Correlating Fourier phase information with real-space higher order statistics

We establish for the first time heuristic correlations between harmonic space phase information and higher order statistics. Using the spherical full-sky maps of the cosmic microwave background as an example we demonstrate that known phase correlations at large spatial scales can gradually be diminished when subtracting a suitable best-fit (Bianchi-) template map of given strength. The weaker phase correlations lead in turn to a vanishing signature of anisotropy when measuring the Minkowski functionals and scaling indices in real-space and comparing them with surrogate maps being free of phase correlations. Those investigations can open a new road to a better understanding of signatures of non-Gaussianities in complex spatial structures by elucidating the meaning of Fourier phase correlations and their influence on higher order statistics.Comment: 6 pages plus 1 supplemental page, 4 figures, submitte

Malaria Knowledge and Bed Net Use in Three Transmission Settings in Southern Africa

Background: Insecticide-treated nets (ITNs) reduce malaria morbidity and mortality in endemic areas. Despite increasing availability, the use of ITNs remains limited in some settings. Poor malaria knowledge is a barrier to the widespread use of ITNs. The goal of this study was to assess the levels of malaria knowledge and evaluate factors associated with bed net use among individuals residing in three regions of southern Africa with different levels of malaria transmission and control. Methods: A cross-sectional study was conducted on a sample of 7535 residents recruited from 2066 households in Mutasa District, Zimbabwe (seasonal malaria transmission), Choma District, Zambia (low transmission) and Nchelenge District, Zambia (high transmission), between March 2012 and March 2017. A standardized questionnaire was used to collect data on demographics, malaria-related knowledge and use of preventive measures. Multivariate logistic regression analyses were used to assess determinants of bed net use. Results: Most of the 3836 adult participants correctly linked mosquito bites to malaria (85.0%), mentioned at least one malaria symptom (95.5%) and knew of the benefit of sleeping under an ITN. Bed net ownership and use were highest in Choma and Nchelenge Districts and lowest in Mutasa District. In multivariate analyses, knowledge of ITNs was associated with a 30-40% increased likelihood of bed net use after adjusting for potential confounders across all sites. Other factors significantly associated with bed net use were age, household size and socioeconomic status, although the direction, strength and size of association varied by study site. Importantly, participants aged 5-14 years had reduced odds of sleeping under a bed net compared to children younger than 5 years. Conclusion: Relevant knowledge of ITNs translated into the expected preventive behaviour of sleeping under a bed net, underscoring the need for continued health messaging on malaria prevention. The implementation and delivery of malaria control and elimination interventions needs to consider socioeconomic equity gaps, and target school-age children to ensure access to and improve utilization of ITNs

A fast and versatile method for spectral emissivity measurement at high temperatures

International audienceIn this paper, the development of a new device for high temperature emissivity measurement is described. This device aims at measuring both spectral and total emissivity for a thermal range of 600–1000 °C. The main targeted properties of this device are versatility and simplicity. To achieve this, a rigorous selection of components such as heating systems, heat sources, sample holders, and measuring devices was made. Sample dimensions and the corresponding sample holder were optimized through a ray tracing model computation. Selection of sensors to compute the total emissivity was also discussed. A near-infrared (NIR) spectrometer and two mid-infrared (MIR) cameras equipped with optical filters covering the bandwidth of 3–5 and 7.5–13 μm were chosen for spectral measurements. The major impediment was the separation of the sample signal and various spurious signals emitted by the environment. A specific measurement methodology was then made for each bandwidth to resolve this issue. Platinum was chosen as the reference material for the device validation. Spectral emissivity measurements were then compared to values from a commercial spectrometer. A good agreement was found between NIR and MIR band I measurements, and a higher error rate was seen in MIR band II which is explained by a less favorable signal to noise ratio. Integrated emissivity is then calculated and compared to values found in the literature. A good agreement between these values is found, and similar trends with temperature are observed. The device is then validated for spectral and total emissivity measurements. Device versatility and simplicity allow for an easy adaptation to a large area of applications

Impact of the Specific Mutation in KRAS Codon 12 Mutated Tumors on Treatment Efficacy in Patients with Metastatic Colorectal Cancer Receiving Cetuximab-Based First-Line Therapy: A Pooled Analysis of Three Trials

Purpose: This study investigated the impact of specific mutations in codon 12 of the Kirsten-ras (KRAS) gene on treatment efficacy in patients with metastatic colorectal cancer (mCRC). Patients: Overall, 119 patients bearing a KRAS mutation in codon 12 were evaluated. All patients received cetuximab-based first-line chemotherapy within the Central European Cooperative Oncology Group (CECOG), AIO KRK-0104 or AIO KRK-0306 trials. Results: Patients with KRAS codon 12 mutant mCRC showed a broad range of outcome when treated with cetuximab-based first-line regimens. Patients with tumors bearing a KRAS p.G12D mutation showed a strong trend to a more favorable outcome compared to other mutations (overall survival 23.3 vs. 14-18 months; hazard ratio 0.66, range 0.43-1.03). An interaction model illustrated that KRAS p.G12C was associated with unfavorable outcome when treated with oxaliplatin plus cetuximab. Conclusion: The present analysis suggests that KRAS codon 12 mutation may not represent a homogeneous entity in mCRC when treated with cetuximab-based first-line therapy. Copyright (C) 2012 S. Karger AG, Base

Risk of bowel obstruction in patients with colon cancer responding to immunotherapy: an international case series

Background Immunotherapy is used routinely for treating deficient mismatch repair (dMMR) colon cancer (CC). This case series highlights an emerging safety issue, where patients develop bowel obstruction associated with immunotherapy response. Patients and methods Patients with dMMR CC who developed bowel obstruction while responding to immunotherapy were retrospectively identified. Data on patient, disease, treatment, and response-specific factors were explored for potential risk factors. Overall treatment numbers were used to estimate incidence. Results Nine patients from eight European centres were included. Common features were hepatic flexure location (5/9), T4 radiological staging (6/9), annular shape (8/9), radiological stricturing (5/9), and endoscopic obstruction (6/9). All received pembrolizumab and obstructed between 45 and 652 days after starting treatment. Seven patients underwent surgical resection; one was managed with a defunctioning stoma; and one was managed conservatively. One patient died from obstruction. Radiological response was seen in eight patients, including two complete responses. Pathological response was seen in all seven who underwent resection, including four complete responses. The overall incidence of immunotherapy response-related obstruction in these centres was 1.51%. Conclusions Bowel obstruction associated with immunotherapy response may represent a rare treatment-related complication in dMMR CC. Clinicians must recognise this safety signal and share experience to maintain patient safety

Measurement and Modeling of Particle Radiation in Coal Flames

This work aims at developing a methodology that can provide information of in-flame particle radiation in industrial-scale flames. The method is based on a combination of experimental and modeling work. The experiments have been performed in the high-temperature zone of a 77 kWth swirling lignite flame. Spectral radiation, total radiative intensity, gas temperature, and gas composition were measured, and the radiative intensity in the furnace was modeled with an axisymmetric cylindrical radiation model using Mie theory for the particle properties and a statistical narrow-band model for the gas properties. The in-flame particle radiation was measured with a Fourier transform infrared (FTIR) spectrometer connected to a water-cooled probe via fiber optics. In the cross-section of the flame investigated, the particles were found to be the dominating source of radiation. Apart from giving information about particle radiation and temperature, the methodology can also provide estimates of the amount of soot radiation and the maximum contribution from soot radiation compared to the total particle radiation. In the center position in the flame, the maximum contribution from soot radiation was estimated to be less than 40% of the particle radiation. As a validation of the methodology, the modeled total radiative intensity was compared to the total intensity measured with a narrow angle radiometer and the agreement in the results was good, supporting the validity of the used approach

Interaction of turbulence, chemistry, and radiation in strained nonpremixed flames

This paper provides an overview of recent progress in our development of highfidelity simulation of turbulent combustion with detailed chemistry. In particular, two major accomplishments are presented and discussed: (a) As for the computational aspects, it was recognized that many existing techniques to treat inflow and outflow boundary conditions for compressible flow simulations suffered from spurious errors when applied to highly turbulent reacting flow problems. Upon careful examination, the sources of these problems have been identified and an improved characteristic boundary condition strategy has been developed. The new method has been applied to various test problems, thereby demonstrating that the improved boundary conditions can successfully reproduce complex combustion events in a finite domain size with desired accuracy and stability. (b) As a science application, more advanced physical models for soot formation and radiative heat transfer have been developed in order to provide fundamental understanding of the interaction among turbulence, chemistry and radiation. We have performed several parametric simulations of two-dimensional ethyleneair nonpremixed counterflow flames interacting with counter-rotating vortex pairs and injected turbulent flows to investigate transient dynamics of soot formation process. Detailed analysis on the transient characteristics of soot behavior is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49003/2/jpconf5_16_011.pd

Intravascular Ultrasound (IVUS): A Potential Arthroscopic Tool for Quantitative Assessment of Articular Cartilage

Conventional ultrasound examination of the articular cartilage performed externally on the body surface around the joint has limited accuracy due to the inadequacy in frequency used. In contrast to this, minimally invasive arthroscopy-based ultrasound with adequately high frequency may be a better alternative to assess the cartilage. Up to date, no special ultrasound transducer for imaging the cartilage in arthroscopic use has been designed. In this study, we introduced the intravascular ultrasound (IVUS) for this purpose. An IVUS system with a catheter-based probe (Ø ≈ 1mm) was used to measure the thickness and surface acoustical reflection of the bovine patellar articular cartilage in vitro before and after degeneration induced by enzyme treatments. Similar measurement was performed using another high frequency ultrasound system (Vevo) with a probe of much larger size and the results were compared between the two systems. The thickness measured using IVUS was highly correlated (r = 0.985, p < 0.001) with that obtained by Vevo. Thickness and surface reflection amplitude measured using IVUS on the enzymatically digested articular cartilage showed changes similar to those obtained by Vevo, which were expectedly consistent with previous investigations. IVUS can be potentially used for the quantitative assessment of articular cartilage, with its ready-to-use arthroscopic feature