Characterization of Family IV UDG from Aeropyrum pernix and Its Application in Hot-Start PCR by Family B DNA Polymerase

Recombinant uracil-DNA glycosylase (UDG) from Aeropyrum pernix (A. pernix) was expressed in E. coli. The biochemical characteristics of A. pernix UDG (ApeUDG) were studied using oligonucleotides carrying a deoxyuracil (dU) base. The optimal temperature range and pH value for dU removal by ApeUDG were 55–65°C and pH 9.0, respectively. The removal of dU was inhibited by the divalent ions of Zn, Cu, Co, Ni, and Mn, as well as a high concentration of NaCl. The opposite base in the complementary strand affected the dU removal by ApeUDG as follows: U/C≈U/G>U/T≈U/AP≈U/->U/U≈U/I>U/A. The phosphorothioate around dU strongly inhibited dU removal by ApeUDG. Based on the above biochemical characteristics and the conservation of amino acid residues, ApeUDG was determined to belong to the IV UDG family. ApeUDG increased the yield of PCR by Pfu DNA polymerase via the removal of dU in amplified DNA. Using the dU-carrying oligonucleotide as an inhibitor and ApeUDG as an activator of Pfu DNA polymerase, the yield of undesired DNA fragments, such as primer-dimer, was significantly decreased, and the yield of the PCR target fragment was increased. This strategy, which aims to amplify the target gene with high specificity and yield, can be applied to all family B DNA polymerases

Biomechanical analysis of the acetabular buttress-plate: are complex acetabular fractures in the quadrilateral area stable after treatment with anterior construct plate-1/3 tube buttress plate fixation?

OBJECTIVE: The acetabular buttress-plate has been widely used in treating difficult cases with satisfying clinical results. However, the biomechanical properties of a postoperative acetabular fracture fixed by the buttress-plate are not clear. The purpose of this study was to evaluate the biomechanical properties of stability after the anterior tube buttress-plate fixation of complex acetabular fractures in the quadrilateral area. METHODS: A construct was proposed based on anterior construct plate - 1/3 tube buttress plate fixation for acetabular both-column fractures. Two groups of six formalin-preserved cadaveric pelvises were analyzed: (1) group A, the normal pelvis and (2) group B, anterior construct plate-1/3 tube buttress plate with quadrilateral area fixation. The displacements were measured, and cyclical loads were applied in both standing and sitting simulations. RESULTS: As the load was added, the displacements were

Effects of human capital, natural resource, urbanization, energy consumption on carbon emissions in the top ten emitter countries

The entire world is facing the problem of changing climate and distortion of environmental quality due to the rapid increase in carbon emissions. Therefore, this study was planned to examine the world’s top ten carbon emitter countries, and the time extent was from 1990 to 2019. We employed panel Kao cointegration and Pooled Mean Group (PMG) techniques to explore the effect of human development, natural resources, urbanization, and energy use on carbon emissions. The Kao cointegration test results reveal that endogenous variables in the study have robust cointegration with carbon emissions. The PMG techniques results suggest that natural resources, urbanization, and energy use positively impact carbon emission in the top ten carbon emitters countries. Conversely, human development has a negative impact on carbon emission in the selected sampled nations. Based on the study’s outcomes, the officials and policymakers of the sampled selected countries must set a policy to ensure environmental sustainability despite slowing down the process of economic development. More efforts are required to improve the human development index in the sampled selected economies. The overexploitation of natural resources should be revoked immediately to avoid more environmental damage. Further, green energy and urbanization should be introduced and publicized more effectively among society

6-Formyl-2-naphthyl cis-1,5,7-trimethyl-2,4-dioxo-3-aza­bicyclo­[3.3.1]nonane-7-carboxyl­ate

In the title compound, C23H23NO5, the C5N ring adopts an envelope conformation with a C atom as the flap, whilst the saturated C6 ring fused to it adopts a chair conformation. In the crystal, inversion dimers linked by pairs of N—H⋯O hydrogen bonds generate R 2 2(8) loops

Gravitational Corrections to the Energy-Levels of a Hydrogen Atom

The first order perturbations of the energy levels of a hydrogen atom in central internal gravitational field are investigated. The internal gravitational field is produced by the mass of the atomic nucleus. The energy shifts are calculated for the relativistic 1S, 2S, 2P, 3S, 3P, 3D, 4S and 4P levels with Schwarzschild metric. The calculated results show that the gravitational corrections are sensitive to the total angular momentum quantum number.Comment: 7 page

Di-μ-cyanido-1:2κ2 C:N,2:3κ2 N:C-hexa­cyanido-1κ3 C,3κ3 C-tetra­kis(1,10-phenanthroline)-1κ2 N,N′;2κ4 N,N′;3κ2 N,N′-1,3-dicobalt(III)-2-iron(II) tetra­hydrate

The hydro­thermal reaction of CoCl2·6H2O, 1,10-phenanthroline (phen) and K3[Fe(CN)6] in deionized water yielded the title cyanide-bridged trinuclear cluster, [Co2Fe(CN)8(C12H8N2)4]·4H2O or [{CoIII(phen)(CN)4}2{FeII(phen)2}]·4H2O, which contains two CoIII centers and one FeII center linked by cyanide bridges. The combination of coordinative bonds, O—H⋯N and O—H⋯O hydrogen bonds and π–π stacking inter­actions [centroid–centroid distance = 3.630 (2) Å] results in the stabilization of a supra­molecular structure. All uncoordinated water molecules are disordered. Thermogravimetric analysis reveals that the title complex loses the four crystal water mol­ecules at about 333 K, then the anhydrous phase loses no further mass up to about 573 K, above which decomposition occurs