Substitution of the human beta-spectrin promoter for the human agamma-globin promoter prevents silencing of a linked human beta-globin gene in transgenic mice

During development, changes occur in both the sites of erythropoiesis and the globin genes expressed at each developmental stage. Previous work has shown that high-level expression of human beta-like globin genes in transgenic mice requires the presence of the locus control region (LCR). Models of hemoglobin switching propose that the LCR and/or stage-specific elements interact with globin gene sequences to activate specific genes in erythroid cells. To test these models, we generated transgenic mice which contain the human Agamma-globin gene linked to a 576-bp fragment containing the human beta-spectrin promoter. In these mice, the beta-spectrin Agamma-globin (betasp/Agamma) transgene was expressed at high levels in erythroid cells throughout development. Transgenic mice containing a 40-kb cosmid construct with the micro-LCR, betasp/Agamma-, psibeta-, delta-, and beta-globin genes showed no developmental switching and expressed both human gamma- and beta-globin mRNAs in erythroid cells throughout development. Mice containing control cosmids with the Agamma-globin gene promoter showed developmental switching and expressed Agamma-globin mRNA in yolk sac and fetal liver erythroid cells and beta-globin mRNA in fetal liver and adult erythroid cells. Our results suggest that replacement of the gamma-globin promoter with the beta-spectrin promoter allows the expression of the beta-globin gene. We conclude that the gamma-globin promoter is necessary and sufficient to suppress the expression of the beta-globin gene in yolk sac erythroid cells.     

Solidification of Silicon for Solar Cells

Silicon is the dominating material in solar cells. Monocrystalline and multicrystalline cells have approximately equal market shares and are produced from wafers, cut from single crystals produced by Czochralski (CZ) pulling or from polycrystalline ingots made by directional solidification, respectively. The present paper reviews how demands for lower cost, better yield, higher efficiency and use of less pure silicon in solar cells are addressed by advanced solidification processing. In monocrystalline solar silicon, careful growth control results in less point defects, and better efficiency. Continuous- or semi-continuous CZ growth processes are being developed for better productivity and lower cost. In multicrystalline solar silicon, extended defects such as dislocations and grain boundaries decrease efficiency, particularly in combination with new, less expensive, but more contaminated silicon feedstock. This problem is addressed by control of nucleation and growth of ingots with larger grains, preferred grain orientation and lower dislocation density.     

Detailed Insight into the Interaction of Bicyclic Somatostatin Analogue with Cu(II) Ions

Somatostatin analogues are useful pharmaceuticals in peptide receptor radionuclide therapy. In previous studies, we analyzed a new bicyclic somatostatin analogue (BCS) in connection with Cu(II) ions. Two characteristic sites were present in the peptide chain: the receptor- and the metal-binding site. We have already shown that this ligand can form very stable imidazole complexes with the metal ion. In this work, our aim was to characterize the intramolecular interaction that occurs in the peptide molecule. Therefore, we analyzed the coordination abilities of two cyclic ligands, i.e., P1 only with the metal binding site and P2 with both sites, but without the disulfide bond. Furthermore, we used magnetic circular dichroism (MCD) spectroscopy to better understand the coordination process. We applied this method to analyze spectra of P1, P2, and BCS, which we have described previously. Additionally, we analyzed the MCD spectra of P3 ligand, which has only the receptor binding site in its structure. We have unequivocally shown that the presence of the Phe-Trp-Lys-Thr motif and the disulfide bond significantly increases the metal binding efficiency.     

The Synthesis and Biological Evaluation of Multifunctionalised Derivatives of Noscapine as Cytotoxic Agents

Noscapine, a phthalideisoquinoline alkaloid derived from Papaver somniferum, is a well‐known antitussive drug that has a relatively safe in vitro toxicity profile. Noscapine is also known to possess weak anticancer efficacy, and since its discovery, efforts have been made to design derivatives with improved potency. Herein, the synthesis of a series of noscapine analogues, which have been modified in the 6′, 9′, 1 and 7‐positions, is described. In a previous study, replacement of the naturally occurring N‐methyl group in the 6′‐position with an N‐ethylaminocarbonyl was shown to promote cell‐cycle arrest and cytotoxicity against three cancer cell lines. Here, this modification has been combined with other structural changes that have previously been shown to improve anticancer activity, namely halo substitution in the 9′‐position, regioselective O‐demethylation to reveal a free phenol in the 7‐position, and reduction of the lactone to the corresponding cyclic ether in the 1‐position. The incorporation of new aryl substituents in the 9′‐position was also investigated. The study identified interesting new compounds able to induce G2/M cell‐cycle arrest and that possess cytotoxic activity against the human prostate carcinoma cell line PC3, the human breast adenocarcinoma cell line MCF‐7, and the human pancreatic epithelioid carcinoma cell line PANC‐1. In particular, the ethyl urea cyclic ether noscapinoids and a compound containing a 6′‐ethylaminocarbonyl along with 9′‐chloro, 7‐hydroxy and lactone moieties exhibited the most promising biological activities, with EC₅₀ values in the low micromolar range against all three cancer cell lines, and these derivatives warrant further investigation.     

Control of grain size and -orientation in multi-crystalline silicon ingots

Two different cooling rates have been imposed during the early solidification of two multi-crystalline silicon ingots with 250mm diameter and 100mm height in a pilot scale directional solidification furnace. This has been done by opening a variable heat leak system below the crucible in order to achieve a high initial cooling rate in one of the ingots. The grain-structure and -orientation of these two ingots have been investigated by light microscopy (LM) and electron backscattered diffraction (EBSD), and their electrical properties by quasi-steady state photo-conductance (QSSPC) and surface photovoltage (SPV) method. The ingot with the high initial cooling rate shows predominantly grains which are significantly larger than what is usually found in mc-Si. The minority carrier diffusion lengths measured on the large grains in the ingot with high cooling rate show higher values than those measured on the ingot with smaller grains. These results indicate that principles of grain size and -orientation control in mc-Si ingots can be applied to a pilot scale furnace, and the potential for up-scaling to industrial ingots with improved electrical properties and, thus, higher solar cell conversion efficiency.     

IP QoS across multiple management domains: practical experiences from pan-European experiments

GEANT is the pan-European 10 Gbs network interconnecting European national research and educational networks (NRENs). A Premium IP service based on the DiffServ EF PHB has been specified and implemented for this environment to provide quality of service to selected user groups on a Europe-wide scale. Basic features of Premium IP are described, and results from early experiments in the production networks of GEANT and the NRENs are presented. Next steps are proposed for achieving a fast and wide availability of Premium IP in the European research networks.     

Potentiodynamic behaviour of the rhodium/H2SO4(aq) interface in the potential range of the hydrogen and oxygen electrosorption

The electrochemical response of Rh/H₂SO₄(aq) interfaces at 25°C, subjected to different potential—time perturbation programs in the potential range of H and O electrosorption and H and O electrodesorption is reported. The H electrosorption and H electrodesorption involve the participation of at least two distinguishable adsorption states. The degree of reversibility of the corresponding electrochemical processes is appreciably influenced by the history of the electrode including the type of perturbation applied to the electrode in the O electrosorption potential range.The O electrosorption and O electrodesorption involve the formation of different surface species as it is deduced either from the charge balance or from the kinetic response of the electrochemical interface. The early stages of the anodic reaction are interpreted through a reversible charge transfer comprising the formation of OH adsorbed species which later undergoes electrochemical and chemical reactions yielding different O-containing species. The existence of the various O-containing surface species as well as the influence of the most stable ones in the H electrosorption potential range is evidenced through their potentiodynamic electrodesorption. The kinetic results of the O electrosorption are discussed in terms of aging mechanisms including anion adsorption.     

Investigation of bulk and solar cell properties of ingots cast from compensated solar grade silicon

In this work, the effect of the concurrent presence of B and P on bulk and solar cell properties of directionally solidified multicrystalline ingots from commercially compensated solar grade silicon (SoG‐Si) feedstock produced by Elkem Solar was investigated. The initial B and P content prior to the directional solidification experiment was 1260 and 762 ppba, respectively. Two reference ingots have been solidified in a silica crucible from 100% electronic grade silicon (EG‐Si) feedstock, with 332 ppba of boron added. All ingots have been cast under similar process parameters. The resistivity measurements by Four Point Probe (FPP) are in good agreement with the net dopant content, i.e., N_A − N_D for p‐type material, measured by Glow Discharge Mass Spectrometer (GDMS). Bulk lifetime measurements show a decrease in the values compared to the EG reference. Lifetime distributions show the highest values of 13 and 19 µs at approximately half ingot height, compared to 30 and 44 µs in the reference ingots. This decrease can be due to the concurrent effect of compensation and of other impurities present in the ingot. However, the content of several transition metals measured by GDMS at half ingot height was not significantly higher than that of the reference ingots. Oxygen content as measured by Fourier Transform Infra‐Red (FTIR) spectroscopy shows no significant difference compared to the references. Solar cells made from the compensated ingots and processed under standard process conditions show efficiency values up to 15.5% and fill factor values up to 78%, comparable to conventional multicrystalline silicon cells. Copyright © 2010 John Wiley & Sons, Ltd.     

Heat and light thematised in the modern architecture of Houston

Mid-twentieth-century modern architecture in Houston thematised responsiveness to the natural phenomena of heat and light despite the fact that Houston's most celebrated modern buildings were designed to be completely reliant on central air-conditioning. An examination of Houston buildings constructed from the late 1940s through the 1960s demonstrates the ways in which modern architects sought to privilege the architectural recognition of regional climatic difference while also employing modern technology to alleviate local climatic extremes of heat and humidity. The spectacular modern buildings that represent this era in Houston raise crucial questions: How did architects reconcile the doctrine of climatic responsiveness to the equally modern desire for maximum transparency? What proved more compelling: responsiveness to local circumstance or the imperatives of modern structural and mechanical engineering? Did modern architects perceive that there might be contradictions between responsiveness to climate and other aspects of modern architectural identity, such as transparency? Because concern about the roles of building design and construction in the responsible use of natural resources is current at the turn of the twenty-first century, it is pertinent to examine the ways modern architects in a particular climatic setting negotiated the issue of climatic responsiveness as modern architecture became the dominant practice.     

Dehydroacetic acid in cheese and cheese coating,results of official control in Italy

This paper reports the occurrence of dehydroacetic acid in cheese and cheese coatings collected in Italy during Agricultural Ministry Official control. Dehydroacetic acid is an antimicrobial substance not allowed to be used in EU countries as a food additive, with unknown effects on human health. Dehydroacetic acid was measured by a validated HPLC method according to Commission Decision 2002/657/EC criteria in terms of specificity, linearity, precision and accuracy, limit of detection, and limit of quantification. The method was successfully applied to 129 samples of commercial cheese coatings and related treated cheeses collected in Italy during 2017. The overall results demonstrated that about 40% of the investigated cheese coatings contained dehydroacetic acid, ranging from 0.010% to 2.5% w/w, evidencing illicit employment of this substance. Moreover, about 25% of treated cheeses contained dehydroacetic acid, from 5 to 250 mg/Kg, proving transfer of this substance from crust to cheese.