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This paper presents a theoretical criterion and approach for determining the relationship between the critical hydrogen concentration for hydrogen-induced cracking (HIC) initiation and the type and size of non-metallic inclusions. We used plate-like MnS and sphere-like Al2O3as representative inclusions for in-depth analyses. Our results indicate that decreasing inclusion size increases the hydrogen concentration required for HIC initiation, particularly in the range of small inclusion sizes. Al2O3exhibits a higher susceptibility to HIC than MnS. Each type of inclusion has a specific hydrogen concentration below which crack initiation cannot begin. The critical concentration for HIC initiation in the entire steel corresponds to the lowest value among these concentrations. This study provides a quantitative and comprehensive solution to this issue.

High-energy particle irradiation-induced crystallization technology presents remarkable potential for precise nanostructure design. However, the fundamental mechanism behind this process remains a long-standing unsolved puzzle. In this paper, we used a high-energy electron beam as the irradiation source and amorphous Fe85B15alloy as a model system to investigate the behavior of irradiation-induced structural changes. Our experimental results show that the nucleation barrier in irradiation-induced crystallization ranges from 0.5 to 0.8 eV, depending on the temperature, much smaller than that observed in thermal-induced crystallization. Additionally, the nucleation entropy observed is −1.60 × 10−3 eV/K, and the entropic contribution to the nucleation barrier dominates over the enthalpic contribution. This paper provides compelling experimental evidence demonstrating that nucleation in irradiation-induced crystallization is not a thermally activated effect; instead, it is a process in which the amorphous state progresses through a series of intermediate short-range ordering configurations toward a crystalline state with the assistance of irradiation-induced atomic rearrangement.

Sensitive nature of organic-inorganic hybrid perovskite material provides an opportunity to turn its electrochemical property. Herein, the conversion process from three-dimensional (3D) CH3NH3PbI3(MAPbI3) microcubes to one-dimensional (1D) nanorod aggregates was reported by NH3post-treatment for 30 min, which enhanced the carrier mobility (36.91 cm2/V) and Li-ion diffusion coefficient (5.26 × 10−9cm2s−1) and narrowed the optical band gap (1.385 eV) of MAPbI3nanorod aggregates. The morphology evolution of 3D MAPbI3crystals and 1D MAPbI3nanorod rebuilding mechanism induced by NH3have been investigated and proposed. In addition, compared with samples without NH3treatment, 1D nanorod aggregates exhibited the improved electrochemical performances including capacity (from 53 mA h g−1to 243 mA h g−1) and cycle stability (132 mA h g−1, 300th cycle) which are ascribed to the improved electronic properties and special 1D microstructure.

Theoretically, controlling redox potential to a relatively low value and inhibiting jarosite formation on the chalcopyrite surface would be an effective strategy to accelerate the bioleaching of chalcopyrite. In this work, using limonite as seed crystals, the effects of the goethite precipitation process on the bioleaching of chalcopyrite were studied for the first time. The bioleaching results showed that the addition of limonite controlled the redox potential in an appropriate range and promoted chalcopyrite dissolution through the removal of ferric (Fe3+) ions. X-ray diffraction and scanning electron microscope analyses indicate that limonite significantly induced the goethite precipitation process and inhibited the production of jarosite. We conclude that promoting the goethite precipitation process with limonite is an effective strategy in accelerating the bioleaching process of chalcopyrite.

Carbon quantum dots (CQDs) are emerging carbonaceous photocatalysts, but the efficiency is unsatisfactory due to a narrow visible-light response and high electron-hole recombination. In this work, we fine-tuned the surface chemistry of CQDs via selectively substituting surface carbonyl group (C=O) with phenylhydrazine (PH). Such a modification optimized the conductivity and band structures of the derived products (CQDs-PH) with improved light absorption and separation of photogenerated electron-hole pairs, leading to boosted generation of reactive oxygen species (ROS) via peroxymonosulfate (PMS) activation. In addition, the primary ROS are identified as superoxide radicals (O2•−) and holes, whereas O2•−are produced from CQDs-activated PMS rather than from dissolved oxygen. Theoretical calculations illustrate that the electrons and holes on CQDs are spatially separated due to the spontaneous surface polarization induced by PH functionalization. This study provides a feasible approach to enhancing the photocatalytic activity of CQDs for sustainable water decontamination.

Study design:Descriptive study.Objectives:The goal of this study was to determine the effects of spinal cord injury (SCI) on aspects of the focal adhesion kinase (FAK) signaling pathway 56 days post injury in rat gastrocnemius.Setting:This study was conducted in Bronx, NY, USA.Methods:Three-month-old male Wistar rats were exposed to either a sham surgery (n=10) or complete T4 spinal cord transection (n=10). Rats were killed 56 days following surgery and the muscle was collected. Following homogenization, proteins of the FAK pathway were analyzed by western immunoblotting or reverse transcription-qPCR. In addition, cellular markers for proteins that target the degradation of FAK were investigated.Results:SCI resulted in significantly lower levels of total and phosphorylated FAK, cSrc and p70S6k, and a trend for increased FRNK protein expression. SCI did not change levels of the α7 or β1 integrin subunits, total or phosphorylated ERK1/2, phosphorylated Akt and TSC2 or total p70S6k. SCI resulted in a greater expression of total Akt. mRNA expression of FAK and the α7 or β1 integrins remained unchanged between sham and SCI groups. Caspase-3/7 activity and Trim72 mRNA and protein expression remained unchanged following SCI.Conclusion:SCI results in diminished FAK signaling and is independent of ERK1/2 and Akt. SCI has no effect on mRNA levels for genes encoding components of the focal adhesion 56 days after injury.

Hypoxic microenvironment is a powerful driving force for the invasion and metastasis of hepatocellular carcinoma (HCC). Hypoxia-inducible factor 1α (HIF-1α), as a crucial regulator of transcriptional responses to hypoxia, induces the expression of multiple target genes involved in different steps of HCC metastatic process. It is critical to find target genes associated with metastasis under hypoxia for shedding new light on molecular mechanism of HCC metastasis. In this study, we uncovered that hypoxia could induce the upregulation of Rab11-family interacting protein 4 (Rab11-FIP4) and activation of Rab11-FIP4 promoter by HIF-1α. The overexpression of Rab11-FIP4 significantly enhanced the mobility and invasiveness of HCC cells in vitro, also contributed to distant lung metastasis in vivo, whereas silencing of Rab11-FIP4 decreased the ability of migration and invasion in HCC cells in vitroand suppressed lung metastasis in vivo. Rab11-FIP4 facilitated HCC metastasis through the phosphorylation of PRAS40, which was regulated by mTOR. Furthermore, the expression level of Rab11-FIP4 was significantly increased in HCC tissues and high expression of Rab11-FIP4 was closely correlated with vascular invasion and poor prognosis in HCC patients. A markedly positive correlation between the expression of Rab11-FIP4 and HIF-1α was observed in HCC tissues and combination of Rab11-FIP4 and HIF-1α was a more valuable predictor of poor prognosis for HCC patients. In conclusion, Rab11-FIP4 is a target gene of HIF-1α and has a pro-metastatic role in HCC, suggesting that Rab11-FIP4 may be a promising candidate target for HCC treatment.

In this paper, the authors analysed the impact of machine breakdowns in job shop scheduling problem with parallel machines. A mathematical model with the objective of minimizing the weighted value of makespan and early due date was established. An improved ant colony dynamic scheduling algorithm combined with elite strategy and max-min ant mechanism was designed. Simulation experiments were designed and numerical results verified the superiority of the proposed approach.

The introduction of antibiotics to treat bacterial infections either by killing or blocking their growth has been accompanied by the development of resistance mechanism that allows the bacteria to survive and proliferate. In particular the successive series of - lactams have selected several generations of -lactamases including ESBLs, AmpC -lactamases, KPC carbapenamases in Enterobacteriaceae, the metallo -lactamases VIMs and IMPs, and very recently the threatening NDM-1 that confers resistance to virtually any clinically used antibiotic. The increasing use of carbapenems due to the spread of resistance to other existing antibacterial agents has facilitated the spread of resistance, especially in Acinetobacter spp. due to OXA- and metallo-carbapenemases. The pharmaceutical industry, that abandoned this field at the end of the nineties, is now trying to recover by developing some novel -lactam antibiotics and novel - lactamase-inhibitors, the latter to be used in combination with new as well as seasoned -lactam antibiotics. This article provides a survey of patent and scientific literature for -lactamase inhibitors discovered in the period 2006-2010.

This study investigated the relationship between peripheral blood B lymphocytes, regulatory T-cells and T lymphocyte subsets, the distribution of B lymphocytes in the kidney, and the pathogenesis of idiopathic membranous nephropathy (IMN). Lymphocyte subsets were measured using flow cytometry in 66 patients with clinically-confirmed IMN and in 40 healthy control subjects. Compared with healthy subjects, the number of peripheral blood B lymphocytes was significantly increased in IMN patients and that of regulatory T-cells was significantly decreased, accompanied by an increased CD4+/CD8+T-cell ratio. There was no relationship between the number of peripheral blood B lymphocytes and markers of kidney function. Although the number of infiltrating B lymphocytes in the kidney of IMN patients was higher, there was no relationship with the number of peripheral blood B lymphocytes. In conclusion, there was no relationship between peripheral blood B lymphocytes and disease activity, suggesting that peripheral blood B lymphocytes are not a biomarker of disease activity and therapeutic efficacy in IMN.

In this paper, optimization of the local cam profile of a valve train modelled by a parameterized Bezier curve is described. Dynamic responses of the valve train are simulated through its multi-body system dynamics model built using ADAMS software. The kriging method is used to build the surrogate model, which presents the relationship between dynamic responses resulting from the multi-body system dynamics simulation and the parameters of the local Bezier profile. The local cam profile is optimized through a generic algorithm, such that the acceleration peak at the valve open phase is reduced significantly.

Increasing nitrogen (N) and phosphorus (P) inputs have greatly contributed to the increasing food production in China during the last decades, but have also increased N and P losses to the environment. The pathways and magnitude of these losses are not well quantified. Here, we report on N and P use efficiencies and losses at a national scale in 2005, using the model NUFER (NUtrient flows in Food chains, Environment and Resources use). Total amount of “new” N imported to the food chain was 48.8 Tg in 2005. Only 4.4.Tg reached households as food. Average N use efficiencies in crop production, animal production, and the whole food chain were 26, 11, and 9%, respectively. Most of the imported N was lost to the environment, that is, 23 Tg N to atmosphere, as ammonia (57%), nitrous oxide (2%), dinitrogen (33%), and nitrogen oxides (8%), and 20 Tg to waters. The total P input into the food chain was 7.8 Tg. The average P use efficiencies in crop production, animal production, and the whole food chain were 36, 5, and 7%, respectively. This is the first comprehensive overview of N and P balances, losses, and use efficiencies of the food chain in China. It shows that the N and P costs of food are high (for N 11 kg kg−1, for P 13 kg kg−1). Key measures for lowering the N and P costs of food production are (i) increasing crop and animal production, (ii) balanced fertilization, and (iii) improved manure management.

The PLATeau Observatory (PLATO) is an automated self-powered astrophysical observatory that was deployed to Dome A, the highest point on the Antarctic plateau, in 2008 January. PLATO consists of a suite of site-testing instruments designed to quantify the benefits of the Dome A site for astronomy, and science instruments designed to take advantage of the unique observing conditions. Instruments include CSTAR, an array of optical telescopes for transient astronomy; Gattini, an instrument to measure the optical sky brightness and cloud cover statistics; DASLE, an experiment to measure the statistics of the meteorological conditions within the near-surface layer; Pre-HEAT, a submillimeter tipping radiometer measuring the atmospheric transmission and water vapor content and performing spectral line imaging of the Galactic plane; and Snodar, an acoustic radar designed to measure turbulence within the near-surface layer. PLATO has run completely unattended and collected data throughout the winter 2008 season. Here we present a detailed description of the PLATO instrument suite and preliminary results obtained from the first season of operation.

A high throughput screen was conducted to identify inhibitors of the RNA-dependent RNA polymerase (RdRp) of HCV. One of the classes identified was related to toxoflavin, a naturally occurring antibiotic. These compounds were potent inhibitors of HCV RdRp, with optimization of the initial hits giving compounds with half-maximal inhibition at 200 nM. However, binding studies indicated that a physical interaction with RdRp was too weak to be detected. Inhibition was dependent on reducing agent, implicating the flavin core as essential to the inhibitory properties of these compounds. The accumulation of the inhibitory species occurred over a time span of 1 to 2 hours, the period of time required for oxidation of a 10 to 100-fold excess of DTT by the flavin. These results indicate that the inhibitory species is likely to be a chemically reactive species resulting from the interaction of the flavin and DTT. Human RNA polymerase II was also sensitive to inhibition by these toxoflavin-like compounds. While this class of inhibitors has generated interest as antibacterial, antifungal and antitumor agents, their use has been limited by toxicity. These results provide a potential mechanism to explain the toxicity of these compounds.

Self-assembling of metallic nanoparticles to form well-defined nanostructured structures is a field that has been receiving considerable research interest in recent years. In this field, DNA is a commonly used linker molecule to direct the assembly of the nanoscale building blocks because of its unique recognition capabilities, mechanical rigidity, and physicochemical stability. This study reported our novel approach to generate gold nanoparticle-DNA conjugates bearing specially designed DNA linker molecules that can be used as building blocks to construct nanoassemblies with precisely controlled structure or as nanoprobes for quantitative DNA sequence detection analysis. In our approach, gold nanoparticle-DNA conjugates bearing a specific number of long double-stranded DNA strands were prepared by gel electrophoresis. A restriction endonuclease enzyme was then used to manipulate the length of the nanoparticle-bound DNA. This enzymatic cleavage was confirmed by gel electrophoresis, and digestion efficiency of 90% or more was achieved. With this approach, nanoparticle conjugates bearing a specific number of strands of short DNA with less than 20-base can be achieved.

A potassium-selective fluorescent BODIPY-linked azacrown ether chemosensor has been synthesized using novel substitution reactions of 3,5-dichloroBODIPY. The indicator absorbs and emits light in the visible wavelength range. The dissociation constant Kd for the complex between K⁺ and the probe is 0.5 mM in acetonitrile. Quantum chemical calculations show that the experimental hypsochromic shifts in absorption and fluorescence upon potassium binding are due to complexation, which induces a large conformational change of the sensor.

Permeability-frequency spectra of Nanoperm alloys were studied by using an impedance analyzer in the temperature range from 80 K to 290 K. It is shown that with decreasing temperature, the initial permeability (μi) decreases and the relaxation frequency (f0) increases, and the temperature dependence of μif0 has a minimum at 140 K. These results indicate that the temperature fall reduces the domain thickness, strengthens the domain wall pinning and enhances the eddy-current loss in high frequency ranges. Relative to domain thickness and resistivity, the effects of domain wall pinning strength on μi and f0 are dominant. Above 140 K, the effect of resistivity decrease on μif0 is more important, compared with domain thickness, whereas below 140 K, the case is just inverse. The temperature is an important factor affecting the dynamic magnetic properties of Nanoperm alloys. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Human estrogen receptor-positive breast cancer cells typically display elevated levels of Myc protein due to overexpression of MYC mRNA, and elevated insulin-like growth factor 1 receptor (IGF1R) due to overexpression of IGF1R mRNA. We hypothesized that scintigraphic detection of MYC peptide nucleic acid (PNA) probes with an IGF1 peptide loop on the C-terminus, and a [^99mTc]chelator peptide on the N-terminus, could measure levels of MYC mRNA noninvasively in human IGF1R-overexpressing MCF7 breast cancer xenografts in nude mice. We prepared the chelator-MYC PNA-IGF1 peptide, as well as a 4-nt mismatch PNA control, by solid-phase synthesis. We imaged MCF7 xenografts scintigraphically and measured the distribution of [^99mTc]probes by scintillation counting of dissected tissues. MCF7 xenografts in nude mice were visualized at 4 and 24 h after tail vein administration of the [^99mTc]PNA probe specific for MYC mRNA, but not with the mismatch control. The [^99mTc]probes distributed normally to the kidneys, livers, tumors, and other tissues. Molecular imaging of oncogene mRNAs in solid tumors with radiolabel-PNA−peptide chimeras might provide additional genetic characterization of preinvasive and invasive breast cancers.

Nanocomposite CoPt:C films were fabricated by sputtering Co, Pt and C onto water-cooled Si(100) substrates with subsequent annealing. The microstructure and the magnetic properties of these CoPt:C films were investigated as a function of Pt concentration. It was found that the orientations of CoPt grains and the magnetic properties are related strongly to the Pt content. Perpendicular anisotropy was observed in the films with high Pt content. By changing Pt concentrations, films with adjustable coercivity, a grain size less than 10 nm and strong perpendicular magnetic anisotropy were obtained. The crystal lattice structure and the intergranular interactions were proposed to be key factors in the magnetic properties of the CoPt:C films. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Effects of applied dc transverse and longitudinal magnetic fields on the dynamic magnetization of Nanoperm alloys are studied by using permeability spectroscopy. It is observed that the permeability-frequency spectra of Nanoperm alloys are very sensitive to the dc transverse magnetic fields. The applied dc transverse magnetic fields may strengthen the domain wall pinning, making the permeability decrease and the relaxation frequency move toward higher frequency. The dc longitudinal magnetic fields have no significant influence on the permeability-frequency spectra. The contribution to initial permeability only results from the bulging of the domain walls parallel to the applied ac magnetic field. The effect of the Earth's magnetic field on the dynamic magnetic properties of Nanoperm alloys must be considered in actual application. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Extraction of p-aminophenol by trialkylamine, trialkylphosphine oxide, di(2-ethylhexyl)phosphoric acid, and the mixed solvent of trialkylamine + trialkylphosphine oxide in heptane was studied under initial pH values ranging from 3 to 10. Trialkylamine and trialkylphosphine oxide extractants extracted the neutral form of p-aminophenol. Di(2-ethylhexyl)phosphoric acid extracted both neutral and positive forms of p-aminophenol. When the initial pH value was between pKa1 and pKa2, a maximum distribution coefficient occurred. This pH dependence can be explained by the variation of the molar fraction of neutral p-aminophenol with pH value. The mixed solvent consisting of trialkylamine + trialkylphosphine oxide had a higher distribution coefficient than the sum of those of trialkylamine and trialkylphosphine oxide; that is, there was a synergistic effect when extracting p-aminophenol with the mixed solvent.

Liquid−liquid equilibria for aqueous solutions of carboxylic acids, namely formic, acetic, propionic, butyric, valeric, monochloroacetic, dichloroacetic, trichloroacetic, glyoxylic, glycolic, and lactic acids, with trioctylamine (TOA) in various diluents, including 1-octanol, chloroform, methyl isobutyl ketone (MIBK), tetrachloromethane, and hexane, were determined at various TOA concentrations. The loading of TOA for a given carboxylic acid depends on the nature of the solute; the hydrophobicity and pKa of the acid; and the nature of solvent, diluent type, and TOA concentration, which can be expressed by the specific basicity of TOA (pK‘a,B), and increases with increasing acidity and hydrophobicity of the acid. The strength of solvation of the complex by the diluent for the acids studied decreases in the order 1-octanol  chloroform > MIBK > tetrachloromethane > hexane. An equilibrium model is presented that employs the mass action law and is used to determine model parameters and apparent extraction equilibrium constants (K11). The apparent extraction equilibrium constants depend on the hydrophobicity and acidity of the carboxylic acid, as well as the specific basicity of TOA, and the quantitative correlation of log K11 is obtained using log P, pKa, and pK‘a,B.

Liquid−liquid equilibria for aqueous solutions of acetic acid derivatives, formic, monochloroacetic, dichloroacetic, and trichloroacetic acids, with trioctylamine in various diluents, 1-octanol, chloroform, hexane, and tetrachloromethane, were determined at 298 K. The loading of trioctylamine was calculated, and the extraction behavior was discussed on the basis of the loading. The degrees of extraction of these medium-strong carboxylic acids with trioctylamine are in the order 1-octanol ≥ chloroform > tetrachloromethane > hexane at Zexp < 1. The strong acid provides a larger loading of trioctylamine than the weak acid; that is, the consequence is that trichloroacetic acid > dichloroacetic acid > monochloroacetic acid > formic acid > acetic acid, and this result depends on both the acidity and hydrophobicity of the acid.

Imaging oncogene mRNA in tumours would provide a powerful tool for the early detection of occult malignant lesions. The goal was to prepare a chimera consisting of a dodecamer antisense peptide nucleic acid PNA specific for cMYConcogene overexpressed in human breast cancer cells and a chelating moiety that facilitates quantitative radiolabelling with 99mTc and evaluate it for hybridization and tissue distribution in laboratory animals. The pentapeptide chelatorPNA dodecamer specific for cMYCmRNA was extended from a solid support by 9fluorenylmethyloxycarbonyl Fmoc coupling. Similarly, a chelatorPNA chimera with four central mismatches was also prepared which served as a control. The chimeras were purified, characterized and evaluated for hybridization to cMYCmRNA by fluorescent, realtime polymerase chain reaction RTPCR. The chimeras were labelled with 99mTc and their tissue distribution was examined in athymic nude mice bearing experimental human breast tumours. 99mTc radiolabelling was quantitative and presented a single peak in reversed phase liquid chromatography. Fluorescent realtime polymerase chain reactions using primer and fluorescent probe sets previously calculated for cMYCmRNA demonstrated inhibition of reverse transcription by the cMYCspecific chimera as compared to that of the control. Tissue distribution studies of antisense and mismatch chimeras at 4 h and 24 h after administration displayed modest accumulation in the liver, and appreciable levels in tumours. These observations suggest that 99mTcpeptidePNA probes might be useful for imaging gene expression in tumours, and the approach is worthy of further investigation.

Extraction of glycolic acid and glyoxylic acid from aqueous solution by trialkylphosphine oxide in methyl isobutyl ketone and trioctylamine in 1-octanol was studied under various extractant and acid concentrations. Glycolic acid can be extracted into the organic phase better by trialkylphosphine oxide than glyoxylic acid, whereas glyoxylic acid can be extracted into the organic phase better by trioctylamine than glycolic acid. Trialkylphosphine oxide could be used to remove glycolic acid from the mixture of glycolic acid and glyoxylic acid. A mathematical model was developed to describe the above liquid−liquid equilibrium. The reactive extraction mechanism of glycolic and glyoxylic acids with trialkylphosphine oxide and trioctylamine is also discussed.

Whereas ATP consumption increases with neural activity and is buffered by phosphocreatine (PCr), it is not known whether PCr synthesis by ubiquitous mitochondrial creatine kinase (uMtCK) supports energy metabolism in all neurons. To explore the possibility that uMtCK expression in neurons is modulated by activity and during development, we used immunocytochemistry to detect uMtCK-containing mitochondria. In the adult brain, subsets of neurons including layer Va pyramidal cells, most thalamic nuclei, cerebellar Purkinje cells, olfactory mitral cells and hippocampal interneurons strongly express uMtCK. uMtCK is transiently expressed by a larger group of neurons at birth. Neurons in all cortical layers express uMtCK at birth (P0), but uMtCK is restricted to layer Va by P12. uMtCK is detected in cerebellar Purkinje cells at birth, but localization to dendrites is only observed after P5 and is maximal on P14. Hippocampal CA1 and CA3 pyramidal neurons contain uMtCK-positive mitochondria at birth, but this pattern becomes progressively restricted to interneurons. Seizures induced uMtCK expression in cortical layers II–III and CA1 pyramidal neurons. In the cortex, but not in CA1, blockade of seizures prevented the induction of uMtCK. These findings support the concept that uMtCK expression in neurons is (1) developmentally regulated in post-natal life, (2) constitutively restricted in the adult brain, and (3) regulated by activity in the cortex and hippocampus. This implies that mitochondrial synthesis of PCr is restricted to those neurons that express uMtCK and may contribute to protect these cells during periods of increased energy demands.

Based on a systematic investigation of the literature, p-aminobenzenesulfonic acid was selected as a typical solute to be separated from the dilute solution. An aliphatic, straight-chain amine, Alamine 336, and a chlorinated quaternary ammonium salt, Aliquat 336, were used as extractants. The effects of pH value, concentration of the extractant, type of diluents, and salt on the distribution coefficient, D, on extraction equilibrium were studied in the experiments. The results showed that protic, polar diluents were favorable for extracting p-aminobenzenesulfonic acid when Alamine 336 was used as the extractant, while the inert diluent was favorable when Aliquat 336 was used as the extractant. Salt existing in the aqueous phase apparently reduced the D of p-aminobenzenesulfonic acid. Meanwhile, the proton transfer and ion exchange in the extraction process were discussed. The extraction equilibria for both amines were described using the mass action law, and the results showed that the calculating data agree with the experimental data well. Further, the extraction behavior for other aminobenzenesulfonic, H, and DSD acids was investigated with Alamine 336 as the extractant in a wide pH region. The results showed that the extractant used for aminobenzenesulfonic acid depends on the requirement of the number of equilibrium stages and extraction yield.

[99mTc]PNA-peptide conjugates capable of binding to IGF1 receptors will be synthesized. Specificity of their uptake and hybridization to mRNA in normal epithelial human cells compared to human breast cancer cells will be studied.

Liquid−liquid equilibria of aqueous solutions of acetic, propionic, butyric, and valeric acids with trioctylamine in various diluents, 1-octanol, chloroform, methyl isobutyl ketone, and tetrachloromethane, were determined at 298 K. An expression of the extraction equilibrium is derived, and the apparent extraction equilibrium constants (K11) are evaluated. The predicted loading of trioctylamine agrees well with the experimental values. The relationship between the K11 and the hydrophobicities of the acids is discussed.

Cells of vertebrates remove DNA double-strand breaks (DSBs) from their genome predominantly utilizing a fast, DNA-PKcs-dependent form of non-homologous end joining (D-NHEJ). Mutants with inactive DNA-PKcs remove the majority of DNA DSBs utilizing a slow, DNA-PKcs-independent pathway that does not utilize genes of the RAD52 epistasis group, is error-prone and can therefore be classified as a form of NHEJ (termed basic or B-NHEJ). We studied the role of DNA ligase IV in these pathways of NHEJ. Although biochemical studies show physical and functional interactions between the DNA-PKcs/Ku and the DNA ligase IV/Xrcc4 complexes suggesting operation within the same pathway, genetic evidence to support this notion is lacking in mammalian cells. Primary human fibroblasts (180BR) with an inactivating mutation in DNA ligase IV, rejoined DNA DSBs predominantly with slow kinetics similar to those observed in cells deficient in DNA-PKcs, or in wild-type cells treated with wortmannin to inactivate DNA-PK. Treatment of 180BR cells with wortmannin had only a small effect on DNA DSB rejoining and no effect on cell radiosensitivity to killing although it sensitized control cells to 180BR levels. This is consistent with DNA ligase IV functioning as a component of the D-NHEJ, and demonstrates the unperturbed operation of the DNA-PKcs-independent pathway (B-NHEJ) at significantly reduced levels of DNA ligase IV. In vitro, extracts of 180BR cells supported end joining of restriction endonuclease-digested plasmid to the same degree as extracts of control cells when tested at 10 mM Mg(2+). At 0.5 mM Mg(2+), where only DNA ligase IV is expected to retain activity, low levels of end joining ( approximately 10% of 10 mM) were seen in the control but there was no detectable activity in 180BR cells. Antibodies raised against DNA ligase IV did not measurably inhibit end joining at 10 mM Mg(2+) in either cell line. Thus, in contrast to the situation in vivo, end joining in vitro is dominated by pathways with properties similar to B-NHEJ that do not display a strong dependence on DNA ligase IV, with D-NHEJ retaining only a limited contribution. The implications of these observations to studies of NHEJ in vivo and in vitro are discussed.

To assess the functional significance of adenosine salvage in plants, the cDNAs and genes encoding two isoforms of adenosine kinase (ADK) were isolated from Arabidopsis. The ADK1- and ADK2-coding sequences are very similar, sharing 92% and 89% amino acid and nucleotide identity, respectively. Each cDNA was overexpressed in Escherichia coli, and the catalytic activity of each isoform was determined. Both ADKs had similar catalytic properties with a K(m) and V(max)/K(m) for adenosine of 0.3 to 0.5 microM and 5.4 to 22 L min(-1) mg(-1) protein, respectively. The K(m) and V(max)/K(m) for the cytokinin riboside N(6)(isopentenyl) adenosine are 3 to 5 microM and 0.021 to 0.14 L min(-1) mg(-1) protein, respectively, suggesting that adenosine is the preferred substrate for both ADK isoforms. In Arabidopsis plants, both ADK genes are expressed constitutively, with the highest steady-state mRNA levels being found in stem and root. ADK1 transcript levels were generally higher than those of ADK2. ADK enzyme activity reflected relative ADK protein levels seen in immunoblots for leaves, flowers, and stems but only poorly so for roots, siliques, and dry seeds. The catalytic properties, tissue accumulation, and expression levels of these ADKs suggest that they play a key metabolic role in the salvage synthesis of adenylates and methyl recycling in Arabidopsis. They may also contribute to cytokinin interconversion.

Abstract: The segregation of phosphorus and germanium to grain boundaries in P implanted, Si0.87Ge0.13 films deposited by chemical vapor deposition (CVD), was investigated using energy dispersive x-ray (EDX) micro-analysis. A quantitative analysis of the x-ray spectra obtained at grain boundaries showed that the excess amount of P varied with the crystallography of the boundary but that the segregation always followed an equilibrium process with an activation energy of 0.28 eV. On the other hand, Ge did not segregate to grain boundaries in either P implanted Si0.87Ge0.13 films nor in intrinsic Si1−xGex films, containing 2, 13 and 31 at.% Ge. Possible reasons for the absence of Ge segregation are discussed.

AbstractIFRS 17 Insurance Contractsis a new accounting standard currently expected to come into force on 1 January 2023. It supersedes IFRS 4 Insurance Contracts. IFRS 17 establishes key principles that entities must apply in all aspects of the accounting of insurance contracts. In doing so, the Standard aims to increase the usefulness, comparability, transparency and quality of financial statements.A fundamental concept introduced by IFRS 17 is the contractual service margin (CSM). This represents the unearned profit that an entity expects to earn as it provides services. However, as a principles-based standard, IFRS 17 results in entities having to apply significant judgement when determining the inputs, assumptions and techniques it uses to determine the CSM at each reporting period.In general, the Standard resolves broad categories of mismatches which arise under IFRS 4. Notable examples include mismatches between assets recorded at current market value and liabilities calculated using fixed discount rates as well as inconsistencies in the timing of profit recognition over the duration of an insurance contract. However, there are requirements of IFRS 17 that may create economic or accounting mismatches of its own. For example, new mismatches could arise between the measurement of underlying contracts and the corresponding reinsurance held. Additionally, mismatches can still arise between the measurement of liabilities and the assets that support the liabilities.This paper explores the technical, operational and commercial issues that arise across these and other areas focusing on the CSM. As a standard that is still very much in its infancy, and for which wider consensus on topics is yet to be achieved, this paper aims to provide readers with a deeper understanding of the issues and opportunities that accompany it.