Different Approaches to International Regulation of Exploitation of Deep-Ocean Ferromanganese Nodules

This article examines the advantages and disadvantages of various approaches to international regulation of the exploitation of ferromangense nodules. Some of the approaches considered are licensing of an independent operator by a UN Seabed Authority, a contract for services alternative, a joint venture arrangement, or direct exploitation. The author claims that effects on the economies of developing nations, the transfer of technology, and the location of land-based processing plants and the control of distribution of metals from nodules need not be considered as critical factors in the choice of approaches to the regulation of deep-ocean mining

A review of stress corrosion cracking of austenitic stainless steels in PWR primary water

Initial cases of stress corrosion cracking (SCC) in pressurized water reactors (PWRs) occurred mostly but not exclusively in stagnant areas like dead-legs, but recently more extensive IGSCC has occurred in normal free-flowing PWR primary water. Operational experience and laboratory data reveal that the main parameters in IGSCC include cold work and weld residual strain, oxygen, and residual and applied stress. Residual strain, which arises from manufacturing, surface grinding, and welding, should be limited by optimizing manufacturing procedures, minimizing alignment and fit-up stresses and using high-quality weld procedures. Preventing oxygen ingress in the make-up water should be pursued. Stresses created by thermal fluctuations (thermal mixing, low-leakage core operation, and start-ups) deserve more attention. Weld residual stress, fit-up stresses and local stresses from load follow must be maintained below the annealed yield stress. IGSCC should be considered in aging management and in-service inspection. Detection techniques capable of identifying IGSCC should be employed

Increased cocaine self-administration in rats lacking the serotonin transporter : a role for glutamatergic signaling in the habenula

Serotonin (5-HT) and the habenula (Hb) contribute to motivational and emotional states such as depression and drug abuse. The dorsal raphe nucleus, where 5-HT neurons originate, and the Hb are anatomically and reciprocally interconnected. Evidence exists that 5-HT influences Hb glutamatergic transmission. Using serotonin transporter knockout (SERT-/- ) rats, which show depression-like behavior and increased cocaine intake, we investigated the effect of SERT reduction on expression of genes involved in glutamate neurotransmission under both baseline conditions as well as after short-access or long-access cocaine (ShA and LgA, respectively) intake. In cocaine-na\uefve animals, SERT removal led to reduced baseline Hb mRNA levels of critical determinants of glutamate transmission, such as SLC1A2, the main glutamate transporter and N-methyl-D-aspartate (Grin1, Grin2A and Grin2B) as well as \u3b1-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (Gria1 and Gria2) receptor subunits, with no changes in the scaffolding protein Dlg4. In response to ShA and LgA cocaine intake, SLC1A2 and Grin1 mRNA levels decreased in SERT+/+ rats to levels equal of those of SERT-/- rats. Our data reveal that increased extracellular levels of 5-HT modulate glutamate neurotransmission in the Hb, serving as critical neurobiological substrate for vulnerability to cocaine addiction

Far-infrared absorption in parallel quantum wires with weak tunneling

We study collective and single-particle intersubband excitations in a system of quantum wires coupled via weak tunneling. For an isolated wire with parabolic confinement, the Kohn's theorem guarantees that the absorption spectrum represents a single sharp peak centered at the frequency given by the bare confining potential. We show that the effect of weak tunneling between two parabolic quantum wires is twofold: (i) additional peaks corresponding to single-particle excitations appear in the absorption spectrum, and (ii) the main absorption peak acquires a depolarization shift. We also show that the interplay between tunneling and weak perpendicular magnetic field drastically enhances the dispersion of single-particle excitations. The latter leads to a strong damping of the intersubband plasmon for magnetic fields exceeding a critical value.Comment: 18 pages + 6 postcript figure

Molecular cloning and characterization of a cytoplasmic cyclophilin gene in sugarcane

Cyclophilins are ubiquitous proteins with an enzymatic activity of peptidyl-prolyl cis-trans isomerase (PPIase), which play important roles in a variety of stress responsiveness. In this study, we reported the cloning and characterization of a full-length cytoplasmic cyclophilin gene in sugarcane. Sequence analysis showed the cDNA of this gene (GenBank accession number:GQ246462), termed as Sc-CyP, was 904 bp long, including a 519 bp complete ORF, the 5’ UTR of 74 bp and 3’UTR of 311 bp, plus a typical AATAA motif and poly (A) tail. It encoded the 172 amino acid polypeptide with a molecular weight of 18.4 KD and the isoelectric point of 8.68. The Sc-CyP encoding protein had the conserved site Trp128 (W128) ubiquitious of all cyclophilins in eukaryotes and the KSGKPLH48-54 region specific to cytoplasmic cyclophilins in plants. SDS-PAGE analysis and PPIase assay revealed that the expression product, with PPIase activity, was a fusion protein with a molecular weight about 25 and 18.4 kD of Sc- CyP plus 7 kD of His • Tag peptides. In real-time qPCR analysis, the Sc-CyP gene showed induced expression under PEG, NaCl, SA and H2O2 stresses, indicating it a stress-related gene for drought and salt stress, signal transduction and disease resistance response in sugarcane.Key words: Sugarcane (Saccharum officinarum), cyclophilin, PPIase, real-time quantitative PCR

Plasmodium falciparum in Ancient Egypt

The deprotonation of [FeIII(N4Py)(η1-OOH)]2+ 1 gives [FeIII(N4Py)(η2-OO)]+ 2, as unequivocally demonstrated by resonance Raman spectroscopy, and leads to the loss of alkane hydroxylation activity by 1.

Molecular cloning and expression analysis of a zeta-class glutathione S-transferase gene in sugarcane

Glutathione S-transferases (GSTs) play an important role in stress tolerance in plants. This is the first report of cloning and characterization of a zeta-class GST gene in sugarcane (GenBank Accession number: GQ246461). Sequence analysis showed that the cDNA sequence of Sc-GST gene was 829 bp, contained a 621 bp open reading frame (ORF), the 5’ untranslated region (UTR) of 65 bp and 3’UTR of 143 bp, plus the typical AATAA region and poly (A) tail. It encoded the 206 amino acid residues with a molecular mass of 23.1 KD and isoelectric point of 6.10. Protein domain prediction and multiple sequence alignment demonstrated that the conserved domain in Sc-GST at N-terminus was SSCXXRXRIA, while that at C-terminus was quebec platelet disorder (QPD), both of which were specific for zeta-type GST in eukaryotes. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and enzyme activity assay indicated that the prokaryotic expression product was a fusion protein with a molecular weight of about 30 KD, which also possessed GST enzyme activity. It was revealed in real-time quantitative polymerase chain reaction (qPCR) analysis that the Sc-GST gene had induced expression under H2O2 and Ustilago scitaminea stresses, while it was inhibited and then induced by salicylic acid (SA) stress, suggesting that it is a type of stress-tolerant gene playing a certain role in sugarcane resistance response.Key words: Saccharum officinarum, glutathione S-transferase, homology, prokaryotic expression, real-time quantitative PCR