1,060 research outputs found

    Evaluation of the effects of titanium dioxide nanoparticles on cultured Rana catesbeiana tailfin tissue

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    Nanoparticles (NPs), materials that have one dimension less than 100 nm, are used in manufacturing, health, and food products, and consumer products including cosmetics, clothing, and household appliances. Their utility to industry is derived from their high surface-area-to-volume ratios and physico-chemical properties distinct from their bulk counterparts, but the near-certainty that NPs will be released into the environment raises the possibility that they could present health risks to humans and wildlife. The thyroid hormones (THs), thyroxine, and 3,3′,5-triiodothyronine (T(3)), are involved in development and metabolism in vertebrates including humans and frogs. Many of the processes of anuran metamorphosis are analogous to human post-embryonic development and disruption of TH action can have drastic effects. These shared features make the metamorphosis of anurans an excellent model for screening for endocrine disrupting chemicals (EDCs). We used the cultured tailfin (C-fin) assay to examine the exposure effects of 0.1–10 nM (~8–800 ng/L) of three types of ~20 nm TiO(2) NPs (P25, M212, M262) and micron-sized TiO(2) (μ TiO(2)) ±10 nM T(3). The actual Ti levels were 40.9–64.7% of the nominal value. Real-time quantitative polymerase chain reaction (QPCR) was used to measure the relative amounts of mRNA transcripts encoding TH-responsive THs receptors (thra and thrb) and Rana larval keratin type I (rlk1), as well as the cellular stress-responsive heat shock protein 30 kDa (hsp30), superoxide dismutase (sod), and catalase (cat). The levels of the TH-responsive transcripts were largely unaffected by any form of TiO(2). Some significant effects on stress-related transcripts were observed upon exposure to micron-sized TiO(2), P25, and M212 while no effect was observed with M262 exposure. Therefore, the risk of adversely affecting amphibian tissue by disrupting TH-signaling or inducing cellular stress is low for these compounds relative to other previously-tested NPs

    A problem-solving approach to value-adding decision making in construction design

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    Purpose – To illustrate the use of a Value Adding Toolbox by construction industry designers when addressing customer value expectations using problem solving. Design/methodology/approach – Focused literature review establishes the need for construction industry design solutions to deliver customer value and a Value Adding Toolbox is proposed in response. Case studies validate Toolbox use and one illustrative example is provided. Interviews with prospective Toolbox users identify barriers to adoption and inform a recommended approach to organisational adoption. Findings – The Toolbox is found to be effective at helping construction designers to solve technical design problems with regard to customer expectations of value. However, designers are found to be initially reluctant to adopt the new tool. Organisation learning is therefore required to establish the importance of customer value satisfaction as a prerequisite to Toolbox adoption by designers. Originality/value – This paper provides a useful insight into the practical application of problemsolving tools by construction designers to better understand customer needs

    The tobacco industry’s past role in weight control related to smoking

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    Background: Smoking is thought to produce an appetite-suppressing effect by many smokers. Thus, the fear of body weight gain often outweighs the perception of health benefits associated with smoking cessation, particularly in adolescents. We examined whether the tobacco industry played a role in appetite and body weight control related to smoking and smoking cessation. Methods: We performed a systematic search within the archives of six major US and UK tobacco companies (American Tobacco, Philip Morris, RJ Reynolds, Lorillard, Brown & Williamson and British American Tobacco) that were Defendants in tobacco litigation settled in 1998. Findings are dated from 1949 to 1999. Results: The documents revealed the strategies planned and used by the industry to enhance effects of smoking on weight and appetite, mostly by chemical modifications of cigarettes contents. Appetite-suppressant molecules, such as tartaric acid and 2-acetylpyridine were added to some cigarettes. Conclusion: These tobacco companies played an active and not disclaimed role in the anti-appetite effects of smoking, at least in the past, by adding appetite-suppressant molecules into their cigarettes

    Long-lived photoexcited states in polydiacetylenes with different molecular and supramolecular organization

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    With the aim of determining the importance of the molecular and supramolecular organization on the excited states of polydiacetylenes, we have studied the photoinduced absorption spectra of the red form of poly[1,6-bis(3,6-didodecyl-N-carbazolyl)-2,4-hexadiyne] (polyDCHD-S) and the results compared with those of the blue form of the same polymer. An interpretation of the data is given in terms of both the conjugation length and the interbackbone separation also in relation to the photoinduced absorption spectra of both blue and red forms of poly[1,6-bis(N-carbazolyl)-2,4-hexadiyne] (polyDCHD), which does not carry the alkyl substituents on the carbazolyl side groups. Information on the above properties is derived from the analysis of the absorption and Raman spectra of this class of polydiacetylenes

    Gravitational Waves From Known Pulsars: Results From The Initial Detector Era

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    We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom

    First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

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    Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

    Predominant and novel de novo variants in 29 individuals with ALG13 deficiency: Clinical description, biomarker status, biochemical analysis, and treatment suggestions

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    Asparagine-linked glycosylation 13 homolog (ALG13) encodes a nonredundant, highly conserved, X-linked uridine diphosphate (UDP)-N-acetylglucosaminyltransferase required for the synthesis of lipid linked oligosaccharide precursor and proper N-linked glycosylation. De novo variants in ALG13 underlie a form of early infantile epileptic encephalopathy known as EIEE36, but given its essential role in glycosylation, it is also considered a congenital disorder of glycosylation (CDG), ALG13-CDG. Twenty-four previously reported ALG13-CDG cases had de novo variants, but surprisingly, unlike most forms of CDG, ALG13-CDG did not show the anticipated glycosylation defects, typically detected by altered transferrin glycosylation. Structural homology modeling of two recurrent de novo variants, p.A81T and p.N107S, suggests both are likely to impact the function of ALG13. Using a corresponding ALG13-deficient yeast strain, we show that expressing yeast ALG13 with either of the highly conserved hotspot variants rescues the observed growth defect, but not its glycosylation abnormality. We present molecular and clinical data on 29 previously unreported individuals with de novo variants in ALG13. This more than doubles the number of known cases. A key finding is that a vast majority of the individuals presents with West syndrome, a feature shared with other CDG types. Among these, the initial epileptic spasms best responded to adrenocorticotropic hormone or prednisolone, while clobazam and felbamate showed promise for continued epilepsy treatment. A ketogenic diet seems to play an important role in the treatment of these individuals.Fil: Ng, Bobby G.. Sanford Burnham Prebys Medical Discovery Institute; Estados UnidosFil: Eklund, Erik A.. Sanford Burnham Prebys Medical Discovery Institute; Estados Unidos. Lund University; SueciaFil: Shiryaev, Sergey A.. Sanford Burnham Prebys Medical Discovery Institute; Estados UnidosFil: Dong, Yin Y.. University of Oxford; Reino UnidoFil: Abbott, Mary Alice. University of Massachusetts Medical School; Estados UnidosFil: Asteggiano, Carla Gabriela. Universidad Católica de Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Estudios de las Metabolopatías Congénitas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Bamshad, Michael J.. University of Washington; Estados UnidosFil: Barr, Eileen. University of Emory; Estados UnidosFil: Bernstein, Jonathan A.. University of Stanford; Estados UnidosFil: Chelakkadan, Shabeed. Monash Children's Hospital; AustraliaFil: Christodoulou, John. Sydney Medical School; Australia. University of Melbourne; AustraliaFil: Chung, Wendy K.. Columbia University; Estados UnidosFil: Ciliberto, Michael A.. University of Iowa; Estados UnidosFil: Cousin, Janice. National Human Genome Research Institute ; Estados UnidosFil: Gardiner, Fiona. University of Melbourne; AustraliaFil: Ghosh, Suman. University of Florida; Estados UnidosFil: Graf, William D.. University of Connecticut; Estados UnidosFil: Grunewald, Stephanie. University College London; Estados UnidosFil: Hammond, Katherine. University of Alabama at Birmingahm; Estados UnidosFil: Hauser, Natalie S.. Inova, Fairfax Hospital Falls Church; Estados UnidosFil: Hoganson, George E.. University Of Illinois At Chicago; Estados UnidosFil: Houck, Kimberly M.. Baylor College of Medicine; Estados UnidosFil: Kohler, Jennefer N.. University of Stanford; Estados UnidosFil: Morava, Eva. Mayo Clinic; Estados UnidosFil: Larson, Austin A.. University Of Colorado Anschutz Medical Campus.; Estados UnidosFil: Liu, Pengfei. Baylor Genetics; Estados Unidos. Baylor College Of Medicine; Estados UnidosFil: Madathil, Sujana. University of Iowa; Estados UnidosFil: McCormack, Colleen. University of Stanford; Estados UnidosFil: Meeks, Naomi J.L.. University Of Colorado Anschutz Medical Campus.; Estados UnidosFil: Papazoglu, Gabriela Magali. Universidad Nacional de Córdoba. Facultad de Medicina. Centro de Estudios de las Metabolopatías Congénitas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin

    A CRISPR-Cas9 gene drive system targeting female reproduction in the malaria mosquito vector Anopheles gambiae.

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    Gene drive systems that enable super-Mendelian inheritance of a transgene have the potential to modify insect populations over a timeframe of a few years. We describe CRISPR-Cas9 endonuclease constructs that function as gene drive systems in Anopheles gambiae, the main vector for malaria. We identified three genes (AGAP005958, AGAP011377 and AGAP007280) that confer a recessive female-sterility phenotype upon disruption, and inserted into each locus CRISPR-Cas9 gene drive constructs designed to target and edit each gene. For each targeted locus we observed a strong gene drive at the molecular level, with transmission rates to progeny of 91.4 to 99.6%. Population modeling and cage experiments indicate that a CRISPR-Cas9 construct targeting one of these loci, AGAP007280, meets the minimum requirement for a gene drive targeting female reproduction in an insect population. These findings could expedite the development of gene drives to suppress mosquito populations to levels that do not support malaria transmission
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