oalib

OALib Journal期刊

ISSN: 2333-9721

费用：99美元

投稿

时间不限

( 2019 )

( 2018 )

( 2017 )

( 2016 )

自定义范围…

匹配条件： “Briauna Hawthorne” ，找到相关结果约58条。
列表显示的所有文章，均可免费获取
第1页/共58条
每页显示 条
Study of the Halogen Bonding between Pyridine and Perfluoroalkyl Iodide in Solution Phase Using the Combination of FTIR and 19F NMR
Briauna Hawthorne,Haiyan Fan-Hagenstein,Elizabeth Wood,Jessica Smith,Timothy Hanks
International Journal of Spectroscopy , 2013, DOI: 10.1155/2013/216518
Abstract: Halogen bonding between pyridine and heptafluoro-2-iodopropane (iso-C3F7I)/heptafluoro-1-iodopropane (1-C3F7I) was studied using a combination of FTIR and 19F NMR. The ring breathing vibration of pyridine underwent a blue shift upon the formation of halogen bonds with both iso-C3F7I and 1-C3F7I. The magnitudes of the shifts and the equilibrium constants for the halogen-bonded complex formation were found to depend not only on the structure of the halocarbon, but also on the solvent. The halogen bond also affected the Cα-F (C-F bond on the center carbon) bending and stretching vibrations in iso-C3F7I. These spectroscopic effects show some solvent dependence, but more importantly, they suggest the possibility of intermolecular halogen bonding among iso-C3F7I molecules. The systems were also examined by 19F NMR in various solvents (cyclohexane, hexane, chloroform, acetone, and acetonitrile). NMR dilution experiments support the existence of the intermolecular self-halogen bonding in both iso-C3F7I and 1-C3F7I. The binding constants for the pyridine/perfluoroalkyl iodide halogen bonding complexes formed in various solvents were obtained through NMR titration experiments. Quantum chemical calculations were used to support the FTIR and 19F NMR observations. 1. Introduction Halogen bonding, a noncovalent interaction between a halogen atom acting as an electron acceptor and an electron-rich Lewis base, has been known for nearly 150 years [1–6]. However, only recently has halogen bond started to attract wide-spread attention among scientists in a diversity of fields. Metrangolo and coworkers have reviewed the basic concepts as well as the major applications of the halogen bond [7, 8]. Examples include a wide range of applications in separation science, synthesis of liquid crystals and electronic materials, and the assembly of functional super molecules [9–18]. Recently, Meyer and Dubois [19] highlighted the application of halogen bonding to the synthesis of functional materials such as liquid crystal, nonlinear optical, magnetic conducting material, and halogen bonding based surface modification. A review by Beale et al. [20] provides an informative summary of solution thermodynamics and applications of halogen bonding. Of particular importance are their presentations of detailed thermodynamic parameters measured for the halogen bonding systems made of organic donors and halogen anions in the solution phase and which emphasized their importance in the anion recognition. Erdélyi [21] reviewed the nature of halogen bonding in solution phase and summarized the
Gisèle d’Estoc: Portraits of a decadent woman
Melanie Hawthorne
Nordlit : Tidsskrift i litteratur og kultur , 2012,
Abstract: A quarrel in the pages of the literary review Le Décadent in 1888 recalls the often belligerent existence of Gisèle d'Estoc, a shadowy figure who stalks the margins of the decadent period and whose life beyond the pages of specialized reviews has long presented something of a mystery. Who was she, and what did she look like? The first question proves the easiest to answer. Tied intimately - by love, by hatred, or by both - to numerous figures of the French decadent movement (Léo Pillard d'Arka , Laurent Tailhade, Rachilde), d'Estoc's real name was Marie-Paul Alice Courbe Desbarres. In addition to being the lover of Guy de Maupassant, and of being accused of planting a bomb at the Foyot Restaurant, d'Estoc had an independent career as an artist before launching her literary career in the 1880s. It proves more difficult to know what she looked like, even though she was often represented in paintings, drawings, and photographs. This article analyses some of these representations in order to understand why it is sometimes so difficult to see the decadent woman even when she emerges from the shadows of literary history.
Gisèle d’Estoc: Portraits of a decadent woman
Melanie Hawthorne
Nordlit : Tidsskrift i litteratur og kultur , 2012,
Abstract: A quarrel in the pages of the literary review Le Décadent in 1888 recalls the often belligerent existence of Gisèle d'Estoc, a shadowy figure who stalks the margins of the decadent period and whose life beyond the pages of specialized reviews has long presented something of a mystery. Who was she, and what did she look like? The first question proves the easiest to answer. Tied intimately - by love, by hatred, or by both - to numerous figures of the French decadent movement (Léo Pillard d'Arka , Laurent Tailhade, Rachilde), d'Estoc's real name was Marie-Paul Alice Courbe Desbarres. In addition to being the lover of Guy de Maupassant, and of being accused of planting a bomb at the Foyot Restaurant, d'Estoc had an independent career as an artist before launching her literary career in the 1880s. It proves more difficult to know what she looked like, even though she was often represented in paintings, drawings, and photographs. This article analyses some of these representations in order to understand why it is sometimes so difficult to see the decadent woman even when she emerges from the shadows of literary history.
“Sendo agora, como se f ssemos, uma família”: la os entre companheiros de viagem no navio negreiro Emília, no Rio de Janeiro e através do Mundo Atlantico
Walter Hawthorne
Revista Mundos do Trabalho , 2011, DOI: 10.5007/1984-9222.2011v3n6p7
Abstract: http://dx.doi.org/10.5007/1984-9222.2011v3n6p7 Resumo: Este artigo analisa a vida dos africanos num navio negreiro, o Emília. O navio foi capturado pelafragata inglesa Morgiana em 1821 e levado ao Rio de Janeiro. No Rio, a comiss o mista anglo-portuguesacondenou o navio pelo crime de comércio ilícito de escravos. Os africanos do Emília ficaram na condi o de“africanos livres” sob a custódia do governo local por um período de quatorze anos. Foram distribuídos entreinstitui es públicas e concessionários particulares para servir como “trabalhadores livres”. Na prática suasexperiências de trabalho foram semelhantes às de escravos. Depois de quatorze anos, um grupo dos africanoslivres do Emília voltou à áfrica juntos. O artigo prop e que a identidade mais importante para refor ar asrela es entre os africanos n o foi uma identidade étnica, mas sim uma identidade nascida no Emília, umaidentidade de companheiros de viagem. Abstract: This article analyzes the lives of a group of Africans from a slave ship, the Emilia. The ship was seizedby the British frigate Morgiana in 1821 and taken to Rio de Janeiro. There, it was condemned by the British andPortuguese mixed commission court for illegal slave trading. The recaptives from the Emilia became “liberatedAfricans” and remained under the custody of the local government for fourteen years. They were distributedamong public institutions and private hirers to serve as “free laborers”. In practice, their labor experiences wereclose to slavery. After fourteen years, a group of the Africans from the Emilia went back to Africa together. Thearticle claims that rather than an ethnic identity, the most important bond among them was the identity theycreated during the middle passage on board the Emília, a shipmate identity.
The global pharmacy workforce: a systematic review of the literature
Nicola Hawthorne, Claire Anderson
Human Resources for Health , 2009, DOI: 10.1186/1478-4491-7-48
Abstract: International peer and non-peer-reviewed literature published between January 1998 and February 2008 was analysed. Articles were collated by performing searches of appropriate databases and reference lists of relevant articles; in addition, key informants were contacted. Information that met specific quality standards and pertained to the pharmacy workforce was extracted to matrices and assigned an evidence grade.Sixty-nine papers were identified for inclusion (48 peer reviewed and 21 non-peer-reviewed). Evaluation of evidence revealed the global pharmacy workforce to be composed of increasing numbers of females who were working fewer hours; this decreased their overall full-time equivalent contribution to the workforce, compared to male pharmacists. Distribution of pharmacists was uneven with respect to location (urban/rural, less-developed/more-developed countries) and work sector (private/public). Graduates showed a preference for completing pre-registration training near where they studied as an undergraduate; this was of considerable importance to rural areas. Increases in the number of pharmacy student enrolments and pharmacy schools occurred alongside an expansion in the number and roles of pharmacy technicians. Increased international awareness and support existed for the certification, registration and regulation of pharmacy technicians and accreditation of training courses. The most common factors adding to the demand for pharmacists were increased feminization, clinical governance measures, complexity of medication therapy and increased prescriptions.To maintain and expand the future pharmacy workforce, increases in recruitment and retention will be essential, as will decreases in attrition, where possible. However, scaling up the global pharmacy workforce is a complex, multifactorial responsibility that requires coordinated action. Further research by means of prospective and comparative methods, not only surveys, is needed into feminization; decreasing
A seat at the table? Reflections on Black geographies and the limits of dialogue
Camilla Hawthorne,Kaily Heitz
- , 2018, DOI: 10.1177/2043820618780578
Abstract: This commentary uses the Black Geographies Symposium, held at UC Berkeley from October 11-12, 2017, as a point of departure to discuss the political and intellectual limits of calls for dialogue. We focus specifically on the historical exclusion of Black scholars and Black thought from human geography and understand the academy as a site for the reproduction of epistemic violence against women and people of color. Calls for dialogue within the academy that neglect to consider historically sedimented power relations—including human geography’s own entanglement with colonialism and racism—therefore commit the grave error of substituting equity for true justice. We argue instead for nonhierarchical and nonlinear modes of study that can attend to the complex geographical itineraries and interconnected struggles that continue to shape our understandings of the relations of capitalism, racism, and sexism structuring the modern world. Specifically, an intellectual praxis that begins from a place of Black humanness can enable us to tap into a wider epistemological network, one that refutes cursory lip service to Black scholarship and engages deeply with its consequences for our political and intellectual interactions
Killing Them with Kindness? In-Hive Medications May Inhibit Xenobiotic Efflux Transporters and Endanger Honey Bees
David J. Hawthorne, Galen P. Dively
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0026796
Abstract: Background Honey bees (Apis mellifera) have recently experienced higher than normal overwintering colony losses. Many factors have been evoked to explain the losses, among which are the presence of residues of pesticides and veterinary products in hives. Multiple residues are present at the same time, though most often in low concentrations so that no single product has yet been associated with losses. Involvement of a combination of residues to losses may however not be excluded. To understand the impact of an exposure to combined residues on honey bees, we propose a mechanism-based strategy, focusing here on Multi-Drug Resistance (MDR) transporters as mediators of those interactions. Methodology/Principal Findings Using whole-animal bioassays, we demonstrate through inhibition by verapamil that the widely used organophosphate and pyrethroid acaricides coumaphos and τ-fluvalinate, and three neonicotinoid insecticides: imidacloprid, acetamiprid and thiacloprid are substrates of one or more MDR transporters. Among the candidate inhibitors of honey bee MDR transporters is the in-hive antibiotic oxytetracycline. Bees prefed oxytetracycline were significantly sensitized to the acaricides coumaphos and τ-fluvalinate, suggesting that the antibiotic may interfere with the normal excretion or metabolism of these pesticides. Conclusions/Significance Many bee hives receive regular treatments of oxytetracycline and acaricides for prevention and treatment of disease and parasites. Our results suggest that seasonal co-application of these medicines to bee hives could increase the adverse effects of these and perhaps other pesticides. Our results also demonstrate the utility of a mechanism-based strategy. By identifying pesticides and apicultural medicines that are substrates and inhibitors of xenobiotic transporters we prioritize the testing of those chemical combinations most likely to result in adverse interactions.
Submersible UV-Vis Spectroscopy for Quantifying Streamwater Organic Carbon Dynamics: Implementation and Challenges before and after Forest Harvest in a Headwater Stream
Ashlee Jollymore,Mark S. Johnson,Iain Hawthorne
Sensors , 2012, DOI: 10.3390/s120403798
Abstract: Organic material, including total and dissolved organic carbon (DOC), is ubiquitous within aquatic ecosystems, playing a variety of important and diverse biogeochemical and ecological roles. Determining how land-use changes affect DOC concentrations and bioavailability within aquatic ecosystems is an important means of evaluating the effects on ecological productivity and biogeochemical cycling. This paper presents a methodology case study looking at the deployment of a submersible UV-Vis absorbance spectrophotometer (UV-Vis spectro::lyzer model, s::can, Vienna, Austria) to determine stream organic carbon dynamics within a headwater catchment located near Campbell River (British Columbia, Canada). Field-based absorbance measurements of DOC were made before and after forest harvest, highlighting the advantages of high temporal resolution compared to traditional grab sampling and laboratory measurements. Details of remote deployment are described. High-frequency DOC data is explored by resampling the 30 min time series with a range of resampling time intervals (from daily to weekly time steps). DOC export was calculated for three months from the post-harvest data and resampled time series, showing that sampling frequency has a profound effect on total DOC export. DOC exports derived from weekly measurements were found to underestimate export by as much as 30% compared to DOC export calculated from high-frequency data. Additionally, the importance of the ability to remotely monitor the system through a recently deployed wireless connection is emphasized by examining causes of prior data losses, and how such losses may be prevented through the ability to react when environmental or power disturbances cause system interruption and data loss.
Health-related Quality of Life among hospitalized older people awaiting residential aged care
Lynne C Giles, Graeme Hawthorne, Maria Crotty
Health and Quality of Life Outcomes , 2009, DOI: 10.1186/1477-7525-7-71
Abstract: Secondary analysis of data from a randomized controlled trial conducted in three public hospitals in Adelaide. A total of 320 patients in hospital beds awaiting a residential aged care bed participated. Outcome measurements included HRQoL (Assessment of Quality of Life; AQoL), functional level (Modified Barthel Index), hospital readmission rates, survival, and place of residence at four months follow-up.In this frail group the median AQoL was poor at baseline (median 0.02; 95%CI -0.01 – 0.04) and at follow-up (0.05; 95%CI 0.03 – 0.06). On leaving hospital, more than one third of participants who were moving for the first time into nursing home care rated themselves in a state worse than death (AQoL ≤ 0.0). Poor HRQoL at discharge from hospital (AQoL ≤ 0.0) was a significant predictor of mortality (HR 1.7; 95%CI 1.2 – 2.7), but not hospital readmission nor place of residence at four months follow-up. Improved function was a predictor of improved HRQoL among the surviving cohort.People making the transition to residential aged care from hospital have very poor HRQoL, but small gains in function seem to be related to improvement. While functional gains are unlikely to change discharge destination in this frail group, they can contribute to improvements in HRQoL. These gains may be of great significance for individuals nearing the end of life and should be taken into account in resource allocation.In keeping with the changes in the age structure of populations in many western countries, the demand and costs for health care for frail older people are anticipated to increase markedly over the next few decades [1], with important consequences from both individual and societal viewpoints. Traditionally older people entering residential care have been offered fewer therapy and health services as their health-related quality of life (HRQoL) is perceived to be poor [2] and deteriorating with little hope of reversal.The HRQoL among older people has been reported in a variety of
New teams in general practice
Ben Jackson,Danielle Fisher,Kamila Hawthorne
- , 2018, DOI: 10.1177/1755738018783786
Abstract: The NHS is seriously under-doctored, with general practice being one of the worst-affected specialties. GPs are a highly trusted and valued profession by patients. In addition, the ‘gatekeeping’ function and continuity of care they provide is critical to the efficiency of the services as a whole, keeps hospital admissions down, and produces better healthcare outcomes for communities and populations. Major efforts are being made to recruit new GPs and retain existing GPs, but there are serious implications for the future of primary care, and general practice in particular, as GPs struggle to cope with increased workloads. Increasing the number of GPs in the workforce is critical, and this work continues as a priority. However, a parallel stream of work has developed to consider ways in which tasks ‘traditionally’ undertaken by a GP might be diverted to new healthcare professionals within primary care teams, freeing up GPs to concentrate on the care and management of their more complex patients
第1页/共58条
每页显示 条


Home
Copyright © 2008-2020 Open Access Library. All rights reserved.