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91.
Hemant J. Desai Daniel O. Acheampong Robert Hudson Richard Lacey Claire Stanley Helen Turner 《Journal of Energetic Materials》2017,35(1):109-124
The synthesis of a novel heterocyclic–telechelic polymer, α,ω-oxetanyl-telechelic poly(3-nitratomethyl-3-methyl oxetane), is described. Infrared spectroscopy (IR), gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy have been used to confirm the successful synthesis, demonstrating the presence of the telechelic-oxetanyl moieties. Synthesis of the terminal functionalities has been achieved via displacement of nitrato groups, in a manner similar to that employed with other leaving groups such as azido, bromo, and nitro, initiated by nucleophiles. In the present case, displacement occurs on the ends of a nitrato-functionalized polymer driven by the formation of sodium nitrate, which is supported by the polar aprotic solvent N,N-dimethyl formamide. The formation of an alkoxide at the polymer chain ends is favored and allows internal back-biting to the nearest carbon bearing the nitrato group, intrinsically in an SN2(i) reaction, leading to α,ω-oxetanyl functionalization. The telechelic-oxetanyl moieties have the potential to be cross-linked by chemical (e.g., acidic) or radiative (e.g., ultraviolet) curing methods without the use of high temperatures, usually below 100°C. This type of material was designed for future use as a contraband simulant, whereby it would form the predominant constituent of elastomeric composites comprising rubbery polymer with small quantities of solids, typically crystals of contraband substances, such as explosives or narcotics. This method also provides an alternative approach to ring closure and synthesis of heterocycles. 相似文献
92.
Sally Zhao 《缤纷家居》2014,(7):130-135
Extract荷兰Den Bosh的一怕老建筑,最近迎来自己的新生。那是座建于20世纪的双层Loft,在设计师Roderick Vos的改造下,它的空间一半被用于零售展示,一半用于办公思考。它模糊了设计师与顾客、艺术与生活的界限,令每一位到访者都能在幽默而单纯的氛围中,领略双享空间的专业设计精神。 相似文献
93.
Laura E. Turner Henrik Kragh Sørensen 《Centaurus; international magazine of the history of science and medicine》2013,55(4):385-411
As a reaction to the changed political landscape in Scandinavia following the dissolution of the union between Norway and Sweden in 1905, the prominent Swedish mathematician Gösta Mittag‐Leffler extended ‘a brotherly hand,’ calling for Scandinavian colleagues to meet for a congress of mathematicians in Stockholm in 1909. This event became the first in a series of biannual meetings which proved to be an important institution for Scandinavian mathematics. During the first decades after 1909, the congresses would form and consolidate themselves through the construction of a new Scandinavian identity for mathematicians which developed alongside and in relation to both international and national contexts and developments. In this paper, we shall demonstrate that these meetings served a complex set of agendas at the individual, national, and international level. In particular, they reflect a changing conception of cooperation in science for mutual cultural gain combined with a flexible institutionalisation that allowed the Scandinavian mathematicians to use the congresses for various diplomatic ambitions. We base our analyses of the Scandinavian Congresses of Mathematics on the notion of a shared ‘conational’ identity developed adjacent to national identities. We then analyse the formation, consolidation, delineation, and reflections of this institution in order to demonstrate how the efforts to unite Scandinavian mathematicians were contingent on and influenced by simultaneous currents of internationalisation and shared history, culture, and language in the Scandinavian region. 相似文献
94.
Bacteria in a water‐damaged building: associations of actinomycetes and non‐tuberculous mycobacteria with respiratory health in occupants
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J.‐H. Park J. M. Cox‐Ganser S. K. White A. S. Laney S. M. Caulfield W. A. Turner A. D. Sumner K. Kreiss 《Indoor air》2017,27(1):24-33
We examined microbial correlates of health outcomes in building occupants with a sarcoidosis cluster and excess asthma. We offered employees a questionnaire and pulmonary function testing and collected floor dust and liquid/sludge from drain tubing traps of heat pumps that were analyzed for various microbial agents. Forty‐nine percent of participants reported any symptom reflecting possible granulomatous disease (shortness of breath on exertion, flu‐like achiness, or fever and chills) weekly in the last 4 weeks. In multivariate regressions, thermophilic actinomycetes (median = 529 CFU/m2) in dust were associated with FEV1/FVC [coefficient = ?2.8 per interquartile range change, P = 0.02], percent predicted FEF25–75% (coefficient = ?12.9, P = 0.01), and any granulomatous disease‐like symptom [odds ratio (OR) = 3.1, 95% confidence interval (CI) = 1.45?6.73]. Mycobacteria (median = 658 CFU/m2) were positively associated with asthma symptoms (OR = 1.5, 95% CI = 0.97?2.43). Composite score (median = 11.5) of total bacteria from heat pumps was negatively associated with asthma (0.8, 0.71?1.00) and positively associated with FEV1/FVC (coefficient = 0.44, P = 0.095). Endotoxin (median score = 12.0) was negatively associated with two or more granulomatous disease‐like symptoms (OR = 0.8, 95% CI = 0.67?0.98) and asthma (0.8, 0.67?0.96). Fungi or (1→3)‐β‐D‐glucan in dust or heat pump traps was not associated with any health outcomes. Thermophilic actinomycetes and non‐tuberculous mycobacteria may have played a role in the occupants' respiratory outcomes in this water‐damaged building. 相似文献
95.
An investigation of how emergency vehicle lighting (EVL) can be improved is reported with reference to an analysis of police vehicle road traffic accidents (Study 1). In Study 2, 37 regular drivers were shown film clips of a marked police vehicle, in which flash rate (1 Hz, 4 Hz) and pattern (single, triple pulse) were varied on the blue Light Emitting Diode (LED) roofbar. Results indicate a 4 Hz flash rate conveys greater urgency than a 1 Hz rate, while a 1 Hz, single flash combination was ranked the least urgent of all combinations. Participants claimed they would leave significantly more space before pulling out in front of an approaching police car (gap acceptance) in the 4 Hz single pulse condition in comparison to other EVL combinations. The preliminary implications for which flash characteristics could prove most optimal for emergency service use are discussed with regard to effects on driver perception and expected driving behaviour. 相似文献
96.
97.
J. Rodney Turner 《International Journal of Project Management》2018,36(1):231-240
In this paper I make a personal reflection on my research and writings in the field of Project Management over the past 30 years. My research has primarily been about the management of the project-based organization. Within that I have researched governance, organizational behaviour, contingency, marketing, success and shareholder value. 相似文献
98.
Paolo Di Muro Laurence Lecoeuvre Rodney Turner 《International Journal of Project Management》2021,39(1):45-58
This research explores the dynamics underpinning entrepreneurial project-oriented organizations. Specifically, it focuses on how strategy and execution by projects are managed and how ambidexterity – a firm's ability to exploit old certainties while exploring new possibilities – operates as a logic. The empirical findings from an explorative longitudinal research of supercar maker Pagani Automobili in the period 2007–2019, offer an insight of a complex entrepreneurially led project-oriented organization and suggest three integrative mechanisms that describe the ambidextrous management of the interplay within and between strategy and project levels. Additionally, this research recognizes the critical role of projects also in entrepreneurial environments and suggests that the accomplishment of ambidexterity is unique in nature as it is aimed at reconciling the uniqueness of competitive propositions and that of projects within a unique entrepreneurial environment, opening avenues for more theoretical and empirical studies at the intersection of project management and entrepreneurship. 相似文献
99.
Pevindu Abeysinghe Natalie Turner Isabella Morean Garcia Eman Mosaad Hassendrini N. Peiris Murray D. Mitchell 《International journal of molecular sciences》2020,21(23)
Abnormal uterine function affects conception rate and embryo development, thereby leading to poor fertility and reproduction failure. Exosomes are a nanosized subclass of extracellular vesicles (EV) that have important functions as intercellular communicators. They contain and carry transferable bioactive substances including micro RNA (miRNA) for target cells. Elements of the cargo can provide epigenetic modifications of the recipient cells and may have crucial roles in mechanisms of reproduction. The dairy industry accounts for a substantial portion of the economy of many agricultural countries. Exosomes can enhance the expression of inflammatory mediators in the endometrium, which contribute to various inflammatory diseases in transition dairy cows. This results in reduced fertility which leads to reduced milk production and increased cow maintenance costs. Thus, gaining a clear knowledge of exosomal epigenetic modifiers is critical to improving the breeding success and profitability of dairy farms. This review provides a brief overview of how exosomal miRNA contributes to inflammatory diseases and hence to poor fertility, particularly in dairy cows. 相似文献
100.
Susanna K. P. Lau Kim-Chung Lee George C. S. Lo Vanessa S. Y. Ding Wang-Ngai Chow Tony Y. H. Ke Shirly O. T. Curreem Kelvin K. W. To Deborah T. Y. Ho Siddharth Sridhar Sally C. Y. Wong Jasper F. W. Chan Ivan F. N. Hung Kong-Hung Sze Ching-Wan Lam Kwok-Yung Yuen Patrick C. Y. Woo 《International journal of molecular sciences》2016,17(3)
To identify potential biomarkers for improving diagnosis of melioidosis, we compared plasma metabolome profiles of melioidosis patients compared to patients with other bacteremia and controls without active infection, using ultra-high-performance liquid chromatography-electrospray ionization-quadruple time-of-flight mass spectrometry. Principal component analysis (PCA) showed that the metabolomic profiles of melioidosis patients are distinguishable from bacteremia patients and controls. Using multivariate and univariate analysis, 12 significant metabolites from four lipid classes, acylcarnitine (n = 6), lysophosphatidylethanolamine (LysoPE) (n = 3), sphingomyelins (SM) (n = 2) and phosphatidylcholine (PC) (n = 1), with significantly higher levels in melioidosis patients than bacteremia patients and controls, were identified. Ten of the 12 metabolites showed area-under-receiver operating characteristic curve (AUC) >0.80 when compared both between melioidosis and bacteremia patients, and between melioidosis patients and controls. SM(d18:2/16:0) possessed the largest AUC when compared, both between melioidosis and bacteremia patients (AUC 0.998, sensitivity 100% and specificity 91.7%), and between melioidosis patients and controls (AUC 1.000, sensitivity 96.7% and specificity 100%). Our results indicate that metabolome profiling might serve as a promising approach for diagnosis of melioidosis using patient plasma, with SM(d18:2/16:0) representing a potential biomarker. Since the 12 metabolites were related to various pathways for energy and lipid metabolism, further studies may reveal their possible role in the pathogenesis and host response in melioidosis. 相似文献