349 research outputs found
Personality Traits and Cognitive Determinants – An Empirical Investigation of the Use of Smartphone Security Measures
In the last years, increasing smartphones’ capabilities have caused a paradigm shift in the way of users’ view and using mobile devices. Although researchers have started to focus on behavioral models to explain and predict human behavior, there is limited empirical research about the influence of smartphone users’ individual differences on the usage of security measures. The aim of this study is to examine the influence of individual differences on cognitive determinants of behavioral intention to use security measures. Individual differences are measured by the Five-Factor Model; cognitive determinants of behavioral intention are adapted from the validated behavioral models theory of planned behavior and technology acceptance model. An explorative, quantitative survey of 435 smartphone users is served as data basis. The results suggest that multiple facets of smartphone user’s personalities significantly affect the cognitive determinants, which indicate the behavioral intention to use security measures. From these findings, practical and theoretical implications for companies, organizations, and researchers are derived and discussed
Information security management and employees' security awareness : an analysis of behavioral determinants
[no abstract
What happens when the geomagnetic field reverses?
During geomagnetic field reversals the radiation belt high-energy proton
populations become depleted. Their energy spectra become softer, with the
trapped particles of highest energies being lost first, and eventually
recovering after a field reversal. The radiation belts rebuild in a dynamical
way with the energy spectra flattening on the average during the course of many
millennia, but without ever reaching complete steady state equilibrium between
successive geomagnetic storm events determined by southward turnings of the IMF
orientation. Considering that the entry of galactic cosmic rays and the solar
energetic particles with energies above a given threshold are strongly
controlled by the intensity of the northward component of the interplanetary
magnetic field, we speculate that at earlier epochs when the geomagnetic dipole
was reversed, the entry of these energetic particles into the geomagnetic field
was facilitated when the interplanetary magnetic field was directed northward.
Unlike in other complementary work where intensive numerical simulations have
been used, our demonstration is based on a simple analytical extension of
Stormer's theory. The access of GCR and SEP beyond geomagnetic cut-off
latitudes is enhanced during epochs when the Earth's magnetic dipole is
reduced, as already demonstrated earlier.Comment: 12 pages, 3 figures (at the end of file), paper accepted for AGU
Geophysical Monograph on "Dynamics of the Earth's Radiation Belts and Inner
Magnetosphere". Editors : D.Summers, I.R.Mann, D.N.Baker, and M.Schul
Tissue identification with micro-magnetic resonance imaging in a caprine spinal fusion model
Nonunion is a major complication of spinal
interbody fusion. Currently X-ray and computed tomography
(CT) are used for evaluating the spinal fusion process.
However, both imaging modalities have limitations in
judgment of the early stages of this fusion process, as they
only visualize mineralized bone. Magnetic resonance
imaging (MRI) could be of great value as it is able to discriminate
between different types of tissue. A feasibility
study was performed in nine animals from a goat spinal
fusion study, to evaluate the detection capacity of different
tissues with micro-MRI. In this study bioresorbable polylactic
acid cages were used. Six- and 12-months follow-up
specimens were scanned in a 6.3 T micro-MRI scanner.
After scanning, the specimens were processed for histology.
Different types of tissue as well as the degradable cage
material were identified in the fusion zone and designated as
regions of interest (ROIs). Subsequently, the location of
these ROIs was determined on the corresponding micro-
MRI image, and average signal intensities of every individual
ROI were measured. An excellent match was seen
between the histological sections and micro-MRI images.
The micro-MRI images showed quantifiable differences in
signal intensity between bone with adipose marrow, bone
with hematopoietic marrow, fibrocartilage, fibrous tissue,
and degradable implant material. In time the signal intensity
of bone with adipose marrow, bone with hematopoietic red
marrow, and of fibrous tissue remained relatively constant.
On the other hand, the signal intensity of the degradable
implant material and the fibrocartilage changed significantly
in time, indicating change of structure and
composition. In conclusion, in our model using bioresorbable
cages the MRI provides us with detailed information
about the early fusion process and may therefore, allow
early diagnosis of non-union
Moorella stamsii sp. nov., a new anaerobic thermophilic hydrogenogenic carboxydotroph isolated from digester sludge
A novel anaerobic, thermophilic, carbon monoxide-utilizing bacterium, strain E3-O, was isolated from anaerobic sludge of a municipal solid waste digester. Cells were straight rods, 0.6 to 1μm in diameter and 2 to 3 μm in length, growing as single cells or in pairs. Cells formed round terminal endospores. The temperature range for growth was 50 to 70°C, with an optimum at 65°C. The pH range for growth was 5.7 to 8.0, with an optimum at 7.5. Strain E3-O had the capability to ferment various sugars, such as fructose, galactose, glucose, mannose, raffinose, ribose, sucrose and xylose, producing mainly H2 and acetate. In addition, the isolate was able to grow with CO as the sole carbon and energy source. CO oxidation was coupled to H2 and CO2 formation. The G+C content of the genomic DNA was 54.6 mol %. Based on 16S rRNA gene sequence analysis, this bacterium is most closely related to Moorella glycerini (97% sequence identity). Based on the physiological features and phylogenetic analysis, it is proposed that strain E3-O should be classified in the genus Moorella as a new species, Moorella stamsii. The type strain of Moorella stamsii is E3-OT (=DMS 26271T=CGMCC 1.5181T).This work was possible through the financial support provided by the Portuguese Science Foundation (FCT) and the European Social Fund (POPH-QREN) through a PhD grant SFRH/BD/48965/2008 to J.I.A
Pulcherrimin formation controls growth arrest of the Bacillus subtilis biofilm
Biofilm formation by Bacillus subtilis is a communal process that culminates in the formation of architecturally complex multicellular communities. Here we reveal that the transition of the biofilm into a nonexpanding phase constitutes a distinct step in the process of biofilm development. Using genetic analysis we show that B. subtilis strains lacking the ability to synthesize pulcherriminic acid form biofilms that sustain the expansion phase, thereby linking pulcherriminic acid to growth arrest. However, production of pulcherriminic acid is not sufficient to block expansion of the biofilm. It needs to be secreted into the extracellular environment where it chelates Fe 3+ from the growth medium in a nonenzymatic reaction. Utilizing mathematical modeling and a series of experimental methodologies we show that when the level of freely available iron in the environment drops below a critical threshold, expansion of the biofilm stops. Bioinformatics analysis allows us to identify the genes required for pulcherriminic acid synthesis in other Firmicutes but the patchwork presence both within and across closely related species suggests loss of these genes through multiple independent recombination events. The seemingly counterintuitive self-restriction of growth led us to explore if there were any benefits associated with pulcherriminic acid production. We identified that pulcherriminic acid producers can prevent invasion by neighboring communities through the generation of an “iron-free” zone, thereby addressing the paradox of pulcherriminic acid production by B. subtilis. </p
A role for nickel-iron cofactors in biological carbon monoxide and carbon dioxide utilization
Ni–Fe containing enzymes are involved in the biological utilization of carbon monoxide, carbon dioxide, and hydrogen. Interest in these enzymes has increased in recent years due to hydrogen fuel initiatives and concerns over development of new methods for CO2 sequestration. One Ni–Fe enzyme called carbon monoxide dehydrogenase (CODH) is a key player in the global carbon cycle and carries out the interconversion of the environmental pollutant CO and the greenhouse gas CO[subscript 2]. The Ni–Fe center responsible for this important chemistry, the C-cluster, has been the source of much controversy, but several recent structural studies have helped to direct the field toward a unifying mechanism. Here we summarize the current state of understanding of this fascinating metallocluster.National Institutes of Health (U.S.) (GM69857)Massachusetts Institute of Technology. Energy InitiativeHoward Hughes Medical Institute. Investigato
CRITICAL SUCCESS FACTORS FOR ADOPTION OF INTEGRATED INFORMATION SYSTEMS IN HIGHER EDUCATION INSTITUTIONS – A META-ANALYSIS
Integrated information systems continuously develop into a strategic instrument for higher education institutions. In contrast to private companies, specific characteristics of higher education institutions in regards to their organizational structure as well as their management and operations require a tailored project management approach. There is need for thorough research and practical recommendations for implementation of integrated information systems in higher education institutions. This paper provides a systematic meta-analysis and a state of the art overview of critical success factors for selection and implementation of integrated information systems based on the characteristic of the higher education sector. A qualitative content analysis is applied to receive a comprehensive list of critical success factors for higher education institutions. The mostly named critical success factors are stakeholder participation, business process reengineering and communication which align well with the peculiarities of the higher education sector
- …
