Base Dependent DNA-carbon Nanotube Interactions: Activation Enthalpies and Assembly-disassembly Control

We quantify the base dependent interactions between single stranded DNA and single walled carbon nanotubes (SWNTs) in solution. DNA/SWNT hybrids hold the promise of applications ranging from nanoscale electronics and assembly of nanotube based materials, to drug delivery and DNA sequencing. These applications require control over the hybrid assembly and disassembly. Our analytical assay reveals the order of nucleobase binding strengths with SWNTs as G>C>A>T. Furthermore, time dependent fixed temperature experiments that probe the kinetics of the dissociation process provide values for the equilibrium constants and dissociation enthalpies that underlie the microscopic interactions. Quantifying the base dependency of hybrid stability shows how insight into the energetics of the component interactions facilitates control over hybrid assembly and disassembly.Engineering and Applied SciencesMolecular and Cellular BiologyPhysic

Molecular Complexation of Hederasaponin C with Cholesterol in Aqueous Isopropyl Alcohol

The 1:1 molecular complex of ivy triterpene glycoside hederasaponin C (HedC) with cholesterol (Chol) was obtained in aqueous isopropyl alcohol. The stability constant of (3.3 ± 0.7)∙106 (mol/L)–1 was calculated for the complex. The complexation was studied by UV- and ATR IR-Fourier spectroscopy, and method of isomolar series. The hydrogen bonds and hydrophobic interactions are formed in the molecular complex

Molecular Complexation of Hederasaponin C with Cholesterol in Aqueous Isopropyl Alcohol

The 1:1 molecular complex of ivy triterpene glycoside hederasaponin C (HedC) with cholesterol (Chol) was obtained in aqueous isopropyl alcohol. The stability constant of (3.3 ± 0.7)∙106 (mol/L)–1 was calculated for the complex. The complexation was studied by UV- and ATR IR-Fourier spectroscopy, and method of isomolar series. The hydrogen bonds and hydrophobic interactions are formed in the molecular complex

Clinical and laboratory indicators in pregnant women with preeclampsia

The objective of this study is to compare clinical and laboratory indicators in pregnant women with preeclampsia (PE) compared with women with physiological pregnancy. The study group included 209 women with physiological pregnancy and 250 pregnant women with PE. We studied coagulogram data, biochemical blood analysis, and the level of systolic and diastolic blood pressure before and during pregnanc

The study of the role of maternal and fetal risk factors in the development of placental insufficiency

The objectives were to study the role of maternal and fetal risk factors in the development of placental insufficiency (PI) and fetal growth retardation syndrome (FGRS

Critical analysis of the charge-state dependence of the energy loss of channeled ions

A critical analysis of channeled-ion energy-loss experiments is presented with the goal of commenting on the presence of the Barkas effect of Z31 corrections to the stopping power. Accurate charge-density values are obtained for silicon and used to evaluate Bloch and straggling effects in the data. The remaining contributions to the data show a clear Z31 dependence that can be explained with an electron-gas model for the Barkas effect.Physic

Dataset of allele, genotype and haplotype frequencies of four LIN28B gene polymorphisms analyzed for association with age at menarche in Russian women

In this paper, we present the allele, genotype and haplotype frequencies of 4 single nucleotide polymorphisms (SNPs) in LIN28B gene (rs4946651, rs7759938, rs314280, rs314276) in a sample of Russian women. These SNPs had been previously identified to be associated with age at menarche in genome-wide association studies (GWAS

Polarization Pendellösung and the Generation of Circularly Polarized X Rays with a Quarter-Wave Plate

A continuously tunable x-ray compensator that works in conjunction with synchrotron-radiation sources has been developed. The phenomena of polarization Pendellösung has been observed during its normal operation and the generation of circularly polarized x rays is verified through an observation of the magnetic Compton effect.Physic

State Transition Induced by Self-Steepening and Self Phase-Modulation

We present a rational solution for a mixed nonlinear Schr¨odinger (MNLS) equation. This solution has two free parameters a and b representing the contributions of self-steepening and self phasemodulation (SPM) of an associated physical system. It describes five soliton states: a paired bright-bright soliton, single soliton, a paired bright-grey soliton, a paired bright-black soliton, and a rogue wave state. We show that the transition among these five states is induced by self-steepening and SPM through tuning the values of a and b. This is a unique and potentially fundamentally important phenomenon in a physical system described by the MNLS equation

Method of drilling process control and experimental studies of resistance forces during bits drilling with PDC cutters

A rational, theoretically proved and empirically verified control system is a condition for optimal management of the drilling process in compliance with the criteria for minimizing the cost of time and material resources. A new generation of rock-cutting tools using PDC cutters (polycrystalline diamante cutters), which are extremely effective when drilling wells for various purposes in medium-hard rocks, dictates the need to develop methods and criteria for optimal control of the drilling process using this tool. The paper presents an analysis of the force interaction between rock-cutting elements, face rock, and drilling mud saturated with slam, highlights the influencing factors and provides dependencies for determining the parameters of rock failure. Empirical verification of the theoretical propositions was carried out based on the data analysis from experimental bit drilling of marble with PDC cutters with a diameter of 76.2 mm, processed using the method of full factor experiment to obtain mathematical models of factors and their graphical interpretation. The method of controlling the drilling process based on the optimal ratio of the tool rotation frequency, axial weight and deepening per one turnover is considered, which allows determining the rock failure mode at the well bottom by indirect signs and choose the optimal values of the drilling mode parameters that correspond to the most optimal conditions in terms of achieving the maximum mechanical drilling speed in conjunction with the rational mode of rock-cutting tool operation. A scheme is presented that contains possible variants of the bit run mode and ways to recognize them by the ratio of the deepening per turnover and the rotation frequency of the rock-cutting tool