This study tests the hypothesis that an analytically estimated driver reaction time required for asymptotic stability, based on the macroscopic Gazis-Herman-Rothery (GHR) model, serves as an ...indicator of the impact of traffic oscillations on rear-end crashes. If separate GHR models are fit discontinuously for different traffic regimes, the local drop in required reaction time between these regimes can also be estimated. This study evaluates the relationship between rear-end crash rates and that drop in required reaction time. Traffic data from 28 sensors were used to fit the GHR model. Rear-end crash rates, estimated from four years of crash data, exhibited a positive correlation with the drop in required reaction time at the congested regime's density-breakpoint. A linear relationship provided the best fit. These results motivate follow-on research to incorporate macroscopically derived reaction time in road-safety planning. More generally, the study demonstrates a useful application of a discontinuous macroscopic traffic model.
Silicone rubber filled with micron-alumina trihydrate (ATH) is a substantially used composite material for high voltage outdoor insulators. This article investigates the effect of nano-boron nitride ...(BN) addition on the dielectric, thermal stability and thermal conductivity of solely micron-ATH-filled silicone rubber by fabricating coalesced network of particles. Micron-ATH/nano-BN-filled hybrid silicone rubber composites are fabricated with a ratio of 30/0 wt% (ATH30), 29/1 wt% (ATBN1), 27/3 wt% (ATBN3), 25/5 wt% (ATBN5) and 23/7 wt% (ATBN7) using mechanical mixing and water bath sonication techniques. Results suggest that the hybrid batch of silicone rubber composites (ATBN) possess lower permittivity, dielectric loss, enhanced thermal stability and thermal conductivity relative to ATH30. ATBN1 offers low permittivity and dielectric loss values of 3.64 and 0.0086 at 1000 Hz relative to 3.87 and 0.0224 of ATH30, respectively. As far as thermal properties are concerned, ATBN5 emerges as the most promising candidate for electrical insulation with 31 and 200°C higher temperatures for 10 and 15% mass loss, whilst it has shown 20% higher thermal conductivity than ATH30.
Background
There are no reports about the association of angiotensin II type 2 receptor (AT2R) gene polymorphisms and susceptibility to systemic lupus erythematosus (SLE) in children.
Objective
The ...objective of this research is to study AT2R gene polymorphisms in exon 3 (C1593A) and intron 1 (A1675G) in Egyptian children with SLE and its correlation with disease manifestations and serum angiotensin-converting enzyme (ACE) level.
Methods
Typing of AT2R gene polymorphisms was conducted in 123 children with SLE in comparison with 100 healthy controls using the restriction fragment length polymorphism method.
Results
Significant differences were found between SLE patients and controls for A-containing genotypes (CA + AA) and A-allele frequencies of AT2R in exon 3 (C1593A) (p = 0.01, odds ratio (OR) = 2.5, 95% confidence interval (CI) = 1.3–5.05; p = 0.01, OR = 2.2, 95% CI = 1.2–4.1, respectively). G-containing genotypes (AG + GG) and G allele of AT2R in intron 1 (A1675G) were more frequent in SLE patients compared to controls (p = 0.01, OR = 2.3, 95% CI = 1.2–4.5; p = 0.02, OR = 2.1, 95% CI = 1.2–3.7, respectively). Serum ACE level was significantly higher in SLE patients than in controls (p < 0.001). There was no association between AT2R gene polymorphisms and ACE level in serum. Moreover, there was no association between AT2R gene polymorphisms and SLE clinical manifestations.
Conclusion
AT2R gene polymorphisms can be considered risk factors for SLE development in Egyptian children.
Regional flood frequency analysis (RFFA) is used to estimate design floods in ungauged and data poor gauged catchments, which involves the transfer of flood characteristics from gauged to ungauged ...catchments. In Australia, RFFA methods have focused on the application of empirical methods based on linear forms of traditional models such as the probabilistic rational method, the index flood method and the quantile regression technique (QRT). In contrast to these traditional linear-models, non-linear methods such as artificial neural networks (ANNs) and gene expression programming (GEP) can be applied to RFFA problems. The particular advantage of these techniques is that they do not impose a model structure on the data, and they can better deal with non-linearity of the input and output relationship in regional flood modelling. These non-linear techniques have been applied successfully in a wide range of hydrological problems; however, there have been only limited applications of these techniques in RFFA problems, particularly in Australia. This paper focuses on the development and testing of the ANNs and GEP based RFFA models for eastern parts of Australia. This involves relating flood quantiles to catchment characteristics so that the developed prediction models can be used to estimate design floods in ungauged site. A data set comprising of 452 stations from eastern Australia was used to develop the new RFFA models. An independent testing shows that the non-linear methods are quite successful in RFFA and can be used as an alternative method to the more traditional approaches currently used in eastern Australia. The results based on ANN and GEP-based RFFA techniques have been found to outperform the ordinary least squares based QRT (linear technique).
We study energy transfer, Photo and X-ray luminescence in lithium barium borate glasses doped with Gd and Dy. We find that the Dy3+ luminescence at 575-nm emission wavelength increases while the Gd3+ ...emission at λem = 312 nm decreases, attributed to the energy transfer (ET) from the 6P7/2 state of Gd3+ ions to the 4F9/2 state of Dy3+ ions. From the 6P7/2 state decay lifetime (λexc = 275 nm and λem = 312 nm) of Gd3+ and that of the 4F9/2 state (λexc = 382 nm and λem = 575 nm) of the Dy3+, we compute the key parameters such as ET efficiencies, transfer probabilities and average donor-acceptor distance. Photometric parameters of the developed samples at λexc = 275 nm are calculated. Suggested by the Commission International deI’Eclairage coordinates, we infer that at 275-nm excitation, our optimized sample, LGBaB1.5Dy, produces white light. Measured from X-ray luminescence, the integral scintillation efficiency of LGBaB1.5Dy is 11%.
•Synthesized Li2O–BaO –B2O3 glasses with Gd3+ as sensitizer and Dy3+ as activator via melt quenching technique.•PL emission spectra showed boosted Dy3+ and reduced Gd3+ luminescence evidenced energy transfer.•Both ηο/η and Pda are linear in (CGd + CDy)2, suggested the dipole-dipole energy transfer nature.•The XEL study of LGBaB1.5Dy glass confirmed that the scintillation efficiency is 11% to that of BGO crystal.
Controlling the distribution of water and wastewater between industrial processes is vital to rationalize water usage and preserve the environment. In this paper, a mathematical technique is proposed ...to optimize water–wastewater networks, and a nonlinear program is introduced to minimize the consumption of freshwater and, consequently, the flowrate of wastewater discharge. A general mathematical model, able to handle industrial plants containing up to eight sources and eight sinks, is developed using LINGO optimization software to facilitate dealing with complex case studies. The introduced model can handle single-contaminant networks as well as multiple-contaminant ones. The optimal water network is synthesized through two steps; the first step involves the introduction of the case study data into the developed mathematical model. The second step considers using the optimal solution produced after running the developed LINGO model as feed data for a pre-designed Excel sheet able to deal with these results and simultaneously draw the optimal water–wastewater network. The proposed mathematical model is applied to two case studies. The first case study includes actual data from four fertilizer plants located in Egypt; the water resources and requirements are simultaneously integrated to obtain a sensible cutting in both freshwater consumption (lowered by 52.2%) and wastewater discharge (zero wastewater discharge). The second case study regards a Brazilian petrochemical plant; the obtained results show noticeable reductions in freshwater consumption by 12.3%, while the reduction percentage of wastewater discharge is 4.5%.
Simulation is an indispensable tool for the assessment of highway-related capital investments and operational changes. Model calibration, a challenging task in any simulation study, is a crucial ...step. The model’s robustness, accuracy, and quality are directly dependent on it. Many parameters exist, and field observations are often lacking to aid in their correct specification. Recently, videos from drones have created a uniquely powerful way to aid this process. Observations of the inputs (demand), outputs (vehicles processed), processing rates (e.g., saturation flow rates), and performance results (times in system, queue dynamics, and delays) are all available simultaneously. For signalized intersections, only the signal timing events are missing, and those data can be obtained from signal timing logs. This paper illustrates how modeling teams can use drone data to calibrate model parameters pertaining to intersection operation. It shows how saturation flow rates can be adjusted for signalized intersections so that queue dynamics and delays can be matched. For roundabouts, it illustrates how critical gaps and move-up times can be adjusted to match field observations of performance. Three real-world settings with associated drone data are used as case study examples.
Background
Livin/BIRC7
is a member of the inhibitors of apoptosis proteins family which are implicated in development of cancer through the inhibition of apoptosis process. This case-control study ...was intended to investigate
livin/BIRC7
gene expression in endometrial hyperplasia and carcinoma and its correlation to some oxidative stress markers in addition to its possible diagnostic performance.
Methods
This study included 90 participants 30 endometrial hyperplasia patients, 30 endometrial carcinoma patients, and 30 healthy controls.
Livin/BIRC7
gene expression was analyzed using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Serum catalase activity was assessed by enzyme-linked immunosorbent assay (ELISA) and malondialdehyde level was measured by the colorimetric method.
Results
Livin/BIRC7
gene expression was significantly (
p
< 0.001) higher in endometrial carcinoma from patients with endometrial hyperplasia when compared to controls. A positive correlation was found between
livin/BIRC7
expression and serum catalase activity and malondialdehyde level in endometrial hyperplasia and carcinoma. The detection of
livin/BIRC7
in endometrial carcinoma has excellent sensitivity and specificity.
Conclusions
Livin/BIRC7
was overexpressed in endometrial carcinoma with excellent power to differentiate endometrial carcinoma from endometrial hyperplasia or healthy subjects, suggesting that it might be a useful molecular marker for endometrial carcinoma diagnosis.
Convex functions play an important role in many areas of mathematics. They are especially important in the study of optimization problems where they are distinguished by a number of convenient ...properties. In this paper, firstly we introduce the notion of h-exponential convex functions. This notion can be considered as generalizations of many existing definitions of convex functions. Then, we establish some well-known inequalities for the proposed notion via incomplete gamma functions. Precisely speaking, we established trapezoidal, midpoint, and He’s inequalities for h-exponential and harmonically exponential convex functions via incomplete gamma functions. Moreover, we gave several remarks to prove that our results are more generalized than the existing results in the literature.
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