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Cryofixing single cells and multicellular specimens enhances structure and immunocytochemistry for light microscopy
Pd/C catalysts based on synthetic carbons with bi- and tri-modal pore-size distribution: Applications in flow chemistry
Synthetic carbons with hierarchical mesopores are promising for developing new catalysts for intensified continuous-flow catalysis in structured reactors.Financial support from the Engineering and Physical Sciences Research Council (Engineering Functional Materials, EP/C519736/1), the Overseas Research Students Awards Scheme and the University of Bath Research Studentship is gratefully acknowledged. The assistance of Dr Martin Jennings Dr. Chris Muryn (School of Chemistry, The University of Manchester) on ICP-OES and XPS analyses is acknowledged. KW acknowledges the Royal Society for the award of an Industry Fellowship.This is the author accepted manuscript. The final version is available from RSC via http://dx.doi.org/10.1039/C5CY01401
Pd/C catalysts based on synthetic carbons with bi- and tri-modal pore-size distribution: applications in flow chemistry
Two new types of phenolic resin-derived synthetic carbons with bi-modal and tri-modal pore-size distributions were used as supports for Pd catalysts. The catalysts were tested in chemoselective hydrogenation and hydrodehalogenation reactions in a compact multichannel flow reactor. Bi-modal and tri-modal micro-mesoporous structures of the synthetic carbons were characterised by N2 adsorption. HR-TEM, PXRD and XPS analyses were performed for characterising the synthesised catalysts. N2 adsorption revealed that tri-modal synthetic carbon possesses a well-developed hierarchical mesoporous structure (with 6.5 nm and 42 nm pores), contributing to a larger mesopore volume than the bi-modal carbon (1.57 cm3 g–1 versus 1.23 cm3 g–1). It was found that the tri-modal carbon promotes a better size distribution of Pd nanoparticles than the bi-modal carbon due to presence of hierarchical mesopore limitting the growth of Pd nanoparticles. For all the model reactions investigated, the Pd catalyst based on tri-modal synthetic carbon (Pd/triC) show high activity as well as high stability and reproducibility. The trend in reactivities of different functional groups over the Pd/triC catalyst follows a general order alkyne >> nitro > bromo >> aldehyde.Financial support from the Engineering and Physical Sciences Research Council (Engineering Functional Materials, EP/C519736/1), the Overseas Research Students Awards Scheme and the University of Bath Research Studentship is gratefully acknowledged. The assistance of Dr Martin Jennings Dr. Chris Muryn (School of Chemistry, The University of Manchester) on ICP-OES and XPS analyses is acknowledged. KW acknowledges the Royal Society for the award of an Industry Fellowship.This is the author accepted manuscript. The final version is available from RSC via http://dx.doi.org/10.1039/C5CY01401
Are we underestimating microplastic abundance in the marine environment? A comparison of microplastic capture with nets of different mesh-size
Microplastic debris is ubiquitous and yet sampling, classifying and enumerating this prolific pollutant in marine waters has proven challenging. Typically, waterborne microplastic sampling is undertaken using nets with a 333 μm mesh, which cannot account for smaller debris. In this study, we provide an estimate of the extent to which microplastic concentrations are underestimated with traditional sampling. Our efforts focus on coastal waters, where microplastics are predicted to have the greatest influence on marine life, on both sides of the North Atlantic Ocean. Microplastic debris was collected via surface trawls using 100, 333 and 500 μm nets. Our findings show that sampling using nets with a 100 μm mesh resulted in the collection of 2.5-fold and 10-fold greater microplastic concentrations compared with using 333 and 500 μm meshes respectively (P < 0.01). Based on the relationship between microplastic concentrations identified and extrapolation of our data using a power law, we estimate that microplastic concentrations could exceed 3700 microplastics m−3 if a net with a 1 μm mesh size is used. We further identified that use of finer nets resulted in the collection of significantly thinner and shorter microplastic fibres (P < 0.05). These results elucidate that estimates of marine microplastic concentrations could currently be underestimated
Mixed RG Flows and Hydrodynamics at Finite Holographic Screen
We consider quark-gluon plasma with chemical potential and study
renormalization group flows of transport coefficients in the framework of
gauge/gravity duality. We first study them using the flow equations and compare
the results with hydrodynamic results by calculating the Green functions on the
arbitrary slice. Two results match exactly. Transport coefficients at arbitrary
scale is ontained by calculating hydrodynamics Green functions. When either
momentum or charge vanishes, transport coefficients decouple from each other.Comment: 22 pages, 6 figure
Offscreen and in the chair next to your: conversational agents speaking through actual human bodies
his paper demonstrates how to interact with a conversational agent that speaks through an actual human body face-to-face and in person (i.e., offscreen). This is made possible by the cyranoid method: a technique involving a human person speech shadowing for a remote third-party (i.e., receiving their words via a covert audio-relay apparatus and repeating them aloud in real-time). When a person shadows for an artificial conversational agent source, we call the resulting hybrid an “echoborg.” We report a study in which people encountered conversational agents either through a human shadower face-to-face or via a text interface under conditions where they assumed their interlocutor to be an actual person. Our results show that the perception of a conversational agent is dramatically altered when the agent is voiced by an actual, tangible person. We discuss the potential implications this methodology has for the development of conversational agents and general person perception research
Scheme for generating entangled states of two field modes in a cavity
This paper considers a two-level atom interacting with two cavity modes with
equal frequencies. Applying a unitary transformation, the system reduces to the
analytically solvable Jaynes-Cummings model. For some particular field states,
coherent and squeezed states, the transformation between the two bare basis's,
related by the unitary transformation, becomes particularly simple. It is shown
how to generate, the highly non-classical, entangled coherent states of the two
modes, both in the zero and large detuning cases. An advantage with the zero
detuning case is that the preparation is deterministic and no atomic
measurement is needed. For the large detuning situation a measurement is
required, leaving the field in either of two orthogonal entangled coherent
states.Comment: Accepted in J. Mod. Opt.; 12 pages; Replaced with revised version.
Extended discussion of experimental realizations, earlier studies in the
field and on the frequency dependence in the adiabatic eliminatio
Testing the cognitive-behavioural maintenance models across DSM-5 bulimic-type eating disorder diagnostic groups: A multi-centre study
The original cognitive-behavioural (CB) model of bulimia nervosa, which provided the basis for the widely used CB therapy, proposed that specific dysfunctional cognitions and behaviours maintain the disorder. However, amongst treatment completers, only 40–50 % have a full and lasting response. The enhanced CB model (CB-E), upon which the enhanced version of the CB treatment was based, extended the original approach by including four additional maintenance factors. This study evaluated and compared both CB models in a large clinical treatment seeking sample (N = 679), applying both DSM-IV and DSM-5 criteria for bulimic-type eating disorders. Application of the DSM-5 criteria reduced the number of cases of DSM-IV bulimic-type eating disorders not otherwise specified to 29.6 %. Structural equation modelling analysis indicated that (a) although both models provided a good fit to the data, the CB-E model accounted for a greater proportion of variance in eating-disordered behaviours than the original one, (b) interpersonal problems, clinical perfectionism and low self-esteem were indirectly associated with dietary restraint through over-evaluation of shape and weight, (c) interpersonal problems and mood intolerance were directly linked to binge eating, whereas restraint only indirectly affected binge eating through mood intolerance, suggesting that factors other than restraint may play a more critical role in the maintenance of binge eating. In terms of strength of the associations, differences across DSM-5 bulimic-type eating disorder diagnostic groups were not observed. The results are discussed with reference to theory and research, including neurobiological findings and recent hypotheses
Biomarkers of environmental contaminants in field population of green mussel (Perna viridis) from Karnataka–Kerala coast (South West coast of India)
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