Palladate precatalysts for the formation of C-N and C-C bonds

A series of imidazolium-based palladate precatalysts has been synthesized and the catalytic activity of these air- and moisture-stable complexes evaluated as a function of the nature of the imidazolium counterion. These precatalysts can be converted under catalytic conditions to Pd-NHC species capable of enabling the Buchwald-Hartwig aryl amination and the alpha-arylation of ketones. Both reactions can be carried out efficiently under very mild operating conditions. The effectiveness of the protocol was tested on functionality-laden substrates

A culture of silence: modes of objectification and the silencing of disabled bodies

Throughout history different practices have attempted to silence the experiences of disabled people. In this paper we explore some of these practices including the medical, familial, and self-subjugating practices English-speaking Canadian polio survivors experienced throughout their lives. We analyze participant’s experiences of silence and silencing through a Foucauldian lens, drawing on the three modes of objectification to explain the institutional and cultural discourses around polio subjects that acted upon and through the polio body to silence it. Participants’ oral history accounts demonstrate how sociocultural and medical practices effectively silenced survivors from speaking about their polio experiences. However, the trope of silence is also uprooted within oral history traditions. We will demonstrate how participants broke their silence and shifted their perspectives on polio and disability, and how this process contributed to their resistance of hegemonic conceptualizations of disability as defective

Synthesis, characterization and catalytic activity of stable [(NHC)H][ZnXY2] (NHC = N-Heterocyclic carbene, X, Y = Cl, Br) species

The authors gratefully acknowledge the Royal Society (University Research Fellowship to C.S.J.C) and the EPSRC (EP/J500549/1, EP/K00445X/1) for funding. S.P. N. acknowledges support from KSU.The synthesis and characterization of imidazol(in)ium-based zinc(II) halide salts are reported. These compounds present interesting structural features and exhibit high stability. Their catalytic activity was explored in the methylation of amines with CO2 and PhSiH3.PostprintPeer reviewe

Using Social Media to Increase Accessibility to Online Teaching Resources.

The key learning points of Surgical Grand Rounds (SGR) are often not accessible at times of exam revision for students. We sought to use Twitter as an online teaching repository. A SGR Twitter profile was created. 23 SGR presentations were made accessible on Twitter over a 3 month period. 93 students were invited to complete a questionnaire assessing usage of the repository. 84 (90%) in total responded, of these, 25 (80.6%) felt that the online provision of SGR through twitter was useful . The majority (71%) felt that the online content was easily accessible. The novel use of social media is a useful adjunctive educational tool in accessing an online repository of SGR presentations

Neutral dinuclear copper(I)-NHC complexes : synthesis and application in the hydrosilylation of ketones

The authors gratefully acknowledge the Royal Society (University Research Fellowship to C.S.J.C.) for funding.The synthesis of a class of highly stable neutral dinuclear Cu(I)-NHC complexes using 1,2,4-triazole as a bridging ligand is described. Various NHCs were used to generate a library of [Cu(μ-trz)(NHC)]2, complexes. Interestingly, [Cu(μ-trz)(IPr)]2 was found to be highly active in the hydrosilylation of ketones, without the need for an external base or any other additive. A wide range of aryl and alkyl ketones, as well as sterically hindered ketones, was successfully reduced to alcohols using the lowest catalyst loading reported to date.PostprintPeer reviewe

Using platelet-to-lymphocyte ratio as a diagnostic marker in malignant ovarian tumors

Background: Ovarian malignancy, is the fifth global fatal disease for women, and the most common cause of death in Gynecological cancer. Objective was to evaluate any diagnostic role of Platelet-to-lymphocyte ratio in epithelial ovarian tumors.Methods: A prospective analysis, over 1 year; (October 2016 to October 2017). Setting: University hospital’s Gynaecological oncology centre. Subjects & Methodology: A total of 36 patients with epithelial ovarian tumors, not under any adjuvant therapy and negative for any other malignancy, or any blood diseases causing blood count changes. All subjects underwent preoperative assessment of CA125 and Platelet-to-lymphocyte ratio (PLR), followed by a staging laparotomy and the appropriate management according to the standard protocols. Postoperative histopathological confirmation of the disease type, stage and grade was done for all cases.Results: (77.8%) of the patients had early stage disease while (22.2%) had advanced stage. Neither mean platelet, lymphocytic counts, nor PLR express any significant difference between early and late stage disease. CA 125 levels, however changed significantly in advanced stages. PLR showed a statistically significant difference between the three stages of the disease (P=0.007).   There was a positive correlation between PLR and CA125 (r=0.184 and P=0.283).Conclusions: PLR rise significantly with tumor stages and correlates significantly with CA125. No significant change in PLR values with tumor type or grade. PLR might be a potential diagnostic / prognostic marker of ovarian epithelial cancer

Characteristics and drivers of forest cover change in the post-socialist era in Croatia: evidence from a mixed-methods approach

© 2016, Springer-Verlag Berlin Heidelberg.Extensive forests in Croatia represent an important biological and economic resource in Europe. They are characterised by heterogeneity in forest management practices dating back to the socialist planned economy of the pre-1991 era. In this study we investigated the difference in rates of deforestation and reforestation in private- and state-owned forests during the post-socialist period and the causal drivers of change. The selected region of Northern Croatia is characterised by a high percentage of privately owned forests with minimal national monitoring and control. We used a mixed-methods approach which combines remote sensing, statistical modelling and a household-based questionnaire survey to assess the rates of forest cover change and factors influencing those changes. The results show that predominantly privately owned forests in Northern Croatia have recorded a net forest loss of 1.8 % during the 1991–2011 period, while Croatia overall is characterised by a 10 % forest cover increase in predominantly state-owned forests. Main factors influencing forest cover changes in private forests are slope, altitude, education structure, population age and population density. The results also show that the deforestation in private forests is weakening overall, mostly due to the continuation of the de-agrarisation and de-ruralisation processes which began during socialism

Thulium Doped Fiber Amplifier (TDFA) for S-band WDM Systems

A comprehensive numerical model based on solving rate equations of a thulium-doped silica-based fiber amplifier is evaluated. The pump power and thulium-doped fiber (TDF) length for single-pass Thulium-Doped Fiber Amplifiers (TDFA) are theoretically optimized to achieve the optimum Gain and Noise Figure (NF) at the center of S-band region. The 1064 nm pump is used to provide both ground-state and excited state absorptions for amplification in the S-band region. The theoretical result is in agreement with the published experimental result

Noise figure and gain temperature dependent of praseodymium-doped fiber amplifier by using rate equations

A theoretical study of the temperature dependent noise effects of praseodymium-doped fiber amplifiers (PEDFAs) has been examined. The Pr3+-doped ZBLAN fiber amplifier pumped at 1017 nm and Pr3+-doped GeGa-sulfied fiber amplifier pumped at 1028 nm are chosen. The temperature-dependent rate and propagation equation related to four-level system consideration which is based on the population difference among amplification levels has been used. The population difference depends on pump and signal powers, Boltzman factor KB, cross-sections, noise figure (NF) and Pr3+ concentration. The numerical results obtained over the temperature range from −20 °C to + 60 °C are used to present an analytical expression for the signal gain and noise figure effects in PDFAs length and noise figure with input pump power. The amplified spontaneous emission (ASE) has been taken into account

Schematic Representation for Illustrating the Procedure of Optical Noise Figure in Erbium-doped Fiber Amplifier (EDFA) and Praseodymium-doped Fiber Amplifier (PDFA)

The erbium-doped fiber amplifier (EDFA) operating at 1530 nm wavelength and the praseodymium-doped fiber amplifier (PDFA) at 1300 nm wavelength are promising components for optical fiber communications due to their high gain, high saturation powers, low noise and low crosstalk. In this paper, using comprehensive models which take into account the spectroscopic properties of the fiber amplifiers, we have analyzed the temperature-dependent noise figure effects on both EDFAs and PDFAs