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Are all net generation students the same? The frequency of technology use at university
This paper looks at the results of a longitudinal study on how frequently the Net Generation students (i.e. those born in the 1980s) use technologies in their first year of university. Eight technology groupings were explored including web 2.0, social networking and computer software. The research investigated whether older Net Generation students (21-25 years) used technologies differently to the younger Net Generation students (≤20 years). Additional factors such as gender, university type (distance-learning or place-based) and nationality (UK or International) were accounted for during the study. The research found that nationality and university type were influential factors in determining the frequency of use across all technologies at the beginning of the academic year and continued to be influencing factors along with gender at the end of the academic year. Age only seemed to be an important factor for the use of Web 2.0 and social networking sites but these uses of technology were also dependent on students’ university type, gender and nationality. Thus these demographic and social factors have to be considered when analysing technology use or designing educational tools. The findings of this study have implications for research into age-related differences in students’ use of digital technologies and universities’ digital technologies training provision
Normal faulting and landsliding in morpho-structural domes related to buried salt stocks, Zagros Mountains, Iran. Insights into salt breakout
Normal faulting in domal structures above diapirs has important implications in hydrocarbon geoscience, but studies on surface faulting on exposed growing domes are scarce. Moreover, there is limited work addressing the erosional processes involved in the unroofing of active diapirs preceding salt emergence. This investigation analyses two morpho-structural domes (Gavbast Dome: GD; Kooh Bedoo Dome: KBD) associated with growing anticlines related to the rejuvenation of precursor buried salt stocks in the Zagros Mountains. The structural relief of the domes (1330 m in GD and 400 m in KBD) and the available chronological data on fold development indicate long-term uplift rates of around 0.1–0.4 mm/yr. GD displays three domains with different fault patterns: (1) fold-normal grabens in one half; (2) polygonal faulting with multiple enclosed graben depressions in the crest; and (3) fold-parallel faulting on the other half. KBD shows a major fold-normal graben restricted to the crest and one flank of the dome. The lack of the typical radial pattern related to multidirectional hoop extension can be attributed the suppression of extension in the fold-normal direction by regional shortening. Other factors such as complexities in the folding structure, outer-arc extension in the anticline crests, and plan geometry seem to play a local control on fault patterns. The studied domes display an extraordinarily high density of large slope movements, indicating that they play an instrumental role in the unroofing process. The slope failures, with sliding planes mainly developed in argillaceous units overlain by thick limestone packages, include incipient planar rock slides more than 5 km2 in area expressed as buckle folds in the lower part of the slopes. The main preparatory factors involved in the development of these slope collapses include rock mass weakening by faulting and slope over-steepening, both related to doming. Our detailed mapping and the examination of a number of salt diapirs in the Fars Arc suggest that episodic landsliding and more gradual fluvial dissection, often controlled by grabens, are the main erosional processes involved in the unroofing of active diapirs leading to salt emergence
Statistical properties of a localization-delocalization transition induced by correlated disorder
The exact probability distributions of the resistance, the conductance and
the transmission are calculated for the one-dimensional Anderson model with
long-range correlated off-diagonal disorder at E=0. It is proved that despite
of the Anderson transition in 3D, the functional form of the resistance (and
its related variables) distribution function does not change when there exists
a Metal-Insulator transition induced by correlation between disorders.
Furthermore, we derive analytically all statistical moments of the resistance,
the transmission and the Lyapunov Exponent. The growth rate of the average and
typical resistance decreases when the Hurst exponent tends to its critical
value () from the insulating regime.
In the metallic regime , the distributions become independent of
size. Therefore, the resistance and the transmission fluctuations do not
diverge with system size in the thermodynamic limit
Electronic structure of nanoscale iron oxide particles measured by scanning tunneling and photoelectron spectroscopies
We have investigated the electronic structure of nano-sized iron oxide by
scanning tunnelling microscopy (STM) and spectroscopy (STS) as well as by
photoelectron spectroscopy. Nano particles were produced by thermal treatment
of Ferritin molecules containing a self-assembled core of iron oxide. Depending
on the thermal treatment we were able to prepare different phases of iron oxide
nanoparticles resembling gamma-Fe2O3, alpha-Fe2O3, and a phase which apparently
contains both gamma-Fe2O3 and alpha-Fe2O3. Changes to the electronic structure
of these materials were studied under reducing conditions. We show that the
surface band gap of the electronic excitation spectrum can differ from that of
bulk material and is dominated by surface effects.Comment: REVTeX, 6 pages, 10 figures, submitted to PR
Short Communication - Comparision of microscopy and RDTs techniques for laboratory detection of malaria
The development of rapid and specific diagnostic test to identify individuals infected with malaria is important to control severe public health impact of this disease.This study evaluated the ability of rapid malaria diagnostic test (BIOTEC Malaria P.v/P.f rapid device) to detect Plasmodium falciparum and Plasmodium vivax malaria during out break in Chabahar province of Sistan and Balouchestan in Iran. Whole blood samples were obtained from 250 suspected malaria patients. Results from these kit were compared to the reading obtained from 100 fields of Giemsa-stained thick smear blood film.This test is rapid (15 min) for malaria detection. The device is coated with monoclonal antibodies against P. falciparum histidine rich protein-2 (PfHRP2) and enzyme parasite lactate dehydrogenase isomer of P. vivax (PLDH) . A total of 55% samples (138 of 250) were positive by blood films, while 54% samples (136 of 250) were positive by malaria P.v/P.f rapid device. The blood film indicated that 81% (112 of 138) of patients were positive for P.vivax and 19% (26 of 138) of patients were positive for P. falciparum. The malaria P.v/P.f rapid device showed that 79.6% (110 of 138) were positive for P.vivax and 1.4% (2 of 138) were negative. 19% (26 of 138) were positive for P. falciparum. These results demonstrated that the malaria P.v/P.f rapid device had sensitivity of 98.5% and specificity of 100% when compared to traditional blood films. The malaria P.v/P.f rapid device showed an excellent correlation with traditional blood films in identification of both P. vivax and P. falciparum malaria. At present for diagnosis of malaria in endemic area, this kit is rather expensive when compared to microscopy. Neverthless, it is very useful for remote areas where the necessary facilities for microscopic examination are not accessible
Self Assembly of Soft Matter Quasicrystals and Their Approximants
The surprising recent discoveries of quasicrystals and their approximants in
soft matter systems poses the intriguing possibility that these structures can
be realized in a broad range of nano- and micro-scale assemblies. It has been
theorized that soft matter quasicrystals and approximants are largely
entropically stabilized, but the thermodynamic mechanism underlying their
formation remains elusive. Here, we use computer simulation and free energy
calculations to demonstrate a simple design heuristic for assembling
quasicrystals and approximants in soft matter systems. Our study builds on
previous simulation studies of the self-assembly of dodecagonal quasicrystals
and approximants in minimal systems of spherical particles with complex,
highly-specific interaction potentials. We demonstrate an alternative
entropy-based approach for assembling dodecagonal quasicrystals and
approximants based solely on particle functionalization and shape, thereby
recasting the interaction-potential-based assembly strategy in terms of
simpler-to-achieve bonded and excluded-volume interactions. Here, spherical
building blocks are functionalized with mobile surface entities to encourage
the formation of structures with low surface contact area, including
non-close-packed and polytetrahedral structures. The building blocks also
possess shape polydispersity, where a subset of the building blocks deviate
from the ideal spherical shape, discouraging the formation of close-packed
crystals. We show that three different model systems with both of these
features -- mobile surface entities and shape polydispersity -- consistently
assemble quasicrystals and/or approximants. We argue that this design strategy
can be widely exploited to assemble quasicrystals and approximants on the nano-
and micro- scales. In addition, our results further elucidate the formation of
soft matter quasicrystals in experiment.Comment: 12 pages 6 figure
Quantum teleportation with nonclassical correlated states in noninertial frames
Quantum teleportation is studied in noninertial frame, for fermionic case,
when Alice and Bob share a general nonclassical correlated state. In
noninertial frames two fidelities of teleportation are given. It is found that
the average fidelity of teleportation from a separable and nonclassical
correlated state is increasing with the amount of nonclassical correlation of
the state. However, for any particular nonclassical correlated state, the
fidelity of teleportation decreases by increasing the acceleration.Comment: 10 pages, 3 figures, expanded version to appear in Quantum Inf.
Proces
Linking genomics and metabolomics to chart specialized metabolic diversity
Microbial and plant specialized metabolites constitute an immense chemical diversity, and play key roles in mediating ecological interactions between organisms. Also referred to as natural products, they have been widely applied in medicine, agriculture, cosmetic and food industries. Traditionally, the main discovery strategies have centered around the use of activity-guided fractionation of metabolite extracts. Increasingly, omics data is being used to complement this, as it has the potential to reduce rediscovery rates, guide experimental work towards the most promising metabolites, and identify enzymatic pathways that enable their biosynthetic production. In recent years, genomic and metabolomic analyses of specialized metabolic diversity have been scaled up to study thousands of samples simultaneously. Here, we survey data analysis technologies that facilitate the effective exploration of large genomic and metabolomic datasets, and discuss various emerging strategies to integrate these two types of omics data in order to further accelerate discovery
Antiangiogenic effects of coumarins against cancer: from chemistry to medicine
Angiogenesis, the process of formation and recruitment of new blood vessels from
pre-existing vessels, plays an important role in the development of cancer. Therefore, the use of
antiangiogenic agents is one of the most critical strategies for the treatment of cancer. In addition,
the complexity of cancer pathogenicity raises the need for multi-targeting agents. Coumarins are
multi-targeting natural agents belonging to the class of benzopyrones. Coumarins have several
biological and pharmacological effects, including antimicrobial, antioxidant, anti-inflammation,
anticoagulant, anxiolytic, analgesic, and anticancer properties. Several reports have shown
that the anticancer effect of coumarins and their derivatives are mediated through targeting
angiogenesis by modulating the functions of vascular endothelial growth factor as well as
vascular endothelial growth factor receptor 2, which are involved in cancer pathogenesis. In the
present review, we focus on the antiangiogenic effects of coumarins and related structure-activity
relationships with particular emphasis on cancerS
Impact of United States political sanctions on international collaborations and research in Iran
International research collaborations improve individual,
institutional and governmental capacities to respond
to health crises and inequalities but may be greatly
affected by political environments. Iran ranks highly
in tertiary education, productivity growth, knowledge
impact and successful patent applications. In many
countries, economic hardship has correlated with
increased international research collaborations. Some
have hypothesised that financial constraint drives scholars
to seek outside collaborations for cost and risk sharing,
and to access funding, materials and patient populations
otherwise unavailable. This paper explores the history
and importance of US political sanctions on the health
of Iran’s academic sector. Although Iran’s international
research collaborations increased during periods of
increased sanctions, the Pearson correlation coefficient
between gross domestic product and international
research collaborations was not significant (r=0.183,
p=0.417). This indicates that other factors are at least in
part responsible. Additionally, we found Iran’s quantitative
(eg, publication number) and qualitative (eg, visibility
indices) publishing metrics to be discordant (two-tailed
Mann–Kendall trend; p<0.0002 for both). Reasons for this
are multifactorial, including increased indexing of Iranian
journals, willingness of lower visibility journals to handle
manuscripts with Iranian authors, widespread linkage
of career advancement to science visibility indices, and
others. During periods of increased sanctions, Iranian
scholars were increasingly denied opportunities to publish
scientific findings, attend scientific meetings, access to
essential medical and laboratory supplies and information
resources. We conclude that academic boycotts violate
researchers’ freedom and curtail progress. Free exchange
of ideas irrespective of creed is needed to optimize global
scientific progress
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