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HRM practices used to promote pro-environmental behavior: a UK survey
To date, the extent to which UK organizations use human resource management (HRM) practices to promote pro-environmental behavior through workplace HRM policies and initiatives is under-researched within the literature. Therefore, this paper presents results of a survey investigating current HRM practices used to promote pro-environmental behavior in a sample of 214 UK organizations representing different sizes and industry sectors. Overall, findings indicated that HRM practices are not used to a great extent to encourage employees to become more pro-environmental. The most prevalent practices used within organizations incorporated elements of management involvement supporting the idea that managers are the gatekeepers to environmental performance. Although organizations indicated that some HRM practices were more effective than others at encouraging pro-environmental behavior in their staff, only a very small percentage of organizations actually conducted any form of evaluation; organizations consequently lack clear evidence as to whether their HRM practices actually result in employee behavior change. Practical implications and future research directions are discussed
A mathematical model for breath gas analysis of volatile organic compounds with special emphasis on acetone
Recommended standardized procedures for determining exhaled lower respiratory
nitric oxide and nasal nitric oxide have been developed by task forces of the
European Respiratory Society and the American Thoracic Society. These
recommendations have paved the way for the measurement of nitric oxide to
become a diagnostic tool for specific clinical applications. It would be
desirable to develop similar guidelines for the sampling of other trace gases
in exhaled breath, especially volatile organic compounds (VOCs) which reflect
ongoing metabolism. The concentrations of water-soluble, blood-borne substances
in exhaled breath are influenced by: (i) breathing patterns affecting gas
exchange in the conducting airways; (ii) the concentrations in the
tracheo-bronchial lining fluid; (iii) the alveolar and systemic concentrations
of the compound. The classical Farhi equation takes only the alveolar
concentrations into account. Real-time measurements of acetone in end-tidal
breath under an ergometer challenge show characteristics which cannot be
explained within the Farhi setting. Here we develop a compartment model that
reliably captures these profiles and is capable of relating breath to the
systemic concentrations of acetone. By comparison with experimental data it is
inferred that the major part of variability in breath acetone concentrations
(e.g., in response to moderate exercise or altered breathing patterns) can be
attributed to airway gas exchange, with minimal changes of the underlying blood
and tissue concentrations. Moreover, it is deduced that measured end-tidal
breath concentrations of acetone determined during resting conditions and free
breathing will be rather poor indicators for endogenous levels. Particularly,
the current formulation includes the classical Farhi and the Scheid series
inhomogeneity model as special limiting cases.Comment: 38 page
The role of mathematical modeling in VOC analysis using isoprene as a prototypic example
Isoprene is one of the most abundant endogenous volatile organic compounds
(VOCs) contained in human breath and is considered to be a potentially useful
biomarker for diagnostic and monitoring purposes. However, neither the exact
biochemical origin of isoprene nor its physiological role are understood in
sufficient depth, thus hindering the validation of breath isoprene tests in
clinical routine.
Exhaled isoprene concentrations are reported to change under different
clinical and physiological conditions, especially in response to enhanced
cardiovascular and respiratory activity. Investigating isoprene exhalation
kinetics under dynamical exercise helps to gather the relevant experimental
information for understanding the gas exchange phenomena associated with this
important VOC.
A first model for isoprene in exhaled breath has been developed by our
research group. In the present paper, we aim at giving a concise overview of
this model and describe its role in providing supportive evidence for a
peripheral (extrahepatic) source of isoprene. In this sense, the results
presented here may enable a new perspective on the biochemical processes
governing isoprene formation in the human body.Comment: 17 page
Isoprene and acetone concentration profiles during exercise on an ergometer
A real-time recording setup combining exhaled breath VOC measurements by
proton transfer reaction mass spectrometry (PTR-MS) with hemodynamic and
respiratory data is presented. Continuous automatic sampling of exhaled breath
is implemented on the basis of measured respiratory flow: a flow-controlled
shutter mechanism guarantees that only end-tidal exhalation segments are drawn
into the mass spectrometer for analysis.
Exhaled breath concentration profiles of two prototypic compounds, isoprene
and acetone, during several exercise regimes were acquired, reaffirming and
complementing earlier experimental findings regarding the dynamic response of
these compounds reported by Senthilmohan et al. [1] and Karl et al. [2]. While
isoprene tends to react very sensitively to changes in pulmonary ventilation
and perfusion due to its lipophilic behavior and low Henry constant,
hydrophilic acetone shows a rather stable behavior. Characteristic (median)
values for breath isoprene concentration and molar flow, i.e., the amount of
isoprene exhaled per minute are 100 ppb and 29 nmol/min, respectively, with
some intra-individual day-to-day variation. At the onset of exercise breath
isoprene concentration increases drastically, usually by a factor of ~3-4
within about one minute. Due to a simultaneous increase in ventilation, the
associated rise in molar flow is even more pronounced, leading to a ratio
between peak molar flow and molar flow at rest of ~11.
Our setup holds great potential in capturing continuous dynamics of
non-polar, low-soluble VOCs over a wide measurement range with simultaneous
appraisal of decisive physiological factors affecting exhalation kinetics.Comment: 35 page
Can local knowledge make the difference? Rethinking university's community engagement and prospect for sustainable development
Against the backdrop of Africa's quest for development, there have been emerging demands for its universities to do more in contributing to development drives beyond their immediate sphere of operation. Drawing on an instrumental case study within an African community, this paper heartens a reconsideration of African universities' community engagement as a catalyst for sustainable development. It ascertains that it would be beneficial to the university and its mission to foster sustainable development when local voices are assimilated within its knowledge creation, diffusion and societal engagement objectives. Whilst this has the potential to instigate the university's engagement to address local and regional concerns and promote relevant development, this would be predicated on targeted collaborative engagement frameworks, underpinned by mutual trust
Adenosine induces growth-cone turning of sensory neurons
The formation of appropriate connections between neurons and their specific targets is an essential step during development and repair of the nervous system. Growth cones are located at the leading edges of the growing neurites and respond to environmental cues in order to be guided to their final targets. Directional information can be coded by concentration gradients of substrate-bound or diffusible-guidance molecules. Here we show that concentration gradients of adenosine stimulate growth cones of sensory neurons (dorsal root ganglia) from chicken embryos to turn towards the adenosine source. This response is mediated by adenosine receptors. The subsequent signal transduction process involves cAMP. It may be speculated that the in vivo function of this response is concerned with the formation or the repair and regeneration of the peripheral nervous system
Search for low-mass dilepton resonances in Higgs boson decays to four-lepton final states in protonâproton collisions at âs=13TeV
A search for low-mass dilepton resonances in Higgs boson decays is conducted in the four-lepton final state.
The decay is assumed to proceed via a pair of beyond the standard model particles, or one such particle and a Z boson. The
search uses protonâproton collision data collected with the
CMS detector at the CERN LHC, corresponding to an integrated luminosity of 137 fbâ1, at a center-of-mass energy
âs = 13 TeV. No significant deviation from the standard
model expectation is observed. Upper limits at 95% confidence level are set on model-independent Higgs boson decay
branching fractions. Additionally, limits on dark photon and
axion-like particle production, based on two specific models,
are reported
MUSiC: a model-unspecific search for new physics in protonâproton collisions at âs=13TeV
Results of the Model Unspecific Search in CMS (MUSiC), using protonâproton collision data recorded at the LHC at a centre-of-mass energy of 13TeV, corresponding to an integrated luminosity of 35.9fb-1, are presented. The MUSiC analysis searches for anomalies that could be signatures of physics beyond the standard model. The analysis is based on the comparison of observed data with the standard model prediction, as determined from simulation, in several hundred final states and multiple kinematic distributions. Events containing at least one electron or muon are classified based on their final state topology, and an automated search algorithm surveys the observed data for deviations from the prediction. The sensitivity of the search is validated using multiple methods. No significant deviations from the predictions have been observed. For a wide range of final state topologies, agreement is found between the data and the standard model simulation. This analysis complements dedicated search analyses by significantly expanding the range of final states covered using a model independent approach with the largest data set to date to probe phase space regions beyond the reach of previous general searches
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