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Livestock Protection Tools for California Ranchers
Conflicts between livestock and predators are perhaps inevitable, especially on extensively managed rangelands This publication helps producers evaluate livestock lethal and non-lethal protection tools that may fit their site-specific needs
Polypyrrole-Fe2O3 nanohybrid materials for electrochemical storage
We report on the synthesis and electrochemical characterization of nanohybrid polypyrrole (PPy) (PPy/Fe2O3) materials for electrochemical storage applications. We have shown that the incorporation of nanoparticles inside the PPy notably increases the charge storage capability in comparison to the “pure” conducting polymer. Incorporation of large anions, i.e., paratoluenesulfonate, allows a further improvement in the capacity. These charge storage modifications have been attributed to the morphology of the composite in which the particle sizes and the specific surface area are modified with the incorporation of nanoparticles. High capacity and stability have been obtained in PC/NEt4BF4 (at 20 mV/s), i.e., 47 mAh/g, with only a 3% charge loss after one thousand cyles. The kinetics of charge–discharge is also improved by the hybrid nanocomposite morphology modifications, which increase the rate of insertion–expulsion of counter anions in the bulk of the film. A room temperature ionic liquid such as imidazolium trifluoromethanesulfonimide seems to be a promising electrolyte because it further increases the capacity up to 53 mAh/g with a high stability during charge–discharge processes
‘Talent-spotting’ or ‘social magic’? Inequality, cultural sorting and constructions of the ideal graduate in elite professions
Graduate outcomes – including rates of employment and earnings – are marked by persistent
inequalities related to social class, as well as gender, ethnicity and institution. Despite national
policy agendas related to social mobility and ‘fair access to the professions’, high-status occupations
are disproportionately composed of those from socially privileged backgrounds, and evidence
suggests that in recent decades many professions have become less socially representative.
This article makes an original contribution to sociological studies of inequalities in graduate
transitions and elite reproduction through a distinct focus on the ‘pre-hiring’ practices of graduate
employers. It does this through a critical analysis of the graduate recruitment material of two
popular graduate employers. It shows how, despite espousing commitments to diversity and
inclusion, constructions of the ‘ideal’ graduate privilege individuals who can mobilise and embody
certain valued capitals. Using Bourdieusian concepts of ‘social magic’ and ‘institutional habitus’, the
article argues that more attention must be paid to how graduate employers’ practices constitute
tacit processes of social exclusion and thus militate against the achievement of more equitable
graduate outcomes and fair access to the ‘top jobs
Social enterprise policy design: Constructing social enterprise in the UK and Korea
Taking the elusive definition of social enterprise as its starting point, this study seeks to understand the impact of government policies on the development of social enterprises in the national contexts of the UK and South Korea. The social construction of target populations is utilised as a theoretical framework in order to identify which factors influence government policy. A comparison of the two countries over a 14-year period from 1997 to 2010 reveals that, despite very different contexts, governments in both countries have taken an instrumental approach to social enterprise. This tendency is more pronounced in Korea however, where government has limited the input of stakeholders and used an approval system to control access to the social enterprise name. The study concludes by recommending a more value-oriented approach to social enterprise
Phase transitions in biological membranes
Native membranes of biological cells display melting transitions of their
lipids at a temperature of 10-20 degrees below body temperature. Such
transitions can be observed in various bacterial cells, in nerves, in cancer
cells, but also in lung surfactant. It seems as if the presence of transitions
slightly below physiological temperature is a generic property of most cells.
They are important because they influence many physical properties of the
membranes. At the transition temperature, membranes display a larger
permeability that is accompanied by ion-channel-like phenomena even in the
complete absence of proteins. Membranes are softer, which implies that
phenomena such as endocytosis and exocytosis are facilitated. Mechanical signal
propagation phenomena related to nerve pulses are strongly enhanced. The
position of transitions can be affected by changes in temperature, pressure, pH
and salt concentration or by the presence of anesthetics. Thus, even at
physiological temperature, these transitions are of relevance. There position
and thereby the physical properties of the membrane can be controlled by
changes in the intensive thermodynamic variables. Here, we review some of the
experimental findings and the thermodynamics that describes the control of the
membrane function.Comment: 23 pages, 15 figure
Two-Nucleon Momentum Distributions Measured in 3He(e,e'pp)n
We have measured the 3He(e,e'pp)n reaction at 2.2 GeV over a wide kinematic
range. The kinetic energy distribution for `fast' nucleons (p > 250 MeV/c)
peaks where two nucleons each have 20% or less, and the third nucleon has most
of the transferred energy. These fast pp and pn pairs are back-to-back with
little momentum along the three-momentum transfer, indicating that they are
spectators. Experimental and theoretical evidence indicates that we have
measured distorted two-nucleon momentum distributions by striking the third
nucleon and detecting the spectator correlated pair.Comment: 6 pages, 5 figures, submitted to PR
Manipulating the monolayer : responsive and reversible control of colloidal inorganic nanoparticle properties
Funding: EPSRC EP/K016342/1; Leverhulme Trust: RPG-2015-042For a wide range of nanomaterials, surface-bound molecules play a central role in defining properties, and are key to integration with other components – be they molecules, surfaces, or other nanoparticles. Predictable and general methods for manipulating the surface monolayer are therefore crucial to exploiting this new region of chemical space. This review highlights limitations of the few established methods for controlling nanoparticle-bound molecular functionality, then focuses on emerging new strategies. In particular, approaches that can achieve stimuli-responsive and reversible modification of surface-bound molecules in colloidal solution are examined, with an emphasis on using these methods to control nanoparticle properties such as solvent compatibility, catalytic activity and cytotoxicity. Finally, the outstanding challenges and future potential for precisely controlled nanoparticle bound monolayers are discussed.Publisher PDFPeer reviewe
Inactivation combined with cell lysis of Pseudomonas putida using a low pressure carbon dioxide microbubble technology
BACKGROUND
Inactivation processes can be classified into non-thermal inactivation methods such as ethylene oxide and γ-radiation, and thermal methods such as autoclaving. The ability of carbon dioxide enriched microbubbles to inactivate Pseudomonas putida suspended in physiological saline, as a non-thermal sterilisation method, was investigated in this study with many operational advantages over both traditional thermal and non-thermal sterilisation methods.
RESULTS
Introducing carbon dioxide enriched microbubbles can achieve ∼2-Log reduction in the bacterial population after 90 min of treatment, addition of ethanol to the inactivation solution further enhanced the inactivation process to achieve 3, 2.5 and 3.5-Log reduction for 2%, 5% and 10 %( v/v) ethanol, respectively. A range of morphological changes was observed on Pseudomonas cells after each treatment, and these changes extended from changing cell shape from rod shape to coccus shape to severe lesions and cell death. Pseudomonas putida KT 2440 was used as a model of gram-negative bacteria.
CONCLUSION
Using CO2 enriched microbubbles technology has many advantages such as efficient energy consumption (no heat source), avoidance of toxic and corrosive reagents, and in situ treatment. In addition, many findings from this study could apply to other gram-negative bacteria
Searching for a Stochastic Background of Gravitational Waves with LIGO
The Laser Interferometer Gravitational-wave Observatory (LIGO) has performed
the fourth science run, S4, with significantly improved interferometer
sensitivities with respect to previous runs. Using data acquired during this
science run, we place a limit on the amplitude of a stochastic background of
gravitational waves. For a frequency independent spectrum, the new limit is
. This is currently the most sensitive
result in the frequency range 51-150 Hz, with a factor of 13 improvement over
the previous LIGO result. We discuss complementarity of the new result with
other constraints on a stochastic background of gravitational waves, and we
investigate implications of the new result for different models of this
background.Comment: 37 pages, 16 figure
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