562 research outputs found
The contribution of patch topology and demographic parameters to PVA predictions: the case of the European tree frog
Population viability analyses (PVA) are increasingly used in metapopulation conservation plans. Two major types of models are commonly used to assess vulnerability and to rank management options: population-based stochastic simulation models (PSM such as RAMAS or VORTEX) and stochastic patch occupancy models (SPOM). While the first set of models relies on explicit intrapatch dynamics and interpatch dispersal to predict population levels in space and time, the latter is based on spatially explicit metapopulation theory where the probability of patch occupation is predicted given the patch area and isolation (patch topology). We applied both approaches to a European tree frog (Hyla arborea) metapopulation in western Switzerland in order to evaluate the concordances of both models and their applications to conservation. Although some quantitative discrepancies appeared in terms of network occupancy and equilibrium population size, the two approaches were largely concordant regarding the ranking of patch values and sensitivities to parameters, which is encouraging given the differences in the underlying paradigms and input data
Magnetic-Torque Enhanced by Tunable Dipolar interactions
We use tunable dipolar-interactions between the spins of nitrogen-vacancy
(NV) centers in diamond to rotate a diamond crystal. Specifically, we employ
cross-relaxation between the electronic spin of pairs of NV centers in a
trapped diamond to enhance the anisotropic NV paramagnetism and thus to
increase the associated spin torque. Our observations open a path towards the
use of mechanical oscillators to detect paramagnetic defects that lack optical
transitions, to investigation of angular momentum conservation in spin
relaxation processes and to novel means of cooling the motion of mechanical
oscillators.Comment: 15 page
Culture And Universal Professional Values In Global Organizations: Is There A Divergence Or Convergence Of Cultural Values?
This article presents and discusses the theory of universal human values, the universal human values of people across cultures, and how culture and values impact organizations. This article reviews the history and research into human values, culture, and behavior, followed by reviews of Hofstede’s Cultural Dimensions and Schwartz and Bilky’s Theory of Universal Human Values.A strong connection exists between these theories and their related empirical research, not only chronologically, but also theologically and methodologically. The subjects are presented in a temporal sequence. Thus, the work of Professor Gert Hofstede is presented first; the work of Schwartz, Bilsky, is more recent, but strongly linked to prior research by Hofstede on values and culture. The objective is to improve ones understanding of work-related values, culture, and the impact that values may have on individuals in different cultural environments that are found in international organizations. This study tests to see if there is a difference in individualism scores of Mexican and American engineers when compared to Hofstede’s original study in 1980. This study also looks at the Mexican and American engineer samples to see if their scores on Hofstede’s cultural dimensions show a correlation with the scores on Schwartz’s culture-level dimensions. The study attempts to determine if there is a divergence or convergence of cultural values. Findings of the study are reported
Optical Detection of Paramagnetic Defects in a CVD-grown Diamond
The electronic spins of the nitrogen-vacancy centers (NV centers) in
Chemical-Vapor-Deposition (CVD) grown diamonds form ideal probes of magnetic
fields and temperature, as well as promising qu-bits for quantum information
processing. Studying and controlling the magnetic environment of NV centers in
such high purity crystals is thus essential for these applications. We
demonstrate optical detection of paramagnetic species, such as hydrogen-related
complexes, in a CVD-grown diamond. The resonant transfer of the NV centers'
polarized electronic spins to the electronic spins of these species generates
conspicuous features in the NV photoluminescence by employing magnetic field
scans along the [100] crystal direction. Our results offer prospects for more
detailed studies of CVD-grown processes as well as for coherent control of the
spin of novel classes of hyper-polarized paramagnetic species.Comment: 8 pages including appendi
Applying Moral Development Literature And Ethical Theories To The Administration Of Taxes In Kosovo
The population of Kosovo had suffered years of abuse, ethnic cleansing, turmoil, human atrocities, and constant conflict - the results of which plunged Kosovo into costly war. Following the war Kosovo was placed under the protection of the United Nations in 1999. Kosovo received many years of support and developmental assistance from the international community and became a sovereign nation in February 2008. It was very important for Kosovo’s government to serve the needs of the people without continued oversight and intervention by the United Nations. Public institutions are vital to the success of the government. There is no institution more important to the successful development of a sovereign nation and their economy than the ethical administration of a tax authority. In the spring of 2008, after Kosovo’s declaration of independence, this study was initiated to determine the moral maturity of the members of the Tax Authority of Kosovo. This study provides a review of the current situation in Kosovo and discusses ethical considerations in tax administration. The paper further provides a comprehensive discussion of ethical concerns and discusses the importance of moral development in the tax administration of Kosovo. Recommendations for managers and future research are presented
Warming permafrost and active layer variability at Cime Bianche, Western European Alps
The objective of this paper is to provide a first synthesis on the state and recent evolution of permafrost at the monitoring site of Cime Bianche (3100 m a.s.l.) on the Italian side of the Western Alps. The analysis is based on 7 years of ground temperature observations in two boreholes and seven surface points. The analysis aims to quantify the spatial and temporal variability of ground surface temperature in relation to snow cover, the small-scale spatial variability of the active layer thickness and current temperature trends in deep permafrost.Results show that the heterogeneity of snow cover thickness, both in space and time, is the main factor controlling ground surface temperatures and leads to a mean range of spatial variability (2.5 ± 0.1 °C) which far exceeds the mean range of observed inter-annual variability (1.6 ± 0.1 °C). The active layer thickness measured in two boreholes at a distance of 30 m shows a mean difference of 2.0 ± 0.1 m with the active layer of one borehole consistently deeper. As revealed by temperature analysis and geophysical soundings, such a difference is mainly driven by the ice/water content in the sub-surface and not by the snow cover regimes. The analysis of deep temperature time series reveals that permafrost is warming. The detected trends are statistically significant starting from a depth below 8 m with warming rates between 0.1 and 0.01 °C yr⁻¹
Planetary Nebulae Kinematics in M31
We present kinematics of 135 planetary nebulae in M31 from a survey covering
3.9 square degrees and extending out to 15 kpc from the southwest major axis
and more than 20 kpc along the minor axis. The majority of our sample, even
well outside the disk, shows significant rotational support (mean line-of-sight
velocity 116 km/s). We argue that these PN belong to the outer part of M31's
large de Vaucouleurs bulge. Only five PN have velocities clearly inconsistent
with this fast rotating bulge. All five may belong to tidal streams in M31's
outer halo. One is projected on the Northern Spur, and is counter-rotating with
respect to the disk there. Two are projected along the major axis at X=-10 kpc
and have M32-like velocities; they could be debris from that galaxy. The
remaining two halo PN are located near the center of the galaxy and their
velocities follow the gradient found by Ibata et al. (2004), implying that
these PN could belong to the Southern Stream. If M31 has a non-rotating,
pressure-supported halo, we have yet to find it, and it must be a very minor
component of the galaxy.Comment: accepted to ApJ; main body of paper is 36 pages, including 14 figure
Spectrophotometry of HII Regions, Diffuse Ionized Gas and Supernova Remnants in M31: The Transition from Photo- to Shock-Ionization
We present results of KPNO 4-m optical spectroscopy of discrete emission-line
nebulae and regions of diffuse ionized gas (DIG) in M31. Long-slit spectra of
16 positions in the NE half of M31 were obtained over a 5-15 kpc range in
radial distance from the center of the galaxy. The spectra have been used to
confirm 16 supernova remnant candidates from the Braun & Walterbos (1993)
catalog. The slits also covered 46 HII regions which show significant
differences among the various morphological types (center-brightened, diffuse,
rings). Radial gradients in emission-line ratios such as [OIII]/H and
[OII]/[OIII] are observed most prominently in the center-brightened HII
regions. These line ratio trends are either much weaker or completely absent in
the diffuse and ring nebulae. The line ratio gradients previously seen in M31
SNRs (Blair, Kirshner, & Chevalier 1981; 1982) are well reproduced by our new
data. The spectra of center-brightened HII regions and SNRs confirm previous
determinations of the radial abundance gradient in M31. We use diagnostic
diagrams which separate photoionized gas from shock-ionized gas to compare the
spectral properties of HII regions, SNRs and DIG. This analysis strengthens
earlier claims (Greenawalt, Walterbos, & Braun 1997) that the DIG in the disk
of M31 is photoionized by a dilute radiation field.Comment: 45 pages, 9 figures, 7 tables, to appear in the Astronomical Journal
(December 1999
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