology. [ABSTRACT FROM AUTHOR]

To assess the presence of genetic imbalances in patients with myeloproliferative neoplasms (MPNs), 38 patients with chronic eosinophilia were studied by array comparative genomic hybridization ( aCGH): seven had chronic myelogenous leukaemia (CML), BCR-ABL1 positive, nine patients had myeloproliferative neoplasia Ph− (MPN-Ph−), three had a myeloid neoplasm associated with a PDGFRA rearrangement, and the remaining two cases were Lymphoproliferative T neoplasms associated with eosinophilia. In addition, 17 patients had a secondary eosinophilia and were used as controls. Eosinophilic enrichment was carried out in all cases. Genomic imbalances were found in 76% of all MPN patients. Losses on 20q were the most frequent genetic abnormality in MPNs (32%), affected the three types of MPN studied. This study also found losses at 11q13.3 in 26% of patients with MPN-Ph− and in 19p13.11 in two of the three patients with an MPN associated with a PDGFRA rearrangement. In addition, 29% of patients with CML had losses on 8q24. In summary, aCGH revealed clonality in eosinophils in most MPNs, suggesting that it could be a useful technique for defining clonality in these diseases. The presence of genetic losses in new regions could provide new insights into the knowledge of these MPN associated with eosinophilia. [ABSTRACT FROM AUTHOR]