Оптимизация условий для контроля качества наполнителя в металлических трубках

Проанализирована возможность с помощью цифровой радиографии контролировать качество наполнителя в детонирующем шнуре с целью обнаружения разноплотных включений, разрывов и других технологических нарушений. Проанализированы закономерности изменений интенсивности прошедшего потока квантов в геометрии узкого пучка. Определена энергия рентгеновского излучения, обеспечивающая максимальный перепад интенсивности прошедшего потока при изменении плотности наполнителя на +-30 %

Aberrant Activity of Histone–Lysine N-Methyltransferase 2 (KMT2) Complexes in Oncogenesis

KMT2 (histone-lysine N-methyltransferase subclass 2) complexes methylate lysine 4 on the histone H3 tail at gene promoters and gene enhancers and, thus, control the process of gene transcription. These complexes not only play an essential role in normal development but have also been described as involved in the aberrant growth of tissues. KMT2 mutations resulting from the rearrangements of the KMT2A (MLL1) gene at 11q23 are associated with pediatric mixed-lineage leukemias, and recent studies demonstrate that KMT2 genes are frequently mutated in many types of human cancers. Moreover, other components of the KMT2 complexes have been reported to contribute to oncogenesis. This review summarizes the recent advances in our knowledge of the role of KMT2 complexes in cell transformation. In addition, it discusses the therapeutic targeting of different components of the KMT2 complexes

Substrate-assisted catalysis by PARP10 limits its activity to mono-ADP-ribosylation

ADP-ribosylation controls many processes, including transcription, DNA repair, and bacterial toxicity. ADP-ribosyltransferases and poly-ADP-ribose polymerases (PARPs) catalyze mono- and poly-ADP-ribosylation, respectively, and depend on a highly conserved glutamate residue in the active center for catalysis. However, there is an apparent absence of this glutamate for the recently described PARP6-PARP16, raising questions about how these enzymes function. We find that PARP10, in contrast to PARP1, lacks the catalytic glutamate and has transferase rather than polymerase activity. Despite this fundamental difference, PARP10 also modifies acidic residues. Consequently, we propose an alternative catalytic mechanism for PARP10 compared to PARP1 in which the acidic target residue of the substrate functionally substitutes for the catalytic glutamate by using substrate-assisted catalysis to transfer ADP-ribose. This mechanism explains why the novel PARPs are unable to function as polymerases. This discovery will help to illuminate the different biological functions of mono- versus poly-ADP-ribosylation in cells