Laplacian spectral characterization of roses

A rose graph is a graph consisting of cycles that all meet in one vertex. We show that except for two specific examples, these rose graphs are determined by the Laplacian spectrum, thus proving a conjecture posed by Lui and Huang [F.J. Liu and Q.X. Huang, Laplacian spectral characterization of 3-rose graphs, Linear Algebra Appl. 439 (2013), 2914--2920]. We also show that if two rose graphs have a so-called universal Laplacian matrix with the same spectrum, then they must be isomorphic. In memory of Horst Sachs (1927-2016), we show the specific case of the latter result for the adjacency matrix by using Sachs' theorem and a new result on the number of matchings in the disjoint union of paths

Combustion Dynamics Characteristics and Fuel Pressure Modulation Responses of a Three-Cup Third-Generation Swirl-Venturi Lean Direct Injection Combustion Concept

This paper presents the combustion dynamic data and fuel modulation response of a three-cup Lean Direct Injection combustor developed by Woodward, FST. The test was conducted at the NASA Glenn Research Center CE-5 flame tube test facility. The facility provided inlet air up to 922 K and pressure up to 19.0 bar. At the low-power configuration, the combustion noise was quiet. Large combustion pressure oscillations were observed with the High-power configuration at an off design condition, with low inlet air temperature and pressure conditions and a high equivalence ratio (about T3=600 K, P3 = 800 kPa, and ER =0.46). The noise amplitude was as high as 1.5 psi at around 220 Hz. As inlet air pressure and temperature increased, this combustion instability decreased. Fuel modulated signals were produced with the WASK fuel modulator located in the fuel line upstream of the center cup pilot fuel-air mixer. The amplitudes of the modulated signals detected in the combustor were low. Only less than 0.13% (0.06 psi) of the input energy was detected, and the signal amplitudes decreased as the modulated frequencies increased. Interaction between the modulated signals and the combustion noise varied with operating conditions. At a condition with low combustion noise around 150 hz, modulating a signal at around the same frequency would increase the combustion noise from 0.2 psi to as high as 0.6 psi, whereas at a condition with a high combustion instability around 250 hz, the modulated signal did not seem to have much effect on the combustion noise

Dietary Patterns and Glucose Tolerance Abnormalities in Chinese Adults

OBJECTIVE To investigate the association of the dietary pattern with the presence of newly diagnosed glucose tolerance abnormalities among Chinese adults. RESEARCH DESIGN AND METHODS A total of 20,210 adults aged 45–69 years from the 2002 China National Nutrition and Health Survey were included. Information on dietary intake was collected using a validated food frequency questionnaire. Factor analysis and cluster analysis were used to identify the food factors and dietary pattern clusters. RESULTS Four dietary pattern clusters were identified (“Green Water,” “Yellow Earth,” “Western Adopter,” and “New Affluence”). The prevalence of glucose tolerance abnormalities ranged from 3.9% in the Green Water to 8.0% in the New Affluence. After adjustment for area, age, sex, current smoking, and physical activity, subjects in the Yellow Earth cluster (prevalence ratio 1.22 [95% CI 1.04–1.43]) and New Affluence cluster (2.05 [1.76–2.37]) had significantly higher prevalence rates compared with those for the Green Water cluster. After further adjustment for BMI and waist-to-height ratio, the elevated risk in the New Affluence remained statistically significant. CONCLUSIONS Dietary patterns and food factors are associated with the presence of glucose tolerance abnormalities in China, even independent of obesity. A New Affluence diet is an important modifiable risk factor, which needs attention from the prevention point of vie

A Second Generation Swirl-Venturi Lean Direct Injection Combustion Concept

A low-NO (sub x) aircraft gas turbine engine combustion concept was developed and tested. The concept is a second generation swirl-venturi lean direct injection (SV-LDI) concept. LDI is a lean-burn combustion concept in which the fuel is injected directly into the flame zone. Three second generation SV-LDI configurations were developed. All three were based on the baseline 9-point SV-LDI configuration reported previously. These second generation configurations had better low power operability than the baseline 9-point configuration. Two of these second generation configurations were tested in a NASA Glenn Research Center flametube; these two configurations are called the at dome and 5-recess configurations. Results show that the 5-recess configuration generally had lower NO (sub x) emissions than the flat dome configuration. Correlation equations were developed for the flat dome configuration so that the landing-takeoff NO (sub x) emissions could be estimated. The flat dome landing-takeoff NO (sub x) is estimated to be 87-88 percent below the CAEP/6 standards, exceeding the ERA project goal of 75 percent reduction

Classically and alternatively activated bone marrow derived macrophages differ in cytoskeletal functions and migration towards specific CNS cell types

<p>Abstract</p> <p>Background</p> <p>Macrophages play an important role in neuroinflammatory diseases such as multiple sclerosis (MS) and spinal cord injury (SCI), being involved in both damage and repair. The divergent effects of macrophages might be explained by their different activation status: classically activated (CA/M1), pro-inflammatory, macrophages and alternatively activated (AA/M2), growth promoting, macrophages. Little is known about the effect of macrophages with these phenotypes in the central nervous system (CNS) and how they influence pathogenesis. The aim of this study was therefore to determine the characteristics of these phenotypically different macrophages in the context of the CNS in an <it>in vitro </it>setting.</p> <p>Results</p> <p>Here we show that bone marrow derived CA and AA macrophages have a distinct migratory capacity towards medium conditioned by various cell types of the CNS. AA macrophages were preferentially attracted by the low weight (< 10 kD) fraction of neuronal conditioned medium, while CA macrophages were attracted in higher numbers by astrocyte- and oligodendrocyte conditioned medium. Intrinsic motility was twice as high in AA macrophages compared to CA macrophages. The adhesion to extracellular matrix molecules (ECM) was significantly enhanced in CA macrophages compared to control and AA macrophages. The actin cytoskeleton was differentially organized between CA and AA macrophages, possibly due to greater activity of the GTPases RhoA and Rac in CA macrophages. Phagocytosis of myelin and neuronal fragments was increased in CA macrophages compared to AA macrophages. The increase in myelin phagocytosis was associated with higher expression of CR3/MAC-1 in CA macrophages.</p> <p>Conclusion</p> <p>In conclusion, since AA macrophages are more motile and are attracted by NCM, they are prone to migrate towards neurons in the CNS. CA macrophages have a lower motility and a stronger adhesion to ECM. In neuroinflammatory diseases the restricted migration and motility of CA macrophages might limit lesion size due to bystander damage.</p

A nomogram to predict the probability of axillary lymph node metastasis in early breast cancer patients with positive axillary ultrasound

Among patients with a preoperative positive axillary ultrasound, around 40% of them are pathologically proved to be free from axillary lymph node (ALN) metastasis. We aimed to develop and validate a model to predict the probability of ALN metastasis as a preoperative tool to support clinical decision-making. Clinicopathological features of 322 early breast cancer patients with positive axillary ultrasound findings were analyzed. Multivariate logistic regression analysis was performed to identify independent predictors of ALN metastasis. A model was created from the logistic regression analysis, comprising lymph node transverse diameter, cortex thickness, hilum status, clinical tumour size, histological grade and estrogen receptor, and it was subsequently validated in another 234 patients. Coefficient of determination (R-2) and the area under the ROC curve (AUC) were calculated to be 0.9375 and 0.864, showing good calibration and discrimination of the model, respectively. The false-negative rates of the model were 0% and 5.3% for the predicted probability cut-off points of 7.1% and 13.8%, respectively. This means that omission of axillary surgery may be safe for patients with a predictive probability of less than 13.8%. After further validation in clinical practice, this model may support increasingly limited surgical approaches to the axilla in breast cancer

Unitarity bounds on low scale quantum gravity

We study the unitarity of models with low scale quantum gravity both in four dimensions and in models with a large extra-dimensional volume. We find that models with low scale quantum gravity have problems with unitarity below the scale at which gravity becomes strong. An important consequence of our work is that their first signal at the Large Hadron Collider would not be of a gravitational nature such as graviton emission or small black holes, but rather linked to the mechanism which fixes the unitarity problem. We also study models with scalar fields with non minimal couplings to the Ricci scalar. We consider the strength of gravity in these models and study the consequences for inflation models with non-minimally coupled scalar fields. We show that a single scalar field with a large non-minimal coupling can lower the Planck mass in the TeV region. In that model, it is possible to lower the scale at which gravity becomes strong down to 14 TeV without violating unitarity below that scale.Comment: 15 page

An Extended Fourier Approach to Improve the Retrieved Leaf Area Index (LAI) in a Time Series from an Alpine Wetland

An extended Fourier approach was presented to improve the retrieved leaf area index (LAIr) of herbaceous vegetation in a time series from an alpine wetland. The retrieval was performed from the Aqua MODIS 8-day composite surface reflectance product (MYD09Q1) from day of year (DOY) 97 to 297 using a look-up table (LUT) based inversion of a two-layer canopy reflectance model (ACRM). To reduce the uncertainty (the ACRM inversion is ill-posed), we used NDVI and NIR images to reduce the influence of the soil background and the priori information to constrain the range of sensitive ACRM parameters determined using the Sobol’s method. Even so the uncertainty caused the LAIr versus time curve to oscillate. To further reduce the uncertainty, a Fourier model was fitted using the periodically LAIr results, obtaining LAIF. We note that the level of precision of the LAIF potentially may increase through removing singular points or decrease if the LAIr data were too noisy. To further improve the precision level of the LAIr, the Fourier model was extended by considering the LAIr uncertainty. The LAIr, the LAI simulated using the Fourier model, and the LAI simulated using the extended Fourier approach (LAIeF) were validated through comparisons with the field measured LAI. The R2 values were 0.68, 0.67 and 0.72, the residual sums of squares (RSS) were 3.47, 3.42 and 3.15, and the root-mean-square errors (RMSE) were 0.31, 0.30 and 0.29, respectively, on DOY 177 (early July 2011). In late August (DOY 233), the R2 values were 0.73, 0.77 and 0.79, the RSS values were 38.96, 29.25 and 27.48, and the RMSE values were 0.94, 0.81 and 0.78, respectively. The results OPEN ACCESS Remote Sens. 2014, 6 1172 demonstrate that the extended Fourier approach has the potential to increase the level of precision of estimates of the time varying LAI