2,548 research outputs found
Aircraft route forecasting under adverse weather conditions
In this paper storm nowcasts in the terminal manoeuvring area (TMA) of Hong Kong International Airport are used to forecast deviation routes through a field of storms for arriving and departing aircraft. Storms were observed and nowcast by the nowcast system SWIRLS from the Hong Kong Observatory. Storms were considered as no-go zones for aircraft and deviation routes were determined with the DIVSIM software package. Two days (21 and 22 May 2011) with 22 actual flown routes were investigated. Flights were simulated with a nowcast issued at the time an aircraft entered the TMA or departed from the airport. These flights were compared with a posteriori simulations, in which all storm fields were known and circumnavigated. Both types of simulated routes were then compared with the actual flown routes. The qualitative comparison of the various routes revealed generally good agreement. Larger differences were found in more complex situations with many active storms in the TMA. Route differences resulted primarily from air traffic control measures imposed such as holdings, slow-downs and shortcuts, causing the largest differences between the estimated and actual landing time. Route differences could be enhanced as aircraft might be forced to circumnavigate a storm ahead in a different sense. The use of route forecasts to assist controllers coordinating flights in a complex moving storm field is discussed. The study emphasises the important application of storm nowcasts in aviation meteorology
Smectic ordering in liquid crystal - aerosil dispersions II. Scaling analysis
Liquid crystals offer many unique opportunities to study various phase
transitions with continuous symmetry in the presence of quenched random
disorder (QRD). The QRD arises from the presence of porous solids in the form
of a random gel network. Experimental and theoretical work support the view
that for fixed (static) inclusions, quasi-long-range smectic order is destroyed
for arbitrarily small volume fractions of the solid. However, the presence of
porous solids indicates that finite-size effects could play some role in
limiting long-range order. In an earlier work, the nematic - smectic-A
transition region of octylcyanobiphenyl (8CB) and silica aerosils was
investigated calorimetrically. A detailed x-ray study of this system is
presented in the preceding Paper I, which indicates that pseudo-critical
scaling behavior is observed. In the present paper, the role of finite-size
scaling and two-scale universality aspects of the 8CB+aerosil system are
presented and the dependence of the QRD strength on the aerosil density is
discussed.Comment: 14 pages, 10 figures, 1 table. Companion paper to "Smectic ordering
in liquid crystal - aerosil dispersions I. X-ray scattering" by R.L. Leheny,
S. Park, R.J. Birgeneau, J.-L. Gallani, C.W. Garland, and G.S. Iannacchion
Recommended from our members
Combined burden and functional impact tests for cancer driver discovery using DriverPower
The discovery of driver mutations is one of the key motivations for cancer genome sequencing. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2658 cancers across 38 tumour types, we describe DriverPower, a software package that uses mutational burden and functional impact evidence to identify driver mutations in coding and non-coding sites within cancer whole genomes. Using a total of 1373 genomic features derived from public sources, DriverPower's background mutation model explains up to 93% of the regional variance in the mutation rate across multiple tumour types. By incorporating functional impact scores, we are able to further increase the accuracy of driver discovery. Testing across a collection of 2583 cancer genomes from the PCAWG project, DriverPower identifies 217 coding and 95 non-coding driver candidates. Comparing to six published methods used by the PCAWG Drivers and Functional Interpretation Working Group, DriverPower has the highest F1 score for both coding and non-coding driver discovery. This demonstrates that DriverPower is an effective framework for computational driver discovery
Chlamydia infections of the eye and the use of copper sulphate for the symptomatic relief of trachoma
Chlamydia trachomatis is responsible for two of the most prevalent infectious eye diseases in the world today, trachoma and inclusion conjunctivitis. Trachoma is still the leading cause of preventable blindness in the Third World and the incidence of inclusion conjunctivitis is on the in the industrialized world. Both ocular infections have been reviewed. This paper investigates a unique treatment regimen for the subjective symptoms of trachoma utilized in many practices in Southeast Asia. The data was gathered from one particular ophthalmological practice in Hong Kong. The procedure uses copper sulphate crystals 1n conjunction with conventional antibiotic therapy for patients with moderate to severe symptoms. For severe cases, topical dexamethasone is added to the treatment regimen. Ninety-one files of patients who underwent this mode of treatment were randomly selected from the Hong Kong practice and were described according to distribution of age, phase of treatment, and length of treatment. A survey of these patients revealed a significant percentage (75%) of satisfaction and relief of symptoms. We propose that copper sulphate should be considered for similar use with inclusion conjunctivitis to accelerate the relief of ocular symptomology
CLASS: The Cosmology Large Angular Scale Surveyor
The Cosmology Large Angular Scale Surveyor (CLASS) is an experiment to
measure the signature of a gravita-tional-wave background from inflation in the
polarization of the cosmic microwave background (CMB). CLASS is a
multi-frequency array of four telescopes operating from a high-altitude site in
the Atacama Desert in Chile. CLASS will survey 70\% of the sky in four
frequency bands centered at 38, 93, 148, and 217 GHz, which are chosen to
straddle the Galactic-foreground minimum while avoiding strong atmospheric
emission lines. This broad frequency coverage ensures that CLASS can
distinguish Galactic emission from the CMB. The sky fraction of the CLASS
survey will allow the full shape of the primordial B-mode power spectrum to be
characterized, including the signal from reionization at low . Its unique
combination of large sky coverage, control of systematic errors, and high
sensitivity will allow CLASS to measure or place upper limits on the
tensor-to-scalar ratio at a level of and make a
cosmic-variance-limited measurement of the optical depth to the surface of last
scattering, .Comment: 23 pages, 10 figures, Presented at SPIE Astronomical Telescopes and
Instrumentation 2014: Millimeter, Submillimeter, and Far-Infrared Detectors
and Instrumentation for Astronomy VII. To be published in Proceedings of SPIE
Volume 915
Embracing assay heterogeneity with neural processes for markedly improved bioactivity predictions
Predicting the bioactivity of a ligand is one of the hardest and most
important challenges in computer-aided drug discovery. Despite years of data
collection and curation efforts by research organizations worldwide,
bioactivity data remains sparse and heterogeneous, thus hampering efforts to
build predictive models that are accurate, transferable and robust. The
intrinsic variability of the experimental data is further compounded by data
aggregation practices that neglect heterogeneity to overcome sparsity. Here we
discuss the limitations of these practices and present a hierarchical
meta-learning framework that exploits the information synergy across disparate
assays by successfully accounting for assay heterogeneity. We show that the
model achieves a drastic improvement in affinity prediction across diverse
protein targets and assay types compared to conventional baselines. It can
quickly adapt to new target contexts using very few observations, thus enabling
large-scale virtual screening in early-phase drug discovery
BRCA2 polymorphic stop codon K3326X and the risk of breast, prostate, and ovarian cancers
Background: The K3326X variant in BRCA2 (BRCA2*c.9976A>T; p.Lys3326*; rs11571833) has been found to be associated with small increased risks of breast cancer. However, it is not clear to what extent linkage disequilibrium with fully pathogenic mutations might account for this association. There is scant information about the effect of K3326X in other hormone-related cancers.
Methods: Using weighted logistic regression, we analyzed data from the large iCOGS study including 76 637 cancer case patients and 83 796 control patients to estimate odds ratios (ORw) and 95% confidence intervals (CIs) for K3326X variant carriers in relation to breast, ovarian, and prostate cancer risks, with weights defined as probability of not having a pathogenic BRCA2 variant. Using Cox proportional hazards modeling, we also examined the associations of K3326X with breast and ovarian cancer risks among 7183 BRCA1 variant carriers. All statistical tests were two-sided.
Results: The K3326X variant was associated with breast (ORw = 1.28, 95% CI = 1.17 to 1.40, P = 5.9x10- 6) and invasive ovarian cancer (ORw = 1.26, 95% CI = 1.10 to 1.43, P = 3.8x10-3). These associations were stronger for serous ovarian cancer and for estrogen receptor–negative breast cancer (ORw = 1.46, 95% CI = 1.2 to 1.70, P = 3.4x10-5 and ORw = 1.50, 95% CI = 1.28 to 1.76, P = 4.1x10-5, respectively). For BRCA1 mutation carriers, there was a statistically significant inverse association of the K3326X variant with risk of ovarian cancer (HR = 0.43, 95% CI = 0.22 to 0.84, P = .013) but no association with breast cancer. No association with prostate cancer was observed.
Conclusions: Our study provides evidence that the K3326X variant is associated with risk of developing breast and ovarian cancers independent of other pathogenic variants in BRCA2. Further studies are needed to determine the biological mechanism of action responsible for these associations
Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas
This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing
molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
- …
