1,142 research outputs found
EP-1518: Evaluation of dynamic delivery quality assurance process for internal target based RapidArc
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Highly reproducible alkali metal doping system for organic crystals through enhanced diffusion of alkali metal by secondary thermal activation
In this paper, we report an efficient alkali metal doping system for organic single crystals. Our system employs an enhanced diffusion method for the introduction of alkali metal into organic single crystals by controlling the sample temperature to induce secondary thermal activation. Using this system, we achieved intercalation of potassium into picene single crystals with closed packed crystal structures. Using optical microscopy and Raman spectroscopy, we confirmed that the resulting samples were uniformly doped and became K2picene single crystal, while only parts of the crystal are doped and transformed into K2picene without secondary thermal activation. Moreover, using a customized electrical measurement system, the insulator-to-semiconductor transition of picene single crystals upon doping was confirmed by in situ electrical conductivity and ex situ temperature-dependent resistivity measurements. X-ray diffraction studies showed that potassium atoms were intercalated between molecular layers of picene, and doped samples did not show any KH- nor KOH-related peaks, indicating that picene molecules are retained without structural decomposition. During recent decades, tremendous efforts have been exerted to develop high-performance organic semiconductors and superconductors, whereas as little attention has been devoted to doped organic crystals. Our method will enable efficient alkali metal doping of organic crystals and will be a resource for future systematic studies on the electrical property changes of these organic crystals upon doping. © 2018 The Author(s
SOX2 is the determining oncogenic switch in promoting lung squamous cell carcinoma from different cells of origin
Lung squamous cell carcinoma (LSCC) is a devastating malignancy with no effective treatments, due to its complex genomic profile. Therefore, preclinical models mimicking its salient features are urgently needed. Here we describe mouse models bearing various combinations of genetic lesions predominantly found in human LSCC. We show that SOX2 but not FGFR1 overexpression in tracheobronchial basal cells combined with Cdkn2ab and Pten loss results in LSCC closely resembling the human counterpart. Interestingly, Sox2;Pten;Cdkn2ab mice develop LSCC with a more peripheral location when Club or Alveolar type 2 (AT2) cells are targeted. Our model highlights the essential role of SOX2 in commanding the squamous cell fate from different cells of origin and represents an invaluable tool for developing better intervention strategies
Enhanced production of tropane alkaloids in transgenic Scopolia parviflora hairy root cultures over-expressing putrescine N-methyl transferase (PMT) and hyoscyamine-6β-hydroxylase (H6H)
Scopolia parviflora adventitious roots were metabolically engineered by co-expression of the two gene putrescine N-methyl transferase (PMT) and hyoscyamine-6β-hydroxylase (H6H) cDNAs with the aid of Agrobacterium rhizogenes. The transformed roots developed into morphologically distinct S. parviflora PMT1 (SpPMT1), S. parviflora PMT1 (SpPMT2), and S. parviflora H6H (SpH6H) transgenic hairy root lines. Consequent to the introduction of these key enzyme genes, the production of the alkaloids hyoscyamine and scopolamine was enhanced. Among the transgenic hairy root lines, SpPMT2 line possessed the highest growth index. The treatment of transgenic hairy roots with growth regulators further enhanced the production of scopolamine. Thus, the results suggest that PMT1, PMT2, and H6H genes may not only be involved in the metabolic regulation of alkaloid production but also that these genes may play a role in the root development
Boty-II, a novel LTR retrotransposon in Botrytis cinerea B05.10 revealed by genomic sequence
Botrytis cinerea is a necrotrophic pathogen causing pre- and
post-harvest diseases in at least 235 plant species. It manifests
extraordinary genotype and phenotype variation. One of the causes of
this variation is transposable elements. Two transposable elements have
been discovered in this fungus, the retrotransposon (Boty), and the
transposon (Flipper). In this work, two complete (Boty-II-76 and
Boty-II-103) and two partial (Boty-II-95 and Boty-II-141) long terminal
repeat (LTR) retrotransposons were identified by an in silico genomic
sequence analysis. Boty-II-76 and Boty-II-103 contain 6439 bp
nucleotides with a pair of LTRs at both ends, and an internal deduced
pol gene encoding a polyprotein with reverse transcriptase and DDE
integrase domains. They are flanked by 5 bp direct repeats (ACCAT,
CTTTC). In Boty-II-141, two LTRs at both ends, and a partial internal
pol gene encoding a protein with a DDE integrase domain were
identified. In Boty-II-95, a right LTR and a partial internal pol gene
encoding a protein with no conserved domains were identified. Boty-II
uses a self-priming mechanism to initiate synthesis of reverse
transcripts. The sequence of the presumed primer binding site for
first-strand reverse transcription is 5'-TTGTACCAT-3'. The
polypurine-rich sequence for plus-strand DNA synthesis is
5'-GCCTTGAGCGGGGGGTAC-3'. Fourteen Boty-II LTRs that contain 125-158 bp
nucleotides and share 69.1 ~ 100% identities with the short inverted
terminal repeats of 5 bp (TGTCA\u2026TGACA) were discovered. Analysis
of structural features and phylogeny revealed that Boty-II is a novel
LTR retrotransposon. It could potentially be used as a novel molecular
marker for the investigation of genetic variation in B. cinerea
Selection of high berberine yielding phellodendron insulare nak. lines and the antimicrobial activity of their extracts
High berberine yielding Phellodendron insulare Nak. lines were selected by aggregate cloning method and the antimicrobial activity of their extracts was assessed. The berberine producing cork tree lines were selected by adopting a colorimetric method. In all 300 high berberine producing lines were selected with a colorimetric reagent containing 5M HCl and H2O2 and established from dissociated cell aggregates. The crude extracts from these lines showed antibacterial activities against tested Escherichia coli, Staphylococcus aureus, Salmonella typhimulium, and Listeria monocytogenes. The cork tree extracts were found to be inhibitory to these test organisms. Further the antimicrobial activity of plant extracts was on par with the berberine isolated from the extracts from native cork trees. These results have potential for developing alternative plant products as antimicrobial substances for application in agriculture and food industry
Effect of protease on growth performance and carcass characteristics of growing-finishing pigs
No Abstrac
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