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Is hazard perception ability culturally specific? A cross-cultural comparison between China, Spain and the UK
Hazard perception refers to a driver’s ability to spot hazards on the road in time to make a safe manoeuvre to avoid collision. Such a test is now part of the formal licencing procedure in the UK and in parts of Australia. But can such tests be successfully exported to other countries to reduce traffic fatalities?
The aim of this project is to study whether hazard perception skill is culturally specific by comparing UK, Spanish and Chinese drivers across clips filmed in all three countries. Data collection was set-up in the respective countries in collaboration with the University of Granada (Spain) and Tsinghua University (China). Participants had to watch 30 video clips filmed from the driver’s perspective (10 filmed in each of the three countries). Two variants of the test were created: a typical hazard perception test (with full clips requiring speeded responses to hazards), and a hazard prediction task (or 'What Happens Next?' task), where the film ends immediately prior to the hazard onset. This latter test removes the confound of individual hazard thresholds, as participants could successfully report 'what happens next' without judging whether it posed a hazard to them. All videos contained a variety of hazardous situations (or precursors to hazards) reflecting the particular driving environment of each country.
Three hundred participants across the 3 countries were tested, evenly divided between learner and experienced drivers. The differences between the culturally-specific tests in their ability to discriminate between driver groups will be discussed in regards to the potential for employing hazard perception testing in diverse geographical locations and cultures
Diesel Exhaust Particles Activate the Matrix-Metalloproteinase-1 Gene in Human Bronchial Epithelia in a β-Arrestin–Dependent Manner via Activation of RAS
BACKGROUND: Diesel exhaust particles (DEPs) are globally relevant air pollutants that exert a detrimental human health impact. However, mechanisms of damage by DEP exposure to human respiratory health and human susceptibility factors are only partially known. Matrix metalloproteinase-1 (MMP-1) has been implied as an (etio)pathogenic factor in human lung and airway diseases such as emphysema, chronic obstructive pulmonary disease, chronic asthma, tuberculosis, and bronchial carcinoma and has been reported to be regulated by DEPs. OBJECTIVE: We elucidated the molecular mechanisms of DEPs' up-regulation of MMP-1. METHODS/RESULTS: Using permanent and primary human bronchial epithelial (HBE) cells at air-liquid interface, we show that DEPs activate the human MMP-1 gene via RAS and subsequent activation of RAF-MEK-ERK1/2 mitogen-activated protein kinase signaling, which can be scaffolded by beta-arrestins. Short interfering RNA mediated beta-arrestin1/2 knockout eliminated formation, subsequent nuclear trafficking of phosphorylated ERK1/2, and resulting MMP-1 transcriptional activation. Transcriptional regulation of the human MMP-1 promoter was strongly influenced by the presence of the -1607GG polymorphism, present in 60-80% of humans, which led to striking up-regulation of MMP-1 transcriptional activation. CONCLUSION: Our results confirm up-regulation of MMP-1 in response to DEPs in HBE and provide new mechanistic insight into how these epithelia, the first line of protection against environmental insults, up-regulate MMP-1 in response to DEP inhalation. These mechanisms include a role for the human -1607GG polymorphism as a susceptibility factor for an accentuated response, which critically depends on the ability of beta-arrestin1/2 to generate scaffolding and nuclear trafficking of phosphorylated ERK1/2
QCD corrections to plus -boson production at the LHC
The associated production at the LHC is an important process in
investigating the color-octet mechanism of non-relativistic QCD in describing
the processes involving heavy quarkonium. We calculate the next-to-leading
order (NLO) QCD corrections to the associated production at the
LHC within the factorization formalism of nonrelativistic QCD, and provide the
theoretical predictions for the distribution of the transverse
momentum. Our results show that the differential cross section at the
leading-order is significantly enhanced by the NLO QCD corrections. We conclude
that the LHC has the potential to verify the color-octet mechanism by measuring
the production events.Comment: 14 page revtex, 5 eps figures, to appear in JHEP. fig5 and the
corresponding analysis are correcte
The genome and transcriptome of Trichormus sp NMC-1: insights into adaptation to extreme environments on the Qinghai-Tibet Plateau
The Qinghai-Tibet Plateau (QTP) has the highest biodiversity for an extreme environment worldwide, and provides an ideal natural laboratory to study adaptive evolution. In this study, we generated a draft genome sequence of cyanobacteria Trichormus sp. NMC-1 in the QTP and performed whole transcriptome sequencing under low temperature to investigate the genetic mechanism by which T. sp. NMC-1 adapted to the specific environment. Its genome sequence was 5.9 Mb with a G+C content of 39.2% and encompassed a total of 5362 CDS. A phylogenomic tree indicated that this strain belongs to the Trichormus and Anabaena cluster. Genome comparison between T. sp. NMC-1 and six relatives showed that functionally unknown genes occupied a much higher proportion (28.12%) of the T. sp. NMC-1 genome. In addition, functions of specific, significant positively selected, expanded orthogroups, and differentially expressed genes involved in signal transduction, cell wall/membrane biogenesis, secondary metabolite biosynthesis, and energy production and conversion were analyzed to elucidate specific adaptation traits. Further analyses showed that the CheY-like genes, extracellular polysaccharide and mycosporine-like amino acids might play major roles in adaptation to harsh environments. Our findings indicate that sophisticated genetic mechanisms are involved in cyanobacterial adaptation to the extreme environment of the QTP
A Terminal Velocity on the Landscape: Particle Production near Extra Species Loci in Higher Dimensions
We investigate particle production near extra species loci (ESL) in a higher
dimensional field space and derive a speed limit in moduli space at weak
coupling. This terminal velocity is set by the characteristic ESL-separation
and the coupling of the extra degrees of freedom to the moduli, but it is
independent of the moduli's potential if the dimensionality of the field space
is considerably larger than the dimensionality of the loci, D >> d. Once the
terminal velocity is approached, particles are produced at a plethora of nearby
ESLs, preventing a further increase in speed via their backreaction. It is
possible to drive inflation at the terminal velocity, providing a
generalization of trapped inflation with attractive features: we find that more
than sixty e-folds of inflation for sub-Planckian excursions in field space are
possible if ESLs are ubiquitous, without fine tuning of initial conditions and
less tuned potentials. We construct a simple, observationally viable model with
a slightly red scalar power-spectrum and suppressed gravitational waves; we
comment on the presence of additional observational signatures originating from
IR-cascading and individual massive particles. We also show that
moduli-trapping at an ESL is suppressed for D >> d, hindering dynamical
selection of high-symmetry vacua on the landscape based on this mechanism.Comment: 46 pages, 6 figures. V3: typos corrected compared to JHEP version,
conclusions unchange
Recent changes of water discharge and sediment load in the Yellow River basin, China
The Yellow River basin contributes approximately 6% of the sediment load from all river systems globally, and the annual runoff directly supports 12% of the Chinese population. As a result, describing and understanding recent variations of water discharge and sediment load under global change scenarios are of considerable importance. The present study considers the annual hydrologic series of the water discharge and sediment load of the Yellow River basin obtained from 15 gauging stations (10 mainstream, 5 tributaries). The Mann-Kendall test method was adopted to detect both gradual and abrupt change of hydrological series since the 1950s. With the exception of the area draining to the Upper Tangnaihai station, results indicate that both water discharge and sediment load have decreased significantly (p<0.05). The declining trend is greater with distance downstream, and drainage area has a significant positive effect on the rate of decline. It is suggested that the abrupt change of the water discharge from the late 1980s to the early 1990s arose from human extraction, and that the abrupt change in sediment load was linked to disturbance from reservoir construction.Geography, PhysicalGeosciences, MultidisciplinarySCI(E)43ARTICLE4541-5613
One-dimensional Topological Edge States of Bismuth Bilayers
The hallmark of a time-reversal symmetry protected topologically insulating
state of matter in two-dimensions (2D) is the existence of chiral edge modes
propagating along the perimeter of the system. To date, evidence for such
electronic modes has come from experiments on semiconducting heterostructures
in the topological phase which showed approximately quantized values of the
overall conductance as well as edge-dominated current flow. However, there have
not been any spectroscopic measurements to demonstrate the one-dimensional (1D)
nature of the edge modes. Among the first systems predicted to be a 2D
topological insulator are bilayers of bismuth (Bi) and there have been recent
experimental indications of possible topological boundary states at their
edges. However, the experiments on such bilayers suffered from irregular
structure of their edges or the coupling of the edge states to substrate's bulk
states. Here we report scanning tunneling microscopy (STM) experiments which
show that a subset of the predicted Bi-bilayers' edge states are decoupled from
states of Bi substrate and provide direct spectroscopic evidence of their 1D
nature. Moreover, by visualizing the quantum interference of edge mode
quasi-particles in confined geometries, we demonstrate their remarkable
coherent propagation along the edge with scattering properties that are
consistent with strong suppression of backscattering as predicted for the
propagating topological edge states.Comment: 15 pages, 5 figures, and supplementary materia
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A comparison of hazard perception and hazard prediction tests across China, Spain and the UK
Hazard perception (HP) is the ability to spot on-road hazards in time to avoid a collision. This skill is traditionally measured by recording response times to hazards in video clips of driving, with safer, experienced drivers often out-performing inexperienced drivers. This study assessed whether HP test performance is culturally specific by comparing Chinese, Spanish and UK drivers who watched clips filmed in all three countries. Two test-variants were created: a traditional HP test (requiring timed hazard responses), and a hazard prediction test, where the film is occluded at hazard-onset and participants predict what happens next. More than 300 participants, across the 3 countries, were divided into experienced and inexperienced-driver groups. The traditional HP test did not discriminate between experienced and inexperienced drivers, though participant nationality influenced the results with UK drivers reporting more hazards than Chinese drivers. The hazard prediction test, however, found experienced drivers to out-perform inexperienced drivers. No differences were found for nationality, with all nationalities being equally skilled at predicting hazards. The results suggest that drivers’ criterion level for responding to hazards is culturally sensitive, though their ability to predict hazards is not. We argue that the more robust, culturally-agnostic, hazard prediction test appears better suited for global export
Effect of hypoxia-inducible factor-1α on transcription of survivin in non-small cell lung cancer
<p>Abstract</p> <p>Background</p> <p>Survivin is a structurally and functionally unique member of the inhibitor of apoptosis protein (IAP) family. It plays an important role, not only in regulating mitosis but also in inhibiting apoptosis. The current literature contains few reports on the transcriptional regulation of survivin expression in lung cancer.</p> <p>Methods</p> <p>In this study, we investigated the effect of hypoxia-inducible factor-1α (HIF-1α) on the transcriptional activity of the survivin promoter in non-small cell lung cancer (NSCLC). Immunohistochemical staining was used to detect the expression of survivin and HIF-1α in the lung tissue of 120 patients with non-small cell lung cancer (NSCLC) and 40 patients with benign pulmonary disease. We also performed experiments with the lung adenocarcinoma cell line A549 cells, which were cultured under hypoxic conditions. The expression of survivin and HIF-1α was detected by real-time RT-PCR and Western blotting. In the survivin promoter the putative binding-site for HIF-1α, is -19 bp~-16 bp upstream of TSS. We performed site-directed mutagenesis of this binding site, and used luciferase reporter plasmids to determine the relative activity of the survivin promoter in A549 cells. We also studied the effect of HIF-1α on the expression of survivin by dsRNA targeting of HIF-1α mRNA.</p> <p>Results</p> <p>HIF-1α (58.33%) and survivin (81.60%) were both over-expressed in NSCLC and their expressions correlated with one another. They were also expressed in A549 cells under normal and hypoxic conditions, with a significant increase under hypoxic conditions. Site directed mutagenesis of the putative binding site for HIF-1α in the survivin promoter significantly decreased the activity of the survivin promoter in A549 cells. Inhibition of HIF-1α by RNAi decreased the expression of survivin in A549 cell lines.</p> <p>Conclusion</p> <p>Our results indicate that the binding of HIF-1α to the survivin promoter increases transcription of the survivin gene. Thus, HIF-1α is an important transcriptional regulator of survivin expression</p
The All-Data-Based Evolutionary Hypothesis of Ciliated Protists with a Revised Classification of the Phylum Ciliophora (Eukaryota, Alveolata)
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