254 research outputs found

    Surface Plasmon Resonance from Bimetallic Interface in Au–Ag Core–Shell Structure Nanowires

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    Transverse surface plasmon resonances (SPR) in Au–Ag and Ag–Au core–shell structure nanowires have been investigated by means of quasi-static theory. There are two kinds of SPR bands resulting from the outer surface of wall metal and the interface between core and wall metals, respectively. The SPR corresponding to the interface, which is similar to that of alloy particle, decreases and shifts obviously with increasing the wall thickness. However, the SPR corresponding to the outer surface, which is similar to that of pure metal particle, increases and shifts slightly with increasing the wall thickness. A mechanism based on oscillatory surface electrons under coulombic attraction is developed to illuminate the shift fashion of SPR from bimetallic core–shell interface. The net charges and extra coulombic force in metallic wall affect the SPR energy and the shift fashion

    Women's knowledge and attitudes regarding alcohol consumption in pregnancy: a national survey

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    Background. Alcohol exposure in pregnancy is a common and modifiable risk factor for poor pregnancy and child outcomes. Alcohol exposure in pregnancy can cause a range of physical and neurodevelopmental problems in the child including the Fetal Alcohol Spectrum Disorders (FASD). In order to improve prevention strategies, we sought to describe the knowledge and attitudes of women of childbearing age regarding alcohol consumption during pregnancy and its effects on the fetus.Methods. We conducted a national cross-sectional survey via computer assisted telephone interview of 1103 Australian women aged 18 to 45 years. Participants were randomly selected from the Electronic White Pages. Pregnant women were not eligible to participate. Quotas were set for age groups and a minimum of 100 participants per state to ensure a national sample reflecting the population. The questionnaire was based on a Health Canada survey with additional questions constructed by the investigators. Descriptive statistics were calculated and logistic regression analyses were used to assess associations with participants' knowledge and attitudes.Results. Of women surveyed, 61.5% had heard about effects of alcohol on the fetus and 55.3% had heard of Fetal Alcohol Syndrome. Although 92.7% agreed alcohol can affect the unborn child, 16.2% did not agree that the disabilities could be lifelong. Most women agreed that pregnant women should not drink alcohol (80.2%) and 79.2% reported having negative feelings towards pregnant women drinking alcohol. Women with higher education levels were more likely to know the effects of alcohol consumption in pregnancy (adjusted OR 5.62; 95% CI 3.20 to 9.87) but education level and knowledge were not associated with attitude.Conclusions. There was a disjunction between knowledge and attitudes towards alcohol consumption in pregnancy. These findings will assist in developing effective health promotion campaigns to reduce fetal alcohol exposure and subsequent fetal damage

    Recent Advances and Prospects in the Differentiation of Pancreatic Cells From Human Embryonic Stem Cells

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    Recent studies with human embryonic stem (hES) cells have established new protocols for substantial generation of pancreatic progenitors from definitive endoderm. These findings add to the efficient derivation of definitive endoderm, which is controlled by Wnt and Nodal pathways, and delineate a step forward in the quest for alternative β-cell sources. It also indicates that critical refining of the available strategies might help define a universal protocol for pancreatic differentiation applicable to several cell lines, therefore offering the possibility for transplantation of immune-matched or patient-specific hES–derived β-cells. We appraise here the fundamental role that bone morphogenetic protein, fibroblast growth factor, and retinoid signaling play during pancreas development, and describe a fundamental emergence of their combination in recent studies that generated pancreatic cells from hES cells. We finally enumerate some prospects that might improve further differentiation of the progenitor cells into functional β-cells needed in diabetes cell therapy

    Effect of Gas Atmosphere on Catalytic Behaviour of Zirconia, Ceria and Ceria Zirconia Catalysts in Valeric Acid Ketonization

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    [EN] Ketonization of valeric acid, which can be obtained by lignocellulosic biomass conversion, was carried out in a fixed bed flow reactor over ZrO2, 5-20 % CeO2/ZrO2 and CeO2 both under hydrogen and nitrogen stream at 628 K and atmospheric pressure. Regardless gas-carrier 10 wt% CeO2/ZrO2 was found to show higher catalytic activity compared to zirconia per se as well as other ceria modified zirconia while ceria per se exhibited very low catalytic activity. All catalysts provided higher acid conversion in H-2 than in N-2 whereas selectivity to 5-nonanone was insensitive to gas atmosphere. XRD, FTIR, UV-Vis DRS, XPS, HRTEM methods were applied to characterize catalysts in reduced and unreduced states simulating corresponding reaction conditions during acid ketonization. XRD did not reveal any changes in zirconia and ceria/zirconia lattice parameters as well as crystalline phase depending on gas atmosphere while insertion of ceria in zirconia caused notable increase in lattice parameter indicating some distortion of crystalline structure. According to XPS, FTIR and UV-Vis methods, the carrier gas was found to affect catalyst surface composition leading to alteration in Lewis acid sites ratio. Appearance of Zr3+ cations was observed on the ZrO2 surface after hydrogen pretreatment whereas only Zr4+ cations were determined using nitrogen as a gas-carrier. These changes of catalyst's surface cation composition affected corresponding activity in ketonization probably being crucial for reaction mechanism involving metal cations catalytic centers for acid adsorption and COO- stabilization at the initial step.Financial support from the Russian Foundation of Basic Research (RFBR Grant No 11-03-94001-CSIC) is gratefully acknowledged. This work was supported by the Federal Program "Scientific and Educational Cadres of Russia'' (Grant No 2012-1.5-12-000-1013-002). The authors also wish to thank Dr. Evgeniy Gerasimov, Dr. Igor Prosvirin, Dr. Demid Demidov from the Department of Physicochemical Methods at the Boreskov Institute of Catalysis for TEM and XPS measurements.Zaytseva, YA.; Panchenko, VN.; Simonov, MN.; Shutilov, AA.; Zenkovets, GA.; Renz, M.; Simakova, IL.... (2013). Effect of Gas Atmosphere on Catalytic Behaviour of Zirconia, Ceria and Ceria Zirconia Catalysts in Valeric Acid Ketonization. Topics in Catalysis. 56(9-10):846-855. https://doi.org/10.1007/s11244-013-0045-yS846855569-10Alonso DM, Bond JQ, Dumesic JA (2010) Green Chem 12:1493–1513Serrano-Ruiz JC, Wang D, Dumesic JA (2010) Green Chem 12:574–577Malhotra SL, Wong RW, Breton MP (2002) Patent US 6461417Westfechtel A, Breucker C, Gutsche B, Jeromin L, Eierdanz H, Baumann H, Schmid KH, Nonnenkamp W (1993) Patent DE 4121117Seipel W, Hensen H, Boyxen N (2001) Patent DE 19958521Tomlinson AD (2001) Patent WO 2001094522Glinski M, Kijenski J, Jakubowski A (1995) Appl Catal A Gen 128:209–217Glinski M, Kijenski J (2000) React Kinet Catal Lett 69:123–128Parida K, Mishra HK (1999) J Mol Catal A Chem 139:73–80Serrano-Ruiz JC, Dumesic JA (2009) Green Chem 11:1101–1104Serrano-Ruiz JC, Dumesic JA (2009) ChemSusChem 2:581–586Leung A, Boocock DGB, Konar SK (1995) Energy Fuels 9:913–920Gaertner CA, Serrano-Ruiz JC, Braden DJ, Dumesic JA (2010) Ind Eng Chem Res 49:6027–6033Saito N (1996) Patent JP 08198796Yakerson VI, Rubinshtein AM, Gorskaya LA (1970) Patent GB 1208802Graille J, Pioch D (1991) Patent EP 457665Pioch D, Lescure R, Graille J (1995) Ol Corps Gras Lipides 2:386–389Mueller-Erlwein E, Rosenberger B (1990) Chem Ing Tech 62:512–513Corma A, Renz M, Schaverien C (2008) ChemSusChem 1:739–741Bayer (1911) Patent DE 256622Vavon G, Apchie A (1928) Bull Soc Chim 43:667–677Thorpe JF, Kon GAR (1941) Org Synth 1:192–194Nagashima O, Sato S, Takahashi R, Sodesawa T (2005) J Mol Catal A Chem 227:231–239Klein-Homann W (1988) Patent DE 3709765Stubenrauch J, Brisha E, Vohs JM (1996) Catal Today 28:431–441Pulido A, Oliver-Tomas B, Renz M, Boronat M, and Corma A (2013) ChemSusChem 6:141–151Hendren TS, Dooley KM (2003) Catal Today 85:333–351Novothy R, Paulsen S (1963) Patent DE 1158050Kim KS, Barteau MA (1990) J Catal 125:353–375Pestman R, Van Duijne A, Pieterse JAZ, Ponec V (1995) J Mol Catal A 103:175–180Martinez R, Huff MC, Barteau MA (2004) J Catal 222:404–409Matsuoka K, Tagawa K (1985) Patent JP 61207354Shutilov AA, Simonov MN, Zaytseva YuA, Zenkovets GA, and Simakova IL (2013) Kinet Catal 54:184–192Kuriacose JC, Swaminathan R (1969) J Catal 14:348–354Swaminathan R, Kuriacose JC (1970) J Catal 16:357–362Cressely J, Farkhani D, Deluzarche A, Kiennemann A (1984) Mater Chem Phys 11:413–431Kuriacose JC, Jewur SS (1977) J Catal 50:330–341Renz M, Corma A (2004) Eur J Org Chem 2004:2036–2039Taimoor AA, Favre-Reguillon A, Vanoye L, Pitault I (2012) Catal Sci Technol 2:359–363Kustov LM (1997) Top Catal 4:131–144Emmanuel NM (1978) Usp Khim 8:1329–1396Kaspar J, Fornasiero P (2002) In: Trovarelli A (ed) Catalysis by ceria and related materials. Imperial College Press, LondonReddy DD, Chowdhury B, Smirniotis PG (2001) Appl Catal A Gen 211:19–30Rango R, Kaspar G, Meriani S, di Monte R, Graziani M (1994) Catal Lett 24:107–112Rao G, Sahu H (2001) Proc Indian Acad Sci (Chem Sci) 113:651–658Navío JA, Hidalgo MC, Colón G, Botta SG, Litter MI (2001) Langmuir 17:202–210Timofeeva MN, Jhung SH, Hwang YK, Kim DK, Panchenko VN, Melgunov MS, Chesalov YA, Chang JS (2007) Appl Catal A Gen 317:1–10Kaneko H, Taku S, Tamaura Y (2011) Sol Energy 85:2321–2330Maia TA, Assaf JM, Assaf EM (2012) Mater Chem Phys 132:1029–1034Zhou HP, Si R, Song WG, Yan CH (2009) J Solid State Chem 182:2475–2485Si R, Zhang YW, Li SJ, Lin BX, Yan CH (2004) J Phys Chem B 108:12481–12488Hadjivanov KI, Vayssilov GN (2002) Adv Catal 47:307–511Vivier L, Duprez D (2010) ChemSusChem 3:654–678Vidruk R, Landau MV, Herskowitz M, Ezersky V, Goldbourt A (2011) J Catal 282:215–227Binet C, Daturi M, Lavalley JC (1999) Catal Today 50:207–225Conesa J (1995) Surf Sci 339:337–35

    Treatment of Canine Osseous Tumors with Photodynamic Therapy: A Pilot Study

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    Photodynamic therapy uses nonthermal coherent light delivered via fiber optic cable to locally activate a photosensitive chemotherapeutic agent that ablates tumor tissue. Owing to the limitations of light penetration, it is unknown whether photodynamic therapy can treat large osseous tumors. We determined whether photodynamic therapy can induce necrosis in large osseous tumors, and if so, to quantify the volume of treated tissue. In a pilot study we treated seven dogs with spontaneous osteosarcomas of the distal radius. Tumors were imaged with MRI before and 48 hours after treatment, and the volumes of hypointense regions were compared. The treated limbs were amputated immediately after imaging at 48 hours and sectioned corresponding to the MR axial images. We identified tumor necrosis histologically; the regions of necrosis corresponded anatomically to hypointense tissue on MRI. The mean volume of necrotic tissue seen on MRI after photodynamic therapy was 21,305 mm3 compared with a pretreatment volume of 6108 mm3. These pilot data suggest photodynamic therapy penetrates relatively large canine osseous tumors and may be a useful adjunct for treatment of bone tumors

    Killing Hypoxic Cell Populations in a 3D Tumor Model with EtNBS-PDT

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    An outstanding problem in cancer therapy is the battle against treatment-resistant disease. This is especially true for ovarian cancer, where the majority of patients eventually succumb to treatment-resistant metastatic carcinomatosis. Limited perfusion and diffusion, acidosis, and hypoxia play major roles in the development of resistance to the majority of front-line therapeutic regimens. To overcome these limitations and eliminate otherwise spared cancer cells, we utilized the cationic photosensitizer EtNBS to treat hypoxic regions deep inside in vitro 3D models of metastatic ovarian cancer. Unlike standard regimens that fail to penetrate beyond ∼150 µm, EtNBS was found to not only penetrate throughout the entirety of large (>200 µm) avascular nodules, but also concentrate into the nodules' acidic and hypoxic cores. Photodynamic therapy with EtNBS was observed to be highly effective against these hypoxic regions even at low therapeutic doses, and was capable of destroying both normoxic and hypoxic regions at higher treatment levels. Imaging studies utilizing multiphoton and confocal microscopies, as well as time-lapse optical coherence tomography (TL-OCT), revealed an inside-out pattern of cell death, with apoptosis being the primary mechanism of cell killing. Critically, EtNBS-based photodynamic therapy was found to be effective against the model tumor nodules even under severe hypoxia. The inherent ability of EtNBS photodynamic therapy to impart cytotoxicity across a wide range of tumoral oxygenation levels indicates its potential to eliminate treatment-resistant cell populations

    Meta-analysis of GWAS of over 16,000 individuals with autism spectrum disorder highlights a novel locus at 10q24.32 and a significant overlap with schizophrenia.

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    To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked FilesOver the past decade genome-wide association studies (GWAS) have been applied to aid in the understanding of the biology of traits. The success of this approach is governed by the underlying effect sizes carried by the true risk variants and the corresponding statistical power to observe such effects given the study design and sample size under investigation. Previous ASD GWAS have identified genome-wide significant (GWS) risk loci; however, these studies were of only of low statistical power to identify GWS loci at the lower effect sizes (odds ratio (OR) <1.15).We conducted a large-scale coordinated international collaboration to combine independent genotyping data to improve the statistical power and aid in robust discovery of GWS loci. This study uses genome-wide genotyping data from a discovery sample (7387 ASD cases and 8567 controls) followed by meta-analysis of summary statistics from two replication sets (7783 ASD cases and 11359 controls; and 1369 ASD cases and 137308 controls).We observe a GWS locus at 10q24.32 that overlaps several genes including PITX3, which encodes a transcription factor identified as playing a role in neuronal differentiation and CUEDC2 previously reported to be associated with social skills in an independent population cohort. We also observe overlap with regions previously implicated in schizophrenia which was further supported by a strong genetic correlation between these disorders (Rg = 0.23; P = 9 × 10(-6)). We further combined these Psychiatric Genomics Consortium (PGC) ASD GWAS data with the recent PGC schizophrenia GWAS to identify additional regions which may be important in a common neurodevelopmental phenotype and identified 12 novel GWS loci. These include loci previously implicated in ASD such as FOXP1 at 3p13, ATP2B2 at 3p25.3, and a 'neurodevelopmental hub' on chromosome 8p11.23.This study is an important step in the ongoing endeavour to identify the loci which underpin the common variant signal in ASD. In addition to novel GWS loci, we have identified a significant genetic correlation with schizophrenia and association of ASD with several neurodevelopmental-related genes such as EXT1, ASTN2, MACROD2, and HDAC4.National Institutes of Mental Health (NIMH, USA) ACE Network Autism Genetic Resource Exchange (AGRE) is a program of Autism Speaks (USA) The Autism Genome Project (AGP) from Autism Speaks (USA) Canadian Institutes of Health Research (CIHR), Genome Canada Health Research Board (Ireland) Hilibrand Foundation (USA) Medical Research Council (UK) National Institutes of Health (USA) Ontario Genomics Institute University of Toronto McLaughlin Centre Simons Foundation Johns Hopkins Autism Consortium of Boston NLM Family foundation National Institute of Health grants National Health Medical Research Council Scottish Rite Spunk Fund, Inc. Rebecca and Solomon Baker Fund APEX Foundation National Alliance for Research in Schizophrenia and Affective Disorders (NARSAD) endowment fund of the Nancy Pritzker Laboratory (Stanford) Autism Society of America Janet M. Grace Pervasive Developmental Disorders Fund The Lundbeck Foundation universities and university hospitals of Aarhus and Copenhagen Stanley Foundation Centers for Disease Control and Prevention (CDC) Netherlands Scientific Organization Dutch Brain Foundation VU University Amsterdam Trinity Centre for High Performance Computing through Science Foundation Ireland Autism Genome Project (AGP) from Autism Speak
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